diff --git a/.git-blame-ignore-revs b/.git-blame-ignore-revs
index 307e22b0df1f..b40066d05d35 100644
--- a/.git-blame-ignore-revs
+++ b/.git-blame-ignore-revs
@@ -4,3 +4,5 @@ a06baa56b95674fc626b3c3fd680d6a65357fe60
 95e00bfed801e264e9c4ac817004153ca0f19eb6
 # reformat with new rustfmt
 971c549ca334b7b7406e61e958efcca9c4152822
+# refactor infcx building
+283abbf0e7d20176f76006825b5c52e9a4234e4c
diff --git a/.mailmap b/.mailmap
index 564a68955d30..f887d29096e0 100644
--- a/.mailmap
+++ b/.mailmap
@@ -217,7 +217,7 @@ Hsiang-Cheng Yang <rick68@users.noreply.github.com>
 Ian Jackson <ijackson@chiark.greenend.org.uk> <ian.jackson@citrix.com>
 Ian Jackson <ijackson@chiark.greenend.org.uk> <ijackson+github@slimy.greenend.org.uk>
 Ian Jackson <ijackson@chiark.greenend.org.uk> <iwj@xenproject.org>
-Ibraheem Ahmed <ibrah1440@gmail.com>
+Ibraheem Ahmed <ibraheem@ibraheem.ca> <ibrah1440@gmail.com>
 Ilyong Cho <ilyoan@gmail.com>
 inquisitivecrystal <22333129+inquisitivecrystal@users.noreply.github.com>
 Irina Popa <irinagpopa@gmail.com>
diff --git a/.reuse/dep5 b/.reuse/dep5
index e040f73b9e1f..5135f92a9d82 100644
--- a/.reuse/dep5
+++ b/.reuse/dep5
@@ -6,11 +6,6 @@ Files: *
 Copyright: The Rust Project Developers (see https://thanks.rust-lang.org)
 License: MIT or Apache-2.0
 
-Files: library/std/src/sync/mpsc/mpsc_queue.rs
-       library/std/src/sync/mpsc/spsc_queue.rs
-Copyright: 2010-2011 Dmitry Vyukov
-License: BSD-2-Clause
-
 Files: src/librustdoc/html/static/fonts/FiraSans*
 Copyright: 2014, Mozilla Foundation, 2014, Telefonica S.A.
 License: OFL-1.1
diff --git a/COPYRIGHT b/COPYRIGHT
index 11335879bd4a..05993830a0fb 100644
--- a/COPYRIGHT
+++ b/COPYRIGHT
@@ -339,3 +339,53 @@ their own copyright notices and license terms:
     NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
     USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
     OF SUCH DAMAGE.
+
+* Portions of internationalization code use code or data from Unicode, which
+  carry the following license:
+
+      UNICODE, INC. LICENSE AGREEMENT - DATA FILES AND SOFTWARE
+
+    See Terms of Use <https://www.unicode.org/copyright.html>
+    for definitions of Unicode Inc.’s Data Files and Software.
+
+    NOTICE TO USER: Carefully read the following legal agreement.
+    BY DOWNLOADING, INSTALLING, COPYING OR OTHERWISE USING UNICODE INC.'S
+    DATA FILES ("DATA FILES"), AND/OR SOFTWARE ("SOFTWARE"),
+    YOU UNEQUIVOCALLY ACCEPT, AND AGREE TO BE BOUND BY, ALL OF THE
+    TERMS AND CONDITIONS OF THIS AGREEMENT.
+    IF YOU DO NOT AGREE, DO NOT DOWNLOAD, INSTALL, COPY, DISTRIBUTE OR USE
+    THE DATA FILES OR SOFTWARE.
+
+    COPYRIGHT AND PERMISSION NOTICE
+
+    Copyright © 1991-2022 Unicode, Inc. All rights reserved.
+    Distributed under the Terms of Use in https://www.unicode.org/copyright.html.
+
+    Permission is hereby granted, free of charge, to any person obtaining
+    a copy of the Unicode data files and any associated documentation
+    (the "Data Files") or Unicode software and any associated documentation
+    (the "Software") to deal in the Data Files or Software
+    without restriction, including without limitation the rights to use,
+    copy, modify, merge, publish, distribute, and/or sell copies of
+    the Data Files or Software, and to permit persons to whom the Data Files
+    or Software are furnished to do so, provided that either
+    (a) this copyright and permission notice appear with all copies
+    of the Data Files or Software, or
+    (b) this copyright and permission notice appear in associated
+    Documentation.
+
+    THE DATA FILES AND SOFTWARE ARE PROVIDED "AS IS", WITHOUT WARRANTY OF
+    ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
+    WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+    NONINFRINGEMENT OF THIRD PARTY RIGHTS.
+    IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS INCLUDED IN THIS
+    NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL
+    DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+    DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+    TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+    PERFORMANCE OF THE DATA FILES OR SOFTWARE.
+
+    Except as contained in this notice, the name of a copyright holder
+    shall not be used in advertising or otherwise to promote the sale,
+    use or other dealings in these Data Files or Software without prior
+    written authorization of the copyright holder.
diff --git a/Cargo.lock b/Cargo.lock
index 0e23c1183493..9f64aa44314d 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2,34 +2,15 @@
 # It is not intended for manual editing.
 version = 3
 
-[[package]]
-name = "addr2line"
-version = "0.16.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3e61f2b7f93d2c7d2b08263acaa4a363b3e276806c68af6134c44f523bf1aacd"
-dependencies = [
- "compiler_builtins",
- "gimli 0.25.0",
- "rustc-std-workspace-alloc",
- "rustc-std-workspace-core",
-]
-
 [[package]]
 name = "addr2line"
 version = "0.17.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b9ecd88a8c8378ca913a680cd98f0f13ac67383d35993f86c90a70e3f137816b"
-dependencies = [
- "gimli 0.26.1",
-]
-
-[[package]]
-name = "adler"
-version = "0.2.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ee2a4ec343196209d6594e19543ae87a39f96d5534d7174822a3ad825dd6ed7e"
 dependencies = [
  "compiler_builtins",
+ "gimli",
+ "rustc-std-workspace-alloc",
  "rustc-std-workspace-core",
 ]
 
@@ -38,6 +19,10 @@ name = "adler"
 version = "1.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f26201604c87b1e01bd3d98f8d5d9a8fcbb815e8cedb41ffccbeb4bf593a35fe"
+dependencies = [
+ "compiler_builtins",
+ "rustc-std-workspace-core",
+]
 
 [[package]]
 name = "ahash"
@@ -185,12 +170,12 @@ version = "0.3.66"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "cab84319d616cfb654d03394f38ab7e6f0919e181b1b57e1fd15e7fb4077d9a7"
 dependencies = [
- "addr2line 0.17.0",
+ "addr2line",
  "cc",
  "cfg-if 1.0.0",
  "libc",
- "miniz_oxide 0.5.3",
- "object 0.29.0",
+ "miniz_oxide",
+ "object",
  "rustc-demangle",
 ]
 
@@ -288,7 +273,7 @@ dependencies = [
 
 [[package]]
 name = "cargo"
-version = "0.67.0"
+version = "0.68.0"
 dependencies = [
  "anyhow",
  "atty",
@@ -427,7 +412,6 @@ dependencies = [
  "glob",
  "itertools",
  "lazy_static",
- "remove_dir_all",
  "serde_json",
  "snapbox",
  "tar",
@@ -449,7 +433,7 @@ dependencies = [
  "jobserver",
  "libc",
  "log",
- "miow",
+ "miow 0.4.0",
  "same-file",
  "shell-escape",
  "tempfile",
@@ -489,9 +473,9 @@ version = "0.1.0"
 
 [[package]]
 name = "cc"
-version = "1.0.73"
+version = "1.0.76"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2fff2a6927b3bb87f9595d67196a70493f627687a71d87a0d692242c33f58c11"
+checksum = "76a284da2e6fe2092f2353e51713435363112dfd60030e22add80be333fb928f"
 dependencies = [
  "jobserver",
 ]
@@ -518,9 +502,9 @@ dependencies = [
 
 [[package]]
 name = "chalk-derive"
-version = "0.80.0"
+version = "0.87.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d0001adf0cf12361e08b65e1898ea138f8f77d8f5177cbf29b6b3b3532252bd6"
+checksum = "d552b2fa341f5fc35c6b917b1d289d3c3a34d0b74e579390ea6192d6152a8cdb"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -530,9 +514,9 @@ dependencies = [
 
 [[package]]
 name = "chalk-engine"
-version = "0.80.0"
+version = "0.87.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c44ee96f2d67cb5193d1503f185db1abad9933a1c6e6b4169c176f90baecd393"
+checksum = "7e54ac43048cb31c470d7b3e3acd409090ef4a5abddfe02455187aebc3d6879f"
 dependencies = [
  "chalk-derive",
  "chalk-ir",
@@ -543,9 +527,9 @@ dependencies = [
 
 [[package]]
 name = "chalk-ir"
-version = "0.80.0"
+version = "0.87.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "92d8a95548f23618fda86426e4304e563ec2bb7ba0216139f0748d63c107b5f1"
+checksum = "43aa55deff4e7fbdb09fa014543372f2c95a06835ac487b9ce57b5099b950838"
 dependencies = [
  "bitflags",
  "chalk-derive",
@@ -554,9 +538,9 @@ dependencies = [
 
 [[package]]
 name = "chalk-solve"
-version = "0.80.0"
+version = "0.87.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f37f492dacfafe2e21319b80827da2779932909bb392f0cc86b2bd5c07c1b4e1"
+checksum = "61213deefc36ba265ad01c4d997e18bcddf7922862a4594a47ca4575afb3dab4"
 dependencies = [
  "chalk-derive",
  "chalk-ir",
@@ -815,7 +799,8 @@ dependencies = [
  "lazy_static",
  "lazycell",
  "libc",
- "miow",
+ "miow 0.3.7",
+ "miropt-test-tools",
  "regex",
  "rustfix",
  "serde",
@@ -839,7 +824,7 @@ dependencies = [
  "lazy_static",
  "libc",
  "log",
- "miow",
+ "miow 0.3.7",
  "regex",
  "rustfix",
  "serde",
@@ -852,9 +837,9 @@ dependencies = [
 
 [[package]]
 name = "concolor"
-version = "0.0.8"
+version = "0.0.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "015267563b1df20adccdd00cb05257b1dfbea70a04928e9cf88ffb850c1a40af"
+checksum = "b90f9dcd9490a97db91a85ccd79e38a87e14323f0bb824659ee3274e9143ba37"
 dependencies = [
  "atty",
  "bitflags",
@@ -863,9 +848,9 @@ dependencies = [
 
 [[package]]
 name = "concolor-query"
-version = "0.0.5"
+version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d6417fe6fc03a8b533fd2177742eeb39a90c7233eedec7bac96d4d6b69a09449"
+checksum = "82a90734b3d5dcf656e7624cca6bce9c3a90ee11f900e80141a7427ccfb3d317"
 
 [[package]]
 name = "content_inspector"
@@ -1035,9 +1020,9 @@ dependencies = [
 
 [[package]]
 name = "curl"
-version = "0.4.43"
+version = "0.4.44"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "37d855aeef205b43f65a5001e0997d81f8efca7badad4fad7d897aa7f0d0651f"
+checksum = "509bd11746c7ac09ebd19f0b17782eae80aadee26237658a6b4808afb5c11a22"
 dependencies = [
  "curl-sys",
  "libc",
@@ -1050,9 +1035,9 @@ dependencies = [
 
 [[package]]
 name = "curl-sys"
-version = "0.4.55+curl-7.83.1"
+version = "0.4.59+curl-7.86.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "23734ec77368ec583c2e61dd3f0b0e5c98b93abe6d2a004ca06b91dd7e3e2762"
+checksum = "6cfce34829f448b08f55b7db6d0009e23e2e86a34e8c2b366269bf5799b4a407"
 dependencies = [
  "cc",
  "libc",
@@ -1153,6 +1138,17 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "displaydoc"
+version = "0.2.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3bf95dc3f046b9da4f2d51833c0d3547d8564ef6910f5c1ed130306a75b92886"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "dlmalloc"
 version = "0.2.3"
@@ -1284,15 +1280,15 @@ checksum = "37ab347416e802de484e4d03c7316c48f1ecb56574dfd4a46a80f173ce1de04d"
 
 [[package]]
 name = "flate2"
-version = "1.0.16"
+version = "1.0.23"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "68c90b0fc46cf89d227cc78b40e494ff81287a92dd07631e5af0d06fe3cf885e"
+checksum = "b39522e96686d38f4bc984b9198e3a0613264abaebaff2c5c918bfa6b6da09af"
 dependencies = [
- "cfg-if 0.1.10",
+ "cfg-if 1.0.0",
  "crc32fast",
  "libc",
  "libz-sys",
- "miniz_oxide 0.4.0",
+ "miniz_oxide",
 ]
 
 [[package]]
@@ -1514,11 +1510,11 @@ dependencies = [
 
 [[package]]
 name = "getrandom"
-version = "0.1.14"
+version = "0.1.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7abc8dd8451921606d809ba32e95b6111925cd2906060d2dcc29c070220503eb"
+checksum = "8fc3cb4d91f53b50155bdcfd23f6a4c39ae1969c2ae85982b135750cccaf5fce"
 dependencies = [
- "cfg-if 0.1.10",
+ "cfg-if 1.0.0",
  "libc",
  "wasi 0.9.0+wasi-snapshot-preview1",
 ]
@@ -1534,25 +1530,17 @@ dependencies = [
  "wasi 0.9.0+wasi-snapshot-preview1",
 ]
 
-[[package]]
-name = "gimli"
-version = "0.25.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f0a01e0497841a3b2db4f8afa483cce65f7e96a3498bd6c541734792aeac8fe7"
-dependencies = [
- "compiler_builtins",
- "rustc-std-workspace-alloc",
- "rustc-std-workspace-core",
-]
-
 [[package]]
 name = "gimli"
 version = "0.26.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "78cc372d058dcf6d5ecd98510e7fbc9e5aec4d21de70f65fea8fecebcd881bd4"
 dependencies = [
+ "compiler_builtins",
  "fallible-iterator",
  "indexmap",
+ "rustc-std-workspace-alloc",
+ "rustc-std-workspace-core",
  "stable_deref_trait",
 ]
 
@@ -1833,11 +1821,10 @@ dependencies = [
 
 [[package]]
 name = "intl_pluralrules"
-version = "7.0.1"
+version = "7.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b18f988384267d7066cc2be425e6faf352900652c046b6971d2e228d3b1c5ecf"
+checksum = "078ea7b7c29a2b4df841a7f6ac8775ff6074020c6776d48491ce2268e068f972"
 dependencies = [
- "tinystr",
  "unic-langid",
 ]
 
@@ -2216,25 +2203,16 @@ version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "68354c5c6bd36d73ff3feceb05efa59b6acb7626617f4962be322a825e61f79a"
 
-[[package]]
-name = "miniz_oxide"
-version = "0.4.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "be0f75932c1f6cfae3c04000e40114adf955636e19040f9c0a2c380702aa1c7f"
-dependencies = [
- "adler 0.2.3",
- "compiler_builtins",
- "rustc-std-workspace-alloc",
- "rustc-std-workspace-core",
-]
-
 [[package]]
 name = "miniz_oxide"
 version = "0.5.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6f5c75688da582b8ffc1f1799e9db273f32133c49e048f614d22ec3256773ccc"
 dependencies = [
- "adler 1.0.2",
+ "adler",
+ "compiler_builtins",
+ "rustc-std-workspace-alloc",
+ "rustc-std-workspace-core",
 ]
 
 [[package]]
@@ -2246,6 +2224,15 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "miow"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a7377f7792b3afb6a3cba68daa54ca23c032137010460d667fda53a8d66be00e"
+dependencies = [
+ "windows-sys 0.28.0",
+]
+
 [[package]]
 name = "miri"
 version = "0.1.0"
@@ -2262,11 +2249,19 @@ dependencies = [
  "rand 0.8.5",
  "regex",
  "rustc-workspace-hack",
+ "rustc_version",
  "shell-escape",
  "smallvec",
  "ui_test",
 ]
 
+[[package]]
+name = "miropt-test-tools"
+version = "0.1.0"
+dependencies = [
+ "regex",
+]
+
 [[package]]
 name = "new_debug_unreachable"
 version = "1.0.4"
@@ -2319,29 +2314,20 @@ dependencies = [
  "libc",
 ]
 
-[[package]]
-name = "object"
-version = "0.26.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "39f37e50073ccad23b6d09bcb5b263f4e76d3bb6038e4a3c08e52162ffa8abc2"
-dependencies = [
- "compiler_builtins",
- "memchr",
- "rustc-std-workspace-alloc",
- "rustc-std-workspace-core",
-]
-
 [[package]]
 name = "object"
 version = "0.29.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "21158b2c33aa6d4561f1c0a6ea283ca92bc54802a93b263e910746d679a7eb53"
 dependencies = [
+ "compiler_builtins",
  "crc32fast",
  "flate2",
  "hashbrown",
  "indexmap",
  "memchr",
+ "rustc-std-workspace-alloc",
+ "rustc-std-workspace-core",
 ]
 
 [[package]]
@@ -2459,7 +2445,7 @@ name = "panic_abort"
 version = "0.0.0"
 dependencies = [
  "alloc",
- "cfg-if 0.1.10",
+ "cfg-if 1.0.0",
  "compiler_builtins",
  "core",
  "libc",
@@ -2470,7 +2456,7 @@ name = "panic_unwind"
 version = "0.0.0"
 dependencies = [
  "alloc",
- "cfg-if 0.1.10",
+ "cfg-if 1.0.0",
  "compiler_builtins",
  "core",
  "libc",
@@ -2495,7 +2481,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3742b2c103b9f06bc9fff0a37ff4912935851bee6d36f3c02bcc755bcfec228f"
 dependencies = [
  "lock_api",
- "parking_lot_core 0.9.3",
+ "parking_lot_core 0.9.4",
 ]
 
 [[package]]
@@ -2514,15 +2500,15 @@ dependencies = [
 
 [[package]]
 name = "parking_lot_core"
-version = "0.9.3"
+version = "0.9.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "09a279cbf25cb0757810394fbc1e359949b59e348145c643a939a525692e6929"
+checksum = "4dc9e0dc2adc1c69d09143aff38d3d30c5c3f0df0dad82e6d25547af174ebec0"
 dependencies = [
  "cfg-if 1.0.0",
  "libc",
  "redox_syscall",
  "smallvec",
- "windows-sys",
+ "windows-sys 0.42.0",
 ]
 
 [[package]]
@@ -2747,9 +2733,9 @@ dependencies = [
 
 [[package]]
 name = "psm"
-version = "0.1.16"
+version = "0.1.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cd136ff4382c4753fc061cb9e4712ab2af263376b95bbd5bd8cd50c020b78e69"
+checksum = "5787f7cda34e3033a72192c018bc5883100330f362ef279a8cbccfce8bb4e874"
 dependencies = [
  "cc",
 ]
@@ -2798,7 +2784,7 @@ version = "0.7.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6a6b1679d49b24bbfe0c803429aa1874472f50d9b363131f0e89fc356b544d03"
 dependencies = [
- "getrandom 0.1.14",
+ "getrandom 0.1.16",
  "libc",
  "rand_chacha 0.2.2",
  "rand_core 0.5.1",
@@ -2842,7 +2828,7 @@ version = "0.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "90bde5296fc891b0cef12a6d03ddccc162ce7b2aff54160af9338f8d40df6d19"
 dependencies = [
- "getrandom 0.1.14",
+ "getrandom 0.1.16",
 ]
 
 [[package]]
@@ -3278,7 +3264,7 @@ dependencies = [
  "cstr",
  "libc",
  "measureme",
- "object 0.29.0",
+ "object",
  "rustc-demangle",
  "rustc_ast",
  "rustc_attr",
@@ -3312,7 +3298,7 @@ dependencies = [
  "itertools",
  "jobserver",
  "libc",
- "object 0.29.0",
+ "object",
  "pathdiff",
  "regex",
  "rustc_arena",
@@ -3645,7 +3631,6 @@ dependencies = [
 name = "rustc_interface"
 version = "0.0.0"
 dependencies = [
- "libc",
  "libloading",
  "rustc-rayon",
  "rustc-rayon-core",
@@ -3688,7 +3673,6 @@ dependencies = [
  "rustc_ty_utils",
  "smallvec",
  "tracing",
- "winapi",
 ]
 
 [[package]]
@@ -4108,6 +4092,7 @@ name = "rustc_session"
 version = "0.0.0"
 dependencies = [
  "getopts",
+ "libc",
  "rustc_ast",
  "rustc_data_structures",
  "rustc_errors",
@@ -4119,7 +4104,9 @@ dependencies = [
  "rustc_serialize",
  "rustc_span",
  "rustc_target",
+ "smallvec",
  "tracing",
+ "winapi",
 ]
 
 [[package]]
@@ -4609,9 +4596,9 @@ checksum = "da73c8f77aebc0e40c300b93f0a5f1bece7a248a36eee287d4e095f35c7b7d6e"
 
 [[package]]
 name = "snapbox"
-version = "0.3.3"
+version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "44d199ccf8f606592df2d145db26f2aa45344e23c64b074cc5a4047f1d99b0f7"
+checksum = "827c00e91b15e2674d8a5270bae91f898693cbf9561cbb58d8eaa31974597293"
 dependencies = [
  "concolor",
  "content_inspector",
@@ -4649,9 +4636,9 @@ checksum = "a8f112729512f8e442d81f95a8a7ddf2b7c6b8a1a6f509a95864142b30cab2d3"
 
 [[package]]
 name = "stacker"
-version = "0.1.14"
+version = "0.1.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "90939d5171a4420b3ff5fbc8954d641e7377335454c259dcb80786f3f21dc9b4"
+checksum = "c886bd4480155fd3ef527d45e9ac8dd7118a898a46530b7b94c3e21866259fce"
 dependencies = [
  "cc",
  "cfg-if 1.0.0",
@@ -4670,7 +4657,7 @@ checksum = "a2eb9349b6444b326872e140eb1cf5e7c522154d69e7a0ffb0fb81c06b37543f"
 name = "std"
 version = "0.0.0"
 dependencies = [
- "addr2line 0.16.0",
+ "addr2line",
  "alloc",
  "cfg-if 1.0.0",
  "compiler_builtins",
@@ -4680,8 +4667,8 @@ dependencies = [
  "hashbrown",
  "hermit-abi 0.2.6",
  "libc",
- "miniz_oxide 0.4.0",
- "object 0.26.2",
+ "miniz_oxide",
+ "object",
  "panic_abort",
  "panic_unwind",
  "profiler_builtins",
@@ -4868,9 +4855,9 @@ checksum = "b1141d4d61095b28419e22cb0bbf02755f5e54e0526f97f1e3d1d160e60885fb"
 
 [[package]]
 name = "thin-vec"
-version = "0.2.8"
+version = "0.2.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "104c2cb3180b6fb6d5b2278768e9b88b578d32ba751ea6e8d026688a40d7ed87"
+checksum = "ceb05e71730d396f960f8f3901cdb41be2d339b303e9d7d3a07c5ff0536e671b"
 
 [[package]]
 name = "thiserror"
@@ -4898,9 +4885,9 @@ version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e6cb0c7868d7f90407531108ab03263d9452a8811b7cdd87675343a40d4aa254"
 dependencies = [
- "gimli 0.26.1",
+ "gimli",
  "hashbrown",
- "object 0.29.0",
+ "object",
  "tracing",
 ]
 
@@ -4918,7 +4905,9 @@ name = "tidy"
 version = "0.1.0"
 dependencies = [
  "cargo_metadata 0.14.0",
+ "ignore",
  "lazy_static",
+ "miropt-test-tools",
  "regex",
  "walkdir",
 ]
@@ -4939,9 +4928,12 @@ dependencies = [
 
 [[package]]
 name = "tinystr"
-version = "0.3.4"
+version = "0.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "29738eedb4388d9ea620eeab9384884fc3f06f586a2eddb56bedc5885126c7c1"
+checksum = "f8aeafdfd935e4a7fe16a91ab711fa52d54df84f9c8f7ca5837a9d1d902ef4c2"
+dependencies = [
+ "displaydoc",
+]
 
 [[package]]
 name = "tinyvec"
@@ -5177,9 +5169,9 @@ dependencies = [
 
 [[package]]
 name = "unic-langid"
-version = "0.9.0"
+version = "0.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "73328fcd730a030bdb19ddf23e192187a6b01cd98be6d3140622a89129459ce5"
+checksum = "398f9ad7239db44fd0f80fe068d12ff22d78354080332a5077dc6f52f14dcf2f"
 dependencies = [
  "unic-langid-impl",
  "unic-langid-macros",
@@ -5187,18 +5179,18 @@ dependencies = [
 
 [[package]]
 name = "unic-langid-impl"
-version = "0.9.0"
+version = "0.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1a4a8eeaf0494862c1404c95ec2f4c33a2acff5076f64314b465e3ddae1b934d"
+checksum = "e35bfd2f2b8796545b55d7d3fd3e89a0613f68a0d1c8bc28cb7ff96b411a35ff"
 dependencies = [
  "tinystr",
 ]
 
 [[package]]
 name = "unic-langid-macros"
-version = "0.9.0"
+version = "0.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "18f980d6d87e8805f2836d64b4138cc95aa7986fa63b1f51f67d5fbff64dd6e5"
+checksum = "055e618bf694161ffff0466d95cef3e1a5edc59f6ba1888e97801f2b4ebdc4fe"
 dependencies = [
  "proc-macro-hack",
  "tinystr",
@@ -5208,9 +5200,9 @@ dependencies = [
 
 [[package]]
 name = "unic-langid-macros-impl"
-version = "0.9.0"
+version = "0.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "29396ffd97e27574c3e01368b1a64267d3064969e4848e2e130ff668be9daa9f"
+checksum = "1f5cdec05b907f4e2f6843f4354f4ce6a5bebe1a56df320a49134944477ce4d8"
 dependencies = [
  "proc-macro-hack",
  "quote",
@@ -5334,7 +5326,7 @@ name = "unwind"
 version = "0.0.0"
 dependencies = [
  "cc",
- "cfg-if 0.1.10",
+ "cfg-if 1.0.0",
  "compiler_builtins",
  "core",
  "libc",
@@ -5453,46 +5445,103 @@ checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
 
 [[package]]
 name = "windows-sys"
-version = "0.36.1"
+version = "0.28.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ea04155a16a59f9eab786fe12a4a450e75cdb175f9e0d80da1e17db09f55b8d2"
+checksum = "82ca39602d5cbfa692c4b67e3bcbb2751477355141c1ed434c94da4186836ff6"
 dependencies = [
- "windows_aarch64_msvc",
- "windows_i686_gnu",
- "windows_i686_msvc",
- "windows_x86_64_gnu",
- "windows_x86_64_msvc",
+ "windows_aarch64_msvc 0.28.0",
+ "windows_i686_gnu 0.28.0",
+ "windows_i686_msvc 0.28.0",
+ "windows_x86_64_gnu 0.28.0",
+ "windows_x86_64_msvc 0.28.0",
 ]
 
 [[package]]
-name = "windows_aarch64_msvc"
-version = "0.36.1"
+name = "windows-sys"
+version = "0.42.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9bb8c3fd39ade2d67e9874ac4f3db21f0d710bee00fe7cab16949ec184eeaa47"
+checksum = "5a3e1820f08b8513f676f7ab6c1f99ff312fb97b553d30ff4dd86f9f15728aa7"
+dependencies = [
+ "windows_aarch64_gnullvm",
+ "windows_aarch64_msvc 0.42.0",
+ "windows_i686_gnu 0.42.0",
+ "windows_i686_msvc 0.42.0",
+ "windows_x86_64_gnu 0.42.0",
+ "windows_x86_64_gnullvm",
+ "windows_x86_64_msvc 0.42.0",
+]
+
+[[package]]
+name = "windows_aarch64_gnullvm"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "41d2aa71f6f0cbe00ae5167d90ef3cfe66527d6f613ca78ac8024c3ccab9a19e"
+
+[[package]]
+name = "windows_aarch64_msvc"
+version = "0.28.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "52695a41e536859d5308cc613b4a022261a274390b25bd29dfff4bf08505f3c2"
+
+[[package]]
+name = "windows_aarch64_msvc"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dd0f252f5a35cac83d6311b2e795981f5ee6e67eb1f9a7f64eb4500fbc4dcdb4"
 
 [[package]]
 name = "windows_i686_gnu"
-version = "0.36.1"
+version = "0.28.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "180e6ccf01daf4c426b846dfc66db1fc518f074baa793aa7d9b9aaeffad6a3b6"
+checksum = "f54725ac23affef038fecb177de6c9bf065787c2f432f79e3c373da92f3e1d8a"
+
+[[package]]
+name = "windows_i686_gnu"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fbeae19f6716841636c28d695375df17562ca208b2b7d0dc47635a50ae6c5de7"
 
 [[package]]
 name = "windows_i686_msvc"
-version = "0.36.1"
+version = "0.28.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e2e7917148b2812d1eeafaeb22a97e4813dfa60a3f8f78ebe204bcc88f12f024"
+checksum = "51d5158a43cc43623c0729d1ad6647e62fa384a3d135fd15108d37c683461f64"
+
+[[package]]
+name = "windows_i686_msvc"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "84c12f65daa39dd2babe6e442988fc329d6243fdce47d7d2d155b8d874862246"
 
 [[package]]
 name = "windows_x86_64_gnu"
-version = "0.36.1"
+version = "0.28.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4dcd171b8776c41b97521e5da127a2d86ad280114807d0b2ab1e462bc764d9e1"
+checksum = "bc31f409f565611535130cfe7ee8e6655d3fa99c1c61013981e491921b5ce954"
+
+[[package]]
+name = "windows_x86_64_gnu"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bf7b1b21b5362cbc318f686150e5bcea75ecedc74dd157d874d754a2ca44b0ed"
+
+[[package]]
+name = "windows_x86_64_gnullvm"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "09d525d2ba30eeb3297665bd434a54297e4170c7f1a44cad4ef58095b4cd2028"
 
 [[package]]
 name = "windows_x86_64_msvc"
-version = "0.36.1"
+version = "0.28.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c811ca4a8c853ef420abd8592ba53ddbbac90410fab6903b3e79972a631f7680"
+checksum = "3f2b8c7cbd3bfdddd9ab98769f9746a7fad1bca236554cd032b78d768bc0e89f"
+
+[[package]]
+name = "windows_x86_64_msvc"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f40009d85759725a34da6d89a94e63d7bdc50a862acf0dbc7c8e488f1edcb6f5"
 
 [[package]]
 name = "xattr"
diff --git a/Cargo.toml b/Cargo.toml
index e49fe5e2f635..13a98eedde86 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -11,6 +11,7 @@ members = [
   "src/tools/error_index_generator",
   "src/tools/linkchecker",
   "src/tools/lint-docs",
+  "src/tools/miropt-test-tools",
   "src/tools/rustbook",
   "src/tools/unstable-book-gen",
   "src/tools/tidy",
diff --git a/LICENSES/BSD-2-Clause.txt b/LICENSES/BSD-2-Clause.txt
deleted file mode 100644
index 5f662b354cd4..000000000000
--- a/LICENSES/BSD-2-Clause.txt
+++ /dev/null
@@ -1,9 +0,0 @@
-Copyright (c) <year> <owner> 
-
-Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
-
-1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
-
-2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
-
-THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/RELEASES.md b/RELEASES.md
index 694bd09658f7..5c1990bb6c97 100644
--- a/RELEASES.md
+++ b/RELEASES.md
@@ -1,3 +1,109 @@
+Version 1.65.0 (2022-11-03)
+==========================
+
+Language
+--------
+- [Error on `as` casts of enums with `#[non_exhaustive]` variants](https://github.com/rust-lang/rust/pull/92744/)
+- [Stabilize `let else`](https://github.com/rust-lang/rust/pull/93628/)
+- [Stabilize generic associated types (GATs)](https://github.com/rust-lang/rust/pull/96709/)
+- [Add lints `let_underscore_drop` and `let_underscore_lock` from Clippy](https://github.com/rust-lang/rust/pull/97739/)
+- [Stabilize `break`ing from arbitrary labeled blocks ("label-break-value")](https://github.com/rust-lang/rust/pull/99332/)
+- [Uninitialized integers, floats, and raw pointers are now considered immediate UB](https://github.com/rust-lang/rust/pull/98919/).
+  Usage of `MaybeUninit` is the correct way to work with uninitialized memory.
+- [Stabilize raw-dylib for Windows x86_64, aarch64, and thumbv7a](https://github.com/rust-lang/rust/pull/99916/)
+- [Do not allow `Drop` impl on foreign ADTs](https://github.com/rust-lang/rust/pull/99576/)
+
+Compiler
+--------
+- [Stabilize -Csplit-debuginfo on Linux](https://github.com/rust-lang/rust/pull/98051/)
+- [Use niche-filling optimization even when multiple variants have data](https://github.com/rust-lang/rust/pull/94075/)
+- [Associated type projections are now verified to be well-formed prior to resolving the underlying type](https://github.com/rust-lang/rust/pull/99217/#issuecomment-1209365630)
+- [Stringify non-shorthand visibility correctly](https://github.com/rust-lang/rust/pull/100350/)
+- [Normalize struct field types when unsizing](https://github.com/rust-lang/rust/pull/101831/)
+- [Update to LLVM 15](https://github.com/rust-lang/rust/pull/99464/)
+- [Fix aarch64 call abi to correctly zeroext when needed](https://github.com/rust-lang/rust/pull/97800/)
+- [debuginfo: Generalize C++-like encoding for enums](https://github.com/rust-lang/rust/pull/98393/)
+- [Add `special_module_name` lint](https://github.com/rust-lang/rust/pull/94467/)
+- [Add support for generating unique profraw files by default when using `-C instrument-coverage`](https://github.com/rust-lang/rust/pull/100384/)
+- [Allow dynamic linking for iOS/tvOS targets](https://github.com/rust-lang/rust/pull/100636/)
+
+New targets:
+
+- [Add armv4t-none-eabi as a tier 3 target](https://github.com/rust-lang/rust/pull/100244/)
+- [Add powerpc64-unknown-openbsd and riscv64-unknown-openbsd as tier 3 targets](https://github.com/rust-lang/rust/pull/101025/)
+  - Refer to Rust's [platform support page][platform-support-doc] for more
+    information on Rust's tiered platform support.
+
+Libraries
+---------
+
+- [Don't generate `PartialEq::ne` in derive(PartialEq)](https://github.com/rust-lang/rust/pull/98655/)
+- [Windows RNG: Use `BCRYPT_RNG_ALG_HANDLE` by default](https://github.com/rust-lang/rust/pull/101325/)
+- [Forbid mixing `System` with direct system allocator calls](https://github.com/rust-lang/rust/pull/101394/)
+- [Document no support for writing to non-blocking stdio/stderr](https://github.com/rust-lang/rust/pull/101416/)
+- [`std::layout::Layout` size must not overflow `isize::MAX` when rounded up to `align`](https://github.com/rust-lang/rust/pull/95295)
+  This also changes the safety conditions on `Layout::from_size_align_unchecked`.
+
+Stabilized APIs
+---------------
+
+- [`std::backtrace::Backtrace`](https://doc.rust-lang.org/stable/std/backtrace/struct.Backtrace.html)
+- [`Bound::as_ref`](https://doc.rust-lang.org/stable/std/ops/enum.Bound.html#method.as_ref)
+- [`std::io::read_to_string`](https://doc.rust-lang.org/stable/std/io/fn.read_to_string.html)
+- [`<*const T>::cast_mut`](https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.cast_mut)
+- [`<*mut T>::cast_const`](https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.cast_const)
+
+These APIs are now stable in const contexts:
+
+- [`<*const T>::offset_from`](https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.offset_from)
+- [`<*mut T>::offset_from`](https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.offset_from)
+
+Cargo
+-----
+
+- [Apply GitHub fast path even for partial hashes](https://github.com/rust-lang/cargo/pull/10807/)
+- [Do not add home bin path to PATH if it's already there](https://github.com/rust-lang/cargo/pull/11023/)
+- [Take priority into account within the pending queue](https://github.com/rust-lang/cargo/pull/11032/).
+  This slightly optimizes job scheduling by Cargo, with typically small improvements on larger crate graph builds.
+
+Compatibility Notes
+-------------------
+
+- [`std::layout::Layout` size must not overflow `isize::MAX` when rounded up to `align`](https://github.com/rust-lang/rust/pull/95295).
+  This also changes the safety conditions on `Layout::from_size_align_unchecked`.
+- [`PollFn` now only implements `Unpin` if the closure is `Unpin`](https://github.com/rust-lang/rust/pull/102737).
+  This is a possible breaking change if users were relying on the blanket unpin implementation.
+  See discussion on the PR for details of why this change was made.
+- [Drop ExactSizeIterator impl from std::char::EscapeAscii](https://github.com/rust-lang/rust/pull/99880)
+  This is a backwards-incompatible change to the standard library's surface
+  area, but is unlikely to affect real world usage.
+- [Do not consider a single repeated lifetime eligible for elision in the return type](https://github.com/rust-lang/rust/pull/103450)
+  This behavior was unintentionally changed in 1.64.0, and this release reverts that change by making this an error again.
+- [Reenable disabled early syntax gates as future-incompatibility lints](https://github.com/rust-lang/rust/pull/99935/)
+- [Update the minimum external LLVM to 13](https://github.com/rust-lang/rust/pull/100460/)
+- [Don't duplicate file descriptors into stdio fds](https://github.com/rust-lang/rust/pull/101426/)
+- [Sunset RLS](https://github.com/rust-lang/rust/pull/100863/)
+- [Deny usage of `#![cfg_attr(..., crate_type = ...)]` to set the crate type](https://github.com/rust-lang/rust/pull/99784/)
+  This strengthens the forward compatibility lint deprecated_cfg_attr_crate_type_name to deny.
+- [`llvm-has-rust-patches` allows setting the build system to treat the LLVM as having Rust-specific patches](https://github.com/rust-lang/rust/pull/101072)
+  This option may need to be set for distributions that are building Rust with a patched LLVM via `llvm-config`, not the built-in LLVM.
+- Combining three or more languages (e.g. Objective C, C++ and Rust) into one binary may hit linker limitations when using `lld`. For more information, see [issue 102754][102754].
+
+[102754]: https://github.com/rust-lang/rust/issues/102754
+
+Internal Changes
+----------------
+
+These changes do not affect any public interfaces of Rust, but they represent
+significant improvements to the performance or internals of rustc and related
+tools.
+
+- [Add `x.sh` and `x.ps1` shell scripts](https://github.com/rust-lang/rust/pull/99992/)
+- [compiletest: use target cfg instead of hard-coded tables](https://github.com/rust-lang/rust/pull/100260/)
+- [Use object instead of LLVM for reading bitcode from rlibs](https://github.com/rust-lang/rust/pull/98100/)
+- [Enable MIR inlining for optimized compilations](https://github.com/rust-lang/rust/pull/91743)
+  This provides a 3-10% improvement in compiletimes for real world crates. See [perf results](https://perf.rust-lang.org/compare.html?start=aedf78e56b2279cc869962feac5153b6ba7001ed&end=0075bb4fad68e64b6d1be06bf2db366c30bc75e1&stat=instructions:u).
+
 Version 1.64.0 (2022-09-22)
 ===========================
 
diff --git a/compiler/rustc/src/main.rs b/compiler/rustc/src/main.rs
index 0de1a7819135..e21c9b660444 100644
--- a/compiler/rustc/src/main.rs
+++ b/compiler/rustc/src/main.rs
@@ -1,3 +1,5 @@
+#![feature(unix_sigpipe)]
+
 // A note about jemalloc: rustc uses jemalloc when built for CI and
 // distribution. The obvious way to do this is with the `#[global_allocator]`
 // mechanism. However, for complicated reasons (see
@@ -23,6 +25,7 @@
 // libraries. So we must reference jemalloc symbols one way or another, because
 // this file is the only object code in the rustc executable.
 
+#[unix_sigpipe = "sig_dfl"]
 fn main() {
     // See the comment at the top of this file for an explanation of this.
     #[cfg(feature = "jemalloc-sys")]
@@ -58,6 +61,5 @@ fn main() {
         }
     }
 
-    rustc_driver::set_sigpipe_handler();
     rustc_driver::main()
 }
diff --git a/compiler/rustc_ast/Cargo.toml b/compiler/rustc_ast/Cargo.toml
index fcbf96818250..9253b7e6891a 100644
--- a/compiler/rustc_ast/Cargo.toml
+++ b/compiler/rustc_ast/Cargo.toml
@@ -14,5 +14,5 @@ rustc_macros = { path = "../rustc_macros" }
 rustc_serialize = { path = "../rustc_serialize" }
 rustc_span = { path = "../rustc_span" }
 smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
-thin-vec = "0.2.8"
+thin-vec = "0.2.9"
 tracing = "0.1"
diff --git a/compiler/rustc_ast/src/ast.rs b/compiler/rustc_ast/src/ast.rs
index 7112c2675771..2cbab90aa61a 100644
--- a/compiler/rustc_ast/src/ast.rs
+++ b/compiler/rustc_ast/src/ast.rs
@@ -392,15 +392,7 @@ pub struct Generics {
 impl Default for Generics {
     /// Creates an instance of `Generics`.
     fn default() -> Generics {
-        Generics {
-            params: Vec::new(),
-            where_clause: WhereClause {
-                has_where_token: false,
-                predicates: Vec::new(),
-                span: DUMMY_SP,
-            },
-            span: DUMMY_SP,
-        }
+        Generics { params: Vec::new(), where_clause: Default::default(), span: DUMMY_SP }
     }
 }
 
@@ -415,6 +407,12 @@ pub struct WhereClause {
     pub span: Span,
 }
 
+impl Default for WhereClause {
+    fn default() -> WhereClause {
+        WhereClause { has_where_token: false, predicates: Vec::new(), span: DUMMY_SP }
+    }
+}
+
 /// A single predicate in a where-clause.
 #[derive(Clone, Encodable, Decodable, Debug)]
 pub enum WherePredicate {
@@ -1112,24 +1110,6 @@ pub struct Expr {
 }
 
 impl Expr {
-    /// Returns `true` if this expression would be valid somewhere that expects a value;
-    /// for example, an `if` condition.
-    pub fn returns(&self) -> bool {
-        if let ExprKind::Block(ref block, _) = self.kind {
-            match block.stmts.last().map(|last_stmt| &last_stmt.kind) {
-                // Implicit return
-                Some(StmtKind::Expr(_)) => true,
-                // Last statement is an explicit return?
-                Some(StmtKind::Semi(expr)) => matches!(expr.kind, ExprKind::Ret(_)),
-                // This is a block that doesn't end in either an implicit or explicit return.
-                _ => false,
-            }
-        } else {
-            // This is not a block, it is a value.
-            true
-        }
-    }
-
     /// Is this expr either `N`, or `{ N }`.
     ///
     /// If this is not the case, name resolution does not resolve `N` when using
@@ -1226,7 +1206,7 @@ impl Expr {
             ExprKind::Tup(_) => ExprPrecedence::Tup,
             ExprKind::Binary(op, ..) => ExprPrecedence::Binary(op.node),
             ExprKind::Unary(..) => ExprPrecedence::Unary,
-            ExprKind::Lit(_) => ExprPrecedence::Lit,
+            ExprKind::Lit(_) | ExprKind::IncludedBytes(..) => ExprPrecedence::Lit,
             ExprKind::Type(..) | ExprKind::Cast(..) => ExprPrecedence::Cast,
             ExprKind::Let(..) => ExprPrecedence::Let,
             ExprKind::If(..) => ExprPrecedence::If,
@@ -1464,6 +1444,12 @@ pub enum ExprKind {
     /// with an optional value to be returned.
     Yeet(Option<P<Expr>>),
 
+    /// Bytes included via `include_bytes!`
+    /// Added for optimization purposes to avoid the need to escape
+    /// large binary blobs - should always behave like [`ExprKind::Lit`]
+    /// with a `ByteStr` literal.
+    IncludedBytes(Lrc<[u8]>),
+
     /// Placeholder for an expression that wasn't syntactically well formed in some way.
     Err,
 }
diff --git a/compiler/rustc_ast/src/lib.rs b/compiler/rustc_ast/src/lib.rs
index eeb7e56e2b12..9c1dfeb1a614 100644
--- a/compiler/rustc_ast/src/lib.rs
+++ b/compiler/rustc_ast/src/lib.rs
@@ -29,6 +29,7 @@ extern crate rustc_macros;
 extern crate tracing;
 
 pub mod util {
+    pub mod case;
     pub mod classify;
     pub mod comments;
     pub mod literal;
diff --git a/compiler/rustc_ast/src/mut_visit.rs b/compiler/rustc_ast/src/mut_visit.rs
index 25022a02f4bb..3ab8267263d1 100644
--- a/compiler/rustc_ast/src/mut_visit.rs
+++ b/compiler/rustc_ast/src/mut_visit.rs
@@ -152,6 +152,12 @@ pub trait MutVisitor: Sized {
         noop_visit_expr(e, self);
     }
 
+    /// This method is a hack to workaround unstable of `stmt_expr_attributes`.
+    /// It can be removed once that feature is stabilized.
+    fn visit_method_receiver_expr(&mut self, ex: &mut P<Expr>) {
+        self.visit_expr(ex)
+    }
+
     fn filter_map_expr(&mut self, e: P<Expr>) -> Option<P<Expr>> {
         noop_filter_map_expr(e, self)
     }
@@ -1301,7 +1307,7 @@ pub fn noop_visit_expr<T: MutVisitor>(
             vis.visit_ident(ident);
             vis.visit_id(id);
             visit_opt(args, |args| vis.visit_generic_args(args));
-            vis.visit_expr(receiver);
+            vis.visit_method_receiver_expr(receiver);
             visit_exprs(exprs, vis);
             vis.visit_span(span);
         }
@@ -1422,7 +1428,7 @@ pub fn noop_visit_expr<T: MutVisitor>(
         }
         ExprKind::Try(expr) => vis.visit_expr(expr),
         ExprKind::TryBlock(body) => vis.visit_block(body),
-        ExprKind::Lit(_) | ExprKind::Err => {}
+        ExprKind::Lit(_) | ExprKind::IncludedBytes(..) | ExprKind::Err => {}
     }
     vis.visit_id(id);
     vis.visit_span(span);
@@ -1589,3 +1595,9 @@ impl DummyAstNode for Crate {
         }
     }
 }
+
+impl<N: DummyAstNode, T: DummyAstNode> DummyAstNode for crate::ast_traits::AstNodeWrapper<N, T> {
+    fn dummy() -> Self {
+        crate::ast_traits::AstNodeWrapper::new(N::dummy(), T::dummy())
+    }
+}
diff --git a/compiler/rustc_ast/src/token.rs b/compiler/rustc_ast/src/token.rs
index 83b10d906e29..f6aac0b55f1a 100644
--- a/compiler/rustc_ast/src/token.rs
+++ b/compiler/rustc_ast/src/token.rs
@@ -5,6 +5,7 @@ pub use TokenKind::*;
 
 use crate::ast;
 use crate::ptr::P;
+use crate::util::case::Case;
 
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_data_structures::sync::Lrc;
@@ -615,6 +616,15 @@ impl Token {
         self.is_non_raw_ident_where(|id| id.name == kw)
     }
 
+    /// Returns `true` if the token is a given keyword, `kw` or if `case` is `Insensitive` and this token is an identifier equal to `kw` ignoring the case.
+    pub fn is_keyword_case(&self, kw: Symbol, case: Case) -> bool {
+        self.is_keyword(kw)
+            || (case == Case::Insensitive
+                && self.is_non_raw_ident_where(|id| {
+                    id.name.as_str().to_lowercase() == kw.as_str().to_lowercase()
+                }))
+    }
+
     pub fn is_path_segment_keyword(&self) -> bool {
         self.is_non_raw_ident_where(Ident::is_path_segment_keyword)
     }
diff --git a/compiler/rustc_ast/src/util/case.rs b/compiler/rustc_ast/src/util/case.rs
new file mode 100644
index 000000000000..1afd7dea7408
--- /dev/null
+++ b/compiler/rustc_ast/src/util/case.rs
@@ -0,0 +1,6 @@
+/// Whatever to ignore case (`fn` vs `Fn` vs `FN`) or not. Used for recovering.
+#[derive(Copy, Clone, Debug, Eq, PartialEq)]
+pub enum Case {
+    Sensitive,
+    Insensitive,
+}
diff --git a/compiler/rustc_ast/src/util/literal.rs b/compiler/rustc_ast/src/util/literal.rs
index 536b385606c6..e267f8cd1002 100644
--- a/compiler/rustc_ast/src/util/literal.rs
+++ b/compiler/rustc_ast/src/util/literal.rs
@@ -2,12 +2,10 @@
 
 use crate::ast::{self, Lit, LitKind};
 use crate::token::{self, Token};
-
-use rustc_lexer::unescape::{unescape_byte, unescape_char};
-use rustc_lexer::unescape::{unescape_byte_literal, unescape_literal, Mode};
+use rustc_data_structures::sync::Lrc;
+use rustc_lexer::unescape::{byte_from_char, unescape_byte, unescape_char, unescape_literal, Mode};
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_span::Span;
-
 use std::ascii;
 
 pub enum LitError {
@@ -109,13 +107,11 @@ impl LitKind {
                 let s = symbol.as_str();
                 let mut buf = Vec::with_capacity(s.len());
                 let mut error = Ok(());
-                unescape_byte_literal(&s, Mode::ByteStr, &mut |_, unescaped_byte| {
-                    match unescaped_byte {
-                        Ok(c) => buf.push(c),
-                        Err(err) => {
-                            if err.is_fatal() {
-                                error = Err(LitError::LexerError);
-                            }
+                unescape_literal(&s, Mode::ByteStr, &mut |_, c| match c {
+                    Ok(c) => buf.push(byte_from_char(c)),
+                    Err(err) => {
+                        if err.is_fatal() {
+                            error = Err(LitError::LexerError);
                         }
                     }
                 });
@@ -127,13 +123,11 @@ impl LitKind {
                 let bytes = if s.contains('\r') {
                     let mut buf = Vec::with_capacity(s.len());
                     let mut error = Ok(());
-                    unescape_byte_literal(&s, Mode::RawByteStr, &mut |_, unescaped_byte| {
-                        match unescaped_byte {
-                            Ok(c) => buf.push(c),
-                            Err(err) => {
-                                if err.is_fatal() {
-                                    error = Err(LitError::LexerError);
-                                }
+                    unescape_literal(&s, Mode::RawByteStr, &mut |_, c| match c {
+                        Ok(c) => buf.push(byte_from_char(c)),
+                        Err(err) => {
+                            if err.is_fatal() {
+                                error = Err(LitError::LexerError);
                             }
                         }
                     });
@@ -238,6 +232,13 @@ impl Lit {
         Lit { token_lit: kind.to_token_lit(), kind, span }
     }
 
+    /// Recovers an AST literal from a string of bytes produced by `include_bytes!`.
+    /// This requires ASCII-escaping the string, which can result in poor performance
+    /// for very large strings of bytes.
+    pub fn from_included_bytes(bytes: &Lrc<[u8]>, span: Span) -> Lit {
+        Self::from_lit_kind(LitKind::ByteStr(bytes.clone()), span)
+    }
+
     /// Losslessly convert an AST literal into a token.
     pub fn to_token(&self) -> Token {
         let kind = match self.token_lit.kind {
diff --git a/compiler/rustc_ast/src/visit.rs b/compiler/rustc_ast/src/visit.rs
index e752cc7dc2dc..da0545ce80c3 100644
--- a/compiler/rustc_ast/src/visit.rs
+++ b/compiler/rustc_ast/src/visit.rs
@@ -140,6 +140,11 @@ pub trait Visitor<'ast>: Sized {
     fn visit_expr(&mut self, ex: &'ast Expr) {
         walk_expr(self, ex)
     }
+    /// This method is a hack to workaround unstable of `stmt_expr_attributes`.
+    /// It can be removed once that feature is stabilized.
+    fn visit_method_receiver_expr(&mut self, ex: &'ast Expr) {
+        self.visit_expr(ex)
+    }
     fn visit_expr_post(&mut self, _ex: &'ast Expr) {}
     fn visit_ty(&mut self, t: &'ast Ty) {
         walk_ty(self, t)
@@ -246,7 +251,7 @@ pub trait Visitor<'ast>: Sized {
 macro_rules! walk_list {
     ($visitor: expr, $method: ident, $list: expr $(, $($extra_args: expr),* )?) => {
         {
-            #[cfg_attr(not(bootstrap), allow(for_loops_over_fallibles))]
+            #[allow(for_loops_over_fallibles)]
             for elem in $list {
                 $visitor.$method(elem $(, $($extra_args,)* )?)
             }
@@ -896,7 +901,7 @@ pub fn walk_expr<'a, V: Visitor<'a>>(visitor: &mut V, expression: &'a Expr) {
         }
         ExprKind::Try(ref subexpression) => visitor.visit_expr(subexpression),
         ExprKind::TryBlock(ref body) => visitor.visit_block(body),
-        ExprKind::Lit(_) | ExprKind::Err => {}
+        ExprKind::Lit(_) | ExprKind::IncludedBytes(..) | ExprKind::Err => {}
     }
 
     visitor.visit_expr_post(expression)
diff --git a/compiler/rustc_ast_lowering/Cargo.toml b/compiler/rustc_ast_lowering/Cargo.toml
index ce1c8d4997d7..6a59b9e6151c 100644
--- a/compiler/rustc_ast_lowering/Cargo.toml
+++ b/compiler/rustc_ast_lowering/Cargo.toml
@@ -21,5 +21,5 @@ rustc_session = { path = "../rustc_session" }
 rustc_span = { path = "../rustc_span" }
 rustc_target = { path = "../rustc_target" }
 smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
-thin-vec = "0.2.8"
+thin-vec = "0.2.9"
 tracing = "0.1"
diff --git a/compiler/rustc_ast_lowering/src/errors.rs b/compiler/rustc_ast_lowering/src/errors.rs
index 157f46501e14..21c6a2d26f4c 100644
--- a/compiler/rustc_ast_lowering/src/errors.rs
+++ b/compiler/rustc_ast_lowering/src/errors.rs
@@ -277,8 +277,9 @@ pub struct RegisterConflict<'a> {
 pub struct SubTupleBinding<'a> {
     #[primary_span]
     #[label]
-    #[suggestion_verbose(
+    #[suggestion(
         ast_lowering_sub_tuple_binding_suggestion,
+        style = "verbose",
         code = "..",
         applicability = "maybe-incorrect"
     )]
diff --git a/compiler/rustc_ast_lowering/src/expr.rs b/compiler/rustc_ast_lowering/src/expr.rs
index ec9c39350205..a4ae493af86b 100644
--- a/compiler/rustc_ast_lowering/src/expr.rs
+++ b/compiler/rustc_ast_lowering/src/expr.rs
@@ -87,6 +87,10 @@ impl<'hir> LoweringContext<'_, 'hir> {
                 ExprKind::Lit(ref l) => {
                     hir::ExprKind::Lit(respan(self.lower_span(l.span), l.kind.clone()))
                 }
+                ExprKind::IncludedBytes(ref bytes) => hir::ExprKind::Lit(respan(
+                    self.lower_span(e.span),
+                    LitKind::ByteStr(bytes.clone()),
+                )),
                 ExprKind::Cast(ref expr, ref ty) => {
                     let expr = self.lower_expr(expr);
                     let ty =
diff --git a/compiler/rustc_ast_lowering/src/index.rs b/compiler/rustc_ast_lowering/src/index.rs
index 6d7167963433..f1851d7b40ea 100644
--- a/compiler/rustc_ast_lowering/src/index.rs
+++ b/compiler/rustc_ast_lowering/src/index.rs
@@ -112,19 +112,19 @@ impl<'a, 'hir> Visitor<'hir> for NodeCollector<'a, 'hir> {
 
     fn visit_nested_item(&mut self, item: ItemId) {
         debug!("visit_nested_item: {:?}", item);
-        self.insert_nested(item.def_id.def_id);
+        self.insert_nested(item.owner_id.def_id);
     }
 
     fn visit_nested_trait_item(&mut self, item_id: TraitItemId) {
-        self.insert_nested(item_id.def_id.def_id);
+        self.insert_nested(item_id.owner_id.def_id);
     }
 
     fn visit_nested_impl_item(&mut self, item_id: ImplItemId) {
-        self.insert_nested(item_id.def_id.def_id);
+        self.insert_nested(item_id.owner_id.def_id);
     }
 
     fn visit_nested_foreign_item(&mut self, foreign_id: ForeignItemId) {
-        self.insert_nested(foreign_id.def_id.def_id);
+        self.insert_nested(foreign_id.owner_id.def_id);
     }
 
     fn visit_nested_body(&mut self, id: BodyId) {
@@ -143,7 +143,7 @@ impl<'a, 'hir> Visitor<'hir> for NodeCollector<'a, 'hir> {
 
     #[instrument(level = "debug", skip(self))]
     fn visit_item(&mut self, i: &'hir Item<'hir>) {
-        debug_assert_eq!(i.def_id, self.owner);
+        debug_assert_eq!(i.owner_id, self.owner);
         self.with_parent(i.hir_id(), |this| {
             if let ItemKind::Struct(ref struct_def, _) = i.kind {
                 // If this is a tuple or unit-like struct, register the constructor.
@@ -157,7 +157,7 @@ impl<'a, 'hir> Visitor<'hir> for NodeCollector<'a, 'hir> {
 
     #[instrument(level = "debug", skip(self))]
     fn visit_foreign_item(&mut self, fi: &'hir ForeignItem<'hir>) {
-        debug_assert_eq!(fi.def_id, self.owner);
+        debug_assert_eq!(fi.owner_id, self.owner);
         self.with_parent(fi.hir_id(), |this| {
             intravisit::walk_foreign_item(this, fi);
         });
@@ -176,7 +176,7 @@ impl<'a, 'hir> Visitor<'hir> for NodeCollector<'a, 'hir> {
 
     #[instrument(level = "debug", skip(self))]
     fn visit_trait_item(&mut self, ti: &'hir TraitItem<'hir>) {
-        debug_assert_eq!(ti.def_id, self.owner);
+        debug_assert_eq!(ti.owner_id, self.owner);
         self.with_parent(ti.hir_id(), |this| {
             intravisit::walk_trait_item(this, ti);
         });
@@ -184,7 +184,7 @@ impl<'a, 'hir> Visitor<'hir> for NodeCollector<'a, 'hir> {
 
     #[instrument(level = "debug", skip(self))]
     fn visit_impl_item(&mut self, ii: &'hir ImplItem<'hir>) {
-        debug_assert_eq!(ii.def_id, self.owner);
+        debug_assert_eq!(ii.owner_id, self.owner);
         self.with_parent(ii.hir_id(), |this| {
             intravisit::walk_impl_item(this, ii);
         });
diff --git a/compiler/rustc_ast_lowering/src/item.rs b/compiler/rustc_ast_lowering/src/item.rs
index 2117006df10f..76316a574acb 100644
--- a/compiler/rustc_ast_lowering/src/item.rs
+++ b/compiler/rustc_ast_lowering/src/item.rs
@@ -178,7 +178,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
 
     pub(super) fn lower_item_ref(&mut self, i: &Item) -> SmallVec<[hir::ItemId; 1]> {
         let mut node_ids =
-            smallvec![hir::ItemId { def_id: hir::OwnerId { def_id: self.local_def_id(i.id) } }];
+            smallvec![hir::ItemId { owner_id: hir::OwnerId { def_id: self.local_def_id(i.id) } }];
         if let ItemKind::Use(ref use_tree) = &i.kind {
             self.lower_item_id_use_tree(use_tree, i.id, &mut node_ids);
         }
@@ -195,7 +195,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
             UseTreeKind::Nested(ref nested_vec) => {
                 for &(ref nested, id) in nested_vec {
                     vec.push(hir::ItemId {
-                        def_id: hir::OwnerId { def_id: self.local_def_id(id) },
+                        owner_id: hir::OwnerId { def_id: self.local_def_id(id) },
                     });
                     self.lower_item_id_use_tree(nested, id, vec);
                 }
@@ -206,7 +206,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                     iter::zip(self.expect_full_res_from_use(base_id).skip(1), &[id1, id2])
                 {
                     vec.push(hir::ItemId {
-                        def_id: hir::OwnerId { def_id: self.local_def_id(id) },
+                        owner_id: hir::OwnerId { def_id: self.local_def_id(id) },
                     });
                 }
             }
@@ -220,7 +220,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
         let attrs = self.lower_attrs(hir_id, &i.attrs);
         let kind = self.lower_item_kind(i.span, i.id, hir_id, &mut ident, attrs, vis_span, &i.kind);
         let item = hir::Item {
-            def_id: hir_id.expect_owner(),
+            owner_id: hir_id.expect_owner(),
             ident: self.lower_ident(ident),
             kind,
             vis_span,
@@ -562,7 +562,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                         }
 
                         let item = hir::Item {
-                            def_id: hir::OwnerId { def_id: new_id },
+                            owner_id: hir::OwnerId { def_id: new_id },
                             ident: this.lower_ident(ident),
                             kind,
                             vis_span,
@@ -640,7 +640,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                         }
 
                         let item = hir::Item {
-                            def_id: hir::OwnerId { def_id: new_hir_id },
+                            owner_id: hir::OwnerId { def_id: new_hir_id },
                             ident: this.lower_ident(ident),
                             kind,
                             vis_span,
@@ -660,10 +660,10 @@ impl<'hir> LoweringContext<'_, 'hir> {
 
     fn lower_foreign_item(&mut self, i: &ForeignItem) -> &'hir hir::ForeignItem<'hir> {
         let hir_id = self.lower_node_id(i.id);
-        let def_id = hir_id.expect_owner();
+        let owner_id = hir_id.expect_owner();
         self.lower_attrs(hir_id, &i.attrs);
         let item = hir::ForeignItem {
-            def_id,
+            owner_id,
             ident: self.lower_ident(i.ident),
             kind: match i.kind {
                 ForeignItemKind::Fn(box Fn { ref sig, ref generics, .. }) => {
@@ -702,7 +702,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
 
     fn lower_foreign_item_ref(&mut self, i: &ForeignItem) -> hir::ForeignItemRef {
         hir::ForeignItemRef {
-            id: hir::ForeignItemId { def_id: hir::OwnerId { def_id: self.local_def_id(i.id) } },
+            id: hir::ForeignItemId { owner_id: hir::OwnerId { def_id: self.local_def_id(i.id) } },
             ident: self.lower_ident(i.ident),
             span: self.lower_span(i.span),
         }
@@ -845,7 +845,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
 
         self.lower_attrs(hir_id, &i.attrs);
         let item = hir::TraitItem {
-            def_id: trait_item_def_id,
+            owner_id: trait_item_def_id,
             ident: self.lower_ident(i.ident),
             generics,
             kind,
@@ -864,7 +864,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
             }
             AssocItemKind::MacCall(..) => unimplemented!(),
         };
-        let id = hir::TraitItemId { def_id: hir::OwnerId { def_id: self.local_def_id(i.id) } };
+        let id = hir::TraitItemId { owner_id: hir::OwnerId { def_id: self.local_def_id(i.id) } };
         hir::TraitItemRef {
             id,
             ident: self.lower_ident(i.ident),
@@ -931,7 +931,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
         let hir_id = self.lower_node_id(i.id);
         self.lower_attrs(hir_id, &i.attrs);
         let item = hir::ImplItem {
-            def_id: hir_id.expect_owner(),
+            owner_id: hir_id.expect_owner(),
             ident: self.lower_ident(i.ident),
             generics,
             kind,
@@ -944,7 +944,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
 
     fn lower_impl_item_ref(&mut self, i: &AssocItem) -> hir::ImplItemRef {
         hir::ImplItemRef {
-            id: hir::ImplItemId { def_id: hir::OwnerId { def_id: self.local_def_id(i.id) } },
+            id: hir::ImplItemId { owner_id: hir::OwnerId { def_id: self.local_def_id(i.id) } },
             ident: self.lower_ident(i.ident),
             span: self.lower_span(i.span),
             kind: match &i.kind {
diff --git a/compiler/rustc_ast_lowering/src/lib.rs b/compiler/rustc_ast_lowering/src/lib.rs
index 427b71722abc..ff29d15f1b52 100644
--- a/compiler/rustc_ast_lowering/src/lib.rs
+++ b/compiler/rustc_ast_lowering/src/lib.rs
@@ -1574,7 +1574,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
 
         // `impl Trait` now just becomes `Foo<'a, 'b, ..>`.
         hir::TyKind::OpaqueDef(
-            hir::ItemId { def_id: hir::OwnerId { def_id: opaque_ty_def_id } },
+            hir::ItemId { owner_id: hir::OwnerId { def_id: opaque_ty_def_id } },
             lifetimes,
             in_trait,
         )
@@ -1593,7 +1593,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         // Generate an `type Foo = impl Trait;` declaration.
         trace!("registering opaque type with id {:#?}", opaque_ty_id);
         let opaque_ty_item = hir::Item {
-            def_id: hir::OwnerId { def_id: opaque_ty_id },
+            owner_id: hir::OwnerId { def_id: opaque_ty_id },
             ident: Ident::empty(),
             kind: opaque_ty_item_kind,
             vis_span: self.lower_span(span.shrink_to_lo()),
@@ -2044,7 +2044,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         // async fn, so the *type parameters* are inherited.  It's
         // only the lifetime parameters that we must supply.
         let opaque_ty_ref = hir::TyKind::OpaqueDef(
-            hir::ItemId { def_id: hir::OwnerId { def_id: opaque_ty_def_id } },
+            hir::ItemId { owner_id: hir::OwnerId { def_id: opaque_ty_def_id } },
             generic_args,
             in_trait,
         );
diff --git a/compiler/rustc_ast_lowering/src/pat.rs b/compiler/rustc_ast_lowering/src/pat.rs
index 1af1633b5244..7fdfc79164b4 100644
--- a/compiler/rustc_ast_lowering/src/pat.rs
+++ b/compiler/rustc_ast_lowering/src/pat.rs
@@ -323,7 +323,10 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
     // ```
     fn lower_expr_within_pat(&mut self, expr: &Expr, allow_paths: bool) -> &'hir hir::Expr<'hir> {
         match expr.kind {
-            ExprKind::Lit(..) | ExprKind::ConstBlock(..) | ExprKind::Err => {}
+            ExprKind::Lit(..)
+            | ExprKind::ConstBlock(..)
+            | ExprKind::IncludedBytes(..)
+            | ExprKind::Err => {}
             ExprKind::Path(..) if allow_paths => {}
             ExprKind::Unary(UnOp::Neg, ref inner) if matches!(inner.kind, ExprKind::Lit(_)) => {}
             _ => {
diff --git a/compiler/rustc_ast_lowering/src/path.rs b/compiler/rustc_ast_lowering/src/path.rs
index 888776cccac2..c6955741fd4c 100644
--- a/compiler/rustc_ast_lowering/src/path.rs
+++ b/compiler/rustc_ast_lowering/src/path.rs
@@ -191,7 +191,9 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                     self.lower_angle_bracketed_parameter_data(data, param_mode, itctx)
                 }
                 GenericArgs::Parenthesized(ref data) => match parenthesized_generic_args {
-                    ParenthesizedGenericArgs::Ok => self.lower_parenthesized_parameter_data(data),
+                    ParenthesizedGenericArgs::Ok => {
+                        self.lower_parenthesized_parameter_data(data, itctx)
+                    }
                     ParenthesizedGenericArgs::Err => {
                         // Suggest replacing parentheses with angle brackets `Trait(params...)` to `Trait<params...>`
                         let sub = if !data.inputs.is_empty() {
@@ -344,6 +346,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
     fn lower_parenthesized_parameter_data(
         &mut self,
         data: &ParenthesizedArgs,
+        itctx: &ImplTraitContext,
     ) -> (GenericArgsCtor<'hir>, bool) {
         // Switch to `PassThrough` mode for anonymous lifetimes; this
         // means that we permit things like `&Ref<T>`, where `Ref` has
@@ -355,6 +358,17 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
             self.lower_ty_direct(ty, &ImplTraitContext::Disallowed(ImplTraitPosition::FnTraitParam))
         }));
         let output_ty = match output {
+            // Only allow `impl Trait` in return position. i.e.:
+            // ```rust
+            // fn f(_: impl Fn() -> impl Debug) -> impl Fn() -> impl Debug
+            // //      disallowed --^^^^^^^^^^        allowed --^^^^^^^^^^
+            // ```
+            FnRetTy::Ty(ty)
+                if matches!(itctx, ImplTraitContext::ReturnPositionOpaqueTy { .. })
+                    && self.tcx.features().impl_trait_in_fn_trait_return =>
+            {
+                self.lower_ty(&ty, itctx)
+            }
             FnRetTy::Ty(ty) => {
                 self.lower_ty(&ty, &ImplTraitContext::Disallowed(ImplTraitPosition::FnTraitReturn))
             }
diff --git a/compiler/rustc_ast_passes/src/ast_validation.rs b/compiler/rustc_ast_passes/src/ast_validation.rs
index 036643244044..712fb5ac71f9 100644
--- a/compiler/rustc_ast_passes/src/ast_validation.rs
+++ b/compiler/rustc_ast_passes/src/ast_validation.rs
@@ -1051,6 +1051,7 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
 
                     walk_list!(this, visit_assoc_item, items, AssocCtxt::Impl);
                 });
+                walk_list!(self, visit_attribute, &item.attrs);
                 return; // Avoid visiting again.
             }
             ItemKind::Impl(box Impl {
@@ -1168,7 +1169,7 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
                 });
                 walk_list!(self, visit_assoc_item, items, AssocCtxt::Trait);
                 walk_list!(self, visit_attribute, &item.attrs);
-                return;
+                return; // Avoid visiting again
             }
             ItemKind::Mod(unsafety, ref mod_kind) => {
                 if let Unsafe::Yes(span) = unsafety {
diff --git a/compiler/rustc_ast_passes/src/feature_gate.rs b/compiler/rustc_ast_passes/src/feature_gate.rs
index 0f11c1766528..546010135a72 100644
--- a/compiler/rustc_ast_passes/src/feature_gate.rs
+++ b/compiler/rustc_ast_passes/src/feature_gate.rs
@@ -1,7 +1,7 @@
 use rustc_ast as ast;
 use rustc_ast::visit::{self, AssocCtxt, FnCtxt, FnKind, Visitor};
 use rustc_ast::{AssocConstraint, AssocConstraintKind, NodeId};
-use rustc_ast::{PatKind, RangeEnd, VariantData};
+use rustc_ast::{PatKind, RangeEnd};
 use rustc_errors::{struct_span_err, Applicability, StashKey};
 use rustc_feature::{AttributeGate, BuiltinAttribute, Features, GateIssue, BUILTIN_ATTRIBUTE_MAP};
 use rustc_session::parse::{feature_err, feature_err_issue, feature_warn};
@@ -116,46 +116,6 @@ impl<'a> PostExpansionVisitor<'a> {
         }
     }
 
-    fn maybe_report_invalid_custom_discriminants(&self, variants: &[ast::Variant]) {
-        let has_fields = variants.iter().any(|variant| match variant.data {
-            VariantData::Tuple(..) | VariantData::Struct(..) => true,
-            VariantData::Unit(..) => false,
-        });
-
-        let discriminant_spans = variants
-            .iter()
-            .filter(|variant| match variant.data {
-                VariantData::Tuple(..) | VariantData::Struct(..) => false,
-                VariantData::Unit(..) => true,
-            })
-            .filter_map(|variant| variant.disr_expr.as_ref().map(|c| c.value.span))
-            .collect::<Vec<_>>();
-
-        if !discriminant_spans.is_empty() && has_fields {
-            let mut err = feature_err(
-                &self.sess.parse_sess,
-                sym::arbitrary_enum_discriminant,
-                discriminant_spans.clone(),
-                "custom discriminant values are not allowed in enums with tuple or struct variants",
-            );
-            for sp in discriminant_spans {
-                err.span_label(sp, "disallowed custom discriminant");
-            }
-            for variant in variants.iter() {
-                match &variant.data {
-                    VariantData::Struct(..) => {
-                        err.span_label(variant.span, "struct variant defined here");
-                    }
-                    VariantData::Tuple(..) => {
-                        err.span_label(variant.span, "tuple variant defined here");
-                    }
-                    VariantData::Unit(..) => {}
-                }
-            }
-            err.emit();
-        }
-    }
-
     /// Feature gate `impl Trait` inside `type Alias = $type_expr;`.
     fn check_impl_trait(&self, ty: &ast::Ty) {
         struct ImplTraitVisitor<'a> {
@@ -273,26 +233,6 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
                 }
             }
 
-            ast::ItemKind::Enum(ast::EnumDef { ref variants, .. }, ..) => {
-                for variant in variants {
-                    match (&variant.data, &variant.disr_expr) {
-                        (ast::VariantData::Unit(..), _) => {}
-                        (_, Some(disr_expr)) => gate_feature_post!(
-                            &self,
-                            arbitrary_enum_discriminant,
-                            disr_expr.value.span,
-                            "discriminants on non-unit variants are experimental"
-                        ),
-                        _ => {}
-                    }
-                }
-
-                let has_feature = self.features.arbitrary_enum_discriminant;
-                if !has_feature && !i.span.allows_unstable(sym::arbitrary_enum_discriminant) {
-                    self.maybe_report_invalid_custom_discriminants(&variants);
-                }
-            }
-
             ast::ItemKind::Impl(box ast::Impl { polarity, defaultness, ref of_trait, .. }) => {
                 if let ast::ImplPolarity::Negative(span) = polarity {
                     gate_feature_post!(
diff --git a/compiler/rustc_ast_pretty/src/pprust/state/expr.rs b/compiler/rustc_ast_pretty/src/pprust/state/expr.rs
index bcefa8ce0b9c..930276242c3c 100644
--- a/compiler/rustc_ast_pretty/src/pprust/state/expr.rs
+++ b/compiler/rustc_ast_pretty/src/pprust/state/expr.rs
@@ -322,6 +322,10 @@ impl<'a> State<'a> {
             ast::ExprKind::Lit(ref lit) => {
                 self.print_literal(lit);
             }
+            ast::ExprKind::IncludedBytes(ref bytes) => {
+                let lit = ast::Lit::from_included_bytes(bytes, expr.span);
+                self.print_literal(&lit)
+            }
             ast::ExprKind::Cast(ref expr, ref ty) => {
                 let prec = AssocOp::As.precedence() as i8;
                 self.print_expr_maybe_paren(expr, prec);
diff --git a/compiler/rustc_borrowck/src/borrow_set.rs b/compiler/rustc_borrowck/src/borrow_set.rs
index 41279588e633..563ff056ae46 100644
--- a/compiler/rustc_borrowck/src/borrow_set.rs
+++ b/compiler/rustc_borrowck/src/borrow_set.rs
@@ -1,3 +1,5 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 use crate::nll::ToRegionVid;
 use crate::path_utils::allow_two_phase_borrow;
 use crate::place_ext::PlaceExt;
diff --git a/compiler/rustc_borrowck/src/borrowck_errors.rs b/compiler/rustc_borrowck/src/borrowck_errors.rs
index 08ea00d71ef9..01be379120dc 100644
--- a/compiler/rustc_borrowck/src/borrowck_errors.rs
+++ b/compiler/rustc_borrowck/src/borrowck_errors.rs
@@ -8,9 +8,18 @@ impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
     pub(crate) fn cannot_move_when_borrowed(
         &self,
         span: Span,
-        desc: &str,
+        borrow_span: Span,
+        place: &str,
+        borrow_place: &str,
+        value_place: &str,
     ) -> DiagnosticBuilder<'cx, ErrorGuaranteed> {
-        struct_span_err!(self, span, E0505, "cannot move out of {} because it is borrowed", desc,)
+        self.infcx.tcx.sess.create_err(crate::session_diagnostics::MoveBorrow {
+            place,
+            span,
+            borrow_place,
+            value_place,
+            borrow_span,
+        })
     }
 
     pub(crate) fn cannot_use_when_mutably_borrowed(
diff --git a/compiler/rustc_borrowck/src/constraint_generation.rs b/compiler/rustc_borrowck/src/constraint_generation.rs
index f185e402fc6d..11b31c3f1402 100644
--- a/compiler/rustc_borrowck/src/constraint_generation.rs
+++ b/compiler/rustc_borrowck/src/constraint_generation.rs
@@ -1,3 +1,5 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 use rustc_infer::infer::InferCtxt;
 use rustc_middle::mir::visit::TyContext;
 use rustc_middle::mir::visit::Visitor;
diff --git a/compiler/rustc_borrowck/src/constraints/graph.rs b/compiler/rustc_borrowck/src/constraints/graph.rs
index 609fbc2bc151..385f153174c3 100644
--- a/compiler/rustc_borrowck/src/constraints/graph.rs
+++ b/compiler/rustc_borrowck/src/constraints/graph.rs
@@ -163,6 +163,7 @@ impl<'s, 'tcx, D: ConstraintGraphDirecton> Iterator for Edges<'s, 'tcx, D> {
                 span: DUMMY_SP,
                 category: ConstraintCategory::Internal,
                 variance_info: VarianceDiagInfo::default(),
+                from_closure: false,
             })
         } else {
             None
diff --git a/compiler/rustc_borrowck/src/constraints/mod.rs b/compiler/rustc_borrowck/src/constraints/mod.rs
index 58aeb43ef976..84a93e5f72e9 100644
--- a/compiler/rustc_borrowck/src/constraints/mod.rs
+++ b/compiler/rustc_borrowck/src/constraints/mod.rs
@@ -1,3 +1,6 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
+
 use rustc_data_structures::graph::scc::Sccs;
 use rustc_index::vec::IndexVec;
 use rustc_middle::mir::ConstraintCategory;
@@ -92,10 +95,13 @@ pub struct OutlivesConstraint<'tcx> {
     pub span: Span,
 
     /// What caused this constraint?
-    pub category: ConstraintCategory,
+    pub category: ConstraintCategory<'tcx>,
 
     /// Variance diagnostic information
     pub variance_info: VarianceDiagInfo<'tcx>,
+
+    /// If this constraint is promoted from closure requirements.
+    pub from_closure: bool,
 }
 
 impl<'tcx> fmt::Debug for OutlivesConstraint<'tcx> {
diff --git a/compiler/rustc_borrowck/src/consumers.rs b/compiler/rustc_borrowck/src/consumers.rs
index b162095f8a6c..86da767f3227 100644
--- a/compiler/rustc_borrowck/src/consumers.rs
+++ b/compiler/rustc_borrowck/src/consumers.rs
@@ -1,3 +1,5 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 //! This file provides API for compiler consumers.
 
 use rustc_hir::def_id::LocalDefId;
diff --git a/compiler/rustc_borrowck/src/dataflow.rs b/compiler/rustc_borrowck/src/dataflow.rs
index 9f7a4d49989a..8070c0e6710e 100644
--- a/compiler/rustc_borrowck/src/dataflow.rs
+++ b/compiler/rustc_borrowck/src/dataflow.rs
@@ -1,3 +1,5 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 use rustc_data_structures::fx::FxHashMap;
 use rustc_index::bit_set::BitSet;
 use rustc_middle::mir::{self, BasicBlock, Body, Location, Place};
diff --git a/compiler/rustc_borrowck/src/def_use.rs b/compiler/rustc_borrowck/src/def_use.rs
index a5c0d77429de..8e62a0198be4 100644
--- a/compiler/rustc_borrowck/src/def_use.rs
+++ b/compiler/rustc_borrowck/src/def_use.rs
@@ -1,3 +1,5 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 use rustc_middle::mir::visit::{
     MutatingUseContext, NonMutatingUseContext, NonUseContext, PlaceContext,
 };
diff --git a/compiler/rustc_borrowck/src/diagnostics/bound_region_errors.rs b/compiler/rustc_borrowck/src/diagnostics/bound_region_errors.rs
index 02071ed6b366..b99bfda1a51f 100644
--- a/compiler/rustc_borrowck/src/diagnostics/bound_region_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/bound_region_errors.rs
@@ -1,3 +1,6 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
+
 use rustc_errors::{DiagnosticBuilder, ErrorGuaranteed};
 use rustc_infer::infer::canonical::Canonical;
 use rustc_infer::infer::error_reporting::nice_region_error::NiceRegionError;
@@ -5,14 +8,14 @@ use rustc_infer::infer::region_constraints::Constraint;
 use rustc_infer::infer::region_constraints::RegionConstraintData;
 use rustc_infer::infer::RegionVariableOrigin;
 use rustc_infer::infer::{InferCtxt, RegionResolutionError, SubregionOrigin, TyCtxtInferExt as _};
-use rustc_infer::traits::{Normalized, ObligationCause, TraitEngine, TraitEngineExt};
+use rustc_infer::traits::ObligationCause;
 use rustc_middle::ty::error::TypeError;
 use rustc_middle::ty::RegionVid;
 use rustc_middle::ty::UniverseIndex;
 use rustc_middle::ty::{self, Ty, TyCtxt, TypeFoldable};
 use rustc_span::Span;
 use rustc_trait_selection::traits::query::type_op;
-use rustc_trait_selection::traits::{SelectionContext, TraitEngineExt as _};
+use rustc_trait_selection::traits::ObligationCtxt;
 use rustc_traits::{type_op_ascribe_user_type_with_span, type_op_prove_predicate_with_cause};
 
 use std::fmt;
@@ -158,6 +161,7 @@ trait TypeOpInfo<'tcx> {
         error_region: Option<ty::Region<'tcx>>,
     ) -> Option<DiagnosticBuilder<'tcx, ErrorGuaranteed>>;
 
+    #[instrument(level = "debug", skip(self, mbcx))]
     fn report_error(
         &self,
         mbcx: &mut MirBorrowckCtxt<'_, 'tcx>,
@@ -167,6 +171,7 @@ trait TypeOpInfo<'tcx> {
     ) {
         let tcx = mbcx.infcx.tcx;
         let base_universe = self.base_universe();
+        debug!(?base_universe);
 
         let Some(adjusted_universe) =
             placeholder.universe.as_u32().checked_sub(base_universe.as_u32())
@@ -240,9 +245,9 @@ impl<'tcx> TypeOpInfo<'tcx> for PredicateQuery<'tcx> {
     ) -> Option<DiagnosticBuilder<'tcx, ErrorGuaranteed>> {
         let (ref infcx, key, _) =
             mbcx.infcx.tcx.infer_ctxt().build_with_canonical(cause.span, &self.canonical_query);
-        let mut fulfill_cx = <dyn TraitEngine<'_>>::new(infcx.tcx);
-        type_op_prove_predicate_with_cause(infcx, &mut *fulfill_cx, key, cause);
-        try_extract_error_from_fulfill_cx(fulfill_cx, infcx, placeholder_region, error_region)
+        let ocx = ObligationCtxt::new(infcx);
+        type_op_prove_predicate_with_cause(&ocx, key, cause);
+        try_extract_error_from_fulfill_cx(&ocx, placeholder_region, error_region)
     }
 }
 
@@ -281,9 +286,7 @@ where
     ) -> Option<DiagnosticBuilder<'tcx, ErrorGuaranteed>> {
         let (ref infcx, key, _) =
             mbcx.infcx.tcx.infer_ctxt().build_with_canonical(cause.span, &self.canonical_query);
-        let mut fulfill_cx = <dyn TraitEngine<'_>>::new(infcx.tcx);
-
-        let mut selcx = SelectionContext::new(infcx);
+        let ocx = ObligationCtxt::new(infcx);
 
         // FIXME(lqd): Unify and de-duplicate the following with the actual
         // `rustc_traits::type_op::type_op_normalize` query to allow the span we need in the
@@ -292,11 +295,9 @@ where
         // to normalize the `nll/relate_tys/impl-fn-ignore-binder-via-bottom.rs` test. Check
         // after #85499 lands to see if its fixes have erased this difference.
         let (param_env, value) = key.into_parts();
-        let Normalized { value: _, obligations } =
-            rustc_trait_selection::traits::normalize(&mut selcx, param_env, cause, value.value);
-        fulfill_cx.register_predicate_obligations(infcx, obligations);
+        let _ = ocx.normalize(cause, param_env, value.value);
 
-        try_extract_error_from_fulfill_cx(fulfill_cx, infcx, placeholder_region, error_region)
+        try_extract_error_from_fulfill_cx(&ocx, placeholder_region, error_region)
     }
 }
 
@@ -329,9 +330,9 @@ impl<'tcx> TypeOpInfo<'tcx> for AscribeUserTypeQuery<'tcx> {
     ) -> Option<DiagnosticBuilder<'tcx, ErrorGuaranteed>> {
         let (ref infcx, key, _) =
             mbcx.infcx.tcx.infer_ctxt().build_with_canonical(cause.span, &self.canonical_query);
-        let mut fulfill_cx = <dyn TraitEngine<'_>>::new(infcx.tcx);
-        type_op_ascribe_user_type_with_span(infcx, &mut *fulfill_cx, key, Some(cause.span)).ok()?;
-        try_extract_error_from_fulfill_cx(fulfill_cx, infcx, placeholder_region, error_region)
+        let ocx = ObligationCtxt::new(infcx);
+        type_op_ascribe_user_type_with_span(&ocx, key, Some(cause.span)).ok()?;
+        try_extract_error_from_fulfill_cx(&ocx, placeholder_region, error_region)
     }
 }
 
@@ -372,28 +373,28 @@ impl<'tcx> TypeOpInfo<'tcx> for crate::type_check::InstantiateOpaqueType<'tcx> {
     }
 }
 
-#[instrument(skip(fulfill_cx, infcx), level = "debug")]
+#[instrument(skip(ocx), level = "debug")]
 fn try_extract_error_from_fulfill_cx<'tcx>(
-    mut fulfill_cx: Box<dyn TraitEngine<'tcx> + 'tcx>,
-    infcx: &InferCtxt<'tcx>,
+    ocx: &ObligationCtxt<'_, 'tcx>,
     placeholder_region: ty::Region<'tcx>,
     error_region: Option<ty::Region<'tcx>>,
 ) -> Option<DiagnosticBuilder<'tcx, ErrorGuaranteed>> {
     // We generally shouldn't have errors here because the query was
     // already run, but there's no point using `delay_span_bug`
     // when we're going to emit an error here anyway.
-    let _errors = fulfill_cx.select_all_or_error(infcx);
-    let region_constraints = infcx.with_region_constraints(|r| r.clone());
+    let _errors = ocx.select_all_or_error();
+    let region_constraints = ocx.infcx.with_region_constraints(|r| r.clone());
     try_extract_error_from_region_constraints(
-        infcx,
+        ocx.infcx,
         placeholder_region,
         error_region,
         &region_constraints,
-        |vid| infcx.region_var_origin(vid),
-        |vid| infcx.universe_of_region(infcx.tcx.mk_region(ty::ReVar(vid))),
+        |vid| ocx.infcx.region_var_origin(vid),
+        |vid| ocx.infcx.universe_of_region(ocx.infcx.tcx.mk_region(ty::ReVar(vid))),
     )
 }
 
+#[instrument(level = "debug", skip(infcx, region_var_origin, universe_of_region))]
 fn try_extract_error_from_region_constraints<'tcx>(
     infcx: &InferCtxt<'tcx>,
     placeholder_region: ty::Region<'tcx>,
diff --git a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
index 3f5d9fb62066..9e0aa57b2553 100644
--- a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
@@ -23,7 +23,6 @@ use rustc_span::hygiene::DesugaringKind;
 use rustc_span::symbol::sym;
 use rustc_span::{BytePos, Span, Symbol};
 use rustc_trait_selection::infer::InferCtxtExt;
-use rustc_trait_selection::traits::TraitEngineExt as _;
 
 use crate::borrow_set::TwoPhaseActivation;
 use crate::borrowck_errors;
@@ -225,10 +224,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 }
             }
 
-            use_spans.var_span_label_path_only(
-                &mut err,
-                format!("{} occurs due to use{}", desired_action.as_noun(), use_spans.describe()),
-            );
+            use_spans.var_path_only_subdiag(&mut err, desired_action);
 
             if !is_loop_move {
                 err.span_label(
@@ -405,10 +401,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         let used = desired_action.as_general_verb_in_past_tense();
         let mut err =
             struct_span_err!(self, span, E0381, "{used} binding {desc}{isnt_initialized}");
-        use_spans.var_span_label_path_only(
-            &mut err,
-            format!("{} occurs due to use{}", desired_action.as_noun(), use_spans.describe()),
-        );
+        use_spans.var_path_only_subdiag(&mut err, desired_action);
 
         if let InitializationRequiringAction::PartialAssignment
         | InitializationRequiringAction::Assignment = desired_action
@@ -613,24 +606,20 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         else { return; };
         // Try to find predicates on *generic params* that would allow copying `ty`
         let infcx = tcx.infer_ctxt().build();
-        let mut fulfill_cx = <dyn rustc_infer::traits::TraitEngine<'_>>::new(infcx.tcx);
-
         let copy_did = infcx.tcx.lang_items().copy_trait().unwrap();
         let cause = ObligationCause::new(
             span,
             self.mir_hir_id(),
             rustc_infer::traits::ObligationCauseCode::MiscObligation,
         );
-        fulfill_cx.register_bound(
+        let errors = rustc_trait_selection::traits::fully_solve_bound(
             &infcx,
+            cause,
             self.param_env,
             // Erase any region vids from the type, which may not be resolved
             infcx.tcx.erase_regions(ty),
             copy_did,
-            cause,
         );
-        // Select all, including ambiguous predicates
-        let errors = fulfill_cx.select_all_or_error(&infcx);
 
         // Only emit suggestion if all required predicates are on generic
         let predicates: Result<Vec<_>, _> = errors
@@ -678,16 +667,16 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         let move_spans = self.move_spans(place.as_ref(), location);
         let span = move_spans.args_or_use();
 
-        let mut err =
-            self.cannot_move_when_borrowed(span, &self.describe_any_place(place.as_ref()));
-        err.span_label(borrow_span, format!("borrow of {} occurs here", borrow_msg));
-        err.span_label(span, format!("move out of {} occurs here", value_msg));
-
-        borrow_spans.var_span_label_path_only(
-            &mut err,
-            format!("borrow occurs due to use{}", borrow_spans.describe()),
+        let mut err = self.cannot_move_when_borrowed(
+            span,
+            borrow_span,
+            &self.describe_any_place(place.as_ref()),
+            &borrow_msg,
+            &value_msg,
         );
 
+        borrow_spans.var_path_only_subdiag(&mut err, crate::InitializationRequiringAction::Borrow);
+
         move_spans.var_span_label(
             &mut err,
             format!("move occurs due to use{}", move_spans.describe()),
@@ -729,16 +718,15 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             borrow_span,
             &self.describe_any_place(borrow.borrowed_place.as_ref()),
         );
-
-        borrow_spans.var_span_label(
-            &mut err,
-            {
-                let place = &borrow.borrowed_place;
-                let desc_place = self.describe_any_place(place.as_ref());
-                format!("borrow occurs due to use of {}{}", desc_place, borrow_spans.describe())
-            },
-            "mutable",
-        );
+        borrow_spans.var_subdiag(&mut err, Some(borrow.kind), |kind, var_span| {
+            use crate::session_diagnostics::CaptureVarCause::*;
+            let place = &borrow.borrowed_place;
+            let desc_place = self.describe_any_place(place.as_ref());
+            match kind {
+                Some(_) => BorrowUsePlaceGenerator { place: desc_place, var_span },
+                None => BorrowUsePlaceClosure { place: desc_place, var_span },
+            }
+        });
 
         self.explain_why_borrow_contains_point(location, borrow, None)
             .add_explanation_to_diagnostic(
@@ -983,7 +971,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         err: &mut Diagnostic,
         location: Location,
         issued_borrow: &BorrowData<'tcx>,
-        explanation: BorrowExplanation,
+        explanation: BorrowExplanation<'tcx>,
     ) {
         let used_in_call = matches!(
             explanation,
@@ -1333,7 +1321,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         borrow: &BorrowData<'tcx>,
         drop_span: Span,
         borrow_spans: UseSpans<'tcx>,
-        explanation: BorrowExplanation,
+        explanation: BorrowExplanation<'tcx>,
     ) -> DiagnosticBuilder<'cx, ErrorGuaranteed> {
         debug!(
             "report_local_value_does_not_live_long_enough(\
@@ -1539,7 +1527,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         drop_span: Span,
         borrow_spans: UseSpans<'tcx>,
         proper_span: Span,
-        explanation: BorrowExplanation,
+        explanation: BorrowExplanation<'tcx>,
     ) -> DiagnosticBuilder<'cx, ErrorGuaranteed> {
         if let BorrowExplanation::MustBeValidFor { category, span, from_closure: false, .. } =
             explanation
@@ -1556,7 +1544,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         }
 
         let mut err = self.temporary_value_borrowed_for_too_long(proper_span);
-        err.span_label(proper_span, "creates a temporary which is freed while still in use");
+        err.span_label(proper_span, "creates a temporary value which is freed while still in use");
         err.span_label(drop_span, "temporary value is freed at the end of this statement");
 
         match explanation {
@@ -1653,7 +1641,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         borrow: &BorrowData<'tcx>,
         borrow_span: Span,
         return_span: Span,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
         opt_place_desc: Option<&String>,
     ) -> Option<DiagnosticBuilder<'cx, ErrorGuaranteed>> {
         let return_kind = match category {
@@ -1748,7 +1736,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         use_span: UseSpans<'tcx>,
         var_span: Span,
         fr_name: &RegionName,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
         constraint_span: Span,
         captured_var: &str,
     ) -> DiagnosticBuilder<'cx, ErrorGuaranteed> {
diff --git a/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs b/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
index 545237bb3920..582d683dd359 100644
--- a/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
@@ -21,7 +21,7 @@ use crate::{
 use super::{find_use, RegionName, UseSpans};
 
 #[derive(Debug)]
-pub(crate) enum BorrowExplanation {
+pub(crate) enum BorrowExplanation<'tcx> {
     UsedLater(LaterUseKind, Span, Option<Span>),
     UsedLaterInLoop(LaterUseKind, Span, Option<Span>),
     UsedLaterWhenDropped {
@@ -30,7 +30,7 @@ pub(crate) enum BorrowExplanation {
         should_note_order: bool,
     },
     MustBeValidFor {
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
         from_closure: bool,
         span: Span,
         region_name: RegionName,
@@ -49,7 +49,7 @@ pub(crate) enum LaterUseKind {
     Other,
 }
 
-impl<'tcx> BorrowExplanation {
+impl<'tcx> BorrowExplanation<'tcx> {
     pub(crate) fn is_explained(&self) -> bool {
         !matches!(self, BorrowExplanation::Unexplained)
     }
@@ -284,7 +284,7 @@ impl<'tcx> BorrowExplanation {
     fn add_lifetime_bound_suggestion_to_diagnostic(
         &self,
         err: &mut Diagnostic,
-        category: &ConstraintCategory,
+        category: &ConstraintCategory<'tcx>,
         span: Span,
         region_name: &RegionName,
     ) {
@@ -316,7 +316,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         &self,
         borrow_region: RegionVid,
         outlived_region: RegionVid,
-    ) -> (ConstraintCategory, bool, Span, Option<RegionName>, Vec<ExtraConstraintInfo>) {
+    ) -> (ConstraintCategory<'tcx>, bool, Span, Option<RegionName>, Vec<ExtraConstraintInfo>) {
         let (blame_constraint, extra_info) = self.regioncx.best_blame_constraint(
             borrow_region,
             NllRegionVariableOrigin::FreeRegion,
@@ -348,7 +348,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         location: Location,
         borrow: &BorrowData<'tcx>,
         kind_place: Option<(WriteKind, Place<'tcx>)>,
-    ) -> BorrowExplanation {
+    ) -> BorrowExplanation<'tcx> {
         let regioncx = &self.regioncx;
         let body: &Body<'_> = &self.body;
         let tcx = self.infcx.tcx;
diff --git a/compiler/rustc_borrowck/src/diagnostics/find_all_local_uses.rs b/compiler/rustc_borrowck/src/diagnostics/find_all_local_uses.rs
index b3edc35dc364..498e9834354b 100644
--- a/compiler/rustc_borrowck/src/diagnostics/find_all_local_uses.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/find_all_local_uses.rs
@@ -1,3 +1,6 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
+
 use std::collections::BTreeSet;
 
 use rustc_middle::mir::visit::{PlaceContext, Visitor};
diff --git a/compiler/rustc_borrowck/src/diagnostics/find_use.rs b/compiler/rustc_borrowck/src/diagnostics/find_use.rs
index b5a3081e56a7..15f42e26cbf4 100644
--- a/compiler/rustc_borrowck/src/diagnostics/find_use.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/find_use.rs
@@ -1,3 +1,6 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
+
 use std::collections::VecDeque;
 use std::rc::Rc;
 
diff --git a/compiler/rustc_borrowck/src/diagnostics/mod.rs b/compiler/rustc_borrowck/src/diagnostics/mod.rs
index 534d9ecae6e6..7f26af67c71b 100644
--- a/compiler/rustc_borrowck/src/diagnostics/mod.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/mod.rs
@@ -595,11 +595,34 @@ impl UseSpans<'_> {
         }
     }
 
-    // Add a span label to the use of the captured variable, if it exists.
-    // only adds label to the `path_span`
-    pub(super) fn var_span_label_path_only(self, err: &mut Diagnostic, message: impl Into<String>) {
-        if let UseSpans::ClosureUse { path_span, .. } = self {
-            err.span_label(path_span, message);
+    /// Add a span label to the use of the captured variable, if it exists.
+    /// only adds label to the `path_span`
+    pub(super) fn var_path_only_subdiag(
+        self,
+        err: &mut Diagnostic,
+        action: crate::InitializationRequiringAction,
+    ) {
+        use crate::session_diagnostics::CaptureVarPathUseCause::*;
+        use crate::InitializationRequiringAction::*;
+        if let UseSpans::ClosureUse { generator_kind, path_span, .. } = self {
+            match generator_kind {
+                Some(_) => {
+                    err.subdiagnostic(match action {
+                        Borrow => BorrowInGenerator { path_span },
+                        MatchOn | Use => UseInGenerator { path_span },
+                        Assignment => AssignInGenerator { path_span },
+                        PartialAssignment => AssignPartInGenerator { path_span },
+                    });
+                }
+                None => {
+                    err.subdiagnostic(match action {
+                        Borrow => BorrowInClosure { path_span },
+                        MatchOn | Use => UseInClosure { path_span },
+                        Assignment => AssignInClosure { path_span },
+                        PartialAssignment => AssignPartInClosure { path_span },
+                    });
+                }
+            }
         }
     }
 
@@ -623,6 +646,35 @@ impl UseSpans<'_> {
         }
     }
 
+    /// Add a subdiagnostic to the use of the captured variable, if it exists.
+    pub(super) fn var_subdiag(
+        self,
+        err: &mut Diagnostic,
+        kind: Option<rustc_middle::mir::BorrowKind>,
+        f: impl Fn(Option<GeneratorKind>, Span) -> crate::session_diagnostics::CaptureVarCause,
+    ) {
+        use crate::session_diagnostics::CaptureVarKind::*;
+        if let UseSpans::ClosureUse { generator_kind, capture_kind_span, path_span, .. } = self {
+            if capture_kind_span != path_span {
+                err.subdiagnostic(match kind {
+                    Some(kd) => match kd {
+                        rustc_middle::mir::BorrowKind::Shared
+                        | rustc_middle::mir::BorrowKind::Shallow
+                        | rustc_middle::mir::BorrowKind::Unique => {
+                            Immute { kind_span: capture_kind_span }
+                        }
+
+                        rustc_middle::mir::BorrowKind::Mut { .. } => {
+                            Mut { kind_span: capture_kind_span }
+                        }
+                    },
+                    None => Move { kind_span: capture_kind_span },
+                });
+            };
+            err.subdiagnostic(f(generator_kind, path_span));
+        }
+    }
+
     /// Returns `false` if this place is not used in a closure.
     pub(super) fn for_closure(&self) -> bool {
         match *self {
diff --git a/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs b/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
index 8ad40c0aa0a5..7457369aa58c 100644
--- a/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
@@ -1,6 +1,4 @@
-use rustc_errors::{
-    Applicability, Diagnostic, DiagnosticBuilder, EmissionGuarantee, ErrorGuaranteed,
-};
+use rustc_errors::{Applicability, Diagnostic};
 use rustc_hir as hir;
 use rustc_hir::intravisit::Visitor;
 use rustc_hir::Node;
@@ -629,25 +627,20 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
         self.buffer_error(err);
     }
 
-    fn suggest_map_index_mut_alternatives(
-        &self,
-        ty: Ty<'_>,
-        err: &mut DiagnosticBuilder<'_, ErrorGuaranteed>,
-        span: Span,
-    ) {
+    fn suggest_map_index_mut_alternatives(&self, ty: Ty<'tcx>, err: &mut Diagnostic, span: Span) {
         let Some(adt) = ty.ty_adt_def() else { return };
         let did = adt.did();
         if self.infcx.tcx.is_diagnostic_item(sym::HashMap, did)
             || self.infcx.tcx.is_diagnostic_item(sym::BTreeMap, did)
         {
-            struct V<'a, 'b, 'tcx, G: EmissionGuarantee> {
+            struct V<'a, 'tcx> {
                 assign_span: Span,
-                err: &'a mut DiagnosticBuilder<'b, G>,
+                err: &'a mut Diagnostic,
                 ty: Ty<'tcx>,
                 suggested: bool,
             }
-            impl<'a, 'b: 'a, 'hir, 'tcx, G: EmissionGuarantee> Visitor<'hir> for V<'a, 'b, 'tcx, G> {
-                fn visit_stmt(&mut self, stmt: &'hir hir::Stmt<'hir>) {
+            impl<'a, 'tcx> Visitor<'tcx> for V<'a, 'tcx> {
+                fn visit_stmt(&mut self, stmt: &'tcx hir::Stmt<'tcx>) {
                     hir::intravisit::walk_stmt(self, stmt);
                     let expr = match stmt.kind {
                         hir::StmtKind::Semi(expr) | hir::StmtKind::Expr(expr) => expr,
@@ -705,7 +698,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                                     ),
                                     (rv.span.shrink_to_hi(), ")".to_string()),
                                 ],
-                            ].into_iter(),
+                            ],
                             Applicability::MachineApplicable,
                         );
                         self.suggested = true;
diff --git a/compiler/rustc_borrowck/src/diagnostics/outlives_suggestion.rs b/compiler/rustc_borrowck/src/diagnostics/outlives_suggestion.rs
index 245ea07d120b..35c3df768995 100644
--- a/compiler/rustc_borrowck/src/diagnostics/outlives_suggestion.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/outlives_suggestion.rs
@@ -161,7 +161,7 @@ impl OutlivesSuggestionBuilder {
     pub(crate) fn intermediate_suggestion(
         &mut self,
         mbcx: &MirBorrowckCtxt<'_, '_>,
-        errci: &ErrorConstraintInfo,
+        errci: &ErrorConstraintInfo<'_>,
         diag: &mut Diagnostic,
     ) {
         // Emit an intermediate note.
diff --git a/compiler/rustc_borrowck/src/diagnostics/region_errors.rs b/compiler/rustc_borrowck/src/diagnostics/region_errors.rs
index b619537f3176..76f249dac518 100644
--- a/compiler/rustc_borrowck/src/diagnostics/region_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/region_errors.rs
@@ -2,8 +2,7 @@
 #![deny(rustc::diagnostic_outside_of_impl)]
 //! Error reporting machinery for lifetime errors.
 
-use either::Either;
-use rustc_data_structures::fx::FxHashSet;
+use rustc_data_structures::fx::FxIndexSet;
 use rustc_errors::{Applicability, Diagnostic, DiagnosticBuilder, ErrorGuaranteed, MultiSpan};
 use rustc_hir::def_id::DefId;
 use rustc_hir::intravisit::Visitor;
@@ -17,7 +16,7 @@ use rustc_infer::infer::{
     NllRegionVariableOrigin, RelateParamBound,
 };
 use rustc_middle::hir::place::PlaceBase;
-use rustc_middle::mir::{ConstraintCategory, ReturnConstraint, TerminatorKind};
+use rustc_middle::mir::{ConstraintCategory, ReturnConstraint};
 use rustc_middle::ty::subst::InternalSubsts;
 use rustc_middle::ty::Region;
 use rustc_middle::ty::TypeVisitor;
@@ -40,7 +39,7 @@ use crate::{
     MirBorrowckCtxt,
 };
 
-impl ConstraintDescription for ConstraintCategory {
+impl<'tcx> ConstraintDescription for ConstraintCategory<'tcx> {
     fn description(&self) -> &'static str {
         // Must end with a space. Allows for empty names to be provided.
         match self {
@@ -116,7 +115,7 @@ pub(crate) enum RegionErrorKind<'tcx> {
 
 /// Information about the various region constraints involved in a borrow checker error.
 #[derive(Clone, Debug)]
-pub struct ErrorConstraintInfo {
+pub struct ErrorConstraintInfo<'tcx> {
     // fr: outlived_fr
     pub(super) fr: RegionVid,
     pub(super) fr_is_local: bool,
@@ -124,7 +123,7 @@ pub struct ErrorConstraintInfo {
     pub(super) outlived_fr_is_local: bool,
 
     // Category and span for best blame constraint
-    pub(super) category: ConstraintCategory,
+    pub(super) category: ConstraintCategory<'tcx>,
     pub(super) span: Span,
 }
 
@@ -182,7 +181,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                     // Try to convert the lower-bound region into something named we can print for the user.
                     let lower_bound_region = self.to_error_region(type_test.lower_bound);
 
-                    let type_test_span = type_test.locations.span(&self.body);
+                    let type_test_span = type_test.span;
 
                     if let Some(lower_bound_region) = lower_bound_region {
                         let generic_ty = type_test.generic_kind.to_ty(self.infcx.tcx);
@@ -277,7 +276,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
     fn get_impl_ident_and_self_ty_from_trait(
         &self,
         def_id: DefId,
-        trait_objects: &FxHashSet<DefId>,
+        trait_objects: &FxIndexSet<DefId>,
     ) -> Option<(Ident, &'tcx hir::Ty<'tcx>)> {
         let tcx = self.infcx.tcx;
         match tcx.hir().get_if_local(def_id) {
@@ -499,7 +498,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
     /// ```
     fn report_fnmut_error(
         &self,
-        errci: &ErrorConstraintInfo,
+        errci: &ErrorConstraintInfo<'tcx>,
         kind: ReturnConstraint,
     ) -> DiagnosticBuilder<'tcx, ErrorGuaranteed> {
         let ErrorConstraintInfo { outlived_fr, span, .. } = errci;
@@ -572,7 +571,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
     #[instrument(level = "debug", skip(self))]
     fn report_escaping_data_error(
         &self,
-        errci: &ErrorConstraintInfo,
+        errci: &ErrorConstraintInfo<'tcx>,
     ) -> DiagnosticBuilder<'tcx, ErrorGuaranteed> {
         let ErrorConstraintInfo { span, category, .. } = errci;
 
@@ -676,7 +675,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
     /// ```
     fn report_general_error(
         &self,
-        errci: &ErrorConstraintInfo,
+        errci: &ErrorConstraintInfo<'tcx>,
     ) -> DiagnosticBuilder<'tcx, ErrorGuaranteed> {
         let ErrorConstraintInfo {
             fr,
@@ -789,7 +788,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
         diag: &mut Diagnostic,
         f: Region<'tcx>,
         o: Region<'tcx>,
-        category: &ConstraintCategory,
+        category: &ConstraintCategory<'tcx>,
     ) {
         if !o.is_static() {
             return;
@@ -797,12 +796,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
 
         let tcx = self.infcx.tcx;
 
-        let instance =
-            if let ConstraintCategory::CallArgument(location) = category
-                && let Either::Right(term) = self.body.stmt_at(*location)
-                && let TerminatorKind::Call { func, .. } = &term.kind
-        {
-            let func_ty = func.ty(self.body, tcx);
+        let instance = if let ConstraintCategory::CallArgument(Some(func_ty)) = category {
             let (fn_did, substs) = match func_ty.kind() {
                 ty::FnDef(fn_did, substs) => (fn_did, substs),
                 _ => return,
@@ -836,7 +830,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
         };
         debug!(?param);
 
-        let mut visitor = TraitObjectVisitor(FxHashSet::default());
+        let mut visitor = TraitObjectVisitor(FxIndexSet::default());
         visitor.visit_ty(param.param_ty);
 
         let Some((ident, self_ty)) =
@@ -849,7 +843,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
     fn suggest_constrain_dyn_trait_in_impl(
         &self,
         err: &mut Diagnostic,
-        found_dids: &FxHashSet<DefId>,
+        found_dids: &FxIndexSet<DefId>,
         ident: Ident,
         self_ty: &hir::Ty<'_>,
     ) -> bool {
diff --git a/compiler/rustc_borrowck/src/diagnostics/region_name.rs b/compiler/rustc_borrowck/src/diagnostics/region_name.rs
index 4d251cf7ac75..f9741bacd170 100644
--- a/compiler/rustc_borrowck/src/diagnostics/region_name.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/region_name.rs
@@ -251,7 +251,8 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
             .or_else(|| self.give_name_if_anonymous_region_appears_in_upvars(fr))
             .or_else(|| self.give_name_if_anonymous_region_appears_in_output(fr))
             .or_else(|| self.give_name_if_anonymous_region_appears_in_yield_ty(fr))
-            .or_else(|| self.give_name_if_anonymous_region_appears_in_impl_signature(fr));
+            .or_else(|| self.give_name_if_anonymous_region_appears_in_impl_signature(fr))
+            .or_else(|| self.give_name_if_anonymous_region_appears_in_arg_position_impl_trait(fr));
 
         if let Some(ref value) = value {
             self.region_names.try_borrow_mut().unwrap().insert(fr, value.clone());
@@ -354,7 +355,7 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
                     })
                 }
 
-                ty::BoundRegionKind::BrAnon(_) => None,
+                ty::BoundRegionKind::BrAnon(..) => None,
             },
 
             ty::ReLateBound(..) | ty::ReVar(..) | ty::RePlaceholder(..) | ty::ReErased => None,
@@ -869,13 +870,8 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
             return None;
         }
 
-        let mut found = false;
-        tcx.fold_regions(tcx.type_of(region_parent), |r: ty::Region<'tcx>, _| {
-            if *r == ty::ReEarlyBound(region) {
-                found = true;
-            }
-            r
-        });
+        let found = tcx
+            .any_free_region_meets(&tcx.type_of(region_parent), |r| *r == ty::ReEarlyBound(region));
 
         Some(RegionName {
             name: self.synthesize_region_name(),
@@ -888,4 +884,92 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
             ),
         })
     }
+
+    fn give_name_if_anonymous_region_appears_in_arg_position_impl_trait(
+        &self,
+        fr: RegionVid,
+    ) -> Option<RegionName> {
+        let ty::ReEarlyBound(region) = *self.to_error_region(fr)? else {
+            return None;
+        };
+        if region.has_name() {
+            return None;
+        };
+
+        let predicates = self
+            .infcx
+            .tcx
+            .predicates_of(self.body.source.def_id())
+            .instantiate_identity(self.infcx.tcx)
+            .predicates;
+
+        if let Some(upvar_index) = self
+            .regioncx
+            .universal_regions()
+            .defining_ty
+            .upvar_tys()
+            .position(|ty| self.any_param_predicate_mentions(&predicates, ty, region))
+        {
+            let (upvar_name, upvar_span) = self.regioncx.get_upvar_name_and_span_for_region(
+                self.infcx.tcx,
+                &self.upvars,
+                upvar_index,
+            );
+            let region_name = self.synthesize_region_name();
+
+            Some(RegionName {
+                name: region_name,
+                source: RegionNameSource::AnonRegionFromUpvar(upvar_span, upvar_name),
+            })
+        } else if let Some(arg_index) = self
+            .regioncx
+            .universal_regions()
+            .unnormalized_input_tys
+            .iter()
+            .position(|ty| self.any_param_predicate_mentions(&predicates, *ty, region))
+        {
+            let (arg_name, arg_span) = self.regioncx.get_argument_name_and_span_for_region(
+                self.body,
+                &self.local_names,
+                arg_index,
+            );
+            let region_name = self.synthesize_region_name();
+
+            Some(RegionName {
+                name: region_name,
+                source: RegionNameSource::AnonRegionFromArgument(
+                    RegionNameHighlight::CannotMatchHirTy(arg_span, arg_name?.to_string()),
+                ),
+            })
+        } else {
+            None
+        }
+    }
+
+    fn any_param_predicate_mentions(
+        &self,
+        predicates: &[ty::Predicate<'tcx>],
+        ty: Ty<'tcx>,
+        region: ty::EarlyBoundRegion,
+    ) -> bool {
+        let tcx = self.infcx.tcx;
+        ty.walk().any(|arg| {
+            if let ty::GenericArgKind::Type(ty) = arg.unpack()
+                && let ty::Param(_) = ty.kind()
+            {
+                predicates.iter().any(|pred| {
+                    match pred.kind().skip_binder() {
+                        ty::PredicateKind::Trait(data) if data.self_ty() == ty => {}
+                        ty::PredicateKind::Projection(data) if data.projection_ty.self_ty() == ty => {}
+                        _ => return false,
+                    }
+                    tcx.any_free_region_meets(pred, |r| {
+                        *r == ty::ReEarlyBound(region)
+                    })
+                })
+            } else {
+                false
+            }
+        })
+    }
 }
diff --git a/compiler/rustc_borrowck/src/diagnostics/var_name.rs b/compiler/rustc_borrowck/src/diagnostics/var_name.rs
index 9ba29f04b1a9..b385f95b67c6 100644
--- a/compiler/rustc_borrowck/src/diagnostics/var_name.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/var_name.rs
@@ -1,3 +1,6 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
+
 use crate::Upvar;
 use crate::{nll::ToRegionVid, region_infer::RegionInferenceContext};
 use rustc_index::vec::{Idx, IndexVec};
diff --git a/compiler/rustc_borrowck/src/facts.rs b/compiler/rustc_borrowck/src/facts.rs
index 22134d5a71ce..51ed27c167d3 100644
--- a/compiler/rustc_borrowck/src/facts.rs
+++ b/compiler/rustc_borrowck/src/facts.rs
@@ -1,3 +1,5 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 use crate::location::{LocationIndex, LocationTable};
 use crate::BorrowIndex;
 use polonius_engine::AllFacts as PoloniusFacts;
diff --git a/compiler/rustc_borrowck/src/invalidation.rs b/compiler/rustc_borrowck/src/invalidation.rs
index 3157f861d93b..f5317a143aed 100644
--- a/compiler/rustc_borrowck/src/invalidation.rs
+++ b/compiler/rustc_borrowck/src/invalidation.rs
@@ -1,3 +1,5 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 use rustc_data_structures::graph::dominators::Dominators;
 use rustc_middle::mir::visit::Visitor;
 use rustc_middle::mir::{self, BasicBlock, Body, Location, NonDivergingIntrinsic, Place, Rvalue};
diff --git a/compiler/rustc_borrowck/src/lib.rs b/compiler/rustc_borrowck/src/lib.rs
index abfe253d43df..4a4887f19702 100644
--- a/compiler/rustc_borrowck/src/lib.rs
+++ b/compiler/rustc_borrowck/src/lib.rs
@@ -18,6 +18,7 @@ extern crate tracing;
 
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::graph::dominators::Dominators;
+use rustc_data_structures::vec_map::VecMap;
 use rustc_errors::{Diagnostic, DiagnosticBuilder, ErrorGuaranteed};
 use rustc_hir as hir;
 use rustc_hir::def_id::LocalDefId;
@@ -129,6 +130,19 @@ fn mir_borrowck<'tcx>(
 ) -> &'tcx BorrowCheckResult<'tcx> {
     let (input_body, promoted) = tcx.mir_promoted(def);
     debug!("run query mir_borrowck: {}", tcx.def_path_str(def.did.to_def_id()));
+
+    if input_body.borrow().should_skip() {
+        debug!("Skipping borrowck because of injected body");
+        // Let's make up a borrowck result! Fun times!
+        let result = BorrowCheckResult {
+            concrete_opaque_types: VecMap::new(),
+            closure_requirements: None,
+            used_mut_upvars: SmallVec::new(),
+            tainted_by_errors: None,
+        };
+        return tcx.arena.alloc(result);
+    }
+
     let hir_owner = tcx.hir().local_def_id_to_hir_id(def.did).owner;
 
     let infcx =
diff --git a/compiler/rustc_borrowck/src/location.rs b/compiler/rustc_borrowck/src/location.rs
index 877944d3d70c..9fa7e218b1b6 100644
--- a/compiler/rustc_borrowck/src/location.rs
+++ b/compiler/rustc_borrowck/src/location.rs
@@ -1,3 +1,5 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 use rustc_index::vec::{Idx, IndexVec};
 use rustc_middle::mir::{BasicBlock, Body, Location};
 
diff --git a/compiler/rustc_borrowck/src/member_constraints.rs b/compiler/rustc_borrowck/src/member_constraints.rs
index 43253a2aab00..b48f9f97daad 100644
--- a/compiler/rustc_borrowck/src/member_constraints.rs
+++ b/compiler/rustc_borrowck/src/member_constraints.rs
@@ -1,3 +1,5 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 use rustc_data_structures::captures::Captures;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_index::vec::IndexVec;
diff --git a/compiler/rustc_borrowck/src/nll.rs b/compiler/rustc_borrowck/src/nll.rs
index 08fdd28eb01b..f8856b56d140 100644
--- a/compiler/rustc_borrowck/src/nll.rs
+++ b/compiler/rustc_borrowck/src/nll.rs
@@ -1,3 +1,5 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 //! The entry point of the NLL borrow checker.
 
 use rustc_data_structures::vec_map::VecMap;
@@ -242,7 +244,6 @@ pub(crate) fn compute_regions<'cx, 'tcx>(
         mut liveness_constraints,
         outlives_constraints,
         member_constraints,
-        closure_bounds_mapping,
         universe_causes,
         type_tests,
     } = constraints;
@@ -264,7 +265,6 @@ pub(crate) fn compute_regions<'cx, 'tcx>(
         universal_region_relations,
         outlives_constraints,
         member_constraints,
-        closure_bounds_mapping,
         universe_causes,
         type_tests,
         liveness_constraints,
diff --git a/compiler/rustc_borrowck/src/path_utils.rs b/compiler/rustc_borrowck/src/path_utils.rs
index b2c8dfc82c20..f8a99a2699e6 100644
--- a/compiler/rustc_borrowck/src/path_utils.rs
+++ b/compiler/rustc_borrowck/src/path_utils.rs
@@ -1,3 +1,5 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 use crate::borrow_set::{BorrowData, BorrowSet, TwoPhaseActivation};
 use crate::places_conflict;
 use crate::AccessDepth;
diff --git a/compiler/rustc_borrowck/src/place_ext.rs b/compiler/rustc_borrowck/src/place_ext.rs
index 93d202e49a15..9f6b1fdfcb54 100644
--- a/compiler/rustc_borrowck/src/place_ext.rs
+++ b/compiler/rustc_borrowck/src/place_ext.rs
@@ -1,3 +1,5 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 use crate::borrow_set::LocalsStateAtExit;
 use rustc_hir as hir;
 use rustc_middle::mir::ProjectionElem;
diff --git a/compiler/rustc_borrowck/src/places_conflict.rs b/compiler/rustc_borrowck/src/places_conflict.rs
index 0e71efd6f8d3..8a87d1972ebf 100644
--- a/compiler/rustc_borrowck/src/places_conflict.rs
+++ b/compiler/rustc_borrowck/src/places_conflict.rs
@@ -1,3 +1,5 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 use crate::ArtificialField;
 use crate::Overlap;
 use crate::{AccessDepth, Deep, Shallow};
diff --git a/compiler/rustc_borrowck/src/prefixes.rs b/compiler/rustc_borrowck/src/prefixes.rs
index 2b50cbac9a02..6f2813498637 100644
--- a/compiler/rustc_borrowck/src/prefixes.rs
+++ b/compiler/rustc_borrowck/src/prefixes.rs
@@ -1,3 +1,5 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 //! From the NLL RFC: "The deep [aka 'supporting'] prefixes for an
 //! place are formed by stripping away fields and derefs, except that
 //! we stop when we reach the deref of a shared reference. [...] "
diff --git a/compiler/rustc_borrowck/src/region_infer/dump_mir.rs b/compiler/rustc_borrowck/src/region_infer/dump_mir.rs
index fe5193102f95..6524b594e44d 100644
--- a/compiler/rustc_borrowck/src/region_infer/dump_mir.rs
+++ b/compiler/rustc_borrowck/src/region_infer/dump_mir.rs
@@ -1,3 +1,5 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 //! As part of generating the regions, if you enable `-Zdump-mir=nll`,
 //! we will generate an annotated copy of the MIR that includes the
 //! state of region inference. This code handles emitting the region
@@ -74,8 +76,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
         let mut constraints: Vec<_> = self.constraints.outlives().iter().collect();
         constraints.sort_by_key(|c| (c.sup, c.sub));
         for constraint in &constraints {
-            let OutlivesConstraint { sup, sub, locations, category, span, variance_info: _ } =
-                constraint;
+            let OutlivesConstraint { sup, sub, locations, category, span, .. } = constraint;
             let (name, arg) = match locations {
                 Locations::All(span) => {
                     ("All", tcx.sess.source_map().span_to_embeddable_string(*span))
diff --git a/compiler/rustc_borrowck/src/region_infer/graphviz.rs b/compiler/rustc_borrowck/src/region_infer/graphviz.rs
index f31ccd74ca6f..2e15586e03b3 100644
--- a/compiler/rustc_borrowck/src/region_infer/graphviz.rs
+++ b/compiler/rustc_borrowck/src/region_infer/graphviz.rs
@@ -1,3 +1,5 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 //! This module provides linkage between RegionInferenceContext and
 //! `rustc_graphviz` traits, specialized to attaching borrowck analysis
 //! data to rendered labels.
diff --git a/compiler/rustc_borrowck/src/region_infer/mod.rs b/compiler/rustc_borrowck/src/region_infer/mod.rs
index 85b9bde2c819..94e9e05e5d64 100644
--- a/compiler/rustc_borrowck/src/region_infer/mod.rs
+++ b/compiler/rustc_borrowck/src/region_infer/mod.rs
@@ -6,10 +6,9 @@ use rustc_data_structures::frozen::Frozen;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::graph::scc::Sccs;
 use rustc_errors::Diagnostic;
-use rustc_hir::def_id::{DefId, CRATE_DEF_ID};
+use rustc_hir::def_id::CRATE_DEF_ID;
 use rustc_hir::CRATE_HIR_ID;
 use rustc_index::vec::IndexVec;
-use rustc_infer::infer::canonical::QueryOutlivesConstraint;
 use rustc_infer::infer::outlives::test_type_match;
 use rustc_infer::infer::region_constraints::{GenericKind, VarInfos, VerifyBound, VerifyIfEq};
 use rustc_infer::infer::{InferCtxt, NllRegionVariableOrigin, RegionVariableOrigin};
@@ -19,9 +18,7 @@ use rustc_middle::mir::{
 };
 use rustc_middle::traits::ObligationCause;
 use rustc_middle::traits::ObligationCauseCode;
-use rustc_middle::ty::{
-    self, subst::SubstsRef, RegionVid, Ty, TyCtxt, TypeFoldable, TypeVisitable,
-};
+use rustc_middle::ty::{self, RegionVid, Ty, TyCtxt, TypeFoldable, TypeVisitable};
 use rustc_span::Span;
 
 use crate::{
@@ -89,10 +86,6 @@ pub struct RegionInferenceContext<'tcx> {
     /// `member_region_scc`.
     member_constraints_applied: Vec<AppliedMemberConstraint>,
 
-    /// Map closure bounds to a `Span` that should be used for error reporting.
-    closure_bounds_mapping:
-        FxHashMap<Location, FxHashMap<(RegionVid, RegionVid), (ConstraintCategory, Span)>>,
-
     /// Map universe indexes to information on why we created it.
     universe_causes: FxHashMap<ty::UniverseIndex, UniverseInfo<'tcx>>,
 
@@ -221,8 +214,8 @@ pub struct TypeTest<'tcx> {
     /// The region `'x` that the type must outlive.
     pub lower_bound: RegionVid,
 
-    /// Where did this constraint arise and why?
-    pub locations: Locations,
+    /// The span to blame.
+    pub span: Span,
 
     /// A test which, if met by the region `'x`, proves that this type
     /// constraint is satisfied.
@@ -265,10 +258,6 @@ impl<'tcx> RegionInferenceContext<'tcx> {
         universal_region_relations: Frozen<UniversalRegionRelations<'tcx>>,
         outlives_constraints: OutlivesConstraintSet<'tcx>,
         member_constraints_in: MemberConstraintSet<'tcx, RegionVid>,
-        closure_bounds_mapping: FxHashMap<
-            Location,
-            FxHashMap<(RegionVid, RegionVid), (ConstraintCategory, Span)>,
-        >,
         universe_causes: FxHashMap<ty::UniverseIndex, UniverseInfo<'tcx>>,
         type_tests: Vec<TypeTest<'tcx>>,
         liveness_constraints: LivenessValues<RegionVid>,
@@ -310,7 +299,6 @@ impl<'tcx> RegionInferenceContext<'tcx> {
             rev_scc_graph: None,
             member_constraints,
             member_constraints_applied: Vec::new(),
-            closure_bounds_mapping,
             universe_causes,
             scc_universes,
             scc_representatives,
@@ -882,13 +870,13 @@ impl<'tcx> RegionInferenceContext<'tcx> {
             if deduplicate_errors.insert((
                 erased_generic_kind,
                 type_test.lower_bound,
-                type_test.locations,
+                type_test.span,
             )) {
                 debug!(
                     "check_type_test: reporting error for erased_generic_kind={:?}, \
                      lower_bound_region={:?}, \
-                     type_test.locations={:?}",
-                    erased_generic_kind, type_test.lower_bound, type_test.locations,
+                     type_test.span={:?}",
+                    erased_generic_kind, type_test.lower_bound, type_test.span,
                 );
 
                 errors_buffer.push(RegionErrorKind::TypeTestError { type_test: type_test.clone() });
@@ -931,7 +919,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     ) -> bool {
         let tcx = infcx.tcx;
 
-        let TypeTest { generic_kind, lower_bound, locations, verify_bound: _ } = type_test;
+        let TypeTest { generic_kind, lower_bound, span: _, verify_bound: _ } = type_test;
 
         let generic_ty = generic_kind.to_ty(tcx);
         let Some(subject) = self.try_promote_type_test_subject(infcx, generic_ty) else {
@@ -959,7 +947,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
             propagated_outlives_requirements.push(ClosureOutlivesRequirement {
                 subject,
                 outlived_free_region: static_r,
-                blame_span: locations.span(body),
+                blame_span: type_test.span,
                 category: ConstraintCategory::Boring,
             });
 
@@ -1011,7 +999,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
                 let requirement = ClosureOutlivesRequirement {
                     subject,
                     outlived_free_region: upper_bound,
-                    blame_span: locations.span(body),
+                    blame_span: type_test.span,
                     category: ConstraintCategory::Boring,
                 };
                 debug!("try_promote_type_test: pushing {:#?}", requirement);
@@ -1804,25 +1792,13 @@ impl<'tcx> RegionInferenceContext<'tcx> {
         }
     }
 
-    pub(crate) fn retrieve_closure_constraint_info(
-        &self,
-        constraint: OutlivesConstraint<'tcx>,
-    ) -> Option<(ConstraintCategory, Span)> {
-        match constraint.locations {
-            Locations::All(_) => None,
-            Locations::Single(loc) => {
-                self.closure_bounds_mapping[&loc].get(&(constraint.sup, constraint.sub)).copied()
-            }
-        }
-    }
-
     /// Finds a good `ObligationCause` to blame for the fact that `fr1` outlives `fr2`.
     pub(crate) fn find_outlives_blame_span(
         &self,
         fr1: RegionVid,
         fr1_origin: NllRegionVariableOrigin,
         fr2: RegionVid,
-    ) -> (ConstraintCategory, ObligationCause<'tcx>) {
+    ) -> (ConstraintCategory<'tcx>, ObligationCause<'tcx>) {
         let BlameConstraint { category, cause, .. } = self
             .best_blame_constraint(fr1, fr1_origin, |r| self.provides_universal_region(r, fr1, fr2))
             .0;
@@ -1921,6 +1897,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
                     span: p_c.definition_span,
                     category: ConstraintCategory::OpaqueType,
                     variance_info: ty::VarianceDiagInfo::default(),
+                    from_closure: false,
                 };
                 handle_constraint(constraint);
             }
@@ -2066,31 +2043,12 @@ impl<'tcx> RegionInferenceContext<'tcx> {
         // Classify each of the constraints along the path.
         let mut categorized_path: Vec<BlameConstraint<'tcx>> = path
             .iter()
-            .map(|constraint| {
-                let (category, span, from_closure, cause_code) =
-                    if constraint.category == ConstraintCategory::ClosureBounds {
-                        if let Some((category, span)) =
-                            self.retrieve_closure_constraint_info(*constraint)
-                        {
-                            (category, span, true, ObligationCauseCode::MiscObligation)
-                        } else {
-                            (
-                                constraint.category,
-                                constraint.span,
-                                false,
-                                ObligationCauseCode::MiscObligation,
-                            )
-                        }
-                    } else {
-                        (constraint.category, constraint.span, false, cause_code.clone())
-                    };
-                BlameConstraint {
-                    category,
-                    from_closure,
-                    cause: ObligationCause::new(span, CRATE_HIR_ID, cause_code),
-                    variance_info: constraint.variance_info,
-                    outlives_constraint: *constraint,
-                }
+            .map(|constraint| BlameConstraint {
+                category: constraint.category,
+                from_closure: constraint.from_closure,
+                cause: ObligationCause::new(constraint.span, CRATE_HIR_ID, cause_code.clone()),
+                variance_info: constraint.variance_info,
+                outlives_constraint: *constraint,
             })
             .collect();
         debug!("categorized_path={:#?}", categorized_path);
@@ -2274,95 +2232,9 @@ impl<'tcx> RegionDefinition<'tcx> {
     }
 }
 
-pub trait ClosureRegionRequirementsExt<'tcx> {
-    fn apply_requirements(
-        &self,
-        tcx: TyCtxt<'tcx>,
-        closure_def_id: DefId,
-        closure_substs: SubstsRef<'tcx>,
-    ) -> Vec<QueryOutlivesConstraint<'tcx>>;
-}
-
-impl<'tcx> ClosureRegionRequirementsExt<'tcx> for ClosureRegionRequirements<'tcx> {
-    /// Given an instance T of the closure type, this method
-    /// instantiates the "extra" requirements that we computed for the
-    /// closure into the inference context. This has the effect of
-    /// adding new outlives obligations to existing variables.
-    ///
-    /// As described on `ClosureRegionRequirements`, the extra
-    /// requirements are expressed in terms of regionvids that index
-    /// into the free regions that appear on the closure type. So, to
-    /// do this, we first copy those regions out from the type T into
-    /// a vector. Then we can just index into that vector to extract
-    /// out the corresponding region from T and apply the
-    /// requirements.
-    fn apply_requirements(
-        &self,
-        tcx: TyCtxt<'tcx>,
-        closure_def_id: DefId,
-        closure_substs: SubstsRef<'tcx>,
-    ) -> Vec<QueryOutlivesConstraint<'tcx>> {
-        debug!(
-            "apply_requirements(closure_def_id={:?}, closure_substs={:?})",
-            closure_def_id, closure_substs
-        );
-
-        // Extract the values of the free regions in `closure_substs`
-        // into a vector.  These are the regions that we will be
-        // relating to one another.
-        let closure_mapping = &UniversalRegions::closure_mapping(
-            tcx,
-            closure_substs,
-            self.num_external_vids,
-            tcx.typeck_root_def_id(closure_def_id),
-        );
-        debug!("apply_requirements: closure_mapping={:?}", closure_mapping);
-
-        // Create the predicates.
-        self.outlives_requirements
-            .iter()
-            .map(|outlives_requirement| {
-                let outlived_region = closure_mapping[outlives_requirement.outlived_free_region];
-
-                match outlives_requirement.subject {
-                    ClosureOutlivesSubject::Region(region) => {
-                        let region = closure_mapping[region];
-                        debug!(
-                            "apply_requirements: region={:?} \
-                             outlived_region={:?} \
-                             outlives_requirement={:?}",
-                            region, outlived_region, outlives_requirement,
-                        );
-                        (
-                            ty::Binder::dummy(ty::OutlivesPredicate(
-                                region.into(),
-                                outlived_region,
-                            )),
-                            ConstraintCategory::BoringNoLocation,
-                        )
-                    }
-
-                    ClosureOutlivesSubject::Ty(ty) => {
-                        debug!(
-                            "apply_requirements: ty={:?} \
-                             outlived_region={:?} \
-                             outlives_requirement={:?}",
-                            ty, outlived_region, outlives_requirement,
-                        );
-                        (
-                            ty::Binder::dummy(ty::OutlivesPredicate(ty.into(), outlived_region)),
-                            ConstraintCategory::BoringNoLocation,
-                        )
-                    }
-                }
-            })
-            .collect()
-    }
-}
-
 #[derive(Clone, Debug)]
 pub struct BlameConstraint<'tcx> {
-    pub category: ConstraintCategory,
+    pub category: ConstraintCategory<'tcx>,
     pub from_closure: bool,
     pub cause: ObligationCause<'tcx>,
     pub variance_info: ty::VarianceDiagInfo<'tcx>,
diff --git a/compiler/rustc_borrowck/src/region_infer/opaque_types.rs b/compiler/rustc_borrowck/src/region_infer/opaque_types.rs
index 11a57ef26217..dd222485daf2 100644
--- a/compiler/rustc_borrowck/src/region_infer/opaque_types.rs
+++ b/compiler/rustc_borrowck/src/region_infer/opaque_types.rs
@@ -4,7 +4,7 @@ use rustc_hir::def_id::LocalDefId;
 use rustc_hir::OpaqueTyOrigin;
 use rustc_infer::infer::TyCtxtInferExt as _;
 use rustc_infer::infer::{DefiningAnchor, InferCtxt};
-use rustc_infer::traits::{Obligation, ObligationCause, TraitEngine};
+use rustc_infer::traits::{Obligation, ObligationCause};
 use rustc_middle::ty::subst::{GenericArgKind, InternalSubsts};
 use rustc_middle::ty::visit::TypeVisitable;
 use rustc_middle::ty::{
@@ -12,7 +12,7 @@ use rustc_middle::ty::{
 };
 use rustc_span::Span;
 use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt as _;
-use rustc_trait_selection::traits::TraitEngineExt as _;
+use rustc_trait_selection::traits::ObligationCtxt;
 
 use super::RegionInferenceContext;
 
@@ -252,50 +252,45 @@ impl<'tcx> InferCtxtExt<'tcx> for InferCtxt<'tcx> {
         // type-alias-impl-trait/issue-67844-nested-opaque.rs
         let infcx =
             self.tcx.infer_ctxt().with_opaque_type_inference(DefiningAnchor::Bubble).build();
+        let ocx = ObligationCtxt::new(&infcx);
         // Require the hidden type to be well-formed with only the generics of the opaque type.
         // Defining use functions may have more bounds than the opaque type, which is ok, as long as the
         // hidden type is well formed even without those bounds.
         let predicate = ty::Binder::dummy(ty::PredicateKind::WellFormed(definition_ty.into()))
             .to_predicate(infcx.tcx);
-        let mut fulfillment_cx = <dyn TraitEngine<'tcx>>::new(infcx.tcx);
 
         let id_substs = InternalSubsts::identity_for_item(self.tcx, def_id.to_def_id());
 
         // Require that the hidden type actually fulfills all the bounds of the opaque type, even without
         // the bounds that the function supplies.
-        match infcx.register_hidden_type(
-            OpaqueTypeKey { def_id, substs: id_substs },
-            ObligationCause::misc(instantiated_ty.span, body_id),
+        let opaque_ty = self.tcx.mk_opaque(def_id.to_def_id(), id_substs);
+        if let Err(err) = ocx.eq(
+            &ObligationCause::misc(instantiated_ty.span, body_id),
             param_env,
+            opaque_ty,
             definition_ty,
-            origin,
         ) {
-            Ok(infer_ok) => {
-                for obligation in infer_ok.obligations {
-                    fulfillment_cx.register_predicate_obligation(&infcx, obligation);
-                }
-            }
-            Err(err) => {
-                infcx
-                    .err_ctxt()
-                    .report_mismatched_types(
-                        &ObligationCause::misc(instantiated_ty.span, body_id),
-                        self.tcx.mk_opaque(def_id.to_def_id(), id_substs),
-                        definition_ty,
-                        err,
-                    )
-                    .emit();
-            }
+            infcx
+                .err_ctxt()
+                .report_mismatched_types(
+                    &ObligationCause::misc(instantiated_ty.span, body_id),
+                    opaque_ty,
+                    definition_ty,
+                    err,
+                )
+                .emit();
         }
 
-        fulfillment_cx.register_predicate_obligation(
-            &infcx,
-            Obligation::misc(instantiated_ty.span, body_id, param_env, predicate),
-        );
+        ocx.register_obligation(Obligation::misc(
+            instantiated_ty.span,
+            body_id,
+            param_env,
+            predicate,
+        ));
 
         // Check that all obligations are satisfied by the implementation's
         // version.
-        let errors = fulfillment_cx.select_all_or_error(&infcx);
+        let errors = ocx.select_all_or_error();
 
         // This is still required for many(half of the tests in ui/type-alias-impl-trait)
         // tests to pass
@@ -304,8 +299,8 @@ impl<'tcx> InferCtxtExt<'tcx> for InferCtxt<'tcx> {
         if errors.is_empty() {
             definition_ty
         } else {
-            infcx.err_ctxt().report_fulfillment_errors(&errors, None, false);
-            self.tcx.ty_error()
+            let reported = infcx.err_ctxt().report_fulfillment_errors(&errors, None);
+            self.tcx.ty_error_with_guaranteed(reported)
         }
     }
 }
diff --git a/compiler/rustc_borrowck/src/region_infer/reverse_sccs.rs b/compiler/rustc_borrowck/src/region_infer/reverse_sccs.rs
index 1e6798eee3df..167f66460969 100644
--- a/compiler/rustc_borrowck/src/region_infer/reverse_sccs.rs
+++ b/compiler/rustc_borrowck/src/region_infer/reverse_sccs.rs
@@ -1,3 +1,5 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 use crate::constraints::ConstraintSccIndex;
 use crate::RegionInferenceContext;
 use itertools::Itertools;
diff --git a/compiler/rustc_borrowck/src/region_infer/values.rs b/compiler/rustc_borrowck/src/region_infer/values.rs
index de20a4bb465c..7498ddccf196 100644
--- a/compiler/rustc_borrowck/src/region_infer/values.rs
+++ b/compiler/rustc_borrowck/src/region_infer/values.rs
@@ -1,3 +1,5 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 use rustc_data_structures::fx::FxIndexSet;
 use rustc_index::bit_set::SparseBitMatrix;
 use rustc_index::interval::IntervalSet;
diff --git a/compiler/rustc_borrowck/src/renumber.rs b/compiler/rustc_borrowck/src/renumber.rs
index f3023769081f..084754830bdb 100644
--- a/compiler/rustc_borrowck/src/renumber.rs
+++ b/compiler/rustc_borrowck/src/renumber.rs
@@ -1,3 +1,5 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 use rustc_index::vec::IndexVec;
 use rustc_infer::infer::{InferCtxt, NllRegionVariableOrigin};
 use rustc_middle::mir::visit::{MutVisitor, TyContext};
diff --git a/compiler/rustc_borrowck/src/session_diagnostics.rs b/compiler/rustc_borrowck/src/session_diagnostics.rs
index cff3089c397c..577332c0744b 100644
--- a/compiler/rustc_borrowck/src/session_diagnostics.rs
+++ b/compiler/rustc_borrowck/src/session_diagnostics.rs
@@ -49,7 +49,7 @@ pub(crate) struct GenericDoesNotLiveLongEnough {
 #[derive(LintDiagnostic)]
 #[diag(borrowck_var_does_not_need_mut)]
 pub(crate) struct VarNeedNotMut {
-    #[suggestion_short(applicability = "machine-applicable", code = "")]
+    #[suggestion(style = "short", applicability = "machine-applicable", code = "")]
     pub span: Span,
 }
 #[derive(Diagnostic)]
@@ -148,3 +148,95 @@ pub(crate) enum RequireStaticErr {
         multi_span: MultiSpan,
     },
 }
+
+#[derive(Subdiagnostic)]
+pub(crate) enum CaptureVarPathUseCause {
+    #[label(borrowck_borrow_due_to_use_generator)]
+    BorrowInGenerator {
+        #[primary_span]
+        path_span: Span,
+    },
+    #[label(borrowck_use_due_to_use_generator)]
+    UseInGenerator {
+        #[primary_span]
+        path_span: Span,
+    },
+    #[label(borrowck_assign_due_to_use_generator)]
+    AssignInGenerator {
+        #[primary_span]
+        path_span: Span,
+    },
+    #[label(borrowck_assign_part_due_to_use_generator)]
+    AssignPartInGenerator {
+        #[primary_span]
+        path_span: Span,
+    },
+    #[label(borrowck_borrow_due_to_use_closure)]
+    BorrowInClosure {
+        #[primary_span]
+        path_span: Span,
+    },
+    #[label(borrowck_use_due_to_use_closure)]
+    UseInClosure {
+        #[primary_span]
+        path_span: Span,
+    },
+    #[label(borrowck_assign_due_to_use_closure)]
+    AssignInClosure {
+        #[primary_span]
+        path_span: Span,
+    },
+    #[label(borrowck_assign_part_due_to_use_closure)]
+    AssignPartInClosure {
+        #[primary_span]
+        path_span: Span,
+    },
+}
+
+#[derive(Subdiagnostic)]
+pub(crate) enum CaptureVarKind {
+    #[label(borrowck_capture_immute)]
+    Immute {
+        #[primary_span]
+        kind_span: Span,
+    },
+    #[label(borrowck_capture_mut)]
+    Mut {
+        #[primary_span]
+        kind_span: Span,
+    },
+    #[label(borrowck_capture_move)]
+    Move {
+        #[primary_span]
+        kind_span: Span,
+    },
+}
+
+#[derive(Subdiagnostic)]
+pub(crate) enum CaptureVarCause {
+    #[label(borrowck_var_borrow_by_use_place_in_generator)]
+    BorrowUsePlaceGenerator {
+        place: String,
+        #[primary_span]
+        var_span: Span,
+    },
+    #[label(borrowck_var_borrow_by_use_place_in_closure)]
+    BorrowUsePlaceClosure {
+        place: String,
+        #[primary_span]
+        var_span: Span,
+    },
+}
+
+#[derive(Diagnostic)]
+#[diag(borrowck_cannot_move_when_borrowed, code = "E0505")]
+pub(crate) struct MoveBorrow<'a> {
+    pub place: &'a str,
+    pub borrow_place: &'a str,
+    pub value_place: &'a str,
+    #[primary_span]
+    #[label(move_label)]
+    pub span: Span,
+    #[label]
+    pub borrow_span: Span,
+}
diff --git a/compiler/rustc_borrowck/src/type_check/canonical.rs b/compiler/rustc_borrowck/src/type_check/canonical.rs
index 459ecfe17e3e..a581726a15c9 100644
--- a/compiler/rustc_borrowck/src/type_check/canonical.rs
+++ b/compiler/rustc_borrowck/src/type_check/canonical.rs
@@ -28,7 +28,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
     pub(super) fn fully_perform_op<R: fmt::Debug, Op>(
         &mut self,
         locations: Locations,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
         op: Op,
     ) -> Fallible<R>
     where
@@ -85,7 +85,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         &mut self,
         trait_ref: ty::TraitRef<'tcx>,
         locations: Locations,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
     ) {
         self.prove_predicate(
             ty::Binder::dummy(ty::PredicateKind::Trait(ty::TraitPredicate {
@@ -124,7 +124,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         &mut self,
         predicates: impl IntoIterator<Item = impl ToPredicate<'tcx>>,
         locations: Locations,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
     ) {
         for predicate in predicates {
             let predicate = predicate.to_predicate(self.tcx());
@@ -139,7 +139,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         &mut self,
         predicate: ty::Predicate<'tcx>,
         locations: Locations,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
     ) {
         let param_env = self.param_env;
         self.fully_perform_op(
@@ -164,7 +164,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         &mut self,
         value: T,
         location: impl NormalizeLocation,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
     ) -> T
     where
         T: type_op::normalize::Normalizable<'tcx> + fmt::Display + Copy + 'tcx,
diff --git a/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs b/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs
index d7e5a118a2e0..ce7f857e2731 100644
--- a/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs
+++ b/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs
@@ -1,10 +1,10 @@
-use rustc_infer::infer::canonical::QueryOutlivesConstraint;
+use rustc_hir::def_id::DefId;
 use rustc_infer::infer::canonical::QueryRegionConstraints;
 use rustc_infer::infer::outlives::env::RegionBoundPairs;
 use rustc_infer::infer::outlives::obligations::{TypeOutlives, TypeOutlivesDelegate};
 use rustc_infer::infer::region_constraints::{GenericKind, VerifyBound};
 use rustc_infer::infer::{self, InferCtxt, SubregionOrigin};
-use rustc_middle::mir::ConstraintCategory;
+use rustc_middle::mir::{ClosureOutlivesSubject, ClosureRegionRequirements, ConstraintCategory};
 use rustc_middle::ty::subst::GenericArgKind;
 use rustc_middle::ty::TypeFoldable;
 use rustc_middle::ty::{self, TyCtxt};
@@ -37,7 +37,8 @@ pub(crate) struct ConstraintConversion<'a, 'tcx> {
     param_env: ty::ParamEnv<'tcx>,
     locations: Locations,
     span: Span,
-    category: ConstraintCategory,
+    category: ConstraintCategory<'tcx>,
+    from_closure: bool,
     constraints: &'a mut MirTypeckRegionConstraints<'tcx>,
 }
 
@@ -50,7 +51,7 @@ impl<'a, 'tcx> ConstraintConversion<'a, 'tcx> {
         param_env: ty::ParamEnv<'tcx>,
         locations: Locations,
         span: Span,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
         constraints: &'a mut MirTypeckRegionConstraints<'tcx>,
     ) -> Self {
         Self {
@@ -64,6 +65,7 @@ impl<'a, 'tcx> ConstraintConversion<'a, 'tcx> {
             span,
             category,
             constraints,
+            from_closure: false,
         }
     }
 
@@ -81,12 +83,62 @@ impl<'a, 'tcx> ConstraintConversion<'a, 'tcx> {
         }
         self.constraints.member_constraints = tmp;
 
-        for query_constraint in outlives {
-            self.convert(query_constraint);
+        for (predicate, constraint_category) in outlives {
+            // At the moment, we never generate any "higher-ranked"
+            // region constraints like `for<'a> 'a: 'b`. At some point
+            // when we move to universes, we will, and this assertion
+            // will start to fail.
+            let predicate = predicate.no_bound_vars().unwrap_or_else(|| {
+                bug!("query_constraint {:?} contained bound vars", predicate,);
+            });
+
+            self.convert(predicate, *constraint_category);
         }
     }
 
-    fn convert(&mut self, query_constraint: &QueryOutlivesConstraint<'tcx>) {
+    /// Given an instance of the closure type, this method instantiates the "extra" requirements
+    /// that we computed for the closure. This has the effect of adding new outlives obligations
+    /// to existing region variables in `closure_substs`.
+    #[instrument(skip(self), level = "debug")]
+    pub fn apply_closure_requirements(
+        &mut self,
+        closure_requirements: &ClosureRegionRequirements<'tcx>,
+        closure_def_id: DefId,
+        closure_substs: ty::SubstsRef<'tcx>,
+    ) {
+        // Extract the values of the free regions in `closure_substs`
+        // into a vector.  These are the regions that we will be
+        // relating to one another.
+        let closure_mapping = &UniversalRegions::closure_mapping(
+            self.tcx,
+            closure_substs,
+            closure_requirements.num_external_vids,
+            closure_def_id.expect_local(),
+        );
+        debug!(?closure_mapping);
+
+        // Create the predicates.
+        let backup = (self.category, self.span, self.from_closure);
+        self.from_closure = true;
+        for outlives_requirement in &closure_requirements.outlives_requirements {
+            let outlived_region = closure_mapping[outlives_requirement.outlived_free_region];
+            let subject = match outlives_requirement.subject {
+                ClosureOutlivesSubject::Region(re) => closure_mapping[re].into(),
+                ClosureOutlivesSubject::Ty(ty) => ty.into(),
+            };
+
+            self.category = outlives_requirement.category;
+            self.span = outlives_requirement.blame_span;
+            self.convert(ty::OutlivesPredicate(subject, outlived_region), self.category);
+        }
+        (self.category, self.span, self.from_closure) = backup;
+    }
+
+    fn convert(
+        &mut self,
+        predicate: ty::OutlivesPredicate<ty::GenericArg<'tcx>, ty::Region<'tcx>>,
+        constraint_category: ConstraintCategory<'tcx>,
+    ) {
         debug!("generate: constraints at: {:#?}", self.locations);
 
         // Extract out various useful fields we'll need below.
@@ -94,17 +146,7 @@ impl<'a, 'tcx> ConstraintConversion<'a, 'tcx> {
             tcx, region_bound_pairs, implicit_region_bound, param_env, ..
         } = *self;
 
-        // At the moment, we never generate any "higher-ranked"
-        // region constraints like `for<'a> 'a: 'b`. At some point
-        // when we move to universes, we will, and this assertion
-        // will start to fail.
-        let ty::OutlivesPredicate(k1, r2) =
-            query_constraint.0.no_bound_vars().unwrap_or_else(|| {
-                bug!("query_constraint {:?} contained bound vars", query_constraint,);
-            });
-
-        let constraint_category = query_constraint.1;
-
+        let ty::OutlivesPredicate(k1, r2) = predicate;
         match k1.unpack() {
             GenericArgKind::Lifetime(r1) => {
                 let r1_vid = self.to_region_vid(r1);
@@ -127,10 +169,7 @@ impl<'a, 'tcx> ConstraintConversion<'a, 'tcx> {
                 .type_must_outlive(origin, t1, r2, constraint_category);
             }
 
-            GenericArgKind::Const(_) => {
-                // Consts cannot outlive one another, so we
-                // don't need to handle any relations here.
-            }
+            GenericArgKind::Const(_) => unreachable!(),
         }
     }
 
@@ -160,7 +199,7 @@ impl<'a, 'tcx> ConstraintConversion<'a, 'tcx> {
         verify_bound: VerifyBound<'tcx>,
     ) -> TypeTest<'tcx> {
         let lower_bound = self.to_region_vid(region);
-        TypeTest { generic_kind, lower_bound, locations: self.locations, verify_bound }
+        TypeTest { generic_kind, lower_bound, span: self.span, verify_bound }
     }
 
     fn to_region_vid(&mut self, r: ty::Region<'tcx>) -> ty::RegionVid {
@@ -175,7 +214,7 @@ impl<'a, 'tcx> ConstraintConversion<'a, 'tcx> {
         &mut self,
         sup: ty::RegionVid,
         sub: ty::RegionVid,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
     ) {
         let category = match self.category {
             ConstraintCategory::Boring | ConstraintCategory::BoringNoLocation => category,
@@ -188,6 +227,7 @@ impl<'a, 'tcx> ConstraintConversion<'a, 'tcx> {
             sub,
             sup,
             variance_info: ty::VarianceDiagInfo::default(),
+            from_closure: self.from_closure,
         });
     }
 
@@ -203,7 +243,7 @@ impl<'a, 'b, 'tcx> TypeOutlivesDelegate<'tcx> for &'a mut ConstraintConversion<'
         _origin: SubregionOrigin<'tcx>,
         a: ty::Region<'tcx>,
         b: ty::Region<'tcx>,
-        constraint_category: ConstraintCategory,
+        constraint_category: ConstraintCategory<'tcx>,
     ) {
         let b = self.to_region_vid(b);
         let a = self.to_region_vid(a);
diff --git a/compiler/rustc_borrowck/src/type_check/free_region_relations.rs b/compiler/rustc_borrowck/src/type_check/free_region_relations.rs
index 02909592637d..14cfc3613bf0 100644
--- a/compiler/rustc_borrowck/src/type_check/free_region_relations.rs
+++ b/compiler/rustc_borrowck/src/type_check/free_region_relations.rs
@@ -247,12 +247,13 @@ impl<'tcx> UniversalRegionRelationsBuilder<'_, 'tcx> {
                     .and(type_op::normalize::Normalize::new(ty))
                     .fully_perform(self.infcx)
                     .unwrap_or_else(|_| {
-                        self.infcx
+                        let reported = self
+                            .infcx
                             .tcx
                             .sess
                             .delay_span_bug(span, &format!("failed to normalize {:?}", ty));
                         TypeOpOutput {
-                            output: self.infcx.tcx.ty_error(),
+                            output: self.infcx.tcx.ty_error_with_guaranteed(reported),
                             constraints: None,
                             error_info: None,
                         }
diff --git a/compiler/rustc_borrowck/src/type_check/mod.rs b/compiler/rustc_borrowck/src/type_check/mod.rs
index 00cacd515a1e..6ccc29b09c0a 100644
--- a/compiler/rustc_borrowck/src/type_check/mod.rs
+++ b/compiler/rustc_borrowck/src/type_check/mod.rs
@@ -1,3 +1,5 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 //! This pass type-checks the MIR to ensure it is not broken.
 
 use std::rc::Rc;
@@ -27,7 +29,7 @@ use rustc_middle::mir::AssertKind;
 use rustc_middle::mir::*;
 use rustc_middle::ty::adjustment::PointerCast;
 use rustc_middle::ty::cast::CastTy;
-use rustc_middle::ty::subst::{GenericArgKind, SubstsRef, UserSubsts};
+use rustc_middle::ty::subst::{SubstsRef, UserSubsts};
 use rustc_middle::ty::visit::TypeVisitable;
 use rustc_middle::ty::{
     self, Binder, CanonicalUserTypeAnnotation, CanonicalUserTypeAnnotations, Dynamic,
@@ -61,7 +63,7 @@ use crate::{
     region_infer::values::{
         LivenessValues, PlaceholderIndex, PlaceholderIndices, RegionValueElements,
     },
-    region_infer::{ClosureRegionRequirementsExt, TypeTest},
+    region_infer::TypeTest,
     type_check::free_region_relations::{CreateResult, UniversalRegionRelations},
     universal_regions::{DefiningTy, UniversalRegions},
     Upvar,
@@ -144,7 +146,6 @@ pub(crate) fn type_check<'mir, 'tcx>(
         liveness_constraints: LivenessValues::new(elements.clone()),
         outlives_constraints: OutlivesConstraintSet::default(),
         member_constraints: MemberConstraintSet::default(),
-        closure_bounds_mapping: Default::default(),
         type_tests: Vec::default(),
         universe_causes: FxHashMap::default(),
     };
@@ -234,11 +235,11 @@ pub(crate) fn type_check<'mir, 'tcx>(
             let mut hidden_type = infcx.resolve_vars_if_possible(decl.hidden_type);
             trace!("finalized opaque type {:?} to {:#?}", opaque_type_key, hidden_type.ty.kind());
             if hidden_type.has_non_region_infer() {
-                infcx.tcx.sess.delay_span_bug(
+                let reported = infcx.tcx.sess.delay_span_bug(
                     decl.hidden_type.span,
                     &format!("could not resolve {:#?}", hidden_type.ty.kind()),
                 );
-                hidden_type.ty = infcx.tcx.ty_error();
+                hidden_type.ty = infcx.tcx.ty_error_with_guaranteed(reported);
             }
 
             (opaque_type_key, (hidden_type, decl.origin))
@@ -584,8 +585,6 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
         // modify their locations.
         let all_facts = &mut None;
         let mut constraints = Default::default();
-        let mut type_tests = Default::default();
-        let mut closure_bounds = Default::default();
         let mut liveness_constraints =
             LivenessValues::new(Rc::new(RegionValueElements::new(&promoted_body)));
         // Don't try to add borrow_region facts for the promoted MIR
@@ -596,11 +595,6 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
                 &mut this.cx.borrowck_context.constraints.outlives_constraints,
                 &mut constraints,
             );
-            mem::swap(&mut this.cx.borrowck_context.constraints.type_tests, &mut type_tests);
-            mem::swap(
-                &mut this.cx.borrowck_context.constraints.closure_bounds_mapping,
-                &mut closure_bounds,
-            );
             mem::swap(
                 &mut this.cx.borrowck_context.constraints.liveness_constraints,
                 &mut liveness_constraints,
@@ -621,13 +615,6 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
         swap_constraints(self);
 
         let locations = location.to_locations();
-
-        // Use location of promoted const in collected constraints
-        for type_test in type_tests.iter() {
-            let mut type_test = type_test.clone();
-            type_test.locations = locations;
-            self.cx.borrowck_context.constraints.type_tests.push(type_test)
-        }
         for constraint in constraints.outlives().iter() {
             let mut constraint = constraint.clone();
             constraint.locations = locations;
@@ -653,18 +640,6 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
                     .add_element(region, location);
             }
         }
-
-        if !closure_bounds.is_empty() {
-            let combined_bounds_mapping =
-                closure_bounds.into_iter().flat_map(|(_, value)| value).collect();
-            let existing = self
-                .cx
-                .borrowck_context
-                .constraints
-                .closure_bounds_mapping
-                .insert(location, combined_bounds_mapping);
-            assert!(existing.is_none(), "Multiple promoteds/closures at the same location.");
-        }
     }
 
     fn sanitize_projection(
@@ -941,9 +916,6 @@ pub(crate) struct MirTypeckRegionConstraints<'tcx> {
 
     pub(crate) member_constraints: MemberConstraintSet<'tcx, RegionVid>,
 
-    pub(crate) closure_bounds_mapping:
-        FxHashMap<Location, FxHashMap<(RegionVid, RegionVid), (ConstraintCategory, Span)>>,
-
     pub(crate) universe_causes: FxHashMap<ty::UniverseIndex, UniverseInfo<'tcx>>,
 
     pub(crate) type_tests: Vec<TypeTest<'tcx>>,
@@ -1133,7 +1105,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
     fn push_region_constraints(
         &mut self,
         locations: Locations,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
         data: &QueryRegionConstraints<'tcx>,
     ) {
         debug!("constraints generated: {:#?}", data);
@@ -1158,7 +1130,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         sub: Ty<'tcx>,
         sup: Ty<'tcx>,
         locations: Locations,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
     ) -> Fallible<()> {
         // Use this order of parameters because the sup type is usually the
         // "expected" type in diagnostics.
@@ -1171,7 +1143,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         expected: Ty<'tcx>,
         found: Ty<'tcx>,
         locations: Locations,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
     ) -> Fallible<()> {
         self.relate_types(expected, ty::Variance::Invariant, found, locations, category)
     }
@@ -1183,7 +1155,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         v: ty::Variance,
         user_ty: &UserTypeProjection,
         locations: Locations,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
     ) -> Fallible<()> {
         let annotated_type = self.user_type_annotations[user_ty.base].inferred_ty;
         let mut curr_projected_ty = PlaceTy::from_ty(annotated_type);
@@ -1618,12 +1590,19 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
             span_mirbug!(self, term, "call to {:?} with wrong # of args", sig);
         }
 
+        let func_ty = if let TerminatorKind::Call { func, .. } = &term.kind {
+            Some(func.ty(body, self.infcx.tcx))
+        } else {
+            None
+        };
+        debug!(?func_ty);
+
         for (n, (fn_arg, op_arg)) in iter::zip(sig.inputs(), args).enumerate() {
             let op_arg_ty = op_arg.ty(body, self.tcx());
 
             let op_arg_ty = self.normalize(op_arg_ty, term_location);
             let category = if from_hir_call {
-                ConstraintCategory::CallArgument(term_location)
+                ConstraintCategory::CallArgument(self.infcx.tcx.erase_regions(func_ty))
             } else {
                 ConstraintCategory::Boring
             };
@@ -1776,7 +1755,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         // `Sized` bound in no way depends on precise regions, so this
         // shouldn't affect `is_sized`.
         let erased_ty = tcx.erase_regions(ty);
-        if !erased_ty.is_sized(tcx.at(span), self.param_env) {
+        if !erased_ty.is_sized(tcx, self.param_env) {
             // in current MIR construction, all non-control-flow rvalue
             // expressions evaluate through `as_temp` or `into` a return
             // slot or local, so to find all unsized rvalues it is enough
@@ -2555,6 +2534,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
                                 span: location.to_locations().span(body),
                                 category,
                                 variance_info: ty::VarianceDiagInfo::default(),
+                                from_closure: false,
                             });
 
                             match mutbl {
@@ -2672,62 +2652,22 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         substs: SubstsRef<'tcx>,
         location: Location,
     ) -> ty::InstantiatedPredicates<'tcx> {
-        if let Some(ref closure_region_requirements) = tcx.mir_borrowck(def_id).closure_requirements
-        {
-            let closure_constraints = QueryRegionConstraints {
-                outlives: closure_region_requirements.apply_requirements(
-                    tcx,
-                    def_id.to_def_id(),
-                    substs,
-                ),
-
-                // Presently, closures never propagate member
-                // constraints to their parents -- they are enforced
-                // locally.  This is largely a non-issue as member
-                // constraints only come from `-> impl Trait` and
-                // friends which don't appear (thus far...) in
-                // closures.
-                member_constraints: vec![],
-            };
-
-            let bounds_mapping = closure_constraints
-                .outlives
-                .iter()
-                .enumerate()
-                .filter_map(|(idx, constraint)| {
-                    let ty::OutlivesPredicate(k1, r2) =
-                        constraint.0.no_bound_vars().unwrap_or_else(|| {
-                            bug!("query_constraint {:?} contained bound vars", constraint,);
-                        });
-
-                    match k1.unpack() {
-                        GenericArgKind::Lifetime(r1) => {
-                            // constraint is r1: r2
-                            let r1_vid = self.borrowck_context.universal_regions.to_region_vid(r1);
-                            let r2_vid = self.borrowck_context.universal_regions.to_region_vid(r2);
-                            let outlives_requirements =
-                                &closure_region_requirements.outlives_requirements[idx];
-                            Some((
-                                (r1_vid, r2_vid),
-                                (outlives_requirements.category, outlives_requirements.blame_span),
-                            ))
-                        }
-                        GenericArgKind::Type(_) | GenericArgKind::Const(_) => None,
-                    }
-                })
-                .collect();
-
-            let existing = self
-                .borrowck_context
-                .constraints
-                .closure_bounds_mapping
-                .insert(location, bounds_mapping);
-            assert!(existing.is_none(), "Multiple closures at the same location.");
-
-            self.push_region_constraints(
+        if let Some(ref closure_requirements) = tcx.mir_borrowck(def_id).closure_requirements {
+            constraint_conversion::ConstraintConversion::new(
+                self.infcx,
+                self.borrowck_context.universal_regions,
+                self.region_bound_pairs,
+                self.implicit_region_bound,
+                self.param_env,
                 location.to_locations(),
-                ConstraintCategory::ClosureBounds,
-                &closure_constraints,
+                DUMMY_SP,                   // irrelevant; will be overrided.
+                ConstraintCategory::Boring, // same as above.
+                &mut self.borrowck_context.constraints,
+            )
+            .apply_closure_requirements(
+                &closure_requirements,
+                def_id.to_def_id(),
+                substs,
             );
         }
 
diff --git a/compiler/rustc_borrowck/src/type_check/relate_tys.rs b/compiler/rustc_borrowck/src/type_check/relate_tys.rs
index b53360ea61bb..94d510328660 100644
--- a/compiler/rustc_borrowck/src/type_check/relate_tys.rs
+++ b/compiler/rustc_borrowck/src/type_check/relate_tys.rs
@@ -1,6 +1,6 @@
 use rustc_infer::infer::nll_relate::{NormalizationStrategy, TypeRelating, TypeRelatingDelegate};
 use rustc_infer::infer::NllRegionVariableOrigin;
-use rustc_infer::traits::ObligationCause;
+use rustc_infer::traits::PredicateObligations;
 use rustc_middle::mir::ConstraintCategory;
 use rustc_middle::ty::error::TypeError;
 use rustc_middle::ty::relate::TypeRelation;
@@ -28,7 +28,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         v: ty::Variance,
         b: Ty<'tcx>,
         locations: Locations,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
     ) -> Fallible<()> {
         TypeRelating::new(
             self.infcx,
@@ -45,7 +45,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         a: ty::SubstsRef<'tcx>,
         b: ty::SubstsRef<'tcx>,
         locations: Locations,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
     ) -> Fallible<()> {
         TypeRelating::new(
             self.infcx,
@@ -64,7 +64,7 @@ struct NllTypeRelatingDelegate<'me, 'bccx, 'tcx> {
     locations: Locations,
 
     /// What category do we assign the resulting `'a: 'b` relationships?
-    category: ConstraintCategory,
+    category: ConstraintCategory<'tcx>,
 
     /// Information so that error reporting knows what types we are relating
     /// when reporting a bound region error.
@@ -75,7 +75,7 @@ impl<'me, 'bccx, 'tcx> NllTypeRelatingDelegate<'me, 'bccx, 'tcx> {
     fn new(
         type_checker: &'me mut TypeChecker<'bccx, 'tcx>,
         locations: Locations,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
         universe_info: UniverseInfo<'tcx>,
     ) -> Self {
         Self { type_checker, locations, category, universe_info }
@@ -136,6 +136,7 @@ impl<'tcx> TypeRelatingDelegate<'tcx> for NllTypeRelatingDelegate<'_, '_, 'tcx>
                 span: self.locations.span(self.type_checker.body),
                 category: self.category,
                 variance_info: info,
+                from_closure: false,
             },
         );
     }
@@ -155,27 +156,16 @@ impl<'tcx> TypeRelatingDelegate<'tcx> for NllTypeRelatingDelegate<'_, '_, 'tcx>
         true
     }
 
-    fn register_opaque_type(
+    fn register_opaque_type_obligations(
         &mut self,
-        a: Ty<'tcx>,
-        b: Ty<'tcx>,
-        a_is_expected: bool,
+        obligations: PredicateObligations<'tcx>,
     ) -> Result<(), TypeError<'tcx>> {
-        let param_env = self.param_env();
-        let span = self.span();
-        let def_id = self.type_checker.body.source.def_id().expect_local();
-        let body_id = self.type_checker.tcx().hir().local_def_id_to_hir_id(def_id);
-        let cause = ObligationCause::misc(span, body_id);
         self.type_checker
             .fully_perform_op(
                 self.locations,
                 self.category,
                 InstantiateOpaqueType {
-                    obligations: self
-                        .type_checker
-                        .infcx
-                        .handle_opaque_type(a, b, a_is_expected, &cause, param_env)?
-                        .obligations,
+                    obligations,
                     // These fields are filled in during execution of the operation
                     base_universe: None,
                     region_constraints: None,
diff --git a/compiler/rustc_borrowck/src/universal_regions.rs b/compiler/rustc_borrowck/src/universal_regions.rs
index 2beb5e0ab5d2..618da9e32532 100644
--- a/compiler/rustc_borrowck/src/universal_regions.rs
+++ b/compiler/rustc_borrowck/src/universal_regions.rs
@@ -22,7 +22,9 @@ use rustc_hir::{BodyOwnerKind, HirId};
 use rustc_index::vec::{Idx, IndexVec};
 use rustc_infer::infer::{InferCtxt, NllRegionVariableOrigin};
 use rustc_middle::ty::fold::TypeFoldable;
-use rustc_middle::ty::{self, InlineConstSubsts, InlineConstSubstsParts, RegionVid, Ty, TyCtxt};
+use rustc_middle::ty::{
+    self, DefIdTree, InlineConstSubsts, InlineConstSubstsParts, RegionVid, Ty, TyCtxt,
+};
 use rustc_middle::ty::{InternalSubsts, SubstsRef};
 use std::iter;
 
@@ -241,7 +243,7 @@ impl<'tcx> UniversalRegions<'tcx> {
         tcx: TyCtxt<'tcx>,
         closure_substs: SubstsRef<'tcx>,
         expected_num_vars: usize,
-        typeck_root_def_id: DefId,
+        closure_def_id: LocalDefId,
     ) -> IndexVec<RegionVid, ty::Region<'tcx>> {
         let mut region_mapping = IndexVec::with_capacity(expected_num_vars);
         region_mapping.push(tcx.lifetimes.re_static);
@@ -249,7 +251,7 @@ impl<'tcx> UniversalRegions<'tcx> {
             region_mapping.push(fr);
         });
 
-        for_each_late_bound_region_defined_on(tcx, typeck_root_def_id, |r| {
+        for_each_late_bound_region_in_recursive_scope(tcx, tcx.local_parent(closure_def_id), |r| {
             region_mapping.push(r);
         });
 
@@ -339,9 +341,8 @@ impl<'tcx> UniversalRegions<'tcx> {
                 // tests, and the resulting print-outs include def-ids
                 // and other things that are not stable across tests!
                 // So we just include the region-vid. Annoying.
-                let typeck_root_def_id = tcx.typeck_root_def_id(def_id);
-                for_each_late_bound_region_defined_on(tcx, typeck_root_def_id, |r| {
-                    err.note(&format!("late-bound region is {:?}", self.to_region_vid(r),));
+                for_each_late_bound_region_in_recursive_scope(tcx, def_id.expect_local(), |r| {
+                    err.note(&format!("late-bound region is {:?}", self.to_region_vid(r)));
                 });
             }
             DefiningTy::Generator(def_id, substs, _) => {
@@ -354,9 +355,8 @@ impl<'tcx> UniversalRegions<'tcx> {
                 // FIXME: As above, we'd like to print out the region
                 // `r` but doing so is not stable across architectures
                 // and so forth.
-                let typeck_root_def_id = tcx.typeck_root_def_id(def_id);
-                for_each_late_bound_region_defined_on(tcx, typeck_root_def_id, |r| {
-                    err.note(&format!("late-bound region is {:?}", self.to_region_vid(r),));
+                for_each_late_bound_region_in_recursive_scope(tcx, def_id.expect_local(), |r| {
+                    err.note(&format!("late-bound region is {:?}", self.to_region_vid(r)));
                 });
             }
             DefiningTy::FnDef(def_id, substs) => {
@@ -421,13 +421,24 @@ impl<'cx, 'tcx> UniversalRegionsBuilder<'cx, 'tcx> {
             first_extern_index
         } else {
             // If this is a closure, generator, or inline-const, then the late-bound regions from the enclosing
-            // function are actually external regions to us. For example, here, 'a is not local
+            // function/closures are actually external regions to us. For example, here, 'a is not local
             // to the closure c (although it is local to the fn foo):
             // fn foo<'a>() {
             //     let c = || { let x: &'a u32 = ...; }
             // }
-            self.infcx
-                .replace_late_bound_regions_with_nll_infer_vars(self.mir_def.did, &mut indices);
+            for_each_late_bound_region_in_recursive_scope(
+                self.infcx.tcx,
+                self.infcx.tcx.local_parent(self.mir_def.did),
+                |r| {
+                    debug!(?r);
+                    if !indices.indices.contains_key(&r) {
+                        let region_vid = self.infcx.next_nll_region_var(FR);
+                        debug!(?region_vid);
+                        indices.insert_late_bound_region(r, region_vid.to_region_vid());
+                    }
+                },
+            );
+
             // Any regions created during the execution of `defining_ty` or during the above
             // late-bound region replacement are all considered 'extern' regions
             self.infcx.num_region_vars()
@@ -444,12 +455,16 @@ impl<'cx, 'tcx> UniversalRegionsBuilder<'cx, 'tcx> {
             bound_inputs_and_output,
             &mut indices,
         );
-        // Converse of above, if this is a function then the late-bound regions declared on its
-        // signature are local to the fn.
-        if self.mir_def.did.to_def_id() == typeck_root_def_id {
-            self.infcx
-                .replace_late_bound_regions_with_nll_infer_vars(self.mir_def.did, &mut indices);
-        }
+        // Converse of above, if this is a function/closure then the late-bound regions declared on its
+        // signature are local.
+        for_each_late_bound_region_in_item(self.infcx.tcx, self.mir_def.did, |r| {
+            debug!(?r);
+            if !indices.indices.contains_key(&r) {
+                let region_vid = self.infcx.next_nll_region_var(FR);
+                debug!(?region_vid);
+                indices.insert_late_bound_region(r, region_vid.to_region_vid());
+            }
+        });
 
         let (unnormalized_output_ty, mut unnormalized_input_tys) =
             inputs_and_output.split_last().unwrap();
@@ -692,7 +707,13 @@ trait InferCtxtExt<'tcx> {
     where
         T: TypeFoldable<'tcx>;
 
-    fn replace_late_bound_regions_with_nll_infer_vars(
+    fn replace_late_bound_regions_with_nll_infer_vars_in_recursive_scope(
+        &self,
+        mir_def_id: LocalDefId,
+        indices: &mut UniversalRegionIndices<'tcx>,
+    );
+
+    fn replace_late_bound_regions_with_nll_infer_vars_in_item(
         &self,
         mir_def_id: LocalDefId,
         indices: &mut UniversalRegionIndices<'tcx>,
@@ -746,13 +767,28 @@ impl<'tcx> InferCtxtExt<'tcx> for InferCtxt<'tcx> {
     /// set of late-bound regions and checks for any that we have not yet seen, adding them to the
     /// inputs vector.
     #[instrument(skip(self, indices))]
-    fn replace_late_bound_regions_with_nll_infer_vars(
+    fn replace_late_bound_regions_with_nll_infer_vars_in_recursive_scope(
         &self,
         mir_def_id: LocalDefId,
         indices: &mut UniversalRegionIndices<'tcx>,
     ) {
-        let typeck_root_def_id = self.tcx.typeck_root_def_id(mir_def_id.to_def_id());
-        for_each_late_bound_region_defined_on(self.tcx, typeck_root_def_id, |r| {
+        for_each_late_bound_region_in_recursive_scope(self.tcx, mir_def_id, |r| {
+            debug!(?r);
+            if !indices.indices.contains_key(&r) {
+                let region_vid = self.next_nll_region_var(FR);
+                debug!(?region_vid);
+                indices.insert_late_bound_region(r, region_vid.to_region_vid());
+            }
+        });
+    }
+
+    #[instrument(skip(self, indices))]
+    fn replace_late_bound_regions_with_nll_infer_vars_in_item(
+        &self,
+        mir_def_id: LocalDefId,
+        indices: &mut UniversalRegionIndices<'tcx>,
+    ) {
+        for_each_late_bound_region_in_item(self.tcx, mir_def_id, |r| {
             debug!(?r);
             if !indices.indices.contains_key(&r) {
                 let region_vid = self.next_nll_region_var(FR);
@@ -803,21 +839,44 @@ impl<'tcx> UniversalRegionIndices<'tcx> {
     }
 }
 
-/// Iterates over the late-bound regions defined on fn_def_id and
-/// invokes `f` with the liberated form of each one.
-fn for_each_late_bound_region_defined_on<'tcx>(
+/// Iterates over the late-bound regions defined on `mir_def_id` and all of its
+/// parents, up to the typeck root, and invokes `f` with the liberated form
+/// of each one.
+fn for_each_late_bound_region_in_recursive_scope<'tcx>(
     tcx: TyCtxt<'tcx>,
-    fn_def_id: DefId,
+    mut mir_def_id: LocalDefId,
     mut f: impl FnMut(ty::Region<'tcx>),
 ) {
-    if let Some(late_bounds) = tcx.is_late_bound_map(fn_def_id.expect_local()) {
-        for &region_def_id in late_bounds.iter() {
-            let name = tcx.item_name(region_def_id.to_def_id());
-            let liberated_region = tcx.mk_region(ty::ReFree(ty::FreeRegion {
-                scope: fn_def_id,
-                bound_region: ty::BoundRegionKind::BrNamed(region_def_id.to_def_id(), name),
-            }));
-            f(liberated_region);
+    let typeck_root_def_id = tcx.typeck_root_def_id(mir_def_id.to_def_id());
+
+    // Walk up the tree, collecting late-bound regions until we hit the typeck root
+    loop {
+        for_each_late_bound_region_in_item(tcx, mir_def_id, &mut f);
+
+        if mir_def_id.to_def_id() == typeck_root_def_id {
+            break;
+        } else {
+            mir_def_id = tcx.local_parent(mir_def_id);
         }
     }
 }
+
+/// Iterates over the late-bound regions defined on `mir_def_id` and all of its
+/// parents, up to the typeck root, and invokes `f` with the liberated form
+/// of each one.
+fn for_each_late_bound_region_in_item<'tcx>(
+    tcx: TyCtxt<'tcx>,
+    mir_def_id: LocalDefId,
+    mut f: impl FnMut(ty::Region<'tcx>),
+) {
+    if !tcx.def_kind(mir_def_id).is_fn_like() {
+        return;
+    }
+
+    for bound_var in tcx.late_bound_vars(tcx.hir().local_def_id_to_hir_id(mir_def_id)) {
+        let ty::BoundVariableKind::Region(bound_region) = bound_var else { continue; };
+        let liberated_region = tcx
+            .mk_region(ty::ReFree(ty::FreeRegion { scope: mir_def_id.to_def_id(), bound_region }));
+        f(liberated_region);
+    }
+}
diff --git a/compiler/rustc_borrowck/src/used_muts.rs b/compiler/rustc_borrowck/src/used_muts.rs
index 8833753b12c5..e297b1230ea0 100644
--- a/compiler/rustc_borrowck/src/used_muts.rs
+++ b/compiler/rustc_borrowck/src/used_muts.rs
@@ -1,3 +1,5 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 use rustc_data_structures::fx::FxHashSet;
 use rustc_middle::mir::visit::{PlaceContext, Visitor};
 use rustc_middle::mir::{
diff --git a/compiler/rustc_builtin_macros/Cargo.toml b/compiler/rustc_builtin_macros/Cargo.toml
index 6469d0d7b88a..467fa932a156 100644
--- a/compiler/rustc_builtin_macros/Cargo.toml
+++ b/compiler/rustc_builtin_macros/Cargo.toml
@@ -23,5 +23,5 @@ rustc_session = { path = "../rustc_session" }
 rustc_span = { path = "../rustc_span" }
 rustc_target = { path = "../rustc_target" }
 smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
-thin-vec = "0.2.8"
+thin-vec = "0.2.9"
 tracing = "0.1"
diff --git a/compiler/rustc_builtin_macros/src/alloc_error_handler.rs b/compiler/rustc_builtin_macros/src/alloc_error_handler.rs
new file mode 100644
index 000000000000..eaf1b1167cf2
--- /dev/null
+++ b/compiler/rustc_builtin_macros/src/alloc_error_handler.rs
@@ -0,0 +1,104 @@
+use crate::util::check_builtin_macro_attribute;
+
+use rustc_ast::ptr::P;
+use rustc_ast::{self as ast, FnHeader, FnSig, Generics, StmtKind};
+use rustc_ast::{Fn, ItemKind, Stmt, TyKind, Unsafe};
+use rustc_expand::base::{Annotatable, ExtCtxt};
+use rustc_span::symbol::{kw, sym, Ident};
+use rustc_span::Span;
+use thin_vec::thin_vec;
+
+pub fn expand(
+    ecx: &mut ExtCtxt<'_>,
+    _span: Span,
+    meta_item: &ast::MetaItem,
+    item: Annotatable,
+) -> Vec<Annotatable> {
+    check_builtin_macro_attribute(ecx, meta_item, sym::alloc_error_handler);
+
+    let orig_item = item.clone();
+    let not_function = || {
+        ecx.sess
+            .parse_sess
+            .span_diagnostic
+            .span_err(item.span(), "alloc_error_handler must be a function");
+        vec![orig_item.clone()]
+    };
+
+    // Allow using `#[alloc_error_handler]` on an item statement
+    // FIXME - if we get deref patterns, use them to reduce duplication here
+    let (item, is_stmt, sig_span) = match &item {
+        Annotatable::Item(item) => match item.kind {
+            ItemKind::Fn(ref fn_kind) => (item, false, ecx.with_def_site_ctxt(fn_kind.sig.span)),
+            _ => return not_function(),
+        },
+        Annotatable::Stmt(stmt) => match &stmt.kind {
+            StmtKind::Item(item_) => match item_.kind {
+                ItemKind::Fn(ref fn_kind) => {
+                    (item_, true, ecx.with_def_site_ctxt(fn_kind.sig.span))
+                }
+                _ => return not_function(),
+            },
+            _ => return not_function(),
+        },
+        _ => return not_function(),
+    };
+
+    // Generate a bunch of new items using the AllocFnFactory
+    let span = ecx.with_def_site_ctxt(item.span);
+
+    // Generate item statements for the allocator methods.
+    let stmts = vec![generate_handler(ecx, item.ident, span, sig_span)];
+
+    // Generate anonymous constant serving as container for the allocator methods.
+    let const_ty = ecx.ty(sig_span, TyKind::Tup(Vec::new()));
+    let const_body = ecx.expr_block(ecx.block(span, stmts));
+    let const_item = ecx.item_const(span, Ident::new(kw::Underscore, span), const_ty, const_body);
+    let const_item = if is_stmt {
+        Annotatable::Stmt(P(ecx.stmt_item(span, const_item)))
+    } else {
+        Annotatable::Item(const_item)
+    };
+
+    // Return the original item and the new methods.
+    vec![orig_item, const_item]
+}
+
+// #[rustc_std_internal_symbol]
+// unsafe fn __rg_oom(size: usize, align: usize) -> ! {
+//     handler(core::alloc::Layout::from_size_align_unchecked(size, align))
+// }
+fn generate_handler(cx: &ExtCtxt<'_>, handler: Ident, span: Span, sig_span: Span) -> Stmt {
+    let usize = cx.path_ident(span, Ident::new(sym::usize, span));
+    let ty_usize = cx.ty_path(usize);
+    let size = Ident::from_str_and_span("size", span);
+    let align = Ident::from_str_and_span("align", span);
+
+    let layout_new = cx.std_path(&[sym::alloc, sym::Layout, sym::from_size_align_unchecked]);
+    let layout_new = cx.expr_path(cx.path(span, layout_new));
+    let layout =
+        cx.expr_call(span, layout_new, vec![cx.expr_ident(span, size), cx.expr_ident(span, align)]);
+
+    let call = cx.expr_call_ident(sig_span, handler, vec![layout]);
+
+    let never = ast::FnRetTy::Ty(cx.ty(span, TyKind::Never));
+    let params = vec![cx.param(span, size, ty_usize.clone()), cx.param(span, align, ty_usize)];
+    let decl = cx.fn_decl(params, never);
+    let header = FnHeader { unsafety: Unsafe::Yes(span), ..FnHeader::default() };
+    let sig = FnSig { decl, header, span: span };
+
+    let body = Some(cx.block_expr(call));
+    let kind = ItemKind::Fn(Box::new(Fn {
+        defaultness: ast::Defaultness::Final,
+        sig,
+        generics: Generics::default(),
+        body,
+    }));
+
+    let special = sym::rustc_std_internal_symbol;
+    let special = cx.meta_word(span, special);
+    let attrs = thin_vec![cx.attribute(special)];
+
+    let item = cx.item(span, Ident::from_str_and_span("__rg_oom", span), attrs, kind);
+    cx.stmt_item(sig_span, item)
+}
diff --git a/compiler/rustc_builtin_macros/src/assert/context.rs b/compiler/rustc_builtin_macros/src/assert/context.rs
index bb6839360262..f72cd14bea04 100644
--- a/compiler/rustc_builtin_macros/src/assert/context.rs
+++ b/compiler/rustc_builtin_macros/src/assert/context.rs
@@ -303,6 +303,7 @@ impl<'cx, 'a> Context<'cx, 'a> {
             | ExprKind::Field(_, _)
             | ExprKind::ForLoop(_, _, _, _)
             | ExprKind::If(_, _, _)
+            | ExprKind::IncludedBytes(..)
             | ExprKind::InlineAsm(_)
             | ExprKind::Let(_, _, _)
             | ExprKind::Lit(_)
diff --git a/compiler/rustc_builtin_macros/src/cfg_accessible.rs b/compiler/rustc_builtin_macros/src/cfg_accessible.rs
index cb5359dd1e27..86df3c44eb33 100644
--- a/compiler/rustc_builtin_macros/src/cfg_accessible.rs
+++ b/compiler/rustc_builtin_macros/src/cfg_accessible.rs
@@ -34,6 +34,7 @@ impl MultiItemModifier for Expander {
         span: Span,
         meta_item: &ast::MetaItem,
         item: Annotatable,
+        _is_derive_const: bool,
     ) -> ExpandResult<Vec<Annotatable>, Annotatable> {
         let template = AttributeTemplate { list: Some("path"), ..Default::default() };
         let attr = &ecx.attribute(meta_item.clone());
diff --git a/compiler/rustc_builtin_macros/src/cfg_eval.rs b/compiler/rustc_builtin_macros/src/cfg_eval.rs
index 009f3c783d4c..750f1fe121f6 100644
--- a/compiler/rustc_builtin_macros/src/cfg_eval.rs
+++ b/compiler/rustc_builtin_macros/src/cfg_eval.rs
@@ -210,8 +210,15 @@ impl CfgEval<'_, '_> {
 }
 
 impl MutVisitor for CfgEval<'_, '_> {
+    #[instrument(level = "trace", skip(self))]
     fn visit_expr(&mut self, expr: &mut P<ast::Expr>) {
-        self.cfg.configure_expr(expr);
+        self.cfg.configure_expr(expr, false);
+        mut_visit::noop_visit_expr(expr, self);
+    }
+
+    #[instrument(level = "trace", skip(self))]
+    fn visit_method_receiver_expr(&mut self, expr: &mut P<ast::Expr>) {
+        self.cfg.configure_expr(expr, true);
         mut_visit::noop_visit_expr(expr, self);
     }
 
diff --git a/compiler/rustc_builtin_macros/src/concat.rs b/compiler/rustc_builtin_macros/src/concat.rs
index 41f4e8c234d5..01454d0e98e6 100644
--- a/compiler/rustc_builtin_macros/src/concat.rs
+++ b/compiler/rustc_builtin_macros/src/concat.rs
@@ -43,6 +43,9 @@ pub fn expand_concat(
                     has_errors = true;
                 }
             },
+            ast::ExprKind::IncludedBytes(..) => {
+                cx.span_err(e.span, "cannot concatenate a byte string literal")
+            }
             ast::ExprKind::Err => {
                 has_errors = true;
             }
diff --git a/compiler/rustc_builtin_macros/src/concat_bytes.rs b/compiler/rustc_builtin_macros/src/concat_bytes.rs
index 66e86bf21826..4886ca786a58 100644
--- a/compiler/rustc_builtin_macros/src/concat_bytes.rs
+++ b/compiler/rustc_builtin_macros/src/concat_bytes.rs
@@ -108,6 +108,16 @@ fn handle_array_element(
                 None
             }
         },
+        ast::ExprKind::IncludedBytes(..) => {
+            if !*has_errors {
+                cx.struct_span_err(expr.span, "cannot concatenate doubly nested array")
+                    .note("byte strings are treated as arrays of bytes")
+                    .help("try flattening the array")
+                    .emit();
+            }
+            *has_errors = true;
+            None
+        }
         _ => {
             missing_literals.push(expr.span);
             None
@@ -167,6 +177,9 @@ pub fn expand_concat_bytes(
                     has_errors = true;
                 }
             },
+            ast::ExprKind::IncludedBytes(ref bytes) => {
+                accumulator.extend_from_slice(bytes);
+            }
             ast::ExprKind::Err => {
                 has_errors = true;
             }
diff --git a/compiler/rustc_builtin_macros/src/derive.rs b/compiler/rustc_builtin_macros/src/derive.rs
index e0fb7affb349..01f237e6ab5f 100644
--- a/compiler/rustc_builtin_macros/src/derive.rs
+++ b/compiler/rustc_builtin_macros/src/derive.rs
@@ -10,7 +10,7 @@ use rustc_session::Session;
 use rustc_span::symbol::{sym, Ident};
 use rustc_span::Span;
 
-pub(crate) struct Expander;
+pub(crate) struct Expander(pub bool);
 
 impl MultiItemModifier for Expander {
     fn expand(
@@ -19,6 +19,7 @@ impl MultiItemModifier for Expander {
         span: Span,
         meta_item: &ast::MetaItem,
         item: Annotatable,
+        _: bool,
     ) -> ExpandResult<Vec<Annotatable>, Annotatable> {
         let sess = ecx.sess;
         if report_bad_target(sess, &item, span) {
@@ -58,20 +59,20 @@ impl MultiItemModifier for Expander {
                         report_path_args(sess, &meta);
                         meta.path
                     })
-                    .map(|path| (path, dummy_annotatable(), None))
+                    .map(|path| (path, dummy_annotatable(), None, self.0))
                     .collect();
 
                 // Do not configure or clone items unless necessary.
                 match &mut resolutions[..] {
                     [] => {}
-                    [(_, first_item, _), others @ ..] => {
+                    [(_, first_item, ..), others @ ..] => {
                         *first_item = cfg_eval(
                             sess,
                             features,
                             item.clone(),
                             ecx.current_expansion.lint_node_id,
                         );
-                        for (_, item, _) in others {
+                        for (_, item, _, _) in others {
                             *item = first_item.clone();
                         }
                     }
diff --git a/compiler/rustc_builtin_macros/src/deriving/bounds.rs b/compiler/rustc_builtin_macros/src/deriving/bounds.rs
index 7bd344467d03..240167146e1f 100644
--- a/compiler/rustc_builtin_macros/src/deriving/bounds.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/bounds.rs
@@ -1,4 +1,3 @@
-use crate::deriving::generic::ty::*;
 use crate::deriving::generic::*;
 use crate::deriving::path_std;
 
@@ -12,16 +11,17 @@ pub fn expand_deriving_copy(
     mitem: &MetaItem,
     item: &Annotatable,
     push: &mut dyn FnMut(Annotatable),
+    is_const: bool,
 ) {
     let trait_def = TraitDef {
         span,
         path: path_std!(marker::Copy),
         skip_path_as_bound: false,
         additional_bounds: Vec::new(),
-        generics: Bounds::empty(),
         supports_unions: true,
         methods: Vec::new(),
         associated_types: Vec::new(),
+        is_const,
     };
 
     trait_def.expand(cx, mitem, item, push);
diff --git a/compiler/rustc_builtin_macros/src/deriving/clone.rs b/compiler/rustc_builtin_macros/src/deriving/clone.rs
index fa8685f5f4e5..2f19fbcac7d7 100644
--- a/compiler/rustc_builtin_macros/src/deriving/clone.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/clone.rs
@@ -14,6 +14,7 @@ pub fn expand_deriving_clone(
     mitem: &MetaItem,
     item: &Annotatable,
     push: &mut dyn FnMut(Annotatable),
+    is_const: bool,
 ) {
     // The simple form is `fn clone(&self) -> Self { *self }`, possibly with
     // some additional `AssertParamIsClone` assertions.
@@ -74,7 +75,6 @@ pub fn expand_deriving_clone(
         path: path_std!(clone::Clone),
         skip_path_as_bound: false,
         additional_bounds: bounds,
-        generics: Bounds::empty(),
         supports_unions: true,
         methods: vec![MethodDef {
             name: sym::clone,
@@ -87,6 +87,7 @@ pub fn expand_deriving_clone(
             combine_substructure: substructure,
         }],
         associated_types: Vec::new(),
+        is_const,
     };
 
     trait_def.expand_ext(cx, mitem, item, push, is_simple)
diff --git a/compiler/rustc_builtin_macros/src/deriving/cmp/eq.rs b/compiler/rustc_builtin_macros/src/deriving/cmp/eq.rs
index eab67b0d354c..a0b836171bea 100644
--- a/compiler/rustc_builtin_macros/src/deriving/cmp/eq.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/cmp/eq.rs
@@ -15,6 +15,7 @@ pub fn expand_deriving_eq(
     mitem: &MetaItem,
     item: &Annotatable,
     push: &mut dyn FnMut(Annotatable),
+    is_const: bool,
 ) {
     let span = cx.with_def_site_ctxt(span);
     let inline = cx.meta_word(span, sym::inline);
@@ -27,7 +28,6 @@ pub fn expand_deriving_eq(
         path: path_std!(cmp::Eq),
         skip_path_as_bound: false,
         additional_bounds: Vec::new(),
-        generics: Bounds::empty(),
         supports_unions: true,
         methods: vec![MethodDef {
             name: sym::assert_receiver_is_total_eq,
@@ -42,6 +42,7 @@ pub fn expand_deriving_eq(
             })),
         }],
         associated_types: Vec::new(),
+        is_const,
     };
 
     super::inject_impl_of_structural_trait(cx, span, item, path_std!(marker::StructuralEq), push);
diff --git a/compiler/rustc_builtin_macros/src/deriving/cmp/ord.rs b/compiler/rustc_builtin_macros/src/deriving/cmp/ord.rs
index 7f117981a9a2..52780981248b 100644
--- a/compiler/rustc_builtin_macros/src/deriving/cmp/ord.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/cmp/ord.rs
@@ -13,6 +13,7 @@ pub fn expand_deriving_ord(
     mitem: &MetaItem,
     item: &Annotatable,
     push: &mut dyn FnMut(Annotatable),
+    is_const: bool,
 ) {
     let inline = cx.meta_word(span, sym::inline);
     let attrs = thin_vec![cx.attribute(inline)];
@@ -21,7 +22,6 @@ pub fn expand_deriving_ord(
         path: path_std!(cmp::Ord),
         skip_path_as_bound: false,
         additional_bounds: Vec::new(),
-        generics: Bounds::empty(),
         supports_unions: false,
         methods: vec![MethodDef {
             name: sym::cmp,
@@ -34,6 +34,7 @@ pub fn expand_deriving_ord(
             combine_substructure: combine_substructure(Box::new(|a, b, c| cs_cmp(a, b, c))),
         }],
         associated_types: Vec::new(),
+        is_const,
     };
 
     trait_def.expand(cx, mitem, item, push)
diff --git a/compiler/rustc_builtin_macros/src/deriving/cmp/partial_eq.rs b/compiler/rustc_builtin_macros/src/deriving/cmp/partial_eq.rs
index 236cbccaf9fe..34de4a620b46 100644
--- a/compiler/rustc_builtin_macros/src/deriving/cmp/partial_eq.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/cmp/partial_eq.rs
@@ -14,6 +14,7 @@ pub fn expand_deriving_partial_eq(
     mitem: &MetaItem,
     item: &Annotatable,
     push: &mut dyn FnMut(Annotatable),
+    is_const: bool,
 ) {
     fn cs_eq(cx: &mut ExtCtxt<'_>, span: Span, substr: &Substructure<'_>) -> BlockOrExpr {
         let base = true;
@@ -85,10 +86,10 @@ pub fn expand_deriving_partial_eq(
         path: path_std!(cmp::PartialEq),
         skip_path_as_bound: false,
         additional_bounds: Vec::new(),
-        generics: Bounds::empty(),
         supports_unions: false,
         methods,
         associated_types: Vec::new(),
+        is_const,
     };
     trait_def.expand(cx, mitem, item, push)
 }
diff --git a/compiler/rustc_builtin_macros/src/deriving/cmp/partial_ord.rs b/compiler/rustc_builtin_macros/src/deriving/cmp/partial_ord.rs
index 4173403a1b84..6cc8f26df559 100644
--- a/compiler/rustc_builtin_macros/src/deriving/cmp/partial_ord.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/cmp/partial_ord.rs
@@ -13,6 +13,7 @@ pub fn expand_deriving_partial_ord(
     mitem: &MetaItem,
     item: &Annotatable,
     push: &mut dyn FnMut(Annotatable),
+    is_const: bool,
 ) {
     let ordering_ty = Path(path_std!(cmp::Ordering));
     let ret_ty =
@@ -39,10 +40,10 @@ pub fn expand_deriving_partial_ord(
         path: path_std!(cmp::PartialOrd),
         skip_path_as_bound: false,
         additional_bounds: vec![],
-        generics: Bounds::empty(),
         supports_unions: false,
         methods: vec![partial_cmp_def],
         associated_types: Vec::new(),
+        is_const,
     };
     trait_def.expand(cx, mitem, item, push)
 }
diff --git a/compiler/rustc_builtin_macros/src/deriving/debug.rs b/compiler/rustc_builtin_macros/src/deriving/debug.rs
index 2cf614ed9476..544d971b27a5 100644
--- a/compiler/rustc_builtin_macros/src/deriving/debug.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/debug.rs
@@ -13,6 +13,7 @@ pub fn expand_deriving_debug(
     mitem: &MetaItem,
     item: &Annotatable,
     push: &mut dyn FnMut(Annotatable),
+    is_const: bool,
 ) {
     // &mut ::std::fmt::Formatter
     let fmtr = Ref(Box::new(Path(path_std!(fmt::Formatter))), ast::Mutability::Mut);
@@ -22,7 +23,6 @@ pub fn expand_deriving_debug(
         path: path_std!(fmt::Debug),
         skip_path_as_bound: false,
         additional_bounds: Vec::new(),
-        generics: Bounds::empty(),
         supports_unions: false,
         methods: vec![MethodDef {
             name: sym::fmt,
@@ -37,6 +37,7 @@ pub fn expand_deriving_debug(
             })),
         }],
         associated_types: Vec::new(),
+        is_const,
     };
     trait_def.expand(cx, mitem, item, push)
 }
diff --git a/compiler/rustc_builtin_macros/src/deriving/decodable.rs b/compiler/rustc_builtin_macros/src/deriving/decodable.rs
index d669f616802f..6d14875a9832 100644
--- a/compiler/rustc_builtin_macros/src/deriving/decodable.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/decodable.rs
@@ -16,6 +16,7 @@ pub fn expand_deriving_rustc_decodable(
     mitem: &MetaItem,
     item: &Annotatable,
     push: &mut dyn FnMut(Annotatable),
+    is_const: bool,
 ) {
     let krate = sym::rustc_serialize;
     let typaram = sym::__D;
@@ -25,7 +26,6 @@ pub fn expand_deriving_rustc_decodable(
         path: Path::new_(vec![krate, sym::Decodable], vec![], PathKind::Global),
         skip_path_as_bound: false,
         additional_bounds: Vec::new(),
-        generics: Bounds::empty(),
         supports_unions: false,
         methods: vec![MethodDef {
             name: sym::decode,
@@ -55,6 +55,7 @@ pub fn expand_deriving_rustc_decodable(
             })),
         }],
         associated_types: Vec::new(),
+        is_const,
     };
 
     trait_def.expand(cx, mitem, item, push)
diff --git a/compiler/rustc_builtin_macros/src/deriving/default.rs b/compiler/rustc_builtin_macros/src/deriving/default.rs
index 17df9fb279ad..93f297ad88b5 100644
--- a/compiler/rustc_builtin_macros/src/deriving/default.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/default.rs
@@ -16,6 +16,7 @@ pub fn expand_deriving_default(
     mitem: &ast::MetaItem,
     item: &Annotatable,
     push: &mut dyn FnMut(Annotatable),
+    is_const: bool,
 ) {
     item.visit_with(&mut DetectNonVariantDefaultAttr { cx });
 
@@ -26,7 +27,6 @@ pub fn expand_deriving_default(
         path: Path::new(vec![kw::Default, sym::Default]),
         skip_path_as_bound: has_a_default_variant(item),
         additional_bounds: Vec::new(),
-        generics: Bounds::empty(),
         supports_unions: false,
         methods: vec![MethodDef {
             name: kw::Default,
@@ -47,6 +47,7 @@ pub fn expand_deriving_default(
             })),
         }],
         associated_types: Vec::new(),
+        is_const,
     };
     trait_def.expand(cx, mitem, item, push)
 }
diff --git a/compiler/rustc_builtin_macros/src/deriving/encodable.rs b/compiler/rustc_builtin_macros/src/deriving/encodable.rs
index f83f58b97d38..9a46ca815372 100644
--- a/compiler/rustc_builtin_macros/src/deriving/encodable.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/encodable.rs
@@ -100,6 +100,7 @@ pub fn expand_deriving_rustc_encodable(
     mitem: &MetaItem,
     item: &Annotatable,
     push: &mut dyn FnMut(Annotatable),
+    is_const: bool,
 ) {
     let krate = sym::rustc_serialize;
     let typaram = sym::__S;
@@ -109,7 +110,6 @@ pub fn expand_deriving_rustc_encodable(
         path: Path::new_(vec![krate, sym::Encodable], vec![], PathKind::Global),
         skip_path_as_bound: false,
         additional_bounds: Vec::new(),
-        generics: Bounds::empty(),
         supports_unions: false,
         methods: vec![MethodDef {
             name: sym::encode,
@@ -139,6 +139,7 @@ pub fn expand_deriving_rustc_encodable(
             })),
         }],
         associated_types: Vec::new(),
+        is_const,
     };
 
     trait_def.expand(cx, mitem, item, push)
diff --git a/compiler/rustc_builtin_macros/src/deriving/generic/mod.rs b/compiler/rustc_builtin_macros/src/deriving/generic/mod.rs
index 16ee3aa89bb1..f48c49f411ce 100644
--- a/compiler/rustc_builtin_macros/src/deriving/generic/mod.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/generic/mod.rs
@@ -171,7 +171,7 @@ use rustc_ast::{GenericArg, GenericParamKind, VariantData};
 use rustc_attr as attr;
 use rustc_expand::base::{Annotatable, ExtCtxt};
 use rustc_span::symbol::{kw, sym, Ident, Symbol};
-use rustc_span::Span;
+use rustc_span::{Span, DUMMY_SP};
 use std::cell::RefCell;
 use std::iter;
 use std::ops::Not;
@@ -195,15 +195,14 @@ pub struct TraitDef<'a> {
     /// other than the current trait
     pub additional_bounds: Vec<Ty>,
 
-    /// Any extra lifetimes and/or bounds, e.g., `D: serialize::Decoder`
-    pub generics: Bounds,
-
     /// Can this trait be derived for unions?
     pub supports_unions: bool,
 
     pub methods: Vec<MethodDef<'a>>,
 
     pub associated_types: Vec<(Ident, Ty)>,
+
+    pub is_const: bool,
 }
 
 pub struct MethodDef<'a> {
@@ -581,19 +580,21 @@ impl<'a> TraitDef<'a> {
             })
         });
 
-        let Generics { mut params, mut where_clause, .. } =
-            self.generics.to_generics(cx, self.span, type_ident, generics);
+        let mut where_clause = ast::WhereClause::default();
         where_clause.span = generics.where_clause.span;
         let ctxt = self.span.ctxt();
         let span = generics.span.with_ctxt(ctxt);
 
         // Create the generic parameters
-        params.extend(generics.params.iter().map(|param| match &param.kind {
-            GenericParamKind::Lifetime { .. } => param.clone(),
-            GenericParamKind::Type { .. } => {
-                // I don't think this can be moved out of the loop, since
-                // a GenericBound requires an ast id
-                let bounds: Vec<_> =
+        let params: Vec<_> = generics
+            .params
+            .iter()
+            .map(|param| match &param.kind {
+                GenericParamKind::Lifetime { .. } => param.clone(),
+                GenericParamKind::Type { .. } => {
+                    // I don't think this can be moved out of the loop, since
+                    // a GenericBound requires an ast id
+                    let bounds: Vec<_> =
                     // extra restrictions on the generics parameters to the
                     // type being derived upon
                     self.additional_bounds.iter().map(|p| {
@@ -606,21 +607,22 @@ impl<'a> TraitDef<'a> {
                         param.bounds.iter().cloned()
                     ).collect();
 
-                cx.typaram(param.ident.span.with_ctxt(ctxt), param.ident, bounds, None)
-            }
-            GenericParamKind::Const { ty, kw_span, .. } => {
-                let const_nodefault_kind = GenericParamKind::Const {
-                    ty: ty.clone(),
-                    kw_span: kw_span.with_ctxt(ctxt),
+                    cx.typaram(param.ident.span.with_ctxt(ctxt), param.ident, bounds, None)
+                }
+                GenericParamKind::Const { ty, kw_span, .. } => {
+                    let const_nodefault_kind = GenericParamKind::Const {
+                        ty: ty.clone(),
+                        kw_span: kw_span.with_ctxt(ctxt),
 
-                    // We can't have default values inside impl block
-                    default: None,
-                };
-                let mut param_clone = param.clone();
-                param_clone.kind = const_nodefault_kind;
-                param_clone
-            }
-        }));
+                        // We can't have default values inside impl block
+                        default: None,
+                    };
+                    let mut param_clone = param.clone();
+                    param_clone.kind = const_nodefault_kind;
+                    param_clone
+                }
+            })
+            .collect();
 
         // and similarly for where clauses
         where_clause.predicates.extend(generics.where_clause.predicates.iter().map(|clause| {
@@ -730,7 +732,7 @@ impl<'a> TraitDef<'a> {
                 unsafety: ast::Unsafe::No,
                 polarity: ast::ImplPolarity::Positive,
                 defaultness: ast::Defaultness::Final,
-                constness: ast::Const::No,
+                constness: if self.is_const { ast::Const::Yes(DUMMY_SP) } else { ast::Const::No },
                 generics: trait_generics,
                 of_trait: opt_trait_ref,
                 self_ty: self_type,
@@ -1060,18 +1062,15 @@ impl<'a> MethodDef<'a> {
                 trait_.create_struct_field_access_fields(cx, selflike_args, struct_def, true);
             mk_body(cx, selflike_fields)
         } else {
-            // Neither packed nor copy. Need to use ref patterns.
+            // Packed and not copy. Need to use ref patterns.
             let prefixes: Vec<_> =
                 (0..selflike_args.len()).map(|i| format!("__self_{}", i)).collect();
-            let addr_of = always_copy;
-            let selflike_fields =
-                trait_.create_struct_pattern_fields(cx, struct_def, &prefixes, addr_of);
+            let selflike_fields = trait_.create_struct_pattern_fields(cx, struct_def, &prefixes);
             let mut body = mk_body(cx, selflike_fields);
 
             let struct_path = cx.path(span, vec![Ident::new(kw::SelfUpper, type_ident.span)]);
-            let by_ref = ByRef::from(is_packed && !always_copy);
             let patterns =
-                trait_.create_struct_patterns(cx, struct_path, struct_def, &prefixes, by_ref);
+                trait_.create_struct_patterns(cx, struct_path, struct_def, &prefixes, ByRef::Yes);
 
             // Do the let-destructuring.
             let mut stmts: Vec<_> = iter::zip(selflike_args, patterns)
@@ -1252,9 +1251,7 @@ impl<'a> MethodDef<'a> {
                 // A single arm has form (&VariantK, &VariantK, ...) => BodyK
                 // (see "Final wrinkle" note below for why.)
 
-                let addr_of = false; // because enums can't be repr(packed)
-                let fields =
-                    trait_.create_struct_pattern_fields(cx, &variant.data, &prefixes, addr_of);
+                let fields = trait_.create_struct_pattern_fields(cx, &variant.data, &prefixes);
 
                 let sp = variant.span.with_ctxt(trait_.span.ctxt());
                 let variant_path = cx.path(sp, vec![type_ident, variant.ident]);
@@ -1517,15 +1514,13 @@ impl<'a> TraitDef<'a> {
         cx: &mut ExtCtxt<'_>,
         struct_def: &'a VariantData,
         prefixes: &[String],
-        addr_of: bool,
     ) -> Vec<FieldInfo> {
         self.create_fields(struct_def, |i, _struct_field, sp| {
             prefixes
                 .iter()
                 .map(|prefix| {
                     let ident = self.mk_pattern_ident(prefix, i);
-                    let expr = cx.expr_path(cx.path_ident(sp, ident));
-                    if addr_of { cx.expr_addr_of(sp, expr) } else { expr }
+                    cx.expr_path(cx.path_ident(sp, ident))
                 })
                 .collect()
         })
diff --git a/compiler/rustc_builtin_macros/src/deriving/hash.rs b/compiler/rustc_builtin_macros/src/deriving/hash.rs
index 6e9d5f08b944..c136bb7141ab 100644
--- a/compiler/rustc_builtin_macros/src/deriving/hash.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/hash.rs
@@ -13,6 +13,7 @@ pub fn expand_deriving_hash(
     mitem: &MetaItem,
     item: &Annotatable,
     push: &mut dyn FnMut(Annotatable),
+    is_const: bool,
 ) {
     let path = Path::new_(pathvec_std!(hash::Hash), vec![], PathKind::Std);
 
@@ -24,7 +25,6 @@ pub fn expand_deriving_hash(
         path,
         skip_path_as_bound: false,
         additional_bounds: Vec::new(),
-        generics: Bounds::empty(),
         supports_unions: false,
         methods: vec![MethodDef {
             name: sym::hash,
@@ -39,6 +39,7 @@ pub fn expand_deriving_hash(
             })),
         }],
         associated_types: Vec::new(),
+        is_const,
     };
 
     hash_trait_def.expand(cx, mitem, item, push);
diff --git a/compiler/rustc_builtin_macros/src/deriving/mod.rs b/compiler/rustc_builtin_macros/src/deriving/mod.rs
index ee346047a0bc..73a1df5d426d 100644
--- a/compiler/rustc_builtin_macros/src/deriving/mod.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/mod.rs
@@ -38,9 +38,10 @@ pub mod partial_ord;
 
 pub mod generic;
 
-pub(crate) struct BuiltinDerive(
-    pub(crate) fn(&mut ExtCtxt<'_>, Span, &MetaItem, &Annotatable, &mut dyn FnMut(Annotatable)),
-);
+pub(crate) type BuiltinDeriveFn =
+    fn(&mut ExtCtxt<'_>, Span, &MetaItem, &Annotatable, &mut dyn FnMut(Annotatable), bool);
+
+pub(crate) struct BuiltinDerive(pub(crate) BuiltinDeriveFn);
 
 impl MultiItemModifier for BuiltinDerive {
     fn expand(
@@ -49,6 +50,7 @@ impl MultiItemModifier for BuiltinDerive {
         span: Span,
         meta_item: &MetaItem,
         item: Annotatable,
+        is_derive_const: bool,
     ) -> ExpandResult<Vec<Annotatable>, Annotatable> {
         // FIXME: Built-in derives often forget to give spans contexts,
         // so we are doing it here in a centralized way.
@@ -57,21 +59,28 @@ impl MultiItemModifier for BuiltinDerive {
         match item {
             Annotatable::Stmt(stmt) => {
                 if let ast::StmtKind::Item(item) = stmt.into_inner().kind {
-                    (self.0)(ecx, span, meta_item, &Annotatable::Item(item), &mut |a| {
-                        // Cannot use 'ecx.stmt_item' here, because we need to pass 'ecx'
-                        // to the function
-                        items.push(Annotatable::Stmt(P(ast::Stmt {
-                            id: ast::DUMMY_NODE_ID,
-                            kind: ast::StmtKind::Item(a.expect_item()),
-                            span,
-                        })));
-                    });
+                    (self.0)(
+                        ecx,
+                        span,
+                        meta_item,
+                        &Annotatable::Item(item),
+                        &mut |a| {
+                            // Cannot use 'ecx.stmt_item' here, because we need to pass 'ecx'
+                            // to the function
+                            items.push(Annotatable::Stmt(P(ast::Stmt {
+                                id: ast::DUMMY_NODE_ID,
+                                kind: ast::StmtKind::Item(a.expect_item()),
+                                span,
+                            })));
+                        },
+                        is_derive_const,
+                    );
                 } else {
                     unreachable!("should have already errored on non-item statement")
                 }
             }
             _ => {
-                (self.0)(ecx, span, meta_item, &item, &mut |a| items.push(a));
+                (self.0)(ecx, span, meta_item, &item, &mut |a| items.push(a), is_derive_const);
             }
         }
         ExpandResult::Ready(items)
diff --git a/compiler/rustc_builtin_macros/src/lib.rs b/compiler/rustc_builtin_macros/src/lib.rs
index c7ea7de8f4ea..1cbbfb432647 100644
--- a/compiler/rustc_builtin_macros/src/lib.rs
+++ b/compiler/rustc_builtin_macros/src/lib.rs
@@ -25,6 +25,7 @@ use rustc_expand::base::{MacroExpanderFn, ResolverExpand, SyntaxExtensionKind};
 use rustc_expand::proc_macro::BangProcMacro;
 use rustc_span::symbol::sym;
 
+mod alloc_error_handler;
 mod assert;
 mod cfg;
 mod cfg_accessible;
@@ -94,10 +95,12 @@ pub fn register_builtin_macros(resolver: &mut dyn ResolverExpand) {
     }
 
     register_attr! {
+        alloc_error_handler: alloc_error_handler::expand,
         bench: test::expand_bench,
         cfg_accessible: cfg_accessible::Expander,
         cfg_eval: cfg_eval::expand,
-        derive: derive::Expander,
+        derive: derive::Expander(false),
+        derive_const: derive::Expander(true),
         global_allocator: global_allocator::expand,
         test: test::expand_test,
         test_case: test::expand_test_case,
diff --git a/compiler/rustc_builtin_macros/src/source_util.rs b/compiler/rustc_builtin_macros/src/source_util.rs
index d78bbc3c9322..3411bd40c9de 100644
--- a/compiler/rustc_builtin_macros/src/source_util.rs
+++ b/compiler/rustc_builtin_macros/src/source_util.rs
@@ -216,7 +216,10 @@ pub fn expand_include_bytes(
         }
     };
     match cx.source_map().load_binary_file(&file) {
-        Ok(bytes) => base::MacEager::expr(cx.expr_byte_str(sp, bytes)),
+        Ok(bytes) => {
+            let expr = cx.expr(sp, ast::ExprKind::IncludedBytes(bytes.into()));
+            base::MacEager::expr(expr)
+        }
         Err(e) => {
             cx.span_err(sp, &format!("couldn't read {}: {}", file.display(), e));
             DummyResult::any(sp)
diff --git a/compiler/rustc_builtin_macros/src/test.rs b/compiler/rustc_builtin_macros/src/test.rs
index fee5d04cdae8..b62840d4bc82 100644
--- a/compiler/rustc_builtin_macros/src/test.rs
+++ b/compiler/rustc_builtin_macros/src/test.rs
@@ -112,7 +112,7 @@ pub fn expand_test_or_bench(
     };
 
     // Note: non-associated fn items are already handled by `expand_test_or_bench`
-    if !matches!(item.kind, ast::ItemKind::Fn(_)) {
+    let ast::ItemKind::Fn(fn_) = &item.kind else {
         let diag = &cx.sess.parse_sess.span_diagnostic;
         let msg = "the `#[test]` attribute may only be used on a non-associated function";
         let mut err = match item.kind {
@@ -130,7 +130,7 @@ pub fn expand_test_or_bench(
             .emit();
 
         return vec![Annotatable::Item(item)];
-    }
+    };
 
     // has_*_signature will report any errors in the type so compilation
     // will fail. We shouldn't try to expand in this case because the errors
@@ -141,12 +141,14 @@ pub fn expand_test_or_bench(
         return vec![Annotatable::Item(item)];
     }
 
-    let (sp, attr_sp) = (cx.with_def_site_ctxt(item.span), cx.with_def_site_ctxt(attr_sp));
+    let sp = cx.with_def_site_ctxt(item.span);
+    let ret_ty_sp = cx.with_def_site_ctxt(fn_.sig.decl.output.span());
+    let attr_sp = cx.with_def_site_ctxt(attr_sp);
 
     let test_id = Ident::new(sym::test, attr_sp);
 
     // creates test::$name
-    let test_path = |name| cx.path(sp, vec![test_id, Ident::from_str_and_span(name, sp)]);
+    let test_path = |name| cx.path(ret_ty_sp, vec![test_id, Ident::from_str_and_span(name, sp)]);
 
     // creates test::ShouldPanic::$name
     let should_panic_path = |name| {
@@ -192,7 +194,7 @@ pub fn expand_test_or_bench(
                         vec![
                             // super::$test_fn(b)
                             cx.expr_call(
-                                sp,
+                                ret_ty_sp,
                                 cx.expr_path(cx.path(sp, vec![item.ident])),
                                 vec![cx.expr_ident(sp, b)],
                             ),
@@ -216,7 +218,11 @@ pub fn expand_test_or_bench(
                         cx.expr_path(test_path("assert_test_result")),
                         vec![
                             // $test_fn()
-                            cx.expr_call(sp, cx.expr_path(cx.path(sp, vec![item.ident])), vec![]), // )
+                            cx.expr_call(
+                                ret_ty_sp,
+                                cx.expr_path(cx.path(sp, vec![item.ident])),
+                                vec![],
+                            ), // )
                         ],
                     ), // }
                 ), // )
diff --git a/compiler/rustc_codegen_cranelift/src/allocator.rs b/compiler/rustc_codegen_cranelift/src/allocator.rs
index bad8a87b9bee..12bb00d346db 100644
--- a/compiler/rustc_codegen_cranelift/src/allocator.rs
+++ b/compiler/rustc_codegen_cranelift/src/allocator.rs
@@ -5,6 +5,7 @@ use crate::prelude::*;
 
 use rustc_ast::expand::allocator::{AllocatorKind, AllocatorTy, ALLOCATOR_METHODS};
 use rustc_session::config::OomStrategy;
+use rustc_span::symbol::sym;
 
 /// Returns whether an allocator shim was created
 pub(crate) fn codegen(
@@ -23,7 +24,7 @@ pub(crate) fn codegen(
             module,
             unwind_context,
             kind,
-            tcx.lang_items().oom().is_some(),
+            tcx.alloc_error_handler_kind(()).unwrap(),
             tcx.sess.opts.unstable_opts.oom,
         );
         true
@@ -36,7 +37,7 @@ fn codegen_inner(
     module: &mut impl Module,
     unwind_context: &mut UnwindContext,
     kind: AllocatorKind,
-    has_alloc_error_handler: bool,
+    alloc_error_handler_kind: AllocatorKind,
     oom_strategy: OomStrategy,
 ) {
     let usize_ty = module.target_config().pointer_type();
@@ -108,12 +109,12 @@ fn codegen_inner(
         returns: vec![],
     };
 
-    let callee_name = if has_alloc_error_handler { "__rg_oom" } else { "__rdl_oom" };
+    let callee_name = alloc_error_handler_kind.fn_name(sym::oom);
 
     let func_id =
         module.declare_function("__rust_alloc_error_handler", Linkage::Export, &sig).unwrap();
 
-    let callee_func_id = module.declare_function(callee_name, Linkage::Import, &sig).unwrap();
+    let callee_func_id = module.declare_function(&callee_name, Linkage::Import, &sig).unwrap();
 
     let mut ctx = Context::new();
     ctx.func.signature = sig;
diff --git a/compiler/rustc_codegen_cranelift/src/archive.rs b/compiler/rustc_codegen_cranelift/src/archive.rs
index 31d3d0e06156..f2e3bf16e618 100644
--- a/compiler/rustc_codegen_cranelift/src/archive.rs
+++ b/compiler/rustc_codegen_cranelift/src/archive.rs
@@ -38,6 +38,7 @@ impl ArchiveBuilderBuilder for ArArchiveBuilderBuilder {
         _lib_name: &str,
         _dll_imports: &[rustc_session::cstore::DllImport],
         _tmpdir: &Path,
+        _is_direct_dependency: bool,
     ) -> PathBuf {
         bug!("creating dll imports is not supported");
     }
diff --git a/compiler/rustc_codegen_cranelift/src/base.rs b/compiler/rustc_codegen_cranelift/src/base.rs
index a41b561598f6..1db44502742e 100644
--- a/compiler/rustc_codegen_cranelift/src/base.rs
+++ b/compiler/rustc_codegen_cranelift/src/base.rs
@@ -770,11 +770,7 @@ fn codegen_stmt<'tcx>(
                     lval.write_cvalue(fx, CValue::by_val(operand, box_layout));
                 }
                 Rvalue::NullaryOp(null_op, ty) => {
-                    assert!(
-                        lval.layout()
-                            .ty
-                            .is_sized(fx.tcx.at(stmt.source_info.span), ParamEnv::reveal_all())
-                    );
+                    assert!(lval.layout().ty.is_sized(fx.tcx, ParamEnv::reveal_all()));
                     let layout = fx.layout_of(fx.monomorphize(ty));
                     let val = match null_op {
                         NullOp::SizeOf => layout.size.bytes(),
diff --git a/compiler/rustc_codegen_cranelift/src/constant.rs b/compiler/rustc_codegen_cranelift/src/constant.rs
index d4bc3543b2d1..df1150ec0b8c 100644
--- a/compiler/rustc_codegen_cranelift/src/constant.rs
+++ b/compiler/rustc_codegen_cranelift/src/constant.rs
@@ -5,7 +5,6 @@ use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
 use rustc_middle::mir::interpret::{
     read_target_uint, AllocId, ConstAllocation, ConstValue, ErrorHandled, GlobalAlloc, Scalar,
 };
-use rustc_span::DUMMY_SP;
 
 use cranelift_module::*;
 
@@ -129,7 +128,7 @@ pub(crate) fn codegen_const_value<'tcx>(
     ty: Ty<'tcx>,
 ) -> CValue<'tcx> {
     let layout = fx.layout_of(ty);
-    assert!(!layout.is_unsized(), "sized const value");
+    assert!(layout.is_sized(), "unsized const value");
 
     if layout.is_zst() {
         return CValue::by_ref(crate::Pointer::dangling(layout.align.pref), layout);
@@ -291,7 +290,7 @@ fn data_id_for_static(
     let is_mutable = if tcx.is_mutable_static(def_id) {
         true
     } else {
-        !ty.is_freeze(tcx.at(DUMMY_SP), ParamEnv::reveal_all())
+        !ty.is_freeze(tcx, ParamEnv::reveal_all())
     };
     let align = tcx.layout_of(ParamEnv::reveal_all().and(ty)).unwrap().align.pref.bytes();
 
diff --git a/compiler/rustc_codegen_cranelift/src/debuginfo/mod.rs b/compiler/rustc_codegen_cranelift/src/debuginfo/mod.rs
index c55db2017ee6..2ba012a77b0a 100644
--- a/compiler/rustc_codegen_cranelift/src/debuginfo/mod.rs
+++ b/compiler/rustc_codegen_cranelift/src/debuginfo/mod.rs
@@ -59,7 +59,7 @@ impl DebugContext {
 
         let producer = format!(
             "cg_clif (rustc {}, cranelift {})",
-            rustc_interface::util::version_str().unwrap_or("unknown version"),
+            rustc_interface::util::rustc_version_str().unwrap_or("unknown version"),
             cranelift_codegen::VERSION,
         );
         let comp_dir = tcx
diff --git a/compiler/rustc_codegen_cranelift/src/value_and_place.rs b/compiler/rustc_codegen_cranelift/src/value_and_place.rs
index c3dfbd37279f..c5bd574623df 100644
--- a/compiler/rustc_codegen_cranelift/src/value_and_place.rs
+++ b/compiler/rustc_codegen_cranelift/src/value_and_place.rs
@@ -19,7 +19,7 @@ fn codegen_field<'tcx>(
     };
 
     if let Some(extra) = extra {
-        if !field_layout.is_unsized() {
+        if field_layout.is_sized() {
             return simple(fx);
         }
         match field_layout.ty.kind() {
@@ -364,7 +364,7 @@ impl<'tcx> CPlace<'tcx> {
         fx: &mut FunctionCx<'_, '_, 'tcx>,
         layout: TyAndLayout<'tcx>,
     ) -> CPlace<'tcx> {
-        assert!(!layout.is_unsized());
+        assert!(layout.is_sized());
         if layout.size.bytes() == 0 {
             return CPlace {
                 inner: CPlaceInner::Addr(Pointer::dangling(layout.align.pref), None),
@@ -825,7 +825,7 @@ impl<'tcx> CPlace<'tcx> {
         fx: &FunctionCx<'_, '_, 'tcx>,
         variant: VariantIdx,
     ) -> Self {
-        assert!(!self.layout().is_unsized());
+        assert!(self.layout().is_sized());
         let layout = self.layout().for_variant(fx, variant);
         CPlace { inner: self.inner, layout }
     }
diff --git a/compiler/rustc_codegen_gcc/src/allocator.rs b/compiler/rustc_codegen_gcc/src/allocator.rs
index 58efb81e8001..e2c9ffe9c1c3 100644
--- a/compiler/rustc_codegen_gcc/src/allocator.rs
+++ b/compiler/rustc_codegen_gcc/src/allocator.rs
@@ -7,7 +7,7 @@ use rustc_span::symbol::sym;
 
 use crate::GccContext;
 
-pub(crate) unsafe fn codegen(tcx: TyCtxt<'_>, mods: &mut GccContext, _module_name: &str, kind: AllocatorKind, has_alloc_error_handler: bool) {
+pub(crate) unsafe fn codegen(tcx: TyCtxt<'_>, mods: &mut GccContext, _module_name: &str, kind: AllocatorKind, alloc_error_handler_kind: AllocatorKind) {
     let context = &mods.context;
     let usize =
         match tcx.sess.target.pointer_width {
@@ -90,14 +90,7 @@ pub(crate) unsafe fn codegen(tcx: TyCtxt<'_>, mods: &mut GccContext, _module_nam
         .collect();
     let func = context.new_function(None, FunctionType::Exported, void, &args, name, false);
 
-    let kind =
-        if has_alloc_error_handler {
-            AllocatorKind::Global
-        }
-        else {
-            AllocatorKind::Default
-        };
-    let callee = kind.fn_name(sym::oom);
+    let callee = alloc_error_handler_kind.fn_name(sym::oom);
     let args: Vec<_> = types.iter().enumerate()
         .map(|(index, typ)| context.new_parameter(None, *typ, &format!("param{}", index)))
         .collect();
diff --git a/compiler/rustc_codegen_gcc/src/archive.rs b/compiler/rustc_codegen_gcc/src/archive.rs
index ac0342f6b80a..f18ae7ea5e9b 100644
--- a/compiler/rustc_codegen_gcc/src/archive.rs
+++ b/compiler/rustc_codegen_gcc/src/archive.rs
@@ -47,6 +47,7 @@ impl ArchiveBuilderBuilder for ArArchiveBuilderBuilder {
         _lib_name: &str,
         _dll_imports: &[DllImport],
         _tmpdir: &Path,
+        _is_direct_dependency: bool,
     ) -> PathBuf {
         unimplemented!();
     }
diff --git a/compiler/rustc_codegen_gcc/src/lib.rs b/compiler/rustc_codegen_gcc/src/lib.rs
index accd02ab0026..dd0daf2c38b1 100644
--- a/compiler/rustc_codegen_gcc/src/lib.rs
+++ b/compiler/rustc_codegen_gcc/src/lib.rs
@@ -153,11 +153,11 @@ impl CodegenBackend for GccCodegenBackend {
 }
 
 impl ExtraBackendMethods for GccCodegenBackend {
-    fn codegen_allocator<'tcx>(&self, tcx: TyCtxt<'tcx>, module_name: &str, kind: AllocatorKind, has_alloc_error_handler: bool) -> Self::Module {
+    fn codegen_allocator<'tcx>(&self, tcx: TyCtxt<'tcx>, module_name: &str, kind: AllocatorKind, alloc_error_handler_kind: AllocatorKind) -> Self::Module {
         let mut mods = GccContext {
             context: Context::default(),
         };
-        unsafe { allocator::codegen(tcx, &mut mods, module_name, kind, has_alloc_error_handler); }
+        unsafe { allocator::codegen(tcx, &mut mods, module_name, kind, alloc_error_handler_kind); }
         mods
     }
 
diff --git a/compiler/rustc_codegen_gcc/src/type_.rs b/compiler/rustc_codegen_gcc/src/type_.rs
index 68bdb8d4e55f..bdf7318ce48c 100644
--- a/compiler/rustc_codegen_gcc/src/type_.rs
+++ b/compiler/rustc_codegen_gcc/src/type_.rs
@@ -201,6 +201,27 @@ impl<'gcc, 'tcx> BaseTypeMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
     fn val_ty(&self, value: RValue<'gcc>) -> Type<'gcc> {
         value.get_type()
     }
+
+    fn type_array(&self, ty: Type<'gcc>, mut len: u64) -> Type<'gcc> {
+        if let Some(struct_type) = ty.is_struct() {
+            if struct_type.get_field_count() == 0 {
+                // NOTE: since gccjit only supports i32 for the array size and libcore's tests uses a
+                // size of usize::MAX in test_binary_search, we workaround this by setting the size to
+                // zero for ZSTs.
+                // FIXME(antoyo): fix gccjit API.
+                len = 0;
+            }
+        }
+
+        // NOTE: see note above. Some other test uses usize::MAX.
+        if len == u64::MAX {
+            len = 0;
+        }
+
+        let len: i32 = len.try_into().expect("array len");
+
+        self.context.new_array_type(None, ty, len)
+    }
 }
 
 impl<'gcc, 'tcx> CodegenCx<'gcc, 'tcx> {
@@ -227,27 +248,6 @@ impl<'gcc, 'tcx> CodegenCx<'gcc, 'tcx> {
         self.context.new_opaque_struct_type(None, name)
     }
 
-    pub fn type_array(&self, ty: Type<'gcc>, mut len: u64) -> Type<'gcc> {
-        if let Some(struct_type) = ty.is_struct() {
-            if struct_type.get_field_count() == 0 {
-                // NOTE: since gccjit only supports i32 for the array size and libcore's tests uses a
-                // size of usize::MAX in test_binary_search, we workaround this by setting the size to
-                // zero for ZSTs.
-                // FIXME(antoyo): fix gccjit API.
-                len = 0;
-            }
-        }
-
-        // NOTE: see note above. Some other test uses usize::MAX.
-        if len == u64::MAX {
-            len = 0;
-        }
-
-        let len: i32 = len.try_into().expect("array len");
-
-        self.context.new_array_type(None, ty, len)
-    }
-
     pub fn type_bool(&self) -> Type<'gcc> {
         self.context.new_type::<bool>()
     }
@@ -277,7 +277,7 @@ pub fn struct_fields<'gcc, 'tcx>(cx: &CodegenCx<'gcc, 'tcx>, layout: TyAndLayout
         offset = target_offset + field.size;
         prev_effective_align = effective_field_align;
     }
-    if !layout.is_unsized() && field_count > 0 {
+    if layout.is_sized() && field_count > 0 {
         if offset > layout.size {
             bug!("layout: {:#?} stride: {:?} offset: {:?}", layout, layout.size, offset);
         }
diff --git a/compiler/rustc_codegen_llvm/src/allocator.rs b/compiler/rustc_codegen_llvm/src/allocator.rs
index 72961ae888e5..fed56cdd4382 100644
--- a/compiler/rustc_codegen_llvm/src/allocator.rs
+++ b/compiler/rustc_codegen_llvm/src/allocator.rs
@@ -15,7 +15,7 @@ pub(crate) unsafe fn codegen(
     module_llvm: &mut ModuleLlvm,
     module_name: &str,
     kind: AllocatorKind,
-    has_alloc_error_handler: bool,
+    alloc_error_handler_kind: AllocatorKind,
 ) {
     let llcx = &*module_llvm.llcx;
     let llmod = module_llvm.llmod();
@@ -117,8 +117,7 @@ pub(crate) unsafe fn codegen(
         attributes::apply_to_llfn(llfn, llvm::AttributePlace::Function, &[uwtable]);
     }
 
-    let kind = if has_alloc_error_handler { AllocatorKind::Global } else { AllocatorKind::Default };
-    let callee = kind.fn_name(sym::oom);
+    let callee = alloc_error_handler_kind.fn_name(sym::oom);
     let callee = llvm::LLVMRustGetOrInsertFunction(llmod, callee.as_ptr().cast(), callee.len(), ty);
     // -> ! DIFlagNoReturn
     attributes::apply_to_llfn(callee, llvm::AttributePlace::Function, &[no_return]);
diff --git a/compiler/rustc_codegen_llvm/src/asm.rs b/compiler/rustc_codegen_llvm/src/asm.rs
index 017513721b75..219a4f8fa895 100644
--- a/compiler/rustc_codegen_llvm/src/asm.rs
+++ b/compiler/rustc_codegen_llvm/src/asm.rs
@@ -130,7 +130,7 @@ impl<'ll, 'tcx> AsmBuilderMethods<'tcx> for Builder<'_, 'll, 'tcx> {
                     op_idx.insert(idx, constraints.len());
                     constraints.push(reg_to_llvm(reg, Some(&value.layout)));
                 }
-                InlineAsmOperandRef::InOut { reg, late: _, in_value, out_place: _ } => {
+                InlineAsmOperandRef::InOut { reg, late, in_value, out_place: _ } => {
                     let value = llvm_fixup_input(
                         self,
                         in_value.immediate(),
@@ -138,7 +138,16 @@ impl<'ll, 'tcx> AsmBuilderMethods<'tcx> for Builder<'_, 'll, 'tcx> {
                         &in_value.layout,
                     );
                     inputs.push(value);
-                    constraints.push(format!("{}", op_idx[&idx]));
+
+                    // In the case of fixed registers, we have the choice of
+                    // either using a tied operand or duplicating the constraint.
+                    // We prefer the latter because it matches the behavior of
+                    // Clang.
+                    if late && matches!(reg, InlineAsmRegOrRegClass::Reg(_)) {
+                        constraints.push(format!("{}", reg_to_llvm(reg, Some(&in_value.layout))));
+                    } else {
+                        constraints.push(format!("{}", op_idx[&idx]));
+                    }
                 }
                 InlineAsmOperandRef::SymFn { instance } => {
                     inputs.push(self.cx.get_fn(instance));
@@ -276,13 +285,13 @@ impl<'ll, 'tcx> AsmBuilderMethods<'tcx> for Builder<'_, 'll, 'tcx> {
         let mut attrs = SmallVec::<[_; 2]>::new();
         if options.contains(InlineAsmOptions::PURE) {
             if options.contains(InlineAsmOptions::NOMEM) {
-                attrs.push(llvm::AttributeKind::ReadNone.create_attr(self.cx.llcx));
+                attrs.push(llvm::MemoryEffects::None.create_attr(self.cx.llcx));
             } else if options.contains(InlineAsmOptions::READONLY) {
-                attrs.push(llvm::AttributeKind::ReadOnly.create_attr(self.cx.llcx));
+                attrs.push(llvm::MemoryEffects::ReadOnly.create_attr(self.cx.llcx));
             }
             attrs.push(llvm::AttributeKind::WillReturn.create_attr(self.cx.llcx));
         } else if options.contains(InlineAsmOptions::NOMEM) {
-            attrs.push(llvm::AttributeKind::InaccessibleMemOnly.create_attr(self.cx.llcx));
+            attrs.push(llvm::MemoryEffects::InaccessibleMemOnly.create_attr(self.cx.llcx));
         } else {
             // LLVM doesn't have an attribute to represent ReadOnly + SideEffect
         }
@@ -496,6 +505,44 @@ fn xmm_reg_index(reg: InlineAsmReg) -> Option<u32> {
     }
 }
 
+/// If the register is an AArch64 integer register then return its index.
+fn a64_reg_index(reg: InlineAsmReg) -> Option<u32> {
+    match reg {
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x0) => Some(0),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x1) => Some(1),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x2) => Some(2),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x3) => Some(3),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x4) => Some(4),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x5) => Some(5),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x6) => Some(6),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x7) => Some(7),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x8) => Some(8),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x9) => Some(9),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x10) => Some(10),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x11) => Some(11),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x12) => Some(12),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x13) => Some(13),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x14) => Some(14),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x15) => Some(15),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x16) => Some(16),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x17) => Some(17),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x18) => Some(18),
+        // x19 is reserved
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x20) => Some(20),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x21) => Some(21),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x22) => Some(22),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x23) => Some(23),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x24) => Some(24),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x25) => Some(25),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x26) => Some(26),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x27) => Some(27),
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x28) => Some(28),
+        // x29 is reserved
+        InlineAsmReg::AArch64(AArch64InlineAsmReg::x30) => Some(30),
+        _ => None,
+    }
+}
+
 /// If the register is an AArch64 vector register then return its index.
 fn a64_vreg_index(reg: InlineAsmReg) -> Option<u32> {
     match reg {
@@ -526,6 +573,22 @@ fn reg_to_llvm(reg: InlineAsmRegOrRegClass, layout: Option<&TyAndLayout<'_>>) ->
                     'x'
                 };
                 format!("{{{}mm{}}}", class, idx)
+            } else if let Some(idx) = a64_reg_index(reg) {
+                let class = if let Some(layout) = layout {
+                    match layout.size.bytes() {
+                        8 => 'x',
+                        _ => 'w',
+                    }
+                } else {
+                    // We use i32 as the type for discarded outputs
+                    'w'
+                };
+                if class == 'x' && reg == InlineAsmReg::AArch64(AArch64InlineAsmReg::x30) {
+                    // LLVM doesn't recognize x30. use lr instead.
+                    "{lr}".to_string()
+                } else {
+                    format!("{{{}{}}}", class, idx)
+                }
             } else if let Some(idx) = a64_vreg_index(reg) {
                 let class = if let Some(layout) = layout {
                     match layout.size.bytes() {
@@ -541,9 +604,6 @@ fn reg_to_llvm(reg: InlineAsmRegOrRegClass, layout: Option<&TyAndLayout<'_>>) ->
                     'q'
                 };
                 format!("{{{}{}}}", class, idx)
-            } else if reg == InlineAsmReg::AArch64(AArch64InlineAsmReg::x30) {
-                // LLVM doesn't recognize x30
-                "{lr}".to_string()
             } else if reg == InlineAsmReg::Arm(ArmInlineAsmReg::r14) {
                 // LLVM doesn't recognize r14
                 "{lr}".to_string()
diff --git a/compiler/rustc_codegen_llvm/src/attributes.rs b/compiler/rustc_codegen_llvm/src/attributes.rs
index eff2436d41ca..a8b47633519a 100644
--- a/compiler/rustc_codegen_llvm/src/attributes.rs
+++ b/compiler/rustc_codegen_llvm/src/attributes.rs
@@ -12,8 +12,9 @@ use rustc_target::spec::{FramePointer, SanitizerSet, StackProbeType, StackProtec
 use smallvec::SmallVec;
 
 use crate::attributes;
+use crate::errors::{MissingFeatures, SanitizerMemtagRequiresMte, TargetFeatureDisableOrEnable};
 use crate::llvm::AttributePlace::Function;
-use crate::llvm::{self, AllocKindFlags, Attribute, AttributeKind, AttributePlace};
+use crate::llvm::{self, AllocKindFlags, Attribute, AttributeKind, AttributePlace, MemoryEffects};
 use crate::llvm_util;
 pub use rustc_attr::{InlineAttr, InstructionSetAttr, OptimizeAttr};
 
@@ -82,7 +83,7 @@ pub fn sanitize_attrs<'ll>(
         let mte_feature =
             features.iter().map(|s| &s[..]).rfind(|n| ["+mte", "-mte"].contains(&&n[..]));
         if let None | Some("-mte") = mte_feature {
-            cx.tcx.sess.err("`-Zsanitizer=memtag` requires `-Ctarget-feature=+mte`");
+            cx.tcx.sess.emit_err(SanitizerMemtagRequiresMte);
         }
 
         attrs.push(llvm::AttributeKind::SanitizeMemTag.create_attr(cx.llcx));
@@ -303,10 +304,10 @@ pub fn from_fn_attrs<'ll, 'tcx>(
         to_add.push(AttributeKind::ReturnsTwice.create_attr(cx.llcx));
     }
     if codegen_fn_attrs.flags.contains(CodegenFnAttrFlags::FFI_PURE) {
-        to_add.push(AttributeKind::ReadOnly.create_attr(cx.llcx));
+        to_add.push(MemoryEffects::ReadOnly.create_attr(cx.llcx));
     }
     if codegen_fn_attrs.flags.contains(CodegenFnAttrFlags::FFI_CONST) {
-        to_add.push(AttributeKind::ReadNone.create_attr(cx.llcx));
+        to_add.push(MemoryEffects::None.create_attr(cx.llcx));
     }
     if codegen_fn_attrs.flags.contains(CodegenFnAttrFlags::NAKED) {
         to_add.push(AttributeKind::Naked.create_attr(cx.llcx));
@@ -393,13 +394,14 @@ pub fn from_fn_attrs<'ll, 'tcx>(
             .get_attrs(instance.def_id(), sym::target_feature)
             .next()
             .map_or_else(|| cx.tcx.def_span(instance.def_id()), |a| a.span);
-        let msg = format!(
-            "the target features {} must all be either enabled or disabled together",
-            f.join(", ")
-        );
-        let mut err = cx.tcx.sess.struct_span_err(span, &msg);
-        err.help("add the missing features in a `target_feature` attribute");
-        err.emit();
+        cx.tcx
+            .sess
+            .create_err(TargetFeatureDisableOrEnable {
+                features: f,
+                span: Some(span),
+                missing_features: Some(MissingFeatures),
+            })
+            .emit();
         return;
     }
 
diff --git a/compiler/rustc_codegen_llvm/src/back/archive.rs b/compiler/rustc_codegen_llvm/src/back/archive.rs
index 20a063f80fd0..5c68abeb08ba 100644
--- a/compiler/rustc_codegen_llvm/src/back/archive.rs
+++ b/compiler/rustc_codegen_llvm/src/back/archive.rs
@@ -12,6 +12,10 @@ use std::str;
 use object::read::macho::FatArch;
 
 use crate::common;
+use crate::errors::{
+    ArchiveBuildFailure, DlltoolFailImportLibrary, ErrorCallingDllTool, ErrorCreatingImportLibrary,
+    ErrorWritingDEFFile, UnknownArchiveKind,
+};
 use crate::llvm::archive_ro::{ArchiveRO, Child};
 use crate::llvm::{self, ArchiveKind, LLVMMachineType, LLVMRustCOFFShortExport};
 use rustc_codegen_ssa::back::archive::{ArchiveBuilder, ArchiveBuilderBuilder};
@@ -147,7 +151,7 @@ impl<'a> ArchiveBuilder<'a> for LlvmArchiveBuilder<'a> {
     fn build(mut self: Box<Self>, output: &Path) -> bool {
         match self.build_with_llvm(output) {
             Ok(any_members) => any_members,
-            Err(e) => self.sess.fatal(&format!("failed to build archive: {}", e)),
+            Err(e) => self.sess.emit_fatal(ArchiveBuildFailure { error: e }),
         }
     }
 }
@@ -165,10 +169,12 @@ impl ArchiveBuilderBuilder for LlvmArchiveBuilderBuilder {
         lib_name: &str,
         dll_imports: &[DllImport],
         tmpdir: &Path,
+        is_direct_dependency: bool,
     ) -> PathBuf {
+        let name_suffix = if is_direct_dependency { "_imports" } else { "_imports_indirect" };
         let output_path = {
             let mut output_path: PathBuf = tmpdir.to_path_buf();
-            output_path.push(format!("{}_imports", lib_name));
+            output_path.push(format!("{}{}", lib_name, name_suffix));
             output_path.with_extension("lib")
         };
 
@@ -195,7 +201,8 @@ impl ArchiveBuilderBuilder for LlvmArchiveBuilderBuilder {
             // that loaded but crashed with an AV upon calling one of the imported
             // functions.  Therefore, use binutils to create the import library instead,
             // by writing a .DEF file to the temp dir and calling binutils's dlltool.
-            let def_file_path = tmpdir.join(format!("{}_imports", lib_name)).with_extension("def");
+            let def_file_path =
+                tmpdir.join(format!("{}{}", lib_name, name_suffix)).with_extension("def");
 
             let def_file_content = format!(
                 "EXPORTS\n{}",
@@ -214,7 +221,7 @@ impl ArchiveBuilderBuilder for LlvmArchiveBuilderBuilder {
             match std::fs::write(&def_file_path, def_file_content) {
                 Ok(_) => {}
                 Err(e) => {
-                    sess.fatal(&format!("Error writing .DEF file: {}", e));
+                    sess.emit_fatal(ErrorWritingDEFFile { error: e });
                 }
             };
 
@@ -236,13 +243,14 @@ impl ArchiveBuilderBuilder for LlvmArchiveBuilderBuilder {
 
             match result {
                 Err(e) => {
-                    sess.fatal(&format!("Error calling dlltool: {}", e));
+                    sess.emit_fatal(ErrorCallingDllTool { error: e });
+                }
+                Ok(output) if !output.status.success() => {
+                    sess.emit_fatal(DlltoolFailImportLibrary {
+                        stdout: String::from_utf8_lossy(&output.stdout),
+                        stderr: String::from_utf8_lossy(&output.stderr),
+                    })
                 }
-                Ok(output) if !output.status.success() => sess.fatal(&format!(
-                    "Dlltool could not create import library: {}\n{}",
-                    String::from_utf8_lossy(&output.stdout),
-                    String::from_utf8_lossy(&output.stderr)
-                )),
                 _ => {}
             }
         } else {
@@ -290,11 +298,10 @@ impl ArchiveBuilderBuilder for LlvmArchiveBuilderBuilder {
             };
 
             if result == crate::llvm::LLVMRustResult::Failure {
-                sess.fatal(&format!(
-                    "Error creating import library for {}: {}",
+                sess.emit_fatal(ErrorCreatingImportLibrary {
                     lib_name,
-                    llvm::last_error().unwrap_or("unknown LLVM error".to_string())
-                ));
+                    error: llvm::last_error().unwrap_or("unknown LLVM error".to_string()),
+                });
             }
         };
 
@@ -305,9 +312,10 @@ impl ArchiveBuilderBuilder for LlvmArchiveBuilderBuilder {
 impl<'a> LlvmArchiveBuilder<'a> {
     fn build_with_llvm(&mut self, output: &Path) -> io::Result<bool> {
         let kind = &*self.sess.target.archive_format;
-        let kind = kind.parse::<ArchiveKind>().map_err(|_| kind).unwrap_or_else(|kind| {
-            self.sess.fatal(&format!("Don't know how to build archive of type: {}", kind))
-        });
+        let kind = kind
+            .parse::<ArchiveKind>()
+            .map_err(|_| kind)
+            .unwrap_or_else(|kind| self.sess.emit_fatal(UnknownArchiveKind { kind }));
 
         let mut additions = mem::take(&mut self.additions);
         let mut strings = Vec::new();
diff --git a/compiler/rustc_codegen_llvm/src/back/lto.rs b/compiler/rustc_codegen_llvm/src/back/lto.rs
index a49cc7f8d662..3fa21355b7f4 100644
--- a/compiler/rustc_codegen_llvm/src/back/lto.rs
+++ b/compiler/rustc_codegen_llvm/src/back/lto.rs
@@ -1,4 +1,5 @@
 use crate::back::write::{self, save_temp_bitcode, DiagnosticHandlers};
+use crate::errors::DynamicLinkingWithLTO;
 use crate::llvm::{self, build_string};
 use crate::{LlvmCodegenBackend, ModuleLlvm};
 use object::read::archive::ArchiveFile;
@@ -90,13 +91,7 @@ fn prepare_lto(
         }
 
         if cgcx.opts.cg.prefer_dynamic && !cgcx.opts.unstable_opts.dylib_lto {
-            diag_handler
-                .struct_err("cannot prefer dynamic linking when performing LTO")
-                .note(
-                    "only 'staticlib', 'bin', and 'cdylib' outputs are \
-                               supported with LTO",
-                )
-                .emit();
+            diag_handler.emit_err(DynamicLinkingWithLTO);
             return Err(FatalError);
         }
 
diff --git a/compiler/rustc_codegen_llvm/src/back/write.rs b/compiler/rustc_codegen_llvm/src/back/write.rs
index 11053a8f6c45..97d0de47b3a6 100644
--- a/compiler/rustc_codegen_llvm/src/back/write.rs
+++ b/compiler/rustc_codegen_llvm/src/back/write.rs
@@ -765,11 +765,21 @@ pub(crate) unsafe fn codegen(
         drop(handlers);
     }
 
+    // `.dwo` files are only emitted if:
+    //
+    // - Object files are being emitted (i.e. bitcode only or metadata only compilations will not
+    //   produce dwarf objects, even if otherwise enabled)
+    // - Target supports Split DWARF
+    // - Split debuginfo is enabled
+    // - Split DWARF kind is `split` (i.e. debuginfo is split into `.dwo` files, not different
+    //   sections in the `.o` files).
+    let dwarf_object_emitted = matches!(config.emit_obj, EmitObj::ObjectCode(_))
+        && cgcx.target_can_use_split_dwarf
+        && cgcx.split_debuginfo != SplitDebuginfo::Off
+        && cgcx.split_dwarf_kind == SplitDwarfKind::Split;
     Ok(module.into_compiled_module(
         config.emit_obj != EmitObj::None,
-        cgcx.target_can_use_split_dwarf
-            && cgcx.split_debuginfo != SplitDebuginfo::Off
-            && cgcx.split_dwarf_kind == SplitDwarfKind::Split,
+        dwarf_object_emitted,
         config.emit_bc,
         &cgcx.output_filenames,
     ))
diff --git a/compiler/rustc_codegen_llvm/src/builder.rs b/compiler/rustc_codegen_llvm/src/builder.rs
index fca43a0d86dd..9cb36ce7f189 100644
--- a/compiler/rustc_codegen_llvm/src/builder.rs
+++ b/compiler/rustc_codegen_llvm/src/builder.rs
@@ -365,11 +365,14 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
                 Int(I64) => "llvm.ssub.with.overflow.i64",
                 Int(I128) => "llvm.ssub.with.overflow.i128",
 
-                Uint(U8) => "llvm.usub.with.overflow.i8",
-                Uint(U16) => "llvm.usub.with.overflow.i16",
-                Uint(U32) => "llvm.usub.with.overflow.i32",
-                Uint(U64) => "llvm.usub.with.overflow.i64",
-                Uint(U128) => "llvm.usub.with.overflow.i128",
+                Uint(_) => {
+                    // Emit sub and icmp instead of llvm.usub.with.overflow. LLVM considers these
+                    // to be the canonical form. It will attempt to reform llvm.usub.with.overflow
+                    // in the backend if profitable.
+                    let sub = self.sub(lhs, rhs);
+                    let cmp = self.icmp(IntPredicate::IntULT, lhs, rhs);
+                    return (sub, cmp);
+                }
 
                 _ => unreachable!(),
             },
diff --git a/compiler/rustc_codegen_llvm/src/consts.rs b/compiler/rustc_codegen_llvm/src/consts.rs
index dd3c43ba5ca7..3b504d3a7df7 100644
--- a/compiler/rustc_codegen_llvm/src/consts.rs
+++ b/compiler/rustc_codegen_llvm/src/consts.rs
@@ -1,6 +1,7 @@
 use crate::base;
 use crate::common::{self, CodegenCx};
 use crate::debuginfo;
+use crate::errors::{InvalidMinimumAlignment, LinkageConstOrMutType, SymbolAlreadyDefined};
 use crate::llvm::{self, True};
 use crate::llvm_util;
 use crate::type_::Type;
@@ -19,6 +20,7 @@ use rustc_middle::mir::mono::MonoItem;
 use rustc_middle::ty::layout::LayoutOf;
 use rustc_middle::ty::{self, Instance, Ty};
 use rustc_middle::{bug, span_bug};
+use rustc_session::config::Lto;
 use rustc_target::abi::{
     AddressSpace, Align, HasDataLayout, Primitive, Scalar, Size, WrappingRange,
 };
@@ -145,7 +147,7 @@ fn set_global_alignment<'ll>(cx: &CodegenCx<'ll, '_>, gv: &'ll Value, mut align:
         match Align::from_bits(min) {
             Ok(min) => align = align.max(min),
             Err(err) => {
-                cx.sess().err(&format!("invalid minimum global alignment: {}", err));
+                cx.sess().emit_err(InvalidMinimumAlignment { err });
             }
         }
     }
@@ -173,10 +175,7 @@ fn check_and_apply_linkage<'ll, 'tcx>(
         let llty2 = if let ty::RawPtr(ref mt) = ty.kind() {
             cx.layout_of(mt.ty).llvm_type(cx)
         } else {
-            cx.sess().span_fatal(
-                cx.tcx.def_span(def_id),
-                "must have type `*const T` or `*mut T` due to `#[linkage]` attribute",
-            )
+            cx.sess().emit_fatal(LinkageConstOrMutType { span: cx.tcx.def_span(def_id) })
         };
         unsafe {
             // Declare a symbol `foo` with the desired linkage.
@@ -192,10 +191,10 @@ fn check_and_apply_linkage<'ll, 'tcx>(
             let mut real_name = "_rust_extern_with_linkage_".to_string();
             real_name.push_str(sym);
             let g2 = cx.define_global(&real_name, llty).unwrap_or_else(|| {
-                cx.sess().span_fatal(
-                    cx.tcx.def_span(def_id),
-                    &format!("symbol `{}` is already defined", &sym),
-                )
+                cx.sess().emit_fatal(SymbolAlreadyDefined {
+                    span: cx.tcx.def_span(def_id),
+                    symbol_name: sym,
+                })
             });
             llvm::LLVMRustSetLinkage(g2, llvm::Linkage::InternalLinkage);
             llvm::LLVMSetInitializer(g2, g1);
@@ -303,7 +302,8 @@ impl<'ll> CodegenCx<'ll, '_> {
                 // ThinLTO can't handle this workaround in all cases, so we don't
                 // emit the attrs. Instead we make them unnecessary by disallowing
                 // dynamic linking when linker plugin based LTO is enabled.
-                !self.tcx.sess.opts.cg.linker_plugin_lto.enabled();
+                !self.tcx.sess.opts.cg.linker_plugin_lto.enabled() &&
+                self.tcx.sess.lto() != Lto::Thin;
 
             // If this assertion triggers, there's something wrong with commandline
             // argument validation.
diff --git a/compiler/rustc_codegen_llvm/src/context.rs b/compiler/rustc_codegen_llvm/src/context.rs
index 79ddfd884dfa..eaa2ccfc835c 100644
--- a/compiler/rustc_codegen_llvm/src/context.rs
+++ b/compiler/rustc_codegen_llvm/src/context.rs
@@ -3,6 +3,7 @@ use crate::back::write::to_llvm_code_model;
 use crate::callee::get_fn;
 use crate::coverageinfo;
 use crate::debuginfo;
+use crate::errors::BranchProtectionRequiresAArch64;
 use crate::llvm;
 use crate::llvm_util;
 use crate::type_::Type;
@@ -26,6 +27,7 @@ use rustc_session::config::{BranchProtection, CFGuard, CFProtection};
 use rustc_session::config::{CrateType, DebugInfo, PAuthKey, PacRet};
 use rustc_session::Session;
 use rustc_span::source_map::Span;
+use rustc_span::source_map::Spanned;
 use rustc_target::abi::{
     call::FnAbi, HasDataLayout, PointeeInfo, Size, TargetDataLayout, VariantIdx,
 };
@@ -158,6 +160,10 @@ pub unsafe fn create_module<'ll>(
         if sess.target.arch == "s390x" {
             target_data_layout = target_data_layout.replace("-v128:64", "");
         }
+
+        if sess.target.arch == "riscv64" {
+            target_data_layout = target_data_layout.replace("-n32:64-", "-n64-");
+        }
     }
 
     // Ensure the data-layout values hardcoded remain the defaults.
@@ -271,7 +277,7 @@ pub unsafe fn create_module<'ll>(
 
     if let Some(BranchProtection { bti, pac_ret }) = sess.opts.unstable_opts.branch_protection {
         if sess.target.arch != "aarch64" {
-            sess.err("-Zbranch-protection is only supported on aarch64");
+            sess.emit_err(BranchProtectionRequiresAArch64);
         } else {
             llvm::LLVMRustAddModuleFlag(
                 llmod,
@@ -947,7 +953,7 @@ impl<'tcx> LayoutOfHelpers<'tcx> for CodegenCx<'_, 'tcx> {
     #[inline]
     fn handle_layout_err(&self, err: LayoutError<'tcx>, span: Span, ty: Ty<'tcx>) -> ! {
         if let LayoutError::SizeOverflow(_) = err {
-            self.sess().span_fatal(span, &err.to_string())
+            self.sess().emit_fatal(Spanned { span, node: err })
         } else {
             span_bug!(span, "failed to get layout for `{}`: {}", ty, err)
         }
@@ -965,7 +971,7 @@ impl<'tcx> FnAbiOfHelpers<'tcx> for CodegenCx<'_, 'tcx> {
         fn_abi_request: FnAbiRequest<'tcx>,
     ) -> ! {
         if let FnAbiError::Layout(LayoutError::SizeOverflow(_)) = err {
-            self.sess().span_fatal(span, &err.to_string())
+            self.sess().emit_fatal(Spanned { span, node: err })
         } else {
             match fn_abi_request {
                 FnAbiRequest::OfFnPtr { sig, extra_args } => {
diff --git a/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs b/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs
index 433f043209e5..8a8d889a2986 100644
--- a/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs
+++ b/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs
@@ -1,5 +1,6 @@
 use crate::common::CodegenCx;
 use crate::coverageinfo;
+use crate::errors::InstrumentCoverageRequiresLLVM12;
 use crate::llvm;
 
 use llvm::coverageinfo::CounterMappingRegion;
@@ -37,7 +38,7 @@ pub fn finalize<'ll, 'tcx>(cx: &CodegenCx<'ll, 'tcx>) {
     // LLVM 12.
     let version = coverageinfo::mapping_version();
     if version < 4 {
-        tcx.sess.fatal("rustc option `-C instrument-coverage` requires LLVM 12 or higher.");
+        tcx.sess.emit_fatal(InstrumentCoverageRequiresLLVM12);
     }
 
     debug!("Generating coverage map for CodegenUnit: `{}`", cx.codegen_unit.name());
diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/utils.rs b/compiler/rustc_codegen_llvm/src/debuginfo/utils.rs
index a40cfc8b23fb..5cd0e1cb63ae 100644
--- a/compiler/rustc_codegen_llvm/src/debuginfo/utils.rs
+++ b/compiler/rustc_codegen_llvm/src/debuginfo/utils.rs
@@ -72,7 +72,7 @@ pub(crate) fn fat_pointer_kind<'ll, 'tcx>(
         layout.is_unsized()
     );
 
-    if !layout.is_unsized() {
+    if layout.is_sized() {
         return None;
     }
 
diff --git a/compiler/rustc_codegen_llvm/src/errors.rs b/compiler/rustc_codegen_llvm/src/errors.rs
new file mode 100644
index 000000000000..0fafc214f2f5
--- /dev/null
+++ b/compiler/rustc_codegen_llvm/src/errors.rs
@@ -0,0 +1,139 @@
+use std::borrow::Cow;
+
+use rustc_errors::fluent;
+use rustc_errors::DiagnosticBuilder;
+use rustc_errors::ErrorGuaranteed;
+use rustc_errors::Handler;
+use rustc_errors::IntoDiagnostic;
+use rustc_macros::{Diagnostic, Subdiagnostic};
+use rustc_span::Span;
+
+#[derive(Diagnostic)]
+#[diag(codegen_llvm_unknown_ctarget_feature_prefix)]
+#[note]
+pub(crate) struct UnknownCTargetFeaturePrefix<'a> {
+    pub feature: &'a str,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_llvm_unknown_ctarget_feature)]
+#[note]
+pub(crate) struct UnknownCTargetFeature<'a> {
+    pub feature: &'a str,
+    #[subdiagnostic]
+    pub rust_feature: PossibleFeature<'a>,
+}
+
+#[derive(Subdiagnostic)]
+pub(crate) enum PossibleFeature<'a> {
+    #[help(possible_feature)]
+    Some { rust_feature: &'a str },
+    #[help(consider_filing_feature_request)]
+    None,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_llvm_error_creating_import_library)]
+pub(crate) struct ErrorCreatingImportLibrary<'a> {
+    pub lib_name: &'a str,
+    pub error: String,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_llvm_instrument_coverage_requires_llvm_12)]
+pub(crate) struct InstrumentCoverageRequiresLLVM12;
+
+#[derive(Diagnostic)]
+#[diag(codegen_llvm_symbol_already_defined)]
+pub(crate) struct SymbolAlreadyDefined<'a> {
+    #[primary_span]
+    pub span: Span,
+    pub symbol_name: &'a str,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_llvm_branch_protection_requires_aarch64)]
+pub(crate) struct BranchProtectionRequiresAArch64;
+
+#[derive(Diagnostic)]
+#[diag(codegen_llvm_invalid_minimum_alignment)]
+pub(crate) struct InvalidMinimumAlignment {
+    pub err: String,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_llvm_linkage_const_or_mut_type)]
+pub(crate) struct LinkageConstOrMutType {
+    #[primary_span]
+    pub span: Span,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_llvm_sanitizer_memtag_requires_mte)]
+pub(crate) struct SanitizerMemtagRequiresMte;
+
+#[derive(Diagnostic)]
+#[diag(codegen_llvm_archive_build_failure)]
+pub(crate) struct ArchiveBuildFailure {
+    pub error: std::io::Error,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_llvm_error_writing_def_file)]
+pub(crate) struct ErrorWritingDEFFile {
+    pub error: std::io::Error,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_llvm_error_calling_dlltool)]
+pub(crate) struct ErrorCallingDllTool {
+    pub error: std::io::Error,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_llvm_dlltool_fail_import_library)]
+pub(crate) struct DlltoolFailImportLibrary<'a> {
+    pub stdout: Cow<'a, str>,
+    pub stderr: Cow<'a, str>,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_llvm_unknown_archive_kind)]
+pub(crate) struct UnknownArchiveKind<'a> {
+    pub kind: &'a str,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_llvm_dynamic_linking_with_lto)]
+#[note]
+pub(crate) struct DynamicLinkingWithLTO;
+
+#[derive(Diagnostic)]
+#[diag(codegen_llvm_fail_parsing_target_machine_config_to_target_machine)]
+pub(crate) struct FailParsingTargetMachineConfigToTargetMachine {
+    pub error: String,
+}
+
+pub(crate) struct TargetFeatureDisableOrEnable<'a> {
+    pub features: &'a [&'a str],
+    pub span: Option<Span>,
+    pub missing_features: Option<MissingFeatures>,
+}
+
+#[derive(Subdiagnostic)]
+#[help(codegen_llvm_missing_features)]
+pub(crate) struct MissingFeatures;
+
+impl IntoDiagnostic<'_, ErrorGuaranteed> for TargetFeatureDisableOrEnable<'_> {
+    fn into_diagnostic(self, sess: &'_ Handler) -> DiagnosticBuilder<'_, ErrorGuaranteed> {
+        let mut diag = sess.struct_err(fluent::codegen_llvm_target_feature_disable_or_enable);
+        if let Some(span) = self.span {
+            diag.set_span(span);
+        };
+        if let Some(missing_features) = self.missing_features {
+            diag.subdiagnostic(missing_features);
+        }
+        diag.set_arg("features", self.features.join(", "));
+        diag
+    }
+}
diff --git a/compiler/rustc_codegen_llvm/src/intrinsic.rs b/compiler/rustc_codegen_llvm/src/intrinsic.rs
index 825011941a24..cf590a43826e 100644
--- a/compiler/rustc_codegen_llvm/src/intrinsic.rs
+++ b/compiler/rustc_codegen_llvm/src/intrinsic.rs
@@ -340,17 +340,26 @@ impl<'ll, 'tcx> IntrinsicCallMethods<'tcx> for Builder<'_, 'll, 'tcx> {
 
             sym::black_box => {
                 args[0].val.store(self, result);
-
+                let result_val_span = [result.llval];
                 // We need to "use" the argument in some way LLVM can't introspect, and on
                 // targets that support it we can typically leverage inline assembly to do
                 // this. LLVM's interpretation of inline assembly is that it's, well, a black
                 // box. This isn't the greatest implementation since it probably deoptimizes
                 // more than we want, but it's so far good enough.
+                //
+                // For zero-sized types, the location pointed to by the result may be
+                // uninitialized. Do not "use" the result in this case; instead just clobber
+                // the memory.
+                let (constraint, inputs): (&str, &[_]) = if result.layout.is_zst() {
+                    ("~{memory}", &[])
+                } else {
+                    ("r,~{memory}", &result_val_span)
+                };
                 crate::asm::inline_asm_call(
                     self,
                     "",
-                    "r,~{memory}",
-                    &[result.llval],
+                    constraint,
+                    inputs,
                     self.type_void(),
                     true,
                     false,
diff --git a/compiler/rustc_codegen_llvm/src/lib.rs b/compiler/rustc_codegen_llvm/src/lib.rs
index 89c7e51d09ec..246e82545c87 100644
--- a/compiler/rustc_codegen_llvm/src/lib.rs
+++ b/compiler/rustc_codegen_llvm/src/lib.rs
@@ -12,6 +12,8 @@
 #![feature(iter_intersperse)]
 #![recursion_limit = "256"]
 #![allow(rustc::potential_query_instability)]
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 
 #[macro_use]
 extern crate rustc_macros;
@@ -20,6 +22,7 @@ extern crate tracing;
 
 use back::write::{create_informational_target_machine, create_target_machine};
 
+use errors::FailParsingTargetMachineConfigToTargetMachine;
 pub use llvm_util::target_features;
 use rustc_ast::expand::allocator::AllocatorKind;
 use rustc_codegen_ssa::back::lto::{LtoModuleCodegen, SerializedModule, ThinModule};
@@ -62,6 +65,7 @@ mod context;
 mod coverageinfo;
 mod debuginfo;
 mod declare;
+mod errors;
 mod intrinsic;
 
 // The following is a work around that replaces `pub mod llvm;` and that fixes issue 53912.
@@ -108,11 +112,11 @@ impl ExtraBackendMethods for LlvmCodegenBackend {
         tcx: TyCtxt<'tcx>,
         module_name: &str,
         kind: AllocatorKind,
-        has_alloc_error_handler: bool,
+        alloc_error_handler_kind: AllocatorKind,
     ) -> ModuleLlvm {
         let mut module_llvm = ModuleLlvm::new_metadata(tcx, module_name);
         unsafe {
-            allocator::codegen(tcx, &mut module_llvm, module_name, kind, has_alloc_error_handler);
+            allocator::codegen(tcx, &mut module_llvm, module_name, kind, alloc_error_handler_kind);
         }
         module_llvm
     }
@@ -412,7 +416,7 @@ impl ModuleLlvm {
             let tm = match (cgcx.tm_factory)(tm_factory_config) {
                 Ok(m) => m,
                 Err(e) => {
-                    handler.struct_err(&e).emit();
+                    handler.emit_err(FailParsingTargetMachineConfigToTargetMachine { error: e });
                     return Err(FatalError);
                 }
             };
diff --git a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
index 42cb694c0e75..e2d0390821d1 100644
--- a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
+++ b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
@@ -183,7 +183,6 @@ pub enum AttributeKind {
     OptimizeNone = 24,
     ReturnsTwice = 25,
     ReadNone = 26,
-    InaccessibleMemOnly = 27,
     SanitizeHWAddress = 28,
     WillReturn = 29,
     StackProtectReq = 30,
@@ -590,6 +589,15 @@ pub enum ChecksumKind {
     SHA256,
 }
 
+/// LLVMRustMemoryEffects
+#[derive(Copy, Clone)]
+#[repr(C)]
+pub enum MemoryEffects {
+    None,
+    ReadOnly,
+    InaccessibleMemOnly,
+}
+
 extern "C" {
     type Opaque;
 }
@@ -1175,6 +1183,7 @@ extern "C" {
     pub fn LLVMRustCreateUWTableAttr(C: &Context, async_: bool) -> &Attribute;
     pub fn LLVMRustCreateAllocSizeAttr(C: &Context, size_arg: u32) -> &Attribute;
     pub fn LLVMRustCreateAllocKindAttr(C: &Context, size_arg: u64) -> &Attribute;
+    pub fn LLVMRustCreateMemoryEffectsAttr(C: &Context, effects: MemoryEffects) -> &Attribute;
 
     // Operations on functions
     pub fn LLVMRustGetOrInsertFunction<'a>(
diff --git a/compiler/rustc_codegen_llvm/src/llvm/mod.rs b/compiler/rustc_codegen_llvm/src/llvm/mod.rs
index 6602a4ab8636..f820e7523712 100644
--- a/compiler/rustc_codegen_llvm/src/llvm/mod.rs
+++ b/compiler/rustc_codegen_llvm/src/llvm/mod.rs
@@ -185,6 +185,13 @@ impl AttributeKind {
     }
 }
 
+impl MemoryEffects {
+    /// Create an LLVM Attribute with these memory effects.
+    pub fn create_attr(self, llcx: &Context) -> &Attribute {
+        unsafe { LLVMRustCreateMemoryEffectsAttr(llcx, self) }
+    }
+}
+
 pub fn set_section(llglobal: &Value, section_name: &str) {
     let section_name_cstr = CString::new(section_name).expect("unexpected CString error");
     unsafe {
diff --git a/compiler/rustc_codegen_llvm/src/llvm_util.rs b/compiler/rustc_codegen_llvm/src/llvm_util.rs
index 2fd58567c487..e1f54356228d 100644
--- a/compiler/rustc_codegen_llvm/src/llvm_util.rs
+++ b/compiler/rustc_codegen_llvm/src/llvm_util.rs
@@ -1,4 +1,8 @@
 use crate::back::write::create_informational_target_machine;
+use crate::errors::{
+    PossibleFeature, TargetFeatureDisableOrEnable, UnknownCTargetFeature,
+    UnknownCTargetFeaturePrefix,
+};
 use crate::llvm;
 use libc::c_int;
 use rustc_codegen_ssa::target_features::{
@@ -434,12 +438,7 @@ pub(crate) fn global_llvm_features(sess: &Session, diagnostics: bool) -> Vec<Str
                 Some(c @ '+' | c @ '-') => c,
                 Some(_) => {
                     if diagnostics {
-                        let mut diag = sess.struct_warn(&format!(
-                            "unknown feature specified for `-Ctarget-feature`: `{}`",
-                            s
-                        ));
-                        diag.note("features must begin with a `+` to enable or `-` to disable it");
-                        diag.emit();
+                        sess.emit_warning(UnknownCTargetFeaturePrefix { feature: s });
                     }
                     return None;
                 }
@@ -456,17 +455,15 @@ pub(crate) fn global_llvm_features(sess: &Session, diagnostics: bool) -> Vec<Str
                         None
                     }
                 });
-                let mut diag = sess.struct_warn(&format!(
-                    "unknown feature specified for `-Ctarget-feature`: `{}`",
-                    feature
-                ));
-                diag.note("it is still passed through to the codegen backend");
-                if let Some(rust_feature) = rust_feature {
-                    diag.help(&format!("you might have meant: `{}`", rust_feature));
+                let unknown_feature = if let Some(rust_feature) = rust_feature {
+                    UnknownCTargetFeature {
+                        feature,
+                        rust_feature: PossibleFeature::Some { rust_feature },
+                    }
                 } else {
-                    diag.note("consider filing a feature request");
-                }
-                diag.emit();
+                    UnknownCTargetFeature { feature, rust_feature: PossibleFeature::None }
+                };
+                sess.emit_warning(unknown_feature);
             }
 
             if diagnostics {
@@ -492,10 +489,11 @@ pub(crate) fn global_llvm_features(sess: &Session, diagnostics: bool) -> Vec<Str
     features.extend(feats);
 
     if diagnostics && let Some(f) = check_tied_features(sess, &featsmap) {
-        sess.err(&format!(
-            "target features {} must all be enabled or disabled together",
-            f.join(", ")
-        ));
+        sess.emit_err(TargetFeatureDisableOrEnable {
+            features: f,
+            span: None,
+            missing_features: None,
+        });
     }
 
     features
diff --git a/compiler/rustc_codegen_llvm/src/mono_item.rs b/compiler/rustc_codegen_llvm/src/mono_item.rs
index 1eceb7f5c87b..76f692b2016f 100644
--- a/compiler/rustc_codegen_llvm/src/mono_item.rs
+++ b/compiler/rustc_codegen_llvm/src/mono_item.rs
@@ -1,6 +1,7 @@
 use crate::attributes;
 use crate::base;
 use crate::context::CodegenCx;
+use crate::errors::SymbolAlreadyDefined;
 use crate::llvm;
 use crate::type_of::LayoutLlvmExt;
 use rustc_codegen_ssa::traits::*;
@@ -25,10 +26,8 @@ impl<'tcx> PreDefineMethods<'tcx> for CodegenCx<'_, 'tcx> {
         let llty = self.layout_of(ty).llvm_type(self);
 
         let g = self.define_global(symbol_name, llty).unwrap_or_else(|| {
-            self.sess().span_fatal(
-                self.tcx.def_span(def_id),
-                &format!("symbol `{}` is already defined", symbol_name),
-            )
+            self.sess()
+                .emit_fatal(SymbolAlreadyDefined { span: self.tcx.def_span(def_id), symbol_name })
         });
 
         unsafe {
diff --git a/compiler/rustc_codegen_llvm/src/type_.rs b/compiler/rustc_codegen_llvm/src/type_.rs
index eeb38d4ecf59..5eec7dc61302 100644
--- a/compiler/rustc_codegen_llvm/src/type_.rs
+++ b/compiler/rustc_codegen_llvm/src/type_.rs
@@ -127,10 +127,6 @@ impl<'ll> CodegenCx<'ll, '_> {
     pub(crate) fn type_variadic_func(&self, args: &[&'ll Type], ret: &'ll Type) -> &'ll Type {
         unsafe { llvm::LLVMFunctionType(ret, args.as_ptr(), args.len() as c_uint, True) }
     }
-
-    pub(crate) fn type_array(&self, ty: &'ll Type, len: u64) -> &'ll Type {
-        unsafe { llvm::LLVMRustArrayType(ty, len) }
-    }
 }
 
 impl<'ll, 'tcx> BaseTypeMethods<'tcx> for CodegenCx<'ll, 'tcx> {
@@ -231,6 +227,10 @@ impl<'ll, 'tcx> BaseTypeMethods<'tcx> for CodegenCx<'ll, 'tcx> {
     fn val_ty(&self, v: &'ll Value) -> &'ll Type {
         common::val_ty(v)
     }
+
+    fn type_array(&self, ty: &'ll Type, len: u64) -> &'ll Type {
+        unsafe { llvm::LLVMRustArrayType(ty, len) }
+    }
 }
 
 impl Type {
diff --git a/compiler/rustc_codegen_llvm/src/type_of.rs b/compiler/rustc_codegen_llvm/src/type_of.rs
index dc1165835e7c..182adf817857 100644
--- a/compiler/rustc_codegen_llvm/src/type_of.rs
+++ b/compiler/rustc_codegen_llvm/src/type_of.rs
@@ -140,7 +140,7 @@ fn struct_llfields<'a, 'tcx>(
         prev_effective_align = effective_field_align;
     }
     let padding_used = result.len() > field_count;
-    if !layout.is_unsized() && field_count > 0 {
+    if layout.is_sized() && field_count > 0 {
         if offset > layout.size {
             bug!("layout: {:#?} stride: {:?} offset: {:?}", layout, layout.size, offset);
         }
diff --git a/compiler/rustc_codegen_ssa/src/back/archive.rs b/compiler/rustc_codegen_ssa/src/back/archive.rs
index bad58d0a8a0a..2b1b06d1644c 100644
--- a/compiler/rustc_codegen_ssa/src/back/archive.rs
+++ b/compiler/rustc_codegen_ssa/src/back/archive.rs
@@ -4,13 +4,17 @@ use rustc_session::cstore::DllImport;
 use rustc_session::Session;
 use rustc_span::symbol::Symbol;
 
+use super::metadata::search_for_section;
+
 use object::read::archive::ArchiveFile;
 
-use std::fmt::Display;
+use std::error::Error;
 use std::fs::File;
 use std::io;
 use std::path::{Path, PathBuf};
 
+use crate::errors::ExtractBundledLibsError;
+
 pub trait ArchiveBuilderBuilder {
     fn new_archive_builder<'a>(&self, sess: &'a Session) -> Box<dyn ArchiveBuilder<'a> + 'a>;
 
@@ -25,34 +29,41 @@ pub trait ArchiveBuilderBuilder {
         lib_name: &str,
         dll_imports: &[DllImport],
         tmpdir: &Path,
+        is_direct_dependency: bool,
     ) -> PathBuf;
 
-    fn extract_bundled_libs(
-        &self,
-        rlib: &Path,
+    fn extract_bundled_libs<'a>(
+        &'a self,
+        rlib: &'a Path,
         outdir: &Path,
         bundled_lib_file_names: &FxHashSet<Symbol>,
-    ) -> Result<(), String> {
-        let message = |msg: &str, e: &dyn Display| format!("{} '{}': {}", msg, &rlib.display(), e);
+    ) -> Result<(), ExtractBundledLibsError<'_>> {
         let archive_map = unsafe {
-            Mmap::map(File::open(rlib).map_err(|e| message("failed to open file", &e))?)
-                .map_err(|e| message("failed to mmap file", &e))?
+            Mmap::map(
+                File::open(rlib)
+                    .map_err(|e| ExtractBundledLibsError::OpenFile { rlib, error: Box::new(e) })?,
+            )
+            .map_err(|e| ExtractBundledLibsError::MmapFile { rlib, error: Box::new(e) })?
         };
         let archive = ArchiveFile::parse(&*archive_map)
-            .map_err(|e| message("failed to parse archive", &e))?;
+            .map_err(|e| ExtractBundledLibsError::ParseArchive { rlib, error: Box::new(e) })?;
 
         for entry in archive.members() {
-            let entry = entry.map_err(|e| message("failed to read entry", &e))?;
+            let entry = entry
+                .map_err(|e| ExtractBundledLibsError::ReadEntry { rlib, error: Box::new(e) })?;
             let data = entry
                 .data(&*archive_map)
-                .map_err(|e| message("failed to get data from archive member", &e))?;
+                .map_err(|e| ExtractBundledLibsError::ArchiveMember { rlib, error: Box::new(e) })?;
             let name = std::str::from_utf8(entry.name())
-                .map_err(|e| message("failed to convert name", &e))?;
+                .map_err(|e| ExtractBundledLibsError::ConvertName { rlib, error: Box::new(e) })?;
             if !bundled_lib_file_names.contains(&Symbol::intern(name)) {
                 continue; // We need to extract only native libraries.
             }
+            let data = search_for_section(rlib, data, ".bundled_lib").map_err(|e| {
+                ExtractBundledLibsError::ExtractSection { rlib, error: Box::<dyn Error>::from(e) }
+            })?;
             std::fs::write(&outdir.join(&name), data)
-                .map_err(|e| message("failed to write file", &e))?;
+                .map_err(|e| ExtractBundledLibsError::WriteFile { rlib, error: Box::new(e) })?;
         }
         Ok(())
     }
diff --git a/compiler/rustc_codegen_ssa/src/back/link.rs b/compiler/rustc_codegen_ssa/src/back/link.rs
index a0b5e3b6daf4..4445e5f6c3a6 100644
--- a/compiler/rustc_codegen_ssa/src/back/link.rs
+++ b/compiler/rustc_codegen_ssa/src/back/link.rs
@@ -6,9 +6,9 @@ use rustc_data_structures::memmap::Mmap;
 use rustc_data_structures::temp_dir::MaybeTempDir;
 use rustc_errors::{ErrorGuaranteed, Handler};
 use rustc_fs_util::fix_windows_verbatim_for_gcc;
-use rustc_hir::def_id::CrateNum;
+use rustc_hir::def_id::{CrateNum, LOCAL_CRATE};
 use rustc_metadata::find_native_static_library;
-use rustc_metadata::fs::{emit_metadata, METADATA_FILENAME};
+use rustc_metadata::fs::{emit_wrapper_file, METADATA_FILENAME};
 use rustc_middle::middle::dependency_format::Linkage;
 use rustc_middle::middle::exported_symbols::SymbolExportKind;
 use rustc_session::config::{self, CFGuard, CrateType, DebugInfo, LdImpl, Lto, Strip};
@@ -24,12 +24,12 @@ use rustc_span::symbol::Symbol;
 use rustc_span::DebuggerVisualizerFile;
 use rustc_target::spec::crt_objects::{CrtObjects, LinkSelfContainedDefault};
 use rustc_target::spec::{Cc, LinkOutputKind, LinkerFlavor, LinkerFlavorCli, Lld, PanicStrategy};
-use rustc_target::spec::{RelocModel, RelroLevel, SanitizerSet, SplitDebuginfo, Target};
+use rustc_target::spec::{RelocModel, RelroLevel, SanitizerSet, SplitDebuginfo};
 
 use super::archive::{ArchiveBuilder, ArchiveBuilderBuilder};
 use super::command::Command;
 use super::linker::{self, Linker};
-use super::metadata::{create_rmeta_file, MetadataPosition};
+use super::metadata::{create_wrapper_file, MetadataPosition};
 use super::rpath::{self, RPathConfig};
 use crate::{
     errors, looks_like_rust_object_file, CodegenResults, CompiledModule, CrateInfo, NativeLib,
@@ -44,7 +44,7 @@ use std::borrow::Borrow;
 use std::cell::OnceCell;
 use std::collections::BTreeSet;
 use std::ffi::OsString;
-use std::fs::{File, OpenOptions};
+use std::fs::{read, File, OpenOptions};
 use std::io::{BufWriter, Write};
 use std::ops::Deref;
 use std::path::{Path, PathBuf};
@@ -292,8 +292,8 @@ fn link_rlib<'a>(
     let trailing_metadata = match flavor {
         RlibFlavor::Normal => {
             let (metadata, metadata_position) =
-                create_rmeta_file(sess, codegen_results.metadata.raw_data());
-            let metadata = emit_metadata(sess, &metadata, tmpdir);
+                create_wrapper_file(sess, b".rmeta".to_vec(), codegen_results.metadata.raw_data());
+            let metadata = emit_wrapper_file(sess, &metadata, tmpdir, METADATA_FILENAME);
             match metadata_position {
                 MetadataPosition::First => {
                     // Most of the time metadata in rlib files is wrapped in a "dummy" object
@@ -376,12 +376,18 @@ fn link_rlib<'a>(
             let location =
                 find_native_static_library(name.as_str(), lib.verbatim, &lib_search_paths, sess);
             if sess.opts.unstable_opts.packed_bundled_libs && flavor == RlibFlavor::Normal {
-                packed_bundled_libs.push(find_native_static_library(
-                    lib.filename.unwrap().as_str(),
+                let filename = lib.filename.unwrap();
+                let lib_path = find_native_static_library(
+                    filename.as_str(),
                     Some(true),
                     &lib_search_paths,
                     sess,
-                ));
+                );
+                let src = read(lib_path)
+                    .map_err(|e| sess.emit_fatal(errors::ReadFileError { message: e }))?;
+                let (data, _) = create_wrapper_file(sess, b".bundled_lib".to_vec(), &src);
+                let wrapper_file = emit_wrapper_file(sess, &data, tmpdir, filename.as_str());
+                packed_bundled_libs.push(wrapper_file);
                 continue;
             }
             ab.add_archive(&location, Box::new(|_| false)).unwrap_or_else(|error| {
@@ -391,13 +397,14 @@ fn link_rlib<'a>(
     }
 
     for (raw_dylib_name, raw_dylib_imports) in
-        collate_raw_dylibs(sess, &codegen_results.crate_info.used_libraries)?
+        collate_raw_dylibs(sess, codegen_results.crate_info.used_libraries.iter())?
     {
         let output_path = archive_builder_builder.create_dll_import_lib(
             sess,
             &raw_dylib_name,
             &raw_dylib_imports,
             tmpdir.as_ref(),
+            true,
         );
 
         ab.add_archive(&output_path, Box::new(|_| false)).unwrap_or_else(|error| {
@@ -449,9 +456,9 @@ fn link_rlib<'a>(
 /// then the CodegenResults value contains one NativeLib instance for each block.  However, the
 /// linker appears to expect only a single import library for each library used, so we need to
 /// collate the symbols together by library name before generating the import libraries.
-fn collate_raw_dylibs(
-    sess: &Session,
-    used_libraries: &[NativeLib],
+fn collate_raw_dylibs<'a, 'b>(
+    sess: &'a Session,
+    used_libraries: impl IntoIterator<Item = &'b NativeLib>,
 ) -> Result<Vec<(String, Vec<DllImport>)>, ErrorGuaranteed> {
     // Use index maps to preserve original order of imports and libraries.
     let mut dylib_table = FxIndexMap::<String, FxIndexMap<Symbol, &DllImport>>::default();
@@ -918,29 +925,17 @@ fn link_natively<'a>(
                         )
                         .is_some();
 
-                        sess.note_without_error("`link.exe` returned an unexpected error");
+                        sess.emit_note(errors::LinkExeUnexpectedError);
                         if is_vs_installed && has_linker {
                             // the linker is broken
-                            sess.note_without_error(
-                                "the Visual Studio build tools may need to be repaired \
-                                using the Visual Studio installer",
-                            );
-                            sess.note_without_error(
-                                "or a necessary component may be missing from the \
-                                \"C++ build tools\" workload",
-                            );
+                            sess.emit_note(errors::RepairVSBuildTools);
+                            sess.emit_note(errors::MissingCppBuildToolComponent);
                         } else if is_vs_installed {
                             // the linker is not installed
-                            sess.note_without_error(
-                                "in the Visual Studio installer, ensure the \
-                                \"C++ build tools\" workload is selected",
-                            );
+                            sess.emit_note(errors::SelectCppBuildToolWorkload);
                         } else {
                             // visual studio is not installed
-                            sess.note_without_error(
-                                "you may need to install Visual Studio build tools with the \
-                                \"C++ build tools\" workload",
-                            );
+                            sess.emit_note(errors::VisualStudioNotInstalled);
                         }
                     }
                 }
@@ -953,35 +948,20 @@ fn link_natively<'a>(
         Err(e) => {
             let linker_not_found = e.kind() == io::ErrorKind::NotFound;
 
-            let mut linker_error = {
-                if linker_not_found {
-                    sess.struct_err(&format!("linker `{}` not found", linker_path.display()))
-                } else {
-                    sess.struct_err(&format!(
-                        "could not exec the linker `{}`",
-                        linker_path.display()
-                    ))
-                }
-            };
-
-            linker_error.note(&e.to_string());
-
-            if !linker_not_found {
-                linker_error.note(&format!("{:?}", &cmd));
+            if linker_not_found {
+                sess.emit_err(errors::LinkerNotFound { linker_path, error: e });
+            } else {
+                sess.emit_err(errors::UnableToExeLinker {
+                    linker_path,
+                    error: e,
+                    command_formatted: format!("{:?}", &cmd),
+                });
             }
 
-            linker_error.emit();
-
             if sess.target.is_like_msvc && linker_not_found {
-                sess.note_without_error(
-                    "the msvc targets depend on the msvc linker \
-                     but `link.exe` was not found",
-                );
-                sess.note_without_error(
-                    "please ensure that Visual Studio 2017 or later, or Build Tools \
-                     for Visual Studio were installed with the Visual C++ option.",
-                );
-                sess.note_without_error("VS Code is a different product, and is not sufficient.");
+                sess.emit_note(errors::MsvcMissingLinker);
+                sess.emit_note(errors::CheckInstalledVisualStudio);
+                sess.emit_note(errors::UnsufficientVSCodeProduct);
             }
             sess.abort_if_errors();
         }
@@ -1006,15 +986,13 @@ fn link_natively<'a>(
                     if !prog.status.success() {
                         let mut output = prog.stderr.clone();
                         output.extend_from_slice(&prog.stdout);
-                        sess.struct_warn(&format!(
-                            "processing debug info with `dsymutil` failed: {}",
-                            prog.status
-                        ))
-                        .note(&escape_string(&output))
-                        .emit();
+                        sess.emit_warning(errors::ProcessingDymutilFailed {
+                            status: prog.status,
+                            output: escape_string(&output),
+                        });
                     }
                 }
-                Err(e) => sess.fatal(&format!("unable to run `dsymutil`: {}", e)),
+                Err(error) => sess.emit_fatal(errors::UnableToRunDsymutil { error }),
             }
         }
 
@@ -1091,15 +1069,14 @@ fn strip_symbols_with_external_utility<'a>(
             if !prog.status.success() {
                 let mut output = prog.stderr.clone();
                 output.extend_from_slice(&prog.stdout);
-                sess.struct_warn(&format!(
-                    "stripping debug info with `{}` failed: {}",
-                    util, prog.status
-                ))
-                .note(&escape_string(&output))
-                .emit();
+                sess.emit_warning(errors::StrippingDebugInfoFailed {
+                    util,
+                    status: prog.status,
+                    output: escape_string(&output),
+                });
             }
         }
-        Err(e) => sess.fatal(&format!("unable to run `{}`: {}", util, e)),
+        Err(error) => sess.emit_fatal(errors::UnableToRun { util, error }),
     }
 }
 
@@ -1152,7 +1129,8 @@ fn link_sanitizer_runtime(sess: &Session, linker: &mut dyn Linker, name: &str) {
         if path.exists() {
             return session_tlib;
         } else {
-            let default_sysroot = filesearch::get_or_default_sysroot();
+            let default_sysroot =
+                filesearch::get_or_default_sysroot().expect("Failed finding sysroot");
             let default_tlib = filesearch::make_target_lib_path(
                 &default_sysroot,
                 sess.opts.target_triple.triple(),
@@ -1250,7 +1228,7 @@ pub fn linker_and_flavor(sess: &Session) -> (PathBuf, LinkerFlavor) {
             )),
             (Some(linker), None) => {
                 let stem = linker.file_stem().and_then(|stem| stem.to_str()).unwrap_or_else(|| {
-                    sess.fatal("couldn't extract file stem from specified linker")
+                    sess.emit_fatal(errors::LinkerFileStem);
                 });
 
                 let flavor = if stem == "emcc" {
@@ -1377,13 +1355,9 @@ fn print_native_static_libs(sess: &Session, all_native_libs: &[NativeLib]) {
         })
         .collect();
     if !lib_args.is_empty() {
-        sess.note_without_error(
-            "Link against the following native artifacts when linking \
-                                 against this static library. The order and any duplication \
-                                 can be significant on some platforms.",
-        );
+        sess.emit_note(errors::StaticLibraryNativeArtifacts);
         // Prefix for greppability
-        sess.note_without_error(&format!("native-static-libs: {}", &lib_args.join(" ")));
+        sess.emit_note(errors::NativeStaticLibs { arguments: lib_args.join(" ") });
     }
 }
 
@@ -1687,14 +1661,14 @@ fn add_link_script(cmd: &mut dyn Linker, sess: &Session, tmpdir: &Path, crate_ty
     match (crate_type, &sess.target.link_script) {
         (CrateType::Cdylib | CrateType::Executable, Some(script)) => {
             if !sess.target.linker_flavor.is_gnu() {
-                sess.fatal("can only use link script when linking with GNU-like linker");
+                sess.emit_fatal(errors::LinkScriptUnavailable);
             }
 
             let file_name = ["rustc", &sess.target.llvm_target, "linkfile.ld"].join("-");
 
             let path = tmpdir.join(file_name);
-            if let Err(e) = fs::write(&path, script.as_ref()) {
-                sess.fatal(&format!("failed to write link script to {}: {}", path.display(), e));
+            if let Err(error) = fs::write(&path, script.as_ref()) {
+                sess.emit_fatal(errors::LinkScriptWriteFailure { path, error });
             }
 
             cmd.arg("--script");
@@ -1840,8 +1814,8 @@ fn add_linked_symbol_object(
 
     let path = tmpdir.join("symbols.o");
     let result = std::fs::write(&path, file.write().unwrap());
-    if let Err(e) = result {
-        sess.fatal(&format!("failed to write {}: {}", path.display(), e));
+    if let Err(error) = result {
+        sess.emit_fatal(errors::FailedToWrite { path, error });
     }
     cmd.add_object(&path);
 }
@@ -2039,15 +2013,9 @@ fn linker_with_args<'a>(
     cmd.add_as_needed();
 
     // Local native libraries of all kinds.
-    //
-    // If `-Zlink-native-libraries=false` is set, then the assumption is that an
-    // external build system already has the native dependencies defined, and it
-    // will provide them to the linker itself.
-    if sess.opts.unstable_opts.link_native_libraries {
-        add_local_native_libraries(cmd, sess, codegen_results);
-    }
+    add_local_native_libraries(cmd, sess, archive_builder_builder, codegen_results, tmpdir);
 
-    // Upstream rust libraries and their (possibly bundled) static native libraries.
+    // Upstream rust crates and their non-dynamic native libraries.
     add_upstream_rust_crates(
         cmd,
         sess,
@@ -2058,23 +2026,47 @@ fn linker_with_args<'a>(
     );
 
     // Dynamic native libraries from upstream crates.
-    //
-    // FIXME: Merge this to `add_upstream_rust_crates` so that all native libraries are linked
-    // together with their respective upstream crates, and in their originally specified order.
-    // This may be slightly breaking due to our use of `--as-needed` and needs a crater run.
-    if sess.opts.unstable_opts.link_native_libraries {
-        add_upstream_native_libraries(cmd, sess, codegen_results);
-    }
+    add_upstream_native_libraries(cmd, sess, archive_builder_builder, codegen_results, tmpdir);
 
     // Link with the import library generated for any raw-dylib functions.
     for (raw_dylib_name, raw_dylib_imports) in
-        collate_raw_dylibs(sess, &codegen_results.crate_info.used_libraries)?
+        collate_raw_dylibs(sess, codegen_results.crate_info.used_libraries.iter())?
     {
         cmd.add_object(&archive_builder_builder.create_dll_import_lib(
             sess,
             &raw_dylib_name,
             &raw_dylib_imports,
             tmpdir,
+            true,
+        ));
+    }
+    // As with add_upstream_native_libraries, we need to add the upstream raw-dylib symbols in case
+    // they are used within inlined functions or instantiated generic functions. We do this *after*
+    // handling the raw-dylib symbols in the current crate to make sure that those are chosen first
+    // by the linker.
+    let (_, dependency_linkage) = codegen_results
+        .crate_info
+        .dependency_formats
+        .iter()
+        .find(|(ty, _)| *ty == crate_type)
+        .expect("failed to find crate type in dependency format list");
+    let native_libraries_from_nonstatics = codegen_results
+        .crate_info
+        .native_libraries
+        .iter()
+        .filter_map(|(cnum, libraries)| {
+            (dependency_linkage[cnum.as_usize() - 1] != Linkage::Static).then(|| libraries)
+        })
+        .flatten();
+    for (raw_dylib_name, raw_dylib_imports) in
+        collate_raw_dylibs(sess, native_libraries_from_nonstatics)?
+    {
+        cmd.add_object(&archive_builder_builder.create_dll_import_lib(
+            sess,
+            &raw_dylib_name,
+            &raw_dylib_imports,
+            tmpdir,
+            false,
         ));
     }
 
@@ -2268,56 +2260,56 @@ fn collect_natvis_visualizers(
                 visualizer_paths.push(visualizer_out_file);
             }
             Err(error) => {
-                sess.warn(
-                    format!(
-                        "Unable to write debugger visualizer file `{}`: {} ",
-                        visualizer_out_file.display(),
-                        error
-                    )
-                    .as_str(),
-                );
+                sess.emit_warning(errors::UnableToWriteDebuggerVisualizer {
+                    path: visualizer_out_file,
+                    error,
+                });
             }
         };
     }
     visualizer_paths
 }
 
-/// # Native library linking
-///
-/// User-supplied library search paths (-L on the command line). These are the same paths used to
-/// find Rust crates, so some of them may have been added already by the previous crate linking
-/// code. This only allows them to be found at compile time so it is still entirely up to outside
-/// forces to make sure that library can be found at runtime.
-///
-/// Also note that the native libraries linked here are only the ones located in the current crate.
-/// Upstream crates with native library dependencies may have their native library pulled in above.
-fn add_local_native_libraries(
+fn add_native_libs_from_crate(
     cmd: &mut dyn Linker,
     sess: &Session,
+    archive_builder_builder: &dyn ArchiveBuilderBuilder,
     codegen_results: &CodegenResults,
+    tmpdir: &Path,
+    search_paths: &OnceCell<Vec<PathBuf>>,
+    bundled_libs: &FxHashSet<Symbol>,
+    cnum: CrateNum,
+    link_static: bool,
+    link_dynamic: bool,
 ) {
-    let filesearch = sess.target_filesearch(PathKind::All);
-    for search_path in filesearch.search_paths() {
-        match search_path.kind {
-            PathKind::Framework => {
-                cmd.framework_path(&search_path.dir);
-            }
-            _ => {
-                cmd.include_path(&fix_windows_verbatim_for_gcc(&search_path.dir));
-            }
-        }
+    if !sess.opts.unstable_opts.link_native_libraries {
+        // If `-Zlink-native-libraries=false` is set, then the assumption is that an
+        // external build system already has the native dependencies defined, and it
+        // will provide them to the linker itself.
+        return;
     }
 
-    let relevant_libs =
-        codegen_results.crate_info.used_libraries.iter().filter(|l| relevant_lib(sess, l));
+    if link_static && cnum != LOCAL_CRATE && !bundled_libs.is_empty() {
+        // If rlib contains native libs as archives, unpack them to tmpdir.
+        let rlib = &codegen_results.crate_info.used_crate_source[&cnum].rlib.as_ref().unwrap().0;
+        archive_builder_builder
+            .extract_bundled_libs(rlib, tmpdir, &bundled_libs)
+            .unwrap_or_else(|e| sess.emit_fatal(e));
+    }
+
+    let native_libs = match cnum {
+        LOCAL_CRATE => &codegen_results.crate_info.used_libraries,
+        _ => &codegen_results.crate_info.native_libraries[&cnum],
+    };
 
-    let search_path = OnceCell::new();
     let mut last = (None, NativeLibKind::Unspecified, None);
-    for lib in relevant_libs {
+    for lib in native_libs {
         let Some(name) = lib.name else {
             continue;
         };
-        let name = name.as_str();
+        if !relevant_lib(sess, lib) {
+            continue;
+        }
 
         // Skip if this library is the same as the last.
         last = if (lib.name, lib.kind, lib.verbatim) == last {
@@ -2326,46 +2318,119 @@ fn add_local_native_libraries(
             (lib.name, lib.kind, lib.verbatim)
         };
 
+        let name = name.as_str();
         let verbatim = lib.verbatim.unwrap_or(false);
         match lib.kind {
+            NativeLibKind::Static { bundle, whole_archive } => {
+                if link_static {
+                    let bundle = bundle.unwrap_or(true);
+                    let whole_archive = whole_archive == Some(true)
+                        // Backward compatibility case: this can be a rlib (so `+whole-archive`
+                        // cannot be added explicitly if necessary, see the error in `fn link_rlib`)
+                        // compiled as an executable due to `--test`. Use whole-archive implicitly,
+                        // like before the introduction of native lib modifiers.
+                        || (whole_archive == None
+                            && bundle
+                            && cnum == LOCAL_CRATE
+                            && sess.opts.test);
+
+                    if bundle && cnum != LOCAL_CRATE {
+                        if let Some(filename) = lib.filename {
+                            // If rlib contains native libs as archives, they are unpacked to tmpdir.
+                            let path = tmpdir.join(filename.as_str());
+                            if whole_archive {
+                                cmd.link_whole_rlib(&path);
+                            } else {
+                                cmd.link_rlib(&path);
+                            }
+                        }
+                    } else {
+                        if whole_archive {
+                            cmd.link_whole_staticlib(
+                                name,
+                                verbatim,
+                                &search_paths.get_or_init(|| archive_search_paths(sess)),
+                            );
+                        } else {
+                            // HACK/FIXME: Fixup a circular dependency between libgcc and libc
+                            // with glibc. This logic should be moved to the libc crate.
+                            if cnum != LOCAL_CRATE
+                                && sess.target.os == "linux"
+                                && sess.target.env == "gnu"
+                                && name == "c"
+                            {
+                                cmd.link_staticlib("gcc", false);
+                            }
+                            cmd.link_staticlib(name, verbatim)
+                        }
+                    }
+                }
+            }
             NativeLibKind::Dylib { as_needed } => {
-                cmd.link_dylib(name, verbatim, as_needed.unwrap_or(true))
+                if link_dynamic {
+                    cmd.link_dylib(name, verbatim, as_needed.unwrap_or(true))
+                }
+            }
+            NativeLibKind::Unspecified => {
+                if link_dynamic {
+                    cmd.link_dylib(name, verbatim, true);
+                }
             }
-            NativeLibKind::Unspecified => cmd.link_dylib(name, verbatim, true),
             NativeLibKind::Framework { as_needed } => {
-                cmd.link_framework(name, as_needed.unwrap_or(true))
-            }
-            NativeLibKind::Static { whole_archive, bundle, .. } => {
-                if whole_archive == Some(true)
-                    // Backward compatibility case: this can be a rlib (so `+whole-archive` cannot
-                    // be added explicitly if necessary, see the error in `fn link_rlib`) compiled
-                    // as an executable due to `--test`. Use whole-archive implicitly, like before
-                    // the introduction of native lib modifiers.
-                    || (whole_archive == None && bundle != Some(false) && sess.opts.test)
-                {
-                    cmd.link_whole_staticlib(
-                        name,
-                        verbatim,
-                        &search_path.get_or_init(|| archive_search_paths(sess)),
-                    );
-                } else {
-                    cmd.link_staticlib(name, verbatim)
+                if link_dynamic {
+                    cmd.link_framework(name, as_needed.unwrap_or(true))
                 }
             }
             NativeLibKind::RawDylib => {
-                // Ignore RawDylib here, they are handled separately in linker_with_args().
+                // Handled separately in `linker_with_args`.
             }
             NativeLibKind::LinkArg => {
-                cmd.arg(name);
+                if link_static {
+                    cmd.arg(name);
+                }
             }
         }
     }
 }
 
-/// # Linking Rust crates and their non-bundled static libraries
-///
-/// Rust crates are not considered at all when creating an rlib output. All dependencies will be
-/// linked when producing the final output (instead of the intermediate rlib version).
+fn add_local_native_libraries(
+    cmd: &mut dyn Linker,
+    sess: &Session,
+    archive_builder_builder: &dyn ArchiveBuilderBuilder,
+    codegen_results: &CodegenResults,
+    tmpdir: &Path,
+) {
+    if sess.opts.unstable_opts.link_native_libraries {
+        // User-supplied library search paths (-L on the command line). These are the same paths
+        // used to find Rust crates, so some of them may have been added already by the previous
+        // crate linking code. This only allows them to be found at compile time so it is still
+        // entirely up to outside forces to make sure that library can be found at runtime.
+        for search_path in sess.target_filesearch(PathKind::All).search_paths() {
+            match search_path.kind {
+                PathKind::Framework => cmd.framework_path(&search_path.dir),
+                _ => cmd.include_path(&fix_windows_verbatim_for_gcc(&search_path.dir)),
+            }
+        }
+    }
+
+    let search_paths = OnceCell::new();
+    // All static and dynamic native library dependencies are linked to the local crate.
+    let link_static = true;
+    let link_dynamic = true;
+    add_native_libs_from_crate(
+        cmd,
+        sess,
+        archive_builder_builder,
+        codegen_results,
+        tmpdir,
+        &search_paths,
+        &Default::default(),
+        LOCAL_CRATE,
+        link_static,
+        link_dynamic,
+    );
+}
+
 fn add_upstream_rust_crates<'a>(
     cmd: &mut dyn Linker,
     sess: &'a Session,
@@ -2381,7 +2446,6 @@ fn add_upstream_rust_crates<'a>(
     // Linking to a rlib involves just passing it to the linker (the linker
     // will slurp up the object files inside), and linking to a dynamic library
     // involves just passing the right -l flag.
-
     let (_, data) = codegen_results
         .crate_info
         .dependency_formats
@@ -2389,348 +2453,236 @@ fn add_upstream_rust_crates<'a>(
         .find(|(ty, _)| *ty == crate_type)
         .expect("failed to find crate type in dependency format list");
 
-    // Invoke get_used_crates to ensure that we get a topological sorting of
-    // crates.
-    let deps = &codegen_results.crate_info.used_crates;
+    let search_paths = OnceCell::new();
+    for &cnum in &codegen_results.crate_info.used_crates {
+        // We may not pass all crates through to the linker. Some crates may appear statically in
+        // an existing dylib, meaning we'll pick up all the symbols from the dylib.
+        // We must always link crates `compiler_builtins` and `profiler_builtins` statically.
+        // Even if they were already included into a dylib
+        // (e.g. `libstd` when `-C prefer-dynamic` is used).
+        // FIXME: `dependency_formats` can report `profiler_builtins` as `NotLinked` for some
+        // reason, it shouldn't do that because `profiler_builtins` should indeed be linked.
+        let linkage = data[cnum.as_usize() - 1];
+        let link_static_crate = linkage == Linkage::Static
+            || (linkage == Linkage::IncludedFromDylib || linkage == Linkage::NotLinked)
+                && (codegen_results.crate_info.compiler_builtins == Some(cnum)
+                    || codegen_results.crate_info.profiler_runtime == Some(cnum));
 
-    let mut compiler_builtins = None;
-    let search_path = OnceCell::new();
-
-    for &cnum in deps.iter() {
-        // We may not pass all crates through to the linker. Some crates may
-        // appear statically in an existing dylib, meaning we'll pick up all the
-        // symbols from the dylib.
-        let src = &codegen_results.crate_info.used_crate_source[&cnum];
-        match data[cnum.as_usize() - 1] {
-            _ if codegen_results.crate_info.profiler_runtime == Some(cnum) => {
-                add_static_crate(
-                    cmd,
-                    sess,
-                    archive_builder_builder,
-                    codegen_results,
-                    tmpdir,
-                    cnum,
-                    &Default::default(),
-                );
-            }
-            // compiler-builtins are always placed last to ensure that they're
-            // linked correctly.
-            _ if codegen_results.crate_info.compiler_builtins == Some(cnum) => {
-                assert!(compiler_builtins.is_none());
-                compiler_builtins = Some(cnum);
-            }
-            Linkage::NotLinked | Linkage::IncludedFromDylib => {}
-            Linkage::Static => {
-                let bundled_libs = if sess.opts.unstable_opts.packed_bundled_libs {
-                    codegen_results.crate_info.native_libraries[&cnum]
+        let mut bundled_libs = Default::default();
+        match linkage {
+            Linkage::Static | Linkage::IncludedFromDylib | Linkage::NotLinked => {
+                if link_static_crate {
+                    bundled_libs = codegen_results.crate_info.native_libraries[&cnum]
                         .iter()
                         .filter_map(|lib| lib.filename)
-                        .collect::<FxHashSet<_>>()
-                } else {
-                    Default::default()
-                };
-                add_static_crate(
-                    cmd,
-                    sess,
-                    archive_builder_builder,
-                    codegen_results,
-                    tmpdir,
-                    cnum,
-                    &bundled_libs,
-                );
-
-                // Link static native libs with "-bundle" modifier only if the crate they originate from
-                // is being linked statically to the current crate.  If it's linked dynamically
-                // or is an rlib already included via some other dylib crate, the symbols from
-                // native libs will have already been included in that dylib.
-                //
-                // If `-Zlink-native-libraries=false` is set, then the assumption is that an
-                // external build system already has the native dependencies defined, and it
-                // will provide them to the linker itself.
-                if sess.opts.unstable_opts.link_native_libraries {
-                    if sess.opts.unstable_opts.packed_bundled_libs {
-                        // If rlib contains native libs as archives, unpack them to tmpdir.
-                        let rlib = &src.rlib.as_ref().unwrap().0;
-                        archive_builder_builder
-                            .extract_bundled_libs(rlib, tmpdir, &bundled_libs)
-                            .unwrap_or_else(|e| sess.fatal(e));
-                    }
-
-                    let mut last = (None, NativeLibKind::Unspecified, None);
-                    for lib in &codegen_results.crate_info.native_libraries[&cnum] {
-                        let Some(name) = lib.name else {
-                            continue;
-                        };
-                        let name = name.as_str();
-                        if !relevant_lib(sess, lib) {
-                            continue;
-                        }
-
-                        // Skip if this library is the same as the last.
-                        last = if (lib.name, lib.kind, lib.verbatim) == last {
-                            continue;
-                        } else {
-                            (lib.name, lib.kind, lib.verbatim)
-                        };
-
-                        match lib.kind {
-                            NativeLibKind::Static {
-                                bundle: Some(false),
-                                whole_archive: Some(true),
-                            } => {
-                                cmd.link_whole_staticlib(
-                                    name,
-                                    lib.verbatim.unwrap_or(false),
-                                    search_path.get_or_init(|| archive_search_paths(sess)),
-                                );
-                            }
-                            NativeLibKind::Static {
-                                bundle: Some(false),
-                                whole_archive: Some(false) | None,
-                            } => {
-                                // HACK/FIXME: Fixup a circular dependency between libgcc and libc
-                                // with glibc. This logic should be moved to the libc crate.
-                                if sess.target.os == "linux"
-                                    && sess.target.env == "gnu"
-                                    && name == "c"
-                                {
-                                    cmd.link_staticlib("gcc", false);
-                                }
-                                cmd.link_staticlib(name, lib.verbatim.unwrap_or(false));
-                            }
-                            NativeLibKind::LinkArg => {
-                                cmd.arg(name);
-                            }
-                            NativeLibKind::Dylib { .. }
-                            | NativeLibKind::Framework { .. }
-                            | NativeLibKind::Unspecified
-                            | NativeLibKind::RawDylib => {}
-                            NativeLibKind::Static { bundle: Some(true) | None, whole_archive } => {
-                                if sess.opts.unstable_opts.packed_bundled_libs {
-                                    // If rlib contains native libs as archives, they are unpacked to tmpdir.
-                                    let path = tmpdir.join(lib.filename.unwrap().as_str());
-                                    if whole_archive == Some(true) {
-                                        cmd.link_whole_rlib(&path);
-                                    } else {
-                                        cmd.link_rlib(&path);
-                                    }
-                                }
-                            }
-                        }
-                    }
+                        .collect();
+                    add_static_crate(
+                        cmd,
+                        sess,
+                        archive_builder_builder,
+                        codegen_results,
+                        tmpdir,
+                        cnum,
+                        &bundled_libs,
+                    );
                 }
             }
-            Linkage::Dynamic => add_dynamic_crate(cmd, sess, &src.dylib.as_ref().unwrap().0),
+            Linkage::Dynamic => {
+                let src = &codegen_results.crate_info.used_crate_source[&cnum];
+                add_dynamic_crate(cmd, sess, &src.dylib.as_ref().unwrap().0);
+            }
         }
-    }
 
-    // compiler-builtins are always placed last to ensure that they're
-    // linked correctly.
-    // We must always link the `compiler_builtins` crate statically. Even if it
-    // was already "included" in a dylib (e.g., `libstd` when `-C prefer-dynamic`
-    // is used)
-    if let Some(cnum) = compiler_builtins {
-        add_static_crate(
+        // Static libraries are linked for a subset of linked upstream crates.
+        // 1. If the upstream crate is a directly linked rlib then we must link the native library
+        // because the rlib is just an archive.
+        // 2. If the upstream crate is a dylib or a rlib linked through dylib, then we do not link
+        // the native library because it is already linked into the dylib, and even if
+        // inline/const/generic functions from the dylib can refer to symbols from the native
+        // library, those symbols should be exported and available from the dylib anyway.
+        // 3. Libraries bundled into `(compiler,profiler)_builtins` are special, see above.
+        let link_static = link_static_crate;
+        // Dynamic libraries are not linked here, see the FIXME in `add_upstream_native_libraries`.
+        let link_dynamic = false;
+        add_native_libs_from_crate(
             cmd,
             sess,
             archive_builder_builder,
             codegen_results,
             tmpdir,
+            &search_paths,
+            &bundled_libs,
             cnum,
-            &Default::default(),
-        );
-    }
-
-    // Converts a library file-stem into a cc -l argument
-    fn unlib<'a>(target: &Target, stem: &'a str) -> &'a str {
-        if stem.starts_with("lib") && !target.is_like_windows { &stem[3..] } else { stem }
-    }
-
-    // Adds the static "rlib" versions of all crates to the command line.
-    // There's a bit of magic which happens here specifically related to LTO,
-    // namely that we remove upstream object files.
-    //
-    // When performing LTO, almost(*) all of the bytecode from the upstream
-    // libraries has already been included in our object file output. As a
-    // result we need to remove the object files in the upstream libraries so
-    // the linker doesn't try to include them twice (or whine about duplicate
-    // symbols). We must continue to include the rest of the rlib, however, as
-    // it may contain static native libraries which must be linked in.
-    //
-    // (*) Crates marked with `#![no_builtins]` don't participate in LTO and
-    // their bytecode wasn't included. The object files in those libraries must
-    // still be passed to the linker.
-    //
-    // Note, however, that if we're not doing LTO we can just pass the rlib
-    // blindly to the linker (fast) because it's fine if it's not actually
-    // included as we're at the end of the dependency chain.
-    fn add_static_crate<'a>(
-        cmd: &mut dyn Linker,
-        sess: &'a Session,
-        archive_builder_builder: &dyn ArchiveBuilderBuilder,
-        codegen_results: &CodegenResults,
-        tmpdir: &Path,
-        cnum: CrateNum,
-        bundled_lib_file_names: &FxHashSet<Symbol>,
-    ) {
-        let src = &codegen_results.crate_info.used_crate_source[&cnum];
-        let cratepath = &src.rlib.as_ref().unwrap().0;
-
-        let mut link_upstream = |path: &Path| {
-            cmd.link_rlib(&fix_windows_verbatim_for_gcc(path));
-        };
-
-        // See the comment above in `link_staticlib` and `link_rlib` for why if
-        // there's a static library that's not relevant we skip all object
-        // files.
-        let native_libs = &codegen_results.crate_info.native_libraries[&cnum];
-        let skip_native = native_libs.iter().any(|lib| {
-            matches!(lib.kind, NativeLibKind::Static { bundle: None | Some(true), .. })
-                && !relevant_lib(sess, lib)
-        });
-
-        if (!are_upstream_rust_objects_already_included(sess)
-            || ignored_for_lto(sess, &codegen_results.crate_info, cnum))
-            && !skip_native
-        {
-            link_upstream(cratepath);
-            return;
-        }
-
-        let dst = tmpdir.join(cratepath.file_name().unwrap());
-        let name = cratepath.file_name().unwrap().to_str().unwrap();
-        let name = &name[3..name.len() - 5]; // chop off lib/.rlib
-        let bundled_lib_file_names = bundled_lib_file_names.clone();
-
-        sess.prof.generic_activity_with_arg("link_altering_rlib", name).run(|| {
-            let canonical_name = name.replace('-', "_");
-            let upstream_rust_objects_already_included =
-                are_upstream_rust_objects_already_included(sess);
-            let is_builtins = sess.target.no_builtins
-                || !codegen_results.crate_info.is_no_builtins.contains(&cnum);
-
-            let mut archive = archive_builder_builder.new_archive_builder(sess);
-            if let Err(e) = archive.add_archive(
-                cratepath,
-                Box::new(move |f| {
-                    if f == METADATA_FILENAME {
-                        return true;
-                    }
-
-                    let canonical = f.replace('-', "_");
-
-                    let is_rust_object =
-                        canonical.starts_with(&canonical_name) && looks_like_rust_object_file(&f);
-
-                    // If we've been requested to skip all native object files
-                    // (those not generated by the rust compiler) then we can skip
-                    // this file. See above for why we may want to do this.
-                    let skip_because_cfg_say_so = skip_native && !is_rust_object;
-
-                    // If we're performing LTO and this is a rust-generated object
-                    // file, then we don't need the object file as it's part of the
-                    // LTO module. Note that `#![no_builtins]` is excluded from LTO,
-                    // though, so we let that object file slide.
-                    let skip_because_lto =
-                        upstream_rust_objects_already_included && is_rust_object && is_builtins;
-
-                    // We skip native libraries because:
-                    // 1. This native libraries won't be used from the generated rlib,
-                    //    so we can throw them away to avoid the copying work.
-                    // 2. We can't allow it to be a single remaining entry in archive
-                    //    as some linkers may complain on that.
-                    if bundled_lib_file_names.contains(&Symbol::intern(f)) {
-                        return true;
-                    }
-
-                    if skip_because_cfg_say_so || skip_because_lto {
-                        return true;
-                    }
-
-                    false
-                }),
-            ) {
-                sess.fatal(&format!("failed to build archive from rlib: {}", e));
-            }
-            if archive.build(&dst) {
-                link_upstream(&dst);
-            }
-        });
-    }
-
-    // Same thing as above, but for dynamic crates instead of static crates.
-    fn add_dynamic_crate(cmd: &mut dyn Linker, sess: &Session, cratepath: &Path) {
-        // Just need to tell the linker about where the library lives and
-        // what its name is
-        let parent = cratepath.parent();
-        if let Some(dir) = parent {
-            cmd.include_path(&fix_windows_verbatim_for_gcc(dir));
-        }
-        let filestem = cratepath.file_stem().unwrap().to_str().unwrap();
-        cmd.link_rust_dylib(
-            &unlib(&sess.target, filestem),
-            parent.unwrap_or_else(|| Path::new("")),
+            link_static,
+            link_dynamic,
         );
     }
 }
 
-/// Link in all of our upstream crates' native dependencies. Remember that all of these upstream
-/// native dependencies are all non-static dependencies. We've got two cases then:
-///
-/// 1. The upstream crate is an rlib. In this case we *must* link in the native dependency because
-/// the rlib is just an archive.
-///
-/// 2. The upstream crate is a dylib. In order to use the dylib, we have to have the dependency
-/// present on the system somewhere. Thus, we don't gain a whole lot from not linking in the
-/// dynamic dependency to this crate as well.
-///
-/// The use case for this is a little subtle. In theory the native dependencies of a crate are
-/// purely an implementation detail of the crate itself, but the problem arises with generic and
-/// inlined functions. If a generic function calls a native function, then the generic function
-/// must be instantiated in the target crate, meaning that the native symbol must also be resolved
-/// in the target crate.
 fn add_upstream_native_libraries(
     cmd: &mut dyn Linker,
     sess: &Session,
+    archive_builder_builder: &dyn ArchiveBuilderBuilder,
     codegen_results: &CodegenResults,
+    tmpdir: &Path,
 ) {
-    let mut last = (None, NativeLibKind::Unspecified, None);
+    let search_path = OnceCell::new();
     for &cnum in &codegen_results.crate_info.used_crates {
-        for lib in codegen_results.crate_info.native_libraries[&cnum].iter() {
-            let Some(name) = lib.name else {
-                continue;
-            };
-            let name = name.as_str();
-            if !relevant_lib(sess, &lib) {
-                continue;
-            }
-
-            // Skip if this library is the same as the last.
-            last = if (lib.name, lib.kind, lib.verbatim) == last {
-                continue;
-            } else {
-                (lib.name, lib.kind, lib.verbatim)
-            };
-
-            let verbatim = lib.verbatim.unwrap_or(false);
-            match lib.kind {
-                NativeLibKind::Dylib { as_needed } => {
-                    cmd.link_dylib(name, verbatim, as_needed.unwrap_or(true))
-                }
-                NativeLibKind::Unspecified => cmd.link_dylib(name, verbatim, true),
-                NativeLibKind::Framework { as_needed } => {
-                    cmd.link_framework(name, as_needed.unwrap_or(true))
-                }
-                // ignore static native libraries here as we've
-                // already included them in add_local_native_libraries and
-                // add_upstream_rust_crates
-                NativeLibKind::Static { .. } => {}
-                NativeLibKind::RawDylib | NativeLibKind::LinkArg => {}
-            }
-        }
+        // Static libraries are not linked here, they are linked in `add_upstream_rust_crates`.
+        // FIXME: Merge this function to `add_upstream_rust_crates` so that all native libraries
+        // are linked together with their respective upstream crates, and in their originally
+        // specified order. This is slightly breaking due to our use of `--as-needed` (see crater
+        // results in https://github.com/rust-lang/rust/pull/102832#issuecomment-1279772306).
+        let link_static = false;
+        // Dynamic libraries are linked for all linked upstream crates.
+        // 1. If the upstream crate is a directly linked rlib then we must link the native library
+        // because the rlib is just an archive.
+        // 2. If the upstream crate is a dylib or a rlib linked through dylib, then we have to link
+        // the native library too because inline/const/generic functions from the dylib can refer
+        // to symbols from the native library, so the native library providing those symbols should
+        // be available when linking our final binary.
+        let link_dynamic = true;
+        add_native_libs_from_crate(
+            cmd,
+            sess,
+            archive_builder_builder,
+            codegen_results,
+            tmpdir,
+            &search_path,
+            &Default::default(),
+            cnum,
+            link_static,
+            link_dynamic,
+        );
     }
 }
 
+// Adds the static "rlib" versions of all crates to the command line.
+// There's a bit of magic which happens here specifically related to LTO,
+// namely that we remove upstream object files.
+//
+// When performing LTO, almost(*) all of the bytecode from the upstream
+// libraries has already been included in our object file output. As a
+// result we need to remove the object files in the upstream libraries so
+// the linker doesn't try to include them twice (or whine about duplicate
+// symbols). We must continue to include the rest of the rlib, however, as
+// it may contain static native libraries which must be linked in.
+//
+// (*) Crates marked with `#![no_builtins]` don't participate in LTO and
+// their bytecode wasn't included. The object files in those libraries must
+// still be passed to the linker.
+//
+// Note, however, that if we're not doing LTO we can just pass the rlib
+// blindly to the linker (fast) because it's fine if it's not actually
+// included as we're at the end of the dependency chain.
+fn add_static_crate<'a>(
+    cmd: &mut dyn Linker,
+    sess: &'a Session,
+    archive_builder_builder: &dyn ArchiveBuilderBuilder,
+    codegen_results: &CodegenResults,
+    tmpdir: &Path,
+    cnum: CrateNum,
+    bundled_lib_file_names: &FxHashSet<Symbol>,
+) {
+    let src = &codegen_results.crate_info.used_crate_source[&cnum];
+    let cratepath = &src.rlib.as_ref().unwrap().0;
+
+    let mut link_upstream = |path: &Path| {
+        cmd.link_rlib(&fix_windows_verbatim_for_gcc(path));
+    };
+
+    // See the comment above in `link_staticlib` and `link_rlib` for why if
+    // there's a static library that's not relevant we skip all object
+    // files.
+    let native_libs = &codegen_results.crate_info.native_libraries[&cnum];
+    let skip_native = native_libs.iter().any(|lib| {
+        matches!(lib.kind, NativeLibKind::Static { bundle: None | Some(true), .. })
+            && !relevant_lib(sess, lib)
+    });
+
+    if (!are_upstream_rust_objects_already_included(sess)
+        || ignored_for_lto(sess, &codegen_results.crate_info, cnum))
+        && !skip_native
+    {
+        link_upstream(cratepath);
+        return;
+    }
+
+    let dst = tmpdir.join(cratepath.file_name().unwrap());
+    let name = cratepath.file_name().unwrap().to_str().unwrap();
+    let name = &name[3..name.len() - 5]; // chop off lib/.rlib
+    let bundled_lib_file_names = bundled_lib_file_names.clone();
+
+    sess.prof.generic_activity_with_arg("link_altering_rlib", name).run(|| {
+        let canonical_name = name.replace('-', "_");
+        let upstream_rust_objects_already_included =
+            are_upstream_rust_objects_already_included(sess);
+        let is_builtins =
+            sess.target.no_builtins || !codegen_results.crate_info.is_no_builtins.contains(&cnum);
+
+        let mut archive = archive_builder_builder.new_archive_builder(sess);
+        if let Err(e) = archive.add_archive(
+            cratepath,
+            Box::new(move |f| {
+                if f == METADATA_FILENAME {
+                    return true;
+                }
+
+                let canonical = f.replace('-', "_");
+
+                let is_rust_object =
+                    canonical.starts_with(&canonical_name) && looks_like_rust_object_file(&f);
+
+                // If we've been requested to skip all native object files
+                // (those not generated by the rust compiler) then we can skip
+                // this file. See above for why we may want to do this.
+                let skip_because_cfg_say_so = skip_native && !is_rust_object;
+
+                // If we're performing LTO and this is a rust-generated object
+                // file, then we don't need the object file as it's part of the
+                // LTO module. Note that `#![no_builtins]` is excluded from LTO,
+                // though, so we let that object file slide.
+                let skip_because_lto =
+                    upstream_rust_objects_already_included && is_rust_object && is_builtins;
+
+                // We skip native libraries because:
+                // 1. This native libraries won't be used from the generated rlib,
+                //    so we can throw them away to avoid the copying work.
+                // 2. We can't allow it to be a single remaining entry in archive
+                //    as some linkers may complain on that.
+                if bundled_lib_file_names.contains(&Symbol::intern(f)) {
+                    return true;
+                }
+
+                if skip_because_cfg_say_so || skip_because_lto {
+                    return true;
+                }
+
+                false
+            }),
+        ) {
+            sess.fatal(&format!("failed to build archive from rlib: {}", e));
+        }
+        if archive.build(&dst) {
+            link_upstream(&dst);
+        }
+    });
+}
+
+// Same thing as above, but for dynamic crates instead of static crates.
+fn add_dynamic_crate(cmd: &mut dyn Linker, sess: &Session, cratepath: &Path) {
+    // Just need to tell the linker about where the library lives and
+    // what its name is
+    let parent = cratepath.parent();
+    if let Some(dir) = parent {
+        cmd.include_path(&fix_windows_verbatim_for_gcc(dir));
+    }
+    let stem = cratepath.file_stem().unwrap().to_str().unwrap();
+    // Convert library file-stem into a cc -l argument.
+    let prefix = if stem.starts_with("lib") && !sess.target.is_like_windows { 3 } else { 0 };
+    cmd.link_rust_dylib(&stem[prefix..], parent.unwrap_or_else(|| Path::new("")));
+}
+
 fn relevant_lib(sess: &Session, lib: &NativeLib) -> bool {
     match lib.cfg {
         Some(ref cfg) => rustc_attr::cfg_matches(cfg, &sess.parse_sess, CRATE_NODE_ID, None),
@@ -2782,14 +2734,14 @@ fn add_apple_sdk(cmd: &mut dyn Linker, sess: &Session, flavor: LinkerFlavor) {
         ("arm", "watchos") => "watchos",
         (_, "macos") => "macosx",
         _ => {
-            sess.err(&format!("unsupported arch `{}` for os `{}`", arch, os));
+            sess.emit_err(errors::UnsupportedArch { arch, os });
             return;
         }
     };
     let sdk_root = match get_apple_sdk_root(sdk_name) {
         Ok(s) => s,
         Err(e) => {
-            sess.err(&e);
+            sess.emit_err(e);
             return;
         }
     };
@@ -2805,7 +2757,7 @@ fn add_apple_sdk(cmd: &mut dyn Linker, sess: &Session, flavor: LinkerFlavor) {
     }
 }
 
-fn get_apple_sdk_root(sdk_name: &str) -> Result<String, String> {
+fn get_apple_sdk_root(sdk_name: &str) -> Result<String, errors::AppleSdkRootError<'_>> {
     // Following what clang does
     // (https://github.com/llvm/llvm-project/blob/
     // 296a80102a9b72c3eda80558fb78a3ed8849b341/clang/lib/Driver/ToolChains/Darwin.cpp#L1661-L1678)
@@ -2855,7 +2807,7 @@ fn get_apple_sdk_root(sdk_name: &str) -> Result<String, String> {
 
     match res {
         Ok(output) => Ok(output.trim().to_string()),
-        Err(e) => Err(format!("failed to get {} SDK path: {}", sdk_name, e)),
+        Err(error) => Err(errors::AppleSdkRootError::SdkPath { sdk_name, error }),
     }
 }
 
@@ -2888,7 +2840,7 @@ fn add_gcc_ld_path(cmd: &mut dyn Linker, sess: &Session, flavor: LinkerFlavor) {
                 }
             }
         } else {
-            sess.fatal("option `-Z gcc-ld` is used even though linker flavor is not gcc");
+            sess.emit_fatal(errors::OptionGccOnly);
         }
     }
 }
diff --git a/compiler/rustc_codegen_ssa/src/back/linker.rs b/compiler/rustc_codegen_ssa/src/back/linker.rs
index c49b19bdf009..7f0c2861f7e2 100644
--- a/compiler/rustc_codegen_ssa/src/back/linker.rs
+++ b/compiler/rustc_codegen_ssa/src/back/linker.rs
@@ -1260,11 +1260,11 @@ impl<'a> Linker for WasmLd<'a> {
     }
 
     fn link_whole_staticlib(&mut self, lib: &str, _verbatim: bool, _search_path: &[PathBuf]) {
-        self.cmd.arg("-l").arg(lib);
+        self.cmd.arg("--whole-archive").arg("-l").arg(lib).arg("--no-whole-archive");
     }
 
     fn link_whole_rlib(&mut self, lib: &Path) {
-        self.cmd.arg(lib);
+        self.cmd.arg("--whole-archive").arg(lib).arg("--no-whole-archive");
     }
 
     fn gc_sections(&mut self, _keep_metadata: bool) {
diff --git a/compiler/rustc_codegen_ssa/src/back/metadata.rs b/compiler/rustc_codegen_ssa/src/back/metadata.rs
index 99ddd1764785..780a38500368 100644
--- a/compiler/rustc_codegen_ssa/src/back/metadata.rs
+++ b/compiler/rustc_codegen_ssa/src/back/metadata.rs
@@ -60,7 +60,7 @@ impl MetadataLoader for DefaultMetadataLoader {
                     let data = entry
                         .data(data)
                         .map_err(|e| format!("failed to parse rlib '{}': {}", path.display(), e))?;
-                    return search_for_metadata(path, data, ".rmeta");
+                    return search_for_section(path, data, ".rmeta");
                 }
             }
 
@@ -69,11 +69,11 @@ impl MetadataLoader for DefaultMetadataLoader {
     }
 
     fn get_dylib_metadata(&self, _target: &Target, path: &Path) -> Result<MetadataRef, String> {
-        load_metadata_with(path, |data| search_for_metadata(path, data, ".rustc"))
+        load_metadata_with(path, |data| search_for_section(path, data, ".rustc"))
     }
 }
 
-fn search_for_metadata<'a>(
+pub(super) fn search_for_section<'a>(
     path: &Path,
     bytes: &'a [u8],
     section: &str,
@@ -223,7 +223,11 @@ pub enum MetadataPosition {
 // * ELF - All other targets are similar to Windows in that there's a
 //   `SHF_EXCLUDE` flag we can set on sections in an object file to get
 //   automatically removed from the final output.
-pub fn create_rmeta_file(sess: &Session, metadata: &[u8]) -> (Vec<u8>, MetadataPosition) {
+pub fn create_wrapper_file(
+    sess: &Session,
+    section_name: Vec<u8>,
+    data: &[u8],
+) -> (Vec<u8>, MetadataPosition) {
     let Some(mut file) = create_object_file(sess) else {
         // This is used to handle all "other" targets. This includes targets
         // in two categories:
@@ -241,11 +245,11 @@ pub fn create_rmeta_file(sess: &Session, metadata: &[u8]) -> (Vec<u8>, MetadataP
         // WebAssembly and for targets not supported by the `object` crate
         // yet it means that work will need to be done in the `object` crate
         // to add a case above.
-        return (metadata.to_vec(), MetadataPosition::Last);
+        return (data.to_vec(), MetadataPosition::Last);
     };
     let section = file.add_section(
         file.segment_name(StandardSegment::Debug).to_vec(),
-        b".rmeta".to_vec(),
+        section_name,
         SectionKind::Debug,
     );
     match file.format() {
@@ -259,7 +263,7 @@ pub fn create_rmeta_file(sess: &Session, metadata: &[u8]) -> (Vec<u8>, MetadataP
         }
         _ => {}
     };
-    file.append_section_data(section, metadata, 1);
+    file.append_section_data(section, data, 1);
     (file.write().unwrap(), MetadataPosition::First)
 }
 
diff --git a/compiler/rustc_codegen_ssa/src/back/symbol_export.rs b/compiler/rustc_codegen_ssa/src/back/symbol_export.rs
index c2ecc41601c8..752f6b1ef40c 100644
--- a/compiler/rustc_codegen_ssa/src/back/symbol_export.rs
+++ b/compiler/rustc_codegen_ssa/src/back/symbol_export.rs
@@ -193,8 +193,11 @@ fn exported_symbols_provider_local<'tcx>(
     }
 
     if tcx.allocator_kind(()).is_some() {
-        for method in ALLOCATOR_METHODS {
-            let symbol_name = format!("__rust_{}", method.name);
+        for symbol_name in ALLOCATOR_METHODS
+            .iter()
+            .map(|method| format!("__rust_{}", method.name))
+            .chain(["__rust_alloc_error_handler".to_string(), OomStrategy::SYMBOL.to_string()])
+        {
             let exported_symbol = ExportedSymbol::NoDefId(SymbolName::new(tcx, &symbol_name));
 
             symbols.push((
diff --git a/compiler/rustc_codegen_ssa/src/back/write.rs b/compiler/rustc_codegen_ssa/src/back/write.rs
index d0ac016b02e1..e3d28a1aca20 100644
--- a/compiler/rustc_codegen_ssa/src/back/write.rs
+++ b/compiler/rustc_codegen_ssa/src/back/write.rs
@@ -15,10 +15,8 @@ use rustc_data_structures::profiling::TimingGuard;
 use rustc_data_structures::profiling::VerboseTimingGuard;
 use rustc_data_structures::sync::Lrc;
 use rustc_errors::emitter::Emitter;
-use rustc_errors::{
-    translation::{to_fluent_args, Translate},
-    DiagnosticId, FatalError, Handler, Level,
-};
+use rustc_errors::{translation::Translate, DiagnosticId, FatalError, Handler, Level};
+use rustc_errors::{DiagnosticMessage, Style};
 use rustc_fs_util::link_or_copy;
 use rustc_hir::def_id::{CrateNum, LOCAL_CRATE};
 use rustc_incremental::{
@@ -38,6 +36,7 @@ use rustc_span::{BytePos, FileName, InnerSpan, Pos, Span};
 use rustc_target::spec::{MergeFunctions, SanitizerSet};
 
 use std::any::Any;
+use std::borrow::Cow;
 use std::fs;
 use std::io;
 use std::marker::PhantomData;
@@ -969,8 +968,11 @@ pub enum Message<B: WriteBackendMethods> {
     CodegenAborted,
 }
 
+type DiagnosticArgName<'source> = Cow<'source, str>;
+
 struct Diagnostic {
-    msg: String,
+    msg: Vec<(DiagnosticMessage, Style)>,
+    args: FxHashMap<DiagnosticArgName<'static>, rustc_errors::DiagnosticArgValue<'static>>,
     code: Option<DiagnosticId>,
     lvl: Level,
 }
@@ -1743,15 +1745,18 @@ impl Translate for SharedEmitter {
 
 impl Emitter for SharedEmitter {
     fn emit_diagnostic(&mut self, diag: &rustc_errors::Diagnostic) {
-        let fluent_args = to_fluent_args(diag.args());
+        let args: FxHashMap<Cow<'_, str>, rustc_errors::DiagnosticArgValue<'_>> =
+            diag.args().map(|(name, arg)| (name.clone(), arg.clone())).collect();
         drop(self.sender.send(SharedEmitterMessage::Diagnostic(Diagnostic {
-            msg: self.translate_messages(&diag.message, &fluent_args).to_string(),
+            msg: diag.message.clone(),
+            args: args.clone(),
             code: diag.code.clone(),
             lvl: diag.level(),
         })));
         for child in &diag.children {
             drop(self.sender.send(SharedEmitterMessage::Diagnostic(Diagnostic {
-                msg: self.translate_messages(&child.message, &fluent_args).to_string(),
+                msg: child.message.clone(),
+                args: args.clone(),
                 code: None,
                 lvl: child.level,
             })));
@@ -1782,10 +1787,11 @@ impl SharedEmitterMain {
             match message {
                 Ok(SharedEmitterMessage::Diagnostic(diag)) => {
                     let handler = sess.diagnostic();
-                    let mut d = rustc_errors::Diagnostic::new(diag.lvl, &diag.msg);
+                    let mut d = rustc_errors::Diagnostic::new_with_messages(diag.lvl, diag.msg);
                     if let Some(code) = diag.code {
                         d.code(code);
                     }
+                    d.replace_args(diag.args);
                     handler.emit_diagnostic(&mut d);
                 }
                 Ok(SharedEmitterMessage::InlineAsmError(cookie, msg, level, source)) => {
diff --git a/compiler/rustc_codegen_ssa/src/base.rs b/compiler/rustc_codegen_ssa/src/base.rs
index ff1eee37ad9c..4f396e970ad7 100644
--- a/compiler/rustc_codegen_ssa/src/base.rs
+++ b/compiler/rustc_codegen_ssa/src/base.rs
@@ -22,7 +22,6 @@ use rustc_data_structures::sync::ParallelIterator;
 use rustc_hir as hir;
 use rustc_hir::def_id::{DefId, LOCAL_CRATE};
 use rustc_hir::lang_items::LangItem;
-use rustc_hir::weak_lang_items::WEAK_ITEMS_SYMBOLS;
 use rustc_index::vec::Idx;
 use rustc_metadata::EncodedMetadata;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrs;
@@ -337,40 +336,26 @@ pub fn coerce_unsized_into<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
 
 pub fn cast_shift_expr_rhs<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
     bx: &mut Bx,
-    op: hir::BinOpKind,
-    lhs: Bx::Value,
-    rhs: Bx::Value,
-) -> Bx::Value {
-    cast_shift_rhs(bx, op, lhs, rhs)
-}
-
-fn cast_shift_rhs<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
-    bx: &mut Bx,
-    op: hir::BinOpKind,
     lhs: Bx::Value,
     rhs: Bx::Value,
 ) -> Bx::Value {
     // Shifts may have any size int on the rhs
-    if op.is_shift() {
-        let mut rhs_llty = bx.cx().val_ty(rhs);
-        let mut lhs_llty = bx.cx().val_ty(lhs);
-        if bx.cx().type_kind(rhs_llty) == TypeKind::Vector {
-            rhs_llty = bx.cx().element_type(rhs_llty)
-        }
-        if bx.cx().type_kind(lhs_llty) == TypeKind::Vector {
-            lhs_llty = bx.cx().element_type(lhs_llty)
-        }
-        let rhs_sz = bx.cx().int_width(rhs_llty);
-        let lhs_sz = bx.cx().int_width(lhs_llty);
-        if lhs_sz < rhs_sz {
-            bx.trunc(rhs, lhs_llty)
-        } else if lhs_sz > rhs_sz {
-            // FIXME (#1877: If in the future shifting by negative
-            // values is no longer undefined then this is wrong.
-            bx.zext(rhs, lhs_llty)
-        } else {
-            rhs
-        }
+    let mut rhs_llty = bx.cx().val_ty(rhs);
+    let mut lhs_llty = bx.cx().val_ty(lhs);
+    if bx.cx().type_kind(rhs_llty) == TypeKind::Vector {
+        rhs_llty = bx.cx().element_type(rhs_llty)
+    }
+    if bx.cx().type_kind(lhs_llty) == TypeKind::Vector {
+        lhs_llty = bx.cx().element_type(lhs_llty)
+    }
+    let rhs_sz = bx.cx().int_width(rhs_llty);
+    let lhs_sz = bx.cx().int_width(lhs_llty);
+    if lhs_sz < rhs_sz {
+        bx.trunc(rhs, lhs_llty)
+    } else if lhs_sz > rhs_sz {
+        // FIXME (#1877: If in the future shifting by negative
+        // values is no longer undefined then this is wrong.
+        bx.zext(rhs, lhs_llty)
     } else {
         rhs
     }
@@ -653,7 +638,14 @@ pub fn codegen_crate<B: ExtraBackendMethods>(
         let llmod_id =
             cgu_name_builder.build_cgu_name(LOCAL_CRATE, &["crate"], Some("allocator")).to_string();
         let module_llvm = tcx.sess.time("write_allocator_module", || {
-            backend.codegen_allocator(tcx, &llmod_id, kind, tcx.lang_items().oom().is_some())
+            backend.codegen_allocator(
+                tcx,
+                &llmod_id,
+                kind,
+                // If allocator_kind is Some then alloc_error_handler_kind must
+                // also be Some.
+                tcx.alloc_error_handler_kind(()).unwrap(),
+            )
         });
 
         Some(ModuleCodegen { name: llmod_id, module_llvm, kind: ModuleKind::Allocator })
@@ -841,20 +833,30 @@ impl CrateInfo {
         //
         // In order to get this left-to-right dependency ordering, we use the reverse
         // postorder of all crates putting the leaves at the right-most positions.
-        let used_crates = tcx
+        let mut compiler_builtins = None;
+        let mut used_crates: Vec<_> = tcx
             .postorder_cnums(())
             .iter()
             .rev()
             .copied()
-            .filter(|&cnum| !tcx.dep_kind(cnum).macros_only())
+            .filter(|&cnum| {
+                let link = !tcx.dep_kind(cnum).macros_only();
+                if link && tcx.is_compiler_builtins(cnum) {
+                    compiler_builtins = Some(cnum);
+                    return false;
+                }
+                link
+            })
             .collect();
+        // `compiler_builtins` are always placed last to ensure that they're linked correctly.
+        used_crates.extend(compiler_builtins);
 
         let mut info = CrateInfo {
             target_cpu,
             exported_symbols,
             linked_symbols,
             local_crate_name,
-            compiler_builtins: None,
+            compiler_builtins,
             profiler_runtime: None,
             is_no_builtins: Default::default(),
             native_libraries: Default::default(),
@@ -880,9 +882,6 @@ impl CrateInfo {
 
             let used_crate_source = tcx.used_crate_source(cnum);
             info.used_crate_source.insert(cnum, used_crate_source.clone());
-            if tcx.is_compiler_builtins(cnum) {
-                info.compiler_builtins = Some(cnum);
-            }
             if tcx.is_profiler_runtime(cnum) {
                 info.profiler_runtime = Some(cnum);
             }
@@ -901,14 +900,14 @@ impl CrateInfo {
         // by the compiler, but that's ok because all this stuff is unstable anyway.
         let target = &tcx.sess.target;
         if !are_upstream_rust_objects_already_included(tcx.sess) {
-            let missing_weak_lang_items: FxHashSet<&Symbol> = info
+            let missing_weak_lang_items: FxHashSet<Symbol> = info
                 .used_crates
                 .iter()
-                .flat_map(|cnum| {
-                    tcx.missing_lang_items(*cnum)
-                        .iter()
-                        .filter(|l| lang_items::required(tcx, **l))
-                        .filter_map(|item| WEAK_ITEMS_SYMBOLS.get(item))
+                .flat_map(|&cnum| tcx.missing_lang_items(cnum))
+                .filter(|l| l.is_weak())
+                .filter_map(|&l| {
+                    let name = l.link_name()?;
+                    lang_items::required(tcx, l).then_some(name)
                 })
                 .collect();
             let prefix = if target.is_like_windows && target.arch == "x86" { "_" } else { "" };
diff --git a/compiler/rustc_codegen_ssa/src/common.rs b/compiler/rustc_codegen_ssa/src/common.rs
index 8ca1a6084cf6..71f9179d02cc 100644
--- a/compiler/rustc_codegen_ssa/src/common.rs
+++ b/compiler/rustc_codegen_ssa/src/common.rs
@@ -1,7 +1,6 @@
 #![allow(non_camel_case_types)]
 
 use rustc_errors::struct_span_err;
-use rustc_hir as hir;
 use rustc_hir::LangItem;
 use rustc_middle::mir::interpret::ConstValue;
 use rustc_middle::ty::{self, layout::TyAndLayout, Ty, TyCtxt};
@@ -140,7 +139,7 @@ pub fn build_unchecked_lshift<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
     lhs: Bx::Value,
     rhs: Bx::Value,
 ) -> Bx::Value {
-    let rhs = base::cast_shift_expr_rhs(bx, hir::BinOpKind::Shl, lhs, rhs);
+    let rhs = base::cast_shift_expr_rhs(bx, lhs, rhs);
     // #1877, #10183: Ensure that input is always valid
     let rhs = shift_mask_rhs(bx, rhs);
     bx.shl(lhs, rhs)
@@ -152,7 +151,7 @@ pub fn build_unchecked_rshift<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
     lhs: Bx::Value,
     rhs: Bx::Value,
 ) -> Bx::Value {
-    let rhs = base::cast_shift_expr_rhs(bx, hir::BinOpKind::Shr, lhs, rhs);
+    let rhs = base::cast_shift_expr_rhs(bx, lhs, rhs);
     // #1877, #10183: Ensure that input is always valid
     let rhs = shift_mask_rhs(bx, rhs);
     let is_signed = lhs_t.is_signed();
diff --git a/compiler/rustc_codegen_ssa/src/debuginfo/type_names.rs b/compiler/rustc_codegen_ssa/src/debuginfo/type_names.rs
index e05646e1e86a..8647fbace2a7 100644
--- a/compiler/rustc_codegen_ssa/src/debuginfo/type_names.rs
+++ b/compiler/rustc_codegen_ssa/src/debuginfo/type_names.rs
@@ -59,7 +59,13 @@ fn push_debuginfo_type_name<'tcx>(
     match *t.kind() {
         ty::Bool => output.push_str("bool"),
         ty::Char => output.push_str("char"),
-        ty::Str => output.push_str("str"),
+        ty::Str => {
+            if cpp_like_debuginfo {
+                output.push_str("str$")
+            } else {
+                output.push_str("str")
+            }
+        }
         ty::Never => {
             if cpp_like_debuginfo {
                 output.push_str("never$");
@@ -152,25 +158,19 @@ fn push_debuginfo_type_name<'tcx>(
             }
         }
         ty::Ref(_, inner_type, mutbl) => {
-            // Slices and `&str` are treated like C++ pointers when computing debug
-            // info for MSVC debugger. However, wrapping these types' names in a synthetic type
-            // causes the .natvis engine for WinDbg to fail to display their data, so we opt these
-            // types out to aid debugging in MSVC.
-            let is_slice_or_str = matches!(*inner_type.kind(), ty::Slice(_) | ty::Str);
-
-            if !cpp_like_debuginfo {
-                output.push('&');
-                output.push_str(mutbl.prefix_str());
-            } else if !is_slice_or_str {
+            if cpp_like_debuginfo {
                 match mutbl {
                     Mutability::Not => output.push_str("ref$<"),
                     Mutability::Mut => output.push_str("ref_mut$<"),
                 }
+            } else {
+                output.push('&');
+                output.push_str(mutbl.prefix_str());
             }
 
             push_debuginfo_type_name(tcx, inner_type, qualified, output, visited);
 
-            if cpp_like_debuginfo && !is_slice_or_str {
+            if cpp_like_debuginfo {
                 push_close_angle_bracket(cpp_like_debuginfo, output);
             }
         }
@@ -195,7 +195,7 @@ fn push_debuginfo_type_name<'tcx>(
         }
         ty::Slice(inner_type) => {
             if cpp_like_debuginfo {
-                output.push_str("slice$<");
+                output.push_str("slice2$<");
             } else {
                 output.push('[');
             }
diff --git a/compiler/rustc_codegen_ssa/src/errors.rs b/compiler/rustc_codegen_ssa/src/errors.rs
index ebb531f1c43a..bfc4515de098 100644
--- a/compiler/rustc_codegen_ssa/src/errors.rs
+++ b/compiler/rustc_codegen_ssa/src/errors.rs
@@ -354,3 +354,179 @@ impl IntoDiagnostic<'_> for LinkingFailed<'_> {
         diag
     }
 }
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_link_exe_unexpected_error)]
+pub struct LinkExeUnexpectedError;
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_repair_vs_build_tools)]
+pub struct RepairVSBuildTools;
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_missing_cpp_build_tool_component)]
+pub struct MissingCppBuildToolComponent;
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_select_cpp_build_tool_workload)]
+pub struct SelectCppBuildToolWorkload;
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_visual_studio_not_installed)]
+pub struct VisualStudioNotInstalled;
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_linker_not_found)]
+#[note]
+pub struct LinkerNotFound {
+    pub linker_path: PathBuf,
+    pub error: Error,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_unable_to_exe_linker)]
+#[note]
+#[note(command_note)]
+pub struct UnableToExeLinker {
+    pub linker_path: PathBuf,
+    pub error: Error,
+    pub command_formatted: String,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_msvc_missing_linker)]
+pub struct MsvcMissingLinker;
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_check_installed_visual_studio)]
+pub struct CheckInstalledVisualStudio;
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_unsufficient_vs_code_product)]
+pub struct UnsufficientVSCodeProduct;
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_processing_dymutil_failed)]
+#[note]
+pub struct ProcessingDymutilFailed {
+    pub status: ExitStatus,
+    pub output: String,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_unable_to_run_dsymutil)]
+#[note]
+pub struct UnableToRunDsymutil {
+    pub error: Error,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_stripping_debu_info_failed)]
+#[note]
+pub struct StrippingDebugInfoFailed<'a> {
+    pub util: &'a str,
+    pub status: ExitStatus,
+    pub output: String,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_unable_to_run)]
+pub struct UnableToRun<'a> {
+    pub util: &'a str,
+    pub error: Error,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_linker_file_stem)]
+pub struct LinkerFileStem;
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_static_library_native_artifacts)]
+pub struct StaticLibraryNativeArtifacts;
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_native_static_libs)]
+pub struct NativeStaticLibs {
+    pub arguments: String,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_link_script_unavailable)]
+pub struct LinkScriptUnavailable;
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_link_script_write_failure)]
+pub struct LinkScriptWriteFailure {
+    pub path: PathBuf,
+    pub error: Error,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_failed_to_write)]
+pub struct FailedToWrite {
+    pub path: PathBuf,
+    pub error: Error,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_unable_to_write_debugger_visualizer)]
+pub struct UnableToWriteDebuggerVisualizer {
+    pub path: PathBuf,
+    pub error: Error,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_rlib_archive_build_failure)]
+pub struct RlibArchiveBuildFailure {
+    pub error: Error,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_option_gcc_only)]
+pub struct OptionGccOnly;
+
+#[derive(Diagnostic)]
+pub enum ExtractBundledLibsError<'a> {
+    #[diag(codegen_ssa_extract_bundled_libs_open_file)]
+    OpenFile { rlib: &'a Path, error: Box<dyn std::error::Error> },
+
+    #[diag(codegen_ssa_extract_bundled_libs_mmap_file)]
+    MmapFile { rlib: &'a Path, error: Box<dyn std::error::Error> },
+
+    #[diag(codegen_ssa_extract_bundled_libs_parse_archive)]
+    ParseArchive { rlib: &'a Path, error: Box<dyn std::error::Error> },
+
+    #[diag(codegen_ssa_extract_bundled_libs_read_entry)]
+    ReadEntry { rlib: &'a Path, error: Box<dyn std::error::Error> },
+
+    #[diag(codegen_ssa_extract_bundled_libs_archive_member)]
+    ArchiveMember { rlib: &'a Path, error: Box<dyn std::error::Error> },
+
+    #[diag(codegen_ssa_extract_bundled_libs_convert_name)]
+    ConvertName { rlib: &'a Path, error: Box<dyn std::error::Error> },
+
+    #[diag(codegen_ssa_extract_bundled_libs_write_file)]
+    WriteFile { rlib: &'a Path, error: Box<dyn std::error::Error> },
+
+    #[diag(codegen_ssa_extract_bundled_libs_write_file)]
+    ExtractSection { rlib: &'a Path, error: Box<dyn std::error::Error> },
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_unsupported_arch)]
+pub struct UnsupportedArch<'a> {
+    pub arch: &'a str,
+    pub os: &'a str,
+}
+
+#[derive(Diagnostic)]
+pub enum AppleSdkRootError<'a> {
+    #[diag(codegen_ssa_apple_sdk_error_sdk_path)]
+    SdkPath { sdk_name: &'a str, error: Error },
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_read_file)]
+pub struct ReadFileError {
+    pub message: std::io::Error,
+}
diff --git a/compiler/rustc_codegen_ssa/src/glue.rs b/compiler/rustc_codegen_ssa/src/glue.rs
index e6f402ef19d8..6015d48decae 100644
--- a/compiler/rustc_codegen_ssa/src/glue.rs
+++ b/compiler/rustc_codegen_ssa/src/glue.rs
@@ -15,7 +15,7 @@ pub fn size_and_align_of_dst<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
 ) -> (Bx::Value, Bx::Value) {
     let layout = bx.layout_of(t);
     debug!("size_and_align_of_dst(ty={}, info={:?}): layout: {:?}", t, info, layout);
-    if !layout.is_unsized() {
+    if layout.is_sized() {
         let size = bx.const_usize(layout.size.bytes());
         let align = bx.const_usize(layout.align.abi.bytes());
         return (size, align);
diff --git a/compiler/rustc_codegen_ssa/src/mir/block.rs b/compiler/rustc_codegen_ssa/src/mir/block.rs
index bd4f0cac7eb4..0802067cde65 100644
--- a/compiler/rustc_codegen_ssa/src/mir/block.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/block.rs
@@ -17,6 +17,7 @@ use rustc_middle::mir::{self, AssertKind, SwitchTargets};
 use rustc_middle::ty::layout::{HasTyCtxt, LayoutOf};
 use rustc_middle::ty::print::{with_no_trimmed_paths, with_no_visible_paths};
 use rustc_middle::ty::{self, Instance, Ty, TypeVisitable};
+use rustc_session::config::OptLevel;
 use rustc_span::source_map::Span;
 use rustc_span::{sym, Symbol};
 use rustc_symbol_mangling::typeid::typeid_for_fnabi;
@@ -63,7 +64,9 @@ impl<'a, 'tcx> TerminatorCodegenHelper<'tcx> {
         }
     }
 
-    fn lltarget<Bx: BuilderMethods<'a, 'tcx>>(
+    /// Get a basic block (creating it if necessary), possibly with a landing
+    /// pad next to it.
+    fn llbb_with_landing_pad<Bx: BuilderMethods<'a, 'tcx>>(
         &self,
         fx: &mut FunctionCx<'a, 'tcx, Bx>,
         target: mir::BasicBlock,
@@ -73,32 +76,36 @@ impl<'a, 'tcx> TerminatorCodegenHelper<'tcx> {
         let target_funclet = fx.cleanup_kinds[target].funclet_bb(target);
         match (self.funclet_bb, target_funclet) {
             (None, None) => (lltarget, false),
-            (Some(f), Some(t_f)) if f == t_f || !base::wants_msvc_seh(fx.cx.tcx().sess) => {
-                (lltarget, false)
-            }
             // jump *into* cleanup - need a landing pad if GNU, cleanup pad if MSVC
             (None, Some(_)) => (fx.landing_pad_for(target), false),
             (Some(_), None) => span_bug!(span, "{:?} - jump out of cleanup?", self.terminator),
-            (Some(_), Some(_)) => (fx.landing_pad_for(target), true),
+            (Some(f), Some(t_f)) => {
+                if f == t_f || !base::wants_msvc_seh(fx.cx.tcx().sess) {
+                    (lltarget, false)
+                } else {
+                    (fx.landing_pad_for(target), true)
+                }
+            }
         }
     }
 
-    /// Create a basic block.
-    fn llblock<Bx: BuilderMethods<'a, 'tcx>>(
+    /// Get a basic block (creating it if necessary), possibly with cleanup
+    /// stuff in it or next to it.
+    fn llbb_with_cleanup<Bx: BuilderMethods<'a, 'tcx>>(
         &self,
         fx: &mut FunctionCx<'a, 'tcx, Bx>,
         target: mir::BasicBlock,
     ) -> Bx::BasicBlock {
-        let (lltarget, is_cleanupret) = self.lltarget(fx, target);
+        let (lltarget, is_cleanupret) = self.llbb_with_landing_pad(fx, target);
         if is_cleanupret {
             // MSVC cross-funclet jump - need a trampoline
-
-            debug!("llblock: creating cleanup trampoline for {:?}", target);
+            debug_assert!(base::wants_msvc_seh(fx.cx.tcx().sess));
+            debug!("llbb_with_cleanup: creating cleanup trampoline for {:?}", target);
             let name = &format!("{:?}_cleanup_trampoline_{:?}", self.bb, target);
-            let trampoline = Bx::append_block(fx.cx, fx.llfn, name);
-            let mut trampoline_bx = Bx::build(fx.cx, trampoline);
+            let trampoline_llbb = Bx::append_block(fx.cx, fx.llfn, name);
+            let mut trampoline_bx = Bx::build(fx.cx, trampoline_llbb);
             trampoline_bx.cleanup_ret(self.funclet(fx).unwrap(), Some(lltarget));
-            trampoline
+            trampoline_llbb
         } else {
             lltarget
         }
@@ -110,10 +117,11 @@ impl<'a, 'tcx> TerminatorCodegenHelper<'tcx> {
         bx: &mut Bx,
         target: mir::BasicBlock,
     ) {
-        let (lltarget, is_cleanupret) = self.lltarget(fx, target);
+        let (lltarget, is_cleanupret) = self.llbb_with_landing_pad(fx, target);
         if is_cleanupret {
-            // micro-optimization: generate a `ret` rather than a jump
+            // MSVC micro-optimization: generate a `ret` rather than a jump
             // to a trampoline.
+            debug_assert!(base::wants_msvc_seh(fx.cx.tcx().sess));
             bx.cleanup_ret(self.funclet(fx).unwrap(), Some(lltarget));
         } else {
             bx.br(lltarget);
@@ -138,7 +146,7 @@ impl<'a, 'tcx> TerminatorCodegenHelper<'tcx> {
         let fn_ty = bx.fn_decl_backend_type(&fn_abi);
 
         let unwind_block = if let Some(cleanup) = cleanup.filter(|_| fn_abi.can_unwind) {
-            Some(self.llblock(fx, cleanup))
+            Some(self.llbb_with_cleanup(fx, cleanup))
         } else if fx.mir[self.bb].is_cleanup
             && fn_abi.can_unwind
             && !base::wants_msvc_seh(fx.cx.tcx().sess)
@@ -231,7 +239,7 @@ impl<'a, 'tcx> TerminatorCodegenHelper<'tcx> {
                 options,
                 line_spans,
                 instance,
-                Some((ret_llbb, self.llblock(fx, cleanup), self.funclet(fx))),
+                Some((ret_llbb, self.llbb_with_cleanup(fx, cleanup), self.funclet(fx))),
             );
         } else {
             bx.codegen_inline_asm(template, &operands, options, line_spans, instance, None);
@@ -279,12 +287,13 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         assert_eq!(discr.layout.ty, switch_ty);
         let mut target_iter = targets.iter();
         if target_iter.len() == 1 {
-            // If there are two targets (one conditional, one fallback), emit br instead of switch
+            // If there are two targets (one conditional, one fallback), emit `br` instead of
+            // `switch`.
             let (test_value, target) = target_iter.next().unwrap();
-            let lltrue = helper.llblock(self, target);
-            let llfalse = helper.llblock(self, targets.otherwise());
+            let lltrue = helper.llbb_with_cleanup(self, target);
+            let llfalse = helper.llbb_with_cleanup(self, targets.otherwise());
             if switch_ty == bx.tcx().types.bool {
-                // Don't generate trivial icmps when switching on bool
+                // Don't generate trivial icmps when switching on bool.
                 match test_value {
                     0 => bx.cond_br(discr.immediate(), llfalse, lltrue),
                     1 => bx.cond_br(discr.immediate(), lltrue, llfalse),
@@ -296,11 +305,35 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                 let cmp = bx.icmp(IntPredicate::IntEQ, discr.immediate(), llval);
                 bx.cond_br(cmp, lltrue, llfalse);
             }
+        } else if self.cx.sess().opts.optimize == OptLevel::No
+            && target_iter.len() == 2
+            && self.mir[targets.otherwise()].is_empty_unreachable()
+        {
+            // In unoptimized builds, if there are two normal targets and the `otherwise` target is
+            // an unreachable BB, emit `br` instead of `switch`. This leaves behind the unreachable
+            // BB, which will usually (but not always) be dead code.
+            //
+            // Why only in unoptimized builds?
+            // - In unoptimized builds LLVM uses FastISel which does not support switches, so it
+            //   must fall back to the to the slower SelectionDAG isel. Therefore, using `br` gives
+            //   significant compile time speedups for unoptimized builds.
+            // - In optimized builds the above doesn't hold, and using `br` sometimes results in
+            //   worse generated code because LLVM can no longer tell that the value being switched
+            //   on can only have two values, e.g. 0 and 1.
+            //
+            let (test_value1, target1) = target_iter.next().unwrap();
+            let (_test_value2, target2) = target_iter.next().unwrap();
+            let ll1 = helper.llbb_with_cleanup(self, target1);
+            let ll2 = helper.llbb_with_cleanup(self, target2);
+            let switch_llty = bx.immediate_backend_type(bx.layout_of(switch_ty));
+            let llval = bx.const_uint_big(switch_llty, test_value1);
+            let cmp = bx.icmp(IntPredicate::IntEQ, discr.immediate(), llval);
+            bx.cond_br(cmp, ll1, ll2);
         } else {
             bx.switch(
                 discr.immediate(),
-                helper.llblock(self, targets.otherwise()),
-                target_iter.map(|(value, target)| (value, helper.llblock(self, target))),
+                helper.llbb_with_cleanup(self, targets.otherwise()),
+                target_iter.map(|(value, target)| (value, helper.llbb_with_cleanup(self, target))),
             );
         }
     }
@@ -530,7 +563,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         let cond = bx.expect(cond, expected);
 
         // Create the failure block and the conditional branch to it.
-        let lltarget = helper.llblock(self, target);
+        let lltarget = helper.llbb_with_cleanup(self, target);
         let panic_block = bx.append_sibling_block("panic");
         if expected {
             bx.cond_br(cond, lltarget, panic_block);
@@ -1459,20 +1492,20 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                 //          bar();
                 //      }
                 Some(&mir::TerminatorKind::Abort) => {
-                    let cs_bb =
+                    let cs_llbb =
                         Bx::append_block(self.cx, self.llfn, &format!("cs_funclet{:?}", bb));
-                    let cp_bb =
+                    let cp_llbb =
                         Bx::append_block(self.cx, self.llfn, &format!("cp_funclet{:?}", bb));
-                    ret_llbb = cs_bb;
+                    ret_llbb = cs_llbb;
 
-                    let mut cs_bx = Bx::build(self.cx, cs_bb);
-                    let cs = cs_bx.catch_switch(None, None, &[cp_bb]);
+                    let mut cs_bx = Bx::build(self.cx, cs_llbb);
+                    let cs = cs_bx.catch_switch(None, None, &[cp_llbb]);
 
                     // The "null" here is actually a RTTI type descriptor for the
                     // C++ personality function, but `catch (...)` has no type so
                     // it's null. The 64 here is actually a bitfield which
                     // represents that this is a catch-all block.
-                    let mut cp_bx = Bx::build(self.cx, cp_bb);
+                    let mut cp_bx = Bx::build(self.cx, cp_llbb);
                     let null = cp_bx.const_null(
                         cp_bx.type_i8p_ext(cp_bx.cx().data_layout().instruction_address_space),
                     );
@@ -1481,10 +1514,10 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                     cp_bx.br(llbb);
                 }
                 _ => {
-                    let cleanup_bb =
+                    let cleanup_llbb =
                         Bx::append_block(self.cx, self.llfn, &format!("funclet_{:?}", bb));
-                    ret_llbb = cleanup_bb;
-                    let mut cleanup_bx = Bx::build(self.cx, cleanup_bb);
+                    ret_llbb = cleanup_llbb;
+                    let mut cleanup_bx = Bx::build(self.cx, cleanup_llbb);
                     funclet = cleanup_bx.cleanup_pad(None, &[]);
                     cleanup_bx.br(llbb);
                 }
@@ -1492,19 +1525,20 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
             self.funclets[bb] = Some(funclet);
             ret_llbb
         } else {
-            let bb = Bx::append_block(self.cx, self.llfn, "cleanup");
-            let mut bx = Bx::build(self.cx, bb);
+            let cleanup_llbb = Bx::append_block(self.cx, self.llfn, "cleanup");
+            let mut cleanup_bx = Bx::build(self.cx, cleanup_llbb);
 
             let llpersonality = self.cx.eh_personality();
             let llretty = self.landing_pad_type();
-            let lp = bx.cleanup_landing_pad(llretty, llpersonality);
+            let lp = cleanup_bx.cleanup_landing_pad(llretty, llpersonality);
 
-            let slot = self.get_personality_slot(&mut bx);
-            slot.storage_live(&mut bx);
-            Pair(bx.extract_value(lp, 0), bx.extract_value(lp, 1)).store(&mut bx, slot);
+            let slot = self.get_personality_slot(&mut cleanup_bx);
+            slot.storage_live(&mut cleanup_bx);
+            Pair(cleanup_bx.extract_value(lp, 0), cleanup_bx.extract_value(lp, 1))
+                .store(&mut cleanup_bx, slot);
 
-            bx.br(llbb);
-            bx.llbb()
+            cleanup_bx.br(llbb);
+            cleanup_llbb
         }
     }
 
diff --git a/compiler/rustc_codegen_ssa/src/mir/mod.rs b/compiler/rustc_codegen_ssa/src/mir/mod.rs
index 2b931bfc91d6..da9aaf00ecf6 100644
--- a/compiler/rustc_codegen_ssa/src/mir/mod.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/mod.rs
@@ -148,10 +148,10 @@ pub fn codegen_mir<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
     let debug_context = cx.create_function_debug_context(instance, &fn_abi, llfn, &mir);
 
     let start_llbb = Bx::append_block(cx, llfn, "start");
-    let mut bx = Bx::build(cx, start_llbb);
+    let mut start_bx = Bx::build(cx, start_llbb);
 
     if mir.basic_blocks.iter().any(|bb| bb.is_cleanup) {
-        bx.set_personality_fn(cx.eh_personality());
+        start_bx.set_personality_fn(cx.eh_personality());
     }
 
     let cleanup_kinds = analyze::cleanup_kinds(&mir);
@@ -180,7 +180,7 @@ pub fn codegen_mir<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
         caller_location: None,
     };
 
-    fx.per_local_var_debug_info = fx.compute_per_local_var_debug_info(&mut bx);
+    fx.per_local_var_debug_info = fx.compute_per_local_var_debug_info(&mut start_bx);
 
     // Evaluate all required consts; codegen later assumes that CTFE will never fail.
     let mut all_consts_ok = true;
@@ -206,29 +206,29 @@ pub fn codegen_mir<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
 
     // Allocate variable and temp allocas
     fx.locals = {
-        let args = arg_local_refs(&mut bx, &mut fx, &memory_locals);
+        let args = arg_local_refs(&mut start_bx, &mut fx, &memory_locals);
 
         let mut allocate_local = |local| {
             let decl = &mir.local_decls[local];
-            let layout = bx.layout_of(fx.monomorphize(decl.ty));
+            let layout = start_bx.layout_of(fx.monomorphize(decl.ty));
             assert!(!layout.ty.has_erasable_regions());
 
             if local == mir::RETURN_PLACE && fx.fn_abi.ret.is_indirect() {
                 debug!("alloc: {:?} (return place) -> place", local);
-                let llretptr = bx.get_param(0);
+                let llretptr = start_bx.get_param(0);
                 return LocalRef::Place(PlaceRef::new_sized(llretptr, layout));
             }
 
             if memory_locals.contains(local) {
                 debug!("alloc: {:?} -> place", local);
                 if layout.is_unsized() {
-                    LocalRef::UnsizedPlace(PlaceRef::alloca_unsized_indirect(&mut bx, layout))
+                    LocalRef::UnsizedPlace(PlaceRef::alloca_unsized_indirect(&mut start_bx, layout))
                 } else {
-                    LocalRef::Place(PlaceRef::alloca(&mut bx, layout))
+                    LocalRef::Place(PlaceRef::alloca(&mut start_bx, layout))
                 }
             } else {
                 debug!("alloc: {:?} -> operand", local);
-                LocalRef::new_operand(&mut bx, layout)
+                LocalRef::new_operand(&mut start_bx, layout)
             }
         };
 
@@ -240,7 +240,7 @@ pub fn codegen_mir<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
     };
 
     // Apply debuginfo to the newly allocated locals.
-    fx.debug_introduce_locals(&mut bx);
+    fx.debug_introduce_locals(&mut start_bx);
 
     // Codegen the body of each block using reverse postorder
     for (bb, _) in traversal::reverse_postorder(&mir) {
diff --git a/compiler/rustc_codegen_ssa/src/mir/place.rs b/compiler/rustc_codegen_ssa/src/mir/place.rs
index 9c18df5643f1..908555385891 100644
--- a/compiler/rustc_codegen_ssa/src/mir/place.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/place.rs
@@ -29,7 +29,7 @@ pub struct PlaceRef<'tcx, V> {
 
 impl<'a, 'tcx, V: CodegenObject> PlaceRef<'tcx, V> {
     pub fn new_sized(llval: V, layout: TyAndLayout<'tcx>) -> PlaceRef<'tcx, V> {
-        assert!(!layout.is_unsized());
+        assert!(layout.is_sized());
         PlaceRef { llval, llextra: None, layout, align: layout.align.abi }
     }
 
@@ -38,7 +38,7 @@ impl<'a, 'tcx, V: CodegenObject> PlaceRef<'tcx, V> {
         layout: TyAndLayout<'tcx>,
         align: Align,
     ) -> PlaceRef<'tcx, V> {
-        assert!(!layout.is_unsized());
+        assert!(layout.is_sized());
         PlaceRef { llval, llextra: None, layout, align }
     }
 
@@ -48,7 +48,7 @@ impl<'a, 'tcx, V: CodegenObject> PlaceRef<'tcx, V> {
         bx: &mut Bx,
         layout: TyAndLayout<'tcx>,
     ) -> Self {
-        assert!(!layout.is_unsized(), "tried to statically allocate unsized place");
+        assert!(layout.is_sized(), "tried to statically allocate unsized place");
         let tmp = bx.alloca(bx.cx().backend_type(layout), layout.align.abi);
         Self::new_sized(tmp, layout)
     }
@@ -145,7 +145,7 @@ impl<'a, 'tcx, V: CodegenObject> PlaceRef<'tcx, V> {
                 );
                 return simple();
             }
-            _ if !field.is_unsized() => return simple(),
+            _ if field.is_sized() => return simple(),
             ty::Slice(..) | ty::Str | ty::Foreign(..) => return simple(),
             ty::Adt(def, _) => {
                 if def.repr().packed() {
@@ -209,7 +209,9 @@ impl<'a, 'tcx, V: CodegenObject> PlaceRef<'tcx, V> {
         bx: &mut Bx,
         cast_to: Ty<'tcx>,
     ) -> V {
-        let cast_to = bx.cx().immediate_backend_type(bx.cx().layout_of(cast_to));
+        let cast_to_layout = bx.cx().layout_of(cast_to);
+        let cast_to_size = cast_to_layout.layout.size();
+        let cast_to = bx.cx().immediate_backend_type(cast_to_layout);
         if self.layout.abi.is_uninhabited() {
             return bx.cx().const_undef(cast_to);
         }
@@ -229,7 +231,8 @@ impl<'a, 'tcx, V: CodegenObject> PlaceRef<'tcx, V> {
 
         // Read the tag/niche-encoded discriminant from memory.
         let tag = self.project_field(bx, tag_field);
-        let tag = bx.load_operand(tag);
+        let tag_op = bx.load_operand(tag);
+        let tag_imm = tag_op.immediate();
 
         // Decode the discriminant (specifically if it's niche-encoded).
         match *tag_encoding {
@@ -242,68 +245,161 @@ impl<'a, 'tcx, V: CodegenObject> PlaceRef<'tcx, V> {
                     Int(_, signed) => !tag_scalar.is_bool() && signed,
                     _ => false,
                 };
-                bx.intcast(tag.immediate(), cast_to, signed)
+                bx.intcast(tag_imm, cast_to, signed)
             }
             TagEncoding::Niche { untagged_variant, ref niche_variants, niche_start } => {
-                // Rebase from niche values to discriminants, and check
-                // whether the result is in range for the niche variants.
-                let niche_llty = bx.cx().immediate_backend_type(tag.layout);
-                let tag = tag.immediate();
-
-                // We first compute the "relative discriminant" (wrt `niche_variants`),
-                // that is, if `n = niche_variants.end() - niche_variants.start()`,
-                // we remap `niche_start..=niche_start + n` (which may wrap around)
-                // to (non-wrap-around) `0..=n`, to be able to check whether the
-                // discriminant corresponds to a niche variant with one comparison.
-                // We also can't go directly to the (variant index) discriminant
-                // and check that it is in the range `niche_variants`, because
-                // that might not fit in the same type, on top of needing an extra
-                // comparison (see also the comment on `let niche_discr`).
-                let relative_discr = if niche_start == 0 {
-                    // Avoid subtracting `0`, which wouldn't work for pointers.
-                    // FIXME(eddyb) check the actual primitive type here.
-                    tag
+                // Cast to an integer so we don't have to treat a pointer as a
+                // special case.
+                let (tag, tag_llty) = if tag_scalar.primitive().is_ptr() {
+                    let t = bx.type_isize();
+                    let tag = bx.ptrtoint(tag_imm, t);
+                    (tag, t)
                 } else {
-                    bx.sub(tag, bx.cx().const_uint_big(niche_llty, niche_start))
+                    (tag_imm, bx.cx().immediate_backend_type(tag_op.layout))
                 };
+
+                let tag_size = tag_scalar.size(bx.cx());
+                let max_unsigned = tag_size.unsigned_int_max();
+                let max_signed = tag_size.signed_int_max() as u128;
+                let min_signed = max_signed + 1;
                 let relative_max = niche_variants.end().as_u32() - niche_variants.start().as_u32();
-                let is_niche = if relative_max == 0 {
-                    // Avoid calling `const_uint`, which wouldn't work for pointers.
-                    // Also use canonical == 0 instead of non-canonical u<= 0.
-                    // FIXME(eddyb) check the actual primitive type here.
-                    bx.icmp(IntPredicate::IntEQ, relative_discr, bx.cx().const_null(niche_llty))
+                let niche_end = niche_start.wrapping_add(relative_max as u128) & max_unsigned;
+                let range = tag_scalar.valid_range(bx.cx());
+
+                let sle = |lhs: u128, rhs: u128| -> bool {
+                    // Signed and unsigned comparisons give the same results,
+                    // except that in signed comparisons an integer with the
+                    // sign bit set is less than one with the sign bit clear.
+                    // Toggle the sign bit to do a signed comparison.
+                    (lhs ^ min_signed) <= (rhs ^ min_signed)
+                };
+
+                // We have a subrange `niche_start..=niche_end` inside `range`.
+                // If the value of the tag is inside this subrange, it's a
+                // "niche value", an increment of the discriminant. Otherwise it
+                // indicates the untagged variant.
+                // A general algorithm to extract the discriminant from the tag
+                // is:
+                // relative_tag = tag - niche_start
+                // is_niche = relative_tag <= (ule) relative_max
+                // discr = if is_niche {
+                //     cast(relative_tag) + niche_variants.start()
+                // } else {
+                //     untagged_variant
+                // }
+                // However, we will likely be able to emit simpler code.
+
+                // Find the least and greatest values in `range`, considered
+                // both as signed and unsigned.
+                let (low_unsigned, high_unsigned) = if range.start <= range.end {
+                    (range.start, range.end)
                 } else {
-                    let relative_max = bx.cx().const_uint(niche_llty, relative_max as u64);
-                    bx.icmp(IntPredicate::IntULE, relative_discr, relative_max)
+                    (0, max_unsigned)
+                };
+                let (low_signed, high_signed) = if sle(range.start, range.end) {
+                    (range.start, range.end)
+                } else {
+                    (min_signed, max_signed)
                 };
 
-                // NOTE(eddyb) this addition needs to be performed on the final
-                // type, in case the niche itself can't represent all variant
-                // indices (e.g. `u8` niche with more than `256` variants,
-                // but enough uninhabited variants so that the remaining variants
-                // fit in the niche).
-                // In other words, `niche_variants.end - niche_variants.start`
-                // is representable in the niche, but `niche_variants.end`
-                // might not be, in extreme cases.
-                let niche_discr = {
-                    let relative_discr = if relative_max == 0 {
-                        // HACK(eddyb) since we have only one niche, we know which
-                        // one it is, and we can avoid having a dynamic value here.
-                        bx.cx().const_uint(cast_to, 0)
+                let niches_ule = niche_start <= niche_end;
+                let niches_sle = sle(niche_start, niche_end);
+                let cast_smaller = cast_to_size <= tag_size;
+
+                // In the algorithm above, we can change
+                // cast(relative_tag) + niche_variants.start()
+                // into
+                // cast(tag) + (niche_variants.start() - niche_start)
+                // if either the casted type is no larger than the original
+                // type, or if the niche values are contiguous (in either the
+                // signed or unsigned sense).
+                let can_incr_after_cast = cast_smaller || niches_ule || niches_sle;
+
+                let data_for_boundary_niche = || -> Option<(IntPredicate, u128)> {
+                    if !can_incr_after_cast {
+                        None
+                    } else if niche_start == low_unsigned {
+                        Some((IntPredicate::IntULE, niche_end))
+                    } else if niche_end == high_unsigned {
+                        Some((IntPredicate::IntUGE, niche_start))
+                    } else if niche_start == low_signed {
+                        Some((IntPredicate::IntSLE, niche_end))
+                    } else if niche_end == high_signed {
+                        Some((IntPredicate::IntSGE, niche_start))
                     } else {
-                        bx.intcast(relative_discr, cast_to, false)
-                    };
-                    bx.add(
-                        relative_discr,
-                        bx.cx().const_uint(cast_to, niche_variants.start().as_u32() as u64),
-                    )
+                        None
+                    }
                 };
 
-                bx.select(
+                let (is_niche, tagged_discr, delta) = if relative_max == 0 {
+                    // Best case scenario: only one tagged variant. This will
+                    // likely become just a comparison and a jump.
+                    // The algorithm is:
+                    // is_niche = tag == niche_start
+                    // discr = if is_niche {
+                    //     niche_start
+                    // } else {
+                    //     untagged_variant
+                    // }
+                    let niche_start = bx.cx().const_uint_big(tag_llty, niche_start);
+                    let is_niche = bx.icmp(IntPredicate::IntEQ, tag, niche_start);
+                    let tagged_discr =
+                        bx.cx().const_uint(cast_to, niche_variants.start().as_u32() as u64);
+                    (is_niche, tagged_discr, 0)
+                } else if let Some((predicate, constant)) = data_for_boundary_niche() {
+                    // The niche values are either the lowest or the highest in
+                    // `range`. We can avoid the first subtraction in the
+                    // algorithm.
+                    // The algorithm is now this:
+                    // is_niche = tag <= niche_end
+                    // discr = if is_niche {
+                    //     cast(tag) + (niche_variants.start() - niche_start)
+                    // } else {
+                    //     untagged_variant
+                    // }
+                    // (the first line may instead be tag >= niche_start,
+                    // and may be a signed or unsigned comparison)
+                    let is_niche =
+                        bx.icmp(predicate, tag, bx.cx().const_uint_big(tag_llty, constant));
+                    let cast_tag = if cast_smaller {
+                        bx.intcast(tag, cast_to, false)
+                    } else if niches_ule {
+                        bx.zext(tag, cast_to)
+                    } else {
+                        bx.sext(tag, cast_to)
+                    };
+
+                    let delta = (niche_variants.start().as_u32() as u128).wrapping_sub(niche_start);
+                    (is_niche, cast_tag, delta)
+                } else {
+                    // The special cases don't apply, so we'll have to go with
+                    // the general algorithm.
+                    let relative_discr = bx.sub(tag, bx.cx().const_uint_big(tag_llty, niche_start));
+                    let cast_tag = bx.intcast(relative_discr, cast_to, false);
+                    let is_niche = bx.icmp(
+                        IntPredicate::IntULE,
+                        relative_discr,
+                        bx.cx().const_uint(tag_llty, relative_max as u64),
+                    );
+                    (is_niche, cast_tag, niche_variants.start().as_u32() as u128)
+                };
+
+                let tagged_discr = if delta == 0 {
+                    tagged_discr
+                } else {
+                    bx.add(tagged_discr, bx.cx().const_uint_big(cast_to, delta))
+                };
+
+                let discr = bx.select(
                     is_niche,
-                    niche_discr,
+                    tagged_discr,
                     bx.cx().const_uint(cast_to, untagged_variant.as_u32() as u64),
-                )
+                );
+
+                // In principle we could insert assumes on the possible range of `discr`, but
+                // currently in LLVM this seems to be a pessimization.
+
+                discr
             }
         }
     }
diff --git a/compiler/rustc_codegen_ssa/src/target_features.rs b/compiler/rustc_codegen_ssa/src/target_features.rs
index 83407ee8f9d3..a4368303de57 100644
--- a/compiler/rustc_codegen_ssa/src/target_features.rs
+++ b/compiler/rustc_codegen_ssa/src/target_features.rs
@@ -267,6 +267,7 @@ const WASM_ALLOWED_FEATURES: &[(&str, Option<Symbol>)] = &[
     // tidy-alphabetical-start
     ("atomics", Some(sym::wasm_target_feature)),
     ("bulk-memory", Some(sym::wasm_target_feature)),
+    ("multivalue", Some(sym::wasm_target_feature)),
     ("mutable-globals", Some(sym::wasm_target_feature)),
     ("nontrapping-fptoint", Some(sym::wasm_target_feature)),
     ("reference-types", Some(sym::wasm_target_feature)),
diff --git a/compiler/rustc_codegen_ssa/src/traits/backend.rs b/compiler/rustc_codegen_ssa/src/traits/backend.rs
index 87e347c61e2b..5c35070ea66f 100644
--- a/compiler/rustc_codegen_ssa/src/traits/backend.rs
+++ b/compiler/rustc_codegen_ssa/src/traits/backend.rs
@@ -119,7 +119,7 @@ pub trait ExtraBackendMethods: CodegenBackend + WriteBackendMethods + Sized + Se
         tcx: TyCtxt<'tcx>,
         module_name: &str,
         kind: AllocatorKind,
-        has_alloc_error_handler: bool,
+        alloc_error_handler_kind: AllocatorKind,
     ) -> Self::Module;
     /// This generates the codegen unit and returns it along with
     /// a `u64` giving an estimate of the unit's processing cost.
diff --git a/compiler/rustc_codegen_ssa/src/traits/type_.rs b/compiler/rustc_codegen_ssa/src/traits/type_.rs
index 8158e8dd0112..86481d5d758d 100644
--- a/compiler/rustc_codegen_ssa/src/traits/type_.rs
+++ b/compiler/rustc_codegen_ssa/src/traits/type_.rs
@@ -5,7 +5,6 @@ use crate::common::TypeKind;
 use crate::mir::place::PlaceRef;
 use rustc_middle::ty::layout::TyAndLayout;
 use rustc_middle::ty::{self, Ty};
-use rustc_span::DUMMY_SP;
 use rustc_target::abi::call::{ArgAbi, CastTarget, FnAbi, Reg};
 use rustc_target::abi::{AddressSpace, Integer};
 
@@ -23,6 +22,7 @@ pub trait BaseTypeMethods<'tcx>: Backend<'tcx> {
     fn type_f32(&self) -> Self::Type;
     fn type_f64(&self) -> Self::Type;
 
+    fn type_array(&self, ty: Self::Type, len: u64) -> Self::Type;
     fn type_func(&self, args: &[Self::Type], ret: Self::Type) -> Self::Type;
     fn type_struct(&self, els: &[Self::Type], packed: bool) -> Self::Type;
     fn type_kind(&self, ty: Self::Type) -> TypeKind;
@@ -75,16 +75,16 @@ pub trait DerivedTypeMethods<'tcx>: BaseTypeMethods<'tcx> + MiscMethods<'tcx> {
     }
 
     fn type_is_sized(&self, ty: Ty<'tcx>) -> bool {
-        ty.is_sized(self.tcx().at(DUMMY_SP), ty::ParamEnv::reveal_all())
+        ty.is_sized(self.tcx(), ty::ParamEnv::reveal_all())
     }
 
     fn type_is_freeze(&self, ty: Ty<'tcx>) -> bool {
-        ty.is_freeze(self.tcx().at(DUMMY_SP), ty::ParamEnv::reveal_all())
+        ty.is_freeze(self.tcx(), ty::ParamEnv::reveal_all())
     }
 
     fn type_has_metadata(&self, ty: Ty<'tcx>) -> bool {
         let param_env = ty::ParamEnv::reveal_all();
-        if ty.is_sized(self.tcx().at(DUMMY_SP), param_env) {
+        if ty.is_sized(self.tcx(), param_env) {
             return false;
         }
 
diff --git a/compiler/rustc_const_eval/src/const_eval/eval_queries.rs b/compiler/rustc_const_eval/src/const_eval/eval_queries.rs
index 1b1052fdf47a..8f5e503d659d 100644
--- a/compiler/rustc_const_eval/src/const_eval/eval_queries.rs
+++ b/compiler/rustc_const_eval/src/const_eval/eval_queries.rs
@@ -46,7 +46,7 @@ fn eval_body_using_ecx<'mir, 'tcx>(
         ecx.tcx.def_kind(cid.instance.def_id())
     );
     let layout = ecx.layout_of(body.bound_return_ty().subst(tcx, cid.instance.substs))?;
-    assert!(!layout.is_unsized());
+    assert!(layout.is_sized());
     let ret = ecx.allocate(layout, MemoryKind::Stack)?;
 
     trace!(
diff --git a/compiler/rustc_const_eval/src/const_eval/fn_queries.rs b/compiler/rustc_const_eval/src/const_eval/fn_queries.rs
index cdcebb61c2e8..f1674d04f8d1 100644
--- a/compiler/rustc_const_eval/src/const_eval/fn_queries.rs
+++ b/compiler/rustc_const_eval/src/const_eval/fn_queries.rs
@@ -25,10 +25,12 @@ pub fn is_parent_const_impl_raw(tcx: TyCtxt<'_>, def_id: LocalDefId) -> bool {
 /// report whether said intrinsic has a `rustc_const_{un,}stable` attribute. Otherwise, return
 /// `Constness::NotConst`.
 fn constness(tcx: TyCtxt<'_>, def_id: DefId) -> hir::Constness {
-    let hir_id = tcx.hir().local_def_id_to_hir_id(def_id.expect_local());
-    match tcx.hir().get(hir_id) {
-        hir::Node::Ctor(_) => hir::Constness::Const,
+    let def_id = def_id.expect_local();
+    let node = tcx.hir().get_by_def_id(def_id);
 
+    match node {
+        hir::Node::Ctor(_) => hir::Constness::Const,
+        hir::Node::Item(hir::Item { kind: hir::ItemKind::Impl(impl_), .. }) => impl_.constness,
         hir::Node::ForeignItem(hir::ForeignItem { kind: hir::ForeignItemKind::Fn(..), .. }) => {
             // Intrinsics use `rustc_const_{un,}stable` attributes to indicate constness. All other
             // foreign items cannot be evaluated at compile-time.
@@ -39,62 +41,20 @@ fn constness(tcx: TyCtxt<'_>, def_id: DefId) -> hir::Constness {
             };
             if is_const { hir::Constness::Const } else { hir::Constness::NotConst }
         }
+        _ => {
+            if let Some(fn_kind) = node.fn_kind() {
+                if fn_kind.constness() == hir::Constness::Const {
+                    return hir::Constness::Const;
+                }
 
-        hir::Node::TraitItem(hir::TraitItem { kind: hir::TraitItemKind::Fn(..), .. })
-            if tcx.is_const_default_method(def_id) =>
-        {
-            hir::Constness::Const
-        }
-
-        hir::Node::Item(hir::Item { kind: hir::ItemKind::Const(..), .. })
-        | hir::Node::Item(hir::Item { kind: hir::ItemKind::Static(..), .. })
-        | hir::Node::TraitItem(hir::TraitItem { kind: hir::TraitItemKind::Const(..), .. })
-        | hir::Node::AnonConst(_)
-        | hir::Node::ImplItem(hir::ImplItem { kind: hir::ImplItemKind::Const(..), .. })
-        | hir::Node::ImplItem(hir::ImplItem {
-            kind:
-                hir::ImplItemKind::Fn(
-                    hir::FnSig {
-                        header: hir::FnHeader { constness: hir::Constness::Const, .. },
-                        ..
-                    },
-                    ..,
-                ),
-            ..
-        }) => hir::Constness::Const,
-
-        hir::Node::ImplItem(hir::ImplItem {
-            kind: hir::ImplItemKind::Type(..) | hir::ImplItemKind::Fn(..),
-            ..
-        }) => {
-            let parent_hir_id = tcx.hir().get_parent_node(hir_id);
-            match tcx.hir().get(parent_hir_id) {
-                hir::Node::Item(hir::Item {
-                    kind: hir::ItemKind::Impl(hir::Impl { constness, .. }),
-                    ..
-                }) => *constness,
-                _ => span_bug!(
-                    tcx.def_span(parent_hir_id.owner),
-                    "impl item's parent node is not an impl",
-                ),
+                // If the function itself is not annotated with `const`, it may still be a `const fn`
+                // if it resides in a const trait impl.
+                let is_const = is_parent_const_impl_raw(tcx, def_id);
+                if is_const { hir::Constness::Const } else { hir::Constness::NotConst }
+            } else {
+                hir::Constness::NotConst
             }
         }
-
-        hir::Node::Item(hir::Item {
-            kind: hir::ItemKind::Fn(hir::FnSig { header: hir::FnHeader { constness, .. }, .. }, ..),
-            ..
-        })
-        | hir::Node::TraitItem(hir::TraitItem {
-            kind:
-                hir::TraitItemKind::Fn(hir::FnSig { header: hir::FnHeader { constness, .. }, .. }, ..),
-            ..
-        })
-        | hir::Node::Item(hir::Item {
-            kind: hir::ItemKind::Impl(hir::Impl { constness, .. }),
-            ..
-        }) => *constness,
-
-        _ => hir::Constness::NotConst,
     }
 }
 
diff --git a/compiler/rustc_const_eval/src/const_eval/machine.rs b/compiler/rustc_const_eval/src/const_eval/machine.rs
index e5acacd91888..35d58d2f638b 100644
--- a/compiler/rustc_const_eval/src/const_eval/machine.rs
+++ b/compiler/rustc_const_eval/src/const_eval/machine.rs
@@ -2,10 +2,10 @@ use rustc_hir::def::DefKind;
 use rustc_middle::mir;
 use rustc_middle::ty::{self, Ty, TyCtxt};
 use std::borrow::Borrow;
-use std::collections::hash_map::Entry;
 use std::hash::Hash;
 
-use rustc_data_structures::fx::FxHashMap;
+use rustc_data_structures::fx::FxIndexMap;
+use rustc_data_structures::fx::IndexEntry;
 use std::fmt;
 
 use rustc_ast::Mutability;
@@ -107,18 +107,18 @@ impl<'mir, 'tcx> CompileTimeInterpreter<'mir, 'tcx> {
     }
 }
 
-impl<K: Hash + Eq, V> interpret::AllocMap<K, V> for FxHashMap<K, V> {
+impl<K: Hash + Eq, V> interpret::AllocMap<K, V> for FxIndexMap<K, V> {
     #[inline(always)]
     fn contains_key<Q: ?Sized + Hash + Eq>(&mut self, k: &Q) -> bool
     where
         K: Borrow<Q>,
     {
-        FxHashMap::contains_key(self, k)
+        FxIndexMap::contains_key(self, k)
     }
 
     #[inline(always)]
     fn insert(&mut self, k: K, v: V) -> Option<V> {
-        FxHashMap::insert(self, k, v)
+        FxIndexMap::insert(self, k, v)
     }
 
     #[inline(always)]
@@ -126,7 +126,7 @@ impl<K: Hash + Eq, V> interpret::AllocMap<K, V> for FxHashMap<K, V> {
     where
         K: Borrow<Q>,
     {
-        FxHashMap::remove(self, k)
+        FxIndexMap::remove(self, k)
     }
 
     #[inline(always)]
@@ -148,8 +148,8 @@ impl<K: Hash + Eq, V> interpret::AllocMap<K, V> for FxHashMap<K, V> {
     #[inline(always)]
     fn get_mut_or<E>(&mut self, k: K, vacant: impl FnOnce() -> Result<V, E>) -> Result<&mut V, E> {
         match self.entry(k) {
-            Entry::Occupied(e) => Ok(e.into_mut()),
-            Entry::Vacant(e) => {
+            IndexEntry::Occupied(e) => Ok(e.into_mut()),
+            IndexEntry::Vacant(e) => {
                 let v = vacant()?;
                 Ok(e.insert(v))
             }
diff --git a/compiler/rustc_const_eval/src/const_eval/valtrees.rs b/compiler/rustc_const_eval/src/const_eval/valtrees.rs
index a964fe8465ee..f4da11883957 100644
--- a/compiler/rustc_const_eval/src/const_eval/valtrees.rs
+++ b/compiler/rustc_const_eval/src/const_eval/valtrees.rs
@@ -212,7 +212,7 @@ fn create_pointee_place<'tcx>(
 ) -> MPlaceTy<'tcx> {
     let tcx = ecx.tcx.tcx;
 
-    if !ty.is_sized(ecx.tcx, ty::ParamEnv::empty()) {
+    if !ty.is_sized(*ecx.tcx, ty::ParamEnv::empty()) {
         // We need to create `Allocation`s for custom DSTs
 
         let (unsized_inner_ty, num_elems) = get_info_on_unsized_field(ty, valtree, tcx);
@@ -398,7 +398,7 @@ fn valtree_into_mplace<'tcx>(
 
                 let mut place_inner = match ty.kind() {
                     ty::Str | ty::Slice(_) => ecx.mplace_index(&place, i as u64).unwrap(),
-                    _ if !ty.is_sized(ecx.tcx, ty::ParamEnv::empty())
+                    _ if !ty.is_sized(*ecx.tcx, ty::ParamEnv::empty())
                         && i == branches.len() - 1 =>
                     {
                         // Note: For custom DSTs we need to manually process the last unsized field.
diff --git a/compiler/rustc_const_eval/src/interpret/cast.rs b/compiler/rustc_const_eval/src/interpret/cast.rs
index 764224fd0072..269ae15d4974 100644
--- a/compiler/rustc_const_eval/src/interpret/cast.rs
+++ b/compiler/rustc_const_eval/src/interpret/cast.rs
@@ -42,10 +42,22 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                 let res = self.pointer_from_exposed_address_cast(&src, cast_ty)?;
                 self.write_immediate(res, dest)?;
             }
-            // FIXME: We shouldn't use `misc_cast` for these but handle them separately.
-            IntToInt | FloatToInt | FloatToFloat | IntToFloat | FnPtrToPtr | PtrToPtr => {
+
+            IntToInt | IntToFloat => {
                 let src = self.read_immediate(src)?;
-                let res = self.misc_cast(&src, cast_ty)?;
+                let res = self.int_to_int_or_float(&src, cast_ty)?;
+                self.write_immediate(res, dest)?;
+            }
+
+            FloatToFloat | FloatToInt => {
+                let src = self.read_immediate(src)?;
+                let res = self.float_to_float_or_int(&src, cast_ty)?;
+                self.write_immediate(res, dest)?;
+            }
+
+            FnPtrToPtr | PtrToPtr => {
+                let src = self.read_immediate(&src)?;
+                let res = self.ptr_to_ptr(&src, cast_ty)?;
                 self.write_immediate(res, dest)?;
             }
 
@@ -126,13 +138,25 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         Ok(())
     }
 
-    pub fn misc_cast(
-        &mut self,
+    /// Handles 'IntToInt' and 'IntToFloat' casts.
+    pub fn int_to_int_or_float(
+        &self,
+        src: &ImmTy<'tcx, M::Provenance>,
+        cast_ty: Ty<'tcx>,
+    ) -> InterpResult<'tcx, Immediate<M::Provenance>> {
+        assert!(src.layout.ty.is_integral() || src.layout.ty.is_char() || src.layout.ty.is_bool());
+        assert!(cast_ty.is_floating_point() || cast_ty.is_integral() || cast_ty.is_char());
+
+        Ok(self.cast_from_int_like(src.to_scalar(), src.layout, cast_ty)?.into())
+    }
+
+    /// Handles 'FloatToFloat' and 'FloatToInt' casts.
+    pub fn float_to_float_or_int(
+        &self,
         src: &ImmTy<'tcx, M::Provenance>,
         cast_ty: Ty<'tcx>,
     ) -> InterpResult<'tcx, Immediate<M::Provenance>> {
         use rustc_type_ir::sty::TyKind::*;
-        trace!("Casting {:?}: {:?} to {:?}", *src, src.layout.ty, cast_ty);
 
         match src.layout.ty.kind() {
             // Floating point
@@ -142,47 +166,42 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
             Float(FloatTy::F64) => {
                 return Ok(self.cast_from_float(src.to_scalar().to_f64()?, cast_ty).into());
             }
-            // The rest is integer/pointer-"like", including fn ptr casts
-            _ => assert!(
-                src.layout.ty.is_bool()
-                    || src.layout.ty.is_char()
-                    || src.layout.ty.is_integral()
-                    || src.layout.ty.is_any_ptr(),
-                "Unexpected cast from type {:?}",
-                src.layout.ty
-            ),
-        }
-
-        // # First handle non-scalar source values.
-
-        // Handle casting any ptr to raw ptr (might be a fat ptr).
-        if src.layout.ty.is_any_ptr() && cast_ty.is_unsafe_ptr() {
-            let dest_layout = self.layout_of(cast_ty)?;
-            if dest_layout.size == src.layout.size {
-                // Thin or fat pointer that just hast the ptr kind of target type changed.
-                return Ok(**src);
-            } else {
-                // Casting the metadata away from a fat ptr.
-                assert_eq!(src.layout.size, 2 * self.pointer_size());
-                assert_eq!(dest_layout.size, self.pointer_size());
-                assert!(src.layout.ty.is_unsafe_ptr());
-                return match **src {
-                    Immediate::ScalarPair(data, _) => Ok(data.into()),
-                    Immediate::Scalar(..) => span_bug!(
-                        self.cur_span(),
-                        "{:?} input to a fat-to-thin cast ({:?} -> {:?})",
-                        *src,
-                        src.layout.ty,
-                        cast_ty
-                    ),
-                    Immediate::Uninit => throw_ub!(InvalidUninitBytes(None)),
-                };
+            _ => {
+                bug!("Can't cast 'Float' type into {:?}", cast_ty);
             }
         }
+    }
 
-        // # The remaining source values are scalar and "int-like".
-        let scalar = src.to_scalar();
-        Ok(self.cast_from_int_like(scalar, src.layout, cast_ty)?.into())
+    /// Handles 'FnPtrToPtr' and 'PtrToPtr' casts.
+    pub fn ptr_to_ptr(
+        &self,
+        src: &ImmTy<'tcx, M::Provenance>,
+        cast_ty: Ty<'tcx>,
+    ) -> InterpResult<'tcx, Immediate<M::Provenance>> {
+        assert!(src.layout.ty.is_any_ptr());
+        assert!(cast_ty.is_unsafe_ptr());
+        // Handle casting any ptr to raw ptr (might be a fat ptr).
+        let dest_layout = self.layout_of(cast_ty)?;
+        if dest_layout.size == src.layout.size {
+            // Thin or fat pointer that just hast the ptr kind of target type changed.
+            return Ok(**src);
+        } else {
+            // Casting the metadata away from a fat ptr.
+            assert_eq!(src.layout.size, 2 * self.pointer_size());
+            assert_eq!(dest_layout.size, self.pointer_size());
+            assert!(src.layout.ty.is_unsafe_ptr());
+            return match **src {
+                Immediate::ScalarPair(data, _) => Ok(data.into()),
+                Immediate::Scalar(..) => span_bug!(
+                    self.cur_span(),
+                    "{:?} input to a fat-to-thin cast ({:?} -> {:?})",
+                    *src,
+                    src.layout.ty,
+                    cast_ty
+                ),
+                Immediate::Uninit => throw_ub!(InvalidUninitBytes(None)),
+            };
+        }
     }
 
     pub fn pointer_expose_address_cast(
@@ -203,7 +222,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
     }
 
     pub fn pointer_from_exposed_address_cast(
-        &mut self,
+        &self,
         src: &ImmTy<'tcx, M::Provenance>,
         cast_ty: Ty<'tcx>,
     ) -> InterpResult<'tcx, Immediate<M::Provenance>> {
@@ -220,6 +239,8 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         Ok(Scalar::from_maybe_pointer(ptr, self).into())
     }
 
+    /// Low-level cast helper function. This works directly on scalars and can take 'int-like' input
+    /// type (basically everything with a scalar layout) to int/float/char types.
     pub fn cast_from_int_like(
         &self,
         scalar: Scalar<M::Provenance>, // input value (there is no ScalarTy so we separate data+layout)
@@ -259,6 +280,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         })
     }
 
+    /// Low-level cast helper function. Converts an apfloat `f` into int or float types.
     fn cast_from_float<F>(&self, f: F, dest_ty: Ty<'tcx>) -> Scalar<M::Provenance>
     where
         F: Float + Into<Scalar<M::Provenance>> + FloatConvert<Single> + FloatConvert<Double>,
diff --git a/compiler/rustc_const_eval/src/interpret/eval_context.rs b/compiler/rustc_const_eval/src/interpret/eval_context.rs
index d2e0a0dd240e..ab82268dde3a 100644
--- a/compiler/rustc_const_eval/src/interpret/eval_context.rs
+++ b/compiler/rustc_const_eval/src/interpret/eval_context.rs
@@ -468,7 +468,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
 
     #[inline]
     pub fn type_is_freeze(&self, ty: Ty<'tcx>) -> bool {
-        ty.is_freeze(self.tcx, self.param_env)
+        ty.is_freeze(*self.tcx, self.param_env)
     }
 
     pub fn load_mir(
@@ -572,7 +572,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         metadata: &MemPlaceMeta<M::Provenance>,
         layout: &TyAndLayout<'tcx>,
     ) -> InterpResult<'tcx, Option<(Size, Align)>> {
-        if !layout.is_unsized() {
+        if layout.is_sized() {
             return Ok(Some((layout.size, layout.align.abi)));
         }
         match layout.ty.kind() {
@@ -598,7 +598,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                 // the last field).  Can't have foreign types here, how would we
                 // adjust alignment and size for them?
                 let field = layout.field(self, layout.fields.count() - 1);
-                let Some((unsized_size, unsized_align)) = self.size_and_align_of(metadata, &field)? else {
+                let Some((unsized_size, mut unsized_align)) = self.size_and_align_of(metadata, &field)? else {
                     // A field with an extern type. We don't know the actual dynamic size
                     // or the alignment.
                     return Ok(None);
@@ -614,6 +614,13 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                 // Return the sum of sizes and max of aligns.
                 let size = sized_size + unsized_size; // `Size` addition
 
+                // Packed types ignore the alignment of their fields.
+                if let ty::Adt(def, _) = layout.ty.kind() {
+                    if def.repr().packed() {
+                        unsized_align = sized_align;
+                    }
+                }
+
                 // Choose max of two known alignments (combined value must
                 // be aligned according to more restrictive of the two).
                 let align = sized_align.max(unsized_align);
diff --git a/compiler/rustc_const_eval/src/interpret/intern.rs b/compiler/rustc_const_eval/src/interpret/intern.rs
index f72ae7413e30..6809a42dc453 100644
--- a/compiler/rustc_const_eval/src/interpret/intern.rs
+++ b/compiler/rustc_const_eval/src/interpret/intern.rs
@@ -15,7 +15,7 @@
 //! that contains allocations whose mutability we cannot identify.)
 
 use super::validity::RefTracking;
-use rustc_data_structures::fx::{FxHashMap, FxHashSet};
+use rustc_data_structures::fx::{FxIndexMap, FxIndexSet};
 use rustc_errors::ErrorGuaranteed;
 use rustc_hir as hir;
 use rustc_middle::mir::interpret::InterpResult;
@@ -37,7 +37,7 @@ pub trait CompileTimeMachine<'mir, 'tcx, T> = Machine<
     ExtraFnVal = !,
     FrameExtra = (),
     AllocExtra = (),
-    MemoryMap = FxHashMap<AllocId, (MemoryKind<T>, Allocation)>,
+    MemoryMap = FxIndexMap<AllocId, (MemoryKind<T>, Allocation)>,
 >;
 
 struct InternVisitor<'rt, 'mir, 'tcx, M: CompileTimeMachine<'mir, 'tcx, const_eval::MemoryKind>> {
@@ -47,7 +47,7 @@ struct InternVisitor<'rt, 'mir, 'tcx, M: CompileTimeMachine<'mir, 'tcx, const_ev
     ref_tracking: &'rt mut RefTracking<(MPlaceTy<'tcx>, InternMode)>,
     /// A list of all encountered allocations. After type-based interning, we traverse this list to
     /// also intern allocations that are only referenced by a raw pointer or inside a union.
-    leftover_allocations: &'rt mut FxHashSet<AllocId>,
+    leftover_allocations: &'rt mut FxIndexSet<AllocId>,
     /// The root kind of the value that we're looking at. This field is never mutated for a
     /// particular allocation. It is primarily used to make as many allocations as possible
     /// read-only so LLVM can place them in const memory.
@@ -79,7 +79,7 @@ struct IsStaticOrFn;
 /// to account for (e.g. for vtables).
 fn intern_shallow<'rt, 'mir, 'tcx, M: CompileTimeMachine<'mir, 'tcx, const_eval::MemoryKind>>(
     ecx: &'rt mut InterpCx<'mir, 'tcx, M>,
-    leftover_allocations: &'rt mut FxHashSet<AllocId>,
+    leftover_allocations: &'rt mut FxIndexSet<AllocId>,
     alloc_id: AllocId,
     mode: InternMode,
     ty: Option<Ty<'tcx>>,
@@ -114,7 +114,7 @@ fn intern_shallow<'rt, 'mir, 'tcx, M: CompileTimeMachine<'mir, 'tcx, const_eval:
     if let InternMode::Static(mutability) = mode {
         // For this, we need to take into account `UnsafeCell`. When `ty` is `None`, we assume
         // no interior mutability.
-        let frozen = ty.map_or(true, |ty| ty.is_freeze(ecx.tcx, ecx.param_env));
+        let frozen = ty.map_or(true, |ty| ty.is_freeze(*ecx.tcx, ecx.param_env));
         // For statics, allocation mutability is the combination of place mutability and
         // type mutability.
         // The entire allocation needs to be mutable if it contains an `UnsafeCell` anywhere.
@@ -355,7 +355,7 @@ pub fn intern_const_alloc_recursive<
     // `leftover_allocations` collects *all* allocations we see, because some might not
     // be available in a typed way. They get interned at the end.
     let mut ref_tracking = RefTracking::empty();
-    let leftover_allocations = &mut FxHashSet::default();
+    let leftover_allocations = &mut FxIndexSet::default();
 
     // start with the outermost allocation
     intern_shallow(
diff --git a/compiler/rustc_const_eval/src/interpret/intrinsics.rs b/compiler/rustc_const_eval/src/interpret/intrinsics.rs
index 8637d6a7767e..e68456a1d731 100644
--- a/compiler/rustc_const_eval/src/interpret/intrinsics.rs
+++ b/compiler/rustc_const_eval/src/interpret/intrinsics.rs
@@ -7,7 +7,9 @@ use std::convert::TryFrom;
 use rustc_hir::def_id::DefId;
 use rustc_middle::mir::{
     self,
-    interpret::{ConstValue, GlobalId, InterpResult, PointerArithmetic, Scalar},
+    interpret::{
+        Allocation, ConstAllocation, ConstValue, GlobalId, InterpResult, PointerArithmetic, Scalar,
+    },
     BinOp, NonDivergingIntrinsic,
 };
 use rustc_middle::ty;
@@ -23,7 +25,6 @@ use super::{
 };
 
 mod caller_location;
-mod type_name;
 
 fn numeric_intrinsic<Prov>(name: Symbol, bits: u128, kind: Primitive) -> Scalar<Prov> {
     let size = match kind {
@@ -42,6 +43,13 @@ fn numeric_intrinsic<Prov>(name: Symbol, bits: u128, kind: Primitive) -> Scalar<
     Scalar::from_uint(bits_out, size)
 }
 
+/// Directly returns an `Allocation` containing an absolute path representation of the given type.
+pub(crate) fn alloc_type_name<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> ConstAllocation<'tcx> {
+    let path = crate::util::type_name(tcx, ty);
+    let alloc = Allocation::from_bytes_byte_aligned_immutable(path.into_bytes());
+    tcx.intern_const_alloc(alloc)
+}
+
 /// The logic for all nullary intrinsics is implemented here. These intrinsics don't get evaluated
 /// inside an `InterpCx` and instead have their value computed directly from rustc internal info.
 pub(crate) fn eval_nullary_intrinsic<'tcx>(
@@ -55,7 +63,7 @@ pub(crate) fn eval_nullary_intrinsic<'tcx>(
     Ok(match name {
         sym::type_name => {
             ensure_monomorphic_enough(tcx, tp_ty)?;
-            let alloc = type_name::alloc_type_name(tcx, tp_ty);
+            let alloc = alloc_type_name(tcx, tp_ty);
             ConstValue::Slice { data: alloc, start: 0, end: alloc.inner().len() }
         }
         sym::needs_drop => {
@@ -705,7 +713,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         rhs: &OpTy<'tcx, <M as Machine<'mir, 'tcx>>::Provenance>,
     ) -> InterpResult<'tcx, Scalar<M::Provenance>> {
         let layout = self.layout_of(lhs.layout.ty.builtin_deref(true).unwrap().ty)?;
-        assert!(!layout.is_unsized());
+        assert!(layout.is_sized());
 
         let get_bytes = |this: &InterpCx<'mir, 'tcx, M>,
                          op: &OpTy<'tcx, <M as Machine<'mir, 'tcx>>::Provenance>,
diff --git a/compiler/rustc_const_eval/src/interpret/machine.rs b/compiler/rustc_const_eval/src/interpret/machine.rs
index 530e252b7c07..351152eba01f 100644
--- a/compiler/rustc_const_eval/src/interpret/machine.rs
+++ b/compiler/rustc_const_eval/src/interpret/machine.rs
@@ -426,7 +426,7 @@ pub macro compile_time_machine(<$mir: lifetime, $tcx: lifetime>) {
     type ExtraFnVal = !;
 
     type MemoryMap =
-        rustc_data_structures::fx::FxHashMap<AllocId, (MemoryKind<Self::MemoryKind>, Allocation)>;
+        rustc_data_structures::fx::FxIndexMap<AllocId, (MemoryKind<Self::MemoryKind>, Allocation)>;
     const GLOBAL_KIND: Option<Self::MemoryKind> = None; // no copying of globals from `tcx` to machine memory
 
     type AllocExtra = ();
diff --git a/compiler/rustc_const_eval/src/interpret/memory.rs b/compiler/rustc_const_eval/src/interpret/memory.rs
index e5e015c1e180..a529972db9d6 100644
--- a/compiler/rustc_const_eval/src/interpret/memory.rs
+++ b/compiler/rustc_const_eval/src/interpret/memory.rs
@@ -683,7 +683,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                 // Use size and align of the type.
                 let ty = self.tcx.type_of(def_id);
                 let layout = self.tcx.layout_of(ParamEnv::empty().and(ty)).unwrap();
-                assert!(!layout.is_unsized());
+                assert!(layout.is_sized());
                 (layout.size, layout.align.abi, AllocKind::LiveData)
             }
             Some(GlobalAlloc::Memory(alloc)) => {
diff --git a/compiler/rustc_const_eval/src/interpret/operand.rs b/compiler/rustc_const_eval/src/interpret/operand.rs
index 719588a936ce..f0a83b7a0268 100644
--- a/compiler/rustc_const_eval/src/interpret/operand.rs
+++ b/compiler/rustc_const_eval/src/interpret/operand.rs
@@ -4,7 +4,7 @@
 use rustc_hir::def::Namespace;
 use rustc_middle::ty::layout::{LayoutOf, PrimitiveExt, TyAndLayout};
 use rustc_middle::ty::print::{FmtPrinter, PrettyPrinter};
-use rustc_middle::ty::{ConstInt, DelaySpanBugEmitted, Ty};
+use rustc_middle::ty::{ConstInt, Ty};
 use rustc_middle::{mir, ty};
 use rustc_target::abi::{self, Abi, Align, HasDataLayout, Size, TagEncoding};
 use rustc_target::abi::{VariantIdx, Variants};
@@ -280,7 +280,7 @@ impl<'tcx, Prov: Provenance> OpTy<'tcx, Prov> {
         layout: TyAndLayout<'tcx>,
         cx: &impl HasDataLayout,
     ) -> InterpResult<'tcx, Self> {
-        assert!(!layout.is_unsized());
+        assert!(layout.is_sized());
         self.offset_with_meta(offset, MemPlaceMeta::None, layout, cx)
     }
 }
@@ -376,7 +376,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
 
     /// Read an immediate from a place, asserting that that is possible with the given layout.
     ///
-    /// If this suceeds, the `ImmTy` is never `Uninit`.
+    /// If this succeeds, the `ImmTy` is never `Uninit`.
     #[inline(always)]
     pub fn read_immediate(
         &self,
@@ -554,13 +554,20 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         val: &mir::ConstantKind<'tcx>,
         layout: Option<TyAndLayout<'tcx>>,
     ) -> InterpResult<'tcx, OpTy<'tcx, M::Provenance>> {
+        // FIXME(const_prop): normalization needed b/c const prop lint in
+        // `mir_drops_elaborated_and_const_checked`, which happens before
+        // optimized MIR. Only after optimizing the MIR can we guarantee
+        // that the `RevealAll` pass has happened and that the body's consts
+        // are normalized, so any call to resolve before that needs to be
+        // manually normalized.
+        let val = self.tcx.normalize_erasing_regions(self.param_env, *val);
         match val {
             mir::ConstantKind::Ty(ct) => {
                 match ct.kind() {
                     ty::ConstKind::Param(_) | ty::ConstKind::Placeholder(..) => {
                         throw_inval!(TooGeneric)
                     }
-                    ty::ConstKind::Error(DelaySpanBugEmitted { reported, .. }) => {
+                    ty::ConstKind::Error(reported) => {
                         throw_inval!(AlreadyReported(reported))
                     }
                     ty::ConstKind::Unevaluated(uv) => {
@@ -585,7 +592,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                     }
                 }
             }
-            mir::ConstantKind::Val(val, ty) => self.const_val_to_op(*val, *ty, layout),
+            mir::ConstantKind::Val(val, ty) => self.const_val_to_op(val, ty, layout),
             mir::ConstantKind::Unevaluated(uv, _) => {
                 let instance = self.resolve(uv.def, uv.substs)?;
                 Ok(self.eval_to_allocation(GlobalId { instance, promoted: uv.promoted })?.into())
diff --git a/compiler/rustc_const_eval/src/interpret/place.rs b/compiler/rustc_const_eval/src/interpret/place.rs
index b0625b5f412e..29d2312612ea 100644
--- a/compiler/rustc_const_eval/src/interpret/place.rs
+++ b/compiler/rustc_const_eval/src/interpret/place.rs
@@ -201,7 +201,7 @@ impl<'tcx, Prov: Provenance> MPlaceTy<'tcx, Prov> {
         layout: TyAndLayout<'tcx>,
         cx: &impl HasDataLayout,
     ) -> InterpResult<'tcx, Self> {
-        assert!(!layout.is_unsized());
+        assert!(layout.is_sized());
         self.offset_with_meta(offset, MemPlaceMeta::None, layout, cx)
     }
 
@@ -316,8 +316,7 @@ where
         Ok(MPlaceTy { mplace, layout, align })
     }
 
-    /// Take an operand, representing a pointer, and dereference it to a place -- that
-    /// will always be a MemPlace.  Lives in `place.rs` because it creates a place.
+    /// Take an operand, representing a pointer, and dereference it to a place.
     #[instrument(skip(self), level = "debug")]
     pub fn deref_operand(
         &self,
@@ -331,7 +330,7 @@ where
         }
 
         let mplace = self.ref_to_mplace(&val)?;
-        self.check_mplace_access(mplace, CheckInAllocMsg::DerefTest)?;
+        self.check_mplace(mplace)?;
         Ok(mplace)
     }
 
@@ -340,7 +339,7 @@ where
         &self,
         place: &MPlaceTy<'tcx, M::Provenance>,
     ) -> InterpResult<'tcx, Option<AllocRef<'_, 'tcx, M::Provenance, M::AllocExtra>>> {
-        assert!(!place.layout.is_unsized());
+        assert!(place.layout.is_sized());
         assert!(!place.meta.has_meta());
         let size = place.layout.size;
         self.get_ptr_alloc(place.ptr, size, place.align)
@@ -351,24 +350,25 @@ where
         &mut self,
         place: &MPlaceTy<'tcx, M::Provenance>,
     ) -> InterpResult<'tcx, Option<AllocRefMut<'_, 'tcx, M::Provenance, M::AllocExtra>>> {
-        assert!(!place.layout.is_unsized());
+        assert!(place.layout.is_sized());
         assert!(!place.meta.has_meta());
         let size = place.layout.size;
         self.get_ptr_alloc_mut(place.ptr, size, place.align)
     }
 
     /// Check if this mplace is dereferenceable and sufficiently aligned.
-    fn check_mplace_access(
-        &self,
-        mplace: MPlaceTy<'tcx, M::Provenance>,
-        msg: CheckInAllocMsg,
-    ) -> InterpResult<'tcx> {
+    pub fn check_mplace(&self, mplace: MPlaceTy<'tcx, M::Provenance>) -> InterpResult<'tcx> {
         let (size, align) = self
             .size_and_align_of_mplace(&mplace)?
             .unwrap_or((mplace.layout.size, mplace.layout.align.abi));
         assert!(mplace.align <= align, "dynamic alignment less strict than static one?");
         let align = M::enforce_alignment(self).then_some(align);
-        self.check_ptr_access_align(mplace.ptr, size, align.unwrap_or(Align::ONE), msg)?;
+        self.check_ptr_access_align(
+            mplace.ptr,
+            size,
+            align.unwrap_or(Align::ONE),
+            CheckInAllocMsg::DerefTest,
+        )?;
         Ok(())
     }
 
@@ -485,7 +485,7 @@ where
         src: Immediate<M::Provenance>,
         dest: &PlaceTy<'tcx, M::Provenance>,
     ) -> InterpResult<'tcx> {
-        assert!(!dest.layout.is_unsized(), "Cannot write unsized data");
+        assert!(dest.layout.is_sized(), "Cannot write unsized data");
         trace!("write_immediate: {:?} <- {:?}: {}", *dest, src, dest.layout.ty);
 
         // See if we can avoid an allocation. This is the counterpart to `read_immediate_raw`,
@@ -746,7 +746,7 @@ where
         layout: TyAndLayout<'tcx>,
         kind: MemoryKind<M::MemoryKind>,
     ) -> InterpResult<'tcx, MPlaceTy<'tcx, M::Provenance>> {
-        assert!(!layout.is_unsized());
+        assert!(layout.is_sized());
         let ptr = self.allocate_ptr(layout.size, layout.align.abi, kind)?;
         Ok(MPlaceTy::from_aligned_ptr(ptr.into(), layout))
     }
diff --git a/compiler/rustc_const_eval/src/interpret/step.rs b/compiler/rustc_const_eval/src/interpret/step.rs
index c6e04cbfb6bf..3c286fa61bec 100644
--- a/compiler/rustc_const_eval/src/interpret/step.rs
+++ b/compiler/rustc_const_eval/src/interpret/step.rs
@@ -209,7 +209,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
 
             Repeat(ref operand, _) => {
                 let src = self.eval_operand(operand, None)?;
-                assert!(!src.layout.is_unsized());
+                assert!(src.layout.is_sized());
                 let dest = self.force_allocation(&dest)?;
                 let length = dest.len(self)?;
 
diff --git a/compiler/rustc_const_eval/src/interpret/traits.rs b/compiler/rustc_const_eval/src/interpret/traits.rs
index cab23b7241ff..fa15d466ac12 100644
--- a/compiler/rustc_const_eval/src/interpret/traits.rs
+++ b/compiler/rustc_const_eval/src/interpret/traits.rs
@@ -53,7 +53,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
     ) -> InterpResult<'tcx, (Size, Align)> {
         let (ty, _trait_ref) = self.get_ptr_vtable(vtable)?;
         let layout = self.layout_of(ty)?;
-        assert!(!layout.is_unsized(), "there are no vtables for unsized types");
+        assert!(layout.is_sized(), "there are no vtables for unsized types");
         Ok((layout.size, layout.align.abi))
     }
 }
diff --git a/compiler/rustc_const_eval/src/interpret/validity.rs b/compiler/rustc_const_eval/src/interpret/validity.rs
index d4146c242410..8aa56c275d91 100644
--- a/compiler/rustc_const_eval/src/interpret/validity.rs
+++ b/compiler/rustc_const_eval/src/interpret/validity.rs
@@ -15,7 +15,6 @@ use rustc_middle::mir::interpret::InterpError;
 use rustc_middle::ty;
 use rustc_middle::ty::layout::{LayoutOf, TyAndLayout};
 use rustc_span::symbol::{sym, Symbol};
-use rustc_span::DUMMY_SP;
 use rustc_target::abi::{Abi, Scalar as ScalarAbi, Size, VariantIdx, Variants, WrappingRange};
 
 use std::hash::Hash;
@@ -726,7 +725,7 @@ impl<'rt, 'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> ValueVisitor<'mir, 'tcx, M>
     ) -> InterpResult<'tcx> {
         // Special check preventing `UnsafeCell` inside unions in the inner part of constants.
         if matches!(self.ctfe_mode, Some(CtfeValidationMode::Const { inner: true, .. })) {
-            if !op.layout.ty.is_freeze(self.ecx.tcx.at(DUMMY_SP), self.ecx.param_env) {
+            if !op.layout.ty.is_freeze(*self.ecx.tcx, self.ecx.param_env) {
                 throw_validation_failure!(self.path, { "`UnsafeCell` in a `const`" });
             }
         }
diff --git a/compiler/rustc_const_eval/src/lib.rs b/compiler/rustc_const_eval/src/lib.rs
index 230f841cf4d5..443c01fdb90c 100644
--- a/compiler/rustc_const_eval/src/lib.rs
+++ b/compiler/rustc_const_eval/src/lib.rs
@@ -22,7 +22,6 @@ Rust MIR: a lowered representation of Rust.
 #![feature(yeet_expr)]
 #![feature(is_some_and)]
 #![recursion_limit = "256"]
-#![allow(rustc::potential_query_instability)]
 
 #[macro_use]
 extern crate tracing;
diff --git a/compiler/rustc_const_eval/src/transform/check_consts/check.rs b/compiler/rustc_const_eval/src/transform/check_consts/check.rs
index 22a61774e8cf..5a8b3e30b9fc 100644
--- a/compiler/rustc_const_eval/src/transform/check_consts/check.rs
+++ b/compiler/rustc_const_eval/src/transform/check_consts/check.rs
@@ -13,11 +13,8 @@ use rustc_middle::ty::{self, adjustment::PointerCast, Instance, InstanceDef, Ty,
 use rustc_middle::ty::{Binder, TraitPredicate, TraitRef, TypeVisitable};
 use rustc_mir_dataflow::{self, Analysis};
 use rustc_span::{sym, Span, Symbol};
-use rustc_trait_selection::infer::InferCtxtExt;
 use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt as _;
-use rustc_trait_selection::traits::{
-    self, ObligationCauseCode, SelectionContext, TraitEngine, TraitEngineExt,
-};
+use rustc_trait_selection::traits::{self, ObligationCauseCode, ObligationCtxt, SelectionContext};
 
 use std::mem;
 use std::ops::Deref;
@@ -747,37 +744,28 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> {
                     // "non-const" check. This is required for correctness here.
                     {
                         let infcx = tcx.infer_ctxt().build();
-                        let mut fulfill_cx = <dyn TraitEngine<'_>>::new(infcx.tcx);
+                        let ocx = ObligationCtxt::new(&infcx);
+
                         let predicates = tcx.predicates_of(callee).instantiate(tcx, substs);
                         let hir_id = tcx
                             .hir()
                             .local_def_id_to_hir_id(self.body.source.def_id().expect_local());
-                        let cause = || {
-                            ObligationCause::new(
-                                terminator.source_info.span,
-                                hir_id,
-                                ObligationCauseCode::ItemObligation(callee),
-                            )
-                        };
-                        let normalized = infcx.partially_normalize_associated_types_in(
-                            cause(),
-                            param_env,
-                            predicates,
+                        let cause = ObligationCause::new(
+                            terminator.source_info.span,
+                            hir_id,
+                            ObligationCauseCode::ItemObligation(callee),
                         );
-
-                        for p in normalized.obligations {
-                            fulfill_cx.register_predicate_obligation(&infcx, p);
-                        }
-                        for obligation in traits::predicates_for_generics(
-                            |_, _| cause(),
+                        let normalized_predicates =
+                            ocx.normalize(cause.clone(), param_env, predicates);
+                        ocx.register_obligations(traits::predicates_for_generics(
+                            |_, _| cause.clone(),
                             self.param_env,
-                            normalized.value,
-                        ) {
-                            fulfill_cx.register_predicate_obligation(&infcx, obligation);
-                        }
-                        let errors = fulfill_cx.select_all_or_error(&infcx);
+                            normalized_predicates,
+                        ));
+
+                        let errors = ocx.select_all_or_error();
                         if !errors.is_empty() {
-                            infcx.err_ctxt().report_fulfillment_errors(&errors, None, false);
+                            infcx.err_ctxt().report_fulfillment_errors(&errors, None);
                         }
                     }
 
@@ -843,7 +831,6 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> {
                                         obligation.clone(),
                                         &obligation,
                                         &e,
-                                        false,
                                     );
                                 }
 
diff --git a/compiler/rustc_const_eval/src/transform/check_consts/qualifs.rs b/compiler/rustc_const_eval/src/transform/check_consts/qualifs.rs
index b77b213b51a5..d995d533ca3e 100644
--- a/compiler/rustc_const_eval/src/transform/check_consts/qualifs.rs
+++ b/compiler/rustc_const_eval/src/transform/check_consts/qualifs.rs
@@ -8,7 +8,6 @@ use rustc_infer::infer::TyCtxtInferExt;
 use rustc_middle::mir;
 use rustc_middle::mir::*;
 use rustc_middle::ty::{self, subst::SubstsRef, AdtDef, Ty};
-use rustc_span::DUMMY_SP;
 use rustc_trait_selection::traits::{
     self, ImplSource, Obligation, ObligationCause, SelectionContext,
 };
@@ -92,7 +91,7 @@ impl Qualif for HasMutInterior {
     }
 
     fn in_any_value_of_ty<'tcx>(cx: &ConstCx<'_, 'tcx>, ty: Ty<'tcx>) -> bool {
-        !ty.is_freeze(cx.tcx.at(DUMMY_SP), cx.param_env)
+        !ty.is_freeze(cx.tcx, cx.param_env)
     }
 
     fn in_adt_inherently<'tcx>(
@@ -147,6 +146,7 @@ impl Qualif for NeedsNonConstDrop {
         qualifs.needs_non_const_drop
     }
 
+    #[instrument(level = "trace", skip(cx), ret)]
     fn in_any_value_of_ty<'tcx>(cx: &ConstCx<'_, 'tcx>, ty: Ty<'tcx>) -> bool {
         // Avoid selecting for simple cases, such as builtin types.
         if ty::util::is_trivially_const_drop(ty) {
@@ -175,6 +175,8 @@ impl Qualif for NeedsNonConstDrop {
             return true;
         };
 
+        trace!(?impl_src);
+
         if !matches!(
             impl_src,
             ImplSource::ConstDestruct(_) | ImplSource::Param(_, ty::BoundConstness::ConstIfConst)
diff --git a/compiler/rustc_const_eval/src/transform/check_consts/resolver.rs b/compiler/rustc_const_eval/src/transform/check_consts/resolver.rs
index 60c1e4950292..805e6096b35c 100644
--- a/compiler/rustc_const_eval/src/transform/check_consts/resolver.rs
+++ b/compiler/rustc_const_eval/src/transform/check_consts/resolver.rs
@@ -8,7 +8,6 @@ use rustc_middle::mir::{self, BasicBlock, Local, Location, Statement, StatementK
 use rustc_mir_dataflow::fmt::DebugWithContext;
 use rustc_mir_dataflow::JoinSemiLattice;
 use rustc_mir_dataflow::{Analysis, AnalysisDomain, CallReturnPlaces};
-use rustc_span::DUMMY_SP;
 
 use std::fmt;
 use std::marker::PhantomData;
@@ -120,10 +119,7 @@ where
     ///
     /// [rust-lang/unsafe-code-guidelines#134]: https://github.com/rust-lang/unsafe-code-guidelines/issues/134
     fn shared_borrow_allows_mutation(&self, place: mir::Place<'tcx>) -> bool {
-        !place
-            .ty(self.ccx.body, self.ccx.tcx)
-            .ty
-            .is_freeze(self.ccx.tcx.at(DUMMY_SP), self.ccx.param_env)
+        !place.ty(self.ccx.body, self.ccx.tcx).ty.is_freeze(self.ccx.tcx, self.ccx.param_env)
     }
 }
 
diff --git a/compiler/rustc_const_eval/src/transform/promote_consts.rs b/compiler/rustc_const_eval/src/transform/promote_consts.rs
index 4b219300739c..f48bcd908096 100644
--- a/compiler/rustc_const_eval/src/transform/promote_consts.rs
+++ b/compiler/rustc_const_eval/src/transform/promote_consts.rs
@@ -41,19 +41,14 @@ pub struct PromoteTemps<'tcx> {
 }
 
 impl<'tcx> MirPass<'tcx> for PromoteTemps<'tcx> {
-    fn phase_change(&self) -> Option<MirPhase> {
-        Some(MirPhase::Analysis(AnalysisPhase::Initial))
-    }
-
     fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
         // There's not really any point in promoting errorful MIR.
         //
         // This does not include MIR that failed const-checking, which we still try to promote.
-        if body.return_ty().references_error() {
-            tcx.sess.delay_span_bug(body.span, "PromoteTemps: MIR had errors");
+        if let Err(_) = body.return_ty().error_reported() {
+            debug!("PromoteTemps: MIR had errors");
             return;
         }
-
         if body.source.promoted.is_some() {
             return;
         }
diff --git a/compiler/rustc_const_eval/src/transform/validate.rs b/compiler/rustc_const_eval/src/transform/validate.rs
index fbb129f97247..81b82a21fa1a 100644
--- a/compiler/rustc_const_eval/src/transform/validate.rs
+++ b/compiler/rustc_const_eval/src/transform/validate.rs
@@ -235,9 +235,8 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> {
             // `Operand::Copy` is only supposed to be used with `Copy` types.
             if let Operand::Copy(place) = operand {
                 let ty = place.ty(&self.body.local_decls, self.tcx).ty;
-                let span = self.body.source_info(location).span;
 
-                if !ty.is_copy_modulo_regions(self.tcx.at(span), self.param_env) {
+                if !ty.is_copy_modulo_regions(self.tcx, self.param_env) {
                     self.fail(location, format!("`Operand::Copy` with non-`Copy` type {}", ty));
                 }
             }
@@ -556,21 +555,36 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> {
                 check_kinds!(a, "Cannot shallow init type {:?}", ty::RawPtr(..));
             }
             Rvalue::Cast(kind, operand, target_type) => {
+                let op_ty = operand.ty(self.body, self.tcx);
                 match kind {
                     CastKind::DynStar => {
                         // FIXME(dyn-star): make sure nothing needs to be done here.
                     }
-                    // Nothing to check here
+                    // FIXME: Add Checks for these
                     CastKind::PointerFromExposedAddress
                     | CastKind::PointerExposeAddress
                     | CastKind::Pointer(_) => {}
-                    _ => {
-                        let op_ty = operand.ty(self.body, self.tcx);
-                        if op_ty.is_enum() {
+                    CastKind::IntToInt | CastKind::IntToFloat => {
+                        let input_valid = op_ty.is_integral() || op_ty.is_char() || op_ty.is_bool();
+                        let target_valid = target_type.is_numeric() || target_type.is_char();
+                        if !input_valid || !target_valid {
+                            self.fail(
+                                location,
+                                format!("Wrong cast kind {kind:?} for the type {op_ty}",),
+                            );
+                        }
+                    }
+                    CastKind::FnPtrToPtr | CastKind::PtrToPtr => {
+                        if !(op_ty.is_any_ptr() && target_type.is_unsafe_ptr()) {
+                            self.fail(location, "Can't cast {op_ty} into 'Ptr'");
+                        }
+                    }
+                    CastKind::FloatToFloat | CastKind::FloatToInt => {
+                        if !op_ty.is_floating_point() || !target_type.is_numeric() {
                             self.fail(
                                 location,
                                 format!(
-                                    "enum -> int casts should go through `Rvalue::Discriminant`: {operand:?}:{op_ty} as {target_type}",
+                                    "Trying to cast non 'Float' as {kind:?} into {target_type:?}"
                                 ),
                             );
                         }
diff --git a/compiler/rustc_const_eval/src/util/call_kind.rs b/compiler/rustc_const_eval/src/util/call_kind.rs
index af9d83f0609e..5446ccb1a473 100644
--- a/compiler/rustc_const_eval/src/util/call_kind.rs
+++ b/compiler/rustc_const_eval/src/util/call_kind.rs
@@ -3,7 +3,7 @@
 //! context.
 
 use rustc_hir::def_id::DefId;
-use rustc_hir::lang_items::LangItemGroup;
+use rustc_hir::lang_items;
 use rustc_middle::ty::subst::SubstsRef;
 use rustc_middle::ty::{self, AssocItemContainer, DefIdTree, Instance, ParamEnv, Ty, TyCtxt};
 use rustc_span::symbol::Ident;
@@ -74,22 +74,24 @@ pub fn call_kind<'tcx>(
         }
     });
 
-    let fn_call = parent
-        .and_then(|p| tcx.lang_items().group(LangItemGroup::Fn).iter().find(|did| **did == p));
+    let fn_call = parent.and_then(|p| {
+        lang_items::FN_TRAITS.iter().filter_map(|&l| tcx.lang_items().get(l)).find(|&id| id == p)
+    });
 
-    let operator = (!from_hir_call)
-        .then(|| parent)
-        .flatten()
-        .and_then(|p| tcx.lang_items().group(LangItemGroup::Op).iter().find(|did| **did == p));
+    let operator = if !from_hir_call && let Some(p) = parent {
+        lang_items::OPERATORS.iter().filter_map(|&l| tcx.lang_items().get(l)).find(|&id| id == p)
+    } else {
+        None
+    };
 
     let is_deref = !from_hir_call && tcx.is_diagnostic_item(sym::deref_method, method_did);
 
     // Check for a 'special' use of 'self' -
     // an FnOnce call, an operator (e.g. `<<`), or a
     // deref coercion.
-    let kind = if let Some(&trait_id) = fn_call {
+    let kind = if let Some(trait_id) = fn_call {
         Some(CallKind::FnCall { fn_trait_id: trait_id, self_ty: method_substs.type_at(0) })
-    } else if let Some(&trait_id) = operator {
+    } else if let Some(trait_id) = operator {
         Some(CallKind::Operator { self_arg, trait_id, self_ty: method_substs.type_at(0) })
     } else if is_deref {
         let deref_target = tcx.get_diagnostic_item(sym::deref_target).and_then(|deref_target| {
diff --git a/compiler/rustc_const_eval/src/util/mod.rs b/compiler/rustc_const_eval/src/util/mod.rs
index 7a05cfd235fa..4d0f81a40600 100644
--- a/compiler/rustc_const_eval/src/util/mod.rs
+++ b/compiler/rustc_const_eval/src/util/mod.rs
@@ -4,9 +4,11 @@ mod call_kind;
 pub mod collect_writes;
 mod find_self_call;
 mod might_permit_raw_init;
+mod type_name;
 
 pub use self::aggregate::expand_aggregate;
 pub use self::alignment::is_disaligned;
 pub use self::call_kind::{call_kind, CallDesugaringKind, CallKind};
 pub use self::find_self_call::find_self_call;
 pub use self::might_permit_raw_init::might_permit_raw_init;
+pub use self::type_name::type_name;
diff --git a/compiler/rustc_const_eval/src/interpret/intrinsics/type_name.rs b/compiler/rustc_const_eval/src/util/type_name.rs
similarity index 88%
rename from compiler/rustc_const_eval/src/interpret/intrinsics/type_name.rs
rename to compiler/rustc_const_eval/src/util/type_name.rs
index 7e4c5fcb031b..08a6d69b8e40 100644
--- a/compiler/rustc_const_eval/src/interpret/intrinsics/type_name.rs
+++ b/compiler/rustc_const_eval/src/util/type_name.rs
@@ -1,7 +1,6 @@
 use rustc_data_structures::intern::Interned;
 use rustc_hir::def_id::CrateNum;
 use rustc_hir::definitions::DisambiguatedDefPathData;
-use rustc_middle::mir::interpret::{Allocation, ConstAllocation};
 use rustc_middle::ty::{
     self,
     print::{PrettyPrinter, Print, Printer},
@@ -74,18 +73,10 @@ impl<'tcx> Printer<'tcx> for AbsolutePathPrinter<'tcx> {
     }
 
     fn print_dyn_existential(
-        mut self,
+        self,
         predicates: &'tcx ty::List<ty::Binder<'tcx, ty::ExistentialPredicate<'tcx>>>,
     ) -> Result<Self::DynExistential, Self::Error> {
-        let mut first = true;
-        for p in predicates {
-            if !first {
-                write!(self, "+")?;
-            }
-            first = false;
-            self = p.print(self)?;
-        }
-        Ok(self)
+        self.pretty_print_dyn_existential(predicates)
     }
 
     fn path_crate(mut self, cnum: CrateNum) -> Result<Self::Path, Self::Error> {
@@ -179,6 +170,11 @@ impl<'tcx> PrettyPrinter<'tcx> for AbsolutePathPrinter<'tcx> {
 
         Ok(self)
     }
+
+    fn should_print_verbose(&self) -> bool {
+        // `std::any::type_name` should never print verbose type names
+        false
+    }
 }
 
 impl Write for AbsolutePathPrinter<'_> {
@@ -188,9 +184,6 @@ impl Write for AbsolutePathPrinter<'_> {
     }
 }
 
-/// Directly returns an `Allocation` containing an absolute path representation of the given type.
-pub(crate) fn alloc_type_name<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> ConstAllocation<'tcx> {
-    let path = AbsolutePathPrinter { tcx, path: String::new() }.print_type(ty).unwrap().path;
-    let alloc = Allocation::from_bytes_byte_aligned_immutable(path.into_bytes());
-    tcx.intern_const_alloc(alloc)
+pub fn type_name<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> String {
+    AbsolutePathPrinter { tcx, path: String::new() }.print_type(ty).unwrap().path
 }
diff --git a/compiler/rustc_data_structures/Cargo.toml b/compiler/rustc_data_structures/Cargo.toml
index 9daa21ef6b11..5afce15e26bf 100644
--- a/compiler/rustc_data_structures/Cargo.toml
+++ b/compiler/rustc_data_structures/Cargo.toml
@@ -23,9 +23,9 @@ rustc_macros = { path = "../rustc_macros" }
 rustc_serialize = { path = "../rustc_serialize" }
 smallvec = { version = "1.8.1", features = ["const_generics", "union", "may_dangle"] }
 stable_deref_trait = "1.0.0"
-stacker = "0.1.14"
+stacker = "0.1.15"
 tempfile = "3.2"
-thin-vec = "0.2.8"
+thin-vec = "0.2.9"
 tracing = "0.1"
 
 [dependencies.parking_lot]
diff --git a/compiler/rustc_data_structures/src/intern.rs b/compiler/rustc_data_structures/src/intern.rs
index 009b5d5340af..11cbff8ea6a8 100644
--- a/compiler/rustc_data_structures/src/intern.rs
+++ b/compiler/rustc_data_structures/src/intern.rs
@@ -110,11 +110,6 @@ where
     }
 }
 
-/// A helper trait so that `Interned` things can cache stable hashes reproducibly.
-pub trait InternedHashingContext {
-    fn with_def_path_and_no_spans(&mut self, f: impl FnOnce(&mut Self));
-}
-
 /// A helper type that you can wrap round your own type in order to automatically
 /// cache the stable hash on creation and not recompute it whenever the stable hash
 /// of the type is computed.
@@ -161,11 +156,15 @@ impl<T> Deref for WithStableHash<T> {
 impl<T: Hash> Hash for WithStableHash<T> {
     #[inline]
     fn hash<H: Hasher>(&self, s: &mut H) {
-        self.internee.hash(s)
+        if self.stable_hash != Fingerprint::ZERO {
+            self.stable_hash.hash(s)
+        } else {
+            self.internee.hash(s)
+        }
     }
 }
 
-impl<T: HashStable<CTX>, CTX: InternedHashingContext> HashStable<CTX> for WithStableHash<T> {
+impl<T: HashStable<CTX>, CTX> HashStable<CTX> for WithStableHash<T> {
     fn hash_stable(&self, hcx: &mut CTX, hasher: &mut StableHasher) {
         if self.stable_hash == Fingerprint::ZERO || cfg!(debug_assertions) {
             // No cached hash available. This can only mean that incremental is disabled.
@@ -176,7 +175,7 @@ impl<T: HashStable<CTX>, CTX: InternedHashingContext> HashStable<CTX> for WithSt
             // otherwise the hashes will differ between cached and non-cached mode.
             let stable_hash: Fingerprint = {
                 let mut hasher = StableHasher::new();
-                hcx.with_def_path_and_no_spans(|hcx| self.internee.hash_stable(hcx, &mut hasher));
+                self.internee.hash_stable(hcx, &mut hasher);
                 hasher.finish()
             };
             if cfg!(debug_assertions) && self.stable_hash != Fingerprint::ZERO {
diff --git a/compiler/rustc_data_structures/src/lib.rs b/compiler/rustc_data_structures/src/lib.rs
index 467ac401d086..3a2000233c5d 100644
--- a/compiler/rustc_data_structures/src/lib.rs
+++ b/compiler/rustc_data_structures/src/lib.rs
@@ -22,6 +22,7 @@
 #![feature(new_uninit)]
 #![feature(once_cell)]
 #![feature(rustc_attrs)]
+#![feature(negative_impls)]
 #![feature(test)]
 #![feature(thread_id_value)]
 #![feature(vec_into_raw_parts)]
@@ -86,6 +87,7 @@ pub mod steal;
 pub mod tagged_ptr;
 pub mod temp_dir;
 pub mod unhash;
+pub mod unord;
 
 pub use ena::undo_log;
 pub use ena::unify;
diff --git a/compiler/rustc_data_structures/src/sync.rs b/compiler/rustc_data_structures/src/sync.rs
index 9c0fb8265cff..c550f246e094 100644
--- a/compiler/rustc_data_structures/src/sync.rs
+++ b/compiler/rustc_data_structures/src/sync.rs
@@ -410,6 +410,7 @@ impl<T> Lock<T> {
 
     #[cfg(parallel_compiler)]
     #[inline(always)]
+    #[track_caller]
     pub fn lock(&self) -> LockGuard<'_, T> {
         if ERROR_CHECKING {
             self.0.try_lock().expect("lock was already held")
@@ -420,21 +421,25 @@ impl<T> Lock<T> {
 
     #[cfg(not(parallel_compiler))]
     #[inline(always)]
+    #[track_caller]
     pub fn lock(&self) -> LockGuard<'_, T> {
         self.0.borrow_mut()
     }
 
     #[inline(always)]
+    #[track_caller]
     pub fn with_lock<F: FnOnce(&mut T) -> R, R>(&self, f: F) -> R {
         f(&mut *self.lock())
     }
 
     #[inline(always)]
+    #[track_caller]
     pub fn borrow(&self) -> LockGuard<'_, T> {
         self.lock()
     }
 
     #[inline(always)]
+    #[track_caller]
     pub fn borrow_mut(&self) -> LockGuard<'_, T> {
         self.lock()
     }
@@ -476,6 +481,7 @@ impl<T> RwLock<T> {
 
     #[cfg(not(parallel_compiler))]
     #[inline(always)]
+    #[track_caller]
     pub fn read(&self) -> ReadGuard<'_, T> {
         self.0.borrow()
     }
@@ -491,6 +497,7 @@ impl<T> RwLock<T> {
     }
 
     #[inline(always)]
+    #[track_caller]
     pub fn with_read_lock<F: FnOnce(&T) -> R, R>(&self, f: F) -> R {
         f(&*self.read())
     }
@@ -509,6 +516,7 @@ impl<T> RwLock<T> {
 
     #[cfg(not(parallel_compiler))]
     #[inline(always)]
+    #[track_caller]
     pub fn write(&self) -> WriteGuard<'_, T> {
         self.0.borrow_mut()
     }
@@ -524,16 +532,19 @@ impl<T> RwLock<T> {
     }
 
     #[inline(always)]
+    #[track_caller]
     pub fn with_write_lock<F: FnOnce(&mut T) -> R, R>(&self, f: F) -> R {
         f(&mut *self.write())
     }
 
     #[inline(always)]
+    #[track_caller]
     pub fn borrow(&self) -> ReadGuard<'_, T> {
         self.read()
     }
 
     #[inline(always)]
+    #[track_caller]
     pub fn borrow_mut(&self) -> WriteGuard<'_, T> {
         self.write()
     }
diff --git a/compiler/rustc_data_structures/src/unord.rs b/compiler/rustc_data_structures/src/unord.rs
new file mode 100644
index 000000000000..c015f1232cd9
--- /dev/null
+++ b/compiler/rustc_data_structures/src/unord.rs
@@ -0,0 +1,382 @@
+//! This module contains collection types that don't expose their internal
+//! ordering. This is a useful property for deterministic computations, such
+//! as required by the query system.
+
+use rustc_hash::{FxHashMap, FxHashSet};
+use smallvec::SmallVec;
+use std::{
+    borrow::Borrow,
+    hash::Hash,
+    iter::{Product, Sum},
+};
+
+use crate::{
+    fingerprint::Fingerprint,
+    stable_hasher::{HashStable, StableHasher, ToStableHashKey},
+};
+
+/// `UnordItems` is the order-less version of `Iterator`. It only contains methods
+/// that don't (easily) expose an ordering of the underlying items.
+///
+/// Most methods take an `Fn` where the `Iterator`-version takes an `FnMut`. This
+/// is to reduce the risk of accidentally leaking the internal order via the closure
+/// environment. Otherwise one could easily do something like
+///
+/// ```rust,ignore (pseudo code)
+/// let mut ordered = vec![];
+/// unordered_items.all(|x| ordered.push(x));
+/// ```
+///
+/// It's still possible to do the same thing with an `Fn` by using interior mutability,
+/// but the chance of doing it accidentally is reduced.
+pub struct UnordItems<T, I: Iterator<Item = T>>(I);
+
+impl<T, I: Iterator<Item = T>> UnordItems<T, I> {
+    #[inline]
+    pub fn map<U, F: Fn(T) -> U>(self, f: F) -> UnordItems<U, impl Iterator<Item = U>> {
+        UnordItems(self.0.map(f))
+    }
+
+    #[inline]
+    pub fn all<U, F: Fn(T) -> bool>(mut self, f: F) -> bool {
+        self.0.all(f)
+    }
+
+    #[inline]
+    pub fn any<U, F: Fn(T) -> bool>(mut self, f: F) -> bool {
+        self.0.any(f)
+    }
+
+    #[inline]
+    pub fn filter<U, F: Fn(&T) -> bool>(self, f: F) -> UnordItems<T, impl Iterator<Item = T>> {
+        UnordItems(self.0.filter(f))
+    }
+
+    #[inline]
+    pub fn filter_map<U, F: Fn(T) -> Option<U>>(
+        self,
+        f: F,
+    ) -> UnordItems<U, impl Iterator<Item = U>> {
+        UnordItems(self.0.filter_map(f))
+    }
+
+    #[inline]
+    pub fn max(self) -> Option<T>
+    where
+        T: Ord,
+    {
+        self.0.max()
+    }
+
+    #[inline]
+    pub fn min(self) -> Option<T>
+    where
+        T: Ord,
+    {
+        self.0.min()
+    }
+
+    #[inline]
+    pub fn sum<S>(self) -> S
+    where
+        S: Sum<T>,
+    {
+        self.0.sum()
+    }
+
+    #[inline]
+    pub fn product<S>(self) -> S
+    where
+        S: Product<T>,
+    {
+        self.0.product()
+    }
+
+    #[inline]
+    pub fn count(self) -> usize {
+        self.0.count()
+    }
+}
+
+impl<'a, T: Clone + 'a, I: Iterator<Item = &'a T>> UnordItems<&'a T, I> {
+    #[inline]
+    pub fn cloned(self) -> UnordItems<T, impl Iterator<Item = T>> {
+        UnordItems(self.0.cloned())
+    }
+}
+
+impl<'a, T: Copy + 'a, I: Iterator<Item = &'a T>> UnordItems<&'a T, I> {
+    #[inline]
+    pub fn copied(self) -> UnordItems<T, impl Iterator<Item = T>> {
+        UnordItems(self.0.copied())
+    }
+}
+
+impl<T: Ord, I: Iterator<Item = T>> UnordItems<T, I> {
+    pub fn into_sorted<HCX>(self, hcx: &HCX) -> Vec<T>
+    where
+        T: ToStableHashKey<HCX>,
+    {
+        let mut items: Vec<T> = self.0.collect();
+        items.sort_by_cached_key(|x| x.to_stable_hash_key(hcx));
+        items
+    }
+
+    pub fn into_sorted_small_vec<HCX, const LEN: usize>(self, hcx: &HCX) -> SmallVec<[T; LEN]>
+    where
+        T: ToStableHashKey<HCX>,
+    {
+        let mut items: SmallVec<[T; LEN]> = self.0.collect();
+        items.sort_by_cached_key(|x| x.to_stable_hash_key(hcx));
+        items
+    }
+}
+
+/// This is a set collection type that tries very hard to not expose
+/// any internal iteration. This is a useful property when trying to
+/// uphold the determinism invariants imposed by the query system.
+///
+/// This collection type is a good choice for set-like collections the
+/// keys of which don't have a semantic ordering.
+///
+/// See [MCP 533](https://github.com/rust-lang/compiler-team/issues/533)
+/// for more information.
+#[derive(Debug, Eq, PartialEq, Clone, Encodable, Decodable)]
+pub struct UnordSet<V: Eq + Hash> {
+    inner: FxHashSet<V>,
+}
+
+impl<V: Eq + Hash> Default for UnordSet<V> {
+    fn default() -> Self {
+        Self { inner: FxHashSet::default() }
+    }
+}
+
+impl<V: Eq + Hash> UnordSet<V> {
+    #[inline]
+    pub fn new() -> Self {
+        Self { inner: Default::default() }
+    }
+
+    #[inline]
+    pub fn len(&self) -> usize {
+        self.inner.len()
+    }
+
+    #[inline]
+    pub fn insert(&mut self, v: V) -> bool {
+        self.inner.insert(v)
+    }
+
+    #[inline]
+    pub fn contains<Q: ?Sized>(&self, v: &Q) -> bool
+    where
+        V: Borrow<Q>,
+        Q: Hash + Eq,
+    {
+        self.inner.contains(v)
+    }
+
+    #[inline]
+    pub fn items<'a>(&'a self) -> UnordItems<&'a V, impl Iterator<Item = &'a V>> {
+        UnordItems(self.inner.iter())
+    }
+
+    #[inline]
+    pub fn into_items(self) -> UnordItems<V, impl Iterator<Item = V>> {
+        UnordItems(self.inner.into_iter())
+    }
+
+    // We can safely extend this UnordSet from a set of unordered values because that
+    // won't expose the internal ordering anywhere.
+    #[inline]
+    pub fn extend<I: Iterator<Item = V>>(&mut self, items: UnordItems<V, I>) {
+        self.inner.extend(items.0)
+    }
+}
+
+impl<V: Hash + Eq> Extend<V> for UnordSet<V> {
+    fn extend<T: IntoIterator<Item = V>>(&mut self, iter: T) {
+        self.inner.extend(iter)
+    }
+}
+
+impl<HCX, V: Hash + Eq + HashStable<HCX>> HashStable<HCX> for UnordSet<V> {
+    #[inline]
+    fn hash_stable(&self, hcx: &mut HCX, hasher: &mut StableHasher) {
+        hash_iter_order_independent(self.inner.iter(), hcx, hasher);
+    }
+}
+
+/// This is a map collection type that tries very hard to not expose
+/// any internal iteration. This is a useful property when trying to
+/// uphold the determinism invariants imposed by the query system.
+///
+/// This collection type is a good choice for map-like collections the
+/// keys of which don't have a semantic ordering.
+///
+/// See [MCP 533](https://github.com/rust-lang/compiler-team/issues/533)
+/// for more information.
+#[derive(Debug, Eq, PartialEq, Clone, Encodable, Decodable)]
+pub struct UnordMap<K: Eq + Hash, V> {
+    inner: FxHashMap<K, V>,
+}
+
+impl<K: Eq + Hash, V> Default for UnordMap<K, V> {
+    fn default() -> Self {
+        Self { inner: FxHashMap::default() }
+    }
+}
+
+impl<K: Hash + Eq, V> Extend<(K, V)> for UnordMap<K, V> {
+    fn extend<T: IntoIterator<Item = (K, V)>>(&mut self, iter: T) {
+        self.inner.extend(iter)
+    }
+}
+
+impl<K: Eq + Hash, V> UnordMap<K, V> {
+    #[inline]
+    pub fn len(&self) -> usize {
+        self.inner.len()
+    }
+
+    #[inline]
+    pub fn insert(&mut self, k: K, v: V) -> Option<V> {
+        self.inner.insert(k, v)
+    }
+
+    #[inline]
+    pub fn contains_key<Q: ?Sized>(&self, k: &Q) -> bool
+    where
+        K: Borrow<Q>,
+        Q: Hash + Eq,
+    {
+        self.inner.contains_key(k)
+    }
+
+    #[inline]
+    pub fn items<'a>(&'a self) -> UnordItems<(&'a K, &'a V), impl Iterator<Item = (&'a K, &'a V)>> {
+        UnordItems(self.inner.iter())
+    }
+
+    #[inline]
+    pub fn into_items(self) -> UnordItems<(K, V), impl Iterator<Item = (K, V)>> {
+        UnordItems(self.inner.into_iter())
+    }
+
+    // We can safely extend this UnordMap from a set of unordered values because that
+    // won't expose the internal ordering anywhere.
+    #[inline]
+    pub fn extend<I: Iterator<Item = (K, V)>>(&mut self, items: UnordItems<(K, V), I>) {
+        self.inner.extend(items.0)
+    }
+}
+
+impl<HCX, K: Hash + Eq + HashStable<HCX>, V: HashStable<HCX>> HashStable<HCX> for UnordMap<K, V> {
+    #[inline]
+    fn hash_stable(&self, hcx: &mut HCX, hasher: &mut StableHasher) {
+        hash_iter_order_independent(self.inner.iter(), hcx, hasher);
+    }
+}
+
+/// This is a collection type that tries very hard to not expose
+/// any internal iteration. This is a useful property when trying to
+/// uphold the determinism invariants imposed by the query system.
+///
+/// This collection type is a good choice for collections the
+/// keys of which don't have a semantic ordering and don't implement
+/// `Hash` or `Eq`.
+///
+/// See [MCP 533](https://github.com/rust-lang/compiler-team/issues/533)
+/// for more information.
+#[derive(Default, Debug, Eq, PartialEq, Clone, Encodable, Decodable)]
+pub struct UnordBag<V> {
+    inner: Vec<V>,
+}
+
+impl<V> UnordBag<V> {
+    #[inline]
+    pub fn new() -> Self {
+        Self { inner: Default::default() }
+    }
+
+    #[inline]
+    pub fn len(&self) -> usize {
+        self.inner.len()
+    }
+
+    #[inline]
+    pub fn push(&mut self, v: V) {
+        self.inner.push(v);
+    }
+
+    #[inline]
+    pub fn items<'a>(&'a self) -> UnordItems<&'a V, impl Iterator<Item = &'a V>> {
+        UnordItems(self.inner.iter())
+    }
+
+    #[inline]
+    pub fn into_items(self) -> UnordItems<V, impl Iterator<Item = V>> {
+        UnordItems(self.inner.into_iter())
+    }
+
+    // We can safely extend this UnordSet from a set of unordered values because that
+    // won't expose the internal ordering anywhere.
+    #[inline]
+    pub fn extend<I: Iterator<Item = V>>(&mut self, items: UnordItems<V, I>) {
+        self.inner.extend(items.0)
+    }
+}
+
+impl<T> Extend<T> for UnordBag<T> {
+    fn extend<I: IntoIterator<Item = T>>(&mut self, iter: I) {
+        self.inner.extend(iter)
+    }
+}
+
+impl<HCX, V: Hash + Eq + HashStable<HCX>> HashStable<HCX> for UnordBag<V> {
+    #[inline]
+    fn hash_stable(&self, hcx: &mut HCX, hasher: &mut StableHasher) {
+        hash_iter_order_independent(self.inner.iter(), hcx, hasher);
+    }
+}
+
+fn hash_iter_order_independent<
+    HCX,
+    T: HashStable<HCX>,
+    I: Iterator<Item = T> + ExactSizeIterator,
+>(
+    mut it: I,
+    hcx: &mut HCX,
+    hasher: &mut StableHasher,
+) {
+    let len = it.len();
+    len.hash_stable(hcx, hasher);
+
+    match len {
+        0 => {
+            // We're done
+        }
+        1 => {
+            // No need to instantiate a hasher
+            it.next().unwrap().hash_stable(hcx, hasher);
+        }
+        _ => {
+            let mut accumulator = Fingerprint::ZERO;
+            for item in it {
+                let mut item_hasher = StableHasher::new();
+                item.hash_stable(hcx, &mut item_hasher);
+                let item_fingerprint: Fingerprint = item_hasher.finish();
+                accumulator = accumulator.combine_commutative(item_fingerprint);
+            }
+            accumulator.hash_stable(hcx, hasher);
+        }
+    }
+}
+
+// Do not implement IntoIterator for the collections in this module.
+// They only exist to hide iteration order in the first place.
+impl<T> !IntoIterator for UnordBag<T> {}
+impl<V> !IntoIterator for UnordSet<V> {}
+impl<K, V> !IntoIterator for UnordMap<K, V> {}
+impl<T, I> !IntoIterator for UnordItems<T, I> {}
diff --git a/compiler/rustc_driver/src/lib.rs b/compiler/rustc_driver/src/lib.rs
index 7edbb6f757ce..e043368fdfe0 100644
--- a/compiler/rustc_driver/src/lib.rs
+++ b/compiler/rustc_driver/src/lib.rs
@@ -6,6 +6,7 @@
 
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
 #![feature(once_cell)]
+#![feature(decl_macro)]
 #![recursion_limit = "256"]
 #![allow(rustc::potential_query_instability)]
 #![deny(rustc::untranslatable_diagnostic)]
@@ -427,18 +428,6 @@ fn run_compiler(
     })
 }
 
-#[cfg(unix)]
-pub fn set_sigpipe_handler() {
-    unsafe {
-        // Set the SIGPIPE signal handler, so that an EPIPE
-        // will cause rustc to terminate, as expected.
-        assert_ne!(libc::signal(libc::SIGPIPE, libc::SIG_DFL), libc::SIG_ERR);
-    }
-}
-
-#[cfg(windows)]
-pub fn set_sigpipe_handler() {}
-
 // Extract output directory and file from matches.
 fn make_output(matches: &getopts::Matches) -> (Option<PathBuf>, Option<PathBuf>) {
     let odir = matches.opt_str("out-dir").map(|o| PathBuf::from(&o));
@@ -748,26 +737,58 @@ fn print_crate_info(
             // Any output here interferes with Cargo's parsing of other printed output
             NativeStaticLibs => {}
             LinkArgs => {}
+            SplitDebuginfo => {
+                use rustc_target::spec::SplitDebuginfo::{Off, Packed, Unpacked};
+
+                for split in &[Off, Packed, Unpacked] {
+                    let stable = sess.target.options.supported_split_debuginfo.contains(split);
+                    let unstable_ok = sess.unstable_options();
+                    if stable || unstable_ok {
+                        println!("{}", split);
+                    }
+                }
+            }
         }
     }
     Compilation::Stop
 }
 
 /// Prints version information
-pub fn version(binary: &str, matches: &getopts::Matches) {
+///
+/// NOTE: this is a macro to support drivers built at a different time than the main `rustc_driver` crate.
+pub macro version($binary: literal, $matches: expr) {
+    fn unw(x: Option<&str>) -> &str {
+        x.unwrap_or("unknown")
+    }
+    $crate::version_at_macro_invocation(
+        $binary,
+        $matches,
+        unw(option_env!("CFG_VERSION")),
+        unw(option_env!("CFG_VER_HASH")),
+        unw(option_env!("CFG_VER_DATE")),
+        unw(option_env!("CFG_RELEASE")),
+    )
+}
+
+#[doc(hidden)] // use the macro instead
+pub fn version_at_macro_invocation(
+    binary: &str,
+    matches: &getopts::Matches,
+    version: &str,
+    commit_hash: &str,
+    commit_date: &str,
+    release: &str,
+) {
     let verbose = matches.opt_present("verbose");
 
-    println!("{} {}", binary, util::version_str().unwrap_or("unknown version"));
+    println!("{} {}", binary, version);
 
     if verbose {
-        fn unw(x: Option<&str>) -> &str {
-            x.unwrap_or("unknown")
-        }
         println!("binary: {}", binary);
-        println!("commit-hash: {}", unw(util::commit_hash_str()));
-        println!("commit-date: {}", unw(util::commit_date_str()));
+        println!("commit-hash: {}", commit_hash);
+        println!("commit-date: {}", commit_date);
         println!("host: {}", config::host_triple());
-        println!("release: {}", unw(util::release_str()));
+        println!("release: {}", release);
 
         let debug_flags = matches.opt_strs("Z");
         let backend_name = debug_flags.iter().find_map(|x| x.strip_prefix("codegen-backend="));
@@ -1083,7 +1104,7 @@ pub fn handle_options(args: &[String]) -> Option<getopts::Matches> {
     }
 
     if matches.opt_present("version") {
-        version("rustc", &matches);
+        version!("rustc", &matches);
         return None;
     }
 
@@ -1212,6 +1233,7 @@ pub fn report_ice(info: &panic::PanicInfo<'_>, bug_report_url: &str) {
         false,
         None,
         false,
+        false,
     ));
     let handler = rustc_errors::Handler::with_emitter(true, None, emitter);
 
@@ -1227,7 +1249,7 @@ pub fn report_ice(info: &panic::PanicInfo<'_>, bug_report_url: &str) {
         format!("we would appreciate a bug report: {}", bug_report_url).into(),
         format!(
             "rustc {} running on {}",
-            util::version_str().unwrap_or("unknown_version"),
+            util::version_str!().unwrap_or("unknown_version"),
             config::host_triple()
         )
         .into(),
diff --git a/compiler/rustc_error_codes/src/error_codes/E0207.md b/compiler/rustc_error_codes/src/error_codes/E0207.md
index 8a7923ac93f9..95e7c9fc76ce 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0207.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0207.md
@@ -1,4 +1,5 @@
-A type parameter that is specified for `impl` is not constrained.
+A type, const or lifetime parameter that is specified for `impl` is not
+constrained.
 
 Erroneous code example:
 
@@ -14,8 +15,8 @@ impl<T: Default> Foo {
 }
 ```
 
-Any type parameter of an `impl` must meet at least one of
-the following criteria:
+Any type or const parameter of an `impl` must meet at least one of the
+following criteria:
 
  - it appears in the _implementing type_ of the impl, e.g. `impl<T> Foo<T>`
  - for a trait impl, it appears in the _implemented trait_, e.g.
@@ -23,6 +24,9 @@ the following criteria:
  - it is bound as an associated type, e.g. `impl<T, U> SomeTrait for T
    where T: AnotherTrait<AssocType=U>`
 
+Any unconstrained lifetime parameter of an `impl` is not supported if the
+lifetime parameter is used by an associated type.
+
 ### Error example 1
 
 Suppose we have a struct `Foo` and we would like to define some methods for it.
@@ -32,7 +36,6 @@ The problem is that the parameter `T` does not appear in the implementing type
 (`Foo`) of the impl. In this case, we can fix the error by moving the type
 parameter from the `impl` to the method `get`:
 
-
 ```
 struct Foo;
 
@@ -128,6 +131,70 @@ impl<T: Default> Maker<Foo<T>> for FooMaker {
 }
 ```
 
+### Error example 3
+
+Suppose we have a struct `Foo` and we would like to define some methods for it.
+The following code example has a definition which leads to a compiler error:
+
+```compile_fail,E0207
+struct Foo;
+
+impl<const T: i32> Foo {
+    // error: the const parameter `T` is not constrained by the impl trait, self
+    // type, or predicates [E0207]
+    fn get(&self) -> i32 {
+        i32::default()
+    }
+}
+```
+
+The problem is that the const parameter `T` does not appear in the implementing
+type (`Foo`) of the impl. In this case, we can fix the error by moving the type
+parameter from the `impl` to the method `get`:
+
+
+```
+struct Foo;
+
+// Move the const parameter from the impl to the method
+impl Foo {
+    fn get<const T: i32>(&self) -> i32 {
+        i32::default()
+    }
+}
+```
+
+### Error example 4
+
+Suppose we have a struct `Foo` and a struct `Bar` that uses lifetime `'a`. We
+would like to implement trait `Contains` for `Foo`. The trait `Contains` have
+the associated type `B`. The following code example has a definition which
+leads to a compiler error:
+
+```compile_fail,E0207
+struct Foo;
+struct Bar<'a>;
+
+trait Contains {
+    type B;
+
+    fn get(&self) -> i32;
+}
+
+impl<'a> Contains for Foo {
+    type B = Bar<'a>;
+
+    // error: the lifetime parameter `'a` is not constrained by the impl trait,
+    // self type, or predicates [E0207]
+    fn get(&self) -> i32 {
+        i32::default()
+    }
+}
+```
+
+Please note that unconstrained lifetime parameters are not supported if they are
+being used by an associated type.
+
 ### Additional information
 
 For more information, please see [RFC 447].
diff --git a/compiler/rustc_error_codes/src/error_codes/E0210.md b/compiler/rustc_error_codes/src/error_codes/E0210.md
index dc2fd9b0ca04..41263e5e3f5a 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0210.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0210.md
@@ -76,7 +76,5 @@ Let `Ti` be the first such type.
 For information on the design of the orphan rules,
 see [RFC 2451] and [RFC 1023].
 
-For information on the design of the orphan rules, see [RFC 1023].
-
 [RFC 2451]: https://rust-lang.github.io/rfcs/2451-re-rebalancing-coherence.html
 [RFC 1023]: https://github.com/rust-lang/rfcs/blob/master/text/1023-rebalancing-coherence.md
diff --git a/compiler/rustc_error_codes/src/error_codes/E0322.md b/compiler/rustc_error_codes/src/error_codes/E0322.md
index ccef8681dd60..194bbd83b0f7 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0322.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0322.md
@@ -1,4 +1,5 @@
-The `Sized` trait was implemented explicitly.
+A built-in trait was implemented explicitly. All implementations of the trait
+are provided automatically by the compiler.
 
 Erroneous code example:
 
diff --git a/compiler/rustc_error_codes/src/error_codes/E0382.md b/compiler/rustc_error_codes/src/error_codes/E0382.md
index d1408a062963..cbc4980f8cab 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0382.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0382.md
@@ -61,7 +61,7 @@ with `#[derive(Clone)]`.
 
 Some types have no ownership semantics at all and are trivial to duplicate. An
 example is `i32` and the other number types. We don't have to call `.clone()` to
-clone them, because they are marked `Copy` in addition to `Clone`.  Implicit
+clone them, because they are marked `Copy` in addition to `Clone`. Implicit
 cloning is more convenient in this case. We can mark our own types `Copy` if
 all their members also are marked `Copy`.
 
diff --git a/compiler/rustc_error_codes/src/error_codes/E0706.md b/compiler/rustc_error_codes/src/error_codes/E0706.md
index d379b8a2384c..fabd855a222f 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0706.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0706.md
@@ -56,4 +56,4 @@ You might be interested in visiting the [async book] for further information.
 [`async-trait` crate]: https://crates.io/crates/async-trait
 [async-is-hard]: https://smallcultfollowing.com/babysteps/blog/2019/10/26/async-fn-in-traits-are-hard/
 [Generic Associated Types]: https://github.com/rust-lang/rust/issues/44265
-[async book]: https://rust-lang.github.io/async-book/07_workarounds/06_async_in_traits.html
+[async book]: https://rust-lang.github.io/async-book/07_workarounds/05_async_in_traits.html
diff --git a/compiler/rustc_error_codes/src/error_codes/E0732.md b/compiler/rustc_error_codes/src/error_codes/E0732.md
index 7347e6654c5b..9536fdbf0df8 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0732.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0732.md
@@ -3,8 +3,6 @@ An `enum` with a discriminant must specify a `#[repr(inttype)]`.
 Erroneous code example:
 
 ```compile_fail,E0732
-#![feature(arbitrary_enum_discriminant)]
-
 enum Enum { // error!
     Unit = 1,
     Tuple() = 2,
@@ -20,8 +18,6 @@ is a well-defined way to extract a variant's discriminant from a value;
 for instance:
 
 ```
-#![feature(arbitrary_enum_discriminant)]
-
 #[repr(u8)]
 enum Enum {
     Unit = 3,
diff --git a/compiler/rustc_error_messages/locales/en-US/borrowck.ftl b/compiler/rustc_error_messages/locales/en-US/borrowck.ftl
index 67f2156f32e5..de47ada82644 100644
--- a/compiler/rustc_error_messages/locales/en-US/borrowck.ftl
+++ b/compiler/rustc_error_messages/locales/en-US/borrowck.ftl
@@ -58,3 +58,68 @@ borrowck_returned_lifetime_short =
 
 borrowck_used_impl_require_static =
     the used `impl` has a `'static` requirement
+
+borrowck_capture_kind_label =
+    capture is {$kind_desc} because of use here
+
+borrowck_var_borrow_by_use_place_in_generator =
+    borrow occurs due to use of {$place} in closure in generator
+
+borrowck_var_borrow_by_use_place_in_closure =
+    borrow occurs due to use of {$place} in closure
+
+borrowck_var_borrow_by_use_place =
+    borrow occurs due to use of {$place}
+
+borrowck_borrow_due_to_use_generator =
+    borrow occurs due to use in generator
+
+borrowck_use_due_to_use_generator =
+    use occurs due to use in generator
+
+borrowck_assign_due_to_use_generator =
+    assign occurs due to use in generator
+
+borrowck_assign_part_due_to_use_generator =
+    assign to part occurs due to use in generator
+
+borrowck_borrow_due_to_use_closure =
+    borrow occurs due to use in closure
+
+borrowck_use_due_to_use_closure =
+    use occurs due to use in closure
+
+borrowck_assign_due_to_use_closure =
+    assign occurs due to use in closure
+
+borrowck_assign_part_due_to_use_closure =
+    assign to part occurs due to use in closure
+
+borrowck_capture_immute =
+    capture is immutable because of use here
+
+borrowck_capture_mut =
+    capture is mutable because of use here
+
+borrowck_capture_move =
+    capture is moved because of use here
+
+borrowck_var_move_by_use_place_in_generator =
+    move occurs due to use of {$place} in generator
+
+borrowck_var_move_by_use_place_in_closure =
+    move occurs due to use of {$place} in closure
+
+borrowck_cannot_move_when_borrowed =
+    cannot move out of {$place ->
+        [value] value
+        *[other] {$place}
+    } because it is borrowed
+    .label = borrow of {$borrow_place ->
+        [value] value
+        *[other] {$borrow_place}
+    } occurs here
+    .move_label = move out of {$value_place ->
+        [value] value
+        *[other] {$value_place}
+    } occurs here
diff --git a/compiler/rustc_error_messages/locales/en-US/codegen_llvm.ftl b/compiler/rustc_error_messages/locales/en-US/codegen_llvm.ftl
new file mode 100644
index 000000000000..68a205df6c7a
--- /dev/null
+++ b/compiler/rustc_error_messages/locales/en-US/codegen_llvm.ftl
@@ -0,0 +1,58 @@
+codegen_llvm_unknown_ctarget_feature =
+    unknown feature specified for `-Ctarget-feature`: `{$feature}`
+    .note = it is still passed through to the codegen backend
+    .possible_feature = you might have meant: `{$rust_feature}`
+    .consider_filing_feature_request = consider filing a feature request
+
+codegen_llvm_unknown_ctarget_feature_prefix =
+    unknown feature specified for `-Ctarget-feature`: `{$feature}`
+    .note = features must begin with a `+` to enable or `-` to disable it
+
+codegen_llvm_error_creating_import_library =
+    Error creating import library for {$lib_name}: {$error}
+
+codegen_llvm_instrument_coverage_requires_llvm_12 =
+    rustc option `-C instrument-coverage` requires LLVM 12 or higher.
+
+codegen_llvm_symbol_already_defined =
+    symbol `{$symbol_name}` is already defined
+
+codegen_llvm_branch_protection_requires_aarch64 =
+    -Zbranch-protection is only supported on aarch64
+
+codegen_llvm_invalid_minimum_alignment =
+    invalid minimum global alignment: {$err}
+
+codegen_llvm_linkage_const_or_mut_type =
+    must have type `*const T` or `*mut T` due to `#[linkage]` attribute
+
+codegen_llvm_sanitizer_memtag_requires_mte =
+    `-Zsanitizer=memtag` requires `-Ctarget-feature=+mte`
+
+codegen_llvm_archive_build_failure =
+    failed to build archive: {$error}
+
+codegen_llvm_error_writing_def_file =
+    Error writing .DEF file: {$error}
+
+codegen_llvm_error_calling_dlltool =
+    Error calling dlltool: {$error}
+
+codegen_llvm_dlltool_fail_import_library =
+    Dlltool could not create import library: {$stdout}\n{$stderr}
+
+codegen_llvm_unknown_archive_kind =
+    Don't know how to build archive of type: {$kind}
+
+codegen_llvm_target_feature_disable_or_enable =
+    the target features {$features} must all be either enabled or disabled together
+
+codegen_llvm_missing_features =
+    add the missing features in a `target_feature` attribute
+
+codegen_llvm_dynamic_linking_with_lto =
+    cannot prefer dynamic linking when performing LTO
+    .note = only 'staticlib', 'bin', and 'cdylib' outputs are supported with LTO
+
+codegen_llvm_fail_parsing_target_machine_config_to_target_machine =
+    failed to parse target machine config to target machine: {$error}
diff --git a/compiler/rustc_error_messages/locales/en-US/codegen_ssa.ftl b/compiler/rustc_error_messages/locales/en-US/codegen_ssa.ftl
index 966a421bcf08..eb6b403d00e8 100644
--- a/compiler/rustc_error_messages/locales/en-US/codegen_ssa.ftl
+++ b/compiler/rustc_error_messages/locales/en-US/codegen_ssa.ftl
@@ -119,3 +119,68 @@ codegen_ssa_thorin_object_read = {$error}
 codegen_ssa_thorin_object_write = {$error}
 codegen_ssa_thorin_gimli_read = {$error}
 codegen_ssa_thorin_gimli_write = {$error}
+
+codegen_ssa_link_exe_unexpected_error = `link.exe` returned an unexpected error
+
+codegen_ssa_repair_vs_build_tools = the Visual Studio build tools may need to be repaired using the Visual Studio installer
+
+codegen_ssa_missing_cpp_build_tool_component = or a necessary component may be missing from the "C++ build tools" workload
+
+codegen_ssa_select_cpp_build_tool_workload = in the Visual Studio installer, ensure the "C++ build tools" workload is selected
+
+codegen_ssa_visual_studio_not_installed = you may need to install Visual Studio build tools with the "C++ build tools" workload
+
+codegen_ssa_linker_not_found = linker `{$linker_path}` not found
+    .note = {$error}
+
+codegen_ssa_unable_to_exe_linker = could not exec the linker `{$linker_path}`
+    .note = {$error}
+    .command_note = {$command_formatted}
+
+codegen_ssa_msvc_missing_linker = the msvc targets depend on the msvc linker but `link.exe` was not found
+
+codegen_ssa_check_installed_visual_studio = please ensure that Visual Studio 2017 or later, or Build Tools for Visual Studio were installed with the Visual C++ option.
+
+codegen_ssa_unsufficient_vs_code_product = VS Code is a different product, and is not sufficient.
+
+codegen_ssa_processing_dymutil_failed = processing debug info with `dsymutil` failed: {$status}
+    .note = {$output}
+
+codegen_ssa_unable_to_run_dsymutil = unable to run `dsymutil`: {$error}
+
+codegen_ssa_stripping_debu_info_failed = stripping debug info with `{$util}` failed: {$status}
+    .note = {$output}
+
+codegen_ssa_unable_to_run = unable to run `{$util}`: {$error}
+
+codegen_ssa_linker_file_stem = couldn't extract file stem from specified linker
+
+codegen_ssa_static_library_native_artifacts = Link against the following native artifacts when linking against this static library. The order and any duplication can be significant on some platforms.
+
+codegen_ssa_native_static_libs = native-static-libs: {$arguments}
+
+codegen_ssa_link_script_unavailable = can only use link script when linking with GNU-like linker
+
+codegen_ssa_link_script_write_failure = failed to write link script to {$path}: {$error}
+
+codegen_ssa_failed_to_write = failed to write {$path}: {$error}
+
+codegen_ssa_unable_to_write_debugger_visualizer = Unable to write debugger visualizer file `{$path}`: {$error}
+
+codegen_ssa_rlib_archive_build_failure = failed to build archive from rlib: {$error}
+
+codegen_ssa_option_gcc_only = option `-Z gcc-ld` is used even though linker flavor is not gcc
+
+codegen_ssa_extract_bundled_libs_open_file = failed to open file '{$rlib}': {$error}
+codegen_ssa_extract_bundled_libs_mmap_file = failed to mmap file '{$rlib}': {$error}
+codegen_ssa_extract_bundled_libs_parse_archive = failed to parse archive '{$rlib}': {$error}
+codegen_ssa_extract_bundled_libs_read_entry = failed to read entry '{$rlib}': {$error}
+codegen_ssa_extract_bundled_libs_archive_member = failed to get data from archive member '{$rlib}': {$error}
+codegen_ssa_extract_bundled_libs_convert_name = failed to convert name '{$rlib}': {$error}
+codegen_ssa_extract_bundled_libs_write_file = failed to write file '{$rlib}': {$error}
+
+codegen_ssa_unsupported_arch = unsupported arch `{$arch}` for os `{$os}`
+
+codegen_ssa_apple_sdk_error_sdk_path = failed to get {$sdk_name} SDK path: {error}
+
+codegen_ssa_read_file = failed to read file: {message}
diff --git a/compiler/rustc_error_messages/locales/en-US/hir_analysis.ftl b/compiler/rustc_error_messages/locales/en-US/hir_analysis.ftl
index 357c6900a70e..d27edd47470e 100644
--- a/compiler/rustc_error_messages/locales/en-US/hir_analysis.ftl
+++ b/compiler/rustc_error_messages/locales/en-US/hir_analysis.ftl
@@ -93,7 +93,7 @@ hir_analysis_expected_default_return_type = expected `()` because of default ret
 hir_analysis_expected_return_type = expected `{$expected}` because of return type
 
 hir_analysis_unconstrained_opaque_type = unconstrained opaque type
-    .note = `{$name}` must be used in combination with a concrete type within the same module
+    .note = `{$name}` must be used in combination with a concrete type within the same {$what}
 
 hir_analysis_missing_type_params =
     the type {$parameterCount ->
@@ -137,3 +137,19 @@ hir_analysis_expected_used_symbol = expected `used`, `used(compiler)` or `used(l
 hir_analysis_missing_parentheses_in_range = can't call method `{$method_name}` on type `{$ty_str}`
 
 hir_analysis_add_missing_parentheses_in_range = you must surround the range in parentheses to call its `{$func_name}` function
+
+hir_analysis_const_impl_for_non_const_trait =
+    const `impl` for trait `{$trait_name}` which is not marked with `#[const_trait]`
+    .suggestion = mark `{$trait_name}` as const
+    .note = marking a trait with `#[const_trait]` ensures all default method bodies are `const`
+    .adding = adding a non-const method body in the future would be a breaking change
+
+hir_analysis_const_bound_for_non_const_trait =
+    ~const can only be applied to `#[const_trait]` traits
+
+hir_analysis_self_in_impl_self =
+    `Self` is not valid in the self type of an impl block
+    .note = replace `Self` with a different type
+
+hir_analysis_op_trait_generic_params =
+    `{$method_name}` must not have any generic parameters
diff --git a/compiler/rustc_error_messages/locales/en-US/infer.ftl b/compiler/rustc_error_messages/locales/en-US/infer.ftl
index 18b3408b06ab..c9d83746d545 100644
--- a/compiler/rustc_error_messages/locales/en-US/infer.ftl
+++ b/compiler/rustc_error_messages/locales/en-US/infer.ftl
@@ -126,10 +126,10 @@ infer_data_lifetime_flow = ...but data with one lifetime flows into the other he
 infer_declared_multiple = this type is declared with multiple lifetimes...
 infer_types_declared_different = these two types are declared with different lifetimes...
 infer_data_flows = ...but data{$label_var1_exists ->
-    [true] -> {" "}from `{$label_var1}`
+    [true] {" "}from `{$label_var1}`
     *[false] -> {""}
 } flows{$label_var2_exists ->
-    [true] -> {" "}into `{$label_var2}`
+    [true] {" "}into `{$label_var2}`
     *[false] -> {""}
 } here
 
@@ -171,3 +171,4 @@ infer_msl_introduces_static = introduces a `'static` lifetime requirement
 infer_msl_unmet_req = because this has an unmet lifetime requirement
 infer_msl_trait_note = this has an implicit `'static` lifetime requirement
 infer_msl_trait_sugg = consider relaxing the implicit `'static` requirement
+infer_suggest_add_let_for_letchains = consider adding `let`
diff --git a/compiler/rustc_error_messages/locales/en-US/metadata.ftl b/compiler/rustc_error_messages/locales/en-US/metadata.ftl
index 08e553d9f158..c292ae9b32ab 100644
--- a/compiler/rustc_error_messages/locales/en-US/metadata.ftl
+++ b/compiler/rustc_error_messages/locales/en-US/metadata.ftl
@@ -150,12 +150,28 @@ metadata_no_multiple_global_alloc =
 metadata_prev_global_alloc =
     previous global allocator defined here
 
+metadata_no_multiple_alloc_error_handler =
+    cannot define multiple allocation error handlers
+    .label = cannot define a new allocation error handler
+
+metadata_prev_alloc_error_handler =
+    previous allocation error handler defined here
+
 metadata_conflicting_global_alloc =
     the `#[global_allocator]` in {$other_crate_name} conflicts with global allocator in: {$crate_name}
 
+metadata_conflicting_alloc_error_handler =
+    the `#[alloc_error_handler]` in {$other_crate_name} conflicts with allocation error handler in: {$crate_name}
+
 metadata_global_alloc_required =
     no global memory allocator found but one is required; link to std or add `#[global_allocator]` to a static item that implements the GlobalAlloc trait
 
+metadata_alloc_func_required =
+    `#[alloc_error_handler]` function required, but not found
+
+metadata_missing_alloc_error_handler =
+    use `#![feature(default_alloc_error_handler)]` for a default error handler
+
 metadata_no_transitive_needs_dep =
     the crate `{$crate_name}` cannot depend on a crate that needs {$needs_crate_name}, but it depends on `{$deps_crate_name}`
 
diff --git a/compiler/rustc_error_messages/locales/en-US/middle.ftl b/compiler/rustc_error_messages/locales/en-US/middle.ftl
index b9e4499d47f3..81d8e8a473bb 100644
--- a/compiler/rustc_error_messages/locales/en-US/middle.ftl
+++ b/compiler/rustc_error_messages/locales/en-US/middle.ftl
@@ -27,3 +27,7 @@ middle_values_too_big =
 
 middle_cannot_be_normalized =
     unable to determine layout for `{$ty}` because `{$failure_ty}` cannot be normalized
+
+middle_strict_coherence_needs_negative_coherence =
+    to use `strict_coherence` on this trait, the `with_negative_coherence` feature must be enabled
+    .label = due to this attribute
diff --git a/compiler/rustc_error_messages/locales/en-US/monomorphize.ftl b/compiler/rustc_error_messages/locales/en-US/monomorphize.ftl
index 42c84fdd2d14..48ddb54b79e7 100644
--- a/compiler/rustc_error_messages/locales/en-US/monomorphize.ftl
+++ b/compiler/rustc_error_messages/locales/en-US/monomorphize.ftl
@@ -21,6 +21,3 @@ monomorphize_large_assignments =
     moving {$size} bytes
     .label = value moved from here
     .note = The current maximum size is {$limit}, but it can be customized with the move_size_limit attribute: `#![move_size_limit = "..."]`
-
-monomorphize_requires_lang_item =
-    requires `{$lang_item}` lang_item
diff --git a/compiler/rustc_error_messages/locales/en-US/parser.ftl b/compiler/rustc_error_messages/locales/en-US/parser.ftl
index 13c368d1c585..4c7ce30097c9 100644
--- a/compiler/rustc_error_messages/locales/en-US/parser.ftl
+++ b/compiler/rustc_error_messages/locales/en-US/parser.ftl
@@ -112,6 +112,9 @@ parser_missing_semicolon_before_array = expected `;`, found `[`
 parser_invalid_block_macro_segment = cannot use a `block` macro fragment here
     .label = the `block` fragment is within this context
 
+parser_expect_dotdot_not_dotdotdot = expected `..`, found `...`
+    .suggestion = use `..` to fill in the rest of the fields
+
 parser_if_expression_missing_then_block = this `if` expression is missing a block after the condition
     .add_then_block = add a block here
     .condition_possibly_unfinished = this binary operation is possibly unfinished
@@ -122,6 +125,9 @@ parser_if_expression_missing_condition = missing condition for `if` expression
 
 parser_expected_expression_found_let = expected expression, found `let` statement
 
+parser_expect_eq_instead_of_eqeq = expected `=`, found `==`
+    .suggestion = consider using `=` here
+
 parser_expected_else_block = expected `{"{"}`, found {$first_tok}
     .label = expected an `if` or a block after this `else`
     .suggestion = add an `if` if this is the condition of a chained `else if` statement
@@ -369,3 +375,15 @@ parser_async_move_order_incorrect = the order of `move` and `async` is incorrect
 
 parser_double_colon_in_bound = expected `:` followed by trait or lifetime
     .suggestion = use single colon
+
+parser_fn_ptr_with_generics = function pointer types may not have generic parameters
+    .suggestion = consider moving the lifetime {$arity ->
+        [one] parameter
+        *[other] parameters
+    } to {$for_param_list_exists ->
+        [true] the
+        *[false] a
+    } `for` parameter list
+
+parser_invalid_identifier_with_leading_number = expected identifier, found number literal
+    .label = identifiers cannot start with a number
diff --git a/compiler/rustc_error_messages/locales/en-US/passes.ftl b/compiler/rustc_error_messages/locales/en-US/passes.ftl
index 4bc6bd9fb220..001e53d1d0e4 100644
--- a/compiler/rustc_error_messages/locales/en-US/passes.ftl
+++ b/compiler/rustc_error_messages/locales/en-US/passes.ftl
@@ -47,7 +47,10 @@ passes_no_coverage_not_coverable =
 
 passes_should_be_applied_to_fn =
     attribute should be applied to a function definition
-    .label = not a function definition
+    .label = {$on_crate ->
+        [true] cannot be applied to crates
+        *[false] not a function definition
+    }
 
 passes_naked_tracked_caller =
     cannot use `#[track_caller]` with `#[naked]`
@@ -367,12 +370,6 @@ passes_unknown_external_lang_item =
 passes_missing_panic_handler =
     `#[panic_handler]` function required, but not found
 
-passes_alloc_func_required =
-    `#[alloc_error_handler]` function required, but not found
-
-passes_missing_alloc_error_handler =
-    use `#![feature(default_alloc_error_handler)]` for a default error handler
-
 passes_missing_lang_item =
     language item required, but not found: `{$name}`
     .note = this can occur when a binary crate with `#![no_std]` is compiled for a target where `{$name}` is defined in the standard library
@@ -457,8 +454,14 @@ passes_break_inside_async_block =
     .async_block_label = enclosing `async` block
 
 passes_outside_loop =
-    `{$name}` outside of a loop
-    .label = cannot `{$name}` outside of a loop
+    `{$name}` outside of a loop{$is_break ->
+        [true] {" or labeled block"}
+        *[false] {""}
+    }
+    .label = cannot `{$name}` outside of a loop{$is_break ->
+        [true] {" or labeled block"}
+        *[false] {""}
+    }
 
 passes_unlabeled_in_labeled_block =
     unlabeled `{$cf_type}` inside of a labeled block
@@ -671,3 +674,36 @@ passes_missing_const_err =
     attributes `#[rustc_const_unstable]` and `#[rustc_const_stable]` require the function or method to be `const`
     .help = make the function or method const
     .label = attribute specified here
+
+passes_dead_codes =
+    { $multiple ->
+      *[true] multiple {$descr}s are
+       [false] { $num ->
+         [one] {$descr} {$name_list} is
+        *[other] {$descr}s {$name_list} are
+       }
+    } never {$participle}
+
+passes_change_fields_to_be_of_unit_type =
+    consider changing the { $num ->
+      [one] field
+     *[other] fields
+    } to be of unit type to suppress this warning while preserving the field numbering, or remove the { $num ->
+      [one] field
+     *[other] fields
+    }
+
+passes_parent_info =
+    {$num ->
+      [one] {$descr}
+     *[other] {$descr}s
+    } in this {$parent_descr}
+
+passes_ignored_derived_impls =
+    `{$name}` has {$trait_list_len ->
+      [one] a derived impl
+     *[other] derived impls
+    } for the {$trait_list_len ->
+      [one] trait {$trait_list}, but this is
+     *[other] traits {$trait_list}, but these are
+    } intentionally ignored during dead code analysis
diff --git a/compiler/rustc_error_messages/src/lib.rs b/compiler/rustc_error_messages/src/lib.rs
index 9465051dd103..0b1b75471a66 100644
--- a/compiler/rustc_error_messages/src/lib.rs
+++ b/compiler/rustc_error_messages/src/lib.rs
@@ -30,7 +30,8 @@ use intl_memoizer::concurrent::IntlLangMemoizer;
 #[cfg(not(parallel_compiler))]
 use intl_memoizer::IntlLangMemoizer;
 
-pub use fluent_bundle::{FluentArgs, FluentError, FluentValue};
+pub use fluent_bundle::{self, FluentArgs, FluentError, FluentValue};
+
 pub use unic_langid::{langid, LanguageIdentifier};
 
 // Generates `DEFAULT_LOCALE_RESOURCES` static and `fluent_generated` module.
@@ -42,6 +43,7 @@ fluent_messages! {
     borrowck => "../locales/en-US/borrowck.ftl",
     builtin_macros => "../locales/en-US/builtin_macros.ftl",
     codegen_gcc => "../locales/en-US/codegen_gcc.ftl",
+    codegen_llvm => "../locales/en-US/codegen_llvm.ftl",
     codegen_ssa => "../locales/en-US/codegen_ssa.ftl",
     compiletest => "../locales/en-US/compiletest.ftl",
     const_eval => "../locales/en-US/const_eval.ftl",
diff --git a/compiler/rustc_errors/src/annotate_snippet_emitter_writer.rs b/compiler/rustc_errors/src/annotate_snippet_emitter_writer.rs
index f14b8ee3254f..c450c276366e 100644
--- a/compiler/rustc_errors/src/annotate_snippet_emitter_writer.rs
+++ b/compiler/rustc_errors/src/annotate_snippet_emitter_writer.rs
@@ -52,7 +52,6 @@ impl Emitter for AnnotateSnippetEmitterWriter {
         let (mut primary_span, suggestions) = self.primary_span_formatted(&diag, &fluent_args);
 
         self.fix_multispans_in_extern_macros_and_render_macro_backtrace(
-            &self.source_map,
             &mut primary_span,
             &mut children,
             &diag.level,
diff --git a/compiler/rustc_errors/src/diagnostic.rs b/compiler/rustc_errors/src/diagnostic.rs
index a63fc0ca285d..66c986977ecc 100644
--- a/compiler/rustc_errors/src/diagnostic.rs
+++ b/compiler/rustc_errors/src/diagnostic.rs
@@ -12,6 +12,7 @@ use rustc_span::{Span, DUMMY_SP};
 use std::borrow::Cow;
 use std::fmt;
 use std::hash::{Hash, Hasher};
+use std::panic::Location;
 
 /// Error type for `Diagnostic`'s `suggestions` field, indicating that
 /// `.disable_suggestions()` was called on the `Diagnostic`.
@@ -43,6 +44,15 @@ pub trait IntoDiagnosticArg {
     fn into_diagnostic_arg(self) -> DiagnosticArgValue<'static>;
 }
 
+impl<'source> IntoDiagnosticArg for DiagnosticArgValue<'source> {
+    fn into_diagnostic_arg(self) -> DiagnosticArgValue<'static> {
+        match self {
+            DiagnosticArgValue::Str(s) => DiagnosticArgValue::Str(Cow::Owned(s.into_owned())),
+            DiagnosticArgValue::Number(n) => DiagnosticArgValue::Number(n),
+        }
+    }
+}
+
 impl<'source> Into<FluentValue<'source>> for DiagnosticArgValue<'source> {
     fn into(self) -> FluentValue<'source> {
         match self {
@@ -54,8 +64,7 @@ impl<'source> Into<FluentValue<'source>> for DiagnosticArgValue<'source> {
 
 /// Trait implemented by error types. This should not be implemented manually. Instead, use
 /// `#[derive(Subdiagnostic)]` -- see [rustc_macros::Subdiagnostic].
-#[cfg_attr(bootstrap, rustc_diagnostic_item = "AddSubdiagnostic")]
-#[cfg_attr(not(bootstrap), rustc_diagnostic_item = "AddToDiagnostic")]
+#[rustc_diagnostic_item = "AddToDiagnostic"]
 pub trait AddToDiagnostic
 where
     Self: Sized,
@@ -107,6 +116,31 @@ pub struct Diagnostic {
     /// If diagnostic is from Lint, custom hash function ignores notes
     /// otherwise hash is based on the all the fields
     pub is_lint: bool,
+
+    /// With `-Ztrack_diagnostics` enabled,
+    /// we print where in rustc this error was emitted.
+    pub emitted_at: DiagnosticLocation,
+}
+
+#[derive(Clone, Debug, Encodable, Decodable)]
+pub struct DiagnosticLocation {
+    file: Cow<'static, str>,
+    line: u32,
+    col: u32,
+}
+
+impl DiagnosticLocation {
+    #[track_caller]
+    fn caller() -> Self {
+        let loc = Location::caller();
+        DiagnosticLocation { file: loc.file().into(), line: loc.line(), col: loc.column() }
+    }
+}
+
+impl fmt::Display for DiagnosticLocation {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}:{}:{}", self.file, self.line, self.col)
+    }
 }
 
 #[derive(Clone, Debug, PartialEq, Eq, Hash, Encodable, Decodable)]
@@ -173,10 +207,28 @@ impl StringPart {
 }
 
 impl Diagnostic {
+    #[track_caller]
     pub fn new<M: Into<DiagnosticMessage>>(level: Level, message: M) -> Self {
         Diagnostic::new_with_code(level, None, message)
     }
 
+    #[track_caller]
+    pub fn new_with_messages(level: Level, messages: Vec<(DiagnosticMessage, Style)>) -> Self {
+        Diagnostic {
+            level,
+            message: messages,
+            code: None,
+            span: MultiSpan::new(),
+            children: vec![],
+            suggestions: Ok(vec![]),
+            args: Default::default(),
+            sort_span: DUMMY_SP,
+            is_lint: false,
+            emitted_at: DiagnosticLocation::caller(),
+        }
+    }
+
+    #[track_caller]
     pub fn new_with_code<M: Into<DiagnosticMessage>>(
         level: Level,
         code: Option<DiagnosticId>,
@@ -192,6 +244,7 @@ impl Diagnostic {
             args: Default::default(),
             sort_span: DUMMY_SP,
             is_lint: false,
+            emitted_at: DiagnosticLocation::caller(),
         }
     }
 
@@ -688,10 +741,28 @@ impl Diagnostic {
         &mut self,
         sp: Span,
         msg: impl Into<SubdiagnosticMessage>,
-        suggestions: impl Iterator<Item = String>,
+        suggestions: impl IntoIterator<Item = String>,
         applicability: Applicability,
     ) -> &mut Self {
-        let mut suggestions: Vec<_> = suggestions.collect();
+        self.span_suggestions_with_style(
+            sp,
+            msg,
+            suggestions,
+            applicability,
+            SuggestionStyle::ShowCode,
+        )
+    }
+
+    /// [`Diagnostic::span_suggestions()`] but you can set the [`SuggestionStyle`].
+    pub fn span_suggestions_with_style(
+        &mut self,
+        sp: Span,
+        msg: impl Into<SubdiagnosticMessage>,
+        suggestions: impl IntoIterator<Item = String>,
+        applicability: Applicability,
+        style: SuggestionStyle,
+    ) -> &mut Self {
+        let mut suggestions: Vec<_> = suggestions.into_iter().collect();
         suggestions.sort();
 
         debug_assert!(
@@ -706,21 +777,22 @@ impl Diagnostic {
         self.push_suggestion(CodeSuggestion {
             substitutions,
             msg: self.subdiagnostic_message_to_diagnostic_message(msg),
-            style: SuggestionStyle::ShowCode,
+            style,
             applicability,
         });
         self
     }
 
-    /// Prints out a message with multiple suggested edits of the code.
-    /// See also [`Diagnostic::span_suggestion()`].
+    /// Prints out a message with multiple suggested edits of the code, where each edit consists of
+    /// multiple parts.
+    /// See also [`Diagnostic::multipart_suggestion()`].
     pub fn multipart_suggestions(
         &mut self,
         msg: impl Into<SubdiagnosticMessage>,
-        suggestions: impl Iterator<Item = Vec<(Span, String)>>,
+        suggestions: impl IntoIterator<Item = Vec<(Span, String)>>,
         applicability: Applicability,
     ) -> &mut Self {
-        let suggestions: Vec<_> = suggestions.collect();
+        let suggestions: Vec<_> = suggestions.into_iter().collect();
         debug_assert!(
             !(suggestions
                 .iter()
@@ -745,6 +817,7 @@ impl Diagnostic {
         });
         self
     }
+
     /// Prints out a message with a suggested edit of the code. If the suggestion is presented
     /// inline, it will only show the message and not the suggestion.
     ///
@@ -882,6 +955,13 @@ impl Diagnostic {
         self
     }
 
+    pub fn replace_args(
+        &mut self,
+        args: FxHashMap<DiagnosticArgName<'static>, DiagnosticArgValue<'static>>,
+    ) {
+        self.args = args;
+    }
+
     pub fn styled_message(&self) -> &[(DiagnosticMessage, Style)] {
         &self.message
     }
diff --git a/compiler/rustc_errors/src/diagnostic_builder.rs b/compiler/rustc_errors/src/diagnostic_builder.rs
index 9b41234dcfb6..a2ed988643ff 100644
--- a/compiler/rustc_errors/src/diagnostic_builder.rs
+++ b/compiler/rustc_errors/src/diagnostic_builder.rs
@@ -16,8 +16,7 @@ use std::thread::panicking;
 
 /// Trait implemented by error types. This should not be implemented manually. Instead, use
 /// `#[derive(Diagnostic)]` -- see [rustc_macros::Diagnostic].
-#[cfg_attr(bootstrap, rustc_diagnostic_item = "SessionDiagnostic")]
-#[cfg_attr(not(bootstrap), rustc_diagnostic_item = "IntoDiagnostic")]
+#[rustc_diagnostic_item = "IntoDiagnostic"]
 pub trait IntoDiagnostic<'a, T: EmissionGuarantee = ErrorGuaranteed> {
     /// Write out as a diagnostic out of `Handler`.
     #[must_use]
@@ -133,6 +132,7 @@ mod sealed_level_is_error {
 impl<'a> DiagnosticBuilder<'a, ErrorGuaranteed> {
     /// Convenience function for internal use, clients should use one of the
     /// `struct_*` methods on [`Handler`].
+    #[track_caller]
     pub(crate) fn new_guaranteeing_error<M: Into<DiagnosticMessage>, const L: Level>(
         handler: &'a Handler,
         message: M,
@@ -196,6 +196,7 @@ impl EmissionGuarantee for ErrorGuaranteed {
         }
     }
 
+    #[track_caller]
     fn make_diagnostic_builder(
         handler: &Handler,
         msg: impl Into<DiagnosticMessage>,
@@ -209,6 +210,7 @@ impl EmissionGuarantee for ErrorGuaranteed {
 impl<'a> DiagnosticBuilder<'a, ()> {
     /// Convenience function for internal use, clients should use one of the
     /// `struct_*` methods on [`Handler`].
+    #[track_caller]
     pub(crate) fn new<M: Into<DiagnosticMessage>>(
         handler: &'a Handler,
         level: Level,
@@ -220,6 +222,7 @@ impl<'a> DiagnosticBuilder<'a, ()> {
 
     /// Creates a new `DiagnosticBuilder` with an already constructed
     /// diagnostic.
+    #[track_caller]
     pub(crate) fn new_diagnostic(handler: &'a Handler, diagnostic: Diagnostic) -> Self {
         debug!("Created new diagnostic");
         Self {
@@ -308,6 +311,7 @@ impl EmissionGuarantee for Noted {
 impl<'a> DiagnosticBuilder<'a, !> {
     /// Convenience function for internal use, clients should use one of the
     /// `struct_*` methods on [`Handler`].
+    #[track_caller]
     pub(crate) fn new_fatal(handler: &'a Handler, message: impl Into<DiagnosticMessage>) -> Self {
         let diagnostic = Diagnostic::new_with_code(Level::Fatal, None, message);
         Self::new_diagnostic_fatal(handler, diagnostic)
@@ -477,9 +481,9 @@ impl<'a, G: EmissionGuarantee> DiagnosticBuilder<'a, G> {
     /// In the meantime, though, callsites are required to deal with the "bug"
     /// locally in whichever way makes the most sense.
     #[track_caller]
-    pub fn delay_as_bug(&mut self) {
+    pub fn delay_as_bug(&mut self) -> G {
         self.downgrade_to_delayed_bug();
-        self.emit();
+        self.emit()
     }
 
     forward!(
@@ -594,13 +598,13 @@ impl<'a, G: EmissionGuarantee> DiagnosticBuilder<'a, G> {
         &mut self,
         sp: Span,
         msg: impl Into<SubdiagnosticMessage>,
-        suggestions: impl Iterator<Item = String>,
+        suggestions: impl IntoIterator<Item = String>,
         applicability: Applicability,
     ) -> &mut Self);
     forward!(pub fn multipart_suggestions(
         &mut self,
         msg: impl Into<SubdiagnosticMessage>,
-        suggestions: impl Iterator<Item = Vec<(Span, String)>>,
+        suggestions: impl IntoIterator<Item = Vec<(Span, String)>>,
         applicability: Applicability,
     ) -> &mut Self);
     forward!(pub fn span_suggestion_short(
diff --git a/compiler/rustc_errors/src/diagnostic_impls.rs b/compiler/rustc_errors/src/diagnostic_impls.rs
index 7640b2919f78..c6035705e39f 100644
--- a/compiler/rustc_errors/src/diagnostic_impls.rs
+++ b/compiler/rustc_errors/src/diagnostic_impls.rs
@@ -11,8 +11,10 @@ use rustc_target::abi::TargetDataLayoutErrors;
 use rustc_target::spec::{PanicStrategy, SplitDebuginfo, StackProtector, TargetTriple};
 use std::borrow::Cow;
 use std::fmt;
+use std::fmt::Write;
 use std::num::ParseIntError;
 use std::path::{Path, PathBuf};
+use std::process::ExitStatus;
 
 pub struct DiagnosticArgFromDisplay<'a>(pub &'a dyn fmt::Display);
 
@@ -58,6 +60,7 @@ into_diagnostic_arg_using_display!(
     i128,
     u128,
     std::io::Error,
+    std::boxed::Box<dyn std::error::Error>,
     std::num::NonZeroU32,
     hir::Target,
     Edition,
@@ -66,7 +69,8 @@ into_diagnostic_arg_using_display!(
     ParseIntError,
     StackProtector,
     &TargetTriple,
-    SplitDebuginfo
+    SplitDebuginfo,
+    ExitStatus,
 );
 
 impl IntoDiagnosticArg for bool {
@@ -103,6 +107,12 @@ impl IntoDiagnosticArg for String {
     }
 }
 
+impl<'a> IntoDiagnosticArg for Cow<'a, str> {
+    fn into_diagnostic_arg(self) -> DiagnosticArgValue<'static> {
+        DiagnosticArgValue::Str(Cow::Owned(self.into_owned()))
+    }
+}
+
 impl<'a> IntoDiagnosticArg for &'a Path {
     fn into_diagnostic_arg(self) -> DiagnosticArgValue<'static> {
         DiagnosticArgValue::Str(Cow::Owned(self.display().to_string()))
@@ -170,6 +180,37 @@ impl IntoDiagnosticArg for Level {
     }
 }
 
+#[derive(Clone)]
+pub struct DiagnosticSymbolList(Vec<Symbol>);
+
+impl From<Vec<Symbol>> for DiagnosticSymbolList {
+    fn from(v: Vec<Symbol>) -> Self {
+        DiagnosticSymbolList(v)
+    }
+}
+
+impl IntoDiagnosticArg for DiagnosticSymbolList {
+    fn into_diagnostic_arg(self) -> DiagnosticArgValue<'static> {
+        // FIXME: replace the logic here with a real list formatter
+        let symbols = match &self.0[..] {
+            [symbol] => format!("`{symbol}`"),
+            [symbol, last] => {
+                format!("`{symbol}` and `{last}`",)
+            }
+            [symbols @ .., last] => {
+                let mut result = String::new();
+                for symbol in symbols {
+                    write!(result, "`{symbol}`, ").unwrap();
+                }
+                write!(result, "and `{last}`").unwrap();
+                result
+            }
+            [] => unreachable!(),
+        };
+        DiagnosticArgValue::Str(Cow::Owned(symbols))
+    }
+}
+
 impl IntoDiagnostic<'_, !> for TargetDataLayoutErrors<'_> {
     fn into_diagnostic(self, handler: &Handler) -> DiagnosticBuilder<'_, !> {
         let mut diag;
diff --git a/compiler/rustc_errors/src/emitter.rs b/compiler/rustc_errors/src/emitter.rs
index cd6413bc3ec6..55c7997a5136 100644
--- a/compiler/rustc_errors/src/emitter.rs
+++ b/compiler/rustc_errors/src/emitter.rs
@@ -16,10 +16,10 @@ use crate::snippet::{Annotation, AnnotationType, Line, MultilineAnnotation, Styl
 use crate::styled_buffer::StyledBuffer;
 use crate::translation::{to_fluent_args, Translate};
 use crate::{
-    CodeSuggestion, Diagnostic, DiagnosticId, DiagnosticMessage, FluentBundle, Handler,
-    LazyFallbackBundle, Level, MultiSpan, SubDiagnostic, SubstitutionHighlight, SuggestionStyle,
+    diagnostic::DiagnosticLocation, CodeSuggestion, Diagnostic, DiagnosticId, DiagnosticMessage,
+    FluentBundle, Handler, LazyFallbackBundle, Level, MultiSpan, SubDiagnostic,
+    SubstitutionHighlight, SuggestionStyle,
 };
-
 use rustc_lint_defs::pluralize;
 
 use rustc_data_structures::fx::{FxHashMap, FxIndexMap};
@@ -64,6 +64,7 @@ impl HumanReadableErrorType {
         teach: bool,
         diagnostic_width: Option<usize>,
         macro_backtrace: bool,
+        track_diagnostics: bool,
     ) -> EmitterWriter {
         let (short, color_config) = self.unzip();
         let color = color_config.suggests_using_colors();
@@ -77,6 +78,7 @@ impl HumanReadableErrorType {
             color,
             diagnostic_width,
             macro_backtrace,
+            track_diagnostics,
         )
     }
 }
@@ -312,7 +314,6 @@ pub trait Emitter: Translate {
 
     fn fix_multispans_in_extern_macros_and_render_macro_backtrace(
         &self,
-        source_map: &Option<Lrc<SourceMap>>,
         span: &mut MultiSpan,
         children: &mut Vec<SubDiagnostic>,
         level: &Level,
@@ -338,7 +339,7 @@ pub trait Emitter: Translate {
             .collect();
 
         if !backtrace {
-            self.fix_multispans_in_extern_macros(source_map, span, children);
+            self.fix_multispans_in_extern_macros(span, children);
         }
 
         self.render_multispans_macro_backtrace(span, children, backtrace);
@@ -478,15 +479,13 @@ pub trait Emitter: Translate {
     // this will change the span to point at the use site.
     fn fix_multispans_in_extern_macros(
         &self,
-        source_map: &Option<Lrc<SourceMap>>,
         span: &mut MultiSpan,
         children: &mut Vec<SubDiagnostic>,
     ) {
-        let Some(source_map) = source_map else { return };
         debug!("fix_multispans_in_extern_macros: before: span={:?} children={:?}", span, children);
-        self.fix_multispan_in_extern_macros(source_map, span);
+        self.fix_multispan_in_extern_macros(span);
         for child in children.iter_mut() {
-            self.fix_multispan_in_extern_macros(source_map, &mut child.span);
+            self.fix_multispan_in_extern_macros(&mut child.span);
         }
         debug!("fix_multispans_in_extern_macros: after: span={:?} children={:?}", span, children);
     }
@@ -494,7 +493,8 @@ pub trait Emitter: Translate {
     // This "fixes" MultiSpans that contain `Span`s pointing to locations inside of external macros.
     // Since these locations are often difficult to read,
     // we move these spans from the external macros to their corresponding use site.
-    fn fix_multispan_in_extern_macros(&self, source_map: &Lrc<SourceMap>, span: &mut MultiSpan) {
+    fn fix_multispan_in_extern_macros(&self, span: &mut MultiSpan) {
+        let Some(source_map) = self.source_map() else { return };
         // First, find all the spans in external macros and point instead at their use site.
         let replacements: Vec<(Span, Span)> = span
             .primary_spans()
@@ -542,7 +542,6 @@ impl Emitter for EmitterWriter {
         debug!("emit_diagnostic: suggestions={:?}", suggestions);
 
         self.fix_multispans_in_extern_macros_and_render_macro_backtrace(
-            &self.sm,
             &mut primary_span,
             &mut children,
             &diag.level,
@@ -557,6 +556,7 @@ impl Emitter for EmitterWriter {
             &primary_span,
             &children,
             &suggestions,
+            self.track_diagnostics.then_some(&diag.emitted_at),
         );
     }
 
@@ -650,6 +650,7 @@ pub struct EmitterWriter {
     diagnostic_width: Option<usize>,
 
     macro_backtrace: bool,
+    track_diagnostics: bool,
 }
 
 #[derive(Debug)]
@@ -669,6 +670,7 @@ impl EmitterWriter {
         teach: bool,
         diagnostic_width: Option<usize>,
         macro_backtrace: bool,
+        track_diagnostics: bool,
     ) -> EmitterWriter {
         let dst = Destination::from_stderr(color_config);
         EmitterWriter {
@@ -681,6 +683,7 @@ impl EmitterWriter {
             ui_testing: false,
             diagnostic_width,
             macro_backtrace,
+            track_diagnostics,
         }
     }
 
@@ -694,6 +697,7 @@ impl EmitterWriter {
         colored: bool,
         diagnostic_width: Option<usize>,
         macro_backtrace: bool,
+        track_diagnostics: bool,
     ) -> EmitterWriter {
         EmitterWriter {
             dst: Raw(dst, colored),
@@ -705,6 +709,7 @@ impl EmitterWriter {
             ui_testing: false,
             diagnostic_width,
             macro_backtrace,
+            track_diagnostics,
         }
     }
 
@@ -1327,6 +1332,7 @@ impl EmitterWriter {
         level: &Level,
         max_line_num_len: usize,
         is_secondary: bool,
+        emitted_at: Option<&DiagnosticLocation>,
     ) -> io::Result<()> {
         let mut buffer = StyledBuffer::new();
 
@@ -1377,7 +1383,6 @@ impl EmitterWriter {
                 }
             }
         }
-
         let mut annotated_files = FileWithAnnotatedLines::collect_annotations(self, args, msp);
 
         // Make sure our primary file comes first
@@ -1653,6 +1658,12 @@ impl EmitterWriter {
             }
         }
 
+        if let Some(tracked) = emitted_at {
+            let track = format!("-Ztrack-diagnostics: created at {tracked}");
+            let len = buffer.num_lines();
+            buffer.append(len, &track, Style::NoStyle);
+        }
+
         // final step: take our styled buffer, render it, then output it
         emit_to_destination(&buffer.render(), level, &mut self.dst, self.short_message)?;
 
@@ -1977,6 +1988,7 @@ impl EmitterWriter {
         span: &MultiSpan,
         children: &[SubDiagnostic],
         suggestions: &[CodeSuggestion],
+        emitted_at: Option<&DiagnosticLocation>,
     ) {
         let max_line_num_len = if self.ui_testing {
             ANONYMIZED_LINE_NUM.len()
@@ -1985,7 +1997,16 @@ impl EmitterWriter {
             num_decimal_digits(n)
         };
 
-        match self.emit_message_default(span, message, args, code, level, max_line_num_len, false) {
+        match self.emit_message_default(
+            span,
+            message,
+            args,
+            code,
+            level,
+            max_line_num_len,
+            false,
+            emitted_at,
+        ) {
             Ok(()) => {
                 if !children.is_empty()
                     || suggestions.iter().any(|s| s.style != SuggestionStyle::CompletelyHidden)
@@ -2014,6 +2035,7 @@ impl EmitterWriter {
                             &child.level,
                             max_line_num_len,
                             true,
+                            None,
                         ) {
                             panic!("failed to emit error: {}", err);
                         }
@@ -2030,6 +2052,7 @@ impl EmitterWriter {
                                 &Level::Help,
                                 max_line_num_len,
                                 true,
+                                None,
                             ) {
                                 panic!("failed to emit error: {}", e);
                             }
@@ -2187,22 +2210,45 @@ impl FileWithAnnotatedLines {
 
         if let Some(ref sm) = emitter.source_map() {
             for span_label in msp.span_labels() {
+                let fixup_lo_hi = |span: Span| {
+                    let lo = sm.lookup_char_pos(span.lo());
+                    let mut hi = sm.lookup_char_pos(span.hi());
+
+                    // Watch out for "empty spans". If we get a span like 6..6, we
+                    // want to just display a `^` at 6, so convert that to
+                    // 6..7. This is degenerate input, but it's best to degrade
+                    // gracefully -- and the parser likes to supply a span like
+                    // that for EOF, in particular.
+
+                    if lo.col_display == hi.col_display && lo.line == hi.line {
+                        hi.col_display += 1;
+                    }
+                    (lo, hi)
+                };
+
                 if span_label.span.is_dummy() {
+                    if let Some(span) = msp.primary_span() {
+                        // if we don't know where to render the annotation, emit it as a note
+                        // on the primary span.
+
+                        let (lo, hi) = fixup_lo_hi(span);
+
+                        let ann = Annotation {
+                            start_col: lo.col_display,
+                            end_col: hi.col_display,
+                            is_primary: span_label.is_primary,
+                            label: span_label
+                                .label
+                                .as_ref()
+                                .map(|m| emitter.translate_message(m, args).to_string()),
+                            annotation_type: AnnotationType::Singleline,
+                        };
+                        add_annotation_to_file(&mut output, lo.file, lo.line, ann);
+                    }
                     continue;
                 }
 
-                let lo = sm.lookup_char_pos(span_label.span.lo());
-                let mut hi = sm.lookup_char_pos(span_label.span.hi());
-
-                // Watch out for "empty spans". If we get a span like 6..6, we
-                // want to just display a `^` at 6, so convert that to
-                // 6..7. This is degenerate input, but it's best to degrade
-                // gracefully -- and the parser likes to supply a span like
-                // that for EOF, in particular.
-
-                if lo.col_display == hi.col_display && lo.line == hi.line {
-                    hi.col_display += 1;
-                }
+                let (lo, hi) = fixup_lo_hi(span_label.span);
 
                 if lo.line != hi.line {
                     let ml = MultilineAnnotation {
diff --git a/compiler/rustc_errors/src/json.rs b/compiler/rustc_errors/src/json.rs
index 4cc7be47fc2c..c4498eafa4ea 100644
--- a/compiler/rustc_errors/src/json.rs
+++ b/compiler/rustc_errors/src/json.rs
@@ -45,6 +45,7 @@ pub struct JsonEmitter {
     json_rendered: HumanReadableErrorType,
     diagnostic_width: Option<usize>,
     macro_backtrace: bool,
+    track_diagnostics: bool,
 }
 
 impl JsonEmitter {
@@ -57,6 +58,7 @@ impl JsonEmitter {
         json_rendered: HumanReadableErrorType,
         diagnostic_width: Option<usize>,
         macro_backtrace: bool,
+        track_diagnostics: bool,
     ) -> JsonEmitter {
         JsonEmitter {
             dst: Box::new(io::BufWriter::new(io::stderr())),
@@ -69,6 +71,7 @@ impl JsonEmitter {
             json_rendered,
             diagnostic_width,
             macro_backtrace,
+            track_diagnostics,
         }
     }
 
@@ -79,6 +82,7 @@ impl JsonEmitter {
         fallback_bundle: LazyFallbackBundle,
         diagnostic_width: Option<usize>,
         macro_backtrace: bool,
+        track_diagnostics: bool,
     ) -> JsonEmitter {
         let file_path_mapping = FilePathMapping::empty();
         JsonEmitter::stderr(
@@ -90,6 +94,7 @@ impl JsonEmitter {
             json_rendered,
             diagnostic_width,
             macro_backtrace,
+            track_diagnostics,
         )
     }
 
@@ -103,6 +108,7 @@ impl JsonEmitter {
         json_rendered: HumanReadableErrorType,
         diagnostic_width: Option<usize>,
         macro_backtrace: bool,
+        track_diagnostics: bool,
     ) -> JsonEmitter {
         JsonEmitter {
             dst,
@@ -115,6 +121,7 @@ impl JsonEmitter {
             json_rendered,
             diagnostic_width,
             macro_backtrace,
+            track_diagnostics,
         }
     }
 
@@ -350,6 +357,7 @@ impl Diagnostic {
                 false,
                 je.diagnostic_width,
                 je.macro_backtrace,
+                je.track_diagnostics,
             )
             .ui_testing(je.ui_testing)
             .emit_diagnostic(diag);
diff --git a/compiler/rustc_errors/src/json/tests.rs b/compiler/rustc_errors/src/json/tests.rs
index d940d14e1db9..f131468971b5 100644
--- a/compiler/rustc_errors/src/json/tests.rs
+++ b/compiler/rustc_errors/src/json/tests.rs
@@ -59,6 +59,7 @@ fn test_positions(code: &str, span: (u32, u32), expected_output: SpanTestData) {
             HumanReadableErrorType::Short(ColorConfig::Never),
             None,
             false,
+            false,
         );
 
         let span = Span::with_root_ctxt(BytePos(span.0), BytePos(span.1));
diff --git a/compiler/rustc_errors/src/lib.rs b/compiler/rustc_errors/src/lib.rs
index 0963ea71f802..170d4341ae71 100644
--- a/compiler/rustc_errors/src/lib.rs
+++ b/compiler/rustc_errors/src/lib.rs
@@ -376,7 +376,7 @@ pub use diagnostic::{
     DiagnosticStyledString, IntoDiagnosticArg, SubDiagnostic,
 };
 pub use diagnostic_builder::{DiagnosticBuilder, EmissionGuarantee, Noted};
-pub use diagnostic_impls::DiagnosticArgFromDisplay;
+pub use diagnostic_impls::{DiagnosticArgFromDisplay, DiagnosticSymbolList};
 use std::backtrace::Backtrace;
 
 /// A handler deals with errors and other compiler output.
@@ -492,6 +492,8 @@ pub struct HandlerFlags {
     pub macro_backtrace: bool,
     /// If true, identical diagnostics are reported only once.
     pub deduplicate_diagnostics: bool,
+    /// Track where errors are created. Enabled with `-Ztrack-diagnostics`.
+    pub track_diagnostics: bool,
 }
 
 impl Drop for HandlerInner {
@@ -559,6 +561,7 @@ impl Handler {
             false,
             None,
             flags.macro_backtrace,
+            flags.track_diagnostics,
         ));
         Self::with_emitter_and_flags(emitter, flags)
     }
@@ -664,6 +667,7 @@ impl Handler {
 
     /// Construct a builder with the `msg` at the level appropriate for the specific `EmissionGuarantee`.
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_diagnostic<G: EmissionGuarantee>(
         &self,
         msg: impl Into<DiagnosticMessage>,
@@ -677,6 +681,7 @@ impl Handler {
     /// * `can_emit_warnings` is `true`
     /// * `is_force_warn` was set in `DiagnosticId::Lint`
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_span_warn(
         &self,
         span: impl Into<MultiSpan>,
@@ -693,6 +698,7 @@ impl Handler {
     /// Attempting to `.emit()` the builder will only emit if either:
     /// * `can_emit_warnings` is `true`
     /// * `is_force_warn` was set in `DiagnosticId::Lint`
+    #[track_caller]
     pub fn struct_span_warn_with_expectation(
         &self,
         span: impl Into<MultiSpan>,
@@ -706,6 +712,7 @@ impl Handler {
 
     /// Construct a builder at the `Allow` level at the given `span` and with the `msg`.
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_span_allow(
         &self,
         span: impl Into<MultiSpan>,
@@ -719,6 +726,7 @@ impl Handler {
     /// Construct a builder at the `Warning` level at the given `span` and with the `msg`.
     /// Also include a code.
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_span_warn_with_code(
         &self,
         span: impl Into<MultiSpan>,
@@ -736,6 +744,7 @@ impl Handler {
     /// * `can_emit_warnings` is `true`
     /// * `is_force_warn` was set in `DiagnosticId::Lint`
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_warn(&self, msg: impl Into<DiagnosticMessage>) -> DiagnosticBuilder<'_, ()> {
         DiagnosticBuilder::new(self, Level::Warning(None), msg)
     }
@@ -746,6 +755,7 @@ impl Handler {
     /// Attempting to `.emit()` the builder will only emit if either:
     /// * `can_emit_warnings` is `true`
     /// * `is_force_warn` was set in `DiagnosticId::Lint`
+    #[track_caller]
     pub fn struct_warn_with_expectation(
         &self,
         msg: impl Into<DiagnosticMessage>,
@@ -756,12 +766,14 @@ impl Handler {
 
     /// Construct a builder at the `Allow` level with the `msg`.
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_allow(&self, msg: impl Into<DiagnosticMessage>) -> DiagnosticBuilder<'_, ()> {
         DiagnosticBuilder::new(self, Level::Allow, msg)
     }
 
     /// Construct a builder at the `Expect` level with the `msg`.
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_expect(
         &self,
         msg: impl Into<DiagnosticMessage>,
@@ -772,6 +784,7 @@ impl Handler {
 
     /// Construct a builder at the `Error` level at the given `span` and with the `msg`.
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_span_err(
         &self,
         span: impl Into<MultiSpan>,
@@ -784,6 +797,7 @@ impl Handler {
 
     /// Construct a builder at the `Error` level at the given `span`, with the `msg`, and `code`.
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_span_err_with_code(
         &self,
         span: impl Into<MultiSpan>,
@@ -798,6 +812,7 @@ impl Handler {
     /// Construct a builder at the `Error` level with the `msg`.
     // FIXME: This method should be removed (every error should have an associated error code).
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_err(
         &self,
         msg: impl Into<DiagnosticMessage>,
@@ -807,12 +822,14 @@ impl Handler {
 
     /// This should only be used by `rustc_middle::lint::struct_lint_level`. Do not use it for hard errors.
     #[doc(hidden)]
+    #[track_caller]
     pub fn struct_err_lint(&self, msg: impl Into<DiagnosticMessage>) -> DiagnosticBuilder<'_, ()> {
         DiagnosticBuilder::new(self, Level::Error { lint: true }, msg)
     }
 
     /// Construct a builder at the `Error` level with the `msg` and the `code`.
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_err_with_code(
         &self,
         msg: impl Into<DiagnosticMessage>,
@@ -825,6 +842,7 @@ impl Handler {
 
     /// Construct a builder at the `Warn` level with the `msg` and the `code`.
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_warn_with_code(
         &self,
         msg: impl Into<DiagnosticMessage>,
@@ -837,6 +855,7 @@ impl Handler {
 
     /// Construct a builder at the `Fatal` level at the given `span` and with the `msg`.
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_span_fatal(
         &self,
         span: impl Into<MultiSpan>,
@@ -849,6 +868,7 @@ impl Handler {
 
     /// Construct a builder at the `Fatal` level at the given `span`, with the `msg`, and `code`.
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_span_fatal_with_code(
         &self,
         span: impl Into<MultiSpan>,
@@ -862,6 +882,7 @@ impl Handler {
 
     /// Construct a builder at the `Error` level with the `msg`.
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_fatal(&self, msg: impl Into<DiagnosticMessage>) -> DiagnosticBuilder<'_, !> {
         DiagnosticBuilder::new_fatal(self, msg)
     }
@@ -874,6 +895,7 @@ impl Handler {
 
     /// Construct a builder at the `Note` level with the `msg`.
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_note_without_error(
         &self,
         msg: impl Into<DiagnosticMessage>,
@@ -882,12 +904,14 @@ impl Handler {
     }
 
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn span_fatal(&self, span: impl Into<MultiSpan>, msg: impl Into<DiagnosticMessage>) -> ! {
         self.emit_diag_at_span(Diagnostic::new(Fatal, msg), span);
         FatalError.raise()
     }
 
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn span_fatal_with_code(
         &self,
         span: impl Into<MultiSpan>,
@@ -899,6 +923,7 @@ impl Handler {
     }
 
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn span_err(
         &self,
         span: impl Into<MultiSpan>,
@@ -908,6 +933,7 @@ impl Handler {
     }
 
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn span_err_with_code(
         &self,
         span: impl Into<MultiSpan>,
@@ -921,11 +947,13 @@ impl Handler {
     }
 
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn span_warn(&self, span: impl Into<MultiSpan>, msg: impl Into<DiagnosticMessage>) {
         self.emit_diag_at_span(Diagnostic::new(Warning(None), msg), span);
     }
 
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn span_warn_with_code(
         &self,
         span: impl Into<MultiSpan>,
@@ -954,10 +982,12 @@ impl Handler {
         self.inner.borrow_mut().delay_good_path_bug(msg)
     }
 
+    #[track_caller]
     pub fn span_bug_no_panic(&self, span: impl Into<MultiSpan>, msg: impl Into<DiagnosticMessage>) {
         self.emit_diag_at_span(Diagnostic::new(Bug, msg), span);
     }
 
+    #[track_caller]
     pub fn span_note_without_error(
         &self,
         span: impl Into<MultiSpan>,
@@ -966,6 +996,7 @@ impl Handler {
         self.emit_diag_at_span(Diagnostic::new(Note, msg), span);
     }
 
+    #[track_caller]
     pub fn span_note_diag(
         &self,
         span: Span,
@@ -1223,6 +1254,10 @@ impl HandlerInner {
         }
 
         if diagnostic.has_future_breakage() {
+            // Future breakages aren't emitted if they're Level::Allowed,
+            // but they still need to be constructed and stashed below,
+            // so they'll trigger the good-path bug check.
+            self.suppressed_expected_diag = true;
             self.future_breakage_diagnostics.push(diagnostic.clone());
         }
 
@@ -1452,6 +1487,7 @@ impl HandlerInner {
         }
     }
 
+    #[track_caller]
     fn span_bug(&mut self, sp: impl Into<MultiSpan>, msg: impl Into<DiagnosticMessage>) -> ! {
         self.emit_diag_at_span(Diagnostic::new(Bug, msg), sp);
         panic::panic_any(ExplicitBug);
diff --git a/compiler/rustc_errors/src/translation.rs b/compiler/rustc_errors/src/translation.rs
index a7737b467b75..a452fac07478 100644
--- a/compiler/rustc_errors/src/translation.rs
+++ b/compiler/rustc_errors/src/translation.rs
@@ -1,7 +1,10 @@
 use crate::snippet::Style;
 use crate::{DiagnosticArg, DiagnosticMessage, FluentBundle};
 use rustc_data_structures::sync::Lrc;
-use rustc_error_messages::FluentArgs;
+use rustc_error_messages::{
+    fluent_bundle::resolver::errors::{ReferenceKind, ResolverError},
+    FluentArgs, FluentError,
+};
 use std::borrow::Cow;
 
 /// Convert diagnostic arguments (a rustc internal type that exists to implement
@@ -102,14 +105,31 @@ pub trait Translate {
             .or_else(|| translate_with_bundle(self.fallback_fluent_bundle()))
             .map(|(translated, errs)| {
                 // Always bail out for errors with the fallback bundle.
-                assert!(
-                    errs.is_empty(),
-                    "identifier: {:?}, attr: {:?}, args: {:?}, errors: {:?}",
-                    identifier,
-                    attr,
-                    args,
-                    errs
-                );
+
+                let mut help_messages = vec![];
+
+                if !errs.is_empty() {
+                    for error in &errs {
+                        match error {
+                            FluentError::ResolverError(ResolverError::Reference(
+                                ReferenceKind::Message { id, .. },
+                            )) if args.iter().any(|(arg_id, _)| arg_id == id) => {
+                                help_messages.push(format!("Argument `{id}` exists but was not referenced correctly. Try using `{{${id}}}` instead"));
+                            }
+                            _ => {}
+                        }
+                    }
+
+                    panic!(
+                        "Encountered errors while formatting message for `{identifier}`\n\
+                        help: {}\n\
+                        attr: `{attr:?}`\n\
+                        args: `{args:?}`\n\
+                        errors: `{errs:?}`",
+                        help_messages.join("\nhelp: ")
+                    );
+                }
+
                 translated
             })
             .expect("failed to find message in primary or fallback fluent bundles")
diff --git a/compiler/rustc_expand/src/base.rs b/compiler/rustc_expand/src/base.rs
index 052ca229f012..1294f1e17d41 100644
--- a/compiler/rustc_expand/src/base.rs
+++ b/compiler/rustc_expand/src/base.rs
@@ -22,7 +22,7 @@ use rustc_span::edition::Edition;
 use rustc_span::hygiene::{AstPass, ExpnData, ExpnKind, LocalExpnId};
 use rustc_span::source_map::SourceMap;
 use rustc_span::symbol::{kw, sym, Ident, Symbol};
-use rustc_span::{BytePos, FileName, Span, DUMMY_SP};
+use rustc_span::{BytePos, FileName, RealFileName, Span, DUMMY_SP};
 use smallvec::{smallvec, SmallVec};
 
 use std::default::Default;
@@ -250,6 +250,7 @@ pub trait MultiItemModifier {
         span: Span,
         meta_item: &ast::MetaItem,
         item: Annotatable,
+        is_derive_const: bool,
     ) -> ExpandResult<Vec<Annotatable>, Annotatable>;
 }
 
@@ -263,6 +264,7 @@ where
         span: Span,
         meta_item: &ast::MetaItem,
         item: Annotatable,
+        _is_derive_const: bool,
     ) -> ExpandResult<Vec<Annotatable>, Annotatable> {
         ExpandResult::Ready(self(ecx, span, meta_item, item))
     }
@@ -873,7 +875,7 @@ impl SyntaxExtension {
 /// Error type that denotes indeterminacy.
 pub struct Indeterminate;
 
-pub type DeriveResolutions = Vec<(ast::Path, Annotatable, Option<Lrc<SyntaxExtension>>)>;
+pub type DeriveResolutions = Vec<(ast::Path, Annotatable, Option<Lrc<SyntaxExtension>>, bool)>;
 
 pub trait ResolverExpand {
     fn next_node_id(&mut self) -> NodeId;
@@ -1423,16 +1425,40 @@ fn pretty_printing_compatibility_hack(item: &Item, sess: &ParseSess) -> bool {
         if let ast::ItemKind::Enum(enum_def, _) = &item.kind {
             if let [variant] = &*enum_def.variants {
                 if variant.ident.name == sym::Input {
-                    sess.buffer_lint_with_diagnostic(
-                        &PROC_MACRO_BACK_COMPAT,
-                        item.ident.span,
-                        ast::CRATE_NODE_ID,
-                        "using `procedural-masquerade` crate",
-                        BuiltinLintDiagnostics::ProcMacroBackCompat(
-                        "The `procedural-masquerade` crate has been unnecessary since Rust 1.30.0. \
-                        Versions of this crate below 0.1.7 will eventually stop compiling.".to_string())
-                    );
-                    return true;
+                    let filename = sess.source_map().span_to_filename(item.ident.span);
+                    if let FileName::Real(RealFileName::LocalPath(path)) = filename {
+                        if let Some(c) = path
+                            .components()
+                            .flat_map(|c| c.as_os_str().to_str())
+                            .find(|c| c.starts_with("rental") || c.starts_with("allsorts-rental"))
+                        {
+                            let crate_matches = if c.starts_with("allsorts-rental") {
+                                true
+                            } else {
+                                let mut version = c.trim_start_matches("rental-").split(".");
+                                version.next() == Some("0")
+                                    && version.next() == Some("5")
+                                    && version
+                                        .next()
+                                        .and_then(|c| c.parse::<u32>().ok())
+                                        .map_or(false, |v| v < 6)
+                            };
+
+                            if crate_matches {
+                                sess.buffer_lint_with_diagnostic(
+                                        &PROC_MACRO_BACK_COMPAT,
+                                        item.ident.span,
+                                        ast::CRATE_NODE_ID,
+                                        "using an old version of `rental`",
+                                        BuiltinLintDiagnostics::ProcMacroBackCompat(
+                                        "older versions of the `rental` crate will stop compiling in future versions of Rust; \
+                                        please update to `rental` v0.5.6, or switch to one of the `rental` alternatives".to_string()
+                                        )
+                                    );
+                                return true;
+                            }
+                        }
+                    }
                 }
             }
         }
diff --git a/compiler/rustc_expand/src/config.rs b/compiler/rustc_expand/src/config.rs
index 8d4e36407486..1d2b1298a68f 100644
--- a/compiler/rustc_expand/src/config.rs
+++ b/compiler/rustc_expand/src/config.rs
@@ -469,6 +469,7 @@ impl<'a> StripUnconfigured<'a> {
     }
 
     /// If attributes are not allowed on expressions, emit an error for `attr`
+    #[instrument(level = "trace", skip(self))]
     pub(crate) fn maybe_emit_expr_attr_err(&self, attr: &Attribute) {
         if !self.features.map_or(true, |features| features.stmt_expr_attributes) {
             let mut err = feature_err(
@@ -486,9 +487,12 @@ impl<'a> StripUnconfigured<'a> {
         }
     }
 
-    pub fn configure_expr(&self, expr: &mut P<ast::Expr>) {
-        for attr in expr.attrs.iter() {
-            self.maybe_emit_expr_attr_err(attr);
+    #[instrument(level = "trace", skip(self))]
+    pub fn configure_expr(&self, expr: &mut P<ast::Expr>, method_receiver: bool) {
+        if !method_receiver {
+            for attr in expr.attrs.iter() {
+                self.maybe_emit_expr_attr_err(attr);
+            }
         }
 
         // If an expr is valid to cfg away it will have been removed by the
diff --git a/compiler/rustc_expand/src/expand.rs b/compiler/rustc_expand/src/expand.rs
index 15e9a8db3c60..3d37e2c65685 100644
--- a/compiler/rustc_expand/src/expand.rs
+++ b/compiler/rustc_expand/src/expand.rs
@@ -50,6 +50,7 @@ macro_rules! ast_fragments {
         /// Can also serve as an input and intermediate result for macro expansion operations.
         pub enum AstFragment {
             OptExpr(Option<P<ast::Expr>>),
+            MethodReceiverExpr(P<ast::Expr>),
             $($Kind($AstTy),)*
         }
 
@@ -57,6 +58,7 @@ macro_rules! ast_fragments {
         #[derive(Copy, Clone, PartialEq, Eq)]
         pub enum AstFragmentKind {
             OptExpr,
+            MethodReceiverExpr,
             $($Kind,)*
         }
 
@@ -64,6 +66,7 @@ macro_rules! ast_fragments {
             pub fn name(self) -> &'static str {
                 match self {
                     AstFragmentKind::OptExpr => "expression",
+                    AstFragmentKind::MethodReceiverExpr => "expression",
                     $(AstFragmentKind::$Kind => $kind_name,)*
                 }
             }
@@ -72,6 +75,8 @@ macro_rules! ast_fragments {
                 match self {
                     AstFragmentKind::OptExpr =>
                         result.make_expr().map(Some).map(AstFragment::OptExpr),
+                    AstFragmentKind::MethodReceiverExpr =>
+                        result.make_expr().map(AstFragment::MethodReceiverExpr),
                     $(AstFragmentKind::$Kind => result.$make_ast().map(AstFragment::$Kind),)*
                 }
             }
@@ -98,6 +103,13 @@ macro_rules! ast_fragments {
                 }
             }
 
+            pub fn make_method_receiver_expr(self) -> P<ast::Expr> {
+                match self {
+                    AstFragment::MethodReceiverExpr(expr) => expr,
+                    _ => panic!("AstFragment::make_* called on the wrong kind of fragment"),
+                }
+            }
+
             $(pub fn $make_ast(self) -> $AstTy {
                 match self {
                     AstFragment::$Kind(ast) => ast,
@@ -120,6 +132,7 @@ macro_rules! ast_fragments {
                             }
                         });
                     }
+                    AstFragment::MethodReceiverExpr(expr) => vis.visit_method_receiver_expr(expr),
                     $($(AstFragment::$Kind(ast) => vis.$mut_visit_ast(ast),)?)*
                     $($(AstFragment::$Kind(ast) =>
                         ast.flat_map_in_place(|ast| vis.$flat_map_ast_elt(ast)),)?)*
@@ -130,6 +143,7 @@ macro_rules! ast_fragments {
                 match *self {
                     AstFragment::OptExpr(Some(ref expr)) => visitor.visit_expr(expr),
                     AstFragment::OptExpr(None) => {}
+                    AstFragment::MethodReceiverExpr(ref expr) => visitor.visit_method_receiver_expr(expr),
                     $($(AstFragment::$Kind(ref ast) => visitor.$visit_ast(ast),)?)*
                     $($(AstFragment::$Kind(ref ast) => for ast_elt in &ast[..] {
                         visitor.$visit_ast_elt(ast_elt, $($args)*);
@@ -222,6 +236,7 @@ impl AstFragmentKind {
         match self {
             AstFragmentKind::OptExpr
             | AstFragmentKind::Expr
+            | AstFragmentKind::MethodReceiverExpr
             | AstFragmentKind::Stmts
             | AstFragmentKind::Ty
             | AstFragmentKind::Pat => SupportsMacroExpansion::Yes { supports_inner_attrs: false },
@@ -285,6 +300,9 @@ impl AstFragmentKind {
             AstFragmentKind::Expr => AstFragment::Expr(
                 items.next().expect("expected exactly one expression").expect_expr(),
             ),
+            AstFragmentKind::MethodReceiverExpr => AstFragment::MethodReceiverExpr(
+                items.next().expect("expected exactly one expression").expect_expr(),
+            ),
             AstFragmentKind::OptExpr => {
                 AstFragment::OptExpr(items.next().map(Annotatable::expect_expr))
             }
@@ -319,6 +337,7 @@ pub enum InvocationKind {
     },
     Derive {
         path: ast::Path,
+        is_const: bool,
         item: Annotatable,
     },
 }
@@ -460,13 +479,13 @@ impl<'a, 'b> MacroExpander<'a, 'b> {
                             derive_invocations.reserve(derives.len());
                             derives
                                 .into_iter()
-                                .map(|(path, item, _exts)| {
+                                .map(|(path, item, _exts, is_const)| {
                                     // FIXME: Consider using the derive resolutions (`_exts`)
                                     // instead of enqueuing the derives to be resolved again later.
                                     let expn_id = LocalExpnId::fresh_empty();
                                     derive_invocations.push((
                                         Invocation {
-                                            kind: InvocationKind::Derive { path, item },
+                                            kind: InvocationKind::Derive { path, item, is_const },
                                             fragment_kind,
                                             expansion_data: ExpansionData {
                                                 id: expn_id,
@@ -699,7 +718,7 @@ impl<'a, 'b> MacroExpander<'a, 'b> {
                 SyntaxExtensionKind::LegacyAttr(expander) => {
                     match validate_attr::parse_meta(&self.cx.sess.parse_sess, &attr) {
                         Ok(meta) => {
-                            let items = match expander.expand(self.cx, span, &meta, item) {
+                            let items = match expander.expand(self.cx, span, &meta, item, false) {
                                 ExpandResult::Ready(items) => items,
                                 ExpandResult::Retry(item) => {
                                     // Reassemble the original invocation for retrying.
@@ -731,19 +750,19 @@ impl<'a, 'b> MacroExpander<'a, 'b> {
                 }
                 _ => unreachable!(),
             },
-            InvocationKind::Derive { path, item } => match ext {
+            InvocationKind::Derive { path, item, is_const } => match ext {
                 SyntaxExtensionKind::Derive(expander)
                 | SyntaxExtensionKind::LegacyDerive(expander) => {
                     if let SyntaxExtensionKind::Derive(..) = ext {
                         self.gate_proc_macro_input(&item);
                     }
                     let meta = ast::MetaItem { kind: MetaItemKind::Word, span, path };
-                    let items = match expander.expand(self.cx, span, &meta, item) {
+                    let items = match expander.expand(self.cx, span, &meta, item, is_const) {
                         ExpandResult::Ready(items) => items,
                         ExpandResult::Retry(item) => {
                             // Reassemble the original invocation for retrying.
                             return ExpandResult::Retry(Invocation {
-                                kind: InvocationKind::Derive { path: meta.path, item },
+                                kind: InvocationKind::Derive { path: meta.path, item, is_const },
                                 ..invoc
                             });
                         }
@@ -893,6 +912,7 @@ pub fn parse_ast_fragment<'a>(
             AstFragment::Stmts(stmts)
         }
         AstFragmentKind::Expr => AstFragment::Expr(this.parse_expr()?),
+        AstFragmentKind::MethodReceiverExpr => AstFragment::MethodReceiverExpr(this.parse_expr()?),
         AstFragmentKind::OptExpr => {
             if this.token != token::Eof {
                 AstFragment::OptExpr(Some(this.parse_expr()?))
@@ -1477,6 +1497,42 @@ impl InvocationCollectorNode for AstNodeWrapper<P<ast::Expr>, OptExprTag> {
     }
 }
 
+/// This struct is a hack to workaround unstable of `stmt_expr_attributes`.
+/// It can be removed once that feature is stabilized.
+struct MethodReceiverTag;
+impl DummyAstNode for MethodReceiverTag {
+    fn dummy() -> MethodReceiverTag {
+        MethodReceiverTag
+    }
+}
+impl InvocationCollectorNode for AstNodeWrapper<P<ast::Expr>, MethodReceiverTag> {
+    type OutputTy = Self;
+    type AttrsTy = ast::AttrVec;
+    const KIND: AstFragmentKind = AstFragmentKind::MethodReceiverExpr;
+    fn descr() -> &'static str {
+        "an expression"
+    }
+    fn to_annotatable(self) -> Annotatable {
+        Annotatable::Expr(self.wrapped)
+    }
+    fn fragment_to_output(fragment: AstFragment) -> Self::OutputTy {
+        AstNodeWrapper::new(fragment.make_method_receiver_expr(), MethodReceiverTag)
+    }
+    fn noop_visit<V: MutVisitor>(&mut self, visitor: &mut V) {
+        noop_visit_expr(&mut self.wrapped, visitor)
+    }
+    fn is_mac_call(&self) -> bool {
+        matches!(self.wrapped.kind, ast::ExprKind::MacCall(..))
+    }
+    fn take_mac_call(self) -> (P<ast::MacCall>, Self::AttrsTy, AddSemicolon) {
+        let node = self.wrapped.into_inner();
+        match node.kind {
+            ExprKind::MacCall(mac) => (mac, node.attrs, AddSemicolon::No),
+            _ => unreachable!(),
+        }
+    }
+}
+
 struct InvocationCollector<'a, 'b> {
     cx: &'a mut ExtCtxt<'b>,
     invocations: Vec<(Invocation, Option<Lrc<SyntaxExtension>>)>,
@@ -1840,6 +1896,14 @@ impl<'a, 'b> MutVisitor for InvocationCollector<'a, 'b> {
         self.visit_node(node)
     }
 
+    fn visit_method_receiver_expr(&mut self, node: &mut P<ast::Expr>) {
+        visit_clobber(node, |node| {
+            let mut wrapper = AstNodeWrapper::new(node, MethodReceiverTag);
+            self.visit_node(&mut wrapper);
+            wrapper.wrapped
+        })
+    }
+
     fn filter_map_expr(&mut self, node: P<ast::Expr>) -> Option<P<ast::Expr>> {
         self.flat_map_node(AstNodeWrapper::new(node, OptExprTag))
     }
diff --git a/compiler/rustc_expand/src/mbe.rs b/compiler/rustc_expand/src/mbe.rs
index f42576b16f52..63bafd7b046f 100644
--- a/compiler/rustc_expand/src/mbe.rs
+++ b/compiler/rustc_expand/src/mbe.rs
@@ -52,7 +52,7 @@ impl KleeneToken {
 /// A Kleene-style [repetition operator](https://en.wikipedia.org/wiki/Kleene_star)
 /// for token sequences.
 #[derive(Clone, PartialEq, Encodable, Decodable, Debug, Copy)]
-enum KleeneOp {
+pub(crate) enum KleeneOp {
     /// Kleene star (`*`) for zero or more repetitions
     ZeroOrMore,
     /// Kleene plus (`+`) for one or more repetitions
diff --git a/compiler/rustc_expand/src/mbe/macro_parser.rs b/compiler/rustc_expand/src/mbe/macro_parser.rs
index c8bdc39311c6..d161868edce7 100644
--- a/compiler/rustc_expand/src/mbe/macro_parser.rs
+++ b/compiler/rustc_expand/src/mbe/macro_parser.rs
@@ -73,19 +73,21 @@
 pub(crate) use NamedMatch::*;
 pub(crate) use ParseResult::*;
 
-use crate::mbe::{KleeneOp, TokenTree};
+use crate::mbe::{macro_rules::Tracker, KleeneOp, TokenTree};
 
 use rustc_ast::token::{self, DocComment, Nonterminal, NonterminalKind, Token};
-use rustc_lint_defs::pluralize;
-use rustc_parse::parser::{NtOrTt, Parser};
-use rustc_span::symbol::MacroRulesNormalizedIdent;
-use rustc_span::Span;
-
+use rustc_ast_pretty::pprust;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sync::Lrc;
+use rustc_errors::ErrorGuaranteed;
+use rustc_lint_defs::pluralize;
+use rustc_parse::parser::{NtOrTt, Parser};
 use rustc_span::symbol::Ident;
+use rustc_span::symbol::MacroRulesNormalizedIdent;
+use rustc_span::Span;
 use std::borrow::Cow;
 use std::collections::hash_map::Entry::{Occupied, Vacant};
+use std::fmt::Display;
 
 /// A unit within a matcher that a `MatcherPos` can refer to. Similar to (and derived from)
 /// `mbe::TokenTree`, but designed specifically for fast and easy traversal during matching.
@@ -96,7 +98,8 @@ use std::collections::hash_map::Entry::{Occupied, Vacant};
 ///
 /// This means a matcher can be represented by `&[MatcherLoc]`, and traversal mostly involves
 /// simply incrementing the current matcher position index by one.
-pub(super) enum MatcherLoc {
+#[derive(Debug, PartialEq, Clone)]
+pub(crate) enum MatcherLoc {
     Token {
         token: Token,
     },
@@ -128,6 +131,46 @@ pub(super) enum MatcherLoc {
     Eof,
 }
 
+impl MatcherLoc {
+    pub(super) fn span(&self) -> Option<Span> {
+        match self {
+            MatcherLoc::Token { token } => Some(token.span),
+            MatcherLoc::Delimited => None,
+            MatcherLoc::Sequence { .. } => None,
+            MatcherLoc::SequenceKleeneOpNoSep { .. } => None,
+            MatcherLoc::SequenceSep { .. } => None,
+            MatcherLoc::SequenceKleeneOpAfterSep { .. } => None,
+            MatcherLoc::MetaVarDecl { span, .. } => Some(*span),
+            MatcherLoc::Eof => None,
+        }
+    }
+}
+
+impl Display for MatcherLoc {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            MatcherLoc::Token { token } | MatcherLoc::SequenceSep { separator: token } => {
+                write!(f, "`{}`", pprust::token_to_string(token))
+            }
+            MatcherLoc::MetaVarDecl { bind, kind, .. } => {
+                write!(f, "meta-variable `${bind}")?;
+                if let Some(kind) = kind {
+                    write!(f, ":{}", kind)?;
+                }
+                write!(f, "`")?;
+                Ok(())
+            }
+            MatcherLoc::Eof => f.write_str("end of macro"),
+
+            // These are not printed in the diagnostic
+            MatcherLoc::Delimited => f.write_str("delimiter"),
+            MatcherLoc::Sequence { .. } => f.write_str("sequence start"),
+            MatcherLoc::SequenceKleeneOpNoSep { .. } => f.write_str("sequence end"),
+            MatcherLoc::SequenceKleeneOpAfterSep { .. } => f.write_str("sequence end"),
+        }
+    }
+}
+
 pub(super) fn compute_locs(matcher: &[TokenTree]) -> Vec<MatcherLoc> {
     fn inner(
         tts: &[TokenTree],
@@ -270,13 +313,17 @@ pub(crate) enum ParseResult<T> {
     Failure(Token, &'static str),
     /// Fatal error (malformed macro?). Abort compilation.
     Error(rustc_span::Span, String),
-    ErrorReported,
+    ErrorReported(ErrorGuaranteed),
 }
 
 /// A `ParseResult` where the `Success` variant contains a mapping of
 /// `MacroRulesNormalizedIdent`s to `NamedMatch`es. This represents the mapping
 /// of metavars to the token trees they bind to.
-pub(crate) type NamedParseResult = ParseResult<FxHashMap<MacroRulesNormalizedIdent, NamedMatch>>;
+pub(crate) type NamedParseResult = ParseResult<NamedMatches>;
+
+/// Contains a mapping of `MacroRulesNormalizedIdent`s to `NamedMatch`es.
+/// This represents the mapping of metavars to the token trees they bind to.
+pub(crate) type NamedMatches = FxHashMap<MacroRulesNormalizedIdent, NamedMatch>;
 
 /// Count how many metavars declarations are in `matcher`.
 pub(super) fn count_metavar_decls(matcher: &[TokenTree]) -> usize {
@@ -393,6 +440,10 @@ impl TtParser {
         }
     }
 
+    pub(super) fn has_no_remaining_items_for_step(&self) -> bool {
+        self.cur_mps.is_empty()
+    }
+
     /// Process the matcher positions of `cur_mps` until it is empty. In the process, this will
     /// produce more mps in `next_mps` and `bb_mps`.
     ///
@@ -400,17 +451,21 @@ impl TtParser {
     ///
     /// `Some(result)` if everything is finished, `None` otherwise. Note that matches are kept
     /// track of through the mps generated.
-    fn parse_tt_inner(
+    fn parse_tt_inner<'matcher, T: Tracker<'matcher>>(
         &mut self,
-        matcher: &[MatcherLoc],
+        matcher: &'matcher [MatcherLoc],
         token: &Token,
+        track: &mut T,
     ) -> Option<NamedParseResult> {
         // Matcher positions that would be valid if the macro invocation was over now. Only
         // modified if `token == Eof`.
         let mut eof_mps = EofMatcherPositions::None;
 
         while let Some(mut mp) = self.cur_mps.pop() {
-            match &matcher[mp.idx] {
+            let matcher_loc = &matcher[mp.idx];
+            track.before_match_loc(self, matcher_loc);
+
+            match matcher_loc {
                 MatcherLoc::Token { token: t } => {
                     // If it's a doc comment, we just ignore it and move on to the next tt in the
                     // matcher. This is a bug, but #95267 showed that existing programs rely on
@@ -450,7 +505,7 @@ impl TtParser {
                         // Try zero matches of this sequence, by skipping over it.
                         self.cur_mps.push(MatcherPos {
                             idx: idx_first_after,
-                            matches: mp.matches.clone(), // a cheap clone
+                            matches: Lrc::clone(&mp.matches),
                         });
                     }
 
@@ -463,8 +518,8 @@ impl TtParser {
                     // sequence. If that's not possible, `ending_mp` will fail quietly when it is
                     // processed next time around the loop.
                     let ending_mp = MatcherPos {
-                        idx: mp.idx + 1,             // +1 skips the Kleene op
-                        matches: mp.matches.clone(), // a cheap clone
+                        idx: mp.idx + 1, // +1 skips the Kleene op
+                        matches: Lrc::clone(&mp.matches),
                     };
                     self.cur_mps.push(ending_mp);
 
@@ -479,8 +534,8 @@ impl TtParser {
                     // separator yet. Try ending the sequence. If that's not possible, `ending_mp`
                     // will fail quietly when it is processed next time around the loop.
                     let ending_mp = MatcherPos {
-                        idx: mp.idx + 2,             // +2 skips the separator and the Kleene op
-                        matches: mp.matches.clone(), // a cheap clone
+                        idx: mp.idx + 2, // +2 skips the separator and the Kleene op
+                        matches: Lrc::clone(&mp.matches),
                     };
                     self.cur_mps.push(ending_mp);
 
@@ -552,10 +607,11 @@ impl TtParser {
     }
 
     /// Match the token stream from `parser` against `matcher`.
-    pub(super) fn parse_tt(
+    pub(super) fn parse_tt<'matcher, T: Tracker<'matcher>>(
         &mut self,
         parser: &mut Cow<'_, Parser<'_>>,
-        matcher: &[MatcherLoc],
+        matcher: &'matcher [MatcherLoc],
+        track: &mut T,
     ) -> NamedParseResult {
         // A queue of possible matcher positions. We initialize it with the matcher position in
         // which the "dot" is before the first token of the first token tree in `matcher`.
@@ -571,7 +627,8 @@ impl TtParser {
 
             // Process `cur_mps` until either we have finished the input or we need to get some
             // parsing from the black-box parser done.
-            if let Some(res) = self.parse_tt_inner(matcher, &parser.token) {
+            let res = self.parse_tt_inner(matcher, &parser.token, track);
+            if let Some(res) = res {
                 return res;
             }
 
@@ -612,14 +669,14 @@ impl TtParser {
                         // edition-specific matching behavior for non-terminals.
                         let nt = match parser.to_mut().parse_nonterminal(kind) {
                             Err(mut err) => {
-                                err.span_label(
+                                let guarantee = err.span_label(
                                     span,
                                     format!(
                                         "while parsing argument for this `{kind}` macro fragment"
                                     ),
                                 )
                                 .emit();
-                                return ErrorReported;
+                                return ErrorReported(guarantee);
                             }
                             Ok(nt) => nt,
                         };
diff --git a/compiler/rustc_expand/src/mbe/macro_rules.rs b/compiler/rustc_expand/src/mbe/macro_rules.rs
index 1e268542bcd9..182fbe36919d 100644
--- a/compiler/rustc_expand/src/mbe/macro_rules.rs
+++ b/compiler/rustc_expand/src/mbe/macro_rules.rs
@@ -14,7 +14,9 @@ use rustc_ast::{NodeId, DUMMY_NODE_ID};
 use rustc_ast_pretty::pprust;
 use rustc_attr::{self as attr, TransparencyError};
 use rustc_data_structures::fx::{FxHashMap, FxIndexMap};
-use rustc_errors::{Applicability, Diagnostic, DiagnosticBuilder, DiagnosticMessage};
+use rustc_errors::{
+    Applicability, Diagnostic, DiagnosticBuilder, DiagnosticMessage, ErrorGuaranteed,
+};
 use rustc_feature::Features;
 use rustc_lint_defs::builtin::{
     RUST_2021_INCOMPATIBLE_OR_PATTERNS, SEMICOLON_IN_EXPRESSIONS_FROM_MACROS,
@@ -33,6 +35,8 @@ use std::borrow::Cow;
 use std::collections::hash_map::Entry;
 use std::{mem, slice};
 
+use super::macro_parser::{NamedMatches, NamedParseResult};
+
 pub(crate) struct ParserAnyMacro<'a> {
     parser: Parser<'a>,
 
@@ -205,8 +209,32 @@ fn trace_macros_note(cx_expansions: &mut FxIndexMap<Span, Vec<String>>, sp: Span
     cx_expansions.entry(sp).or_default().push(message);
 }
 
+pub(super) trait Tracker<'matcher> {
+    /// This is called before trying to match next MatcherLoc on the current token.
+    fn before_match_loc(&mut self, parser: &TtParser, matcher: &'matcher MatcherLoc);
+
+    /// This is called after an arm has been parsed, either successfully or unsuccessfully. When this is called,
+    /// `before_match_loc` was called at least once (with a `MatcherLoc::Eof`).
+    fn after_arm(&mut self, result: &NamedParseResult);
+
+    /// For tracing.
+    fn description() -> &'static str;
+}
+
+/// A noop tracker that is used in the hot path of the expansion, has zero overhead thanks to monomorphization.
+struct NoopTracker;
+
+impl<'matcher> Tracker<'matcher> for NoopTracker {
+    fn before_match_loc(&mut self, _: &TtParser, _: &'matcher MatcherLoc) {}
+    fn after_arm(&mut self, _: &NamedParseResult) {}
+    fn description() -> &'static str {
+        "none"
+    }
+}
+
 /// Expands the rules based macro defined by `lhses` and `rhses` for a given
 /// input `arg`.
+#[instrument(skip(cx, transparency, arg, lhses, rhses))]
 fn expand_macro<'cx>(
     cx: &'cx mut ExtCtxt<'_>,
     sp: Span,
@@ -228,9 +256,207 @@ fn expand_macro<'cx>(
         trace_macros_note(&mut cx.expansions, sp, msg);
     }
 
-    // Which arm's failure should we report? (the one furthest along)
-    let mut best_failure: Option<(Token, &str)> = None;
+    // Track nothing for the best performance.
+    let try_success_result = try_match_macro(sess, name, &arg, lhses, &mut NoopTracker);
 
+    match try_success_result {
+        Ok((i, named_matches)) => {
+            let (rhs, rhs_span): (&mbe::Delimited, DelimSpan) = match &rhses[i] {
+                mbe::TokenTree::Delimited(span, delimited) => (&delimited, *span),
+                _ => cx.span_bug(sp, "malformed macro rhs"),
+            };
+            let arm_span = rhses[i].span();
+
+            let rhs_spans = rhs.tts.iter().map(|t| t.span()).collect::<Vec<_>>();
+            // rhs has holes ( `$id` and `$(...)` that need filled)
+            let mut tts = match transcribe(cx, &named_matches, &rhs, rhs_span, transparency) {
+                Ok(tts) => tts,
+                Err(mut err) => {
+                    err.emit();
+                    return DummyResult::any(arm_span);
+                }
+            };
+
+            // Replace all the tokens for the corresponding positions in the macro, to maintain
+            // proper positions in error reporting, while maintaining the macro_backtrace.
+            if rhs_spans.len() == tts.len() {
+                tts = tts.map_enumerated(|i, tt| {
+                    let mut tt = tt.clone();
+                    let mut sp = rhs_spans[i];
+                    sp = sp.with_ctxt(tt.span().ctxt());
+                    tt.set_span(sp);
+                    tt
+                });
+            }
+
+            if cx.trace_macros() {
+                let msg = format!("to `{}`", pprust::tts_to_string(&tts));
+                trace_macros_note(&mut cx.expansions, sp, msg);
+            }
+
+            let mut p = Parser::new(sess, tts, false, None);
+            p.last_type_ascription = cx.current_expansion.prior_type_ascription;
+
+            if is_local {
+                cx.resolver.record_macro_rule_usage(node_id, i);
+            }
+
+            // Let the context choose how to interpret the result.
+            // Weird, but useful for X-macros.
+            return Box::new(ParserAnyMacro {
+                parser: p,
+
+                // Pass along the original expansion site and the name of the macro
+                // so we can print a useful error message if the parse of the expanded
+                // macro leaves unparsed tokens.
+                site_span: sp,
+                macro_ident: name,
+                lint_node_id: cx.current_expansion.lint_node_id,
+                is_trailing_mac: cx.current_expansion.is_trailing_mac,
+                arm_span,
+                is_local,
+            });
+        }
+        Err(CanRetry::No(_)) => {
+            debug!("Will not retry matching as an error was emitted already");
+            return DummyResult::any(sp);
+        }
+        Err(CanRetry::Yes) => {
+            // Retry and emit a better error below.
+        }
+    }
+
+    // An error occurred, try the expansion again, tracking the expansion closely for better diagnostics.
+    let mut tracker = CollectTrackerAndEmitter::new(cx, sp);
+
+    let try_success_result = try_match_macro(sess, name, &arg, lhses, &mut tracker);
+    assert!(try_success_result.is_err(), "Macro matching returned a success on the second try");
+
+    if let Some(result) = tracker.result {
+        // An irrecoverable error occurred and has been emitted.
+        return result;
+    }
+
+    let Some((token, label, remaining_matcher)) = tracker.best_failure else {
+        return tracker.result.expect("must have encountered Error or ErrorReported");
+    };
+
+    let span = token.span.substitute_dummy(sp);
+
+    let mut err = cx.struct_span_err(span, &parse_failure_msg(&token));
+    err.span_label(span, label);
+    if !def_span.is_dummy() && !cx.source_map().is_imported(def_span) {
+        err.span_label(cx.source_map().guess_head_span(def_span), "when calling this macro");
+    }
+
+    annotate_doc_comment(&mut err, sess.source_map(), span);
+
+    if let Some(span) = remaining_matcher.span() {
+        err.span_note(span, format!("while trying to match {remaining_matcher}"));
+    } else {
+        err.note(format!("while trying to match {remaining_matcher}"));
+    }
+
+    // Check whether there's a missing comma in this macro call, like `println!("{}" a);`
+    if let Some((arg, comma_span)) = arg.add_comma() {
+        for lhs in lhses {
+            let parser = parser_from_cx(sess, arg.clone());
+            let mut tt_parser = TtParser::new(name);
+
+            if let Success(_) =
+                tt_parser.parse_tt(&mut Cow::Borrowed(&parser), lhs, &mut NoopTracker)
+            {
+                if comma_span.is_dummy() {
+                    err.note("you might be missing a comma");
+                } else {
+                    err.span_suggestion_short(
+                        comma_span,
+                        "missing comma here",
+                        ", ",
+                        Applicability::MachineApplicable,
+                    );
+                }
+            }
+        }
+    }
+    err.emit();
+    cx.trace_macros_diag();
+    DummyResult::any(sp)
+}
+
+/// The tracker used for the slow error path that collects useful info for diagnostics.
+struct CollectTrackerAndEmitter<'a, 'cx, 'matcher> {
+    cx: &'a mut ExtCtxt<'cx>,
+    remaining_matcher: Option<&'matcher MatcherLoc>,
+    /// Which arm's failure should we report? (the one furthest along)
+    best_failure: Option<(Token, &'static str, MatcherLoc)>,
+    root_span: Span,
+    result: Option<Box<dyn MacResult + 'cx>>,
+}
+
+impl<'a, 'cx, 'matcher> Tracker<'matcher> for CollectTrackerAndEmitter<'a, 'cx, 'matcher> {
+    fn before_match_loc(&mut self, parser: &TtParser, matcher: &'matcher MatcherLoc) {
+        if self.remaining_matcher.is_none()
+            || (parser.has_no_remaining_items_for_step() && *matcher != MatcherLoc::Eof)
+        {
+            self.remaining_matcher = Some(matcher);
+        }
+    }
+
+    fn after_arm(&mut self, result: &NamedParseResult) {
+        match result {
+            Success(_) => {
+                unreachable!("should not collect detailed info for successful macro match");
+            }
+            Failure(token, msg) => match self.best_failure {
+                Some((ref best_token, _, _)) if best_token.span.lo() >= token.span.lo() => {}
+                _ => {
+                    self.best_failure = Some((
+                        token.clone(),
+                        msg,
+                        self.remaining_matcher
+                            .expect("must have collected matcher already")
+                            .clone(),
+                    ))
+                }
+            },
+            Error(err_sp, msg) => {
+                let span = err_sp.substitute_dummy(self.root_span);
+                self.cx.struct_span_err(span, msg).emit();
+                self.result = Some(DummyResult::any(span));
+            }
+            ErrorReported(_) => self.result = Some(DummyResult::any(self.root_span)),
+        }
+    }
+
+    fn description() -> &'static str {
+        "detailed"
+    }
+}
+
+impl<'a, 'cx> CollectTrackerAndEmitter<'a, 'cx, '_> {
+    fn new(cx: &'a mut ExtCtxt<'cx>, root_span: Span) -> Self {
+        Self { cx, remaining_matcher: None, best_failure: None, root_span, result: None }
+    }
+}
+
+enum CanRetry {
+    Yes,
+    /// We are not allowed to retry macro expansion as a fatal error has been emitted already.
+    No(ErrorGuaranteed),
+}
+
+/// Try expanding the macro. Returns the index of the successful arm and its named_matches if it was successful,
+/// and nothing if it failed. On failure, it's the callers job to use `track` accordingly to record all errors
+/// correctly.
+#[instrument(level = "debug", skip(sess, arg, lhses, track), fields(tracking = %T::description()))]
+fn try_match_macro<'matcher, T: Tracker<'matcher>>(
+    sess: &ParseSess,
+    name: Ident,
+    arg: &TokenStream,
+    lhses: &'matcher [Vec<MatcherLoc>],
+    track: &mut T,
+) -> Result<(usize, NamedMatches), CanRetry> {
     // We create a base parser that can be used for the "black box" parts.
     // Every iteration needs a fresh copy of that parser. However, the parser
     // is not mutated on many of the iterations, particularly when dealing with
@@ -250,126 +476,54 @@ fn expand_macro<'cx>(
     // hacky, but speeds up the `html5ever` benchmark significantly. (Issue
     // 68836 suggests a more comprehensive but more complex change to deal with
     // this situation.)
+    // FIXME(Nilstrieb): Stop recovery from happening on this parser and retry later with recovery if the macro failed to match.
     let parser = parser_from_cx(sess, arg.clone());
-
     // Try each arm's matchers.
     let mut tt_parser = TtParser::new(name);
     for (i, lhs) in lhses.iter().enumerate() {
+        let _tracing_span = trace_span!("Matching arm", %i);
+
         // Take a snapshot of the state of pre-expansion gating at this point.
         // This is used so that if a matcher is not `Success(..)`ful,
         // then the spans which became gated when parsing the unsuccessful matcher
         // are not recorded. On the first `Success(..)`ful matcher, the spans are merged.
         let mut gated_spans_snapshot = mem::take(&mut *sess.gated_spans.spans.borrow_mut());
 
-        match tt_parser.parse_tt(&mut Cow::Borrowed(&parser), lhs) {
+        let result = tt_parser.parse_tt(&mut Cow::Borrowed(&parser), lhs, track);
+
+        track.after_arm(&result);
+
+        match result {
             Success(named_matches) => {
+                debug!("Parsed arm successfully");
                 // The matcher was `Success(..)`ful.
                 // Merge the gated spans from parsing the matcher with the pre-existing ones.
                 sess.gated_spans.merge(gated_spans_snapshot);
 
-                let (rhs, rhs_span): (&mbe::Delimited, DelimSpan) = match &rhses[i] {
-                    mbe::TokenTree::Delimited(span, delimited) => (&delimited, *span),
-                    _ => cx.span_bug(sp, "malformed macro rhs"),
-                };
-                let arm_span = rhses[i].span();
-
-                let rhs_spans = rhs.tts.iter().map(|t| t.span()).collect::<Vec<_>>();
-                // rhs has holes ( `$id` and `$(...)` that need filled)
-                let mut tts = match transcribe(cx, &named_matches, &rhs, rhs_span, transparency) {
-                    Ok(tts) => tts,
-                    Err(mut err) => {
-                        err.emit();
-                        return DummyResult::any(arm_span);
-                    }
-                };
-
-                // Replace all the tokens for the corresponding positions in the macro, to maintain
-                // proper positions in error reporting, while maintaining the macro_backtrace.
-                if rhs_spans.len() == tts.len() {
-                    tts = tts.map_enumerated(|i, tt| {
-                        let mut tt = tt.clone();
-                        let mut sp = rhs_spans[i];
-                        sp = sp.with_ctxt(tt.span().ctxt());
-                        tt.set_span(sp);
-                        tt
-                    });
-                }
-
-                if cx.trace_macros() {
-                    let msg = format!("to `{}`", pprust::tts_to_string(&tts));
-                    trace_macros_note(&mut cx.expansions, sp, msg);
-                }
-
-                let mut p = Parser::new(sess, tts, false, None);
-                p.last_type_ascription = cx.current_expansion.prior_type_ascription;
-
-                if is_local {
-                    cx.resolver.record_macro_rule_usage(node_id, i);
-                }
-
-                // Let the context choose how to interpret the result.
-                // Weird, but useful for X-macros.
-                return Box::new(ParserAnyMacro {
-                    parser: p,
-
-                    // Pass along the original expansion site and the name of the macro
-                    // so we can print a useful error message if the parse of the expanded
-                    // macro leaves unparsed tokens.
-                    site_span: sp,
-                    macro_ident: name,
-                    lint_node_id: cx.current_expansion.lint_node_id,
-                    is_trailing_mac: cx.current_expansion.is_trailing_mac,
-                    arm_span,
-                    is_local,
-                });
+                return Ok((i, named_matches));
             }
-            Failure(token, msg) => match best_failure {
-                Some((ref best_token, _)) if best_token.span.lo() >= token.span.lo() => {}
-                _ => best_failure = Some((token, msg)),
-            },
-            Error(err_sp, ref msg) => {
-                let span = err_sp.substitute_dummy(sp);
-                cx.struct_span_err(span, &msg).emit();
-                return DummyResult::any(span);
+            Failure(_, _) => {
+                trace!("Failed to match arm, trying the next one");
+                // Try the next arm.
+            }
+            Error(_, _) => {
+                debug!("Fatal error occurred during matching");
+                // We haven't emitted an error yet, so we can retry.
+                return Err(CanRetry::Yes);
+            }
+            ErrorReported(guarantee) => {
+                debug!("Fatal error occurred and was reported during matching");
+                // An error has been reported already, we cannot retry as that would cause duplicate errors.
+                return Err(CanRetry::No(guarantee));
             }
-            ErrorReported => return DummyResult::any(sp),
         }
 
         // The matcher was not `Success(..)`ful.
         // Restore to the state before snapshotting and maybe try again.
         mem::swap(&mut gated_spans_snapshot, &mut sess.gated_spans.spans.borrow_mut());
     }
-    drop(parser);
 
-    let (token, label) = best_failure.expect("ran no matchers");
-    let span = token.span.substitute_dummy(sp);
-    let mut err = cx.struct_span_err(span, &parse_failure_msg(&token));
-    err.span_label(span, label);
-    if !def_span.is_dummy() && !cx.source_map().is_imported(def_span) {
-        err.span_label(cx.source_map().guess_head_span(def_span), "when calling this macro");
-    }
-    annotate_doc_comment(&mut err, sess.source_map(), span);
-    // Check whether there's a missing comma in this macro call, like `println!("{}" a);`
-    if let Some((arg, comma_span)) = arg.add_comma() {
-        for lhs in lhses {
-            let parser = parser_from_cx(sess, arg.clone());
-            if let Success(_) = tt_parser.parse_tt(&mut Cow::Borrowed(&parser), lhs) {
-                if comma_span.is_dummy() {
-                    err.note("you might be missing a comma");
-                } else {
-                    err.span_suggestion_short(
-                        comma_span,
-                        "missing comma here",
-                        ", ",
-                        Applicability::MachineApplicable,
-                    );
-                }
-            }
-        }
-    }
-    err.emit();
-    cx.trace_macros_diag();
-    DummyResult::any(sp)
+    Err(CanRetry::Yes)
 }
 
 // Note that macro-by-example's input is also matched against a token tree:
@@ -451,28 +605,29 @@ pub fn compile_declarative_macro(
     let parser = Parser::new(&sess.parse_sess, body, true, rustc_parse::MACRO_ARGUMENTS);
     let mut tt_parser =
         TtParser::new(Ident::with_dummy_span(if macro_rules { kw::MacroRules } else { kw::Macro }));
-    let argument_map = match tt_parser.parse_tt(&mut Cow::Borrowed(&parser), &argument_gram) {
-        Success(m) => m,
-        Failure(token, msg) => {
-            let s = parse_failure_msg(&token);
-            let sp = token.span.substitute_dummy(def.span);
-            let mut err = sess.parse_sess.span_diagnostic.struct_span_err(sp, &s);
-            err.span_label(sp, msg);
-            annotate_doc_comment(&mut err, sess.source_map(), sp);
-            err.emit();
-            return dummy_syn_ext();
-        }
-        Error(sp, msg) => {
-            sess.parse_sess
-                .span_diagnostic
-                .struct_span_err(sp.substitute_dummy(def.span), &msg)
-                .emit();
-            return dummy_syn_ext();
-        }
-        ErrorReported => {
-            return dummy_syn_ext();
-        }
-    };
+    let argument_map =
+        match tt_parser.parse_tt(&mut Cow::Owned(parser), &argument_gram, &mut NoopTracker) {
+            Success(m) => m,
+            Failure(token, msg) => {
+                let s = parse_failure_msg(&token);
+                let sp = token.span.substitute_dummy(def.span);
+                let mut err = sess.parse_sess.span_diagnostic.struct_span_err(sp, &s);
+                err.span_label(sp, msg);
+                annotate_doc_comment(&mut err, sess.source_map(), sp);
+                err.emit();
+                return dummy_syn_ext();
+            }
+            Error(sp, msg) => {
+                sess.parse_sess
+                    .span_diagnostic
+                    .struct_span_err(sp.substitute_dummy(def.span), &msg)
+                    .emit();
+                return dummy_syn_ext();
+            }
+            ErrorReported(_) => {
+                return dummy_syn_ext();
+            }
+        };
 
     let mut valid = true;
 
diff --git a/compiler/rustc_expand/src/placeholders.rs b/compiler/rustc_expand/src/placeholders.rs
index 3b0d5ddb97b4..faaf3b3fea58 100644
--- a/compiler/rustc_expand/src/placeholders.rs
+++ b/compiler/rustc_expand/src/placeholders.rs
@@ -55,6 +55,7 @@ pub fn placeholder(
         }),
         AstFragmentKind::Expr => AstFragment::Expr(expr_placeholder()),
         AstFragmentKind::OptExpr => AstFragment::OptExpr(Some(expr_placeholder())),
+        AstFragmentKind::MethodReceiverExpr => AstFragment::MethodReceiverExpr(expr_placeholder()),
         AstFragmentKind::Items => AstFragment::Items(smallvec![P(ast::Item {
             id,
             span,
@@ -296,6 +297,13 @@ impl MutVisitor for PlaceholderExpander {
         }
     }
 
+    fn visit_method_receiver_expr(&mut self, expr: &mut P<ast::Expr>) {
+        match expr.kind {
+            ast::ExprKind::MacCall(_) => *expr = self.remove(expr.id).make_method_receiver_expr(),
+            _ => noop_visit_expr(expr, self),
+        }
+    }
+
     fn filter_map_expr(&mut self, expr: P<ast::Expr>) -> Option<P<ast::Expr>> {
         match expr.kind {
             ast::ExprKind::MacCall(_) => self.remove(expr.id).make_opt_expr(),
diff --git a/compiler/rustc_expand/src/proc_macro.rs b/compiler/rustc_expand/src/proc_macro.rs
index 1a2ab9d190eb..e9a691920689 100644
--- a/compiler/rustc_expand/src/proc_macro.rs
+++ b/compiler/rustc_expand/src/proc_macro.rs
@@ -112,6 +112,7 @@ impl MultiItemModifier for DeriveProcMacro {
         span: Span,
         _meta_item: &ast::MetaItem,
         item: Annotatable,
+        _is_derive_const: bool,
     ) -> ExpandResult<Vec<Annotatable>, Annotatable> {
         // We need special handling for statement items
         // (e.g. `fn foo() { #[derive(Debug)] struct Bar; }`)
diff --git a/compiler/rustc_expand/src/proc_macro_server.rs b/compiler/rustc_expand/src/proc_macro_server.rs
index cc2858d3f73a..a929f6cb0a5d 100644
--- a/compiler/rustc_expand/src/proc_macro_server.rs
+++ b/compiler/rustc_expand/src/proc_macro_server.rs
@@ -525,6 +525,13 @@ impl server::TokenStream for Rustc<'_, '_> {
             ast::ExprKind::Lit(l) => {
                 Ok(tokenstream::TokenStream::token_alone(token::Literal(l.token_lit), l.span))
             }
+            ast::ExprKind::IncludedBytes(bytes) => {
+                let lit = ast::Lit::from_included_bytes(bytes, expr.span);
+                Ok(tokenstream::TokenStream::token_alone(
+                    token::TokenKind::Literal(lit.token_lit),
+                    expr.span,
+                ))
+            }
             ast::ExprKind::Unary(ast::UnOp::Neg, e) => match &e.kind {
                 ast::ExprKind::Lit(l) => match l.token_lit {
                     token::Lit { kind: token::Integer | token::Float, .. } => {
diff --git a/compiler/rustc_expand/src/tests.rs b/compiler/rustc_expand/src/tests.rs
index e44f06081963..d82a7a54030c 100644
--- a/compiler/rustc_expand/src/tests.rs
+++ b/compiler/rustc_expand/src/tests.rs
@@ -151,6 +151,7 @@ fn test_harness(file_text: &str, span_labels: Vec<SpanLabel>, expected_output: &
             false,
             None,
             false,
+            false,
         );
         let handler = Handler::with_emitter(true, None, Box::new(emitter));
         handler.span_err(msp, "foo");
diff --git a/compiler/rustc_feature/src/accepted.rs b/compiler/rustc_feature/src/accepted.rs
index 54bf5a2c34b8..1646727a1c85 100644
--- a/compiler/rustc_feature/src/accepted.rs
+++ b/compiler/rustc_feature/src/accepted.rs
@@ -53,8 +53,10 @@ declare_features! (
     (accepted, abi_sysv64, "1.24.0", Some(36167), None),
     /// Allows using ADX intrinsics from `core::arch::{x86, x86_64}`.
     (accepted, adx_target_feature, "1.61.0", Some(44839), None),
+    /// Allows explicit discriminants on non-unit enum variants.
+    (accepted, arbitrary_enum_discriminant, "1.66.0", Some(60553), None),
     /// Allows using `sym` operands in inline assembly.
-    (accepted, asm_sym, "CURRENT_RUSTC_VERSION", Some(93333), None),
+    (accepted, asm_sym, "1.66.0", Some(93333), None),
     /// Allows the definition of associated constants in `trait` or `impl` blocks.
     (accepted, associated_consts, "1.20.0", Some(29646), None),
     /// Allows using associated `type`s in `trait`s.
@@ -172,7 +174,7 @@ declare_features! (
     // FIXME: explain `globs`.
     (accepted, globs, "1.0.0", None, None),
     /// Allows using `..=X` as a pattern.
-    (accepted, half_open_range_patterns, "CURRENT_RUSTC_VERSION", Some(67264), None),
+    (accepted, half_open_range_patterns, "1.66.0", Some(67264), None),
     /// Allows using the `u128` and `i128` types.
     (accepted, i128_type, "1.26.0", Some(35118), None),
     /// Allows the use of `if let` expressions.
@@ -189,6 +191,8 @@ declare_features! (
     (accepted, infer_outlives_requirements, "1.30.0", Some(44493), None),
     /// Allows irrefutable patterns in `if let` and `while let` statements (RFC 2086).
     (accepted, irrefutable_let_patterns, "1.33.0", Some(44495), None),
+    /// Allows `#[instruction_set(_)]` attribute.
+    (accepted, isa_attribute, "CURRENT_RUSTC_VERSION", Some(74727), None),
     /// Allows some increased flexibility in the name resolution rules,
     /// especially around globs and shadowing (RFC 1560).
     (accepted, item_like_imports, "1.15.0", Some(35120), None),
diff --git a/compiler/rustc_feature/src/active.rs b/compiler/rustc_feature/src/active.rs
index 1b8d683b1336..5cf2fdde3925 100644
--- a/compiler/rustc_feature/src/active.rs
+++ b/compiler/rustc_feature/src/active.rs
@@ -152,6 +152,8 @@ declare_features! (
     (active, anonymous_lifetime_in_impl_trait, "1.63.0", None, None),
     /// Allows identifying the `compiler_builtins` crate.
     (active, compiler_builtins, "1.13.0", None, None),
+    /// Allows writing custom MIR
+    (active, custom_mir, "1.65.0", None, None),
     /// Outputs useful `assert!` messages
     (active, generic_assert, "1.63.0", None, None),
     /// Allows using the `rust-intrinsic`'s "ABI".
@@ -292,8 +294,6 @@ declare_features! (
     (incomplete, adt_const_params, "1.56.0", Some(95174), None),
     /// Allows defining an `#[alloc_error_handler]`.
     (active, alloc_error_handler, "1.29.0", Some(51540), None),
-    /// Allows explicit discriminants on non-unit enum variants.
-    (active, arbitrary_enum_discriminant, "1.37.0", Some(60553), None),
     /// Allows trait methods with arbitrary self types.
     (active, arbitrary_self_types, "1.23.0", Some(44874), None),
     /// Allows using `const` operands in inline assembly.
@@ -311,7 +311,7 @@ declare_features! (
     /// Allows `async || body` closures.
     (active, async_closure, "1.37.0", Some(62290), None),
     /// Alows async functions to be declared, implemented, and used in traits.
-    (incomplete, async_fn_in_trait, "CURRENT_RUSTC_VERSION", Some(91611), None),
+    (incomplete, async_fn_in_trait, "1.66.0", Some(91611), None),
     /// Allows `extern "C-unwind" fn` to enable unwinding across ABI boundaries.
     (active, c_unwind, "1.52.0", Some(74990), None),
     /// Allows using C-variadics.
@@ -390,6 +390,9 @@ declare_features! (
     (active, exclusive_range_pattern, "1.11.0", Some(37854), None),
     /// Allows exhaustive pattern matching on types that contain uninhabited types.
     (active, exhaustive_patterns, "1.13.0", Some(51085), None),
+    /// Allows using `efiapi`, `sysv64` and `win64` as calling convention
+    /// for functions with varargs.
+    (active, extended_varargs_abi_support, "1.65.0", Some(100189), None),
     /// Allows defining `extern type`s.
     (active, extern_types, "1.23.0", Some(43467), None),
     /// Allows the use of `#[ffi_const]` on foreign functions.
@@ -411,9 +414,11 @@ declare_features! (
     /// Allows non-trivial generic constants which have to have wfness manually propagated to callers
     (incomplete, generic_const_exprs, "1.56.0", Some(76560), None),
     /// Allows using `..=X` as a patterns in slices.
-    (active, half_open_range_patterns_in_slices, "CURRENT_RUSTC_VERSION", Some(67264), None),
+    (active, half_open_range_patterns_in_slices, "1.66.0", Some(67264), None),
     /// Allows `if let` guard in match arms.
     (active, if_let_guard, "1.47.0", Some(51114), None),
+    /// Allows `impl Trait` as output type in `Fn` traits in return position of functions.
+    (active, impl_trait_in_fn_trait_return, "1.64.0", Some(99697), None),
     /// Allows using imported `main` function
     (active, imported_main, "1.53.0", Some(28937), None),
     /// Allows associated types in inherent impls.
@@ -424,8 +429,6 @@ declare_features! (
     (incomplete, inline_const_pat, "1.58.0", Some(76001), None),
     /// Allows using `pointer` and `reference` in intra-doc links
     (active, intra_doc_pointers, "1.51.0", Some(80896), None),
-    /// Allows `#[instruction_set(_)]` attribute
-    (active, isa_attribute, "1.48.0", Some(74727), None),
     // Allows setting the threshold for the `large_assignments` lint.
     (active, large_assignments, "1.52.0", Some(83518), None),
     /// Allows `if/while p && let q = r && ...` chains.
@@ -509,9 +512,9 @@ declare_features! (
     (active, thread_local, "1.0.0", Some(29594), None),
     /// Allows defining `trait X = A + B;` alias items.
     (active, trait_alias, "1.24.0", Some(41517), None),
-    /// Allows upcasting trait objects via supertraits.
-    /// Trait upcasting is casting, e.g., `dyn Foo -> dyn Bar` where `Foo: Bar`.
-    (incomplete, trait_upcasting, "1.56.0", Some(65991), None),
+    /// Allows dyn upcasting trait objects via supertraits.
+    /// Dyn upcasting is casting, e.g., `dyn Foo -> dyn Bar` where `Foo: Bar`.
+    (active, trait_upcasting, "1.56.0", Some(65991), None),
     /// Allows #[repr(transparent)] on unions (RFC 2645).
     (active, transparent_unions, "1.37.0", Some(60405), None),
     /// Allows inconsistent bounds in where clauses.
diff --git a/compiler/rustc_feature/src/builtin_attrs.rs b/compiler/rustc_feature/src/builtin_attrs.rs
index 2ead3c2c8d48..4b6e068db431 100644
--- a/compiler/rustc_feature/src/builtin_attrs.rs
+++ b/compiler/rustc_feature/src/builtin_attrs.rs
@@ -147,7 +147,7 @@ pub enum AttributeDuplicates {
     FutureWarnPreceding,
 }
 
-/// A conveniece macro to deal with `$($expr)?`.
+/// A convenience macro to deal with `$($expr)?`.
 macro_rules! or_default {
     ($default:expr,) => {
         $default
@@ -391,6 +391,7 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
         DuplicatesOk, @only_local: true,
     ),
     ungated!(track_caller, Normal, template!(Word), WarnFollowing),
+    ungated!(instruction_set, Normal, template!(List: "set"), ErrorPreceding),
     gated!(
         no_sanitize, Normal,
         template!(List: "address, memory, thread"), DuplicatesOk,
@@ -452,11 +453,6 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
         optimize, Normal, template!(List: "size|speed"), ErrorPreceding, optimize_attribute,
         experimental!(optimize),
     ),
-    // RFC 2867
-    gated!(
-        instruction_set, Normal, template!(List: "set"), ErrorPreceding,
-        isa_attribute, experimental!(instruction_set)
-    ),
 
     gated!(
         ffi_returns_twice, Normal, template!(Word), WarnFollowing, experimental!(ffi_returns_twice)
@@ -554,10 +550,6 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
     rustc_attr!(rustc_reallocator, Normal, template!(Word), WarnFollowing, IMPL_DETAIL),
     rustc_attr!(rustc_deallocator, Normal, template!(Word), WarnFollowing, IMPL_DETAIL),
     rustc_attr!(rustc_allocator_zeroed, Normal, template!(Word), WarnFollowing, IMPL_DETAIL),
-    gated!(
-        alloc_error_handler, Normal, template!(Word), WarnFollowing,
-        experimental!(alloc_error_handler)
-    ),
     gated!(
         default_lib_allocator, Normal, template!(Word), WarnFollowing, allocator_internals,
         experimental!(default_lib_allocator),
@@ -699,6 +691,10 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
         rustc_allow_incoherent_impl, AttributeType::Normal, template!(Word), ErrorFollowing, @only_local: true,
         "#[rustc_allow_incoherent_impl] has to be added to all impl items of an incoherent inherent impl."
     ),
+    rustc_attr!(
+        rustc_deny_explicit_impl, AttributeType::Normal, template!(Word), ErrorFollowing, @only_local: false,
+        "#[rustc_deny_explicit_impl] enforces that a trait can have no user-provided impls"
+    ),
     rustc_attr!(
         rustc_has_incoherent_inherent_impls, AttributeType::Normal, template!(Word), ErrorFollowing,
         "#[rustc_has_incoherent_inherent_impls] allows the addition of incoherent inherent impls for \
@@ -818,6 +814,10 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
     rustc_attr!(TEST, rustc_polymorphize_error, Normal, template!(Word), WarnFollowing),
     rustc_attr!(TEST, rustc_def_path, Normal, template!(Word), WarnFollowing),
     rustc_attr!(TEST, rustc_mir, Normal, template!(List: "arg1, arg2, ..."), DuplicatesOk),
+    gated!(
+        custom_mir, Normal, template!(List: r#"dialect = "...", phase = "...""#),
+        ErrorFollowing, "the `#[custom_mir]` attribute is just used for the Rust test suite",
+    ),
     rustc_attr!(TEST, rustc_dump_program_clauses, Normal, template!(Word), WarnFollowing),
     rustc_attr!(TEST, rustc_dump_env_program_clauses, Normal, template!(Word), WarnFollowing),
     rustc_attr!(TEST, rustc_object_lifetime_default, Normal, template!(Word), WarnFollowing),
diff --git a/compiler/rustc_graphviz/src/lib.rs b/compiler/rustc_graphviz/src/lib.rs
index 3c1bb5532661..401d3f6689c9 100644
--- a/compiler/rustc_graphviz/src/lib.rs
+++ b/compiler/rustc_graphviz/src/lib.rs
@@ -471,7 +471,11 @@ pub trait Labeller<'a> {
 /// Escape tags in such a way that it is suitable for inclusion in a
 /// Graphviz HTML label.
 pub fn escape_html(s: &str) -> String {
-    s.replace('&', "&amp;").replace('\"', "&quot;").replace('<', "&lt;").replace('>', "&gt;")
+    s.replace('&', "&amp;")
+        .replace('\"', "&quot;")
+        .replace('<', "&lt;")
+        .replace('>', "&gt;")
+        .replace('\n', "<br align=\"left\"/>")
 }
 
 impl<'a> LabelText<'a> {
diff --git a/compiler/rustc_hir/src/hir.rs b/compiler/rustc_hir/src/hir.rs
index bc149e48d89e..82e260d158bc 100644
--- a/compiler/rustc_hir/src/hir.rs
+++ b/compiler/rustc_hir/src/hir.rs
@@ -388,6 +388,8 @@ impl<'hir> GenericArgs<'hir> {
     }
 
     #[inline]
+    /// This function returns the number of type and const generic params.
+    /// It should only be used for diagnostics.
     pub fn num_generic_params(&self) -> usize {
         self.args.iter().filter(|arg| !matches!(arg, GenericArg::Lifetime(_))).count()
     }
@@ -2207,14 +2209,14 @@ pub struct FnSig<'hir> {
 // so it can fetched later.
 #[derive(Copy, Clone, PartialEq, Eq, Encodable, Decodable, Debug, HashStable_Generic)]
 pub struct TraitItemId {
-    pub def_id: OwnerId,
+    pub owner_id: OwnerId,
 }
 
 impl TraitItemId {
     #[inline]
     pub fn hir_id(&self) -> HirId {
         // Items are always HIR owners.
-        HirId::make_owner(self.def_id.def_id)
+        HirId::make_owner(self.owner_id.def_id)
     }
 }
 
@@ -2225,7 +2227,7 @@ impl TraitItemId {
 #[derive(Debug, HashStable_Generic)]
 pub struct TraitItem<'hir> {
     pub ident: Ident,
-    pub def_id: OwnerId,
+    pub owner_id: OwnerId,
     pub generics: &'hir Generics<'hir>,
     pub kind: TraitItemKind<'hir>,
     pub span: Span,
@@ -2236,11 +2238,11 @@ impl TraitItem<'_> {
     #[inline]
     pub fn hir_id(&self) -> HirId {
         // Items are always HIR owners.
-        HirId::make_owner(self.def_id.def_id)
+        HirId::make_owner(self.owner_id.def_id)
     }
 
     pub fn trait_item_id(&self) -> TraitItemId {
-        TraitItemId { def_id: self.def_id }
+        TraitItemId { owner_id: self.owner_id }
     }
 }
 
@@ -2271,14 +2273,14 @@ pub enum TraitItemKind<'hir> {
 // so it can fetched later.
 #[derive(Copy, Clone, PartialEq, Eq, Encodable, Decodable, Debug, HashStable_Generic)]
 pub struct ImplItemId {
-    pub def_id: OwnerId,
+    pub owner_id: OwnerId,
 }
 
 impl ImplItemId {
     #[inline]
     pub fn hir_id(&self) -> HirId {
         // Items are always HIR owners.
-        HirId::make_owner(self.def_id.def_id)
+        HirId::make_owner(self.owner_id.def_id)
     }
 }
 
@@ -2286,7 +2288,7 @@ impl ImplItemId {
 #[derive(Debug, HashStable_Generic)]
 pub struct ImplItem<'hir> {
     pub ident: Ident,
-    pub def_id: OwnerId,
+    pub owner_id: OwnerId,
     pub generics: &'hir Generics<'hir>,
     pub kind: ImplItemKind<'hir>,
     pub defaultness: Defaultness,
@@ -2298,11 +2300,11 @@ impl ImplItem<'_> {
     #[inline]
     pub fn hir_id(&self) -> HirId {
         // Items are always HIR owners.
-        HirId::make_owner(self.def_id.def_id)
+        HirId::make_owner(self.owner_id.def_id)
     }
 
     pub fn impl_item_id(&self) -> ImplItemId {
-        ImplItemId { def_id: self.def_id }
+        ImplItemId { owner_id: self.owner_id }
     }
 }
 
@@ -2418,6 +2420,30 @@ impl<'hir> Ty<'hir> {
         }
         final_ty
     }
+
+    pub fn find_self_aliases(&self) -> Vec<Span> {
+        use crate::intravisit::Visitor;
+        struct MyVisitor(Vec<Span>);
+        impl<'v> Visitor<'v> for MyVisitor {
+            fn visit_ty(&mut self, t: &'v Ty<'v>) {
+                if matches!(
+                    &t.kind,
+                    TyKind::Path(QPath::Resolved(
+                        _,
+                        Path { res: crate::def::Res::SelfTyAlias { .. }, .. },
+                    ))
+                ) {
+                    self.0.push(t.span);
+                    return;
+                }
+                crate::intravisit::walk_ty(self, t);
+            }
+        }
+
+        let mut my_visitor = MyVisitor(vec![]);
+        my_visitor.visit_ty(self);
+        my_visitor.0
+    }
 }
 
 /// Not represented directly in the AST; referred to by name through a `ty_path`.
@@ -2890,14 +2916,14 @@ impl<'hir> VariantData<'hir> {
 // so it can fetched later.
 #[derive(Copy, Clone, PartialEq, Eq, Encodable, Decodable, Debug, Hash, HashStable_Generic)]
 pub struct ItemId {
-    pub def_id: OwnerId,
+    pub owner_id: OwnerId,
 }
 
 impl ItemId {
     #[inline]
     pub fn hir_id(&self) -> HirId {
         // Items are always HIR owners.
-        HirId::make_owner(self.def_id.def_id)
+        HirId::make_owner(self.owner_id.def_id)
     }
 }
 
@@ -2907,7 +2933,7 @@ impl ItemId {
 #[derive(Debug, HashStable_Generic)]
 pub struct Item<'hir> {
     pub ident: Ident,
-    pub def_id: OwnerId,
+    pub owner_id: OwnerId,
     pub kind: ItemKind<'hir>,
     pub span: Span,
     pub vis_span: Span,
@@ -2917,11 +2943,11 @@ impl Item<'_> {
     #[inline]
     pub fn hir_id(&self) -> HirId {
         // Items are always HIR owners.
-        HirId::make_owner(self.def_id.def_id)
+        HirId::make_owner(self.owner_id.def_id)
     }
 
     pub fn item_id(&self) -> ItemId {
-        ItemId { def_id: self.def_id }
+        ItemId { owner_id: self.owner_id }
     }
 }
 
@@ -3134,14 +3160,14 @@ pub enum AssocItemKind {
 // so it can fetched later.
 #[derive(Copy, Clone, PartialEq, Eq, Encodable, Decodable, Debug, HashStable_Generic)]
 pub struct ForeignItemId {
-    pub def_id: OwnerId,
+    pub owner_id: OwnerId,
 }
 
 impl ForeignItemId {
     #[inline]
     pub fn hir_id(&self) -> HirId {
         // Items are always HIR owners.
-        HirId::make_owner(self.def_id.def_id)
+        HirId::make_owner(self.owner_id.def_id)
     }
 }
 
@@ -3162,7 +3188,7 @@ pub struct ForeignItemRef {
 pub struct ForeignItem<'hir> {
     pub ident: Ident,
     pub kind: ForeignItemKind<'hir>,
-    pub def_id: OwnerId,
+    pub owner_id: OwnerId,
     pub span: Span,
     pub vis_span: Span,
 }
@@ -3171,11 +3197,11 @@ impl ForeignItem<'_> {
     #[inline]
     pub fn hir_id(&self) -> HirId {
         // Items are always HIR owners.
-        HirId::make_owner(self.def_id.def_id)
+        HirId::make_owner(self.owner_id.def_id)
     }
 
     pub fn foreign_item_id(&self) -> ForeignItemId {
-        ForeignItemId { def_id: self.def_id }
+        ForeignItemId { owner_id: self.owner_id }
     }
 }
 
@@ -3267,10 +3293,10 @@ impl<'hir> OwnerNode<'hir> {
 
     pub fn def_id(self) -> OwnerId {
         match self {
-            OwnerNode::Item(Item { def_id, .. })
-            | OwnerNode::TraitItem(TraitItem { def_id, .. })
-            | OwnerNode::ImplItem(ImplItem { def_id, .. })
-            | OwnerNode::ForeignItem(ForeignItem { def_id, .. }) => *def_id,
+            OwnerNode::Item(Item { owner_id, .. })
+            | OwnerNode::TraitItem(TraitItem { owner_id, .. })
+            | OwnerNode::ImplItem(ImplItem { owner_id, .. })
+            | OwnerNode::ForeignItem(ForeignItem { owner_id, .. }) => *owner_id,
             OwnerNode::Crate(..) => crate::CRATE_HIR_ID.owner,
         }
     }
diff --git a/compiler/rustc_hir/src/intravisit.rs b/compiler/rustc_hir/src/intravisit.rs
index f3bde099b134..3ef58d7d7057 100644
--- a/compiler/rustc_hir/src/intravisit.rs
+++ b/compiler/rustc_hir/src/intravisit.rs
@@ -358,6 +358,9 @@ pub trait Visitor<'v>: Sized {
     fn visit_where_predicate(&mut self, predicate: &'v WherePredicate<'v>) {
         walk_where_predicate(self, predicate)
     }
+    fn visit_fn_ret_ty(&mut self, ret_ty: &'v FnRetTy<'v>) {
+        walk_fn_ret_ty(self, ret_ty)
+    }
     fn visit_fn_decl(&mut self, fd: &'v FnDecl<'v>) {
         walk_fn_decl(self, fd)
     }
@@ -410,12 +413,7 @@ pub trait Visitor<'v>: Sized {
         walk_inf(self, inf);
     }
     fn visit_generic_arg(&mut self, generic_arg: &'v GenericArg<'v>) {
-        match generic_arg {
-            GenericArg::Lifetime(lt) => self.visit_lifetime(lt),
-            GenericArg::Type(ty) => self.visit_ty(ty),
-            GenericArg::Const(ct) => self.visit_anon_const(&ct.value),
-            GenericArg::Infer(inf) => self.visit_infer(inf),
-        }
+        walk_generic_arg(self, generic_arg);
     }
     fn visit_lifetime(&mut self, lifetime: &'v Lifetime) {
         walk_lifetime(self, lifetime)
@@ -448,63 +446,6 @@ pub trait Visitor<'v>: Sized {
     }
 }
 
-pub fn walk_mod<'v, V: Visitor<'v>>(visitor: &mut V, module: &'v Mod<'v>, mod_hir_id: HirId) {
-    visitor.visit_id(mod_hir_id);
-    for &item_id in module.item_ids {
-        visitor.visit_nested_item(item_id);
-    }
-}
-
-pub fn walk_body<'v, V: Visitor<'v>>(visitor: &mut V, body: &'v Body<'v>) {
-    walk_list!(visitor, visit_param, body.params);
-    visitor.visit_expr(&body.value);
-}
-
-pub fn walk_local<'v, V: Visitor<'v>>(visitor: &mut V, local: &'v Local<'v>) {
-    // Intentionally visiting the expr first - the initialization expr
-    // dominates the local's definition.
-    walk_list!(visitor, visit_expr, &local.init);
-    visitor.visit_id(local.hir_id);
-    visitor.visit_pat(&local.pat);
-    if let Some(els) = local.els {
-        visitor.visit_block(els);
-    }
-    walk_list!(visitor, visit_ty, &local.ty);
-}
-
-pub fn walk_ident<'v, V: Visitor<'v>>(visitor: &mut V, ident: Ident) {
-    visitor.visit_name(ident.name);
-}
-
-pub fn walk_label<'v, V: Visitor<'v>>(visitor: &mut V, label: &'v Label) {
-    visitor.visit_ident(label.ident);
-}
-
-pub fn walk_lifetime<'v, V: Visitor<'v>>(visitor: &mut V, lifetime: &'v Lifetime) {
-    visitor.visit_id(lifetime.hir_id);
-    match lifetime.name {
-        LifetimeName::Param(_, ParamName::Plain(ident)) => {
-            visitor.visit_ident(ident);
-        }
-        LifetimeName::Param(_, ParamName::Fresh)
-        | LifetimeName::Param(_, ParamName::Error)
-        | LifetimeName::Static
-        | LifetimeName::Error
-        | LifetimeName::ImplicitObjectLifetimeDefault
-        | LifetimeName::Infer => {}
-    }
-}
-
-pub fn walk_poly_trait_ref<'v, V: Visitor<'v>>(visitor: &mut V, trait_ref: &'v PolyTraitRef<'v>) {
-    walk_list!(visitor, visit_generic_param, trait_ref.bound_generic_params);
-    visitor.visit_trait_ref(&trait_ref.trait_ref);
-}
-
-pub fn walk_trait_ref<'v, V: Visitor<'v>>(visitor: &mut V, trait_ref: &'v TraitRef<'v>) {
-    visitor.visit_id(trait_ref.hir_ref_id);
-    visitor.visit_path(&trait_ref.path, trait_ref.hir_ref_id)
-}
-
 pub fn walk_param<'v, V: Visitor<'v>>(visitor: &mut V, param: &'v Param<'v>) {
     visitor.visit_id(param.hir_id);
     visitor.visit_pat(&param.pat);
@@ -601,142 +542,80 @@ pub fn walk_item<'v, V: Visitor<'v>>(visitor: &mut V, item: &'v Item<'v>) {
     }
 }
 
-pub fn walk_inline_asm<'v, V: Visitor<'v>>(visitor: &mut V, asm: &'v InlineAsm<'v>, id: HirId) {
-    for (op, op_sp) in asm.operands {
-        match op {
-            InlineAsmOperand::In { expr, .. } | InlineAsmOperand::InOut { expr, .. } => {
-                visitor.visit_expr(expr)
+pub fn walk_body<'v, V: Visitor<'v>>(visitor: &mut V, body: &'v Body<'v>) {
+    walk_list!(visitor, visit_param, body.params);
+    visitor.visit_expr(&body.value);
+}
+
+pub fn walk_ident<'v, V: Visitor<'v>>(visitor: &mut V, ident: Ident) {
+    visitor.visit_name(ident.name);
+}
+
+pub fn walk_mod<'v, V: Visitor<'v>>(visitor: &mut V, module: &'v Mod<'v>, mod_hir_id: HirId) {
+    visitor.visit_id(mod_hir_id);
+    for &item_id in module.item_ids {
+        visitor.visit_nested_item(item_id);
+    }
+}
+
+pub fn walk_foreign_item<'v, V: Visitor<'v>>(visitor: &mut V, foreign_item: &'v ForeignItem<'v>) {
+    visitor.visit_id(foreign_item.hir_id());
+    visitor.visit_ident(foreign_item.ident);
+
+    match foreign_item.kind {
+        ForeignItemKind::Fn(ref function_declaration, param_names, ref generics) => {
+            visitor.visit_generics(generics);
+            visitor.visit_fn_decl(function_declaration);
+            for &param_name in param_names {
+                visitor.visit_ident(param_name);
             }
-            InlineAsmOperand::Out { expr, .. } => {
-                if let Some(expr) = expr {
-                    visitor.visit_expr(expr);
-                }
+        }
+        ForeignItemKind::Static(ref typ, _) => visitor.visit_ty(typ),
+        ForeignItemKind::Type => (),
+    }
+}
+
+pub fn walk_local<'v, V: Visitor<'v>>(visitor: &mut V, local: &'v Local<'v>) {
+    // Intentionally visiting the expr first - the initialization expr
+    // dominates the local's definition.
+    walk_list!(visitor, visit_expr, &local.init);
+    visitor.visit_id(local.hir_id);
+    visitor.visit_pat(&local.pat);
+    if let Some(els) = local.els {
+        visitor.visit_block(els);
+    }
+    walk_list!(visitor, visit_ty, &local.ty);
+}
+
+pub fn walk_block<'v, V: Visitor<'v>>(visitor: &mut V, block: &'v Block<'v>) {
+    visitor.visit_id(block.hir_id);
+    walk_list!(visitor, visit_stmt, block.stmts);
+    walk_list!(visitor, visit_expr, &block.expr);
+}
+
+pub fn walk_stmt<'v, V: Visitor<'v>>(visitor: &mut V, statement: &'v Stmt<'v>) {
+    visitor.visit_id(statement.hir_id);
+    match statement.kind {
+        StmtKind::Local(ref local) => visitor.visit_local(local),
+        StmtKind::Item(item) => visitor.visit_nested_item(item),
+        StmtKind::Expr(ref expression) | StmtKind::Semi(ref expression) => {
+            visitor.visit_expr(expression)
+        }
+    }
+}
+
+pub fn walk_arm<'v, V: Visitor<'v>>(visitor: &mut V, arm: &'v Arm<'v>) {
+    visitor.visit_id(arm.hir_id);
+    visitor.visit_pat(&arm.pat);
+    if let Some(ref g) = arm.guard {
+        match g {
+            Guard::If(ref e) => visitor.visit_expr(e),
+            Guard::IfLet(ref l) => {
+                visitor.visit_let_expr(l);
             }
-            InlineAsmOperand::SplitInOut { in_expr, out_expr, .. } => {
-                visitor.visit_expr(in_expr);
-                if let Some(out_expr) = out_expr {
-                    visitor.visit_expr(out_expr);
-                }
-            }
-            InlineAsmOperand::Const { anon_const, .. }
-            | InlineAsmOperand::SymFn { anon_const, .. } => visitor.visit_anon_const(anon_const),
-            InlineAsmOperand::SymStatic { path, .. } => visitor.visit_qpath(path, id, *op_sp),
         }
     }
-}
-
-pub fn walk_use<'v, V: Visitor<'v>>(visitor: &mut V, path: &'v Path<'v>, hir_id: HirId) {
-    visitor.visit_id(hir_id);
-    visitor.visit_path(path, hir_id);
-}
-
-pub fn walk_enum_def<'v, V: Visitor<'v>>(
-    visitor: &mut V,
-    enum_definition: &'v EnumDef<'v>,
-    item_id: HirId,
-) {
-    visitor.visit_id(item_id);
-    walk_list!(visitor, visit_variant, enum_definition.variants);
-}
-
-pub fn walk_variant<'v, V: Visitor<'v>>(visitor: &mut V, variant: &'v Variant<'v>) {
-    visitor.visit_ident(variant.ident);
-    visitor.visit_id(variant.id);
-    visitor.visit_variant_data(&variant.data);
-    walk_list!(visitor, visit_anon_const, &variant.disr_expr);
-}
-
-pub fn walk_ty<'v, V: Visitor<'v>>(visitor: &mut V, typ: &'v Ty<'v>) {
-    visitor.visit_id(typ.hir_id);
-
-    match typ.kind {
-        TyKind::Slice(ref ty) => visitor.visit_ty(ty),
-        TyKind::Ptr(ref mutable_type) => visitor.visit_ty(&mutable_type.ty),
-        TyKind::Rptr(ref lifetime, ref mutable_type) => {
-            visitor.visit_lifetime(lifetime);
-            visitor.visit_ty(&mutable_type.ty)
-        }
-        TyKind::Never => {}
-        TyKind::Tup(tuple_element_types) => {
-            walk_list!(visitor, visit_ty, tuple_element_types);
-        }
-        TyKind::BareFn(ref function_declaration) => {
-            walk_list!(visitor, visit_generic_param, function_declaration.generic_params);
-            visitor.visit_fn_decl(&function_declaration.decl);
-        }
-        TyKind::Path(ref qpath) => {
-            visitor.visit_qpath(qpath, typ.hir_id, typ.span);
-        }
-        TyKind::OpaqueDef(item_id, lifetimes, _in_trait) => {
-            visitor.visit_nested_item(item_id);
-            walk_list!(visitor, visit_generic_arg, lifetimes);
-        }
-        TyKind::Array(ref ty, ref length) => {
-            visitor.visit_ty(ty);
-            visitor.visit_array_length(length)
-        }
-        TyKind::TraitObject(bounds, ref lifetime, _syntax) => {
-            for bound in bounds {
-                visitor.visit_poly_trait_ref(bound);
-            }
-            visitor.visit_lifetime(lifetime);
-        }
-        TyKind::Typeof(ref expression) => visitor.visit_anon_const(expression),
-        TyKind::Infer | TyKind::Err => {}
-    }
-}
-
-pub fn walk_inf<'v, V: Visitor<'v>>(visitor: &mut V, inf: &'v InferArg) {
-    visitor.visit_id(inf.hir_id);
-}
-
-pub fn walk_qpath<'v, V: Visitor<'v>>(visitor: &mut V, qpath: &'v QPath<'v>, id: HirId) {
-    match *qpath {
-        QPath::Resolved(ref maybe_qself, ref path) => {
-            walk_list!(visitor, visit_ty, maybe_qself);
-            visitor.visit_path(path, id)
-        }
-        QPath::TypeRelative(ref qself, ref segment) => {
-            visitor.visit_ty(qself);
-            visitor.visit_path_segment(segment);
-        }
-        QPath::LangItem(..) => {}
-    }
-}
-
-pub fn walk_path<'v, V: Visitor<'v>>(visitor: &mut V, path: &'v Path<'v>) {
-    for segment in path.segments {
-        visitor.visit_path_segment(segment);
-    }
-}
-
-pub fn walk_path_segment<'v, V: Visitor<'v>>(visitor: &mut V, segment: &'v PathSegment<'v>) {
-    visitor.visit_ident(segment.ident);
-    visitor.visit_id(segment.hir_id);
-    if let Some(ref args) = segment.args {
-        visitor.visit_generic_args(args);
-    }
-}
-
-pub fn walk_generic_args<'v, V: Visitor<'v>>(visitor: &mut V, generic_args: &'v GenericArgs<'v>) {
-    walk_list!(visitor, visit_generic_arg, generic_args.args);
-    walk_list!(visitor, visit_assoc_type_binding, generic_args.bindings);
-}
-
-pub fn walk_assoc_type_binding<'v, V: Visitor<'v>>(
-    visitor: &mut V,
-    type_binding: &'v TypeBinding<'v>,
-) {
-    visitor.visit_id(type_binding.hir_id);
-    visitor.visit_ident(type_binding.ident);
-    visitor.visit_generic_args(type_binding.gen_args);
-    match type_binding.kind {
-        TypeBindingKind::Equality { ref term } => match term {
-            Term::Ty(ref ty) => visitor.visit_ty(ty),
-            Term::Const(ref c) => visitor.visit_anon_const(c),
-        },
-        TypeBindingKind::Constraint { bounds } => walk_list!(visitor, visit_param_bound, bounds),
-    }
+    visitor.visit_expr(&arm.body);
 }
 
 pub fn walk_pat<'v, V: Visitor<'v>>(visitor: &mut V, pattern: &'v Pat<'v>) {
@@ -784,257 +663,6 @@ pub fn walk_pat_field<'v, V: Visitor<'v>>(visitor: &mut V, field: &'v PatField<'
     visitor.visit_pat(&field.pat)
 }
 
-pub fn walk_foreign_item<'v, V: Visitor<'v>>(visitor: &mut V, foreign_item: &'v ForeignItem<'v>) {
-    visitor.visit_id(foreign_item.hir_id());
-    visitor.visit_ident(foreign_item.ident);
-
-    match foreign_item.kind {
-        ForeignItemKind::Fn(ref function_declaration, param_names, ref generics) => {
-            visitor.visit_generics(generics);
-            visitor.visit_fn_decl(function_declaration);
-            for &param_name in param_names {
-                visitor.visit_ident(param_name);
-            }
-        }
-        ForeignItemKind::Static(ref typ, _) => visitor.visit_ty(typ),
-        ForeignItemKind::Type => (),
-    }
-}
-
-pub fn walk_param_bound<'v, V: Visitor<'v>>(visitor: &mut V, bound: &'v GenericBound<'v>) {
-    match *bound {
-        GenericBound::Trait(ref typ, _modifier) => {
-            visitor.visit_poly_trait_ref(typ);
-        }
-        GenericBound::LangItemTrait(_, _span, hir_id, args) => {
-            visitor.visit_id(hir_id);
-            visitor.visit_generic_args(args);
-        }
-        GenericBound::Outlives(ref lifetime) => visitor.visit_lifetime(lifetime),
-    }
-}
-
-pub fn walk_generic_param<'v, V: Visitor<'v>>(visitor: &mut V, param: &'v GenericParam<'v>) {
-    visitor.visit_id(param.hir_id);
-    match param.name {
-        ParamName::Plain(ident) => visitor.visit_ident(ident),
-        ParamName::Error | ParamName::Fresh => {}
-    }
-    match param.kind {
-        GenericParamKind::Lifetime { .. } => {}
-        GenericParamKind::Type { ref default, .. } => walk_list!(visitor, visit_ty, default),
-        GenericParamKind::Const { ref ty, ref default } => {
-            visitor.visit_ty(ty);
-            if let Some(ref default) = default {
-                visitor.visit_const_param_default(param.hir_id, default);
-            }
-        }
-    }
-}
-
-pub fn walk_const_param_default<'v, V: Visitor<'v>>(visitor: &mut V, ct: &'v AnonConst) {
-    visitor.visit_anon_const(ct)
-}
-
-pub fn walk_generics<'v, V: Visitor<'v>>(visitor: &mut V, generics: &'v Generics<'v>) {
-    walk_list!(visitor, visit_generic_param, generics.params);
-    walk_list!(visitor, visit_where_predicate, generics.predicates);
-}
-
-pub fn walk_where_predicate<'v, V: Visitor<'v>>(
-    visitor: &mut V,
-    predicate: &'v WherePredicate<'v>,
-) {
-    match *predicate {
-        WherePredicate::BoundPredicate(WhereBoundPredicate {
-            hir_id,
-            ref bounded_ty,
-            bounds,
-            bound_generic_params,
-            origin: _,
-            span: _,
-        }) => {
-            visitor.visit_id(hir_id);
-            visitor.visit_ty(bounded_ty);
-            walk_list!(visitor, visit_param_bound, bounds);
-            walk_list!(visitor, visit_generic_param, bound_generic_params);
-        }
-        WherePredicate::RegionPredicate(WhereRegionPredicate {
-            ref lifetime,
-            bounds,
-            span: _,
-            in_where_clause: _,
-        }) => {
-            visitor.visit_lifetime(lifetime);
-            walk_list!(visitor, visit_param_bound, bounds);
-        }
-        WherePredicate::EqPredicate(WhereEqPredicate { ref lhs_ty, ref rhs_ty, span: _ }) => {
-            visitor.visit_ty(lhs_ty);
-            visitor.visit_ty(rhs_ty);
-        }
-    }
-}
-
-pub fn walk_fn_ret_ty<'v, V: Visitor<'v>>(visitor: &mut V, ret_ty: &'v FnRetTy<'v>) {
-    if let FnRetTy::Return(ref output_ty) = *ret_ty {
-        visitor.visit_ty(output_ty)
-    }
-}
-
-pub fn walk_fn_decl<'v, V: Visitor<'v>>(visitor: &mut V, function_declaration: &'v FnDecl<'v>) {
-    for ty in function_declaration.inputs {
-        visitor.visit_ty(ty)
-    }
-    walk_fn_ret_ty(visitor, &function_declaration.output)
-}
-
-pub fn walk_fn_kind<'v, V: Visitor<'v>>(visitor: &mut V, function_kind: FnKind<'v>) {
-    match function_kind {
-        FnKind::ItemFn(_, generics, ..) => {
-            visitor.visit_generics(generics);
-        }
-        FnKind::Closure | FnKind::Method(..) => {}
-    }
-}
-
-pub fn walk_fn<'v, V: Visitor<'v>>(
-    visitor: &mut V,
-    function_kind: FnKind<'v>,
-    function_declaration: &'v FnDecl<'v>,
-    body_id: BodyId,
-    id: HirId,
-) {
-    visitor.visit_id(id);
-    visitor.visit_fn_decl(function_declaration);
-    walk_fn_kind(visitor, function_kind);
-    visitor.visit_nested_body(body_id)
-}
-
-pub fn walk_trait_item<'v, V: Visitor<'v>>(visitor: &mut V, trait_item: &'v TraitItem<'v>) {
-    // N.B., deliberately force a compilation error if/when new fields are added.
-    let TraitItem { ident, generics, ref defaultness, ref kind, span, def_id: _ } = *trait_item;
-    let hir_id = trait_item.hir_id();
-    visitor.visit_ident(ident);
-    visitor.visit_generics(&generics);
-    visitor.visit_defaultness(&defaultness);
-    match *kind {
-        TraitItemKind::Const(ref ty, default) => {
-            visitor.visit_id(hir_id);
-            visitor.visit_ty(ty);
-            walk_list!(visitor, visit_nested_body, default);
-        }
-        TraitItemKind::Fn(ref sig, TraitFn::Required(param_names)) => {
-            visitor.visit_id(hir_id);
-            visitor.visit_fn_decl(&sig.decl);
-            for &param_name in param_names {
-                visitor.visit_ident(param_name);
-            }
-        }
-        TraitItemKind::Fn(ref sig, TraitFn::Provided(body_id)) => {
-            visitor.visit_fn(FnKind::Method(ident, sig), &sig.decl, body_id, span, hir_id);
-        }
-        TraitItemKind::Type(bounds, ref default) => {
-            visitor.visit_id(hir_id);
-            walk_list!(visitor, visit_param_bound, bounds);
-            walk_list!(visitor, visit_ty, default);
-        }
-    }
-}
-
-pub fn walk_trait_item_ref<'v, V: Visitor<'v>>(visitor: &mut V, trait_item_ref: &'v TraitItemRef) {
-    // N.B., deliberately force a compilation error if/when new fields are added.
-    let TraitItemRef { id, ident, ref kind, span: _ } = *trait_item_ref;
-    visitor.visit_nested_trait_item(id);
-    visitor.visit_ident(ident);
-    visitor.visit_associated_item_kind(kind);
-}
-
-pub fn walk_impl_item<'v, V: Visitor<'v>>(visitor: &mut V, impl_item: &'v ImplItem<'v>) {
-    // N.B., deliberately force a compilation error if/when new fields are added.
-    let ImplItem {
-        def_id: _,
-        ident,
-        ref generics,
-        ref kind,
-        ref defaultness,
-        span: _,
-        vis_span: _,
-    } = *impl_item;
-
-    visitor.visit_ident(ident);
-    visitor.visit_generics(generics);
-    visitor.visit_defaultness(defaultness);
-    match *kind {
-        ImplItemKind::Const(ref ty, body) => {
-            visitor.visit_id(impl_item.hir_id());
-            visitor.visit_ty(ty);
-            visitor.visit_nested_body(body);
-        }
-        ImplItemKind::Fn(ref sig, body_id) => {
-            visitor.visit_fn(
-                FnKind::Method(impl_item.ident, sig),
-                &sig.decl,
-                body_id,
-                impl_item.span,
-                impl_item.hir_id(),
-            );
-        }
-        ImplItemKind::Type(ref ty) => {
-            visitor.visit_id(impl_item.hir_id());
-            visitor.visit_ty(ty);
-        }
-    }
-}
-
-pub fn walk_foreign_item_ref<'v, V: Visitor<'v>>(
-    visitor: &mut V,
-    foreign_item_ref: &'v ForeignItemRef,
-) {
-    // N.B., deliberately force a compilation error if/when new fields are added.
-    let ForeignItemRef { id, ident, span: _ } = *foreign_item_ref;
-    visitor.visit_nested_foreign_item(id);
-    visitor.visit_ident(ident);
-}
-
-pub fn walk_impl_item_ref<'v, V: Visitor<'v>>(visitor: &mut V, impl_item_ref: &'v ImplItemRef) {
-    // N.B., deliberately force a compilation error if/when new fields are added.
-    let ImplItemRef { id, ident, ref kind, span: _, trait_item_def_id: _ } = *impl_item_ref;
-    visitor.visit_nested_impl_item(id);
-    visitor.visit_ident(ident);
-    visitor.visit_associated_item_kind(kind);
-}
-
-pub fn walk_struct_def<'v, V: Visitor<'v>>(
-    visitor: &mut V,
-    struct_definition: &'v VariantData<'v>,
-) {
-    walk_list!(visitor, visit_id, struct_definition.ctor_hir_id());
-    walk_list!(visitor, visit_field_def, struct_definition.fields());
-}
-
-pub fn walk_field_def<'v, V: Visitor<'v>>(visitor: &mut V, field: &'v FieldDef<'v>) {
-    visitor.visit_id(field.hir_id);
-    visitor.visit_ident(field.ident);
-    visitor.visit_ty(&field.ty);
-}
-
-pub fn walk_block<'v, V: Visitor<'v>>(visitor: &mut V, block: &'v Block<'v>) {
-    visitor.visit_id(block.hir_id);
-    walk_list!(visitor, visit_stmt, block.stmts);
-    walk_list!(visitor, visit_expr, &block.expr);
-}
-
-pub fn walk_stmt<'v, V: Visitor<'v>>(visitor: &mut V, statement: &'v Stmt<'v>) {
-    visitor.visit_id(statement.hir_id);
-    match statement.kind {
-        StmtKind::Local(ref local) => visitor.visit_local(local),
-        StmtKind::Item(item) => visitor.visit_nested_item(item),
-        StmtKind::Expr(ref expression) | StmtKind::Semi(ref expression) => {
-            visitor.visit_expr(expression)
-        }
-    }
-}
-
 pub fn walk_array_len<'v, V: Visitor<'v>>(visitor: &mut V, len: &'v ArrayLen) {
     match len {
         &ArrayLen::Infer(hir_id, _span) => visitor.visit_id(hir_id),
@@ -1047,20 +675,6 @@ pub fn walk_anon_const<'v, V: Visitor<'v>>(visitor: &mut V, constant: &'v AnonCo
     visitor.visit_nested_body(constant.body);
 }
 
-pub fn walk_let_expr<'v, V: Visitor<'v>>(visitor: &mut V, let_expr: &'v Let<'v>) {
-    // match the visit order in walk_local
-    visitor.visit_expr(let_expr.init);
-    visitor.visit_id(let_expr.hir_id);
-    visitor.visit_pat(let_expr.pat);
-    walk_list!(visitor, visit_ty, let_expr.ty);
-}
-
-pub fn walk_expr_field<'v, V: Visitor<'v>>(visitor: &mut V, field: &'v ExprField<'v>) {
-    visitor.visit_id(field.hir_id);
-    visitor.visit_ident(field.ident);
-    visitor.visit_expr(&field.expr)
-}
-
 pub fn walk_expr<'v, V: Visitor<'v>>(visitor: &mut V, expression: &'v Expr<'v>) {
     visitor.visit_id(expression.hir_id);
     match expression.kind {
@@ -1173,18 +787,387 @@ pub fn walk_expr<'v, V: Visitor<'v>>(visitor: &mut V, expression: &'v Expr<'v>)
     }
 }
 
-pub fn walk_arm<'v, V: Visitor<'v>>(visitor: &mut V, arm: &'v Arm<'v>) {
-    visitor.visit_id(arm.hir_id);
-    visitor.visit_pat(&arm.pat);
-    if let Some(ref g) = arm.guard {
-        match g {
-            Guard::If(ref e) => visitor.visit_expr(e),
-            Guard::IfLet(ref l) => {
-                visitor.visit_let_expr(l);
+pub fn walk_let_expr<'v, V: Visitor<'v>>(visitor: &mut V, let_expr: &'v Let<'v>) {
+    // match the visit order in walk_local
+    visitor.visit_expr(let_expr.init);
+    visitor.visit_id(let_expr.hir_id);
+    visitor.visit_pat(let_expr.pat);
+    walk_list!(visitor, visit_ty, let_expr.ty);
+}
+
+pub fn walk_expr_field<'v, V: Visitor<'v>>(visitor: &mut V, field: &'v ExprField<'v>) {
+    visitor.visit_id(field.hir_id);
+    visitor.visit_ident(field.ident);
+    visitor.visit_expr(&field.expr)
+}
+
+pub fn walk_ty<'v, V: Visitor<'v>>(visitor: &mut V, typ: &'v Ty<'v>) {
+    visitor.visit_id(typ.hir_id);
+
+    match typ.kind {
+        TyKind::Slice(ref ty) => visitor.visit_ty(ty),
+        TyKind::Ptr(ref mutable_type) => visitor.visit_ty(&mutable_type.ty),
+        TyKind::Rptr(ref lifetime, ref mutable_type) => {
+            visitor.visit_lifetime(lifetime);
+            visitor.visit_ty(&mutable_type.ty)
+        }
+        TyKind::Never => {}
+        TyKind::Tup(tuple_element_types) => {
+            walk_list!(visitor, visit_ty, tuple_element_types);
+        }
+        TyKind::BareFn(ref function_declaration) => {
+            walk_list!(visitor, visit_generic_param, function_declaration.generic_params);
+            visitor.visit_fn_decl(&function_declaration.decl);
+        }
+        TyKind::Path(ref qpath) => {
+            visitor.visit_qpath(qpath, typ.hir_id, typ.span);
+        }
+        TyKind::OpaqueDef(item_id, lifetimes, _in_trait) => {
+            visitor.visit_nested_item(item_id);
+            walk_list!(visitor, visit_generic_arg, lifetimes);
+        }
+        TyKind::Array(ref ty, ref length) => {
+            visitor.visit_ty(ty);
+            visitor.visit_array_length(length)
+        }
+        TyKind::TraitObject(bounds, ref lifetime, _syntax) => {
+            for bound in bounds {
+                visitor.visit_poly_trait_ref(bound);
+            }
+            visitor.visit_lifetime(lifetime);
+        }
+        TyKind::Typeof(ref expression) => visitor.visit_anon_const(expression),
+        TyKind::Infer | TyKind::Err => {}
+    }
+}
+
+pub fn walk_generic_param<'v, V: Visitor<'v>>(visitor: &mut V, param: &'v GenericParam<'v>) {
+    visitor.visit_id(param.hir_id);
+    match param.name {
+        ParamName::Plain(ident) => visitor.visit_ident(ident),
+        ParamName::Error | ParamName::Fresh => {}
+    }
+    match param.kind {
+        GenericParamKind::Lifetime { .. } => {}
+        GenericParamKind::Type { ref default, .. } => walk_list!(visitor, visit_ty, default),
+        GenericParamKind::Const { ref ty, ref default } => {
+            visitor.visit_ty(ty);
+            if let Some(ref default) = default {
+                visitor.visit_const_param_default(param.hir_id, default);
             }
         }
     }
-    visitor.visit_expr(&arm.body);
+}
+
+pub fn walk_const_param_default<'v, V: Visitor<'v>>(visitor: &mut V, ct: &'v AnonConst) {
+    visitor.visit_anon_const(ct)
+}
+
+pub fn walk_generics<'v, V: Visitor<'v>>(visitor: &mut V, generics: &'v Generics<'v>) {
+    walk_list!(visitor, visit_generic_param, generics.params);
+    walk_list!(visitor, visit_where_predicate, generics.predicates);
+}
+
+pub fn walk_where_predicate<'v, V: Visitor<'v>>(
+    visitor: &mut V,
+    predicate: &'v WherePredicate<'v>,
+) {
+    match *predicate {
+        WherePredicate::BoundPredicate(WhereBoundPredicate {
+            hir_id,
+            ref bounded_ty,
+            bounds,
+            bound_generic_params,
+            origin: _,
+            span: _,
+        }) => {
+            visitor.visit_id(hir_id);
+            visitor.visit_ty(bounded_ty);
+            walk_list!(visitor, visit_param_bound, bounds);
+            walk_list!(visitor, visit_generic_param, bound_generic_params);
+        }
+        WherePredicate::RegionPredicate(WhereRegionPredicate {
+            ref lifetime,
+            bounds,
+            span: _,
+            in_where_clause: _,
+        }) => {
+            visitor.visit_lifetime(lifetime);
+            walk_list!(visitor, visit_param_bound, bounds);
+        }
+        WherePredicate::EqPredicate(WhereEqPredicate { ref lhs_ty, ref rhs_ty, span: _ }) => {
+            visitor.visit_ty(lhs_ty);
+            visitor.visit_ty(rhs_ty);
+        }
+    }
+}
+
+pub fn walk_fn_decl<'v, V: Visitor<'v>>(visitor: &mut V, function_declaration: &'v FnDecl<'v>) {
+    for ty in function_declaration.inputs {
+        visitor.visit_ty(ty)
+    }
+    visitor.visit_fn_ret_ty(&function_declaration.output)
+}
+
+pub fn walk_fn_ret_ty<'v, V: Visitor<'v>>(visitor: &mut V, ret_ty: &'v FnRetTy<'v>) {
+    if let FnRetTy::Return(ref output_ty) = *ret_ty {
+        visitor.visit_ty(output_ty)
+    }
+}
+
+pub fn walk_fn<'v, V: Visitor<'v>>(
+    visitor: &mut V,
+    function_kind: FnKind<'v>,
+    function_declaration: &'v FnDecl<'v>,
+    body_id: BodyId,
+    id: HirId,
+) {
+    visitor.visit_id(id);
+    visitor.visit_fn_decl(function_declaration);
+    walk_fn_kind(visitor, function_kind);
+    visitor.visit_nested_body(body_id)
+}
+
+pub fn walk_fn_kind<'v, V: Visitor<'v>>(visitor: &mut V, function_kind: FnKind<'v>) {
+    match function_kind {
+        FnKind::ItemFn(_, generics, ..) => {
+            visitor.visit_generics(generics);
+        }
+        FnKind::Closure | FnKind::Method(..) => {}
+    }
+}
+
+pub fn walk_use<'v, V: Visitor<'v>>(visitor: &mut V, path: &'v Path<'v>, hir_id: HirId) {
+    visitor.visit_id(hir_id);
+    visitor.visit_path(path, hir_id);
+}
+
+pub fn walk_trait_item<'v, V: Visitor<'v>>(visitor: &mut V, trait_item: &'v TraitItem<'v>) {
+    // N.B., deliberately force a compilation error if/when new fields are added.
+    let TraitItem { ident, generics, ref defaultness, ref kind, span, owner_id: _ } = *trait_item;
+    let hir_id = trait_item.hir_id();
+    visitor.visit_ident(ident);
+    visitor.visit_generics(&generics);
+    visitor.visit_defaultness(&defaultness);
+    match *kind {
+        TraitItemKind::Const(ref ty, default) => {
+            visitor.visit_id(hir_id);
+            visitor.visit_ty(ty);
+            walk_list!(visitor, visit_nested_body, default);
+        }
+        TraitItemKind::Fn(ref sig, TraitFn::Required(param_names)) => {
+            visitor.visit_id(hir_id);
+            visitor.visit_fn_decl(&sig.decl);
+            for &param_name in param_names {
+                visitor.visit_ident(param_name);
+            }
+        }
+        TraitItemKind::Fn(ref sig, TraitFn::Provided(body_id)) => {
+            visitor.visit_fn(FnKind::Method(ident, sig), &sig.decl, body_id, span, hir_id);
+        }
+        TraitItemKind::Type(bounds, ref default) => {
+            visitor.visit_id(hir_id);
+            walk_list!(visitor, visit_param_bound, bounds);
+            walk_list!(visitor, visit_ty, default);
+        }
+    }
+}
+
+pub fn walk_trait_item_ref<'v, V: Visitor<'v>>(visitor: &mut V, trait_item_ref: &'v TraitItemRef) {
+    // N.B., deliberately force a compilation error if/when new fields are added.
+    let TraitItemRef { id, ident, ref kind, span: _ } = *trait_item_ref;
+    visitor.visit_nested_trait_item(id);
+    visitor.visit_ident(ident);
+    visitor.visit_associated_item_kind(kind);
+}
+
+pub fn walk_impl_item<'v, V: Visitor<'v>>(visitor: &mut V, impl_item: &'v ImplItem<'v>) {
+    // N.B., deliberately force a compilation error if/when new fields are added.
+    let ImplItem {
+        owner_id: _,
+        ident,
+        ref generics,
+        ref kind,
+        ref defaultness,
+        span: _,
+        vis_span: _,
+    } = *impl_item;
+
+    visitor.visit_ident(ident);
+    visitor.visit_generics(generics);
+    visitor.visit_defaultness(defaultness);
+    match *kind {
+        ImplItemKind::Const(ref ty, body) => {
+            visitor.visit_id(impl_item.hir_id());
+            visitor.visit_ty(ty);
+            visitor.visit_nested_body(body);
+        }
+        ImplItemKind::Fn(ref sig, body_id) => {
+            visitor.visit_fn(
+                FnKind::Method(impl_item.ident, sig),
+                &sig.decl,
+                body_id,
+                impl_item.span,
+                impl_item.hir_id(),
+            );
+        }
+        ImplItemKind::Type(ref ty) => {
+            visitor.visit_id(impl_item.hir_id());
+            visitor.visit_ty(ty);
+        }
+    }
+}
+
+pub fn walk_foreign_item_ref<'v, V: Visitor<'v>>(
+    visitor: &mut V,
+    foreign_item_ref: &'v ForeignItemRef,
+) {
+    // N.B., deliberately force a compilation error if/when new fields are added.
+    let ForeignItemRef { id, ident, span: _ } = *foreign_item_ref;
+    visitor.visit_nested_foreign_item(id);
+    visitor.visit_ident(ident);
+}
+
+pub fn walk_impl_item_ref<'v, V: Visitor<'v>>(visitor: &mut V, impl_item_ref: &'v ImplItemRef) {
+    // N.B., deliberately force a compilation error if/when new fields are added.
+    let ImplItemRef { id, ident, ref kind, span: _, trait_item_def_id: _ } = *impl_item_ref;
+    visitor.visit_nested_impl_item(id);
+    visitor.visit_ident(ident);
+    visitor.visit_associated_item_kind(kind);
+}
+
+pub fn walk_trait_ref<'v, V: Visitor<'v>>(visitor: &mut V, trait_ref: &'v TraitRef<'v>) {
+    visitor.visit_id(trait_ref.hir_ref_id);
+    visitor.visit_path(&trait_ref.path, trait_ref.hir_ref_id)
+}
+
+pub fn walk_param_bound<'v, V: Visitor<'v>>(visitor: &mut V, bound: &'v GenericBound<'v>) {
+    match *bound {
+        GenericBound::Trait(ref typ, _modifier) => {
+            visitor.visit_poly_trait_ref(typ);
+        }
+        GenericBound::LangItemTrait(_, _span, hir_id, args) => {
+            visitor.visit_id(hir_id);
+            visitor.visit_generic_args(args);
+        }
+        GenericBound::Outlives(ref lifetime) => visitor.visit_lifetime(lifetime),
+    }
+}
+
+pub fn walk_poly_trait_ref<'v, V: Visitor<'v>>(visitor: &mut V, trait_ref: &'v PolyTraitRef<'v>) {
+    walk_list!(visitor, visit_generic_param, trait_ref.bound_generic_params);
+    visitor.visit_trait_ref(&trait_ref.trait_ref);
+}
+
+pub fn walk_struct_def<'v, V: Visitor<'v>>(
+    visitor: &mut V,
+    struct_definition: &'v VariantData<'v>,
+) {
+    walk_list!(visitor, visit_id, struct_definition.ctor_hir_id());
+    walk_list!(visitor, visit_field_def, struct_definition.fields());
+}
+
+pub fn walk_field_def<'v, V: Visitor<'v>>(visitor: &mut V, field: &'v FieldDef<'v>) {
+    visitor.visit_id(field.hir_id);
+    visitor.visit_ident(field.ident);
+    visitor.visit_ty(&field.ty);
+}
+
+pub fn walk_enum_def<'v, V: Visitor<'v>>(
+    visitor: &mut V,
+    enum_definition: &'v EnumDef<'v>,
+    item_id: HirId,
+) {
+    visitor.visit_id(item_id);
+    walk_list!(visitor, visit_variant, enum_definition.variants);
+}
+
+pub fn walk_variant<'v, V: Visitor<'v>>(visitor: &mut V, variant: &'v Variant<'v>) {
+    visitor.visit_ident(variant.ident);
+    visitor.visit_id(variant.id);
+    visitor.visit_variant_data(&variant.data);
+    walk_list!(visitor, visit_anon_const, &variant.disr_expr);
+}
+
+pub fn walk_label<'v, V: Visitor<'v>>(visitor: &mut V, label: &'v Label) {
+    visitor.visit_ident(label.ident);
+}
+
+pub fn walk_inf<'v, V: Visitor<'v>>(visitor: &mut V, inf: &'v InferArg) {
+    visitor.visit_id(inf.hir_id);
+}
+
+pub fn walk_generic_arg<'v, V: Visitor<'v>>(visitor: &mut V, generic_arg: &'v GenericArg<'v>) {
+    match generic_arg {
+        GenericArg::Lifetime(lt) => visitor.visit_lifetime(lt),
+        GenericArg::Type(ty) => visitor.visit_ty(ty),
+        GenericArg::Const(ct) => visitor.visit_anon_const(&ct.value),
+        GenericArg::Infer(inf) => visitor.visit_infer(inf),
+    }
+}
+
+pub fn walk_lifetime<'v, V: Visitor<'v>>(visitor: &mut V, lifetime: &'v Lifetime) {
+    visitor.visit_id(lifetime.hir_id);
+    match lifetime.name {
+        LifetimeName::Param(_, ParamName::Plain(ident)) => {
+            visitor.visit_ident(ident);
+        }
+        LifetimeName::Param(_, ParamName::Fresh)
+        | LifetimeName::Param(_, ParamName::Error)
+        | LifetimeName::Static
+        | LifetimeName::Error
+        | LifetimeName::ImplicitObjectLifetimeDefault
+        | LifetimeName::Infer => {}
+    }
+}
+
+pub fn walk_qpath<'v, V: Visitor<'v>>(visitor: &mut V, qpath: &'v QPath<'v>, id: HirId) {
+    match *qpath {
+        QPath::Resolved(ref maybe_qself, ref path) => {
+            walk_list!(visitor, visit_ty, maybe_qself);
+            visitor.visit_path(path, id)
+        }
+        QPath::TypeRelative(ref qself, ref segment) => {
+            visitor.visit_ty(qself);
+            visitor.visit_path_segment(segment);
+        }
+        QPath::LangItem(..) => {}
+    }
+}
+
+pub fn walk_path<'v, V: Visitor<'v>>(visitor: &mut V, path: &'v Path<'v>) {
+    for segment in path.segments {
+        visitor.visit_path_segment(segment);
+    }
+}
+
+pub fn walk_path_segment<'v, V: Visitor<'v>>(visitor: &mut V, segment: &'v PathSegment<'v>) {
+    visitor.visit_ident(segment.ident);
+    visitor.visit_id(segment.hir_id);
+    if let Some(ref args) = segment.args {
+        visitor.visit_generic_args(args);
+    }
+}
+
+pub fn walk_generic_args<'v, V: Visitor<'v>>(visitor: &mut V, generic_args: &'v GenericArgs<'v>) {
+    walk_list!(visitor, visit_generic_arg, generic_args.args);
+    walk_list!(visitor, visit_assoc_type_binding, generic_args.bindings);
+}
+
+pub fn walk_assoc_type_binding<'v, V: Visitor<'v>>(
+    visitor: &mut V,
+    type_binding: &'v TypeBinding<'v>,
+) {
+    visitor.visit_id(type_binding.hir_id);
+    visitor.visit_ident(type_binding.ident);
+    visitor.visit_generic_args(type_binding.gen_args);
+    match type_binding.kind {
+        TypeBindingKind::Equality { ref term } => match term {
+            Term::Ty(ref ty) => visitor.visit_ty(ty),
+            Term::Const(ref c) => visitor.visit_anon_const(c),
+        },
+        TypeBindingKind::Constraint { bounds } => walk_list!(visitor, visit_param_bound, bounds),
+    }
 }
 
 pub fn walk_associated_item_kind<'v, V: Visitor<'v>>(_: &mut V, _: &'v AssocItemKind) {
@@ -1198,3 +1181,27 @@ pub fn walk_defaultness<'v, V: Visitor<'v>>(_: &mut V, _: &'v Defaultness) {
     // the right thing to do, should content be added in the future,
     // would be to walk it.
 }
+
+pub fn walk_inline_asm<'v, V: Visitor<'v>>(visitor: &mut V, asm: &'v InlineAsm<'v>, id: HirId) {
+    for (op, op_sp) in asm.operands {
+        match op {
+            InlineAsmOperand::In { expr, .. } | InlineAsmOperand::InOut { expr, .. } => {
+                visitor.visit_expr(expr)
+            }
+            InlineAsmOperand::Out { expr, .. } => {
+                if let Some(expr) = expr {
+                    visitor.visit_expr(expr);
+                }
+            }
+            InlineAsmOperand::SplitInOut { in_expr, out_expr, .. } => {
+                visitor.visit_expr(in_expr);
+                if let Some(out_expr) = out_expr {
+                    visitor.visit_expr(out_expr);
+                }
+            }
+            InlineAsmOperand::Const { anon_const, .. }
+            | InlineAsmOperand::SymFn { anon_const, .. } => visitor.visit_anon_const(anon_const),
+            InlineAsmOperand::SymStatic { path, .. } => visitor.visit_qpath(path, id, *op_sp),
+        }
+    }
+}
diff --git a/compiler/rustc_hir/src/lang_items.rs b/compiler/rustc_hir/src/lang_items.rs
index ca615a4912a1..a55224d10972 100644
--- a/compiler/rustc_hir/src/lang_items.rs
+++ b/compiler/rustc_hir/src/lang_items.rs
@@ -12,35 +12,56 @@ use crate::errors::LangItemError;
 use crate::{MethodKind, Target};
 
 use rustc_ast as ast;
-use rustc_data_structures::fx::FxIndexMap;
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_macros::HashStable_Generic;
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_span::Span;
 
-use std::sync::LazyLock;
-
-pub enum LangItemGroup {
-    Op,
-    Fn,
+/// All of the language items, defined or not.
+/// Defined lang items can come from the current crate or its dependencies.
+#[derive(HashStable_Generic, Debug)]
+pub struct LanguageItems {
+    /// Mappings from lang items to their possibly found [`DefId`]s.
+    /// The index corresponds to the order in [`LangItem`].
+    items: [Option<DefId>; std::mem::variant_count::<LangItem>()],
+    /// Lang items that were not found during collection.
+    pub missing: Vec<LangItem>,
 }
 
-const NUM_GROUPS: usize = 2;
+impl LanguageItems {
+    /// Construct an empty collection of lang items and no missing ones.
+    pub fn new() -> Self {
+        Self { items: [None; std::mem::variant_count::<LangItem>()], missing: Vec::new() }
+    }
 
-macro_rules! expand_group {
-    () => {
-        None
-    };
-    ($group:expr) => {
-        Some($group)
-    };
+    pub fn get(&self, item: LangItem) -> Option<DefId> {
+        self.items[item as usize]
+    }
+
+    pub fn set(&mut self, item: LangItem, def_id: DefId) {
+        self.items[item as usize] = Some(def_id);
+    }
+
+    /// Requires that a given `LangItem` was bound and returns the corresponding `DefId`.
+    /// If it wasn't bound, e.g. due to a missing `#[lang = "<it.name()>"]`,
+    /// returns an error encapsulating the `LangItem`.
+    pub fn require(&self, it: LangItem) -> Result<DefId, LangItemError> {
+        self.get(it).ok_or_else(|| LangItemError(it))
+    }
+
+    pub fn iter<'a>(&'a self) -> impl Iterator<Item = (LangItem, DefId)> + 'a {
+        self.items
+            .iter()
+            .enumerate()
+            .filter_map(|(i, id)| id.map(|id| (LangItem::from_u32(i as u32).unwrap(), id)))
+    }
 }
 
 // The actual lang items defined come at the end of this file in one handy table.
 // So you probably just want to nip down to the end.
 macro_rules! language_item_table {
     (
-        $( $(#[$attr:meta])* $variant:ident $($group:expr)?, $module:ident :: $name:ident, $method:ident, $target:expr, $generics:expr; )*
+        $( $(#[$attr:meta])* $variant:ident, $module:ident :: $name:ident, $method:ident, $target:expr, $generics:expr; )*
     ) => {
 
         enum_from_u32! {
@@ -66,12 +87,17 @@ macro_rules! language_item_table {
                 }
             }
 
-            /// The [group](LangItemGroup) that this lang item belongs to,
-            /// or `None` if it doesn't belong to a group.
-            pub fn group(self) -> Option<LangItemGroup> {
-                use LangItemGroup::*;
+            /// Opposite of [`LangItem::name`]
+            pub fn from_name(name: Symbol) -> Option<Self> {
+                match name {
+                    $( $module::$name => Some(LangItem::$variant), )*
+                    _ => None,
+                }
+            }
+
+            pub fn target(self) -> Target {
                 match self {
-                    $( LangItem::$variant => expand_group!($($group)*), )*
+                    $( LangItem::$variant => $target, )*
                 }
             }
 
@@ -82,50 +108,7 @@ macro_rules! language_item_table {
             }
         }
 
-        /// All of the language items, defined or not.
-        /// Defined lang items can come from the current crate or its dependencies.
-        #[derive(HashStable_Generic, Debug)]
-        pub struct LanguageItems {
-            /// Mappings from lang items to their possibly found [`DefId`]s.
-            /// The index corresponds to the order in [`LangItem`].
-            pub items: Vec<Option<DefId>>,
-            /// Lang items that were not found during collection.
-            pub missing: Vec<LangItem>,
-            /// Mapping from [`LangItemGroup`] discriminants to all
-            /// [`DefId`]s of lang items in that group.
-            pub groups: [Vec<DefId>; NUM_GROUPS],
-        }
-
         impl LanguageItems {
-            /// Construct an empty collection of lang items and no missing ones.
-            pub fn new() -> Self {
-                fn init_none(_: LangItem) -> Option<DefId> { None }
-                const EMPTY: Vec<DefId> = Vec::new();
-
-                Self {
-                    items: vec![$(init_none(LangItem::$variant)),*],
-                    missing: Vec::new(),
-                    groups: [EMPTY; NUM_GROUPS],
-                }
-            }
-
-            /// Returns the mappings to the possibly found `DefId`s for each lang item.
-            pub fn items(&self) -> &[Option<DefId>] {
-                &*self.items
-            }
-
-            /// Requires that a given `LangItem` was bound and returns the corresponding `DefId`.
-            /// If it wasn't bound, e.g. due to a missing `#[lang = "<it.name()>"]`,
-            /// returns an error encapsulating the `LangItem`.
-            pub fn require(&self, it: LangItem) -> Result<DefId, LangItemError> {
-                self.items[it as usize].ok_or_else(|| LangItemError(it))
-            }
-
-            /// Returns the [`DefId`]s of all lang items in a group.
-            pub fn group(&self, group: LangItemGroup) -> &[DefId] {
-                self.groups[group as usize].as_ref()
-            }
-
             $(
                 #[doc = concat!("Returns the [`DefId`] of the `", stringify!($name), "` lang item if it is defined.")]
                 pub fn $method(&self) -> Option<DefId> {
@@ -133,15 +116,6 @@ macro_rules! language_item_table {
                 }
             )*
         }
-
-        /// A mapping from the name of the lang item to its order and the form it must be of.
-        pub static ITEM_REFS: LazyLock<FxIndexMap<Symbol, (usize, Target)>> = LazyLock::new(|| {
-            let mut item_refs = FxIndexMap::default();
-            $( item_refs.insert($module::$name, (LangItem::$variant as usize, $target)); )*
-            item_refs
-        });
-
-// End of the macro
     }
 }
 
@@ -152,14 +126,12 @@ impl<CTX> HashStable<CTX> for LangItem {
 }
 
 /// Extracts the first `lang = "$name"` out of a list of attributes.
-/// The attributes `#[panic_handler]` and `#[alloc_error_handler]`
-/// are also extracted out when found.
+/// The `#[panic_handler]` attribute is also extracted out when found.
 pub fn extract(attrs: &[ast::Attribute]) -> Option<(Symbol, Span)> {
     attrs.iter().find_map(|attr| {
         Some(match attr {
             _ if attr.has_name(sym::lang) => (attr.value_str()?, attr.span),
             _ if attr.has_name(sym::panic_handler) => (sym::panic_impl, attr.span),
-            _ if attr.has_name(sym::alloc_error_handler) => (sym::oom, attr.span),
             _ => return None,
         })
     })
@@ -196,30 +168,30 @@ language_item_table! {
     TransmuteOpts,           sym::transmute_opts,      transmute_opts,             Target::Struct,         GenericRequirement::Exact(0);
     TransmuteTrait,          sym::transmute_trait,     transmute_trait,            Target::Trait,          GenericRequirement::Exact(3);
 
-    Add(Op),                 sym::add,                 add_trait,                  Target::Trait,          GenericRequirement::Exact(1);
-    Sub(Op),                 sym::sub,                 sub_trait,                  Target::Trait,          GenericRequirement::Exact(1);
-    Mul(Op),                 sym::mul,                 mul_trait,                  Target::Trait,          GenericRequirement::Exact(1);
-    Div(Op),                 sym::div,                 div_trait,                  Target::Trait,          GenericRequirement::Exact(1);
-    Rem(Op),                 sym::rem,                 rem_trait,                  Target::Trait,          GenericRequirement::Exact(1);
-    Neg(Op),                 sym::neg,                 neg_trait,                  Target::Trait,          GenericRequirement::Exact(0);
-    Not(Op),                 sym::not,                 not_trait,                  Target::Trait,          GenericRequirement::Exact(0);
-    BitXor(Op),              sym::bitxor,              bitxor_trait,               Target::Trait,          GenericRequirement::Exact(1);
-    BitAnd(Op),              sym::bitand,              bitand_trait,               Target::Trait,          GenericRequirement::Exact(1);
-    BitOr(Op),               sym::bitor,               bitor_trait,                Target::Trait,          GenericRequirement::Exact(1);
-    Shl(Op),                 sym::shl,                 shl_trait,                  Target::Trait,          GenericRequirement::Exact(1);
-    Shr(Op),                 sym::shr,                 shr_trait,                  Target::Trait,          GenericRequirement::Exact(1);
-    AddAssign(Op),           sym::add_assign,          add_assign_trait,           Target::Trait,          GenericRequirement::Exact(1);
-    SubAssign(Op),           sym::sub_assign,          sub_assign_trait,           Target::Trait,          GenericRequirement::Exact(1);
-    MulAssign(Op),           sym::mul_assign,          mul_assign_trait,           Target::Trait,          GenericRequirement::Exact(1);
-    DivAssign(Op),           sym::div_assign,          div_assign_trait,           Target::Trait,          GenericRequirement::Exact(1);
-    RemAssign(Op),           sym::rem_assign,          rem_assign_trait,           Target::Trait,          GenericRequirement::Exact(1);
-    BitXorAssign(Op),        sym::bitxor_assign,       bitxor_assign_trait,        Target::Trait,          GenericRequirement::Exact(1);
-    BitAndAssign(Op),        sym::bitand_assign,       bitand_assign_trait,        Target::Trait,          GenericRequirement::Exact(1);
-    BitOrAssign(Op),         sym::bitor_assign,        bitor_assign_trait,         Target::Trait,          GenericRequirement::Exact(1);
-    ShlAssign(Op),           sym::shl_assign,          shl_assign_trait,           Target::Trait,          GenericRequirement::Exact(1);
-    ShrAssign(Op),           sym::shr_assign,          shr_assign_trait,           Target::Trait,          GenericRequirement::Exact(1);
-    Index(Op),               sym::index,               index_trait,                Target::Trait,          GenericRequirement::Exact(1);
-    IndexMut(Op),            sym::index_mut,           index_mut_trait,            Target::Trait,          GenericRequirement::Exact(1);
+    Add,                     sym::add,                 add_trait,                  Target::Trait,          GenericRequirement::Exact(1);
+    Sub,                     sym::sub,                 sub_trait,                  Target::Trait,          GenericRequirement::Exact(1);
+    Mul,                     sym::mul,                 mul_trait,                  Target::Trait,          GenericRequirement::Exact(1);
+    Div,                     sym::div,                 div_trait,                  Target::Trait,          GenericRequirement::Exact(1);
+    Rem,                     sym::rem,                 rem_trait,                  Target::Trait,          GenericRequirement::Exact(1);
+    Neg,                     sym::neg,                 neg_trait,                  Target::Trait,          GenericRequirement::Exact(0);
+    Not,                     sym::not,                 not_trait,                  Target::Trait,          GenericRequirement::Exact(0);
+    BitXor,                  sym::bitxor,              bitxor_trait,               Target::Trait,          GenericRequirement::Exact(1);
+    BitAnd,                  sym::bitand,              bitand_trait,               Target::Trait,          GenericRequirement::Exact(1);
+    BitOr,                   sym::bitor,               bitor_trait,                Target::Trait,          GenericRequirement::Exact(1);
+    Shl,                     sym::shl,                 shl_trait,                  Target::Trait,          GenericRequirement::Exact(1);
+    Shr,                     sym::shr,                 shr_trait,                  Target::Trait,          GenericRequirement::Exact(1);
+    AddAssign,               sym::add_assign,          add_assign_trait,           Target::Trait,          GenericRequirement::Exact(1);
+    SubAssign,               sym::sub_assign,          sub_assign_trait,           Target::Trait,          GenericRequirement::Exact(1);
+    MulAssign,               sym::mul_assign,          mul_assign_trait,           Target::Trait,          GenericRequirement::Exact(1);
+    DivAssign,               sym::div_assign,          div_assign_trait,           Target::Trait,          GenericRequirement::Exact(1);
+    RemAssign,               sym::rem_assign,          rem_assign_trait,           Target::Trait,          GenericRequirement::Exact(1);
+    BitXorAssign,            sym::bitxor_assign,       bitxor_assign_trait,        Target::Trait,          GenericRequirement::Exact(1);
+    BitAndAssign,            sym::bitand_assign,       bitand_assign_trait,        Target::Trait,          GenericRequirement::Exact(1);
+    BitOrAssign,             sym::bitor_assign,        bitor_assign_trait,         Target::Trait,          GenericRequirement::Exact(1);
+    ShlAssign,               sym::shl_assign,          shl_assign_trait,           Target::Trait,          GenericRequirement::Exact(1);
+    ShrAssign,               sym::shr_assign,          shr_assign_trait,           Target::Trait,          GenericRequirement::Exact(1);
+    Index,                   sym::index,               index_trait,                Target::Trait,          GenericRequirement::Exact(1);
+    IndexMut,                sym::index_mut,           index_mut_trait,            Target::Trait,          GenericRequirement::Exact(1);
 
     UnsafeCell,              sym::unsafe_cell,         unsafe_cell_type,           Target::Struct,         GenericRequirement::None;
     VaList,                  sym::va_list,             va_list,                    Target::Struct,         GenericRequirement::None;
@@ -229,9 +201,9 @@ language_item_table! {
     DerefTarget,             sym::deref_target,        deref_target,               Target::AssocTy,        GenericRequirement::None;
     Receiver,                sym::receiver,            receiver_trait,             Target::Trait,          GenericRequirement::None;
 
-    Fn(Fn),                  kw::Fn,                   fn_trait,                   Target::Trait,          GenericRequirement::Exact(1);
-    FnMut(Fn),               sym::fn_mut,              fn_mut_trait,               Target::Trait,          GenericRequirement::Exact(1);
-    FnOnce(Fn),              sym::fn_once,             fn_once_trait,              Target::Trait,          GenericRequirement::Exact(1);
+    Fn,                      kw::Fn,                   fn_trait,                   Target::Trait,          GenericRequirement::Exact(1);
+    FnMut,                   sym::fn_mut,              fn_mut_trait,               Target::Trait,          GenericRequirement::Exact(1);
+    FnOnce,                  sym::fn_once,             fn_once_trait,              Target::Trait,          GenericRequirement::Exact(1);
 
     FnOnceOutput,            sym::fn_once_output,      fn_once_output,             Target::AssocTy,        GenericRequirement::None;
 
@@ -241,8 +213,8 @@ language_item_table! {
     Unpin,                   sym::unpin,               unpin_trait,                Target::Trait,          GenericRequirement::None;
     Pin,                     sym::pin,                 pin_type,                   Target::Struct,         GenericRequirement::None;
 
-    PartialEq(Op),           sym::eq,                  eq_trait,                   Target::Trait,          GenericRequirement::Exact(1);
-    PartialOrd(Op),          sym::partial_ord,         partial_ord_trait,          Target::Trait,          GenericRequirement::Exact(1);
+    PartialEq,               sym::eq,                  eq_trait,                   Target::Trait,          GenericRequirement::Exact(1);
+    PartialOrd,              sym::partial_ord,         partial_ord_trait,          Target::Trait,          GenericRequirement::Exact(1);
 
     // A number of panic-related lang items. The `panic` item corresponds to divide-by-zero and
     // various panic cases with `match`. The `panic_bounds_check` item is for indexing arrays.
@@ -266,7 +238,6 @@ language_item_table! {
     ExchangeMalloc,          sym::exchange_malloc,     exchange_malloc_fn,         Target::Fn,             GenericRequirement::None;
     BoxFree,                 sym::box_free,            box_free_fn,                Target::Fn,             GenericRequirement::Minimum(1);
     DropInPlace,             sym::drop_in_place,       drop_in_place_fn,           Target::Fn,             GenericRequirement::Minimum(1);
-    Oom,                     sym::oom,                 oom,                        Target::Fn,             GenericRequirement::None;
     AllocLayout,             sym::alloc_layout,        alloc_layout,               Target::Struct,         GenericRequirement::None;
 
     Start,                   sym::start,               start_fn,                   Target::Fn,             GenericRequirement::Exact(1);
@@ -338,3 +309,34 @@ pub enum GenericRequirement {
     Minimum(usize),
     Exact(usize),
 }
+
+pub static FN_TRAITS: &'static [LangItem] = &[LangItem::Fn, LangItem::FnMut, LangItem::FnOnce];
+
+pub static OPERATORS: &'static [LangItem] = &[
+    LangItem::Add,
+    LangItem::Sub,
+    LangItem::Mul,
+    LangItem::Div,
+    LangItem::Rem,
+    LangItem::Neg,
+    LangItem::Not,
+    LangItem::BitXor,
+    LangItem::BitAnd,
+    LangItem::BitOr,
+    LangItem::Shl,
+    LangItem::Shr,
+    LangItem::AddAssign,
+    LangItem::SubAssign,
+    LangItem::MulAssign,
+    LangItem::DivAssign,
+    LangItem::RemAssign,
+    LangItem::BitXorAssign,
+    LangItem::BitAndAssign,
+    LangItem::BitOrAssign,
+    LangItem::ShlAssign,
+    LangItem::ShrAssign,
+    LangItem::Index,
+    LangItem::IndexMut,
+    LangItem::PartialEq,
+    LangItem::PartialOrd,
+];
diff --git a/compiler/rustc_hir/src/lib.rs b/compiler/rustc_hir/src/lib.rs
index 1c4aa420c9bf..1c55cd8fee8f 100644
--- a/compiler/rustc_hir/src/lib.rs
+++ b/compiler/rustc_hir/src/lib.rs
@@ -5,10 +5,10 @@
 #![feature(associated_type_defaults)]
 #![feature(closure_track_caller)]
 #![feature(const_btree_len)]
-#![feature(once_cell)]
 #![feature(min_specialization)]
 #![feature(never_type)]
 #![feature(rustc_attrs)]
+#![feature(variant_count)]
 #![recursion_limit = "256"]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
diff --git a/compiler/rustc_hir/src/stable_hash_impls.rs b/compiler/rustc_hir/src/stable_hash_impls.rs
index 06b7a65662e7..23423e8f3b3b 100644
--- a/compiler/rustc_hir/src/stable_hash_impls.rs
+++ b/compiler/rustc_hir/src/stable_hash_impls.rs
@@ -49,7 +49,7 @@ impl<HirCtx: crate::HashStableContext> ToStableHashKey<HirCtx> for ItemId {
 
     #[inline]
     fn to_stable_hash_key(&self, hcx: &HirCtx) -> DefPathHash {
-        self.def_id.def_id.to_stable_hash_key(hcx)
+        self.owner_id.def_id.to_stable_hash_key(hcx)
     }
 }
 
@@ -58,7 +58,7 @@ impl<HirCtx: crate::HashStableContext> ToStableHashKey<HirCtx> for TraitItemId {
 
     #[inline]
     fn to_stable_hash_key(&self, hcx: &HirCtx) -> DefPathHash {
-        self.def_id.def_id.to_stable_hash_key(hcx)
+        self.owner_id.def_id.to_stable_hash_key(hcx)
     }
 }
 
@@ -67,7 +67,7 @@ impl<HirCtx: crate::HashStableContext> ToStableHashKey<HirCtx> for ImplItemId {
 
     #[inline]
     fn to_stable_hash_key(&self, hcx: &HirCtx) -> DefPathHash {
-        self.def_id.def_id.to_stable_hash_key(hcx)
+        self.owner_id.def_id.to_stable_hash_key(hcx)
     }
 }
 
@@ -76,7 +76,7 @@ impl<HirCtx: crate::HashStableContext> ToStableHashKey<HirCtx> for ForeignItemId
 
     #[inline]
     fn to_stable_hash_key(&self, hcx: &HirCtx) -> DefPathHash {
-        self.def_id.def_id.to_stable_hash_key(hcx)
+        self.owner_id.def_id.to_stable_hash_key(hcx)
     }
 }
 
diff --git a/compiler/rustc_hir/src/weak_lang_items.rs b/compiler/rustc_hir/src/weak_lang_items.rs
index da9c9c1216e9..0cc50c6dd850 100644
--- a/compiler/rustc_hir/src/weak_lang_items.rs
+++ b/compiler/rustc_hir/src/weak_lang_items.rs
@@ -1,53 +1,30 @@
 //! Validity checking for weak lang items
 
-use crate::def_id::DefId;
-use crate::{lang_items, LangItem, LanguageItems};
+use crate::LangItem;
 
-use rustc_ast as ast;
-use rustc_data_structures::fx::FxIndexMap;
 use rustc_span::symbol::{sym, Symbol};
 
-use std::sync::LazyLock;
-
 macro_rules! weak_lang_items {
-    ($($name:ident, $item:ident, $sym:ident;)*) => (
+    ($($item:ident, $sym:ident;)*) => {
+        pub static WEAK_LANG_ITEMS: &[LangItem] = &[$(LangItem::$item,)*];
 
-pub static WEAK_ITEMS_REFS: LazyLock<FxIndexMap<Symbol, LangItem>> = LazyLock::new(|| {
-    let mut map = FxIndexMap::default();
-    $(map.insert(sym::$name, LangItem::$item);)*
-    map
-});
+        impl LangItem {
+            pub fn is_weak(self) -> bool {
+                matches!(self, $(LangItem::$item)|*)
+            }
 
-pub static WEAK_ITEMS_SYMBOLS: LazyLock<FxIndexMap<LangItem, Symbol>> = LazyLock::new(|| {
-    let mut map = FxIndexMap::default();
-    $(map.insert(LangItem::$item, sym::$sym);)*
-    map
-});
-
-pub fn link_name(attrs: &[ast::Attribute]) -> Option<Symbol>
-{
-    lang_items::extract(attrs).and_then(|(name, _)| {
-        $(if name == sym::$name {
-            Some(sym::$sym)
-        } else)* {
-            None
+            pub fn link_name(self) -> Option<Symbol> {
+                match self {
+                    $( LangItem::$item => Some(sym::$sym),)*
+                    _ => None,
+                }
+            }
         }
-    })
-}
-
-impl LanguageItems {
-    pub fn is_weak_lang_item(&self, item_def_id: DefId) -> bool {
-        let did = Some(item_def_id);
-
-        $(self.$name() == did)||*
     }
 }
 
-) }
-
 weak_lang_items! {
-    panic_impl,         PanicImpl,          rust_begin_unwind;
-    eh_personality,     EhPersonality,      rust_eh_personality;
-    eh_catch_typeinfo,  EhCatchTypeinfo,    rust_eh_catch_typeinfo;
-    oom,                Oom,                rust_oom;
+    PanicImpl,          rust_begin_unwind;
+    EhPersonality,      rust_eh_personality;
+    EhCatchTypeinfo,    rust_eh_catch_typeinfo;
 }
diff --git a/compiler/rustc_hir_analysis/src/astconv/errors.rs b/compiler/rustc_hir_analysis/src/astconv/errors.rs
index a9152bdc5978..e6465d641f1e 100644
--- a/compiler/rustc_hir_analysis/src/astconv/errors.rs
+++ b/compiler/rustc_hir_analysis/src/astconv/errors.rs
@@ -177,11 +177,8 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
             .all_traits()
             .filter(|trait_def_id| {
                 let viz = self.tcx().visibility(*trait_def_id);
-                if let Some(def_id) = self.item_def_id() {
-                    viz.is_accessible_from(def_id, self.tcx())
-                } else {
-                    viz.is_visible_locally()
-                }
+                let def_id = self.item_def_id();
+                viz.is_accessible_from(def_id, self.tcx())
             })
             .collect();
 
diff --git a/compiler/rustc_hir_analysis/src/astconv/mod.rs b/compiler/rustc_hir_analysis/src/astconv/mod.rs
index a0350c26d827..4518cf30acdd 100644
--- a/compiler/rustc_hir_analysis/src/astconv/mod.rs
+++ b/compiler/rustc_hir_analysis/src/astconv/mod.rs
@@ -23,7 +23,6 @@ use rustc_hir as hir;
 use rustc_hir::def::{CtorOf, DefKind, Namespace, Res};
 use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_hir::intravisit::{walk_generics, Visitor as _};
-use rustc_hir::lang_items::LangItem;
 use rustc_hir::{GenericArg, GenericArgs, OpaqueTyOrigin};
 use rustc_middle::middle::stability::AllowUnstable;
 use rustc_middle::ty::subst::{self, GenericArgKind, InternalSubsts, SubstsRef};
@@ -36,7 +35,7 @@ use rustc_session::lint::builtin::{AMBIGUOUS_ASSOCIATED_ITEMS, BARE_TRAIT_OBJECT
 use rustc_span::edition::Edition;
 use rustc_span::lev_distance::find_best_match_for_name;
 use rustc_span::symbol::{kw, Ident, Symbol};
-use rustc_span::Span;
+use rustc_span::{sym, Span};
 use rustc_target::spec::abi;
 use rustc_trait_selection::traits;
 use rustc_trait_selection::traits::astconv_object_safety_violations;
@@ -55,7 +54,7 @@ pub struct PathSeg(pub DefId, pub usize);
 pub trait AstConv<'tcx> {
     fn tcx<'a>(&'a self) -> TyCtxt<'tcx>;
 
-    fn item_def_id(&self) -> Option<DefId>;
+    fn item_def_id(&self) -> DefId;
 
     /// Returns predicates in scope of the form `X: Foo<T>`, where `X`
     /// is a type parameter `X` with the given id `def_id` and T
@@ -275,6 +274,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
             item_segment.args(),
             item_segment.infer_args,
             None,
+            ty::BoundConstness::NotConst,
         );
         if let Some(b) = item_segment.args().bindings.first() {
             Self::prohibit_assoc_ty_binding(self.tcx(), b.span);
@@ -324,6 +324,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
         generic_args: &'a hir::GenericArgs<'_>,
         infer_args: bool,
         self_ty: Option<Ty<'tcx>>,
+        constness: ty::BoundConstness,
     ) -> (SubstsRef<'tcx>, GenericArgCountResult) {
         // If the type is parameterized by this region, then replace this
         // region with the current anon region binding (in other words,
@@ -499,6 +500,9 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                     }
                     GenericParamDefKind::Const { has_default } => {
                         let ty = tcx.at(self.span).type_of(param.def_id);
+                        if ty.references_error() {
+                            return tcx.const_error(ty).into();
+                        }
                         if !infer_args && has_default {
                             tcx.bound_const_param_default(param.def_id)
                                 .subst(tcx, substs.unwrap())
@@ -534,6 +538,12 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
             &mut substs_ctx,
         );
 
+        if let ty::BoundConstness::ConstIfConst = constness
+            && generics.has_self && !tcx.has_attr(def_id, sym::const_trait)
+        {
+            tcx.sess.emit_err(crate::errors::ConstBoundForNonConstTrait { span } );
+        }
+
         (substs, arg_count)
     }
 
@@ -601,6 +611,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
             item_segment.args(),
             item_segment.infer_args,
             None,
+            ty::BoundConstness::NotConst,
         );
 
         if let Some(b) = item_segment.args().bindings.first() {
@@ -620,6 +631,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
         &self,
         trait_ref: &hir::TraitRef<'_>,
         self_ty: Ty<'tcx>,
+        constness: ty::BoundConstness,
     ) -> ty::TraitRef<'tcx> {
         self.prohibit_generics(trait_ref.path.segments.split_last().unwrap().1.iter(), |_| {});
 
@@ -629,6 +641,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
             self_ty,
             trait_ref.path.segments.last().unwrap(),
             true,
+            constness,
         )
     }
 
@@ -655,6 +668,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
             args,
             infer_args,
             Some(self_ty),
+            constness,
         );
 
         let tcx = self.tcx();
@@ -680,6 +694,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                 speculative,
                 &mut dup_bindings,
                 binding_span.unwrap_or(binding.span),
+                constness,
             );
             // Okay to ignore `Err` because of `ErrorGuaranteed` (see above).
         }
@@ -783,6 +798,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
         self_ty: Ty<'tcx>,
         trait_segment: &hir::PathSegment<'_>,
         is_impl: bool,
+        constness: ty::BoundConstness,
     ) -> ty::TraitRef<'tcx> {
         let (substs, _) = self.create_substs_for_ast_trait_ref(
             span,
@@ -790,6 +806,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
             self_ty,
             trait_segment,
             is_impl,
+            constness,
         );
         if let Some(b) = trait_segment.args().bindings.first() {
             Self::prohibit_assoc_ty_binding(self.tcx(), b.span);
@@ -805,6 +822,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
         self_ty: Ty<'tcx>,
         trait_segment: &'a hir::PathSegment<'a>,
         is_impl: bool,
+        constness: ty::BoundConstness,
     ) -> (SubstsRef<'tcx>, GenericArgCountResult) {
         self.complain_about_internal_fn_trait(span, trait_def_id, trait_segment, is_impl);
 
@@ -816,6 +834,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
             trait_segment.args(),
             trait_segment.infer_args,
             Some(self_ty),
+            constness,
         )
     }
 
@@ -867,9 +886,9 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
             }
         }
 
-        let sized_def_id = tcx.lang_items().require(LangItem::Sized);
+        let sized_def_id = tcx.lang_items().sized_trait();
         match (&sized_def_id, unbound) {
-            (Ok(sized_def_id), Some(tpb))
+            (Some(sized_def_id), Some(tpb))
                 if tpb.path.res == Res::Def(DefKind::Trait, *sized_def_id) =>
             {
                 // There was in fact a `?Sized` bound, return without doing anything
@@ -889,7 +908,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                 // There was no `?Sized` bound; add implicitly sized if `Sized` is available.
             }
         }
-        if sized_def_id.is_err() {
+        if sized_def_id.is_none() {
             // No lang item for `Sized`, so we can't add it as a bound.
             return;
         }
@@ -1027,6 +1046,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
         speculative: bool,
         dup_bindings: &mut FxHashMap<DefId, Span>,
         path_span: Span,
+        constness: ty::BoundConstness,
     ) -> Result<(), ErrorGuaranteed> {
         // Given something like `U: SomeTrait<T = X>`, we want to produce a
         // predicate like `<U as SomeTrait>::T = X`. This is somewhat
@@ -1122,10 +1142,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                 trait_ref.substs,
             );
 
-            debug!(
-                "add_predicates_for_ast_type_binding: substs for trait-ref and assoc_item: {:?}",
-                substs_trait_ref_and_assoc_item
-            );
+            debug!(?substs_trait_ref_and_assoc_item);
 
             ty::ProjectionTy {
                 item_def_id: assoc_item.def_id,
@@ -1146,8 +1163,8 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                     tcx.collect_constrained_late_bound_regions(&projection_ty);
                 let late_bound_in_ty =
                     tcx.collect_referenced_late_bound_regions(&trait_ref.rebind(ty));
-                debug!("late_bound_in_trait_ref = {:?}", late_bound_in_trait_ref);
-                debug!("late_bound_in_ty = {:?}", late_bound_in_ty);
+                debug!(?late_bound_in_trait_ref);
+                debug!(?late_bound_in_ty);
 
                 // FIXME: point at the type params that don't have appropriate lifetimes:
                 // struct S1<F: for<'a> Fn(&i32, &i32) -> &'a i32>(F);
@@ -1184,7 +1201,8 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                     (_, _) => {
                         let got = if let Some(_) = term.ty() { "type" } else { "constant" };
                         let expected = def_kind.descr(assoc_item_def_id);
-                        tcx.sess
+                        let reported = tcx
+                            .sess
                             .struct_span_err(
                                 binding.span,
                                 &format!("expected {expected} bound, found {got}"),
@@ -1195,11 +1213,14 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                             )
                             .emit();
                         term = match def_kind {
-                            hir::def::DefKind::AssocTy => tcx.ty_error().into(),
+                            hir::def::DefKind::AssocTy => {
+                                tcx.ty_error_with_guaranteed(reported).into()
+                            }
                             hir::def::DefKind::AssocConst => tcx
-                                .const_error(
+                                .const_error_with_guaranteed(
                                     tcx.bound_type_of(assoc_item_def_id)
                                         .subst(tcx, projection_ty.skip_binder().substs),
+                                    reported,
                                 )
                                 .into(),
                             _ => unreachable!(),
@@ -1317,8 +1338,9 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                 .map(|&(trait_ref, _, _)| trait_ref.def_id())
                 .find(|&trait_ref| tcx.is_trait_alias(trait_ref))
                 .map(|trait_ref| tcx.def_span(trait_ref));
-            tcx.sess.emit_err(TraitObjectDeclaredWithNoTraits { span, trait_alias_span });
-            return tcx.ty_error();
+            let reported =
+                tcx.sess.emit_err(TraitObjectDeclaredWithNoTraits { span, trait_alias_span });
+            return tcx.ty_error_with_guaranteed(reported);
         }
 
         // Check that there are no gross object safety violations;
@@ -1328,14 +1350,14 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
             let object_safety_violations =
                 astconv_object_safety_violations(tcx, item.trait_ref().def_id());
             if !object_safety_violations.is_empty() {
-                report_object_safety_error(
+                let reported = report_object_safety_error(
                     tcx,
                     span,
                     item.trait_ref().def_id(),
                     &object_safety_violations,
                 )
                 .emit();
-                return tcx.ty_error();
+                return tcx.ty_error_with_guaranteed(reported);
             }
         }
 
@@ -1648,6 +1670,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
 
     // Checks that `bounds` contains exactly one element and reports appropriate
     // errors otherwise.
+    #[instrument(level = "debug", skip(self, all_candidates, ty_param_name, is_equality), ret)]
     fn one_bound_for_assoc_type<I>(
         &self,
         all_candidates: impl Fn() -> I,
@@ -1677,10 +1700,10 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                 return Err(reported);
             }
         };
-        debug!("one_bound_for_assoc_type: bound = {:?}", bound);
+        debug!(?bound);
 
         if let Some(bound2) = next_cand {
-            debug!("one_bound_for_assoc_type: bound2 = {:?}", bound2);
+            debug!(?bound2);
 
             let is_equality = is_equality();
             let bounds = IntoIterator::into_iter([bound, bound2]).chain(matching_candidates);
@@ -1776,6 +1799,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
     // parameter or `Self`.
     // NOTE: When this function starts resolving `Trait::AssocTy` successfully
     // it should also start reporting the `BARE_TRAIT_OBJECTS` lint.
+    #[instrument(level = "debug", skip(self, hir_ref_id, span, qself, assoc_segment), fields(assoc_ident=?assoc_segment.ident), ret)]
     pub fn associated_path_to_ty(
         &self,
         hir_ref_id: hir::HirId,
@@ -1793,8 +1817,6 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
             Res::Err
         };
 
-        debug!("associated_path_to_ty: {:?}::{}", qself_ty, assoc_ident);
-
         // Check if we have an enum variant.
         let mut variant_resolution = None;
         if let ty::Adt(adt_def, _) = qself_ty.kind() {
@@ -1893,6 +1915,20 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                     }
                 }
             }
+
+            // see if we can satisfy using an inherent associated type
+            for impl_ in tcx.inherent_impls(adt_def.did()) {
+                let assoc_ty = tcx.associated_items(impl_).find_by_name_and_kind(
+                    tcx,
+                    assoc_ident,
+                    ty::AssocKind::Type,
+                    *impl_,
+                );
+                if let Some(assoc_ty) = assoc_ty {
+                    let ty = tcx.type_of(assoc_ty.def_id);
+                    return Ok((ty, DefKind::AssocTy, assoc_ty.def_id));
+                }
+            }
         }
 
         // Find the type of the associated item, and the trait where the associated
@@ -1962,7 +1998,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                     }
 
                     err.emit()
-                } else if let Some(reported) = qself_ty.error_reported() {
+                } else if let Err(reported) = qself_ty.error_reported() {
                     reported
                 } else {
                     // Don't print `TyErr` to the user.
@@ -2050,6 +2086,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
         item_def_id: DefId,
         trait_segment: &hir::PathSegment<'_>,
         item_segment: &hir::PathSegment<'_>,
+        constness: ty::BoundConstness,
     ) -> Ty<'tcx> {
         let tcx = self.tcx();
 
@@ -2064,17 +2101,14 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
 
             debug!("qpath_to_ty: self.item_def_id()={:?}", def_id);
 
-            let parent_def_id = def_id
-                .and_then(|def_id| {
-                    def_id.as_local().map(|def_id| tcx.hir().local_def_id_to_hir_id(def_id))
-                })
+            let parent_def_id = def_id.as_local().map(|def_id| tcx.hir().local_def_id_to_hir_id(def_id))
                 .map(|hir_id| tcx.hir().get_parent_item(hir_id).to_def_id());
 
             debug!("qpath_to_ty: parent_def_id={:?}", parent_def_id);
 
             // If the trait in segment is the same as the trait defining the item,
             // use the `<Self as ..>` syntax in the error.
-            let is_part_of_self_trait_constraints = def_id == Some(trait_def_id);
+            let is_part_of_self_trait_constraints = def_id == trait_def_id;
             let is_part_of_fn_in_self_trait = parent_def_id == Some(trait_def_id);
 
             let type_name = if is_part_of_self_trait_constraints || is_part_of_fn_in_self_trait {
@@ -2083,19 +2117,25 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                 "Type"
             };
 
-            self.report_ambiguous_associated_type(
+            let reported = self.report_ambiguous_associated_type(
                 span,
                 type_name,
                 &path_str,
                 item_segment.ident.name,
             );
-            return tcx.ty_error();
+            return tcx.ty_error_with_guaranteed(reported)
         };
 
         debug!("qpath_to_ty: self_type={:?}", self_ty);
 
-        let trait_ref =
-            self.ast_path_to_mono_trait_ref(span, trait_def_id, self_ty, trait_segment, false);
+        let trait_ref = self.ast_path_to_mono_trait_ref(
+            span,
+            trait_def_id,
+            self_ty,
+            trait_segment,
+            false,
+            constness,
+        );
 
         let item_substs = self.create_substs_for_associated_item(
             span,
@@ -2525,8 +2565,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                     {
                         err.span_note(impl_.self_ty.span, "not a concrete type");
                     }
-                    err.emit();
-                    tcx.ty_error()
+                    tcx.ty_error_with_guaranteed(err.emit())
                 } else {
                     self.normalize_ty(span, ty)
                 }
@@ -2534,12 +2573,19 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
             Res::Def(DefKind::AssocTy, def_id) => {
                 debug_assert!(path.segments.len() >= 2);
                 self.prohibit_generics(path.segments[..path.segments.len() - 2].iter(), |_| {});
+                // HACK: until we support `<Type as ~const Trait>`, assume all of them are.
+                let constness = if tcx.has_attr(tcx.parent(def_id), sym::const_trait) {
+                    ty::BoundConstness::ConstIfConst
+                } else {
+                    ty::BoundConstness::NotConst
+                };
                 self.qpath_to_ty(
                     span,
                     opt_self_ty,
                     def_id,
                     &path.segments[path.segments.len() - 2],
                     path.segments.last().unwrap(),
+                    constness,
                 )
             }
             Res::PrimTy(prim_ty) => {
@@ -2632,7 +2678,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
             }
             hir::TyKind::OpaqueDef(item_id, lifetimes, in_trait) => {
                 let opaque_ty = tcx.hir().item(item_id);
-                let def_id = item_id.def_id.to_def_id();
+                let def_id = item_id.owner_id.to_def_id();
 
                 match opaque_ty.kind {
                     hir::ItemKind::OpaqueTy(hir::OpaqueTy { origin, .. }) => {
@@ -2658,6 +2704,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                     &GenericArgs::none(),
                     true,
                     None,
+                    ty::BoundConstness::NotConst,
                 );
                 EarlyBinder(self.normalize_ty(span, tcx.at(span).type_of(def_id)))
                     .subst(tcx, substs)
@@ -2766,6 +2813,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
         }
     }
 
+    #[instrument(level = "debug", skip(self, hir_id, unsafety, abi, decl, generics, hir_ty), ret)]
     pub fn ty_of_fn(
         &self,
         hir_id: hir::HirId,
@@ -2775,8 +2823,6 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
         generics: Option<&hir::Generics<'_>>,
         hir_ty: Option<&hir::Ty<'_>>,
     ) -> ty::PolyFnSig<'tcx> {
-        debug!("ty_of_fn");
-
         let tcx = self.tcx();
         let bound_vars = tcx.late_bound_vars(hir_id);
         debug!(?bound_vars);
@@ -2826,7 +2872,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
             hir::FnRetTy::DefaultReturn(..) => tcx.mk_unit(),
         };
 
-        debug!("ty_of_fn: output_ty={:?}", output_ty);
+        debug!(?output_ty);
 
         let fn_ty = tcx.mk_fn_sig(input_tys.into_iter(), output_ty, decl.c_variadic, unsafety, abi);
         let bare_fn_ty = ty::Binder::bind_with_vars(fn_ty, bound_vars);
@@ -2903,8 +2949,11 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
         let hir::Node::Item(hir::Item { kind: hir::ItemKind::Impl(i), .. }) =
                 hir.get(hir.get_parent_node(fn_hir_id)) else { bug!("ImplItem should have Impl parent") };
 
-        let trait_ref =
-            self.instantiate_mono_trait_ref(i.of_trait.as_ref()?, self.ast_ty_to_ty(i.self_ty));
+        let trait_ref = self.instantiate_mono_trait_ref(
+            i.of_trait.as_ref()?,
+            self.ast_ty_to_ty(i.self_ty),
+            ty::BoundConstness::NotConst,
+        );
 
         let assoc = tcx.associated_items(trait_ref.def_id).find_by_name_and_kind(
             tcx,
@@ -2931,7 +2980,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
     ) {
         for br in referenced_regions.difference(&constrained_regions) {
             let br_name = match *br {
-                ty::BrNamed(_, kw::UnderscoreLifetime) | ty::BrAnon(_) | ty::BrEnv => {
+                ty::BrNamed(_, kw::UnderscoreLifetime) | ty::BrAnon(..) | ty::BrEnv => {
                     "an anonymous lifetime".to_string()
                 }
                 ty::BrNamed(_, name) => format!("lifetime `{}`", name),
@@ -2939,7 +2988,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
 
             let mut err = generate_err(&br_name);
 
-            if let ty::BrNamed(_, kw::UnderscoreLifetime) | ty::BrAnon(_) = *br {
+            if let ty::BrNamed(_, kw::UnderscoreLifetime) | ty::BrAnon(..) = *br {
                 // The only way for an anonymous lifetime to wind up
                 // in the return type but **also** be unconstrained is
                 // if it only appears in "associated types" in the
diff --git a/compiler/rustc_hir_analysis/src/check/check.rs b/compiler/rustc_hir_analysis/src/check/check.rs
index a1faf8025195..0ba5e6151012 100644
--- a/compiler/rustc_hir_analysis/src/check/check.rs
+++ b/compiler/rustc_hir_analysis/src/check/check.rs
@@ -6,7 +6,7 @@ use super::*;
 use rustc_attr as attr;
 use rustc_errors::{Applicability, ErrorGuaranteed, MultiSpan};
 use rustc_hir as hir;
-use rustc_hir::def::{DefKind, Res};
+use rustc_hir::def::{CtorKind, DefKind, Res};
 use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_hir::intravisit::Visitor;
 use rustc_hir::{ItemKind, Node, PathSegment};
@@ -26,6 +26,7 @@ use rustc_session::lint::builtin::{UNINHABITED_STATIC, UNSUPPORTED_CALLING_CONVE
 use rustc_span::symbol::sym;
 use rustc_span::{self, Span};
 use rustc_target::spec::abi::Abi;
+use rustc_trait_selection::traits::error_reporting::on_unimplemented::OnUnimplementedDirective;
 use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt as _;
 use rustc_trait_selection::traits::{self, ObligationCtxt};
 
@@ -75,7 +76,7 @@ fn check_struct(tcx: TyCtxt<'_>, def_id: LocalDefId) {
         check_simd(tcx, span, def_id);
     }
 
-    check_transparent(tcx, span, def);
+    check_transparent(tcx, def);
     check_packed(tcx, span, def);
 }
 
@@ -83,7 +84,7 @@ fn check_union(tcx: TyCtxt<'_>, def_id: LocalDefId) {
     let def = tcx.adt_def(def_id);
     let span = tcx.def_span(def_id);
     def.destructor(tcx); // force the destructor to be evaluated
-    check_transparent(tcx, span, def);
+    check_transparent(tcx, def);
     check_union_fields(tcx, span, def_id);
     check_packed(tcx, span, def);
 }
@@ -114,7 +115,7 @@ fn check_union_fields(tcx: TyCtxt<'_>, span: Span, item_def_id: LocalDefId) -> b
                 _ => {
                     // Fallback case: allow `ManuallyDrop` and things that are `Copy`.
                     ty.ty_adt_def().is_some_and(|adt_def| adt_def.is_manually_drop())
-                        || ty.is_copy_modulo_regions(tcx.at(span), param_env)
+                        || ty.is_copy_modulo_regions(tcx, param_env)
                 }
             }
         }
@@ -227,17 +228,17 @@ fn check_opaque<'tcx>(tcx: TyCtxt<'tcx>, id: hir::ItemId) {
         return;
     }
 
-    let substs = InternalSubsts::identity_for_item(tcx, item.def_id.to_def_id());
-    let span = tcx.def_span(item.def_id.def_id);
+    let substs = InternalSubsts::identity_for_item(tcx, item.owner_id.to_def_id());
+    let span = tcx.def_span(item.owner_id.def_id);
 
-    check_opaque_for_inheriting_lifetimes(tcx, item.def_id.def_id, span);
-    if tcx.type_of(item.def_id.def_id).references_error() {
+    check_opaque_for_inheriting_lifetimes(tcx, item.owner_id.def_id, span);
+    if tcx.type_of(item.owner_id.def_id).references_error() {
         return;
     }
-    if check_opaque_for_cycles(tcx, item.def_id.def_id, substs, span, &origin).is_err() {
+    if check_opaque_for_cycles(tcx, item.owner_id.def_id, substs, span, &origin).is_err() {
         return;
     }
-    check_opaque_meets_bounds(tcx, item.def_id.def_id, substs, span, &origin);
+    check_opaque_meets_bounds(tcx, item.owner_id.def_id, substs, span, &origin);
 }
 /// Checks that an opaque type does not use `Self` or `T::Foo` projections that would result
 /// in "inheriting lifetimes".
@@ -471,7 +472,7 @@ fn check_opaque_meets_bounds<'tcx>(
     // version.
     let errors = ocx.select_all_or_error();
     if !errors.is_empty() {
-        infcx.err_ctxt().report_fulfillment_errors(&errors, None, false);
+        infcx.err_ctxt().report_fulfillment_errors(&errors, None);
     }
     match origin {
         // Checked when type checking the function containing them.
@@ -492,25 +493,21 @@ fn check_opaque_meets_bounds<'tcx>(
 fn check_item_type<'tcx>(tcx: TyCtxt<'tcx>, id: hir::ItemId) {
     debug!(
         "check_item_type(it.def_id={:?}, it.name={})",
-        id.def_id,
-        tcx.def_path_str(id.def_id.to_def_id())
+        id.owner_id,
+        tcx.def_path_str(id.owner_id.to_def_id())
     );
     let _indenter = indenter();
-    match tcx.def_kind(id.def_id) {
+    match tcx.def_kind(id.owner_id) {
         DefKind::Static(..) => {
-            tcx.ensure().typeck(id.def_id.def_id);
-            maybe_check_static_with_link_section(tcx, id.def_id.def_id);
-            check_static_inhabited(tcx, id.def_id.def_id);
+            tcx.ensure().typeck(id.owner_id.def_id);
+            maybe_check_static_with_link_section(tcx, id.owner_id.def_id);
+            check_static_inhabited(tcx, id.owner_id.def_id);
         }
         DefKind::Const => {
-            tcx.ensure().typeck(id.def_id.def_id);
+            tcx.ensure().typeck(id.owner_id.def_id);
         }
         DefKind::Enum => {
-            let item = tcx.hir().item(id);
-            let hir::ItemKind::Enum(ref enum_definition, _) = item.kind else {
-                return;
-            };
-            check_enum(tcx, &enum_definition.variants, item.def_id.def_id);
+            check_enum(tcx, id.owner_id.def_id);
         }
         DefKind::Fn => {} // entirely within check_item_body
         DefKind::Impl => {
@@ -518,12 +515,12 @@ fn check_item_type<'tcx>(tcx: TyCtxt<'tcx>, id: hir::ItemId) {
             let hir::ItemKind::Impl(ref impl_) = it.kind else {
                 return;
             };
-            debug!("ItemKind::Impl {} with id {:?}", it.ident, it.def_id);
-            if let Some(impl_trait_ref) = tcx.impl_trait_ref(it.def_id) {
+            debug!("ItemKind::Impl {} with id {:?}", it.ident, it.owner_id);
+            if let Some(impl_trait_ref) = tcx.impl_trait_ref(it.owner_id) {
                 check_impl_items_against_trait(
                     tcx,
                     it.span,
-                    it.def_id.def_id,
+                    it.owner_id.def_id,
                     impl_trait_ref,
                     &impl_.items,
                 );
@@ -545,15 +542,15 @@ fn check_item_type<'tcx>(tcx: TyCtxt<'tcx>, id: hir::ItemId) {
                         fn_maybe_err(tcx, item.ident.span, abi);
                     }
                     hir::TraitItemKind::Type(.., Some(default)) => {
-                        let assoc_item = tcx.associated_item(item.def_id);
+                        let assoc_item = tcx.associated_item(item.owner_id);
                         let trait_substs =
-                            InternalSubsts::identity_for_item(tcx, it.def_id.to_def_id());
+                            InternalSubsts::identity_for_item(tcx, it.owner_id.to_def_id());
                         let _: Result<_, rustc_errors::ErrorGuaranteed> = check_type_bounds(
                             tcx,
                             assoc_item,
                             assoc_item,
                             default.span,
-                            ty::TraitRef { def_id: it.def_id.to_def_id(), substs: trait_substs },
+                            ty::TraitRef { def_id: it.owner_id.to_def_id(), substs: trait_substs },
                         );
                     }
                     _ => {}
@@ -561,16 +558,16 @@ fn check_item_type<'tcx>(tcx: TyCtxt<'tcx>, id: hir::ItemId) {
             }
         }
         DefKind::Struct => {
-            check_struct(tcx, id.def_id.def_id);
+            check_struct(tcx, id.owner_id.def_id);
         }
         DefKind::Union => {
-            check_union(tcx, id.def_id.def_id);
+            check_union(tcx, id.owner_id.def_id);
         }
         DefKind::OpaqueTy => {
             check_opaque(tcx, id);
         }
         DefKind::ImplTraitPlaceholder => {
-            let parent = tcx.impl_trait_in_trait_parent(id.def_id.to_def_id());
+            let parent = tcx.impl_trait_in_trait_parent(id.owner_id.to_def_id());
             // Only check the validity of this opaque type if the function has a default body
             if let hir::Node::TraitItem(hir::TraitItem {
                 kind: hir::TraitItemKind::Fn(_, hir::TraitFn::Provided(_)),
@@ -581,8 +578,8 @@ fn check_item_type<'tcx>(tcx: TyCtxt<'tcx>, id: hir::ItemId) {
             }
         }
         DefKind::TyAlias => {
-            let pty_ty = tcx.type_of(id.def_id);
-            let generics = tcx.generics_of(id.def_id);
+            let pty_ty = tcx.type_of(id.owner_id);
+            let generics = tcx.generics_of(id.owner_id);
             check_type_params_are_used(tcx, &generics, pty_ty);
         }
         DefKind::ForeignMod => {
@@ -604,7 +601,7 @@ fn check_item_type<'tcx>(tcx: TyCtxt<'tcx>, id: hir::ItemId) {
                 }
             } else {
                 for item in items {
-                    let def_id = item.id.def_id.def_id;
+                    let def_id = item.id.owner_id.def_id;
                     let generics = tcx.generics_of(def_id);
                     let own_counts = generics.own_counts();
                     if generics.params.len() - own_counts.lifetimes != 0 {
@@ -659,7 +656,7 @@ fn check_item_type<'tcx>(tcx: TyCtxt<'tcx>, id: hir::ItemId) {
 
 pub(super) fn check_on_unimplemented(tcx: TyCtxt<'_>, item: &hir::Item<'_>) {
     // an error would be reported if this fails.
-    let _ = traits::OnUnimplementedDirective::of_item(tcx, item.def_id.to_def_id());
+    let _ = OnUnimplementedDirective::of_item(tcx, item.owner_id.to_def_id());
 }
 
 pub(super) fn check_specialization_validity<'tcx>(
@@ -746,7 +743,7 @@ fn check_impl_items_against_trait<'tcx>(
     let trait_def = tcx.trait_def(impl_trait_ref.def_id);
 
     for impl_item in impl_item_refs {
-        let ty_impl_item = tcx.associated_item(impl_item.id.def_id);
+        let ty_impl_item = tcx.associated_item(impl_item.id.owner_id);
         let ty_trait_item = if let Some(trait_item_id) = ty_impl_item.trait_item_def_id {
             tcx.associated_item(trait_item_id)
         } else {
@@ -758,7 +755,7 @@ fn check_impl_items_against_trait<'tcx>(
         match impl_item_full.kind {
             hir::ImplItemKind::Const(..) => {
                 let _ = tcx.compare_assoc_const_impl_item_with_trait_item((
-                    impl_item.id.def_id.def_id,
+                    impl_item.id.owner_id.def_id,
                     ty_impl_item.trait_item_def_id.unwrap(),
                 ));
             }
@@ -1026,7 +1023,7 @@ pub(super) fn check_packed_inner(
     None
 }
 
-pub(super) fn check_transparent<'tcx>(tcx: TyCtxt<'tcx>, sp: Span, adt: ty::AdtDef<'tcx>) {
+pub(super) fn check_transparent<'tcx>(tcx: TyCtxt<'tcx>, adt: ty::AdtDef<'tcx>) {
     if !adt.repr().transparent() {
         return;
     }
@@ -1035,14 +1032,14 @@ pub(super) fn check_transparent<'tcx>(tcx: TyCtxt<'tcx>, sp: Span, adt: ty::AdtD
         feature_err(
             &tcx.sess.parse_sess,
             sym::transparent_unions,
-            sp,
+            tcx.def_span(adt.did()),
             "transparent unions are unstable",
         )
         .emit();
     }
 
     if adt.variants().len() != 1 {
-        bad_variant_count(tcx, adt, sp, adt.did());
+        bad_variant_count(tcx, adt, tcx.def_span(adt.did()), adt.did());
         if adt.variants().is_empty() {
             // Don't bother checking the fields. No variants (and thus no fields) exist.
             return;
@@ -1103,7 +1100,7 @@ pub(super) fn check_transparent<'tcx>(tcx: TyCtxt<'tcx>, sp: Span, adt: ty::AdtD
         .filter_map(|(span, zst, _align1, _non_exhaustive)| if !zst { Some(span) } else { None });
     let non_zst_count = non_zst_fields.clone().count();
     if non_zst_count >= 2 {
-        bad_non_zero_sized_fields(tcx, adt, non_zst_count, non_zst_fields, sp);
+        bad_non_zero_sized_fields(tcx, adt, non_zst_count, non_zst_fields, tcx.def_span(adt.did()));
     }
     let incompatible_zst_fields =
         field_infos.clone().filter(|(_, _, _, opt)| opt.is_some()).count();
@@ -1143,12 +1140,11 @@ pub(super) fn check_transparent<'tcx>(tcx: TyCtxt<'tcx>, sp: Span, adt: ty::AdtD
 }
 
 #[allow(trivial_numeric_casts)]
-fn check_enum<'tcx>(tcx: TyCtxt<'tcx>, vs: &'tcx [hir::Variant<'tcx>], def_id: LocalDefId) {
+fn check_enum<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) {
     let def = tcx.adt_def(def_id);
-    let sp = tcx.def_span(def_id);
     def.destructor(tcx); // force the destructor to be evaluated
 
-    if vs.is_empty() {
+    if def.variants().is_empty() {
         if let Some(attr) = tcx.get_attrs(def_id.to_def_id(), sym::repr).next() {
             struct_span_err!(
                 tcx.sess,
@@ -1156,7 +1152,7 @@ fn check_enum<'tcx>(tcx: TyCtxt<'tcx>, vs: &'tcx [hir::Variant<'tcx>], def_id: L
                 E0084,
                 "unsupported representation for zero-variant enum"
             )
-            .span_label(sp, "zero-variant enum")
+            .span_label(tcx.def_span(def_id), "zero-variant enum")
             .emit();
         }
     }
@@ -1167,88 +1163,96 @@ fn check_enum<'tcx>(tcx: TyCtxt<'tcx>, vs: &'tcx [hir::Variant<'tcx>], def_id: L
             feature_err(
                 &tcx.sess.parse_sess,
                 sym::repr128,
-                sp,
+                tcx.def_span(def_id),
                 "repr with 128-bit type is unstable",
             )
             .emit();
         }
     }
 
-    for v in vs {
-        if let Some(ref e) = v.disr_expr {
-            tcx.ensure().typeck(tcx.hir().local_def_id(e.hir_id));
+    for v in def.variants() {
+        if let ty::VariantDiscr::Explicit(discr_def_id) = v.discr {
+            tcx.ensure().typeck(discr_def_id.expect_local());
         }
     }
 
-    if tcx.adt_def(def_id).repr().int.is_none() && tcx.features().arbitrary_enum_discriminant {
-        let is_unit = |var: &hir::Variant<'_>| matches!(var.data, hir::VariantData::Unit(..));
+    if def.repr().int.is_none() {
+        let is_unit = |var: &ty::VariantDef| matches!(var.ctor_kind, CtorKind::Const);
+        let has_disr = |var: &ty::VariantDef| matches!(var.discr, ty::VariantDiscr::Explicit(_));
 
-        let has_disr = |var: &hir::Variant<'_>| var.disr_expr.is_some();
-        let has_non_units = vs.iter().any(|var| !is_unit(var));
-        let disr_units = vs.iter().any(|var| is_unit(&var) && has_disr(&var));
-        let disr_non_unit = vs.iter().any(|var| !is_unit(&var) && has_disr(&var));
+        let has_non_units = def.variants().iter().any(|var| !is_unit(var));
+        let disr_units = def.variants().iter().any(|var| is_unit(&var) && has_disr(&var));
+        let disr_non_unit = def.variants().iter().any(|var| !is_unit(&var) && has_disr(&var));
 
         if disr_non_unit || (disr_units && has_non_units) {
-            let mut err =
-                struct_span_err!(tcx.sess, sp, E0732, "`#[repr(inttype)]` must be specified");
+            let mut err = struct_span_err!(
+                tcx.sess,
+                tcx.def_span(def_id),
+                E0732,
+                "`#[repr(inttype)]` must be specified"
+            );
             err.emit();
         }
     }
 
-    detect_discriminant_duplicate(tcx, def.discriminants(tcx).collect(), vs, sp);
-
-    check_transparent(tcx, sp, def);
+    detect_discriminant_duplicate(tcx, def);
+    check_transparent(tcx, def);
 }
 
 /// Part of enum check. Given the discriminants of an enum, errors if two or more discriminants are equal
-fn detect_discriminant_duplicate<'tcx>(
-    tcx: TyCtxt<'tcx>,
-    mut discrs: Vec<(VariantIdx, Discr<'tcx>)>,
-    vs: &'tcx [hir::Variant<'tcx>],
-    self_span: Span,
-) {
+fn detect_discriminant_duplicate<'tcx>(tcx: TyCtxt<'tcx>, adt: ty::AdtDef<'tcx>) {
     // Helper closure to reduce duplicate code. This gets called everytime we detect a duplicate.
     // Here `idx` refers to the order of which the discriminant appears, and its index in `vs`
-    let report = |dis: Discr<'tcx>, idx: usize, err: &mut Diagnostic| {
-        let var = &vs[idx]; // HIR for the duplicate discriminant
-        let (span, display_discr) = match var.disr_expr {
-            Some(ref expr) => {
+    let report = |dis: Discr<'tcx>, idx, err: &mut Diagnostic| {
+        let var = adt.variant(idx); // HIR for the duplicate discriminant
+        let (span, display_discr) = match var.discr {
+            ty::VariantDiscr::Explicit(discr_def_id) => {
                 // In the case the discriminant is both a duplicate and overflowed, let the user know
-                if let hir::ExprKind::Lit(lit) = &tcx.hir().body(expr.body).value.kind
+                if let hir::Node::AnonConst(expr) = tcx.hir().get_by_def_id(discr_def_id.expect_local())
+                    && let hir::ExprKind::Lit(lit) = &tcx.hir().body(expr.body).value.kind
                     && let rustc_ast::LitKind::Int(lit_value, _int_kind) = &lit.node
                     && *lit_value != dis.val
                 {
-                    (tcx.hir().span(expr.hir_id), format!("`{dis}` (overflowed from `{lit_value}`)"))
-                // Otherwise, format the value as-is
+                    (tcx.def_span(discr_def_id), format!("`{dis}` (overflowed from `{lit_value}`)"))
                 } else {
-                    (tcx.hir().span(expr.hir_id), format!("`{dis}`"))
+                    // Otherwise, format the value as-is
+                    (tcx.def_span(discr_def_id), format!("`{dis}`"))
                 }
             }
-            None => {
+            // This should not happen.
+            ty::VariantDiscr::Relative(0) => (tcx.def_span(var.def_id), format!("`{dis}`")),
+            ty::VariantDiscr::Relative(distance_to_explicit) => {
                 // At this point we know this discriminant is a duplicate, and was not explicitly
                 // assigned by the user. Here we iterate backwards to fetch the HIR for the last
                 // explicitly assigned discriminant, and letting the user know that this was the
                 // increment startpoint, and how many steps from there leading to the duplicate
-                if let Some((n, hir::Variant { span, ident, .. })) =
-                    vs[..idx].iter().rev().enumerate().find(|v| v.1.disr_expr.is_some())
+                if let Some(explicit_idx) =
+                    idx.as_u32().checked_sub(distance_to_explicit).map(VariantIdx::from_u32)
                 {
-                    let ve_ident = var.ident;
-                    let n = n + 1;
-                    let sp = if n > 1 { "variants" } else { "variant" };
+                    let explicit_variant = adt.variant(explicit_idx);
+                    let ve_ident = var.name;
+                    let ex_ident = explicit_variant.name;
+                    let sp = if distance_to_explicit > 1 { "variants" } else { "variant" };
 
                     err.span_label(
-                        *span,
-                        format!("discriminant for `{ve_ident}` incremented from this startpoint (`{ident}` + {n} {sp} later => `{ve_ident}` = {dis})"),
+                        tcx.def_span(explicit_variant.def_id),
+                        format!(
+                            "discriminant for `{ve_ident}` incremented from this startpoint \
+                            (`{ex_ident}` + {distance_to_explicit} {sp} later \
+                             => `{ve_ident}` = {dis})"
+                        ),
                     );
                 }
 
-                (vs[idx].span, format!("`{dis}`"))
+                (tcx.def_span(var.def_id), format!("`{dis}`"))
             }
         };
 
         err.span_label(span, format!("{display_discr} assigned here"));
     };
 
+    let mut discrs = adt.discriminants(tcx).collect::<Vec<_>>();
+
     // Here we loop through the discriminants, comparing each discriminant to another.
     // When a duplicate is detected, we instantiate an error and point to both
     // initial and duplicate value. The duplicate discriminant is then discarded by swapping
@@ -1257,29 +1261,29 @@ fn detect_discriminant_duplicate<'tcx>(
     // style as we are mutating `discrs` on the fly).
     let mut i = 0;
     while i < discrs.len() {
-        let hir_var_i_idx = discrs[i].0.index();
+        let var_i_idx = discrs[i].0;
         let mut error: Option<DiagnosticBuilder<'_, _>> = None;
 
         let mut o = i + 1;
         while o < discrs.len() {
-            let hir_var_o_idx = discrs[o].0.index();
+            let var_o_idx = discrs[o].0;
 
             if discrs[i].1.val == discrs[o].1.val {
                 let err = error.get_or_insert_with(|| {
                     let mut ret = struct_span_err!(
                         tcx.sess,
-                        self_span,
+                        tcx.def_span(adt.did()),
                         E0081,
                         "discriminant value `{}` assigned more than once",
                         discrs[i].1,
                     );
 
-                    report(discrs[i].1, hir_var_i_idx, &mut ret);
+                    report(discrs[i].1, var_i_idx, &mut ret);
 
                     ret
                 });
 
-                report(discrs[o].1, hir_var_o_idx, err);
+                report(discrs[o].1, var_o_idx, err);
 
                 // Safe to unwrap here, as we wouldn't reach this point if `discrs` was empty
                 discrs[o] = *discrs.last().unwrap();
diff --git a/compiler/rustc_hir_analysis/src/check/compare_method.rs b/compiler/rustc_hir_analysis/src/check/compare_method.rs
index 3469ec4767b7..7c99896b4571 100644
--- a/compiler/rustc_hir_analysis/src/check/compare_method.rs
+++ b/compiler/rustc_hir_analysis/src/check/compare_method.rs
@@ -1,7 +1,7 @@
 use super::potentially_plural_count;
 use crate::errors::LifetimesOrBoundsMismatchOnTrait;
 use hir::def_id::{DefId, LocalDefId};
-use rustc_data_structures::fx::{FxHashMap, FxHashSet};
+use rustc_data_structures::fx::{FxHashMap, FxIndexSet};
 use rustc_errors::{pluralize, struct_span_err, Applicability, DiagnosticId, ErrorGuaranteed};
 use rustc_hir as hir;
 use rustc_hir::def::{DefKind, Res};
@@ -9,14 +9,15 @@ use rustc_hir::intravisit;
 use rustc_hir::{GenericParamKind, ImplItemKind, TraitItemKind};
 use rustc_infer::infer::outlives::env::OutlivesEnvironment;
 use rustc_infer::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKind};
-use rustc_infer::infer::{self, TyCtxtInferExt};
+use rustc_infer::infer::{self, InferCtxt, TyCtxtInferExt};
 use rustc_infer::traits::util;
 use rustc_middle::ty::error::{ExpectedFound, TypeError};
 use rustc_middle::ty::util::ExplicitSelf;
-use rustc_middle::ty::InternalSubsts;
 use rustc_middle::ty::{
-    self, AssocItem, DefIdTree, Ty, TypeFoldable, TypeFolder, TypeSuperFoldable, TypeVisitable,
+    self, AssocItem, DefIdTree, TraitRef, Ty, TypeFoldable, TypeFolder, TypeSuperFoldable,
+    TypeVisitable,
 };
+use rustc_middle::ty::{FnSig, InternalSubsts};
 use rustc_middle::ty::{GenericParamDefKind, ToPredicate, TyCtxt};
 use rustc_span::Span;
 use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt;
@@ -256,7 +257,7 @@ fn compare_predicate_entailment<'tcx>(
     // Compute placeholder form of impl and trait method tys.
     let tcx = infcx.tcx;
 
-    let mut wf_tys = FxHashSet::default();
+    let mut wf_tys = FxIndexSet::default();
 
     let impl_sig = infcx.replace_bound_vars_with_fresh_vars(
         impl_m_span,
@@ -290,10 +291,7 @@ fn compare_predicate_entailment<'tcx>(
     // type would be more appropriate. In other places we have a `Vec<Span>`
     // corresponding to their `Vec<Predicate>`, but we don't have that here.
     // Fixing this would improve the output of test `issue-83765.rs`.
-    let mut result = infcx
-        .at(&cause, param_env)
-        .sup(trait_fty, impl_fty)
-        .map(|infer_ok| ocx.register_infer_ok_obligations(infer_ok));
+    let mut result = ocx.sup(&cause, param_env, trait_fty, impl_fty);
 
     // HACK(RPITIT): #101614. When we are trying to infer the hidden types for
     // RPITITs, we need to equate the output tys instead of just subtyping. If
@@ -301,118 +299,31 @@ fn compare_predicate_entailment<'tcx>(
     // us to infer `_#1t = #'_#2r str`, where `'_#2r` is unconstrained, which gets
     // fixed up to `ReEmpty`, and which is certainly not what we want.
     if trait_fty.has_infer_types() {
-        result = result.and_then(|()| {
-            infcx
-                .at(&cause, param_env)
-                .eq(trait_sig.output(), impl_sig.output())
-                .map(|infer_ok| ocx.register_infer_ok_obligations(infer_ok))
-        });
+        result =
+            result.and_then(|()| ocx.eq(&cause, param_env, trait_sig.output(), impl_sig.output()));
     }
 
     if let Err(terr) = result {
-        debug!("sub_types failed: impl ty {:?}, trait ty {:?}", impl_fty, trait_fty);
+        debug!(?terr, "sub_types failed: impl ty {:?}, trait ty {:?}", impl_fty, trait_fty);
 
-        let (impl_err_span, trait_err_span) =
-            extract_spans_for_error_reporting(&infcx, terr, &cause, impl_m, trait_m);
-
-        cause.span = impl_err_span;
-
-        let mut diag = struct_span_err!(
-            tcx.sess,
-            cause.span(),
-            E0053,
-            "method `{}` has an incompatible type for trait",
-            trait_m.name
-        );
-        match &terr {
-            TypeError::ArgumentMutability(0) | TypeError::ArgumentSorts(_, 0)
-                if trait_m.fn_has_self_parameter =>
-            {
-                let ty = trait_sig.inputs()[0];
-                let sugg = match ExplicitSelf::determine(ty, |_| ty == impl_trait_ref.self_ty()) {
-                    ExplicitSelf::ByValue => "self".to_owned(),
-                    ExplicitSelf::ByReference(_, hir::Mutability::Not) => "&self".to_owned(),
-                    ExplicitSelf::ByReference(_, hir::Mutability::Mut) => "&mut self".to_owned(),
-                    _ => format!("self: {ty}"),
-                };
-
-                // When the `impl` receiver is an arbitrary self type, like `self: Box<Self>`, the
-                // span points only at the type `Box<Self`>, but we want to cover the whole
-                // argument pattern and type.
-                let span = match tcx.hir().expect_impl_item(impl_m.def_id.expect_local()).kind {
-                    ImplItemKind::Fn(ref sig, body) => tcx
-                        .hir()
-                        .body_param_names(body)
-                        .zip(sig.decl.inputs.iter())
-                        .map(|(param, ty)| param.span.to(ty.span))
-                        .next()
-                        .unwrap_or(impl_err_span),
-                    _ => bug!("{:?} is not a method", impl_m),
-                };
-
-                diag.span_suggestion(
-                    span,
-                    "change the self-receiver type to match the trait",
-                    sugg,
-                    Applicability::MachineApplicable,
-                );
-            }
-            TypeError::ArgumentMutability(i) | TypeError::ArgumentSorts(_, i) => {
-                if trait_sig.inputs().len() == *i {
-                    // Suggestion to change output type. We do not suggest in `async` functions
-                    // to avoid complex logic or incorrect output.
-                    match tcx.hir().expect_impl_item(impl_m.def_id.expect_local()).kind {
-                        ImplItemKind::Fn(ref sig, _)
-                            if sig.header.asyncness == hir::IsAsync::NotAsync =>
-                        {
-                            let msg = "change the output type to match the trait";
-                            let ap = Applicability::MachineApplicable;
-                            match sig.decl.output {
-                                hir::FnRetTy::DefaultReturn(sp) => {
-                                    let sugg = format!("-> {} ", trait_sig.output());
-                                    diag.span_suggestion_verbose(sp, msg, sugg, ap);
-                                }
-                                hir::FnRetTy::Return(hir_ty) => {
-                                    let sugg = trait_sig.output();
-                                    diag.span_suggestion(hir_ty.span, msg, sugg, ap);
-                                }
-                            };
-                        }
-                        _ => {}
-                    };
-                } else if let Some(trait_ty) = trait_sig.inputs().get(*i) {
-                    diag.span_suggestion(
-                        impl_err_span,
-                        "change the parameter type to match the trait",
-                        trait_ty,
-                        Applicability::MachineApplicable,
-                    );
-                }
-            }
-            _ => {}
-        }
-
-        infcx.err_ctxt().note_type_err(
-            &mut diag,
-            &cause,
-            trait_err_span.map(|sp| (sp, "type in trait".to_owned())),
-            Some(infer::ValuePairs::Terms(ExpectedFound {
-                expected: trait_fty.into(),
-                found: impl_fty.into(),
-            })),
+        let emitted = report_trait_method_mismatch(
+            tcx,
+            &mut cause,
+            &infcx,
             terr,
-            false,
-            false,
+            (trait_m, trait_fty),
+            (impl_m, impl_fty),
+            &trait_sig,
+            &impl_trait_ref,
         );
-
-        return Err(diag.emit());
+        return Err(emitted);
     }
 
     // Check that all obligations are satisfied by the implementation's
     // version.
     let errors = ocx.select_all_or_error();
     if !errors.is_empty() {
-        let reported = infcx.err_ctxt().report_fulfillment_errors(&errors, None, false);
+        let reported = infcx.err_ctxt().report_fulfillment_errors(&errors, None);
         return Err(reported);
     }
 
@@ -431,6 +342,7 @@ fn compare_predicate_entailment<'tcx>(
     Ok(())
 }
 
+#[instrument(skip(tcx), level = "debug", ret)]
 pub fn collect_trait_impl_trait_tys<'tcx>(
     tcx: TyCtxt<'tcx>,
     def_id: DefId,
@@ -444,7 +356,7 @@ pub fn collect_trait_impl_trait_tys<'tcx>(
 
     let impl_m_hir_id = tcx.hir().local_def_id_to_hir_id(impl_m.def_id.expect_local());
     let return_span = tcx.hir().fn_decl_by_hir_id(impl_m_hir_id).unwrap().output.span();
-    let cause = ObligationCause::new(
+    let mut cause = ObligationCause::new(
         return_span,
         impl_m_hir_id,
         ObligationCauseCode::CompareImplItemObligation {
@@ -486,7 +398,7 @@ pub fn collect_trait_impl_trait_tys<'tcx>(
     let trait_sig = ocx.normalize(norm_cause.clone(), param_env, unnormalized_trait_sig);
     let trait_return_ty = trait_sig.output();
 
-    let wf_tys = FxHashSet::from_iter(
+    let wf_tys = FxIndexSet::from_iter(
         unnormalized_trait_sig.inputs_and_output.iter().chain(trait_sig.inputs_and_output.iter()),
     );
 
@@ -521,23 +433,35 @@ pub fn collect_trait_impl_trait_tys<'tcx>(
         }
     }
 
+    debug!(?trait_sig, ?impl_sig, "equating function signatures");
+
+    let trait_fty = tcx.mk_fn_ptr(ty::Binder::dummy(trait_sig));
+    let impl_fty = tcx.mk_fn_ptr(ty::Binder::dummy(impl_sig));
+
     // Unify the whole function signature. We need to do this to fully infer
     // the lifetimes of the return type, but do this after unifying just the
     // return types, since we want to avoid duplicating errors from
     // `compare_predicate_entailment`.
-    match infcx
-        .at(&cause, param_env)
-        .eq(tcx.mk_fn_ptr(ty::Binder::dummy(trait_sig)), tcx.mk_fn_ptr(ty::Binder::dummy(impl_sig)))
-    {
+    match infcx.at(&cause, param_env).eq(trait_fty, impl_fty) {
         Ok(infer::InferOk { value: (), obligations }) => {
             ocx.register_obligations(obligations);
         }
         Err(terr) => {
-            let guar = tcx.sess.delay_span_bug(
-                return_span,
-                format!("could not unify `{trait_sig}` and `{impl_sig}`: {terr:?}"),
+            // This function gets called during `compare_predicate_entailment` when normalizing a
+            // signature that contains RPITIT. When the method signatures don't match, we have to
+            // emit an error now because `compare_predicate_entailment` will not report the error
+            // when normalization fails.
+            let emitted = report_trait_method_mismatch(
+                tcx,
+                &mut cause,
+                infcx,
+                terr,
+                (trait_m, trait_fty),
+                (impl_m, impl_fty),
+                &trait_sig,
+                &impl_trait_ref,
             );
-            return Err(guar);
+            return Err(emitted);
         }
     }
 
@@ -545,7 +469,7 @@ pub fn collect_trait_impl_trait_tys<'tcx>(
     // RPITs.
     let errors = ocx.select_all_or_error();
     if !errors.is_empty() {
-        let reported = infcx.err_ctxt().report_fulfillment_errors(&errors, None, false);
+        let reported = infcx.err_ctxt().report_fulfillment_errors(&errors, None);
         return Err(reported);
     }
 
@@ -597,9 +521,17 @@ pub fn collect_trait_impl_trait_tys<'tcx>(
                 let num_trait_substs = trait_to_impl_substs.len();
                 let num_impl_substs = tcx.generics_of(impl_m.container_id(tcx)).params.len();
                 let ty = tcx.fold_regions(ty, |region, _| {
-                    let ty::ReFree(_) = region.kind() else { return region; };
-                    let ty::ReEarlyBound(e) = map[&region.into()].expect_region().kind()
-                        else { bug!("expected ReFree to map to ReEarlyBound"); };
+                    let (ty::ReFree(_) | ty::ReEarlyBound(_)) = region.kind() else { return region; };
+                    let Some(ty::ReEarlyBound(e)) = map.get(&region.into()).map(|r| r.expect_region().kind())
+                    else {
+                        tcx
+                            .sess
+                            .delay_span_bug(
+                                return_span,
+                                "expected ReFree to map to ReEarlyBound"
+                            );
+                        return tcx.lifetimes.re_static;
+                    };
                     tcx.mk_region(ty::ReEarlyBound(ty::EarlyBoundRegion {
                         def_id: e.def_id,
                         name: e.name,
@@ -610,11 +542,11 @@ pub fn collect_trait_impl_trait_tys<'tcx>(
                 collected_tys.insert(def_id, ty);
             }
             Err(err) => {
-                tcx.sess.delay_span_bug(
+                let reported = tcx.sess.delay_span_bug(
                     return_span,
                     format!("could not fully resolve: {ty} => {err:?}"),
                 );
-                collected_tys.insert(def_id, tcx.ty_error());
+                collected_tys.insert(def_id, tcx.ty_error_with_guaranteed(reported));
             }
         }
     }
@@ -689,6 +621,112 @@ impl<'tcx> TypeFolder<'tcx> for ImplTraitInTraitCollector<'_, 'tcx> {
     }
 }
 
+fn report_trait_method_mismatch<'tcx>(
+    tcx: TyCtxt<'tcx>,
+    cause: &mut ObligationCause<'tcx>,
+    infcx: &InferCtxt<'tcx>,
+    terr: TypeError<'tcx>,
+    (trait_m, trait_fty): (&AssocItem, Ty<'tcx>),
+    (impl_m, impl_fty): (&AssocItem, Ty<'tcx>),
+    trait_sig: &FnSig<'tcx>,
+    impl_trait_ref: &TraitRef<'tcx>,
+) -> ErrorGuaranteed {
+    let (impl_err_span, trait_err_span) =
+        extract_spans_for_error_reporting(&infcx, terr, &cause, impl_m, trait_m);
+
+    cause.span = impl_err_span;
+
+    let mut diag = struct_span_err!(
+        tcx.sess,
+        cause.span(),
+        E0053,
+        "method `{}` has an incompatible type for trait",
+        trait_m.name
+    );
+    match &terr {
+        TypeError::ArgumentMutability(0) | TypeError::ArgumentSorts(_, 0)
+            if trait_m.fn_has_self_parameter =>
+        {
+            let ty = trait_sig.inputs()[0];
+            let sugg = match ExplicitSelf::determine(ty, |_| ty == impl_trait_ref.self_ty()) {
+                ExplicitSelf::ByValue => "self".to_owned(),
+                ExplicitSelf::ByReference(_, hir::Mutability::Not) => "&self".to_owned(),
+                ExplicitSelf::ByReference(_, hir::Mutability::Mut) => "&mut self".to_owned(),
+                _ => format!("self: {ty}"),
+            };
+
+            // When the `impl` receiver is an arbitrary self type, like `self: Box<Self>`, the
+            // span points only at the type `Box<Self`>, but we want to cover the whole
+            // argument pattern and type.
+            let span = match tcx.hir().expect_impl_item(impl_m.def_id.expect_local()).kind {
+                ImplItemKind::Fn(ref sig, body) => tcx
+                    .hir()
+                    .body_param_names(body)
+                    .zip(sig.decl.inputs.iter())
+                    .map(|(param, ty)| param.span.to(ty.span))
+                    .next()
+                    .unwrap_or(impl_err_span),
+                _ => bug!("{:?} is not a method", impl_m),
+            };
+
+            diag.span_suggestion(
+                span,
+                "change the self-receiver type to match the trait",
+                sugg,
+                Applicability::MachineApplicable,
+            );
+        }
+        TypeError::ArgumentMutability(i) | TypeError::ArgumentSorts(_, i) => {
+            if trait_sig.inputs().len() == *i {
+                // Suggestion to change output type. We do not suggest in `async` functions
+                // to avoid complex logic or incorrect output.
+                match tcx.hir().expect_impl_item(impl_m.def_id.expect_local()).kind {
+                    ImplItemKind::Fn(ref sig, _)
+                        if sig.header.asyncness == hir::IsAsync::NotAsync =>
+                    {
+                        let msg = "change the output type to match the trait";
+                        let ap = Applicability::MachineApplicable;
+                        match sig.decl.output {
+                            hir::FnRetTy::DefaultReturn(sp) => {
+                                let sugg = format!("-> {} ", trait_sig.output());
+                                diag.span_suggestion_verbose(sp, msg, sugg, ap);
+                            }
+                            hir::FnRetTy::Return(hir_ty) => {
+                                let sugg = trait_sig.output();
+                                diag.span_suggestion(hir_ty.span, msg, sugg, ap);
+                            }
+                        };
+                    }
+                    _ => {}
+                };
+            } else if let Some(trait_ty) = trait_sig.inputs().get(*i) {
+                diag.span_suggestion(
+                    impl_err_span,
+                    "change the parameter type to match the trait",
+                    trait_ty,
+                    Applicability::MachineApplicable,
+                );
+            }
+        }
+        _ => {}
+    }
+
+    infcx.err_ctxt().note_type_err(
+        &mut diag,
+        &cause,
+        trait_err_span.map(|sp| (sp, "type in trait".to_owned())),
+        Some(infer::ValuePairs::Terms(ExpectedFound {
+            expected: trait_fty.into(),
+            found: impl_fty.into(),
+        })),
+        terr,
+        false,
+        false,
+    );
+
+    return diag.emit();
+}
+
 fn check_region_bounds_on_impl_item<'tcx>(
     tcx: TyCtxt<'tcx>,
     impl_m: &ty::AssocItem,
@@ -1381,10 +1419,7 @@ pub(crate) fn raw_compare_const_impl<'tcx>(
 
     debug!("compare_const_impl: trait_ty={:?}", trait_ty);
 
-    let err = infcx
-        .at(&cause, param_env)
-        .sup(trait_ty, impl_ty)
-        .map(|ok| ocx.register_infer_ok_obligations(ok));
+    let err = ocx.sup(&cause, param_env, trait_ty, impl_ty);
 
     if let Err(terr) = err {
         debug!(
@@ -1433,7 +1468,7 @@ pub(crate) fn raw_compare_const_impl<'tcx>(
     // version.
     let errors = ocx.select_all_or_error();
     if !errors.is_empty() {
-        return Err(infcx.err_ctxt().report_fulfillment_errors(&errors, None, false));
+        return Err(infcx.err_ctxt().report_fulfillment_errors(&errors, None));
     }
 
     // FIXME return `ErrorReported` if region obligations error?
@@ -1551,7 +1586,7 @@ fn compare_type_predicate_entailment<'tcx>(
     // version.
     let errors = ocx.select_all_or_error();
     if !errors.is_empty() {
-        let reported = infcx.err_ctxt().report_fulfillment_errors(&errors, None, false);
+        let reported = infcx.err_ctxt().report_fulfillment_errors(&errors, None);
         return Err(reported);
     }
 
@@ -1657,13 +1692,10 @@ pub fn check_type_bounds<'tcx>(
         GenericParamDefKind::Const { .. } => {
             let bound_var = ty::BoundVariableKind::Const;
             bound_vars.push(bound_var);
-            tcx.mk_const(ty::ConstS {
-                ty: tcx.type_of(param.def_id),
-                kind: ty::ConstKind::Bound(
-                    ty::INNERMOST,
-                    ty::BoundVar::from_usize(bound_vars.len() - 1),
-                ),
-            })
+            tcx.mk_const(
+                ty::ConstKind::Bound(ty::INNERMOST, ty::BoundVar::from_usize(bound_vars.len() - 1)),
+                tcx.type_of(param.def_id),
+            )
             .into()
         }
     });
@@ -1774,7 +1806,7 @@ pub fn check_type_bounds<'tcx>(
     // version.
     let errors = ocx.select_all_or_error();
     if !errors.is_empty() {
-        let reported = infcx.err_ctxt().report_fulfillment_errors(&errors, None, false);
+        let reported = infcx.err_ctxt().report_fulfillment_errors(&errors, None);
         return Err(reported);
     }
 
diff --git a/compiler/rustc_hir_analysis/src/check/intrinsic.rs b/compiler/rustc_hir_analysis/src/check/intrinsic.rs
index 8be1cf04f8b6..69e54b41d4c0 100644
--- a/compiler/rustc_hir_analysis/src/check/intrinsic.rs
+++ b/compiler/rustc_hir_analysis/src/check/intrinsic.rs
@@ -26,7 +26,7 @@ fn equate_intrinsic_type<'tcx>(
 ) {
     let (own_counts, span) = match &it.kind {
         hir::ForeignItemKind::Fn(.., generics) => {
-            let own_counts = tcx.generics_of(it.def_id.to_def_id()).own_counts();
+            let own_counts = tcx.generics_of(it.owner_id.to_def_id()).own_counts();
             (own_counts, generics.span)
         }
         _ => {
@@ -57,7 +57,7 @@ fn equate_intrinsic_type<'tcx>(
     {
         let fty = tcx.mk_fn_ptr(sig);
         let cause = ObligationCause::new(it.span, it.hir_id(), ObligationCauseCode::IntrinsicType);
-        require_same_types(tcx, &cause, tcx.mk_fn_ptr(tcx.fn_sig(it.def_id)), fty);
+        require_same_types(tcx, &cause, tcx.mk_fn_ptr(tcx.fn_sig(it.owner_id)), fty);
     }
 }
 
@@ -129,20 +129,23 @@ pub fn intrinsic_operation_unsafety(tcx: TyCtxt<'_>, intrinsic_id: DefId) -> hir
 /// and in `library/core/src/intrinsics.rs`.
 pub fn check_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) {
     let param = |n| tcx.mk_ty_param(n, Symbol::intern(&format!("P{}", n)));
-    let intrinsic_id = it.def_id.to_def_id();
+    let intrinsic_id = it.owner_id.to_def_id();
     let intrinsic_name = tcx.item_name(intrinsic_id);
     let name_str = intrinsic_name.as_str();
 
     let bound_vars = tcx.mk_bound_variable_kinds(
-        [ty::BoundVariableKind::Region(ty::BrAnon(0)), ty::BoundVariableKind::Region(ty::BrEnv)]
-            .iter()
-            .copied(),
+        [
+            ty::BoundVariableKind::Region(ty::BrAnon(0, None)),
+            ty::BoundVariableKind::Region(ty::BrEnv),
+        ]
+        .iter()
+        .copied(),
     );
     let mk_va_list_ty = |mutbl| {
         tcx.lang_items().va_list().map(|did| {
             let region = tcx.mk_region(ty::ReLateBound(
                 ty::INNERMOST,
-                ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0) },
+                ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0, None) },
             ));
             let env_region = tcx.mk_region(ty::ReLateBound(
                 ty::INNERMOST,
@@ -364,7 +367,8 @@ pub fn check_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) {
                 );
                 let discriminant_def_id = assoc_items[0];
 
-                let br = ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0) };
+                let br =
+                    ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0, None) };
                 (
                     1,
                     vec![
@@ -418,7 +422,8 @@ pub fn check_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) {
             sym::nontemporal_store => (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], tcx.mk_unit()),
 
             sym::raw_eq => {
-                let br = ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0) };
+                let br =
+                    ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind: ty::BrAnon(0, None) };
                 let param_ty =
                     tcx.mk_imm_ref(tcx.mk_region(ty::ReLateBound(ty::INNERMOST, br)), param(0));
                 (1, vec![param_ty; 2], tcx.types.bool)
diff --git a/compiler/rustc_hir_analysis/src/check/intrinsicck.rs b/compiler/rustc_hir_analysis/src/check/intrinsicck.rs
index a026f8033c8c..17c4d0d482f2 100644
--- a/compiler/rustc_hir_analysis/src/check/intrinsicck.rs
+++ b/compiler/rustc_hir_analysis/src/check/intrinsicck.rs
@@ -33,7 +33,7 @@ impl<'a, 'tcx> InlineAsmCtxt<'a, 'tcx> {
     fn is_thin_ptr_ty(&self, ty: Ty<'tcx>) -> bool {
         // Type still may have region variables, but `Sized` does not depend
         // on those, so just erase them before querying.
-        if ty.is_sized(self.tcx.at(DUMMY_SP), self.param_env) {
+        if ty.is_sized(self.tcx, self.param_env) {
             return true;
         }
         if let ty::Foreign(..) = ty.kind() {
@@ -128,7 +128,7 @@ impl<'a, 'tcx> InlineAsmCtxt<'a, 'tcx> {
 
         // Check that the type implements Copy. The only case where this can
         // possibly fail is for SIMD types which don't #[derive(Copy)].
-        if !ty.is_copy_modulo_regions(self.tcx.at(expr.span), self.param_env) {
+        if !ty.is_copy_modulo_regions(self.tcx, self.param_env) {
             let msg = "arguments for inline assembly must be copyable";
             let mut err = self.tcx.sess.struct_span_err(expr.span, msg);
             err.note(&format!("`{ty}` does not implement the Copy trait"));
diff --git a/compiler/rustc_hir_analysis/src/check/wfcheck.rs b/compiler/rustc_hir_analysis/src/check/wfcheck.rs
index 33ed3b96aa81..837ff0bdf3e3 100644
--- a/compiler/rustc_hir_analysis/src/check/wfcheck.rs
+++ b/compiler/rustc_hir_analysis/src/check/wfcheck.rs
@@ -1,7 +1,7 @@
 use crate::constrained_generic_params::{identify_constrained_generic_params, Parameter};
 use hir::def::DefKind;
 use rustc_ast as ast;
-use rustc_data_structures::fx::{FxHashMap, FxHashSet};
+use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexSet};
 use rustc_errors::{pluralize, struct_span_err, Applicability, DiagnosticBuilder, ErrorGuaranteed};
 use rustc_hir as hir;
 use rustc_hir::def_id::{DefId, LocalDefId};
@@ -21,6 +21,7 @@ use rustc_middle::ty::{GenericArgKind, InternalSubsts};
 use rustc_session::parse::feature_err;
 use rustc_span::symbol::{sym, Ident, Symbol};
 use rustc_span::{Span, DUMMY_SP};
+use rustc_target::spec::abi::Abi;
 use rustc_trait_selection::autoderef::Autoderef;
 use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt;
 use rustc_trait_selection::traits::outlives_bounds::InferCtxtExt as _;
@@ -104,7 +105,7 @@ pub(super) fn enter_wf_checking_ctxt<'tcx, F>(
     f(&mut wfcx);
     let errors = wfcx.select_all_or_error();
     if !errors.is_empty() {
-        infcx.err_ctxt().report_fulfillment_errors(&errors, None, false);
+        infcx.err_ctxt().report_fulfillment_errors(&errors, None);
         return;
     }
 
@@ -116,7 +117,7 @@ pub(super) fn enter_wf_checking_ctxt<'tcx, F>(
 }
 
 fn check_well_formed(tcx: TyCtxt<'_>, def_id: hir::OwnerId) {
-    let node = tcx.hir().expect_owner(def_id);
+    let node = tcx.hir().owner(def_id);
     match node {
         hir::OwnerNode::Crate(_) => {}
         hir::OwnerNode::Item(item) => check_item(tcx, item),
@@ -147,10 +148,10 @@ fn check_well_formed(tcx: TyCtxt<'_>, def_id: hir::OwnerId) {
 /// the types first.
 #[instrument(skip(tcx), level = "debug")]
 fn check_item<'tcx>(tcx: TyCtxt<'tcx>, item: &'tcx hir::Item<'tcx>) {
-    let def_id = item.def_id.def_id;
+    let def_id = item.owner_id.def_id;
 
     debug!(
-        ?item.def_id,
+        ?item.owner_id,
         item.name = ? tcx.def_path_str(def_id.to_def_id())
     );
 
@@ -218,19 +219,16 @@ fn check_item<'tcx>(tcx: TyCtxt<'tcx>, item: &'tcx hir::Item<'tcx>) {
         hir::ItemKind::Const(ty, ..) => {
             check_item_type(tcx, def_id, ty.span, false);
         }
-        hir::ItemKind::Struct(ref struct_def, ref ast_generics) => {
-            check_type_defn(tcx, item, false, |wfcx| vec![wfcx.non_enum_variant(struct_def)]);
-
+        hir::ItemKind::Struct(_, ref ast_generics) => {
+            check_type_defn(tcx, item, false);
             check_variances_for_type_defn(tcx, item, ast_generics);
         }
-        hir::ItemKind::Union(ref struct_def, ref ast_generics) => {
-            check_type_defn(tcx, item, true, |wfcx| vec![wfcx.non_enum_variant(struct_def)]);
-
+        hir::ItemKind::Union(_, ref ast_generics) => {
+            check_type_defn(tcx, item, true);
             check_variances_for_type_defn(tcx, item, ast_generics);
         }
-        hir::ItemKind::Enum(ref enum_def, ref ast_generics) => {
-            check_type_defn(tcx, item, true, |wfcx| wfcx.enum_variants(enum_def));
-
+        hir::ItemKind::Enum(_, ref ast_generics) => {
+            check_type_defn(tcx, item, true);
             check_variances_for_type_defn(tcx, item, ast_generics);
         }
         hir::ItemKind::Trait(..) => {
@@ -246,10 +244,10 @@ fn check_item<'tcx>(tcx: TyCtxt<'tcx>, item: &'tcx hir::Item<'tcx>) {
 }
 
 fn check_foreign_item(tcx: TyCtxt<'_>, item: &hir::ForeignItem<'_>) {
-    let def_id = item.def_id.def_id;
+    let def_id = item.owner_id.def_id;
 
     debug!(
-        ?item.def_id,
+        ?item.owner_id,
         item.name = ? tcx.def_path_str(def_id.to_def_id())
     );
 
@@ -263,7 +261,7 @@ fn check_foreign_item(tcx: TyCtxt<'_>, item: &hir::ForeignItem<'_>) {
 }
 
 fn check_trait_item(tcx: TyCtxt<'_>, trait_item: &hir::TraitItem<'_>) {
-    let def_id = trait_item.def_id.def_id;
+    let def_id = trait_item.owner_id.def_id;
 
     let (method_sig, span) = match trait_item.kind {
         hir::TraitItemKind::Fn(ref sig, _) => (Some(sig), trait_item.span),
@@ -275,7 +273,7 @@ fn check_trait_item(tcx: TyCtxt<'_>, trait_item: &hir::TraitItem<'_>) {
 
     let encl_trait_def_id = tcx.local_parent(def_id);
     let encl_trait = tcx.hir().expect_item(encl_trait_def_id);
-    let encl_trait_def_id = encl_trait.def_id.to_def_id();
+    let encl_trait_def_id = encl_trait.owner_id.to_def_id();
     let fn_lang_item_name = if Some(encl_trait_def_id) == tcx.lang_items().fn_trait() {
         Some("fn")
     } else if Some(encl_trait_def_id) == tcx.lang_items().fn_mut_trait() {
@@ -348,7 +346,7 @@ fn check_gat_where_clauses(tcx: TyCtxt<'_>, associated_items: &[hir::TraitItemRe
     loop {
         let mut should_continue = false;
         for gat_item in associated_items {
-            let gat_def_id = gat_item.id.def_id;
+            let gat_def_id = gat_item.id.owner_id;
             let gat_item = tcx.associated_item(gat_def_id);
             // If this item is not an assoc ty, or has no substs, then it's not a GAT
             if gat_item.kind != ty::AssocKind::Type {
@@ -365,7 +363,7 @@ fn check_gat_where_clauses(tcx: TyCtxt<'_>, associated_items: &[hir::TraitItemRe
             // constrains the GAT with individually.
             let mut new_required_bounds: Option<FxHashSet<ty::Predicate<'_>>> = None;
             for item in associated_items {
-                let item_def_id = item.id.def_id;
+                let item_def_id = item.id.owner_id;
                 // Skip our own GAT, since it does not constrain itself at all.
                 if item_def_id == gat_def_id {
                     continue;
@@ -414,7 +412,7 @@ fn check_gat_where_clauses(tcx: TyCtxt<'_>, associated_items: &[hir::TraitItemRe
                                 .iter()
                                 .copied()
                                 .collect::<Vec<_>>(),
-                            &FxHashSet::default(),
+                            &FxIndexSet::default(),
                             gat_def_id.def_id,
                             gat_generics,
                         )
@@ -464,10 +462,10 @@ fn check_gat_where_clauses(tcx: TyCtxt<'_>, associated_items: &[hir::TraitItemRe
             .into_iter()
             .filter(|clause| match clause.kind().skip_binder() {
                 ty::PredicateKind::RegionOutlives(ty::OutlivesPredicate(a, b)) => {
-                    !region_known_to_outlive(tcx, gat_hir, param_env, &FxHashSet::default(), a, b)
+                    !region_known_to_outlive(tcx, gat_hir, param_env, &FxIndexSet::default(), a, b)
                 }
                 ty::PredicateKind::TypeOutlives(ty::OutlivesPredicate(a, b)) => {
-                    !ty_known_to_outlive(tcx, gat_hir, param_env, &FxHashSet::default(), a, b)
+                    !ty_known_to_outlive(tcx, gat_hir, param_env, &FxIndexSet::default(), a, b)
                 }
                 _ => bug!("Unexpected PredicateKind"),
             })
@@ -549,7 +547,7 @@ fn gather_gat_bounds<'tcx, T: TypeFoldable<'tcx>>(
     param_env: ty::ParamEnv<'tcx>,
     item_hir: hir::HirId,
     to_check: T,
-    wf_tys: &FxHashSet<Ty<'tcx>>,
+    wf_tys: &FxIndexSet<Ty<'tcx>>,
     gat_def_id: LocalDefId,
     gat_generics: &'tcx ty::Generics,
 ) -> Option<FxHashSet<ty::Predicate<'tcx>>> {
@@ -656,7 +654,7 @@ fn ty_known_to_outlive<'tcx>(
     tcx: TyCtxt<'tcx>,
     id: hir::HirId,
     param_env: ty::ParamEnv<'tcx>,
-    wf_tys: &FxHashSet<Ty<'tcx>>,
+    wf_tys: &FxIndexSet<Ty<'tcx>>,
     ty: Ty<'tcx>,
     region: ty::Region<'tcx>,
 ) -> bool {
@@ -673,7 +671,7 @@ fn region_known_to_outlive<'tcx>(
     tcx: TyCtxt<'tcx>,
     id: hir::HirId,
     param_env: ty::ParamEnv<'tcx>,
-    wf_tys: &FxHashSet<Ty<'tcx>>,
+    wf_tys: &FxIndexSet<Ty<'tcx>>,
     region_a: ty::Region<'tcx>,
     region_b: ty::Region<'tcx>,
 ) -> bool {
@@ -697,7 +695,7 @@ fn resolve_regions_with_wf_tys<'tcx>(
     tcx: TyCtxt<'tcx>,
     id: hir::HirId,
     param_env: ty::ParamEnv<'tcx>,
-    wf_tys: &FxHashSet<Ty<'tcx>>,
+    wf_tys: &FxIndexSet<Ty<'tcx>>,
     add_constraints: impl for<'a> FnOnce(&'a InferCtxt<'tcx>, &'a RegionBoundPairs<'tcx>),
 ) -> bool {
     // Unfortunately, we have to use a new `InferCtxt` each call, because
@@ -713,6 +711,10 @@ fn resolve_regions_with_wf_tys<'tcx>(
 
     add_constraints(&infcx, region_bound_pairs);
 
+    infcx.process_registered_region_obligations(
+        outlives_environment.region_bound_pairs(),
+        param_env,
+    );
     let errors = infcx.resolve_regions(&outlives_environment);
 
     debug!(?errors, "errors");
@@ -786,7 +788,7 @@ fn check_object_unsafe_self_trait_by_name(tcx: TyCtxt<'_>, item: &hir::TraitItem
     let (trait_name, trait_def_id) =
         match tcx.hir().get_by_def_id(tcx.hir().get_parent_item(item.hir_id()).def_id) {
             hir::Node::Item(item) => match item.kind {
-                hir::ItemKind::Trait(..) => (item.ident, item.def_id),
+                hir::ItemKind::Trait(..) => (item.ident, item.owner_id),
                 _ => return,
             },
             _ => return,
@@ -841,7 +843,7 @@ fn check_impl_item(tcx: TyCtxt<'_>, impl_item: &hir::ImplItem<'_>) {
         _ => (None, impl_item.span),
     };
 
-    check_associated_item(tcx, impl_item.def_id.def_id, span, method_sig);
+    check_associated_item(tcx, impl_item.owner_id.def_id, span, method_sig);
 }
 
 fn check_param_wf(tcx: TyCtxt<'_>, param: &hir::GenericParam<'_>) {
@@ -1033,27 +1035,25 @@ fn item_adt_kind(kind: &ItemKind<'_>) -> Option<AdtKind> {
 }
 
 /// In a type definition, we check that to ensure that the types of the fields are well-formed.
-fn check_type_defn<'tcx, F>(
-    tcx: TyCtxt<'tcx>,
-    item: &hir::Item<'tcx>,
-    all_sized: bool,
-    mut lookup_fields: F,
-) where
-    F: FnMut(&WfCheckingCtxt<'_, 'tcx>) -> Vec<AdtVariant<'tcx>>,
-{
-    let _ = tcx.representability(item.def_id.def_id);
+fn check_type_defn<'tcx>(tcx: TyCtxt<'tcx>, item: &hir::Item<'tcx>, all_sized: bool) {
+    let _ = tcx.representability(item.owner_id.def_id);
+    let adt_def = tcx.adt_def(item.owner_id);
 
-    enter_wf_checking_ctxt(tcx, item.span, item.def_id.def_id, |wfcx| {
-        let variants = lookup_fields(wfcx);
-        let packed = tcx.adt_def(item.def_id).repr().packed();
+    enter_wf_checking_ctxt(tcx, item.span, item.owner_id.def_id, |wfcx| {
+        let variants = adt_def.variants();
+        let packed = adt_def.repr().packed();
 
-        for variant in &variants {
+        for variant in variants.iter() {
             // All field types must be well-formed.
             for field in &variant.fields {
+                let field_id = field.did.expect_local();
+                let hir::Node::Field(hir::FieldDef { ty: hir_ty, .. }) = tcx.hir().get_by_def_id(field_id)
+                else { bug!() };
+                let ty = wfcx.normalize(hir_ty.span, None, tcx.type_of(field.did));
                 wfcx.register_wf_obligation(
-                    field.span,
-                    Some(WellFormedLoc::Ty(field.def_id)),
-                    field.ty.into(),
+                    hir_ty.span,
+                    Some(WellFormedLoc::Ty(field_id)),
+                    ty.into(),
                 )
             }
 
@@ -1061,7 +1061,7 @@ fn check_type_defn<'tcx, F>(
             // intermediate types must be sized.
             let needs_drop_copy = || {
                 packed && {
-                    let ty = variant.fields.last().unwrap().ty;
+                    let ty = tcx.type_of(variant.fields.last().unwrap().did);
                     let ty = tcx.erase_regions(ty);
                     if ty.needs_infer() {
                         tcx.sess
@@ -1069,7 +1069,7 @@ fn check_type_defn<'tcx, F>(
                         // Just treat unresolved type expression as if it needs drop.
                         true
                     } else {
-                        ty.needs_drop(tcx, tcx.param_env(item.def_id))
+                        ty.needs_drop(tcx, tcx.param_env(item.owner_id))
                     }
                 }
             };
@@ -1080,27 +1080,31 @@ fn check_type_defn<'tcx, F>(
                 variant.fields[..variant.fields.len() - unsized_len].iter().enumerate()
             {
                 let last = idx == variant.fields.len() - 1;
+                let field_id = field.did.expect_local();
+                let hir::Node::Field(hir::FieldDef { ty: hir_ty, .. }) = tcx.hir().get_by_def_id(field_id)
+                else { bug!() };
+                let ty = wfcx.normalize(hir_ty.span, None, tcx.type_of(field.did));
                 wfcx.register_bound(
                     traits::ObligationCause::new(
-                        field.span,
+                        hir_ty.span,
                         wfcx.body_id,
                         traits::FieldSized {
                             adt_kind: match item_adt_kind(&item.kind) {
                                 Some(i) => i,
                                 None => bug!(),
                             },
-                            span: field.span,
+                            span: hir_ty.span,
                             last,
                         },
                     ),
                     wfcx.param_env,
-                    field.ty,
+                    ty,
                     tcx.require_lang_item(LangItem::Sized, None),
                 );
             }
 
             // Explicit `enum` discriminant values must const-evaluate successfully.
-            if let Some(discr_def_id) = variant.explicit_discr {
+            if let ty::VariantDiscr::Explicit(discr_def_id) = variant.discr {
                 let cause = traits::ObligationCause::new(
                     tcx.def_span(discr_def_id),
                     wfcx.body_id,
@@ -1110,22 +1114,22 @@ fn check_type_defn<'tcx, F>(
                     cause,
                     wfcx.param_env,
                     ty::Binder::dummy(ty::PredicateKind::ConstEvaluatable(
-                        ty::Const::from_anon_const(tcx, discr_def_id),
+                        ty::Const::from_anon_const(tcx, discr_def_id.expect_local()),
                     ))
                     .to_predicate(tcx),
                 ));
             }
         }
 
-        check_where_clauses(wfcx, item.span, item.def_id.def_id);
+        check_where_clauses(wfcx, item.span, item.owner_id.def_id);
     });
 }
 
 #[instrument(skip(tcx, item))]
 fn check_trait(tcx: TyCtxt<'_>, item: &hir::Item<'_>) {
-    debug!(?item.def_id);
+    debug!(?item.owner_id);
 
-    let def_id = item.def_id.def_id;
+    let def_id = item.owner_id.def_id;
     let trait_def = tcx.trait_def(def_id);
     if trait_def.is_marker
         || matches!(trait_def.specialization_kind, TraitSpecializationKind::Marker)
@@ -1236,13 +1240,13 @@ fn check_impl<'tcx>(
     ast_trait_ref: &Option<hir::TraitRef<'_>>,
     constness: hir::Constness,
 ) {
-    enter_wf_checking_ctxt(tcx, item.span, item.def_id.def_id, |wfcx| {
+    enter_wf_checking_ctxt(tcx, item.span, item.owner_id.def_id, |wfcx| {
         match *ast_trait_ref {
             Some(ref ast_trait_ref) => {
                 // `#[rustc_reservation_impl]` impls are not real impls and
                 // therefore don't need to be WF (the trait's `Self: Trait` predicate
                 // won't hold).
-                let trait_ref = tcx.impl_trait_ref(item.def_id).unwrap();
+                let trait_ref = tcx.impl_trait_ref(item.owner_id).unwrap();
                 let trait_ref = wfcx.normalize(ast_trait_ref.path.span, None, trait_ref);
                 let trait_pred = ty::TraitPredicate {
                     trait_ref,
@@ -1264,7 +1268,7 @@ fn check_impl<'tcx>(
                 wfcx.register_obligations(obligations);
             }
             None => {
-                let self_ty = tcx.type_of(item.def_id);
+                let self_ty = tcx.type_of(item.owner_id);
                 let self_ty = wfcx.normalize(
                     item.span,
                     Some(WellFormedLoc::Ty(item.hir_id().expect_owner().def_id)),
@@ -1278,7 +1282,7 @@ fn check_impl<'tcx>(
             }
         }
 
-        check_where_clauses(wfcx, item.span, item.def_id.def_id);
+        check_where_clauses(wfcx, item.span, item.owner_id.def_id);
     });
 }
 
@@ -1539,6 +1543,33 @@ fn check_fn_or_method<'tcx>(
         sig.output(),
         hir_decl.output.span(),
     );
+
+    if sig.abi == Abi::RustCall {
+        let span = tcx.def_span(def_id);
+        let has_implicit_self = hir_decl.implicit_self != hir::ImplicitSelfKind::None;
+        let mut inputs = sig.inputs().iter().skip(if has_implicit_self { 1 } else { 0 });
+        // Check that the argument is a tuple
+        if let Some(ty) = inputs.next() {
+            wfcx.register_bound(
+                ObligationCause::new(span, wfcx.body_id, ObligationCauseCode::RustCall),
+                wfcx.param_env,
+                *ty,
+                tcx.require_lang_item(hir::LangItem::Tuple, Some(span)),
+            );
+        } else {
+            tcx.sess.span_err(
+                hir_decl.inputs.last().map_or(span, |input| input.span),
+                "functions with the \"rust-call\" ABI must take a single non-self tuple argument",
+            );
+        }
+        // No more inputs other than the `self` type and the tuple type
+        if inputs.next().is_some() {
+            tcx.sess.span_err(
+                hir_decl.inputs.last().map_or(span, |input| input.span),
+                "functions with the \"rust-call\" ABI must take a single non-self tuple argument",
+            );
+        }
+    }
 }
 
 /// Basically `check_associated_type_bounds`, but separated for now and should be
@@ -1671,14 +1702,13 @@ fn receiver_is_valid<'tcx>(
 
     // `self: Self` is always valid.
     if can_eq_self(receiver_ty) {
-        if let Err(err) = wfcx.equate_types(&cause, wfcx.param_env, self_ty, receiver_ty) {
+        if let Err(err) = wfcx.eq(&cause, wfcx.param_env, self_ty, receiver_ty) {
             infcx.err_ctxt().report_mismatched_types(&cause, self_ty, receiver_ty, err).emit();
         }
         return true;
     }
 
-    let mut autoderef =
-        Autoderef::new(infcx, wfcx.param_env, wfcx.body_id, span, receiver_ty, span);
+    let mut autoderef = Autoderef::new(infcx, wfcx.param_env, wfcx.body_id, span, receiver_ty);
 
     // The `arbitrary_self_types` feature allows raw pointer receivers like `self: *const Self`.
     if arbitrary_self_types_enabled {
@@ -1701,9 +1731,7 @@ fn receiver_is_valid<'tcx>(
             if can_eq_self(potential_self_ty) {
                 wfcx.register_obligations(autoderef.into_obligations());
 
-                if let Err(err) =
-                    wfcx.equate_types(&cause, wfcx.param_env, self_ty, potential_self_ty)
-                {
+                if let Err(err) = wfcx.eq(&cause, wfcx.param_env, self_ty, potential_self_ty) {
                     infcx
                         .err_ctxt()
                         .report_mismatched_types(&cause, self_ty, potential_self_ty, err)
@@ -1774,14 +1802,14 @@ fn check_variances_for_type_defn<'tcx>(
     item: &hir::Item<'tcx>,
     hir_generics: &hir::Generics<'_>,
 ) {
-    let ty = tcx.type_of(item.def_id);
+    let ty = tcx.type_of(item.owner_id);
     if tcx.has_error_field(ty) {
         return;
     }
 
-    let ty_predicates = tcx.predicates_of(item.def_id);
+    let ty_predicates = tcx.predicates_of(item.owner_id);
     assert_eq!(ty_predicates.parent, None);
-    let variances = tcx.variances_of(item.def_id);
+    let variances = tcx.variances_of(item.owner_id);
 
     let mut constrained_parameters: FxHashSet<_> = variances
         .iter()
@@ -1794,7 +1822,7 @@ fn check_variances_for_type_defn<'tcx>(
 
     // Lazily calculated because it is only needed in case of an error.
     let explicitly_bounded_params = LazyCell::new(|| {
-        let icx = crate::collect::ItemCtxt::new(tcx, item.def_id.to_def_id());
+        let icx = crate::collect::ItemCtxt::new(tcx, item.owner_id.to_def_id());
         hir_generics
             .predicates
             .iter()
@@ -1915,60 +1943,10 @@ impl<'tcx> WfCheckingCtxt<'_, 'tcx> {
 
 fn check_mod_type_wf(tcx: TyCtxt<'_>, module: LocalDefId) {
     let items = tcx.hir_module_items(module);
-    items.par_items(|item| tcx.ensure().check_well_formed(item.def_id));
-    items.par_impl_items(|item| tcx.ensure().check_well_formed(item.def_id));
-    items.par_trait_items(|item| tcx.ensure().check_well_formed(item.def_id));
-    items.par_foreign_items(|item| tcx.ensure().check_well_formed(item.def_id));
-}
-
-///////////////////////////////////////////////////////////////////////////
-// ADT
-
-// FIXME(eddyb) replace this with getting fields/discriminants through `ty::AdtDef`.
-struct AdtVariant<'tcx> {
-    /// Types of fields in the variant, that must be well-formed.
-    fields: Vec<AdtField<'tcx>>,
-
-    /// Explicit discriminant of this variant (e.g. `A = 123`),
-    /// that must evaluate to a constant value.
-    explicit_discr: Option<LocalDefId>,
-}
-
-struct AdtField<'tcx> {
-    ty: Ty<'tcx>,
-    def_id: LocalDefId,
-    span: Span,
-}
-
-impl<'a, 'tcx> WfCheckingCtxt<'a, 'tcx> {
-    // FIXME(eddyb) replace this with getting fields through `ty::AdtDef`.
-    fn non_enum_variant(&self, struct_def: &hir::VariantData<'_>) -> AdtVariant<'tcx> {
-        let fields = struct_def
-            .fields()
-            .iter()
-            .map(|field| {
-                let def_id = self.tcx().hir().local_def_id(field.hir_id);
-                let field_ty = self.tcx().type_of(def_id);
-                let field_ty = self.normalize(field.ty.span, None, field_ty);
-                debug!("non_enum_variant: type of field {:?} is {:?}", field, field_ty);
-                AdtField { ty: field_ty, span: field.ty.span, def_id }
-            })
-            .collect();
-        AdtVariant { fields, explicit_discr: None }
-    }
-
-    fn enum_variants(&self, enum_def: &hir::EnumDef<'_>) -> Vec<AdtVariant<'tcx>> {
-        enum_def
-            .variants
-            .iter()
-            .map(|variant| AdtVariant {
-                fields: self.non_enum_variant(&variant.data).fields,
-                explicit_discr: variant
-                    .disr_expr
-                    .map(|explicit_discr| self.tcx().hir().local_def_id(explicit_discr.hir_id)),
-            })
-            .collect()
-    }
+    items.par_items(|item| tcx.ensure().check_well_formed(item.owner_id));
+    items.par_impl_items(|item| tcx.ensure().check_well_formed(item.owner_id));
+    items.par_trait_items(|item| tcx.ensure().check_well_formed(item.owner_id));
+    items.par_foreign_items(|item| tcx.ensure().check_well_formed(item.owner_id));
 }
 
 fn error_392(
diff --git a/compiler/rustc_hir_analysis/src/check_unused.rs b/compiler/rustc_hir_analysis/src/check_unused.rs
index 922833f85806..d0c31733481b 100644
--- a/compiler/rustc_hir_analysis/src/check_unused.rs
+++ b/compiler/rustc_hir_analysis/src/check_unused.rs
@@ -1,5 +1,6 @@
 use crate::errors::{ExternCrateNotIdiomatic, UnusedExternCrate};
-use rustc_data_structures::fx::{FxHashMap, FxHashSet};
+use rustc_data_structures::fx::FxHashMap;
+use rustc_data_structures::unord::UnordSet;
 use rustc_hir as hir;
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::{DefId, LocalDefId};
@@ -8,12 +9,12 @@ use rustc_session::lint;
 use rustc_span::{Span, Symbol};
 
 pub fn check_crate(tcx: TyCtxt<'_>) {
-    let mut used_trait_imports: FxHashSet<LocalDefId> = FxHashSet::default();
+    let mut used_trait_imports: UnordSet<LocalDefId> = Default::default();
 
     for item_def_id in tcx.hir().body_owners() {
         let imports = tcx.used_trait_imports(item_def_id);
         debug!("GatherVisitor: item_def_id={:?} with imports {:#?}", item_def_id, imports);
-        used_trait_imports.extend(imports.iter());
+        used_trait_imports.extend(imports.items().copied());
     }
 
     for &id in tcx.maybe_unused_trait_imports(()) {
@@ -89,11 +90,11 @@ fn unused_crates_lint(tcx: TyCtxt<'_>) {
     let mut crates_to_lint = vec![];
 
     for id in tcx.hir().items() {
-        if matches!(tcx.def_kind(id.def_id), DefKind::ExternCrate) {
+        if matches!(tcx.def_kind(id.owner_id), DefKind::ExternCrate) {
             let item = tcx.hir().item(id);
             if let hir::ItemKind::ExternCrate(orig_name) = item.kind {
                 crates_to_lint.push(ExternCrateToLint {
-                    def_id: item.def_id.to_def_id(),
+                    def_id: item.owner_id.to_def_id(),
                     span: item.span,
                     orig_name,
                     warn_if_unused: !item.ident.as_str().starts_with('_'),
diff --git a/compiler/rustc_hir_analysis/src/coherence/builtin.rs b/compiler/rustc_hir_analysis/src/coherence/builtin.rs
index b6c91d425dff..6f74ef3ccad6 100644
--- a/compiler/rustc_hir_analysis/src/coherence/builtin.rs
+++ b/compiler/rustc_hir_analysis/src/coherence/builtin.rs
@@ -321,7 +321,7 @@ fn visit_implementation_of_dispatch_from_dyn<'tcx>(tcx: TyCtxt<'tcx>, impl_did:
                     }),
                 );
                 if !errors.is_empty() {
-                    infcx.err_ctxt().report_fulfillment_errors(&errors, None, false);
+                    infcx.err_ctxt().report_fulfillment_errors(&errors, None);
                 }
 
                 // Finally, resolve all regions.
@@ -561,7 +561,7 @@ pub fn coerce_unsized_info<'tcx>(tcx: TyCtxt<'tcx>, impl_did: DefId) -> CoerceUn
         predicate_for_trait_def(tcx, param_env, cause, trait_def_id, 0, source, &[target.into()]);
     let errors = traits::fully_solve_obligation(&infcx, predicate);
     if !errors.is_empty() {
-        infcx.err_ctxt().report_fulfillment_errors(&errors, None, false);
+        infcx.err_ctxt().report_fulfillment_errors(&errors, None);
     }
 
     // Finally, resolve all regions.
diff --git a/compiler/rustc_hir_analysis/src/coherence/inherent_impls.rs b/compiler/rustc_hir_analysis/src/coherence/inherent_impls.rs
index 308ad5d5fc2c..2890c149b3af 100644
--- a/compiler/rustc_hir_analysis/src/coherence/inherent_impls.rs
+++ b/compiler/rustc_hir_analysis/src/coherence/inherent_impls.rs
@@ -58,7 +58,7 @@ const ADD_ATTR: &str =
 
 impl<'tcx> InherentCollect<'tcx> {
     fn check_def_id(&mut self, item: &hir::Item<'_>, self_ty: Ty<'tcx>, def_id: DefId) {
-        let impl_def_id = item.def_id;
+        let impl_def_id = item.owner_id;
         if let Some(def_id) = def_id.as_local() {
             // Add the implementation to the mapping from implementation to base
             // type def ID, if there is a base type for this implementation and
@@ -89,7 +89,7 @@ impl<'tcx> InherentCollect<'tcx> {
             for impl_item in items {
                 if !self
                     .tcx
-                    .has_attr(impl_item.id.def_id.to_def_id(), sym::rustc_allow_incoherent_impl)
+                    .has_attr(impl_item.id.owner_id.to_def_id(), sym::rustc_allow_incoherent_impl)
                 {
                     struct_span_err!(
                         self.tcx.sess,
@@ -135,7 +135,7 @@ impl<'tcx> InherentCollect<'tcx> {
                 for item in items {
                     if !self
                         .tcx
-                        .has_attr(item.id.def_id.to_def_id(), sym::rustc_allow_incoherent_impl)
+                        .has_attr(item.id.owner_id.to_def_id(), sym::rustc_allow_incoherent_impl)
                     {
                         struct_span_err!(
                             self.tcx.sess,
@@ -177,7 +177,7 @@ impl<'tcx> InherentCollect<'tcx> {
     }
 
     fn check_item(&mut self, id: hir::ItemId) {
-        if !matches!(self.tcx.def_kind(id.def_id), DefKind::Impl) {
+        if !matches!(self.tcx.def_kind(id.owner_id), DefKind::Impl) {
             return;
         }
 
@@ -186,7 +186,7 @@ impl<'tcx> InherentCollect<'tcx> {
             return;
         };
 
-        let self_ty = self.tcx.type_of(item.def_id);
+        let self_ty = self.tcx.type_of(item.owner_id);
         match *self_ty.kind() {
             ty::Adt(def, _) => {
                 self.check_def_id(item, self_ty, def.did());
@@ -221,7 +221,7 @@ impl<'tcx> InherentCollect<'tcx> {
             | ty::Never
             | ty::FnPtr(_)
             | ty::Tuple(..) => {
-                self.check_primitive_impl(item.def_id.def_id, self_ty, items, ty.span)
+                self.check_primitive_impl(item.owner_id.def_id, self_ty, items, ty.span)
             }
             ty::Projection(..) | ty::Opaque(..) | ty::Param(_) => {
                 let mut err = struct_span_err!(
@@ -243,7 +243,7 @@ impl<'tcx> InherentCollect<'tcx> {
             | ty::Bound(..)
             | ty::Placeholder(_)
             | ty::Infer(_) => {
-                bug!("unexpected impl self type of impl: {:?} {:?}", item.def_id, self_ty);
+                bug!("unexpected impl self type of impl: {:?} {:?}", item.owner_id, self_ty);
             }
             ty::Error(_) => {}
         }
diff --git a/compiler/rustc_hir_analysis/src/coherence/inherent_impls_overlap.rs b/compiler/rustc_hir_analysis/src/coherence/inherent_impls_overlap.rs
index 130eb8005b06..972769eb1970 100644
--- a/compiler/rustc_hir_analysis/src/coherence/inherent_impls_overlap.rs
+++ b/compiler/rustc_hir_analysis/src/coherence/inherent_impls_overlap.rs
@@ -156,14 +156,14 @@ impl<'tcx> InherentOverlapChecker<'tcx> {
     }
 
     fn check_item(&mut self, id: hir::ItemId) {
-        let def_kind = self.tcx.def_kind(id.def_id);
+        let def_kind = self.tcx.def_kind(id.owner_id);
         if !matches!(def_kind, DefKind::Enum | DefKind::Struct | DefKind::Trait | DefKind::Union) {
             return;
         }
 
-        let impls = self.tcx.inherent_impls(id.def_id);
+        let impls = self.tcx.inherent_impls(id.owner_id);
 
-        let overlap_mode = OverlapMode::get(self.tcx, id.def_id.to_def_id());
+        let overlap_mode = OverlapMode::get(self.tcx, id.owner_id.to_def_id());
 
         let impls_items = impls
             .iter()
diff --git a/compiler/rustc_hir_analysis/src/coherence/mod.rs b/compiler/rustc_hir_analysis/src/coherence/mod.rs
index ae9ebe590914..1bf3768fead3 100644
--- a/compiler/rustc_hir_analysis/src/coherence/mod.rs
+++ b/compiler/rustc_hir_analysis/src/coherence/mod.rs
@@ -5,10 +5,11 @@
 // done by the orphan and overlap modules. Then we build up various
 // mappings. That mapping code resides here.
 
-use rustc_errors::struct_span_err;
+use rustc_errors::{error_code, struct_span_err};
 use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_middle::ty::query::Providers;
 use rustc_middle::ty::{self, TyCtxt, TypeVisitable};
+use rustc_span::sym;
 use rustc_trait_selection::traits;
 
 mod builtin;
@@ -39,61 +40,26 @@ fn enforce_trait_manually_implementable(
     impl_def_id: LocalDefId,
     trait_def_id: DefId,
 ) {
-    let did = Some(trait_def_id);
-    let li = tcx.lang_items();
     let impl_header_span = tcx.def_span(impl_def_id);
 
-    // Disallow *all* explicit impls of `Pointee`, `DiscriminantKind`, `Sized` and `Unsize` for now.
-    if did == li.pointee_trait() {
-        struct_span_err!(
+    // Disallow *all* explicit impls of traits marked `#[rustc_deny_explicit_impl]`
+    if tcx.has_attr(trait_def_id, sym::rustc_deny_explicit_impl) {
+        let trait_name = tcx.item_name(trait_def_id);
+        let mut err = struct_span_err!(
             tcx.sess,
             impl_header_span,
             E0322,
-            "explicit impls for the `Pointee` trait are not permitted"
-        )
-        .span_label(impl_header_span, "impl of `Pointee` not allowed")
-        .emit();
-        return;
-    }
+            "explicit impls for the `{trait_name}` trait are not permitted"
+        );
+        err.span_label(impl_header_span, format!("impl of `{trait_name}` not allowed"));
 
-    if did == li.discriminant_kind_trait() {
-        struct_span_err!(
-            tcx.sess,
-            impl_header_span,
-            E0322,
-            "explicit impls for the `DiscriminantKind` trait are not permitted"
-        )
-        .span_label(impl_header_span, "impl of `DiscriminantKind` not allowed")
-        .emit();
-        return;
-    }
+        // Maintain explicit error code for `Unsize`, since it has a useful
+        // explanation about using `CoerceUnsized` instead.
+        if Some(trait_def_id) == tcx.lang_items().unsize_trait() {
+            err.code(error_code!(E0328));
+        }
 
-    if did == li.sized_trait() {
-        struct_span_err!(
-            tcx.sess,
-            impl_header_span,
-            E0322,
-            "explicit impls for the `Sized` trait are not permitted"
-        )
-        .span_label(impl_header_span, "impl of `Sized` not allowed")
-        .emit();
-        return;
-    }
-
-    if did == li.unsize_trait() {
-        struct_span_err!(
-            tcx.sess,
-            impl_header_span,
-            E0328,
-            "explicit impls for the `Unsize` trait are not permitted"
-        )
-        .span_label(impl_header_span, "impl of `Unsize` not allowed")
-        .emit();
-        return;
-    }
-
-    if tcx.features().unboxed_closures {
-        // the feature gate allows all Fn traits
+        err.emit();
         return;
     }
 
diff --git a/compiler/rustc_hir_analysis/src/coherence/orphan.rs b/compiler/rustc_hir_analysis/src/coherence/orphan.rs
index 1307f74f2107..71c932d747bc 100644
--- a/compiler/rustc_hir_analysis/src/coherence/orphan.rs
+++ b/compiler/rustc_hir_analysis/src/coherence/orphan.rs
@@ -23,9 +23,7 @@ pub(crate) fn orphan_check_impl(
     impl_def_id: LocalDefId,
 ) -> Result<(), ErrorGuaranteed> {
     let trait_ref = tcx.impl_trait_ref(impl_def_id).unwrap();
-    if let Some(err) = trait_ref.error_reported() {
-        return Err(err);
-    }
+    trait_ref.error_reported()?;
 
     let ret = do_orphan_check_impl(tcx, trait_ref, impl_def_id);
     if tcx.trait_is_auto(trait_ref.def_id) {
@@ -101,7 +99,7 @@ fn do_orphan_check_impl<'tcx>(
         span_bug!(sp, "opaque type not found, but `has_opaque_types` is set")
     }
 
-    match traits::orphan_check(tcx, item.def_id.to_def_id()) {
+    match traits::orphan_check(tcx, item.owner_id.to_def_id()) {
         Ok(()) => {}
         Err(err) => emit_orphan_check_error(
             tcx,
diff --git a/compiler/rustc_hir_analysis/src/coherence/unsafety.rs b/compiler/rustc_hir_analysis/src/coherence/unsafety.rs
index e45fb5fe41c0..a34815b45b3a 100644
--- a/compiler/rustc_hir_analysis/src/coherence/unsafety.rs
+++ b/compiler/rustc_hir_analysis/src/coherence/unsafety.rs
@@ -13,7 +13,7 @@ pub(super) fn check_item(tcx: TyCtxt<'_>, def_id: LocalDefId) {
     let item = tcx.hir().expect_item(def_id);
     let hir::ItemKind::Impl(ref impl_) = item.kind else { bug!() };
 
-    if let Some(trait_ref) = tcx.impl_trait_ref(item.def_id) {
+    if let Some(trait_ref) = tcx.impl_trait_ref(item.owner_id) {
         let trait_def = tcx.trait_def(trait_ref.def_id);
         let unsafe_attr =
             impl_.generics.params.iter().find(|p| p.pure_wrt_drop).map(|_| "may_dangle");
@@ -26,6 +26,12 @@ pub(super) fn check_item(tcx: TyCtxt<'_>, def_id: LocalDefId) {
                     "implementing the trait `{}` is not unsafe",
                     trait_ref.print_only_trait_path()
                 )
+                .span_suggestion_verbose(
+                    item.span.with_hi(item.span.lo() + rustc_span::BytePos(7)),
+                    "remove `unsafe` from this trait implementation",
+                    "",
+                    rustc_errors::Applicability::MachineApplicable,
+                )
                 .emit();
             }
 
@@ -37,6 +43,18 @@ pub(super) fn check_item(tcx: TyCtxt<'_>, def_id: LocalDefId) {
                     "the trait `{}` requires an `unsafe impl` declaration",
                     trait_ref.print_only_trait_path()
                 )
+                .note(format!(
+                    "the trait `{}` enforces invariants that the compiler can't check. \
+                    Review the trait documentation and make sure this implementation \
+                    upholds those invariants before adding the `unsafe` keyword",
+                    trait_ref.print_only_trait_path()
+                ))
+                .span_suggestion_verbose(
+                    item.span.shrink_to_lo(),
+                    "add `unsafe` to this trait implementation",
+                    "unsafe ",
+                    rustc_errors::Applicability::MaybeIncorrect,
+                )
                 .emit();
             }
 
@@ -48,6 +66,18 @@ pub(super) fn check_item(tcx: TyCtxt<'_>, def_id: LocalDefId) {
                     "requires an `unsafe impl` declaration due to `#[{}]` attribute",
                     attr_name
                 )
+                .note(format!(
+                    "the trait `{}` enforces invariants that the compiler can't check. \
+                    Review the trait documentation and make sure this implementation \
+                    upholds those invariants before adding the `unsafe` keyword",
+                    trait_ref.print_only_trait_path()
+                ))
+                .span_suggestion_verbose(
+                    item.span.shrink_to_lo(),
+                    "add `unsafe` to this trait implementation",
+                    "unsafe ",
+                    rustc_errors::Applicability::MaybeIncorrect,
+                )
                 .emit();
             }
 
diff --git a/compiler/rustc_hir_analysis/src/collect.rs b/compiler/rustc_hir_analysis/src/collect.rs
index 66ca7d7aa08f..0e7a5ebf5ab6 100644
--- a/compiler/rustc_hir_analysis/src/collect.rs
+++ b/compiler/rustc_hir_analysis/src/collect.rs
@@ -27,8 +27,8 @@ use rustc_hir as hir;
 use rustc_hir::def::CtorKind;
 use rustc_hir::def_id::{DefId, LocalDefId, LOCAL_CRATE};
 use rustc_hir::intravisit::{self, Visitor};
-use rustc_hir::weak_lang_items;
-use rustc_hir::{GenericParamKind, Node};
+use rustc_hir::weak_lang_items::WEAK_LANG_ITEMS;
+use rustc_hir::{lang_items, GenericParamKind, LangItem, Node};
 use rustc_middle::hir::nested_filter;
 use rustc_middle::middle::codegen_fn_attrs::{CodegenFnAttrFlags, CodegenFnAttrs};
 use rustc_middle::mir::mono::Linkage;
@@ -379,8 +379,8 @@ impl<'tcx> AstConv<'tcx> for ItemCtxt<'tcx> {
         self.tcx
     }
 
-    fn item_def_id(&self) -> Option<DefId> {
-        Some(self.item_def_id)
+    fn item_def_id(&self) -> DefId {
+        self.item_def_id
     }
 
     fn get_type_parameter_bounds(
@@ -512,8 +512,7 @@ impl<'tcx> AstConv<'tcx> for ItemCtxt<'tcx> {
                 }
                 _ => {}
             }
-            err.emit();
-            self.tcx().ty_error()
+            self.tcx().ty_error_with_guaranteed(err.emit())
         }
     }
 
@@ -571,7 +570,7 @@ fn get_new_lifetime_name<'tcx>(
 fn convert_item(tcx: TyCtxt<'_>, item_id: hir::ItemId) {
     let it = tcx.hir().item(item_id);
     debug!("convert: item {} with id {}", it.ident, it.hir_id());
-    let def_id = item_id.def_id.def_id;
+    let def_id = item_id.owner_id.def_id;
 
     match it.kind {
         // These don't define types.
@@ -583,11 +582,11 @@ fn convert_item(tcx: TyCtxt<'_>, item_id: hir::ItemId) {
         hir::ItemKind::ForeignMod { items, .. } => {
             for item in items {
                 let item = tcx.hir().foreign_item(item.id);
-                tcx.ensure().generics_of(item.def_id);
-                tcx.ensure().type_of(item.def_id);
-                tcx.ensure().predicates_of(item.def_id);
+                tcx.ensure().generics_of(item.owner_id);
+                tcx.ensure().type_of(item.owner_id);
+                tcx.ensure().predicates_of(item.owner_id);
                 match item.kind {
-                    hir::ForeignItemKind::Fn(..) => tcx.ensure().fn_sig(item.def_id),
+                    hir::ForeignItemKind::Fn(..) => tcx.ensure().fn_sig(item.owner_id),
                     hir::ForeignItemKind::Static(..) => {
                         let mut visitor = HirPlaceholderCollector::default();
                         visitor.visit_foreign_item(item);
@@ -604,11 +603,11 @@ fn convert_item(tcx: TyCtxt<'_>, item_id: hir::ItemId) {
                 }
             }
         }
-        hir::ItemKind::Enum(ref enum_definition, _) => {
+        hir::ItemKind::Enum(..) => {
             tcx.ensure().generics_of(def_id);
             tcx.ensure().type_of(def_id);
             tcx.ensure().predicates_of(def_id);
-            convert_enum_variant_types(tcx, def_id.to_def_id(), enum_definition.variants);
+            convert_enum_variant_types(tcx, def_id.to_def_id());
         }
         hir::ItemKind::Impl { .. } => {
             tcx.ensure().generics_of(def_id);
@@ -640,16 +639,11 @@ fn convert_item(tcx: TyCtxt<'_>, item_id: hir::ItemId) {
             }
 
             if let Some(ctor_hir_id) = struct_def.ctor_hir_id() {
-                convert_variant_ctor(tcx, ctor_hir_id);
+                let ctor_def_id = tcx.hir().local_def_id(ctor_hir_id);
+                convert_variant_ctor(tcx, ctor_def_id);
             }
         }
 
-        // Desugared from `impl Trait`, so visited by the function's return type.
-        hir::ItemKind::OpaqueTy(hir::OpaqueTy {
-            origin: hir::OpaqueTyOrigin::FnReturn(..) | hir::OpaqueTyOrigin::AsyncFn(..),
-            ..
-        }) => {}
-
         // Don't call `type_of` on opaque types, since that depends on type
         // checking function bodies. `check_item_type` ensures that it's called
         // instead.
@@ -657,33 +651,38 @@ fn convert_item(tcx: TyCtxt<'_>, item_id: hir::ItemId) {
             tcx.ensure().generics_of(def_id);
             tcx.ensure().predicates_of(def_id);
             tcx.ensure().explicit_item_bounds(def_id);
+            tcx.ensure().item_bounds(def_id);
         }
-        hir::ItemKind::TyAlias(..)
-        | hir::ItemKind::Static(..)
-        | hir::ItemKind::Const(..)
-        | hir::ItemKind::Fn(..) => {
+
+        hir::ItemKind::TyAlias(..) => {
             tcx.ensure().generics_of(def_id);
             tcx.ensure().type_of(def_id);
             tcx.ensure().predicates_of(def_id);
-            match it.kind {
-                hir::ItemKind::Fn(..) => tcx.ensure().fn_sig(def_id),
-                hir::ItemKind::OpaqueTy(..) => tcx.ensure().item_bounds(def_id),
-                hir::ItemKind::Const(ty, ..) | hir::ItemKind::Static(ty, ..) => {
-                    if !is_suggestable_infer_ty(ty) {
-                        let mut visitor = HirPlaceholderCollector::default();
-                        visitor.visit_item(it);
-                        placeholder_type_error(tcx, None, visitor.0, false, None, it.kind.descr());
-                    }
-                }
-                _ => (),
+        }
+
+        hir::ItemKind::Static(ty, ..) | hir::ItemKind::Const(ty, ..) => {
+            tcx.ensure().generics_of(def_id);
+            tcx.ensure().type_of(def_id);
+            tcx.ensure().predicates_of(def_id);
+            if !is_suggestable_infer_ty(ty) {
+                let mut visitor = HirPlaceholderCollector::default();
+                visitor.visit_item(it);
+                placeholder_type_error(tcx, None, visitor.0, false, None, it.kind.descr());
             }
         }
+
+        hir::ItemKind::Fn(..) => {
+            tcx.ensure().generics_of(def_id);
+            tcx.ensure().type_of(def_id);
+            tcx.ensure().predicates_of(def_id);
+            tcx.ensure().fn_sig(def_id);
+        }
     }
 }
 
 fn convert_trait_item(tcx: TyCtxt<'_>, trait_item_id: hir::TraitItemId) {
     let trait_item = tcx.hir().trait_item(trait_item_id);
-    let def_id = trait_item_id.def_id;
+    let def_id = trait_item_id.owner_id;
     tcx.ensure().generics_of(def_id);
 
     match trait_item.kind {
@@ -730,7 +729,7 @@ fn convert_trait_item(tcx: TyCtxt<'_>, trait_item_id: hir::TraitItemId) {
 }
 
 fn convert_impl_item(tcx: TyCtxt<'_>, impl_item_id: hir::ImplItemId) {
-    let def_id = impl_item_id.def_id;
+    let def_id = impl_item_id.owner_id;
     tcx.ensure().generics_of(def_id);
     tcx.ensure().type_of(def_id);
     tcx.ensure().predicates_of(def_id);
@@ -750,37 +749,34 @@ fn convert_impl_item(tcx: TyCtxt<'_>, impl_item_id: hir::ImplItemId) {
     }
 }
 
-fn convert_variant_ctor(tcx: TyCtxt<'_>, ctor_id: hir::HirId) {
-    let def_id = tcx.hir().local_def_id(ctor_id);
+fn convert_variant_ctor(tcx: TyCtxt<'_>, def_id: LocalDefId) {
     tcx.ensure().generics_of(def_id);
     tcx.ensure().type_of(def_id);
     tcx.ensure().predicates_of(def_id);
 }
 
-fn convert_enum_variant_types(tcx: TyCtxt<'_>, def_id: DefId, variants: &[hir::Variant<'_>]) {
+fn convert_enum_variant_types(tcx: TyCtxt<'_>, def_id: DefId) {
     let def = tcx.adt_def(def_id);
     let repr_type = def.repr().discr_type();
     let initial = repr_type.initial_discriminant(tcx);
     let mut prev_discr = None::<Discr<'_>>;
 
     // fill the discriminant values and field types
-    for variant in variants {
+    for variant in def.variants() {
         let wrapped_discr = prev_discr.map_or(initial, |d| d.wrap_incr(tcx));
         prev_discr = Some(
-            if let Some(ref e) = variant.disr_expr {
-                let expr_did = tcx.hir().local_def_id(e.hir_id);
-                def.eval_explicit_discr(tcx, expr_did.to_def_id())
+            if let ty::VariantDiscr::Explicit(const_def_id) = variant.discr {
+                def.eval_explicit_discr(tcx, const_def_id)
             } else if let Some(discr) = repr_type.disr_incr(tcx, prev_discr) {
                 Some(discr)
             } else {
-                struct_span_err!(tcx.sess, variant.span, E0370, "enum discriminant overflowed")
-                    .span_label(
-                        variant.span,
-                        format!("overflowed on value after {}", prev_discr.unwrap()),
-                    )
+                let span = tcx.def_span(variant.def_id);
+                struct_span_err!(tcx.sess, span, E0370, "enum discriminant overflowed")
+                    .span_label(span, format!("overflowed on value after {}", prev_discr.unwrap()))
                     .note(&format!(
                         "explicitly set `{} = {}` if that is desired outcome",
-                        variant.ident, wrapped_discr
+                        tcx.item_name(variant.def_id),
+                        wrapped_discr
                     ))
                     .emit();
                 None
@@ -788,17 +784,16 @@ fn convert_enum_variant_types(tcx: TyCtxt<'_>, def_id: DefId, variants: &[hir::V
             .unwrap_or(wrapped_discr),
         );
 
-        for f in variant.data.fields() {
-            let def_id = tcx.hir().local_def_id(f.hir_id);
-            tcx.ensure().generics_of(def_id);
-            tcx.ensure().type_of(def_id);
-            tcx.ensure().predicates_of(def_id);
+        for f in &variant.fields {
+            tcx.ensure().generics_of(f.did);
+            tcx.ensure().type_of(f.did);
+            tcx.ensure().predicates_of(f.did);
         }
 
         // Convert the ctor, if any. This also registers the variant as
         // an item.
-        if let Some(ctor_hir_id) = variant.data.ctor_hir_id() {
-            convert_variant_ctor(tcx, ctor_hir_id);
+        if let Some(ctor_def_id) = variant.ctor_def_id {
+            convert_variant_ctor(tcx, ctor_def_id.expect_local());
         }
     }
 }
@@ -1010,7 +1005,7 @@ fn trait_def(tcx: TyCtxt<'_>, def_id: DefId) -> ty::TraitDef {
 
                 match item {
                     Some(item) if matches!(item.kind, hir::AssocItemKind::Fn { .. }) => {
-                        if !tcx.impl_defaultness(item.id.def_id).has_value() {
+                        if !tcx.impl_defaultness(item.id.owner_id).has_value() {
                             tcx.sess
                                 .struct_span_err(
                                     item.span,
@@ -1143,7 +1138,7 @@ fn fn_sig(tcx: TyCtxt<'_>, def_id: DefId) -> ty::PolyFnSig<'_> {
         }
 
         ImplItem(hir::ImplItem { kind: ImplItemKind::Fn(sig, _), generics, .. }) => {
-            // Do not try to inference the return type for a impl method coming from a trait
+            // Do not try to infer the return type for a impl method coming from a trait
             if let Item(hir::Item { kind: ItemKind::Impl(i), .. }) =
                 tcx.hir().get(tcx.hir().get_parent_node(hir_id))
                 && i.of_trait.is_some()
@@ -1286,15 +1281,46 @@ fn infer_return_ty_for_fn_sig<'tcx>(
 
 fn impl_trait_ref(tcx: TyCtxt<'_>, def_id: DefId) -> Option<ty::TraitRef<'_>> {
     let icx = ItemCtxt::new(tcx, def_id);
-    match tcx.hir().expect_item(def_id.expect_local()).kind {
+    let item = tcx.hir().expect_item(def_id.expect_local());
+    match item.kind {
         hir::ItemKind::Impl(ref impl_) => impl_.of_trait.as_ref().map(|ast_trait_ref| {
             let selfty = tcx.type_of(def_id);
-            <dyn AstConv<'_>>::instantiate_mono_trait_ref(&icx, ast_trait_ref, selfty)
+            <dyn AstConv<'_>>::instantiate_mono_trait_ref(
+                &icx,
+                ast_trait_ref,
+                selfty,
+                check_impl_constness(tcx, impl_.constness, ast_trait_ref),
+            )
         }),
         _ => bug!(),
     }
 }
 
+fn check_impl_constness(
+    tcx: TyCtxt<'_>,
+    constness: hir::Constness,
+    ast_trait_ref: &hir::TraitRef<'_>,
+) -> ty::BoundConstness {
+    match constness {
+        hir::Constness::Const => {
+            if let Some(trait_def_id) = ast_trait_ref.trait_def_id() && !tcx.has_attr(trait_def_id, sym::const_trait) {
+                let trait_name = tcx.item_name(trait_def_id).to_string();
+                tcx.sess.emit_err(errors::ConstImplForNonConstTrait {
+                    trait_ref_span: ast_trait_ref.path.span,
+                    trait_name,
+                    local_trait_span: trait_def_id.as_local().map(|_| tcx.def_span(trait_def_id).shrink_to_lo()),
+                    marking: (),
+                    adding: (),
+                });
+                ty::BoundConstness::NotConst
+            } else {
+                ty::BoundConstness::ConstIfConst
+            }
+        },
+        hir::Constness::NotConst => ty::BoundConstness::NotConst,
+    }
+}
+
 fn impl_polarity(tcx: TyCtxt<'_>, def_id: DefId) -> ty::ImplPolarity {
     let is_rustc_reservation = tcx.has_attr(def_id, sym::rustc_reservation_impl);
     let item = tcx.hir().expect_item(def_id.expect_local());
@@ -2073,12 +2099,15 @@ fn codegen_fn_attrs(tcx: TyCtxt<'_>, did: DefId) -> CodegenFnAttrs {
     // strippable by the linker.
     //
     // Additionally weak lang items have predetermined symbol names.
-    if tcx.is_weak_lang_item(did.to_def_id()) {
+    if WEAK_LANG_ITEMS.iter().any(|&l| tcx.lang_items().get(l) == Some(did.to_def_id())) {
         codegen_fn_attrs.flags |= CodegenFnAttrFlags::RUSTC_STD_INTERNAL_SYMBOL;
     }
-    if let Some(name) = weak_lang_items::link_name(attrs) {
-        codegen_fn_attrs.export_name = Some(name);
-        codegen_fn_attrs.link_name = Some(name);
+    if let Some((name, _)) = lang_items::extract(attrs)
+        && let Some(lang_item) = LangItem::from_name(name)
+        && let Some(link_name) = lang_item.link_name()
+    {
+        codegen_fn_attrs.export_name = Some(link_name);
+        codegen_fn_attrs.link_name = Some(link_name);
     }
     check_link_name_xor_ordinal(tcx, &codegen_fn_attrs, link_ordinal_span);
 
diff --git a/compiler/rustc_hir_analysis/src/collect/generics_of.rs b/compiler/rustc_hir_analysis/src/collect/generics_of.rs
index 707fd6c75278..c7777a946893 100644
--- a/compiler/rustc_hir_analysis/src/collect/generics_of.rs
+++ b/compiler/rustc_hir_analysis/src/collect/generics_of.rs
@@ -249,6 +249,11 @@ pub(super) fn generics_of(tcx: TyCtxt<'_>, def_id: DefId) -> ty::Generics {
     // Now create the real type and const parameters.
     let type_start = own_start - has_self as u32 + params.len() as u32;
     let mut i = 0;
+    let mut next_index = || {
+        let prev = i;
+        i += 1;
+        prev as u32 + type_start
+    };
 
     const TYPE_DEFAULT_NOT_ALLOWED: &'static str = "defaults for type parameters are only allowed in \
     `struct`, `enum`, `type`, or `trait` definitions";
@@ -278,15 +283,13 @@ pub(super) fn generics_of(tcx: TyCtxt<'_>, def_id: DefId) -> ty::Generics {
 
             let kind = ty::GenericParamDefKind::Type { has_default: default.is_some(), synthetic };
 
-            let param_def = ty::GenericParamDef {
-                index: type_start + i as u32,
+            Some(ty::GenericParamDef {
+                index: next_index(),
                 name: param.name.ident().name,
                 def_id: tcx.hir().local_def_id(param.hir_id).to_def_id(),
                 pure_wrt_drop: param.pure_wrt_drop,
                 kind,
-            };
-            i += 1;
-            Some(param_def)
+            })
         }
         GenericParamKind::Const { default, .. } => {
             if !matches!(allow_defaults, Defaults::Allowed) && default.is_some() {
@@ -297,15 +300,13 @@ pub(super) fn generics_of(tcx: TyCtxt<'_>, def_id: DefId) -> ty::Generics {
                 );
             }
 
-            let param_def = ty::GenericParamDef {
-                index: type_start + i as u32,
+            Some(ty::GenericParamDef {
+                index: next_index(),
                 name: param.name.ident().name,
                 def_id: tcx.hir().local_def_id(param.hir_id).to_def_id(),
                 pure_wrt_drop: param.pure_wrt_drop,
                 kind: ty::GenericParamDefKind::Const { has_default: default.is_some() },
-            };
-            i += 1;
-            Some(param_def)
+            })
         }
     }));
 
@@ -323,8 +324,8 @@ pub(super) fn generics_of(tcx: TyCtxt<'_>, def_id: DefId) -> ty::Generics {
             &["<closure_kind>", "<closure_signature>", "<upvars>"][..]
         };
 
-        params.extend(dummy_args.iter().enumerate().map(|(i, &arg)| ty::GenericParamDef {
-            index: type_start + i as u32,
+        params.extend(dummy_args.iter().map(|&arg| ty::GenericParamDef {
+            index: next_index(),
             name: Symbol::intern(arg),
             def_id,
             pure_wrt_drop: false,
@@ -337,7 +338,7 @@ pub(super) fn generics_of(tcx: TyCtxt<'_>, def_id: DefId) -> ty::Generics {
         let parent_node = tcx.hir().get(tcx.hir().get_parent_node(hir_id));
         if let Node::Expr(&Expr { kind: ExprKind::ConstBlock(_), .. }) = parent_node {
             params.push(ty::GenericParamDef {
-                index: type_start,
+                index: next_index(),
                 name: Symbol::intern("<const_ty>"),
                 def_id,
                 pure_wrt_drop: false,
diff --git a/compiler/rustc_hir_analysis/src/collect/lifetimes.rs b/compiler/rustc_hir_analysis/src/collect/lifetimes.rs
index c1214698cf77..6ee7aa9cdac6 100644
--- a/compiler/rustc_hir_analysis/src/collect/lifetimes.rs
+++ b/compiler/rustc_hir_analysis/src/collect/lifetimes.rs
@@ -18,7 +18,7 @@ use rustc_middle::bug;
 use rustc_middle::hir::map::Map;
 use rustc_middle::hir::nested_filter;
 use rustc_middle::middle::resolve_lifetime::*;
-use rustc_middle::ty::{self, DefIdTree, TyCtxt};
+use rustc_middle::ty::{self, DefIdTree, TyCtxt, TypeSuperVisitable, TypeVisitor};
 use rustc_span::def_id::DefId;
 use rustc_span::symbol::{sym, Ident};
 use rustc_span::Span;
@@ -94,11 +94,6 @@ struct LifetimeContext<'a, 'tcx> {
     tcx: TyCtxt<'tcx>,
     map: &'a mut NamedRegionMap,
     scope: ScopeRef<'a>,
-
-    /// Indicates that we only care about the definition of a trait. This should
-    /// be false if the `Item` we are resolving lifetimes for is not a trait or
-    /// we eventually need lifetimes resolve for trait items.
-    trait_definition_only: bool,
 }
 
 #[derive(Debug)]
@@ -166,7 +161,9 @@ enum Scope<'a> {
         s: ScopeRef<'a>,
     },
 
-    Root,
+    Root {
+        opt_parent_item: Option<LocalDefId>,
+    },
 }
 
 #[derive(Copy, Clone, Debug)]
@@ -214,95 +211,58 @@ impl<'a> fmt::Debug for TruncatedScopeDebug<'a> {
                 .field("s", &"..")
                 .finish(),
             Scope::TraitRefBoundary { s: _ } => f.debug_struct("TraitRefBoundary").finish(),
-            Scope::Root => f.debug_struct("Root").finish(),
+            Scope::Root { opt_parent_item } => {
+                f.debug_struct("Root").field("opt_parent_item", &opt_parent_item).finish()
+            }
         }
     }
 }
 
 type ScopeRef<'a> = &'a Scope<'a>;
 
-const ROOT_SCOPE: ScopeRef<'static> = &Scope::Root;
-
 pub(crate) fn provide(providers: &mut ty::query::Providers) {
     *providers = ty::query::Providers {
-        resolve_lifetimes_trait_definition,
         resolve_lifetimes,
 
-        named_region_map: |tcx, id| resolve_lifetimes_for(tcx, id).defs.get(&id),
+        named_region_map: |tcx, id| tcx.resolve_lifetimes(id).defs.get(&id),
         is_late_bound_map,
         object_lifetime_default,
-        late_bound_vars_map: |tcx, id| resolve_lifetimes_for(tcx, id).late_bound_vars.get(&id),
+        late_bound_vars_map: |tcx, id| tcx.resolve_lifetimes(id).late_bound_vars.get(&id),
 
         ..*providers
     };
 }
 
-/// Like `resolve_lifetimes`, but does not resolve lifetimes for trait items.
-/// Also does not generate any diagnostics.
-///
-/// This is ultimately a subset of the `resolve_lifetimes` work. It effectively
-/// resolves lifetimes only within the trait "header" -- that is, the trait
-/// and supertrait list. In contrast, `resolve_lifetimes` resolves all the
-/// lifetimes within the trait and its items. There is room to refactor this,
-/// for example to resolve lifetimes for each trait item in separate queries,
-/// but it's convenient to do the entire trait at once because the lifetimes
-/// from the trait definition are in scope within the trait items as well.
-///
-/// The reason for this separate call is to resolve what would otherwise
-/// be a cycle. Consider this example:
-///
-/// ```ignore UNSOLVED (maybe @jackh726 knows what lifetime parameter to give Sub)
-/// trait Base<'a> {
-///     type BaseItem;
-/// }
-/// trait Sub<'b>: for<'a> Base<'a> {
-///    type SubItem: Sub<BaseItem = &'b u32>;
-/// }
-/// ```
-///
-/// When we resolve `Sub` and all its items, we also have to resolve `Sub<BaseItem = &'b u32>`.
-/// To figure out the index of `'b`, we have to know about the supertraits
-/// of `Sub` so that we can determine that the `for<'a>` will be in scope.
-/// (This is because we -- currently at least -- flatten all the late-bound
-/// lifetimes into a single binder.) This requires us to resolve the
-/// *trait definition* of `Sub`; basically just enough lifetime information
-/// to look at the supertraits.
-#[instrument(level = "debug", skip(tcx))]
-fn resolve_lifetimes_trait_definition(
-    tcx: TyCtxt<'_>,
-    local_def_id: LocalDefId,
-) -> ResolveLifetimes {
-    convert_named_region_map(do_resolve(tcx, local_def_id, true))
-}
-
 /// Computes the `ResolveLifetimes` map that contains data for an entire `Item`.
 /// You should not read the result of this query directly, but rather use
 /// `named_region_map`, `is_late_bound_map`, etc.
 #[instrument(level = "debug", skip(tcx))]
-fn resolve_lifetimes(tcx: TyCtxt<'_>, local_def_id: LocalDefId) -> ResolveLifetimes {
-    convert_named_region_map(do_resolve(tcx, local_def_id, false))
-}
-
-fn do_resolve(
-    tcx: TyCtxt<'_>,
-    local_def_id: LocalDefId,
-    trait_definition_only: bool,
-) -> NamedRegionMap {
-    let item = tcx.hir().expect_item(local_def_id);
+fn resolve_lifetimes(tcx: TyCtxt<'_>, local_def_id: hir::OwnerId) -> ResolveLifetimes {
     let mut named_region_map =
         NamedRegionMap { defs: Default::default(), late_bound_vars: Default::default() };
     let mut visitor = LifetimeContext {
         tcx,
         map: &mut named_region_map,
-        scope: ROOT_SCOPE,
-        trait_definition_only,
+        scope: &Scope::Root { opt_parent_item: None },
     };
-    visitor.visit_item(item);
+    match tcx.hir().owner(local_def_id) {
+        hir::OwnerNode::Item(item) => visitor.visit_item(item),
+        hir::OwnerNode::ForeignItem(item) => visitor.visit_foreign_item(item),
+        hir::OwnerNode::TraitItem(item) => {
+            let scope =
+                Scope::Root { opt_parent_item: Some(tcx.local_parent(item.owner_id.def_id)) };
+            visitor.scope = &scope;
+            visitor.visit_trait_item(item)
+        }
+        hir::OwnerNode::ImplItem(item) => {
+            let scope =
+                Scope::Root { opt_parent_item: Some(tcx.local_parent(item.owner_id.def_id)) };
+            visitor.scope = &scope;
+            visitor.visit_impl_item(item)
+        }
+        hir::OwnerNode::Crate(_) => {}
+    }
 
-    named_region_map
-}
-
-fn convert_named_region_map(named_region_map: NamedRegionMap) -> ResolveLifetimes {
     let mut rl = ResolveLifetimes::default();
 
     for (hir_id, v) in named_region_map.defs {
@@ -319,53 +279,6 @@ fn convert_named_region_map(named_region_map: NamedRegionMap) -> ResolveLifetime
     rl
 }
 
-/// Given `any` owner (structs, traits, trait methods, etc.), does lifetime resolution.
-/// There are two important things this does.
-/// First, we have to resolve lifetimes for
-/// the entire *`Item`* that contains this owner, because that's the largest "scope"
-/// where we can have relevant lifetimes.
-/// Second, if we are asking for lifetimes in a trait *definition*, we use `resolve_lifetimes_trait_definition`
-/// instead of `resolve_lifetimes`, which does not descend into the trait items and does not emit diagnostics.
-/// This allows us to avoid cycles. Importantly, if we ask for lifetimes for lifetimes that have an owner
-/// other than the trait itself (like the trait methods or associated types), then we just use the regular
-/// `resolve_lifetimes`.
-fn resolve_lifetimes_for<'tcx>(tcx: TyCtxt<'tcx>, def_id: hir::OwnerId) -> &'tcx ResolveLifetimes {
-    let item_id = item_for(tcx, def_id.def_id);
-    let local_def_id = item_id.def_id.def_id;
-    if item_id.def_id == def_id {
-        let item = tcx.hir().item(item_id);
-        match item.kind {
-            hir::ItemKind::Trait(..) => tcx.resolve_lifetimes_trait_definition(local_def_id),
-            _ => tcx.resolve_lifetimes(local_def_id),
-        }
-    } else {
-        tcx.resolve_lifetimes(local_def_id)
-    }
-}
-
-/// Finds the `Item` that contains the given `LocalDefId`
-fn item_for(tcx: TyCtxt<'_>, local_def_id: LocalDefId) -> hir::ItemId {
-    match tcx.hir().find_by_def_id(local_def_id) {
-        Some(Node::Item(item)) => {
-            return item.item_id();
-        }
-        _ => {}
-    }
-    let item = {
-        let hir_id = tcx.hir().local_def_id_to_hir_id(local_def_id);
-        let mut parent_iter = tcx.hir().parent_iter(hir_id);
-        loop {
-            let node = parent_iter.next().map(|n| n.1);
-            match node {
-                Some(hir::Node::Item(item)) => break item.item_id(),
-                Some(hir::Node::Crate(_)) | None => bug!("Called `item_for` on an Item."),
-                _ => {}
-            }
-        }
-    };
-    item
-}
-
 fn late_region_as_bound_region<'tcx>(tcx: TyCtxt<'tcx>, region: &Region) -> ty::BoundVariableKind {
     match region {
         Region::LateBound(_, _, def_id) => {
@@ -383,7 +296,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> {
         let mut supertrait_lifetimes = vec![];
         loop {
             match scope {
-                Scope::Body { .. } | Scope::Root => {
+                Scope::Body { .. } | Scope::Root { .. } => {
                     break (vec![], BinderScopeType::Normal);
                 }
 
@@ -414,21 +327,12 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> {
     }
 }
 impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
-    type NestedFilter = nested_filter::All;
+    type NestedFilter = nested_filter::OnlyBodies;
 
     fn nested_visit_map(&mut self) -> Self::Map {
         self.tcx.hir()
     }
 
-    // We want to nest trait/impl items in their parent, but nothing else.
-    fn visit_nested_item(&mut self, _: hir::ItemId) {}
-
-    fn visit_trait_item_ref(&mut self, ii: &'tcx hir::TraitItemRef) {
-        if !self.trait_definition_only {
-            intravisit::walk_trait_item_ref(self, ii)
-        }
-    }
-
     fn visit_nested_body(&mut self, body: hir::BodyId) {
         let body = self.tcx.hir().body(body);
         self.with(Scope::Body { id: body.id(), s: self.scope }, |this| {
@@ -548,7 +452,9 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
                     intravisit::walk_item(this, item)
                 });
             }
-            hir::ItemKind::OpaqueTy(hir::OpaqueTy { .. }) => {
+            hir::ItemKind::OpaqueTy(hir::OpaqueTy {
+                origin: hir::OpaqueTyOrigin::TyAlias, ..
+            }) => {
                 // Opaque types are visited when we visit the
                 // `TyKind::OpaqueDef`, so that they have the lifetimes from
                 // their parent opaque_ty in scope.
@@ -557,34 +463,53 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
                 // their owner, we can keep going until we find the Item that owns that. We then
                 // conservatively add all resolved lifetimes. Otherwise we run into problems in
                 // cases like `type Foo<'a> = impl Bar<As = impl Baz + 'a>`.
-                for (_hir_id, node) in self.tcx.hir().parent_iter(item.def_id.into()) {
-                    match node {
-                        hir::Node::Item(parent_item) => {
-                            let resolved_lifetimes: &ResolveLifetimes = self.tcx.resolve_lifetimes(
-                                item_for(self.tcx, parent_item.def_id.def_id).def_id.def_id,
-                            );
-                            // We need to add *all* deps, since opaque tys may want them from *us*
-                            for (&owner, defs) in resolved_lifetimes.defs.iter() {
-                                defs.iter().for_each(|(&local_id, region)| {
-                                    self.map.defs.insert(hir::HirId { owner, local_id }, *region);
-                                });
-                            }
-                            for (&owner, late_bound_vars) in
-                                resolved_lifetimes.late_bound_vars.iter()
-                            {
-                                late_bound_vars.iter().for_each(|(&local_id, late_bound_vars)| {
-                                    self.record_late_bound_vars(
-                                        hir::HirId { owner, local_id },
-                                        late_bound_vars.clone(),
-                                    );
-                                });
-                            }
-                            break;
+                let parent_item = self.tcx.hir().get_parent_item(item.hir_id());
+                let resolved_lifetimes: &ResolveLifetimes = self.tcx.resolve_lifetimes(parent_item);
+                // We need to add *all* deps, since opaque tys may want them from *us*
+                for (&owner, defs) in resolved_lifetimes.defs.iter() {
+                    defs.iter().for_each(|(&local_id, region)| {
+                        self.map.defs.insert(hir::HirId { owner, local_id }, *region);
+                    });
+                }
+                for (&owner, late_bound_vars) in resolved_lifetimes.late_bound_vars.iter() {
+                    late_bound_vars.iter().for_each(|(&local_id, late_bound_vars)| {
+                        self.record_late_bound_vars(
+                            hir::HirId { owner, local_id },
+                            late_bound_vars.clone(),
+                        );
+                    });
+                }
+            }
+            hir::ItemKind::OpaqueTy(hir::OpaqueTy {
+                origin: hir::OpaqueTyOrigin::FnReturn(_) | hir::OpaqueTyOrigin::AsyncFn(_),
+                generics,
+                ..
+            }) => {
+                // We want to start our early-bound indices at the end of the parent scope,
+                // not including any parent `impl Trait`s.
+                let mut lifetimes = FxIndexMap::default();
+                debug!(?generics.params);
+                for param in generics.params {
+                    match param.kind {
+                        GenericParamKind::Lifetime { .. } => {
+                            let (def_id, reg) = Region::early(self.tcx.hir(), &param);
+                            lifetimes.insert(def_id, reg);
                         }
-                        hir::Node::Crate(_) => bug!("No Item about an OpaqueTy"),
-                        _ => {}
+                        GenericParamKind::Type { .. } | GenericParamKind::Const { .. } => {}
                     }
                 }
+
+                let scope = Scope::Binder {
+                    hir_id: item.hir_id(),
+                    lifetimes,
+                    s: self.scope,
+                    scope_type: BinderScopeType::Normal,
+                    where_bound_origin: None,
+                };
+                self.with(scope, |this| {
+                    let scope = Scope::TraitRefBoundary { s: this.scope };
+                    this.with(scope, |this| intravisit::walk_item(this, item))
+                });
             }
             hir::ItemKind::TyAlias(_, ref generics)
             | hir::ItemKind::Enum(_, ref generics)
@@ -609,7 +534,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
                     hir_id: item.hir_id(),
                     lifetimes,
                     scope_type: BinderScopeType::Normal,
-                    s: ROOT_SCOPE,
+                    s: self.scope,
                     where_bound_origin: None,
                 };
                 self.with(scope, |this| {
@@ -712,7 +637,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
                 //                 ^                  ^ this gets resolved in the scope of
                 //                                      the opaque_ty generics
                 let opaque_ty = self.tcx.hir().item(item_id);
-                let (generics, bounds) = match opaque_ty.kind {
+                match opaque_ty.kind {
                     hir::ItemKind::OpaqueTy(hir::OpaqueTy {
                         origin: hir::OpaqueTyOrigin::TyAlias,
                         ..
@@ -733,10 +658,8 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
                     }
                     hir::ItemKind::OpaqueTy(hir::OpaqueTy {
                         origin: hir::OpaqueTyOrigin::FnReturn(..) | hir::OpaqueTyOrigin::AsyncFn(..),
-                        ref generics,
-                        bounds,
                         ..
-                    }) => (generics, bounds),
+                    }) => {}
                     ref i => bug!("`impl Trait` pointed to non-opaque type?? {:#?}", i),
                 };
 
@@ -766,65 +689,28 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
                     // Ensure that the parent of the def is an item, not HRTB
                     let parent_id = self.tcx.hir().get_parent_node(hir_id);
                     if !parent_id.is_owner() {
-                        if !self.trait_definition_only {
-                            struct_span_err!(
-                                self.tcx.sess,
-                                lifetime.span,
-                                E0657,
-                                "`impl Trait` can only capture lifetimes \
-                                    bound at the fn or impl level"
-                            )
-                            .emit();
-                        }
+                        struct_span_err!(
+                            self.tcx.sess,
+                            lifetime.span,
+                            E0657,
+                            "`impl Trait` can only capture lifetimes bound at the fn or impl level"
+                        )
+                        .emit();
                         self.uninsert_lifetime_on_error(lifetime, def.unwrap());
                     }
                     if let hir::Node::Item(hir::Item {
                         kind: hir::ItemKind::OpaqueTy { .. }, ..
                     }) = self.tcx.hir().get(parent_id)
                     {
-                        if !self.trait_definition_only {
-                            let mut err = self.tcx.sess.struct_span_err(
-                                lifetime.span,
-                                "higher kinded lifetime bounds on nested opaque types are not supported yet",
-                            );
-                            err.span_note(self.tcx.def_span(def_id), "lifetime declared here");
-                            err.emit();
-                        }
+                        let mut err = self.tcx.sess.struct_span_err(
+                            lifetime.span,
+                            "higher kinded lifetime bounds on nested opaque types are not supported yet",
+                        );
+                        err.span_note(self.tcx.def_span(def_id), "lifetime declared here");
+                        err.emit();
                         self.uninsert_lifetime_on_error(lifetime, def.unwrap());
                     }
                 }
-
-                // We want to start our early-bound indices at the end of the parent scope,
-                // not including any parent `impl Trait`s.
-                let mut lifetimes = FxIndexMap::default();
-                debug!(?generics.params);
-                for param in generics.params {
-                    match param.kind {
-                        GenericParamKind::Lifetime { .. } => {
-                            let (def_id, reg) = Region::early(self.tcx.hir(), &param);
-                            lifetimes.insert(def_id, reg);
-                        }
-                        GenericParamKind::Type { .. } | GenericParamKind::Const { .. } => {}
-                    }
-                }
-                self.record_late_bound_vars(ty.hir_id, vec![]);
-
-                let scope = Scope::Binder {
-                    hir_id: ty.hir_id,
-                    lifetimes,
-                    s: self.scope,
-                    scope_type: BinderScopeType::Normal,
-                    where_bound_origin: None,
-                };
-                self.with(scope, |this| {
-                    let scope = Scope::TraitRefBoundary { s: this.scope };
-                    this.with(scope, |this| {
-                        this.visit_generics(generics);
-                        for bound in bounds {
-                            this.visit_param_bound(bound);
-                        }
-                    })
-                });
             }
             _ => intravisit::walk_ty(self, ty),
         }
@@ -1193,12 +1079,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> {
         F: for<'b> FnOnce(&mut LifetimeContext<'b, 'tcx>),
     {
         let LifetimeContext { tcx, map, .. } = self;
-        let mut this = LifetimeContext {
-            tcx: *tcx,
-            map,
-            scope: &wrap_scope,
-            trait_definition_only: self.trait_definition_only,
-        };
+        let mut this = LifetimeContext { tcx: *tcx, map, scope: &wrap_scope };
         let span = debug_span!("scope", scope = ?TruncatedScopeDebug(&this.scope));
         {
             let _enter = span.enter();
@@ -1303,7 +1184,13 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> {
                     scope = s;
                 }
 
-                Scope::Root => {
+                Scope::Root { opt_parent_item } => {
+                    if let Some(parent_item) = opt_parent_item
+                        && let parent_generics = self.tcx.generics_of(parent_item)
+                        && parent_generics.param_def_id_to_index.contains_key(&region_def_id.to_def_id())
+                    {
+                        break Some(Region::EarlyBound(region_def_id.to_def_id()));
+                    }
                     break None;
                 }
 
@@ -1377,11 +1264,12 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> {
             } else if let Some(body_id) = outermost_body {
                 let fn_id = self.tcx.hir().body_owner(body_id);
                 match self.tcx.hir().get(fn_id) {
-                    Node::Item(&hir::Item { kind: hir::ItemKind::Fn(..), .. })
-                    | Node::TraitItem(&hir::TraitItem {
+                    Node::Item(hir::Item { kind: hir::ItemKind::Fn(..), .. })
+                    | Node::TraitItem(hir::TraitItem {
                         kind: hir::TraitItemKind::Fn(..), ..
                     })
-                    | Node::ImplItem(&hir::ImplItem { kind: hir::ImplItemKind::Fn(..), .. }) => {
+                    | Node::ImplItem(hir::ImplItem { kind: hir::ImplItemKind::Fn(..), .. })
+                    | Node::Expr(hir::Expr { kind: hir::ExprKind::Closure(..), .. }) => {
                         let scope = self.tcx.hir().local_def_id(fn_id);
                         def = Region::Free(scope.to_def_id(), def.id().unwrap());
                     }
@@ -1416,7 +1304,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> {
                     err.emit();
                     return;
                 }
-                Scope::Root => break,
+                Scope::Root { .. } => break,
                 Scope::Binder { s, .. }
                 | Scope::Body { s, .. }
                 | Scope::Elision { s, .. }
@@ -1494,7 +1382,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> {
                 let mut scope = self.scope;
                 loop {
                     match *scope {
-                        Scope::Root => break false,
+                        Scope::Root { .. } => break false,
 
                         Scope::Body { .. } => break true,
 
@@ -1731,7 +1619,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> {
                     scope = s;
                 }
 
-                Scope::Root | Scope::Elision { .. } => break Region::Static,
+                Scope::Root { .. } | Scope::Elision { .. } => break Region::Static,
 
                 Scope::Body { .. } | Scope::ObjectLifetimeDefault { lifetime: None, .. } => return,
 
@@ -1780,7 +1668,7 @@ fn is_late_bound_map(tcx: TyCtxt<'_>, def_id: LocalDefId) -> Option<&FxIndexSet<
 
     let mut late_bound = FxIndexSet::default();
 
-    let mut constrained_by_input = ConstrainedCollector::default();
+    let mut constrained_by_input = ConstrainedCollector { regions: Default::default(), tcx };
     for arg_ty in decl.inputs {
         constrained_by_input.visit_ty(arg_ty);
     }
@@ -1833,12 +1721,65 @@ fn is_late_bound_map(tcx: TyCtxt<'_>, def_id: LocalDefId) -> Option<&FxIndexSet<
     debug!(?late_bound);
     return Some(tcx.arena.alloc(late_bound));
 
-    #[derive(Default)]
-    struct ConstrainedCollector {
+    /// Visits a `ty::Ty` collecting information about what generic parameters are constrained.
+    ///
+    /// The visitor does not operate on `hir::Ty` so that it can be called on the rhs of a `type Alias<...> = ...;`
+    /// which may live in a separate crate so there would not be any hir available. Instead we use the `type_of`
+    /// query to obtain a `ty::Ty` which will be present even in cross crate scenarios. It also naturally
+    /// handles cycle detection as we go through the query system.
+    ///
+    /// This is necessary in the first place for the following case:
+    /// ```
+    /// type Alias<'a, T> = <T as Trait<'a>>::Assoc;
+    /// fn foo<'a>(_: Alias<'a, ()>) -> Alias<'a, ()> { ... }
+    /// ```
+    ///
+    /// If we conservatively considered `'a` unconstrained then we could break users who had written code before
+    /// we started correctly handling aliases. If we considered `'a` constrained then it would become late bound
+    /// causing an error during astconv as the `'a` is not constrained by the input type `<() as Trait<'a>>::Assoc`
+    /// but appears in the output type `<() as Trait<'a>>::Assoc`.
+    ///
+    /// We must therefore "look into" the `Alias` to see whether we should consider `'a` constrained or not.
+    ///
+    /// See #100508 #85533 #47511 for additional context
+    struct ConstrainedCollectorPostAstConv {
+        arg_is_constrained: Box<[bool]>,
+    }
+
+    use std::ops::ControlFlow;
+    use ty::Ty;
+    impl<'tcx> TypeVisitor<'tcx> for ConstrainedCollectorPostAstConv {
+        fn visit_ty(&mut self, t: Ty<'tcx>) -> ControlFlow<!> {
+            match t.kind() {
+                ty::Param(param_ty) => {
+                    self.arg_is_constrained[param_ty.index as usize] = true;
+                }
+                ty::Projection(_) => return ControlFlow::Continue(()),
+                _ => (),
+            }
+            t.super_visit_with(self)
+        }
+
+        fn visit_const(&mut self, _: ty::Const<'tcx>) -> ControlFlow<!> {
+            ControlFlow::Continue(())
+        }
+
+        fn visit_region(&mut self, r: ty::Region<'tcx>) -> ControlFlow<!> {
+            debug!("r={:?}", r.kind());
+            if let ty::RegionKind::ReEarlyBound(region) = r.kind() {
+                self.arg_is_constrained[region.index as usize] = true;
+            }
+
+            ControlFlow::Continue(())
+        }
+    }
+
+    struct ConstrainedCollector<'tcx> {
+        tcx: TyCtxt<'tcx>,
         regions: FxHashSet<LocalDefId>,
     }
 
-    impl<'v> Visitor<'v> for ConstrainedCollector {
+    impl<'v> Visitor<'v> for ConstrainedCollector<'_> {
         fn visit_ty(&mut self, ty: &'v hir::Ty<'v>) {
             match ty.kind {
                 hir::TyKind::Path(
@@ -1849,6 +1790,47 @@ fn is_late_bound_map(tcx: TyCtxt<'_>, def_id: LocalDefId) -> Option<&FxIndexSet<
                     // (defined above)
                 }
 
+                hir::TyKind::Path(hir::QPath::Resolved(
+                    None,
+                    hir::Path { res: Res::Def(DefKind::TyAlias, alias_def), segments, span },
+                )) => {
+                    // See comments on `ConstrainedCollectorPostAstConv` for why this arm does not just consider
+                    // substs to be unconstrained.
+                    let generics = self.tcx.generics_of(alias_def);
+                    let mut walker = ConstrainedCollectorPostAstConv {
+                        arg_is_constrained: vec![false; generics.params.len()].into_boxed_slice(),
+                    };
+                    walker.visit_ty(self.tcx.type_of(alias_def));
+
+                    match segments.last() {
+                        Some(hir::PathSegment { args: Some(args), .. }) => {
+                            let tcx = self.tcx;
+                            for constrained_arg in
+                                args.args.iter().enumerate().flat_map(|(n, arg)| {
+                                    match walker.arg_is_constrained.get(n) {
+                                        Some(true) => Some(arg),
+                                        Some(false) => None,
+                                        None => {
+                                            tcx.sess.delay_span_bug(
+                                                *span,
+                                                format!(
+                                                    "Incorrect generic arg count for alias {:?}",
+                                                    alias_def
+                                                ),
+                                            );
+                                            None
+                                        }
+                                    }
+                                })
+                            {
+                                self.visit_generic_arg(constrained_arg);
+                            }
+                        }
+                        Some(_) => (),
+                        None => bug!("Path with no segments or self type"),
+                    }
+                }
+
                 hir::TyKind::Path(hir::QPath::Resolved(None, ref path)) => {
                     // consider only the lifetimes on the final
                     // segment; I am not sure it's even currently
diff --git a/compiler/rustc_hir_analysis/src/collect/predicates_of.rs b/compiler/rustc_hir_analysis/src/collect/predicates_of.rs
index 2e84e1d01600..5d1ca1cbd238 100644
--- a/compiler/rustc_hir_analysis/src/collect/predicates_of.rs
+++ b/compiler/rustc_hir_analysis/src/collect/predicates_of.rs
@@ -427,6 +427,8 @@ pub(super) fn explicit_predicates_of<'tcx>(
     } else {
         if matches!(def_kind, DefKind::AnonConst) && tcx.lazy_normalization() {
             let hir_id = tcx.hir().local_def_id_to_hir_id(def_id.expect_local());
+            let parent_def_id = tcx.hir().get_parent_item(hir_id);
+
             if tcx.hir().opt_const_param_default_param_hir_id(hir_id).is_some() {
                 // In `generics_of` we set the generics' parent to be our parent's parent which means that
                 // we lose out on the predicates of our actual parent if we dont return those predicates here.
@@ -439,8 +441,33 @@ pub(super) fn explicit_predicates_of<'tcx>(
                 //        parent of generics returned by `generics_of`
                 //
                 // In the above code we want the anon const to have predicates in its param env for `T: Trait`
-                let item_def_id = tcx.hir().get_parent_item(hir_id);
-                // In the above code example we would be calling `explicit_predicates_of(Foo)` here
+                // and we would be calling `explicit_predicates_of(Foo)` here
+                return tcx.explicit_predicates_of(parent_def_id);
+            }
+
+            let parent_def_kind = tcx.def_kind(parent_def_id);
+            if matches!(parent_def_kind, DefKind::OpaqueTy) {
+                // In `instantiate_identity` we inherit the predicates of our parent.
+                // However, opaque types do not have a parent (see `gather_explicit_predicates_of`), which means
+                // that we lose out on the predicates of our actual parent if we dont return those predicates here.
+                //
+                //
+                // fn foo<T: Trait>() -> impl Iterator<Output = Another<{ <T as Trait>::ASSOC }> > { todo!() }
+                //                                                        ^^^^^^^^^^^^^^^^^^^ the def id we are calling
+                //                                                                            explicit_predicates_of on
+                //
+                // In the above code we want the anon const to have predicates in its param env for `T: Trait`.
+                // However, the anon const cannot inherit predicates from its parent since it's opaque.
+                //
+                // To fix this, we call `explicit_predicates_of` directly on `foo`, the parent's parent.
+
+                // In the above example this is `foo::{opaque#0}` or `impl Iterator`
+                let parent_hir_id = tcx.hir().local_def_id_to_hir_id(parent_def_id.def_id);
+
+                // In the above example this is the function `foo`
+                let item_def_id = tcx.hir().get_parent_item(parent_hir_id);
+
+                // In the above code example we would be calling `explicit_predicates_of(foo)` here
                 return tcx.explicit_predicates_of(item_def_id);
             }
         }
diff --git a/compiler/rustc_hir_analysis/src/collect/type_of.rs b/compiler/rustc_hir_analysis/src/collect/type_of.rs
index 32f359a81581..2402495c2e4a 100644
--- a/compiler/rustc_hir_analysis/src/collect/type_of.rs
+++ b/compiler/rustc_hir_analysis/src/collect/type_of.rs
@@ -319,7 +319,15 @@ pub(super) fn type_of(tcx: TyCtxt<'_>, def_id: DefId) -> Ty<'_> {
                     }
                 }
                 ItemKind::TyAlias(self_ty, _) => icx.to_ty(self_ty),
-                ItemKind::Impl(hir::Impl { self_ty, .. }) => icx.to_ty(*self_ty),
+                ItemKind::Impl(hir::Impl { self_ty, .. }) => {
+                    match self_ty.find_self_aliases() {
+                        spans if spans.len() > 0 => {
+                            tcx.sess.emit_err(crate::errors::SelfInImplSelf { span: spans.into(), note: (), });
+                            tcx.ty_error()
+                        },
+                        _ => icx.to_ty(*self_ty),
+                    }
+                },
                 ItemKind::Fn(..) => {
                     let substs = InternalSubsts::identity_for_item(tcx, def_id.to_def_id());
                     tcx.mk_fn_def(def_id.to_def_id(), substs)
@@ -635,24 +643,24 @@ fn find_opaque_ty_constraints_for_tait(tcx: TyCtxt<'_>, def_id: LocalDefId) -> T
             intravisit::walk_expr(self, ex);
         }
         fn visit_item(&mut self, it: &'tcx Item<'tcx>) {
-            trace!(?it.def_id);
+            trace!(?it.owner_id);
             // The opaque type itself or its children are not within its reveal scope.
-            if it.def_id.def_id != self.def_id {
-                self.check(it.def_id.def_id);
+            if it.owner_id.def_id != self.def_id {
+                self.check(it.owner_id.def_id);
                 intravisit::walk_item(self, it);
             }
         }
         fn visit_impl_item(&mut self, it: &'tcx ImplItem<'tcx>) {
-            trace!(?it.def_id);
+            trace!(?it.owner_id);
             // The opaque type itself or its children are not within its reveal scope.
-            if it.def_id.def_id != self.def_id {
-                self.check(it.def_id.def_id);
+            if it.owner_id.def_id != self.def_id {
+                self.check(it.owner_id.def_id);
                 intravisit::walk_impl_item(self, it);
             }
         }
         fn visit_trait_item(&mut self, it: &'tcx TraitItem<'tcx>) {
-            trace!(?it.def_id);
-            self.check(it.def_id.def_id);
+            trace!(?it.owner_id);
+            self.check(it.owner_id.def_id);
             intravisit::walk_trait_item(self, it);
         }
     }
@@ -690,11 +698,17 @@ fn find_opaque_ty_constraints_for_tait(tcx: TyCtxt<'_>, def_id: LocalDefId) -> T
     }
 
     let Some(hidden) = locator.found else {
-        tcx.sess.emit_err(UnconstrainedOpaqueType {
+        let reported = tcx.sess.emit_err(UnconstrainedOpaqueType {
             span: tcx.def_span(def_id),
             name: tcx.item_name(tcx.local_parent(def_id).to_def_id()),
+            what: match tcx.hir().get(scope) {
+                _ if scope == hir::CRATE_HIR_ID => "module",
+                Node::Item(hir::Item { kind: hir::ItemKind::Mod(_), .. }) => "module",
+                Node::Item(hir::Item { kind: hir::ItemKind::Impl(_), .. }) => "impl",
+                _ => "item",
+            },
         });
-        return tcx.ty_error();
+        return tcx.ty_error_with_guaranteed(reported);
     };
 
     // Only check against typeck if we didn't already error
@@ -764,24 +778,24 @@ fn find_opaque_ty_constraints_for_rpit(
             intravisit::walk_expr(self, ex);
         }
         fn visit_item(&mut self, it: &'tcx Item<'tcx>) {
-            trace!(?it.def_id);
+            trace!(?it.owner_id);
             // The opaque type itself or its children are not within its reveal scope.
-            if it.def_id.def_id != self.def_id {
-                self.check(it.def_id.def_id);
+            if it.owner_id.def_id != self.def_id {
+                self.check(it.owner_id.def_id);
                 intravisit::walk_item(self, it);
             }
         }
         fn visit_impl_item(&mut self, it: &'tcx ImplItem<'tcx>) {
-            trace!(?it.def_id);
+            trace!(?it.owner_id);
             // The opaque type itself or its children are not within its reveal scope.
-            if it.def_id.def_id != self.def_id {
-                self.check(it.def_id.def_id);
+            if it.owner_id.def_id != self.def_id {
+                self.check(it.owner_id.def_id);
                 intravisit::walk_impl_item(self, it);
             }
         }
         fn visit_trait_item(&mut self, it: &'tcx TraitItem<'tcx>) {
-            trace!(?it.def_id);
-            self.check(it.def_id.def_id);
+            trace!(?it.owner_id);
+            self.check(it.owner_id.def_id);
             intravisit::walk_trait_item(self, it);
         }
     }
diff --git a/compiler/rustc_hir_analysis/src/errors.rs b/compiler/rustc_hir_analysis/src/errors.rs
index 9457da32ce65..afbb27155a2f 100644
--- a/compiler/rustc_hir_analysis/src/errors.rs
+++ b/compiler/rustc_hir_analysis/src/errors.rs
@@ -1,7 +1,7 @@
 //! Errors emitted by `rustc_hir_analysis`.
 
-use rustc_errors::IntoDiagnostic;
 use rustc_errors::{error_code, Applicability, DiagnosticBuilder, ErrorGuaranteed, Handler};
+use rustc_errors::{IntoDiagnostic, MultiSpan};
 use rustc_macros::{Diagnostic, LintDiagnostic};
 use rustc_middle::ty::Ty;
 use rustc_span::{symbol::Ident, Span, Symbol};
@@ -120,7 +120,7 @@ pub struct TypeofReservedKeywordUsed<'tcx> {
     #[primary_span]
     #[label]
     pub span: Span,
-    #[suggestion_verbose(code = "{ty}")]
+    #[suggestion(style = "verbose", code = "{ty}")]
     pub opt_sugg: Option<(Span, Applicability)>,
 }
 
@@ -143,6 +143,7 @@ pub struct UnconstrainedOpaqueType {
     #[primary_span]
     pub span: Span,
     pub name: Symbol,
+    pub what: &'static str,
 }
 
 pub struct MissingTypeParams {
@@ -155,6 +156,7 @@ pub struct MissingTypeParams {
 
 // Manual implementation of `IntoDiagnostic` to be able to call `span_to_snippet`.
 impl<'a> IntoDiagnostic<'a> for MissingTypeParams {
+    #[track_caller]
     fn into_diagnostic(self, handler: &'a Handler) -> DiagnosticBuilder<'a, ErrorGuaranteed> {
         let mut err = handler.struct_span_err_with_code(
             self.span,
@@ -237,7 +239,11 @@ pub struct UnusedExternCrate {
 #[derive(LintDiagnostic)]
 #[diag(hir_analysis_extern_crate_not_idiomatic)]
 pub struct ExternCrateNotIdiomatic {
-    #[suggestion_short(applicability = "machine-applicable", code = "{suggestion_code}")]
+    #[suggestion(
+        style = "short",
+        applicability = "machine-applicable",
+        code = "{suggestion_code}"
+    )]
     pub span: Span,
     pub msg_code: String,
     pub suggestion_code: String,
@@ -249,3 +255,33 @@ pub struct ExpectedUsedSymbol {
     #[primary_span]
     pub span: Span,
 }
+
+#[derive(Diagnostic)]
+#[diag(hir_analysis_const_impl_for_non_const_trait)]
+pub struct ConstImplForNonConstTrait {
+    #[primary_span]
+    pub trait_ref_span: Span,
+    pub trait_name: String,
+    #[suggestion(applicability = "machine-applicable", code = "#[const_trait]")]
+    pub local_trait_span: Option<Span>,
+    #[note]
+    pub marking: (),
+    #[note(adding)]
+    pub adding: (),
+}
+
+#[derive(Diagnostic)]
+#[diag(hir_analysis_const_bound_for_non_const_trait)]
+pub struct ConstBoundForNonConstTrait {
+    #[primary_span]
+    pub span: Span,
+}
+
+#[derive(Diagnostic)]
+#[diag(hir_analysis_self_in_impl_self)]
+pub struct SelfInImplSelf {
+    #[primary_span]
+    pub span: MultiSpan,
+    #[note]
+    pub note: (),
+}
diff --git a/compiler/rustc_hir_analysis/src/impl_wf_check.rs b/compiler/rustc_hir_analysis/src/impl_wf_check.rs
index a84257b939c5..136f6199911a 100644
--- a/compiler/rustc_hir_analysis/src/impl_wf_check.rs
+++ b/compiler/rustc_hir_analysis/src/impl_wf_check.rs
@@ -55,10 +55,10 @@ fn check_mod_impl_wf(tcx: TyCtxt<'_>, module_def_id: LocalDefId) {
     let min_specialization = tcx.features().min_specialization;
     let module = tcx.hir_module_items(module_def_id);
     for id in module.items() {
-        if matches!(tcx.def_kind(id.def_id), DefKind::Impl) {
-            enforce_impl_params_are_constrained(tcx, id.def_id.def_id);
+        if matches!(tcx.def_kind(id.owner_id), DefKind::Impl) {
+            enforce_impl_params_are_constrained(tcx, id.owner_id.def_id);
             if min_specialization {
-                check_min_specialization(tcx, id.def_id.def_id);
+                check_min_specialization(tcx, id.owner_id.def_id);
             }
         }
     }
diff --git a/compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs b/compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs
index e806e94879d9..55cca0cd2d7b 100644
--- a/compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs
+++ b/compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs
@@ -69,6 +69,7 @@ use crate::constrained_generic_params as cgp;
 use crate::errors::SubstsOnOverriddenImpl;
 
 use rustc_data_structures::fx::FxHashSet;
+use rustc_hir as hir;
 use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_infer::infer::outlives::env::OutlivesEnvironment;
 use rustc_infer::infer::TyCtxtInferExt;
@@ -80,6 +81,7 @@ use rustc_span::Span;
 use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt;
 use rustc_trait_selection::traits::outlives_bounds::InferCtxtExt as _;
 use rustc_trait_selection::traits::{self, translate_substs, wf, ObligationCtxt};
+use tracing::instrument;
 
 pub(super) fn check_min_specialization(tcx: TyCtxt<'_>, impl_def_id: LocalDefId) {
     if let Some(node) = parent_specialization_node(tcx, impl_def_id) {
@@ -103,13 +105,11 @@ fn parent_specialization_node(tcx: TyCtxt<'_>, impl1_def_id: LocalDefId) -> Opti
 }
 
 /// Check that `impl1` is a sound specialization
+#[instrument(level = "debug", skip(tcx))]
 fn check_always_applicable(tcx: TyCtxt<'_>, impl1_def_id: LocalDefId, impl2_node: Node) {
     if let Some((impl1_substs, impl2_substs)) = get_impl_substs(tcx, impl1_def_id, impl2_node) {
         let impl2_def_id = impl2_node.def_id();
-        debug!(
-            "check_always_applicable(\nimpl1_def_id={:?},\nimpl2_def_id={:?},\nimpl2_substs={:?}\n)",
-            impl1_def_id, impl2_def_id, impl2_substs
-        );
+        debug!(?impl2_def_id, ?impl2_substs);
 
         let parent_substs = if impl2_node.is_from_trait() {
             impl2_substs.to_vec()
@@ -118,12 +118,33 @@ fn check_always_applicable(tcx: TyCtxt<'_>, impl1_def_id: LocalDefId, impl2_node
         };
 
         let span = tcx.def_span(impl1_def_id);
+        check_constness(tcx, impl1_def_id, impl2_node, span);
         check_static_lifetimes(tcx, &parent_substs, span);
         check_duplicate_params(tcx, impl1_substs, &parent_substs, span);
         check_predicates(tcx, impl1_def_id, impl1_substs, impl2_node, impl2_substs, span);
     }
 }
 
+/// Check that the specializing impl `impl1` is at least as const as the base
+/// impl `impl2`
+fn check_constness(tcx: TyCtxt<'_>, impl1_def_id: LocalDefId, impl2_node: Node, span: Span) {
+    if impl2_node.is_from_trait() {
+        // This isn't a specialization
+        return;
+    }
+
+    let impl1_constness = tcx.constness(impl1_def_id.to_def_id());
+    let impl2_constness = tcx.constness(impl2_node.def_id());
+
+    if let hir::Constness::Const = impl2_constness {
+        if let hir::Constness::NotConst = impl1_constness {
+            tcx.sess
+                .struct_span_err(span, "cannot specialize on const impl with non-const impl")
+                .emit();
+        }
+    }
+}
+
 /// Given a specializing impl `impl1`, and the base impl `impl2`, returns two
 /// substitutions `(S1, S2)` that equate their trait references. The returned
 /// types are expressed in terms of the generics of `impl1`.
@@ -155,7 +176,7 @@ fn get_impl_substs<'tcx>(
 
     let errors = ocx.select_all_or_error();
     if !errors.is_empty() {
-        ocx.infcx.err_ctxt().report_fulfillment_errors(&errors, None, false);
+        ocx.infcx.err_ctxt().report_fulfillment_errors(&errors, None);
         return None;
     }
 
@@ -278,15 +299,15 @@ fn check_static_lifetimes<'tcx>(
 
 /// Check whether predicates on the specializing impl (`impl1`) are allowed.
 ///
-/// Each predicate `P` must be:
+/// Each predicate `P` must be one of:
 ///
-/// * global (not reference any parameters)
-/// * `T: Tr` predicate where `Tr` is an always-applicable trait
-/// * on the base `impl impl2`
-///     * Currently this check is done using syntactic equality, which is
-///       conservative but generally sufficient.
-/// * a well-formed predicate of a type argument of the trait being implemented,
+/// * Global (not reference any parameters).
+/// * A `T: Tr` predicate where `Tr` is an always-applicable trait.
+/// * Present on the base impl `impl2`.
+///     * This check is done using the `trait_predicates_eq` function below.
+/// * A well-formed predicate of a type argument of the trait being implemented,
 ///   including the `Self`-type.
+#[instrument(level = "debug", skip(tcx))]
 fn check_predicates<'tcx>(
     tcx: TyCtxt<'tcx>,
     impl1_def_id: LocalDefId,
@@ -322,10 +343,7 @@ fn check_predicates<'tcx>(
         .map(|obligation| obligation.predicate)
         .collect()
     };
-    debug!(
-        "check_always_applicable(\nimpl1_predicates={:?},\nimpl2_predicates={:?}\n)",
-        impl1_predicates, impl2_predicates,
-    );
+    debug!(?impl1_predicates, ?impl2_predicates);
 
     // Since impls of always applicable traits don't get to assume anything, we
     // can also assume their supertraits apply.
@@ -373,25 +391,83 @@ fn check_predicates<'tcx>(
     );
 
     for (predicate, span) in impl1_predicates {
-        if !impl2_predicates.contains(&predicate) {
+        if !impl2_predicates.iter().any(|pred2| trait_predicates_eq(tcx, predicate, *pred2, span)) {
             check_specialization_on(tcx, predicate, span)
         }
     }
 }
 
+/// Checks if some predicate on the specializing impl (`predicate1`) is the same
+/// as some predicate on the base impl (`predicate2`).
+///
+/// This basically just checks syntactic equivalence, but is a little more
+/// forgiving since we want to equate `T: Tr` with `T: ~const Tr` so this can work:
+///
+/// ```ignore (illustrative)
+/// #[rustc_specialization_trait]
+/// trait Specialize { }
+///
+/// impl<T: Bound> Tr for T { }
+/// impl<T: ~const Bound + Specialize> const Tr for T { }
+/// ```
+///
+/// However, we *don't* want to allow the reverse, i.e., when the bound on the
+/// specializing impl is not as const as the bound on the base impl:
+///
+/// ```ignore (illustrative)
+/// impl<T: ~const Bound> const Tr for T { }
+/// impl<T: Bound + Specialize> const Tr for T { } // should be T: ~const Bound
+/// ```
+///
+/// So we make that check in this function and try to raise a helpful error message.
+fn trait_predicates_eq<'tcx>(
+    tcx: TyCtxt<'tcx>,
+    predicate1: ty::Predicate<'tcx>,
+    predicate2: ty::Predicate<'tcx>,
+    span: Span,
+) -> bool {
+    let pred1_kind = predicate1.kind().skip_binder();
+    let pred2_kind = predicate2.kind().skip_binder();
+    let (trait_pred1, trait_pred2) = match (pred1_kind, pred2_kind) {
+        (ty::PredicateKind::Trait(pred1), ty::PredicateKind::Trait(pred2)) => (pred1, pred2),
+        // Just use plain syntactic equivalence if either of the predicates aren't
+        // trait predicates or have bound vars.
+        _ => return predicate1 == predicate2,
+    };
+
+    let predicates_equal_modulo_constness = {
+        let pred1_unconsted =
+            ty::TraitPredicate { constness: ty::BoundConstness::NotConst, ..trait_pred1 };
+        let pred2_unconsted =
+            ty::TraitPredicate { constness: ty::BoundConstness::NotConst, ..trait_pred2 };
+        pred1_unconsted == pred2_unconsted
+    };
+
+    if !predicates_equal_modulo_constness {
+        return false;
+    }
+
+    // Check that the predicate on the specializing impl is at least as const as
+    // the one on the base.
+    match (trait_pred2.constness, trait_pred1.constness) {
+        (ty::BoundConstness::ConstIfConst, ty::BoundConstness::NotConst) => {
+            tcx.sess.struct_span_err(span, "missing `~const` qualifier for specialization").emit();
+        }
+        _ => {}
+    }
+
+    true
+}
+
+#[instrument(level = "debug", skip(tcx))]
 fn check_specialization_on<'tcx>(tcx: TyCtxt<'tcx>, predicate: ty::Predicate<'tcx>, span: Span) {
-    debug!("can_specialize_on(predicate = {:?})", predicate);
     match predicate.kind().skip_binder() {
         // Global predicates are either always true or always false, so we
         // are fine to specialize on.
         _ if predicate.is_global() => (),
         // We allow specializing on explicitly marked traits with no associated
         // items.
-        ty::PredicateKind::Trait(ty::TraitPredicate {
-            trait_ref,
-            constness: ty::BoundConstness::NotConst,
-            polarity: _,
-        }) => {
+        ty::PredicateKind::Trait(ty::TraitPredicate { trait_ref, constness: _, polarity: _ }) => {
             if !matches!(
                 trait_predicate_kind(tcx, predicate),
                 Some(TraitSpecializationKind::Marker)
diff --git a/compiler/rustc_hir_analysis/src/lib.rs b/compiler/rustc_hir_analysis/src/lib.rs
index dba505149de8..664d3a3a1db8 100644
--- a/compiler/rustc_hir_analysis/src/lib.rs
+++ b/compiler/rustc_hir_analysis/src/lib.rs
@@ -106,7 +106,7 @@ use rustc_middle::middle;
 use rustc_middle::ty::query::Providers;
 use rustc_middle::ty::{self, Ty, TyCtxt};
 use rustc_middle::util;
-use rustc_session::config::EntryFnType;
+use rustc_session::{config::EntryFnType, parse::feature_err};
 use rustc_span::{symbol::sym, Span, DUMMY_SP};
 use rustc_target::spec::abi::Abi;
 use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt as _;
@@ -118,20 +118,40 @@ use astconv::AstConv;
 use bounds::Bounds;
 
 fn require_c_abi_if_c_variadic(tcx: TyCtxt<'_>, decl: &hir::FnDecl<'_>, abi: Abi, span: Span) {
-    match (decl.c_variadic, abi) {
-        // The function has the correct calling convention, or isn't a "C-variadic" function.
-        (false, _) | (true, Abi::C { .. }) | (true, Abi::Cdecl { .. }) => {}
-        // The function is a "C-variadic" function with an incorrect calling convention.
-        (true, _) => {
-            let mut err = struct_span_err!(
-                tcx.sess,
-                span,
-                E0045,
-                "C-variadic function must have C or cdecl calling convention"
-            );
-            err.span_label(span, "C-variadics require C or cdecl calling convention").emit();
-        }
+    const ERROR_HEAD: &str = "C-variadic function must have a compatible calling convention";
+    const CONVENTIONS_UNSTABLE: &str = "`C`, `cdecl`, `win64`, `sysv64` or `efiapi`";
+    const CONVENTIONS_STABLE: &str = "`C` or `cdecl`";
+    const UNSTABLE_EXPLAIN: &str =
+        "using calling conventions other than `C` or `cdecl` for varargs functions is unstable";
+
+    if !decl.c_variadic || matches!(abi, Abi::C { .. } | Abi::Cdecl { .. }) {
+        return;
     }
+
+    let extended_abi_support = tcx.features().extended_varargs_abi_support;
+    let conventions = match (extended_abi_support, abi.supports_varargs()) {
+        // User enabled additional ABI support for varargs and function ABI matches those ones.
+        (true, true) => return,
+
+        // Using this ABI would be ok, if the feature for additional ABI support was enabled.
+        // Return CONVENTIONS_STABLE, because we want the other error to look the same.
+        (false, true) => {
+            feature_err(
+                &tcx.sess.parse_sess,
+                sym::extended_varargs_abi_support,
+                span,
+                UNSTABLE_EXPLAIN,
+            )
+            .emit();
+            CONVENTIONS_STABLE
+        }
+
+        (false, false) => CONVENTIONS_STABLE,
+        (true, false) => CONVENTIONS_UNSTABLE,
+    };
+
+    let mut err = struct_span_err!(tcx.sess, span, E0045, "{}, like {}", ERROR_HEAD, conventions);
+    err.span_label(span, ERROR_HEAD).emit();
 }
 
 fn require_same_types<'tcx>(
@@ -153,7 +173,7 @@ fn require_same_types<'tcx>(
     match &errors[..] {
         [] => true,
         errors => {
-            infcx.err_ctxt().report_fulfillment_errors(errors, None, false);
+            infcx.err_ctxt().report_fulfillment_errors(errors, None);
             false
         }
     }
@@ -316,7 +336,7 @@ fn check_main_fn_ty(tcx: TyCtxt<'_>, main_def_id: DefId) {
         ocx.register_bound(cause, param_env, norm_return_ty, term_did);
         let errors = ocx.select_all_or_error();
         if !errors.is_empty() {
-            infcx.err_ctxt().report_fulfillment_errors(&errors, None, false);
+            infcx.err_ctxt().report_fulfillment_errors(&errors, None);
             error = true;
         }
         // now we can take the return type of the given main function
@@ -381,7 +401,7 @@ fn check_start_fn_ty(tcx: TyCtxt<'_>, start_def_id: DefId) {
                         error = true;
                     }
                     if let hir::IsAsync::Async = sig.header.asyncness {
-                        let span = tcx.def_span(it.def_id);
+                        let span = tcx.def_span(it.owner_id);
                         struct_span_err!(
                             tcx.sess,
                             span,
diff --git a/compiler/rustc_hir_analysis/src/outlives/implicit_infer.rs b/compiler/rustc_hir_analysis/src/outlives/implicit_infer.rs
index 064a70107fe8..90c6edb65e46 100644
--- a/compiler/rustc_hir_analysis/src/outlives/implicit_infer.rs
+++ b/compiler/rustc_hir_analysis/src/outlives/implicit_infer.rs
@@ -29,7 +29,7 @@ pub(super) fn infer_predicates<'tcx>(
 
         // Visit all the crates and infer predicates
         for id in tcx.hir().items() {
-            let item_did = id.def_id;
+            let item_did = id.owner_id;
 
             debug!("InferVisitor::visit_item(item={:?})", item_did);
 
diff --git a/compiler/rustc_hir_analysis/src/outlives/test.rs b/compiler/rustc_hir_analysis/src/outlives/test.rs
index eb0e1203405c..fa2ac56593bc 100644
--- a/compiler/rustc_hir_analysis/src/outlives/test.rs
+++ b/compiler/rustc_hir_analysis/src/outlives/test.rs
@@ -6,11 +6,11 @@ pub fn test_inferred_outlives(tcx: TyCtxt<'_>) {
     for id in tcx.hir().items() {
         // For unit testing: check for a special "rustc_outlives"
         // attribute and report an error with various results if found.
-        if tcx.has_attr(id.def_id.to_def_id(), sym::rustc_outlives) {
-            let inferred_outlives_of = tcx.inferred_outlives_of(id.def_id);
+        if tcx.has_attr(id.owner_id.to_def_id(), sym::rustc_outlives) {
+            let inferred_outlives_of = tcx.inferred_outlives_of(id.owner_id);
             struct_span_err!(
                 tcx.sess,
-                tcx.def_span(id.def_id),
+                tcx.def_span(id.owner_id),
                 E0640,
                 "{:?}",
                 inferred_outlives_of
diff --git a/compiler/rustc_hir_analysis/src/variance/test.rs b/compiler/rustc_hir_analysis/src/variance/test.rs
index 2ba87db880b4..83ed3e44b3d7 100644
--- a/compiler/rustc_hir_analysis/src/variance/test.rs
+++ b/compiler/rustc_hir_analysis/src/variance/test.rs
@@ -6,9 +6,10 @@ pub fn test_variance(tcx: TyCtxt<'_>) {
     // For unit testing: check for a special "rustc_variance"
     // attribute and report an error with various results if found.
     for id in tcx.hir().items() {
-        if tcx.has_attr(id.def_id.to_def_id(), sym::rustc_variance) {
-            let variances_of = tcx.variances_of(id.def_id);
-            struct_span_err!(tcx.sess, tcx.def_span(id.def_id), E0208, "{:?}", variances_of).emit();
+        if tcx.has_attr(id.owner_id.to_def_id(), sym::rustc_variance) {
+            let variances_of = tcx.variances_of(id.owner_id);
+            struct_span_err!(tcx.sess, tcx.def_span(id.owner_id), E0208, "{:?}", variances_of)
+                .emit();
         }
     }
 }
diff --git a/compiler/rustc_hir_typeck/src/_match.rs b/compiler/rustc_hir_typeck/src/_match.rs
index 2b15d4dcd084..6a4a6a5b0a54 100644
--- a/compiler/rustc_hir_typeck/src/_match.rs
+++ b/compiler/rustc_hir_typeck/src/_match.rs
@@ -1,6 +1,6 @@
 use crate::coercion::{AsCoercionSite, CoerceMany};
 use crate::{Diverges, Expectation, FnCtxt, Needs};
-use rustc_errors::{Applicability, MultiSpan};
+use rustc_errors::{Applicability, Diagnostic, MultiSpan};
 use rustc_hir::{self as hir, ExprKind};
 use rustc_infer::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKind};
 use rustc_infer::traits::Obligation;
@@ -137,55 +137,13 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 Some(&arm.body),
                 arm_ty,
                 Some(&mut |err| {
-                    let Some(ret) = self
-                        .tcx
-                        .hir()
-                        .find_by_def_id(self.body_id.owner.def_id)
-                        .and_then(|owner| owner.fn_decl())
-                        .map(|decl| decl.output.span())
-                    else { return; };
-                    let Expectation::IsLast(stmt) = orig_expected else {
-                        return
-                    };
-                    let can_coerce_to_return_ty = match self.ret_coercion.as_ref() {
-                        Some(ret_coercion) if self.in_tail_expr => {
-                            let ret_ty = ret_coercion.borrow().expected_ty();
-                            let ret_ty = self.inh.infcx.shallow_resolve(ret_ty);
-                            self.can_coerce(arm_ty, ret_ty)
-                                && prior_arm.map_or(true, |(_, t, _)| self.can_coerce(t, ret_ty))
-                                // The match arms need to unify for the case of `impl Trait`.
-                                && !matches!(ret_ty.kind(), ty::Opaque(..))
-                        }
-                        _ => false,
-                    };
-                    if !can_coerce_to_return_ty {
-                        return;
-                    }
-
-                    let semi_span = expr.span.shrink_to_hi().with_hi(stmt.hi());
-                    let mut ret_span: MultiSpan = semi_span.into();
-                    ret_span.push_span_label(
-                        expr.span,
-                        "this could be implicitly returned but it is a statement, not a \
-                            tail expression",
-                    );
-                    ret_span
-                        .push_span_label(ret, "the `match` arms can conform to this return type");
-                    ret_span.push_span_label(
-                        semi_span,
-                        "the `match` is a statement because of this semicolon, consider \
-                            removing it",
-                    );
-                    err.span_note(
-                        ret_span,
-                        "you might have meant to return the `match` expression",
-                    );
-                    err.tool_only_span_suggestion(
-                        semi_span,
-                        "remove this semicolon",
-                        "",
-                        Applicability::MaybeIncorrect,
-                    );
+                    self.suggest_removing_semicolon_for_coerce(
+                        err,
+                        expr,
+                        orig_expected,
+                        arm_ty,
+                        prior_arm,
+                    )
                 }),
                 false,
             );
@@ -219,6 +177,71 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         coercion.complete(self)
     }
 
+    fn suggest_removing_semicolon_for_coerce(
+        &self,
+        diag: &mut Diagnostic,
+        expr: &hir::Expr<'tcx>,
+        expectation: Expectation<'tcx>,
+        arm_ty: Ty<'tcx>,
+        prior_arm: Option<(Option<hir::HirId>, Ty<'tcx>, Span)>,
+    ) {
+        let hir = self.tcx.hir();
+
+        // First, check that we're actually in the tail of a function.
+        let hir::Node::Expr(hir::Expr { kind: hir::ExprKind::Block(block, _), .. }) =
+            hir.get(self.body_id) else { return; };
+        let Some(hir::Stmt { kind: hir::StmtKind::Semi(last_expr), .. })
+            = block.innermost_block().stmts.last() else {  return; };
+        if last_expr.hir_id != expr.hir_id {
+            return;
+        }
+
+        // Next, make sure that we have no type expectation.
+        let Some(ret) = hir
+            .find_by_def_id(self.body_id.owner.def_id)
+            .and_then(|owner| owner.fn_decl())
+            .map(|decl| decl.output.span()) else { return; };
+        let Expectation::IsLast(stmt) = expectation else {
+            return;
+        };
+
+        let can_coerce_to_return_ty = match self.ret_coercion.as_ref() {
+            Some(ret_coercion) => {
+                let ret_ty = ret_coercion.borrow().expected_ty();
+                let ret_ty = self.inh.infcx.shallow_resolve(ret_ty);
+                self.can_coerce(arm_ty, ret_ty)
+                    && prior_arm.map_or(true, |(_, ty, _)| self.can_coerce(ty, ret_ty))
+                    // The match arms need to unify for the case of `impl Trait`.
+                    && !matches!(ret_ty.kind(), ty::Opaque(..))
+            }
+            _ => false,
+        };
+        if !can_coerce_to_return_ty {
+            return;
+        }
+
+        let semi_span = expr.span.shrink_to_hi().with_hi(stmt.hi());
+        let mut ret_span: MultiSpan = semi_span.into();
+        ret_span.push_span_label(
+            expr.span,
+            "this could be implicitly returned but it is a statement, not a \
+                            tail expression",
+        );
+        ret_span.push_span_label(ret, "the `match` arms can conform to this return type");
+        ret_span.push_span_label(
+            semi_span,
+            "the `match` is a statement because of this semicolon, consider \
+                            removing it",
+        );
+        diag.span_note(ret_span, "you might have meant to return the `match` expression");
+        diag.tool_only_span_suggestion(
+            semi_span,
+            "remove this semicolon",
+            "",
+            Applicability::MaybeIncorrect,
+        );
+    }
+
     /// When the previously checked expression (the scrutinee) diverges,
     /// warn the user about the match arms being unreachable.
     fn warn_arms_when_scrutinee_diverges(&self, arms: &'tcx [hir::Arm<'tcx>]) {
@@ -491,11 +514,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     ..
                 } = self.type_var_origin(expected)? else { return None; };
 
-                let sig = *self
-                    .typeck_results
-                    .borrow()
-                    .liberated_fn_sigs()
-                    .get(hir::HirId::make_owner(self.body_id.owner.def_id))?;
+                let sig = self.body_fn_sig()?;
 
                 let substs = sig.output().walk().find_map(|arg| {
                     if let ty::GenericArgKind::Type(ty) = arg.unpack()
diff --git a/compiler/rustc_hir_typeck/src/autoderef.rs b/compiler/rustc_hir_typeck/src/autoderef.rs
index 59c366ad7d77..41b52a4c4a9f 100644
--- a/compiler/rustc_hir_typeck/src/autoderef.rs
+++ b/compiler/rustc_hir_typeck/src/autoderef.rs
@@ -12,18 +12,7 @@ use std::iter;
 
 impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     pub fn autoderef(&'a self, span: Span, base_ty: Ty<'tcx>) -> Autoderef<'a, 'tcx> {
-        Autoderef::new(self, self.param_env, self.body_id, span, base_ty, span)
-    }
-
-    /// Like `autoderef`, but provides a custom `Span` to use for calls to
-    /// an overloaded `Deref` operator
-    pub fn autoderef_overloaded_span(
-        &'a self,
-        span: Span,
-        base_ty: Ty<'tcx>,
-        overloaded_span: Span,
-    ) -> Autoderef<'a, 'tcx> {
-        Autoderef::new(self, self.param_env, self.body_id, span, base_ty, overloaded_span)
+        Autoderef::new(self, self.param_env, self.body_id, span, base_ty)
     }
 
     pub fn try_overloaded_deref(
@@ -55,11 +44,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         |InferOk { value: method, obligations: o }| {
                             obligations.extend(o);
                             if let ty::Ref(region, _, mutbl) = *method.sig.output().kind() {
-                                Some(OverloadedDeref {
-                                    region,
-                                    mutbl,
-                                    span: autoderef.overloaded_span(),
-                                })
+                                Some(OverloadedDeref { region, mutbl, span: autoderef.span() })
                             } else {
                                 None
                             }
diff --git a/compiler/rustc_hir_typeck/src/callee.rs b/compiler/rustc_hir_typeck/src/callee.rs
index 1b33f2f02b8a..2b019c8c9b7a 100644
--- a/compiler/rustc_hir_typeck/src/callee.rs
+++ b/compiler/rustc_hir_typeck/src/callee.rs
@@ -129,6 +129,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         output
     }
 
+    #[instrument(level = "debug", skip(self, call_expr, callee_expr, arg_exprs, autoderef), ret)]
     fn try_overloaded_call_step(
         &self,
         call_expr: &'tcx hir::Expr<'tcx>,
@@ -138,10 +139,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     ) -> Option<CallStep<'tcx>> {
         let adjusted_ty =
             self.structurally_resolved_type(autoderef.span(), autoderef.final_ty(false));
-        debug!(
-            "try_overloaded_call_step(call_expr={:?}, adjusted_ty={:?})",
-            call_expr, adjusted_ty
-        );
 
         // If the callee is a bare function or a closure, then we're all set.
         match *adjusted_ty.kind() {
@@ -471,6 +468,22 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             def_id,
         );
 
+        if fn_sig.abi == abi::Abi::RustCall {
+            let sp = arg_exprs.last().map_or(call_expr.span, |expr| expr.span);
+            if let Some(ty) = fn_sig.inputs().last().copied() {
+                self.register_bound(
+                    ty,
+                    self.tcx.require_lang_item(hir::LangItem::Tuple, Some(sp)),
+                    traits::ObligationCause::new(sp, self.body_id, traits::RustCall),
+                );
+            } else {
+                self.tcx.sess.span_err(
+                        sp,
+                        "functions with the \"rust-call\" ABI must take a single non-self tuple argument",
+                    );
+            }
+        }
+
         fn_sig.output()
     }
 
diff --git a/compiler/rustc_hir_typeck/src/cast.rs b/compiler/rustc_hir_typeck/src/cast.rs
index 0e7576ecf8b0..7d3129f7ea73 100644
--- a/compiler/rustc_hir_typeck/src/cast.rs
+++ b/compiler/rustc_hir_typeck/src/cast.rs
@@ -60,6 +60,8 @@ pub struct CastCheck<'tcx> {
     cast_ty: Ty<'tcx>,
     cast_span: Span,
     span: Span,
+    /// whether the cast is made in a const context or not.
+    pub constness: hir::Constness,
 }
 
 /// The kind of pointer and associated metadata (thin, length or vtable) - we
@@ -92,10 +94,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         debug!("pointer_kind({:?}, {:?})", t, span);
 
         let t = self.resolve_vars_if_possible(t);
-
-        if let Some(reported) = t.error_reported() {
-            return Err(reported);
-        }
+        t.error_reported()?;
 
         if self.type_is_sized_modulo_regions(self.param_env, t, span) {
             return Ok(Some(PointerKind::Thin));
@@ -210,17 +209,17 @@ impl<'a, 'tcx> CastCheck<'tcx> {
         cast_ty: Ty<'tcx>,
         cast_span: Span,
         span: Span,
+        constness: hir::Constness,
     ) -> Result<CastCheck<'tcx>, ErrorGuaranteed> {
         let expr_span = expr.span.find_ancestor_inside(span).unwrap_or(expr.span);
-        let check = CastCheck { expr, expr_ty, expr_span, cast_ty, cast_span, span };
+        let check = CastCheck { expr, expr_ty, expr_span, cast_ty, cast_span, span, constness };
 
         // For better error messages, check for some obviously unsized
         // cases now. We do a more thorough check at the end, once
         // inference is more completely known.
         match cast_ty.kind() {
             ty::Dynamic(_, _, ty::Dyn) | ty::Slice(..) => {
-                let reported = check.report_cast_to_unsized_type(fcx);
-                Err(reported)
+                Err(check.report_cast_to_unsized_type(fcx))
             }
             _ => Ok(check),
         }
@@ -611,10 +610,11 @@ impl<'a, 'tcx> CastCheck<'tcx> {
     }
 
     fn report_cast_to_unsized_type(&self, fcx: &FnCtxt<'a, 'tcx>) -> ErrorGuaranteed {
-        if let Some(reported) =
-            self.cast_ty.error_reported().or_else(|| self.expr_ty.error_reported())
-        {
-            return reported;
+        if let Err(err) = self.cast_ty.error_reported() {
+            return err;
+        }
+        if let Err(err) = self.expr_ty.error_reported() {
+            return err;
         }
 
         let tstr = fcx.ty_to_string(self.cast_ty);
@@ -866,7 +866,13 @@ impl<'a, 'tcx> CastCheck<'tcx> {
 
             (Int(_) | Float, Int(_) | Float) => Ok(CastKind::NumericCast),
 
-            (_, DynStar) | (DynStar, _) => bug!("should be handled by `try_coerce`"),
+            (_, DynStar) | (DynStar, _) => {
+                if fcx.tcx.features().dyn_star {
+                    bug!("should be handled by `try_coerce`")
+                } else {
+                    Err(CastError::IllegalCast)
+                }
+            }
         }
     }
 
diff --git a/compiler/rustc_hir_typeck/src/check.rs b/compiler/rustc_hir_typeck/src/check.rs
index 7f76364e15a7..3c57e33f6f7f 100644
--- a/compiler/rustc_hir_typeck/src/check.rs
+++ b/compiler/rustc_hir_typeck/src/check.rs
@@ -6,13 +6,11 @@ use rustc_hir as hir;
 use rustc_hir::def::DefKind;
 use rustc_hir::intravisit::Visitor;
 use rustc_hir::lang_items::LangItem;
-use rustc_hir::{ImplicitSelfKind, ItemKind, Node};
 use rustc_hir_analysis::check::fn_maybe_err;
 use rustc_infer::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKind};
 use rustc_infer::infer::RegionVariableOrigin;
 use rustc_middle::ty::{self, Ty, TyCtxt};
 use rustc_span::def_id::LocalDefId;
-use rustc_target::spec::abi::Abi;
 use rustc_trait_selection::traits;
 use std::cell::RefCell;
 
@@ -31,13 +29,11 @@ pub(super) fn check_fn<'a, 'tcx>(
     fn_id: hir::HirId,
     body: &'tcx hir::Body<'tcx>,
     can_be_generator: Option<hir::Movability>,
-    return_type_pre_known: bool,
 ) -> (FnCtxt<'a, 'tcx>, Option<GeneratorTypes<'tcx>>) {
     // Create the function context. This is either derived from scratch or,
     // in the case of closures, based on the outer context.
     let mut fcx = FnCtxt::new(inherited, param_env, body.value.hir_id);
     fcx.ps.set(UnsafetyState::function(fn_sig.unsafety, fn_id));
-    fcx.return_type_pre_known = return_type_pre_known;
 
     let tcx = fcx.tcx;
     let hir = tcx.hir();
@@ -51,9 +47,6 @@ pub(super) fn check_fn<'a, 'tcx>(
             decl.output.span(),
             param_env,
         ));
-    // If we replaced declared_ret_ty with infer vars, then we must be inferring
-    // an opaque type, so set a flag so we can improve diagnostics.
-    fcx.return_type_has_opaque = ret_ty != declared_ret_ty;
 
     fcx.ret_coercion = Some(RefCell::new(CoerceMany::new(ret_ty)));
 
@@ -61,41 +54,6 @@ pub(super) fn check_fn<'a, 'tcx>(
 
     fn_maybe_err(tcx, span, fn_sig.abi);
 
-    if fn_sig.abi == Abi::RustCall {
-        let expected_args = if let ImplicitSelfKind::None = decl.implicit_self { 1 } else { 2 };
-
-        let err = || {
-            let item = match tcx.hir().get(fn_id) {
-                Node::Item(hir::Item { kind: ItemKind::Fn(header, ..), .. }) => Some(header),
-                Node::ImplItem(hir::ImplItem {
-                    kind: hir::ImplItemKind::Fn(header, ..), ..
-                }) => Some(header),
-                Node::TraitItem(hir::TraitItem {
-                    kind: hir::TraitItemKind::Fn(header, ..),
-                    ..
-                }) => Some(header),
-                // Closures are RustCall, but they tuple their arguments, so shouldn't be checked
-                Node::Expr(hir::Expr { kind: hir::ExprKind::Closure { .. }, .. }) => None,
-                node => bug!("Item being checked wasn't a function/closure: {:?}", node),
-            };
-
-            if let Some(header) = item {
-                tcx.sess.span_err(header.span, "functions with the \"rust-call\" ABI must take a single non-self argument that is a tuple");
-            }
-        };
-
-        if fn_sig.inputs().len() != expected_args {
-            err()
-        } else {
-            // FIXME(CraftSpider) Add a check on parameter expansion, so we don't just make the ICE happen later on
-            //   This will probably require wide-scale changes to support a TupleKind obligation
-            //   We can't resolve this without knowing the type of the param
-            if !matches!(fn_sig.inputs()[expected_args - 1].kind(), ty::Tuple(_) | ty::Param(_)) {
-                err()
-            }
-        }
-    }
-
     if body.generator_kind.is_some() && can_be_generator.is_some() {
         let yield_ty = fcx
             .next_ty_var(TypeVariableOrigin { kind: TypeVariableOriginKind::TypeInference, span });
@@ -142,7 +100,6 @@ pub(super) fn check_fn<'a, 'tcx>(
 
     inherited.typeck_results.borrow_mut().liberated_fn_sigs_mut().insert(fn_id, fn_sig);
 
-    fcx.in_tail_expr = true;
     if let ty::Dynamic(..) = declared_ret_ty.kind() {
         // FIXME: We need to verify that the return type is `Sized` after the return expression has
         // been evaluated so that we have types available for all the nodes being returned, but that
@@ -161,7 +118,6 @@ pub(super) fn check_fn<'a, 'tcx>(
         fcx.require_type_is_sized(declared_ret_ty, decl.output.span(), traits::SizedReturnType);
         fcx.check_return_expr(&body.value, false);
     }
-    fcx.in_tail_expr = false;
 
     // We insert the deferred_generator_interiors entry after visiting the body.
     // This ensures that all nested generators appear before the entry of this generator.
@@ -211,13 +167,6 @@ pub(super) fn check_fn<'a, 'tcx>(
         check_panic_info_fn(tcx, panic_impl_did.expect_local(), fn_sig, decl, declared_ret_ty);
     }
 
-    // Check that a function marked as `#[alloc_error_handler]` has signature `fn(Layout) -> !`
-    if let Some(alloc_error_handler_did) = tcx.lang_items().oom()
-        && alloc_error_handler_did == hir.local_def_id(fn_id).to_def_id()
-    {
-        check_alloc_error_fn(tcx, alloc_error_handler_did.expect_local(), fn_sig, decl, declared_ret_ty);
-    }
-
     (fcx, gen_ty)
 }
 
@@ -273,52 +222,3 @@ fn check_panic_info_fn(
         tcx.sess.span_err(span, "should have no const parameters");
     }
 }
-
-fn check_alloc_error_fn(
-    tcx: TyCtxt<'_>,
-    fn_id: LocalDefId,
-    fn_sig: ty::FnSig<'_>,
-    decl: &hir::FnDecl<'_>,
-    declared_ret_ty: Ty<'_>,
-) {
-    let Some(alloc_layout_did) = tcx.lang_items().alloc_layout() else {
-        tcx.sess.err("language item required, but not found: `alloc_layout`");
-        return;
-    };
-
-    if *declared_ret_ty.kind() != ty::Never {
-        tcx.sess.span_err(decl.output.span(), "return type should be `!`");
-    }
-
-    let inputs = fn_sig.inputs();
-    if inputs.len() != 1 {
-        tcx.sess.span_err(tcx.def_span(fn_id), "function should have one argument");
-        return;
-    }
-
-    let arg_is_alloc_layout = match inputs[0].kind() {
-        ty::Adt(ref adt, _) => adt.did() == alloc_layout_did,
-        _ => false,
-    };
-
-    if !arg_is_alloc_layout {
-        tcx.sess.span_err(decl.inputs[0].span, "argument should be `Layout`");
-    }
-
-    let DefKind::Fn = tcx.def_kind(fn_id) else {
-        let span = tcx.def_span(fn_id);
-        tcx.sess.span_err(span, "`#[alloc_error_handler]` should be a function");
-        return;
-    };
-
-    let generic_counts = tcx.generics_of(fn_id).own_counts();
-    if generic_counts.types != 0 {
-        let span = tcx.def_span(fn_id);
-        tcx.sess.span_err(span, "`#[alloc_error_handler]` function should have no type parameters");
-    }
-    if generic_counts.consts != 0 {
-        let span = tcx.def_span(fn_id);
-        tcx.sess
-            .span_err(span, "`#[alloc_error_handler]` function should have no const parameters");
-    }
-}
diff --git a/compiler/rustc_hir_typeck/src/closure.rs b/compiler/rustc_hir_typeck/src/closure.rs
index a5a45f75e0e2..63062761b500 100644
--- a/compiler/rustc_hir_typeck/src/closure.rs
+++ b/compiler/rustc_hir_typeck/src/closure.rs
@@ -10,18 +10,20 @@ use rustc_hir_analysis::astconv::AstConv;
 use rustc_infer::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKind};
 use rustc_infer::infer::LateBoundRegionConversionTime;
 use rustc_infer::infer::{InferOk, InferResult};
+use rustc_macros::{TypeFoldable, TypeVisitable};
 use rustc_middle::ty::subst::InternalSubsts;
 use rustc_middle::ty::visit::TypeVisitable;
 use rustc_middle::ty::{self, Ty};
 use rustc_span::source_map::Span;
 use rustc_target::spec::abi::Abi;
+use rustc_trait_selection::traits;
 use rustc_trait_selection::traits::error_reporting::ArgKind;
 use rustc_trait_selection::traits::error_reporting::InferCtxtExt as _;
 use std::cmp;
 use std::iter;
 
 /// What signature do we *expect* the closure to have from context?
-#[derive(Debug)]
+#[derive(Debug, Clone, TypeFoldable, TypeVisitable)]
 struct ExpectedSig<'tcx> {
     /// Span that gave us this expectation, if we know that.
     cause_span: Option<Span>,
@@ -33,7 +35,7 @@ struct ClosureSignatures<'tcx> {
     bound_sig: ty::PolyFnSig<'tcx>,
     /// The signature within the function body.
     /// This mostly differs in the sense that lifetimes are now early bound and any
-    /// opaque types from the signature expectation are overriden in case there are
+    /// opaque types from the signature expectation are overridden in case there are
     /// explicit hidden types written by the user in the closure signature.
     liberated_sig: ty::FnSig<'tcx>,
 }
@@ -82,8 +84,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         debug!(?bound_sig, ?liberated_sig);
 
-        let return_type_pre_known = !liberated_sig.output().is_ty_infer();
-
         let generator_types = check_fn(
             self,
             self.param_env.without_const(),
@@ -92,7 +92,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             expr.hir_id,
             body,
             gen,
-            return_type_pre_known,
         )
         .1;
 
@@ -174,34 +173,9 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         expected_ty: Ty<'tcx>,
     ) -> (Option<ExpectedSig<'tcx>>, Option<ty::ClosureKind>) {
         match *expected_ty.kind() {
-            ty::Opaque(def_id, substs) => {
-                let bounds = self.tcx.bound_explicit_item_bounds(def_id);
-                let sig =
-                    bounds.subst_iter_copied(self.tcx, substs).find_map(|(pred, span)| match pred
-                        .kind()
-                        .skip_binder()
-                    {
-                        ty::PredicateKind::Projection(proj_predicate) => self
-                            .deduce_sig_from_projection(
-                                Some(span),
-                                pred.kind().rebind(proj_predicate),
-                            ),
-                        _ => None,
-                    });
-
-                let kind = bounds
-                    .0
-                    .iter()
-                    .filter_map(|(pred, _)| match pred.kind().skip_binder() {
-                        ty::PredicateKind::Trait(tp) => {
-                            self.tcx.fn_trait_kind_from_lang_item(tp.def_id())
-                        }
-                        _ => None,
-                    })
-                    .fold(None, |best, cur| Some(best.map_or(cur, |best| cmp::min(best, cur))));
-                trace!(?sig, ?kind);
-                (sig, kind)
-            }
+            ty::Opaque(def_id, substs) => self.deduce_signature_from_predicates(
+                self.tcx.bound_explicit_item_bounds(def_id).subst_iter_copied(self.tcx, substs),
+            ),
             ty::Dynamic(ref object_type, ..) => {
                 let sig = object_type.projection_bounds().find_map(|pb| {
                     let pb = pb.with_self_ty(self.tcx, self.tcx.types.trait_object_dummy_self);
@@ -212,7 +186,9 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     .and_then(|did| self.tcx.fn_trait_kind_from_lang_item(did));
                 (sig, kind)
             }
-            ty::Infer(ty::TyVar(vid)) => self.deduce_expectations_from_obligations(vid),
+            ty::Infer(ty::TyVar(vid)) => self.deduce_signature_from_predicates(
+                self.obligations_for_self_ty(vid).map(|obl| (obl.predicate, obl.cause.span)),
+            ),
             ty::FnPtr(sig) => {
                 let expected_sig = ExpectedSig { cause_span: None, sig };
                 (Some(expected_sig), Some(ty::ClosureKind::Fn))
@@ -221,37 +197,57 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         }
     }
 
-    fn deduce_expectations_from_obligations(
+    fn deduce_signature_from_predicates(
         &self,
-        expected_vid: ty::TyVid,
+        predicates: impl DoubleEndedIterator<Item = (ty::Predicate<'tcx>, Span)>,
     ) -> (Option<ExpectedSig<'tcx>>, Option<ty::ClosureKind>) {
-        let expected_sig =
-            self.obligations_for_self_ty(expected_vid).find_map(|(_, obligation)| {
-                debug!(?obligation.predicate);
+        let mut expected_sig = None;
+        let mut expected_kind = None;
 
-                let bound_predicate = obligation.predicate.kind();
-                if let ty::PredicateKind::Projection(proj_predicate) =
-                    obligation.predicate.kind().skip_binder()
-                {
-                    // Given a Projection predicate, we can potentially infer
-                    // the complete signature.
+        for obligation in traits::elaborate_predicates_with_span(
+            self.tcx,
+            // Reverse the obligations here, since `elaborate_*` uses a stack,
+            // and we want to keep inference generally in the same order of
+            // the registered obligations.
+            predicates.rev(),
+        ) {
+            debug!(?obligation.predicate);
+            let bound_predicate = obligation.predicate.kind();
+
+            // Given a Projection predicate, we can potentially infer
+            // the complete signature.
+            if expected_sig.is_none()
+                && let ty::PredicateKind::Projection(proj_predicate) = bound_predicate.skip_binder()
+            {
+                expected_sig = self.normalize_associated_types_in(
+                    obligation.cause.span,
                     self.deduce_sig_from_projection(
-                        Some(obligation.cause.span),
+                    Some(obligation.cause.span),
                         bound_predicate.rebind(proj_predicate),
-                    )
-                } else {
-                    None
-                }
-            });
+                    ),
+                );
+            }
 
-        // Even if we can't infer the full signature, we may be able to
-        // infer the kind. This can occur when we elaborate a predicate
-        // like `F : Fn<A>`. Note that due to subtyping we could encounter
-        // many viable options, so pick the most restrictive.
-        let expected_kind = self
-            .obligations_for_self_ty(expected_vid)
-            .filter_map(|(tr, _)| self.tcx.fn_trait_kind_from_lang_item(tr.def_id()))
-            .fold(None, |best, cur| Some(best.map_or(cur, |best| cmp::min(best, cur))));
+            // Even if we can't infer the full signature, we may be able to
+            // infer the kind. This can occur when we elaborate a predicate
+            // like `F : Fn<A>`. Note that due to subtyping we could encounter
+            // many viable options, so pick the most restrictive.
+            let trait_def_id = match bound_predicate.skip_binder() {
+                ty::PredicateKind::Projection(data) => {
+                    Some(data.projection_ty.trait_def_id(self.tcx))
+                }
+                ty::PredicateKind::Trait(data) => Some(data.def_id()),
+                _ => None,
+            };
+            if let Some(closure_kind) =
+                trait_def_id.and_then(|def_id| self.tcx.fn_trait_kind_from_lang_item(def_id))
+            {
+                expected_kind = Some(
+                    expected_kind
+                        .map_or_else(|| closure_kind, |current| cmp::min(current, closure_kind)),
+                );
+            }
+        }
 
         (expected_sig, expected_kind)
     }
@@ -689,7 +685,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         let output_ty = match *ret_ty.kind() {
             ty::Infer(ty::TyVar(ret_vid)) => {
-                self.obligations_for_self_ty(ret_vid).find_map(|(_, obligation)| {
+                self.obligations_for_self_ty(ret_vid).find_map(|obligation| {
                     get_future_output(obligation.predicate, obligation.cause.span)
                 })?
             }
diff --git a/compiler/rustc_hir_typeck/src/coercion.rs b/compiler/rustc_hir_typeck/src/coercion.rs
index 86597a703e83..71949b421181 100644
--- a/compiler/rustc_hir_typeck/src/coercion.rs
+++ b/compiler/rustc_hir_typeck/src/coercion.rs
@@ -62,6 +62,7 @@ use rustc_span::{self, BytePos, DesugaringKind, Span};
 use rustc_target::spec::abi::Abi;
 use rustc_trait_selection::infer::InferCtxtExt as _;
 use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt as _;
+use rustc_trait_selection::traits::TraitEngineExt as _;
 use rustc_trait_selection::traits::{self, ObligationCause, ObligationCauseCode};
 
 use smallvec::{smallvec, SmallVec};
@@ -705,12 +706,7 @@ impl<'f, 'tcx> Coerce<'f, 'tcx> {
 
                 // Object safety violations or miscellaneous.
                 Err(err) => {
-                    self.err_ctxt().report_selection_error(
-                        obligation.clone(),
-                        &obligation,
-                        &err,
-                        false,
-                    );
+                    self.err_ctxt().report_selection_error(obligation.clone(), &obligation, &err);
                     // Treat this like an obligation and follow through
                     // with the unsizing - the lack of a coercion should
                     // be silent, as it causes a type mismatch later.
@@ -1043,7 +1039,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             let Ok(ok) = coerce.coerce(source, target) else {
                 return false;
             };
-            let mut fcx = traits::FulfillmentContext::new_in_snapshot();
+            let mut fcx = <dyn TraitEngine<'tcx>>::new_in_snapshot(self.tcx);
             fcx.register_predicate_obligations(self, ok.obligations);
             fcx.select_where_possible(&self).is_empty()
         })
@@ -1644,9 +1640,9 @@ impl<'tcx, 'exprs, E: AsCoercionSite> CoerceMany<'tcx, 'exprs, E> {
                 if visitor.ret_exprs.len() > 0 && let Some(expr) = expression {
                     self.note_unreachable_loop_return(&mut err, &expr, &visitor.ret_exprs);
                 }
-                err.emit_unless(unsized_return);
+                let reported = err.emit_unless(unsized_return);
 
-                self.final_ty = Some(fcx.tcx.ty_error());
+                self.final_ty = Some(fcx.tcx.ty_error_with_guaranteed(reported));
             }
         }
     }
@@ -1782,7 +1778,8 @@ impl<'tcx, 'exprs, E: AsCoercionSite> CoerceMany<'tcx, 'exprs, E> {
             // may occur at the first return expression we see in the closure
             // (if it conflicts with the declared return type). Skip adding a
             // note in this case, since it would be incorrect.
-            && !fcx.return_type_pre_known
+            && let Some(fn_sig) = fcx.body_fn_sig()
+            && fn_sig.output().is_ty_var()
         {
             err.span_note(
                 sp,
diff --git a/compiler/rustc_hir_typeck/src/demand.rs b/compiler/rustc_hir_typeck/src/demand.rs
index 2974ac97f236..9ca7730daa68 100644
--- a/compiler/rustc_hir_typeck/src/demand.rs
+++ b/compiler/rustc_hir_typeck/src/demand.rs
@@ -30,6 +30,10 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         expected_ty_expr: Option<&'tcx hir::Expr<'tcx>>,
         error: Option<TypeError<'tcx>>,
     ) {
+        if expr_ty == expected {
+            return;
+        }
+
         self.annotate_expected_due_to_let_ty(err, expr, error);
 
         // Use `||` to give these suggestions a precedence
@@ -42,7 +46,9 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             || self.suggest_boxing_when_appropriate(err, expr, expected, expr_ty)
             || self.suggest_block_to_brackets_peeling_refs(err, expr, expr_ty, expected)
             || self.suggest_copied_or_cloned(err, expr, expr_ty, expected)
-            || self.suggest_into(err, expr, expr_ty, expected);
+            || self.suggest_into(err, expr, expr_ty, expected)
+            || self.suggest_option_to_bool(err, expr, expr_ty, expected)
+            || self.suggest_floating_point_literal(err, expr, expected);
 
         self.note_type_is_not_clone(err, expected, expr_ty, expr);
         self.note_need_for_fn_pointer(err, expected, expr_ty);
@@ -530,24 +536,29 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         checked_ty: Ty<'tcx>,
         hir_id: hir::HirId,
     ) -> Vec<AssocItem> {
-        let mut methods =
-            self.probe_for_return_type(span, probe::Mode::MethodCall, expected, checked_ty, hir_id);
-        methods.retain(|m| {
-            self.has_only_self_parameter(m)
-                && self
-                    .tcx
-                    // This special internal attribute is used to permit
-                    // "identity-like" conversion methods to be suggested here.
-                    //
-                    // FIXME (#46459 and #46460): ideally
-                    // `std::convert::Into::into` and `std::borrow:ToOwned` would
-                    // also be `#[rustc_conversion_suggestion]`, if not for
-                    // method-probing false-positives and -negatives (respectively).
-                    //
-                    // FIXME? Other potential candidate methods: `as_ref` and
-                    // `as_mut`?
-                    .has_attr(m.def_id, sym::rustc_conversion_suggestion)
-        });
+        let methods = self.probe_for_return_type(
+            span,
+            probe::Mode::MethodCall,
+            expected,
+            checked_ty,
+            hir_id,
+            |m| {
+                self.has_only_self_parameter(m)
+                    && self
+                        .tcx
+                        // This special internal attribute is used to permit
+                        // "identity-like" conversion methods to be suggested here.
+                        //
+                        // FIXME (#46459 and #46460): ideally
+                        // `std::convert::Into::into` and `std::borrow:ToOwned` would
+                        // also be `#[rustc_conversion_suggestion]`, if not for
+                        // method-probing false-positives and -negatives (respectively).
+                        //
+                        // FIXME? Other potential candidate methods: `as_ref` and
+                        // `as_mut`?
+                        .has_attr(m.def_id, sym::rustc_conversion_suggestion)
+            },
+        );
 
         methods
     }
@@ -714,7 +725,14 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         expr: &hir::Expr<'tcx>,
         checked_ty: Ty<'tcx>,
         expected: Ty<'tcx>,
-    ) -> Option<(Span, String, String, Applicability, bool /* verbose */)> {
+    ) -> Option<(
+        Span,
+        String,
+        String,
+        Applicability,
+        bool, /* verbose */
+        bool, /* suggest `&` or `&mut` type annotation */
+    )> {
         let sess = self.sess();
         let sp = expr.span;
 
@@ -746,6 +764,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                     String::new(),
                                     Applicability::MachineApplicable,
                                     true,
+                                    false,
                                 ));
                             }
                         }
@@ -760,6 +779,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                     "b".to_string(),
                                     Applicability::MachineApplicable,
                                     true,
+                                    false,
                                 ));
                     }
                 }
@@ -817,6 +837,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                 sugg.2,
                                 Applicability::MachineApplicable,
                                 false,
+                                false,
                             ));
                         }
 
@@ -844,6 +865,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                 format!("{prefix}&mut {sugg_expr}"),
                                 Applicability::MachineApplicable,
                                 false,
+                                false,
                             ),
                             hir::Mutability::Not => (
                                 sp,
@@ -851,6 +873,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                 format!("{prefix}&{sugg_expr}"),
                                 Applicability::MachineApplicable,
                                 false,
+                                false,
                             ),
                         });
                     }
@@ -880,6 +903,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                             String::new(),
                             Applicability::MachineApplicable,
                             true,
+                            true
                         ));
                     }
                     return None;
@@ -893,6 +917,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         String::new(),
                         Applicability::MachineApplicable,
                         true,
+                        true,
                     ));
                 }
             }
@@ -959,6 +984,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                             src,
                             applicability,
                             true,
+                            false,
                         ));
                     }
                 }
@@ -999,6 +1025,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                 Applicability::MachineApplicable
                             },
                             true,
+                            false,
                         ));
                     }
 
@@ -1050,6 +1077,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                             suggestion,
                             Applicability::MachineApplicable,
                             true,
+                            false,
                         ));
                     }
                 }
diff --git a/compiler/rustc_hir_typeck/src/errors.rs b/compiler/rustc_hir_typeck/src/errors.rs
index 175037f9b3a1..afac6e7d94a8 100644
--- a/compiler/rustc_hir_typeck/src/errors.rs
+++ b/compiler/rustc_hir_typeck/src/errors.rs
@@ -113,8 +113,9 @@ pub struct MissingParentheseInRange {
 }
 
 #[derive(Subdiagnostic)]
-#[multipart_suggestion_verbose(
+#[multipart_suggestion(
     hir_analysis_add_missing_parentheses_in_range,
+    style = "verbose",
     applicability = "maybe-incorrect"
 )]
 pub struct AddMissingParenthesesInRange {
@@ -124,3 +125,11 @@ pub struct AddMissingParenthesesInRange {
     #[suggestion_part(code = ")")]
     pub right: Span,
 }
+
+#[derive(Diagnostic)]
+#[diag(hir_analysis_op_trait_generic_params)]
+pub struct OpMethodGenericParams {
+    #[primary_span]
+    pub span: Span,
+    pub method_name: String,
+}
diff --git a/compiler/rustc_hir_typeck/src/expr.rs b/compiler/rustc_hir_typeck/src/expr.rs
index 41b00fda03eb..e948d832e328 100644
--- a/compiler/rustc_hir_typeck/src/expr.rs
+++ b/compiler/rustc_hir_typeck/src/expr.rs
@@ -80,14 +80,14 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         // coercions from ! to `expected`.
         if ty.is_never() {
             if let Some(adjustments) = self.typeck_results.borrow().adjustments().get(expr.hir_id) {
-                self.tcx().sess.delay_span_bug(
+                let reported = self.tcx().sess.delay_span_bug(
                     expr.span,
                     "expression with never type wound up being adjusted",
                 );
                 return if let [Adjustment { kind: Adjust::NeverToAny, target }] = &adjustments[..] {
                     target.to_owned()
                 } else {
-                    self.tcx().ty_error()
+                    self.tcx().ty_error_with_guaranteed(reported)
                 };
             }
 
@@ -103,8 +103,16 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         }
 
         if let Some(mut err) = self.demand_suptype_diag(expr.span, expected_ty, ty) {
-            let expr = expr.peel_drop_temps();
-            self.suggest_deref_ref_or_into(&mut err, expr, expected_ty, ty, None);
+            // FIXME(compiler-errors): We probably should fold some of the
+            // `suggest_` functions from  `emit_coerce_suggestions` into here,
+            // since some of those aren't necessarily just coerce suggestions.
+            let _ = self.suggest_deref_ref_or_into(
+                &mut err,
+                expr.peel_drop_temps(),
+                expected_ty,
+                ty,
+                None,
+            ) || self.suggest_option_to_bool(&mut err, expr, ty, expected_ty);
             extend_err(&mut err);
             err.emit();
         }
@@ -220,7 +228,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         // Hide the outer diverging and has_errors flags.
         let old_diverges = self.diverges.replace(Diverges::Maybe);
-        let old_has_errors = self.has_errors.replace(false);
 
         let ty = ensure_sufficient_stack(|| match &expr.kind {
             hir::ExprKind::Path(
@@ -259,7 +266,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         // Combine the diverging and has_error flags.
         self.diverges.set(self.diverges.get() | old_diverges);
-        self.has_errors.set(self.has_errors.get() | old_has_errors);
 
         debug!("type of {} is...", self.tcx.hir().node_to_string(expr.hir_id));
         debug!("... {:?}, expected is {:?}", ty, expected);
@@ -398,8 +404,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         {
                             err.subdiagnostic(ExprParenthesesNeeded::surrounding(*sp));
                         }
-                        err.emit();
-                        oprnd_t = tcx.ty_error();
+                        oprnd_t = tcx.ty_error_with_guaranteed(err.emit());
                     }
                 }
                 hir::UnOp::Not => {
@@ -840,10 +845,12 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             return_expr_ty,
         );
 
-        if self.return_type_has_opaque {
+        if let Some(fn_sig) = self.body_fn_sig()
+            && fn_sig.output().has_opaque_types()
+        {
             // Point any obligations that were registered due to opaque type
             // inference at the return expression.
-            self.select_obligations_where_possible(false, |errors| {
+            self.select_obligations_where_possible(|errors| {
                 self.point_at_return_for_opaque_ty_error(errors, span, return_expr_ty);
             });
         }
@@ -1097,12 +1104,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
             // If the assignment expression itself is ill-formed, don't
             // bother emitting another error
-            if lhs_ty.references_error() || rhs_ty.references_error() {
-                err.delay_as_bug()
-            } else {
-                err.emit();
-            }
-            return self.tcx.ty_error();
+            let reported = err.emit_unless(lhs_ty.references_error() || rhs_ty.references_error());
+            return self.tcx.ty_error_with_guaranteed(reported);
         }
 
         let lhs_ty = self.check_expr_with_needs(&lhs, Needs::MutPlace);
@@ -1272,7 +1275,15 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         } else {
             // Defer other checks until we're done type checking.
             let mut deferred_cast_checks = self.deferred_cast_checks.borrow_mut();
-            match cast::CastCheck::new(self, e, t_expr, t_cast, t.span, expr.span) {
+            match cast::CastCheck::new(
+                self,
+                e,
+                t_expr,
+                t_cast,
+                t.span,
+                expr.span,
+                self.param_env.constness(),
+            ) {
                 Ok(cast_check) => {
                     debug!(
                         "check_expr_cast: deferring cast from {:?} to {:?}: {:?}",
@@ -2730,7 +2741,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 Some((index_ty, element_ty)) => {
                     // two-phase not needed because index_ty is never mutable
                     self.demand_coerce(idx, idx_t, index_ty, None, AllowTwoPhase::No);
-                    self.select_obligations_where_possible(false, |errors| {
+                    self.select_obligations_where_possible(|errors| {
                         self.point_at_index_if_possible(errors, idx.span)
                     });
                     element_ty
@@ -2769,8 +2780,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                             );
                         }
                     }
-                    err.emit();
-                    self.tcx.ty_error()
+                    let reported = err.emit();
+                    self.tcx.ty_error_with_guaranteed(reported)
                 }
             }
         }
diff --git a/compiler/rustc_hir_typeck/src/fallback.rs b/compiler/rustc_hir_typeck/src/fallback.rs
index 747ecb036b2a..5d44092a5f68 100644
--- a/compiler/rustc_hir_typeck/src/fallback.rs
+++ b/compiler/rustc_hir_typeck/src/fallback.rs
@@ -7,16 +7,16 @@ use rustc_data_structures::{
 use rustc_middle::ty::{self, Ty};
 
 impl<'tcx> FnCtxt<'_, 'tcx> {
-    /// Performs type inference fallback, returning true if any fallback
-    /// occurs.
-    pub(super) fn type_inference_fallback(&self) -> bool {
+    /// Performs type inference fallback, setting `FnCtxt::fallback_has_occurred`
+    /// if fallback has occurred.
+    pub(super) fn type_inference_fallback(&self) {
         debug!(
             "type-inference-fallback start obligations: {:#?}",
             self.fulfillment_cx.borrow_mut().pending_obligations()
         );
 
         // All type checking constraints were added, try to fallback unsolved variables.
-        self.select_obligations_where_possible(false, |_| {});
+        self.select_obligations_where_possible(|_| {});
 
         debug!(
             "type-inference-fallback post selection obligations: {:#?}",
@@ -26,18 +26,17 @@ impl<'tcx> FnCtxt<'_, 'tcx> {
         // Check if we have any unsolved variables. If not, no need for fallback.
         let unsolved_variables = self.unsolved_variables();
         if unsolved_variables.is_empty() {
-            return false;
+            return;
         }
 
         let diverging_fallback = self.calculate_diverging_fallback(&unsolved_variables);
 
-        let mut fallback_has_occurred = false;
         // We do fallback in two passes, to try to generate
         // better error messages.
         // The first time, we do *not* replace opaque types.
         for ty in unsolved_variables {
             debug!("unsolved_variable = {:?}", ty);
-            fallback_has_occurred |= self.fallback_if_possible(ty, &diverging_fallback);
+            self.fallback_if_possible(ty, &diverging_fallback);
         }
 
         // We now see if we can make progress. This might cause us to
@@ -63,9 +62,7 @@ impl<'tcx> FnCtxt<'_, 'tcx> {
         // If we had tried to fallback the opaque inference variable to `MyType`,
         // we will generate a confusing type-check error that does not explicitly
         // refer to opaque types.
-        self.select_obligations_where_possible(fallback_has_occurred, |_| {});
-
-        fallback_has_occurred
+        self.select_obligations_where_possible(|_| {});
     }
 
     // Tries to apply a fallback to `ty` if it is an unsolved variable.
@@ -81,12 +78,13 @@ impl<'tcx> FnCtxt<'_, 'tcx> {
     // Fallback becomes very dubious if we have encountered
     // type-checking errors.  In that case, fallback to Error.
     //
-    // The return value indicates whether fallback has occurred.
+    // Sets `FnCtxt::fallback_has_occurred` if fallback is performed
+    // during this call.
     fn fallback_if_possible(
         &self,
         ty: Ty<'tcx>,
         diverging_fallback: &FxHashMap<Ty<'tcx>, Ty<'tcx>>,
-    ) -> bool {
+    ) {
         // Careful: we do NOT shallow-resolve `ty`. We know that `ty`
         // is an unsolved variable, and we determine its fallback
         // based solely on how it was created, not what other type
@@ -111,7 +109,7 @@ impl<'tcx> FnCtxt<'_, 'tcx> {
             ty::Infer(ty::FloatVar(_)) => self.tcx.types.f64,
             _ => match diverging_fallback.get(&ty) {
                 Some(&fallback_ty) => fallback_ty,
-                None => return false,
+                None => return,
             },
         };
         debug!("fallback_if_possible(ty={:?}): defaulting to `{:?}`", ty, fallback);
@@ -122,7 +120,7 @@ impl<'tcx> FnCtxt<'_, 'tcx> {
             .map(|origin| origin.span)
             .unwrap_or(rustc_span::DUMMY_SP);
         self.demand_eqtype(span, ty, fallback);
-        true
+        self.fallback_has_occurred.set(true);
     }
 
     /// The "diverging fallback" system is rather complicated. This is
diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs
index 6a1cffe3e602..c6bd771fad25 100644
--- a/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs
+++ b/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs
@@ -18,11 +18,12 @@ use rustc_infer::infer::canonical::{Canonical, OriginalQueryValues, QueryRespons
 use rustc_infer::infer::error_reporting::TypeAnnotationNeeded::E0282;
 use rustc_infer::infer::{InferOk, InferResult};
 use rustc_middle::ty::adjustment::{Adjust, Adjustment, AutoBorrow, AutoBorrowMutability};
+use rustc_middle::ty::error::TypeError;
 use rustc_middle::ty::fold::TypeFoldable;
 use rustc_middle::ty::visit::TypeVisitable;
 use rustc_middle::ty::{
-    self, AdtKind, CanonicalUserType, DefIdTree, EarlyBinder, GenericParamDefKind, ToPolyTraitRef,
-    ToPredicate, Ty, UserType,
+    self, AdtKind, CanonicalUserType, DefIdTree, EarlyBinder, GenericParamDefKind, ToPredicate, Ty,
+    UserType,
 };
 use rustc_middle::ty::{GenericArgKind, InternalSubsts, SubstsRef, UserSelfTy, UserSubsts};
 use rustc_session::lint;
@@ -32,9 +33,7 @@ use rustc_span::symbol::{kw, sym, Ident};
 use rustc_span::{Span, DUMMY_SP};
 use rustc_trait_selection::infer::InferCtxtExt as _;
 use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt as _;
-use rustc_trait_selection::traits::{
-    self, ObligationCause, ObligationCauseCode, TraitEngine, TraitEngineExt,
-};
+use rustc_trait_selection::traits::{self, ObligationCause, ObligationCauseCode, ObligationCtxt};
 
 use std::collections::hash_map::Entry;
 use std::slice;
@@ -106,7 +105,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         // possible. This can help substantially when there are
         // indirect dependencies that don't seem worth tracking
         // precisely.
-        self.select_obligations_where_possible(false, mutate_fulfillment_errors);
+        self.select_obligations_where_possible(mutate_fulfillment_errors);
         self.resolve_vars_if_possible(ty)
     }
 
@@ -143,7 +142,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         self.typeck_results.borrow_mut().node_types_mut().insert(id, ty);
 
         if ty.references_error() {
-            self.has_errors.set(true);
             self.set_tainted_by_errors();
         }
     }
@@ -601,7 +599,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     pub(in super::super) fn resolve_generator_interiors(&self, def_id: DefId) {
         let mut generators = self.deferred_generator_interiors.borrow_mut();
         for (body_id, interior, kind) in generators.drain(..) {
-            self.select_obligations_where_possible(false, |_| {});
+            self.select_obligations_where_possible(|_| {});
             crate::generator_interior::resolve_interior(self, def_id, body_id, interior, kind);
         }
     }
@@ -612,25 +610,20 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         if !errors.is_empty() {
             self.adjust_fulfillment_errors_for_expr_obligation(&mut errors);
-            self.err_ctxt().report_fulfillment_errors(&errors, self.inh.body_id, false);
+            self.err_ctxt().report_fulfillment_errors(&errors, self.inh.body_id);
         }
     }
 
     /// Select as many obligations as we can at present.
     pub(in super::super) fn select_obligations_where_possible(
         &self,
-        fallback_has_occurred: bool,
         mutate_fulfillment_errors: impl Fn(&mut Vec<traits::FulfillmentError<'tcx>>),
     ) {
         let mut result = self.fulfillment_cx.borrow_mut().select_where_possible(self);
         if !result.is_empty() {
             mutate_fulfillment_errors(&mut result);
             self.adjust_fulfillment_errors_for_expr_obligation(&mut result);
-            self.err_ctxt().report_fulfillment_errors(
-                &result,
-                self.inh.body_id,
-                fallback_has_occurred,
-            );
+            self.err_ctxt().report_fulfillment_errors(&result, self.inh.body_id);
         }
     }
 
@@ -650,12 +643,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     }
 
     #[instrument(skip(self), level = "debug")]
-    fn self_type_matches_expected_vid(
-        &self,
-        trait_ref: ty::PolyTraitRef<'tcx>,
-        expected_vid: ty::TyVid,
-    ) -> bool {
-        let self_ty = self.shallow_resolve(trait_ref.skip_binder().self_ty());
+    fn self_type_matches_expected_vid(&self, self_ty: Ty<'tcx>, expected_vid: ty::TyVid) -> bool {
+        let self_ty = self.shallow_resolve(self_ty);
         debug!(?self_ty);
 
         match *self_ty.kind() {
@@ -674,54 +663,61 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     pub(in super::super) fn obligations_for_self_ty<'b>(
         &'b self,
         self_ty: ty::TyVid,
-    ) -> impl Iterator<Item = (ty::PolyTraitRef<'tcx>, traits::PredicateObligation<'tcx>)>
-    + Captures<'tcx>
-    + 'b {
+    ) -> impl DoubleEndedIterator<Item = traits::PredicateObligation<'tcx>> + Captures<'tcx> + 'b
+    {
         // FIXME: consider using `sub_root_var` here so we
         // can see through subtyping.
         let ty_var_root = self.root_var(self_ty);
         trace!("pending_obligations = {:#?}", self.fulfillment_cx.borrow().pending_obligations());
 
-        self.fulfillment_cx
-            .borrow()
-            .pending_obligations()
-            .into_iter()
-            .filter_map(move |obligation| {
-                let bound_predicate = obligation.predicate.kind();
-                match bound_predicate.skip_binder() {
-                    ty::PredicateKind::Projection(data) => Some((
-                        bound_predicate.rebind(data).required_poly_trait_ref(self.tcx),
-                        obligation,
-                    )),
-                    ty::PredicateKind::Trait(data) => {
-                        Some((bound_predicate.rebind(data).to_poly_trait_ref(), obligation))
-                    }
-                    ty::PredicateKind::Subtype(..) => None,
-                    ty::PredicateKind::Coerce(..) => None,
-                    ty::PredicateKind::RegionOutlives(..) => None,
-                    ty::PredicateKind::TypeOutlives(..) => None,
-                    ty::PredicateKind::WellFormed(..) => None,
-                    ty::PredicateKind::ObjectSafe(..) => None,
-                    ty::PredicateKind::ConstEvaluatable(..) => None,
-                    ty::PredicateKind::ConstEquate(..) => None,
-                    // N.B., this predicate is created by breaking down a
-                    // `ClosureType: FnFoo()` predicate, where
-                    // `ClosureType` represents some `Closure`. It can't
-                    // possibly be referring to the current closure,
-                    // because we haven't produced the `Closure` for
-                    // this closure yet; this is exactly why the other
-                    // code is looking for a self type of an unresolved
-                    // inference variable.
-                    ty::PredicateKind::ClosureKind(..) => None,
-                    ty::PredicateKind::TypeWellFormedFromEnv(..) => None,
+        self.fulfillment_cx.borrow().pending_obligations().into_iter().filter_map(
+            move |obligation| match &obligation.predicate.kind().skip_binder() {
+                ty::PredicateKind::Projection(data)
+                    if self.self_type_matches_expected_vid(
+                        data.projection_ty.self_ty(),
+                        ty_var_root,
+                    ) =>
+                {
+                    Some(obligation)
                 }
-            })
-            .filter(move |(tr, _)| self.self_type_matches_expected_vid(*tr, ty_var_root))
+                ty::PredicateKind::Trait(data)
+                    if self.self_type_matches_expected_vid(data.self_ty(), ty_var_root) =>
+                {
+                    Some(obligation)
+                }
+
+                ty::PredicateKind::Trait(..)
+                | ty::PredicateKind::Projection(..)
+                | ty::PredicateKind::Subtype(..)
+                | ty::PredicateKind::Coerce(..)
+                | ty::PredicateKind::RegionOutlives(..)
+                | ty::PredicateKind::TypeOutlives(..)
+                | ty::PredicateKind::WellFormed(..)
+                | ty::PredicateKind::ObjectSafe(..)
+                | ty::PredicateKind::ConstEvaluatable(..)
+                | ty::PredicateKind::ConstEquate(..)
+                // N.B., this predicate is created by breaking down a
+                // `ClosureType: FnFoo()` predicate, where
+                // `ClosureType` represents some `Closure`. It can't
+                // possibly be referring to the current closure,
+                // because we haven't produced the `Closure` for
+                // this closure yet; this is exactly why the other
+                // code is looking for a self type of an unresolved
+                // inference variable.
+                | ty::PredicateKind::ClosureKind(..)
+                | ty::PredicateKind::TypeWellFormedFromEnv(..) => None,
+            },
+        )
     }
 
     pub(in super::super) fn type_var_is_sized(&self, self_ty: ty::TyVid) -> bool {
-        self.obligations_for_self_ty(self_ty)
-            .any(|(tr, _)| Some(tr.def_id()) == self.tcx.lang_items().sized_trait())
+        let sized_did = self.tcx.lang_items().sized_trait();
+        self.obligations_for_self_ty(self_ty).any(|obligation| {
+            match obligation.predicate.kind().skip_binder() {
+                ty::PredicateKind::Trait(data) => Some(data.def_id()) == sized_did,
+                _ => false,
+            }
+        })
     }
 
     pub(in super::super) fn err_args(&self, len: usize) -> Vec<Ty<'tcx>> {
@@ -769,34 +765,16 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         let expect_args = self
             .fudge_inference_if_ok(|| {
+                let ocx = ObligationCtxt::new_in_snapshot(self);
+
                 // Attempt to apply a subtyping relationship between the formal
                 // return type (likely containing type variables if the function
                 // is polymorphic) and the expected return type.
                 // No argument expectations are produced if unification fails.
                 let origin = self.misc(call_span);
-                let ures = self.at(&origin, self.param_env).sup(ret_ty, formal_ret);
-
-                // FIXME(#27336) can't use ? here, Try::from_error doesn't default
-                // to identity so the resulting type is not constrained.
-                match ures {
-                    Ok(ok) => {
-                        // Process any obligations locally as much as
-                        // we can.  We don't care if some things turn
-                        // out unconstrained or ambiguous, as we're
-                        // just trying to get hints here.
-                        let errors = self.save_and_restore_in_snapshot_flag(|_| {
-                            let mut fulfill = <dyn TraitEngine<'_>>::new(self.tcx);
-                            for obligation in ok.obligations {
-                                fulfill.register_predicate_obligation(self, obligation);
-                            }
-                            fulfill.select_where_possible(self)
-                        });
-
-                        if !errors.is_empty() {
-                            return Err(());
-                        }
-                    }
-                    Err(_) => return Err(()),
+                ocx.sup(&origin, self.param_env, ret_ty, formal_ret)?;
+                if !ocx.select_where_possible().is_empty() {
+                    return Err(TypeError::Mismatch);
                 }
 
                 // Record all the argument types, with the substitutions
@@ -1215,9 +1193,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                             }
                         }
                     }
-                    err.emit();
-
-                    return (tcx.ty_error(), res);
+                    let reported = err.emit();
+                    return (tcx.ty_error_with_guaranteed(reported), res);
                 }
             }
         } else {
diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs
index 08a3cbccfb05..8cf70eb5431a 100644
--- a/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs
+++ b/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs
@@ -33,16 +33,27 @@ use rustc_span::{self, sym, Span};
 use rustc_trait_selection::traits::{self, ObligationCauseCode, SelectionContext};
 
 use std::iter;
+use std::mem;
 use std::ops::ControlFlow;
 use std::slice;
 
 impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
-    pub(in super::super) fn check_casts(&self) {
-        let mut deferred_cast_checks = self.deferred_cast_checks.borrow_mut();
+    pub(in super::super) fn check_casts(&mut self) {
+        // don't hold the borrow to deferred_cast_checks while checking to avoid borrow checker errors
+        // when writing to `self.param_env`.
+        let mut deferred_cast_checks = mem::take(&mut *self.deferred_cast_checks.borrow_mut());
+
         debug!("FnCtxt::check_casts: {} deferred checks", deferred_cast_checks.len());
         for cast in deferred_cast_checks.drain(..) {
+            let prev_env = self.param_env;
+            self.param_env = self.param_env.with_constness(cast.constness);
+
             cast.check(self);
+
+            self.param_env = prev_env;
         }
+
+        *self.deferred_cast_checks.borrow_mut() = deferred_cast_checks;
     }
 
     pub(in super::super) fn check_transmutes(&self) {
@@ -125,6 +136,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             tuple_arguments,
             Some(method.def_id),
         );
+
         method.sig.output()
     }
 
@@ -203,7 +215,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         "cannot use call notation; the first type parameter \
                          for the function trait is neither a tuple nor unit"
                     )
-                    .emit();
+                    .delay_as_bug();
                     (self.err_args(provided_args.len()), None)
                 }
             }
@@ -333,7 +345,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             // an "opportunistic" trait resolution of any trait bounds on
             // the call. This helps coercions.
             if check_closures {
-                self.select_obligations_where_possible(false, |_| {})
+                self.select_obligations_where_possible(|_| {})
             }
 
             // Check each argument, to satisfy the input it was provided for
@@ -585,6 +597,18 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             }
         };
 
+        let mk_trace = |span, (formal_ty, expected_ty), provided_ty| {
+            let mismatched_ty = if expected_ty == provided_ty {
+                // If expected == provided, then we must have failed to sup
+                // the formal type. Avoid printing out "expected Ty, found Ty"
+                // in that case.
+                formal_ty
+            } else {
+                expected_ty
+            };
+            TypeTrace::types(&self.misc(span), true, mismatched_ty, provided_ty)
+        };
+
         // The algorithm here is inspired by levenshtein distance and longest common subsequence.
         // We'll try to detect 4 different types of mistakes:
         // - An extra parameter has been provided that doesn't satisfy *any* of the other inputs
@@ -649,10 +673,9 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         // A tuple wrap suggestion actually occurs within,
                         // so don't do anything special here.
                         err = self.err_ctxt().report_and_explain_type_error(
-                            TypeTrace::types(
-                                &self.misc(*lo),
-                                true,
-                                formal_and_expected_inputs[mismatch_idx.into()].1,
+                            mk_trace(
+                                *lo,
+                                formal_and_expected_inputs[mismatch_idx.into()],
                                 provided_arg_tys[mismatch_idx.into()].0,
                             ),
                             terr,
@@ -736,9 +759,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         errors.drain_filter(|error| {
                 let Error::Invalid(provided_idx, expected_idx, Compatibility::Incompatible(Some(e))) = error else { return false };
                 let (provided_ty, provided_span) = provided_arg_tys[*provided_idx];
-                let (expected_ty, _) = formal_and_expected_inputs[*expected_idx];
-                let cause = &self.misc(provided_span);
-                let trace = TypeTrace::types(cause, true, expected_ty, provided_ty);
+                let trace = mk_trace(provided_span, formal_and_expected_inputs[*expected_idx], provided_ty);
                 if !matches!(trace.cause.as_failure_code(*e), FailureCode::Error0308(_)) {
                     self.err_ctxt().report_and_explain_type_error(trace, *e).emit();
                     return true;
@@ -762,8 +783,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         {
             let (formal_ty, expected_ty) = formal_and_expected_inputs[*expected_idx];
             let (provided_ty, provided_arg_span) = provided_arg_tys[*provided_idx];
-            let cause = &self.misc(provided_arg_span);
-            let trace = TypeTrace::types(cause, true, expected_ty, provided_ty);
+            let trace = mk_trace(provided_arg_span, (formal_ty, expected_ty), provided_ty);
             let mut err = self.err_ctxt().report_and_explain_type_error(trace, *err);
             self.emit_coerce_suggestions(
                 &mut err,
@@ -835,8 +855,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     let (formal_ty, expected_ty) = formal_and_expected_inputs[expected_idx];
                     let (provided_ty, provided_span) = provided_arg_tys[provided_idx];
                     if let Compatibility::Incompatible(error) = compatibility {
-                        let cause = &self.misc(provided_span);
-                        let trace = TypeTrace::types(cause, true, expected_ty, provided_ty);
+                        let trace = mk_trace(provided_span, (formal_ty, expected_ty), provided_ty);
                         if let Some(e) = error {
                             self.err_ctxt().note_type_err(
                                 &mut err,
@@ -1323,7 +1342,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         // Hide the outer diverging and `has_errors` flags.
         let old_diverges = self.diverges.replace(Diverges::Maybe);
-        let old_has_errors = self.has_errors.replace(false);
 
         match stmt.kind {
             hir::StmtKind::Local(l) => {
@@ -1353,7 +1371,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         // Combine the diverging and `has_error` flags.
         self.diverges.set(self.diverges.get() | old_diverges);
-        self.has_errors.set(self.has_errors.get() | old_has_errors);
     }
 
     pub fn check_block_no_value(&self, blk: &'tcx hir::Block<'tcx>) {
@@ -1533,11 +1550,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             self.diverges.set(prev_diverges);
         }
 
-        let mut ty = ctxt.coerce.unwrap().complete(self);
-
-        if self.has_errors.get() || ty.references_error() {
-            ty = self.tcx.ty_error()
-        }
+        let ty = ctxt.coerce.unwrap().complete(self);
 
         self.write_ty(blk.hir_id, ty);
 
diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs
index 0c600daf4459..d5e4b6de581c 100644
--- a/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs
+++ b/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs
@@ -68,10 +68,6 @@ pub struct FnCtxt<'a, 'tcx> {
     /// any).
     pub(super) ret_coercion: Option<RefCell<DynamicCoerceMany<'tcx>>>,
 
-    /// Used exclusively to reduce cost of advanced evaluation used for
-    /// more helpful diagnostics.
-    pub(super) in_tail_expr: bool,
-
     /// First span of a return site that we find. Used in error messages.
     pub(super) ret_coercion_span: Cell<Option<Span>>,
 
@@ -112,21 +108,11 @@ pub struct FnCtxt<'a, 'tcx> {
     /// the diverges flag is set to something other than `Maybe`.
     pub(super) diverges: Cell<Diverges>,
 
-    /// Whether any child nodes have any type errors.
-    pub(super) has_errors: Cell<bool>,
-
     pub(super) enclosing_breakables: RefCell<EnclosingBreakables<'tcx>>,
 
     pub(super) inh: &'a Inherited<'tcx>,
 
-    /// True if the function or closure's return type is known before
-    /// entering the function/closure, i.e. if the return type is
-    /// either given explicitly or inferred from, say, an `Fn*` trait
-    /// bound. Used for diagnostic purposes only.
-    pub(super) return_type_pre_known: bool,
-
-    /// True if the return type has an Opaque type
-    pub(super) return_type_has_opaque: bool,
+    pub(super) fallback_has_occurred: Cell<bool>,
 }
 
 impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
@@ -140,19 +126,16 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             param_env,
             err_count_on_creation: inh.tcx.sess.err_count(),
             ret_coercion: None,
-            in_tail_expr: false,
             ret_coercion_span: Cell::new(None),
             resume_yield_tys: None,
             ps: Cell::new(UnsafetyState::function(hir::Unsafety::Normal, hir::CRATE_HIR_ID)),
             diverges: Cell::new(Diverges::Maybe),
-            has_errors: Cell::new(false),
             enclosing_breakables: RefCell::new(EnclosingBreakables {
                 stack: Vec::new(),
                 by_id: Default::default(),
             }),
             inh,
-            return_type_pre_known: true,
-            return_type_has_opaque: false,
+            fallback_has_occurred: Cell::new(false),
         }
     }
 
@@ -174,7 +157,11 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     ///
     /// [`InferCtxt::err_ctxt`]: infer::InferCtxt::err_ctxt
     pub fn err_ctxt(&'a self) -> TypeErrCtxt<'a, 'tcx> {
-        TypeErrCtxt { infcx: &self.infcx, typeck_results: Some(self.typeck_results.borrow()) }
+        TypeErrCtxt {
+            infcx: &self.infcx,
+            typeck_results: Some(self.typeck_results.borrow()),
+            fallback_has_occurred: self.fallback_has_occurred.get(),
+        }
     }
 
     pub fn errors_reported_since_creation(&self) -> bool {
@@ -194,8 +181,8 @@ impl<'a, 'tcx> AstConv<'tcx> for FnCtxt<'a, 'tcx> {
         self.tcx
     }
 
-    fn item_def_id(&self) -> Option<DefId> {
-        None
+    fn item_def_id(&self) -> DefId {
+        self.body_id.owner.to_def_id()
     }
 
     fn get_type_parameter_bounds(
diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs
index cd2e41aff0f1..06e6e4350fcb 100644
--- a/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs
+++ b/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs
@@ -13,7 +13,7 @@ use rustc_hir_analysis::astconv::AstConv;
 use rustc_infer::infer::{self, TyCtxtInferExt};
 use rustc_infer::traits::{self, StatementAsExpression};
 use rustc_middle::lint::in_external_macro;
-use rustc_middle::ty::{self, Binder, IsSuggestable, ToPredicate, Ty};
+use rustc_middle::ty::{self, Binder, DefIdTree, IsSuggestable, ToPredicate, Ty};
 use rustc_session::errors::ExprParenthesesNeeded;
 use rustc_span::symbol::sym;
 use rustc_span::Span;
@@ -22,6 +22,14 @@ use rustc_trait_selection::traits::error_reporting::DefIdOrName;
 use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt as _;
 
 impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
+    pub(crate) fn body_fn_sig(&self) -> Option<ty::FnSig<'tcx>> {
+        self.typeck_results
+            .borrow()
+            .liberated_fn_sigs()
+            .get(self.tcx.hir().get_parent_node(self.body_id))
+            .copied()
+    }
+
     pub(in super::super) fn suggest_semicolon_at_end(&self, span: Span, err: &mut Diagnostic) {
         err.span_suggestion_short(
             span.shrink_to_hi(),
@@ -327,7 +335,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         expected_ty_expr: Option<&'tcx hir::Expr<'tcx>>,
     ) -> bool {
         let expr = expr.peel_blocks();
-        if let Some((sp, msg, suggestion, applicability, verbose)) =
+        if let Some((sp, msg, suggestion, applicability, verbose, annotation)) =
             self.check_ref(expr, found, expected)
         {
             if verbose {
@@ -335,9 +343,50 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             } else {
                 err.span_suggestion(sp, &msg, suggestion, applicability);
             }
+            if annotation {
+                let suggest_annotation = match expr.peel_drop_temps().kind {
+                    hir::ExprKind::AddrOf(hir::BorrowKind::Ref, hir::Mutability::Not, _) => "&",
+                    hir::ExprKind::AddrOf(hir::BorrowKind::Ref, hir::Mutability::Mut, _) => "&mut ",
+                    _ => return true,
+                };
+                let mut tuple_indexes = Vec::new();
+                let mut expr_id = expr.hir_id;
+                for (parent_id, node) in self.tcx.hir().parent_iter(expr.hir_id) {
+                    match node {
+                        Node::Expr(&Expr { kind: ExprKind::Tup(subs), .. }) => {
+                            tuple_indexes.push(
+                                subs.iter()
+                                    .enumerate()
+                                    .find(|(_, sub_expr)| sub_expr.hir_id == expr_id)
+                                    .unwrap()
+                                    .0,
+                            );
+                            expr_id = parent_id;
+                        }
+                        Node::Local(local) => {
+                            if let Some(mut ty) = local.ty {
+                                while let Some(index) = tuple_indexes.pop() {
+                                    match ty.kind {
+                                        TyKind::Tup(tys) => ty = &tys[index],
+                                        _ => return true,
+                                    }
+                                }
+                                let annotation_span = ty.span;
+                                err.span_suggestion(
+                                    annotation_span.with_hi(annotation_span.lo()),
+                                    "alternatively, consider changing the type annotation",
+                                    suggest_annotation,
+                                    Applicability::MaybeIncorrect,
+                                );
+                            }
+                            break;
+                        }
+                        _ => break,
+                    }
+                }
+            }
             return true;
-        } else if self.suggest_else_fn_with_closure(err, expr, found, expected)
-        {
+        } else if self.suggest_else_fn_with_closure(err, expr, found, expected) {
             return true;
         } else if self.suggest_fn_call(err, expr, found, |output| self.can_coerce(output, expected))
             && let ty::FnDef(def_id, ..) = &found.kind()
@@ -1067,6 +1116,53 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         false
     }
 
+    /// When expecting a `bool` and finding an `Option`, suggests using `let Some(..)` or `.is_some()`
+    pub(crate) fn suggest_option_to_bool(
+        &self,
+        diag: &mut Diagnostic,
+        expr: &hir::Expr<'_>,
+        expr_ty: Ty<'tcx>,
+        expected_ty: Ty<'tcx>,
+    ) -> bool {
+        if !expected_ty.is_bool() {
+            return false;
+        }
+
+        let ty::Adt(def, _) = expr_ty.peel_refs().kind() else { return false; };
+        if !self.tcx.is_diagnostic_item(sym::Option, def.did()) {
+            return false;
+        }
+
+        let hir = self.tcx.hir();
+        let cond_parent = hir.parent_iter(expr.hir_id).skip_while(|(_, node)| {
+            matches!(node, hir::Node::Expr(hir::Expr { kind: hir::ExprKind::Binary(op, _, _), .. }) if op.node == hir::BinOpKind::And)
+        }).next();
+        // Don't suggest:
+        //     `let Some(_) = a.is_some() && b`
+        //                     ++++++++++
+        // since the user probably just misunderstood how `let else`
+        // and `&&` work together.
+        if let Some((_, hir::Node::Local(local))) = cond_parent
+            && let hir::PatKind::Path(qpath) | hir::PatKind::TupleStruct(qpath, _, _) = &local.pat.kind
+            && let hir::QPath::Resolved(None, path) = qpath
+            && let Some(did) = path.res.opt_def_id()
+                .and_then(|did| self.tcx.opt_parent(did))
+                .and_then(|did| self.tcx.opt_parent(did))
+            && self.tcx.is_diagnostic_item(sym::Option, did)
+        {
+            return false;
+        }
+
+        diag.span_suggestion(
+            expr.span.shrink_to_hi(),
+            "use `Option::is_some` to test if the `Option` has a value",
+            ".is_some()",
+            Applicability::MachineApplicable,
+        );
+
+        true
+    }
+
     /// Suggest wrapping the block in square brackets instead of curly braces
     /// in case the block was mistaken array syntax, e.g. `{ 1 }` -> `[ 1 ]`.
     pub(crate) fn suggest_block_to_brackets(
@@ -1108,6 +1204,48 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         }
     }
 
+    #[instrument(skip(self, err))]
+    pub(crate) fn suggest_floating_point_literal(
+        &self,
+        err: &mut Diagnostic,
+        expr: &hir::Expr<'_>,
+        expected_ty: Ty<'tcx>,
+    ) -> bool {
+        if !expected_ty.is_floating_point() {
+            return false;
+        }
+        match expr.kind {
+            ExprKind::Struct(QPath::LangItem(LangItem::Range, ..), [start, end], _) => {
+                err.span_suggestion_verbose(
+                    start.span.shrink_to_hi().with_hi(end.span.lo()),
+                    "remove the unnecessary `.` operator for a floating point literal",
+                    '.',
+                    Applicability::MaybeIncorrect,
+                );
+                true
+            }
+            ExprKind::Struct(QPath::LangItem(LangItem::RangeFrom, ..), [start], _) => {
+                err.span_suggestion_verbose(
+                    expr.span.with_lo(start.span.hi()),
+                    "remove the unnecessary `.` operator for a floating point literal",
+                    '.',
+                    Applicability::MaybeIncorrect,
+                );
+                true
+            }
+            ExprKind::Struct(QPath::LangItem(LangItem::RangeTo, ..), [end], _) => {
+                err.span_suggestion_verbose(
+                    expr.span.until(end.span),
+                    "remove the unnecessary `.` operator and add an integer part for a floating point literal",
+                    "0.",
+                    Applicability::MaybeIncorrect,
+                );
+                true
+            }
+            _ => false,
+        }
+    }
+
     fn is_loop(&self, id: hir::HirId) -> bool {
         let node = self.tcx.hir().get(id);
         matches!(node, Node::Expr(Expr { kind: ExprKind::Loop(..), .. }))
diff --git a/compiler/rustc_hir_typeck/src/generator_interior/mod.rs b/compiler/rustc_hir_typeck/src/generator_interior/mod.rs
index b7dd599cd432..7bbfb70f2c3a 100644
--- a/compiler/rustc_hir_typeck/src/generator_interior/mod.rs
+++ b/compiler/rustc_hir_typeck/src/generator_interior/mod.rs
@@ -13,10 +13,13 @@ use rustc_hir::def_id::DefId;
 use rustc_hir::hir_id::HirIdSet;
 use rustc_hir::intravisit::{self, Visitor};
 use rustc_hir::{Arm, Expr, ExprKind, Guard, HirId, Pat, PatKind};
+use rustc_infer::infer::RegionVariableOrigin;
 use rustc_middle::middle::region::{self, Scope, ScopeData, YieldData};
-use rustc_middle::ty::{self, RvalueScopes, Ty, TyCtxt, TypeVisitable};
+use rustc_middle::ty::fold::FnMutDelegate;
+use rustc_middle::ty::{self, BoundVariableKind, RvalueScopes, Ty, TyCtxt, TypeVisitable};
 use rustc_span::symbol::sym;
 use rustc_span::Span;
+use smallvec::{smallvec, SmallVec};
 
 mod drop_ranges;
 
@@ -211,31 +214,57 @@ pub fn resolve_interior<'a, 'tcx>(
 
     debug!("types in generator {:?}, span = {:?}", types, body.value.span);
 
-    let mut counter = 0;
+    // We want to deduplicate if the lifetimes are the same modulo some non-informative counter.
+    // So, we need to actually do two passes: first by type to anonymize (preserving information
+    // required for diagnostics), then a second pass over all captured types to reassign disjoint
+    // region indices.
     let mut captured_tys = FxHashSet::default();
     let type_causes: Vec<_> = types
         .into_iter()
         .filter_map(|mut cause| {
-            // Erase regions and canonicalize late-bound regions to deduplicate as many types as we
-            // can.
-            let ty = fcx.normalize_associated_types_in(cause.span, cause.ty);
-            let erased = fcx.tcx.erase_regions(ty);
-            if captured_tys.insert(erased) {
-                // Replace all regions inside the generator interior with late bound regions.
-                // Note that each region slot in the types gets a new fresh late bound region,
-                // which means that none of the regions inside relate to any other, even if
-                // typeck had previously found constraints that would cause them to be related.
-                let folded = fcx.tcx.fold_regions(erased, |_, current_depth| {
-                    let br = ty::BoundRegion {
-                        var: ty::BoundVar::from_u32(counter),
-                        kind: ty::BrAnon(counter),
-                    };
-                    let r = fcx.tcx.mk_region(ty::ReLateBound(current_depth, br));
-                    counter += 1;
-                    r
-                });
+            // Replace all regions inside the generator interior with late bound regions.
+            // Note that each region slot in the types gets a new fresh late bound region,
+            // which means that none of the regions inside relate to any other, even if
+            // typeck had previously found constraints that would cause them to be related.
 
-                cause.ty = folded;
+            let mut counter = 0;
+            let mut mk_bound_region = |span| {
+                let kind = ty::BrAnon(counter, span);
+                let var = ty::BoundVar::from_u32(counter);
+                counter += 1;
+                ty::BoundRegion { var, kind }
+            };
+            let ty = fcx.normalize_associated_types_in(cause.span, cause.ty);
+            let ty = fcx.tcx.fold_regions(ty, |region, current_depth| {
+                let br = match region.kind() {
+                    ty::ReVar(vid) => {
+                        let origin = fcx.region_var_origin(vid);
+                        match origin {
+                            RegionVariableOrigin::EarlyBoundRegion(span, _) => {
+                                mk_bound_region(Some(span))
+                            }
+                            _ => mk_bound_region(None),
+                        }
+                    }
+                    // FIXME: these should use `BrNamed`
+                    ty::ReEarlyBound(region) => {
+                        mk_bound_region(Some(fcx.tcx.def_span(region.def_id)))
+                    }
+                    ty::ReLateBound(_, ty::BoundRegion { kind, .. })
+                    | ty::ReFree(ty::FreeRegion { bound_region: kind, .. }) => match kind {
+                        ty::BoundRegionKind::BrAnon(_, span) => mk_bound_region(span),
+                        ty::BoundRegionKind::BrNamed(def_id, _) => {
+                            mk_bound_region(Some(fcx.tcx.def_span(def_id)))
+                        }
+                        ty::BoundRegionKind::BrEnv => mk_bound_region(None),
+                    },
+                    _ => mk_bound_region(None),
+                };
+                let r = fcx.tcx.mk_region(ty::ReLateBound(current_depth, br));
+                r
+            });
+            if captured_tys.insert(ty) {
+                cause.ty = ty;
                 Some(cause)
             } else {
                 None
@@ -243,11 +272,38 @@ pub fn resolve_interior<'a, 'tcx>(
         })
         .collect();
 
+    let mut bound_vars: SmallVec<[BoundVariableKind; 4]> = smallvec![];
+    let mut counter = 0;
+    // Optimization: If there is only one captured type, then we don't actually
+    // need to fold and reindex (since the first type doesn't change).
+    let type_causes = if captured_tys.len() > 0 {
+        // Optimization: Use `replace_escaping_bound_vars_uncached` instead of
+        // `fold_regions`, since we only have late bound regions, and it skips
+        // types without bound regions.
+        fcx.tcx.replace_escaping_bound_vars_uncached(
+            type_causes,
+            FnMutDelegate {
+                regions: &mut |br| {
+                    let kind = match br.kind {
+                        ty::BrAnon(_, span) => ty::BrAnon(counter, span),
+                        _ => br.kind,
+                    };
+                    let var = ty::BoundVar::from_usize(bound_vars.len());
+                    bound_vars.push(ty::BoundVariableKind::Region(kind));
+                    counter += 1;
+                    fcx.tcx.mk_region(ty::ReLateBound(ty::INNERMOST, ty::BoundRegion { var, kind }))
+                },
+                types: &mut |b| bug!("unexpected bound ty in binder: {b:?}"),
+                consts: &mut |b, ty| bug!("unexpected bound ct in binder: {b:?} {ty}"),
+            },
+        )
+    } else {
+        type_causes
+    };
+
     // Extract type components to build the witness type.
     let type_list = fcx.tcx.mk_type_list(type_causes.iter().map(|cause| cause.ty));
-    let bound_vars = fcx.tcx.mk_bound_variable_kinds(
-        (0..counter).map(|i| ty::BoundVariableKind::Region(ty::BrAnon(i))),
-    );
+    let bound_vars = fcx.tcx.mk_bound_variable_kinds(bound_vars.iter());
     let witness =
         fcx.tcx.mk_generator_witness(ty::Binder::bind_with_vars(type_list, bound_vars.clone()));
 
diff --git a/compiler/rustc_hir_typeck/src/lib.rs b/compiler/rustc_hir_typeck/src/lib.rs
index e862d577573b..183e80f2e084 100644
--- a/compiler/rustc_hir_typeck/src/lib.rs
+++ b/compiler/rustc_hir_typeck/src/lib.rs
@@ -52,7 +52,7 @@ pub use inherited::{Inherited, InheritedBuilder};
 use crate::check::check_fn;
 use crate::coercion::DynamicCoerceMany;
 use crate::gather_locals::GatherLocalsVisitor;
-use rustc_data_structures::fx::FxHashSet;
+use rustc_data_structures::unord::UnordSet;
 use rustc_errors::{struct_span_err, MultiSpan};
 use rustc_hir as hir;
 use rustc_hir::def::Res;
@@ -174,7 +174,7 @@ fn has_typeck_results(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
     }
 }
 
-fn used_trait_imports(tcx: TyCtxt<'_>, def_id: LocalDefId) -> &FxHashSet<LocalDefId> {
+fn used_trait_imports(tcx: TyCtxt<'_>, def_id: LocalDefId) -> &UnordSet<LocalDefId> {
     &*tcx.typeck(def_id).used_trait_imports
 }
 
@@ -209,6 +209,7 @@ fn diagnostic_only_typeck<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) -> &ty::T
     typeck_with_fallback(tcx, def_id, fallback)
 }
 
+#[instrument(level = "debug", skip(tcx, fallback), ret)]
 fn typeck_with_fallback<'tcx>(
     tcx: TyCtxt<'tcx>,
     def_id: LocalDefId,
@@ -250,7 +251,7 @@ fn typeck_with_fallback<'tcx>(
                 param_env,
                 fn_sig,
             );
-            check_fn(&inh, param_env, fn_sig, decl, id, body, None, true).0
+            check_fn(&inh, param_env, fn_sig, decl, id, body, None).0
         } else {
             let fcx = FnCtxt::new(&inh, param_env, body.value.hir_id);
             let expected_type = body_ty
@@ -316,12 +317,12 @@ fn typeck_with_fallback<'tcx>(
             fcx
         };
 
-        let fallback_has_occurred = fcx.type_inference_fallback();
+        fcx.type_inference_fallback();
 
         // Even though coercion casts provide type hints, we check casts after fallback for
         // backwards compatibility. This makes fallback a stronger type hint than a cast coercion.
         fcx.check_casts();
-        fcx.select_obligations_where_possible(fallback_has_occurred, |_| {});
+        fcx.select_obligations_where_possible(|_| {});
 
         // Closure and generator analysis may run after fallback
         // because they don't constrain other type variables.
@@ -458,7 +459,7 @@ fn report_unexpected_variant_res(tcx: TyCtxt<'_>, res: Res, qpath: &hir::QPath<'
 /// # fn f(x: (isize, isize)) {}
 /// f((1, 2));
 /// ```
-#[derive(Clone, Eq, PartialEq)]
+#[derive(Copy, Clone, Eq, PartialEq)]
 enum TupleArgumentsFlag {
     DontTupleArguments,
     TupleArguments,
diff --git a/compiler/rustc_hir_typeck/src/method/confirm.rs b/compiler/rustc_hir_typeck/src/method/confirm.rs
index be4ea9986222..d996d6ec610b 100644
--- a/compiler/rustc_hir_typeck/src/method/confirm.rs
+++ b/compiler/rustc_hir_typeck/src/method/confirm.rs
@@ -151,8 +151,7 @@ impl<'a, 'tcx> ConfirmContext<'a, 'tcx> {
     ) -> Ty<'tcx> {
         // Commit the autoderefs by calling `autoderef` again, but this
         // time writing the results into the various typeck results.
-        let mut autoderef =
-            self.autoderef_overloaded_span(self.span, unadjusted_self_ty, self.call_expr.span);
+        let mut autoderef = self.autoderef(self.call_expr.span, unadjusted_self_ty);
         let Some((ty, n)) = autoderef.nth(pick.autoderefs) else {
             return self.tcx.ty_error_with_message(
                 rustc_span::DUMMY_SP,
diff --git a/compiler/rustc_hir_typeck/src/method/mod.rs b/compiler/rustc_hir_typeck/src/method/mod.rs
index a1278edefbb7..4a8b77493654 100644
--- a/compiler/rustc_hir_typeck/src/method/mod.rs
+++ b/compiler/rustc_hir_typeck/src/method/mod.rs
@@ -10,6 +10,7 @@ mod suggest;
 pub use self::suggest::SelfSource;
 pub use self::MethodError::*;
 
+use crate::errors::OpMethodGenericParams;
 use crate::{Expectation, FnCtxt};
 use rustc_data_structures::sync::Lrc;
 use rustc_errors::{Applicability, Diagnostic};
@@ -55,8 +56,7 @@ pub enum MethodError<'tcx> {
     // not-in-scope traits which may work.
     PrivateMatch(DefKind, DefId, Vec<DefId>),
 
-    // Found a `Self: Sized` bound where `Self` is a trait object, also the caller may have
-    // forgotten to import a trait.
+    // Found a `Self: Sized` bound where `Self` is a trait object.
     IllegalSizedBound(Vec<DefId>, bool, Span),
 
     // Found a match, but the return type is wrong
@@ -444,7 +444,13 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         };
         let def_id = method_item.def_id;
         let generics = tcx.generics_of(def_id);
-        assert_eq!(generics.params.len(), 0);
+
+        if generics.params.len() != 0 {
+            tcx.sess.emit_fatal(OpMethodGenericParams {
+                span: tcx.def_span(method_item.def_id),
+                method_name: m_name.to_string(),
+            });
+        }
 
         debug!("lookup_in_trait_adjusted: method_item={:?}", method_item);
         let mut obligations = vec![];
diff --git a/compiler/rustc_hir_typeck/src/method/probe.rs b/compiler/rustc_hir_typeck/src/method/probe.rs
index 74cf2ac32aab..3fcd073f5979 100644
--- a/compiler/rustc_hir_typeck/src/method/probe.rs
+++ b/compiler/rustc_hir_typeck/src/method/probe.rs
@@ -252,7 +252,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     /// would result in an error (basically, the same criteria we
     /// would use to decide if a method is a plausible fit for
     /// ambiguity purposes).
-    #[instrument(level = "debug", skip(self))]
+    #[instrument(level = "debug", skip(self, candidate_filter))]
     pub fn probe_for_return_type(
         &self,
         span: Span,
@@ -260,6 +260,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         return_type: Ty<'tcx>,
         self_ty: Ty<'tcx>,
         scope_expr_id: hir::HirId,
+        candidate_filter: impl Fn(&ty::AssocItem) -> bool,
     ) -> Vec<ty::AssocItem> {
         let method_names = self
             .probe_op(
@@ -271,7 +272,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 self_ty,
                 scope_expr_id,
                 ProbeScope::AllTraits,
-                |probe_cx| Ok(probe_cx.candidate_method_names()),
+                |probe_cx| Ok(probe_cx.candidate_method_names(candidate_filter)),
             )
             .unwrap_or_default();
         method_names
@@ -474,10 +475,9 @@ fn method_autoderef_steps<'tcx>(
     let (ref infcx, goal, inference_vars) = tcx.infer_ctxt().build_with_canonical(DUMMY_SP, &goal);
     let ParamEnvAnd { param_env, value: self_ty } = goal;
 
-    let mut autoderef =
-        Autoderef::new(infcx, param_env, hir::CRATE_HIR_ID, DUMMY_SP, self_ty, DUMMY_SP)
-            .include_raw_pointers()
-            .silence_errors();
+    let mut autoderef = Autoderef::new(infcx, param_env, hir::CRATE_HIR_ID, DUMMY_SP, self_ty)
+        .include_raw_pointers()
+        .silence_errors();
     let mut reached_raw_pointer = false;
     let mut steps: Vec<_> = autoderef
         .by_ref()
@@ -966,12 +966,16 @@ impl<'a, 'tcx> ProbeContext<'a, 'tcx> {
         }
     }
 
-    fn candidate_method_names(&self) -> Vec<Ident> {
+    fn candidate_method_names(
+        &self,
+        candidate_filter: impl Fn(&ty::AssocItem) -> bool,
+    ) -> Vec<Ident> {
         let mut set = FxHashSet::default();
         let mut names: Vec<_> = self
             .inherent_candidates
             .iter()
             .chain(&self.extension_candidates)
+            .filter(|candidate| candidate_filter(&candidate.item))
             .filter(|candidate| {
                 if let Some(return_ty) = self.return_type {
                     self.matches_return_type(&candidate.item, None, return_ty)
@@ -1014,7 +1018,6 @@ impl<'a, 'tcx> ProbeContext<'a, 'tcx> {
 
         let out_of_scope_traits = match self.pick_core() {
             Some(Ok(p)) => vec![p.item.container_id(self.tcx)],
-            //Some(Ok(p)) => p.iter().map(|p| p.item.container().id()).collect(),
             Some(Err(MethodError::Ambiguity(v))) => v
                 .into_iter()
                 .map(|source| match source {
@@ -1689,7 +1692,7 @@ impl<'a, 'tcx> ProbeContext<'a, 'tcx> {
             pcx.allow_similar_names = true;
             pcx.assemble_inherent_candidates();
 
-            let method_names = pcx.candidate_method_names();
+            let method_names = pcx.candidate_method_names(|_| true);
             pcx.allow_similar_names = false;
             let applicable_close_candidates: Vec<ty::AssocItem> = method_names
                 .iter()
diff --git a/compiler/rustc_hir_typeck/src/method/suggest.rs b/compiler/rustc_hir_typeck/src/method/suggest.rs
index f4351bfa84ae..edfe12963dc6 100644
--- a/compiler/rustc_hir_typeck/src/method/suggest.rs
+++ b/compiler/rustc_hir_typeck/src/method/suggest.rs
@@ -14,19 +14,25 @@ use rustc_hir::def::DefKind;
 use rustc_hir::def_id::DefId;
 use rustc_hir::lang_items::LangItem;
 use rustc_hir::{ExprKind, Node, QPath};
-use rustc_infer::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKind};
+use rustc_infer::infer::{
+    type_variable::{TypeVariableOrigin, TypeVariableOriginKind},
+    RegionVariableOrigin,
+};
+use rustc_middle::infer::unify_key::{ConstVariableOrigin, ConstVariableOriginKind};
 use rustc_middle::traits::util::supertraits;
+use rustc_middle::ty::fast_reject::DeepRejectCtxt;
 use rustc_middle::ty::fast_reject::{simplify_type, TreatParams};
 use rustc_middle::ty::print::with_crate_prefix;
-use rustc_middle::ty::{self, DefIdTree, ToPredicate, Ty, TyCtxt, TypeVisitable};
+use rustc_middle::ty::{self, DefIdTree, GenericArgKind, ToPredicate, Ty, TyCtxt, TypeVisitable};
 use rustc_middle::ty::{IsSuggestable, ToPolyTraitRef};
 use rustc_span::symbol::{kw, sym, Ident};
 use rustc_span::Symbol;
 use rustc_span::{lev_distance, source_map, ExpnKind, FileName, MacroKind, Span};
+use rustc_trait_selection::traits::error_reporting::on_unimplemented::OnUnimplementedNote;
 use rustc_trait_selection::traits::error_reporting::on_unimplemented::TypeErrCtxtExt as _;
 use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt as _;
 use rustc_trait_selection::traits::{
-    FulfillmentError, Obligation, ObligationCause, ObligationCauseCode, OnUnimplementedNote,
+    FulfillmentError, Obligation, ObligationCause, ObligationCauseCode,
 };
 
 use std::cmp::Ordering;
@@ -106,7 +112,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         let report_candidates = |span: Span,
                                  err: &mut Diagnostic,
-                                 mut sources: Vec<CandidateSource>,
+                                 sources: &mut Vec<CandidateSource>,
                                  sugg_span: Span| {
             sources.sort();
             sources.dedup();
@@ -248,7 +254,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         match error {
             MethodError::NoMatch(NoMatchData {
-                static_candidates: static_sources,
+                mut static_candidates,
                 unsatisfied_predicates,
                 out_of_scope_traits,
                 lev_candidate,
@@ -256,15 +262,15 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             }) => {
                 let tcx = self.tcx;
 
-                let actual = self.resolve_vars_if_possible(rcvr_ty);
-                let ty_str = self.ty_to_string(actual);
+                let rcvr_ty = self.resolve_vars_if_possible(rcvr_ty);
+                let ty_str = self.ty_to_string(rcvr_ty);
                 let is_method = mode == Mode::MethodCall;
                 let item_kind = if is_method {
                     "method"
-                } else if actual.is_enum() {
+                } else if rcvr_ty.is_enum() {
                     "variant or associated item"
                 } else {
-                    match (item_name.as_str().chars().next(), actual.is_fresh_ty()) {
+                    match (item_name.as_str().chars().next(), rcvr_ty.is_fresh_ty()) {
                         (Some(name), false) if name.is_lowercase() => "function or associated item",
                         (Some(_), false) => "associated item",
                         (Some(_), true) | (None, false) => "variant or associated item",
@@ -273,24 +279,23 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 };
 
                 if self.suggest_wrapping_range_with_parens(
-                    tcx, actual, source, span, item_name, &ty_str,
+                    tcx, rcvr_ty, source, span, item_name, &ty_str,
                 ) || self.suggest_constraining_numerical_ty(
-                    tcx, actual, source, span, item_kind, item_name, &ty_str,
+                    tcx, rcvr_ty, source, span, item_kind, item_name, &ty_str,
                 ) {
                     return None;
                 }
-
                 span = item_name.span;
 
                 // Don't show generic arguments when the method can't be found in any implementation (#81576).
                 let mut ty_str_reported = ty_str.clone();
-                if let ty::Adt(_, generics) = actual.kind() {
+                if let ty::Adt(_, generics) = rcvr_ty.kind() {
                     if generics.len() > 0 {
-                        let mut autoderef = self.autoderef(span, actual);
+                        let mut autoderef = self.autoderef(span, rcvr_ty);
                         let candidate_found = autoderef.any(|(ty, _)| {
-                            if let ty::Adt(adt_deref, _) = ty.kind() {
+                            if let ty::Adt(adt_def, _) = ty.kind() {
                                 self.tcx
-                                    .inherent_impls(adt_deref.did())
+                                    .inherent_impls(adt_def.did())
                                     .iter()
                                     .filter_map(|def_id| self.associated_value(*def_id, item_name))
                                     .count()
@@ -315,16 +320,16 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     "no {} named `{}` found for {} `{}` in the current scope",
                     item_kind,
                     item_name,
-                    actual.prefix_string(self.tcx),
+                    rcvr_ty.prefix_string(self.tcx),
                     ty_str_reported,
                 );
-                if actual.references_error() {
+                if rcvr_ty.references_error() {
                     err.downgrade_to_delayed_bug();
                 }
 
                 if let Mode::MethodCall = mode && let SelfSource::MethodCall(cal) = source {
                     self.suggest_await_before_method(
-                        &mut err, item_name, actual, cal, span,
+                        &mut err, item_name, rcvr_ty, cal, span,
                     );
                 }
                 if let Some(span) = tcx.resolutions(()).confused_type_with_std_module.get(&span) {
@@ -335,7 +340,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         Applicability::MachineApplicable,
                     );
                 }
-                if let ty::RawPtr(_) = &actual.kind() {
+                if let ty::RawPtr(_) = &rcvr_ty.kind() {
                     err.note(
                         "try using `<*const T>::as_ref()` to get a reference to the \
                          type behind the pointer: https://doc.rust-lang.org/std/\
@@ -347,22 +352,19 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     );
                 }
 
-                let ty_span = match actual.kind() {
-                    ty::Param(param_type) => {
-                        let generics = self.tcx.generics_of(self.body_id.owner.to_def_id());
-                        let type_param = generics.type_param(param_type, self.tcx);
-                        Some(self.tcx.def_span(type_param.def_id))
-                    }
+                let ty_span = match rcvr_ty.kind() {
+                    ty::Param(param_type) => Some(
+                        param_type.span_from_generics(self.tcx, self.body_id.owner.to_def_id()),
+                    ),
                     ty::Adt(def, _) if def.did().is_local() => Some(tcx.def_span(def.did())),
                     _ => None,
                 };
-
                 if let Some(span) = ty_span {
                     err.span_label(
                         span,
                         format!(
                             "{item_kind} `{item_name}` not found for this {}",
-                            actual.prefix_string(self.tcx)
+                            rcvr_ty.prefix_string(self.tcx)
                         ),
                     );
                 }
@@ -386,7 +388,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
                 let mut custom_span_label = false;
 
-                if !static_sources.is_empty() {
+                if !static_candidates.is_empty() {
                     err.note(
                         "found the following associated functions; to be used as methods, \
                          functions must have a `self` parameter",
@@ -394,43 +396,26 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     err.span_label(span, "this is an associated function, not a method");
                     custom_span_label = true;
                 }
-                if static_sources.len() == 1 {
-                    let ty_str =
-                        if let Some(CandidateSource::Impl(impl_did)) = static_sources.get(0) {
-                            // When the "method" is resolved through dereferencing, we really want the
-                            // original type that has the associated function for accurate suggestions.
-                            // (#61411)
-                            let ty = tcx.at(span).type_of(*impl_did);
-                            match (&ty.peel_refs().kind(), &actual.peel_refs().kind()) {
-                                (ty::Adt(def, _), ty::Adt(def_actual, _)) if def == def_actual => {
-                                    // Use `actual` as it will have more `substs` filled in.
-                                    self.ty_to_value_string(actual.peel_refs())
-                                }
-                                _ => self.ty_to_value_string(ty.peel_refs()),
-                            }
-                        } else {
-                            self.ty_to_value_string(actual.peel_refs())
-                        };
-                    if let SelfSource::MethodCall(expr) = source {
-                        err.span_suggestion(
-                            expr.span.to(span),
-                            "use associated function syntax instead",
-                            format!("{}::{}", ty_str, item_name),
-                            Applicability::MachineApplicable,
-                        );
-                    } else {
-                        err.help(&format!("try with `{}::{}`", ty_str, item_name,));
-                    }
+                if static_candidates.len() == 1 {
+                    self.suggest_associated_call_syntax(
+                        &mut err,
+                        &static_candidates,
+                        rcvr_ty,
+                        source,
+                        item_name,
+                        args,
+                        sugg_span,
+                    );
 
-                    report_candidates(span, &mut err, static_sources, sugg_span);
-                } else if static_sources.len() > 1 {
-                    report_candidates(span, &mut err, static_sources, sugg_span);
+                    report_candidates(span, &mut err, &mut static_candidates, sugg_span);
+                } else if static_candidates.len() > 1 {
+                    report_candidates(span, &mut err, &mut static_candidates, sugg_span);
                 }
 
                 let mut bound_spans = vec![];
                 let mut restrict_type_params = false;
                 let mut unsatisfied_bounds = false;
-                if item_name.name == sym::count && self.is_slice_ty(actual, span) {
+                if item_name.name == sym::count && self.is_slice_ty(rcvr_ty, span) {
                     let msg = "consider using `len` instead";
                     if let SelfSource::MethodCall(_expr) = source {
                         err.span_suggestion_short(
@@ -444,7 +429,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     }
                     if let Some(iterator_trait) = self.tcx.get_diagnostic_item(sym::Iterator) {
                         let iterator_trait = self.tcx.def_path_str(iterator_trait);
-                        err.note(&format!("`count` is defined on `{iterator_trait}`, which `{actual}` does not implement"));
+                        err.note(&format!("`count` is defined on `{iterator_trait}`, which `{rcvr_ty}` does not implement"));
                     }
                 } else if !unsatisfied_predicates.is_empty() {
                     let mut type_params = FxHashMap::default();
@@ -496,24 +481,18 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                             if let (ty::Param(_), ty::PredicateKind::Trait(p)) =
                                 (self_ty.kind(), parent_pred.kind().skip_binder())
                             {
+                                let hir = self.tcx.hir();
                                 let node = match p.trait_ref.self_ty().kind() {
                                     ty::Param(_) => {
                                         // Account for `fn` items like in `issue-35677.rs` to
                                         // suggest restricting its type params.
-                                        let did = self.tcx.hir().body_owner_def_id(hir::BodyId {
-                                            hir_id: self.body_id,
-                                        });
-                                        Some(
-                                            self.tcx
-                                                .hir()
-                                                .get(self.tcx.hir().local_def_id_to_hir_id(did)),
-                                        )
+                                        let parent_body =
+                                            hir.body_owner(hir::BodyId { hir_id: self.body_id });
+                                        Some(hir.get(parent_body))
+                                    }
+                                    ty::Adt(def, _) => {
+                                        def.did().as_local().map(|def_id| hir.get_by_def_id(def_id))
                                     }
-                                    ty::Adt(def, _) => def.did().as_local().map(|def_id| {
-                                        self.tcx
-                                            .hir()
-                                            .get(self.tcx.hir().local_def_id_to_hir_id(def_id))
-                                    }),
                                     _ => None,
                                 };
                                 if let Some(hir::Node::Item(hir::Item { kind, .. })) = node {
@@ -605,7 +584,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         .iter()
                         .filter_map(|(p, parent, c)| c.as_ref().map(|c| (p, parent, c)))
                         .filter_map(|(p, parent, c)| match c.code() {
-                            ObligationCauseCode::ImplDerivedObligation(ref data) => {
+                            ObligationCauseCode::ImplDerivedObligation(data) => {
                                 Some((&data.derived, p, parent, data.impl_def_id, data))
                             }
                             _ => None,
@@ -620,22 +599,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         match self.tcx.hir().get_if_local(impl_def_id) {
                             // Unmet obligation comes from a `derive` macro, point at it once to
                             // avoid multiple span labels pointing at the same place.
-                            Some(Node::Item(hir::Item {
-                                kind: hir::ItemKind::Trait(..),
-                                ident,
-                                ..
-                            })) if matches!(
-                                ident.span.ctxt().outer_expn_data().kind,
-                                ExpnKind::Macro(MacroKind::Derive, _)
-                            ) =>
-                            {
-                                let span = ident.span.ctxt().outer_expn_data().call_site;
-                                let mut spans: MultiSpan = span.into();
-                                spans.push_span_label(span, derive_msg);
-                                let entry = spanned_predicates.entry(spans);
-                                entry.or_insert_with(|| (path, tr_self_ty, Vec::new())).2.push(p);
-                            }
-
                             Some(Node::Item(hir::Item {
                                 kind: hir::ItemKind::Impl(hir::Impl { of_trait, self_ty, .. }),
                                 ..
@@ -659,34 +622,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                 entry.or_insert_with(|| (path, tr_self_ty, Vec::new())).2.push(p);
                             }
 
-                            // Unmet obligation coming from a `trait`.
-                            Some(Node::Item(hir::Item {
-                                kind: hir::ItemKind::Trait(..),
-                                ident,
-                                span: item_span,
-                                ..
-                            })) if !matches!(
-                                ident.span.ctxt().outer_expn_data().kind,
-                                ExpnKind::Macro(MacroKind::Derive, _)
-                            ) =>
-                            {
-                                if let Some(pred) = parent_p {
-                                    // Done to add the "doesn't satisfy" `span_label`.
-                                    let _ = format_pred(*pred);
-                                }
-                                skip_list.insert(p);
-                                let mut spans = if cause.span != *item_span {
-                                    let mut spans: MultiSpan = cause.span.into();
-                                    spans.push_span_label(cause.span, unsatisfied_msg);
-                                    spans
-                                } else {
-                                    ident.span.into()
-                                };
-                                spans.push_span_label(ident.span, "in this trait");
-                                let entry = spanned_predicates.entry(spans);
-                                entry.or_insert_with(|| (path, tr_self_ty, Vec::new())).2.push(p);
-                            }
-
                             // Unmet obligation coming from an `impl`.
                             Some(Node::Item(hir::Item {
                                 kind:
@@ -695,19 +630,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                     }),
                                 span: item_span,
                                 ..
-                            })) if !matches!(
-                                self_ty.span.ctxt().outer_expn_data().kind,
-                                ExpnKind::Macro(MacroKind::Derive, _)
-                            ) && !matches!(
-                                of_trait.as_ref().map(|t| t
-                                    .path
-                                    .span
-                                    .ctxt()
-                                    .outer_expn_data()
-                                    .kind),
-                                Some(ExpnKind::Macro(MacroKind::Derive, _))
-                            ) =>
-                            {
+                            })) => {
                                 let sized_pred =
                                     unsatisfied_predicates.iter().any(|(pred, _, _)| {
                                         match pred.kind().skip_binder() {
@@ -759,7 +682,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                 let entry = spanned_predicates.entry(spans);
                                 entry.or_insert_with(|| (path, tr_self_ty, Vec::new())).2.push(p);
                             }
-                            _ => {}
+                            Some(_) => unreachable!(),
+                            None => (),
                         }
                     }
                     let mut spanned_predicates: Vec<_> = spanned_predicates.into_iter().collect();
@@ -844,7 +768,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                             .map(|(_, path)| path)
                             .collect::<Vec<_>>()
                             .join("\n");
-                        let actual_prefix = actual.prefix_string(self.tcx);
+                        let actual_prefix = rcvr_ty.prefix_string(self.tcx);
                         info!("unimplemented_traits.len() == {}", unimplemented_traits.len());
                         let (primary_message, label) =
                             if unimplemented_traits.len() == 1 && unimplemented_traits_only {
@@ -853,7 +777,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                     .next()
                                     .map(|(_, (trait_ref, obligation))| {
                                         if trait_ref.self_ty().references_error()
-                                            || actual.references_error()
+                                            || rcvr_ty.references_error()
                                         {
                                             // Avoid crashing.
                                             return (None, None);
@@ -863,7 +787,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                             .on_unimplemented_note(trait_ref, &obligation);
                                         (message, label)
                                     })
-                                    .unwrap_or((None, None))
+                                    .unwrap()
                             } else {
                                 (None, None)
                             };
@@ -889,7 +813,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 let label_span_not_found = |err: &mut Diagnostic| {
                     if unsatisfied_predicates.is_empty() {
                         err.span_label(span, format!("{item_kind} not found in `{ty_str}`"));
-                        let is_string_or_ref_str = match actual.kind() {
+                        let is_string_or_ref_str = match rcvr_ty.kind() {
                             ty::Ref(_, ty, _) => {
                                 ty.is_str()
                                     || matches!(
@@ -925,7 +849,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                                 // different from the received one
                                                 // So we avoid suggestion method with Box<Self>
                                                 // for instance
-                                                self.tcx.at(span).type_of(*def_id) != actual
+                                                self.tcx.at(span).type_of(*def_id) != rcvr_ty
                                                     && self.tcx.at(span).type_of(*def_id) != rcvr_ty
                                             }
                                             (Mode::Path, false, _) => true,
@@ -972,7 +896,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 // If the method name is the name of a field with a function or closure type,
                 // give a helping note that it has to be called as `(x.f)(...)`.
                 if let SelfSource::MethodCall(expr) = source {
-                    if !self.suggest_field_call(span, rcvr_ty, expr, item_name, &mut err)
+                    if !self.suggest_calling_field_as_fn(span, rcvr_ty, expr, item_name, &mut err)
                         && lev_candidate.is_none()
                         && !custom_span_label
                     {
@@ -982,13 +906,15 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     label_span_not_found(&mut err);
                 }
 
-                // Don't suggest (for example) `expr.field.method()` if `expr.method()`
-                // doesn't exist due to unsatisfied predicates.
+                // Don't suggest (for example) `expr.field.clone()` if `expr.clone()`
+                // can't be called due to `typeof(expr): Clone` not holding.
                 if unsatisfied_predicates.is_empty() {
-                    self.check_for_field_method(&mut err, source, span, actual, item_name);
+                    self.suggest_calling_method_on_field(
+                        &mut err, source, span, rcvr_ty, item_name,
+                    );
                 }
 
-                self.check_for_inner_self(&mut err, source, span, actual, item_name);
+                self.check_for_inner_self(&mut err, source, span, rcvr_ty, item_name);
 
                 bound_spans.sort();
                 bound_spans.dedup();
@@ -996,7 +922,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     err.span_label(span, &msg);
                 }
 
-                if actual.is_numeric() && actual.is_fresh() || restrict_type_params {
+                if rcvr_ty.is_numeric() && rcvr_ty.is_fresh() || restrict_type_params {
                 } else {
                     self.suggest_traits_to_import(
                         &mut err,
@@ -1007,14 +933,15 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         source,
                         out_of_scope_traits,
                         &unsatisfied_predicates,
+                        &static_candidates,
                         unsatisfied_bounds,
                     );
                 }
 
                 // Don't emit a suggestion if we found an actual method
                 // that had unsatisfied trait bounds
-                if unsatisfied_predicates.is_empty() && actual.is_enum() {
-                    let adt_def = actual.ty_adt_def().expect("enum is not an ADT");
+                if unsatisfied_predicates.is_empty() && rcvr_ty.is_enum() {
+                    let adt_def = rcvr_ty.ty_adt_def().expect("enum is not an ADT");
                     if let Some(suggestion) = lev_distance::find_best_match_for_name(
                         &adt_def.variants().iter().map(|s| s.name).collect::<Vec<_>>(),
                         item_name.name,
@@ -1029,7 +956,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     }
                 }
 
-                if item_name.name == sym::as_str && actual.peel_refs().is_str() {
+                if item_name.name == sym::as_str && rcvr_ty.peel_refs().is_str() {
                     let msg = "remove this method call";
                     let mut fallback_span = true;
                     if let SelfSource::MethodCall(expr) = source {
@@ -1079,7 +1006,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 return Some(err);
             }
 
-            MethodError::Ambiguity(sources) => {
+            MethodError::Ambiguity(mut sources) => {
                 let mut err = struct_span_err!(
                     self.sess(),
                     item_name.span,
@@ -1088,7 +1015,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 );
                 err.span_label(item_name.span, format!("multiple `{}` found", item_name));
 
-                report_candidates(span, &mut err, sources, sugg_span);
+                report_candidates(span, &mut err, &mut sources, sugg_span);
                 err.emit();
             }
 
@@ -1145,7 +1072,141 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         None
     }
 
-    fn suggest_field_call(
+    /// Suggest calling `Ty::method` if `.method()` isn't found because the method
+    /// doesn't take a `self` receiver.
+    fn suggest_associated_call_syntax(
+        &self,
+        err: &mut Diagnostic,
+        static_candidates: &Vec<CandidateSource>,
+        rcvr_ty: Ty<'tcx>,
+        source: SelfSource<'tcx>,
+        item_name: Ident,
+        args: Option<(&hir::Expr<'tcx>, &[hir::Expr<'tcx>])>,
+        sugg_span: Span,
+    ) {
+        let mut has_unsuggestable_args = false;
+        let ty_str = if let Some(CandidateSource::Impl(impl_did)) = static_candidates.get(0) {
+            // When the "method" is resolved through dereferencing, we really want the
+            // original type that has the associated function for accurate suggestions.
+            // (#61411)
+            let impl_ty = self.tcx.type_of(*impl_did);
+            let target_ty = self
+                .autoderef(sugg_span, rcvr_ty)
+                .find(|(rcvr_ty, _)| {
+                    DeepRejectCtxt { treat_obligation_params: TreatParams::AsInfer }
+                        .types_may_unify(*rcvr_ty, impl_ty)
+                })
+                .map_or(impl_ty, |(ty, _)| ty)
+                .peel_refs();
+            if let ty::Adt(def, substs) = target_ty.kind() {
+                // If there are any inferred arguments, (`{integer}`), we should replace
+                // them with underscores to allow the compiler to infer them
+                let infer_substs = self.tcx.mk_substs(substs.into_iter().map(|arg| {
+                    if !arg.is_suggestable(self.tcx, true) {
+                        has_unsuggestable_args = true;
+                        match arg.unpack() {
+                            GenericArgKind::Lifetime(_) => self
+                                .next_region_var(RegionVariableOrigin::MiscVariable(
+                                    rustc_span::DUMMY_SP,
+                                ))
+                                .into(),
+                            GenericArgKind::Type(_) => self
+                                .next_ty_var(TypeVariableOrigin {
+                                    span: rustc_span::DUMMY_SP,
+                                    kind: TypeVariableOriginKind::MiscVariable,
+                                })
+                                .into(),
+                            GenericArgKind::Const(arg) => self
+                                .next_const_var(
+                                    arg.ty(),
+                                    ConstVariableOrigin {
+                                        span: rustc_span::DUMMY_SP,
+                                        kind: ConstVariableOriginKind::MiscVariable,
+                                    },
+                                )
+                                .into(),
+                        }
+                    } else {
+                        arg
+                    }
+                }));
+
+                self.tcx.value_path_str_with_substs(def.did(), infer_substs)
+            } else {
+                self.ty_to_value_string(target_ty)
+            }
+        } else {
+            self.ty_to_value_string(rcvr_ty.peel_refs())
+        };
+        if let SelfSource::MethodCall(_) = source {
+            let first_arg = if let Some(CandidateSource::Impl(impl_did)) = static_candidates.get(0)
+                && let Some(assoc) = self.associated_value(*impl_did, item_name)
+                && assoc.kind == ty::AssocKind::Fn
+            {
+                let sig = self.tcx.fn_sig(assoc.def_id);
+                if let Some(first) = sig.inputs().skip_binder().get(0) {
+                    if first.peel_refs() == rcvr_ty.peel_refs() {
+                        None
+                    } else {
+                        Some(if first.is_region_ptr() {
+                            if first.is_mutable_ptr() { "&mut " } else { "&" }
+                        } else {
+                            ""
+                        })
+                    }
+                } else {
+                    None
+                }
+            } else {
+                None
+            };
+            let mut applicability = Applicability::MachineApplicable;
+            let args = if let Some((receiver, args)) = args {
+                // The first arg is the same kind as the receiver
+                let explicit_args = if first_arg.is_some() {
+                    std::iter::once(receiver).chain(args.iter()).collect::<Vec<_>>()
+                } else {
+                    // There is no `Self` kind to infer the arguments from
+                    if has_unsuggestable_args {
+                        applicability = Applicability::HasPlaceholders;
+                    }
+                    args.iter().collect()
+                };
+                format!(
+                    "({}{})",
+                    first_arg.unwrap_or(""),
+                    explicit_args
+                        .iter()
+                        .map(|arg| self
+                            .tcx
+                            .sess
+                            .source_map()
+                            .span_to_snippet(arg.span)
+                            .unwrap_or_else(|_| {
+                                applicability = Applicability::HasPlaceholders;
+                                "_".to_owned()
+                            }))
+                        .collect::<Vec<_>>()
+                        .join(", "),
+                )
+            } else {
+                applicability = Applicability::HasPlaceholders;
+                "(...)".to_owned()
+            };
+            err.span_suggestion(
+                sugg_span,
+                "use associated function syntax instead",
+                format!("{}::{}{}", ty_str, item_name, args),
+                applicability,
+            );
+        } else {
+            err.help(&format!("try with `{}::{}`", ty_str, item_name,));
+        }
+    }
+
+    /// Suggest calling a field with a type that implements the `Fn*` traits instead of a method with
+    /// the same name as the field i.e. `(a.my_fn_ptr)(10)` instead of `a.my_fn_ptr(10)`.
+    fn suggest_calling_field_as_fn(
         &self,
         span: Span,
         rcvr_ty: Ty<'tcx>,
@@ -1407,7 +1468,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         false
     }
 
-    fn check_for_field_method(
+    /// Suggest calling a method on a field i.e. `a.field.bar()` instead of `a.bar()`
+    fn suggest_calling_method_on_field(
         &self,
         err: &mut Diagnostic,
         source: SelfSource<'tcx>,
@@ -1864,6 +1926,12 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         | ty::Str
                         | ty::Projection(_)
                         | ty::Param(_) => format!("{deref_ty}"),
+                        // we need to test something like  <&[_]>::len
+                        // and Vec::function();
+                        // <&[_]>::len doesn't need an extra "<>" between
+                        // but for Adt type like Vec::function()
+                        // we would suggest <[_]>::function();
+                        _ if self.tcx.sess.source_map().span_wrapped_by_angle_bracket(ty.span)  => format!("{deref_ty}"),
                         _ => format!("<{deref_ty}>"),
                     };
                     err.span_suggestion_verbose(
@@ -1886,7 +1954,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     /// Print out the type for use in value namespace.
     fn ty_to_value_string(&self, ty: Ty<'tcx>) -> String {
         match ty.kind() {
-            ty::Adt(def, substs) => format!("{}", ty::Instance::new(def.did(), substs)),
+            ty::Adt(def, substs) => self.tcx.def_path_str_with_substs(def.did(), substs),
             _ => self.ty_to_string(ty),
         }
     }
@@ -2015,11 +2083,15 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             Option<ty::Predicate<'tcx>>,
             Option<ObligationCause<'tcx>>,
         )],
+        static_candidates: &[CandidateSource],
         unsatisfied_bounds: bool,
     ) {
         let mut alt_rcvr_sugg = false;
         if let (SelfSource::MethodCall(rcvr), false) = (source, unsatisfied_bounds) {
-            debug!(?span, ?item_name, ?rcvr_ty, ?rcvr);
+            debug!(
+                "suggest_traits_to_import: span={:?}, item_name={:?}, rcvr_ty={:?}, rcvr={:?}",
+                span, item_name, rcvr_ty, rcvr
+            );
             let skippable = [
                 self.tcx.lang_items().clone_trait(),
                 self.tcx.lang_items().deref_trait(),
@@ -2058,7 +2130,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         // suggestions are generally misleading (see #94218).
                         break;
                     }
-                    _ => {}
+                    Err(_) => (),
                 }
 
                 for (rcvr_ty, pre) in &[
@@ -2128,6 +2200,16 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 Some(attr) => attr.level.is_stable(),
                 None => true,
             })
+            .filter(|info| {
+                // Static candidates are already implemented, and known not to work
+                // Do not suggest them again
+                static_candidates.iter().all(|sc| match *sc {
+                    CandidateSource::Trait(def_id) => def_id != info.def_id,
+                    CandidateSource::Impl(def_id) => {
+                        self.tcx.trait_id_of_impl(def_id) != Some(info.def_id)
+                    }
+                })
+            })
             .filter(|info| {
                 // We approximate the coherence rules to only suggest
                 // traits that are legal to implement by requiring that
diff --git a/compiler/rustc_hir_typeck/src/op.rs b/compiler/rustc_hir_typeck/src/op.rs
index 895739976938..38b3dd218a97 100644
--- a/compiler/rustc_hir_typeck/src/op.rs
+++ b/compiler/rustc_hir_typeck/src/op.rs
@@ -19,7 +19,7 @@ use rustc_span::symbol::{sym, Ident};
 use rustc_span::Span;
 use rustc_trait_selection::infer::InferCtxtExt;
 use rustc_trait_selection::traits::error_reporting::suggestions::TypeErrCtxtExt as _;
-use rustc_trait_selection::traits::{FulfillmentError, TraitEngine, TraitEngineExt};
+use rustc_trait_selection::traits::FulfillmentError;
 use rustc_type_ir::sty::TyKind::*;
 
 impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
@@ -529,8 +529,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         }
                     }
                 }
-                err.emit();
-                self.tcx.ty_error()
+                let reported = err.emit();
+                self.tcx.ty_error_with_guaranteed(reported)
             }
         };
 
@@ -772,7 +772,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         match (method, trait_did) {
             (Some(ok), _) => {
                 let method = self.register_infer_ok_obligations(ok);
-                self.select_obligations_where_possible(false, |_| {});
+                self.select_obligations_where_possible(|_| {});
                 Ok(method)
             }
             (None, None) => Err(vec![]),
@@ -785,9 +785,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     other_ty_expr,
                     expected,
                 );
-                let mut fulfill = <dyn TraitEngine<'_>>::new(self.tcx);
-                fulfill.register_predicate_obligation(self, obligation);
-                Err(fulfill.select_where_possible(&self.infcx))
+                Err(rustc_trait_selection::traits::fully_solve_obligation(self, obligation))
             }
         }
     }
diff --git a/compiler/rustc_hir_typeck/src/pat.rs b/compiler/rustc_hir_typeck/src/pat.rs
index ea90da4a6dc3..eb10f3e2c107 100644
--- a/compiler/rustc_hir_typeck/src/pat.rs
+++ b/compiler/rustc_hir_typeck/src/pat.rs
@@ -19,7 +19,6 @@ use rustc_span::lev_distance::find_best_match_for_name;
 use rustc_span::source_map::{Span, Spanned};
 use rustc_span::symbol::{kw, sym, Ident};
 use rustc_span::{BytePos, DUMMY_SP};
-use rustc_trait_selection::autoderef::Autoderef;
 use rustc_trait_selection::traits::{ObligationCause, Pattern};
 use ty::VariantDef;
 
@@ -1278,12 +1277,12 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         let element_tys = tcx.mk_type_list(element_tys_iter);
         let pat_ty = tcx.mk_ty(ty::Tuple(element_tys));
         if let Some(mut err) = self.demand_eqtype_pat_diag(span, expected, pat_ty, ti) {
-            err.emit();
+            let reported = err.emit();
             // Walk subpatterns with an expected type of `err` in this case to silence
             // further errors being emitted when using the bindings. #50333
-            let element_tys_iter = (0..max_len).map(|_| tcx.ty_error());
+            let element_tys_iter = (0..max_len).map(|_| tcx.ty_error_with_guaranteed(reported));
             for (_, elem) in elements.iter().enumerate_and_adjust(max_len, ddpos) {
-                self.check_pat(elem, tcx.ty_error(), def_bm, ti);
+                self.check_pat(elem, tcx.ty_error_with_guaranteed(reported), def_bm, ti);
             }
             tcx.mk_tup(element_tys_iter)
         } else {
@@ -2132,7 +2131,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             && let ty::Array(..) | ty::Slice(..) = ty.kind()
         {
             err.help("the semantics of slice patterns changed recently; see issue #62254");
-        } else if Autoderef::new(&self.infcx, self.param_env, self.body_id, span, expected_ty, span)
+        } else if self.autoderef(span, expected_ty)
             .any(|(ty, _)| matches!(ty.kind(), ty::Slice(..) | ty::Array(..)))
             && let (Some(span), true) = (ti.span, ti.origin_expr)
             && let Ok(snippet) = self.tcx.sess.source_map().span_to_snippet(span)
diff --git a/compiler/rustc_hir_typeck/src/place_op.rs b/compiler/rustc_hir_typeck/src/place_op.rs
index ba8cf6926f30..952ea14887f7 100644
--- a/compiler/rustc_hir_typeck/src/place_op.rs
+++ b/compiler/rustc_hir_typeck/src/place_op.rs
@@ -90,8 +90,11 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 Applicability::MachineApplicable,
             );
         }
-        err.emit();
-        Some((self.tcx.ty_error(), self.tcx.ty_error()))
+        let reported = err.emit();
+        Some((
+            self.tcx.ty_error_with_guaranteed(reported),
+            self.tcx.ty_error_with_guaranteed(reported),
+        ))
     }
 
     /// To type-check `base_expr[index_expr]`, we progressively autoderef
diff --git a/compiler/rustc_incremental/src/persist/dirty_clean.rs b/compiler/rustc_incremental/src/persist/dirty_clean.rs
index 9c19f16a496b..79e2d371ed37 100644
--- a/compiler/rustc_incremental/src/persist/dirty_clean.rs
+++ b/compiler/rustc_incremental/src/persist/dirty_clean.rs
@@ -149,19 +149,19 @@ pub fn check_dirty_clean_annotations(tcx: TyCtxt<'_>) {
         let crate_items = tcx.hir_crate_items(());
 
         for id in crate_items.items() {
-            dirty_clean_visitor.check_item(id.def_id.def_id);
+            dirty_clean_visitor.check_item(id.owner_id.def_id);
         }
 
         for id in crate_items.trait_items() {
-            dirty_clean_visitor.check_item(id.def_id.def_id);
+            dirty_clean_visitor.check_item(id.owner_id.def_id);
         }
 
         for id in crate_items.impl_items() {
-            dirty_clean_visitor.check_item(id.def_id.def_id);
+            dirty_clean_visitor.check_item(id.owner_id.def_id);
         }
 
         for id in crate_items.foreign_items() {
-            dirty_clean_visitor.check_item(id.def_id.def_id);
+            dirty_clean_visitor.check_item(id.owner_id.def_id);
         }
 
         let mut all_attrs = FindAllAttrs { tcx, found_attrs: vec![] };
diff --git a/compiler/rustc_infer/src/errors/mod.rs b/compiler/rustc_infer/src/errors/mod.rs
index 2131d19068e5..ec4eeb8caa27 100644
--- a/compiler/rustc_infer/src/errors/mod.rs
+++ b/compiler/rustc_infer/src/errors/mod.rs
@@ -109,8 +109,9 @@ pub struct InferenceBadError<'a> {
 
 #[derive(Subdiagnostic)]
 pub enum SourceKindSubdiag<'a> {
-    #[suggestion_verbose(
+    #[suggestion(
         infer_source_kind_subdiag_let,
+        style = "verbose",
         code = ": {type_name}",
         applicability = "has-placeholders"
     )]
@@ -135,8 +136,9 @@ pub enum SourceKindSubdiag<'a> {
         parent_prefix: String,
         parent_name: String,
     },
-    #[suggestion_verbose(
+    #[suggestion(
         infer_source_kind_subdiag_generic_suggestion,
+        style = "verbose",
         code = "::<{args}>",
         applicability = "has-placeholders"
     )]
@@ -150,8 +152,9 @@ pub enum SourceKindSubdiag<'a> {
 
 #[derive(Subdiagnostic)]
 pub enum SourceKindMultiSuggestion<'a> {
-    #[multipart_suggestion_verbose(
+    #[multipart_suggestion(
         infer_source_kind_fully_qualified,
+        style = "verbose",
         applicability = "has-placeholders"
     )]
     FullyQualified {
@@ -163,8 +166,9 @@ pub enum SourceKindMultiSuggestion<'a> {
         adjustment: &'a str,
         successor_pos: &'a str,
     },
-    #[multipart_suggestion_verbose(
+    #[multipart_suggestion(
         infer_source_kind_closure_return,
+        style = "verbose",
         applicability = "has-placeholders"
     )]
     ClosureReturn {
@@ -176,6 +180,18 @@ pub enum SourceKindMultiSuggestion<'a> {
     },
 }
 
+#[derive(Subdiagnostic)]
+#[suggestion(
+    infer_suggest_add_let_for_letchains,
+    style = "verbose",
+    applicability = "machine-applicable",
+    code = "let "
+)]
+pub(crate) struct SuggAddLetForLetChains {
+    #[primary_span]
+    pub span: Span,
+}
+
 impl<'a> SourceKindMultiSuggestion<'a> {
     pub fn new_fully_qualified(
         span: Span,
@@ -478,8 +494,9 @@ pub enum ImplicitStaticLifetimeSubdiag {
         #[primary_span]
         span: Span,
     },
-    #[suggestion_verbose(
+    #[suggestion(
         infer_implicit_static_lifetime_suggestion,
+        style = "verbose",
         code = " + '_",
         applicability = "maybe-incorrect"
     )]
diff --git a/compiler/rustc_infer/src/errors/note_and_explain.rs b/compiler/rustc_infer/src/errors/note_and_explain.rs
index 6a29d85627a8..7aaa5ce2f424 100644
--- a/compiler/rustc_infer/src/errors/note_and_explain.rs
+++ b/compiler/rustc_infer/src/errors/note_and_explain.rs
@@ -89,10 +89,13 @@ impl<'a> DescriptionCtx<'a> {
                             };
                             me.span = Some(sp);
                         }
-                        ty::BrAnon(idx) => {
+                        ty::BrAnon(idx, span) => {
                             me.kind = "anon_num_here";
                             me.num_arg = idx+1;
-                            me.span = Some(tcx.def_span(scope));
+                            me.span = match span {
+                                Some(_) => span,
+                                None => Some(tcx.def_span(scope)),
+                            }
                         },
                         _ => {
                             me.kind = "defined_here_reg";
diff --git a/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs b/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs
index a3ff70363403..3dc0d60b1eb0 100644
--- a/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs
+++ b/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs
@@ -495,7 +495,7 @@ impl<'cx, 'tcx> TypeFolder<'tcx> for Canonicalizer<'cx, 'tcx> {
             }
             ty::ConstKind::Bound(debruijn, _) => {
                 if debruijn >= self.binder_index {
-                    bug!("escaping bound type during canonicalization")
+                    bug!("escaping bound const during canonicalization")
                 } else {
                     return ct;
                 }
@@ -738,7 +738,7 @@ impl<'cx, 'tcx> Canonicalizer<'cx, 'tcx> {
         r: ty::Region<'tcx>,
     ) -> ty::Region<'tcx> {
         let var = self.canonical_var(info, r.into());
-        let br = ty::BoundRegion { var, kind: ty::BrAnon(var.as_u32()) };
+        let br = ty::BoundRegion { var, kind: ty::BrAnon(var.as_u32(), None) };
         let region = ty::ReLateBound(self.binder_index, br);
         self.tcx().mk_region(region)
     }
@@ -773,10 +773,10 @@ impl<'cx, 'tcx> Canonicalizer<'cx, 'tcx> {
             self.fold_const(bound_to)
         } else {
             let var = self.canonical_var(info, const_var.into());
-            self.tcx().mk_const(ty::ConstS {
-                kind: ty::ConstKind::Bound(self.binder_index, var),
-                ty: self.fold_ty(const_var.ty()),
-            })
+            self.tcx().mk_const(
+                ty::ConstKind::Bound(self.binder_index, var),
+                self.fold_ty(const_var.ty()),
+            )
         }
     }
 }
diff --git a/compiler/rustc_infer/src/infer/canonical/mod.rs b/compiler/rustc_infer/src/infer/canonical/mod.rs
index 06ca2534d5c3..0794792d8cb3 100644
--- a/compiler/rustc_infer/src/infer/canonical/mod.rs
+++ b/compiler/rustc_infer/src/infer/canonical/mod.rs
@@ -43,7 +43,7 @@ impl<'tcx> InferCtxt<'tcx> {
     ///
     /// This is only meant to be invoked as part of constructing an
     /// inference context at the start of a query (see
-    /// `InferCtxtBuilder::enter_with_canonical`). It basically
+    /// `InferCtxtBuilder::build_with_canonical`). It basically
     /// brings the canonical value "into scope" within your new infcx.
     ///
     /// At the end of processing, the substitution S (once
@@ -147,12 +147,7 @@ impl<'tcx> InferCtxt<'tcx> {
             CanonicalVarKind::PlaceholderConst(ty::PlaceholderConst { universe, name }, ty) => {
                 let universe_mapped = universe_map(universe);
                 let placeholder_mapped = ty::PlaceholderConst { universe: universe_mapped, name };
-                self.tcx
-                    .mk_const(ty::ConstS {
-                        kind: ty::ConstKind::Placeholder(placeholder_mapped),
-                        ty,
-                    })
-                    .into()
+                self.tcx.mk_const(ty::ConstKind::Placeholder(placeholder_mapped), ty).into()
             }
         }
     }
diff --git a/compiler/rustc_infer/src/infer/canonical/query_response.rs b/compiler/rustc_infer/src/infer/canonical/query_response.rs
index 608b5cc8756a..a299a3e578d2 100644
--- a/compiler/rustc_infer/src/infer/canonical/query_response.rs
+++ b/compiler/rustc_infer/src/infer/canonical/query_response.rs
@@ -16,8 +16,8 @@ use crate::infer::nll_relate::{NormalizationStrategy, TypeRelating, TypeRelating
 use crate::infer::region_constraints::{Constraint, RegionConstraintData};
 use crate::infer::{InferCtxt, InferOk, InferResult, NllRegionVariableOrigin};
 use crate::traits::query::{Fallible, NoSolution};
-use crate::traits::TraitEngine;
 use crate::traits::{Obligation, ObligationCause, PredicateObligation};
+use crate::traits::{PredicateObligations, TraitEngine};
 use rustc_data_structures::captures::Captures;
 use rustc_index::vec::Idx;
 use rustc_index::vec::IndexVec;
@@ -509,7 +509,7 @@ impl<'tcx> InferCtxt<'tcx> {
         for &(a, b) in &query_response.value.opaque_types {
             let a = substitute_value(self.tcx, &result_subst, a);
             let b = substitute_value(self.tcx, &result_subst, b);
-            obligations.extend(self.handle_opaque_type(a, b, true, cause, param_env)?.obligations);
+            obligations.extend(self.at(cause, param_env).eq(a, b)?.obligations);
         }
 
         Ok(InferOk { value: result_subst, obligations })
@@ -632,7 +632,7 @@ impl<'tcx> InferCtxt<'tcx> {
 /// creates query region constraints.
 pub fn make_query_region_constraints<'tcx>(
     tcx: TyCtxt<'tcx>,
-    outlives_obligations: impl Iterator<Item = (Ty<'tcx>, ty::Region<'tcx>, ConstraintCategory)>,
+    outlives_obligations: impl Iterator<Item = (Ty<'tcx>, ty::Region<'tcx>, ConstraintCategory<'tcx>)>,
     region_constraints: &RegionConstraintData<'tcx>,
 ) -> QueryRegionConstraints<'tcx> {
     let RegionConstraintData { constraints, verifys, givens, member_constraints } =
@@ -741,17 +741,11 @@ impl<'tcx> TypeRelatingDelegate<'tcx> for QueryTypeRelatingDelegate<'_, 'tcx> {
         true
     }
 
-    fn register_opaque_type(
+    fn register_opaque_type_obligations(
         &mut self,
-        a: Ty<'tcx>,
-        b: Ty<'tcx>,
-        a_is_expected: bool,
+        obligations: PredicateObligations<'tcx>,
     ) -> Result<(), TypeError<'tcx>> {
-        self.obligations.extend(
-            self.infcx
-                .handle_opaque_type(a, b, a_is_expected, &self.cause, self.param_env)?
-                .obligations,
-        );
+        self.obligations.extend(obligations);
         Ok(())
     }
 }
diff --git a/compiler/rustc_infer/src/infer/combine.rs b/compiler/rustc_infer/src/infer/combine.rs
index b5427f639c13..a973bf54b055 100644
--- a/compiler/rustc_infer/src/infer/combine.rs
+++ b/compiler/rustc_infer/src/infer/combine.rs
@@ -741,10 +741,10 @@ impl<'tcx> TypeRelation<'tcx> for Generalizer<'_, 'tcx> {
                     substs,
                     substs,
                 )?;
-                Ok(self.tcx().mk_const(ty::ConstS {
-                    ty: c.ty(),
-                    kind: ty::ConstKind::Unevaluated(ty::UnevaluatedConst { def, substs }),
-                }))
+                Ok(self.tcx().mk_const(
+                    ty::ConstKind::Unevaluated(ty::UnevaluatedConst { def, substs }),
+                    c.ty(),
+                ))
             }
             _ => relate::super_relate_consts(self, c, c),
         }
@@ -955,10 +955,10 @@ impl<'tcx> TypeRelation<'tcx> for ConstInferUnifier<'_, 'tcx> {
                     substs,
                 )?;
 
-                Ok(self.tcx().mk_const(ty::ConstS {
-                    ty: c.ty(),
-                    kind: ty::ConstKind::Unevaluated(ty::UnevaluatedConst { def, substs }),
-                }))
+                Ok(self.tcx().mk_const(
+                    ty::ConstKind::Unevaluated(ty::UnevaluatedConst { def, substs }),
+                    c.ty(),
+                ))
             }
             _ => relate::super_relate_consts(self, c, c),
         }
diff --git a/compiler/rustc_infer/src/infer/error_reporting/mod.rs b/compiler/rustc_infer/src/infer/error_reporting/mod.rs
index 9ff703e521ff..22f32251f6df 100644
--- a/compiler/rustc_infer/src/infer/error_reporting/mod.rs
+++ b/compiler/rustc_infer/src/infer/error_reporting/mod.rs
@@ -1,3 +1,4 @@
+// ignore-tidy-filelength
 //! Error Reporting Code for the inference engine
 //!
 //! Because of the way inference, and in particular region inference,
@@ -58,12 +59,15 @@ use crate::traits::{
     StatementAsExpression,
 };
 
-use rustc_data_structures::fx::{FxHashMap, FxHashSet};
+use crate::errors::SuggAddLetForLetChains;
+use hir::intravisit::{walk_expr, walk_stmt};
+use rustc_data_structures::fx::{FxIndexMap, FxIndexSet};
 use rustc_errors::{pluralize, struct_span_err, Diagnostic, ErrorGuaranteed, IntoDiagnosticArg};
 use rustc_errors::{Applicability, DiagnosticBuilder, DiagnosticStyledString, MultiSpan};
 use rustc_hir as hir;
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::{DefId, LocalDefId};
+use rustc_hir::intravisit::Visitor;
 use rustc_hir::lang_items::LangItem;
 use rustc_hir::Node;
 use rustc_middle::dep_graph::DepContext;
@@ -91,6 +95,7 @@ pub mod nice_region_error;
 pub struct TypeErrCtxt<'a, 'tcx> {
     pub infcx: &'a InferCtxt<'tcx>,
     pub typeck_results: Option<std::cell::Ref<'a, ty::TypeckResults<'tcx>>>,
+    pub fallback_has_occurred: bool,
 }
 
 impl TypeErrCtxt<'_, '_> {
@@ -206,9 +211,12 @@ fn msg_span_from_early_bound_and_free_regions<'tcx>(
                         };
                         (text, sp)
                     }
-                    ty::BrAnon(idx) => (
+                    ty::BrAnon(idx, span) => (
                         format!("the anonymous lifetime #{} defined here", idx + 1),
-                        tcx.def_span(scope)
+                        match span {
+                            Some(span) => span,
+                            None => tcx.def_span(scope)
+                        }
                     ),
                     _ => (
                         format!("the lifetime `{}` as defined here", region),
@@ -1498,9 +1506,9 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
             values = None;
         }
         struct OpaqueTypesVisitor<'tcx> {
-            types: FxHashMap<TyCategory, FxHashSet<Span>>,
-            expected: FxHashMap<TyCategory, FxHashSet<Span>>,
-            found: FxHashMap<TyCategory, FxHashSet<Span>>,
+            types: FxIndexMap<TyCategory, FxIndexSet<Span>>,
+            expected: FxIndexMap<TyCategory, FxIndexSet<Span>>,
+            found: FxIndexMap<TyCategory, FxIndexSet<Span>>,
             ignore_span: Span,
             tcx: TyCtxt<'tcx>,
         }
@@ -1538,7 +1546,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
                 &self,
                 err: &mut Diagnostic,
                 target: &str,
-                types: &FxHashMap<TyCategory, FxHashSet<Span>>,
+                types: &FxIndexMap<TyCategory, FxIndexSet<Span>>,
             ) {
                 for (key, values) in types.iter() {
                     let count = values.len();
@@ -2332,6 +2340,11 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
                                 }
                             }
                         }
+                        // For code `if Some(..) = expr `, the type mismatch may be expected `bool` but found `()`,
+                        // we try to suggest to add the missing `let` for `if let Some(..) = expr`
+                        (ty::Bool, ty::Tuple(list)) => if list.len() == 0 {
+                            self.suggest_let_for_letchains(&mut err, &trace.cause, span);
+                        }
                         _ => {}
                     }
                 }
@@ -2356,6 +2369,67 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
         diag
     }
 
+    /// Try to find code with pattern `if Some(..) = expr`
+    /// use a `visitor` to mark the `if` which its span contains given error span,
+    /// and then try to find a assignment in the `cond` part, which span is equal with error span
+    fn suggest_let_for_letchains(
+        &self,
+        err: &mut Diagnostic,
+        cause: &ObligationCause<'_>,
+        span: Span,
+    ) {
+        let hir = self.tcx.hir();
+        let fn_hir_id = hir.get_parent_node(cause.body_id);
+        if let Some(node) = self.tcx.hir().find(fn_hir_id) &&
+            let hir::Node::Item(hir::Item {
+                    kind: hir::ItemKind::Fn(_sig, _, body_id), ..
+                }) = node {
+        let body = hir.body(*body_id);
+
+        /// Find the if expression with given span
+        struct IfVisitor {
+            pub result: bool,
+            pub found_if: bool,
+            pub err_span: Span,
+        }
+
+        impl<'v> Visitor<'v> for IfVisitor {
+            fn visit_expr(&mut self, ex: &'v hir::Expr<'v>) {
+                if self.result { return; }
+                match ex.kind {
+                    hir::ExprKind::If(cond, _, _) => {
+                        self.found_if = true;
+                        walk_expr(self, cond);
+                        self.found_if = false;
+                    }
+                    _ => walk_expr(self, ex),
+                }
+            }
+
+            fn visit_stmt(&mut self, ex: &'v hir::Stmt<'v>) {
+                if let hir::StmtKind::Local(hir::Local {
+                        span, pat: hir::Pat{..}, ty: None, init: Some(_), ..
+                    }) = &ex.kind
+                    && self.found_if
+                    && span.eq(&self.err_span) {
+                        self.result = true;
+                }
+                walk_stmt(self, ex);
+            }
+
+            fn visit_body(&mut self, body: &'v hir::Body<'v>) {
+                hir::intravisit::walk_body(self, body);
+            }
+        }
+
+        let mut visitor = IfVisitor { err_span: span, found_if: false, result: false };
+        visitor.visit_body(&body);
+        if visitor.result {
+                err.subdiagnostic(SuggAddLetForLetChains{span: span.shrink_to_lo()});
+            }
+        }
+    }
+
     fn emit_tuple_wrap_err(
         &self,
         err: &mut Diagnostic,
@@ -3254,7 +3328,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
         if blk.expr.is_some() {
             return false;
         }
-        let mut shadowed = FxHashSet::default();
+        let mut shadowed = FxIndexSet::default();
         let mut candidate_idents = vec![];
         let mut find_compatible_candidates = |pat: &hir::Pat<'_>| {
             if let hir::PatKind::Binding(_, hir_id, ident, _) = &pat.kind
diff --git a/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/mismatched_static_lifetime.rs b/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/mismatched_static_lifetime.rs
index c5f2a1a3f7dc..1067ccda20ca 100644
--- a/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/mismatched_static_lifetime.rs
+++ b/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/mismatched_static_lifetime.rs
@@ -9,7 +9,7 @@ use crate::infer::error_reporting::nice_region_error::NiceRegionError;
 use crate::infer::lexical_region_resolve::RegionResolutionError;
 use crate::infer::{SubregionOrigin, TypeTrace};
 use crate::traits::ObligationCauseCode;
-use rustc_data_structures::fx::FxHashSet;
+use rustc_data_structures::fx::FxIndexSet;
 use rustc_errors::{ErrorGuaranteed, MultiSpan};
 use rustc_hir as hir;
 use rustc_hir::intravisit::Visitor;
@@ -73,7 +73,7 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> {
 
             // Next, let's figure out the set of trait objects with implicit static bounds
             let ty = self.tcx().type_of(*impl_def_id);
-            let mut v = super::static_impl_trait::TraitObjectVisitor(FxHashSet::default());
+            let mut v = super::static_impl_trait::TraitObjectVisitor(FxIndexSet::default());
             v.visit_ty(ty);
             let mut traits = vec![];
             for matching_def_id in v.0 {
diff --git a/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/mod.rs b/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/mod.rs
index aaf5a7af00af..8a0e332f9c70 100644
--- a/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/mod.rs
+++ b/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/mod.rs
@@ -10,6 +10,7 @@ pub mod find_anon_type;
 mod mismatched_static_lifetime;
 mod named_anon_conflict;
 mod placeholder_error;
+mod placeholder_relation;
 mod static_impl_trait;
 mod trait_impl_difference;
 mod util;
@@ -52,7 +53,9 @@ impl<'cx, 'tcx> NiceRegionError<'cx, 'tcx> {
     pub fn try_report_from_nll(&self) -> Option<DiagnosticBuilder<'tcx, ErrorGuaranteed>> {
         // Due to the improved diagnostics returned by the MIR borrow checker, only a subset of
         // the nice region errors are required when running under the MIR borrow checker.
-        self.try_report_named_anon_conflict().or_else(|| self.try_report_placeholder_conflict())
+        self.try_report_named_anon_conflict()
+            .or_else(|| self.try_report_placeholder_conflict())
+            .or_else(|| self.try_report_placeholder_relation())
     }
 
     pub fn try_report(&self) -> Option<ErrorGuaranteed> {
diff --git a/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/named_anon_conflict.rs b/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/named_anon_conflict.rs
index 76cb76d9ff4e..3fe7c1598fc3 100644
--- a/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/named_anon_conflict.rs
+++ b/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/named_anon_conflict.rs
@@ -68,7 +68,7 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> {
         let is_impl_item = region_info.is_impl_item;
 
         match br {
-            ty::BrNamed(_, kw::UnderscoreLifetime) | ty::BrAnon(_) => {}
+            ty::BrNamed(_, kw::UnderscoreLifetime) | ty::BrAnon(..) => {}
             _ => {
                 /* not an anonymous region */
                 debug!("try_report_named_anon_conflict: not an anonymous region");
diff --git a/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/placeholder_relation.rs b/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/placeholder_relation.rs
new file mode 100644
index 000000000000..c42240f21724
--- /dev/null
+++ b/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/placeholder_relation.rs
@@ -0,0 +1,79 @@
+use crate::infer::{
+    error_reporting::nice_region_error::NiceRegionError, RegionResolutionError, SubregionOrigin,
+};
+use rustc_data_structures::intern::Interned;
+use rustc_errors::{DiagnosticBuilder, ErrorGuaranteed};
+use rustc_middle::ty::{self, RePlaceholder, Region};
+
+impl<'tcx> NiceRegionError<'_, 'tcx> {
+    /// Emitted wwhen given a `ConcreteFailure` when relating two placeholders.
+    pub(super) fn try_report_placeholder_relation(
+        &self,
+    ) -> Option<DiagnosticBuilder<'tcx, ErrorGuaranteed>> {
+        match &self.error {
+            Some(RegionResolutionError::ConcreteFailure(
+                SubregionOrigin::RelateRegionParamBound(span),
+                Region(Interned(RePlaceholder(ty::Placeholder { name: sub_name, .. }), _)),
+                Region(Interned(RePlaceholder(ty::Placeholder { name: sup_name, .. }), _)),
+            )) => {
+                let msg = "lifetime bound not satisfied";
+                let mut err = self.tcx().sess.struct_span_err(*span, msg);
+                let (sub_span, sub_symbol) = match sub_name {
+                    ty::BrNamed(def_id, symbol) => {
+                        (Some(self.tcx().def_span(def_id)), Some(symbol))
+                    }
+                    ty::BrAnon(_, span) => (*span, None),
+                    ty::BrEnv => (None, None),
+                };
+                let (sup_span, sup_symbol) = match sup_name {
+                    ty::BrNamed(def_id, symbol) => {
+                        (Some(self.tcx().def_span(def_id)), Some(symbol))
+                    }
+                    ty::BrAnon(_, span) => (*span, None),
+                    ty::BrEnv => (None, None),
+                };
+                match (sub_span, sup_span, sub_symbol, sup_symbol) {
+                    (Some(sub_span), Some(sup_span), Some(sub_symbol), Some(sup_symbol)) => {
+                        err.span_note(
+                            sub_span,
+                            format!("the lifetime `{sub_symbol}` defined here..."),
+                        );
+                        err.span_note(
+                            sup_span,
+                            format!("...must outlive the lifetime `{sup_symbol}` defined here"),
+                        );
+                    }
+                    (Some(sub_span), Some(sup_span), _, Some(sup_symbol)) => {
+                        err.span_note(sub_span, format!("the lifetime defined here..."));
+                        err.span_note(
+                            sup_span,
+                            format!("...must outlive the lifetime `{sup_symbol}` defined here"),
+                        );
+                    }
+                    (Some(sub_span), Some(sup_span), Some(sub_symbol), _) => {
+                        err.span_note(
+                            sub_span,
+                            format!("the lifetime `{sub_symbol}` defined here..."),
+                        );
+                        err.span_note(
+                            sup_span,
+                            format!("...must outlive the lifetime defined here"),
+                        );
+                    }
+                    (Some(sub_span), Some(sup_span), _, _) => {
+                        err.span_note(sub_span, format!("the lifetime defined here..."));
+                        err.span_note(
+                            sup_span,
+                            format!("...must outlive the lifetime defined here"),
+                        );
+                    }
+                    _ => {}
+                }
+                err.note("this is a known limitation that will be removed in the future (see issue #100013 <https://github.com/rust-lang/rust/issues/100013> for more information)");
+                Some(err)
+            }
+
+            _ => None,
+        }
+    }
+}
diff --git a/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/static_impl_trait.rs b/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/static_impl_trait.rs
index 6bb736687d6e..b4efe8da1259 100644
--- a/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/static_impl_trait.rs
+++ b/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/static_impl_trait.rs
@@ -4,7 +4,7 @@ use crate::infer::error_reporting::nice_region_error::NiceRegionError;
 use crate::infer::lexical_region_resolve::RegionResolutionError;
 use crate::infer::{SubregionOrigin, TypeTrace};
 use crate::traits::{ObligationCauseCode, UnifyReceiverContext};
-use rustc_data_structures::fx::FxHashSet;
+use rustc_data_structures::fx::FxIndexSet;
 use rustc_errors::{struct_span_err, Applicability, Diagnostic, ErrorGuaranteed, MultiSpan};
 use rustc_hir::def_id::DefId;
 use rustc_hir::intravisit::{walk_ty, Visitor};
@@ -236,7 +236,7 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> {
             // Same case of `impl Foo for dyn Bar { fn qux(&self) {} }` introducing a `'static`
             // lifetime as above, but called using a fully-qualified path to the method:
             // `Foo::qux(bar)`.
-            let mut v = TraitObjectVisitor(FxHashSet::default());
+            let mut v = TraitObjectVisitor(FxIndexSet::default());
             v.visit_ty(param.param_ty);
             if let Some((ident, self_ty)) =
                 self.get_impl_ident_and_self_ty_from_trait(item_def_id, &v.0)
@@ -286,8 +286,8 @@ pub fn suggest_new_region_bound(
 ) {
     debug!("try_report_static_impl_trait: fn_return={:?}", fn_returns);
     // FIXME: account for the need of parens in `&(dyn Trait + '_)`
-    let consider = "consider changing the";
-    let declare = "to declare that the";
+    let consider = "consider changing";
+    let declare = "to declare that";
     let explicit = format!("you can add an explicit `{}` lifetime bound", lifetime_name);
     let explicit_static =
         arg.map(|arg| format!("explicit `'static` bound to the lifetime of {}", arg));
@@ -305,6 +305,10 @@ pub fn suggest_new_region_bound(
                     return;
                 };
 
+                // Get the identity type for this RPIT
+                let did = item_id.owner_id.to_def_id();
+                let ty = tcx.mk_opaque(did, ty::InternalSubsts::identity_for_item(tcx, did));
+
                 if let Some(span) = opaque
                     .bounds
                     .iter()
@@ -321,7 +325,7 @@ pub fn suggest_new_region_bound(
                     if let Some(explicit_static) = &explicit_static {
                         err.span_suggestion_verbose(
                             span,
-                            &format!("{} `impl Trait`'s {}", consider, explicit_static),
+                            &format!("{consider} `{ty}`'s {explicit_static}"),
                             &lifetime_name,
                             Applicability::MaybeIncorrect,
                         );
@@ -351,12 +355,7 @@ pub fn suggest_new_region_bound(
                 } else {
                     err.span_suggestion_verbose(
                         fn_return.span.shrink_to_hi(),
-                        &format!(
-                            "{declare} `impl Trait` {captures}, {explicit}",
-                            declare = declare,
-                            captures = captures,
-                            explicit = explicit,
-                        ),
+                        &format!("{declare} `{ty}` {captures}, {explicit}",),
                         &plus_lt,
                         Applicability::MaybeIncorrect,
                     );
@@ -367,7 +366,7 @@ pub fn suggest_new_region_bound(
                     err.span_suggestion_verbose(
                         fn_return.span.shrink_to_hi(),
                         &format!(
-                            "{declare} trait object {captures}, {explicit}",
+                            "{declare} the trait object {captures}, {explicit}",
                             declare = declare,
                             captures = captures,
                             explicit = explicit,
@@ -384,7 +383,7 @@ pub fn suggest_new_region_bound(
                     if let Some(explicit_static) = &explicit_static {
                         err.span_suggestion_verbose(
                             lt.span,
-                            &format!("{} trait object's {}", consider, explicit_static),
+                            &format!("{} the trait object's {}", consider, explicit_static),
                             &lifetime_name,
                             Applicability::MaybeIncorrect,
                         );
@@ -409,7 +408,7 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> {
     fn get_impl_ident_and_self_ty_from_trait(
         &self,
         def_id: DefId,
-        trait_objects: &FxHashSet<DefId>,
+        trait_objects: &FxIndexSet<DefId>,
     ) -> Option<(Ident, &'tcx hir::Ty<'tcx>)> {
         let tcx = self.tcx();
         match tcx.hir().get_if_local(def_id) {
@@ -491,7 +490,7 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> {
             return false;
         };
 
-        let mut v = TraitObjectVisitor(FxHashSet::default());
+        let mut v = TraitObjectVisitor(FxIndexSet::default());
         v.visit_ty(ty);
 
         // Get the `Ident` of the method being called and the corresponding `impl` (to point at
@@ -507,7 +506,7 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> {
     fn suggest_constrain_dyn_trait_in_impl(
         &self,
         err: &mut Diagnostic,
-        found_dids: &FxHashSet<DefId>,
+        found_dids: &FxIndexSet<DefId>,
         ident: Ident,
         self_ty: &hir::Ty<'_>,
     ) -> bool {
@@ -539,7 +538,7 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> {
 }
 
 /// Collect all the trait objects in a type that could have received an implicit `'static` lifetime.
-pub struct TraitObjectVisitor(pub FxHashSet<DefId>);
+pub struct TraitObjectVisitor(pub FxIndexSet<DefId>);
 
 impl<'tcx> TypeVisitor<'tcx> for TraitObjectVisitor {
     fn visit_ty(&mut self, t: Ty<'tcx>) -> ControlFlow<Self::BreakTy> {
diff --git a/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/util.rs b/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/util.rs
index f1461d7010d5..fd26d7d29c5e 100644
--- a/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/util.rs
+++ b/compiler/rustc_infer/src/infer/error_reporting/nice_region_error/util.rs
@@ -149,6 +149,8 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> {
         region: ty::BoundRegionKind,
     ) -> bool {
         let late_bound_regions = self.tcx().collect_referenced_late_bound_regions(&ty);
+        // We are only checking is any region meets the condition so order doesn't matter
+        #[allow(rustc::potential_query_instability)]
         late_bound_regions.iter().any(|r| *r == region)
     }
 
diff --git a/compiler/rustc_infer/src/infer/higher_ranked/mod.rs b/compiler/rustc_infer/src/infer/higher_ranked/mod.rs
index 28c87a1159f3..d739323de77c 100644
--- a/compiler/rustc_infer/src/infer/higher_ranked/mod.rs
+++ b/compiler/rustc_infer/src/infer/higher_ranked/mod.rs
@@ -94,13 +94,13 @@ impl<'tcx> InferCtxt<'tcx> {
                 }))
             },
             consts: &mut |bound_var: ty::BoundVar, ty| {
-                self.tcx.mk_const(ty::ConstS {
-                    kind: ty::ConstKind::Placeholder(ty::PlaceholderConst {
+                self.tcx.mk_const(
+                    ty::ConstKind::Placeholder(ty::PlaceholderConst {
                         universe: next_universe,
                         name: bound_var,
                     }),
                     ty,
-                })
+                )
             },
         };
 
diff --git a/compiler/rustc_infer/src/infer/lexical_region_resolve/mod.rs b/compiler/rustc_infer/src/infer/lexical_region_resolve/mod.rs
index 5f13b2b3deb1..ba990acfe6fc 100644
--- a/compiler/rustc_infer/src/infer/lexical_region_resolve/mod.rs
+++ b/compiler/rustc_infer/src/infer/lexical_region_resolve/mod.rs
@@ -842,6 +842,9 @@ impl<'cx, 'tcx> LexicalResolver<'cx, 'tcx> {
         // are placeholders as upper bounds, but the universe of the
         // variable `'a`, or some variable that `'a` has to outlive, doesn't
         // permit those placeholders.
+        //
+        // We only iterate to find the min, which means it doesn't cause reproducibility issues
+        #[allow(rustc::potential_query_instability)]
         let min_universe = lower_vid_bounds
             .into_iter()
             .map(|vid| self.var_infos[vid].universe)
diff --git a/compiler/rustc_infer/src/infer/mod.rs b/compiler/rustc_infer/src/infer/mod.rs
index 2732c92ecd38..fd3b3e4d59fa 100644
--- a/compiler/rustc_infer/src/infer/mod.rs
+++ b/compiler/rustc_infer/src/infer/mod.rs
@@ -10,6 +10,7 @@ pub(crate) use self::undo_log::{InferCtxtUndoLogs, Snapshot, UndoLog};
 
 use crate::traits::{self, ObligationCause, PredicateObligations, TraitEngine, TraitEngineExt};
 
+use rustc_data_structures::fx::FxIndexMap;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::sync::Lrc;
 use rustc_data_structures::undo_log::Rollback;
@@ -294,7 +295,7 @@ pub struct InferCtxt<'tcx> {
 
     /// the set of predicates on which errors have been reported, to
     /// avoid reporting the same error twice.
-    pub reported_trait_errors: RefCell<FxHashMap<Span, Vec<ty::Predicate<'tcx>>>>,
+    pub reported_trait_errors: RefCell<FxIndexMap<Span, Vec<ty::Predicate<'tcx>>>>,
 
     pub reported_closure_mismatch: RefCell<FxHashSet<(Span, Option<Span>)>>,
 
@@ -425,7 +426,7 @@ pub enum SubregionOrigin<'tcx> {
 static_assert_size!(SubregionOrigin<'_>, 32);
 
 impl<'tcx> SubregionOrigin<'tcx> {
-    pub fn to_constraint_category(&self) -> ConstraintCategory {
+    pub fn to_constraint_category(&self) -> ConstraintCategory<'tcx> {
         match self {
             Self::Subtype(type_trace) => type_trace.cause.to_constraint_category(),
             Self::AscribeUserTypeProvePredicate(span) => ConstraintCategory::Predicate(*span),
@@ -677,9 +678,9 @@ pub struct CombinedSnapshot<'tcx> {
 
 impl<'tcx> InferCtxt<'tcx> {
     /// Creates a `TypeErrCtxt` for emitting various inference errors.
-    /// During typeck, use `FnCtxt::infer_err` instead.
+    /// During typeck, use `FnCtxt::err_ctxt` instead.
     pub fn err_ctxt(&self) -> TypeErrCtxt<'_, 'tcx> {
-        TypeErrCtxt { infcx: self, typeck_results: None }
+        TypeErrCtxt { infcx: self, typeck_results: None, fallback_has_occurred: false }
     }
 
     /// calls `tcx.try_unify_abstract_consts` after
@@ -777,32 +778,6 @@ impl<'tcx> InferCtxt<'tcx> {
         }
     }
 
-    /// Clear the "currently in a snapshot" flag, invoke the closure,
-    /// then restore the flag to its original value. This flag is a
-    /// debugging measure designed to detect cases where we start a
-    /// snapshot, create type variables, and register obligations
-    /// which may involve those type variables in the fulfillment cx,
-    /// potentially leaving "dangling type variables" behind.
-    /// In such cases, an assertion will fail when attempting to
-    /// register obligations, within a snapshot. Very useful, much
-    /// better than grovelling through megabytes of `RUSTC_LOG` output.
-    ///
-    /// HOWEVER, in some cases the flag is unhelpful. In particular, we
-    /// sometimes create a "mini-fulfilment-cx" in which we enroll
-    /// obligations. As long as this fulfillment cx is fully drained
-    /// before we return, this is not a problem, as there won't be any
-    /// escaping obligations in the main cx. In those cases, you can
-    /// use this function.
-    pub fn save_and_restore_in_snapshot_flag<F, R>(&self, func: F) -> R
-    where
-        F: FnOnce(&Self) -> R,
-    {
-        let flag = self.in_snapshot.replace(false);
-        let result = func(self);
-        self.in_snapshot.set(flag);
-        result
-    }
-
     fn start_snapshot(&self) -> CombinedSnapshot<'tcx> {
         debug!("start_snapshot()");
 
@@ -1469,7 +1444,12 @@ impl<'tcx> InferCtxt<'tcx> {
          * except during the writeback phase.
          */
 
-        resolve::fully_resolve(self, value)
+        let value = resolve::fully_resolve(self, value);
+        assert!(
+            value.as_ref().map_or(true, |value| !value.needs_infer()),
+            "`{value:?}` is not fully resolved"
+        );
+        value
     }
 
     pub fn replace_bound_vars_with_fresh_vars<T>(
@@ -2060,13 +2040,13 @@ fn replace_param_and_infer_substs_with_placeholder<'tcx>(
                 if ty.has_non_region_param() || ty.has_non_region_infer() {
                     bug!("const `{ct}`'s type should not reference params or types");
                 }
-                tcx.mk_const(ty::ConstS {
-                    ty,
-                    kind: ty::ConstKind::Placeholder(ty::PlaceholderConst {
+                tcx.mk_const(
+                    ty::ConstKind::Placeholder(ty::PlaceholderConst {
                         universe: ty::UniverseIndex::ROOT,
                         name: ty::BoundVar::from_usize(idx),
                     }),
-                })
+                    ty,
+                )
                 .into()
             }
             _ => arg,
diff --git a/compiler/rustc_infer/src/infer/nll_relate/mod.rs b/compiler/rustc_infer/src/infer/nll_relate/mod.rs
index 7c186ae94706..600f94f095ea 100644
--- a/compiler/rustc_infer/src/infer/nll_relate/mod.rs
+++ b/compiler/rustc_infer/src/infer/nll_relate/mod.rs
@@ -25,7 +25,9 @@ use crate::infer::combine::ConstEquateRelation;
 use crate::infer::InferCtxt;
 use crate::infer::{ConstVarValue, ConstVariableValue};
 use crate::infer::{TypeVariableOrigin, TypeVariableOriginKind};
+use crate::traits::PredicateObligation;
 use rustc_data_structures::fx::FxHashMap;
+use rustc_middle::traits::ObligationCause;
 use rustc_middle::ty::error::TypeError;
 use rustc_middle::ty::relate::{self, Relate, RelateResult, TypeRelation};
 use rustc_middle::ty::visit::{TypeSuperVisitable, TypeVisitable, TypeVisitor};
@@ -91,11 +93,9 @@ pub trait TypeRelatingDelegate<'tcx> {
     );
 
     fn const_equate(&mut self, a: ty::Const<'tcx>, b: ty::Const<'tcx>);
-    fn register_opaque_type(
+    fn register_opaque_type_obligations(
         &mut self,
-        a: Ty<'tcx>,
-        b: Ty<'tcx>,
-        a_is_expected: bool,
+        obligations: Vec<PredicateObligation<'tcx>>,
     ) -> Result<(), TypeError<'tcx>>;
 
     /// Creates a new universe index. Used when instantiating placeholders.
@@ -414,7 +414,12 @@ where
             (_, &ty::Opaque(..)) => (generalize(a, true)?, b),
             _ => unreachable!(),
         };
-        self.delegate.register_opaque_type(a, b, true)?;
+        let cause = ObligationCause::dummy_with_span(self.delegate.span());
+        let obligations = self
+            .infcx
+            .handle_opaque_type(a, b, true, &cause, self.delegate.param_env())?
+            .obligations;
+        self.delegate.register_opaque_type_obligations(obligations)?;
         trace!(a = ?a.kind(), b = ?b.kind(), "opaque type instantiated");
         Ok(a)
     }
@@ -592,7 +597,7 @@ where
             (&ty::Infer(ty::TyVar(vid)), _) => self.relate_ty_var((vid, b)),
 
             (&ty::Opaque(a_def_id, _), &ty::Opaque(b_def_id, _)) if a_def_id == b_def_id => {
-                infcx.commit_if_ok(|_| infcx.super_combine_tys(self, a, b)).or_else(|err| {
+                infcx.super_combine_tys(self, a, b).or_else(|err| {
                     self.tcx().sess.delay_span_bug(
                         self.delegate.span(),
                         "failure to relate an opaque to itself should result in an error later on",
diff --git a/compiler/rustc_infer/src/infer/opaque_types.rs b/compiler/rustc_infer/src/infer/opaque_types.rs
index 0a4ecc4c033e..a982f11f7187 100644
--- a/compiler/rustc_infer/src/infer/opaque_types.rs
+++ b/compiler/rustc_infer/src/infer/opaque_types.rs
@@ -103,7 +103,7 @@ impl<'tcx> InferCtxt<'tcx> {
             return Ok(InferOk { value: (), obligations: vec![] });
         }
         let (a, b) = if a_is_expected { (a, b) } else { (b, a) };
-        let process = |a: Ty<'tcx>, b: Ty<'tcx>| match *a.kind() {
+        let process = |a: Ty<'tcx>, b: Ty<'tcx>, a_is_expected| match *a.kind() {
             ty::Opaque(def_id, substs) if def_id.is_local() => {
                 let def_id = def_id.expect_local();
                 let origin = match self.defining_use_anchor {
@@ -169,13 +169,14 @@ impl<'tcx> InferCtxt<'tcx> {
                     param_env,
                     b,
                     origin,
+                    a_is_expected,
                 ))
             }
             _ => None,
         };
-        if let Some(res) = process(a, b) {
+        if let Some(res) = process(a, b, true) {
             res
-        } else if let Some(res) = process(b, a) {
+        } else if let Some(res) = process(b, a, false) {
             res
         } else {
             let (a, b) = self.resolve_vars_if_possible((a, b));
@@ -514,13 +515,14 @@ impl UseKind {
 
 impl<'tcx> InferCtxt<'tcx> {
     #[instrument(skip(self), level = "debug")]
-    pub fn register_hidden_type(
+    fn register_hidden_type(
         &self,
         opaque_type_key: OpaqueTypeKey<'tcx>,
         cause: ObligationCause<'tcx>,
         param_env: ty::ParamEnv<'tcx>,
         hidden_ty: Ty<'tcx>,
         origin: hir::OpaqueTyOrigin,
+        a_is_expected: bool,
     ) -> InferResult<'tcx, ()> {
         let tcx = self.tcx;
         let OpaqueTypeKey { def_id, substs } = opaque_type_key;
@@ -539,7 +541,8 @@ impl<'tcx> InferCtxt<'tcx> {
             origin,
         );
         if let Some(prev) = prev {
-            obligations = self.at(&cause, param_env).eq(prev, hidden_ty)?.obligations;
+            obligations =
+                self.at(&cause, param_env).eq_exp(a_is_expected, prev, hidden_ty)?.obligations;
         }
 
         let item_bounds = tcx.bound_explicit_item_bounds(def_id.to_def_id());
diff --git a/compiler/rustc_infer/src/infer/outlives/obligations.rs b/compiler/rustc_infer/src/infer/outlives/obligations.rs
index 5ebf80b7b748..6ca884799aa6 100644
--- a/compiler/rustc_infer/src/infer/outlives/obligations.rs
+++ b/compiler/rustc_infer/src/infer/outlives/obligations.rs
@@ -210,7 +210,7 @@ pub trait TypeOutlivesDelegate<'tcx> {
         origin: SubregionOrigin<'tcx>,
         a: ty::Region<'tcx>,
         b: ty::Region<'tcx>,
-        constraint_category: ConstraintCategory,
+        constraint_category: ConstraintCategory<'tcx>,
     );
 
     fn push_verify(
@@ -259,7 +259,7 @@ where
         origin: infer::SubregionOrigin<'tcx>,
         ty: Ty<'tcx>,
         region: ty::Region<'tcx>,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
     ) {
         assert!(!ty.has_escaping_bound_vars());
 
@@ -273,7 +273,7 @@ where
         origin: infer::SubregionOrigin<'tcx>,
         components: &[Component<'tcx>],
         region: ty::Region<'tcx>,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
     ) {
         for component in components.iter() {
             let origin = origin.clone();
@@ -529,7 +529,7 @@ impl<'cx, 'tcx> TypeOutlivesDelegate<'tcx> for &'cx InferCtxt<'tcx> {
         origin: SubregionOrigin<'tcx>,
         a: ty::Region<'tcx>,
         b: ty::Region<'tcx>,
-        _constraint_category: ConstraintCategory,
+        _constraint_category: ConstraintCategory<'tcx>,
     ) {
         self.sub_regions(origin, a, b)
     }
diff --git a/compiler/rustc_infer/src/infer/region_constraints/leak_check.rs b/compiler/rustc_infer/src/infer/region_constraints/leak_check.rs
index 90858e3072ac..22b4bbb17d47 100644
--- a/compiler/rustc_infer/src/infer/region_constraints/leak_check.rs
+++ b/compiler/rustc_infer/src/infer/region_constraints/leak_check.rs
@@ -1,6 +1,7 @@
 use super::*;
 use crate::infer::CombinedSnapshot;
 use rustc_data_structures::{
+    fx::FxIndexMap,
     graph::{scc::Sccs, vec_graph::VecGraph},
     undo_log::UndoLogs,
 };
@@ -371,7 +372,7 @@ rustc_index::newtype_index! {
 /// an edge `R1 -> R2` in the graph.
 struct MiniGraph<'tcx> {
     /// Map from a region to the index of the node in the graph.
-    nodes: FxHashMap<ty::Region<'tcx>, LeakCheckNode>,
+    nodes: FxIndexMap<ty::Region<'tcx>, LeakCheckNode>,
 
     /// Map from node index to SCC, and stores the successors of each SCC. All
     /// the regions in the same SCC are equal to one another, and if `S1 -> S2`,
@@ -388,7 +389,7 @@ impl<'tcx> MiniGraph<'tcx> {
     where
         'tcx: 'a,
     {
-        let mut nodes = FxHashMap::default();
+        let mut nodes = FxIndexMap::default();
         let mut edges = Vec::new();
 
         // Note that if `R2: R1`, we get a callback `r1, r2`, so `target` is first parameter.
@@ -438,7 +439,7 @@ impl<'tcx> MiniGraph<'tcx> {
     }
 
     fn add_node(
-        nodes: &mut FxHashMap<ty::Region<'tcx>, LeakCheckNode>,
+        nodes: &mut FxIndexMap<ty::Region<'tcx>, LeakCheckNode>,
         r: ty::Region<'tcx>,
     ) -> LeakCheckNode {
         let l = nodes.len();
diff --git a/compiler/rustc_infer/src/infer/region_constraints/mod.rs b/compiler/rustc_infer/src/infer/region_constraints/mod.rs
index 67b3da687200..985c5d360db8 100644
--- a/compiler/rustc_infer/src/infer/region_constraints/mod.rs
+++ b/compiler/rustc_infer/src/infer/region_constraints/mod.rs
@@ -7,7 +7,7 @@ use super::{
     InferCtxtUndoLogs, MiscVariable, RegionVariableOrigin, Rollback, Snapshot, SubregionOrigin,
 };
 
-use rustc_data_structures::fx::{FxHashMap, FxHashSet};
+use rustc_data_structures::fx::{FxHashMap, FxIndexSet};
 use rustc_data_structures::intern::Interned;
 use rustc_data_structures::sync::Lrc;
 use rustc_data_structures::undo_log::UndoLogs;
@@ -125,7 +125,7 @@ pub struct RegionConstraintData<'tcx> {
     /// we record the fact that `'a <= 'b` is implied by the fn
     /// signature, and then ignore the constraint when solving
     /// equations. This is a bit of a hack but seems to work.
-    pub givens: FxHashSet<(Region<'tcx>, ty::RegionVid)>,
+    pub givens: FxIndexSet<(Region<'tcx>, ty::RegionVid)>,
 }
 
 /// Represents a constraint that influences the inference process.
diff --git a/compiler/rustc_infer/src/infer/sub.rs b/compiler/rustc_infer/src/infer/sub.rs
index a4b55dfa691d..97354ba5d1bd 100644
--- a/compiler/rustc_infer/src/infer/sub.rs
+++ b/compiler/rustc_infer/src/infer/sub.rs
@@ -2,9 +2,7 @@ use super::combine::{CombineFields, RelationDir};
 use super::SubregionOrigin;
 
 use crate::infer::combine::ConstEquateRelation;
-use crate::infer::{TypeVariableOrigin, TypeVariableOriginKind};
 use crate::traits::Obligation;
-use rustc_middle::ty::error::{ExpectedFound, TypeError};
 use rustc_middle::ty::relate::{Cause, Relate, RelateResult, TypeRelation};
 use rustc_middle::ty::visit::TypeVisitable;
 use rustc_middle::ty::TyVar;
@@ -130,39 +128,18 @@ impl<'tcx> TypeRelation<'tcx> for Sub<'_, '_, 'tcx> {
             (&ty::Opaque(did, ..), _) | (_, &ty::Opaque(did, ..))
                 if self.fields.define_opaque_types && did.is_local() =>
             {
-                let mut generalize = |ty, ty_is_expected| {
-                    let var = infcx.next_ty_var_id_in_universe(
-                        TypeVariableOrigin {
-                            kind: TypeVariableOriginKind::MiscVariable,
-                            span: self.fields.trace.cause.span,
-                        },
-                        ty::UniverseIndex::ROOT,
-                    );
-                    self.fields.instantiate(ty, RelationDir::SubtypeOf, var, ty_is_expected)?;
-                    Ok(infcx.tcx.mk_ty_var(var))
-                };
-                let (a, b) = if self.a_is_expected { (a, b) } else { (b, a) };
-                let (ga, gb) = match (a.kind(), b.kind()) {
-                    (&ty::Opaque(..), _) => (a, generalize(b, true)?),
-                    (_, &ty::Opaque(..)) => (generalize(a, false)?, b),
-                    _ => unreachable!(),
-                };
                 self.fields.obligations.extend(
                     infcx
-                        .handle_opaque_type(ga, gb, true, &self.fields.trace.cause, self.param_env())
-                        // Don't leak any generalized type variables out of this
-                        // subtyping relation in the case of a type error.
-                        .map_err(|err| {
-                            let (ga, gb) = self.fields.infcx.resolve_vars_if_possible((ga, gb));
-                            if let TypeError::Sorts(sorts) = err && sorts.expected == ga && sorts.found == gb {
-                                TypeError::Sorts(ExpectedFound { expected: a, found: b })
-                            } else {
-                                err
-                            }
-                        })?
+                        .handle_opaque_type(
+                            a,
+                            b,
+                            self.a_is_expected,
+                            &self.fields.trace.cause,
+                            self.param_env(),
+                        )?
                         .obligations,
                 );
-                Ok(ga)
+                Ok(a)
             }
             // Optimization of GeneratorWitness relation since we know that all
             // free regions are replaced with bound regions during construction.
diff --git a/compiler/rustc_infer/src/lib.rs b/compiler/rustc_infer/src/lib.rs
index e040634edb08..4c119a443555 100644
--- a/compiler/rustc_infer/src/lib.rs
+++ b/compiler/rustc_infer/src/lib.rs
@@ -12,7 +12,6 @@
 //!
 //! This API is completely unstable and subject to change.
 
-#![allow(rustc::potential_query_instability)]
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
 #![feature(box_patterns)]
 #![feature(control_flow_enum)]
diff --git a/compiler/rustc_infer/src/traits/error_reporting/mod.rs b/compiler/rustc_infer/src/traits/error_reporting/mod.rs
index f8b5009a58d4..4d53519581b3 100644
--- a/compiler/rustc_infer/src/traits/error_reporting/mod.rs
+++ b/compiler/rustc_infer/src/traits/error_reporting/mod.rs
@@ -1,7 +1,7 @@
 use super::ObjectSafetyViolation;
 
 use crate::infer::InferCtxt;
-use rustc_data_structures::fx::FxHashSet;
+use rustc_data_structures::fx::FxIndexSet;
 use rustc_errors::{struct_span_err, DiagnosticBuilder, ErrorGuaranteed, MultiSpan};
 use rustc_hir as hir;
 use rustc_hir::def_id::{DefId, LocalDefId};
@@ -56,7 +56,7 @@ pub fn report_object_safety_error<'tcx>(
     );
     err.span_label(span, format!("`{}` cannot be made into an object", trait_str));
 
-    let mut reported_violations = FxHashSet::default();
+    let mut reported_violations = FxIndexSet::default();
     let mut multi_span = vec![];
     let mut messages = vec![];
     for violation in violations {
diff --git a/compiler/rustc_interface/Cargo.toml b/compiler/rustc_interface/Cargo.toml
index 6a4c5b4d3737..2e526733df97 100644
--- a/compiler/rustc_interface/Cargo.toml
+++ b/compiler/rustc_interface/Cargo.toml
@@ -48,12 +48,6 @@ rustc_resolve = { path = "../rustc_resolve" }
 rustc_trait_selection = { path = "../rustc_trait_selection" }
 rustc_ty_utils = { path = "../rustc_ty_utils" }
 
-[target.'cfg(unix)'.dependencies]
-libc = "0.2"
-
-[target.'cfg(windows)'.dependencies]
-winapi = { version = "0.3", features = ["libloaderapi"] }
-
 [dev-dependencies]
 rustc_target = { path = "../rustc_target" }
 
diff --git a/compiler/rustc_interface/src/lib.rs b/compiler/rustc_interface/src/lib.rs
index a41a749ee68e..542b638bbd7a 100644
--- a/compiler/rustc_interface/src/lib.rs
+++ b/compiler/rustc_interface/src/lib.rs
@@ -1,4 +1,5 @@
 #![feature(box_patterns)]
+#![feature(decl_macro)]
 #![feature(internal_output_capture)]
 #![feature(thread_spawn_unchecked)]
 #![feature(once_cell)]
diff --git a/compiler/rustc_interface/src/passes.rs b/compiler/rustc_interface/src/passes.rs
index a47c3e3253ec..7f1d21bf1d8b 100644
--- a/compiler/rustc_interface/src/passes.rs
+++ b/compiler/rustc_interface/src/passes.rs
@@ -16,7 +16,6 @@ use rustc_data_structures::sync::{Lrc, OnceCell, WorkerLocal};
 use rustc_errors::{ErrorGuaranteed, PResult};
 use rustc_expand::base::{ExtCtxt, LintStoreExpand, ResolverExpand};
 use rustc_hir::def_id::StableCrateId;
-use rustc_hir::definitions::Definitions;
 use rustc_lint::{BufferedEarlyLint, EarlyCheckNode, LintStore};
 use rustc_metadata::creader::CStore;
 use rustc_middle::arena::Arena;
@@ -30,7 +29,7 @@ use rustc_plugin_impl as plugin;
 use rustc_query_impl::{OnDiskCache, Queries as TcxQueries};
 use rustc_resolve::{Resolver, ResolverArenas};
 use rustc_session::config::{CrateType, Input, OutputFilenames, OutputType};
-use rustc_session::cstore::{CrateStoreDyn, MetadataLoader, MetadataLoaderDyn};
+use rustc_session::cstore::{MetadataLoader, MetadataLoaderDyn};
 use rustc_session::output::filename_for_input;
 use rustc_session::search_paths::PathKind;
 use rustc_session::{Limit, Session};
@@ -135,10 +134,7 @@ mod boxed_resolver {
             f((&mut *resolver).as_mut().unwrap())
         }
 
-        pub fn to_resolver_outputs(
-            resolver: Rc<RefCell<BoxedResolver>>,
-        ) -> (Definitions, Box<CrateStoreDyn>, ty::ResolverOutputs, ty::ResolverAstLowering)
-        {
+        pub fn to_resolver_outputs(resolver: Rc<RefCell<BoxedResolver>>) -> ty::ResolverOutputs {
             match Rc::try_unwrap(resolver) {
                 Ok(resolver) => {
                     let mut resolver = resolver.into_inner();
@@ -788,8 +784,7 @@ pub fn create_global_ctxt<'tcx>(
     // incr. comp. yet.
     dep_graph.assert_ignored();
 
-    let (definitions, cstore, resolver_outputs, resolver_for_lowering) =
-        BoxedResolver::to_resolver_outputs(resolver);
+    let resolver_outputs = BoxedResolver::to_resolver_outputs(resolver);
 
     let sess = &compiler.session();
     let query_result_on_disk_cache = rustc_incremental::load_query_result_cache(sess);
@@ -816,10 +811,7 @@ pub fn create_global_ctxt<'tcx>(
                 lint_store,
                 arena,
                 hir_arena,
-                definitions,
-                cstore,
                 resolver_outputs,
-                resolver_for_lowering,
                 krate,
                 dep_graph,
                 queries.on_disk_cache.as_ref().map(OnDiskCache::as_dyn),
@@ -935,7 +927,7 @@ fn analysis(tcx: TyCtxt<'_>, (): ()) -> Result<()> {
     sess.time("misc_checking_3", || {
         parallel!(
             {
-                tcx.ensure().privacy_access_levels(());
+                tcx.ensure().effective_visibilities(());
 
                 parallel!(
                     {
diff --git a/compiler/rustc_interface/src/proc_macro_decls.rs b/compiler/rustc_interface/src/proc_macro_decls.rs
index 2b1b931b7326..9bf7778bfb29 100644
--- a/compiler/rustc_interface/src/proc_macro_decls.rs
+++ b/compiler/rustc_interface/src/proc_macro_decls.rs
@@ -4,21 +4,16 @@ use rustc_middle::ty::TyCtxt;
 use rustc_span::symbol::sym;
 
 fn proc_macro_decls_static(tcx: TyCtxt<'_>, (): ()) -> Option<LocalDefId> {
-    let mut finder = Finder { tcx, decls: None };
+    let mut decls = None;
 
     for id in tcx.hir().items() {
-        let attrs = finder.tcx.hir().attrs(id.hir_id());
-        if finder.tcx.sess.contains_name(attrs, sym::rustc_proc_macro_decls) {
-            finder.decls = Some(id.def_id.def_id);
+        let attrs = tcx.hir().attrs(id.hir_id());
+        if tcx.sess.contains_name(attrs, sym::rustc_proc_macro_decls) {
+            decls = Some(id.owner_id.def_id);
         }
     }
 
-    finder.decls
-}
-
-struct Finder<'tcx> {
-    tcx: TyCtxt<'tcx>,
-    decls: Option<LocalDefId>,
+    decls
 }
 
 pub(crate) fn provide(providers: &mut Providers) {
diff --git a/compiler/rustc_interface/src/tests.rs b/compiler/rustc_interface/src/tests.rs
index eb8e65a6d59d..a03e7b0dae52 100644
--- a/compiler/rustc_interface/src/tests.rs
+++ b/compiler/rustc_interface/src/tests.rs
@@ -690,6 +690,7 @@ fn test_unstable_options_tracking_hash() {
     untracked!(time_llvm_passes, true);
     untracked!(time_passes, true);
     untracked!(trace_macros, true);
+    untracked!(track_diagnostics, true);
     untracked!(trim_diagnostic_paths, false);
     untracked!(ui_testing, true);
     untracked!(unpretty, Some("expanded".to_string()));
diff --git a/compiler/rustc_interface/src/util.rs b/compiler/rustc_interface/src/util.rs
index 519b8a7fc7c3..2fe3fb2fa566 100644
--- a/compiler/rustc_interface/src/util.rs
+++ b/compiler/rustc_interface/src/util.rs
@@ -9,6 +9,7 @@ use rustc_session as session;
 use rustc_session::config::CheckCfg;
 use rustc_session::config::{self, CrateType};
 use rustc_session::config::{ErrorOutputType, Input, OutputFilenames};
+use rustc_session::filesearch::sysroot_candidates;
 use rustc_session::lint::{self, BuiltinLintDiagnostics, LintBuffer};
 use rustc_session::parse::CrateConfig;
 use rustc_session::{early_error, filesearch, output, Session};
@@ -78,7 +79,7 @@ pub fn create_session(
 
     let bundle = match rustc_errors::fluent_bundle(
         sopts.maybe_sysroot.clone(),
-        sysroot_candidates(),
+        sysroot_candidates().to_vec(),
         sopts.unstable_opts.translate_lang.clone(),
         sopts.unstable_opts.translate_additional_ftl.as_deref(),
         sopts.unstable_opts.translate_directionality_markers,
@@ -273,100 +274,6 @@ fn get_rustc_path_inner(bin_path: &str) -> Option<PathBuf> {
     })
 }
 
-fn sysroot_candidates() -> Vec<PathBuf> {
-    let target = session::config::host_triple();
-    let mut sysroot_candidates = vec![filesearch::get_or_default_sysroot()];
-    let path = current_dll_path().and_then(|s| s.canonicalize().ok());
-    if let Some(dll) = path {
-        // use `parent` twice to chop off the file name and then also the
-        // directory containing the dll which should be either `lib` or `bin`.
-        if let Some(path) = dll.parent().and_then(|p| p.parent()) {
-            // The original `path` pointed at the `rustc_driver` crate's dll.
-            // Now that dll should only be in one of two locations. The first is
-            // in the compiler's libdir, for example `$sysroot/lib/*.dll`. The
-            // other is the target's libdir, for example
-            // `$sysroot/lib/rustlib/$target/lib/*.dll`.
-            //
-            // We don't know which, so let's assume that if our `path` above
-            // ends in `$target` we *could* be in the target libdir, and always
-            // assume that we may be in the main libdir.
-            sysroot_candidates.push(path.to_owned());
-
-            if path.ends_with(target) {
-                sysroot_candidates.extend(
-                    path.parent() // chop off `$target`
-                        .and_then(|p| p.parent()) // chop off `rustlib`
-                        .and_then(|p| p.parent()) // chop off `lib`
-                        .map(|s| s.to_owned()),
-                );
-            }
-        }
-    }
-
-    return sysroot_candidates;
-
-    #[cfg(unix)]
-    fn current_dll_path() -> Option<PathBuf> {
-        use std::ffi::{CStr, OsStr};
-        use std::os::unix::prelude::*;
-
-        unsafe {
-            let addr = current_dll_path as usize as *mut _;
-            let mut info = mem::zeroed();
-            if libc::dladdr(addr, &mut info) == 0 {
-                info!("dladdr failed");
-                return None;
-            }
-            if info.dli_fname.is_null() {
-                info!("dladdr returned null pointer");
-                return None;
-            }
-            let bytes = CStr::from_ptr(info.dli_fname).to_bytes();
-            let os = OsStr::from_bytes(bytes);
-            Some(PathBuf::from(os))
-        }
-    }
-
-    #[cfg(windows)]
-    fn current_dll_path() -> Option<PathBuf> {
-        use std::ffi::OsString;
-        use std::io;
-        use std::os::windows::prelude::*;
-        use std::ptr;
-
-        use winapi::um::libloaderapi::{
-            GetModuleFileNameW, GetModuleHandleExW, GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS,
-        };
-
-        unsafe {
-            let mut module = ptr::null_mut();
-            let r = GetModuleHandleExW(
-                GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS,
-                current_dll_path as usize as *mut _,
-                &mut module,
-            );
-            if r == 0 {
-                info!("GetModuleHandleExW failed: {}", io::Error::last_os_error());
-                return None;
-            }
-            let mut space = Vec::with_capacity(1024);
-            let r = GetModuleFileNameW(module, space.as_mut_ptr(), space.capacity() as u32);
-            if r == 0 {
-                info!("GetModuleFileNameW failed: {}", io::Error::last_os_error());
-                return None;
-            }
-            let r = r as usize;
-            if r >= space.capacity() {
-                info!("our buffer was too small? {}", io::Error::last_os_error());
-                return None;
-            }
-            space.set_len(r);
-            let os = OsString::from_wide(&space);
-            Some(PathBuf::from(os))
-        }
-    }
-}
-
 fn get_codegen_sysroot(maybe_sysroot: &Option<PathBuf>, backend_name: &str) -> MakeBackendFn {
     // For now we only allow this function to be called once as it'll dlopen a
     // few things, which seems to work best if we only do that once. In
@@ -420,7 +327,7 @@ fn get_codegen_sysroot(maybe_sysroot: &Option<PathBuf>, backend_name: &str) -> M
     let mut file: Option<PathBuf> = None;
 
     let expected_names = &[
-        format!("rustc_codegen_{}-{}", backend_name, release_str().expect("CFG_RELEASE")),
+        format!("rustc_codegen_{}-{}", backend_name, env!("CFG_RELEASE")),
         format!("rustc_codegen_{}", backend_name),
     ];
     for entry in d.filter_map(|e| e.ok()) {
@@ -647,22 +554,12 @@ pub fn build_output_filenames(
     }
 }
 
-/// Returns a version string such as "1.46.0 (04488afe3 2020-08-24)"
-pub fn version_str() -> Option<&'static str> {
+/// Returns a version string such as "1.46.0 (04488afe3 2020-08-24)" when invoked by an in-tree tool.
+pub macro version_str() {
     option_env!("CFG_VERSION")
 }
 
-/// Returns a version string such as "0.12.0-dev".
-pub fn release_str() -> Option<&'static str> {
-    option_env!("CFG_RELEASE")
-}
-
-/// Returns the full SHA1 hash of HEAD of the Git repo from which rustc was built.
-pub fn commit_hash_str() -> Option<&'static str> {
-    option_env!("CFG_VER_HASH")
-}
-
-/// Returns the "commit date" of HEAD of the Git repo from which rustc was built as a static string.
-pub fn commit_date_str() -> Option<&'static str> {
-    option_env!("CFG_VER_DATE")
+/// Returns the version string for `rustc` itself (which may be different from a tool version).
+pub fn rustc_version_str() -> Option<&'static str> {
+    version_str!()
 }
diff --git a/compiler/rustc_lexer/src/lib.rs b/compiler/rustc_lexer/src/lib.rs
index c71e6ffe34d9..d4140cb295f3 100644
--- a/compiler/rustc_lexer/src/lib.rs
+++ b/compiler/rustc_lexer/src/lib.rs
@@ -57,29 +57,44 @@ pub enum TokenKind {
     // Multi-char tokens:
     /// "// comment"
     LineComment { doc_style: Option<DocStyle> },
+
     /// `/* block comment */`
     ///
-    /// Block comments can be recursive, so the sequence like `/* /* */`
+    /// Block comments can be recursive, so a sequence like `/* /* */`
     /// will not be considered terminated and will result in a parsing error.
     BlockComment { doc_style: Option<DocStyle>, terminated: bool },
-    /// Any whitespace characters sequence.
+
+    /// Any whitespace character sequence.
     Whitespace,
+
     /// "ident" or "continue"
-    /// At this step keywords are also considered identifiers.
+    ///
+    /// At this step, keywords are also considered identifiers.
     Ident,
+
     /// Like the above, but containing invalid unicode codepoints.
     InvalidIdent,
+
     /// "r#ident"
     RawIdent,
-    /// An unknown prefix like `foo#`, `foo'`, `foo"`. Note that only the
+
+    /// An unknown prefix, like `foo#`, `foo'`, `foo"`.
+    ///
+    /// Note that only the
     /// prefix (`foo`) is included in the token, not the separator (which is
     /// lexed as its own distinct token). In Rust 2021 and later, reserved
     /// prefixes are reported as errors; in earlier editions, they result in a
     /// (allowed by default) lint, and are treated as regular identifier
     /// tokens.
     UnknownPrefix,
-    /// "12_u8", "1.0e-40", "b"123"". See `LiteralKind` for more details.
+
+    /// Examples: `12u8`, `1.0e-40`, `b"123"`. Note that `_` is an invalid
+    /// suffix, but may be present here on string and float literals. Users of
+    /// this type will need to check for and reject that case.
+    ///
+    /// See [LiteralKind] for more details.
     Literal { kind: LiteralKind, suffix_start: u32 },
+
     /// "'a"
     Lifetime { starts_with_number: bool },
 
@@ -190,13 +205,13 @@ pub enum RawStrError {
 #[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord)]
 pub enum Base {
     /// Literal starts with "0b".
-    Binary,
+    Binary = 2,
     /// Literal starts with "0o".
-    Octal,
-    /// Literal starts with "0x".
-    Hexadecimal,
+    Octal = 8,
     /// Literal doesn't contain a prefix.
-    Decimal,
+    Decimal = 10,
+    /// Literal starts with "0x".
+    Hexadecimal = 16,
 }
 
 /// `rustc` allows files to have a shebang, e.g. "#!/usr/bin/rustrun",
@@ -827,12 +842,13 @@ impl Cursor<'_> {
         self.eat_decimal_digits()
     }
 
-    // Eats the suffix of the literal, e.g. "_u8".
+    // Eats the suffix of the literal, e.g. "u8".
     fn eat_literal_suffix(&mut self) {
         self.eat_identifier();
     }
 
-    // Eats the identifier.
+    // Eats the identifier. Note: succeeds on `_`, which isn't a valid
+    // identifer.
     fn eat_identifier(&mut self) {
         if !is_id_start(self.first()) {
             return;
diff --git a/compiler/rustc_lexer/src/unescape.rs b/compiler/rustc_lexer/src/unescape.rs
index 8f64b5f5158e..e405013dcabf 100644
--- a/compiler/rustc_lexer/src/unescape.rs
+++ b/compiler/rustc_lexer/src/unescape.rs
@@ -52,10 +52,8 @@ pub enum EscapeError {
 
     /// Unicode escape code in byte literal.
     UnicodeEscapeInByte,
-    /// Non-ascii character in byte literal.
+    /// Non-ascii character in byte literal, byte string literal, or raw byte string literal.
     NonAsciiCharInByte,
-    /// Non-ascii character in byte string literal.
-    NonAsciiCharInByteString,
 
     /// After a line ending with '\', the next line contains whitespace
     /// characters that are not skipped.
@@ -78,54 +76,33 @@ impl EscapeError {
 /// Takes a contents of a literal (without quotes) and produces a
 /// sequence of escaped characters or errors.
 /// Values are returned through invoking of the provided callback.
-pub fn unescape_literal<F>(literal_text: &str, mode: Mode, callback: &mut F)
+pub fn unescape_literal<F>(src: &str, mode: Mode, callback: &mut F)
 where
     F: FnMut(Range<usize>, Result<char, EscapeError>),
 {
     match mode {
         Mode::Char | Mode::Byte => {
-            let mut chars = literal_text.chars();
-            let result = unescape_char_or_byte(&mut chars, mode);
-            // The Chars iterator moved forward.
-            callback(0..(literal_text.len() - chars.as_str().len()), result);
+            let mut chars = src.chars();
+            let res = unescape_char_or_byte(&mut chars, mode == Mode::Byte);
+            callback(0..(src.len() - chars.as_str().len()), res);
         }
-        Mode::Str | Mode::ByteStr => unescape_str_or_byte_str(literal_text, mode, callback),
-        // NOTE: Raw strings do not perform any explicit character escaping, here we
-        // only translate CRLF to LF and produce errors on bare CR.
+        Mode::Str | Mode::ByteStr => unescape_str_or_byte_str(src, mode == Mode::ByteStr, callback),
         Mode::RawStr | Mode::RawByteStr => {
-            unescape_raw_str_or_raw_byte_str(literal_text, mode, callback)
+            unescape_raw_str_or_raw_byte_str(src, mode == Mode::RawByteStr, callback)
         }
     }
 }
 
-/// Takes a contents of a byte, byte string or raw byte string (without quotes)
-/// and produces a sequence of bytes or errors.
-/// Values are returned through invoking of the provided callback.
-pub fn unescape_byte_literal<F>(literal_text: &str, mode: Mode, callback: &mut F)
-where
-    F: FnMut(Range<usize>, Result<u8, EscapeError>),
-{
-    debug_assert!(mode.is_bytes());
-    unescape_literal(literal_text, mode, &mut |range, result| {
-        callback(range, result.map(byte_from_char));
-    })
-}
-
 /// Takes a contents of a char literal (without quotes), and returns an
-/// unescaped char or an error
-pub fn unescape_char(literal_text: &str) -> Result<char, (usize, EscapeError)> {
-    let mut chars = literal_text.chars();
-    unescape_char_or_byte(&mut chars, Mode::Char)
-        .map_err(|err| (literal_text.len() - chars.as_str().len(), err))
+/// unescaped char or an error.
+pub fn unescape_char(src: &str) -> Result<char, EscapeError> {
+    unescape_char_or_byte(&mut src.chars(), false)
 }
 
 /// Takes a contents of a byte literal (without quotes), and returns an
 /// unescaped byte or an error.
-pub fn unescape_byte(literal_text: &str) -> Result<u8, (usize, EscapeError)> {
-    let mut chars = literal_text.chars();
-    unescape_char_or_byte(&mut chars, Mode::Byte)
-        .map(byte_from_char)
-        .map_err(|err| (literal_text.len() - chars.as_str().len(), err))
+pub fn unescape_byte(src: &str) -> Result<u8, EscapeError> {
+    unescape_char_or_byte(&mut src.chars(), true).map(byte_from_char)
 }
 
 /// What kind of literal do we parse.
@@ -147,7 +124,7 @@ impl Mode {
         }
     }
 
-    pub fn is_bytes(self) -> bool {
+    pub fn is_byte(self) -> bool {
         match self {
             Mode::Byte | Mode::ByteStr | Mode::RawByteStr => true,
             Mode::Char | Mode::Str | Mode::RawStr => false,
@@ -155,12 +132,9 @@ impl Mode {
     }
 }
 
-fn scan_escape(chars: &mut Chars<'_>, mode: Mode) -> Result<char, EscapeError> {
+fn scan_escape(chars: &mut Chars<'_>, is_byte: bool) -> Result<char, EscapeError> {
     // Previous character was '\\', unescape what follows.
-
-    let second_char = chars.next().ok_or(EscapeError::LoneSlash)?;
-
-    let res = match second_char {
+    let res = match chars.next().ok_or(EscapeError::LoneSlash)? {
         '"' => '"',
         'n' => '\n',
         'r' => '\r',
@@ -181,7 +155,7 @@ fn scan_escape(chars: &mut Chars<'_>, mode: Mode) -> Result<char, EscapeError> {
             let value = hi * 16 + lo;
 
             // For a non-byte literal verify that it is within ASCII range.
-            if !mode.is_bytes() && !is_ascii(value) {
+            if !is_byte && !is_ascii(value) {
                 return Err(EscapeError::OutOfRangeHexEscape);
             }
             let value = value as u8;
@@ -217,7 +191,7 @@ fn scan_escape(chars: &mut Chars<'_>, mode: Mode) -> Result<char, EscapeError> {
 
                         // Incorrect syntax has higher priority for error reporting
                         // than unallowed value for a literal.
-                        if mode.is_bytes() {
+                        if is_byte {
                             return Err(EscapeError::UnicodeEscapeInByte);
                         }
 
@@ -249,23 +223,22 @@ fn scan_escape(chars: &mut Chars<'_>, mode: Mode) -> Result<char, EscapeError> {
 }
 
 #[inline]
-fn ascii_check(first_char: char, mode: Mode) -> Result<char, EscapeError> {
-    if mode.is_bytes() && !first_char.is_ascii() {
+fn ascii_check(c: char, is_byte: bool) -> Result<char, EscapeError> {
+    if is_byte && !c.is_ascii() {
         // Byte literal can't be a non-ascii character.
         Err(EscapeError::NonAsciiCharInByte)
     } else {
-        Ok(first_char)
+        Ok(c)
     }
 }
 
-fn unescape_char_or_byte(chars: &mut Chars<'_>, mode: Mode) -> Result<char, EscapeError> {
-    debug_assert!(mode == Mode::Char || mode == Mode::Byte);
-    let first_char = chars.next().ok_or(EscapeError::ZeroChars)?;
-    let res = match first_char {
-        '\\' => scan_escape(chars, mode),
+fn unescape_char_or_byte(chars: &mut Chars<'_>, is_byte: bool) -> Result<char, EscapeError> {
+    let c = chars.next().ok_or(EscapeError::ZeroChars)?;
+    let res = match c {
+        '\\' => scan_escape(chars, is_byte),
         '\n' | '\t' | '\'' => Err(EscapeError::EscapeOnlyChar),
         '\r' => Err(EscapeError::BareCarriageReturn),
-        _ => ascii_check(first_char, mode),
+        _ => ascii_check(c, is_byte),
     }?;
     if chars.next().is_some() {
         return Err(EscapeError::MoreThanOneChar);
@@ -275,20 +248,20 @@ fn unescape_char_or_byte(chars: &mut Chars<'_>, mode: Mode) -> Result<char, Esca
 
 /// Takes a contents of a string literal (without quotes) and produces a
 /// sequence of escaped characters or errors.
-fn unescape_str_or_byte_str<F>(src: &str, mode: Mode, callback: &mut F)
+fn unescape_str_or_byte_str<F>(src: &str, is_byte: bool, callback: &mut F)
 where
     F: FnMut(Range<usize>, Result<char, EscapeError>),
 {
-    debug_assert!(mode == Mode::Str || mode == Mode::ByteStr);
-    let initial_len = src.len();
     let mut chars = src.chars();
-    while let Some(first_char) = chars.next() {
-        let start = initial_len - chars.as_str().len() - first_char.len_utf8();
 
-        let unescaped_char = match first_char {
+    // The `start` and `end` computation here is complicated because
+    // `skip_ascii_whitespace` makes us to skip over chars without counting
+    // them in the range computation.
+    while let Some(c) = chars.next() {
+        let start = src.len() - chars.as_str().len() - c.len_utf8();
+        let res = match c {
             '\\' => {
-                let second_char = chars.clone().next();
-                match second_char {
+                match chars.clone().next() {
                     Some('\n') => {
                         // Rust language specification requires us to skip whitespaces
                         // if unescaped '\' character is followed by '\n'.
@@ -297,17 +270,17 @@ where
                         skip_ascii_whitespace(&mut chars, start, callback);
                         continue;
                     }
-                    _ => scan_escape(&mut chars, mode),
+                    _ => scan_escape(&mut chars, is_byte),
                 }
             }
             '\n' => Ok('\n'),
             '\t' => Ok('\t'),
             '"' => Err(EscapeError::EscapeOnlyChar),
             '\r' => Err(EscapeError::BareCarriageReturn),
-            _ => ascii_check(first_char, mode),
+            _ => ascii_check(c, is_byte),
         };
-        let end = initial_len - chars.as_str().len();
-        callback(start..end, unescaped_char);
+        let end = src.len() - chars.as_str().len();
+        callback(start..end, res);
     }
 
     fn skip_ascii_whitespace<F>(chars: &mut Chars<'_>, start: usize, callback: &mut F)
@@ -340,30 +313,29 @@ where
 /// Takes a contents of a string literal (without quotes) and produces a
 /// sequence of characters or errors.
 /// NOTE: Raw strings do not perform any explicit character escaping, here we
-/// only translate CRLF to LF and produce errors on bare CR.
-fn unescape_raw_str_or_raw_byte_str<F>(literal_text: &str, mode: Mode, callback: &mut F)
+/// only produce errors on bare CR.
+fn unescape_raw_str_or_raw_byte_str<F>(src: &str, is_byte: bool, callback: &mut F)
 where
     F: FnMut(Range<usize>, Result<char, EscapeError>),
 {
-    debug_assert!(mode == Mode::RawStr || mode == Mode::RawByteStr);
-    let initial_len = literal_text.len();
+    let mut chars = src.chars();
 
-    let mut chars = literal_text.chars();
-    while let Some(curr) = chars.next() {
-        let start = initial_len - chars.as_str().len() - curr.len_utf8();
-
-        let result = match curr {
+    // The `start` and `end` computation here matches the one in
+    // `unescape_str_or_byte_str` for consistency, even though this function
+    // doesn't have to worry about skipping any chars.
+    while let Some(c) = chars.next() {
+        let start = src.len() - chars.as_str().len() - c.len_utf8();
+        let res = match c {
             '\r' => Err(EscapeError::BareCarriageReturnInRawString),
-            c if mode.is_bytes() && !c.is_ascii() => Err(EscapeError::NonAsciiCharInByteString),
-            c => Ok(c),
+            _ => ascii_check(c, is_byte),
         };
-        let end = initial_len - chars.as_str().len();
-
-        callback(start..end, result);
+        let end = src.len() - chars.as_str().len();
+        callback(start..end, res);
     }
 }
 
-fn byte_from_char(c: char) -> u8 {
+#[inline]
+pub fn byte_from_char(c: char) -> u8 {
     let res = c as u32;
     debug_assert!(res <= u8::MAX as u32, "guaranteed because of Mode::ByteStr");
     res as u8
diff --git a/compiler/rustc_lexer/src/unescape/tests.rs b/compiler/rustc_lexer/src/unescape/tests.rs
index fa61554afde6..c7ca8fd16ae4 100644
--- a/compiler/rustc_lexer/src/unescape/tests.rs
+++ b/compiler/rustc_lexer/src/unescape/tests.rs
@@ -3,8 +3,7 @@ use super::*;
 #[test]
 fn test_unescape_char_bad() {
     fn check(literal_text: &str, expected_error: EscapeError) {
-        let actual_result = unescape_char(literal_text).map_err(|(_offset, err)| err);
-        assert_eq!(actual_result, Err(expected_error));
+        assert_eq!(unescape_char(literal_text), Err(expected_error));
     }
 
     check("", EscapeError::ZeroChars);
@@ -68,8 +67,7 @@ fn test_unescape_char_bad() {
 #[test]
 fn test_unescape_char_good() {
     fn check(literal_text: &str, expected_char: char) {
-        let actual_result = unescape_char(literal_text);
-        assert_eq!(actual_result, Ok(expected_char));
+        assert_eq!(unescape_char(literal_text), Ok(expected_char));
     }
 
     check("a", 'a');
@@ -149,8 +147,7 @@ fn test_unescape_str_good() {
 #[test]
 fn test_unescape_byte_bad() {
     fn check(literal_text: &str, expected_error: EscapeError) {
-        let actual_result = unescape_byte(literal_text).map_err(|(_offset, err)| err);
-        assert_eq!(actual_result, Err(expected_error));
+        assert_eq!(unescape_byte(literal_text), Err(expected_error));
     }
 
     check("", EscapeError::ZeroChars);
@@ -219,8 +216,7 @@ fn test_unescape_byte_bad() {
 #[test]
 fn test_unescape_byte_good() {
     fn check(literal_text: &str, expected_byte: u8) {
-        let actual_result = unescape_byte(literal_text);
-        assert_eq!(actual_result, Ok(expected_byte));
+        assert_eq!(unescape_byte(literal_text), Ok(expected_byte));
     }
 
     check("a", b'a');
@@ -246,10 +242,10 @@ fn test_unescape_byte_good() {
 fn test_unescape_byte_str_good() {
     fn check(literal_text: &str, expected: &[u8]) {
         let mut buf = Ok(Vec::with_capacity(literal_text.len()));
-        unescape_byte_literal(literal_text, Mode::ByteStr, &mut |range, c| {
+        unescape_literal(literal_text, Mode::ByteStr, &mut |range, c| {
             if let Ok(b) = &mut buf {
                 match c {
-                    Ok(c) => b.push(c),
+                    Ok(c) => b.push(byte_from_char(c)),
                     Err(e) => buf = Err((range, e)),
                 }
             }
@@ -280,18 +276,13 @@ fn test_unescape_raw_str() {
 
 #[test]
 fn test_unescape_raw_byte_str() {
-    fn check(literal: &str, expected: &[(Range<usize>, Result<u8, EscapeError>)]) {
+    fn check(literal: &str, expected: &[(Range<usize>, Result<char, EscapeError>)]) {
         let mut unescaped = Vec::with_capacity(literal.len());
-        unescape_byte_literal(literal, Mode::RawByteStr, &mut |range, res| {
-            unescaped.push((range, res))
-        });
+        unescape_literal(literal, Mode::RawByteStr, &mut |range, res| unescaped.push((range, res)));
         assert_eq!(unescaped, expected);
     }
 
     check("\r", &[(0..1, Err(EscapeError::BareCarriageReturnInRawString))]);
-    check("🦀", &[(0..4, Err(EscapeError::NonAsciiCharInByteString))]);
-    check(
-        "🦀a",
-        &[(0..4, Err(EscapeError::NonAsciiCharInByteString)), (4..5, Ok(byte_from_char('a')))],
-    );
+    check("🦀", &[(0..4, Err(EscapeError::NonAsciiCharInByte))]);
+    check("🦀a", &[(0..4, Err(EscapeError::NonAsciiCharInByte)), (4..5, Ok('a'))]);
 }
diff --git a/compiler/rustc_lint/src/builtin.rs b/compiler/rustc_lint/src/builtin.rs
index 53c491051342..27c04d828111 100644
--- a/compiler/rustc_lint/src/builtin.rs
+++ b/compiler/rustc_lint/src/builtin.rs
@@ -40,7 +40,7 @@ use rustc_feature::{deprecated_attributes, AttributeGate, BuiltinAttribute, Gate
 use rustc_hir as hir;
 use rustc_hir::def::{DefKind, Res};
 use rustc_hir::def_id::{DefId, LocalDefId, LocalDefIdSet, CRATE_DEF_ID};
-use rustc_hir::{ForeignItemKind, GenericParamKind, HirId, PatKind, PredicateOrigin};
+use rustc_hir::{ForeignItemKind, GenericParamKind, HirId, Node, PatKind, PredicateOrigin};
 use rustc_index::vec::Idx;
 use rustc_middle::lint::in_external_macro;
 use rustc_middle::ty::layout::{LayoutError, LayoutOf};
@@ -177,7 +177,7 @@ impl<'tcx> LateLintPass<'tcx> for BoxPointers {
             | hir::ItemKind::Enum(..)
             | hir::ItemKind::Struct(..)
             | hir::ItemKind::Union(..) => {
-                self.check_heap_type(cx, it.span, cx.tcx.type_of(it.def_id))
+                self.check_heap_type(cx, it.span, cx.tcx.type_of(it.owner_id))
             }
             _ => (),
         }
@@ -563,7 +563,7 @@ impl MissingDoc {
         // It's an option so the crate root can also use this function (it doesn't
         // have a `NodeId`).
         if def_id != CRATE_DEF_ID {
-            if !cx.access_levels.is_exported(def_id) {
+            if !cx.effective_visibilities.is_exported(def_id) {
                 return;
             }
         }
@@ -606,9 +606,9 @@ impl<'tcx> LateLintPass<'tcx> for MissingDoc {
         match it.kind {
             hir::ItemKind::Trait(..) => {
                 // Issue #11592: traits are always considered exported, even when private.
-                if cx.tcx.visibility(it.def_id)
+                if cx.tcx.visibility(it.owner_id)
                     == ty::Visibility::Restricted(
-                        cx.tcx.parent_module_from_def_id(it.def_id.def_id).to_def_id(),
+                        cx.tcx.parent_module_from_def_id(it.owner_id.def_id).to_def_id(),
                     )
                 {
                     return;
@@ -627,15 +627,15 @@ impl<'tcx> LateLintPass<'tcx> for MissingDoc {
             _ => return,
         };
 
-        let (article, desc) = cx.tcx.article_and_description(it.def_id.to_def_id());
+        let (article, desc) = cx.tcx.article_and_description(it.owner_id.to_def_id());
 
-        self.check_missing_docs_attrs(cx, it.def_id.def_id, article, desc);
+        self.check_missing_docs_attrs(cx, it.owner_id.def_id, article, desc);
     }
 
     fn check_trait_item(&mut self, cx: &LateContext<'_>, trait_item: &hir::TraitItem<'_>) {
-        let (article, desc) = cx.tcx.article_and_description(trait_item.def_id.to_def_id());
+        let (article, desc) = cx.tcx.article_and_description(trait_item.owner_id.to_def_id());
 
-        self.check_missing_docs_attrs(cx, trait_item.def_id.def_id, article, desc);
+        self.check_missing_docs_attrs(cx, trait_item.owner_id.def_id, article, desc);
     }
 
     fn check_impl_item(&mut self, cx: &LateContext<'_>, impl_item: &hir::ImplItem<'_>) {
@@ -662,13 +662,13 @@ impl<'tcx> LateLintPass<'tcx> for MissingDoc {
             }
         }
 
-        let (article, desc) = cx.tcx.article_and_description(impl_item.def_id.to_def_id());
-        self.check_missing_docs_attrs(cx, impl_item.def_id.def_id, article, desc);
+        let (article, desc) = cx.tcx.article_and_description(impl_item.owner_id.to_def_id());
+        self.check_missing_docs_attrs(cx, impl_item.owner_id.def_id, article, desc);
     }
 
     fn check_foreign_item(&mut self, cx: &LateContext<'_>, foreign_item: &hir::ForeignItem<'_>) {
-        let (article, desc) = cx.tcx.article_and_description(foreign_item.def_id.to_def_id());
-        self.check_missing_docs_attrs(cx, foreign_item.def_id.def_id, article, desc);
+        let (article, desc) = cx.tcx.article_and_description(foreign_item.owner_id.to_def_id());
+        self.check_missing_docs_attrs(cx, foreign_item.owner_id.def_id, article, desc);
     }
 
     fn check_field_def(&mut self, cx: &LateContext<'_>, sf: &hir::FieldDef<'_>) {
@@ -721,7 +721,7 @@ declare_lint_pass!(MissingCopyImplementations => [MISSING_COPY_IMPLEMENTATIONS])
 
 impl<'tcx> LateLintPass<'tcx> for MissingCopyImplementations {
     fn check_item(&mut self, cx: &LateContext<'_>, item: &hir::Item<'_>) {
-        if !cx.access_levels.is_reachable(item.def_id.def_id) {
+        if !cx.effective_visibilities.is_reachable(item.owner_id.def_id) {
             return;
         }
         let (def, ty) = match item.kind {
@@ -729,21 +729,21 @@ impl<'tcx> LateLintPass<'tcx> for MissingCopyImplementations {
                 if !ast_generics.params.is_empty() {
                     return;
                 }
-                let def = cx.tcx.adt_def(item.def_id);
+                let def = cx.tcx.adt_def(item.owner_id);
                 (def, cx.tcx.mk_adt(def, cx.tcx.intern_substs(&[])))
             }
             hir::ItemKind::Union(_, ref ast_generics) => {
                 if !ast_generics.params.is_empty() {
                     return;
                 }
-                let def = cx.tcx.adt_def(item.def_id);
+                let def = cx.tcx.adt_def(item.owner_id);
                 (def, cx.tcx.mk_adt(def, cx.tcx.intern_substs(&[])))
             }
             hir::ItemKind::Enum(_, ref ast_generics) => {
                 if !ast_generics.params.is_empty() {
                     return;
                 }
-                let def = cx.tcx.adt_def(item.def_id);
+                let def = cx.tcx.adt_def(item.owner_id);
                 (def, cx.tcx.mk_adt(def, cx.tcx.intern_substs(&[])))
             }
             _ => return,
@@ -752,7 +752,7 @@ impl<'tcx> LateLintPass<'tcx> for MissingCopyImplementations {
             return;
         }
         let param_env = ty::ParamEnv::empty();
-        if ty.is_copy_modulo_regions(cx.tcx.at(item.span), param_env) {
+        if ty.is_copy_modulo_regions(cx.tcx, param_env) {
             return;
         }
         if can_type_implement_copy(
@@ -814,7 +814,7 @@ impl_lint_pass!(MissingDebugImplementations => [MISSING_DEBUG_IMPLEMENTATIONS]);
 
 impl<'tcx> LateLintPass<'tcx> for MissingDebugImplementations {
     fn check_item(&mut self, cx: &LateContext<'_>, item: &hir::Item<'_>) {
-        if !cx.access_levels.is_reachable(item.def_id.def_id) {
+        if !cx.effective_visibilities.is_reachable(item.owner_id.def_id) {
             return;
         }
 
@@ -841,7 +841,7 @@ impl<'tcx> LateLintPass<'tcx> for MissingDebugImplementations {
             debug!("{:?}", self.impling_types);
         }
 
-        if !self.impling_types.as_ref().unwrap().contains(&item.def_id.def_id) {
+        if !self.impling_types.as_ref().unwrap().contains(&item.owner_id.def_id) {
             cx.struct_span_lint(
                 MISSING_DEBUG_IMPLEMENTATIONS,
                 item.span,
@@ -1226,7 +1226,7 @@ impl<'tcx> LateLintPass<'tcx> for InvalidNoMangleItems {
                             check_no_mangle_on_generic_fn(
                                 no_mangle_attr,
                                 Some(generics),
-                                cx.tcx.hir().get_generics(it.id.def_id.def_id).unwrap(),
+                                cx.tcx.hir().get_generics(it.id.owner_id.def_id).unwrap(),
                                 it.span,
                             );
                         }
@@ -1385,7 +1385,8 @@ impl UnreachablePub {
         exportable: bool,
     ) {
         let mut applicability = Applicability::MachineApplicable;
-        if cx.tcx.visibility(def_id).is_public() && !cx.access_levels.is_reachable(def_id) {
+        if cx.tcx.visibility(def_id).is_public() && !cx.effective_visibilities.is_reachable(def_id)
+        {
             if vis_span.from_expansion() {
                 applicability = Applicability::MaybeIncorrect;
             }
@@ -1414,22 +1415,26 @@ impl<'tcx> LateLintPass<'tcx> for UnreachablePub {
         if let hir::ItemKind::Use(_, hir::UseKind::ListStem) = &item.kind {
             return;
         }
-        self.perform_lint(cx, "item", item.def_id.def_id, item.vis_span, true);
+        self.perform_lint(cx, "item", item.owner_id.def_id, item.vis_span, true);
     }
 
     fn check_foreign_item(&mut self, cx: &LateContext<'_>, foreign_item: &hir::ForeignItem<'tcx>) {
-        self.perform_lint(cx, "item", foreign_item.def_id.def_id, foreign_item.vis_span, true);
+        self.perform_lint(cx, "item", foreign_item.owner_id.def_id, foreign_item.vis_span, true);
     }
 
     fn check_field_def(&mut self, cx: &LateContext<'_>, field: &hir::FieldDef<'_>) {
-        let def_id = cx.tcx.hir().local_def_id(field.hir_id);
+        let map = cx.tcx.hir();
+        let def_id = map.local_def_id(field.hir_id);
+        if matches!(map.get(map.get_parent_node(field.hir_id)), Node::Variant(_)) {
+            return;
+        }
         self.perform_lint(cx, "field", def_id, field.vis_span, false);
     }
 
     fn check_impl_item(&mut self, cx: &LateContext<'_>, impl_item: &hir::ImplItem<'_>) {
         // Only lint inherent impl items.
-        if cx.tcx.associated_item(impl_item.def_id).trait_item_def_id.is_none() {
-            self.perform_lint(cx, "item", impl_item.def_id.def_id, impl_item.vis_span, false);
+        if cx.tcx.associated_item(impl_item.owner_id).trait_item_def_id.is_none() {
+            self.perform_lint(cx, "item", impl_item.owner_id.def_id, impl_item.vis_span, false);
         }
     }
 }
@@ -1638,7 +1643,7 @@ impl<'tcx> LateLintPass<'tcx> for TrivialConstraints {
         use rustc_middle::ty::PredicateKind::*;
 
         if cx.tcx.features().trivial_bounds {
-            let predicates = cx.tcx.predicates_of(item.def_id);
+            let predicates = cx.tcx.predicates_of(item.owner_id);
             for &(predicate, span) in predicates.predicates {
                 let predicate_kind_name = match predicate.kind().skip_binder() {
                     Trait(..) => "trait",
@@ -1881,7 +1886,7 @@ impl<'tcx> LateLintPass<'tcx> for UnnameableTestItems {
             if let hir::ItemKind::Mod(..) = it.kind {
             } else {
                 self.items_nameable = false;
-                self.boundary = Some(it.def_id);
+                self.boundary = Some(it.owner_id);
             }
             return;
         }
@@ -1898,7 +1903,7 @@ impl<'tcx> LateLintPass<'tcx> for UnnameableTestItems {
     }
 
     fn check_item_post(&mut self, _cx: &LateContext<'_>, it: &hir::Item<'_>) {
-        if !self.items_nameable && self.boundary == Some(it.def_id) {
+        if !self.items_nameable && self.boundary == Some(it.owner_id) {
             self.items_nameable = true;
         }
     }
@@ -2164,7 +2169,7 @@ impl<'tcx> LateLintPass<'tcx> for ExplicitOutlivesRequirements {
     fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx hir::Item<'_>) {
         use rustc_middle::middle::resolve_lifetime::Region;
 
-        let def_id = item.def_id.def_id;
+        let def_id = item.owner_id.def_id;
         if let hir::ItemKind::Struct(_, ref hir_generics)
         | hir::ItemKind::Enum(_, ref hir_generics)
         | hir::ItemKind::Union(_, ref hir_generics) = item.kind
@@ -2743,7 +2748,7 @@ impl ClashingExternDeclarations {
     /// Insert a new foreign item into the seen set. If a symbol with the same name already exists
     /// for the item, return its HirId without updating the set.
     fn insert(&mut self, tcx: TyCtxt<'_>, fi: &hir::ForeignItem<'_>) -> Option<HirId> {
-        let did = fi.def_id.to_def_id();
+        let did = fi.owner_id.to_def_id();
         let instance = Instance::new(did, ty::List::identity_for_item(tcx, did));
         let name = Symbol::intern(tcx.symbol_name(instance).name);
         if let Some(&hir_id) = self.seen_decls.get(&name) {
@@ -2761,14 +2766,14 @@ impl ClashingExternDeclarations {
     /// symbol's name.
     fn name_of_extern_decl(tcx: TyCtxt<'_>, fi: &hir::ForeignItem<'_>) -> SymbolName {
         if let Some((overridden_link_name, overridden_link_name_span)) =
-            tcx.codegen_fn_attrs(fi.def_id).link_name.map(|overridden_link_name| {
+            tcx.codegen_fn_attrs(fi.owner_id).link_name.map(|overridden_link_name| {
                 // FIXME: Instead of searching through the attributes again to get span
                 // information, we could have codegen_fn_attrs also give span information back for
                 // where the attribute was defined. However, until this is found to be a
                 // bottleneck, this does just fine.
                 (
                     overridden_link_name,
-                    tcx.get_attr(fi.def_id.to_def_id(), sym::link_name).unwrap().span,
+                    tcx.get_attr(fi.owner_id.to_def_id(), sym::link_name).unwrap().span,
                 )
             })
         {
@@ -2985,10 +2990,10 @@ impl<'tcx> LateLintPass<'tcx> for ClashingExternDeclarations {
             let tcx = cx.tcx;
             if let Some(existing_hid) = self.insert(tcx, this_fi) {
                 let existing_decl_ty = tcx.type_of(tcx.hir().local_def_id(existing_hid));
-                let this_decl_ty = tcx.type_of(this_fi.def_id);
+                let this_decl_ty = tcx.type_of(this_fi.owner_id);
                 debug!(
                     "ClashingExternDeclarations: Comparing existing {:?}: {:?} to this {:?}: {:?}",
-                    existing_hid, existing_decl_ty, this_fi.def_id, this_decl_ty
+                    existing_hid, existing_decl_ty, this_fi.owner_id, this_decl_ty
                 );
                 // Check that the declarations match.
                 if !Self::structurally_same_type(
diff --git a/compiler/rustc_lint/src/context.rs b/compiler/rustc_lint/src/context.rs
index 63a11877333e..28f6ac61c5bd 100644
--- a/compiler/rustc_lint/src/context.rs
+++ b/compiler/rustc_lint/src/context.rs
@@ -31,7 +31,7 @@ use rustc_hir as hir;
 use rustc_hir::def::Res;
 use rustc_hir::def_id::{CrateNum, DefId};
 use rustc_hir::definitions::{DefPathData, DisambiguatedDefPathData};
-use rustc_middle::middle::privacy::AccessLevels;
+use rustc_middle::middle::privacy::EffectiveVisibilities;
 use rustc_middle::middle::stability;
 use rustc_middle::ty::layout::{LayoutError, LayoutOfHelpers, TyAndLayout};
 use rustc_middle::ty::print::with_no_trimmed_paths;
@@ -542,7 +542,7 @@ pub struct LateContext<'tcx> {
     pub param_env: ty::ParamEnv<'tcx>,
 
     /// Items accessible from the crate being checked.
-    pub access_levels: &'tcx AccessLevels,
+    pub effective_visibilities: &'tcx EffectiveVisibilities,
 
     /// The store of registered lints and the lint levels.
     pub lint_store: &'tcx LintStore,
@@ -579,6 +579,7 @@ pub trait LintContext: Sized {
     /// Return value of the `decorate` closure is ignored, see [`struct_lint_level`] for a detailed explanation.
     ///
     /// [`struct_lint_level`]: rustc_middle::lint::struct_lint_level#decorate-signature
+    #[rustc_lint_diagnostics]
     fn lookup_with_diagnostics(
         &self,
         lint: &'static Lint,
@@ -882,6 +883,7 @@ pub trait LintContext: Sized {
     /// Return value of the `decorate` closure is ignored, see [`struct_lint_level`] for a detailed explanation.
     ///
     /// [`struct_lint_level`]: rustc_middle::lint::struct_lint_level#decorate-signature
+    #[rustc_lint_diagnostics]
     fn lookup<S: Into<MultiSpan>>(
         &self,
         lint: &'static Lint,
@@ -908,6 +910,7 @@ pub trait LintContext: Sized {
     /// Return value of the `decorate` closure is ignored, see [`struct_lint_level`] for a detailed explanation.
     ///
     /// [`struct_lint_level`]: rustc_middle::lint::struct_lint_level#decorate-signature
+    #[rustc_lint_diagnostics]
     fn struct_span_lint<S: Into<MultiSpan>>(
         &self,
         lint: &'static Lint,
@@ -933,6 +936,7 @@ pub trait LintContext: Sized {
     /// Return value of the `decorate` closure is ignored, see [`struct_lint_level`] for a detailed explanation.
     ///
     /// [`struct_lint_level`]: rustc_middle::lint::struct_lint_level#decorate-signature
+    #[rustc_lint_diagnostics]
     fn lint(
         &self,
         lint: &'static Lint,
diff --git a/compiler/rustc_lint/src/errors.rs b/compiler/rustc_lint/src/errors.rs
index a49d1bdacc25..1a769893f552 100644
--- a/compiler/rustc_lint/src/errors.rs
+++ b/compiler/rustc_lint/src/errors.rs
@@ -83,7 +83,7 @@ pub struct UnknownToolInScopedLint {
 pub struct BuiltinEllpisisInclusiveRangePatterns {
     #[primary_span]
     pub span: Span,
-    #[suggestion_short(code = "{replace}", applicability = "machine-applicable")]
+    #[suggestion(style = "short", code = "{replace}", applicability = "machine-applicable")]
     pub suggestion: Span,
     pub replace: String,
 }
diff --git a/compiler/rustc_lint/src/for_loops_over_fallibles.rs b/compiler/rustc_lint/src/for_loops_over_fallibles.rs
index ed8d424e0c62..4187850153cc 100644
--- a/compiler/rustc_lint/src/for_loops_over_fallibles.rs
+++ b/compiler/rustc_lint/src/for_loops_over_fallibles.rs
@@ -3,11 +3,9 @@ use crate::{LateContext, LateLintPass, LintContext};
 use hir::{Expr, Pat};
 use rustc_errors::{Applicability, DelayDm};
 use rustc_hir as hir;
-use rustc_infer::traits::TraitEngine;
 use rustc_infer::{infer::TyCtxtInferExt, traits::ObligationCause};
 use rustc_middle::ty::{self, List};
 use rustc_span::{sym, Span};
-use rustc_trait_selection::traits::TraitEngineExt;
 
 declare_lint! {
     /// The `for_loops_over_fallibles` lint checks for `for` loops over `Option` or `Result` values.
@@ -160,24 +158,19 @@ fn suggest_question_mark<'tcx>(
 
     let ty = substs.type_at(0);
     let infcx = cx.tcx.infer_ctxt().build();
-    let mut fulfill_cx = <dyn TraitEngine<'_>>::new(infcx.tcx);
-
     let cause = ObligationCause::new(
         span,
         body_id.hir_id,
         rustc_infer::traits::ObligationCauseCode::MiscObligation,
     );
-    fulfill_cx.register_bound(
+    let errors = rustc_trait_selection::traits::fully_solve_bound(
         &infcx,
+        cause,
         ty::ParamEnv::empty(),
         // Erase any region vids from the type, which may not be resolved
         infcx.tcx.erase_regions(ty),
         into_iterator_did,
-        cause,
     );
 
-    // Select all, including ambiguous predicates
-    let errors = fulfill_cx.select_all_or_error(&infcx);
-
     errors.is_empty()
 }
diff --git a/compiler/rustc_lint/src/late.rs b/compiler/rustc_lint/src/late.rs
index d4e19ef6b223..303fcb1a1d15 100644
--- a/compiler/rustc_lint/src/late.rs
+++ b/compiler/rustc_lint/src/late.rs
@@ -338,14 +338,14 @@ fn late_lint_mod_pass<'tcx, T: LateLintPass<'tcx>>(
     module_def_id: LocalDefId,
     pass: T,
 ) {
-    let access_levels = &tcx.privacy_access_levels(());
+    let effective_visibilities = &tcx.effective_visibilities(());
 
     let context = LateContext {
         tcx,
         enclosing_body: None,
         cached_typeck_results: Cell::new(None),
         param_env: ty::ParamEnv::empty(),
-        access_levels,
+        effective_visibilities,
         lint_store: unerased_lint_store(tcx),
         last_node_with_lint_attrs: tcx.hir().local_def_id_to_hir_id(module_def_id),
         generics: None,
@@ -386,14 +386,14 @@ pub fn late_lint_mod<'tcx, T: LateLintPass<'tcx>>(
 }
 
 fn late_lint_pass_crate<'tcx, T: LateLintPass<'tcx>>(tcx: TyCtxt<'tcx>, pass: T) {
-    let access_levels = &tcx.privacy_access_levels(());
+    let effective_visibilities = &tcx.effective_visibilities(());
 
     let context = LateContext {
         tcx,
         enclosing_body: None,
         cached_typeck_results: Cell::new(None),
         param_env: ty::ParamEnv::empty(),
-        access_levels,
+        effective_visibilities,
         lint_store: unerased_lint_store(tcx),
         last_node_with_lint_attrs: hir::CRATE_HIR_ID,
         generics: None,
diff --git a/compiler/rustc_lint/src/let_underscore.rs b/compiler/rustc_lint/src/let_underscore.rs
index e1177c10414d..04d844d21dc3 100644
--- a/compiler/rustc_lint/src/let_underscore.rs
+++ b/compiler/rustc_lint/src/let_underscore.rs
@@ -11,6 +11,7 @@ declare_lint! {
     /// scope.
     ///
     /// ### Example
+    ///
     /// ```rust
     /// struct SomeStruct;
     /// impl Drop for SomeStruct {
diff --git a/compiler/rustc_lint/src/levels.rs b/compiler/rustc_lint/src/levels.rs
index db0a3419e6a5..efae26690063 100644
--- a/compiler/rustc_lint/src/levels.rs
+++ b/compiler/rustc_lint/src/levels.rs
@@ -163,7 +163,7 @@ fn shallow_lint_levels_on(tcx: TyCtxt<'_>, owner: hir::OwnerId) -> ShallowLintLe
         // Otherwise, we need to visit the attributes in source code order, so we fetch HIR and do
         // a standard visit.
         // FIXME(#102522) Just iterate on attrs once that iteration order matches HIR's.
-        _ => match tcx.hir().expect_owner(owner) {
+        _ => match tcx.hir().owner(owner) {
             hir::OwnerNode::Item(item) => levels.visit_item(item),
             hir::OwnerNode::ForeignItem(item) => levels.visit_foreign_item(item),
             hir::OwnerNode::TraitItem(item) => levels.visit_trait_item(item),
@@ -1073,6 +1073,7 @@ impl<'s, P: LintLevelsProvider> LintLevelsBuilder<'s, P> {
     /// Return value of the `decorate` closure is ignored, see [`struct_lint_level`] for a detailed explanation.
     ///
     /// [`struct_lint_level`]: rustc_middle::lint::struct_lint_level#decorate-signature
+    #[rustc_lint_diagnostics]
     pub(crate) fn struct_lint(
         &self,
         lint: &'static Lint,
diff --git a/compiler/rustc_lint/src/lib.rs b/compiler/rustc_lint/src/lib.rs
index fee6e080c4fc..ebb7de70e057 100644
--- a/compiler/rustc_lint/src/lib.rs
+++ b/compiler/rustc_lint/src/lib.rs
@@ -36,6 +36,7 @@
 #![feature(let_chains)]
 #![feature(min_specialization)]
 #![feature(never_type)]
+#![feature(rustc_attrs)]
 #![recursion_limit = "256"]
 
 #[macro_use]
@@ -212,7 +213,7 @@ macro_rules! late_lint_mod_passes {
                 TypeLimits: TypeLimits::new(),
                 NonSnakeCase: NonSnakeCase,
                 InvalidNoMangleItems: InvalidNoMangleItems,
-                // Depends on access levels
+                // Depends on effective visibilities
                 UnreachablePub: UnreachablePub,
                 ExplicitOutlivesRequirements: ExplicitOutlivesRequirements,
                 InvalidValue: InvalidValue,
diff --git a/compiler/rustc_lint/src/opaque_hidden_inferred_bound.rs b/compiler/rustc_lint/src/opaque_hidden_inferred_bound.rs
index ccc53707f7cf..619582c0539b 100644
--- a/compiler/rustc_lint/src/opaque_hidden_inferred_bound.rs
+++ b/compiler/rustc_lint/src/opaque_hidden_inferred_bound.rs
@@ -65,7 +65,7 @@ declare_lint_pass!(OpaqueHiddenInferredBound => [OPAQUE_HIDDEN_INFERRED_BOUND]);
 impl<'tcx> LateLintPass<'tcx> for OpaqueHiddenInferredBound {
     fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx hir::Item<'tcx>) {
         let hir::ItemKind::OpaqueTy(_) = &item.kind else { return; };
-        let def_id = item.def_id.def_id.to_def_id();
+        let def_id = item.owner_id.def_id.to_def_id();
         let infcx = &cx.tcx.infer_ctxt().build();
         // For every projection predicate in the opaque type's explicit bounds,
         // check that the type that we're assigning actually satisfies the bounds
@@ -154,8 +154,9 @@ struct OpaqueHiddenInferredBoundLint<'tcx> {
 }
 
 #[derive(Subdiagnostic)]
-#[suggestion_verbose(
+#[suggestion(
     lint_opaque_hidden_inferred_bound_sugg,
+    style = "verbose",
     applicability = "machine-applicable",
     code = " + {trait_ref}"
 )]
diff --git a/compiler/rustc_lint/src/traits.rs b/compiler/rustc_lint/src/traits.rs
index a118dda8b40f..f22f38aa2cea 100644
--- a/compiler/rustc_lint/src/traits.rs
+++ b/compiler/rustc_lint/src/traits.rs
@@ -89,7 +89,7 @@ impl<'tcx> LateLintPass<'tcx> for DropTraitConstraints {
     fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx hir::Item<'tcx>) {
         use rustc_middle::ty::PredicateKind::*;
 
-        let predicates = cx.tcx.explicit_predicates_of(item.def_id);
+        let predicates = cx.tcx.explicit_predicates_of(item.owner_id);
         for &(predicate, span) in predicates.predicates {
             let Trait(trait_predicate) = predicate.kind().skip_binder() else {
                 continue
diff --git a/compiler/rustc_lint/src/types.rs b/compiler/rustc_lint/src/types.rs
index 7c99bb2790fd..afc568f3a505 100644
--- a/compiler/rustc_lint/src/types.rs
+++ b/compiler/rustc_lint/src/types.rs
@@ -11,7 +11,7 @@ use rustc_middle::ty::subst::SubstsRef;
 use rustc_middle::ty::{self, AdtKind, DefIdTree, Ty, TyCtxt, TypeSuperVisitable, TypeVisitable};
 use rustc_span::source_map;
 use rustc_span::symbol::sym;
-use rustc_span::{Span, Symbol, DUMMY_SP};
+use rustc_span::{Span, Symbol};
 use rustc_target::abi::{Abi, WrappingRange};
 use rustc_target::abi::{Integer, TagEncoding, Variants};
 use rustc_target::spec::abi::Abi as SpecAbi;
@@ -360,7 +360,7 @@ fn lint_int_literal<'tcx>(
         }
 
         if lint_overflowing_range_endpoint(cx, lit, v, max, e, t.name_str()) {
-            // The overflowing literal lint was emited by `lint_overflowing_range_endpoint`.
+            // The overflowing literal lint was emitted by `lint_overflowing_range_endpoint`.
             return;
         }
 
@@ -429,7 +429,7 @@ fn lint_uint_literal<'tcx>(
             }
         }
         if lint_overflowing_range_endpoint(cx, lit, lit_val, max, e, t.name_str()) {
-            // The overflowing literal lint was emited by `lint_overflowing_range_endpoint`.
+            // The overflowing literal lint was emitted by `lint_overflowing_range_endpoint`.
             return;
         }
         if let Some(repr_str) = get_bin_hex_repr(cx, lit) {
@@ -931,7 +931,7 @@ impl<'a, 'tcx> ImproperCTypesVisitor<'a, 'tcx> {
         match *ty.kind() {
             ty::Adt(def, substs) => {
                 if def.is_box() && matches!(self.mode, CItemKind::Definition) {
-                    if ty.boxed_ty().is_sized(tcx.at(DUMMY_SP), self.cx.param_env) {
+                    if ty.boxed_ty().is_sized(tcx, self.cx.param_env) {
                         return FfiSafe;
                     } else {
                         return FfiUnsafe {
@@ -1082,7 +1082,7 @@ impl<'a, 'tcx> ImproperCTypesVisitor<'a, 'tcx> {
             ty::RawPtr(ty::TypeAndMut { ty, .. }) | ty::Ref(_, ty, _)
                 if {
                     matches!(self.mode, CItemKind::Definition)
-                        && ty.is_sized(self.cx.tcx.at(DUMMY_SP), self.cx.param_env)
+                        && ty.is_sized(self.cx.tcx, self.cx.param_env)
                 } =>
             {
                 FfiSafe
@@ -1195,35 +1195,30 @@ impl<'a, 'tcx> ImproperCTypesVisitor<'a, 'tcx> {
     }
 
     fn check_for_opaque_ty(&mut self, sp: Span, ty: Ty<'tcx>) -> bool {
-        struct ProhibitOpaqueTypes<'a, 'tcx> {
-            cx: &'a LateContext<'tcx>,
-        }
-
-        impl<'a, 'tcx> ty::visit::TypeVisitor<'tcx> for ProhibitOpaqueTypes<'a, 'tcx> {
+        struct ProhibitOpaqueTypes;
+        impl<'tcx> ty::visit::TypeVisitor<'tcx> for ProhibitOpaqueTypes {
             type BreakTy = Ty<'tcx>;
 
             fn visit_ty(&mut self, ty: Ty<'tcx>) -> ControlFlow<Self::BreakTy> {
-                match ty.kind() {
-                    ty::Opaque(..) => ControlFlow::Break(ty),
-                    // Consider opaque types within projections FFI-safe if they do not normalize
-                    // to more opaque types.
-                    ty::Projection(..) => {
-                        let ty = self.cx.tcx.normalize_erasing_regions(self.cx.param_env, ty);
+                if !ty.has_opaque_types() {
+                    return ControlFlow::CONTINUE;
+                }
 
-                        // If `ty` is an opaque type directly then `super_visit_with` won't invoke
-                        // this function again.
-                        if ty.has_opaque_types() {
-                            self.visit_ty(ty)
-                        } else {
-                            ControlFlow::CONTINUE
-                        }
-                    }
-                    _ => ty.super_visit_with(self),
+                if let ty::Opaque(..) = ty.kind() {
+                    ControlFlow::Break(ty)
+                } else {
+                    ty.super_visit_with(self)
                 }
             }
         }
 
-        if let Some(ty) = ty.visit_with(&mut ProhibitOpaqueTypes { cx: self.cx }).break_value() {
+        if let Some(ty) = self
+            .cx
+            .tcx
+            .normalize_erasing_regions(self.cx.param_env, ty)
+            .visit_with(&mut ProhibitOpaqueTypes)
+            .break_value()
+        {
             self.emit_ffi_unsafe_type_lint(ty, sp, fluent::lint_improper_ctypes_opaque, None);
             true
         } else {
@@ -1360,7 +1355,7 @@ declare_lint_pass!(VariantSizeDifferences => [VARIANT_SIZE_DIFFERENCES]);
 impl<'tcx> LateLintPass<'tcx> for VariantSizeDifferences {
     fn check_item(&mut self, cx: &LateContext<'_>, it: &hir::Item<'_>) {
         if let hir::ItemKind::Enum(ref enum_definition, _) = it.kind {
-            let t = cx.tcx.type_of(it.def_id);
+            let t = cx.tcx.type_of(it.owner_id);
             let ty = cx.tcx.erase_regions(t);
             let Ok(layout) = cx.layout_of(ty) else { return };
             let Variants::Multiple {
diff --git a/compiler/rustc_lint/src/unused.rs b/compiler/rustc_lint/src/unused.rs
index 46706e498445..ff0fb9bae923 100644
--- a/compiler/rustc_lint/src/unused.rs
+++ b/compiler/rustc_lint/src/unused.rs
@@ -9,7 +9,7 @@ use rustc_hir::def::{DefKind, Res};
 use rustc_hir::def_id::DefId;
 use rustc_infer::traits::util::elaborate_predicates_with_span;
 use rustc_middle::ty::adjustment;
-use rustc_middle::ty::{self, Ty};
+use rustc_middle::ty::{self, DefIdTree, Ty};
 use rustc_span::symbol::Symbol;
 use rustc_span::symbol::{kw, sym};
 use rustc_span::{BytePos, Span};
@@ -87,17 +87,33 @@ declare_lint_pass!(UnusedResults => [UNUSED_MUST_USE, UNUSED_RESULTS]);
 
 impl<'tcx> LateLintPass<'tcx> for UnusedResults {
     fn check_stmt(&mut self, cx: &LateContext<'_>, s: &hir::Stmt<'_>) {
-        let expr = match s.kind {
-            hir::StmtKind::Semi(ref expr) => &**expr,
-            _ => return,
-        };
+        let hir::StmtKind::Semi(expr) = s.kind else { return; };
 
         if let hir::ExprKind::Ret(..) = expr.kind {
             return;
         }
 
+        if let hir::ExprKind::Match(await_expr, _arms, hir::MatchSource::AwaitDesugar) = expr.kind
+            && let ty = cx.typeck_results().expr_ty(&await_expr)
+            && let ty::Opaque(future_def_id, _) = ty.kind()
+            && cx.tcx.ty_is_opaque_future(ty)
+            // FIXME: This also includes non-async fns that return `impl Future`.
+            && let async_fn_def_id = cx.tcx.parent(*future_def_id)
+            && check_must_use_def(
+                cx,
+                async_fn_def_id,
+                expr.span,
+                "output of future returned by ",
+                "",
+            )
+        {
+            // We have a bare `foo().await;` on an opaque type from an async function that was
+            // annotated with `#[must_use]`.
+            return;
+        }
+
         let ty = cx.typeck_results().expr_ty(&expr);
-        let type_permits_lack_of_use = check_must_use_ty(cx, ty, &expr, s.span, "", "", 1);
+        let type_permits_lack_of_use = check_must_use_ty(cx, ty, &expr, expr.span, "", "", 1);
 
         let mut fn_warned = false;
         let mut op_warned = false;
@@ -119,7 +135,7 @@ impl<'tcx> LateLintPass<'tcx> for UnusedResults {
             _ => None,
         };
         if let Some(def_id) = maybe_def_id {
-            fn_warned = check_must_use_def(cx, def_id, s.span, "return value of ", "");
+            fn_warned = check_must_use_def(cx, def_id, expr.span, "return value of ", "");
         } else if type_permits_lack_of_use {
             // We don't warn about unused unit or uninhabited types.
             // (See https://github.com/rust-lang/rust/issues/43806 for details.)
@@ -565,10 +581,24 @@ trait UnusedDelimLint {
             lint.set_arg("delim", Self::DELIM_STR);
             lint.set_arg("item", msg);
             if let Some((lo, hi)) = spans {
-                let replacement = vec![
-                    (lo, if keep_space.0 { " ".into() } else { "".into() }),
-                    (hi, if keep_space.1 { " ".into() } else { "".into() }),
-                ];
+                let sm = cx.sess().source_map();
+                let lo_replace =
+                    if keep_space.0 &&
+                        let Ok(snip) = sm.span_to_prev_source(lo) && !snip.ends_with(" ") {
+                        " ".to_string()
+                        } else {
+                            "".to_string()
+                        };
+
+                let hi_replace =
+                    if keep_space.1 &&
+                        let Ok(snip) = sm.span_to_next_source(hi) && !snip.starts_with(" ") {
+                        " ".to_string()
+                        } else {
+                            "".to_string()
+                        };
+
+                let replacement = vec![(lo, lo_replace), (hi, hi_replace)];
                 lint.multipart_suggestion(
                     fluent::suggestion,
                     replacement,
@@ -765,6 +795,7 @@ impl UnusedParens {
         value: &ast::Pat,
         avoid_or: bool,
         avoid_mut: bool,
+        keep_space: (bool, bool),
     ) {
         use ast::{BindingAnnotation, PatKind};
 
@@ -789,7 +820,7 @@ impl UnusedParens {
             } else {
                 None
             };
-            self.emit_unused_delims(cx, value.span, spans, "pattern", (false, false));
+            self.emit_unused_delims(cx, value.span, spans, "pattern", keep_space);
         }
     }
 }
@@ -798,7 +829,7 @@ impl EarlyLintPass for UnusedParens {
     fn check_expr(&mut self, cx: &EarlyContext<'_>, e: &ast::Expr) {
         match e.kind {
             ExprKind::Let(ref pat, _, _) | ExprKind::ForLoop(ref pat, ..) => {
-                self.check_unused_parens_pat(cx, pat, false, false);
+                self.check_unused_parens_pat(cx, pat, false, false, (true, true));
             }
             // We ignore parens in cases like `if (((let Some(0) = Some(1))))` because we already
             // handle a hard error for them during AST lowering in `lower_expr_mut`, but we still
@@ -842,6 +873,7 @@ impl EarlyLintPass for UnusedParens {
 
     fn check_pat(&mut self, cx: &EarlyContext<'_>, p: &ast::Pat) {
         use ast::{Mutability, PatKind::*};
+        let keep_space = (false, false);
         match &p.kind {
             // Do not lint on `(..)` as that will result in the other arms being useless.
             Paren(_)
@@ -849,33 +881,33 @@ impl EarlyLintPass for UnusedParens {
             | Wild | Rest | Lit(..) | MacCall(..) | Range(..) | Ident(.., None) | Path(..) => {},
             // These are list-like patterns; parens can always be removed.
             TupleStruct(_, _, ps) | Tuple(ps) | Slice(ps) | Or(ps) => for p in ps {
-                self.check_unused_parens_pat(cx, p, false, false);
+                self.check_unused_parens_pat(cx, p, false, false, keep_space);
             },
             Struct(_, _, fps, _) => for f in fps {
-                self.check_unused_parens_pat(cx, &f.pat, false, false);
+                self.check_unused_parens_pat(cx, &f.pat, false, false, keep_space);
             },
             // Avoid linting on `i @ (p0 | .. | pn)` and `box (p0 | .. | pn)`, #64106.
-            Ident(.., Some(p)) | Box(p) => self.check_unused_parens_pat(cx, p, true, false),
+            Ident(.., Some(p)) | Box(p) => self.check_unused_parens_pat(cx, p, true, false, keep_space),
             // Avoid linting on `&(mut x)` as `&mut x` has a different meaning, #55342.
             // Also avoid linting on `& mut? (p0 | .. | pn)`, #64106.
-            Ref(p, m) => self.check_unused_parens_pat(cx, p, true, *m == Mutability::Not),
+            Ref(p, m) => self.check_unused_parens_pat(cx, p, true, *m == Mutability::Not, keep_space),
         }
     }
 
     fn check_stmt(&mut self, cx: &EarlyContext<'_>, s: &ast::Stmt) {
         if let StmtKind::Local(ref local) = s.kind {
-            self.check_unused_parens_pat(cx, &local.pat, true, false);
+            self.check_unused_parens_pat(cx, &local.pat, true, false, (false, false));
         }
 
         <Self as UnusedDelimLint>::check_stmt(self, cx, s)
     }
 
     fn check_param(&mut self, cx: &EarlyContext<'_>, param: &ast::Param) {
-        self.check_unused_parens_pat(cx, &param.pat, true, false);
+        self.check_unused_parens_pat(cx, &param.pat, true, false, (false, false));
     }
 
     fn check_arm(&mut self, cx: &EarlyContext<'_>, arm: &ast::Arm) {
-        self.check_unused_parens_pat(cx, &arm.pat, false, false);
+        self.check_unused_parens_pat(cx, &arm.pat, false, false, (false, false));
     }
 
     fn check_ty(&mut self, cx: &EarlyContext<'_>, ty: &ast::Ty) {
diff --git a/compiler/rustc_lint_defs/src/builtin.rs b/compiler/rustc_lint_defs/src/builtin.rs
index 1fc2c4548649..b80facb1759e 100644
--- a/compiler/rustc_lint_defs/src/builtin.rs
+++ b/compiler/rustc_lint_defs/src/builtin.rs
@@ -1982,73 +1982,6 @@ declare_lint! {
     };
 }
 
-declare_lint! {
-    /// The `proc_macro_derive_resolution_fallback` lint detects proc macro
-    /// derives using inaccessible names from parent modules.
-    ///
-    /// ### Example
-    ///
-    /// ```rust,ignore (proc-macro)
-    /// // foo.rs
-    /// #![crate_type = "proc-macro"]
-    ///
-    /// extern crate proc_macro;
-    ///
-    /// use proc_macro::*;
-    ///
-    /// #[proc_macro_derive(Foo)]
-    /// pub fn foo1(a: TokenStream) -> TokenStream {
-    ///     drop(a);
-    ///     "mod __bar { static mut BAR: Option<Something> = None; }".parse().unwrap()
-    /// }
-    /// ```
-    ///
-    /// ```rust,ignore (needs-dependency)
-    /// // bar.rs
-    /// #[macro_use]
-    /// extern crate foo;
-    ///
-    /// struct Something;
-    ///
-    /// #[derive(Foo)]
-    /// struct Another;
-    ///
-    /// fn main() {}
-    /// ```
-    ///
-    /// This will produce:
-    ///
-    /// ```text
-    /// warning: cannot find type `Something` in this scope
-    ///  --> src/main.rs:8:10
-    ///   |
-    /// 8 | #[derive(Foo)]
-    ///   |          ^^^ names from parent modules are not accessible without an explicit import
-    ///   |
-    ///   = note: `#[warn(proc_macro_derive_resolution_fallback)]` on by default
-    ///   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-    ///   = note: for more information, see issue #50504 <https://github.com/rust-lang/rust/issues/50504>
-    /// ```
-    ///
-    /// ### Explanation
-    ///
-    /// If a proc-macro generates a module, the compiler unintentionally
-    /// allowed items in that module to refer to items in the crate root
-    /// without importing them. This is a [future-incompatible] lint to
-    /// transition this to a hard error in the future. See [issue #50504] for
-    /// more details.
-    ///
-    /// [issue #50504]: https://github.com/rust-lang/rust/issues/50504
-    /// [future-incompatible]: ../index.md#future-incompatible-lints
-    pub PROC_MACRO_DERIVE_RESOLUTION_FALLBACK,
-    Deny,
-    "detects proc macro derives using inaccessible names from parent modules",
-    @future_incompatible = FutureIncompatibleInfo {
-        reference: "issue #83583 <https://github.com/rust-lang/rust/issues/83583>",
-        reason: FutureIncompatibilityReason::FutureReleaseErrorReportNow,
-    };
-}
-
 declare_lint! {
     /// The `macro_use_extern_crate` lint detects the use of the
     /// [`macro_use` attribute].
@@ -3287,7 +3220,6 @@ declare_lint_pass! {
         UNSTABLE_NAME_COLLISIONS,
         IRREFUTABLE_LET_PATTERNS,
         WHERE_CLAUSES_OBJECT_SAFETY,
-        PROC_MACRO_DERIVE_RESOLUTION_FALLBACK,
         MACRO_USE_EXTERN_CRATE,
         MACRO_EXPANDED_MACRO_EXPORTS_ACCESSED_BY_ABSOLUTE_PATHS,
         ILL_FORMED_ATTRIBUTE_INPUT,
diff --git a/compiler/rustc_llvm/build.rs b/compiler/rustc_llvm/build.rs
index 28e092c1eb72..d35e4191cc0b 100644
--- a/compiler/rustc_llvm/build.rs
+++ b/compiler/rustc_llvm/build.rs
@@ -334,7 +334,7 @@ fn main() {
         "c++"
     } else if target.contains("netbsd") && llvm_static_stdcpp.is_some() {
         // NetBSD uses a separate library when relocation is required
-        "stdc++_pic"
+        "stdc++_p"
     } else if llvm_use_libcxx.is_some() {
         "c++"
     } else {
diff --git a/compiler/rustc_llvm/llvm-wrapper/LLVMWrapper.h b/compiler/rustc_llvm/llvm-wrapper/LLVMWrapper.h
index 015c1c52bef7..727cfc4416ee 100644
--- a/compiler/rustc_llvm/llvm-wrapper/LLVMWrapper.h
+++ b/compiler/rustc_llvm/llvm-wrapper/LLVMWrapper.h
@@ -76,7 +76,6 @@ enum LLVMRustAttribute {
   OptimizeNone = 24,
   ReturnsTwice = 25,
   ReadNone = 26,
-  InaccessibleMemOnly = 27,
   SanitizeHWAddress = 28,
   WillReturn = 29,
   StackProtectReq = 30,
diff --git a/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
index 879a3b660b4b..18d37d95a835 100644
--- a/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
@@ -69,7 +69,9 @@ extern "C" void LLVMInitializePasses() {
   initializeAnalysis(Registry);
   initializeTransformUtils(Registry);
   initializeInstCombine(Registry);
+#if LLVM_VERSION_LT(16, 0)
   initializeInstrumentation(Registry);
+#endif
   initializeTarget(Registry);
 }
 
diff --git a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
index 6f36281af23c..85c520a7911f 100644
--- a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
@@ -8,6 +8,9 @@
 #include "llvm/IR/Intrinsics.h"
 #include "llvm/IR/IntrinsicsARM.h"
 #include "llvm/IR/Mangler.h"
+#if LLVM_VERSION_GE(16, 0)
+#include "llvm/Support/ModRef.h"
+#endif
 #include "llvm/Object/Archive.h"
 #include "llvm/Object/COFFImportFile.h"
 #include "llvm/Object/ObjectFile.h"
@@ -213,8 +216,6 @@ static Attribute::AttrKind fromRust(LLVMRustAttribute Kind) {
     return Attribute::ReturnsTwice;
   case ReadNone:
     return Attribute::ReadNone;
-  case InaccessibleMemOnly:
-    return Attribute::InaccessibleMemOnly;
   case SanitizeHWAddress:
     return Attribute::SanitizeHWAddress;
   case WillReturn:
@@ -379,6 +380,43 @@ extern "C" LLVMAttributeRef LLVMRustCreateAllocKindAttr(LLVMContextRef C, uint64
 #endif
 }
 
+// Simplified representation of `MemoryEffects` across the FFI boundary.
+//
+// Each variant corresponds to one of the static factory methods on `MemoryEffects`.
+enum class LLVMRustMemoryEffects {
+  None,
+  ReadOnly,
+  InaccessibleMemOnly,
+};
+
+extern "C" LLVMAttributeRef LLVMRustCreateMemoryEffectsAttr(LLVMContextRef C,
+                                                            LLVMRustMemoryEffects Effects) {
+#if LLVM_VERSION_GE(16, 0)
+  switch (Effects) {
+    case LLVMRustMemoryEffects::None:
+      return wrap(Attribute::getWithMemoryEffects(*unwrap(C), MemoryEffects::none()));
+    case LLVMRustMemoryEffects::ReadOnly:
+      return wrap(Attribute::getWithMemoryEffects(*unwrap(C), MemoryEffects::readOnly()));
+    case LLVMRustMemoryEffects::InaccessibleMemOnly:
+      return wrap(Attribute::getWithMemoryEffects(*unwrap(C),
+                                                  MemoryEffects::inaccessibleMemOnly()));
+    default:
+      report_fatal_error("bad MemoryEffects.");
+  }
+#else
+  switch (Effects) {
+    case LLVMRustMemoryEffects::None:
+      return wrap(Attribute::get(*unwrap(C), Attribute::ReadNone));
+    case LLVMRustMemoryEffects::ReadOnly:
+      return wrap(Attribute::get(*unwrap(C), Attribute::ReadOnly));
+    case LLVMRustMemoryEffects::InaccessibleMemOnly:
+      return wrap(Attribute::get(*unwrap(C), Attribute::InaccessibleMemOnly));
+    default:
+      report_fatal_error("bad MemoryEffects.");
+  }
+#endif
+}
+
 // Enable a fast-math flag
 //
 // https://llvm.org/docs/LangRef.html#fast-math-flags
diff --git a/compiler/rustc_macros/src/diagnostics/diagnostic.rs b/compiler/rustc_macros/src/diagnostics/diagnostic.rs
index ef1985b960e3..ab38a9ccc8f8 100644
--- a/compiler/rustc_macros/src/diagnostics/diagnostic.rs
+++ b/compiler/rustc_macros/src/diagnostics/diagnostic.rs
@@ -69,6 +69,8 @@ impl<'a> DiagnosticDerive<'a> {
                     for @Self
                 where G: rustc_errors::EmissionGuarantee
             {
+
+                #[track_caller]
                 fn into_diagnostic(
                     self,
                     #handler: &'__diagnostic_handler_sess rustc_errors::Handler
@@ -133,6 +135,7 @@ impl<'a> LintDiagnosticDerive<'a> {
         let diag = &builder.diag;
         structure.gen_impl(quote! {
             gen impl<'__a> rustc_errors::DecorateLint<'__a, ()> for @Self {
+                #[track_caller]
                 fn decorate_lint<'__b>(
                     self,
                     #diag: &'__b mut rustc_errors::DiagnosticBuilder<'__a, ()>
diff --git a/compiler/rustc_macros/src/diagnostics/diagnostic_builder.rs b/compiler/rustc_macros/src/diagnostics/diagnostic_builder.rs
index 9f7d2661a3e8..3ea83fd09c79 100644
--- a/compiler/rustc_macros/src/diagnostics/diagnostic_builder.rs
+++ b/compiler/rustc_macros/src/diagnostics/diagnostic_builder.rs
@@ -454,7 +454,7 @@ impl<'a> DiagnosticDeriveVariantBuilder<'a> {
 
                 self.formatting_init.extend(code_init);
                 Ok(quote! {
-                    #diag.span_suggestion_with_style(
+                    #diag.span_suggestions_with_style(
                         #span_field,
                         rustc_errors::fluent::#slug,
                         #code_field,
diff --git a/compiler/rustc_macros/src/diagnostics/error.rs b/compiler/rustc_macros/src/diagnostics/error.rs
index 0b1ededa7751..4612f54e4b17 100644
--- a/compiler/rustc_macros/src/diagnostics/error.rs
+++ b/compiler/rustc_macros/src/diagnostics/error.rs
@@ -84,7 +84,7 @@ pub(crate) fn invalid_attr(attr: &Attribute, meta: &Meta) -> Diagnostic {
     }
 }
 
-/// Emit a error diagnostic for an invalid attribute (optionally performing additional decoration
+/// Emit an error diagnostic for an invalid attribute (optionally performing additional decoration
 /// using the `FnOnce` passed in `diag`) and return `Err(ErrorHandled)`.
 ///
 /// For methods that return a `Result<_, DiagnosticDeriveError>`:
@@ -126,7 +126,7 @@ pub(crate) fn invalid_nested_attr(attr: &Attribute, nested: &NestedMeta) -> Diag
     }
 }
 
-/// Emit a error diagnostic for an invalid nested attribute (optionally performing additional
+/// Emit an error diagnostic for an invalid nested attribute (optionally performing additional
 /// decoration using the `FnOnce` passed in `diag`) and return `Err(ErrorHandled)`.
 ///
 /// For methods that return a `Result<_, DiagnosticDeriveError>`:
diff --git a/compiler/rustc_macros/src/diagnostics/mod.rs b/compiler/rustc_macros/src/diagnostics/mod.rs
index 860340b43906..78df0cd1d341 100644
--- a/compiler/rustc_macros/src/diagnostics/mod.rs
+++ b/compiler/rustc_macros/src/diagnostics/mod.rs
@@ -129,7 +129,7 @@ pub fn lint_diagnostic_derive(s: Structure<'_>) -> TokenStream {
 /// }
 ///
 /// #[derive(Subdiagnostic)]
-/// #[suggestion_verbose(parser::raw_identifier)]
+/// #[suggestion(style = "verbose",parser::raw_identifier)]
 /// pub struct RawIdentifierSuggestion<'tcx> {
 ///     #[primary_span]
 ///     span: Span,
diff --git a/compiler/rustc_macros/src/diagnostics/subdiagnostic.rs b/compiler/rustc_macros/src/diagnostics/subdiagnostic.rs
index d1acb7138422..fa0ca5a52423 100644
--- a/compiler/rustc_macros/src/diagnostics/subdiagnostic.rs
+++ b/compiler/rustc_macros/src/diagnostics/subdiagnostic.rs
@@ -11,9 +11,11 @@ use crate::diagnostics::utils::{
 };
 use proc_macro2::TokenStream;
 use quote::{format_ident, quote};
-use syn::{spanned::Spanned, Attribute, Meta, MetaList, MetaNameValue, NestedMeta, Path};
+use syn::{spanned::Spanned, Attribute, Meta, MetaList, NestedMeta, Path};
 use synstructure::{BindingInfo, Structure, VariantInfo};
 
+use super::utils::{build_suggestion_code, AllowMultipleAlternatives};
+
 /// The central struct for constructing the `add_to_diagnostic` method from an annotated struct.
 pub(crate) struct SubdiagnosticDeriveBuilder {
     diag: syn::Ident,
@@ -414,15 +416,16 @@ impl<'parent, 'a> SubdiagnosticDeriveVariantBuilder<'parent, 'a> {
                     let nested_name = meta.path().segments.last().unwrap().ident.to_string();
                     let nested_name = nested_name.as_str();
 
-                    let Meta::NameValue(MetaNameValue { lit: syn::Lit::Str(value), .. }) = meta else {
-                        throw_invalid_nested_attr!(attr, &nested_attr);
-                    };
-
                     match nested_name {
                         "code" => {
-                            let formatted_str = self.build_format(&value.value(), value.span());
                             let code_field = new_code_ident();
-                            code.set_once((code_field, formatted_str), span);
+                            let formatting_init = build_suggestion_code(
+                                &code_field,
+                                meta,
+                                self,
+                                AllowMultipleAlternatives::No,
+                            );
+                            code.set_once((code_field, formatting_init), span);
                         }
                         _ => throw_invalid_nested_attr!(attr, &nested_attr, |diag| {
                             diag.help("`code` is the only valid nested attribute")
@@ -430,14 +433,14 @@ impl<'parent, 'a> SubdiagnosticDeriveVariantBuilder<'parent, 'a> {
                     }
                 }
 
-                let Some((code_field, formatted_str)) = code.value() else {
+                let Some((code_field, formatting_init)) = code.value() else {
                     span_err(span, "`#[suggestion_part(...)]` attribute without `code = \"...\"`")
                         .emit();
                     return Ok(quote! {});
                 };
                 let binding = info.binding;
 
-                self.formatting_init.extend(quote! { let #code_field = #formatted_str; });
+                self.formatting_init.extend(formatting_init);
                 let code_field = if clone_suggestion_code {
                     quote! { #code_field.clone() }
                 } else {
diff --git a/compiler/rustc_macros/src/diagnostics/utils.rs b/compiler/rustc_macros/src/diagnostics/utils.rs
index 61d5007fc30f..ba06f61299f3 100644
--- a/compiler/rustc_macros/src/diagnostics/utils.rs
+++ b/compiler/rustc_macros/src/diagnostics/utils.rs
@@ -2,7 +2,7 @@ use crate::diagnostics::error::{
     span_err, throw_invalid_attr, throw_invalid_nested_attr, throw_span_err, DiagnosticDeriveError,
 };
 use proc_macro::Span;
-use proc_macro2::TokenStream;
+use proc_macro2::{Ident, TokenStream};
 use quote::{format_ident, quote, ToTokens};
 use std::cell::RefCell;
 use std::collections::{BTreeSet, HashMap};
@@ -12,7 +12,7 @@ use syn::{spanned::Spanned, Attribute, Field, Meta, Type, TypeTuple};
 use syn::{MetaList, MetaNameValue, NestedMeta, Path};
 use synstructure::{BindingInfo, VariantInfo};
 
-use super::error::invalid_nested_attr;
+use super::error::{invalid_attr, invalid_nested_attr};
 
 thread_local! {
     pub static CODE_IDENT_COUNT: RefCell<u32> = RefCell::new(0);
@@ -395,17 +395,90 @@ pub(super) fn build_field_mapping<'v>(variant: &VariantInfo<'v>) -> HashMap<Stri
     fields_map
 }
 
+#[derive(Copy, Clone, Debug)]
+pub(super) enum AllowMultipleAlternatives {
+    No,
+    Yes,
+}
+
+/// Constructs the `format!()` invocation(s) necessary for a `#[suggestion*(code = "foo")]` or
+/// `#[suggestion*(code("foo", "bar"))]` attribute field
+pub(super) fn build_suggestion_code(
+    code_field: &Ident,
+    meta: &Meta,
+    fields: &impl HasFieldMap,
+    allow_multiple: AllowMultipleAlternatives,
+) -> TokenStream {
+    let values = match meta {
+        // `code = "foo"`
+        Meta::NameValue(MetaNameValue { lit: syn::Lit::Str(s), .. }) => vec![s],
+        // `code("foo", "bar")`
+        Meta::List(MetaList { nested, .. }) => {
+            if let AllowMultipleAlternatives::No = allow_multiple {
+                span_err(
+                    meta.span().unwrap(),
+                    "expected exactly one string literal for `code = ...`",
+                )
+                .emit();
+                vec![]
+            } else if nested.is_empty() {
+                span_err(
+                    meta.span().unwrap(),
+                    "expected at least one string literal for `code(...)`",
+                )
+                .emit();
+                vec![]
+            } else {
+                nested
+                    .into_iter()
+                    .filter_map(|item| {
+                        if let NestedMeta::Lit(syn::Lit::Str(s)) = item {
+                            Some(s)
+                        } else {
+                            span_err(
+                                item.span().unwrap(),
+                                "`code(...)` must contain only string literals",
+                            )
+                            .emit();
+                            None
+                        }
+                    })
+                    .collect()
+            }
+        }
+        _ => {
+            span_err(
+                meta.span().unwrap(),
+                r#"`code = "..."`/`code(...)` must contain only string literals"#,
+            )
+            .emit();
+            vec![]
+        }
+    };
+
+    if let AllowMultipleAlternatives::Yes = allow_multiple {
+        let formatted_strings: Vec<_> = values
+            .into_iter()
+            .map(|value| fields.build_format(&value.value(), value.span()))
+            .collect();
+        quote! { let #code_field = [#(#formatted_strings),*].into_iter(); }
+    } else if let [value] = values.as_slice() {
+        let formatted_str = fields.build_format(&value.value(), value.span());
+        quote! { let #code_field = #formatted_str; }
+    } else {
+        // error handled previously
+        quote! { let #code_field = String::new(); }
+    }
+}
+
 /// Possible styles for suggestion subdiagnostics.
-#[derive(Clone, Copy)]
+#[derive(Clone, Copy, PartialEq)]
 pub(super) enum SuggestionKind {
-    /// `#[suggestion]`
     Normal,
-    /// `#[suggestion_short]`
     Short,
-    /// `#[suggestion_hidden]`
     Hidden,
-    /// `#[suggestion_verbose]`
     Verbose,
+    ToolOnly,
 }
 
 impl FromStr for SuggestionKind {
@@ -413,15 +486,28 @@ impl FromStr for SuggestionKind {
 
     fn from_str(s: &str) -> Result<Self, Self::Err> {
         match s {
-            "" => Ok(SuggestionKind::Normal),
-            "_short" => Ok(SuggestionKind::Short),
-            "_hidden" => Ok(SuggestionKind::Hidden),
-            "_verbose" => Ok(SuggestionKind::Verbose),
+            "normal" => Ok(SuggestionKind::Normal),
+            "short" => Ok(SuggestionKind::Short),
+            "hidden" => Ok(SuggestionKind::Hidden),
+            "verbose" => Ok(SuggestionKind::Verbose),
+            "tool-only" => Ok(SuggestionKind::ToolOnly),
             _ => Err(()),
         }
     }
 }
 
+impl fmt::Display for SuggestionKind {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            SuggestionKind::Normal => write!(f, "normal"),
+            SuggestionKind::Short => write!(f, "short"),
+            SuggestionKind::Hidden => write!(f, "hidden"),
+            SuggestionKind::Verbose => write!(f, "verbose"),
+            SuggestionKind::ToolOnly => write!(f, "tool-only"),
+        }
+    }
+}
+
 impl SuggestionKind {
     pub fn to_suggestion_style(&self) -> TokenStream {
         match self {
@@ -437,6 +523,19 @@ impl SuggestionKind {
             SuggestionKind::Verbose => {
                 quote! { rustc_errors::SuggestionStyle::ShowAlways }
             }
+            SuggestionKind::ToolOnly => {
+                quote! { rustc_errors::SuggestionStyle::CompletelyHidden }
+            }
+        }
+    }
+
+    fn from_suffix(s: &str) -> Option<Self> {
+        match s {
+            "" => Some(SuggestionKind::Normal),
+            "_short" => Some(SuggestionKind::Short),
+            "_hidden" => Some(SuggestionKind::Hidden),
+            "_verbose" => Some(SuggestionKind::Verbose),
+            _ => None,
         }
     }
 }
@@ -489,25 +588,49 @@ impl SubdiagnosticKind {
         let name = name.as_str();
 
         let meta = attr.parse_meta()?;
+
         let mut kind = match name {
             "label" => SubdiagnosticKind::Label,
             "note" => SubdiagnosticKind::Note,
             "help" => SubdiagnosticKind::Help,
             "warning" => SubdiagnosticKind::Warn,
             _ => {
+                // Recover old `#[(multipart_)suggestion_*]` syntaxes
+                // FIXME(#100717): remove
                 if let Some(suggestion_kind) =
-                    name.strip_prefix("suggestion").and_then(|s| s.parse().ok())
+                    name.strip_prefix("suggestion").and_then(SuggestionKind::from_suffix)
                 {
+                    if suggestion_kind != SuggestionKind::Normal {
+                        invalid_attr(attr, &meta)
+                            .help(format!(
+                                r#"Use `#[suggestion(..., style = "{}")]` instead"#,
+                                suggestion_kind
+                            ))
+                            .emit();
+                    }
+
                     SubdiagnosticKind::Suggestion {
-                        suggestion_kind,
+                        suggestion_kind: SuggestionKind::Normal,
                         applicability: None,
                         code_field: new_code_ident(),
                         code_init: TokenStream::new(),
                     }
                 } else if let Some(suggestion_kind) =
-                    name.strip_prefix("multipart_suggestion").and_then(|s| s.parse().ok())
+                    name.strip_prefix("multipart_suggestion").and_then(SuggestionKind::from_suffix)
                 {
-                    SubdiagnosticKind::MultipartSuggestion { suggestion_kind, applicability: None }
+                    if suggestion_kind != SuggestionKind::Normal {
+                        invalid_attr(attr, &meta)
+                            .help(format!(
+                                r#"Use `#[multipart_suggestion(..., style = "{}")]` instead"#,
+                                suggestion_kind
+                            ))
+                            .emit();
+                    }
+
+                    SubdiagnosticKind::MultipartSuggestion {
+                        suggestion_kind: SuggestionKind::Normal,
+                        applicability: None,
+                    }
                 } else {
                     throw_invalid_attr!(attr, &meta);
                 }
@@ -545,6 +668,7 @@ impl SubdiagnosticKind {
         };
 
         let mut code = None;
+        let mut suggestion_kind = None;
 
         let mut nested_iter = nested.into_iter().peekable();
 
@@ -571,21 +695,23 @@ impl SubdiagnosticKind {
             let nested_name = meta.path().segments.last().unwrap().ident.to_string();
             let nested_name = nested_name.as_str();
 
-            let value = match meta {
-                Meta::NameValue(MetaNameValue { lit: syn::Lit::Str(value), .. }) => value,
+            let string_value = match meta {
+                Meta::NameValue(MetaNameValue { lit: syn::Lit::Str(value), .. }) => Some(value),
+
                 Meta::Path(_) => throw_invalid_nested_attr!(attr, &nested_attr, |diag| {
                     diag.help("a diagnostic slug must be the first argument to the attribute")
                 }),
-                _ => {
-                    invalid_nested_attr(attr, &nested_attr).emit();
-                    continue;
-                }
+                _ => None,
             };
 
             match (nested_name, &mut kind) {
                 ("code", SubdiagnosticKind::Suggestion { code_field, .. }) => {
-                    let formatted_str = fields.build_format(&value.value(), value.span());
-                    let code_init = quote! { let #code_field = #formatted_str; };
+                    let code_init = build_suggestion_code(
+                        code_field,
+                        meta,
+                        fields,
+                        AllowMultipleAlternatives::Yes,
+                    );
                     code.set_once(code_init, span);
                 }
                 (
@@ -593,22 +719,48 @@ impl SubdiagnosticKind {
                     SubdiagnosticKind::Suggestion { ref mut applicability, .. }
                     | SubdiagnosticKind::MultipartSuggestion { ref mut applicability, .. },
                 ) => {
+                    let Some(value) = string_value else {
+                        invalid_nested_attr(attr, &nested_attr).emit();
+                        continue;
+                    };
+
                     let value = Applicability::from_str(&value.value()).unwrap_or_else(|()| {
                         span_err(span, "invalid applicability").emit();
                         Applicability::Unspecified
                     });
                     applicability.set_once(value, span);
                 }
+                (
+                    "style",
+                    SubdiagnosticKind::Suggestion { .. }
+                    | SubdiagnosticKind::MultipartSuggestion { .. },
+                ) => {
+                    let Some(value) = string_value else {
+                        invalid_nested_attr(attr, &nested_attr).emit();
+                        continue;
+                    };
+
+                    let value = value.value().parse().unwrap_or_else(|()| {
+                        span_err(value.span().unwrap(), "invalid suggestion style")
+                            .help("valid styles are `normal`, `short`, `hidden`, `verbose` and `tool-only`")
+                            .emit();
+                        SuggestionKind::Normal
+                    });
+
+                    suggestion_kind.set_once(value, span);
+                }
 
                 // Invalid nested attribute
                 (_, SubdiagnosticKind::Suggestion { .. }) => {
                     invalid_nested_attr(attr, &nested_attr)
-                        .help("only `code` and `applicability` are valid nested attributes")
+                        .help(
+                            "only `style`, `code` and `applicability` are valid nested attributes",
+                        )
                         .emit();
                 }
                 (_, SubdiagnosticKind::MultipartSuggestion { .. }) => {
                     invalid_nested_attr(attr, &nested_attr)
-                        .help("only `applicability` is a valid nested attributes")
+                        .help("only `style` and `applicability` are valid nested attributes")
                         .emit()
                 }
                 _ => {
@@ -618,19 +770,34 @@ impl SubdiagnosticKind {
         }
 
         match kind {
-            SubdiagnosticKind::Suggestion { ref code_field, ref mut code_init, .. } => {
+            SubdiagnosticKind::Suggestion {
+                ref code_field,
+                ref mut code_init,
+                suggestion_kind: ref mut kind_field,
+                ..
+            } => {
+                if let Some(kind) = suggestion_kind.value() {
+                    *kind_field = kind;
+                }
+
                 *code_init = if let Some(init) = code.value() {
                     init
                 } else {
                     span_err(span, "suggestion without `code = \"...\"`").emit();
-                    quote! { let #code_field: String = unreachable!(); }
+                    quote! { let #code_field = std::iter::empty(); }
                 };
             }
+            SubdiagnosticKind::MultipartSuggestion {
+                suggestion_kind: ref mut kind_field, ..
+            } => {
+                if let Some(kind) = suggestion_kind.value() {
+                    *kind_field = kind;
+                }
+            }
             SubdiagnosticKind::Label
             | SubdiagnosticKind::Note
             | SubdiagnosticKind::Help
-            | SubdiagnosticKind::Warn
-            | SubdiagnosticKind::MultipartSuggestion { .. } => {}
+            | SubdiagnosticKind::Warn => {}
         }
 
         Ok(Some((kind, slug)))
@@ -644,7 +811,7 @@ impl quote::IdentFragment for SubdiagnosticKind {
             SubdiagnosticKind::Note => write!(f, "note"),
             SubdiagnosticKind::Help => write!(f, "help"),
             SubdiagnosticKind::Warn => write!(f, "warn"),
-            SubdiagnosticKind::Suggestion { .. } => write!(f, "suggestion_with_style"),
+            SubdiagnosticKind::Suggestion { .. } => write!(f, "suggestions_with_style"),
             SubdiagnosticKind::MultipartSuggestion { .. } => {
                 write!(f, "multipart_suggestion_with_style")
             }
diff --git a/compiler/rustc_metadata/src/creader.rs b/compiler/rustc_metadata/src/creader.rs
index cfcceecbef40..d4c457975a84 100644
--- a/compiler/rustc_metadata/src/creader.rs
+++ b/compiler/rustc_metadata/src/creader.rs
@@ -1,8 +1,10 @@
 //! Validates all used crates and extern libraries and loads their metadata
 
 use crate::errors::{
-    ConflictingGlobalAlloc, CrateNotPanicRuntime, GlobalAllocRequired, NoMultipleGlobalAlloc,
-    NoPanicStrategy, NoTransitiveNeedsDep, NotProfilerRuntime, ProfilerBuiltinsNeedsCore,
+    AllocFuncRequired, ConflictingAllocErrorHandler, ConflictingGlobalAlloc, CrateNotPanicRuntime,
+    GlobalAllocRequired, MissingAllocErrorHandler, NoMultipleAllocErrorHandler,
+    NoMultipleGlobalAlloc, NoPanicStrategy, NoTransitiveNeedsDep, NotProfilerRuntime,
+    ProfilerBuiltinsNeedsCore,
 };
 use crate::locator::{CrateError, CrateLocator, CratePaths};
 use crate::rmeta::{CrateDep, CrateMetadata, CrateNumMap, CrateRoot, MetadataBlob};
@@ -41,8 +43,13 @@ pub struct CStore {
     /// This crate needs an allocator and either provides it itself, or finds it in a dependency.
     /// If the above is true, then this field denotes the kind of the found allocator.
     allocator_kind: Option<AllocatorKind>,
+    /// This crate needs an allocation error handler and either provides it itself, or finds it in a dependency.
+    /// If the above is true, then this field denotes the kind of the found allocator.
+    alloc_error_handler_kind: Option<AllocatorKind>,
     /// This crate has a `#[global_allocator]` item.
     has_global_allocator: bool,
+    /// This crate has a `#[alloc_error_handler]` item.
+    has_alloc_error_handler: bool,
 
     /// This map is used to verify we get no hash conflicts between
     /// `StableCrateId` values.
@@ -197,10 +204,18 @@ impl CStore {
         self.allocator_kind
     }
 
+    pub(crate) fn alloc_error_handler_kind(&self) -> Option<AllocatorKind> {
+        self.alloc_error_handler_kind
+    }
+
     pub(crate) fn has_global_allocator(&self) -> bool {
         self.has_global_allocator
     }
 
+    pub(crate) fn has_alloc_error_handler(&self) -> bool {
+        self.has_alloc_error_handler
+    }
+
     pub fn report_unused_deps(&self, tcx: TyCtxt<'_>) {
         let json_unused_externs = tcx.sess.opts.json_unused_externs;
 
@@ -247,7 +262,9 @@ impl<'a> CrateLoader<'a> {
                 metas: IndexVec::from_elem_n(None, 1),
                 injected_panic_runtime: None,
                 allocator_kind: None,
+                alloc_error_handler_kind: None,
                 has_global_allocator: false,
+                has_alloc_error_handler: false,
                 stable_crate_ids,
                 unused_externs: Vec::new(),
             },
@@ -792,6 +809,13 @@ impl<'a> CrateLoader<'a> {
             }
             spans => !spans.is_empty(),
         };
+        self.cstore.has_alloc_error_handler = match &*alloc_error_handler_spans(&self.sess, krate) {
+            [span1, span2, ..] => {
+                self.sess.emit_err(NoMultipleAllocErrorHandler { span2: *span2, span1: *span1 });
+                true
+            }
+            spans => !spans.is_empty(),
+        };
 
         // Check to see if we actually need an allocator. This desire comes
         // about through the `#![needs_allocator]` attribute and is typically
@@ -832,22 +856,48 @@ impl<'a> CrateLoader<'a> {
                 }
             }
         }
+        let mut alloc_error_handler =
+            self.cstore.has_alloc_error_handler.then(|| Symbol::intern("this crate"));
+        for (_, data) in self.cstore.iter_crate_data() {
+            if data.has_alloc_error_handler() {
+                match alloc_error_handler {
+                    Some(other_crate) => {
+                        self.sess.emit_err(ConflictingAllocErrorHandler {
+                            crate_name: data.name(),
+                            other_crate_name: other_crate,
+                        });
+                    }
+                    None => alloc_error_handler = Some(data.name()),
+                }
+            }
+        }
 
         if global_allocator.is_some() {
             self.cstore.allocator_kind = Some(AllocatorKind::Global);
-            return;
+        } else {
+            // Ok we haven't found a global allocator but we still need an
+            // allocator. At this point our allocator request is typically fulfilled
+            // by the standard library, denoted by the `#![default_lib_allocator]`
+            // attribute.
+            if !self.sess.contains_name(&krate.attrs, sym::default_lib_allocator)
+                && !self.cstore.iter_crate_data().any(|(_, data)| data.has_default_lib_allocator())
+            {
+                self.sess.emit_err(GlobalAllocRequired);
+            }
+            self.cstore.allocator_kind = Some(AllocatorKind::Default);
         }
 
-        // Ok we haven't found a global allocator but we still need an
-        // allocator. At this point our allocator request is typically fulfilled
-        // by the standard library, denoted by the `#![default_lib_allocator]`
-        // attribute.
-        if !self.sess.contains_name(&krate.attrs, sym::default_lib_allocator)
-            && !self.cstore.iter_crate_data().any(|(_, data)| data.has_default_lib_allocator())
-        {
-            self.sess.emit_err(GlobalAllocRequired);
+        if alloc_error_handler.is_some() {
+            self.cstore.alloc_error_handler_kind = Some(AllocatorKind::Global);
+        } else {
+            // The alloc crate provides a default allocation error handler if
+            // one isn't specified.
+            if !self.sess.features_untracked().default_alloc_error_handler {
+                self.sess.emit_err(AllocFuncRequired);
+                self.sess.emit_note(MissingAllocErrorHandler);
+            }
+            self.cstore.alloc_error_handler_kind = Some(AllocatorKind::Default);
         }
-        self.cstore.allocator_kind = Some(AllocatorKind::Default);
     }
 
     fn inject_dependency_if(
@@ -1023,3 +1073,26 @@ fn global_allocator_spans(sess: &Session, krate: &ast::Crate) -> Vec<Span> {
     visit::walk_crate(&mut f, krate);
     f.spans
 }
+
+fn alloc_error_handler_spans(sess: &Session, krate: &ast::Crate) -> Vec<Span> {
+    struct Finder<'a> {
+        sess: &'a Session,
+        name: Symbol,
+        spans: Vec<Span>,
+    }
+    impl<'ast, 'a> visit::Visitor<'ast> for Finder<'a> {
+        fn visit_item(&mut self, item: &'ast ast::Item) {
+            if item.ident.name == self.name
+                && self.sess.contains_name(&item.attrs, sym::rustc_std_internal_symbol)
+            {
+                self.spans.push(item.span);
+            }
+            visit::walk_item(self, item)
+        }
+    }
+
+    let name = Symbol::intern(&AllocatorKind::Global.fn_name(sym::oom));
+    let mut f = Finder { sess, name, spans: Vec::new() };
+    visit::walk_crate(&mut f, krate);
+    f.spans
+}
diff --git a/compiler/rustc_metadata/src/errors.rs b/compiler/rustc_metadata/src/errors.rs
index 7c387b9a9ecd..e5b91d566e52 100644
--- a/compiler/rustc_metadata/src/errors.rs
+++ b/compiler/rustc_metadata/src/errors.rs
@@ -343,6 +343,16 @@ pub struct NoMultipleGlobalAlloc {
     pub span1: Span,
 }
 
+#[derive(Diagnostic)]
+#[diag(metadata_no_multiple_alloc_error_handler)]
+pub struct NoMultipleAllocErrorHandler {
+    #[primary_span]
+    #[label]
+    pub span2: Span,
+    #[label(metadata_prev_alloc_error_handler)]
+    pub span1: Span,
+}
+
 #[derive(Diagnostic)]
 #[diag(metadata_conflicting_global_alloc)]
 pub struct ConflictingGlobalAlloc {
@@ -350,10 +360,25 @@ pub struct ConflictingGlobalAlloc {
     pub other_crate_name: Symbol,
 }
 
+#[derive(Diagnostic)]
+#[diag(metadata_conflicting_alloc_error_handler)]
+pub struct ConflictingAllocErrorHandler {
+    pub crate_name: Symbol,
+    pub other_crate_name: Symbol,
+}
+
 #[derive(Diagnostic)]
 #[diag(metadata_global_alloc_required)]
 pub struct GlobalAllocRequired;
 
+#[derive(Diagnostic)]
+#[diag(metadata_alloc_func_required)]
+pub struct AllocFuncRequired;
+
+#[derive(Diagnostic)]
+#[diag(metadata_missing_alloc_error_handler)]
+pub struct MissingAllocErrorHandler;
+
 #[derive(Diagnostic)]
 #[diag(metadata_no_transitive_needs_dep)]
 pub struct NoTransitiveNeedsDep<'a> {
@@ -578,6 +603,7 @@ pub struct InvalidMetadataFiles {
 }
 
 impl IntoDiagnostic<'_> for InvalidMetadataFiles {
+    #[track_caller]
     fn into_diagnostic(
         self,
         handler: &'_ rustc_errors::Handler,
@@ -606,6 +632,7 @@ pub struct CannotFindCrate {
 }
 
 impl IntoDiagnostic<'_> for CannotFindCrate {
+    #[track_caller]
     fn into_diagnostic(
         self,
         handler: &'_ rustc_errors::Handler,
diff --git a/compiler/rustc_metadata/src/foreign_modules.rs b/compiler/rustc_metadata/src/foreign_modules.rs
index 2ca4cd17fdf0..d1c2f3104d07 100644
--- a/compiler/rustc_metadata/src/foreign_modules.rs
+++ b/compiler/rustc_metadata/src/foreign_modules.rs
@@ -6,13 +6,13 @@ use rustc_session::cstore::ForeignModule;
 pub(crate) fn collect(tcx: TyCtxt<'_>) -> Vec<ForeignModule> {
     let mut modules = Vec::new();
     for id in tcx.hir().items() {
-        if !matches!(tcx.def_kind(id.def_id), DefKind::ForeignMod) {
+        if !matches!(tcx.def_kind(id.owner_id), DefKind::ForeignMod) {
             continue;
         }
         let item = tcx.hir().item(id);
         if let hir::ItemKind::ForeignMod { items, .. } = item.kind {
-            let foreign_items = items.iter().map(|it| it.id.def_id.to_def_id()).collect();
-            modules.push(ForeignModule { foreign_items, def_id: id.def_id.to_def_id() });
+            let foreign_items = items.iter().map(|it| it.id.owner_id.to_def_id()).collect();
+            modules.push(ForeignModule { foreign_items, def_id: id.owner_id.to_def_id() });
         }
     }
     modules
diff --git a/compiler/rustc_metadata/src/fs.rs b/compiler/rustc_metadata/src/fs.rs
index f360a586476e..c41ae8d55cda 100644
--- a/compiler/rustc_metadata/src/fs.rs
+++ b/compiler/rustc_metadata/src/fs.rs
@@ -22,9 +22,14 @@ pub const METADATA_FILENAME: &str = "lib.rmeta";
 /// building an `.rlib` (stomping over one another), or writing an `.rmeta` into a
 /// directory being searched for `extern crate` (observing an incomplete file).
 /// The returned path is the temporary file containing the complete metadata.
-pub fn emit_metadata(sess: &Session, metadata: &[u8], tmpdir: &MaybeTempDir) -> PathBuf {
-    let out_filename = tmpdir.as_ref().join(METADATA_FILENAME);
-    let result = fs::write(&out_filename, metadata);
+pub fn emit_wrapper_file(
+    sess: &Session,
+    data: &[u8],
+    tmpdir: &MaybeTempDir,
+    name: &str,
+) -> PathBuf {
+    let out_filename = tmpdir.as_ref().join(name);
+    let result = fs::write(&out_filename, data);
 
     if let Err(err) = result {
         sess.emit_fatal(FailedWriteError { filename: out_filename, err });
diff --git a/compiler/rustc_metadata/src/lib.rs b/compiler/rustc_metadata/src/lib.rs
index 98cf6fef54a8..1987f88e6b8c 100644
--- a/compiler/rustc_metadata/src/lib.rs
+++ b/compiler/rustc_metadata/src/lib.rs
@@ -41,6 +41,6 @@ pub mod errors;
 pub mod fs;
 pub mod locator;
 
-pub use fs::{emit_metadata, METADATA_FILENAME};
+pub use fs::{emit_wrapper_file, METADATA_FILENAME};
 pub use native_libs::find_native_static_library;
 pub use rmeta::{encode_metadata, EncodedMetadata, METADATA_HEADER};
diff --git a/compiler/rustc_metadata/src/native_libs.rs b/compiler/rustc_metadata/src/native_libs.rs
index 676c67bad827..20a2e78299ae 100644
--- a/compiler/rustc_metadata/src/native_libs.rs
+++ b/compiler/rustc_metadata/src/native_libs.rs
@@ -98,7 +98,7 @@ struct Collector<'tcx> {
 
 impl<'tcx> Collector<'tcx> {
     fn process_item(&mut self, id: rustc_hir::ItemId) {
-        if !matches!(self.tcx.def_kind(id.def_id), DefKind::ForeignMod) {
+        if !matches!(self.tcx.def_kind(id.owner_id), DefKind::ForeignMod) {
             return;
         }
 
@@ -372,17 +372,17 @@ impl<'tcx> Collector<'tcx> {
                 }
                 _ => {
                     for child_item in foreign_mod_items {
-                        if self.tcx.def_kind(child_item.id.def_id).has_codegen_attrs()
+                        if self.tcx.def_kind(child_item.id.owner_id).has_codegen_attrs()
                             && self
                                 .tcx
-                                .codegen_fn_attrs(child_item.id.def_id)
+                                .codegen_fn_attrs(child_item.id.owner_id)
                                 .link_ordinal
                                 .is_some()
                         {
                             let link_ordinal_attr = self
                                 .tcx
                                 .hir()
-                                .attrs(child_item.id.def_id.into())
+                                .attrs(child_item.id.owner_id.into())
                                 .iter()
                                 .find(|a| a.has_name(sym::link_ordinal))
                                 .unwrap();
@@ -402,7 +402,7 @@ impl<'tcx> Collector<'tcx> {
                 filename,
                 kind,
                 cfg,
-                foreign_module: Some(it.def_id.to_def_id()),
+                foreign_module: Some(it.owner_id.to_def_id()),
                 wasm_import_module: wasm_import_module.map(|(name, _)| name),
                 verbatim,
                 dll_imports,
@@ -505,7 +505,7 @@ impl<'tcx> Collector<'tcx> {
     fn i686_arg_list_size(&self, item: &hir::ForeignItemRef) -> usize {
         let argument_types: &List<Ty<'_>> = self.tcx.erase_late_bound_regions(
             self.tcx
-                .type_of(item.id.def_id)
+                .type_of(item.id.owner_id)
                 .fn_sig(self.tcx)
                 .inputs()
                 .map_bound(|slice| self.tcx.mk_type_list(slice.iter())),
@@ -557,7 +557,7 @@ impl<'tcx> Collector<'tcx> {
             }
         };
 
-        let codegen_fn_attrs = self.tcx.codegen_fn_attrs(item.id.def_id);
+        let codegen_fn_attrs = self.tcx.codegen_fn_attrs(item.id.owner_id);
         let import_name_type = codegen_fn_attrs
             .link_ordinal
             .map_or(import_name_type, |ord| Some(PeImportNameType::Ordinal(ord)));
@@ -567,7 +567,7 @@ impl<'tcx> Collector<'tcx> {
             import_name_type,
             calling_convention,
             span: item.span,
-            is_fn: self.tcx.def_kind(item.id.def_id).is_fn_like(),
+            is_fn: self.tcx.def_kind(item.id.owner_id).is_fn_like(),
         }
     }
 }
diff --git a/compiler/rustc_metadata/src/rmeta/decoder.rs b/compiler/rustc_metadata/src/rmeta/decoder.rs
index 830417eea1a0..8e80d794a136 100644
--- a/compiler/rustc_metadata/src/rmeta/decoder.rs
+++ b/compiler/rustc_metadata/src/rmeta/decoder.rs
@@ -15,7 +15,6 @@ use rustc_hir::def::{CtorKind, CtorOf, DefKind, Res};
 use rustc_hir::def_id::{CrateNum, DefId, DefIndex, CRATE_DEF_INDEX, LOCAL_CRATE};
 use rustc_hir::definitions::{DefKey, DefPath, DefPathData, DefPathHash};
 use rustc_hir::diagnostic_items::DiagnosticItems;
-use rustc_hir::lang_items;
 use rustc_index::vec::{Idx, IndexVec};
 use rustc_middle::metadata::ModChild;
 use rustc_middle::middle::exported_symbols::{ExportedSymbol, SymbolExportInfo};
@@ -773,7 +772,15 @@ impl<'a, 'tcx> CrateMetadataRef<'a> {
     }
 
     fn opt_item_name(self, item_index: DefIndex) -> Option<Symbol> {
-        self.def_key(item_index).disambiguated_data.data.get_opt_name()
+        let def_key = self.def_key(item_index);
+        def_key.disambiguated_data.data.get_opt_name().or_else(|| {
+            if def_key.disambiguated_data.data == DefPathData::Ctor {
+                let parent_index = def_key.parent.expect("no parent for a constructor");
+                self.def_key(parent_index).disambiguated_data.data.get_opt_name()
+            } else {
+                None
+            }
+        })
     }
 
     fn item_name(self, item_index: DefIndex) -> Symbol {
@@ -905,7 +912,13 @@ impl<'a, 'tcx> CrateMetadataRef<'a> {
                 .get(self, item_id)
                 .unwrap_or_else(LazyArray::empty)
                 .decode(self)
-                .map(|index| self.get_variant(&self.def_kind(index), index, did))
+                .filter_map(|index| {
+                    let kind = self.def_kind(index);
+                    match kind {
+                        DefKind::Ctor(..) => None,
+                        _ => Some(self.get_variant(&kind, index, did)),
+                    }
+                })
                 .collect()
         } else {
             std::iter::once(self.get_variant(&kind, item_id, did)).collect()
@@ -953,7 +966,7 @@ impl<'a, 'tcx> CrateMetadataRef<'a> {
     }
 
     /// Iterates over the language items in the given crate.
-    fn get_lang_items(self, tcx: TyCtxt<'tcx>) -> &'tcx [(DefId, usize)] {
+    fn get_lang_items(self, tcx: TyCtxt<'tcx>) -> &'tcx [(DefId, LangItem)] {
         tcx.arena.alloc_from_iter(
             self.root
                 .lang_items
@@ -1029,50 +1042,27 @@ impl<'a, 'tcx> CrateMetadataRef<'a> {
 
                 callback(ModChild { ident, res, vis, span, macro_rules });
 
-                // For non-re-export structs and variants add their constructors to children.
-                // Re-export lists automatically contain constructors when necessary.
-                match kind {
-                    DefKind::Struct => {
-                        if let Some((ctor_def_id, ctor_kind)) =
-                            self.get_ctor_def_id_and_kind(child_index)
-                        {
-                            let ctor_res =
-                                Res::Def(DefKind::Ctor(CtorOf::Struct, ctor_kind), ctor_def_id);
-                            let vis = self.get_visibility(ctor_def_id.index);
-                            callback(ModChild {
-                                ident,
-                                res: ctor_res,
-                                vis,
-                                span,
-                                macro_rules: false,
-                            });
+                // For non-reexport variants add their fictive constructors to children.
+                // Braced variants, unlike structs, generate unusable names in value namespace,
+                // they are reserved for possible future use. It's ok to use the variant's id as
+                // a ctor id since an error will be reported on any use of such resolution anyway.
+                // Reexport lists automatically contain such constructors when necessary.
+                if kind == DefKind::Variant && self.get_ctor_def_id_and_kind(child_index).is_none()
+                {
+                    let ctor_res =
+                        Res::Def(DefKind::Ctor(CtorOf::Variant, CtorKind::Fictive), def_id);
+                    let mut vis = vis;
+                    if vis.is_public() {
+                        // For non-exhaustive variants lower the constructor visibility to
+                        // within the crate. We only need this for fictive constructors,
+                        // for other constructors correct visibilities
+                        // were already encoded in metadata.
+                        let mut attrs = self.get_item_attrs(def_id.index, sess);
+                        if attrs.any(|item| item.has_name(sym::non_exhaustive)) {
+                            vis = ty::Visibility::Restricted(self.local_def_id(CRATE_DEF_INDEX));
                         }
                     }
-                    DefKind::Variant => {
-                        // Braced variants, unlike structs, generate unusable names in
-                        // value namespace, they are reserved for possible future use.
-                        // It's ok to use the variant's id as a ctor id since an
-                        // error will be reported on any use of such resolution anyway.
-                        let (ctor_def_id, ctor_kind) = self
-                            .get_ctor_def_id_and_kind(child_index)
-                            .unwrap_or((def_id, CtorKind::Fictive));
-                        let ctor_res =
-                            Res::Def(DefKind::Ctor(CtorOf::Variant, ctor_kind), ctor_def_id);
-                        let mut vis = self.get_visibility(ctor_def_id.index);
-                        if ctor_def_id == def_id && vis.is_public() {
-                            // For non-exhaustive variants lower the constructor visibility to
-                            // within the crate. We only need this for fictive constructors,
-                            // for other constructors correct visibilities
-                            // were already encoded in metadata.
-                            let mut attrs = self.get_item_attrs(def_id.index, sess);
-                            if attrs.any(|item| item.has_name(sym::non_exhaustive)) {
-                                let crate_def_id = self.local_def_id(CRATE_DEF_INDEX);
-                                vis = ty::Visibility::Restricted(crate_def_id);
-                            }
-                        }
-                        callback(ModChild { ident, res: ctor_res, vis, span, macro_rules: false });
-                    }
-                    _ => {}
+                    callback(ModChild { ident, res: ctor_res, vis, span, macro_rules: false });
                 }
             }
         }
@@ -1328,7 +1318,7 @@ impl<'a, 'tcx> CrateMetadataRef<'a> {
         )
     }
 
-    fn get_missing_lang_items(self, tcx: TyCtxt<'tcx>) -> &'tcx [lang_items::LangItem] {
+    fn get_missing_lang_items(self, tcx: TyCtxt<'tcx>) -> &'tcx [LangItem] {
         tcx.arena.alloc_from_iter(self.root.lang_items_missing.decode(self))
     }
 
@@ -1774,6 +1764,10 @@ impl CrateMetadata {
         self.root.has_global_allocator
     }
 
+    pub(crate) fn has_alloc_error_handler(&self) -> bool {
+        self.root.has_alloc_error_handler
+    }
+
     pub(crate) fn has_default_lib_allocator(&self) -> bool {
         self.root.has_default_lib_allocator
     }
diff --git a/compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs b/compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs
index a0a0855251b8..f475b0b39811 100644
--- a/compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs
+++ b/compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs
@@ -255,6 +255,7 @@ provide! { tcx, def_id, other, cdata,
     is_panic_runtime => { cdata.root.panic_runtime }
     is_compiler_builtins => { cdata.root.compiler_builtins }
     has_global_allocator => { cdata.root.has_global_allocator }
+    has_alloc_error_handler => { cdata.root.has_alloc_error_handler }
     has_panic_handler => { cdata.root.has_panic_handler }
     is_profiler_runtime => { cdata.root.profiler_runtime }
     required_panic_strategy => { cdata.root.required_panic_strategy }
@@ -339,6 +340,7 @@ pub(in crate::rmeta) fn provide(providers: &mut Providers) {
     // resolve! Does this work? Unsure! That's what the issue is about
     *providers = Providers {
         allocator_kind: |tcx, ()| CStore::from_tcx(tcx).allocator_kind(),
+        alloc_error_handler_kind: |tcx, ()| CStore::from_tcx(tcx).alloc_error_handler_kind(),
         is_private_dep: |_tcx, cnum| {
             assert_eq!(cnum, LOCAL_CRATE);
             false
@@ -464,6 +466,10 @@ pub(in crate::rmeta) fn provide(providers: &mut Providers) {
             assert_eq!(cnum, LOCAL_CRATE);
             CStore::from_tcx(tcx).has_global_allocator()
         },
+        has_alloc_error_handler: |tcx, cnum| {
+            assert_eq!(cnum, LOCAL_CRATE);
+            CStore::from_tcx(tcx).has_alloc_error_handler()
+        },
         postorder_cnums: |tcx, ()| {
             tcx.arena
                 .alloc_slice(&CStore::from_tcx(tcx).crate_dependencies_in_postorder(LOCAL_CRATE))
diff --git a/compiler/rustc_metadata/src/rmeta/encoder.rs b/compiler/rustc_metadata/src/rmeta/encoder.rs
index c019211a948e..6a73e14e9f58 100644
--- a/compiler/rustc_metadata/src/rmeta/encoder.rs
+++ b/compiler/rustc_metadata/src/rmeta/encoder.rs
@@ -17,7 +17,7 @@ use rustc_hir::def_id::{
 };
 use rustc_hir::definitions::DefPathData;
 use rustc_hir::intravisit::{self, Visitor};
-use rustc_hir::lang_items;
+use rustc_hir::lang_items::LangItem;
 use rustc_middle::hir::nested_filter;
 use rustc_middle::middle::dependency_format::Linkage;
 use rustc_middle::middle::exported_symbols::{
@@ -670,6 +670,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
                 panic_in_drop_strategy: tcx.sess.opts.unstable_opts.panic_in_drop,
                 edition: tcx.sess.edition(),
                 has_global_allocator: tcx.has_global_allocator(LOCAL_CRATE),
+                has_alloc_error_handler: tcx.has_alloc_error_handler(LOCAL_CRATE),
                 has_panic_handler: tcx.has_panic_handler(LOCAL_CRATE),
                 has_default_lib_allocator: tcx
                     .sess
@@ -787,9 +788,7 @@ fn should_encode_attr(
     } else if attr.doc_str().is_some() {
         // We keep all public doc comments because they might be "imported" into downstream crates
         // if they use `#[doc(inline)]` to copy an item's documentation into their own.
-        *is_def_id_public.get_or_insert_with(|| {
-            tcx.privacy_access_levels(()).get_effective_vis(def_id).is_some()
-        })
+        *is_def_id_public.get_or_insert_with(|| tcx.effective_visibilities(()).is_exported(def_id))
     } else if attr.has_name(sym::doc) {
         // If this is a `doc` attribute, and it's marked `inline` (as in `#[doc(inline)]`), we can
         // remove it. It won't be inlinable in downstream crates.
@@ -1094,43 +1093,6 @@ fn should_encode_const(def_kind: DefKind) -> bool {
     }
 }
 
-fn should_encode_constness(def_kind: DefKind) -> bool {
-    match def_kind {
-        DefKind::Struct
-        | DefKind::Union
-        | DefKind::Enum
-        | DefKind::Trait
-        | DefKind::AssocTy
-        | DefKind::Fn
-        | DefKind::Const
-        | DefKind::Static(..)
-        | DefKind::Ctor(..)
-        | DefKind::AssocFn
-        | DefKind::AssocConst
-        | DefKind::AnonConst
-        | DefKind::InlineConst
-        | DefKind::OpaqueTy
-        | DefKind::ImplTraitPlaceholder
-        | DefKind::Impl
-        | DefKind::Closure
-        | DefKind::Generator
-        | DefKind::TyAlias => true,
-        DefKind::Variant
-        | DefKind::TraitAlias
-        | DefKind::ForeignTy
-        | DefKind::Field
-        | DefKind::TyParam
-        | DefKind::Mod
-        | DefKind::ForeignMod
-        | DefKind::ConstParam
-        | DefKind::Macro(..)
-        | DefKind::Use
-        | DefKind::LifetimeParam
-        | DefKind::GlobalAsm
-        | DefKind::ExternCrate => false,
-    }
-}
-
 fn should_encode_trait_impl_trait_tys<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> bool {
     if tcx.def_kind(def_id) != DefKind::AssocFn {
         return false;
@@ -1239,9 +1201,6 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
             {
                 record!(self.tables.trait_impl_trait_tys[def_id] <- table);
             }
-            if should_encode_constness(def_kind) {
-                self.tables.constness.set(def_id.index, tcx.constness(def_id));
-            }
         }
         let inherent_impls = tcx.crate_inherent_impls(());
         for (def_id, implementations) in inherent_impls.inherent_impls.iter() {
@@ -1269,6 +1228,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
         };
 
         record!(self.tables.variant_data[def_id] <- data);
+        self.tables.constness.set(def_id.index, hir::Constness::Const);
         record_array!(self.tables.children[def_id] <- variant.fields.iter().map(|f| {
             assert!(f.did.is_local());
             f.did.index
@@ -1296,6 +1256,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
         };
 
         record!(self.tables.variant_data[def_id] <- data);
+        self.tables.constness.set(def_id.index, hir::Constness::Const);
         if variant.ctor_kind == CtorKind::Fn {
             record!(self.tables.fn_sig[def_id] <- tcx.fn_sig(def_id));
         }
@@ -1329,14 +1290,21 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
                         // from name resolution point of view.
                         hir::ItemKind::ForeignMod { items, .. } => {
                             for foreign_item in items {
-                                yield foreign_item.id.def_id.def_id.local_def_index;
+                                yield foreign_item.id.owner_id.def_id.local_def_index;
                             }
                         }
                         // Only encode named non-reexport children, reexports are encoded
                         // separately and unnamed items are not used by name resolution.
                         hir::ItemKind::ExternCrate(..) => continue,
-                        _ if tcx.def_key(item_id.def_id.to_def_id()).get_opt_name().is_some() => {
-                            yield item_id.def_id.def_id.local_def_index;
+                        hir::ItemKind::Struct(ref vdata, _) => {
+                            yield item_id.owner_id.def_id.local_def_index;
+                            // Encode constructors which take a separate slot in value namespace.
+                            if let Some(ctor_hir_id) = vdata.ctor_hir_id() {
+                                yield tcx.hir().local_def_id(ctor_hir_id).local_def_index;
+                            }
+                        }
+                        _ if tcx.def_key(item_id.owner_id.to_def_id()).get_opt_name().is_some() => {
+                            yield item_id.owner_id.def_id.local_def_index;
                         }
                         _ => continue,
                     }
@@ -1359,6 +1327,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
 
         record!(self.tables.repr_options[def_id] <- adt_def.repr());
         record!(self.tables.variant_data[def_id] <- data);
+        self.tables.constness.set(def_id.index, hir::Constness::Const);
         if variant.ctor_kind == CtorKind::Fn {
             record!(self.tables.fn_sig[def_id] <- tcx.fn_sig(def_id));
         }
@@ -1394,6 +1363,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
                     }
                 };
                 self.tables.asyncness.set(def_id.index, m_sig.header.asyncness);
+                self.tables.constness.set(def_id.index, hir::Constness::NotConst);
             }
             ty::AssocKind::Type => {
                 self.encode_explicit_item_bounds(def_id);
@@ -1418,6 +1388,13 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
                 let hir::ImplItemKind::Fn(ref sig, body) = ast_item.kind else { bug!() };
                 self.tables.asyncness.set(def_id.index, sig.header.asyncness);
                 record_array!(self.tables.fn_arg_names[def_id] <- self.tcx.hir().body_param_names(body));
+                // Can be inside `impl const Trait`, so using sig.header.constness is not reliable
+                let constness = if self.tcx.is_const_fn_raw(def_id) {
+                    hir::Constness::Const
+                } else {
+                    hir::Constness::NotConst
+                };
+                self.tables.constness.set(def_id.index, constness);
             }
             ty::AssocKind::Const | ty::AssocKind::Type => {}
         }
@@ -1555,6 +1532,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
             hir::ItemKind::Fn(ref sig, .., body) => {
                 self.tables.asyncness.set(def_id.index, sig.header.asyncness);
                 record_array!(self.tables.fn_arg_names[def_id] <- self.tcx.hir().body_param_names(body));
+                self.tables.constness.set(def_id.index, sig.header.constness);
             }
             hir::ItemKind::Macro(ref macro_def, _) => {
                 if macro_def.macro_rules {
@@ -1563,7 +1541,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
                 record!(self.tables.macro_definition[def_id] <- &*macro_def.body);
             }
             hir::ItemKind::Mod(ref m) => {
-                return self.encode_info_for_mod(item.def_id.def_id, m);
+                return self.encode_info_for_mod(item.owner_id.def_id, m);
             }
             hir::ItemKind::OpaqueTy(..) => {
                 self.encode_explicit_item_bounds(def_id);
@@ -1575,6 +1553,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
             hir::ItemKind::Struct(ref struct_def, _) => {
                 let adt_def = self.tcx.adt_def(def_id);
                 record!(self.tables.repr_options[def_id] <- adt_def.repr());
+                self.tables.constness.set(def_id.index, hir::Constness::Const);
 
                 // Encode def_ids for each field and method
                 // for methods, write all the stuff get_trait_method
@@ -1603,8 +1582,9 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
                     is_non_exhaustive: variant.is_field_list_non_exhaustive(),
                 });
             }
-            hir::ItemKind::Impl(hir::Impl { defaultness, .. }) => {
+            hir::ItemKind::Impl(hir::Impl { defaultness, constness, .. }) => {
                 self.tables.impl_defaultness.set(def_id.index, *defaultness);
+                self.tables.constness.set(def_id.index, *constness);
 
                 let trait_ref = self.tcx.impl_trait_ref(def_id);
                 if let Some(trait_ref) = trait_ref {
@@ -1646,12 +1626,17 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
         };
         // FIXME(eddyb) there should be a nicer way to do this.
         match item.kind {
-            hir::ItemKind::Enum(..) => record_array!(self.tables.children[def_id] <-
-                self.tcx.adt_def(def_id).variants().iter().map(|v| {
-                    assert!(v.def_id.is_local());
-                    v.def_id.index
-                })
-            ),
+            hir::ItemKind::Enum(..) => {
+                record_array!(self.tables.children[def_id] <- iter::from_generator(||
+                    for variant in tcx.adt_def(def_id).variants() {
+                        yield variant.def_id.index;
+                        // Encode constructors which take a separate slot in value namespace.
+                        if let Some(ctor_def_id) = variant.ctor_def_id {
+                            yield ctor_def_id.index;
+                        }
+                    }
+                ))
+            }
             hir::ItemKind::Struct(..) | hir::ItemKind::Union(..) => {
                 record_array!(self.tables.children[def_id] <-
                     self.tcx.adt_def(def_id).non_enum_variant().fields.iter().map(|f| {
@@ -1688,7 +1673,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
         // normally in the visitor walk.
         match item.kind {
             hir::ItemKind::Enum(..) => {
-                let def = self.tcx.adt_def(item.def_id.to_def_id());
+                let def = self.tcx.adt_def(item.owner_id.to_def_id());
                 for (i, variant) in def.variants().iter_enumerated() {
                     self.encode_enum_variant_info(def, i);
 
@@ -1698,7 +1683,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
                 }
             }
             hir::ItemKind::Struct(ref struct_def, _) => {
-                let def = self.tcx.adt_def(item.def_id.to_def_id());
+                let def = self.tcx.adt_def(item.owner_id.to_def_id());
                 // If the struct has a constructor, encode it.
                 if let Some(ctor_hir_id) = struct_def.ctor_hir_id() {
                     let ctor_def_id = self.tcx.hir().local_def_id(ctor_hir_id);
@@ -1707,13 +1692,14 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
             }
             hir::ItemKind::Impl { .. } => {
                 for &trait_item_def_id in
-                    self.tcx.associated_item_def_ids(item.def_id.to_def_id()).iter()
+                    self.tcx.associated_item_def_ids(item.owner_id.to_def_id()).iter()
                 {
                     self.encode_info_for_impl_item(trait_item_def_id);
                 }
             }
             hir::ItemKind::Trait(..) => {
-                for &item_def_id in self.tcx.associated_item_def_ids(item.def_id.to_def_id()).iter()
+                for &item_def_id in
+                    self.tcx.associated_item_def_ids(item.owner_id.to_def_id()).iter()
                 {
                     self.encode_info_for_trait_item(item_def_id);
                 }
@@ -1919,22 +1905,15 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
         self.lazy_array(diagnostic_items.iter().map(|(&name, def_id)| (name, def_id.index)))
     }
 
-    fn encode_lang_items(&mut self) -> LazyArray<(DefIndex, usize)> {
+    fn encode_lang_items(&mut self) -> LazyArray<(DefIndex, LangItem)> {
         empty_proc_macro!(self);
-        let tcx = self.tcx;
-        let lang_items = tcx.lang_items();
-        let lang_items = lang_items.items().iter();
-        self.lazy_array(lang_items.enumerate().filter_map(|(i, &opt_def_id)| {
-            if let Some(def_id) = opt_def_id {
-                if def_id.is_local() {
-                    return Some((def_id.index, i));
-                }
-            }
-            None
+        let lang_items = self.tcx.lang_items().iter();
+        self.lazy_array(lang_items.filter_map(|(lang_item, def_id)| {
+            def_id.as_local().map(|id| (id.local_def_index, lang_item))
         }))
     }
 
-    fn encode_lang_items_missing(&mut self) -> LazyArray<lang_items::LangItem> {
+    fn encode_lang_items_missing(&mut self) -> LazyArray<LangItem> {
         empty_proc_macro!(self);
         let tcx = self.tcx;
         self.lazy_array(&tcx.lang_items().missing)
@@ -1954,8 +1933,8 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
             FxHashMap::default();
 
         for id in tcx.hir().items() {
-            if matches!(tcx.def_kind(id.def_id), DefKind::Impl) {
-                if let Some(trait_ref) = tcx.impl_trait_ref(id.def_id) {
+            if matches!(tcx.def_kind(id.owner_id), DefKind::Impl) {
+                if let Some(trait_ref) = tcx.impl_trait_ref(id.owner_id) {
                     let simplified_self_ty = fast_reject::simplify_type(
                         self.tcx,
                         trait_ref.self_ty(),
@@ -1965,7 +1944,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
                     fx_hash_map
                         .entry(trait_ref.def_id)
                         .or_default()
-                        .push((id.def_id.def_id.local_def_index, simplified_self_ty));
+                        .push((id.owner_id.def_id.local_def_index, simplified_self_ty));
                 }
             }
         }
@@ -2106,12 +2085,12 @@ impl<'a, 'tcx> Visitor<'tcx> for EncodeContext<'a, 'tcx> {
         intravisit::walk_item(self, item);
         match item.kind {
             hir::ItemKind::ExternCrate(_) | hir::ItemKind::Use(..) => {} // ignore these
-            _ => self.encode_info_for_item(item.def_id.to_def_id(), item),
+            _ => self.encode_info_for_item(item.owner_id.to_def_id(), item),
         }
     }
     fn visit_foreign_item(&mut self, ni: &'tcx hir::ForeignItem<'tcx>) {
         intravisit::walk_foreign_item(self, ni);
-        self.encode_info_for_foreign_item(ni.def_id.to_def_id(), ni);
+        self.encode_info_for_foreign_item(ni.owner_id.to_def_id(), ni);
     }
     fn visit_generics(&mut self, generics: &'tcx hir::Generics<'tcx>) {
         intravisit::walk_generics(self, generics);
@@ -2330,8 +2309,8 @@ pub fn provide(providers: &mut Providers) {
 
             let mut traits = Vec::new();
             for id in tcx.hir().items() {
-                if matches!(tcx.def_kind(id.def_id), DefKind::Trait | DefKind::TraitAlias) {
-                    traits.push(id.def_id.to_def_id())
+                if matches!(tcx.def_kind(id.owner_id), DefKind::Trait | DefKind::TraitAlias) {
+                    traits.push(id.owner_id.to_def_id())
                 }
             }
 
diff --git a/compiler/rustc_metadata/src/rmeta/mod.rs b/compiler/rustc_metadata/src/rmeta/mod.rs
index 27dc8ff16ac5..aa6d378a43ac 100644
--- a/compiler/rustc_metadata/src/rmeta/mod.rs
+++ b/compiler/rustc_metadata/src/rmeta/mod.rs
@@ -12,7 +12,7 @@ use rustc_hir as hir;
 use rustc_hir::def::{CtorKind, DefKind};
 use rustc_hir::def_id::{CrateNum, DefId, DefIndex, DefPathHash, StableCrateId};
 use rustc_hir::definitions::DefKey;
-use rustc_hir::lang_items;
+use rustc_hir::lang_items::LangItem;
 use rustc_index::bit_set::{BitSet, FiniteBitSet};
 use rustc_index::vec::IndexVec;
 use rustc_middle::metadata::ModChild;
@@ -223,6 +223,7 @@ pub(crate) struct CrateRoot {
     panic_in_drop_strategy: PanicStrategy,
     edition: Edition,
     has_global_allocator: bool,
+    has_alloc_error_handler: bool,
     has_panic_handler: bool,
     has_default_lib_allocator: bool,
 
@@ -230,8 +231,8 @@ pub(crate) struct CrateRoot {
     dylib_dependency_formats: LazyArray<Option<LinkagePreference>>,
     lib_features: LazyArray<(Symbol, Option<Symbol>)>,
     stability_implications: LazyArray<(Symbol, Symbol)>,
-    lang_items: LazyArray<(DefIndex, usize)>,
-    lang_items_missing: LazyArray<lang_items::LangItem>,
+    lang_items: LazyArray<(DefIndex, LangItem)>,
+    lang_items_missing: LazyArray<LangItem>,
     diagnostic_items: LazyArray<(Symbol, DefIndex)>,
     native_libraries: LazyArray<NativeLib>,
     foreign_modules: LazyArray<ForeignModule>,
diff --git a/compiler/rustc_middle/Cargo.toml b/compiler/rustc_middle/Cargo.toml
index de916ea8c497..5f6e498dbeaa 100644
--- a/compiler/rustc_middle/Cargo.toml
+++ b/compiler/rustc_middle/Cargo.toml
@@ -8,7 +8,7 @@ doctest = false
 
 [dependencies]
 bitflags = "1.2.1"
-chalk-ir = "0.80.0"
+chalk-ir = "0.87.0"
 either = "1.5.0"
 gsgdt = "0.1.2"
 polonius-engine = "0.13.0"
@@ -32,7 +32,7 @@ rustc_span = { path = "../rustc_span" }
 rustc_target = { path = "../rustc_target" }
 rustc_type_ir = { path = "../rustc_type_ir" }
 smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
-thin-vec = "0.2.8"
+thin-vec = "0.2.9"
 tracing = "0.1"
 
 [features]
diff --git a/compiler/rustc_middle/src/arena.rs b/compiler/rustc_middle/src/arena.rs
index d2847e4bc12a..f8aae86fe3dc 100644
--- a/compiler/rustc_middle/src/arena.rs
+++ b/compiler/rustc_middle/src/arena.rs
@@ -77,7 +77,7 @@ macro_rules! arena_types {
                     rustc_middle::infer::canonical::QueryResponse<'tcx, rustc_middle::ty::Ty<'tcx>>
                 >,
             [] all_traits: Vec<rustc_hir::def_id::DefId>,
-            [] privacy_access_levels: rustc_middle::middle::privacy::AccessLevels,
+            [] effective_visibilities: rustc_middle::middle::privacy::EffectiveVisibilities,
             [] foreign_module: rustc_session::cstore::ForeignModule,
             [] foreign_modules: Vec<rustc_session::cstore::ForeignModule>,
             [] upvars_mentioned: rustc_data_structures::fx::FxIndexMap<rustc_hir::HirId, rustc_hir::Upvar>,
@@ -96,7 +96,7 @@ macro_rules! arena_types {
             // since we need to allocate this type on both the `rustc_hir` arena
             // (during lowering) and the `librustc_middle` arena (for decoding MIR)
             [decode] asm_template: rustc_ast::InlineAsmTemplatePiece,
-            [decode] used_trait_imports: rustc_data_structures::fx::FxHashSet<rustc_hir::def_id::LocalDefId>,
+            [decode] used_trait_imports: rustc_data_structures::unord::UnordSet<rustc_hir::def_id::LocalDefId>,
             [decode] is_late_bound_map: rustc_data_structures::fx::FxIndexSet<rustc_hir::def_id::LocalDefId>,
             [decode] impl_source: rustc_middle::traits::ImplSource<'tcx, ()>,
 
diff --git a/compiler/rustc_middle/src/error.rs b/compiler/rustc_middle/src/error.rs
index a7a7ac0599d7..43903e6739f9 100644
--- a/compiler/rustc_middle/src/error.rs
+++ b/compiler/rustc_middle/src/error.rs
@@ -55,3 +55,12 @@ pub struct ConstEvalNonIntError {
     #[primary_span]
     pub span: Span,
 }
+
+#[derive(Diagnostic)]
+#[diag(middle_strict_coherence_needs_negative_coherence)]
+pub(crate) struct StrictCoherenceNeedsNegativeCoherence {
+    #[primary_span]
+    pub span: Span,
+    #[label]
+    pub attr_span: Option<Span>,
+}
diff --git a/compiler/rustc_middle/src/hir/map/mod.rs b/compiler/rustc_middle/src/hir/map/mod.rs
index 302f12a6f7d4..14f50ae87de0 100644
--- a/compiler/rustc_middle/src/hir/map/mod.rs
+++ b/compiler/rustc_middle/src/hir/map/mod.rs
@@ -353,20 +353,24 @@ impl<'hir> Map<'hir> {
         node.node.generics()
     }
 
+    pub fn owner(self, id: OwnerId) -> OwnerNode<'hir> {
+        self.tcx.hir_owner(id).unwrap_or_else(|| bug!("expected owner for {:?}", id)).node
+    }
+
     pub fn item(self, id: ItemId) -> &'hir Item<'hir> {
-        self.tcx.hir_owner(id.def_id).unwrap().node.expect_item()
+        self.tcx.hir_owner(id.owner_id).unwrap().node.expect_item()
     }
 
     pub fn trait_item(self, id: TraitItemId) -> &'hir TraitItem<'hir> {
-        self.tcx.hir_owner(id.def_id).unwrap().node.expect_trait_item()
+        self.tcx.hir_owner(id.owner_id).unwrap().node.expect_trait_item()
     }
 
     pub fn impl_item(self, id: ImplItemId) -> &'hir ImplItem<'hir> {
-        self.tcx.hir_owner(id.def_id).unwrap().node.expect_impl_item()
+        self.tcx.hir_owner(id.owner_id).unwrap().node.expect_impl_item()
     }
 
     pub fn foreign_item(self, id: ForeignItemId) -> &'hir ForeignItem<'hir> {
-        self.tcx.hir_owner(id.def_id).unwrap().node.expect_foreign_item()
+        self.tcx.hir_owner(id.owner_id).unwrap().node.expect_foreign_item()
     }
 
     pub fn body(self, id: BodyId) -> &'hir Body<'hir> {
@@ -822,8 +826,11 @@ impl<'hir> Map<'hir> {
         )
     }
 
-    pub fn expect_owner(self, id: OwnerId) -> OwnerNode<'hir> {
-        self.tcx.hir_owner(id).unwrap_or_else(|| bug!("expected owner for {:?}", id)).node
+    pub fn expect_owner(self, def_id: LocalDefId) -> OwnerNode<'hir> {
+        self.tcx
+            .hir_owner(OwnerId { def_id })
+            .unwrap_or_else(|| bug!("expected owner for {:?}", def_id))
+            .node
     }
 
     pub fn expect_item(self, id: LocalDefId) -> &'hir Item<'hir> {
@@ -1377,14 +1384,14 @@ impl<'hir> Visitor<'hir> for ItemCollector<'hir> {
 
     fn visit_item(&mut self, item: &'hir Item<'hir>) {
         if associated_body(Node::Item(item)).is_some() {
-            self.body_owners.push(item.def_id.def_id);
+            self.body_owners.push(item.owner_id.def_id);
         }
 
         self.items.push(item.item_id());
 
         // Items that are modules are handled here instead of in visit_mod.
         if let ItemKind::Mod(module) = &item.kind {
-            self.submodules.push(item.def_id);
+            self.submodules.push(item.owner_id);
             // A module collector does not recurse inside nested modules.
             if self.crate_collector {
                 intravisit::walk_mod(self, module, item.hir_id());
@@ -1413,7 +1420,7 @@ impl<'hir> Visitor<'hir> for ItemCollector<'hir> {
 
     fn visit_trait_item(&mut self, item: &'hir TraitItem<'hir>) {
         if associated_body(Node::TraitItem(item)).is_some() {
-            self.body_owners.push(item.def_id.def_id);
+            self.body_owners.push(item.owner_id.def_id);
         }
 
         self.trait_items.push(item.trait_item_id());
@@ -1422,7 +1429,7 @@ impl<'hir> Visitor<'hir> for ItemCollector<'hir> {
 
     fn visit_impl_item(&mut self, item: &'hir ImplItem<'hir>) {
         if associated_body(Node::ImplItem(item)).is_some() {
-            self.body_owners.push(item.def_id.def_id);
+            self.body_owners.push(item.owner_id.def_id);
         }
 
         self.impl_items.push(item.impl_item_id());
diff --git a/compiler/rustc_middle/src/hir/mod.rs b/compiler/rustc_middle/src/hir/mod.rs
index 1ce98a03c8a6..1c6264ad0365 100644
--- a/compiler/rustc_middle/src/hir/mod.rs
+++ b/compiler/rustc_middle/src/hir/mod.rs
@@ -67,10 +67,10 @@ impl ModuleItems {
     pub fn definitions(&self) -> impl Iterator<Item = LocalDefId> + '_ {
         self.items
             .iter()
-            .map(|id| id.def_id.def_id)
-            .chain(self.trait_items.iter().map(|id| id.def_id.def_id))
-            .chain(self.impl_items.iter().map(|id| id.def_id.def_id))
-            .chain(self.foreign_items.iter().map(|id| id.def_id.def_id))
+            .map(|id| id.owner_id.def_id)
+            .chain(self.trait_items.iter().map(|id| id.owner_id.def_id))
+            .chain(self.impl_items.iter().map(|id| id.owner_id.def_id))
+            .chain(self.foreign_items.iter().map(|id| id.owner_id.def_id))
     }
 
     pub fn par_items(&self, f: impl Fn(ItemId) + Send + Sync) {
diff --git a/compiler/rustc_middle/src/infer/canonical.rs b/compiler/rustc_middle/src/infer/canonical.rs
index f4f1d82c3b8d..0331d764b38a 100644
--- a/compiler/rustc_middle/src/infer/canonical.rs
+++ b/compiler/rustc_middle/src/infer/canonical.rs
@@ -302,8 +302,10 @@ impl<'tcx, V> Canonical<'tcx, V> {
     }
 }
 
-pub type QueryOutlivesConstraint<'tcx> =
-    (ty::Binder<'tcx, ty::OutlivesPredicate<GenericArg<'tcx>, Region<'tcx>>>, ConstraintCategory);
+pub type QueryOutlivesConstraint<'tcx> = (
+    ty::Binder<'tcx, ty::OutlivesPredicate<GenericArg<'tcx>, Region<'tcx>>>,
+    ConstraintCategory<'tcx>,
+);
 
 TrivialTypeTraversalAndLiftImpls! {
     for <'tcx> {
@@ -334,15 +336,17 @@ impl<'tcx> CanonicalVarValues<'tcx> {
                         tcx.mk_ty(ty::Bound(ty::INNERMOST, ty::BoundVar::from_u32(i).into())).into()
                     }
                     GenericArgKind::Lifetime(..) => {
-                        let br =
-                            ty::BoundRegion { var: ty::BoundVar::from_u32(i), kind: ty::BrAnon(i) };
+                        let br = ty::BoundRegion {
+                            var: ty::BoundVar::from_u32(i),
+                            kind: ty::BrAnon(i, None),
+                        };
                         tcx.mk_region(ty::ReLateBound(ty::INNERMOST, br)).into()
                     }
                     GenericArgKind::Const(ct) => tcx
-                        .mk_const(ty::ConstS {
-                            ty: ct.ty(),
-                            kind: ty::ConstKind::Bound(ty::INNERMOST, ty::BoundVar::from_u32(i)),
-                        })
+                        .mk_const(
+                            ty::ConstKind::Bound(ty::INNERMOST, ty::BoundVar::from_u32(i)),
+                            ct.ty(),
+                        )
                         .into(),
                 })
                 .collect(),
diff --git a/compiler/rustc_middle/src/lib.rs b/compiler/rustc_middle/src/lib.rs
index a58cbc3767ed..6bdf591fdd79 100644
--- a/compiler/rustc_middle/src/lib.rs
+++ b/compiler/rustc_middle/src/lib.rs
@@ -43,7 +43,6 @@
 #![feature(type_alias_impl_trait)]
 #![feature(associated_type_bounds)]
 #![feature(rustc_attrs)]
-#![cfg_attr(bootstrap, feature(half_open_range_patterns))]
 #![feature(control_flow_enum)]
 #![feature(associated_type_defaults)]
 #![feature(trusted_step)]
diff --git a/compiler/rustc_middle/src/lint.rs b/compiler/rustc_middle/src/lint.rs
index 79522bd0b2b2..51df42f6d14e 100644
--- a/compiler/rustc_middle/src/lint.rs
+++ b/compiler/rustc_middle/src/lint.rs
@@ -276,7 +276,7 @@ pub fn explain_lint_level_source(
 
 /// The innermost function for emitting lints.
 ///
-/// If you are loocking to implement a lint, look for higher level functions,
+/// If you are looking to implement a lint, look for higher level functions,
 /// for example:
 /// - [`TyCtxt::emit_spanned_lint`]
 /// - [`TyCtxt::struct_span_lint_hir`]
diff --git a/compiler/rustc_middle/src/middle/lang_items.rs b/compiler/rustc_middle/src/middle/lang_items.rs
index 31c20fa14aaf..dd4332d0db6d 100644
--- a/compiler/rustc_middle/src/middle/lang_items.rs
+++ b/compiler/rustc_middle/src/middle/lang_items.rs
@@ -36,10 +36,6 @@ impl<'tcx> TyCtxt<'tcx> {
             _ => None,
         }
     }
-
-    pub fn is_weak_lang_item(self, item_def_id: DefId) -> bool {
-        self.lang_items().is_weak_lang_item(item_def_id)
-    }
 }
 
 /// Returns `true` if the specified `lang_item` must be present for this
diff --git a/compiler/rustc_middle/src/middle/privacy.rs b/compiler/rustc_middle/src/middle/privacy.rs
index 556bd24d00f9..3a91522d3622 100644
--- a/compiler/rustc_middle/src/middle/privacy.rs
+++ b/compiler/rustc_middle/src/middle/privacy.rs
@@ -1,128 +1,110 @@
 //! A pass that checks to make sure private fields and methods aren't used
 //! outside their scopes. This pass will also generate a set of exported items
 //! which are available for use externally when compiled as a library.
-use crate::ty::{DefIdTree, Visibility};
+use crate::ty::{DefIdTree, TyCtxt, Visibility};
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
+use rustc_hir::def::DefKind;
 use rustc_macros::HashStable;
 use rustc_query_system::ich::StableHashingContext;
-use rustc_span::def_id::{DefId, LocalDefId};
+use rustc_span::def_id::LocalDefId;
 use std::hash::Hash;
 
-/// Represents the levels of accessibility an item can have.
+/// Represents the levels of effective visibility an item can have.
 ///
-/// The variants are sorted in ascending order of accessibility.
+/// The variants are sorted in ascending order of directness.
 #[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, HashStable)]
-pub enum AccessLevel {
-    /// Superset of `AccessLevel::Reachable` used to mark impl Trait items.
-    ReachableFromImplTrait,
-    /// Exported items + items participating in various kinds of public interfaces,
-    /// but not directly nameable. For example, if function `fn f() -> T {...}` is
-    /// public, then type `T` is reachable. Its values can be obtained by other crates
-    /// even if the type itself is not nameable.
+pub enum Level {
+    /// Superset of `Reachable` including items leaked through return position `impl Trait`.
+    ReachableThroughImplTrait,
+    /// Item is either reexported, or leaked through any kind of interface.
+    /// For example, if function `fn f() -> T {...}` is directly public, then type `T` is publicly
+    /// reachable and its values can be obtained by other crates even if the type itself is not
+    /// nameable.
     Reachable,
-    /// Public items + items accessible to other crates with the help of `pub use` re-exports.
-    Exported,
-    /// Items accessible to other crates directly, without the help of re-exports.
-    Public,
+    /// Item is accessible either directly, or with help of `use` reexports.
+    Reexported,
+    /// Item is directly accessible, without help of reexports.
+    Direct,
 }
 
-impl AccessLevel {
-    pub fn all_levels() -> [AccessLevel; 4] {
-        [
-            AccessLevel::Public,
-            AccessLevel::Exported,
-            AccessLevel::Reachable,
-            AccessLevel::ReachableFromImplTrait,
-        ]
+impl Level {
+    pub fn all_levels() -> [Level; 4] {
+        [Level::Direct, Level::Reexported, Level::Reachable, Level::ReachableThroughImplTrait]
     }
 }
 
 #[derive(Clone, Copy, PartialEq, Eq, Debug, HashStable)]
 pub struct EffectiveVisibility {
-    public: Visibility,
-    exported: Visibility,
+    direct: Visibility,
+    reexported: Visibility,
     reachable: Visibility,
-    reachable_from_impl_trait: Visibility,
+    reachable_through_impl_trait: Visibility,
 }
 
 impl EffectiveVisibility {
-    pub fn get(&self, tag: AccessLevel) -> &Visibility {
-        match tag {
-            AccessLevel::Public => &self.public,
-            AccessLevel::Exported => &self.exported,
-            AccessLevel::Reachable => &self.reachable,
-            AccessLevel::ReachableFromImplTrait => &self.reachable_from_impl_trait,
+    pub fn at_level(&self, level: Level) -> &Visibility {
+        match level {
+            Level::Direct => &self.direct,
+            Level::Reexported => &self.reexported,
+            Level::Reachable => &self.reachable,
+            Level::ReachableThroughImplTrait => &self.reachable_through_impl_trait,
         }
     }
 
-    fn get_mut(&mut self, tag: AccessLevel) -> &mut Visibility {
-        match tag {
-            AccessLevel::Public => &mut self.public,
-            AccessLevel::Exported => &mut self.exported,
-            AccessLevel::Reachable => &mut self.reachable,
-            AccessLevel::ReachableFromImplTrait => &mut self.reachable_from_impl_trait,
+    fn at_level_mut(&mut self, level: Level) -> &mut Visibility {
+        match level {
+            Level::Direct => &mut self.direct,
+            Level::Reexported => &mut self.reexported,
+            Level::Reachable => &mut self.reachable,
+            Level::ReachableThroughImplTrait => &mut self.reachable_through_impl_trait,
         }
     }
 
-    pub fn is_public_at_level(&self, tag: AccessLevel) -> bool {
-        self.get(tag).is_public()
+    pub fn is_public_at_level(&self, level: Level) -> bool {
+        self.at_level(level).is_public()
     }
 
-    fn update(&mut self, vis: Visibility, tag: AccessLevel, tree: impl DefIdTree) -> bool {
-        let mut changed = false;
-        for level in AccessLevel::all_levels() {
-            if level <= tag {
-                let current_effective_vis = self.get_mut(level);
-                if *current_effective_vis != vis && vis.is_at_least(*current_effective_vis, tree) {
-                    changed = true;
-                    *current_effective_vis = vis;
-                }
-            }
-        }
-        changed
-    }
-
-    fn from_vis(vis: Visibility) -> EffectiveVisibility {
+    pub fn from_vis(vis: Visibility) -> EffectiveVisibility {
         EffectiveVisibility {
-            public: vis,
-            exported: vis,
+            direct: vis,
+            reexported: vis,
             reachable: vis,
-            reachable_from_impl_trait: vis,
+            reachable_through_impl_trait: vis,
         }
     }
 }
 
-/// Holds a map of accessibility levels for reachable HIR nodes.
-#[derive(Debug, Clone)]
-pub struct AccessLevels<Id = LocalDefId> {
+/// Holds a map of effective visibilities for reachable HIR nodes.
+#[derive(Clone, Debug)]
+pub struct EffectiveVisibilities<Id = LocalDefId> {
     map: FxHashMap<Id, EffectiveVisibility>,
 }
 
-impl<Id: Hash + Eq + Copy> AccessLevels<Id> {
-    pub fn is_public_at_level(&self, id: Id, tag: AccessLevel) -> bool {
-        self.get_effective_vis(id)
-            .map_or(false, |effective_vis| effective_vis.is_public_at_level(tag))
+impl EffectiveVisibilities {
+    pub fn is_public_at_level(&self, id: LocalDefId, level: Level) -> bool {
+        self.effective_vis(id)
+            .map_or(false, |effective_vis| effective_vis.is_public_at_level(level))
     }
 
-    /// See `AccessLevel::Reachable`.
-    pub fn is_reachable(&self, id: Id) -> bool {
-        self.is_public_at_level(id, AccessLevel::Reachable)
+    /// See `Level::Reachable`.
+    pub fn is_reachable(&self, id: LocalDefId) -> bool {
+        self.is_public_at_level(id, Level::Reachable)
     }
 
-    /// See `AccessLevel::Exported`.
-    pub fn is_exported(&self, id: Id) -> bool {
-        self.is_public_at_level(id, AccessLevel::Exported)
+    /// See `Level::Reexported`.
+    pub fn is_exported(&self, id: LocalDefId) -> bool {
+        self.is_public_at_level(id, Level::Reexported)
     }
 
-    /// See `AccessLevel::Public`.
-    pub fn is_public(&self, id: Id) -> bool {
-        self.is_public_at_level(id, AccessLevel::Public)
+    /// See `Level::Direct`.
+    pub fn is_directly_public(&self, id: LocalDefId) -> bool {
+        self.is_public_at_level(id, Level::Direct)
     }
 
-    pub fn get_access_level(&self, id: Id) -> Option<AccessLevel> {
-        self.get_effective_vis(id).and_then(|effective_vis| {
-            for level in AccessLevel::all_levels() {
+    pub fn public_at_level(&self, id: LocalDefId) -> Option<Level> {
+        self.effective_vis(id).and_then(|effective_vis| {
+            for level in Level::all_levels() {
                 if effective_vis.is_public_at_level(level) {
                     return Some(level);
                 }
@@ -131,87 +113,172 @@ impl<Id: Hash + Eq + Copy> AccessLevels<Id> {
         })
     }
 
-    pub fn get_effective_vis(&self, id: Id) -> Option<&EffectiveVisibility> {
-        self.map.get(&id)
-    }
-
-    pub fn iter(&self) -> impl Iterator<Item = (&Id, &EffectiveVisibility)> {
-        self.map.iter()
-    }
-
-    pub fn map_id<OutId: Hash + Eq + Copy>(&self, f: impl Fn(Id) -> OutId) -> AccessLevels<OutId> {
-        AccessLevels { map: self.map.iter().map(|(k, v)| (f(*k), *v)).collect() }
-    }
-
-    pub fn set_access_level(
+    // FIXME: Share code with `fn update`.
+    pub fn update_eff_vis(
         &mut self,
-        id: Id,
+        def_id: LocalDefId,
+        eff_vis: &EffectiveVisibility,
+        tree: impl DefIdTree,
+    ) {
+        use std::collections::hash_map::Entry;
+        match self.map.entry(def_id) {
+            Entry::Occupied(mut occupied) => {
+                let old_eff_vis = occupied.get_mut();
+                for l in Level::all_levels() {
+                    let vis_at_level = eff_vis.at_level(l);
+                    let old_vis_at_level = old_eff_vis.at_level_mut(l);
+                    if vis_at_level != old_vis_at_level
+                        && vis_at_level.is_at_least(*old_vis_at_level, tree)
+                    {
+                        *old_vis_at_level = *vis_at_level
+                    }
+                }
+                old_eff_vis
+            }
+            Entry::Vacant(vacant) => vacant.insert(*eff_vis),
+        };
+    }
+
+    pub fn set_public_at_level(
+        &mut self,
+        id: LocalDefId,
         default_vis: impl FnOnce() -> Visibility,
-        tag: AccessLevel,
+        level: Level,
     ) {
         let mut effective_vis = self
-            .get_effective_vis(id)
+            .effective_vis(id)
             .copied()
             .unwrap_or_else(|| EffectiveVisibility::from_vis(default_vis()));
-        for level in AccessLevel::all_levels() {
-            if level <= tag {
-                *effective_vis.get_mut(level) = Visibility::Public;
+        for l in Level::all_levels() {
+            if l <= level {
+                *effective_vis.at_level_mut(l) = Visibility::Public;
             }
         }
         self.map.insert(id, effective_vis);
     }
+
+    pub fn check_invariants(&self, tcx: TyCtxt<'_>, early: bool) {
+        if !cfg!(debug_assertions) {
+            return;
+        }
+        for (&def_id, ev) in &self.map {
+            // More direct visibility levels can never go farther than less direct ones,
+            // neither of effective visibilities can go farther than nominal visibility,
+            // and all effective visibilities are larger or equal than private visibility.
+            let private_vis = Visibility::Restricted(tcx.parent_module_from_def_id(def_id));
+            let span = tcx.def_span(def_id.to_def_id());
+            if !ev.direct.is_at_least(private_vis, tcx) {
+                span_bug!(span, "private {:?} > direct {:?}", private_vis, ev.direct);
+            }
+            if !ev.reexported.is_at_least(ev.direct, tcx) {
+                span_bug!(span, "direct {:?} > reexported {:?}", ev.direct, ev.reexported);
+            }
+            if !ev.reachable.is_at_least(ev.reexported, tcx) {
+                span_bug!(span, "reexported {:?} > reachable {:?}", ev.reexported, ev.reachable);
+            }
+            if !ev.reachable_through_impl_trait.is_at_least(ev.reachable, tcx) {
+                span_bug!(
+                    span,
+                    "reachable {:?} > reachable_through_impl_trait {:?}",
+                    ev.reachable,
+                    ev.reachable_through_impl_trait
+                );
+            }
+            let nominal_vis = tcx.visibility(def_id);
+            let def_kind = tcx.opt_def_kind(def_id);
+            // FIXME: `rustc_privacy` is not yet updated for the new logic and can set
+            // effective visibilities that are larger than the nominal one.
+            if !nominal_vis.is_at_least(ev.reachable_through_impl_trait, tcx) && early {
+                span_bug!(
+                    span,
+                    "{:?}: reachable_through_impl_trait {:?} > nominal {:?}",
+                    def_id,
+                    ev.reachable_through_impl_trait,
+                    nominal_vis
+                );
+            }
+            // Fully private items are never put into the table, this is important for performance.
+            // FIXME: Fully private `mod` items are currently put into the table.
+            if ev.reachable_through_impl_trait == private_vis && def_kind != Some(DefKind::Mod) {
+                span_bug!(span, "fully private item in the table {:?}: {:?}", def_id, ev.direct);
+            }
+        }
+    }
 }
 
-impl<Id: Hash + Eq + Copy + Into<DefId>> AccessLevels<Id> {
+impl<Id: Eq + Hash> EffectiveVisibilities<Id> {
+    pub fn iter(&self) -> impl Iterator<Item = (&Id, &EffectiveVisibility)> {
+        self.map.iter()
+    }
+
+    pub fn effective_vis(&self, id: Id) -> Option<&EffectiveVisibility> {
+        self.map.get(&id)
+    }
+
     // `parent_id` is not necessarily a parent in source code tree,
     // it is the node from which the maximum effective visibility is inherited.
     pub fn update(
         &mut self,
         id: Id,
         nominal_vis: Visibility,
-        default_vis: impl FnOnce() -> Visibility,
-        parent_id: Id,
-        tag: AccessLevel,
+        default_vis: Visibility,
+        inherited_eff_vis: Option<EffectiveVisibility>,
+        level: Level,
         tree: impl DefIdTree,
-    ) -> Result<bool, ()> {
+    ) -> bool {
         let mut changed = false;
         let mut current_effective_vis = self
-            .get_effective_vis(id)
+            .map
+            .get(&id)
             .copied()
-            .unwrap_or_else(|| EffectiveVisibility::from_vis(default_vis()));
-        if let Some(inherited_effective_vis) = self.get_effective_vis(parent_id) {
-            for level in AccessLevel::all_levels() {
-                if tag >= level {
-                    let inherited_effective_vis_at_level = *inherited_effective_vis.get(level);
-                    let calculated_effective_vis =
-                        if nominal_vis.is_at_least(inherited_effective_vis_at_level, tree) {
-                            inherited_effective_vis_at_level
-                        } else {
-                            nominal_vis
-                        };
-                    changed |= current_effective_vis.update(calculated_effective_vis, level, tree);
+            .unwrap_or_else(|| EffectiveVisibility::from_vis(default_vis));
+        if let Some(inherited_effective_vis) = inherited_eff_vis {
+            let mut inherited_effective_vis_at_prev_level =
+                *inherited_effective_vis.at_level(level);
+            let mut calculated_effective_vis = inherited_effective_vis_at_prev_level;
+            for l in Level::all_levels() {
+                if level >= l {
+                    let inherited_effective_vis_at_level = *inherited_effective_vis.at_level(l);
+                    let current_effective_vis_at_level = current_effective_vis.at_level_mut(l);
+                    // effective visibility for id shouldn't be recalculated if
+                    // inherited from parent_id effective visibility isn't changed at next level
+                    if !(inherited_effective_vis_at_prev_level == inherited_effective_vis_at_level
+                        && level != l)
+                    {
+                        calculated_effective_vis =
+                            if nominal_vis.is_at_least(inherited_effective_vis_at_level, tree) {
+                                inherited_effective_vis_at_level
+                            } else {
+                                nominal_vis
+                            };
+                    }
+                    // effective visibility can't be decreased at next update call for the
+                    // same id
+                    if *current_effective_vis_at_level != calculated_effective_vis
+                        && calculated_effective_vis
+                            .is_at_least(*current_effective_vis_at_level, tree)
+                    {
+                        changed = true;
+                        *current_effective_vis_at_level = calculated_effective_vis;
+                    }
+                    inherited_effective_vis_at_prev_level = inherited_effective_vis_at_level;
                 }
             }
-        } else {
-            if !id.into().is_crate_root() {
-                return Err(());
-            }
-            changed |= current_effective_vis.update(Visibility::Public, AccessLevel::Public, tree);
         }
         self.map.insert(id, current_effective_vis);
-        Ok(changed)
+        changed
     }
 }
 
-impl<Id> Default for AccessLevels<Id> {
+impl<Id> Default for EffectiveVisibilities<Id> {
     fn default() -> Self {
-        AccessLevels { map: Default::default() }
+        EffectiveVisibilities { map: Default::default() }
     }
 }
 
-impl<'a> HashStable<StableHashingContext<'a>> for AccessLevels {
+impl<'a> HashStable<StableHashingContext<'a>> for EffectiveVisibilities {
     fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) {
-        let AccessLevels { ref map } = *self;
+        let EffectiveVisibilities { ref map } = *self;
         map.hash_stable(hcx, hasher);
     }
 }
diff --git a/compiler/rustc_middle/src/mir/generic_graphviz.rs b/compiler/rustc_middle/src/mir/generic_graphviz.rs
index 11ac45943ac5..ccae7e159b1f 100644
--- a/compiler/rustc_middle/src/mir/generic_graphviz.rs
+++ b/compiler/rustc_middle/src/mir/generic_graphviz.rs
@@ -126,7 +126,7 @@ impl<
             write!(
                 w,
                 r#"<tr><td align="left" balign="left">{}</td></tr>"#,
-                dot::escape_html(&section).replace('\n', "<br/>")
+                dot::escape_html(&section)
             )?;
         }
 
@@ -147,7 +147,7 @@ impl<
             let src = self.node(source);
             let trg = self.node(target);
             let escaped_edge_label = if let Some(edge_label) = edge_labels.get(index) {
-                dot::escape_html(edge_label).replace('\n', r#"<br align="left"/>"#)
+                dot::escape_html(edge_label)
             } else {
                 "".to_owned()
             };
@@ -162,8 +162,7 @@ impl<
     where
         W: Write,
     {
-        let lines = label.split('\n').map(|s| dot::escape_html(s)).collect::<Vec<_>>();
-        let escaped_label = lines.join(r#"<br align="left"/>"#);
+        let escaped_label = dot::escape_html(label);
         writeln!(w, r#"    label=<<br/><br/>{}<br align="left"/><br/><br/><br/>>;"#, escaped_label)
     }
 
diff --git a/compiler/rustc_middle/src/mir/interpret/mod.rs b/compiler/rustc_middle/src/mir/interpret/mod.rs
index 5e3dfcbcc496..32ec58557692 100644
--- a/compiler/rustc_middle/src/mir/interpret/mod.rs
+++ b/compiler/rustc_middle/src/mir/interpret/mod.rs
@@ -106,6 +106,7 @@ use rustc_ast::LitKind;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sync::{HashMapExt, Lock};
 use rustc_data_structures::tiny_list::TinyList;
+use rustc_errors::ErrorGuaranteed;
 use rustc_hir::def_id::DefId;
 use rustc_macros::HashStable;
 use rustc_middle::ty::print::with_no_trimmed_paths;
@@ -176,7 +177,7 @@ pub enum LitToConstError {
     /// This is used for graceful error handling (`delay_span_bug`) in
     /// type checking (`Const::from_anon_const`).
     TypeError,
-    Reported,
+    Reported(ErrorGuaranteed),
 }
 
 #[derive(Copy, Clone, Eq, Hash, Ord, PartialEq, PartialOrd)]
diff --git a/compiler/rustc_middle/src/mir/mod.rs b/compiler/rustc_middle/src/mir/mod.rs
index e0e823e2090e..4781651071d3 100644
--- a/compiler/rustc_middle/src/mir/mod.rs
+++ b/compiler/rustc_middle/src/mir/mod.rs
@@ -116,11 +116,6 @@ pub trait MirPass<'tcx> {
 
     fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>);
 
-    /// If this pass causes the MIR to enter a new phase, return that phase.
-    fn phase_change(&self) -> Option<MirPhase> {
-        None
-    }
-
     fn is_mir_dump_enabled(&self) -> bool {
         true
     }
@@ -143,6 +138,77 @@ impl MirPhase {
             }
         }
     }
+
+    /// Parses an `MirPhase` from a pair of strings. Panics if this isn't possible for any reason.
+    pub fn parse(dialect: String, phase: Option<String>) -> Self {
+        match &*dialect.to_ascii_lowercase() {
+            "built" => {
+                assert!(phase.is_none(), "Cannot specify a phase for `Built` MIR");
+                MirPhase::Built
+            }
+            "analysis" => Self::Analysis(AnalysisPhase::parse(phase)),
+            "runtime" => Self::Runtime(RuntimePhase::parse(phase)),
+            _ => panic!("Unknown MIR dialect {}", dialect),
+        }
+    }
+}
+
+impl AnalysisPhase {
+    pub fn parse(phase: Option<String>) -> Self {
+        let Some(phase) = phase else {
+            return Self::Initial;
+        };
+
+        match &*phase.to_ascii_lowercase() {
+            "initial" => Self::Initial,
+            "post_cleanup" | "post-cleanup" | "postcleanup" => Self::PostCleanup,
+            _ => panic!("Unknown analysis phase {}", phase),
+        }
+    }
+}
+
+impl RuntimePhase {
+    pub fn parse(phase: Option<String>) -> Self {
+        let Some(phase) = phase else {
+            return Self::Initial;
+        };
+
+        match &*phase.to_ascii_lowercase() {
+            "initial" => Self::Initial,
+            "post_cleanup" | "post-cleanup" | "postcleanup" => Self::PostCleanup,
+            "optimized" => Self::Optimized,
+            _ => panic!("Unknown runtime phase {}", phase),
+        }
+    }
+}
+
+impl Display for MirPhase {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        match self {
+            MirPhase::Built => write!(f, "built"),
+            MirPhase::Analysis(p) => write!(f, "analysis-{}", p),
+            MirPhase::Runtime(p) => write!(f, "runtime-{}", p),
+        }
+    }
+}
+
+impl Display for AnalysisPhase {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        match self {
+            AnalysisPhase::Initial => write!(f, "initial"),
+            AnalysisPhase::PostCleanup => write!(f, "post_cleanup"),
+        }
+    }
+}
+
+impl Display for RuntimePhase {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        match self {
+            RuntimePhase::Initial => write!(f, "initial"),
+            RuntimePhase::PostCleanup => write!(f, "post_cleanup"),
+            RuntimePhase::Optimized => write!(f, "optimized"),
+        }
+    }
 }
 
 /// Where a specific `mir::Body` comes from.
@@ -207,6 +273,9 @@ pub struct Body<'tcx> {
     /// us to see the difference and forego optimization on the inlined promoted items.
     pub phase: MirPhase,
 
+    /// How many passses we have executed since starting the current phase. Used for debug output.
+    pub pass_count: usize,
+
     pub source: MirSource<'tcx>,
 
     /// A list of source scopes; these are referenced by statements
@@ -266,6 +335,13 @@ pub struct Body<'tcx> {
     /// potentially allow things like `[u8; std::mem::size_of::<T>() * 0]` due to this.
     pub is_polymorphic: bool,
 
+    /// The phase at which this MIR should be "injected" into the compilation process.
+    ///
+    /// Everything that comes before this `MirPhase` should be skipped.
+    ///
+    /// This is only `Some` if the function that this body comes from was annotated with `rustc_custom_mir`.
+    pub injection_phase: Option<MirPhase>,
+
     pub tainted_by_errors: Option<ErrorGuaranteed>,
 }
 
@@ -292,6 +368,7 @@ impl<'tcx> Body<'tcx> {
 
         let mut body = Body {
             phase: MirPhase::Built,
+            pass_count: 1,
             source,
             basic_blocks: BasicBlocks::new(basic_blocks),
             source_scopes,
@@ -311,6 +388,7 @@ impl<'tcx> Body<'tcx> {
             span,
             required_consts: Vec::new(),
             is_polymorphic: false,
+            injection_phase: None,
             tainted_by_errors,
         };
         body.is_polymorphic = body.has_non_region_param();
@@ -325,6 +403,7 @@ impl<'tcx> Body<'tcx> {
     pub fn new_cfg_only(basic_blocks: IndexVec<BasicBlock, BasicBlockData<'tcx>>) -> Self {
         let mut body = Body {
             phase: MirPhase::Built,
+            pass_count: 1,
             source: MirSource::item(CRATE_DEF_ID.to_def_id()),
             basic_blocks: BasicBlocks::new(basic_blocks),
             source_scopes: IndexVec::new(),
@@ -337,6 +416,7 @@ impl<'tcx> Body<'tcx> {
             required_consts: Vec::new(),
             var_debug_info: Vec::new(),
             is_polymorphic: false,
+            injection_phase: None,
             tainted_by_errors: None,
         };
         body.is_polymorphic = body.has_non_region_param();
@@ -479,6 +559,14 @@ impl<'tcx> Body<'tcx> {
     pub fn generator_kind(&self) -> Option<GeneratorKind> {
         self.generator.as_ref().map(|generator| generator.generator_kind)
     }
+
+    #[inline]
+    pub fn should_skip(&self) -> bool {
+        let Some(injection_phase) = self.injection_phase else {
+            return false;
+        };
+        injection_phase > self.phase
+    }
 }
 
 #[derive(Copy, Clone, PartialEq, Eq, Debug, TyEncodable, TyDecodable, HashStable)]
@@ -1157,6 +1245,11 @@ impl<'tcx> BasicBlockData<'tcx> {
     pub fn visitable(&self, index: usize) -> &dyn MirVisitable<'tcx> {
         if index < self.statements.len() { &self.statements[index] } else { &self.terminator }
     }
+
+    /// Does the block have no statements and an unreachable terminator?
+    pub fn is_empty_unreachable(&self) -> bool {
+        self.statements.is_empty() && matches!(self.terminator().kind, TerminatorKind::Unreachable)
+    }
 }
 
 impl<O> AssertKind<O> {
@@ -1448,7 +1541,7 @@ impl<'tcx> Place<'tcx> {
     /// If MirPhase >= Derefered and if projection contains Deref,
     /// It's guaranteed to be in the first place
     pub fn has_deref(&self) -> bool {
-        // To make sure this is not accidently used in wrong mir phase
+        // To make sure this is not accidentally used in wrong mir phase
         debug_assert!(
             self.projection.is_empty() || !self.projection[1..].contains(&PlaceElem::Deref)
         );
@@ -1864,6 +1957,7 @@ impl BorrowKind {
         }
     }
 
+    // FIXME: won't be used after diagnostic migration
     pub fn describe_mutability(&self) -> &str {
         match *self {
             BorrowKind::Shared | BorrowKind::Shallow | BorrowKind::Unique => "immutable",
@@ -2158,7 +2252,9 @@ impl<'tcx> ConstantKind<'tcx> {
                 match tcx.const_eval_resolve(param_env, uneval, None) {
                     Ok(val) => Self::Val(val, ty),
                     Err(ErrorHandled::TooGeneric | ErrorHandled::Linted) => self,
-                    Err(_) => Self::Ty(tcx.const_error(ty)),
+                    Err(ErrorHandled::Reported(guar)) => {
+                        Self::Ty(tcx.const_error_with_guaranteed(ty, guar))
+                    }
                 }
             }
         }
@@ -2380,10 +2476,8 @@ impl<'tcx> ConstantKind<'tcx> {
                 let generics = tcx.generics_of(item_def_id.to_def_id());
                 let index = generics.param_def_id_to_index[&def_id];
                 let name = tcx.hir().name(hir_id);
-                let ty_const = tcx.mk_const(ty::ConstS {
-                    kind: ty::ConstKind::Param(ty::ParamConst::new(index, name)),
-                    ty,
-                });
+                let ty_const =
+                    tcx.mk_const(ty::ConstKind::Param(ty::ParamConst::new(index, name)), ty);
                 debug!(?ty_const);
 
                 return Self::Ty(ty_const);
@@ -2875,7 +2969,7 @@ fn pretty_print_const_value<'tcx>(
 /// `Location` represents the position of the start of the statement; or, if
 /// `statement_index` equals the number of statements, then the start of the
 /// terminator.
-#[derive(Copy, Clone, PartialEq, Eq, Hash, Ord, PartialOrd, HashStable, TyEncodable, TyDecodable)]
+#[derive(Copy, Clone, PartialEq, Eq, Hash, Ord, PartialOrd, HashStable)]
 pub struct Location {
     /// The block that the location is within.
     pub block: BasicBlock,
diff --git a/compiler/rustc_middle/src/mir/mono.rs b/compiler/rustc_middle/src/mir/mono.rs
index fdda62719ee1..15a24aa4ace5 100644
--- a/compiler/rustc_middle/src/mir/mono.rs
+++ b/compiler/rustc_middle/src/mir/mono.rs
@@ -81,7 +81,7 @@ impl<'tcx> MonoItem<'tcx> {
             MonoItem::Fn(instance) => tcx.symbol_name(instance),
             MonoItem::Static(def_id) => tcx.symbol_name(Instance::mono(tcx, def_id)),
             MonoItem::GlobalAsm(item_id) => {
-                SymbolName::new(tcx, &format!("global_asm_{:?}", item_id.def_id))
+                SymbolName::new(tcx, &format!("global_asm_{:?}", item_id.owner_id))
             }
         }
     }
@@ -182,7 +182,7 @@ impl<'tcx> MonoItem<'tcx> {
         match *self {
             MonoItem::Fn(Instance { def, .. }) => def.def_id().as_local(),
             MonoItem::Static(def_id) => def_id.as_local(),
-            MonoItem::GlobalAsm(item_id) => Some(item_id.def_id.def_id),
+            MonoItem::GlobalAsm(item_id) => Some(item_id.owner_id.def_id),
         }
         .map(|def_id| tcx.def_span(def_id))
     }
@@ -373,7 +373,7 @@ impl<'tcx> CodegenUnit<'tcx> {
                         }
                     }
                     MonoItem::Static(def_id) => def_id.as_local().map(Idx::index),
-                    MonoItem::GlobalAsm(item_id) => Some(item_id.def_id.def_id.index()),
+                    MonoItem::GlobalAsm(item_id) => Some(item_id.owner_id.def_id.index()),
                 },
                 item.symbol_name(tcx),
             )
diff --git a/compiler/rustc_middle/src/mir/query.rs b/compiler/rustc_middle/src/mir/query.rs
index 1d847d8f3d31..efd7357afc46 100644
--- a/compiler/rustc_middle/src/mir/query.rs
+++ b/compiler/rustc_middle/src/mir/query.rs
@@ -15,7 +15,7 @@ use smallvec::SmallVec;
 use std::cell::Cell;
 use std::fmt::{self, Debug};
 
-use super::{Field, Location, SourceInfo};
+use super::{Field, SourceInfo};
 
 #[derive(Copy, Clone, PartialEq, TyEncodable, TyDecodable, HashStable, Debug)]
 pub enum UnsafetyViolationKind {
@@ -314,12 +314,12 @@ pub struct ClosureOutlivesRequirement<'tcx> {
     pub blame_span: Span,
 
     // ... due to this reason.
-    pub category: ConstraintCategory,
+    pub category: ConstraintCategory<'tcx>,
 }
 
 // Make sure this enum doesn't unintentionally grow
 #[cfg(all(target_arch = "x86_64", target_pointer_width = "64"))]
-rustc_data_structures::static_assert_size!(ConstraintCategory, 16);
+rustc_data_structures::static_assert_size!(ConstraintCategory<'_>, 16);
 
 /// Outlives-constraints can be categorized to determine whether and why they
 /// are interesting (for error reporting). Order of variants indicates sort
@@ -327,8 +327,8 @@ rustc_data_structures::static_assert_size!(ConstraintCategory, 16);
 ///
 /// See also `rustc_const_eval::borrow_check::constraints`.
 #[derive(Copy, Clone, Debug, Eq, PartialEq, PartialOrd, Ord, Hash)]
-#[derive(TyEncodable, TyDecodable, HashStable)]
-pub enum ConstraintCategory {
+#[derive(TyEncodable, TyDecodable, HashStable, Lift, TypeVisitable, TypeFoldable)]
+pub enum ConstraintCategory<'tcx> {
     Return(ReturnConstraint),
     Yield,
     UseAsConst,
@@ -342,7 +342,7 @@ pub enum ConstraintCategory {
     ClosureBounds,
 
     /// Contains the function type if available.
-    CallArgument(Location),
+    CallArgument(Option<Ty<'tcx>>),
     CopyBound,
     SizedBound,
     Assignment,
@@ -368,10 +368,6 @@ pub enum ConstraintCategory {
     Internal,
 }
 
-TrivialTypeTraversalAndLiftImpls! {
-    ConstraintCategory,
-}
-
 #[derive(Copy, Clone, Debug, Eq, PartialEq, PartialOrd, Ord, Hash)]
 #[derive(TyEncodable, TyDecodable, HashStable, TypeVisitable, TypeFoldable)]
 pub enum ReturnConstraint {
diff --git a/compiler/rustc_middle/src/mir/syntax.rs b/compiler/rustc_middle/src/mir/syntax.rs
index 85ef51f129bb..fed943169dfb 100644
--- a/compiler/rustc_middle/src/mir/syntax.rs
+++ b/compiler/rustc_middle/src/mir/syntax.rs
@@ -85,7 +85,7 @@ pub enum MirPhase {
     ///
     /// Also note that the lint pass which reports eg `200_u8 + 200_u8` as an error is run as a part
     /// of analysis to runtime MIR lowering. To ensure lints are reported reliably, this means that
-    /// transformations which may supress such errors should not run on analysis MIR.
+    /// transformations which may suppress such errors should not run on analysis MIR.
     Runtime(RuntimePhase),
 }
 
diff --git a/compiler/rustc_middle/src/mir/visit.rs b/compiler/rustc_middle/src/mir/visit.rs
index ddcf3711bfc9..d87eb28970e4 100644
--- a/compiler/rustc_middle/src/mir/visit.rs
+++ b/compiler/rustc_middle/src/mir/visit.rs
@@ -1320,6 +1320,15 @@ impl PlaceContext {
         )
     }
 
+    /// Returns `true` if this place context represents an address-of.
+    pub fn is_address_of(&self) -> bool {
+        matches!(
+            self,
+            PlaceContext::NonMutatingUse(NonMutatingUseContext::AddressOf)
+                | PlaceContext::MutatingUse(MutatingUseContext::AddressOf)
+        )
+    }
+
     /// Returns `true` if this place context represents a storage live or storage dead marker.
     #[inline]
     pub fn is_storage_marker(&self) -> bool {
diff --git a/compiler/rustc_middle/src/query/mod.rs b/compiler/rustc_middle/src/query/mod.rs
index 2ab3b0d27c88..1564cf414bd2 100644
--- a/compiler/rustc_middle/src/query/mod.rs
+++ b/compiler/rustc_middle/src/query/mod.rs
@@ -23,7 +23,7 @@ rustc_queries! {
         desc { "triggering a delay span bug" }
     }
 
-    query resolutions(_: ()) -> &'tcx ty::ResolverOutputs {
+    query resolutions(_: ()) -> &'tcx ty::ResolverGlobalCtxt {
         eval_always
         no_hash
         desc { "getting the resolver outputs" }
@@ -271,6 +271,10 @@ rustc_queries! {
         desc { |tcx| "elaborating item bounds for `{}`", tcx.def_path_str(key) }
     }
 
+    /// Look up all native libraries this crate depends on.
+    /// These are assembled from the following places:
+    /// - `extern` blocks (depending on their `link` attributes)
+    /// - the `libs` (`-l`) option
     query native_libraries(_: CrateNum) -> Vec<NativeLib> {
         arena_cache
         desc { "looking up the native libraries of a linked crate" }
@@ -912,7 +916,7 @@ rustc_queries! {
         cache_on_disk_if { true }
     }
 
-    query used_trait_imports(key: LocalDefId) -> &'tcx FxHashSet<LocalDefId> {
+    query used_trait_imports(key: LocalDefId) -> &'tcx UnordSet<LocalDefId> {
         desc { |tcx| "finding used_trait_imports `{}`", tcx.def_path_str(key.to_def_id()) }
         cache_on_disk_if { true }
     }
@@ -1065,10 +1069,10 @@ rustc_queries! {
         cache_on_disk_if { key.is_local() }
     }
 
-    /// Performs part of the privacy check and computes "access levels".
-    query privacy_access_levels(_: ()) -> &'tcx AccessLevels {
+    /// Performs part of the privacy check and computes effective visibilities.
+    query effective_visibilities(_: ()) -> &'tcx EffectiveVisibilities {
         eval_always
-        desc { "checking privacy access levels" }
+        desc { "checking effective visibilities" }
     }
     query check_private_in_public(_: ()) -> () {
         eval_always
@@ -1391,6 +1395,13 @@ rustc_queries! {
         desc { "checking if the crate has_global_allocator" }
         separate_provide_extern
     }
+    query has_alloc_error_handler(_: CrateNum) -> bool {
+        // This query depends on untracked global state in CStore
+        eval_always
+        fatal_cycle
+        desc { "checking if the crate has_alloc_error_handler" }
+        separate_provide_extern
+    }
     query has_panic_handler(_: CrateNum) -> bool {
         fatal_cycle
         desc { "checking if the crate has_panic_handler" }
@@ -1532,6 +1543,7 @@ rustc_queries! {
         desc { "available upstream drop-glue for `{:?}`", substs }
     }
 
+    /// Returns a list of all `extern` blocks of a crate.
     query foreign_modules(_: CrateNum) -> FxHashMap<DefId, ForeignModule> {
         arena_cache
         desc { "looking up the foreign modules of a linked crate" }
@@ -1543,9 +1555,12 @@ rustc_queries! {
     query entry_fn(_: ()) -> Option<(DefId, EntryFnType)> {
         desc { "looking up the entry function of a crate" }
     }
+
+    /// Finds the `rustc_proc_macro_decls` item of a crate.
     query proc_macro_decls_static(_: ()) -> Option<LocalDefId> {
-        desc { "looking up the derive registrar for a crate" }
+        desc { "looking up the proc macro declarations for a crate" }
     }
+
     // The macro which defines `rustc_metadata::provide_extern` depends on this query's name.
     // Changing the name should cause a compiler error, but in case that changes, be aware.
     query crate_hash(_: CrateNum) -> Svh {
@@ -1553,17 +1568,24 @@ rustc_queries! {
         desc { "looking up the hash a crate" }
         separate_provide_extern
     }
+
+    /// Gets the hash for the host proc macro. Used to support -Z dual-proc-macro.
     query crate_host_hash(_: CrateNum) -> Option<Svh> {
         eval_always
         desc { "looking up the hash of a host version of a crate" }
         separate_provide_extern
     }
+
+    /// Gets the extra data to put in each output filename for a crate.
+    /// For example, compiling the `foo` crate with `extra-filename=-a` creates a `libfoo-b.rlib` file.
     query extra_filename(_: CrateNum) -> String {
         arena_cache
         eval_always
         desc { "looking up the extra filename for a crate" }
         separate_provide_extern
     }
+
+    /// Gets the paths where the crate came from in the file system.
     query crate_extern_paths(_: CrateNum) -> Vec<PathBuf> {
         arena_cache
         eval_always
@@ -1587,23 +1609,15 @@ rustc_queries! {
         separate_provide_extern
     }
 
+    /// Get the corresponding native library from the `native_libraries` query
     query native_library(def_id: DefId) -> Option<&'tcx NativeLib> {
         desc { |tcx| "getting the native library for `{}`", tcx.def_path_str(def_id) }
     }
 
-    /// Does lifetime resolution, but does not descend into trait items. This
-    /// should only be used for resolving lifetimes of on trait definitions,
-    /// and is used to avoid cycles. Importantly, `resolve_lifetimes` still visits
-    /// the same lifetimes and is responsible for diagnostics.
-    /// See `rustc_resolve::late::lifetimes for details.
-    query resolve_lifetimes_trait_definition(_: LocalDefId) -> ResolveLifetimes {
-        arena_cache
-        desc { "resolving lifetimes for a trait definition" }
-    }
     /// Does lifetime resolution on items. Importantly, we can't resolve
     /// lifetimes directly on things like trait methods, because of trait params.
     /// See `rustc_resolve::late::lifetimes for details.
-    query resolve_lifetimes(_: LocalDefId) -> ResolveLifetimes {
+    query resolve_lifetimes(_: hir::OwnerId) -> ResolveLifetimes {
         arena_cache
         desc { "resolving lifetimes" }
     }
@@ -1705,7 +1719,7 @@ rustc_queries! {
     }
 
     /// Returns the lang items defined in another crate by loading it from metadata.
-    query defined_lang_items(_: CrateNum) -> &'tcx [(DefId, usize)] {
+    query defined_lang_items(_: CrateNum) -> &'tcx [(DefId, LangItem)] {
         desc { "calculating the lang items defined in a crate" }
         separate_provide_extern
     }
@@ -1761,6 +1775,10 @@ rustc_queries! {
         eval_always
         desc { "getting the allocator kind for the current crate" }
     }
+    query alloc_error_handler_kind(_: ()) -> Option<AllocatorKind> {
+        eval_always
+        desc { "alloc error handler kind for the current crate" }
+    }
 
     query upvars_mentioned(def_id: DefId) -> Option<&'tcx FxIndexMap<hir::HirId, hir::Upvar>> {
         desc { |tcx| "collecting upvars mentioned in `{}`", tcx.def_path_str(def_id) }
diff --git a/compiler/rustc_middle/src/traits/mod.rs b/compiler/rustc_middle/src/traits/mod.rs
index 3adc2e1b73e4..05382bd887cd 100644
--- a/compiler/rustc_middle/src/traits/mod.rs
+++ b/compiler/rustc_middle/src/traits/mod.rs
@@ -185,7 +185,7 @@ impl<'tcx> ObligationCause<'tcx> {
         self
     }
 
-    pub fn to_constraint_category(&self) -> ConstraintCategory {
+    pub fn to_constraint_category(&self) -> ConstraintCategory<'tcx> {
         match self.code() {
             MatchImpl(cause, _) => cause.to_constraint_category(),
             AscribeUserTypeProvePredicate(predicate_span) => {
@@ -203,13 +203,20 @@ pub struct UnifyReceiverContext<'tcx> {
     pub substs: SubstsRef<'tcx>,
 }
 
-#[derive(Clone, Debug, PartialEq, Eq, Hash, Lift, Default)]
+#[derive(Clone, PartialEq, Eq, Hash, Lift, Default)]
 pub struct InternedObligationCauseCode<'tcx> {
     /// `None` for `ObligationCauseCode::MiscObligation` (a common case, occurs ~60% of
     /// the time). `Some` otherwise.
     code: Option<Lrc<ObligationCauseCode<'tcx>>>,
 }
 
+impl<'tcx> std::fmt::Debug for InternedObligationCauseCode<'tcx> {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let cause: &ObligationCauseCode<'_> = self;
+        cause.fmt(f)
+    }
+}
+
 impl<'tcx> ObligationCauseCode<'tcx> {
     #[inline(always)]
     fn into(self) -> InternedObligationCauseCode<'tcx> {
@@ -431,6 +438,8 @@ pub enum ObligationCauseCode<'tcx> {
     },
 
     AscribeUserTypeProvePredicate(Span),
+
+    RustCall,
 }
 
 /// The 'location' at which we try to perform HIR-based wf checking.
@@ -567,9 +576,6 @@ pub enum SelectionError<'tcx> {
     /// Signaling that an error has already been emitted, to avoid
     /// multiple errors being shown.
     ErrorReporting,
-    /// Multiple applicable `impl`s where found. The `DefId`s correspond to
-    /// all the `impl`s' Items.
-    Ambiguous(Vec<DefId>),
 }
 
 /// When performing resolution, it is typically the case that there
diff --git a/compiler/rustc_middle/src/traits/specialization_graph.rs b/compiler/rustc_middle/src/traits/specialization_graph.rs
index 0a2819feecf0..cccedc9ec6ea 100644
--- a/compiler/rustc_middle/src/traits/specialization_graph.rs
+++ b/compiler/rustc_middle/src/traits/specialization_graph.rs
@@ -1,3 +1,4 @@
+use crate::error::StrictCoherenceNeedsNegativeCoherence;
 use crate::ty::fast_reject::SimplifiedType;
 use crate::ty::visit::TypeVisitable;
 use crate::ty::{self, TyCtxt};
@@ -65,9 +66,21 @@ impl OverlapMode {
 
         if with_negative_coherence {
             if strict_coherence { OverlapMode::Strict } else { OverlapMode::WithNegative }
-        } else if strict_coherence {
-            bug!("To use strict_coherence you need to set with_negative_coherence feature flag");
         } else {
+            if strict_coherence {
+                let attr_span = trait_id
+                    .as_local()
+                    .into_iter()
+                    .flat_map(|local_def_id| {
+                        tcx.hir().attrs(tcx.hir().local_def_id_to_hir_id(local_def_id))
+                    })
+                    .find(|attr| attr.has_name(sym::rustc_strict_coherence))
+                    .map(|attr| attr.span);
+                tcx.sess.emit_err(StrictCoherenceNeedsNegativeCoherence {
+                    span: tcx.def_span(trait_id),
+                    attr_span,
+                });
+            }
             OverlapMode::Stable
         }
     }
@@ -249,7 +262,7 @@ pub fn ancestors<'tcx>(
 
     if let Some(reported) = specialization_graph.has_errored {
         Err(reported)
-    } else if let Some(reported) = tcx.type_of(start_from_impl).error_reported() {
+    } else if let Err(reported) = tcx.type_of(start_from_impl).error_reported() {
         Err(reported)
     } else {
         Ok(Ancestors {
diff --git a/compiler/rustc_middle/src/ty/abstract_const.rs b/compiler/rustc_middle/src/ty/abstract_const.rs
index 1aa4df778008..e5bcd5fb27aa 100644
--- a/compiler/rustc_middle/src/ty/abstract_const.rs
+++ b/compiler/rustc_middle/src/ty/abstract_const.rs
@@ -1,7 +1,7 @@
 //! A subset of a mir body used for const evaluatability checking.
 use crate::mir;
 use crate::ty::visit::TypeVisitable;
-use crate::ty::{self, DelaySpanBugEmitted, EarlyBinder, SubstsRef, Ty, TyCtxt};
+use crate::ty::{self, EarlyBinder, SubstsRef, Ty, TyCtxt};
 use rustc_errors::ErrorGuaranteed;
 use rustc_hir::def_id::DefId;
 use std::cmp;
@@ -43,7 +43,7 @@ impl<'tcx> AbstractConst<'tcx> {
     ) -> Result<Option<AbstractConst<'tcx>>, ErrorGuaranteed> {
         match ct.kind() {
             ty::ConstKind::Unevaluated(uv) => AbstractConst::new(tcx, uv),
-            ty::ConstKind::Error(DelaySpanBugEmitted { reported, .. }) => Err(reported),
+            ty::ConstKind::Error(reported) => Err(reported),
             _ => Ok(None),
         }
     }
diff --git a/compiler/rustc_middle/src/ty/codec.rs b/compiler/rustc_middle/src/ty/codec.rs
index 14ec88b7e0d7..7263e8306cf0 100644
--- a/compiler/rustc_middle/src/ty/codec.rs
+++ b/compiler/rustc_middle/src/ty/codec.rs
@@ -310,7 +310,8 @@ impl<'tcx, D: TyDecoder<I = TyCtxt<'tcx>>> RefDecodable<'tcx, D>
 
 impl<'tcx, D: TyDecoder<I = TyCtxt<'tcx>>> Decodable<D> for ty::Const<'tcx> {
     fn decode(decoder: &mut D) -> Self {
-        decoder.interner().mk_const(Decodable::decode(decoder))
+        let consts: ty::ConstS<'tcx> = Decodable::decode(decoder);
+        decoder.interner().mk_const(consts.kind, consts.ty)
     }
 }
 
diff --git a/compiler/rustc_middle/src/ty/consts.rs b/compiler/rustc_middle/src/ty/consts.rs
index f998e6083448..e2e2761501b4 100644
--- a/compiler/rustc_middle/src/ty/consts.rs
+++ b/compiler/rustc_middle/src/ty/consts.rs
@@ -2,7 +2,6 @@ use crate::mir::interpret::LitToConstInput;
 use crate::mir::ConstantKind;
 use crate::ty::{self, InternalSubsts, ParamEnv, ParamEnvAnd, Ty, TyCtxt};
 use rustc_data_structures::intern::Interned;
-use rustc_errors::ErrorGuaranteed;
 use rustc_hir as hir;
 use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_macros::HashStable;
@@ -77,13 +76,13 @@ impl<'tcx> Const<'tcx> {
 
         match Self::try_eval_lit_or_param(tcx, ty, expr) {
             Some(v) => v,
-            None => tcx.mk_const(ty::ConstS {
-                kind: ty::ConstKind::Unevaluated(ty::UnevaluatedConst {
+            None => tcx.mk_const(
+                ty::ConstKind::Unevaluated(ty::UnevaluatedConst {
                     def: def.to_global(),
                     substs: InternalSubsts::identity_for_item(tcx, def.did.to_def_id()),
                 }),
                 ty,
-            }),
+            ),
         }
     }
 
@@ -138,10 +137,7 @@ impl<'tcx> Const<'tcx> {
                 let generics = tcx.generics_of(item_def_id.to_def_id());
                 let index = generics.param_def_id_to_index[&def_id];
                 let name = tcx.hir().name(hir_id);
-                Some(tcx.mk_const(ty::ConstS {
-                    kind: ty::ConstKind::Param(ty::ParamConst::new(index, name)),
-                    ty,
-                }))
+                Some(tcx.mk_const(ty::ConstKind::Param(ty::ParamConst::new(index, name)), ty))
             }
             _ => None,
         }
@@ -150,7 +146,7 @@ impl<'tcx> Const<'tcx> {
     /// Interns the given value as a constant.
     #[inline]
     pub fn from_value(tcx: TyCtxt<'tcx>, val: ty::ValTree<'tcx>, ty: Ty<'tcx>) -> Self {
-        tcx.mk_const(ConstS { kind: ConstKind::Value(val), ty })
+        tcx.mk_const(ConstKind::Value(val), ty)
     }
 
     /// Panics if self.kind != ty::ConstKind::Value
@@ -228,7 +224,7 @@ impl<'tcx> Const<'tcx> {
         if let Some(val) = self.kind().try_eval_for_typeck(tcx, param_env) {
             match val {
                 Ok(val) => Const::from_value(tcx, val, self.ty()),
-                Err(ErrorGuaranteed { .. }) => tcx.const_error(self.ty()),
+                Err(guar) => tcx.const_error_with_guaranteed(self.ty(), guar),
             }
         } else {
             // Either the constant isn't evaluatable or ValTree creation failed.
@@ -243,7 +239,7 @@ impl<'tcx> Const<'tcx> {
         if let Some(val) = self.kind().try_eval_for_mir(tcx, param_env) {
             match val {
                 Ok(const_val) => ConstantKind::from_value(const_val, self.ty()),
-                Err(ErrorGuaranteed { .. }) => ConstantKind::Ty(tcx.const_error(self.ty())),
+                Err(guar) => ConstantKind::Ty(tcx.const_error_with_guaranteed(self.ty(), guar)),
             }
         } else {
             ConstantKind::Ty(self)
diff --git a/compiler/rustc_middle/src/ty/consts/kind.rs b/compiler/rustc_middle/src/ty/consts/kind.rs
index 4ab761e0715c..c1c613f6c602 100644
--- a/compiler/rustc_middle/src/ty/consts/kind.rs
+++ b/compiler/rustc_middle/src/ty/consts/kind.rs
@@ -69,7 +69,7 @@ pub enum ConstKind<'tcx> {
 
     /// A placeholder for a const which could not be computed; this is
     /// propagated to avoid useless error messages.
-    Error(ty::DelaySpanBugEmitted),
+    Error(ErrorGuaranteed),
 }
 
 #[cfg(all(target_arch = "x86_64", target_pointer_width = "64"))]
diff --git a/compiler/rustc_middle/src/ty/context.rs b/compiler/rustc_middle/src/ty/context.rs
index 0816a5cb8f16..8f96f5a9eb3e 100644
--- a/compiler/rustc_middle/src/ty/context.rs
+++ b/compiler/rustc_middle/src/ty/context.rs
@@ -34,6 +34,7 @@ use rustc_data_structures::sharded::{IntoPointer, ShardedHashMap};
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_data_structures::steal::Steal;
 use rustc_data_structures::sync::{self, Lock, Lrc, ReadGuard, RwLock, WorkerLocal};
+use rustc_data_structures::unord::UnordSet;
 use rustc_data_structures::vec_map::VecMap;
 use rustc_errors::{
     DecorateLint, DiagnosticBuilder, DiagnosticMessage, ErrorGuaranteed, MultiSpan,
@@ -79,7 +80,7 @@ use std::mem;
 use std::ops::{Bound, Deref};
 use std::sync::Arc;
 
-use super::{ImplPolarity, RvalueScopes};
+use super::{ImplPolarity, ResolverOutputs, RvalueScopes};
 
 pub trait OnDiskCache<'tcx>: rustc_data_structures::sync::Sync {
     /// Creates a new `OnDiskCache` instance from the serialized data in `data`.
@@ -116,7 +117,7 @@ impl<'tcx> Interner for TyCtxt<'tcx> {
     type BoundTy = ty::BoundTy;
     type PlaceholderType = ty::PlaceholderType;
     type InferTy = InferTy;
-    type DelaySpanBugEmitted = DelaySpanBugEmitted;
+    type ErrorGuaranteed = ErrorGuaranteed;
     type PredicateKind = ty::PredicateKind<'tcx>;
     type AllocId = crate::mir::interpret::AllocId;
 
@@ -127,15 +128,6 @@ impl<'tcx> Interner for TyCtxt<'tcx> {
     type PlaceholderRegion = ty::PlaceholderRegion;
 }
 
-/// A type that is not publicly constructable. This prevents people from making [`TyKind::Error`]s
-/// except through the error-reporting functions on a [`tcx`][TyCtxt].
-#[derive(Copy, Clone, Debug, Eq, Hash, PartialEq, PartialOrd, Ord)]
-#[derive(TyEncodable, TyDecodable, HashStable)]
-pub struct DelaySpanBugEmitted {
-    pub reported: ErrorGuaranteed,
-    _priv: (),
-}
-
 type InternedSet<'tcx, T> = ShardedHashMap<InternedInSet<'tcx, T>, ()>;
 
 pub struct CtxtInterners<'tcx> {
@@ -206,12 +198,8 @@ impl<'tcx> CtxtInterners<'tcx> {
                         Fingerprint::ZERO
                     } else {
                         let mut hasher = StableHasher::new();
-                        let mut hcx = StableHashingContext::ignore_spans(
-                            sess,
-                            definitions,
-                            cstore,
-                            source_span,
-                        );
+                        let mut hcx =
+                            StableHashingContext::new(sess, definitions, cstore, source_span);
                         kind.hash_stable(&mut hcx, &mut hasher);
                         hasher.finish()
                     };
@@ -531,7 +519,7 @@ pub struct TypeckResults<'tcx> {
     /// This is used for warning unused imports. During type
     /// checking, this `Lrc` should not be cloned: it must have a ref-count
     /// of 1 so that we can insert things into the set mutably.
-    pub used_trait_imports: Lrc<FxHashSet<LocalDefId>>,
+    pub used_trait_imports: Lrc<UnordSet<LocalDefId>>,
 
     /// If any errors occurred while type-checking this body,
     /// this field will be set to `Some(ErrorGuaranteed)`.
@@ -1067,10 +1055,9 @@ pub struct GlobalCtxt<'tcx> {
     pub consts: CommonConsts<'tcx>,
 
     definitions: RwLock<Definitions>,
-    cstore: Box<CrateStoreDyn>,
 
     /// Output of the resolver.
-    pub(crate) untracked_resolutions: ty::ResolverOutputs,
+    pub(crate) untracked_resolutions: ty::ResolverGlobalCtxt,
     untracked_resolver_for_lowering: Steal<ty::ResolverAstLowering>,
     /// The entire crate as AST. This field serves as the input for the hir_crate query,
     /// which lowers it from AST to HIR. It must not be read or used by anything else.
@@ -1233,10 +1220,7 @@ impl<'tcx> TyCtxt<'tcx> {
         lint_store: Lrc<dyn Any + sync::Send + sync::Sync>,
         arena: &'tcx WorkerLocal<Arena<'tcx>>,
         hir_arena: &'tcx WorkerLocal<hir::Arena<'tcx>>,
-        definitions: Definitions,
-        cstore: Box<CrateStoreDyn>,
-        untracked_resolutions: ty::ResolverOutputs,
-        untracked_resolver_for_lowering: ty::ResolverAstLowering,
+        resolver_outputs: ResolverOutputs,
         krate: Lrc<ast::Crate>,
         dep_graph: DepGraph,
         on_disk_cache: Option<&'tcx dyn OnDiskCache<'tcx>>,
@@ -1245,6 +1229,11 @@ impl<'tcx> TyCtxt<'tcx> {
         crate_name: &str,
         output_filenames: OutputFilenames,
     ) -> GlobalCtxt<'tcx> {
+        let ResolverOutputs {
+            definitions,
+            global_ctxt: untracked_resolutions,
+            ast_lowering: untracked_resolver_for_lowering,
+        } = resolver_outputs;
         let data_layout = TargetDataLayout::parse(&s.target).unwrap_or_else(|err| {
             s.emit_fatal(err);
         });
@@ -1253,7 +1242,7 @@ impl<'tcx> TyCtxt<'tcx> {
             &interners,
             s,
             &definitions,
-            &*cstore,
+            &*untracked_resolutions.cstore,
             // This is only used to create a stable hashing context.
             &untracked_resolutions.source_span,
         );
@@ -1268,7 +1257,6 @@ impl<'tcx> TyCtxt<'tcx> {
             interners,
             dep_graph,
             definitions: RwLock::new(definitions),
-            cstore,
             prof: s.prof.clone(),
             types: common_types,
             lifetimes: common_lifetimes,
@@ -1291,6 +1279,12 @@ impl<'tcx> TyCtxt<'tcx> {
         }
     }
 
+    /// Constructs a `TyKind::Error` type with current `ErrorGuaranteed`
+    #[track_caller]
+    pub fn ty_error_with_guaranteed(self, reported: ErrorGuaranteed) -> Ty<'tcx> {
+        self.mk_ty(Error(reported))
+    }
+
     /// Constructs a `TyKind::Error` type and registers a `delay_span_bug` to ensure it gets used.
     #[track_caller]
     pub fn ty_error(self) -> Ty<'tcx> {
@@ -1302,7 +1296,17 @@ impl<'tcx> TyCtxt<'tcx> {
     #[track_caller]
     pub fn ty_error_with_message<S: Into<MultiSpan>>(self, span: S, msg: &str) -> Ty<'tcx> {
         let reported = self.sess.delay_span_bug(span, msg);
-        self.mk_ty(Error(DelaySpanBugEmitted { reported, _priv: () }))
+        self.mk_ty(Error(reported))
+    }
+
+    /// Like [TyCtxt::ty_error] but for constants, with current `ErrorGuaranteed`
+    #[track_caller]
+    pub fn const_error_with_guaranteed(
+        self,
+        ty: Ty<'tcx>,
+        reported: ErrorGuaranteed,
+    ) -> Const<'tcx> {
+        self.mk_const(ty::ConstKind::Error(reported), ty)
     }
 
     /// Like [TyCtxt::ty_error] but for constants.
@@ -1324,10 +1328,7 @@ impl<'tcx> TyCtxt<'tcx> {
         msg: &str,
     ) -> Const<'tcx> {
         let reported = self.sess.delay_span_bug(span, msg);
-        self.mk_const(ty::ConstS {
-            kind: ty::ConstKind::Error(DelaySpanBugEmitted { reported, _priv: () }),
-            ty,
-        })
+        self.mk_const(ty::ConstKind::Error(reported), ty)
     }
 
     pub fn consider_optimizing<T: Fn() -> String>(self, msg: T) -> bool {
@@ -1369,7 +1370,7 @@ impl<'tcx> TyCtxt<'tcx> {
         if let Some(id) = id.as_local() {
             self.definitions_untracked().def_key(id)
         } else {
-            self.cstore.def_key(id)
+            self.untracked_resolutions.cstore.def_key(id)
         }
     }
 
@@ -1383,7 +1384,7 @@ impl<'tcx> TyCtxt<'tcx> {
         if let Some(id) = id.as_local() {
             self.definitions_untracked().def_path(id)
         } else {
-            self.cstore.def_path(id)
+            self.untracked_resolutions.cstore.def_path(id)
         }
     }
 
@@ -1393,7 +1394,7 @@ impl<'tcx> TyCtxt<'tcx> {
         if let Some(def_id) = def_id.as_local() {
             self.definitions_untracked().def_path_hash(def_id)
         } else {
-            self.cstore.def_path_hash(def_id)
+            self.untracked_resolutions.cstore.def_path_hash(def_id)
         }
     }
 
@@ -1402,7 +1403,7 @@ impl<'tcx> TyCtxt<'tcx> {
         if crate_num == LOCAL_CRATE {
             self.sess.local_stable_crate_id()
         } else {
-            self.cstore.stable_crate_id(crate_num)
+            self.untracked_resolutions.cstore.stable_crate_id(crate_num)
         }
     }
 
@@ -1413,7 +1414,7 @@ impl<'tcx> TyCtxt<'tcx> {
         if stable_crate_id == self.sess.local_stable_crate_id() {
             LOCAL_CRATE
         } else {
-            self.cstore.stable_crate_id_to_crate_num(stable_crate_id)
+            self.untracked_resolutions.cstore.stable_crate_id_to_crate_num(stable_crate_id)
         }
     }
 
@@ -1432,8 +1433,9 @@ impl<'tcx> TyCtxt<'tcx> {
         } else {
             // If this is a DefPathHash from an upstream crate, let the CrateStore map
             // it to a DefId.
-            let cnum = self.cstore.stable_crate_id_to_crate_num(stable_crate_id);
-            self.cstore.def_path_hash_to_def_id(cnum, hash)
+            let cstore = &*self.untracked_resolutions.cstore;
+            let cnum = cstore.stable_crate_id_to_crate_num(stable_crate_id);
+            cstore.def_path_hash_to_def_id(cnum, hash)
         }
     }
 
@@ -1445,7 +1447,7 @@ impl<'tcx> TyCtxt<'tcx> {
         let (crate_name, stable_crate_id) = if def_id.is_local() {
             (self.crate_name, self.sess.local_stable_crate_id())
         } else {
-            let cstore = &self.cstore;
+            let cstore = &*self.untracked_resolutions.cstore;
             (cstore.crate_name(def_id.krate), cstore.stable_crate_id(def_id.krate))
         };
 
@@ -1520,7 +1522,7 @@ impl<'tcx> TyCtxt<'tcx> {
     /// Note that this is *untracked* and should only be used within the query
     /// system if the result is otherwise tracked through queries
     pub fn cstore_untracked(self) -> &'tcx CrateStoreDyn {
-        &*self.cstore
+        &*self.untracked_resolutions.cstore
     }
 
     /// Note that this is *untracked* and should only be used within the query
@@ -1546,7 +1548,7 @@ impl<'tcx> TyCtxt<'tcx> {
         let hcx = StableHashingContext::new(
             self.sess,
             &*definitions,
-            &*self.cstore,
+            &*self.untracked_resolutions.cstore,
             &self.untracked_resolutions.source_span,
         );
         f(hcx)
@@ -2241,7 +2243,7 @@ macro_rules! direct_interners {
 
 direct_interners! {
     region: mk_region(RegionKind<'tcx>): Region -> Region<'tcx>,
-    const_: mk_const(ConstS<'tcx>): Const -> Const<'tcx>,
+    const_: mk_const_internal(ConstS<'tcx>): Const -> Const<'tcx>,
     const_allocation: intern_const_alloc(Allocation): ConstAllocation -> ConstAllocation<'tcx>,
     layout: intern_layout(LayoutS<'tcx>): Layout -> Layout<'tcx>,
     adt_def: intern_adt_def(AdtDefData): AdtDef -> AdtDef<'tcx>,
@@ -2364,7 +2366,7 @@ impl<'tcx> TyCtxt<'tcx> {
             st,
             self.sess,
             &self.definitions.read(),
-            &*self.cstore,
+            &*self.untracked_resolutions.cstore,
             // This is only used to create a stable hashing context.
             &self.untracked_resolutions.source_span,
         )
@@ -2454,7 +2456,7 @@ impl<'tcx> TyCtxt<'tcx> {
 
     #[inline]
     pub fn mk_lang_item(self, ty: Ty<'tcx>, item: LangItem) -> Option<Ty<'tcx>> {
-        let def_id = self.lang_items().require(item).ok()?;
+        let def_id = self.lang_items().get(item)?;
         Some(self.mk_generic_adt(def_id, ty))
     }
 
@@ -2579,9 +2581,14 @@ impl<'tcx> TyCtxt<'tcx> {
         self.mk_ty_infer(TyVar(v))
     }
 
+    #[inline]
+    pub fn mk_const(self, kind: ty::ConstKind<'tcx>, ty: Ty<'tcx>) -> Const<'tcx> {
+        self.mk_const_internal(ty::ConstS { kind, ty })
+    }
+
     #[inline]
     pub fn mk_const_var(self, v: ConstVid<'tcx>, ty: Ty<'tcx>) -> Const<'tcx> {
-        self.mk_const(ty::ConstS { kind: ty::ConstKind::Infer(InferConst::Var(v)), ty })
+        self.mk_const(ty::ConstKind::Infer(InferConst::Var(v)), ty)
     }
 
     #[inline]
@@ -2601,7 +2608,7 @@ impl<'tcx> TyCtxt<'tcx> {
 
     #[inline]
     pub fn mk_const_infer(self, ic: InferConst<'tcx>, ty: Ty<'tcx>) -> ty::Const<'tcx> {
-        self.mk_const(ty::ConstS { kind: ty::ConstKind::Infer(ic), ty })
+        self.mk_const(ty::ConstKind::Infer(ic), ty)
     }
 
     #[inline]
@@ -2611,7 +2618,7 @@ impl<'tcx> TyCtxt<'tcx> {
 
     #[inline]
     pub fn mk_const_param(self, index: u32, name: Symbol, ty: Ty<'tcx>) -> Const<'tcx> {
-        self.mk_const(ty::ConstS { kind: ty::ConstKind::Param(ParamConst { index, name }), ty })
+        self.mk_const(ty::ConstKind::Param(ParamConst { index, name }), ty)
     }
 
     pub fn mk_param_from_def(self, param: &ty::GenericParamDef) -> GenericArg<'tcx> {
@@ -2818,7 +2825,9 @@ impl<'tcx> TyCtxt<'tcx> {
         span: impl Into<MultiSpan>,
         decorator: impl for<'a> DecorateLint<'a, ()>,
     ) {
-        self.struct_span_lint_hir(lint, hir_id, span, decorator.msg(), |diag| {
+        let msg = decorator.msg();
+        let (level, src) = self.lint_level_at_node(lint, hir_id);
+        struct_lint_level(self.sess, lint, level, src, Some(span.into()), msg, |diag| {
             decorator.decorate_lint(diag)
         })
     }
@@ -2828,6 +2837,7 @@ impl<'tcx> TyCtxt<'tcx> {
     /// Return value of the `decorate` closure is ignored, see [`struct_lint_level`] for a detailed explanation.
     ///
     /// [`struct_lint_level`]: rustc_middle::lint::struct_lint_level#decorate-signature
+    #[rustc_lint_diagnostics]
     pub fn struct_span_lint_hir(
         self,
         lint: &'static Lint,
@@ -2858,6 +2868,7 @@ impl<'tcx> TyCtxt<'tcx> {
     /// Return value of the `decorate` closure is ignored, see [`struct_lint_level`] for a detailed explanation.
     ///
     /// [`struct_lint_level`]: rustc_middle::lint::struct_lint_level#decorate-signature
+    #[rustc_lint_diagnostics]
     pub fn struct_lint_node(
         self,
         lint: &'static Lint,
diff --git a/compiler/rustc_middle/src/ty/error.rs b/compiler/rustc_middle/src/ty/error.rs
index 52f16ad88f69..dc13374f992e 100644
--- a/compiler/rustc_middle/src/ty/error.rs
+++ b/compiler/rustc_middle/src/ty/error.rs
@@ -430,7 +430,9 @@ impl<'tcx> TyCtxt<'tcx> {
                     (ty::Projection(_), ty::Projection(_)) => {
                         diag.note("an associated type was expected, but a different one was found");
                     }
-                    (ty::Param(p), ty::Projection(proj)) | (ty::Projection(proj), ty::Param(p)) => {
+                    (ty::Param(p), ty::Projection(proj)) | (ty::Projection(proj), ty::Param(p))
+                        if self.def_kind(proj.item_def_id) != DefKind::ImplTraitPlaceholder =>
+                    {
                         let generics = self.generics_of(body_owner_def_id);
                         let p_span = self.def_span(generics.type_param(p, self).def_id);
                         if !sp.contains(p_span) {
@@ -872,9 +874,9 @@ fn foo(&self) -> Self::T { String::new() }
                             // FIXME: account for returning some type in a trait fn impl that has
                             // an assoc type as a return type (#72076).
                             if let hir::Defaultness::Default { has_value: true } =
-                                self.impl_defaultness(item.id.def_id)
+                                self.impl_defaultness(item.id.owner_id)
                             {
-                                if self.type_of(item.id.def_id) == found {
+                                if self.type_of(item.id.owner_id) == found {
                                     diag.span_label(
                                         item.span,
                                         "associated type defaults can't be assumed inside the \
@@ -894,7 +896,7 @@ fn foo(&self) -> Self::T { String::new() }
             })) => {
                 for item in &items[..] {
                     if let hir::AssocItemKind::Type = item.kind {
-                        if self.type_of(item.id.def_id) == found {
+                        if self.type_of(item.id.owner_id) == found {
                             diag.span_label(item.span, "expected this associated type");
                             return true;
                         }
diff --git a/compiler/rustc_middle/src/ty/fold.rs b/compiler/rustc_middle/src/ty/fold.rs
index 54f1499eb3d1..2842b3c3102d 100644
--- a/compiler/rustc_middle/src/ty/fold.rs
+++ b/compiler/rustc_middle/src/ty/fold.rs
@@ -566,10 +566,7 @@ impl<'tcx> TyCtxt<'tcx> {
                     ))
                 },
                 consts: &mut |c, ty: Ty<'tcx>| {
-                    self.mk_const(ty::ConstS {
-                        kind: ty::ConstKind::Bound(ty::INNERMOST, shift_bv(c)),
-                        ty,
-                    })
+                    self.mk_const(ty::ConstKind::Bound(ty::INNERMOST, shift_bv(c)), ty)
                 },
             },
         )
@@ -601,7 +598,7 @@ impl<'tcx> TyCtxt<'tcx> {
             .replace_late_bound_regions(sig, |_| {
                 let br = ty::BoundRegion {
                     var: ty::BoundVar::from_u32(counter),
-                    kind: ty::BrAnon(counter),
+                    kind: ty::BrAnon(counter, None),
                 };
                 let r = self.mk_region(ty::ReLateBound(ty::INNERMOST, br));
                 counter += 1;
@@ -609,7 +606,7 @@ impl<'tcx> TyCtxt<'tcx> {
             })
             .0;
         let bound_vars = self.mk_bound_variable_kinds(
-            (0..counter).map(|i| ty::BoundVariableKind::Region(ty::BrAnon(i))),
+            (0..counter).map(|i| ty::BoundVariableKind::Region(ty::BrAnon(i, None))),
         );
         Binder::bind_with_vars(inner, bound_vars)
     }
@@ -629,7 +626,9 @@ impl<'tcx> TyCtxt<'tcx> {
                 let index = entry.index();
                 let var = ty::BoundVar::from_usize(index);
                 let kind = entry
-                    .or_insert_with(|| ty::BoundVariableKind::Region(ty::BrAnon(index as u32)))
+                    .or_insert_with(|| {
+                        ty::BoundVariableKind::Region(ty::BrAnon(index as u32, None))
+                    })
                     .expect_region();
                 let br = ty::BoundRegion { var, kind };
                 self.tcx.mk_region(ty::ReLateBound(ty::INNERMOST, br))
@@ -648,7 +647,7 @@ impl<'tcx> TyCtxt<'tcx> {
                 let index = entry.index();
                 let var = ty::BoundVar::from_usize(index);
                 let () = entry.or_insert_with(|| ty::BoundVariableKind::Const).expect_const();
-                self.tcx.mk_const(ty::ConstS { ty, kind: ty::ConstKind::Bound(ty::INNERMOST, var) })
+                self.tcx.mk_const(ty::ConstKind::Bound(ty::INNERMOST, var), ty)
             }
         }
 
@@ -732,10 +731,7 @@ impl<'tcx> TypeFolder<'tcx> for Shifter<'tcx> {
                 ct
             } else {
                 let debruijn = debruijn.shifted_in(self.amount);
-                self.tcx.mk_const(ty::ConstS {
-                    kind: ty::ConstKind::Bound(debruijn, bound_ct),
-                    ty: ct.ty(),
-                })
+                self.tcx.mk_const(ty::ConstKind::Bound(debruijn, bound_ct), ct.ty())
             }
         } else {
             ct.super_fold_with(self)
diff --git a/compiler/rustc_middle/src/ty/instance.rs b/compiler/rustc_middle/src/ty/instance.rs
index 6c1414f7b8ac..ae0f158ede99 100644
--- a/compiler/rustc_middle/src/ty/instance.rs
+++ b/compiler/rustc_middle/src/ty/instance.rs
@@ -511,12 +511,12 @@ impl<'tcx> Instance<'tcx> {
         Instance::resolve(tcx, ty::ParamEnv::reveal_all(), def_id, substs).unwrap().unwrap()
     }
 
+    #[instrument(level = "debug", skip(tcx), ret)]
     pub fn fn_once_adapter_instance(
         tcx: TyCtxt<'tcx>,
         closure_did: DefId,
         substs: ty::SubstsRef<'tcx>,
     ) -> Option<Instance<'tcx>> {
-        debug!("fn_once_adapter_shim({:?}, {:?})", closure_did, substs);
         let fn_once = tcx.require_lang_item(LangItem::FnOnce, None);
         let call_once = tcx
             .associated_items(fn_once)
@@ -536,7 +536,7 @@ impl<'tcx> Instance<'tcx> {
         assert_eq!(sig.inputs().len(), 1);
         let substs = tcx.mk_substs_trait(self_ty, &[sig.inputs()[0].into()]);
 
-        debug!("fn_once_adapter_shim: self_ty={:?} sig={:?}", self_ty, sig);
+        debug!(?self_ty, ?sig);
         Some(Instance { def, substs })
     }
 
diff --git a/compiler/rustc_middle/src/ty/layout.rs b/compiler/rustc_middle/src/ty/layout.rs
index 0a109fd8f44f..c74d6bc3774a 100644
--- a/compiler/rustc_middle/src/ty/layout.rs
+++ b/compiler/rustc_middle/src/ty/layout.rs
@@ -189,8 +189,8 @@ pub enum LayoutError<'tcx> {
     NormalizationFailure(Ty<'tcx>, NormalizationError<'tcx>),
 }
 
-impl<'a> IntoDiagnostic<'a, !> for LayoutError<'a> {
-    fn into_diagnostic(self, handler: &'a Handler) -> DiagnosticBuilder<'a, !> {
+impl IntoDiagnostic<'_, !> for LayoutError<'_> {
+    fn into_diagnostic(self, handler: &Handler) -> DiagnosticBuilder<'_, !> {
         let mut diag = handler.struct_fatal("");
 
         match self {
@@ -830,7 +830,7 @@ where
                 } else {
                     match mt {
                         hir::Mutability::Not => {
-                            if ty.is_freeze(tcx.at(DUMMY_SP), cx.param_env()) {
+                            if ty.is_freeze(tcx, cx.param_env()) {
                                 PointerKind::Frozen
                             } else {
                                 PointerKind::SharedMutable
@@ -841,7 +841,7 @@ where
                             // noalias, as another pointer to the structure can be obtained, that
                             // is not based-on the original reference. We consider all !Unpin
                             // types to be potentially self-referential here.
-                            if ty.is_unpin(tcx.at(DUMMY_SP), cx.param_env()) {
+                            if ty.is_unpin(tcx, cx.param_env()) {
                                 PointerKind::UniqueBorrowed
                             } else {
                                 PointerKind::UniqueBorrowedPinned
@@ -1126,8 +1126,8 @@ impl<'tcx> fmt::Display for FnAbiError<'tcx> {
     }
 }
 
-impl<'tcx> IntoDiagnostic<'tcx, !> for FnAbiError<'tcx> {
-    fn into_diagnostic(self, handler: &'tcx Handler) -> DiagnosticBuilder<'tcx, !> {
+impl IntoDiagnostic<'_, !> for FnAbiError<'_> {
+    fn into_diagnostic(self, handler: &Handler) -> DiagnosticBuilder<'_, !> {
         handler.struct_fatal(self.to_string())
     }
 }
diff --git a/compiler/rustc_middle/src/ty/mod.rs b/compiler/rustc_middle/src/ty/mod.rs
index c2aef8178e2c..18eb06b83c9d 100644
--- a/compiler/rustc_middle/src/ty/mod.rs
+++ b/compiler/rustc_middle/src/ty/mod.rs
@@ -17,7 +17,7 @@ pub use self::IntVarValue::*;
 pub use self::Variance::*;
 use crate::error::{OpaqueHiddenTypeMismatch, TypeMismatchReason};
 use crate::metadata::ModChild;
-use crate::middle::privacy::AccessLevels;
+use crate::middle::privacy::EffectiveVisibilities;
 use crate::mir::{Body, GeneratorLayout};
 use crate::traits::{self, Reveal};
 use crate::ty;
@@ -38,11 +38,13 @@ use rustc_data_structures::tagged_ptr::CopyTaggedPtr;
 use rustc_hir as hir;
 use rustc_hir::def::{CtorKind, CtorOf, DefKind, LifetimeRes, Res};
 use rustc_hir::def_id::{CrateNum, DefId, LocalDefId, LocalDefIdMap};
+use rustc_hir::definitions::Definitions;
 use rustc_hir::Node;
 use rustc_index::vec::IndexVec;
 use rustc_macros::HashStable;
 use rustc_query_system::ich::StableHashingContext;
 use rustc_serialize::{Decodable, Encodable};
+use rustc_session::cstore::CrateStoreDyn;
 use rustc_span::hygiene::MacroKind;
 use rustc_span::symbol::{kw, sym, Ident, Symbol};
 use rustc_span::{ExpnId, Span};
@@ -78,7 +80,7 @@ pub use self::consts::{
 };
 pub use self::context::{
     tls, CanonicalUserType, CanonicalUserTypeAnnotation, CanonicalUserTypeAnnotations,
-    CtxtInterners, DeducedParamAttrs, DelaySpanBugEmitted, FreeRegionInfo, GeneratorDiagnosticData,
+    CtxtInterners, DeducedParamAttrs, FreeRegionInfo, GeneratorDiagnosticData,
     GeneratorInteriorTypeCause, GlobalCtxt, Lift, OnDiskCache, TyCtxt, TypeckResults, UserType,
     UserTypeAnnotationIndex,
 };
@@ -142,8 +144,15 @@ mod sty;
 
 pub type RegisteredTools = FxHashSet<Ident>;
 
-#[derive(Debug)]
 pub struct ResolverOutputs {
+    pub definitions: Definitions,
+    pub global_ctxt: ResolverGlobalCtxt,
+    pub ast_lowering: ResolverAstLowering,
+}
+
+#[derive(Debug)]
+pub struct ResolverGlobalCtxt {
+    pub cstore: Box<CrateStoreDyn>,
     pub visibilities: FxHashMap<LocalDefId, Visibility>,
     /// This field is used to decide whether we should make `PRIVATE_IN_PUBLIC` a hard error.
     pub has_pub_restricted: bool,
@@ -151,7 +160,7 @@ pub struct ResolverOutputs {
     pub expn_that_defined: FxHashMap<LocalDefId, ExpnId>,
     /// Reference span for definitions.
     pub source_span: IndexVec<LocalDefId, Span>,
-    pub access_levels: AccessLevels,
+    pub effective_visibilities: EffectiveVisibilities,
     pub extern_crate_map: FxHashMap<LocalDefId, CrateNum>,
     pub maybe_unused_trait_imports: FxIndexSet<LocalDefId>,
     pub maybe_unused_extern_crates: Vec<(LocalDefId, Span)>,
@@ -2497,6 +2506,10 @@ impl<'tcx> TyCtxt<'tcx> {
         self.trait_def(trait_def_id).has_auto_impl
     }
 
+    pub fn trait_is_coinductive(self, trait_def_id: DefId) -> bool {
+        self.trait_is_auto(trait_def_id) || self.lang_items().sized_trait() == Some(trait_def_id)
+    }
+
     /// Returns layout of a generator. Layout might be unavailable if the
     /// generator is tainted by errors.
     pub fn generator_layout(self, def_id: DefId) -> Option<&'tcx GeneratorLayout<'tcx>> {
@@ -2541,11 +2554,11 @@ impl<'tcx> TyCtxt<'tcx> {
 
     /// Looks up the span of `impl_did` if the impl is local; otherwise returns `Err`
     /// with the name of the crate containing the impl.
-    pub fn span_of_impl(self, impl_did: DefId) -> Result<Span, Symbol> {
-        if let Some(impl_did) = impl_did.as_local() {
-            Ok(self.def_span(impl_did))
+    pub fn span_of_impl(self, impl_def_id: DefId) -> Result<Span, Symbol> {
+        if let Some(impl_def_id) = impl_def_id.as_local() {
+            Ok(self.def_span(impl_def_id))
         } else {
-            Err(self.crate_name(impl_did.krate))
+            Err(self.crate_name(impl_def_id.krate))
         }
     }
 
@@ -2595,7 +2608,9 @@ impl<'tcx> TyCtxt<'tcx> {
             && if self.features().collapse_debuginfo {
                 span.in_macro_expansion_with_collapse_debuginfo()
             } else {
-                span.from_expansion()
+                // Inlined spans should not be collapsed as that leads to all of the
+                // inlined code being attributed to the inline callsite.
+                span.from_expansion() && !span.is_inlined()
             }
     }
 
diff --git a/compiler/rustc_middle/src/ty/print/pretty.rs b/compiler/rustc_middle/src/ty/print/pretty.rs
index b8ee2b994b1e..48e803597b02 100644
--- a/compiler/rustc_middle/src/ty/print/pretty.rs
+++ b/compiler/rustc_middle/src/ty/print/pretty.rs
@@ -596,7 +596,7 @@ pub trait PrettyPrinter<'tcx>:
             }
             ty::FnPtr(ref bare_fn) => p!(print(bare_fn)),
             ty::Infer(infer_ty) => {
-                let verbose = self.tcx().sess.verbose();
+                let verbose = self.should_print_verbose();
                 if let ty::TyVar(ty_vid) = infer_ty {
                     if let Some(name) = self.ty_infer_name(ty_vid) {
                         p!(write("{}", name))
@@ -638,7 +638,7 @@ pub trait PrettyPrinter<'tcx>:
                 p!(print_def_path(def_id, &[]));
             }
             ty::Projection(ref data) => {
-                if !(self.tcx().sess.verbose() || NO_QUERIES.with(|q| q.get()))
+                if !(self.should_print_verbose() || NO_QUERIES.with(|q| q.get()))
                     && self.tcx().def_kind(data.item_def_id) == DefKind::ImplTraitPlaceholder
                 {
                     return self.pretty_print_opaque_impl_type(data.item_def_id, data.substs);
@@ -654,7 +654,7 @@ pub trait PrettyPrinter<'tcx>:
                 // only affect certain debug messages (e.g. messages printed
                 // from `rustc_middle::ty` during the computation of `tcx.predicates_of`),
                 // and should have no effect on any compiler output.
-                if self.tcx().sess.verbose() || NO_QUERIES.with(|q| q.get()) {
+                if self.should_print_verbose() || NO_QUERIES.with(|q| q.get()) {
                     p!(write("Opaque({:?}, {:?})", def_id, substs));
                     return Ok(self);
                 }
@@ -685,7 +685,7 @@ pub trait PrettyPrinter<'tcx>:
                     hir::Movability::Static => p!("static "),
                 }
 
-                if !self.tcx().sess.verbose() {
+                if !self.should_print_verbose() {
                     p!("generator");
                     // FIXME(eddyb) should use `def_span`.
                     if let Some(did) = did.as_local() {
@@ -721,7 +721,7 @@ pub trait PrettyPrinter<'tcx>:
             }
             ty::Closure(did, substs) => {
                 p!(write("["));
-                if !self.tcx().sess.verbose() {
+                if !self.should_print_verbose() {
                     p!(write("closure"));
                     // FIXME(eddyb) should use `def_span`.
                     if let Some(did) = did.as_local() {
@@ -759,7 +759,7 @@ pub trait PrettyPrinter<'tcx>:
             }
             ty::Array(ty, sz) => {
                 p!("[", print(ty), "; ");
-                if self.tcx().sess.verbose() {
+                if self.should_print_verbose() {
                     p!(write("{:?}", sz));
                 } else if let ty::ConstKind::Unevaluated(..) = sz.kind() {
                     // Do not try to evaluate unevaluated constants. If we are const evaluating an
@@ -1073,7 +1073,7 @@ pub trait PrettyPrinter<'tcx>:
 
                 // Special-case `Fn(...) -> ...` and re-sugar it.
                 let fn_trait_kind = cx.tcx().fn_trait_kind_from_lang_item(principal.def_id);
-                if !cx.tcx().sess.verbose() && fn_trait_kind.is_some() {
+                if !cx.should_print_verbose() && fn_trait_kind.is_some() {
                     if let ty::Tuple(tys) = principal.substs.type_at(0).kind() {
                         let mut projections = predicates.projection_bounds();
                         if let (Some(proj), None) = (projections.next(), projections.next()) {
@@ -1137,7 +1137,7 @@ pub trait PrettyPrinter<'tcx>:
         //
         // To avoid causing instabilities in compiletest
         // output, sort the auto-traits alphabetically.
-        auto_traits.sort_by_cached_key(|did| self.tcx().def_path_str(*did));
+        auto_traits.sort_by_cached_key(|did| with_no_trimmed_paths!(self.tcx().def_path_str(*did)));
 
         for def_id in auto_traits {
             if !first {
@@ -1181,7 +1181,7 @@ pub trait PrettyPrinter<'tcx>:
     ) -> Result<Self::Const, Self::Error> {
         define_scoped_cx!(self);
 
-        if self.tcx().sess.verbose() {
+        if self.should_print_verbose() {
             p!(write("Const({:?}: {:?})", ct.kind(), ct.ty()));
             return Ok(self);
         }
@@ -1416,7 +1416,7 @@ pub trait PrettyPrinter<'tcx>:
     ) -> Result<Self::Const, Self::Error> {
         define_scoped_cx!(self);
 
-        if self.tcx().sess.verbose() {
+        if self.should_print_verbose() {
             p!(write("ValTree({:?}: ", valtree), print(ty), ")");
             return Ok(self);
         }
@@ -1560,6 +1560,10 @@ pub trait PrettyPrinter<'tcx>:
             Ok(cx)
         })
     }
+
+    fn should_print_verbose(&self) -> bool {
+        self.tcx().sess.verbose()
+    }
 }
 
 // HACK(eddyb) boxed to avoid moving around a large struct by-value.
@@ -1655,6 +1659,12 @@ impl<'t> TyCtxt<'t> {
         debug!("def_path_str: def_id={:?}, ns={:?}", def_id, ns);
         FmtPrinter::new(self, ns).print_def_path(def_id, substs).unwrap().into_buffer()
     }
+
+    pub fn value_path_str_with_substs(self, def_id: DefId, substs: &'t [GenericArg<'t>]) -> String {
+        let ns = guess_def_namespace(self, def_id);
+        debug!("value_path_str: def_id={:?}, ns={:?}", def_id, ns);
+        FmtPrinter::new(self, ns).print_value_path(def_id, substs).unwrap().into_buffer()
+    }
 }
 
 impl fmt::Write for FmtPrinter<'_, '_> {
@@ -1835,7 +1845,7 @@ impl<'tcx> Printer<'tcx> for FmtPrinter<'_, 'tcx> {
             }
         }
 
-        let verbose = self.tcx.sess.verbose();
+        let verbose = self.should_print_verbose();
         disambiguated_data.fmt_maybe_verbose(&mut self, verbose)?;
 
         self.empty_path = false;
@@ -1936,7 +1946,7 @@ impl<'tcx> PrettyPrinter<'tcx> for FmtPrinter<'_, 'tcx> {
             return true;
         }
 
-        if self.tcx.sess.verbose() {
+        if self.should_print_verbose() {
             return true;
         }
 
@@ -2008,7 +2018,7 @@ impl<'tcx> FmtPrinter<'_, 'tcx> {
             return Ok(self);
         }
 
-        if self.tcx.sess.verbose() {
+        if self.should_print_verbose() {
             p!(write("{:?}", region));
             return Ok(self);
         }
@@ -2111,7 +2121,7 @@ impl<'a, 'tcx> ty::TypeFolder<'tcx> for RegionFolder<'a, 'tcx> {
                 // If this is an anonymous placeholder, don't rename. Otherwise, in some
                 // async fns, we get a `for<'r> Send` bound
                 match kind {
-                    ty::BrAnon(_) | ty::BrEnv => r,
+                    ty::BrAnon(..) | ty::BrEnv => r,
                     _ => {
                         // Index doesn't matter, since this is just for naming and these never get bound
                         let br = ty::BoundRegion { var: ty::BoundVar::from_u32(0), kind };
@@ -2214,47 +2224,13 @@ impl<'tcx> FmtPrinter<'_, 'tcx> {
         // aren't named. Eventually, we might just want this as the default, but
         // this is not *quite* right and changes the ordering of some output
         // anyways.
-        let (new_value, map) = if self.tcx().sess.verbose() {
-            let regions: Vec<_> = value
-                .bound_vars()
-                .into_iter()
-                .map(|var| {
-                    let ty::BoundVariableKind::Region(var) = var else {
-                    // This doesn't really matter because it doesn't get used,
-                    // it's just an empty value
-                    return ty::BrAnon(0);
-                };
-                    match var {
-                        ty::BrAnon(_) | ty::BrEnv => {
-                            start_or_continue(&mut self, "for<", ", ");
-                            let name = next_name(&self);
-                            debug!(?name);
-                            do_continue(&mut self, name);
-                            ty::BrNamed(CRATE_DEF_ID.to_def_id(), name)
-                        }
-                        ty::BrNamed(def_id, kw::UnderscoreLifetime) => {
-                            start_or_continue(&mut self, "for<", ", ");
-                            let name = next_name(&self);
-                            do_continue(&mut self, name);
-                            ty::BrNamed(def_id, name)
-                        }
-                        ty::BrNamed(def_id, name) => {
-                            start_or_continue(&mut self, "for<", ", ");
-                            do_continue(&mut self, name);
-                            ty::BrNamed(def_id, name)
-                        }
-                    }
-                })
-                .collect();
+        let (new_value, map) = if self.should_print_verbose() {
+            for var in value.bound_vars().iter() {
+                start_or_continue(&mut self, "for<", ", ");
+                write!(self, "{:?}", var)?;
+            }
             start_or_continue(&mut self, "", "> ");
-
-            self.tcx.replace_late_bound_regions(value.clone(), |br| {
-                let kind = regions[br.var.as_usize()];
-                self.tcx.mk_region(ty::ReLateBound(
-                    ty::INNERMOST,
-                    ty::BoundRegion { var: br.var, kind },
-                ))
-            })
+            (value.clone().skip_binder(), BTreeMap::default())
         } else {
             let tcx = self.tcx;
 
@@ -2267,7 +2243,7 @@ impl<'tcx> FmtPrinter<'_, 'tcx> {
                             binder_level_idx: ty::DebruijnIndex,
                             br: ty::BoundRegion| {
                 let (name, kind) = match br.kind {
-                    ty::BrAnon(_) | ty::BrEnv => {
+                    ty::BrAnon(..) | ty::BrEnv => {
                         let name = next_name(&self);
 
                         if let Some(lt_idx) = lifetime_idx {
@@ -2736,7 +2712,7 @@ fn for_each_def(tcx: TyCtxt<'_>, mut collect_fn: impl for<'b> FnMut(&'b Ident, N
     // Iterate all local crate items no matter where they are defined.
     let hir = tcx.hir();
     for id in hir.items() {
-        if matches!(tcx.def_kind(id.def_id), DefKind::Use) {
+        if matches!(tcx.def_kind(id.owner_id), DefKind::Use) {
             continue;
         }
 
@@ -2745,7 +2721,7 @@ fn for_each_def(tcx: TyCtxt<'_>, mut collect_fn: impl for<'b> FnMut(&'b Ident, N
             continue;
         }
 
-        let def_id = item.def_id.to_def_id();
+        let def_id = item.owner_id.to_def_id();
         let ns = tcx.def_kind(def_id).ns().unwrap_or(Namespace::TypeNS);
         collect_fn(&item.ident, ns, def_id);
     }
diff --git a/compiler/rustc_middle/src/ty/query.rs b/compiler/rustc_middle/src/ty/query.rs
index 9c97ce34f29e..ec90590ada2e 100644
--- a/compiler/rustc_middle/src/ty/query.rs
+++ b/compiler/rustc_middle/src/ty/query.rs
@@ -5,7 +5,7 @@ use crate::metadata::ModChild;
 use crate::middle::codegen_fn_attrs::CodegenFnAttrs;
 use crate::middle::exported_symbols::{ExportedSymbol, SymbolExportInfo};
 use crate::middle::lib_features::LibFeatures;
-use crate::middle::privacy::AccessLevels;
+use crate::middle::privacy::EffectiveVisibilities;
 use crate::middle::resolve_lifetime::{ObjectLifetimeDefault, Region, ResolveLifetimes};
 use crate::middle::stability::{self, DeprecationEntry};
 use crate::mir;
@@ -40,6 +40,7 @@ use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexMap, FxIndexSet};
 use rustc_data_structures::steal::Steal;
 use rustc_data_structures::svh::Svh;
 use rustc_data_structures::sync::Lrc;
+use rustc_data_structures::unord::UnordSet;
 use rustc_errors::ErrorGuaranteed;
 use rustc_hir as hir;
 use rustc_hir::def::DefKind;
diff --git a/compiler/rustc_middle/src/ty/relate.rs b/compiler/rustc_middle/src/ty/relate.rs
index cdb618e030af..c083a405e3cf 100644
--- a/compiler/rustc_middle/src/ty/relate.rs
+++ b/compiler/rustc_middle/src/ty/relate.rs
@@ -574,8 +574,8 @@ pub fn super_relate_tys<'tcx, R: TypeRelation<'tcx>>(
 /// it.
 pub fn super_relate_consts<'tcx, R: TypeRelation<'tcx>>(
     relation: &mut R,
-    a: ty::Const<'tcx>,
-    b: ty::Const<'tcx>,
+    mut a: ty::Const<'tcx>,
+    mut b: ty::Const<'tcx>,
 ) -> RelateResult<'tcx, ty::Const<'tcx>> {
     debug!("{}.super_relate_consts(a = {:?}, b = {:?})", relation.tag(), a, b);
     let tcx = relation.tcx();
@@ -596,6 +596,17 @@ pub fn super_relate_consts<'tcx, R: TypeRelation<'tcx>>(
         );
     }
 
+    // HACK(const_generics): We still need to eagerly evaluate consts when
+    // relating them because during `normalize_param_env_or_error`,
+    // we may relate an evaluated constant in a obligation against
+    // an unnormalized (i.e. unevaluated) const in the param-env.
+    // FIXME(generic_const_exprs): Once we always lazily unify unevaluated constants
+    // these `eval` calls can be removed.
+    if !relation.tcx().features().generic_const_exprs {
+        a = a.eval(tcx, relation.param_env());
+        b = b.eval(tcx, relation.param_env());
+    }
+
     // Currently, the values that can be unified are primitive types,
     // and those that derive both `PartialEq` and `Eq`, corresponding
     // to structural-match types.
@@ -628,10 +639,10 @@ pub fn super_relate_consts<'tcx, R: TypeRelation<'tcx>>(
                 au.substs,
                 bu.substs,
             )?;
-            return Ok(tcx.mk_const(ty::ConstS {
-                kind: ty::ConstKind::Unevaluated(ty::UnevaluatedConst { def: au.def, substs }),
-                ty: a.ty(),
-            }));
+            return Ok(tcx.mk_const(
+                ty::ConstKind::Unevaluated(ty::UnevaluatedConst { def: au.def, substs }),
+                a.ty(),
+            ));
         }
         _ => false,
     };
diff --git a/compiler/rustc_middle/src/ty/structural_impls.rs b/compiler/rustc_middle/src/ty/structural_impls.rs
index 2cad333e3f52..9f0598d0ba86 100644
--- a/compiler/rustc_middle/src/ty/structural_impls.rs
+++ b/compiler/rustc_middle/src/ty/structural_impls.rs
@@ -68,7 +68,7 @@ impl<'tcx> fmt::Debug for ty::adjustment::Adjustment<'tcx> {
 impl fmt::Debug for ty::BoundRegionKind {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match *self {
-            ty::BrAnon(n) => write!(f, "BrAnon({:?})", n),
+            ty::BrAnon(n, span) => write!(f, "BrAnon({n:?}, {span:?})"),
             ty::BrNamed(did, name) => {
                 if did.is_crate_root() {
                     write!(f, "BrNamed({})", name)
@@ -240,7 +240,6 @@ TrivialTypeTraversalAndLiftImpls! {
     Field,
     interpret::Scalar,
     rustc_target::abi::Size,
-    ty::DelaySpanBugEmitted,
     rustc_type_ir::DebruijnIndex,
     ty::BoundVar,
     ty::Placeholder<ty::BoundVar>,
@@ -806,7 +805,7 @@ impl<'tcx> TypeSuperFoldable<'tcx> for ty::Const<'tcx> {
         let ty = self.ty().try_fold_with(folder)?;
         let kind = self.kind().try_fold_with(folder)?;
         if ty != self.ty() || kind != self.kind() {
-            Ok(folder.tcx().mk_const(ty::ConstS { ty, kind }))
+            Ok(folder.tcx().mk_const(kind, ty))
         } else {
             Ok(self)
         }
diff --git a/compiler/rustc_middle/src/ty/sty.rs b/compiler/rustc_middle/src/ty/sty.rs
index cf420bafeb12..49d82b503a4b 100644
--- a/compiler/rustc_middle/src/ty/sty.rs
+++ b/compiler/rustc_middle/src/ty/sty.rs
@@ -20,6 +20,7 @@ use rustc_hir::def_id::DefId;
 use rustc_index::vec::Idx;
 use rustc_macros::HashStable;
 use rustc_span::symbol::{kw, sym, Symbol};
+use rustc_span::Span;
 use rustc_target::abi::VariantIdx;
 use rustc_target::spec::abi;
 use std::borrow::Cow;
@@ -58,7 +59,7 @@ pub struct FreeRegion {
 #[derive(HashStable)]
 pub enum BoundRegionKind {
     /// An anonymous region parameter for a given fn (&T)
-    BrAnon(u32),
+    BrAnon(u32, Option<Span>),
 
     /// Named region parameters for functions (a in &'a T)
     ///
@@ -1282,6 +1283,12 @@ impl<'tcx> ParamTy {
     pub fn to_ty(self, tcx: TyCtxt<'tcx>) -> Ty<'tcx> {
         tcx.mk_ty_param(self.index, self.name)
     }
+
+    pub fn span_from_generics(&self, tcx: TyCtxt<'tcx>, item_with_generics: DefId) -> Span {
+        let generics = tcx.generics_of(item_with_generics);
+        let type_param = generics.type_param(self, tcx);
+        tcx.def_span(type_param.def_id)
+    }
 }
 
 #[derive(Copy, Clone, Hash, TyEncodable, TyDecodable, Eq, PartialEq, Ord, PartialOrd)]
diff --git a/compiler/rustc_middle/src/ty/subst.rs b/compiler/rustc_middle/src/ty/subst.rs
index 0660e9b79a70..c1cf7896db59 100644
--- a/compiler/rustc_middle/src/ty/subst.rs
+++ b/compiler/rustc_middle/src/ty/subst.rs
@@ -6,7 +6,6 @@ use crate::ty::sty::{ClosureSubsts, GeneratorSubsts, InlineConstSubsts};
 use crate::ty::visit::{TypeVisitable, TypeVisitor};
 use crate::ty::{self, Lift, List, ParamConst, Ty, TyCtxt};
 
-use rustc_data_structures::captures::Captures;
 use rustc_data_structures::intern::{Interned, WithStableHash};
 use rustc_hir::def_id::DefId;
 use rustc_macros::HashStable;
@@ -19,7 +18,7 @@ use std::fmt;
 use std::marker::PhantomData;
 use std::mem;
 use std::num::NonZeroUsize;
-use std::ops::ControlFlow;
+use std::ops::{ControlFlow, Deref};
 use std::slice;
 
 /// An entity in the Rust type system, which can be one of
@@ -506,6 +505,9 @@ impl<'tcx, T: TypeVisitable<'tcx>> TypeVisitable<'tcx> for &'tcx ty::List<T> {
     }
 }
 
+/// Similar to [`super::Binder`] except that it tracks early bound generics, i.e. `struct Foo<T>(T)`
+/// needs `T` substituted immediately. This type primarily exists to avoid forgetting to call
+/// `subst`.
 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Debug)]
 #[derive(Encodable, Decodable, HashStable)]
 pub struct EarlyBinder<T>(pub T);
@@ -559,25 +561,86 @@ impl<T, U> EarlyBinder<(T, U)> {
     }
 }
 
-impl<'tcx, 's, T: IntoIterator<Item = I>, I: TypeFoldable<'tcx>> EarlyBinder<T> {
+impl<'tcx, 's, I: IntoIterator> EarlyBinder<I>
+where
+    I::Item: TypeFoldable<'tcx>,
+{
     pub fn subst_iter(
         self,
         tcx: TyCtxt<'tcx>,
         substs: &'s [GenericArg<'tcx>],
-    ) -> impl Iterator<Item = I> + Captures<'s> + Captures<'tcx> {
-        self.0.into_iter().map(move |t| EarlyBinder(t).subst(tcx, substs))
+    ) -> SubstIter<'s, 'tcx, I> {
+        SubstIter { it: self.0.into_iter(), tcx, substs }
     }
 }
 
-impl<'tcx, 's, 'a, T: IntoIterator<Item = &'a I>, I: Copy + TypeFoldable<'tcx> + 'a>
-    EarlyBinder<T>
+pub struct SubstIter<'s, 'tcx, I: IntoIterator> {
+    it: I::IntoIter,
+    tcx: TyCtxt<'tcx>,
+    substs: &'s [GenericArg<'tcx>],
+}
+
+impl<'tcx, I: IntoIterator> Iterator for SubstIter<'_, 'tcx, I>
+where
+    I::Item: TypeFoldable<'tcx>,
+{
+    type Item = I::Item;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        Some(EarlyBinder(self.it.next()?).subst(self.tcx, self.substs))
+    }
+}
+
+impl<'tcx, I: IntoIterator> DoubleEndedIterator for SubstIter<'_, 'tcx, I>
+where
+    I::IntoIter: DoubleEndedIterator,
+    I::Item: TypeFoldable<'tcx>,
+{
+    fn next_back(&mut self) -> Option<Self::Item> {
+        Some(EarlyBinder(self.it.next_back()?).subst(self.tcx, self.substs))
+    }
+}
+
+impl<'tcx, 's, I: IntoIterator> EarlyBinder<I>
+where
+    I::Item: Deref,
+    <I::Item as Deref>::Target: Copy + TypeFoldable<'tcx>,
 {
     pub fn subst_iter_copied(
         self,
         tcx: TyCtxt<'tcx>,
         substs: &'s [GenericArg<'tcx>],
-    ) -> impl Iterator<Item = I> + Captures<'s> + Captures<'tcx> + Captures<'a> {
-        self.0.into_iter().map(move |t| EarlyBinder(*t).subst(tcx, substs))
+    ) -> SubstIterCopied<'s, 'tcx, I> {
+        SubstIterCopied { it: self.0.into_iter(), tcx, substs }
+    }
+}
+
+pub struct SubstIterCopied<'a, 'tcx, I: IntoIterator> {
+    it: I::IntoIter,
+    tcx: TyCtxt<'tcx>,
+    substs: &'a [GenericArg<'tcx>],
+}
+
+impl<'tcx, I: IntoIterator> Iterator for SubstIterCopied<'_, 'tcx, I>
+where
+    I::Item: Deref,
+    <I::Item as Deref>::Target: Copy + TypeFoldable<'tcx>,
+{
+    type Item = <I::Item as Deref>::Target;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        Some(EarlyBinder(*self.it.next()?).subst(self.tcx, self.substs))
+    }
+}
+
+impl<'tcx, I: IntoIterator> DoubleEndedIterator for SubstIterCopied<'_, 'tcx, I>
+where
+    I::IntoIter: DoubleEndedIterator,
+    I::Item: Deref,
+    <I::Item as Deref>::Target: Copy + TypeFoldable<'tcx>,
+{
+    fn next_back(&mut self) -> Option<Self::Item> {
+        Some(EarlyBinder(*self.it.next_back()?).subst(self.tcx, self.substs))
     }
 }
 
diff --git a/compiler/rustc_middle/src/ty/util.rs b/compiler/rustc_middle/src/ty/util.rs
index f73d062ba30a..f72e236eda13 100644
--- a/compiler/rustc_middle/src/ty/util.rs
+++ b/compiler/rustc_middle/src/ty/util.rs
@@ -2,7 +2,6 @@
 
 use crate::middle::codegen_fn_attrs::CodegenFnAttrFlags;
 use crate::ty::layout::IntegerExt;
-use crate::ty::query::TyCtxtAt;
 use crate::ty::{
     self, DefIdTree, FallibleTypeFolder, Ty, TyCtxt, TypeFoldable, TypeFolder, TypeSuperFoldable,
     TypeVisitable,
@@ -821,12 +820,8 @@ impl<'tcx> Ty<'tcx> {
     /// does copies even when the type actually doesn't satisfy the
     /// full requirements for the `Copy` trait (cc #29149) -- this
     /// winds up being reported as an error during NLL borrow check.
-    pub fn is_copy_modulo_regions(
-        self,
-        tcx_at: TyCtxtAt<'tcx>,
-        param_env: ty::ParamEnv<'tcx>,
-    ) -> bool {
-        self.is_trivially_pure_clone_copy() || tcx_at.is_copy_raw(param_env.and(self))
+    pub fn is_copy_modulo_regions(self, tcx: TyCtxt<'tcx>, param_env: ty::ParamEnv<'tcx>) -> bool {
+        self.is_trivially_pure_clone_copy() || tcx.is_copy_raw(param_env.and(self))
     }
 
     /// Checks whether values of this type `T` have a size known at
@@ -835,8 +830,8 @@ impl<'tcx> Ty<'tcx> {
     /// over-approximation in generic contexts, where one can have
     /// strange rules like `<T as Foo<'static>>::Bar: Sized` that
     /// actually carry lifetime requirements.
-    pub fn is_sized(self, tcx_at: TyCtxtAt<'tcx>, param_env: ty::ParamEnv<'tcx>) -> bool {
-        self.is_trivially_sized(tcx_at.tcx) || tcx_at.is_sized_raw(param_env.and(self))
+    pub fn is_sized(self, tcx: TyCtxt<'tcx>, param_env: ty::ParamEnv<'tcx>) -> bool {
+        self.is_trivially_sized(tcx) || tcx.is_sized_raw(param_env.and(self))
     }
 
     /// Checks whether values of this type `T` implement the `Freeze`
@@ -846,8 +841,8 @@ impl<'tcx> Ty<'tcx> {
     /// optimization as well as the rules around static values. Note
     /// that the `Freeze` trait is not exposed to end users and is
     /// effectively an implementation detail.
-    pub fn is_freeze(self, tcx_at: TyCtxtAt<'tcx>, param_env: ty::ParamEnv<'tcx>) -> bool {
-        self.is_trivially_freeze() || tcx_at.is_freeze_raw(param_env.and(self))
+    pub fn is_freeze(self, tcx: TyCtxt<'tcx>, param_env: ty::ParamEnv<'tcx>) -> bool {
+        self.is_trivially_freeze() || tcx.is_freeze_raw(param_env.and(self))
     }
 
     /// Fast path helper for testing if a type is `Freeze`.
@@ -886,8 +881,8 @@ impl<'tcx> Ty<'tcx> {
     }
 
     /// Checks whether values of this type `T` implement the `Unpin` trait.
-    pub fn is_unpin(self, tcx_at: TyCtxtAt<'tcx>, param_env: ty::ParamEnv<'tcx>) -> bool {
-        self.is_trivially_unpin() || tcx_at.is_unpin_raw(param_env.and(self))
+    pub fn is_unpin(self, tcx: TyCtxt<'tcx>, param_env: ty::ParamEnv<'tcx>) -> bool {
+        self.is_trivially_unpin() || tcx.is_unpin_raw(param_env.and(self))
     }
 
     /// Fast path helper for testing if a type is `Unpin`.
diff --git a/compiler/rustc_middle/src/ty/visit.rs b/compiler/rustc_middle/src/ty/visit.rs
index c09f71f9a6d0..5e366ef703f2 100644
--- a/compiler/rustc_middle/src/ty/visit.rs
+++ b/compiler/rustc_middle/src/ty/visit.rs
@@ -95,11 +95,15 @@ pub trait TypeVisitable<'tcx>: fmt::Debug + Clone {
     fn references_error(&self) -> bool {
         self.has_type_flags(TypeFlags::HAS_ERROR)
     }
-    fn error_reported(&self) -> Option<ErrorGuaranteed> {
+    fn error_reported(&self) -> Result<(), ErrorGuaranteed> {
         if self.references_error() {
-            Some(ErrorGuaranteed::unchecked_claim_error_was_emitted())
+            if let Some(reported) = ty::tls::with(|tcx| tcx.sess.has_errors()) {
+                Err(reported)
+            } else {
+                bug!("expect tcx.sess.has_errors return true");
+            }
         } else {
-            None
+            Ok(())
         }
     }
     fn has_non_region_param(&self) -> bool {
diff --git a/compiler/rustc_middle/src/ty/vtable.rs b/compiler/rustc_middle/src/ty/vtable.rs
index 5ca51c25a9ce..6eae94511e4d 100644
--- a/compiler/rustc_middle/src/ty/vtable.rs
+++ b/compiler/rustc_middle/src/ty/vtable.rs
@@ -66,7 +66,7 @@ pub(super) fn vtable_allocation_provider<'tcx>(
     let layout = tcx
         .layout_of(ty::ParamEnv::reveal_all().and(ty))
         .expect("failed to build vtable representation");
-    assert!(!layout.is_unsized(), "can't create a vtable for an unsized type");
+    assert!(layout.is_sized(), "can't create a vtable for an unsized type");
     let size = layout.size.bytes();
     let align = layout.align.abi.bytes();
 
diff --git a/compiler/rustc_middle/src/values.rs b/compiler/rustc_middle/src/values.rs
index f4b4c3fb05a7..f4562cdfb88d 100644
--- a/compiler/rustc_middle/src/values.rs
+++ b/compiler/rustc_middle/src/values.rs
@@ -185,7 +185,8 @@ fn find_item_ty_spans(
                 });
                 if check_params && let Some(args) = path.segments.last().unwrap().args {
                     let params_in_repr = tcx.params_in_repr(def_id);
-                    for (i, arg) in args.args.iter().enumerate() {
+                    // the domain size check is needed because the HIR may not be well-formed at this point
+                    for (i, arg) in args.args.iter().enumerate().take(params_in_repr.domain_size()) {
                         if let hir::GenericArg::Type(ty) = arg && params_in_repr.contains(i as u32) {
                             find_item_ty_spans(tcx, ty, needle, spans, seen_representable);
                         }
diff --git a/compiler/rustc_mir_build/src/build/block.rs b/compiler/rustc_mir_build/src/build/block.rs
index 183db56d7a08..db05592ed0ea 100644
--- a/compiler/rustc_mir_build/src/build/block.rs
+++ b/compiler/rustc_mir_build/src/build/block.rs
@@ -118,7 +118,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                     else_block: Some(else_block),
                 } => {
                     // When lowering the statement `let <pat> = <expr> else { <else> };`,
-                    // the `<else>` block is nested in the parent scope enclosing this statment.
+                    // the `<else>` block is nested in the parent scope enclosing this statement.
                     // That scope is usually either the enclosing block scope,
                     // or the remainder scope of the last statement.
                     // This is to make sure that temporaries instantiated in `<expr>` are dropped
diff --git a/compiler/rustc_mir_build/src/build/custom/mod.rs b/compiler/rustc_mir_build/src/build/custom/mod.rs
new file mode 100644
index 000000000000..68d8766c9073
--- /dev/null
+++ b/compiler/rustc_mir_build/src/build/custom/mod.rs
@@ -0,0 +1,155 @@
+//! Provides the implementation of the `custom_mir` attribute.
+//!
+//! Up until MIR building, this attribute has absolutely no effect. The `mir!` macro is a normal
+//! decl macro that expands like any other, and the code goes through parsing, name resolution and
+//! type checking like all other code. In MIR building we finally detect whether this attribute is
+//! present, and if so we branch off into this module, which implements the attribute by
+//! implementing a custom lowering from THIR to MIR.
+//!
+//! The result of this lowering is returned "normally" from the `mir_built` query, with the only
+//! notable difference being that the `injected` field in the body is set. Various components of the
+//! MIR pipeline, like borrowck and the pass manager will then consult this field (via
+//! `body.should_skip()`) to skip the parts of the MIR pipeline that precede the MIR phase the user
+//! specified.
+//!
+//! This file defines the general framework for the custom parsing. The parsing for all the
+//! "top-level" constructs can be found in the `parse` submodule, while the parsing for statements,
+//! terminators, and everything below can be found in the `parse::instruction` submodule.
+//!
+
+use rustc_ast::Attribute;
+use rustc_data_structures::fx::FxHashMap;
+use rustc_hir::def_id::DefId;
+use rustc_index::vec::IndexVec;
+use rustc_middle::{
+    mir::*,
+    thir::*,
+    ty::{Ty, TyCtxt},
+};
+use rustc_span::Span;
+
+mod parse;
+
+pub(super) fn build_custom_mir<'tcx>(
+    tcx: TyCtxt<'tcx>,
+    did: DefId,
+    thir: &Thir<'tcx>,
+    expr: ExprId,
+    params: &IndexVec<ParamId, Param<'tcx>>,
+    return_ty: Ty<'tcx>,
+    return_ty_span: Span,
+    span: Span,
+    attr: &Attribute,
+) -> Body<'tcx> {
+    let mut body = Body {
+        basic_blocks: BasicBlocks::new(IndexVec::new()),
+        source: MirSource::item(did),
+        phase: MirPhase::Built,
+        source_scopes: IndexVec::new(),
+        generator: None,
+        local_decls: LocalDecls::new(),
+        user_type_annotations: IndexVec::new(),
+        arg_count: params.len(),
+        spread_arg: None,
+        var_debug_info: Vec::new(),
+        span,
+        required_consts: Vec::new(),
+        is_polymorphic: false,
+        tainted_by_errors: None,
+        injection_phase: None,
+        pass_count: 1,
+    };
+
+    body.local_decls.push(LocalDecl::new(return_ty, return_ty_span));
+    body.basic_blocks_mut().push(BasicBlockData::new(None));
+    body.source_scopes.push(SourceScopeData {
+        span,
+        parent_scope: None,
+        inlined: None,
+        inlined_parent_scope: None,
+        local_data: ClearCrossCrate::Clear,
+    });
+    body.injection_phase = Some(parse_attribute(attr));
+
+    let mut pctxt = ParseCtxt {
+        tcx,
+        thir,
+        source_info: SourceInfo { span, scope: OUTERMOST_SOURCE_SCOPE },
+        body: &mut body,
+        local_map: FxHashMap::default(),
+        block_map: FxHashMap::default(),
+    };
+
+    let res = (|| {
+        pctxt.parse_args(&params)?;
+        pctxt.parse_body(expr)
+    })();
+    if let Err(err) = res {
+        tcx.sess.diagnostic().span_fatal(
+            err.span,
+            format!("Could not parse {}, found: {:?}", err.expected, err.item_description),
+        )
+    }
+
+    body
+}
+
+fn parse_attribute(attr: &Attribute) -> MirPhase {
+    let meta_items = attr.meta_item_list().unwrap();
+    let mut dialect: Option<String> = None;
+    let mut phase: Option<String> = None;
+
+    for nested in meta_items {
+        let name = nested.name_or_empty();
+        let value = nested.value_str().unwrap().as_str().to_string();
+        match name.as_str() {
+            "dialect" => {
+                assert!(dialect.is_none());
+                dialect = Some(value);
+            }
+            "phase" => {
+                assert!(phase.is_none());
+                phase = Some(value);
+            }
+            other => {
+                panic!("Unexpected key {}", other);
+            }
+        }
+    }
+
+    let Some(dialect) = dialect else {
+        assert!(phase.is_none());
+        return MirPhase::Built;
+    };
+
+    MirPhase::parse(dialect, phase)
+}
+
+struct ParseCtxt<'tcx, 'body> {
+    tcx: TyCtxt<'tcx>,
+    thir: &'body Thir<'tcx>,
+    source_info: SourceInfo,
+
+    body: &'body mut Body<'tcx>,
+    local_map: FxHashMap<LocalVarId, Local>,
+    block_map: FxHashMap<LocalVarId, BasicBlock>,
+}
+
+struct ParseError {
+    span: Span,
+    item_description: String,
+    expected: String,
+}
+
+impl<'tcx, 'body> ParseCtxt<'tcx, 'body> {
+    fn expr_error(&self, expr: ExprId, expected: &'static str) -> ParseError {
+        let expr = &self.thir[expr];
+        ParseError {
+            span: expr.span,
+            item_description: format!("{:?}", expr.kind),
+            expected: expected.to_string(),
+        }
+    }
+}
+
+type PResult<T> = Result<T, ParseError>;
diff --git a/compiler/rustc_mir_build/src/build/custom/parse.rs b/compiler/rustc_mir_build/src/build/custom/parse.rs
new file mode 100644
index 000000000000..52cb0a4826d0
--- /dev/null
+++ b/compiler/rustc_mir_build/src/build/custom/parse.rs
@@ -0,0 +1,245 @@
+use rustc_index::vec::IndexVec;
+use rustc_middle::{mir::*, thir::*, ty::Ty};
+use rustc_span::Span;
+
+use super::{PResult, ParseCtxt, ParseError};
+
+mod instruction;
+
+/// Helper macro for parsing custom MIR.
+///
+/// Example usage looks something like:
+/// ```rust,ignore (incomplete example)
+/// parse_by_kind!(
+///     self, // : &ParseCtxt
+///     expr_id, // what you're matching against
+///     "assignment", // the thing you're trying to parse
+///     @call("mir_assign", args) => { args[0] }, // match invocations of the `mir_assign` special function
+///     ExprKind::Assign { lhs, .. } => { lhs }, // match thir assignment expressions
+///     // no need for fallthrough case - reasonable error is automatically generated
+/// )
+/// ```
+macro_rules! parse_by_kind {
+    (
+        $self:ident,
+        $expr_id:expr,
+        $expected:literal,
+        $(
+            @call($name:literal, $args:ident) => $call_expr:expr,
+        )*
+        $(
+            $pat:pat => $expr:expr,
+        )*
+    ) => {{
+        let expr_id = $self.preparse($expr_id);
+        let expr = &$self.thir[expr_id];
+        match &expr.kind {
+            $(
+                ExprKind::Call { ty, fun: _, args: $args, .. } if {
+                    match ty.kind() {
+                        ty::FnDef(did, _) => {
+                            $self.tcx.is_diagnostic_item(rustc_span::Symbol::intern($name), *did)
+                        }
+                        _ => false,
+                    }
+                } => $call_expr,
+            )*
+            $(
+                $pat => $expr,
+            )*
+            #[allow(unreachable_patterns)]
+            _ => return Err($self.expr_error(expr_id, $expected))
+        }
+    }};
+}
+pub(crate) use parse_by_kind;
+
+impl<'tcx, 'body> ParseCtxt<'tcx, 'body> {
+    /// Expressions should only ever be matched on after preparsing them. This removes extra scopes
+    /// we don't care about.
+    fn preparse(&self, expr_id: ExprId) -> ExprId {
+        let expr = &self.thir[expr_id];
+        match expr.kind {
+            ExprKind::Scope { value, .. } => self.preparse(value),
+            _ => expr_id,
+        }
+    }
+
+    fn statement_as_expr(&self, stmt_id: StmtId) -> PResult<ExprId> {
+        match &self.thir[stmt_id].kind {
+            StmtKind::Expr { expr, .. } => Ok(*expr),
+            kind @ StmtKind::Let { pattern, .. } => {
+                return Err(ParseError {
+                    span: pattern.span,
+                    item_description: format!("{:?}", kind),
+                    expected: "expression".to_string(),
+                });
+            }
+        }
+    }
+
+    pub fn parse_args(&mut self, params: &IndexVec<ParamId, Param<'tcx>>) -> PResult<()> {
+        for param in params.iter() {
+            let (var, span) = {
+                let pat = param.pat.as_ref().unwrap();
+                match &pat.kind {
+                    PatKind::Binding { var, .. } => (*var, pat.span),
+                    _ => {
+                        return Err(ParseError {
+                            span: pat.span,
+                            item_description: format!("{:?}", pat.kind),
+                            expected: "local".to_string(),
+                        });
+                    }
+                }
+            };
+            let decl = LocalDecl::new(param.ty, span);
+            let local = self.body.local_decls.push(decl);
+            self.local_map.insert(var, local);
+        }
+
+        Ok(())
+    }
+
+    /// Bodies are of the form:
+    ///
+    /// ```text
+    /// {
+    ///     let bb1: BasicBlock;
+    ///     let bb2: BasicBlock;
+    ///     {
+    ///         let RET: _;
+    ///         let local1;
+    ///         let local2;
+    ///
+    ///         {
+    ///             { // entry block
+    ///                 statement1;
+    ///                 terminator1
+    ///             };
+    ///
+    ///             bb1 = {
+    ///                 statement2;
+    ///                 terminator2
+    ///             };
+    ///
+    ///             bb2 = {
+    ///                 statement3;
+    ///                 terminator3
+    ///             }
+    ///
+    ///             RET
+    ///         }
+    ///     }
+    /// }
+    /// ```
+    ///
+    /// This allows us to easily parse the basic blocks declarations, local declarations, and
+    /// basic block definitions in order.
+    pub fn parse_body(&mut self, expr_id: ExprId) -> PResult<()> {
+        let body = parse_by_kind!(self, expr_id, "whole body",
+            ExprKind::Block { block } => self.thir[*block].expr.unwrap(),
+        );
+        let (block_decls, rest) = parse_by_kind!(self, body, "body with block decls",
+            ExprKind::Block { block } => {
+                let block = &self.thir[*block];
+                (&block.stmts, block.expr.unwrap())
+            },
+        );
+        self.parse_block_decls(block_decls.iter().copied())?;
+
+        let (local_decls, rest) = parse_by_kind!(self, rest, "body with local decls",
+            ExprKind::Block { block } => {
+                let block = &self.thir[*block];
+                (&block.stmts, block.expr.unwrap())
+            },
+        );
+        self.parse_local_decls(local_decls.iter().copied())?;
+
+        let block_defs = parse_by_kind!(self, rest, "body with block defs",
+            ExprKind::Block { block } => &self.thir[*block].stmts,
+        );
+        for (i, block_def) in block_defs.iter().enumerate() {
+            let block = self.parse_block_def(self.statement_as_expr(*block_def)?)?;
+            self.body.basic_blocks_mut()[BasicBlock::from_usize(i)] = block;
+        }
+
+        Ok(())
+    }
+
+    fn parse_block_decls(&mut self, stmts: impl Iterator<Item = StmtId>) -> PResult<()> {
+        for stmt in stmts {
+            let (var, _, _) = self.parse_let_statement(stmt)?;
+            let data = BasicBlockData::new(None);
+            let block = self.body.basic_blocks_mut().push(data);
+            self.block_map.insert(var, block);
+        }
+
+        Ok(())
+    }
+
+    fn parse_local_decls(&mut self, mut stmts: impl Iterator<Item = StmtId>) -> PResult<()> {
+        let (ret_var, ..) = self.parse_let_statement(stmts.next().unwrap())?;
+        self.local_map.insert(ret_var, Local::from_u32(0));
+
+        for stmt in stmts {
+            let (var, ty, span) = self.parse_let_statement(stmt)?;
+            let decl = LocalDecl::new(ty, span);
+            let local = self.body.local_decls.push(decl);
+            self.local_map.insert(var, local);
+        }
+
+        Ok(())
+    }
+
+    fn parse_let_statement(&mut self, stmt_id: StmtId) -> PResult<(LocalVarId, Ty<'tcx>, Span)> {
+        let pattern = match &self.thir[stmt_id].kind {
+            StmtKind::Let { pattern, .. } => pattern,
+            StmtKind::Expr { expr, .. } => {
+                return Err(self.expr_error(*expr, "let statement"));
+            }
+        };
+
+        self.parse_var(pattern)
+    }
+
+    fn parse_var(&mut self, mut pat: &Pat<'tcx>) -> PResult<(LocalVarId, Ty<'tcx>, Span)> {
+        // Make sure we throw out any `AscribeUserType` we find
+        loop {
+            match &pat.kind {
+                PatKind::Binding { var, ty, .. } => break Ok((*var, *ty, pat.span)),
+                PatKind::AscribeUserType { subpattern, .. } => {
+                    pat = subpattern;
+                }
+                _ => {
+                    break Err(ParseError {
+                        span: pat.span,
+                        item_description: format!("{:?}", pat.kind),
+                        expected: "local".to_string(),
+                    });
+                }
+            }
+        }
+    }
+
+    fn parse_block_def(&self, expr_id: ExprId) -> PResult<BasicBlockData<'tcx>> {
+        let block = parse_by_kind!(self, expr_id, "basic block",
+            ExprKind::Block { block } => &self.thir[*block],
+        );
+
+        let mut data = BasicBlockData::new(None);
+        for stmt_id in &*block.stmts {
+            let stmt = self.statement_as_expr(*stmt_id)?;
+            let statement = self.parse_statement(stmt)?;
+            data.statements.push(Statement { source_info: self.source_info, kind: statement });
+        }
+
+        let Some(trailing) = block.expr else {
+            return Err(self.expr_error(expr_id, "terminator"))
+        };
+        let terminator = self.parse_terminator(trailing)?;
+        data.terminator = Some(Terminator { source_info: self.source_info, kind: terminator });
+
+        Ok(data)
+    }
+}
diff --git a/compiler/rustc_mir_build/src/build/custom/parse/instruction.rs b/compiler/rustc_mir_build/src/build/custom/parse/instruction.rs
new file mode 100644
index 000000000000..6d6176584f5f
--- /dev/null
+++ b/compiler/rustc_mir_build/src/build/custom/parse/instruction.rs
@@ -0,0 +1,72 @@
+use rustc_middle::{mir::*, thir::*, ty};
+
+use super::{parse_by_kind, PResult, ParseCtxt};
+
+impl<'tcx, 'body> ParseCtxt<'tcx, 'body> {
+    pub fn parse_statement(&self, expr_id: ExprId) -> PResult<StatementKind<'tcx>> {
+        parse_by_kind!(self, expr_id, "statement",
+            @call("mir_retag", args) => {
+                Ok(StatementKind::Retag(RetagKind::Default, Box::new(self.parse_place(args[0])?)))
+            },
+            @call("mir_retag_raw", args) => {
+                Ok(StatementKind::Retag(RetagKind::Raw, Box::new(self.parse_place(args[0])?)))
+            },
+            ExprKind::Assign { lhs, rhs } => {
+                let lhs = self.parse_place(*lhs)?;
+                let rhs = self.parse_rvalue(*rhs)?;
+                Ok(StatementKind::Assign(Box::new((lhs, rhs))))
+            },
+        )
+    }
+
+    pub fn parse_terminator(&self, expr_id: ExprId) -> PResult<TerminatorKind<'tcx>> {
+        parse_by_kind!(self, expr_id, "terminator",
+            @call("mir_return", _args) => {
+                Ok(TerminatorKind::Return)
+            },
+            @call("mir_goto", args) => {
+                Ok(TerminatorKind::Goto { target: self.parse_block(args[0])? } )
+            },
+        )
+    }
+
+    fn parse_rvalue(&self, expr_id: ExprId) -> PResult<Rvalue<'tcx>> {
+        parse_by_kind!(self, expr_id, "rvalue",
+            ExprKind::Borrow { borrow_kind, arg } => Ok(
+                Rvalue::Ref(self.tcx.lifetimes.re_erased, *borrow_kind, self.parse_place(*arg)?)
+            ),
+            ExprKind::AddressOf { mutability, arg } => Ok(
+                Rvalue::AddressOf(*mutability, self.parse_place(*arg)?)
+            ),
+            _ => self.parse_operand(expr_id).map(Rvalue::Use),
+        )
+    }
+
+    fn parse_operand(&self, expr_id: ExprId) -> PResult<Operand<'tcx>> {
+        parse_by_kind!(self, expr_id, "operand",
+            @call("mir_move", args) => self.parse_place(args[0]).map(Operand::Move),
+            _ => self.parse_place(expr_id).map(Operand::Copy),
+        )
+    }
+
+    fn parse_place(&self, expr_id: ExprId) -> PResult<Place<'tcx>> {
+        parse_by_kind!(self, expr_id, "place",
+            ExprKind::Deref { arg } => Ok(
+                self.parse_place(*arg)?.project_deeper(&[PlaceElem::Deref], self.tcx)
+            ),
+            _ => self.parse_local(expr_id).map(Place::from),
+        )
+    }
+
+    fn parse_local(&self, expr_id: ExprId) -> PResult<Local> {
+        parse_by_kind!(self, expr_id, "local",
+            ExprKind::VarRef { id } => Ok(self.local_map[id]),
+        )
+    }
+
+    fn parse_block(&self, expr_id: ExprId) -> PResult<BasicBlock> {
+        parse_by_kind!(self, expr_id, "basic block",
+            ExprKind::VarRef { id } => Ok(self.block_map[id]),
+        )
+    }
+}
diff --git a/compiler/rustc_mir_build/src/build/expr/as_constant.rs b/compiler/rustc_mir_build/src/build/expr/as_constant.rs
index 37dc1ad9f0d4..7d8a940bde5c 100644
--- a/compiler/rustc_mir_build/src/build/expr/as_constant.rs
+++ b/compiler/rustc_mir_build/src/build/expr/as_constant.rs
@@ -9,6 +9,7 @@ use rustc_middle::mir::interpret::{
 use rustc_middle::mir::*;
 use rustc_middle::thir::*;
 use rustc_middle::ty::{self, CanonicalUserTypeAnnotation, TyCtxt};
+use rustc_span::DUMMY_SP;
 use rustc_target::abi::Size;
 
 impl<'a, 'tcx> Builder<'a, 'tcx> {
@@ -26,7 +27,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                 let literal =
                     match lit_to_mir_constant(tcx, LitToConstInput { lit: &lit.node, ty, neg }) {
                         Ok(c) => c,
-                        Err(LitToConstError::Reported) => ConstantKind::Ty(tcx.const_error(ty)),
+                        Err(LitToConstError::Reported(guar)) => {
+                            ConstantKind::Ty(tcx.const_error_with_guaranteed(ty, guar))
+                        }
                         Err(LitToConstError::TypeError) => {
                             bug!("encountered type error in `lit_to_mir_constant")
                         }
@@ -74,8 +77,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                 Constant { user_ty, span, literal }
             }
             ExprKind::ConstParam { param, def_id: _ } => {
-                let const_param =
-                    tcx.mk_const(ty::ConstS { kind: ty::ConstKind::Param(param), ty: expr.ty });
+                let const_param = tcx.mk_const(ty::ConstKind::Param(param), expr.ty);
                 let literal = ConstantKind::Ty(const_param);
 
                 Constant { user_ty: None, span, literal }
@@ -106,7 +108,15 @@ pub(crate) fn lit_to_mir_constant<'tcx>(
     let LitToConstInput { lit, ty, neg } = lit_input;
     let trunc = |n| {
         let param_ty = ty::ParamEnv::reveal_all().and(ty);
-        let width = tcx.layout_of(param_ty).map_err(|_| LitToConstError::Reported)?.size;
+        let width = tcx
+            .layout_of(param_ty)
+            .map_err(|_| {
+                LitToConstError::Reported(tcx.sess.delay_span_bug(
+                    DUMMY_SP,
+                    format!("couldn't compute width of literal: {:?}", lit_input.lit),
+                ))
+            })?
+            .size;
         trace!("trunc {} with size {} and shift {}", n, width.bits(), 128 - width.bits());
         let result = width.truncate(n);
         trace!("trunc result: {}", result);
@@ -137,12 +147,20 @@ pub(crate) fn lit_to_mir_constant<'tcx>(
         (ast::LitKind::Int(n, _), ty::Uint(_)) | (ast::LitKind::Int(n, _), ty::Int(_)) => {
             trunc(if neg { (*n as i128).overflowing_neg().0 as u128 } else { *n })?
         }
-        (ast::LitKind::Float(n, _), ty::Float(fty)) => {
-            parse_float_into_constval(*n, *fty, neg).ok_or(LitToConstError::Reported)?
-        }
+        (ast::LitKind::Float(n, _), ty::Float(fty)) => parse_float_into_constval(*n, *fty, neg)
+            .ok_or_else(|| {
+                LitToConstError::Reported(tcx.sess.delay_span_bug(
+                    DUMMY_SP,
+                    format!("couldn't parse float literal: {:?}", lit_input.lit),
+                ))
+            })?,
         (ast::LitKind::Bool(b), ty::Bool) => ConstValue::Scalar(Scalar::from_bool(*b)),
         (ast::LitKind::Char(c), ty::Char) => ConstValue::Scalar(Scalar::from_char(*c)),
-        (ast::LitKind::Err, _) => return Err(LitToConstError::Reported),
+        (ast::LitKind::Err, _) => {
+            return Err(LitToConstError::Reported(
+                tcx.sess.delay_span_bug(DUMMY_SP, "encountered LitKind::Err during mir build"),
+            ));
+        }
         _ => return Err(LitToConstError::TypeError),
     };
 
diff --git a/compiler/rustc_mir_build/src/build/expr/as_operand.rs b/compiler/rustc_mir_build/src/build/expr/as_operand.rs
index e707c373f0dd..c8610af7038d 100644
--- a/compiler/rustc_mir_build/src/build/expr/as_operand.rs
+++ b/compiler/rustc_mir_build/src/build/expr/as_operand.rs
@@ -153,12 +153,11 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
 
         if tcx.features().unsized_fn_params {
             let ty = expr.ty;
-            let span = expr.span;
             let param_env = this.param_env;
 
-            if !ty.is_sized(tcx.at(span), param_env) {
+            if !ty.is_sized(tcx, param_env) {
                 // !sized means !copy, so this is an unsized move
-                assert!(!ty.is_copy_modulo_regions(tcx.at(span), param_env));
+                assert!(!ty.is_copy_modulo_regions(tcx, param_env));
 
                 // As described above, detect the case where we are passing a value of unsized
                 // type, and that value is coming from the deref of a box.
diff --git a/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs b/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs
index 3dafdcb78871..5c82fb1ddc0d 100644
--- a/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs
+++ b/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs
@@ -2,6 +2,7 @@
 
 use rustc_index::vec::Idx;
 use rustc_middle::ty::util::IntTypeExt;
+use rustc_target::abi::{Abi, Primitive};
 
 use crate::build::expr::as_place::PlaceBase;
 use crate::build::expr::category::{Category, RvalueFunc};
@@ -198,6 +199,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                 let (source, ty) = if let ty::Adt(adt_def, ..) = source.ty.kind() && adt_def.is_enum() {
                     let discr_ty = adt_def.repr().discr_type().to_ty(this.tcx);
                     let temp = unpack!(block = this.as_temp(block, scope, source, Mutability::Not));
+                    let layout = this.tcx.layout_of(this.param_env.and(source.ty));
                     let discr = this.temp(discr_ty, source.span);
                     this.cfg.push_assign(
                         block,
@@ -205,8 +207,55 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                         discr,
                         Rvalue::Discriminant(temp.into()),
                     );
+                    let (op,ty) = (Operand::Move(discr), discr_ty);
+
+                    if let Abi::Scalar(scalar) = layout.unwrap().abi{
+                        if let Primitive::Int(_, signed) = scalar.primitive() {
+                            let range = scalar.valid_range(&this.tcx);
+                            // FIXME: Handle wraparound cases too.
+                            if range.end >= range.start {
+                                let mut assumer = |range: u128, bin_op: BinOp| {
+                                    // We will be overwriting this val if our scalar is signed value
+                                    // because sign extension on unsigned types might cause unintended things
+                                    let mut range_val =
+                                        ConstantKind::from_bits(this.tcx, range, ty::ParamEnv::empty().and(discr_ty));
+                                    let bool_ty = this.tcx.types.bool;
+                                    if signed {
+                                        let scalar_size_extend = scalar.size(&this.tcx).sign_extend(range);
+                                        let discr_layout = this.tcx.layout_of(this.param_env.and(discr_ty));
+                                        let truncated_val = discr_layout.unwrap().size.truncate(scalar_size_extend);
+                                        range_val = ConstantKind::from_bits(
+                                            this.tcx,
+                                            truncated_val,
+                                            ty::ParamEnv::empty().and(discr_ty),
+                                        );
+                                    }
+                                    let lit_op = this.literal_operand(expr.span, range_val);
+                                    let is_bin_op = this.temp(bool_ty, expr_span);
+                                    this.cfg.push_assign(
+                                        block,
+                                        source_info,
+                                        is_bin_op,
+                                        Rvalue::BinaryOp(bin_op, Box::new(((lit_op), (Operand::Copy(discr))))),
+                                    );
+                                    this.cfg.push(
+                                        block,
+                                        Statement {
+                                            source_info,
+                                            kind: StatementKind::Intrinsic(Box::new(NonDivergingIntrinsic::Assume(
+                                                Operand::Copy(is_bin_op),
+                                            ))),
+                                        },
+                                    )
+                                };
+                                assumer(range.end, BinOp::Ge);
+                                assumer(range.start, BinOp::Le);
+                            }
+                        }
+                    }
+
+                    (op,ty)
 
-                    (Operand::Move(discr), discr_ty)
                 } else {
                     let ty = source.ty;
                     let source = unpack!(
diff --git a/compiler/rustc_mir_build/src/build/matches/mod.rs b/compiler/rustc_mir_build/src/build/matches/mod.rs
index 3f813e0af0da..dfd8649cb97e 100644
--- a/compiler/rustc_mir_build/src/build/matches/mod.rs
+++ b/compiler/rustc_mir_build/src/build/matches/mod.rs
@@ -364,12 +364,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                     let arm_block = this.bind_pattern(
                         outer_source_info,
                         candidate,
-                        arm.guard.as_ref(),
                         &fake_borrow_temps,
                         scrutinee_span,
-                        Some(arm.span),
-                        Some(arm.scope),
-                        Some(match_scope),
+                        Some((arm, match_scope)),
                         false,
                     );
 
@@ -410,12 +407,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
         &mut self,
         outer_source_info: SourceInfo,
         candidate: Candidate<'_, 'tcx>,
-        guard: Option<&Guard<'tcx>>,
         fake_borrow_temps: &[(Place<'tcx>, Local)],
         scrutinee_span: Span,
-        arm_span: Option<Span>,
-        arm_scope: Option<region::Scope>,
-        match_scope: Option<region::Scope>,
+        arm_match_scope: Option<(&Arm<'tcx>, region::Scope)>,
         storages_alive: bool,
     ) -> BasicBlock {
         if candidate.subcandidates.is_empty() {
@@ -424,11 +418,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
             self.bind_and_guard_matched_candidate(
                 candidate,
                 &[],
-                guard,
                 fake_borrow_temps,
                 scrutinee_span,
-                arm_span,
-                match_scope,
+                arm_match_scope,
                 true,
                 storages_alive,
             )
@@ -449,6 +441,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
             // we lower the guard.
             let target_block = self.cfg.start_new_block();
             let mut schedule_drops = true;
+            let arm = arm_match_scope.unzip().0;
             // We keep a stack of all of the bindings and type ascriptions
             // from the parent candidates that we visit, that also need to
             // be bound for each candidate.
@@ -456,21 +449,19 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                 candidate,
                 &mut Vec::new(),
                 &mut |leaf_candidate, parent_bindings| {
-                    if let Some(arm_scope) = arm_scope {
-                        self.clear_top_scope(arm_scope);
+                    if let Some(arm) = arm {
+                        self.clear_top_scope(arm.scope);
                     }
                     let binding_end = self.bind_and_guard_matched_candidate(
                         leaf_candidate,
                         parent_bindings,
-                        guard,
                         &fake_borrow_temps,
                         scrutinee_span,
-                        arm_span,
-                        match_scope,
+                        arm_match_scope,
                         schedule_drops,
                         storages_alive,
                     );
-                    if arm_scope.is_none() {
+                    if arm.is_none() {
                         schedule_drops = false;
                     }
                     self.cfg.goto(binding_end, outer_source_info, target_block);
@@ -636,12 +627,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
         self.bind_pattern(
             self.source_info(irrefutable_pat.span),
             candidate,
-            None,
             &fake_borrow_temps,
             irrefutable_pat.span,
             None,
-            None,
-            None,
             false,
         )
         .unit()
@@ -1820,12 +1808,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
         let post_guard_block = self.bind_pattern(
             self.source_info(pat.span),
             guard_candidate,
-            None,
             &fake_borrow_temps,
             expr.span,
             None,
-            None,
-            None,
             false,
         );
 
@@ -1844,11 +1829,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
         &mut self,
         candidate: Candidate<'pat, 'tcx>,
         parent_bindings: &[(Vec<Binding<'tcx>>, Vec<Ascription<'tcx>>)],
-        guard: Option<&Guard<'tcx>>,
         fake_borrows: &[(Place<'tcx>, Local)],
         scrutinee_span: Span,
-        arm_span: Option<Span>,
-        match_scope: Option<region::Scope>,
+        arm_match_scope: Option<(&Arm<'tcx>, region::Scope)>,
         schedule_drops: bool,
         storages_alive: bool,
     ) -> BasicBlock {
@@ -1960,7 +1943,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
         //      the reference that we create for the arm.
         //    * So we eagerly create the reference for the arm and then take a
         //      reference to that.
-        if let Some(guard) = guard {
+        if let Some((arm, match_scope)) = arm_match_scope
+            && let Some(guard) = &arm.guard
+        {
             let tcx = self.tcx;
             let bindings = parent_bindings
                 .iter()
@@ -1981,8 +1966,6 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                 self.cfg.push_assign(block, scrutinee_source_info, Place::from(temp), borrow);
             }
 
-            let arm_span = arm_span.unwrap();
-            let match_scope = match_scope.unwrap();
             let mut guard_span = rustc_span::DUMMY_SP;
 
             let (post_guard_block, otherwise_post_guard_block) =
@@ -1995,13 +1978,13 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                             e,
                             None,
                             match_scope,
-                            this.source_info(arm_span),
+                            this.source_info(arm.span),
                         )
                     }
                     Guard::IfLet(ref pat, scrutinee) => {
                         let s = &this.thir[scrutinee];
                         guard_span = s.span;
-                        this.lower_let_expr(block, s, pat, match_scope, None, arm_span)
+                        this.lower_let_expr(block, s, pat, match_scope, None, arm.span)
                     }
                 });
 
@@ -2317,24 +2300,18 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
             let matching = this.bind_pattern(
                 this.source_info(pattern.span),
                 candidate,
-                None,
                 &fake_borrow_temps,
                 initializer_span,
                 None,
-                None,
-                None,
                 true,
             );
             // This block is for the failure case
             let failure = this.bind_pattern(
                 this.source_info(else_block_span),
                 wildcard,
-                None,
                 &fake_borrow_temps,
                 initializer_span,
                 None,
-                None,
-                None,
                 true,
             );
             this.break_for_else(failure, *let_else_scope, this.source_info(initializer_span));
diff --git a/compiler/rustc_mir_build/src/build/mod.rs b/compiler/rustc_mir_build/src/build/mod.rs
index cbcf9cd129f3..437ac8d82a1a 100644
--- a/compiler/rustc_mir_build/src/build/mod.rs
+++ b/compiler/rustc_mir_build/src/build/mod.rs
@@ -481,6 +481,22 @@ fn construct_fn<'tcx>(
         (None, fn_sig.output())
     };
 
+    if let Some(custom_mir_attr) =
+        tcx.hir().attrs(fn_id).iter().find(|attr| attr.name_or_empty() == sym::custom_mir)
+    {
+        return custom::build_custom_mir(
+            tcx,
+            fn_def.did.to_def_id(),
+            thir,
+            expr,
+            arguments,
+            return_ty,
+            return_ty_span,
+            span,
+            custom_mir_attr,
+        );
+    }
+
     let infcx = tcx.infer_ctxt().build();
     let mut builder = Builder::new(
         thir,
@@ -1033,6 +1049,7 @@ pub(crate) fn parse_float_into_scalar(
 
 mod block;
 mod cfg;
+mod custom;
 mod expr;
 mod matches;
 mod misc;
diff --git a/compiler/rustc_mir_build/src/check_unsafety.rs b/compiler/rustc_mir_build/src/check_unsafety.rs
index 5e8ce65daf0f..fb1ea9ed300a 100644
--- a/compiler/rustc_mir_build/src/check_unsafety.rs
+++ b/compiler/rustc_mir_build/src/check_unsafety.rs
@@ -260,7 +260,7 @@ impl<'a, 'tcx> Visitor<'a, 'tcx> for UnsafetyVisitor<'a, 'tcx> {
                     };
                     match borrow_kind {
                         BorrowKind::Shallow | BorrowKind::Shared | BorrowKind::Unique => {
-                            if !ty.is_freeze(self.tcx.at(pat.span), self.param_env) {
+                            if !ty.is_freeze(self.tcx, self.param_env) {
                                 self.requires_unsafe(pat.span, BorrowOfLayoutConstrainedField);
                             }
                         }
@@ -457,9 +457,7 @@ impl<'a, 'tcx> Visitor<'a, 'tcx> for UnsafetyVisitor<'a, 'tcx> {
                 if visitor.found {
                     match borrow_kind {
                         BorrowKind::Shallow | BorrowKind::Shared | BorrowKind::Unique
-                            if !self.thir[arg]
-                                .ty
-                                .is_freeze(self.tcx.at(self.thir[arg].span), self.param_env) =>
+                            if !self.thir[arg].ty.is_freeze(self.tcx, self.param_env) =>
                         {
                             self.requires_unsafe(expr.span, BorrowOfLayoutConstrainedField)
                         }
diff --git a/compiler/rustc_mir_build/src/thir/constant.rs b/compiler/rustc_mir_build/src/thir/constant.rs
index f626571b5b2c..85e8801bda3e 100644
--- a/compiler/rustc_mir_build/src/thir/constant.rs
+++ b/compiler/rustc_mir_build/src/thir/constant.rs
@@ -1,6 +1,7 @@
 use rustc_ast as ast;
 use rustc_middle::mir::interpret::{LitToConstError, LitToConstInput};
 use rustc_middle::ty::{self, ParamEnv, ScalarInt, TyCtxt};
+use rustc_span::DUMMY_SP;
 
 pub(crate) fn lit_to_const<'tcx>(
     tcx: TyCtxt<'tcx>,
@@ -10,7 +11,15 @@ pub(crate) fn lit_to_const<'tcx>(
 
     let trunc = |n| {
         let param_ty = ParamEnv::reveal_all().and(ty);
-        let width = tcx.layout_of(param_ty).map_err(|_| LitToConstError::Reported)?.size;
+        let width = tcx
+            .layout_of(param_ty)
+            .map_err(|_| {
+                LitToConstError::Reported(tcx.sess.delay_span_bug(
+                    DUMMY_SP,
+                    format!("couldn't compute width of literal: {:?}", lit_input.lit),
+                ))
+            })?
+            .size;
         trace!("trunc {} with size {} and shift {}", n, width.bits(), 128 - width.bits());
         let result = width.truncate(n);
         trace!("trunc result: {}", result);
@@ -44,7 +53,11 @@ pub(crate) fn lit_to_const<'tcx>(
         }
         (ast::LitKind::Bool(b), ty::Bool) => ty::ValTree::from_scalar_int((*b).into()),
         (ast::LitKind::Char(c), ty::Char) => ty::ValTree::from_scalar_int((*c).into()),
-        (ast::LitKind::Err, _) => return Err(LitToConstError::Reported),
+        (ast::LitKind::Err, _) => {
+            return Err(LitToConstError::Reported(
+                tcx.sess.delay_span_bug(DUMMY_SP, "encountered LitKind::Err during mir build"),
+            ));
+        }
         _ => return Err(LitToConstError::TypeError),
     };
 
diff --git a/compiler/rustc_mir_build/src/thir/cx/expr.rs b/compiler/rustc_mir_build/src/thir/cx/expr.rs
index c7a7c3e3fa8e..c4639d3a513d 100644
--- a/compiler/rustc_mir_build/src/thir/cx/expr.rs
+++ b/compiler/rustc_mir_build/src/thir/cx/expr.rs
@@ -51,11 +51,17 @@ impl<'tcx> Cx<'tcx> {
         trace!(?expr.ty);
 
         // Now apply adjustments, if any.
-        for adjustment in self.typeck_results.expr_adjustments(hir_expr) {
-            trace!(?expr, ?adjustment);
-            let span = expr.span;
-            expr =
-                self.apply_adjustment(hir_expr, expr, adjustment, adjustment_span.unwrap_or(span));
+        if self.apply_adjustments {
+            for adjustment in self.typeck_results.expr_adjustments(hir_expr) {
+                trace!(?expr, ?adjustment);
+                let span = expr.span;
+                expr = self.apply_adjustment(
+                    hir_expr,
+                    expr,
+                    adjustment,
+                    adjustment_span.unwrap_or(span),
+                );
+            }
         }
 
         trace!(?expr.ty, "after adjustments");
diff --git a/compiler/rustc_mir_build/src/thir/cx/mod.rs b/compiler/rustc_mir_build/src/thir/cx/mod.rs
index 1d95d6b53fbe..b5c4b7b137d4 100644
--- a/compiler/rustc_mir_build/src/thir/cx/mod.rs
+++ b/compiler/rustc_mir_build/src/thir/cx/mod.rs
@@ -80,6 +80,9 @@ struct Cx<'tcx> {
     /// for the receiver.
     adjustment_span: Option<(HirId, Span)>,
 
+    /// False to indicate that adjustments should not be applied. Only used for `custom_mir`
+    apply_adjustments: bool,
+
     /// The `DefId` of the owner of this body.
     body_owner: DefId,
 }
@@ -87,6 +90,8 @@ struct Cx<'tcx> {
 impl<'tcx> Cx<'tcx> {
     fn new(tcx: TyCtxt<'tcx>, def: ty::WithOptConstParam<LocalDefId>) -> Cx<'tcx> {
         let typeck_results = tcx.typeck_opt_const_arg(def);
+        let did = def.did;
+        let hir = tcx.hir();
         Cx {
             tcx,
             thir: Thir::new(),
@@ -94,8 +99,12 @@ impl<'tcx> Cx<'tcx> {
             region_scope_tree: tcx.region_scope_tree(def.did),
             typeck_results,
             rvalue_scopes: &typeck_results.rvalue_scopes,
-            body_owner: def.did.to_def_id(),
+            body_owner: did.to_def_id(),
             adjustment_span: None,
+            apply_adjustments: hir
+                .attrs(hir.local_def_id_to_hir_id(did))
+                .iter()
+                .all(|attr| attr.name_or_empty() != rustc_span::sym::custom_mir),
         }
     }
 
diff --git a/compiler/rustc_mir_build/src/thir/pattern/check_match.rs b/compiler/rustc_mir_build/src/thir/pattern/check_match.rs
index 5984c800d838..93a3dd8962a9 100644
--- a/compiler/rustc_mir_build/src/thir/pattern/check_match.rs
+++ b/compiler/rustc_mir_build/src/thir/pattern/check_match.rs
@@ -79,7 +79,10 @@ impl<'tcx> Visitor<'tcx> for MatchVisitor<'_, '_, 'tcx> {
         intravisit::walk_local(self, loc);
         let els = loc.els;
         if let Some(init) = loc.init && els.is_some() {
-            self.check_let(&loc.pat, init, loc.span);
+            // Build a span without the else { ... } as we don't want to underline
+            // the entire else block in the IDE setting.
+            let span = loc.span.with_hi(init.span.hi());
+            self.check_let(&loc.pat, init, span);
         }
 
         let (msg, sp) = match loc.source {
@@ -507,7 +510,7 @@ impl<'p, 'tcx> MatchVisitor<'_, 'p, 'tcx> {
                                 _ => "aren't",
                             },
                         ),
-                        " else { todo!() }".to_string(),
+                        " else { todo!() }",
                         Applicability::HasPlaceholders,
                     );
                 }
@@ -630,11 +633,6 @@ fn irrefutable_let_patterns(
     count: usize,
     span: Span,
 ) {
-    let span = match source {
-        LetSource::LetElse(span) => span,
-        _ => span,
-    };
-
     macro_rules! emit_diag {
         (
             $lint:expr,
@@ -680,7 +678,7 @@ fn irrefutable_let_patterns(
                 "removing the guard and adding a `let` inside the match arm"
             );
         }
-        LetSource::LetElse(..) => {
+        LetSource::LetElse => {
             emit_diag!(
                 lint,
                 "`let...else`",
@@ -1004,8 +1002,8 @@ fn maybe_point_at_variant<'a, 'p: 'a, 'tcx: 'a>(
 }
 
 /// Check if a by-value binding is by-value. That is, check if the binding's type is not `Copy`.
-fn is_binding_by_move(cx: &MatchVisitor<'_, '_, '_>, hir_id: HirId, span: Span) -> bool {
-    !cx.typeck_results.node_type(hir_id).is_copy_modulo_regions(cx.tcx.at(span), cx.param_env)
+fn is_binding_by_move(cx: &MatchVisitor<'_, '_, '_>, hir_id: HirId) -> bool {
+    !cx.typeck_results.node_type(hir_id).is_copy_modulo_regions(cx.tcx, cx.param_env)
 }
 
 /// Check that there are no borrow or move conflicts in `binding @ subpat` patterns.
@@ -1031,7 +1029,7 @@ fn check_borrow_conflicts_in_at_patterns(cx: &MatchVisitor<'_, '_, '_>, pat: &Pa
 
     // Get the binding move, extract the mutability if by-ref.
     let mut_outer = match typeck_results.extract_binding_mode(sess, pat.hir_id, pat.span) {
-        Some(ty::BindByValue(_)) if is_binding_by_move(cx, pat.hir_id, pat.span) => {
+        Some(ty::BindByValue(_)) if is_binding_by_move(cx, pat.hir_id) => {
             // We have `x @ pat` where `x` is by-move. Reject all borrows in `pat`.
             let mut conflicts_ref = Vec::new();
             sub.each_binding(|_, hir_id, span, _| {
@@ -1070,7 +1068,7 @@ fn check_borrow_conflicts_in_at_patterns(cx: &MatchVisitor<'_, '_, '_>, pat: &Pa
                 (Mutability::Mut, Mutability::Mut) => conflicts_mut_mut.push((span, name)), // 2x `ref mut`.
                 _ => conflicts_mut_ref.push((span, name)), // `ref` + `ref mut` in either direction.
             },
-            Some(ty::BindByValue(_)) if is_binding_by_move(cx, hir_id, span) => {
+            Some(ty::BindByValue(_)) if is_binding_by_move(cx, hir_id) => {
                 conflicts_move.push((span, name)) // `ref mut?` + by-move conflict.
             }
             Some(ty::BindByValue(_)) | None => {} // `ref mut?` + by-copy is fine.
@@ -1127,7 +1125,7 @@ pub enum LetSource {
     GenericLet,
     IfLet,
     IfLetGuard,
-    LetElse(Span),
+    LetElse,
     WhileLet,
 }
 
@@ -1156,8 +1154,8 @@ fn let_source_parent(tcx: TyCtxt<'_>, parent: HirId, pat_id: Option<HirId>) -> L
     let parent_parent = hir.get_parent_node(parent);
     let parent_parent_node = hir.get(parent_parent);
     match parent_parent_node {
-        hir::Node::Stmt(hir::Stmt { kind: hir::StmtKind::Local(_), span, .. }) => {
-            return LetSource::LetElse(*span);
+        hir::Node::Stmt(hir::Stmt { kind: hir::StmtKind::Local(_), .. }) => {
+            return LetSource::LetElse;
         }
         hir::Node::Arm(hir::Arm { guard: Some(hir::Guard::If(_)), .. }) => {
             return LetSource::IfLetGuard;
diff --git a/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs b/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs
index cf8ae776be96..ad12e0116211 100644
--- a/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs
+++ b/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs
@@ -506,7 +506,7 @@ impl<'tcx> ConstToPat<'tcx> {
                 // convert the dereferenced constant to a pattern that is the sub-pattern of the
                 // deref pattern.
                 _ => {
-                    if !pointee_ty.is_sized(tcx.at(span), param_env) {
+                    if !pointee_ty.is_sized(tcx, param_env) {
                         // `tcx.deref_mir_constant()` below will ICE with an unsized type
                         // (except slices, which are handled in a separate arm above).
                         let msg = format!("cannot use unsized non-slice type `{}` in constant patterns", pointee_ty);
@@ -534,7 +534,7 @@ impl<'tcx> ConstToPat<'tcx> {
             ty::Bool | ty::Char | ty::Int(_) | ty::Uint(_) | ty::FnDef(..) => {
                 PatKind::Constant { value: cv }
             }
-            ty::RawPtr(pointee) if pointee.ty.is_sized(tcx.at(span), param_env) => {
+            ty::RawPtr(pointee) if pointee.ty.is_sized(tcx, param_env) => {
                 PatKind::Constant { value: cv }
             }
             // FIXME: these can have very surprising behaviour where optimization levels or other
diff --git a/compiler/rustc_mir_build/src/thir/pattern/mod.rs b/compiler/rustc_mir_build/src/thir/pattern/mod.rs
index 895af80bd7f3..80b532aec6c1 100644
--- a/compiler/rustc_mir_build/src/thir/pattern/mod.rs
+++ b/compiler/rustc_mir_build/src/thir/pattern/mod.rs
@@ -483,7 +483,12 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> {
         // Use `Reveal::All` here because patterns are always monomorphic even if their function
         // isn't.
         let param_env_reveal_all = self.param_env.with_reveal_all_normalized(self.tcx);
-        let substs = self.typeck_results.node_substs(id);
+        // N.B. There is no guarantee that substs collected in typeck results are fully normalized,
+        // so they need to be normalized in order to pass to `Instance::resolve`, which will ICE
+        // if given unnormalized types.
+        let substs = self
+            .tcx
+            .normalize_erasing_regions(param_env_reveal_all, self.typeck_results.node_substs(id));
         let instance = match ty::Instance::resolve(self.tcx, param_env_reveal_all, def_id, substs) {
             Ok(Some(i)) => i,
             Ok(None) => {
@@ -572,6 +577,9 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> {
                     self.errors.push(PatternError::ConstParamInPattern(span));
                     return PatKind::Wild;
                 }
+                ConstKind::Error(_) => {
+                    return PatKind::Wild;
+                }
                 _ => bug!("Expected ConstKind::Param"),
             },
             mir::ConstantKind::Val(_, _) => self.const_to_pat(value, id, span, false).kind,
@@ -609,7 +617,7 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> {
             LitToConstInput { lit: &lit.node, ty: self.typeck_results.expr_ty(expr), neg };
         match self.tcx.at(expr.span).lit_to_mir_constant(lit_input) {
             Ok(constant) => self.const_to_pat(constant, expr.hir_id, lit.span, false).kind,
-            Err(LitToConstError::Reported) => PatKind::Wild,
+            Err(LitToConstError::Reported(_)) => PatKind::Wild,
             Err(LitToConstError::TypeError) => bug!("lower_lit: had type error"),
         }
     }
diff --git a/compiler/rustc_mir_dataflow/src/elaborate_drops.rs b/compiler/rustc_mir_dataflow/src/elaborate_drops.rs
index 23403628c53f..14d265a402ef 100644
--- a/compiler/rustc_mir_dataflow/src/elaborate_drops.rs
+++ b/compiler/rustc_mir_dataflow/src/elaborate_drops.rs
@@ -407,9 +407,8 @@ where
         self.drop_ladder(fields, succ, unwind).0
     }
 
+    #[instrument(level = "debug", ret)]
     fn open_drop_for_box(&mut self, adt: ty::AdtDef<'tcx>, substs: SubstsRef<'tcx>) -> BasicBlock {
-        debug!("open_drop_for_box({:?}, {:?}, {:?})", self, adt, substs);
-
         // drop glue is sent straight to codegen
         // box cannot be directly dereferenced
         let unique_ty = adt.non_enum_variant().fields[0].ty(self.tcx(), substs);
@@ -431,8 +430,8 @@ where
         self.drop_subpath(interior, interior_path, succ, unwind_succ)
     }
 
+    #[instrument(level = "debug", ret)]
     fn open_drop_for_adt(&mut self, adt: ty::AdtDef<'tcx>, substs: SubstsRef<'tcx>) -> BasicBlock {
-        debug!("open_drop_for_adt({:?}, {:?}, {:?})", self, adt, substs);
         if adt.variants().is_empty() {
             return self.elaborator.patch().new_block(BasicBlockData {
                 statements: vec![],
diff --git a/compiler/rustc_mir_dataflow/src/framework/graphviz.rs b/compiler/rustc_mir_dataflow/src/framework/graphviz.rs
index 579fe68a1493..c9d5601f2074 100644
--- a/compiler/rustc_mir_dataflow/src/framework/graphviz.rs
+++ b/compiler/rustc_mir_dataflow/src/framework/graphviz.rs
@@ -475,7 +475,10 @@ where
                 r#"<td colspan="{colspan}" {fmt} align="left">{state}</td>"#,
                 colspan = this.style.num_state_columns(),
                 fmt = fmt,
-                state = format!("{:?}", DebugWithAdapter { this: state, ctxt: analysis }),
+                state = dot::escape_html(&format!(
+                    "{:?}",
+                    DebugWithAdapter { this: state, ctxt: analysis }
+                )),
             )
         })
     }
diff --git a/compiler/rustc_mir_dataflow/src/framework/lattice.rs b/compiler/rustc_mir_dataflow/src/framework/lattice.rs
index d6b89eb82275..f0e75c53ea15 100644
--- a/compiler/rustc_mir_dataflow/src/framework/lattice.rs
+++ b/compiler/rustc_mir_dataflow/src/framework/lattice.rs
@@ -73,6 +73,16 @@ pub trait MeetSemiLattice: Eq {
     fn meet(&mut self, other: &Self) -> bool;
 }
 
+/// A set that has a "bottom" element, which is less than or equal to any other element.
+pub trait HasBottom {
+    fn bottom() -> Self;
+}
+
+/// A set that has a "top" element, which is greater than or equal to any other element.
+pub trait HasTop {
+    fn top() -> Self;
+}
+
 /// A `bool` is a "two-point" lattice with `true` as the top element and `false` as the bottom:
 ///
 /// ```text
@@ -102,6 +112,18 @@ impl MeetSemiLattice for bool {
     }
 }
 
+impl HasBottom for bool {
+    fn bottom() -> Self {
+        false
+    }
+}
+
+impl HasTop for bool {
+    fn top() -> Self {
+        true
+    }
+}
+
 /// A tuple (or list) of lattices is itself a lattice whose least upper bound is the concatenation
 /// of the least upper bounds of each element of the tuple (or list).
 ///
@@ -250,3 +272,15 @@ impl<T: Clone + Eq> MeetSemiLattice for FlatSet<T> {
         true
     }
 }
+
+impl<T> HasBottom for FlatSet<T> {
+    fn bottom() -> Self {
+        Self::Bottom
+    }
+}
+
+impl<T> HasTop for FlatSet<T> {
+    fn top() -> Self {
+        Self::Top
+    }
+}
diff --git a/compiler/rustc_mir_dataflow/src/lib.rs b/compiler/rustc_mir_dataflow/src/lib.rs
index b471d04fd606..7f40cfca32ff 100644
--- a/compiler/rustc_mir_dataflow/src/lib.rs
+++ b/compiler/rustc_mir_dataflow/src/lib.rs
@@ -41,6 +41,7 @@ pub mod move_paths;
 pub mod rustc_peek;
 pub mod storage;
 pub mod un_derefer;
+pub mod value_analysis;
 
 pub(crate) mod indexes {
     pub(crate) use super::move_paths::MovePathIndex;
diff --git a/compiler/rustc_mir_dataflow/src/value_analysis.rs b/compiler/rustc_mir_dataflow/src/value_analysis.rs
new file mode 100644
index 000000000000..db4b0a3deda9
--- /dev/null
+++ b/compiler/rustc_mir_dataflow/src/value_analysis.rs
@@ -0,0 +1,927 @@
+//! This module provides a framework on top of the normal MIR dataflow framework to simplify the
+//! implementation of analyses that track information about the values stored in certain places.
+//! We are using the term "place" here to refer to a `mir::Place` (a place expression) instead of
+//! an `interpret::Place` (a memory location).
+//!
+//! The default methods of [`ValueAnalysis`] (prefixed with `super_` instead of `handle_`)
+//! provide some behavior that should be valid for all abstract domains that are based only on the
+//! value stored in a certain place. On top of these default rules, an implementation should
+//! override some of the `handle_` methods. For an example, see `ConstAnalysis`.
+//!
+//! An implementation must also provide a [`Map`]. Before the analysis begins, all places that
+//! should be tracked during the analysis must be registered. During the analysis, no new places
+//! can be registered. The [`State`] can be queried to retrieve the abstract value stored for a
+//! certain place by passing the map.
+//!
+//! This framework is currently experimental. Originally, it supported shared references and enum
+//! variants. However, it was discovered that both of these were unsound, and especially references
+//! had subtle but serious issues. In the future, they could be added back in, but we should clarify
+//! the rules for optimizations that rely on the aliasing model first.
+//!
+//!
+//! # Notes
+//!
+//! - The bottom state denotes uninitialized memory. Because we are only doing a sound approximation
+//! of the actual execution, we can also use this state for places where access would be UB.
+//!
+//! - The assignment logic in `State::assign_place_idx` assumes that the places are non-overlapping,
+//! or identical. Note that this refers to place expressions, not memory locations.
+//!
+//! - Currently, places that have their reference taken cannot be tracked. Although this would be
+//! possible, it has to rely on some aliasing model, which we are not ready to commit to yet.
+//! Because of that, we can assume that the only way to change the value behind a tracked place is
+//! by direct assignment.
+
+use std::fmt::{Debug, Formatter};
+
+use rustc_data_structures::fx::FxHashMap;
+use rustc_index::vec::IndexVec;
+use rustc_middle::mir::visit::{MutatingUseContext, PlaceContext, Visitor};
+use rustc_middle::mir::*;
+use rustc_middle::ty::{self, Ty, TyCtxt};
+use rustc_target::abi::VariantIdx;
+
+use crate::lattice::{HasBottom, HasTop};
+use crate::{
+    fmt::DebugWithContext, Analysis, AnalysisDomain, CallReturnPlaces, JoinSemiLattice,
+    SwitchIntEdgeEffects,
+};
+
+pub trait ValueAnalysis<'tcx> {
+    /// For each place of interest, the analysis tracks a value of the given type.
+    type Value: Clone + JoinSemiLattice + HasBottom + HasTop;
+
+    const NAME: &'static str;
+
+    fn map(&self) -> &Map;
+
+    fn handle_statement(&self, statement: &Statement<'tcx>, state: &mut State<Self::Value>) {
+        self.super_statement(statement, state)
+    }
+
+    fn super_statement(&self, statement: &Statement<'tcx>, state: &mut State<Self::Value>) {
+        match &statement.kind {
+            StatementKind::Assign(box (place, rvalue)) => {
+                self.handle_assign(*place, rvalue, state);
+            }
+            StatementKind::SetDiscriminant { .. } => {
+                // Could treat this as writing a constant to a pseudo-place.
+                // But discriminants are currently not tracked, so we do nothing.
+                // Related: https://github.com/rust-lang/unsafe-code-guidelines/issues/84
+            }
+            StatementKind::Intrinsic(box intrinsic) => {
+                self.handle_intrinsic(intrinsic, state);
+            }
+            StatementKind::StorageLive(local) | StatementKind::StorageDead(local) => {
+                // StorageLive leaves the local in an uninitialized state.
+                // StorageDead makes it UB to access the local afterwards.
+                state.flood_with(Place::from(*local).as_ref(), self.map(), Self::Value::bottom());
+            }
+            StatementKind::Deinit(box place) => {
+                // Deinit makes the place uninitialized.
+                state.flood_with(place.as_ref(), self.map(), Self::Value::bottom());
+            }
+            StatementKind::Retag(..) => {
+                // We don't track references.
+            }
+            StatementKind::Nop
+            | StatementKind::FakeRead(..)
+            | StatementKind::Coverage(..)
+            | StatementKind::AscribeUserType(..) => (),
+        }
+    }
+
+    fn handle_intrinsic(
+        &self,
+        intrinsic: &NonDivergingIntrinsic<'tcx>,
+        state: &mut State<Self::Value>,
+    ) {
+        self.super_intrinsic(intrinsic, state);
+    }
+
+    fn super_intrinsic(
+        &self,
+        intrinsic: &NonDivergingIntrinsic<'tcx>,
+        state: &mut State<Self::Value>,
+    ) {
+        match intrinsic {
+            NonDivergingIntrinsic::Assume(..) => {
+                // Could use this, but ignoring it is sound.
+            }
+            NonDivergingIntrinsic::CopyNonOverlapping(CopyNonOverlapping { dst, .. }) => {
+                if let Some(place) = dst.place() {
+                    state.flood(place.as_ref(), self.map());
+                }
+            }
+        }
+    }
+
+    fn handle_assign(
+        &self,
+        target: Place<'tcx>,
+        rvalue: &Rvalue<'tcx>,
+        state: &mut State<Self::Value>,
+    ) {
+        self.super_assign(target, rvalue, state)
+    }
+
+    fn super_assign(
+        &self,
+        target: Place<'tcx>,
+        rvalue: &Rvalue<'tcx>,
+        state: &mut State<Self::Value>,
+    ) {
+        let result = self.handle_rvalue(rvalue, state);
+        state.assign(target.as_ref(), result, self.map());
+    }
+
+    fn handle_rvalue(
+        &self,
+        rvalue: &Rvalue<'tcx>,
+        state: &mut State<Self::Value>,
+    ) -> ValueOrPlace<Self::Value> {
+        self.super_rvalue(rvalue, state)
+    }
+
+    fn super_rvalue(
+        &self,
+        rvalue: &Rvalue<'tcx>,
+        state: &mut State<Self::Value>,
+    ) -> ValueOrPlace<Self::Value> {
+        match rvalue {
+            Rvalue::Use(operand) => self.handle_operand(operand, state),
+            Rvalue::CopyForDeref(place) => self.handle_operand(&Operand::Copy(*place), state),
+            Rvalue::Ref(..) | Rvalue::AddressOf(..) => {
+                // We don't track such places.
+                ValueOrPlace::top()
+            }
+            Rvalue::Repeat(..)
+            | Rvalue::ThreadLocalRef(..)
+            | Rvalue::Len(..)
+            | Rvalue::Cast(..)
+            | Rvalue::BinaryOp(..)
+            | Rvalue::CheckedBinaryOp(..)
+            | Rvalue::NullaryOp(..)
+            | Rvalue::UnaryOp(..)
+            | Rvalue::Discriminant(..)
+            | Rvalue::Aggregate(..)
+            | Rvalue::ShallowInitBox(..) => {
+                // No modification is possible through these r-values.
+                ValueOrPlace::top()
+            }
+        }
+    }
+
+    fn handle_operand(
+        &self,
+        operand: &Operand<'tcx>,
+        state: &mut State<Self::Value>,
+    ) -> ValueOrPlace<Self::Value> {
+        self.super_operand(operand, state)
+    }
+
+    fn super_operand(
+        &self,
+        operand: &Operand<'tcx>,
+        state: &mut State<Self::Value>,
+    ) -> ValueOrPlace<Self::Value> {
+        match operand {
+            Operand::Constant(box constant) => {
+                ValueOrPlace::Value(self.handle_constant(constant, state))
+            }
+            Operand::Copy(place) | Operand::Move(place) => {
+                // On move, we would ideally flood the place with bottom. But with the current
+                // framework this is not possible (similar to `InterpCx::eval_operand`).
+                self.map()
+                    .find(place.as_ref())
+                    .map(ValueOrPlace::Place)
+                    .unwrap_or(ValueOrPlace::top())
+            }
+        }
+    }
+
+    fn handle_constant(
+        &self,
+        constant: &Constant<'tcx>,
+        state: &mut State<Self::Value>,
+    ) -> Self::Value {
+        self.super_constant(constant, state)
+    }
+
+    fn super_constant(
+        &self,
+        _constant: &Constant<'tcx>,
+        _state: &mut State<Self::Value>,
+    ) -> Self::Value {
+        Self::Value::top()
+    }
+
+    /// The effect of a successful function call return should not be
+    /// applied here, see [`Analysis::apply_terminator_effect`].
+    fn handle_terminator(&self, terminator: &Terminator<'tcx>, state: &mut State<Self::Value>) {
+        self.super_terminator(terminator, state)
+    }
+
+    fn super_terminator(&self, terminator: &Terminator<'tcx>, _state: &mut State<Self::Value>) {
+        match &terminator.kind {
+            TerminatorKind::Call { .. } | TerminatorKind::InlineAsm { .. } => {
+                // Effect is applied by `handle_call_return`.
+            }
+            TerminatorKind::Drop { .. } => {
+                // We don't track dropped places.
+            }
+            TerminatorKind::DropAndReplace { .. } | TerminatorKind::Yield { .. } => {
+                // They would have an effect, but are not allowed in this phase.
+                bug!("encountered disallowed terminator");
+            }
+            TerminatorKind::Goto { .. }
+            | TerminatorKind::SwitchInt { .. }
+            | TerminatorKind::Resume
+            | TerminatorKind::Abort
+            | TerminatorKind::Return
+            | TerminatorKind::Unreachable
+            | TerminatorKind::Assert { .. }
+            | TerminatorKind::GeneratorDrop
+            | TerminatorKind::FalseEdge { .. }
+            | TerminatorKind::FalseUnwind { .. } => {
+                // These terminators have no effect on the analysis.
+            }
+        }
+    }
+
+    fn handle_call_return(
+        &self,
+        return_places: CallReturnPlaces<'_, 'tcx>,
+        state: &mut State<Self::Value>,
+    ) {
+        self.super_call_return(return_places, state)
+    }
+
+    fn super_call_return(
+        &self,
+        return_places: CallReturnPlaces<'_, 'tcx>,
+        state: &mut State<Self::Value>,
+    ) {
+        return_places.for_each(|place| {
+            state.flood(place.as_ref(), self.map());
+        })
+    }
+
+    fn handle_switch_int(
+        &self,
+        discr: &Operand<'tcx>,
+        apply_edge_effects: &mut impl SwitchIntEdgeEffects<State<Self::Value>>,
+    ) {
+        self.super_switch_int(discr, apply_edge_effects)
+    }
+
+    fn super_switch_int(
+        &self,
+        _discr: &Operand<'tcx>,
+        _apply_edge_effects: &mut impl SwitchIntEdgeEffects<State<Self::Value>>,
+    ) {
+    }
+
+    fn wrap(self) -> ValueAnalysisWrapper<Self>
+    where
+        Self: Sized,
+    {
+        ValueAnalysisWrapper(self)
+    }
+}
+
+pub struct ValueAnalysisWrapper<T>(pub T);
+
+impl<'tcx, T: ValueAnalysis<'tcx>> AnalysisDomain<'tcx> for ValueAnalysisWrapper<T> {
+    type Domain = State<T::Value>;
+
+    type Direction = crate::Forward;
+
+    const NAME: &'static str = T::NAME;
+
+    fn bottom_value(&self, _body: &Body<'tcx>) -> Self::Domain {
+        State(StateData::Unreachable)
+    }
+
+    fn initialize_start_block(&self, body: &Body<'tcx>, state: &mut Self::Domain) {
+        // The initial state maps all tracked places of argument projections to ⊤ and the rest to ⊥.
+        assert!(matches!(state.0, StateData::Unreachable));
+        let values = IndexVec::from_elem_n(T::Value::bottom(), self.0.map().value_count);
+        *state = State(StateData::Reachable(values));
+        for arg in body.args_iter() {
+            state.flood(PlaceRef { local: arg, projection: &[] }, self.0.map());
+        }
+    }
+}
+
+impl<'tcx, T> Analysis<'tcx> for ValueAnalysisWrapper<T>
+where
+    T: ValueAnalysis<'tcx>,
+{
+    fn apply_statement_effect(
+        &self,
+        state: &mut Self::Domain,
+        statement: &Statement<'tcx>,
+        _location: Location,
+    ) {
+        if state.is_reachable() {
+            self.0.handle_statement(statement, state);
+        }
+    }
+
+    fn apply_terminator_effect(
+        &self,
+        state: &mut Self::Domain,
+        terminator: &Terminator<'tcx>,
+        _location: Location,
+    ) {
+        if state.is_reachable() {
+            self.0.handle_terminator(terminator, state);
+        }
+    }
+
+    fn apply_call_return_effect(
+        &self,
+        state: &mut Self::Domain,
+        _block: BasicBlock,
+        return_places: crate::CallReturnPlaces<'_, 'tcx>,
+    ) {
+        if state.is_reachable() {
+            self.0.handle_call_return(return_places, state)
+        }
+    }
+
+    fn apply_switch_int_edge_effects(
+        &self,
+        _block: BasicBlock,
+        discr: &Operand<'tcx>,
+        apply_edge_effects: &mut impl SwitchIntEdgeEffects<Self::Domain>,
+    ) {
+        // FIXME: Dataflow framework provides no access to current state here.
+        self.0.handle_switch_int(discr, apply_edge_effects)
+    }
+}
+
+rustc_index::newtype_index!(
+    /// This index uniquely identifies a place.
+    ///
+    /// Not every place has a `PlaceIndex`, and not every `PlaceIndex` correspondends to a tracked
+    /// place. However, every tracked place and all places along its projection have a `PlaceIndex`.
+    pub struct PlaceIndex {}
+);
+
+rustc_index::newtype_index!(
+    /// This index uniquely identifies a tracked place and therefore a slot in [`State`].
+    ///
+    /// It is an implementation detail of this module.
+    struct ValueIndex {}
+);
+
+/// See [`State`].
+#[derive(PartialEq, Eq, Debug)]
+enum StateData<V> {
+    Reachable(IndexVec<ValueIndex, V>),
+    Unreachable,
+}
+
+impl<V: Clone> Clone for StateData<V> {
+    fn clone(&self) -> Self {
+        match self {
+            Self::Reachable(x) => Self::Reachable(x.clone()),
+            Self::Unreachable => Self::Unreachable,
+        }
+    }
+
+    fn clone_from(&mut self, source: &Self) {
+        match (&mut *self, source) {
+            (Self::Reachable(x), Self::Reachable(y)) => {
+                // We go through `raw` here, because `IndexVec` currently has a naive `clone_from`.
+                x.raw.clone_from(&y.raw);
+            }
+            _ => *self = source.clone(),
+        }
+    }
+}
+
+/// The dataflow state for an instance of [`ValueAnalysis`].
+///
+/// Every instance specifies a lattice that represents the possible values of a single tracked
+/// place. If we call this lattice `V` and set set of tracked places `P`, then a [`State`] is an
+/// element of `{unreachable} ∪ (P -> V)`. This again forms a lattice, where the bottom element is
+/// `unreachable` and the top element is the mapping `p ↦ ⊤`. Note that the mapping `p ↦ ⊥` is not
+/// the bottom element (because joining an unreachable and any other reachable state yields a
+/// reachable state). All operations on unreachable states are ignored.
+///
+/// Flooding means assigning a value (by default `⊤`) to all tracked projections of a given place.
+#[derive(PartialEq, Eq, Debug)]
+pub struct State<V>(StateData<V>);
+
+impl<V: Clone> Clone for State<V> {
+    fn clone(&self) -> Self {
+        Self(self.0.clone())
+    }
+
+    fn clone_from(&mut self, source: &Self) {
+        self.0.clone_from(&source.0);
+    }
+}
+
+impl<V: Clone + HasTop + HasBottom> State<V> {
+    pub fn is_reachable(&self) -> bool {
+        matches!(&self.0, StateData::Reachable(_))
+    }
+
+    pub fn mark_unreachable(&mut self) {
+        self.0 = StateData::Unreachable;
+    }
+
+    pub fn flood_all(&mut self) {
+        self.flood_all_with(V::top())
+    }
+
+    pub fn flood_all_with(&mut self, value: V) {
+        let StateData::Reachable(values) = &mut self.0 else { return };
+        values.raw.fill(value);
+    }
+
+    pub fn flood_with(&mut self, place: PlaceRef<'_>, map: &Map, value: V) {
+        if let Some(root) = map.find(place) {
+            self.flood_idx_with(root, map, value);
+        }
+    }
+
+    pub fn flood(&mut self, place: PlaceRef<'_>, map: &Map) {
+        self.flood_with(place, map, V::top())
+    }
+
+    pub fn flood_idx_with(&mut self, place: PlaceIndex, map: &Map, value: V) {
+        let StateData::Reachable(values) = &mut self.0 else { return };
+        map.preorder_invoke(place, &mut |place| {
+            if let Some(vi) = map.places[place].value_index {
+                values[vi] = value.clone();
+            }
+        });
+    }
+
+    pub fn flood_idx(&mut self, place: PlaceIndex, map: &Map) {
+        self.flood_idx_with(place, map, V::top())
+    }
+
+    /// Copies `source` to `target`, including all tracked places beneath.
+    ///
+    /// If `target` contains a place that is not contained in `source`, it will be overwritten with
+    /// Top. Also, because this will copy all entries one after another, it may only be used for
+    /// places that are non-overlapping or identical.
+    pub fn assign_place_idx(&mut self, target: PlaceIndex, source: PlaceIndex, map: &Map) {
+        let StateData::Reachable(values) = &mut self.0 else { return };
+
+        // If both places are tracked, we copy the value to the target. If the target is tracked,
+        // but the source is not, we have to invalidate the value in target. If the target is not
+        // tracked, then we don't have to do anything.
+        if let Some(target_value) = map.places[target].value_index {
+            if let Some(source_value) = map.places[source].value_index {
+                values[target_value] = values[source_value].clone();
+            } else {
+                values[target_value] = V::top();
+            }
+        }
+        for target_child in map.children(target) {
+            // Try to find corresponding child and recurse. Reasoning is similar as above.
+            let projection = map.places[target_child].proj_elem.unwrap();
+            if let Some(source_child) = map.projections.get(&(source, projection)) {
+                self.assign_place_idx(target_child, *source_child, map);
+            } else {
+                self.flood_idx(target_child, map);
+            }
+        }
+    }
+
+    pub fn assign(&mut self, target: PlaceRef<'_>, result: ValueOrPlace<V>, map: &Map) {
+        if let Some(target) = map.find(target) {
+            self.assign_idx(target, result, map);
+        } else {
+            // We don't track this place nor any projections, assignment can be ignored.
+        }
+    }
+
+    pub fn assign_idx(&mut self, target: PlaceIndex, result: ValueOrPlace<V>, map: &Map) {
+        match result {
+            ValueOrPlace::Value(value) => {
+                // First flood the target place in case we also track any projections (although
+                // this scenario is currently not well-supported by the API).
+                self.flood_idx(target, map);
+                let StateData::Reachable(values) = &mut self.0 else { return };
+                if let Some(value_index) = map.places[target].value_index {
+                    values[value_index] = value;
+                }
+            }
+            ValueOrPlace::Place(source) => self.assign_place_idx(target, source, map),
+        }
+    }
+
+    /// Retrieve the value stored for a place, or ⊤ if it is not tracked.
+    pub fn get(&self, place: PlaceRef<'_>, map: &Map) -> V {
+        map.find(place).map(|place| self.get_idx(place, map)).unwrap_or(V::top())
+    }
+
+    /// Retrieve the value stored for a place index, or ⊤ if it is not tracked.
+    pub fn get_idx(&self, place: PlaceIndex, map: &Map) -> V {
+        match &self.0 {
+            StateData::Reachable(values) => {
+                map.places[place].value_index.map(|v| values[v].clone()).unwrap_or(V::top())
+            }
+            StateData::Unreachable => {
+                // Because this is unreachable, we can return any value we want.
+                V::bottom()
+            }
+        }
+    }
+}
+
+impl<V: JoinSemiLattice + Clone> JoinSemiLattice for State<V> {
+    fn join(&mut self, other: &Self) -> bool {
+        match (&mut self.0, &other.0) {
+            (_, StateData::Unreachable) => false,
+            (StateData::Unreachable, _) => {
+                *self = other.clone();
+                true
+            }
+            (StateData::Reachable(this), StateData::Reachable(other)) => this.join(other),
+        }
+    }
+}
+
+/// Partial mapping from [`Place`] to [`PlaceIndex`], where some places also have a [`ValueIndex`].
+///
+/// This data structure essentially maintains a tree of places and their projections. Some
+/// additional bookkeeping is done, to speed up traversal over this tree:
+/// - For iteration, every [`PlaceInfo`] contains an intrusive linked list of its children.
+/// - To directly get the child for a specific projection, there is a `projections` map.
+#[derive(Debug)]
+pub struct Map {
+    locals: IndexVec<Local, Option<PlaceIndex>>,
+    projections: FxHashMap<(PlaceIndex, TrackElem), PlaceIndex>,
+    places: IndexVec<PlaceIndex, PlaceInfo>,
+    value_count: usize,
+}
+
+impl Map {
+    fn new() -> Self {
+        Self {
+            locals: IndexVec::new(),
+            projections: FxHashMap::default(),
+            places: IndexVec::new(),
+            value_count: 0,
+        }
+    }
+
+    /// Returns a map that only tracks places whose type passes the filter.
+    ///
+    /// This is currently the only way to create a [`Map`]. The way in which the tracked places are
+    /// chosen is an implementation detail and may not be relied upon (other than that their type
+    /// passes the filter).
+    #[instrument(skip_all, level = "debug")]
+    pub fn from_filter<'tcx>(
+        tcx: TyCtxt<'tcx>,
+        body: &Body<'tcx>,
+        filter: impl FnMut(Ty<'tcx>) -> bool,
+    ) -> Self {
+        let mut map = Self::new();
+        let exclude = excluded_locals(body);
+        map.register_with_filter(tcx, body, filter, &exclude);
+        debug!("registered {} places ({} nodes in total)", map.value_count, map.places.len());
+        map
+    }
+
+    /// Register all non-excluded places that pass the filter.
+    fn register_with_filter<'tcx>(
+        &mut self,
+        tcx: TyCtxt<'tcx>,
+        body: &Body<'tcx>,
+        mut filter: impl FnMut(Ty<'tcx>) -> bool,
+        exclude: &IndexVec<Local, bool>,
+    ) {
+        // We use this vector as stack, pushing and popping projections.
+        let mut projection = Vec::new();
+        for (local, decl) in body.local_decls.iter_enumerated() {
+            if !exclude[local] {
+                self.register_with_filter_rec(tcx, local, &mut projection, decl.ty, &mut filter);
+            }
+        }
+    }
+
+    /// Potentially register the (local, projection) place and its fields, recursively.
+    ///
+    /// Invariant: The projection must only contain fields.
+    fn register_with_filter_rec<'tcx>(
+        &mut self,
+        tcx: TyCtxt<'tcx>,
+        local: Local,
+        projection: &mut Vec<PlaceElem<'tcx>>,
+        ty: Ty<'tcx>,
+        filter: &mut impl FnMut(Ty<'tcx>) -> bool,
+    ) {
+        // Note: The framework supports only scalars for now.
+        if filter(ty) && ty.is_scalar() {
+            // We know that the projection only contains trackable elements.
+            let place = self.make_place(local, projection).unwrap();
+
+            // Allocate a value slot if it doesn't have one.
+            if self.places[place].value_index.is_none() {
+                self.places[place].value_index = Some(self.value_count.into());
+                self.value_count += 1;
+            }
+        }
+
+        // Recurse with all fields of this place.
+        iter_fields(ty, tcx, |variant, field, ty| {
+            if variant.is_some() {
+                // Downcasts are currently not supported.
+                return;
+            }
+            projection.push(PlaceElem::Field(field, ty));
+            self.register_with_filter_rec(tcx, local, projection, ty, filter);
+            projection.pop();
+        });
+    }
+
+    /// Tries to add the place to the map, without allocating a value slot.
+    ///
+    /// Can fail if the projection contains non-trackable elements.
+    fn make_place<'tcx>(
+        &mut self,
+        local: Local,
+        projection: &[PlaceElem<'tcx>],
+    ) -> Result<PlaceIndex, ()> {
+        // Get the base index of the local.
+        let mut index =
+            *self.locals.get_or_insert_with(local, || self.places.push(PlaceInfo::new(None)));
+
+        // Apply the projection.
+        for &elem in projection {
+            let elem = elem.try_into()?;
+            index = *self.projections.entry((index, elem)).or_insert_with(|| {
+                // Prepend new child to the linked list.
+                let next = self.places.push(PlaceInfo::new(Some(elem)));
+                self.places[next].next_sibling = self.places[index].first_child;
+                self.places[index].first_child = Some(next);
+                next
+            });
+        }
+
+        Ok(index)
+    }
+
+    /// Returns the number of tracked places, i.e., those for which a value can be stored.
+    pub fn tracked_places(&self) -> usize {
+        self.value_count
+    }
+
+    /// Applies a single projection element, yielding the corresponding child.
+    pub fn apply(&self, place: PlaceIndex, elem: TrackElem) -> Option<PlaceIndex> {
+        self.projections.get(&(place, elem)).copied()
+    }
+
+    /// Locates the given place, if it exists in the tree.
+    pub fn find(&self, place: PlaceRef<'_>) -> Option<PlaceIndex> {
+        let mut index = *self.locals.get(place.local)?.as_ref()?;
+
+        for &elem in place.projection {
+            index = self.apply(index, elem.try_into().ok()?)?;
+        }
+
+        Some(index)
+    }
+
+    /// Iterate over all direct children.
+    pub fn children(&self, parent: PlaceIndex) -> impl Iterator<Item = PlaceIndex> + '_ {
+        Children::new(self, parent)
+    }
+
+    /// Invoke a function on the given place and all descendants.
+    pub fn preorder_invoke(&self, root: PlaceIndex, f: &mut impl FnMut(PlaceIndex)) {
+        f(root);
+        for child in self.children(root) {
+            self.preorder_invoke(child, f);
+        }
+    }
+}
+
+/// This is the information tracked for every [`PlaceIndex`] and is stored by [`Map`].
+///
+/// Together, `first_child` and `next_sibling` form an intrusive linked list, which is used to
+/// model a tree structure (a replacement for a member like `children: Vec<PlaceIndex>`).
+#[derive(Debug)]
+struct PlaceInfo {
+    /// We store a [`ValueIndex`] if and only if the placed is tracked by the analysis.
+    value_index: Option<ValueIndex>,
+
+    /// The projection used to go from parent to this node (only None for root).
+    proj_elem: Option<TrackElem>,
+
+    /// The left-most child.
+    first_child: Option<PlaceIndex>,
+
+    /// Index of the sibling to the right of this node.
+    next_sibling: Option<PlaceIndex>,
+}
+
+impl PlaceInfo {
+    fn new(proj_elem: Option<TrackElem>) -> Self {
+        Self { next_sibling: None, first_child: None, proj_elem, value_index: None }
+    }
+}
+
+struct Children<'a> {
+    map: &'a Map,
+    next: Option<PlaceIndex>,
+}
+
+impl<'a> Children<'a> {
+    fn new(map: &'a Map, parent: PlaceIndex) -> Self {
+        Self { map, next: map.places[parent].first_child }
+    }
+}
+
+impl<'a> Iterator for Children<'a> {
+    type Item = PlaceIndex;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        match self.next {
+            Some(child) => {
+                self.next = self.map.places[child].next_sibling;
+                Some(child)
+            }
+            None => None,
+        }
+    }
+}
+
+/// Used as the result of an operand or r-value.
+pub enum ValueOrPlace<V> {
+    Value(V),
+    Place(PlaceIndex),
+}
+
+impl<V: HasTop> ValueOrPlace<V> {
+    pub fn top() -> Self {
+        ValueOrPlace::Value(V::top())
+    }
+}
+
+/// The set of projection elements that can be used by a tracked place.
+///
+/// Although only field projections are currently allowed, this could change in the future.
+#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
+pub enum TrackElem {
+    Field(Field),
+}
+
+impl<V, T> TryFrom<ProjectionElem<V, T>> for TrackElem {
+    type Error = ();
+
+    fn try_from(value: ProjectionElem<V, T>) -> Result<Self, Self::Error> {
+        match value {
+            ProjectionElem::Field(field, _) => Ok(TrackElem::Field(field)),
+            _ => Err(()),
+        }
+    }
+}
+
+/// Invokes `f` on all direct fields of `ty`.
+fn iter_fields<'tcx>(
+    ty: Ty<'tcx>,
+    tcx: TyCtxt<'tcx>,
+    mut f: impl FnMut(Option<VariantIdx>, Field, Ty<'tcx>),
+) {
+    match ty.kind() {
+        ty::Tuple(list) => {
+            for (field, ty) in list.iter().enumerate() {
+                f(None, field.into(), ty);
+            }
+        }
+        ty::Adt(def, substs) => {
+            if def.is_union() {
+                return;
+            }
+            for (v_index, v_def) in def.variants().iter_enumerated() {
+                let variant = if def.is_struct() { None } else { Some(v_index) };
+                for (f_index, f_def) in v_def.fields.iter().enumerate() {
+                    let field_ty = f_def.ty(tcx, substs);
+                    let field_ty = tcx
+                        .try_normalize_erasing_regions(ty::ParamEnv::reveal_all(), field_ty)
+                        .unwrap_or(field_ty);
+                    f(variant, f_index.into(), field_ty);
+                }
+            }
+        }
+        ty::Closure(_, substs) => {
+            iter_fields(substs.as_closure().tupled_upvars_ty(), tcx, f);
+        }
+        _ => (),
+    }
+}
+
+/// Returns all locals with projections that have their reference or address taken.
+fn excluded_locals<'tcx>(body: &Body<'tcx>) -> IndexVec<Local, bool> {
+    struct Collector {
+        result: IndexVec<Local, bool>,
+    }
+
+    impl<'tcx> Visitor<'tcx> for Collector {
+        fn visit_place(&mut self, place: &Place<'tcx>, context: PlaceContext, _location: Location) {
+            if context.is_borrow()
+                || context.is_address_of()
+                || context.is_drop()
+                || context == PlaceContext::MutatingUse(MutatingUseContext::AsmOutput)
+            {
+                // A pointer to a place could be used to access other places with the same local,
+                // hence we have to exclude the local completely.
+                self.result[place.local] = true;
+            }
+        }
+    }
+
+    let mut collector = Collector { result: IndexVec::from_elem(false, &body.local_decls) };
+    collector.visit_body(body);
+    collector.result
+}
+
+/// This is used to visualize the dataflow analysis.
+impl<'tcx, T> DebugWithContext<ValueAnalysisWrapper<T>> for State<T::Value>
+where
+    T: ValueAnalysis<'tcx>,
+    T::Value: Debug,
+{
+    fn fmt_with(&self, ctxt: &ValueAnalysisWrapper<T>, f: &mut Formatter<'_>) -> std::fmt::Result {
+        match &self.0 {
+            StateData::Reachable(values) => debug_with_context(values, None, ctxt.0.map(), f),
+            StateData::Unreachable => write!(f, "unreachable"),
+        }
+    }
+
+    fn fmt_diff_with(
+        &self,
+        old: &Self,
+        ctxt: &ValueAnalysisWrapper<T>,
+        f: &mut Formatter<'_>,
+    ) -> std::fmt::Result {
+        match (&self.0, &old.0) {
+            (StateData::Reachable(this), StateData::Reachable(old)) => {
+                debug_with_context(this, Some(old), ctxt.0.map(), f)
+            }
+            _ => Ok(()), // Consider printing something here.
+        }
+    }
+}
+
+fn debug_with_context_rec<V: Debug + Eq>(
+    place: PlaceIndex,
+    place_str: &str,
+    new: &IndexVec<ValueIndex, V>,
+    old: Option<&IndexVec<ValueIndex, V>>,
+    map: &Map,
+    f: &mut Formatter<'_>,
+) -> std::fmt::Result {
+    if let Some(value) = map.places[place].value_index {
+        match old {
+            None => writeln!(f, "{}: {:?}", place_str, new[value])?,
+            Some(old) => {
+                if new[value] != old[value] {
+                    writeln!(f, "\u{001f}-{}: {:?}", place_str, old[value])?;
+                    writeln!(f, "\u{001f}+{}: {:?}", place_str, new[value])?;
+                }
+            }
+        }
+    }
+
+    for child in map.children(place) {
+        let info_elem = map.places[child].proj_elem.unwrap();
+        let child_place_str = match info_elem {
+            TrackElem::Field(field) => {
+                if place_str.starts_with("*") {
+                    format!("({}).{}", place_str, field.index())
+                } else {
+                    format!("{}.{}", place_str, field.index())
+                }
+            }
+        };
+        debug_with_context_rec(child, &child_place_str, new, old, map, f)?;
+    }
+
+    Ok(())
+}
+
+fn debug_with_context<V: Debug + Eq>(
+    new: &IndexVec<ValueIndex, V>,
+    old: Option<&IndexVec<ValueIndex, V>>,
+    map: &Map,
+    f: &mut Formatter<'_>,
+) -> std::fmt::Result {
+    for (local, place) in map.locals.iter_enumerated() {
+        if let Some(place) = place {
+            debug_with_context_rec(*place, &format!("{:?}", local), new, old, map, f)?;
+        }
+    }
+    Ok(())
+}
diff --git a/compiler/rustc_mir_transform/src/check_unsafety.rs b/compiler/rustc_mir_transform/src/check_unsafety.rs
index 4730be1244bd..e783d1891377 100644
--- a/compiler/rustc_mir_transform/src/check_unsafety.rs
+++ b/compiler/rustc_mir_transform/src/check_unsafety.rs
@@ -4,6 +4,7 @@ use rustc_hir as hir;
 use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_hir::hir_id::HirId;
 use rustc_hir::intravisit;
+use rustc_hir::{BlockCheckMode, ExprKind, Node};
 use rustc_middle::mir::visit::{MutatingUseContext, PlaceContext, Visitor};
 use rustc_middle::mir::*;
 use rustc_middle::ty::query::Providers;
@@ -101,12 +102,10 @@ impl<'tcx> Visitor<'tcx> for UnsafetyChecker<'_, 'tcx> {
             | StatementKind::Retag { .. }
             | StatementKind::AscribeUserType(..)
             | StatementKind::Coverage(..)
+            | StatementKind::Intrinsic(..)
             | StatementKind::Nop => {
                 // safe (at least as emitted during MIR construction)
             }
-
-            // Move to above list once mir construction uses it.
-            StatementKind::Intrinsic(..) => unreachable!(),
         }
         self.super_statement(statement, location);
     }
@@ -312,7 +311,7 @@ impl<'tcx> UnsafetyChecker<'_, 'tcx> {
                             } else if !place
                                 .ty(self.body, self.tcx)
                                 .ty
-                                .is_freeze(self.tcx.at(self.source_info.span), self.param_env)
+                                .is_freeze(self.tcx, self.param_env)
                             {
                                 UnsafetyViolationDetails::BorrowOfLayoutConstrainedField
                             } else {
@@ -472,6 +471,14 @@ fn unsafety_check_result<'tcx>(
     // `mir_built` force this.
     let body = &tcx.mir_built(def).borrow();
 
+    if body.should_skip() {
+        return tcx.arena.alloc(UnsafetyCheckResult {
+            violations: Vec::new(),
+            used_unsafe_blocks: FxHashSet::default(),
+            unused_unsafes: Some(Vec::new()),
+        });
+    }
+
     let param_env = tcx.param_env(def.did);
 
     let mut checker = UnsafetyChecker::new(body, def.did, tcx, param_env);
@@ -519,24 +526,48 @@ pub fn check_unsafety(tcx: TyCtxt<'_>, def_id: LocalDefId) {
     for &UnsafetyViolation { source_info, lint_root, kind, details } in violations.iter() {
         let (description, note) = details.description_and_note();
 
-        // Report an error.
-        let unsafe_fn_msg =
-            if unsafe_op_in_unsafe_fn_allowed(tcx, lint_root) { " function or" } else { "" };
-
         match kind {
             UnsafetyViolationKind::General => {
                 // once
-                struct_span_err!(
+                let unsafe_fn_msg = if unsafe_op_in_unsafe_fn_allowed(tcx, lint_root) {
+                    " function or"
+                } else {
+                    ""
+                };
+
+                let mut err = struct_span_err!(
                     tcx.sess,
                     source_info.span,
                     E0133,
                     "{} is unsafe and requires unsafe{} block",
                     description,
                     unsafe_fn_msg,
-                )
-                .span_label(source_info.span, description)
-                .note(note)
-                .emit();
+                );
+                err.span_label(source_info.span, description).note(note);
+                let note_non_inherited = tcx.hir().parent_iter(lint_root).find(|(id, node)| {
+                    if let Node::Expr(block) = node
+                        && let ExprKind::Block(block, _) = block.kind
+                        && let BlockCheckMode::UnsafeBlock(_) = block.rules
+                    {
+                        true
+                    }
+                    else if let Some(sig) = tcx.hir().fn_sig_by_hir_id(*id)
+                        && sig.header.is_unsafe()
+                    {
+                        true
+                    } else {
+                        false
+                    }
+                });
+                if let Some((id, _)) = note_non_inherited {
+                    let span = tcx.hir().span(id);
+                    err.span_label(
+                        tcx.sess.source_map().guess_head_span(span),
+                        "items do not inherit unsafety from separate enclosing items",
+                    );
+                }
+
+                err.emit();
             }
             UnsafetyViolationKind::UnsafeFn => tcx.struct_span_lint_hir(
                 UNSAFE_OP_IN_UNSAFE_FN,
diff --git a/compiler/rustc_mir_transform/src/const_prop.rs b/compiler/rustc_mir_transform/src/const_prop.rs
index 4a9bd9df327f..4f30e8a0be03 100644
--- a/compiler/rustc_mir_transform/src/const_prop.rs
+++ b/compiler/rustc_mir_transform/src/const_prop.rs
@@ -385,7 +385,7 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> {
             // I don't know how return types can seem to be unsized but this happens in the
             // `type/type-unsatisfiable.rs` test.
             .filter(|ret_layout| {
-                !ret_layout.is_unsized() && ret_layout.size < Size::from_bytes(MAX_ALLOC_LIMIT)
+                ret_layout.is_sized() && ret_layout.size < Size::from_bytes(MAX_ALLOC_LIMIT)
             })
             .unwrap_or_else(|| ecx.layout_of(tcx.types.unit).unwrap());
 
@@ -633,7 +633,7 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> {
         }
         if !rvalue
             .ty(&self.ecx.frame().body.local_decls, *self.ecx.tcx)
-            .is_sized(self.ecx.tcx, self.param_env)
+            .is_sized(*self.ecx.tcx, self.param_env)
         {
             // the interpreter doesn't support unsized locals (only unsized arguments),
             // but rustc does (in a kinda broken way), so we have to skip them here
diff --git a/compiler/rustc_mir_transform/src/const_prop_lint.rs b/compiler/rustc_mir_transform/src/const_prop_lint.rs
index 6bddbdb8e6aa..163446c52e4c 100644
--- a/compiler/rustc_mir_transform/src/const_prop_lint.rs
+++ b/compiler/rustc_mir_transform/src/const_prop_lint.rs
@@ -199,7 +199,7 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> {
             // I don't know how return types can seem to be unsized but this happens in the
             // `type/type-unsatisfiable.rs` test.
             .filter(|ret_layout| {
-                !ret_layout.is_unsized() && ret_layout.size < Size::from_bytes(MAX_ALLOC_LIMIT)
+                ret_layout.is_sized() && ret_layout.size < Size::from_bytes(MAX_ALLOC_LIMIT)
             })
             .unwrap_or_else(|| ecx.layout_of(tcx.types.unit).unwrap());
 
@@ -500,7 +500,7 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> {
         }
         if !rvalue
             .ty(&self.ecx.frame().body.local_decls, *self.ecx.tcx)
-            .is_sized(self.ecx.tcx, self.param_env)
+            .is_sized(*self.ecx.tcx, self.param_env)
         {
             // the interpreter doesn't support unsized locals (only unsized arguments),
             // but rustc does (in a kinda broken way), so we have to skip them here
diff --git a/compiler/rustc_mir_transform/src/dataflow_const_prop.rs b/compiler/rustc_mir_transform/src/dataflow_const_prop.rs
new file mode 100644
index 000000000000..e9027387413c
--- /dev/null
+++ b/compiler/rustc_mir_transform/src/dataflow_const_prop.rs
@@ -0,0 +1,530 @@
+//! A constant propagation optimization pass based on dataflow analysis.
+//!
+//! Currently, this pass only propagates scalar values.
+
+use rustc_const_eval::interpret::{ConstValue, ImmTy, Immediate, InterpCx, Scalar};
+use rustc_data_structures::fx::FxHashMap;
+use rustc_middle::mir::visit::{MutVisitor, Visitor};
+use rustc_middle::mir::*;
+use rustc_middle::ty::{self, Ty, TyCtxt};
+use rustc_mir_dataflow::value_analysis::{Map, State, TrackElem, ValueAnalysis, ValueOrPlace};
+use rustc_mir_dataflow::{lattice::FlatSet, Analysis, ResultsVisitor, SwitchIntEdgeEffects};
+use rustc_span::DUMMY_SP;
+
+use crate::MirPass;
+
+// These constants are somewhat random guesses and have not been optimized.
+// If `tcx.sess.mir_opt_level() >= 4`, we ignore the limits (this can become very expensive).
+const BLOCK_LIMIT: usize = 100;
+const PLACE_LIMIT: usize = 100;
+
+pub struct DataflowConstProp;
+
+impl<'tcx> MirPass<'tcx> for DataflowConstProp {
+    fn is_enabled(&self, sess: &rustc_session::Session) -> bool {
+        sess.mir_opt_level() >= 3
+    }
+
+    #[instrument(skip_all level = "debug")]
+    fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
+        if tcx.sess.mir_opt_level() < 4 && body.basic_blocks.len() > BLOCK_LIMIT {
+            debug!("aborted dataflow const prop due too many basic blocks");
+            return;
+        }
+
+        // Decide which places to track during the analysis.
+        let map = Map::from_filter(tcx, body, Ty::is_scalar);
+
+        // We want to have a somewhat linear runtime w.r.t. the number of statements/terminators.
+        // Let's call this number `n`. Dataflow analysis has `O(h*n)` transfer function
+        // applications, where `h` is the height of the lattice. Because the height of our lattice
+        // is linear w.r.t. the number of tracked places, this is `O(tracked_places * n)`. However,
+        // because every transfer function application could traverse the whole map, this becomes
+        // `O(num_nodes * tracked_places * n)` in terms of time complexity. Since the number of
+        // map nodes is strongly correlated to the number of tracked places, this becomes more or
+        // less `O(n)` if we place a constant limit on the number of tracked places.
+        if tcx.sess.mir_opt_level() < 4 && map.tracked_places() > PLACE_LIMIT {
+            debug!("aborted dataflow const prop due to too many tracked places");
+            return;
+        }
+
+        // Perform the actual dataflow analysis.
+        let analysis = ConstAnalysis::new(tcx, body, map);
+        let results = debug_span!("analyze")
+            .in_scope(|| analysis.wrap().into_engine(tcx, body).iterate_to_fixpoint());
+
+        // Collect results and patch the body afterwards.
+        let mut visitor = CollectAndPatch::new(tcx, &results.analysis.0.map);
+        debug_span!("collect").in_scope(|| results.visit_reachable_with(body, &mut visitor));
+        debug_span!("patch").in_scope(|| visitor.visit_body(body));
+    }
+}
+
+struct ConstAnalysis<'tcx> {
+    map: Map,
+    tcx: TyCtxt<'tcx>,
+    ecx: InterpCx<'tcx, 'tcx, DummyMachine>,
+    param_env: ty::ParamEnv<'tcx>,
+}
+
+impl<'tcx> ValueAnalysis<'tcx> for ConstAnalysis<'tcx> {
+    type Value = FlatSet<ScalarTy<'tcx>>;
+
+    const NAME: &'static str = "ConstAnalysis";
+
+    fn map(&self) -> &Map {
+        &self.map
+    }
+
+    fn handle_assign(
+        &self,
+        target: Place<'tcx>,
+        rvalue: &Rvalue<'tcx>,
+        state: &mut State<Self::Value>,
+    ) {
+        match rvalue {
+            Rvalue::CheckedBinaryOp(op, box (left, right)) => {
+                let target = self.map().find(target.as_ref());
+                if let Some(target) = target {
+                    // We should not track any projections other than
+                    // what is overwritten below, but just in case...
+                    state.flood_idx(target, self.map());
+                }
+
+                let value_target = target
+                    .and_then(|target| self.map().apply(target, TrackElem::Field(0_u32.into())));
+                let overflow_target = target
+                    .and_then(|target| self.map().apply(target, TrackElem::Field(1_u32.into())));
+
+                if value_target.is_some() || overflow_target.is_some() {
+                    let (val, overflow) = self.binary_op(state, *op, left, right);
+
+                    if let Some(value_target) = value_target {
+                        state.assign_idx(value_target, ValueOrPlace::Value(val), self.map());
+                    }
+                    if let Some(overflow_target) = overflow_target {
+                        let overflow = match overflow {
+                            FlatSet::Top => FlatSet::Top,
+                            FlatSet::Elem(overflow) => {
+                                if overflow {
+                                    // Overflow cannot be reliably propagated. See: https://github.com/rust-lang/rust/pull/101168#issuecomment-1288091446
+                                    FlatSet::Top
+                                } else {
+                                    self.wrap_scalar(Scalar::from_bool(false), self.tcx.types.bool)
+                                }
+                            }
+                            FlatSet::Bottom => FlatSet::Bottom,
+                        };
+                        state.assign_idx(
+                            overflow_target,
+                            ValueOrPlace::Value(overflow),
+                            self.map(),
+                        );
+                    }
+                }
+            }
+            _ => self.super_assign(target, rvalue, state),
+        }
+    }
+
+    fn handle_rvalue(
+        &self,
+        rvalue: &Rvalue<'tcx>,
+        state: &mut State<Self::Value>,
+    ) -> ValueOrPlace<Self::Value> {
+        match rvalue {
+            Rvalue::Cast(
+                kind @ (CastKind::IntToInt
+                | CastKind::FloatToInt
+                | CastKind::FloatToFloat
+                | CastKind::IntToFloat),
+                operand,
+                ty,
+            ) => match self.eval_operand(operand, state) {
+                FlatSet::Elem(op) => match kind {
+                    CastKind::IntToInt | CastKind::IntToFloat => {
+                        self.ecx.int_to_int_or_float(&op, *ty)
+                    }
+                    CastKind::FloatToInt | CastKind::FloatToFloat => {
+                        self.ecx.float_to_float_or_int(&op, *ty)
+                    }
+                    _ => unreachable!(),
+                }
+                .map(|result| ValueOrPlace::Value(self.wrap_immediate(result, *ty)))
+                .unwrap_or(ValueOrPlace::top()),
+                _ => ValueOrPlace::top(),
+            },
+            Rvalue::BinaryOp(op, box (left, right)) => {
+                // Overflows must be ignored here.
+                let (val, _overflow) = self.binary_op(state, *op, left, right);
+                ValueOrPlace::Value(val)
+            }
+            Rvalue::UnaryOp(op, operand) => match self.eval_operand(operand, state) {
+                FlatSet::Elem(value) => self
+                    .ecx
+                    .unary_op(*op, &value)
+                    .map(|val| ValueOrPlace::Value(self.wrap_immty(val)))
+                    .unwrap_or(ValueOrPlace::Value(FlatSet::Top)),
+                FlatSet::Bottom => ValueOrPlace::Value(FlatSet::Bottom),
+                FlatSet::Top => ValueOrPlace::Value(FlatSet::Top),
+            },
+            _ => self.super_rvalue(rvalue, state),
+        }
+    }
+
+    fn handle_constant(
+        &self,
+        constant: &Constant<'tcx>,
+        _state: &mut State<Self::Value>,
+    ) -> Self::Value {
+        constant
+            .literal
+            .eval(self.tcx, self.param_env)
+            .try_to_scalar()
+            .map(|value| FlatSet::Elem(ScalarTy(value, constant.ty())))
+            .unwrap_or(FlatSet::Top)
+    }
+
+    fn handle_switch_int(
+        &self,
+        discr: &Operand<'tcx>,
+        apply_edge_effects: &mut impl SwitchIntEdgeEffects<State<Self::Value>>,
+    ) {
+        // FIXME: The dataflow framework only provides the state if we call `apply()`, which makes
+        // this more inefficient than it has to be.
+        let mut discr_value = None;
+        let mut handled = false;
+        apply_edge_effects.apply(|state, target| {
+            let discr_value = match discr_value {
+                Some(value) => value,
+                None => {
+                    let value = match self.handle_operand(discr, state) {
+                        ValueOrPlace::Value(value) => value,
+                        ValueOrPlace::Place(place) => state.get_idx(place, self.map()),
+                    };
+                    let result = match value {
+                        FlatSet::Top => FlatSet::Top,
+                        FlatSet::Elem(ScalarTy(scalar, _)) => {
+                            let int = scalar.assert_int();
+                            FlatSet::Elem(int.assert_bits(int.size()))
+                        }
+                        FlatSet::Bottom => FlatSet::Bottom,
+                    };
+                    discr_value = Some(result);
+                    result
+                }
+            };
+
+            let FlatSet::Elem(choice) = discr_value else {
+                // Do nothing if we don't know which branch will be taken.
+                return
+            };
+
+            if target.value.map(|n| n == choice).unwrap_or(!handled) {
+                // Branch is taken. Has no effect on state.
+                handled = true;
+            } else {
+                // Branch is not taken.
+                state.mark_unreachable();
+            }
+        })
+    }
+}
+
+#[derive(Clone, PartialEq, Eq)]
+struct ScalarTy<'tcx>(Scalar, Ty<'tcx>);
+
+impl<'tcx> std::fmt::Debug for ScalarTy<'tcx> {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        // This is used for dataflow visualization, so we return something more concise.
+        std::fmt::Display::fmt(&ConstantKind::Val(ConstValue::Scalar(self.0), self.1), f)
+    }
+}
+
+impl<'tcx> ConstAnalysis<'tcx> {
+    pub fn new(tcx: TyCtxt<'tcx>, body: &Body<'tcx>, map: Map) -> Self {
+        let param_env = tcx.param_env(body.source.def_id());
+        Self {
+            map,
+            tcx,
+            ecx: InterpCx::new(tcx, DUMMY_SP, param_env, DummyMachine),
+            param_env: param_env,
+        }
+    }
+
+    fn binary_op(
+        &self,
+        state: &mut State<FlatSet<ScalarTy<'tcx>>>,
+        op: BinOp,
+        left: &Operand<'tcx>,
+        right: &Operand<'tcx>,
+    ) -> (FlatSet<ScalarTy<'tcx>>, FlatSet<bool>) {
+        let left = self.eval_operand(left, state);
+        let right = self.eval_operand(right, state);
+        match (left, right) {
+            (FlatSet::Elem(left), FlatSet::Elem(right)) => {
+                match self.ecx.overflowing_binary_op(op, &left, &right) {
+                    Ok((val, overflow, ty)) => (self.wrap_scalar(val, ty), FlatSet::Elem(overflow)),
+                    _ => (FlatSet::Top, FlatSet::Top),
+                }
+            }
+            (FlatSet::Bottom, _) | (_, FlatSet::Bottom) => (FlatSet::Bottom, FlatSet::Bottom),
+            (_, _) => {
+                // Could attempt some algebraic simplifcations here.
+                (FlatSet::Top, FlatSet::Top)
+            }
+        }
+    }
+
+    fn eval_operand(
+        &self,
+        op: &Operand<'tcx>,
+        state: &mut State<FlatSet<ScalarTy<'tcx>>>,
+    ) -> FlatSet<ImmTy<'tcx>> {
+        let value = match self.handle_operand(op, state) {
+            ValueOrPlace::Value(value) => value,
+            ValueOrPlace::Place(place) => state.get_idx(place, &self.map),
+        };
+        match value {
+            FlatSet::Top => FlatSet::Top,
+            FlatSet::Elem(ScalarTy(scalar, ty)) => self
+                .tcx
+                .layout_of(self.param_env.and(ty))
+                .map(|layout| FlatSet::Elem(ImmTy::from_scalar(scalar, layout)))
+                .unwrap_or(FlatSet::Top),
+            FlatSet::Bottom => FlatSet::Bottom,
+        }
+    }
+
+    fn wrap_scalar(&self, scalar: Scalar, ty: Ty<'tcx>) -> FlatSet<ScalarTy<'tcx>> {
+        FlatSet::Elem(ScalarTy(scalar, ty))
+    }
+
+    fn wrap_immediate(&self, imm: Immediate, ty: Ty<'tcx>) -> FlatSet<ScalarTy<'tcx>> {
+        match imm {
+            Immediate::Scalar(scalar) => self.wrap_scalar(scalar, ty),
+            _ => FlatSet::Top,
+        }
+    }
+
+    fn wrap_immty(&self, val: ImmTy<'tcx>) -> FlatSet<ScalarTy<'tcx>> {
+        self.wrap_immediate(*val, val.layout.ty)
+    }
+}
+
+struct CollectAndPatch<'tcx, 'map> {
+    tcx: TyCtxt<'tcx>,
+    map: &'map Map,
+
+    /// For a given MIR location, this stores the values of the operands used by that location. In
+    /// particular, this is before the effect, such that the operands of `_1 = _1 + _2` are
+    /// properly captured. (This may become UB soon, but it is currently emitted even by safe code.)
+    before_effect: FxHashMap<(Location, Place<'tcx>), ScalarTy<'tcx>>,
+
+    /// Stores the assigned values for assignments where the Rvalue is constant.
+    assignments: FxHashMap<Location, ScalarTy<'tcx>>,
+}
+
+impl<'tcx, 'map> CollectAndPatch<'tcx, 'map> {
+    fn new(tcx: TyCtxt<'tcx>, map: &'map Map) -> Self {
+        Self { tcx, map, before_effect: FxHashMap::default(), assignments: FxHashMap::default() }
+    }
+
+    fn make_operand(&self, scalar: ScalarTy<'tcx>) -> Operand<'tcx> {
+        Operand::Constant(Box::new(Constant {
+            span: DUMMY_SP,
+            user_ty: None,
+            literal: ConstantKind::Val(ConstValue::Scalar(scalar.0), scalar.1),
+        }))
+    }
+}
+
+impl<'mir, 'tcx, 'map> ResultsVisitor<'mir, 'tcx> for CollectAndPatch<'tcx, 'map> {
+    type FlowState = State<FlatSet<ScalarTy<'tcx>>>;
+
+    fn visit_statement_before_primary_effect(
+        &mut self,
+        state: &Self::FlowState,
+        statement: &'mir Statement<'tcx>,
+        location: Location,
+    ) {
+        match &statement.kind {
+            StatementKind::Assign(box (_, rvalue)) => {
+                OperandCollector { state, visitor: self }.visit_rvalue(rvalue, location);
+            }
+            _ => (),
+        }
+    }
+
+    fn visit_statement_after_primary_effect(
+        &mut self,
+        state: &Self::FlowState,
+        statement: &'mir Statement<'tcx>,
+        location: Location,
+    ) {
+        match statement.kind {
+            StatementKind::Assign(box (_, Rvalue::Use(Operand::Constant(_)))) => {
+                // Don't overwrite the assignment if it already uses a constant (to keep the span).
+            }
+            StatementKind::Assign(box (place, _)) => match state.get(place.as_ref(), self.map) {
+                FlatSet::Top => (),
+                FlatSet::Elem(value) => {
+                    self.assignments.insert(location, value);
+                }
+                FlatSet::Bottom => {
+                    // This assignment is either unreachable, or an uninitialized value is assigned.
+                }
+            },
+            _ => (),
+        }
+    }
+
+    fn visit_terminator_before_primary_effect(
+        &mut self,
+        state: &Self::FlowState,
+        terminator: &'mir Terminator<'tcx>,
+        location: Location,
+    ) {
+        OperandCollector { state, visitor: self }.visit_terminator(terminator, location);
+    }
+}
+
+impl<'tcx, 'map> MutVisitor<'tcx> for CollectAndPatch<'tcx, 'map> {
+    fn tcx<'a>(&'a self) -> TyCtxt<'tcx> {
+        self.tcx
+    }
+
+    fn visit_statement(&mut self, statement: &mut Statement<'tcx>, location: Location) {
+        if let Some(value) = self.assignments.get(&location) {
+            match &mut statement.kind {
+                StatementKind::Assign(box (_, rvalue)) => {
+                    *rvalue = Rvalue::Use(self.make_operand(value.clone()));
+                }
+                _ => bug!("found assignment info for non-assign statement"),
+            }
+        } else {
+            self.super_statement(statement, location);
+        }
+    }
+
+    fn visit_operand(&mut self, operand: &mut Operand<'tcx>, location: Location) {
+        match operand {
+            Operand::Copy(place) | Operand::Move(place) => {
+                if let Some(value) = self.before_effect.get(&(location, *place)) {
+                    *operand = self.make_operand(value.clone());
+                }
+            }
+            _ => (),
+        }
+    }
+}
+
+struct OperandCollector<'tcx, 'map, 'a> {
+    state: &'a State<FlatSet<ScalarTy<'tcx>>>,
+    visitor: &'a mut CollectAndPatch<'tcx, 'map>,
+}
+
+impl<'tcx, 'map, 'a> Visitor<'tcx> for OperandCollector<'tcx, 'map, 'a> {
+    fn visit_operand(&mut self, operand: &Operand<'tcx>, location: Location) {
+        match operand {
+            Operand::Copy(place) | Operand::Move(place) => {
+                match self.state.get(place.as_ref(), self.visitor.map) {
+                    FlatSet::Top => (),
+                    FlatSet::Elem(value) => {
+                        self.visitor.before_effect.insert((location, *place), value);
+                    }
+                    FlatSet::Bottom => (),
+                }
+            }
+            _ => (),
+        }
+    }
+}
+
+struct DummyMachine;
+
+impl<'mir, 'tcx> rustc_const_eval::interpret::Machine<'mir, 'tcx> for DummyMachine {
+    rustc_const_eval::interpret::compile_time_machine!(<'mir, 'tcx>);
+    type MemoryKind = !;
+    const PANIC_ON_ALLOC_FAIL: bool = true;
+
+    fn enforce_alignment(_ecx: &InterpCx<'mir, 'tcx, Self>) -> bool {
+        unimplemented!()
+    }
+
+    fn enforce_validity(_ecx: &InterpCx<'mir, 'tcx, Self>) -> bool {
+        unimplemented!()
+    }
+
+    fn find_mir_or_eval_fn(
+        _ecx: &mut InterpCx<'mir, 'tcx, Self>,
+        _instance: ty::Instance<'tcx>,
+        _abi: rustc_target::spec::abi::Abi,
+        _args: &[rustc_const_eval::interpret::OpTy<'tcx, Self::Provenance>],
+        _destination: &rustc_const_eval::interpret::PlaceTy<'tcx, Self::Provenance>,
+        _target: Option<BasicBlock>,
+        _unwind: rustc_const_eval::interpret::StackPopUnwind,
+    ) -> interpret::InterpResult<'tcx, Option<(&'mir Body<'tcx>, ty::Instance<'tcx>)>> {
+        unimplemented!()
+    }
+
+    fn call_intrinsic(
+        _ecx: &mut InterpCx<'mir, 'tcx, Self>,
+        _instance: ty::Instance<'tcx>,
+        _args: &[rustc_const_eval::interpret::OpTy<'tcx, Self::Provenance>],
+        _destination: &rustc_const_eval::interpret::PlaceTy<'tcx, Self::Provenance>,
+        _target: Option<BasicBlock>,
+        _unwind: rustc_const_eval::interpret::StackPopUnwind,
+    ) -> interpret::InterpResult<'tcx> {
+        unimplemented!()
+    }
+
+    fn assert_panic(
+        _ecx: &mut InterpCx<'mir, 'tcx, Self>,
+        _msg: &rustc_middle::mir::AssertMessage<'tcx>,
+        _unwind: Option<BasicBlock>,
+    ) -> interpret::InterpResult<'tcx> {
+        unimplemented!()
+    }
+
+    fn binary_ptr_op(
+        _ecx: &InterpCx<'mir, 'tcx, Self>,
+        _bin_op: BinOp,
+        _left: &rustc_const_eval::interpret::ImmTy<'tcx, Self::Provenance>,
+        _right: &rustc_const_eval::interpret::ImmTy<'tcx, Self::Provenance>,
+    ) -> interpret::InterpResult<'tcx, (interpret::Scalar<Self::Provenance>, bool, Ty<'tcx>)> {
+        throw_unsup!(Unsupported("".into()))
+    }
+
+    fn expose_ptr(
+        _ecx: &mut InterpCx<'mir, 'tcx, Self>,
+        _ptr: interpret::Pointer<Self::Provenance>,
+    ) -> interpret::InterpResult<'tcx> {
+        unimplemented!()
+    }
+
+    fn init_frame_extra(
+        _ecx: &mut InterpCx<'mir, 'tcx, Self>,
+        _frame: rustc_const_eval::interpret::Frame<'mir, 'tcx, Self::Provenance>,
+    ) -> interpret::InterpResult<
+        'tcx,
+        rustc_const_eval::interpret::Frame<'mir, 'tcx, Self::Provenance, Self::FrameExtra>,
+    > {
+        unimplemented!()
+    }
+
+    fn stack<'a>(
+        _ecx: &'a InterpCx<'mir, 'tcx, Self>,
+    ) -> &'a [rustc_const_eval::interpret::Frame<'mir, 'tcx, Self::Provenance, Self::FrameExtra>]
+    {
+        unimplemented!()
+    }
+
+    fn stack_mut<'a>(
+        _ecx: &'a mut InterpCx<'mir, 'tcx, Self>,
+    ) -> &'a mut Vec<
+        rustc_const_eval::interpret::Frame<'mir, 'tcx, Self::Provenance, Self::FrameExtra>,
+    > {
+        unimplemented!()
+    }
+}
diff --git a/compiler/rustc_mir_transform/src/deduce_param_attrs.rs b/compiler/rustc_mir_transform/src/deduce_param_attrs.rs
index 18352fbf675c..28b1c5a48099 100644
--- a/compiler/rustc_mir_transform/src/deduce_param_attrs.rs
+++ b/compiler/rustc_mir_transform/src/deduce_param_attrs.rs
@@ -11,7 +11,6 @@ use rustc_middle::mir::visit::{NonMutatingUseContext, PlaceContext, Visitor};
 use rustc_middle::mir::{Body, Local, Location, Operand, Terminator, TerminatorKind, RETURN_PLACE};
 use rustc_middle::ty::{self, DeducedParamAttrs, ParamEnv, Ty, TyCtxt};
 use rustc_session::config::OptLevel;
-use rustc_span::DUMMY_SP;
 
 /// A visitor that determines which arguments have been mutated. We can't use the mutability field
 /// on LocalDecl for this because it has no meaning post-optimization.
@@ -232,7 +231,7 @@ pub fn deduced_param_attrs<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> &'tcx [Ded
         body.local_decls.iter().skip(1).take(body.arg_count).enumerate().map(
             |(arg_index, local_decl)| DeducedParamAttrs {
                 read_only: !deduce_read_only.mutable_args.contains(arg_index)
-                    && local_decl.ty.is_freeze(tcx.at(DUMMY_SP), ParamEnv::reveal_all()),
+                    && local_decl.ty.is_freeze(tcx, ParamEnv::reveal_all()),
             },
         ),
     );
diff --git a/compiler/rustc_mir_transform/src/lib.rs b/compiler/rustc_mir_transform/src/lib.rs
index 5c411fa56578..692eeddfb985 100644
--- a/compiler/rustc_mir_transform/src/lib.rs
+++ b/compiler/rustc_mir_transform/src/lib.rs
@@ -54,6 +54,7 @@ mod const_goto;
 mod const_prop;
 mod const_prop_lint;
 mod coverage;
+mod dataflow_const_prop;
 mod dead_store_elimination;
 mod deaggregator;
 mod deduce_param_attrs;
@@ -71,7 +72,6 @@ mod inline;
 mod instcombine;
 mod lower_intrinsics;
 mod lower_slice_len;
-mod marker;
 mod match_branches;
 mod multiple_return_terminators;
 mod normalize_array_len;
@@ -289,7 +289,7 @@ fn mir_const<'tcx>(
 
     let mut body = tcx.mir_built(def).steal();
 
-    rustc_middle::mir::dump_mir(tcx, None, "mir_map", &0, &body, |_, _| Ok(()));
+    pass_manager::dump_mir_for_phase_change(tcx, &body);
 
     pm::run_passes(
         tcx,
@@ -303,6 +303,7 @@ fn mir_const<'tcx>(
             &simplify::SimplifyCfg::new("initial"),
             &rustc_peek::SanityCheck, // Just a lint
         ],
+        None,
     );
     tcx.alloc_steal_mir(body)
 }
@@ -342,6 +343,7 @@ fn mir_promoted<'tcx>(
             &simplify::SimplifyCfg::new("promote-consts"),
             &coverage::InstrumentCoverage,
         ],
+        Some(MirPhase::Analysis(AnalysisPhase::Initial)),
     );
 
     let promoted = promote_pass.promoted_fragments.into_inner();
@@ -409,10 +411,8 @@ fn inner_mir_for_ctfe(tcx: TyCtxt<'_>, def: ty::WithOptConstParam<LocalDefId>) -
             pm::run_passes(
                 tcx,
                 &mut body,
-                &[
-                    &const_prop::ConstProp,
-                    &marker::PhaseChange(MirPhase::Runtime(RuntimePhase::Optimized)),
-                ],
+                &[&const_prop::ConstProp],
+                Some(MirPhase::Runtime(RuntimePhase::Optimized)),
             );
         }
     }
@@ -474,6 +474,7 @@ fn run_analysis_to_runtime_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>
                 &remove_uninit_drops::RemoveUninitDrops,
                 &simplify::SimplifyCfg::new("remove-false-edges"),
             ],
+            None,
         );
         check_consts::post_drop_elaboration::check_live_drops(tcx, &body); // FIXME: make this a MIR lint
     }
@@ -498,10 +499,9 @@ fn run_analysis_cleanup_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
         &cleanup_post_borrowck::CleanupNonCodegenStatements,
         &simplify::SimplifyCfg::new("early-opt"),
         &deref_separator::Derefer,
-        &marker::PhaseChange(MirPhase::Analysis(AnalysisPhase::PostCleanup)),
     ];
 
-    pm::run_passes(tcx, body, passes);
+    pm::run_passes(tcx, body, passes, Some(MirPhase::Analysis(AnalysisPhase::PostCleanup)));
 }
 
 /// Returns the sequence of passes that lowers analysis to runtime MIR.
@@ -526,9 +526,8 @@ fn run_runtime_lowering_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
         // CTFE support for aggregates.
         &deaggregator::Deaggregator,
         &Lint(const_prop_lint::ConstProp),
-        &marker::PhaseChange(MirPhase::Runtime(RuntimePhase::Initial)),
     ];
-    pm::run_passes_no_validate(tcx, body, passes);
+    pm::run_passes_no_validate(tcx, body, passes, Some(MirPhase::Runtime(RuntimePhase::Initial)));
 }
 
 /// Returns the sequence of passes that do the initial cleanup of runtime MIR.
@@ -537,10 +536,9 @@ fn run_runtime_cleanup_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
         &elaborate_box_derefs::ElaborateBoxDerefs,
         &lower_intrinsics::LowerIntrinsics,
         &simplify::SimplifyCfg::new("elaborate-drops"),
-        &marker::PhaseChange(MirPhase::Runtime(RuntimePhase::PostCleanup)),
     ];
 
-    pm::run_passes(tcx, body, passes);
+    pm::run_passes(tcx, body, passes, Some(MirPhase::Runtime(RuntimePhase::PostCleanup)));
 }
 
 fn run_optimization_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
@@ -572,6 +570,7 @@ fn run_optimization_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
             //
             // FIXME(#70073): This pass is responsible for both optimization as well as some lints.
             &const_prop::ConstProp,
+            &dataflow_const_prop::DataflowConstProp,
             //
             // Const-prop runs unconditionally, but doesn't mutate the MIR at mir-opt-level=0.
             &const_debuginfo::ConstDebugInfo,
@@ -591,10 +590,10 @@ fn run_optimization_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
             &deduplicate_blocks::DeduplicateBlocks,
             // Some cleanup necessary at least for LLVM and potentially other codegen backends.
             &add_call_guards::CriticalCallEdges,
-            &marker::PhaseChange(MirPhase::Runtime(RuntimePhase::Optimized)),
             // Dump the end result for testing and debugging purposes.
             &dump_mir::Marker("PreCodegen"),
         ],
+        Some(MirPhase::Runtime(RuntimePhase::Optimized)),
     );
 }
 
diff --git a/compiler/rustc_mir_transform/src/marker.rs b/compiler/rustc_mir_transform/src/marker.rs
deleted file mode 100644
index 06819fc1d37d..000000000000
--- a/compiler/rustc_mir_transform/src/marker.rs
+++ /dev/null
@@ -1,20 +0,0 @@
-use std::borrow::Cow;
-
-use crate::MirPass;
-use rustc_middle::mir::{Body, MirPhase};
-use rustc_middle::ty::TyCtxt;
-
-/// Changes the MIR phase without changing the MIR itself.
-pub struct PhaseChange(pub MirPhase);
-
-impl<'tcx> MirPass<'tcx> for PhaseChange {
-    fn phase_change(&self) -> Option<MirPhase> {
-        Some(self.0)
-    }
-
-    fn name(&self) -> Cow<'_, str> {
-        Cow::from(format!("PhaseChange-{:?}", self.0))
-    }
-
-    fn run_pass(&self, _: TyCtxt<'tcx>, _body: &mut Body<'tcx>) {}
-}
diff --git a/compiler/rustc_mir_transform/src/pass_manager.rs b/compiler/rustc_mir_transform/src/pass_manager.rs
index 67dae71468f9..27dbc3e22c97 100644
--- a/compiler/rustc_mir_transform/src/pass_manager.rs
+++ b/compiler/rustc_mir_transform/src/pass_manager.rs
@@ -66,10 +66,6 @@ where
     fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
         self.1.run_pass(tcx, body)
     }
-
-    fn phase_change(&self) -> Option<MirPhase> {
-        self.1.phase_change()
-    }
 }
 
 /// Run the sequence of passes without validating the MIR after each pass. The MIR is still
@@ -78,66 +74,85 @@ pub fn run_passes_no_validate<'tcx>(
     tcx: TyCtxt<'tcx>,
     body: &mut Body<'tcx>,
     passes: &[&dyn MirPass<'tcx>],
+    phase_change: Option<MirPhase>,
 ) {
-    run_passes_inner(tcx, body, passes, false);
+    run_passes_inner(tcx, body, passes, phase_change, false);
 }
 
-pub fn run_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>, passes: &[&dyn MirPass<'tcx>]) {
-    run_passes_inner(tcx, body, passes, true);
+/// The optional `phase_change` is applied after executing all the passes, if present
+pub fn run_passes<'tcx>(
+    tcx: TyCtxt<'tcx>,
+    body: &mut Body<'tcx>,
+    passes: &[&dyn MirPass<'tcx>],
+    phase_change: Option<MirPhase>,
+) {
+    run_passes_inner(tcx, body, passes, phase_change, true);
 }
 
 fn run_passes_inner<'tcx>(
     tcx: TyCtxt<'tcx>,
     body: &mut Body<'tcx>,
     passes: &[&dyn MirPass<'tcx>],
+    phase_change: Option<MirPhase>,
     validate_each: bool,
 ) {
-    let start_phase = body.phase;
-    let mut cnt = 0;
-
-    let validate = validate_each & tcx.sess.opts.unstable_opts.validate_mir;
+    let validate = validate_each & tcx.sess.opts.unstable_opts.validate_mir & !body.should_skip();
     let overridden_passes = &tcx.sess.opts.unstable_opts.mir_enable_passes;
     trace!(?overridden_passes);
 
-    for pass in passes {
-        let name = pass.name();
+    if !body.should_skip() {
+        for pass in passes {
+            let name = pass.name();
 
-        // Gather information about what we should be doing for this pass
-        let overridden =
-            overridden_passes.iter().rev().find(|(s, _)| s == &*name).map(|(_name, polarity)| {
-                trace!(
-                    pass = %name,
-                    "{} as requested by flag",
-                    if *polarity { "Running" } else { "Not running" },
-                );
-                *polarity
-            });
-        let is_enabled = overridden.unwrap_or_else(|| pass.is_enabled(&tcx.sess));
-        let new_phase = pass.phase_change();
-        let dump_enabled = (is_enabled && pass.is_mir_dump_enabled()) || new_phase.is_some();
-        let validate = (validate && is_enabled)
-            || new_phase == Some(MirPhase::Runtime(RuntimePhase::Optimized));
-
-        if dump_enabled {
-            dump_mir(tcx, body, start_phase, &name, cnt, false);
-        }
-        if is_enabled {
-            pass.run_pass(tcx, body);
-        }
-        if dump_enabled {
-            dump_mir(tcx, body, start_phase, &name, cnt, true);
-            cnt += 1;
-        }
-        if let Some(new_phase) = pass.phase_change() {
-            if body.phase >= new_phase {
-                panic!("Invalid MIR phase transition from {:?} to {:?}", body.phase, new_phase);
+            let overridden = overridden_passes.iter().rev().find(|(s, _)| s == &*name).map(
+                |(_name, polarity)| {
+                    trace!(
+                        pass = %name,
+                        "{} as requested by flag",
+                        if *polarity { "Running" } else { "Not running" },
+                    );
+                    *polarity
+                },
+            );
+            if !overridden.unwrap_or_else(|| pass.is_enabled(&tcx.sess)) {
+                continue;
             }
 
-            body.phase = new_phase;
+            let dump_enabled = pass.is_mir_dump_enabled();
+
+            if dump_enabled {
+                dump_mir_for_pass(tcx, body, &name, false);
+            }
+            if validate {
+                validate_body(tcx, body, format!("before pass {}", name));
+            }
+
+            pass.run_pass(tcx, body);
+
+            if dump_enabled {
+                dump_mir_for_pass(tcx, body, &name, true);
+            }
+            if validate {
+                validate_body(tcx, body, format!("after pass {}", name));
+            }
+
+            body.pass_count += 1;
         }
-        if validate {
-            validate_body(tcx, body, format!("after pass {}", name));
+    }
+
+    if let Some(new_phase) = phase_change {
+        if body.phase >= new_phase {
+            panic!("Invalid MIR phase transition from {:?} to {:?}", body.phase, new_phase);
         }
+
+        body.phase = new_phase;
+
+        dump_mir_for_phase_change(tcx, body);
+        if validate || new_phase == MirPhase::Runtime(RuntimePhase::Optimized) {
+            validate_body(tcx, body, format!("after phase change to {}", new_phase));
+        }
+
+        body.pass_count = 1;
     }
 }
 
@@ -145,22 +160,33 @@ pub fn validate_body<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>, when: Strin
     validate::Validator { when, mir_phase: body.phase }.run_pass(tcx, body);
 }
 
-pub fn dump_mir<'tcx>(
+pub fn dump_mir_for_pass<'tcx>(
     tcx: TyCtxt<'tcx>,
     body: &Body<'tcx>,
-    phase: MirPhase,
     pass_name: &str,
-    cnt: usize,
     is_after: bool,
 ) {
-    let phase_index = phase.phase_index();
+    let phase_index = body.phase.phase_index();
 
     mir::dump_mir(
         tcx,
-        Some(&format_args!("{:03}-{:03}", phase_index, cnt)),
+        Some(&format_args!("{:03}-{:03}", phase_index, body.pass_count)),
         pass_name,
         if is_after { &"after" } else { &"before" },
         body,
         |_, _| Ok(()),
     );
 }
+
+pub fn dump_mir_for_phase_change<'tcx>(tcx: TyCtxt<'tcx>, body: &Body<'tcx>) {
+    let phase_index = body.phase.phase_index();
+
+    mir::dump_mir(
+        tcx,
+        Some(&format_args!("{:03}-000", phase_index)),
+        &format!("{}", body.phase),
+        &"after",
+        body,
+        |_, _| Ok(()),
+    )
+}
diff --git a/compiler/rustc_mir_transform/src/required_consts.rs b/compiler/rustc_mir_transform/src/required_consts.rs
index cc75947d9dda..0ea8f2ba93fd 100644
--- a/compiler/rustc_mir_transform/src/required_consts.rs
+++ b/compiler/rustc_mir_transform/src/required_consts.rs
@@ -17,7 +17,7 @@ impl<'tcx> Visitor<'tcx> for RequiredConstsVisitor<'_, 'tcx> {
         let literal = constant.literal;
         match literal {
             ConstantKind::Ty(c) => match c.kind() {
-                ConstKind::Param(_) => {}
+                ConstKind::Param(_) | ConstKind::Error(_) => {}
                 _ => bug!("only ConstKind::Param should be encountered here, got {:#?}", c),
             },
             ConstantKind::Unevaluated(..) => self.required_consts.push(*constant),
diff --git a/compiler/rustc_mir_transform/src/shim.rs b/compiler/rustc_mir_transform/src/shim.rs
index 6ca58ee458c5..a0ff7550faeb 100644
--- a/compiler/rustc_mir_transform/src/shim.rs
+++ b/compiler/rustc_mir_transform/src/shim.rs
@@ -17,7 +17,7 @@ use std::iter;
 
 use crate::util::expand_aggregate;
 use crate::{
-    abort_unwinding_calls, add_call_guards, add_moves_for_packed_drops, deref_separator, marker,
+    abort_unwinding_calls, add_call_guards, add_moves_for_packed_drops, deref_separator,
     pass_manager as pm, remove_noop_landing_pads, simplify,
 };
 use rustc_middle::mir::patch::MirPatch;
@@ -97,8 +97,8 @@ fn make_shim<'tcx>(tcx: TyCtxt<'tcx>, instance: ty::InstanceDef<'tcx>) -> Body<'
             &simplify::SimplifyCfg::new("make_shim"),
             &add_call_guards::CriticalCallEdges,
             &abort_unwinding_calls::AbortUnwindingCalls,
-            &marker::PhaseChange(MirPhase::Runtime(RuntimePhase::Optimized)),
         ],
+        Some(MirPhase::Runtime(RuntimePhase::Optimized)),
     );
 
     debug!("make_shim({:?}) = {:?}", instance, result);
@@ -312,7 +312,7 @@ fn build_clone_shim<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, self_ty: Ty<'tcx>) -
     let param_env = tcx.param_env(def_id);
 
     let mut builder = CloneShimBuilder::new(tcx, def_id, self_ty);
-    let is_copy = self_ty.is_copy_modulo_regions(tcx.at(builder.span), param_env);
+    let is_copy = self_ty.is_copy_modulo_regions(tcx, param_env);
 
     let dest = Place::return_place();
     let src = tcx.mk_place_deref(Place::from(Local::new(1 + 0)));
@@ -569,17 +569,13 @@ impl<'tcx> CloneShimBuilder<'tcx> {
 
 /// Builds a "call" shim for `instance`. The shim calls the function specified by `call_kind`,
 /// first adjusting its first argument according to `rcvr_adjustment`.
+#[instrument(level = "debug", skip(tcx), ret)]
 fn build_call_shim<'tcx>(
     tcx: TyCtxt<'tcx>,
     instance: ty::InstanceDef<'tcx>,
     rcvr_adjustment: Option<Adjustment>,
     call_kind: CallKind<'tcx>,
 ) -> Body<'tcx> {
-    debug!(
-        "build_call_shim(instance={:?}, rcvr_adjustment={:?}, call_kind={:?})",
-        instance, rcvr_adjustment, call_kind
-    );
-
     // `FnPtrShim` contains the fn pointer type that a call shim is being built for - this is used
     // to substitute into the signature of the shim. It is not necessary for users of this
     // MIR body to perform further substitutions (see `InstanceDef::has_polymorphic_mir_body`).
@@ -641,7 +637,7 @@ fn build_call_shim<'tcx>(
 
     let span = tcx.def_span(def_id);
 
-    debug!("build_call_shim: sig={:?}", sig);
+    debug!(?sig);
 
     let mut local_decls = local_decls_for_sig(&sig, span);
     let source_info = SourceInfo::outermost(span);
@@ -845,7 +841,7 @@ pub fn build_adt_ctor(tcx: TyCtxt<'_>, ctor_id: DefId) -> Body<'_> {
         span,
     );
 
-    rustc_middle::mir::dump_mir(tcx, None, "mir_map", &0, &body, |_, _| Ok(()));
+    crate::pass_manager::dump_mir_for_phase_change(tcx, &body);
 
     body
 }
diff --git a/compiler/rustc_monomorphize/src/collector.rs b/compiler/rustc_monomorphize/src/collector.rs
index 5cd7a7f760f5..58ddb807059a 100644
--- a/compiler/rustc_monomorphize/src/collector.rs
+++ b/compiler/rustc_monomorphize/src/collector.rs
@@ -201,7 +201,7 @@ use std::iter;
 use std::ops::Range;
 use std::path::PathBuf;
 
-use crate::errors::{LargeAssignmentsLint, RecursionLimit, RequiresLangItem, TypeLengthLimit};
+use crate::errors::{LargeAssignmentsLint, RecursionLimit, TypeLengthLimit};
 
 #[derive(PartialEq)]
 pub enum MonoItemCollectionMode {
@@ -1067,7 +1067,7 @@ fn find_vtable_types_for_unsizing<'tcx>(
     let ptr_vtable = |inner_source: Ty<'tcx>, inner_target: Ty<'tcx>| {
         let param_env = ty::ParamEnv::reveal_all();
         let type_has_metadata = |ty: Ty<'tcx>| -> bool {
-            if ty.is_sized(tcx.at(DUMMY_SP), param_env) {
+            if ty.is_sized(tcx, param_env) {
                 return false;
             }
             let tail = tcx.struct_tail_erasing_lifetimes(ty, param_env);
@@ -1192,7 +1192,7 @@ struct RootCollector<'a, 'tcx> {
 
 impl<'v> RootCollector<'_, 'v> {
     fn process_item(&mut self, id: hir::ItemId) {
-        match self.tcx.def_kind(id.def_id) {
+        match self.tcx.def_kind(id.owner_id) {
             DefKind::Enum | DefKind::Struct | DefKind::Union => {
                 let item = self.tcx.hir().item(id);
                 match item.kind {
@@ -1203,12 +1203,14 @@ impl<'v> RootCollector<'_, 'v> {
                             if self.mode == MonoItemCollectionMode::Eager {
                                 debug!(
                                     "RootCollector: ADT drop-glue for {}",
-                                    self.tcx.def_path_str(item.def_id.to_def_id())
+                                    self.tcx.def_path_str(item.owner_id.to_def_id())
                                 );
 
-                                let ty =
-                                    Instance::new(item.def_id.to_def_id(), InternalSubsts::empty())
-                                        .ty(self.tcx, ty::ParamEnv::reveal_all());
+                                let ty = Instance::new(
+                                    item.owner_id.to_def_id(),
+                                    InternalSubsts::empty(),
+                                )
+                                .ty(self.tcx, ty::ParamEnv::reveal_all());
                                 visit_drop_use(self.tcx, ty, true, DUMMY_SP, self.output);
                             }
                         }
@@ -1219,23 +1221,23 @@ impl<'v> RootCollector<'_, 'v> {
             DefKind::GlobalAsm => {
                 debug!(
                     "RootCollector: ItemKind::GlobalAsm({})",
-                    self.tcx.def_path_str(id.def_id.to_def_id())
+                    self.tcx.def_path_str(id.owner_id.to_def_id())
                 );
                 self.output.push(dummy_spanned(MonoItem::GlobalAsm(id)));
             }
             DefKind::Static(..) => {
                 debug!(
                     "RootCollector: ItemKind::Static({})",
-                    self.tcx.def_path_str(id.def_id.to_def_id())
+                    self.tcx.def_path_str(id.owner_id.to_def_id())
                 );
-                self.output.push(dummy_spanned(MonoItem::Static(id.def_id.to_def_id())));
+                self.output.push(dummy_spanned(MonoItem::Static(id.owner_id.to_def_id())));
             }
             DefKind::Const => {
                 // const items only generate mono items if they are
                 // actually used somewhere. Just declaring them is insufficient.
 
                 // but even just declaring them must collect the items they refer to
-                if let Ok(val) = self.tcx.const_eval_poly(id.def_id.to_def_id()) {
+                if let Ok(val) = self.tcx.const_eval_poly(id.owner_id.to_def_id()) {
                     collect_const_value(self.tcx, val, &mut self.output);
                 }
             }
@@ -1246,15 +1248,15 @@ impl<'v> RootCollector<'_, 'v> {
                 }
             }
             DefKind::Fn => {
-                self.push_if_root(id.def_id.def_id);
+                self.push_if_root(id.owner_id.def_id);
             }
             _ => {}
         }
     }
 
     fn process_impl_item(&mut self, id: hir::ImplItemId) {
-        if matches!(self.tcx.def_kind(id.def_id), DefKind::AssocFn) {
-            self.push_if_root(id.def_id.def_id);
+        if matches!(self.tcx.def_kind(id.owner_id), DefKind::AssocFn) {
+            self.push_if_root(id.owner_id.def_id);
         }
     }
 
@@ -1296,14 +1298,7 @@ impl<'v> RootCollector<'_, 'v> {
             return;
         };
 
-        let start_def_id = match self.tcx.lang_items().require(LangItem::Start) {
-            Ok(s) => s,
-            Err(lang_item_err) => {
-                self.tcx
-                    .sess
-                    .emit_fatal(RequiresLangItem { lang_item: lang_item_err.0.name().to_string() });
-            }
-        };
+        let start_def_id = self.tcx.require_lang_item(LangItem::Start, None);
         let main_ret_ty = self.tcx.fn_sig(main_def_id).output();
 
         // Given that `main()` has no arguments,
@@ -1341,6 +1336,10 @@ fn create_mono_items_for_default_impls<'tcx>(
 ) {
     match item.kind {
         hir::ItemKind::Impl(ref impl_) => {
+            if matches!(impl_.polarity, hir::ImplPolarity::Negative(_)) {
+                return;
+            }
+
             for param in impl_.generics.params {
                 match param.kind {
                     hir::GenericParamKind::Lifetime { .. } => {}
@@ -1352,13 +1351,13 @@ fn create_mono_items_for_default_impls<'tcx>(
 
             debug!(
                 "create_mono_items_for_default_impls(item={})",
-                tcx.def_path_str(item.def_id.to_def_id())
+                tcx.def_path_str(item.owner_id.to_def_id())
             );
 
-            if let Some(trait_ref) = tcx.impl_trait_ref(item.def_id) {
+            if let Some(trait_ref) = tcx.impl_trait_ref(item.owner_id) {
                 let param_env = ty::ParamEnv::reveal_all();
                 let trait_ref = tcx.normalize_erasing_regions(param_env, trait_ref);
-                let overridden_methods = tcx.impl_item_implementor_ids(item.def_id);
+                let overridden_methods = tcx.impl_item_implementor_ids(item.owner_id);
                 for method in tcx.provided_trait_methods(trait_ref.def_id) {
                     if overridden_methods.contains_key(&method.def_id) {
                         continue;
diff --git a/compiler/rustc_monomorphize/src/errors.rs b/compiler/rustc_monomorphize/src/errors.rs
index ce097b8d846a..f1ca72de8dbe 100644
--- a/compiler/rustc_monomorphize/src/errors.rs
+++ b/compiler/rustc_monomorphize/src/errors.rs
@@ -32,12 +32,6 @@ pub struct TypeLengthLimit {
     pub type_length: usize,
 }
 
-#[derive(Diagnostic)]
-#[diag(monomorphize_requires_lang_item)]
-pub struct RequiresLangItem {
-    pub lang_item: String,
-}
-
 pub struct UnusedGenericParams {
     pub span: Span,
     pub param_spans: Vec<Span>,
@@ -45,6 +39,7 @@ pub struct UnusedGenericParams {
 }
 
 impl IntoDiagnostic<'_> for UnusedGenericParams {
+    #[track_caller]
     fn into_diagnostic(
         self,
         handler: &'_ rustc_errors::Handler,
diff --git a/compiler/rustc_monomorphize/src/partitioning/default.rs b/compiler/rustc_monomorphize/src/partitioning/default.rs
index 15276569c32f..29009c48050e 100644
--- a/compiler/rustc_monomorphize/src/partitioning/default.rs
+++ b/compiler/rustc_monomorphize/src/partitioning/default.rs
@@ -319,7 +319,7 @@ fn characteristic_def_id_of_mono_item<'tcx>(
             Some(def_id)
         }
         MonoItem::Static(def_id) => Some(def_id),
-        MonoItem::GlobalAsm(item_id) => Some(item_id.def_id.to_def_id()),
+        MonoItem::GlobalAsm(item_id) => Some(item_id.owner_id.to_def_id()),
     }
 }
 
@@ -411,9 +411,9 @@ fn mono_item_visibility<'tcx>(
             };
         }
         MonoItem::GlobalAsm(item_id) => {
-            return if tcx.is_reachable_non_generic(item_id.def_id) {
+            return if tcx.is_reachable_non_generic(item_id.owner_id) {
                 *can_be_internalized = false;
-                default_visibility(tcx, item_id.def_id.to_def_id(), false)
+                default_visibility(tcx, item_id.owner_id.to_def_id(), false)
             } else {
                 Visibility::Hidden
             };
diff --git a/compiler/rustc_parse/src/errors.rs b/compiler/rustc_parse/src/errors.rs
index 9b177c5189bf..2b17cea97949 100644
--- a/compiler/rustc_parse/src/errors.rs
+++ b/compiler/rustc_parse/src/errors.rs
@@ -64,7 +64,7 @@ pub(crate) struct BadQPathStage2 {
 #[diag(parser_incorrect_semicolon)]
 pub(crate) struct IncorrectSemicolon<'a> {
     #[primary_span]
-    #[suggestion_short(code = "", applicability = "machine-applicable")]
+    #[suggestion(style = "short", code = "", applicability = "machine-applicable")]
     pub span: Span,
     #[help]
     pub opt_help: Option<()>,
@@ -136,7 +136,12 @@ pub(crate) struct InvalidComparisonOperator {
 
 #[derive(Subdiagnostic)]
 pub(crate) enum InvalidComparisonOperatorSub {
-    #[suggestion_short(use_instead, applicability = "machine-applicable", code = "{correct}")]
+    #[suggestion(
+        use_instead,
+        style = "short",
+        applicability = "machine-applicable",
+        code = "{correct}"
+    )]
     Correctable {
         #[primary_span]
         span: Span,
@@ -160,14 +165,16 @@ pub(crate) struct InvalidLogicalOperator {
 
 #[derive(Subdiagnostic)]
 pub(crate) enum InvalidLogicalOperatorSub {
-    #[suggestion_short(
+    #[suggestion(
         use_amp_amp_for_conjunction,
+        style = "short",
         applicability = "machine-applicable",
         code = "&&"
     )]
     Conjunction(#[primary_span] Span),
-    #[suggestion_short(
+    #[suggestion(
         use_pipe_pipe_for_disjunction,
+        style = "short",
         applicability = "machine-applicable",
         code = "||"
     )]
@@ -178,7 +185,7 @@ pub(crate) enum InvalidLogicalOperatorSub {
 #[diag(parser_tilde_is_not_unary_operator)]
 pub(crate) struct TildeAsUnaryOperator(
     #[primary_span]
-    #[suggestion_short(applicability = "machine-applicable", code = "!")]
+    #[suggestion(style = "short", applicability = "machine-applicable", code = "!")]
     pub Span,
 );
 
@@ -194,22 +201,25 @@ pub(crate) struct NotAsNegationOperator {
 
 #[derive(Subdiagnostic)]
 pub enum NotAsNegationOperatorSub {
-    #[suggestion_short(
+    #[suggestion(
         parser_unexpected_token_after_not_default,
+        style = "short",
         applicability = "machine-applicable",
         code = "!"
     )]
     SuggestNotDefault(#[primary_span] Span),
 
-    #[suggestion_short(
+    #[suggestion(
         parser_unexpected_token_after_not_bitwise,
+        style = "short",
         applicability = "machine-applicable",
         code = "!"
     )]
     SuggestNotBitwise(#[primary_span] Span),
 
-    #[suggestion_short(
+    #[suggestion(
         parser_unexpected_token_after_not_logical,
+        style = "short",
         applicability = "machine-applicable",
         code = "!"
     )]
@@ -249,7 +259,7 @@ pub(crate) struct UnexpectedTokenAfterLabel {
     #[primary_span]
     #[label(parser_unexpected_token_after_label)]
     pub span: Span,
-    #[suggestion_verbose(suggestion_remove_label, code = "")]
+    #[suggestion(suggestion_remove_label, style = "verbose", code = "")]
     pub remove_label: Option<Span>,
     #[subdiagnostic]
     pub enclose_in_block: Option<UnexpectedTokenAfterLabelSugg>,
@@ -272,7 +282,7 @@ pub(crate) struct RequireColonAfterLabeledExpression {
     pub span: Span,
     #[label]
     pub label: Span,
-    #[suggestion_short(applicability = "machine-applicable", code = ": ")]
+    #[suggestion(style = "short", applicability = "machine-applicable", code = ": ")]
     pub label_end: Span,
 }
 
@@ -354,10 +364,19 @@ pub(crate) struct IntLiteralTooLarge {
 pub(crate) struct MissingSemicolonBeforeArray {
     #[primary_span]
     pub open_delim: Span,
-    #[suggestion_verbose(applicability = "maybe-incorrect", code = ";")]
+    #[suggestion(style = "verbose", applicability = "maybe-incorrect", code = ";")]
     pub semicolon: Span,
 }
 
+#[derive(Diagnostic)]
+#[diag(parser_expect_dotdot_not_dotdotdot)]
+pub(crate) struct MissingDotDot {
+    #[primary_span]
+    pub token_span: Span,
+    #[suggestion(applicability = "maybe-incorrect", code = "..", style = "verbose")]
+    pub sugg_span: Span,
+}
+
 #[derive(Diagnostic)]
 #[diag(parser_invalid_block_macro_segment)]
 pub(crate) struct InvalidBlockMacroSegment {
@@ -401,6 +420,15 @@ pub(crate) struct ExpectedExpressionFoundLet {
     pub span: Span,
 }
 
+#[derive(Diagnostic)]
+#[diag(parser_expect_eq_instead_of_eqeq)]
+pub(crate) struct ExpectedEqForLetExpr {
+    #[primary_span]
+    pub span: Span,
+    #[suggestion(applicability = "maybe-incorrect", code = "=", style = "verbose")]
+    pub sugg_span: Span,
+}
+
 #[derive(Diagnostic)]
 #[diag(parser_expected_else_block)]
 pub(crate) struct ExpectedElseBlock {
@@ -442,9 +470,9 @@ pub(crate) struct MissingInInForLoop {
 #[derive(Subdiagnostic)]
 pub(crate) enum MissingInInForLoopSub {
     // Has been misleading, at least in the past (closed Issue #48492), thus maybe-incorrect
-    #[suggestion_short(use_in_not_of, applicability = "maybe-incorrect", code = "in")]
+    #[suggestion(use_in_not_of, style = "short", applicability = "maybe-incorrect", code = "in")]
     InNotOf(#[primary_span] Span),
-    #[suggestion_short(add_in, applicability = "maybe-incorrect", code = " in ")]
+    #[suggestion(add_in, style = "short", applicability = "maybe-incorrect", code = " in ")]
     AddIn(#[primary_span] Span),
 }
 
@@ -470,7 +498,7 @@ pub(crate) struct CatchAfterTry {
 pub(crate) struct CommaAfterBaseStruct {
     #[primary_span]
     pub span: Span,
-    #[suggestion_short(applicability = "machine-applicable", code = "")]
+    #[suggestion(style = "short", applicability = "machine-applicable", code = "")]
     pub comma: Span,
 }
 
@@ -512,7 +540,7 @@ pub(crate) struct RemoveLet {
 #[diag(parser_use_eq_instead)]
 pub(crate) struct UseEqInstead {
     #[primary_span]
-    #[suggestion_short(applicability = "machine-applicable", code = "=")]
+    #[suggestion(style = "short", applicability = "machine-applicable", code = "=")]
     pub span: Span,
 }
 
@@ -520,7 +548,7 @@ pub(crate) struct UseEqInstead {
 #[diag(parser_use_empty_block_not_semi)]
 pub(crate) struct UseEmptyBlockNotSemi {
     #[primary_span]
-    #[suggestion_hidden(applicability = "machine-applicable", code = "{{}}")]
+    #[suggestion(style = "hidden", applicability = "machine-applicable", code = "{{}}")]
     pub span: Span,
 }
 
@@ -576,7 +604,12 @@ pub(crate) struct LeadingPlusNotSupported {
     #[primary_span]
     #[label]
     pub span: Span,
-    #[suggestion_verbose(suggestion_remove_plus, code = "", applicability = "machine-applicable")]
+    #[suggestion(
+        suggestion_remove_plus,
+        style = "verbose",
+        code = "",
+        applicability = "machine-applicable"
+    )]
     pub remove_plus: Option<Span>,
     #[subdiagnostic]
     pub add_parentheses: Option<ExprParenthesesNeeded>,
@@ -843,7 +876,7 @@ pub(crate) struct InvalidCurlyInLetElse {
 #[help]
 pub(crate) struct CompoundAssignmentExpressionInLet {
     #[primary_span]
-    #[suggestion_short(code = "=", applicability = "maybe-incorrect")]
+    #[suggestion(style = "short", code = "=", applicability = "maybe-incorrect")]
     pub span: Span,
 }
 
@@ -864,8 +897,9 @@ pub(crate) struct InvalidMetaItem {
 }
 
 #[derive(Subdiagnostic)]
-#[suggestion_verbose(
+#[suggestion(
     parser_sugg_escape_to_use_as_identifier,
+    style = "verbose",
     applicability = "maybe-incorrect",
     code = "r#"
 )]
@@ -918,6 +952,7 @@ pub(crate) struct ExpectedIdentifier {
 }
 
 impl<'a, G: EmissionGuarantee> IntoDiagnostic<'a, G> for ExpectedIdentifier {
+    #[track_caller]
     fn into_diagnostic(
         self,
         handler: &'a rustc_errors::Handler,
@@ -963,6 +998,7 @@ pub(crate) struct ExpectedSemi {
 }
 
 impl<'a, G: EmissionGuarantee> IntoDiagnostic<'a, G> for ExpectedSemi {
+    #[track_caller]
     fn into_diagnostic(
         self,
         handler: &'a rustc_errors::Handler,
@@ -1003,7 +1039,12 @@ pub(crate) enum ExpectedSemiSugg {
         applicability = "machine-applicable"
     )]
     ChangeToSemi(#[primary_span] Span),
-    #[suggestion_short(parser_sugg_add_semi, code = ";", applicability = "machine-applicable")]
+    #[suggestion(
+        parser_sugg_add_semi,
+        style = "short",
+        code = ";",
+        applicability = "machine-applicable"
+    )]
     AddSemi(#[primary_span] Span),
 }
 
@@ -1057,8 +1098,9 @@ pub(crate) struct GenericParamsWithoutAngleBracketsSugg {
 pub(crate) struct ComparisonOperatorsCannotBeChained {
     #[primary_span]
     pub span: Vec<Span>,
-    #[suggestion_verbose(
+    #[suggestion(
         parser_sugg_turbofish_syntax,
+        style = "verbose",
         code = "::",
         applicability = "maybe-incorrect"
     )]
@@ -1072,8 +1114,9 @@ pub(crate) struct ComparisonOperatorsCannotBeChained {
 
 #[derive(Subdiagnostic)]
 pub(crate) enum ComparisonOperatorsCannotBeChainedSugg {
-    #[suggestion_verbose(
+    #[suggestion(
         sugg_split_comparison,
+        style = "verbose",
         code = " && {middle_term}",
         applicability = "maybe-incorrect"
     )]
@@ -1122,10 +1165,12 @@ pub(crate) struct ParenthesesInForHead {
 #[derive(Subdiagnostic)]
 #[multipart_suggestion(suggestion, applicability = "machine-applicable")]
 pub(crate) struct ParenthesesInForHeadSugg {
-    #[suggestion_part(code = "")]
+    #[suggestion_part(code = "{left_snippet}")]
     pub left: Span,
-    #[suggestion_part(code = "")]
+    pub left_snippet: String,
+    #[suggestion_part(code = "{right_snippet}")]
     pub right: Span,
+    pub right_snippet: String,
 }
 
 #[derive(Diagnostic)]
@@ -1160,6 +1205,14 @@ pub(crate) struct SelfParamNotFirst {
     pub span: Span,
 }
 
+#[derive(Diagnostic)]
+#[diag(parser_invalid_identifier_with_leading_number)]
+pub(crate) struct InvalidIdentiferStartsWithNumber {
+    #[primary_span]
+    #[label]
+    pub span: Span,
+}
+
 #[derive(Diagnostic)]
 #[diag(parser_const_generic_without_braces)]
 pub(crate) struct ConstGenericWithoutBraces {
@@ -1215,7 +1268,7 @@ pub(crate) enum UnexpectedConstParamDeclarationSugg {
 pub(crate) struct UnexpectedConstInGenericParam {
     #[primary_span]
     pub span: Span,
-    #[suggestion_verbose(code = "", applicability = "maybe-incorrect")]
+    #[suggestion(style = "verbose", code = "", applicability = "maybe-incorrect")]
     pub to_remove: Option<Span>,
 }
 
@@ -1223,7 +1276,7 @@ pub(crate) struct UnexpectedConstInGenericParam {
 #[diag(parser_async_move_order_incorrect)]
 pub(crate) struct AsyncMoveOrderIncorrect {
     #[primary_span]
-    #[suggestion_verbose(code = "async move", applicability = "maybe-incorrect")]
+    #[suggestion(style = "verbose", code = "async move", applicability = "maybe-incorrect")]
     pub span: Span,
 }
 
@@ -1235,3 +1288,24 @@ pub(crate) struct DoubleColonInBound {
     #[suggestion(code = ": ", applicability = "machine-applicable")]
     pub between: Span,
 }
+
+#[derive(Diagnostic)]
+#[diag(parser_fn_ptr_with_generics)]
+pub(crate) struct FnPtrWithGenerics {
+    #[primary_span]
+    pub span: Span,
+    #[subdiagnostic]
+    pub sugg: Option<FnPtrWithGenericsSugg>,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion(suggestion, applicability = "maybe-incorrect")]
+pub(crate) struct FnPtrWithGenericsSugg {
+    #[suggestion_part(code = "{snippet}")]
+    pub left: Span,
+    pub snippet: String,
+    #[suggestion_part(code = "")]
+    pub right: Span,
+    pub arity: usize,
+    pub for_param_list_exists: bool,
+}
diff --git a/compiler/rustc_parse/src/lexer/mod.rs b/compiler/rustc_parse/src/lexer/mod.rs
index 462bce16ad71..645262bd2f1d 100644
--- a/compiler/rustc_parse/src/lexer/mod.rs
+++ b/compiler/rustc_parse/src/lexer/mod.rs
@@ -175,20 +175,10 @@ impl<'a> StringReader<'a> {
                         if string == "_" {
                             self.sess
                                 .span_diagnostic
-                                .struct_span_warn(
+                                .struct_span_err(
                                     self.mk_sp(suffix_start, self.pos),
                                     "underscore literal suffix is not allowed",
                                 )
-                                .warn(
-                                    "this was previously accepted by the compiler but is \
-                                       being phased out; it will become a hard error in \
-                                       a future release!",
-                                )
-                                .note(
-                                    "see issue #42326 \
-                                     <https://github.com/rust-lang/rust/issues/42326> \
-                                     for more information",
-                                )
                                 .emit();
                             None
                         } else {
@@ -363,55 +353,55 @@ impl<'a> StringReader<'a> {
     fn cook_lexer_literal(
         &self,
         start: BytePos,
-        suffix_start: BytePos,
+        end: BytePos,
         kind: rustc_lexer::LiteralKind,
     ) -> (token::LitKind, Symbol) {
-        // prefix means `"` or `br"` or `r###"`, ...
-        let (lit_kind, mode, prefix_len, postfix_len) = match kind {
+        match kind {
             rustc_lexer::LiteralKind::Char { terminated } => {
                 if !terminated {
                     self.sess.span_diagnostic.span_fatal_with_code(
-                        self.mk_sp(start, suffix_start),
+                        self.mk_sp(start, end),
                         "unterminated character literal",
                         error_code!(E0762),
                     )
                 }
-                (token::Char, Mode::Char, 1, 1) // ' '
+                self.cook_quoted(token::Char, Mode::Char, start, end, 1, 1) // ' '
             }
             rustc_lexer::LiteralKind::Byte { terminated } => {
                 if !terminated {
                     self.sess.span_diagnostic.span_fatal_with_code(
-                        self.mk_sp(start + BytePos(1), suffix_start),
+                        self.mk_sp(start + BytePos(1), end),
                         "unterminated byte constant",
                         error_code!(E0763),
                     )
                 }
-                (token::Byte, Mode::Byte, 2, 1) // b' '
+                self.cook_quoted(token::Byte, Mode::Byte, start, end, 2, 1) // b' '
             }
             rustc_lexer::LiteralKind::Str { terminated } => {
                 if !terminated {
                     self.sess.span_diagnostic.span_fatal_with_code(
-                        self.mk_sp(start, suffix_start),
+                        self.mk_sp(start, end),
                         "unterminated double quote string",
                         error_code!(E0765),
                     )
                 }
-                (token::Str, Mode::Str, 1, 1) // " "
+                self.cook_quoted(token::Str, Mode::Str, start, end, 1, 1) // " "
             }
             rustc_lexer::LiteralKind::ByteStr { terminated } => {
                 if !terminated {
                     self.sess.span_diagnostic.span_fatal_with_code(
-                        self.mk_sp(start + BytePos(1), suffix_start),
+                        self.mk_sp(start + BytePos(1), end),
                         "unterminated double quote byte string",
                         error_code!(E0766),
                     )
                 }
-                (token::ByteStr, Mode::ByteStr, 2, 1) // b" "
+                self.cook_quoted(token::ByteStr, Mode::ByteStr, start, end, 2, 1) // b" "
             }
             rustc_lexer::LiteralKind::RawStr { n_hashes } => {
                 if let Some(n_hashes) = n_hashes {
                     let n = u32::from(n_hashes);
-                    (token::StrRaw(n_hashes), Mode::RawStr, 2 + n, 1 + n) // r##" "##
+                    let kind = token::StrRaw(n_hashes);
+                    self.cook_quoted(kind, Mode::RawStr, start, end, 2 + n, 1 + n) // r##" "##
                 } else {
                     self.report_raw_str_error(start, 1);
                 }
@@ -419,56 +409,59 @@ impl<'a> StringReader<'a> {
             rustc_lexer::LiteralKind::RawByteStr { n_hashes } => {
                 if let Some(n_hashes) = n_hashes {
                     let n = u32::from(n_hashes);
-                    (token::ByteStrRaw(n_hashes), Mode::RawByteStr, 3 + n, 1 + n) // br##" "##
+                    let kind = token::ByteStrRaw(n_hashes);
+                    self.cook_quoted(kind, Mode::RawByteStr, start, end, 3 + n, 1 + n) // br##" "##
                 } else {
                     self.report_raw_str_error(start, 2);
                 }
             }
             rustc_lexer::LiteralKind::Int { base, empty_int } => {
-                return if empty_int {
+                if empty_int {
                     self.sess
                         .span_diagnostic
                         .struct_span_err_with_code(
-                            self.mk_sp(start, suffix_start),
+                            self.mk_sp(start, end),
                             "no valid digits found for number",
                             error_code!(E0768),
                         )
                         .emit();
                     (token::Integer, sym::integer(0))
                 } else {
-                    self.validate_int_literal(base, start, suffix_start);
-                    (token::Integer, self.symbol_from_to(start, suffix_start))
-                };
+                    if matches!(base, Base::Binary | Base::Octal) {
+                        let base = base as u32;
+                        let s = self.str_from_to(start + BytePos(2), end);
+                        for (idx, c) in s.char_indices() {
+                            if c != '_' && c.to_digit(base).is_none() {
+                                self.err_span_(
+                                    start + BytePos::from_usize(2 + idx),
+                                    start + BytePos::from_usize(2 + idx + c.len_utf8()),
+                                    &format!("invalid digit for a base {} literal", base),
+                                );
+                            }
+                        }
+                    }
+                    (token::Integer, self.symbol_from_to(start, end))
+                }
             }
             rustc_lexer::LiteralKind::Float { base, empty_exponent } => {
                 if empty_exponent {
                     self.err_span_(start, self.pos, "expected at least one digit in exponent");
                 }
-
                 match base {
-                    Base::Hexadecimal => self.err_span_(
-                        start,
-                        suffix_start,
-                        "hexadecimal float literal is not supported",
-                    ),
+                    Base::Hexadecimal => {
+                        self.err_span_(start, end, "hexadecimal float literal is not supported")
+                    }
                     Base::Octal => {
-                        self.err_span_(start, suffix_start, "octal float literal is not supported")
+                        self.err_span_(start, end, "octal float literal is not supported")
                     }
                     Base::Binary => {
-                        self.err_span_(start, suffix_start, "binary float literal is not supported")
+                        self.err_span_(start, end, "binary float literal is not supported")
                     }
-                    _ => (),
+                    _ => {}
                 }
-
-                let id = self.symbol_from_to(start, suffix_start);
-                return (token::Float, id);
+                (token::Float, self.symbol_from_to(start, end))
             }
-        };
-        let content_start = start + BytePos(prefix_len);
-        let content_end = suffix_start - BytePos(postfix_len);
-        let id = self.symbol_from_to(content_start, content_end);
-        self.validate_literal_escape(mode, content_start, content_end, prefix_len, postfix_len);
-        (lit_kind, id)
+        }
     }
 
     #[inline]
@@ -659,20 +652,22 @@ impl<'a> StringReader<'a> {
         )
     }
 
-    fn validate_literal_escape(
+    fn cook_quoted(
         &self,
+        kind: token::LitKind,
         mode: Mode,
-        content_start: BytePos,
-        content_end: BytePos,
+        start: BytePos,
+        end: BytePos,
         prefix_len: u32,
         postfix_len: u32,
-    ) {
+    ) -> (token::LitKind, Symbol) {
+        let content_start = start + BytePos(prefix_len);
+        let content_end = end - BytePos(postfix_len);
         let lit_content = self.str_from_to(content_start, content_end);
         unescape::unescape_literal(lit_content, mode, &mut |range, result| {
             // Here we only check for errors. The actual unescaping is done later.
             if let Err(err) = result {
-                let span_with_quotes = self
-                    .mk_sp(content_start - BytePos(prefix_len), content_end + BytePos(postfix_len));
+                let span_with_quotes = self.mk_sp(start, end);
                 let (start, end) = (range.start as u32, range.end as u32);
                 let lo = content_start + BytePos(start);
                 let hi = lo + BytePos(end - start);
@@ -688,23 +683,7 @@ impl<'a> StringReader<'a> {
                 );
             }
         });
-    }
-
-    fn validate_int_literal(&self, base: Base, content_start: BytePos, content_end: BytePos) {
-        let base = match base {
-            Base::Binary => 2,
-            Base::Octal => 8,
-            _ => return,
-        };
-        let s = self.str_from_to(content_start + BytePos(2), content_end);
-        for (idx, c) in s.char_indices() {
-            let idx = idx as u32;
-            if c != '_' && c.to_digit(base).is_none() {
-                let lo = content_start + BytePos(2 + idx);
-                let hi = content_start + BytePos(2 + idx + c.len_utf8() as u32);
-                self.err_span_(lo, hi, &format!("invalid digit for a base {} literal", base));
-            }
-        }
+        (kind, Symbol::intern(lit_content))
     }
 }
 
diff --git a/compiler/rustc_parse/src/lexer/unescape_error_reporting.rs b/compiler/rustc_parse/src/lexer/unescape_error_reporting.rs
index f075de714267..6373f5b4fd6f 100644
--- a/compiler/rustc_parse/src/lexer/unescape_error_reporting.rs
+++ b/compiler/rustc_parse/src/lexer/unescape_error_reporting.rs
@@ -108,7 +108,7 @@ pub(crate) fn emit_unescape_error(
             }
 
             if !has_help {
-                let (prefix, msg) = if mode.is_bytes() {
+                let (prefix, msg) = if mode.is_byte() {
                     ("b", "if you meant to write a byte string literal, use double quotes")
                 } else {
                     ("", "if you meant to write a `str` literal, use double quotes")
@@ -142,7 +142,7 @@ pub(crate) fn emit_unescape_error(
         EscapeError::EscapeOnlyChar => {
             let (c, char_span) = last_char();
 
-            let msg = if mode.is_bytes() {
+            let msg = if mode.is_byte() {
                 "byte constant must be escaped"
             } else {
                 "character constant must be escaped"
@@ -182,11 +182,11 @@ pub(crate) fn emit_unescape_error(
             let (c, span) = last_char();
 
             let label =
-                if mode.is_bytes() { "unknown byte escape" } else { "unknown character escape" };
+                if mode.is_byte() { "unknown byte escape" } else { "unknown character escape" };
             let ec = escaped_char(c);
             let mut diag = handler.struct_span_err(span, &format!("{}: `{}`", label, ec));
             diag.span_label(span, label);
-            if c == '{' || c == '}' && !mode.is_bytes() {
+            if c == '{' || c == '}' && !mode.is_byte() {
                 diag.help(
                     "if used in a formatting string, curly braces are escaped with `{{` and `}}`",
                 );
@@ -196,7 +196,7 @@ pub(crate) fn emit_unescape_error(
                      version control settings",
                 );
             } else {
-                if !mode.is_bytes() {
+                if !mode.is_byte() {
                     diag.span_suggestion(
                         span_with_quotes,
                         "if you meant to write a literal backslash (perhaps escaping in a regular expression), consider a raw string literal",
@@ -231,16 +231,23 @@ pub(crate) fn emit_unescape_error(
                 .emit();
         }
         EscapeError::NonAsciiCharInByte => {
-            assert!(mode.is_bytes());
             let (c, span) = last_char();
-            let mut err = handler.struct_span_err(span, "non-ASCII character in byte constant");
+            let desc = match mode {
+                Mode::Byte => "byte literal",
+                Mode::ByteStr => "byte string literal",
+                Mode::RawByteStr => "raw byte string literal",
+                _ => panic!("non-is_byte literal paired with NonAsciiCharInByte"),
+            };
+            let mut err = handler.struct_span_err(span, format!("non-ASCII character in {}", desc));
             let postfix = if unicode_width::UnicodeWidthChar::width(c).unwrap_or(1) == 0 {
                 format!(" but is {:?}", c)
             } else {
                 String::new()
             };
-            err.span_label(span, &format!("byte constant must be ASCII{}", postfix));
-            if (c as u32) <= 0xFF {
+            err.span_label(span, &format!("must be ASCII{}", postfix));
+            // Note: the \\xHH suggestions are not given for raw byte string
+            // literals, because they are araw and so cannot use any escapes.
+            if (c as u32) <= 0xFF && mode != Mode::RawByteStr {
                 err.span_suggestion(
                     span,
                     &format!(
@@ -250,9 +257,9 @@ pub(crate) fn emit_unescape_error(
                     format!("\\x{:X}", c as u32),
                     Applicability::MaybeIncorrect,
                 );
-            } else if matches!(mode, Mode::Byte) {
+            } else if mode == Mode::Byte {
                 err.span_label(span, "this multibyte character does not fit into a single byte");
-            } else if matches!(mode, Mode::ByteStr) {
+            } else if mode != Mode::RawByteStr {
                 let mut utf8 = String::new();
                 utf8.push(c);
                 err.span_suggestion(
@@ -270,19 +277,6 @@ pub(crate) fn emit_unescape_error(
             }
             err.emit();
         }
-        EscapeError::NonAsciiCharInByteString => {
-            assert!(mode.is_bytes());
-            let (c, span) = last_char();
-            let postfix = if unicode_width::UnicodeWidthChar::width(c).unwrap_or(1) == 0 {
-                format!(" but is {:?}", c)
-            } else {
-                String::new()
-            };
-            handler
-                .struct_span_err(span, "raw byte string must be ASCII")
-                .span_label(span, &format!("must be ASCII{}", postfix))
-                .emit();
-        }
         EscapeError::OutOfRangeHexEscape => {
             handler
                 .struct_span_err(span, "out of range hex escape")
diff --git a/compiler/rustc_parse/src/lib.rs b/compiler/rustc_parse/src/lib.rs
index 3dcadb4c9115..c78479b098ba 100644
--- a/compiler/rustc_parse/src/lib.rs
+++ b/compiler/rustc_parse/src/lib.rs
@@ -3,6 +3,7 @@
 #![feature(array_windows)]
 #![feature(box_patterns)]
 #![feature(if_let_guard)]
+#![feature(iter_intersperse)]
 #![feature(let_chains)]
 #![feature(never_type)]
 #![feature(rustc_attrs)]
diff --git a/compiler/rustc_parse/src/parser/attr_wrapper.rs b/compiler/rustc_parse/src/parser/attr_wrapper.rs
index 81c051b8f35e..c8160548763c 100644
--- a/compiler/rustc_parse/src/parser/attr_wrapper.rs
+++ b/compiler/rustc_parse/src/parser/attr_wrapper.rs
@@ -5,7 +5,8 @@ use rustc_ast::tokenstream::{AttrTokenTree, DelimSpan, LazyAttrTokenStream, Spac
 use rustc_ast::{self as ast};
 use rustc_ast::{AttrVec, Attribute, HasAttrs, HasTokens};
 use rustc_errors::PResult;
-use rustc_span::{sym, Span};
+use rustc_session::parse::ParseSess;
+use rustc_span::{sym, Span, DUMMY_SP};
 
 use std::convert::TryInto;
 use std::ops::Range;
@@ -39,8 +40,13 @@ impl AttrWrapper {
     pub fn empty() -> AttrWrapper {
         AttrWrapper { attrs: AttrVec::new(), start_pos: usize::MAX }
     }
-    // FIXME: Delay span bug here?
-    pub(crate) fn take_for_recovery(self) -> AttrVec {
+
+    pub(crate) fn take_for_recovery(self, sess: &ParseSess) -> AttrVec {
+        sess.span_diagnostic.delay_span_bug(
+            self.attrs.get(0).map(|attr| attr.span).unwrap_or(DUMMY_SP),
+            "AttrVec is taken for recovery but no error is produced",
+        );
+
         self.attrs
     }
 
@@ -273,16 +279,23 @@ impl<'a> Parser<'a> {
         let cursor_snapshot_next_calls = cursor_snapshot.num_next_calls;
         let mut end_pos = self.token_cursor.num_next_calls;
 
+        let mut captured_trailing = false;
+
         // Capture a trailing token if requested by the callback 'f'
         match trailing {
             TrailingToken::None => {}
+            TrailingToken::Gt => {
+                assert_eq!(self.token.kind, token::Gt);
+            }
             TrailingToken::Semi => {
                 assert_eq!(self.token.kind, token::Semi);
                 end_pos += 1;
+                captured_trailing = true;
             }
             TrailingToken::MaybeComma => {
                 if self.token.kind == token::Comma {
                     end_pos += 1;
+                    captured_trailing = true;
                 }
             }
         }
@@ -292,11 +305,7 @@ impl<'a> Parser<'a> {
         // was not actually bumped past it. When the `LazyAttrTokenStream` gets converted
         // into an `AttrTokenStream`, we will create the proper token.
         if self.token_cursor.break_last_token {
-            assert_eq!(
-                trailing,
-                TrailingToken::None,
-                "Cannot set `break_last_token` and have trailing token"
-            );
+            assert!(!captured_trailing, "Cannot set break_last_token and have trailing token");
             end_pos += 1;
         }
 
diff --git a/compiler/rustc_parse/src/parser/diagnostics.rs b/compiler/rustc_parse/src/parser/diagnostics.rs
index 887a4a6de33b..0bbe073fe2af 100644
--- a/compiler/rustc_parse/src/parser/diagnostics.rs
+++ b/compiler/rustc_parse/src/parser/diagnostics.rs
@@ -769,6 +769,10 @@ impl<'a> Parser<'a> {
         segment: &PathSegment,
         end: &[&TokenKind],
     ) -> bool {
+        if !self.may_recover() {
+            return false;
+        }
+
         // This function is intended to be invoked after parsing a path segment where there are two
         // cases:
         //
@@ -863,6 +867,10 @@ impl<'a> Parser<'a> {
     /// Check if a method call with an intended turbofish has been written without surrounding
     /// angle brackets.
     pub(super) fn check_turbofish_missing_angle_brackets(&mut self, segment: &mut PathSegment) {
+        if !self.may_recover() {
+            return;
+        }
+
         if token::ModSep == self.token.kind && segment.args.is_none() {
             let snapshot = self.create_snapshot_for_diagnostic();
             self.bump();
@@ -1396,6 +1404,10 @@ impl<'a> Parser<'a> {
         &mut self,
         base: P<T>,
     ) -> PResult<'a, P<T>> {
+        if !self.may_recover() {
+            return Ok(base);
+        }
+
         // Do not add `::` to expected tokens.
         if self.token == token::ModSep {
             if let Some(ty) = base.to_ty() {
@@ -1641,15 +1653,29 @@ impl<'a> Parser<'a> {
             (token::CloseDelim(Delimiter::Parenthesis), Some(begin_par_sp)) => {
                 self.bump();
 
+                let sm = self.sess.source_map();
+                let left = begin_par_sp;
+                let right = self.prev_token.span;
+                let left_snippet = if let Ok(snip) = sm.span_to_prev_source(left) &&
+                        !snip.ends_with(" ") {
+                                " ".to_string()
+                            } else {
+                                "".to_string()
+                            };
+
+                let right_snippet = if let Ok(snip) = sm.span_to_next_source(right) &&
+                        !snip.starts_with(" ") {
+                                " ".to_string()
+                            } else {
+                                "".to_string()
+                        };
+
                 self.sess.emit_err(ParenthesesInForHead {
-                    span: vec![begin_par_sp, self.prev_token.span],
+                    span: vec![left, right],
                     // With e.g. `for (x) in y)` this would replace `(x) in y)`
                     // with `x) in y)` which is syntactically invalid.
                     // However, this is prevented before we get here.
-                    sugg: ParenthesesInForHeadSugg {
-                        left: begin_par_sp,
-                        right: self.prev_token.span,
-                    },
+                    sugg: ParenthesesInForHeadSugg { left, right, left_snippet, right_snippet },
                 });
 
                 // Unwrap `(pat)` into `pat` to avoid the `unused_parens` lint.
@@ -2456,11 +2482,15 @@ impl<'a> Parser<'a> {
     }
 
     pub(crate) fn maybe_recover_unexpected_block_label(&mut self) -> bool {
-        let Some(label) = self.eat_label().filter(|_| {
-            self.eat(&token::Colon) && self.token.kind == token::OpenDelim(Delimiter::Brace)
-        }) else {
+        // Check for `'a : {`
+        if !(self.check_lifetime()
+            && self.look_ahead(1, |tok| tok.kind == token::Colon)
+            && self.look_ahead(2, |tok| tok.kind == token::OpenDelim(Delimiter::Brace)))
+        {
             return false;
-        };
+        }
+        let label = self.eat_label().expect("just checked if a label exists");
+        self.bump(); // eat `:`
         let span = label.ident.span.to(self.prev_token.span);
         let mut err = self.struct_span_err(span, "block label not supported here");
         err.span_label(span, "not supported here");
diff --git a/compiler/rustc_parse/src/parser/expr.rs b/compiler/rustc_parse/src/parser/expr.rs
index 98520a446a62..b072573af23f 100644
--- a/compiler/rustc_parse/src/parser/expr.rs
+++ b/compiler/rustc_parse/src/parser/expr.rs
@@ -9,9 +9,9 @@ use crate::errors::{
     ArrayBracketsInsteadOfSpaces, ArrayBracketsInsteadOfSpacesSugg, AsyncMoveOrderIncorrect,
     BinaryFloatLiteralNotSupported, BracesForStructLiteral, CatchAfterTry, CommaAfterBaseStruct,
     ComparisonInterpretedAsGeneric, ComparisonOrShiftInterpretedAsGenericSugg,
-    DoCatchSyntaxRemoved, DotDotDot, EqFieldInit, ExpectedElseBlock, ExpectedExpressionFoundLet,
-    FieldExpressionWithGeneric, FloatLiteralRequiresIntegerPart, FoundExprWouldBeStmt,
-    HexadecimalFloatLiteralNotSupported, IfExpressionMissingCondition,
+    DoCatchSyntaxRemoved, DotDotDot, EqFieldInit, ExpectedElseBlock, ExpectedEqForLetExpr,
+    ExpectedExpressionFoundLet, FieldExpressionWithGeneric, FloatLiteralRequiresIntegerPart,
+    FoundExprWouldBeStmt, HexadecimalFloatLiteralNotSupported, IfExpressionMissingCondition,
     IfExpressionMissingThenBlock, IfExpressionMissingThenBlockSub, IntLiteralTooLarge,
     InvalidBlockMacroSegment, InvalidComparisonOperator, InvalidComparisonOperatorSub,
     InvalidFloatLiteralSuffix, InvalidFloatLiteralWidth, InvalidIntLiteralWidth,
@@ -20,9 +20,9 @@ use crate::errors::{
     InvalidNumLiteralSuffix, LabeledLoopInBreak, LeadingPlusNotSupported, LeftArrowOperator,
     LifetimeInBorrowExpression, MacroInvocationWithQualifiedPath, MalformedLoopLabel,
     MatchArmBodyWithoutBraces, MatchArmBodyWithoutBracesSugg, MissingCommaAfterMatchArm,
-    MissingInInForLoop, MissingInInForLoopSub, MissingSemicolonBeforeArray, NoFieldsForFnCall,
-    NotAsNegationOperator, NotAsNegationOperatorSub, OctalFloatLiteralNotSupported,
-    OuterAttributeNotAllowedOnIfElse, ParenthesesWithStructFields,
+    MissingDotDot, MissingInInForLoop, MissingInInForLoopSub, MissingSemicolonBeforeArray,
+    NoFieldsForFnCall, NotAsNegationOperator, NotAsNegationOperatorSub,
+    OctalFloatLiteralNotSupported, OuterAttributeNotAllowedOnIfElse, ParenthesesWithStructFields,
     RequireColonAfterLabeledExpression, ShiftInterpretedAsGeneric, StructLiteralNotAllowedHere,
     StructLiteralNotAllowedHereSugg, TildeAsUnaryOperator, UnexpectedTokenAfterLabel,
     UnexpectedTokenAfterLabelSugg, WrapExpressionInParentheses,
@@ -33,6 +33,7 @@ use core::mem;
 use rustc_ast::ptr::P;
 use rustc_ast::token::{self, Delimiter, Token, TokenKind};
 use rustc_ast::tokenstream::Spacing;
+use rustc_ast::util::case::Case;
 use rustc_ast::util::classify;
 use rustc_ast::util::literal::LitError;
 use rustc_ast::util::parser::{prec_let_scrutinee_needs_par, AssocOp, Fixity};
@@ -132,7 +133,7 @@ impl<'a> Parser<'a> {
             Ok(expr) => Ok(expr),
             Err(mut err) => match self.token.ident() {
                 Some((Ident { name: kw::Underscore, .. }, false))
-                    if self.look_ahead(1, |t| t == &token::Comma) =>
+                    if self.may_recover() && self.look_ahead(1, |t| t == &token::Comma) =>
                 {
                     // Special-case handling of `foo(_, _, _)`
                     err.emit();
@@ -456,7 +457,7 @@ impl<'a> Parser<'a> {
                 return None;
             }
             (Some(op), _) => (op, self.token.span),
-            (None, Some((Ident { name: sym::and, span }, false))) => {
+            (None, Some((Ident { name: sym::and, span }, false))) if self.may_recover() => {
                 self.sess.emit_err(InvalidLogicalOperator {
                     span: self.token.span,
                     incorrect: "and".into(),
@@ -464,7 +465,7 @@ impl<'a> Parser<'a> {
                 });
                 (AssocOp::LAnd, span)
             }
-            (None, Some((Ident { name: sym::or, span }, false))) => {
+            (None, Some((Ident { name: sym::or, span }, false))) if self.may_recover() => {
                 self.sess.emit_err(InvalidLogicalOperator {
                     span: self.token.span,
                     incorrect: "or".into(),
@@ -615,7 +616,7 @@ impl<'a> Parser<'a> {
             token::Ident(..) if this.token.is_keyword(kw::Box) => {
                 make_it!(this, attrs, |this, _| this.parse_box_expr(lo))
             }
-            token::Ident(..) if this.is_mistaken_not_ident_negation() => {
+            token::Ident(..) if this.may_recover() && this.is_mistaken_not_ident_negation() => {
                 make_it!(this, attrs, |this, _| this.recover_not_expr(lo))
             }
             _ => return this.parse_dot_or_call_expr(Some(attrs)),
@@ -718,6 +719,10 @@ impl<'a> Parser<'a> {
         let cast_expr = match self.parse_as_cast_ty() {
             Ok(rhs) => mk_expr(self, lhs, rhs),
             Err(type_err) => {
+                if !self.may_recover() {
+                    return Err(type_err);
+                }
+
                 // Rewind to before attempting to parse the type with generics, to recover
                 // from situations like `x as usize < y` in which we first tried to parse
                 // `usize < y` as a type with generic arguments.
@@ -829,16 +834,11 @@ impl<'a> Parser<'a> {
                 ("cast", None)
             };
 
-        // Save the memory location of expr before parsing any following postfix operators.
-        // This will be compared with the memory location of the output expression.
-        // If they different we can assume we parsed another expression because the existing expression is not reallocated.
-        let addr_before = &*cast_expr as *const _ as usize;
         let with_postfix = self.parse_dot_or_call_expr_with_(cast_expr, span)?;
-        let changed = addr_before != &*with_postfix as *const _ as usize;
 
         // Check if an illegal postfix operator has been added after the cast.
-        // If the resulting expression is not a cast, or has a different memory location, it is an illegal postfix operator.
-        if !matches!(with_postfix.kind, ExprKind::Cast(_, _) | ExprKind::Type(_, _)) || changed {
+        // If the resulting expression is not a cast, it is an illegal postfix operator.
+        if !matches!(with_postfix.kind, ExprKind::Cast(_, _) | ExprKind::Type(_, _)) {
             let msg = format!(
                 "{cast_kind} cannot be followed by {}",
                 match with_postfix.kind {
@@ -1197,6 +1197,10 @@ impl<'a> Parser<'a> {
         seq: &mut PResult<'a, P<Expr>>,
         snapshot: Option<(SnapshotParser<'a>, ExprKind)>,
     ) -> Option<P<Expr>> {
+        if !self.may_recover() {
+            return None;
+        }
+
         match (seq.as_mut(), snapshot) {
             (Err(err), Some((mut snapshot, ExprKind::Path(None, path)))) => {
                 snapshot.bump(); // `(`
@@ -1360,7 +1364,7 @@ impl<'a> Parser<'a> {
             )
         } else if self.check_inline_const(0) {
             self.parse_const_block(lo.to(self.token.span), false)
-        } else if self.is_do_catch_block() {
+        } else if self.may_recover() && self.is_do_catch_block() {
             self.recover_do_catch()
         } else if self.is_try_block() {
             self.expect_keyword(kw::Try)?;
@@ -1532,6 +1536,7 @@ impl<'a> Parser<'a> {
         {
             self.parse_block_expr(label, lo, BlockCheckMode::Default)
         } else if !ate_colon
+            && self.may_recover()
             && (matches!(self.token.kind, token::CloseDelim(_) | token::Comma)
                 || self.token.is_op())
         {
@@ -1999,6 +2004,10 @@ impl<'a> Parser<'a> {
         prev_span: Span,
         open_delim_span: Span,
     ) -> PResult<'a, ()> {
+        if !self.may_recover() {
+            return Ok(());
+        }
+
         if self.token.kind == token::Comma {
             if !self.sess.source_map().is_multiline(prev_span.until(self.token.span)) {
                 return Ok(());
@@ -2039,7 +2048,7 @@ impl<'a> Parser<'a> {
         lo: Span,
         blk_mode: BlockCheckMode,
     ) -> PResult<'a, P<Expr>> {
-        if self.is_array_like_block() {
+        if self.may_recover() && self.is_array_like_block() {
             if let Some(arr) = self.maybe_suggest_brackets_instead_of_braces(lo) {
                 return Ok(arr);
             }
@@ -2082,7 +2091,7 @@ impl<'a> Parser<'a> {
             if self.eat_keyword(kw::Static) { Movability::Static } else { Movability::Movable };
 
         let asyncness = if self.token.uninterpolated_span().rust_2018() {
-            self.parse_asyncness()
+            self.parse_asyncness(Case::Sensitive)
         } else {
             Async::No
         };
@@ -2112,6 +2121,8 @@ impl<'a> Parser<'a> {
             // HACK: This is needed so we can detect whether we're inside a macro,
             // where regular assumptions about what tokens can follow other tokens
             // don't necessarily apply.
+            && self.may_recover()
+            // FIXME(Nilstrieb): Remove this check once `may_recover` actually stops recovery
             && self.subparser_name.is_none()
         {
             // It is likely that the closure body is a block but where the
@@ -2261,7 +2272,7 @@ impl<'a> Parser<'a> {
                 self.mk_block_err(cond_span.shrink_to_hi())
             }
         } else {
-            let attrs = self.parse_outer_attributes()?.take_for_recovery(); // For recovery.
+            let attrs = self.parse_outer_attributes()?; // For recovery.
             let block = if self.check(&token::OpenDelim(Delimiter::Brace)) {
                 self.parse_block()?
             } else {
@@ -2278,7 +2289,7 @@ impl<'a> Parser<'a> {
                     })?
                 }
             };
-            self.error_on_if_block_attrs(lo, false, block.span, &attrs);
+            self.error_on_if_block_attrs(lo, false, block.span, attrs);
             block
         };
         let els = if self.eat_keyword(kw::Else) { Some(self.parse_else_expr()?) } else { None };
@@ -2319,7 +2330,15 @@ impl<'a> Parser<'a> {
             RecoverColon::Yes,
             CommaRecoveryMode::LikelyTuple,
         )?;
-        self.expect(&token::Eq)?;
+        if self.token == token::EqEq {
+            self.sess.emit_err(ExpectedEqForLetExpr {
+                span: self.token.span,
+                sugg_span: self.token.span,
+            });
+            self.bump();
+        } else {
+            self.expect(&token::Eq)?;
+        }
         let expr = self.with_res(self.restrictions | Restrictions::NO_STRUCT_LITERAL, |this| {
             this.parse_assoc_expr_with(1 + prec_let_scrutinee_needs_par(), None.into())
         })?;
@@ -2331,7 +2350,7 @@ impl<'a> Parser<'a> {
     /// Parses an `else { ... }` expression (`else` token already eaten).
     fn parse_else_expr(&mut self) -> PResult<'a, P<Expr>> {
         let else_span = self.prev_token.span; // `else`
-        let attrs = self.parse_outer_attributes()?.take_for_recovery(); // For recovery.
+        let attrs = self.parse_outer_attributes()?; // For recovery.
         let expr = if self.eat_keyword(kw::If) {
             self.parse_if_expr()?
         } else if self.check(&TokenKind::OpenDelim(Delimiter::Brace)) {
@@ -2366,7 +2385,7 @@ impl<'a> Parser<'a> {
                 },
             }
         };
-        self.error_on_if_block_attrs(else_span, true, expr.span, &attrs);
+        self.error_on_if_block_attrs(else_span, true, expr.span, attrs);
         Ok(expr)
     }
 
@@ -2375,8 +2394,13 @@ impl<'a> Parser<'a> {
         ctx_span: Span,
         is_ctx_else: bool,
         branch_span: Span,
-        attrs: &[ast::Attribute],
+        attrs: AttrWrapper,
     ) {
+        if attrs.is_empty() {
+            return;
+        }
+
+        let attrs: &[ast::Attribute] = &attrs.take_for_recovery(self.sess);
         let (attributes, last) = match attrs {
             [] => return,
             [x0 @ xn] | [x0, .., xn] => (x0.span.to(xn.span), xn.span),
@@ -2865,7 +2889,7 @@ impl<'a> Parser<'a> {
         };
 
         while self.token != token::CloseDelim(close_delim) {
-            if self.eat(&token::DotDot) {
+            if self.eat(&token::DotDot) || self.recover_struct_field_dots(close_delim) {
                 let exp_span = self.prev_token.span;
                 // We permit `.. }` on the left-hand side of a destructuring assignment.
                 if self.check(&token::CloseDelim(close_delim)) {
@@ -3012,6 +3036,18 @@ impl<'a> Parser<'a> {
         self.recover_stmt();
     }
 
+    fn recover_struct_field_dots(&mut self, close_delim: Delimiter) -> bool {
+        if !self.look_ahead(1, |t| *t == token::CloseDelim(close_delim))
+            && self.eat(&token::DotDotDot)
+        {
+            // recover from typo of `...`, suggest `..`
+            let span = self.prev_token.span;
+            self.sess.emit_err(MissingDotDot { token_span: span, sugg_span: span });
+            return true;
+        }
+        false
+    }
+
     /// Parses `ident (COLON expr)?`.
     fn parse_expr_field(&mut self) -> PResult<'a, ExprField> {
         let attrs = self.parse_outer_attributes()?;
@@ -3142,6 +3178,8 @@ impl<'a> Parser<'a> {
                 && this.token.kind == token::Semi
             {
                 TrailingToken::Semi
+            } else if this.token.kind == token::Gt {
+                TrailingToken::Gt
             } else {
                 // FIXME - pass this through from the place where we know
                 // we need a comma, rather than assuming that `#[attr] expr,`
diff --git a/compiler/rustc_parse/src/parser/item.rs b/compiler/rustc_parse/src/parser/item.rs
index bda301c52e96..494f0cf56a80 100644
--- a/compiler/rustc_parse/src/parser/item.rs
+++ b/compiler/rustc_parse/src/parser/item.rs
@@ -8,6 +8,7 @@ use rustc_ast::ast::*;
 use rustc_ast::ptr::P;
 use rustc_ast::token::{self, Delimiter, TokenKind};
 use rustc_ast::tokenstream::{DelimSpan, TokenStream, TokenTree};
+use rustc_ast::util::case::Case;
 use rustc_ast::{self as ast, AttrVec, Attribute, DUMMY_NODE_ID};
 use rustc_ast::{Async, Const, Defaultness, IsAuto, Mutability, Unsafe, UseTree, UseTreeKind};
 use rustc_ast::{BindingAnnotation, Block, FnDecl, FnSig, Param, SelfKind};
@@ -34,7 +35,7 @@ impl<'a> Parser<'a> {
 
     /// Parses a `mod <foo> { ... }` or `mod <foo>;` item.
     fn parse_item_mod(&mut self, attrs: &mut AttrVec) -> PResult<'a, ItemInfo> {
-        let unsafety = self.parse_unsafety();
+        let unsafety = self.parse_unsafety(Case::Sensitive);
         self.expect_keyword(kw::Mod)?;
         let id = self.parse_ident()?;
         let mod_kind = if self.eat(&token::Semi) {
@@ -143,8 +144,15 @@ impl<'a> Parser<'a> {
         let lo = self.token.span;
         let vis = self.parse_visibility(FollowedByType::No)?;
         let mut def = self.parse_defaultness();
-        let kind =
-            self.parse_item_kind(&mut attrs, mac_allowed, lo, &vis, &mut def, fn_parse_mode)?;
+        let kind = self.parse_item_kind(
+            &mut attrs,
+            mac_allowed,
+            lo,
+            &vis,
+            &mut def,
+            fn_parse_mode,
+            Case::Sensitive,
+        )?;
         if let Some((ident, kind)) = kind {
             self.error_on_unconsumed_default(def, &kind);
             let span = lo.to(self.prev_token.span);
@@ -205,16 +213,17 @@ impl<'a> Parser<'a> {
         vis: &Visibility,
         def: &mut Defaultness,
         fn_parse_mode: FnParseMode,
+        case: Case,
     ) -> PResult<'a, Option<ItemInfo>> {
         let def_final = def == &Defaultness::Final;
-        let mut def = || mem::replace(def, Defaultness::Final);
+        let mut def_ = || mem::replace(def, Defaultness::Final);
 
-        let info = if self.eat_keyword(kw::Use) {
+        let info = if self.eat_keyword_case(kw::Use, case) {
             self.parse_use_item()?
-        } else if self.check_fn_front_matter(def_final) {
+        } else if self.check_fn_front_matter(def_final, case) {
             // FUNCTION ITEM
             let (ident, sig, generics, body) = self.parse_fn(attrs, fn_parse_mode, lo, vis)?;
-            (ident, ItemKind::Fn(Box::new(Fn { defaultness: def(), sig, generics, body })))
+            (ident, ItemKind::Fn(Box::new(Fn { defaultness: def_(), sig, generics, body })))
         } else if self.eat_keyword(kw::Extern) {
             if self.eat_keyword(kw::Crate) {
                 // EXTERN CRATE
@@ -225,7 +234,7 @@ impl<'a> Parser<'a> {
             }
         } else if self.is_unsafe_foreign_mod() {
             // EXTERN BLOCK
-            let unsafety = self.parse_unsafety();
+            let unsafety = self.parse_unsafety(Case::Sensitive);
             self.expect_keyword(kw::Extern)?;
             self.parse_item_foreign_mod(attrs, unsafety)?
         } else if self.is_static_global() {
@@ -234,15 +243,15 @@ impl<'a> Parser<'a> {
             let m = self.parse_mutability();
             let (ident, ty, expr) = self.parse_item_global(Some(m))?;
             (ident, ItemKind::Static(ty, m, expr))
-        } else if let Const::Yes(const_span) = self.parse_constness() {
+        } else if let Const::Yes(const_span) = self.parse_constness(Case::Sensitive) {
             // CONST ITEM
             if self.token.is_keyword(kw::Impl) {
                 // recover from `const impl`, suggest `impl const`
-                self.recover_const_impl(const_span, attrs, def())?
+                self.recover_const_impl(const_span, attrs, def_())?
             } else {
                 self.recover_const_mut(const_span);
                 let (ident, ty, expr) = self.parse_item_global(None)?;
-                (ident, ItemKind::Const(def(), ty, expr))
+                (ident, ItemKind::Const(def_(), ty, expr))
             }
         } else if self.check_keyword(kw::Trait) || self.check_auto_or_unsafe_trait_item() {
             // TRAIT ITEM
@@ -251,7 +260,7 @@ impl<'a> Parser<'a> {
             || self.check_keyword(kw::Unsafe) && self.is_keyword_ahead(1, &[kw::Impl])
         {
             // IMPL ITEM
-            self.parse_item_impl(attrs, def())?
+            self.parse_item_impl(attrs, def_())?
         } else if self.check_keyword(kw::Mod)
             || self.check_keyword(kw::Unsafe) && self.is_keyword_ahead(1, &[kw::Mod])
         {
@@ -259,7 +268,7 @@ impl<'a> Parser<'a> {
             self.parse_item_mod(attrs)?
         } else if self.eat_keyword(kw::Type) {
             // TYPE ITEM
-            self.parse_type_alias(def())?
+            self.parse_type_alias(def_())?
         } else if self.eat_keyword(kw::Enum) {
             // ENUM ITEM
             self.parse_item_enum()?
@@ -286,6 +295,19 @@ impl<'a> Parser<'a> {
         } else if self.isnt_macro_invocation() && vis.kind.is_pub() {
             self.recover_missing_kw_before_item()?;
             return Ok(None);
+        } else if self.isnt_macro_invocation() && case == Case::Sensitive {
+            _ = def_;
+
+            // Recover wrong cased keywords
+            return self.parse_item_kind(
+                attrs,
+                macros_allowed,
+                lo,
+                vis,
+                def,
+                fn_parse_mode,
+                Case::Insensitive,
+            );
         } else if macros_allowed && self.check_path() {
             // MACRO INVOCATION ITEM
             (Ident::empty(), ItemKind::MacCall(P(self.parse_item_macro(vis)?)))
@@ -538,7 +560,7 @@ impl<'a> Parser<'a> {
         attrs: &mut AttrVec,
         defaultness: Defaultness,
     ) -> PResult<'a, ItemInfo> {
-        let unsafety = self.parse_unsafety();
+        let unsafety = self.parse_unsafety(Case::Sensitive);
         self.expect_keyword(kw::Impl)?;
 
         // First, parse generic parameters if necessary.
@@ -552,7 +574,7 @@ impl<'a> Parser<'a> {
             generics
         };
 
-        let constness = self.parse_constness();
+        let constness = self.parse_constness(Case::Sensitive);
         if let Const::Yes(span) = constness {
             self.sess.gated_spans.gate(sym::const_trait_impl, span);
         }
@@ -796,7 +818,7 @@ impl<'a> Parser<'a> {
 
     /// Parses `unsafe? auto? trait Foo { ... }` or `trait Foo = Bar;`.
     fn parse_item_trait(&mut self, attrs: &mut AttrVec, lo: Span) -> PResult<'a, ItemInfo> {
-        let unsafety = self.parse_unsafety();
+        let unsafety = self.parse_unsafety(Case::Sensitive);
         // Parse optional `auto` prefix.
         let is_auto = if self.eat_keyword(kw::Auto) { IsAuto::Yes } else { IsAuto::No };
 
@@ -971,6 +993,23 @@ impl<'a> Parser<'a> {
             if self.eat(&token::ModSep) {
                 self.parse_use_tree_glob_or_nested()?
             } else {
+                // Recover from using a colon as path separator.
+                while self.eat_noexpect(&token::Colon) {
+                    self.struct_span_err(self.prev_token.span, "expected `::`, found `:`")
+                        .span_suggestion_short(
+                            self.prev_token.span,
+                            "use double colon",
+                            "::",
+                            Applicability::MachineApplicable,
+                        )
+                        .note_once("import paths are delimited using `::`")
+                        .emit();
+
+                    // We parse the rest of the path and append it to the original prefix.
+                    self.parse_path_segments(&mut prefix.segments, PathStyle::Mod, None)?;
+                    prefix.span = lo.to(self.prev_token.span);
+                }
+
                 UseTreeKind::Simple(self.parse_rename()?, DUMMY_NODE_ID, DUMMY_NODE_ID)
             }
         };
@@ -1745,7 +1784,7 @@ impl<'a> Parser<'a> {
         let (ident, is_raw) = self.ident_or_err()?;
         if !is_raw && ident.is_reserved() {
             let snapshot = self.create_snapshot_for_diagnostic();
-            let err = if self.check_fn_front_matter(false) {
+            let err = if self.check_fn_front_matter(false, Case::Sensitive) {
                 let inherited_vis = Visibility {
                     span: rustc_span::DUMMY_SP,
                     kind: VisibilityKind::Inherited,
@@ -2155,7 +2194,7 @@ impl<'a> Parser<'a> {
     ///
     /// `check_pub` adds additional `pub` to the checks in case users place it
     /// wrongly, can be used to ensure `pub` never comes after `default`.
-    pub(super) fn check_fn_front_matter(&mut self, check_pub: bool) -> bool {
+    pub(super) fn check_fn_front_matter(&mut self, check_pub: bool, case: Case) -> bool {
         // We use an over-approximation here.
         // `const const`, `fn const` won't parse, but we're not stepping over other syntax either.
         // `pub` is added in case users got confused with the ordering like `async pub fn`,
@@ -2165,23 +2204,30 @@ impl<'a> Parser<'a> {
         } else {
             &[kw::Const, kw::Async, kw::Unsafe, kw::Extern]
         };
-        self.check_keyword(kw::Fn) // Definitely an `fn`.
+        self.check_keyword_case(kw::Fn, case) // Definitely an `fn`.
             // `$qual fn` or `$qual $qual`:
-            || quals.iter().any(|&kw| self.check_keyword(kw))
+            || quals.iter().any(|&kw| self.check_keyword_case(kw, case))
                 && self.look_ahead(1, |t| {
                     // `$qual fn`, e.g. `const fn` or `async fn`.
-                    t.is_keyword(kw::Fn)
+                    t.is_keyword_case(kw::Fn, case)
                     // Two qualifiers `$qual $qual` is enough, e.g. `async unsafe`.
-                    || t.is_non_raw_ident_where(|i| quals.contains(&i.name)
-                        // Rule out 2015 `const async: T = val`.
-                        && i.is_reserved()
+                    || (
+                        (
+                            t.is_non_raw_ident_where(|i|
+                                quals.contains(&i.name)
+                                    // Rule out 2015 `const async: T = val`.
+                                    && i.is_reserved()
+                            )
+                            || case == Case::Insensitive
+                                && t.is_non_raw_ident_where(|i| quals.iter().any(|qual| qual.as_str() == i.name.as_str().to_lowercase()))
+                        )
                         // Rule out unsafe extern block.
                         && !self.is_unsafe_foreign_mod())
                 })
             // `extern ABI fn`
-            || self.check_keyword(kw::Extern)
+            || self.check_keyword_case(kw::Extern, case)
                 && self.look_ahead(1, |t| t.can_begin_literal_maybe_minus())
-                && self.look_ahead(2, |t| t.is_keyword(kw::Fn))
+                && self.look_ahead(2, |t| t.is_keyword_case(kw::Fn, case))
     }
 
     /// Parses all the "front matter" (or "qualifiers") for a `fn` declaration,
@@ -2197,22 +2243,22 @@ impl<'a> Parser<'a> {
     /// `Visibility::Inherited` when no visibility is known.
     pub(super) fn parse_fn_front_matter(&mut self, orig_vis: &Visibility) -> PResult<'a, FnHeader> {
         let sp_start = self.token.span;
-        let constness = self.parse_constness();
+        let constness = self.parse_constness(Case::Insensitive);
 
         let async_start_sp = self.token.span;
-        let asyncness = self.parse_asyncness();
+        let asyncness = self.parse_asyncness(Case::Insensitive);
 
         let unsafe_start_sp = self.token.span;
-        let unsafety = self.parse_unsafety();
+        let unsafety = self.parse_unsafety(Case::Insensitive);
 
         let ext_start_sp = self.token.span;
-        let ext = self.parse_extern();
+        let ext = self.parse_extern(Case::Insensitive);
 
         if let Async::Yes { span, .. } = asyncness {
             self.ban_async_in_2015(span);
         }
 
-        if !self.eat_keyword(kw::Fn) {
+        if !self.eat_keyword_case(kw::Fn, Case::Insensitive) {
             // It is possible for `expect_one_of` to recover given the contents of
             // `self.expected_tokens`, therefore, do not use `self.unexpected()` which doesn't
             // account for this.
diff --git a/compiler/rustc_parse/src/parser/mod.rs b/compiler/rustc_parse/src/parser/mod.rs
index b934e087608a..14dc490fb023 100644
--- a/compiler/rustc_parse/src/parser/mod.rs
+++ b/compiler/rustc_parse/src/parser/mod.rs
@@ -22,6 +22,7 @@ use rustc_ast::token::{self, Delimiter, Nonterminal, Token, TokenKind};
 use rustc_ast::tokenstream::AttributesData;
 use rustc_ast::tokenstream::{self, DelimSpan, Spacing};
 use rustc_ast::tokenstream::{TokenStream, TokenTree};
+use rustc_ast::util::case::Case;
 use rustc_ast::AttrId;
 use rustc_ast::DUMMY_NODE_ID;
 use rustc_ast::{self as ast, AnonConst, AttrStyle, AttrVec, Const, Extern};
@@ -79,6 +80,7 @@ pub enum ForceCollect {
 pub enum TrailingToken {
     None,
     Semi,
+    Gt,
     /// If the trailing token is a comma, then capture it
     /// Otherwise, ignore the trailing token
     MaybeComma,
@@ -103,6 +105,7 @@ macro_rules! maybe_whole {
 macro_rules! maybe_recover_from_interpolated_ty_qpath {
     ($self: expr, $allow_qpath_recovery: expr) => {
         if $allow_qpath_recovery
+                    && $self.may_recover()
                     && $self.look_ahead(1, |t| t == &token::ModSep)
                     && let token::Interpolated(nt) = &$self.token.kind
                     && let token::NtTy(ty) = &**nt
@@ -114,6 +117,12 @@ macro_rules! maybe_recover_from_interpolated_ty_qpath {
     };
 }
 
+#[derive(Clone, Copy)]
+pub enum Recovery {
+    Allowed,
+    Forbidden,
+}
+
 #[derive(Clone)]
 pub struct Parser<'a> {
     pub sess: &'a ParseSess,
@@ -151,12 +160,15 @@ pub struct Parser<'a> {
     /// This allows us to recover when the user forget to add braces around
     /// multiple statements in the closure body.
     pub current_closure: Option<ClosureSpans>,
+    /// Whether the parser is allowed to do recovery.
+    /// This is disabled when parsing macro arguments, see #103534
+    pub recovery: Recovery,
 }
 
-// This type is used a lot, e.g. it's cloned when matching many declarative macro rules. Make sure
+// This type is used a lot, e.g. it's cloned when matching many declarative macro rules with nonterminals. Make sure
 // it doesn't unintentionally get bigger.
 #[cfg(all(target_arch = "x86_64", target_pointer_width = "64"))]
-rustc_data_structures::static_assert_size!(Parser<'_>, 328);
+rustc_data_structures::static_assert_size!(Parser<'_>, 336);
 
 /// Stores span information about a closure.
 #[derive(Clone)]
@@ -482,6 +494,7 @@ impl<'a> Parser<'a> {
                 inner_attr_ranges: Default::default(),
             },
             current_closure: None,
+            recovery: Recovery::Allowed,
         };
 
         // Make parser point to the first token.
@@ -490,6 +503,22 @@ impl<'a> Parser<'a> {
         parser
     }
 
+    pub fn forbid_recovery(mut self) -> Self {
+        self.recovery = Recovery::Forbidden;
+        self
+    }
+
+    /// Whether the parser is allowed to recover from broken code.
+    ///
+    /// If this returns false, recovering broken code into valid code (especially if this recovery does lookahead)
+    /// is not allowed. All recovery done by the parser must be gated behind this check.
+    ///
+    /// Technically, this only needs to restrict eager recovery by doing lookahead at more tokens.
+    /// But making the distinction is very subtle, and simply forbidding all recovery is a lot simpler to uphold.
+    fn may_recover(&self) -> bool {
+        matches!(self.recovery, Recovery::Allowed)
+    }
+
     pub fn unexpected<T>(&mut self) -> PResult<'a, T> {
         match self.expect_one_of(&[], &[]) {
             Err(e) => Err(e),
@@ -608,6 +637,20 @@ impl<'a> Parser<'a> {
         self.token.is_keyword(kw)
     }
 
+    fn check_keyword_case(&mut self, kw: Symbol, case: Case) -> bool {
+        if self.check_keyword(kw) {
+            return true;
+        }
+
+        if case == Case::Insensitive
+        && let Some((ident, /* is_raw */ false)) = self.token.ident()
+        && ident.as_str().to_lowercase() == kw.as_str().to_lowercase() {
+            true
+        } else {
+            false
+        }
+    }
+
     /// If the next token is the given keyword, eats it and returns `true`.
     /// Otherwise, returns `false`. An expectation is also added for diagnostics purposes.
     // Public for rustfmt usage.
@@ -620,6 +663,33 @@ impl<'a> Parser<'a> {
         }
     }
 
+    /// Eats a keyword, optionally ignoring the case.
+    /// If the case differs (and is ignored) an error is issued.
+    /// This is useful for recovery.
+    fn eat_keyword_case(&mut self, kw: Symbol, case: Case) -> bool {
+        if self.eat_keyword(kw) {
+            return true;
+        }
+
+        if case == Case::Insensitive
+        && let Some((ident, /* is_raw */ false)) = self.token.ident()
+        && ident.as_str().to_lowercase() == kw.as_str().to_lowercase() {
+            self
+                .struct_span_err(ident.span, format!("keyword `{kw}` is written in a wrong case"))
+                .span_suggestion(
+                    ident.span,
+                    "write it in the correct case",
+                    kw,
+                    Applicability::MachineApplicable
+                ).emit();
+
+            self.bump();
+            return true;
+        }
+
+        false
+    }
+
     fn eat_keyword_noexpect(&mut self, kw: Symbol) -> bool {
         if self.token.is_keyword(kw) {
             self.bump();
@@ -1099,8 +1169,8 @@ impl<'a> Parser<'a> {
     }
 
     /// Parses asyncness: `async` or nothing.
-    fn parse_asyncness(&mut self) -> Async {
-        if self.eat_keyword(kw::Async) {
+    fn parse_asyncness(&mut self, case: Case) -> Async {
+        if self.eat_keyword_case(kw::Async, case) {
             let span = self.prev_token.uninterpolated_span();
             Async::Yes { span, closure_id: DUMMY_NODE_ID, return_impl_trait_id: DUMMY_NODE_ID }
         } else {
@@ -1109,8 +1179,8 @@ impl<'a> Parser<'a> {
     }
 
     /// Parses unsafety: `unsafe` or nothing.
-    fn parse_unsafety(&mut self) -> Unsafe {
-        if self.eat_keyword(kw::Unsafe) {
+    fn parse_unsafety(&mut self, case: Case) -> Unsafe {
+        if self.eat_keyword_case(kw::Unsafe, case) {
             Unsafe::Yes(self.prev_token.uninterpolated_span())
         } else {
             Unsafe::No
@@ -1118,10 +1188,10 @@ impl<'a> Parser<'a> {
     }
 
     /// Parses constness: `const` or nothing.
-    fn parse_constness(&mut self) -> Const {
+    fn parse_constness(&mut self, case: Case) -> Const {
         // Avoid const blocks to be parsed as const items
         if self.look_ahead(1, |t| t != &token::OpenDelim(Delimiter::Brace))
-            && self.eat_keyword(kw::Const)
+            && self.eat_keyword_case(kw::Const, case)
         {
             Const::Yes(self.prev_token.uninterpolated_span())
         } else {
@@ -1376,8 +1446,8 @@ impl<'a> Parser<'a> {
     }
 
     /// Parses `extern string_literal?`.
-    fn parse_extern(&mut self) -> Extern {
-        if self.eat_keyword(kw::Extern) {
+    fn parse_extern(&mut self, case: Case) -> Extern {
+        if self.eat_keyword_case(kw::Extern, case) {
             let mut extern_span = self.prev_token.span;
             let abi = self.parse_abi();
             if let Some(abi) = abi {
diff --git a/compiler/rustc_parse/src/parser/path.rs b/compiler/rustc_parse/src/parser/path.rs
index fdc1af27f82e..d46565dea893 100644
--- a/compiler/rustc_parse/src/parser/path.rs
+++ b/compiler/rustc_parse/src/parser/path.rs
@@ -631,7 +631,9 @@ impl<'a> Parser<'a> {
     /// - A single-segment path.
     pub(super) fn expr_is_valid_const_arg(&self, expr: &P<rustc_ast::Expr>) -> bool {
         match &expr.kind {
-            ast::ExprKind::Block(_, _) | ast::ExprKind::Lit(_) => true,
+            ast::ExprKind::Block(_, _)
+            | ast::ExprKind::Lit(_)
+            | ast::ExprKind::IncludedBytes(..) => true,
             ast::ExprKind::Unary(ast::UnOp::Neg, expr) => {
                 matches!(expr.kind, ast::ExprKind::Lit(_))
             }
diff --git a/compiler/rustc_parse/src/parser/stmt.rs b/compiler/rustc_parse/src/parser/stmt.rs
index a61e77b7c3bf..18b661034e07 100644
--- a/compiler/rustc_parse/src/parser/stmt.rs
+++ b/compiler/rustc_parse/src/parser/stmt.rs
@@ -10,8 +10,8 @@ use super::{
 use crate::errors::{
     AssignmentElseNotAllowed, CompoundAssignmentExpressionInLet, ConstLetMutuallyExclusive,
     DocCommentDoesNotDocumentAnything, ExpectedStatementAfterOuterAttr, InvalidCurlyInLetElse,
-    InvalidExpressionInLetElse, InvalidVariableDeclaration, InvalidVariableDeclarationSub,
-    WrapExpressionInParentheses,
+    InvalidExpressionInLetElse, InvalidIdentiferStartsWithNumber, InvalidVariableDeclaration,
+    InvalidVariableDeclarationSub, WrapExpressionInParentheses,
 };
 use crate::maybe_whole;
 
@@ -19,7 +19,7 @@ use rustc_ast as ast;
 use rustc_ast::ptr::P;
 use rustc_ast::token::{self, Delimiter, TokenKind};
 use rustc_ast::util::classify;
-use rustc_ast::{AttrStyle, AttrVec, Attribute, LocalKind, MacCall, MacCallStmt, MacStmtStyle};
+use rustc_ast::{AttrStyle, AttrVec, LocalKind, MacCall, MacCallStmt, MacStmtStyle};
 use rustc_ast::{Block, BlockCheckMode, Expr, ExprKind, HasAttrs, Local, Stmt};
 use rustc_ast::{StmtKind, DUMMY_NODE_ID};
 use rustc_errors::{Applicability, DiagnosticBuilder, ErrorGuaranteed, PResult};
@@ -101,7 +101,7 @@ impl<'a> Parser<'a> {
             self.mk_stmt(lo.to(item.span), StmtKind::Item(P(item)))
         } else if self.eat(&token::Semi) {
             // Do not attempt to parse an expression if we're done here.
-            self.error_outer_attrs(&attrs.take_for_recovery());
+            self.error_outer_attrs(attrs);
             self.mk_stmt(lo, StmtKind::Empty)
         } else if self.token != token::CloseDelim(Delimiter::Brace) {
             // Remainder are line-expr stmts.
@@ -120,7 +120,7 @@ impl<'a> Parser<'a> {
             }
             self.mk_stmt(lo.to(e.span), StmtKind::Expr(e))
         } else {
-            self.error_outer_attrs(&attrs.take_for_recovery());
+            self.error_outer_attrs(attrs);
             return Ok(None);
         }))
     }
@@ -199,8 +199,10 @@ impl<'a> Parser<'a> {
 
     /// Error on outer attributes in this context.
     /// Also error if the previous token was a doc comment.
-    fn error_outer_attrs(&self, attrs: &[Attribute]) {
-        if let [.., last] = attrs {
+    fn error_outer_attrs(&self, attrs: AttrWrapper) {
+        if !attrs.is_empty()
+        && let attrs = attrs.take_for_recovery(self.sess)
+        && let attrs @ [.., last] = &*attrs {
             if last.is_doc_comment() {
                 self.sess.emit_err(DocCommentDoesNotDocumentAnything {
                     span: last.span,
@@ -262,6 +264,7 @@ impl<'a> Parser<'a> {
             self.bump();
         }
 
+        self.report_invalid_identifier_error()?;
         let (pat, colon) = self.parse_pat_before_ty(None, RecoverComma::Yes, "`let` bindings")?;
 
         let (err, ty) = if colon {
@@ -353,6 +356,17 @@ impl<'a> Parser<'a> {
         Ok(P(ast::Local { ty, pat, kind, id: DUMMY_NODE_ID, span: lo.to(hi), attrs, tokens: None }))
     }
 
+    /// report error for `let 1x = 123`
+    pub fn report_invalid_identifier_error(&mut self) -> PResult<'a, ()> {
+        if let token::Literal(lit) = self.token.uninterpolate().kind &&
+            let Err(_) = rustc_ast::Lit::from_token(&self.token) &&
+            (lit.kind == token::LitKind::Integer || lit.kind == token::LitKind::Float) &&
+            self.look_ahead(1, |t| matches!(t.kind, token::Eq) || matches!(t.kind, token::Colon ) ) {
+                return Err(self.sess.create_err(InvalidIdentiferStartsWithNumber { span: self.token.span }));
+        }
+        Ok(())
+    }
+
     fn check_let_else_init_bool_expr(&self, init: &ast::Expr) {
         if let ast::ExprKind::Binary(op, ..) = init.kind {
             if op.node.lazy() {
@@ -553,39 +567,46 @@ impl<'a> Parser<'a> {
         match stmt.kind {
             // Expression without semicolon.
             StmtKind::Expr(ref mut expr)
-                if self.token != token::Eof && classify::expr_requires_semi_to_be_stmt(expr) =>
-            {
+                if self.token != token::Eof && classify::expr_requires_semi_to_be_stmt(expr) => {
                 // Just check for errors and recover; do not eat semicolon yet.
-                if let Err(mut e) =
-                    self.expect_one_of(&[], &[token::Semi, token::CloseDelim(Delimiter::Brace)])
-                {
-                    if let TokenKind::DocComment(..) = self.token.kind {
-                        if let Ok(snippet) = self.span_to_snippet(self.token.span) {
-                            let sp = self.token.span;
-                            let marker = &snippet[..3];
-                            let (comment_marker, doc_comment_marker) = marker.split_at(2);
+                // `expect_one_of` returns PResult<'a, bool /* recovered */>
+                let replace_with_err =
+                    match self.expect_one_of(&[], &[token::Semi, token::CloseDelim(Delimiter::Brace)]) {
+                    // Recover from parser, skip type error to avoid extra errors.
+                    Ok(true) => true,
+                    Err(mut e) => {
+                        if let TokenKind::DocComment(..) = self.token.kind &&
+                            let Ok(snippet) = self.span_to_snippet(self.token.span) {
+                                let sp = self.token.span;
+                                let marker = &snippet[..3];
+                                let (comment_marker, doc_comment_marker) = marker.split_at(2);
 
-                            e.span_suggestion(
-                                sp.with_hi(sp.lo() + BytePos(marker.len() as u32)),
-                                &format!(
-                                    "add a space before `{}` to use a regular comment",
-                                    doc_comment_marker,
-                                ),
-                                format!("{} {}", comment_marker, doc_comment_marker),
-                                Applicability::MaybeIncorrect,
-                            );
+                                e.span_suggestion(
+                                    sp.with_hi(sp.lo() + BytePos(marker.len() as u32)),
+                                    &format!(
+                                        "add a space before `{}` to use a regular comment",
+                                        doc_comment_marker,
+                                    ),
+                                    format!("{} {}", comment_marker, doc_comment_marker),
+                                    Applicability::MaybeIncorrect,
+                                );
                         }
-                    }
-                    if let Err(mut e) =
-                        self.check_mistyped_turbofish_with_multiple_type_params(e, expr)
-                    {
-                        if recover.no() {
-                            return Err(e);
+
+                        if let Err(mut e) =
+                            self.check_mistyped_turbofish_with_multiple_type_params(e, expr)
+                        {
+                            if recover.no() {
+                                return Err(e);
+                            }
+                            e.emit();
+                            self.recover_stmt();
                         }
-                        e.emit();
-                        self.recover_stmt();
+                        true
                     }
-                    // Don't complain about type errors in body tail after parse error (#57383).
+                    _ => false
+                };
+                if replace_with_err {
+                    // We already emitted an error, so don't emit another type error
                     let sp = expr.span.to(self.prev_token.span);
                     *expr = self.mk_expr_err(sp);
                 }
diff --git a/compiler/rustc_parse/src/parser/ty.rs b/compiler/rustc_parse/src/parser/ty.rs
index 2a8512acf8cf..d6854f070251 100644
--- a/compiler/rustc_parse/src/parser/ty.rs
+++ b/compiler/rustc_parse/src/parser/ty.rs
@@ -1,9 +1,11 @@
 use super::{Parser, PathStyle, TokenType};
 
+use crate::errors::{FnPtrWithGenerics, FnPtrWithGenericsSugg};
 use crate::{maybe_recover_from_interpolated_ty_qpath, maybe_whole};
 
 use rustc_ast::ptr::P;
 use rustc_ast::token::{self, Delimiter, Token, TokenKind};
+use rustc_ast::util::case::Case;
 use rustc_ast::{
     self as ast, BareFnTy, FnRetTy, GenericBound, GenericBounds, GenericParam, Generics, Lifetime,
     MacCall, MutTy, Mutability, PolyTraitRef, TraitBoundModifier, TraitObjectSyntax, Ty, TyKind,
@@ -267,16 +269,21 @@ impl<'a> Parser<'a> {
         } else if self.eat_keyword(kw::Underscore) {
             // A type to be inferred `_`
             TyKind::Infer
-        } else if self.check_fn_front_matter(false) {
+        } else if self.check_fn_front_matter(false, Case::Sensitive) {
             // Function pointer type
-            self.parse_ty_bare_fn(lo, Vec::new(), recover_return_sign)?
+            self.parse_ty_bare_fn(lo, Vec::new(), None, recover_return_sign)?
         } else if self.check_keyword(kw::For) {
             // Function pointer type or bound list (trait object type) starting with a poly-trait.
             //   `for<'lt> [unsafe] [extern "ABI"] fn (&'lt S) -> T`
             //   `for<'lt> Trait1<'lt> + Trait2 + 'a`
             let lifetime_defs = self.parse_late_bound_lifetime_defs()?;
-            if self.check_fn_front_matter(false) {
-                self.parse_ty_bare_fn(lo, lifetime_defs, recover_return_sign)?
+            if self.check_fn_front_matter(false, Case::Sensitive) {
+                self.parse_ty_bare_fn(
+                    lo,
+                    lifetime_defs,
+                    Some(self.prev_token.span.shrink_to_lo()),
+                    recover_return_sign,
+                )?
             } else {
                 let path = self.parse_path(PathStyle::Type)?;
                 let parse_plus = allow_plus == AllowPlus::Yes && self.check_plus();
@@ -401,7 +408,7 @@ impl<'a> Parser<'a> {
                 .span_suggestions(
                     span.shrink_to_hi(),
                     "add `mut` or `const` here",
-                    ["mut ".to_string(), "const ".to_string()].into_iter(),
+                    ["mut ".to_string(), "const ".to_string()],
                     Applicability::HasPlaceholders,
                 )
                 .emit();
@@ -518,7 +525,8 @@ impl<'a> Parser<'a> {
     fn parse_ty_bare_fn(
         &mut self,
         lo: Span,
-        params: Vec<GenericParam>,
+        mut params: Vec<GenericParam>,
+        param_insertion_point: Option<Span>,
         recover_return_sign: RecoverReturnSign,
     ) -> PResult<'a, TyKind> {
         let inherited_vis = rustc_ast::Visibility {
@@ -529,6 +537,9 @@ impl<'a> Parser<'a> {
         let span_start = self.token.span;
         let ast::FnHeader { ext, unsafety, constness, asyncness } =
             self.parse_fn_front_matter(&inherited_vis)?;
+        if self.may_recover() && self.token.kind == TokenKind::Lt {
+            self.recover_fn_ptr_with_generics(lo, &mut params, param_insertion_point)?;
+        }
         let decl = self.parse_fn_decl(|_| false, AllowPlus::No, recover_return_sign)?;
         let whole_span = lo.to(self.prev_token.span);
         if let ast::Const::Yes(span) = constness {
@@ -544,6 +555,48 @@ impl<'a> Parser<'a> {
         Ok(TyKind::BareFn(P(BareFnTy { ext, unsafety, generic_params: params, decl, decl_span })))
     }
 
+    /// Recover from function pointer types with a generic parameter list (e.g. `fn<'a>(&'a str)`).
+    fn recover_fn_ptr_with_generics(
+        &mut self,
+        lo: Span,
+        params: &mut Vec<GenericParam>,
+        param_insertion_point: Option<Span>,
+    ) -> PResult<'a, ()> {
+        let generics = self.parse_generics()?;
+        let arity = generics.params.len();
+
+        let mut lifetimes: Vec<_> = generics
+            .params
+            .into_iter()
+            .filter(|param| matches!(param.kind, ast::GenericParamKind::Lifetime))
+            .collect();
+
+        let sugg = if !lifetimes.is_empty() {
+            let snippet =
+                lifetimes.iter().map(|param| param.ident.as_str()).intersperse(", ").collect();
+
+            let (left, snippet) = if let Some(span) = param_insertion_point {
+                (span, if params.is_empty() { snippet } else { format!(", {snippet}") })
+            } else {
+                (lo.shrink_to_lo(), format!("for<{snippet}> "))
+            };
+
+            Some(FnPtrWithGenericsSugg {
+                left,
+                snippet,
+                right: generics.span,
+                arity,
+                for_param_list_exists: param_insertion_point.is_some(),
+            })
+        } else {
+            None
+        };
+
+        self.sess.emit_err(FnPtrWithGenerics { span: generics.span, sugg });
+        params.append(&mut lifetimes);
+        Ok(())
+    }
+
     /// Emit an error for the given bad function pointer qualifier.
     fn error_fn_ptr_bad_qualifier(&self, span: Span, qual_span: Span, qual: &str) {
         self.struct_span_err(span, &format!("an `fn` pointer type cannot be `{}`", qual))
diff --git a/compiler/rustc_parse_format/src/lib.rs b/compiler/rustc_parse_format/src/lib.rs
index 1394993abade..54bf4d1d6b73 100644
--- a/compiler/rustc_parse_format/src/lib.rs
+++ b/compiler/rustc_parse_format/src/lib.rs
@@ -819,19 +819,19 @@ fn find_skips_from_snippet(
     };
 
     fn find_skips(snippet: &str, is_raw: bool) -> Vec<usize> {
-        let mut s = snippet.char_indices().peekable();
+        let mut s = snippet.char_indices();
         let mut skips = vec![];
         while let Some((pos, c)) = s.next() {
-            match (c, s.peek()) {
+            match (c, s.clone().next()) {
                 // skip whitespace and empty lines ending in '\\'
                 ('\\', Some((next_pos, '\n'))) if !is_raw => {
                     skips.push(pos);
-                    skips.push(*next_pos);
+                    skips.push(next_pos);
                     let _ = s.next();
 
-                    while let Some((pos, c)) = s.peek() {
+                    while let Some((pos, c)) = s.clone().next() {
                         if matches!(c, ' ' | '\n' | '\t') {
-                            skips.push(*pos);
+                            skips.push(pos);
                             let _ = s.next();
                         } else {
                             break;
@@ -839,7 +839,7 @@ fn find_skips_from_snippet(
                     }
                 }
                 ('\\', Some((next_pos, 'n' | 't' | 'r' | '0' | '\\' | '\'' | '\"'))) => {
-                    skips.push(*next_pos);
+                    skips.push(next_pos);
                     let _ = s.next();
                 }
                 ('\\', Some((_, 'x'))) if !is_raw => {
@@ -858,19 +858,30 @@ fn find_skips_from_snippet(
                     }
                     if let Some((next_pos, next_c)) = s.next() {
                         if next_c == '{' {
-                            skips.push(next_pos);
-                            let mut i = 0; // consume up to 6 hexanumeric chars + closing `}`
-                            while let (Some((next_pos, c)), true) = (s.next(), i < 7) {
-                                if c.is_digit(16) {
-                                    skips.push(next_pos);
-                                } else if c == '}' {
-                                    skips.push(next_pos);
-                                    break;
-                                } else {
-                                    break;
-                                }
-                                i += 1;
+                            // consume up to 6 hexanumeric chars
+                            let digits_len =
+                                s.clone().take(6).take_while(|(_, c)| c.is_digit(16)).count();
+
+                            let len_utf8 = s
+                                .as_str()
+                                .get(..digits_len)
+                                .and_then(|digits| u32::from_str_radix(digits, 16).ok())
+                                .and_then(char::from_u32)
+                                .map_or(1, char::len_utf8);
+
+                            // Skip the digits, for chars that encode to more than 1 utf-8 byte
+                            // exclude as many digits as it is greater than 1 byte
+                            //
+                            // So for a 3 byte character, exclude 2 digits
+                            let required_skips =
+                                digits_len.saturating_sub(len_utf8.saturating_sub(1));
+
+                            // skip '{' and '}' also
+                            for pos in (next_pos..).take(required_skips + 2) {
+                                skips.push(pos)
                             }
+
+                            s.nth(digits_len);
                         } else if next_c.is_digit(16) {
                             skips.push(next_pos);
                             // We suggest adding `{` and `}` when appropriate, accept it here as if
diff --git a/compiler/rustc_passes/src/check_attr.rs b/compiler/rustc_passes/src/check_attr.rs
index b19e85427e72..2b6ff0a5cb9d 100644
--- a/compiler/rustc_passes/src/check_attr.rs
+++ b/compiler/rustc_passes/src/check_attr.rs
@@ -119,13 +119,13 @@ impl CheckAttrVisitor<'_> {
                 }
                 sym::naked => self.check_naked(hir_id, attr, span, target),
                 sym::rustc_legacy_const_generics => {
-                    self.check_rustc_legacy_const_generics(&attr, span, target, item)
+                    self.check_rustc_legacy_const_generics(hir_id, &attr, span, target, item)
                 }
                 sym::rustc_lint_query_instability => {
-                    self.check_rustc_lint_query_instability(&attr, span, target)
+                    self.check_rustc_lint_query_instability(hir_id, &attr, span, target)
                 }
                 sym::rustc_lint_diagnostics => {
-                    self.check_rustc_lint_diagnostics(&attr, span, target)
+                    self.check_rustc_lint_diagnostics(hir_id, &attr, span, target)
                 }
                 sym::rustc_lint_opt_ty => self.check_rustc_lint_opt_ty(&attr, span, target),
                 sym::rustc_lint_opt_deny_field_access => {
@@ -135,11 +135,13 @@ impl CheckAttrVisitor<'_> {
                 | sym::rustc_dirty
                 | sym::rustc_if_this_changed
                 | sym::rustc_then_this_would_need => self.check_rustc_dirty_clean(&attr),
-                sym::cmse_nonsecure_entry => self.check_cmse_nonsecure_entry(attr, span, target),
+                sym::cmse_nonsecure_entry => {
+                    self.check_cmse_nonsecure_entry(hir_id, attr, span, target)
+                }
                 sym::collapse_debuginfo => self.check_collapse_debuginfo(attr, span, target),
                 sym::const_trait => self.check_const_trait(attr, span, target),
                 sym::must_not_suspend => self.check_must_not_suspend(&attr, span, target),
-                sym::must_use => self.check_must_use(hir_id, &attr, span, target),
+                sym::must_use => self.check_must_use(hir_id, &attr, target),
                 sym::rustc_pass_by_value => self.check_pass_by_value(&attr, span, target),
                 sym::rustc_allow_incoherent_impl => {
                     self.check_allow_incoherent_impl(&attr, span, target)
@@ -386,6 +388,7 @@ impl CheckAttrVisitor<'_> {
                 self.tcx.sess.emit_err(errors::AttrShouldBeAppliedToFn {
                     attr_span: attr.span,
                     defn_span: span,
+                    on_crate: hir_id == CRATE_HIR_ID,
                 });
                 false
             }
@@ -393,7 +396,13 @@ impl CheckAttrVisitor<'_> {
     }
 
     /// Checks if `#[cmse_nonsecure_entry]` is applied to a function definition.
-    fn check_cmse_nonsecure_entry(&self, attr: &Attribute, span: Span, target: Target) -> bool {
+    fn check_cmse_nonsecure_entry(
+        &self,
+        hir_id: HirId,
+        attr: &Attribute,
+        span: Span,
+        target: Target,
+    ) -> bool {
         match target {
             Target::Fn
             | Target::Method(MethodKind::Trait { body: true } | MethodKind::Inherent) => true,
@@ -401,6 +410,7 @@ impl CheckAttrVisitor<'_> {
                 self.tcx.sess.emit_err(errors::AttrShouldBeAppliedToFn {
                     attr_span: attr.span,
                     defn_span: span,
+                    on_crate: hir_id == CRATE_HIR_ID,
                 });
                 false
             }
@@ -465,9 +475,11 @@ impl CheckAttrVisitor<'_> {
                 true
             }
             _ => {
-                self.tcx
-                    .sess
-                    .emit_err(errors::TrackedCallerWrongLocation { attr_span, defn_span: span });
+                self.tcx.sess.emit_err(errors::TrackedCallerWrongLocation {
+                    attr_span,
+                    defn_span: span,
+                    on_crate: hir_id == CRATE_HIR_ID,
+                });
                 false
             }
         }
@@ -576,6 +588,7 @@ impl CheckAttrVisitor<'_> {
                 self.tcx.sess.emit_err(errors::AttrShouldBeAppliedToFn {
                     attr_span: attr.span,
                     defn_span: span,
+                    on_crate: hir_id == CRATE_HIR_ID,
                 });
                 false
             }
@@ -1163,17 +1176,7 @@ impl CheckAttrVisitor<'_> {
     }
 
     /// Warns against some misuses of `#[must_use]`
-    fn check_must_use(&self, hir_id: HirId, attr: &Attribute, span: Span, target: Target) -> bool {
-        let node = self.tcx.hir().get(hir_id);
-        if let Some(kind) = node.fn_kind() && let rustc_hir::IsAsync::Async = kind.asyncness() {
-            self.tcx.emit_spanned_lint(
-                UNUSED_ATTRIBUTES,
-                hir_id,
-                attr.span,
-                errors::MustUseAsync { span }
-            );
-        }
-
+    fn check_must_use(&self, hir_id: HirId, attr: &Attribute, target: Target) -> bool {
         if !matches!(
             target,
             Target::Fn
@@ -1240,7 +1243,7 @@ impl CheckAttrVisitor<'_> {
                     UNUSED_ATTRIBUTES,
                     hir_id,
                     attr.span,
-                    errors::Cold { span },
+                    errors::Cold { span, on_crate: hir_id == CRATE_HIR_ID },
                 );
             }
         }
@@ -1376,6 +1379,7 @@ impl CheckAttrVisitor<'_> {
     /// Checks if `#[rustc_legacy_const_generics]` is applied to a function and has a valid argument.
     fn check_rustc_legacy_const_generics(
         &self,
+        hir_id: HirId,
         attr: &Attribute,
         span: Span,
         target: Target,
@@ -1386,6 +1390,7 @@ impl CheckAttrVisitor<'_> {
             self.tcx.sess.emit_err(errors::AttrShouldBeAppliedToFn {
                 attr_span: attr.span,
                 defn_span: span,
+                on_crate: hir_id == CRATE_HIR_ID,
             });
             return false;
         }
@@ -1450,12 +1455,19 @@ impl CheckAttrVisitor<'_> {
 
     /// Helper function for checking that the provided attribute is only applied to a function or
     /// method.
-    fn check_applied_to_fn_or_method(&self, attr: &Attribute, span: Span, target: Target) -> bool {
+    fn check_applied_to_fn_or_method(
+        &self,
+        hir_id: HirId,
+        attr: &Attribute,
+        span: Span,
+        target: Target,
+    ) -> bool {
         let is_function = matches!(target, Target::Fn | Target::Method(..));
         if !is_function {
             self.tcx.sess.emit_err(errors::AttrShouldBeAppliedToFn {
                 attr_span: attr.span,
                 defn_span: span,
+                on_crate: hir_id == CRATE_HIR_ID,
             });
             false
         } else {
@@ -1467,17 +1479,24 @@ impl CheckAttrVisitor<'_> {
     /// or method.
     fn check_rustc_lint_query_instability(
         &self,
+        hir_id: HirId,
         attr: &Attribute,
         span: Span,
         target: Target,
     ) -> bool {
-        self.check_applied_to_fn_or_method(attr, span, target)
+        self.check_applied_to_fn_or_method(hir_id, attr, span, target)
     }
 
     /// Checks that the `#[rustc_lint_diagnostics]` attribute is only applied to a function or
     /// method.
-    fn check_rustc_lint_diagnostics(&self, attr: &Attribute, span: Span, target: Target) -> bool {
-        self.check_applied_to_fn_or_method(attr, span, target)
+    fn check_rustc_lint_diagnostics(
+        &self,
+        hir_id: HirId,
+        attr: &Attribute,
+        span: Span,
+        target: Target,
+    ) -> bool {
+        self.check_applied_to_fn_or_method(hir_id, attr, span, target)
     }
 
     /// Checks that the `#[rustc_lint_opt_ty]` attribute is only applied to a struct.
@@ -2062,7 +2081,7 @@ impl<'tcx> Visitor<'tcx> for CheckAttrVisitor<'tcx> {
         // so this lets us continue to run them while maintaining backwards compatibility.
         // In the long run, the checks should be harmonized.
         if let ItemKind::Macro(ref macro_def, _) = item.kind {
-            let def_id = item.def_id.to_def_id();
+            let def_id = item.owner_id.to_def_id();
             if macro_def.macro_rules && !self.tcx.has_attr(def_id, sym::macro_export) {
                 check_non_exported_macro_for_invalid_attrs(self.tcx, item);
             }
diff --git a/compiler/rustc_passes/src/dead.rs b/compiler/rustc_passes/src/dead.rs
index 6a97ad3fe86e..21b487d8ca1e 100644
--- a/compiler/rustc_passes/src/dead.rs
+++ b/compiler/rustc_passes/src/dead.rs
@@ -4,21 +4,24 @@
 
 use itertools::Itertools;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
-use rustc_errors::{pluralize, Applicability, MultiSpan};
+use rustc_errors::MultiSpan;
 use rustc_hir as hir;
 use rustc_hir::def::{CtorOf, DefKind, Res};
 use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_hir::intravisit::{self, Visitor};
 use rustc_hir::{Node, PatKind, TyKind};
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
-use rustc_middle::middle::privacy::AccessLevel;
+use rustc_middle::middle::privacy::Level;
 use rustc_middle::ty::query::Providers;
 use rustc_middle::ty::{self, DefIdTree, TyCtxt};
 use rustc_session::lint;
 use rustc_span::symbol::{sym, Symbol};
 use std::mem;
 
-use crate::errors::UselessAssignment;
+use crate::errors::{
+    ChangeFieldsToBeOfUnitType, IgnoredDerivedImpls, MultipleDeadCodes, ParentInfo,
+    UselessAssignment,
+};
 
 // Any local node that may call something in its body block should be
 // explored. For example, if it's a live Node::Item that is a
@@ -280,8 +283,8 @@ impl<'tcx> MarkSymbolVisitor<'tcx> {
     }
 
     fn visit_node(&mut self, node: Node<'tcx>) {
-        if let Node::ImplItem(hir::ImplItem { def_id, .. }) = node
-            && self.should_ignore_item(def_id.to_def_id())
+        if let Node::ImplItem(hir::ImplItem { owner_id, .. }) = node
+            && self.should_ignore_item(owner_id.to_def_id())
         {
             return;
         }
@@ -293,7 +296,7 @@ impl<'tcx> MarkSymbolVisitor<'tcx> {
         match node {
             Node::Item(item) => match item.kind {
                 hir::ItemKind::Struct(..) | hir::ItemKind::Union(..) => {
-                    let def = self.tcx.adt_def(item.def_id);
+                    let def = self.tcx.adt_def(item.owner_id);
                     self.repr_has_repr_c = def.repr().c();
                     self.repr_has_repr_simd = def.repr().simd();
 
@@ -306,7 +309,7 @@ impl<'tcx> MarkSymbolVisitor<'tcx> {
                 intravisit::walk_trait_item(self, trait_item);
             }
             Node::ImplItem(impl_item) => {
-                let item = self.tcx.local_parent(impl_item.def_id.def_id);
+                let item = self.tcx.local_parent(impl_item.owner_id.def_id);
                 if self.tcx.impl_trait_ref(item).is_none() {
                     //// If it's a type whose items are live, then it's live, too.
                     //// This is done to handle the case where, for example, the static
@@ -470,11 +473,6 @@ fn has_allow_dead_code_or_lang_attr_helper(
         return true;
     }
 
-    // (To be) stable attribute for #[lang = "oom"]
-    if tcx.sess.contains_name(attrs, sym::alloc_error_handler) {
-        return true;
-    }
-
     let def_id = tcx.hir().local_def_id(id);
     if tcx.def_kind(def_id).has_codegen_attrs() {
         let cg_attrs = tcx.codegen_fn_attrs(def_id);
@@ -517,10 +515,10 @@ fn check_item<'tcx>(
 ) {
     let allow_dead_code = has_allow_dead_code_or_lang_attr(tcx, id.hir_id());
     if allow_dead_code {
-        worklist.push(id.def_id.def_id);
+        worklist.push(id.owner_id.def_id);
     }
 
-    match tcx.def_kind(id.def_id) {
+    match tcx.def_kind(id.owner_id) {
         DefKind::Enum => {
             let item = tcx.hir().item(id);
             if let hir::ItemKind::Enum(ref enum_def, _) = item.kind {
@@ -540,15 +538,15 @@ fn check_item<'tcx>(
             }
         }
         DefKind::Impl => {
-            let of_trait = tcx.impl_trait_ref(id.def_id);
+            let of_trait = tcx.impl_trait_ref(id.owner_id);
 
             if of_trait.is_some() {
-                worklist.push(id.def_id.def_id);
+                worklist.push(id.owner_id.def_id);
             }
 
             // get DefIds from another query
             let local_def_ids = tcx
-                .associated_item_def_ids(id.def_id)
+                .associated_item_def_ids(id.owner_id)
                 .iter()
                 .filter_map(|def_id| def_id.as_local());
 
@@ -566,12 +564,12 @@ fn check_item<'tcx>(
             if let hir::ItemKind::Struct(ref variant_data, _) = item.kind
                 && let Some(ctor_hir_id) = variant_data.ctor_hir_id()
             {
-                struct_constructors.insert(tcx.hir().local_def_id(ctor_hir_id), item.def_id.def_id);
+                struct_constructors.insert(tcx.hir().local_def_id(ctor_hir_id), item.owner_id.def_id);
             }
         }
         DefKind::GlobalAsm => {
             // global_asm! is always live.
-            worklist.push(id.def_id.def_id);
+            worklist.push(id.owner_id.def_id);
         }
         _ => {}
     }
@@ -579,12 +577,12 @@ fn check_item<'tcx>(
 
 fn check_trait_item<'tcx>(tcx: TyCtxt<'tcx>, worklist: &mut Vec<LocalDefId>, id: hir::TraitItemId) {
     use hir::TraitItemKind::{Const, Fn};
-    if matches!(tcx.def_kind(id.def_id), DefKind::AssocConst | DefKind::AssocFn) {
+    if matches!(tcx.def_kind(id.owner_id), DefKind::AssocConst | DefKind::AssocFn) {
         let trait_item = tcx.hir().trait_item(id);
         if matches!(trait_item.kind, Const(_, Some(_)) | Fn(_, hir::TraitFn::Provided(_)))
             && has_allow_dead_code_or_lang_attr(tcx, trait_item.hir_id())
         {
-            worklist.push(trait_item.def_id.def_id);
+            worklist.push(trait_item.owner_id.def_id);
         }
     }
 }
@@ -594,23 +592,23 @@ fn check_foreign_item<'tcx>(
     worklist: &mut Vec<LocalDefId>,
     id: hir::ForeignItemId,
 ) {
-    if matches!(tcx.def_kind(id.def_id), DefKind::Static(_) | DefKind::Fn)
+    if matches!(tcx.def_kind(id.owner_id), DefKind::Static(_) | DefKind::Fn)
         && has_allow_dead_code_or_lang_attr(tcx, id.hir_id())
     {
-        worklist.push(id.def_id.def_id);
+        worklist.push(id.owner_id.def_id);
     }
 }
 
 fn create_and_seed_worklist<'tcx>(
     tcx: TyCtxt<'tcx>,
 ) -> (Vec<LocalDefId>, FxHashMap<LocalDefId, LocalDefId>) {
-    let access_levels = &tcx.privacy_access_levels(());
+    let effective_visibilities = &tcx.effective_visibilities(());
     // see `MarkSymbolVisitor::struct_constructors`
     let mut struct_constructors = Default::default();
-    let mut worklist = access_levels
+    let mut worklist = effective_visibilities
         .iter()
         .filter_map(|(&id, effective_vis)| {
-            effective_vis.is_public_at_level(AccessLevel::Reachable).then_some(id)
+            effective_vis.is_public_at_level(Level::Reachable).then_some(id)
         })
         // Seed entry point
         .chain(tcx.entry_fn(()).and_then(|(def_id, _)| def_id.as_local()))
@@ -698,99 +696,89 @@ impl<'tcx> DeadVisitor<'tcx> {
         parent_item: Option<LocalDefId>,
         is_positional: bool,
     ) {
-        if let Some(&first_id) = dead_codes.first() {
-            let tcx = self.tcx;
-            let names: Vec<_> = dead_codes
-                .iter()
-                .map(|&def_id| tcx.item_name(def_id.to_def_id()).to_string())
-                .collect();
-            let spans: Vec<_> = dead_codes
-                .iter()
-                .map(|&def_id| match tcx.def_ident_span(def_id) {
-                    Some(s) => s.with_ctxt(tcx.def_span(def_id).ctxt()),
-                    None => tcx.def_span(def_id),
+        let Some(&first_id) = dead_codes.first() else {
+            return;
+        };
+        let tcx = self.tcx;
+        let names: Vec<_> =
+            dead_codes.iter().map(|&def_id| tcx.item_name(def_id.to_def_id())).collect();
+        let spans: Vec<_> = dead_codes
+            .iter()
+            .map(|&def_id| match tcx.def_ident_span(def_id) {
+                Some(s) => s.with_ctxt(tcx.def_span(def_id).ctxt()),
+                None => tcx.def_span(def_id),
+            })
+            .collect();
+
+        let descr = tcx.def_kind(first_id).descr(first_id.to_def_id());
+        let num = dead_codes.len();
+        let multiple = num > 6;
+        let name_list = names.into();
+
+        let lint = if is_positional {
+            lint::builtin::UNUSED_TUPLE_STRUCT_FIELDS
+        } else {
+            lint::builtin::DEAD_CODE
+        };
+
+        let parent_info = if let Some(parent_item) = parent_item {
+            let parent_descr = tcx.def_kind(parent_item).descr(parent_item.to_def_id());
+            Some(ParentInfo {
+                num,
+                descr,
+                parent_descr,
+                span: tcx.def_ident_span(parent_item).unwrap(),
+            })
+        } else {
+            None
+        };
+
+        let encl_def_id = parent_item.unwrap_or(first_id);
+        let ignored_derived_impls =
+            if let Some(ign_traits) = self.ignored_derived_traits.get(&encl_def_id) {
+                let trait_list = ign_traits
+                    .iter()
+                    .map(|(trait_id, _)| self.tcx.item_name(*trait_id))
+                    .collect::<Vec<_>>();
+                let trait_list_len = trait_list.len();
+                Some(IgnoredDerivedImpls {
+                    name: self.tcx.item_name(encl_def_id.to_def_id()),
+                    trait_list: trait_list.into(),
+                    trait_list_len,
                 })
-                .collect();
-
-            let descr = tcx.def_kind(first_id).descr(first_id.to_def_id());
-            let span_len = dead_codes.len();
-            let names = match &names[..] {
-                _ if span_len > 6 => String::new(),
-                [name] => format!("`{name}` "),
-                [names @ .., last] => {
-                    format!(
-                        "{} and `{last}` ",
-                        names.iter().map(|name| format!("`{name}`")).join(", ")
-                    )
-                }
-                [] => unreachable!(),
+            } else {
+                None
             };
-            let msg = format!(
-                "{these}{descr}{s} {names}{are} never {participle}",
-                these = if span_len > 6 { "multiple " } else { "" },
-                s = pluralize!(span_len),
-                are = pluralize!("is", span_len),
-            );
 
-            tcx.struct_span_lint_hir(
-                if is_positional {
-                    lint::builtin::UNUSED_TUPLE_STRUCT_FIELDS
-                } else {
-                    lint::builtin::DEAD_CODE
-                },
-                tcx.hir().local_def_id_to_hir_id(first_id),
-                MultiSpan::from_spans(spans.clone()),
-                msg,
-                |err| {
-                    if is_positional {
-                        err.multipart_suggestion(
-                            &format!(
-                                "consider changing the field{s} to be of unit type to \
-                                      suppress this warning while preserving the field \
-                                      numbering, or remove the field{s}",
-                                s = pluralize!(span_len)
-                            ),
-                            spans.iter().map(|sp| (*sp, "()".to_string())).collect(),
-                            // "HasPlaceholders" because applying this fix by itself isn't
-                            // enough: All constructor calls have to be adjusted as well
-                            Applicability::HasPlaceholders,
-                        );
-                    }
+        let diag = if is_positional {
+            MultipleDeadCodes::UnusedTupleStructFields {
+                multiple,
+                num,
+                descr,
+                participle,
+                name_list,
+                change_fields_suggestion: ChangeFieldsToBeOfUnitType { num, spans: spans.clone() },
+                parent_info,
+                ignored_derived_impls,
+            }
+        } else {
+            MultipleDeadCodes::DeadCodes {
+                multiple,
+                num,
+                descr,
+                participle,
+                name_list,
+                parent_info,
+                ignored_derived_impls,
+            }
+        };
 
-                    if let Some(parent_item) = parent_item {
-                        let parent_descr = tcx.def_kind(parent_item).descr(parent_item.to_def_id());
-                        err.span_label(
-                            tcx.def_ident_span(parent_item).unwrap(),
-                            format!("{descr}{s} in this {parent_descr}", s = pluralize!(span_len)),
-                        );
-                    }
-
-                    let encl_def_id = parent_item.unwrap_or(first_id);
-                    if let Some(ign_traits) = self.ignored_derived_traits.get(&encl_def_id) {
-                        let traits_str = ign_traits
-                            .iter()
-                            .map(|(trait_id, _)| format!("`{}`", self.tcx.item_name(*trait_id)))
-                            .collect::<Vec<_>>()
-                            .join(" and ");
-                        let plural_s = pluralize!(ign_traits.len());
-                        let article = if ign_traits.len() > 1 { "" } else { "a " };
-                        let is_are = if ign_traits.len() > 1 { "these are" } else { "this is" };
-                        let msg = format!(
-                            "`{}` has {}derived impl{} for the trait{} {}, but {} \
-                            intentionally ignored during dead code analysis",
-                            self.tcx.item_name(encl_def_id.to_def_id()),
-                            article,
-                            plural_s,
-                            plural_s,
-                            traits_str,
-                            is_are
-                        );
-                        err.note(&msg);
-                    }
-                    err
-                },
-            );
-        }
+        self.tcx.emit_spanned_lint(
+            lint,
+            tcx.hir().local_def_id_to_hir_id(first_id),
+            MultiSpan::from_spans(spans.clone()),
+            diag,
+        );
     }
 
     fn warn_dead_fields_and_variants(
@@ -861,19 +849,19 @@ fn check_mod_deathness(tcx: TyCtxt<'_>, module: LocalDefId) {
     let module_items = tcx.hir_module_items(module);
 
     for item in module_items.items() {
-        if !live_symbols.contains(&item.def_id.def_id) {
-            let parent = tcx.local_parent(item.def_id.def_id);
+        if !live_symbols.contains(&item.owner_id.def_id) {
+            let parent = tcx.local_parent(item.owner_id.def_id);
             if parent != module && !live_symbols.contains(&parent) {
                 // We already have diagnosed something.
                 continue;
             }
-            visitor.check_definition(item.def_id.def_id);
+            visitor.check_definition(item.owner_id.def_id);
             continue;
         }
 
-        let def_kind = tcx.def_kind(item.def_id);
+        let def_kind = tcx.def_kind(item.owner_id);
         if let DefKind::Struct | DefKind::Union | DefKind::Enum = def_kind {
-            let adt = tcx.adt_def(item.def_id);
+            let adt = tcx.adt_def(item.owner_id);
             let mut dead_variants = Vec::new();
 
             for variant in adt.variants() {
@@ -917,7 +905,7 @@ fn check_mod_deathness(tcx: TyCtxt<'_>, module: LocalDefId) {
             }
 
             visitor.warn_dead_fields_and_variants(
-                item.def_id.def_id,
+                item.owner_id.def_id,
                 "constructed",
                 dead_variants,
                 false,
@@ -926,11 +914,11 @@ fn check_mod_deathness(tcx: TyCtxt<'_>, module: LocalDefId) {
     }
 
     for impl_item in module_items.impl_items() {
-        visitor.check_definition(impl_item.def_id.def_id);
+        visitor.check_definition(impl_item.owner_id.def_id);
     }
 
     for foreign_item in module_items.foreign_items() {
-        visitor.check_definition(foreign_item.def_id.def_id);
+        visitor.check_definition(foreign_item.owner_id.def_id);
     }
 
     // We do not warn trait items.
diff --git a/compiler/rustc_passes/src/diagnostic_items.rs b/compiler/rustc_passes/src/diagnostic_items.rs
index 3f991cf65724..a72056e00b1e 100644
--- a/compiler/rustc_passes/src/diagnostic_items.rs
+++ b/compiler/rustc_passes/src/diagnostic_items.rs
@@ -73,19 +73,19 @@ fn diagnostic_items<'tcx>(tcx: TyCtxt<'tcx>, cnum: CrateNum) -> DiagnosticItems
     let crate_items = tcx.hir_crate_items(());
 
     for id in crate_items.items() {
-        observe_item(tcx, &mut diagnostic_items, id.def_id.def_id);
+        observe_item(tcx, &mut diagnostic_items, id.owner_id.def_id);
     }
 
     for id in crate_items.trait_items() {
-        observe_item(tcx, &mut diagnostic_items, id.def_id.def_id);
+        observe_item(tcx, &mut diagnostic_items, id.owner_id.def_id);
     }
 
     for id in crate_items.impl_items() {
-        observe_item(tcx, &mut diagnostic_items, id.def_id.def_id);
+        observe_item(tcx, &mut diagnostic_items, id.owner_id.def_id);
     }
 
     for id in crate_items.foreign_items() {
-        observe_item(tcx, &mut diagnostic_items, id.def_id.def_id);
+        observe_item(tcx, &mut diagnostic_items, id.owner_id.def_id);
     }
 
     diagnostic_items
diff --git a/compiler/rustc_passes/src/entry.rs b/compiler/rustc_passes/src/entry.rs
index 38a259ca8846..5885f45ae45d 100644
--- a/compiler/rustc_passes/src/entry.rs
+++ b/compiler/rustc_passes/src/entry.rs
@@ -62,7 +62,7 @@ fn entry_point_type(ctxt: &EntryContext<'_>, id: ItemId, at_root: bool) -> Entry
     } else if ctxt.tcx.sess.contains_name(attrs, sym::rustc_main) {
         EntryPointType::RustcMainAttr
     } else {
-        if let Some(name) = ctxt.tcx.opt_item_name(id.def_id.to_def_id())
+        if let Some(name) = ctxt.tcx.opt_item_name(id.owner_id.to_def_id())
             && name == sym::main {
             if at_root {
                 // This is a top-level function so can be `main`.
@@ -82,7 +82,7 @@ fn attr_span_by_symbol(ctxt: &EntryContext<'_>, id: ItemId, sym: Symbol) -> Opti
 }
 
 fn find_item(id: ItemId, ctxt: &mut EntryContext<'_>) {
-    let at_root = ctxt.tcx.opt_local_parent(id.def_id.def_id) == Some(CRATE_DEF_ID);
+    let at_root = ctxt.tcx.opt_local_parent(id.owner_id.def_id) == Some(CRATE_DEF_ID);
 
     match entry_point_type(ctxt, id, at_root) {
         EntryPointType::None => {
@@ -90,7 +90,7 @@ fn find_item(id: ItemId, ctxt: &mut EntryContext<'_>) {
                 ctxt.tcx.sess.emit_err(AttrOnlyOnMain { span, attr: sym::unix_sigpipe });
             }
         }
-        _ if !matches!(ctxt.tcx.def_kind(id.def_id), DefKind::Fn) => {
+        _ if !matches!(ctxt.tcx.def_kind(id.owner_id), DefKind::Fn) => {
             for attr in [sym::start, sym::rustc_main] {
                 if let Some(span) = attr_span_by_symbol(ctxt, id, attr) {
                     ctxt.tcx.sess.emit_err(AttrOnlyInFunctions { span, attr });
@@ -102,16 +102,16 @@ fn find_item(id: ItemId, ctxt: &mut EntryContext<'_>) {
             if let Some(span) = attr_span_by_symbol(ctxt, id, sym::unix_sigpipe) {
                 ctxt.tcx.sess.emit_err(AttrOnlyOnRootMain { span, attr: sym::unix_sigpipe });
             }
-            ctxt.non_main_fns.push(ctxt.tcx.def_span(id.def_id));
+            ctxt.non_main_fns.push(ctxt.tcx.def_span(id.owner_id));
         }
         EntryPointType::RustcMainAttr => {
             if ctxt.attr_main_fn.is_none() {
-                ctxt.attr_main_fn = Some((id.def_id.def_id, ctxt.tcx.def_span(id.def_id)));
+                ctxt.attr_main_fn = Some((id.owner_id.def_id, ctxt.tcx.def_span(id.owner_id)));
             } else {
                 ctxt.tcx.sess.emit_err(MultipleRustcMain {
-                    span: ctxt.tcx.def_span(id.def_id.to_def_id()),
+                    span: ctxt.tcx.def_span(id.owner_id.to_def_id()),
                     first: ctxt.attr_main_fn.unwrap().1,
-                    additional: ctxt.tcx.def_span(id.def_id.to_def_id()),
+                    additional: ctxt.tcx.def_span(id.owner_id.to_def_id()),
                 });
             }
         }
@@ -120,11 +120,11 @@ fn find_item(id: ItemId, ctxt: &mut EntryContext<'_>) {
                 ctxt.tcx.sess.emit_err(AttrOnlyOnMain { span, attr: sym::unix_sigpipe });
             }
             if ctxt.start_fn.is_none() {
-                ctxt.start_fn = Some((id.def_id.def_id, ctxt.tcx.def_span(id.def_id)));
+                ctxt.start_fn = Some((id.owner_id.def_id, ctxt.tcx.def_span(id.owner_id)));
             } else {
                 ctxt.tcx.sess.emit_err(MultipleStartFunctions {
-                    span: ctxt.tcx.def_span(id.def_id),
-                    labeled: ctxt.tcx.def_span(id.def_id.to_def_id()),
+                    span: ctxt.tcx.def_span(id.owner_id),
+                    labeled: ctxt.tcx.def_span(id.owner_id.to_def_id()),
                     previous: ctxt.start_fn.unwrap().1,
                 });
             }
diff --git a/compiler/rustc_passes/src/errors.rs b/compiler/rustc_passes/src/errors.rs
index adaaf5392425..c6cd69add28a 100644
--- a/compiler/rustc_passes/src/errors.rs
+++ b/compiler/rustc_passes/src/errors.rs
@@ -4,7 +4,9 @@ use std::{
 };
 
 use rustc_ast::Label;
-use rustc_errors::{error_code, Applicability, ErrorGuaranteed, IntoDiagnostic, MultiSpan};
+use rustc_errors::{
+    error_code, Applicability, DiagnosticSymbolList, ErrorGuaranteed, IntoDiagnostic, MultiSpan,
+};
 use rustc_hir::{self as hir, ExprKind, Target};
 use rustc_macros::{Diagnostic, LintDiagnostic, Subdiagnostic};
 use rustc_middle::ty::{MainDefinition, Ty};
@@ -79,6 +81,7 @@ pub struct AttrShouldBeAppliedToFn {
     pub attr_span: Span,
     #[label]
     pub defn_span: Span,
+    pub on_crate: bool,
 }
 
 #[derive(Diagnostic)]
@@ -95,6 +98,7 @@ pub struct TrackedCallerWrongLocation {
     pub attr_span: Span,
     #[label]
     pub defn_span: Span,
+    pub on_crate: bool,
 }
 
 #[derive(Diagnostic)]
@@ -291,7 +295,7 @@ pub struct DocTestUnknownAny {
 #[note(no_op_note)]
 pub struct DocTestUnknownSpotlight {
     pub path: String,
-    #[suggestion_short(applicability = "machine-applicable", code = "notable_trait")]
+    #[suggestion(style = "short", applicability = "machine-applicable", code = "notable_trait")]
     pub span: Span,
 }
 
@@ -365,6 +369,7 @@ pub struct MustNotSuspend {
 pub struct Cold {
     #[label]
     pub span: Span,
+    pub on_crate: bool,
 }
 
 #[derive(LintDiagnostic)]
@@ -701,14 +706,6 @@ pub struct UnknownExternLangItem {
 #[diag(passes_missing_panic_handler)]
 pub struct MissingPanicHandler;
 
-#[derive(Diagnostic)]
-#[diag(passes_alloc_func_required)]
-pub struct AllocFuncRequired;
-
-#[derive(Diagnostic)]
-#[diag(passes_missing_alloc_error_handler)]
-pub struct MissingAllocErrorHandler;
-
 #[derive(Diagnostic)]
 #[diag(passes_missing_lang_item)]
 #[note]
@@ -744,6 +741,7 @@ pub struct InvalidAttrAtCrateLevel {
 }
 
 impl IntoDiagnostic<'_> for InvalidAttrAtCrateLevel {
+    #[track_caller]
     fn into_diagnostic(
         self,
         handler: &'_ rustc_errors::Handler,
@@ -876,6 +874,7 @@ pub struct BreakNonLoop<'a> {
 }
 
 impl<'a> IntoDiagnostic<'_> for BreakNonLoop<'a> {
+    #[track_caller]
     fn into_diagnostic(
         self,
         handler: &rustc_errors::Handler,
@@ -960,6 +959,7 @@ pub struct OutsideLoop<'a> {
     #[label]
     pub span: Span,
     pub name: &'a str,
+    pub is_break: bool,
 }
 
 #[derive(Diagnostic)]
@@ -1013,6 +1013,7 @@ pub struct NakedFunctionsAsmBlock {
 }
 
 impl IntoDiagnostic<'_> for NakedFunctionsAsmBlock {
+    #[track_caller]
     fn into_diagnostic(
         self,
         handler: &rustc_errors::Handler,
@@ -1136,6 +1137,7 @@ pub struct NoMainErr {
 }
 
 impl<'a> IntoDiagnostic<'a> for NoMainErr {
+    #[track_caller]
     fn into_diagnostic(
         self,
         handler: &'a rustc_errors::Handler,
@@ -1196,6 +1198,7 @@ pub struct DuplicateLangItem {
 }
 
 impl IntoDiagnostic<'_> for DuplicateLangItem {
+    #[track_caller]
     fn into_diagnostic(
         self,
         handler: &rustc_errors::Handler,
@@ -1449,3 +1452,59 @@ pub struct MissingConstErr {
     #[label]
     pub const_span: Span,
 }
+
+#[derive(LintDiagnostic)]
+pub enum MultipleDeadCodes<'tcx> {
+    #[diag(passes_dead_codes)]
+    DeadCodes {
+        multiple: bool,
+        num: usize,
+        descr: &'tcx str,
+        participle: &'tcx str,
+        name_list: DiagnosticSymbolList,
+        #[subdiagnostic]
+        parent_info: Option<ParentInfo<'tcx>>,
+        #[subdiagnostic]
+        ignored_derived_impls: Option<IgnoredDerivedImpls>,
+    },
+    #[diag(passes_dead_codes)]
+    UnusedTupleStructFields {
+        multiple: bool,
+        num: usize,
+        descr: &'tcx str,
+        participle: &'tcx str,
+        name_list: DiagnosticSymbolList,
+        #[subdiagnostic]
+        change_fields_suggestion: ChangeFieldsToBeOfUnitType,
+        #[subdiagnostic]
+        parent_info: Option<ParentInfo<'tcx>>,
+        #[subdiagnostic]
+        ignored_derived_impls: Option<IgnoredDerivedImpls>,
+    },
+}
+
+#[derive(Subdiagnostic)]
+#[label(passes_parent_info)]
+pub struct ParentInfo<'tcx> {
+    pub num: usize,
+    pub descr: &'tcx str,
+    pub parent_descr: &'tcx str,
+    #[primary_span]
+    pub span: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[note(passes_ignored_derived_impls)]
+pub struct IgnoredDerivedImpls {
+    pub name: Symbol,
+    pub trait_list: DiagnosticSymbolList,
+    pub trait_list_len: usize,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion(passes_change_fields_to_be_of_unit_type, applicability = "has-placeholders")]
+pub struct ChangeFieldsToBeOfUnitType {
+    pub num: usize,
+    #[suggestion_part(code = "()")]
+    pub spans: Vec<Span>,
+}
diff --git a/compiler/rustc_passes/src/hir_id_validator.rs b/compiler/rustc_passes/src/hir_id_validator.rs
index 3ee8c8bcb1de..88bb39debb11 100644
--- a/compiler/rustc_passes/src/hir_id_validator.rs
+++ b/compiler/rustc_passes/src/hir_id_validator.rs
@@ -126,7 +126,7 @@ impl<'a, 'hir> intravisit::Visitor<'hir> for HirIdValidator<'a, 'hir> {
 
     fn visit_item(&mut self, i: &'hir hir::Item<'hir>) {
         let mut inner_visitor = self.new_visitor(self.hir_map);
-        inner_visitor.check(i.def_id, |this| intravisit::walk_item(this, i));
+        inner_visitor.check(i.owner_id, |this| intravisit::walk_item(this, i));
     }
 
     fn visit_id(&mut self, hir_id: HirId) {
@@ -148,16 +148,16 @@ impl<'a, 'hir> intravisit::Visitor<'hir> for HirIdValidator<'a, 'hir> {
 
     fn visit_foreign_item(&mut self, i: &'hir hir::ForeignItem<'hir>) {
         let mut inner_visitor = self.new_visitor(self.hir_map);
-        inner_visitor.check(i.def_id, |this| intravisit::walk_foreign_item(this, i));
+        inner_visitor.check(i.owner_id, |this| intravisit::walk_foreign_item(this, i));
     }
 
     fn visit_trait_item(&mut self, i: &'hir hir::TraitItem<'hir>) {
         let mut inner_visitor = self.new_visitor(self.hir_map);
-        inner_visitor.check(i.def_id, |this| intravisit::walk_trait_item(this, i));
+        inner_visitor.check(i.owner_id, |this| intravisit::walk_trait_item(this, i));
     }
 
     fn visit_impl_item(&mut self, i: &'hir hir::ImplItem<'hir>) {
         let mut inner_visitor = self.new_visitor(self.hir_map);
-        inner_visitor.check(i.def_id, |this| intravisit::walk_impl_item(this, i));
+        inner_visitor.check(i.owner_id, |this| intravisit::walk_impl_item(this, i));
     }
 }
diff --git a/compiler/rustc_passes/src/hir_stats.rs b/compiler/rustc_passes/src/hir_stats.rs
index 33220fd2b395..140f02c046a6 100644
--- a/compiler/rustc_passes/src/hir_stats.rs
+++ b/compiler/rustc_passes/src/hir_stats.rs
@@ -560,13 +560,14 @@ impl<'v> ast_visit::Visitor<'v> for StatCollector<'v> {
     }
 
     fn visit_expr(&mut self, e: &'v ast::Expr) {
+        #[rustfmt::skip]
         record_variants!(
             (self, e, e.kind, Id::None, ast, Expr, ExprKind),
             [
                 Box, Array, ConstBlock, Call, MethodCall, Tup, Binary, Unary, Lit, Cast, Type, Let,
                 If, While, ForLoop, Loop, Match, Closure, Block, Async, Await, TryBlock, Assign,
                 AssignOp, Field, Index, Range, Underscore, Path, AddrOf, Break, Continue, Ret,
-                InlineAsm, MacCall, Struct, Repeat, Paren, Try, Yield, Yeet, Err
+                InlineAsm, MacCall, Struct, Repeat, Paren, Try, Yield, Yeet, IncludedBytes, Err
             ]
         );
         ast_visit::walk_expr(self, e)
diff --git a/compiler/rustc_passes/src/lang_items.rs b/compiler/rustc_passes/src/lang_items.rs
index 71b0735192ac..188efc528ef8 100644
--- a/compiler/rustc_passes/src/lang_items.rs
+++ b/compiler/rustc_passes/src/lang_items.rs
@@ -16,7 +16,7 @@ use crate::weak_lang_items;
 use rustc_hir as hir;
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::DefId;
-use rustc_hir::lang_items::{extract, GenericRequirement, ITEM_REFS};
+use rustc_hir::lang_items::{extract, GenericRequirement};
 use rustc_hir::{HirId, LangItem, LanguageItems, Target};
 use rustc_middle::ty::TyCtxt;
 use rustc_session::cstore::ExternCrate;
@@ -43,17 +43,17 @@ impl<'tcx> LanguageItemCollector<'tcx> {
     fn check_for_lang(&mut self, actual_target: Target, hir_id: HirId) {
         let attrs = self.tcx.hir().attrs(hir_id);
         if let Some((name, span)) = extract(&attrs) {
-            match ITEM_REFS.get(&name).cloned() {
+            match LangItem::from_name(name) {
                 // Known lang item with attribute on correct target.
-                Some((item_index, expected_target)) if actual_target == expected_target => {
-                    self.collect_item_extended(item_index, hir_id, span);
+                Some(lang_item) if actual_target == lang_item.target() => {
+                    self.collect_item_extended(lang_item, hir_id, span);
                 }
                 // Known lang item with attribute on incorrect target.
-                Some((_, expected_target)) => {
+                Some(lang_item) => {
                     self.tcx.sess.emit_err(LangItemOnIncorrectTarget {
                         span,
                         name,
-                        expected_target,
+                        expected_target: lang_item.target(),
                         actual_target,
                     });
                 }
@@ -65,12 +65,12 @@ impl<'tcx> LanguageItemCollector<'tcx> {
         }
     }
 
-    fn collect_item(&mut self, item_index: usize, item_def_id: DefId) {
+    fn collect_item(&mut self, lang_item: LangItem, item_def_id: DefId) {
         // Check for duplicates.
-        if let Some(original_def_id) = self.items.items[item_index] {
+        if let Some(original_def_id) = self.items.get(lang_item) {
             if original_def_id != item_def_id {
                 let local_span = self.tcx.hir().span_if_local(item_def_id);
-                let lang_item_name = LangItem::from_u32(item_index as u32).unwrap().name();
+                let lang_item_name = lang_item.name();
                 let crate_name = self.tcx.crate_name(item_def_id.krate);
                 let mut dependency_of = Empty;
                 let is_local = item_def_id.is_local();
@@ -139,17 +139,13 @@ impl<'tcx> LanguageItemCollector<'tcx> {
         }
 
         // Matched.
-        self.items.items[item_index] = Some(item_def_id);
-        if let Some(group) = LangItem::from_u32(item_index as u32).unwrap().group() {
-            self.items.groups[group as usize].push(item_def_id);
-        }
+        self.items.set(lang_item, item_def_id);
     }
 
     // Like collect_item() above, but also checks whether the lang item is declared
     // with the right number of generic arguments.
-    fn collect_item_extended(&mut self, item_index: usize, hir_id: HirId, span: Span) {
+    fn collect_item_extended(&mut self, lang_item: LangItem, hir_id: HirId, span: Span) {
         let item_def_id = self.tcx.hir().local_def_id(hir_id).to_def_id();
-        let lang_item = LangItem::from_u32(item_index as u32).unwrap();
         let name = lang_item.name();
 
         // Now check whether the lang_item has the expected number of generic
@@ -197,7 +193,7 @@ impl<'tcx> LanguageItemCollector<'tcx> {
             }
         }
 
-        self.collect_item(item_index, item_def_id);
+        self.collect_item(lang_item, item_def_id);
     }
 }
 
@@ -208,8 +204,8 @@ fn get_lang_items(tcx: TyCtxt<'_>, (): ()) -> LanguageItems {
 
     // Collect lang items in other crates.
     for &cnum in tcx.crates(()).iter() {
-        for &(def_id, item_index) in tcx.defined_lang_items(cnum).iter() {
-            collector.collect_item(item_index, def_id);
+        for &(def_id, lang_item) in tcx.defined_lang_items(cnum).iter() {
+            collector.collect_item(lang_item, def_id);
         }
     }
 
@@ -217,9 +213,9 @@ fn get_lang_items(tcx: TyCtxt<'_>, (): ()) -> LanguageItems {
     let crate_items = tcx.hir_crate_items(());
 
     for id in crate_items.items() {
-        collector.check_for_lang(Target::from_def_kind(tcx.def_kind(id.def_id)), id.hir_id());
+        collector.check_for_lang(Target::from_def_kind(tcx.def_kind(id.owner_id)), id.hir_id());
 
-        if matches!(tcx.def_kind(id.def_id), DefKind::Enum) {
+        if matches!(tcx.def_kind(id.owner_id), DefKind::Enum) {
             let item = tcx.hir().item(id);
             if let hir::ItemKind::Enum(def, ..) = &item.kind {
                 for variant in def.variants {
diff --git a/compiler/rustc_passes/src/layout_test.rs b/compiler/rustc_passes/src/layout_test.rs
index c1085094962a..5322baee7473 100644
--- a/compiler/rustc_passes/src/layout_test.rs
+++ b/compiler/rustc_passes/src/layout_test.rs
@@ -15,11 +15,11 @@ pub fn test_layout(tcx: TyCtxt<'_>) {
         // if the `rustc_attrs` feature is not enabled, don't bother testing layout
         for id in tcx.hir().items() {
             if matches!(
-                tcx.def_kind(id.def_id),
+                tcx.def_kind(id.owner_id),
                 DefKind::TyAlias | DefKind::Enum | DefKind::Struct | DefKind::Union
             ) {
-                for attr in tcx.get_attrs(id.def_id.to_def_id(), sym::rustc_layout) {
-                    dump_layout_of(tcx, id.def_id.def_id, attr);
+                for attr in tcx.get_attrs(id.owner_id.to_def_id(), sym::rustc_layout) {
+                    dump_layout_of(tcx, id.owner_id.def_id, attr);
                 }
             }
         }
diff --git a/compiler/rustc_passes/src/lib.rs b/compiler/rustc_passes/src/lib.rs
index 15f60f626c89..6e621b7eb5eb 100644
--- a/compiler/rustc_passes/src/lib.rs
+++ b/compiler/rustc_passes/src/lib.rs
@@ -5,8 +5,6 @@
 //! This API is completely unstable and subject to change.
 
 #![allow(rustc::potential_query_instability)]
-#![deny(rustc::untranslatable_diagnostic)]
-#![deny(rustc::diagnostic_outside_of_impl)]
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
 #![feature(iter_intersperse)]
 #![feature(let_chains)]
diff --git a/compiler/rustc_passes/src/liveness.rs b/compiler/rustc_passes/src/liveness.rs
index c6fe40f72fc6..c181de48a9ad 100644
--- a/compiler/rustc_passes/src/liveness.rs
+++ b/compiler/rustc_passes/src/liveness.rs
@@ -87,6 +87,7 @@ use self::VarKind::*;
 use rustc_ast::InlineAsmOptions;
 use rustc_data_structures::fx::FxIndexMap;
 use rustc_errors::Applicability;
+use rustc_errors::Diagnostic;
 use rustc_hir as hir;
 use rustc_hir::def::*;
 use rustc_hir::def_id::{DefId, LocalDefId};
@@ -1690,7 +1691,7 @@ impl<'tcx> Liveness<'_, 'tcx> {
         &self,
         name: &str,
         opt_body: Option<&hir::Body<'_>>,
-        err: &mut rustc_errors::DiagnosticBuilder<'_, ()>,
+        err: &mut Diagnostic,
     ) -> bool {
         let mut has_litstring = false;
         let Some(opt_body) = opt_body else {return false;};
diff --git a/compiler/rustc_passes/src/loops.rs b/compiler/rustc_passes/src/loops.rs
index 077194ec687b..b4cf19e4a34f 100644
--- a/compiler/rustc_passes/src/loops.rs
+++ b/compiler/rustc_passes/src/loops.rs
@@ -193,7 +193,7 @@ impl<'a, 'hir> CheckLoopVisitor<'a, 'hir> {
                 self.sess.emit_err(BreakInsideAsyncBlock { span, closure_span, name });
             }
             Normal | AnonConst => {
-                self.sess.emit_err(OutsideLoop { span, name });
+                self.sess.emit_err(OutsideLoop { span, name, is_break: name == "break" });
             }
         }
     }
diff --git a/compiler/rustc_passes/src/reachable.rs b/compiler/rustc_passes/src/reachable.rs
index 0f2879c1eff2..73ea06a6370d 100644
--- a/compiler/rustc_passes/src/reachable.rs
+++ b/compiler/rustc_passes/src/reachable.rs
@@ -12,7 +12,7 @@ use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_hir::intravisit::{self, Visitor};
 use rustc_hir::Node;
 use rustc_middle::middle::codegen_fn_attrs::{CodegenFnAttrFlags, CodegenFnAttrs};
-use rustc_middle::middle::privacy::{self, AccessLevel};
+use rustc_middle::middle::privacy::{self, Level};
 use rustc_middle::ty::query::Providers;
 use rustc_middle::ty::{self, DefIdTree, TyCtxt};
 use rustc_session::config::CrateType;
@@ -29,7 +29,7 @@ fn item_might_be_inlined(tcx: TyCtxt<'_>, item: &hir::Item<'_>, attrs: &CodegenF
     match item.kind {
         hir::ItemKind::Fn(ref sig, ..) if sig.header.is_const() => true,
         hir::ItemKind::Impl { .. } | hir::ItemKind::Fn(..) => {
-            let generics = tcx.generics_of(item.def_id);
+            let generics = tcx.generics_of(item.owner_id);
             generics.requires_monomorphization(tcx)
         }
         _ => false,
@@ -42,7 +42,7 @@ fn method_might_be_inlined(
     impl_src: LocalDefId,
 ) -> bool {
     let codegen_fn_attrs = tcx.codegen_fn_attrs(impl_item.hir_id().owner.to_def_id());
-    let generics = tcx.generics_of(impl_item.def_id);
+    let generics = tcx.generics_of(impl_item.owner_id);
     if codegen_fn_attrs.requests_inline() || generics.requires_monomorphization(tcx) {
         return true;
     }
@@ -216,7 +216,7 @@ impl<'tcx> ReachableContext<'tcx> {
                         if item_might_be_inlined(
                             self.tcx,
                             &item,
-                            self.tcx.codegen_fn_attrs(item.def_id),
+                            self.tcx.codegen_fn_attrs(item.owner_id),
                         ) {
                             self.visit_nested_body(body);
                         }
@@ -303,13 +303,13 @@ fn check_item<'tcx>(
     tcx: TyCtxt<'tcx>,
     id: hir::ItemId,
     worklist: &mut Vec<LocalDefId>,
-    access_levels: &privacy::AccessLevels,
+    effective_visibilities: &privacy::EffectiveVisibilities,
 ) {
-    if has_custom_linkage(tcx, id.def_id.def_id) {
-        worklist.push(id.def_id.def_id);
+    if has_custom_linkage(tcx, id.owner_id.def_id) {
+        worklist.push(id.owner_id.def_id);
     }
 
-    if !matches!(tcx.def_kind(id.def_id), DefKind::Impl) {
+    if !matches!(tcx.def_kind(id.owner_id), DefKind::Impl) {
         return;
     }
 
@@ -318,8 +318,8 @@ fn check_item<'tcx>(
     if let hir::ItemKind::Impl(hir::Impl { of_trait: Some(ref trait_ref), ref items, .. }) =
         item.kind
     {
-        if !access_levels.is_reachable(item.def_id.def_id) {
-            worklist.extend(items.iter().map(|ii_ref| ii_ref.id.def_id.def_id));
+        if !effective_visibilities.is_reachable(item.owner_id.def_id) {
+            worklist.extend(items.iter().map(|ii_ref| ii_ref.id.owner_id.def_id));
 
             let Res::Def(DefKind::Trait, trait_def_id) = trait_ref.path.res else {
                 unreachable!();
@@ -354,7 +354,7 @@ fn has_custom_linkage<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) -> bool {
 }
 
 fn reachable_set<'tcx>(tcx: TyCtxt<'tcx>, (): ()) -> FxHashSet<LocalDefId> {
-    let access_levels = &tcx.privacy_access_levels(());
+    let effective_visibilities = &tcx.effective_visibilities(());
 
     let any_library =
         tcx.sess.crate_types().iter().any(|ty| {
@@ -373,18 +373,16 @@ fn reachable_set<'tcx>(tcx: TyCtxt<'tcx>, (): ()) -> FxHashSet<LocalDefId> {
     //         If other crates link to us, they're going to expect to be able to
     //         use the lang items, so we need to be sure to mark them as
     //         exported.
-    reachable_context.worklist = access_levels
+    reachable_context.worklist = effective_visibilities
         .iter()
         .filter_map(|(&id, effective_vis)| {
-            effective_vis.is_public_at_level(AccessLevel::ReachableFromImplTrait).then_some(id)
+            effective_vis.is_public_at_level(Level::ReachableThroughImplTrait).then_some(id)
         })
         .collect::<Vec<_>>();
 
-    for item in tcx.lang_items().items().iter() {
-        if let Some(def_id) = *item {
-            if let Some(def_id) = def_id.as_local() {
-                reachable_context.worklist.push(def_id);
-            }
+    for (_, def_id) in tcx.lang_items().iter() {
+        if let Some(def_id) = def_id.as_local() {
+            reachable_context.worklist.push(def_id);
         }
     }
     {
@@ -399,12 +397,12 @@ fn reachable_set<'tcx>(tcx: TyCtxt<'tcx>, (): ()) -> FxHashSet<LocalDefId> {
         let crate_items = tcx.hir_crate_items(());
 
         for id in crate_items.items() {
-            check_item(tcx, id, &mut reachable_context.worklist, access_levels);
+            check_item(tcx, id, &mut reachable_context.worklist, effective_visibilities);
         }
 
         for id in crate_items.impl_items() {
-            if has_custom_linkage(tcx, id.def_id.def_id) {
-                reachable_context.worklist.push(id.def_id.def_id);
+            if has_custom_linkage(tcx, id.owner_id.def_id) {
+                reachable_context.worklist.push(id.owner_id.def_id);
             }
         }
     }
diff --git a/compiler/rustc_passes/src/stability.rs b/compiler/rustc_passes/src/stability.rs
index 9591aeb881f3..af49d438a22c 100644
--- a/compiler/rustc_passes/src/stability.rs
+++ b/compiler/rustc_passes/src/stability.rs
@@ -20,7 +20,7 @@ use rustc_hir::hir_id::CRATE_HIR_ID;
 use rustc_hir::intravisit::{self, Visitor};
 use rustc_hir::{FieldDef, Item, ItemKind, TraitRef, Ty, TyKind, Variant};
 use rustc_middle::hir::nested_filter;
-use rustc_middle::middle::privacy::AccessLevels;
+use rustc_middle::middle::privacy::EffectiveVisibilities;
 use rustc_middle::middle::stability::{AllowUnstable, DeprecationEntry, Index};
 use rustc_middle::ty::{query::Providers, TyCtxt};
 use rustc_session::lint;
@@ -378,7 +378,7 @@ impl<'a, 'tcx> Visitor<'tcx> for Annotator<'a, 'tcx> {
         }
 
         self.annotate(
-            i.def_id.def_id,
+            i.owner_id.def_id,
             i.span,
             fn_sig,
             kind,
@@ -397,7 +397,7 @@ impl<'a, 'tcx> Visitor<'tcx> for Annotator<'a, 'tcx> {
         };
 
         self.annotate(
-            ti.def_id.def_id,
+            ti.owner_id.def_id,
             ti.span,
             fn_sig,
             AnnotationKind::Required,
@@ -420,7 +420,7 @@ impl<'a, 'tcx> Visitor<'tcx> for Annotator<'a, 'tcx> {
         };
 
         self.annotate(
-            ii.def_id.def_id,
+            ii.owner_id.def_id,
             ii.span,
             fn_sig,
             kind,
@@ -478,7 +478,7 @@ impl<'a, 'tcx> Visitor<'tcx> for Annotator<'a, 'tcx> {
 
     fn visit_foreign_item(&mut self, i: &'tcx hir::ForeignItem<'tcx>) {
         self.annotate(
-            i.def_id.def_id,
+            i.owner_id.def_id,
             i.span,
             None,
             AnnotationKind::Required,
@@ -516,13 +516,16 @@ impl<'a, 'tcx> Visitor<'tcx> for Annotator<'a, 'tcx> {
 
 struct MissingStabilityAnnotations<'tcx> {
     tcx: TyCtxt<'tcx>,
-    access_levels: &'tcx AccessLevels,
+    effective_visibilities: &'tcx EffectiveVisibilities,
 }
 
 impl<'tcx> MissingStabilityAnnotations<'tcx> {
     fn check_missing_stability(&self, def_id: LocalDefId, span: Span) {
         let stab = self.tcx.stability().local_stability(def_id);
-        if !self.tcx.sess.opts.test && stab.is_none() && self.access_levels.is_reachable(def_id) {
+        if !self.tcx.sess.opts.test
+            && stab.is_none()
+            && self.effective_visibilities.is_reachable(def_id)
+        {
             let descr = self.tcx.def_kind(def_id).descr(def_id.to_def_id());
             self.tcx.sess.emit_err(MissingStabilityAttr { span, descr });
         }
@@ -533,6 +536,14 @@ impl<'tcx> MissingStabilityAnnotations<'tcx> {
             return;
         }
 
+        // if the const impl is derived using the `derive_const` attribute,
+        // then it would be "stable" at least for the impl.
+        // We gate usages of it using `feature(const_trait_impl)` anyways
+        // so there is no unstable leakage
+        if self.tcx.is_builtin_derive(def_id.to_def_id()) {
+            return;
+        }
+
         let is_const = self.tcx.is_const_fn(def_id.to_def_id())
             || self.tcx.is_const_trait_impl_raw(def_id.to_def_id());
         let is_stable = self
@@ -540,7 +551,7 @@ impl<'tcx> MissingStabilityAnnotations<'tcx> {
             .lookup_stability(def_id)
             .map_or(false, |stability| stability.level.is_stable());
         let missing_const_stability_attribute = self.tcx.lookup_const_stability(def_id).is_none();
-        let is_reachable = self.access_levels.is_reachable(def_id);
+        let is_reachable = self.effective_visibilities.is_reachable(def_id);
 
         if is_const && is_stable && missing_const_stability_attribute && is_reachable {
             let descr = self.tcx.def_kind(def_id).descr(def_id.to_def_id());
@@ -566,25 +577,25 @@ impl<'tcx> Visitor<'tcx> for MissingStabilityAnnotations<'tcx> {
             hir::ItemKind::Impl(hir::Impl { of_trait: None, .. })
                 | hir::ItemKind::ForeignMod { .. }
         ) {
-            self.check_missing_stability(i.def_id.def_id, i.span);
+            self.check_missing_stability(i.owner_id.def_id, i.span);
         }
 
         // Ensure stable `const fn` have a const stability attribute.
-        self.check_missing_const_stability(i.def_id.def_id, i.span);
+        self.check_missing_const_stability(i.owner_id.def_id, i.span);
 
         intravisit::walk_item(self, i)
     }
 
     fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem<'tcx>) {
-        self.check_missing_stability(ti.def_id.def_id, ti.span);
+        self.check_missing_stability(ti.owner_id.def_id, ti.span);
         intravisit::walk_trait_item(self, ti);
     }
 
     fn visit_impl_item(&mut self, ii: &'tcx hir::ImplItem<'tcx>) {
         let impl_def_id = self.tcx.hir().get_parent_item(ii.hir_id());
         if self.tcx.impl_trait_ref(impl_def_id).is_none() {
-            self.check_missing_stability(ii.def_id.def_id, ii.span);
-            self.check_missing_const_stability(ii.def_id.def_id, ii.span);
+            self.check_missing_stability(ii.owner_id.def_id, ii.span);
+            self.check_missing_const_stability(ii.owner_id.def_id, ii.span);
         }
         intravisit::walk_impl_item(self, ii);
     }
@@ -603,7 +614,7 @@ impl<'tcx> Visitor<'tcx> for MissingStabilityAnnotations<'tcx> {
     }
 
     fn visit_foreign_item(&mut self, i: &'tcx hir::ForeignItem<'tcx>) {
-        self.check_missing_stability(i.def_id.def_id, i.span);
+        self.check_missing_stability(i.owner_id.def_id, i.span);
         intravisit::walk_foreign_item(self, i);
     }
     // Note that we don't need to `check_missing_stability` for default generic parameters,
@@ -709,7 +720,7 @@ impl<'tcx> Visitor<'tcx> for Checker<'tcx> {
                     return;
                 }
 
-                let Some(cnum) = self.tcx.extern_mod_stmt_cnum(item.def_id.def_id) else {
+                let Some(cnum) = self.tcx.extern_mod_stmt_cnum(item.owner_id.def_id) else {
                     return;
                 };
                 let def_id = cnum.as_def_id();
@@ -762,7 +773,7 @@ impl<'tcx> Visitor<'tcx> for Checker<'tcx> {
                 }
 
                 for impl_item_ref in *items {
-                    let impl_item = self.tcx.associated_item(impl_item_ref.id.def_id);
+                    let impl_item = self.tcx.associated_item(impl_item_ref.id.owner_id);
 
                     if let Some(def_id) = impl_item.trait_item_def_id {
                         // Pass `None` to skip deprecation warnings.
@@ -919,8 +930,8 @@ pub fn check_unused_or_stable_features(tcx: TyCtxt<'_>) {
     let is_staged_api =
         tcx.sess.opts.unstable_opts.force_unstable_if_unmarked || tcx.features().staged_api;
     if is_staged_api {
-        let access_levels = &tcx.privacy_access_levels(());
-        let mut missing = MissingStabilityAnnotations { tcx, access_levels };
+        let effective_visibilities = &tcx.effective_visibilities(());
+        let mut missing = MissingStabilityAnnotations { tcx, effective_visibilities };
         missing.check_missing_stability(CRATE_DEF_ID, tcx.hir().span(CRATE_HIR_ID));
         tcx.hir().walk_toplevel_module(&mut missing);
         tcx.hir().visit_all_item_likes_in_crate(&mut missing);
diff --git a/compiler/rustc_passes/src/weak_lang_items.rs b/compiler/rustc_passes/src/weak_lang_items.rs
index 92024989a75e..f0815fcd8db9 100644
--- a/compiler/rustc_passes/src/weak_lang_items.rs
+++ b/compiler/rustc_passes/src/weak_lang_items.rs
@@ -2,15 +2,12 @@
 
 use rustc_data_structures::fx::FxHashSet;
 use rustc_hir::lang_items::{self, LangItem};
-use rustc_hir::weak_lang_items::WEAK_ITEMS_REFS;
+use rustc_hir::weak_lang_items::WEAK_LANG_ITEMS;
 use rustc_middle::middle::lang_items::required;
 use rustc_middle::ty::TyCtxt;
 use rustc_session::config::CrateType;
 
-use crate::errors::{
-    AllocFuncRequired, MissingAllocErrorHandler, MissingLangItem, MissingPanicHandler,
-    UnknownExternLangItem,
-};
+use crate::errors::{MissingLangItem, MissingPanicHandler, UnknownExternLangItem};
 
 /// Checks the crate for usage of weak lang items, returning a vector of all the
 /// language items required by this crate, but not defined yet.
@@ -29,12 +26,12 @@ pub fn check_crate<'tcx>(tcx: TyCtxt<'tcx>, items: &mut lang_items::LanguageItem
     for id in crate_items.foreign_items() {
         let attrs = tcx.hir().attrs(id.hir_id());
         if let Some((lang_item, _)) = lang_items::extract(attrs) {
-            if let Some(&item) = WEAK_ITEMS_REFS.get(&lang_item) {
-                if items.require(item).is_err() {
+            if let Some(item) = LangItem::from_name(lang_item) && item.is_weak() {
+                if items.get(item).is_none() {
                     items.missing.push(item);
                 }
             } else {
-                let span = tcx.def_span(id.def_id);
+                let span = tcx.def_span(id.owner_id);
                 tcx.sess.emit_err(UnknownExternLangItem { span, lang_item });
             }
         }
@@ -65,17 +62,12 @@ fn verify<'tcx>(tcx: TyCtxt<'tcx>, items: &lang_items::LanguageItems) {
         }
     }
 
-    for (name, &item) in WEAK_ITEMS_REFS.iter() {
-        if missing.contains(&item) && required(tcx, item) && items.require(item).is_err() {
+    for &item in WEAK_LANG_ITEMS.iter() {
+        if missing.contains(&item) && required(tcx, item) && items.get(item).is_none() {
             if item == LangItem::PanicImpl {
                 tcx.sess.emit_err(MissingPanicHandler);
-            } else if item == LangItem::Oom {
-                if !tcx.features().default_alloc_error_handler {
-                    tcx.sess.emit_err(AllocFuncRequired);
-                    tcx.sess.emit_note(MissingAllocErrorHandler);
-                }
             } else {
-                tcx.sess.emit_err(MissingLangItem { name: *name });
+                tcx.sess.emit_err(MissingLangItem { name: item.name() });
             }
         }
     }
diff --git a/compiler/rustc_privacy/src/lib.rs b/compiler/rustc_privacy/src/lib.rs
index 2636db6dbe1a..e17f85c1aae0 100644
--- a/compiler/rustc_privacy/src/lib.rs
+++ b/compiler/rustc_privacy/src/lib.rs
@@ -23,7 +23,7 @@ use rustc_hir::intravisit::{self, Visitor};
 use rustc_hir::{AssocItemKind, HirIdSet, ItemId, Node, PatKind};
 use rustc_middle::bug;
 use rustc_middle::hir::nested_filter;
-use rustc_middle::middle::privacy::{AccessLevel, AccessLevels};
+use rustc_middle::middle::privacy::{EffectiveVisibilities, Level};
 use rustc_middle::span_bug;
 use rustc_middle::ty::abstract_const::{walk_abstract_const, AbstractConst, Node as ACNode};
 use rustc_middle::ty::query::Providers;
@@ -310,7 +310,7 @@ fn min(vis1: ty::Visibility, vis2: ty::Visibility, tcx: TyCtxt<'_>) -> ty::Visib
 
 struct FindMin<'a, 'tcx, VL: VisibilityLike> {
     tcx: TyCtxt<'tcx>,
-    access_levels: &'a AccessLevels,
+    effective_visibilities: &'a EffectiveVisibilities,
     min: VL,
 }
 
@@ -344,8 +344,12 @@ trait VisibilityLike: Sized {
 
     // Returns an over-approximation (`skip_assoc_tys` = true) of visibility due to
     // associated types for which we can't determine visibility precisely.
-    fn of_impl(def_id: LocalDefId, tcx: TyCtxt<'_>, access_levels: &AccessLevels) -> Self {
-        let mut find = FindMin { tcx, access_levels, min: Self::MAX };
+    fn of_impl(
+        def_id: LocalDefId,
+        tcx: TyCtxt<'_>,
+        effective_visibilities: &EffectiveVisibilities,
+    ) -> Self {
+        let mut find = FindMin { tcx, effective_visibilities, min: Self::MAX };
         find.visit(tcx.type_of(def_id));
         if let Some(trait_ref) = tcx.impl_trait_ref(def_id) {
             find.visit_trait(trait_ref);
@@ -359,8 +363,8 @@ impl VisibilityLike for ty::Visibility {
         min(find.tcx.local_visibility(def_id), find.min, find.tcx)
     }
 }
-impl VisibilityLike for Option<AccessLevel> {
-    const MAX: Self = Some(AccessLevel::Public);
+impl VisibilityLike for Option<Level> {
+    const MAX: Self = Some(Level::Direct);
     // Type inference is very smart sometimes.
     // It can make an impl reachable even some components of its type or trait are unreachable.
     // E.g. methods of `impl ReachableTrait<UnreachableTy> for ReachableTy<UnreachableTy> { ... }`
@@ -372,7 +376,7 @@ impl VisibilityLike for Option<AccessLevel> {
     // (which require reaching the `DefId`s in them).
     const SHALLOW: bool = true;
     fn new_min(find: &FindMin<'_, '_, Self>, def_id: LocalDefId) -> Self {
-        cmp::min(find.access_levels.get_access_level(def_id), find.min)
+        cmp::min(find.effective_visibilities.public_at_level(def_id), find.min)
     }
 }
 
@@ -383,8 +387,8 @@ impl VisibilityLike for Option<AccessLevel> {
 struct EmbargoVisitor<'tcx> {
     tcx: TyCtxt<'tcx>,
 
-    /// Accessibility levels for reachable nodes.
-    access_levels: AccessLevels,
+    /// Effective visibilities for reachable nodes.
+    effective_visibilities: EffectiveVisibilities,
     /// A set of pairs corresponding to modules, where the first module is
     /// reachable via a macro that's defined in the second module. This cannot
     /// be represented as reachable because it can't handle the following case:
@@ -398,38 +402,34 @@ struct EmbargoVisitor<'tcx> {
     ///     n::p::f()
     /// }
     macro_reachable: FxHashSet<(LocalDefId, LocalDefId)>,
-    /// Previous accessibility level; `None` means unreachable.
-    prev_level: Option<AccessLevel>,
+    /// Previous visibility level; `None` means unreachable.
+    prev_level: Option<Level>,
     /// Has something changed in the level map?
     changed: bool,
 }
 
 struct ReachEverythingInTheInterfaceVisitor<'a, 'tcx> {
-    access_level: Option<AccessLevel>,
+    level: Option<Level>,
     item_def_id: LocalDefId,
     ev: &'a mut EmbargoVisitor<'tcx>,
 }
 
 impl<'tcx> EmbargoVisitor<'tcx> {
-    fn get(&self, def_id: LocalDefId) -> Option<AccessLevel> {
-        self.access_levels.get_access_level(def_id)
+    fn get(&self, def_id: LocalDefId) -> Option<Level> {
+        self.effective_visibilities.public_at_level(def_id)
     }
 
-    fn update_with_hir_id(
-        &mut self,
-        hir_id: hir::HirId,
-        level: Option<AccessLevel>,
-    ) -> Option<AccessLevel> {
+    fn update_with_hir_id(&mut self, hir_id: hir::HirId, level: Option<Level>) -> Option<Level> {
         let def_id = self.tcx.hir().local_def_id(hir_id);
         self.update(def_id, level)
     }
 
     /// Updates node level and returns the updated level.
-    fn update(&mut self, def_id: LocalDefId, level: Option<AccessLevel>) -> Option<AccessLevel> {
+    fn update(&mut self, def_id: LocalDefId, level: Option<Level>) -> Option<Level> {
         let old_level = self.get(def_id);
-        // Accessibility levels can only grow.
+        // Visibility levels can only grow.
         if level > old_level {
-            self.access_levels.set_access_level(
+            self.effective_visibilities.set_public_at_level(
                 def_id,
                 || ty::Visibility::Restricted(self.tcx.parent_module_from_def_id(def_id)),
                 level.unwrap(),
@@ -444,10 +444,10 @@ impl<'tcx> EmbargoVisitor<'tcx> {
     fn reach(
         &mut self,
         def_id: LocalDefId,
-        access_level: Option<AccessLevel>,
+        level: Option<Level>,
     ) -> ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
         ReachEverythingInTheInterfaceVisitor {
-            access_level: cmp::min(access_level, Some(AccessLevel::Reachable)),
+            level: cmp::min(level, Some(Level::Reachable)),
             item_def_id: def_id,
             ev: self,
         }
@@ -505,9 +505,9 @@ impl<'tcx> EmbargoVisitor<'tcx> {
     fn update_macro_reachable_mod(&mut self, module_def_id: LocalDefId, defining_mod: LocalDefId) {
         let module = self.tcx.hir().get_module(module_def_id).0;
         for item_id in module.item_ids {
-            let def_kind = self.tcx.def_kind(item_id.def_id);
-            let vis = self.tcx.local_visibility(item_id.def_id.def_id);
-            self.update_macro_reachable_def(item_id.def_id.def_id, def_kind, vis, defining_mod);
+            let def_kind = self.tcx.def_kind(item_id.owner_id);
+            let vis = self.tcx.local_visibility(item_id.owner_id.def_id);
+            self.update_macro_reachable_def(item_id.owner_id.def_id, def_kind, vis, defining_mod);
         }
         if let Some(exports) = self.tcx.module_reexports(module_def_id) {
             for export in exports {
@@ -530,7 +530,7 @@ impl<'tcx> EmbargoVisitor<'tcx> {
         vis: ty::Visibility,
         module: LocalDefId,
     ) {
-        let level = Some(AccessLevel::Reachable);
+        let level = Some(Level::Reachable);
         if vis.is_public() {
             self.update(def_id, level);
         }
@@ -627,14 +627,14 @@ impl<'tcx> Visitor<'tcx> for EmbargoVisitor<'tcx> {
     fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
         let item_level = match item.kind {
             hir::ItemKind::Impl { .. } => {
-                let impl_level = Option::<AccessLevel>::of_impl(
-                    item.def_id.def_id,
+                let impl_level = Option::<Level>::of_impl(
+                    item.owner_id.def_id,
                     self.tcx,
-                    &self.access_levels,
+                    &self.effective_visibilities,
                 );
-                self.update(item.def_id.def_id, impl_level)
+                self.update(item.owner_id.def_id, impl_level)
             }
-            _ => self.get(item.def_id.def_id),
+            _ => self.get(item.owner_id.def_id),
         };
 
         // Update levels of nested things.
@@ -653,15 +653,15 @@ impl<'tcx> Visitor<'tcx> for EmbargoVisitor<'tcx> {
             hir::ItemKind::Impl(ref impl_) => {
                 for impl_item_ref in impl_.items {
                     if impl_.of_trait.is_some()
-                        || self.tcx.visibility(impl_item_ref.id.def_id).is_public()
+                        || self.tcx.visibility(impl_item_ref.id.owner_id).is_public()
                     {
-                        self.update(impl_item_ref.id.def_id.def_id, item_level);
+                        self.update(impl_item_ref.id.owner_id.def_id, item_level);
                     }
                 }
             }
             hir::ItemKind::Trait(.., trait_item_refs) => {
                 for trait_item_ref in trait_item_refs {
-                    self.update(trait_item_ref.id.def_id.def_id, item_level);
+                    self.update(trait_item_ref.id.owner_id.def_id, item_level);
                 }
             }
             hir::ItemKind::Struct(ref def, _) | hir::ItemKind::Union(ref def, _) => {
@@ -677,12 +677,12 @@ impl<'tcx> Visitor<'tcx> for EmbargoVisitor<'tcx> {
                 }
             }
             hir::ItemKind::Macro(ref macro_def, _) => {
-                self.update_reachability_from_macro(item.def_id.def_id, macro_def);
+                self.update_reachability_from_macro(item.owner_id.def_id, macro_def);
             }
             hir::ItemKind::ForeignMod { items, .. } => {
                 for foreign_item in items {
-                    if self.tcx.visibility(foreign_item.id.def_id).is_public() {
-                        self.update(foreign_item.id.def_id.def_id, item_level);
+                    if self.tcx.visibility(foreign_item.id.owner_id).is_public() {
+                        self.update(foreign_item.id.owner_id.def_id, item_level);
                     }
                 }
             }
@@ -705,7 +705,7 @@ impl<'tcx> Visitor<'tcx> for EmbargoVisitor<'tcx> {
             hir::ItemKind::Macro(..) | hir::ItemKind::ExternCrate(..) => {}
             // All nested items are checked by `visit_item`.
             hir::ItemKind::Mod(..) => {}
-            // Handled in the access level of in rustc_resolve
+            // Handled in `rustc_resolve`.
             hir::ItemKind::Use(..) => {}
             // The interface is empty.
             hir::ItemKind::GlobalAsm(..) => {}
@@ -718,9 +718,8 @@ impl<'tcx> Visitor<'tcx> for EmbargoVisitor<'tcx> {
                     // FIXME: This is some serious pessimization intended to workaround deficiencies
                     // in the reachability pass (`middle/reachable.rs`). Types are marked as link-time
                     // reachable if they are returned via `impl Trait`, even from private functions.
-                    let exist_level =
-                        cmp::max(item_level, Some(AccessLevel::ReachableFromImplTrait));
-                    self.reach(item.def_id.def_id, exist_level).generics().predicates().ty();
+                    let exist_level = cmp::max(item_level, Some(Level::ReachableThroughImplTrait));
+                    self.reach(item.owner_id.def_id, exist_level).generics().predicates().ty();
                 }
             }
             // Visit everything.
@@ -729,20 +728,20 @@ impl<'tcx> Visitor<'tcx> for EmbargoVisitor<'tcx> {
             | hir::ItemKind::Fn(..)
             | hir::ItemKind::TyAlias(..) => {
                 if item_level.is_some() {
-                    self.reach(item.def_id.def_id, item_level).generics().predicates().ty();
+                    self.reach(item.owner_id.def_id, item_level).generics().predicates().ty();
                 }
             }
             hir::ItemKind::Trait(.., trait_item_refs) => {
                 if item_level.is_some() {
-                    self.reach(item.def_id.def_id, item_level).generics().predicates();
+                    self.reach(item.owner_id.def_id, item_level).generics().predicates();
 
                     for trait_item_ref in trait_item_refs {
                         let tcx = self.tcx;
-                        let mut reach = self.reach(trait_item_ref.id.def_id.def_id, item_level);
+                        let mut reach = self.reach(trait_item_ref.id.owner_id.def_id, item_level);
                         reach.generics().predicates();
 
                         if trait_item_ref.kind == AssocItemKind::Type
-                            && !tcx.impl_defaultness(trait_item_ref.id.def_id).has_value()
+                            && !tcx.impl_defaultness(trait_item_ref.id.owner_id).has_value()
                         {
                             // No type to visit.
                         } else {
@@ -753,22 +752,22 @@ impl<'tcx> Visitor<'tcx> for EmbargoVisitor<'tcx> {
             }
             hir::ItemKind::TraitAlias(..) => {
                 if item_level.is_some() {
-                    self.reach(item.def_id.def_id, item_level).generics().predicates();
+                    self.reach(item.owner_id.def_id, item_level).generics().predicates();
                 }
             }
             // Visit everything except for private impl items.
             hir::ItemKind::Impl(ref impl_) => {
                 if item_level.is_some() {
-                    self.reach(item.def_id.def_id, item_level)
+                    self.reach(item.owner_id.def_id, item_level)
                         .generics()
                         .predicates()
                         .ty()
                         .trait_ref();
 
                     for impl_item_ref in impl_.items {
-                        let impl_item_level = self.get(impl_item_ref.id.def_id.def_id);
+                        let impl_item_level = self.get(impl_item_ref.id.owner_id.def_id);
                         if impl_item_level.is_some() {
-                            self.reach(impl_item_ref.id.def_id.def_id, impl_item_level)
+                            self.reach(impl_item_ref.id.owner_id.def_id, impl_item_level)
                                 .generics()
                                 .predicates()
                                 .ty();
@@ -780,7 +779,7 @@ impl<'tcx> Visitor<'tcx> for EmbargoVisitor<'tcx> {
             // Visit everything, but enum variants have their own levels.
             hir::ItemKind::Enum(ref def, _) => {
                 if item_level.is_some() {
-                    self.reach(item.def_id.def_id, item_level).generics().predicates();
+                    self.reach(item.owner_id.def_id, item_level).generics().predicates();
                 }
                 for variant in def.variants {
                     let variant_level = self.get(self.tcx.hir().local_def_id(variant.id));
@@ -791,13 +790,13 @@ impl<'tcx> Visitor<'tcx> for EmbargoVisitor<'tcx> {
                         }
                         // Corner case: if the variant is reachable, but its
                         // enum is not, make the enum reachable as well.
-                        self.reach(item.def_id.def_id, variant_level).ty();
+                        self.reach(item.owner_id.def_id, variant_level).ty();
                     }
                     if let Some(hir_id) = variant.data.ctor_hir_id() {
                         let ctor_def_id = self.tcx.hir().local_def_id(hir_id);
                         let ctor_level = self.get(ctor_def_id);
                         if ctor_level.is_some() {
-                            self.reach(item.def_id.def_id, ctor_level).ty();
+                            self.reach(item.owner_id.def_id, ctor_level).ty();
                         }
                     }
                 }
@@ -805,9 +804,9 @@ impl<'tcx> Visitor<'tcx> for EmbargoVisitor<'tcx> {
             // Visit everything, but foreign items have their own levels.
             hir::ItemKind::ForeignMod { items, .. } => {
                 for foreign_item in items {
-                    let foreign_item_level = self.get(foreign_item.id.def_id.def_id);
+                    let foreign_item_level = self.get(foreign_item.id.owner_id.def_id);
                     if foreign_item_level.is_some() {
-                        self.reach(foreign_item.id.def_id.def_id, foreign_item_level)
+                        self.reach(foreign_item.id.owner_id.def_id, foreign_item_level)
                             .generics()
                             .predicates()
                             .ty();
@@ -817,7 +816,7 @@ impl<'tcx> Visitor<'tcx> for EmbargoVisitor<'tcx> {
             // Visit everything except for private fields.
             hir::ItemKind::Struct(ref struct_def, _) | hir::ItemKind::Union(ref struct_def, _) => {
                 if item_level.is_some() {
-                    self.reach(item.def_id.def_id, item_level).generics().predicates();
+                    self.reach(item.owner_id.def_id, item_level).generics().predicates();
                     for field in struct_def.fields() {
                         let def_id = self.tcx.hir().local_def_id(field.hir_id);
                         let field_level = self.get(def_id);
@@ -830,7 +829,7 @@ impl<'tcx> Visitor<'tcx> for EmbargoVisitor<'tcx> {
                     let ctor_def_id = self.tcx.hir().local_def_id(hir_id);
                     let ctor_level = self.get(ctor_def_id);
                     if ctor_level.is_some() {
-                        self.reach(item.def_id.def_id, ctor_level).ty();
+                        self.reach(item.owner_id.def_id, ctor_level).ty();
                     }
                 }
             }
@@ -901,10 +900,10 @@ impl<'tcx> DefIdVisitor<'tcx> for ReachEverythingInTheInterfaceVisitor<'_, 'tcx>
         _descr: &dyn fmt::Display,
     ) -> ControlFlow<Self::BreakTy> {
         if let Some(def_id) = def_id.as_local() {
-            if let (ty::Visibility::Public, _) | (_, Some(AccessLevel::ReachableFromImplTrait)) =
-                (self.tcx().visibility(def_id.to_def_id()), self.access_level)
+            if let (ty::Visibility::Public, _) | (_, Some(Level::ReachableThroughImplTrait)) =
+                (self.tcx().visibility(def_id.to_def_id()), self.level)
             {
-                self.ev.update(def_id, self.access_level);
+                self.ev.update(def_id, self.level);
             }
         }
         ControlFlow::CONTINUE
@@ -912,21 +911,21 @@ impl<'tcx> DefIdVisitor<'tcx> for ReachEverythingInTheInterfaceVisitor<'_, 'tcx>
 }
 
 ////////////////////////////////////////////////////////////////////////////////
-/// Visitor, used for AccessLevels table checking
+/// Visitor, used for EffectiveVisibilities table checking
 ////////////////////////////////////////////////////////////////////////////////
 pub struct TestReachabilityVisitor<'tcx, 'a> {
     tcx: TyCtxt<'tcx>,
-    access_levels: &'a AccessLevels,
+    effective_visibilities: &'a EffectiveVisibilities,
 }
 
 impl<'tcx, 'a> TestReachabilityVisitor<'tcx, 'a> {
-    fn access_level_diagnostic(&mut self, def_id: LocalDefId) {
+    fn effective_visibility_diagnostic(&mut self, def_id: LocalDefId) {
         if self.tcx.has_attr(def_id.to_def_id(), sym::rustc_effective_visibility) {
-            if let Some(effective_vis) = self.access_levels.get_effective_vis(def_id) {
-                let mut error_msg = String::new();
-                let span = self.tcx.def_span(def_id.to_def_id());
-                for level in AccessLevel::all_levels() {
-                    let vis_str = match effective_vis.get(level) {
+            let mut error_msg = String::new();
+            let span = self.tcx.def_span(def_id.to_def_id());
+            if let Some(effective_vis) = self.effective_visibilities.effective_vis(def_id) {
+                for level in Level::all_levels() {
+                    let vis_str = match effective_vis.at_level(level) {
                         ty::Visibility::Restricted(restricted_id) => {
                             if restricted_id.is_top_level_module() {
                                 "pub(crate)".to_string()
@@ -938,36 +937,46 @@ impl<'tcx, 'a> TestReachabilityVisitor<'tcx, 'a> {
                         }
                         ty::Visibility::Public => "pub".to_string(),
                     };
-                    if level != AccessLevel::Public {
+                    if level != Level::Direct {
                         error_msg.push_str(", ");
                     }
                     error_msg.push_str(&format!("{:?}: {}", level, vis_str));
                 }
-                self.tcx.sess.emit_err(ReportEffectiveVisibility { span, descr: error_msg });
+            } else {
+                error_msg.push_str("not in the table");
             }
+            self.tcx.sess.emit_err(ReportEffectiveVisibility { span, descr: error_msg });
         }
     }
 }
 
 impl<'tcx, 'a> Visitor<'tcx> for TestReachabilityVisitor<'tcx, 'a> {
     fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
-        self.access_level_diagnostic(item.def_id.def_id);
+        self.effective_visibility_diagnostic(item.owner_id.def_id);
 
         match item.kind {
             hir::ItemKind::Enum(ref def, _) => {
                 for variant in def.variants.iter() {
                     let variant_id = self.tcx.hir().local_def_id(variant.id);
-                    self.access_level_diagnostic(variant_id);
+                    self.effective_visibility_diagnostic(variant_id);
+                    if let Some(ctor_hir_id) = variant.data.ctor_hir_id() {
+                        let ctor_def_id = self.tcx.hir().local_def_id(ctor_hir_id);
+                        self.effective_visibility_diagnostic(ctor_def_id);
+                    }
                     for field in variant.data.fields() {
                         let def_id = self.tcx.hir().local_def_id(field.hir_id);
-                        self.access_level_diagnostic(def_id);
+                        self.effective_visibility_diagnostic(def_id);
                     }
                 }
             }
             hir::ItemKind::Struct(ref def, _) | hir::ItemKind::Union(ref def, _) => {
+                if let Some(ctor_hir_id) = def.ctor_hir_id() {
+                    let ctor_def_id = self.tcx.hir().local_def_id(ctor_hir_id);
+                    self.effective_visibility_diagnostic(ctor_def_id);
+                }
                 for field in def.fields() {
                     let def_id = self.tcx.hir().local_def_id(field.hir_id);
-                    self.access_level_diagnostic(def_id);
+                    self.effective_visibility_diagnostic(def_id);
                 }
             }
             _ => {}
@@ -975,13 +984,13 @@ impl<'tcx, 'a> Visitor<'tcx> for TestReachabilityVisitor<'tcx, 'a> {
     }
 
     fn visit_trait_item(&mut self, item: &'tcx hir::TraitItem<'tcx>) {
-        self.access_level_diagnostic(item.def_id.def_id);
+        self.effective_visibility_diagnostic(item.owner_id.def_id);
     }
     fn visit_impl_item(&mut self, item: &'tcx hir::ImplItem<'tcx>) {
-        self.access_level_diagnostic(item.def_id.def_id);
+        self.effective_visibility_diagnostic(item.owner_id.def_id);
     }
     fn visit_foreign_item(&mut self, item: &'tcx hir::ForeignItem<'tcx>) {
-        self.access_level_diagnostic(item.def_id.def_id);
+        self.effective_visibility_diagnostic(item.owner_id.def_id);
     }
 }
 
@@ -1052,7 +1061,7 @@ impl<'tcx> Visitor<'tcx> for NamePrivacyVisitor<'tcx> {
 
     fn visit_mod(&mut self, _m: &'tcx hir::Mod<'tcx>, _s: Span, _n: hir::HirId) {
         // Don't visit nested modules, since we run a separate visitor walk
-        // for each module in `privacy_access_levels`
+        // for each module in `effective_visibilities`
     }
 
     fn visit_nested_body(&mut self, body: hir::BodyId) {
@@ -1064,7 +1073,7 @@ impl<'tcx> Visitor<'tcx> for NamePrivacyVisitor<'tcx> {
     }
 
     fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
-        let orig_current_item = mem::replace(&mut self.current_item, item.def_id.def_id);
+        let orig_current_item = mem::replace(&mut self.current_item, item.owner_id.def_id);
         intravisit::walk_item(self, item);
         self.current_item = orig_current_item;
     }
@@ -1177,7 +1186,7 @@ impl<'tcx> Visitor<'tcx> for TypePrivacyVisitor<'tcx> {
 
     fn visit_mod(&mut self, _m: &'tcx hir::Mod<'tcx>, _s: Span, _n: hir::HirId) {
         // Don't visit nested modules, since we run a separate visitor walk
-        // for each module in `privacy_access_levels`
+        // for each module in `effective_visibilities`
     }
 
     fn visit_nested_body(&mut self, body: hir::BodyId) {
@@ -1367,7 +1376,7 @@ impl<'tcx> Visitor<'tcx> for TypePrivacyVisitor<'tcx> {
 
     // Check types in item interfaces.
     fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
-        let orig_current_item = mem::replace(&mut self.current_item, item.def_id.def_id);
+        let orig_current_item = mem::replace(&mut self.current_item, item.owner_id.def_id);
         let old_maybe_typeck_results = self.maybe_typeck_results.take();
         intravisit::walk_item(self, item);
         self.maybe_typeck_results = old_maybe_typeck_results;
@@ -1402,7 +1411,7 @@ impl<'tcx> DefIdVisitor<'tcx> for TypePrivacyVisitor<'tcx> {
 
 struct ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
     tcx: TyCtxt<'tcx>,
-    access_levels: &'a AccessLevels,
+    effective_visibilities: &'a EffectiveVisibilities,
     in_variant: bool,
     // Set of errors produced by this obsolete visitor.
     old_error_set: HirIdSet,
@@ -1445,7 +1454,7 @@ impl<'a, 'tcx> ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
     fn trait_is_public(&self, trait_id: LocalDefId) -> bool {
         // FIXME: this would preferably be using `exported_items`, but all
         // traits are exported currently (see `EmbargoVisitor.exported_trait`).
-        self.access_levels.is_public(trait_id)
+        self.effective_visibilities.is_directly_public(trait_id)
     }
 
     fn check_generic_bound(&mut self, bound: &hir::GenericBound<'_>) {
@@ -1457,7 +1466,7 @@ impl<'a, 'tcx> ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
     }
 
     fn item_is_public(&self, def_id: LocalDefId) -> bool {
-        self.access_levels.is_reachable(def_id) || self.tcx.visibility(def_id).is_public()
+        self.effective_visibilities.is_reachable(def_id) || self.tcx.visibility(def_id).is_public()
     }
 }
 
@@ -1511,7 +1520,7 @@ impl<'a, 'tcx> Visitor<'tcx> for ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
             hir::ItemKind::ForeignMod { .. } => {}
 
             hir::ItemKind::Trait(.., bounds, _) => {
-                if !self.trait_is_public(item.def_id.def_id) {
+                if !self.trait_is_public(item.owner_id.def_id) {
                     return;
                 }
 
@@ -1571,9 +1580,9 @@ impl<'a, 'tcx> Visitor<'tcx> for ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
                     || impl_.items.iter().any(|impl_item_ref| {
                         let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
                         match impl_item.kind {
-                            hir::ImplItemKind::Const(..) | hir::ImplItemKind::Fn(..) => {
-                                self.access_levels.is_reachable(impl_item_ref.id.def_id.def_id)
-                            }
+                            hir::ImplItemKind::Const(..) | hir::ImplItemKind::Fn(..) => self
+                                .effective_visibilities
+                                .is_reachable(impl_item_ref.id.owner_id.def_id),
                             hir::ImplItemKind::Type(_) => false,
                         }
                     });
@@ -1592,7 +1601,7 @@ impl<'a, 'tcx> Visitor<'tcx> for ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
                                 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
                                 match impl_item.kind {
                                     hir::ImplItemKind::Const(..) | hir::ImplItemKind::Fn(..)
-                                        if self.item_is_public(impl_item.def_id.def_id) =>
+                                        if self.item_is_public(impl_item.owner_id.def_id) =>
                                     {
                                         intravisit::walk_impl_item(self, impl_item)
                                     }
@@ -1633,8 +1642,10 @@ impl<'a, 'tcx> Visitor<'tcx> for ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
                     // methods will be visible as `Public::foo`.
                     let mut found_pub_static = false;
                     for impl_item_ref in impl_.items {
-                        if self.access_levels.is_reachable(impl_item_ref.id.def_id.def_id)
-                            || self.tcx.visibility(impl_item_ref.id.def_id).is_public()
+                        if self
+                            .effective_visibilities
+                            .is_reachable(impl_item_ref.id.owner_id.def_id)
+                            || self.tcx.visibility(impl_item_ref.id.owner_id).is_public()
                         {
                             let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
                             match impl_item_ref.kind {
@@ -1662,7 +1673,7 @@ impl<'a, 'tcx> Visitor<'tcx> for ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
             hir::ItemKind::TyAlias(..) => return,
 
             // Not at all public, so we don't care.
-            _ if !self.item_is_public(item.def_id.def_id) => {
+            _ if !self.item_is_public(item.owner_id.def_id) => {
                 return;
             }
 
@@ -1693,7 +1704,7 @@ impl<'a, 'tcx> Visitor<'tcx> for ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
     }
 
     fn visit_foreign_item(&mut self, item: &'tcx hir::ForeignItem<'tcx>) {
-        if self.access_levels.is_reachable(item.def_id.def_id) {
+        if self.effective_visibilities.is_reachable(item.owner_id.def_id) {
             intravisit::walk_foreign_item(self, item)
         }
     }
@@ -1708,7 +1719,7 @@ impl<'a, 'tcx> Visitor<'tcx> for ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
     }
 
     fn visit_variant(&mut self, v: &'tcx hir::Variant<'tcx>) {
-        if self.access_levels.is_reachable(self.tcx.hir().local_def_id(v.id)) {
+        if self.effective_visibilities.is_reachable(self.tcx.hir().local_def_id(v.id)) {
             self.in_variant = true;
             intravisit::walk_variant(self, v);
             self.in_variant = false;
@@ -1930,7 +1941,7 @@ impl<'tcx> PrivateItemsInPublicInterfacesChecker<'tcx> {
 
     pub fn check_item(&mut self, id: ItemId) {
         let tcx = self.tcx;
-        let def_id = id.def_id.def_id;
+        let def_id = id.owner_id.def_id;
         let item_visibility = tcx.local_visibility(def_id);
         let def_kind = tcx.def_kind(def_id);
 
@@ -1946,17 +1957,17 @@ impl<'tcx> PrivateItemsInPublicInterfacesChecker<'tcx> {
             DefKind::Trait => {
                 let item = tcx.hir().item(id);
                 if let hir::ItemKind::Trait(.., trait_item_refs) = item.kind {
-                    self.check(item.def_id.def_id, item_visibility).generics().predicates();
+                    self.check(item.owner_id.def_id, item_visibility).generics().predicates();
 
                     for trait_item_ref in trait_item_refs {
                         self.check_assoc_item(
-                            trait_item_ref.id.def_id.def_id,
+                            trait_item_ref.id.owner_id.def_id,
                             trait_item_ref.kind,
                             item_visibility,
                         );
 
                         if let AssocItemKind::Type = trait_item_ref.kind {
-                            self.check(trait_item_ref.id.def_id.def_id, item_visibility).bounds();
+                            self.check(trait_item_ref.id.owner_id.def_id, item_visibility).bounds();
                         }
                     }
                 }
@@ -1967,7 +1978,7 @@ impl<'tcx> PrivateItemsInPublicInterfacesChecker<'tcx> {
             DefKind::Enum => {
                 let item = tcx.hir().item(id);
                 if let hir::ItemKind::Enum(ref def, _) = item.kind {
-                    self.check(item.def_id.def_id, item_visibility).generics().predicates();
+                    self.check(item.owner_id.def_id, item_visibility).generics().predicates();
 
                     for variant in def.variants {
                         for field in variant.data.fields() {
@@ -1982,8 +1993,11 @@ impl<'tcx> PrivateItemsInPublicInterfacesChecker<'tcx> {
                 let item = tcx.hir().item(id);
                 if let hir::ItemKind::ForeignMod { items, .. } = item.kind {
                     for foreign_item in items {
-                        let vis = tcx.local_visibility(foreign_item.id.def_id.def_id);
-                        self.check(foreign_item.id.def_id.def_id, vis).generics().predicates().ty();
+                        let vis = tcx.local_visibility(foreign_item.id.owner_id.def_id);
+                        self.check(foreign_item.id.owner_id.def_id, vis)
+                            .generics()
+                            .predicates()
+                            .ty();
                     }
                 }
             }
@@ -1993,7 +2007,7 @@ impl<'tcx> PrivateItemsInPublicInterfacesChecker<'tcx> {
                 if let hir::ItemKind::Struct(ref struct_def, _)
                 | hir::ItemKind::Union(ref struct_def, _) = item.kind
                 {
-                    self.check(item.def_id.def_id, item_visibility).generics().predicates();
+                    self.check(item.owner_id.def_id, item_visibility).generics().predicates();
 
                     for field in struct_def.fields() {
                         let def_id = tcx.hir().local_def_id(field.hir_id);
@@ -2010,20 +2024,24 @@ impl<'tcx> PrivateItemsInPublicInterfacesChecker<'tcx> {
                 let item = tcx.hir().item(id);
                 if let hir::ItemKind::Impl(ref impl_) = item.kind {
                     let impl_vis =
-                        ty::Visibility::of_impl(item.def_id.def_id, tcx, &Default::default());
+                        ty::Visibility::of_impl(item.owner_id.def_id, tcx, &Default::default());
                     // check that private components do not appear in the generics or predicates of inherent impls
                     // this check is intentionally NOT performed for impls of traits, per #90586
                     if impl_.of_trait.is_none() {
-                        self.check(item.def_id.def_id, impl_vis).generics().predicates();
+                        self.check(item.owner_id.def_id, impl_vis).generics().predicates();
                     }
                     for impl_item_ref in impl_.items {
                         let impl_item_vis = if impl_.of_trait.is_none() {
-                            min(tcx.local_visibility(impl_item_ref.id.def_id.def_id), impl_vis, tcx)
+                            min(
+                                tcx.local_visibility(impl_item_ref.id.owner_id.def_id),
+                                impl_vis,
+                                tcx,
+                            )
                         } else {
                             impl_vis
                         };
                         self.check_assoc_item(
-                            impl_item_ref.id.def_id.def_id,
+                            impl_item_ref.id.owner_id.def_id,
                             impl_item_ref.kind,
                             impl_item_vis,
                         );
@@ -2038,7 +2056,7 @@ impl<'tcx> PrivateItemsInPublicInterfacesChecker<'tcx> {
 pub fn provide(providers: &mut Providers) {
     *providers = Providers {
         visibility,
-        privacy_access_levels,
+        effective_visibilities,
         check_private_in_public,
         check_mod_privacy,
         ..*providers
@@ -2110,17 +2128,18 @@ fn check_mod_privacy(tcx: TyCtxt<'_>, module_def_id: LocalDefId) {
     intravisit::walk_mod(&mut visitor, module, hir_id);
 }
 
-fn privacy_access_levels(tcx: TyCtxt<'_>, (): ()) -> &AccessLevels {
+fn effective_visibilities(tcx: TyCtxt<'_>, (): ()) -> &EffectiveVisibilities {
     // Build up a set of all exported items in the AST. This is a set of all
     // items which are reachable from external crates based on visibility.
     let mut visitor = EmbargoVisitor {
         tcx,
-        access_levels: tcx.resolutions(()).access_levels.clone(),
+        effective_visibilities: tcx.resolutions(()).effective_visibilities.clone(),
         macro_reachable: Default::default(),
-        prev_level: Some(AccessLevel::Public),
+        prev_level: Some(Level::Direct),
         changed: false,
     };
 
+    visitor.effective_visibilities.check_invariants(tcx, true);
     loop {
         tcx.hir().walk_toplevel_module(&mut visitor);
         if visitor.changed {
@@ -2129,19 +2148,21 @@ fn privacy_access_levels(tcx: TyCtxt<'_>, (): ()) -> &AccessLevels {
             break;
         }
     }
+    visitor.effective_visibilities.check_invariants(tcx, false);
 
-    let mut check_visitor = TestReachabilityVisitor { tcx, access_levels: &visitor.access_levels };
+    let mut check_visitor =
+        TestReachabilityVisitor { tcx, effective_visibilities: &visitor.effective_visibilities };
     tcx.hir().visit_all_item_likes_in_crate(&mut check_visitor);
 
-    tcx.arena.alloc(visitor.access_levels)
+    tcx.arena.alloc(visitor.effective_visibilities)
 }
 
 fn check_private_in_public(tcx: TyCtxt<'_>, (): ()) {
-    let access_levels = tcx.privacy_access_levels(());
+    let effective_visibilities = tcx.effective_visibilities(());
 
     let mut visitor = ObsoleteVisiblePrivateTypesVisitor {
         tcx,
-        access_levels,
+        effective_visibilities,
         in_variant: false,
         old_error_set: Default::default(),
     };
diff --git a/compiler/rustc_query_impl/Cargo.toml b/compiler/rustc_query_impl/Cargo.toml
index e7f12caaf33e..b2111a1262a3 100644
--- a/compiler/rustc_query_impl/Cargo.toml
+++ b/compiler/rustc_query_impl/Cargo.toml
@@ -21,7 +21,7 @@ rustc_serialize = { path = "../rustc_serialize" }
 rustc_session = { path = "../rustc_session" }
 rustc_span = { path = "../rustc_span" }
 rustc_target = { path = "../rustc_target" }
-thin-vec = "0.2.8"
+thin-vec = "0.2.9"
 tracing = "0.1"
 
 [features]
diff --git a/compiler/rustc_query_impl/src/lib.rs b/compiler/rustc_query_impl/src/lib.rs
index 11d4c97e71ca..18cb0e0ca0b1 100644
--- a/compiler/rustc_query_impl/src/lib.rs
+++ b/compiler/rustc_query_impl/src/lib.rs
@@ -36,7 +36,7 @@ mod keys;
 use keys::Key;
 
 pub use rustc_query_system::query::QueryConfig;
-pub(crate) use rustc_query_system::query::{QueryDescription, QueryVTable};
+pub(crate) use rustc_query_system::query::QueryVTable;
 
 mod on_disk_cache;
 pub use on_disk_cache::OnDiskCache;
diff --git a/compiler/rustc_query_impl/src/on_disk_cache.rs b/compiler/rustc_query_impl/src/on_disk_cache.rs
index a59216501127..eaed9aeb8502 100644
--- a/compiler/rustc_query_impl/src/on_disk_cache.rs
+++ b/compiler/rustc_query_impl/src/on_disk_cache.rs
@@ -1,8 +1,9 @@
 use crate::QueryCtxt;
-use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexSet};
+use rustc_data_structures::fx::{FxHashMap, FxIndexSet};
 use rustc_data_structures::memmap::Mmap;
 use rustc_data_structures::sync::{HashMapExt, Lock, Lrc, RwLock};
 use rustc_data_structures::unhash::UnhashMap;
+use rustc_data_structures::unord::UnordSet;
 use rustc_hir::def_id::{CrateNum, DefId, DefIndex, LocalDefId, StableCrateId, LOCAL_CRATE};
 use rustc_hir::definitions::DefPathHash;
 use rustc_index::vec::{Idx, IndexVec};
@@ -118,12 +119,11 @@ pub type EncodedDepNodeIndex = Vec<(SerializedDepNodeIndex, AbsoluteBytePos)>;
 struct SourceFileIndex(u32);
 
 #[derive(Copy, Clone, Debug, Hash, Eq, PartialEq, Encodable, Decodable)]
-pub struct AbsoluteBytePos(u32);
+pub struct AbsoluteBytePos(u64);
 
 impl AbsoluteBytePos {
     fn new(pos: usize) -> AbsoluteBytePos {
-        debug_assert!(pos <= u32::MAX as usize);
-        AbsoluteBytePos(pos as u32)
+        AbsoluteBytePos(pos.try_into().expect("Incremental cache file size overflowed u64."))
     }
 
     fn to_usize(self) -> usize {
@@ -792,7 +792,7 @@ impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for DefId {
     }
 }
 
-impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for &'tcx FxHashSet<LocalDefId> {
+impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for &'tcx UnordSet<LocalDefId> {
     fn decode(d: &mut CacheDecoder<'a, 'tcx>) -> Self {
         RefDecodable::decode(d)
     }
@@ -1062,7 +1062,7 @@ pub fn encode_query_results<'a, 'tcx, CTX, Q>(
     query_result_index: &mut EncodedDepNodeIndex,
 ) where
     CTX: QueryContext + 'tcx,
-    Q: super::QueryDescription<CTX>,
+    Q: super::QueryConfig<CTX>,
     Q::Value: Encodable<CacheEncoder<'a, 'tcx>>,
 {
     let _timer = tcx
diff --git a/compiler/rustc_query_impl/src/plumbing.rs b/compiler/rustc_query_impl/src/plumbing.rs
index 1d17f4221969..992e777904e6 100644
--- a/compiler/rustc_query_impl/src/plumbing.rs
+++ b/compiler/rustc_query_impl/src/plumbing.rs
@@ -17,8 +17,7 @@ use rustc_middle::ty::{self, TyCtxt};
 use rustc_query_system::dep_graph::{DepNodeParams, HasDepContext};
 use rustc_query_system::ich::StableHashingContext;
 use rustc_query_system::query::{
-    force_query, QueryConfig, QueryContext, QueryDescription, QueryJobId, QueryMap,
-    QuerySideEffects, QueryStackFrame,
+    force_query, QueryConfig, QueryContext, QueryJobId, QueryMap, QuerySideEffects, QueryStackFrame,
 };
 use rustc_query_system::{LayoutOfDepth, QueryOverflow, Value};
 use rustc_serialize::Decodable;
@@ -340,7 +339,7 @@ pub(crate) fn create_query_frame<
 
 fn try_load_from_on_disk_cache<'tcx, Q>(tcx: TyCtxt<'tcx>, dep_node: DepNode)
 where
-    Q: QueryDescription<QueryCtxt<'tcx>>,
+    Q: QueryConfig<QueryCtxt<'tcx>>,
     Q::Key: DepNodeParams<TyCtxt<'tcx>>,
 {
     debug_assert!(tcx.dep_graph.is_green(&dep_node));
@@ -365,7 +364,7 @@ where
 
 fn force_from_dep_node<'tcx, Q>(tcx: TyCtxt<'tcx>, dep_node: DepNode) -> bool
 where
-    Q: QueryDescription<QueryCtxt<'tcx>>,
+    Q: QueryConfig<QueryCtxt<'tcx>>,
     Q::Key: DepNodeParams<TyCtxt<'tcx>>,
     Q::Value: Value<TyCtxt<'tcx>>,
 {
@@ -398,12 +397,9 @@ where
     }
 }
 
-pub(crate) fn query_callback<'tcx, Q: QueryConfig>(
-    is_anon: bool,
-    is_eval_always: bool,
-) -> DepKindStruct<'tcx>
+pub(crate) fn query_callback<'tcx, Q>(is_anon: bool, is_eval_always: bool) -> DepKindStruct<'tcx>
 where
-    Q: QueryDescription<QueryCtxt<'tcx>>,
+    Q: QueryConfig<QueryCtxt<'tcx>>,
     Q::Key: DepNodeParams<TyCtxt<'tcx>>,
 {
     let fingerprint_style = Q::Key::fingerprint_style();
@@ -458,14 +454,12 @@ macro_rules! define_queries {
             })*
         }
 
-        $(impl<'tcx> QueryConfig for queries::$name<'tcx> {
+        $(impl<'tcx> QueryConfig<QueryCtxt<'tcx>> for queries::$name<'tcx> {
             type Key = query_keys::$name<'tcx>;
             type Value = query_values::$name<'tcx>;
             type Stored = query_stored::$name<'tcx>;
             const NAME: &'static str = stringify!($name);
-        }
 
-        impl<'tcx> QueryDescription<QueryCtxt<'tcx>> for queries::$name<'tcx> {
             #[inline]
             fn cache_on_disk(tcx: TyCtxt<'tcx>, key: &Self::Key) -> bool {
                 ::rustc_middle::query::cached::$name(tcx, key)
@@ -662,12 +656,15 @@ macro_rules! define_queries_struct {
             local_providers: Box<Providers>,
             extern_providers: Box<ExternProviders>,
             query_structs: Vec<$crate::plumbing::QueryStruct<'tcx>>,
-
             pub on_disk_cache: Option<OnDiskCache<'tcx>>,
-
             jobs: AtomicU64,
 
-            $($(#[$attr])*  $name: QueryState<<queries::$name<'tcx> as QueryConfig>::Key>,)*
+            $(
+                $(#[$attr])*
+                $name: QueryState<
+                    <queries::$name<'tcx> as QueryConfig<QueryCtxt<'tcx>>>::Key
+                >,
+            )*
         }
 
         impl<'tcx> Queries<'tcx> {
@@ -704,7 +701,7 @@ macro_rules! define_queries_struct {
                 &'tcx self,
                 tcx: TyCtxt<'tcx>,
                 span: Span,
-                key: <queries::$name<'tcx> as QueryConfig>::Key,
+                key: <queries::$name<'tcx> as QueryConfig<QueryCtxt<'tcx>>>::Key,
                 mode: QueryMode,
             ) -> Option<query_stored::$name<'tcx>> {
                 let qcx = QueryCtxt { tcx, queries: self };
diff --git a/compiler/rustc_query_impl/src/profiling_support.rs b/compiler/rustc_query_impl/src/profiling_support.rs
index 2cc311d48c8f..81114f2cd82c 100644
--- a/compiler/rustc_query_impl/src/profiling_support.rs
+++ b/compiler/rustc_query_impl/src/profiling_support.rs
@@ -19,18 +19,18 @@ impl QueryKeyStringCache {
     }
 }
 
-struct QueryKeyStringBuilder<'p, 'c, 'tcx> {
+struct QueryKeyStringBuilder<'p, 'tcx> {
     profiler: &'p SelfProfiler,
     tcx: TyCtxt<'tcx>,
-    string_cache: &'c mut QueryKeyStringCache,
+    string_cache: &'p mut QueryKeyStringCache,
 }
 
-impl<'p, 'c, 'tcx> QueryKeyStringBuilder<'p, 'c, 'tcx> {
+impl<'p, 'tcx> QueryKeyStringBuilder<'p, 'tcx> {
     fn new(
         profiler: &'p SelfProfiler,
         tcx: TyCtxt<'tcx>,
-        string_cache: &'c mut QueryKeyStringCache,
-    ) -> QueryKeyStringBuilder<'p, 'c, 'tcx> {
+        string_cache: &'p mut QueryKeyStringCache,
+    ) -> QueryKeyStringBuilder<'p, 'tcx> {
         QueryKeyStringBuilder { profiler, tcx, string_cache }
     }
 
@@ -99,7 +99,7 @@ impl<'p, 'c, 'tcx> QueryKeyStringBuilder<'p, 'c, 'tcx> {
 }
 
 trait IntoSelfProfilingString {
-    fn to_self_profile_string(&self, builder: &mut QueryKeyStringBuilder<'_, '_, '_>) -> StringId;
+    fn to_self_profile_string(&self, builder: &mut QueryKeyStringBuilder<'_, '_>) -> StringId;
 }
 
 // The default implementation of `IntoSelfProfilingString` just uses `Debug`
@@ -109,7 +109,7 @@ trait IntoSelfProfilingString {
 impl<T: Debug> IntoSelfProfilingString for T {
     default fn to_self_profile_string(
         &self,
-        builder: &mut QueryKeyStringBuilder<'_, '_, '_>,
+        builder: &mut QueryKeyStringBuilder<'_, '_>,
     ) -> StringId {
         let s = format!("{:?}", self);
         builder.profiler.alloc_string(&s[..])
@@ -117,60 +117,42 @@ impl<T: Debug> IntoSelfProfilingString for T {
 }
 
 impl<T: SpecIntoSelfProfilingString> IntoSelfProfilingString for T {
-    fn to_self_profile_string(&self, builder: &mut QueryKeyStringBuilder<'_, '_, '_>) -> StringId {
+    fn to_self_profile_string(&self, builder: &mut QueryKeyStringBuilder<'_, '_>) -> StringId {
         self.spec_to_self_profile_string(builder)
     }
 }
 
 #[rustc_specialization_trait]
 trait SpecIntoSelfProfilingString: Debug {
-    fn spec_to_self_profile_string(
-        &self,
-        builder: &mut QueryKeyStringBuilder<'_, '_, '_>,
-    ) -> StringId;
+    fn spec_to_self_profile_string(&self, builder: &mut QueryKeyStringBuilder<'_, '_>) -> StringId;
 }
 
 impl SpecIntoSelfProfilingString for DefId {
-    fn spec_to_self_profile_string(
-        &self,
-        builder: &mut QueryKeyStringBuilder<'_, '_, '_>,
-    ) -> StringId {
+    fn spec_to_self_profile_string(&self, builder: &mut QueryKeyStringBuilder<'_, '_>) -> StringId {
         builder.def_id_to_string_id(*self)
     }
 }
 
 impl SpecIntoSelfProfilingString for CrateNum {
-    fn spec_to_self_profile_string(
-        &self,
-        builder: &mut QueryKeyStringBuilder<'_, '_, '_>,
-    ) -> StringId {
+    fn spec_to_self_profile_string(&self, builder: &mut QueryKeyStringBuilder<'_, '_>) -> StringId {
         builder.def_id_to_string_id(self.as_def_id())
     }
 }
 
 impl SpecIntoSelfProfilingString for DefIndex {
-    fn spec_to_self_profile_string(
-        &self,
-        builder: &mut QueryKeyStringBuilder<'_, '_, '_>,
-    ) -> StringId {
+    fn spec_to_self_profile_string(&self, builder: &mut QueryKeyStringBuilder<'_, '_>) -> StringId {
         builder.def_id_to_string_id(DefId { krate: LOCAL_CRATE, index: *self })
     }
 }
 
 impl SpecIntoSelfProfilingString for LocalDefId {
-    fn spec_to_self_profile_string(
-        &self,
-        builder: &mut QueryKeyStringBuilder<'_, '_, '_>,
-    ) -> StringId {
+    fn spec_to_self_profile_string(&self, builder: &mut QueryKeyStringBuilder<'_, '_>) -> StringId {
         builder.def_id_to_string_id(DefId { krate: LOCAL_CRATE, index: self.local_def_index })
     }
 }
 
 impl<T: SpecIntoSelfProfilingString> SpecIntoSelfProfilingString for WithOptConstParam<T> {
-    fn spec_to_self_profile_string(
-        &self,
-        builder: &mut QueryKeyStringBuilder<'_, '_, '_>,
-    ) -> StringId {
+    fn spec_to_self_profile_string(&self, builder: &mut QueryKeyStringBuilder<'_, '_>) -> StringId {
         // We print `WithOptConstParam` values as tuples to make them shorter
         // and more readable, without losing information:
         //
@@ -205,10 +187,7 @@ where
     T0: SpecIntoSelfProfilingString,
     T1: SpecIntoSelfProfilingString,
 {
-    fn spec_to_self_profile_string(
-        &self,
-        builder: &mut QueryKeyStringBuilder<'_, '_, '_>,
-    ) -> StringId {
+    fn spec_to_self_profile_string(&self, builder: &mut QueryKeyStringBuilder<'_, '_>) -> StringId {
         let val0 = self.0.to_self_profile_string(builder);
         let val1 = self.1.to_self_profile_string(builder);
 
diff --git a/compiler/rustc_query_system/Cargo.toml b/compiler/rustc_query_system/Cargo.toml
index faddad741710..028756b5a0a1 100644
--- a/compiler/rustc_query_system/Cargo.toml
+++ b/compiler/rustc_query_system/Cargo.toml
@@ -22,7 +22,7 @@ rustc_span = { path = "../rustc_span" }
 rustc_target = { path = "../rustc_target" }
 rustc_type_ir = { path = "../rustc_type_ir" }
 smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
-thin-vec = "0.2.8"
+thin-vec = "0.2.9"
 tracing = "0.1"
 
 [features]
diff --git a/compiler/rustc_query_system/src/cache.rs b/compiler/rustc_query_system/src/cache.rs
index d592812f79b6..7cc885be2ba6 100644
--- a/compiler/rustc_query_system/src/cache.rs
+++ b/compiler/rustc_query_system/src/cache.rs
@@ -26,7 +26,7 @@ impl<Key, Value> Cache<Key, Value> {
 }
 
 impl<Key: Eq + Hash, Value: Clone> Cache<Key, Value> {
-    pub fn get<CTX: DepContext>(&self, key: &Key, tcx: CTX) -> Option<Value> {
+    pub fn get<Tcx: DepContext>(&self, key: &Key, tcx: Tcx) -> Option<Value> {
         Some(self.hashmap.borrow().get(key)?.get(tcx))
     }
 
@@ -46,7 +46,7 @@ impl<T: Clone> WithDepNode<T> {
         WithDepNode { dep_node, cached_value }
     }
 
-    pub fn get<CTX: DepContext>(&self, tcx: CTX) -> T {
+    pub fn get<Tcx: DepContext>(&self, tcx: Tcx) -> T {
         tcx.dep_graph().read_index(self.dep_node);
         self.cached_value.clone()
     }
diff --git a/compiler/rustc_query_system/src/dep_graph/dep_node.rs b/compiler/rustc_query_system/src/dep_graph/dep_node.rs
index 5c6ce0556eb8..d79c5816a9c4 100644
--- a/compiler/rustc_query_system/src/dep_graph/dep_node.rs
+++ b/compiler/rustc_query_system/src/dep_graph/dep_node.rs
@@ -61,18 +61,18 @@ impl<K: DepKind> DepNode<K> {
     /// Creates a new, parameterless DepNode. This method will assert
     /// that the DepNode corresponding to the given DepKind actually
     /// does not require any parameters.
-    pub fn new_no_params<Ctxt>(tcx: Ctxt, kind: K) -> DepNode<K>
+    pub fn new_no_params<Tcx>(tcx: Tcx, kind: K) -> DepNode<K>
     where
-        Ctxt: super::DepContext<DepKind = K>,
+        Tcx: super::DepContext<DepKind = K>,
     {
         debug_assert_eq!(tcx.fingerprint_style(kind), FingerprintStyle::Unit);
         DepNode { kind, hash: Fingerprint::ZERO.into() }
     }
 
-    pub fn construct<Ctxt, Key>(tcx: Ctxt, kind: K, arg: &Key) -> DepNode<K>
+    pub fn construct<Tcx, Key>(tcx: Tcx, kind: K, arg: &Key) -> DepNode<K>
     where
-        Ctxt: super::DepContext<DepKind = K>,
-        Key: DepNodeParams<Ctxt>,
+        Tcx: super::DepContext<DepKind = K>,
+        Key: DepNodeParams<Tcx>,
     {
         let hash = arg.to_fingerprint(tcx);
         let dep_node = DepNode { kind, hash: hash.into() };
@@ -93,9 +93,9 @@ impl<K: DepKind> DepNode<K> {
     /// Construct a DepNode from the given DepKind and DefPathHash. This
     /// method will assert that the given DepKind actually requires a
     /// single DefId/DefPathHash parameter.
-    pub fn from_def_path_hash<Ctxt>(tcx: Ctxt, def_path_hash: DefPathHash, kind: K) -> Self
+    pub fn from_def_path_hash<Tcx>(tcx: Tcx, def_path_hash: DefPathHash, kind: K) -> Self
     where
-        Ctxt: super::DepContext<DepKind = K>,
+        Tcx: super::DepContext<DepKind = K>,
     {
         debug_assert!(tcx.fingerprint_style(kind) == FingerprintStyle::DefPathHash);
         DepNode { kind, hash: def_path_hash.0.into() }
@@ -108,18 +108,18 @@ impl<K: DepKind> fmt::Debug for DepNode<K> {
     }
 }
 
-pub trait DepNodeParams<Ctxt: DepContext>: fmt::Debug + Sized {
+pub trait DepNodeParams<Tcx: DepContext>: fmt::Debug + Sized {
     fn fingerprint_style() -> FingerprintStyle;
 
     /// This method turns the parameters of a DepNodeConstructor into an opaque
     /// Fingerprint to be used in DepNode.
     /// Not all DepNodeParams support being turned into a Fingerprint (they
     /// don't need to if the corresponding DepNode is anonymous).
-    fn to_fingerprint(&self, _: Ctxt) -> Fingerprint {
+    fn to_fingerprint(&self, _: Tcx) -> Fingerprint {
         panic!("Not implemented. Accidentally called on anonymous node?")
     }
 
-    fn to_debug_str(&self, _: Ctxt) -> String {
+    fn to_debug_str(&self, _: Tcx) -> String {
         format!("{:?}", self)
     }
 
@@ -129,10 +129,10 @@ pub trait DepNodeParams<Ctxt: DepContext>: fmt::Debug + Sized {
     /// `fingerprint_style()` is not `FingerprintStyle::Opaque`.
     /// It is always valid to return `None` here, in which case incremental
     /// compilation will treat the query as having changed instead of forcing it.
-    fn recover(tcx: Ctxt, dep_node: &DepNode<Ctxt::DepKind>) -> Option<Self>;
+    fn recover(tcx: Tcx, dep_node: &DepNode<Tcx::DepKind>) -> Option<Self>;
 }
 
-impl<Ctxt: DepContext, T> DepNodeParams<Ctxt> for T
+impl<Tcx: DepContext, T> DepNodeParams<Tcx> for T
 where
     T: for<'a> HashStable<StableHashingContext<'a>> + fmt::Debug,
 {
@@ -142,7 +142,7 @@ where
     }
 
     #[inline(always)]
-    default fn to_fingerprint(&self, tcx: Ctxt) -> Fingerprint {
+    default fn to_fingerprint(&self, tcx: Tcx) -> Fingerprint {
         tcx.with_stable_hashing_context(|mut hcx| {
             let mut hasher = StableHasher::new();
             self.hash_stable(&mut hcx, &mut hasher);
@@ -151,12 +151,12 @@ where
     }
 
     #[inline(always)]
-    default fn to_debug_str(&self, _: Ctxt) -> String {
+    default fn to_debug_str(&self, _: Tcx) -> String {
         format!("{:?}", *self)
     }
 
     #[inline(always)]
-    default fn recover(_: Ctxt, _: &DepNode<Ctxt::DepKind>) -> Option<Self> {
+    default fn recover(_: Tcx, _: &DepNode<Tcx::DepKind>) -> Option<Self> {
         None
     }
 }
@@ -166,7 +166,7 @@ where
 /// Information is retrieved by indexing the `DEP_KINDS` array using the integer value
 /// of the `DepKind`. Overall, this allows to implement `DepContext` using this manual
 /// jump table instead of large matches.
-pub struct DepKindStruct<CTX: DepContext> {
+pub struct DepKindStruct<Tcx: DepContext> {
     /// Anonymous queries cannot be replayed from one compiler invocation to the next.
     /// When their result is needed, it is recomputed. They are useful for fine-grained
     /// dependency tracking, and caching within one compiler invocation.
@@ -216,10 +216,10 @@ pub struct DepKindStruct<CTX: DepContext> {
     /// with kind `MirValidated`, we know that the GUID/fingerprint of the `DepNode`
     /// is actually a `DefPathHash`, and can therefore just look up the corresponding
     /// `DefId` in `tcx.def_path_hash_to_def_id`.
-    pub force_from_dep_node: Option<fn(tcx: CTX, dep_node: DepNode<CTX::DepKind>) -> bool>,
+    pub force_from_dep_node: Option<fn(tcx: Tcx, dep_node: DepNode<Tcx::DepKind>) -> bool>,
 
     /// Invoke a query to put the on-disk cached value in memory.
-    pub try_load_from_on_disk_cache: Option<fn(CTX, DepNode<CTX::DepKind>)>,
+    pub try_load_from_on_disk_cache: Option<fn(Tcx, DepNode<Tcx::DepKind>)>,
 }
 
 /// A "work product" corresponds to a `.o` (or other) file that we
diff --git a/compiler/rustc_query_system/src/dep_graph/graph.rs b/compiler/rustc_query_system/src/dep_graph/graph.rs
index 8ff56132749d..d86c0bebdcdf 100644
--- a/compiler/rustc_query_system/src/dep_graph/graph.rs
+++ b/compiler/rustc_query_system/src/dep_graph/graph.rs
@@ -377,9 +377,9 @@ impl<K: DepKind> DepGraph<K> {
 
     /// Executes something within an "anonymous" task, that is, a task the
     /// `DepNode` of which is determined by the list of inputs it read from.
-    pub fn with_anon_task<Ctxt: DepContext<DepKind = K>, OP, R>(
+    pub fn with_anon_task<Tcx: DepContext<DepKind = K>, OP, R>(
         &self,
-        cx: Ctxt,
+        cx: Tcx,
         dep_kind: K,
         op: OP,
     ) -> (R, DepNodeIndex)
@@ -571,12 +571,12 @@ impl<K: DepKind> DepGraph<K> {
     /// A node will have an index, when it's already been marked green, or when we can mark it
     /// green. This function will mark the current task as a reader of the specified node, when
     /// a node index can be found for that node.
-    pub fn try_mark_green<Ctxt: QueryContext<DepKind = K>>(
+    pub fn try_mark_green<Qcx: QueryContext<DepKind = K>>(
         &self,
-        tcx: Ctxt,
+        qcx: Qcx,
         dep_node: &DepNode<K>,
     ) -> Option<(SerializedDepNodeIndex, DepNodeIndex)> {
-        debug_assert!(!tcx.dep_context().is_eval_always(dep_node.kind));
+        debug_assert!(!qcx.dep_context().is_eval_always(dep_node.kind));
 
         // Return None if the dep graph is disabled
         let data = self.data.as_ref()?;
@@ -592,15 +592,16 @@ impl<K: DepKind> DepGraph<K> {
                 // in the previous compilation session too, so we can try to
                 // mark it as green by recursively marking all of its
                 // dependencies green.
-                self.try_mark_previous_green(tcx, data, prev_index, &dep_node)
+                self.try_mark_previous_green(qcx, data, prev_index, &dep_node)
                     .map(|dep_node_index| (prev_index, dep_node_index))
             }
         }
     }
 
-    fn try_mark_parent_green<Ctxt: QueryContext<DepKind = K>>(
+    #[instrument(skip(self, qcx, data, parent_dep_node_index), level = "debug")]
+    fn try_mark_parent_green<Qcx: QueryContext<DepKind = K>>(
         &self,
-        tcx: Ctxt,
+        qcx: Qcx,
         data: &DepGraphData<K>,
         parent_dep_node_index: SerializedDepNodeIndex,
         dep_node: &DepNode<K>,
@@ -613,11 +614,7 @@ impl<K: DepKind> DepGraph<K> {
                 // This dependency has been marked as green before, we are
                 // still fine and can continue with checking the other
                 // dependencies.
-                debug!(
-                    "try_mark_previous_green({:?}) --- found dependency {:?} to \
-                            be immediately green",
-                    dep_node, dep_dep_node,
-                );
+                debug!("dependency {dep_dep_node:?} was immediately green");
                 return Some(());
             }
             Some(DepNodeColor::Red) => {
@@ -625,10 +622,7 @@ impl<K: DepKind> DepGraph<K> {
                 // compared to the previous compilation session. We cannot
                 // mark the DepNode as green and also don't need to bother
                 // with checking any of the other dependencies.
-                debug!(
-                    "try_mark_previous_green({:?}) - END - dependency {:?} was immediately red",
-                    dep_node, dep_dep_node,
-                );
+                debug!("dependency {dep_dep_node:?} was immediately red");
                 return None;
             }
             None => {}
@@ -636,35 +630,26 @@ impl<K: DepKind> DepGraph<K> {
 
         // We don't know the state of this dependency. If it isn't
         // an eval_always node, let's try to mark it green recursively.
-        if !tcx.dep_context().is_eval_always(dep_dep_node.kind) {
+        if !qcx.dep_context().is_eval_always(dep_dep_node.kind) {
             debug!(
-                "try_mark_previous_green({:?}) --- state of dependency {:?} ({}) \
-                                 is unknown, trying to mark it green",
-                dep_node, dep_dep_node, dep_dep_node.hash,
+                "state of dependency {:?} ({}) is unknown, trying to mark it green",
+                dep_dep_node, dep_dep_node.hash,
             );
 
             let node_index =
-                self.try_mark_previous_green(tcx, data, parent_dep_node_index, dep_dep_node);
+                self.try_mark_previous_green(qcx, data, parent_dep_node_index, dep_dep_node);
+
             if node_index.is_some() {
-                debug!(
-                    "try_mark_previous_green({:?}) --- managed to MARK dependency {:?} as green",
-                    dep_node, dep_dep_node
-                );
+                debug!("managed to MARK dependency {dep_dep_node:?} as green",);
                 return Some(());
             }
         }
 
         // We failed to mark it green, so we try to force the query.
-        debug!(
-            "try_mark_previous_green({:?}) --- trying to force dependency {:?}",
-            dep_node, dep_dep_node
-        );
-        if !tcx.dep_context().try_force_from_dep_node(*dep_dep_node) {
+        debug!("trying to force dependency {dep_dep_node:?}");
+        if !qcx.dep_context().try_force_from_dep_node(*dep_dep_node) {
             // The DepNode could not be forced.
-            debug!(
-                "try_mark_previous_green({:?}) - END - dependency {:?} could not be forced",
-                dep_node, dep_dep_node
-            );
+            debug!("dependency {dep_dep_node:?} could not be forced");
             return None;
         }
 
@@ -672,23 +657,17 @@ impl<K: DepKind> DepGraph<K> {
 
         match dep_dep_node_color {
             Some(DepNodeColor::Green(_)) => {
-                debug!(
-                    "try_mark_previous_green({:?}) --- managed to FORCE dependency {:?} to green",
-                    dep_node, dep_dep_node
-                );
+                debug!("managed to FORCE dependency {dep_dep_node:?} to green");
                 return Some(());
             }
             Some(DepNodeColor::Red) => {
-                debug!(
-                    "try_mark_previous_green({:?}) - END - dependency {:?} was red after forcing",
-                    dep_node, dep_dep_node
-                );
+                debug!("dependency {dep_dep_node:?} was red after forcing",);
                 return None;
             }
             None => {}
         }
 
-        if !tcx.dep_context().sess().has_errors_or_delayed_span_bugs() {
+        if !qcx.dep_context().sess().has_errors_or_delayed_span_bugs() {
             panic!("try_mark_previous_green() - Forcing the DepNode should have set its color")
         }
 
@@ -702,23 +681,19 @@ impl<K: DepKind> DepGraph<K> {
         // invalid state will not be persisted to the
         // incremental compilation cache because of
         // compilation errors being present.
-        debug!(
-            "try_mark_previous_green({:?}) - END - dependency {:?} resulted in compilation error",
-            dep_node, dep_dep_node
-        );
+        debug!("dependency {dep_dep_node:?} resulted in compilation error",);
         return None;
     }
 
     /// Try to mark a dep-node which existed in the previous compilation session as green.
-    fn try_mark_previous_green<Ctxt: QueryContext<DepKind = K>>(
+    #[instrument(skip(self, qcx, data, prev_dep_node_index), level = "debug")]
+    fn try_mark_previous_green<Qcx: QueryContext<DepKind = K>>(
         &self,
-        tcx: Ctxt,
+        qcx: Qcx,
         data: &DepGraphData<K>,
         prev_dep_node_index: SerializedDepNodeIndex,
         dep_node: &DepNode<K>,
     ) -> Option<DepNodeIndex> {
-        debug!("try_mark_previous_green({:?}) - BEGIN", dep_node);
-
         #[cfg(not(parallel_compiler))]
         {
             debug_assert!(!self.dep_node_exists(dep_node));
@@ -726,14 +701,14 @@ impl<K: DepKind> DepGraph<K> {
         }
 
         // We never try to mark eval_always nodes as green
-        debug_assert!(!tcx.dep_context().is_eval_always(dep_node.kind));
+        debug_assert!(!qcx.dep_context().is_eval_always(dep_node.kind));
 
         debug_assert_eq!(data.previous.index_to_node(prev_dep_node_index), *dep_node);
 
         let prev_deps = data.previous.edge_targets_from(prev_dep_node_index);
 
         for &dep_dep_node_index in prev_deps {
-            self.try_mark_parent_green(tcx, data, dep_dep_node_index, dep_node)?
+            self.try_mark_parent_green(qcx, data, dep_dep_node_index, dep_node)?
         }
 
         // If we got here without hitting a `return` that means that all
@@ -745,7 +720,7 @@ impl<K: DepKind> DepGraph<K> {
         // We allocating an entry for the node in the current dependency graph and
         // adding all the appropriate edges imported from the previous graph
         let dep_node_index = data.current.promote_node_and_deps_to_current(
-            tcx.dep_context().profiler(),
+            qcx.dep_context().profiler(),
             &data.previous,
             prev_dep_node_index,
         );
@@ -754,7 +729,7 @@ impl<K: DepKind> DepGraph<K> {
 
         // FIXME: Store the fact that a node has diagnostics in a bit in the dep graph somewhere
         // Maybe store a list on disk and encode this fact in the DepNodeState
-        let side_effects = tcx.load_side_effects(prev_dep_node_index);
+        let side_effects = qcx.load_side_effects(prev_dep_node_index);
 
         #[cfg(not(parallel_compiler))]
         debug_assert!(
@@ -765,14 +740,14 @@ impl<K: DepKind> DepGraph<K> {
         );
 
         if !side_effects.is_empty() {
-            self.emit_side_effects(tcx, data, dep_node_index, side_effects);
+            self.emit_side_effects(qcx, data, dep_node_index, side_effects);
         }
 
         // ... and finally storing a "Green" entry in the color map.
         // Multiple threads can all write the same color here
         data.colors.insert(prev_dep_node_index, DepNodeColor::Green(dep_node_index));
 
-        debug!("try_mark_previous_green({:?}) - END - successfully marked as green", dep_node);
+        debug!("successfully marked {dep_node:?} as green");
         Some(dep_node_index)
     }
 
@@ -780,9 +755,9 @@ impl<K: DepKind> DepGraph<K> {
     /// This may be called concurrently on multiple threads for the same dep node.
     #[cold]
     #[inline(never)]
-    fn emit_side_effects<Ctxt: QueryContext<DepKind = K>>(
+    fn emit_side_effects<Qcx: QueryContext<DepKind = K>>(
         &self,
-        tcx: Ctxt,
+        qcx: Qcx,
         data: &DepGraphData<K>,
         dep_node_index: DepNodeIndex,
         side_effects: QuerySideEffects,
@@ -794,9 +769,9 @@ impl<K: DepKind> DepGraph<K> {
             // must process side effects
 
             // Promote the previous diagnostics to the current session.
-            tcx.store_side_effects(dep_node_index, side_effects.clone());
+            qcx.store_side_effects(dep_node_index, side_effects.clone());
 
-            let handle = tcx.dep_context().sess().diagnostic();
+            let handle = qcx.dep_context().sess().diagnostic();
 
             for mut diagnostic in side_effects.diagnostics {
                 handle.emit_diagnostic(&mut diagnostic);
@@ -824,7 +799,7 @@ impl<K: DepKind> DepGraph<K> {
     //
     // This method will only load queries that will end up in the disk cache.
     // Other queries will not be executed.
-    pub fn exec_cache_promotions<Ctxt: DepContext<DepKind = K>>(&self, tcx: Ctxt) {
+    pub fn exec_cache_promotions<Tcx: DepContext<DepKind = K>>(&self, tcx: Tcx) {
         let _prof_timer = tcx.profiler().generic_activity("incr_comp_query_cache_promotion");
 
         let data = self.data.as_ref().unwrap();
diff --git a/compiler/rustc_query_system/src/dep_graph/mod.rs b/compiler/rustc_query_system/src/dep_graph/mod.rs
index da2075fd5aad..e370c6990a41 100644
--- a/compiler/rustc_query_system/src/dep_graph/mod.rs
+++ b/compiler/rustc_query_system/src/dep_graph/mod.rs
@@ -52,9 +52,8 @@ pub trait DepContext: Copy {
     }
 
     /// Try to force a dep node to execute and see if it's green.
+    #[instrument(skip(self), level = "debug")]
     fn try_force_from_dep_node(self, dep_node: DepNode<Self::DepKind>) -> bool {
-        debug!("try_force_from_dep_node({:?}) --- trying to force", dep_node);
-
         let cb = self.dep_kind_info(dep_node.kind);
         if let Some(f) = cb.force_from_dep_node {
             f(self, dep_node);
diff --git a/compiler/rustc_query_system/src/ich/hcx.rs b/compiler/rustc_query_system/src/ich/hcx.rs
index 148eabb38e23..6378ec10875d 100644
--- a/compiler/rustc_query_system/src/ich/hcx.rs
+++ b/compiler/rustc_query_system/src/ich/hcx.rs
@@ -49,15 +49,13 @@ pub(super) enum BodyResolver<'tcx> {
 
 impl<'a> StableHashingContext<'a> {
     #[inline]
-    fn new_with_or_without_spans(
+    pub fn new(
         sess: &'a Session,
         definitions: &'a Definitions,
         cstore: &'a dyn CrateStore,
         source_span: &'a IndexVec<LocalDefId, Span>,
-        always_ignore_spans: bool,
     ) -> Self {
-        let hash_spans_initial =
-            !always_ignore_spans && !sess.opts.unstable_opts.incremental_ignore_spans;
+        let hash_spans_initial = !sess.opts.unstable_opts.incremental_ignore_spans;
 
         StableHashingContext {
             body_resolver: BodyResolver::Forbidden,
@@ -71,33 +69,6 @@ impl<'a> StableHashingContext<'a> {
         }
     }
 
-    #[inline]
-    pub fn new(
-        sess: &'a Session,
-        definitions: &'a Definitions,
-        cstore: &'a dyn CrateStore,
-        source_span: &'a IndexVec<LocalDefId, Span>,
-    ) -> Self {
-        Self::new_with_or_without_spans(
-            sess,
-            definitions,
-            cstore,
-            source_span,
-            /*always_ignore_spans=*/ false,
-        )
-    }
-
-    #[inline]
-    pub fn ignore_spans(
-        sess: &'a Session,
-        definitions: &'a Definitions,
-        cstore: &'a dyn CrateStore,
-        source_span: &'a IndexVec<LocalDefId, Span>,
-    ) -> Self {
-        let always_ignore_spans = true;
-        Self::new_with_or_without_spans(sess, definitions, cstore, source_span, always_ignore_spans)
-    }
-
     #[inline]
     pub fn without_hir_bodies(&mut self, f: impl FnOnce(&mut StableHashingContext<'_>)) {
         f(&mut StableHashingContext { body_resolver: BodyResolver::Ignore, ..self.clone() });
@@ -202,10 +173,4 @@ impl<'a> rustc_span::HashStableContext for StableHashingContext<'a> {
     }
 }
 
-impl<'a> rustc_data_structures::intern::InternedHashingContext for StableHashingContext<'a> {
-    fn with_def_path_and_no_spans(&mut self, f: impl FnOnce(&mut Self)) {
-        self.while_hashing_spans(false, f);
-    }
-}
-
 impl<'a> rustc_session::HashStableContext for StableHashingContext<'a> {}
diff --git a/compiler/rustc_query_system/src/query/config.rs b/compiler/rustc_query_system/src/query/config.rs
index 0a1cffa3b333..f40e174b7e79 100644
--- a/compiler/rustc_query_system/src/query/config.rs
+++ b/compiler/rustc_query_system/src/query/config.rs
@@ -11,59 +11,57 @@ use rustc_data_structures::fingerprint::Fingerprint;
 use std::fmt::Debug;
 use std::hash::Hash;
 
-pub trait QueryConfig {
+pub trait QueryConfig<Qcx: QueryContext> {
     const NAME: &'static str;
 
     type Key: Eq + Hash + Clone + Debug;
     type Value;
     type Stored: Clone;
+
+    type Cache: QueryCache<Key = Self::Key, Stored = Self::Stored, Value = Self::Value>;
+
+    // Don't use this method to access query results, instead use the methods on TyCtxt
+    fn query_state<'a>(tcx: Qcx) -> &'a QueryState<Self::Key>
+    where
+        Qcx: 'a;
+
+    // Don't use this method to access query results, instead use the methods on TyCtxt
+    fn query_cache<'a>(tcx: Qcx) -> &'a Self::Cache
+    where
+        Qcx: 'a;
+
+    // Don't use this method to compute query results, instead use the methods on TyCtxt
+    fn make_vtable(tcx: Qcx, key: &Self::Key) -> QueryVTable<Qcx, Self::Key, Self::Value>;
+
+    fn cache_on_disk(tcx: Qcx::DepContext, key: &Self::Key) -> bool;
+
+    // Don't use this method to compute query results, instead use the methods on TyCtxt
+    fn execute_query(tcx: Qcx::DepContext, k: Self::Key) -> Self::Stored;
 }
 
 #[derive(Copy, Clone)]
-pub struct QueryVTable<CTX: QueryContext, K, V> {
+pub struct QueryVTable<Qcx: QueryContext, K, V> {
     pub anon: bool,
-    pub dep_kind: CTX::DepKind,
+    pub dep_kind: Qcx::DepKind,
     pub eval_always: bool,
     pub depth_limit: bool,
 
-    pub compute: fn(CTX::DepContext, K) -> V,
+    pub compute: fn(Qcx::DepContext, K) -> V,
     pub hash_result: Option<fn(&mut StableHashingContext<'_>, &V) -> Fingerprint>,
     pub handle_cycle_error: HandleCycleError,
     // NOTE: this is also `None` if `cache_on_disk()` returns false, not just if it's unsupported by the query
-    pub try_load_from_disk: Option<fn(CTX, SerializedDepNodeIndex) -> Option<V>>,
+    pub try_load_from_disk: Option<fn(Qcx, SerializedDepNodeIndex) -> Option<V>>,
 }
 
-impl<CTX: QueryContext, K, V> QueryVTable<CTX, K, V> {
-    pub(crate) fn to_dep_node(&self, tcx: CTX::DepContext, key: &K) -> DepNode<CTX::DepKind>
+impl<Qcx: QueryContext, K, V> QueryVTable<Qcx, K, V> {
+    pub(crate) fn to_dep_node(&self, tcx: Qcx::DepContext, key: &K) -> DepNode<Qcx::DepKind>
     where
-        K: crate::dep_graph::DepNodeParams<CTX::DepContext>,
+        K: crate::dep_graph::DepNodeParams<Qcx::DepContext>,
     {
         DepNode::construct(tcx, self.dep_kind, key)
     }
 
-    pub(crate) fn compute(&self, tcx: CTX::DepContext, key: K) -> V {
+    pub(crate) fn compute(&self, tcx: Qcx::DepContext, key: K) -> V {
         (self.compute)(tcx, key)
     }
 }
-
-pub trait QueryDescription<CTX: QueryContext>: QueryConfig {
-    type Cache: QueryCache<Key = Self::Key, Stored = Self::Stored, Value = Self::Value>;
-
-    // Don't use this method to access query results, instead use the methods on TyCtxt
-    fn query_state<'a>(tcx: CTX) -> &'a QueryState<Self::Key>
-    where
-        CTX: 'a;
-
-    // Don't use this method to access query results, instead use the methods on TyCtxt
-    fn query_cache<'a>(tcx: CTX) -> &'a Self::Cache
-    where
-        CTX: 'a;
-
-    // Don't use this method to compute query results, instead use the methods on TyCtxt
-    fn make_vtable(tcx: CTX, key: &Self::Key) -> QueryVTable<CTX, Self::Key, Self::Value>;
-
-    fn cache_on_disk(tcx: CTX::DepContext, key: &Self::Key) -> bool;
-
-    // Don't use this method to compute query results, instead use the methods on TyCtxt
-    fn execute_query(tcx: CTX::DepContext, k: Self::Key) -> Self::Stored;
-}
diff --git a/compiler/rustc_query_system/src/query/job.rs b/compiler/rustc_query_system/src/query/job.rs
index ed65393f57e4..49bbcf578045 100644
--- a/compiler/rustc_query_system/src/query/job.rs
+++ b/compiler/rustc_query_system/src/query/job.rs
@@ -596,8 +596,8 @@ pub(crate) fn report_cycle<'a>(
     cycle_diag.into_diagnostic(&sess.parse_sess.span_diagnostic)
 }
 
-pub fn print_query_stack<CTX: QueryContext>(
-    tcx: CTX,
+pub fn print_query_stack<Qcx: QueryContext>(
+    qcx: Qcx,
     mut current_query: Option<QueryJobId>,
     handler: &Handler,
     num_frames: Option<usize>,
@@ -606,7 +606,7 @@ pub fn print_query_stack<CTX: QueryContext>(
     // a panic hook, which means that the global `Handler` may be in a weird
     // state if it was responsible for triggering the panic.
     let mut i = 0;
-    let query_map = tcx.try_collect_active_jobs();
+    let query_map = qcx.try_collect_active_jobs();
 
     while let Some(query) = current_query {
         if Some(i) == num_frames {
diff --git a/compiler/rustc_query_system/src/query/mod.rs b/compiler/rustc_query_system/src/query/mod.rs
index 118703fc0d48..94adef41e68f 100644
--- a/compiler/rustc_query_system/src/query/mod.rs
+++ b/compiler/rustc_query_system/src/query/mod.rs
@@ -12,7 +12,7 @@ pub use self::caches::{
 };
 
 mod config;
-pub use self::config::{QueryConfig, QueryDescription, QueryVTable};
+pub use self::config::{QueryConfig, QueryVTable};
 
 use crate::dep_graph::{DepNodeIndex, HasDepContext, SerializedDepNodeIndex};
 use rustc_data_structures::sync::Lock;
diff --git a/compiler/rustc_query_system/src/query/plumbing.rs b/compiler/rustc_query_system/src/query/plumbing.rs
index 15b89daa6db1..f8d93a27d1c2 100644
--- a/compiler/rustc_query_system/src/query/plumbing.rs
+++ b/compiler/rustc_query_system/src/query/plumbing.rs
@@ -4,7 +4,7 @@
 
 use crate::dep_graph::{DepContext, DepNode, DepNodeIndex, DepNodeParams};
 use crate::query::caches::QueryCache;
-use crate::query::config::{QueryDescription, QueryVTable};
+use crate::query::config::QueryVTable;
 use crate::query::job::{report_cycle, QueryInfo, QueryJob, QueryJobId, QueryJobInfo};
 use crate::query::{QueryContext, QueryMap, QuerySideEffects, QueryStackFrame};
 use crate::values::Value;
@@ -27,6 +27,8 @@ use std::mem;
 use std::ptr;
 use thin_vec::ThinVec;
 
+use super::QueryConfig;
+
 pub struct QueryState<K> {
     #[cfg(parallel_compiler)]
     active: Sharded<FxHashMap<K, QueryResult>>,
@@ -60,10 +62,10 @@ where
         }
     }
 
-    pub fn try_collect_active_jobs<CTX: Copy>(
+    pub fn try_collect_active_jobs<Qcx: Copy>(
         &self,
-        tcx: CTX,
-        make_query: fn(CTX, K) -> QueryStackFrame,
+        qcx: Qcx,
+        make_query: fn(Qcx, K) -> QueryStackFrame,
         jobs: &mut QueryMap,
     ) -> Option<()> {
         #[cfg(parallel_compiler)]
@@ -74,7 +76,7 @@ where
             for shard in shards.iter() {
                 for (k, v) in shard.iter() {
                     if let QueryResult::Started(ref job) = *v {
-                        let query = make_query(tcx, k.clone());
+                        let query = make_query(qcx, k.clone());
                         jobs.insert(job.id, QueryJobInfo { query, job: job.clone() });
                     }
                 }
@@ -88,7 +90,7 @@ where
             // really hurt much.)
             for (k, v) in self.active.try_lock()?.iter() {
                 if let QueryResult::Started(ref job) = *v {
-                    let query = make_query(tcx, k.clone());
+                    let query = make_query(qcx, k.clone());
                     jobs.insert(job.id, QueryJobInfo { query, job: job.clone() });
                 }
             }
@@ -117,31 +119,31 @@ where
 
 #[cold]
 #[inline(never)]
-fn mk_cycle<CTX, V, R>(
-    tcx: CTX,
+fn mk_cycle<Qcx, V, R>(
+    qcx: Qcx,
     cycle_error: CycleError,
     handler: HandleCycleError,
     cache: &dyn crate::query::QueryStorage<Value = V, Stored = R>,
 ) -> R
 where
-    CTX: QueryContext,
-    V: std::fmt::Debug + Value<CTX::DepContext>,
+    Qcx: QueryContext,
+    V: std::fmt::Debug + Value<Qcx::DepContext>,
     R: Clone,
 {
-    let error = report_cycle(tcx.dep_context().sess(), &cycle_error);
-    let value = handle_cycle_error(*tcx.dep_context(), &cycle_error, error, handler);
+    let error = report_cycle(qcx.dep_context().sess(), &cycle_error);
+    let value = handle_cycle_error(*qcx.dep_context(), &cycle_error, error, handler);
     cache.store_nocache(value)
 }
 
-fn handle_cycle_error<CTX, V>(
-    tcx: CTX,
+fn handle_cycle_error<Tcx, V>(
+    tcx: Tcx,
     cycle_error: &CycleError,
     mut error: DiagnosticBuilder<'_, ErrorGuaranteed>,
     handler: HandleCycleError,
 ) -> V
 where
-    CTX: DepContext,
-    V: Value<CTX>,
+    Tcx: DepContext,
+    V: Value<Tcx>,
 {
     use HandleCycleError::*;
     match handler {
@@ -174,14 +176,14 @@ where
     /// This function is inlined because that results in a noticeable speed-up
     /// for some compile-time benchmarks.
     #[inline(always)]
-    fn try_start<'b, CTX>(
-        tcx: &'b CTX,
+    fn try_start<'b, Qcx>(
+        qcx: &'b Qcx,
         state: &'b QueryState<K>,
         span: Span,
         key: K,
     ) -> TryGetJob<'b, K>
     where
-        CTX: QueryContext,
+        Qcx: QueryContext,
     {
         #[cfg(parallel_compiler)]
         let mut state_lock = state.active.get_shard_by_value(&key).lock();
@@ -191,8 +193,8 @@ where
 
         match lock.entry(key) {
             Entry::Vacant(entry) => {
-                let id = tcx.next_job_id();
-                let job = tcx.current_query_job();
+                let id = qcx.next_job_id();
+                let job = qcx.current_query_job();
                 let job = QueryJob::new(id, span, job);
 
                 let key = entry.key().clone();
@@ -211,8 +213,8 @@ where
                         // If we are single-threaded we know that we have cycle error,
                         // so we just return the error.
                         return TryGetJob::Cycle(id.find_cycle_in_stack(
-                            tcx.try_collect_active_jobs().unwrap(),
-                            &tcx.current_query_job(),
+                            qcx.try_collect_active_jobs().unwrap(),
+                            &qcx.current_query_job(),
                             span,
                         ));
                     }
@@ -221,7 +223,7 @@ where
                         // For parallel queries, we'll block and wait until the query running
                         // in another thread has completed. Record how long we wait in the
                         // self-profiler.
-                        let query_blocked_prof_timer = tcx.dep_context().profiler().query_blocked();
+                        let query_blocked_prof_timer = qcx.dep_context().profiler().query_blocked();
 
                         // Get the latch out
                         let latch = job.latch();
@@ -230,7 +232,7 @@ where
 
                         // With parallel queries we might just have to wait on some other
                         // thread.
-                        let result = latch.wait_on(tcx.current_query_job(), span);
+                        let result = latch.wait_on(qcx.current_query_job(), span);
 
                         match result {
                             Ok(()) => TryGetJob::JobCompleted(query_blocked_prof_timer),
@@ -333,8 +335,8 @@ where
 /// which will be used if the query is not in the cache and we need
 /// to compute it.
 #[inline]
-pub fn try_get_cached<'a, CTX, C, R, OnHit>(
-    tcx: CTX,
+pub fn try_get_cached<'a, Tcx, C, R, OnHit>(
+    tcx: Tcx,
     cache: &'a C,
     key: &C::Key,
     // `on_hit` can be called while holding a lock to the query cache
@@ -342,7 +344,7 @@ pub fn try_get_cached<'a, CTX, C, R, OnHit>(
 ) -> Result<R, ()>
 where
     C: QueryCache,
-    CTX: DepContext,
+    Tcx: DepContext,
     OnHit: FnOnce(&C::Stored) -> R,
 {
     cache.lookup(&key, |value, index| {
@@ -354,29 +356,29 @@ where
     })
 }
 
-fn try_execute_query<CTX, C>(
-    tcx: CTX,
+fn try_execute_query<Qcx, C>(
+    qcx: Qcx,
     state: &QueryState<C::Key>,
     cache: &C,
     span: Span,
     key: C::Key,
-    dep_node: Option<DepNode<CTX::DepKind>>,
-    query: &QueryVTable<CTX, C::Key, C::Value>,
+    dep_node: Option<DepNode<Qcx::DepKind>>,
+    query: &QueryVTable<Qcx, C::Key, C::Value>,
 ) -> (C::Stored, Option<DepNodeIndex>)
 where
     C: QueryCache,
-    C::Key: Clone + DepNodeParams<CTX::DepContext>,
-    C::Value: Value<CTX::DepContext>,
-    CTX: QueryContext,
+    C::Key: Clone + DepNodeParams<Qcx::DepContext>,
+    C::Value: Value<Qcx::DepContext>,
+    Qcx: QueryContext,
 {
-    match JobOwner::<'_, C::Key>::try_start(&tcx, state, span, key.clone()) {
+    match JobOwner::<'_, C::Key>::try_start(&qcx, state, span, key.clone()) {
         TryGetJob::NotYetStarted(job) => {
-            let (result, dep_node_index) = execute_job(tcx, key, dep_node, query, job.id);
+            let (result, dep_node_index) = execute_job(qcx, key, dep_node, query, job.id);
             let result = job.complete(cache, result, dep_node_index);
             (result, Some(dep_node_index))
         }
         TryGetJob::Cycle(error) => {
-            let result = mk_cycle(tcx, error, query.handle_cycle_error, cache);
+            let result = mk_cycle(qcx, error, query.handle_cycle_error, cache);
             (result, None)
         }
         #[cfg(parallel_compiler)]
@@ -385,8 +387,8 @@ where
                 .lookup(&key, |value, index| (value.clone(), index))
                 .unwrap_or_else(|_| panic!("value must be in cache after waiting"));
 
-            if std::intrinsics::unlikely(tcx.dep_context().profiler().enabled()) {
-                tcx.dep_context().profiler().query_cache_hit(index.into());
+            if std::intrinsics::unlikely(qcx.dep_context().profiler().enabled()) {
+                qcx.dep_context().profiler().query_cache_hit(index.into());
             }
             query_blocked_prof_timer.finish_with_query_invocation_id(index.into());
 
@@ -395,25 +397,25 @@ where
     }
 }
 
-fn execute_job<CTX, K, V>(
-    tcx: CTX,
+fn execute_job<Qcx, K, V>(
+    qcx: Qcx,
     key: K,
-    mut dep_node_opt: Option<DepNode<CTX::DepKind>>,
-    query: &QueryVTable<CTX, K, V>,
+    mut dep_node_opt: Option<DepNode<Qcx::DepKind>>,
+    query: &QueryVTable<Qcx, K, V>,
     job_id: QueryJobId,
 ) -> (V, DepNodeIndex)
 where
-    K: Clone + DepNodeParams<CTX::DepContext>,
+    K: Clone + DepNodeParams<Qcx::DepContext>,
     V: Debug,
-    CTX: QueryContext,
+    Qcx: QueryContext,
 {
-    let dep_graph = tcx.dep_context().dep_graph();
+    let dep_graph = qcx.dep_context().dep_graph();
 
     // Fast path for when incr. comp. is off.
     if !dep_graph.is_fully_enabled() {
-        let prof_timer = tcx.dep_context().profiler().query_provider();
-        let result = tcx.start_query(job_id, query.depth_limit, None, || {
-            query.compute(*tcx.dep_context(), key)
+        let prof_timer = qcx.dep_context().profiler().query_provider();
+        let result = qcx.start_query(job_id, query.depth_limit, None, || {
+            query.compute(*qcx.dep_context(), key)
         });
         let dep_node_index = dep_graph.next_virtual_depnode_index();
         prof_timer.finish_with_query_invocation_id(dep_node_index.into());
@@ -423,33 +425,33 @@ where
     if !query.anon && !query.eval_always {
         // `to_dep_node` is expensive for some `DepKind`s.
         let dep_node =
-            dep_node_opt.get_or_insert_with(|| query.to_dep_node(*tcx.dep_context(), &key));
+            dep_node_opt.get_or_insert_with(|| query.to_dep_node(*qcx.dep_context(), &key));
 
         // The diagnostics for this query will be promoted to the current session during
         // `try_mark_green()`, so we can ignore them here.
-        if let Some(ret) = tcx.start_query(job_id, false, None, || {
-            try_load_from_disk_and_cache_in_memory(tcx, &key, &dep_node, query)
+        if let Some(ret) = qcx.start_query(job_id, false, None, || {
+            try_load_from_disk_and_cache_in_memory(qcx, &key, &dep_node, query)
         }) {
             return ret;
         }
     }
 
-    let prof_timer = tcx.dep_context().profiler().query_provider();
+    let prof_timer = qcx.dep_context().profiler().query_provider();
     let diagnostics = Lock::new(ThinVec::new());
 
     let (result, dep_node_index) =
-        tcx.start_query(job_id, query.depth_limit, Some(&diagnostics), || {
+        qcx.start_query(job_id, query.depth_limit, Some(&diagnostics), || {
             if query.anon {
-                return dep_graph.with_anon_task(*tcx.dep_context(), query.dep_kind, || {
-                    query.compute(*tcx.dep_context(), key)
+                return dep_graph.with_anon_task(*qcx.dep_context(), query.dep_kind, || {
+                    query.compute(*qcx.dep_context(), key)
                 });
             }
 
             // `to_dep_node` is expensive for some `DepKind`s.
             let dep_node =
-                dep_node_opt.unwrap_or_else(|| query.to_dep_node(*tcx.dep_context(), &key));
+                dep_node_opt.unwrap_or_else(|| query.to_dep_node(*qcx.dep_context(), &key));
 
-            dep_graph.with_task(dep_node, *tcx.dep_context(), key, query.compute, query.hash_result)
+            dep_graph.with_task(dep_node, *qcx.dep_context(), key, query.compute, query.hash_result)
         });
 
     prof_timer.finish_with_query_invocation_id(dep_node_index.into());
@@ -459,55 +461,55 @@ where
 
     if std::intrinsics::unlikely(!side_effects.is_empty()) {
         if query.anon {
-            tcx.store_side_effects_for_anon_node(dep_node_index, side_effects);
+            qcx.store_side_effects_for_anon_node(dep_node_index, side_effects);
         } else {
-            tcx.store_side_effects(dep_node_index, side_effects);
+            qcx.store_side_effects(dep_node_index, side_effects);
         }
     }
 
     (result, dep_node_index)
 }
 
-fn try_load_from_disk_and_cache_in_memory<CTX, K, V>(
-    tcx: CTX,
+fn try_load_from_disk_and_cache_in_memory<Qcx, K, V>(
+    qcx: Qcx,
     key: &K,
-    dep_node: &DepNode<CTX::DepKind>,
-    query: &QueryVTable<CTX, K, V>,
+    dep_node: &DepNode<Qcx::DepKind>,
+    query: &QueryVTable<Qcx, K, V>,
 ) -> Option<(V, DepNodeIndex)>
 where
     K: Clone,
-    CTX: QueryContext,
+    Qcx: QueryContext,
     V: Debug,
 {
     // Note this function can be called concurrently from the same query
     // We must ensure that this is handled correctly.
 
-    let dep_graph = tcx.dep_context().dep_graph();
-    let (prev_dep_node_index, dep_node_index) = dep_graph.try_mark_green(tcx, &dep_node)?;
+    let dep_graph = qcx.dep_context().dep_graph();
+    let (prev_dep_node_index, dep_node_index) = dep_graph.try_mark_green(qcx, &dep_node)?;
 
     debug_assert!(dep_graph.is_green(dep_node));
 
     // First we try to load the result from the on-disk cache.
     // Some things are never cached on disk.
     if let Some(try_load_from_disk) = query.try_load_from_disk {
-        let prof_timer = tcx.dep_context().profiler().incr_cache_loading();
+        let prof_timer = qcx.dep_context().profiler().incr_cache_loading();
 
         // The call to `with_query_deserialization` enforces that no new `DepNodes`
         // are created during deserialization. See the docs of that method for more
         // details.
         let result =
-            dep_graph.with_query_deserialization(|| try_load_from_disk(tcx, prev_dep_node_index));
+            dep_graph.with_query_deserialization(|| try_load_from_disk(qcx, prev_dep_node_index));
 
         prof_timer.finish_with_query_invocation_id(dep_node_index.into());
 
         if let Some(result) = result {
             if std::intrinsics::unlikely(
-                tcx.dep_context().sess().opts.unstable_opts.query_dep_graph,
+                qcx.dep_context().sess().opts.unstable_opts.query_dep_graph,
             ) {
                 dep_graph.mark_debug_loaded_from_disk(*dep_node)
             }
 
-            let prev_fingerprint = tcx
+            let prev_fingerprint = qcx
                 .dep_context()
                 .dep_graph()
                 .prev_fingerprint_of(dep_node)
@@ -521,9 +523,9 @@ where
             // give us some coverage of potential bugs though.
             let try_verify = prev_fingerprint.as_value().1 % 32 == 0;
             if std::intrinsics::unlikely(
-                try_verify || tcx.dep_context().sess().opts.unstable_opts.incremental_verify_ich,
+                try_verify || qcx.dep_context().sess().opts.unstable_opts.incremental_verify_ich,
             ) {
-                incremental_verify_ich(*tcx.dep_context(), &result, dep_node, query);
+                incremental_verify_ich(*qcx.dep_context(), &result, dep_node, query);
             }
 
             return Some((result, dep_node_index));
@@ -532,7 +534,7 @@ where
         // We always expect to find a cached result for things that
         // can be forced from `DepNode`.
         debug_assert!(
-            !tcx.dep_context().fingerprint_style(dep_node.kind).reconstructible(),
+            !qcx.dep_context().fingerprint_style(dep_node.kind).reconstructible(),
             "missing on-disk cache entry for {:?}",
             dep_node
         );
@@ -540,10 +542,10 @@ where
 
     // We could not load a result from the on-disk cache, so
     // recompute.
-    let prof_timer = tcx.dep_context().profiler().query_provider();
+    let prof_timer = qcx.dep_context().profiler().query_provider();
 
     // The dep-graph for this computation is already in-place.
-    let result = dep_graph.with_ignore(|| query.compute(*tcx.dep_context(), key.clone()));
+    let result = dep_graph.with_ignore(|| query.compute(*qcx.dep_context(), key.clone()));
 
     prof_timer.finish_with_query_invocation_id(dep_node_index.into());
 
@@ -556,34 +558,38 @@ where
     //
     // See issue #82920 for an example of a miscompilation that would get turned into
     // an ICE by this check
-    incremental_verify_ich(*tcx.dep_context(), &result, dep_node, query);
+    incremental_verify_ich(*qcx.dep_context(), &result, dep_node, query);
 
     Some((result, dep_node_index))
 }
 
-fn incremental_verify_ich<CTX, K, V: Debug>(
-    tcx: CTX::DepContext,
+#[instrument(skip(qcx, result, query), level = "debug")]
+fn incremental_verify_ich<Qcx, K, V: Debug>(
+    qcx: Qcx::DepContext,
     result: &V,
-    dep_node: &DepNode<CTX::DepKind>,
-    query: &QueryVTable<CTX, K, V>,
+    dep_node: &DepNode<Qcx::DepKind>,
+    query: &QueryVTable<Qcx, K, V>,
 ) where
-    CTX: QueryContext,
+    Qcx: QueryContext,
 {
     assert!(
-        tcx.dep_graph().is_green(dep_node),
+        qcx.dep_graph().is_green(dep_node),
         "fingerprint for green query instance not loaded from cache: {:?}",
         dep_node,
     );
 
-    debug!("BEGIN verify_ich({:?})", dep_node);
     let new_hash = query.hash_result.map_or(Fingerprint::ZERO, |f| {
-        tcx.with_stable_hashing_context(|mut hcx| f(&mut hcx, result))
+        qcx.with_stable_hashing_context(|mut hcx| f(&mut hcx, result))
     });
-    let old_hash = tcx.dep_graph().prev_fingerprint_of(dep_node);
-    debug!("END verify_ich({:?})", dep_node);
+
+    let old_hash = qcx.dep_graph().prev_fingerprint_of(dep_node);
 
     if Some(new_hash) != old_hash {
-        incremental_verify_ich_cold(tcx.sess(), DebugArg::from(&dep_node), DebugArg::from(&result));
+        incremental_verify_ich_failed(
+            qcx.sess(),
+            DebugArg::from(&dep_node),
+            DebugArg::from(&result),
+        );
     }
 }
 
@@ -629,13 +635,7 @@ impl std::fmt::Debug for DebugArg<'_> {
 // different implementations for LLVM to chew on (and filling up the final
 // binary, too).
 #[cold]
-fn incremental_verify_ich_cold(sess: &Session, dep_node: DebugArg<'_>, result: DebugArg<'_>) {
-    let run_cmd = if let Some(crate_name) = &sess.opts.crate_name {
-        format!("`cargo clean -p {}` or `cargo clean`", crate_name)
-    } else {
-        "`cargo clean`".to_string()
-    };
-
+fn incremental_verify_ich_failed(sess: &Session, dep_node: DebugArg<'_>, result: DebugArg<'_>) {
     // When we emit an error message and panic, we try to debug-print the `DepNode`
     // and query result. Unfortunately, this can cause us to run additional queries,
     // which may result in another fingerprint mismatch while we're in the middle
@@ -651,6 +651,12 @@ fn incremental_verify_ich_cold(sess: &Session, dep_node: DebugArg<'_>, result: D
     if old_in_panic {
         sess.emit_err(crate::error::Reentrant);
     } else {
+        let run_cmd = if let Some(crate_name) = &sess.opts.crate_name {
+            format!("`cargo clean -p {}` or `cargo clean`", crate_name)
+        } else {
+            "`cargo clean`".to_string()
+        };
+
         sess.emit_err(crate::error::IncrementCompilation {
             run_cmd,
             dep_node: format!("{:?}", dep_node),
@@ -670,14 +676,14 @@ fn incremental_verify_ich_cold(sess: &Session, dep_node: DebugArg<'_>, result: D
 ///
 /// Note: The optimization is only available during incr. comp.
 #[inline(never)]
-fn ensure_must_run<CTX, K, V>(
-    tcx: CTX,
+fn ensure_must_run<Qcx, K, V>(
+    qcx: Qcx,
     key: &K,
-    query: &QueryVTable<CTX, K, V>,
-) -> (bool, Option<DepNode<CTX::DepKind>>)
+    query: &QueryVTable<Qcx, K, V>,
+) -> (bool, Option<DepNode<Qcx::DepKind>>)
 where
-    K: crate::dep_graph::DepNodeParams<CTX::DepContext>,
-    CTX: QueryContext,
+    K: crate::dep_graph::DepNodeParams<Qcx::DepContext>,
+    Qcx: QueryContext,
 {
     if query.eval_always {
         return (true, None);
@@ -686,10 +692,10 @@ where
     // Ensuring an anonymous query makes no sense
     assert!(!query.anon);
 
-    let dep_node = query.to_dep_node(*tcx.dep_context(), key);
+    let dep_node = query.to_dep_node(*qcx.dep_context(), key);
 
-    let dep_graph = tcx.dep_context().dep_graph();
-    match dep_graph.try_mark_green(tcx, &dep_node) {
+    let dep_graph = qcx.dep_context().dep_graph();
+    match dep_graph.try_mark_green(qcx, &dep_node) {
         None => {
             // A None return from `try_mark_green` means that this is either
             // a new dep node or that the dep node has already been marked red.
@@ -701,7 +707,7 @@ where
         }
         Some((_, dep_node_index)) => {
             dep_graph.read_index(dep_node_index);
-            tcx.dep_context().profiler().query_cache_hit(dep_node_index.into());
+            qcx.dep_context().profiler().query_cache_hit(dep_node_index.into());
             (false, None)
         }
     }
@@ -713,16 +719,16 @@ pub enum QueryMode {
     Ensure,
 }
 
-pub fn get_query<Q, CTX>(tcx: CTX, span: Span, key: Q::Key, mode: QueryMode) -> Option<Q::Stored>
+pub fn get_query<Q, Qcx>(qcx: Qcx, span: Span, key: Q::Key, mode: QueryMode) -> Option<Q::Stored>
 where
-    Q: QueryDescription<CTX>,
-    Q::Key: DepNodeParams<CTX::DepContext>,
-    Q::Value: Value<CTX::DepContext>,
-    CTX: QueryContext,
+    Q: QueryConfig<Qcx>,
+    Q::Key: DepNodeParams<Qcx::DepContext>,
+    Q::Value: Value<Qcx::DepContext>,
+    Qcx: QueryContext,
 {
-    let query = Q::make_vtable(tcx, &key);
+    let query = Q::make_vtable(qcx, &key);
     let dep_node = if let QueryMode::Ensure = mode {
-        let (must_run, dep_node) = ensure_must_run(tcx, &key, &query);
+        let (must_run, dep_node) = ensure_must_run(qcx, &key, &query);
         if !must_run {
             return None;
         }
@@ -732,33 +738,33 @@ where
     };
 
     let (result, dep_node_index) = try_execute_query(
-        tcx,
-        Q::query_state(tcx),
-        Q::query_cache(tcx),
+        qcx,
+        Q::query_state(qcx),
+        Q::query_cache(qcx),
         span,
         key,
         dep_node,
         &query,
     );
     if let Some(dep_node_index) = dep_node_index {
-        tcx.dep_context().dep_graph().read_index(dep_node_index)
+        qcx.dep_context().dep_graph().read_index(dep_node_index)
     }
     Some(result)
 }
 
-pub fn force_query<Q, CTX>(tcx: CTX, key: Q::Key, dep_node: DepNode<CTX::DepKind>)
+pub fn force_query<Q, Qcx>(qcx: Qcx, key: Q::Key, dep_node: DepNode<Qcx::DepKind>)
 where
-    Q: QueryDescription<CTX>,
-    Q::Key: DepNodeParams<CTX::DepContext>,
-    Q::Value: Value<CTX::DepContext>,
-    CTX: QueryContext,
+    Q: QueryConfig<Qcx>,
+    Q::Key: DepNodeParams<Qcx::DepContext>,
+    Q::Value: Value<Qcx::DepContext>,
+    Qcx: QueryContext,
 {
     // We may be concurrently trying both execute and force a query.
     // Ensure that only one of them runs the query.
-    let cache = Q::query_cache(tcx);
+    let cache = Q::query_cache(qcx);
     let cached = cache.lookup(&key, |_, index| {
-        if std::intrinsics::unlikely(tcx.dep_context().profiler().enabled()) {
-            tcx.dep_context().profiler().query_cache_hit(index.into());
+        if std::intrinsics::unlikely(qcx.dep_context().profiler().enabled()) {
+            qcx.dep_context().profiler().query_cache_hit(index.into());
         }
     });
 
@@ -767,9 +773,9 @@ where
         Err(()) => {}
     }
 
-    let query = Q::make_vtable(tcx, &key);
-    let state = Q::query_state(tcx);
+    let query = Q::make_vtable(qcx, &key);
+    let state = Q::query_state(qcx);
     debug_assert!(!query.anon);
 
-    try_execute_query(tcx, state, cache, DUMMY_SP, key, Some(dep_node), &query);
+    try_execute_query(qcx, state, cache, DUMMY_SP, key, Some(dep_node), &query);
 }
diff --git a/compiler/rustc_query_system/src/values.rs b/compiler/rustc_query_system/src/values.rs
index 67fbf14e6129..214656abed4d 100644
--- a/compiler/rustc_query_system/src/values.rs
+++ b/compiler/rustc_query_system/src/values.rs
@@ -1,12 +1,12 @@
 use crate::dep_graph::DepContext;
 use crate::query::QueryInfo;
 
-pub trait Value<CTX: DepContext>: Sized {
-    fn from_cycle_error(tcx: CTX, cycle: &[QueryInfo]) -> Self;
+pub trait Value<Tcx: DepContext>: Sized {
+    fn from_cycle_error(tcx: Tcx, cycle: &[QueryInfo]) -> Self;
 }
 
-impl<CTX: DepContext, T> Value<CTX> for T {
-    default fn from_cycle_error(tcx: CTX, _: &[QueryInfo]) -> T {
+impl<Tcx: DepContext, T> Value<Tcx> for T {
+    default fn from_cycle_error(tcx: Tcx, _: &[QueryInfo]) -> T {
         tcx.sess().abort_if_errors();
         // Ideally we would use `bug!` here. But bug! is only defined in rustc_middle, and it's
         // non-trivial to define it earlier.
diff --git a/compiler/rustc_resolve/src/access_levels.rs b/compiler/rustc_resolve/src/access_levels.rs
deleted file mode 100644
index 257784341e3f..000000000000
--- a/compiler/rustc_resolve/src/access_levels.rs
+++ /dev/null
@@ -1,189 +0,0 @@
-use crate::{ImportKind, NameBindingKind, Resolver};
-use rustc_ast::ast;
-use rustc_ast::visit;
-use rustc_ast::visit::Visitor;
-use rustc_ast::Crate;
-use rustc_ast::EnumDef;
-use rustc_hir::def_id::LocalDefId;
-use rustc_hir::def_id::CRATE_DEF_ID;
-use rustc_middle::middle::privacy::AccessLevel;
-use rustc_middle::ty::{DefIdTree, Visibility};
-
-pub struct AccessLevelsVisitor<'r, 'a> {
-    r: &'r mut Resolver<'a>,
-    changed: bool,
-}
-
-impl<'r, 'a> AccessLevelsVisitor<'r, 'a> {
-    /// Fills the `Resolver::access_levels` table with public & exported items
-    /// For now, this doesn't resolve macros (FIXME) and cannot resolve Impl, as we
-    /// need access to a TyCtxt for that.
-    pub fn compute_access_levels<'c>(r: &'r mut Resolver<'a>, krate: &'c Crate) {
-        let mut visitor = AccessLevelsVisitor { r, changed: false };
-
-        visitor.update(CRATE_DEF_ID, Visibility::Public, CRATE_DEF_ID, AccessLevel::Public);
-        visitor.set_bindings_access_level(CRATE_DEF_ID);
-
-        while visitor.changed {
-            visitor.reset();
-            visit::walk_crate(&mut visitor, krate);
-        }
-
-        info!("resolve::access_levels: {:#?}", r.access_levels);
-    }
-
-    fn reset(&mut self) {
-        self.changed = false;
-    }
-
-    /// Update the access level of the bindings in the given module accordingly. The module access
-    /// level has to be Exported or Public.
-    /// This will also follow `use` chains (see PrivacyVisitor::set_import_binding_access_level).
-    fn set_bindings_access_level(&mut self, module_id: LocalDefId) {
-        assert!(self.r.module_map.contains_key(&&module_id.to_def_id()));
-        let module = self.r.get_module(module_id.to_def_id()).unwrap();
-        let resolutions = self.r.resolutions(module);
-
-        for (_, name_resolution) in resolutions.borrow().iter() {
-            if let Some(mut binding) = name_resolution.borrow().binding() && !binding.is_ambiguity() {
-                // Set the given binding access level to `AccessLevel::Public` and
-                // sets the rest of the `use` chain to `AccessLevel::Exported` until
-                // we hit the actual exported item.
-
-                // FIXME: tag and is_public() condition should be removed, but assertions occur.
-                let tag = if binding.is_import() { AccessLevel::Exported } else { AccessLevel::Public };
-                if binding.vis.is_public() {
-                    let mut prev_parent_id = module_id;
-                    let mut level = AccessLevel::Public;
-                    while let NameBindingKind::Import { binding: nested_binding, import, .. } =
-                        binding.kind
-                    {
-                        let mut update = |node_id| self.update(
-                            self.r.local_def_id(node_id),
-                            binding.vis.expect_local(),
-                            prev_parent_id,
-                            level,
-                        );
-                        // In theory all the import IDs have individual visibilities and effective
-                        // visibilities, but in practice these IDs go straigth to HIR where all
-                        // their few uses assume that their (effective) visibility applies to the
-                        // whole syntactic `use` item. So we update them all to the maximum value
-                        // among the potential individual effective visibilities. Maybe HIR for
-                        // imports shouldn't use three IDs at all.
-                        update(import.id);
-                        if let ImportKind::Single { additional_ids, .. } = import.kind {
-                            update(additional_ids.0);
-                            update(additional_ids.1);
-                        }
-
-                        level = AccessLevel::Exported;
-                        prev_parent_id = self.r.local_def_id(import.id);
-                        binding = nested_binding;
-                    }
-                }
-
-                if let Some(def_id) = binding.res().opt_def_id().and_then(|id| id.as_local()) {
-                    self.update(def_id, binding.vis.expect_local(), module_id, tag);
-                }
-            }
-        }
-    }
-
-    fn update(
-        &mut self,
-        def_id: LocalDefId,
-        nominal_vis: Visibility,
-        parent_id: LocalDefId,
-        tag: AccessLevel,
-    ) {
-        let mut access_levels = std::mem::take(&mut self.r.access_levels);
-        let module_id =
-            self.r.get_nearest_non_block_module(def_id.to_def_id()).def_id().expect_local();
-        let res = access_levels.update(
-            def_id,
-            nominal_vis,
-            || Visibility::Restricted(module_id),
-            parent_id,
-            tag,
-            &*self.r,
-        );
-        if let Ok(changed) = res {
-            self.changed |= changed;
-        } else {
-            self.r.session.delay_span_bug(
-                self.r.opt_span(def_id.to_def_id()).unwrap(),
-                "Can't update effective visibility",
-            );
-        }
-        self.r.access_levels = access_levels;
-    }
-}
-
-impl<'r, 'ast> Visitor<'ast> for AccessLevelsVisitor<'ast, 'r> {
-    fn visit_item(&mut self, item: &'ast ast::Item) {
-        let def_id = self.r.local_def_id(item.id);
-        // Set access level of nested items.
-        // If it's a mod, also make the visitor walk all of its items
-        match item.kind {
-            // Resolved in rustc_privacy when types are available
-            ast::ItemKind::Impl(..) => return,
-
-            // Should be unreachable at this stage
-            ast::ItemKind::MacCall(..) => panic!(
-                "ast::ItemKind::MacCall encountered, this should not anymore appear at this stage"
-            ),
-
-            // Foreign modules inherit level from parents.
-            ast::ItemKind::ForeignMod(..) => {
-                let parent_id = self.r.local_parent(def_id);
-                self.update(def_id, Visibility::Public, parent_id, AccessLevel::Public);
-            }
-
-            // Only exported `macro_rules!` items are public, but they always are
-            ast::ItemKind::MacroDef(ref macro_def) if macro_def.macro_rules => {
-                let parent_id = self.r.local_parent(def_id);
-                let vis = self.r.visibilities[&def_id];
-                self.update(def_id, vis, parent_id, AccessLevel::Public);
-            }
-
-            ast::ItemKind::Mod(..) => {
-                self.set_bindings_access_level(def_id);
-                visit::walk_item(self, item);
-            }
-
-            ast::ItemKind::Enum(EnumDef { ref variants }, _) => {
-                self.set_bindings_access_level(def_id);
-                for variant in variants {
-                    let variant_def_id = self.r.local_def_id(variant.id);
-                    for field in variant.data.fields() {
-                        let field_def_id = self.r.local_def_id(field.id);
-                        let vis = self.r.visibilities[&field_def_id];
-                        self.update(field_def_id, vis, variant_def_id, AccessLevel::Public);
-                    }
-                }
-            }
-
-            ast::ItemKind::Struct(ref def, _) | ast::ItemKind::Union(ref def, _) => {
-                for field in def.fields() {
-                    let field_def_id = self.r.local_def_id(field.id);
-                    let vis = self.r.visibilities[&field_def_id];
-                    self.update(field_def_id, vis, def_id, AccessLevel::Public);
-                }
-            }
-
-            ast::ItemKind::Trait(..) => {
-                self.set_bindings_access_level(def_id);
-            }
-
-            ast::ItemKind::ExternCrate(..)
-            | ast::ItemKind::Use(..)
-            | ast::ItemKind::Static(..)
-            | ast::ItemKind::Const(..)
-            | ast::ItemKind::GlobalAsm(..)
-            | ast::ItemKind::TyAlias(..)
-            | ast::ItemKind::TraitAlias(..)
-            | ast::ItemKind::MacroDef(..)
-            | ast::ItemKind::Fn(..) => return,
-        }
-    }
-}
diff --git a/compiler/rustc_resolve/src/build_reduced_graph.rs b/compiler/rustc_resolve/src/build_reduced_graph.rs
index a17793ecd99b..e7e419c9b423 100644
--- a/compiler/rustc_resolve/src/build_reduced_graph.rs
+++ b/compiler/rustc_resolve/src/build_reduced_graph.rs
@@ -56,21 +56,7 @@ impl<'a, Id: Into<DefId>> ToNameBinding<'a>
 impl<'a, Id: Into<DefId>> ToNameBinding<'a> for (Res, ty::Visibility<Id>, Span, LocalExpnId) {
     fn to_name_binding(self, arenas: &'a ResolverArenas<'a>) -> &'a NameBinding<'a> {
         arenas.alloc_name_binding(NameBinding {
-            kind: NameBindingKind::Res(self.0, false),
-            ambiguity: None,
-            vis: self.1.to_def_id(),
-            span: self.2,
-            expansion: self.3,
-        })
-    }
-}
-
-struct IsMacroExport;
-
-impl<'a> ToNameBinding<'a> for (Res, ty::Visibility, Span, LocalExpnId, IsMacroExport) {
-    fn to_name_binding(self, arenas: &'a ResolverArenas<'a>) -> &'a NameBinding<'a> {
-        arenas.alloc_name_binding(NameBinding {
-            kind: NameBindingKind::Res(self.0, true),
+            kind: NameBindingKind::Res(self.0),
             ambiguity: None,
             vis: self.1.to_def_id(),
             span: self.2,
@@ -364,7 +350,6 @@ impl<'a, 'b> BuildReducedGraphVisitor<'a, 'b> {
         module_path: Vec<Segment>,
         kind: ImportKind<'a>,
         span: Span,
-        id: NodeId,
         item: &ast::Item,
         root_span: Span,
         root_id: NodeId,
@@ -377,7 +362,6 @@ impl<'a, 'b> BuildReducedGraphVisitor<'a, 'b> {
             module_path,
             imported_module: Cell::new(None),
             span,
-            id,
             use_span: item.span,
             use_span_with_attributes: item.span_with_attributes(),
             has_attributes: !item.attrs.is_empty(),
@@ -485,9 +469,11 @@ impl<'a, 'b> BuildReducedGraphVisitor<'a, 'b> {
                         }
 
                         // Replace `use foo::{ self };` with `use foo;`
+                        let self_span = source.ident.span;
                         source = module_path.pop().unwrap();
                         if rename.is_none() {
-                            ident = source.ident;
+                            // Keep the span of `self`, but the name of `foo`
+                            ident = Ident { name: source.ident.name, span: self_span };
                         }
                     }
                 } else {
@@ -574,27 +560,20 @@ impl<'a, 'b> BuildReducedGraphVisitor<'a, 'b> {
                     },
                     type_ns_only,
                     nested,
+                    id,
                     additional_ids: (id1, id2),
                 };
 
-                self.add_import(
-                    module_path,
-                    kind,
-                    use_tree.span,
-                    id,
-                    item,
-                    root_span,
-                    item.id,
-                    vis,
-                );
+                self.add_import(module_path, kind, use_tree.span, item, root_span, item.id, vis);
             }
             ast::UseTreeKind::Glob => {
                 let kind = ImportKind::Glob {
                     is_prelude: self.r.session.contains_name(&item.attrs, sym::prelude_import),
                     max_vis: Cell::new(None),
+                    id,
                 };
                 self.r.visibilities.insert(self.r.local_def_id(id), vis);
-                self.add_import(prefix, kind, use_tree.span, id, item, root_span, item.id, vis);
+                self.add_import(prefix, kind, use_tree.span, item, root_span, item.id, vis);
             }
             ast::UseTreeKind::Nested(ref items) => {
                 // Ensure there is at most one `self` in the list
@@ -881,9 +860,8 @@ impl<'a, 'b> BuildReducedGraphVisitor<'a, 'b> {
         })
         .unwrap_or((true, None, self.r.dummy_binding));
         let import = self.r.arenas.alloc_import(Import {
-            kind: ImportKind::ExternCrate { source: orig_name, target: ident },
+            kind: ImportKind::ExternCrate { source: orig_name, target: ident, id: item.id },
             root_id: item.id,
-            id: item.id,
             parent_scope: self.parent_scope,
             imported_module: Cell::new(module),
             has_attributes: !item.attrs.is_empty(),
@@ -1118,7 +1096,6 @@ impl<'a, 'b> BuildReducedGraphVisitor<'a, 'b> {
             this.r.arenas.alloc_import(Import {
                 kind: ImportKind::MacroUse,
                 root_id: item.id,
-                id: item.id,
                 parent_scope: this.parent_scope,
                 imported_module: Cell::new(Some(ModuleOrUniformRoot::Module(module))),
                 use_span_with_attributes: item.span_with_attributes(),
@@ -1278,8 +1255,22 @@ impl<'a, 'b> BuildReducedGraphVisitor<'a, 'b> {
             let binding = (res, vis, span, expansion).to_name_binding(self.r.arenas);
             self.r.set_binding_parent_module(binding, parent_scope.module);
             if is_macro_export {
-                let module = self.r.graph_root;
-                self.r.define(module, ident, MacroNS, (res, vis, span, expansion, IsMacroExport));
+                let import = self.r.arenas.alloc_import(Import {
+                    kind: ImportKind::MacroExport,
+                    root_id: item.id,
+                    parent_scope: self.parent_scope,
+                    imported_module: Cell::new(None),
+                    has_attributes: false,
+                    use_span_with_attributes: span,
+                    use_span: span,
+                    root_span: span,
+                    span: span,
+                    module_path: Vec::new(),
+                    vis: Cell::new(Some(vis)),
+                    used: Cell::new(true),
+                });
+                let import_binding = self.r.import(binding, import);
+                self.r.define(self.r.graph_root, ident, MacroNS, import_binding);
             } else {
                 self.r.check_reserved_macro_name(ident, res);
                 self.insert_unused_macro(ident, def_id, item.id, &rule_spans);
diff --git a/compiler/rustc_resolve/src/check_unused.rs b/compiler/rustc_resolve/src/check_unused.rs
index 01c3801f2232..32fb5e18276a 100644
--- a/compiler/rustc_resolve/src/check_unused.rs
+++ b/compiler/rustc_resolve/src/check_unused.rs
@@ -234,7 +234,7 @@ impl Resolver<'_> {
                         if !import.span.is_dummy() {
                             self.lint_buffer.buffer_lint(
                                 MACRO_USE_EXTERN_CRATE,
-                                import.id,
+                                import.root_id,
                                 import.span,
                                 "deprecated `#[macro_use]` attribute used to \
                                 import macros should be replaced at use sites \
@@ -244,13 +244,13 @@ impl Resolver<'_> {
                         }
                     }
                 }
-                ImportKind::ExternCrate { .. } => {
-                    let def_id = self.local_def_id(import.id);
+                ImportKind::ExternCrate { id, .. } => {
+                    let def_id = self.local_def_id(id);
                     self.maybe_unused_extern_crates.push((def_id, import.span));
                 }
                 ImportKind::MacroUse => {
                     let msg = "unused `#[macro_use]` import";
-                    self.lint_buffer.buffer_lint(UNUSED_IMPORTS, import.id, import.span, msg);
+                    self.lint_buffer.buffer_lint(UNUSED_IMPORTS, import.root_id, import.span, msg);
                 }
                 _ => {}
             }
diff --git a/compiler/rustc_resolve/src/diagnostics.rs b/compiler/rustc_resolve/src/diagnostics.rs
index 5d868ebec944..a12918b29799 100644
--- a/compiler/rustc_resolve/src/diagnostics.rs
+++ b/compiler/rustc_resolve/src/diagnostics.rs
@@ -58,16 +58,32 @@ pub(crate) enum SuggestionTarget {
 #[derive(Debug)]
 pub(crate) struct TypoSuggestion {
     pub candidate: Symbol,
+    /// The source location where the name is defined; None if the name is not defined
+    /// in source e.g. primitives
+    pub span: Option<Span>,
     pub res: Res,
     pub target: SuggestionTarget,
 }
 
 impl TypoSuggestion {
-    pub(crate) fn typo_from_res(candidate: Symbol, res: Res) -> TypoSuggestion {
-        Self { candidate, res, target: SuggestionTarget::SimilarlyNamed }
+    pub(crate) fn typo_from_ident(ident: Ident, res: Res) -> TypoSuggestion {
+        Self {
+            candidate: ident.name,
+            span: Some(ident.span),
+            res,
+            target: SuggestionTarget::SimilarlyNamed,
+        }
     }
-    pub(crate) fn single_item_from_res(candidate: Symbol, res: Res) -> TypoSuggestion {
-        Self { candidate, res, target: SuggestionTarget::SingleItem }
+    pub(crate) fn typo_from_name(candidate: Symbol, res: Res) -> TypoSuggestion {
+        Self { candidate, span: None, res, target: SuggestionTarget::SimilarlyNamed }
+    }
+    pub(crate) fn single_item_from_ident(ident: Ident, res: Res) -> TypoSuggestion {
+        Self {
+            candidate: ident.name,
+            span: Some(ident.span),
+            res,
+            target: SuggestionTarget::SingleItem,
+        }
     }
 }
 
@@ -174,12 +190,12 @@ impl<'a> Resolver<'a> {
             ModuleKind::Block => "block",
         };
 
-        let old_noun = match old_binding.is_import() {
+        let old_noun = match old_binding.is_import_user_facing() {
             true => "import",
             false => "definition",
         };
 
-        let new_participle = match new_binding.is_import() {
+        let new_participle = match new_binding.is_import_user_facing() {
             true => "imported",
             false => "defined",
         };
@@ -210,7 +226,7 @@ impl<'a> Resolver<'a> {
                 true => struct_span_err!(self.session, span, E0254, "{}", msg),
                 false => struct_span_err!(self.session, span, E0260, "{}", msg),
             },
-            _ => match (old_binding.is_import(), new_binding.is_import()) {
+            _ => match (old_binding.is_import_user_facing(), new_binding.is_import_user_facing()) {
                 (false, false) => struct_span_err!(self.session, span, E0428, "{}", msg),
                 (true, true) => struct_span_err!(self.session, span, E0252, "{}", msg),
                 _ => struct_span_err!(self.session, span, E0255, "{}", msg),
@@ -225,21 +241,27 @@ impl<'a> Resolver<'a> {
         ));
 
         err.span_label(span, format!("`{}` re{} here", name, new_participle));
-        err.span_label(
-            self.session.source_map().guess_head_span(old_binding.span),
-            format!("previous {} of the {} `{}` here", old_noun, old_kind, name),
-        );
+        if !old_binding.span.is_dummy() && old_binding.span != span {
+            err.span_label(
+                self.session.source_map().guess_head_span(old_binding.span),
+                format!("previous {} of the {} `{}` here", old_noun, old_kind, name),
+            );
+        }
 
         // See https://github.com/rust-lang/rust/issues/32354
         use NameBindingKind::Import;
+        let can_suggest = |binding: &NameBinding<'_>, import: &self::Import<'_>| {
+            !binding.span.is_dummy()
+                && !matches!(import.kind, ImportKind::MacroUse | ImportKind::MacroExport)
+        };
         let import = match (&new_binding.kind, &old_binding.kind) {
             // If there are two imports where one or both have attributes then prefer removing the
             // import without attributes.
             (Import { import: new, .. }, Import { import: old, .. })
                 if {
-                    !new_binding.span.is_dummy()
-                        && !old_binding.span.is_dummy()
-                        && (new.has_attributes || old.has_attributes)
+                    (new.has_attributes || old.has_attributes)
+                        && can_suggest(old_binding, old)
+                        && can_suggest(new_binding, new)
                 } =>
             {
                 if old.has_attributes {
@@ -249,10 +271,10 @@ impl<'a> Resolver<'a> {
                 }
             }
             // Otherwise prioritize the new binding.
-            (Import { import, .. }, other) if !new_binding.span.is_dummy() => {
+            (Import { import, .. }, other) if can_suggest(new_binding, import) => {
                 Some((import, new_binding.span, other.is_import()))
             }
-            (other, Import { import, .. }) if !old_binding.span.is_dummy() => {
+            (other, Import { import, .. }) if can_suggest(old_binding, import) => {
                 Some((import, old_binding.span, other.is_import()))
             }
             _ => None,
@@ -337,7 +359,7 @@ impl<'a> Resolver<'a> {
                     }
                 }
             }
-            ImportKind::ExternCrate { source, target } => {
+            ImportKind::ExternCrate { source, target, .. } => {
                 suggestion = Some(format!(
                     "extern crate {} as {};",
                     source.unwrap_or(target.name),
@@ -490,7 +512,7 @@ impl<'a> Resolver<'a> {
             if let Some(binding) = resolution.borrow().binding {
                 let res = binding.res();
                 if filter_fn(res) && ctxt.map_or(true, |ctxt| ctxt == key.ident.span.ctxt()) {
-                    names.push(TypoSuggestion::typo_from_res(key.ident.name, res));
+                    names.push(TypoSuggestion::typo_from_ident(key.ident, res));
                 }
             }
         }
@@ -1145,7 +1167,7 @@ impl<'a> Resolver<'a> {
                                 .get(&expn_id)
                                 .into_iter()
                                 .flatten()
-                                .map(|ident| TypoSuggestion::typo_from_res(ident.name, res)),
+                                .map(|ident| TypoSuggestion::typo_from_ident(*ident, res)),
                         );
                     }
                 }
@@ -1164,7 +1186,7 @@ impl<'a> Resolver<'a> {
                                 suggestions.extend(
                                     ext.helper_attrs
                                         .iter()
-                                        .map(|name| TypoSuggestion::typo_from_res(*name, res)),
+                                        .map(|name| TypoSuggestion::typo_from_name(*name, res)),
                                 );
                             }
                         }
@@ -1174,8 +1196,8 @@ impl<'a> Resolver<'a> {
                     if let MacroRulesScope::Binding(macro_rules_binding) = macro_rules_scope.get() {
                         let res = macro_rules_binding.binding.res();
                         if filter_fn(res) {
-                            suggestions.push(TypoSuggestion::typo_from_res(
-                                macro_rules_binding.ident.name,
+                            suggestions.push(TypoSuggestion::typo_from_ident(
+                                macro_rules_binding.ident,
                                 res,
                             ))
                         }
@@ -1186,14 +1208,14 @@ impl<'a> Resolver<'a> {
                     let root_module = this.resolve_crate_root(root_ident);
                     this.add_module_candidates(root_module, &mut suggestions, filter_fn, None);
                 }
-                Scope::Module(module, _) => {
+                Scope::Module(module) => {
                     this.add_module_candidates(module, &mut suggestions, filter_fn, None);
                 }
                 Scope::MacroUsePrelude => {
                     suggestions.extend(this.macro_use_prelude.iter().filter_map(
                         |(name, binding)| {
                             let res = binding.res();
-                            filter_fn(res).then_some(TypoSuggestion::typo_from_res(*name, res))
+                            filter_fn(res).then_some(TypoSuggestion::typo_from_name(*name, res))
                         },
                     ));
                 }
@@ -1203,14 +1225,14 @@ impl<'a> Resolver<'a> {
                         suggestions.extend(
                             BUILTIN_ATTRIBUTES
                                 .iter()
-                                .map(|attr| TypoSuggestion::typo_from_res(attr.name, res)),
+                                .map(|attr| TypoSuggestion::typo_from_name(attr.name, res)),
                         );
                     }
                 }
                 Scope::ExternPrelude => {
                     suggestions.extend(this.extern_prelude.iter().filter_map(|(ident, _)| {
                         let res = Res::Def(DefKind::Mod, CRATE_DEF_ID.to_def_id());
-                        filter_fn(res).then_some(TypoSuggestion::typo_from_res(ident.name, res))
+                        filter_fn(res).then_some(TypoSuggestion::typo_from_ident(*ident, res))
                     }));
                 }
                 Scope::ToolPrelude => {
@@ -1218,7 +1240,7 @@ impl<'a> Resolver<'a> {
                     suggestions.extend(
                         this.registered_tools
                             .iter()
-                            .map(|ident| TypoSuggestion::typo_from_res(ident.name, res)),
+                            .map(|ident| TypoSuggestion::typo_from_ident(*ident, res)),
                     );
                 }
                 Scope::StdLibPrelude => {
@@ -1235,7 +1257,8 @@ impl<'a> Resolver<'a> {
                 Scope::BuiltinTypes => {
                     suggestions.extend(PrimTy::ALL.iter().filter_map(|prim_ty| {
                         let res = Res::PrimTy(*prim_ty);
-                        filter_fn(res).then_some(TypoSuggestion::typo_from_res(prim_ty.name(), res))
+                        filter_fn(res)
+                            .then_some(TypoSuggestion::typo_from_name(prim_ty.name(), res))
                     }))
                 }
             }
@@ -1666,7 +1689,7 @@ impl<'a> Resolver<'a> {
             let a = if built_in.is_empty() { res.article() } else { "a" };
             format!("{a}{built_in} {thing}{from}", thing = res.descr())
         } else {
-            let introduced = if b.is_import() { "imported" } else { "defined" };
+            let introduced = if b.is_import_user_facing() { "imported" } else { "defined" };
             format!("the {thing} {introduced} here", thing = res.descr())
         }
     }
@@ -1725,10 +1748,10 @@ impl<'a> Resolver<'a> {
     /// If the binding refers to a tuple struct constructor with fields,
     /// returns the span of its fields.
     fn ctor_fields_span(&self, binding: &NameBinding<'_>) -> Option<Span> {
-        if let NameBindingKind::Res(
-            Res::Def(DefKind::Ctor(CtorOf::Struct, CtorKind::Fn), ctor_def_id),
-            _,
-        ) = binding.kind
+        if let NameBindingKind::Res(Res::Def(
+            DefKind::Ctor(CtorOf::Struct, CtorKind::Fn),
+            ctor_def_id,
+        )) = binding.kind
         {
             let def_id = self.parent(ctor_def_id);
             let fields = self.field_names.get(&def_id)?;
@@ -1772,7 +1795,9 @@ impl<'a> Resolver<'a> {
                         next_ident = source;
                         Some(binding)
                     }
-                    ImportKind::Glob { .. } | ImportKind::MacroUse => Some(binding),
+                    ImportKind::Glob { .. } | ImportKind::MacroUse | ImportKind::MacroExport => {
+                        Some(binding)
+                    }
                     ImportKind::ExternCrate { .. } => None,
                 },
                 _ => None,
diff --git a/compiler/rustc_resolve/src/effective_visibilities.rs b/compiler/rustc_resolve/src/effective_visibilities.rs
new file mode 100644
index 000000000000..82dcc7efb1ba
--- /dev/null
+++ b/compiler/rustc_resolve/src/effective_visibilities.rs
@@ -0,0 +1,240 @@
+use crate::{ImportKind, NameBinding, NameBindingKind, Resolver, ResolverTree};
+use rustc_ast::ast;
+use rustc_ast::visit;
+use rustc_ast::visit::Visitor;
+use rustc_ast::Crate;
+use rustc_ast::EnumDef;
+use rustc_data_structures::intern::Interned;
+use rustc_hir::def_id::LocalDefId;
+use rustc_hir::def_id::CRATE_DEF_ID;
+use rustc_middle::middle::privacy::{EffectiveVisibilities, EffectiveVisibility, Level};
+use rustc_middle::ty::Visibility;
+
+type ImportId<'a> = Interned<'a, NameBinding<'a>>;
+
+#[derive(Clone, Copy)]
+enum ParentId<'a> {
+    Def(LocalDefId),
+    Import(ImportId<'a>),
+}
+
+impl ParentId<'_> {
+    fn level(self) -> Level {
+        match self {
+            ParentId::Def(_) => Level::Direct,
+            ParentId::Import(_) => Level::Reexported,
+        }
+    }
+}
+
+pub struct EffectiveVisibilitiesVisitor<'r, 'a> {
+    r: &'r mut Resolver<'a>,
+    /// While walking import chains we need to track effective visibilities per-binding, and def id
+    /// keys in `Resolver::effective_visibilities` are not enough for that, because multiple
+    /// bindings can correspond to a single def id in imports. So we keep a separate table.
+    import_effective_visibilities: EffectiveVisibilities<ImportId<'a>>,
+    changed: bool,
+}
+
+impl<'r, 'a> EffectiveVisibilitiesVisitor<'r, 'a> {
+    /// Fills the `Resolver::effective_visibilities` table with public & exported items
+    /// For now, this doesn't resolve macros (FIXME) and cannot resolve Impl, as we
+    /// need access to a TyCtxt for that.
+    pub fn compute_effective_visibilities<'c>(r: &'r mut Resolver<'a>, krate: &'c Crate) {
+        let mut visitor = EffectiveVisibilitiesVisitor {
+            r,
+            import_effective_visibilities: Default::default(),
+            changed: false,
+        };
+
+        visitor.update(CRATE_DEF_ID, CRATE_DEF_ID);
+        visitor.set_bindings_effective_visibilities(CRATE_DEF_ID);
+
+        while visitor.changed {
+            visitor.changed = false;
+            visit::walk_crate(&mut visitor, krate);
+        }
+
+        // Update visibilities for import def ids. These are not used during the
+        // `EffectiveVisibilitiesVisitor` pass, because we have more detailed binding-based
+        // information, but are used by later passes. Effective visibility of an import def id
+        // is the maximum value among visibilities of bindings corresponding to that def id.
+        for (binding, eff_vis) in visitor.import_effective_visibilities.iter() {
+            let NameBindingKind::Import { import, .. } = binding.kind else { unreachable!() };
+            if let Some(node_id) = import.id() {
+                let mut update = |node_id| {
+                    r.effective_visibilities.update_eff_vis(
+                        r.local_def_id(node_id),
+                        eff_vis,
+                        ResolverTree(&r.definitions, &r.crate_loader),
+                    )
+                };
+                update(node_id);
+                if let ImportKind::Single { additional_ids: (id1, id2), .. } = import.kind {
+                    // In theory all the single import IDs have individual visibilities and
+                    // effective visibilities, but in practice these IDs go straight to HIR
+                    // where all their few uses assume that their (effective) visibility
+                    // applies to the whole syntactic `use` item. So they all get the same
+                    // value which is the maximum of all bindings. Maybe HIR for imports
+                    // shouldn't use three IDs at all.
+                    if id1 != ast::DUMMY_NODE_ID {
+                        update(id1);
+                    }
+                    if id2 != ast::DUMMY_NODE_ID {
+                        update(id2);
+                    }
+                }
+            }
+        }
+
+        info!("resolve::effective_visibilities: {:#?}", r.effective_visibilities);
+    }
+
+    fn nearest_normal_mod(&mut self, def_id: LocalDefId) -> LocalDefId {
+        self.r.get_nearest_non_block_module(def_id.to_def_id()).nearest_parent_mod().expect_local()
+    }
+
+    /// Update effective visibilities of bindings in the given module,
+    /// including their whole reexport chains.
+    fn set_bindings_effective_visibilities(&mut self, module_id: LocalDefId) {
+        assert!(self.r.module_map.contains_key(&&module_id.to_def_id()));
+        let module = self.r.get_module(module_id.to_def_id()).unwrap();
+        let resolutions = self.r.resolutions(module);
+
+        for (_, name_resolution) in resolutions.borrow().iter() {
+            if let Some(mut binding) = name_resolution.borrow().binding() && !binding.is_ambiguity() {
+                // Set the given effective visibility level to `Level::Direct` and
+                // sets the rest of the `use` chain to `Level::Reexported` until
+                // we hit the actual exported item.
+                let mut parent_id = ParentId::Def(module_id);
+                while let NameBindingKind::Import { binding: nested_binding, .. } = binding.kind {
+                    let binding_id = ImportId::new_unchecked(binding);
+                    self.update_import(binding_id, parent_id);
+
+                    parent_id = ParentId::Import(binding_id);
+                    binding = nested_binding;
+                }
+
+                if let Some(def_id) = binding.res().opt_def_id().and_then(|id| id.as_local()) {
+                    self.update_def(def_id, binding.vis.expect_local(), parent_id);
+                }
+            }
+        }
+    }
+
+    fn effective_vis(&self, parent_id: ParentId<'a>) -> Option<EffectiveVisibility> {
+        match parent_id {
+            ParentId::Def(def_id) => self.r.effective_visibilities.effective_vis(def_id),
+            ParentId::Import(binding) => self.import_effective_visibilities.effective_vis(binding),
+        }
+        .copied()
+    }
+
+    /// The update is guaranteed to not change the table and we can skip it.
+    fn is_noop_update(
+        &self,
+        parent_id: ParentId<'a>,
+        nominal_vis: Visibility,
+        default_vis: Visibility,
+    ) -> bool {
+        nominal_vis == default_vis
+            || match parent_id {
+                ParentId::Def(def_id) => self.r.visibilities[&def_id],
+                ParentId::Import(binding) => binding.vis.expect_local(),
+            } == default_vis
+    }
+
+    fn update_import(&mut self, binding: ImportId<'a>, parent_id: ParentId<'a>) {
+        let NameBindingKind::Import { import, .. } = binding.kind else { unreachable!() };
+        let nominal_vis = binding.vis.expect_local();
+        let default_vis = Visibility::Restricted(
+            import
+                .id()
+                .map(|id| self.nearest_normal_mod(self.r.local_def_id(id)))
+                .unwrap_or(CRATE_DEF_ID),
+        );
+        if self.is_noop_update(parent_id, nominal_vis, default_vis) {
+            return;
+        }
+        self.changed |= self.import_effective_visibilities.update(
+            binding,
+            nominal_vis,
+            default_vis,
+            self.effective_vis(parent_id),
+            parent_id.level(),
+            ResolverTree(&self.r.definitions, &self.r.crate_loader),
+        );
+    }
+
+    fn update_def(&mut self, def_id: LocalDefId, nominal_vis: Visibility, parent_id: ParentId<'a>) {
+        let default_vis = Visibility::Restricted(self.nearest_normal_mod(def_id));
+        if self.is_noop_update(parent_id, nominal_vis, default_vis) {
+            return;
+        }
+        self.changed |= self.r.effective_visibilities.update(
+            def_id,
+            nominal_vis,
+            if def_id == CRATE_DEF_ID { Visibility::Public } else { default_vis },
+            self.effective_vis(parent_id),
+            parent_id.level(),
+            ResolverTree(&self.r.definitions, &self.r.crate_loader),
+        );
+    }
+
+    fn update(&mut self, def_id: LocalDefId, parent_id: LocalDefId) {
+        self.update_def(def_id, self.r.visibilities[&def_id], ParentId::Def(parent_id));
+    }
+}
+
+impl<'r, 'ast> Visitor<'ast> for EffectiveVisibilitiesVisitor<'ast, 'r> {
+    fn visit_item(&mut self, item: &'ast ast::Item) {
+        let def_id = self.r.local_def_id(item.id);
+        // Update effective visibilities of nested items.
+        // If it's a mod, also make the visitor walk all of its items
+        match item.kind {
+            // Resolved in rustc_privacy when types are available
+            ast::ItemKind::Impl(..) => return,
+
+            // Should be unreachable at this stage
+            ast::ItemKind::MacCall(..) => panic!(
+                "ast::ItemKind::MacCall encountered, this should not anymore appear at this stage"
+            ),
+
+            ast::ItemKind::Mod(..) => {
+                self.set_bindings_effective_visibilities(def_id);
+                visit::walk_item(self, item);
+            }
+
+            ast::ItemKind::Enum(EnumDef { ref variants }, _) => {
+                self.set_bindings_effective_visibilities(def_id);
+                for variant in variants {
+                    let variant_def_id = self.r.local_def_id(variant.id);
+                    for field in variant.data.fields() {
+                        self.update(self.r.local_def_id(field.id), variant_def_id);
+                    }
+                }
+            }
+
+            ast::ItemKind::Struct(ref def, _) | ast::ItemKind::Union(ref def, _) => {
+                for field in def.fields() {
+                    self.update(self.r.local_def_id(field.id), def_id);
+                }
+            }
+
+            ast::ItemKind::Trait(..) => {
+                self.set_bindings_effective_visibilities(def_id);
+            }
+
+            ast::ItemKind::ExternCrate(..)
+            | ast::ItemKind::Use(..)
+            | ast::ItemKind::Static(..)
+            | ast::ItemKind::Const(..)
+            | ast::ItemKind::GlobalAsm(..)
+            | ast::ItemKind::TyAlias(..)
+            | ast::ItemKind::TraitAlias(..)
+            | ast::ItemKind::MacroDef(..)
+            | ast::ItemKind::ForeignMod(..)
+            | ast::ItemKind::Fn(..) => return,
+        }
+    }
+}
diff --git a/compiler/rustc_resolve/src/ident.rs b/compiler/rustc_resolve/src/ident.rs
index e0542d5479fa..0c4b35b88335 100644
--- a/compiler/rustc_resolve/src/ident.rs
+++ b/compiler/rustc_resolve/src/ident.rs
@@ -1,11 +1,9 @@
-use rustc_ast::{self as ast, NodeId};
+use rustc_ast as ast;
 use rustc_feature::is_builtin_attr_name;
 use rustc_hir::def::{DefKind, Namespace, NonMacroAttrKind, PartialRes, PerNS};
 use rustc_hir::PrimTy;
 use rustc_middle::bug;
 use rustc_middle::ty;
-use rustc_session::lint::builtin::PROC_MACRO_DERIVE_RESOLUTION_FALLBACK;
-use rustc_session::lint::BuiltinLintDiagnostics;
 use rustc_span::def_id::LocalDefId;
 use rustc_span::edition::Edition;
 use rustc_span::hygiene::{ExpnId, ExpnKind, LocalExpnId, MacroKind, SyntaxContext};
@@ -19,7 +17,7 @@ use crate::late::{
 };
 use crate::macros::{sub_namespace_match, MacroRulesScope};
 use crate::{AmbiguityError, AmbiguityErrorMisc, AmbiguityKind, Determinacy, Finalize};
-use crate::{ImportKind, LexicalScopeBinding, Module, ModuleKind, ModuleOrUniformRoot};
+use crate::{Import, ImportKind, LexicalScopeBinding, Module, ModuleKind, ModuleOrUniformRoot};
 use crate::{NameBinding, NameBindingKind, ParentScope, PathResult, PrivacyError, Res};
 use crate::{ResolutionError, Resolver, Scope, ScopeSet, Segment, ToNameBinding, Weak};
 
@@ -101,7 +99,7 @@ impl<'a> Resolver<'a> {
         };
         let mut scope = match ns {
             _ if is_absolute_path => Scope::CrateRoot,
-            TypeNS | ValueNS => Scope::Module(module, None),
+            TypeNS | ValueNS => Scope::Module(module),
             MacroNS => Scope::DeriveHelpers(parent_scope.expansion),
         };
         let mut ctxt = ctxt.normalize_to_macros_2_0();
@@ -165,7 +163,7 @@ impl<'a> Resolver<'a> {
                     MacroRulesScope::Invocation(invoc_id) => {
                         Scope::MacroRules(self.invocation_parent_scopes[&invoc_id].macro_rules)
                     }
-                    MacroRulesScope::Empty => Scope::Module(module, None),
+                    MacroRulesScope::Empty => Scope::Module(module),
                 },
                 Scope::CrateRoot => match ns {
                     TypeNS => {
@@ -174,16 +172,10 @@ impl<'a> Resolver<'a> {
                     }
                     ValueNS | MacroNS => break,
                 },
-                Scope::Module(module, prev_lint_id) => {
+                Scope::Module(module) => {
                     use_prelude = !module.no_implicit_prelude;
-                    let derive_fallback_lint_id = match scope_set {
-                        ScopeSet::Late(.., lint_id) => lint_id,
-                        _ => None,
-                    };
-                    match self.hygienic_lexical_parent(module, &mut ctxt, derive_fallback_lint_id) {
-                        Some((parent_module, lint_id)) => {
-                            Scope::Module(parent_module, lint_id.or(prev_lint_id))
-                        }
+                    match self.hygienic_lexical_parent(module, &mut ctxt) {
+                        Some(parent_module) => Scope::Module(parent_module),
                         None => {
                             ctxt.adjust(ExpnId::root());
                             match ns {
@@ -215,45 +207,13 @@ impl<'a> Resolver<'a> {
         &mut self,
         module: Module<'a>,
         ctxt: &mut SyntaxContext,
-        derive_fallback_lint_id: Option<NodeId>,
-    ) -> Option<(Module<'a>, Option<NodeId>)> {
+    ) -> Option<Module<'a>> {
         if !module.expansion.outer_expn_is_descendant_of(*ctxt) {
-            return Some((self.expn_def_scope(ctxt.remove_mark()), None));
+            return Some(self.expn_def_scope(ctxt.remove_mark()));
         }
 
         if let ModuleKind::Block = module.kind {
-            return Some((module.parent.unwrap().nearest_item_scope(), None));
-        }
-
-        // We need to support the next case under a deprecation warning
-        // ```
-        // struct MyStruct;
-        // ---- begin: this comes from a proc macro derive
-        // mod implementation_details {
-        //     // Note that `MyStruct` is not in scope here.
-        //     impl SomeTrait for MyStruct { ... }
-        // }
-        // ---- end
-        // ```
-        // So we have to fall back to the module's parent during lexical resolution in this case.
-        if derive_fallback_lint_id.is_some() {
-            if let Some(parent) = module.parent {
-                // Inner module is inside the macro, parent module is outside of the macro.
-                if module.expansion != parent.expansion
-                    && module.expansion.is_descendant_of(parent.expansion)
-                {
-                    // The macro is a proc macro derive
-                    if let Some(def_id) = module.expansion.expn_data().macro_def_id {
-                        let ext = self.get_macro_by_def_id(def_id).ext;
-                        if ext.builtin_name.is_none()
-                            && ext.macro_kind() == MacroKind::Derive
-                            && parent.expansion.outer_expn_is_descendant_of(*ctxt)
-                        {
-                            return Some((parent, derive_fallback_lint_id));
-                        }
-                    }
-                }
-            }
+            return Some(module.parent.unwrap().nearest_item_scope());
         }
 
         None
@@ -510,7 +470,7 @@ impl<'a> Resolver<'a> {
                             Err((Determinacy::Determined, _)) => Err(Determinacy::Determined),
                         }
                     }
-                    Scope::Module(module, derive_fallback_lint_id) => {
+                    Scope::Module(module) => {
                         let adjusted_parent_scope = &ParentScope { module, ..*parent_scope };
                         let binding = this.resolve_ident_in_module_unadjusted_ext(
                             ModuleOrUniformRoot::Module(module),
@@ -523,21 +483,6 @@ impl<'a> Resolver<'a> {
                         );
                         match binding {
                             Ok(binding) => {
-                                if let Some(lint_id) = derive_fallback_lint_id {
-                                    this.lint_buffer.buffer_lint_with_diagnostic(
-                                        PROC_MACRO_DERIVE_RESOLUTION_FALLBACK,
-                                        lint_id,
-                                        orig_ident.span,
-                                        &format!(
-                                            "cannot find {} `{}` in this scope",
-                                            ns.descr(),
-                                            ident
-                                        ),
-                                        BuiltinLintDiagnostics::ProcMacroDeriveResolutionFallback(
-                                            orig_ident.span,
-                                        ),
-                                    );
-                                }
                                 let misc_flags = if ptr::eq(module, this.graph_root) {
                                     Flags::MISC_SUGGEST_CRATE
                                 } else if module.is_normal() {
@@ -915,7 +860,11 @@ impl<'a> Resolver<'a> {
             }
 
             if !restricted_shadowing && binding.expansion != LocalExpnId::ROOT {
-                if let NameBindingKind::Res(_, true) = binding.kind {
+                if let NameBindingKind::Import {
+                    import: Import { kind: ImportKind::MacroExport, .. },
+                    ..
+                } = binding.kind
+                {
                     self.macro_expanded_macro_export_errors.insert((path_span, binding.span));
                 }
             }
diff --git a/compiler/rustc_resolve/src/imports.rs b/compiler/rustc_resolve/src/imports.rs
index f2cc50c199fc..4c899a5ff2d7 100644
--- a/compiler/rustc_resolve/src/imports.rs
+++ b/compiler/rustc_resolve/src/imports.rs
@@ -44,20 +44,36 @@ pub enum ImportKind<'a> {
         type_ns_only: bool,
         /// Did this import result from a nested import? ie. `use foo::{bar, baz};`
         nested: bool,
+        /// The ID of the `UseTree` that imported this `Import`.
+        ///
+        /// In the case where the `Import` was expanded from a "nested" use tree,
+        /// this id is the ID of the leaf tree. For example:
+        ///
+        /// ```ignore (pacify the merciless tidy)
+        /// use foo::bar::{a, b}
+        /// ```
+        ///
+        /// If this is the import for `foo::bar::a`, we would have the ID of the `UseTree`
+        /// for `a` in this field.
+        id: NodeId,
         /// Additional `NodeId`s allocated to a `ast::UseTree` for automatically generated `use` statement
         /// (eg. implicit struct constructors)
         additional_ids: (NodeId, NodeId),
     },
     Glob {
         is_prelude: bool,
-        max_vis: Cell<Option<ty::Visibility>>, // The visibility of the greatest re-export.
-                                               // n.b. `max_vis` is only used in `finalize_import` to check for re-export errors.
+        // The visibility of the greatest re-export.
+        // n.b. `max_vis` is only used in `finalize_import` to check for re-export errors.
+        max_vis: Cell<Option<ty::Visibility>>,
+        id: NodeId,
     },
     ExternCrate {
         source: Option<Symbol>,
         target: Ident,
+        id: NodeId,
     },
     MacroUse,
+    MacroExport,
 }
 
 /// Manually implement `Debug` for `ImportKind` because the `source/target_bindings`
@@ -71,6 +87,7 @@ impl<'a> std::fmt::Debug for ImportKind<'a> {
                 ref target,
                 ref type_ns_only,
                 ref nested,
+                ref id,
                 ref additional_ids,
                 // Ignore the following to avoid an infinite loop while printing.
                 source_bindings: _,
@@ -81,19 +98,23 @@ impl<'a> std::fmt::Debug for ImportKind<'a> {
                 .field("target", target)
                 .field("type_ns_only", type_ns_only)
                 .field("nested", nested)
+                .field("id", id)
                 .field("additional_ids", additional_ids)
                 .finish_non_exhaustive(),
-            Glob { ref is_prelude, ref max_vis } => f
+            Glob { ref is_prelude, ref max_vis, ref id } => f
                 .debug_struct("Glob")
                 .field("is_prelude", is_prelude)
                 .field("max_vis", max_vis)
+                .field("id", id)
                 .finish(),
-            ExternCrate { ref source, ref target } => f
+            ExternCrate { ref source, ref target, ref id } => f
                 .debug_struct("ExternCrate")
                 .field("source", source)
                 .field("target", target)
+                .field("id", id)
                 .finish(),
             MacroUse => f.debug_struct("MacroUse").finish(),
+            MacroExport => f.debug_struct("MacroExport").finish(),
         }
     }
 }
@@ -103,24 +124,15 @@ impl<'a> std::fmt::Debug for ImportKind<'a> {
 pub(crate) struct Import<'a> {
     pub kind: ImportKind<'a>,
 
-    /// The ID of the `extern crate`, `UseTree` etc that imported this `Import`.
-    ///
-    /// In the case where the `Import` was expanded from a "nested" use tree,
-    /// this id is the ID of the leaf tree. For example:
-    ///
-    /// ```ignore (pacify the merciless tidy)
+    /// Node ID of the "root" use item -- this is always the same as `ImportKind`'s `id`
+    /// (if it exists) except in the case of "nested" use trees, in which case
+    /// it will be the ID of the root use tree. e.g., in the example
+    /// ```ignore (incomplete code)
     /// use foo::bar::{a, b}
     /// ```
-    ///
-    /// If this is the import for `foo::bar::a`, we would have the ID of the `UseTree`
-    /// for `a` in this field.
-    pub id: NodeId,
-
-    /// The `id` of the "root" use-kind -- this is always the same as
-    /// `id` except in the case of "nested" use trees, in which case
-    /// it will be the `id` of the root use tree. e.g., in the example
-    /// from `id`, this would be the ID of the `use foo::bar`
-    /// `UseTree` node.
+    /// this would be the ID of the `use foo::bar` `UseTree` node.
+    /// In case of imports without their own node ID it's the closest node that can be used,
+    /// for example, for reporting lints.
     pub root_id: NodeId,
 
     /// Span of the entire use statement.
@@ -161,6 +173,15 @@ impl<'a> Import<'a> {
     pub(crate) fn expect_vis(&self) -> ty::Visibility {
         self.vis.get().expect("encountered cleared import visibility")
     }
+
+    pub(crate) fn id(&self) -> Option<NodeId> {
+        match self.kind {
+            ImportKind::Single { id, .. }
+            | ImportKind::Glob { id, .. }
+            | ImportKind::ExternCrate { id, .. } => Some(id),
+            ImportKind::MacroUse | ImportKind::MacroExport => None,
+        }
+    }
 }
 
 /// Records information about the resolution of a name in a namespace of a module.
@@ -368,7 +389,9 @@ impl<'a> Resolver<'a> {
             self.record_use(target, dummy_binding, false);
         } else if import.imported_module.get().is_none() {
             import.used.set(true);
-            self.used_imports.insert(import.id);
+            if let Some(id) = import.id() {
+                self.used_imports.insert(id);
+            }
         }
     }
 }
@@ -450,7 +473,7 @@ impl<'a, 'b> ImportResolver<'a, 'b> {
                 {
                     // In the case of a new import line, throw a diagnostic message
                     // for the previous line.
-                    self.throw_unresolved_import_error(errors, None);
+                    self.throw_unresolved_import_error(errors);
                     errors = vec![];
                 }
                 if seen_spans.insert(err.span) {
@@ -482,29 +505,21 @@ impl<'a, 'b> ImportResolver<'a, 'b> {
         }
 
         if !errors.is_empty() {
-            self.throw_unresolved_import_error(errors, None);
+            self.throw_unresolved_import_error(errors);
         }
     }
 
-    fn throw_unresolved_import_error(
-        &self,
-        errors: Vec<(String, UnresolvedImportError)>,
-        span: Option<MultiSpan>,
-    ) {
+    fn throw_unresolved_import_error(&self, errors: Vec<(String, UnresolvedImportError)>) {
+        if errors.is_empty() {
+            return;
+        }
+
         /// Upper limit on the number of `span_label` messages.
         const MAX_LABEL_COUNT: usize = 10;
 
-        let (span, msg) = if errors.is_empty() {
-            (span.unwrap(), "unresolved import".to_string())
-        } else {
-            let span = MultiSpan::from_spans(errors.iter().map(|(_, err)| err.span).collect());
-
-            let paths = errors.iter().map(|(path, _)| format!("`{}`", path)).collect::<Vec<_>>();
-
-            let msg = format!("unresolved import{} {}", pluralize!(paths.len()), paths.join(", "),);
-
-            (span, msg)
-        };
+        let span = MultiSpan::from_spans(errors.iter().map(|(_, err)| err.span).collect());
+        let paths = errors.iter().map(|(path, _)| format!("`{}`", path)).collect::<Vec<_>>();
+        let msg = format!("unresolved import{} {}", pluralize!(paths.len()), paths.join(", "),);
 
         let mut diag = struct_span_err!(self.r.session, span, E0432, "{}", &msg);
 
@@ -718,47 +733,51 @@ impl<'a, 'b> ImportResolver<'a, 'b> {
             PathResult::Indeterminate => unreachable!(),
         };
 
-        let (ident, target, source_bindings, target_bindings, type_ns_only) = match import.kind {
-            ImportKind::Single {
-                source,
-                target,
-                ref source_bindings,
-                ref target_bindings,
-                type_ns_only,
-                ..
-            } => (source, target, source_bindings, target_bindings, type_ns_only),
-            ImportKind::Glob { is_prelude, ref max_vis } => {
-                if import.module_path.len() <= 1 {
-                    // HACK(eddyb) `lint_if_path_starts_with_module` needs at least
-                    // 2 segments, so the `resolve_path` above won't trigger it.
-                    let mut full_path = import.module_path.clone();
-                    full_path.push(Segment::from_ident(Ident::empty()));
-                    self.r.lint_if_path_starts_with_module(Some(finalize), &full_path, None);
-                }
-
-                if let ModuleOrUniformRoot::Module(module) = module {
-                    if ptr::eq(module, import.parent_scope.module) {
-                        // Importing a module into itself is not allowed.
-                        return Some(UnresolvedImportError {
-                            span: import.span,
-                            label: Some(String::from("cannot glob-import a module into itself")),
-                            note: None,
-                            suggestion: None,
-                            candidate: None,
-                        });
+        let (ident, target, source_bindings, target_bindings, type_ns_only, import_id) =
+            match import.kind {
+                ImportKind::Single {
+                    source,
+                    target,
+                    ref source_bindings,
+                    ref target_bindings,
+                    type_ns_only,
+                    id,
+                    ..
+                } => (source, target, source_bindings, target_bindings, type_ns_only, id),
+                ImportKind::Glob { is_prelude, ref max_vis, id } => {
+                    if import.module_path.len() <= 1 {
+                        // HACK(eddyb) `lint_if_path_starts_with_module` needs at least
+                        // 2 segments, so the `resolve_path` above won't trigger it.
+                        let mut full_path = import.module_path.clone();
+                        full_path.push(Segment::from_ident(Ident::empty()));
+                        self.r.lint_if_path_starts_with_module(Some(finalize), &full_path, None);
                     }
-                }
-                if !is_prelude
+
+                    if let ModuleOrUniformRoot::Module(module) = module {
+                        if ptr::eq(module, import.parent_scope.module) {
+                            // Importing a module into itself is not allowed.
+                            return Some(UnresolvedImportError {
+                                span: import.span,
+                                label: Some(String::from(
+                                    "cannot glob-import a module into itself",
+                                )),
+                                note: None,
+                                suggestion: None,
+                                candidate: None,
+                            });
+                        }
+                    }
+                    if !is_prelude
                     && let Some(max_vis) = max_vis.get()
                     && !max_vis.is_at_least(import.expect_vis(), &*self.r)
                 {
                     let msg = "glob import doesn't reexport anything because no candidate is public enough";
-                    self.r.lint_buffer.buffer_lint(UNUSED_IMPORTS, import.id, import.span, msg);
+                    self.r.lint_buffer.buffer_lint(UNUSED_IMPORTS, id, import.span, msg);
                 }
-                return None;
-            }
-            _ => unreachable!(),
-        };
+                    return None;
+                }
+                _ => unreachable!(),
+            };
 
         let mut all_ns_err = true;
         self.r.per_ns(|this, ns| {
@@ -858,7 +877,7 @@ impl<'a, 'b> ImportResolver<'a, 'b> {
                                         match binding.kind {
                                             // Never suggest the name that has binding error
                                             // i.e., the name that cannot be previously resolved
-                                            NameBindingKind::Res(Res::Err, _) => None,
+                                            NameBindingKind::Res(Res::Err) => None,
                                             _ => Some(i.name),
                                         }
                                     }
@@ -960,7 +979,7 @@ impl<'a, 'b> ImportResolver<'a, 'b> {
                 );
                 self.r.lint_buffer.buffer_lint(
                     PUB_USE_OF_PRIVATE_EXTERN_CRATE,
-                    import.id,
+                    import_id,
                     import.span,
                     &msg,
                 );
@@ -989,7 +1008,7 @@ impl<'a, 'b> ImportResolver<'a, 'b> {
                     let mut err =
                         struct_span_err!(self.r.session, import.span, E0364, "{error_msg}");
                     match binding.kind {
-                        NameBindingKind::Res(Res::Def(DefKind::Macro(_), def_id), _)
+                        NameBindingKind::Res(Res::Def(DefKind::Macro(_), def_id))
                             // exclude decl_macro
                             if self.r.get_macro_by_def_id(def_id).macro_rules =>
                         {
@@ -1029,7 +1048,7 @@ impl<'a, 'b> ImportResolver<'a, 'b> {
         // purposes it's good enough to just favor one over the other.
         self.r.per_ns(|this, ns| {
             if let Ok(binding) = source_bindings[ns].get() {
-                this.import_res_map.entry(import.id).or_default()[ns] = Some(binding.res());
+                this.import_res_map.entry(import_id).or_default()[ns] = Some(binding.res());
             }
         });
 
@@ -1047,6 +1066,9 @@ impl<'a, 'b> ImportResolver<'a, 'b> {
         target_bindings: &PerNS<Cell<Option<&'b NameBinding<'b>>>>,
         target: Ident,
     ) {
+        // This function is only called for single imports.
+        let ImportKind::Single { id, .. } = import.kind else { unreachable!() };
+
         // Skip if the import was produced by a macro.
         if import.parent_scope.expansion != LocalExpnId::ROOT {
             return;
@@ -1094,7 +1116,7 @@ impl<'a, 'b> ImportResolver<'a, 'b> {
             redundant_spans.dedup();
             self.r.lint_buffer.buffer_lint_with_diagnostic(
                 UNUSED_IMPORTS,
-                import.id,
+                id,
                 import.span,
                 &format!("the item `{}` is imported redundantly", ident),
                 BuiltinLintDiagnostics::RedundantImport(redundant_spans, ident),
@@ -1103,6 +1125,9 @@ impl<'a, 'b> ImportResolver<'a, 'b> {
     }
 
     fn resolve_glob_import(&mut self, import: &'b Import<'b>) {
+        // This function is only called for glob imports.
+        let ImportKind::Glob { id, is_prelude, .. } = import.kind else { unreachable!() };
+
         let ModuleOrUniformRoot::Module(module) = import.imported_module.get().unwrap() else {
             self.r.session.span_err(import.span, "cannot glob-import all possible crates");
             return;
@@ -1113,7 +1138,7 @@ impl<'a, 'b> ImportResolver<'a, 'b> {
             return;
         } else if ptr::eq(module, import.parent_scope.module) {
             return;
-        } else if let ImportKind::Glob { is_prelude: true, .. } = import.kind {
+        } else if is_prelude {
             self.r.prelude = Some(module);
             return;
         }
@@ -1145,7 +1170,7 @@ impl<'a, 'b> ImportResolver<'a, 'b> {
         }
 
         // Record the destination of this import
-        self.r.record_partial_res(import.id, PartialRes::new(module.res().unwrap()));
+        self.r.record_partial_res(id, PartialRes::new(module.res().unwrap()));
     }
 
     // Miscellaneous post-processing, including recording re-exports,
@@ -1204,5 +1229,6 @@ fn import_kind_to_string(import_kind: &ImportKind<'_>) -> String {
         ImportKind::Glob { .. } => "*".to_string(),
         ImportKind::ExternCrate { .. } => "<extern crate>".to_string(),
         ImportKind::MacroUse => "#[macro_use]".to_string(),
+        ImportKind::MacroExport => "#[macro_export]".to_string(),
     }
 }
diff --git a/compiler/rustc_resolve/src/late.rs b/compiler/rustc_resolve/src/late.rs
index 58853346a928..ede67813883d 100644
--- a/compiler/rustc_resolve/src/late.rs
+++ b/compiler/rustc_resolve/src/late.rs
@@ -30,8 +30,9 @@ use rustc_span::{BytePos, Span};
 use smallvec::{smallvec, SmallVec};
 
 use rustc_span::source_map::{respan, Spanned};
+use std::assert_matches::debug_assert_matches;
 use std::collections::{hash_map::Entry, BTreeSet};
-use std::mem::{replace, take};
+use std::mem::{replace, swap, take};
 
 mod diagnostics;
 
@@ -526,6 +527,7 @@ struct DiagnosticMetadata<'ast> {
 
     /// Used to detect possible new binding written without `let` and to provide structured suggestion.
     in_assignment: Option<&'ast Expr>,
+    is_assign_rhs: bool,
 
     /// If we are currently in a trait object definition. Used to point at the bounds when
     /// encountering a struct or enum.
@@ -568,7 +570,7 @@ struct LateResolutionVisitor<'a, 'b, 'ast> {
     /// They will be used to determine the correct lifetime for the fn return type.
     /// The `LifetimeElisionCandidate` is used for diagnostics, to suggest introducing named
     /// lifetimes.
-    lifetime_elision_candidates: Option<FxIndexMap<LifetimeRes, LifetimeElisionCandidate>>,
+    lifetime_elision_candidates: Option<Vec<(LifetimeRes, LifetimeElisionCandidate)>>,
 
     /// The trait that the current context can refer to.
     current_trait_ref: Option<(Module<'a>, TraitRef)>,
@@ -1802,7 +1804,7 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
         match res {
             LifetimeRes::Param { .. } | LifetimeRes::Fresh { .. } | LifetimeRes::Static => {
                 if let Some(ref mut candidates) = self.lifetime_elision_candidates {
-                    candidates.insert(res, candidate);
+                    candidates.push((res, candidate));
                 }
             }
             LifetimeRes::Infer | LifetimeRes::Error | LifetimeRes::ElidedAnchor { .. } => {}
@@ -1855,12 +1857,25 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
         has_self: bool,
         inputs: impl Iterator<Item = (Option<&'ast Pat>, &'ast Ty)>,
     ) -> Result<LifetimeRes, (Vec<MissingLifetime>, Vec<ElisionFnParameter>)> {
-        let outer_candidates =
-            replace(&mut self.lifetime_elision_candidates, Some(Default::default()));
+        enum Elision {
+            /// We have not found any candidate.
+            None,
+            /// We have a candidate bound to `self`.
+            Self_(LifetimeRes),
+            /// We have a candidate bound to a parameter.
+            Param(LifetimeRes),
+            /// We failed elision.
+            Err,
+        }
 
-        let mut elision_lifetime = None;
-        let mut lifetime_count = 0;
+        // Save elision state to reinstate it later.
+        let outer_candidates = self.lifetime_elision_candidates.take();
+
+        // Result of elision.
+        let mut elision_lifetime = Elision::None;
+        // Information for diagnostics.
         let mut parameter_info = Vec::new();
+        let mut all_candidates = Vec::new();
 
         let mut bindings = smallvec![(PatBoundCtx::Product, Default::default())];
         for (index, (pat, ty)) in inputs.enumerate() {
@@ -1870,12 +1885,17 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
                     this.resolve_pattern(pat, PatternSource::FnParam, &mut bindings);
                 }
             });
-            self.visit_ty(ty);
 
-            if let Some(ref candidates) = self.lifetime_elision_candidates {
-                let new_count = candidates.len();
-                let local_count = new_count - lifetime_count;
-                if local_count != 0 {
+            // Record elision candidates only for this parameter.
+            debug_assert_matches!(self.lifetime_elision_candidates, None);
+            self.lifetime_elision_candidates = Some(Default::default());
+            self.visit_ty(ty);
+            let local_candidates = self.lifetime_elision_candidates.take();
+
+            if let Some(candidates) = local_candidates {
+                let distinct: FxHashSet<_> = candidates.iter().map(|(res, _)| *res).collect();
+                let lifetime_count = distinct.len();
+                if lifetime_count != 0 {
                     parameter_info.push(ElisionFnParameter {
                         index,
                         ident: if let Some(pat) = pat && let PatKind::Ident(_, ident, _) = pat.kind {
@@ -1883,48 +1903,64 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
                         } else {
                             None
                         },
-                        lifetime_count: local_count,
+                        lifetime_count,
                         span: ty.span,
                     });
+                    all_candidates.extend(candidates.into_iter().filter_map(|(_, candidate)| {
+                        match candidate {
+                            LifetimeElisionCandidate::Ignore | LifetimeElisionCandidate::Named => {
+                                None
+                            }
+                            LifetimeElisionCandidate::Missing(missing) => Some(missing),
+                        }
+                    }));
+                }
+                let mut distinct_iter = distinct.into_iter();
+                if let Some(res) = distinct_iter.next() {
+                    match elision_lifetime {
+                        // We are the first parameter to bind lifetimes.
+                        Elision::None => {
+                            if distinct_iter.next().is_none() {
+                                // We have a single lifetime => success.
+                                elision_lifetime = Elision::Param(res)
+                            } else {
+                                // We have have multiple lifetimes => error.
+                                elision_lifetime = Elision::Err;
+                            }
+                        }
+                        // We have 2 parameters that bind lifetimes => error.
+                        Elision::Param(_) => elision_lifetime = Elision::Err,
+                        // `self` elision takes precedence over everything else.
+                        Elision::Self_(_) | Elision::Err => {}
+                    }
                 }
-                lifetime_count = new_count;
             }
 
             // Handle `self` specially.
             if index == 0 && has_self {
                 let self_lifetime = self.find_lifetime_for_self(ty);
                 if let Set1::One(lifetime) = self_lifetime {
-                    elision_lifetime = Some(lifetime);
-                    self.lifetime_elision_candidates = None;
+                    // We found `self` elision.
+                    elision_lifetime = Elision::Self_(lifetime);
                 } else {
-                    self.lifetime_elision_candidates = Some(Default::default());
-                    lifetime_count = 0;
+                    // We do not have `self` elision: disregard the `Elision::Param` that we may
+                    // have found.
+                    elision_lifetime = Elision::None;
                 }
             }
             debug!("(resolving function / closure) recorded parameter");
         }
 
-        let all_candidates = replace(&mut self.lifetime_elision_candidates, outer_candidates);
-        debug!(?all_candidates);
+        // Reinstate elision state.
+        debug_assert_matches!(self.lifetime_elision_candidates, None);
+        self.lifetime_elision_candidates = outer_candidates;
 
-        if let Some(res) = elision_lifetime {
+        if let Elision::Param(res) | Elision::Self_(res) = elision_lifetime {
             return Ok(res);
         }
 
-        // We do not have a `self` candidate, look at the full list.
-        let all_candidates = all_candidates.unwrap();
-        if all_candidates.len() == 1 {
-            Ok(*all_candidates.first().unwrap().0)
-        } else {
-            let all_candidates = all_candidates
-                .into_iter()
-                .filter_map(|(_, candidate)| match candidate {
-                    LifetimeElisionCandidate::Ignore | LifetimeElisionCandidate::Named => None,
-                    LifetimeElisionCandidate::Missing(missing) => Some(missing),
-                })
-                .collect();
-            Err((all_candidates, parameter_info))
-        }
+        // We do not have a candidate.
+        Err((all_candidates, parameter_info))
     }
 
     /// List all the lifetimes that appear in the provided type.
@@ -2394,7 +2430,7 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
         // Do not account for the parameters we just bound for function lifetime elision.
         if let Some(ref mut candidates) = self.lifetime_elision_candidates {
             for (_, res) in function_lifetime_rib.bindings.values() {
-                candidates.remove(res);
+                candidates.retain(|(r, _)| r != res);
             }
         }
 
@@ -3334,11 +3370,6 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
             let (mut err, candidates) =
                 this.smart_resolve_report_errors(path, path_span, PathSource::Type, None);
 
-            if candidates.is_empty() {
-                err.cancel();
-                return Some(parent_err);
-            }
-
             // There are two different error messages user might receive at
             // this point:
             // - E0412 cannot find type `{}` in this scope
@@ -3348,37 +3379,62 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
             // latter one - for paths in expression-position.
             //
             // Thus (since we're in expression-position at this point), not to
-            // confuse the user, we want to keep the *message* from E0432 (so
+            // confuse the user, we want to keep the *message* from E0433 (so
             // `parent_err`), but we want *hints* from E0412 (so `err`).
             //
             // And that's what happens below - we're just mixing both messages
             // into a single one.
             let mut parent_err = this.r.into_struct_error(parent_err.span, parent_err.node);
 
+            // overwrite all properties with the parent's error message
             err.message = take(&mut parent_err.message);
             err.code = take(&mut parent_err.code);
+            swap(&mut err.span, &mut parent_err.span);
             err.children = take(&mut parent_err.children);
+            err.sort_span = parent_err.sort_span;
+            err.is_lint = parent_err.is_lint;
+
+            // merge the parent's suggestions with the typo suggestions
+            fn append_result<T, E>(res1: &mut Result<Vec<T>, E>, res2: Result<Vec<T>, E>) {
+                match res1 {
+                    Ok(vec1) => match res2 {
+                        Ok(mut vec2) => vec1.append(&mut vec2),
+                        Err(e) => *res1 = Err(e),
+                    },
+                    Err(_) => (),
+                };
+            }
+            append_result(&mut err.suggestions, parent_err.suggestions.clone());
 
             parent_err.cancel();
 
             let def_id = this.parent_scope.module.nearest_parent_mod();
 
             if this.should_report_errs() {
-                this.r.use_injections.push(UseError {
-                    err,
-                    candidates,
-                    def_id,
-                    instead: false,
-                    suggestion: None,
-                    path: path.into(),
-                    is_call: source.is_call(),
-                });
+                if candidates.is_empty() {
+                    // When there is no suggested imports, we can just emit the error
+                    // and suggestions immediately. Note that we bypass the usually error
+                    // reporting routine (ie via `self.r.report_error`) because we need
+                    // to post-process the `ResolutionError` above.
+                    err.emit();
+                } else {
+                    // If there are suggested imports, the error reporting is delayed
+                    this.r.use_injections.push(UseError {
+                        err,
+                        candidates,
+                        def_id,
+                        instead: false,
+                        suggestion: None,
+                        path: path.into(),
+                        is_call: source.is_call(),
+                    });
+                }
             } else {
                 err.cancel();
             }
 
             // We don't return `Some(parent_err)` here, because the error will
-            // be already printed as part of the `use` injections
+            // be already printed either immediately or as part of the `use` injections
             None
         };
 
@@ -3908,10 +3964,15 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
                 self.resolve_expr(elem, Some(expr));
                 self.visit_expr(idx);
             }
-            ExprKind::Assign(..) => {
-                let old = self.diagnostic_metadata.in_assignment.replace(expr);
-                visit::walk_expr(self, expr);
-                self.diagnostic_metadata.in_assignment = old;
+            ExprKind::Assign(ref lhs, ref rhs, _) => {
+                if !self.diagnostic_metadata.is_assign_rhs {
+                    self.diagnostic_metadata.in_assignment = Some(expr);
+                }
+                self.visit_expr(lhs);
+                self.diagnostic_metadata.is_assign_rhs = true;
+                self.diagnostic_metadata.in_assignment = None;
+                self.visit_expr(rhs);
+                self.diagnostic_metadata.is_assign_rhs = false;
             }
             _ => {
                 visit::walk_expr(self, expr);
diff --git a/compiler/rustc_resolve/src/late/diagnostics.rs b/compiler/rustc_resolve/src/late/diagnostics.rs
index 23c5fac8b71c..95eff92ef5e2 100644
--- a/compiler/rustc_resolve/src/late/diagnostics.rs
+++ b/compiler/rustc_resolve/src/late/diagnostics.rs
@@ -38,8 +38,8 @@ type Res = def::Res<ast::NodeId>;
 /// A field or associated item from self type suggested in case of resolution failure.
 enum AssocSuggestion {
     Field,
-    MethodWithSelf,
-    AssocFn,
+    MethodWithSelf { called: bool },
+    AssocFn { called: bool },
     AssocType,
     AssocConst,
 }
@@ -48,8 +48,14 @@ impl AssocSuggestion {
     fn action(&self) -> &'static str {
         match self {
             AssocSuggestion::Field => "use the available field",
-            AssocSuggestion::MethodWithSelf => "call the method with the fully-qualified path",
-            AssocSuggestion::AssocFn => "call the associated function",
+            AssocSuggestion::MethodWithSelf { called: true } => {
+                "call the method with the fully-qualified path"
+            }
+            AssocSuggestion::MethodWithSelf { called: false } => {
+                "refer to the method with the fully-qualified path"
+            }
+            AssocSuggestion::AssocFn { called: true } => "call the associated function",
+            AssocSuggestion::AssocFn { called: false } => "refer to the associated function",
             AssocSuggestion::AssocConst => "use the associated `const`",
             AssocSuggestion::AssocType => "use the associated type",
         }
@@ -144,7 +150,7 @@ struct BaseError {
 #[derive(Debug)]
 enum TypoCandidate {
     Typo(TypoSuggestion),
-    Shadowed(Res),
+    Shadowed(Res, Option<Span>),
     None,
 }
 
@@ -152,7 +158,7 @@ impl TypoCandidate {
     fn to_opt_suggestion(self) -> Option<TypoSuggestion> {
         match self {
             TypoCandidate::Typo(sugg) => Some(sugg),
-            TypoCandidate::Shadowed(_) | TypoCandidate::None => None,
+            TypoCandidate::Shadowed(_, _) | TypoCandidate::None => None,
         }
     }
 }
@@ -213,26 +219,26 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
             let (mod_prefix, mod_str, suggestion) = if path.len() == 1 {
                 debug!(?self.diagnostic_metadata.current_impl_items);
                 debug!(?self.diagnostic_metadata.current_function);
-                let suggestion = if let Some(items) = self.diagnostic_metadata.current_impl_items
+                let suggestion = if self.current_trait_ref.is_none()
                     && let Some((fn_kind, _)) = self.diagnostic_metadata.current_function
-                    && self.current_trait_ref.is_none()
                     && let Some(FnCtxt::Assoc(_)) = fn_kind.ctxt()
+                    && let Some(items) = self.diagnostic_metadata.current_impl_items
                     && let Some(item) = items.iter().find(|i| {
-                        if let AssocItemKind::Fn(fn_) = &i.kind
-                            && !fn_.sig.decl.has_self()
-                            && i.ident.name == item_str.name
+                        if let AssocItemKind::Fn(_) = &i.kind && i.ident.name == item_str.name
                         {
                             debug!(?item_str.name);
-                            debug!(?fn_.sig.decl.inputs);
                             return true
                         }
                         false
                     })
+                    && let AssocItemKind::Fn(fn_) = &item.kind
                 {
+                    debug!(?fn_);
+                    let self_sugg = if fn_.sig.decl.has_self() { "self." } else { "Self::" };
                     Some((
-                        item_span,
+                        item_span.shrink_to_lo(),
                         "consider using the associated function",
-                        format!("Self::{}", item.ident)
+                        self_sugg.to_string()
                     ))
                 } else {
                     None
@@ -316,7 +322,12 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
         }
 
         self.suggest_bare_struct_literal(&mut err);
-        self.suggest_pattern_match_with_let(&mut err, source, span);
+
+        if self.suggest_pattern_match_with_let(&mut err, source, span) {
+            // Fallback label.
+            err.span_label(base_error.span, &base_error.fallback_label);
+            return (err, Vec::new());
+        }
 
         self.suggest_self_or_self_ref(&mut err, path, span);
         self.detect_assoct_type_constraint_meant_as_path(&mut err, &base_error);
@@ -335,7 +346,11 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
         if !self.type_ascription_suggestion(&mut err, base_error.span) {
             let mut fallback =
                 self.suggest_trait_and_bounds(&mut err, source, res, span, &base_error);
+
+            // if we have suggested using pattern matching, then don't add needless suggestions
+            // for typos.
             fallback |= self.suggest_typo(&mut err, source, path, span, &base_error);
+
             if fallback {
                 // Fallback label.
                 err.span_label(base_error.span, &base_error.fallback_label);
@@ -381,11 +396,13 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
     }
 
     fn suggest_self_or_self_ref(&mut self, err: &mut Diagnostic, path: &[Segment], span: Span) {
-        let is_assoc_fn = self.self_type_is_available();
+        if !self.self_type_is_available() {
+            return;
+        }
         let Some(path_last_segment) = path.last() else { return };
         let item_str = path_last_segment.ident;
         // Emit help message for fake-self from other languages (e.g., `this` in Javascript).
-        if ["this", "my"].contains(&item_str.as_str()) && is_assoc_fn {
+        if ["this", "my"].contains(&item_str.as_str()) {
             err.span_suggestion_short(
                 span,
                 "you might have meant to use `self` here instead",
@@ -422,7 +439,7 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
 
     fn try_lookup_name_relaxed(
         &mut self,
-        err: &mut DiagnosticBuilder<'_, ErrorGuaranteed>,
+        err: &mut Diagnostic,
         source: PathSource<'_>,
         path: &[Segment],
         span: Span,
@@ -436,7 +453,6 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
         let is_enum_variant = &|res| matches!(res, Res::Def(DefKind::Variant, _));
         let path_str = Segment::names_to_string(path);
         let ident_span = path.last().map_or(span, |ident| ident.ident.span);
-
         let mut candidates = self
             .r
             .lookup_import_candidates(ident, ns, &self.parent_scope, is_expected)
@@ -482,7 +498,7 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
                         .contains(span)
                     {
                         // Already reported this issue on the lhs of the type ascription.
-                        err.delay_as_bug();
+                        err.downgrade_to_delayed_bug();
                         return (true, candidates);
                     }
                 }
@@ -516,7 +532,9 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
         let typo_sugg =
             self.lookup_typo_candidate(path, source.namespace(), is_expected).to_opt_suggestion();
         if path.len() == 1 && self.self_type_is_available() {
-            if let Some(candidate) = self.lookup_assoc_candidate(ident, ns, is_expected) {
+            if let Some(candidate) =
+                self.lookup_assoc_candidate(ident, ns, is_expected, source.is_call())
+            {
                 let self_is_available = self.self_value_is_available(path[0].ident.span);
                 match candidate {
                     AssocSuggestion::Field => {
@@ -531,16 +549,21 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
                             err.span_label(span, "a field by this name exists in `Self`");
                         }
                     }
-                    AssocSuggestion::MethodWithSelf if self_is_available => {
+                    AssocSuggestion::MethodWithSelf { called } if self_is_available => {
+                        let msg = if called {
+                            "you might have meant to call the method"
+                        } else {
+                            "you might have meant to refer to the method"
+                        };
                         err.span_suggestion(
                             span,
-                            "you might have meant to call the method",
+                            msg,
                             format!("self.{path_str}"),
                             Applicability::MachineApplicable,
                         );
                     }
-                    AssocSuggestion::MethodWithSelf
-                    | AssocSuggestion::AssocFn
+                    AssocSuggestion::MethodWithSelf { .. }
+                    | AssocSuggestion::AssocFn { .. }
                     | AssocSuggestion::AssocConst
                     | AssocSuggestion::AssocType => {
                         err.span_suggestion(
@@ -594,7 +617,7 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
 
     fn suggest_trait_and_bounds(
         &mut self,
-        err: &mut DiagnosticBuilder<'_, ErrorGuaranteed>,
+        err: &mut Diagnostic,
         source: PathSource<'_>,
         res: Option<Res>,
         span: Span,
@@ -669,7 +692,7 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
 
     fn suggest_typo(
         &mut self,
-        err: &mut DiagnosticBuilder<'_, ErrorGuaranteed>,
+        err: &mut Diagnostic,
         source: PathSource<'_>,
         path: &[Segment],
         span: Span,
@@ -678,9 +701,20 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
         let is_expected = &|res| source.is_expected(res);
         let ident_span = path.last().map_or(span, |ident| ident.ident.span);
         let typo_sugg = self.lookup_typo_candidate(path, source.namespace(), is_expected);
-        if let TypoCandidate::Shadowed(res) = typo_sugg
-            && let Some(id) = res.opt_def_id()
-            && let Some(sugg_span) = self.r.opt_span(id)
+        let is_in_same_file = &|sp1, sp2| {
+            let source_map = self.r.session.source_map();
+            let file1 = source_map.span_to_filename(sp1);
+            let file2 = source_map.span_to_filename(sp2);
+            file1 == file2
+        };
+        // print 'you might have meant' if the candidate is (1) is a shadowed name with
+        // accessible definition and (2) either defined in the same crate as the typo
+        // (could be in a different file) or introduced in the same file as the typo
+        // (could belong to a different crate)
+        if let TypoCandidate::Shadowed(res, Some(sugg_span)) = typo_sugg
+            && res
+                .opt_def_id()
+                .map_or(false, |id| id.is_local() || is_in_same_file(span, sugg_span))
         {
             err.span_label(
                 sugg_span,
@@ -717,7 +751,7 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
 
     fn err_code_special_cases(
         &mut self,
-        err: &mut DiagnosticBuilder<'_, ErrorGuaranteed>,
+        err: &mut Diagnostic,
         source: PathSource<'_>,
         path: &[Segment],
         span: Span,
@@ -771,19 +805,18 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
             return false;
         }
         err.code(rustc_errors::error_code!(E0411));
-        err.span_label(
-            span,
-            "`Self` is only available in impls, traits, and type definitions".to_string(),
-        );
+        err.span_label(span, "`Self` is only available in impls, traits, and type definitions");
         if let Some(item_kind) = self.diagnostic_metadata.current_item {
-            err.span_label(
-                item_kind.ident.span,
-                format!(
-                    "`Self` not allowed in {} {}",
-                    item_kind.kind.article(),
-                    item_kind.kind.descr()
-                ),
-            );
+            if !item_kind.ident.span.is_dummy() {
+                err.span_label(
+                    item_kind.ident.span,
+                    format!(
+                        "`Self` not allowed in {} {}",
+                        item_kind.kind.article(),
+                        item_kind.kind.descr()
+                    ),
+                );
+            }
         }
         true
     }
@@ -916,7 +949,7 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
         err: &mut Diagnostic,
         source: PathSource<'_>,
         span: Span,
-    ) {
+    ) -> bool {
         if let PathSource::Expr(_) = source &&
         let Some(Expr {
                     span: expr_span,
@@ -933,8 +966,10 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
                     "let ",
                     Applicability::MaybeIncorrect,
                 );
+                return true;
             }
         }
+        false
     }
 
     fn get_single_associated_item(
@@ -960,10 +995,7 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
                         .collect();
                 if targets.len() == 1 {
                     let target = targets[0];
-                    return Some(TypoSuggestion::single_item_from_res(
-                        target.0.ident.name,
-                        target.1,
-                    ));
+                    return Some(TypoSuggestion::single_item_from_ident(target.0.ident, target.1));
                 }
             }
         }
@@ -1498,6 +1530,7 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
         ident: Ident,
         ns: Namespace,
         filter_fn: FilterFn,
+        called: bool,
     ) -> Option<AssocSuggestion>
     where
         FilterFn: Fn(Res) -> bool,
@@ -1512,7 +1545,6 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
                 _ => None,
             }
         }
-
         // Fields are generally expected in the same contexts as locals.
         if filter_fn(Res::Local(ast::DUMMY_NODE_ID)) {
             if let Some(node_id) =
@@ -1539,9 +1571,9 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
                     return Some(match &assoc_item.kind {
                         ast::AssocItemKind::Const(..) => AssocSuggestion::AssocConst,
                         ast::AssocItemKind::Fn(box ast::Fn { sig, .. }) if sig.decl.has_self() => {
-                            AssocSuggestion::MethodWithSelf
+                            AssocSuggestion::MethodWithSelf { called }
                         }
-                        ast::AssocItemKind::Fn(..) => AssocSuggestion::AssocFn,
+                        ast::AssocItemKind::Fn(..) => AssocSuggestion::AssocFn { called },
                         ast::AssocItemKind::Type(..) => AssocSuggestion::AssocType,
                         ast::AssocItemKind::MacCall(_) => continue,
                     });
@@ -1560,10 +1592,12 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
                 let res = binding.res();
                 if filter_fn(res) {
                     if self.r.has_self.contains(&res.def_id()) {
-                        return Some(AssocSuggestion::MethodWithSelf);
+                        return Some(AssocSuggestion::MethodWithSelf { called });
                     } else {
                         match res {
-                            Res::Def(DefKind::AssocFn, _) => return Some(AssocSuggestion::AssocFn),
+                            Res::Def(DefKind::AssocFn, _) => {
+                                return Some(AssocSuggestion::AssocFn { called });
+                            }
                             Res::Def(DefKind::AssocConst, _) => {
                                 return Some(AssocSuggestion::AssocConst);
                             }
@@ -1602,7 +1636,7 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
                 // Locals and type parameters
                 for (ident, &res) in &rib.bindings {
                     if filter_fn(res) && ident.span.ctxt() == rib_ctxt {
-                        names.push(TypoSuggestion::typo_from_res(ident.name, res));
+                        names.push(TypoSuggestion::typo_from_ident(*ident, res));
                     }
                 }
 
@@ -1631,9 +1665,7 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
                                             Res::Def(DefKind::Mod, crate_id.as_def_id());
 
                                         if filter_fn(crate_mod) {
-                                            Some(TypoSuggestion::typo_from_res(
-                                                ident.name, crate_mod,
-                                            ))
+                                            Some(TypoSuggestion::typo_from_ident(*ident, crate_mod))
                                         } else {
                                             None
                                         }
@@ -1652,7 +1684,7 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
             // Add primitive types to the mix
             if filter_fn(Res::PrimTy(PrimTy::Bool)) {
                 names.extend(PrimTy::ALL.iter().map(|prim_ty| {
-                    TypoSuggestion::typo_from_res(prim_ty.name(), Res::PrimTy(*prim_ty))
+                    TypoSuggestion::typo_from_name(prim_ty.name(), Res::PrimTy(*prim_ty))
                 }))
             }
         } else {
@@ -1679,7 +1711,7 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
                     return TypoCandidate::None;
                 };
                 if found == name {
-                    TypoCandidate::Shadowed(sugg.res)
+                    TypoCandidate::Shadowed(sugg.res, sugg.span)
                 } else {
                     TypoCandidate::Typo(sugg)
                 }
@@ -1780,29 +1812,22 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
         false
     }
 
-    fn let_binding_suggestion(&self, err: &mut Diagnostic, ident_span: Span) -> bool {
-        // try to give a suggestion for this pattern: `name = 1`, which is common in other languages
-        let mut added_suggestion = false;
-        if let Some(Expr { kind: ExprKind::Assign(lhs, _rhs, _), .. }) = self.diagnostic_metadata.in_assignment &&
+    // try to give a suggestion for this pattern: `name = blah`, which is common in other languages
+    // suggest `let name = blah` to introduce a new binding
+    fn let_binding_suggestion(&mut self, err: &mut Diagnostic, ident_span: Span) -> bool {
+        if let Some(Expr { kind: ExprKind::Assign(lhs, .. ), .. }) = self.diagnostic_metadata.in_assignment &&
             let ast::ExprKind::Path(None, _) = lhs.kind {
-                let sm = self.r.session.source_map();
-                let line_span = sm.span_extend_to_line(ident_span);
-                let ident_name = sm.span_to_snippet(ident_span).unwrap();
-                // HACK(chenyukang): make sure ident_name is at the starting of the line to protect against macros
-                if sm
-                    .span_to_snippet(line_span)
-                    .map_or(false, |s| s.trim().starts_with(&ident_name))
-                {
+                if !ident_span.from_expansion() {
                     err.span_suggestion_verbose(
                         ident_span.shrink_to_lo(),
                         "you might have meant to introduce a new binding",
                         "let ".to_string(),
                         Applicability::MaybeIncorrect,
                     );
-                    added_suggestion = true;
+                    return true;
                 }
             }
-        added_suggestion
+        false
     }
 
     fn find_module(&mut self, def_id: DefId) -> Option<(Module<'a>, ImportSuggestion)> {
@@ -1911,7 +1936,7 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
                 err.span_suggestions(
                     span,
                     &msg,
-                    suggestable_variants.into_iter(),
+                    suggestable_variants,
                     Applicability::MaybeIncorrect,
                 );
             }
@@ -1965,7 +1990,7 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
                 err.span_suggestions(
                     span,
                     msg,
-                    suggestable_variants.into_iter(),
+                    suggestable_variants,
                     Applicability::MaybeIncorrect,
                 );
             }
@@ -1995,7 +2020,7 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
                 err.span_suggestions(
                     span,
                     msg,
-                    suggestable_variants_with_placeholders.into_iter(),
+                    suggestable_variants_with_placeholders,
                     Applicability::HasPlaceholders,
                 );
             }
diff --git a/compiler/rustc_resolve/src/lib.rs b/compiler/rustc_resolve/src/lib.rs
index 1c1976af5054..9ca3588fff45 100644
--- a/compiler/rustc_resolve/src/lib.rs
+++ b/compiler/rustc_resolve/src/lib.rs
@@ -7,6 +7,7 @@
 //! Type-relative name resolution (methods, fields, associated items) happens in `rustc_hir_analysis`.
 
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
+#![feature(assert_matches)]
 #![feature(box_patterns)]
 #![feature(drain_filter)]
 #![feature(if_let_guard)]
@@ -40,11 +41,12 @@ use rustc_hir::TraitCandidate;
 use rustc_index::vec::IndexVec;
 use rustc_metadata::creader::{CStore, CrateLoader};
 use rustc_middle::metadata::ModChild;
-use rustc_middle::middle::privacy::AccessLevels;
+use rustc_middle::middle::privacy::EffectiveVisibilities;
 use rustc_middle::span_bug;
-use rustc_middle::ty::{self, DefIdTree, MainDefinition, RegisteredTools, ResolverOutputs};
+use rustc_middle::ty::{self, DefIdTree, MainDefinition, RegisteredTools};
+use rustc_middle::ty::{ResolverGlobalCtxt, ResolverOutputs};
 use rustc_query_system::ich::StableHashingContext;
-use rustc_session::cstore::{CrateStore, CrateStoreDyn, MetadataLoaderDyn};
+use rustc_session::cstore::{CrateStore, MetadataLoaderDyn};
 use rustc_session::lint::LintBuffer;
 use rustc_session::Session;
 use rustc_span::hygiene::{ExpnId, LocalExpnId, MacroKind, SyntaxContext, Transparency};
@@ -62,15 +64,15 @@ use imports::{Import, ImportKind, ImportResolver, NameResolution};
 use late::{HasGenericParams, PathSource, PatternSource};
 use macros::{MacroRulesBinding, MacroRulesScope, MacroRulesScopeRef};
 
-use crate::access_levels::AccessLevelsVisitor;
+use crate::effective_visibilities::EffectiveVisibilitiesVisitor;
 
 type Res = def::Res<NodeId>;
 
-mod access_levels;
 mod build_reduced_graph;
 mod check_unused;
 mod def_collector;
 mod diagnostics;
+mod effective_visibilities;
 mod ident;
 mod imports;
 mod late;
@@ -102,9 +104,7 @@ enum Scope<'a> {
     DeriveHelpersCompat,
     MacroRules(MacroRulesScopeRef<'a>),
     CrateRoot,
-    // The node ID is for reporting the `PROC_MACRO_DERIVE_RESOLUTION_FALLBACK`
-    // lint if it should be reported.
-    Module(Module<'a>, Option<NodeId>),
+    Module(Module<'a>),
     MacroUsePrelude,
     BuiltinAttrs,
     ExternPrelude,
@@ -644,7 +644,7 @@ impl<'a> ToNameBinding<'a> for &'a NameBinding<'a> {
 
 #[derive(Clone, Debug)]
 enum NameBindingKind<'a> {
-    Res(Res, /* is_macro_export */ bool),
+    Res(Res),
     Module(Module<'a>),
     Import { binding: &'a NameBinding<'a>, import: &'a Import<'a>, used: Cell<bool> },
 }
@@ -743,7 +743,7 @@ impl<'a> NameBinding<'a> {
 
     fn res(&self) -> Res {
         match self.kind {
-            NameBindingKind::Res(res, _) => res,
+            NameBindingKind::Res(res) => res,
             NameBindingKind::Module(module) => module.res().unwrap(),
             NameBindingKind::Import { binding, .. } => binding.res(),
         }
@@ -760,10 +760,10 @@ impl<'a> NameBinding<'a> {
     fn is_possibly_imported_variant(&self) -> bool {
         match self.kind {
             NameBindingKind::Import { binding, .. } => binding.is_possibly_imported_variant(),
-            NameBindingKind::Res(
-                Res::Def(DefKind::Variant | DefKind::Ctor(CtorOf::Variant, ..), _),
+            NameBindingKind::Res(Res::Def(
+                DefKind::Variant | DefKind::Ctor(CtorOf::Variant, ..),
                 _,
-            ) => true,
+            )) => true,
             NameBindingKind::Res(..) | NameBindingKind::Module(..) => false,
         }
     }
@@ -786,6 +786,13 @@ impl<'a> NameBinding<'a> {
         matches!(self.kind, NameBindingKind::Import { .. })
     }
 
+    /// The binding introduced by `#[macro_export] macro_rules` is a public import, but it might
+    /// not be perceived as such by users, so treat it as a non-import in some diagnostics.
+    fn is_import_user_facing(&self) -> bool {
+        matches!(self.kind, NameBindingKind::Import { import, .. }
+            if !matches!(import.kind, ImportKind::MacroExport))
+    }
+
     fn is_glob_import(&self) -> bool {
         match self.kind {
             NameBindingKind::Import { import, .. } => import.is_glob(),
@@ -1029,7 +1036,7 @@ pub struct Resolver<'a> {
     proc_macros: Vec<NodeId>,
     confused_type_with_std_module: FxHashMap<Span, Span>,
 
-    access_levels: AccessLevels,
+    effective_visibilities: EffectiveVisibilities,
 }
 
 /// Nothing really interesting here; it just provides memory for the rest of the crate.
@@ -1099,14 +1106,27 @@ impl<'a> AsMut<Resolver<'a>> for Resolver<'a> {
     }
 }
 
+/// A minimal subset of resolver that can implemenent `DefIdTree`, sometimes
+/// required to satisfy borrow checker by avoiding borrowing the whole resolver.
+#[derive(Clone, Copy)]
+struct ResolverTree<'a, 'b>(&'a Definitions, &'a CrateLoader<'b>);
+
+impl DefIdTree for ResolverTree<'_, '_> {
+    #[inline]
+    fn opt_parent(self, id: DefId) -> Option<DefId> {
+        let ResolverTree(definitions, crate_loader) = self;
+        match id.as_local() {
+            Some(id) => definitions.def_key(id).parent,
+            None => crate_loader.cstore().def_key(id).parent,
+        }
+        .map(|index| DefId { index, ..id })
+    }
+}
+
 impl<'a, 'b> DefIdTree for &'a Resolver<'b> {
     #[inline]
     fn opt_parent(self, id: DefId) -> Option<DefId> {
-        match id.as_local() {
-            Some(id) => self.definitions.def_key(id).parent,
-            None => self.cstore().def_key(id).parent,
-        }
-        .map(|index| DefId { index, ..id })
+        ResolverTree(&self.definitions, &self.crate_loader).opt_parent(id)
     }
 }
 
@@ -1281,7 +1301,7 @@ impl<'a> Resolver<'a> {
 
             arenas,
             dummy_binding: arenas.alloc_name_binding(NameBinding {
-                kind: NameBindingKind::Res(Res::Err, false),
+                kind: NameBindingKind::Res(Res::Err),
                 ambiguity: None,
                 expansion: LocalExpnId::ROOT,
                 span: DUMMY_SP,
@@ -1333,7 +1353,7 @@ impl<'a> Resolver<'a> {
             trait_impls: Default::default(),
             proc_macros: Default::default(),
             confused_type_with_std_module: Default::default(),
-            access_levels: Default::default(),
+            effective_visibilities: Default::default(),
         };
 
         let root_parent_scope = ParentScope::module(graph_root, &resolver);
@@ -1376,9 +1396,7 @@ impl<'a> Resolver<'a> {
         Default::default()
     }
 
-    pub fn into_outputs(
-        self,
-    ) -> (Definitions, Box<CrateStoreDyn>, ResolverOutputs, ty::ResolverAstLowering) {
+    pub fn into_outputs(self) -> ResolverOutputs {
         let proc_macros = self.proc_macros.iter().map(|id| self.local_def_id(*id)).collect();
         let definitions = self.definitions;
         let cstore = Box::new(self.crate_loader.into_cstore());
@@ -1393,13 +1411,14 @@ impl<'a> Resolver<'a> {
         let glob_map = self.glob_map;
         let main_def = self.main_def;
         let confused_type_with_std_module = self.confused_type_with_std_module;
-        let access_levels = self.access_levels;
-        let resolutions = ResolverOutputs {
+        let effective_visibilities = self.effective_visibilities;
+        let global_ctxt = ResolverGlobalCtxt {
+            cstore,
             source_span,
             expn_that_defined,
             visibilities,
             has_pub_restricted,
-            access_levels,
+            effective_visibilities,
             extern_crate_map,
             reexport_map,
             glob_map,
@@ -1416,7 +1435,7 @@ impl<'a> Resolver<'a> {
             confused_type_with_std_module,
             registered_tools: self.registered_tools,
         };
-        let resolutions_lowering = ty::ResolverAstLowering {
+        let ast_lowering = ty::ResolverAstLowering {
             legacy_const_generic_args: self.legacy_const_generic_args,
             partial_res_map: self.partial_res_map,
             import_res_map: self.import_res_map,
@@ -1429,16 +1448,15 @@ impl<'a> Resolver<'a> {
             trait_map: self.trait_map,
             builtin_macro_kinds: self.builtin_macro_kinds,
         };
-        (definitions, cstore, resolutions, resolutions_lowering)
+        ResolverOutputs { definitions, global_ctxt, ast_lowering }
     }
 
-    pub fn clone_outputs(
-        &self,
-    ) -> (Definitions, Box<CrateStoreDyn>, ResolverOutputs, ty::ResolverAstLowering) {
+    pub fn clone_outputs(&self) -> ResolverOutputs {
         let proc_macros = self.proc_macros.iter().map(|id| self.local_def_id(*id)).collect();
         let definitions = self.definitions.clone();
         let cstore = Box::new(self.cstore().clone());
-        let resolutions = ResolverOutputs {
+        let global_ctxt = ResolverGlobalCtxt {
+            cstore,
             source_span: self.source_span.clone(),
             expn_that_defined: self.expn_that_defined.clone(),
             visibilities: self.visibilities.clone(),
@@ -1458,9 +1476,9 @@ impl<'a> Resolver<'a> {
             proc_macros,
             confused_type_with_std_module: self.confused_type_with_std_module.clone(),
             registered_tools: self.registered_tools.clone(),
-            access_levels: self.access_levels.clone(),
+            effective_visibilities: self.effective_visibilities.clone(),
         };
-        let resolutions_lowering = ty::ResolverAstLowering {
+        let ast_lowering = ty::ResolverAstLowering {
             legacy_const_generic_args: self.legacy_const_generic_args.clone(),
             partial_res_map: self.partial_res_map.clone(),
             import_res_map: self.import_res_map.clone(),
@@ -1473,7 +1491,7 @@ impl<'a> Resolver<'a> {
             trait_map: self.trait_map.clone(),
             builtin_macro_kinds: self.builtin_macro_kinds.clone(),
         };
-        (definitions, cstore, resolutions, resolutions_lowering)
+        ResolverOutputs { definitions, global_ctxt, ast_lowering }
     }
 
     fn create_stable_hashing_context(&self) -> StableHashingContext<'_> {
@@ -1521,8 +1539,8 @@ impl<'a> Resolver<'a> {
     pub fn resolve_crate(&mut self, krate: &Crate) {
         self.session.time("resolve_crate", || {
             self.session.time("finalize_imports", || ImportResolver { r: self }.finalize_imports());
-            self.session.time("resolve_access_levels", || {
-                AccessLevelsVisitor::compute_access_levels(self, krate)
+            self.session.time("compute_effective_visibilities", || {
+                EffectiveVisibilitiesVisitor::compute_effective_visibilities(self, krate)
             });
             self.session.time("finalize_macro_resolutions", || self.finalize_macro_resolutions());
             self.session.time("late_resolve_crate", || self.late_resolve_crate(krate));
@@ -1551,7 +1569,7 @@ impl<'a> Resolver<'a> {
 
         self.visit_scopes(ScopeSet::All(TypeNS, false), parent_scope, ctxt, |this, scope, _, _| {
             match scope {
-                Scope::Module(module, _) => {
+                Scope::Module(module) => {
                     this.traits_in_module(module, assoc_item, &mut found_traits);
                 }
                 Scope::StdLibPrelude => {
@@ -1613,10 +1631,12 @@ impl<'a> Resolver<'a> {
     ) -> SmallVec<[LocalDefId; 1]> {
         let mut import_ids = smallvec![];
         while let NameBindingKind::Import { import, binding, .. } = kind {
-            let id = self.local_def_id(import.id);
-            self.maybe_unused_trait_imports.insert(id);
+            if let Some(node_id) = import.id() {
+                let def_id = self.local_def_id(node_id);
+                self.maybe_unused_trait_imports.insert(def_id);
+                import_ids.push(def_id);
+            }
             self.add_to_glob_map(&import, trait_name);
-            import_ids.push(id);
             kind = &binding.kind;
         }
         import_ids
@@ -1683,7 +1703,9 @@ impl<'a> Resolver<'a> {
             }
             used.set(true);
             import.used.set(true);
-            self.used_imports.insert(import.id);
+            if let Some(id) = import.id() {
+                self.used_imports.insert(id);
+            }
             self.add_to_glob_map(&import, ident);
             self.record_use(ident, binding, false);
         }
@@ -1691,8 +1713,8 @@ impl<'a> Resolver<'a> {
 
     #[inline]
     fn add_to_glob_map(&mut self, import: &Import<'_>, ident: Ident) {
-        if import.is_glob() {
-            let def_id = self.local_def_id(import.id);
+        if let ImportKind::Glob { id, .. } = import.kind {
+            let def_id = self.local_def_id(id);
             self.glob_map.entry(def_id).or_default().insert(ident.name);
         }
     }
@@ -1910,6 +1932,11 @@ impl<'a> Resolver<'a> {
         }
     }
 
+    /// For rustdoc.
+    pub fn get_partial_res(&self, node_id: NodeId) -> Option<PartialRes> {
+        self.partial_res_map.get(&node_id).copied()
+    }
+
     /// Retrieves the span of the given `DefId` if `DefId` is in the local crate.
     #[inline]
     pub fn opt_span(&self, def_id: DefId) -> Option<Span> {
@@ -1994,11 +2021,7 @@ impl<'a> Resolver<'a> {
 
     // Items that go to reexport table encoded to metadata and visible through it to other crates.
     fn is_reexport(&self, binding: &NameBinding<'a>) -> Option<def::Res<!>> {
-        // FIXME: Consider changing the binding inserted by `#[macro_export] macro_rules`
-        // into the crate root to actual `NameBindingKind::Import`.
-        if binding.is_import()
-            || matches!(binding.kind, NameBindingKind::Res(_, _is_macro_export @ true))
-        {
+        if binding.is_import() {
             let res = binding.res().expect_non_local();
             // Ambiguous imports are treated as errors at this point and are
             // not exposed to other crates (see #36837 for more details).
diff --git a/compiler/rustc_resolve/src/macros.rs b/compiler/rustc_resolve/src/macros.rs
index 9526296f9511..8c7972f8eebb 100644
--- a/compiler/rustc_resolve/src/macros.rs
+++ b/compiler/rustc_resolve/src/macros.rs
@@ -356,7 +356,7 @@ impl<'a> ResolverExpand for Resolver<'a> {
             has_derive_copy: false,
         });
         let parent_scope = self.invocation_parent_scopes[&expn_id];
-        for (i, (path, _, opt_ext)) in entry.resolutions.iter_mut().enumerate() {
+        for (i, (path, _, opt_ext, _)) in entry.resolutions.iter_mut().enumerate() {
             if opt_ext.is_none() {
                 *opt_ext = Some(
                     match self.resolve_macro_path(
diff --git a/compiler/rustc_save_analysis/src/dump_visitor.rs b/compiler/rustc_save_analysis/src/dump_visitor.rs
index 23d06d8e5163..df5d992f6633 100644
--- a/compiler/rustc_save_analysis/src/dump_visitor.rs
+++ b/compiler/rustc_save_analysis/src/dump_visitor.rs
@@ -57,7 +57,7 @@ macro_rules! access_from {
     ($save_ctxt:expr, $id:expr) => {
         Access {
             public: $save_ctxt.tcx.visibility($id).is_public(),
-            reachable: $save_ctxt.access_levels.is_reachable($id),
+            reachable: $save_ctxt.effective_visibilities.is_reachable($id),
         }
     };
 }
@@ -345,14 +345,14 @@ impl<'tcx> DumpVisitor<'tcx> {
         body: hir::BodyId,
     ) {
         let map = self.tcx.hir();
-        self.nest_typeck_results(item.def_id.def_id, |v| {
+        self.nest_typeck_results(item.owner_id.def_id, |v| {
             let body = map.body(body);
             if let Some(fn_data) = v.save_ctxt.get_item_data(item) {
                 down_cast_data!(fn_data, DefData, item.span);
                 v.process_formals(body.params, &fn_data.qualname);
                 v.process_generic_params(ty_params, &fn_data.qualname, item.hir_id());
 
-                v.dumper.dump_def(&access_from!(v.save_ctxt, item.def_id.def_id), fn_data);
+                v.dumper.dump_def(&access_from!(v.save_ctxt, item.owner_id.def_id), fn_data);
             }
 
             for arg in decl.inputs {
@@ -373,10 +373,10 @@ impl<'tcx> DumpVisitor<'tcx> {
         typ: &'tcx hir::Ty<'tcx>,
         expr: &'tcx hir::Expr<'tcx>,
     ) {
-        self.nest_typeck_results(item.def_id.def_id, |v| {
+        self.nest_typeck_results(item.owner_id.def_id, |v| {
             if let Some(var_data) = v.save_ctxt.get_item_data(item) {
                 down_cast_data!(var_data, DefData, item.span);
-                v.dumper.dump_def(&access_from!(v.save_ctxt, item.def_id.def_id), var_data);
+                v.dumper.dump_def(&access_from!(v.save_ctxt, item.owner_id.def_id), var_data);
             }
             v.visit_ty(&typ);
             v.visit_expr(expr);
@@ -436,7 +436,7 @@ impl<'tcx> DumpVisitor<'tcx> {
     ) {
         debug!("process_struct {:?} {:?}", item, item.span);
         let name = item.ident.to_string();
-        let qualname = format!("::{}", self.tcx.def_path_str(item.def_id.to_def_id()));
+        let qualname = format!("::{}", self.tcx.def_path_str(item.owner_id.to_def_id()));
 
         let kind = match item.kind {
             hir::ItemKind::Struct(_, _) => DefKind::Struct,
@@ -473,10 +473,10 @@ impl<'tcx> DumpVisitor<'tcx> {
             let span = self.span_from_span(item.ident.span);
             let attrs = self.tcx.hir().attrs(item.hir_id());
             self.dumper.dump_def(
-                &access_from!(self.save_ctxt, item.def_id.def_id),
+                &access_from!(self.save_ctxt, item.owner_id.def_id),
                 Def {
                     kind,
-                    id: id_from_def_id(item.def_id.to_def_id()),
+                    id: id_from_def_id(item.owner_id.to_def_id()),
                     span,
                     name,
                     qualname: qualname.clone(),
@@ -491,7 +491,7 @@ impl<'tcx> DumpVisitor<'tcx> {
             );
         }
 
-        self.nest_typeck_results(item.def_id.def_id, |v| {
+        self.nest_typeck_results(item.owner_id.def_id, |v| {
             for field in def.fields() {
                 v.process_struct_field_def(field, item.hir_id());
                 v.visit_ty(&field.ty);
@@ -513,7 +513,7 @@ impl<'tcx> DumpVisitor<'tcx> {
         };
         down_cast_data!(enum_data, DefData, item.span);
 
-        let access = access_from!(self.save_ctxt, item.def_id.def_id);
+        let access = access_from!(self.save_ctxt, item.owner_id.def_id);
 
         for variant in enum_definition.variants {
             let name = variant.ident.name.to_string();
@@ -528,7 +528,7 @@ impl<'tcx> DumpVisitor<'tcx> {
                     if !self.span.filter_generated(name_span) {
                         let span = self.span_from_span(name_span);
                         let id = id_from_hir_id(variant.id, &self.save_ctxt);
-                        let parent = Some(id_from_def_id(item.def_id.to_def_id()));
+                        let parent = Some(id_from_def_id(item.owner_id.to_def_id()));
                         let attrs = self.tcx.hir().attrs(variant.id);
 
                         self.dumper.dump_def(
@@ -566,7 +566,7 @@ impl<'tcx> DumpVisitor<'tcx> {
                     if !self.span.filter_generated(name_span) {
                         let span = self.span_from_span(name_span);
                         let id = id_from_hir_id(variant.id, &self.save_ctxt);
-                        let parent = Some(id_from_def_id(item.def_id.to_def_id()));
+                        let parent = Some(id_from_def_id(item.owner_id.to_def_id()));
                         let attrs = self.tcx.hir().attrs(variant.id);
 
                         self.dumper.dump_def(
@@ -612,14 +612,14 @@ impl<'tcx> DumpVisitor<'tcx> {
         }
 
         let map = self.tcx.hir();
-        self.nest_typeck_results(item.def_id.def_id, |v| {
+        self.nest_typeck_results(item.owner_id.def_id, |v| {
             v.visit_ty(&impl_.self_ty);
             if let Some(trait_ref) = &impl_.of_trait {
                 v.process_path(trait_ref.hir_ref_id, &hir::QPath::Resolved(None, &trait_ref.path));
             }
             v.process_generic_params(&impl_.generics, "", item.hir_id());
             for impl_item in impl_.items {
-                v.process_impl_item(map.impl_item(impl_item.id), item.def_id.to_def_id());
+                v.process_impl_item(map.impl_item(impl_item.id), item.owner_id.to_def_id());
             }
         });
     }
@@ -632,7 +632,7 @@ impl<'tcx> DumpVisitor<'tcx> {
         methods: &'tcx [hir::TraitItemRef],
     ) {
         let name = item.ident.to_string();
-        let qualname = format!("::{}", self.tcx.def_path_str(item.def_id.to_def_id()));
+        let qualname = format!("::{}", self.tcx.def_path_str(item.owner_id.to_def_id()));
         let mut val = name.clone();
         if !generics.params.is_empty() {
             val.push_str(&generic_params_to_string(generics.params));
@@ -642,13 +642,13 @@ impl<'tcx> DumpVisitor<'tcx> {
             val.push_str(&bounds_to_string(trait_refs));
         }
         if !self.span.filter_generated(item.ident.span) {
-            let id = id_from_def_id(item.def_id.to_def_id());
+            let id = id_from_def_id(item.owner_id.to_def_id());
             let span = self.span_from_span(item.ident.span);
             let children =
-                methods.iter().map(|i| id_from_def_id(i.id.def_id.to_def_id())).collect();
+                methods.iter().map(|i| id_from_def_id(i.id.owner_id.to_def_id())).collect();
             let attrs = self.tcx.hir().attrs(item.hir_id());
             self.dumper.dump_def(
-                &access_from!(self.save_ctxt, item.def_id.def_id),
+                &access_from!(self.save_ctxt, item.owner_id.def_id),
                 Def {
                     kind: DefKind::Trait,
                     id,
@@ -692,7 +692,7 @@ impl<'tcx> DumpVisitor<'tcx> {
                         kind: RelationKind::SuperTrait,
                         span,
                         from: id_from_def_id(id),
-                        to: id_from_def_id(item.def_id.to_def_id()),
+                        to: id_from_def_id(item.owner_id.to_def_id()),
                     });
                 }
             }
@@ -702,7 +702,7 @@ impl<'tcx> DumpVisitor<'tcx> {
         self.process_generic_params(generics, &qualname, item.hir_id());
         for method in methods {
             let map = self.tcx.hir();
-            self.process_trait_item(map.trait_item(method.id), item.def_id.to_def_id())
+            self.process_trait_item(map.trait_item(method.id), item.owner_id.to_def_id())
         }
     }
 
@@ -710,7 +710,7 @@ impl<'tcx> DumpVisitor<'tcx> {
     fn process_mod(&mut self, item: &'tcx hir::Item<'tcx>) {
         if let Some(mod_data) = self.save_ctxt.get_item_data(item) {
             down_cast_data!(mod_data, DefData, item.span);
-            self.dumper.dump_def(&access_from!(self.save_ctxt, item.def_id.def_id), mod_data);
+            self.dumper.dump_def(&access_from!(self.save_ctxt, item.owner_id.def_id), mod_data);
         }
     }
 
@@ -981,7 +981,7 @@ impl<'tcx> DumpVisitor<'tcx> {
                 let body = body.map(|b| self.tcx.hir().body(b).value);
                 let attrs = self.tcx.hir().attrs(trait_item.hir_id());
                 self.process_assoc_const(
-                    trait_item.def_id.def_id,
+                    trait_item.owner_id.def_id,
                     trait_item.ident,
                     &ty,
                     body,
@@ -995,7 +995,7 @@ impl<'tcx> DumpVisitor<'tcx> {
                 self.process_method(
                     sig,
                     body,
-                    trait_item.def_id.def_id,
+                    trait_item.owner_id.def_id,
                     trait_item.ident,
                     &trait_item.generics,
                     trait_item.span,
@@ -1005,11 +1005,11 @@ impl<'tcx> DumpVisitor<'tcx> {
                 // FIXME do something with _bounds (for type refs)
                 let name = trait_item.ident.name.to_string();
                 let qualname =
-                    format!("::{}", self.tcx.def_path_str(trait_item.def_id.to_def_id()));
+                    format!("::{}", self.tcx.def_path_str(trait_item.owner_id.to_def_id()));
 
                 if !self.span.filter_generated(trait_item.ident.span) {
                     let span = self.span_from_span(trait_item.ident.span);
-                    let id = id_from_def_id(trait_item.def_id.to_def_id());
+                    let id = id_from_def_id(trait_item.owner_id.to_def_id());
                     let attrs = self.tcx.hir().attrs(trait_item.hir_id());
 
                     self.dumper.dump_def(
@@ -1051,7 +1051,7 @@ impl<'tcx> DumpVisitor<'tcx> {
                 let body = self.tcx.hir().body(body);
                 let attrs = self.tcx.hir().attrs(impl_item.hir_id());
                 self.process_assoc_const(
-                    impl_item.def_id.def_id,
+                    impl_item.owner_id.def_id,
                     impl_item.ident,
                     &ty,
                     Some(&body.value),
@@ -1063,7 +1063,7 @@ impl<'tcx> DumpVisitor<'tcx> {
                 self.process_method(
                     sig,
                     Some(body),
-                    impl_item.def_id.def_id,
+                    impl_item.owner_id.def_id,
                     impl_item.ident,
                     &impl_item.generics,
                     impl_item.span,
@@ -1088,7 +1088,7 @@ impl<'tcx> DumpVisitor<'tcx> {
         let filename = sm.span_to_filename(krate_mod.spans.inner_span);
         let data_id = id_from_hir_id(id, &self.save_ctxt);
         let children =
-            krate_mod.item_ids.iter().map(|i| id_from_def_id(i.def_id.to_def_id())).collect();
+            krate_mod.item_ids.iter().map(|i| id_from_def_id(i.owner_id.to_def_id())).collect();
         let span = self.span_from_span(krate_mod.spans.inner_span);
         let attrs = self.tcx.hir().attrs(id);
 
@@ -1137,10 +1137,10 @@ impl<'tcx> Visitor<'tcx> for DumpVisitor<'tcx> {
             hir::ItemKind::Use(path, hir::UseKind::Single) => {
                 let sub_span = path.segments.last().unwrap().ident.span;
                 if !self.span.filter_generated(sub_span) {
-                    let access = access_from!(self.save_ctxt, item.def_id.def_id);
+                    let access = access_from!(self.save_ctxt, item.owner_id.def_id);
                     let ref_id = self.lookup_def_id(item.hir_id()).map(id_from_def_id);
                     let span = self.span_from_span(sub_span);
-                    let parent = self.save_ctxt.tcx.local_parent(item.def_id.def_id);
+                    let parent = self.save_ctxt.tcx.local_parent(item.owner_id.def_id);
                     self.dumper.import(
                         &access,
                         Import {
@@ -1158,16 +1158,16 @@ impl<'tcx> Visitor<'tcx> for DumpVisitor<'tcx> {
             }
             hir::ItemKind::Use(path, hir::UseKind::Glob) => {
                 // Make a comma-separated list of names of imported modules.
-                let names = self.tcx.names_imported_by_glob_use(item.def_id.def_id);
+                let names = self.tcx.names_imported_by_glob_use(item.owner_id.def_id);
                 let names: Vec<_> = names.iter().map(|n| n.to_string()).collect();
 
                 // Otherwise it's a span with wrong macro expansion info, which
                 // we don't want to track anyway, since it's probably macro-internal `use`
                 if let Some(sub_span) = self.span.sub_span_of_star(item.span) {
                     if !self.span.filter_generated(item.span) {
-                        let access = access_from!(self.save_ctxt, item.def_id.def_id);
+                        let access = access_from!(self.save_ctxt, item.owner_id.def_id);
                         let span = self.span_from_span(sub_span);
-                        let parent = self.save_ctxt.tcx.local_parent(item.def_id.def_id);
+                        let parent = self.save_ctxt.tcx.local_parent(item.owner_id.def_id);
                         self.dumper.import(
                             &access,
                             Import {
@@ -1188,7 +1188,7 @@ impl<'tcx> Visitor<'tcx> for DumpVisitor<'tcx> {
                 let name_span = item.ident.span;
                 if !self.span.filter_generated(name_span) {
                     let span = self.span_from_span(name_span);
-                    let parent = self.save_ctxt.tcx.local_parent(item.def_id.def_id);
+                    let parent = self.save_ctxt.tcx.local_parent(item.owner_id.def_id);
                     self.dumper.import(
                         &Access { public: false, reachable: false },
                         Import {
@@ -1228,15 +1228,15 @@ impl<'tcx> Visitor<'tcx> for DumpVisitor<'tcx> {
                 intravisit::walk_mod(self, m, item.hir_id());
             }
             hir::ItemKind::TyAlias(ty, ref generics) => {
-                let qualname = format!("::{}", self.tcx.def_path_str(item.def_id.to_def_id()));
+                let qualname = format!("::{}", self.tcx.def_path_str(item.owner_id.to_def_id()));
                 let value = ty_to_string(&ty);
                 if !self.span.filter_generated(item.ident.span) {
                     let span = self.span_from_span(item.ident.span);
-                    let id = id_from_def_id(item.def_id.to_def_id());
+                    let id = id_from_def_id(item.owner_id.to_def_id());
                     let attrs = self.tcx.hir().attrs(item.hir_id());
 
                     self.dumper.dump_def(
-                        &access_from!(self.save_ctxt, item.def_id.def_id),
+                        &access_from!(self.save_ctxt, item.owner_id.def_id),
                         Def {
                             kind: DefKind::Type,
                             id,
@@ -1324,7 +1324,7 @@ impl<'tcx> Visitor<'tcx> for DumpVisitor<'tcx> {
             }
             hir::TyKind::OpaqueDef(item_id, _, _) => {
                 let item = self.tcx.hir().item(item_id);
-                self.nest_typeck_results(item_id.def_id.def_id, |v| v.visit_item(item));
+                self.nest_typeck_results(item_id.owner_id.def_id, |v| v.visit_item(item));
             }
             _ => intravisit::walk_ty(self, t),
         }
@@ -1431,7 +1431,7 @@ impl<'tcx> Visitor<'tcx> for DumpVisitor<'tcx> {
     }
 
     fn visit_foreign_item(&mut self, item: &'tcx hir::ForeignItem<'tcx>) {
-        let access = access_from!(self.save_ctxt, item.def_id.def_id);
+        let access = access_from!(self.save_ctxt, item.owner_id.def_id);
 
         match item.kind {
             hir::ForeignItemKind::Fn(decl, _, ref generics) => {
diff --git a/compiler/rustc_save_analysis/src/lib.rs b/compiler/rustc_save_analysis/src/lib.rs
index aa000b7067bd..d0155c908a2b 100644
--- a/compiler/rustc_save_analysis/src/lib.rs
+++ b/compiler/rustc_save_analysis/src/lib.rs
@@ -26,7 +26,7 @@ use rustc_hir::intravisit::{self, Visitor};
 use rustc_hir::Node;
 use rustc_hir_pretty::{enum_def_to_string, fn_to_string, ty_to_string};
 use rustc_middle::hir::nested_filter;
-use rustc_middle::middle::privacy::AccessLevels;
+use rustc_middle::middle::privacy::EffectiveVisibilities;
 use rustc_middle::ty::{self, print::with_no_trimmed_paths, DefIdTree, TyCtxt};
 use rustc_middle::{bug, span_bug};
 use rustc_session::config::{CrateType, Input, OutputType};
@@ -54,7 +54,7 @@ use rls_data::{
 pub struct SaveContext<'tcx> {
     tcx: TyCtxt<'tcx>,
     maybe_typeck_results: Option<&'tcx ty::TypeckResults<'tcx>>,
-    access_levels: &'tcx AccessLevels,
+    effective_visibilities: &'tcx EffectiveVisibilities,
     span_utils: SpanUtils<'tcx>,
     config: Config,
     impl_counter: Cell<u32>,
@@ -141,7 +141,7 @@ impl<'tcx> SaveContext<'tcx> {
     }
 
     pub fn get_extern_item_data(&self, item: &hir::ForeignItem<'_>) -> Option<Data> {
-        let def_id = item.def_id.to_def_id();
+        let def_id = item.owner_id.to_def_id();
         let qualname = format!("::{}", self.tcx.def_path_str(def_id));
         let attrs = self.tcx.hir().attrs(item.hir_id());
         match item.kind {
@@ -205,7 +205,7 @@ impl<'tcx> SaveContext<'tcx> {
     }
 
     pub fn get_item_data(&self, item: &hir::Item<'_>) -> Option<Data> {
-        let def_id = item.def_id.to_def_id();
+        let def_id = item.owner_id.to_def_id();
         let attrs = self.tcx.hir().attrs(item.hir_id());
         match item.kind {
             hir::ItemKind::Fn(ref sig, ref generics, _) => {
@@ -297,7 +297,7 @@ impl<'tcx> SaveContext<'tcx> {
                     children: m
                         .item_ids
                         .iter()
-                        .map(|i| id_from_def_id(i.def_id.to_def_id()))
+                        .map(|i| id_from_def_id(i.owner_id.to_def_id()))
                         .collect(),
                     decl_id: None,
                     docs: self.docs_for_attrs(attrs),
@@ -363,7 +363,7 @@ impl<'tcx> SaveContext<'tcx> {
                             parent: None,
                             children: items
                                 .iter()
-                                .map(|i| id_from_def_id(i.id.def_id.to_def_id()))
+                                .map(|i| id_from_def_id(i.id.owner_id.to_def_id()))
                                 .collect(),
                             docs: String::new(),
                             sig: None,
@@ -968,16 +968,16 @@ pub fn process_crate<'l, 'tcx, H: SaveHandler>(
             info!("Dumping crate {}", cratename);
 
             // Privacy checking must be done outside of type inference; use a
-            // fallback in case the access levels couldn't have been correctly computed.
-            let access_levels = match tcx.sess.compile_status() {
-                Ok(..) => tcx.privacy_access_levels(()),
-                Err(..) => tcx.arena.alloc(AccessLevels::default()),
+            // fallback in case effective visibilities couldn't have been correctly computed.
+            let effective_visibilities = match tcx.sess.compile_status() {
+                Ok(..) => tcx.effective_visibilities(()),
+                Err(..) => tcx.arena.alloc(EffectiveVisibilities::default()),
             };
 
             let save_ctxt = SaveContext {
                 tcx,
                 maybe_typeck_results: None,
-                access_levels: &access_levels,
+                effective_visibilities: &effective_visibilities,
                 span_utils: SpanUtils::new(&tcx.sess),
                 config: find_config(config),
                 impl_counter: Cell::new(0),
diff --git a/compiler/rustc_save_analysis/src/sig.rs b/compiler/rustc_save_analysis/src/sig.rs
index 62e9f6520fbb..83c51d213be3 100644
--- a/compiler/rustc_save_analysis/src/sig.rs
+++ b/compiler/rustc_save_analysis/src/sig.rs
@@ -337,7 +337,7 @@ impl<'hir> Sig for hir::Item<'hir> {
                 }
                 let name = self.ident.to_string();
                 let defs = vec![SigElement {
-                    id: id_from_def_id(self.def_id.to_def_id()),
+                    id: id_from_def_id(self.owner_id.to_def_id()),
                     start: offset + text.len(),
                     end: offset + text.len() + name.len(),
                 }];
@@ -359,7 +359,7 @@ impl<'hir> Sig for hir::Item<'hir> {
                 let mut text = "const ".to_owned();
                 let name = self.ident.to_string();
                 let defs = vec![SigElement {
-                    id: id_from_def_id(self.def_id.to_def_id()),
+                    id: id_from_def_id(self.owner_id.to_def_id()),
                     start: offset + text.len(),
                     end: offset + text.len() + name.len(),
                 }];
@@ -428,7 +428,7 @@ impl<'hir> Sig for hir::Item<'hir> {
                 let mut text = "mod ".to_owned();
                 let name = self.ident.to_string();
                 let defs = vec![SigElement {
-                    id: id_from_def_id(self.def_id.to_def_id()),
+                    id: id_from_def_id(self.owner_id.to_def_id()),
                     start: offset + text.len(),
                     end: offset + text.len() + name.len(),
                 }];
@@ -764,7 +764,7 @@ impl<'hir> Sig for hir::ForeignItem<'hir> {
                 }
                 let name = self.ident.to_string();
                 let defs = vec![SigElement {
-                    id: id_from_def_id(self.def_id.to_def_id()),
+                    id: id_from_def_id(self.owner_id.to_def_id()),
                     start: offset + text.len(),
                     end: offset + text.len() + name.len(),
                 }];
@@ -780,7 +780,7 @@ impl<'hir> Sig for hir::ForeignItem<'hir> {
                 let mut text = "type ".to_owned();
                 let name = self.ident.to_string();
                 let defs = vec![SigElement {
-                    id: id_from_def_id(self.def_id.to_def_id()),
+                    id: id_from_def_id(self.owner_id.to_def_id()),
                     start: offset + text.len(),
                     end: offset + text.len() + name.len(),
                 }];
diff --git a/compiler/rustc_serialize/Cargo.toml b/compiler/rustc_serialize/Cargo.toml
index 3b0b3144f2cd..db0ef73544fa 100644
--- a/compiler/rustc_serialize/Cargo.toml
+++ b/compiler/rustc_serialize/Cargo.toml
@@ -6,7 +6,7 @@ edition = "2021"
 [dependencies]
 indexmap = "1.9.1"
 smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
-thin-vec = "0.2.8"
+thin-vec = "0.2.9"
 
 [dev-dependencies]
 rustc_macros = { path = "../rustc_macros" }
diff --git a/compiler/rustc_session/Cargo.toml b/compiler/rustc_session/Cargo.toml
index 6b1eaa4d399d..a052f2933416 100644
--- a/compiler/rustc_session/Cargo.toml
+++ b/compiler/rustc_session/Cargo.toml
@@ -17,3 +17,10 @@ rustc_span = { path = "../rustc_span" }
 rustc_fs_util = { path = "../rustc_fs_util" }
 rustc_ast = { path = "../rustc_ast" }
 rustc_lint_defs = { path = "../rustc_lint_defs" }
+smallvec = "1.8.1"
+
+[target.'cfg(unix)'.dependencies]
+libc = "0.2"
+
+[target.'cfg(windows)'.dependencies]
+winapi = { version = "0.3", features = ["libloaderapi"] }
diff --git a/compiler/rustc_session/src/config.rs b/compiler/rustc_session/src/config.rs
index f2ee52262ade..be084adb7b72 100644
--- a/compiler/rustc_session/src/config.rs
+++ b/compiler/rustc_session/src/config.rs
@@ -548,6 +548,7 @@ pub enum PrintRequest {
     NativeStaticLibs,
     StackProtectorStrategies,
     LinkArgs,
+    SplitDebuginfo,
 }
 
 pub enum Input {
@@ -738,7 +739,7 @@ impl Default for Options {
             actually_rustdoc: false,
             trimmed_def_paths: TrimmedDefPaths::default(),
             cli_forced_codegen_units: None,
-            cli_forced_thinlto_off: false,
+            cli_forced_local_thinlto_off: false,
             remap_path_prefix: Vec::new(),
             real_rust_source_base_dir: None,
             edition: DEFAULT_EDITION,
@@ -794,6 +795,7 @@ impl UnstableOptions {
             report_delayed_bugs: self.report_delayed_bugs,
             macro_backtrace: self.macro_backtrace,
             deduplicate_diagnostics: self.deduplicate_diagnostics,
+            track_diagnostics: self.track_diagnostics,
         }
     }
 }
@@ -1720,7 +1722,7 @@ fn should_override_cgus_and_disable_thinlto(
     error_format: ErrorOutputType,
     mut codegen_units: Option<usize>,
 ) -> (bool, Option<usize>) {
-    let mut disable_thinlto = false;
+    let mut disable_local_thinlto = false;
     // Issue #30063: if user requests LLVM-related output to one
     // particular path, disable codegen-units.
     let incompatible: Vec<_> = output_types
@@ -1745,12 +1747,12 @@ fn should_override_cgus_and_disable_thinlto(
                     }
                     early_warn(error_format, "resetting to default -C codegen-units=1");
                     codegen_units = Some(1);
-                    disable_thinlto = true;
+                    disable_local_thinlto = true;
                 }
             }
             _ => {
                 codegen_units = Some(1);
-                disable_thinlto = true;
+                disable_local_thinlto = true;
             }
         }
     }
@@ -1759,7 +1761,7 @@ fn should_override_cgus_and_disable_thinlto(
         early_error(error_format, "value for codegen units must be a positive non-zero integer");
     }
 
-    (disable_thinlto, codegen_units)
+    (disable_local_thinlto, codegen_units)
 }
 
 fn check_thread_count(unstable_opts: &UnstableOptions, error_format: ErrorOutputType) {
@@ -1788,34 +1790,50 @@ fn collect_print_requests(
         cg.target_feature = String::new();
     }
 
-    prints.extend(matches.opt_strs("print").into_iter().map(|s| match &*s {
-        "crate-name" => PrintRequest::CrateName,
-        "file-names" => PrintRequest::FileNames,
-        "sysroot" => PrintRequest::Sysroot,
-        "target-libdir" => PrintRequest::TargetLibdir,
-        "cfg" => PrintRequest::Cfg,
-        "calling-conventions" => PrintRequest::CallingConventions,
-        "target-list" => PrintRequest::TargetList,
-        "target-cpus" => PrintRequest::TargetCPUs,
-        "target-features" => PrintRequest::TargetFeatures,
-        "relocation-models" => PrintRequest::RelocationModels,
-        "code-models" => PrintRequest::CodeModels,
-        "tls-models" => PrintRequest::TlsModels,
-        "native-static-libs" => PrintRequest::NativeStaticLibs,
-        "stack-protector-strategies" => PrintRequest::StackProtectorStrategies,
-        "target-spec-json" => {
-            if unstable_opts.unstable_options {
-                PrintRequest::TargetSpec
-            } else {
+    const PRINT_REQUESTS: &[(&str, PrintRequest)] = &[
+        ("crate-name", PrintRequest::CrateName),
+        ("file-names", PrintRequest::FileNames),
+        ("sysroot", PrintRequest::Sysroot),
+        ("target-libdir", PrintRequest::TargetLibdir),
+        ("cfg", PrintRequest::Cfg),
+        ("calling-conventions", PrintRequest::CallingConventions),
+        ("target-list", PrintRequest::TargetList),
+        ("target-cpus", PrintRequest::TargetCPUs),
+        ("target-features", PrintRequest::TargetFeatures),
+        ("relocation-models", PrintRequest::RelocationModels),
+        ("code-models", PrintRequest::CodeModels),
+        ("tls-models", PrintRequest::TlsModels),
+        ("native-static-libs", PrintRequest::NativeStaticLibs),
+        ("stack-protector-strategies", PrintRequest::StackProtectorStrategies),
+        ("target-spec-json", PrintRequest::TargetSpec),
+        ("link-args", PrintRequest::LinkArgs),
+        ("split-debuginfo", PrintRequest::SplitDebuginfo),
+    ];
+
+    prints.extend(matches.opt_strs("print").into_iter().map(|req| {
+        match PRINT_REQUESTS.iter().find(|&&(name, _)| name == req) {
+            Some((_, PrintRequest::TargetSpec)) => {
+                if unstable_opts.unstable_options {
+                    PrintRequest::TargetSpec
+                } else {
+                    early_error(
+                        error_format,
+                        "the `-Z unstable-options` flag must also be passed to \
+                     enable the target-spec-json print option",
+                    );
+                }
+            }
+            Some(&(_, print_request)) => print_request,
+            None => {
+                let prints =
+                    PRINT_REQUESTS.iter().map(|(name, _)| format!("`{name}`")).collect::<Vec<_>>();
+                let prints = prints.join(", ");
                 early_error(
                     error_format,
-                    "the `-Z unstable-options` flag must also be passed to \
-                     enable the target-spec-json print option",
+                    &format!("unknown print request `{req}`. Valid print requests are: {prints}"),
                 );
             }
         }
-        "link-args" => PrintRequest::LinkArgs,
-        req => early_error(error_format, &format!("unknown print request `{req}`")),
     }));
 
     prints
@@ -2249,7 +2267,7 @@ pub fn build_session_options(matches: &getopts::Matches) -> Options {
     let output_types = parse_output_types(&unstable_opts, matches, error_format);
 
     let mut cg = CodegenOptions::build(matches, error_format);
-    let (disable_thinlto, mut codegen_units) = should_override_cgus_and_disable_thinlto(
+    let (disable_local_thinlto, mut codegen_units) = should_override_cgus_and_disable_thinlto(
         &output_types,
         matches,
         error_format,
@@ -2431,7 +2449,7 @@ pub fn build_session_options(matches: &getopts::Matches) -> Options {
     let sysroot = match &sysroot_opt {
         Some(s) => s,
         None => {
-            tmp_buf = crate::filesearch::get_or_default_sysroot();
+            tmp_buf = crate::filesearch::get_or_default_sysroot().expect("Failed finding sysroot");
             &tmp_buf
         }
     };
@@ -2492,7 +2510,7 @@ pub fn build_session_options(matches: &getopts::Matches) -> Options {
         actually_rustdoc: false,
         trimmed_def_paths: TrimmedDefPaths::default(),
         cli_forced_codegen_units: codegen_units,
-        cli_forced_thinlto_off: disable_thinlto,
+        cli_forced_local_thinlto_off: disable_local_thinlto,
         remap_path_prefix,
         real_rust_source_base_dir,
         edition,
diff --git a/compiler/rustc_session/src/filesearch.rs b/compiler/rustc_session/src/filesearch.rs
index e8edb38f5038..1b66773be6f0 100644
--- a/compiler/rustc_session/src/filesearch.rs
+++ b/compiler/rustc_session/src/filesearch.rs
@@ -1,5 +1,6 @@
 //! A module for searching for libraries
 
+use smallvec::{smallvec, SmallVec};
 use std::env;
 use std::fs;
 use std::iter::FromIterator;
@@ -62,9 +63,99 @@ pub fn make_target_lib_path(sysroot: &Path, target_triple: &str) -> PathBuf {
     PathBuf::from_iter([sysroot, Path::new(&rustlib_path), Path::new("lib")])
 }
 
+#[cfg(unix)]
+fn current_dll_path() -> Result<PathBuf, String> {
+    use std::ffi::{CStr, OsStr};
+    use std::os::unix::prelude::*;
+
+    unsafe {
+        let addr = current_dll_path as usize as *mut _;
+        let mut info = std::mem::zeroed();
+        if libc::dladdr(addr, &mut info) == 0 {
+            return Err("dladdr failed".into());
+        }
+        if info.dli_fname.is_null() {
+            return Err("dladdr returned null pointer".into());
+        }
+        let bytes = CStr::from_ptr(info.dli_fname).to_bytes();
+        let os = OsStr::from_bytes(bytes);
+        Ok(PathBuf::from(os))
+    }
+}
+
+#[cfg(windows)]
+fn current_dll_path() -> Result<PathBuf, String> {
+    use std::ffi::OsString;
+    use std::io;
+    use std::os::windows::prelude::*;
+    use std::ptr;
+
+    use winapi::um::libloaderapi::{
+        GetModuleFileNameW, GetModuleHandleExW, GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS,
+    };
+
+    unsafe {
+        let mut module = ptr::null_mut();
+        let r = GetModuleHandleExW(
+            GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS,
+            current_dll_path as usize as *mut _,
+            &mut module,
+        );
+        if r == 0 {
+            return Err(format!("GetModuleHandleExW failed: {}", io::Error::last_os_error()));
+        }
+        let mut space = Vec::with_capacity(1024);
+        let r = GetModuleFileNameW(module, space.as_mut_ptr(), space.capacity() as u32);
+        if r == 0 {
+            return Err(format!("GetModuleFileNameW failed: {}", io::Error::last_os_error()));
+        }
+        let r = r as usize;
+        if r >= space.capacity() {
+            return Err(format!("our buffer was too small? {}", io::Error::last_os_error()));
+        }
+        space.set_len(r);
+        let os = OsString::from_wide(&space);
+        Ok(PathBuf::from(os))
+    }
+}
+
+pub fn sysroot_candidates() -> SmallVec<[PathBuf; 2]> {
+    let target = crate::config::host_triple();
+    let mut sysroot_candidates: SmallVec<[PathBuf; 2]> =
+        smallvec![get_or_default_sysroot().expect("Failed finding sysroot")];
+    let path = current_dll_path().and_then(|s| Ok(s.canonicalize().map_err(|e| e.to_string())?));
+    if let Ok(dll) = path {
+        // use `parent` twice to chop off the file name and then also the
+        // directory containing the dll which should be either `lib` or `bin`.
+        if let Some(path) = dll.parent().and_then(|p| p.parent()) {
+            // The original `path` pointed at the `rustc_driver` crate's dll.
+            // Now that dll should only be in one of two locations. The first is
+            // in the compiler's libdir, for example `$sysroot/lib/*.dll`. The
+            // other is the target's libdir, for example
+            // `$sysroot/lib/rustlib/$target/lib/*.dll`.
+            //
+            // We don't know which, so let's assume that if our `path` above
+            // ends in `$target` we *could* be in the target libdir, and always
+            // assume that we may be in the main libdir.
+            sysroot_candidates.push(path.to_owned());
+
+            if path.ends_with(target) {
+                sysroot_candidates.extend(
+                    path.parent() // chop off `$target`
+                        .and_then(|p| p.parent()) // chop off `rustlib`
+                        .and_then(|p| p.parent()) // chop off `lib`
+                        .map(|s| s.to_owned()),
+                );
+            }
+        }
+    }
+
+    return sysroot_candidates;
+}
+
 /// This function checks if sysroot is found using env::args().next(), and if it
-/// is not found, uses env::current_exe() to imply sysroot.
-pub fn get_or_default_sysroot() -> PathBuf {
+/// is not found, finds sysroot from current rustc_driver dll.
+pub fn get_or_default_sysroot() -> Result<PathBuf, String> {
     // Follow symlinks.  If the resolved path is relative, make it absolute.
     fn canonicalize(path: PathBuf) -> PathBuf {
         let path = fs::canonicalize(&path).unwrap_or(path);
@@ -74,17 +165,32 @@ pub fn get_or_default_sysroot() -> PathBuf {
         fix_windows_verbatim_for_gcc(&path)
     }
 
-    // Use env::current_exe() to get the path of the executable following
-    // symlinks/canonicalizing components.
-    fn from_current_exe() -> PathBuf {
-        match env::current_exe() {
-            Ok(exe) => {
-                let mut p = canonicalize(exe);
-                p.pop();
-                p.pop();
-                p
-            }
-            Err(e) => panic!("failed to get current_exe: {e}"),
+    fn default_from_rustc_driver_dll() -> Result<PathBuf, String> {
+        let dll = current_dll_path().and_then(|s| Ok(canonicalize(s)))?;
+
+        // `dll` will be in one of the following two:
+        // - compiler's libdir: $sysroot/lib/*.dll
+        // - target's libdir: $sysroot/lib/rustlib/$target/lib/*.dll
+        //
+        // use `parent` twice to chop off the file name and then also the
+        // directory containing the dll
+        let dir = dll.parent().and_then(|p| p.parent()).ok_or(format!(
+            "Could not move 2 levels upper using `parent()` on {}",
+            dll.display()
+        ))?;
+
+        // if `dir` points target's dir, move up to the sysroot
+        if dir.ends_with(crate::config::host_triple()) {
+            dir.parent() // chop off `$target`
+                .and_then(|p| p.parent()) // chop off `rustlib`
+                .and_then(|p| p.parent()) // chop off `lib`
+                .map(|s| s.to_owned())
+                .ok_or(format!(
+                    "Could not move 3 levels upper using `parent()` on {}",
+                    dir.display()
+                ))
+        } else {
+            Ok(dir.to_owned())
         }
     }
 
@@ -118,7 +224,5 @@ pub fn get_or_default_sysroot() -> PathBuf {
         }
     }
 
-    // Check if sysroot is found using env::args().next(), and if is not found,
-    // use env::current_exe() to imply sysroot.
-    from_env_args_next().unwrap_or_else(from_current_exe)
+    Ok(from_env_args_next().unwrap_or(default_from_rustc_driver_dll()?))
 }
diff --git a/compiler/rustc_session/src/options.rs b/compiler/rustc_session/src/options.rs
index 3f234a47a3d8..f9ee202466f6 100644
--- a/compiler/rustc_session/src/options.rs
+++ b/compiler/rustc_session/src/options.rs
@@ -181,7 +181,7 @@ top_level_options!(
         #[rustc_lint_opt_deny_field_access("use `Session::codegen_units` instead of this field")]
         cli_forced_codegen_units: Option<usize> [UNTRACKED],
         #[rustc_lint_opt_deny_field_access("use `Session::lto` instead of this field")]
-        cli_forced_thinlto_off: bool [UNTRACKED],
+        cli_forced_local_thinlto_off: bool [UNTRACKED],
 
         /// Remap source path prefixes in all output (messages, object files, debug, etc.).
         remap_path_prefix: Vec<(PathBuf, PathBuf)> [TRACKED_NO_CRATE_HASH],
@@ -1587,6 +1587,8 @@ options! {
         "choose the TLS model to use (`rustc --print tls-models` for details)"),
     trace_macros: bool = (false, parse_bool, [UNTRACKED],
         "for every macro invocation, print its name and arguments (default: no)"),
+    track_diagnostics: bool = (false, parse_bool, [UNTRACKED],
+        "tracks where in rustc a diagnostic was emitted"),
     // Diagnostics are considered side-effects of a query (see `QuerySideEffects`) and are saved
     // alongside query results and changes to translation options can affect diagnostics - so
     // translation options should be tracked.
diff --git a/compiler/rustc_session/src/parse.rs b/compiler/rustc_session/src/parse.rs
index a199947ebed0..f9f4f2979c4e 100644
--- a/compiler/rustc_session/src/parse.rs
+++ b/compiler/rustc_session/src/parse.rs
@@ -97,6 +97,7 @@ pub fn feature_err<'a>(
 ///
 /// This variant allows you to control whether it is a library or language feature.
 /// Almost always, you want to use this for a language feature. If so, prefer `feature_err`.
+#[track_caller]
 pub fn feature_err_issue<'a>(
     sess: &'a ParseSess,
     feature: Symbol,
@@ -332,6 +333,7 @@ impl ParseSess {
         self.proc_macro_quoted_spans.lock().clone()
     }
 
+    #[track_caller]
     pub fn create_err<'a>(
         &'a self,
         err: impl IntoDiagnostic<'a>,
@@ -339,10 +341,12 @@ impl ParseSess {
         err.into_diagnostic(&self.span_diagnostic)
     }
 
+    #[track_caller]
     pub fn emit_err<'a>(&'a self, err: impl IntoDiagnostic<'a>) -> ErrorGuaranteed {
         self.create_err(err).emit()
     }
 
+    #[track_caller]
     pub fn create_warning<'a>(
         &'a self,
         warning: impl IntoDiagnostic<'a, ()>,
@@ -350,6 +354,7 @@ impl ParseSess {
         warning.into_diagnostic(&self.span_diagnostic)
     }
 
+    #[track_caller]
     pub fn emit_warning<'a>(&'a self, warning: impl IntoDiagnostic<'a, ()>) {
         self.create_warning(warning).emit()
     }
@@ -377,6 +382,7 @@ impl ParseSess {
     }
 
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_err(
         &self,
         msg: impl Into<DiagnosticMessage>,
diff --git a/compiler/rustc_session/src/session.rs b/compiler/rustc_session/src/session.rs
index 100c66f63641..103521983578 100644
--- a/compiler/rustc_session/src/session.rs
+++ b/compiler/rustc_session/src/session.rs
@@ -286,6 +286,7 @@ impl Session {
     }
 
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_span_warn<S: Into<MultiSpan>>(
         &self,
         sp: S,
@@ -294,6 +295,7 @@ impl Session {
         self.diagnostic().struct_span_warn(sp, msg)
     }
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_span_warn_with_expectation<S: Into<MultiSpan>>(
         &self,
         sp: S,
@@ -303,6 +305,7 @@ impl Session {
         self.diagnostic().struct_span_warn_with_expectation(sp, msg, id)
     }
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_span_warn_with_code<S: Into<MultiSpan>>(
         &self,
         sp: S,
@@ -312,10 +315,12 @@ impl Session {
         self.diagnostic().struct_span_warn_with_code(sp, msg, code)
     }
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_warn(&self, msg: impl Into<DiagnosticMessage>) -> DiagnosticBuilder<'_, ()> {
         self.diagnostic().struct_warn(msg)
     }
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_warn_with_expectation(
         &self,
         msg: impl Into<DiagnosticMessage>,
@@ -324,6 +329,7 @@ impl Session {
         self.diagnostic().struct_warn_with_expectation(msg, id)
     }
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_span_allow<S: Into<MultiSpan>>(
         &self,
         sp: S,
@@ -332,10 +338,12 @@ impl Session {
         self.diagnostic().struct_span_allow(sp, msg)
     }
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_allow(&self, msg: impl Into<DiagnosticMessage>) -> DiagnosticBuilder<'_, ()> {
         self.diagnostic().struct_allow(msg)
     }
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_expect(
         &self,
         msg: impl Into<DiagnosticMessage>,
@@ -344,6 +352,7 @@ impl Session {
         self.diagnostic().struct_expect(msg, id)
     }
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_span_err<S: Into<MultiSpan>>(
         &self,
         sp: S,
@@ -352,6 +361,7 @@ impl Session {
         self.diagnostic().struct_span_err(sp, msg)
     }
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_span_err_with_code<S: Into<MultiSpan>>(
         &self,
         sp: S,
@@ -362,12 +372,14 @@ impl Session {
     }
     // FIXME: This method should be removed (every error should have an associated error code).
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_err(
         &self,
         msg: impl Into<DiagnosticMessage>,
     ) -> DiagnosticBuilder<'_, ErrorGuaranteed> {
         self.parse_sess.struct_err(msg)
     }
+    #[track_caller]
     #[rustc_lint_diagnostics]
     pub fn struct_err_with_code(
         &self,
@@ -377,6 +389,7 @@ impl Session {
         self.diagnostic().struct_err_with_code(msg, code)
     }
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_warn_with_code(
         &self,
         msg: impl Into<DiagnosticMessage>,
@@ -385,6 +398,7 @@ impl Session {
         self.diagnostic().struct_warn_with_code(msg, code)
     }
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn struct_span_fatal<S: Into<MultiSpan>>(
         &self,
         sp: S,
@@ -407,6 +421,7 @@ impl Session {
     }
 
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn span_fatal<S: Into<MultiSpan>>(&self, sp: S, msg: impl Into<DiagnosticMessage>) -> ! {
         self.diagnostic().span_fatal(sp, msg)
     }
@@ -424,6 +439,7 @@ impl Session {
         self.diagnostic().fatal(msg).raise()
     }
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn span_err_or_warn<S: Into<MultiSpan>>(
         &self,
         is_warning: bool,
@@ -437,6 +453,7 @@ impl Session {
         }
     }
     #[rustc_lint_diagnostics]
+    #[track_caller]
     pub fn span_err<S: Into<MultiSpan>>(
         &self,
         sp: S,
@@ -457,12 +474,14 @@ impl Session {
     pub fn err(&self, msg: impl Into<DiagnosticMessage>) -> ErrorGuaranteed {
         self.diagnostic().err(msg)
     }
+    #[track_caller]
     pub fn create_err<'a>(
         &'a self,
         err: impl IntoDiagnostic<'a>,
     ) -> DiagnosticBuilder<'a, ErrorGuaranteed> {
         self.parse_sess.create_err(err)
     }
+    #[track_caller]
     pub fn create_feature_err<'a>(
         &'a self,
         err: impl IntoDiagnostic<'a>,
@@ -475,33 +494,40 @@ impl Session {
         add_feature_diagnostics(&mut err, &self.parse_sess, feature);
         err
     }
+    #[track_caller]
     pub fn emit_err<'a>(&'a self, err: impl IntoDiagnostic<'a>) -> ErrorGuaranteed {
         self.parse_sess.emit_err(err)
     }
+    #[track_caller]
     pub fn create_warning<'a>(
         &'a self,
         err: impl IntoDiagnostic<'a, ()>,
     ) -> DiagnosticBuilder<'a, ()> {
         self.parse_sess.create_warning(err)
     }
+    #[track_caller]
     pub fn emit_warning<'a>(&'a self, warning: impl IntoDiagnostic<'a, ()>) {
         self.parse_sess.emit_warning(warning)
     }
+    #[track_caller]
     pub fn create_note<'a>(
         &'a self,
         note: impl IntoDiagnostic<'a, Noted>,
     ) -> DiagnosticBuilder<'a, Noted> {
         self.parse_sess.create_note(note)
     }
+    #[track_caller]
     pub fn emit_note<'a>(&'a self, note: impl IntoDiagnostic<'a, Noted>) -> Noted {
         self.parse_sess.emit_note(note)
     }
+    #[track_caller]
     pub fn create_fatal<'a>(
         &'a self,
         fatal: impl IntoDiagnostic<'a, !>,
     ) -> DiagnosticBuilder<'a, !> {
         self.parse_sess.create_fatal(fatal)
     }
+    #[track_caller]
     pub fn emit_fatal<'a>(&'a self, fatal: impl IntoDiagnostic<'a, !>) -> ! {
         self.parse_sess.emit_fatal(fatal)
     }
@@ -541,6 +567,7 @@ impl Session {
     }
     #[allow(rustc::untranslatable_diagnostic)]
     #[allow(rustc::diagnostic_outside_of_impl)]
+    #[track_caller]
     pub fn span_warn<S: Into<MultiSpan>>(&self, sp: S, msg: impl Into<DiagnosticMessage>) {
         self.diagnostic().span_warn(sp, msg)
     }
@@ -587,6 +614,8 @@ impl Session {
     pub fn note_without_error(&self, msg: impl Into<DiagnosticMessage>) {
         self.diagnostic().note_without_error(msg)
     }
+
+    #[track_caller]
     pub fn span_note_without_error<S: Into<MultiSpan>>(
         &self,
         sp: S,
@@ -989,11 +1018,8 @@ impl Session {
                 return config::Lto::Fat;
             }
             config::LtoCli::Thin => {
-                return if self.opts.cli_forced_thinlto_off {
-                    config::Lto::Fat
-                } else {
-                    config::Lto::Thin
-                };
+                // The user explicitly asked for ThinLTO
+                return config::Lto::Thin;
             }
         }
 
@@ -1005,7 +1031,7 @@ impl Session {
 
         // If processing command line options determined that we're incompatible
         // with ThinLTO (e.g., `-C lto --emit llvm-ir`) then return that option.
-        if self.opts.cli_forced_thinlto_off {
+        if self.opts.cli_forced_local_thinlto_off {
             return config::Lto::No;
         }
 
@@ -1213,6 +1239,7 @@ fn default_emitter(
     fallback_bundle: LazyFallbackBundle,
 ) -> Box<dyn Emitter + sync::Send> {
     let macro_backtrace = sopts.unstable_opts.macro_backtrace;
+    let track_diagnostics = sopts.unstable_opts.track_diagnostics;
     match sopts.error_format {
         config::ErrorOutputType::HumanReadable(kind) => {
             let (short, color_config) = kind.unzip();
@@ -1236,6 +1263,7 @@ fn default_emitter(
                     sopts.unstable_opts.teach,
                     sopts.diagnostic_width,
                     macro_backtrace,
+                    track_diagnostics,
                 );
                 Box::new(emitter.ui_testing(sopts.unstable_opts.ui_testing))
             }
@@ -1250,6 +1278,7 @@ fn default_emitter(
                 json_rendered,
                 sopts.diagnostic_width,
                 macro_backtrace,
+                track_diagnostics,
             )
             .ui_testing(sopts.unstable_opts.ui_testing),
         ),
@@ -1280,7 +1309,7 @@ pub fn build_session(
 
     let sysroot = match &sopts.maybe_sysroot {
         Some(sysroot) => sysroot.clone(),
-        None => filesearch::get_or_default_sysroot(),
+        None => filesearch::get_or_default_sysroot().expect("Failed finding sysroot"),
     };
 
     let target_cfg = config::build_target_config(&sopts, target_override, &sysroot);
@@ -1552,11 +1581,18 @@ fn early_error_handler(output: config::ErrorOutputType) -> rustc_errors::Handler
                 false,
                 None,
                 false,
+                false,
             ))
         }
-        config::ErrorOutputType::Json { pretty, json_rendered } => {
-            Box::new(JsonEmitter::basic(pretty, json_rendered, None, fallback_bundle, None, false))
-        }
+        config::ErrorOutputType::Json { pretty, json_rendered } => Box::new(JsonEmitter::basic(
+            pretty,
+            json_rendered,
+            None,
+            fallback_bundle,
+            None,
+            false,
+            false,
+        )),
     };
     rustc_errors::Handler::with_emitter(true, None, emitter)
 }
diff --git a/compiler/rustc_span/src/lib.rs b/compiler/rustc_span/src/lib.rs
index 842aa98bc9ef..322c7104be42 100644
--- a/compiler/rustc_span/src/lib.rs
+++ b/compiler/rustc_span/src/lib.rs
@@ -558,7 +558,7 @@ impl Span {
         self.data_untracked().is_dummy()
     }
 
-    /// Returns `true` if this span comes from a macro or desugaring.
+    /// Returns `true` if this span comes from any kind of macro, desugaring or inlining.
     #[inline]
     pub fn from_expansion(self) -> bool {
         self.ctxt() != SyntaxContext::root()
@@ -571,6 +571,12 @@ impl Span {
         matches!(outer_expn.kind, ExpnKind::Macro(..)) && outer_expn.collapse_debuginfo
     }
 
+    /// Returns `true` if this span comes from MIR inlining.
+    pub fn is_inlined(self) -> bool {
+        let outer_expn = self.ctxt().outer_expn_data();
+        matches!(outer_expn.kind, ExpnKind::Inlined)
+    }
+
     /// Returns `true` if `span` originates in a derive-macro's expansion.
     pub fn in_derive_expansion(self) -> bool {
         matches!(self.ctxt().outer_expn_data().kind, ExpnKind::Macro(MacroKind::Derive, _))
diff --git a/compiler/rustc_span/src/source_map.rs b/compiler/rustc_span/src/source_map.rs
index f9566eeee946..7ea028b12efc 100644
--- a/compiler/rustc_span/src/source_map.rs
+++ b/compiler/rustc_span/src/source_map.rs
@@ -753,6 +753,50 @@ impl SourceMap {
         }
     }
 
+    /// Given a 'Span', tries to tell if the next character is '>'
+    /// and the previous charactoer is '<' after skipping white space
+    /// return true if wrapped by '<>'
+    pub fn span_wrapped_by_angle_bracket(&self, span: Span) -> bool {
+        self.span_to_source(span, |src, start_index, end_index| {
+            if src.get(start_index..end_index).is_none() {
+                return Ok(false);
+            }
+            // test the right side to match '>' after skipping white space
+            let end_src = &src[end_index..];
+            let mut i = 0;
+            while let Some(cc) = end_src.chars().nth(i) {
+                if cc == ' ' {
+                    i = i + 1;
+                } else if cc == '>' {
+                    // found > in the right;
+                    break;
+                } else {
+                    // failed to find '>' return false immediately
+                    return Ok(false);
+                }
+            }
+            // test the left side to match '<' after skipping white space
+            i = start_index;
+            let start_src = &src[0..start_index];
+            while let Some(cc) = start_src.chars().nth(i) {
+                if cc == ' ' {
+                    if i == 0 {
+                        return Ok(false);
+                    }
+                    i = i - 1;
+                } else if cc == '<' {
+                    // found < in the left
+                    break;
+                } else {
+                    // failed to find '<' return false immediately
+                    return Ok(false);
+                }
+            }
+            return Ok(true);
+        })
+        .map_or(false, |is_accessible| is_accessible)
+    }
+
     /// Given a `Span`, tries to get a shorter span ending just after the first occurrence of `char`
     /// `c`.
     pub fn span_through_char(&self, sp: Span, c: char) -> Span {
@@ -855,7 +899,8 @@ impl SourceMap {
     /// Returns a new span representing the next character after the end-point of this span.
     /// Special cases:
     /// - if span is a dummy one, returns the same span
-    /// - if next_point reached the end of source, return span with lo = hi
+    /// - if next_point reached the end of source, return a span exceeding the end of source,
+    ///   which means sm.span_to_snippet(next_point) will get `Err`
     /// - respect multi-byte characters
     pub fn next_point(&self, sp: Span) -> Span {
         if sp.is_dummy() {
@@ -864,9 +909,6 @@ impl SourceMap {
         let start_of_next_point = sp.hi().0;
 
         let width = self.find_width_of_character_at_span(sp, true);
-        if width == 0 {
-            return Span::new(sp.hi(), sp.hi(), sp.ctxt(), None);
-        }
         // If the width is 1, then the next span should only contain the next char besides current ending.
         // However, in the case of a multibyte character, where the width != 1, the next span should
         // span multiple bytes to include the whole character.
@@ -938,7 +980,7 @@ impl SourceMap {
         // Ensure indexes are also not malformed.
         if start_index > end_index || end_index > source_len - 1 {
             debug!("find_width_of_character_at_span: source indexes are malformed");
-            return 0;
+            return 1;
         }
 
         let src = local_begin.sf.external_src.borrow();
diff --git a/compiler/rustc_span/src/source_map/tests.rs b/compiler/rustc_span/src/source_map/tests.rs
index 1fd81018fa05..3cab59e8dbe6 100644
--- a/compiler/rustc_span/src/source_map/tests.rs
+++ b/compiler/rustc_span/src/source_map/tests.rs
@@ -511,16 +511,17 @@ fn test_next_point() {
     assert_eq!(span.lo().0, 4);
     assert_eq!(span.hi().0, 5);
 
-    // A non-empty span at the last byte should advance to create an empty
-    // span pointing at the end of the file.
+    // Reaching to the end of file, return a span that will get error with `span_to_snippet`
     let span = Span::with_root_ctxt(BytePos(4), BytePos(5));
     let span = sm.next_point(span);
     assert_eq!(span.lo().0, 5);
-    assert_eq!(span.hi().0, 5);
+    assert_eq!(span.hi().0, 6);
+    assert!(sm.span_to_snippet(span).is_err());
 
-    // Empty span pointing just past the last byte.
+    // Reaching to the end of file, return a span that will get error with `span_to_snippet`
     let span = Span::with_root_ctxt(BytePos(5), BytePos(5));
     let span = sm.next_point(span);
     assert_eq!(span.lo().0, 5);
-    assert_eq!(span.hi().0, 5);
+    assert_eq!(span.hi().0, 6);
+    assert!(sm.span_to_snippet(span).is_err());
 }
diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs
index 3fe79370c374..a56450a3573d 100644
--- a/compiler/rustc_span/src/symbol.rs
+++ b/compiler/rustc_span/src/symbol.rs
@@ -170,8 +170,6 @@ symbols! {
         Count,
         Cow,
         Debug,
-        DebugStruct,
-        DebugTuple,
         Decodable,
         Decoder,
         DecorateLint,
@@ -190,9 +188,6 @@ symbols! {
         Error,
         File,
         FileType,
-        Fn,
-        FnMut,
-        FnOnce,
         FormatSpec,
         Formatter,
         From,
@@ -211,7 +206,6 @@ symbols! {
         Input,
         Into,
         IntoDiagnostic,
-        IntoFuture,
         IntoIterator,
         IoRead,
         IoWrite,
@@ -256,7 +250,6 @@ symbols! {
         Pointer,
         Poll,
         ProcMacro,
-        ProcMacroHack,
         ProceduralMasqueradeDummyType,
         Range,
         RangeFrom,
@@ -332,7 +325,6 @@ symbols! {
         abi_vectorcall,
         abi_x86_interrupt,
         abort,
-        aborts,
         add,
         add_assign,
         add_with_overflow,
@@ -344,7 +336,6 @@ symbols! {
         align,
         align_offset,
         alignment,
-        alignstack,
         all,
         alloc,
         alloc_error_handler,
@@ -433,7 +424,6 @@ symbols! {
         bool,
         borrowck_graphviz_format,
         borrowck_graphviz_postflow,
-        borrowck_graphviz_preflow,
         box_free,
         box_patterns,
         box_syntax,
@@ -462,7 +452,6 @@ symbols! {
         cfg_doctest,
         cfg_eval,
         cfg_hide,
-        cfg_macro,
         cfg_panic,
         cfg_sanitize,
         cfg_target_abi,
@@ -470,7 +459,6 @@ symbols! {
         cfg_target_feature,
         cfg_target_has_atomic,
         cfg_target_has_atomic_equal_alignment,
-        cfg_target_has_atomic_load_store,
         cfg_target_thread_local,
         cfg_target_vendor,
         cfg_version,
@@ -495,19 +483,15 @@ symbols! {
         cold,
         collapse_debuginfo,
         column,
-        column_macro,
-        compare_and_swap,
         compare_exchange,
         compare_exchange_weak,
         compile_error,
-        compile_error_macro,
         compiler,
         compiler_builtins,
         compiler_fence,
         concat,
         concat_bytes,
         concat_idents,
-        concat_macro,
         conservative_impl_trait,
         console,
         const_allocate,
@@ -528,7 +512,6 @@ symbols! {
         const_fn_unsize,
         const_for,
         const_format_args,
-        const_generic_defaults,
         const_generics,
         const_generics_defaults,
         const_if_match,
@@ -547,22 +530,19 @@ symbols! {
         const_trait,
         const_trait_bound_opt_out,
         const_trait_impl,
-        const_transmute,
         const_try,
         constant,
         constructor,
-        contents,
         context,
-        convert,
         copy,
         copy_closures,
         copy_nonoverlapping,
         copysignf32,
         copysignf64,
         core,
-        core_intrinsics,
         core_panic,
         core_panic_2015_macro,
+        core_panic_2021_macro,
         core_panic_macro,
         cosf32,
         cosf64,
@@ -584,6 +564,7 @@ symbols! {
         custom_attribute,
         custom_derive,
         custom_inner_attributes,
+        custom_mir,
         custom_test_frameworks,
         d,
         d32,
@@ -597,7 +578,6 @@ symbols! {
         debug_assertions,
         debug_struct,
         debug_struct_fields_finish,
-        debug_trait_builder,
         debug_tuple,
         debug_tuple_fields_finish,
         debugger_visualizer,
@@ -619,6 +599,7 @@ symbols! {
         deref_mut,
         deref_target,
         derive,
+        derive_const,
         derive_default_enum,
         destruct,
         destructuring_assignment,
@@ -628,7 +609,6 @@ symbols! {
         discriminant_type,
         discriminant_value,
         dispatch_from_dyn,
-        display_trait,
         div,
         div_assign,
         doc,
@@ -659,7 +639,6 @@ symbols! {
         dyn_star,
         dyn_trait,
         e,
-        edition_macro_pats,
         edition_panic,
         eh_catch_typeinfo,
         eh_personality,
@@ -672,7 +651,6 @@ symbols! {
         encode,
         end,
         env,
-        env_macro,
         eprint_macro,
         eprintln_macro,
         eq,
@@ -694,6 +672,7 @@ symbols! {
         export_name,
         expr,
         extended_key_value_attributes,
+        extended_varargs_abi_support,
         extern_absolute_paths,
         extern_crate_item_prelude,
         extern_crate_self,
@@ -721,9 +700,7 @@ symbols! {
         field,
         field_init_shorthand,
         file,
-        file_macro,
         fill,
-        finish,
         flags,
         float,
         float_to_int_unchecked,
@@ -732,8 +709,6 @@ symbols! {
         fmaf32,
         fmaf64,
         fmt,
-        fmt_as_str,
-        fmt_internals,
         fmul_fast,
         fn_align,
         fn_must_use,
@@ -748,7 +723,6 @@ symbols! {
         format_args_macro,
         format_args_nl,
         format_macro,
-        fp,
         freeze,
         freg,
         frem_fast,
@@ -811,8 +785,8 @@ symbols! {
         ignore,
         impl_header_lifetime_elision,
         impl_lint_pass,
-        impl_macros,
         impl_trait_in_bindings,
+        impl_trait_in_fn_trait_return,
         implied_by,
         import,
         import_name_type,
@@ -822,7 +796,6 @@ symbols! {
         include,
         include_bytes,
         include_bytes_macro,
-        include_macro,
         include_str,
         include_str_macro,
         inclusive_range_syntax,
@@ -840,7 +813,6 @@ symbols! {
         instruction_set,
         integer_: "integer",
         integral,
-        intel,
         into_future,
         into_iter,
         intra_doc_pointers,
@@ -877,7 +849,6 @@ symbols! {
         lifetimes,
         likely,
         line,
-        line_macro,
         link,
         link_args,
         link_cfg,
@@ -922,7 +893,6 @@ symbols! {
         masked,
         match_beginning_vert,
         match_default_bindings,
-        matches_macro,
         maxnumf32,
         maxnumf64,
         may_dangle,
@@ -961,7 +931,6 @@ symbols! {
         modifiers,
         module,
         module_path,
-        module_path_macro,
         more_qualified_paths,
         more_struct_aliases,
         movbe_target_feature,
@@ -1031,7 +1000,6 @@ symbols! {
         non_exhaustive,
         non_exhaustive_omitted_patterns_lint,
         non_modrs_mods,
-        none_error,
         nontemporal_store,
         noop_method_borrow,
         noop_method_clone,
@@ -1056,7 +1024,6 @@ symbols! {
         optin_builtin_traits,
         option,
         option_env,
-        option_env_macro,
         options,
         or,
         or_patterns,
@@ -1099,7 +1066,6 @@ symbols! {
         plugins,
         pointee_trait,
         pointer,
-        pointer_trait_fmt,
         poll,
         position,
         post_dash_lto: "post-lto",
@@ -1126,7 +1092,6 @@ symbols! {
         proc_dash_macro: "proc-macro",
         proc_macro,
         proc_macro_attribute,
-        proc_macro_def_site,
         proc_macro_derive,
         proc_macro_expr,
         proc_macro_gen,
@@ -1227,9 +1192,6 @@ symbols! {
         rust_cold_cc,
         rust_eh_catch_typeinfo,
         rust_eh_personality,
-        rust_eh_register_frames,
-        rust_eh_unregister_frames,
-        rust_oom,
         rustc,
         rustc_allocator,
         rustc_allocator_zeroed,
@@ -1248,6 +1210,7 @@ symbols! {
         rustc_deallocator,
         rustc_def_path,
         rustc_default_body_unstable,
+        rustc_deny_explicit_impl,
         rustc_diagnostic_item,
         rustc_diagnostic_macros,
         rustc_dirty,
@@ -1302,7 +1265,6 @@ symbols! {
         rustc_serialize,
         rustc_skip_array_during_method_dispatch,
         rustc_specialization_trait,
-        rustc_stable,
         rustc_std_internal_symbol,
         rustc_strict_coherence,
         rustc_symbol_name,
@@ -1430,7 +1392,6 @@ symbols! {
         static_recursion,
         staticlib,
         std,
-        std_inject,
         std_panic,
         std_panic_2015_macro,
         std_panic_macro,
@@ -1445,7 +1406,6 @@ symbols! {
         str_trim_start,
         strict_provenance,
         stringify,
-        stringify_macro,
         struct_field_attributes,
         struct_inherit,
         struct_variant,
@@ -1473,10 +1433,8 @@ symbols! {
         target_has_atomic_load_store,
         target_os,
         target_pointer_width,
-        target_target_vendor,
         target_thread_local,
         target_vendor,
-        task,
         tbm_target_feature,
         termination,
         termination_trait,
@@ -1488,7 +1446,6 @@ symbols! {
         test_removed_feature,
         test_runner,
         test_unstable_lint,
-        then_with,
         thread,
         thread_local,
         thread_local_macro,
@@ -1520,7 +1477,6 @@ symbols! {
         try_trait_v2,
         tt,
         tuple,
-        tuple_from_req,
         tuple_indexing,
         tuple_trait,
         two_phase,
@@ -1564,7 +1520,6 @@ symbols! {
         unreachable_2015,
         unreachable_2015_macro,
         unreachable_2021,
-        unreachable_2021_macro,
         unreachable_code,
         unreachable_display,
         unreachable_macro,
@@ -1583,7 +1538,6 @@ symbols! {
                           from crates.io via `Cargo.toml` instead?",
         untagged_unions,
         unused_imports,
-        unused_qualifications,
         unwind,
         unwind_attributes,
         unwind_safe_trait,
@@ -1901,6 +1855,13 @@ impl fmt::Display for Symbol {
     }
 }
 
+// takes advantage of `str::to_string` specialization
+impl ToString for Symbol {
+    fn to_string(&self) -> String {
+        self.as_str().to_string()
+    }
+}
+
 impl<S: Encoder> Encodable<S> for Symbol {
     default fn encode(&self, s: &mut S) {
         s.emit_str(self.as_str());
diff --git a/compiler/rustc_symbol_mangling/src/test.rs b/compiler/rustc_symbol_mangling/src/test.rs
index c8c6fe2bf852..150459ce0f53 100644
--- a/compiler/rustc_symbol_mangling/src/test.rs
+++ b/compiler/rustc_symbol_mangling/src/test.rs
@@ -26,19 +26,19 @@ pub fn report_symbol_names(tcx: TyCtxt<'_>) {
         let crate_items = tcx.hir_crate_items(());
 
         for id in crate_items.items() {
-            symbol_names.process_attrs(id.def_id.def_id);
+            symbol_names.process_attrs(id.owner_id.def_id);
         }
 
         for id in crate_items.trait_items() {
-            symbol_names.process_attrs(id.def_id.def_id);
+            symbol_names.process_attrs(id.owner_id.def_id);
         }
 
         for id in crate_items.impl_items() {
-            symbol_names.process_attrs(id.def_id.def_id);
+            symbol_names.process_attrs(id.owner_id.def_id);
         }
 
         for id in crate_items.foreign_items() {
-            symbol_names.process_attrs(id.def_id.def_id);
+            symbol_names.process_attrs(id.owner_id.def_id);
         }
     })
 }
diff --git a/compiler/rustc_symbol_mangling/src/v0.rs b/compiler/rustc_symbol_mangling/src/v0.rs
index ecfe6861e84c..e540e2f2a219 100644
--- a/compiler/rustc_symbol_mangling/src/v0.rs
+++ b/compiler/rustc_symbol_mangling/src/v0.rs
@@ -218,7 +218,7 @@ impl<'tcx> SymbolMangler<'tcx> {
         let lifetimes = regions
             .into_iter()
             .map(|br| match br {
-                ty::BrAnon(i) => i,
+                ty::BrAnon(i, _) => i,
                 _ => bug!("symbol_names: non-anonymized region `{:?}` in `{:?}`", br, value),
             })
             .max()
@@ -335,7 +335,7 @@ impl<'tcx> Printer<'tcx> for &mut SymbolMangler<'tcx> {
 
             // Late-bound lifetimes use indices starting at 1,
             // see `BinderLevel` for more details.
-            ty::ReLateBound(debruijn, ty::BoundRegion { kind: ty::BrAnon(i), .. }) => {
+            ty::ReLateBound(debruijn, ty::BoundRegion { kind: ty::BrAnon(i, _), .. }) => {
                 let binder = &self.binders[self.binders.len() - 1 - debruijn.index()];
                 let depth = binder.lifetime_depths.start + i;
 
@@ -654,8 +654,7 @@ impl<'tcx> Printer<'tcx> for &mut SymbolMangler<'tcx> {
                             .builtin_deref(true)
                             .expect("tried to dereference on non-ptr type")
                             .ty;
-                        let dereferenced_const =
-                            self.tcx.mk_const(ty::ConstS { kind: ct.kind(), ty: pointee_ty });
+                        let dereferenced_const = self.tcx.mk_const(ct.kind(), pointee_ty);
                         self = dereferenced_const.print(self)?;
                     }
                 }
diff --git a/compiler/rustc_target/src/abi/call/loongarch.rs b/compiler/rustc_target/src/abi/call/loongarch.rs
new file mode 100644
index 000000000000..d29b479de5da
--- /dev/null
+++ b/compiler/rustc_target/src/abi/call/loongarch.rs
@@ -0,0 +1,342 @@
+use crate::abi::call::{ArgAbi, ArgExtension, CastTarget, FnAbi, PassMode, Reg, RegKind, Uniform};
+use crate::abi::{self, Abi, FieldsShape, HasDataLayout, Size, TyAbiInterface, TyAndLayout};
+use crate::spec::HasTargetSpec;
+
+#[derive(Copy, Clone)]
+enum RegPassKind {
+    Float(Reg),
+    Integer(Reg),
+    Unknown,
+}
+
+#[derive(Copy, Clone)]
+enum FloatConv {
+    FloatPair(Reg, Reg),
+    Float(Reg),
+    MixedPair(Reg, Reg),
+}
+
+#[derive(Copy, Clone)]
+struct CannotUseFpConv;
+
+fn is_loongarch_aggregate<'a, Ty>(arg: &ArgAbi<'a, Ty>) -> bool {
+    match arg.layout.abi {
+        Abi::Vector { .. } => true,
+        _ => arg.layout.is_aggregate(),
+    }
+}
+
+fn should_use_fp_conv_helper<'a, Ty, C>(
+    cx: &C,
+    arg_layout: &TyAndLayout<'a, Ty>,
+    xlen: u64,
+    flen: u64,
+    field1_kind: &mut RegPassKind,
+    field2_kind: &mut RegPassKind,
+) -> Result<(), CannotUseFpConv>
+where
+    Ty: TyAbiInterface<'a, C> + Copy,
+{
+    match arg_layout.abi {
+        Abi::Scalar(scalar) => match scalar.primitive() {
+            abi::Int(..) | abi::Pointer => {
+                if arg_layout.size.bits() > xlen {
+                    return Err(CannotUseFpConv);
+                }
+                match (*field1_kind, *field2_kind) {
+                    (RegPassKind::Unknown, _) => {
+                        *field1_kind = RegPassKind::Integer(Reg {
+                            kind: RegKind::Integer,
+                            size: arg_layout.size,
+                        });
+                    }
+                    (RegPassKind::Float(_), RegPassKind::Unknown) => {
+                        *field2_kind = RegPassKind::Integer(Reg {
+                            kind: RegKind::Integer,
+                            size: arg_layout.size,
+                        });
+                    }
+                    _ => return Err(CannotUseFpConv),
+                }
+            }
+            abi::F32 | abi::F64 => {
+                if arg_layout.size.bits() > flen {
+                    return Err(CannotUseFpConv);
+                }
+                match (*field1_kind, *field2_kind) {
+                    (RegPassKind::Unknown, _) => {
+                        *field1_kind =
+                            RegPassKind::Float(Reg { kind: RegKind::Float, size: arg_layout.size });
+                    }
+                    (_, RegPassKind::Unknown) => {
+                        *field2_kind =
+                            RegPassKind::Float(Reg { kind: RegKind::Float, size: arg_layout.size });
+                    }
+                    _ => return Err(CannotUseFpConv),
+                }
+            }
+        },
+        Abi::Vector { .. } | Abi::Uninhabited => return Err(CannotUseFpConv),
+        Abi::ScalarPair(..) | Abi::Aggregate { .. } => match arg_layout.fields {
+            FieldsShape::Primitive => {
+                unreachable!("aggregates can't have `FieldsShape::Primitive`")
+            }
+            FieldsShape::Union(_) => {
+                if !arg_layout.is_zst() {
+                    return Err(CannotUseFpConv);
+                }
+            }
+            FieldsShape::Array { count, .. } => {
+                for _ in 0..count {
+                    let elem_layout = arg_layout.field(cx, 0);
+                    should_use_fp_conv_helper(
+                        cx,
+                        &elem_layout,
+                        xlen,
+                        flen,
+                        field1_kind,
+                        field2_kind,
+                    )?;
+                }
+            }
+            FieldsShape::Arbitrary { .. } => {
+                match arg_layout.variants {
+                    abi::Variants::Multiple { .. } => return Err(CannotUseFpConv),
+                    abi::Variants::Single { .. } => (),
+                }
+                for i in arg_layout.fields.index_by_increasing_offset() {
+                    let field = arg_layout.field(cx, i);
+                    should_use_fp_conv_helper(cx, &field, xlen, flen, field1_kind, field2_kind)?;
+                }
+            }
+        },
+    }
+    Ok(())
+}
+
+fn should_use_fp_conv<'a, Ty, C>(
+    cx: &C,
+    arg: &TyAndLayout<'a, Ty>,
+    xlen: u64,
+    flen: u64,
+) -> Option<FloatConv>
+where
+    Ty: TyAbiInterface<'a, C> + Copy,
+{
+    let mut field1_kind = RegPassKind::Unknown;
+    let mut field2_kind = RegPassKind::Unknown;
+    if should_use_fp_conv_helper(cx, arg, xlen, flen, &mut field1_kind, &mut field2_kind).is_err() {
+        return None;
+    }
+    match (field1_kind, field2_kind) {
+        (RegPassKind::Integer(l), RegPassKind::Float(r)) => Some(FloatConv::MixedPair(l, r)),
+        (RegPassKind::Float(l), RegPassKind::Integer(r)) => Some(FloatConv::MixedPair(l, r)),
+        (RegPassKind::Float(l), RegPassKind::Float(r)) => Some(FloatConv::FloatPair(l, r)),
+        (RegPassKind::Float(f), RegPassKind::Unknown) => Some(FloatConv::Float(f)),
+        _ => None,
+    }
+}
+
+fn classify_ret<'a, Ty, C>(cx: &C, arg: &mut ArgAbi<'a, Ty>, xlen: u64, flen: u64) -> bool
+where
+    Ty: TyAbiInterface<'a, C> + Copy,
+{
+    if let Some(conv) = should_use_fp_conv(cx, &arg.layout, xlen, flen) {
+        match conv {
+            FloatConv::Float(f) => {
+                arg.cast_to(f);
+            }
+            FloatConv::FloatPair(l, r) => {
+                arg.cast_to(CastTarget::pair(l, r));
+            }
+            FloatConv::MixedPair(l, r) => {
+                arg.cast_to(CastTarget::pair(l, r));
+            }
+        }
+        return false;
+    }
+
+    let total = arg.layout.size;
+
+    // "Scalars wider than 2✕XLEN are passed by reference and are replaced in
+    // the argument list with the address."
+    // "Aggregates larger than 2✕XLEN bits are passed by reference and are
+    // replaced in the argument list with the address, as are C++ aggregates
+    // with nontrivial copy constructors, destructors, or vtables."
+    if total.bits() > 2 * xlen {
+        // We rely on the LLVM backend lowering code to lower passing a scalar larger than 2*XLEN.
+        if is_loongarch_aggregate(arg) {
+            arg.make_indirect();
+        }
+        return true;
+    }
+
+    let xlen_reg = match xlen {
+        32 => Reg::i32(),
+        64 => Reg::i64(),
+        _ => unreachable!("Unsupported XLEN: {}", xlen),
+    };
+    if is_loongarch_aggregate(arg) {
+        if total.bits() <= xlen {
+            arg.cast_to(xlen_reg);
+        } else {
+            arg.cast_to(Uniform { unit: xlen_reg, total: Size::from_bits(xlen * 2) });
+        }
+        return false;
+    }
+
+    // "When passed in registers, scalars narrower than XLEN bits are widened
+    // according to the sign of their type up to 32 bits, then sign-extended to
+    // XLEN bits."
+    extend_integer_width(arg, xlen);
+    false
+}
+
+fn classify_arg<'a, Ty, C>(
+    cx: &C,
+    arg: &mut ArgAbi<'a, Ty>,
+    xlen: u64,
+    flen: u64,
+    is_vararg: bool,
+    avail_gprs: &mut u64,
+    avail_fprs: &mut u64,
+) where
+    Ty: TyAbiInterface<'a, C> + Copy,
+{
+    if !is_vararg {
+        match should_use_fp_conv(cx, &arg.layout, xlen, flen) {
+            Some(FloatConv::Float(f)) if *avail_fprs >= 1 => {
+                *avail_fprs -= 1;
+                arg.cast_to(f);
+                return;
+            }
+            Some(FloatConv::FloatPair(l, r)) if *avail_fprs >= 2 => {
+                *avail_fprs -= 2;
+                arg.cast_to(CastTarget::pair(l, r));
+                return;
+            }
+            Some(FloatConv::MixedPair(l, r)) if *avail_fprs >= 1 && *avail_gprs >= 1 => {
+                *avail_gprs -= 1;
+                *avail_fprs -= 1;
+                arg.cast_to(CastTarget::pair(l, r));
+                return;
+            }
+            _ => (),
+        }
+    }
+
+    let total = arg.layout.size;
+    let align = arg.layout.align.abi.bits();
+
+    // "Scalars wider than 2✕XLEN are passed by reference and are replaced in
+    // the argument list with the address."
+    // "Aggregates larger than 2✕XLEN bits are passed by reference and are
+    // replaced in the argument list with the address, as are C++ aggregates
+    // with nontrivial copy constructors, destructors, or vtables."
+    if total.bits() > 2 * xlen {
+        // We rely on the LLVM backend lowering code to lower passing a scalar larger than 2*XLEN.
+        if is_loongarch_aggregate(arg) {
+            arg.make_indirect();
+        }
+        if *avail_gprs >= 1 {
+            *avail_gprs -= 1;
+        }
+        return;
+    }
+
+    let double_xlen_reg = match xlen {
+        32 => Reg::i64(),
+        64 => Reg::i128(),
+        _ => unreachable!("Unsupported XLEN: {}", xlen),
+    };
+
+    let xlen_reg = match xlen {
+        32 => Reg::i32(),
+        64 => Reg::i64(),
+        _ => unreachable!("Unsupported XLEN: {}", xlen),
+    };
+
+    if total.bits() > xlen {
+        let align_regs = align > xlen;
+        if is_loongarch_aggregate(arg) {
+            arg.cast_to(Uniform {
+                unit: if align_regs { double_xlen_reg } else { xlen_reg },
+                total: Size::from_bits(xlen * 2),
+            });
+        }
+        if align_regs && is_vararg {
+            *avail_gprs -= *avail_gprs % 2;
+        }
+        if *avail_gprs >= 2 {
+            *avail_gprs -= 2;
+        } else {
+            *avail_gprs = 0;
+        }
+        return;
+    } else if is_loongarch_aggregate(arg) {
+        arg.cast_to(xlen_reg);
+        if *avail_gprs >= 1 {
+            *avail_gprs -= 1;
+        }
+        return;
+    }
+
+    // "When passed in registers, scalars narrower than XLEN bits are widened
+    // according to the sign of their type up to 32 bits, then sign-extended to
+    // XLEN bits."
+    if *avail_gprs >= 1 {
+        extend_integer_width(arg, xlen);
+        *avail_gprs -= 1;
+    }
+}
+
+fn extend_integer_width<'a, Ty>(arg: &mut ArgAbi<'a, Ty>, xlen: u64) {
+    if let Abi::Scalar(scalar) = arg.layout.abi {
+        if let abi::Int(i, _) = scalar.primitive() {
+            // 32-bit integers are always sign-extended
+            if i.size().bits() == 32 && xlen > 32 {
+                if let PassMode::Direct(ref mut attrs) = arg.mode {
+                    attrs.ext(ArgExtension::Sext);
+                    return;
+                }
+            }
+        }
+    }
+
+    arg.extend_integer_width_to(xlen);
+}
+
+pub fn compute_abi_info<'a, Ty, C>(cx: &C, fn_abi: &mut FnAbi<'a, Ty>)
+where
+    Ty: TyAbiInterface<'a, C> + Copy,
+    C: HasDataLayout + HasTargetSpec,
+{
+    let xlen = cx.data_layout().pointer_size.bits();
+    let flen = match &cx.target_spec().llvm_abiname[..] {
+        "ilp32f" | "lp64f" => 32,
+        "ilp32d" | "lp64d" => 64,
+        _ => 0,
+    };
+
+    let mut avail_gprs = 8;
+    let mut avail_fprs = 8;
+
+    if !fn_abi.ret.is_ignore() && classify_ret(cx, &mut fn_abi.ret, xlen, flen) {
+        avail_gprs -= 1;
+    }
+
+    for (i, arg) in fn_abi.args.iter_mut().enumerate() {
+        if arg.is_ignore() {
+            continue;
+        }
+        classify_arg(
+            cx,
+            arg,
+            xlen,
+            flen,
+            i >= fn_abi.fixed_count as usize,
+            &mut avail_gprs,
+            &mut avail_fprs,
+        );
+    }
+}
diff --git a/compiler/rustc_target/src/abi/call/mod.rs b/compiler/rustc_target/src/abi/call/mod.rs
index 9e5f0e4d158b..c5a6f9893b6f 100644
--- a/compiler/rustc_target/src/abi/call/mod.rs
+++ b/compiler/rustc_target/src/abi/call/mod.rs
@@ -10,6 +10,7 @@ mod arm;
 mod avr;
 mod bpf;
 mod hexagon;
+mod loongarch;
 mod m68k;
 mod mips;
 mod mips64;
@@ -696,6 +697,7 @@ impl<'a, Ty> FnAbi<'a, Ty> {
             "amdgpu" => amdgpu::compute_abi_info(cx, self),
             "arm" => arm::compute_abi_info(cx, self),
             "avr" => avr::compute_abi_info(self),
+            "loongarch64" => loongarch::compute_abi_info(cx, self),
             "m68k" => m68k::compute_abi_info(self),
             "mips" => mips::compute_abi_info(cx, self),
             "mips64" => mips64::compute_abi_info(cx, self),
diff --git a/compiler/rustc_target/src/abi/mod.rs b/compiler/rustc_target/src/abi/mod.rs
index 7171ca7bf895..decbefc2f7c6 100644
--- a/compiler/rustc_target/src/abi/mod.rs
+++ b/compiler/rustc_target/src/abi/mod.rs
@@ -1083,6 +1083,11 @@ impl Abi {
         }
     }
 
+    #[inline]
+    pub fn is_sized(&self) -> bool {
+        !self.is_unsized()
+    }
+
     /// Returns `true` if this is a single signed integer scalar
     #[inline]
     pub fn is_signed(&self) -> bool {
@@ -1490,6 +1495,11 @@ impl<'a, Ty> TyAndLayout<'a, Ty> {
         self.abi.is_unsized()
     }
 
+    #[inline]
+    pub fn is_sized(&self) -> bool {
+        self.abi.is_sized()
+    }
+
     /// Returns `true` if the type is a ZST and not unsized.
     pub fn is_zst(&self) -> bool {
         match self.abi {
diff --git a/compiler/rustc_target/src/spec/aarch64_apple_darwin.rs b/compiler/rustc_target/src/spec/aarch64_apple_darwin.rs
index 6d919a4c2ad2..0f6bbc323174 100644
--- a/compiler/rustc_target/src/spec/aarch64_apple_darwin.rs
+++ b/compiler/rustc_target/src/spec/aarch64_apple_darwin.rs
@@ -1,26 +1,25 @@
+use super::apple_base::{macos_link_env_remove, macos_llvm_target, opts, Arch};
 use crate::spec::{FramePointer, SanitizerSet, Target, TargetOptions};
 
 pub fn target() -> Target {
-    let arch = "arm64";
-    let mut base = super::apple_base::opts("macos", arch, "");
+    let arch = Arch::Arm64;
+    let mut base = opts("macos", arch);
     base.cpu = "apple-a14".into();
     base.max_atomic_width = Some(128);
 
     // FIXME: The leak sanitizer currently fails the tests, see #88132.
     base.supported_sanitizers = SanitizerSet::ADDRESS | SanitizerSet::CFI | SanitizerSet::THREAD;
 
-    base.link_env_remove.to_mut().extend(super::apple_base::macos_link_env_remove());
-
-    // Clang automatically chooses a more specific target based on
-    // MACOSX_DEPLOYMENT_TARGET.  To enable cross-language LTO to work
-    // correctly, we do too.
-    let llvm_target = super::apple_base::macos_llvm_target(arch);
+    base.link_env_remove.to_mut().extend(macos_link_env_remove());
 
     Target {
-        llvm_target: llvm_target.into(),
+        // Clang automatically chooses a more specific target based on
+        // MACOSX_DEPLOYMENT_TARGET.  To enable cross-language LTO to work
+        // correctly, we do too.
+        llvm_target: macos_llvm_target(arch).into(),
         pointer_width: 64,
         data_layout: "e-m:o-i64:64-i128:128-n32:64-S128".into(),
-        arch: "aarch64".into(),
+        arch: arch.target_arch(),
         options: TargetOptions {
             mcount: "\u{1}mcount".into(),
             frame_pointer: FramePointer::NonLeaf,
diff --git a/compiler/rustc_target/src/spec/aarch64_apple_ios.rs b/compiler/rustc_target/src/spec/aarch64_apple_ios.rs
index beb9042390b7..b5f9eb1259da 100644
--- a/compiler/rustc_target/src/spec/aarch64_apple_ios.rs
+++ b/compiler/rustc_target/src/spec/aarch64_apple_ios.rs
@@ -1,19 +1,17 @@
-use super::apple_sdk_base::{opts, Arch};
+use super::apple_base::{ios_llvm_target, opts, Arch};
 use crate::spec::{FramePointer, Target, TargetOptions};
 
 pub fn target() -> Target {
-    // Clang automatically chooses a more specific target based on
-    // IPHONEOS_DEPLOYMENT_TARGET.
-    // This is required for the target to pick the right
-    // MACH-O commands, so we do too.
-    let arch = "arm64";
-    let llvm_target = super::apple_base::ios_llvm_target(arch);
-
+    let arch = Arch::Arm64;
     Target {
-        llvm_target: llvm_target.into(),
+        // Clang automatically chooses a more specific target based on
+        // IPHONEOS_DEPLOYMENT_TARGET.
+        // This is required for the target to pick the right
+        // MACH-O commands, so we do too.
+        llvm_target: ios_llvm_target(arch).into(),
         pointer_width: 64,
         data_layout: "e-m:o-i64:64-i128:128-n32:64-S128".into(),
-        arch: "aarch64".into(),
+        arch: arch.target_arch(),
         options: TargetOptions {
             features: "+neon,+fp-armv8,+apple-a7".into(),
             max_atomic_width: Some(128),
@@ -30,7 +28,7 @@ pub fn target() -> Target {
                 darwinpcs\0\
                 -Os\0"
                 .into(),
-            ..opts("ios", Arch::Arm64)
+            ..opts("ios", arch)
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/aarch64_apple_ios_macabi.rs b/compiler/rustc_target/src/spec/aarch64_apple_ios_macabi.rs
index 2d2671549cf5..0009972cf425 100644
--- a/compiler/rustc_target/src/spec/aarch64_apple_ios_macabi.rs
+++ b/compiler/rustc_target/src/spec/aarch64_apple_ios_macabi.rs
@@ -1,17 +1,18 @@
-use super::apple_sdk_base::{opts, Arch};
+use super::apple_base::{opts, Arch};
 use crate::spec::{Cc, FramePointer, LinkerFlavor, Lld, Target, TargetOptions};
 
 pub fn target() -> Target {
     let llvm_target = "arm64-apple-ios14.0-macabi";
 
-    let mut base = opts("ios", Arch::Arm64_macabi);
+    let arch = Arch::Arm64_macabi;
+    let mut base = opts("ios", arch);
     base.add_pre_link_args(LinkerFlavor::Darwin(Cc::Yes, Lld::No), &["-target", llvm_target]);
 
     Target {
         llvm_target: llvm_target.into(),
         pointer_width: 64,
         data_layout: "e-m:o-i64:64-i128:128-n32:64-S128".into(),
-        arch: "aarch64".into(),
+        arch: arch.target_arch(),
         options: TargetOptions {
             features: "+neon,+fp-armv8,+apple-a12".into(),
             max_atomic_width: Some(128),
diff --git a/compiler/rustc_target/src/spec/aarch64_apple_ios_sim.rs b/compiler/rustc_target/src/spec/aarch64_apple_ios_sim.rs
index b4e135f66e94..3374755e2dd8 100644
--- a/compiler/rustc_target/src/spec/aarch64_apple_ios_sim.rs
+++ b/compiler/rustc_target/src/spec/aarch64_apple_ios_sim.rs
@@ -1,21 +1,17 @@
-use super::apple_sdk_base::{opts, Arch};
+use super::apple_base::{ios_sim_llvm_target, opts, Arch};
 use crate::spec::{FramePointer, Target, TargetOptions};
 
 pub fn target() -> Target {
-    let base = opts("ios", Arch::Arm64_sim);
-
-    // Clang automatically chooses a more specific target based on
-    // IPHONEOS_DEPLOYMENT_TARGET.
-    // This is required for the simulator target to pick the right
-    // MACH-O commands, so we do too.
-    let arch = "arm64";
-    let llvm_target = super::apple_base::ios_sim_llvm_target(arch);
-
+    let arch = Arch::Arm64_sim;
     Target {
-        llvm_target: llvm_target.into(),
+        // Clang automatically chooses a more specific target based on
+        // IPHONEOS_DEPLOYMENT_TARGET.
+        // This is required for the simulator target to pick the right
+        // MACH-O commands, so we do too.
+        llvm_target: ios_sim_llvm_target(arch).into(),
         pointer_width: 64,
         data_layout: "e-m:o-i64:64-i128:128-n32:64-S128".into(),
-        arch: "aarch64".into(),
+        arch: arch.target_arch(),
         options: TargetOptions {
             features: "+neon,+fp-armv8,+apple-a7".into(),
             max_atomic_width: Some(128),
@@ -32,7 +28,7 @@ pub fn target() -> Target {
                 darwinpcs\0\
                 -Os\0"
                 .into(),
-            ..base
+            ..opts("ios", arch)
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/aarch64_apple_tvos.rs b/compiler/rustc_target/src/spec/aarch64_apple_tvos.rs
index 2e31d16dc76c..bb7c39ff26bd 100644
--- a/compiler/rustc_target/src/spec/aarch64_apple_tvos.rs
+++ b/compiler/rustc_target/src/spec/aarch64_apple_tvos.rs
@@ -1,18 +1,19 @@
-use super::apple_sdk_base::{opts, Arch};
+use super::apple_base::{opts, Arch};
 use crate::spec::{FramePointer, Target, TargetOptions};
 
 pub fn target() -> Target {
+    let arch = Arch::Arm64;
     Target {
         llvm_target: "arm64-apple-tvos".into(),
         pointer_width: 64,
         data_layout: "e-m:o-i64:64-i128:128-n32:64-S128".into(),
-        arch: "aarch64".into(),
+        arch: arch.target_arch(),
         options: TargetOptions {
             features: "+neon,+fp-armv8,+apple-a7".into(),
             max_atomic_width: Some(128),
             forces_embed_bitcode: true,
             frame_pointer: FramePointer::NonLeaf,
-            ..opts("tvos", Arch::Arm64)
+            ..opts("tvos", arch)
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/aarch64_apple_watchos_sim.rs b/compiler/rustc_target/src/spec/aarch64_apple_watchos_sim.rs
index 3059f42140be..e4af4127c222 100644
--- a/compiler/rustc_target/src/spec/aarch64_apple_watchos_sim.rs
+++ b/compiler/rustc_target/src/spec/aarch64_apple_watchos_sim.rs
@@ -1,21 +1,17 @@
-use super::apple_sdk_base::{opts, Arch};
+use super::apple_base::{opts, watchos_sim_llvm_target, Arch};
 use crate::spec::{FramePointer, Target, TargetOptions};
 
 pub fn target() -> Target {
-    let base = opts("watchos", Arch::Arm64_sim);
-
-    // Clang automatically chooses a more specific target based on
-    // WATCHOS_DEPLOYMENT_TARGET.
-    // This is required for the simulator target to pick the right
-    // MACH-O commands, so we do too.
-    let arch = "arm64";
-    let llvm_target = super::apple_base::watchos_sim_llvm_target(arch);
-
+    let arch = Arch::Arm64_sim;
     Target {
-        llvm_target: llvm_target.into(),
+        // Clang automatically chooses a more specific target based on
+        // WATCHOS_DEPLOYMENT_TARGET.
+        // This is required for the simulator target to pick the right
+        // MACH-O commands, so we do too.
+        llvm_target: watchos_sim_llvm_target(arch).into(),
         pointer_width: 64,
         data_layout: "e-m:o-i64:64-i128:128-n32:64-S128".into(),
-        arch: "aarch64".into(),
+        arch: arch.target_arch(),
         options: TargetOptions {
             features: "+neon,+fp-armv8,+apple-a7".into(),
             max_atomic_width: Some(128),
@@ -32,7 +28,7 @@ pub fn target() -> Target {
                 darwinpcs\0\
                 -Os\0"
                 .into(),
-            ..base
+            ..opts("watchos", arch)
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/aarch64_unknown_nto_qnx_710.rs b/compiler/rustc_target/src/spec/aarch64_unknown_nto_qnx_710.rs
new file mode 100644
index 000000000000..916b6137b650
--- /dev/null
+++ b/compiler/rustc_target/src/spec/aarch64_unknown_nto_qnx_710.rs
@@ -0,0 +1,28 @@
+use super::nto_qnx_base;
+use crate::spec::{Cc, LinkerFlavor, Lld, Target, TargetOptions};
+
+pub fn target() -> Target {
+    Target {
+        llvm_target: "aarch64-unknown-unknown".into(),
+        pointer_width: 64,
+        // from: https://llvm.org/docs/LangRef.html#data-layout
+        // e         = little endian
+        // m:e       = ELF mangling: Private symbols get a .L prefix
+        // i8:8:32   = 8-bit-integer, minimum_alignment=8, preferred_alignment=32
+        // i16:16:32 = 16-bit-integer, minimum_alignment=16, preferred_alignment=32
+        // i64:64    = 64-bit-integer, minimum_alignment=64, preferred_alignment=64
+        // i128:128  = 128-bit-integer, minimum_alignment=128, preferred_alignment=128
+        // n32:64    = 32 and 64 are native integer widths; Elements of this set are considered to support most general arithmetic operations efficiently.
+        // S128      = 128 bits are the natural alignment of the stack in bits.
+        data_layout: "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128".into(),
+        arch: "aarch64".into(),
+        options: TargetOptions {
+            max_atomic_width: Some(128),
+            pre_link_args: TargetOptions::link_args(
+                LinkerFlavor::Gnu(Cc::Yes, Lld::No),
+                &["-Vgcc_ntoaarch64le_cxx"],
+            ),
+            ..nto_qnx_base::opts()
+        },
+    }
+}
diff --git a/compiler/rustc_target/src/spec/abi.rs b/compiler/rustc_target/src/spec/abi.rs
index ce45fa13970b..cb2a0c04c6aa 100644
--- a/compiler/rustc_target/src/spec/abi.rs
+++ b/compiler/rustc_target/src/spec/abi.rs
@@ -40,6 +40,28 @@ pub enum Abi {
     RustCold,
 }
 
+impl Abi {
+    pub fn supports_varargs(self) -> bool {
+        // * C and Cdecl obviously support varargs.
+        // * C can be based on SysV64 or Win64, so they must support varargs.
+        // * EfiApi is based on Win64 or C, so it also supports it.
+        //
+        // * Stdcall does not, because it would be impossible for the callee to clean
+        //   up the arguments. (callee doesn't know how many arguments are there)
+        // * Same for Fastcall, Vectorcall and Thiscall.
+        // * System can become Stdcall, so is also a no-no.
+        // * Other calling conventions are related to hardware or the compiler itself.
+        match self {
+            Self::C { .. }
+            | Self::Cdecl { .. }
+            | Self::Win64 { .. }
+            | Self::SysV64 { .. }
+            | Self::EfiApi => true,
+            _ => false,
+        }
+    }
+}
+
 #[derive(Copy, Clone)]
 pub struct AbiData {
     abi: Abi,
diff --git a/compiler/rustc_target/src/spec/apple/tests.rs b/compiler/rustc_target/src/spec/apple/tests.rs
new file mode 100644
index 000000000000..d062b36742d6
--- /dev/null
+++ b/compiler/rustc_target/src/spec/apple/tests.rs
@@ -0,0 +1,20 @@
+use crate::spec::{
+    aarch64_apple_ios_sim, aarch64_apple_watchos_sim, x86_64_apple_ios, x86_64_apple_tvos,
+    x86_64_apple_watchos_sim,
+};
+
+#[test]
+fn simulator_targets_set_abi() {
+    let all_sim_targets = [
+        x86_64_apple_ios::target(),
+        x86_64_apple_tvos::target(),
+        x86_64_apple_watchos_sim::target(),
+        aarch64_apple_ios_sim::target(),
+        // Note: There is currently no ARM64 tvOS simulator target
+        aarch64_apple_watchos_sim::target(),
+    ];
+
+    for target in all_sim_targets {
+        assert_eq!(target.abi, "sim")
+    }
+}
diff --git a/compiler/rustc_target/src/spec/apple_base.rs b/compiler/rustc_target/src/spec/apple_base.rs
index 40bc59ca145e..23c826cb1bda 100644
--- a/compiler/rustc_target/src/spec/apple_base.rs
+++ b/compiler/rustc_target/src/spec/apple_base.rs
@@ -3,7 +3,88 @@ use std::{borrow::Cow, env};
 use crate::spec::{cvs, Cc, DebuginfoKind, FramePointer, LinkArgs};
 use crate::spec::{LinkerFlavor, Lld, SplitDebuginfo, StaticCow, TargetOptions};
 
-fn pre_link_args(os: &'static str, arch: &'static str, abi: &'static str) -> LinkArgs {
+#[cfg(test)]
+#[path = "apple/tests.rs"]
+mod tests;
+
+use Arch::*;
+#[allow(non_camel_case_types)]
+#[derive(Copy, Clone)]
+pub enum Arch {
+    Armv7,
+    Armv7k,
+    Armv7s,
+    Arm64,
+    Arm64_32,
+    I386,
+    I686,
+    X86_64,
+    X86_64_sim,
+    X86_64_macabi,
+    Arm64_macabi,
+    Arm64_sim,
+}
+
+impl Arch {
+    pub fn target_name(self) -> &'static str {
+        match self {
+            Armv7 => "armv7",
+            Armv7k => "armv7k",
+            Armv7s => "armv7s",
+            Arm64 | Arm64_macabi | Arm64_sim => "arm64",
+            Arm64_32 => "arm64_32",
+            I386 => "i386",
+            I686 => "i686",
+            X86_64 | X86_64_sim | X86_64_macabi => "x86_64",
+        }
+    }
+
+    pub fn target_arch(self) -> Cow<'static, str> {
+        Cow::Borrowed(match self {
+            Armv7 | Armv7k | Armv7s => "arm",
+            Arm64 | Arm64_32 | Arm64_macabi | Arm64_sim => "aarch64",
+            I386 | I686 => "x86",
+            X86_64 | X86_64_sim | X86_64_macabi => "x86_64",
+        })
+    }
+
+    fn target_abi(self) -> &'static str {
+        match self {
+            Armv7 | Armv7k | Armv7s | Arm64 | Arm64_32 | I386 | I686 | X86_64 => "",
+            X86_64_macabi | Arm64_macabi => "macabi",
+            // x86_64-apple-ios is a simulator target, even though it isn't
+            // declared that way in the target like the other ones...
+            Arm64_sim | X86_64_sim => "sim",
+        }
+    }
+
+    fn target_cpu(self) -> &'static str {
+        match self {
+            Armv7 => "cortex-a8", // iOS7 is supported on iPhone 4 and higher
+            Armv7k => "cortex-a8",
+            Armv7s => "cortex-a9",
+            Arm64 => "apple-a7",
+            Arm64_32 => "apple-s4",
+            I386 | I686 => "yonah",
+            X86_64 | X86_64_sim => "core2",
+            X86_64_macabi => "core2",
+            Arm64_macabi => "apple-a12",
+            Arm64_sim => "apple-a12",
+        }
+    }
+
+    fn link_env_remove(self) -> StaticCow<[StaticCow<str>]> {
+        match self {
+            Armv7 | Armv7k | Armv7s | Arm64 | Arm64_32 | I386 | I686 | X86_64 | X86_64_sim
+            | Arm64_sim => {
+                cvs!["MACOSX_DEPLOYMENT_TARGET"]
+            }
+            X86_64_macabi | Arm64_macabi => cvs!["IPHONEOS_DEPLOYMENT_TARGET"],
+        }
+    }
+}
+
+fn pre_link_args(os: &'static str, arch: Arch, abi: &'static str) -> LinkArgs {
     let platform_name: StaticCow<str> = match abi {
         "sim" => format!("{}-simulator", os).into(),
         "macabi" => "mac-catalyst".into(),
@@ -19,6 +100,8 @@ fn pre_link_args(os: &'static str, arch: &'static str, abi: &'static str) -> Lin
     }
     .into();
 
+    let arch = arch.target_name();
+
     let mut args = TargetOptions::link_args(
         LinkerFlavor::Darwin(Cc::No, Lld::No),
         &["-arch", arch, "-platform_version"],
@@ -35,24 +118,29 @@ fn pre_link_args(os: &'static str, arch: &'static str, abi: &'static str) -> Lin
     args
 }
 
-pub fn opts(os: &'static str, arch: &'static str, abi: &'static str) -> TargetOptions {
-    // ELF TLS is only available in macOS 10.7+. If you try to compile for 10.6
+pub fn opts(os: &'static str, arch: Arch) -> TargetOptions {
+    // Static TLS is only available in macOS 10.7+. If you try to compile for 10.6
     // either the linker will complain if it is used or the binary will end up
     // segfaulting at runtime when run on 10.6. Rust by default supports macOS
     // 10.7+, but there is a standard environment variable,
     // MACOSX_DEPLOYMENT_TARGET, which is used to signal targeting older
     // versions of macOS. For example compiling on 10.10 with
     // MACOSX_DEPLOYMENT_TARGET set to 10.6 will cause the linker to generate
-    // warnings about the usage of ELF TLS.
+    // warnings about the usage of static TLS.
     //
-    // Here we detect what version is being requested, defaulting to 10.7. ELF
+    // Here we detect what version is being requested, defaulting to 10.7. Static
     // TLS is flagged as enabled if it looks to be supported. The architecture
     // only matters for default deployment target which is 11.0 for ARM64 and
     // 10.7 for everything else.
-    let has_thread_local = macos_deployment_target("x86_64") >= (10, 7);
+    let has_thread_local = os == "macos" && macos_deployment_target(Arch::X86_64) >= (10, 7);
+
+    let abi = arch.target_abi();
 
     TargetOptions {
+        abi: abi.into(),
         os: os.into(),
+        cpu: arch.target_cpu().into(),
+        link_env_remove: arch.link_env_remove(),
         vendor: "apple".into(),
         linker_flavor: LinkerFlavor::Darwin(Cc::Yes, Lld::No),
         // macOS has -dead_strip, which doesn't rely on function_sections
@@ -103,23 +191,24 @@ fn deployment_target(var_name: &str) -> Option<(u32, u32)> {
         .and_then(|(a, b)| a.parse::<u32>().and_then(|a| b.parse::<u32>().map(|b| (a, b))).ok())
 }
 
-fn macos_default_deployment_target(arch: &str) -> (u32, u32) {
-    if arch == "arm64" { (11, 0) } else { (10, 7) }
+fn macos_default_deployment_target(arch: Arch) -> (u32, u32) {
+    // Note: Arm64_sim is not included since macOS has no simulator.
+    if matches!(arch, Arm64 | Arm64_macabi) { (11, 0) } else { (10, 7) }
 }
 
-fn macos_deployment_target(arch: &str) -> (u32, u32) {
+fn macos_deployment_target(arch: Arch) -> (u32, u32) {
     deployment_target("MACOSX_DEPLOYMENT_TARGET")
         .unwrap_or_else(|| macos_default_deployment_target(arch))
 }
 
-fn macos_lld_platform_version(arch: &str) -> String {
+fn macos_lld_platform_version(arch: Arch) -> String {
     let (major, minor) = macos_deployment_target(arch);
     format!("{}.{}", major, minor)
 }
 
-pub fn macos_llvm_target(arch: &str) -> String {
+pub fn macos_llvm_target(arch: Arch) -> String {
     let (major, minor) = macos_deployment_target(arch);
-    format!("{}-apple-macosx{}.{}.0", arch, major, minor)
+    format!("{}-apple-macosx{}.{}.0", arch.target_name(), major, minor)
 }
 
 pub fn macos_link_env_remove() -> Vec<StaticCow<str>> {
@@ -142,7 +231,7 @@ fn ios_deployment_target() -> (u32, u32) {
     deployment_target("IPHONEOS_DEPLOYMENT_TARGET").unwrap_or((7, 0))
 }
 
-pub fn ios_llvm_target(arch: &str) -> String {
+pub fn ios_llvm_target(arch: Arch) -> String {
     // Modern iOS tooling extracts information about deployment target
     // from LC_BUILD_VERSION. This load command will only be emitted when
     // we build with a version specific `llvm_target`, with the version
@@ -150,7 +239,7 @@ pub fn ios_llvm_target(arch: &str) -> String {
     // to pick it up (since std and core are still built with the fallback
     // of version 7.0 and hence emit the old LC_IPHONE_MIN_VERSION).
     let (major, minor) = ios_deployment_target();
-    format!("{}-apple-ios{}.{}.0", arch, major, minor)
+    format!("{}-apple-ios{}.{}.0", arch.target_name(), major, minor)
 }
 
 fn ios_lld_platform_version() -> String {
@@ -158,9 +247,9 @@ fn ios_lld_platform_version() -> String {
     format!("{}.{}", major, minor)
 }
 
-pub fn ios_sim_llvm_target(arch: &str) -> String {
+pub fn ios_sim_llvm_target(arch: Arch) -> String {
     let (major, minor) = ios_deployment_target();
-    format!("{}-apple-ios{}.{}.0-simulator", arch, major, minor)
+    format!("{}-apple-ios{}.{}.0-simulator", arch.target_name(), major, minor)
 }
 
 fn tvos_deployment_target() -> (u32, u32) {
@@ -181,7 +270,7 @@ fn watchos_lld_platform_version() -> String {
     format!("{}.{}", major, minor)
 }
 
-pub fn watchos_sim_llvm_target(arch: &str) -> String {
+pub fn watchos_sim_llvm_target(arch: Arch) -> String {
     let (major, minor) = watchos_deployment_target();
-    format!("{}-apple-watchos{}.{}.0-simulator", arch, major, minor)
+    format!("{}-apple-watchos{}.{}.0-simulator", arch.target_name(), major, minor)
 }
diff --git a/compiler/rustc_target/src/spec/apple_sdk_base.rs b/compiler/rustc_target/src/spec/apple_sdk_base.rs
deleted file mode 100644
index 49e302676a7b..000000000000
--- a/compiler/rustc_target/src/spec/apple_sdk_base.rs
+++ /dev/null
@@ -1,72 +0,0 @@
-use crate::spec::{cvs, TargetOptions};
-use std::borrow::Cow;
-
-use Arch::*;
-#[allow(non_camel_case_types)]
-#[derive(Copy, Clone)]
-pub enum Arch {
-    Armv7,
-    Armv7k,
-    Armv7s,
-    Arm64,
-    Arm64_32,
-    I386,
-    X86_64,
-    X86_64_macabi,
-    Arm64_macabi,
-    Arm64_sim,
-}
-
-fn target_arch_name(arch: Arch) -> &'static str {
-    match arch {
-        Armv7 => "armv7",
-        Armv7k => "armv7k",
-        Armv7s => "armv7s",
-        Arm64 | Arm64_macabi | Arm64_sim => "arm64",
-        Arm64_32 => "arm64_32",
-        I386 => "i386",
-        X86_64 | X86_64_macabi => "x86_64",
-    }
-}
-
-fn target_abi(arch: Arch) -> &'static str {
-    match arch {
-        Armv7 | Armv7k | Armv7s | Arm64 | Arm64_32 | I386 | X86_64 => "",
-        X86_64_macabi | Arm64_macabi => "macabi",
-        Arm64_sim => "sim",
-    }
-}
-
-fn target_cpu(arch: Arch) -> &'static str {
-    match arch {
-        Armv7 => "cortex-a8", // iOS7 is supported on iPhone 4 and higher
-        Armv7k => "cortex-a8",
-        Armv7s => "cortex-a9",
-        Arm64 => "apple-a7",
-        Arm64_32 => "apple-s4",
-        I386 => "yonah",
-        X86_64 => "core2",
-        X86_64_macabi => "core2",
-        Arm64_macabi => "apple-a12",
-        Arm64_sim => "apple-a12",
-    }
-}
-
-fn link_env_remove(arch: Arch) -> Cow<'static, [Cow<'static, str>]> {
-    match arch {
-        Armv7 | Armv7k | Armv7s | Arm64 | Arm64_32 | I386 | X86_64 | Arm64_sim => {
-            cvs!["MACOSX_DEPLOYMENT_TARGET"]
-        }
-        X86_64_macabi | Arm64_macabi => cvs!["IPHONEOS_DEPLOYMENT_TARGET"],
-    }
-}
-
-pub fn opts(os: &'static str, arch: Arch) -> TargetOptions {
-    TargetOptions {
-        abi: target_abi(arch).into(),
-        cpu: target_cpu(arch).into(),
-        link_env_remove: link_env_remove(arch),
-        has_thread_local: false,
-        ..super::apple_base::opts(os, target_arch_name(arch), target_abi(arch))
-    }
-}
diff --git a/compiler/rustc_target/src/spec/arm64_32_apple_watchos.rs b/compiler/rustc_target/src/spec/arm64_32_apple_watchos.rs
index cb7f5f2a5830..2cf2cbc75100 100644
--- a/compiler/rustc_target/src/spec/arm64_32_apple_watchos.rs
+++ b/compiler/rustc_target/src/spec/arm64_32_apple_watchos.rs
@@ -1,4 +1,4 @@
-use super::apple_sdk_base::{opts, Arch};
+use super::apple_base::{opts, Arch};
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
diff --git a/compiler/rustc_target/src/spec/armv7_apple_ios.rs b/compiler/rustc_target/src/spec/armv7_apple_ios.rs
index 57fd74a36b65..3259c854791c 100644
--- a/compiler/rustc_target/src/spec/armv7_apple_ios.rs
+++ b/compiler/rustc_target/src/spec/armv7_apple_ios.rs
@@ -1,18 +1,21 @@
-use super::apple_sdk_base::{opts, Arch};
+use super::apple_base::{ios_llvm_target, opts, Arch};
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
-    let llvm_target = super::apple_base::ios_llvm_target("armv7");
-
+    let arch = Arch::Armv7;
     Target {
-        llvm_target: llvm_target.into(),
+        // Clang automatically chooses a more specific target based on
+        // IPHONEOS_DEPLOYMENT_TARGET.
+        // This is required for the target to pick the right
+        // MACH-O commands, so we do too.
+        llvm_target: ios_llvm_target(arch).into(),
         pointer_width: 32,
         data_layout: "e-m:o-p:32:32-Fi8-f64:32:64-v64:32:64-v128:32:128-a:0:32-n32-S32".into(),
-        arch: "arm".into(),
+        arch: arch.target_arch(),
         options: TargetOptions {
             features: "+v7,+vfp3,+neon".into(),
             max_atomic_width: Some(64),
-            ..opts("ios", Arch::Armv7)
+            ..opts("ios", arch)
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/armv7k_apple_watchos.rs b/compiler/rustc_target/src/spec/armv7k_apple_watchos.rs
index af5d1c2ff458..45ead8d65aba 100644
--- a/compiler/rustc_target/src/spec/armv7k_apple_watchos.rs
+++ b/compiler/rustc_target/src/spec/armv7k_apple_watchos.rs
@@ -1,13 +1,13 @@
-use super::apple_sdk_base::{opts, Arch};
+use super::apple_base::{opts, Arch};
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
-    let base = opts("watchos", Arch::Armv7k);
+    let arch = Arch::Armv7k;
     Target {
         llvm_target: "armv7k-apple-watchos".into(),
         pointer_width: 32,
         data_layout: "e-m:o-p:32:32-Fi8-i64:64-a:0:32-n32-S128".into(),
-        arch: "arm".into(),
+        arch: arch.target_arch(),
         options: TargetOptions {
             features: "+v7,+vfp4,+neon".into(),
             max_atomic_width: Some(64),
@@ -22,7 +22,7 @@ pub fn target() -> Target {
                 darwinpcs\0\
                 -Os\0"
                 .into(),
-            ..base
+            ..opts("watchos", arch)
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/armv7s_apple_ios.rs b/compiler/rustc_target/src/spec/armv7s_apple_ios.rs
index cc17265b2b8d..be4bc6758443 100644
--- a/compiler/rustc_target/src/spec/armv7s_apple_ios.rs
+++ b/compiler/rustc_target/src/spec/armv7s_apple_ios.rs
@@ -1,16 +1,17 @@
-use super::apple_sdk_base::{opts, Arch};
+use super::apple_base::{opts, Arch};
 use crate::spec::{Target, TargetOptions};
 
 pub fn target() -> Target {
+    let arch = Arch::Armv7s;
     Target {
         llvm_target: "armv7s-apple-ios".into(),
         pointer_width: 32,
         data_layout: "e-m:o-p:32:32-Fi8-f64:32:64-v64:32:64-v128:32:128-a:0:32-n32-S32".into(),
-        arch: "arm".into(),
+        arch: arch.target_arch(),
         options: TargetOptions {
             features: "+v7,+vfp4,+neon".into(),
             max_atomic_width: Some(64),
-            ..opts("ios", Arch::Armv7s)
+            ..opts("ios", arch)
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/i386_apple_ios.rs b/compiler/rustc_target/src/spec/i386_apple_ios.rs
index b85214a9c6b4..5819981612e8 100644
--- a/compiler/rustc_target/src/spec/i386_apple_ios.rs
+++ b/compiler/rustc_target/src/spec/i386_apple_ios.rs
@@ -1,21 +1,23 @@
-use super::apple_sdk_base::{opts, Arch};
+use super::apple_base::{ios_sim_llvm_target, opts, Arch};
 use crate::spec::{StackProbeType, Target, TargetOptions};
 
 pub fn target() -> Target {
-    let base = opts("ios", Arch::I386);
-    let llvm_target = super::apple_base::ios_sim_llvm_target("i386");
-
+    let arch = Arch::I386;
     Target {
-        llvm_target: llvm_target.into(),
+        // Clang automatically chooses a more specific target based on
+        // IPHONEOS_DEPLOYMENT_TARGET.
+        // This is required for the target to pick the right
+        // MACH-O commands, so we do too.
+        llvm_target: ios_sim_llvm_target(arch).into(),
         pointer_width: 32,
         data_layout: "e-m:o-p:32:32-p270:32:32-p271:32:32-p272:64:64-\
             f64:32:64-f80:128-n8:16:32-S128"
             .into(),
-        arch: "x86".into(),
+        arch: arch.target_arch(),
         options: TargetOptions {
             max_atomic_width: Some(64),
             stack_probes: StackProbeType::X86,
-            ..base
+            ..opts("ios", arch)
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/i686_apple_darwin.rs b/compiler/rustc_target/src/spec/i686_apple_darwin.rs
index 15607c12ea90..8b968af5eccf 100644
--- a/compiler/rustc_target/src/spec/i686_apple_darwin.rs
+++ b/compiler/rustc_target/src/spec/i686_apple_darwin.rs
@@ -1,28 +1,28 @@
+use super::apple_base::{macos_link_env_remove, macos_llvm_target, opts, Arch};
 use crate::spec::{Cc, FramePointer, LinkerFlavor, Lld, StackProbeType, Target, TargetOptions};
 
 pub fn target() -> Target {
-    // ld64 only understand i386 and not i686
-    let mut base = super::apple_base::opts("macos", "i386", "");
-    base.cpu = "yonah".into();
+    // ld64 only understands i386 and not i686
+    let arch = Arch::I386;
+    let mut base = opts("macos", arch);
     base.max_atomic_width = Some(64);
     base.add_pre_link_args(LinkerFlavor::Darwin(Cc::Yes, Lld::No), &["-m32"]);
-    base.link_env_remove.to_mut().extend(super::apple_base::macos_link_env_remove());
+    base.link_env_remove.to_mut().extend(macos_link_env_remove());
     base.stack_probes = StackProbeType::X86;
     base.frame_pointer = FramePointer::Always;
 
-    // Clang automatically chooses a more specific target based on
-    // MACOSX_DEPLOYMENT_TARGET.  To enable cross-language LTO to work
-    // correctly, we do too.
-    let arch = "i686";
-    let llvm_target = super::apple_base::macos_llvm_target(&arch);
-
     Target {
-        llvm_target: llvm_target.into(),
+        // Clang automatically chooses a more specific target based on
+        // MACOSX_DEPLOYMENT_TARGET.  To enable cross-language LTO to work
+        // correctly, we do too.
+        //
+        // While ld64 doesn't understand i686, LLVM does.
+        llvm_target: macos_llvm_target(Arch::I686).into(),
         pointer_width: 32,
         data_layout: "e-m:o-p:32:32-p270:32:32-p271:32:32-p272:64:64-\
             f64:32:64-f80:128-n8:16:32-S128"
             .into(),
-        arch: "x86".into(),
+        arch: arch.target_arch(),
         options: TargetOptions { mcount: "\u{1}mcount".into(), ..base },
     }
 }
diff --git a/compiler/rustc_target/src/spec/linux_kernel_base.rs b/compiler/rustc_target/src/spec/linux_kernel_base.rs
deleted file mode 100644
index f41533a9548f..000000000000
--- a/compiler/rustc_target/src/spec/linux_kernel_base.rs
+++ /dev/null
@@ -1,18 +0,0 @@
-use crate::spec::TargetOptions;
-use crate::spec::{FramePointer, PanicStrategy, RelocModel, RelroLevel, StackProbeType};
-
-pub fn opts() -> TargetOptions {
-    TargetOptions {
-        env: "gnu".into(),
-        disable_redzone: true,
-        panic_strategy: PanicStrategy::Abort,
-        stack_probes: StackProbeType::X86,
-        frame_pointer: FramePointer::Always,
-        position_independent_executables: true,
-        needs_plt: true,
-        relro_level: RelroLevel::Full,
-        relocation_model: RelocModel::Static,
-
-        ..Default::default()
-    }
-}
diff --git a/compiler/rustc_target/src/spec/mipsel_sony_psx.rs b/compiler/rustc_target/src/spec/mipsel_sony_psx.rs
new file mode 100644
index 000000000000..12a66efdd46f
--- /dev/null
+++ b/compiler/rustc_target/src/spec/mipsel_sony_psx.rs
@@ -0,0 +1,37 @@
+use crate::spec::{cvs, Cc, LinkerFlavor, Lld, PanicStrategy, RelocModel, Target, TargetOptions};
+
+pub fn target() -> Target {
+    Target {
+        llvm_target: "mipsel-sony-psx".into(),
+        pointer_width: 32,
+        data_layout: "e-m:m-p:32:32-i8:8:32-i16:16:32-i64:64-n32-S64".into(),
+        arch: "mips".into(),
+
+        options: TargetOptions {
+            os: "none".into(),
+            env: "psx".into(),
+            vendor: "sony".into(),
+            linker_flavor: LinkerFlavor::Gnu(Cc::No, Lld::Yes),
+            cpu: "mips1".into(),
+            executables: true,
+            linker: Some("rust-lld".into()),
+            relocation_model: RelocModel::Static,
+            exe_suffix: ".exe".into(),
+
+            // PSX doesn't natively support floats.
+            features: "+soft-float".into(),
+
+            // This should be 16 bits, but LLVM incorrectly tries emitting MIPS-II SYNC instructions
+            // for atomic loads and stores. This crashes rustc so we have to disable the Atomic* API
+            // until this is fixed upstream. See https://reviews.llvm.org/D122427#3420144 for more
+            // info.
+            max_atomic_width: Some(0),
+
+            // PSX does not support trap-on-condition instructions.
+            llvm_args: cvs!["-mno-check-zero-division"],
+            llvm_abiname: "o32".into(),
+            panic_strategy: PanicStrategy::Abort,
+            ..Default::default()
+        },
+    }
+}
diff --git a/compiler/rustc_target/src/spec/mod.rs b/compiler/rustc_target/src/spec/mod.rs
index 8909cf33af91..664592b02a12 100644
--- a/compiler/rustc_target/src/spec/mod.rs
+++ b/compiler/rustc_target/src/spec/mod.rs
@@ -59,7 +59,6 @@ pub mod crt_objects;
 
 mod android_base;
 mod apple_base;
-mod apple_sdk_base;
 mod avr_gnu_base;
 mod bpf_base;
 mod dragonfly_base;
@@ -71,11 +70,11 @@ mod illumos_base;
 mod l4re_base;
 mod linux_base;
 mod linux_gnu_base;
-mod linux_kernel_base;
 mod linux_musl_base;
 mod linux_uclibc_base;
 mod msvc_base;
 mod netbsd_base;
+mod nto_qnx_base;
 mod openbsd_base;
 mod redox_base;
 mod solaris_base;
@@ -115,7 +114,7 @@ pub enum Lld {
 /// relevant now.
 ///
 /// The second goal is to keep the number of flavors to the minimum if possible.
-/// LLD somewhat forces our hand here because that linker is self-sufficent only if its executable
+/// LLD somewhat forces our hand here because that linker is self-sufficient only if its executable
 /// (`argv[0]`) is named in specific way, otherwise it doesn't work and requires a
 /// `-flavor LLD_FLAVOR` argument to choose which logic to use. Our shipped `rust-lld` in
 /// particular is not named in such specific way, so it needs the flavor option, so we make our
@@ -1003,7 +1002,7 @@ macro_rules! supported_targets {
             $(
                 #[test] // `#[test]`
                 fn $module() {
-                    tests_impl::test_target(super::$module::target(), $triple);
+                    tests_impl::test_target(super::$module::target());
                 }
             )+
         }
@@ -1071,8 +1070,6 @@ supported_targets! {
     ("thumbv7neon-linux-androideabi", thumbv7neon_linux_androideabi),
     ("aarch64-linux-android", aarch64_linux_android),
 
-    ("x86_64-unknown-none-linuxkernel", x86_64_unknown_none_linuxkernel),
-
     ("aarch64-unknown-freebsd", aarch64_unknown_freebsd),
     ("armv6-unknown-freebsd", armv6_unknown_freebsd),
     ("armv7-unknown-freebsd", armv7_unknown_freebsd),
@@ -1222,6 +1219,7 @@ supported_targets! {
     ("armv7a-kmc-solid_asp3-eabihf", armv7a_kmc_solid_asp3_eabihf),
 
     ("mipsel-sony-psp", mipsel_sony_psp),
+    ("mipsel-sony-psx", mipsel_sony_psx),
     ("mipsel-unknown-none", mipsel_unknown_none),
     ("thumbv4t-none-eabi", thumbv4t_none_eabi),
     ("armv4t-none-eabi", armv4t_none_eabi),
@@ -1245,6 +1243,9 @@ supported_targets! {
     ("x86_64-unknown-none", x86_64_unknown_none),
 
     ("mips64-openwrt-linux-musl", mips64_openwrt_linux_musl),
+
+    ("aarch64-unknown-nto-qnx7.1.0", aarch64_unknown_nto_qnx_710),
+    ("x86_64-pc-nto-qnx7.1.0", x86_64_pc_nto_qnx710),
 }
 
 /// Cow-Vec-Str: Cow<'static, [Cow<'static, str>]>
@@ -1914,6 +1915,7 @@ impl Target {
                 Abi::Stdcall { unwind }
             }
             Abi::System { unwind } => Abi::C { unwind },
+            Abi::EfiApi if self.arch == "arm" => Abi::Aapcs { unwind: false },
             Abi::EfiApi if self.arch == "x86_64" => Abi::Win64 { unwind: false },
             Abi::EfiApi => Abi::C { unwind: false },
 
@@ -1940,8 +1942,10 @@ impl Target {
             | PlatformIntrinsic
             | Unadjusted
             | Cdecl { .. }
-            | EfiApi
             | RustCold => true,
+            EfiApi => {
+                ["arm", "aarch64", "riscv32", "riscv64", "x86", "x86_64"].contains(&&self.arch[..])
+            }
             X86Interrupt => ["x86", "x86_64"].contains(&&self.arch[..]),
             Aapcs { .. } => "arm" == self.arch,
             CCmseNonSecureCall => ["arm", "aarch64"].contains(&&self.arch[..]),
diff --git a/compiler/rustc_target/src/spec/nto_qnx_base.rs b/compiler/rustc_target/src/spec/nto_qnx_base.rs
new file mode 100644
index 000000000000..6fb581ef5ce3
--- /dev/null
+++ b/compiler/rustc_target/src/spec/nto_qnx_base.rs
@@ -0,0 +1,19 @@
+use crate::spec::{cvs, RelroLevel, TargetOptions};
+
+pub fn opts() -> TargetOptions {
+    TargetOptions {
+        crt_static_respected: true,
+        dynamic_linking: true,
+        env: "nto71".into(),
+        executables: true,
+        families: cvs!["unix"],
+        has_rpath: true,
+        has_thread_local: false,
+        linker: Some("qcc".into()),
+        os: "nto".into(),
+        position_independent_executables: true,
+        static_position_independent_executables: true,
+        relro_level: RelroLevel::Full,
+        ..Default::default()
+    }
+}
diff --git a/compiler/rustc_target/src/spec/riscv64gc_unknown_freebsd.rs b/compiler/rustc_target/src/spec/riscv64gc_unknown_freebsd.rs
index 0539eca6c1fc..8281bac10f88 100644
--- a/compiler/rustc_target/src/spec/riscv64gc_unknown_freebsd.rs
+++ b/compiler/rustc_target/src/spec/riscv64gc_unknown_freebsd.rs
@@ -4,7 +4,7 @@ pub fn target() -> Target {
     Target {
         llvm_target: "riscv64-unknown-freebsd".into(),
         pointer_width: 64,
-        data_layout: "e-m:e-p:64:64-i64:64-i128:128-n64-S128".into(),
+        data_layout: "e-m:e-p:64:64-i64:64-i128:128-n32:64-S128".into(),
         arch: "riscv64".into(),
         options: TargetOptions {
             code_model: Some(CodeModel::Medium),
diff --git a/compiler/rustc_target/src/spec/riscv64gc_unknown_linux_gnu.rs b/compiler/rustc_target/src/spec/riscv64gc_unknown_linux_gnu.rs
index 7d1bf228c370..90dccb28063d 100644
--- a/compiler/rustc_target/src/spec/riscv64gc_unknown_linux_gnu.rs
+++ b/compiler/rustc_target/src/spec/riscv64gc_unknown_linux_gnu.rs
@@ -4,7 +4,7 @@ pub fn target() -> Target {
     Target {
         llvm_target: "riscv64-unknown-linux-gnu".into(),
         pointer_width: 64,
-        data_layout: "e-m:e-p:64:64-i64:64-i128:128-n64-S128".into(),
+        data_layout: "e-m:e-p:64:64-i64:64-i128:128-n32:64-S128".into(),
         arch: "riscv64".into(),
         options: TargetOptions {
             code_model: Some(CodeModel::Medium),
diff --git a/compiler/rustc_target/src/spec/riscv64gc_unknown_linux_musl.rs b/compiler/rustc_target/src/spec/riscv64gc_unknown_linux_musl.rs
index f04f8a48bc81..1a56c78e6852 100644
--- a/compiler/rustc_target/src/spec/riscv64gc_unknown_linux_musl.rs
+++ b/compiler/rustc_target/src/spec/riscv64gc_unknown_linux_musl.rs
@@ -4,7 +4,7 @@ pub fn target() -> Target {
     Target {
         llvm_target: "riscv64-unknown-linux-musl".into(),
         pointer_width: 64,
-        data_layout: "e-m:e-p:64:64-i64:64-i128:128-n64-S128".into(),
+        data_layout: "e-m:e-p:64:64-i64:64-i128:128-n32:64-S128".into(),
         arch: "riscv64".into(),
         options: TargetOptions {
             code_model: Some(CodeModel::Medium),
diff --git a/compiler/rustc_target/src/spec/riscv64gc_unknown_none_elf.rs b/compiler/rustc_target/src/spec/riscv64gc_unknown_none_elf.rs
index 67806d578c8e..409b0b269615 100644
--- a/compiler/rustc_target/src/spec/riscv64gc_unknown_none_elf.rs
+++ b/compiler/rustc_target/src/spec/riscv64gc_unknown_none_elf.rs
@@ -3,7 +3,7 @@ use crate::spec::{RelocModel, Target, TargetOptions};
 
 pub fn target() -> Target {
     Target {
-        data_layout: "e-m:e-p:64:64-i64:64-i128:128-n64-S128".into(),
+        data_layout: "e-m:e-p:64:64-i64:64-i128:128-n32:64-S128".into(),
         llvm_target: "riscv64".into(),
         pointer_width: 64,
         arch: "riscv64".into(),
diff --git a/compiler/rustc_target/src/spec/riscv64gc_unknown_openbsd.rs b/compiler/rustc_target/src/spec/riscv64gc_unknown_openbsd.rs
index cd10f3afaac0..ade9d77624bd 100644
--- a/compiler/rustc_target/src/spec/riscv64gc_unknown_openbsd.rs
+++ b/compiler/rustc_target/src/spec/riscv64gc_unknown_openbsd.rs
@@ -4,7 +4,7 @@ pub fn target() -> Target {
     Target {
         llvm_target: "riscv64-unknown-openbsd".into(),
         pointer_width: 64,
-        data_layout: "e-m:e-p:64:64-i64:64-i128:128-n64-S128".into(),
+        data_layout: "e-m:e-p:64:64-i64:64-i128:128-n32:64-S128".into(),
         arch: "riscv64".into(),
         options: TargetOptions {
             code_model: Some(CodeModel::Medium),
diff --git a/compiler/rustc_target/src/spec/riscv64imac_unknown_none_elf.rs b/compiler/rustc_target/src/spec/riscv64imac_unknown_none_elf.rs
index f371e09bed74..87aba9171b41 100644
--- a/compiler/rustc_target/src/spec/riscv64imac_unknown_none_elf.rs
+++ b/compiler/rustc_target/src/spec/riscv64imac_unknown_none_elf.rs
@@ -3,7 +3,7 @@ use crate::spec::{RelocModel, Target, TargetOptions};
 
 pub fn target() -> Target {
     Target {
-        data_layout: "e-m:e-p:64:64-i64:64-i128:128-n64-S128".into(),
+        data_layout: "e-m:e-p:64:64-i64:64-i128:128-n32:64-S128".into(),
         llvm_target: "riscv64".into(),
         pointer_width: 64,
         arch: "riscv64".into(),
diff --git a/compiler/rustc_target/src/spec/tests/tests_impl.rs b/compiler/rustc_target/src/spec/tests/tests_impl.rs
index 172da0ed5df8..e0ecf8037c3e 100644
--- a/compiler/rustc_target/src/spec/tests/tests_impl.rs
+++ b/compiler/rustc_target/src/spec/tests/tests_impl.rs
@@ -2,15 +2,15 @@ use super::super::*;
 use std::assert_matches::assert_matches;
 
 // Test target self-consistency and JSON encoding/decoding roundtrip.
-pub(super) fn test_target(mut target: Target, triple: &str) {
+pub(super) fn test_target(mut target: Target) {
     let recycled_target = Target::from_json(target.to_json()).map(|(j, _)| j);
     target.update_to_cli();
-    target.check_consistency(triple);
+    target.check_consistency();
     assert_eq!(recycled_target, Ok(target));
 }
 
 impl Target {
-    fn check_consistency(&self, triple: &str) {
+    fn check_consistency(&self) {
         assert_eq!(self.is_like_osx, self.vendor == "apple");
         assert_eq!(self.is_like_solaris, self.os == "solaris" || self.os == "illumos");
         assert_eq!(self.is_like_windows, self.os == "windows" || self.os == "uefi");
@@ -129,8 +129,7 @@ impl Target {
         if self.dynamic_linking && !(self.is_like_wasm && self.os != "emscripten") {
             assert_eq!(self.relocation_model, RelocModel::Pic);
         }
-        // PIEs are supported but not enabled by default with linuxkernel target.
-        if self.position_independent_executables && !triple.ends_with("-linuxkernel") {
+        if self.position_independent_executables {
             assert_eq!(self.relocation_model, RelocModel::Pic);
         }
         // The UEFI targets do not support dynamic linking but still require PIC (#101377).
diff --git a/compiler/rustc_target/src/spec/windows_gnullvm_base.rs b/compiler/rustc_target/src/spec/windows_gnullvm_base.rs
index 58210c75a3da..cada28652f98 100644
--- a/compiler/rustc_target/src/spec/windows_gnullvm_base.rs
+++ b/compiler/rustc_target/src/spec/windows_gnullvm_base.rs
@@ -1,4 +1,5 @@
-use crate::spec::{cvs, Cc, LinkerFlavor, Lld, TargetOptions};
+use crate::spec::{cvs, Cc, DebuginfoKind, LinkerFlavor, Lld, SplitDebuginfo, TargetOptions};
+use std::borrow::Cow;
 
 pub fn opts() -> TargetOptions {
     // We cannot use `-nodefaultlibs` because compiler-rt has to be passed
@@ -36,7 +37,10 @@ pub fn opts() -> TargetOptions {
         eh_frame_header: false,
         no_default_libraries: false,
         has_thread_local: true,
-
+        // FIXME(davidtwco): Support Split DWARF on Windows GNU - may require LLVM changes to
+        // output DWO, despite using DWARF, doesn't use ELF..
+        debuginfo_kind: DebuginfoKind::Pdb,
+        supported_split_debuginfo: Cow::Borrowed(&[SplitDebuginfo::Off]),
         ..Default::default()
     }
 }
diff --git a/compiler/rustc_target/src/spec/x86_64_apple_darwin.rs b/compiler/rustc_target/src/spec/x86_64_apple_darwin.rs
index 087be1b957b1..c053031612ce 100644
--- a/compiler/rustc_target/src/spec/x86_64_apple_darwin.rs
+++ b/compiler/rustc_target/src/spec/x86_64_apple_darwin.rs
@@ -1,29 +1,27 @@
+use super::apple_base::{macos_link_env_remove, macos_llvm_target, opts, Arch};
 use crate::spec::{Cc, FramePointer, LinkerFlavor, Lld, SanitizerSet};
 use crate::spec::{StackProbeType, Target, TargetOptions};
 
 pub fn target() -> Target {
-    let arch = "x86_64";
-    let mut base = super::apple_base::opts("macos", arch, "");
-    base.cpu = "core2".into();
-    base.max_atomic_width = Some(128); // core2 support cmpxchg16b
+    let arch = Arch::X86_64;
+    let mut base = opts("macos", arch);
+    base.max_atomic_width = Some(128); // core2 supports cmpxchg16b
     base.frame_pointer = FramePointer::Always;
     base.add_pre_link_args(LinkerFlavor::Darwin(Cc::Yes, Lld::No), &["-m64"]);
-    base.link_env_remove.to_mut().extend(super::apple_base::macos_link_env_remove());
+    base.link_env_remove.to_mut().extend(macos_link_env_remove());
     base.stack_probes = StackProbeType::X86;
     base.supported_sanitizers =
         SanitizerSet::ADDRESS | SanitizerSet::CFI | SanitizerSet::LEAK | SanitizerSet::THREAD;
 
-    // Clang automatically chooses a more specific target based on
-    // MACOSX_DEPLOYMENT_TARGET.  To enable cross-language LTO to work
-    // correctly, we do too.
-    let llvm_target = super::apple_base::macos_llvm_target(&arch);
-
     Target {
-        llvm_target: llvm_target.into(),
+        // Clang automatically chooses a more specific target based on
+        // MACOSX_DEPLOYMENT_TARGET.  To enable cross-language LTO to work
+        // correctly, we do too.
+        llvm_target: macos_llvm_target(arch).into(),
         pointer_width: 64,
         data_layout: "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
             .into(),
-        arch: arch.into(),
+        arch: arch.target_arch(),
         options: TargetOptions { mcount: "\u{1}mcount".into(), ..base },
     }
 }
diff --git a/compiler/rustc_target/src/spec/x86_64_apple_ios.rs b/compiler/rustc_target/src/spec/x86_64_apple_ios.rs
index e6143025d6d2..fbd3ebd4d043 100644
--- a/compiler/rustc_target/src/spec/x86_64_apple_ios.rs
+++ b/compiler/rustc_target/src/spec/x86_64_apple_ios.rs
@@ -1,20 +1,18 @@
-use super::apple_sdk_base::{opts, Arch};
+use super::apple_base::{ios_sim_llvm_target, opts, Arch};
 use crate::spec::{StackProbeType, Target, TargetOptions};
 
 pub fn target() -> Target {
-    let base = opts("ios", Arch::X86_64);
-    let llvm_target = super::apple_base::ios_sim_llvm_target("x86_64");
-
+    let arch = Arch::X86_64_sim;
     Target {
-        llvm_target: llvm_target.into(),
+        llvm_target: ios_sim_llvm_target(arch).into(),
         pointer_width: 64,
         data_layout: "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
             .into(),
-        arch: "x86_64".into(),
+        arch: arch.target_arch(),
         options: TargetOptions {
             max_atomic_width: Some(64),
             stack_probes: StackProbeType::X86,
-            ..base
+            ..opts("ios", arch)
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/x86_64_apple_ios_macabi.rs b/compiler/rustc_target/src/spec/x86_64_apple_ios_macabi.rs
index 13259205ac0f..0f3f85199637 100644
--- a/compiler/rustc_target/src/spec/x86_64_apple_ios_macabi.rs
+++ b/compiler/rustc_target/src/spec/x86_64_apple_ios_macabi.rs
@@ -1,10 +1,11 @@
-use super::apple_sdk_base::{opts, Arch};
+use super::apple_base::{opts, Arch};
 use crate::spec::{Cc, LinkerFlavor, Lld, StackProbeType, Target, TargetOptions};
 
 pub fn target() -> Target {
     let llvm_target = "x86_64-apple-ios13.0-macabi";
 
-    let mut base = opts("ios", Arch::X86_64_macabi);
+    let arch = Arch::X86_64_macabi;
+    let mut base = opts("ios", arch);
     base.add_pre_link_args(LinkerFlavor::Darwin(Cc::Yes, Lld::No), &["-target", llvm_target]);
 
     Target {
@@ -12,7 +13,7 @@ pub fn target() -> Target {
         pointer_width: 64,
         data_layout: "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
             .into(),
-        arch: "x86_64".into(),
+        arch: arch.target_arch(),
         options: TargetOptions {
             max_atomic_width: Some(64),
             stack_probes: StackProbeType::X86,
diff --git a/compiler/rustc_target/src/spec/x86_64_apple_tvos.rs b/compiler/rustc_target/src/spec/x86_64_apple_tvos.rs
index 3d54da0867cf..550ce0b9ce57 100644
--- a/compiler/rustc_target/src/spec/x86_64_apple_tvos.rs
+++ b/compiler/rustc_target/src/spec/x86_64_apple_tvos.rs
@@ -1,17 +1,17 @@
-use super::apple_sdk_base::{opts, Arch};
+use super::apple_base::{opts, Arch};
 use crate::spec::{StackProbeType, Target, TargetOptions};
 
 pub fn target() -> Target {
-    let base = opts("tvos", Arch::X86_64);
+    let arch = Arch::X86_64_sim;
     Target {
         llvm_target: "x86_64-apple-tvos".into(),
         pointer_width: 64,
         data_layout: "e-m:o-i64:64-f80:128-n8:16:32:64-S128".into(),
-        arch: "x86_64".into(),
+        arch: arch.target_arch(),
         options: TargetOptions {
             max_atomic_width: Some(64),
             stack_probes: StackProbeType::X86,
-            ..base
+            ..opts("tvos", arch)
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/x86_64_apple_watchos_sim.rs b/compiler/rustc_target/src/spec/x86_64_apple_watchos_sim.rs
index e499b1985e76..75ce02cba1de 100644
--- a/compiler/rustc_target/src/spec/x86_64_apple_watchos_sim.rs
+++ b/compiler/rustc_target/src/spec/x86_64_apple_watchos_sim.rs
@@ -1,18 +1,14 @@
-use super::apple_sdk_base::{opts, Arch};
+use super::apple_base::{opts, watchos_sim_llvm_target, Arch};
 use crate::spec::{StackProbeType, Target, TargetOptions};
 
 pub fn target() -> Target {
-    let base = opts("watchos", Arch::X86_64);
-
-    let arch = "x86_64";
-    let llvm_target = super::apple_base::watchos_sim_llvm_target(arch);
-
+    let arch = Arch::X86_64_sim;
     Target {
-        llvm_target: llvm_target.into(),
+        llvm_target: watchos_sim_llvm_target(arch).into(),
         pointer_width: 64,
         data_layout: "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
             .into(),
-        arch: "x86_64".into(),
+        arch: arch.target_arch(),
         options: TargetOptions {
             max_atomic_width: Some(64),
             stack_probes: StackProbeType::X86,
@@ -28,7 +24,7 @@ pub fn target() -> Target {
                 darwinpcs\0\
                 -Os\0"
                 .into(),
-            ..base
+            ..opts("watchos", arch)
         },
     }
 }
diff --git a/compiler/rustc_target/src/spec/x86_64_pc_nto_qnx710.rs b/compiler/rustc_target/src/spec/x86_64_pc_nto_qnx710.rs
new file mode 100644
index 000000000000..e9b3acee2e7f
--- /dev/null
+++ b/compiler/rustc_target/src/spec/x86_64_pc_nto_qnx710.rs
@@ -0,0 +1,21 @@
+use super::nto_qnx_base;
+use crate::spec::{Cc, LinkerFlavor, Lld, Target, TargetOptions};
+
+pub fn target() -> Target {
+    Target {
+        llvm_target: "x86_64-pc-unknown".into(),
+        pointer_width: 64,
+        data_layout: "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+            .into(),
+        arch: "x86_64".into(),
+        options: TargetOptions {
+            cpu: "x86-64".into(),
+            max_atomic_width: Some(64),
+            pre_link_args: TargetOptions::link_args(
+                LinkerFlavor::Gnu(Cc::Yes, Lld::No),
+                &["-Vgcc_ntox86_64_cxx"],
+            ),
+            ..nto_qnx_base::opts()
+        },
+    }
+}
diff --git a/compiler/rustc_target/src/spec/x86_64_unknown_none_linuxkernel.rs b/compiler/rustc_target/src/spec/x86_64_unknown_none_linuxkernel.rs
deleted file mode 100644
index ebd9636ff510..000000000000
--- a/compiler/rustc_target/src/spec/x86_64_unknown_none_linuxkernel.rs
+++ /dev/null
@@ -1,28 +0,0 @@
-// This defines the amd64 target for the Linux Kernel. See the linux-kernel-base module for
-// generic Linux kernel options.
-
-use crate::spec::{Cc, CodeModel, LinkerFlavor, Lld, Target};
-
-pub fn target() -> Target {
-    let mut base = super::linux_kernel_base::opts();
-    base.cpu = "x86-64".into();
-    base.max_atomic_width = Some(64);
-    base.features =
-        "-mmx,-sse,-sse2,-sse3,-ssse3,-sse4.1,-sse4.2,-3dnow,-3dnowa,-avx,-avx2,+soft-float".into();
-    base.code_model = Some(CodeModel::Kernel);
-    base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-m64"]);
-
-    Target {
-        // FIXME: Some dispute, the linux-on-clang folks think this should use
-        // "Linux". We disagree because running *on* Linux is nothing like
-        // running *as" linux, and historically the "os" component as has always
-        // been used to mean the "on" part.
-        llvm_target: "x86_64-unknown-none-elf".into(),
-        pointer_width: 64,
-        data_layout: "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
-            .into(),
-        arch: "x86_64".into(),
-
-        options: base,
-    }
-}
diff --git a/compiler/rustc_trait_selection/src/autoderef.rs b/compiler/rustc_trait_selection/src/autoderef.rs
index 61cfeec4bbb6..54c738d83897 100644
--- a/compiler/rustc_trait_selection/src/autoderef.rs
+++ b/compiler/rustc_trait_selection/src/autoderef.rs
@@ -1,6 +1,6 @@
 use crate::errors::AutoDerefReachedRecursionLimit;
 use crate::traits::query::evaluate_obligation::InferCtxtExt;
-use crate::traits::{self, TraitEngine};
+use crate::traits::{self, TraitEngine, TraitEngineExt};
 use rustc_hir as hir;
 use rustc_infer::infer::InferCtxt;
 use rustc_middle::ty::{self, TraitRef, Ty, TyCtxt};
@@ -27,7 +27,6 @@ pub struct Autoderef<'a, 'tcx> {
     // Meta infos:
     infcx: &'a InferCtxt<'tcx>,
     span: Span,
-    overloaded_span: Span,
     body_id: hir::HirId,
     param_env: ty::ParamEnv<'tcx>,
 
@@ -99,12 +98,10 @@ impl<'a, 'tcx> Autoderef<'a, 'tcx> {
         body_id: hir::HirId,
         span: Span,
         base_ty: Ty<'tcx>,
-        overloaded_span: Span,
     ) -> Autoderef<'a, 'tcx> {
         Autoderef {
             infcx,
             span,
-            overloaded_span,
             body_id,
             param_env,
             state: AutoderefSnapshot {
@@ -142,7 +139,7 @@ impl<'a, 'tcx> Autoderef<'a, 'tcx> {
             return None;
         }
 
-        let mut fulfillcx = traits::FulfillmentContext::new_in_snapshot();
+        let mut fulfillcx = <dyn TraitEngine<'tcx>>::new_in_snapshot(tcx);
         let normalized_ty = fulfillcx.normalize_projection_type(
             &self.infcx,
             self.param_env,
@@ -193,10 +190,6 @@ impl<'a, 'tcx> Autoderef<'a, 'tcx> {
         self.span
     }
 
-    pub fn overloaded_span(&self) -> Span {
-        self.overloaded_span
-    }
-
     pub fn reached_recursion_limit(&self) -> bool {
         self.state.reached_recursion_limit
     }
diff --git a/compiler/rustc_trait_selection/src/errors.rs b/compiler/rustc_trait_selection/src/errors.rs
index 7f8705824445..19f404cb5b78 100644
--- a/compiler/rustc_trait_selection/src/errors.rs
+++ b/compiler/rustc_trait_selection/src/errors.rs
@@ -58,24 +58,25 @@ pub struct NoValueInOnUnimplemented {
     pub span: Span,
 }
 
-pub struct NegativePositiveConflict<'a> {
+pub struct NegativePositiveConflict<'tcx> {
     pub impl_span: Span,
-    pub trait_desc: &'a str,
-    pub self_desc: &'a Option<String>,
+    pub trait_desc: ty::TraitRef<'tcx>,
+    pub self_ty: Option<Ty<'tcx>>,
     pub negative_impl_span: Result<Span, Symbol>,
     pub positive_impl_span: Result<Span, Symbol>,
 }
 
 impl IntoDiagnostic<'_> for NegativePositiveConflict<'_> {
+    #[track_caller]
     fn into_diagnostic(
         self,
         handler: &Handler,
     ) -> rustc_errors::DiagnosticBuilder<'_, ErrorGuaranteed> {
         let mut diag = handler.struct_err(fluent::trait_selection_negative_positive_conflict);
-        diag.set_arg("trait_desc", self.trait_desc);
+        diag.set_arg("trait_desc", self.trait_desc.print_only_trait_path().to_string());
         diag.set_arg(
             "self_desc",
-            self.self_desc.clone().map_or_else(|| String::from("none"), |ty| ty),
+            self.self_ty.map_or_else(|| "none".to_string(), |ty| ty.to_string()),
         );
         diag.set_span(self.impl_span);
         diag.code(rustc_errors::error_code!(E0751));
diff --git a/compiler/rustc_trait_selection/src/infer.rs b/compiler/rustc_trait_selection/src/infer.rs
index 1b58c9b864e4..0f2e22604dc7 100644
--- a/compiler/rustc_trait_selection/src/infer.rs
+++ b/compiler/rustc_trait_selection/src/infer.rs
@@ -1,5 +1,5 @@
 use crate::traits::query::evaluate_obligation::InferCtxtExt as _;
-use crate::traits::{self, TraitEngine, TraitEngineExt};
+use crate::traits::{self, ObligationCtxt};
 
 use rustc_hir::def_id::DefId;
 use rustc_hir::lang_items::LangItem;
@@ -69,7 +69,7 @@ impl<'tcx> InferCtxtExt<'tcx> for InferCtxt<'tcx> {
         let ty = self.resolve_vars_if_possible(ty);
 
         if !(param_env, ty).needs_infer() {
-            return ty.is_copy_modulo_regions(self.tcx.at(span), param_env);
+            return ty.is_copy_modulo_regions(self.tcx, param_env);
         }
 
         let copy_def_id = self.tcx.require_lang_item(LangItem::Copy, None);
@@ -93,6 +93,7 @@ impl<'tcx> InferCtxtExt<'tcx> for InferCtxt<'tcx> {
 
     /// Normalizes associated types in `value`, potentially returning
     /// new obligations that must further be processed.
+    #[instrument(level = "debug", skip(self, cause, param_env), ret)]
     fn partially_normalize_associated_types_in<T>(
         &self,
         cause: ObligationCause<'tcx>,
@@ -102,17 +103,13 @@ impl<'tcx> InferCtxtExt<'tcx> for InferCtxt<'tcx> {
     where
         T: TypeFoldable<'tcx>,
     {
-        debug!("partially_normalize_associated_types_in(value={:?})", value);
         let mut selcx = traits::SelectionContext::new(self);
         let traits::Normalized { value, obligations } =
             traits::normalize(&mut selcx, param_env, cause, value);
-        debug!(
-            "partially_normalize_associated_types_in: result={:?} predicates={:?}",
-            value, obligations
-        );
         InferOk { value, obligations }
     }
 
+    #[instrument(level = "debug", skip(self), ret)]
     fn type_implements_trait(
         &self,
         trait_def_id: DefId,
@@ -120,11 +117,6 @@ impl<'tcx> InferCtxtExt<'tcx> for InferCtxt<'tcx> {
         params: SubstsRef<'tcx>,
         param_env: ty::ParamEnv<'tcx>,
     ) -> traits::EvaluationResult {
-        debug!(
-            "type_implements_trait: trait_def_id={:?}, type={:?}, params={:?}, param_env={:?}",
-            trait_def_id, ty, params, param_env
-        );
-
         let trait_ref =
             ty::TraitRef { def_id: trait_def_id, substs: self.tcx.mk_substs_trait(ty, params) };
 
@@ -142,7 +134,7 @@ pub trait InferCtxtBuilderExt<'tcx> {
     fn enter_canonical_trait_query<K, R>(
         &mut self,
         canonical_key: &Canonical<'tcx, K>,
-        operation: impl FnOnce(&InferCtxt<'tcx>, &mut dyn TraitEngine<'tcx>, K) -> Fallible<R>,
+        operation: impl FnOnce(&ObligationCtxt<'_, 'tcx>, K) -> Fallible<R>,
     ) -> Fallible<CanonicalizedQueryResponse<'tcx, R>>
     where
         K: TypeFoldable<'tcx>,
@@ -170,17 +162,17 @@ impl<'tcx> InferCtxtBuilderExt<'tcx> for InferCtxtBuilder<'tcx> {
     fn enter_canonical_trait_query<K, R>(
         &mut self,
         canonical_key: &Canonical<'tcx, K>,
-        operation: impl FnOnce(&InferCtxt<'tcx>, &mut dyn TraitEngine<'tcx>, K) -> Fallible<R>,
+        operation: impl FnOnce(&ObligationCtxt<'_, 'tcx>, K) -> Fallible<R>,
     ) -> Fallible<CanonicalizedQueryResponse<'tcx, R>>
     where
         K: TypeFoldable<'tcx>,
         R: Debug + TypeFoldable<'tcx>,
         Canonical<'tcx, QueryResponse<'tcx, R>>: ArenaAllocatable<'tcx>,
     {
-        let (ref infcx, key, canonical_inference_vars) =
+        let (infcx, key, canonical_inference_vars) =
             self.build_with_canonical(DUMMY_SP, canonical_key);
-        let mut fulfill_cx = <dyn TraitEngine<'_>>::new(infcx.tcx);
-        let value = operation(infcx, &mut *fulfill_cx, key)?;
-        infcx.make_canonicalized_query_response(canonical_inference_vars, value, &mut *fulfill_cx)
+        let ocx = ObligationCtxt::new(&infcx);
+        let value = operation(&ocx, key)?;
+        ocx.make_canonicalized_query_response(canonical_inference_vars, value)
     }
 }
diff --git a/compiler/rustc_trait_selection/src/lib.rs b/compiler/rustc_trait_selection/src/lib.rs
index 5d52aa075230..2dce18e2d3ca 100644
--- a/compiler/rustc_trait_selection/src/lib.rs
+++ b/compiler/rustc_trait_selection/src/lib.rs
@@ -10,7 +10,6 @@
 //!
 //! This API is completely unstable and subject to change.
 
-#![allow(rustc::potential_query_instability)]
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
 #![feature(box_patterns)]
 #![feature(control_flow_enum)]
diff --git a/compiler/rustc_trait_selection/src/traits/auto_trait.rs b/compiler/rustc_trait_selection/src/traits/auto_trait.rs
index ed34ab95ad6c..188f8bb7e2a5 100644
--- a/compiler/rustc_trait_selection/src/traits/auto_trait.rs
+++ b/compiler/rustc_trait_selection/src/traits/auto_trait.rs
@@ -12,7 +12,7 @@ use rustc_middle::ty::fold::{TypeFolder, TypeSuperFoldable};
 use rustc_middle::ty::visit::TypeVisitable;
 use rustc_middle::ty::{PolyTraitRef, Region, RegionVid};
 
-use rustc_data_structures::fx::{FxHashMap, FxHashSet};
+use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexSet};
 
 use std::collections::hash_map::Entry;
 use std::collections::VecDeque;
@@ -27,8 +27,8 @@ pub enum RegionTarget<'tcx> {
 
 #[derive(Default, Debug, Clone)]
 pub struct RegionDeps<'tcx> {
-    larger: FxHashSet<RegionTarget<'tcx>>,
-    smaller: FxHashSet<RegionTarget<'tcx>>,
+    larger: FxIndexSet<RegionTarget<'tcx>>,
+    smaller: FxIndexSet<RegionTarget<'tcx>>,
 }
 
 pub enum AutoTraitResult<A> {
@@ -266,7 +266,7 @@ impl<'tcx> AutoTraitFinder<'tcx> {
         }));
 
         let computed_preds = param_env.caller_bounds().iter();
-        let mut user_computed_preds: FxHashSet<_> = user_env.caller_bounds().iter().collect();
+        let mut user_computed_preds: FxIndexSet<_> = user_env.caller_bounds().iter().collect();
 
         let mut new_env = param_env;
         let dummy_cause = ObligationCause::dummy();
@@ -389,7 +389,7 @@ impl<'tcx> AutoTraitFinder<'tcx> {
     /// not just one specific lifetime (e.g., `'static`).
     fn add_user_pred(
         &self,
-        user_computed_preds: &mut FxHashSet<ty::Predicate<'tcx>>,
+        user_computed_preds: &mut FxIndexSet<ty::Predicate<'tcx>>,
         new_pred: ty::Predicate<'tcx>,
     ) {
         let mut should_add_new = true;
@@ -585,7 +585,7 @@ impl<'tcx> AutoTraitFinder<'tcx> {
         &self,
         ty: Ty<'_>,
         nested: impl Iterator<Item = Obligation<'tcx, ty::Predicate<'tcx>>>,
-        computed_preds: &mut FxHashSet<ty::Predicate<'tcx>>,
+        computed_preds: &mut FxIndexSet<ty::Predicate<'tcx>>,
         fresh_preds: &mut FxHashSet<ty::Predicate<'tcx>>,
         predicates: &mut VecDeque<ty::PolyTraitPredicate<'tcx>>,
         select: &mut SelectionContext<'_, 'tcx>,
diff --git a/compiler/rustc_trait_selection/src/traits/chalk_fulfill.rs b/compiler/rustc_trait_selection/src/traits/chalk_fulfill.rs
index 81e1d64493e1..8f9d5eaac9d1 100644
--- a/compiler/rustc_trait_selection/src/traits/chalk_fulfill.rs
+++ b/compiler/rustc_trait_selection/src/traits/chalk_fulfill.rs
@@ -14,15 +14,22 @@ pub struct FulfillmentContext<'tcx> {
     obligations: FxIndexSet<PredicateObligation<'tcx>>,
 
     relationships: FxHashMap<ty::TyVid, ty::FoundRelationships>,
+
+    usable_in_snapshot: bool,
 }
 
 impl FulfillmentContext<'_> {
-    pub(crate) fn new() -> Self {
+    pub(super) fn new() -> Self {
         FulfillmentContext {
             obligations: FxIndexSet::default(),
             relationships: FxHashMap::default(),
+            usable_in_snapshot: false,
         }
     }
+
+    pub(crate) fn new_in_snapshot() -> Self {
+        FulfillmentContext { usable_in_snapshot: true, ..Self::new() }
+    }
 }
 
 impl<'tcx> TraitEngine<'tcx> for FulfillmentContext<'tcx> {
@@ -41,7 +48,9 @@ impl<'tcx> TraitEngine<'tcx> for FulfillmentContext<'tcx> {
         infcx: &InferCtxt<'tcx>,
         obligation: PredicateObligation<'tcx>,
     ) {
-        assert!(!infcx.is_in_snapshot());
+        if !self.usable_in_snapshot {
+            assert!(!infcx.is_in_snapshot());
+        }
         let obligation = infcx.resolve_vars_if_possible(obligation);
 
         super::relationships::update(self, infcx, &obligation);
@@ -72,7 +81,9 @@ impl<'tcx> TraitEngine<'tcx> for FulfillmentContext<'tcx> {
     }
 
     fn select_where_possible(&mut self, infcx: &InferCtxt<'tcx>) -> Vec<FulfillmentError<'tcx>> {
-        assert!(!infcx.is_in_snapshot());
+        if !self.usable_in_snapshot {
+            assert!(!infcx.is_in_snapshot());
+        }
 
         let mut errors = Vec::new();
         let mut next_round = FxIndexSet::default();
diff --git a/compiler/rustc_trait_selection/src/traits/coherence.rs b/compiler/rustc_trait_selection/src/traits/coherence.rs
index 8aab75490a81..3cf2959a9ffc 100644
--- a/compiler/rustc_trait_selection/src/traits/coherence.rs
+++ b/compiler/rustc_trait_selection/src/traits/coherence.rs
@@ -64,13 +64,13 @@ pub fn add_placeholder_note(err: &mut Diagnostic) {
 /// with a suitably-freshened `ImplHeader` with those types
 /// substituted. Otherwise, returns `None`.
 #[instrument(skip(tcx, skip_leak_check), level = "debug")]
-pub fn overlapping_impls(
-    tcx: TyCtxt<'_>,
+pub fn overlapping_impls<'tcx>(
+    tcx: TyCtxt<'tcx>,
     impl1_def_id: DefId,
     impl2_def_id: DefId,
     skip_leak_check: SkipLeakCheck,
     overlap_mode: OverlapMode,
-) -> Option<OverlapResult<'_>> {
+) -> Option<OverlapResult<'tcx>> {
     // Before doing expensive operations like entering an inference context, do
     // a quick check via fast_reject to tell if the impl headers could possibly
     // unify.
diff --git a/compiler/rustc_trait_selection/src/traits/const_evaluatable.rs b/compiler/rustc_trait_selection/src/traits/const_evaluatable.rs
index 84038625fb27..1de85e2f288b 100644
--- a/compiler/rustc_trait_selection/src/traits/const_evaluatable.rs
+++ b/compiler/rustc_trait_selection/src/traits/const_evaluatable.rs
@@ -192,12 +192,12 @@ pub fn is_const_evaluatable<'tcx>(
         }
         let concrete = infcx.const_eval_resolve(param_env, uv, Some(span));
         match concrete {
-            Err(ErrorHandled::TooGeneric) => {
-                Err(NotConstEvaluatable::Error(infcx.tcx.sess.delay_span_bug(
-                    span,
-                    format!("Missing value for constant, but no error reported?"),
-                )))
-            }
+            Err(ErrorHandled::TooGeneric) => Err(NotConstEvaluatable::Error(
+                infcx
+                    .tcx
+                    .sess
+                    .delay_span_bug(span, "Missing value for constant, but no error reported?"),
+            )),
             Err(ErrorHandled::Linted) => {
                 let reported = infcx
                     .tcx
diff --git a/compiler/rustc_trait_selection/src/traits/engine.rs b/compiler/rustc_trait_selection/src/traits/engine.rs
index e0c8deec91af..ae29c9f56179 100644
--- a/compiler/rustc_trait_selection/src/traits/engine.rs
+++ b/compiler/rustc_trait_selection/src/traits/engine.rs
@@ -1,14 +1,21 @@
 use std::cell::RefCell;
+use std::fmt::Debug;
 
 use super::TraitEngine;
 use super::{ChalkFulfillmentContext, FulfillmentContext};
 use crate::infer::InferCtxtExt;
-use rustc_data_structures::fx::FxHashSet;
+use rustc_data_structures::fx::FxIndexSet;
 use rustc_hir::def_id::{DefId, LocalDefId};
+use rustc_infer::infer::at::ToTrace;
+use rustc_infer::infer::canonical::{
+    Canonical, CanonicalVarValues, CanonicalizedQueryResponse, QueryResponse,
+};
 use rustc_infer::infer::{InferCtxt, InferOk};
+use rustc_infer::traits::query::Fallible;
 use rustc_infer::traits::{
     FulfillmentError, Obligation, ObligationCause, PredicateObligation, TraitEngineExt as _,
 };
+use rustc_middle::arena::ArenaAllocatable;
 use rustc_middle::ty::error::TypeError;
 use rustc_middle::ty::ToPredicate;
 use rustc_middle::ty::TypeFoldable;
@@ -31,7 +38,7 @@ impl<'tcx> TraitEngineExt<'tcx> for dyn TraitEngine<'tcx> {
 
     fn new_in_snapshot(tcx: TyCtxt<'tcx>) -> Box<Self> {
         if tcx.sess.opts.unstable_opts.chalk {
-            Box::new(ChalkFulfillmentContext::new())
+            Box::new(ChalkFulfillmentContext::new_in_snapshot())
         } else {
             Box::new(FulfillmentContext::new_in_snapshot())
         }
@@ -105,14 +112,27 @@ impl<'a, 'tcx> ObligationCtxt<'a, 'tcx> {
         self.register_infer_ok_obligations(infer_ok)
     }
 
-    pub fn equate_types(
+    pub fn eq<T: ToTrace<'tcx>>(
         &self,
         cause: &ObligationCause<'tcx>,
         param_env: ty::ParamEnv<'tcx>,
-        expected: Ty<'tcx>,
-        actual: Ty<'tcx>,
+        expected: T,
+        actual: T,
     ) -> Result<(), TypeError<'tcx>> {
-        match self.infcx.at(cause, param_env).eq(expected, actual) {
+        self.infcx
+            .at(cause, param_env)
+            .eq(expected, actual)
+            .map(|infer_ok| self.register_infer_ok_obligations(infer_ok))
+    }
+
+    pub fn sup<T: ToTrace<'tcx>>(
+        &self,
+        cause: &ObligationCause<'tcx>,
+        param_env: ty::ParamEnv<'tcx>,
+        expected: T,
+        actual: T,
+    ) -> Result<(), TypeError<'tcx>> {
+        match self.infcx.at(cause, param_env).sup(expected, actual) {
             Ok(InferOk { obligations, value: () }) => {
                 self.register_obligations(obligations);
                 Ok(())
@@ -121,6 +141,10 @@ impl<'a, 'tcx> ObligationCtxt<'a, 'tcx> {
         }
     }
 
+    pub fn select_where_possible(&self) -> Vec<FulfillmentError<'tcx>> {
+        self.engine.borrow_mut().select_where_possible(self.infcx)
+    }
+
     pub fn select_all_or_error(&self) -> Vec<FulfillmentError<'tcx>> {
         self.engine.borrow_mut().select_all_or_error(self.infcx)
     }
@@ -130,10 +154,10 @@ impl<'a, 'tcx> ObligationCtxt<'a, 'tcx> {
         param_env: ty::ParamEnv<'tcx>,
         span: Span,
         def_id: LocalDefId,
-    ) -> FxHashSet<Ty<'tcx>> {
+    ) -> FxIndexSet<Ty<'tcx>> {
         let tcx = self.infcx.tcx;
         let assumed_wf_types = tcx.assumed_wf_types(def_id);
-        let mut implied_bounds = FxHashSet::default();
+        let mut implied_bounds = FxIndexSet::default();
         let hir_id = tcx.hir().local_def_id_to_hir_id(def_id);
         let cause = ObligationCause::misc(span, hir_id);
         for ty in assumed_wf_types {
@@ -154,4 +178,20 @@ impl<'a, 'tcx> ObligationCtxt<'a, 'tcx> {
         }
         implied_bounds
     }
+
+    pub fn make_canonicalized_query_response<T>(
+        &self,
+        inference_vars: CanonicalVarValues<'tcx>,
+        answer: T,
+    ) -> Fallible<CanonicalizedQueryResponse<'tcx, T>>
+    where
+        T: Debug + TypeFoldable<'tcx>,
+        Canonical<'tcx, QueryResponse<'tcx, T>>: ArenaAllocatable<'tcx>,
+    {
+        self.infcx.make_canonicalized_query_response(
+            inference_vars,
+            answer,
+            &mut **self.engine.borrow_mut(),
+        )
+    }
 }
diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/ambiguity.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/ambiguity.rs
new file mode 100644
index 000000000000..58da54afb75b
--- /dev/null
+++ b/compiler/rustc_trait_selection/src/traits/error_reporting/ambiguity.rs
@@ -0,0 +1,52 @@
+use rustc_hir::def_id::DefId;
+use rustc_infer::infer::InferCtxt;
+use rustc_infer::traits::{Obligation, ObligationCause, TraitObligation};
+use rustc_span::DUMMY_SP;
+
+use crate::traits::ObligationCtxt;
+
+pub fn recompute_applicable_impls<'tcx>(
+    infcx: &InferCtxt<'tcx>,
+    obligation: &TraitObligation<'tcx>,
+) -> Vec<DefId> {
+    let tcx = infcx.tcx;
+    let param_env = obligation.param_env;
+    let dummy_cause = ObligationCause::dummy();
+    let impl_may_apply = |impl_def_id| {
+        let ocx = ObligationCtxt::new_in_snapshot(infcx);
+        let placeholder_obligation =
+            infcx.replace_bound_vars_with_placeholders(obligation.predicate);
+        let obligation_trait_ref =
+            ocx.normalize(dummy_cause.clone(), param_env, placeholder_obligation.trait_ref);
+
+        let impl_substs = infcx.fresh_substs_for_item(DUMMY_SP, impl_def_id);
+        let impl_trait_ref = tcx.bound_impl_trait_ref(impl_def_id).unwrap().subst(tcx, impl_substs);
+        let impl_trait_ref = ocx.normalize(ObligationCause::dummy(), param_env, impl_trait_ref);
+
+        if let Err(_) = ocx.eq(&dummy_cause, param_env, obligation_trait_ref, impl_trait_ref) {
+            return false;
+        }
+
+        let impl_predicates = tcx.predicates_of(impl_def_id).instantiate(tcx, impl_substs);
+        ocx.register_obligations(
+            impl_predicates
+                .predicates
+                .iter()
+                .map(|&predicate| Obligation::new(dummy_cause.clone(), param_env, predicate)),
+        );
+
+        ocx.select_where_possible().is_empty()
+    };
+
+    let mut impls = Vec::new();
+    tcx.for_each_relevant_impl(
+        obligation.predicate.def_id(),
+        obligation.predicate.skip_binder().trait_ref.self_ty(),
+        |impl_def_id| {
+            if infcx.probe(move |_snapshot| impl_may_apply(impl_def_id)) {
+                impls.push(impl_def_id)
+            }
+        },
+    );
+    impls
+}
diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs
index 1217d264a9c1..41b252a82651 100644
--- a/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs
+++ b/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs
@@ -1,17 +1,22 @@
+mod ambiguity;
 pub mod on_unimplemented;
 pub mod suggestions;
 
 use super::{
-    FulfillmentContext, FulfillmentError, FulfillmentErrorCode, MismatchedProjectionTypes,
-    Obligation, ObligationCause, ObligationCauseCode, OnUnimplementedDirective,
-    OnUnimplementedNote, OutputTypeParameterMismatch, Overflow, PredicateObligation,
+    FulfillmentError, FulfillmentErrorCode, MismatchedProjectionTypes, Obligation, ObligationCause,
+    ObligationCauseCode, OutputTypeParameterMismatch, Overflow, PredicateObligation,
     SelectionContext, SelectionError, TraitNotObjectSafe,
 };
-
 use crate::infer::error_reporting::{TyCategory, TypeAnnotationNeeded as ErrorCode};
 use crate::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKind};
 use crate::infer::{self, InferCtxt, TyCtxtInferExt};
-use rustc_data_structures::fx::FxHashMap;
+use crate::traits::engine::TraitEngineExt as _;
+use crate::traits::query::evaluate_obligation::InferCtxtExt as _;
+use crate::traits::query::normalize::AtExt as _;
+use crate::traits::specialize::to_pretty_impl_header;
+use on_unimplemented::OnUnimplementedNote;
+use on_unimplemented::TypeErrCtxtExt as _;
+use rustc_data_structures::fx::{FxHashMap, FxIndexMap};
 use rustc_errors::{
     pluralize, struct_span_err, Applicability, Diagnostic, DiagnosticBuilder, ErrorGuaranteed,
     MultiSpan, Style,
@@ -40,11 +45,6 @@ use rustc_span::{ExpnKind, Span, DUMMY_SP};
 use std::fmt;
 use std::iter;
 use std::ops::ControlFlow;
-
-use crate::traits::query::evaluate_obligation::InferCtxtExt as _;
-use crate::traits::query::normalize::AtExt as _;
-use crate::traits::specialize::to_pretty_impl_header;
-use on_unimplemented::TypeErrCtxtExt as _;
 use suggestions::TypeErrCtxtExt as _;
 
 pub use rustc_infer::traits::error_reporting::*;
@@ -101,7 +101,6 @@ pub trait TypeErrCtxtExt<'tcx> {
         &self,
         errors: &[FulfillmentError<'tcx>],
         body_id: Option<hir::BodyId>,
-        fallback_has_occurred: bool,
     ) -> ErrorGuaranteed;
 
     fn report_overflow_error<T>(
@@ -124,7 +123,6 @@ pub trait TypeErrCtxtExt<'tcx> {
         obligation: PredicateObligation<'tcx>,
         root_obligation: &PredicateObligation<'tcx>,
         error: &SelectionError<'tcx>,
-        fallback_has_occurred: bool,
     );
 }
 
@@ -355,7 +353,7 @@ impl<'tcx> InferCtxtExt<'tcx> for InferCtxt<'tcx> {
                     })
                     .to_predicate(self.tcx),
                 );
-                let mut fulfill_cx = FulfillmentContext::new_in_snapshot();
+                let mut fulfill_cx = <dyn TraitEngine<'tcx>>::new_in_snapshot(self.tcx);
                 fulfill_cx.register_predicate_obligation(self, obligation);
                 if fulfill_cx.select_all_or_error(self).is_empty() {
                     return Ok((
@@ -375,7 +373,6 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
         &self,
         errors: &[FulfillmentError<'tcx>],
         body_id: Option<hir::BodyId>,
-        fallback_has_occurred: bool,
     ) -> ErrorGuaranteed {
         #[derive(Debug)]
         struct ErrorDescriptor<'tcx> {
@@ -383,7 +380,7 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
             index: Option<usize>, // None if this is an old error
         }
 
-        let mut error_map: FxHashMap<_, Vec<_>> = self
+        let mut error_map: FxIndexMap<_, Vec<_>> = self
             .reported_trait_errors
             .borrow()
             .iter()
@@ -452,7 +449,7 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
 
         for (error, suppressed) in iter::zip(errors, is_suppressed) {
             if !suppressed {
-                self.report_fulfillment_error(error, body_id, fallback_has_occurred);
+                self.report_fulfillment_error(error, body_id);
             }
         }
 
@@ -534,22 +531,12 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
         mut obligation: PredicateObligation<'tcx>,
         root_obligation: &PredicateObligation<'tcx>,
         error: &SelectionError<'tcx>,
-        fallback_has_occurred: bool,
     ) {
         self.set_tainted_by_errors();
         let tcx = self.tcx;
         let mut span = obligation.cause.span;
 
         let mut err = match *error {
-            SelectionError::Ambiguous(ref impls) => {
-                let mut err = self.tcx.sess.struct_span_err(
-                    obligation.cause.span,
-                    &format!("multiple applicable `impl`s for `{}`", obligation.predicate),
-                );
-                self.annotate_source_of_ambiguity(&mut err, impls, obligation.predicate);
-                err.emit();
-                return;
-            }
             SelectionError::Unimplemented => {
                 // If this obligation was generated as a result of well-formedness checking, see if we
                 // can get a better error message by performing HIR-based well-formedness checking.
@@ -663,40 +650,32 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                                 ))
                         );
 
-                        if is_try_conversion {
-                            let none_error = self
-                                .tcx
-                                .get_diagnostic_item(sym::none_error)
-                                .map(|def_id| tcx.type_of(def_id));
-                            let should_convert_option_to_result =
-                                Some(trait_ref.skip_binder().substs.type_at(1)) == none_error;
-                            let should_convert_result_to_option =
-                                Some(trait_ref.self_ty().skip_binder()) == none_error;
-                            if should_convert_option_to_result {
-                                err.span_suggestion_verbose(
-                                    span.shrink_to_lo(),
-                                    "consider converting the `Option<T>` into a `Result<T, _>` \
-                                     using `Option::ok_or` or `Option::ok_or_else`",
-                                    ".ok_or_else(|| /* error value */)",
-                                    Applicability::HasPlaceholders,
-                                );
-                            } else if should_convert_result_to_option {
-                                err.span_suggestion_verbose(
-                                    span.shrink_to_lo(),
-                                    "consider converting the `Result<T, _>` into an `Option<T>` \
-                                     using `Result::ok`",
-                                    ".ok()",
-                                    Applicability::MachineApplicable,
-                                );
-                            }
-                            if let Some(ret_span) = self.return_type_span(&obligation) {
-                                err.span_label(
-                                    ret_span,
-                                    &format!(
-                                        "expected `{}` because of this",
-                                        trait_ref.skip_binder().self_ty()
-                                    ),
-                                );
+                        if is_try_conversion && let Some(ret_span) = self.return_type_span(&obligation) {
+                            err.span_label(
+                                ret_span,
+                                &format!(
+                                    "expected `{}` because of this",
+                                    trait_ref.skip_binder().self_ty()
+                                ),
+                            );
+                        }
+
+                        if Some(trait_ref.def_id()) == tcx.lang_items().tuple_trait() {
+                            match obligation.cause.code().peel_derives() {
+                                ObligationCauseCode::RustCall => {
+                                    err.set_primary_message("functions with the \"rust-call\" ABI must take a single non-self tuple argument");
+                                }
+                                ObligationCauseCode::BindingObligation(def_id, _)
+                                | ObligationCauseCode::ItemObligation(def_id)
+                                    if ty::ClosureKind::from_def_id(tcx, *def_id).is_some() =>
+                                {
+                                    err.code(rustc_errors::error_code!(E0059));
+                                    err.set_primary_message(format!(
+                                        "type parameter to bare `{}` trait must be a tuple",
+                                        tcx.def_path_str(*def_id)
+                                    ));
+                                }
+                                _ => {}
                             }
                         }
 
@@ -848,12 +827,8 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                             );
                         }
 
-                        let is_fn_trait = [
-                            self.tcx.lang_items().fn_trait(),
-                            self.tcx.lang_items().fn_mut_trait(),
-                            self.tcx.lang_items().fn_once_trait(),
-                        ]
-                        .contains(&Some(trait_ref.def_id()));
+                        let is_fn_trait =
+                            ty::ClosureKind::from_def_id(tcx, trait_ref.def_id()).is_some();
                         let is_target_feature_fn = if let ty::FnDef(def_id, _) =
                             *trait_ref.skip_binder().self_ty().kind()
                         {
@@ -974,7 +949,7 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                                 // useful for less general traits.
                                 if peeled
                                     && !self.tcx.trait_is_auto(def_id)
-                                    && !self.tcx.lang_items().items().contains(&Some(def_id))
+                                    && !self.tcx.lang_items().iter().any(|(_, id)| id == def_id)
                                 {
                                     let trait_ref = trait_pred.to_poly_trait_ref();
                                     let impl_candidates =
@@ -1000,7 +975,7 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                         // variable that used to fallback to `()` now falling back to `!`. Issue a
                         // note informing about the change in behaviour.
                         if trait_predicate.skip_binder().self_ty().is_never()
-                            && fallback_has_occurred
+                            && self.fallback_has_occurred
                         {
                             let predicate = trait_predicate.map_bound(|mut trait_pred| {
                                 trait_pred.trait_ref.substs = self.tcx.mk_substs_trait(
@@ -1366,7 +1341,6 @@ trait InferCtxtPrivExt<'tcx> {
         &self,
         error: &FulfillmentError<'tcx>,
         body_id: Option<hir::BodyId>,
-        fallback_has_occurred: bool,
     );
 
     fn report_projection_error(
@@ -1516,7 +1490,6 @@ impl<'tcx> InferCtxtPrivExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
         &self,
         error: &FulfillmentError<'tcx>,
         body_id: Option<hir::BodyId>,
-        fallback_has_occurred: bool,
     ) {
         match error.code {
             FulfillmentErrorCode::CodeSelectionError(ref selection_error) => {
@@ -1524,7 +1497,6 @@ impl<'tcx> InferCtxtPrivExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                     error.obligation.clone(),
                     &error.root_obligation,
                     selection_error,
-                    fallback_has_occurred,
                 );
             }
             FulfillmentErrorCode::CodeProjectionError(ref e) => {
@@ -1898,7 +1870,7 @@ impl<'tcx> InferCtxtPrivExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
         let def_id = trait_ref.def_id();
         if impl_candidates.is_empty() {
             if self.tcx.trait_is_auto(def_id)
-                || self.tcx.lang_items().items().contains(&Some(def_id))
+                || self.tcx.lang_items().iter().any(|(_, id)| id == def_id)
                 || self.tcx.get_diagnostic_name(def_id).is_some()
             {
                 // Mentioning implementers of `Copy`, `Debug` and friends is not useful.
@@ -2138,12 +2110,25 @@ impl<'tcx> InferCtxtPrivExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                     crate::traits::TraitQueryMode::Standard,
                 );
                 match selcx.select_from_obligation(&obligation) {
-                    Err(SelectionError::Ambiguous(impls)) if impls.len() > 1 => {
-                        self.annotate_source_of_ambiguity(&mut err, &impls, predicate);
+                    Ok(None) => {
+                        let impls = ambiguity::recompute_applicable_impls(self.infcx, &obligation);
+                        let has_non_region_infer =
+                            trait_ref.skip_binder().substs.types().any(|t| !t.is_ty_infer());
+                        // It doesn't make sense to talk about applicable impls if there are more
+                        // than a handful of them.
+                        if impls.len() > 1 && impls.len() < 5 && has_non_region_infer {
+                            self.annotate_source_of_ambiguity(&mut err, &impls, predicate);
+                        } else {
+                            if self.is_tainted_by_errors() {
+                                err.delay_as_bug();
+                                return;
+                            }
+                            err.note(&format!("cannot satisfy `{}`", predicate));
+                        }
                     }
                     _ => {
                         if self.is_tainted_by_errors() {
-                            err.cancel();
+                            err.delay_as_bug();
                             return;
                         }
                         err.note(&format!("cannot satisfy `{}`", predicate));
@@ -2435,7 +2420,6 @@ impl<'tcx> InferCtxtPrivExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                 }
             }
         }
-        let msg = format!("multiple `impl`s satisfying `{}` found", predicate);
         let mut crate_names: Vec<_> = crates.iter().map(|n| format!("`{}`", n)).collect();
         crate_names.sort();
         crate_names.dedup();
@@ -2456,13 +2440,9 @@ impl<'tcx> InferCtxtPrivExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
             err.downgrade_to_delayed_bug();
             return;
         }
-        let post = if post.len() > 4 {
-            format!(
-                ":\n{}\nand {} more",
-                post.iter().map(|p| format!("- {}", p)).take(4).collect::<Vec<_>>().join("\n"),
-                post.len() - 4,
-            )
-        } else if post.len() > 1 || (post.len() == 1 && post[0].contains('\n')) {
+
+        let msg = format!("multiple `impl`s satisfying `{}` found", predicate);
+        let post = if post.len() > 1 || (post.len() == 1 && post[0].contains('\n')) {
             format!(":\n{}", post.iter().map(|p| format!("- {}", p)).collect::<Vec<_>>().join("\n"),)
         } else if post.len() == 1 {
             format!(": `{}`", post[0])
diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/on_unimplemented.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/on_unimplemented.rs
index 5eef54c6330d..82f0440b3078 100644
--- a/compiler/rustc_trait_selection/src/traits/error_reporting/on_unimplemented.rs
+++ b/compiler/rustc_trait_selection/src/traits/error_reporting/on_unimplemented.rs
@@ -1,14 +1,22 @@
-use super::{
-    ObligationCauseCode, OnUnimplementedDirective, OnUnimplementedNote, PredicateObligation,
-};
+use super::{ObligationCauseCode, PredicateObligation};
 use crate::infer::error_reporting::TypeErrCtxt;
+use rustc_ast::{MetaItem, NestedMetaItem};
+use rustc_attr as attr;
+use rustc_data_structures::fx::FxHashMap;
+use rustc_errors::{struct_span_err, ErrorGuaranteed};
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
 use rustc_middle::ty::SubstsRef;
-use rustc_middle::ty::{self, GenericParamDefKind};
-use rustc_span::symbol::sym;
+use rustc_middle::ty::{self, GenericParamDefKind, TyCtxt};
+use rustc_parse_format::{ParseMode, Parser, Piece, Position};
+use rustc_span::symbol::{kw, sym, Symbol};
+use rustc_span::{Span, DUMMY_SP};
 use std::iter;
 
+use crate::errors::{
+    EmptyOnClauseInOnUnimplemented, InvalidOnClauseInOnUnimplemented, NoValueInOnUnimplemented,
+};
+
 use super::InferCtxtPrivExt;
 
 pub trait TypeErrCtxtExt<'tcx> {
@@ -276,3 +284,383 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
         }
     }
 }
+
+#[derive(Clone, Debug)]
+pub struct OnUnimplementedFormatString(Symbol);
+
+#[derive(Debug)]
+pub struct OnUnimplementedDirective {
+    pub condition: Option<MetaItem>,
+    pub subcommands: Vec<OnUnimplementedDirective>,
+    pub message: Option<OnUnimplementedFormatString>,
+    pub label: Option<OnUnimplementedFormatString>,
+    pub note: Option<OnUnimplementedFormatString>,
+    pub parent_label: Option<OnUnimplementedFormatString>,
+    pub append_const_msg: Option<Option<Symbol>>,
+}
+
+/// For the `#[rustc_on_unimplemented]` attribute
+#[derive(Default)]
+pub struct OnUnimplementedNote {
+    pub message: Option<String>,
+    pub label: Option<String>,
+    pub note: Option<String>,
+    pub parent_label: Option<String>,
+    /// Append a message for `~const Trait` errors. `None` means not requested and
+    /// should fallback to a generic message, `Some(None)` suggests using the default
+    /// appended message, `Some(Some(s))` suggests use the `s` message instead of the
+    /// default one..
+    pub append_const_msg: Option<Option<Symbol>>,
+}
+
+impl<'tcx> OnUnimplementedDirective {
+    fn parse(
+        tcx: TyCtxt<'tcx>,
+        item_def_id: DefId,
+        items: &[NestedMetaItem],
+        span: Span,
+        is_root: bool,
+    ) -> Result<Self, ErrorGuaranteed> {
+        let mut errored = None;
+        let mut item_iter = items.iter();
+
+        let parse_value = |value_str| {
+            OnUnimplementedFormatString::try_parse(tcx, item_def_id, value_str, span).map(Some)
+        };
+
+        let condition = if is_root {
+            None
+        } else {
+            let cond = item_iter
+                .next()
+                .ok_or_else(|| tcx.sess.emit_err(EmptyOnClauseInOnUnimplemented { span }))?
+                .meta_item()
+                .ok_or_else(|| tcx.sess.emit_err(InvalidOnClauseInOnUnimplemented { span }))?;
+            attr::eval_condition(cond, &tcx.sess.parse_sess, Some(tcx.features()), &mut |cfg| {
+                if let Some(value) = cfg.value && let Err(guar) = parse_value(value) {
+                    errored = Some(guar);
+                }
+                true
+            });
+            Some(cond.clone())
+        };
+
+        let mut message = None;
+        let mut label = None;
+        let mut note = None;
+        let mut parent_label = None;
+        let mut subcommands = vec![];
+        let mut append_const_msg = None;
+
+        for item in item_iter {
+            if item.has_name(sym::message) && message.is_none() {
+                if let Some(message_) = item.value_str() {
+                    message = parse_value(message_)?;
+                    continue;
+                }
+            } else if item.has_name(sym::label) && label.is_none() {
+                if let Some(label_) = item.value_str() {
+                    label = parse_value(label_)?;
+                    continue;
+                }
+            } else if item.has_name(sym::note) && note.is_none() {
+                if let Some(note_) = item.value_str() {
+                    note = parse_value(note_)?;
+                    continue;
+                }
+            } else if item.has_name(sym::parent_label) && parent_label.is_none() {
+                if let Some(parent_label_) = item.value_str() {
+                    parent_label = parse_value(parent_label_)?;
+                    continue;
+                }
+            } else if item.has_name(sym::on)
+                && is_root
+                && message.is_none()
+                && label.is_none()
+                && note.is_none()
+            {
+                if let Some(items) = item.meta_item_list() {
+                    match Self::parse(tcx, item_def_id, &items, item.span(), false) {
+                        Ok(subcommand) => subcommands.push(subcommand),
+                        Err(reported) => errored = Some(reported),
+                    };
+                    continue;
+                }
+            } else if item.has_name(sym::append_const_msg) && append_const_msg.is_none() {
+                if let Some(msg) = item.value_str() {
+                    append_const_msg = Some(Some(msg));
+                    continue;
+                } else if item.is_word() {
+                    append_const_msg = Some(None);
+                    continue;
+                }
+            }
+
+            // nothing found
+            tcx.sess.emit_err(NoValueInOnUnimplemented { span: item.span() });
+        }
+
+        if let Some(reported) = errored {
+            Err(reported)
+        } else {
+            Ok(OnUnimplementedDirective {
+                condition,
+                subcommands,
+                message,
+                label,
+                note,
+                parent_label,
+                append_const_msg,
+            })
+        }
+    }
+
+    pub fn of_item(tcx: TyCtxt<'tcx>, item_def_id: DefId) -> Result<Option<Self>, ErrorGuaranteed> {
+        let Some(attr) = tcx.get_attr(item_def_id, sym::rustc_on_unimplemented) else {
+            return Ok(None);
+        };
+
+        let result = if let Some(items) = attr.meta_item_list() {
+            Self::parse(tcx, item_def_id, &items, attr.span, true).map(Some)
+        } else if let Some(value) = attr.value_str() {
+            Ok(Some(OnUnimplementedDirective {
+                condition: None,
+                message: None,
+                subcommands: vec![],
+                label: Some(OnUnimplementedFormatString::try_parse(
+                    tcx,
+                    item_def_id,
+                    value,
+                    attr.span,
+                )?),
+                note: None,
+                parent_label: None,
+                append_const_msg: None,
+            }))
+        } else {
+            let reported =
+                tcx.sess.delay_span_bug(DUMMY_SP, "of_item: neither meta_item_list nor value_str");
+            return Err(reported);
+        };
+        debug!("of_item({:?}) = {:?}", item_def_id, result);
+        result
+    }
+
+    pub fn evaluate(
+        &self,
+        tcx: TyCtxt<'tcx>,
+        trait_ref: ty::TraitRef<'tcx>,
+        options: &[(Symbol, Option<String>)],
+    ) -> OnUnimplementedNote {
+        let mut message = None;
+        let mut label = None;
+        let mut note = None;
+        let mut parent_label = None;
+        let mut append_const_msg = None;
+        info!("evaluate({:?}, trait_ref={:?}, options={:?})", self, trait_ref, options);
+
+        let options_map: FxHashMap<Symbol, String> =
+            options.iter().filter_map(|(k, v)| v.as_ref().map(|v| (*k, v.to_owned()))).collect();
+
+        for command in self.subcommands.iter().chain(Some(self)).rev() {
+            if let Some(ref condition) = command.condition && !attr::eval_condition(
+                condition,
+                &tcx.sess.parse_sess,
+                Some(tcx.features()),
+                &mut |cfg| {
+                    let value = cfg.value.map(|v| {
+                        OnUnimplementedFormatString(v).format(tcx, trait_ref, &options_map)
+                    });
+
+                    options.contains(&(cfg.name, value))
+                },
+            ) {
+                debug!("evaluate: skipping {:?} due to condition", command);
+                continue;
+            }
+            debug!("evaluate: {:?} succeeded", command);
+            if let Some(ref message_) = command.message {
+                message = Some(message_.clone());
+            }
+
+            if let Some(ref label_) = command.label {
+                label = Some(label_.clone());
+            }
+
+            if let Some(ref note_) = command.note {
+                note = Some(note_.clone());
+            }
+
+            if let Some(ref parent_label_) = command.parent_label {
+                parent_label = Some(parent_label_.clone());
+            }
+
+            append_const_msg = command.append_const_msg;
+        }
+
+        OnUnimplementedNote {
+            label: label.map(|l| l.format(tcx, trait_ref, &options_map)),
+            message: message.map(|m| m.format(tcx, trait_ref, &options_map)),
+            note: note.map(|n| n.format(tcx, trait_ref, &options_map)),
+            parent_label: parent_label.map(|e_s| e_s.format(tcx, trait_ref, &options_map)),
+            append_const_msg,
+        }
+    }
+}
+
+impl<'tcx> OnUnimplementedFormatString {
+    fn try_parse(
+        tcx: TyCtxt<'tcx>,
+        item_def_id: DefId,
+        from: Symbol,
+        err_sp: Span,
+    ) -> Result<Self, ErrorGuaranteed> {
+        let result = OnUnimplementedFormatString(from);
+        result.verify(tcx, item_def_id, err_sp)?;
+        Ok(result)
+    }
+
+    fn verify(
+        &self,
+        tcx: TyCtxt<'tcx>,
+        item_def_id: DefId,
+        span: Span,
+    ) -> Result<(), ErrorGuaranteed> {
+        let trait_def_id = if tcx.is_trait(item_def_id) {
+            item_def_id
+        } else {
+            tcx.trait_id_of_impl(item_def_id)
+                .expect("expected `on_unimplemented` to correspond to a trait")
+        };
+        let trait_name = tcx.item_name(trait_def_id);
+        let generics = tcx.generics_of(item_def_id);
+        let s = self.0.as_str();
+        let parser = Parser::new(s, None, None, false, ParseMode::Format);
+        let mut result = Ok(());
+        for token in parser {
+            match token {
+                Piece::String(_) => (), // Normal string, no need to check it
+                Piece::NextArgument(a) => match a.position {
+                    Position::ArgumentNamed(s) => {
+                        match Symbol::intern(s) {
+                            // `{Self}` is allowed
+                            kw::SelfUpper => (),
+                            // `{ThisTraitsName}` is allowed
+                            s if s == trait_name => (),
+                            // `{from_method}` is allowed
+                            sym::from_method => (),
+                            // `{from_desugaring}` is allowed
+                            sym::from_desugaring => (),
+                            // `{ItemContext}` is allowed
+                            sym::ItemContext => (),
+                            // `{integral}` and `{integer}` and `{float}` are allowed
+                            sym::integral | sym::integer_ | sym::float => (),
+                            // So is `{A}` if A is a type parameter
+                            s => match generics.params.iter().find(|param| param.name == s) {
+                                Some(_) => (),
+                                None => {
+                                    let reported = struct_span_err!(
+                                        tcx.sess,
+                                        span,
+                                        E0230,
+                                        "there is no parameter `{}` on {}",
+                                        s,
+                                        if trait_def_id == item_def_id {
+                                            format!("trait `{}`", trait_name)
+                                        } else {
+                                            "impl".to_string()
+                                        }
+                                    )
+                                    .emit();
+                                    result = Err(reported);
+                                }
+                            },
+                        }
+                    }
+                    // `{:1}` and `{}` are not to be used
+                    Position::ArgumentIs(..) | Position::ArgumentImplicitlyIs(_) => {
+                        let reported = struct_span_err!(
+                            tcx.sess,
+                            span,
+                            E0231,
+                            "only named substitution parameters are allowed"
+                        )
+                        .emit();
+                        result = Err(reported);
+                    }
+                },
+            }
+        }
+
+        result
+    }
+
+    pub fn format(
+        &self,
+        tcx: TyCtxt<'tcx>,
+        trait_ref: ty::TraitRef<'tcx>,
+        options: &FxHashMap<Symbol, String>,
+    ) -> String {
+        let name = tcx.item_name(trait_ref.def_id);
+        let trait_str = tcx.def_path_str(trait_ref.def_id);
+        let generics = tcx.generics_of(trait_ref.def_id);
+        let generic_map = generics
+            .params
+            .iter()
+            .filter_map(|param| {
+                let value = match param.kind {
+                    GenericParamDefKind::Type { .. } | GenericParamDefKind::Const { .. } => {
+                        trait_ref.substs[param.index as usize].to_string()
+                    }
+                    GenericParamDefKind::Lifetime => return None,
+                };
+                let name = param.name;
+                Some((name, value))
+            })
+            .collect::<FxHashMap<Symbol, String>>();
+        let empty_string = String::new();
+
+        let s = self.0.as_str();
+        let parser = Parser::new(s, None, None, false, ParseMode::Format);
+        let item_context = (options.get(&sym::ItemContext)).unwrap_or(&empty_string);
+        parser
+            .map(|p| match p {
+                Piece::String(s) => s,
+                Piece::NextArgument(a) => match a.position {
+                    Position::ArgumentNamed(s) => {
+                        let s = Symbol::intern(s);
+                        match generic_map.get(&s) {
+                            Some(val) => val,
+                            None if s == name => &trait_str,
+                            None => {
+                                if let Some(val) = options.get(&s) {
+                                    val
+                                } else if s == sym::from_desugaring || s == sym::from_method {
+                                    // don't break messages using these two arguments incorrectly
+                                    &empty_string
+                                } else if s == sym::ItemContext {
+                                    &item_context
+                                } else if s == sym::integral {
+                                    "{integral}"
+                                } else if s == sym::integer_ {
+                                    "{integer}"
+                                } else if s == sym::float {
+                                    "{float}"
+                                } else {
+                                    bug!(
+                                        "broken on_unimplemented {:?} for {:?}: \
+                                      no argument matching {:?}",
+                                        self.0,
+                                        trait_ref,
+                                        s
+                                    )
+                                }
+                            }
+                        }
+                    }
+                    _ => bug!("broken on_unimplemented {:?} - bad format arg", self.0),
+                },
+            })
+            .collect()
+    }
+}
diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
index 8c41d9d240c7..84daaf97ecfa 100644
--- a/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
+++ b/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
@@ -44,7 +44,7 @@ use rustc_middle::ty::print::with_no_trimmed_paths;
 #[derive(Debug)]
 pub enum GeneratorInteriorOrUpvar {
     // span of interior type
-    Interior(Span),
+    Interior(Span, Option<(Option<Span>, Span, Option<hir::HirId>, Option<Span>)>),
     // span of upvar
     Upvar(Span),
 }
@@ -283,7 +283,6 @@ pub trait TypeErrCtxtExt<'tcx> {
         &self,
         err: &mut Diagnostic,
         interior_or_upvar_span: GeneratorInteriorOrUpvar,
-        interior_extra_info: Option<(Option<Span>, Span, Option<hir::HirId>, Option<Span>)>,
         is_async: bool,
         outer_generator: Option<DefId>,
         trait_pred: ty::TraitPredicate<'tcx>,
@@ -714,7 +713,6 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                     obligation.cause.body_id,
                     span,
                     base_ty,
-                    span,
                 );
                 if let Some(steps) = autoderef.find_map(|(ty, steps)| {
                     // Re-add the `&`
@@ -1019,7 +1017,7 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
         let mut never_suggest_borrow: Vec<_> =
             [LangItem::Copy, LangItem::Clone, LangItem::Unpin, LangItem::Sized]
                 .iter()
-                .filter_map(|lang_item| self.tcx.lang_items().require(*lang_item).ok())
+                .filter_map(|lang_item| self.tcx.lang_items().get(*lang_item))
                 .collect();
 
         if let Some(def_id) = self.tcx.get_diagnostic_item(sym::Send) {
@@ -1117,7 +1115,7 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                         err.span_suggestions(
                             span.shrink_to_lo(),
                             "consider borrowing here",
-                            ["&".to_string(), "&mut ".to_string()].into_iter(),
+                            ["&".to_string(), "&mut ".to_string()],
                             Applicability::MaybeIncorrect,
                         );
                     } else {
@@ -2004,17 +2002,11 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
             .as_local()
             .and_then(|def_id| hir.maybe_body_owned_by(def_id))
             .map(|body_id| hir.body(body_id));
-        let is_async = match generator_did.as_local() {
-            Some(_) => generator_body
-                .and_then(|body| body.generator_kind())
-                .map(|generator_kind| matches!(generator_kind, hir::GeneratorKind::Async(..)))
-                .unwrap_or(false),
-            None => self
-                .tcx
-                .generator_kind(generator_did)
-                .map(|generator_kind| matches!(generator_kind, hir::GeneratorKind::Async(..)))
-                .unwrap_or(false),
-        };
+        let is_async = self
+            .tcx
+            .generator_kind(generator_did)
+            .map(|generator_kind| matches!(generator_kind, hir::GeneratorKind::Async(..)))
+            .unwrap_or(false);
         let mut visitor = AwaitsVisitor::default();
         if let Some(body) = generator_body {
             visitor.visit_body(body);
@@ -2044,61 +2036,60 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
             eq
         };
 
-        let mut interior_or_upvar_span = None;
-        let mut interior_extra_info = None;
-
         // Get the typeck results from the infcx if the generator is the function we are currently
         // type-checking; otherwise, get them by performing a query.  This is needed to avoid
         // cycles. If we can't use resolved types because the generator comes from another crate,
         // we still provide a targeted error but without all the relevant spans.
-        let generator_data: Option<GeneratorData<'tcx, '_>> = match &self.typeck_results {
-            Some(t) if t.hir_owner.to_def_id() == generator_did_root => {
-                Some(GeneratorData::Local(&t))
-            }
+        let generator_data = match &self.typeck_results {
+            Some(t) if t.hir_owner.to_def_id() == generator_did_root => GeneratorData::Local(&t),
             _ if generator_did.is_local() => {
-                Some(GeneratorData::Local(self.tcx.typeck(generator_did.expect_local())))
+                GeneratorData::Local(self.tcx.typeck(generator_did.expect_local()))
             }
-            _ => self
-                .tcx
-                .generator_diagnostic_data(generator_did)
-                .as_ref()
-                .map(|generator_diag_data| GeneratorData::Foreign(generator_diag_data)),
+            _ if let Some(generator_diag_data) = self.tcx.generator_diagnostic_data(generator_did) => {
+                GeneratorData::Foreign(generator_diag_data)
+            }
+            _ => return false,
         };
 
-        if let Some(generator_data) = generator_data.as_ref() {
-            interior_or_upvar_span =
-                generator_data.try_get_upvar_span(&self, generator_did, ty_matches);
+        let mut interior_or_upvar_span = None;
 
-            // The generator interior types share the same binders
-            if let Some(cause) =
-                generator_data.get_generator_interior_types().skip_binder().iter().find(
-                    |ty::GeneratorInteriorTypeCause { ty, .. }| {
-                        ty_matches(generator_data.get_generator_interior_types().rebind(*ty))
-                    },
-                )
-            {
-                let from_awaited_ty = generator_data.get_from_await_ty(visitor, hir, ty_matches);
-                let ty::GeneratorInteriorTypeCause { span, scope_span, yield_span, expr, .. } =
-                    cause;
+        let from_awaited_ty = generator_data.get_from_await_ty(visitor, hir, ty_matches);
+        debug!(?from_awaited_ty);
 
-                interior_or_upvar_span = Some(GeneratorInteriorOrUpvar::Interior(*span));
-                interior_extra_info = Some((*scope_span, *yield_span, *expr, from_awaited_ty));
-            }
+        // The generator interior types share the same binders
+        if let Some(cause) =
+            generator_data.get_generator_interior_types().skip_binder().iter().find(
+                |ty::GeneratorInteriorTypeCause { ty, .. }| {
+                    ty_matches(generator_data.get_generator_interior_types().rebind(*ty))
+                },
+            )
+        {
+            let ty::GeneratorInteriorTypeCause { span, scope_span, yield_span, expr, .. } = cause;
 
-            if interior_or_upvar_span.is_none() && generator_data.is_foreign() {
-                interior_or_upvar_span = Some(GeneratorInteriorOrUpvar::Interior(span));
-            }
+            interior_or_upvar_span = Some(GeneratorInteriorOrUpvar::Interior(
+                *span,
+                Some((*scope_span, *yield_span, *expr, from_awaited_ty)),
+            ));
         }
 
+        if interior_or_upvar_span.is_none() {
+            interior_or_upvar_span =
+                generator_data.try_get_upvar_span(&self, generator_did, ty_matches);
+        }
+
+        if interior_or_upvar_span.is_none() && generator_data.is_foreign() {
+            interior_or_upvar_span = Some(GeneratorInteriorOrUpvar::Interior(span, None));
+        }
+
+        debug!(?interior_or_upvar_span);
         if let Some(interior_or_upvar_span) = interior_or_upvar_span {
-            let typeck_results = generator_data.and_then(|generator_data| match generator_data {
+            let typeck_results = match generator_data {
                 GeneratorData::Local(typeck_results) => Some(typeck_results),
                 GeneratorData::Foreign(_) => None,
-            });
+            };
             self.note_obligation_cause_for_async_await(
                 err,
                 interior_or_upvar_span,
-                interior_extra_info,
                 is_async,
                 outer_generator,
                 trait_ref,
@@ -2120,7 +2111,6 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
         &self,
         err: &mut Diagnostic,
         interior_or_upvar_span: GeneratorInteriorOrUpvar,
-        interior_extra_info: Option<(Option<Span>, Span, Option<hir::HirId>, Option<Span>)>,
         is_async: bool,
         outer_generator: Option<DefId>,
         trait_pred: ty::TraitPredicate<'tcx>,
@@ -2242,7 +2232,7 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
             }
         };
         match interior_or_upvar_span {
-            GeneratorInteriorOrUpvar::Interior(interior_span) => {
+            GeneratorInteriorOrUpvar::Interior(interior_span, interior_extra_info) => {
                 if let Some((scope_span, yield_span, expr, from_awaited_ty)) = interior_extra_info {
                     if let Some(await_span) = from_awaited_ty {
                         // The type causing this obligation is one being awaited at await_span.
@@ -2407,7 +2397,8 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
             | ObligationCauseCode::CheckAssociatedTypeBounds { .. }
             | ObligationCauseCode::LetElse
             | ObligationCauseCode::BinOp { .. }
-            | ObligationCauseCode::AscribeUserTypeProvePredicate(..) => {}
+            | ObligationCauseCode::AscribeUserTypeProvePredicate(..)
+            | ObligationCauseCode::RustCall => {}
             ObligationCauseCode::SliceOrArrayElem => {
                 err.note("slice and array elements must have `Sized` type");
             }
@@ -2445,12 +2436,12 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                             (Ok(l), Ok(r)) => l.line == r.line,
                             _ => true,
                         };
-                    if !ident.span.overlaps(span) && !same_line {
+                    if !ident.span.is_dummy() && !ident.span.overlaps(span) && !same_line {
                         multispan.push_span_label(ident.span, "required by a bound in this");
                     }
                 }
                 let descr = format!("required by a bound in `{}`", item_name);
-                if span != DUMMY_SP {
+                if !span.is_dummy() {
                     let msg = format!("required by this bound in `{}`", item_name);
                     multispan.push_span_label(span, msg);
                     err.span_note(multispan, &descr);
diff --git a/compiler/rustc_trait_selection/src/traits/fulfill.rs b/compiler/rustc_trait_selection/src/traits/fulfill.rs
index a417e1440b9e..b486c07f354b 100644
--- a/compiler/rustc_trait_selection/src/traits/fulfill.rs
+++ b/compiler/rustc_trait_selection/src/traits/fulfill.rs
@@ -85,7 +85,7 @@ static_assert_size!(PendingPredicateObligation<'_>, 72);
 
 impl<'a, 'tcx> FulfillmentContext<'tcx> {
     /// Creates a new fulfillment context.
-    pub fn new() -> FulfillmentContext<'tcx> {
+    pub(super) fn new() -> FulfillmentContext<'tcx> {
         FulfillmentContext {
             predicates: ObligationForest::new(),
             relationships: FxHashMap::default(),
@@ -93,7 +93,7 @@ impl<'a, 'tcx> FulfillmentContext<'tcx> {
         }
     }
 
-    pub fn new_in_snapshot() -> FulfillmentContext<'tcx> {
+    pub(super) fn new_in_snapshot() -> FulfillmentContext<'tcx> {
         FulfillmentContext {
             predicates: ObligationForest::new(),
             relationships: FxHashMap::default(),
diff --git a/compiler/rustc_trait_selection/src/traits/misc.rs b/compiler/rustc_trait_selection/src/traits/misc.rs
index be603c609cb3..b6ded4ce5a39 100644
--- a/compiler/rustc_trait_selection/src/traits/misc.rs
+++ b/compiler/rustc_trait_selection/src/traits/misc.rs
@@ -70,7 +70,7 @@ pub fn can_type_implement_copy<'tcx>(
                     }
                 }
                 Err(errors) => {
-                    infcx.err_ctxt().report_fulfillment_errors(&errors, None, false);
+                    infcx.err_ctxt().report_fulfillment_errors(&errors, None);
                 }
             };
         }
diff --git a/compiler/rustc_trait_selection/src/traits/mod.rs b/compiler/rustc_trait_selection/src/traits/mod.rs
index 0bf54c096cd4..10e48610e3ab 100644
--- a/compiler/rustc_trait_selection/src/traits/mod.rs
+++ b/compiler/rustc_trait_selection/src/traits/mod.rs
@@ -12,7 +12,6 @@ pub mod error_reporting;
 mod fulfill;
 pub mod misc;
 mod object_safety;
-mod on_unimplemented;
 pub mod outlives_bounds;
 mod project;
 pub mod query;
@@ -58,7 +57,6 @@ pub use self::object_safety::astconv_object_safety_violations;
 pub use self::object_safety::is_vtable_safe_method;
 pub use self::object_safety::MethodViolationCode;
 pub use self::object_safety::ObjectSafetyViolation;
-pub use self::on_unimplemented::{OnUnimplementedDirective, OnUnimplementedNote};
 pub use self::project::{normalize, normalize_projection_type, normalize_to};
 pub use self::select::{EvaluationCache, SelectionCache, SelectionContext};
 pub use self::select::{EvaluationResult, IntercrateAmbiguityCause, OverflowError};
@@ -117,14 +115,12 @@ pub enum TraitQueryMode {
 }
 
 /// Creates predicate obligations from the generic bounds.
+#[instrument(level = "debug", skip(cause, param_env))]
 pub fn predicates_for_generics<'tcx>(
     cause: impl Fn(usize, Span) -> ObligationCause<'tcx>,
     param_env: ty::ParamEnv<'tcx>,
     generic_bounds: ty::InstantiatedPredicates<'tcx>,
 ) -> impl Iterator<Item = PredicateObligation<'tcx>> {
-    let generic_bounds = generic_bounds;
-    debug!("predicates_for_generics(generic_bounds={:?})", generic_bounds);
-
     std::iter::zip(generic_bounds.predicates, generic_bounds.spans).enumerate().map(
         move |(idx, (predicate, span))| Obligation {
             cause: cause(idx, span),
@@ -140,6 +136,7 @@ pub fn predicates_for_generics<'tcx>(
 /// `bound` or is not known to meet bound (note that this is
 /// conservative towards *no impl*, which is the opposite of the
 /// `evaluate` methods).
+#[instrument(level = "debug", skip(infcx, param_env, span), ret)]
 pub fn type_known_to_meet_bound_modulo_regions<'tcx>(
     infcx: &InferCtxt<'tcx>,
     param_env: ty::ParamEnv<'tcx>,
@@ -147,12 +144,6 @@ pub fn type_known_to_meet_bound_modulo_regions<'tcx>(
     def_id: DefId,
     span: Span,
 ) -> bool {
-    debug!(
-        "type_known_to_meet_bound_modulo_regions(ty={:?}, bound={:?})",
-        ty,
-        infcx.tcx.def_path_str(def_id)
-    );
-
     let trait_ref =
         ty::Binder::dummy(ty::TraitRef { def_id, substs: infcx.tcx.mk_substs_trait(ty, &[]) });
     let obligation = Obligation {
@@ -163,12 +154,7 @@ pub fn type_known_to_meet_bound_modulo_regions<'tcx>(
     };
 
     let result = infcx.predicate_must_hold_modulo_regions(&obligation);
-    debug!(
-        "type_known_to_meet_ty={:?} bound={} => {:?}",
-        ty,
-        infcx.tcx.def_path_str(def_id),
-        result
-    );
+    debug!(?result);
 
     if result && ty.has_non_region_infer() {
         // Because of inference "guessing", selection can sometimes claim
@@ -190,21 +176,9 @@ pub fn type_known_to_meet_bound_modulo_regions<'tcx>(
         // *definitively* show that it implements `Copy`. Otherwise,
         // assume it is move; linear is always ok.
         match &errors[..] {
-            [] => {
-                debug!(
-                    "type_known_to_meet_bound_modulo_regions: ty={:?} bound={} success",
-                    ty,
-                    infcx.tcx.def_path_str(def_id)
-                );
-                true
-            }
+            [] => true,
             errors => {
-                debug!(
-                    ?ty,
-                    bound = %infcx.tcx.def_path_str(def_id),
-                    ?errors,
-                    "type_known_to_meet_bound_modulo_regions"
-                );
+                debug!(?errors);
                 false
             }
         }
@@ -238,7 +212,7 @@ fn do_normalize_predicates<'tcx>(
     let predicates = match fully_normalize(&infcx, cause, elaborated_env, predicates) {
         Ok(predicates) => predicates,
         Err(errors) => {
-            let reported = infcx.err_ctxt().report_fulfillment_errors(&errors, None, false);
+            let reported = infcx.err_ctxt().report_fulfillment_errors(&errors, None);
             return Err(reported);
         }
     };
@@ -390,6 +364,7 @@ pub fn normalize_param_env_or_error<'tcx>(
 }
 
 /// Normalize a type and process all resulting obligations, returning any errors
+#[instrument(skip_all)]
 pub fn fully_normalize<'tcx, T>(
     infcx: &InferCtxt<'tcx>,
     cause: ObligationCause<'tcx>,
@@ -399,28 +374,18 @@ pub fn fully_normalize<'tcx, T>(
 where
     T: TypeFoldable<'tcx>,
 {
-    debug!("fully_normalize_with_fulfillcx(value={:?})", value);
-    let selcx = &mut SelectionContext::new(infcx);
-    let Normalized { value: normalized_value, obligations } =
-        project::normalize(selcx, param_env, cause, value);
-    debug!(
-        "fully_normalize: normalized_value={:?} obligations={:?}",
-        normalized_value, obligations
-    );
-
-    let mut fulfill_cx = FulfillmentContext::new();
-    for obligation in obligations {
-        fulfill_cx.register_predicate_obligation(infcx, obligation);
-    }
-
-    debug!("fully_normalize: select_all_or_error start");
-    let errors = fulfill_cx.select_all_or_error(infcx);
+    let ocx = ObligationCtxt::new(infcx);
+    debug!(?value);
+    let normalized_value = ocx.normalize(cause, param_env, value);
+    debug!(?normalized_value);
+    debug!("select_all_or_error start");
+    let errors = ocx.select_all_or_error();
     if !errors.is_empty() {
         return Err(errors);
     }
-    debug!("fully_normalize: select_all_or_error complete");
+    debug!("select_all_or_error complete");
     let resolved_value = infcx.resolve_vars_if_possible(normalized_value);
-    debug!("fully_normalize: resolved_value={:?}", resolved_value);
+    debug!(?resolved_value);
     Ok(resolved_value)
 }
 
@@ -933,25 +898,13 @@ pub fn vtable_trait_upcasting_coercion_new_vptr_slot<'tcx>(
         def_id: unsize_trait_did,
         substs: tcx.mk_substs_trait(source, &[target.into()]),
     };
-    let obligation = Obligation::new(
-        ObligationCause::dummy(),
-        ty::ParamEnv::reveal_all(),
-        ty::Binder::dummy(ty::TraitPredicate {
-            trait_ref,
-            constness: ty::BoundConstness::NotConst,
-            polarity: ty::ImplPolarity::Positive,
-        }),
-    );
 
-    let infcx = tcx.infer_ctxt().build();
-    let mut selcx = SelectionContext::new(&infcx);
-    let implsrc = selcx.select(&obligation).unwrap();
-
-    let Some(ImplSource::TraitUpcasting(implsrc_traitcasting)) = implsrc else {
-        bug!();
-    };
-
-    implsrc_traitcasting.vtable_vptr_slot
+    match tcx.codegen_select_candidate((ty::ParamEnv::reveal_all(), ty::Binder::dummy(trait_ref))) {
+        Ok(ImplSource::TraitUpcasting(implsrc_traitcasting)) => {
+            implsrc_traitcasting.vtable_vptr_slot
+        }
+        otherwise => bug!("expected TraitUpcasting candidate, got {otherwise:?}"),
+    }
 }
 
 pub fn provide(providers: &mut ty::query::Providers) {
diff --git a/compiler/rustc_trait_selection/src/traits/on_unimplemented.rs b/compiler/rustc_trait_selection/src/traits/on_unimplemented.rs
deleted file mode 100644
index 4a4f34b76805..000000000000
--- a/compiler/rustc_trait_selection/src/traits/on_unimplemented.rs
+++ /dev/null
@@ -1,392 +0,0 @@
-use rustc_ast::{MetaItem, NestedMetaItem};
-use rustc_attr as attr;
-use rustc_data_structures::fx::FxHashMap;
-use rustc_errors::{struct_span_err, ErrorGuaranteed};
-use rustc_hir::def_id::DefId;
-use rustc_middle::ty::{self, GenericParamDefKind, TyCtxt};
-use rustc_parse_format::{ParseMode, Parser, Piece, Position};
-use rustc_span::symbol::{kw, sym, Symbol};
-use rustc_span::{Span, DUMMY_SP};
-
-use crate::errors::{
-    EmptyOnClauseInOnUnimplemented, InvalidOnClauseInOnUnimplemented, NoValueInOnUnimplemented,
-};
-
-#[derive(Clone, Debug)]
-pub struct OnUnimplementedFormatString(Symbol);
-
-#[derive(Debug)]
-pub struct OnUnimplementedDirective {
-    pub condition: Option<MetaItem>,
-    pub subcommands: Vec<OnUnimplementedDirective>,
-    pub message: Option<OnUnimplementedFormatString>,
-    pub label: Option<OnUnimplementedFormatString>,
-    pub note: Option<OnUnimplementedFormatString>,
-    pub parent_label: Option<OnUnimplementedFormatString>,
-    pub append_const_msg: Option<Option<Symbol>>,
-}
-
-#[derive(Default)]
-pub struct OnUnimplementedNote {
-    pub message: Option<String>,
-    pub label: Option<String>,
-    pub note: Option<String>,
-    pub parent_label: Option<String>,
-    /// Append a message for `~const Trait` errors. `None` means not requested and
-    /// should fallback to a generic message, `Some(None)` suggests using the default
-    /// appended message, `Some(Some(s))` suggests use the `s` message instead of the
-    /// default one..
-    pub append_const_msg: Option<Option<Symbol>>,
-}
-
-impl<'tcx> OnUnimplementedDirective {
-    fn parse(
-        tcx: TyCtxt<'tcx>,
-        item_def_id: DefId,
-        items: &[NestedMetaItem],
-        span: Span,
-        is_root: bool,
-    ) -> Result<Self, ErrorGuaranteed> {
-        let mut errored = None;
-        let mut item_iter = items.iter();
-
-        let parse_value = |value_str| {
-            OnUnimplementedFormatString::try_parse(tcx, item_def_id, value_str, span).map(Some)
-        };
-
-        let condition = if is_root {
-            None
-        } else {
-            let cond = item_iter
-                .next()
-                .ok_or_else(|| tcx.sess.emit_err(EmptyOnClauseInOnUnimplemented { span }))?
-                .meta_item()
-                .ok_or_else(|| tcx.sess.emit_err(InvalidOnClauseInOnUnimplemented { span }))?;
-            attr::eval_condition(cond, &tcx.sess.parse_sess, Some(tcx.features()), &mut |cfg| {
-                if let Some(value) = cfg.value && let Err(guar) = parse_value(value) {
-                    errored = Some(guar);
-                }
-                true
-            });
-            Some(cond.clone())
-        };
-
-        let mut message = None;
-        let mut label = None;
-        let mut note = None;
-        let mut parent_label = None;
-        let mut subcommands = vec![];
-        let mut append_const_msg = None;
-
-        for item in item_iter {
-            if item.has_name(sym::message) && message.is_none() {
-                if let Some(message_) = item.value_str() {
-                    message = parse_value(message_)?;
-                    continue;
-                }
-            } else if item.has_name(sym::label) && label.is_none() {
-                if let Some(label_) = item.value_str() {
-                    label = parse_value(label_)?;
-                    continue;
-                }
-            } else if item.has_name(sym::note) && note.is_none() {
-                if let Some(note_) = item.value_str() {
-                    note = parse_value(note_)?;
-                    continue;
-                }
-            } else if item.has_name(sym::parent_label) && parent_label.is_none() {
-                if let Some(parent_label_) = item.value_str() {
-                    parent_label = parse_value(parent_label_)?;
-                    continue;
-                }
-            } else if item.has_name(sym::on)
-                && is_root
-                && message.is_none()
-                && label.is_none()
-                && note.is_none()
-            {
-                if let Some(items) = item.meta_item_list() {
-                    match Self::parse(tcx, item_def_id, &items, item.span(), false) {
-                        Ok(subcommand) => subcommands.push(subcommand),
-                        Err(reported) => errored = Some(reported),
-                    };
-                    continue;
-                }
-            } else if item.has_name(sym::append_const_msg) && append_const_msg.is_none() {
-                if let Some(msg) = item.value_str() {
-                    append_const_msg = Some(Some(msg));
-                    continue;
-                } else if item.is_word() {
-                    append_const_msg = Some(None);
-                    continue;
-                }
-            }
-
-            // nothing found
-            tcx.sess.emit_err(NoValueInOnUnimplemented { span: item.span() });
-        }
-
-        if let Some(reported) = errored {
-            Err(reported)
-        } else {
-            Ok(OnUnimplementedDirective {
-                condition,
-                subcommands,
-                message,
-                label,
-                note,
-                parent_label,
-                append_const_msg,
-            })
-        }
-    }
-
-    pub fn of_item(tcx: TyCtxt<'tcx>, item_def_id: DefId) -> Result<Option<Self>, ErrorGuaranteed> {
-        let Some(attr) = tcx.get_attr(item_def_id, sym::rustc_on_unimplemented) else {
-            return Ok(None);
-        };
-
-        let result = if let Some(items) = attr.meta_item_list() {
-            Self::parse(tcx, item_def_id, &items, attr.span, true).map(Some)
-        } else if let Some(value) = attr.value_str() {
-            Ok(Some(OnUnimplementedDirective {
-                condition: None,
-                message: None,
-                subcommands: vec![],
-                label: Some(OnUnimplementedFormatString::try_parse(
-                    tcx,
-                    item_def_id,
-                    value,
-                    attr.span,
-                )?),
-                note: None,
-                parent_label: None,
-                append_const_msg: None,
-            }))
-        } else {
-            let reported =
-                tcx.sess.delay_span_bug(DUMMY_SP, "of_item: neither meta_item_list nor value_str");
-            return Err(reported);
-        };
-        debug!("of_item({:?}) = {:?}", item_def_id, result);
-        result
-    }
-
-    pub fn evaluate(
-        &self,
-        tcx: TyCtxt<'tcx>,
-        trait_ref: ty::TraitRef<'tcx>,
-        options: &[(Symbol, Option<String>)],
-    ) -> OnUnimplementedNote {
-        let mut message = None;
-        let mut label = None;
-        let mut note = None;
-        let mut parent_label = None;
-        let mut append_const_msg = None;
-        info!("evaluate({:?}, trait_ref={:?}, options={:?})", self, trait_ref, options);
-
-        let options_map: FxHashMap<Symbol, String> =
-            options.iter().filter_map(|(k, v)| v.as_ref().map(|v| (*k, v.to_owned()))).collect();
-
-        for command in self.subcommands.iter().chain(Some(self)).rev() {
-            if let Some(ref condition) = command.condition && !attr::eval_condition(
-                condition,
-                &tcx.sess.parse_sess,
-                Some(tcx.features()),
-                &mut |cfg| {
-                    let value = cfg.value.map(|v| {
-                        OnUnimplementedFormatString(v).format(tcx, trait_ref, &options_map)
-                    });
-
-                    options.contains(&(cfg.name, value))
-                },
-            ) {
-                debug!("evaluate: skipping {:?} due to condition", command);
-                continue;
-            }
-            debug!("evaluate: {:?} succeeded", command);
-            if let Some(ref message_) = command.message {
-                message = Some(message_.clone());
-            }
-
-            if let Some(ref label_) = command.label {
-                label = Some(label_.clone());
-            }
-
-            if let Some(ref note_) = command.note {
-                note = Some(note_.clone());
-            }
-
-            if let Some(ref parent_label_) = command.parent_label {
-                parent_label = Some(parent_label_.clone());
-            }
-
-            append_const_msg = command.append_const_msg;
-        }
-
-        OnUnimplementedNote {
-            label: label.map(|l| l.format(tcx, trait_ref, &options_map)),
-            message: message.map(|m| m.format(tcx, trait_ref, &options_map)),
-            note: note.map(|n| n.format(tcx, trait_ref, &options_map)),
-            parent_label: parent_label.map(|e_s| e_s.format(tcx, trait_ref, &options_map)),
-            append_const_msg,
-        }
-    }
-}
-
-impl<'tcx> OnUnimplementedFormatString {
-    fn try_parse(
-        tcx: TyCtxt<'tcx>,
-        item_def_id: DefId,
-        from: Symbol,
-        err_sp: Span,
-    ) -> Result<Self, ErrorGuaranteed> {
-        let result = OnUnimplementedFormatString(from);
-        result.verify(tcx, item_def_id, err_sp)?;
-        Ok(result)
-    }
-
-    fn verify(
-        &self,
-        tcx: TyCtxt<'tcx>,
-        item_def_id: DefId,
-        span: Span,
-    ) -> Result<(), ErrorGuaranteed> {
-        let trait_def_id = if tcx.is_trait(item_def_id) {
-            item_def_id
-        } else {
-            tcx.trait_id_of_impl(item_def_id)
-                .expect("expected `on_unimplemented` to correspond to a trait")
-        };
-        let trait_name = tcx.item_name(trait_def_id);
-        let generics = tcx.generics_of(item_def_id);
-        let s = self.0.as_str();
-        let parser = Parser::new(s, None, None, false, ParseMode::Format);
-        let mut result = Ok(());
-        for token in parser {
-            match token {
-                Piece::String(_) => (), // Normal string, no need to check it
-                Piece::NextArgument(a) => match a.position {
-                    Position::ArgumentNamed(s) => {
-                        match Symbol::intern(s) {
-                            // `{Self}` is allowed
-                            kw::SelfUpper => (),
-                            // `{ThisTraitsName}` is allowed
-                            s if s == trait_name => (),
-                            // `{from_method}` is allowed
-                            sym::from_method => (),
-                            // `{from_desugaring}` is allowed
-                            sym::from_desugaring => (),
-                            // `{ItemContext}` is allowed
-                            sym::ItemContext => (),
-                            // `{integral}` and `{integer}` and `{float}` are allowed
-                            sym::integral | sym::integer_ | sym::float => (),
-                            // So is `{A}` if A is a type parameter
-                            s => match generics.params.iter().find(|param| param.name == s) {
-                                Some(_) => (),
-                                None => {
-                                    let reported = struct_span_err!(
-                                        tcx.sess,
-                                        span,
-                                        E0230,
-                                        "there is no parameter `{}` on {}",
-                                        s,
-                                        if trait_def_id == item_def_id {
-                                            format!("trait `{}`", trait_name)
-                                        } else {
-                                            "impl".to_string()
-                                        }
-                                    )
-                                    .emit();
-                                    result = Err(reported);
-                                }
-                            },
-                        }
-                    }
-                    // `{:1}` and `{}` are not to be used
-                    Position::ArgumentIs(..) | Position::ArgumentImplicitlyIs(_) => {
-                        let reported = struct_span_err!(
-                            tcx.sess,
-                            span,
-                            E0231,
-                            "only named substitution parameters are allowed"
-                        )
-                        .emit();
-                        result = Err(reported);
-                    }
-                },
-            }
-        }
-
-        result
-    }
-
-    pub fn format(
-        &self,
-        tcx: TyCtxt<'tcx>,
-        trait_ref: ty::TraitRef<'tcx>,
-        options: &FxHashMap<Symbol, String>,
-    ) -> String {
-        let name = tcx.item_name(trait_ref.def_id);
-        let trait_str = tcx.def_path_str(trait_ref.def_id);
-        let generics = tcx.generics_of(trait_ref.def_id);
-        let generic_map = generics
-            .params
-            .iter()
-            .filter_map(|param| {
-                let value = match param.kind {
-                    GenericParamDefKind::Type { .. } | GenericParamDefKind::Const { .. } => {
-                        trait_ref.substs[param.index as usize].to_string()
-                    }
-                    GenericParamDefKind::Lifetime => return None,
-                };
-                let name = param.name;
-                Some((name, value))
-            })
-            .collect::<FxHashMap<Symbol, String>>();
-        let empty_string = String::new();
-
-        let s = self.0.as_str();
-        let parser = Parser::new(s, None, None, false, ParseMode::Format);
-        let item_context = (options.get(&sym::ItemContext)).unwrap_or(&empty_string);
-        parser
-            .map(|p| match p {
-                Piece::String(s) => s,
-                Piece::NextArgument(a) => match a.position {
-                    Position::ArgumentNamed(s) => {
-                        let s = Symbol::intern(s);
-                        match generic_map.get(&s) {
-                            Some(val) => val,
-                            None if s == name => &trait_str,
-                            None => {
-                                if let Some(val) = options.get(&s) {
-                                    val
-                                } else if s == sym::from_desugaring || s == sym::from_method {
-                                    // don't break messages using these two arguments incorrectly
-                                    &empty_string
-                                } else if s == sym::ItemContext {
-                                    &item_context
-                                } else if s == sym::integral {
-                                    "{integral}"
-                                } else if s == sym::integer_ {
-                                    "{integer}"
-                                } else if s == sym::float {
-                                    "{float}"
-                                } else {
-                                    bug!(
-                                        "broken on_unimplemented {:?} for {:?}: \
-                                      no argument matching {:?}",
-                                        self.0,
-                                        trait_ref,
-                                        s
-                                    )
-                                }
-                            }
-                        }
-                    }
-                    _ => bug!("broken on_unimplemented {:?} - bad format arg", self.0),
-                },
-            })
-            .collect()
-    }
-}
diff --git a/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs b/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs
index 108dae092cfe..e1092a788e32 100644
--- a/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs
+++ b/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs
@@ -1,8 +1,8 @@
 use crate::infer::InferCtxt;
 use crate::traits::query::type_op::{self, TypeOp, TypeOpOutput};
 use crate::traits::query::NoSolution;
-use crate::traits::{ObligationCause, TraitEngine, TraitEngineExt};
-use rustc_data_structures::fx::FxHashSet;
+use crate::traits::ObligationCause;
+use rustc_data_structures::fx::FxIndexSet;
 use rustc_hir as hir;
 use rustc_hir::HirId;
 use rustc_middle::ty::{self, ParamEnv, Ty};
@@ -22,7 +22,7 @@ pub trait InferCtxtExt<'a, 'tcx> {
         &'a self,
         param_env: ty::ParamEnv<'tcx>,
         body_id: hir::HirId,
-        tys: FxHashSet<Ty<'tcx>>,
+        tys: FxIndexSet<Ty<'tcx>>,
     ) -> Bounds<'a, 'tcx>;
 }
 
@@ -74,20 +74,20 @@ impl<'a, 'tcx: 'a> InferCtxtExt<'a, 'tcx> for InferCtxt<'tcx> {
             debug!(?constraints);
             // Instantiation may have produced new inference variables and constraints on those
             // variables. Process these constraints.
-            let mut fulfill_cx = <dyn TraitEngine<'tcx>>::new(self.tcx);
             let cause = ObligationCause::misc(span, body_id);
-            for &constraint in &constraints.outlives {
-                let obligation = self.query_outlives_constraint_to_obligation(
-                    constraint,
-                    cause.clone(),
-                    param_env,
-                );
-                fulfill_cx.register_predicate_obligation(self, obligation);
-            }
+            let errors = super::fully_solve_obligations(
+                self,
+                constraints.outlives.iter().map(|constraint| {
+                    self.query_outlives_constraint_to_obligation(
+                        *constraint,
+                        cause.clone(),
+                        param_env,
+                    )
+                }),
+            );
             if !constraints.member_constraints.is_empty() {
                 span_bug!(span, "{:#?}", constraints.member_constraints);
             }
-            let errors = fulfill_cx.select_all_or_error(self);
             if !errors.is_empty() {
                 self.tcx.sess.delay_span_bug(
                     span,
@@ -103,7 +103,7 @@ impl<'a, 'tcx: 'a> InferCtxtExt<'a, 'tcx> for InferCtxt<'tcx> {
         &'a self,
         param_env: ParamEnv<'tcx>,
         body_id: HirId,
-        tys: FxHashSet<Ty<'tcx>>,
+        tys: FxIndexSet<Ty<'tcx>>,
     ) -> Bounds<'a, 'tcx> {
         tys.into_iter()
             .map(move |ty| {
diff --git a/compiler/rustc_trait_selection/src/traits/project.rs b/compiler/rustc_trait_selection/src/traits/project.rs
index c8276854016f..572f82117cc0 100644
--- a/compiler/rustc_trait_selection/src/traits/project.rs
+++ b/compiler/rustc_trait_selection/src/traits/project.rs
@@ -647,7 +647,7 @@ impl<'a, 'b, 'tcx> TypeFolder<'tcx> for AssocTypeNormalizer<'a, 'b, 'tcx> {
     #[instrument(skip(self), level = "debug")]
     fn fold_const(&mut self, constant: ty::Const<'tcx>) -> ty::Const<'tcx> {
         let tcx = self.selcx.tcx();
-        if tcx.lazy_normalization() {
+        if tcx.lazy_normalization() || !needs_normalization(&constant, self.param_env.reveal()) {
             constant
         } else {
             let constant = constant.super_fold_with(self);
@@ -831,9 +831,7 @@ impl<'tcx> TypeFolder<'tcx> for BoundVarReplacer<'_, 'tcx> {
                 let universe = self.universe_for(debruijn);
                 let p = ty::PlaceholderConst { universe, name: bound_const };
                 self.mapped_consts.insert(p, bound_const);
-                self.infcx
-                    .tcx
-                    .mk_const(ty::ConstS { kind: ty::ConstKind::Placeholder(p), ty: ct.ty() })
+                self.infcx.tcx.mk_const(ty::ConstKind::Placeholder(p), ct.ty())
             }
             _ => ct.super_fold_with(self),
         }
@@ -968,10 +966,7 @@ impl<'tcx> TypeFolder<'tcx> for PlaceholderReplacer<'_, 'tcx> {
                     let db = ty::DebruijnIndex::from_usize(
                         self.universe_indices.len() - index + self.current_index.as_usize() - 1,
                     );
-                    self.tcx().mk_const(ty::ConstS {
-                        kind: ty::ConstKind::Bound(db, *replace_var),
-                        ty: ct.ty(),
-                    })
+                    self.tcx().mk_const(ty::ConstKind::Bound(db, *replace_var), ct.ty())
                 }
                 None => ct,
             }
@@ -2173,7 +2168,7 @@ fn confirm_impl_candidate<'cx, 'tcx>(
             crate::traits::InternalSubsts::identity_for_item(tcx, assoc_ty.item.def_id);
         let did = ty::WithOptConstParam::unknown(assoc_ty.item.def_id);
         let kind = ty::ConstKind::Unevaluated(ty::UnevaluatedConst::new(did, identity_substs));
-        ty.map_bound(|ty| tcx.mk_const(ty::ConstS { ty, kind }).into())
+        ty.map_bound(|ty| tcx.mk_const(kind, ty).into())
     } else {
         ty.map_bound(|ty| ty.into())
     };
@@ -2192,7 +2187,7 @@ fn confirm_impl_candidate<'cx, 'tcx>(
 // Verify that the trait item and its implementation have compatible substs lists
 fn check_substs_compatible<'tcx>(
     tcx: TyCtxt<'tcx>,
-    assoc_ty: &ty::AssocItem,
+    assoc_item: &ty::AssocItem,
     substs: ty::SubstsRef<'tcx>,
 ) -> bool {
     fn check_substs_compatible_inner<'tcx>(
@@ -2224,7 +2219,10 @@ fn check_substs_compatible<'tcx>(
         true
     }
 
-    check_substs_compatible_inner(tcx, tcx.generics_of(assoc_ty.def_id), substs.as_slice())
+    let generics = tcx.generics_of(assoc_item.def_id);
+    // Chop off any additional substs (RPITIT) substs
+    let substs = &substs[0..generics.count().min(substs.len())];
+    check_substs_compatible_inner(tcx, generics, substs)
 }
 
 fn confirm_impl_trait_in_trait_candidate<'tcx>(
@@ -2253,11 +2251,27 @@ fn confirm_impl_trait_in_trait_candidate<'tcx>(
         };
     }
 
-    let impl_fn_def_id = leaf_def.item.def_id;
     // Rebase from {trait}::{fn}::{opaque} to {impl}::{fn}::{opaque},
     // since `data.substs` are the impl substs.
     let impl_fn_substs =
         obligation.predicate.substs.rebase_onto(tcx, tcx.parent(trait_fn_def_id), data.substs);
+    let impl_fn_substs = translate_substs(
+        selcx.infcx(),
+        obligation.param_env,
+        data.impl_def_id,
+        impl_fn_substs,
+        leaf_def.defining_node,
+    );
+
+    if !check_substs_compatible(tcx, &leaf_def.item, impl_fn_substs) {
+        let err = tcx.ty_error_with_message(
+            obligation.cause.span,
+            "impl method and trait method have different parameters",
+        );
+        return Progress { term: err.into(), obligations };
+    }
+
+    let impl_fn_def_id = leaf_def.item.def_id;
 
     let cause = ObligationCause::new(
         obligation.cause.span,
diff --git a/compiler/rustc_trait_selection/src/traits/query/normalize.rs b/compiler/rustc_trait_selection/src/traits/query/normalize.rs
index 715f5be8e2f4..a7932b332c94 100644
--- a/compiler/rustc_trait_selection/src/traits/query/normalize.rs
+++ b/compiler/rustc_trait_selection/src/traits/query/normalize.rs
@@ -353,6 +353,10 @@ impl<'cx, 'tcx> FallibleTypeFolder<'tcx> for QueryNormalizer<'cx, 'tcx> {
         &mut self,
         constant: ty::Const<'tcx>,
     ) -> Result<ty::Const<'tcx>, Self::Error> {
+        if !needs_normalization(&constant, self.param_env.reveal()) {
+            return Ok(constant);
+        }
+
         let constant = constant.try_super_fold_with(self)?;
         debug!(?constant, ?self.param_env);
         Ok(crate::traits::project::with_replaced_escaping_bound_vars(
diff --git a/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs b/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs
index 4c5bc333961d..3671a0d87df5 100644
--- a/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs
+++ b/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs
@@ -20,7 +20,7 @@ use crate::traits;
 use crate::traits::coherence::Conflict;
 use crate::traits::query::evaluate_obligation::InferCtxtExt;
 use crate::traits::{util, SelectionResult};
-use crate::traits::{Ambiguous, ErrorReporting, Overflow, Unimplemented};
+use crate::traits::{ErrorReporting, Overflow, Unimplemented};
 
 use super::BuiltinImplConditions;
 use super::IntercrateAmbiguityCause;
@@ -200,15 +200,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                     // and report ambiguity.
                     if i > 1 {
                         debug!("multiple matches, ambig");
-                        return Err(Ambiguous(
-                            candidates
-                                .into_iter()
-                                .filter_map(|c| match c.candidate {
-                                    SelectionCandidate::ImplCandidate(def_id) => Some(def_id),
-                                    _ => None,
-                                })
-                                .collect(),
-                        ));
+                        return Ok(None);
                     }
                 }
             }
diff --git a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
index ed22058c6461..28b4bae7cbec 100644
--- a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
+++ b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
@@ -555,13 +555,13 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                             GenericParamDefKind::Const { .. } => {
                                 let bound_var = ty::BoundVariableKind::Const;
                                 bound_vars.push(bound_var);
-                                tcx.mk_const(ty::ConstS {
-                                    ty: tcx.type_of(param.def_id),
-                                    kind: ty::ConstKind::Bound(
+                                tcx.mk_const(
+                                    ty::ConstKind::Bound(
                                         ty::INNERMOST,
                                         ty::BoundVar::from_usize(bound_vars.len() - 1),
                                     ),
-                                })
+                                    tcx.type_of(param.def_id),
+                                )
                                 .into()
                             }
                         });
diff --git a/compiler/rustc_trait_selection/src/traits/select/mod.rs b/compiler/rustc_trait_selection/src/traits/select/mod.rs
index 9ebff4892016..a12f67125bbc 100644
--- a/compiler/rustc_trait_selection/src/traits/select/mod.rs
+++ b/compiler/rustc_trait_selection/src/traits/select/mod.rs
@@ -2,6 +2,12 @@
 //!
 //! [rustc dev guide]: https://rustc-dev-guide.rust-lang.org/traits/resolution.html#selection
 
+// FIXME: The `map` field in ProvisionalEvaluationCache should be changed to
+// a `FxIndexMap` to avoid query instability, but right now it causes a perf regression. This would be
+// fixed or at least lightened by the addition of the `drain_filter` method to `FxIndexMap`
+// Relevant: https://github.com/rust-lang/rust/pull/103723 and https://github.com/bluss/indexmap/issues/242
+#![allow(rustc::potential_query_instability)]
+
 use self::EvaluationResult::*;
 use self::SelectionCandidate::*;
 
@@ -24,7 +30,8 @@ use crate::traits::error_reporting::TypeErrCtxtExt;
 use crate::traits::project::ProjectAndUnifyResult;
 use crate::traits::project::ProjectionCacheKeyExt;
 use crate::traits::ProjectionCacheKey;
-use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexSet};
+use rustc_data_structures::fx::FxHashMap;
+use rustc_data_structures::fx::{FxHashSet, FxIndexSet};
 use rustc_data_structures::stack::ensure_sufficient_stack;
 use rustc_errors::{Diagnostic, ErrorGuaranteed};
 use rustc_hir as hir;
@@ -294,9 +301,6 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                 assert!(self.query_mode == TraitQueryMode::Canonical);
                 return Err(SelectionError::Overflow(OverflowError::Canonical));
             }
-            Err(SelectionError::Ambiguous(_)) => {
-                return Ok(None);
-            }
             Err(e) => {
                 return Err(e);
             }
@@ -931,7 +935,6 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
 
         match self.candidate_from_obligation(stack) {
             Ok(Some(c)) => self.evaluate_candidate(stack, &c),
-            Err(SelectionError::Ambiguous(_)) => Ok(EvaluatedToAmbig),
             Ok(None) => Ok(EvaluatedToAmbig),
             Err(Overflow(OverflowError::Canonical)) => Err(OverflowError::Canonical),
             Err(ErrorReporting) => Err(OverflowError::ErrorReporting),
@@ -956,7 +959,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
 
     fn coinductive_predicate(&self, predicate: ty::Predicate<'tcx>) -> bool {
         let result = match predicate.kind().skip_binder() {
-            ty::PredicateKind::Trait(ref data) => self.tcx().trait_is_auto(data.def_id()),
+            ty::PredicateKind::Trait(ref data) => self.tcx().trait_is_coinductive(data.def_id()),
             ty::PredicateKind::WellFormed(_) => true,
             _ => false,
         };
@@ -1132,12 +1135,13 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
 
     /// filter_impls filters constant trait obligations and candidates that have a positive impl
     /// for a negative goal and a negative impl for a positive goal
-    #[instrument(level = "debug", skip(self))]
+    #[instrument(level = "debug", skip(self, candidates))]
     fn filter_impls(
         &mut self,
         candidates: Vec<SelectionCandidate<'tcx>>,
         obligation: &TraitObligation<'tcx>,
     ) -> Vec<SelectionCandidate<'tcx>> {
+        trace!("{candidates:#?}");
         let tcx = self.tcx();
         let mut result = Vec::with_capacity(candidates.len());
 
@@ -1177,6 +1181,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
             }
         }
 
+        trace!("{result:#?}");
         result
     }
 
@@ -1973,6 +1978,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
     /// Bar<i32> where struct Bar<T> { x: T, y: u32 } -> [i32, u32]
     /// Zed<i32> where enum Zed { A(T), B(u32) } -> [i32, u32]
     /// ```
+    #[instrument(level = "debug", skip(self), ret)]
     fn constituent_types_for_ty(
         &self,
         t: ty::Binder<'tcx, Ty<'tcx>>,
diff --git a/compiler/rustc_trait_selection/src/traits/specialize/mod.rs b/compiler/rustc_trait_selection/src/traits/specialize/mod.rs
index c891658582a0..7cc12eff20e8 100644
--- a/compiler/rustc_trait_selection/src/traits/specialize/mod.rs
+++ b/compiler/rustc_trait_selection/src/traits/specialize/mod.rs
@@ -10,16 +10,18 @@
 //! [rustc dev guide]: https://rustc-dev-guide.rust-lang.org/traits/specialization.html
 
 pub mod specialization_graph;
+use rustc_infer::traits::{TraitEngine, TraitEngineExt as _};
 use specialization_graph::GraphExt;
 
 use crate::errors::NegativePositiveConflict;
 use crate::infer::{InferCtxt, InferOk, TyCtxtInferExt};
+use crate::traits::engine::TraitEngineExt as _;
 use crate::traits::select::IntercrateAmbiguityCause;
 use crate::traits::{self, coherence, FutureCompatOverlapErrorKind, ObligationCause};
-use rustc_data_structures::fx::{FxHashSet, FxIndexSet};
-use rustc_errors::{struct_span_err, DiagnosticBuilder, EmissionGuarantee};
+use rustc_data_structures::fx::FxIndexSet;
+use rustc_errors::{error_code, DelayDm, Diagnostic};
 use rustc_hir::def_id::{DefId, LocalDefId};
-use rustc_middle::ty::{self, ImplSubject, TyCtxt};
+use rustc_middle::ty::{self, ImplSubject, Ty, TyCtxt};
 use rustc_middle::ty::{InternalSubsts, SubstsRef};
 use rustc_session::lint::builtin::COHERENCE_LEAK_CHECK;
 use rustc_session::lint::builtin::ORDER_DEPENDENT_TRAIT_OBJECTS;
@@ -30,10 +32,10 @@ use super::SelectionContext;
 
 /// Information pertinent to an overlapping impl error.
 #[derive(Debug)]
-pub struct OverlapError {
+pub struct OverlapError<'tcx> {
     pub with_impl: DefId,
-    pub trait_desc: String,
-    pub self_desc: Option<String>,
+    pub trait_ref: ty::TraitRef<'tcx>,
+    pub self_ty: Option<Ty<'tcx>>,
     pub intercrate_ambiguity_causes: FxIndexSet<IntercrateAmbiguityCause>,
     pub involves_placeholder: bool,
 }
@@ -200,36 +202,32 @@ fn fulfill_implication<'tcx>(
         return Err(());
     };
 
+    // Needs to be `in_snapshot` because this function is used to rebase
+    // substitutions, which may happen inside of a select within a probe.
+    let mut engine = <dyn TraitEngine<'tcx>>::new_in_snapshot(infcx.tcx);
     // attempt to prove all of the predicates for impl2 given those for impl1
     // (which are packed up in penv)
+    engine.register_predicate_obligations(infcx, obligations.chain(more_obligations));
 
-    infcx.save_and_restore_in_snapshot_flag(|infcx| {
-        let errors = traits::fully_solve_obligations(&infcx, obligations.chain(more_obligations));
-        match &errors[..] {
-            [] => {
-                debug!(
-                    "fulfill_implication: an impl for {:?} specializes {:?}",
-                    source_trait, target_trait
-                );
+    let errors = engine.select_all_or_error(infcx);
+    if !errors.is_empty() {
+        // no dice!
+        debug!(
+            "fulfill_implication: for impls on {:?} and {:?}, \
+                 could not fulfill: {:?} given {:?}",
+            source_trait,
+            target_trait,
+            errors,
+            param_env.caller_bounds()
+        );
+        return Err(());
+    }
 
-                // Now resolve the *substitution* we built for the target earlier, replacing
-                // the inference variables inside with whatever we got from fulfillment.
-                Ok(infcx.resolve_vars_if_possible(target_substs))
-            }
-            errors => {
-                // no dice!
-                debug!(
-                    "fulfill_implication: for impls on {:?} and {:?}, \
-                     could not fulfill: {:?} given {:?}",
-                    source_trait,
-                    target_trait,
-                    errors,
-                    param_env.caller_bounds()
-                );
-                Err(())
-            }
-        }
-    })
+    debug!("fulfill_implication: an impl for {:?} specializes {:?}", source_trait, target_trait);
+
+    // Now resolve the *substitution* we built for the target earlier, replacing
+    // the inference variables inside with whatever we got from fulfillment.
+    Ok(infcx.resolve_vars_if_possible(target_substs))
 }
 
 // Query provider for `specialization_graph_of`.
@@ -277,9 +275,9 @@ pub(super) fn specialization_graph_provider(
 // it negatively impacts perf.
 #[cold]
 #[inline(never)]
-fn report_overlap_conflict(
-    tcx: TyCtxt<'_>,
-    overlap: OverlapError,
+fn report_overlap_conflict<'tcx>(
+    tcx: TyCtxt<'tcx>,
+    overlap: OverlapError<'tcx>,
     impl_def_id: LocalDefId,
     used_to_be_allowed: Option<FutureCompatOverlapErrorKind>,
     sg: &mut specialization_graph::Graph,
@@ -315,9 +313,9 @@ fn report_overlap_conflict(
     }
 }
 
-fn report_negative_positive_conflict(
-    tcx: TyCtxt<'_>,
-    overlap: &OverlapError,
+fn report_negative_positive_conflict<'tcx>(
+    tcx: TyCtxt<'tcx>,
+    overlap: &OverlapError<'tcx>,
     local_impl_def_id: LocalDefId,
     negative_impl_def_id: DefId,
     positive_impl_def_id: DefId,
@@ -325,17 +323,17 @@ fn report_negative_positive_conflict(
 ) {
     let mut err = tcx.sess.create_err(NegativePositiveConflict {
         impl_span: tcx.def_span(local_impl_def_id),
-        trait_desc: &overlap.trait_desc,
-        self_desc: &overlap.self_desc,
+        trait_desc: overlap.trait_ref,
+        self_ty: overlap.self_ty,
         negative_impl_span: tcx.span_of_impl(negative_impl_def_id),
         positive_impl_span: tcx.span_of_impl(positive_impl_def_id),
     });
     sg.has_errored = Some(err.emit());
 }
 
-fn report_conflicting_impls(
-    tcx: TyCtxt<'_>,
-    overlap: OverlapError,
+fn report_conflicting_impls<'tcx>(
+    tcx: TyCtxt<'tcx>,
+    overlap: OverlapError<'tcx>,
     impl_def_id: LocalDefId,
     used_to_be_allowed: Option<FutureCompatOverlapErrorKind>,
     sg: &mut specialization_graph::Graph,
@@ -345,12 +343,12 @@ fn report_conflicting_impls(
     // Work to be done after we've built the DiagnosticBuilder. We have to define it
     // now because the struct_lint methods don't return back the DiagnosticBuilder
     // that's passed in.
-    fn decorate<'a, 'b, G: EmissionGuarantee>(
-        tcx: TyCtxt<'_>,
-        overlap: OverlapError,
+    fn decorate<'tcx>(
+        tcx: TyCtxt<'tcx>,
+        overlap: &OverlapError<'tcx>,
         impl_span: Span,
-        err: &'b mut DiagnosticBuilder<'a, G>,
-    ) -> &'b mut DiagnosticBuilder<'a, G> {
+        err: &mut Diagnostic,
+    ) {
         match tcx.span_of_impl(overlap.with_impl) {
             Ok(span) => {
                 err.span_label(span, "first implementation here");
@@ -359,7 +357,7 @@ fn report_conflicting_impls(
                     impl_span,
                     format!(
                         "conflicting implementation{}",
-                        overlap.self_desc.map_or_else(String::new, |ty| format!(" for `{}`", ty))
+                        overlap.self_ty.map_or_else(String::new, |ty| format!(" for `{}`", ty))
                     ),
                 );
             }
@@ -381,26 +379,28 @@ fn report_conflicting_impls(
         if overlap.involves_placeholder {
             coherence::add_placeholder_note(err);
         }
-        err
     }
 
-    let msg = format!(
-        "conflicting implementations of trait `{}`{}{}",
-        overlap.trait_desc,
-        overlap.self_desc.as_deref().map_or_else(String::new, |ty| format!(" for type `{ty}`")),
-        match used_to_be_allowed {
-            Some(FutureCompatOverlapErrorKind::Issue33140) => ": (E0119)",
-            _ => "",
-        }
-    );
+    let msg = DelayDm(|| {
+        format!(
+            "conflicting implementations of trait `{}`{}{}",
+            overlap.trait_ref.print_only_trait_path(),
+            overlap.self_ty.map_or_else(String::new, |ty| format!(" for type `{ty}`")),
+            match used_to_be_allowed {
+                Some(FutureCompatOverlapErrorKind::Issue33140) => ": (E0119)",
+                _ => "",
+            }
+        )
+    });
 
     match used_to_be_allowed {
         None => {
             let reported = if overlap.with_impl.is_local()
                 || tcx.orphan_check_impl(impl_def_id).is_ok()
             {
-                let mut err = struct_span_err!(tcx.sess, impl_span, E0119, "{msg}",);
-                decorate(tcx, overlap, impl_span, &mut err);
+                let mut err = tcx.sess.struct_span_err(impl_span, msg);
+                err.code(error_code!(E0119));
+                decorate(tcx, &overlap, impl_span, &mut err);
                 Some(err.emit())
             } else {
                 Some(tcx.sess.delay_span_bug(impl_span, "impl should have failed the orphan check"))
@@ -417,7 +417,10 @@ fn report_conflicting_impls(
                 tcx.hir().local_def_id_to_hir_id(impl_def_id),
                 impl_span,
                 msg,
-                |err| decorate(tcx, overlap, impl_span, err),
+                |err| {
+                    decorate(tcx, &overlap, impl_span, err);
+                    err
+                },
             );
         }
     };
@@ -435,7 +438,7 @@ pub(crate) fn to_pretty_impl_header(tcx: TyCtxt<'_>, impl_def_id: DefId) -> Opti
 
     // FIXME: Currently only handles ?Sized.
     //        Needs to support ?Move and ?DynSized when they are implemented.
-    let mut types_without_default_bounds = FxHashSet::default();
+    let mut types_without_default_bounds = FxIndexSet::default();
     let sized_trait = tcx.lang_items().sized_trait();
 
     if !substs.is_empty() {
diff --git a/compiler/rustc_trait_selection/src/traits/specialize/specialization_graph.rs b/compiler/rustc_trait_selection/src/traits/specialize/specialization_graph.rs
index 63f89a33e8ad..4546c9533930 100644
--- a/compiler/rustc_trait_selection/src/traits/specialize/specialization_graph.rs
+++ b/compiler/rustc_trait_selection/src/traits/specialize/specialization_graph.rs
@@ -3,7 +3,6 @@ use super::OverlapError;
 use crate::traits;
 use rustc_hir::def_id::DefId;
 use rustc_middle::ty::fast_reject::{self, SimplifiedType, TreatParams};
-use rustc_middle::ty::print::with_no_trimmed_paths;
 use rustc_middle::ty::{self, TyCtxt, TypeVisitable};
 
 pub use rustc_middle::traits::specialization_graph::*;
@@ -15,15 +14,15 @@ pub enum FutureCompatOverlapErrorKind {
 }
 
 #[derive(Debug)]
-pub struct FutureCompatOverlapError {
-    pub error: OverlapError,
+pub struct FutureCompatOverlapError<'tcx> {
+    pub error: OverlapError<'tcx>,
     pub kind: FutureCompatOverlapErrorKind,
 }
 
 /// The result of attempting to insert an impl into a group of children.
-enum Inserted {
+enum Inserted<'tcx> {
     /// The impl was inserted as a new child in this group of children.
-    BecameNewSibling(Option<FutureCompatOverlapError>),
+    BecameNewSibling(Option<FutureCompatOverlapError<'tcx>>),
 
     /// The impl should replace existing impls [X1, ..], because the impl specializes X1, X2, etc.
     ReplaceChildren(Vec<DefId>),
@@ -42,12 +41,12 @@ trait ChildrenExt<'tcx> {
         impl_def_id: DefId,
         simplified_self: Option<SimplifiedType>,
         overlap_mode: OverlapMode,
-    ) -> Result<Inserted, OverlapError>;
+    ) -> Result<Inserted<'tcx>, OverlapError<'tcx>>;
 }
 
-impl ChildrenExt<'_> for Children {
+impl<'tcx> ChildrenExt<'tcx> for Children {
     /// Insert an impl into this set of children without comparing to any existing impls.
-    fn insert_blindly(&mut self, tcx: TyCtxt<'_>, impl_def_id: DefId) {
+    fn insert_blindly(&mut self, tcx: TyCtxt<'tcx>, impl_def_id: DefId) {
         let trait_ref = tcx.impl_trait_ref(impl_def_id).unwrap();
         if let Some(st) = fast_reject::simplify_type(tcx, trait_ref.self_ty(), TreatParams::AsInfer)
         {
@@ -62,7 +61,7 @@ impl ChildrenExt<'_> for Children {
     /// Removes an impl from this set of children. Used when replacing
     /// an impl with a parent. The impl must be present in the list of
     /// children already.
-    fn remove_existing(&mut self, tcx: TyCtxt<'_>, impl_def_id: DefId) {
+    fn remove_existing(&mut self, tcx: TyCtxt<'tcx>, impl_def_id: DefId) {
         let trait_ref = tcx.impl_trait_ref(impl_def_id).unwrap();
         let vec: &mut Vec<DefId>;
         if let Some(st) = fast_reject::simplify_type(tcx, trait_ref.self_ty(), TreatParams::AsInfer)
@@ -82,11 +81,11 @@ impl ChildrenExt<'_> for Children {
     /// specialization relationships.
     fn insert(
         &mut self,
-        tcx: TyCtxt<'_>,
+        tcx: TyCtxt<'tcx>,
         impl_def_id: DefId,
         simplified_self: Option<SimplifiedType>,
         overlap_mode: OverlapMode,
-    ) -> Result<Inserted, OverlapError> {
+    ) -> Result<Inserted<'tcx>, OverlapError<'tcx>> {
         let mut last_lint = None;
         let mut replace_children = Vec::new();
 
@@ -103,30 +102,23 @@ impl ChildrenExt<'_> for Children {
                 impl_def_id, simplified_self, possible_sibling,
             );
 
-            let create_overlap_error = |overlap: traits::coherence::OverlapResult<'_>| {
+            let create_overlap_error = |overlap: traits::coherence::OverlapResult<'tcx>| {
                 let trait_ref = overlap.impl_header.trait_ref.unwrap();
                 let self_ty = trait_ref.self_ty();
 
-                // FIXME: should postpone string formatting until we decide to actually emit.
-                with_no_trimmed_paths!({
-                    OverlapError {
-                        with_impl: possible_sibling,
-                        trait_desc: trait_ref.print_only_trait_path().to_string(),
-                        // Only report the `Self` type if it has at least
-                        // some outer concrete shell; otherwise, it's
-                        // not adding much information.
-                        self_desc: if self_ty.has_concrete_skeleton() {
-                            Some(self_ty.to_string())
-                        } else {
-                            None
-                        },
-                        intercrate_ambiguity_causes: overlap.intercrate_ambiguity_causes,
-                        involves_placeholder: overlap.involves_placeholder,
-                    }
-                })
+                OverlapError {
+                    with_impl: possible_sibling,
+                    trait_ref,
+                    // Only report the `Self` type if it has at least
+                    // some outer concrete shell; otherwise, it's
+                    // not adding much information.
+                    self_ty: if self_ty.has_concrete_skeleton() { Some(self_ty) } else { None },
+                    intercrate_ambiguity_causes: overlap.intercrate_ambiguity_causes,
+                    involves_placeholder: overlap.involves_placeholder,
+                }
             };
 
-            let report_overlap_error = |overlap: traits::coherence::OverlapResult<'_>,
+            let report_overlap_error = |overlap: traits::coherence::OverlapResult<'tcx>,
                                         last_lint: &mut _| {
                 // Found overlap, but no specialization; error out or report future-compat warning.
 
@@ -255,31 +247,31 @@ where
     }
 }
 
-pub trait GraphExt {
+pub trait GraphExt<'tcx> {
     /// Insert a local impl into the specialization graph. If an existing impl
     /// conflicts with it (has overlap, but neither specializes the other),
     /// information about the area of overlap is returned in the `Err`.
     fn insert(
         &mut self,
-        tcx: TyCtxt<'_>,
+        tcx: TyCtxt<'tcx>,
         impl_def_id: DefId,
         overlap_mode: OverlapMode,
-    ) -> Result<Option<FutureCompatOverlapError>, OverlapError>;
+    ) -> Result<Option<FutureCompatOverlapError<'tcx>>, OverlapError<'tcx>>;
 
     /// Insert cached metadata mapping from a child impl back to its parent.
-    fn record_impl_from_cstore(&mut self, tcx: TyCtxt<'_>, parent: DefId, child: DefId);
+    fn record_impl_from_cstore(&mut self, tcx: TyCtxt<'tcx>, parent: DefId, child: DefId);
 }
 
-impl GraphExt for Graph {
+impl<'tcx> GraphExt<'tcx> for Graph {
     /// Insert a local impl into the specialization graph. If an existing impl
     /// conflicts with it (has overlap, but neither specializes the other),
     /// information about the area of overlap is returned in the `Err`.
     fn insert(
         &mut self,
-        tcx: TyCtxt<'_>,
+        tcx: TyCtxt<'tcx>,
         impl_def_id: DefId,
         overlap_mode: OverlapMode,
-    ) -> Result<Option<FutureCompatOverlapError>, OverlapError> {
+    ) -> Result<Option<FutureCompatOverlapError<'tcx>>, OverlapError<'tcx>> {
         assert!(impl_def_id.is_local());
 
         let trait_ref = tcx.impl_trait_ref(impl_def_id).unwrap();
@@ -376,7 +368,7 @@ impl GraphExt for Graph {
     }
 
     /// Insert cached metadata mapping from a child impl back to its parent.
-    fn record_impl_from_cstore(&mut self, tcx: TyCtxt<'_>, parent: DefId, child: DefId) {
+    fn record_impl_from_cstore(&mut self, tcx: TyCtxt<'tcx>, parent: DefId, child: DefId) {
         if self.parent.insert(child, parent).is_some() {
             bug!(
                 "When recording an impl from the crate store, information about its parent \
diff --git a/compiler/rustc_trait_selection/src/traits/wf.rs b/compiler/rustc_trait_selection/src/traits/wf.rs
index 0870833cc35a..fc0a9f690033 100644
--- a/compiler/rustc_trait_selection/src/traits/wf.rs
+++ b/compiler/rustc_trait_selection/src/traits/wf.rs
@@ -214,7 +214,9 @@ fn extend_cause_with_original_assoc_item_obligation<'tcx>(
         trait_ref, item, cause, pred
     );
     let (items, impl_def_id) = match item {
-        Some(hir::Item { kind: hir::ItemKind::Impl(impl_), def_id, .. }) => (impl_.items, *def_id),
+        Some(hir::Item { kind: hir::ItemKind::Impl(impl_), owner_id, .. }) => {
+            (impl_.items, *owner_id)
+        }
         _ => return,
     };
     let fix_span =
@@ -236,7 +238,7 @@ fn extend_cause_with_original_assoc_item_obligation<'tcx>(
                     tcx.impl_item_implementor_ids(impl_def_id).get(&projection_ty.item_def_id)
                 && let Some(impl_item_span) = items
                     .iter()
-                    .find(|item| item.id.def_id.to_def_id() == impl_item_id)
+                    .find(|item| item.id.owner_id.to_def_id() == impl_item_id)
                     .map(fix_span)
             {
                 cause.span = impl_item_span;
@@ -251,7 +253,7 @@ fn extend_cause_with_original_assoc_item_obligation<'tcx>(
                     tcx.impl_item_implementor_ids(impl_def_id).get(&item_def_id)
                 && let Some(impl_item_span) = items
                     .iter()
-                    .find(|item| item.id.def_id.to_def_id() == impl_item_id)
+                    .find(|item| item.id.owner_id.to_def_id() == impl_item_id)
                     .map(fix_span)
             {
                 cause.span = impl_item_span;
@@ -303,32 +305,6 @@ impl<'tcx> WfPredicates<'tcx> {
         let obligations = if trait_pred.constness == ty::BoundConstness::NotConst {
             self.nominal_obligations_without_const(trait_ref.def_id, trait_ref.substs)
         } else {
-            if !tcx.has_attr(trait_ref.def_id, rustc_span::sym::const_trait) {
-                if let Some(item) = self.item &&
-                   let hir::ItemKind::Impl(impl_) = item.kind &&
-                   let Some(trait_) = &impl_.of_trait &&
-                   let Some(def_id) = trait_.trait_def_id() &&
-                   def_id == trait_ref.def_id
-                {
-                    let trait_name = tcx.item_name(def_id);
-                    let mut err = tcx.sess.struct_span_err(
-                        self.span,
-                        &format!("const `impl` for trait `{trait_name}` which is not marked with `#[const_trait]`"),
-                    );
-                    if def_id.is_local() {
-                        let sp = tcx.def_span(def_id).shrink_to_lo();
-                        err.span_suggestion(sp, &format!("mark `{trait_name}` as const"), "#[const_trait]", rustc_errors::Applicability::MachineApplicable);
-                    }
-                    err.note("marking a trait with `#[const_trait]` ensures all default method bodies are `const`");
-                    err.note("adding a non-const method body in the future would be a breaking change");
-                    err.emit();
-                } else {
-                    tcx.sess.span_err(
-                        self.span,
-                        "~const can only be applied to `#[const_trait]` traits",
-                    );
-                }
-            }
             self.nominal_obligations(trait_ref.def_id, trait_ref.substs)
         };
 
@@ -571,7 +547,7 @@ impl<'tcx> WfPredicates<'tcx> {
                 }
 
                 ty::FnDef(did, substs) => {
-                    let obligations = self.nominal_obligations(did, substs);
+                    let obligations = self.nominal_obligations_without_const(did, substs);
                     self.out.extend(obligations);
                 }
 
diff --git a/compiler/rustc_traits/Cargo.toml b/compiler/rustc_traits/Cargo.toml
index 951554c77fbb..9474e6df5677 100644
--- a/compiler/rustc_traits/Cargo.toml
+++ b/compiler/rustc_traits/Cargo.toml
@@ -12,9 +12,9 @@ rustc_hir = { path = "../rustc_hir" }
 rustc_index = { path = "../rustc_index" }
 rustc_ast = { path = "../rustc_ast" }
 rustc_span = { path = "../rustc_span" }
-chalk-ir = "0.80.0"
-chalk-engine = "0.80.0"
-chalk-solve = "0.80.0"
+chalk-ir = "0.87.0"
+chalk-engine = "0.87.0"
+chalk-solve = "0.87.0"
 smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
 rustc_infer = { path = "../rustc_infer" }
 rustc_trait_selection = { path = "../rustc_trait_selection" }
diff --git a/compiler/rustc_traits/src/chalk/db.rs b/compiler/rustc_traits/src/chalk/db.rs
index 0de28b826616..d15707e5cedd 100644
--- a/compiler/rustc_traits/src/chalk/db.rs
+++ b/compiler/rustc_traits/src/chalk/db.rs
@@ -142,6 +142,8 @@ impl<'tcx> chalk_solve::RustIrDatabase<RustInterner<'tcx>> for RustIrDatabase<'t
             Some(CoerceUnsized)
         } else if lang_items.dispatch_from_dyn_trait() == Some(def_id) {
             Some(DispatchFromDyn)
+        } else if lang_items.tuple_trait() == Some(def_id) {
+            Some(Tuple)
         } else {
             None
         };
@@ -570,6 +572,7 @@ impl<'tcx> chalk_solve::RustIrDatabase<RustInterner<'tcx>> for RustIrDatabase<'t
             CoerceUnsized => lang_items.coerce_unsized_trait(),
             DiscriminantKind => lang_items.discriminant_kind_trait(),
             DispatchFromDyn => lang_items.dispatch_from_dyn_trait(),
+            Tuple => lang_items.tuple_trait(),
         };
         def_id.map(chalk_ir::TraitId)
     }
@@ -728,16 +731,16 @@ fn bound_vars_for_item<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> SubstsRef<'tcx
         ty::GenericParamDefKind::Lifetime => {
             let br = ty::BoundRegion {
                 var: ty::BoundVar::from_usize(substs.len()),
-                kind: ty::BrAnon(substs.len() as u32),
+                kind: ty::BrAnon(substs.len() as u32, None),
             };
             tcx.mk_region(ty::ReLateBound(ty::INNERMOST, br)).into()
         }
 
         ty::GenericParamDefKind::Const { .. } => tcx
-            .mk_const(ty::ConstS {
-                kind: ty::ConstKind::Bound(ty::INNERMOST, ty::BoundVar::from(param.index)),
-                ty: tcx.type_of(param.def_id),
-            })
+            .mk_const(
+                ty::ConstKind::Bound(ty::INNERMOST, ty::BoundVar::from(param.index)),
+                tcx.type_of(param.def_id),
+            )
             .into(),
     })
 }
diff --git a/compiler/rustc_traits/src/chalk/lowering.rs b/compiler/rustc_traits/src/chalk/lowering.rs
index 45d5ea93d547..25cedefa2612 100644
--- a/compiler/rustc_traits/src/chalk/lowering.rs
+++ b/compiler/rustc_traits/src/chalk/lowering.rs
@@ -498,18 +498,15 @@ impl<'tcx> LowerInto<'tcx, Region<'tcx>> for &chalk_ir::Lifetime<RustInterner<'t
                 ty::DebruijnIndex::from_u32(var.debruijn.depth()),
                 ty::BoundRegion {
                     var: ty::BoundVar::from_usize(var.index),
-                    kind: ty::BrAnon(var.index as u32),
+                    kind: ty::BrAnon(var.index as u32, None),
                 },
             ),
             chalk_ir::LifetimeData::InferenceVar(_var) => unimplemented!(),
             chalk_ir::LifetimeData::Placeholder(p) => ty::RePlaceholder(ty::Placeholder {
                 universe: ty::UniverseIndex::from_usize(p.ui.counter),
-                name: ty::BoundRegionKind::BrAnon(p.idx as u32),
+                name: ty::BoundRegionKind::BrAnon(p.idx as u32, None),
             }),
             chalk_ir::LifetimeData::Static => return interner.tcx.lifetimes.re_static,
-            chalk_ir::LifetimeData::Empty(_) => {
-                bug!("Chalk should not have been passed an empty lifetime.")
-            }
             chalk_ir::LifetimeData::Erased => return interner.tcx.lifetimes.re_erased,
             chalk_ir::LifetimeData::Phantom(void, _) => match *void {},
         };
@@ -546,7 +543,7 @@ impl<'tcx> LowerInto<'tcx, ty::Const<'tcx>> for &chalk_ir::Const<RustInterner<'t
             chalk_ir::ConstValue::Placeholder(_p) => unimplemented!(),
             chalk_ir::ConstValue::Concrete(c) => ty::ConstKind::Value(c.interned),
         };
-        interner.tcx.mk_const(ty::ConstS { ty, kind })
+        interner.tcx.mk_const(kind, ty)
     }
 }
 
@@ -933,7 +930,7 @@ impl<'tcx> TypeVisitor<'tcx> for BoundVarsCollector<'tcx> {
                     }
                 }
 
-                ty::BoundRegionKind::BrAnon(var) => match self.parameters.entry(var) {
+                ty::BoundRegionKind::BrAnon(var, _) => match self.parameters.entry(var) {
                     Entry::Vacant(entry) => {
                         entry.insert(chalk_ir::VariableKind::Lifetime);
                     }
@@ -991,13 +988,13 @@ impl<'a, 'tcx> TypeFolder<'tcx> for NamedBoundVarSubstitutor<'a, 'tcx> {
             ty::ReLateBound(index, br) if index == self.binder_index => match br.kind {
                 ty::BrNamed(def_id, _name) => match self.named_parameters.get(&def_id) {
                     Some(idx) => {
-                        let new_br = ty::BoundRegion { var: br.var, kind: ty::BrAnon(*idx) };
+                        let new_br = ty::BoundRegion { var: br.var, kind: ty::BrAnon(*idx, None) };
                         return self.tcx.mk_region(ty::ReLateBound(index, new_br));
                     }
                     None => panic!("Missing `BrNamed`."),
                 },
                 ty::BrEnv => unimplemented!(),
-                ty::BrAnon(_) => {}
+                ty::BrAnon(..) => {}
             },
             _ => (),
         };
@@ -1072,14 +1069,16 @@ impl<'tcx> TypeFolder<'tcx> for ParamsSubstitutor<'tcx> {
                 Some(idx) => {
                     let br = ty::BoundRegion {
                         var: ty::BoundVar::from_u32(*idx),
-                        kind: ty::BrAnon(*idx),
+                        kind: ty::BrAnon(*idx, None),
                     };
                     self.tcx.mk_region(ty::ReLateBound(self.binder_index, br))
                 }
                 None => {
                     let idx = self.named_regions.len() as u32;
-                    let br =
-                        ty::BoundRegion { var: ty::BoundVar::from_u32(idx), kind: ty::BrAnon(idx) };
+                    let br = ty::BoundRegion {
+                        var: ty::BoundVar::from_u32(idx),
+                        kind: ty::BrAnon(idx, None),
+                    };
                     self.named_regions.insert(_re.def_id, idx);
                     self.tcx.mk_region(ty::ReLateBound(self.binder_index, br))
                 }
@@ -1156,7 +1155,7 @@ impl<'tcx> TypeVisitor<'tcx> for PlaceholdersCollector {
     fn visit_region(&mut self, r: Region<'tcx>) -> ControlFlow<Self::BreakTy> {
         match *r {
             ty::RePlaceholder(p) if p.universe == self.universe_index => {
-                if let ty::BoundRegionKind::BrAnon(anon) = p.name {
+                if let ty::BoundRegionKind::BrAnon(anon, _) = p.name {
                     self.next_anon_region_placeholder = self.next_anon_region_placeholder.max(anon);
                 }
             }
diff --git a/compiler/rustc_traits/src/dropck_outlives.rs b/compiler/rustc_traits/src/dropck_outlives.rs
index d5a8ca5ea784..7b4ad9fea137 100644
--- a/compiler/rustc_traits/src/dropck_outlives.rs
+++ b/compiler/rustc_traits/src/dropck_outlives.rs
@@ -2,20 +2,18 @@ use rustc_data_structures::fx::FxHashSet;
 use rustc_hir::def_id::DefId;
 use rustc_infer::infer::canonical::{Canonical, QueryResponse};
 use rustc_infer::infer::TyCtxtInferExt;
-use rustc_infer::traits::TraitEngineExt as _;
 use rustc_middle::ty::query::Providers;
 use rustc_middle::ty::InternalSubsts;
 use rustc_middle::ty::{self, EarlyBinder, ParamEnvAnd, Ty, TyCtxt};
 use rustc_span::source_map::{Span, DUMMY_SP};
+use rustc_trait_selection::infer::InferCtxtBuilderExt;
 use rustc_trait_selection::traits::query::dropck_outlives::trivial_dropck_outlives;
 use rustc_trait_selection::traits::query::dropck_outlives::{
     DropckConstraint, DropckOutlivesResult,
 };
 use rustc_trait_selection::traits::query::normalize::AtExt;
 use rustc_trait_selection::traits::query::{CanonicalTyGoal, NoSolution};
-use rustc_trait_selection::traits::{
-    Normalized, ObligationCause, TraitEngine, TraitEngineExt as _,
-};
+use rustc_trait_selection::traits::{Normalized, ObligationCause};
 
 pub(crate) fn provide(p: &mut Providers) {
     *p = Providers { dropck_outlives, adt_dtorck_constraint, ..*p };
@@ -27,120 +25,109 @@ fn dropck_outlives<'tcx>(
 ) -> Result<&'tcx Canonical<'tcx, QueryResponse<'tcx, DropckOutlivesResult<'tcx>>>, NoSolution> {
     debug!("dropck_outlives(goal={:#?})", canonical_goal);
 
-    let (ref infcx, goal, canonical_inference_vars) =
-        tcx.infer_ctxt().build_with_canonical(DUMMY_SP, &canonical_goal);
-    let tcx = infcx.tcx;
-    let ParamEnvAnd { param_env, value: for_ty } = goal;
+    tcx.infer_ctxt().enter_canonical_trait_query(&canonical_goal, |ocx, goal| {
+        let tcx = ocx.infcx.tcx;
+        let ParamEnvAnd { param_env, value: for_ty } = goal;
 
-    let mut result = DropckOutlivesResult { kinds: vec![], overflows: vec![] };
+        let mut result = DropckOutlivesResult { kinds: vec![], overflows: vec![] };
 
-    // A stack of types left to process. Each round, we pop
-    // something from the stack and invoke
-    // `dtorck_constraint_for_ty`. This may produce new types that
-    // have to be pushed on the stack. This continues until we have explored
-    // all the reachable types from the type `for_ty`.
-    //
-    // Example: Imagine that we have the following code:
-    //
-    // ```rust
-    // struct A {
-    //     value: B,
-    //     children: Vec<A>,
-    // }
-    //
-    // struct B {
-    //     value: u32
-    // }
-    //
-    // fn f() {
-    //   let a: A = ...;
-    //   ..
-    // } // here, `a` is dropped
-    // ```
-    //
-    // at the point where `a` is dropped, we need to figure out
-    // which types inside of `a` contain region data that may be
-    // accessed by any destructors in `a`. We begin by pushing `A`
-    // onto the stack, as that is the type of `a`. We will then
-    // invoke `dtorck_constraint_for_ty` which will expand `A`
-    // into the types of its fields `(B, Vec<A>)`. These will get
-    // pushed onto the stack. Eventually, expanding `Vec<A>` will
-    // lead to us trying to push `A` a second time -- to prevent
-    // infinite recursion, we notice that `A` was already pushed
-    // once and stop.
-    let mut ty_stack = vec![(for_ty, 0)];
+        // A stack of types left to process. Each round, we pop
+        // something from the stack and invoke
+        // `dtorck_constraint_for_ty`. This may produce new types that
+        // have to be pushed on the stack. This continues until we have explored
+        // all the reachable types from the type `for_ty`.
+        //
+        // Example: Imagine that we have the following code:
+        //
+        // ```rust
+        // struct A {
+        //     value: B,
+        //     children: Vec<A>,
+        // }
+        //
+        // struct B {
+        //     value: u32
+        // }
+        //
+        // fn f() {
+        //   let a: A = ...;
+        //   ..
+        // } // here, `a` is dropped
+        // ```
+        //
+        // at the point where `a` is dropped, we need to figure out
+        // which types inside of `a` contain region data that may be
+        // accessed by any destructors in `a`. We begin by pushing `A`
+        // onto the stack, as that is the type of `a`. We will then
+        // invoke `dtorck_constraint_for_ty` which will expand `A`
+        // into the types of its fields `(B, Vec<A>)`. These will get
+        // pushed onto the stack. Eventually, expanding `Vec<A>` will
+        // lead to us trying to push `A` a second time -- to prevent
+        // infinite recursion, we notice that `A` was already pushed
+        // once and stop.
+        let mut ty_stack = vec![(for_ty, 0)];
 
-    // Set used to detect infinite recursion.
-    let mut ty_set = FxHashSet::default();
+        // Set used to detect infinite recursion.
+        let mut ty_set = FxHashSet::default();
 
-    let mut fulfill_cx = <dyn TraitEngine<'_>>::new(infcx.tcx);
+        let cause = ObligationCause::dummy();
+        let mut constraints = DropckConstraint::empty();
+        while let Some((ty, depth)) = ty_stack.pop() {
+            debug!(
+                "{} kinds, {} overflows, {} ty_stack",
+                result.kinds.len(),
+                result.overflows.len(),
+                ty_stack.len()
+            );
+            dtorck_constraint_for_ty(tcx, DUMMY_SP, for_ty, depth, ty, &mut constraints)?;
 
-    let cause = ObligationCause::dummy();
-    let mut constraints = DropckConstraint::empty();
-    while let Some((ty, depth)) = ty_stack.pop() {
-        debug!(
-            "{} kinds, {} overflows, {} ty_stack",
-            result.kinds.len(),
-            result.overflows.len(),
-            ty_stack.len()
-        );
-        dtorck_constraint_for_ty(tcx, DUMMY_SP, for_ty, depth, ty, &mut constraints)?;
+            // "outlives" represent types/regions that may be touched
+            // by a destructor.
+            result.kinds.append(&mut constraints.outlives);
+            result.overflows.append(&mut constraints.overflows);
 
-        // "outlives" represent types/regions that may be touched
-        // by a destructor.
-        result.kinds.append(&mut constraints.outlives);
-        result.overflows.append(&mut constraints.overflows);
+            // If we have even one overflow, we should stop trying to evaluate further --
+            // chances are, the subsequent overflows for this evaluation won't provide useful
+            // information and will just decrease the speed at which we can emit these errors
+            // (since we'll be printing for just that much longer for the often enormous types
+            // that result here).
+            if !result.overflows.is_empty() {
+                break;
+            }
 
-        // If we have even one overflow, we should stop trying to evaluate further --
-        // chances are, the subsequent overflows for this evaluation won't provide useful
-        // information and will just decrease the speed at which we can emit these errors
-        // (since we'll be printing for just that much longer for the often enormous types
-        // that result here).
-        if !result.overflows.is_empty() {
-            break;
-        }
+            // dtorck types are "types that will get dropped but which
+            // do not themselves define a destructor", more or less. We have
+            // to push them onto the stack to be expanded.
+            for ty in constraints.dtorck_types.drain(..) {
+                let Normalized { value: ty, obligations } =
+                    ocx.infcx.at(&cause, param_env).normalize(ty)?;
+                ocx.register_obligations(obligations);
 
-        // dtorck types are "types that will get dropped but which
-        // do not themselves define a destructor", more or less. We have
-        // to push them onto the stack to be expanded.
-        for ty in constraints.dtorck_types.drain(..) {
-            match infcx.at(&cause, param_env).normalize(ty) {
-                Ok(Normalized { value: ty, obligations }) => {
-                    fulfill_cx.register_predicate_obligations(infcx, obligations);
+                debug!("dropck_outlives: ty from dtorck_types = {:?}", ty);
 
-                    debug!("dropck_outlives: ty from dtorck_types = {:?}", ty);
+                match ty.kind() {
+                    // All parameters live for the duration of the
+                    // function.
+                    ty::Param(..) => {}
 
-                    match ty.kind() {
-                        // All parameters live for the duration of the
-                        // function.
-                        ty::Param(..) => {}
+                    // A projection that we couldn't resolve - it
+                    // might have a destructor.
+                    ty::Projection(..) | ty::Opaque(..) => {
+                        result.kinds.push(ty.into());
+                    }
 
-                        // A projection that we couldn't resolve - it
-                        // might have a destructor.
-                        ty::Projection(..) | ty::Opaque(..) => {
-                            result.kinds.push(ty.into());
-                        }
-
-                        _ => {
-                            if ty_set.insert(ty) {
-                                ty_stack.push((ty, depth + 1));
-                            }
+                    _ => {
+                        if ty_set.insert(ty) {
+                            ty_stack.push((ty, depth + 1));
                         }
                     }
                 }
-
-                // We don't actually expect to fail to normalize.
-                // That implies a WF error somewhere else.
-                Err(NoSolution) => {
-                    return Err(NoSolution);
-                }
             }
         }
-    }
 
-    debug!("dropck_outlives: result = {:#?}", result);
-
-    infcx.make_canonicalized_query_response(canonical_inference_vars, result, &mut *fulfill_cx)
+        debug!("dropck_outlives: result = {:#?}", result);
+        Ok(result)
+    })
 }
 
 /// Returns a set of constraints that needs to be satisfied in
diff --git a/compiler/rustc_traits/src/implied_outlives_bounds.rs b/compiler/rustc_traits/src/implied_outlives_bounds.rs
index 7d36b9558d50..82f6111f6f92 100644
--- a/compiler/rustc_traits/src/implied_outlives_bounds.rs
+++ b/compiler/rustc_traits/src/implied_outlives_bounds.rs
@@ -28,9 +28,9 @@ fn implied_outlives_bounds<'tcx>(
     &'tcx Canonical<'tcx, canonical::QueryResponse<'tcx, Vec<OutlivesBound<'tcx>>>>,
     NoSolution,
 > {
-    tcx.infer_ctxt().enter_canonical_trait_query(&goal, |infcx, _fulfill_cx, key| {
+    tcx.infer_ctxt().enter_canonical_trait_query(&goal, |ocx, key| {
         let (param_env, ty) = key.into_parts();
-        compute_implied_outlives_bounds(&infcx, param_env, ty)
+        compute_implied_outlives_bounds(&ocx.infcx, param_env, ty)
     })
 }
 
diff --git a/compiler/rustc_traits/src/lib.rs b/compiler/rustc_traits/src/lib.rs
index 0da28737f69b..0ffa92f1ad55 100644
--- a/compiler/rustc_traits/src/lib.rs
+++ b/compiler/rustc_traits/src/lib.rs
@@ -3,6 +3,7 @@
 
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
+#![feature(let_chains)]
 #![recursion_limit = "256"]
 
 #[macro_use]
diff --git a/compiler/rustc_traits/src/normalize_projection_ty.rs b/compiler/rustc_traits/src/normalize_projection_ty.rs
index 98bb42c9afda..e805eb428211 100644
--- a/compiler/rustc_traits/src/normalize_projection_ty.rs
+++ b/compiler/rustc_traits/src/normalize_projection_ty.rs
@@ -1,6 +1,5 @@
 use rustc_infer::infer::canonical::{Canonical, QueryResponse};
 use rustc_infer::infer::TyCtxtInferExt;
-use rustc_infer::traits::TraitEngineExt as _;
 use rustc_middle::ty::query::Providers;
 use rustc_middle::ty::{ParamEnvAnd, TyCtxt};
 use rustc_trait_selection::infer::InferCtxtBuilderExt;
@@ -23,8 +22,8 @@ fn normalize_projection_ty<'tcx>(
     tcx.sess.perf_stats.normalize_projection_ty.fetch_add(1, Ordering::Relaxed);
     tcx.infer_ctxt().enter_canonical_trait_query(
         &goal,
-        |infcx, fulfill_cx, ParamEnvAnd { param_env, value: goal }| {
-            let selcx = &mut SelectionContext::new(infcx);
+        |ocx, ParamEnvAnd { param_env, value: goal }| {
+            let selcx = &mut SelectionContext::new(ocx.infcx);
             let cause = ObligationCause::dummy();
             let mut obligations = vec![];
             let answer = traits::normalize_projection_type(
@@ -35,7 +34,7 @@ fn normalize_projection_ty<'tcx>(
                 0,
                 &mut obligations,
             );
-            fulfill_cx.register_predicate_obligations(infcx, obligations);
+            ocx.register_obligations(obligations);
             // FIXME(associated_const_equality): All users of normalize_projection_ty expected
             // a type, but there is the possibility it could've been a const now. Maybe change
             // it to a Term later?
diff --git a/compiler/rustc_traits/src/type_op.rs b/compiler/rustc_traits/src/type_op.rs
index bca7458ed332..98cb3f21555a 100644
--- a/compiler/rustc_traits/src/type_op.rs
+++ b/compiler/rustc_traits/src/type_op.rs
@@ -2,17 +2,14 @@ use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
 use rustc_infer::infer::at::ToTrace;
 use rustc_infer::infer::canonical::{Canonical, QueryResponse};
-use rustc_infer::infer::{DefiningAnchor, InferCtxt, TyCtxtInferExt};
-use rustc_infer::traits::{ObligationCauseCode, TraitEngineExt as _};
+use rustc_infer::infer::{DefiningAnchor, TyCtxtInferExt};
+use rustc_infer::traits::ObligationCauseCode;
 use rustc_middle::ty::query::Providers;
-use rustc_middle::ty::{
-    self, EarlyBinder, FnSig, Lift, PolyFnSig, Ty, TyCtxt, TypeFoldable, Variance,
-};
-use rustc_middle::ty::{GenericArg, UserSelfTy, UserSubsts};
-use rustc_middle::ty::{ParamEnv, ParamEnvAnd, Predicate, ToPredicate};
+use rustc_middle::ty::{self, FnSig, Lift, PolyFnSig, Ty, TyCtxt, TypeFoldable};
+use rustc_middle::ty::{ParamEnvAnd, Predicate, ToPredicate};
+use rustc_middle::ty::{UserSelfTy, UserSubsts};
 use rustc_span::{Span, DUMMY_SP};
 use rustc_trait_selection::infer::InferCtxtBuilderExt;
-use rustc_trait_selection::infer::InferCtxtExt;
 use rustc_trait_selection::traits::query::normalize::AtExt;
 use rustc_trait_selection::traits::query::type_op::ascribe_user_type::AscribeUserType;
 use rustc_trait_selection::traits::query::type_op::eq::Eq;
@@ -20,7 +17,7 @@ use rustc_trait_selection::traits::query::type_op::normalize::Normalize;
 use rustc_trait_selection::traits::query::type_op::prove_predicate::ProvePredicate;
 use rustc_trait_selection::traits::query::type_op::subtype::Subtype;
 use rustc_trait_selection::traits::query::{Fallible, NoSolution};
-use rustc_trait_selection::traits::{Normalized, Obligation, ObligationCause, TraitEngine};
+use rustc_trait_selection::traits::{Normalized, Obligation, ObligationCause, ObligationCtxt};
 use std::fmt;
 use std::iter::zip;
 
@@ -42,17 +39,16 @@ fn type_op_ascribe_user_type<'tcx>(
     tcx: TyCtxt<'tcx>,
     canonicalized: Canonical<'tcx, ParamEnvAnd<'tcx, AscribeUserType<'tcx>>>,
 ) -> Result<&'tcx Canonical<'tcx, QueryResponse<'tcx, ()>>, NoSolution> {
-    tcx.infer_ctxt().enter_canonical_trait_query(&canonicalized, |infcx, fulfill_cx, key| {
-        type_op_ascribe_user_type_with_span(infcx, fulfill_cx, key, None)
+    tcx.infer_ctxt().enter_canonical_trait_query(&canonicalized, |ocx, key| {
+        type_op_ascribe_user_type_with_span(ocx, key, None)
     })
 }
 
 /// The core of the `type_op_ascribe_user_type` query: for diagnostics purposes in NLL HRTB errors,
 /// this query can be re-run to better track the span of the obligation cause, and improve the error
 /// message. Do not call directly unless you're in that very specific context.
-pub fn type_op_ascribe_user_type_with_span<'a, 'tcx: 'a>(
-    infcx: &'a InferCtxt<'tcx>,
-    fulfill_cx: &'a mut dyn TraitEngine<'tcx>,
+pub fn type_op_ascribe_user_type_with_span<'tcx>(
+    ocx: &ObligationCtxt<'_, 'tcx>,
     key: ParamEnvAnd<'tcx, AscribeUserType<'tcx>>,
     span: Option<Span>,
 ) -> Result<(), NoSolution> {
@@ -61,68 +57,50 @@ pub fn type_op_ascribe_user_type_with_span<'a, 'tcx: 'a>(
         "type_op_ascribe_user_type: mir_ty={:?} def_id={:?} user_substs={:?}",
         mir_ty, def_id, user_substs
     );
-
-    let mut cx = AscribeUserTypeCx { infcx, param_env, span: span.unwrap_or(DUMMY_SP), fulfill_cx };
+    let cx = AscribeUserTypeCx { ocx, param_env, span: span.unwrap_or(DUMMY_SP) };
     cx.relate_mir_and_user_ty(mir_ty, def_id, user_substs)?;
     Ok(())
 }
 
 struct AscribeUserTypeCx<'me, 'tcx> {
-    infcx: &'me InferCtxt<'tcx>,
-    param_env: ParamEnv<'tcx>,
+    ocx: &'me ObligationCtxt<'me, 'tcx>,
+    param_env: ty::ParamEnv<'tcx>,
     span: Span,
-    fulfill_cx: &'me mut dyn TraitEngine<'tcx>,
 }
 
 impl<'me, 'tcx> AscribeUserTypeCx<'me, 'tcx> {
-    fn normalize<T>(&mut self, value: T) -> T
+    fn normalize<T>(&self, value: T) -> T
     where
         T: TypeFoldable<'tcx>,
     {
         self.normalize_with_cause(value, ObligationCause::misc(self.span, hir::CRATE_HIR_ID))
     }
 
-    fn normalize_with_cause<T>(&mut self, value: T, cause: ObligationCause<'tcx>) -> T
+    fn normalize_with_cause<T>(&self, value: T, cause: ObligationCause<'tcx>) -> T
     where
         T: TypeFoldable<'tcx>,
     {
-        self.infcx
-            .partially_normalize_associated_types_in(cause, self.param_env, value)
-            .into_value_registering_obligations(self.infcx, self.fulfill_cx)
+        self.ocx.normalize(cause, self.param_env, value)
     }
 
-    fn relate<T>(&mut self, a: T, variance: Variance, b: T) -> Result<(), NoSolution>
+    fn eq<T>(&self, a: T, b: T) -> Result<(), NoSolution>
     where
         T: ToTrace<'tcx>,
     {
-        self.infcx
-            .at(&ObligationCause::dummy_with_span(self.span), self.param_env)
-            .relate(a, variance, b)?
-            .into_value_registering_obligations(self.infcx, self.fulfill_cx);
-        Ok(())
+        Ok(self.ocx.eq(&ObligationCause::dummy_with_span(self.span), self.param_env, a, b)?)
     }
 
-    fn prove_predicate(&mut self, predicate: Predicate<'tcx>, cause: ObligationCause<'tcx>) {
-        self.fulfill_cx.register_predicate_obligation(
-            self.infcx,
-            Obligation::new(cause, self.param_env, predicate),
-        );
+    fn prove_predicate(&self, predicate: Predicate<'tcx>, cause: ObligationCause<'tcx>) {
+        self.ocx.register_obligation(Obligation::new(cause, self.param_env, predicate));
     }
 
     fn tcx(&self) -> TyCtxt<'tcx> {
-        self.infcx.tcx
-    }
-
-    fn subst<T>(&self, value: T, substs: &[GenericArg<'tcx>]) -> T
-    where
-        T: TypeFoldable<'tcx>,
-    {
-        EarlyBinder(value).subst(self.tcx(), substs)
+        self.ocx.infcx.tcx
     }
 
     #[instrument(level = "debug", skip(self))]
     fn relate_mir_and_user_ty(
-        &mut self,
+        &self,
         mir_ty: Ty<'tcx>,
         def_id: DefId,
         user_substs: UserSubsts<'tcx>,
@@ -130,20 +108,18 @@ impl<'me, 'tcx> AscribeUserTypeCx<'me, 'tcx> {
         let UserSubsts { user_self_ty, substs } = user_substs;
         let tcx = self.tcx();
 
-        let ty = tcx.type_of(def_id);
-        let ty = self.subst(ty, substs);
+        let ty = tcx.bound_type_of(def_id).subst(tcx, substs);
         let ty = self.normalize(ty);
         debug!("relate_type_and_user_type: ty of def-id is {:?}", ty);
 
-        self.relate(mir_ty, Variance::Invariant, ty)?;
+        self.eq(mir_ty, ty)?;
 
         // Prove the predicates coming along with `def_id`.
         //
         // Also, normalize the `instantiated_predicates`
         // because otherwise we wind up with duplicate "type
         // outlives" error messages.
-        let instantiated_predicates =
-            self.tcx().predicates_of(def_id).instantiate(self.tcx(), substs);
+        let instantiated_predicates = tcx.predicates_of(def_id).instantiate(tcx, substs);
 
         let cause = ObligationCause::dummy_with_span(self.span);
 
@@ -163,15 +139,14 @@ impl<'me, 'tcx> AscribeUserTypeCx<'me, 'tcx> {
         }
 
         if let Some(UserSelfTy { impl_def_id, self_ty }) = user_self_ty {
-            let impl_self_ty = self.tcx().type_of(impl_def_id);
-            let impl_self_ty = self.subst(impl_self_ty, &substs);
+            let impl_self_ty = tcx.bound_type_of(impl_def_id).subst(tcx, substs);
             let impl_self_ty = self.normalize(impl_self_ty);
 
-            self.relate(self_ty, Variance::Invariant, impl_self_ty)?;
+            self.eq(self_ty, impl_self_ty)?;
 
             self.prove_predicate(
                 ty::Binder::dummy(ty::PredicateKind::WellFormed(impl_self_ty.into()))
-                    .to_predicate(self.tcx()),
+                    .to_predicate(tcx),
                 cause.clone(),
             );
         }
@@ -188,7 +163,7 @@ impl<'me, 'tcx> AscribeUserTypeCx<'me, 'tcx> {
         // type were ill-formed but did not appear in `ty`,
         // which...could happen with normalization...
         self.prove_predicate(
-            ty::Binder::dummy(ty::PredicateKind::WellFormed(ty.into())).to_predicate(self.tcx()),
+            ty::Binder::dummy(ty::PredicateKind::WellFormed(ty.into())).to_predicate(tcx),
             cause,
         );
         Ok(())
@@ -199,19 +174,14 @@ fn type_op_eq<'tcx>(
     tcx: TyCtxt<'tcx>,
     canonicalized: Canonical<'tcx, ParamEnvAnd<'tcx, Eq<'tcx>>>,
 ) -> Result<&'tcx Canonical<'tcx, QueryResponse<'tcx, ()>>, NoSolution> {
-    tcx.infer_ctxt().enter_canonical_trait_query(&canonicalized, |infcx, fulfill_cx, key| {
+    tcx.infer_ctxt().enter_canonical_trait_query(&canonicalized, |ocx, key| {
         let (param_env, Eq { a, b }) = key.into_parts();
-        infcx
-            .at(&ObligationCause::dummy(), param_env)
-            .eq(a, b)?
-            .into_value_registering_obligations(infcx, fulfill_cx);
-        Ok(())
+        Ok(ocx.eq(&ObligationCause::dummy(), param_env, a, b)?)
     })
 }
 
 fn type_op_normalize<'tcx, T>(
-    infcx: &InferCtxt<'tcx>,
-    fulfill_cx: &mut dyn TraitEngine<'tcx>,
+    ocx: &ObligationCtxt<'_, 'tcx>,
     key: ParamEnvAnd<'tcx, Normalize<T>>,
 ) -> Fallible<T>
 where
@@ -219,8 +189,8 @@ where
 {
     let (param_env, Normalize { value }) = key.into_parts();
     let Normalized { value, obligations } =
-        infcx.at(&ObligationCause::dummy(), param_env).normalize(value)?;
-    fulfill_cx.register_predicate_obligations(infcx, obligations);
+        ocx.infcx.at(&ObligationCause::dummy(), param_env).normalize(value)?;
+    ocx.register_obligations(obligations);
     Ok(value)
 }
 
@@ -256,13 +226,9 @@ fn type_op_subtype<'tcx>(
     tcx: TyCtxt<'tcx>,
     canonicalized: Canonical<'tcx, ParamEnvAnd<'tcx, Subtype<'tcx>>>,
 ) -> Result<&'tcx Canonical<'tcx, QueryResponse<'tcx, ()>>, NoSolution> {
-    tcx.infer_ctxt().enter_canonical_trait_query(&canonicalized, |infcx, fulfill_cx, key| {
+    tcx.infer_ctxt().enter_canonical_trait_query(&canonicalized, |ocx, key| {
         let (param_env, Subtype { sub, sup }) = key.into_parts();
-        infcx
-            .at(&ObligationCause::dummy(), param_env)
-            .sup(sup, sub)?
-            .into_value_registering_obligations(infcx, fulfill_cx);
-        Ok(())
+        Ok(ocx.sup(&ObligationCause::dummy(), param_env, sup, sub)?)
     })
 }
 
@@ -274,8 +240,8 @@ fn type_op_prove_predicate<'tcx>(
     // impl-trait/issue-99642.rs
     tcx.infer_ctxt().with_opaque_type_inference(DefiningAnchor::Bubble).enter_canonical_trait_query(
         &canonicalized,
-        |infcx, fulfill_cx, key| {
-            type_op_prove_predicate_with_cause(infcx, fulfill_cx, key, ObligationCause::dummy());
+        |ocx, key| {
+            type_op_prove_predicate_with_cause(ocx, key, ObligationCause::dummy());
             Ok(())
         },
     )
@@ -284,12 +250,11 @@ fn type_op_prove_predicate<'tcx>(
 /// The core of the `type_op_prove_predicate` query: for diagnostics purposes in NLL HRTB errors,
 /// this query can be re-run to better track the span of the obligation cause, and improve the error
 /// message. Do not call directly unless you're in that very specific context.
-pub fn type_op_prove_predicate_with_cause<'a, 'tcx: 'a>(
-    infcx: &'a InferCtxt<'tcx>,
-    fulfill_cx: &'a mut dyn TraitEngine<'tcx>,
+pub fn type_op_prove_predicate_with_cause<'tcx>(
+    ocx: &ObligationCtxt<'_, 'tcx>,
     key: ParamEnvAnd<'tcx, ProvePredicate<'tcx>>,
     cause: ObligationCause<'tcx>,
 ) {
     let (param_env, ProvePredicate { predicate }) = key.into_parts();
-    fulfill_cx.register_predicate_obligation(infcx, Obligation::new(cause, param_env, predicate));
+    ocx.register_obligation(Obligation::new(cause, param_env, predicate));
 }
diff --git a/compiler/rustc_transmute/src/layout/tree.rs b/compiler/rustc_transmute/src/layout/tree.rs
index acd4fa63d782..30e20ba6f586 100644
--- a/compiler/rustc_transmute/src/layout/tree.rs
+++ b/compiler/rustc_transmute/src/layout/tree.rs
@@ -284,7 +284,8 @@ pub(crate) mod rustc {
                 }
 
                 ty::Array(ty, len) => {
-                    let len = len.try_eval_usize(tcx, ParamEnv::reveal_all()).unwrap();
+                    let len =
+                        len.try_eval_usize(tcx, ParamEnv::reveal_all()).ok_or(Err::Unspecified)?;
                     let elt = Tree::from_ty(*ty, tcx)?;
                     Ok(std::iter::repeat(elt)
                         .take(len as usize)
@@ -435,8 +436,8 @@ pub(crate) mod rustc {
 
             // finally: padding
             let padding_span = trace_span!("adding trailing padding").entered();
-            let padding_needed = layout_summary.total_size - variant_layout.size();
-            if padding_needed > 0 {
+            if layout_summary.total_size > variant_layout.size() {
+                let padding_needed = layout_summary.total_size - variant_layout.size();
                 tree = tree.then(Self::padding(padding_needed));
             };
             drop(padding_span);
diff --git a/compiler/rustc_transmute/src/lib.rs b/compiler/rustc_transmute/src/lib.rs
index f7cc94e53146..384d03106b1e 100644
--- a/compiler/rustc_transmute/src/lib.rs
+++ b/compiler/rustc_transmute/src/lib.rs
@@ -122,7 +122,7 @@ mod rustc {
 
             let c = c.eval(tcx, param_env);
 
-            if let Some(err) = c.error_reported() {
+            if let Err(err) = c.error_reported() {
                 return Some(Self {
                     alignment: true,
                     lifetimes: true,
diff --git a/compiler/rustc_ty_utils/src/assoc.rs b/compiler/rustc_ty_utils/src/assoc.rs
index 3e2553c425ed..424b52309d3a 100644
--- a/compiler/rustc_ty_utils/src/assoc.rs
+++ b/compiler/rustc_ty_utils/src/assoc.rs
@@ -17,10 +17,10 @@ fn associated_item_def_ids(tcx: TyCtxt<'_>, def_id: DefId) -> &[DefId] {
     let item = tcx.hir().expect_item(def_id.expect_local());
     match item.kind {
         hir::ItemKind::Trait(.., ref trait_item_refs) => tcx.arena.alloc_from_iter(
-            trait_item_refs.iter().map(|trait_item_ref| trait_item_ref.id.def_id.to_def_id()),
+            trait_item_refs.iter().map(|trait_item_ref| trait_item_ref.id.owner_id.to_def_id()),
         ),
         hir::ItemKind::Impl(ref impl_) => tcx.arena.alloc_from_iter(
-            impl_.items.iter().map(|impl_item_ref| impl_item_ref.id.def_id.to_def_id()),
+            impl_.items.iter().map(|impl_item_ref| impl_item_ref.id.owner_id.to_def_id()),
         ),
         hir::ItemKind::TraitAlias(..) => &[],
         _ => span_bug!(item.span, "associated_item_def_ids: not impl or trait"),
@@ -46,7 +46,7 @@ fn associated_item(tcx: TyCtxt<'_>, def_id: DefId) -> ty::AssocItem {
     match parent_item.kind {
         hir::ItemKind::Impl(ref impl_) => {
             if let Some(impl_item_ref) =
-                impl_.items.iter().find(|i| i.id.def_id.to_def_id() == def_id)
+                impl_.items.iter().find(|i| i.id.owner_id.to_def_id() == def_id)
             {
                 let assoc_item = associated_item_from_impl_item_ref(impl_item_ref);
                 debug_assert_eq!(assoc_item.def_id, def_id);
@@ -56,7 +56,7 @@ fn associated_item(tcx: TyCtxt<'_>, def_id: DefId) -> ty::AssocItem {
 
         hir::ItemKind::Trait(.., ref trait_item_refs) => {
             if let Some(trait_item_ref) =
-                trait_item_refs.iter().find(|i| i.id.def_id.to_def_id() == def_id)
+                trait_item_refs.iter().find(|i| i.id.owner_id.to_def_id() == def_id)
             {
                 let assoc_item = associated_item_from_trait_item_ref(trait_item_ref);
                 debug_assert_eq!(assoc_item.def_id, def_id);
@@ -75,7 +75,7 @@ fn associated_item(tcx: TyCtxt<'_>, def_id: DefId) -> ty::AssocItem {
 }
 
 fn associated_item_from_trait_item_ref(trait_item_ref: &hir::TraitItemRef) -> ty::AssocItem {
-    let def_id = trait_item_ref.id.def_id;
+    let owner_id = trait_item_ref.id.owner_id;
     let (kind, has_self) = match trait_item_ref.kind {
         hir::AssocItemKind::Const => (ty::AssocKind::Const, false),
         hir::AssocItemKind::Fn { has_self } => (ty::AssocKind::Fn, has_self),
@@ -85,15 +85,15 @@ fn associated_item_from_trait_item_ref(trait_item_ref: &hir::TraitItemRef) -> ty
     ty::AssocItem {
         name: trait_item_ref.ident.name,
         kind,
-        def_id: def_id.to_def_id(),
-        trait_item_def_id: Some(def_id.to_def_id()),
+        def_id: owner_id.to_def_id(),
+        trait_item_def_id: Some(owner_id.to_def_id()),
         container: ty::TraitContainer,
         fn_has_self_parameter: has_self,
     }
 }
 
 fn associated_item_from_impl_item_ref(impl_item_ref: &hir::ImplItemRef) -> ty::AssocItem {
-    let def_id = impl_item_ref.id.def_id;
+    let def_id = impl_item_ref.id.owner_id;
     let (kind, has_self) = match impl_item_ref.kind {
         hir::AssocItemKind::Const => (ty::AssocKind::Const, false),
         hir::AssocItemKind::Fn { has_self } => (ty::AssocKind::Fn, has_self),
diff --git a/compiler/rustc_ty_utils/src/consts.rs b/compiler/rustc_ty_utils/src/consts.rs
index e057bb668250..cb41c4f94e2e 100644
--- a/compiler/rustc_ty_utils/src/consts.rs
+++ b/compiler/rustc_ty_utils/src/consts.rs
@@ -33,7 +33,7 @@ pub(crate) fn destructure_const<'tcx>(
             // construct the consts for the elements of the array/slice
             let field_consts = branches
                 .iter()
-                .map(|b| tcx.mk_const(ty::ConstS { kind: ty::ConstKind::Value(*b), ty: *inner_ty }))
+                .map(|b| tcx.mk_const(ty::ConstKind::Value(*b), *inner_ty))
                 .collect::<Vec<_>>();
             debug!(?field_consts);
 
@@ -52,10 +52,7 @@ pub(crate) fn destructure_const<'tcx>(
 
             for (field, field_valtree) in iter::zip(fields, branches) {
                 let field_ty = field.ty(tcx, substs);
-                let field_const = tcx.mk_const(ty::ConstS {
-                    kind: ty::ConstKind::Value(*field_valtree),
-                    ty: field_ty,
-                });
+                let field_const = tcx.mk_const(ty::ConstKind::Value(*field_valtree), field_ty);
                 field_consts.push(field_const);
             }
             debug!(?field_consts);
@@ -65,10 +62,7 @@ pub(crate) fn destructure_const<'tcx>(
         ty::Tuple(elem_tys) => {
             let fields = iter::zip(*elem_tys, branches)
                 .map(|(elem_ty, elem_valtree)| {
-                    tcx.mk_const(ty::ConstS {
-                        kind: ty::ConstKind::Value(*elem_valtree),
-                        ty: elem_ty,
-                    })
+                    tcx.mk_const(ty::ConstKind::Value(*elem_valtree), elem_ty)
                 })
                 .collect::<Vec<_>>();
 
@@ -241,7 +235,9 @@ impl<'a, 'tcx> AbstractConstBuilder<'a, 'tcx> {
                     neg,
                 }) {
                     Ok(c) => c,
-                    Err(LitToConstError::Reported) => self.tcx.const_error(node.ty),
+                    Err(LitToConstError::Reported(guar)) => {
+                        self.tcx.const_error_with_guaranteed(node.ty, guar)
+                    }
                     Err(LitToConstError::TypeError) => {
                         bug!("encountered type error in lit_to_const")
                     }
@@ -261,17 +257,13 @@ impl<'a, 'tcx> AbstractConstBuilder<'a, 'tcx> {
                 let uneval =
                     ty::UnevaluatedConst::new(ty::WithOptConstParam::unknown(def_id), substs);
 
-                let constant = self
-                    .tcx
-                    .mk_const(ty::ConstS { kind: ty::ConstKind::Unevaluated(uneval), ty: node.ty });
+                let constant = self.tcx.mk_const(ty::ConstKind::Unevaluated(uneval), node.ty);
 
                 self.nodes.push(Node::Leaf(constant))
             }
 
             ExprKind::ConstParam { param, .. } => {
-                let const_param = self
-                    .tcx
-                    .mk_const(ty::ConstS { kind: ty::ConstKind::Param(*param), ty: node.ty });
+                let const_param = self.tcx.mk_const(ty::ConstKind::Param(*param), node.ty);
                 self.nodes.push(Node::Leaf(const_param))
             }
 
diff --git a/compiler/rustc_ty_utils/src/instance.rs b/compiler/rustc_ty_utils/src/instance.rs
index 416c1ec510b0..6436713b3881 100644
--- a/compiler/rustc_ty_utils/src/instance.rs
+++ b/compiler/rustc_ty_utils/src/instance.rs
@@ -4,7 +4,7 @@ use rustc_infer::infer::TyCtxtInferExt;
 use rustc_middle::traits::CodegenObligationError;
 use rustc_middle::ty::subst::SubstsRef;
 use rustc_middle::ty::{self, Instance, TyCtxt, TypeVisitable};
-use rustc_span::{sym, DUMMY_SP};
+use rustc_span::sym;
 use rustc_trait_selection::traits;
 use traits::{translate_substs, Reveal};
 
@@ -236,7 +236,7 @@ fn resolve_associated_item<'tcx>(
                 if name == sym::clone {
                     let self_ty = trait_ref.self_ty();
 
-                    let is_copy = self_ty.is_copy_modulo_regions(tcx.at(DUMMY_SP), param_env);
+                    let is_copy = self_ty.is_copy_modulo_regions(tcx, param_env);
                     match self_ty.kind() {
                         _ if is_copy => (),
                         ty::Generator(..)
diff --git a/compiler/rustc_ty_utils/src/layout.rs b/compiler/rustc_ty_utils/src/layout.rs
index 345911f4309a..b59be0a0ea79 100644
--- a/compiler/rustc_ty_utils/src/layout.rs
+++ b/compiler/rustc_ty_utils/src/layout.rs
@@ -399,7 +399,7 @@ fn layout_of_uncached<'tcx>(
             }
 
             let pointee = tcx.normalize_erasing_regions(param_env, pointee);
-            if pointee.is_sized(tcx.at(DUMMY_SP), param_env) {
+            if pointee.is_sized(tcx, param_env) {
                 return Ok(tcx.intern_layout(LayoutS::scalar(cx, data_ptr)));
             }
 
@@ -668,7 +668,7 @@ fn layout_of_uncached<'tcx>(
                 let mut abi = Abi::Aggregate { sized: true };
                 let index = VariantIdx::new(0);
                 for field in &variants[index] {
-                    assert!(!field.is_unsized());
+                    assert!(field.is_sized());
                     align = align.max(field.align);
 
                     // If all non-ZST fields have the same ABI, forward this ABI
@@ -755,8 +755,7 @@ fn layout_of_uncached<'tcx>(
                 } else {
                     let param_env = tcx.param_env(def.did());
                     let last_field = def.variant(v).fields.last().unwrap();
-                    let always_sized =
-                        tcx.type_of(last_field.did).is_sized(tcx.at(DUMMY_SP), param_env);
+                    let always_sized = tcx.type_of(last_field.did).is_sized(tcx, param_env);
                     if !always_sized { StructKind::MaybeUnsized } else { StructKind::AlwaysSized }
                 };
 
diff --git a/compiler/rustc_ty_utils/src/needs_drop.rs b/compiler/rustc_ty_utils/src/needs_drop.rs
index d390a3081530..024dcd591bd7 100644
--- a/compiler/rustc_ty_utils/src/needs_drop.rs
+++ b/compiler/rustc_ty_utils/src/needs_drop.rs
@@ -109,7 +109,7 @@ where
 
             for component in components {
                 match *component.kind() {
-                    _ if component.is_copy_modulo_regions(tcx.at(DUMMY_SP), self.param_env) => (),
+                    _ if component.is_copy_modulo_regions(tcx, self.param_env) => (),
 
                     ty::Closure(_, substs) => {
                         queue_type(self, substs.as_closure().tupled_upvars_ty());
diff --git a/compiler/rustc_ty_utils/src/ty.rs b/compiler/rustc_ty_utils/src/ty.rs
index 196d70614e7c..99d3bda6ebff 100644
--- a/compiler/rustc_ty_utils/src/ty.rs
+++ b/compiler/rustc_ty_utils/src/ty.rs
@@ -137,10 +137,82 @@ fn param_env(tcx: TyCtxt<'_>, def_id: DefId) -> ty::ParamEnv<'_> {
     let local_did = def_id.as_local();
     let hir_id = local_did.map(|def_id| tcx.hir().local_def_id_to_hir_id(def_id));
 
+    // FIXME(consts): This is not exactly in line with the constness query.
+    let constness = match hir_id {
+        Some(hir_id) => match tcx.hir().get(hir_id) {
+            hir::Node::TraitItem(hir::TraitItem { kind: hir::TraitItemKind::Fn(..), .. })
+                if tcx.is_const_default_method(def_id) =>
+            {
+                hir::Constness::Const
+            }
+
+            hir::Node::Item(hir::Item { kind: hir::ItemKind::Const(..), .. })
+            | hir::Node::Item(hir::Item { kind: hir::ItemKind::Static(..), .. })
+            | hir::Node::TraitItem(hir::TraitItem {
+                kind: hir::TraitItemKind::Const(..), ..
+            })
+            | hir::Node::AnonConst(_)
+            | hir::Node::ImplItem(hir::ImplItem { kind: hir::ImplItemKind::Const(..), .. })
+            | hir::Node::ImplItem(hir::ImplItem {
+                kind:
+                    hir::ImplItemKind::Fn(
+                        hir::FnSig {
+                            header: hir::FnHeader { constness: hir::Constness::Const, .. },
+                            ..
+                        },
+                        ..,
+                    ),
+                ..
+            }) => hir::Constness::Const,
+
+            hir::Node::ImplItem(hir::ImplItem {
+                kind: hir::ImplItemKind::Type(..) | hir::ImplItemKind::Fn(..),
+                ..
+            }) => {
+                let parent_hir_id = tcx.hir().get_parent_node(hir_id);
+                match tcx.hir().get(parent_hir_id) {
+                    hir::Node::Item(hir::Item {
+                        kind: hir::ItemKind::Impl(hir::Impl { constness, .. }),
+                        ..
+                    }) => *constness,
+                    _ => span_bug!(
+                        tcx.def_span(parent_hir_id.owner),
+                        "impl item's parent node is not an impl",
+                    ),
+                }
+            }
+
+            hir::Node::Item(hir::Item {
+                kind:
+                    hir::ItemKind::Fn(hir::FnSig { header: hir::FnHeader { constness, .. }, .. }, ..),
+                ..
+            })
+            | hir::Node::TraitItem(hir::TraitItem {
+                kind:
+                    hir::TraitItemKind::Fn(
+                        hir::FnSig { header: hir::FnHeader { constness, .. }, .. },
+                        ..,
+                    ),
+                ..
+            })
+            | hir::Node::Item(hir::Item {
+                kind: hir::ItemKind::Impl(hir::Impl { constness, .. }),
+                ..
+            }) => *constness,
+
+            _ => hir::Constness::NotConst,
+        },
+        // FIXME(consts): It's suspicious that a param-env for a foreign item
+        // will always have NotConst param-env, though we don't typically use
+        // that param-env for anything meaningful right now, so it's likely
+        // not an issue.
+        None => hir::Constness::NotConst,
+    };
+
     let unnormalized_env = ty::ParamEnv::new(
         tcx.intern_predicates(&predicates),
         traits::Reveal::UserFacing,
-        tcx.constness(def_id),
+        constness,
     );
 
     let body_id =
@@ -341,7 +413,7 @@ fn issue33140_self_ty(tcx: TyCtxt<'_>, def_id: DefId) -> Option<Ty<'_>> {
 /// Check if a function is async.
 fn asyncness(tcx: TyCtxt<'_>, def_id: DefId) -> hir::IsAsync {
     let node = tcx.hir().get_by_def_id(def_id.expect_local());
-    if let Some(fn_kind) = node.fn_kind() { fn_kind.asyncness() } else { hir::IsAsync::NotAsync }
+    node.fn_sig().map_or(hir::IsAsync::NotAsync, |sig| sig.header.asyncness)
 }
 
 /// Don't call this directly: use ``tcx.conservative_is_privately_uninhabited`` instead.
diff --git a/compiler/rustc_type_ir/src/lib.rs b/compiler/rustc_type_ir/src/lib.rs
index 7fbe78aa5235..7c3eb4efbc98 100644
--- a/compiler/rustc_type_ir/src/lib.rs
+++ b/compiler/rustc_type_ir/src/lib.rs
@@ -45,7 +45,7 @@ pub trait Interner {
     type BoundTy: Clone + Debug + Hash + PartialEq + Eq + PartialOrd + Ord;
     type PlaceholderType: Clone + Debug + Hash + PartialEq + Eq + PartialOrd + Ord;
     type InferTy: Clone + Debug + Hash + PartialEq + Eq + PartialOrd + Ord;
-    type DelaySpanBugEmitted: Clone + Debug + Hash + PartialEq + Eq + PartialOrd + Ord;
+    type ErrorGuaranteed: Clone + Debug + Hash + PartialEq + Eq + PartialOrd + Ord;
     type PredicateKind: Clone + Debug + Hash + PartialEq + Eq;
     type AllocId: Clone + Debug + Hash + PartialEq + Eq + PartialOrd + Ord;
 
diff --git a/compiler/rustc_type_ir/src/sty.rs b/compiler/rustc_type_ir/src/sty.rs
index a4fb1480fa44..02cbb2e858f8 100644
--- a/compiler/rustc_type_ir/src/sty.rs
+++ b/compiler/rustc_type_ir/src/sty.rs
@@ -217,7 +217,7 @@ pub enum TyKind<I: Interner> {
 
     /// A placeholder for a type which could not be computed; this is
     /// propagated to avoid useless error messages.
-    Error(I::DelaySpanBugEmitted),
+    Error(I::ErrorGuaranteed),
 }
 
 impl<I: Interner> TyKind<I> {
@@ -626,7 +626,7 @@ impl<I: Interner> fmt::Debug for TyKind<I> {
 // This is manually implemented because a derive would require `I: Encodable`
 impl<I: Interner, E: TyEncoder> Encodable<E> for TyKind<I>
 where
-    I::DelaySpanBugEmitted: Encodable<E>,
+    I::ErrorGuaranteed: Encodable<E>,
     I::AdtDef: Encodable<E>,
     I::SubstsRef: Encodable<E>,
     I::DefId: Encodable<E>,
@@ -645,7 +645,6 @@ where
     I::BoundTy: Encodable<E>,
     I::PlaceholderType: Encodable<E>,
     I::InferTy: Encodable<E>,
-    I::DelaySpanBugEmitted: Encodable<E>,
     I::PredicateKind: Encodable<E>,
     I::AllocId: Encodable<E>,
 {
@@ -744,7 +743,7 @@ where
 // This is manually implemented because a derive would require `I: Decodable`
 impl<I: Interner, D: TyDecoder<I = I>> Decodable<D> for TyKind<I>
 where
-    I::DelaySpanBugEmitted: Decodable<D>,
+    I::ErrorGuaranteed: Decodable<D>,
     I::AdtDef: Decodable<D>,
     I::SubstsRef: Decodable<D>,
     I::DefId: Decodable<D>,
@@ -763,7 +762,6 @@ where
     I::BoundTy: Decodable<D>,
     I::PlaceholderType: Decodable<D>,
     I::InferTy: Decodable<D>,
-    I::DelaySpanBugEmitted: Decodable<D>,
     I::PredicateKind: Decodable<D>,
     I::AllocId: Decodable<D>,
 {
@@ -829,7 +827,7 @@ where
     I::ParamTy: HashStable<CTX>,
     I::PlaceholderType: HashStable<CTX>,
     I::InferTy: HashStable<CTX>,
-    I::DelaySpanBugEmitted: HashStable<CTX>,
+    I::ErrorGuaranteed: HashStable<CTX>,
 {
     #[inline]
     fn hash_stable(
diff --git a/config.toml.example b/config.toml.example
index a46813e4d7a3..c94a27b12a3a 100644
--- a/config.toml.example
+++ b/config.toml.example
@@ -87,9 +87,10 @@ changelog-seen = 2
 # this flag will indicate that this version check should not be done.
 #version-check = true
 
-# Link libstdc++ statically into the rustc_llvm instead of relying on a
-# dynamic version to be available.
-#static-libstdcpp = true
+# When true, link libstdc++ statically into the rustc_llvm.
+# This is useful if you don't want to use the dynamic version of that
+# library provided by LLVM.
+#static-libstdcpp = false
 
 # Whether to use Ninja to build LLVM. This runs much faster than make.
 #ninja = true
@@ -291,10 +292,6 @@ changelog-seen = 2
 # on this runtime, such as `-C profile-generate` or `-C instrument-coverage`).
 #profiler = false
 
-# Use the optimized LLVM C intrinsics for `compiler_builtins`, rather than Rust intrinsics.
-# Requires the LLVM submodule to be managed by bootstrap (i.e. not external).
-#optimized-compiler-builtins = false
-
 # Indicates whether the native libraries linked into Cargo will be statically
 # linked or not.
 #cargo-native-static = false
diff --git a/library/alloc/src/alloc.rs b/library/alloc/src/alloc.rs
index 8187517ccfbb..e5fbfc55761f 100644
--- a/library/alloc/src/alloc.rs
+++ b/library/alloc/src/alloc.rs
@@ -28,20 +28,16 @@ extern "Rust" {
     // The rustc fork of LLVM 14 and earlier also special-cases these function names to be able to optimize them
     // like `malloc`, `realloc`, and `free`, respectively.
     #[rustc_allocator]
-    #[cfg_attr(not(bootstrap), rustc_nounwind)]
-    #[cfg_attr(bootstrap, rustc_allocator_nounwind)]
+    #[rustc_nounwind]
     fn __rust_alloc(size: usize, align: usize) -> *mut u8;
     #[rustc_deallocator]
-    #[cfg_attr(not(bootstrap), rustc_nounwind)]
-    #[cfg_attr(bootstrap, rustc_allocator_nounwind)]
+    #[rustc_nounwind]
     fn __rust_dealloc(ptr: *mut u8, size: usize, align: usize);
     #[rustc_reallocator]
-    #[cfg_attr(not(bootstrap), rustc_nounwind)]
-    #[cfg_attr(bootstrap, rustc_allocator_nounwind)]
+    #[rustc_nounwind]
     fn __rust_realloc(ptr: *mut u8, old_size: usize, align: usize, new_size: usize) -> *mut u8;
     #[rustc_allocator_zeroed]
-    #[cfg_attr(not(bootstrap), rustc_nounwind)]
-    #[cfg_attr(bootstrap, rustc_allocator_nounwind)]
+    #[rustc_nounwind]
     fn __rust_alloc_zeroed(size: usize, align: usize) -> *mut u8;
 }
 
@@ -402,19 +398,18 @@ pub use std::alloc::handle_alloc_error;
 #[allow(unused_attributes)]
 #[unstable(feature = "alloc_internals", issue = "none")]
 pub mod __alloc_error_handler {
-    use crate::alloc::Layout;
-
-    // called via generated `__rust_alloc_error_handler`
-
-    // if there is no `#[alloc_error_handler]`
+    // called via generated `__rust_alloc_error_handler` if there is no
+    // `#[alloc_error_handler]`.
     #[rustc_std_internal_symbol]
     pub unsafe fn __rdl_oom(size: usize, _align: usize) -> ! {
         panic!("memory allocation of {size} bytes failed")
     }
 
-    // if there is an `#[alloc_error_handler]`
+    #[cfg(bootstrap)]
     #[rustc_std_internal_symbol]
     pub unsafe fn __rg_oom(size: usize, align: usize) -> ! {
+        use crate::alloc::Layout;
+
         let layout = unsafe { Layout::from_size_align_unchecked(size, align) };
         extern "Rust" {
             #[lang = "oom"]
diff --git a/library/alloc/src/alloc/tests.rs b/library/alloc/src/alloc/tests.rs
index b2f0194599b2..1a5938fd34cf 100644
--- a/library/alloc/src/alloc/tests.rs
+++ b/library/alloc/src/alloc/tests.rs
@@ -22,7 +22,6 @@ fn allocate_zeroed() {
 }
 
 #[bench]
-#[cfg_attr(miri, ignore)] // isolated Miri does not support benchmarks
 fn alloc_owned_small(b: &mut Bencher) {
     b.iter(|| {
         let _: Box<_> = Box::new(10);
diff --git a/library/alloc/src/boxed.rs b/library/alloc/src/boxed.rs
index b7e7d5a38a5b..97186589a4f4 100644
--- a/library/alloc/src/boxed.rs
+++ b/library/alloc/src/boxed.rs
@@ -158,6 +158,8 @@ use core::hash::{Hash, Hasher};
 #[cfg(not(no_global_oom_handling))]
 use core::iter::FromIterator;
 use core::iter::{FusedIterator, Iterator};
+#[cfg(not(bootstrap))]
+use core::marker::Tuple;
 use core::marker::{Destruct, Unpin, Unsize};
 use core::mem;
 use core::ops::{
@@ -1659,7 +1661,7 @@ impl<T, const N: usize> TryFrom<Box<[T]>> for Box<[T; N]> {
 }
 
 #[cfg(not(no_global_oom_handling))]
-#[stable(feature = "boxed_array_try_from_vec", since = "CURRENT_RUSTC_VERSION")]
+#[stable(feature = "boxed_array_try_from_vec", since = "1.66.0")]
 impl<T, const N: usize> TryFrom<Vec<T>> for Box<[T; N]> {
     type Error = Vec<T>;
 
@@ -1979,6 +1981,7 @@ impl<I: ExactSizeIterator + ?Sized, A: Allocator> ExactSizeIterator for Box<I, A
 #[stable(feature = "fused", since = "1.26.0")]
 impl<I: FusedIterator + ?Sized, A: Allocator> FusedIterator for Box<I, A> {}
 
+#[cfg(bootstrap)]
 #[stable(feature = "boxed_closure_impls", since = "1.35.0")]
 impl<Args, F: FnOnce<Args> + ?Sized, A: Allocator> FnOnce<Args> for Box<F, A> {
     type Output = <F as FnOnce<Args>>::Output;
@@ -1988,6 +1991,17 @@ impl<Args, F: FnOnce<Args> + ?Sized, A: Allocator> FnOnce<Args> for Box<F, A> {
     }
 }
 
+#[cfg(not(bootstrap))]
+#[stable(feature = "boxed_closure_impls", since = "1.35.0")]
+impl<Args: Tuple, F: FnOnce<Args> + ?Sized, A: Allocator> FnOnce<Args> for Box<F, A> {
+    type Output = <F as FnOnce<Args>>::Output;
+
+    extern "rust-call" fn call_once(self, args: Args) -> Self::Output {
+        <F as FnOnce<Args>>::call_once(*self, args)
+    }
+}
+
+#[cfg(bootstrap)]
 #[stable(feature = "boxed_closure_impls", since = "1.35.0")]
 impl<Args, F: FnMut<Args> + ?Sized, A: Allocator> FnMut<Args> for Box<F, A> {
     extern "rust-call" fn call_mut(&mut self, args: Args) -> Self::Output {
@@ -1995,6 +2009,15 @@ impl<Args, F: FnMut<Args> + ?Sized, A: Allocator> FnMut<Args> for Box<F, A> {
     }
 }
 
+#[cfg(not(bootstrap))]
+#[stable(feature = "boxed_closure_impls", since = "1.35.0")]
+impl<Args: Tuple, F: FnMut<Args> + ?Sized, A: Allocator> FnMut<Args> for Box<F, A> {
+    extern "rust-call" fn call_mut(&mut self, args: Args) -> Self::Output {
+        <F as FnMut<Args>>::call_mut(self, args)
+    }
+}
+
+#[cfg(bootstrap)]
 #[stable(feature = "boxed_closure_impls", since = "1.35.0")]
 impl<Args, F: Fn<Args> + ?Sized, A: Allocator> Fn<Args> for Box<F, A> {
     extern "rust-call" fn call(&self, args: Args) -> Self::Output {
@@ -2002,6 +2025,14 @@ impl<Args, F: Fn<Args> + ?Sized, A: Allocator> Fn<Args> for Box<F, A> {
     }
 }
 
+#[cfg(not(bootstrap))]
+#[stable(feature = "boxed_closure_impls", since = "1.35.0")]
+impl<Args: Tuple, F: Fn<Args> + ?Sized, A: Allocator> Fn<Args> for Box<F, A> {
+    extern "rust-call" fn call(&self, args: Args) -> Self::Output {
+        <F as Fn<Args>>::call(self, args)
+    }
+}
+
 #[unstable(feature = "coerce_unsized", issue = "27732")]
 impl<T: ?Sized + Unsize<U>, U: ?Sized, A: Allocator> CoerceUnsized<Box<U, A>> for Box<T, A> {}
 
diff --git a/library/alloc/src/collections/btree/map.rs b/library/alloc/src/collections/btree/map.rs
index c4c75e46a2a3..8a7719347123 100644
--- a/library/alloc/src/collections/btree/map.rs
+++ b/library/alloc/src/collections/btree/map.rs
@@ -580,7 +580,7 @@ impl<K, V> BTreeMap<K, V> {
     /// map.insert(1, "a");
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[rustc_const_stable(feature = "const_btree_new", since = "CURRENT_RUSTC_VERSION")]
+    #[rustc_const_stable(feature = "const_btree_new", since = "1.66.0")]
     #[must_use]
     pub const fn new() -> BTreeMap<K, V> {
         BTreeMap { root: None, length: 0, alloc: ManuallyDrop::new(Global), _marker: PhantomData }
@@ -711,7 +711,7 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> {
     /// map.insert(2, "a");
     /// assert_eq!(map.first_key_value(), Some((&1, &"b")));
     /// ```
-    #[stable(feature = "map_first_last", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "map_first_last", since = "1.66.0")]
     pub fn first_key_value(&self) -> Option<(&K, &V)>
     where
         K: Ord,
@@ -739,7 +739,7 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> {
     /// assert_eq!(*map.get(&1).unwrap(), "first");
     /// assert_eq!(*map.get(&2).unwrap(), "b");
     /// ```
-    #[stable(feature = "map_first_last", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "map_first_last", since = "1.66.0")]
     pub fn first_entry(&mut self) -> Option<OccupiedEntry<'_, K, V, A>>
     where
         K: Ord,
@@ -773,7 +773,7 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> {
     /// }
     /// assert!(map.is_empty());
     /// ```
-    #[stable(feature = "map_first_last", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "map_first_last", since = "1.66.0")]
     pub fn pop_first(&mut self) -> Option<(K, V)>
     where
         K: Ord,
@@ -796,7 +796,7 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> {
     /// map.insert(2, "a");
     /// assert_eq!(map.last_key_value(), Some((&2, &"a")));
     /// ```
-    #[stable(feature = "map_first_last", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "map_first_last", since = "1.66.0")]
     pub fn last_key_value(&self) -> Option<(&K, &V)>
     where
         K: Ord,
@@ -824,7 +824,7 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> {
     /// assert_eq!(*map.get(&1).unwrap(), "a");
     /// assert_eq!(*map.get(&2).unwrap(), "last");
     /// ```
-    #[stable(feature = "map_first_last", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "map_first_last", since = "1.66.0")]
     pub fn last_entry(&mut self) -> Option<OccupiedEntry<'_, K, V, A>>
     where
         K: Ord,
@@ -858,7 +858,7 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> {
     /// }
     /// assert!(map.is_empty());
     /// ```
-    #[stable(feature = "map_first_last", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "map_first_last", since = "1.66.0")]
     pub fn pop_last(&mut self) -> Option<(K, V)>
     where
         K: Ord,
diff --git a/library/alloc/src/collections/btree/node/tests.rs b/library/alloc/src/collections/btree/node/tests.rs
index aadb0dc9c40d..64bce0ff8c04 100644
--- a/library/alloc/src/collections/btree/node/tests.rs
+++ b/library/alloc/src/collections/btree/node/tests.rs
@@ -94,6 +94,7 @@ fn test_partial_eq() {
 
 #[test]
 #[cfg(target_arch = "x86_64")]
+#[cfg_attr(miri, ignore)] // We'd like to run Miri with layout randomization
 fn test_sizes() {
     assert_eq!(core::mem::size_of::<LeafNode<(), ()>>(), 16);
     assert_eq!(core::mem::size_of::<LeafNode<i64, i64>>(), 16 + CAPACITY * 2 * 8);
diff --git a/library/alloc/src/collections/btree/set.rs b/library/alloc/src/collections/btree/set.rs
index b8e5cf8eb5a8..4ddb21192520 100644
--- a/library/alloc/src/collections/btree/set.rs
+++ b/library/alloc/src/collections/btree/set.rs
@@ -343,7 +343,7 @@ impl<T> BTreeSet<T> {
     /// let mut set: BTreeSet<i32> = BTreeSet::new();
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[rustc_const_stable(feature = "const_btree_new", since = "CURRENT_RUSTC_VERSION")]
+    #[rustc_const_stable(feature = "const_btree_new", since = "1.66.0")]
     #[must_use]
     pub const fn new() -> BTreeSet<T> {
         BTreeSet { map: BTreeMap::new() }
@@ -796,7 +796,7 @@ impl<T, A: Allocator + Clone> BTreeSet<T, A> {
     /// assert_eq!(set.first(), Some(&1));
     /// ```
     #[must_use]
-    #[stable(feature = "map_first_last", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "map_first_last", since = "1.66.0")]
     pub fn first(&self) -> Option<&T>
     where
         T: Ord,
@@ -822,7 +822,7 @@ impl<T, A: Allocator + Clone> BTreeSet<T, A> {
     /// assert_eq!(set.last(), Some(&2));
     /// ```
     #[must_use]
-    #[stable(feature = "map_first_last", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "map_first_last", since = "1.66.0")]
     pub fn last(&self) -> Option<&T>
     where
         T: Ord,
@@ -846,7 +846,7 @@ impl<T, A: Allocator + Clone> BTreeSet<T, A> {
     /// }
     /// assert!(set.is_empty());
     /// ```
-    #[stable(feature = "map_first_last", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "map_first_last", since = "1.66.0")]
     pub fn pop_first(&mut self) -> Option<T>
     where
         T: Ord,
@@ -870,7 +870,7 @@ impl<T, A: Allocator + Clone> BTreeSet<T, A> {
     /// }
     /// assert!(set.is_empty());
     /// ```
-    #[stable(feature = "map_first_last", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "map_first_last", since = "1.66.0")]
     pub fn pop_last(&mut self) -> Option<T>
     where
         T: Ord,
diff --git a/library/alloc/src/collections/mod.rs b/library/alloc/src/collections/mod.rs
index 161a375736c6..3e0b0f735508 100644
--- a/library/alloc/src/collections/mod.rs
+++ b/library/alloc/src/collections/mod.rs
@@ -139,7 +139,7 @@ impl Display for TryReserveError {
                 " because the computed capacity exceeded the collection's maximum"
             }
             TryReserveErrorKind::AllocError { .. } => {
-                " because the memory allocator returned a error"
+                " because the memory allocator returned an error"
             }
         };
         fmt.write_str(reason)
diff --git a/library/alloc/src/collections/vec_deque/tests.rs b/library/alloc/src/collections/vec_deque/tests.rs
index 1f2daef213c3..6e0f83020f95 100644
--- a/library/alloc/src/collections/vec_deque/tests.rs
+++ b/library/alloc/src/collections/vec_deque/tests.rs
@@ -3,7 +3,6 @@ use core::iter::TrustedLen;
 use super::*;
 
 #[bench]
-#[cfg_attr(miri, ignore)] // isolated Miri does not support benchmarks
 fn bench_push_back_100(b: &mut test::Bencher) {
     let mut deq = VecDeque::with_capacity(101);
     b.iter(|| {
@@ -16,7 +15,6 @@ fn bench_push_back_100(b: &mut test::Bencher) {
 }
 
 #[bench]
-#[cfg_attr(miri, ignore)] // isolated Miri does not support benchmarks
 fn bench_push_front_100(b: &mut test::Bencher) {
     let mut deq = VecDeque::with_capacity(101);
     b.iter(|| {
@@ -29,12 +27,15 @@ fn bench_push_front_100(b: &mut test::Bencher) {
 }
 
 #[bench]
-#[cfg_attr(miri, ignore)] // isolated Miri does not support benchmarks
 fn bench_pop_back_100(b: &mut test::Bencher) {
-    let mut deq = VecDeque::<i32>::with_capacity(101);
+    let size = 100;
+    let mut deq = VecDeque::<i32>::with_capacity(size + 1);
+    // We'll mess with private state to pretend like `deq` is filled.
+    // Make sure the buffer is initialized so that we don't read uninit memory.
+    unsafe { deq.ptr().write_bytes(0u8, size + 1) };
 
     b.iter(|| {
-        deq.head = 100;
+        deq.head = size;
         deq.tail = 0;
         while !deq.is_empty() {
             test::black_box(deq.pop_back());
@@ -43,9 +44,9 @@ fn bench_pop_back_100(b: &mut test::Bencher) {
 }
 
 #[bench]
-#[cfg_attr(miri, ignore)] // isolated Miri does not support benchmarks
 fn bench_retain_whole_10000(b: &mut test::Bencher) {
-    let v = (1..100000).collect::<VecDeque<u32>>();
+    let size = if cfg!(miri) { 1000 } else { 100000 };
+    let v = (1..size).collect::<VecDeque<u32>>();
 
     b.iter(|| {
         let mut v = v.clone();
@@ -54,9 +55,9 @@ fn bench_retain_whole_10000(b: &mut test::Bencher) {
 }
 
 #[bench]
-#[cfg_attr(miri, ignore)] // isolated Miri does not support benchmarks
 fn bench_retain_odd_10000(b: &mut test::Bencher) {
-    let v = (1..100000).collect::<VecDeque<u32>>();
+    let size = if cfg!(miri) { 1000 } else { 100000 };
+    let v = (1..size).collect::<VecDeque<u32>>();
 
     b.iter(|| {
         let mut v = v.clone();
@@ -65,23 +66,26 @@ fn bench_retain_odd_10000(b: &mut test::Bencher) {
 }
 
 #[bench]
-#[cfg_attr(miri, ignore)] // isolated Miri does not support benchmarks
 fn bench_retain_half_10000(b: &mut test::Bencher) {
-    let v = (1..100000).collect::<VecDeque<u32>>();
+    let size = if cfg!(miri) { 1000 } else { 100000 };
+    let v = (1..size).collect::<VecDeque<u32>>();
 
     b.iter(|| {
         let mut v = v.clone();
-        v.retain(|x| *x > 50000)
+        v.retain(|x| *x > size / 2)
     })
 }
 
 #[bench]
-#[cfg_attr(miri, ignore)] // isolated Miri does not support benchmarks
 fn bench_pop_front_100(b: &mut test::Bencher) {
-    let mut deq = VecDeque::<i32>::with_capacity(101);
+    let size = 100;
+    let mut deq = VecDeque::<i32>::with_capacity(size + 1);
+    // We'll mess with private state to pretend like `deq` is filled.
+    // Make sure the buffer is initialized so that we don't read uninit memory.
+    unsafe { deq.ptr().write_bytes(0u8, size + 1) };
 
     b.iter(|| {
-        deq.head = 100;
+        deq.head = size;
         deq.tail = 0;
         while !deq.is_empty() {
             test::black_box(deq.pop_front());
diff --git a/library/alloc/src/lib.rs b/library/alloc/src/lib.rs
index ce36b116f139..008926666c13 100644
--- a/library/alloc/src/lib.rs
+++ b/library/alloc/src/lib.rs
@@ -150,6 +150,7 @@
 #![feature(trusted_len)]
 #![feature(trusted_random_access)]
 #![feature(try_trait_v2)]
+#![cfg_attr(not(bootstrap), feature(tuple_trait))]
 #![feature(unchecked_math)]
 #![feature(unicode_internals)]
 #![feature(unsize)]
diff --git a/library/alloc/src/rc.rs b/library/alloc/src/rc.rs
index 9c229665c7e9..006d813e5f9f 100644
--- a/library/alloc/src/rc.rs
+++ b/library/alloc/src/rc.rs
@@ -1110,8 +1110,8 @@ impl<T: ?Sized> Rc<T> {
 
     #[inline]
     #[stable(feature = "ptr_eq", since = "1.17.0")]
-    /// Returns `true` if the two `Rc`s point to the same allocation
-    /// (in a vein similar to [`ptr::eq`]).
+    /// Returns `true` if the two `Rc`s point to the same allocation in a vein similar to
+    /// [`ptr::eq`]. See [that function][`ptr::eq`] for caveats when comparing `dyn Trait` pointers.
     ///
     /// # Examples
     ///
@@ -2419,9 +2419,9 @@ impl<T: ?Sized> Weak<T> {
         }
     }
 
-    /// Returns `true` if the two `Weak`s point to the same allocation (similar to
-    /// [`ptr::eq`]), or if both don't point to any allocation
-    /// (because they were created with `Weak::new()`).
+    /// Returns `true` if the two `Weak`s point to the same allocation similar to [`ptr::eq`], or if
+    /// both don't point to any allocation (because they were created with `Weak::new()`). See [that
+    /// function][`ptr::eq`] for caveats when comparing `dyn Trait` pointers.
     ///
     /// # Notes
     ///
diff --git a/library/alloc/src/string.rs b/library/alloc/src/string.rs
index c436adf70067..c9ba8921f6ec 100644
--- a/library/alloc/src/string.rs
+++ b/library/alloc/src/string.rs
@@ -949,7 +949,7 @@ impl String {
     /// assert_eq!(string, "abcdecdeabecde");
     /// ```
     #[cfg(not(no_global_oom_handling))]
-    #[unstable(feature = "string_extend_from_within", issue = "none")]
+    #[unstable(feature = "string_extend_from_within", issue = "103806")]
     pub fn extend_from_within<R>(&mut self, src: R)
     where
         R: RangeBounds<usize>,
diff --git a/library/alloc/src/sync.rs b/library/alloc/src/sync.rs
index e8d9de4fb3ce..81cd77074885 100644
--- a/library/alloc/src/sync.rs
+++ b/library/alloc/src/sync.rs
@@ -1117,8 +1117,8 @@ impl<T: ?Sized> Arc<T> {
         drop(Weak { ptr: self.ptr });
     }
 
-    /// Returns `true` if the two `Arc`s point to the same allocation
-    /// (in a vein similar to [`ptr::eq`]).
+    /// Returns `true` if the two `Arc`s point to the same allocation in a vein similar to
+    /// [`ptr::eq`]. See [that function][`ptr::eq`] for caveats when comparing `dyn Trait` pointers.
     ///
     /// # Examples
     ///
@@ -2069,9 +2069,9 @@ impl<T: ?Sized> Weak<T> {
         }
     }
 
-    /// Returns `true` if the two `Weak`s point to the same allocation (similar to
-    /// [`ptr::eq`]), or if both don't point to any allocation
-    /// (because they were created with `Weak::new()`).
+    /// Returns `true` if the two `Weak`s point to the same allocation similar to [`ptr::eq`], or if
+    /// both don't point to any allocation (because they were created with `Weak::new()`). See [that
+    /// function][`ptr::eq`] for caveats when comparing `dyn Trait` pointers.
     ///
     /// # Notes
     ///
diff --git a/library/alloc/src/vec/mod.rs b/library/alloc/src/vec/mod.rs
index 6a71f08330ca..766006939fa4 100644
--- a/library/alloc/src/vec/mod.rs
+++ b/library/alloc/src/vec/mod.rs
@@ -868,13 +868,14 @@ impl<T, A: Allocator> Vec<T, A> {
         (ptr, len, capacity, alloc)
     }
 
-    /// Returns the number of elements the vector can hold without
+    /// Returns the total number of elements the vector can hold without
     /// reallocating.
     ///
     /// # Examples
     ///
     /// ```
-    /// let vec: Vec<i32> = Vec::with_capacity(10);
+    /// let mut vec: Vec<i32> = Vec::with_capacity(10);
+    /// vec.push(42);
     /// assert_eq!(vec.capacity(), 10);
     /// ```
     #[inline]
@@ -2587,7 +2588,7 @@ impl<T: Clone, A: Allocator> ExtendFromWithinSpec for Vec<T, A> {
         let (this, spare, len) = unsafe { self.split_at_spare_mut_with_len() };
 
         // SAFETY:
-        // - caller guaratees that src is a valid index
+        // - caller guarantees that src is a valid index
         let to_clone = unsafe { this.get_unchecked(src) };
 
         iter::zip(to_clone, spare)
@@ -2606,7 +2607,7 @@ impl<T: Copy, A: Allocator> ExtendFromWithinSpec for Vec<T, A> {
             let (init, spare) = self.split_at_spare_mut();
 
             // SAFETY:
-            // - caller guaratees that `src` is a valid index
+            // - caller guarantees that `src` is a valid index
             let source = unsafe { init.get_unchecked(src) };
 
             // SAFETY:
@@ -2779,7 +2780,7 @@ impl<T, A: Allocator> IntoIterator for Vec<T, A> {
     /// assert_eq!(v_iter.next(), None);
     /// ```
     #[inline]
-    fn into_iter(self) -> IntoIter<T, A> {
+    fn into_iter(self) -> Self::IntoIter {
         unsafe {
             let mut me = ManuallyDrop::new(self);
             let alloc = ManuallyDrop::new(ptr::read(me.allocator()));
@@ -2807,7 +2808,7 @@ impl<'a, T, A: Allocator> IntoIterator for &'a Vec<T, A> {
     type Item = &'a T;
     type IntoIter = slice::Iter<'a, T>;
 
-    fn into_iter(self) -> slice::Iter<'a, T> {
+    fn into_iter(self) -> Self::IntoIter {
         self.iter()
     }
 }
@@ -2817,7 +2818,7 @@ impl<'a, T, A: Allocator> IntoIterator for &'a mut Vec<T, A> {
     type Item = &'a mut T;
     type IntoIter = slice::IterMut<'a, T>;
 
-    fn into_iter(self) -> slice::IterMut<'a, T> {
+    fn into_iter(self) -> Self::IntoIter {
         self.iter_mut()
     }
 }
diff --git a/library/core/benches/iter.rs b/library/core/benches/iter.rs
index 38887f29af15..9193c79bee87 100644
--- a/library/core/benches/iter.rs
+++ b/library/core/benches/iter.rs
@@ -1,3 +1,4 @@
+use core::borrow::Borrow;
 use core::iter::*;
 use core::mem;
 use core::num::Wrapping;
@@ -403,13 +404,31 @@ fn bench_trusted_random_access_adapters(b: &mut Bencher) {
 
 /// Exercises the iter::Copied specialization for slice::Iter
 #[bench]
-fn bench_copied_array_chunks(b: &mut Bencher) {
+fn bench_copied_chunks(b: &mut Bencher) {
+    let v = vec![1u8; 1024];
+
+    b.iter(|| {
+        let mut iter = black_box(&v).iter().copied();
+        let mut acc = Wrapping(0);
+        // This uses a while-let loop to side-step the TRA specialization in ArrayChunks
+        while let Ok(chunk) = iter.next_chunk::<{ mem::size_of::<u64>() }>() {
+            let d = u64::from_ne_bytes(chunk);
+            acc += Wrapping(d.rotate_left(7).wrapping_add(1));
+        }
+        acc
+    })
+}
+
+/// Exercises the TrustedRandomAccess specialization in ArrayChunks
+#[bench]
+fn bench_trusted_random_access_chunks(b: &mut Bencher) {
     let v = vec![1u8; 1024];
 
     b.iter(|| {
         black_box(&v)
             .iter()
-            .copied()
+            // this shows that we're not relying on the slice::Iter specialization in Copied
+            .map(|b| *b.borrow())
             .array_chunks::<{ mem::size_of::<u64>() }>()
             .map(|ary| {
                 let d = u64::from_ne_bytes(ary);
diff --git a/library/core/benches/lib.rs b/library/core/benches/lib.rs
index 1e462e3fc3f8..f1244d93285e 100644
--- a/library/core/benches/lib.rs
+++ b/library/core/benches/lib.rs
@@ -1,10 +1,10 @@
 // wasm32 does not support benches (no time).
 #![cfg(not(target_arch = "wasm32"))]
 #![feature(flt2dec)]
-#![feature(int_log)]
 #![feature(test)]
 #![feature(trusted_random_access)]
 #![feature(iter_array_chunks)]
+#![feature(iter_next_chunk)]
 
 extern crate test;
 
diff --git a/library/core/src/alloc/layout.rs b/library/core/src/alloc/layout.rs
index 920e559cc4aa..f50d9a8e1bdf 100644
--- a/library/core/src/alloc/layout.rs
+++ b/library/core/src/alloc/layout.rs
@@ -7,8 +7,8 @@
 use crate::cmp;
 use crate::error::Error;
 use crate::fmt;
-use crate::mem::{self, ValidAlign};
-use crate::ptr::NonNull;
+use crate::mem;
+use crate::ptr::{Alignment, NonNull};
 
 // While this function is used in one place and its implementation
 // could be inlined, the previous attempts to do so made rustc
@@ -46,7 +46,7 @@ pub struct Layout {
     //
     // (However, we do not analogously require `align >= sizeof(void*)`,
     //  even though that is *also* a requirement of `posix_memalign`.)
-    align: ValidAlign,
+    align: Alignment,
 }
 
 impl Layout {
@@ -71,11 +71,11 @@ impl Layout {
         }
 
         // SAFETY: just checked that align is a power of two.
-        Layout::from_size_valid_align(size, unsafe { ValidAlign::new_unchecked(align) })
+        Layout::from_size_alignment(size, unsafe { Alignment::new_unchecked(align) })
     }
 
     #[inline(always)]
-    const fn max_size_for_align(align: ValidAlign) -> usize {
+    const fn max_size_for_align(align: Alignment) -> usize {
         // (power-of-two implies align != 0.)
 
         // Rounded up size is:
@@ -95,7 +95,7 @@ impl Layout {
 
     /// Internal helper constructor to skip revalidating alignment validity.
     #[inline]
-    const fn from_size_valid_align(size: usize, align: ValidAlign) -> Result<Self, LayoutError> {
+    const fn from_size_alignment(size: usize, align: Alignment) -> Result<Self, LayoutError> {
         if size > Self::max_size_for_align(align) {
             return Err(LayoutError);
         }
@@ -117,7 +117,7 @@ impl Layout {
     #[rustc_allow_const_fn_unstable(ptr_alignment_type)]
     pub const unsafe fn from_size_align_unchecked(size: usize, align: usize) -> Self {
         // SAFETY: the caller is required to uphold the preconditions.
-        unsafe { Layout { size, align: ValidAlign::new_unchecked(align) } }
+        unsafe { Layout { size, align: Alignment::new_unchecked(align) } }
     }
 
     /// The minimum size in bytes for a memory block of this layout.
@@ -321,7 +321,7 @@ impl Layout {
         let alloc_size = padded_size.checked_mul(n).ok_or(LayoutError)?;
 
         // The safe constructor is called here to enforce the isize size limit.
-        Layout::from_size_valid_align(alloc_size, self.align).map(|layout| (layout, padded_size))
+        Layout::from_size_alignment(alloc_size, self.align).map(|layout| (layout, padded_size))
     }
 
     /// Creates a layout describing the record for `self` followed by
@@ -379,7 +379,7 @@ impl Layout {
         let new_size = offset.checked_add(next.size()).ok_or(LayoutError)?;
 
         // The safe constructor is called here to enforce the isize size limit.
-        let layout = Layout::from_size_valid_align(new_size, new_align)?;
+        let layout = Layout::from_size_alignment(new_size, new_align)?;
         Ok((layout, offset))
     }
 
@@ -400,7 +400,7 @@ impl Layout {
     pub fn repeat_packed(&self, n: usize) -> Result<Self, LayoutError> {
         let size = self.size().checked_mul(n).ok_or(LayoutError)?;
         // The safe constructor is called here to enforce the isize size limit.
-        Layout::from_size_valid_align(size, self.align)
+        Layout::from_size_alignment(size, self.align)
     }
 
     /// Creates a layout describing the record for `self` followed by
@@ -414,7 +414,7 @@ impl Layout {
     pub fn extend_packed(&self, next: Self) -> Result<Self, LayoutError> {
         let new_size = self.size().checked_add(next.size()).ok_or(LayoutError)?;
         // The safe constructor is called here to enforce the isize size limit.
-        Layout::from_size_valid_align(new_size, self.align)
+        Layout::from_size_alignment(new_size, self.align)
     }
 
     /// Creates a layout describing the record for a `[T; n]`.
@@ -425,10 +425,10 @@ impl Layout {
     #[inline]
     pub fn array<T>(n: usize) -> Result<Self, LayoutError> {
         // Reduce the amount of code we need to monomorphize per `T`.
-        return inner(mem::size_of::<T>(), ValidAlign::of::<T>(), n);
+        return inner(mem::size_of::<T>(), Alignment::of::<T>(), n);
 
         #[inline]
-        fn inner(element_size: usize, align: ValidAlign, n: usize) -> Result<Layout, LayoutError> {
+        fn inner(element_size: usize, align: Alignment, n: usize) -> Result<Layout, LayoutError> {
             // We need to check two things about the size:
             //  - That the total size won't overflow a `usize`, and
             //  - That the total size still fits in an `isize`.
@@ -443,7 +443,7 @@ impl Layout {
 
             // SAFETY: We just checked above that the `array_size` will not
             // exceed `isize::MAX` even when rounded up to the alignment.
-            // And `ValidAlign` guarantees it's a power of two.
+            // And `Alignment` guarantees it's a power of two.
             unsafe { Ok(Layout::from_size_align_unchecked(array_size, align.as_usize())) }
         }
     }
diff --git a/library/core/src/array/mod.rs b/library/core/src/array/mod.rs
index eae0e1c76186..2090756d7a3e 100644
--- a/library/core/src/array/mod.rs
+++ b/library/core/src/array/mod.rs
@@ -865,24 +865,6 @@ where
         return Ok(Try::from_output(unsafe { mem::zeroed() }));
     }
 
-    struct Guard<'a, T, const N: usize> {
-        array_mut: &'a mut [MaybeUninit<T>; N],
-        initialized: usize,
-    }
-
-    impl<T, const N: usize> Drop for Guard<'_, T, N> {
-        fn drop(&mut self) {
-            debug_assert!(self.initialized <= N);
-
-            // SAFETY: this slice will contain only initialized objects.
-            unsafe {
-                crate::ptr::drop_in_place(MaybeUninit::slice_assume_init_mut(
-                    &mut self.array_mut.get_unchecked_mut(..self.initialized),
-                ));
-            }
-        }
-    }
-
     let mut array = MaybeUninit::uninit_array::<N>();
     let mut guard = Guard { array_mut: &mut array, initialized: 0 };
 
@@ -896,13 +878,11 @@ where
                     ControlFlow::Continue(elem) => elem,
                 };
 
-                // SAFETY: `guard.initialized` starts at 0, is increased by one in the
-                // loop and the loop is aborted once it reaches N (which is
-                // `array.len()`).
+                // SAFETY: `guard.initialized` starts at 0, which means push can be called
+                // at most N times, which this loop does.
                 unsafe {
-                    guard.array_mut.get_unchecked_mut(guard.initialized).write(item);
+                    guard.push_unchecked(item);
                 }
-                guard.initialized += 1;
             }
             None => {
                 let alive = 0..guard.initialized;
@@ -920,6 +900,55 @@ where
     Ok(Try::from_output(output))
 }
 
+/// Panic guard for incremental initialization of arrays.
+///
+/// Disarm the guard with `mem::forget` once the array has been initialized.
+///
+/// # Safety
+///
+/// All write accesses to this structure are unsafe and must maintain a correct
+/// count of `initialized` elements.
+///
+/// To minimize indirection fields are still pub but callers should at least use
+/// `push_unchecked` to signal that something unsafe is going on.
+pub(crate) struct Guard<'a, T, const N: usize> {
+    /// The array to be initialized.
+    pub array_mut: &'a mut [MaybeUninit<T>; N],
+    /// The number of items that have been initialized so far.
+    pub initialized: usize,
+}
+
+impl<T, const N: usize> Guard<'_, T, N> {
+    /// Adds an item to the array and updates the initialized item counter.
+    ///
+    /// # Safety
+    ///
+    /// No more than N elements must be initialized.
+    #[inline]
+    pub unsafe fn push_unchecked(&mut self, item: T) {
+        // SAFETY: If `initialized` was correct before and the caller does not
+        // invoke this method more than N times then writes will be in-bounds
+        // and slots will not be initialized more than once.
+        unsafe {
+            self.array_mut.get_unchecked_mut(self.initialized).write(item);
+            self.initialized = self.initialized.unchecked_add(1);
+        }
+    }
+}
+
+impl<T, const N: usize> Drop for Guard<'_, T, N> {
+    fn drop(&mut self) {
+        debug_assert!(self.initialized <= N);
+
+        // SAFETY: this slice will contain only initialized objects.
+        unsafe {
+            crate::ptr::drop_in_place(MaybeUninit::slice_assume_init_mut(
+                &mut self.array_mut.get_unchecked_mut(..self.initialized),
+            ));
+        }
+    }
+}
+
 /// Returns the next chunk of `N` items from the iterator or errors with an
 /// iterator over the remainder. Used for `Iterator::next_chunk`.
 #[inline]
diff --git a/library/core/src/async_iter/async_iter.rs b/library/core/src/async_iter/async_iter.rs
index 016a3685e850..12a47f9fc762 100644
--- a/library/core/src/async_iter/async_iter.rs
+++ b/library/core/src/async_iter/async_iter.rs
@@ -2,7 +2,7 @@ use crate::ops::DerefMut;
 use crate::pin::Pin;
 use crate::task::{Context, Poll};
 
-/// An interface for dealing with asynchronous iterators.
+/// A trait for dealing with asynchronous iterators.
 ///
 /// This is the main async iterator trait. For more about the concept of async iterators
 /// generally, please see the [module-level documentation]. In particular, you
diff --git a/library/core/src/cell.rs b/library/core/src/cell.rs
index 3451a25504e3..f2975d054572 100644
--- a/library/core/src/cell.rs
+++ b/library/core/src/cell.rs
@@ -1816,6 +1816,8 @@ impl<T: ?Sized + fmt::Display> fmt::Display for RefMut<'_, T> {
 ///
 /// [`.get_mut()`]: `UnsafeCell::get_mut`
 ///
+/// # Memory layout
+///
 /// `UnsafeCell<T>` has the same in-memory representation as its inner type `T`. A consequence
 /// of this guarantee is that it is possible to convert between `T` and `UnsafeCell<T>`.
 /// Special care has to be taken when converting a nested `T` inside of an `Outer<T>` type
@@ -1825,35 +1827,44 @@ impl<T: ?Sized + fmt::Display> fmt::Display for RefMut<'_, T> {
 /// Therefore this is not a valid conversion, despite `NonNull<u8>` and `UnsafeCell<NonNull<u8>>>`
 /// having the same memory layout. This is because `UnsafeCell` disables niche optimizations in
 /// order to avoid its interior mutability property from spreading from `T` into the `Outer` type,
-/// thus this can cause distortions in the type size in these cases. Furthermore, it is only valid
-/// to obtain a `*mut T` pointer to the contents of a _shared_ `UnsafeCell<T>` through [`.get()`]
-/// or [`.raw_get()`]. A `&mut T` reference can be obtained by either dereferencing this pointer or
-/// by calling [`.get_mut()`] on an _exclusive_ `UnsafeCell<T>`, e.g.:
+/// thus this can cause distortions in the type size in these cases.
+///
+/// Note that the only valid way to obtain a `*mut T` pointer to the contents of a
+/// _shared_ `UnsafeCell<T>` is through [`.get()`]  or [`.raw_get()`]. A `&mut T` reference
+/// can be obtained by either dereferencing this pointer or by calling [`.get_mut()`]
+/// on an _exclusive_ `UnsafeCell<T>`. Even though `T` and `UnsafeCell<T>` have the
+/// same memory layout, the following is not allowed and undefined behavior:
+///
+/// ```rust,no_run
+/// # use std::cell::UnsafeCell;
+/// unsafe fn not_allowed<T>(ptr: &UnsafeCell<T>) -> &mut T {
+///   let t = ptr as *const UnsafeCell<T> as *mut T;
+///   // This is undefined behavior, because the `*mut T` pointer
+///   // was not obtained through `.get()` nor `.raw_get()`:
+///   unsafe { &mut *t }
+/// }
+/// ```
+///
+/// Instead, do this:
 ///
 /// ```rust
-/// use std::cell::UnsafeCell;
+/// # use std::cell::UnsafeCell;
+/// // Safety: the caller must ensure that there are no references that
+/// // point to the *contents* of the `UnsafeCell`.
+/// unsafe fn get_mut<T>(ptr: &UnsafeCell<T>) -> &mut T {
+///   unsafe { &mut *ptr.get() }
+/// }
+/// ```
 ///
-/// let mut x: UnsafeCell<u32> = UnsafeCell::new(5);
-/// let shared: &UnsafeCell<u32> = &x;
-/// // using `.get()` is okay:
-/// unsafe {
-///     // SAFETY: there exist no other references to the contents of `x`
-///     let exclusive: &mut u32 = &mut *shared.get();
-/// };
-/// // using `.raw_get()` is also okay:
-/// unsafe {
-///     // SAFETY: there exist no other references to the contents of `x` in this scope
-///     let exclusive: &mut u32 = &mut *UnsafeCell::raw_get(shared as *const _);
-/// };
-/// // using `.get_mut()` is always safe:
-/// let exclusive: &mut u32 = x.get_mut();
+/// Converting in the other direction from a `&mut T`
+/// to an `&UnsafeCell<T>` is allowed:
 ///
-/// // when we have exclusive access, we can convert it to a shared `&UnsafeCell`:
-/// unsafe {
-///     // SAFETY: `u32` has no niche, therefore it has the same layout as `UnsafeCell<u32>`
-///     let shared: &UnsafeCell<u32> = &*(exclusive as *mut _ as *const UnsafeCell<u32>);
-///     // SAFETY: there exist no other *active* references to the contents of `x` in this scope
-///     let exclusive: &mut u32 = &mut *shared.get();
+/// ```rust
+/// # use std::cell::UnsafeCell;
+/// fn get_shared<T>(ptr: &mut T) -> &UnsafeCell<T> {
+///   let t = ptr as *mut T as *const UnsafeCell<T>;
+///   // SAFETY: `T` and `UnsafeCell<T>` have the same memory layout
+///   unsafe { &*t }
 /// }
 /// ```
 ///
@@ -1925,7 +1936,7 @@ impl<T> UnsafeCell<T> {
     /// Constructs a new instance of `UnsafeCell` which will wrap the specified
     /// value.
     ///
-    /// All access to the inner value through methods is `unsafe`.
+    /// All access to the inner value through `&UnsafeCell<T>` requires `unsafe` code.
     ///
     /// # Examples
     ///
diff --git a/library/core/src/char/convert.rs b/library/core/src/char/convert.rs
index 7c5f82f5ea49..f1a51a550f57 100644
--- a/library/core/src/char/convert.rs
+++ b/library/core/src/char/convert.rs
@@ -18,7 +18,6 @@ pub(super) const fn from_u32(i: u32) -> Option<char> {
 }
 
 /// Converts a `u32` to a `char`, ignoring validity. See [`char::from_u32_unchecked`].
-#[rustc_const_unstable(feature = "const_char_convert", issue = "89259")]
 #[inline]
 #[must_use]
 pub(super) const unsafe fn from_u32_unchecked(i: u32) -> char {
diff --git a/library/core/src/char/methods.rs b/library/core/src/char/methods.rs
index bb83599369c1..c05b68e30bc9 100644
--- a/library/core/src/char/methods.rs
+++ b/library/core/src/char/methods.rs
@@ -140,7 +140,7 @@ impl char {
     /// assert_eq!(None, c);
     /// ```
     #[stable(feature = "assoc_char_funcs", since = "1.52.0")]
-    #[rustc_const_unstable(feature = "const_char_convert", issue = "89259")]
+    #[rustc_const_stable(feature = "const_char_convert", since = "CURRENT_RUSTC_VERSION")]
     #[must_use]
     #[inline]
     pub const fn from_u32(i: u32) -> Option<char> {
@@ -183,7 +183,7 @@ impl char {
     /// assert_eq!('❤', c);
     /// ```
     #[stable(feature = "assoc_char_funcs", since = "1.52.0")]
-    #[rustc_const_unstable(feature = "const_char_convert", issue = "89259")]
+    #[rustc_const_unstable(feature = "const_char_from_u32_unchecked", issue = "89259")]
     #[must_use]
     #[inline]
     pub const unsafe fn from_u32_unchecked(i: u32) -> char {
@@ -241,7 +241,7 @@ impl char {
     /// let _c = char::from_digit(1, 37);
     /// ```
     #[stable(feature = "assoc_char_funcs", since = "1.52.0")]
-    #[rustc_const_unstable(feature = "const_char_convert", issue = "89259")]
+    #[rustc_const_stable(feature = "const_char_convert", since = "CURRENT_RUSTC_VERSION")]
     #[must_use]
     #[inline]
     pub const fn from_digit(num: u32, radix: u32) -> Option<char> {
@@ -338,7 +338,7 @@ impl char {
     /// let _ = '1'.to_digit(37);
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[rustc_const_unstable(feature = "const_char_convert", issue = "89259")]
+    #[rustc_const_stable(feature = "const_char_convert", since = "CURRENT_RUSTC_VERSION")]
     #[must_use = "this returns the result of the operation, \
                   without modifying the original"]
     #[inline]
diff --git a/library/core/src/char/mod.rs b/library/core/src/char/mod.rs
index b34a7121631c..55552376280a 100644
--- a/library/core/src/char/mod.rs
+++ b/library/core/src/char/mod.rs
@@ -110,7 +110,7 @@ pub fn decode_utf16<I: IntoIterator<Item = u16>>(iter: I) -> DecodeUtf16<I::Into
 
 /// Converts a `u32` to a `char`. Use [`char::from_u32`] instead.
 #[stable(feature = "rust1", since = "1.0.0")]
-#[rustc_const_unstable(feature = "const_char_convert", issue = "89259")]
+#[rustc_const_stable(feature = "const_char_convert", since = "CURRENT_RUSTC_VERSION")]
 #[must_use]
 #[inline]
 pub const fn from_u32(i: u32) -> Option<char> {
@@ -120,7 +120,7 @@ pub const fn from_u32(i: u32) -> Option<char> {
 /// Converts a `u32` to a `char`, ignoring validity. Use [`char::from_u32_unchecked`].
 /// instead.
 #[stable(feature = "char_from_unchecked", since = "1.5.0")]
-#[rustc_const_unstable(feature = "const_char_convert", issue = "89259")]
+#[rustc_const_unstable(feature = "const_char_from_u32_unchecked", issue = "89259")]
 #[must_use]
 #[inline]
 pub const unsafe fn from_u32_unchecked(i: u32) -> char {
@@ -130,7 +130,7 @@ pub const unsafe fn from_u32_unchecked(i: u32) -> char {
 
 /// Converts a digit in the given radix to a `char`. Use [`char::from_digit`] instead.
 #[stable(feature = "rust1", since = "1.0.0")]
-#[rustc_const_unstable(feature = "const_char_convert", issue = "89259")]
+#[rustc_const_stable(feature = "const_char_convert", since = "CURRENT_RUSTC_VERSION")]
 #[must_use]
 #[inline]
 pub const fn from_digit(num: u32, radix: u32) -> Option<char> {
diff --git a/library/core/src/cmp.rs b/library/core/src/cmp.rs
index f0fa2e1d2c19..5db5cbfc3dfd 100644
--- a/library/core/src/cmp.rs
+++ b/library/core/src/cmp.rs
@@ -24,6 +24,7 @@
 
 use crate::const_closure::ConstFnMutClosure;
 use crate::marker::Destruct;
+#[cfg(bootstrap)]
 use crate::marker::StructuralPartialEq;
 
 use self::Ordering::*;
@@ -331,6 +332,7 @@ pub struct AssertParamIsEq<T: Eq + ?Sized> {
 /// assert_eq!(Ordering::Greater, result);
 /// ```
 #[derive(Clone, Copy, Eq, Debug, Hash)]
+#[cfg_attr(not(bootstrap), derive_const(PartialOrd, Ord, PartialEq))]
 #[stable(feature = "rust1", since = "1.0.0")]
 #[repr(i8)]
 pub enum Ordering {
@@ -877,10 +879,12 @@ pub macro Ord($item:item) {
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
+#[cfg(bootstrap)]
 impl StructuralPartialEq for Ordering {}
 
 #[stable(feature = "rust1", since = "1.0.0")]
 #[rustc_const_unstable(feature = "const_cmp", issue = "92391")]
+#[cfg(bootstrap)]
 impl const PartialEq for Ordering {
     #[inline]
     fn eq(&self, other: &Self) -> bool {
@@ -890,6 +894,7 @@ impl const PartialEq for Ordering {
 
 #[stable(feature = "rust1", since = "1.0.0")]
 #[rustc_const_unstable(feature = "const_cmp", issue = "92391")]
+#[cfg(bootstrap)]
 impl const Ord for Ordering {
     #[inline]
     fn cmp(&self, other: &Ordering) -> Ordering {
@@ -899,6 +904,7 @@ impl const Ord for Ordering {
 
 #[stable(feature = "rust1", since = "1.0.0")]
 #[rustc_const_unstable(feature = "const_cmp", issue = "92391")]
+#[cfg(bootstrap)]
 impl const PartialOrd for Ordering {
     #[inline]
     fn partial_cmp(&self, other: &Ordering) -> Option<Ordering> {
diff --git a/library/core/src/const_closure.rs b/library/core/src/const_closure.rs
index 9e9c02093be2..151c8e6d8986 100644
--- a/library/core/src/const_closure.rs
+++ b/library/core/src/const_closure.rs
@@ -1,4 +1,6 @@
 use crate::marker::Destruct;
+#[cfg(not(bootstrap))]
+use crate::marker::Tuple;
 
 /// Struct representing a closure with mutably borrowed data.
 ///
@@ -44,6 +46,7 @@ impl<'a, CapturedData: ?Sized, Function> ConstFnMutClosure<&'a mut CapturedData,
 
 macro_rules! impl_fn_mut_tuple {
     ($($var:ident)*) => {
+        #[cfg(bootstrap)]
         #[allow(unused_parens)]
         impl<'a, $($var,)* ClosureArguments, Function, ClosureReturnValue> const
             FnOnce<ClosureArguments> for ConstFnMutClosure<($(&'a mut $var),*), Function>
@@ -56,6 +59,7 @@ macro_rules! impl_fn_mut_tuple {
             self.call_mut(args)
             }
         }
+        #[cfg(bootstrap)]
         #[allow(unused_parens)]
         impl<'a, $($var,)* ClosureArguments, Function, ClosureReturnValue> const
             FnMut<ClosureArguments> for ConstFnMutClosure<($(&'a mut $var),*), Function>
@@ -68,6 +72,32 @@ macro_rules! impl_fn_mut_tuple {
                 (self.func)(($($var),*), args)
             }
         }
+        #[cfg(not(bootstrap))]
+        #[allow(unused_parens)]
+        impl<'a, $($var,)* ClosureArguments: Tuple, Function, ClosureReturnValue> const
+            FnOnce<ClosureArguments> for ConstFnMutClosure<($(&'a mut $var),*), Function>
+        where
+            Function: ~const Fn(($(&mut $var),*), ClosureArguments) -> ClosureReturnValue+ ~const Destruct,
+        {
+            type Output = ClosureReturnValue;
+
+            extern "rust-call" fn call_once(mut self, args: ClosureArguments) -> Self::Output {
+            self.call_mut(args)
+            }
+        }
+        #[cfg(not(bootstrap))]
+        #[allow(unused_parens)]
+        impl<'a, $($var,)* ClosureArguments: Tuple, Function, ClosureReturnValue> const
+            FnMut<ClosureArguments> for ConstFnMutClosure<($(&'a mut $var),*), Function>
+        where
+            Function: ~const Fn(($(&mut $var),*), ClosureArguments)-> ClosureReturnValue,
+        {
+            extern "rust-call" fn call_mut(&mut self, args: ClosureArguments) -> Self::Output {
+                #[allow(non_snake_case)]
+                let ($($var),*) = &mut self.data;
+                (self.func)(($($var),*), args)
+            }
+        }
     };
 }
 impl_fn_mut_tuple!(A);
diff --git a/library/core/src/default.rs b/library/core/src/default.rs
index a5b4e965552c..d96b53de0a33 100644
--- a/library/core/src/default.rs
+++ b/library/core/src/default.rs
@@ -99,7 +99,7 @@
 /// ```
 #[cfg_attr(not(test), rustc_diagnostic_item = "Default")]
 #[stable(feature = "rust1", since = "1.0.0")]
-#[cfg_attr(not(bootstrap), const_trait)]
+#[const_trait]
 pub trait Default: Sized {
     /// Returns the "default value" for a type.
     ///
diff --git a/library/core/src/error.md b/library/core/src/error.md
index 891abebbfd39..78808d489b25 100644
--- a/library/core/src/error.md
+++ b/library/core/src/error.md
@@ -46,7 +46,7 @@ These functions are equivalent, they either return the inner value if the
 `Result` is `Ok` or panic if the `Result` is `Err` printing the inner error
 as the source. The only difference between them is that with `expect` you
 provide a panic error message to be printed alongside the source, whereas
-`unwrap` has a default message indicating only that you unwraped an `Err`.
+`unwrap` has a default message indicating only that you unwrapped an `Err`.
 
 Of the two, `expect` is generally preferred since its `msg` field allows you
 to convey your intent and assumptions which makes tracking down the source
diff --git a/library/core/src/error.rs b/library/core/src/error.rs
index 89053060fbbe..c9c7cdf4defc 100644
--- a/library/core/src/error.rs
+++ b/library/core/src/error.rs
@@ -1,5 +1,5 @@
 #![doc = include_str!("error.md")]
-#![unstable(feature = "error_in_core", issue = "none")]
+#![unstable(feature = "error_in_core", issue = "103765")]
 
 #[cfg(test)]
 mod tests;
@@ -493,7 +493,7 @@ impl Error for crate::char::ParseCharError {
     }
 }
 
-#[stable(feature = "duration_checked_float", since = "CURRENT_RUSTC_VERSION")]
+#[stable(feature = "duration_checked_float", since = "1.66.0")]
 impl Error for crate::time::TryFromFloatSecsError {}
 
 #[stable(feature = "frombyteswithnulerror_impls", since = "1.17.0")]
diff --git a/library/core/src/ffi/c_str.rs b/library/core/src/ffi/c_str.rs
index 55e58c4e0baa..15dd9ea7e803 100644
--- a/library/core/src/ffi/c_str.rs
+++ b/library/core/src/ffi/c_str.rs
@@ -13,9 +13,9 @@ use crate::str;
 /// array of bytes. It can be constructed safely from a <code>&[[u8]]</code>
 /// slice, or unsafely from a raw `*const c_char`. It can then be
 /// converted to a Rust <code>&[str]</code> by performing UTF-8 validation, or
-/// into an owned `CString`.
+/// into an owned [`CString`].
 ///
-/// `&CStr` is to `CString` as <code>&[str]</code> is to `String`: the former
+/// `&CStr` is to [`CString`] as <code>&[str]</code> is to [`String`]: the former
 /// in each pair are borrowed references; the latter are owned
 /// strings.
 ///
@@ -24,6 +24,9 @@ use crate::str;
 /// functions may leverage the unsafe [`CStr::from_ptr`] constructor to provide
 /// a safe interface to other consumers.
 ///
+/// [`CString`]: ../../std/ffi/struct.CString.html
+/// [`String`]: ../../std/string/struct.String.html
+///
 /// # Examples
 ///
 /// Inspecting a foreign C string:
@@ -221,9 +224,7 @@ impl CStr {
     /// # Examples
     ///
     /// ```ignore (extern-declaration)
-    /// # fn main() {
-    /// use std::ffi::CStr;
-    /// use std::os::raw::c_char;
+    /// use std::ffi::{c_char, CStr};
     ///
     /// extern "C" {
     ///     fn my_string() -> *const c_char;
@@ -233,14 +234,26 @@ impl CStr {
     ///     let slice = CStr::from_ptr(my_string());
     ///     println!("string returned: {}", slice.to_str().unwrap());
     /// }
-    /// # }
+    /// ```
+    ///
+    /// ```
+    /// #![feature(const_cstr_methods)]
+    ///
+    /// use std::ffi::{c_char, CStr};
+    ///
+    /// const HELLO_PTR: *const c_char = {
+    ///     const BYTES: &[u8] = b"Hello, world!\0";
+    ///     BYTES.as_ptr().cast()
+    /// };
+    /// const HELLO: &CStr = unsafe { CStr::from_ptr(HELLO_PTR) };
     /// ```
     ///
     /// [valid]: core::ptr#safety
     #[inline]
     #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub unsafe fn from_ptr<'a>(ptr: *const c_char) -> &'a CStr {
+    #[rustc_const_unstable(feature = "const_cstr_methods", issue = "101719")]
+    pub const unsafe fn from_ptr<'a>(ptr: *const c_char) -> &'a CStr {
         // SAFETY: The caller has provided a pointer that points to a valid C
         // string with a NUL terminator of size less than `isize::MAX`, whose
         // content remain valid and doesn't change for the lifetime of the
@@ -252,13 +265,29 @@ impl CStr {
         //
         // The cast from c_char to u8 is ok because a c_char is always one byte.
         unsafe {
-            extern "C" {
-                /// Provided by libc or compiler_builtins.
-                fn strlen(s: *const c_char) -> usize;
+            const fn strlen_ct(s: *const c_char) -> usize {
+                let mut len = 0;
+
+                // SAFETY: Outer caller has provided a pointer to a valid C string.
+                while unsafe { *s.add(len) } != 0 {
+                    len += 1;
+                }
+
+                len
             }
-            let len = strlen(ptr);
-            let ptr = ptr as *const u8;
-            CStr::from_bytes_with_nul_unchecked(slice::from_raw_parts(ptr, len as usize + 1))
+
+            fn strlen_rt(s: *const c_char) -> usize {
+                extern "C" {
+                    /// Provided by libc or compiler_builtins.
+                    fn strlen(s: *const c_char) -> usize;
+                }
+
+                // SAFETY: Outer caller has provided a pointer to a valid C string.
+                unsafe { strlen(s) }
+            }
+
+            let len = intrinsics::const_eval_select((ptr,), strlen_ct, strlen_rt);
+            Self::from_bytes_with_nul_unchecked(slice::from_raw_parts(ptr.cast(), len + 1))
         }
     }
 
diff --git a/library/core/src/fmt/mod.rs b/library/core/src/fmt/mod.rs
index c8d285505675..2adc968bd469 100644
--- a/library/core/src/fmt/mod.rs
+++ b/library/core/src/fmt/mod.rs
@@ -1054,7 +1054,6 @@ pub trait UpperHex {
 pub trait Pointer {
     /// Formats the value using the given formatter.
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[rustc_diagnostic_item = "pointer_trait_fmt"]
     fn fmt(&self, f: &mut Formatter<'_>) -> Result;
 }
 
diff --git a/library/core/src/future/poll_fn.rs b/library/core/src/future/poll_fn.rs
index db2a523323b7..90cb797391a0 100644
--- a/library/core/src/future/poll_fn.rs
+++ b/library/core/src/future/poll_fn.rs
@@ -5,7 +5,9 @@ use crate::task::{Context, Poll};
 
 /// Creates a future that wraps a function returning [`Poll`].
 ///
-/// Polling the future delegates to the wrapped function.
+/// Polling the future delegates to the wrapped function. If the returned future is pinned, then the
+/// captured environment of the wrapped function is also pinned in-place, so as long as the closure
+/// does not move out of its captures it can soundly create pinned references to them.
 ///
 /// # Examples
 ///
@@ -41,7 +43,7 @@ pub struct PollFn<F> {
 }
 
 #[stable(feature = "future_poll_fn", since = "1.64.0")]
-impl<F> Unpin for PollFn<F> {}
+impl<F: Unpin> Unpin for PollFn<F> {}
 
 #[stable(feature = "future_poll_fn", since = "1.64.0")]
 impl<F> fmt::Debug for PollFn<F> {
@@ -57,7 +59,8 @@ where
 {
     type Output = T;
 
-    fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<T> {
-        (&mut self.f)(cx)
+    fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<T> {
+        // SAFETY: We are not moving out of the pinned field.
+        (unsafe { &mut self.get_unchecked_mut().f })(cx)
     }
 }
diff --git a/library/core/src/hash/mod.rs b/library/core/src/hash/mod.rs
index aa13435e6808..c755afa39eb6 100644
--- a/library/core/src/hash/mod.rs
+++ b/library/core/src/hash/mod.rs
@@ -86,7 +86,8 @@
 #![stable(feature = "rust1", since = "1.0.0")]
 
 use crate::fmt;
-use crate::marker;
+use crate::intrinsics::const_eval_select;
+use crate::marker::{self, Destruct};
 
 #[stable(feature = "rust1", since = "1.0.0")]
 #[allow(deprecated)]
@@ -183,6 +184,7 @@ mod sip;
 /// [impl]: ../../std/primitive.str.html#impl-Hash-for-str
 #[stable(feature = "rust1", since = "1.0.0")]
 #[rustc_diagnostic_item = "Hash"]
+#[const_trait]
 pub trait Hash {
     /// Feeds this value into the given [`Hasher`].
     ///
@@ -234,13 +236,25 @@ pub trait Hash {
     /// [`hash`]: Hash::hash
     /// [`hash_slice`]: Hash::hash_slice
     #[stable(feature = "hash_slice", since = "1.3.0")]
-    fn hash_slice<H: Hasher>(data: &[Self], state: &mut H)
+    fn hash_slice<H: ~const Hasher>(data: &[Self], state: &mut H)
     where
         Self: Sized,
     {
-        for piece in data {
-            piece.hash(state);
+        //FIXME(const_trait_impl): revert to only a for loop
+        fn rt<T: Hash, H: Hasher>(data: &[T], state: &mut H) {
+            for piece in data {
+                piece.hash(state)
+            }
         }
+        const fn ct<T: ~const Hash, H: ~const Hasher>(data: &[T], state: &mut H) {
+            let mut i = 0;
+            while i < data.len() {
+                data[i].hash(state);
+                i += 1;
+            }
+        }
+        // SAFETY: same behavior, CT just uses while instead of for
+        unsafe { const_eval_select((data, state), ct, rt) };
     }
 }
 
@@ -313,6 +327,7 @@ pub use macros::Hash;
 /// [`write_u8`]: Hasher::write_u8
 /// [`write_u32`]: Hasher::write_u32
 #[stable(feature = "rust1", since = "1.0.0")]
+#[const_trait]
 pub trait Hasher {
     /// Returns the hash value for the values written so far.
     ///
@@ -558,7 +573,8 @@ pub trait Hasher {
 }
 
 #[stable(feature = "indirect_hasher_impl", since = "1.22.0")]
-impl<H: Hasher + ?Sized> Hasher for &mut H {
+#[rustc_const_unstable(feature = "const_hash", issue = "104061")]
+impl<H: ~const Hasher + ?Sized> const Hasher for &mut H {
     fn finish(&self) -> u64 {
         (**self).finish()
     }
@@ -638,6 +654,7 @@ impl<H: Hasher + ?Sized> Hasher for &mut H {
 /// [`build_hasher`]: BuildHasher::build_hasher
 /// [`HashMap`]: ../../std/collections/struct.HashMap.html
 #[stable(since = "1.7.0", feature = "build_hasher")]
+#[const_trait]
 pub trait BuildHasher {
     /// Type of the hasher that will be created.
     #[stable(since = "1.7.0", feature = "build_hasher")]
@@ -698,9 +715,10 @@ pub trait BuildHasher {
     /// );
     /// ```
     #[unstable(feature = "build_hasher_simple_hash_one", issue = "86161")]
-    fn hash_one<T: Hash>(&self, x: T) -> u64
+    fn hash_one<T: ~const Hash + ~const Destruct>(&self, x: T) -> u64
     where
         Self: Sized,
+        Self::Hasher: ~const Hasher + ~const Destruct,
     {
         let mut hasher = self.build_hasher();
         x.hash(&mut hasher);
@@ -764,7 +782,8 @@ impl<H> fmt::Debug for BuildHasherDefault<H> {
 }
 
 #[stable(since = "1.7.0", feature = "build_hasher")]
-impl<H: Default + Hasher> BuildHasher for BuildHasherDefault<H> {
+#[rustc_const_unstable(feature = "const_hash", issue = "104061")]
+impl<H: ~const Default + Hasher> const BuildHasher for BuildHasherDefault<H> {
     type Hasher = H;
 
     fn build_hasher(&self) -> H {
@@ -806,14 +825,15 @@ mod impls {
     macro_rules! impl_write {
         ($(($ty:ident, $meth:ident),)*) => {$(
             #[stable(feature = "rust1", since = "1.0.0")]
-            impl Hash for $ty {
+            #[rustc_const_unstable(feature = "const_hash", issue = "104061")]
+            impl const Hash for $ty {
                 #[inline]
-                fn hash<H: Hasher>(&self, state: &mut H) {
+                fn hash<H: ~const Hasher>(&self, state: &mut H) {
                     state.$meth(*self)
                 }
 
                 #[inline]
-                fn hash_slice<H: Hasher>(data: &[$ty], state: &mut H) {
+                fn hash_slice<H: ~const Hasher>(data: &[$ty], state: &mut H) {
                     let newlen = data.len() * mem::size_of::<$ty>();
                     let ptr = data.as_ptr() as *const u8;
                     // SAFETY: `ptr` is valid and aligned, as this macro is only used
@@ -842,33 +862,37 @@ mod impls {
     }
 
     #[stable(feature = "rust1", since = "1.0.0")]
-    impl Hash for bool {
+    #[rustc_const_unstable(feature = "const_hash", issue = "104061")]
+    impl const Hash for bool {
         #[inline]
-        fn hash<H: Hasher>(&self, state: &mut H) {
+        fn hash<H: ~const Hasher>(&self, state: &mut H) {
             state.write_u8(*self as u8)
         }
     }
 
     #[stable(feature = "rust1", since = "1.0.0")]
-    impl Hash for char {
+    #[rustc_const_unstable(feature = "const_hash", issue = "104061")]
+    impl const Hash for char {
         #[inline]
-        fn hash<H: Hasher>(&self, state: &mut H) {
+        fn hash<H: ~const Hasher>(&self, state: &mut H) {
             state.write_u32(*self as u32)
         }
     }
 
     #[stable(feature = "rust1", since = "1.0.0")]
-    impl Hash for str {
+    #[rustc_const_unstable(feature = "const_hash", issue = "104061")]
+    impl const Hash for str {
         #[inline]
-        fn hash<H: Hasher>(&self, state: &mut H) {
+        fn hash<H: ~const Hasher>(&self, state: &mut H) {
             state.write_str(self);
         }
     }
 
     #[stable(feature = "never_hash", since = "1.29.0")]
-    impl Hash for ! {
+    #[rustc_const_unstable(feature = "const_hash", issue = "104061")]
+    impl const Hash for ! {
         #[inline]
-        fn hash<H: Hasher>(&self, _: &mut H) {
+        fn hash<H: ~const Hasher>(&self, _: &mut H) {
             *self
         }
     }
@@ -876,9 +900,10 @@ mod impls {
     macro_rules! impl_hash_tuple {
         () => (
             #[stable(feature = "rust1", since = "1.0.0")]
-            impl Hash for () {
+            #[rustc_const_unstable(feature = "const_hash", issue = "104061")]
+            impl const Hash for () {
                 #[inline]
-                fn hash<H: Hasher>(&self, _state: &mut H) {}
+                fn hash<H: ~const Hasher>(&self, _state: &mut H) {}
             }
         );
 
@@ -886,10 +911,11 @@ mod impls {
             maybe_tuple_doc! {
                 $($name)+ @
                 #[stable(feature = "rust1", since = "1.0.0")]
-                impl<$($name: Hash),+> Hash for ($($name,)+) where last_type!($($name,)+): ?Sized {
+                #[rustc_const_unstable(feature = "const_hash", issue = "104061")]
+                impl<$($name: ~const Hash),+> const Hash for ($($name,)+) where last_type!($($name,)+): ?Sized {
                     #[allow(non_snake_case)]
                     #[inline]
-                    fn hash<S: Hasher>(&self, state: &mut S) {
+                    fn hash<S: ~const Hasher>(&self, state: &mut S) {
                         let ($(ref $name,)+) = *self;
                         $($name.hash(state);)+
                     }
@@ -932,24 +958,27 @@ mod impls {
     impl_hash_tuple! { T B C D E F G H I J K L }
 
     #[stable(feature = "rust1", since = "1.0.0")]
-    impl<T: Hash> Hash for [T] {
+    #[rustc_const_unstable(feature = "const_hash", issue = "104061")]
+    impl<T: ~const Hash> const Hash for [T] {
         #[inline]
-        fn hash<H: Hasher>(&self, state: &mut H) {
+        fn hash<H: ~const Hasher>(&self, state: &mut H) {
             state.write_length_prefix(self.len());
             Hash::hash_slice(self, state)
         }
     }
 
     #[stable(feature = "rust1", since = "1.0.0")]
-    impl<T: ?Sized + Hash> Hash for &T {
+    #[rustc_const_unstable(feature = "const_hash", issue = "104061")]
+    impl<T: ?Sized + ~const Hash> const Hash for &T {
         #[inline]
-        fn hash<H: Hasher>(&self, state: &mut H) {
+        fn hash<H: ~const Hasher>(&self, state: &mut H) {
             (**self).hash(state);
         }
     }
 
     #[stable(feature = "rust1", since = "1.0.0")]
-    impl<T: ?Sized + Hash> Hash for &mut T {
+    #[rustc_const_unstable(feature = "const_hash", issue = "104061")]
+    impl<T: ?Sized + ~const Hash> const Hash for &mut T {
         #[inline]
         fn hash<H: Hasher>(&self, state: &mut H) {
             (**self).hash(state);
diff --git a/library/core/src/hash/sip.rs b/library/core/src/hash/sip.rs
index 81bf1dfdf451..7f8287bf56f6 100644
--- a/library/core/src/hash/sip.rs
+++ b/library/core/src/hash/sip.rs
@@ -118,7 +118,7 @@ macro_rules! load_int_le {
 /// Safety: this performs unchecked indexing of `buf` at `start..start+len`, so
 /// that must be in-bounds.
 #[inline]
-unsafe fn u8to64_le(buf: &[u8], start: usize, len: usize) -> u64 {
+const unsafe fn u8to64_le(buf: &[u8], start: usize, len: usize) -> u64 {
     debug_assert!(len < 8);
     let mut i = 0; // current byte index (from LSB) in the output u64
     let mut out = 0;
@@ -138,7 +138,8 @@ unsafe fn u8to64_le(buf: &[u8], start: usize, len: usize) -> u64 {
         out |= (unsafe { *buf.get_unchecked(start + i) } as u64) << (i * 8);
         i += 1;
     }
-    debug_assert_eq!(i, len);
+    //FIXME(fee1-dead): use debug_assert_eq
+    debug_assert!(i == len);
     out
 }
 
@@ -150,8 +151,9 @@ impl SipHasher {
         since = "1.13.0",
         note = "use `std::collections::hash_map::DefaultHasher` instead"
     )]
+    #[rustc_const_unstable(feature = "const_hash", issue = "104061")]
     #[must_use]
-    pub fn new() -> SipHasher {
+    pub const fn new() -> SipHasher {
         SipHasher::new_with_keys(0, 0)
     }
 
@@ -162,8 +164,9 @@ impl SipHasher {
         since = "1.13.0",
         note = "use `std::collections::hash_map::DefaultHasher` instead"
     )]
+    #[rustc_const_unstable(feature = "const_hash", issue = "104061")]
     #[must_use]
-    pub fn new_with_keys(key0: u64, key1: u64) -> SipHasher {
+    pub const fn new_with_keys(key0: u64, key1: u64) -> SipHasher {
         SipHasher(SipHasher24 { hasher: Hasher::new_with_keys(key0, key1) })
     }
 }
@@ -176,7 +179,8 @@ impl SipHasher13 {
         since = "1.13.0",
         note = "use `std::collections::hash_map::DefaultHasher` instead"
     )]
-    pub fn new() -> SipHasher13 {
+    #[rustc_const_unstable(feature = "const_hash", issue = "104061")]
+    pub const fn new() -> SipHasher13 {
         SipHasher13::new_with_keys(0, 0)
     }
 
@@ -187,14 +191,15 @@ impl SipHasher13 {
         since = "1.13.0",
         note = "use `std::collections::hash_map::DefaultHasher` instead"
     )]
-    pub fn new_with_keys(key0: u64, key1: u64) -> SipHasher13 {
+    #[rustc_const_unstable(feature = "const_hash", issue = "104061")]
+    pub const fn new_with_keys(key0: u64, key1: u64) -> SipHasher13 {
         SipHasher13 { hasher: Hasher::new_with_keys(key0, key1) }
     }
 }
 
 impl<S: Sip> Hasher<S> {
     #[inline]
-    fn new_with_keys(key0: u64, key1: u64) -> Hasher<S> {
+    const fn new_with_keys(key0: u64, key1: u64) -> Hasher<S> {
         let mut state = Hasher {
             k0: key0,
             k1: key1,
@@ -209,7 +214,7 @@ impl<S: Sip> Hasher<S> {
     }
 
     #[inline]
-    fn reset(&mut self) {
+    const fn reset(&mut self) {
         self.length = 0;
         self.state.v0 = self.k0 ^ 0x736f6d6570736575;
         self.state.v1 = self.k1 ^ 0x646f72616e646f6d;
@@ -220,7 +225,8 @@ impl<S: Sip> Hasher<S> {
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
-impl super::Hasher for SipHasher {
+#[rustc_const_unstable(feature = "const_hash", issue = "104061")]
+impl const super::Hasher for SipHasher {
     #[inline]
     fn write(&mut self, msg: &[u8]) {
         self.0.hasher.write(msg)
@@ -238,7 +244,8 @@ impl super::Hasher for SipHasher {
 }
 
 #[unstable(feature = "hashmap_internals", issue = "none")]
-impl super::Hasher for SipHasher13 {
+#[rustc_const_unstable(feature = "const_hash", issue = "104061")]
+impl const super::Hasher for SipHasher13 {
     #[inline]
     fn write(&mut self, msg: &[u8]) {
         self.hasher.write(msg)
@@ -255,7 +262,7 @@ impl super::Hasher for SipHasher13 {
     }
 }
 
-impl<S: Sip> super::Hasher for Hasher<S> {
+impl<S: ~const Sip> const super::Hasher for Hasher<S> {
     // Note: no integer hashing methods (`write_u*`, `write_i*`) are defined
     // for this type. We could add them, copy the `short_write` implementation
     // in librustc_data_structures/sip128.rs, and add `write_u*`/`write_i*`
@@ -335,7 +342,7 @@ impl<S: Sip> super::Hasher for Hasher<S> {
     }
 }
 
-impl<S: Sip> Clone for Hasher<S> {
+impl<S: Sip> const Clone for Hasher<S> {
     #[inline]
     fn clone(&self) -> Hasher<S> {
         Hasher {
@@ -359,6 +366,7 @@ impl<S: Sip> Default for Hasher<S> {
 }
 
 #[doc(hidden)]
+#[const_trait]
 trait Sip {
     fn c_rounds(_: &mut State);
     fn d_rounds(_: &mut State);
@@ -367,7 +375,7 @@ trait Sip {
 #[derive(Debug, Clone, Default)]
 struct Sip13Rounds;
 
-impl Sip for Sip13Rounds {
+impl const Sip for Sip13Rounds {
     #[inline]
     fn c_rounds(state: &mut State) {
         compress!(state);
@@ -384,7 +392,7 @@ impl Sip for Sip13Rounds {
 #[derive(Debug, Clone, Default)]
 struct Sip24Rounds;
 
-impl Sip for Sip24Rounds {
+impl const Sip for Sip24Rounds {
     #[inline]
     fn c_rounds(state: &mut State) {
         compress!(state);
diff --git a/library/core/src/hint.rs b/library/core/src/hint.rs
index 80036bcc4def..c53175ba4f3f 100644
--- a/library/core/src/hint.rs
+++ b/library/core/src/hint.rs
@@ -101,7 +101,7 @@ pub const unsafe fn unreachable_unchecked() -> ! {
     // SAFETY: the safety contract for `intrinsics::unreachable` must
     // be upheld by the caller.
     unsafe {
-        intrinsics::assert_unsafe_precondition!(() => false);
+        intrinsics::assert_unsafe_precondition!("hint::unreachable_unchecked must never be reached", () => false);
         intrinsics::unreachable()
     }
 }
@@ -220,7 +220,7 @@ pub fn spin_loop() {
 ///
 /// [`std::convert::identity`]: crate::convert::identity
 #[inline]
-#[stable(feature = "bench_black_box", since = "CURRENT_RUSTC_VERSION")]
+#[stable(feature = "bench_black_box", since = "1.66.0")]
 #[rustc_const_unstable(feature = "const_black_box", issue = "none")]
 pub const fn black_box<T>(dummy: T) -> T {
     crate::intrinsics::black_box(dummy)
diff --git a/library/core/src/intrinsics.rs b/library/core/src/intrinsics.rs
index 1589fee46bee..819ccf5a3e9e 100644
--- a/library/core/src/intrinsics.rs
+++ b/library/core/src/intrinsics.rs
@@ -55,8 +55,13 @@
 #![allow(missing_docs)]
 
 use crate::marker::DiscriminantKind;
+#[cfg(not(bootstrap))]
+use crate::marker::Tuple;
 use crate::mem;
 
+#[cfg(not(bootstrap))]
+pub mod mir;
+
 // These imports are used for simplifying intra-doc links
 #[allow(unused_imports)]
 #[cfg(all(target_has_atomic = "8", target_has_atomic = "32", target_has_atomic = "ptr"))]
@@ -788,7 +793,7 @@ extern "rust-intrinsic" {
     /// uninitialized at that point in the control flow.
     ///
     /// This intrinsic should not be used outside of the compiler.
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn rustc_peek<T>(_: T) -> T;
 
     /// Aborts the execution of the process.
@@ -806,7 +811,7 @@ extern "rust-intrinsic" {
     /// On Unix, the
     /// process will probably terminate with a signal like `SIGABRT`, `SIGILL`, `SIGTRAP`, `SIGSEGV` or
     /// `SIGBUS`.  The precise behaviour is not guaranteed and not stable.
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn abort() -> !;
 
     /// Informs the optimizer that this point in the code is not reachable,
@@ -845,7 +850,7 @@ extern "rust-intrinsic" {
     ///
     /// This intrinsic does not have a stable counterpart.
     #[rustc_const_unstable(feature = "const_likely", issue = "none")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn likely(b: bool) -> bool;
 
     /// Hints to the compiler that branch condition is likely to be false.
@@ -860,7 +865,7 @@ extern "rust-intrinsic" {
     ///
     /// This intrinsic does not have a stable counterpart.
     #[rustc_const_unstable(feature = "const_likely", issue = "none")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn unlikely(b: bool) -> bool;
 
     /// Executes a breakpoint trap, for inspection by a debugger.
@@ -880,7 +885,7 @@ extern "rust-intrinsic" {
     ///
     /// The stabilized version of this intrinsic is [`core::mem::size_of`].
     #[rustc_const_stable(feature = "const_size_of", since = "1.40.0")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn size_of<T>() -> usize;
 
     /// The minimum alignment of a type.
@@ -892,7 +897,7 @@ extern "rust-intrinsic" {
     ///
     /// The stabilized version of this intrinsic is [`core::mem::align_of`].
     #[rustc_const_stable(feature = "const_min_align_of", since = "1.40.0")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn min_align_of<T>() -> usize;
     /// The preferred alignment of a type.
     ///
@@ -921,7 +926,7 @@ extern "rust-intrinsic" {
     ///
     /// The stabilized version of this intrinsic is [`core::any::type_name`].
     #[rustc_const_unstable(feature = "const_type_name", issue = "63084")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn type_name<T: ?Sized>() -> &'static str;
 
     /// Gets an identifier which is globally unique to the specified type. This
@@ -935,7 +940,7 @@ extern "rust-intrinsic" {
     ///
     /// The stabilized version of this intrinsic is [`core::any::TypeId::of`].
     #[rustc_const_unstable(feature = "const_type_id", issue = "77125")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn type_id<T: ?Sized + 'static>() -> u64;
 
     /// A guard for unsafe functions that cannot ever be executed if `T` is uninhabited:
@@ -943,7 +948,7 @@ extern "rust-intrinsic" {
     ///
     /// This intrinsic does not have a stable counterpart.
     #[rustc_const_stable(feature = "const_assert_type", since = "1.59.0")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn assert_inhabited<T>();
 
     /// A guard for unsafe functions that cannot ever be executed if `T` does not permit
@@ -951,7 +956,7 @@ extern "rust-intrinsic" {
     ///
     /// This intrinsic does not have a stable counterpart.
     #[rustc_const_unstable(feature = "const_assert_type2", issue = "none")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn assert_zero_valid<T>();
 
     /// A guard for unsafe functions that cannot ever be executed if `T` has invalid
@@ -959,7 +964,7 @@ extern "rust-intrinsic" {
     ///
     /// This intrinsic does not have a stable counterpart.
     #[rustc_const_unstable(feature = "const_assert_type2", issue = "none")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn assert_uninit_valid<T>();
 
     /// Gets a reference to a static `Location` indicating where it was called.
@@ -971,7 +976,7 @@ extern "rust-intrinsic" {
     ///
     /// Consider using [`core::panic::Location::caller`] instead.
     #[rustc_const_unstable(feature = "const_caller_location", issue = "76156")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn caller_location() -> &'static crate::panic::Location<'static>;
 
     /// Moves a value out of scope without running drop glue.
@@ -984,7 +989,7 @@ extern "rust-intrinsic" {
     /// Therefore, implementations must not require the user to uphold
     /// any safety invariants.
     #[rustc_const_unstable(feature = "const_intrinsic_forget", issue = "none")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn forget<T: ?Sized>(_: T);
 
     /// Reinterprets the bits of a value of one type as another type.
@@ -1264,7 +1269,7 @@ extern "rust-intrinsic" {
     ///
     /// The stabilized version of this intrinsic is [`mem::needs_drop`](crate::mem::needs_drop).
     #[rustc_const_stable(feature = "const_needs_drop", since = "1.40.0")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn needs_drop<T: ?Sized>() -> bool;
 
     /// Calculates the offset from a pointer.
@@ -1309,7 +1314,7 @@ extern "rust-intrinsic" {
     /// any safety invariants.
     ///
     /// Consider using [`pointer::mask`] instead.
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn ptr_mask<T>(ptr: *const T, mask: usize) -> *const T;
 
     /// Equivalent to the appropriate `llvm.memcpy.p0i8.0i8.*` intrinsic, with
@@ -1501,7 +1506,7 @@ extern "rust-intrinsic" {
     ///
     /// The stabilized version of this intrinsic is
     /// [`f32::min`]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn minnumf32(x: f32, y: f32) -> f32;
     /// Returns the minimum of two `f64` values.
     ///
@@ -1512,7 +1517,7 @@ extern "rust-intrinsic" {
     ///
     /// The stabilized version of this intrinsic is
     /// [`f64::min`]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn minnumf64(x: f64, y: f64) -> f64;
     /// Returns the maximum of two `f32` values.
     ///
@@ -1523,7 +1528,7 @@ extern "rust-intrinsic" {
     ///
     /// The stabilized version of this intrinsic is
     /// [`f32::max`]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn maxnumf32(x: f32, y: f32) -> f32;
     /// Returns the maximum of two `f64` values.
     ///
@@ -1534,7 +1539,7 @@ extern "rust-intrinsic" {
     ///
     /// The stabilized version of this intrinsic is
     /// [`f64::max`]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn maxnumf64(x: f64, y: f64) -> f64;
 
     /// Copies the sign from `y` to `x` for `f32` values.
@@ -1655,7 +1660,7 @@ extern "rust-intrinsic" {
     /// primitives via the `count_ones` method. For example,
     /// [`u32::count_ones`]
     #[rustc_const_stable(feature = "const_ctpop", since = "1.40.0")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn ctpop<T: Copy>(x: T) -> T;
 
     /// Returns the number of leading unset bits (zeroes) in an integer type `T`.
@@ -1693,7 +1698,7 @@ extern "rust-intrinsic" {
     /// assert_eq!(num_leading, 16);
     /// ```
     #[rustc_const_stable(feature = "const_ctlz", since = "1.40.0")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn ctlz<T: Copy>(x: T) -> T;
 
     /// Like `ctlz`, but extra-unsafe as it returns `undef` when
@@ -1750,7 +1755,7 @@ extern "rust-intrinsic" {
     /// assert_eq!(num_trailing, 16);
     /// ```
     #[rustc_const_stable(feature = "const_cttz", since = "1.40.0")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn cttz<T: Copy>(x: T) -> T;
 
     /// Like `cttz`, but extra-unsafe as it returns `undef` when
@@ -1783,7 +1788,7 @@ extern "rust-intrinsic" {
     /// primitives via the `swap_bytes` method. For example,
     /// [`u32::swap_bytes`]
     #[rustc_const_stable(feature = "const_bswap", since = "1.40.0")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn bswap<T: Copy>(x: T) -> T;
 
     /// Reverses the bits in an integer type `T`.
@@ -1797,7 +1802,7 @@ extern "rust-intrinsic" {
     /// primitives via the `reverse_bits` method. For example,
     /// [`u32::reverse_bits`]
     #[rustc_const_stable(feature = "const_bitreverse", since = "1.40.0")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn bitreverse<T: Copy>(x: T) -> T;
 
     /// Performs checked integer addition.
@@ -1811,7 +1816,7 @@ extern "rust-intrinsic" {
     /// primitives via the `overflowing_add` method. For example,
     /// [`u32::overflowing_add`]
     #[rustc_const_stable(feature = "const_int_overflow", since = "1.40.0")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn add_with_overflow<T: Copy>(x: T, y: T) -> (T, bool);
 
     /// Performs checked integer subtraction
@@ -1825,7 +1830,7 @@ extern "rust-intrinsic" {
     /// primitives via the `overflowing_sub` method. For example,
     /// [`u32::overflowing_sub`]
     #[rustc_const_stable(feature = "const_int_overflow", since = "1.40.0")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn sub_with_overflow<T: Copy>(x: T, y: T) -> (T, bool);
 
     /// Performs checked integer multiplication
@@ -1839,7 +1844,7 @@ extern "rust-intrinsic" {
     /// primitives via the `overflowing_mul` method. For example,
     /// [`u32::overflowing_mul`]
     #[rustc_const_stable(feature = "const_int_overflow", since = "1.40.0")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn mul_with_overflow<T: Copy>(x: T, y: T) -> (T, bool);
 
     /// Performs an exact division, resulting in undefined behavior where
@@ -1914,7 +1919,7 @@ extern "rust-intrinsic" {
     /// primitives via the `rotate_left` method. For example,
     /// [`u32::rotate_left`]
     #[rustc_const_stable(feature = "const_int_rotate", since = "1.40.0")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn rotate_left<T: Copy>(x: T, y: T) -> T;
 
     /// Performs rotate right.
@@ -1928,7 +1933,7 @@ extern "rust-intrinsic" {
     /// primitives via the `rotate_right` method. For example,
     /// [`u32::rotate_right`]
     #[rustc_const_stable(feature = "const_int_rotate", since = "1.40.0")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn rotate_right<T: Copy>(x: T, y: T) -> T;
 
     /// Returns (a + b) mod 2<sup>N</sup>, where N is the width of T in bits.
@@ -1942,7 +1947,7 @@ extern "rust-intrinsic" {
     /// primitives via the `wrapping_add` method. For example,
     /// [`u32::wrapping_add`]
     #[rustc_const_stable(feature = "const_int_wrapping", since = "1.40.0")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn wrapping_add<T: Copy>(a: T, b: T) -> T;
     /// Returns (a - b) mod 2<sup>N</sup>, where N is the width of T in bits.
     ///
@@ -1955,7 +1960,7 @@ extern "rust-intrinsic" {
     /// primitives via the `wrapping_sub` method. For example,
     /// [`u32::wrapping_sub`]
     #[rustc_const_stable(feature = "const_int_wrapping", since = "1.40.0")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn wrapping_sub<T: Copy>(a: T, b: T) -> T;
     /// Returns (a * b) mod 2<sup>N</sup>, where N is the width of T in bits.
     ///
@@ -1968,7 +1973,7 @@ extern "rust-intrinsic" {
     /// primitives via the `wrapping_mul` method. For example,
     /// [`u32::wrapping_mul`]
     #[rustc_const_stable(feature = "const_int_wrapping", since = "1.40.0")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn wrapping_mul<T: Copy>(a: T, b: T) -> T;
 
     /// Computes `a + b`, saturating at numeric bounds.
@@ -1982,7 +1987,7 @@ extern "rust-intrinsic" {
     /// primitives via the `saturating_add` method. For example,
     /// [`u32::saturating_add`]
     #[rustc_const_stable(feature = "const_int_saturating", since = "1.40.0")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn saturating_add<T: Copy>(a: T, b: T) -> T;
     /// Computes `a - b`, saturating at numeric bounds.
     ///
@@ -1995,7 +2000,7 @@ extern "rust-intrinsic" {
     /// primitives via the `saturating_sub` method. For example,
     /// [`u32::saturating_sub`]
     #[rustc_const_stable(feature = "const_int_saturating", since = "1.40.0")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn saturating_sub<T: Copy>(a: T, b: T) -> T;
 
     /// Returns the value of the discriminant for the variant in 'v';
@@ -2008,7 +2013,7 @@ extern "rust-intrinsic" {
     ///
     /// The stabilized version of this intrinsic is [`core::mem::discriminant`].
     #[rustc_const_unstable(feature = "const_discriminant", issue = "69821")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn discriminant_value<T>(v: &T) -> <T as DiscriminantKind>::Discriminant;
 
     /// Returns the number of variants of the type `T` cast to a `usize`;
@@ -2021,7 +2026,7 @@ extern "rust-intrinsic" {
     ///
     /// The to-be-stabilized version of this intrinsic is [`mem::variant_count`].
     #[rustc_const_unstable(feature = "variant_count", issue = "73662")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn variant_count<T>() -> usize;
 
     /// Rust's "try catch" construct which invokes the function pointer `try_fn`
@@ -2055,7 +2060,7 @@ extern "rust-intrinsic" {
     /// Therefore, implementations must not require the user to uphold
     /// any safety invariants.
     #[rustc_const_unstable(feature = "const_raw_ptr_comparison", issue = "53020")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn ptr_guaranteed_cmp<T>(ptr: *const T, other: *const T) -> u8;
 
     /// Allocates a block of memory at compile time.
@@ -2106,7 +2111,7 @@ extern "rust-intrinsic" {
     ///
     /// [`std::hint::black_box`]: crate::hint::black_box
     #[rustc_const_unstable(feature = "const_black_box", issue = "none")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
     pub fn black_box<T>(dummy: T) -> T;
 
     /// `ptr` must point to a vtable.
@@ -2169,11 +2174,75 @@ extern "rust-intrinsic" {
     /// `unreachable_unchecked` is actually being reached. The bug is in *crate A*,
     /// which violates the principle that a `const fn` must behave the same at
     /// compile-time and at run-time. The unsafe code in crate B is fine.
+    #[cfg(bootstrap)]
     #[rustc_const_unstable(feature = "const_eval_select", issue = "none")]
     pub fn const_eval_select<ARG, F, G, RET>(arg: ARG, called_in_const: F, called_at_rt: G) -> RET
     where
         G: FnOnce<ARG, Output = RET>,
         F: FnOnce<ARG, Output = RET>;
+
+    /// Selects which function to call depending on the context.
+    ///
+    /// If this function is evaluated at compile-time, then a call to this
+    /// intrinsic will be replaced with a call to `called_in_const`. It gets
+    /// replaced with a call to `called_at_rt` otherwise.
+    ///
+    /// # Type Requirements
+    ///
+    /// The two functions must be both function items. They cannot be function
+    /// pointers or closures. The first function must be a `const fn`.
+    ///
+    /// `arg` will be the tupled arguments that will be passed to either one of
+    /// the two functions, therefore, both functions must accept the same type of
+    /// arguments. Both functions must return RET.
+    ///
+    /// # Safety
+    ///
+    /// The two functions must behave observably equivalent. Safe code in other
+    /// crates may assume that calling a `const fn` at compile-time and at run-time
+    /// produces the same result. A function that produces a different result when
+    /// evaluated at run-time, or has any other observable side-effects, is
+    /// *unsound*.
+    ///
+    /// Here is an example of how this could cause a problem:
+    /// ```no_run
+    /// #![feature(const_eval_select)]
+    /// #![feature(core_intrinsics)]
+    /// use std::hint::unreachable_unchecked;
+    /// use std::intrinsics::const_eval_select;
+    ///
+    /// // Crate A
+    /// pub const fn inconsistent() -> i32 {
+    ///     fn runtime() -> i32 { 1 }
+    ///     const fn compiletime() -> i32 { 2 }
+    ///
+    ///     unsafe {
+    //          // ⚠ This code violates the required equivalence of `compiletime`
+    ///         // and `runtime`.
+    ///         const_eval_select((), compiletime, runtime)
+    ///     }
+    /// }
+    ///
+    /// // Crate B
+    /// const X: i32 = inconsistent();
+    /// let x = inconsistent();
+    /// if x != X { unsafe { unreachable_unchecked(); }}
+    /// ```
+    ///
+    /// This code causes Undefined Behavior when being run, since the
+    /// `unreachable_unchecked` is actually being reached. The bug is in *crate A*,
+    /// which violates the principle that a `const fn` must behave the same at
+    /// compile-time and at run-time. The unsafe code in crate B is fine.
+    #[cfg(not(bootstrap))]
+    #[rustc_const_unstable(feature = "const_eval_select", issue = "none")]
+    pub fn const_eval_select<ARG: Tuple, F, G, RET>(
+        arg: ARG,
+        called_in_const: F,
+        called_at_rt: G,
+    ) -> RET
+    where
+        G: FnOnce<ARG, Output = RET>,
+        F: FnOnce<ARG, Output = RET>;
 }
 
 // Some functions are defined here because they accidentally got made
@@ -2203,7 +2272,7 @@ extern "rust-intrinsic" {
 /// the occasional mistake, and this check should help them figure things out.
 #[allow_internal_unstable(const_eval_select)] // permit this to be called in stably-const fn
 macro_rules! assert_unsafe_precondition {
-    ($([$($tt:tt)*])?($($i:ident:$ty:ty),*$(,)?) => $e:expr) => {
+    ($name:expr, $([$($tt:tt)*])?($($i:ident:$ty:ty),*$(,)?) => $e:expr) => {
         if cfg!(debug_assertions) {
             // allow non_snake_case to allow capturing const generics
             #[allow(non_snake_case)]
@@ -2211,7 +2280,9 @@ macro_rules! assert_unsafe_precondition {
             fn runtime$(<$($tt)*>)?($($i:$ty),*) {
                 if !$e {
                     // don't unwind to reduce impact on code size
-                    ::core::panicking::panic_str_nounwind("unsafe precondition violated");
+                    ::core::panicking::panic_str_nounwind(
+                        concat!("unsafe precondition(s) violated: ", $name)
+                    );
                 }
             }
             #[allow(non_snake_case)]
@@ -2229,6 +2300,16 @@ pub(crate) fn is_aligned_and_not_null<T>(ptr: *const T) -> bool {
     !ptr.is_null() && ptr.is_aligned()
 }
 
+/// Checks whether an allocation of `len` instances of `T` exceeds
+/// the maximum allowed allocation size.
+pub(crate) fn is_valid_allocation_size<T>(len: usize) -> bool {
+    let max_len = const {
+        let size = crate::mem::size_of::<T>();
+        if size == 0 { usize::MAX } else { isize::MAX as usize / size }
+    };
+    len <= max_len
+}
+
 /// Checks whether the regions of memory starting at `src` and `dst` of size
 /// `count * size_of::<T>()` do *not* overlap.
 pub(crate) fn is_nonoverlapping<T>(src: *const T, dst: *const T, count: usize) -> bool {
@@ -2340,7 +2421,10 @@ pub const unsafe fn copy_nonoverlapping<T>(src: *const T, dst: *mut T, count: us
     // SAFETY: the safety contract for `copy_nonoverlapping` must be
     // upheld by the caller.
     unsafe {
-        assert_unsafe_precondition!([T](src: *const T, dst: *mut T, count: usize) =>
+        assert_unsafe_precondition!(
+            "ptr::copy_nonoverlapping requires that both pointer arguments are aligned and non-null \
+            and the specified memory ranges do not overlap",
+            [T](src: *const T, dst: *mut T, count: usize) =>
             is_aligned_and_not_null(src)
                 && is_aligned_and_not_null(dst)
                 && is_nonoverlapping(src, dst, count)
@@ -2426,8 +2510,11 @@ pub const unsafe fn copy<T>(src: *const T, dst: *mut T, count: usize) {
 
     // SAFETY: the safety contract for `copy` must be upheld by the caller.
     unsafe {
-        assert_unsafe_precondition!([T](src: *const T, dst: *mut T) =>
-            is_aligned_and_not_null(src) && is_aligned_and_not_null(dst));
+        assert_unsafe_precondition!(
+            "ptr::copy requires that both pointer arguments are aligned aligned and non-null",
+            [T](src: *const T, dst: *mut T) =>
+            is_aligned_and_not_null(src) && is_aligned_and_not_null(dst)
+        );
         copy(src, dst, count)
     }
 }
@@ -2495,7 +2582,10 @@ pub const unsafe fn write_bytes<T>(dst: *mut T, val: u8, count: usize) {
 
     // SAFETY: the safety contract for `write_bytes` must be upheld by the caller.
     unsafe {
-        assert_unsafe_precondition!([T](dst: *mut T) => is_aligned_and_not_null(dst));
+        assert_unsafe_precondition!(
+            "ptr::write_bytes requires that the destination pointer is aligned and non-null",
+            [T](dst: *mut T) => is_aligned_and_not_null(dst)
+        );
         write_bytes(dst, val, count)
     }
 }
diff --git a/library/core/src/intrinsics/mir.rs b/library/core/src/intrinsics/mir.rs
new file mode 100644
index 000000000000..1bacdc39148a
--- /dev/null
+++ b/library/core/src/intrinsics/mir.rs
@@ -0,0 +1,123 @@
+//! Rustc internal tooling for hand-writing MIR.
+//!
+//! If for some reasons you are not writing rustc tests and have found yourself considering using
+//! this feature, turn back. This is *exceptionally* unstable. There is no attempt at all to make
+//! anything work besides those things which the rustc test suite happened to need. If you make a
+//! typo you'll probably ICE. Really, this is not the solution to your problems. Consider instead
+//! supporting the [stable MIR project group](https://github.com/rust-lang/project-stable-mir).
+//!
+//! The documentation for this module describes how to use this feature. If you are interested in
+//! hacking on the implementation, most of that documentation lives at
+//! `rustc_mir_building/src/build/custom/mod.rs`.
+//!
+//! Typical usage will look like this:
+//!
+//! ```rust
+//! #![feature(core_intrinsics, custom_mir)]
+//!
+//! extern crate core;
+//! use core::intrinsics::mir::*;
+//!
+//! #[custom_mir(dialect = "built")]
+//! pub fn simple(x: i32) -> i32 {
+//!     mir!(
+//!         let temp1: i32;
+//!         let temp2: _;
+//!
+//!         {
+//!             temp1 = x;
+//!             Goto(exit)
+//!         }
+//!
+//!         exit = {
+//!             temp2 = Move(temp1);
+//!             RET = temp2;
+//!             Return()
+//!         }
+//!     )
+//! }
+//! ```
+//!
+//! Hopefully most of this is fairly self-explanatory. Expanding on some notable details:
+//!
+//!  - The `custom_mir` attribute tells the compiler to treat the function as being custom MIR. This
+//!    attribute only works on functions - there is no way to insert custom MIR into the middle of
+//!    another function.
+//!  - The `dialect` and `phase` parameters indicate which version of MIR you are inserting here.
+//!    This will normally be the phase that corresponds to the thing you are trying to test. The
+//!    phase can be omitted for dialects that have just one.
+//!  - You should define your function signature like you normally would. Externally, this function
+//!    can be called like any other function.
+//!  - Type inference works - you don't have to spell out the type of all of your locals.
+//!
+//! For now, all statements and terminators are parsed from nested invocations of the special
+//! functions provided in this module. We additionally want to (but do not yet) support more
+//! "normal" Rust syntax in places where it makes sense. Also, most kinds of instructions are not
+//! supported yet.
+//!
+
+#![unstable(
+    feature = "custom_mir",
+    reason = "MIR is an implementation detail and extremely unstable",
+    issue = "none"
+)]
+#![allow(unused_variables, non_snake_case, missing_debug_implementations)]
+
+/// Type representing basic blocks.
+///
+/// All terminators will have this type as a return type. It helps achieve some type safety.
+pub struct BasicBlock;
+
+macro_rules! define {
+    ($name:literal, $($sig:tt)*) => {
+        #[rustc_diagnostic_item = $name]
+        pub $($sig)* { panic!() }
+    }
+}
+
+define!("mir_return", fn Return() -> BasicBlock);
+define!("mir_goto", fn Goto(destination: BasicBlock) -> BasicBlock);
+define!("mir_retag", fn Retag<T>(place: T));
+define!("mir_retag_raw", fn RetagRaw<T>(place: T));
+define!("mir_move", fn Move<T>(place: T) -> T);
+
+/// Convenience macro for generating custom MIR.
+///
+/// See the module documentation for syntax details. This macro is not magic - it only transforms
+/// your MIR into something that is easier to parse in the compiler.
+#[rustc_macro_transparency = "transparent"]
+pub macro mir {
+    (
+        $(let $local_decl:ident $(: $local_decl_ty:ty)? ;)*
+
+        $entry_block:block
+
+        $(
+            $block_name:ident = $block:block
+        )*
+    ) => {{
+        // First, we declare all basic blocks.
+        $(
+            let $block_name: ::core::intrinsics::mir::BasicBlock;
+        )*
+
+        {
+            // Now all locals
+            #[allow(non_snake_case)]
+            let RET;
+            $(
+                let $local_decl $(: $local_decl_ty)? ;
+            )*
+
+            {
+                // Finally, the contents of the basic blocks
+                $entry_block;
+                $(
+                    $block;
+                )*
+
+                RET
+            }
+        }
+    }}
+}
diff --git a/library/core/src/iter/adapters/array_chunks.rs b/library/core/src/iter/adapters/array_chunks.rs
index d4fb886101fe..5e4211058aa6 100644
--- a/library/core/src/iter/adapters/array_chunks.rs
+++ b/library/core/src/iter/adapters/array_chunks.rs
@@ -1,6 +1,8 @@
 use crate::array;
-use crate::iter::{ByRefSized, FusedIterator, Iterator};
-use crate::ops::{ControlFlow, Try};
+use crate::const_closure::ConstFnMutClosure;
+use crate::iter::{ByRefSized, FusedIterator, Iterator, TrustedRandomAccessNoCoerce};
+use crate::mem::{self, MaybeUninit};
+use crate::ops::{ControlFlow, NeverShortCircuit, Try};
 
 /// An iterator over `N` elements of the iterator at a time.
 ///
@@ -82,7 +84,13 @@ where
         }
     }
 
-    impl_fold_via_try_fold! { fold -> try_fold }
+    fn fold<B, F>(self, init: B, f: F) -> B
+    where
+        Self: Sized,
+        F: FnMut(B, Self::Item) -> B,
+    {
+        <Self as SpecFold>::fold(self, init, f)
+    }
 }
 
 #[unstable(feature = "iter_array_chunks", reason = "recently added", issue = "100450")]
@@ -168,3 +176,64 @@ where
         self.iter.len() < N
     }
 }
+
+trait SpecFold: Iterator {
+    fn fold<B, F>(self, init: B, f: F) -> B
+    where
+        Self: Sized,
+        F: FnMut(B, Self::Item) -> B;
+}
+
+impl<I, const N: usize> SpecFold for ArrayChunks<I, N>
+where
+    I: Iterator,
+{
+    #[inline]
+    default fn fold<B, F>(mut self, init: B, mut f: F) -> B
+    where
+        Self: Sized,
+        F: FnMut(B, Self::Item) -> B,
+    {
+        let fold = ConstFnMutClosure::new(&mut f, NeverShortCircuit::wrap_mut_2_imp);
+        self.try_fold(init, fold).0
+    }
+}
+
+impl<I, const N: usize> SpecFold for ArrayChunks<I, N>
+where
+    I: Iterator + TrustedRandomAccessNoCoerce,
+{
+    #[inline]
+    fn fold<B, F>(mut self, init: B, mut f: F) -> B
+    where
+        Self: Sized,
+        F: FnMut(B, Self::Item) -> B,
+    {
+        let mut accum = init;
+        let inner_len = self.iter.size();
+        let mut i = 0;
+        // Use a while loop because (0..len).step_by(N) doesn't optimize well.
+        while inner_len - i >= N {
+            let mut chunk = MaybeUninit::uninit_array();
+            let mut guard = array::Guard { array_mut: &mut chunk, initialized: 0 };
+            while guard.initialized < N {
+                // SAFETY: The method consumes the iterator and the loop condition ensures that
+                // all accesses are in bounds and only happen once.
+                unsafe {
+                    let idx = i + guard.initialized;
+                    guard.push_unchecked(self.iter.__iterator_get_unchecked(idx));
+                }
+            }
+            mem::forget(guard);
+            // SAFETY: The loop above initialized all elements
+            let chunk = unsafe { MaybeUninit::array_assume_init(chunk) };
+            accum = f(accum, chunk);
+            i += N;
+        }
+
+        // unlike try_fold this method does not need to take care of the remainder
+        // since `self` will be dropped
+
+        accum
+    }
+}
diff --git a/library/core/src/iter/traits/iterator.rs b/library/core/src/iter/traits/iterator.rs
index 789a87968d15..83c7e8977e9f 100644
--- a/library/core/src/iter/traits/iterator.rs
+++ b/library/core/src/iter/traits/iterator.rs
@@ -14,7 +14,7 @@ use super::super::{
 
 fn _assert_is_object_safe(_: &dyn Iterator<Item = ()>) {}
 
-/// An interface for dealing with iterators.
+/// A trait for dealing with iterators.
 ///
 /// This is the main iterator trait. For more about the concept of iterators
 /// generally, please see the [module-level documentation]. In particular, you
diff --git a/library/core/src/lib.rs b/library/core/src/lib.rs
index 9cbfbbb9f399..2d12805270f9 100644
--- a/library/core/src/lib.rs
+++ b/library/core/src/lib.rs
@@ -104,7 +104,7 @@
 #![feature(const_black_box)]
 #![feature(const_caller_location)]
 #![feature(const_cell_into_inner)]
-#![feature(const_char_convert)]
+#![feature(const_char_from_u32_unchecked)]
 #![feature(const_clone)]
 #![feature(const_cmp)]
 #![feature(const_discriminant)]
@@ -112,6 +112,7 @@
 #![feature(const_float_bits_conv)]
 #![feature(const_float_classify)]
 #![feature(const_fmt_arguments_new)]
+#![feature(const_hash)]
 #![feature(const_heap)]
 #![feature(const_convert)]
 #![feature(const_index_range_slice_index)]
@@ -184,6 +185,7 @@
 #![feature(const_refs_to_cell)]
 #![feature(decl_macro)]
 #![feature(deprecated_suggestion)]
+#![cfg_attr(not(bootstrap), feature(derive_const))]
 #![feature(doc_cfg)]
 #![feature(doc_notable_trait)]
 #![feature(rustdoc_internals)]
@@ -192,6 +194,7 @@
 #![feature(extern_types)]
 #![feature(fundamental)]
 #![feature(if_let_guard)]
+#![feature(inline_const)]
 #![feature(intra_doc_pointers)]
 #![feature(intrinsics)]
 #![feature(lang_items)]
diff --git a/library/core/src/macros/mod.rs b/library/core/src/macros/mod.rs
index fd96e1ff77d5..34247c058450 100644
--- a/library/core/src/macros/mod.rs
+++ b/library/core/src/macros/mod.rs
@@ -338,7 +338,6 @@ pub macro debug_assert_matches($($arg:tt)*) {
 /// ```
 #[macro_export]
 #[stable(feature = "matches_macro", since = "1.42.0")]
-#[cfg_attr(not(test), rustc_diagnostic_item = "matches_macro")]
 macro_rules! matches {
     ($expression:expr, $(|)? $( $pattern:pat_param )|+ $( if $guard: expr )? $(,)?) => {
         match $expression {
@@ -820,7 +819,6 @@ pub(crate) mod builtin {
     #[stable(feature = "compile_error_macro", since = "1.20.0")]
     #[rustc_builtin_macro]
     #[macro_export]
-    #[cfg_attr(not(test), rustc_diagnostic_item = "compile_error_macro")]
     macro_rules! compile_error {
         ($msg:expr $(,)?) => {{ /* compiler built-in */ }};
     }
@@ -944,7 +942,6 @@ pub(crate) mod builtin {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_builtin_macro]
     #[macro_export]
-    #[cfg_attr(not(test), rustc_diagnostic_item = "env_macro")]
     macro_rules! env {
         ($name:expr $(,)?) => {{ /* compiler built-in */ }};
         ($name:expr, $error_msg:expr $(,)?) => {{ /* compiler built-in */ }};
@@ -973,7 +970,6 @@ pub(crate) mod builtin {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_builtin_macro]
     #[macro_export]
-    #[cfg_attr(not(test), rustc_diagnostic_item = "option_env_macro")]
     macro_rules! option_env {
         ($name:expr $(,)?) => {{ /* compiler built-in */ }};
     }
@@ -1058,7 +1054,6 @@ pub(crate) mod builtin {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_builtin_macro]
     #[macro_export]
-    #[cfg_attr(not(test), rustc_diagnostic_item = "concat_macro")]
     macro_rules! concat {
         ($($e:expr),* $(,)?) => {{ /* compiler built-in */ }};
     }
@@ -1084,7 +1079,6 @@ pub(crate) mod builtin {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_builtin_macro]
     #[macro_export]
-    #[cfg_attr(not(test), rustc_diagnostic_item = "line_macro")]
     macro_rules! line {
         () => {
             /* compiler built-in */
@@ -1124,7 +1118,6 @@ pub(crate) mod builtin {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_builtin_macro]
     #[macro_export]
-    #[cfg_attr(not(test), rustc_diagnostic_item = "column_macro")]
     macro_rules! column {
         () => {
             /* compiler built-in */
@@ -1150,7 +1143,6 @@ pub(crate) mod builtin {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_builtin_macro]
     #[macro_export]
-    #[cfg_attr(not(test), rustc_diagnostic_item = "file_macro")]
     macro_rules! file {
         () => {
             /* compiler built-in */
@@ -1175,7 +1167,6 @@ pub(crate) mod builtin {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_builtin_macro]
     #[macro_export]
-    #[cfg_attr(not(test), rustc_diagnostic_item = "stringify_macro")]
     macro_rules! stringify {
         ($($t:tt)*) => {
             /* compiler built-in */
@@ -1282,7 +1273,6 @@ pub(crate) mod builtin {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_builtin_macro]
     #[macro_export]
-    #[cfg_attr(not(test), rustc_diagnostic_item = "module_path_macro")]
     macro_rules! module_path {
         () => {
             /* compiler built-in */
@@ -1316,7 +1306,6 @@ pub(crate) mod builtin {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_builtin_macro]
     #[macro_export]
-    #[cfg_attr(not(test), rustc_diagnostic_item = "cfg_macro")]
     macro_rules! cfg {
         ($($cfg:tt)*) => {
             /* compiler built-in */
@@ -1367,7 +1356,6 @@ pub(crate) mod builtin {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_builtin_macro]
     #[macro_export]
-    #[cfg_attr(not(test), rustc_diagnostic_item = "include_macro")]
     macro_rules! include {
         ($file:expr $(,)?) => {{ /* compiler built-in */ }};
     }
@@ -1464,6 +1452,19 @@ pub(crate) mod builtin {
         /* compiler built-in */
     }
 
+    /// Attribute macro used to apply derive macros for implementing traits
+    /// in a const context.
+    ///
+    /// See [the reference] for more info.
+    ///
+    /// [the reference]: ../../../reference/attributes/derive.html
+    #[unstable(feature = "derive_const", issue = "none")]
+    #[rustc_builtin_macro]
+    #[cfg(not(bootstrap))]
+    pub macro derive_const($item:item) {
+        /* compiler built-in */
+    }
+
     /// Attribute macro applied to a function to turn it into a unit test.
     ///
     /// See [the reference] for more info.
@@ -1511,6 +1512,17 @@ pub(crate) mod builtin {
         /* compiler built-in */
     }
 
+    /// Attribute macro applied to a function to register it as a handler for allocation failure.
+    ///
+    /// See also [`std::alloc::handle_alloc_error`](../../../std/alloc/fn.handle_alloc_error.html).
+    #[cfg(not(bootstrap))]
+    #[unstable(feature = "alloc_error_handler", issue = "51540")]
+    #[allow_internal_unstable(rustc_attrs)]
+    #[rustc_builtin_macro]
+    pub macro alloc_error_handler($item:item) {
+        /* compiler built-in */
+    }
+
     /// Keeps the item it's applied to if the passed path is accessible, and removes it otherwise.
     #[unstable(
         feature = "cfg_accessible",
diff --git a/library/core/src/marker.rs b/library/core/src/marker.rs
index c43c4fff6ae7..3eff6033f8da 100644
--- a/library/core/src/marker.rs
+++ b/library/core/src/marker.rs
@@ -44,6 +44,12 @@ impl<T: ?Sized> !Send for *const T {}
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<T: ?Sized> !Send for *mut T {}
 
+// Most instances arise automatically, but this instance is needed to link up `T: Sync` with
+// `&T: Send` (and it also removes the unsound default instance `T Send` -> `&T: Send` that would
+// otherwise exist).
+#[stable(feature = "rust1", since = "1.0.0")]
+unsafe impl<T: Sync + ?Sized> Send for &T {}
+
 /// Types with a constant size known at compile time.
 ///
 /// All type parameters have an implicit bound of `Sized`. The special syntax
@@ -90,6 +96,7 @@ impl<T: ?Sized> !Send for *mut T {}
 )]
 #[fundamental] // for Default, for example, which requires that `[T]: !Default` be evaluatable
 #[rustc_specialization_trait]
+#[cfg_attr(not(bootstrap), rustc_deny_explicit_impl)]
 pub trait Sized {
     // Empty.
 }
@@ -121,6 +128,7 @@ pub trait Sized {
 /// [nomicon-coerce]: ../../nomicon/coercions.html
 #[unstable(feature = "unsize", issue = "27732")]
 #[lang = "unsize"]
+#[cfg_attr(not(bootstrap), rustc_deny_explicit_impl)]
 pub trait Unsize<T: ?Sized> {
     // Empty.
 }
@@ -674,13 +682,6 @@ impl<T: ?Sized> StructuralPartialEq for PhantomData<T> {}
 #[unstable(feature = "structural_match", issue = "31434")]
 impl<T: ?Sized> StructuralEq for PhantomData<T> {}
 
-mod impls {
-    #[stable(feature = "rust1", since = "1.0.0")]
-    unsafe impl<T: Sync + ?Sized> Send for &T {}
-    #[stable(feature = "rust1", since = "1.0.0")]
-    unsafe impl<T: Send + ?Sized> Send for &mut T {}
-}
-
 /// Compiler-internal trait used to indicate the type of enum discriminants.
 ///
 /// This trait is automatically implemented for every type and does not add any
@@ -694,6 +695,7 @@ mod impls {
     reason = "this trait is unlikely to ever be stabilized, use `mem::discriminant` instead"
 )]
 #[lang = "discriminant_kind"]
+#[cfg_attr(not(bootstrap), rustc_deny_explicit_impl)]
 pub trait DiscriminantKind {
     /// The type of the discriminant, which must satisfy the trait
     /// bounds required by `mem::Discriminant`.
@@ -794,6 +796,7 @@ impl<T: ?Sized> Unpin for *mut T {}
 #[lang = "destruct"]
 #[rustc_on_unimplemented(message = "can't drop `{Self}`", append_const_msg)]
 #[const_trait]
+#[cfg_attr(not(bootstrap), rustc_deny_explicit_impl)]
 pub trait Destruct {}
 
 /// A marker for tuple types.
@@ -803,6 +806,7 @@ pub trait Destruct {}
 #[unstable(feature = "tuple_trait", issue = "none")]
 #[lang = "tuple_trait"]
 #[rustc_on_unimplemented(message = "`{Self}` is not a tuple")]
+#[cfg_attr(not(bootstrap), rustc_deny_explicit_impl)]
 pub trait Tuple {}
 
 /// Implementations of `Copy` for primitive types.
diff --git a/library/core/src/mem/maybe_uninit.rs b/library/core/src/mem/maybe_uninit.rs
index 7757c95de9d2..3f491836551d 100644
--- a/library/core/src/mem/maybe_uninit.rs
+++ b/library/core/src/mem/maybe_uninit.rs
@@ -1172,7 +1172,7 @@ impl<T> MaybeUninit<T> {
     /// #![feature(maybe_uninit_as_bytes, maybe_uninit_slice)]
     /// use std::mem::MaybeUninit;
     ///
-    /// let val = 0x12345678i32;
+    /// let val = 0x12345678_i32;
     /// let uninit = MaybeUninit::new(val);
     /// let uninit_bytes = uninit.as_bytes();
     /// let bytes = unsafe { MaybeUninit::slice_assume_init_ref(uninit_bytes) };
@@ -1198,7 +1198,7 @@ impl<T> MaybeUninit<T> {
     /// #![feature(maybe_uninit_as_bytes)]
     /// use std::mem::MaybeUninit;
     ///
-    /// let val = 0x12345678i32;
+    /// let val = 0x12345678_i32;
     /// let mut uninit = MaybeUninit::new(val);
     /// let uninit_bytes = uninit.as_bytes_mut();
     /// if cfg!(target_endian = "little") {
diff --git a/library/core/src/mem/mod.rs b/library/core/src/mem/mod.rs
index 9195da5a44f4..956a69eda8a5 100644
--- a/library/core/src/mem/mod.rs
+++ b/library/core/src/mem/mod.rs
@@ -21,11 +21,6 @@ mod maybe_uninit;
 #[stable(feature = "maybe_uninit", since = "1.36.0")]
 pub use maybe_uninit::MaybeUninit;
 
-// FIXME: This is left here for now to avoid complications around pending reverts.
-// Once <https://github.com/rust-lang/rust/issues/101899> is fully resolved,
-// this should be removed and the references in `alloc::Layout` updated.
-pub(crate) use ptr::Alignment as ValidAlign;
-
 mod transmutability;
 #[unstable(feature = "transmutability", issue = "99571")]
 pub use transmutability::{Assume, BikeshedIntrinsicFrom};
@@ -1004,7 +999,7 @@ pub fn drop<T>(_x: T) {}
 /// ```
 #[inline]
 #[unstable(feature = "mem_copy_fn", issue = "98262")]
-pub fn copy<T: Copy>(x: &T) -> T {
+pub const fn copy<T: Copy>(x: &T) -> T {
     *x
 }
 
diff --git a/library/core/src/num/int_macros.rs b/library/core/src/num/int_macros.rs
index 81f050cb283d..e64eb1cf7aed 100644
--- a/library/core/src/num/int_macros.rs
+++ b/library/core/src/num/int_macros.rs
@@ -107,6 +107,9 @@ macro_rules! int_impl {
 
         /// Returns the number of leading zeros in the binary representation of `self`.
         ///
+        /// Depending on what you're doing with the value, you might also be interested in the
+        /// [`ilog2`] function which returns a consistent number, even if the type widens.
+        ///
         /// # Examples
         ///
         /// Basic usage:
@@ -116,6 +119,7 @@ macro_rules! int_impl {
         ///
         /// assert_eq!(n.leading_zeros(), 0);
         /// ```
+        #[doc = concat!("[`ilog2`]: ", stringify!($SelfT), "::ilog2")]
         #[stable(feature = "rust1", since = "1.0.0")]
         #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
         #[must_use = "this returns the result of the operation, \
@@ -467,8 +471,8 @@ macro_rules! int_impl {
         #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_add_unsigned(2), Some(3));")]
         #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).checked_add_unsigned(3), None);")]
         /// ```
-        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
-        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -535,8 +539,8 @@ macro_rules! int_impl {
         #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_sub_unsigned(2), Some(-1));")]
         #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 2).checked_sub_unsigned(3), None);")]
         /// ```
-        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
-        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -905,8 +909,8 @@ macro_rules! int_impl {
         #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".saturating_add_unsigned(2), 3);")]
         #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.saturating_add_unsigned(100), ", stringify!($SelfT), "::MAX);")]
         /// ```
-        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
-        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -951,8 +955,8 @@ macro_rules! int_impl {
         #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".saturating_sub_unsigned(127), -27);")]
         #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.saturating_sub_unsigned(100), ", stringify!($SelfT), "::MIN);")]
         /// ```
-        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
-        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -1129,8 +1133,8 @@ macro_rules! int_impl {
         #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_add_unsigned(27), 127);")]
         #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.wrapping_add_unsigned(2), ", stringify!($SelfT), "::MIN + 1);")]
         /// ```
-        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
-        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
@@ -1169,8 +1173,8 @@ macro_rules! int_impl {
         #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".wrapping_sub_unsigned(127), -127);")]
         #[doc = concat!("assert_eq!((-2", stringify!($SelfT), ").wrapping_sub_unsigned(", stringify!($UnsignedT), "::MAX), -1);")]
         /// ```
-        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
-        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
@@ -1566,8 +1570,8 @@ macro_rules! int_impl {
         #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN).overflowing_add_unsigned(", stringify!($UnsignedT), "::MAX), (", stringify!($SelfT), "::MAX, false));")]
         #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).overflowing_add_unsigned(3), (", stringify!($SelfT), "::MIN, true));")]
         /// ```
-        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
-        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -1648,8 +1652,8 @@ macro_rules! int_impl {
         #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX).overflowing_sub_unsigned(", stringify!($UnsignedT), "::MAX), (", stringify!($SelfT), "::MIN, false));")]
         #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 2).overflowing_sub_unsigned(3), (", stringify!($SelfT), "::MAX, true));")]
         /// ```
-        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
-        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -2068,11 +2072,15 @@ macro_rules! int_impl {
         pub const fn rem_euclid(self, rhs: Self) -> Self {
             let r = self % rhs;
             if r < 0 {
-                if rhs < 0 {
-                    r - rhs
-                } else {
-                    r + rhs
-                }
+                // Semantically equivalent to `if rhs < 0 { r - rhs } else { r + rhs }`.
+                // If `rhs` is not `Self::MIN`, then `r + abs(rhs)` will not overflow
+                // and is clearly equivalent, because `r` is negative.
+                // Otherwise, `rhs` is `Self::MIN`, then we have
+                // `r.wrapping_add(Self::MIN.wrapping_abs())`, which evaluates
+                // to `r.wrapping_add(Self::MIN)`, which is equivalent to
+                // `r - Self::MIN`, which is what we wanted (and will not overflow
+                // for negative `r`).
+                r.wrapping_add(rhs.wrapping_abs())
             } else {
                 r
             }
@@ -2271,15 +2279,16 @@ macro_rules! int_impl {
         /// # Panics
         ///
         /// This function will panic if `self` is less than or equal to zero,
-        /// or if `base` is less then 2.
+        /// or if `base` is less than 2.
         ///
         /// # Examples
         ///
         /// ```
-        /// #![feature(int_log)]
         #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".ilog(5), 1);")]
         /// ```
-        #[unstable(feature = "int_log", issue = "70887")]
+        #[stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_allow_const_fn_unstable(const_option)]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -2298,10 +2307,11 @@ macro_rules! int_impl {
         /// # Examples
         ///
         /// ```
-        /// #![feature(int_log)]
         #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".ilog2(), 1);")]
         /// ```
-        #[unstable(feature = "int_log", issue = "70887")]
+        #[stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_allow_const_fn_unstable(const_option)]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -2319,10 +2329,11 @@ macro_rules! int_impl {
         /// # Example
         ///
         /// ```
-        /// #![feature(int_log)]
         #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".ilog10(), 1);")]
         /// ```
-        #[unstable(feature = "int_log", issue = "70887")]
+        #[stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_allow_const_fn_unstable(const_option)]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -2343,10 +2354,10 @@ macro_rules! int_impl {
         /// # Examples
         ///
         /// ```
-        /// #![feature(int_log)]
         #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_ilog(5), Some(1));")]
         /// ```
-        #[unstable(feature = "int_log", issue = "70887")]
+        #[stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -2379,10 +2390,10 @@ macro_rules! int_impl {
         /// # Examples
         ///
         /// ```
-        /// #![feature(int_log)]
         #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".checked_ilog2(), Some(1));")]
         /// ```
-        #[unstable(feature = "int_log", issue = "70887")]
+        #[stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -2403,10 +2414,10 @@ macro_rules! int_impl {
         /// # Example
         ///
         /// ```
-        /// #![feature(int_log)]
         #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".checked_ilog10(), Some(1));")]
         /// ```
-        #[unstable(feature = "int_log", issue = "70887")]
+        #[stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
diff --git a/library/core/src/num/nonzero.rs b/library/core/src/num/nonzero.rs
index da402d66502a..6a417b54daa9 100644
--- a/library/core/src/num/nonzero.rs
+++ b/library/core/src/num/nonzero.rs
@@ -56,7 +56,10 @@ macro_rules! nonzero_integers {
                 pub const unsafe fn new_unchecked(n: $Int) -> Self {
                     // SAFETY: this is guaranteed to be safe by the caller.
                     unsafe {
-                        core::intrinsics::assert_unsafe_precondition!((n: $Int) => n != 0);
+                        core::intrinsics::assert_unsafe_precondition!(
+                            concat!(stringify!($Ty), "::new_unchecked requires a non-zero argument"),
+                            (n: $Int) => n != 0
+                        );
                         Self(n)
                     }
                 }
@@ -318,7 +321,6 @@ macro_rules! nonzero_unsigned_operations {
                 ///
                 /// ```
                 #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
-                ///
                 /// # fn main() { test().unwrap(); }
                 /// # fn test() -> Option<()> {
                 #[doc = concat!("let one = ", stringify!($Ty), "::new(1)?;")]
@@ -353,7 +355,6 @@ macro_rules! nonzero_unsigned_operations {
                 ///
                 /// ```
                 #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
-                ///
                 /// # fn main() { test().unwrap(); }
                 /// # fn test() -> Option<()> {
                 #[doc = concat!("let one = ", stringify!($Ty), "::new(1)?;")]
@@ -388,8 +389,8 @@ macro_rules! nonzero_unsigned_operations {
                 ///
                 /// ```
                 /// #![feature(nonzero_ops)]
-                #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
                 ///
+                #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
                 /// # fn main() { test().unwrap(); }
                 /// # fn test() -> Option<()> {
                 #[doc = concat!("let one = ", stringify!($Ty), "::new(1)?;")]
@@ -417,7 +418,6 @@ macro_rules! nonzero_unsigned_operations {
                 ///
                 /// ```
                 #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
-                ///
                 /// # fn main() { test().unwrap(); }
                 /// # fn test() -> Option<()> {
                 #[doc = concat!("let two = ", stringify!($Ty), "::new(2)?;")]
@@ -457,14 +457,13 @@ macro_rules! nonzero_unsigned_operations {
                 /// # Examples
                 ///
                 /// ```
-                /// #![feature(int_log)]
                 #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
-                ///
                 #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(7).unwrap().ilog2(), 2);")]
                 #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(8).unwrap().ilog2(), 3);")]
                 #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(9).unwrap().ilog2(), 3);")]
                 /// ```
-                #[unstable(feature = "int_log", issue = "70887")]
+                #[stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
+                #[rustc_const_stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
                 #[must_use = "this returns the result of the operation, \
                               without modifying the original"]
                 #[inline]
@@ -482,14 +481,13 @@ macro_rules! nonzero_unsigned_operations {
                 /// # Examples
                 ///
                 /// ```
-                /// #![feature(int_log)]
                 #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
-                ///
                 #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(99).unwrap().ilog10(), 1);")]
                 #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(100).unwrap().ilog10(), 2);")]
                 #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(101).unwrap().ilog10(), 2);")]
                 /// ```
-                #[unstable(feature = "int_log", issue = "70887")]
+                #[stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
+                #[rustc_const_stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
                 #[must_use = "this returns the result of the operation, \
                               without modifying the original"]
                 #[inline]
@@ -523,7 +521,6 @@ macro_rules! nonzero_signed_operations {
                 ///
                 /// ```
                 #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
-                ///
                 /// # fn main() { test().unwrap(); }
                 /// # fn test() -> Option<()> {
                 #[doc = concat!("let pos = ", stringify!($Ty), "::new(1)?;")]
@@ -553,7 +550,6 @@ macro_rules! nonzero_signed_operations {
                 ///
                 /// ```
                 #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
-                ///
                 /// # fn main() { test().unwrap(); }
                 /// # fn test() -> Option<()> {
                 #[doc = concat!("let pos = ", stringify!($Ty), "::new(1)?;")]
@@ -588,7 +584,6 @@ macro_rules! nonzero_signed_operations {
                 ///
                 /// ```
                 #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
-                ///
                 /// # fn main() { test().unwrap(); }
                 /// # fn test() -> Option<()> {
                 #[doc = concat!("let pos = ", stringify!($Ty), "::new(1)?;")]
@@ -623,7 +618,6 @@ macro_rules! nonzero_signed_operations {
                 ///
                 /// ```
                 #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
-                ///
                 /// # fn main() { test().unwrap(); }
                 /// # fn test() -> Option<()> {
                 #[doc = concat!("let pos = ", stringify!($Ty), "::new(1)?;")]
@@ -659,7 +653,6 @@ macro_rules! nonzero_signed_operations {
                 ///
                 /// ```
                 #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
-                ///
                 /// # fn main() { test().unwrap(); }
                 /// # fn test() -> Option<()> {
                 #[doc = concat!("let pos = ", stringify!($Ty), "::new(1)?;")]
@@ -902,7 +895,6 @@ macro_rules! nonzero_unsigned_signed_operations {
                 ///
                 /// ```
                 #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
-                ///
                 /// # fn main() { test().unwrap(); }
                 /// # fn test() -> Option<()> {
                 #[doc = concat!("let two = ", stringify!($Ty), "::new(2)?;")]
@@ -938,7 +930,6 @@ macro_rules! nonzero_unsigned_signed_operations {
                 ///
                 /// ```
                 #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
-                ///
                 /// # fn main() { test().unwrap(); }
                 /// # fn test() -> Option<()> {
                 #[doc = concat!("let two = ", stringify!($Ty), "::new(2)?;")]
@@ -983,8 +974,8 @@ macro_rules! nonzero_unsigned_signed_operations {
                 ///
                 /// ```
                 /// #![feature(nonzero_ops)]
-                #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
                 ///
+                #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
                 /// # fn main() { test().unwrap(); }
                 /// # fn test() -> Option<()> {
                 #[doc = concat!("let two = ", stringify!($Ty), "::new(2)?;")]
@@ -1011,7 +1002,6 @@ macro_rules! nonzero_unsigned_signed_operations {
                 ///
                 /// ```
                 #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
-                ///
                 /// # fn main() { test().unwrap(); }
                 /// # fn test() -> Option<()> {
                 #[doc = concat!("let three = ", stringify!($Ty), "::new(3)?;")]
@@ -1055,7 +1045,6 @@ macro_rules! nonzero_unsigned_signed_operations {
                 ///
                 /// ```
                 #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
-                ///
                 /// # fn main() { test().unwrap(); }
                 /// # fn test() -> Option<()> {
                 #[doc = concat!("let three = ", stringify!($Ty), "::new(3)?;")]
@@ -1159,8 +1148,8 @@ macro_rules! nonzero_min_max_unsigned {
                 ///
                 /// ```
                 /// #![feature(nonzero_min_max)]
-                #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
                 ///
+                #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
                 #[doc = concat!("assert_eq!(", stringify!($Ty), "::MIN.get(), 1", stringify!($Int), ");")]
                 /// ```
                 #[unstable(feature = "nonzero_min_max", issue = "89065")]
@@ -1174,8 +1163,8 @@ macro_rules! nonzero_min_max_unsigned {
                 ///
                 /// ```
                 /// #![feature(nonzero_min_max)]
-                #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
                 ///
+                #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
                 #[doc = concat!("assert_eq!(", stringify!($Ty), "::MAX.get(), ", stringify!($Int), "::MAX);")]
                 /// ```
                 #[unstable(feature = "nonzero_min_max", issue = "89065")]
@@ -1201,8 +1190,8 @@ macro_rules! nonzero_min_max_signed {
                 ///
                 /// ```
                 /// #![feature(nonzero_min_max)]
-                #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
                 ///
+                #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
                 #[doc = concat!("assert_eq!(", stringify!($Ty), "::MIN.get(), ", stringify!($Int), "::MIN);")]
                 /// ```
                 #[unstable(feature = "nonzero_min_max", issue = "89065")]
@@ -1220,8 +1209,8 @@ macro_rules! nonzero_min_max_signed {
                 ///
                 /// ```
                 /// #![feature(nonzero_min_max)]
-                #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
                 ///
+                #[doc = concat!("# use std::num::", stringify!($Ty), ";")]
                 #[doc = concat!("assert_eq!(", stringify!($Ty), "::MAX.get(), ", stringify!($Int), "::MAX);")]
                 /// ```
                 #[unstable(feature = "nonzero_min_max", issue = "89065")]
diff --git a/library/core/src/num/uint_macros.rs b/library/core/src/num/uint_macros.rs
index 93f65c5c7aaf..741d7ec6f592 100644
--- a/library/core/src/num/uint_macros.rs
+++ b/library/core/src/num/uint_macros.rs
@@ -109,6 +109,9 @@ macro_rules! uint_impl {
 
         /// Returns the number of leading zeros in the binary representation of `self`.
         ///
+        /// Depending on what you're doing with the value, you might also be interested in the
+        /// [`ilog2`] function which returns a consistent number, even if the type widens.
+        ///
         /// # Examples
         ///
         /// Basic usage:
@@ -118,6 +121,7 @@ macro_rules! uint_impl {
         ///
         /// assert_eq!(n.leading_zeros(), 2);
         /// ```
+        #[doc = concat!("[`ilog2`]: ", stringify!($SelfT), "::ilog2")]
         #[stable(feature = "rust1", since = "1.0.0")]
         #[rustc_const_stable(feature = "const_math", since = "1.32.0")]
         #[must_use = "this returns the result of the operation, \
@@ -478,8 +482,8 @@ macro_rules! uint_impl {
         #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_add_signed(-2), None);")]
         #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).checked_add_signed(3), None);")]
         /// ```
-        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
-        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -692,15 +696,16 @@ macro_rules! uint_impl {
         ///
         /// # Panics
         ///
-        /// This function will panic if `self` is zero, or if `base` is less then 2.
+        /// This function will panic if `self` is zero, or if `base` is less than 2.
         ///
         /// # Examples
         ///
         /// ```
-        /// #![feature(int_log)]
         #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".ilog(5), 1);")]
         /// ```
-        #[unstable(feature = "int_log", issue = "70887")]
+        #[stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_allow_const_fn_unstable(const_option)]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -719,10 +724,11 @@ macro_rules! uint_impl {
         /// # Examples
         ///
         /// ```
-        /// #![feature(int_log)]
         #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".ilog2(), 1);")]
         /// ```
-        #[unstable(feature = "int_log", issue = "70887")]
+        #[stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_allow_const_fn_unstable(const_option)]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -740,10 +746,11 @@ macro_rules! uint_impl {
         /// # Example
         ///
         /// ```
-        /// #![feature(int_log)]
         #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".ilog10(), 1);")]
         /// ```
-        #[unstable(feature = "int_log", issue = "70887")]
+        #[stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_allow_const_fn_unstable(const_option)]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -764,10 +771,10 @@ macro_rules! uint_impl {
         /// # Examples
         ///
         /// ```
-        /// #![feature(int_log)]
         #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_ilog(5), Some(1));")]
         /// ```
-        #[unstable(feature = "int_log", issue = "70887")]
+        #[stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -800,10 +807,10 @@ macro_rules! uint_impl {
         /// # Examples
         ///
         /// ```
-        /// #![feature(int_log)]
         #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".checked_ilog2(), Some(1));")]
         /// ```
-        #[unstable(feature = "int_log", issue = "70887")]
+        #[stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -822,10 +829,10 @@ macro_rules! uint_impl {
         /// # Examples
         ///
         /// ```
-        /// #![feature(int_log)]
         #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".checked_ilog10(), Some(1));")]
         /// ```
-        #[unstable(feature = "int_log", issue = "70887")]
+        #[stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "int_log", since = "CURRENT_RUSTC_VERSION")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -1025,8 +1032,8 @@ macro_rules! uint_impl {
         #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".saturating_add_signed(-2), 0);")]
         #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).saturating_add_signed(4), ", stringify!($SelfT), "::MAX);")]
         /// ```
-        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
-        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -1165,8 +1172,8 @@ macro_rules! uint_impl {
         #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".wrapping_add_signed(-2), ", stringify!($SelfT), "::MAX);")]
         #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).wrapping_add_signed(4), 1);")]
         /// ```
-        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
-        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -1534,8 +1541,8 @@ macro_rules! uint_impl {
         #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".overflowing_add_signed(-2), (", stringify!($SelfT), "::MAX, true));")]
         #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).overflowing_add_signed(4), (1, true));")]
         /// ```
-        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
-        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[stable(feature = "mixed_integer_ops", since = "1.66.0")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
diff --git a/library/core/src/ops/control_flow.rs b/library/core/src/ops/control_flow.rs
index 72ebe653caff..cd183540cd5e 100644
--- a/library/core/src/ops/control_flow.rs
+++ b/library/core/src/ops/control_flow.rs
@@ -79,7 +79,9 @@ use crate::{convert, ops};
 /// [`Break`]: ControlFlow::Break
 /// [`Continue`]: ControlFlow::Continue
 #[stable(feature = "control_flow_enum_type", since = "1.55.0")]
-#[derive(Debug, Clone, Copy, PartialEq)]
+// ControlFlow should not implement PartialOrd or Ord, per RFC 3058:
+// https://rust-lang.github.io/rfcs/3058-try-trait-v2.html#traits-for-controlflow
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub enum ControlFlow<B, C = ()> {
     /// Move on to the next phase of the operation as normal.
     #[stable(feature = "control_flow_enum_type", since = "1.55.0")]
diff --git a/library/core/src/ops/deref.rs b/library/core/src/ops/deref.rs
index 4f4c99c4ad97..c67867f4436e 100644
--- a/library/core/src/ops/deref.rs
+++ b/library/core/src/ops/deref.rs
@@ -61,7 +61,7 @@
 #[doc(alias = "&*")]
 #[stable(feature = "rust1", since = "1.0.0")]
 #[rustc_diagnostic_item = "Deref"]
-#[cfg_attr(not(bootstrap), const_trait)]
+#[const_trait]
 pub trait Deref {
     /// The resulting type after dereferencing.
     #[stable(feature = "rust1", since = "1.0.0")]
diff --git a/library/core/src/ops/function.rs b/library/core/src/ops/function.rs
index 2e0a752c815d..127b047db919 100644
--- a/library/core/src/ops/function.rs
+++ b/library/core/src/ops/function.rs
@@ -1,3 +1,6 @@
+#[cfg(not(bootstrap))]
+use crate::marker::Tuple;
+
 /// The version of the call operator that takes an immutable receiver.
 ///
 /// Instances of `Fn` can be called repeatedly without mutating state.
@@ -51,9 +54,9 @@
 /// let double = |x| x * 2;
 /// assert_eq!(call_with_one(double), 2);
 /// ```
+#[cfg(bootstrap)]
 #[lang = "fn"]
 #[stable(feature = "rust1", since = "1.0.0")]
-#[rustc_diagnostic_item = "Fn"]
 #[rustc_paren_sugar]
 #[rustc_on_unimplemented(
     on(
@@ -71,13 +74,93 @@
 )]
 #[fundamental] // so that regex can rely that `&str: !FnMut`
 #[must_use = "closures are lazy and do nothing unless called"]
-#[cfg_attr(not(bootstrap), const_trait)]
+#[const_trait]
 pub trait Fn<Args>: FnMut<Args> {
     /// Performs the call operation.
     #[unstable(feature = "fn_traits", issue = "29625")]
     extern "rust-call" fn call(&self, args: Args) -> Self::Output;
 }
 
+/// The version of the call operator that takes an immutable receiver.
+///
+/// Instances of `Fn` can be called repeatedly without mutating state.
+///
+/// *This trait (`Fn`) is not to be confused with [function pointers]
+/// (`fn`).*
+///
+/// `Fn` is implemented automatically by closures which only take immutable
+/// references to captured variables or don't capture anything at all, as well
+/// as (safe) [function pointers] (with some caveats, see their documentation
+/// for more details). Additionally, for any type `F` that implements `Fn`, `&F`
+/// implements `Fn`, too.
+///
+/// Since both [`FnMut`] and [`FnOnce`] are supertraits of `Fn`, any
+/// instance of `Fn` can be used as a parameter where a [`FnMut`] or [`FnOnce`]
+/// is expected.
+///
+/// Use `Fn` as a bound when you want to accept a parameter of function-like
+/// type and need to call it repeatedly and without mutating state (e.g., when
+/// calling it concurrently). If you do not need such strict requirements, use
+/// [`FnMut`] or [`FnOnce`] as bounds.
+///
+/// See the [chapter on closures in *The Rust Programming Language*][book] for
+/// some more information on this topic.
+///
+/// Also of note is the special syntax for `Fn` traits (e.g.
+/// `Fn(usize, bool) -> usize`). Those interested in the technical details of
+/// this can refer to [the relevant section in the *Rustonomicon*][nomicon].
+///
+/// [book]: ../../book/ch13-01-closures.html
+/// [function pointers]: fn
+/// [nomicon]: ../../nomicon/hrtb.html
+///
+/// # Examples
+///
+/// ## Calling a closure
+///
+/// ```
+/// let square = |x| x * x;
+/// assert_eq!(square(5), 25);
+/// ```
+///
+/// ## Using a `Fn` parameter
+///
+/// ```
+/// fn call_with_one<F>(func: F) -> usize
+///     where F: Fn(usize) -> usize {
+///     func(1)
+/// }
+///
+/// let double = |x| x * 2;
+/// assert_eq!(call_with_one(double), 2);
+/// ```
+#[cfg(not(bootstrap))]
+#[lang = "fn"]
+#[stable(feature = "rust1", since = "1.0.0")]
+#[rustc_paren_sugar]
+#[rustc_on_unimplemented(
+    on(
+        Args = "()",
+        note = "wrap the `{Self}` in a closure with no arguments: `|| {{ /* code */ }}`"
+    ),
+    on(
+        _Self = "unsafe fn",
+        note = "unsafe function cannot be called generically without an unsafe block",
+        // SAFETY: tidy is not smart enough to tell that the below unsafe block is a string
+        label = "call the function in a closure: `|| unsafe {{ /* code */ }}`"
+    ),
+    message = "expected a `{Fn}<{Args}>` closure, found `{Self}`",
+    label = "expected an `Fn<{Args}>` closure, found `{Self}`"
+)]
+#[fundamental] // so that regex can rely that `&str: !FnMut`
+#[must_use = "closures are lazy and do nothing unless called"]
+#[const_trait]
+pub trait Fn<Args: Tuple>: FnMut<Args> {
+    /// Performs the call operation.
+    #[unstable(feature = "fn_traits", issue = "29625")]
+    extern "rust-call" fn call(&self, args: Args) -> Self::Output;
+}
+
 /// The version of the call operator that takes a mutable receiver.
 ///
 /// Instances of `FnMut` can be called repeatedly and may mutate state.
@@ -139,9 +222,9 @@ pub trait Fn<Args>: FnMut<Args> {
 ///
 /// assert_eq!(x, 5);
 /// ```
+#[cfg(bootstrap)]
 #[lang = "fn_mut"]
 #[stable(feature = "rust1", since = "1.0.0")]
-#[rustc_diagnostic_item = "FnMut"]
 #[rustc_paren_sugar]
 #[rustc_on_unimplemented(
     on(
@@ -159,13 +242,101 @@ pub trait Fn<Args>: FnMut<Args> {
 )]
 #[fundamental] // so that regex can rely that `&str: !FnMut`
 #[must_use = "closures are lazy and do nothing unless called"]
-#[cfg_attr(not(bootstrap), const_trait)]
+#[const_trait]
 pub trait FnMut<Args>: FnOnce<Args> {
     /// Performs the call operation.
     #[unstable(feature = "fn_traits", issue = "29625")]
     extern "rust-call" fn call_mut(&mut self, args: Args) -> Self::Output;
 }
 
+/// The version of the call operator that takes a mutable receiver.
+///
+/// Instances of `FnMut` can be called repeatedly and may mutate state.
+///
+/// `FnMut` is implemented automatically by closures which take mutable
+/// references to captured variables, as well as all types that implement
+/// [`Fn`], e.g., (safe) [function pointers] (since `FnMut` is a supertrait of
+/// [`Fn`]). Additionally, for any type `F` that implements `FnMut`, `&mut F`
+/// implements `FnMut`, too.
+///
+/// Since [`FnOnce`] is a supertrait of `FnMut`, any instance of `FnMut` can be
+/// used where a [`FnOnce`] is expected, and since [`Fn`] is a subtrait of
+/// `FnMut`, any instance of [`Fn`] can be used where `FnMut` is expected.
+///
+/// Use `FnMut` as a bound when you want to accept a parameter of function-like
+/// type and need to call it repeatedly, while allowing it to mutate state.
+/// If you don't want the parameter to mutate state, use [`Fn`] as a
+/// bound; if you don't need to call it repeatedly, use [`FnOnce`].
+///
+/// See the [chapter on closures in *The Rust Programming Language*][book] for
+/// some more information on this topic.
+///
+/// Also of note is the special syntax for `Fn` traits (e.g.
+/// `Fn(usize, bool) -> usize`). Those interested in the technical details of
+/// this can refer to [the relevant section in the *Rustonomicon*][nomicon].
+///
+/// [book]: ../../book/ch13-01-closures.html
+/// [function pointers]: fn
+/// [nomicon]: ../../nomicon/hrtb.html
+///
+/// # Examples
+///
+/// ## Calling a mutably capturing closure
+///
+/// ```
+/// let mut x = 5;
+/// {
+///     let mut square_x = || x *= x;
+///     square_x();
+/// }
+/// assert_eq!(x, 25);
+/// ```
+///
+/// ## Using a `FnMut` parameter
+///
+/// ```
+/// fn do_twice<F>(mut func: F)
+///     where F: FnMut()
+/// {
+///     func();
+///     func();
+/// }
+///
+/// let mut x: usize = 1;
+/// {
+///     let add_two_to_x = || x += 2;
+///     do_twice(add_two_to_x);
+/// }
+///
+/// assert_eq!(x, 5);
+/// ```
+#[cfg(not(bootstrap))]
+#[lang = "fn_mut"]
+#[stable(feature = "rust1", since = "1.0.0")]
+#[rustc_paren_sugar]
+#[rustc_on_unimplemented(
+    on(
+        Args = "()",
+        note = "wrap the `{Self}` in a closure with no arguments: `|| {{ /* code */ }}`"
+    ),
+    on(
+        _Self = "unsafe fn",
+        note = "unsafe function cannot be called generically without an unsafe block",
+        // SAFETY: tidy is not smart enough to tell that the below unsafe block is a string
+        label = "call the function in a closure: `|| unsafe {{ /* code */ }}`"
+    ),
+    message = "expected a `{FnMut}<{Args}>` closure, found `{Self}`",
+    label = "expected an `FnMut<{Args}>` closure, found `{Self}`"
+)]
+#[fundamental] // so that regex can rely that `&str: !FnMut`
+#[must_use = "closures are lazy and do nothing unless called"]
+#[const_trait]
+pub trait FnMut<Args: Tuple>: FnOnce<Args> {
+    /// Performs the call operation.
+    #[unstable(feature = "fn_traits", issue = "29625")]
+    extern "rust-call" fn call_mut(&mut self, args: Args) -> Self::Output;
+}
+
 /// The version of the call operator that takes a by-value receiver.
 ///
 /// Instances of `FnOnce` can be called, but might not be callable multiple
@@ -219,9 +390,9 @@ pub trait FnMut<Args>: FnOnce<Args> {
 ///
 /// // `consume_and_return_x` can no longer be invoked at this point
 /// ```
+#[cfg(bootstrap)]
 #[lang = "fn_once"]
 #[stable(feature = "rust1", since = "1.0.0")]
-#[rustc_diagnostic_item = "FnOnce"]
 #[rustc_paren_sugar]
 #[rustc_on_unimplemented(
     on(
@@ -239,7 +410,7 @@ pub trait FnMut<Args>: FnOnce<Args> {
 )]
 #[fundamental] // so that regex can rely that `&str: !FnMut`
 #[must_use = "closures are lazy and do nothing unless called"]
-#[cfg_attr(not(bootstrap), const_trait)]
+#[const_trait]
 pub trait FnOnce<Args> {
     /// The returned type after the call operator is used.
     #[lang = "fn_once_output"]
@@ -251,6 +422,92 @@ pub trait FnOnce<Args> {
     extern "rust-call" fn call_once(self, args: Args) -> Self::Output;
 }
 
+/// The version of the call operator that takes a by-value receiver.
+///
+/// Instances of `FnOnce` can be called, but might not be callable multiple
+/// times. Because of this, if the only thing known about a type is that it
+/// implements `FnOnce`, it can only be called once.
+///
+/// `FnOnce` is implemented automatically by closures that might consume captured
+/// variables, as well as all types that implement [`FnMut`], e.g., (safe)
+/// [function pointers] (since `FnOnce` is a supertrait of [`FnMut`]).
+///
+/// Since both [`Fn`] and [`FnMut`] are subtraits of `FnOnce`, any instance of
+/// [`Fn`] or [`FnMut`] can be used where a `FnOnce` is expected.
+///
+/// Use `FnOnce` as a bound when you want to accept a parameter of function-like
+/// type and only need to call it once. If you need to call the parameter
+/// repeatedly, use [`FnMut`] as a bound; if you also need it to not mutate
+/// state, use [`Fn`].
+///
+/// See the [chapter on closures in *The Rust Programming Language*][book] for
+/// some more information on this topic.
+///
+/// Also of note is the special syntax for `Fn` traits (e.g.
+/// `Fn(usize, bool) -> usize`). Those interested in the technical details of
+/// this can refer to [the relevant section in the *Rustonomicon*][nomicon].
+///
+/// [book]: ../../book/ch13-01-closures.html
+/// [function pointers]: fn
+/// [nomicon]: ../../nomicon/hrtb.html
+///
+/// # Examples
+///
+/// ## Using a `FnOnce` parameter
+///
+/// ```
+/// fn consume_with_relish<F>(func: F)
+///     where F: FnOnce() -> String
+/// {
+///     // `func` consumes its captured variables, so it cannot be run more
+///     // than once.
+///     println!("Consumed: {}", func());
+///
+///     println!("Delicious!");
+///
+///     // Attempting to invoke `func()` again will throw a `use of moved
+///     // value` error for `func`.
+/// }
+///
+/// let x = String::from("x");
+/// let consume_and_return_x = move || x;
+/// consume_with_relish(consume_and_return_x);
+///
+/// // `consume_and_return_x` can no longer be invoked at this point
+/// ```
+#[cfg(not(bootstrap))]
+#[lang = "fn_once"]
+#[stable(feature = "rust1", since = "1.0.0")]
+#[rustc_paren_sugar]
+#[rustc_on_unimplemented(
+    on(
+        Args = "()",
+        note = "wrap the `{Self}` in a closure with no arguments: `|| {{ /* code */ }}`"
+    ),
+    on(
+        _Self = "unsafe fn",
+        note = "unsafe function cannot be called generically without an unsafe block",
+        // SAFETY: tidy is not smart enough to tell that the below unsafe block is a string
+        label = "call the function in a closure: `|| unsafe {{ /* code */ }}`"
+    ),
+    message = "expected a `{FnOnce}<{Args}>` closure, found `{Self}`",
+    label = "expected an `FnOnce<{Args}>` closure, found `{Self}`"
+)]
+#[fundamental] // so that regex can rely that `&str: !FnMut`
+#[must_use = "closures are lazy and do nothing unless called"]
+#[const_trait]
+pub trait FnOnce<Args: Tuple> {
+    /// The returned type after the call operator is used.
+    #[lang = "fn_once_output"]
+    #[stable(feature = "fn_once_output", since = "1.12.0")]
+    type Output;
+
+    /// Performs the call operation.
+    #[unstable(feature = "fn_traits", issue = "29625")]
+    extern "rust-call" fn call_once(self, args: Args) -> Self::Output;
+}
+
+#[cfg(bootstrap)]
 mod impls {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_const_unstable(feature = "const_fn_trait_ref_impls", issue = "101803")]
@@ -310,3 +567,66 @@ mod impls {
         }
     }
 }
+
+#[cfg(not(bootstrap))]
+mod impls {
+    use crate::marker::Tuple;
+
+    #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_unstable(feature = "const_fn_trait_ref_impls", issue = "101803")]
+    impl<A: Tuple, F: ?Sized> const Fn<A> for &F
+    where
+        F: ~const Fn<A>,
+    {
+        extern "rust-call" fn call(&self, args: A) -> F::Output {
+            (**self).call(args)
+        }
+    }
+
+    #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_unstable(feature = "const_fn_trait_ref_impls", issue = "101803")]
+    impl<A: Tuple, F: ?Sized> const FnMut<A> for &F
+    where
+        F: ~const Fn<A>,
+    {
+        extern "rust-call" fn call_mut(&mut self, args: A) -> F::Output {
+            (**self).call(args)
+        }
+    }
+
+    #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_unstable(feature = "const_fn_trait_ref_impls", issue = "101803")]
+    impl<A: Tuple, F: ?Sized> const FnOnce<A> for &F
+    where
+        F: ~const Fn<A>,
+    {
+        type Output = F::Output;
+
+        extern "rust-call" fn call_once(self, args: A) -> F::Output {
+            (*self).call(args)
+        }
+    }
+
+    #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_unstable(feature = "const_fn_trait_ref_impls", issue = "101803")]
+    impl<A: Tuple, F: ?Sized> const FnMut<A> for &mut F
+    where
+        F: ~const FnMut<A>,
+    {
+        extern "rust-call" fn call_mut(&mut self, args: A) -> F::Output {
+            (*self).call_mut(args)
+        }
+    }
+
+    #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_unstable(feature = "const_fn_trait_ref_impls", issue = "101803")]
+    impl<A: Tuple, F: ?Sized> const FnOnce<A> for &mut F
+    where
+        F: ~const FnMut<A>,
+    {
+        type Output = F::Output;
+        extern "rust-call" fn call_once(self, args: A) -> F::Output {
+            (*self).call_mut(args)
+        }
+    }
+}
diff --git a/library/core/src/ops/index.rs b/library/core/src/ops/index.rs
index dd4e3ac1c2fe..5e3dc48b6ca1 100644
--- a/library/core/src/ops/index.rs
+++ b/library/core/src/ops/index.rs
@@ -55,7 +55,7 @@
 #[doc(alias = "]")]
 #[doc(alias = "[")]
 #[doc(alias = "[]")]
-#[cfg_attr(not(bootstrap), const_trait)]
+#[const_trait]
 pub trait Index<Idx: ?Sized> {
     /// The returned type after indexing.
     #[stable(feature = "rust1", since = "1.0.0")]
@@ -164,7 +164,7 @@ see chapter in The Book <https://doc.rust-lang.org/book/ch08-02-strings.html#ind
 #[doc(alias = "[")]
 #[doc(alias = "]")]
 #[doc(alias = "[]")]
-#[cfg_attr(not(bootstrap), const_trait)]
+#[const_trait]
 pub trait IndexMut<Idx: ?Sized>: Index<Idx> {
     /// Performs the mutable indexing (`container[index]`) operation.
     ///
diff --git a/library/core/src/ops/index_range.rs b/library/core/src/ops/index_range.rs
index 41ffe11f610d..3e06776d2c6f 100644
--- a/library/core/src/ops/index_range.rs
+++ b/library/core/src/ops/index_range.rs
@@ -19,7 +19,12 @@ impl IndexRange {
     #[inline]
     pub const unsafe fn new_unchecked(start: usize, end: usize) -> Self {
         // SAFETY: comparisons on usize are pure
-        unsafe { assert_unsafe_precondition!((start: usize, end: usize) => start <= end) };
+        unsafe {
+            assert_unsafe_precondition!(
+               "IndexRange::new_unchecked requires `start <= end`",
+                (start: usize, end: usize) => start <= end
+            )
+        };
         IndexRange { start, end }
     }
 
diff --git a/library/core/src/option.rs b/library/core/src/option.rs
index 4b57371096e9..f284b4359557 100644
--- a/library/core/src/option.rs
+++ b/library/core/src/option.rs
@@ -1713,8 +1713,6 @@ impl<T, U> Option<(T, U)> {
     /// # Examples
     ///
     /// ```
-    /// #![feature(unzip_option)]
-    ///
     /// let x = Some((1, "hi"));
     /// let y = None::<(u8, u32)>;
     ///
@@ -1722,8 +1720,13 @@ impl<T, U> Option<(T, U)> {
     /// assert_eq!(y.unzip(), (None, None));
     /// ```
     #[inline]
-    #[unstable(feature = "unzip_option", issue = "87800", reason = "recently added")]
-    pub const fn unzip(self) -> (Option<T>, Option<U>) {
+    #[stable(feature = "unzip_option", since = "1.66.0")]
+    #[rustc_const_unstable(feature = "const_option", issue = "67441")]
+    pub const fn unzip(self) -> (Option<T>, Option<U>)
+    where
+        T: ~const Destruct,
+        U: ~const Destruct,
+    {
         match self {
             Some((a, b)) => (Some(a), Some(b)),
             None => (None, None),
diff --git a/library/core/src/panic.rs b/library/core/src/panic.rs
index 00b63dfbd069..461b70c32f36 100644
--- a/library/core/src/panic.rs
+++ b/library/core/src/panic.rs
@@ -80,7 +80,6 @@ pub macro unreachable_2015 {
 #[doc(hidden)]
 #[unstable(feature = "edition_panic", issue = "none", reason = "use unreachable!() instead")]
 #[allow_internal_unstable(core_panic)]
-#[rustc_diagnostic_item = "unreachable_2021_macro"]
 #[rustc_macro_transparency = "semitransparent"]
 pub macro unreachable_2021 {
     () => (
diff --git a/library/core/src/panicking.rs b/library/core/src/panicking.rs
index a9de7c94e5a1..4fd1eb234137 100644
--- a/library/core/src/panicking.rs
+++ b/library/core/src/panicking.rs
@@ -70,8 +70,7 @@ pub const fn panic_fmt(fmt: fmt::Arguments<'_>) -> ! {
 #[cold]
 #[cfg_attr(not(feature = "panic_immediate_abort"), inline(never))]
 #[cfg_attr(feature = "panic_immediate_abort", inline)]
-#[cfg_attr(not(bootstrap), rustc_nounwind)]
-#[cfg_attr(bootstrap, rustc_allocator_nounwind)]
+#[rustc_nounwind]
 pub fn panic_str_nounwind(msg: &'static str) -> ! {
     if cfg!(feature = "panic_immediate_abort") {
         super::intrinsics::abort()
@@ -158,8 +157,7 @@ fn panic_bounds_check(index: usize, len: usize) -> ! {
 #[cold]
 #[inline(never)]
 #[lang = "panic_no_unwind"] // needed by codegen for panic in nounwind function
-#[cfg_attr(not(bootstrap), rustc_nounwind)]
-#[cfg_attr(bootstrap, rustc_allocator_nounwind)]
+#[rustc_nounwind]
 fn panic_no_unwind() -> ! {
     panic_str_nounwind("panic in a function that cannot unwind")
 }
diff --git a/library/core/src/pin.rs b/library/core/src/pin.rs
index ccef35b45325..f0258640e2ae 100644
--- a/library/core/src/pin.rs
+++ b/library/core/src/pin.rs
@@ -1059,7 +1059,7 @@ impl<P, U> DispatchFromDyn<Pin<U>> for Pin<P> where P: DispatchFromDyn<U> {}
 /// 8  | let x: Pin<&mut Foo> = {
 ///    |     - borrow later stored here
 /// 9  |     let x: Pin<&mut Foo> = pin!(Foo { /* … */ });
-///    |                            ^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+///    |                            ^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
 /// 10 |     x
 /// 11 | }; // <- Foo is dropped
 ///    | - temporary value is freed at the end of this statement
diff --git a/library/core/src/prelude/v1.rs b/library/core/src/prelude/v1.rs
index b566e211cd89..d3d255a802d7 100644
--- a/library/core/src/prelude/v1.rs
+++ b/library/core/src/prelude/v1.rs
@@ -75,9 +75,16 @@ pub use crate::macros::builtin::{RustcDecodable, RustcEncodable};
 
 // Do not `doc(no_inline)` so that they become doc items on their own
 // (no public module for them to be re-exported from).
+#[cfg(not(bootstrap))]
+#[stable(feature = "builtin_macro_prelude", since = "1.38.0")]
+pub use crate::macros::builtin::alloc_error_handler;
 #[stable(feature = "builtin_macro_prelude", since = "1.38.0")]
 pub use crate::macros::builtin::{bench, derive, global_allocator, test, test_case};
 
+#[unstable(feature = "derive_const", issue = "none")]
+#[cfg(not(bootstrap))]
+pub use crate::macros::builtin::derive_const;
+
 #[unstable(
     feature = "cfg_accessible",
     issue = "64797",
diff --git a/library/core/src/ptr/alignment.rs b/library/core/src/ptr/alignment.rs
index 846efbc4ebf6..1390e09dd96a 100644
--- a/library/core/src/ptr/alignment.rs
+++ b/library/core/src/ptr/alignment.rs
@@ -76,7 +76,12 @@ impl Alignment {
     #[inline]
     pub const unsafe fn new_unchecked(align: usize) -> Self {
         // SAFETY: Precondition passed to the caller.
-        unsafe { assert_unsafe_precondition!((align: usize) => align.is_power_of_two()) };
+        unsafe {
+            assert_unsafe_precondition!(
+               "Alignment::new_unchecked requires a power of two",
+                (align: usize) => align.is_power_of_two()
+            )
+        };
 
         // SAFETY: By precondition, this must be a power of two, and
         // our variants encompass all possible powers of two.
diff --git a/library/core/src/ptr/const_ptr.rs b/library/core/src/ptr/const_ptr.rs
index 67e59460d74b..926d2ae51139 100644
--- a/library/core/src/ptr/const_ptr.rs
+++ b/library/core/src/ptr/const_ptr.rs
@@ -568,6 +568,31 @@ impl<T: ?Sized> *const T {
     ///
     /// For non-`Sized` pointees this operation changes only the data pointer,
     /// leaving the metadata untouched.
+    ///
+    /// ## Examples
+    ///
+    /// ```
+    /// #![feature(ptr_mask, strict_provenance)]
+    /// let v = 17_u32;
+    /// let ptr: *const u32 = &v;
+    ///
+    /// // `u32` is 4 bytes aligned,
+    /// // which means that lower 2 bits are always 0.
+    /// let tag_mask = 0b11;
+    /// let ptr_mask = !tag_mask;
+    ///
+    /// // We can store something in these lower bits
+    /// let tagged_ptr = ptr.map_addr(|a| a | 0b10);
+    ///
+    /// // Get the "tag" back
+    /// let tag = tagged_ptr.addr() & tag_mask;
+    /// assert_eq!(tag, 0b10);
+    ///
+    /// // Note that `tagged_ptr` is unaligned, it's UB to read from it.
+    /// // To get original pointer `mask` can be used:
+    /// let masked_ptr = tagged_ptr.mask(ptr_mask);
+    /// assert_eq!(unsafe { *masked_ptr }, 17);
+    /// ```
     #[unstable(feature = "ptr_mask", issue = "98290")]
     #[must_use = "returns a new pointer rather than modifying its argument"]
     #[inline(always)]
@@ -761,7 +786,10 @@ impl<T: ?Sized> *const T {
         // SAFETY: The comparison has no side-effects, and the intrinsic
         // does this check internally in the CTFE implementation.
         unsafe {
-            assert_unsafe_precondition!([T](this: *const T, origin: *const T) => this >= origin)
+            assert_unsafe_precondition!(
+                "ptr::sub_ptr requires `this >= origin`",
+                [T](this: *const T, origin: *const T) => this >= origin
+            )
         };
 
         let pointee_size = mem::size_of::<T>();
@@ -802,7 +830,7 @@ impl<T: ?Sized> *const T {
 
     /// Returns whether two pointers are guaranteed to be inequal.
     ///
-    /// At runtime this function behaves like `Some(self == other)`.
+    /// At runtime this function behaves like `Some(self != other)`.
     /// However, in some contexts (e.g., compile-time evaluation),
     /// it is not always possible to determine inequality of two pointers, so this function may
     /// spuriously return `None` for pointers that later actually turn out to have its inequality known.
diff --git a/library/core/src/ptr/metadata.rs b/library/core/src/ptr/metadata.rs
index caa10f1818b4..a8604843e963 100644
--- a/library/core/src/ptr/metadata.rs
+++ b/library/core/src/ptr/metadata.rs
@@ -50,6 +50,7 @@ use crate::hash::{Hash, Hasher};
 ///
 /// [`to_raw_parts`]: *const::to_raw_parts
 #[lang = "pointee_trait"]
+#[cfg_attr(not(bootstrap), rustc_deny_explicit_impl)]
 pub trait Pointee {
     /// The type for metadata in pointers and references to `Self`.
     #[lang = "metadata_type"]
diff --git a/library/core/src/ptr/mod.rs b/library/core/src/ptr/mod.rs
index cfffe351a87d..742fe4f3f633 100644
--- a/library/core/src/ptr/mod.rs
+++ b/library/core/src/ptr/mod.rs
@@ -35,7 +35,8 @@
 //!   be used for inter-thread synchronization.
 //! * The result of casting a reference to a pointer is valid for as long as the
 //!   underlying object is live and no reference (just raw pointers) is used to
-//!   access the same memory.
+//!   access the same memory. That is, reference and pointer accesses cannot be
+//!   interleaved.
 //!
 //! These axioms, along with careful use of [`offset`] for pointer arithmetic,
 //! are enough to correctly implement many useful things in unsafe code. Stronger guarantees
@@ -64,7 +65,6 @@
 //! separate allocated object), heap allocations (each allocation created by the global allocator is
 //! a separate allocated object), and `static` variables.
 //!
-//!
 //! # Strict Provenance
 //!
 //! **The following text is non-normative, insufficiently formal, and is an extremely strict
@@ -581,12 +581,21 @@ pub const fn invalid_mut<T>(addr: usize) -> *mut T {
 /// Convert an address back to a pointer, picking up a previously 'exposed' provenance.
 ///
 /// This is equivalent to `addr as *const T`. The provenance of the returned pointer is that of *any*
-/// pointer that was previously passed to [`expose_addr`][pointer::expose_addr] or a `ptr as usize`
-/// cast. If there is no previously 'exposed' provenance that justifies the way this pointer will be
-/// used, the program has undefined behavior. Note that there is no algorithm that decides which
-/// provenance will be used. You can think of this as "guessing" the right provenance, and the guess
-/// will be "maximally in your favor", in the sense that if there is any way to avoid undefined
-/// behavior, then that is the guess that will be taken.
+/// pointer that was previously exposed by passing it to [`expose_addr`][pointer::expose_addr],
+/// or a `ptr as usize` cast. In addition, memory which is outside the control of the Rust abstract
+/// machine (MMIO registers, for example) is always considered to be exposed, so long as this memory
+/// is disjoint from memory that will be used by the abstract machine such as the stack, heap,
+/// and statics.
+///
+/// If there is no 'exposed' provenance that justifies the way this pointer will be used,
+/// the program has undefined behavior. In particular, the aliasing rules still apply: pointers
+/// and references that have been invalidated due to aliasing accesses cannot be used any more,
+/// even if they have been exposed!
+///
+/// Note that there is no algorithm that decides which provenance will be used. You can think of this
+/// as "guessing" the right provenance, and the guess will be "maximally in your favor", in the sense
+/// that if there is any way to avoid undefined behavior (while upholding all aliasing requirements),
+/// then that is the guess that will be taken.
 ///
 /// On platforms with multiple address spaces, it is your responsibility to ensure that the
 /// address makes sense in the address space that this pointer will be used with.
@@ -889,7 +898,10 @@ pub const unsafe fn swap_nonoverlapping<T>(x: *mut T, y: *mut T, count: usize) {
     // SAFETY: the caller must guarantee that `x` and `y` are
     // valid for writes and properly aligned.
     unsafe {
-        assert_unsafe_precondition!([T](x: *mut T, y: *mut T, count: usize) =>
+        assert_unsafe_precondition!(
+            "ptr::swap_nonoverlapping requires that both pointer arguments are aligned and non-null \
+            and the specified memory ranges do not overlap",
+            [T](x: *mut T, y: *mut T, count: usize) =>
             is_aligned_and_not_null(x)
                 && is_aligned_and_not_null(y)
                 && is_nonoverlapping(x, y, count)
@@ -986,7 +998,10 @@ pub const unsafe fn replace<T>(dst: *mut T, mut src: T) -> T {
     // and cannot overlap `src` since `dst` must point to a distinct
     // allocated object.
     unsafe {
-        assert_unsafe_precondition!([T](dst: *mut T) => is_aligned_and_not_null(dst));
+        assert_unsafe_precondition!(
+            "ptr::replace requires that the pointer argument is aligned and non-null",
+            [T](dst: *mut T) => is_aligned_and_not_null(dst)
+        );
         mem::swap(&mut *dst, &mut src); // cannot overlap
     }
     src
@@ -1117,7 +1132,10 @@ pub const unsafe fn read<T>(src: *const T) -> T {
     // Also, since we just wrote a valid value into `tmp`, it is guaranteed
     // to be properly initialized.
     unsafe {
-        assert_unsafe_precondition!([T](src: *const T) => is_aligned_and_not_null(src));
+        assert_unsafe_precondition!(
+            "ptr::read requires that the pointer argument is aligned and non-null",
+            [T](src: *const T) => is_aligned_and_not_null(src)
+        );
         copy_nonoverlapping(src, tmp.as_mut_ptr(), 1);
         tmp.assume_init()
     }
@@ -1311,7 +1329,10 @@ pub const unsafe fn write<T>(dst: *mut T, src: T) {
     // `dst` cannot overlap `src` because the caller has mutable access
     // to `dst` while `src` is owned by this function.
     unsafe {
-        assert_unsafe_precondition!([T](dst: *mut T) => is_aligned_and_not_null(dst));
+        assert_unsafe_precondition!(
+            "ptr::write requires that the pointer argument is aligned and non-null",
+            [T](dst: *mut T) => is_aligned_and_not_null(dst)
+        );
         copy_nonoverlapping(&src as *const T, dst, 1);
         intrinsics::forget(src);
     }
@@ -1475,7 +1496,10 @@ pub const unsafe fn write_unaligned<T>(dst: *mut T, src: T) {
 pub unsafe fn read_volatile<T>(src: *const T) -> T {
     // SAFETY: the caller must uphold the safety contract for `volatile_load`.
     unsafe {
-        assert_unsafe_precondition!([T](src: *const T) => is_aligned_and_not_null(src));
+        assert_unsafe_precondition!(
+            "ptr::read_volatile requires that the pointer argument is aligned and non-null",
+            [T](src: *const T) => is_aligned_and_not_null(src)
+        );
         intrinsics::volatile_load(src)
     }
 }
@@ -1546,7 +1570,10 @@ pub unsafe fn read_volatile<T>(src: *const T) -> T {
 pub unsafe fn write_volatile<T>(dst: *mut T, src: T) {
     // SAFETY: the caller must uphold the safety contract for `volatile_store`.
     unsafe {
-        assert_unsafe_precondition!([T](dst: *mut T) => is_aligned_and_not_null(dst));
+        assert_unsafe_precondition!(
+            "ptr::write_volatile requires that the pointer argument is aligned and non-null",
+            [T](dst: *mut T) => is_aligned_and_not_null(dst)
+        );
         intrinsics::volatile_store(dst, src);
     }
 }
@@ -1733,6 +1760,12 @@ pub(crate) unsafe fn align_offset<T: Sized>(p: *const T, a: usize) -> usize {
 /// by their address rather than comparing the values they point to
 /// (which is what the `PartialEq for &T` implementation does).
 ///
+/// When comparing wide pointers, both the address and the metadata are tested for equality.
+/// However, note that comparing trait object pointers (`*const dyn Trait`) is unrealiable: pointers
+/// to values of the same underlying type can compare inequal (because vtables are duplicated in
+/// multiple codegen units), and pointers to values of *different* underlying type can compare equal
+/// (since identical vtables can be deduplicated within a codegen unit).
+///
 /// # Examples
 ///
 /// ```
@@ -1759,41 +1792,6 @@ pub(crate) unsafe fn align_offset<T: Sized>(p: *const T, a: usize) -> usize {
 /// assert!(!std::ptr::eq(&a[..2], &a[..3]));
 /// assert!(!std::ptr::eq(&a[0..2], &a[1..3]));
 /// ```
-///
-/// Traits are also compared by their implementation:
-///
-/// ```
-/// #[repr(transparent)]
-/// struct Wrapper { member: i32 }
-///
-/// trait Trait {}
-/// impl Trait for Wrapper {}
-/// impl Trait for i32 {}
-///
-/// let wrapper = Wrapper { member: 10 };
-///
-/// // Pointers have equal addresses.
-/// assert!(std::ptr::eq(
-///     &wrapper as *const Wrapper as *const u8,
-///     &wrapper.member as *const i32 as *const u8
-/// ));
-///
-/// // Objects have equal addresses, but `Trait` has different implementations.
-/// assert!(!std::ptr::eq(
-///     &wrapper as &dyn Trait,
-///     &wrapper.member as &dyn Trait,
-/// ));
-/// assert!(!std::ptr::eq(
-///     &wrapper as &dyn Trait as *const dyn Trait,
-///     &wrapper.member as &dyn Trait as *const dyn Trait,
-/// ));
-///
-/// // Converting the reference to a `*const u8` compares by address.
-/// assert!(std::ptr::eq(
-///     &wrapper as &dyn Trait as *const dyn Trait as *const u8,
-///     &wrapper.member as &dyn Trait as *const dyn Trait as *const u8,
-/// ));
-/// ```
 #[stable(feature = "ptr_eq", since = "1.17.0")]
 #[inline]
 pub fn eq<T: ?Sized>(a: *const T, b: *const T) -> bool {
@@ -1864,7 +1862,6 @@ macro_rules! fnptr_impls_safety_abi {
         fnptr_impls_safety_abi! { #[stable(feature = "fnptr_impls", since = "1.4.0")] $FnTy, $($Arg),* }
     };
     (@c_unwind $FnTy: ty, $($Arg: ident),*) => {
-        #[cfg(not(bootstrap))]
         fnptr_impls_safety_abi! { #[unstable(feature = "c_unwind", issue = "74990")] $FnTy, $($Arg),* }
     };
     (#[$meta:meta] $FnTy: ty, $($Arg: ident),*) => {
diff --git a/library/core/src/ptr/mut_ptr.rs b/library/core/src/ptr/mut_ptr.rs
index 0bb2566fd4c9..f71696e9ca0f 100644
--- a/library/core/src/ptr/mut_ptr.rs
+++ b/library/core/src/ptr/mut_ptr.rs
@@ -588,6 +588,34 @@ impl<T: ?Sized> *mut T {
     ///
     /// For non-`Sized` pointees this operation changes only the data pointer,
     /// leaving the metadata untouched.
+    ///
+    /// ## Examples
+    ///
+    /// ```
+    /// #![feature(ptr_mask, strict_provenance)]
+    /// let mut v = 17_u32;
+    /// let ptr: *mut u32 = &mut v;
+    ///
+    /// // `u32` is 4 bytes aligned,
+    /// // which means that lower 2 bits are always 0.
+    /// let tag_mask = 0b11;
+    /// let ptr_mask = !tag_mask;
+    ///
+    /// // We can store something in these lower bits
+    /// let tagged_ptr = ptr.map_addr(|a| a | 0b10);
+    ///
+    /// // Get the "tag" back
+    /// let tag = tagged_ptr.addr() & tag_mask;
+    /// assert_eq!(tag, 0b10);
+    ///
+    /// // Note that `tagged_ptr` is unaligned, it's UB to read from/write to it.
+    /// // To get original pointer `mask` can be used:
+    /// let masked_ptr = tagged_ptr.mask(ptr_mask);
+    /// assert_eq!(unsafe { *masked_ptr }, 17);
+    ///
+    /// unsafe { *masked_ptr = 0 };
+    /// assert_eq!(v, 0);
+    /// ```
     #[unstable(feature = "ptr_mask", issue = "98290")]
     #[must_use = "returns a new pointer rather than modifying its argument"]
     #[inline(always)]
@@ -730,7 +758,7 @@ impl<T: ?Sized> *mut T {
 
     /// Returns whether two pointers are guaranteed to be inequal.
     ///
-    /// At runtime this function behaves like `Some(self == other)`.
+    /// At runtime this function behaves like `Some(self != other)`.
     /// However, in some contexts (e.g., compile-time evaluation),
     /// it is not always possible to determine inequality of two pointers, so this function may
     /// spuriously return `None` for pointers that later actually turn out to have its inequality known.
diff --git a/library/core/src/ptr/non_null.rs b/library/core/src/ptr/non_null.rs
index 7264d57ba6ae..c18264d13eba 100644
--- a/library/core/src/ptr/non_null.rs
+++ b/library/core/src/ptr/non_null.rs
@@ -197,7 +197,7 @@ impl<T: ?Sized> NonNull<T> {
     pub const unsafe fn new_unchecked(ptr: *mut T) -> Self {
         // SAFETY: the caller must guarantee that `ptr` is non-null.
         unsafe {
-            assert_unsafe_precondition!([T: ?Sized](ptr: *mut T) => !ptr.is_null());
+            assert_unsafe_precondition!("NonNull::new_unchecked requires that the pointer is non-null", [T: ?Sized](ptr: *mut T) => !ptr.is_null());
             NonNull { pointer: ptr as _ }
         }
     }
diff --git a/library/core/src/slice/index.rs b/library/core/src/slice/index.rs
index 916d0262dedb..6d2f7330d5db 100644
--- a/library/core/src/slice/index.rs
+++ b/library/core/src/slice/index.rs
@@ -232,7 +232,10 @@ unsafe impl<T> const SliceIndex<[T]> for usize {
         // `self` is in bounds of `slice` so `self` cannot overflow an `isize`,
         // so the call to `add` is safe.
         unsafe {
-            assert_unsafe_precondition!([T](this: usize, slice: *const [T]) => this < slice.len());
+            assert_unsafe_precondition!(
+                "slice::get_unchecked requires that the index is within the slice",
+                [T](this: usize, slice: *const [T]) => this < slice.len()
+            );
             slice.as_ptr().add(self)
         }
     }
@@ -242,7 +245,10 @@ unsafe impl<T> const SliceIndex<[T]> for usize {
         let this = self;
         // SAFETY: see comments for `get_unchecked` above.
         unsafe {
-            assert_unsafe_precondition!([T](this: usize, slice: *mut [T]) => this < slice.len());
+            assert_unsafe_precondition!(
+                "slice::get_unchecked_mut requires that the index is within the slice",
+                [T](this: usize, slice: *mut [T]) => this < slice.len()
+            );
             slice.as_mut_ptr().add(self)
         }
     }
@@ -295,8 +301,10 @@ unsafe impl<T> const SliceIndex<[T]> for ops::IndexRange {
         // so the call to `add` is safe.
 
         unsafe {
-            assert_unsafe_precondition!([T](end: usize, slice: *const [T]) =>
-                end <= slice.len());
+            assert_unsafe_precondition!(
+                "slice::get_unchecked requires that the index is within the slice",
+                [T](end: usize, slice: *const [T]) => end <= slice.len()
+            );
             ptr::slice_from_raw_parts(slice.as_ptr().add(self.start()), self.len())
         }
     }
@@ -306,8 +314,10 @@ unsafe impl<T> const SliceIndex<[T]> for ops::IndexRange {
         let end = self.end();
         // SAFETY: see comments for `get_unchecked` above.
         unsafe {
-            assert_unsafe_precondition!([T](end: usize, slice: *mut [T]) =>
-                end <= slice.len());
+            assert_unsafe_precondition!(
+                "slice::get_unchecked_mut requires that the index is within the slice",
+                [T](end: usize, slice: *mut [T]) => end <= slice.len()
+            );
             ptr::slice_from_raw_parts_mut(slice.as_mut_ptr().add(self.start()), self.len())
         }
     }
@@ -367,8 +377,11 @@ unsafe impl<T> const SliceIndex<[T]> for ops::Range<usize> {
         // so the call to `add` is safe.
 
         unsafe {
-            assert_unsafe_precondition!([T](this: ops::Range<usize>, slice: *const [T]) =>
-            this.end >= this.start && this.end <= slice.len());
+            assert_unsafe_precondition!(
+                "slice::get_unchecked requires that the range is within the slice",
+                [T](this: ops::Range<usize>, slice: *const [T]) =>
+                this.end >= this.start && this.end <= slice.len()
+            );
             ptr::slice_from_raw_parts(slice.as_ptr().add(self.start), self.end - self.start)
         }
     }
@@ -378,8 +391,11 @@ unsafe impl<T> const SliceIndex<[T]> for ops::Range<usize> {
         let this = ops::Range { start: self.start, end: self.end };
         // SAFETY: see comments for `get_unchecked` above.
         unsafe {
-            assert_unsafe_precondition!([T](this: ops::Range<usize>, slice: *mut [T]) =>
-                this.end >= this.start && this.end <= slice.len());
+            assert_unsafe_precondition!(
+                "slice::get_unchecked_mut requires that the range is within the slice",
+                [T](this: ops::Range<usize>, slice: *mut [T]) =>
+                this.end >= this.start && this.end <= slice.len()
+            );
             ptr::slice_from_raw_parts_mut(slice.as_mut_ptr().add(self.start), self.end - self.start)
         }
     }
diff --git a/library/core/src/slice/mod.rs b/library/core/src/slice/mod.rs
index 94ab13ed2e04..0f58bc643d96 100644
--- a/library/core/src/slice/mod.rs
+++ b/library/core/src/slice/mod.rs
@@ -653,7 +653,10 @@ impl<T> [T] {
         let ptr = this.as_mut_ptr();
         // SAFETY: caller has to guarantee that `a < self.len()` and `b < self.len()`
         unsafe {
-            assert_unsafe_precondition!([T](a: usize, b: usize, this: &mut [T]) => a < this.len() && b < this.len());
+            assert_unsafe_precondition!(
+                "slice::swap_unchecked requires that the indices are within the slice",
+                [T](a: usize, b: usize, this: &mut [T]) => a < this.len() && b < this.len()
+            );
             ptr::swap(ptr.add(a), ptr.add(b));
         }
     }
@@ -969,7 +972,10 @@ impl<T> [T] {
         let this = self;
         // SAFETY: Caller must guarantee that `N` is nonzero and exactly divides the slice length
         let new_len = unsafe {
-            assert_unsafe_precondition!([T](this: &[T], N: usize) => N != 0 && this.len() % N == 0);
+            assert_unsafe_precondition!(
+                "slice::as_chunks_unchecked requires `N != 0` and the slice to split exactly into `N`-element chunks",
+                [T](this: &[T], N: usize) => N != 0 && this.len() % N == 0
+            );
             exact_div(self.len(), N)
         };
         // SAFETY: We cast a slice of `new_len * N` elements into
@@ -1109,7 +1115,10 @@ impl<T> [T] {
         let this = &*self;
         // SAFETY: Caller must guarantee that `N` is nonzero and exactly divides the slice length
         let new_len = unsafe {
-            assert_unsafe_precondition!([T](this: &[T], N: usize) => N != 0 && this.len() % N == 0);
+            assert_unsafe_precondition!(
+                "slice::as_chunks_unchecked_mut requires `N != 0` and the slice to split exactly into `N`-element chunks",
+                [T](this: &[T], N: usize) => N != 0 && this.len() % N == 0
+            );
             exact_div(this.len(), N)
         };
         // SAFETY: We cast a slice of `new_len * N` elements into
@@ -1685,7 +1694,10 @@ impl<T> [T] {
         // `[ptr; mid]` and `[mid; len]` are not overlapping, so returning a mutable reference
         // is fine.
         unsafe {
-            assert_unsafe_precondition!((mid: usize, len: usize) => mid <= len);
+            assert_unsafe_precondition!(
+                "slice::split_at_mut_unchecked requires the index to be within the slice",
+                (mid: usize, len: usize) => mid <= len
+            );
             (from_raw_parts_mut(ptr, mid), from_raw_parts_mut(ptr.add(mid), len - mid))
         }
     }
@@ -3512,8 +3524,8 @@ impl<T> [T] {
         }
     }
 
-    /// Transmute the slice to a slice of another type, ensuring alignment of the types is
-    /// maintained.
+    /// Transmute the mutable slice to a mutable slice of another type, ensuring alignment of the
+    /// types is maintained.
     ///
     /// This method splits the slice into three distinct slices: prefix, correctly aligned middle
     /// slice of a new type, and the suffix slice. The method may make the middle slice the greatest
@@ -3655,7 +3667,8 @@ impl<T> [T] {
         unsafe { self.align_to() }
     }
 
-    /// Split a slice into a prefix, a middle of aligned SIMD types, and a suffix.
+    /// Split a mutable slice into a mutable prefix, a middle of aligned SIMD types,
+    /// and a mutable suffix.
     ///
     /// This is a safe wrapper around [`slice::align_to_mut`], so has the same weak
     /// postconditions as that method.  You're only assured that
diff --git a/library/core/src/slice/raw.rs b/library/core/src/slice/raw.rs
index 3c5abd215a4b..052fd34d0b6b 100644
--- a/library/core/src/slice/raw.rs
+++ b/library/core/src/slice/raw.rs
@@ -1,7 +1,9 @@
 //! Free functions to create `&[T]` and `&mut [T]`.
 
 use crate::array;
-use crate::intrinsics::{assert_unsafe_precondition, is_aligned_and_not_null};
+use crate::intrinsics::{
+    assert_unsafe_precondition, is_aligned_and_not_null, is_valid_allocation_size,
+};
 use crate::ops::Range;
 use crate::ptr;
 
@@ -90,9 +92,10 @@ use crate::ptr;
 pub const unsafe fn from_raw_parts<'a, T>(data: *const T, len: usize) -> &'a [T] {
     // SAFETY: the caller must uphold the safety contract for `from_raw_parts`.
     unsafe {
-        assert_unsafe_precondition!([T](data: *const T, len: usize) =>
-            is_aligned_and_not_null(data)
-                && crate::mem::size_of::<T>().saturating_mul(len) <= isize::MAX as usize
+        assert_unsafe_precondition!(
+            "slice::from_raw_parts requires the pointer to be aligned and non-null, and the total size of the slice not to exceed `isize::MAX`",
+            [T](data: *const T, len: usize) => is_aligned_and_not_null(data)
+                && is_valid_allocation_size::<T>(len)
         );
         &*ptr::slice_from_raw_parts(data, len)
     }
@@ -134,9 +137,10 @@ pub const unsafe fn from_raw_parts<'a, T>(data: *const T, len: usize) -> &'a [T]
 pub const unsafe fn from_raw_parts_mut<'a, T>(data: *mut T, len: usize) -> &'a mut [T] {
     // SAFETY: the caller must uphold the safety contract for `from_raw_parts_mut`.
     unsafe {
-        assert_unsafe_precondition!([T](data: *mut T, len: usize) =>
-            is_aligned_and_not_null(data)
-                && crate::mem::size_of::<T>().saturating_mul(len) <= isize::MAX as usize
+        assert_unsafe_precondition!(
+            "slice::from_raw_parts_mut requires the pointer to be aligned and non-null, and the total size of the slice not to exceed `isize::MAX`",
+            [T](data: *mut T, len: usize) => is_aligned_and_not_null(data)
+                && is_valid_allocation_size::<T>(len)
         );
         &mut *ptr::slice_from_raw_parts_mut(data, len)
     }
diff --git a/library/core/src/time.rs b/library/core/src/time.rs
index 37c3611d0a90..ba1cb6efa04b 100644
--- a/library/core/src/time.rs
+++ b/library/core/src/time.rs
@@ -1232,7 +1232,7 @@ impl fmt::Debug for Duration {
 /// }
 /// ```
 #[derive(Debug, Clone, PartialEq, Eq)]
-#[stable(feature = "duration_checked_float", since = "CURRENT_RUSTC_VERSION")]
+#[stable(feature = "duration_checked_float", since = "1.66.0")]
 pub struct TryFromFloatSecsError {
     kind: TryFromFloatSecsErrorKind,
 }
@@ -1250,7 +1250,7 @@ impl TryFromFloatSecsError {
     }
 }
 
-#[stable(feature = "duration_checked_float", since = "CURRENT_RUSTC_VERSION")]
+#[stable(feature = "duration_checked_float", since = "1.66.0")]
 impl fmt::Display for TryFromFloatSecsError {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         self.description().fmt(f)
@@ -1401,7 +1401,7 @@ impl Duration {
     /// let res = Duration::try_from_secs_f32(val);
     /// assert_eq!(res, Ok(Duration::new(1, 2_929_688)));
     /// ```
-    #[stable(feature = "duration_checked_float", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "duration_checked_float", since = "1.66.0")]
     #[rustc_const_unstable(feature = "duration_consts_float", issue = "72440")]
     #[inline]
     pub const fn try_from_secs_f32(secs: f32) -> Result<Duration, TryFromFloatSecsError> {
@@ -1478,7 +1478,7 @@ impl Duration {
     /// let res = Duration::try_from_secs_f64(val);
     /// assert_eq!(res, Ok(Duration::new(1, 2_929_688)));
     /// ```
-    #[stable(feature = "duration_checked_float", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "duration_checked_float", since = "1.66.0")]
     #[rustc_const_unstable(feature = "duration_consts_float", issue = "72440")]
     #[inline]
     pub const fn try_from_secs_f64(secs: f64) -> Result<Duration, TryFromFloatSecsError> {
diff --git a/library/core/src/tuple.rs b/library/core/src/tuple.rs
index fc91fe468cc2..28275798f751 100644
--- a/library/core/src/tuple.rs
+++ b/library/core/src/tuple.rs
@@ -22,7 +22,8 @@ macro_rules! tuple_impls {
         maybe_tuple_doc! {
             $($T)+ @
             #[stable(feature = "rust1", since = "1.0.0")]
-            impl<$($T:PartialEq),+> PartialEq for ($($T,)+)
+            #[rustc_const_unstable(feature = "const_cmp", issue = "92391")]
+            impl<$($T: ~const PartialEq),+> const PartialEq for ($($T,)+)
             where
                 last_type!($($T,)+): ?Sized
             {
@@ -40,7 +41,7 @@ macro_rules! tuple_impls {
         maybe_tuple_doc! {
             $($T)+ @
             #[stable(feature = "rust1", since = "1.0.0")]
-            impl<$($T:Eq),+> Eq for ($($T,)+)
+            impl<$($T: Eq),+> Eq for ($($T,)+)
             where
                 last_type!($($T,)+): ?Sized
             {}
@@ -49,7 +50,8 @@ macro_rules! tuple_impls {
         maybe_tuple_doc! {
             $($T)+ @
             #[stable(feature = "rust1", since = "1.0.0")]
-            impl<$($T:PartialOrd + PartialEq),+> PartialOrd for ($($T,)+)
+            #[rustc_const_unstable(feature = "const_cmp", issue = "92391")]
+            impl<$($T: ~const PartialOrd + ~const PartialEq),+> const PartialOrd for ($($T,)+)
             where
                 last_type!($($T,)+): ?Sized
             {
@@ -79,7 +81,8 @@ macro_rules! tuple_impls {
         maybe_tuple_doc! {
             $($T)+ @
             #[stable(feature = "rust1", since = "1.0.0")]
-            impl<$($T:Ord),+> Ord for ($($T,)+)
+            #[rustc_const_unstable(feature = "const_cmp", issue = "92391")]
+            impl<$($T: ~const Ord),+> const Ord for ($($T,)+)
             where
                 last_type!($($T,)+): ?Sized
             {
diff --git a/library/core/tests/any.rs b/library/core/tests/any.rs
index 9538b8139495..e98dac8d12ef 100644
--- a/library/core/tests/any.rs
+++ b/library/core/tests/any.rs
@@ -131,6 +131,24 @@ fn distinct_type_names() {
     assert_ne!(type_name_of_val(Velocity), type_name_of_val(Velocity(0.0, -9.8)),);
 }
 
+#[cfg(not(bootstrap))]
+#[test]
+fn dyn_type_name() {
+    trait Foo {
+        type Bar;
+    }
+
+    assert_eq!(
+        "dyn core::ops::function::Fn(i32, i32) -> i32",
+        std::any::type_name::<dyn Fn(i32, i32) -> i32>()
+    );
+    assert_eq!(
+        "dyn coretests::any::dyn_type_name::Foo<Bar = i32> \
+        + core::marker::Send + core::marker::Sync",
+        std::any::type_name::<dyn Foo<Bar = i32> + Send + Sync>()
+    );
+}
+
 // Test the `Provider` API.
 
 struct SomeConcreteType {
diff --git a/library/core/tests/hash/mod.rs b/library/core/tests/hash/mod.rs
index f7934d062a37..267245f05dcd 100644
--- a/library/core/tests/hash/mod.rs
+++ b/library/core/tests/hash/mod.rs
@@ -9,16 +9,19 @@ struct MyHasher {
     hash: u64,
 }
 
-impl Default for MyHasher {
+impl const Default for MyHasher {
     fn default() -> MyHasher {
         MyHasher { hash: 0 }
     }
 }
 
-impl Hasher for MyHasher {
+impl const Hasher for MyHasher {
     fn write(&mut self, buf: &[u8]) {
-        for byte in buf {
-            self.hash += *byte as u64;
+        // FIXME(const_trait_impl): change to for loop
+        let mut i = 0;
+        while i < buf.len() {
+            self.hash += buf[i] as u64;
+            i += 1;
         }
     }
     fn write_str(&mut self, s: &str) {
@@ -32,12 +35,25 @@ impl Hasher for MyHasher {
 
 #[test]
 fn test_writer_hasher() {
-    fn hash<T: Hash>(t: &T) -> u64 {
+    const fn hash<T: ~const Hash>(t: &T) -> u64 {
         let mut s = MyHasher { hash: 0 };
         t.hash(&mut s);
         s.finish()
     }
 
+    const {
+        // FIXME(fee1-dead): assert_eq
+        assert!(hash(&()) == 0);
+        assert!(hash(&5_u8) == 5);
+        assert!(hash(&5_u16) == 5);
+        assert!(hash(&5_u32) == 5);
+
+        assert!(hash(&'a') == 97);
+
+        let s: &str = "a";
+        assert!(hash(&s) == 97 + 0xFF);
+    };
+
     assert_eq!(hash(&()), 0);
 
     assert_eq!(hash(&5_u8), 5);
@@ -97,7 +113,7 @@ struct CustomHasher {
     output: u64,
 }
 
-impl Hasher for CustomHasher {
+impl const Hasher for CustomHasher {
     fn finish(&self) -> u64 {
         self.output
     }
@@ -109,27 +125,29 @@ impl Hasher for CustomHasher {
     }
 }
 
-impl Default for CustomHasher {
+impl const Default for CustomHasher {
     fn default() -> CustomHasher {
         CustomHasher { output: 0 }
     }
 }
 
-impl Hash for Custom {
-    fn hash<H: Hasher>(&self, state: &mut H) {
+impl const Hash for Custom {
+    fn hash<H: ~const Hasher>(&self, state: &mut H) {
         state.write_u64(self.hash);
     }
 }
 
 #[test]
 fn test_custom_state() {
-    fn hash<T: Hash>(t: &T) -> u64 {
+    const fn hash<T: ~const Hash>(t: &T) -> u64 {
         let mut c = CustomHasher { output: 0 };
         t.hash(&mut c);
         c.finish()
     }
 
     assert_eq!(hash(&Custom { hash: 5 }), 5);
+
+    const { assert!(hash(&Custom { hash: 6 }) == 6) };
 }
 
 // FIXME: Instantiated functions with i128 in the signature is not supported in Emscripten.
diff --git a/library/core/tests/hash/sip.rs b/library/core/tests/hash/sip.rs
index 877d08418305..3abf6efcfa9b 100644
--- a/library/core/tests/hash/sip.rs
+++ b/library/core/tests/hash/sip.rs
@@ -8,7 +8,6 @@ use core::{mem, slice};
 struct Bytes<'a>(&'a [u8]);
 
 impl<'a> Hash for Bytes<'a> {
-    #[allow(unused_must_use)]
     fn hash<H: Hasher>(&self, state: &mut H) {
         let Bytes(v) = *self;
         state.write(v);
@@ -24,6 +23,20 @@ fn hash<T: Hash>(x: &T) -> u64 {
     hash_with(SipHasher::new(), x)
 }
 
+#[test]
+const fn test_const_sip() {
+    let val1 = 0x45;
+    let val2 = 0xfeed;
+
+    const fn const_hash<T: ~const Hash>(x: &T) -> u64 {
+        let mut st = SipHasher::new();
+        x.hash(&mut st);
+        st.finish()
+    }
+
+    assert!(const_hash(&(val1)) != const_hash(&(val2)));
+}
+
 #[test]
 #[allow(unused_must_use)]
 fn test_siphash_1_3() {
diff --git a/library/core/tests/iter/adapters/array_chunks.rs b/library/core/tests/iter/adapters/array_chunks.rs
index 4e9d89e1e580..ef4a7e53bdd3 100644
--- a/library/core/tests/iter/adapters/array_chunks.rs
+++ b/library/core/tests/iter/adapters/array_chunks.rs
@@ -139,7 +139,8 @@ fn test_iterator_array_chunks_fold() {
     let result =
         (0..10).map(|_| CountDrop::new(&count)).array_chunks::<3>().fold(0, |acc, _item| acc + 1);
     assert_eq!(result, 3);
-    assert_eq!(count.get(), 10);
+    // fold impls may or may not process the remainder
+    assert!(count.get() <= 10 && count.get() >= 9);
 }
 
 #[test]
diff --git a/library/core/tests/lib.rs b/library/core/tests/lib.rs
index 3012a78b9c98..61d31b344873 100644
--- a/library/core/tests/lib.rs
+++ b/library/core/tests/lib.rs
@@ -5,11 +5,13 @@
 #![feature(bigint_helper_methods)]
 #![feature(cell_update)]
 #![feature(const_assume)]
+#![feature(const_align_of_val_raw)]
 #![feature(const_black_box)]
 #![feature(const_bool_to_option)]
 #![feature(const_caller_location)]
 #![feature(const_cell_into_inner)]
 #![feature(const_convert)]
+#![feature(const_hash)]
 #![feature(const_heap)]
 #![feature(const_maybe_uninit_as_mut_ptr)]
 #![feature(const_maybe_uninit_assume_init_read)]
@@ -42,6 +44,7 @@
 #![feature(try_find)]
 #![feature(inline_const)]
 #![feature(is_sorted)]
+#![feature(layout_for_ptr)]
 #![feature(pattern)]
 #![feature(pin_macro)]
 #![feature(sort_internals)]
@@ -62,7 +65,6 @@
 #![feature(try_trait_v2)]
 #![feature(slice_internals)]
 #![feature(slice_partition_dedup)]
-#![feature(int_log)]
 #![feature(iter_advance_by)]
 #![feature(iter_array_chunks)]
 #![feature(iter_collect_into)]
@@ -95,7 +97,6 @@
 #![feature(strict_provenance_atomic_ptr)]
 #![feature(trusted_random_access)]
 #![feature(unsize)]
-#![feature(unzip_option)]
 #![feature(const_array_from_ref)]
 #![feature(const_slice_from_ref)]
 #![feature(waker_getters)]
diff --git a/library/core/tests/mem.rs b/library/core/tests/mem.rs
index 0362e1c8afb5..1cfb4fd9fd18 100644
--- a/library/core/tests/mem.rs
+++ b/library/core/tests/mem.rs
@@ -1,4 +1,5 @@
 use core::mem::*;
+use core::ptr;
 
 #[cfg(panic = "unwind")]
 use std::rc::Rc;
@@ -75,6 +76,25 @@ fn align_of_val_basic() {
     assert_eq!(align_of_val(&1u32), 4);
 }
 
+#[test]
+#[cfg(not(bootstrap))] // stage 0 doesn't have the fix yet, so the test fails
+fn align_of_val_raw_packed() {
+    #[repr(C, packed)]
+    struct B {
+        f: [u32],
+    }
+    let storage = [0u8; 4];
+    let b: *const B = ptr::from_raw_parts(storage.as_ptr().cast(), 1);
+    assert_eq!(unsafe { align_of_val_raw(b) }, 1);
+
+    const ALIGN_OF_VAL_RAW: usize = {
+        let storage = [0u8; 4];
+        let b: *const B = ptr::from_raw_parts(storage.as_ptr().cast(), 1);
+        unsafe { align_of_val_raw(b) }
+    };
+    assert_eq!(ALIGN_OF_VAL_RAW, 1);
+}
+
 #[test]
 fn test_swap() {
     let mut x = 31337;
diff --git a/library/core/tests/option.rs b/library/core/tests/option.rs
index f36f7c268064..dca6321cf62f 100644
--- a/library/core/tests/option.rs
+++ b/library/core/tests/option.rs
@@ -57,7 +57,7 @@ fn test_get_resource() {
 }
 
 #[test]
-#[cfg_attr(not(bootstrap), allow(for_loops_over_fallibles))]
+#[allow(for_loops_over_fallibles)]
 fn test_option_dance() {
     let x = Some(());
     let mut y = Some(5);
diff --git a/library/panic_abort/Cargo.toml b/library/panic_abort/Cargo.toml
index 46183d1ad006..e6ea2b1849b4 100644
--- a/library/panic_abort/Cargo.toml
+++ b/library/panic_abort/Cargo.toml
@@ -13,7 +13,7 @@ doc = false
 
 [dependencies]
 alloc = { path = "../alloc" }
-cfg-if = { version = "0.1.8", features = ['rustc-dep-of-std'] }
+cfg-if = { version = "1.0", features = ['rustc-dep-of-std'] }
 core = { path = "../core" }
 libc = { version = "0.2", default-features = false }
 compiler_builtins = "0.1.0"
diff --git a/library/panic_unwind/Cargo.toml b/library/panic_unwind/Cargo.toml
index d720cc7bcbdf..85386976d639 100644
--- a/library/panic_unwind/Cargo.toml
+++ b/library/panic_unwind/Cargo.toml
@@ -17,4 +17,4 @@ core = { path = "../core" }
 libc = { version = "0.2", default-features = false }
 unwind = { path = "../unwind" }
 compiler_builtins = "0.1.0"
-cfg-if = "0.1.8"
+cfg-if = "1.0"
diff --git a/library/panic_unwind/src/emcc.rs b/library/panic_unwind/src/emcc.rs
index 7c233c7c3a1c..c6d42308596c 100644
--- a/library/panic_unwind/src/emcc.rs
+++ b/library/panic_unwind/src/emcc.rs
@@ -47,7 +47,12 @@ static EXCEPTION_TYPE_INFO: TypeInfo = TypeInfo {
     name: b"rust_panic\0".as_ptr(),
 };
 
+// NOTE(nbdd0121): The `canary` field will be part of stable ABI after `c_unwind` stabilization.
+#[repr(C)]
 struct Exception {
+    // See `gcc.rs` on why this is present. We already have a static here so just use it.
+    canary: *const TypeInfo,
+
     // This is necessary because C++ code can capture our exception with
     // std::exception_ptr and rethrow it multiple times, possibly even in
     // another thread.
@@ -70,27 +75,38 @@ pub unsafe fn cleanup(ptr: *mut u8) -> Box<dyn Any + Send> {
     let catch_data = &*(ptr as *mut CatchData);
 
     let adjusted_ptr = __cxa_begin_catch(catch_data.ptr as *mut libc::c_void) as *mut Exception;
-    let out = if catch_data.is_rust_panic {
-        let was_caught = (*adjusted_ptr).caught.swap(true, Ordering::SeqCst);
-        if was_caught {
-            // Since cleanup() isn't allowed to panic, we just abort instead.
-            intrinsics::abort();
-        }
-        (*adjusted_ptr).data.take().unwrap()
-    } else {
+    if !catch_data.is_rust_panic {
         super::__rust_foreign_exception();
-    };
+    }
+
+    let canary = ptr::addr_of!((*adjusted_ptr).canary).read();
+    if !ptr::eq(canary, &EXCEPTION_TYPE_INFO) {
+        super::__rust_foreign_exception();
+    }
+
+    let was_caught = (*adjusted_ptr).caught.swap(true, Ordering::SeqCst);
+    if was_caught {
+        // Since cleanup() isn't allowed to panic, we just abort instead.
+        intrinsics::abort();
+    }
+    let out = (*adjusted_ptr).data.take().unwrap();
     __cxa_end_catch();
     out
 }
 
 pub unsafe fn panic(data: Box<dyn Any + Send>) -> u32 {
-    let sz = mem::size_of_val(&data);
-    let exception = __cxa_allocate_exception(sz) as *mut Exception;
+    let exception = __cxa_allocate_exception(mem::size_of::<Exception>()) as *mut Exception;
     if exception.is_null() {
         return uw::_URC_FATAL_PHASE1_ERROR as u32;
     }
-    ptr::write(exception, Exception { caught: AtomicBool::new(false), data: Some(data) });
+    ptr::write(
+        exception,
+        Exception {
+            canary: &EXCEPTION_TYPE_INFO,
+            caught: AtomicBool::new(false),
+            data: Some(data),
+        },
+    );
     __cxa_throw(exception as *mut _, &EXCEPTION_TYPE_INFO, exception_cleanup);
 }
 
diff --git a/library/panic_unwind/src/gcc.rs b/library/panic_unwind/src/gcc.rs
index 261404e8795f..0b7a873a691c 100644
--- a/library/panic_unwind/src/gcc.rs
+++ b/library/panic_unwind/src/gcc.rs
@@ -38,12 +38,23 @@
 
 use alloc::boxed::Box;
 use core::any::Any;
+use core::ptr;
 
 use unwind as uw;
 
+// In case where multiple copies of std exist in a single process,
+// we use address of this static variable to distinguish an exception raised by
+// this copy and some other copy (which needs to be treated as foreign exception).
+static CANARY: u8 = 0;
+
+// NOTE(nbdd0121)
+// Once `c_unwind` feature is stabilized, there will be ABI stability requirement
+// on this struct. The first two field must be `_Unwind_Exception` and `canary`,
+// as it may be accessed by a different version of the std with a different compiler.
 #[repr(C)]
 struct Exception {
     _uwe: uw::_Unwind_Exception,
+    canary: *const u8,
     cause: Box<dyn Any + Send>,
 }
 
@@ -54,6 +65,7 @@ pub unsafe fn panic(data: Box<dyn Any + Send>) -> u32 {
             exception_cleanup,
             private: [0; uw::unwinder_private_data_size],
         },
+        canary: &CANARY,
         cause: data,
     });
     let exception_param = Box::into_raw(exception) as *mut uw::_Unwind_Exception;
@@ -75,10 +87,22 @@ pub unsafe fn cleanup(ptr: *mut u8) -> Box<dyn Any + Send> {
     if (*exception).exception_class != rust_exception_class() {
         uw::_Unwind_DeleteException(exception);
         super::__rust_foreign_exception();
-    } else {
-        let exception = Box::from_raw(exception as *mut Exception);
-        exception.cause
     }
+
+    let exception = exception.cast::<Exception>();
+    // Just access the canary field, avoid accessing the entire `Exception` as
+    // it can be a foreign Rust exception.
+    let canary = ptr::addr_of!((*exception).canary).read();
+    if !ptr::eq(canary, &CANARY) {
+        // A foreign Rust exception, treat it slightly differently from other
+        // foreign exceptions, because call into `_Unwind_DeleteException` will
+        // call into `__rust_drop_panic` which produces a confusing
+        // "Rust panic must be rethrown" message.
+        super::__rust_foreign_exception();
+    }
+
+    let exception = Box::from_raw(exception as *mut Exception);
+    exception.cause
 }
 
 // Rust's exception class identifier.  This is used by personality routines to
diff --git a/library/panic_unwind/src/seh.rs b/library/panic_unwind/src/seh.rs
index 6b8d06568611..651115a8248a 100644
--- a/library/panic_unwind/src/seh.rs
+++ b/library/panic_unwind/src/seh.rs
@@ -49,9 +49,15 @@
 use alloc::boxed::Box;
 use core::any::Any;
 use core::mem::{self, ManuallyDrop};
+use core::ptr;
 use libc::{c_int, c_uint, c_void};
 
+// NOTE(nbdd0121): The `canary` field will be part of stable ABI after `c_unwind` stabilization.
+#[repr(C)]
 struct Exception {
+    // See `gcc.rs` on why this is present. We already have a static here so just use it.
+    canary: *const _TypeDescriptor,
+
     // This needs to be an Option because we catch the exception by reference
     // and its destructor is executed by the C++ runtime. When we take the Box
     // out of the exception, we need to leave the exception in a valid state
@@ -235,7 +241,7 @@ static mut TYPE_DESCRIPTOR: _TypeDescriptor = _TypeDescriptor {
 macro_rules! define_cleanup {
     ($abi:tt $abi2:tt) => {
         unsafe extern $abi fn exception_cleanup(e: *mut Exception) {
-            if let Exception { data: Some(b) } = e.read() {
+            if let Exception { data: Some(b), .. } = e.read() {
                 drop(b);
                 super::__rust_drop_panic();
             }
@@ -265,7 +271,7 @@ pub unsafe fn panic(data: Box<dyn Any + Send>) -> u32 {
     // The ManuallyDrop is needed here since we don't want Exception to be
     // dropped when unwinding. Instead it will be dropped by exception_cleanup
     // which is invoked by the C++ runtime.
-    let mut exception = ManuallyDrop::new(Exception { data: Some(data) });
+    let mut exception = ManuallyDrop::new(Exception { canary: &TYPE_DESCRIPTOR, data: Some(data) });
     let throw_ptr = &mut exception as *mut _ as *mut _;
 
     // This... may seems surprising, and justifiably so. On 32-bit MSVC the
@@ -321,8 +327,12 @@ pub unsafe fn cleanup(payload: *mut u8) -> Box<dyn Any + Send> {
     // __rust_try. This happens when a non-Rust foreign exception is caught.
     if payload.is_null() {
         super::__rust_foreign_exception();
-    } else {
-        let exception = &mut *(payload as *mut Exception);
-        exception.data.take().unwrap()
     }
+    let exception = payload as *mut Exception;
+    let canary = ptr::addr_of!((*exception).canary).read();
+    if !ptr::eq(canary, &TYPE_DESCRIPTOR) {
+        // A foreign Rust exception.
+        super::__rust_foreign_exception();
+    }
+    (*exception).data.take().unwrap()
 }
diff --git a/library/portable-simd/crates/core_simd/src/intrinsics.rs b/library/portable-simd/crates/core_simd/src/intrinsics.rs
index 962c83a78cb3..704e6ed0159f 100644
--- a/library/portable-simd/crates/core_simd/src/intrinsics.rs
+++ b/library/portable-simd/crates/core_simd/src/intrinsics.rs
@@ -103,7 +103,7 @@ extern "platform-intrinsic" {
     /// val: vector of values to select if a lane is masked
     /// ptr: vector of pointers to read from
     /// mask: a "wide" mask of integers, selects as if simd_select(mask, read(ptr), val)
-    /// note, the LLVM intrinsic accepts a mask vector of <N x i1>
+    /// note, the LLVM intrinsic accepts a mask vector of `<N x i1>`
     /// FIXME: review this if/when we fix up our mask story in general?
     pub(crate) fn simd_gather<T, U, V>(val: T, ptr: U, mask: V) -> T;
     /// llvm.masked.scatter
diff --git a/library/portable-simd/crates/core_simd/src/ops.rs b/library/portable-simd/crates/core_simd/src/ops.rs
index 5a077a469d83..fc1e0bc426df 100644
--- a/library/portable-simd/crates/core_simd/src/ops.rs
+++ b/library/portable-simd/crates/core_simd/src/ops.rs
@@ -40,7 +40,7 @@ macro_rules! unsafe_base {
 
 /// SAFETY: This macro should not be used for anything except Shl or Shr, and passed the appropriate shift intrinsic.
 /// It handles performing a bitand in addition to calling the shift operator, so that the result
-/// is well-defined: LLVM can return a poison value if you shl, lshr, or ashr if rhs >= <Int>::BITS
+/// is well-defined: LLVM can return a poison value if you shl, lshr, or ashr if `rhs >= <Int>::BITS`
 /// At worst, this will maybe add another instruction and cycle,
 /// at best, it may open up more optimization opportunities,
 /// or simply be elided entirely, especially for SIMD ISAs which default to this.
diff --git a/library/proc_macro/src/lib.rs b/library/proc_macro/src/lib.rs
index 8001fcff6484..0d3fc2c5244e 100644
--- a/library/proc_macro/src/lib.rs
+++ b/library/proc_macro/src/lib.rs
@@ -546,7 +546,7 @@ impl Span {
     /// Note: The observable result of a macro should only rely on the tokens and
     /// not on this source text. The result of this function is a best effort to
     /// be used for diagnostics only.
-    #[stable(feature = "proc_macro_source_text", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "proc_macro_source_text", since = "1.66.0")]
     pub fn source_text(&self) -> Option<String> {
         self.0.source_text()
     }
diff --git a/library/std/Cargo.toml b/library/std/Cargo.toml
index bc10b12ec2af..c10bfde4ddf7 100644
--- a/library/std/Cargo.toml
+++ b/library/std/Cargo.toml
@@ -16,18 +16,18 @@ panic_unwind = { path = "../panic_unwind", optional = true }
 panic_abort = { path = "../panic_abort" }
 core = { path = "../core" }
 libc = { version = "0.2.135", default-features = false, features = ['rustc-dep-of-std'] }
-compiler_builtins = { version = "0.1.73" }
+compiler_builtins = { version = "0.1.82" }
 profiler_builtins = { path = "../profiler_builtins", optional = true }
 unwind = { path = "../unwind" }
 hashbrown = { version = "0.12", default-features = false, features = ['rustc-dep-of-std'] }
 std_detect = { path = "../stdarch/crates/std_detect", default-features = false, features = ['rustc-dep-of-std'] }
 
 # Dependencies of the `backtrace` crate
-addr2line = { version = "0.16.0", optional = true, default-features = false }
+addr2line = { version = "0.17.0", optional = true, default-features = false }
 rustc-demangle = { version = "0.1.21", features = ['rustc-dep-of-std'] }
-miniz_oxide = { version = "0.4.0", optional = true, default-features = false }
+miniz_oxide = { version = "0.5.0", optional = true, default-features = false }
 [dependencies.object]
-version = "0.26.1"
+version = "0.29.0"
 optional = true
 default-features = false
 features = ['read_core', 'elf', 'macho', 'pe', 'unaligned', 'archive']
diff --git a/library/std/src/collections/hash/map.rs b/library/std/src/collections/hash/map.rs
index 34983b976e3e..df490358827e 100644
--- a/library/std/src/collections/hash/map.rs
+++ b/library/std/src/collections/hash/map.rs
@@ -759,7 +759,7 @@ where
 
     /// Tries to reserve capacity for at least `additional` more elements to be inserted
     /// in the `HashMap`. The collection may reserve more space to speculatively
-    /// avoid frequent reallocations. After calling `reserve`,
+    /// avoid frequent reallocations. After calling `try_reserve`,
     /// capacity will be greater than or equal to `self.len() + additional` if
     /// it returns `Ok(())`.
     /// Does nothing if capacity is already sufficient.
@@ -3161,14 +3161,16 @@ impl DefaultHasher {
     #[stable(feature = "hashmap_default_hasher", since = "1.13.0")]
     #[inline]
     #[allow(deprecated)]
+    #[rustc_const_unstable(feature = "const_hash", issue = "104061")]
     #[must_use]
-    pub fn new() -> DefaultHasher {
+    pub const fn new() -> DefaultHasher {
         DefaultHasher(SipHasher13::new_with_keys(0, 0))
     }
 }
 
 #[stable(feature = "hashmap_default_hasher", since = "1.13.0")]
-impl Default for DefaultHasher {
+#[rustc_const_unstable(feature = "const_hash", issue = "104061")]
+impl const Default for DefaultHasher {
     /// Creates a new `DefaultHasher` using [`new`].
     /// See its documentation for more.
     ///
@@ -3180,7 +3182,8 @@ impl Default for DefaultHasher {
 }
 
 #[stable(feature = "hashmap_default_hasher", since = "1.13.0")]
-impl Hasher for DefaultHasher {
+#[rustc_const_unstable(feature = "const_hash", issue = "104061")]
+impl const Hasher for DefaultHasher {
     // The underlying `SipHasher13` doesn't override the other
     // `write_*` methods, so it's ok not to forward them here.
 
diff --git a/library/std/src/collections/hash/set.rs b/library/std/src/collections/hash/set.rs
index c36eeae3388d..cee884145c71 100644
--- a/library/std/src/collections/hash/set.rs
+++ b/library/std/src/collections/hash/set.rs
@@ -462,7 +462,7 @@ where
 
     /// Tries to reserve capacity for at least `additional` more elements to be inserted
     /// in the `HashSet`. The collection may reserve more space to speculatively
-    /// avoid frequent reallocations. After calling `reserve`,
+    /// avoid frequent reallocations. After calling `try_reserve`,
     /// capacity will be greater than or equal to `self.len() + additional` if
     /// it returns `Ok(())`.
     /// Does nothing if capacity is already sufficient.
diff --git a/library/std/src/f32.rs b/library/std/src/f32.rs
index 3dd5b12507fb..4127c4056f24 100644
--- a/library/std/src/f32.rs
+++ b/library/std/src/f32.rs
@@ -77,9 +77,11 @@ impl f32 {
     /// ```
     /// let f = 3.3_f32;
     /// let g = -3.3_f32;
+    /// let h = -3.7_f32;
     ///
     /// assert_eq!(f.round(), 3.0);
     /// assert_eq!(g.round(), -3.0);
+    /// assert_eq!(h.round(), -4.0);
     /// ```
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
@@ -275,7 +277,7 @@ impl f32 {
     /// This result is not an element of the function's codomain, but it is the
     /// closest floating point number in the real numbers and thus fulfills the
     /// property `self == self.div_euclid(rhs) * rhs + self.rem_euclid(rhs)`
-    /// approximatively.
+    /// approximately.
     ///
     /// # Examples
     ///
diff --git a/library/std/src/f64.rs b/library/std/src/f64.rs
index 31351a87978c..cc64258da60d 100644
--- a/library/std/src/f64.rs
+++ b/library/std/src/f64.rs
@@ -77,9 +77,11 @@ impl f64 {
     /// ```
     /// let f = 3.3_f64;
     /// let g = -3.3_f64;
+    /// let h = -3.7_f64;
     ///
     /// assert_eq!(f.round(), 3.0);
     /// assert_eq!(g.round(), -3.0);
+    /// assert_eq!(h.round(), -4.0);
     /// ```
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
@@ -275,7 +277,7 @@ impl f64 {
     /// This result is not an element of the function's codomain, but it is the
     /// closest floating point number in the real numbers and thus fulfills the
     /// property `self == self.div_euclid(rhs) * rhs + self.rem_euclid(rhs)`
-    /// approximatively.
+    /// approximately.
     ///
     /// # Examples
     ///
diff --git a/library/std/src/lib.rs b/library/std/src/lib.rs
index 385585dada89..9334c833bb65 100644
--- a/library/std/src/lib.rs
+++ b/library/std/src/lib.rs
@@ -352,6 +352,7 @@
 //
 // Only for const-ness:
 #![feature(const_collections_with_hasher)]
+#![feature(const_hash)]
 #![feature(const_io_structs)]
 #![feature(const_ip)]
 #![feature(const_ipv4)]
diff --git a/library/std/src/net/ip_addr.rs b/library/std/src/net/ip_addr.rs
index 4f14fc28038a..5453853e1381 100644
--- a/library/std/src/net/ip_addr.rs
+++ b/library/std/src/net/ip_addr.rs
@@ -73,7 +73,6 @@ pub enum IpAddr {
 /// assert!("0xcb.0x0.0x71.0x00".parse::<Ipv4Addr>().is_err()); // all octets are in hex
 /// ```
 #[derive(Copy, Clone, PartialEq, Eq, Hash)]
-#[cfg_attr(not(test), rustc_diagnostic_item = "Ipv4Addr")]
 #[stable(feature = "rust1", since = "1.0.0")]
 pub struct Ipv4Addr {
     octets: [u8; 4],
@@ -156,7 +155,6 @@ pub struct Ipv4Addr {
 /// assert_eq!(localhost.is_loopback(), true);
 /// ```
 #[derive(Copy, Clone, PartialEq, Eq, Hash)]
-#[cfg_attr(not(test), rustc_diagnostic_item = "Ipv6Addr")]
 #[stable(feature = "rust1", since = "1.0.0")]
 pub struct Ipv6Addr {
     octets: [u8; 16],
diff --git a/library/std/src/net/mod.rs b/library/std/src/net/mod.rs
index 01e3db9de51c..19d90e7ec383 100644
--- a/library/std/src/net/mod.rs
+++ b/library/std/src/net/mod.rs
@@ -11,7 +11,7 @@
 //!   [`Ipv6Addr`] are respectively IPv4 and IPv6 addresses
 //! * [`SocketAddr`] represents socket addresses of either IPv4 or IPv6; [`SocketAddrV4`]
 //!   and [`SocketAddrV6`] are respectively IPv4 and IPv6 socket addresses
-//! * [`ToSocketAddrs`] is a trait that used for generic address resolution when interacting
+//! * [`ToSocketAddrs`] is a trait that is used for generic address resolution when interacting
 //!   with networking objects like [`TcpListener`], [`TcpStream`] or [`UdpSocket`]
 //! * Other types are return or parameter types for various methods in this module
 //!
diff --git a/library/std/src/os/android/net.rs b/library/std/src/os/android/net.rs
index ff96125c37bd..7cecd1bbfaa9 100644
--- a/library/std/src/os/android/net.rs
+++ b/library/std/src/os/android/net.rs
@@ -1,4 +1,9 @@
-//! Linux and Android-specific definitions for socket options.
+//! Android-specific networking functionality.
 
 #![unstable(feature = "tcp_quickack", issue = "96256")]
-pub use crate::os::net::tcp::TcpStreamExt;
+
+#[unstable(feature = "unix_socket_abstract", issue = "85410")]
+pub use crate::os::net::linux_ext::addr::SocketAddrExt;
+
+#[unstable(feature = "tcp_quickack", issue = "96256")]
+pub use crate::os::net::linux_ext::tcp::TcpStreamExt;
diff --git a/library/std/src/os/linux/net.rs b/library/std/src/os/linux/net.rs
index ff96125c37bd..94081c8dd31c 100644
--- a/library/std/src/os/linux/net.rs
+++ b/library/std/src/os/linux/net.rs
@@ -1,4 +1,9 @@
-//! Linux and Android-specific definitions for socket options.
+//! Linux-specific networking functionality.
 
 #![unstable(feature = "tcp_quickack", issue = "96256")]
-pub use crate::os::net::tcp::TcpStreamExt;
+
+#[unstable(feature = "unix_socket_abstract", issue = "85410")]
+pub use crate::os::net::linux_ext::addr::SocketAddrExt;
+
+#[unstable(feature = "tcp_quickack", issue = "96256")]
+pub use crate::os::net::linux_ext::tcp::TcpStreamExt;
diff --git a/library/std/src/os/net/linux_ext/addr.rs b/library/std/src/os/net/linux_ext/addr.rs
new file mode 100644
index 000000000000..df3fc8e6a3b6
--- /dev/null
+++ b/library/std/src/os/net/linux_ext/addr.rs
@@ -0,0 +1,64 @@
+//! Linux and Android-specific extensions to socket addresses.
+
+use crate::os::unix::net::SocketAddr;
+use crate::sealed::Sealed;
+
+/// Platform-specific extensions to [`SocketAddr`].
+#[unstable(feature = "unix_socket_abstract", issue = "85410")]
+pub trait SocketAddrExt: Sealed {
+    /// Creates a Unix socket address in the abstract namespace.
+    ///
+    /// The abstract namespace is a Linux-specific extension that allows Unix
+    /// sockets to be bound without creating an entry in the filesystem.
+    /// Abstract sockets are unaffected by filesystem layout or permissions,
+    /// and no cleanup is necessary when the socket is closed.
+    ///
+    /// An abstract socket address name may contain any bytes, including zero.
+    ///
+    /// # Errors
+    ///
+    /// Returns an error if the name is longer than `SUN_LEN - 1`.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// #![feature(unix_socket_abstract)]
+    /// use std::os::unix::net::{UnixListener, SocketAddr};
+    /// use std::os::linux::net::SocketAddrExt;
+    ///
+    /// fn main() -> std::io::Result<()> {
+    ///     let addr = SocketAddr::from_abstract_name(b"hidden")?;
+    ///     let listener = match UnixListener::bind_addr(&addr) {
+    ///         Ok(sock) => sock,
+    ///         Err(err) => {
+    ///             println!("Couldn't bind: {err:?}");
+    ///             return Err(err);
+    ///         }
+    ///     };
+    ///     Ok(())
+    /// }
+    /// ```
+    fn from_abstract_name<N>(name: &N) -> crate::io::Result<SocketAddr>
+    where
+        N: AsRef<[u8]>;
+
+    /// Returns the contents of this address if it is in the abstract namespace.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// #![feature(unix_socket_abstract)]
+    /// use std::os::unix::net::{UnixListener, SocketAddr};
+    /// use std::os::linux::net::SocketAddrExt;
+    ///
+    /// fn main() -> std::io::Result<()> {
+    ///     let name = b"hidden";
+    ///     let name_addr = SocketAddr::from_abstract_name(name)?;
+    ///     let socket = UnixListener::bind_addr(&name_addr)?;
+    ///     let local_addr = socket.local_addr().expect("Couldn't get local address");
+    ///     assert_eq!(local_addr.as_abstract_name(), Some(&name[..]));
+    ///     Ok(())
+    /// }
+    /// ```
+    fn as_abstract_name(&self) -> Option<&[u8]>;
+}
diff --git a/library/std/src/os/net/linux_ext/mod.rs b/library/std/src/os/net/linux_ext/mod.rs
new file mode 100644
index 000000000000..318ebacfd7a0
--- /dev/null
+++ b/library/std/src/os/net/linux_ext/mod.rs
@@ -0,0 +1,12 @@
+//! Linux and Android-specific networking functionality.
+
+#![doc(cfg(any(target_os = "linux", target_os = "android")))]
+
+#[unstable(feature = "unix_socket_abstract", issue = "85410")]
+pub(crate) mod addr;
+
+#[unstable(feature = "tcp_quickack", issue = "96256")]
+pub(crate) mod tcp;
+
+#[cfg(test)]
+mod tests;
diff --git a/library/std/src/os/net/tcp.rs b/library/std/src/os/net/linux_ext/tcp.rs
similarity index 100%
rename from library/std/src/os/net/tcp.rs
rename to library/std/src/os/net/linux_ext/tcp.rs
diff --git a/library/std/src/os/net/tests.rs b/library/std/src/os/net/linux_ext/tests.rs
similarity index 88%
rename from library/std/src/os/net/tests.rs
rename to library/std/src/os/net/linux_ext/tests.rs
index 4704e3156913..2db4deed0363 100644
--- a/library/std/src/os/net/tests.rs
+++ b/library/std/src/os/net/linux_ext/tests.rs
@@ -1,9 +1,8 @@
-#[cfg(any(target_os = "android", target_os = "linux",))]
 #[test]
 fn quickack() {
     use crate::{
         net::{test::next_test_ip4, TcpListener, TcpStream},
-        os::net::tcp::TcpStreamExt,
+        os::net::linux_ext::tcp::TcpStreamExt,
     };
 
     macro_rules! t {
diff --git a/library/std/src/os/net/mod.rs b/library/std/src/os/net/mod.rs
index d6d84d24ec48..5ec267c41e97 100644
--- a/library/std/src/os/net/mod.rs
+++ b/library/std/src/os/net/mod.rs
@@ -1,7 +1,4 @@
-//! Linux and Android-specific definitions for socket options.
+//! OS-specific networking functionality.
 
-#![unstable(feature = "tcp_quickack", issue = "96256")]
-#![doc(cfg(any(target_os = "linux", target_os = "android",)))]
-pub mod tcp;
-#[cfg(test)]
-mod tests;
+#[cfg(any(target_os = "linux", target_os = "android", doc))]
+pub(super) mod linux_ext;
diff --git a/library/std/src/os/unix/net/addr.rs b/library/std/src/os/unix/net/addr.rs
index 094085e19428..81ac829d21bc 100644
--- a/library/std/src/os/unix/net/addr.rs
+++ b/library/std/src/os/unix/net/addr.rs
@@ -1,6 +1,9 @@
 use crate::ffi::OsStr;
+#[cfg(any(doc, target_os = "android", target_os = "linux"))]
+use crate::os::net::linux_ext;
 use crate::os::unix::ffi::OsStrExt;
 use crate::path::Path;
+use crate::sealed::Sealed;
 use crate::sys::cvt;
 use crate::{fmt, io, mem, ptr};
 
@@ -224,31 +227,6 @@ impl SocketAddr {
         if let AddressKind::Pathname(path) = self.address() { Some(path) } else { None }
     }
 
-    /// Returns the contents of this address if it is an abstract namespace
-    /// without the leading null byte.
-    ///
-    /// # Examples
-    ///
-    /// ```no_run
-    /// #![feature(unix_socket_abstract)]
-    /// use std::os::unix::net::{UnixListener, SocketAddr};
-    ///
-    /// fn main() -> std::io::Result<()> {
-    ///     let namespace = b"hidden";
-    ///     let namespace_addr = SocketAddr::from_abstract_namespace(&namespace[..])?;
-    ///     let socket = UnixListener::bind_addr(&namespace_addr)?;
-    ///     let local_addr = socket.local_addr().expect("Couldn't get local address");
-    ///     assert_eq!(local_addr.as_abstract_namespace(), Some(&namespace[..]));
-    ///     Ok(())
-    /// }
-    /// ```
-    #[doc(cfg(any(target_os = "android", target_os = "linux")))]
-    #[cfg(any(doc, target_os = "android", target_os = "linux",))]
-    #[unstable(feature = "unix_socket_abstract", issue = "85410")]
-    pub fn as_abstract_namespace(&self) -> Option<&[u8]> {
-        if let AddressKind::Abstract(name) = self.address() { Some(name) } else { None }
-    }
-
     fn address(&self) -> AddressKind<'_> {
         let len = self.len as usize - sun_path_offset(&self.addr);
         let path = unsafe { mem::transmute::<&[libc::c_char], &[u8]>(&self.addr.sun_path) };
@@ -265,62 +243,41 @@ impl SocketAddr {
             AddressKind::Pathname(OsStr::from_bytes(&path[..len - 1]).as_ref())
         }
     }
+}
 
-    /// Creates an abstract domain socket address from a namespace
-    ///
-    /// An abstract address does not create a file unlike traditional path-based
-    /// Unix sockets. The advantage of this is that the address will disappear when
-    /// the socket bound to it is closed, so no filesystem clean up is required.
-    ///
-    /// The leading null byte for the abstract namespace is automatically added.
-    ///
-    /// This is a Linux-specific extension. See more at [`unix(7)`].
-    ///
-    /// [`unix(7)`]: https://man7.org/linux/man-pages/man7/unix.7.html
-    ///
-    /// # Errors
-    ///
-    /// This will return an error if the given namespace is too long
-    ///
-    /// # Examples
-    ///
-    /// ```no_run
-    /// #![feature(unix_socket_abstract)]
-    /// use std::os::unix::net::{UnixListener, SocketAddr};
-    ///
-    /// fn main() -> std::io::Result<()> {
-    ///     let addr = SocketAddr::from_abstract_namespace(b"hidden")?;
-    ///     let listener = match UnixListener::bind_addr(&addr) {
-    ///         Ok(sock) => sock,
-    ///         Err(err) => {
-    ///             println!("Couldn't bind: {err:?}");
-    ///             return Err(err);
-    ///         }
-    ///     };
-    ///     Ok(())
-    /// }
-    /// ```
-    #[doc(cfg(any(target_os = "android", target_os = "linux")))]
-    #[cfg(any(doc, target_os = "android", target_os = "linux",))]
-    #[unstable(feature = "unix_socket_abstract", issue = "85410")]
-    pub fn from_abstract_namespace(namespace: &[u8]) -> io::Result<SocketAddr> {
+#[unstable(feature = "unix_socket_abstract", issue = "85410")]
+impl Sealed for SocketAddr {}
+
+#[doc(cfg(any(target_os = "android", target_os = "linux")))]
+#[cfg(any(doc, target_os = "android", target_os = "linux"))]
+#[unstable(feature = "unix_socket_abstract", issue = "85410")]
+impl linux_ext::addr::SocketAddrExt for SocketAddr {
+    fn as_abstract_name(&self) -> Option<&[u8]> {
+        if let AddressKind::Abstract(name) = self.address() { Some(name) } else { None }
+    }
+
+    fn from_abstract_name<N>(name: &N) -> crate::io::Result<Self>
+    where
+        N: AsRef<[u8]>,
+    {
+        let name = name.as_ref();
         unsafe {
             let mut addr: libc::sockaddr_un = mem::zeroed();
             addr.sun_family = libc::AF_UNIX as libc::sa_family_t;
 
-            if namespace.len() + 1 > addr.sun_path.len() {
+            if name.len() + 1 > addr.sun_path.len() {
                 return Err(io::const_io_error!(
                     io::ErrorKind::InvalidInput,
-                    "namespace must be shorter than SUN_LEN",
+                    "abstract socket name must be shorter than SUN_LEN",
                 ));
             }
 
             crate::ptr::copy_nonoverlapping(
-                namespace.as_ptr(),
+                name.as_ptr(),
                 addr.sun_path.as_mut_ptr().add(1) as *mut u8,
-                namespace.len(),
+                name.len(),
             );
-            let len = (sun_path_offset(&addr) + 1 + namespace.len()) as libc::socklen_t;
+            let len = (sun_path_offset(&addr) + 1 + name.len()) as libc::socklen_t;
             SocketAddr::from_parts(addr, len)
         }
     }
diff --git a/library/std/src/os/unix/net/tests.rs b/library/std/src/os/unix/net/tests.rs
index e4499f9b6a6d..37fcfa8446b0 100644
--- a/library/std/src/os/unix/net/tests.rs
+++ b/library/std/src/os/unix/net/tests.rs
@@ -7,6 +7,12 @@ use crate::sys_common::io::test::tmpdir;
 use crate::thread;
 use crate::time::Duration;
 
+#[cfg(target_os = "android")]
+use crate::os::android::net::SocketAddrExt;
+
+#[cfg(target_os = "linux")]
+use crate::os::linux::net::SocketAddrExt;
+
 macro_rules! or_panic {
     ($e:expr) => {
         match $e {
@@ -404,7 +410,7 @@ fn test_abstract_stream_connect() {
     let msg1 = b"hello";
     let msg2 = b"world";
 
-    let socket_addr = or_panic!(SocketAddr::from_abstract_namespace(b"namespace"));
+    let socket_addr = or_panic!(SocketAddr::from_abstract_name(b"name"));
     let listener = or_panic!(UnixListener::bind_addr(&socket_addr));
 
     let thread = thread::spawn(move || {
@@ -418,7 +424,7 @@ fn test_abstract_stream_connect() {
     let mut stream = or_panic!(UnixStream::connect_addr(&socket_addr));
 
     let peer = or_panic!(stream.peer_addr());
-    assert_eq!(peer.as_abstract_namespace().unwrap(), b"namespace");
+    assert_eq!(peer.as_abstract_name().unwrap(), b"name");
 
     or_panic!(stream.write_all(msg1));
     let mut buf = vec![];
@@ -432,7 +438,7 @@ fn test_abstract_stream_connect() {
 #[cfg(any(target_os = "android", target_os = "linux"))]
 #[test]
 fn test_abstract_stream_iter() {
-    let addr = or_panic!(SocketAddr::from_abstract_namespace(b"hidden"));
+    let addr = or_panic!(SocketAddr::from_abstract_name(b"hidden"));
     let listener = or_panic!(UnixListener::bind_addr(&addr));
 
     let thread = thread::spawn(move || {
@@ -454,13 +460,13 @@ fn test_abstract_stream_iter() {
 #[cfg(any(target_os = "android", target_os = "linux"))]
 #[test]
 fn test_abstract_datagram_bind_send_to_addr() {
-    let addr1 = or_panic!(SocketAddr::from_abstract_namespace(b"ns1"));
+    let addr1 = or_panic!(SocketAddr::from_abstract_name(b"ns1"));
     let sock1 = or_panic!(UnixDatagram::bind_addr(&addr1));
 
     let local = or_panic!(sock1.local_addr());
-    assert_eq!(local.as_abstract_namespace().unwrap(), b"ns1");
+    assert_eq!(local.as_abstract_name().unwrap(), b"ns1");
 
-    let addr2 = or_panic!(SocketAddr::from_abstract_namespace(b"ns2"));
+    let addr2 = or_panic!(SocketAddr::from_abstract_name(b"ns2"));
     let sock2 = or_panic!(UnixDatagram::bind_addr(&addr2));
 
     let msg = b"hello world";
@@ -469,13 +475,13 @@ fn test_abstract_datagram_bind_send_to_addr() {
     let (len, addr) = or_panic!(sock2.recv_from(&mut buf));
     assert_eq!(msg, &buf[..]);
     assert_eq!(len, 11);
-    assert_eq!(addr.as_abstract_namespace().unwrap(), b"ns1");
+    assert_eq!(addr.as_abstract_name().unwrap(), b"ns1");
 }
 
 #[cfg(any(target_os = "android", target_os = "linux"))]
 #[test]
 fn test_abstract_datagram_connect_addr() {
-    let addr1 = or_panic!(SocketAddr::from_abstract_namespace(b"ns3"));
+    let addr1 = or_panic!(SocketAddr::from_abstract_name(b"ns3"));
     let bsock1 = or_panic!(UnixDatagram::bind_addr(&addr1));
 
     let sock = or_panic!(UnixDatagram::unbound());
@@ -489,7 +495,7 @@ fn test_abstract_datagram_connect_addr() {
     assert_eq!(addr.is_unnamed(), true);
     assert_eq!(msg, &buf[..]);
 
-    let addr2 = or_panic!(SocketAddr::from_abstract_namespace(b"ns4"));
+    let addr2 = or_panic!(SocketAddr::from_abstract_name(b"ns4"));
     let bsock2 = or_panic!(UnixDatagram::bind_addr(&addr2));
 
     or_panic!(sock.connect_addr(&addr2));
@@ -499,8 +505,8 @@ fn test_abstract_datagram_connect_addr() {
 
 #[cfg(any(target_os = "android", target_os = "linux"))]
 #[test]
-fn test_abstract_namespace_too_long() {
-    match SocketAddr::from_abstract_namespace(
+fn test_abstract_name_too_long() {
+    match SocketAddr::from_abstract_name(
         b"abcdefghijklmnopqrstuvwxyzabcdefghijklmn\
         opqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghi\
         jklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz",
@@ -513,11 +519,11 @@ fn test_abstract_namespace_too_long() {
 
 #[cfg(any(target_os = "android", target_os = "linux"))]
 #[test]
-fn test_abstract_namespace_no_pathname_and_not_unnamed() {
-    let namespace = b"local";
-    let addr = or_panic!(SocketAddr::from_abstract_namespace(&namespace[..]));
+fn test_abstract_no_pathname_and_not_unnamed() {
+    let name = b"local";
+    let addr = or_panic!(SocketAddr::from_abstract_name(name));
     assert_eq!(addr.as_pathname(), None);
-    assert_eq!(addr.as_abstract_namespace(), Some(&namespace[..]));
+    assert_eq!(addr.as_abstract_name(), Some(&name[..]));
     assert_eq!(addr.is_unnamed(), false);
 }
 
diff --git a/library/std/src/os/wasi/io/mod.rs b/library/std/src/os/wasi/io/mod.rs
index 57bd842a50ce..4e123a1eec8a 100644
--- a/library/std/src/os/wasi/io/mod.rs
+++ b/library/std/src/os/wasi/io/mod.rs
@@ -1,6 +1,6 @@
 //! WASI-specific extensions to general I/O primitives.
 
-#![stable(feature = "io_safety", since = "1.63.0")]
+#![stable(feature = "io_safety_wasi", since = "1.65.0")]
 
-#[stable(feature = "io_safety", since = "1.63.0")]
+#[stable(feature = "io_safety_wasi", since = "1.65.0")]
 pub use crate::os::fd::*;
diff --git a/library/std/src/path.rs b/library/std/src/path.rs
index 9d63281627d6..af88b9070c18 100644
--- a/library/std/src/path.rs
+++ b/library/std/src/path.rs
@@ -2142,7 +2142,10 @@ impl Path {
 
     /// Returns the `Path` without its final component, if there is one.
     ///
-    /// Returns [`None`] if the path terminates in a root or prefix.
+    /// This means it returns `Some("")` for relative paths with one component.
+    ///
+    /// Returns [`None`] if the path terminates in a root or prefix, or if it's
+    /// the empty string.
     ///
     /// # Examples
     ///
@@ -2156,6 +2159,14 @@ impl Path {
     /// let grand_parent = parent.parent().unwrap();
     /// assert_eq!(grand_parent, Path::new("/"));
     /// assert_eq!(grand_parent.parent(), None);
+    ///
+    /// let relative_path = Path::new("foo/bar");
+    /// let parent = relative_path.parent();
+    /// assert_eq!(parent, Some(Path::new("foo")));
+    /// let grand_parent = parent.and_then(Path::parent);
+    /// assert_eq!(grand_parent, Some(Path::new("")));
+    /// let great_grand_parent = grand_parent.and_then(Path::parent);
+    /// assert_eq!(great_grand_parent, None);
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     #[doc(alias = "dirname")]
diff --git a/library/std/src/personality/gcc.rs b/library/std/src/personality/gcc.rs
index 7f0b0439cf08..5fc1b91a1c35 100644
--- a/library/std/src/personality/gcc.rs
+++ b/library/std/src/personality/gcc.rs
@@ -219,7 +219,7 @@ cfg_if::cfg_if! {
         }
 
         cfg_if::cfg_if! {
-            if #[cfg(all(windows, target_arch = "x86_64", target_env = "gnu"))] {
+            if #[cfg(all(windows, any(target_arch = "aarch64", target_arch = "x86_64"), target_env = "gnu"))] {
                 // On x86_64 MinGW targets, the unwinding mechanism is SEH however the unwind
                 // handler data (aka LSDA) uses GCC-compatible encoding.
                 #[lang = "eh_personality"]
diff --git a/library/std/src/prelude/v1.rs b/library/std/src/prelude/v1.rs
index 0226c4d7a258..d5ac16e6b94e 100644
--- a/library/std/src/prelude/v1.rs
+++ b/library/std/src/prelude/v1.rs
@@ -59,9 +59,16 @@ pub use core::prelude::v1::{RustcDecodable, RustcEncodable};
 
 // Do not `doc(no_inline)` so that they become doc items on their own
 // (no public module for them to be re-exported from).
+#[cfg(not(bootstrap))]
+#[stable(feature = "builtin_macro_prelude", since = "1.38.0")]
+pub use core::prelude::v1::alloc_error_handler;
 #[stable(feature = "builtin_macro_prelude", since = "1.38.0")]
 pub use core::prelude::v1::{bench, derive, global_allocator, test, test_case};
 
+#[unstable(feature = "derive_const", issue = "none")]
+#[cfg(not(bootstrap))]
+pub use core::prelude::v1::derive_const;
+
 // Do not `doc(no_inline)` either.
 #[unstable(
     feature = "cfg_accessible",
diff --git a/library/std/src/sync/condvar.rs b/library/std/src/sync/condvar.rs
index eb1e7135a6e4..76a1b4a2a86c 100644
--- a/library/std/src/sync/condvar.rs
+++ b/library/std/src/sync/condvar.rs
@@ -3,7 +3,7 @@ mod tests;
 
 use crate::fmt;
 use crate::sync::{mutex, poison, LockResult, MutexGuard, PoisonError};
-use crate::sys_common::condvar as sys;
+use crate::sys::locks as sys;
 use crate::time::{Duration, Instant};
 
 /// A type indicating whether a timed wait on a condition variable returned
diff --git a/library/std/src/sync/mod.rs b/library/std/src/sync/mod.rs
index 7b507a169b39..4fee8d3e92fc 100644
--- a/library/std/src/sync/mod.rs
+++ b/library/std/src/sync/mod.rs
@@ -182,6 +182,7 @@ pub mod mpsc;
 mod barrier;
 mod condvar;
 mod lazy_lock;
+mod mpmc;
 mod mutex;
 mod once;
 mod once_lock;
diff --git a/library/std/src/sync/mpmc/array.rs b/library/std/src/sync/mpmc/array.rs
new file mode 100644
index 000000000000..4db7b4990b97
--- /dev/null
+++ b/library/std/src/sync/mpmc/array.rs
@@ -0,0 +1,513 @@
+//! Bounded channel based on a preallocated array.
+//!
+//! This flavor has a fixed, positive capacity.
+//!
+//! The implementation is based on Dmitry Vyukov's bounded MPMC queue.
+//!
+//! Source:
+//!   - <http://www.1024cores.net/home/lock-free-algorithms/queues/bounded-mpmc-queue>
+//!   - <https://docs.google.com/document/d/1yIAYmbvL3JxOKOjuCyon7JhW4cSv1wy5hC0ApeGMV9s/pub>
+
+use super::context::Context;
+use super::error::*;
+use super::select::{Operation, Selected, Token};
+use super::utils::{Backoff, CachePadded};
+use super::waker::SyncWaker;
+
+use crate::cell::UnsafeCell;
+use crate::mem::MaybeUninit;
+use crate::ptr;
+use crate::sync::atomic::{self, AtomicUsize, Ordering};
+use crate::time::Instant;
+
+/// A slot in a channel.
+struct Slot<T> {
+    /// The current stamp.
+    stamp: AtomicUsize,
+
+    /// The message in this slot.
+    msg: UnsafeCell<MaybeUninit<T>>,
+}
+
+/// The token type for the array flavor.
+#[derive(Debug)]
+pub(crate) struct ArrayToken {
+    /// Slot to read from or write to.
+    slot: *const u8,
+
+    /// Stamp to store into the slot after reading or writing.
+    stamp: usize,
+}
+
+impl Default for ArrayToken {
+    #[inline]
+    fn default() -> Self {
+        ArrayToken { slot: ptr::null(), stamp: 0 }
+    }
+}
+
+/// Bounded channel based on a preallocated array.
+pub(crate) struct Channel<T> {
+    /// The head of the channel.
+    ///
+    /// This value is a "stamp" consisting of an index into the buffer, a mark bit, and a lap, but
+    /// packed into a single `usize`. The lower bits represent the index, while the upper bits
+    /// represent the lap. The mark bit in the head is always zero.
+    ///
+    /// Messages are popped from the head of the channel.
+    head: CachePadded<AtomicUsize>,
+
+    /// The tail of the channel.
+    ///
+    /// This value is a "stamp" consisting of an index into the buffer, a mark bit, and a lap, but
+    /// packed into a single `usize`. The lower bits represent the index, while the upper bits
+    /// represent the lap. The mark bit indicates that the channel is disconnected.
+    ///
+    /// Messages are pushed into the tail of the channel.
+    tail: CachePadded<AtomicUsize>,
+
+    /// The buffer holding slots.
+    buffer: Box<[Slot<T>]>,
+
+    /// The channel capacity.
+    cap: usize,
+
+    /// A stamp with the value of `{ lap: 1, mark: 0, index: 0 }`.
+    one_lap: usize,
+
+    /// If this bit is set in the tail, that means the channel is disconnected.
+    mark_bit: usize,
+
+    /// Senders waiting while the channel is full.
+    senders: SyncWaker,
+
+    /// Receivers waiting while the channel is empty and not disconnected.
+    receivers: SyncWaker,
+}
+
+impl<T> Channel<T> {
+    /// Creates a bounded channel of capacity `cap`.
+    pub(crate) fn with_capacity(cap: usize) -> Self {
+        assert!(cap > 0, "capacity must be positive");
+
+        // Compute constants `mark_bit` and `one_lap`.
+        let mark_bit = (cap + 1).next_power_of_two();
+        let one_lap = mark_bit * 2;
+
+        // Head is initialized to `{ lap: 0, mark: 0, index: 0 }`.
+        let head = 0;
+        // Tail is initialized to `{ lap: 0, mark: 0, index: 0 }`.
+        let tail = 0;
+
+        // Allocate a buffer of `cap` slots initialized
+        // with stamps.
+        let buffer: Box<[Slot<T>]> = (0..cap)
+            .map(|i| {
+                // Set the stamp to `{ lap: 0, mark: 0, index: i }`.
+                Slot { stamp: AtomicUsize::new(i), msg: UnsafeCell::new(MaybeUninit::uninit()) }
+            })
+            .collect();
+
+        Channel {
+            buffer,
+            cap,
+            one_lap,
+            mark_bit,
+            head: CachePadded::new(AtomicUsize::new(head)),
+            tail: CachePadded::new(AtomicUsize::new(tail)),
+            senders: SyncWaker::new(),
+            receivers: SyncWaker::new(),
+        }
+    }
+
+    /// Attempts to reserve a slot for sending a message.
+    fn start_send(&self, token: &mut Token) -> bool {
+        let backoff = Backoff::new();
+        let mut tail = self.tail.load(Ordering::Relaxed);
+
+        loop {
+            // Check if the channel is disconnected.
+            if tail & self.mark_bit != 0 {
+                token.array.slot = ptr::null();
+                token.array.stamp = 0;
+                return true;
+            }
+
+            // Deconstruct the tail.
+            let index = tail & (self.mark_bit - 1);
+            let lap = tail & !(self.one_lap - 1);
+
+            // Inspect the corresponding slot.
+            debug_assert!(index < self.buffer.len());
+            let slot = unsafe { self.buffer.get_unchecked(index) };
+            let stamp = slot.stamp.load(Ordering::Acquire);
+
+            // If the tail and the stamp match, we may attempt to push.
+            if tail == stamp {
+                let new_tail = if index + 1 < self.cap {
+                    // Same lap, incremented index.
+                    // Set to `{ lap: lap, mark: 0, index: index + 1 }`.
+                    tail + 1
+                } else {
+                    // One lap forward, index wraps around to zero.
+                    // Set to `{ lap: lap.wrapping_add(1), mark: 0, index: 0 }`.
+                    lap.wrapping_add(self.one_lap)
+                };
+
+                // Try moving the tail.
+                match self.tail.compare_exchange_weak(
+                    tail,
+                    new_tail,
+                    Ordering::SeqCst,
+                    Ordering::Relaxed,
+                ) {
+                    Ok(_) => {
+                        // Prepare the token for the follow-up call to `write`.
+                        token.array.slot = slot as *const Slot<T> as *const u8;
+                        token.array.stamp = tail + 1;
+                        return true;
+                    }
+                    Err(_) => {
+                        backoff.spin();
+                        tail = self.tail.load(Ordering::Relaxed);
+                    }
+                }
+            } else if stamp.wrapping_add(self.one_lap) == tail + 1 {
+                atomic::fence(Ordering::SeqCst);
+                let head = self.head.load(Ordering::Relaxed);
+
+                // If the head lags one lap behind the tail as well...
+                if head.wrapping_add(self.one_lap) == tail {
+                    // ...then the channel is full.
+                    return false;
+                }
+
+                backoff.spin();
+                tail = self.tail.load(Ordering::Relaxed);
+            } else {
+                // Snooze because we need to wait for the stamp to get updated.
+                backoff.snooze();
+                tail = self.tail.load(Ordering::Relaxed);
+            }
+        }
+    }
+
+    /// Writes a message into the channel.
+    pub(crate) unsafe fn write(&self, token: &mut Token, msg: T) -> Result<(), T> {
+        // If there is no slot, the channel is disconnected.
+        if token.array.slot.is_null() {
+            return Err(msg);
+        }
+
+        let slot: &Slot<T> = &*(token.array.slot as *const Slot<T>);
+
+        // Write the message into the slot and update the stamp.
+        slot.msg.get().write(MaybeUninit::new(msg));
+        slot.stamp.store(token.array.stamp, Ordering::Release);
+
+        // Wake a sleeping receiver.
+        self.receivers.notify();
+        Ok(())
+    }
+
+    /// Attempts to reserve a slot for receiving a message.
+    fn start_recv(&self, token: &mut Token) -> bool {
+        let backoff = Backoff::new();
+        let mut head = self.head.load(Ordering::Relaxed);
+
+        loop {
+            // Deconstruct the head.
+            let index = head & (self.mark_bit - 1);
+            let lap = head & !(self.one_lap - 1);
+
+            // Inspect the corresponding slot.
+            debug_assert!(index < self.buffer.len());
+            let slot = unsafe { self.buffer.get_unchecked(index) };
+            let stamp = slot.stamp.load(Ordering::Acquire);
+
+            // If the the stamp is ahead of the head by 1, we may attempt to pop.
+            if head + 1 == stamp {
+                let new = if index + 1 < self.cap {
+                    // Same lap, incremented index.
+                    // Set to `{ lap: lap, mark: 0, index: index + 1 }`.
+                    head + 1
+                } else {
+                    // One lap forward, index wraps around to zero.
+                    // Set to `{ lap: lap.wrapping_add(1), mark: 0, index: 0 }`.
+                    lap.wrapping_add(self.one_lap)
+                };
+
+                // Try moving the head.
+                match self.head.compare_exchange_weak(
+                    head,
+                    new,
+                    Ordering::SeqCst,
+                    Ordering::Relaxed,
+                ) {
+                    Ok(_) => {
+                        // Prepare the token for the follow-up call to `read`.
+                        token.array.slot = slot as *const Slot<T> as *const u8;
+                        token.array.stamp = head.wrapping_add(self.one_lap);
+                        return true;
+                    }
+                    Err(_) => {
+                        backoff.spin();
+                        head = self.head.load(Ordering::Relaxed);
+                    }
+                }
+            } else if stamp == head {
+                atomic::fence(Ordering::SeqCst);
+                let tail = self.tail.load(Ordering::Relaxed);
+
+                // If the tail equals the head, that means the channel is empty.
+                if (tail & !self.mark_bit) == head {
+                    // If the channel is disconnected...
+                    if tail & self.mark_bit != 0 {
+                        // ...then receive an error.
+                        token.array.slot = ptr::null();
+                        token.array.stamp = 0;
+                        return true;
+                    } else {
+                        // Otherwise, the receive operation is not ready.
+                        return false;
+                    }
+                }
+
+                backoff.spin();
+                head = self.head.load(Ordering::Relaxed);
+            } else {
+                // Snooze because we need to wait for the stamp to get updated.
+                backoff.snooze();
+                head = self.head.load(Ordering::Relaxed);
+            }
+        }
+    }
+
+    /// Reads a message from the channel.
+    pub(crate) unsafe fn read(&self, token: &mut Token) -> Result<T, ()> {
+        if token.array.slot.is_null() {
+            // The channel is disconnected.
+            return Err(());
+        }
+
+        let slot: &Slot<T> = &*(token.array.slot as *const Slot<T>);
+
+        // Read the message from the slot and update the stamp.
+        let msg = slot.msg.get().read().assume_init();
+        slot.stamp.store(token.array.stamp, Ordering::Release);
+
+        // Wake a sleeping sender.
+        self.senders.notify();
+        Ok(msg)
+    }
+
+    /// Attempts to send a message into the channel.
+    pub(crate) fn try_send(&self, msg: T) -> Result<(), TrySendError<T>> {
+        let token = &mut Token::default();
+        if self.start_send(token) {
+            unsafe { self.write(token, msg).map_err(TrySendError::Disconnected) }
+        } else {
+            Err(TrySendError::Full(msg))
+        }
+    }
+
+    /// Sends a message into the channel.
+    pub(crate) fn send(
+        &self,
+        msg: T,
+        deadline: Option<Instant>,
+    ) -> Result<(), SendTimeoutError<T>> {
+        let token = &mut Token::default();
+        loop {
+            // Try sending a message several times.
+            let backoff = Backoff::new();
+            loop {
+                if self.start_send(token) {
+                    let res = unsafe { self.write(token, msg) };
+                    return res.map_err(SendTimeoutError::Disconnected);
+                }
+
+                if backoff.is_completed() {
+                    break;
+                } else {
+                    backoff.spin();
+                }
+            }
+
+            if let Some(d) = deadline {
+                if Instant::now() >= d {
+                    return Err(SendTimeoutError::Timeout(msg));
+                }
+            }
+
+            Context::with(|cx| {
+                // Prepare for blocking until a receiver wakes us up.
+                let oper = Operation::hook(token);
+                self.senders.register(oper, cx);
+
+                // Has the channel become ready just now?
+                if !self.is_full() || self.is_disconnected() {
+                    let _ = cx.try_select(Selected::Aborted);
+                }
+
+                // Block the current thread.
+                let sel = cx.wait_until(deadline);
+
+                match sel {
+                    Selected::Waiting => unreachable!(),
+                    Selected::Aborted | Selected::Disconnected => {
+                        self.senders.unregister(oper).unwrap();
+                    }
+                    Selected::Operation(_) => {}
+                }
+            });
+        }
+    }
+
+    /// Attempts to receive a message without blocking.
+    pub(crate) fn try_recv(&self) -> Result<T, TryRecvError> {
+        let token = &mut Token::default();
+
+        if self.start_recv(token) {
+            unsafe { self.read(token).map_err(|_| TryRecvError::Disconnected) }
+        } else {
+            Err(TryRecvError::Empty)
+        }
+    }
+
+    /// Receives a message from the channel.
+    pub(crate) fn recv(&self, deadline: Option<Instant>) -> Result<T, RecvTimeoutError> {
+        let token = &mut Token::default();
+        loop {
+            if self.start_recv(token) {
+                let res = unsafe { self.read(token) };
+                return res.map_err(|_| RecvTimeoutError::Disconnected);
+            }
+
+            if let Some(d) = deadline {
+                if Instant::now() >= d {
+                    return Err(RecvTimeoutError::Timeout);
+                }
+            }
+
+            Context::with(|cx| {
+                // Prepare for blocking until a sender wakes us up.
+                let oper = Operation::hook(token);
+                self.receivers.register(oper, cx);
+
+                // Has the channel become ready just now?
+                if !self.is_empty() || self.is_disconnected() {
+                    let _ = cx.try_select(Selected::Aborted);
+                }
+
+                // Block the current thread.
+                let sel = cx.wait_until(deadline);
+
+                match sel {
+                    Selected::Waiting => unreachable!(),
+                    Selected::Aborted | Selected::Disconnected => {
+                        self.receivers.unregister(oper).unwrap();
+                        // If the channel was disconnected, we still have to check for remaining
+                        // messages.
+                    }
+                    Selected::Operation(_) => {}
+                }
+            });
+        }
+    }
+
+    /// Returns the current number of messages inside the channel.
+    pub(crate) fn len(&self) -> usize {
+        loop {
+            // Load the tail, then load the head.
+            let tail = self.tail.load(Ordering::SeqCst);
+            let head = self.head.load(Ordering::SeqCst);
+
+            // If the tail didn't change, we've got consistent values to work with.
+            if self.tail.load(Ordering::SeqCst) == tail {
+                let hix = head & (self.mark_bit - 1);
+                let tix = tail & (self.mark_bit - 1);
+
+                return if hix < tix {
+                    tix - hix
+                } else if hix > tix {
+                    self.cap - hix + tix
+                } else if (tail & !self.mark_bit) == head {
+                    0
+                } else {
+                    self.cap
+                };
+            }
+        }
+    }
+
+    /// Returns the capacity of the channel.
+    #[allow(clippy::unnecessary_wraps)] // This is intentional.
+    pub(crate) fn capacity(&self) -> Option<usize> {
+        Some(self.cap)
+    }
+
+    /// Disconnects the channel and wakes up all blocked senders and receivers.
+    ///
+    /// Returns `true` if this call disconnected the channel.
+    pub(crate) fn disconnect(&self) -> bool {
+        let tail = self.tail.fetch_or(self.mark_bit, Ordering::SeqCst);
+
+        if tail & self.mark_bit == 0 {
+            self.senders.disconnect();
+            self.receivers.disconnect();
+            true
+        } else {
+            false
+        }
+    }
+
+    /// Returns `true` if the channel is disconnected.
+    pub(crate) fn is_disconnected(&self) -> bool {
+        self.tail.load(Ordering::SeqCst) & self.mark_bit != 0
+    }
+
+    /// Returns `true` if the channel is empty.
+    pub(crate) fn is_empty(&self) -> bool {
+        let head = self.head.load(Ordering::SeqCst);
+        let tail = self.tail.load(Ordering::SeqCst);
+
+        // Is the tail equal to the head?
+        //
+        // Note: If the head changes just before we load the tail, that means there was a moment
+        // when the channel was not empty, so it is safe to just return `false`.
+        (tail & !self.mark_bit) == head
+    }
+
+    /// Returns `true` if the channel is full.
+    pub(crate) fn is_full(&self) -> bool {
+        let tail = self.tail.load(Ordering::SeqCst);
+        let head = self.head.load(Ordering::SeqCst);
+
+        // Is the head lagging one lap behind tail?
+        //
+        // Note: If the tail changes just before we load the head, that means there was a moment
+        // when the channel was not full, so it is safe to just return `false`.
+        head.wrapping_add(self.one_lap) == tail & !self.mark_bit
+    }
+}
+
+impl<T> Drop for Channel<T> {
+    fn drop(&mut self) {
+        // Get the index of the head.
+        let hix = self.head.load(Ordering::Relaxed) & (self.mark_bit - 1);
+
+        // Loop over all slots that hold a message and drop them.
+        for i in 0..self.len() {
+            // Compute the index of the next slot holding a message.
+            let index = if hix + i < self.cap { hix + i } else { hix + i - self.cap };
+
+            unsafe {
+                debug_assert!(index < self.buffer.len());
+                let slot = self.buffer.get_unchecked_mut(index);
+                let msg = &mut *slot.msg.get();
+                msg.as_mut_ptr().drop_in_place();
+            }
+        }
+    }
+}
diff --git a/library/std/src/sync/mpmc/context.rs b/library/std/src/sync/mpmc/context.rs
new file mode 100644
index 000000000000..bbfc6ce00ffc
--- /dev/null
+++ b/library/std/src/sync/mpmc/context.rs
@@ -0,0 +1,155 @@
+//! Thread-local channel context.
+
+use super::select::Selected;
+use super::waker::current_thread_id;
+
+use crate::cell::Cell;
+use crate::ptr;
+use crate::sync::atomic::{AtomicPtr, AtomicUsize, Ordering};
+use crate::sync::Arc;
+use crate::thread::{self, Thread};
+use crate::time::Instant;
+
+/// Thread-local context.
+#[derive(Debug, Clone)]
+pub struct Context {
+    inner: Arc<Inner>,
+}
+
+/// Inner representation of `Context`.
+#[derive(Debug)]
+struct Inner {
+    /// Selected operation.
+    select: AtomicUsize,
+
+    /// A slot into which another thread may store a pointer to its `Packet`.
+    packet: AtomicPtr<()>,
+
+    /// Thread handle.
+    thread: Thread,
+
+    /// Thread id.
+    thread_id: usize,
+}
+
+impl Context {
+    /// Creates a new context for the duration of the closure.
+    #[inline]
+    pub fn with<F, R>(f: F) -> R
+    where
+        F: FnOnce(&Context) -> R,
+    {
+        thread_local! {
+            /// Cached thread-local context.
+            static CONTEXT: Cell<Option<Context>> = Cell::new(Some(Context::new()));
+        }
+
+        let mut f = Some(f);
+        let mut f = |cx: &Context| -> R {
+            let f = f.take().unwrap();
+            f(cx)
+        };
+
+        CONTEXT
+            .try_with(|cell| match cell.take() {
+                None => f(&Context::new()),
+                Some(cx) => {
+                    cx.reset();
+                    let res = f(&cx);
+                    cell.set(Some(cx));
+                    res
+                }
+            })
+            .unwrap_or_else(|_| f(&Context::new()))
+    }
+
+    /// Creates a new `Context`.
+    #[cold]
+    fn new() -> Context {
+        Context {
+            inner: Arc::new(Inner {
+                select: AtomicUsize::new(Selected::Waiting.into()),
+                packet: AtomicPtr::new(ptr::null_mut()),
+                thread: thread::current(),
+                thread_id: current_thread_id(),
+            }),
+        }
+    }
+
+    /// Resets `select` and `packet`.
+    #[inline]
+    fn reset(&self) {
+        self.inner.select.store(Selected::Waiting.into(), Ordering::Release);
+        self.inner.packet.store(ptr::null_mut(), Ordering::Release);
+    }
+
+    /// Attempts to select an operation.
+    ///
+    /// On failure, the previously selected operation is returned.
+    #[inline]
+    pub fn try_select(&self, select: Selected) -> Result<(), Selected> {
+        self.inner
+            .select
+            .compare_exchange(
+                Selected::Waiting.into(),
+                select.into(),
+                Ordering::AcqRel,
+                Ordering::Acquire,
+            )
+            .map(|_| ())
+            .map_err(|e| e.into())
+    }
+
+    /// Stores a packet.
+    ///
+    /// This method must be called after `try_select` succeeds and there is a packet to provide.
+    #[inline]
+    pub fn store_packet(&self, packet: *mut ()) {
+        if !packet.is_null() {
+            self.inner.packet.store(packet, Ordering::Release);
+        }
+    }
+
+    /// Waits until an operation is selected and returns it.
+    ///
+    /// If the deadline is reached, `Selected::Aborted` will be selected.
+    #[inline]
+    pub fn wait_until(&self, deadline: Option<Instant>) -> Selected {
+        loop {
+            // Check whether an operation has been selected.
+            let sel = Selected::from(self.inner.select.load(Ordering::Acquire));
+            if sel != Selected::Waiting {
+                return sel;
+            }
+
+            // If there's a deadline, park the current thread until the deadline is reached.
+            if let Some(end) = deadline {
+                let now = Instant::now();
+
+                if now < end {
+                    thread::park_timeout(end - now);
+                } else {
+                    // The deadline has been reached. Try aborting select.
+                    return match self.try_select(Selected::Aborted) {
+                        Ok(()) => Selected::Aborted,
+                        Err(s) => s,
+                    };
+                }
+            } else {
+                thread::park();
+            }
+        }
+    }
+
+    /// Unparks the thread this context belongs to.
+    #[inline]
+    pub fn unpark(&self) {
+        self.inner.thread.unpark();
+    }
+
+    /// Returns the id of the thread this context belongs to.
+    #[inline]
+    pub fn thread_id(&self) -> usize {
+        self.inner.thread_id
+    }
+}
diff --git a/library/std/src/sync/mpmc/counter.rs b/library/std/src/sync/mpmc/counter.rs
new file mode 100644
index 000000000000..a5a6bdc67f13
--- /dev/null
+++ b/library/std/src/sync/mpmc/counter.rs
@@ -0,0 +1,137 @@
+use crate::ops;
+use crate::process;
+use crate::sync::atomic::{AtomicBool, AtomicUsize, Ordering};
+
+/// Reference counter internals.
+struct Counter<C> {
+    /// The number of senders associated with the channel.
+    senders: AtomicUsize,
+
+    /// The number of receivers associated with the channel.
+    receivers: AtomicUsize,
+
+    /// Set to `true` if the last sender or the last receiver reference deallocates the channel.
+    destroy: AtomicBool,
+
+    /// The internal channel.
+    chan: C,
+}
+
+/// Wraps a channel into the reference counter.
+pub(crate) fn new<C>(chan: C) -> (Sender<C>, Receiver<C>) {
+    let counter = Box::into_raw(Box::new(Counter {
+        senders: AtomicUsize::new(1),
+        receivers: AtomicUsize::new(1),
+        destroy: AtomicBool::new(false),
+        chan,
+    }));
+    let s = Sender { counter };
+    let r = Receiver { counter };
+    (s, r)
+}
+
+/// The sending side.
+pub(crate) struct Sender<C> {
+    counter: *mut Counter<C>,
+}
+
+impl<C> Sender<C> {
+    /// Returns the internal `Counter`.
+    fn counter(&self) -> &Counter<C> {
+        unsafe { &*self.counter }
+    }
+
+    /// Acquires another sender reference.
+    pub(crate) fn acquire(&self) -> Sender<C> {
+        let count = self.counter().senders.fetch_add(1, Ordering::Relaxed);
+
+        // Cloning senders and calling `mem::forget` on the clones could potentially overflow the
+        // counter. It's very difficult to recover sensibly from such degenerate scenarios so we
+        // just abort when the count becomes very large.
+        if count > isize::MAX as usize {
+            process::abort();
+        }
+
+        Sender { counter: self.counter }
+    }
+
+    /// Releases the sender reference.
+    ///
+    /// Function `disconnect` will be called if this is the last sender reference.
+    pub(crate) unsafe fn release<F: FnOnce(&C) -> bool>(&self, disconnect: F) {
+        if self.counter().senders.fetch_sub(1, Ordering::AcqRel) == 1 {
+            disconnect(&self.counter().chan);
+
+            if self.counter().destroy.swap(true, Ordering::AcqRel) {
+                drop(Box::from_raw(self.counter));
+            }
+        }
+    }
+}
+
+impl<C> ops::Deref for Sender<C> {
+    type Target = C;
+
+    fn deref(&self) -> &C {
+        &self.counter().chan
+    }
+}
+
+impl<C> PartialEq for Sender<C> {
+    fn eq(&self, other: &Sender<C>) -> bool {
+        self.counter == other.counter
+    }
+}
+
+/// The receiving side.
+pub(crate) struct Receiver<C> {
+    counter: *mut Counter<C>,
+}
+
+impl<C> Receiver<C> {
+    /// Returns the internal `Counter`.
+    fn counter(&self) -> &Counter<C> {
+        unsafe { &*self.counter }
+    }
+
+    /// Acquires another receiver reference.
+    pub(crate) fn acquire(&self) -> Receiver<C> {
+        let count = self.counter().receivers.fetch_add(1, Ordering::Relaxed);
+
+        // Cloning receivers and calling `mem::forget` on the clones could potentially overflow the
+        // counter. It's very difficult to recover sensibly from such degenerate scenarios so we
+        // just abort when the count becomes very large.
+        if count > isize::MAX as usize {
+            process::abort();
+        }
+
+        Receiver { counter: self.counter }
+    }
+
+    /// Releases the receiver reference.
+    ///
+    /// Function `disconnect` will be called if this is the last receiver reference.
+    pub(crate) unsafe fn release<F: FnOnce(&C) -> bool>(&self, disconnect: F) {
+        if self.counter().receivers.fetch_sub(1, Ordering::AcqRel) == 1 {
+            disconnect(&self.counter().chan);
+
+            if self.counter().destroy.swap(true, Ordering::AcqRel) {
+                drop(Box::from_raw(self.counter));
+            }
+        }
+    }
+}
+
+impl<C> ops::Deref for Receiver<C> {
+    type Target = C;
+
+    fn deref(&self) -> &C {
+        &self.counter().chan
+    }
+}
+
+impl<C> PartialEq for Receiver<C> {
+    fn eq(&self, other: &Receiver<C>) -> bool {
+        self.counter == other.counter
+    }
+}
diff --git a/library/std/src/sync/mpmc/error.rs b/library/std/src/sync/mpmc/error.rs
new file mode 100644
index 000000000000..1b8a1f387974
--- /dev/null
+++ b/library/std/src/sync/mpmc/error.rs
@@ -0,0 +1,46 @@
+use crate::error;
+use crate::fmt;
+
+pub use crate::sync::mpsc::{RecvError, RecvTimeoutError, SendError, TryRecvError, TrySendError};
+
+/// An error returned from the [`send_timeout`] method.
+///
+/// The error contains the message being sent so it can be recovered.
+///
+/// [`send_timeout`]: super::Sender::send_timeout
+#[derive(PartialEq, Eq, Clone, Copy)]
+pub enum SendTimeoutError<T> {
+    /// The message could not be sent because the channel is full and the operation timed out.
+    ///
+    /// If this is a zero-capacity channel, then the error indicates that there was no receiver
+    /// available to receive the message and the operation timed out.
+    Timeout(T),
+
+    /// The message could not be sent because the channel is disconnected.
+    Disconnected(T),
+}
+
+impl<T> fmt::Debug for SendTimeoutError<T> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        "SendTimeoutError(..)".fmt(f)
+    }
+}
+
+impl<T> fmt::Display for SendTimeoutError<T> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match *self {
+            SendTimeoutError::Timeout(..) => "timed out waiting on send operation".fmt(f),
+            SendTimeoutError::Disconnected(..) => "sending on a disconnected channel".fmt(f),
+        }
+    }
+}
+
+impl<T: Send> error::Error for SendTimeoutError<T> {}
+
+impl<T> From<SendError<T>> for SendTimeoutError<T> {
+    fn from(err: SendError<T>) -> SendTimeoutError<T> {
+        match err {
+            SendError(e) => SendTimeoutError::Disconnected(e),
+        }
+    }
+}
diff --git a/library/std/src/sync/mpmc/list.rs b/library/std/src/sync/mpmc/list.rs
new file mode 100644
index 000000000000..2d5b2fb3b231
--- /dev/null
+++ b/library/std/src/sync/mpmc/list.rs
@@ -0,0 +1,638 @@
+//! Unbounded channel implemented as a linked list.
+
+use super::context::Context;
+use super::error::*;
+use super::select::{Operation, Selected, Token};
+use super::utils::{Backoff, CachePadded};
+use super::waker::SyncWaker;
+
+use crate::cell::UnsafeCell;
+use crate::marker::PhantomData;
+use crate::mem::MaybeUninit;
+use crate::ptr;
+use crate::sync::atomic::{self, AtomicPtr, AtomicUsize, Ordering};
+use crate::time::Instant;
+
+// Bits indicating the state of a slot:
+// * If a message has been written into the slot, `WRITE` is set.
+// * If a message has been read from the slot, `READ` is set.
+// * If the block is being destroyed, `DESTROY` is set.
+const WRITE: usize = 1;
+const READ: usize = 2;
+const DESTROY: usize = 4;
+
+// Each block covers one "lap" of indices.
+const LAP: usize = 32;
+// The maximum number of messages a block can hold.
+const BLOCK_CAP: usize = LAP - 1;
+// How many lower bits are reserved for metadata.
+const SHIFT: usize = 1;
+// Has two different purposes:
+// * If set in head, indicates that the block is not the last one.
+// * If set in tail, indicates that the channel is disconnected.
+const MARK_BIT: usize = 1;
+
+/// A slot in a block.
+struct Slot<T> {
+    /// The message.
+    msg: UnsafeCell<MaybeUninit<T>>,
+
+    /// The state of the slot.
+    state: AtomicUsize,
+}
+
+impl<T> Slot<T> {
+    /// Waits until a message is written into the slot.
+    fn wait_write(&self) {
+        let backoff = Backoff::new();
+        while self.state.load(Ordering::Acquire) & WRITE == 0 {
+            backoff.snooze();
+        }
+    }
+}
+
+/// A block in a linked list.
+///
+/// Each block in the list can hold up to `BLOCK_CAP` messages.
+struct Block<T> {
+    /// The next block in the linked list.
+    next: AtomicPtr<Block<T>>,
+
+    /// Slots for messages.
+    slots: [Slot<T>; BLOCK_CAP],
+}
+
+impl<T> Block<T> {
+    /// Creates an empty block.
+    fn new() -> Block<T> {
+        // SAFETY: This is safe because:
+        //  [1] `Block::next` (AtomicPtr) may be safely zero initialized.
+        //  [2] `Block::slots` (Array) may be safely zero initialized because of [3, 4].
+        //  [3] `Slot::msg` (UnsafeCell) may be safely zero initialized because it
+        //       holds a MaybeUninit.
+        //  [4] `Slot::state` (AtomicUsize) may be safely zero initialized.
+        unsafe { MaybeUninit::zeroed().assume_init() }
+    }
+
+    /// Waits until the next pointer is set.
+    fn wait_next(&self) -> *mut Block<T> {
+        let backoff = Backoff::new();
+        loop {
+            let next = self.next.load(Ordering::Acquire);
+            if !next.is_null() {
+                return next;
+            }
+            backoff.snooze();
+        }
+    }
+
+    /// Sets the `DESTROY` bit in slots starting from `start` and destroys the block.
+    unsafe fn destroy(this: *mut Block<T>, start: usize) {
+        // It is not necessary to set the `DESTROY` bit in the last slot because that slot has
+        // begun destruction of the block.
+        for i in start..BLOCK_CAP - 1 {
+            let slot = (*this).slots.get_unchecked(i);
+
+            // Mark the `DESTROY` bit if a thread is still using the slot.
+            if slot.state.load(Ordering::Acquire) & READ == 0
+                && slot.state.fetch_or(DESTROY, Ordering::AcqRel) & READ == 0
+            {
+                // If a thread is still using the slot, it will continue destruction of the block.
+                return;
+            }
+        }
+
+        // No thread is using the block, now it is safe to destroy it.
+        drop(Box::from_raw(this));
+    }
+}
+
+/// A position in a channel.
+#[derive(Debug)]
+struct Position<T> {
+    /// The index in the channel.
+    index: AtomicUsize,
+
+    /// The block in the linked list.
+    block: AtomicPtr<Block<T>>,
+}
+
+/// The token type for the list flavor.
+#[derive(Debug)]
+pub(crate) struct ListToken {
+    /// The block of slots.
+    block: *const u8,
+
+    /// The offset into the block.
+    offset: usize,
+}
+
+impl Default for ListToken {
+    #[inline]
+    fn default() -> Self {
+        ListToken { block: ptr::null(), offset: 0 }
+    }
+}
+
+/// Unbounded channel implemented as a linked list.
+///
+/// Each message sent into the channel is assigned a sequence number, i.e. an index. Indices are
+/// represented as numbers of type `usize` and wrap on overflow.
+///
+/// Consecutive messages are grouped into blocks in order to put less pressure on the allocator and
+/// improve cache efficiency.
+pub(crate) struct Channel<T> {
+    /// The head of the channel.
+    head: CachePadded<Position<T>>,
+
+    /// The tail of the channel.
+    tail: CachePadded<Position<T>>,
+
+    /// Receivers waiting while the channel is empty and not disconnected.
+    receivers: SyncWaker,
+
+    /// Indicates that dropping a `Channel<T>` may drop messages of type `T`.
+    _marker: PhantomData<T>,
+}
+
+impl<T> Channel<T> {
+    /// Creates a new unbounded channel.
+    pub(crate) fn new() -> Self {
+        Channel {
+            head: CachePadded::new(Position {
+                block: AtomicPtr::new(ptr::null_mut()),
+                index: AtomicUsize::new(0),
+            }),
+            tail: CachePadded::new(Position {
+                block: AtomicPtr::new(ptr::null_mut()),
+                index: AtomicUsize::new(0),
+            }),
+            receivers: SyncWaker::new(),
+            _marker: PhantomData,
+        }
+    }
+
+    /// Attempts to reserve a slot for sending a message.
+    fn start_send(&self, token: &mut Token) -> bool {
+        let backoff = Backoff::new();
+        let mut tail = self.tail.index.load(Ordering::Acquire);
+        let mut block = self.tail.block.load(Ordering::Acquire);
+        let mut next_block = None;
+
+        loop {
+            // Check if the channel is disconnected.
+            if tail & MARK_BIT != 0 {
+                token.list.block = ptr::null();
+                return true;
+            }
+
+            // Calculate the offset of the index into the block.
+            let offset = (tail >> SHIFT) % LAP;
+
+            // If we reached the end of the block, wait until the next one is installed.
+            if offset == BLOCK_CAP {
+                backoff.snooze();
+                tail = self.tail.index.load(Ordering::Acquire);
+                block = self.tail.block.load(Ordering::Acquire);
+                continue;
+            }
+
+            // If we're going to have to install the next block, allocate it in advance in order to
+            // make the wait for other threads as short as possible.
+            if offset + 1 == BLOCK_CAP && next_block.is_none() {
+                next_block = Some(Box::new(Block::<T>::new()));
+            }
+
+            // If this is the first message to be sent into the channel, we need to allocate the
+            // first block and install it.
+            if block.is_null() {
+                let new = Box::into_raw(Box::new(Block::<T>::new()));
+
+                if self
+                    .tail
+                    .block
+                    .compare_exchange(block, new, Ordering::Release, Ordering::Relaxed)
+                    .is_ok()
+                {
+                    self.head.block.store(new, Ordering::Release);
+                    block = new;
+                } else {
+                    next_block = unsafe { Some(Box::from_raw(new)) };
+                    tail = self.tail.index.load(Ordering::Acquire);
+                    block = self.tail.block.load(Ordering::Acquire);
+                    continue;
+                }
+            }
+
+            let new_tail = tail + (1 << SHIFT);
+
+            // Try advancing the tail forward.
+            match self.tail.index.compare_exchange_weak(
+                tail,
+                new_tail,
+                Ordering::SeqCst,
+                Ordering::Acquire,
+            ) {
+                Ok(_) => unsafe {
+                    // If we've reached the end of the block, install the next one.
+                    if offset + 1 == BLOCK_CAP {
+                        let next_block = Box::into_raw(next_block.unwrap());
+                        self.tail.block.store(next_block, Ordering::Release);
+                        self.tail.index.fetch_add(1 << SHIFT, Ordering::Release);
+                        (*block).next.store(next_block, Ordering::Release);
+                    }
+
+                    token.list.block = block as *const u8;
+                    token.list.offset = offset;
+                    return true;
+                },
+                Err(_) => {
+                    backoff.spin();
+                    tail = self.tail.index.load(Ordering::Acquire);
+                    block = self.tail.block.load(Ordering::Acquire);
+                }
+            }
+        }
+    }
+
+    /// Writes a message into the channel.
+    pub(crate) unsafe fn write(&self, token: &mut Token, msg: T) -> Result<(), T> {
+        // If there is no slot, the channel is disconnected.
+        if token.list.block.is_null() {
+            return Err(msg);
+        }
+
+        // Write the message into the slot.
+        let block = token.list.block as *mut Block<T>;
+        let offset = token.list.offset;
+        let slot = (*block).slots.get_unchecked(offset);
+        slot.msg.get().write(MaybeUninit::new(msg));
+        slot.state.fetch_or(WRITE, Ordering::Release);
+
+        // Wake a sleeping receiver.
+        self.receivers.notify();
+        Ok(())
+    }
+
+    /// Attempts to reserve a slot for receiving a message.
+    fn start_recv(&self, token: &mut Token) -> bool {
+        let backoff = Backoff::new();
+        let mut head = self.head.index.load(Ordering::Acquire);
+        let mut block = self.head.block.load(Ordering::Acquire);
+
+        loop {
+            // Calculate the offset of the index into the block.
+            let offset = (head >> SHIFT) % LAP;
+
+            // If we reached the end of the block, wait until the next one is installed.
+            if offset == BLOCK_CAP {
+                backoff.snooze();
+                head = self.head.index.load(Ordering::Acquire);
+                block = self.head.block.load(Ordering::Acquire);
+                continue;
+            }
+
+            let mut new_head = head + (1 << SHIFT);
+
+            if new_head & MARK_BIT == 0 {
+                atomic::fence(Ordering::SeqCst);
+                let tail = self.tail.index.load(Ordering::Relaxed);
+
+                // If the tail equals the head, that means the channel is empty.
+                if head >> SHIFT == tail >> SHIFT {
+                    // If the channel is disconnected...
+                    if tail & MARK_BIT != 0 {
+                        // ...then receive an error.
+                        token.list.block = ptr::null();
+                        return true;
+                    } else {
+                        // Otherwise, the receive operation is not ready.
+                        return false;
+                    }
+                }
+
+                // If head and tail are not in the same block, set `MARK_BIT` in head.
+                if (head >> SHIFT) / LAP != (tail >> SHIFT) / LAP {
+                    new_head |= MARK_BIT;
+                }
+            }
+
+            // The block can be null here only if the first message is being sent into the channel.
+            // In that case, just wait until it gets initialized.
+            if block.is_null() {
+                backoff.snooze();
+                head = self.head.index.load(Ordering::Acquire);
+                block = self.head.block.load(Ordering::Acquire);
+                continue;
+            }
+
+            // Try moving the head index forward.
+            match self.head.index.compare_exchange_weak(
+                head,
+                new_head,
+                Ordering::SeqCst,
+                Ordering::Acquire,
+            ) {
+                Ok(_) => unsafe {
+                    // If we've reached the end of the block, move to the next one.
+                    if offset + 1 == BLOCK_CAP {
+                        let next = (*block).wait_next();
+                        let mut next_index = (new_head & !MARK_BIT).wrapping_add(1 << SHIFT);
+                        if !(*next).next.load(Ordering::Relaxed).is_null() {
+                            next_index |= MARK_BIT;
+                        }
+
+                        self.head.block.store(next, Ordering::Release);
+                        self.head.index.store(next_index, Ordering::Release);
+                    }
+
+                    token.list.block = block as *const u8;
+                    token.list.offset = offset;
+                    return true;
+                },
+                Err(_) => {
+                    backoff.spin();
+                    head = self.head.index.load(Ordering::Acquire);
+                    block = self.head.block.load(Ordering::Acquire);
+                }
+            }
+        }
+    }
+
+    /// Reads a message from the channel.
+    pub(crate) unsafe fn read(&self, token: &mut Token) -> Result<T, ()> {
+        if token.list.block.is_null() {
+            // The channel is disconnected.
+            return Err(());
+        }
+
+        // Read the message.
+        let block = token.list.block as *mut Block<T>;
+        let offset = token.list.offset;
+        let slot = (*block).slots.get_unchecked(offset);
+        slot.wait_write();
+        let msg = slot.msg.get().read().assume_init();
+
+        // Destroy the block if we've reached the end, or if another thread wanted to destroy but
+        // couldn't because we were busy reading from the slot.
+        if offset + 1 == BLOCK_CAP {
+            Block::destroy(block, 0);
+        } else if slot.state.fetch_or(READ, Ordering::AcqRel) & DESTROY != 0 {
+            Block::destroy(block, offset + 1);
+        }
+
+        Ok(msg)
+    }
+
+    /// Attempts to send a message into the channel.
+    pub(crate) fn try_send(&self, msg: T) -> Result<(), TrySendError<T>> {
+        self.send(msg, None).map_err(|err| match err {
+            SendTimeoutError::Disconnected(msg) => TrySendError::Disconnected(msg),
+            SendTimeoutError::Timeout(_) => unreachable!(),
+        })
+    }
+
+    /// Sends a message into the channel.
+    pub(crate) fn send(
+        &self,
+        msg: T,
+        _deadline: Option<Instant>,
+    ) -> Result<(), SendTimeoutError<T>> {
+        let token = &mut Token::default();
+        assert!(self.start_send(token));
+        unsafe { self.write(token, msg).map_err(SendTimeoutError::Disconnected) }
+    }
+
+    /// Attempts to receive a message without blocking.
+    pub(crate) fn try_recv(&self) -> Result<T, TryRecvError> {
+        let token = &mut Token::default();
+
+        if self.start_recv(token) {
+            unsafe { self.read(token).map_err(|_| TryRecvError::Disconnected) }
+        } else {
+            Err(TryRecvError::Empty)
+        }
+    }
+
+    /// Receives a message from the channel.
+    pub(crate) fn recv(&self, deadline: Option<Instant>) -> Result<T, RecvTimeoutError> {
+        let token = &mut Token::default();
+        loop {
+            if self.start_recv(token) {
+                unsafe {
+                    return self.read(token).map_err(|_| RecvTimeoutError::Disconnected);
+                }
+            }
+
+            if let Some(d) = deadline {
+                if Instant::now() >= d {
+                    return Err(RecvTimeoutError::Timeout);
+                }
+            }
+
+            // Prepare for blocking until a sender wakes us up.
+            Context::with(|cx| {
+                let oper = Operation::hook(token);
+                self.receivers.register(oper, cx);
+
+                // Has the channel become ready just now?
+                if !self.is_empty() || self.is_disconnected() {
+                    let _ = cx.try_select(Selected::Aborted);
+                }
+
+                // Block the current thread.
+                let sel = cx.wait_until(deadline);
+
+                match sel {
+                    Selected::Waiting => unreachable!(),
+                    Selected::Aborted | Selected::Disconnected => {
+                        self.receivers.unregister(oper).unwrap();
+                        // If the channel was disconnected, we still have to check for remaining
+                        // messages.
+                    }
+                    Selected::Operation(_) => {}
+                }
+            });
+        }
+    }
+
+    /// Returns the current number of messages inside the channel.
+    pub(crate) fn len(&self) -> usize {
+        loop {
+            // Load the tail index, then load the head index.
+            let mut tail = self.tail.index.load(Ordering::SeqCst);
+            let mut head = self.head.index.load(Ordering::SeqCst);
+
+            // If the tail index didn't change, we've got consistent indices to work with.
+            if self.tail.index.load(Ordering::SeqCst) == tail {
+                // Erase the lower bits.
+                tail &= !((1 << SHIFT) - 1);
+                head &= !((1 << SHIFT) - 1);
+
+                // Fix up indices if they fall onto block ends.
+                if (tail >> SHIFT) & (LAP - 1) == LAP - 1 {
+                    tail = tail.wrapping_add(1 << SHIFT);
+                }
+                if (head >> SHIFT) & (LAP - 1) == LAP - 1 {
+                    head = head.wrapping_add(1 << SHIFT);
+                }
+
+                // Rotate indices so that head falls into the first block.
+                let lap = (head >> SHIFT) / LAP;
+                tail = tail.wrapping_sub((lap * LAP) << SHIFT);
+                head = head.wrapping_sub((lap * LAP) << SHIFT);
+
+                // Remove the lower bits.
+                tail >>= SHIFT;
+                head >>= SHIFT;
+
+                // Return the difference minus the number of blocks between tail and head.
+                return tail - head - tail / LAP;
+            }
+        }
+    }
+
+    /// Returns the capacity of the channel.
+    pub(crate) fn capacity(&self) -> Option<usize> {
+        None
+    }
+
+    /// Disconnects senders and wakes up all blocked receivers.
+    ///
+    /// Returns `true` if this call disconnected the channel.
+    pub(crate) fn disconnect_senders(&self) -> bool {
+        let tail = self.tail.index.fetch_or(MARK_BIT, Ordering::SeqCst);
+
+        if tail & MARK_BIT == 0 {
+            self.receivers.disconnect();
+            true
+        } else {
+            false
+        }
+    }
+
+    /// Disconnects receivers.
+    ///
+    /// Returns `true` if this call disconnected the channel.
+    pub(crate) fn disconnect_receivers(&self) -> bool {
+        let tail = self.tail.index.fetch_or(MARK_BIT, Ordering::SeqCst);
+
+        if tail & MARK_BIT == 0 {
+            // If receivers are dropped first, discard all messages to free
+            // memory eagerly.
+            self.discard_all_messages();
+            true
+        } else {
+            false
+        }
+    }
+
+    /// Discards all messages.
+    ///
+    /// This method should only be called when all receivers are dropped.
+    fn discard_all_messages(&self) {
+        let backoff = Backoff::new();
+        let mut tail = self.tail.index.load(Ordering::Acquire);
+        loop {
+            let offset = (tail >> SHIFT) % LAP;
+            if offset != BLOCK_CAP {
+                break;
+            }
+
+            // New updates to tail will be rejected by MARK_BIT and aborted unless it's
+            // at boundary. We need to wait for the updates take affect otherwise there
+            // can be memory leaks.
+            backoff.snooze();
+            tail = self.tail.index.load(Ordering::Acquire);
+        }
+
+        let mut head = self.head.index.load(Ordering::Acquire);
+        let mut block = self.head.block.load(Ordering::Acquire);
+
+        unsafe {
+            // Drop all messages between head and tail and deallocate the heap-allocated blocks.
+            while head >> SHIFT != tail >> SHIFT {
+                let offset = (head >> SHIFT) % LAP;
+
+                if offset < BLOCK_CAP {
+                    // Drop the message in the slot.
+                    let slot = (*block).slots.get_unchecked(offset);
+                    slot.wait_write();
+                    let p = &mut *slot.msg.get();
+                    p.as_mut_ptr().drop_in_place();
+                } else {
+                    (*block).wait_next();
+                    // Deallocate the block and move to the next one.
+                    let next = (*block).next.load(Ordering::Acquire);
+                    drop(Box::from_raw(block));
+                    block = next;
+                }
+
+                head = head.wrapping_add(1 << SHIFT);
+            }
+
+            // Deallocate the last remaining block.
+            if !block.is_null() {
+                drop(Box::from_raw(block));
+            }
+        }
+        head &= !MARK_BIT;
+        self.head.block.store(ptr::null_mut(), Ordering::Release);
+        self.head.index.store(head, Ordering::Release);
+    }
+
+    /// Returns `true` if the channel is disconnected.
+    pub(crate) fn is_disconnected(&self) -> bool {
+        self.tail.index.load(Ordering::SeqCst) & MARK_BIT != 0
+    }
+
+    /// Returns `true` if the channel is empty.
+    pub(crate) fn is_empty(&self) -> bool {
+        let head = self.head.index.load(Ordering::SeqCst);
+        let tail = self.tail.index.load(Ordering::SeqCst);
+        head >> SHIFT == tail >> SHIFT
+    }
+
+    /// Returns `true` if the channel is full.
+    pub(crate) fn is_full(&self) -> bool {
+        false
+    }
+}
+
+impl<T> Drop for Channel<T> {
+    fn drop(&mut self) {
+        let mut head = self.head.index.load(Ordering::Relaxed);
+        let mut tail = self.tail.index.load(Ordering::Relaxed);
+        let mut block = self.head.block.load(Ordering::Relaxed);
+
+        // Erase the lower bits.
+        head &= !((1 << SHIFT) - 1);
+        tail &= !((1 << SHIFT) - 1);
+
+        unsafe {
+            // Drop all messages between head and tail and deallocate the heap-allocated blocks.
+            while head != tail {
+                let offset = (head >> SHIFT) % LAP;
+
+                if offset < BLOCK_CAP {
+                    // Drop the message in the slot.
+                    let slot = (*block).slots.get_unchecked(offset);
+                    let p = &mut *slot.msg.get();
+                    p.as_mut_ptr().drop_in_place();
+                } else {
+                    // Deallocate the block and move to the next one.
+                    let next = (*block).next.load(Ordering::Relaxed);
+                    drop(Box::from_raw(block));
+                    block = next;
+                }
+
+                head = head.wrapping_add(1 << SHIFT);
+            }
+
+            // Deallocate the last remaining block.
+            if !block.is_null() {
+                drop(Box::from_raw(block));
+            }
+        }
+    }
+}
diff --git a/library/std/src/sync/mpmc/mod.rs b/library/std/src/sync/mpmc/mod.rs
new file mode 100644
index 000000000000..cef99c588430
--- /dev/null
+++ b/library/std/src/sync/mpmc/mod.rs
@@ -0,0 +1,430 @@
+//! Multi-producer multi-consumer channels.
+
+// This module is not currently exposed publicly, but is used
+// as the implementation for the channels in `sync::mpsc`. The
+// implementation comes from the crossbeam-channel crate:
+//
+// Copyright (c) 2019 The Crossbeam Project Developers
+//
+// Permission is hereby granted, free of charge, to any
+// person obtaining a copy of this software and associated
+// documentation files (the "Software"), to deal in the
+// Software without restriction, including without
+// limitation the rights to use, copy, modify, merge,
+// publish, distribute, sublicense, and/or sell copies of
+// the Software, and to permit persons to whom the Software
+// is furnished to do so, subject to the following
+// conditions:
+//
+// The above copyright notice and this permission notice
+// shall be included in all copies or substantial portions
+// of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+// ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+// TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+// PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
+// SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+// CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+// IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+// DEALINGS IN THE SOFTWARE.
+
+mod array;
+mod context;
+mod counter;
+mod error;
+mod list;
+mod select;
+mod utils;
+mod waker;
+mod zero;
+
+use crate::fmt;
+use crate::panic::{RefUnwindSafe, UnwindSafe};
+use crate::time::{Duration, Instant};
+use error::*;
+
+/// Creates a channel of unbounded capacity.
+///
+/// This channel has a growable buffer that can hold any number of messages at a time.
+pub fn channel<T>() -> (Sender<T>, Receiver<T>) {
+    let (s, r) = counter::new(list::Channel::new());
+    let s = Sender { flavor: SenderFlavor::List(s) };
+    let r = Receiver { flavor: ReceiverFlavor::List(r) };
+    (s, r)
+}
+
+/// Creates a channel of bounded capacity.
+///
+/// This channel has a buffer that can hold at most `cap` messages at a time.
+///
+/// A special case is zero-capacity channel, which cannot hold any messages. Instead, send and
+/// receive operations must appear at the same time in order to pair up and pass the message over.
+pub fn sync_channel<T>(cap: usize) -> (Sender<T>, Receiver<T>) {
+    if cap == 0 {
+        let (s, r) = counter::new(zero::Channel::new());
+        let s = Sender { flavor: SenderFlavor::Zero(s) };
+        let r = Receiver { flavor: ReceiverFlavor::Zero(r) };
+        (s, r)
+    } else {
+        let (s, r) = counter::new(array::Channel::with_capacity(cap));
+        let s = Sender { flavor: SenderFlavor::Array(s) };
+        let r = Receiver { flavor: ReceiverFlavor::Array(r) };
+        (s, r)
+    }
+}
+
+/// The sending side of a channel.
+pub struct Sender<T> {
+    flavor: SenderFlavor<T>,
+}
+
+/// Sender flavors.
+enum SenderFlavor<T> {
+    /// Bounded channel based on a preallocated array.
+    Array(counter::Sender<array::Channel<T>>),
+
+    /// Unbounded channel implemented as a linked list.
+    List(counter::Sender<list::Channel<T>>),
+
+    /// Zero-capacity channel.
+    Zero(counter::Sender<zero::Channel<T>>),
+}
+
+unsafe impl<T: Send> Send for Sender<T> {}
+unsafe impl<T: Send> Sync for Sender<T> {}
+
+impl<T> UnwindSafe for Sender<T> {}
+impl<T> RefUnwindSafe for Sender<T> {}
+
+impl<T> Sender<T> {
+    /// Attempts to send a message into the channel without blocking.
+    ///
+    /// This method will either send a message into the channel immediately or return an error if
+    /// the channel is full or disconnected. The returned error contains the original message.
+    ///
+    /// If called on a zero-capacity channel, this method will send the message only if there
+    /// happens to be a receive operation on the other side of the channel at the same time.
+    pub fn try_send(&self, msg: T) -> Result<(), TrySendError<T>> {
+        match &self.flavor {
+            SenderFlavor::Array(chan) => chan.try_send(msg),
+            SenderFlavor::List(chan) => chan.try_send(msg),
+            SenderFlavor::Zero(chan) => chan.try_send(msg),
+        }
+    }
+
+    /// Blocks the current thread until a message is sent or the channel is disconnected.
+    ///
+    /// If the channel is full and not disconnected, this call will block until the send operation
+    /// can proceed. If the channel becomes disconnected, this call will wake up and return an
+    /// error. The returned error contains the original message.
+    ///
+    /// If called on a zero-capacity channel, this method will wait for a receive operation to
+    /// appear on the other side of the channel.
+    pub fn send(&self, msg: T) -> Result<(), SendError<T>> {
+        match &self.flavor {
+            SenderFlavor::Array(chan) => chan.send(msg, None),
+            SenderFlavor::List(chan) => chan.send(msg, None),
+            SenderFlavor::Zero(chan) => chan.send(msg, None),
+        }
+        .map_err(|err| match err {
+            SendTimeoutError::Disconnected(msg) => SendError(msg),
+            SendTimeoutError::Timeout(_) => unreachable!(),
+        })
+    }
+}
+
+// The methods below are not used by `sync::mpsc`, but
+// are useful and we'll likely want to expose them
+// eventually
+#[allow(unused)]
+impl<T> Sender<T> {
+    /// Waits for a message to be sent into the channel, but only for a limited time.
+    ///
+    /// If the channel is full and not disconnected, this call will block until the send operation
+    /// can proceed or the operation times out. If the channel becomes disconnected, this call will
+    /// wake up and return an error. The returned error contains the original message.
+    ///
+    /// If called on a zero-capacity channel, this method will wait for a receive operation to
+    /// appear on the other side of the channel.
+    pub fn send_timeout(&self, msg: T, timeout: Duration) -> Result<(), SendTimeoutError<T>> {
+        match Instant::now().checked_add(timeout) {
+            Some(deadline) => self.send_deadline(msg, deadline),
+            // So far in the future that it's practically the same as waiting indefinitely.
+            None => self.send(msg).map_err(SendTimeoutError::from),
+        }
+    }
+
+    /// Waits for a message to be sent into the channel, but only until a given deadline.
+    ///
+    /// If the channel is full and not disconnected, this call will block until the send operation
+    /// can proceed or the operation times out. If the channel becomes disconnected, this call will
+    /// wake up and return an error. The returned error contains the original message.
+    ///
+    /// If called on a zero-capacity channel, this method will wait for a receive operation to
+    /// appear on the other side of the channel.
+    pub fn send_deadline(&self, msg: T, deadline: Instant) -> Result<(), SendTimeoutError<T>> {
+        match &self.flavor {
+            SenderFlavor::Array(chan) => chan.send(msg, Some(deadline)),
+            SenderFlavor::List(chan) => chan.send(msg, Some(deadline)),
+            SenderFlavor::Zero(chan) => chan.send(msg, Some(deadline)),
+        }
+    }
+
+    /// Returns `true` if the channel is empty.
+    ///
+    /// Note: Zero-capacity channels are always empty.
+    pub fn is_empty(&self) -> bool {
+        match &self.flavor {
+            SenderFlavor::Array(chan) => chan.is_empty(),
+            SenderFlavor::List(chan) => chan.is_empty(),
+            SenderFlavor::Zero(chan) => chan.is_empty(),
+        }
+    }
+
+    /// Returns `true` if the channel is full.
+    ///
+    /// Note: Zero-capacity channels are always full.
+    pub fn is_full(&self) -> bool {
+        match &self.flavor {
+            SenderFlavor::Array(chan) => chan.is_full(),
+            SenderFlavor::List(chan) => chan.is_full(),
+            SenderFlavor::Zero(chan) => chan.is_full(),
+        }
+    }
+
+    /// Returns the number of messages in the channel.
+    pub fn len(&self) -> usize {
+        match &self.flavor {
+            SenderFlavor::Array(chan) => chan.len(),
+            SenderFlavor::List(chan) => chan.len(),
+            SenderFlavor::Zero(chan) => chan.len(),
+        }
+    }
+
+    /// If the channel is bounded, returns its capacity.
+    pub fn capacity(&self) -> Option<usize> {
+        match &self.flavor {
+            SenderFlavor::Array(chan) => chan.capacity(),
+            SenderFlavor::List(chan) => chan.capacity(),
+            SenderFlavor::Zero(chan) => chan.capacity(),
+        }
+    }
+
+    /// Returns `true` if senders belong to the same channel.
+    pub fn same_channel(&self, other: &Sender<T>) -> bool {
+        match (&self.flavor, &other.flavor) {
+            (SenderFlavor::Array(ref a), SenderFlavor::Array(ref b)) => a == b,
+            (SenderFlavor::List(ref a), SenderFlavor::List(ref b)) => a == b,
+            (SenderFlavor::Zero(ref a), SenderFlavor::Zero(ref b)) => a == b,
+            _ => false,
+        }
+    }
+}
+
+impl<T> Drop for Sender<T> {
+    fn drop(&mut self) {
+        unsafe {
+            match &self.flavor {
+                SenderFlavor::Array(chan) => chan.release(|c| c.disconnect()),
+                SenderFlavor::List(chan) => chan.release(|c| c.disconnect_senders()),
+                SenderFlavor::Zero(chan) => chan.release(|c| c.disconnect()),
+            }
+        }
+    }
+}
+
+impl<T> Clone for Sender<T> {
+    fn clone(&self) -> Self {
+        let flavor = match &self.flavor {
+            SenderFlavor::Array(chan) => SenderFlavor::Array(chan.acquire()),
+            SenderFlavor::List(chan) => SenderFlavor::List(chan.acquire()),
+            SenderFlavor::Zero(chan) => SenderFlavor::Zero(chan.acquire()),
+        };
+
+        Sender { flavor }
+    }
+}
+
+impl<T> fmt::Debug for Sender<T> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.pad("Sender { .. }")
+    }
+}
+
+/// The receiving side of a channel.
+pub struct Receiver<T> {
+    flavor: ReceiverFlavor<T>,
+}
+
+/// Receiver flavors.
+enum ReceiverFlavor<T> {
+    /// Bounded channel based on a preallocated array.
+    Array(counter::Receiver<array::Channel<T>>),
+
+    /// Unbounded channel implemented as a linked list.
+    List(counter::Receiver<list::Channel<T>>),
+
+    /// Zero-capacity channel.
+    Zero(counter::Receiver<zero::Channel<T>>),
+}
+
+unsafe impl<T: Send> Send for Receiver<T> {}
+unsafe impl<T: Send> Sync for Receiver<T> {}
+
+impl<T> UnwindSafe for Receiver<T> {}
+impl<T> RefUnwindSafe for Receiver<T> {}
+
+impl<T> Receiver<T> {
+    /// Attempts to receive a message from the channel without blocking.
+    ///
+    /// This method will either receive a message from the channel immediately or return an error
+    /// if the channel is empty.
+    ///
+    /// If called on a zero-capacity channel, this method will receive a message only if there
+    /// happens to be a send operation on the other side of the channel at the same time.
+    pub fn try_recv(&self) -> Result<T, TryRecvError> {
+        match &self.flavor {
+            ReceiverFlavor::Array(chan) => chan.try_recv(),
+            ReceiverFlavor::List(chan) => chan.try_recv(),
+            ReceiverFlavor::Zero(chan) => chan.try_recv(),
+        }
+    }
+
+    /// Blocks the current thread until a message is received or the channel is empty and
+    /// disconnected.
+    ///
+    /// If the channel is empty and not disconnected, this call will block until the receive
+    /// operation can proceed. If the channel is empty and becomes disconnected, this call will
+    /// wake up and return an error.
+    ///
+    /// If called on a zero-capacity channel, this method will wait for a send operation to appear
+    /// on the other side of the channel.
+    pub fn recv(&self) -> Result<T, RecvError> {
+        match &self.flavor {
+            ReceiverFlavor::Array(chan) => chan.recv(None),
+            ReceiverFlavor::List(chan) => chan.recv(None),
+            ReceiverFlavor::Zero(chan) => chan.recv(None),
+        }
+        .map_err(|_| RecvError)
+    }
+
+    /// Waits for a message to be received from the channel, but only for a limited time.
+    ///
+    /// If the channel is empty and not disconnected, this call will block until the receive
+    /// operation can proceed or the operation times out. If the channel is empty and becomes
+    /// disconnected, this call will wake up and return an error.
+    ///
+    /// If called on a zero-capacity channel, this method will wait for a send operation to appear
+    /// on the other side of the channel.
+    pub fn recv_timeout(&self, timeout: Duration) -> Result<T, RecvTimeoutError> {
+        match Instant::now().checked_add(timeout) {
+            Some(deadline) => self.recv_deadline(deadline),
+            // So far in the future that it's practically the same as waiting indefinitely.
+            None => self.recv().map_err(RecvTimeoutError::from),
+        }
+    }
+
+    /// Waits for a message to be received from the channel, but only for a limited time.
+    ///
+    /// If the channel is empty and not disconnected, this call will block until the receive
+    /// operation can proceed or the operation times out. If the channel is empty and becomes
+    /// disconnected, this call will wake up and return an error.
+    ///
+    /// If called on a zero-capacity channel, this method will wait for a send operation to appear
+    /// on the other side of the channel.
+    pub fn recv_deadline(&self, deadline: Instant) -> Result<T, RecvTimeoutError> {
+        match &self.flavor {
+            ReceiverFlavor::Array(chan) => chan.recv(Some(deadline)),
+            ReceiverFlavor::List(chan) => chan.recv(Some(deadline)),
+            ReceiverFlavor::Zero(chan) => chan.recv(Some(deadline)),
+        }
+    }
+}
+
+// The methods below are not used by `sync::mpsc`, but
+// are useful and we'll likely want to expose them
+// eventually
+#[allow(unused)]
+impl<T> Receiver<T> {
+    /// Returns `true` if the channel is empty.
+    ///
+    /// Note: Zero-capacity channels are always empty.
+    pub fn is_empty(&self) -> bool {
+        match &self.flavor {
+            ReceiverFlavor::Array(chan) => chan.is_empty(),
+            ReceiverFlavor::List(chan) => chan.is_empty(),
+            ReceiverFlavor::Zero(chan) => chan.is_empty(),
+        }
+    }
+
+    /// Returns `true` if the channel is full.
+    ///
+    /// Note: Zero-capacity channels are always full.
+    pub fn is_full(&self) -> bool {
+        match &self.flavor {
+            ReceiverFlavor::Array(chan) => chan.is_full(),
+            ReceiverFlavor::List(chan) => chan.is_full(),
+            ReceiverFlavor::Zero(chan) => chan.is_full(),
+        }
+    }
+
+    /// Returns the number of messages in the channel.
+    pub fn len(&self) -> usize {
+        match &self.flavor {
+            ReceiverFlavor::Array(chan) => chan.len(),
+            ReceiverFlavor::List(chan) => chan.len(),
+            ReceiverFlavor::Zero(chan) => chan.len(),
+        }
+    }
+
+    /// If the channel is bounded, returns its capacity.
+    pub fn capacity(&self) -> Option<usize> {
+        match &self.flavor {
+            ReceiverFlavor::Array(chan) => chan.capacity(),
+            ReceiverFlavor::List(chan) => chan.capacity(),
+            ReceiverFlavor::Zero(chan) => chan.capacity(),
+        }
+    }
+
+    /// Returns `true` if receivers belong to the same channel.
+    pub fn same_channel(&self, other: &Receiver<T>) -> bool {
+        match (&self.flavor, &other.flavor) {
+            (ReceiverFlavor::Array(a), ReceiverFlavor::Array(b)) => a == b,
+            (ReceiverFlavor::List(a), ReceiverFlavor::List(b)) => a == b,
+            (ReceiverFlavor::Zero(a), ReceiverFlavor::Zero(b)) => a == b,
+            _ => false,
+        }
+    }
+}
+
+impl<T> Drop for Receiver<T> {
+    fn drop(&mut self) {
+        unsafe {
+            match &self.flavor {
+                ReceiverFlavor::Array(chan) => chan.release(|c| c.disconnect()),
+                ReceiverFlavor::List(chan) => chan.release(|c| c.disconnect_receivers()),
+                ReceiverFlavor::Zero(chan) => chan.release(|c| c.disconnect()),
+            }
+        }
+    }
+}
+
+impl<T> Clone for Receiver<T> {
+    fn clone(&self) -> Self {
+        let flavor = match &self.flavor {
+            ReceiverFlavor::Array(chan) => ReceiverFlavor::Array(chan.acquire()),
+            ReceiverFlavor::List(chan) => ReceiverFlavor::List(chan.acquire()),
+            ReceiverFlavor::Zero(chan) => ReceiverFlavor::Zero(chan.acquire()),
+        };
+
+        Receiver { flavor }
+    }
+}
+
+impl<T> fmt::Debug for Receiver<T> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.pad("Receiver { .. }")
+    }
+}
diff --git a/library/std/src/sync/mpmc/select.rs b/library/std/src/sync/mpmc/select.rs
new file mode 100644
index 000000000000..56a83fee2e11
--- /dev/null
+++ b/library/std/src/sync/mpmc/select.rs
@@ -0,0 +1,71 @@
+/// Temporary data that gets initialized during a blocking operation, and is consumed by
+/// `read` or `write`.
+///
+/// Each field contains data associated with a specific channel flavor.
+#[derive(Debug, Default)]
+pub struct Token {
+    pub(crate) array: super::array::ArrayToken,
+    pub(crate) list: super::list::ListToken,
+    #[allow(dead_code)]
+    pub(crate) zero: super::zero::ZeroToken,
+}
+
+/// Identifier associated with an operation by a specific thread on a specific channel.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub struct Operation(usize);
+
+impl Operation {
+    /// Creates an operation identifier from a mutable reference.
+    ///
+    /// This function essentially just turns the address of the reference into a number. The
+    /// reference should point to a variable that is specific to the thread and the operation,
+    /// and is alive for the entire duration of a blocking operation.
+    #[inline]
+    pub fn hook<T>(r: &mut T) -> Operation {
+        let val = r as *mut T as usize;
+        // Make sure that the pointer address doesn't equal the numerical representation of
+        // `Selected::{Waiting, Aborted, Disconnected}`.
+        assert!(val > 2);
+        Operation(val)
+    }
+}
+
+/// Current state of a blocking operation.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum Selected {
+    /// Still waiting for an operation.
+    Waiting,
+
+    /// The attempt to block the current thread has been aborted.
+    Aborted,
+
+    /// An operation became ready because a channel is disconnected.
+    Disconnected,
+
+    /// An operation became ready because a message can be sent or received.
+    Operation(Operation),
+}
+
+impl From<usize> for Selected {
+    #[inline]
+    fn from(val: usize) -> Selected {
+        match val {
+            0 => Selected::Waiting,
+            1 => Selected::Aborted,
+            2 => Selected::Disconnected,
+            oper => Selected::Operation(Operation(oper)),
+        }
+    }
+}
+
+impl Into<usize> for Selected {
+    #[inline]
+    fn into(self) -> usize {
+        match self {
+            Selected::Waiting => 0,
+            Selected::Aborted => 1,
+            Selected::Disconnected => 2,
+            Selected::Operation(Operation(val)) => val,
+        }
+    }
+}
diff --git a/library/std/src/sync/mpmc/utils.rs b/library/std/src/sync/mpmc/utils.rs
new file mode 100644
index 000000000000..d0904b4b94cb
--- /dev/null
+++ b/library/std/src/sync/mpmc/utils.rs
@@ -0,0 +1,144 @@
+use crate::cell::Cell;
+use crate::ops::{Deref, DerefMut};
+
+/// Pads and aligns a value to the length of a cache line.
+#[derive(Clone, Copy, Default, Hash, PartialEq, Eq)]
+// Starting from Intel's Sandy Bridge, spatial prefetcher is now pulling pairs of 64-byte cache
+// lines at a time, so we have to align to 128 bytes rather than 64.
+//
+// Sources:
+// - https://www.intel.com/content/dam/www/public/us/en/documents/manuals/64-ia-32-architectures-optimization-manual.pdf
+// - https://github.com/facebook/folly/blob/1b5288e6eea6df074758f877c849b6e73bbb9fbb/folly/lang/Align.h#L107
+//
+// ARM's big.LITTLE architecture has asymmetric cores and "big" cores have 128-byte cache line size.
+//
+// Sources:
+// - https://www.mono-project.com/news/2016/09/12/arm64-icache/
+//
+// powerpc64 has 128-byte cache line size.
+//
+// Sources:
+// - https://github.com/golang/go/blob/3dd58676054223962cd915bb0934d1f9f489d4d2/src/internal/cpu/cpu_ppc64x.go#L9
+#[cfg_attr(
+    any(target_arch = "x86_64", target_arch = "aarch64", target_arch = "powerpc64",),
+    repr(align(128))
+)]
+// arm, mips, mips64, and riscv64 have 32-byte cache line size.
+//
+// Sources:
+// - https://github.com/golang/go/blob/3dd58676054223962cd915bb0934d1f9f489d4d2/src/internal/cpu/cpu_arm.go#L7
+// - https://github.com/golang/go/blob/3dd58676054223962cd915bb0934d1f9f489d4d2/src/internal/cpu/cpu_mips.go#L7
+// - https://github.com/golang/go/blob/3dd58676054223962cd915bb0934d1f9f489d4d2/src/internal/cpu/cpu_mipsle.go#L7
+// - https://github.com/golang/go/blob/3dd58676054223962cd915bb0934d1f9f489d4d2/src/internal/cpu/cpu_mips64x.go#L9
+// - https://github.com/golang/go/blob/3dd58676054223962cd915bb0934d1f9f489d4d2/src/internal/cpu/cpu_riscv64.go#L7
+#[cfg_attr(
+    any(
+        target_arch = "arm",
+        target_arch = "mips",
+        target_arch = "mips64",
+        target_arch = "riscv64",
+    ),
+    repr(align(32))
+)]
+// s390x has 256-byte cache line size.
+//
+// Sources:
+// - https://github.com/golang/go/blob/3dd58676054223962cd915bb0934d1f9f489d4d2/src/internal/cpu/cpu_s390x.go#L7
+#[cfg_attr(target_arch = "s390x", repr(align(256)))]
+// x86 and wasm have 64-byte cache line size.
+//
+// Sources:
+// - https://github.com/golang/go/blob/dda2991c2ea0c5914714469c4defc2562a907230/src/internal/cpu/cpu_x86.go#L9
+// - https://github.com/golang/go/blob/3dd58676054223962cd915bb0934d1f9f489d4d2/src/internal/cpu/cpu_wasm.go#L7
+//
+// All others are assumed to have 64-byte cache line size.
+#[cfg_attr(
+    not(any(
+        target_arch = "x86_64",
+        target_arch = "aarch64",
+        target_arch = "powerpc64",
+        target_arch = "arm",
+        target_arch = "mips",
+        target_arch = "mips64",
+        target_arch = "riscv64",
+        target_arch = "s390x",
+    )),
+    repr(align(64))
+)]
+pub struct CachePadded<T> {
+    value: T,
+}
+
+impl<T> CachePadded<T> {
+    /// Pads and aligns a value to the length of a cache line.
+    pub fn new(value: T) -> CachePadded<T> {
+        CachePadded::<T> { value }
+    }
+}
+
+impl<T> Deref for CachePadded<T> {
+    type Target = T;
+
+    fn deref(&self) -> &T {
+        &self.value
+    }
+}
+
+impl<T> DerefMut for CachePadded<T> {
+    fn deref_mut(&mut self) -> &mut T {
+        &mut self.value
+    }
+}
+
+const SPIN_LIMIT: u32 = 6;
+const YIELD_LIMIT: u32 = 10;
+
+/// Performs exponential backoff in spin loops.
+pub struct Backoff {
+    step: Cell<u32>,
+}
+
+impl Backoff {
+    /// Creates a new `Backoff`.
+    pub fn new() -> Self {
+        Backoff { step: Cell::new(0) }
+    }
+
+    /// Backs off in a lock-free loop.
+    ///
+    /// This method should be used when we need to retry an operation because another thread made
+    /// progress.
+    #[inline]
+    pub fn spin(&self) {
+        let step = self.step.get().min(SPIN_LIMIT);
+        for _ in 0..step.pow(2) {
+            crate::hint::spin_loop();
+        }
+
+        if self.step.get() <= SPIN_LIMIT {
+            self.step.set(self.step.get() + 1);
+        }
+    }
+
+    /// Backs off in a blocking loop.
+    #[inline]
+    pub fn snooze(&self) {
+        if self.step.get() <= SPIN_LIMIT {
+            for _ in 0..self.step.get().pow(2) {
+                crate::hint::spin_loop()
+            }
+        } else {
+            crate::thread::yield_now();
+        }
+
+        if self.step.get() <= YIELD_LIMIT {
+            self.step.set(self.step.get() + 1);
+        }
+    }
+
+    /// Returns `true` if exponential backoff has completed and blocking the thread is advised.
+    #[inline]
+    pub fn is_completed(&self) -> bool {
+        self.step.get() > YIELD_LIMIT
+    }
+}
diff --git a/library/std/src/sync/mpmc/waker.rs b/library/std/src/sync/mpmc/waker.rs
new file mode 100644
index 000000000000..4912ca4f8150
--- /dev/null
+++ b/library/std/src/sync/mpmc/waker.rs
@@ -0,0 +1,204 @@
+//! Waking mechanism for threads blocked on channel operations.
+
+use super::context::Context;
+use super::select::{Operation, Selected};
+
+use crate::ptr;
+use crate::sync::atomic::{AtomicBool, Ordering};
+use crate::sync::Mutex;
+
+/// Represents a thread blocked on a specific channel operation.
+pub(crate) struct Entry {
+    /// The operation.
+    pub(crate) oper: Operation,
+
+    /// Optional packet.
+    pub(crate) packet: *mut (),
+
+    /// Context associated with the thread owning this operation.
+    pub(crate) cx: Context,
+}
+
+/// A queue of threads blocked on channel operations.
+///
+/// This data structure is used by threads to register blocking operations and get woken up once
+/// an operation becomes ready.
+pub(crate) struct Waker {
+    /// A list of select operations.
+    selectors: Vec<Entry>,
+
+    /// A list of operations waiting to be ready.
+    observers: Vec<Entry>,
+}
+
+impl Waker {
+    /// Creates a new `Waker`.
+    #[inline]
+    pub(crate) fn new() -> Self {
+        Waker { selectors: Vec::new(), observers: Vec::new() }
+    }
+
+    /// Registers a select operation.
+    #[inline]
+    pub(crate) fn register(&mut self, oper: Operation, cx: &Context) {
+        self.register_with_packet(oper, ptr::null_mut(), cx);
+    }
+
+    /// Registers a select operation and a packet.
+    #[inline]
+    pub(crate) fn register_with_packet(&mut self, oper: Operation, packet: *mut (), cx: &Context) {
+        self.selectors.push(Entry { oper, packet, cx: cx.clone() });
+    }
+
+    /// Unregisters a select operation.
+    #[inline]
+    pub(crate) fn unregister(&mut self, oper: Operation) -> Option<Entry> {
+        if let Some((i, _)) =
+            self.selectors.iter().enumerate().find(|&(_, entry)| entry.oper == oper)
+        {
+            let entry = self.selectors.remove(i);
+            Some(entry)
+        } else {
+            None
+        }
+    }
+
+    /// Attempts to find another thread's entry, select the operation, and wake it up.
+    #[inline]
+    pub(crate) fn try_select(&mut self) -> Option<Entry> {
+        self.selectors
+            .iter()
+            .position(|selector| {
+                // Does the entry belong to a different thread?
+                selector.cx.thread_id() != current_thread_id()
+                    && selector // Try selecting this operation.
+                        .cx
+                        .try_select(Selected::Operation(selector.oper))
+                        .is_ok()
+                    && {
+                        // Provide the packet.
+                        selector.cx.store_packet(selector.packet);
+                        // Wake the thread up.
+                        selector.cx.unpark();
+                        true
+                    }
+            })
+            // Remove the entry from the queue to keep it clean and improve
+            // performance.
+            .map(|pos| self.selectors.remove(pos))
+    }
+
+    /// Notifies all operations waiting to be ready.
+    #[inline]
+    pub(crate) fn notify(&mut self) {
+        for entry in self.observers.drain(..) {
+            if entry.cx.try_select(Selected::Operation(entry.oper)).is_ok() {
+                entry.cx.unpark();
+            }
+        }
+    }
+
+    /// Notifies all registered operations that the channel is disconnected.
+    #[inline]
+    pub(crate) fn disconnect(&mut self) {
+        for entry in self.selectors.iter() {
+            if entry.cx.try_select(Selected::Disconnected).is_ok() {
+                // Wake the thread up.
+                //
+                // Here we don't remove the entry from the queue. Registered threads must
+                // unregister from the waker by themselves. They might also want to recover the
+                // packet value and destroy it, if necessary.
+                entry.cx.unpark();
+            }
+        }
+
+        self.notify();
+    }
+}
+
+impl Drop for Waker {
+    #[inline]
+    fn drop(&mut self) {
+        debug_assert_eq!(self.selectors.len(), 0);
+        debug_assert_eq!(self.observers.len(), 0);
+    }
+}
+
+/// A waker that can be shared among threads without locking.
+///
+/// This is a simple wrapper around `Waker` that internally uses a mutex for synchronization.
+pub(crate) struct SyncWaker {
+    /// The inner `Waker`.
+    inner: Mutex<Waker>,
+
+    /// `true` if the waker is empty.
+    is_empty: AtomicBool,
+}
+
+impl SyncWaker {
+    /// Creates a new `SyncWaker`.
+    #[inline]
+    pub(crate) fn new() -> Self {
+        SyncWaker { inner: Mutex::new(Waker::new()), is_empty: AtomicBool::new(true) }
+    }
+
+    /// Registers the current thread with an operation.
+    #[inline]
+    pub(crate) fn register(&self, oper: Operation, cx: &Context) {
+        let mut inner = self.inner.lock().unwrap();
+        inner.register(oper, cx);
+        self.is_empty
+            .store(inner.selectors.is_empty() && inner.observers.is_empty(), Ordering::SeqCst);
+    }
+
+    /// Unregisters an operation previously registered by the current thread.
+    #[inline]
+    pub(crate) fn unregister(&self, oper: Operation) -> Option<Entry> {
+        let mut inner = self.inner.lock().unwrap();
+        let entry = inner.unregister(oper);
+        self.is_empty
+            .store(inner.selectors.is_empty() && inner.observers.is_empty(), Ordering::SeqCst);
+        entry
+    }
+
+    /// Attempts to find one thread (not the current one), select its operation, and wake it up.
+    #[inline]
+    pub(crate) fn notify(&self) {
+        if !self.is_empty.load(Ordering::SeqCst) {
+            let mut inner = self.inner.lock().unwrap();
+            if !self.is_empty.load(Ordering::SeqCst) {
+                inner.try_select();
+                inner.notify();
+                self.is_empty.store(
+                    inner.selectors.is_empty() && inner.observers.is_empty(),
+                    Ordering::SeqCst,
+                );
+            }
+        }
+    }
+
+    /// Notifies all threads that the channel is disconnected.
+    #[inline]
+    pub(crate) fn disconnect(&self) {
+        let mut inner = self.inner.lock().unwrap();
+        inner.disconnect();
+        self.is_empty
+            .store(inner.selectors.is_empty() && inner.observers.is_empty(), Ordering::SeqCst);
+    }
+}
+
+impl Drop for SyncWaker {
+    #[inline]
+    fn drop(&mut self) {
+        debug_assert!(self.is_empty.load(Ordering::SeqCst));
+    }
+}
+
+/// Returns a unique id for the current thread.
+#[inline]
+pub fn current_thread_id() -> usize {
+    // `u8` is not drop so this variable will be available during thread destruction,
+    // whereas `thread::current()` would not be
+    thread_local! { static DUMMY: u8 = 0 }
+    DUMMY.with(|x| (x as *const u8).addr())
+}
diff --git a/library/std/src/sync/mpmc/zero.rs b/library/std/src/sync/mpmc/zero.rs
new file mode 100644
index 000000000000..fccd6c29a7e4
--- /dev/null
+++ b/library/std/src/sync/mpmc/zero.rs
@@ -0,0 +1,318 @@
+//! Zero-capacity channel.
+//!
+//! This kind of channel is also known as *rendezvous* channel.
+
+use super::context::Context;
+use super::error::*;
+use super::select::{Operation, Selected, Token};
+use super::utils::Backoff;
+use super::waker::Waker;
+
+use crate::cell::UnsafeCell;
+use crate::marker::PhantomData;
+use crate::sync::atomic::{AtomicBool, Ordering};
+use crate::sync::Mutex;
+use crate::time::Instant;
+use crate::{fmt, ptr};
+
+/// A pointer to a packet.
+pub(crate) struct ZeroToken(*mut ());
+
+impl Default for ZeroToken {
+    fn default() -> Self {
+        Self(ptr::null_mut())
+    }
+}
+
+impl fmt::Debug for ZeroToken {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt::Debug::fmt(&(self.0 as usize), f)
+    }
+}
+
+/// A slot for passing one message from a sender to a receiver.
+struct Packet<T> {
+    /// Equals `true` if the packet is allocated on the stack.
+    on_stack: bool,
+
+    /// Equals `true` once the packet is ready for reading or writing.
+    ready: AtomicBool,
+
+    /// The message.
+    msg: UnsafeCell<Option<T>>,
+}
+
+impl<T> Packet<T> {
+    /// Creates an empty packet on the stack.
+    fn empty_on_stack() -> Packet<T> {
+        Packet { on_stack: true, ready: AtomicBool::new(false), msg: UnsafeCell::new(None) }
+    }
+
+    /// Creates a packet on the stack, containing a message.
+    fn message_on_stack(msg: T) -> Packet<T> {
+        Packet { on_stack: true, ready: AtomicBool::new(false), msg: UnsafeCell::new(Some(msg)) }
+    }
+
+    /// Waits until the packet becomes ready for reading or writing.
+    fn wait_ready(&self) {
+        let backoff = Backoff::new();
+        while !self.ready.load(Ordering::Acquire) {
+            backoff.snooze();
+        }
+    }
+}
+
+/// Inner representation of a zero-capacity channel.
+struct Inner {
+    /// Senders waiting to pair up with a receive operation.
+    senders: Waker,
+
+    /// Receivers waiting to pair up with a send operation.
+    receivers: Waker,
+
+    /// Equals `true` when the channel is disconnected.
+    is_disconnected: bool,
+}
+
+/// Zero-capacity channel.
+pub(crate) struct Channel<T> {
+    /// Inner representation of the channel.
+    inner: Mutex<Inner>,
+
+    /// Indicates that dropping a `Channel<T>` may drop values of type `T`.
+    _marker: PhantomData<T>,
+}
+
+impl<T> Channel<T> {
+    /// Constructs a new zero-capacity channel.
+    pub(crate) fn new() -> Self {
+        Channel {
+            inner: Mutex::new(Inner {
+                senders: Waker::new(),
+                receivers: Waker::new(),
+                is_disconnected: false,
+            }),
+            _marker: PhantomData,
+        }
+    }
+
+    /// Writes a message into the packet.
+    pub(crate) unsafe fn write(&self, token: &mut Token, msg: T) -> Result<(), T> {
+        // If there is no packet, the channel is disconnected.
+        if token.zero.0.is_null() {
+            return Err(msg);
+        }
+
+        let packet = &*(token.zero.0 as *const Packet<T>);
+        packet.msg.get().write(Some(msg));
+        packet.ready.store(true, Ordering::Release);
+        Ok(())
+    }
+
+    /// Reads a message from the packet.
+    pub(crate) unsafe fn read(&self, token: &mut Token) -> Result<T, ()> {
+        // If there is no packet, the channel is disconnected.
+        if token.zero.0.is_null() {
+            return Err(());
+        }
+
+        let packet = &*(token.zero.0 as *const Packet<T>);
+
+        if packet.on_stack {
+            // The message has been in the packet from the beginning, so there is no need to wait
+            // for it. However, after reading the message, we need to set `ready` to `true` in
+            // order to signal that the packet can be destroyed.
+            let msg = packet.msg.get().replace(None).unwrap();
+            packet.ready.store(true, Ordering::Release);
+            Ok(msg)
+        } else {
+            // Wait until the message becomes available, then read it and destroy the
+            // heap-allocated packet.
+            packet.wait_ready();
+            let msg = packet.msg.get().replace(None).unwrap();
+            drop(Box::from_raw(token.zero.0 as *mut Packet<T>));
+            Ok(msg)
+        }
+    }
+
+    /// Attempts to send a message into the channel.
+    pub(crate) fn try_send(&self, msg: T) -> Result<(), TrySendError<T>> {
+        let token = &mut Token::default();
+        let mut inner = self.inner.lock().unwrap();
+
+        // If there's a waiting receiver, pair up with it.
+        if let Some(operation) = inner.receivers.try_select() {
+            token.zero.0 = operation.packet;
+            drop(inner);
+            unsafe {
+                self.write(token, msg).ok().unwrap();
+            }
+            Ok(())
+        } else if inner.is_disconnected {
+            Err(TrySendError::Disconnected(msg))
+        } else {
+            Err(TrySendError::Full(msg))
+        }
+    }
+
+    /// Sends a message into the channel.
+    pub(crate) fn send(
+        &self,
+        msg: T,
+        deadline: Option<Instant>,
+    ) -> Result<(), SendTimeoutError<T>> {
+        let token = &mut Token::default();
+        let mut inner = self.inner.lock().unwrap();
+
+        // If there's a waiting receiver, pair up with it.
+        if let Some(operation) = inner.receivers.try_select() {
+            token.zero.0 = operation.packet;
+            drop(inner);
+            unsafe {
+                self.write(token, msg).ok().unwrap();
+            }
+            return Ok(());
+        }
+
+        if inner.is_disconnected {
+            return Err(SendTimeoutError::Disconnected(msg));
+        }
+
+        Context::with(|cx| {
+            // Prepare for blocking until a receiver wakes us up.
+            let oper = Operation::hook(token);
+            let mut packet = Packet::<T>::message_on_stack(msg);
+            inner.senders.register_with_packet(oper, &mut packet as *mut Packet<T> as *mut (), cx);
+            inner.receivers.notify();
+            drop(inner);
+
+            // Block the current thread.
+            let sel = cx.wait_until(deadline);
+
+            match sel {
+                Selected::Waiting => unreachable!(),
+                Selected::Aborted => {
+                    self.inner.lock().unwrap().senders.unregister(oper).unwrap();
+                    let msg = unsafe { packet.msg.get().replace(None).unwrap() };
+                    Err(SendTimeoutError::Timeout(msg))
+                }
+                Selected::Disconnected => {
+                    self.inner.lock().unwrap().senders.unregister(oper).unwrap();
+                    let msg = unsafe { packet.msg.get().replace(None).unwrap() };
+                    Err(SendTimeoutError::Disconnected(msg))
+                }
+                Selected::Operation(_) => {
+                    // Wait until the message is read, then drop the packet.
+                    packet.wait_ready();
+                    Ok(())
+                }
+            }
+        })
+    }
+
+    /// Attempts to receive a message without blocking.
+    pub(crate) fn try_recv(&self) -> Result<T, TryRecvError> {
+        let token = &mut Token::default();
+        let mut inner = self.inner.lock().unwrap();
+
+        // If there's a waiting sender, pair up with it.
+        if let Some(operation) = inner.senders.try_select() {
+            token.zero.0 = operation.packet;
+            drop(inner);
+            unsafe { self.read(token).map_err(|_| TryRecvError::Disconnected) }
+        } else if inner.is_disconnected {
+            Err(TryRecvError::Disconnected)
+        } else {
+            Err(TryRecvError::Empty)
+        }
+    }
+
+    /// Receives a message from the channel.
+    pub(crate) fn recv(&self, deadline: Option<Instant>) -> Result<T, RecvTimeoutError> {
+        let token = &mut Token::default();
+        let mut inner = self.inner.lock().unwrap();
+
+        // If there's a waiting sender, pair up with it.
+        if let Some(operation) = inner.senders.try_select() {
+            token.zero.0 = operation.packet;
+            drop(inner);
+            unsafe {
+                return self.read(token).map_err(|_| RecvTimeoutError::Disconnected);
+            }
+        }
+
+        if inner.is_disconnected {
+            return Err(RecvTimeoutError::Disconnected);
+        }
+
+        Context::with(|cx| {
+            // Prepare for blocking until a sender wakes us up.
+            let oper = Operation::hook(token);
+            let mut packet = Packet::<T>::empty_on_stack();
+            inner.receivers.register_with_packet(
+                oper,
+                &mut packet as *mut Packet<T> as *mut (),
+                cx,
+            );
+            inner.senders.notify();
+            drop(inner);
+
+            // Block the current thread.
+            let sel = cx.wait_until(deadline);
+
+            match sel {
+                Selected::Waiting => unreachable!(),
+                Selected::Aborted => {
+                    self.inner.lock().unwrap().receivers.unregister(oper).unwrap();
+                    Err(RecvTimeoutError::Timeout)
+                }
+                Selected::Disconnected => {
+                    self.inner.lock().unwrap().receivers.unregister(oper).unwrap();
+                    Err(RecvTimeoutError::Disconnected)
+                }
+                Selected::Operation(_) => {
+                    // Wait until the message is provided, then read it.
+                    packet.wait_ready();
+                    unsafe { Ok(packet.msg.get().replace(None).unwrap()) }
+                }
+            }
+        })
+    }
+
+    /// Disconnects the channel and wakes up all blocked senders and receivers.
+    ///
+    /// Returns `true` if this call disconnected the channel.
+    pub(crate) fn disconnect(&self) -> bool {
+        let mut inner = self.inner.lock().unwrap();
+
+        if !inner.is_disconnected {
+            inner.is_disconnected = true;
+            inner.senders.disconnect();
+            inner.receivers.disconnect();
+            true
+        } else {
+            false
+        }
+    }
+
+    /// Returns the current number of messages inside the channel.
+    pub(crate) fn len(&self) -> usize {
+        0
+    }
+
+    /// Returns the capacity of the channel.
+    #[allow(clippy::unnecessary_wraps)] // This is intentional.
+    pub(crate) fn capacity(&self) -> Option<usize> {
+        Some(0)
+    }
+
+    /// Returns `true` if the channel is empty.
+    pub(crate) fn is_empty(&self) -> bool {
+        true
+    }
+
+    /// Returns `true` if the channel is full.
+    pub(crate) fn is_full(&self) -> bool {
+        true
+    }
+}
diff --git a/library/std/src/sync/mpsc/blocking.rs b/library/std/src/sync/mpsc/blocking.rs
deleted file mode 100644
index 021df7b096cb..000000000000
--- a/library/std/src/sync/mpsc/blocking.rs
+++ /dev/null
@@ -1,82 +0,0 @@
-//! Generic support for building blocking abstractions.
-
-use crate::sync::atomic::{AtomicBool, Ordering};
-use crate::sync::Arc;
-use crate::thread::{self, Thread};
-use crate::time::Instant;
-
-struct Inner {
-    thread: Thread,
-    woken: AtomicBool,
-}
-
-unsafe impl Send for Inner {}
-unsafe impl Sync for Inner {}
-
-#[derive(Clone)]
-pub struct SignalToken {
-    inner: Arc<Inner>,
-}
-
-pub struct WaitToken {
-    inner: Arc<Inner>,
-}
-
-impl !Send for WaitToken {}
-
-impl !Sync for WaitToken {}
-
-pub fn tokens() -> (WaitToken, SignalToken) {
-    let inner = Arc::new(Inner { thread: thread::current(), woken: AtomicBool::new(false) });
-    let wait_token = WaitToken { inner: inner.clone() };
-    let signal_token = SignalToken { inner };
-    (wait_token, signal_token)
-}
-
-impl SignalToken {
-    pub fn signal(&self) -> bool {
-        let wake = self
-            .inner
-            .woken
-            .compare_exchange(false, true, Ordering::SeqCst, Ordering::SeqCst)
-            .is_ok();
-        if wake {
-            self.inner.thread.unpark();
-        }
-        wake
-    }
-
-    /// Converts to an unsafe raw pointer. Useful for storing in a pipe's state
-    /// flag.
-    #[inline]
-    pub unsafe fn to_raw(self) -> *mut u8 {
-        Arc::into_raw(self.inner) as *mut u8
-    }
-
-    /// Converts from an unsafe raw pointer. Useful for retrieving a pipe's state
-    /// flag.
-    #[inline]
-    pub unsafe fn from_raw(signal_ptr: *mut u8) -> SignalToken {
-        SignalToken { inner: Arc::from_raw(signal_ptr as *mut Inner) }
-    }
-}
-
-impl WaitToken {
-    pub fn wait(self) {
-        while !self.inner.woken.load(Ordering::SeqCst) {
-            thread::park()
-        }
-    }
-
-    /// Returns `true` if we wake up normally.
-    pub fn wait_max_until(self, end: Instant) -> bool {
-        while !self.inner.woken.load(Ordering::SeqCst) {
-            let now = Instant::now();
-            if now >= end {
-                return false;
-            }
-            thread::park_timeout(end - now)
-        }
-        true
-    }
-}
diff --git a/library/std/src/sync/mpsc/cache_aligned.rs b/library/std/src/sync/mpsc/cache_aligned.rs
deleted file mode 100644
index 9197f0d6e6c8..000000000000
--- a/library/std/src/sync/mpsc/cache_aligned.rs
+++ /dev/null
@@ -1,25 +0,0 @@
-use crate::ops::{Deref, DerefMut};
-
-#[derive(Copy, Clone, Default, PartialEq, Eq, PartialOrd, Ord, Hash)]
-#[cfg_attr(target_arch = "aarch64", repr(align(128)))]
-#[cfg_attr(not(target_arch = "aarch64"), repr(align(64)))]
-pub(super) struct CacheAligned<T>(pub T);
-
-impl<T> Deref for CacheAligned<T> {
-    type Target = T;
-    fn deref(&self) -> &Self::Target {
-        &self.0
-    }
-}
-
-impl<T> DerefMut for CacheAligned<T> {
-    fn deref_mut(&mut self) -> &mut Self::Target {
-        &mut self.0
-    }
-}
-
-impl<T> CacheAligned<T> {
-    pub(super) fn new(t: T) -> Self {
-        CacheAligned(t)
-    }
-}
diff --git a/library/std/src/sync/mpsc/mod.rs b/library/std/src/sync/mpsc/mod.rs
index e85a87239651..27fba761ada1 100644
--- a/library/std/src/sync/mpsc/mod.rs
+++ b/library/std/src/sync/mpsc/mod.rs
@@ -143,175 +143,16 @@ mod tests;
 #[cfg(all(test, not(target_os = "emscripten")))]
 mod sync_tests;
 
-// A description of how Rust's channel implementation works
-//
-// Channels are supposed to be the basic building block for all other
-// concurrent primitives that are used in Rust. As a result, the channel type
-// needs to be highly optimized, flexible, and broad enough for use everywhere.
-//
-// The choice of implementation of all channels is to be built on lock-free data
-// structures. The channels themselves are then consequently also lock-free data
-// structures. As always with lock-free code, this is a very "here be dragons"
-// territory, especially because I'm unaware of any academic papers that have
-// gone into great length about channels of these flavors.
-//
-// ## Flavors of channels
-//
-// From the perspective of a consumer of this library, there is only one flavor
-// of channel. This channel can be used as a stream and cloned to allow multiple
-// senders. Under the hood, however, there are actually three flavors of
-// channels in play.
-//
-// * Flavor::Oneshots - these channels are highly optimized for the one-send use
-//                      case. They contain as few atomics as possible and
-//                      involve one and exactly one allocation.
-// * Streams - these channels are optimized for the non-shared use case. They
-//             use a different concurrent queue that is more tailored for this
-//             use case. The initial allocation of this flavor of channel is not
-//             optimized.
-// * Shared - this is the most general form of channel that this module offers,
-//            a channel with multiple senders. This type is as optimized as it
-//            can be, but the previous two types mentioned are much faster for
-//            their use-cases.
-//
-// ## Concurrent queues
-//
-// The basic idea of Rust's Sender/Receiver types is that send() never blocks,
-// but recv() obviously blocks. This means that under the hood there must be
-// some shared and concurrent queue holding all of the actual data.
-//
-// With two flavors of channels, two flavors of queues are also used. We have
-// chosen to use queues from a well-known author that are abbreviated as SPSC
-// and MPSC (single producer, single consumer and multiple producer, single
-// consumer). SPSC queues are used for streams while MPSC queues are used for
-// shared channels.
-//
-// ### SPSC optimizations
-//
-// The SPSC queue found online is essentially a linked list of nodes where one
-// half of the nodes are the "queue of data" and the other half of nodes are a
-// cache of unused nodes. The unused nodes are used such that an allocation is
-// not required on every push() and a free doesn't need to happen on every
-// pop().
-//
-// As found online, however, the cache of nodes is of an infinite size. This
-// means that if a channel at one point in its life had 50k items in the queue,
-// then the queue will always have the capacity for 50k items. I believed that
-// this was an unnecessary limitation of the implementation, so I have altered
-// the queue to optionally have a bound on the cache size.
-//
-// By default, streams will have an unbounded SPSC queue with a small-ish cache
-// size. The hope is that the cache is still large enough to have very fast
-// send() operations while not too large such that millions of channels can
-// coexist at once.
-//
-// ### MPSC optimizations
-//
-// Right now the MPSC queue has not been optimized. Like the SPSC queue, it uses
-// a linked list under the hood to earn its unboundedness, but I have not put
-// forth much effort into having a cache of nodes similar to the SPSC queue.
-//
-// For now, I believe that this is "ok" because shared channels are not the most
-// common type, but soon we may wish to revisit this queue choice and determine
-// another candidate for backend storage of shared channels.
-//
-// ## Overview of the Implementation
-//
-// Now that there's a little background on the concurrent queues used, it's
-// worth going into much more detail about the channels themselves. The basic
-// pseudocode for a send/recv are:
-//
-//
-//      send(t)                             recv()
-//        queue.push(t)                       return if queue.pop()
-//        if increment() == -1                deschedule {
-//          wakeup()                            if decrement() > 0
-//                                                cancel_deschedule()
-//                                            }
-//                                            queue.pop()
-//
-// As mentioned before, there are no locks in this implementation, only atomic
-// instructions are used.
-//
-// ### The internal atomic counter
-//
-// Every channel has a shared counter with each half to keep track of the size
-// of the queue. This counter is used to abort descheduling by the receiver and
-// to know when to wake up on the sending side.
-//
-// As seen in the pseudocode, senders will increment this count and receivers
-// will decrement the count. The theory behind this is that if a sender sees a
-// -1 count, it will wake up the receiver, and if the receiver sees a 1+ count,
-// then it doesn't need to block.
-//
-// The recv() method has a beginning call to pop(), and if successful, it needs
-// to decrement the count. It is a crucial implementation detail that this
-// decrement does *not* happen to the shared counter. If this were the case,
-// then it would be possible for the counter to be very negative when there were
-// no receivers waiting, in which case the senders would have to determine when
-// it was actually appropriate to wake up a receiver.
-//
-// Instead, the "steal count" is kept track of separately (not atomically
-// because it's only used by receivers), and then the decrement() call when
-// descheduling will lump in all of the recent steals into one large decrement.
-//
-// The implication of this is that if a sender sees a -1 count, then there's
-// guaranteed to be a waiter waiting!
-//
-// ## Native Implementation
-//
-// A major goal of these channels is to work seamlessly on and off the runtime.
-// All of the previous race conditions have been worded in terms of
-// scheduler-isms (which is obviously not available without the runtime).
-//
-// For now, native usage of channels (off the runtime) will fall back onto
-// mutexes/cond vars for descheduling/atomic decisions. The no-contention path
-// is still entirely lock-free, the "deschedule" blocks above are surrounded by
-// a mutex and the "wakeup" blocks involve grabbing a mutex and signaling on a
-// condition variable.
-//
-// ## Select
-//
-// Being able to support selection over channels has greatly influenced this
-// design, and not only does selection need to work inside the runtime, but also
-// outside the runtime.
-//
-// The implementation is fairly straightforward. The goal of select() is not to
-// return some data, but only to return which channel can receive data without
-// blocking. The implementation is essentially the entire blocking procedure
-// followed by an increment as soon as its woken up. The cancellation procedure
-// involves an increment and swapping out of to_wake to acquire ownership of the
-// thread to unblock.
-//
-// Sadly this current implementation requires multiple allocations, so I have
-// seen the throughput of select() be much worse than it should be. I do not
-// believe that there is anything fundamental that needs to change about these
-// channels, however, in order to support a more efficient select().
-//
-// FIXME: Select is now removed, so these factors are ready to be cleaned up!
-//
-// # Conclusion
-//
-// And now that you've seen all the races that I found and attempted to fix,
-// here's the code for you to find some more!
+// MPSC channels are built as a wrapper around MPMC channels, which
+// were ported from the `crossbeam-channel` crate. MPMC channels are
+// not exposed publicly, but if you are curious about the implementation,
+// that's where everything is.
 
-use crate::cell::UnsafeCell;
 use crate::error;
 use crate::fmt;
-use crate::mem;
-use crate::sync::Arc;
+use crate::sync::mpmc;
 use crate::time::{Duration, Instant};
 
-mod blocking;
-mod mpsc_queue;
-mod oneshot;
-mod shared;
-mod spsc_queue;
-mod stream;
-mod sync;
-
-mod cache_aligned;
-
 /// The receiving half of Rust's [`channel`] (or [`sync_channel`]) type.
 /// This half can only be owned by one thread.
 ///
@@ -341,7 +182,7 @@ mod cache_aligned;
 #[stable(feature = "rust1", since = "1.0.0")]
 #[cfg_attr(not(test), rustc_diagnostic_item = "Receiver")]
 pub struct Receiver<T> {
-    inner: UnsafeCell<Flavor<T>>,
+    inner: mpmc::Receiver<T>,
 }
 
 // The receiver port can be sent from place to place, so long as it
@@ -498,7 +339,7 @@ pub struct IntoIter<T> {
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 pub struct Sender<T> {
-    inner: UnsafeCell<Flavor<T>>,
+    inner: mpmc::Sender<T>,
 }
 
 // The send port can be sent from place to place, so long as it
@@ -557,7 +398,7 @@ impl<T> !Sync for Sender<T> {}
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 pub struct SyncSender<T> {
-    inner: Arc<sync::Packet<T>>,
+    inner: mpmc::Sender<T>,
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
@@ -643,34 +484,6 @@ pub enum TrySendError<T> {
     Disconnected(#[stable(feature = "rust1", since = "1.0.0")] T),
 }
 
-enum Flavor<T> {
-    Oneshot(Arc<oneshot::Packet<T>>),
-    Stream(Arc<stream::Packet<T>>),
-    Shared(Arc<shared::Packet<T>>),
-    Sync(Arc<sync::Packet<T>>),
-}
-
-#[doc(hidden)]
-trait UnsafeFlavor<T> {
-    fn inner_unsafe(&self) -> &UnsafeCell<Flavor<T>>;
-    unsafe fn inner_mut(&self) -> &mut Flavor<T> {
-        &mut *self.inner_unsafe().get()
-    }
-    unsafe fn inner(&self) -> &Flavor<T> {
-        &*self.inner_unsafe().get()
-    }
-}
-impl<T> UnsafeFlavor<T> for Sender<T> {
-    fn inner_unsafe(&self) -> &UnsafeCell<Flavor<T>> {
-        &self.inner
-    }
-}
-impl<T> UnsafeFlavor<T> for Receiver<T> {
-    fn inner_unsafe(&self) -> &UnsafeCell<Flavor<T>> {
-        &self.inner
-    }
-}
-
 /// Creates a new asynchronous channel, returning the sender/receiver halves.
 /// All data sent on the [`Sender`] will become available on the [`Receiver`] in
 /// the same order as it was sent, and no [`send`] will block the calling thread
@@ -711,8 +524,8 @@ impl<T> UnsafeFlavor<T> for Receiver<T> {
 #[must_use]
 #[stable(feature = "rust1", since = "1.0.0")]
 pub fn channel<T>() -> (Sender<T>, Receiver<T>) {
-    let a = Arc::new(oneshot::Packet::new());
-    (Sender::new(Flavor::Oneshot(a.clone())), Receiver::new(Flavor::Oneshot(a)))
+    let (tx, rx) = mpmc::channel();
+    (Sender { inner: tx }, Receiver { inner: rx })
 }
 
 /// Creates a new synchronous, bounded channel.
@@ -760,8 +573,8 @@ pub fn channel<T>() -> (Sender<T>, Receiver<T>) {
 #[must_use]
 #[stable(feature = "rust1", since = "1.0.0")]
 pub fn sync_channel<T>(bound: usize) -> (SyncSender<T>, Receiver<T>) {
-    let a = Arc::new(sync::Packet::new(bound));
-    (SyncSender::new(a.clone()), Receiver::new(Flavor::Sync(a)))
+    let (tx, rx) = mpmc::sync_channel(bound);
+    (SyncSender { inner: tx }, Receiver { inner: rx })
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -769,10 +582,6 @@ pub fn sync_channel<T>(bound: usize) -> (SyncSender<T>, Receiver<T>) {
 ////////////////////////////////////////////////////////////////////////////////
 
 impl<T> Sender<T> {
-    fn new(inner: Flavor<T>) -> Sender<T> {
-        Sender { inner: UnsafeCell::new(inner) }
-    }
-
     /// Attempts to send a value on this channel, returning it back if it could
     /// not be sent.
     ///
@@ -802,40 +611,7 @@ impl<T> Sender<T> {
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn send(&self, t: T) -> Result<(), SendError<T>> {
-        let (new_inner, ret) = match *unsafe { self.inner() } {
-            Flavor::Oneshot(ref p) => {
-                if !p.sent() {
-                    return p.send(t).map_err(SendError);
-                } else {
-                    let a = Arc::new(stream::Packet::new());
-                    let rx = Receiver::new(Flavor::Stream(a.clone()));
-                    match p.upgrade(rx) {
-                        oneshot::UpSuccess => {
-                            let ret = a.send(t);
-                            (a, ret)
-                        }
-                        oneshot::UpDisconnected => (a, Err(t)),
-                        oneshot::UpWoke(token) => {
-                            // This send cannot panic because the thread is
-                            // asleep (we're looking at it), so the receiver
-                            // can't go away.
-                            a.send(t).ok().unwrap();
-                            token.signal();
-                            (a, Ok(()))
-                        }
-                    }
-                }
-            }
-            Flavor::Stream(ref p) => return p.send(t).map_err(SendError),
-            Flavor::Shared(ref p) => return p.send(t).map_err(SendError),
-            Flavor::Sync(..) => unreachable!(),
-        };
-
-        unsafe {
-            let tmp = Sender::new(Flavor::Stream(new_inner));
-            mem::swap(self.inner_mut(), tmp.inner_mut());
-        }
-        ret.map_err(SendError)
+        self.inner.send(t)
     }
 }
 
@@ -847,57 +623,14 @@ impl<T> Clone for Sender<T> {
     /// (including the original) need to be dropped in order for
     /// [`Receiver::recv`] to stop blocking.
     fn clone(&self) -> Sender<T> {
-        let packet = match *unsafe { self.inner() } {
-            Flavor::Oneshot(ref p) => {
-                let a = Arc::new(shared::Packet::new());
-                {
-                    let guard = a.postinit_lock();
-                    let rx = Receiver::new(Flavor::Shared(a.clone()));
-                    let sleeper = match p.upgrade(rx) {
-                        oneshot::UpSuccess | oneshot::UpDisconnected => None,
-                        oneshot::UpWoke(task) => Some(task),
-                    };
-                    a.inherit_blocker(sleeper, guard);
-                }
-                a
-            }
-            Flavor::Stream(ref p) => {
-                let a = Arc::new(shared::Packet::new());
-                {
-                    let guard = a.postinit_lock();
-                    let rx = Receiver::new(Flavor::Shared(a.clone()));
-                    let sleeper = match p.upgrade(rx) {
-                        stream::UpSuccess | stream::UpDisconnected => None,
-                        stream::UpWoke(task) => Some(task),
-                    };
-                    a.inherit_blocker(sleeper, guard);
-                }
-                a
-            }
-            Flavor::Shared(ref p) => {
-                p.clone_chan();
-                return Sender::new(Flavor::Shared(p.clone()));
-            }
-            Flavor::Sync(..) => unreachable!(),
-        };
-
-        unsafe {
-            let tmp = Sender::new(Flavor::Shared(packet.clone()));
-            mem::swap(self.inner_mut(), tmp.inner_mut());
-        }
-        Sender::new(Flavor::Shared(packet))
+        Sender { inner: self.inner.clone() }
     }
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<T> Drop for Sender<T> {
     fn drop(&mut self) {
-        match *unsafe { self.inner() } {
-            Flavor::Oneshot(ref p) => p.drop_chan(),
-            Flavor::Stream(ref p) => p.drop_chan(),
-            Flavor::Shared(ref p) => p.drop_chan(),
-            Flavor::Sync(..) => unreachable!(),
-        }
+        let _ = self.inner;
     }
 }
 
@@ -913,10 +646,6 @@ impl<T> fmt::Debug for Sender<T> {
 ////////////////////////////////////////////////////////////////////////////////
 
 impl<T> SyncSender<T> {
-    fn new(inner: Arc<sync::Packet<T>>) -> SyncSender<T> {
-        SyncSender { inner }
-    }
-
     /// Sends a value on this synchronous channel.
     ///
     /// This function will *block* until space in the internal buffer becomes
@@ -955,7 +684,7 @@ impl<T> SyncSender<T> {
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn send(&self, t: T) -> Result<(), SendError<T>> {
-        self.inner.send(t).map_err(SendError)
+        self.inner.send(t)
     }
 
     /// Attempts to send a value on this channel without blocking.
@@ -1016,15 +745,14 @@ impl<T> SyncSender<T> {
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<T> Clone for SyncSender<T> {
     fn clone(&self) -> SyncSender<T> {
-        self.inner.clone_chan();
-        SyncSender::new(self.inner.clone())
+        SyncSender { inner: self.inner.clone() }
     }
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<T> Drop for SyncSender<T> {
     fn drop(&mut self) {
-        self.inner.drop_chan();
+        let _ = self.inner;
     }
 }
 
@@ -1040,10 +768,6 @@ impl<T> fmt::Debug for SyncSender<T> {
 ////////////////////////////////////////////////////////////////////////////////
 
 impl<T> Receiver<T> {
-    fn new(inner: Flavor<T>) -> Receiver<T> {
-        Receiver { inner: UnsafeCell::new(inner) }
-    }
-
     /// Attempts to return a pending value on this receiver without blocking.
     ///
     /// This method will never block the caller in order to wait for data to
@@ -1069,35 +793,7 @@ impl<T> Receiver<T> {
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn try_recv(&self) -> Result<T, TryRecvError> {
-        loop {
-            let new_port = match *unsafe { self.inner() } {
-                Flavor::Oneshot(ref p) => match p.try_recv() {
-                    Ok(t) => return Ok(t),
-                    Err(oneshot::Empty) => return Err(TryRecvError::Empty),
-                    Err(oneshot::Disconnected) => return Err(TryRecvError::Disconnected),
-                    Err(oneshot::Upgraded(rx)) => rx,
-                },
-                Flavor::Stream(ref p) => match p.try_recv() {
-                    Ok(t) => return Ok(t),
-                    Err(stream::Empty) => return Err(TryRecvError::Empty),
-                    Err(stream::Disconnected) => return Err(TryRecvError::Disconnected),
-                    Err(stream::Upgraded(rx)) => rx,
-                },
-                Flavor::Shared(ref p) => match p.try_recv() {
-                    Ok(t) => return Ok(t),
-                    Err(shared::Empty) => return Err(TryRecvError::Empty),
-                    Err(shared::Disconnected) => return Err(TryRecvError::Disconnected),
-                },
-                Flavor::Sync(ref p) => match p.try_recv() {
-                    Ok(t) => return Ok(t),
-                    Err(sync::Empty) => return Err(TryRecvError::Empty),
-                    Err(sync::Disconnected) => return Err(TryRecvError::Disconnected),
-                },
-            };
-            unsafe {
-                mem::swap(self.inner_mut(), new_port.inner_mut());
-            }
-        }
+        self.inner.try_recv()
     }
 
     /// Attempts to wait for a value on this receiver, returning an error if the
@@ -1156,31 +852,7 @@ impl<T> Receiver<T> {
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn recv(&self) -> Result<T, RecvError> {
-        loop {
-            let new_port = match *unsafe { self.inner() } {
-                Flavor::Oneshot(ref p) => match p.recv(None) {
-                    Ok(t) => return Ok(t),
-                    Err(oneshot::Disconnected) => return Err(RecvError),
-                    Err(oneshot::Upgraded(rx)) => rx,
-                    Err(oneshot::Empty) => unreachable!(),
-                },
-                Flavor::Stream(ref p) => match p.recv(None) {
-                    Ok(t) => return Ok(t),
-                    Err(stream::Disconnected) => return Err(RecvError),
-                    Err(stream::Upgraded(rx)) => rx,
-                    Err(stream::Empty) => unreachable!(),
-                },
-                Flavor::Shared(ref p) => match p.recv(None) {
-                    Ok(t) => return Ok(t),
-                    Err(shared::Disconnected) => return Err(RecvError),
-                    Err(shared::Empty) => unreachable!(),
-                },
-                Flavor::Sync(ref p) => return p.recv(None).map_err(|_| RecvError),
-            };
-            unsafe {
-                mem::swap(self.inner_mut(), new_port.inner_mut());
-            }
-        }
+        self.inner.recv()
     }
 
     /// Attempts to wait for a value on this receiver, returning an error if the
@@ -1198,34 +870,6 @@ impl<T> Receiver<T> {
     /// However, since channels are buffered, messages sent before the disconnect
     /// will still be properly received.
     ///
-    /// # Known Issues
-    ///
-    /// There is currently a known issue (see [`#39364`]) that causes `recv_timeout`
-    /// to panic unexpectedly with the following example:
-    ///
-    /// ```no_run
-    /// use std::sync::mpsc::channel;
-    /// use std::thread;
-    /// use std::time::Duration;
-    ///
-    /// let (tx, rx) = channel::<String>();
-    ///
-    /// thread::spawn(move || {
-    ///     let d = Duration::from_millis(10);
-    ///     loop {
-    ///         println!("recv");
-    ///         let _r = rx.recv_timeout(d);
-    ///     }
-    /// });
-    ///
-    /// thread::sleep(Duration::from_millis(100));
-    /// let _c1 = tx.clone();
-    ///
-    /// thread::sleep(Duration::from_secs(1));
-    /// ```
-    ///
-    /// [`#39364`]: https://github.com/rust-lang/rust/issues/39364
-    ///
     /// # Examples
     ///
     /// Successfully receiving value before encountering timeout:
@@ -1268,17 +912,7 @@ impl<T> Receiver<T> {
     /// ```
     #[stable(feature = "mpsc_recv_timeout", since = "1.12.0")]
     pub fn recv_timeout(&self, timeout: Duration) -> Result<T, RecvTimeoutError> {
-        // Do an optimistic try_recv to avoid the performance impact of
-        // Instant::now() in the full-channel case.
-        match self.try_recv() {
-            Ok(result) => Ok(result),
-            Err(TryRecvError::Disconnected) => Err(RecvTimeoutError::Disconnected),
-            Err(TryRecvError::Empty) => match Instant::now().checked_add(timeout) {
-                Some(deadline) => self.recv_deadline(deadline),
-                // So far in the future that it's practically the same as waiting indefinitely.
-                None => self.recv().map_err(RecvTimeoutError::from),
-            },
-        }
+        self.inner.recv_timeout(timeout)
     }
 
     /// Attempts to wait for a value on this receiver, returning an error if the
@@ -1339,46 +973,7 @@ impl<T> Receiver<T> {
     /// ```
     #[unstable(feature = "deadline_api", issue = "46316")]
     pub fn recv_deadline(&self, deadline: Instant) -> Result<T, RecvTimeoutError> {
-        use self::RecvTimeoutError::*;
-
-        loop {
-            let port_or_empty = match *unsafe { self.inner() } {
-                Flavor::Oneshot(ref p) => match p.recv(Some(deadline)) {
-                    Ok(t) => return Ok(t),
-                    Err(oneshot::Disconnected) => return Err(Disconnected),
-                    Err(oneshot::Upgraded(rx)) => Some(rx),
-                    Err(oneshot::Empty) => None,
-                },
-                Flavor::Stream(ref p) => match p.recv(Some(deadline)) {
-                    Ok(t) => return Ok(t),
-                    Err(stream::Disconnected) => return Err(Disconnected),
-                    Err(stream::Upgraded(rx)) => Some(rx),
-                    Err(stream::Empty) => None,
-                },
-                Flavor::Shared(ref p) => match p.recv(Some(deadline)) {
-                    Ok(t) => return Ok(t),
-                    Err(shared::Disconnected) => return Err(Disconnected),
-                    Err(shared::Empty) => None,
-                },
-                Flavor::Sync(ref p) => match p.recv(Some(deadline)) {
-                    Ok(t) => return Ok(t),
-                    Err(sync::Disconnected) => return Err(Disconnected),
-                    Err(sync::Empty) => None,
-                },
-            };
-
-            if let Some(new_port) = port_or_empty {
-                unsafe {
-                    mem::swap(self.inner_mut(), new_port.inner_mut());
-                }
-            }
-
-            // If we're already passed the deadline, and we're here without
-            // data, return a timeout, else try again.
-            if Instant::now() >= deadline {
-                return Err(Timeout);
-            }
-        }
+        self.inner.recv_deadline(deadline)
     }
 
     /// Returns an iterator that will block waiting for messages, but never
@@ -1500,12 +1095,7 @@ impl<T> IntoIterator for Receiver<T> {
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<T> Drop for Receiver<T> {
     fn drop(&mut self) {
-        match *unsafe { self.inner() } {
-            Flavor::Oneshot(ref p) => p.drop_port(),
-            Flavor::Stream(ref p) => p.drop_port(),
-            Flavor::Shared(ref p) => p.drop_port(),
-            Flavor::Sync(ref p) => p.drop_port(),
-        }
+        let _ = self.inner;
     }
 }
 
diff --git a/library/std/src/sync/mpsc/mpsc_queue.rs b/library/std/src/sync/mpsc/mpsc_queue.rs
deleted file mode 100644
index cdd64a5def50..000000000000
--- a/library/std/src/sync/mpsc/mpsc_queue.rs
+++ /dev/null
@@ -1,117 +0,0 @@
-//! A mostly lock-free multi-producer, single consumer queue.
-//!
-//! This module contains an implementation of a concurrent MPSC queue. This
-//! queue can be used to share data between threads, and is also used as the
-//! building block of channels in rust.
-//!
-//! Note that the current implementation of this queue has a caveat of the `pop`
-//! method, and see the method for more information about it. Due to this
-//! caveat, this queue might not be appropriate for all use-cases.
-
-// https://www.1024cores.net/home/lock-free-algorithms
-//                          /queues/non-intrusive-mpsc-node-based-queue
-
-#[cfg(all(test, not(target_os = "emscripten")))]
-mod tests;
-
-pub use self::PopResult::*;
-
-use core::cell::UnsafeCell;
-use core::ptr;
-
-use crate::boxed::Box;
-use crate::sync::atomic::{AtomicPtr, Ordering};
-
-/// A result of the `pop` function.
-pub enum PopResult<T> {
-    /// Some data has been popped
-    Data(T),
-    /// The queue is empty
-    Empty,
-    /// The queue is in an inconsistent state. Popping data should succeed, but
-    /// some pushers have yet to make enough progress in order allow a pop to
-    /// succeed. It is recommended that a pop() occur "in the near future" in
-    /// order to see if the sender has made progress or not
-    Inconsistent,
-}
-
-struct Node<T> {
-    next: AtomicPtr<Node<T>>,
-    value: Option<T>,
-}
-
-/// The multi-producer single-consumer structure. This is not cloneable, but it
-/// may be safely shared so long as it is guaranteed that there is only one
-/// popper at a time (many pushers are allowed).
-pub struct Queue<T> {
-    head: AtomicPtr<Node<T>>,
-    tail: UnsafeCell<*mut Node<T>>,
-}
-
-unsafe impl<T: Send> Send for Queue<T> {}
-unsafe impl<T: Send> Sync for Queue<T> {}
-
-impl<T> Node<T> {
-    unsafe fn new(v: Option<T>) -> *mut Node<T> {
-        Box::into_raw(box Node { next: AtomicPtr::new(ptr::null_mut()), value: v })
-    }
-}
-
-impl<T> Queue<T> {
-    /// Creates a new queue that is safe to share among multiple producers and
-    /// one consumer.
-    pub fn new() -> Queue<T> {
-        let stub = unsafe { Node::new(None) };
-        Queue { head: AtomicPtr::new(stub), tail: UnsafeCell::new(stub) }
-    }
-
-    /// Pushes a new value onto this queue.
-    pub fn push(&self, t: T) {
-        unsafe {
-            let n = Node::new(Some(t));
-            let prev = self.head.swap(n, Ordering::AcqRel);
-            (*prev).next.store(n, Ordering::Release);
-        }
-    }
-
-    /// Pops some data from this queue.
-    ///
-    /// Note that the current implementation means that this function cannot
-    /// return `Option<T>`. It is possible for this queue to be in an
-    /// inconsistent state where many pushes have succeeded and completely
-    /// finished, but pops cannot return `Some(t)`. This inconsistent state
-    /// happens when a pusher is pre-empted at an inopportune moment.
-    ///
-    /// This inconsistent state means that this queue does indeed have data, but
-    /// it does not currently have access to it at this time.
-    pub fn pop(&self) -> PopResult<T> {
-        unsafe {
-            let tail = *self.tail.get();
-            let next = (*tail).next.load(Ordering::Acquire);
-
-            if !next.is_null() {
-                *self.tail.get() = next;
-                assert!((*tail).value.is_none());
-                assert!((*next).value.is_some());
-                let ret = (*next).value.take().unwrap();
-                let _: Box<Node<T>> = Box::from_raw(tail);
-                return Data(ret);
-            }
-
-            if self.head.load(Ordering::Acquire) == tail { Empty } else { Inconsistent }
-        }
-    }
-}
-
-impl<T> Drop for Queue<T> {
-    fn drop(&mut self) {
-        unsafe {
-            let mut cur = *self.tail.get();
-            while !cur.is_null() {
-                let next = (*cur).next.load(Ordering::Relaxed);
-                let _: Box<Node<T>> = Box::from_raw(cur);
-                cur = next;
-            }
-        }
-    }
-}
diff --git a/library/std/src/sync/mpsc/mpsc_queue/tests.rs b/library/std/src/sync/mpsc/mpsc_queue/tests.rs
deleted file mode 100644
index 34b2a9a98ac3..000000000000
--- a/library/std/src/sync/mpsc/mpsc_queue/tests.rs
+++ /dev/null
@@ -1,47 +0,0 @@
-use super::{Data, Empty, Inconsistent, Queue};
-use crate::sync::mpsc::channel;
-use crate::sync::Arc;
-use crate::thread;
-
-#[test]
-fn test_full() {
-    let q: Queue<Box<_>> = Queue::new();
-    q.push(Box::new(1));
-    q.push(Box::new(2));
-}
-
-#[test]
-fn test() {
-    let nthreads = 8;
-    let nmsgs = if cfg!(miri) { 100 } else { 1000 };
-    let q = Queue::new();
-    match q.pop() {
-        Empty => {}
-        Inconsistent | Data(..) => panic!(),
-    }
-    let (tx, rx) = channel();
-    let q = Arc::new(q);
-
-    for _ in 0..nthreads {
-        let tx = tx.clone();
-        let q = q.clone();
-        thread::spawn(move || {
-            for i in 0..nmsgs {
-                q.push(i);
-            }
-            tx.send(()).unwrap();
-        });
-    }
-
-    let mut i = 0;
-    while i < nthreads * nmsgs {
-        match q.pop() {
-            Empty | Inconsistent => {}
-            Data(_) => i += 1,
-        }
-    }
-    drop(tx);
-    for _ in 0..nthreads {
-        rx.recv().unwrap();
-    }
-}
diff --git a/library/std/src/sync/mpsc/oneshot.rs b/library/std/src/sync/mpsc/oneshot.rs
deleted file mode 100644
index 0e259b8aecb9..000000000000
--- a/library/std/src/sync/mpsc/oneshot.rs
+++ /dev/null
@@ -1,315 +0,0 @@
-/// Oneshot channels/ports
-///
-/// This is the initial flavor of channels/ports used for comm module. This is
-/// an optimization for the one-use case of a channel. The major optimization of
-/// this type is to have one and exactly one allocation when the chan/port pair
-/// is created.
-///
-/// Another possible optimization would be to not use an Arc box because
-/// in theory we know when the shared packet can be deallocated (no real need
-/// for the atomic reference counting), but I was having trouble how to destroy
-/// the data early in a drop of a Port.
-///
-/// # Implementation
-///
-/// Oneshots are implemented around one atomic usize variable. This variable
-/// indicates both the state of the port/chan but also contains any threads
-/// blocked on the port. All atomic operations happen on this one word.
-///
-/// In order to upgrade a oneshot channel, an upgrade is considered a disconnect
-/// on behalf of the channel side of things (it can be mentally thought of as
-/// consuming the port). This upgrade is then also stored in the shared packet.
-/// The one caveat to consider is that when a port sees a disconnected channel
-/// it must check for data because there is no "data plus upgrade" state.
-pub use self::Failure::*;
-use self::MyUpgrade::*;
-pub use self::UpgradeResult::*;
-
-use crate::cell::UnsafeCell;
-use crate::ptr;
-use crate::sync::atomic::{AtomicPtr, Ordering};
-use crate::sync::mpsc::blocking::{self, SignalToken};
-use crate::sync::mpsc::Receiver;
-use crate::time::Instant;
-
-// Various states you can find a port in.
-const EMPTY: *mut u8 = ptr::invalid_mut::<u8>(0); // initial state: no data, no blocked receiver
-const DATA: *mut u8 = ptr::invalid_mut::<u8>(1); // data ready for receiver to take
-const DISCONNECTED: *mut u8 = ptr::invalid_mut::<u8>(2); // channel is disconnected OR upgraded
-// Any other value represents a pointer to a SignalToken value. The
-// protocol ensures that when the state moves *to* a pointer,
-// ownership of the token is given to the packet, and when the state
-// moves *from* a pointer, ownership of the token is transferred to
-// whoever changed the state.
-
-pub struct Packet<T> {
-    // Internal state of the chan/port pair (stores the blocked thread as well)
-    state: AtomicPtr<u8>,
-    // One-shot data slot location
-    data: UnsafeCell<Option<T>>,
-    // when used for the second time, a oneshot channel must be upgraded, and
-    // this contains the slot for the upgrade
-    upgrade: UnsafeCell<MyUpgrade<T>>,
-}
-
-pub enum Failure<T> {
-    Empty,
-    Disconnected,
-    Upgraded(Receiver<T>),
-}
-
-pub enum UpgradeResult {
-    UpSuccess,
-    UpDisconnected,
-    UpWoke(SignalToken),
-}
-
-enum MyUpgrade<T> {
-    NothingSent,
-    SendUsed,
-    GoUp(Receiver<T>),
-}
-
-impl<T> Packet<T> {
-    pub fn new() -> Packet<T> {
-        Packet {
-            data: UnsafeCell::new(None),
-            upgrade: UnsafeCell::new(NothingSent),
-            state: AtomicPtr::new(EMPTY),
-        }
-    }
-
-    pub fn send(&self, t: T) -> Result<(), T> {
-        unsafe {
-            // Sanity check
-            match *self.upgrade.get() {
-                NothingSent => {}
-                _ => panic!("sending on a oneshot that's already sent on "),
-            }
-            assert!((*self.data.get()).is_none());
-            ptr::write(self.data.get(), Some(t));
-            ptr::write(self.upgrade.get(), SendUsed);
-
-            match self.state.swap(DATA, Ordering::SeqCst) {
-                // Sent the data, no one was waiting
-                EMPTY => Ok(()),
-
-                // Couldn't send the data, the port hung up first. Return the data
-                // back up the stack.
-                DISCONNECTED => {
-                    self.state.swap(DISCONNECTED, Ordering::SeqCst);
-                    ptr::write(self.upgrade.get(), NothingSent);
-                    Err((&mut *self.data.get()).take().unwrap())
-                }
-
-                // Not possible, these are one-use channels
-                DATA => unreachable!(),
-
-                // There is a thread waiting on the other end. We leave the 'DATA'
-                // state inside so it'll pick it up on the other end.
-                ptr => {
-                    SignalToken::from_raw(ptr).signal();
-                    Ok(())
-                }
-            }
-        }
-    }
-
-    // Just tests whether this channel has been sent on or not, this is only
-    // safe to use from the sender.
-    pub fn sent(&self) -> bool {
-        unsafe { !matches!(*self.upgrade.get(), NothingSent) }
-    }
-
-    pub fn recv(&self, deadline: Option<Instant>) -> Result<T, Failure<T>> {
-        // Attempt to not block the thread (it's a little expensive). If it looks
-        // like we're not empty, then immediately go through to `try_recv`.
-        if self.state.load(Ordering::SeqCst) == EMPTY {
-            let (wait_token, signal_token) = blocking::tokens();
-            let ptr = unsafe { signal_token.to_raw() };
-
-            // race with senders to enter the blocking state
-            if self.state.compare_exchange(EMPTY, ptr, Ordering::SeqCst, Ordering::SeqCst).is_ok() {
-                if let Some(deadline) = deadline {
-                    let timed_out = !wait_token.wait_max_until(deadline);
-                    // Try to reset the state
-                    if timed_out {
-                        self.abort_selection().map_err(Upgraded)?;
-                    }
-                } else {
-                    wait_token.wait();
-                    debug_assert!(self.state.load(Ordering::SeqCst) != EMPTY);
-                }
-            } else {
-                // drop the signal token, since we never blocked
-                drop(unsafe { SignalToken::from_raw(ptr) });
-            }
-        }
-
-        self.try_recv()
-    }
-
-    pub fn try_recv(&self) -> Result<T, Failure<T>> {
-        unsafe {
-            match self.state.load(Ordering::SeqCst) {
-                EMPTY => Err(Empty),
-
-                // We saw some data on the channel, but the channel can be used
-                // again to send us an upgrade. As a result, we need to re-insert
-                // into the channel that there's no data available (otherwise we'll
-                // just see DATA next time). This is done as a cmpxchg because if
-                // the state changes under our feet we'd rather just see that state
-                // change.
-                DATA => {
-                    let _ = self.state.compare_exchange(
-                        DATA,
-                        EMPTY,
-                        Ordering::SeqCst,
-                        Ordering::SeqCst,
-                    );
-                    match (&mut *self.data.get()).take() {
-                        Some(data) => Ok(data),
-                        None => unreachable!(),
-                    }
-                }
-
-                // There's no guarantee that we receive before an upgrade happens,
-                // and an upgrade flags the channel as disconnected, so when we see
-                // this we first need to check if there's data available and *then*
-                // we go through and process the upgrade.
-                DISCONNECTED => match (&mut *self.data.get()).take() {
-                    Some(data) => Ok(data),
-                    None => match ptr::replace(self.upgrade.get(), SendUsed) {
-                        SendUsed | NothingSent => Err(Disconnected),
-                        GoUp(upgrade) => Err(Upgraded(upgrade)),
-                    },
-                },
-
-                // We are the sole receiver; there cannot be a blocking
-                // receiver already.
-                _ => unreachable!(),
-            }
-        }
-    }
-
-    // Returns whether the upgrade was completed. If the upgrade wasn't
-    // completed, then the port couldn't get sent to the other half (it will
-    // never receive it).
-    pub fn upgrade(&self, up: Receiver<T>) -> UpgradeResult {
-        unsafe {
-            let prev = match *self.upgrade.get() {
-                NothingSent => NothingSent,
-                SendUsed => SendUsed,
-                _ => panic!("upgrading again"),
-            };
-            ptr::write(self.upgrade.get(), GoUp(up));
-
-            match self.state.swap(DISCONNECTED, Ordering::SeqCst) {
-                // If the channel is empty or has data on it, then we're good to go.
-                // Senders will check the data before the upgrade (in case we
-                // plastered over the DATA state).
-                DATA | EMPTY => UpSuccess,
-
-                // If the other end is already disconnected, then we failed the
-                // upgrade. Be sure to trash the port we were given.
-                DISCONNECTED => {
-                    ptr::replace(self.upgrade.get(), prev);
-                    UpDisconnected
-                }
-
-                // If someone's waiting, we gotta wake them up
-                ptr => UpWoke(SignalToken::from_raw(ptr)),
-            }
-        }
-    }
-
-    pub fn drop_chan(&self) {
-        match self.state.swap(DISCONNECTED, Ordering::SeqCst) {
-            DATA | DISCONNECTED | EMPTY => {}
-
-            // If someone's waiting, we gotta wake them up
-            ptr => unsafe {
-                SignalToken::from_raw(ptr).signal();
-            },
-        }
-    }
-
-    pub fn drop_port(&self) {
-        match self.state.swap(DISCONNECTED, Ordering::SeqCst) {
-            // An empty channel has nothing to do, and a remotely disconnected
-            // channel also has nothing to do b/c we're about to run the drop
-            // glue
-            DISCONNECTED | EMPTY => {}
-
-            // There's data on the channel, so make sure we destroy it promptly.
-            // This is why not using an arc is a little difficult (need the box
-            // to stay valid while we take the data).
-            DATA => unsafe {
-                (&mut *self.data.get()).take().unwrap();
-            },
-
-            // We're the only ones that can block on this port
-            _ => unreachable!(),
-        }
-    }
-
-    ////////////////////////////////////////////////////////////////////////////
-    // select implementation
-    ////////////////////////////////////////////////////////////////////////////
-
-    // Remove a previous selecting thread from this port. This ensures that the
-    // blocked thread will no longer be visible to any other threads.
-    //
-    // The return value indicates whether there's data on this port.
-    pub fn abort_selection(&self) -> Result<bool, Receiver<T>> {
-        let state = match self.state.load(Ordering::SeqCst) {
-            // Each of these states means that no further activity will happen
-            // with regard to abortion selection
-            s @ (EMPTY | DATA | DISCONNECTED) => s,
-
-            // If we've got a blocked thread, then use an atomic to gain ownership
-            // of it (may fail)
-            ptr => self
-                .state
-                .compare_exchange(ptr, EMPTY, Ordering::SeqCst, Ordering::SeqCst)
-                .unwrap_or_else(|x| x),
-        };
-
-        // Now that we've got ownership of our state, figure out what to do
-        // about it.
-        match state {
-            EMPTY => unreachable!(),
-            // our thread used for select was stolen
-            DATA => Ok(true),
-
-            // If the other end has hung up, then we have complete ownership
-            // of the port. First, check if there was data waiting for us. This
-            // is possible if the other end sent something and then hung up.
-            //
-            // We then need to check to see if there was an upgrade requested,
-            // and if so, the upgraded port needs to have its selection aborted.
-            DISCONNECTED => unsafe {
-                if (*self.data.get()).is_some() {
-                    Ok(true)
-                } else {
-                    match ptr::replace(self.upgrade.get(), SendUsed) {
-                        GoUp(port) => Err(port),
-                        _ => Ok(true),
-                    }
-                }
-            },
-
-            // We woke ourselves up from select.
-            ptr => unsafe {
-                drop(SignalToken::from_raw(ptr));
-                Ok(false)
-            },
-        }
-    }
-}
-
-impl<T> Drop for Packet<T> {
-    fn drop(&mut self) {
-        assert_eq!(self.state.load(Ordering::SeqCst), DISCONNECTED);
-    }
-}
diff --git a/library/std/src/sync/mpsc/shared.rs b/library/std/src/sync/mpsc/shared.rs
deleted file mode 100644
index 51917bd96bd6..000000000000
--- a/library/std/src/sync/mpsc/shared.rs
+++ /dev/null
@@ -1,501 +0,0 @@
-/// Shared channels.
-///
-/// This is the flavor of channels which are not necessarily optimized for any
-/// particular use case, but are the most general in how they are used. Shared
-/// channels are cloneable allowing for multiple senders.
-///
-/// High level implementation details can be found in the comment of the parent
-/// module. You'll also note that the implementation of the shared and stream
-/// channels are quite similar, and this is no coincidence!
-pub use self::Failure::*;
-use self::StartResult::*;
-
-use core::cmp;
-use core::intrinsics::abort;
-
-use crate::cell::UnsafeCell;
-use crate::ptr;
-use crate::sync::atomic::{AtomicBool, AtomicIsize, AtomicPtr, AtomicUsize, Ordering};
-use crate::sync::mpsc::blocking::{self, SignalToken};
-use crate::sync::mpsc::mpsc_queue as mpsc;
-use crate::sync::{Mutex, MutexGuard};
-use crate::thread;
-use crate::time::Instant;
-
-const DISCONNECTED: isize = isize::MIN;
-const FUDGE: isize = 1024;
-const MAX_REFCOUNT: usize = (isize::MAX) as usize;
-#[cfg(test)]
-const MAX_STEALS: isize = 5;
-#[cfg(not(test))]
-const MAX_STEALS: isize = 1 << 20;
-const EMPTY: *mut u8 = ptr::null_mut(); // initial state: no data, no blocked receiver
-
-pub struct Packet<T> {
-    queue: mpsc::Queue<T>,
-    cnt: AtomicIsize,          // How many items are on this channel
-    steals: UnsafeCell<isize>, // How many times has a port received without blocking?
-    to_wake: AtomicPtr<u8>,    // SignalToken for wake up
-
-    // The number of channels which are currently using this packet.
-    channels: AtomicUsize,
-
-    // See the discussion in Port::drop and the channel send methods for what
-    // these are used for
-    port_dropped: AtomicBool,
-    sender_drain: AtomicIsize,
-
-    // this lock protects various portions of this implementation during
-    // select()
-    select_lock: Mutex<()>,
-}
-
-pub enum Failure {
-    Empty,
-    Disconnected,
-}
-
-#[derive(PartialEq, Eq)]
-enum StartResult {
-    Installed,
-    Abort,
-}
-
-impl<T> Packet<T> {
-    // Creation of a packet *must* be followed by a call to postinit_lock
-    // and later by inherit_blocker
-    pub fn new() -> Packet<T> {
-        Packet {
-            queue: mpsc::Queue::new(),
-            cnt: AtomicIsize::new(0),
-            steals: UnsafeCell::new(0),
-            to_wake: AtomicPtr::new(EMPTY),
-            channels: AtomicUsize::new(2),
-            port_dropped: AtomicBool::new(false),
-            sender_drain: AtomicIsize::new(0),
-            select_lock: Mutex::new(()),
-        }
-    }
-
-    // This function should be used after newly created Packet
-    // was wrapped with an Arc
-    // In other case mutex data will be duplicated while cloning
-    // and that could cause problems on platforms where it is
-    // represented by opaque data structure
-    pub fn postinit_lock(&self) -> MutexGuard<'_, ()> {
-        self.select_lock.lock().unwrap()
-    }
-
-    // This function is used at the creation of a shared packet to inherit a
-    // previously blocked thread. This is done to prevent spurious wakeups of
-    // threads in select().
-    //
-    // This can only be called at channel-creation time
-    pub fn inherit_blocker(&self, token: Option<SignalToken>, guard: MutexGuard<'_, ()>) {
-        if let Some(token) = token {
-            assert_eq!(self.cnt.load(Ordering::SeqCst), 0);
-            assert_eq!(self.to_wake.load(Ordering::SeqCst), EMPTY);
-            self.to_wake.store(unsafe { token.to_raw() }, Ordering::SeqCst);
-            self.cnt.store(-1, Ordering::SeqCst);
-
-            // This store is a little sketchy. What's happening here is that
-            // we're transferring a blocker from a oneshot or stream channel to
-            // this shared channel. In doing so, we never spuriously wake them
-            // up and rather only wake them up at the appropriate time. This
-            // implementation of shared channels assumes that any blocking
-            // recv() will undo the increment of steals performed in try_recv()
-            // once the recv is complete.  This thread that we're inheriting,
-            // however, is not in the middle of recv. Hence, the first time we
-            // wake them up, they're going to wake up from their old port, move
-            // on to the upgraded port, and then call the block recv() function.
-            //
-            // When calling this function, they'll find there's data immediately
-            // available, counting it as a steal. This in fact wasn't a steal
-            // because we appropriately blocked them waiting for data.
-            //
-            // To offset this bad increment, we initially set the steal count to
-            // -1. You'll find some special code in abort_selection() as well to
-            // ensure that this -1 steal count doesn't escape too far.
-            unsafe {
-                *self.steals.get() = -1;
-            }
-        }
-
-        // When the shared packet is constructed, we grabbed this lock. The
-        // purpose of this lock is to ensure that abort_selection() doesn't
-        // interfere with this method. After we unlock this lock, we're
-        // signifying that we're done modifying self.cnt and self.to_wake and
-        // the port is ready for the world to continue using it.
-        drop(guard);
-    }
-
-    pub fn send(&self, t: T) -> Result<(), T> {
-        // See Port::drop for what's going on
-        if self.port_dropped.load(Ordering::SeqCst) {
-            return Err(t);
-        }
-
-        // Note that the multiple sender case is a little trickier
-        // semantically than the single sender case. The logic for
-        // incrementing is "add and if disconnected store disconnected".
-        // This could end up leading some senders to believe that there
-        // wasn't a disconnect if in fact there was a disconnect. This means
-        // that while one thread is attempting to re-store the disconnected
-        // states, other threads could walk through merrily incrementing
-        // this very-negative disconnected count. To prevent senders from
-        // spuriously attempting to send when the channels is actually
-        // disconnected, the count has a ranged check here.
-        //
-        // This is also done for another reason. Remember that the return
-        // value of this function is:
-        //
-        //  `true` == the data *may* be received, this essentially has no
-        //            meaning
-        //  `false` == the data will *never* be received, this has a lot of
-        //             meaning
-        //
-        // In the SPSC case, we have a check of 'queue.is_empty()' to see
-        // whether the data was actually received, but this same condition
-        // means nothing in a multi-producer context. As a result, this
-        // preflight check serves as the definitive "this will never be
-        // received". Once we get beyond this check, we have permanently
-        // entered the realm of "this may be received"
-        if self.cnt.load(Ordering::SeqCst) < DISCONNECTED + FUDGE {
-            return Err(t);
-        }
-
-        self.queue.push(t);
-        match self.cnt.fetch_add(1, Ordering::SeqCst) {
-            -1 => {
-                self.take_to_wake().signal();
-            }
-
-            // In this case, we have possibly failed to send our data, and
-            // we need to consider re-popping the data in order to fully
-            // destroy it. We must arbitrate among the multiple senders,
-            // however, because the queues that we're using are
-            // single-consumer queues. In order to do this, all exiting
-            // pushers will use an atomic count in order to count those
-            // flowing through. Pushers who see 0 are required to drain as
-            // much as possible, and then can only exit when they are the
-            // only pusher (otherwise they must try again).
-            n if n < DISCONNECTED + FUDGE => {
-                // see the comment in 'try' for a shared channel for why this
-                // window of "not disconnected" is ok.
-                self.cnt.store(DISCONNECTED, Ordering::SeqCst);
-
-                if self.sender_drain.fetch_add(1, Ordering::SeqCst) == 0 {
-                    loop {
-                        // drain the queue, for info on the thread yield see the
-                        // discussion in try_recv
-                        loop {
-                            match self.queue.pop() {
-                                mpsc::Data(..) => {}
-                                mpsc::Empty => break,
-                                mpsc::Inconsistent => thread::yield_now(),
-                            }
-                        }
-                        // maybe we're done, if we're not the last ones
-                        // here, then we need to go try again.
-                        if self.sender_drain.fetch_sub(1, Ordering::SeqCst) == 1 {
-                            break;
-                        }
-                    }
-
-                    // At this point, there may still be data on the queue,
-                    // but only if the count hasn't been incremented and
-                    // some other sender hasn't finished pushing data just
-                    // yet. That sender in question will drain its own data.
-                }
-            }
-
-            // Can't make any assumptions about this case like in the SPSC case.
-            _ => {}
-        }
-
-        Ok(())
-    }
-
-    pub fn recv(&self, deadline: Option<Instant>) -> Result<T, Failure> {
-        // This code is essentially the exact same as that found in the stream
-        // case (see stream.rs)
-        match self.try_recv() {
-            Err(Empty) => {}
-            data => return data,
-        }
-
-        let (wait_token, signal_token) = blocking::tokens();
-        if self.decrement(signal_token) == Installed {
-            if let Some(deadline) = deadline {
-                let timed_out = !wait_token.wait_max_until(deadline);
-                if timed_out {
-                    self.abort_selection(false);
-                }
-            } else {
-                wait_token.wait();
-            }
-        }
-
-        match self.try_recv() {
-            data @ Ok(..) => unsafe {
-                *self.steals.get() -= 1;
-                data
-            },
-            data => data,
-        }
-    }
-
-    // Essentially the exact same thing as the stream decrement function.
-    // Returns true if blocking should proceed.
-    fn decrement(&self, token: SignalToken) -> StartResult {
-        unsafe {
-            assert_eq!(
-                self.to_wake.load(Ordering::SeqCst),
-                EMPTY,
-                "This is a known bug in the Rust standard library. See https://github.com/rust-lang/rust/issues/39364"
-            );
-            let ptr = token.to_raw();
-            self.to_wake.store(ptr, Ordering::SeqCst);
-
-            let steals = ptr::replace(self.steals.get(), 0);
-
-            match self.cnt.fetch_sub(1 + steals, Ordering::SeqCst) {
-                DISCONNECTED => {
-                    self.cnt.store(DISCONNECTED, Ordering::SeqCst);
-                }
-                // If we factor in our steals and notice that the channel has no
-                // data, we successfully sleep
-                n => {
-                    assert!(n >= 0);
-                    if n - steals <= 0 {
-                        return Installed;
-                    }
-                }
-            }
-
-            self.to_wake.store(EMPTY, Ordering::SeqCst);
-            drop(SignalToken::from_raw(ptr));
-            Abort
-        }
-    }
-
-    pub fn try_recv(&self) -> Result<T, Failure> {
-        let ret = match self.queue.pop() {
-            mpsc::Data(t) => Some(t),
-            mpsc::Empty => None,
-
-            // This is a bit of an interesting case. The channel is reported as
-            // having data available, but our pop() has failed due to the queue
-            // being in an inconsistent state.  This means that there is some
-            // pusher somewhere which has yet to complete, but we are guaranteed
-            // that a pop will eventually succeed. In this case, we spin in a
-            // yield loop because the remote sender should finish their enqueue
-            // operation "very quickly".
-            //
-            // Avoiding this yield loop would require a different queue
-            // abstraction which provides the guarantee that after M pushes have
-            // succeeded, at least M pops will succeed. The current queues
-            // guarantee that if there are N active pushes, you can pop N times
-            // once all N have finished.
-            mpsc::Inconsistent => {
-                let data;
-                loop {
-                    thread::yield_now();
-                    match self.queue.pop() {
-                        mpsc::Data(t) => {
-                            data = t;
-                            break;
-                        }
-                        mpsc::Empty => panic!("inconsistent => empty"),
-                        mpsc::Inconsistent => {}
-                    }
-                }
-                Some(data)
-            }
-        };
-        match ret {
-            // See the discussion in the stream implementation for why we
-            // might decrement steals.
-            Some(data) => unsafe {
-                if *self.steals.get() > MAX_STEALS {
-                    match self.cnt.swap(0, Ordering::SeqCst) {
-                        DISCONNECTED => {
-                            self.cnt.store(DISCONNECTED, Ordering::SeqCst);
-                        }
-                        n => {
-                            let m = cmp::min(n, *self.steals.get());
-                            *self.steals.get() -= m;
-                            self.bump(n - m);
-                        }
-                    }
-                    assert!(*self.steals.get() >= 0);
-                }
-                *self.steals.get() += 1;
-                Ok(data)
-            },
-
-            // See the discussion in the stream implementation for why we try
-            // again.
-            None => {
-                match self.cnt.load(Ordering::SeqCst) {
-                    n if n != DISCONNECTED => Err(Empty),
-                    _ => {
-                        match self.queue.pop() {
-                            mpsc::Data(t) => Ok(t),
-                            mpsc::Empty => Err(Disconnected),
-                            // with no senders, an inconsistency is impossible.
-                            mpsc::Inconsistent => unreachable!(),
-                        }
-                    }
-                }
-            }
-        }
-    }
-
-    // Prepares this shared packet for a channel clone, essentially just bumping
-    // a refcount.
-    pub fn clone_chan(&self) {
-        let old_count = self.channels.fetch_add(1, Ordering::SeqCst);
-
-        // See comments on Arc::clone() on why we do this (for `mem::forget`).
-        if old_count > MAX_REFCOUNT {
-            abort();
-        }
-    }
-
-    // Decrement the reference count on a channel. This is called whenever a
-    // Chan is dropped and may end up waking up a receiver. It's the receiver's
-    // responsibility on the other end to figure out that we've disconnected.
-    pub fn drop_chan(&self) {
-        match self.channels.fetch_sub(1, Ordering::SeqCst) {
-            1 => {}
-            n if n > 1 => return,
-            n => panic!("bad number of channels left {n}"),
-        }
-
-        match self.cnt.swap(DISCONNECTED, Ordering::SeqCst) {
-            -1 => {
-                self.take_to_wake().signal();
-            }
-            DISCONNECTED => {}
-            n => {
-                assert!(n >= 0);
-            }
-        }
-    }
-
-    // See the long discussion inside of stream.rs for why the queue is drained,
-    // and why it is done in this fashion.
-    pub fn drop_port(&self) {
-        self.port_dropped.store(true, Ordering::SeqCst);
-        let mut steals = unsafe { *self.steals.get() };
-        while {
-            match self.cnt.compare_exchange(
-                steals,
-                DISCONNECTED,
-                Ordering::SeqCst,
-                Ordering::SeqCst,
-            ) {
-                Ok(_) => false,
-                Err(old) => old != DISCONNECTED,
-            }
-        } {
-            // See the discussion in 'try_recv' for why we yield
-            // control of this thread.
-            loop {
-                match self.queue.pop() {
-                    mpsc::Data(..) => {
-                        steals += 1;
-                    }
-                    mpsc::Empty | mpsc::Inconsistent => break,
-                }
-            }
-        }
-    }
-
-    // Consumes ownership of the 'to_wake' field.
-    fn take_to_wake(&self) -> SignalToken {
-        let ptr = self.to_wake.load(Ordering::SeqCst);
-        self.to_wake.store(EMPTY, Ordering::SeqCst);
-        assert!(ptr != EMPTY);
-        unsafe { SignalToken::from_raw(ptr) }
-    }
-
-    ////////////////////////////////////////////////////////////////////////////
-    // select implementation
-    ////////////////////////////////////////////////////////////////////////////
-
-    // increment the count on the channel (used for selection)
-    fn bump(&self, amt: isize) -> isize {
-        match self.cnt.fetch_add(amt, Ordering::SeqCst) {
-            DISCONNECTED => {
-                self.cnt.store(DISCONNECTED, Ordering::SeqCst);
-                DISCONNECTED
-            }
-            n => n,
-        }
-    }
-
-    // Cancels a previous thread waiting on this port, returning whether there's
-    // data on the port.
-    //
-    // This is similar to the stream implementation (hence fewer comments), but
-    // uses a different value for the "steals" variable.
-    pub fn abort_selection(&self, _was_upgrade: bool) -> bool {
-        // Before we do anything else, we bounce on this lock. The reason for
-        // doing this is to ensure that any upgrade-in-progress is gone and
-        // done with. Without this bounce, we can race with inherit_blocker
-        // about looking at and dealing with to_wake. Once we have acquired the
-        // lock, we are guaranteed that inherit_blocker is done.
-        {
-            let _guard = self.select_lock.lock().unwrap();
-        }
-
-        // Like the stream implementation, we want to make sure that the count
-        // on the channel goes non-negative. We don't know how negative the
-        // stream currently is, so instead of using a steal value of 1, we load
-        // the channel count and figure out what we should do to make it
-        // positive.
-        let steals = {
-            let cnt = self.cnt.load(Ordering::SeqCst);
-            if cnt < 0 && cnt != DISCONNECTED { -cnt } else { 0 }
-        };
-        let prev = self.bump(steals + 1);
-
-        if prev == DISCONNECTED {
-            assert_eq!(self.to_wake.load(Ordering::SeqCst), EMPTY);
-            true
-        } else {
-            let cur = prev + steals + 1;
-            assert!(cur >= 0);
-            if prev < 0 {
-                drop(self.take_to_wake());
-            } else {
-                while self.to_wake.load(Ordering::SeqCst) != EMPTY {
-                    thread::yield_now();
-                }
-            }
-            unsafe {
-                // if the number of steals is -1, it was the pre-emptive -1 steal
-                // count from when we inherited a blocker. This is fine because
-                // we're just going to overwrite it with a real value.
-                let old = self.steals.get();
-                assert!(*old == 0 || *old == -1);
-                *old = steals;
-                prev >= 0
-            }
-        }
-    }
-}
-
-impl<T> Drop for Packet<T> {
-    fn drop(&mut self) {
-        // Note that this load is not only an assert for correctness about
-        // disconnection, but also a proper fence before the read of
-        // `to_wake`, so this assert cannot be removed with also removing
-        // the `to_wake` assert.
-        assert_eq!(self.cnt.load(Ordering::SeqCst), DISCONNECTED);
-        assert_eq!(self.to_wake.load(Ordering::SeqCst), EMPTY);
-        assert_eq!(self.channels.load(Ordering::SeqCst), 0);
-    }
-}
diff --git a/library/std/src/sync/mpsc/spsc_queue.rs b/library/std/src/sync/mpsc/spsc_queue.rs
deleted file mode 100644
index 7e745eb31de6..000000000000
--- a/library/std/src/sync/mpsc/spsc_queue.rs
+++ /dev/null
@@ -1,236 +0,0 @@
-//! A single-producer single-consumer concurrent queue
-//!
-//! This module contains the implementation of an SPSC queue which can be used
-//! concurrently between two threads. This data structure is safe to use and
-//! enforces the semantics that there is one pusher and one popper.
-
-// https://www.1024cores.net/home/lock-free-algorithms/queues/unbounded-spsc-queue
-
-#[cfg(all(test, not(target_os = "emscripten")))]
-mod tests;
-
-use core::cell::UnsafeCell;
-use core::ptr;
-
-use crate::boxed::Box;
-use crate::sync::atomic::{AtomicPtr, AtomicUsize, Ordering};
-
-use super::cache_aligned::CacheAligned;
-
-// Node within the linked list queue of messages to send
-struct Node<T> {
-    // FIXME: this could be an uninitialized T if we're careful enough, and
-    //      that would reduce memory usage (and be a bit faster).
-    //      is it worth it?
-    value: Option<T>,         // nullable for re-use of nodes
-    cached: bool,             // This node goes into the node cache
-    next: AtomicPtr<Node<T>>, // next node in the queue
-}
-
-/// The single-producer single-consumer queue. This structure is not cloneable,
-/// but it can be safely shared in an Arc if it is guaranteed that there
-/// is only one popper and one pusher touching the queue at any one point in
-/// time.
-pub struct Queue<T, ProducerAddition = (), ConsumerAddition = ()> {
-    // consumer fields
-    consumer: CacheAligned<Consumer<T, ConsumerAddition>>,
-
-    // producer fields
-    producer: CacheAligned<Producer<T, ProducerAddition>>,
-}
-
-struct Consumer<T, Addition> {
-    tail: UnsafeCell<*mut Node<T>>, // where to pop from
-    tail_prev: AtomicPtr<Node<T>>,  // where to pop from
-    cache_bound: usize,             // maximum cache size
-    cached_nodes: AtomicUsize,      // number of nodes marked as cacheable
-    addition: Addition,
-}
-
-struct Producer<T, Addition> {
-    head: UnsafeCell<*mut Node<T>>,      // where to push to
-    first: UnsafeCell<*mut Node<T>>,     // where to get new nodes from
-    tail_copy: UnsafeCell<*mut Node<T>>, // between first/tail
-    addition: Addition,
-}
-
-unsafe impl<T: Send, P: Send + Sync, C: Send + Sync> Send for Queue<T, P, C> {}
-
-unsafe impl<T: Send, P: Send + Sync, C: Send + Sync> Sync for Queue<T, P, C> {}
-
-impl<T> Node<T> {
-    fn new() -> *mut Node<T> {
-        Box::into_raw(box Node {
-            value: None,
-            cached: false,
-            next: AtomicPtr::new(ptr::null_mut::<Node<T>>()),
-        })
-    }
-}
-
-impl<T, ProducerAddition, ConsumerAddition> Queue<T, ProducerAddition, ConsumerAddition> {
-    /// Creates a new queue. With given additional elements in the producer and
-    /// consumer portions of the queue.
-    ///
-    /// Due to the performance implications of cache-contention,
-    /// we wish to keep fields used mainly by the producer on a separate cache
-    /// line than those used by the consumer.
-    /// Since cache lines are usually 64 bytes, it is unreasonably expensive to
-    /// allocate one for small fields, so we allow users to insert additional
-    /// fields into the cache lines already allocated by this for the producer
-    /// and consumer.
-    ///
-    /// This is unsafe as the type system doesn't enforce a single
-    /// consumer-producer relationship. It also allows the consumer to `pop`
-    /// items while there is a `peek` active due to all methods having a
-    /// non-mutable receiver.
-    ///
-    /// # Arguments
-    ///
-    ///   * `bound` - This queue implementation is implemented with a linked
-    ///               list, and this means that a push is always a malloc. In
-    ///               order to amortize this cost, an internal cache of nodes is
-    ///               maintained to prevent a malloc from always being
-    ///               necessary. This bound is the limit on the size of the
-    ///               cache (if desired). If the value is 0, then the cache has
-    ///               no bound. Otherwise, the cache will never grow larger than
-    ///               `bound` (although the queue itself could be much larger.
-    pub unsafe fn with_additions(
-        bound: usize,
-        producer_addition: ProducerAddition,
-        consumer_addition: ConsumerAddition,
-    ) -> Self {
-        let n1 = Node::new();
-        let n2 = Node::new();
-        (*n1).next.store(n2, Ordering::Relaxed);
-        Queue {
-            consumer: CacheAligned::new(Consumer {
-                tail: UnsafeCell::new(n2),
-                tail_prev: AtomicPtr::new(n1),
-                cache_bound: bound,
-                cached_nodes: AtomicUsize::new(0),
-                addition: consumer_addition,
-            }),
-            producer: CacheAligned::new(Producer {
-                head: UnsafeCell::new(n2),
-                first: UnsafeCell::new(n1),
-                tail_copy: UnsafeCell::new(n1),
-                addition: producer_addition,
-            }),
-        }
-    }
-
-    /// Pushes a new value onto this queue. Note that to use this function
-    /// safely, it must be externally guaranteed that there is only one pusher.
-    pub fn push(&self, t: T) {
-        unsafe {
-            // Acquire a node (which either uses a cached one or allocates a new
-            // one), and then append this to the 'head' node.
-            let n = self.alloc();
-            assert!((*n).value.is_none());
-            (*n).value = Some(t);
-            (*n).next.store(ptr::null_mut(), Ordering::Relaxed);
-            (**self.producer.head.get()).next.store(n, Ordering::Release);
-            *(&self.producer.head).get() = n;
-        }
-    }
-
-    unsafe fn alloc(&self) -> *mut Node<T> {
-        // First try to see if we can consume the 'first' node for our uses.
-        if *self.producer.first.get() != *self.producer.tail_copy.get() {
-            let ret = *self.producer.first.get();
-            *self.producer.0.first.get() = (*ret).next.load(Ordering::Relaxed);
-            return ret;
-        }
-        // If the above fails, then update our copy of the tail and try
-        // again.
-        *self.producer.0.tail_copy.get() = self.consumer.tail_prev.load(Ordering::Acquire);
-        if *self.producer.first.get() != *self.producer.tail_copy.get() {
-            let ret = *self.producer.first.get();
-            *self.producer.0.first.get() = (*ret).next.load(Ordering::Relaxed);
-            return ret;
-        }
-        // If all of that fails, then we have to allocate a new node
-        // (there's nothing in the node cache).
-        Node::new()
-    }
-
-    /// Attempts to pop a value from this queue. Remember that to use this type
-    /// safely you must ensure that there is only one popper at a time.
-    pub fn pop(&self) -> Option<T> {
-        unsafe {
-            // The `tail` node is not actually a used node, but rather a
-            // sentinel from where we should start popping from. Hence, look at
-            // tail's next field and see if we can use it. If we do a pop, then
-            // the current tail node is a candidate for going into the cache.
-            let tail = *self.consumer.tail.get();
-            let next = (*tail).next.load(Ordering::Acquire);
-            if next.is_null() {
-                return None;
-            }
-            assert!((*next).value.is_some());
-            let ret = (*next).value.take();
-
-            *self.consumer.0.tail.get() = next;
-            if self.consumer.cache_bound == 0 {
-                self.consumer.tail_prev.store(tail, Ordering::Release);
-            } else {
-                let cached_nodes = self.consumer.cached_nodes.load(Ordering::Relaxed);
-                if cached_nodes < self.consumer.cache_bound && !(*tail).cached {
-                    self.consumer.cached_nodes.store(cached_nodes, Ordering::Relaxed);
-                    (*tail).cached = true;
-                }
-
-                if (*tail).cached {
-                    self.consumer.tail_prev.store(tail, Ordering::Release);
-                } else {
-                    (*self.consumer.tail_prev.load(Ordering::Relaxed))
-                        .next
-                        .store(next, Ordering::Relaxed);
-                    // We have successfully erased all references to 'tail', so
-                    // now we can safely drop it.
-                    let _: Box<Node<T>> = Box::from_raw(tail);
-                }
-            }
-            ret
-        }
-    }
-
-    /// Attempts to peek at the head of the queue, returning `None` if the queue
-    /// has no data currently
-    ///
-    /// # Warning
-    /// The reference returned is invalid if it is not used before the consumer
-    /// pops the value off the queue. If the producer then pushes another value
-    /// onto the queue, it will overwrite the value pointed to by the reference.
-    pub fn peek(&self) -> Option<&mut T> {
-        // This is essentially the same as above with all the popping bits
-        // stripped out.
-        unsafe {
-            let tail = *self.consumer.tail.get();
-            let next = (*tail).next.load(Ordering::Acquire);
-            if next.is_null() { None } else { (*next).value.as_mut() }
-        }
-    }
-
-    pub fn producer_addition(&self) -> &ProducerAddition {
-        &self.producer.addition
-    }
-
-    pub fn consumer_addition(&self) -> &ConsumerAddition {
-        &self.consumer.addition
-    }
-}
-
-impl<T, ProducerAddition, ConsumerAddition> Drop for Queue<T, ProducerAddition, ConsumerAddition> {
-    fn drop(&mut self) {
-        unsafe {
-            let mut cur = *self.producer.first.get();
-            while !cur.is_null() {
-                let next = (*cur).next.load(Ordering::Relaxed);
-                let _n: Box<Node<T>> = Box::from_raw(cur);
-                cur = next;
-            }
-        }
-    }
-}
diff --git a/library/std/src/sync/mpsc/spsc_queue/tests.rs b/library/std/src/sync/mpsc/spsc_queue/tests.rs
deleted file mode 100644
index eb6d5c2cf66d..000000000000
--- a/library/std/src/sync/mpsc/spsc_queue/tests.rs
+++ /dev/null
@@ -1,102 +0,0 @@
-use super::Queue;
-use crate::sync::mpsc::channel;
-use crate::sync::Arc;
-use crate::thread;
-
-#[test]
-fn smoke() {
-    unsafe {
-        let queue = Queue::with_additions(0, (), ());
-        queue.push(1);
-        queue.push(2);
-        assert_eq!(queue.pop(), Some(1));
-        assert_eq!(queue.pop(), Some(2));
-        assert_eq!(queue.pop(), None);
-        queue.push(3);
-        queue.push(4);
-        assert_eq!(queue.pop(), Some(3));
-        assert_eq!(queue.pop(), Some(4));
-        assert_eq!(queue.pop(), None);
-    }
-}
-
-#[test]
-fn peek() {
-    unsafe {
-        let queue = Queue::with_additions(0, (), ());
-        queue.push(vec![1]);
-
-        // Ensure the borrowchecker works
-        match queue.peek() {
-            Some(vec) => {
-                assert_eq!(&*vec, &[1]);
-            }
-            None => unreachable!(),
-        }
-
-        match queue.pop() {
-            Some(vec) => {
-                assert_eq!(&*vec, &[1]);
-            }
-            None => unreachable!(),
-        }
-    }
-}
-
-#[test]
-fn drop_full() {
-    unsafe {
-        let q: Queue<Box<_>> = Queue::with_additions(0, (), ());
-        q.push(Box::new(1));
-        q.push(Box::new(2));
-    }
-}
-
-#[test]
-fn smoke_bound() {
-    unsafe {
-        let q = Queue::with_additions(0, (), ());
-        q.push(1);
-        q.push(2);
-        assert_eq!(q.pop(), Some(1));
-        assert_eq!(q.pop(), Some(2));
-        assert_eq!(q.pop(), None);
-        q.push(3);
-        q.push(4);
-        assert_eq!(q.pop(), Some(3));
-        assert_eq!(q.pop(), Some(4));
-        assert_eq!(q.pop(), None);
-    }
-}
-
-#[test]
-fn stress() {
-    unsafe {
-        stress_bound(0);
-        stress_bound(1);
-    }
-
-    unsafe fn stress_bound(bound: usize) {
-        let count = if cfg!(miri) { 1000 } else { 100000 };
-        let q = Arc::new(Queue::with_additions(bound, (), ()));
-
-        let (tx, rx) = channel();
-        let q2 = q.clone();
-        let _t = thread::spawn(move || {
-            for _ in 0..count {
-                loop {
-                    match q2.pop() {
-                        Some(1) => break,
-                        Some(_) => panic!(),
-                        None => {}
-                    }
-                }
-            }
-            tx.send(()).unwrap();
-        });
-        for _ in 0..count {
-            q.push(1);
-        }
-        rx.recv().unwrap();
-    }
-}
diff --git a/library/std/src/sync/mpsc/stream.rs b/library/std/src/sync/mpsc/stream.rs
deleted file mode 100644
index 4c3812c79f61..000000000000
--- a/library/std/src/sync/mpsc/stream.rs
+++ /dev/null
@@ -1,457 +0,0 @@
-/// Stream channels
-///
-/// This is the flavor of channels which are optimized for one sender and one
-/// receiver. The sender will be upgraded to a shared channel if the channel is
-/// cloned.
-///
-/// High level implementation details can be found in the comment of the parent
-/// module.
-pub use self::Failure::*;
-use self::Message::*;
-pub use self::UpgradeResult::*;
-
-use core::cmp;
-
-use crate::cell::UnsafeCell;
-use crate::ptr;
-use crate::thread;
-use crate::time::Instant;
-
-use crate::sync::atomic::{AtomicBool, AtomicIsize, AtomicPtr, Ordering};
-use crate::sync::mpsc::blocking::{self, SignalToken};
-use crate::sync::mpsc::spsc_queue as spsc;
-use crate::sync::mpsc::Receiver;
-
-const DISCONNECTED: isize = isize::MIN;
-#[cfg(test)]
-const MAX_STEALS: isize = 5;
-#[cfg(not(test))]
-const MAX_STEALS: isize = 1 << 20;
-const EMPTY: *mut u8 = ptr::null_mut(); // initial state: no data, no blocked receiver
-
-pub struct Packet<T> {
-    // internal queue for all messages
-    queue: spsc::Queue<Message<T>, ProducerAddition, ConsumerAddition>,
-}
-
-struct ProducerAddition {
-    cnt: AtomicIsize,       // How many items are on this channel
-    to_wake: AtomicPtr<u8>, // SignalToken for the blocked thread to wake up
-
-    port_dropped: AtomicBool, // flag if the channel has been destroyed.
-}
-
-struct ConsumerAddition {
-    steals: UnsafeCell<isize>, // How many times has a port received without blocking?
-}
-
-pub enum Failure<T> {
-    Empty,
-    Disconnected,
-    Upgraded(Receiver<T>),
-}
-
-pub enum UpgradeResult {
-    UpSuccess,
-    UpDisconnected,
-    UpWoke(SignalToken),
-}
-
-// Any message could contain an "upgrade request" to a new shared port, so the
-// internal queue it's a queue of T, but rather Message<T>
-enum Message<T> {
-    Data(T),
-    GoUp(Receiver<T>),
-}
-
-impl<T> Packet<T> {
-    pub fn new() -> Packet<T> {
-        Packet {
-            queue: unsafe {
-                spsc::Queue::with_additions(
-                    128,
-                    ProducerAddition {
-                        cnt: AtomicIsize::new(0),
-                        to_wake: AtomicPtr::new(EMPTY),
-
-                        port_dropped: AtomicBool::new(false),
-                    },
-                    ConsumerAddition { steals: UnsafeCell::new(0) },
-                )
-            },
-        }
-    }
-
-    pub fn send(&self, t: T) -> Result<(), T> {
-        // If the other port has deterministically gone away, then definitely
-        // must return the data back up the stack. Otherwise, the data is
-        // considered as being sent.
-        if self.queue.producer_addition().port_dropped.load(Ordering::SeqCst) {
-            return Err(t);
-        }
-
-        match self.do_send(Data(t)) {
-            UpSuccess | UpDisconnected => {}
-            UpWoke(token) => {
-                token.signal();
-            }
-        }
-        Ok(())
-    }
-
-    pub fn upgrade(&self, up: Receiver<T>) -> UpgradeResult {
-        // If the port has gone away, then there's no need to proceed any
-        // further.
-        if self.queue.producer_addition().port_dropped.load(Ordering::SeqCst) {
-            return UpDisconnected;
-        }
-
-        self.do_send(GoUp(up))
-    }
-
-    fn do_send(&self, t: Message<T>) -> UpgradeResult {
-        self.queue.push(t);
-        match self.queue.producer_addition().cnt.fetch_add(1, Ordering::SeqCst) {
-            // As described in the mod's doc comment, -1 == wakeup
-            -1 => UpWoke(self.take_to_wake()),
-            // As as described before, SPSC queues must be >= -2
-            -2 => UpSuccess,
-
-            // Be sure to preserve the disconnected state, and the return value
-            // in this case is going to be whether our data was received or not.
-            // This manifests itself on whether we have an empty queue or not.
-            //
-            // Primarily, are required to drain the queue here because the port
-            // will never remove this data. We can only have at most one item to
-            // drain (the port drains the rest).
-            DISCONNECTED => {
-                self.queue.producer_addition().cnt.store(DISCONNECTED, Ordering::SeqCst);
-                let first = self.queue.pop();
-                let second = self.queue.pop();
-                assert!(second.is_none());
-
-                match first {
-                    Some(..) => UpSuccess,  // we failed to send the data
-                    None => UpDisconnected, // we successfully sent data
-                }
-            }
-
-            // Otherwise we just sent some data on a non-waiting queue, so just
-            // make sure the world is sane and carry on!
-            n => {
-                assert!(n >= 0);
-                UpSuccess
-            }
-        }
-    }
-
-    // Consumes ownership of the 'to_wake' field.
-    fn take_to_wake(&self) -> SignalToken {
-        let ptr = self.queue.producer_addition().to_wake.load(Ordering::SeqCst);
-        self.queue.producer_addition().to_wake.store(EMPTY, Ordering::SeqCst);
-        assert!(ptr != EMPTY);
-        unsafe { SignalToken::from_raw(ptr) }
-    }
-
-    // Decrements the count on the channel for a sleeper, returning the sleeper
-    // back if it shouldn't sleep. Note that this is the location where we take
-    // steals into account.
-    fn decrement(&self, token: SignalToken) -> Result<(), SignalToken> {
-        assert_eq!(self.queue.producer_addition().to_wake.load(Ordering::SeqCst), EMPTY);
-        let ptr = unsafe { token.to_raw() };
-        self.queue.producer_addition().to_wake.store(ptr, Ordering::SeqCst);
-
-        let steals = unsafe { ptr::replace(self.queue.consumer_addition().steals.get(), 0) };
-
-        match self.queue.producer_addition().cnt.fetch_sub(1 + steals, Ordering::SeqCst) {
-            DISCONNECTED => {
-                self.queue.producer_addition().cnt.store(DISCONNECTED, Ordering::SeqCst);
-            }
-            // If we factor in our steals and notice that the channel has no
-            // data, we successfully sleep
-            n => {
-                assert!(n >= 0);
-                if n - steals <= 0 {
-                    return Ok(());
-                }
-            }
-        }
-
-        self.queue.producer_addition().to_wake.store(EMPTY, Ordering::SeqCst);
-        Err(unsafe { SignalToken::from_raw(ptr) })
-    }
-
-    pub fn recv(&self, deadline: Option<Instant>) -> Result<T, Failure<T>> {
-        // Optimistic preflight check (scheduling is expensive).
-        match self.try_recv() {
-            Err(Empty) => {}
-            data => return data,
-        }
-
-        // Welp, our channel has no data. Deschedule the current thread and
-        // initiate the blocking protocol.
-        let (wait_token, signal_token) = blocking::tokens();
-        if self.decrement(signal_token).is_ok() {
-            if let Some(deadline) = deadline {
-                let timed_out = !wait_token.wait_max_until(deadline);
-                if timed_out {
-                    self.abort_selection(/* was_upgrade = */ false).map_err(Upgraded)?;
-                }
-            } else {
-                wait_token.wait();
-            }
-        }
-
-        match self.try_recv() {
-            // Messages which actually popped from the queue shouldn't count as
-            // a steal, so offset the decrement here (we already have our
-            // "steal" factored into the channel count above).
-            data @ (Ok(..) | Err(Upgraded(..))) => unsafe {
-                *self.queue.consumer_addition().steals.get() -= 1;
-                data
-            },
-
-            data => data,
-        }
-    }
-
-    pub fn try_recv(&self) -> Result<T, Failure<T>> {
-        match self.queue.pop() {
-            // If we stole some data, record to that effect (this will be
-            // factored into cnt later on).
-            //
-            // Note that we don't allow steals to grow without bound in order to
-            // prevent eventual overflow of either steals or cnt as an overflow
-            // would have catastrophic results. Sometimes, steals > cnt, but
-            // other times cnt > steals, so we don't know the relation between
-            // steals and cnt. This code path is executed only rarely, so we do
-            // a pretty slow operation, of swapping 0 into cnt, taking steals
-            // down as much as possible (without going negative), and then
-            // adding back in whatever we couldn't factor into steals.
-            Some(data) => unsafe {
-                if *self.queue.consumer_addition().steals.get() > MAX_STEALS {
-                    match self.queue.producer_addition().cnt.swap(0, Ordering::SeqCst) {
-                        DISCONNECTED => {
-                            self.queue
-                                .producer_addition()
-                                .cnt
-                                .store(DISCONNECTED, Ordering::SeqCst);
-                        }
-                        n => {
-                            let m = cmp::min(n, *self.queue.consumer_addition().steals.get());
-                            *self.queue.consumer_addition().steals.get() -= m;
-                            self.bump(n - m);
-                        }
-                    }
-                    assert!(*self.queue.consumer_addition().steals.get() >= 0);
-                }
-                *self.queue.consumer_addition().steals.get() += 1;
-                match data {
-                    Data(t) => Ok(t),
-                    GoUp(up) => Err(Upgraded(up)),
-                }
-            },
-
-            None => {
-                match self.queue.producer_addition().cnt.load(Ordering::SeqCst) {
-                    n if n != DISCONNECTED => Err(Empty),
-
-                    // This is a little bit of a tricky case. We failed to pop
-                    // data above, and then we have viewed that the channel is
-                    // disconnected. In this window more data could have been
-                    // sent on the channel. It doesn't really make sense to
-                    // return that the channel is disconnected when there's
-                    // actually data on it, so be extra sure there's no data by
-                    // popping one more time.
-                    //
-                    // We can ignore steals because the other end is
-                    // disconnected and we'll never need to really factor in our
-                    // steals again.
-                    _ => match self.queue.pop() {
-                        Some(Data(t)) => Ok(t),
-                        Some(GoUp(up)) => Err(Upgraded(up)),
-                        None => Err(Disconnected),
-                    },
-                }
-            }
-        }
-    }
-
-    pub fn drop_chan(&self) {
-        // Dropping a channel is pretty simple, we just flag it as disconnected
-        // and then wakeup a blocker if there is one.
-        match self.queue.producer_addition().cnt.swap(DISCONNECTED, Ordering::SeqCst) {
-            -1 => {
-                self.take_to_wake().signal();
-            }
-            DISCONNECTED => {}
-            n => {
-                assert!(n >= 0);
-            }
-        }
-    }
-
-    pub fn drop_port(&self) {
-        // Dropping a port seems like a fairly trivial thing. In theory all we
-        // need to do is flag that we're disconnected and then everything else
-        // can take over (we don't have anyone to wake up).
-        //
-        // The catch for Ports is that we want to drop the entire contents of
-        // the queue. There are multiple reasons for having this property, the
-        // largest of which is that if another chan is waiting in this channel
-        // (but not received yet), then waiting on that port will cause a
-        // deadlock.
-        //
-        // So if we accept that we must now destroy the entire contents of the
-        // queue, this code may make a bit more sense. The tricky part is that
-        // we can't let any in-flight sends go un-dropped, we have to make sure
-        // *everything* is dropped and nothing new will come onto the channel.
-
-        // The first thing we do is set a flag saying that we're done for. All
-        // sends are gated on this flag, so we're immediately guaranteed that
-        // there are a bounded number of active sends that we'll have to deal
-        // with.
-        self.queue.producer_addition().port_dropped.store(true, Ordering::SeqCst);
-
-        // Now that we're guaranteed to deal with a bounded number of senders,
-        // we need to drain the queue. This draining process happens atomically
-        // with respect to the "count" of the channel. If the count is nonzero
-        // (with steals taken into account), then there must be data on the
-        // channel. In this case we drain everything and then try again. We will
-        // continue to fail while active senders send data while we're dropping
-        // data, but eventually we're guaranteed to break out of this loop
-        // (because there is a bounded number of senders).
-        let mut steals = unsafe { *self.queue.consumer_addition().steals.get() };
-        while {
-            match self.queue.producer_addition().cnt.compare_exchange(
-                steals,
-                DISCONNECTED,
-                Ordering::SeqCst,
-                Ordering::SeqCst,
-            ) {
-                Ok(_) => false,
-                Err(old) => old != DISCONNECTED,
-            }
-        } {
-            while self.queue.pop().is_some() {
-                steals += 1;
-            }
-        }
-
-        // At this point in time, we have gated all future senders from sending,
-        // and we have flagged the channel as being disconnected. The senders
-        // still have some responsibility, however, because some sends might not
-        // complete until after we flag the disconnection. There are more
-        // details in the sending methods that see DISCONNECTED
-    }
-
-    ////////////////////////////////////////////////////////////////////////////
-    // select implementation
-    ////////////////////////////////////////////////////////////////////////////
-
-    // increment the count on the channel (used for selection)
-    fn bump(&self, amt: isize) -> isize {
-        match self.queue.producer_addition().cnt.fetch_add(amt, Ordering::SeqCst) {
-            DISCONNECTED => {
-                self.queue.producer_addition().cnt.store(DISCONNECTED, Ordering::SeqCst);
-                DISCONNECTED
-            }
-            n => n,
-        }
-    }
-
-    // Removes a previous thread from being blocked in this port
-    pub fn abort_selection(&self, was_upgrade: bool) -> Result<bool, Receiver<T>> {
-        // If we're aborting selection after upgrading from a oneshot, then
-        // we're guarantee that no one is waiting. The only way that we could
-        // have seen the upgrade is if data was actually sent on the channel
-        // half again. For us, this means that there is guaranteed to be data on
-        // this channel. Furthermore, we're guaranteed that there was no
-        // start_selection previously, so there's no need to modify `self.cnt`
-        // at all.
-        //
-        // Hence, because of these invariants, we immediately return `Ok(true)`.
-        // Note that the data might not actually be sent on the channel just yet.
-        // The other end could have flagged the upgrade but not sent data to
-        // this end. This is fine because we know it's a small bounded windows
-        // of time until the data is actually sent.
-        if was_upgrade {
-            assert_eq!(unsafe { *self.queue.consumer_addition().steals.get() }, 0);
-            assert_eq!(self.queue.producer_addition().to_wake.load(Ordering::SeqCst), EMPTY);
-            return Ok(true);
-        }
-
-        // We want to make sure that the count on the channel goes non-negative,
-        // and in the stream case we can have at most one steal, so just assume
-        // that we had one steal.
-        let steals = 1;
-        let prev = self.bump(steals + 1);
-
-        // If we were previously disconnected, then we know for sure that there
-        // is no thread in to_wake, so just keep going
-        let has_data = if prev == DISCONNECTED {
-            assert_eq!(self.queue.producer_addition().to_wake.load(Ordering::SeqCst), EMPTY);
-            true // there is data, that data is that we're disconnected
-        } else {
-            let cur = prev + steals + 1;
-            assert!(cur >= 0);
-
-            // If the previous count was negative, then we just made things go
-            // positive, hence we passed the -1 boundary and we're responsible
-            // for removing the to_wake() field and trashing it.
-            //
-            // If the previous count was positive then we're in a tougher
-            // situation. A possible race is that a sender just incremented
-            // through -1 (meaning it's going to try to wake a thread up), but it
-            // hasn't yet read the to_wake. In order to prevent a future recv()
-            // from waking up too early (this sender picking up the plastered
-            // over to_wake), we spin loop here waiting for to_wake to be 0.
-            // Note that this entire select() implementation needs an overhaul,
-            // and this is *not* the worst part of it, so this is not done as a
-            // final solution but rather out of necessity for now to get
-            // something working.
-            if prev < 0 {
-                drop(self.take_to_wake());
-            } else {
-                while self.queue.producer_addition().to_wake.load(Ordering::SeqCst) != EMPTY {
-                    thread::yield_now();
-                }
-            }
-            unsafe {
-                assert_eq!(*self.queue.consumer_addition().steals.get(), 0);
-                *self.queue.consumer_addition().steals.get() = steals;
-            }
-
-            // if we were previously positive, then there's surely data to
-            // receive
-            prev >= 0
-        };
-
-        // Now that we've determined that this queue "has data", we peek at the
-        // queue to see if the data is an upgrade or not. If it's an upgrade,
-        // then we need to destroy this port and abort selection on the
-        // upgraded port.
-        if has_data {
-            match self.queue.peek() {
-                Some(&mut GoUp(..)) => match self.queue.pop() {
-                    Some(GoUp(port)) => Err(port),
-                    _ => unreachable!(),
-                },
-                _ => Ok(true),
-            }
-        } else {
-            Ok(false)
-        }
-    }
-}
-
-impl<T> Drop for Packet<T> {
-    fn drop(&mut self) {
-        // Note that this load is not only an assert for correctness about
-        // disconnection, but also a proper fence before the read of
-        // `to_wake`, so this assert cannot be removed with also removing
-        // the `to_wake` assert.
-        assert_eq!(self.queue.producer_addition().cnt.load(Ordering::SeqCst), DISCONNECTED);
-        assert_eq!(self.queue.producer_addition().to_wake.load(Ordering::SeqCst), EMPTY);
-    }
-}
diff --git a/library/std/src/sync/mpsc/sync.rs b/library/std/src/sync/mpsc/sync.rs
deleted file mode 100644
index 733761671a04..000000000000
--- a/library/std/src/sync/mpsc/sync.rs
+++ /dev/null
@@ -1,495 +0,0 @@
-use self::Blocker::*;
-/// Synchronous channels/ports
-///
-/// This channel implementation differs significantly from the asynchronous
-/// implementations found next to it (oneshot/stream/share). This is an
-/// implementation of a synchronous, bounded buffer channel.
-///
-/// Each channel is created with some amount of backing buffer, and sends will
-/// *block* until buffer space becomes available. A buffer size of 0 is valid,
-/// which means that every successful send is paired with a successful recv.
-///
-/// This flavor of channels defines a new `send_opt` method for channels which
-/// is the method by which a message is sent but the thread does not panic if it
-/// cannot be delivered.
-///
-/// Another major difference is that send() will *always* return back the data
-/// if it couldn't be sent. This is because it is deterministically known when
-/// the data is received and when it is not received.
-///
-/// Implementation-wise, it can all be summed up with "use a mutex plus some
-/// logic". The mutex used here is an OS native mutex, meaning that no user code
-/// is run inside of the mutex (to prevent context switching). This
-/// implementation shares almost all code for the buffered and unbuffered cases
-/// of a synchronous channel. There are a few branches for the unbuffered case,
-/// but they're mostly just relevant to blocking senders.
-pub use self::Failure::*;
-
-use core::intrinsics::abort;
-use core::mem;
-use core::ptr;
-
-use crate::sync::atomic::{AtomicUsize, Ordering};
-use crate::sync::mpsc::blocking::{self, SignalToken, WaitToken};
-use crate::sync::{Mutex, MutexGuard};
-use crate::time::Instant;
-
-const MAX_REFCOUNT: usize = (isize::MAX) as usize;
-
-pub struct Packet<T> {
-    /// Only field outside of the mutex. Just done for kicks, but mainly because
-    /// the other shared channel already had the code implemented
-    channels: AtomicUsize,
-
-    lock: Mutex<State<T>>,
-}
-
-unsafe impl<T: Send> Send for Packet<T> {}
-
-unsafe impl<T: Send> Sync for Packet<T> {}
-
-struct State<T> {
-    disconnected: bool, // Is the channel disconnected yet?
-    queue: Queue,       // queue of senders waiting to send data
-    blocker: Blocker,   // currently blocked thread on this channel
-    buf: Buffer<T>,     // storage for buffered messages
-    cap: usize,         // capacity of this channel
-
-    /// A curious flag used to indicate whether a sender failed or succeeded in
-    /// blocking. This is used to transmit information back to the thread that it
-    /// must dequeue its message from the buffer because it was not received.
-    /// This is only relevant in the 0-buffer case. This obviously cannot be
-    /// safely constructed, but it's guaranteed to always have a valid pointer
-    /// value.
-    canceled: Option<&'static mut bool>,
-}
-
-unsafe impl<T: Send> Send for State<T> {}
-
-/// Possible flavors of threads who can be blocked on this channel.
-enum Blocker {
-    BlockedSender(SignalToken),
-    BlockedReceiver(SignalToken),
-    NoneBlocked,
-}
-
-/// Simple queue for threading threads together. Nodes are stack-allocated, so
-/// this structure is not safe at all
-struct Queue {
-    head: *mut Node,
-    tail: *mut Node,
-}
-
-struct Node {
-    token: Option<SignalToken>,
-    next: *mut Node,
-}
-
-unsafe impl Send for Node {}
-
-/// A simple ring-buffer
-struct Buffer<T> {
-    buf: Vec<Option<T>>,
-    start: usize,
-    size: usize,
-}
-
-#[derive(Debug)]
-pub enum Failure {
-    Empty,
-    Disconnected,
-}
-
-/// Atomically blocks the current thread, placing it into `slot`, unlocking `lock`
-/// in the meantime. This re-locks the mutex upon returning.
-fn wait<'a, 'b, T>(
-    lock: &'a Mutex<State<T>>,
-    mut guard: MutexGuard<'b, State<T>>,
-    f: fn(SignalToken) -> Blocker,
-) -> MutexGuard<'a, State<T>> {
-    let (wait_token, signal_token) = blocking::tokens();
-    match mem::replace(&mut guard.blocker, f(signal_token)) {
-        NoneBlocked => {}
-        _ => unreachable!(),
-    }
-    drop(guard); // unlock
-    wait_token.wait(); // block
-    lock.lock().unwrap() // relock
-}
-
-/// Same as wait, but waiting at most until `deadline`.
-fn wait_timeout_receiver<'a, 'b, T>(
-    lock: &'a Mutex<State<T>>,
-    deadline: Instant,
-    mut guard: MutexGuard<'b, State<T>>,
-    success: &mut bool,
-) -> MutexGuard<'a, State<T>> {
-    let (wait_token, signal_token) = blocking::tokens();
-    match mem::replace(&mut guard.blocker, BlockedReceiver(signal_token)) {
-        NoneBlocked => {}
-        _ => unreachable!(),
-    }
-    drop(guard); // unlock
-    *success = wait_token.wait_max_until(deadline); // block
-    let mut new_guard = lock.lock().unwrap(); // relock
-    if !*success {
-        abort_selection(&mut new_guard);
-    }
-    new_guard
-}
-
-fn abort_selection<T>(guard: &mut MutexGuard<'_, State<T>>) -> bool {
-    match mem::replace(&mut guard.blocker, NoneBlocked) {
-        NoneBlocked => true,
-        BlockedSender(token) => {
-            guard.blocker = BlockedSender(token);
-            true
-        }
-        BlockedReceiver(token) => {
-            drop(token);
-            false
-        }
-    }
-}
-
-/// Wakes up a thread, dropping the lock at the correct time
-fn wakeup<T>(token: SignalToken, guard: MutexGuard<'_, State<T>>) {
-    // We need to be careful to wake up the waiting thread *outside* of the mutex
-    // in case it incurs a context switch.
-    drop(guard);
-    token.signal();
-}
-
-impl<T> Packet<T> {
-    pub fn new(capacity: usize) -> Packet<T> {
-        Packet {
-            channels: AtomicUsize::new(1),
-            lock: Mutex::new(State {
-                disconnected: false,
-                blocker: NoneBlocked,
-                cap: capacity,
-                canceled: None,
-                queue: Queue { head: ptr::null_mut(), tail: ptr::null_mut() },
-                buf: Buffer {
-                    buf: (0..capacity + if capacity == 0 { 1 } else { 0 }).map(|_| None).collect(),
-                    start: 0,
-                    size: 0,
-                },
-            }),
-        }
-    }
-
-    // wait until a send slot is available, returning locked access to
-    // the channel state.
-    fn acquire_send_slot(&self) -> MutexGuard<'_, State<T>> {
-        let mut node = Node { token: None, next: ptr::null_mut() };
-        loop {
-            let mut guard = self.lock.lock().unwrap();
-            // are we ready to go?
-            if guard.disconnected || guard.buf.size() < guard.buf.capacity() {
-                return guard;
-            }
-            // no room; actually block
-            let wait_token = guard.queue.enqueue(&mut node);
-            drop(guard);
-            wait_token.wait();
-        }
-    }
-
-    pub fn send(&self, t: T) -> Result<(), T> {
-        let mut guard = self.acquire_send_slot();
-        if guard.disconnected {
-            return Err(t);
-        }
-        guard.buf.enqueue(t);
-
-        match mem::replace(&mut guard.blocker, NoneBlocked) {
-            // if our capacity is 0, then we need to wait for a receiver to be
-            // available to take our data. After waiting, we check again to make
-            // sure the port didn't go away in the meantime. If it did, we need
-            // to hand back our data.
-            NoneBlocked if guard.cap == 0 => {
-                let mut canceled = false;
-                assert!(guard.canceled.is_none());
-                guard.canceled = Some(unsafe { mem::transmute(&mut canceled) });
-                let mut guard = wait(&self.lock, guard, BlockedSender);
-                if canceled { Err(guard.buf.dequeue()) } else { Ok(()) }
-            }
-
-            // success, we buffered some data
-            NoneBlocked => Ok(()),
-
-            // success, someone's about to receive our buffered data.
-            BlockedReceiver(token) => {
-                wakeup(token, guard);
-                Ok(())
-            }
-
-            BlockedSender(..) => panic!("lolwut"),
-        }
-    }
-
-    pub fn try_send(&self, t: T) -> Result<(), super::TrySendError<T>> {
-        let mut guard = self.lock.lock().unwrap();
-        if guard.disconnected {
-            Err(super::TrySendError::Disconnected(t))
-        } else if guard.buf.size() == guard.buf.capacity() {
-            Err(super::TrySendError::Full(t))
-        } else if guard.cap == 0 {
-            // With capacity 0, even though we have buffer space we can't
-            // transfer the data unless there's a receiver waiting.
-            match mem::replace(&mut guard.blocker, NoneBlocked) {
-                NoneBlocked => Err(super::TrySendError::Full(t)),
-                BlockedSender(..) => unreachable!(),
-                BlockedReceiver(token) => {
-                    guard.buf.enqueue(t);
-                    wakeup(token, guard);
-                    Ok(())
-                }
-            }
-        } else {
-            // If the buffer has some space and the capacity isn't 0, then we
-            // just enqueue the data for later retrieval, ensuring to wake up
-            // any blocked receiver if there is one.
-            assert!(guard.buf.size() < guard.buf.capacity());
-            guard.buf.enqueue(t);
-            match mem::replace(&mut guard.blocker, NoneBlocked) {
-                BlockedReceiver(token) => wakeup(token, guard),
-                NoneBlocked => {}
-                BlockedSender(..) => unreachable!(),
-            }
-            Ok(())
-        }
-    }
-
-    // Receives a message from this channel
-    //
-    // When reading this, remember that there can only ever be one receiver at
-    // time.
-    pub fn recv(&self, deadline: Option<Instant>) -> Result<T, Failure> {
-        let mut guard = self.lock.lock().unwrap();
-
-        let mut woke_up_after_waiting = false;
-        // Wait for the buffer to have something in it. No need for a
-        // while loop because we're the only receiver.
-        if !guard.disconnected && guard.buf.size() == 0 {
-            if let Some(deadline) = deadline {
-                guard =
-                    wait_timeout_receiver(&self.lock, deadline, guard, &mut woke_up_after_waiting);
-            } else {
-                guard = wait(&self.lock, guard, BlockedReceiver);
-                woke_up_after_waiting = true;
-            }
-        }
-
-        // N.B., channel could be disconnected while waiting, so the order of
-        // these conditionals is important.
-        if guard.disconnected && guard.buf.size() == 0 {
-            return Err(Disconnected);
-        }
-
-        // Pick up the data, wake up our neighbors, and carry on
-        assert!(guard.buf.size() > 0 || (deadline.is_some() && !woke_up_after_waiting));
-
-        if guard.buf.size() == 0 {
-            return Err(Empty);
-        }
-
-        let ret = guard.buf.dequeue();
-        self.wakeup_senders(woke_up_after_waiting, guard);
-        Ok(ret)
-    }
-
-    pub fn try_recv(&self) -> Result<T, Failure> {
-        let mut guard = self.lock.lock().unwrap();
-
-        // Easy cases first
-        if guard.disconnected && guard.buf.size() == 0 {
-            return Err(Disconnected);
-        }
-        if guard.buf.size() == 0 {
-            return Err(Empty);
-        }
-
-        // Be sure to wake up neighbors
-        let ret = Ok(guard.buf.dequeue());
-        self.wakeup_senders(false, guard);
-        ret
-    }
-
-    // Wake up pending senders after some data has been received
-    //
-    // * `waited` - flag if the receiver blocked to receive some data, or if it
-    //              just picked up some data on the way out
-    // * `guard` - the lock guard that is held over this channel's lock
-    fn wakeup_senders(&self, waited: bool, mut guard: MutexGuard<'_, State<T>>) {
-        let pending_sender1: Option<SignalToken> = guard.queue.dequeue();
-
-        // If this is a no-buffer channel (cap == 0), then if we didn't wait we
-        // need to ACK the sender. If we waited, then the sender waking us up
-        // was already the ACK.
-        let pending_sender2 = if guard.cap == 0 && !waited {
-            match mem::replace(&mut guard.blocker, NoneBlocked) {
-                NoneBlocked => None,
-                BlockedReceiver(..) => unreachable!(),
-                BlockedSender(token) => {
-                    guard.canceled.take();
-                    Some(token)
-                }
-            }
-        } else {
-            None
-        };
-        mem::drop(guard);
-
-        // only outside of the lock do we wake up the pending threads
-        if let Some(token) = pending_sender1 {
-            token.signal();
-        }
-        if let Some(token) = pending_sender2 {
-            token.signal();
-        }
-    }
-
-    // Prepares this shared packet for a channel clone, essentially just bumping
-    // a refcount.
-    pub fn clone_chan(&self) {
-        let old_count = self.channels.fetch_add(1, Ordering::SeqCst);
-
-        // See comments on Arc::clone() on why we do this (for `mem::forget`).
-        if old_count > MAX_REFCOUNT {
-            abort();
-        }
-    }
-
-    pub fn drop_chan(&self) {
-        // Only flag the channel as disconnected if we're the last channel
-        match self.channels.fetch_sub(1, Ordering::SeqCst) {
-            1 => {}
-            _ => return,
-        }
-
-        // Not much to do other than wake up a receiver if one's there
-        let mut guard = self.lock.lock().unwrap();
-        if guard.disconnected {
-            return;
-        }
-        guard.disconnected = true;
-        match mem::replace(&mut guard.blocker, NoneBlocked) {
-            NoneBlocked => {}
-            BlockedSender(..) => unreachable!(),
-            BlockedReceiver(token) => wakeup(token, guard),
-        }
-    }
-
-    pub fn drop_port(&self) {
-        let mut guard = self.lock.lock().unwrap();
-
-        if guard.disconnected {
-            return;
-        }
-        guard.disconnected = true;
-
-        // If the capacity is 0, then the sender may want its data back after
-        // we're disconnected. Otherwise it's now our responsibility to destroy
-        // the buffered data. As with many other portions of this code, this
-        // needs to be careful to destroy the data *outside* of the lock to
-        // prevent deadlock.
-        let _data = if guard.cap != 0 { mem::take(&mut guard.buf.buf) } else { Vec::new() };
-        let mut queue =
-            mem::replace(&mut guard.queue, Queue { head: ptr::null_mut(), tail: ptr::null_mut() });
-
-        let waiter = match mem::replace(&mut guard.blocker, NoneBlocked) {
-            NoneBlocked => None,
-            BlockedSender(token) => {
-                *guard.canceled.take().unwrap() = true;
-                Some(token)
-            }
-            BlockedReceiver(..) => unreachable!(),
-        };
-        mem::drop(guard);
-
-        while let Some(token) = queue.dequeue() {
-            token.signal();
-        }
-        if let Some(token) = waiter {
-            token.signal();
-        }
-    }
-}
-
-impl<T> Drop for Packet<T> {
-    fn drop(&mut self) {
-        assert_eq!(self.channels.load(Ordering::SeqCst), 0);
-        let mut guard = self.lock.lock().unwrap();
-        assert!(guard.queue.dequeue().is_none());
-        assert!(guard.canceled.is_none());
-    }
-}
-
-////////////////////////////////////////////////////////////////////////////////
-// Buffer, a simple ring buffer backed by Vec<T>
-////////////////////////////////////////////////////////////////////////////////
-
-impl<T> Buffer<T> {
-    fn enqueue(&mut self, t: T) {
-        let pos = (self.start + self.size) % self.buf.len();
-        self.size += 1;
-        let prev = mem::replace(&mut self.buf[pos], Some(t));
-        assert!(prev.is_none());
-    }
-
-    fn dequeue(&mut self) -> T {
-        let start = self.start;
-        self.size -= 1;
-        self.start = (self.start + 1) % self.buf.len();
-        let result = &mut self.buf[start];
-        result.take().unwrap()
-    }
-
-    fn size(&self) -> usize {
-        self.size
-    }
-    fn capacity(&self) -> usize {
-        self.buf.len()
-    }
-}
-
-////////////////////////////////////////////////////////////////////////////////
-// Queue, a simple queue to enqueue threads with (stack-allocated nodes)
-////////////////////////////////////////////////////////////////////////////////
-
-impl Queue {
-    fn enqueue(&mut self, node: &mut Node) -> WaitToken {
-        let (wait_token, signal_token) = blocking::tokens();
-        node.token = Some(signal_token);
-        node.next = ptr::null_mut();
-
-        if self.tail.is_null() {
-            self.head = node as *mut Node;
-            self.tail = node as *mut Node;
-        } else {
-            unsafe {
-                (*self.tail).next = node as *mut Node;
-                self.tail = node as *mut Node;
-            }
-        }
-
-        wait_token
-    }
-
-    fn dequeue(&mut self) -> Option<SignalToken> {
-        if self.head.is_null() {
-            return None;
-        }
-        let node = self.head;
-        self.head = unsafe { (*node).next };
-        if self.head.is_null() {
-            self.tail = ptr::null_mut();
-        }
-        unsafe {
-            (*node).next = ptr::null_mut();
-            Some((*node).token.take().unwrap())
-        }
-    }
-}
diff --git a/library/std/src/sync/mpsc/tests.rs b/library/std/src/sync/mpsc/tests.rs
index f6d0796f604f..82c52eb4fef4 100644
--- a/library/std/src/sync/mpsc/tests.rs
+++ b/library/std/src/sync/mpsc/tests.rs
@@ -706,3 +706,17 @@ fn issue_32114() {
     let _ = tx.send(123);
     assert_eq!(tx.send(123), Err(SendError(123)));
 }
+
+#[test]
+fn issue_39364() {
+    let (tx, rx) = channel::<()>();
+    let t = thread::spawn(move || {
+        thread::sleep(Duration::from_millis(300));
+        let _ = tx.clone();
+        crate::mem::forget(tx);
+    });
+
+    let _ = rx.recv_timeout(Duration::from_millis(500));
+    t.join().unwrap();
+    let _ = rx.recv_timeout(Duration::from_millis(500));
+}
diff --git a/library/std/src/sync/mutex.rs b/library/std/src/sync/mutex.rs
index de851c8fbbed..065045f44206 100644
--- a/library/std/src/sync/mutex.rs
+++ b/library/std/src/sync/mutex.rs
@@ -5,7 +5,7 @@ use crate::cell::UnsafeCell;
 use crate::fmt;
 use crate::ops::{Deref, DerefMut};
 use crate::sync::{poison, LockResult, TryLockError, TryLockResult};
-use crate::sys_common::mutex as sys;
+use crate::sys::locks as sys;
 
 /// A mutual exclusion primitive useful for protecting shared data
 ///
@@ -163,7 +163,7 @@ use crate::sys_common::mutex as sys;
 #[stable(feature = "rust1", since = "1.0.0")]
 #[cfg_attr(not(test), rustc_diagnostic_item = "Mutex")]
 pub struct Mutex<T: ?Sized> {
-    inner: sys::MovableMutex,
+    inner: sys::Mutex,
     poison: poison::Flag,
     data: UnsafeCell<T>,
 }
@@ -217,11 +217,7 @@ impl<T> Mutex<T> {
     #[rustc_const_stable(feature = "const_locks", since = "1.63.0")]
     #[inline]
     pub const fn new(t: T) -> Mutex<T> {
-        Mutex {
-            inner: sys::MovableMutex::new(),
-            poison: poison::Flag::new(),
-            data: UnsafeCell::new(t),
-        }
+        Mutex { inner: sys::Mutex::new(), poison: poison::Flag::new(), data: UnsafeCell::new(t) }
     }
 }
 
@@ -264,7 +260,7 @@ impl<T: ?Sized> Mutex<T> {
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn lock(&self) -> LockResult<MutexGuard<'_, T>> {
         unsafe {
-            self.inner.raw_lock();
+            self.inner.lock();
             MutexGuard::new(self)
         }
     }
@@ -526,7 +522,7 @@ impl<T: ?Sized> Drop for MutexGuard<'_, T> {
     fn drop(&mut self) {
         unsafe {
             self.lock.poison.done(&self.poison);
-            self.lock.inner.raw_unlock();
+            self.lock.inner.unlock();
         }
     }
 }
@@ -545,7 +541,7 @@ impl<T: ?Sized + fmt::Display> fmt::Display for MutexGuard<'_, T> {
     }
 }
 
-pub fn guard_lock<'a, T: ?Sized>(guard: &MutexGuard<'a, T>) -> &'a sys::MovableMutex {
+pub fn guard_lock<'a, T: ?Sized>(guard: &MutexGuard<'a, T>) -> &'a sys::Mutex {
     &guard.lock.inner
 }
 
diff --git a/library/std/src/sync/rwlock.rs b/library/std/src/sync/rwlock.rs
index 8b387760768c..7c409cb3e977 100644
--- a/library/std/src/sync/rwlock.rs
+++ b/library/std/src/sync/rwlock.rs
@@ -6,7 +6,7 @@ use crate::fmt;
 use crate::ops::{Deref, DerefMut};
 use crate::ptr::NonNull;
 use crate::sync::{poison, LockResult, TryLockError, TryLockResult};
-use crate::sys_common::rwlock as sys;
+use crate::sys::locks as sys;
 
 /// A reader-writer lock
 ///
@@ -78,7 +78,7 @@ use crate::sys_common::rwlock as sys;
 #[stable(feature = "rust1", since = "1.0.0")]
 #[cfg_attr(not(test), rustc_diagnostic_item = "RwLock")]
 pub struct RwLock<T: ?Sized> {
-    inner: sys::MovableRwLock,
+    inner: sys::RwLock,
     poison: poison::Flag,
     data: UnsafeCell<T>,
 }
@@ -109,7 +109,7 @@ pub struct RwLockReadGuard<'a, T: ?Sized + 'a> {
     // `NonNull` is also covariant over `T`, just like we would have with `&T`. `NonNull`
     // is preferable over `const* T` to allow for niche optimization.
     data: NonNull<T>,
-    inner_lock: &'a sys::MovableRwLock,
+    inner_lock: &'a sys::RwLock,
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
@@ -158,11 +158,7 @@ impl<T> RwLock<T> {
     #[rustc_const_stable(feature = "const_locks", since = "1.63.0")]
     #[inline]
     pub const fn new(t: T) -> RwLock<T> {
-        RwLock {
-            inner: sys::MovableRwLock::new(),
-            poison: poison::Flag::new(),
-            data: UnsafeCell::new(t),
-        }
+        RwLock { inner: sys::RwLock::new(), poison: poison::Flag::new(), data: UnsafeCell::new(t) }
     }
 }
 
diff --git a/library/std/src/sys/hermit/mod.rs b/library/std/src/sys/hermit/mod.rs
index e6534df8938e..6811fadb0188 100644
--- a/library/std/src/sys/hermit/mod.rs
+++ b/library/std/src/sys/hermit/mod.rs
@@ -51,9 +51,9 @@ pub mod locks {
     mod futex_condvar;
     mod futex_mutex;
     mod futex_rwlock;
-    pub(crate) use futex_condvar::MovableCondvar;
-    pub(crate) use futex_mutex::{MovableMutex, Mutex};
-    pub(crate) use futex_rwlock::{MovableRwLock, RwLock};
+    pub(crate) use futex_condvar::Condvar;
+    pub(crate) use futex_mutex::Mutex;
+    pub(crate) use futex_rwlock::RwLock;
 }
 
 use crate::io::ErrorKind;
diff --git a/library/std/src/sys/itron/condvar.rs b/library/std/src/sys/itron/condvar.rs
index 008cd8fb1e39..f70aa434e483 100644
--- a/library/std/src/sys/itron/condvar.rs
+++ b/library/std/src/sys/itron/condvar.rs
@@ -12,18 +12,13 @@ pub struct Condvar {
 unsafe impl Send for Condvar {}
 unsafe impl Sync for Condvar {}
 
-pub type MovableCondvar = Condvar;
-
 impl Condvar {
     #[inline]
     pub const fn new() -> Condvar {
         Condvar { waiters: SpinMutex::new(waiter_queue::WaiterQueue::new()) }
     }
 
-    #[inline]
-    pub unsafe fn init(&mut self) {}
-
-    pub unsafe fn notify_one(&self) {
+    pub fn notify_one(&self) {
         self.waiters.with_locked(|waiters| {
             if let Some(task) = waiters.pop_front() {
                 // Unpark the task
@@ -39,7 +34,7 @@ impl Condvar {
         });
     }
 
-    pub unsafe fn notify_all(&self) {
+    pub fn notify_all(&self) {
         self.waiters.with_locked(|waiters| {
             while let Some(task) = waiters.pop_front() {
                 // Unpark the task
diff --git a/library/std/src/sys/itron/mutex.rs b/library/std/src/sys/itron/mutex.rs
index 085662e6d44b..f2eed8e771c4 100644
--- a/library/std/src/sys/itron/mutex.rs
+++ b/library/std/src/sys/itron/mutex.rs
@@ -11,8 +11,6 @@ pub struct Mutex {
     mtx: SpinIdOnceCell<()>,
 }
 
-pub type MovableMutex = Mutex;
-
 /// Create a mutex object. This function never panics.
 fn new_mtx() -> Result<abi::ID, ItronError> {
     ItronError::err_if_negative(unsafe {
@@ -39,7 +37,7 @@ impl Mutex {
         }
     }
 
-    pub unsafe fn lock(&self) {
+    pub fn lock(&self) {
         let mtx = self.raw();
         expect_success(unsafe { abi::loc_mtx(mtx) }, &"loc_mtx");
     }
@@ -49,7 +47,7 @@ impl Mutex {
         expect_success_aborting(unsafe { abi::unl_mtx(mtx) }, &"unl_mtx");
     }
 
-    pub unsafe fn try_lock(&self) -> bool {
+    pub fn try_lock(&self) -> bool {
         let mtx = self.raw();
         match unsafe { abi::ploc_mtx(mtx) } {
             abi::E_TMOUT => false,
diff --git a/library/std/src/sys/sgx/condvar.rs b/library/std/src/sys/sgx/condvar.rs
index 36534e0eff3f..aa1174664aeb 100644
--- a/library/std/src/sys/sgx/condvar.rs
+++ b/library/std/src/sys/sgx/condvar.rs
@@ -4,42 +4,43 @@ use crate::time::Duration;
 
 use super::waitqueue::{SpinMutex, WaitQueue, WaitVariable};
 
+/// FIXME: `UnsafeList` is not movable.
+struct AllocatedCondvar(SpinMutex<WaitVariable<()>>);
+
 pub struct Condvar {
-    inner: SpinMutex<WaitVariable<()>>,
+    inner: LazyBox<AllocatedCondvar>,
 }
 
-pub(crate) type MovableCondvar = LazyBox<Condvar>;
-
-impl LazyInit for Condvar {
+impl LazyInit for AllocatedCondvar {
     fn init() -> Box<Self> {
-        Box::new(Self::new())
+        Box::new(AllocatedCondvar(SpinMutex::new(WaitVariable::new(()))))
     }
 }
 
 impl Condvar {
     pub const fn new() -> Condvar {
-        Condvar { inner: SpinMutex::new(WaitVariable::new(())) }
+        Condvar { inner: LazyBox::new() }
     }
 
     #[inline]
-    pub unsafe fn notify_one(&self) {
-        let _ = WaitQueue::notify_one(self.inner.lock());
+    pub fn notify_one(&self) {
+        let _ = WaitQueue::notify_one(self.inner.0.lock());
     }
 
     #[inline]
-    pub unsafe fn notify_all(&self) {
-        let _ = WaitQueue::notify_all(self.inner.lock());
+    pub fn notify_all(&self) {
+        let _ = WaitQueue::notify_all(self.inner.0.lock());
     }
 
     pub unsafe fn wait(&self, mutex: &Mutex) {
-        let guard = self.inner.lock();
+        let guard = self.inner.0.lock();
         WaitQueue::wait(guard, || unsafe { mutex.unlock() });
-        unsafe { mutex.lock() }
+        mutex.lock()
     }
 
     pub unsafe fn wait_timeout(&self, mutex: &Mutex, dur: Duration) -> bool {
-        let success = WaitQueue::wait_timeout(&self.inner, dur, || unsafe { mutex.unlock() });
-        unsafe { mutex.lock() };
+        let success = WaitQueue::wait_timeout(&self.inner.0, dur, || unsafe { mutex.unlock() });
+        mutex.lock();
         success
     }
 }
diff --git a/library/std/src/sys/sgx/mutex.rs b/library/std/src/sys/sgx/mutex.rs
index aa747d56b0d3..0dbf020ebe06 100644
--- a/library/std/src/sys/sgx/mutex.rs
+++ b/library/std/src/sys/sgx/mutex.rs
@@ -1,28 +1,28 @@
 use super::waitqueue::{try_lock_or_false, SpinMutex, WaitQueue, WaitVariable};
 use crate::sys_common::lazy_box::{LazyBox, LazyInit};
 
+/// FIXME: `UnsafeList` is not movable.
+struct AllocatedMutex(SpinMutex<WaitVariable<bool>>);
+
 pub struct Mutex {
-    inner: SpinMutex<WaitVariable<bool>>,
+    inner: LazyBox<AllocatedMutex>,
 }
 
-// not movable: see UnsafeList implementation
-pub(crate) type MovableMutex = LazyBox<Mutex>;
-
-impl LazyInit for Mutex {
+impl LazyInit for AllocatedMutex {
     fn init() -> Box<Self> {
-        Box::new(Self::new())
+        Box::new(AllocatedMutex(SpinMutex::new(WaitVariable::new(false))))
     }
 }
 
 // Implementation according to “Operating Systems: Three Easy Pieces”, chapter 28
 impl Mutex {
     pub const fn new() -> Mutex {
-        Mutex { inner: SpinMutex::new(WaitVariable::new(false)) }
+        Mutex { inner: LazyBox::new() }
     }
 
     #[inline]
-    pub unsafe fn lock(&self) {
-        let mut guard = self.inner.lock();
+    pub fn lock(&self) {
+        let mut guard = self.inner.0.lock();
         if *guard.lock_var() {
             // Another thread has the lock, wait
             WaitQueue::wait(guard, || {})
@@ -35,7 +35,7 @@ impl Mutex {
 
     #[inline]
     pub unsafe fn unlock(&self) {
-        let guard = self.inner.lock();
+        let guard = self.inner.0.lock();
         if let Err(mut guard) = WaitQueue::notify_one(guard) {
             // No other waiters, unlock
             *guard.lock_var_mut() = false;
@@ -45,8 +45,8 @@ impl Mutex {
     }
 
     #[inline]
-    pub unsafe fn try_lock(&self) -> bool {
-        let mut guard = try_lock_or_false!(self.inner);
+    pub fn try_lock(&self) -> bool {
+        let mut guard = try_lock_or_false!(self.inner.0);
         if *guard.lock_var() {
             // Another thread has the lock
             false
diff --git a/library/std/src/sys/sgx/rwlock.rs b/library/std/src/sys/sgx/rwlock.rs
index a97fb9ab026f..d89de18ca5ff 100644
--- a/library/std/src/sys/sgx/rwlock.rs
+++ b/library/std/src/sys/sgx/rwlock.rs
@@ -7,42 +7,45 @@ use crate::sys_common::lazy_box::{LazyBox, LazyInit};
 use super::waitqueue::{
     try_lock_or_false, NotifiedTcs, SpinMutex, SpinMutexGuard, WaitQueue, WaitVariable,
 };
-use crate::mem;
+use crate::alloc::Layout;
 
-pub struct RwLock {
+struct AllocatedRwLock {
     readers: SpinMutex<WaitVariable<Option<NonZeroUsize>>>,
     writer: SpinMutex<WaitVariable<bool>>,
 }
 
-pub(crate) type MovableRwLock = LazyBox<RwLock>;
+pub struct RwLock {
+    inner: LazyBox<AllocatedRwLock>,
+}
 
-impl LazyInit for RwLock {
+impl LazyInit for AllocatedRwLock {
     fn init() -> Box<Self> {
-        Box::new(Self::new())
+        Box::new(AllocatedRwLock {
+            readers: SpinMutex::new(WaitVariable::new(None)),
+            writer: SpinMutex::new(WaitVariable::new(false)),
+        })
     }
 }
 
-// Check at compile time that RwLock size matches C definition (see test_c_rwlock_initializer below)
-//
-// # Safety
-// Never called, as it is a compile time check.
-#[allow(dead_code)]
-unsafe fn rw_lock_size_assert(r: RwLock) {
-    unsafe { mem::transmute::<RwLock, [u8; 144]>(r) };
-}
+// Check at compile time that RwLock's size and alignment matches the C definition
+// in libunwind (see also `test_c_rwlock_initializer` in `tests`).
+const _: () = {
+    let rust = Layout::new::<RwLock>();
+    let c = Layout::new::<*mut ()>();
+    assert!(rust.size() == c.size());
+    assert!(rust.align() == c.align());
+};
 
 impl RwLock {
     pub const fn new() -> RwLock {
-        RwLock {
-            readers: SpinMutex::new(WaitVariable::new(None)),
-            writer: SpinMutex::new(WaitVariable::new(false)),
-        }
+        RwLock { inner: LazyBox::new() }
     }
 
     #[inline]
-    pub unsafe fn read(&self) {
-        let mut rguard = self.readers.lock();
-        let wguard = self.writer.lock();
+    pub fn read(&self) {
+        let lock = &*self.inner;
+        let mut rguard = lock.readers.lock();
+        let wguard = lock.writer.lock();
         if *wguard.lock_var() || !wguard.queue_empty() {
             // Another thread has or is waiting for the write lock, wait
             drop(wguard);
@@ -57,8 +60,9 @@ impl RwLock {
 
     #[inline]
     pub unsafe fn try_read(&self) -> bool {
-        let mut rguard = try_lock_or_false!(self.readers);
-        let wguard = try_lock_or_false!(self.writer);
+        let lock = &*self.inner;
+        let mut rguard = try_lock_or_false!(lock.readers);
+        let wguard = try_lock_or_false!(lock.writer);
         if *wguard.lock_var() || !wguard.queue_empty() {
             // Another thread has or is waiting for the write lock
             false
@@ -71,9 +75,10 @@ impl RwLock {
     }
 
     #[inline]
-    pub unsafe fn write(&self) {
-        let rguard = self.readers.lock();
-        let mut wguard = self.writer.lock();
+    pub fn write(&self) {
+        let lock = &*self.inner;
+        let rguard = lock.readers.lock();
+        let mut wguard = lock.writer.lock();
         if *wguard.lock_var() || rguard.lock_var().is_some() {
             // Another thread has the lock, wait
             drop(rguard);
@@ -86,9 +91,10 @@ impl RwLock {
     }
 
     #[inline]
-    pub unsafe fn try_write(&self) -> bool {
-        let rguard = try_lock_or_false!(self.readers);
-        let mut wguard = try_lock_or_false!(self.writer);
+    pub fn try_write(&self) -> bool {
+        let lock = &*self.inner;
+        let rguard = try_lock_or_false!(lock.readers);
+        let mut wguard = try_lock_or_false!(lock.writer);
         if *wguard.lock_var() || rguard.lock_var().is_some() {
             // Another thread has the lock
             false
@@ -122,8 +128,9 @@ impl RwLock {
 
     #[inline]
     pub unsafe fn read_unlock(&self) {
-        let rguard = self.readers.lock();
-        let wguard = self.writer.lock();
+        let lock = &*self.inner;
+        let rguard = lock.readers.lock();
+        let wguard = lock.writer.lock();
         unsafe { self.__read_unlock(rguard, wguard) };
     }
 
@@ -158,8 +165,9 @@ impl RwLock {
 
     #[inline]
     pub unsafe fn write_unlock(&self) {
-        let rguard = self.readers.lock();
-        let wguard = self.writer.lock();
+        let lock = &*self.inner;
+        let rguard = lock.readers.lock();
+        let wguard = lock.writer.lock();
         unsafe { self.__write_unlock(rguard, wguard) };
     }
 
@@ -167,8 +175,9 @@ impl RwLock {
     #[inline]
     #[cfg_attr(test, allow(dead_code))]
     unsafe fn unlock(&self) {
-        let rguard = self.readers.lock();
-        let wguard = self.writer.lock();
+        let lock = &*self.inner;
+        let rguard = lock.readers.lock();
+        let wguard = lock.writer.lock();
         if *wguard.lock_var() == true {
             unsafe { self.__write_unlock(rguard, wguard) };
         } else {
@@ -201,6 +210,7 @@ pub unsafe extern "C" fn __rust_rwlock_wrlock(p: *mut RwLock) -> i32 {
     unsafe { (*p).write() };
     return 0;
 }
+
 #[cfg(not(test))]
 #[no_mangle]
 pub unsafe extern "C" fn __rust_rwlock_unlock(p: *mut RwLock) -> i32 {
diff --git a/library/std/src/sys/sgx/rwlock/tests.rs b/library/std/src/sys/sgx/rwlock/tests.rs
index 4799961154a4..5fd6670afd43 100644
--- a/library/std/src/sys/sgx/rwlock/tests.rs
+++ b/library/std/src/sys/sgx/rwlock/tests.rs
@@ -1,22 +1,12 @@
 use super::*;
+use crate::ptr;
 
 // Verify that the byte pattern libunwind uses to initialize an RwLock is
 // equivalent to the value of RwLock::new(). If the value changes,
 // `src/UnwindRustSgx.h` in libunwind needs to be changed too.
 #[test]
 fn test_c_rwlock_initializer() {
-    #[rustfmt::skip]
-    const C_RWLOCK_INIT: &[u8] = &[
-        /* 0x00 */ 0x1, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
-        /* 0x10 */ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x2, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
-        /* 0x20 */ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
-        /* 0x30 */ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
-        /* 0x40 */ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x1, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
-        /* 0x50 */ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
-        /* 0x60 */ 0x2, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
-        /* 0x70 */ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
-        /* 0x80 */ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
-    ];
+    const C_RWLOCK_INIT: *mut () = ptr::null_mut();
 
     // For the test to work, we need the padding/unused bytes in RwLock to be
     // initialized as 0. In practice, this is the case with statics.
@@ -26,6 +16,6 @@ fn test_c_rwlock_initializer() {
         // If the assertion fails, that not necessarily an issue with the value
         // of C_RWLOCK_INIT. It might just be an issue with the way padding
         // bytes are initialized in the test code.
-        assert_eq!(&crate::mem::transmute_copy::<_, [u8; 144]>(&RUST_RWLOCK_INIT), C_RWLOCK_INIT);
+        assert_eq!(crate::mem::transmute_copy::<_, *mut ()>(&RUST_RWLOCK_INIT), C_RWLOCK_INIT);
     };
 }
diff --git a/library/std/src/sys/solid/rwlock.rs b/library/std/src/sys/solid/rwlock.rs
index 0a770cf03f2f..ecb4eb83b9b0 100644
--- a/library/std/src/sys/solid/rwlock.rs
+++ b/library/std/src/sys/solid/rwlock.rs
@@ -12,8 +12,6 @@ pub struct RwLock {
     rwl: SpinIdOnceCell<()>,
 }
 
-pub type MovableRwLock = RwLock;
-
 // Safety: `num_readers` is protected by `mtx_num_readers`
 unsafe impl Send for RwLock {}
 unsafe impl Sync for RwLock {}
@@ -37,13 +35,13 @@ impl RwLock {
     }
 
     #[inline]
-    pub unsafe fn read(&self) {
+    pub fn read(&self) {
         let rwl = self.raw();
         expect_success(unsafe { abi::rwl_loc_rdl(rwl) }, &"rwl_loc_rdl");
     }
 
     #[inline]
-    pub unsafe fn try_read(&self) -> bool {
+    pub fn try_read(&self) -> bool {
         let rwl = self.raw();
         match unsafe { abi::rwl_ploc_rdl(rwl) } {
             abi::E_TMOUT => false,
@@ -55,13 +53,13 @@ impl RwLock {
     }
 
     #[inline]
-    pub unsafe fn write(&self) {
+    pub fn write(&self) {
         let rwl = self.raw();
         expect_success(unsafe { abi::rwl_loc_wrl(rwl) }, &"rwl_loc_wrl");
     }
 
     #[inline]
-    pub unsafe fn try_write(&self) -> bool {
+    pub fn try_write(&self) -> bool {
         let rwl = self.raw();
         match unsafe { abi::rwl_ploc_wrl(rwl) } {
             abi::E_TMOUT => false,
diff --git a/library/std/src/sys/unix/fs.rs b/library/std/src/sys/unix/fs.rs
index e22b2f3340af..37a49f2d78ac 100644
--- a/library/std/src/sys/unix/fs.rs
+++ b/library/std/src/sys/unix/fs.rs
@@ -1,3 +1,6 @@
+// miri has some special hacks here that make things unused.
+#![cfg_attr(miri, allow(unused))]
+
 use crate::os::unix::prelude::*;
 
 use crate::ffi::{CStr, OsStr, OsString};
@@ -850,7 +853,6 @@ impl DirEntry {
         target_os = "fuchsia",
         target_os = "redox"
     )))]
-    #[cfg_attr(miri, allow(unused))]
     fn name_cstr(&self) -> &CStr {
         unsafe { CStr::from_ptr(self.entry.d_name.as_ptr()) }
     }
@@ -862,7 +864,6 @@ impl DirEntry {
         target_os = "fuchsia",
         target_os = "redox"
     ))]
-    #[cfg_attr(miri, allow(unused))]
     fn name_cstr(&self) -> &CStr {
         &self.name
     }
diff --git a/library/std/src/sys/unix/locks/fuchsia_mutex.rs b/library/std/src/sys/unix/locks/fuchsia_mutex.rs
index 117611ce43f2..5d89e5a13fd3 100644
--- a/library/std/src/sys/unix/locks/fuchsia_mutex.rs
+++ b/library/std/src/sys/unix/locks/fuchsia_mutex.rs
@@ -53,8 +53,6 @@ const CONTESTED_BIT: u32 = 1;
 // This can never be a valid `zx_handle_t`.
 const UNLOCKED: u32 = 0;
 
-pub type MovableMutex = Mutex;
-
 pub struct Mutex {
     futex: AtomicU32,
 }
@@ -86,23 +84,27 @@ impl Mutex {
     }
 
     #[inline]
-    pub unsafe fn try_lock(&self) -> bool {
-        let thread_self = zx_thread_self();
+    pub fn try_lock(&self) -> bool {
+        let thread_self = unsafe { zx_thread_self() };
         self.futex.compare_exchange(UNLOCKED, to_state(thread_self), Acquire, Relaxed).is_ok()
     }
 
     #[inline]
-    pub unsafe fn lock(&self) {
-        let thread_self = zx_thread_self();
+    pub fn lock(&self) {
+        let thread_self = unsafe { zx_thread_self() };
         if let Err(state) =
             self.futex.compare_exchange(UNLOCKED, to_state(thread_self), Acquire, Relaxed)
         {
-            self.lock_contested(state, thread_self);
+            unsafe {
+                self.lock_contested(state, thread_self);
+            }
         }
     }
 
+    /// # Safety
+    /// `thread_self` must be the handle for the current thread.
     #[cold]
-    fn lock_contested(&self, mut state: u32, thread_self: zx_handle_t) {
+    unsafe fn lock_contested(&self, mut state: u32, thread_self: zx_handle_t) {
         let owned_state = mark_contested(to_state(thread_self));
         loop {
             // Mark the mutex as contested if it is not already.
diff --git a/library/std/src/sys/unix/locks/futex_condvar.rs b/library/std/src/sys/unix/locks/futex_condvar.rs
index c0576c17880e..4bd65dd25c29 100644
--- a/library/std/src/sys/unix/locks/futex_condvar.rs
+++ b/library/std/src/sys/unix/locks/futex_condvar.rs
@@ -3,8 +3,6 @@ use crate::sync::atomic::{AtomicU32, Ordering::Relaxed};
 use crate::sys::futex::{futex_wait, futex_wake, futex_wake_all};
 use crate::time::Duration;
 
-pub type MovableCondvar = Condvar;
-
 pub struct Condvar {
     // The value of this atomic is simply incremented on every notification.
     // This is used by `.wait()` to not miss any notifications after
@@ -21,12 +19,12 @@ impl Condvar {
     // All the memory orderings here are `Relaxed`,
     // because synchronization is done by unlocking and locking the mutex.
 
-    pub unsafe fn notify_one(&self) {
+    pub fn notify_one(&self) {
         self.futex.fetch_add(1, Relaxed);
         futex_wake(&self.futex);
     }
 
-    pub unsafe fn notify_all(&self) {
+    pub fn notify_all(&self) {
         self.futex.fetch_add(1, Relaxed);
         futex_wake_all(&self.futex);
     }
diff --git a/library/std/src/sys/unix/locks/futex_mutex.rs b/library/std/src/sys/unix/locks/futex_mutex.rs
index 33b13dad4d65..c01229586c30 100644
--- a/library/std/src/sys/unix/locks/futex_mutex.rs
+++ b/library/std/src/sys/unix/locks/futex_mutex.rs
@@ -4,8 +4,6 @@ use crate::sync::atomic::{
 };
 use crate::sys::futex::{futex_wait, futex_wake};
 
-pub type MovableMutex = Mutex;
-
 pub struct Mutex {
     /// 0: unlocked
     /// 1: locked, no other threads waiting
@@ -20,12 +18,12 @@ impl Mutex {
     }
 
     #[inline]
-    pub unsafe fn try_lock(&self) -> bool {
+    pub fn try_lock(&self) -> bool {
         self.futex.compare_exchange(0, 1, Acquire, Relaxed).is_ok()
     }
 
     #[inline]
-    pub unsafe fn lock(&self) {
+    pub fn lock(&self) {
         if self.futex.compare_exchange(0, 1, Acquire, Relaxed).is_err() {
             self.lock_contended();
         }
diff --git a/library/std/src/sys/unix/locks/futex_rwlock.rs b/library/std/src/sys/unix/locks/futex_rwlock.rs
index 0cc92244ecad..aa0de900238f 100644
--- a/library/std/src/sys/unix/locks/futex_rwlock.rs
+++ b/library/std/src/sys/unix/locks/futex_rwlock.rs
@@ -4,8 +4,6 @@ use crate::sync::atomic::{
 };
 use crate::sys::futex::{futex_wait, futex_wake, futex_wake_all};
 
-pub type MovableRwLock = RwLock;
-
 pub struct RwLock {
     // The state consists of a 30-bit reader counter, a 'readers waiting' flag, and a 'writers waiting' flag.
     // Bits 0..30:
@@ -70,14 +68,14 @@ impl RwLock {
     }
 
     #[inline]
-    pub unsafe fn try_read(&self) -> bool {
+    pub fn try_read(&self) -> bool {
         self.state
             .fetch_update(Acquire, Relaxed, |s| is_read_lockable(s).then(|| s + READ_LOCKED))
             .is_ok()
     }
 
     #[inline]
-    pub unsafe fn read(&self) {
+    pub fn read(&self) {
         let state = self.state.load(Relaxed);
         if !is_read_lockable(state)
             || self
@@ -144,14 +142,14 @@ impl RwLock {
     }
 
     #[inline]
-    pub unsafe fn try_write(&self) -> bool {
+    pub fn try_write(&self) -> bool {
         self.state
             .fetch_update(Acquire, Relaxed, |s| is_unlocked(s).then(|| s + WRITE_LOCKED))
             .is_ok()
     }
 
     #[inline]
-    pub unsafe fn write(&self) {
+    pub fn write(&self) {
         if self.state.compare_exchange_weak(0, WRITE_LOCKED, Acquire, Relaxed).is_err() {
             self.write_contended();
         }
diff --git a/library/std/src/sys/unix/locks/mod.rs b/library/std/src/sys/unix/locks/mod.rs
index 9bb314b7010a..b2e0e49ad736 100644
--- a/library/std/src/sys/unix/locks/mod.rs
+++ b/library/std/src/sys/unix/locks/mod.rs
@@ -10,22 +10,22 @@ cfg_if::cfg_if! {
         mod futex_mutex;
         mod futex_rwlock;
         mod futex_condvar;
-        pub(crate) use futex_mutex::{Mutex, MovableMutex};
-        pub(crate) use futex_rwlock::MovableRwLock;
-        pub(crate) use futex_condvar::MovableCondvar;
+        pub(crate) use futex_mutex::Mutex;
+        pub(crate) use futex_rwlock::RwLock;
+        pub(crate) use futex_condvar::Condvar;
     } else if #[cfg(target_os = "fuchsia")] {
         mod fuchsia_mutex;
         mod futex_rwlock;
         mod futex_condvar;
-        pub(crate) use fuchsia_mutex::{Mutex, MovableMutex};
-        pub(crate) use futex_rwlock::MovableRwLock;
-        pub(crate) use futex_condvar::MovableCondvar;
+        pub(crate) use fuchsia_mutex::Mutex;
+        pub(crate) use futex_rwlock::RwLock;
+        pub(crate) use futex_condvar::Condvar;
     } else {
         mod pthread_mutex;
         mod pthread_rwlock;
         mod pthread_condvar;
-        pub(crate) use pthread_mutex::{Mutex, MovableMutex};
-        pub(crate) use pthread_rwlock::MovableRwLock;
-        pub(crate) use pthread_condvar::MovableCondvar;
+        pub(crate) use pthread_mutex::Mutex;
+        pub(crate) use pthread_rwlock::RwLock;
+        pub(crate) use pthread_condvar::Condvar;
     }
 }
diff --git a/library/std/src/sys/unix/locks/pthread_condvar.rs b/library/std/src/sys/unix/locks/pthread_condvar.rs
index 4741c0c6736e..1ddb09905db2 100644
--- a/library/std/src/sys/unix/locks/pthread_condvar.rs
+++ b/library/std/src/sys/unix/locks/pthread_condvar.rs
@@ -1,17 +1,17 @@
 use crate::cell::UnsafeCell;
+use crate::ptr;
+use crate::sync::atomic::{AtomicPtr, Ordering::Relaxed};
 use crate::sys::locks::{pthread_mutex, Mutex};
 use crate::sys_common::lazy_box::{LazyBox, LazyInit};
 use crate::time::Duration;
 
+struct AllocatedCondvar(UnsafeCell<libc::pthread_cond_t>);
+
 pub struct Condvar {
-    inner: UnsafeCell<libc::pthread_cond_t>,
+    inner: LazyBox<AllocatedCondvar>,
+    mutex: AtomicPtr<libc::pthread_mutex_t>,
 }
 
-pub(crate) type MovableCondvar = LazyBox<Condvar>;
-
-unsafe impl Send for Condvar {}
-unsafe impl Sync for Condvar {}
-
 const TIMESPEC_MAX: libc::timespec =
     libc::timespec { tv_sec: <libc::time_t>::MAX, tv_nsec: 1_000_000_000 - 1 };
 
@@ -19,81 +19,104 @@ fn saturating_cast_to_time_t(value: u64) -> libc::time_t {
     if value > <libc::time_t>::MAX as u64 { <libc::time_t>::MAX } else { value as libc::time_t }
 }
 
-impl LazyInit for Condvar {
+#[inline]
+fn raw(c: &Condvar) -> *mut libc::pthread_cond_t {
+    c.inner.0.get()
+}
+
+unsafe impl Send for AllocatedCondvar {}
+unsafe impl Sync for AllocatedCondvar {}
+
+impl LazyInit for AllocatedCondvar {
     fn init() -> Box<Self> {
-        let mut condvar = Box::new(Self::new());
-        unsafe { condvar.init() };
+        let condvar = Box::new(AllocatedCondvar(UnsafeCell::new(libc::PTHREAD_COND_INITIALIZER)));
+
+        cfg_if::cfg_if! {
+            if #[cfg(any(
+                target_os = "macos",
+                target_os = "ios",
+                target_os = "watchos",
+                target_os = "l4re",
+                target_os = "android",
+                target_os = "redox"
+            ))] {
+                // `pthread_condattr_setclock` is unfortunately not supported on these platforms.
+            } else if #[cfg(any(target_os = "espidf", target_os = "horizon"))] {
+                // NOTE: ESP-IDF's PTHREAD_COND_INITIALIZER support is not released yet
+                // So on that platform, init() should always be called
+                // Moreover, that platform does not have pthread_condattr_setclock support,
+                // hence that initialization should be skipped as well
+                //
+                // Similar story for the 3DS (horizon).
+                let r = unsafe { libc::pthread_cond_init(condvar.0.get(), crate::ptr::null()) };
+                assert_eq!(r, 0);
+            } else {
+                use crate::mem::MaybeUninit;
+                let mut attr = MaybeUninit::<libc::pthread_condattr_t>::uninit();
+                let r = unsafe { libc::pthread_condattr_init(attr.as_mut_ptr()) };
+                assert_eq!(r, 0);
+                let r = unsafe { libc::pthread_condattr_setclock(attr.as_mut_ptr(), libc::CLOCK_MONOTONIC) };
+                assert_eq!(r, 0);
+                let r = unsafe { libc::pthread_cond_init(condvar.0.get(), attr.as_ptr()) };
+                assert_eq!(r, 0);
+                let r = unsafe { libc::pthread_condattr_destroy(attr.as_mut_ptr()) };
+                assert_eq!(r, 0);
+            }
+        }
+
         condvar
     }
 }
 
+impl Drop for AllocatedCondvar {
+    #[inline]
+    fn drop(&mut self) {
+        let r = unsafe { libc::pthread_cond_destroy(self.0.get()) };
+        if cfg!(target_os = "dragonfly") {
+            // On DragonFly pthread_cond_destroy() returns EINVAL if called on
+            // a condvar that was just initialized with
+            // libc::PTHREAD_COND_INITIALIZER. Once it is used or
+            // pthread_cond_init() is called, this behaviour no longer occurs.
+            debug_assert!(r == 0 || r == libc::EINVAL);
+        } else {
+            debug_assert_eq!(r, 0);
+        }
+    }
+}
+
 impl Condvar {
     pub const fn new() -> Condvar {
-        // Might be moved and address is changing it is better to avoid
-        // initialization of potentially opaque OS data before it landed
-        Condvar { inner: UnsafeCell::new(libc::PTHREAD_COND_INITIALIZER) }
-    }
-
-    #[cfg(any(
-        target_os = "macos",
-        target_os = "ios",
-        target_os = "watchos",
-        target_os = "l4re",
-        target_os = "android",
-        target_os = "redox"
-    ))]
-    unsafe fn init(&mut self) {}
-
-    // NOTE: ESP-IDF's PTHREAD_COND_INITIALIZER support is not released yet
-    // So on that platform, init() should always be called
-    // Moreover, that platform does not have pthread_condattr_setclock support,
-    // hence that initialization should be skipped as well
-    //
-    // Similar story for the 3DS (horizon).
-    #[cfg(any(target_os = "espidf", target_os = "horizon"))]
-    unsafe fn init(&mut self) {
-        let r = libc::pthread_cond_init(self.inner.get(), crate::ptr::null());
-        assert_eq!(r, 0);
-    }
-
-    #[cfg(not(any(
-        target_os = "macos",
-        target_os = "ios",
-        target_os = "watchos",
-        target_os = "l4re",
-        target_os = "android",
-        target_os = "redox",
-        target_os = "espidf",
-        target_os = "horizon"
-    )))]
-    unsafe fn init(&mut self) {
-        use crate::mem::MaybeUninit;
-        let mut attr = MaybeUninit::<libc::pthread_condattr_t>::uninit();
-        let r = libc::pthread_condattr_init(attr.as_mut_ptr());
-        assert_eq!(r, 0);
-        let r = libc::pthread_condattr_setclock(attr.as_mut_ptr(), libc::CLOCK_MONOTONIC);
-        assert_eq!(r, 0);
-        let r = libc::pthread_cond_init(self.inner.get(), attr.as_ptr());
-        assert_eq!(r, 0);
-        let r = libc::pthread_condattr_destroy(attr.as_mut_ptr());
-        assert_eq!(r, 0);
+        Condvar { inner: LazyBox::new(), mutex: AtomicPtr::new(ptr::null_mut()) }
     }
 
     #[inline]
-    pub unsafe fn notify_one(&self) {
-        let r = libc::pthread_cond_signal(self.inner.get());
+    fn verify(&self, mutex: *mut libc::pthread_mutex_t) {
+        // Relaxed is okay here because we never read through `self.addr`, and only use it to
+        // compare addresses.
+        match self.mutex.compare_exchange(ptr::null_mut(), mutex, Relaxed, Relaxed) {
+            Ok(_) => {}                // Stored the address
+            Err(n) if n == mutex => {} // Lost a race to store the same address
+            _ => panic!("attempted to use a condition variable with two mutexes"),
+        }
+    }
+
+    #[inline]
+    pub fn notify_one(&self) {
+        let r = unsafe { libc::pthread_cond_signal(raw(self)) };
         debug_assert_eq!(r, 0);
     }
 
     #[inline]
-    pub unsafe fn notify_all(&self) {
-        let r = libc::pthread_cond_broadcast(self.inner.get());
+    pub fn notify_all(&self) {
+        let r = unsafe { libc::pthread_cond_broadcast(raw(self)) };
         debug_assert_eq!(r, 0);
     }
 
     #[inline]
     pub unsafe fn wait(&self, mutex: &Mutex) {
-        let r = libc::pthread_cond_wait(self.inner.get(), pthread_mutex::raw(mutex));
+        let mutex = pthread_mutex::raw(mutex);
+        self.verify(mutex);
+        let r = libc::pthread_cond_wait(raw(self), mutex);
         debug_assert_eq!(r, 0);
     }
 
@@ -112,6 +135,9 @@ impl Condvar {
     pub unsafe fn wait_timeout(&self, mutex: &Mutex, dur: Duration) -> bool {
         use crate::mem;
 
+        let mutex = pthread_mutex::raw(mutex);
+        self.verify(mutex);
+
         let mut now: libc::timespec = mem::zeroed();
         let r = libc::clock_gettime(libc::CLOCK_MONOTONIC, &mut now);
         assert_eq!(r, 0);
@@ -127,7 +153,7 @@ impl Condvar {
         let timeout =
             sec.map(|s| libc::timespec { tv_sec: s, tv_nsec: nsec as _ }).unwrap_or(TIMESPEC_MAX);
 
-        let r = libc::pthread_cond_timedwait(self.inner.get(), pthread_mutex::raw(mutex), &timeout);
+        let r = libc::pthread_cond_timedwait(raw(self), mutex, &timeout);
         assert!(r == libc::ETIMEDOUT || r == 0);
         r == 0
     }
@@ -144,9 +170,11 @@ impl Condvar {
         target_os = "horizon"
     ))]
     pub unsafe fn wait_timeout(&self, mutex: &Mutex, mut dur: Duration) -> bool {
-        use crate::ptr;
         use crate::time::Instant;
 
+        let mutex = pthread_mutex::raw(mutex);
+        self.verify(mutex);
+
         // 1000 years
         let max_dur = Duration::from_secs(1000 * 365 * 86400);
 
@@ -187,36 +215,11 @@ impl Condvar {
             .unwrap_or(TIMESPEC_MAX);
 
         // And wait!
-        let r = libc::pthread_cond_timedwait(self.inner.get(), pthread_mutex::raw(mutex), &timeout);
+        let r = libc::pthread_cond_timedwait(raw(self), mutex, &timeout);
         debug_assert!(r == libc::ETIMEDOUT || r == 0);
 
         // ETIMEDOUT is not a totally reliable method of determining timeout due
         // to clock shifts, so do the check ourselves
         stable_now.elapsed() < dur
     }
-
-    #[inline]
-    #[cfg(not(target_os = "dragonfly"))]
-    unsafe fn destroy(&mut self) {
-        let r = libc::pthread_cond_destroy(self.inner.get());
-        debug_assert_eq!(r, 0);
-    }
-
-    #[inline]
-    #[cfg(target_os = "dragonfly")]
-    unsafe fn destroy(&mut self) {
-        let r = libc::pthread_cond_destroy(self.inner.get());
-        // On DragonFly pthread_cond_destroy() returns EINVAL if called on
-        // a condvar that was just initialized with
-        // libc::PTHREAD_COND_INITIALIZER. Once it is used or
-        // pthread_cond_init() is called, this behaviour no longer occurs.
-        debug_assert!(r == 0 || r == libc::EINVAL);
-    }
-}
-
-impl Drop for Condvar {
-    #[inline]
-    fn drop(&mut self) {
-        unsafe { self.destroy() };
-    }
 }
diff --git a/library/std/src/sys/unix/locks/pthread_mutex.rs b/library/std/src/sys/unix/locks/pthread_mutex.rs
index 5964935ddb54..8a78bc1fd739 100644
--- a/library/std/src/sys/unix/locks/pthread_mutex.rs
+++ b/library/std/src/sys/unix/locks/pthread_mutex.rs
@@ -3,56 +3,24 @@ use crate::mem::{forget, MaybeUninit};
 use crate::sys::cvt_nz;
 use crate::sys_common::lazy_box::{LazyBox, LazyInit};
 
-pub struct Mutex {
-    inner: UnsafeCell<libc::pthread_mutex_t>,
-}
+struct AllocatedMutex(UnsafeCell<libc::pthread_mutex_t>);
 
-pub(crate) type MovableMutex = LazyBox<Mutex>;
+pub struct Mutex {
+    inner: LazyBox<AllocatedMutex>,
+}
 
 #[inline]
 pub unsafe fn raw(m: &Mutex) -> *mut libc::pthread_mutex_t {
-    m.inner.get()
+    m.inner.0.get()
 }
 
-unsafe impl Send for Mutex {}
-unsafe impl Sync for Mutex {}
+unsafe impl Send for AllocatedMutex {}
+unsafe impl Sync for AllocatedMutex {}
 
-impl LazyInit for Mutex {
+impl LazyInit for AllocatedMutex {
     fn init() -> Box<Self> {
-        let mut mutex = Box::new(Self::new());
-        unsafe { mutex.init() };
-        mutex
-    }
+        let mutex = Box::new(AllocatedMutex(UnsafeCell::new(libc::PTHREAD_MUTEX_INITIALIZER)));
 
-    fn destroy(mutex: Box<Self>) {
-        // We're not allowed to pthread_mutex_destroy a locked mutex,
-        // so check first if it's unlocked.
-        if unsafe { mutex.try_lock() } {
-            unsafe { mutex.unlock() };
-            drop(mutex);
-        } else {
-            // The mutex is locked. This happens if a MutexGuard is leaked.
-            // In this case, we just leak the Mutex too.
-            forget(mutex);
-        }
-    }
-
-    fn cancel_init(_: Box<Self>) {
-        // In this case, we can just drop it without any checks,
-        // since it cannot have been locked yet.
-    }
-}
-
-impl Mutex {
-    pub const fn new() -> Mutex {
-        // Might be moved to a different address, so it is better to avoid
-        // initialization of potentially opaque OS data before it landed.
-        // Be very careful using this newly constructed `Mutex`, reentrant
-        // locking is undefined behavior until `init` is called!
-        Mutex { inner: UnsafeCell::new(libc::PTHREAD_MUTEX_INITIALIZER) }
-    }
-    #[inline]
-    unsafe fn init(&mut self) {
         // Issue #33770
         //
         // A pthread mutex initialized with PTHREAD_MUTEX_INITIALIZER will have
@@ -77,49 +45,77 @@ impl Mutex {
         // references, we instead create the mutex with type
         // PTHREAD_MUTEX_NORMAL which is guaranteed to deadlock if we try to
         // re-lock it from the same thread, thus avoiding undefined behavior.
-        let mut attr = MaybeUninit::<libc::pthread_mutexattr_t>::uninit();
-        cvt_nz(libc::pthread_mutexattr_init(attr.as_mut_ptr())).unwrap();
-        let attr = PthreadMutexAttr(&mut attr);
-        cvt_nz(libc::pthread_mutexattr_settype(attr.0.as_mut_ptr(), libc::PTHREAD_MUTEX_NORMAL))
+        unsafe {
+            let mut attr = MaybeUninit::<libc::pthread_mutexattr_t>::uninit();
+            cvt_nz(libc::pthread_mutexattr_init(attr.as_mut_ptr())).unwrap();
+            let attr = PthreadMutexAttr(&mut attr);
+            cvt_nz(libc::pthread_mutexattr_settype(
+                attr.0.as_mut_ptr(),
+                libc::PTHREAD_MUTEX_NORMAL,
+            ))
             .unwrap();
-        cvt_nz(libc::pthread_mutex_init(self.inner.get(), attr.0.as_ptr())).unwrap();
+            cvt_nz(libc::pthread_mutex_init(mutex.0.get(), attr.0.as_ptr())).unwrap();
+        }
+
+        mutex
     }
-    #[inline]
-    pub unsafe fn lock(&self) {
-        let r = libc::pthread_mutex_lock(self.inner.get());
-        debug_assert_eq!(r, 0);
+
+    fn destroy(mutex: Box<Self>) {
+        // We're not allowed to pthread_mutex_destroy a locked mutex,
+        // so check first if it's unlocked.
+        if unsafe { libc::pthread_mutex_trylock(mutex.0.get()) == 0 } {
+            unsafe { libc::pthread_mutex_unlock(mutex.0.get()) };
+            drop(mutex);
+        } else {
+            // The mutex is locked. This happens if a MutexGuard is leaked.
+            // In this case, we just leak the Mutex too.
+            forget(mutex);
+        }
     }
-    #[inline]
-    pub unsafe fn unlock(&self) {
-        let r = libc::pthread_mutex_unlock(self.inner.get());
-        debug_assert_eq!(r, 0);
-    }
-    #[inline]
-    pub unsafe fn try_lock(&self) -> bool {
-        libc::pthread_mutex_trylock(self.inner.get()) == 0
-    }
-    #[inline]
-    #[cfg(not(target_os = "dragonfly"))]
-    unsafe fn destroy(&mut self) {
-        let r = libc::pthread_mutex_destroy(self.inner.get());
-        debug_assert_eq!(r, 0);
-    }
-    #[inline]
-    #[cfg(target_os = "dragonfly")]
-    unsafe fn destroy(&mut self) {
-        let r = libc::pthread_mutex_destroy(self.inner.get());
-        // On DragonFly pthread_mutex_destroy() returns EINVAL if called on a
-        // mutex that was just initialized with libc::PTHREAD_MUTEX_INITIALIZER.
-        // Once it is used (locked/unlocked) or pthread_mutex_init() is called,
-        // this behaviour no longer occurs.
-        debug_assert!(r == 0 || r == libc::EINVAL);
+
+    fn cancel_init(_: Box<Self>) {
+        // In this case, we can just drop it without any checks,
+        // since it cannot have been locked yet.
     }
 }
 
-impl Drop for Mutex {
+impl Drop for AllocatedMutex {
     #[inline]
     fn drop(&mut self) {
-        unsafe { self.destroy() };
+        let r = unsafe { libc::pthread_mutex_destroy(self.0.get()) };
+        if cfg!(target_os = "dragonfly") {
+            // On DragonFly pthread_mutex_destroy() returns EINVAL if called on a
+            // mutex that was just initialized with libc::PTHREAD_MUTEX_INITIALIZER.
+            // Once it is used (locked/unlocked) or pthread_mutex_init() is called,
+            // this behaviour no longer occurs.
+            debug_assert!(r == 0 || r == libc::EINVAL);
+        } else {
+            debug_assert_eq!(r, 0);
+        }
+    }
+}
+
+impl Mutex {
+    #[inline]
+    pub const fn new() -> Mutex {
+        Mutex { inner: LazyBox::new() }
+    }
+
+    #[inline]
+    pub unsafe fn lock(&self) {
+        let r = libc::pthread_mutex_lock(raw(self));
+        debug_assert_eq!(r, 0);
+    }
+
+    #[inline]
+    pub unsafe fn unlock(&self) {
+        let r = libc::pthread_mutex_unlock(raw(self));
+        debug_assert_eq!(r, 0);
+    }
+
+    #[inline]
+    pub unsafe fn try_lock(&self) -> bool {
+        libc::pthread_mutex_trylock(raw(self)) == 0
     }
 }
 
diff --git a/library/std/src/sys/unix/locks/pthread_rwlock.rs b/library/std/src/sys/unix/locks/pthread_rwlock.rs
index adfe2a88338f..04662be9d827 100644
--- a/library/std/src/sys/unix/locks/pthread_rwlock.rs
+++ b/library/std/src/sys/unix/locks/pthread_rwlock.rs
@@ -3,20 +3,26 @@ use crate::mem::forget;
 use crate::sync::atomic::{AtomicUsize, Ordering};
 use crate::sys_common::lazy_box::{LazyBox, LazyInit};
 
-pub struct RwLock {
+struct AllocatedRwLock {
     inner: UnsafeCell<libc::pthread_rwlock_t>,
     write_locked: UnsafeCell<bool>, // guarded by the `inner` RwLock
     num_readers: AtomicUsize,
 }
 
-pub(crate) type MovableRwLock = LazyBox<RwLock>;
+unsafe impl Send for AllocatedRwLock {}
+unsafe impl Sync for AllocatedRwLock {}
 
-unsafe impl Send for RwLock {}
-unsafe impl Sync for RwLock {}
+pub struct RwLock {
+    inner: LazyBox<AllocatedRwLock>,
+}
 
-impl LazyInit for RwLock {
+impl LazyInit for AllocatedRwLock {
     fn init() -> Box<Self> {
-        Box::new(Self::new())
+        Box::new(AllocatedRwLock {
+            inner: UnsafeCell::new(libc::PTHREAD_RWLOCK_INITIALIZER),
+            write_locked: UnsafeCell::new(false),
+            num_readers: AtomicUsize::new(0),
+        })
     }
 
     fn destroy(mut rwlock: Box<Self>) {
@@ -35,17 +41,39 @@ impl LazyInit for RwLock {
     }
 }
 
-impl RwLock {
-    pub const fn new() -> RwLock {
-        RwLock {
-            inner: UnsafeCell::new(libc::PTHREAD_RWLOCK_INITIALIZER),
-            write_locked: UnsafeCell::new(false),
-            num_readers: AtomicUsize::new(0),
+impl AllocatedRwLock {
+    #[inline]
+    unsafe fn raw_unlock(&self) {
+        let r = libc::pthread_rwlock_unlock(self.inner.get());
+        debug_assert_eq!(r, 0);
+    }
+}
+
+impl Drop for AllocatedRwLock {
+    fn drop(&mut self) {
+        let r = unsafe { libc::pthread_rwlock_destroy(self.inner.get()) };
+        // On DragonFly pthread_rwlock_destroy() returns EINVAL if called on a
+        // rwlock that was just initialized with
+        // libc::PTHREAD_RWLOCK_INITIALIZER. Once it is used (locked/unlocked)
+        // or pthread_rwlock_init() is called, this behaviour no longer occurs.
+        if cfg!(target_os = "dragonfly") {
+            debug_assert!(r == 0 || r == libc::EINVAL);
+        } else {
+            debug_assert_eq!(r, 0);
         }
     }
+}
+
+impl RwLock {
     #[inline]
-    pub unsafe fn read(&self) {
-        let r = libc::pthread_rwlock_rdlock(self.inner.get());
+    pub const fn new() -> RwLock {
+        RwLock { inner: LazyBox::new() }
+    }
+
+    #[inline]
+    pub fn read(&self) {
+        let lock = &*self.inner;
+        let r = unsafe { libc::pthread_rwlock_rdlock(lock.inner.get()) };
 
         // According to POSIX, when a thread tries to acquire this read lock
         // while it already holds the write lock
@@ -62,51 +90,61 @@ impl RwLock {
         // got the write lock more than once, or got a read and a write lock.
         if r == libc::EAGAIN {
             panic!("rwlock maximum reader count exceeded");
-        } else if r == libc::EDEADLK || (r == 0 && *self.write_locked.get()) {
+        } else if r == libc::EDEADLK || (r == 0 && unsafe { *lock.write_locked.get() }) {
             // Above, we make sure to only access `write_locked` when `r == 0` to avoid
             // data races.
             if r == 0 {
                 // `pthread_rwlock_rdlock` succeeded when it should not have.
-                self.raw_unlock();
+                unsafe {
+                    lock.raw_unlock();
+                }
             }
             panic!("rwlock read lock would result in deadlock");
         } else {
             // POSIX does not make guarantees about all the errors that may be returned.
             // See issue #94705 for more details.
             assert_eq!(r, 0, "unexpected error during rwlock read lock: {:?}", r);
-            self.num_readers.fetch_add(1, Ordering::Relaxed);
+            lock.num_readers.fetch_add(1, Ordering::Relaxed);
         }
     }
+
     #[inline]
-    pub unsafe fn try_read(&self) -> bool {
-        let r = libc::pthread_rwlock_tryrdlock(self.inner.get());
+    pub fn try_read(&self) -> bool {
+        let lock = &*self.inner;
+        let r = unsafe { libc::pthread_rwlock_tryrdlock(lock.inner.get()) };
         if r == 0 {
-            if *self.write_locked.get() {
+            if unsafe { *lock.write_locked.get() } {
                 // `pthread_rwlock_tryrdlock` succeeded when it should not have.
-                self.raw_unlock();
+                unsafe {
+                    lock.raw_unlock();
+                }
                 false
             } else {
-                self.num_readers.fetch_add(1, Ordering::Relaxed);
+                lock.num_readers.fetch_add(1, Ordering::Relaxed);
                 true
             }
         } else {
             false
         }
     }
+
     #[inline]
-    pub unsafe fn write(&self) {
-        let r = libc::pthread_rwlock_wrlock(self.inner.get());
+    pub fn write(&self) {
+        let lock = &*self.inner;
+        let r = unsafe { libc::pthread_rwlock_wrlock(lock.inner.get()) };
         // See comments above for why we check for EDEADLK and write_locked. For the same reason,
         // we also need to check that there are no readers (tracked in `num_readers`).
         if r == libc::EDEADLK
-            || (r == 0 && *self.write_locked.get())
-            || self.num_readers.load(Ordering::Relaxed) != 0
+            || (r == 0 && unsafe { *lock.write_locked.get() })
+            || lock.num_readers.load(Ordering::Relaxed) != 0
         {
             // Above, we make sure to only access `write_locked` when `r == 0` to avoid
             // data races.
             if r == 0 {
                 // `pthread_rwlock_wrlock` succeeded when it should not have.
-                self.raw_unlock();
+                unsafe {
+                    lock.raw_unlock();
+                }
             }
             panic!("rwlock write lock would result in deadlock");
         } else {
@@ -114,60 +152,44 @@ impl RwLock {
             // return EDEADLK or 0. We rely on that.
             debug_assert_eq!(r, 0);
         }
-        *self.write_locked.get() = true;
+
+        unsafe {
+            *lock.write_locked.get() = true;
+        }
     }
+
     #[inline]
     pub unsafe fn try_write(&self) -> bool {
-        let r = libc::pthread_rwlock_trywrlock(self.inner.get());
+        let lock = &*self.inner;
+        let r = libc::pthread_rwlock_trywrlock(lock.inner.get());
         if r == 0 {
-            if *self.write_locked.get() || self.num_readers.load(Ordering::Relaxed) != 0 {
+            if *lock.write_locked.get() || lock.num_readers.load(Ordering::Relaxed) != 0 {
                 // `pthread_rwlock_trywrlock` succeeded when it should not have.
-                self.raw_unlock();
+                lock.raw_unlock();
                 false
             } else {
-                *self.write_locked.get() = true;
+                *lock.write_locked.get() = true;
                 true
             }
         } else {
             false
         }
     }
-    #[inline]
-    unsafe fn raw_unlock(&self) {
-        let r = libc::pthread_rwlock_unlock(self.inner.get());
-        debug_assert_eq!(r, 0);
-    }
+
     #[inline]
     pub unsafe fn read_unlock(&self) {
-        debug_assert!(!*self.write_locked.get());
-        self.num_readers.fetch_sub(1, Ordering::Relaxed);
-        self.raw_unlock();
+        let lock = &*self.inner;
+        debug_assert!(!*lock.write_locked.get());
+        lock.num_readers.fetch_sub(1, Ordering::Relaxed);
+        lock.raw_unlock();
     }
+
     #[inline]
     pub unsafe fn write_unlock(&self) {
-        debug_assert_eq!(self.num_readers.load(Ordering::Relaxed), 0);
-        debug_assert!(*self.write_locked.get());
-        *self.write_locked.get() = false;
-        self.raw_unlock();
-    }
-    #[inline]
-    unsafe fn destroy(&mut self) {
-        let r = libc::pthread_rwlock_destroy(self.inner.get());
-        // On DragonFly pthread_rwlock_destroy() returns EINVAL if called on a
-        // rwlock that was just initialized with
-        // libc::PTHREAD_RWLOCK_INITIALIZER. Once it is used (locked/unlocked)
-        // or pthread_rwlock_init() is called, this behaviour no longer occurs.
-        if cfg!(target_os = "dragonfly") {
-            debug_assert!(r == 0 || r == libc::EINVAL);
-        } else {
-            debug_assert_eq!(r, 0);
-        }
-    }
-}
-
-impl Drop for RwLock {
-    #[inline]
-    fn drop(&mut self) {
-        unsafe { self.destroy() };
+        let lock = &*self.inner;
+        debug_assert_eq!(lock.num_readers.load(Ordering::Relaxed), 0);
+        debug_assert!(*lock.write_locked.get());
+        *lock.write_locked.get() = false;
+        lock.raw_unlock();
     }
 }
diff --git a/library/std/src/sys/unix/thread.rs b/library/std/src/sys/unix/thread.rs
index 42ac6fcd8bf3..c1d30dd9d521 100644
--- a/library/std/src/sys/unix/thread.rs
+++ b/library/std/src/sys/unix/thread.rs
@@ -132,9 +132,14 @@ impl Thread {
 
     #[cfg(target_os = "linux")]
     pub fn set_name(name: &CStr) {
+        const TASK_COMM_LEN: usize = 16;
+
         unsafe {
             // Available since glibc 2.12, musl 1.1.16, and uClibc 1.0.20.
-            libc::pthread_setname_np(libc::pthread_self(), name.as_ptr());
+            let name = truncate_cstr(name, TASK_COMM_LEN);
+            let res = libc::pthread_setname_np(libc::pthread_self(), name.as_ptr());
+            // We have no good way of propagating errors here, but in debug-builds let's check that this actually worked.
+            debug_assert_eq!(res, 0);
         }
     }
 
@@ -148,7 +153,10 @@ impl Thread {
     #[cfg(any(target_os = "macos", target_os = "ios", target_os = "watchos"))]
     pub fn set_name(name: &CStr) {
         unsafe {
-            libc::pthread_setname_np(name.as_ptr());
+            let name = truncate_cstr(name, libc::MAXTHREADNAMESIZE);
+            let res = libc::pthread_setname_np(name.as_ptr());
+            // We have no good way of propagating errors here, but in debug-builds let's check that this actually worked.
+            debug_assert_eq!(res, 0);
         }
     }
 
@@ -156,11 +164,12 @@ impl Thread {
     pub fn set_name(name: &CStr) {
         unsafe {
             let cname = CStr::from_bytes_with_nul_unchecked(b"%s\0".as_slice());
-            libc::pthread_setname_np(
+            let res = libc::pthread_setname_np(
                 libc::pthread_self(),
                 cname.as_ptr(),
                 name.as_ptr() as *mut libc::c_void,
             );
+            debug_assert_eq!(res, 0);
         }
     }
 
@@ -173,9 +182,8 @@ impl Thread {
         }
 
         if let Some(f) = pthread_setname_np.get() {
-            unsafe {
-                f(libc::pthread_self(), name.as_ptr());
-            }
+            let res = unsafe { f(libc::pthread_self(), name.as_ptr()) };
+            debug_assert_eq!(res, 0);
         }
     }
 
@@ -276,6 +284,20 @@ impl Drop for Thread {
     }
 }
 
+#[cfg(any(target_os = "linux", target_os = "macos", target_os = "ios", target_os = "watchos"))]
+fn truncate_cstr(cstr: &CStr, max_with_nul: usize) -> crate::borrow::Cow<'_, CStr> {
+    use crate::{borrow::Cow, ffi::CString};
+
+    if cstr.to_bytes_with_nul().len() > max_with_nul {
+        let bytes = cstr.to_bytes()[..max_with_nul - 1].to_vec();
+        // SAFETY: the non-nul bytes came straight from a CStr.
+        // (CString will add the terminating nul.)
+        Cow::Owned(unsafe { CString::from_vec_unchecked(bytes) })
+    } else {
+        Cow::Borrowed(cstr)
+    }
+}
+
 pub fn available_parallelism() -> io::Result<NonZeroUsize> {
     cfg_if::cfg_if! {
         if #[cfg(any(
diff --git a/library/std/src/sys/unsupported/locks/condvar.rs b/library/std/src/sys/unsupported/locks/condvar.rs
index 527a26a12bce..3f0943b50ee4 100644
--- a/library/std/src/sys/unsupported/locks/condvar.rs
+++ b/library/std/src/sys/unsupported/locks/condvar.rs
@@ -3,8 +3,6 @@ use crate::time::Duration;
 
 pub struct Condvar {}
 
-pub type MovableCondvar = Condvar;
-
 impl Condvar {
     #[inline]
     #[rustc_const_stable(feature = "const_locks", since = "1.63.0")]
@@ -13,10 +11,10 @@ impl Condvar {
     }
 
     #[inline]
-    pub unsafe fn notify_one(&self) {}
+    pub fn notify_one(&self) {}
 
     #[inline]
-    pub unsafe fn notify_all(&self) {}
+    pub fn notify_all(&self) {}
 
     pub unsafe fn wait(&self, _mutex: &Mutex) {
         panic!("condvar wait not supported")
diff --git a/library/std/src/sys/unsupported/locks/mod.rs b/library/std/src/sys/unsupported/locks/mod.rs
index 602a2d6231a2..0e0f9eccb213 100644
--- a/library/std/src/sys/unsupported/locks/mod.rs
+++ b/library/std/src/sys/unsupported/locks/mod.rs
@@ -1,6 +1,6 @@
 mod condvar;
 mod mutex;
 mod rwlock;
-pub use condvar::{Condvar, MovableCondvar};
-pub use mutex::{MovableMutex, Mutex};
-pub use rwlock::MovableRwLock;
+pub use condvar::Condvar;
+pub use mutex::Mutex;
+pub use rwlock::RwLock;
diff --git a/library/std/src/sys/unsupported/locks/mutex.rs b/library/std/src/sys/unsupported/locks/mutex.rs
index 87ea475c6e3e..4a13c55fb8be 100644
--- a/library/std/src/sys/unsupported/locks/mutex.rs
+++ b/library/std/src/sys/unsupported/locks/mutex.rs
@@ -5,8 +5,6 @@ pub struct Mutex {
     locked: Cell<bool>,
 }
 
-pub type MovableMutex = Mutex;
-
 unsafe impl Send for Mutex {}
 unsafe impl Sync for Mutex {} // no threads on this platform
 
@@ -18,7 +16,7 @@ impl Mutex {
     }
 
     #[inline]
-    pub unsafe fn lock(&self) {
+    pub fn lock(&self) {
         assert_eq!(self.locked.replace(true), false, "cannot recursively acquire mutex");
     }
 
@@ -28,7 +26,7 @@ impl Mutex {
     }
 
     #[inline]
-    pub unsafe fn try_lock(&self) -> bool {
+    pub fn try_lock(&self) -> bool {
         self.locked.replace(true) == false
     }
 }
diff --git a/library/std/src/sys/unsupported/locks/rwlock.rs b/library/std/src/sys/unsupported/locks/rwlock.rs
index 5292691b9555..789ef9b29e52 100644
--- a/library/std/src/sys/unsupported/locks/rwlock.rs
+++ b/library/std/src/sys/unsupported/locks/rwlock.rs
@@ -5,8 +5,6 @@ pub struct RwLock {
     mode: Cell<isize>,
 }
 
-pub type MovableRwLock = RwLock;
-
 unsafe impl Send for RwLock {}
 unsafe impl Sync for RwLock {} // no threads on this platform
 
@@ -18,7 +16,7 @@ impl RwLock {
     }
 
     #[inline]
-    pub unsafe fn read(&self) {
+    pub fn read(&self) {
         let m = self.mode.get();
         if m >= 0 {
             self.mode.set(m + 1);
@@ -28,7 +26,7 @@ impl RwLock {
     }
 
     #[inline]
-    pub unsafe fn try_read(&self) -> bool {
+    pub fn try_read(&self) -> bool {
         let m = self.mode.get();
         if m >= 0 {
             self.mode.set(m + 1);
@@ -39,14 +37,14 @@ impl RwLock {
     }
 
     #[inline]
-    pub unsafe fn write(&self) {
+    pub fn write(&self) {
         if self.mode.replace(-1) != 0 {
             rtabort!("rwlock locked for reading")
         }
     }
 
     #[inline]
-    pub unsafe fn try_write(&self) -> bool {
+    pub fn try_write(&self) -> bool {
         if self.mode.get() == 0 {
             self.mode.set(-1);
             true
diff --git a/library/std/src/sys/wasm/mod.rs b/library/std/src/sys/wasm/mod.rs
index 93838390bee6..d68c3e5f1dfb 100644
--- a/library/std/src/sys/wasm/mod.rs
+++ b/library/std/src/sys/wasm/mod.rs
@@ -55,9 +55,9 @@ cfg_if::cfg_if! {
             mod futex_condvar;
             mod futex_mutex;
             mod futex_rwlock;
-            pub(crate) use futex_condvar::{Condvar, MovableCondvar};
-            pub(crate) use futex_mutex::{Mutex, MovableMutex};
-            pub(crate) use futex_rwlock::MovableRwLock;
+            pub(crate) use futex_condvar::Condvar;
+            pub(crate) use futex_mutex::Mutex;
+            pub(crate) use futex_rwlock::RwLock;
         }
         #[path = "atomics/futex.rs"]
         pub mod futex;
diff --git a/library/std/src/sys/windows/c.rs b/library/std/src/sys/windows/c.rs
index be6fc2ebb7a2..81461de4f721 100644
--- a/library/std/src/sys/windows/c.rs
+++ b/library/std/src/sys/windows/c.rs
@@ -56,6 +56,7 @@ pub type LPPROCESS_INFORMATION = *mut PROCESS_INFORMATION;
 pub type LPSECURITY_ATTRIBUTES = *mut SECURITY_ATTRIBUTES;
 pub type LPSTARTUPINFO = *mut STARTUPINFO;
 pub type LPVOID = *mut c_void;
+pub type LPCVOID = *const c_void;
 pub type LPWCH = *mut WCHAR;
 pub type LPWIN32_FIND_DATAW = *mut WIN32_FIND_DATAW;
 pub type LPWSADATA = *mut WSADATA;
@@ -362,7 +363,7 @@ impl IO_STATUS_BLOCK {
 
 pub type LPOVERLAPPED_COMPLETION_ROUTINE = unsafe extern "system" fn(
     dwErrorCode: DWORD,
-    dwNumberOfBytesTransfered: DWORD,
+    dwNumberOfBytesTransferred: DWORD,
     lpOverlapped: *mut OVERLAPPED,
 );
 
@@ -773,6 +774,16 @@ pub struct timeval {
     pub tv_usec: c_long,
 }
 
+#[repr(C)]
+#[derive(Copy, Clone)]
+pub struct CONSOLE_READCONSOLE_CONTROL {
+    pub nLength: ULONG,
+    pub nInitialChars: ULONG,
+    pub dwCtrlWakeupMask: ULONG,
+    pub dwControlKeyState: ULONG,
+}
+pub type PCONSOLE_READCONSOLE_CONTROL = *mut CONSOLE_READCONSOLE_CONTROL;
+
 // Desktop specific functions & types
 cfg_if::cfg_if! {
 if #[cfg(not(target_vendor = "uwp"))] {
@@ -801,17 +812,6 @@ if #[cfg(not(target_vendor = "uwp"))] {
     pub type PVECTORED_EXCEPTION_HANDLER =
         extern "system" fn(ExceptionInfo: *mut EXCEPTION_POINTERS) -> LONG;
 
-    #[repr(C)]
-    #[derive(Copy, Clone)]
-    pub struct CONSOLE_READCONSOLE_CONTROL {
-        pub nLength: ULONG,
-        pub nInitialChars: ULONG,
-        pub dwCtrlWakeupMask: ULONG,
-        pub dwControlKeyState: ULONG,
-    }
-
-    pub type PCONSOLE_READCONSOLE_CONTROL = *mut CONSOLE_READCONSOLE_CONTROL;
-
     #[repr(C)]
     pub struct BY_HANDLE_FILE_INFORMATION {
         pub dwFileAttributes: DWORD,
@@ -827,7 +827,6 @@ if #[cfg(not(target_vendor = "uwp"))] {
     }
 
     pub type LPBY_HANDLE_FILE_INFORMATION = *mut BY_HANDLE_FILE_INFORMATION;
-    pub type LPCVOID = *const c_void;
 
     pub const HANDLE_FLAG_INHERIT: DWORD = 0x00000001;
 
@@ -855,24 +854,6 @@ if #[cfg(not(target_vendor = "uwp"))] {
 
     #[link(name = "kernel32")]
     extern "system" {
-        // Functions forbidden when targeting UWP
-        pub fn ReadConsoleW(
-            hConsoleInput: HANDLE,
-            lpBuffer: LPVOID,
-            nNumberOfCharsToRead: DWORD,
-            lpNumberOfCharsRead: LPDWORD,
-            pInputControl: PCONSOLE_READCONSOLE_CONTROL,
-        ) -> BOOL;
-
-        pub fn WriteConsoleW(
-            hConsoleOutput: HANDLE,
-            lpBuffer: LPCVOID,
-            nNumberOfCharsToWrite: DWORD,
-            lpNumberOfCharsWritten: LPDWORD,
-            lpReserved: LPVOID,
-        ) -> BOOL;
-
-        pub fn GetConsoleMode(hConsoleHandle: HANDLE, lpMode: LPDWORD) -> BOOL;
         // Allowed but unused by UWP
         pub fn GetFileInformationByHandle(
             hFile: HANDLE,
@@ -914,6 +895,22 @@ if #[cfg(target_vendor = "uwp")] {
 extern "system" {
     pub fn GetCurrentProcessId() -> DWORD;
 
+    pub fn ReadConsoleW(
+        hConsoleInput: HANDLE,
+        lpBuffer: LPVOID,
+        nNumberOfCharsToRead: DWORD,
+        lpNumberOfCharsRead: LPDWORD,
+        pInputControl: PCONSOLE_READCONSOLE_CONTROL,
+    ) -> BOOL;
+    pub fn WriteConsoleW(
+        hConsoleOutput: HANDLE,
+        lpBuffer: LPCVOID,
+        nNumberOfCharsToWrite: DWORD,
+        lpNumberOfCharsWritten: LPDWORD,
+        lpReserved: LPVOID,
+    ) -> BOOL;
+    pub fn GetConsoleMode(hConsoleHandle: HANDLE, lpMode: LPDWORD) -> BOOL;
+
     pub fn GetSystemDirectoryW(lpBuffer: LPWSTR, uSize: UINT) -> UINT;
     pub fn RemoveDirectoryW(lpPathName: LPCWSTR) -> BOOL;
     pub fn SetFileAttributesW(lpFileName: LPCWSTR, dwFileAttributes: DWORD) -> BOOL;
diff --git a/library/std/src/sys/windows/locks/condvar.rs b/library/std/src/sys/windows/locks/condvar.rs
index be9a2abbe35d..66fafa2c00b0 100644
--- a/library/std/src/sys/windows/locks/condvar.rs
+++ b/library/std/src/sys/windows/locks/condvar.rs
@@ -8,8 +8,6 @@ pub struct Condvar {
     inner: UnsafeCell<c::CONDITION_VARIABLE>,
 }
 
-pub type MovableCondvar = Condvar;
-
 unsafe impl Send for Condvar {}
 unsafe impl Sync for Condvar {}
 
@@ -41,12 +39,12 @@ impl Condvar {
     }
 
     #[inline]
-    pub unsafe fn notify_one(&self) {
-        c::WakeConditionVariable(self.inner.get())
+    pub fn notify_one(&self) {
+        unsafe { c::WakeConditionVariable(self.inner.get()) }
     }
 
     #[inline]
-    pub unsafe fn notify_all(&self) {
-        c::WakeAllConditionVariable(self.inner.get())
+    pub fn notify_all(&self) {
+        unsafe { c::WakeAllConditionVariable(self.inner.get()) }
     }
 }
diff --git a/library/std/src/sys/windows/locks/mod.rs b/library/std/src/sys/windows/locks/mod.rs
index 602a2d6231a2..0e0f9eccb213 100644
--- a/library/std/src/sys/windows/locks/mod.rs
+++ b/library/std/src/sys/windows/locks/mod.rs
@@ -1,6 +1,6 @@
 mod condvar;
 mod mutex;
 mod rwlock;
-pub use condvar::{Condvar, MovableCondvar};
-pub use mutex::{MovableMutex, Mutex};
-pub use rwlock::MovableRwLock;
+pub use condvar::Condvar;
+pub use mutex::Mutex;
+pub use rwlock::RwLock;
diff --git a/library/std/src/sys/windows/locks/mutex.rs b/library/std/src/sys/windows/locks/mutex.rs
index 91207f5f4665..ef2f84082cd5 100644
--- a/library/std/src/sys/windows/locks/mutex.rs
+++ b/library/std/src/sys/windows/locks/mutex.rs
@@ -21,9 +21,6 @@ pub struct Mutex {
     srwlock: UnsafeCell<c::SRWLOCK>,
 }
 
-// Windows SRW Locks are movable (while not borrowed).
-pub type MovableMutex = Mutex;
-
 unsafe impl Send for Mutex {}
 unsafe impl Sync for Mutex {}
 
@@ -39,13 +36,15 @@ impl Mutex {
     }
 
     #[inline]
-    pub unsafe fn lock(&self) {
-        c::AcquireSRWLockExclusive(raw(self));
+    pub fn lock(&self) {
+        unsafe {
+            c::AcquireSRWLockExclusive(raw(self));
+        }
     }
 
     #[inline]
-    pub unsafe fn try_lock(&self) -> bool {
-        c::TryAcquireSRWLockExclusive(raw(self)) != 0
+    pub fn try_lock(&self) -> bool {
+        unsafe { c::TryAcquireSRWLockExclusive(raw(self)) != 0 }
     }
 
     #[inline]
diff --git a/library/std/src/sys/windows/locks/rwlock.rs b/library/std/src/sys/windows/locks/rwlock.rs
index fa5ffe5749f2..e69415baac42 100644
--- a/library/std/src/sys/windows/locks/rwlock.rs
+++ b/library/std/src/sys/windows/locks/rwlock.rs
@@ -5,8 +5,6 @@ pub struct RwLock {
     inner: UnsafeCell<c::SRWLOCK>,
 }
 
-pub type MovableRwLock = RwLock;
-
 unsafe impl Send for RwLock {}
 unsafe impl Sync for RwLock {}
 
@@ -16,20 +14,20 @@ impl RwLock {
         RwLock { inner: UnsafeCell::new(c::SRWLOCK_INIT) }
     }
     #[inline]
-    pub unsafe fn read(&self) {
-        c::AcquireSRWLockShared(self.inner.get())
+    pub fn read(&self) {
+        unsafe { c::AcquireSRWLockShared(self.inner.get()) }
     }
     #[inline]
-    pub unsafe fn try_read(&self) -> bool {
-        c::TryAcquireSRWLockShared(self.inner.get()) != 0
+    pub fn try_read(&self) -> bool {
+        unsafe { c::TryAcquireSRWLockShared(self.inner.get()) != 0 }
     }
     #[inline]
-    pub unsafe fn write(&self) {
-        c::AcquireSRWLockExclusive(self.inner.get())
+    pub fn write(&self) {
+        unsafe { c::AcquireSRWLockExclusive(self.inner.get()) }
     }
     #[inline]
-    pub unsafe fn try_write(&self) -> bool {
-        c::TryAcquireSRWLockExclusive(self.inner.get()) != 0
+    pub fn try_write(&self) -> bool {
+        unsafe { c::TryAcquireSRWLockExclusive(self.inner.get()) != 0 }
     }
     #[inline]
     pub unsafe fn read_unlock(&self) {
diff --git a/library/std/src/sys/windows/mod.rs b/library/std/src/sys/windows/mod.rs
index eab9b961279c..e67411e16860 100644
--- a/library/std/src/sys/windows/mod.rs
+++ b/library/std/src/sys/windows/mod.rs
@@ -29,6 +29,7 @@ pub mod path;
 pub mod pipe;
 pub mod process;
 pub mod rand;
+pub mod stdio;
 pub mod thread;
 pub mod thread_local_dtor;
 pub mod thread_local_key;
@@ -36,12 +37,9 @@ pub mod thread_parker;
 pub mod time;
 cfg_if::cfg_if! {
     if #[cfg(not(target_vendor = "uwp"))] {
-        pub mod stdio;
         pub mod stack_overflow;
     } else {
-        pub mod stdio_uwp;
         pub mod stack_overflow_uwp;
-        pub use self::stdio_uwp as stdio;
         pub use self::stack_overflow_uwp as stack_overflow;
     }
 }
diff --git a/library/std/src/sys/windows/pipe.rs b/library/std/src/sys/windows/pipe.rs
index 013c776c476c..9f26acc45205 100644
--- a/library/std/src/sys/windows/pipe.rs
+++ b/library/std/src/sys/windows/pipe.rs
@@ -324,17 +324,18 @@ impl AnonPipe {
         let mut async_result: Option<AsyncResult> = None;
         struct AsyncResult {
             error: u32,
-            transfered: u32,
+            transferred: u32,
         }
 
         // STEP 3: The callback.
         unsafe extern "system" fn callback(
             dwErrorCode: u32,
-            dwNumberOfBytesTransfered: u32,
+            dwNumberOfBytesTransferred: u32,
             lpOverlapped: *mut c::OVERLAPPED,
         ) {
             // Set `async_result` using a pointer smuggled through `hEvent`.
-            let result = AsyncResult { error: dwErrorCode, transfered: dwNumberOfBytesTransfered };
+            let result =
+                AsyncResult { error: dwErrorCode, transferred: dwNumberOfBytesTransferred };
             *(*lpOverlapped).hEvent.cast::<Option<AsyncResult>>() = Some(result);
         }
 
@@ -365,7 +366,7 @@ impl AnonPipe {
         // STEP 4: Return the result.
         // `async_result` is always `Some` at this point
         match result.error {
-            c::ERROR_SUCCESS => Ok(result.transfered as usize),
+            c::ERROR_SUCCESS => Ok(result.transferred as usize),
             error => Err(io::Error::from_raw_os_error(error as _)),
         }
     }
diff --git a/library/std/src/sys/windows/stdio_uwp.rs b/library/std/src/sys/windows/stdio_uwp.rs
deleted file mode 100644
index 32550f796ec6..000000000000
--- a/library/std/src/sys/windows/stdio_uwp.rs
+++ /dev/null
@@ -1,87 +0,0 @@
-#![unstable(issue = "none", feature = "windows_stdio")]
-
-use crate::io;
-use crate::mem::ManuallyDrop;
-use crate::os::windows::io::FromRawHandle;
-use crate::sys::c;
-use crate::sys::handle::Handle;
-
-pub struct Stdin {}
-pub struct Stdout;
-pub struct Stderr;
-
-const MAX_BUFFER_SIZE: usize = 8192;
-pub const STDIN_BUF_SIZE: usize = MAX_BUFFER_SIZE / 2 * 3;
-
-pub fn get_handle(handle_id: c::DWORD) -> io::Result<c::HANDLE> {
-    let handle = unsafe { c::GetStdHandle(handle_id) };
-    if handle == c::INVALID_HANDLE_VALUE {
-        Err(io::Error::last_os_error())
-    } else if handle.is_null() {
-        Err(io::Error::from_raw_os_error(c::ERROR_INVALID_HANDLE as i32))
-    } else {
-        Ok(handle)
-    }
-}
-
-fn write(handle_id: c::DWORD, data: &[u8]) -> io::Result<usize> {
-    let handle = get_handle(handle_id)?;
-    // SAFETY: The handle returned from `get_handle` must be valid and non-null.
-    let handle = unsafe { Handle::from_raw_handle(handle) };
-    ManuallyDrop::new(handle).write(data)
-}
-
-impl Stdin {
-    pub const fn new() -> Stdin {
-        Stdin {}
-    }
-}
-
-impl io::Read for Stdin {
-    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
-        let handle = get_handle(c::STD_INPUT_HANDLE)?;
-        // SAFETY: The handle returned from `get_handle` must be valid and non-null.
-        let handle = unsafe { Handle::from_raw_handle(handle) };
-        ManuallyDrop::new(handle).read(buf)
-    }
-}
-
-impl Stdout {
-    pub const fn new() -> Stdout {
-        Stdout
-    }
-}
-
-impl io::Write for Stdout {
-    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
-        write(c::STD_OUTPUT_HANDLE, buf)
-    }
-
-    fn flush(&mut self) -> io::Result<()> {
-        Ok(())
-    }
-}
-
-impl Stderr {
-    pub const fn new() -> Stderr {
-        Stderr
-    }
-}
-
-impl io::Write for Stderr {
-    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
-        write(c::STD_ERROR_HANDLE, buf)
-    }
-
-    fn flush(&mut self) -> io::Result<()> {
-        Ok(())
-    }
-}
-
-pub fn is_ebadf(err: &io::Error) -> bool {
-    err.raw_os_error() == Some(c::ERROR_INVALID_HANDLE as i32)
-}
-
-pub fn panic_output() -> Option<impl io::Write> {
-    Some(Stderr::new())
-}
diff --git a/library/std/src/sys_common/condvar.rs b/library/std/src/sys_common/condvar.rs
deleted file mode 100644
index 8bc5b24115d1..000000000000
--- a/library/std/src/sys_common/condvar.rs
+++ /dev/null
@@ -1,57 +0,0 @@
-use crate::sys::locks as imp;
-use crate::sys_common::mutex::MovableMutex;
-use crate::time::Duration;
-
-mod check;
-
-type CondvarCheck = <imp::MovableMutex as check::CondvarCheck>::Check;
-
-/// An OS-based condition variable.
-pub struct Condvar {
-    inner: imp::MovableCondvar,
-    check: CondvarCheck,
-}
-
-impl Condvar {
-    /// Creates a new condition variable for use.
-    #[inline]
-    #[rustc_const_stable(feature = "const_locks", since = "1.63.0")]
-    pub const fn new() -> Self {
-        Self { inner: imp::MovableCondvar::new(), check: CondvarCheck::new() }
-    }
-
-    /// Signals one waiter on this condition variable to wake up.
-    #[inline]
-    pub fn notify_one(&self) {
-        unsafe { self.inner.notify_one() };
-    }
-
-    /// Awakens all current waiters on this condition variable.
-    #[inline]
-    pub fn notify_all(&self) {
-        unsafe { self.inner.notify_all() };
-    }
-
-    /// Waits for a signal on the specified mutex.
-    ///
-    /// Behavior is undefined if the mutex is not locked by the current thread.
-    ///
-    /// May panic if used with more than one mutex.
-    #[inline]
-    pub unsafe fn wait(&self, mutex: &MovableMutex) {
-        self.check.verify(mutex);
-        self.inner.wait(mutex.raw())
-    }
-
-    /// Waits for a signal on the specified mutex with a timeout duration
-    /// specified by `dur` (a relative time into the future).
-    ///
-    /// Behavior is undefined if the mutex is not locked by the current thread.
-    ///
-    /// May panic if used with more than one mutex.
-    #[inline]
-    pub unsafe fn wait_timeout(&self, mutex: &MovableMutex, dur: Duration) -> bool {
-        self.check.verify(mutex);
-        self.inner.wait_timeout(mutex.raw(), dur)
-    }
-}
diff --git a/library/std/src/sys_common/condvar/check.rs b/library/std/src/sys_common/condvar/check.rs
deleted file mode 100644
index 4ac9e62bf869..000000000000
--- a/library/std/src/sys_common/condvar/check.rs
+++ /dev/null
@@ -1,58 +0,0 @@
-use crate::ptr;
-use crate::sync::atomic::{AtomicPtr, Ordering};
-use crate::sys::locks as imp;
-use crate::sys_common::lazy_box::{LazyBox, LazyInit};
-use crate::sys_common::mutex::MovableMutex;
-
-pub trait CondvarCheck {
-    type Check;
-}
-
-/// For boxed mutexes, a `Condvar` will check it's only ever used with the same
-/// mutex, based on its (stable) address.
-impl<T: LazyInit> CondvarCheck for LazyBox<T> {
-    type Check = SameMutexCheck;
-}
-
-pub struct SameMutexCheck {
-    addr: AtomicPtr<()>,
-}
-
-#[allow(dead_code)]
-impl SameMutexCheck {
-    pub const fn new() -> Self {
-        Self { addr: AtomicPtr::new(ptr::null_mut()) }
-    }
-    pub fn verify(&self, mutex: &MovableMutex) {
-        let addr = mutex.raw() as *const imp::Mutex as *const () as *mut _;
-        // Relaxed is okay here because we never read through `self.addr`, and only use it to
-        // compare addresses.
-        match self.addr.compare_exchange(
-            ptr::null_mut(),
-            addr,
-            Ordering::Relaxed,
-            Ordering::Relaxed,
-        ) {
-            Ok(_) => {}               // Stored the address
-            Err(n) if n == addr => {} // Lost a race to store the same address
-            _ => panic!("attempted to use a condition variable with two mutexes"),
-        }
-    }
-}
-
-/// Unboxed mutexes may move, so `Condvar` can not require its address to stay
-/// constant.
-impl CondvarCheck for imp::Mutex {
-    type Check = NoCheck;
-}
-
-pub struct NoCheck;
-
-#[allow(dead_code)]
-impl NoCheck {
-    #[rustc_const_stable(feature = "const_locks", since = "1.63.0")]
-    pub const fn new() -> Self {
-        Self
-    }
-    pub fn verify(&self, _: &MovableMutex) {}
-}
diff --git a/library/std/src/sys_common/mod.rs b/library/std/src/sys_common/mod.rs
index 8c19f9332dc5..069b13e9d85e 100644
--- a/library/std/src/sys_common/mod.rs
+++ b/library/std/src/sys_common/mod.rs
@@ -21,16 +21,13 @@
 mod tests;
 
 pub mod backtrace;
-pub mod condvar;
 pub mod fs;
 pub mod io;
 pub mod lazy_box;
 pub mod memchr;
-pub mod mutex;
 pub mod once;
 pub mod process;
 pub mod remutex;
-pub mod rwlock;
 pub mod thread;
 pub mod thread_info;
 pub mod thread_local_dtor;
diff --git a/library/std/src/sys_common/mutex.rs b/library/std/src/sys_common/mutex.rs
deleted file mode 100644
index 98046f20f896..000000000000
--- a/library/std/src/sys_common/mutex.rs
+++ /dev/null
@@ -1,50 +0,0 @@
-use crate::sys::locks as imp;
-
-/// An OS-based mutual exclusion lock.
-///
-/// This mutex cleans up its resources in its `Drop` implementation, may safely
-/// be moved (when not borrowed), and does not cause UB when used reentrantly.
-///
-/// This mutex does not implement poisoning.
-///
-/// This is either a wrapper around `LazyBox<imp::Mutex>` or `imp::Mutex`,
-/// depending on the platform. It is boxed on platforms where `imp::Mutex` may
-/// not be moved.
-pub struct MovableMutex(imp::MovableMutex);
-
-unsafe impl Sync for MovableMutex {}
-
-impl MovableMutex {
-    /// Creates a new mutex.
-    #[inline]
-    #[rustc_const_stable(feature = "const_locks", since = "1.63.0")]
-    pub const fn new() -> Self {
-        Self(imp::MovableMutex::new())
-    }
-
-    pub(super) fn raw(&self) -> &imp::Mutex {
-        &self.0
-    }
-
-    /// Locks the mutex blocking the current thread until it is available.
-    #[inline]
-    pub fn raw_lock(&self) {
-        unsafe { self.0.lock() }
-    }
-
-    /// Attempts to lock the mutex without blocking, returning whether it was
-    /// successfully acquired or not.
-    #[inline]
-    pub fn try_lock(&self) -> bool {
-        unsafe { self.0.try_lock() }
-    }
-
-    /// Unlocks the mutex.
-    ///
-    /// Behavior is undefined if the current thread does not actually hold the
-    /// mutex.
-    #[inline]
-    pub unsafe fn raw_unlock(&self) {
-        self.0.unlock()
-    }
-}
diff --git a/library/std/src/sys_common/remutex.rs b/library/std/src/sys_common/remutex.rs
index b448ae3a9977..4c054da64714 100644
--- a/library/std/src/sys_common/remutex.rs
+++ b/library/std/src/sys_common/remutex.rs
@@ -1,11 +1,11 @@
 #[cfg(all(test, not(target_os = "emscripten")))]
 mod tests;
 
-use super::mutex as sys;
 use crate::cell::UnsafeCell;
 use crate::ops::Deref;
 use crate::panic::{RefUnwindSafe, UnwindSafe};
 use crate::sync::atomic::{AtomicUsize, Ordering::Relaxed};
+use crate::sys::locks as sys;
 
 /// A re-entrant mutual exclusion
 ///
@@ -39,7 +39,7 @@ use crate::sync::atomic::{AtomicUsize, Ordering::Relaxed};
 /// synchronization is left to the mutex, making relaxed memory ordering for
 /// the `owner` field fine in all cases.
 pub struct ReentrantMutex<T> {
-    mutex: sys::MovableMutex,
+    mutex: sys::Mutex,
     owner: AtomicUsize,
     lock_count: UnsafeCell<u32>,
     data: T,
@@ -74,7 +74,7 @@ impl<T> ReentrantMutex<T> {
     /// Creates a new reentrant mutex in an unlocked state.
     pub const fn new(t: T) -> ReentrantMutex<T> {
         ReentrantMutex {
-            mutex: sys::MovableMutex::new(),
+            mutex: sys::Mutex::new(),
             owner: AtomicUsize::new(0),
             lock_count: UnsafeCell::new(0),
             data: t,
@@ -100,7 +100,7 @@ impl<T> ReentrantMutex<T> {
             if self.owner.load(Relaxed) == this_thread {
                 self.increment_lock_count();
             } else {
-                self.mutex.raw_lock();
+                self.mutex.lock();
                 self.owner.store(this_thread, Relaxed);
                 debug_assert_eq!(*self.lock_count.get(), 0);
                 *self.lock_count.get() = 1;
@@ -162,7 +162,7 @@ impl<T> Drop for ReentrantMutexGuard<'_, T> {
             *self.lock.lock_count.get() -= 1;
             if *self.lock.lock_count.get() == 0 {
                 self.lock.owner.store(0, Relaxed);
-                self.lock.mutex.raw_unlock();
+                self.lock.mutex.unlock();
             }
         }
     }
diff --git a/library/std/src/sys_common/rwlock.rs b/library/std/src/sys_common/rwlock.rs
deleted file mode 100644
index 042981dac60b..000000000000
--- a/library/std/src/sys_common/rwlock.rs
+++ /dev/null
@@ -1,71 +0,0 @@
-use crate::sys::locks as imp;
-
-/// An OS-based reader-writer lock.
-///
-/// This rwlock cleans up its resources in its `Drop` implementation and may
-/// safely be moved (when not borrowed).
-///
-/// This rwlock does not implement poisoning.
-///
-/// This is either a wrapper around `LazyBox<imp::RwLock>` or `imp::RwLock`,
-/// depending on the platform. It is boxed on platforms where `imp::RwLock` may
-/// not be moved.
-pub struct MovableRwLock(imp::MovableRwLock);
-
-impl MovableRwLock {
-    /// Creates a new reader-writer lock for use.
-    #[inline]
-    #[rustc_const_stable(feature = "const_locks", since = "1.63.0")]
-    pub const fn new() -> Self {
-        Self(imp::MovableRwLock::new())
-    }
-
-    /// Acquires shared access to the underlying lock, blocking the current
-    /// thread to do so.
-    #[inline]
-    pub fn read(&self) {
-        unsafe { self.0.read() }
-    }
-
-    /// Attempts to acquire shared access to this lock, returning whether it
-    /// succeeded or not.
-    ///
-    /// This function does not block the current thread.
-    #[inline]
-    pub fn try_read(&self) -> bool {
-        unsafe { self.0.try_read() }
-    }
-
-    /// Acquires write access to the underlying lock, blocking the current thread
-    /// to do so.
-    #[inline]
-    pub fn write(&self) {
-        unsafe { self.0.write() }
-    }
-
-    /// Attempts to acquire exclusive access to this lock, returning whether it
-    /// succeeded or not.
-    ///
-    /// This function does not block the current thread.
-    #[inline]
-    pub fn try_write(&self) -> bool {
-        unsafe { self.0.try_write() }
-    }
-
-    /// Unlocks previously acquired shared access to this lock.
-    ///
-    /// Behavior is undefined if the current thread does not have shared access.
-    #[inline]
-    pub unsafe fn read_unlock(&self) {
-        self.0.read_unlock()
-    }
-
-    /// Unlocks previously acquired exclusive access to this lock.
-    ///
-    /// Behavior is undefined if the current thread does not currently have
-    /// exclusive access.
-    #[inline]
-    pub unsafe fn write_unlock(&self) {
-        self.0.write_unlock()
-    }
-}
diff --git a/library/std/src/thread/local/tests.rs b/library/std/src/thread/local/tests.rs
index 1df1ca758c05..80dc4c038d61 100644
--- a/library/std/src/thread/local/tests.rs
+++ b/library/std/src/thread/local/tests.rs
@@ -1,15 +1,34 @@
 use crate::cell::{Cell, UnsafeCell};
 use crate::sync::atomic::{AtomicU8, Ordering};
-use crate::sync::mpsc::{channel, Sender};
+use crate::sync::{Arc, Condvar, Mutex};
 use crate::thread::{self, LocalKey};
 use crate::thread_local;
 
-struct Foo(Sender<()>);
+#[derive(Clone, Default)]
+struct Signal(Arc<(Mutex<bool>, Condvar)>);
+
+impl Signal {
+    fn notify(&self) {
+        let (set, cvar) = &*self.0;
+        *set.lock().unwrap() = true;
+        cvar.notify_one();
+    }
+
+    fn wait(&self) {
+        let (set, cvar) = &*self.0;
+        let mut set = set.lock().unwrap();
+        while !*set {
+            set = cvar.wait(set).unwrap();
+        }
+    }
+}
+
+struct Foo(Signal);
 
 impl Drop for Foo {
     fn drop(&mut self) {
-        let Foo(ref s) = *self;
-        s.send(()).unwrap();
+        let Foo(ref f) = *self;
+        f.notify();
     }
 }
 
@@ -69,14 +88,15 @@ fn smoke_dtor() {
     run(&FOO2);
 
     fn run(key: &'static LocalKey<UnsafeCell<Option<Foo>>>) {
-        let (tx, rx) = channel();
+        let signal = Signal::default();
+        let signal2 = signal.clone();
         let t = thread::spawn(move || unsafe {
-            let mut tx = Some(tx);
+            let mut signal = Some(signal2);
             key.with(|f| {
-                *f.get() = Some(Foo(tx.take().unwrap()));
+                *f.get() = Some(Foo(signal.take().unwrap()));
             });
         });
-        rx.recv().unwrap();
+        signal.wait();
         t.join().unwrap();
     }
 }
@@ -165,48 +185,50 @@ fn self_referential() {
 // requires the destructor to be run to pass the test).
 #[test]
 fn dtors_in_dtors_in_dtors() {
-    struct S1(Sender<()>);
+    struct S1(Signal);
     thread_local!(static K1: UnsafeCell<Option<S1>> = UnsafeCell::new(None));
     thread_local!(static K2: UnsafeCell<Option<Foo>> = UnsafeCell::new(None));
 
     impl Drop for S1 {
         fn drop(&mut self) {
-            let S1(ref tx) = *self;
+            let S1(ref signal) = *self;
             unsafe {
-                let _ = K2.try_with(|s| *s.get() = Some(Foo(tx.clone())));
+                let _ = K2.try_with(|s| *s.get() = Some(Foo(signal.clone())));
             }
         }
     }
 
-    let (tx, rx) = channel();
+    let signal = Signal::default();
+    let signal2 = signal.clone();
     let _t = thread::spawn(move || unsafe {
-        let mut tx = Some(tx);
-        K1.with(|s| *s.get() = Some(S1(tx.take().unwrap())));
+        let mut signal = Some(signal2);
+        K1.with(|s| *s.get() = Some(S1(signal.take().unwrap())));
     });
-    rx.recv().unwrap();
+    signal.wait();
 }
 
 #[test]
 fn dtors_in_dtors_in_dtors_const_init() {
-    struct S1(Sender<()>);
+    struct S1(Signal);
     thread_local!(static K1: UnsafeCell<Option<S1>> = const { UnsafeCell::new(None) });
     thread_local!(static K2: UnsafeCell<Option<Foo>> = const { UnsafeCell::new(None) });
 
     impl Drop for S1 {
         fn drop(&mut self) {
-            let S1(ref tx) = *self;
+            let S1(ref signal) = *self;
             unsafe {
-                let _ = K2.try_with(|s| *s.get() = Some(Foo(tx.clone())));
+                let _ = K2.try_with(|s| *s.get() = Some(Foo(signal.clone())));
             }
         }
     }
 
-    let (tx, rx) = channel();
+    let signal = Signal::default();
+    let signal2 = signal.clone();
     let _t = thread::spawn(move || unsafe {
-        let mut tx = Some(tx);
-        K1.with(|s| *s.get() = Some(S1(tx.take().unwrap())));
+        let mut signal = Some(signal2);
+        K1.with(|s| *s.get() = Some(S1(signal.take().unwrap())));
     });
-    rx.recv().unwrap();
+    signal.wait();
 }
 
 // This test tests that TLS destructors have run before the thread joins. The
diff --git a/library/std/src/thread/tests.rs b/library/std/src/thread/tests.rs
index dfb8765ab4ee..6c9ce6fa0ddb 100644
--- a/library/std/src/thread/tests.rs
+++ b/library/std/src/thread/tests.rs
@@ -37,6 +37,37 @@ fn test_named_thread() {
         .unwrap();
 }
 
+#[cfg(any(
+    // Note: musl didn't add pthread_getname_np until 1.2.3
+    all(target_os = "linux", target_env = "gnu"),
+    target_os = "macos",
+    target_os = "ios",
+    target_os = "watchos"
+))]
+#[test]
+fn test_named_thread_truncation() {
+    use crate::ffi::CStr;
+
+    let long_name = crate::iter::once("test_named_thread_truncation")
+        .chain(crate::iter::repeat(" yada").take(100))
+        .collect::<String>();
+
+    let result = Builder::new().name(long_name.clone()).spawn(move || {
+        // Rust remembers the full thread name itself.
+        assert_eq!(thread::current().name(), Some(long_name.as_str()));
+
+        // But the system is limited -- make sure we successfully set a truncation.
+        let mut buf = vec![0u8; long_name.len() + 1];
+        unsafe {
+            libc::pthread_getname_np(libc::pthread_self(), buf.as_mut_ptr().cast(), buf.len());
+        }
+        let cstr = CStr::from_bytes_until_nul(&buf).unwrap();
+        assert!(cstr.to_bytes().len() > 0);
+        assert!(long_name.as_bytes().starts_with(cstr.to_bytes()));
+    });
+    result.unwrap().join().unwrap();
+}
+
 #[test]
 #[should_panic]
 fn test_invalid_named_thread() {
diff --git a/library/std/src/time.rs b/library/std/src/time.rs
index 34e18b5fa877..ecd06ebf743a 100644
--- a/library/std/src/time.rs
+++ b/library/std/src/time.rs
@@ -43,7 +43,7 @@ use crate::sys_common::{FromInner, IntoInner};
 #[stable(feature = "time", since = "1.3.0")]
 pub use core::time::Duration;
 
-#[stable(feature = "duration_checked_float", since = "CURRENT_RUSTC_VERSION")]
+#[stable(feature = "duration_checked_float", since = "1.66.0")]
 pub use core::time::TryFromFloatSecsError;
 
 /// A measurement of a monotonically nondecreasing clock.
diff --git a/library/test/src/console.rs b/library/test/src/console.rs
index b1270c272710..8cb88016b23a 100644
--- a/library/test/src/console.rs
+++ b/library/test/src/console.rs
@@ -228,9 +228,9 @@ fn on_test_event(
     out: &mut dyn OutputFormatter,
 ) -> io::Result<()> {
     match (*event).clone() {
-        TestEvent::TeFiltered(ref filtered_tests, shuffle_seed) => {
-            st.total = filtered_tests.len();
-            out.write_run_start(filtered_tests.len(), shuffle_seed)?;
+        TestEvent::TeFiltered(filtered_tests, shuffle_seed) => {
+            st.total = filtered_tests;
+            out.write_run_start(filtered_tests, shuffle_seed)?;
         }
         TestEvent::TeFilteredOut(filtered_out) => {
             st.filtered_out = filtered_out;
diff --git a/library/test/src/event.rs b/library/test/src/event.rs
index 6ff1a615eb4d..80281ebd2d4c 100644
--- a/library/test/src/event.rs
+++ b/library/test/src/event.rs
@@ -28,7 +28,7 @@ impl CompletedTest {
 
 #[derive(Debug, Clone)]
 pub enum TestEvent {
-    TeFiltered(Vec<TestDesc>, Option<u64>),
+    TeFiltered(usize, Option<u64>),
     TeWait(TestDesc),
     TeResult(CompletedTest),
     TeTimeout(TestDesc),
diff --git a/library/test/src/lib.rs b/library/test/src/lib.rs
index 4de694557982..27320e8dbc5a 100644
--- a/library/test/src/lib.rs
+++ b/library/test/src/lib.rs
@@ -20,6 +20,7 @@
 #![feature(is_terminal)]
 #![feature(staged_api)]
 #![feature(process_exitcode_internals)]
+#![feature(panic_can_unwind)]
 #![feature(test)]
 
 // Public reexports
@@ -39,7 +40,7 @@ pub mod test {
         cli::{parse_opts, TestOpts},
         filter_tests,
         helpers::metrics::{Metric, MetricMap},
-        options::{Concurrent, Options, RunIgnored, RunStrategy, ShouldPanic},
+        options::{Options, RunIgnored, RunStrategy, ShouldPanic},
         run_test, test_main, test_main_static,
         test_result::{TestResult, TrFailed, TrFailedMsg, TrIgnored, TrOk},
         time::{TestExecTime, TestTimeOptions},
@@ -54,6 +55,7 @@ use std::{
     collections::VecDeque,
     env, io,
     io::prelude::Write,
+    mem::ManuallyDrop,
     panic::{self, catch_unwind, AssertUnwindSafe, PanicInfo},
     process::{self, Command, Termination},
     sync::mpsc::{channel, Sender},
@@ -83,7 +85,7 @@ use event::{CompletedTest, TestEvent};
 use helpers::concurrency::get_concurrency;
 use helpers::exit_code::get_exit_code;
 use helpers::shuffle::{get_shuffle_seed, shuffle_tests};
-use options::{Concurrent, RunStrategy};
+use options::RunStrategy;
 use test_result::*;
 use time::TestExecTime;
 
@@ -112,6 +114,29 @@ pub fn test_main(args: &[String], tests: Vec<TestDescAndFn>, options: Option<Opt
             process::exit(ERROR_EXIT_CODE);
         }
     } else {
+        if !opts.nocapture {
+            // If we encounter a non-unwinding panic, flush any captured output from the current test,
+            // and stop  capturing output to ensure that the non-unwinding panic message is visible.
+            // We also acquire the locks for both output streams to prevent output from other threads
+            // from interleaving with the panic message or appearing after it.
+            let builtin_panic_hook = panic::take_hook();
+            let hook = Box::new({
+                move |info: &'_ PanicInfo<'_>| {
+                    if !info.can_unwind() {
+                        std::mem::forget(std::io::stderr().lock());
+                        let mut stdout = ManuallyDrop::new(std::io::stdout().lock());
+                        if let Some(captured) = io::set_output_capture(None) {
+                            if let Ok(data) = captured.lock() {
+                                let _ = stdout.write_all(&data);
+                                let _ = stdout.flush();
+                            }
+                        }
+                    }
+                    builtin_panic_hook(info);
+                }
+            });
+            panic::set_hook(hook);
+        }
         match console::run_tests_console(&opts, tests) {
             Ok(true) => {}
             Ok(false) => process::exit(ERROR_EXIT_CODE),
@@ -194,6 +219,38 @@ pub fn assert_test_result<T: Termination>(result: T) -> Result<(), String> {
     }
 }
 
+struct FilteredTests {
+    tests: Vec<(TestId, TestDescAndFn)>,
+    benchs: Vec<(TestId, TestDescAndFn)>,
+    next_id: usize,
+}
+
+impl FilteredTests {
+    fn add_bench(&mut self, desc: TestDesc, testfn: TestFn) {
+        let test = TestDescAndFn { desc, testfn };
+        self.benchs.push((TestId(self.next_id), test));
+        self.next_id += 1;
+    }
+    fn add_test(&mut self, desc: TestDesc, testfn: TestFn) {
+        let test = TestDescAndFn { desc, testfn };
+        self.tests.push((TestId(self.next_id), test));
+        self.next_id += 1;
+    }
+    fn add_bench_as_test(
+        &mut self,
+        desc: TestDesc,
+        benchfn: impl Fn(&mut Bencher) -> Result<(), String> + Send + 'static,
+    ) {
+        let testfn = DynTestFn(Box::new(move || {
+            bench::run_once(|b| __rust_begin_short_backtrace(|| benchfn(b)))
+        }));
+        self.add_test(desc, testfn);
+    }
+    fn total_len(&self) -> usize {
+        self.tests.len() + self.benchs.len()
+    }
+}
+
 pub fn run_tests<F>(
     opts: &TestOpts,
     tests: Vec<TestDescAndFn>,
@@ -210,6 +267,19 @@ where
         join_handle: Option<thread::JoinHandle<()>>,
     }
 
+    impl RunningTest {
+        fn join(self, completed_test: &mut CompletedTest) {
+            if let Some(join_handle) = self.join_handle {
+                if let Err(_) = join_handle.join() {
+                    if let TrOk = completed_test.result {
+                        completed_test.result =
+                            TrFailedMsg("panicked after reporting success".to_string());
+                    }
+                }
+            }
+        }
+    }
+
     // Use a deterministic hasher
     type TestMap =
         HashMap<TestId, RunningTest, BuildHasherDefault<collections::hash_map::DefaultHasher>>;
@@ -222,45 +292,51 @@ where
 
     let tests_len = tests.len();
 
-    let mut filtered_tests = filter_tests(opts, tests);
-    if !opts.bench_benchmarks {
-        filtered_tests = convert_benchmarks_to_tests(filtered_tests);
+    let mut filtered = FilteredTests { tests: Vec::new(), benchs: Vec::new(), next_id: 0 };
+
+    for test in filter_tests(opts, tests) {
+        let mut desc = test.desc;
+        desc.name = desc.name.with_padding(test.testfn.padding());
+
+        match test.testfn {
+            DynBenchFn(benchfn) => {
+                if opts.bench_benchmarks {
+                    filtered.add_bench(desc, DynBenchFn(benchfn));
+                } else {
+                    filtered.add_bench_as_test(desc, benchfn);
+                }
+            }
+            StaticBenchFn(benchfn) => {
+                if opts.bench_benchmarks {
+                    filtered.add_bench(desc, StaticBenchFn(benchfn));
+                } else {
+                    filtered.add_bench_as_test(desc, benchfn);
+                }
+            }
+            testfn => {
+                filtered.add_test(desc, testfn);
+            }
+        };
     }
 
-    let filtered_tests = {
-        let mut filtered_tests = filtered_tests;
-        for test in filtered_tests.iter_mut() {
-            test.desc.name = test.desc.name.with_padding(test.testfn.padding());
-        }
-
-        filtered_tests
-    };
-
-    let filtered_out = tests_len - filtered_tests.len();
+    let filtered_out = tests_len - filtered.total_len();
     let event = TestEvent::TeFilteredOut(filtered_out);
     notify_about_test_event(event)?;
 
-    let filtered_descs = filtered_tests.iter().map(|t| t.desc.clone()).collect();
-
     let shuffle_seed = get_shuffle_seed(opts);
 
-    let event = TestEvent::TeFiltered(filtered_descs, shuffle_seed);
+    let event = TestEvent::TeFiltered(filtered.total_len(), shuffle_seed);
     notify_about_test_event(event)?;
 
-    let (mut filtered_tests, filtered_benchs): (Vec<_>, _) = filtered_tests
-        .into_iter()
-        .enumerate()
-        .map(|(i, e)| (TestId(i), e))
-        .partition(|(_, e)| matches!(e.testfn, StaticTestFn(_) | DynTestFn(_)));
-
     let concurrency = opts.test_threads.unwrap_or_else(get_concurrency);
 
+    let mut remaining = filtered.tests;
     if let Some(shuffle_seed) = shuffle_seed {
-        shuffle_tests(shuffle_seed, &mut filtered_tests);
+        shuffle_tests(shuffle_seed, &mut remaining);
     }
     // Store the tests in a VecDeque so we can efficiently remove the first element to run the
     // tests in the order they were passed (unless shuffled).
-    let mut remaining = VecDeque::from(filtered_tests);
+    let mut remaining = VecDeque::from(remaining);
     let mut pending = 0;
 
     let (tx, rx) = channel::<CompletedTest>();
@@ -303,10 +379,10 @@ where
             let (id, test) = remaining.pop_front().unwrap();
             let event = TestEvent::TeWait(test.desc.clone());
             notify_about_test_event(event)?;
-            let join_handle =
-                run_test(opts, !opts.run_tests, id, test, run_strategy, tx.clone(), Concurrent::No);
-            assert!(join_handle.is_none());
-            let completed_test = rx.recv().unwrap();
+            let join_handle = run_test(opts, !opts.run_tests, id, test, run_strategy, tx.clone());
+            // Wait for the test to complete.
+            let mut completed_test = rx.recv().unwrap();
+            RunningTest { join_handle }.join(&mut completed_test);
 
             let event = TestEvent::TeResult(completed_test);
             notify_about_test_event(event)?;
@@ -320,15 +396,8 @@ where
 
                 let event = TestEvent::TeWait(desc.clone());
                 notify_about_test_event(event)?; //here no pad
-                let join_handle = run_test(
-                    opts,
-                    !opts.run_tests,
-                    id,
-                    test,
-                    run_strategy,
-                    tx.clone(),
-                    Concurrent::Yes,
-                );
+                let join_handle =
+                    run_test(opts, !opts.run_tests, id, test, run_strategy, tx.clone());
                 running_tests.insert(id, RunningTest { join_handle });
                 timeout_queue.push_back(TimeoutEntry { id, desc, timeout });
                 pending += 1;
@@ -360,14 +429,7 @@ where
 
             let mut completed_test = res.unwrap();
             let running_test = running_tests.remove(&completed_test.id).unwrap();
-            if let Some(join_handle) = running_test.join_handle {
-                if let Err(_) = join_handle.join() {
-                    if let TrOk = completed_test.result {
-                        completed_test.result =
-                            TrFailedMsg("panicked after reporting success".to_string());
-                    }
-                }
-            }
+            running_test.join(&mut completed_test);
 
             let event = TestEvent::TeResult(completed_test);
             notify_about_test_event(event)?;
@@ -377,11 +439,13 @@ where
 
     if opts.bench_benchmarks {
         // All benchmarks run at the end, in serial.
-        for (id, b) in filtered_benchs {
+        for (id, b) in filtered.benchs {
             let event = TestEvent::TeWait(b.desc.clone());
             notify_about_test_event(event)?;
-            run_test(opts, false, id, b, run_strategy, tx.clone(), Concurrent::No);
-            let completed_test = rx.recv().unwrap();
+            let join_handle = run_test(opts, false, id, b, run_strategy, tx.clone());
+            // Wait for the test to complete.
+            let mut completed_test = rx.recv().unwrap();
+            RunningTest { join_handle }.join(&mut completed_test);
 
             let event = TestEvent::TeResult(completed_test);
             notify_about_test_event(event)?;
@@ -407,7 +471,9 @@ pub fn filter_tests(opts: &TestOpts, tests: Vec<TestDescAndFn>) -> Vec<TestDescA
     }
 
     // Skip tests that match any of the skip filters
-    filtered.retain(|test| !opts.skip.iter().any(|sf| matches_filter(test, sf)));
+    if !opts.skip.is_empty() {
+        filtered.retain(|test| !opts.skip.iter().any(|sf| matches_filter(test, sf)));
+    }
 
     // Excludes #[should_panic] tests
     if opts.exclude_should_panic {
@@ -455,7 +521,6 @@ pub fn run_test(
     test: TestDescAndFn,
     strategy: RunStrategy,
     monitor_ch: Sender<CompletedTest>,
-    concurrency: Concurrent,
 ) -> Option<thread::JoinHandle<()>> {
     let TestDescAndFn { desc, testfn } = test;
 
@@ -473,7 +538,6 @@ pub fn run_test(
     struct TestRunOpts {
         pub strategy: RunStrategy,
         pub nocapture: bool,
-        pub concurrency: Concurrent,
         pub time: Option<time::TestTimeOptions>,
     }
 
@@ -484,7 +548,6 @@ pub fn run_test(
         testfn: Box<dyn FnOnce() -> Result<(), String> + Send>,
         opts: TestRunOpts,
     ) -> Option<thread::JoinHandle<()>> {
-        let concurrency = opts.concurrency;
         let name = desc.name.clone();
 
         let runtest = move || match opts.strategy {
@@ -511,7 +574,7 @@ pub fn run_test(
         // the test synchronously, regardless of the concurrency
         // level.
         let supports_threads = !cfg!(target_os = "emscripten") && !cfg!(target_family = "wasm");
-        if concurrency == Concurrent::Yes && supports_threads {
+        if supports_threads {
             let cfg = thread::Builder::new().name(name.as_slice().to_owned());
             let mut runtest = Arc::new(Mutex::new(Some(runtest)));
             let runtest2 = runtest.clone();
@@ -532,7 +595,7 @@ pub fn run_test(
     }
 
     let test_run_opts =
-        TestRunOpts { strategy, nocapture: opts.nocapture, concurrency, time: opts.time_options };
+        TestRunOpts { strategy, nocapture: opts.nocapture, time: opts.time_options };
 
     match testfn {
         DynBenchFn(benchfn) => {
diff --git a/library/test/src/options.rs b/library/test/src/options.rs
index baf36b5f1d85..75ec0b616e19 100644
--- a/library/test/src/options.rs
+++ b/library/test/src/options.rs
@@ -1,12 +1,5 @@
 //! Enums denoting options for test execution.
 
-/// Whether to execute tests concurrently or not
-#[derive(Copy, Clone, Debug, PartialEq, Eq)]
-pub enum Concurrent {
-    Yes,
-    No,
-}
-
 /// Number of times to run a benchmarked function
 #[derive(Clone, PartialEq, Eq)]
 pub enum BenchMode {
diff --git a/library/test/src/tests.rs b/library/test/src/tests.rs
index b54be64efcfe..7b2e6707f9d1 100644
--- a/library/test/src/tests.rs
+++ b/library/test/src/tests.rs
@@ -102,7 +102,7 @@ pub fn do_not_run_ignored_tests() {
         testfn: DynTestFn(Box::new(f)),
     };
     let (tx, rx) = channel();
-    run_test(&TestOpts::new(), false, TestId(0), desc, RunStrategy::InProcess, tx, Concurrent::No);
+    run_test(&TestOpts::new(), false, TestId(0), desc, RunStrategy::InProcess, tx);
     let result = rx.recv().unwrap().result;
     assert_ne!(result, TrOk);
 }
@@ -125,7 +125,7 @@ pub fn ignored_tests_result_in_ignored() {
         testfn: DynTestFn(Box::new(f)),
     };
     let (tx, rx) = channel();
-    run_test(&TestOpts::new(), false, TestId(0), desc, RunStrategy::InProcess, tx, Concurrent::No);
+    run_test(&TestOpts::new(), false, TestId(0), desc, RunStrategy::InProcess, tx);
     let result = rx.recv().unwrap().result;
     assert_eq!(result, TrIgnored);
 }
@@ -150,7 +150,7 @@ fn test_should_panic() {
         testfn: DynTestFn(Box::new(f)),
     };
     let (tx, rx) = channel();
-    run_test(&TestOpts::new(), false, TestId(0), desc, RunStrategy::InProcess, tx, Concurrent::No);
+    run_test(&TestOpts::new(), false, TestId(0), desc, RunStrategy::InProcess, tx);
     let result = rx.recv().unwrap().result;
     assert_eq!(result, TrOk);
 }
@@ -175,7 +175,7 @@ fn test_should_panic_good_message() {
         testfn: DynTestFn(Box::new(f)),
     };
     let (tx, rx) = channel();
-    run_test(&TestOpts::new(), false, TestId(0), desc, RunStrategy::InProcess, tx, Concurrent::No);
+    run_test(&TestOpts::new(), false, TestId(0), desc, RunStrategy::InProcess, tx);
     let result = rx.recv().unwrap().result;
     assert_eq!(result, TrOk);
 }
@@ -205,7 +205,7 @@ fn test_should_panic_bad_message() {
         testfn: DynTestFn(Box::new(f)),
     };
     let (tx, rx) = channel();
-    run_test(&TestOpts::new(), false, TestId(0), desc, RunStrategy::InProcess, tx, Concurrent::No);
+    run_test(&TestOpts::new(), false, TestId(0), desc, RunStrategy::InProcess, tx);
     let result = rx.recv().unwrap().result;
     assert_eq!(result, TrFailedMsg(failed_msg.to_string()));
 }
@@ -239,7 +239,7 @@ fn test_should_panic_non_string_message_type() {
         testfn: DynTestFn(Box::new(f)),
     };
     let (tx, rx) = channel();
-    run_test(&TestOpts::new(), false, TestId(0), desc, RunStrategy::InProcess, tx, Concurrent::No);
+    run_test(&TestOpts::new(), false, TestId(0), desc, RunStrategy::InProcess, tx);
     let result = rx.recv().unwrap().result;
     assert_eq!(result, TrFailedMsg(failed_msg));
 }
@@ -267,15 +267,7 @@ fn test_should_panic_but_succeeds() {
             testfn: DynTestFn(Box::new(f)),
         };
         let (tx, rx) = channel();
-        run_test(
-            &TestOpts::new(),
-            false,
-            TestId(0),
-            desc,
-            RunStrategy::InProcess,
-            tx,
-            Concurrent::No,
-        );
+        run_test(&TestOpts::new(), false, TestId(0), desc, RunStrategy::InProcess, tx);
         let result = rx.recv().unwrap().result;
         assert_eq!(
             result,
@@ -306,7 +298,7 @@ fn report_time_test_template(report_time: bool) -> Option<TestExecTime> {
 
     let test_opts = TestOpts { time_options, ..TestOpts::new() };
     let (tx, rx) = channel();
-    run_test(&test_opts, false, TestId(0), desc, RunStrategy::InProcess, tx, Concurrent::No);
+    run_test(&test_opts, false, TestId(0), desc, RunStrategy::InProcess, tx);
     let exec_time = rx.recv().unwrap().exec_time;
     exec_time
 }
@@ -345,7 +337,7 @@ fn time_test_failure_template(test_type: TestType) -> TestResult {
 
     let test_opts = TestOpts { time_options: Some(time_options), ..TestOpts::new() };
     let (tx, rx) = channel();
-    run_test(&test_opts, false, TestId(0), desc, RunStrategy::InProcess, tx, Concurrent::No);
+    run_test(&test_opts, false, TestId(0), desc, RunStrategy::InProcess, tx);
     let result = rx.recv().unwrap().result;
 
     result
diff --git a/library/unwind/Cargo.toml b/library/unwind/Cargo.toml
index 69fce8d7795c..eab2717c4523 100644
--- a/library/unwind/Cargo.toml
+++ b/library/unwind/Cargo.toml
@@ -17,10 +17,10 @@ doc = false
 core = { path = "../core" }
 libc = { version = "0.2.79", features = ['rustc-dep-of-std'], default-features = false }
 compiler_builtins = "0.1.0"
-cfg-if = "0.1.8"
+cfg-if = "1.0"
 
 [build-dependencies]
-cc = "1.0.69"
+cc = "1.0.76"
 
 [features]
 
diff --git a/library/unwind/build.rs b/library/unwind/build.rs
index 31af390253b6..5c3c02fb6ada 100644
--- a/library/unwind/build.rs
+++ b/library/unwind/build.rs
@@ -21,29 +21,5 @@ fn main() {
         if has_unwind {
             println!("cargo:rustc-cfg=feature=\"system-llvm-libunwind\"");
         }
-    } else if target.contains("freebsd") {
-        println!("cargo:rustc-link-lib=gcc_s");
-    } else if target.contains("netbsd") {
-        println!("cargo:rustc-link-lib=gcc_s");
-    } else if target.contains("openbsd") {
-        if target.contains("sparc64") {
-            println!("cargo:rustc-link-lib=gcc");
-        } else {
-            println!("cargo:rustc-link-lib=c++abi");
-        }
-    } else if target.contains("solaris") {
-        println!("cargo:rustc-link-lib=gcc_s");
-    } else if target.contains("illumos") {
-        println!("cargo:rustc-link-lib=gcc_s");
-    } else if target.contains("dragonfly") {
-        println!("cargo:rustc-link-lib=gcc_pic");
-    } else if target.ends_with("pc-windows-gnu") {
-        // This is handled in the target spec with late_link_args_[static|dynamic]
-    } else if target.contains("uwp-windows-gnu") {
-        println!("cargo:rustc-link-lib=unwind");
-    } else if target.contains("haiku") {
-        println!("cargo:rustc-link-lib=gcc_s");
-    } else if target.contains("redox") {
-        // redox is handled in lib.rs
     }
 }
diff --git a/library/unwind/src/lib.rs b/library/unwind/src/lib.rs
index 46fe50cb9453..3753071d5f0c 100644
--- a/library/unwind/src/lib.rs
+++ b/library/unwind/src/lib.rs
@@ -15,7 +15,6 @@ cfg_if::cfg_if! {
         target_os = "espidf",
     ))] {
         // These "unix" family members do not have unwinder.
-        // Note this also matches x86_64-unknown-none-linuxkernel.
     } else if #[cfg(any(
         unix,
         windows,
@@ -105,6 +104,26 @@ extern "C" {}
 #[link(name = "unwind", kind = "static", modifiers = "-bundle")]
 extern "C" {}
 
-#[cfg(all(target_os = "windows", target_env = "gnu", target_abi = "llvm"))]
-#[link(name = "unwind", kind = "static", modifiers = "-bundle")]
+#[cfg(any(target_os = "freebsd", target_os = "netbsd"))]
+#[link(name = "gcc_s")]
+extern "C" {}
+
+#[cfg(all(target_os = "openbsd", target_arch = "sparc64"))]
+#[link(name = "gcc")]
+extern "C" {}
+
+#[cfg(all(target_os = "openbsd", not(target_arch = "sparc64")))]
+#[link(name = "c++abi")]
+extern "C" {}
+
+#[cfg(any(target_os = "solaris", target_os = "illumos"))]
+#[link(name = "gcc_s")]
+extern "C" {}
+
+#[cfg(target_os = "dragonfly")]
+#[link(name = "gcc_pic")]
+extern "C" {}
+
+#[cfg(target_os = "haiku")]
+#[link(name = "gcc_s")]
 extern "C" {}
diff --git a/library/unwind/src/libunwind.rs b/library/unwind/src/libunwind.rs
index a5b6193b086f..15500f7fd354 100644
--- a/library/unwind/src/libunwind.rs
+++ b/library/unwind/src/libunwind.rs
@@ -36,9 +36,12 @@ pub const unwinder_private_data_size: usize = 20;
 #[cfg(all(target_arch = "arm", any(target_os = "ios", target_os = "watchos")))]
 pub const unwinder_private_data_size: usize = 5;
 
-#[cfg(all(target_arch = "aarch64", target_pointer_width = "64"))]
+#[cfg(all(target_arch = "aarch64", target_pointer_width = "64", not(target_os = "windows")))]
 pub const unwinder_private_data_size: usize = 2;
 
+#[cfg(all(target_arch = "aarch64", target_pointer_width = "64", target_os = "windows"))]
+pub const unwinder_private_data_size: usize = 6;
+
 #[cfg(all(target_arch = "aarch64", target_pointer_width = "32"))]
 pub const unwinder_private_data_size: usize = 5;
 
@@ -90,7 +93,10 @@ pub type _Unwind_Exception_Cleanup_Fn =
 // rustc_codegen_ssa::src::back::symbol_export, rustc_middle::middle::exported_symbols
 // and RFC 2841
 #[cfg_attr(
-    all(feature = "llvm-libunwind", any(target_os = "fuchsia", target_os = "linux")),
+    any(
+        all(feature = "llvm-libunwind", any(target_os = "fuchsia", target_os = "linux")),
+        all(target_os = "windows", target_env = "gnu", target_abi = "llvm")
+    ),
     link(name = "unwind", kind = "static", modifiers = "-bundle")
 )]
 extern "C-unwind" {
diff --git a/src/bootstrap/Cargo.lock b/src/bootstrap/Cargo.lock
index baecca44cd98..e1a108cea957 100644
--- a/src/bootstrap/Cargo.lock
+++ b/src/bootstrap/Cargo.lock
@@ -224,13 +224,13 @@ dependencies = [
 
 [[package]]
 name = "fd-lock"
-version = "3.0.6"
+version = "3.0.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e11dcc7e4d79a8c89b9ab4c6f5c30b1fc4a83c420792da3542fd31179ed5f517"
+checksum = "0c93a581058d957dc4176875aad04f82f81613e6611d64aa1a9c755bdfb16711"
 dependencies = [
  "cfg-if",
  "rustix",
- "windows-sys",
+ "windows-sys 0.42.0",
 ]
 
 [[package]]
@@ -528,7 +528,7 @@ dependencies = [
  "io-lifetimes",
  "libc",
  "linux-raw-sys",
- "windows-sys",
+ "windows-sys 0.36.1",
 ]
 
 [[package]]
@@ -721,43 +721,100 @@ version = "0.36.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ea04155a16a59f9eab786fe12a4a450e75cdb175f9e0d80da1e17db09f55b8d2"
 dependencies = [
- "windows_aarch64_msvc",
- "windows_i686_gnu",
- "windows_i686_msvc",
- "windows_x86_64_gnu",
- "windows_x86_64_msvc",
+ "windows_aarch64_msvc 0.36.1",
+ "windows_i686_gnu 0.36.1",
+ "windows_i686_msvc 0.36.1",
+ "windows_x86_64_gnu 0.36.1",
+ "windows_x86_64_msvc 0.36.1",
 ]
 
+[[package]]
+name = "windows-sys"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5a3e1820f08b8513f676f7ab6c1f99ff312fb97b553d30ff4dd86f9f15728aa7"
+dependencies = [
+ "windows_aarch64_gnullvm",
+ "windows_aarch64_msvc 0.42.0",
+ "windows_i686_gnu 0.42.0",
+ "windows_i686_msvc 0.42.0",
+ "windows_x86_64_gnu 0.42.0",
+ "windows_x86_64_gnullvm",
+ "windows_x86_64_msvc 0.42.0",
+]
+
+[[package]]
+name = "windows_aarch64_gnullvm"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "41d2aa71f6f0cbe00ae5167d90ef3cfe66527d6f613ca78ac8024c3ccab9a19e"
+
 [[package]]
 name = "windows_aarch64_msvc"
 version = "0.36.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9bb8c3fd39ade2d67e9874ac4f3db21f0d710bee00fe7cab16949ec184eeaa47"
 
+[[package]]
+name = "windows_aarch64_msvc"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dd0f252f5a35cac83d6311b2e795981f5ee6e67eb1f9a7f64eb4500fbc4dcdb4"
+
 [[package]]
 name = "windows_i686_gnu"
 version = "0.36.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "180e6ccf01daf4c426b846dfc66db1fc518f074baa793aa7d9b9aaeffad6a3b6"
 
+[[package]]
+name = "windows_i686_gnu"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fbeae19f6716841636c28d695375df17562ca208b2b7d0dc47635a50ae6c5de7"
+
 [[package]]
 name = "windows_i686_msvc"
 version = "0.36.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e2e7917148b2812d1eeafaeb22a97e4813dfa60a3f8f78ebe204bcc88f12f024"
 
+[[package]]
+name = "windows_i686_msvc"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "84c12f65daa39dd2babe6e442988fc329d6243fdce47d7d2d155b8d874862246"
+
 [[package]]
 name = "windows_x86_64_gnu"
 version = "0.36.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4dcd171b8776c41b97521e5da127a2d86ad280114807d0b2ab1e462bc764d9e1"
 
+[[package]]
+name = "windows_x86_64_gnu"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bf7b1b21b5362cbc318f686150e5bcea75ecedc74dd157d874d754a2ca44b0ed"
+
+[[package]]
+name = "windows_x86_64_gnullvm"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "09d525d2ba30eeb3297665bd434a54297e4170c7f1a44cad4ef58095b4cd2028"
+
 [[package]]
 name = "windows_x86_64_msvc"
 version = "0.36.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c811ca4a8c853ef420abd8592ba53ddbbac90410fab6903b3e79972a631f7680"
 
+[[package]]
+name = "windows_x86_64_msvc"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f40009d85759725a34da6d89a94e63d7bdc50a862acf0dbc7c8e488f1edcb6f5"
+
 [[package]]
 name = "xattr"
 version = "0.2.3"
diff --git a/src/bootstrap/Cargo.toml b/src/bootstrap/Cargo.toml
index 95e711737738..f74738437ea3 100644
--- a/src/bootstrap/Cargo.toml
+++ b/src/bootstrap/Cargo.toml
@@ -36,7 +36,7 @@ test = false
 
 [dependencies]
 cmake = "0.1.38"
-fd-lock = "3.0.6"
+fd-lock = "3.0.7"
 filetime = "0.2"
 getopts = "0.2.19"
 cc = "1.0.69"
diff --git a/src/bootstrap/bin/main.rs b/src/bootstrap/bin/main.rs
index 9b4861ccd95f..be69f819c642 100644
--- a/src/bootstrap/bin/main.rs
+++ b/src/bootstrap/bin/main.rs
@@ -35,7 +35,7 @@ fn main() {
 
     // NOTE: Since `./configure` generates a `config.toml`, distro maintainers will see the
     // changelog warning, not the `x.py setup` message.
-    let suggest_setup = !config.config.exists() && !matches!(config.cmd, Subcommand::Setup { .. });
+    let suggest_setup = config.config.is_none() && !matches!(config.cmd, Subcommand::Setup { .. });
     if suggest_setup {
         println!("warning: you have not made a `config.toml`");
         println!(
diff --git a/src/bootstrap/bin/rustdoc.rs b/src/bootstrap/bin/rustdoc.rs
index e69cab956c50..23828f4758d6 100644
--- a/src/bootstrap/bin/rustdoc.rs
+++ b/src/bootstrap/bin/rustdoc.rs
@@ -55,13 +55,9 @@ fn main() {
         arg.push(&linker);
         cmd.arg(arg);
     }
-    if env::var_os("RUSTDOC_FUSE_LD_LLD").is_some() {
+    if let Ok(no_threads) = env::var("RUSTDOC_LLD_NO_THREADS") {
         cmd.arg("-Clink-arg=-fuse-ld=lld");
-        if cfg!(windows) {
-            cmd.arg("-Clink-arg=-Wl,/threads:1");
-        } else {
-            cmd.arg("-Clink-arg=-Wl,--threads=1");
-        }
+        cmd.arg(format!("-Clink-arg=-Wl,{}", no_threads));
     }
     // Cargo doesn't pass RUSTDOCFLAGS to proc_macros:
     // https://github.com/rust-lang/cargo/issues/4423
diff --git a/src/bootstrap/builder.rs b/src/bootstrap/builder.rs
index 8b144f146357..8d999302a6d7 100644
--- a/src/bootstrap/builder.rs
+++ b/src/bootstrap/builder.rs
@@ -2,14 +2,13 @@ use std::any::{type_name, Any};
 use std::cell::{Cell, RefCell};
 use std::collections::BTreeSet;
 use std::env;
-use std::ffi::{OsStr, OsString};
+use std::ffi::OsStr;
 use std::fmt::{Debug, Write};
-use std::fs::{self, File};
+use std::fs::{self};
 use std::hash::Hash;
-use std::io::{BufRead, BufReader, ErrorKind};
 use std::ops::Deref;
 use std::path::{Component, Path, PathBuf};
-use std::process::{Command, Stdio};
+use std::process::Command;
 use std::time::{Duration, Instant};
 
 use crate::cache::{Cache, Interned, INTERNER};
@@ -24,14 +23,12 @@ use crate::test;
 use crate::tool::{self, SourceType};
 use crate::util::{self, add_dylib_path, add_link_lib_path, exe, libdir, output, t};
 use crate::EXTRA_CHECK_CFGS;
-use crate::{check, Config};
-use crate::{compile, Crate};
+use crate::{check, compile, Crate};
 use crate::{Build, CLang, DocTests, GitRepo, Mode};
 
 pub use crate::Compiler;
 // FIXME: replace with std::lazy after it gets stabilized and reaches beta
-use once_cell::sync::{Lazy, OnceCell};
-use xz2::bufread::XzDecoder;
+use once_cell::sync::Lazy;
 
 pub struct Builder<'a> {
     pub build: &'a Build,
@@ -621,6 +618,8 @@ impl<'a> Builder<'a> {
                 check::CodegenBackend,
                 check::Clippy,
                 check::Miri,
+                check::CargoMiri,
+                check::MiroptTestTools,
                 check::Rls,
                 check::RustAnalyzer,
                 check::Rustfmt,
@@ -753,6 +752,7 @@ impl<'a> Builder<'a> {
                 run::BuildManifest,
                 run::BumpStage0,
                 run::ReplaceVersionPlaceholder,
+                run::Miri,
             ),
             // These commands either don't use paths, or they're special-cased in Build::build()
             Kind::Clean | Kind::Format | Kind::Setup => vec![],
@@ -816,7 +816,7 @@ impl<'a> Builder<'a> {
             Subcommand::Bench { ref paths, .. } => (Kind::Bench, &paths[..]),
             Subcommand::Dist { ref paths } => (Kind::Dist, &paths[..]),
             Subcommand::Install { ref paths } => (Kind::Install, &paths[..]),
-            Subcommand::Run { ref paths } => (Kind::Run, &paths[..]),
+            Subcommand::Run { ref paths, .. } => (Kind::Run, &paths[..]),
             Subcommand::Format { .. } => (Kind::Format, &[][..]),
             Subcommand::Clean { .. } | Subcommand::Setup { .. } => {
                 panic!()
@@ -850,241 +850,6 @@ impl<'a> Builder<'a> {
         StepDescription::run(v, self, paths);
     }
 
-    /// Modifies the interpreter section of 'fname' to fix the dynamic linker,
-    /// or the RPATH section, to fix the dynamic library search path
-    ///
-    /// This is only required on NixOS and uses the PatchELF utility to
-    /// change the interpreter/RPATH of ELF executables.
-    ///
-    /// Please see https://nixos.org/patchelf.html for more information
-    pub(crate) fn fix_bin_or_dylib(&self, fname: &Path) {
-        // FIXME: cache NixOS detection?
-        match Command::new("uname").arg("-s").stderr(Stdio::inherit()).output() {
-            Err(_) => return,
-            Ok(output) if !output.status.success() => return,
-            Ok(output) => {
-                let mut s = output.stdout;
-                if s.last() == Some(&b'\n') {
-                    s.pop();
-                }
-                if s != b"Linux" {
-                    return;
-                }
-            }
-        }
-
-        // If the user has asked binaries to be patched for Nix, then
-        // don't check for NixOS or `/lib`, just continue to the patching.
-        // NOTE: this intentionally comes after the Linux check:
-        // - patchelf only works with ELF files, so no need to run it on Mac or Windows
-        // - On other Unix systems, there is no stable syscall interface, so Nix doesn't manage the global libc.
-        if !self.config.patch_binaries_for_nix {
-            // Use `/etc/os-release` instead of `/etc/NIXOS`.
-            // The latter one does not exist on NixOS when using tmpfs as root.
-            const NIX_IDS: &[&str] = &["ID=nixos", "ID='nixos'", "ID=\"nixos\""];
-            let os_release = match File::open("/etc/os-release") {
-                Err(e) if e.kind() == ErrorKind::NotFound => return,
-                Err(e) => panic!("failed to access /etc/os-release: {}", e),
-                Ok(f) => f,
-            };
-            if !BufReader::new(os_release).lines().any(|l| NIX_IDS.contains(&t!(l).trim())) {
-                return;
-            }
-            if Path::new("/lib").exists() {
-                return;
-            }
-        }
-
-        // At this point we're pretty sure the user is running NixOS or using Nix
-        println!("info: you seem to be using Nix. Attempting to patch {}", fname.display());
-
-        // Only build `.nix-deps` once.
-        static NIX_DEPS_DIR: OnceCell<PathBuf> = OnceCell::new();
-        let mut nix_build_succeeded = true;
-        let nix_deps_dir = NIX_DEPS_DIR.get_or_init(|| {
-            // Run `nix-build` to "build" each dependency (which will likely reuse
-            // the existing `/nix/store` copy, or at most download a pre-built copy).
-            //
-            // Importantly, we create a gc-root called `.nix-deps` in the `build/`
-            // directory, but still reference the actual `/nix/store` path in the rpath
-            // as it makes it significantly more robust against changes to the location of
-            // the `.nix-deps` location.
-            //
-            // bintools: Needed for the path of `ld-linux.so` (via `nix-support/dynamic-linker`).
-            // zlib: Needed as a system dependency of `libLLVM-*.so`.
-            // patchelf: Needed for patching ELF binaries (see doc comment above).
-            let nix_deps_dir = self.out.join(".nix-deps");
-            const NIX_EXPR: &str = "
-            with (import <nixpkgs> {});
-            symlinkJoin {
-                name = \"rust-stage0-dependencies\";
-                paths = [
-                    zlib
-                    patchelf
-                    stdenv.cc.bintools
-                ];
-            }
-            ";
-            nix_build_succeeded = self.try_run(Command::new("nix-build").args(&[
-                Path::new("-E"),
-                Path::new(NIX_EXPR),
-                Path::new("-o"),
-                &nix_deps_dir,
-            ]));
-            nix_deps_dir
-        });
-        if !nix_build_succeeded {
-            return;
-        }
-
-        let mut patchelf = Command::new(nix_deps_dir.join("bin/patchelf"));
-        let rpath_entries = {
-            // ORIGIN is a relative default, all binary and dynamic libraries we ship
-            // appear to have this (even when `../lib` is redundant).
-            // NOTE: there are only two paths here, delimited by a `:`
-            let mut entries = OsString::from("$ORIGIN/../lib:");
-            entries.push(t!(fs::canonicalize(nix_deps_dir)));
-            entries.push("/lib");
-            entries
-        };
-        patchelf.args(&[OsString::from("--set-rpath"), rpath_entries]);
-        if !fname.extension().map_or(false, |ext| ext == "so") {
-            // Finally, set the correct .interp for binaries
-            let dynamic_linker_path = nix_deps_dir.join("nix-support/dynamic-linker");
-            // FIXME: can we support utf8 here? `args` doesn't accept Vec<u8>, only OsString ...
-            let dynamic_linker = t!(String::from_utf8(t!(fs::read(dynamic_linker_path))));
-            patchelf.args(&["--set-interpreter", dynamic_linker.trim_end()]);
-        }
-
-        self.try_run(patchelf.arg(fname));
-    }
-
-    pub(crate) fn download_component(&self, url: &str, dest_path: &Path, help_on_error: &str) {
-        self.verbose(&format!("download {url}"));
-        // Use a temporary file in case we crash while downloading, to avoid a corrupt download in cache/.
-        let tempfile = self.tempdir().join(dest_path.file_name().unwrap());
-        // While bootstrap itself only supports http and https downloads, downstream forks might
-        // need to download components from other protocols. The match allows them adding more
-        // protocols without worrying about merge conflicts if we change the HTTP implementation.
-        match url.split_once("://").map(|(proto, _)| proto) {
-            Some("http") | Some("https") => {
-                self.download_http_with_retries(&tempfile, url, help_on_error)
-            }
-            Some(other) => panic!("unsupported protocol {other} in {url}"),
-            None => panic!("no protocol in {url}"),
-        }
-        t!(std::fs::rename(&tempfile, dest_path));
-    }
-
-    fn download_http_with_retries(&self, tempfile: &Path, url: &str, help_on_error: &str) {
-        println!("downloading {}", url);
-        // Try curl. If that fails and we are on windows, fallback to PowerShell.
-        let mut curl = Command::new("curl");
-        curl.args(&[
-            "-#",
-            "-y",
-            "30",
-            "-Y",
-            "10", // timeout if speed is < 10 bytes/sec for > 30 seconds
-            "--connect-timeout",
-            "30", // timeout if cannot connect within 30 seconds
-            "--retry",
-            "3",
-            "-Sf",
-            "-o",
-        ]);
-        curl.arg(tempfile);
-        curl.arg(url);
-        if !self.check_run(&mut curl) {
-            if self.build.build.contains("windows-msvc") {
-                println!("Fallback to PowerShell");
-                for _ in 0..3 {
-                    if self.try_run(Command::new("PowerShell.exe").args(&[
-                        "/nologo",
-                        "-Command",
-                        "[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12;",
-                        &format!(
-                            "(New-Object System.Net.WebClient).DownloadFile('{}', '{}')",
-                            url, tempfile.to_str().expect("invalid UTF-8 not supported with powershell downloads"),
-                        ),
-                    ])) {
-                        return;
-                    }
-                    println!("\nspurious failure, trying again");
-                }
-            }
-            if !help_on_error.is_empty() {
-                eprintln!("{}", help_on_error);
-            }
-            crate::detail_exit(1);
-        }
-    }
-
-    pub(crate) fn unpack(&self, tarball: &Path, dst: &Path, pattern: &str) {
-        println!("extracting {} to {}", tarball.display(), dst.display());
-        if !dst.exists() {
-            t!(fs::create_dir_all(dst));
-        }
-
-        // `tarball` ends with `.tar.xz`; strip that suffix
-        // example: `rust-dev-nightly-x86_64-unknown-linux-gnu`
-        let uncompressed_filename =
-            Path::new(tarball.file_name().expect("missing tarball filename")).file_stem().unwrap();
-        let directory_prefix = Path::new(Path::new(uncompressed_filename).file_stem().unwrap());
-
-        // decompress the file
-        let data = t!(File::open(tarball));
-        let decompressor = XzDecoder::new(BufReader::new(data));
-
-        let mut tar = tar::Archive::new(decompressor);
-        for member in t!(tar.entries()) {
-            let mut member = t!(member);
-            let original_path = t!(member.path()).into_owned();
-            // skip the top-level directory
-            if original_path == directory_prefix {
-                continue;
-            }
-            let mut short_path = t!(original_path.strip_prefix(directory_prefix));
-            if !short_path.starts_with(pattern) {
-                continue;
-            }
-            short_path = t!(short_path.strip_prefix(pattern));
-            let dst_path = dst.join(short_path);
-            self.verbose(&format!("extracting {} to {}", original_path.display(), dst.display()));
-            if !t!(member.unpack_in(dst)) {
-                panic!("path traversal attack ??");
-            }
-            let src_path = dst.join(original_path);
-            if src_path.is_dir() && dst_path.exists() {
-                continue;
-            }
-            t!(fs::rename(src_path, dst_path));
-        }
-        t!(fs::remove_dir_all(dst.join(directory_prefix)));
-    }
-
-    /// Returns whether the SHA256 checksum of `path` matches `expected`.
-    pub(crate) fn verify(&self, path: &Path, expected: &str) -> bool {
-        use sha2::Digest;
-
-        self.verbose(&format!("verifying {}", path.display()));
-        let mut hasher = sha2::Sha256::new();
-        // FIXME: this is ok for rustfmt (4.1 MB large at time of writing), but it seems memory-intensive for rustc and larger components.
-        // Consider using streaming IO instead?
-        let contents = if self.config.dry_run { vec![] } else { t!(fs::read(path)) };
-        hasher.update(&contents);
-        let found = hex::encode(hasher.finalize().as_slice());
-        let verified = found == expected;
-        if !verified && !self.config.dry_run {
-            println!(
-                "invalid checksum: \n\
-                found:    {found}\n\
-                expected: {expected}",
-            );
-        }
-        return verified;
-    }
-
     /// Obtain a compiler at a given stage and for a given host. Explicitly does
     /// not take `Compiler` since all `Compiler` instances are meant to be
     /// obtained through this function, since it ensures that they are valid
@@ -1289,7 +1054,7 @@ impl<'a> Builder<'a> {
     /// Note that this returns `None` if LLVM is disabled, or if we're in a
     /// check build or dry-run, where there's no need to build all of LLVM.
     fn llvm_config(&self, target: TargetSelection) -> Option<PathBuf> {
-        if self.config.llvm_enabled() && self.kind != Kind::Check && !self.config.dry_run {
+        if self.config.llvm_enabled() && self.kind != Kind::Check && !self.config.dry_run() {
             let llvm_config = self.ensure(native::Llvm { target });
             if llvm_config.is_file() {
                 return Some(llvm_config);
@@ -1298,19 +1063,6 @@ impl<'a> Builder<'a> {
         None
     }
 
-    /// Convenience wrapper to allow `builder.llvm_link_shared()` instead of `builder.config.llvm_link_shared(&builder)`.
-    pub(crate) fn llvm_link_shared(&self) -> bool {
-        Config::llvm_link_shared(self)
-    }
-
-    pub(crate) fn download_rustc(&self) -> bool {
-        Config::download_rustc(self)
-    }
-
-    pub(crate) fn initial_rustfmt(&self) -> Option<PathBuf> {
-        Config::initial_rustfmt(self)
-    }
-
     /// Prepares an invocation of `cargo` to be run.
     ///
     /// This will create a `Command` that represents a pending execution of
@@ -1641,7 +1393,7 @@ impl<'a> Builder<'a> {
         //
         // Only clear out the directory if we're compiling std; otherwise, we
         // should let Cargo take care of things for us (via depdep info)
-        if !self.config.dry_run && mode == Mode::Std && cmd == "build" {
+        if !self.config.dry_run() && mode == Mode::Std && cmd == "build" {
             self.clear_if_dirty(&out_dir, &self.rustc(compiler));
         }
 
@@ -2139,7 +1891,7 @@ impl<'a> Builder<'a> {
             (out, dur - deps)
         };
 
-        if self.config.print_step_timings && !self.config.dry_run {
+        if self.config.print_step_timings && !self.config.dry_run() {
             let step_string = format!("{:?}", step);
             let brace_index = step_string.find("{").unwrap_or(0);
             let type_string = type_name::<S>();
@@ -2205,6 +1957,24 @@ impl<'a> Builder<'a> {
 
         false
     }
+
+    pub(crate) fn maybe_open_in_browser<S: Step>(&self, path: impl AsRef<Path>) {
+        if self.was_invoked_explicitly::<S>(Kind::Doc) {
+            self.open_in_browser(path);
+        }
+    }
+
+    pub(crate) fn open_in_browser(&self, path: impl AsRef<Path>) {
+        if self.config.dry_run() || !self.config.cmd.open() {
+            return;
+        }
+
+        let path = path.as_ref();
+        self.info(&format!("Opening doc {}", path.display()));
+        if let Err(err) = opener::open(path) {
+            self.info(&format!("{}\n", err));
+        }
+    }
 }
 
 #[cfg(test)]
diff --git a/src/bootstrap/builder/tests.rs b/src/bootstrap/builder/tests.rs
index 88bbcc93d072..5f21d2b0067d 100644
--- a/src/bootstrap/builder/tests.rs
+++ b/src/bootstrap/builder/tests.rs
@@ -1,5 +1,5 @@
 use super::*;
-use crate::config::{Config, TargetSelection};
+use crate::config::{Config, DryRun, TargetSelection};
 use std::thread;
 
 fn configure(cmd: &str, host: &[&str], target: &[&str]) -> Config {
@@ -10,7 +10,7 @@ fn configure_with_args(cmd: &[String], host: &[&str], target: &[&str]) -> Config
     let mut config = Config::parse(cmd);
     // don't save toolstates
     config.save_toolstates = None;
-    config.dry_run = true;
+    config.dry_run = DryRun::SelfCheck;
 
     // Ignore most submodules, since we don't need them for a dry run.
     // But make sure to check out the `doc` and `rust-analyzer` submodules, since some steps need them
diff --git a/src/bootstrap/channel.rs b/src/bootstrap/channel.rs
index 258352a21a4a..eae81b9fc69c 100644
--- a/src/bootstrap/channel.rs
+++ b/src/bootstrap/channel.rs
@@ -13,8 +13,10 @@ use crate::util::output;
 use crate::util::t;
 use crate::Build;
 
+#[derive(Clone, Default)]
 pub enum GitInfo {
     /// This is not a git repository.
+    #[default]
     Absent,
     /// This is a git repository.
     /// If the info should be used (`ignore_git` is false), this will be
@@ -25,6 +27,7 @@ pub enum GitInfo {
     RecordedForTarball(Info),
 }
 
+#[derive(Clone)]
 pub struct Info {
     pub commit_date: String,
     pub sha: String,
diff --git a/src/bootstrap/check.rs b/src/bootstrap/check.rs
index 229851238f1d..2e1bd8d6d1f6 100644
--- a/src/bootstrap/check.rs
+++ b/src/bootstrap/check.rs
@@ -451,16 +451,16 @@ macro_rules! tool_check_step {
 }
 
 tool_check_step!(Rustdoc, "src/tools/rustdoc", "src/librustdoc", SourceType::InTree);
-// Clippy and Rustfmt are hybrids. They are external tools, but use a git subtree instead
+// Clippy, miri and Rustfmt are hybrids. They are external tools, but use a git subtree instead
 // of a submodule. Since the SourceType only drives the deny-warnings
 // behavior, treat it as in-tree so that any new warnings in clippy will be
 // rejected.
 tool_check_step!(Clippy, "src/tools/clippy", SourceType::InTree);
-// Miri on the other hand is treated as out of tree, since InTree also causes it to
-// be run as part of `check`, which can fail on platforms which libffi-sys has no support for.
-tool_check_step!(Miri, "src/tools/miri", SourceType::Submodule);
+tool_check_step!(Miri, "src/tools/miri", SourceType::InTree);
+tool_check_step!(CargoMiri, "src/tools/miri/cargo-miri", SourceType::InTree);
 tool_check_step!(Rls, "src/tools/rls", SourceType::InTree);
 tool_check_step!(Rustfmt, "src/tools/rustfmt", SourceType::InTree);
+tool_check_step!(MiroptTestTools, "src/tools/miropt-test-tools", SourceType::InTree);
 
 tool_check_step!(Bootstrap, "src/bootstrap", SourceType::InTree, false);
 
diff --git a/src/bootstrap/compile.rs b/src/bootstrap/compile.rs
index e02a10b81640..54906a4918bc 100644
--- a/src/bootstrap/compile.rs
+++ b/src/bootstrap/compile.rs
@@ -206,7 +206,6 @@ fn copy_third_party_objects(
     }
 
     if target == "x86_64-fortanix-unknown-sgx"
-        || target.contains("pc-windows-gnullvm")
         || builder.config.llvm_libunwind(target) == LlvmLibunwind::InTree
             && (target.contains("linux") || target.contains("fuchsia"))
     {
@@ -299,7 +298,9 @@ pub fn std_cargo(builder: &Builder<'_>, target: TargetSelection, stage: u32, car
 
     // Determine if we're going to compile in optimized C intrinsics to
     // the `compiler-builtins` crate. These intrinsics live in LLVM's
-    // `compiler-rt` repository.
+    // `compiler-rt` repository, but our `src/llvm-project` submodule isn't
+    // always checked out, so we need to conditionally look for this. (e.g. if
+    // an external LLVM is used we skip the LLVM submodule checkout).
     //
     // Note that this shouldn't affect the correctness of `compiler-builtins`,
     // but only its speed. Some intrinsics in C haven't been translated to Rust
@@ -310,15 +311,8 @@ pub fn std_cargo(builder: &Builder<'_>, target: TargetSelection, stage: u32, car
     // If `compiler-rt` is available ensure that the `c` feature of the
     // `compiler-builtins` crate is enabled and it's configured to learn where
     // `compiler-rt` is located.
-    let compiler_builtins_c_feature = if builder.config.optimized_compiler_builtins {
-        if !builder.is_rust_llvm(target) {
-            panic!(
-                "need a managed LLVM submodule for optimized intrinsics support; unset `llvm-config` or `optimized-compiler-builtins`"
-            );
-        }
-
-        builder.update_submodule(&Path::new("src").join("llvm-project"));
-        let compiler_builtins_root = builder.src.join("src/llvm-project/compiler-rt");
+    let compiler_builtins_root = builder.src.join("src/llvm-project/compiler-rt");
+    let compiler_builtins_c_feature = if compiler_builtins_root.exists() {
         // Note that `libprofiler_builtins/build.rs` also computes this so if
         // you're changing something here please also change that.
         cargo.env("RUST_COMPILER_RT_ROOT", &compiler_builtins_root);
@@ -452,7 +446,7 @@ fn copy_sanitizers(
 ) -> Vec<PathBuf> {
     let runtimes: Vec<native::SanitizerRuntime> = builder.ensure(native::Sanitizers { target });
 
-    if builder.config.dry_run {
+    if builder.config.dry_run() {
         return Vec::new();
     }
 
@@ -769,10 +763,10 @@ pub fn rustc_cargo_env(builder: &Builder<'_>, cargo: &mut Cargo, target: TargetS
 
     cargo.env("CFG_LIBDIR_RELATIVE", libdir_relative);
 
-    if let Some(ref ver_date) = builder.rust_info.commit_date() {
+    if let Some(ref ver_date) = builder.rust_info().commit_date() {
         cargo.env("CFG_VER_DATE", ver_date);
     }
-    if let Some(ref ver_hash) = builder.rust_info.sha() {
+    if let Some(ref ver_hash) = builder.rust_info().sha() {
         cargo.env("CFG_VER_HASH", ver_hash);
     }
     if !builder.unstable_features() {
@@ -991,7 +985,7 @@ impl Step for CodegenBackend {
             compiler.stage, backend, &compiler.host, target
         ));
         let files = run_cargo(builder, cargo, vec![], &tmp_stamp, vec![], false);
-        if builder.config.dry_run {
+        if builder.config.dry_run() {
             return;
         }
         let mut files = files.into_iter().filter(|f| {
@@ -1039,7 +1033,7 @@ fn copy_codegen_backends_to_sysroot(
     let dst = builder.sysroot_codegen_backends(target_compiler);
     t!(fs::create_dir_all(&dst), dst);
 
-    if builder.config.dry_run {
+    if builder.config.dry_run() {
         return;
     }
 
@@ -1337,7 +1331,7 @@ impl Step for Assemble {
 
         if builder.config.rust_codegen_backends.contains(&INTERNER.intern_str("llvm")) {
             let llvm_config_bin = builder.ensure(native::Llvm { target: target_compiler.host });
-            if !builder.config.dry_run {
+            if !builder.config.dry_run() {
                 let llvm_bin_dir = output(Command::new(llvm_config_bin).arg("--bindir"));
                 let llvm_bin_dir = Path::new(llvm_bin_dir.trim());
 
@@ -1407,7 +1401,7 @@ pub fn run_cargo(
     additional_target_deps: Vec<(PathBuf, DependencyType)>,
     is_check: bool,
 ) -> Vec<PathBuf> {
-    if builder.config.dry_run {
+    if builder.config.dry_run() {
         return Vec::new();
     }
 
@@ -1547,7 +1541,7 @@ pub fn stream_cargo(
     cb: &mut dyn FnMut(CargoMessage<'_>),
 ) -> bool {
     let mut cargo = Command::from(cargo);
-    if builder.config.dry_run {
+    if builder.config.dry_run() {
         return true;
     }
     // Instruct Cargo to give us json messages on stdout, critically leaving
diff --git a/src/bootstrap/config.rs b/src/bootstrap/config.rs
index a8c403675d82..af004aa50985 100644
--- a/src/bootstrap/config.rs
+++ b/src/bootstrap/config.rs
@@ -7,19 +7,18 @@ use std::cell::{Cell, RefCell};
 use std::cmp;
 use std::collections::{HashMap, HashSet};
 use std::env;
-use std::ffi::OsStr;
 use std::fmt;
 use std::fs;
 use std::path::{Path, PathBuf};
 use std::process::Command;
 use std::str::FromStr;
 
-use crate::builder::{Builder, TaskPath};
+use crate::builder::TaskPath;
 use crate::cache::{Interned, INTERNER};
-use crate::channel::GitInfo;
+use crate::channel::{self, GitInfo};
 pub use crate::flags::Subcommand;
 use crate::flags::{Color, Flags};
-use crate::util::{exe, output, program_out_of_date, t};
+use crate::util::{exe, output, t};
 use once_cell::sync::OnceCell;
 use serde::{Deserialize, Deserializer};
 
@@ -33,6 +32,17 @@ macro_rules! check_ci_llvm {
     };
 }
 
+#[derive(Clone, Default)]
+pub enum DryRun {
+    /// This isn't a dry run.
+    #[default]
+    Disabled,
+    /// This is a dry run enabled by bootstrap itself, so it can verify that no work is done.
+    SelfCheck,
+    /// This is a dry run enabled by the `--dry-run` flag.
+    UserSelected,
+}
+
 /// Global configuration for the entire build and/or bootstrap.
 ///
 /// This structure is derived from a combination of both `config.toml` and
@@ -73,8 +83,6 @@ pub struct Config {
     pub color: Color,
     pub patch_binaries_for_nix: bool,
     pub stage0_metadata: Stage0Metadata,
-    /// Whether to use the `c` feature of the `compiler_builtins` crate.
-    pub optimized_compiler_builtins: bool,
 
     pub on_fail: Option<String>,
     pub stage: u32,
@@ -82,11 +90,11 @@ pub struct Config {
     pub keep_stage_std: Vec<u32>,
     pub src: PathBuf,
     /// defaults to `config.toml`
-    pub config: PathBuf,
+    pub config: Option<PathBuf>,
     pub jobs: Option<u32>,
     pub cmd: Subcommand,
     pub incremental: bool,
-    pub dry_run: bool,
+    pub dry_run: DryRun,
     /// `None` if we shouldn't download CI compiler artifacts, or the commit to download if we should.
     #[cfg(not(test))]
     download_rustc_commit: Option<String>,
@@ -215,6 +223,7 @@ pub struct Config {
     #[cfg(test)]
     pub initial_rustfmt: RefCell<RustfmtState>,
     pub out: PathBuf,
+    pub rust_info: channel::GitInfo,
 }
 
 #[derive(Default, Deserialize)]
@@ -624,7 +633,6 @@ define_config! {
         bench_stage: Option<u32> = "bench-stage",
         patch_binaries_for_nix: Option<bool> = "patch-binaries-for-nix",
         metrics: Option<bool> = "metrics",
-        optimized_compiler_builtins: Option<bool> = "optimized-compiler-builtins",
     }
 }
 
@@ -784,7 +792,7 @@ impl Config {
         config.llvm_optimize = true;
         config.ninja_in_file = true;
         config.llvm_version_check = true;
-        config.llvm_static_stdcpp = true;
+        config.llvm_static_stdcpp = false;
         config.backtrace = true;
         config.rust_optimize = true;
         config.rust_optimize_tests = true;
@@ -823,7 +831,7 @@ impl Config {
         config.jobs = flags.jobs.map(threads_from_config);
         config.cmd = flags.cmd;
         config.incremental = flags.incremental;
-        config.dry_run = flags.dry_run;
+        config.dry_run = if flags.dry_run { DryRun::UserSelected } else { DryRun::Disabled };
         config.keep_stage = flags.keep_stage;
         config.keep_stage_std = flags.keep_stage_std;
         config.color = flags.color;
@@ -929,8 +937,10 @@ impl Config {
         // Give a hard error if `--config` or `RUST_BOOTSTRAP_CONFIG` are set to a missing path,
         // but not if `config.toml` hasn't been created.
         let mut toml = if !using_default_path || toml_path.exists() {
+            config.config = Some(toml_path.clone());
             get_toml(&toml_path)
         } else {
+            config.config = None;
             TomlConfig::default()
         };
 
@@ -945,7 +955,6 @@ impl Config {
         }
 
         config.changelog_seen = toml.changelog_seen;
-        config.config = toml_path;
 
         let build = toml.build.unwrap_or_default();
 
@@ -967,7 +976,7 @@ impl Config {
             .unwrap_or_else(|| config.out.join(config.build.triple).join("stage0/bin/cargo"));
 
         // NOTE: it's important this comes *after* we set `initial_rustc` just above.
-        if config.dry_run {
+        if config.dry_run() {
             let dir = config.out.join("tmp-dry-run");
             t!(fs::create_dir_all(&dir));
             config.out = dir;
@@ -1013,7 +1022,6 @@ impl Config {
         set(&mut config.print_step_timings, build.print_step_timings);
         set(&mut config.print_step_rusage, build.print_step_rusage);
         set(&mut config.patch_binaries_for_nix, build.patch_binaries_for_nix);
-        set(&mut config.optimized_compiler_builtins, build.optimized_compiler_builtins);
 
         config.verbose = cmp::max(config.verbose, flags.verbose);
 
@@ -1196,7 +1204,7 @@ impl Config {
             config.rust_codegen_units_std = rust.codegen_units_std.map(threads_from_config);
             config.rust_profile_use = flags.rust_profile_use.or(rust.profile_use);
             config.rust_profile_generate = flags.rust_profile_generate.or(rust.profile_generate);
-            config.download_rustc_commit = download_ci_rustc_commit(&config, rust.download_rustc);
+            config.download_rustc_commit = config.download_ci_rustc_commit(rust.download_rustc);
 
             config.rust_lto = rust
                 .lto
@@ -1318,6 +1326,7 @@ impl Config {
 
         let default = config.channel == "dev";
         config.ignore_git = ignore_git.unwrap_or(default);
+        config.rust_info = GitInfo::new(config.ignore_git, &config.src);
 
         let download_rustc = config.download_rustc_commit.is_some();
         // See https://github.com/rust-lang/compiler-team/issues/326
@@ -1375,6 +1384,13 @@ impl Config {
         config
     }
 
+    pub(crate) fn dry_run(&self) -> bool {
+        match self.dry_run {
+            DryRun::Disabled => false,
+            DryRun::SelfCheck | DryRun::UserSelected => true,
+        }
+    }
+
     /// A git invocation which runs inside the source directory.
     ///
     /// Use this rather than `Command::new("git")` in order to support out-of-tree builds.
@@ -1384,21 +1400,46 @@ impl Config {
         git
     }
 
-    pub(crate) fn artifact_channel(&self, builder: &Builder<'_>, commit: &str) -> String {
-        if builder.rust_info.is_managed_git_subrepository() {
+    /// Bootstrap embeds a version number into the name of shared libraries it uploads in CI.
+    /// Return the version it would have used for the given commit.
+    pub(crate) fn artifact_version_part(&self, commit: &str) -> String {
+        let (channel, version) = if self.rust_info.is_managed_git_subrepository() {
             let mut channel = self.git();
             channel.arg("show").arg(format!("{}:src/ci/channel", commit));
             let channel = output(&mut channel);
-            channel.trim().to_owned()
-        } else if let Ok(channel) = fs::read_to_string(builder.src.join("src/ci/channel")) {
-            channel.trim().to_owned()
+            let mut version = self.git();
+            version.arg("show").arg(format!("{}:src/version", commit));
+            let version = output(&mut version);
+            (channel.trim().to_owned(), version.trim().to_owned())
         } else {
-            let src = builder.src.display();
-            eprintln!("error: failed to determine artifact channel");
-            eprintln!(
-                "help: either use git or ensure that {src}/src/ci/channel contains the name of the channel to use"
-            );
-            panic!();
+            let channel = fs::read_to_string(self.src.join("src/ci/channel"));
+            let version = fs::read_to_string(self.src.join("src/version"));
+            match (channel, version) {
+                (Ok(channel), Ok(version)) => {
+                    (channel.trim().to_owned(), version.trim().to_owned())
+                }
+                (channel, version) => {
+                    let src = self.src.display();
+                    eprintln!("error: failed to determine artifact channel and/or version");
+                    eprintln!(
+                        "help: consider using a git checkout or ensure these files are readable"
+                    );
+                    if let Err(channel) = channel {
+                        eprintln!("reading {}/src/ci/channel failed: {:?}", src, channel);
+                    }
+                    if let Err(version) = version {
+                        eprintln!("reading {}/src/version failed: {:?}", src, version);
+                    }
+                    panic!();
+                }
+            }
+        };
+
+        match channel.as_str() {
+            "stable" => version,
+            "beta" => channel,
+            "nightly" => channel,
+            other => unreachable!("{:?} is not recognized as a valid channel", other),
         }
     }
 
@@ -1437,17 +1478,17 @@ impl Config {
     ///
     /// If `false`, llvm should be linked statically.
     /// This is computed on demand since LLVM might have to first be downloaded from CI.
-    pub(crate) fn llvm_link_shared(builder: &Builder<'_>) -> bool {
-        let mut opt = builder.config.llvm_link_shared.get();
-        if opt.is_none() && builder.config.dry_run {
+    pub(crate) fn llvm_link_shared(&self) -> bool {
+        let mut opt = self.llvm_link_shared.get();
+        if opt.is_none() && self.dry_run() {
             // just assume static for now - dynamic linking isn't supported on all platforms
             return false;
         }
 
         let llvm_link_shared = *opt.get_or_insert_with(|| {
-            if builder.config.llvm_from_ci {
-                crate::native::maybe_download_ci_llvm(builder);
-                let ci_llvm = builder.config.ci_llvm_root();
+            if self.llvm_from_ci {
+                self.maybe_download_ci_llvm();
+                let ci_llvm = self.ci_llvm_root();
                 let link_type = t!(
                     std::fs::read_to_string(ci_llvm.join("link-type.txt")),
                     format!("CI llvm missing: {}", ci_llvm.display())
@@ -1459,36 +1500,36 @@ impl Config {
                 false
             }
         });
-        builder.config.llvm_link_shared.set(opt);
+        self.llvm_link_shared.set(opt);
         llvm_link_shared
     }
 
     /// Return whether we will use a downloaded, pre-compiled version of rustc, or just build from source.
-    pub(crate) fn download_rustc(builder: &Builder<'_>) -> bool {
+    pub(crate) fn download_rustc(&self) -> bool {
         static DOWNLOAD_RUSTC: OnceCell<bool> = OnceCell::new();
-        if builder.config.dry_run && DOWNLOAD_RUSTC.get().is_none() {
+        if self.dry_run() && DOWNLOAD_RUSTC.get().is_none() {
             // avoid trying to actually download the commit
             return false;
         }
 
-        *DOWNLOAD_RUSTC.get_or_init(|| match &builder.config.download_rustc_commit {
+        *DOWNLOAD_RUSTC.get_or_init(|| match &self.download_rustc_commit {
             None => false,
             Some(commit) => {
-                download_ci_rustc(builder, commit);
+                self.download_ci_rustc(commit);
                 true
             }
         })
     }
 
-    pub(crate) fn initial_rustfmt(builder: &Builder<'_>) -> Option<PathBuf> {
-        match &mut *builder.config.initial_rustfmt.borrow_mut() {
+    pub(crate) fn initial_rustfmt(&self) -> Option<PathBuf> {
+        match &mut *self.initial_rustfmt.borrow_mut() {
             RustfmtState::SystemToolchain(p) | RustfmtState::Downloaded(p) => Some(p.clone()),
             RustfmtState::Unavailable => None,
             r @ RustfmtState::LazyEvaluated => {
-                if builder.config.dry_run {
+                if self.dry_run() {
                     return Some(PathBuf::new());
                 }
-                let path = maybe_download_rustfmt(builder);
+                let path = self.maybe_download_rustfmt();
                 *r = if let Some(p) = &path {
                     RustfmtState::Downloaded(p.clone())
                 } else {
@@ -1499,8 +1540,10 @@ impl Config {
         }
     }
 
-    pub fn verbose(&self) -> bool {
-        self.verbose > 0
+    pub fn verbose(&self, msg: &str) {
+        if self.verbose > 0 {
+            println!("{}", msg);
+        }
     }
 
     pub fn sanitizers_enabled(&self, target: TargetSelection) -> bool {
@@ -1538,6 +1581,66 @@ impl Config {
     pub fn submodules(&self, rust_info: &GitInfo) -> bool {
         self.submodules.unwrap_or(rust_info.is_managed_git_subrepository())
     }
+
+    /// Returns the commit to download, or `None` if we shouldn't download CI artifacts.
+    fn download_ci_rustc_commit(&self, download_rustc: Option<StringOrBool>) -> Option<String> {
+        // If `download-rustc` is not set, default to rebuilding.
+        let if_unchanged = match download_rustc {
+            None | Some(StringOrBool::Bool(false)) => return None,
+            Some(StringOrBool::Bool(true)) => false,
+            Some(StringOrBool::String(s)) if s == "if-unchanged" => true,
+            Some(StringOrBool::String(other)) => {
+                panic!("unrecognized option for download-rustc: {}", other)
+            }
+        };
+
+        // Handle running from a directory other than the top level
+        let top_level = output(self.git().args(&["rev-parse", "--show-toplevel"]));
+        let top_level = top_level.trim_end();
+        let compiler = format!("{top_level}/compiler/");
+        let library = format!("{top_level}/library/");
+
+        // Look for a version to compare to based on the current commit.
+        // Only commits merged by bors will have CI artifacts.
+        let merge_base = output(
+            self.git()
+                .arg("rev-list")
+                .arg(format!("--author={}", self.stage0_metadata.config.git_merge_commit_email))
+                .args(&["-n1", "--first-parent", "HEAD"]),
+        );
+        let commit = merge_base.trim_end();
+        if commit.is_empty() {
+            println!("error: could not find commit hash for downloading rustc");
+            println!("help: maybe your repository history is too shallow?");
+            println!("help: consider disabling `download-rustc`");
+            println!("help: or fetch enough history to include one upstream commit");
+            crate::detail_exit(1);
+        }
+
+        // Warn if there were changes to the compiler or standard library since the ancestor commit.
+        let has_changes = !t!(self
+            .git()
+            .args(&["diff-index", "--quiet", &commit, "--", &compiler, &library])
+            .status())
+        .success();
+        if has_changes {
+            if if_unchanged {
+                if self.verbose > 0 {
+                    println!(
+                        "warning: saw changes to compiler/ or library/ since {commit}; \
+                            ignoring `download-rustc`"
+                    );
+                }
+                return None;
+            }
+            println!(
+                "warning: `download-rustc` is enabled, but there are changes to \
+                    compiler/ or library/"
+            );
+        }
+
+        Some(commit.to_string())
+    }
 }
 
 fn set<T>(field: &mut T, val: Option<T>) {
@@ -1552,204 +1655,3 @@ fn threads_from_config(v: u32) -> u32 {
         n => n,
     }
 }
-
-/// Returns the commit to download, or `None` if we shouldn't download CI artifacts.
-fn download_ci_rustc_commit(
-    config: &Config,
-    download_rustc: Option<StringOrBool>,
-) -> Option<String> {
-    // If `download-rustc` is not set, default to rebuilding.
-    let if_unchanged = match download_rustc {
-        None | Some(StringOrBool::Bool(false)) => return None,
-        Some(StringOrBool::Bool(true)) => false,
-        Some(StringOrBool::String(s)) if s == "if-unchanged" => true,
-        Some(StringOrBool::String(other)) => {
-            panic!("unrecognized option for download-rustc: {}", other)
-        }
-    };
-
-    // Handle running from a directory other than the top level
-    let top_level = output(config.git().args(&["rev-parse", "--show-toplevel"]));
-    let top_level = top_level.trim_end();
-    let compiler = format!("{top_level}/compiler/");
-    let library = format!("{top_level}/library/");
-
-    // Look for a version to compare to based on the current commit.
-    // Only commits merged by bors will have CI artifacts.
-    let merge_base = output(
-        config
-            .git()
-            .arg("rev-list")
-            .arg(format!("--author={}", config.stage0_metadata.config.git_merge_commit_email))
-            .args(&["-n1", "--first-parent", "HEAD"]),
-    );
-    let commit = merge_base.trim_end();
-    if commit.is_empty() {
-        println!("error: could not find commit hash for downloading rustc");
-        println!("help: maybe your repository history is too shallow?");
-        println!("help: consider disabling `download-rustc`");
-        println!("help: or fetch enough history to include one upstream commit");
-        crate::detail_exit(1);
-    }
-
-    // Warn if there were changes to the compiler or standard library since the ancestor commit.
-    let has_changes = !t!(config
-        .git()
-        .args(&["diff-index", "--quiet", &commit, "--", &compiler, &library])
-        .status())
-    .success();
-    if has_changes {
-        if if_unchanged {
-            if config.verbose > 0 {
-                println!(
-                    "warning: saw changes to compiler/ or library/ since {commit}; \
-                          ignoring `download-rustc`"
-                );
-            }
-            return None;
-        }
-        println!(
-            "warning: `download-rustc` is enabled, but there are changes to \
-                  compiler/ or library/"
-        );
-    }
-
-    Some(commit.to_string())
-}
-
-fn maybe_download_rustfmt(builder: &Builder<'_>) -> Option<PathBuf> {
-    let RustfmtMetadata { date, version } = builder.config.stage0_metadata.rustfmt.as_ref()?;
-    let channel = format!("{version}-{date}");
-
-    let host = builder.config.build;
-    let rustfmt_path = builder.config.initial_rustc.with_file_name(exe("rustfmt", host));
-    let bin_root = builder.config.out.join(host.triple).join("stage0");
-    let rustfmt_stamp = bin_root.join(".rustfmt-stamp");
-    if rustfmt_path.exists() && !program_out_of_date(&rustfmt_stamp, &channel) {
-        return Some(rustfmt_path);
-    }
-
-    let filename = format!("rustfmt-{version}-{build}.tar.xz", build = host.triple);
-    download_component(builder, DownloadSource::Dist, filename, "rustfmt-preview", &date, "stage0");
-
-    builder.fix_bin_or_dylib(&bin_root.join("bin").join("rustfmt"));
-    builder.fix_bin_or_dylib(&bin_root.join("bin").join("cargo-fmt"));
-
-    builder.create(&rustfmt_stamp, &channel);
-    Some(rustfmt_path)
-}
-
-fn download_ci_rustc(builder: &Builder<'_>, commit: &str) {
-    builder.verbose(&format!("using downloaded stage2 artifacts from CI (commit {commit})"));
-    let channel = builder.config.artifact_channel(builder, commit);
-    let host = builder.config.build.triple;
-    let bin_root = builder.out.join(host).join("ci-rustc");
-    let rustc_stamp = bin_root.join(".rustc-stamp");
-
-    if !bin_root.join("bin").join("rustc").exists() || program_out_of_date(&rustc_stamp, commit) {
-        if bin_root.exists() {
-            t!(fs::remove_dir_all(&bin_root));
-        }
-        let filename = format!("rust-std-{channel}-{host}.tar.xz");
-        let pattern = format!("rust-std-{host}");
-        download_ci_component(builder, filename, &pattern, commit);
-        let filename = format!("rustc-{channel}-{host}.tar.xz");
-        download_ci_component(builder, filename, "rustc", commit);
-        // download-rustc doesn't need its own cargo, it can just use beta's.
-        let filename = format!("rustc-dev-{channel}-{host}.tar.xz");
-        download_ci_component(builder, filename, "rustc-dev", commit);
-
-        builder.fix_bin_or_dylib(&bin_root.join("bin").join("rustc"));
-        builder.fix_bin_or_dylib(&bin_root.join("bin").join("rustdoc"));
-        let lib_dir = bin_root.join("lib");
-        for lib in t!(fs::read_dir(&lib_dir), lib_dir.display().to_string()) {
-            let lib = t!(lib);
-            if lib.path().extension() == Some(OsStr::new("so")) {
-                builder.fix_bin_or_dylib(&lib.path());
-            }
-        }
-        t!(fs::write(rustc_stamp, commit));
-    }
-}
-
-pub(crate) enum DownloadSource {
-    CI,
-    Dist,
-}
-
-/// Download a single component of a CI-built toolchain (not necessarily a published nightly).
-// NOTE: intentionally takes an owned string to avoid downloading multiple times by accident
-fn download_ci_component(builder: &Builder<'_>, filename: String, prefix: &str, commit: &str) {
-    download_component(builder, DownloadSource::CI, filename, prefix, commit, "ci-rustc")
-}
-
-fn download_component(
-    builder: &Builder<'_>,
-    mode: DownloadSource,
-    filename: String,
-    prefix: &str,
-    key: &str,
-    destination: &str,
-) {
-    let cache_dst = builder.out.join("cache");
-    let cache_dir = cache_dst.join(key);
-    if !cache_dir.exists() {
-        t!(fs::create_dir_all(&cache_dir));
-    }
-
-    let bin_root = builder.out.join(builder.config.build.triple).join(destination);
-    let tarball = cache_dir.join(&filename);
-    let (base_url, url, should_verify) = match mode {
-        DownloadSource::CI => (
-            builder.config.stage0_metadata.config.artifacts_server.clone(),
-            format!("{key}/{filename}"),
-            false,
-        ),
-        DownloadSource::Dist => {
-            let dist_server = env::var("RUSTUP_DIST_SERVER")
-                .unwrap_or(builder.config.stage0_metadata.config.dist_server.to_string());
-            // NOTE: make `dist` part of the URL because that's how it's stored in src/stage0.json
-            (dist_server, format!("dist/{key}/{filename}"), true)
-        }
-    };
-
-    // For the beta compiler, put special effort into ensuring the checksums are valid.
-    // FIXME: maybe we should do this for download-rustc as well? but it would be a pain to update
-    // this on each and every nightly ...
-    let checksum = if should_verify {
-        let error = format!(
-            "src/stage0.json doesn't contain a checksum for {url}. \
-            Pre-built artifacts might not be available for this \
-            target at this time, see https://doc.rust-lang.org/nightly\
-            /rustc/platform-support.html for more information."
-        );
-        let sha256 = builder.config.stage0_metadata.checksums_sha256.get(&url).expect(&error);
-        if tarball.exists() {
-            if builder.verify(&tarball, sha256) {
-                builder.unpack(&tarball, &bin_root, prefix);
-                return;
-            } else {
-                builder.verbose(&format!(
-                    "ignoring cached file {} due to failed verification",
-                    tarball.display()
-                ));
-                builder.remove(&tarball);
-            }
-        }
-        Some(sha256)
-    } else if tarball.exists() {
-        builder.unpack(&tarball, &bin_root, prefix);
-        return;
-    } else {
-        None
-    };
-
-    builder.download_component(&format!("{base_url}/{url}"), &tarball, "");
-    if let Some(sha256) = checksum {
-        if !builder.verify(&tarball, sha256) {
-            panic!("failed to verify {}", tarball.display());
-        }
-    }
-
-    builder.unpack(&tarball, &bin_root, prefix);
-}
diff --git a/src/bootstrap/dist.rs b/src/bootstrap/dist.rs
index c636d4c2b47f..aacd2c7eab98 100644
--- a/src/bootstrap/dist.rs
+++ b/src/bootstrap/dist.rs
@@ -19,6 +19,7 @@ use crate::cache::{Interned, INTERNER};
 use crate::channel;
 use crate::compile;
 use crate::config::TargetSelection;
+use crate::doc::DocumentationFormat;
 use crate::tarball::{GeneratedTarball, OverlayKind, Tarball};
 use crate::tool::{self, Tool};
 use crate::util::{exe, is_dylib, output, t, timeit};
@@ -97,7 +98,11 @@ impl Step for JsonDocs {
     /// Builds the `rust-docs-json` installer component.
     fn run(self, builder: &Builder<'_>) -> Option<GeneratedTarball> {
         let host = self.host;
-        builder.ensure(crate::doc::JsonStd { stage: builder.top_stage, target: host });
+        builder.ensure(crate::doc::Std {
+            stage: builder.top_stage,
+            target: host,
+            format: DocumentationFormat::JSON,
+        });
 
         let dest = "share/doc/rust/json";
 
@@ -919,13 +924,13 @@ impl Step for PlainSourceTarball {
 
         // Create the version file
         builder.create(&plain_dst_src.join("version"), &builder.rust_version());
-        if let Some(info) = builder.rust_info.info() {
+        if let Some(info) = builder.rust_info().info() {
             channel::write_commit_hash_file(&plain_dst_src, &info.sha);
             channel::write_commit_info_file(&plain_dst_src, info);
         }
 
         // If we're building from git sources, we need to vendor a complete distribution.
-        if builder.rust_info.is_managed_git_subrepository() {
+        if builder.rust_info().is_managed_git_subrepository() {
             // Ensure we have the submodules checked out.
             builder.update_submodule(Path::new("src/tools/rust-analyzer"));
 
@@ -940,7 +945,7 @@ impl Step for PlainSourceTarball {
                 .arg(builder.src.join("./src/bootstrap/Cargo.toml"))
                 .current_dir(&plain_dst_src);
 
-            let config = if !builder.config.dry_run {
+            let config = if !builder.config.dry_run() {
                 t!(String::from_utf8(t!(cmd.output()).stdout))
             } else {
                 String::new()
@@ -1381,7 +1386,7 @@ impl Step for Extended {
         let etc = builder.src.join("src/etc/installer");
 
         // Avoid producing tarballs during a dry run.
-        if builder.config.dry_run {
+        if builder.config.dry_run() {
             return;
         }
 
@@ -1813,7 +1818,7 @@ impl Step for Extended {
             let _time = timeit(builder);
             builder.run(&mut cmd);
 
-            if !builder.config.dry_run {
+            if !builder.config.dry_run() {
                 t!(fs::rename(exe.join(&filename), distdir(builder).join(&filename)));
             }
         }
@@ -1847,21 +1852,23 @@ fn add_env(builder: &Builder<'_>, cmd: &mut Command, target: TargetSelection) {
 ///
 /// Returns whether the files were actually copied.
 fn maybe_install_llvm(builder: &Builder<'_>, target: TargetSelection, dst_libdir: &Path) -> bool {
-    if !builder.is_rust_llvm(target) {
-        // If the LLVM was externally provided, then we don't currently copy
-        // artifacts into the sysroot. This is not necessarily the right
-        // choice (in particular, it will require the LLVM dylib to be in
-        // the linker's load path at runtime), but the common use case for
-        // external LLVMs is distribution provided LLVMs, and in that case
-        // they're usually in the standard search path (e.g., /usr/lib) and
-        // copying them here is going to cause problems as we may end up
-        // with the wrong files and isn't what distributions want.
-        //
-        // This behavior may be revisited in the future though.
-        //
-        // If the LLVM is coming from ourselves (just from CI) though, we
-        // still want to install it, as it otherwise won't be available.
-        return false;
+    if let Some(config) = builder.config.target_config.get(&target) {
+        if config.llvm_config.is_some() && !builder.config.llvm_from_ci {
+            // If the LLVM was externally provided, then we don't currently copy
+            // artifacts into the sysroot. This is not necessarily the right
+            // choice (in particular, it will require the LLVM dylib to be in
+            // the linker's load path at runtime), but the common use case for
+            // external LLVMs is distribution provided LLVMs, and in that case
+            // they're usually in the standard search path (e.g., /usr/lib) and
+            // copying them here is going to cause problems as we may end up
+            // with the wrong files and isn't what distributions want.
+            //
+            // This behavior may be revisited in the future though.
+            //
+            // If the LLVM is coming from ourselves (just from CI) though, we
+            // still want to install it, as it otherwise won't be available.
+            return false;
+        }
     }
 
     // On macOS, rustc (and LLVM tools) link to an unversioned libLLVM.dylib
@@ -1875,12 +1882,12 @@ fn maybe_install_llvm(builder: &Builder<'_>, target: TargetSelection, dst_libdir
         if llvm_dylib_path.exists() {
             builder.install(&llvm_dylib_path, dst_libdir, 0o644);
         }
-        !builder.config.dry_run
+        !builder.config.dry_run()
     } else if let Ok(llvm_config) = crate::native::prebuilt_llvm_config(builder, target) {
         let mut cmd = Command::new(llvm_config);
         cmd.arg("--libfiles");
         builder.verbose(&format!("running {:?}", cmd));
-        let files = if builder.config.dry_run { "".into() } else { output(&mut cmd) };
+        let files = if builder.config.dry_run() { "".into() } else { output(&mut cmd) };
         let build_llvm_out = &builder.llvm_out(builder.config.build);
         let target_llvm_out = &builder.llvm_out(target);
         for file in files.trim_end().split(' ') {
@@ -1892,7 +1899,7 @@ fn maybe_install_llvm(builder: &Builder<'_>, target: TargetSelection, dst_libdir
             };
             builder.install(&file, dst_libdir, 0o644);
         }
-        !builder.config.dry_run
+        !builder.config.dry_run()
     } else {
         false
     }
diff --git a/src/bootstrap/doc.rs b/src/bootstrap/doc.rs
index 7bdd226cb692..3180a12c85be 100644
--- a/src/bootstrap/doc.rs
+++ b/src/bootstrap/doc.rs
@@ -85,18 +85,6 @@ book!(
     StyleGuide, "src/doc/style-guide", "style-guide";
 );
 
-fn open(builder: &Builder<'_>, path: impl AsRef<Path>) {
-    if builder.config.dry_run || !builder.config.cmd.open() {
-        return;
-    }
-
-    let path = path.as_ref();
-    builder.info(&format!("Opening doc {}", path.display()));
-    if let Err(err) = opener::open(path) {
-        builder.info(&format!("{}\n", err));
-    }
-}
-
 // "library/std" -> ["library", "std"]
 //
 // Used for deciding whether a particular step is one requested by the user on
@@ -163,7 +151,7 @@ impl Step for RustbookSrc {
         let index = out.join("index.html");
         let rustbook = builder.tool_exe(Tool::Rustbook);
         let mut rustbook_cmd = builder.tool_cmd(Tool::Rustbook);
-        if builder.config.dry_run || up_to_date(&src, &index) && up_to_date(&rustbook, &index) {
+        if builder.config.dry_run() || up_to_date(&src, &index) && up_to_date(&rustbook, &index) {
             return;
         }
         builder.info(&format!("Rustbook ({}) - {}", target, name));
@@ -228,7 +216,7 @@ impl Step for TheBook {
         }
 
         // build the version info page and CSS
-        builder.ensure(Standalone { compiler, target });
+        let shared_assets = builder.ensure(SharedAssets { target });
 
         // build the redirect pages
         builder.info(&format!("Documenting book redirect pages ({})", target));
@@ -237,20 +225,19 @@ impl Step for TheBook {
             let path = file.path();
             let path = path.to_str().unwrap();
 
-            invoke_rustdoc(builder, compiler, target, path);
+            invoke_rustdoc(builder, compiler, &shared_assets, target, path);
         }
 
-        if builder.was_invoked_explicitly::<Self>(Kind::Doc) {
-            let out = builder.doc_out(target);
-            let index = out.join("book").join("index.html");
-            open(builder, &index);
-        }
+        let out = builder.doc_out(target);
+        let index = out.join("book").join("index.html");
+        builder.maybe_open_in_browser::<Self>(index);
     }
 }
 
 fn invoke_rustdoc(
     builder: &Builder<'_>,
     compiler: Compiler,
+    shared_assets: &SharedAssetsPaths,
     target: TargetSelection,
     markdown: &str,
 ) {
@@ -260,7 +247,6 @@ fn invoke_rustdoc(
 
     let header = builder.src.join("src/doc/redirect.inc");
     let footer = builder.src.join("src/doc/footer.inc");
-    let version_info = out.join("version_info.html");
 
     let mut cmd = builder.rustdoc_cmd(compiler);
 
@@ -269,7 +255,7 @@ fn invoke_rustdoc(
     cmd.arg("--html-after-content")
         .arg(&footer)
         .arg("--html-before-content")
-        .arg(&version_info)
+        .arg(&shared_assets.version_info)
         .arg("--html-in-header")
         .arg(&header)
         .arg("--markdown-no-toc")
@@ -300,7 +286,7 @@ impl Step for Standalone {
 
     fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
         let builder = run.builder;
-        run.path("src/doc").default_condition(builder.config.docs)
+        run.path("src/doc").alias("standalone").default_condition(builder.config.docs)
     }
 
     fn make_run(run: RunConfig<'_>) {
@@ -325,21 +311,11 @@ impl Step for Standalone {
         let out = builder.doc_out(target);
         t!(fs::create_dir_all(&out));
 
+        let version_info = builder.ensure(SharedAssets { target: self.target }).version_info;
+
         let favicon = builder.src.join("src/doc/favicon.inc");
         let footer = builder.src.join("src/doc/footer.inc");
         let full_toc = builder.src.join("src/doc/full-toc.inc");
-        t!(fs::copy(builder.src.join("src/doc/rust.css"), out.join("rust.css")));
-
-        let version_input = builder.src.join("src/doc/version_info.html.template");
-        let version_info = out.join("version_info.html");
-
-        if !builder.config.dry_run && !up_to_date(&version_input, &version_info) {
-            let info = t!(fs::read_to_string(&version_input))
-                .replace("VERSION", &builder.rust_release())
-                .replace("SHORT_HASH", builder.rust_info.sha_short().unwrap_or(""))
-                .replace("STAMP", builder.rust_info.sha().unwrap_or(""));
-            t!(fs::write(&version_info, &info));
-        }
 
         for file in t!(fs::read_dir(builder.src.join("src/doc"))) {
             let file = t!(file);
@@ -355,8 +331,8 @@ impl Step for Standalone {
                 && up_to_date(&footer, &html)
                 && up_to_date(&favicon, &html)
                 && up_to_date(&full_toc, &html)
-                && (builder.config.dry_run || up_to_date(&version_info, &html))
-                && (builder.config.dry_run || up_to_date(&rustdoc, &html))
+                && (builder.config.dry_run() || up_to_date(&version_info, &html))
+                && (builder.config.dry_run() || up_to_date(&rustdoc, &html))
             {
                 continue;
             }
@@ -396,15 +372,55 @@ impl Step for Standalone {
         // with no particular explicit doc requested (e.g. library/core).
         if builder.paths.is_empty() || builder.was_invoked_explicitly::<Self>(Kind::Doc) {
             let index = out.join("index.html");
-            open(builder, &index);
+            builder.open_in_browser(&index);
         }
     }
 }
 
+#[derive(Debug, Clone)]
+pub struct SharedAssetsPaths {
+    pub version_info: PathBuf,
+}
+
+#[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
+pub struct SharedAssets {
+    target: TargetSelection,
+}
+
+impl Step for SharedAssets {
+    type Output = SharedAssetsPaths;
+    const DEFAULT: bool = false;
+
+    fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
+        // Other tasks depend on this, no need to execute it on its own
+        run.never()
+    }
+
+    // Generate shared resources used by other pieces of documentation.
+    fn run(self, builder: &Builder<'_>) -> Self::Output {
+        let out = builder.doc_out(self.target);
+
+        let version_input = builder.src.join("src").join("doc").join("version_info.html.template");
+        let version_info = out.join("version_info.html");
+        if !builder.config.dry_run() && !up_to_date(&version_input, &version_info) {
+            let info = t!(fs::read_to_string(&version_input))
+                .replace("VERSION", &builder.rust_release())
+                .replace("SHORT_HASH", builder.rust_info().sha_short().unwrap_or(""))
+                .replace("STAMP", builder.rust_info().sha().unwrap_or(""));
+            t!(fs::write(&version_info, &info));
+        }
+
+        builder.copy(&builder.src.join("src").join("doc").join("rust.css"), &out.join("rust.css"));
+
+        SharedAssetsPaths { version_info }
+    }
+}
+
 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
 pub struct Std {
     pub stage: u32,
     pub target: TargetSelection,
+    pub format: DocumentationFormat,
 }
 
 impl Step for Std {
@@ -417,7 +433,15 @@ impl Step for Std {
     }
 
     fn make_run(run: RunConfig<'_>) {
-        run.builder.ensure(Std { stage: run.builder.top_stage, target: run.target });
+        run.builder.ensure(Std {
+            stage: run.builder.top_stage,
+            target: run.target,
+            format: if run.builder.config.cmd.json() {
+                DocumentationFormat::JSON
+            } else {
+                DocumentationFormat::HTML
+            },
+        });
     }
 
     /// Compile all standard library documentation.
@@ -427,18 +451,26 @@ impl Step for Std {
     fn run(self, builder: &Builder<'_>) {
         let stage = self.stage;
         let target = self.target;
-        let out = builder.doc_out(target);
+        let out = match self.format {
+            DocumentationFormat::HTML => builder.doc_out(target),
+            DocumentationFormat::JSON => builder.json_doc_out(target),
+        };
+
         t!(fs::create_dir_all(&out));
-        t!(fs::copy(builder.src.join("src/doc/rust.css"), out.join("rust.css")));
+
+        builder.ensure(SharedAssets { target: self.target });
 
         let index_page = builder.src.join("src/doc/index.md").into_os_string();
-        let mut extra_args = vec![
-            OsStr::new("--markdown-css"),
-            OsStr::new("rust.css"),
-            OsStr::new("--markdown-no-toc"),
-            OsStr::new("--index-page"),
-            &index_page,
-        ];
+        let mut extra_args = match self.format {
+            DocumentationFormat::HTML => vec![
+                OsStr::new("--markdown-css"),
+                OsStr::new("rust.css"),
+                OsStr::new("--markdown-no-toc"),
+                OsStr::new("--index-page"),
+                &index_page,
+            ],
+            DocumentationFormat::JSON => vec![OsStr::new("--output-format"), OsStr::new("json")],
+        };
 
         if !builder.config.docs_minification {
             extra_args.push(OsStr::new("--disable-minification"));
@@ -462,59 +494,24 @@ impl Step for Std {
             })
             .collect::<Vec<_>>();
 
-        doc_std(
-            builder,
-            DocumentationFormat::HTML,
-            stage,
-            target,
-            &out,
-            &extra_args,
-            &requested_crates,
-        );
+        doc_std(builder, self.format, stage, target, &out, &extra_args, &requested_crates);
+
+        // Don't open if the format is json
+        if let DocumentationFormat::JSON = self.format {
+            return;
+        }
 
         // Look for library/std, library/core etc in the `x.py doc` arguments and
         // open the corresponding rendered docs.
         for requested_crate in requested_crates {
             if STD_PUBLIC_CRATES.iter().any(|k| *k == requested_crate.as_str()) {
                 let index = out.join(requested_crate).join("index.html");
-                open(builder, &index);
+                builder.open_in_browser(index);
             }
         }
     }
 }
 
-#[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
-pub struct JsonStd {
-    pub stage: u32,
-    pub target: TargetSelection,
-}
-
-impl Step for JsonStd {
-    type Output = ();
-    const DEFAULT: bool = false;
-
-    fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
-        let default = run.builder.config.docs && run.builder.config.cmd.json();
-        run.all_krates("test").path("library").default_condition(default)
-    }
-
-    fn make_run(run: RunConfig<'_>) {
-        run.builder.ensure(Std { stage: run.builder.top_stage, target: run.target });
-    }
-
-    /// Build JSON documentation for the standard library crates.
-    ///
-    /// This is largely just a wrapper around `cargo doc`.
-    fn run(self, builder: &Builder<'_>) {
-        let stage = self.stage;
-        let target = self.target;
-        let out = builder.json_doc_out(target);
-        t!(fs::create_dir_all(&out));
-        let extra_args = [OsStr::new("--output-format"), OsStr::new("json")];
-        doc_std(builder, DocumentationFormat::JSON, stage, target, &out, &extra_args, &[])
-    }
-}
-
 /// Name of the crates that are visible to consumers of the standard library.
 /// Documentation for internal crates is handled by the rustc step, so internal crates will show
 /// up there.
@@ -527,7 +524,7 @@ impl Step for JsonStd {
 const STD_PUBLIC_CRATES: [&str; 5] = ["core", "alloc", "std", "proc_macro", "test"];
 
 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
-enum DocumentationFormat {
+pub enum DocumentationFormat {
     HTML,
     JSON,
 }
@@ -729,13 +726,13 @@ impl Step for Rustc {
         // Let's open the first crate documentation page:
         if let Some(krate) = to_open {
             let index = out.join(krate).join("index.html");
-            open(builder, &index);
+            builder.open_in_browser(index);
         }
     }
 }
 
 macro_rules! tool_doc {
-    ($tool: ident, $should_run: literal, $path: literal, [$($krate: literal),+ $(,)?], in_tree = $in_tree:expr $(,)?) => {
+    ($tool: ident, $should_run: literal, $path: literal, [$($krate: literal),+ $(,)?] $(,)?) => {
         #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
         pub struct $tool {
             target: TargetSelection,
@@ -791,12 +788,6 @@ macro_rules! tool_doc {
                 t!(fs::create_dir_all(&out_dir));
                 t!(symlink_dir_force(&builder.config, &out, &out_dir));
 
-                let source_type = if $in_tree == true {
-                    SourceType::InTree
-                } else {
-                    SourceType::Submodule
-                };
-
                 // Build cargo command.
                 let mut cargo = prepare_tool_cargo(
                     builder,
@@ -805,7 +796,7 @@ macro_rules! tool_doc {
                     target,
                     "doc",
                     $path,
-                    source_type,
+                    SourceType::InTree,
                     &[],
                 );
 
@@ -821,38 +812,21 @@ macro_rules! tool_doc {
                 cargo.rustdocflag("--show-type-layout");
                 cargo.rustdocflag("--generate-link-to-definition");
                 cargo.rustdocflag("-Zunstable-options");
-                if $in_tree == true {
-                    builder.run(&mut cargo.into());
-                } else {
-                    // Allow out-of-tree docs to fail (since the tool might be in a broken state).
-                    if !builder.try_run(&mut cargo.into()) {
-                        builder.info(&format!(
-                            "WARNING: tool {} failed to document; ignoring failure because it is an out-of-tree tool",
-                            stringify!($tool).to_lowercase(),
-                        ));
-                    }
-                }
+                builder.run(&mut cargo.into());
             }
         }
     }
 }
 
-tool_doc!(
-    Rustdoc,
-    "rustdoc-tool",
-    "src/tools/rustdoc",
-    ["rustdoc", "rustdoc-json-types"],
-    in_tree = true
-);
+tool_doc!(Rustdoc, "rustdoc-tool", "src/tools/rustdoc", ["rustdoc", "rustdoc-json-types"],);
 tool_doc!(
     Rustfmt,
     "rustfmt-nightly",
     "src/tools/rustfmt",
     ["rustfmt-nightly", "rustfmt-config_proc_macro"],
-    in_tree = true
 );
-tool_doc!(Clippy, "clippy", "src/tools/clippy", ["clippy_utils"], in_tree = true);
-tool_doc!(Miri, "miri", "src/tools/miri", ["miri"], in_tree = false);
+tool_doc!(Clippy, "clippy", "src/tools/clippy", ["clippy_utils"]);
+tool_doc!(Miri, "miri", "src/tools/miri", ["miri"]);
 
 #[derive(Ord, PartialOrd, Debug, Copy, Clone, Hash, PartialEq, Eq)]
 pub struct ErrorIndex {
@@ -926,7 +900,7 @@ impl Step for UnstableBookGen {
 }
 
 fn symlink_dir_force(config: &Config, src: &Path, dst: &Path) -> io::Result<()> {
-    if config.dry_run {
+    if config.dry_run() {
         return Ok(());
     }
     if let Ok(m) = fs::symlink_metadata(dst) {
@@ -991,7 +965,7 @@ impl Step for RustcBook {
         cmd.arg("--rustc");
         cmd.arg(&rustc);
         cmd.arg("--rustc-target").arg(&self.target.rustc_target_arg());
-        if builder.config.verbose() {
+        if builder.is_verbose() {
             cmd.arg("--verbose");
         }
         if self.validate {
@@ -1012,10 +986,9 @@ impl Step for RustcBook {
             name: INTERNER.intern_str("rustc"),
             src: INTERNER.intern_path(out_base),
         });
-        if builder.was_invoked_explicitly::<Self>(Kind::Doc) {
-            let out = builder.doc_out(self.target);
-            let index = out.join("rustc").join("index.html");
-            open(builder, &index);
-        }
+
+        let out = builder.doc_out(self.target);
+        let index = out.join("rustc").join("index.html");
+        builder.maybe_open_in_browser::<Self>(index);
     }
 }
diff --git a/src/bootstrap/download.rs b/src/bootstrap/download.rs
new file mode 100644
index 000000000000..d0f389df9734
--- /dev/null
+++ b/src/bootstrap/download.rs
@@ -0,0 +1,519 @@
+use std::{
+    env,
+    ffi::{OsStr, OsString},
+    fs::{self, File},
+    io::{BufRead, BufReader, ErrorKind},
+    path::{Path, PathBuf},
+    process::{Command, Stdio},
+};
+
+use once_cell::sync::OnceCell;
+use xz2::bufread::XzDecoder;
+
+use crate::{
+    config::RustfmtMetadata,
+    native::detect_llvm_sha,
+    t,
+    util::{check_run, exe, program_out_of_date, try_run},
+    Config,
+};
+
+/// Generic helpers that are useful anywhere in bootstrap.
+impl Config {
+    pub fn is_verbose(&self) -> bool {
+        self.verbose > 0
+    }
+
+    pub(crate) fn create(&self, path: &Path, s: &str) {
+        if self.dry_run() {
+            return;
+        }
+        t!(fs::write(path, s));
+    }
+
+    pub(crate) fn remove(&self, f: &Path) {
+        if self.dry_run() {
+            return;
+        }
+        fs::remove_file(f).unwrap_or_else(|_| panic!("failed to remove {:?}", f));
+    }
+
+    /// Create a temporary directory in `out` and return its path.
+    ///
+    /// NOTE: this temporary directory is shared between all steps;
+    /// if you need an empty directory, create a new subdirectory inside it.
+    pub(crate) fn tempdir(&self) -> PathBuf {
+        let tmp = self.out.join("tmp");
+        t!(fs::create_dir_all(&tmp));
+        tmp
+    }
+
+    /// Runs a command, printing out nice contextual information if it fails.
+    /// Exits if the command failed to execute at all, otherwise returns its
+    /// `status.success()`.
+    pub(crate) fn try_run(&self, cmd: &mut Command) -> bool {
+        if self.dry_run() {
+            return true;
+        }
+        self.verbose(&format!("running: {:?}", cmd));
+        try_run(cmd, self.is_verbose())
+    }
+
+    /// Runs a command, printing out nice contextual information if it fails.
+    /// Returns false if do not execute at all, otherwise returns its
+    /// `status.success()`.
+    pub(crate) fn check_run(&self, cmd: &mut Command) -> bool {
+        if self.dry_run() {
+            return true;
+        }
+        self.verbose(&format!("running: {:?}", cmd));
+        check_run(cmd, self.is_verbose())
+    }
+
+    /// Modifies the interpreter section of 'fname' to fix the dynamic linker,
+    /// or the RPATH section, to fix the dynamic library search path
+    ///
+    /// This is only required on NixOS and uses the PatchELF utility to
+    /// change the interpreter/RPATH of ELF executables.
+    ///
+    /// Please see https://nixos.org/patchelf.html for more information
+    fn fix_bin_or_dylib(&self, fname: &Path) {
+        // FIXME: cache NixOS detection?
+        match Command::new("uname").arg("-s").stderr(Stdio::inherit()).output() {
+            Err(_) => return,
+            Ok(output) if !output.status.success() => return,
+            Ok(output) => {
+                let mut s = output.stdout;
+                if s.last() == Some(&b'\n') {
+                    s.pop();
+                }
+                if s != b"Linux" {
+                    return;
+                }
+            }
+        }
+
+        // If the user has asked binaries to be patched for Nix, then
+        // don't check for NixOS or `/lib`, just continue to the patching.
+        // NOTE: this intentionally comes after the Linux check:
+        // - patchelf only works with ELF files, so no need to run it on Mac or Windows
+        // - On other Unix systems, there is no stable syscall interface, so Nix doesn't manage the global libc.
+        if !self.patch_binaries_for_nix {
+            // Use `/etc/os-release` instead of `/etc/NIXOS`.
+            // The latter one does not exist on NixOS when using tmpfs as root.
+            const NIX_IDS: &[&str] = &["ID=nixos", "ID='nixos'", "ID=\"nixos\""];
+            let os_release = match File::open("/etc/os-release") {
+                Err(e) if e.kind() == ErrorKind::NotFound => return,
+                Err(e) => panic!("failed to access /etc/os-release: {}", e),
+                Ok(f) => f,
+            };
+            if !BufReader::new(os_release).lines().any(|l| NIX_IDS.contains(&t!(l).trim())) {
+                return;
+            }
+            if Path::new("/lib").exists() {
+                return;
+            }
+        }
+
+        // At this point we're pretty sure the user is running NixOS or using Nix
+        println!("info: you seem to be using Nix. Attempting to patch {}", fname.display());
+
+        // Only build `.nix-deps` once.
+        static NIX_DEPS_DIR: OnceCell<PathBuf> = OnceCell::new();
+        let mut nix_build_succeeded = true;
+        let nix_deps_dir = NIX_DEPS_DIR.get_or_init(|| {
+            // Run `nix-build` to "build" each dependency (which will likely reuse
+            // the existing `/nix/store` copy, or at most download a pre-built copy).
+            //
+            // Importantly, we create a gc-root called `.nix-deps` in the `build/`
+            // directory, but still reference the actual `/nix/store` path in the rpath
+            // as it makes it significantly more robust against changes to the location of
+            // the `.nix-deps` location.
+            //
+            // bintools: Needed for the path of `ld-linux.so` (via `nix-support/dynamic-linker`).
+            // zlib: Needed as a system dependency of `libLLVM-*.so`.
+            // patchelf: Needed for patching ELF binaries (see doc comment above).
+            let nix_deps_dir = self.out.join(".nix-deps");
+            const NIX_EXPR: &str = "
+            with (import <nixpkgs> {});
+            symlinkJoin {
+                name = \"rust-stage0-dependencies\";
+                paths = [
+                    zlib
+                    patchelf
+                    stdenv.cc.bintools
+                ];
+            }
+            ";
+            nix_build_succeeded = self.try_run(Command::new("nix-build").args(&[
+                Path::new("-E"),
+                Path::new(NIX_EXPR),
+                Path::new("-o"),
+                &nix_deps_dir,
+            ]));
+            nix_deps_dir
+        });
+        if !nix_build_succeeded {
+            return;
+        }
+
+        let mut patchelf = Command::new(nix_deps_dir.join("bin/patchelf"));
+        let rpath_entries = {
+            // ORIGIN is a relative default, all binary and dynamic libraries we ship
+            // appear to have this (even when `../lib` is redundant).
+            // NOTE: there are only two paths here, delimited by a `:`
+            let mut entries = OsString::from("$ORIGIN/../lib:");
+            entries.push(t!(fs::canonicalize(nix_deps_dir)));
+            entries.push("/lib");
+            entries
+        };
+        patchelf.args(&[OsString::from("--set-rpath"), rpath_entries]);
+        if !fname.extension().map_or(false, |ext| ext == "so") {
+            // Finally, set the correct .interp for binaries
+            let dynamic_linker_path = nix_deps_dir.join("nix-support/dynamic-linker");
+            // FIXME: can we support utf8 here? `args` doesn't accept Vec<u8>, only OsString ...
+            let dynamic_linker = t!(String::from_utf8(t!(fs::read(dynamic_linker_path))));
+            patchelf.args(&["--set-interpreter", dynamic_linker.trim_end()]);
+        }
+
+        self.try_run(patchelf.arg(fname));
+    }
+
+    fn download_file(&self, url: &str, dest_path: &Path, help_on_error: &str) {
+        self.verbose(&format!("download {url}"));
+        // Use a temporary file in case we crash while downloading, to avoid a corrupt download in cache/.
+        let tempfile = self.tempdir().join(dest_path.file_name().unwrap());
+        // While bootstrap itself only supports http and https downloads, downstream forks might
+        // need to download components from other protocols. The match allows them adding more
+        // protocols without worrying about merge conflicts if we change the HTTP implementation.
+        match url.split_once("://").map(|(proto, _)| proto) {
+            Some("http") | Some("https") => {
+                self.download_http_with_retries(&tempfile, url, help_on_error)
+            }
+            Some(other) => panic!("unsupported protocol {other} in {url}"),
+            None => panic!("no protocol in {url}"),
+        }
+        t!(std::fs::rename(&tempfile, dest_path));
+    }
+
+    fn download_http_with_retries(&self, tempfile: &Path, url: &str, help_on_error: &str) {
+        println!("downloading {}", url);
+        // Try curl. If that fails and we are on windows, fallback to PowerShell.
+        let mut curl = Command::new("curl");
+        curl.args(&[
+            "-#",
+            "-y",
+            "30",
+            "-Y",
+            "10", // timeout if speed is < 10 bytes/sec for > 30 seconds
+            "--connect-timeout",
+            "30", // timeout if cannot connect within 30 seconds
+            "--retry",
+            "3",
+            "-Sf",
+            "-o",
+        ]);
+        curl.arg(tempfile);
+        curl.arg(url);
+        if !self.check_run(&mut curl) {
+            if self.build.contains("windows-msvc") {
+                println!("Fallback to PowerShell");
+                for _ in 0..3 {
+                    if self.try_run(Command::new("PowerShell.exe").args(&[
+                        "/nologo",
+                        "-Command",
+                        "[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12;",
+                        &format!(
+                            "(New-Object System.Net.WebClient).DownloadFile('{}', '{}')",
+                            url, tempfile.to_str().expect("invalid UTF-8 not supported with powershell downloads"),
+                        ),
+                    ])) {
+                        return;
+                    }
+                    println!("\nspurious failure, trying again");
+                }
+            }
+            if !help_on_error.is_empty() {
+                eprintln!("{}", help_on_error);
+            }
+            crate::detail_exit(1);
+        }
+    }
+
+    fn unpack(&self, tarball: &Path, dst: &Path, pattern: &str) {
+        println!("extracting {} to {}", tarball.display(), dst.display());
+        if !dst.exists() {
+            t!(fs::create_dir_all(dst));
+        }
+
+        // `tarball` ends with `.tar.xz`; strip that suffix
+        // example: `rust-dev-nightly-x86_64-unknown-linux-gnu`
+        let uncompressed_filename =
+            Path::new(tarball.file_name().expect("missing tarball filename")).file_stem().unwrap();
+        let directory_prefix = Path::new(Path::new(uncompressed_filename).file_stem().unwrap());
+
+        // decompress the file
+        let data = t!(File::open(tarball));
+        let decompressor = XzDecoder::new(BufReader::new(data));
+
+        let mut tar = tar::Archive::new(decompressor);
+        for member in t!(tar.entries()) {
+            let mut member = t!(member);
+            let original_path = t!(member.path()).into_owned();
+            // skip the top-level directory
+            if original_path == directory_prefix {
+                continue;
+            }
+            let mut short_path = t!(original_path.strip_prefix(directory_prefix));
+            if !short_path.starts_with(pattern) {
+                continue;
+            }
+            short_path = t!(short_path.strip_prefix(pattern));
+            let dst_path = dst.join(short_path);
+            self.verbose(&format!("extracting {} to {}", original_path.display(), dst.display()));
+            if !t!(member.unpack_in(dst)) {
+                panic!("path traversal attack ??");
+            }
+            let src_path = dst.join(original_path);
+            if src_path.is_dir() && dst_path.exists() {
+                continue;
+            }
+            t!(fs::rename(src_path, dst_path));
+        }
+        t!(fs::remove_dir_all(dst.join(directory_prefix)));
+    }
+
+    /// Returns whether the SHA256 checksum of `path` matches `expected`.
+    fn verify(&self, path: &Path, expected: &str) -> bool {
+        use sha2::Digest;
+
+        self.verbose(&format!("verifying {}", path.display()));
+        let mut hasher = sha2::Sha256::new();
+        // FIXME: this is ok for rustfmt (4.1 MB large at time of writing), but it seems memory-intensive for rustc and larger components.
+        // Consider using streaming IO instead?
+        let contents = if self.dry_run() { vec![] } else { t!(fs::read(path)) };
+        hasher.update(&contents);
+        let found = hex::encode(hasher.finalize().as_slice());
+        let verified = found == expected;
+        if !verified && !self.dry_run() {
+            println!(
+                "invalid checksum: \n\
+                found:    {found}\n\
+                expected: {expected}",
+            );
+        }
+        return verified;
+    }
+}
+
+enum DownloadSource {
+    CI,
+    Dist,
+}
+
+/// Functions that are only ever called once, but named for clarify and to avoid thousand-line functions.
+impl Config {
+    pub(crate) fn maybe_download_rustfmt(&self) -> Option<PathBuf> {
+        let RustfmtMetadata { date, version } = self.stage0_metadata.rustfmt.as_ref()?;
+        let channel = format!("{version}-{date}");
+
+        let host = self.build;
+        let rustfmt_path = self.initial_rustc.with_file_name(exe("rustfmt", host));
+        let bin_root = self.out.join(host.triple).join("stage0");
+        let rustfmt_stamp = bin_root.join(".rustfmt-stamp");
+        if rustfmt_path.exists() && !program_out_of_date(&rustfmt_stamp, &channel) {
+            return Some(rustfmt_path);
+        }
+
+        let filename = format!("rustfmt-{version}-{build}.tar.xz", build = host.triple);
+        self.download_component(DownloadSource::Dist, filename, "rustfmt-preview", &date, "stage0");
+
+        self.fix_bin_or_dylib(&bin_root.join("bin").join("rustfmt"));
+        self.fix_bin_or_dylib(&bin_root.join("bin").join("cargo-fmt"));
+
+        self.create(&rustfmt_stamp, &channel);
+        Some(rustfmt_path)
+    }
+
+    pub(crate) fn download_ci_rustc(&self, commit: &str) {
+        self.verbose(&format!("using downloaded stage2 artifacts from CI (commit {commit})"));
+        let version = self.artifact_version_part(commit);
+        let host = self.build.triple;
+        let bin_root = self.out.join(host).join("ci-rustc");
+        let rustc_stamp = bin_root.join(".rustc-stamp");
+
+        if !bin_root.join("bin").join("rustc").exists() || program_out_of_date(&rustc_stamp, commit)
+        {
+            if bin_root.exists() {
+                t!(fs::remove_dir_all(&bin_root));
+            }
+            let filename = format!("rust-std-{version}-{host}.tar.xz");
+            let pattern = format!("rust-std-{host}");
+            self.download_ci_component(filename, &pattern, commit);
+            let filename = format!("rustc-{version}-{host}.tar.xz");
+            self.download_ci_component(filename, "rustc", commit);
+            // download-rustc doesn't need its own cargo, it can just use beta's.
+            let filename = format!("rustc-dev-{version}-{host}.tar.xz");
+            self.download_ci_component(filename, "rustc-dev", commit);
+            let filename = format!("rust-src-{version}.tar.xz");
+            self.download_ci_component(filename, "rust-src", commit);
+
+            self.fix_bin_or_dylib(&bin_root.join("bin").join("rustc"));
+            self.fix_bin_or_dylib(&bin_root.join("bin").join("rustdoc"));
+            let lib_dir = bin_root.join("lib");
+            for lib in t!(fs::read_dir(&lib_dir), lib_dir.display().to_string()) {
+                let lib = t!(lib);
+                if lib.path().extension() == Some(OsStr::new("so")) {
+                    self.fix_bin_or_dylib(&lib.path());
+                }
+            }
+            t!(fs::write(rustc_stamp, commit));
+        }
+    }
+
+    /// Download a single component of a CI-built toolchain (not necessarily a published nightly).
+    // NOTE: intentionally takes an owned string to avoid downloading multiple times by accident
+    fn download_ci_component(&self, filename: String, prefix: &str, commit: &str) {
+        Self::download_component(self, DownloadSource::CI, filename, prefix, commit, "ci-rustc")
+    }
+
+    fn download_component(
+        &self,
+        mode: DownloadSource,
+        filename: String,
+        prefix: &str,
+        key: &str,
+        destination: &str,
+    ) {
+        let cache_dst = self.out.join("cache");
+        let cache_dir = cache_dst.join(key);
+        if !cache_dir.exists() {
+            t!(fs::create_dir_all(&cache_dir));
+        }
+
+        let bin_root = self.out.join(self.build.triple).join(destination);
+        let tarball = cache_dir.join(&filename);
+        let (base_url, url, should_verify) = match mode {
+            DownloadSource::CI => (
+                self.stage0_metadata.config.artifacts_server.clone(),
+                format!("{key}/{filename}"),
+                false,
+            ),
+            DownloadSource::Dist => {
+                let dist_server = env::var("RUSTUP_DIST_SERVER")
+                    .unwrap_or(self.stage0_metadata.config.dist_server.to_string());
+                // NOTE: make `dist` part of the URL because that's how it's stored in src/stage0.json
+                (dist_server, format!("dist/{key}/{filename}"), true)
+            }
+        };
+
+        // For the beta compiler, put special effort into ensuring the checksums are valid.
+        // FIXME: maybe we should do this for download-rustc as well? but it would be a pain to update
+        // this on each and every nightly ...
+        let checksum = if should_verify {
+            let error = format!(
+                "src/stage0.json doesn't contain a checksum for {url}. \
+                Pre-built artifacts might not be available for this \
+                target at this time, see https://doc.rust-lang.org/nightly\
+                /rustc/platform-support.html for more information."
+            );
+            let sha256 = self.stage0_metadata.checksums_sha256.get(&url).expect(&error);
+            if tarball.exists() {
+                if self.verify(&tarball, sha256) {
+                    self.unpack(&tarball, &bin_root, prefix);
+                    return;
+                } else {
+                    self.verbose(&format!(
+                        "ignoring cached file {} due to failed verification",
+                        tarball.display()
+                    ));
+                    self.remove(&tarball);
+                }
+            }
+            Some(sha256)
+        } else if tarball.exists() {
+            self.unpack(&tarball, &bin_root, prefix);
+            return;
+        } else {
+            None
+        };
+
+        self.download_file(&format!("{base_url}/{url}"), &tarball, "");
+        if let Some(sha256) = checksum {
+            if !self.verify(&tarball, sha256) {
+                panic!("failed to verify {}", tarball.display());
+            }
+        }
+
+        self.unpack(&tarball, &bin_root, prefix);
+    }
+
+    pub(crate) fn maybe_download_ci_llvm(&self) {
+        if !self.llvm_from_ci {
+            return;
+        }
+        let llvm_root = self.ci_llvm_root();
+        let llvm_stamp = llvm_root.join(".llvm-stamp");
+        let llvm_sha = detect_llvm_sha(&self, self.rust_info.is_managed_git_subrepository());
+        let key = format!("{}{}", llvm_sha, self.llvm_assertions);
+        if program_out_of_date(&llvm_stamp, &key) && !self.dry_run() {
+            self.download_ci_llvm(&llvm_sha);
+            for entry in t!(fs::read_dir(llvm_root.join("bin"))) {
+                self.fix_bin_or_dylib(&t!(entry).path());
+            }
+
+            // Update the timestamp of llvm-config to force rustc_llvm to be
+            // rebuilt. This is a hacky workaround for a deficiency in Cargo where
+            // the rerun-if-changed directive doesn't handle changes very well.
+            // https://github.com/rust-lang/cargo/issues/10791
+            // Cargo only compares the timestamp of the file relative to the last
+            // time `rustc_llvm` build script ran. However, the timestamps of the
+            // files in the tarball are in the past, so it doesn't trigger a
+            // rebuild.
+            let now = filetime::FileTime::from_system_time(std::time::SystemTime::now());
+            let llvm_config = llvm_root.join("bin").join(exe("llvm-config", self.build));
+            t!(filetime::set_file_times(&llvm_config, now, now));
+
+            let llvm_lib = llvm_root.join("lib");
+            for entry in t!(fs::read_dir(&llvm_lib)) {
+                let lib = t!(entry).path();
+                if lib.extension().map_or(false, |ext| ext == "so") {
+                    self.fix_bin_or_dylib(&lib);
+                }
+            }
+            t!(fs::write(llvm_stamp, key));
+        }
+    }
+
+    fn download_ci_llvm(&self, llvm_sha: &str) {
+        let llvm_assertions = self.llvm_assertions;
+
+        let cache_prefix = format!("llvm-{}-{}", llvm_sha, llvm_assertions);
+        let cache_dst = self.out.join("cache");
+        let rustc_cache = cache_dst.join(cache_prefix);
+        if !rustc_cache.exists() {
+            t!(fs::create_dir_all(&rustc_cache));
+        }
+        let base = if llvm_assertions {
+            &self.stage0_metadata.config.artifacts_with_llvm_assertions_server
+        } else {
+            &self.stage0_metadata.config.artifacts_server
+        };
+        let version = self.artifact_version_part(llvm_sha);
+        let filename = format!("rust-dev-{}-{}.tar.xz", version, self.build.triple);
+        let tarball = rustc_cache.join(&filename);
+        if !tarball.exists() {
+            let help_on_error = "error: failed to download llvm from ci
+
+    help: old builds get deleted after a certain time
+    help: if trying to compile an old commit of rustc, disable `download-ci-llvm` in config.toml:
+
+    [llvm]
+    download-ci-llvm = false
+    ";
+            self.download_file(&format!("{base}/{llvm_sha}/{filename}"), &tarball, help_on_error);
+        }
+        let llvm_root = self.ci_llvm_root();
+        self.unpack(&tarball, &llvm_root, "rust-dev");
+    }
+}
diff --git a/src/bootstrap/flags.rs b/src/bootstrap/flags.rs
index ee341a353ac4..2001e29bd2ea 100644
--- a/src/bootstrap/flags.rs
+++ b/src/bootstrap/flags.rs
@@ -140,6 +140,7 @@ pub enum Subcommand {
     },
     Run {
         paths: Vec<PathBuf>,
+        args: Vec<String>,
     },
     Setup {
         profile: Profile,
@@ -342,6 +343,9 @@ To learn more about a subcommand, run `./x.py <subcommand> -h`",
             Kind::Format => {
                 opts.optflag("", "check", "check formatting instead of applying.");
             }
+            Kind::Run => {
+                opts.optmulti("", "args", "arguments for the tool", "ARGS");
+            }
             _ => {}
         };
 
@@ -613,7 +617,7 @@ Arguments:
                     println!("\nrun requires at least a path!\n");
                     usage(1, &opts, verbose, &subcommand_help);
                 }
-                Subcommand::Run { paths }
+                Subcommand::Run { paths, args: matches.opt_strs("args") }
             }
             Kind::Setup => {
                 let profile = if paths.len() > 1 {
@@ -721,16 +725,12 @@ impl Subcommand {
     }
 
     pub fn test_args(&self) -> Vec<&str> {
-        let mut args = vec![];
-
         match *self {
             Subcommand::Test { ref test_args, .. } | Subcommand::Bench { ref test_args, .. } => {
-                args.extend(test_args.iter().flat_map(|s| s.split_whitespace()))
+                test_args.iter().flat_map(|s| s.split_whitespace()).collect()
             }
-            _ => (),
+            _ => vec![],
         }
-
-        args
     }
 
     pub fn rustc_args(&self) -> Vec<&str> {
@@ -738,7 +738,16 @@ impl Subcommand {
             Subcommand::Test { ref rustc_args, .. } => {
                 rustc_args.iter().flat_map(|s| s.split_whitespace()).collect()
             }
-            _ => Vec::new(),
+            _ => vec![],
+        }
+    }
+
+    pub fn args(&self) -> Vec<&str> {
+        match *self {
+            Subcommand::Run { ref args, .. } => {
+                args.iter().flat_map(|s| s.split_whitespace()).collect()
+            }
+            _ => vec![],
         }
     }
 
diff --git a/src/bootstrap/format.rs b/src/bootstrap/format.rs
index 37322670e656..5e7264fe765a 100644
--- a/src/bootstrap/format.rs
+++ b/src/bootstrap/format.rs
@@ -43,7 +43,7 @@ struct RustfmtConfig {
 }
 
 pub fn format(build: &Builder<'_>, check: bool, paths: &[PathBuf]) {
-    if build.config.dry_run {
+    if build.config.dry_run() {
         return;
     }
     let mut builder = ignore::types::TypesBuilder::new();
diff --git a/src/bootstrap/lib.rs b/src/bootstrap/lib.rs
index 7e70e99bb8ca..f4fa556b9745 100644
--- a/src/bootstrap/lib.rs
+++ b/src/bootstrap/lib.rs
@@ -112,15 +112,14 @@ use std::path::{Path, PathBuf};
 use std::process::Command;
 use std::str;
 
-use config::Target;
+use channel::GitInfo;
+use config::{DryRun, Target};
 use filetime::FileTime;
 use once_cell::sync::OnceCell;
 
 use crate::builder::Kind;
 use crate::config::{LlvmLibunwind, TargetSelection};
-use crate::util::{
-    check_run, exe, libdir, mtime, output, run, run_suppressed, try_run, try_run_suppressed, CiEnv,
-};
+use crate::util::{exe, libdir, mtime, output, run, run_suppressed, try_run_suppressed, CiEnv};
 
 mod bolt;
 mod builder;
@@ -133,6 +132,7 @@ mod compile;
 mod config;
 mod dist;
 mod doc;
+mod download;
 mod flags;
 mod format;
 mod install;
@@ -281,7 +281,6 @@ pub struct Build {
     src: PathBuf,
     out: PathBuf,
     bootstrap_out: PathBuf,
-    rust_info: channel::GitInfo,
     cargo_info: channel::GitInfo,
     rust_analyzer_info: channel::GitInfo,
     clippy_info: channel::GitInfo,
@@ -396,6 +395,28 @@ pub enum CLang {
     Cxx,
 }
 
+macro_rules! forward {
+    ( $( $fn:ident( $($param:ident: $ty:ty),* ) $( -> $ret:ty)? ),+ $(,)? ) => {
+        impl Build {
+            $( fn $fn(&self, $($param: $ty),* ) $( -> $ret)? {
+                self.config.$fn( $($param),* )
+            } )+
+        }
+    }
+}
+
+forward! {
+    verbose(msg: &str),
+    is_verbose() -> bool,
+    create(path: &Path, s: &str),
+    remove(f: &Path),
+    tempdir() -> PathBuf,
+    try_run(cmd: &mut Command) -> bool,
+    llvm_link_shared() -> bool,
+    download_rustc() -> bool,
+    initial_rustfmt() -> Option<PathBuf>,
+}
+
 impl Build {
     /// Creates a new set of build configuration from the `flags` on the command
     /// line and the filesystem `config`.
@@ -430,7 +451,7 @@ impl Build {
         // we always try to use git for LLVM builds
         let in_tree_llvm_info = channel::GitInfo::new(false, &src.join("src/llvm-project"));
 
-        let initial_target_libdir_str = if config.dry_run {
+        let initial_target_libdir_str = if config.dry_run() {
             "/dummy/lib/path/to/lib/".to_string()
         } else {
             output(
@@ -444,7 +465,7 @@ impl Build {
         let initial_target_dir = Path::new(&initial_target_libdir_str).parent().unwrap();
         let initial_lld = initial_target_dir.join("bin").join("rust-lld");
 
-        let initial_sysroot = if config.dry_run {
+        let initial_sysroot = if config.dry_run() {
             "/dummy".to_string()
         } else {
             output(Command::new(&config.initial_rustc).arg("--print").arg("sysroot"))
@@ -499,7 +520,6 @@ impl Build {
             out,
             bootstrap_out,
 
-            rust_info,
             cargo_info,
             rust_analyzer_info,
             clippy_info,
@@ -570,7 +590,7 @@ impl Build {
             t!(std::fs::read_dir(dir)).next().is_none()
         }
 
-        if !self.config.submodules(&self.rust_info) {
+        if !self.config.submodules(&self.rust_info()) {
             return;
         }
 
@@ -636,7 +656,7 @@ impl Build {
     /// This avoids contributors checking in a submodule change by accident.
     pub fn maybe_update_submodules(&self) {
         // Avoid running git when there isn't a git checkout.
-        if !self.config.submodules(&self.rust_info) {
+        if !self.config.submodules(&self.rust_info()) {
             return;
         }
         let output = output(
@@ -689,13 +709,13 @@ impl Build {
             }
         }
 
-        if !self.config.dry_run {
+        if !self.config.dry_run() {
             {
-                self.config.dry_run = true;
+                self.config.dry_run = DryRun::SelfCheck;
                 let builder = builder::Builder::new(&self);
                 builder.execute_cli();
             }
-            self.config.dry_run = false;
+            self.config.dry_run = DryRun::Disabled;
             let builder = builder::Builder::new(&self);
             builder.execute_cli();
         } else {
@@ -735,6 +755,10 @@ impl Build {
         cleared
     }
 
+    fn rust_info(&self) -> &GitInfo {
+        &self.config.rust_info
+    }
+
     /// Gets the space-separated set of activated features for the standard
     /// library.
     fn std_features(&self, target: TargetSelection) -> String {
@@ -947,7 +971,7 @@ impl Build {
 
     /// Runs a command, printing out nice contextual information if it fails.
     fn run(&self, cmd: &mut Command) {
-        if self.config.dry_run {
+        if self.config.dry_run() {
             return;
         }
         self.verbose(&format!("running: {:?}", cmd));
@@ -956,57 +980,24 @@ impl Build {
 
     /// Runs a command, printing out nice contextual information if it fails.
     fn run_quiet(&self, cmd: &mut Command) {
-        if self.config.dry_run {
+        if self.config.dry_run() {
             return;
         }
         self.verbose(&format!("running: {:?}", cmd));
         run_suppressed(cmd)
     }
 
-    /// Runs a command, printing out nice contextual information if it fails.
-    /// Exits if the command failed to execute at all, otherwise returns its
-    /// `status.success()`.
-    fn try_run(&self, cmd: &mut Command) -> bool {
-        if self.config.dry_run {
-            return true;
-        }
-        self.verbose(&format!("running: {:?}", cmd));
-        try_run(cmd, self.is_verbose())
-    }
-
     /// Runs a command, printing out nice contextual information if it fails.
     /// Exits if the command failed to execute at all, otherwise returns its
     /// `status.success()`.
     fn try_run_quiet(&self, cmd: &mut Command) -> bool {
-        if self.config.dry_run {
+        if self.config.dry_run() {
             return true;
         }
         self.verbose(&format!("running: {:?}", cmd));
         try_run_suppressed(cmd)
     }
 
-    /// Runs a command, printing out nice contextual information if it fails.
-    /// Returns false if do not execute at all, otherwise returns its
-    /// `status.success()`.
-    fn check_run(&self, cmd: &mut Command) -> bool {
-        if self.config.dry_run {
-            return true;
-        }
-        self.verbose(&format!("running: {:?}", cmd));
-        check_run(cmd, self.is_verbose())
-    }
-
-    pub fn is_verbose(&self) -> bool {
-        self.verbosity > 0
-    }
-
-    /// Prints a message if this build is configured in verbose mode.
-    fn verbose(&self, msg: &str) {
-        if self.is_verbose() {
-            println!("{}", msg);
-        }
-    }
-
     pub fn is_verbose_than(&self, level: usize) -> bool {
         self.verbosity > level
     }
@@ -1019,10 +1010,12 @@ impl Build {
     }
 
     fn info(&self, msg: &str) {
-        if self.config.dry_run {
-            return;
+        match self.config.dry_run {
+            DryRun::SelfCheck => return,
+            DryRun::Disabled | DryRun::UserSelected => {
+                println!("{}", msg);
+            }
         }
-        println!("{}", msg);
     }
 
     /// Returns the number of parallel jobs that have been configured for this
@@ -1152,8 +1145,8 @@ impl Build {
                 options[0] = Some("-Clink-arg=-fuse-ld=lld".to_string());
             }
 
-            let threads = if target.contains("windows") { "/threads:1" } else { "--threads=1" };
-            options[1] = Some(format!("-Clink-arg=-Wl,{}", threads));
+            let no_threads = util::lld_flag_no_threads(target.contains("windows"));
+            options[1] = Some(format!("-Clink-arg=-Wl,{}", no_threads));
         }
 
         IntoIterator::into_iter(options).flatten()
@@ -1267,7 +1260,7 @@ impl Build {
         match &self.config.channel[..] {
             "stable" => num.to_string(),
             "beta" => {
-                if self.rust_info.is_managed_git_subrepository() && !self.config.ignore_git {
+                if self.rust_info().is_managed_git_subrepository() && !self.config.ignore_git {
                     format!("{}-beta.{}", num, self.beta_prerelease_version())
                 } else {
                     format!("{}-beta", num)
@@ -1327,7 +1320,7 @@ impl Build {
     /// Note that this is a descriptive string which includes the commit date,
     /// sha, version, etc.
     fn rust_version(&self) -> String {
-        let mut version = self.rust_info.version(self, &self.version);
+        let mut version = self.rust_info().version(self, &self.version);
         if let Some(ref s) = self.config.description {
             version.push_str(" (");
             version.push_str(s);
@@ -1338,7 +1331,7 @@ impl Build {
 
     /// Returns the full commit hash.
     fn rust_sha(&self) -> Option<&str> {
-        self.rust_info.sha()
+        self.rust_info().sha()
     }
 
     /// Returns the `a.b.c` version that the given package is at.
@@ -1400,7 +1393,7 @@ impl Build {
     }
 
     fn read_stamp_file(&self, stamp: &Path) -> Vec<(PathBuf, DependencyType)> {
-        if self.config.dry_run {
+        if self.config.dry_run() {
             return Vec::new();
         }
 
@@ -1424,23 +1417,13 @@ impl Build {
         paths
     }
 
-    /// Create a temporary directory in `out` and return its path.
-    ///
-    /// NOTE: this temporary directory is shared between all steps;
-    /// if you need an empty directory, create a new subdirectory inside it.
-    fn tempdir(&self) -> PathBuf {
-        let tmp = self.out.join("tmp");
-        t!(fs::create_dir_all(&tmp));
-        tmp
-    }
-
     /// Copies a file from `src` to `dst`
     pub fn copy(&self, src: &Path, dst: &Path) {
         self.copy_internal(src, dst, false);
     }
 
     fn copy_internal(&self, src: &Path, dst: &Path, dereference_symlinks: bool) {
-        if self.config.dry_run {
+        if self.config.dry_run() {
             return;
         }
         self.verbose_than(1, &format!("Copy {:?} to {:?}", src, dst));
@@ -1477,7 +1460,7 @@ impl Build {
     /// Copies the `src` directory recursively to `dst`. Both are assumed to exist
     /// when this function is called.
     pub fn cp_r(&self, src: &Path, dst: &Path) {
-        if self.config.dry_run {
+        if self.config.dry_run() {
             return;
         }
         for f in self.read_dir(src) {
@@ -1530,7 +1513,7 @@ impl Build {
     }
 
     fn install(&self, src: &Path, dstdir: &Path, perms: u32) {
-        if self.config.dry_run {
+        if self.config.dry_run() {
             return;
         }
         let dst = dstdir.join(src.file_name().unwrap());
@@ -1543,29 +1526,22 @@ impl Build {
         chmod(&dst, perms);
     }
 
-    fn create(&self, path: &Path, s: &str) {
-        if self.config.dry_run {
-            return;
-        }
-        t!(fs::write(path, s));
-    }
-
     fn read(&self, path: &Path) -> String {
-        if self.config.dry_run {
+        if self.config.dry_run() {
             return String::new();
         }
         t!(fs::read_to_string(path))
     }
 
     fn create_dir(&self, dir: &Path) {
-        if self.config.dry_run {
+        if self.config.dry_run() {
             return;
         }
         t!(fs::create_dir_all(dir))
     }
 
     fn remove_dir(&self, dir: &Path) {
-        if self.config.dry_run {
+        if self.config.dry_run() {
             return;
         }
         t!(fs::remove_dir_all(dir))
@@ -1574,7 +1550,7 @@ impl Build {
     fn read_dir(&self, dir: &Path) -> impl Iterator<Item = fs::DirEntry> {
         let iter = match fs::read_dir(dir) {
             Ok(v) => v,
-            Err(_) if self.config.dry_run => return vec![].into_iter(),
+            Err(_) if self.config.dry_run() => return vec![].into_iter(),
             Err(err) => panic!("could not read dir {:?}: {:?}", dir, err),
         };
         iter.map(|e| t!(e)).collect::<Vec<_>>().into_iter()
@@ -1585,14 +1561,7 @@ impl Build {
         use std::os::unix::fs::symlink as symlink_file;
         #[cfg(windows)]
         use std::os::windows::fs::symlink_file;
-        if !self.config.dry_run { symlink_file(src.as_ref(), link.as_ref()) } else { Ok(()) }
-    }
-
-    fn remove(&self, f: &Path) {
-        if self.config.dry_run {
-            return;
-        }
-        fs::remove_file(f).unwrap_or_else(|_| panic!("failed to remove {:?}", f));
+        if !self.config.dry_run() { symlink_file(src.as_ref(), link.as_ref()) } else { Ok(()) }
     }
 
     /// Returns if config.ninja is enabled, and checks for ninja existence,
diff --git a/src/bootstrap/native.rs b/src/bootstrap/native.rs
index 2f856c2761cf..f6c453ebe107 100644
--- a/src/bootstrap/native.rs
+++ b/src/bootstrap/native.rs
@@ -19,9 +19,9 @@ use std::process::Command;
 use crate::bolt::{instrument_with_bolt_inplace, optimize_library_with_bolt_inplace};
 use crate::builder::{Builder, RunConfig, ShouldRun, Step};
 use crate::channel;
-use crate::config::TargetSelection;
+use crate::config::{Config, TargetSelection};
 use crate::util::get_clang_cl_resource_dir;
-use crate::util::{self, exe, output, program_out_of_date, t, up_to_date};
+use crate::util::{self, exe, output, t, up_to_date};
 use crate::{CLang, GitRepo};
 
 pub struct Meta {
@@ -65,7 +65,7 @@ pub fn prebuilt_llvm_config(
     builder: &Builder<'_>,
     target: TargetSelection,
 ) -> Result<PathBuf, Meta> {
-    maybe_download_ci_llvm(builder);
+    builder.config.maybe_download_ci_llvm();
 
     // If we're using a custom LLVM bail out here, but we can only use a
     // custom LLVM for the build triple.
@@ -117,7 +117,7 @@ pub fn prebuilt_llvm_config(
 }
 
 /// This retrieves the LLVM sha we *want* to use, according to git history.
-pub(crate) fn detect_llvm_sha(config: &crate::config::Config, is_git: bool) -> String {
+pub(crate) fn detect_llvm_sha(config: &Config, is_git: bool) -> String {
     let llvm_sha = if is_git {
         let mut rev_list = config.git();
         rev_list.args(&[
@@ -155,7 +155,7 @@ pub(crate) fn detect_llvm_sha(config: &crate::config::Config, is_git: bool) -> S
 /// This checks both the build triple platform to confirm we're usable at all,
 /// and then verifies if the current HEAD matches the detected LLVM SHA head,
 /// in which case LLVM is indicated as not available.
-pub(crate) fn is_ci_llvm_available(config: &crate::config::Config, asserts: bool) -> bool {
+pub(crate) fn is_ci_llvm_available(config: &Config, asserts: bool) -> bool {
     // This is currently all tier 1 targets and tier 2 targets with host tools
     // (since others may not have CI artifacts)
     // https://doc.rust-lang.org/rustc/platform-support.html#tier-1
@@ -217,80 +217,6 @@ pub(crate) fn is_ci_llvm_available(config: &crate::config::Config, asserts: bool
     true
 }
 
-pub(crate) fn maybe_download_ci_llvm(builder: &Builder<'_>) {
-    let config = &builder.config;
-    if !config.llvm_from_ci {
-        return;
-    }
-    let llvm_root = config.ci_llvm_root();
-    let llvm_stamp = llvm_root.join(".llvm-stamp");
-    let llvm_sha = detect_llvm_sha(&config, builder.rust_info.is_managed_git_subrepository());
-    let key = format!("{}{}", llvm_sha, config.llvm_assertions);
-    if program_out_of_date(&llvm_stamp, &key) && !config.dry_run {
-        download_ci_llvm(builder, &llvm_sha);
-        for entry in t!(fs::read_dir(llvm_root.join("bin"))) {
-            builder.fix_bin_or_dylib(&t!(entry).path());
-        }
-
-        // Update the timestamp of llvm-config to force rustc_llvm to be
-        // rebuilt. This is a hacky workaround for a deficiency in Cargo where
-        // the rerun-if-changed directive doesn't handle changes very well.
-        // https://github.com/rust-lang/cargo/issues/10791
-        // Cargo only compares the timestamp of the file relative to the last
-        // time `rustc_llvm` build script ran. However, the timestamps of the
-        // files in the tarball are in the past, so it doesn't trigger a
-        // rebuild.
-        let now = filetime::FileTime::from_system_time(std::time::SystemTime::now());
-        let llvm_config = llvm_root.join("bin").join(exe("llvm-config", builder.config.build));
-        t!(filetime::set_file_times(&llvm_config, now, now));
-
-        let llvm_lib = llvm_root.join("lib");
-        for entry in t!(fs::read_dir(&llvm_lib)) {
-            let lib = t!(entry).path();
-            if lib.extension().map_or(false, |ext| ext == "so") {
-                builder.fix_bin_or_dylib(&lib);
-            }
-        }
-        t!(fs::write(llvm_stamp, key));
-    }
-}
-
-fn download_ci_llvm(builder: &Builder<'_>, llvm_sha: &str) {
-    let llvm_assertions = builder.config.llvm_assertions;
-
-    let cache_prefix = format!("llvm-{}-{}", llvm_sha, llvm_assertions);
-    let cache_dst = builder.out.join("cache");
-    let rustc_cache = cache_dst.join(cache_prefix);
-    if !rustc_cache.exists() {
-        t!(fs::create_dir_all(&rustc_cache));
-    }
-    let base = if llvm_assertions {
-        &builder.config.stage0_metadata.config.artifacts_with_llvm_assertions_server
-    } else {
-        &builder.config.stage0_metadata.config.artifacts_server
-    };
-    let channel = builder.config.artifact_channel(builder, llvm_sha);
-    let filename = format!("rust-dev-{}-{}.tar.xz", channel, builder.build.build.triple);
-    let tarball = rustc_cache.join(&filename);
-    if !tarball.exists() {
-        let help_on_error = "error: failed to download llvm from ci
-
-help: old builds get deleted after a certain time
-help: if trying to compile an old commit of rustc, disable `download-ci-llvm` in config.toml:
-
-[llvm]
-download-ci-llvm = false
-";
-        builder.download_component(
-            &format!("{base}/{llvm_sha}/{filename}"),
-            &tarball,
-            help_on_error,
-        );
-    }
-    let llvm_root = builder.config.ci_llvm_root();
-    builder.unpack(&tarball, &llvm_root, "rust-dev");
-}
-
 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
 pub struct Llvm {
     pub target: TargetSelection,
@@ -505,7 +431,7 @@ impl Step for Llvm {
         // https://llvm.org/docs/HowToCrossCompileLLVM.html
         if target != builder.config.build {
             let llvm_config = builder.ensure(Llvm { target: builder.config.build });
-            if !builder.config.dry_run {
+            if !builder.config.dry_run() {
                 let llvm_bindir = output(Command::new(&llvm_config).arg("--bindir"));
                 let host_bin = Path::new(llvm_bindir.trim());
                 cfg.define(
@@ -519,7 +445,7 @@ impl Step for Llvm {
             if builder.config.llvm_clang {
                 let build_bin = builder.llvm_out(builder.config.build).join("build").join("bin");
                 let clang_tblgen = build_bin.join("clang-tblgen").with_extension(EXE_EXTENSION);
-                if !builder.config.dry_run && !clang_tblgen.exists() {
+                if !builder.config.dry_run() && !clang_tblgen.exists() {
                     panic!("unable to find {}", clang_tblgen.display());
                 }
                 cfg.define("CLANG_TABLEGEN", clang_tblgen);
@@ -553,7 +479,7 @@ impl Step for Llvm {
         //        tools. Figure out how to filter them down and only build the right
         //        tools and libs on all platforms.
 
-        if builder.config.dry_run {
+        if builder.config.dry_run() {
             return build_llvm_config;
         }
 
@@ -611,7 +537,7 @@ fn check_llvm_version(builder: &Builder<'_>, llvm_config: &Path) {
         return;
     }
 
-    if builder.config.dry_run {
+    if builder.config.dry_run() {
         return;
     }
 
@@ -872,7 +798,7 @@ impl Step for Lld {
 
     /// Compile LLD for `target`.
     fn run(self, builder: &Builder<'_>) -> PathBuf {
-        if builder.config.dry_run {
+        if builder.config.dry_run() {
             return PathBuf::from("lld-out-dir-test-gen");
         }
         let target = self.target;
@@ -990,7 +916,7 @@ impl Step for TestHelpers {
     /// Compiles the `rust_test_helpers.c` library which we used in various
     /// `run-pass` tests for ABI testing.
     fn run(self, builder: &Builder<'_>) {
-        if builder.config.dry_run {
+        if builder.config.dry_run() {
             return;
         }
         // The x86_64-fortanix-unknown-sgx target doesn't have a working C
@@ -1066,7 +992,7 @@ impl Step for Sanitizers {
         }
 
         let llvm_config = builder.ensure(Llvm { target: builder.config.build });
-        if builder.config.dry_run {
+        if builder.config.dry_run() {
             return runtimes;
         }
 
@@ -1240,7 +1166,7 @@ impl Step for CrtBeginEnd {
     fn run(self, builder: &Builder<'_>) -> Self::Output {
         let out_dir = builder.native_dir(self.target).join("crt");
 
-        if builder.config.dry_run {
+        if builder.config.dry_run() {
             return out_dir;
         }
 
@@ -1304,7 +1230,7 @@ impl Step for Libunwind {
 
     /// Build linunwind.a
     fn run(self, builder: &Builder<'_>) -> Self::Output {
-        if builder.config.dry_run {
+        if builder.config.dry_run() {
             return PathBuf::new();
         }
 
diff --git a/src/bootstrap/run.rs b/src/bootstrap/run.rs
index 511872903d14..d49b41c51327 100644
--- a/src/bootstrap/run.rs
+++ b/src/bootstrap/run.rs
@@ -1,9 +1,13 @@
-use crate::builder::{Builder, RunConfig, ShouldRun, Step};
-use crate::dist::distdir;
-use crate::tool::Tool;
-use crate::util::output;
 use std::process::Command;
 
+use crate::builder::{Builder, RunConfig, ShouldRun, Step};
+use crate::config::TargetSelection;
+use crate::dist::distdir;
+use crate::test;
+use crate::tool::{self, SourceType, Tool};
+use crate::util::output;
+use crate::Mode;
+
 #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
 pub struct ExpandYamlAnchors;
 
@@ -125,3 +129,63 @@ impl Step for ReplaceVersionPlaceholder {
         builder.run(&mut cmd);
     }
 }
+
+#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
+pub struct Miri {
+    stage: u32,
+    host: TargetSelection,
+    target: TargetSelection,
+}
+
+impl Step for Miri {
+    type Output = ();
+    const ONLY_HOSTS: bool = false;
+
+    fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
+        run.path("src/tools/miri")
+    }
+
+    fn make_run(run: RunConfig<'_>) {
+        run.builder.ensure(Miri {
+            stage: run.builder.top_stage,
+            host: run.build_triple(),
+            target: run.target,
+        });
+    }
+
+    fn run(self, builder: &Builder<'_>) {
+        let stage = self.stage;
+        let host = self.host;
+        let target = self.target;
+        let compiler = builder.compiler(stage, host);
+
+        let miri = builder
+            .ensure(tool::Miri { compiler, target: self.host, extra_features: Vec::new() })
+            .expect("in-tree tool");
+        let miri_sysroot = test::Miri::build_miri_sysroot(builder, compiler, &miri, target);
+
+        // # Run miri.
+        // Running it via `cargo run` as that figures out the right dylib path.
+        // add_rustc_lib_path does not add the path that contains librustc_driver-<...>.so.
+        let mut miri = tool::prepare_tool_cargo(
+            builder,
+            compiler,
+            Mode::ToolRustc,
+            host,
+            "run",
+            "src/tools/miri",
+            SourceType::InTree,
+            &[],
+        );
+        miri.add_rustc_lib_path(builder, compiler);
+        // Forward arguments.
+        miri.arg("--").arg("--target").arg(target.rustc_target_arg());
+        miri.args(builder.config.cmd.args());
+
+        // miri tests need to know about the stage sysroot
+        miri.env("MIRI_SYSROOT", &miri_sysroot);
+
+        let mut miri = Command::from(miri);
+        builder.run(&mut miri);
+    }
+}
diff --git a/src/bootstrap/sanity.rs b/src/bootstrap/sanity.rs
index e905517253c0..631d42acb93f 100644
--- a/src/bootstrap/sanity.rs
+++ b/src/bootstrap/sanity.rs
@@ -74,7 +74,7 @@ pub fn check(build: &mut Build) {
     let mut cmd_finder = Finder::new();
     // If we've got a git directory we're gonna need git to update
     // submodules and learn about various other aspects.
-    if build.rust_info.is_managed_git_subrepository() {
+    if build.rust_info().is_managed_git_subrepository() {
         cmd_finder.must_have("git");
     }
 
@@ -155,7 +155,15 @@ than building it.
             continue;
         }
 
-        if !build.config.dry_run {
+        // Some environments don't want or need these tools, such as when testing Miri.
+        // FIXME: it would be better to refactor this code to split necessary setup from pure sanity
+        // checks, and have a regular flag for skipping the latter. Also see
+        // <https://github.com/rust-lang/rust/pull/103569#discussion_r1008741742>.
+        if env::var_os("BOOTSTRAP_SKIP_TARGET_SANITY").is_some() {
+            continue;
+        }
+
+        if !build.config.dry_run() {
             cmd_finder.must_have(build.cc(*target));
             if let Some(ar) = build.ar(*target) {
                 cmd_finder.must_have(ar);
@@ -164,7 +172,7 @@ than building it.
     }
 
     for host in &build.hosts {
-        if !build.config.dry_run {
+        if !build.config.dry_run() {
             cmd_finder.must_have(build.cxx(*host).unwrap());
         }
     }
@@ -212,6 +220,14 @@ than building it.
             }
         }
 
+        // Some environments don't want or need these tools, such as when testing Miri.
+        // FIXME: it would be better to refactor this code to split necessary setup from pure sanity
+        // checks, and have a regular flag for skipping the latter. Also see
+        // <https://github.com/rust-lang/rust/pull/103569#discussion_r1008741742>.
+        if env::var_os("BOOTSTRAP_SKIP_TARGET_SANITY").is_some() {
+            continue;
+        }
+
         if need_cmake && target.contains("msvc") {
             // There are three builds of cmake on windows: MSVC, MinGW, and
             // Cygwin. The Cygwin build does not have generators for Visual
diff --git a/src/bootstrap/setup.rs b/src/bootstrap/setup.rs
index eb7da1bda73c..04480277fe04 100644
--- a/src/bootstrap/setup.rs
+++ b/src/bootstrap/setup.rs
@@ -82,7 +82,7 @@ impl fmt::Display for Profile {
 }
 
 pub fn setup(config: &Config, profile: Profile) {
-    let path = &config.config;
+    let path = &config.config.clone().unwrap_or(PathBuf::from("config.toml"));
 
     if path.exists() {
         eprintln!(
diff --git a/src/bootstrap/tarball.rs b/src/bootstrap/tarball.rs
index d999b6c15033..fc850a22b2f6 100644
--- a/src/bootstrap/tarball.rs
+++ b/src/bootstrap/tarball.rs
@@ -298,7 +298,7 @@ impl<'a> Tarball<'a> {
     fn run(self, build_cli: impl FnOnce(&Tarball<'a>, &mut Command)) -> GeneratedTarball {
         t!(std::fs::create_dir_all(&self.overlay_dir));
         self.builder.create(&self.overlay_dir.join("version"), &self.overlay.version(self.builder));
-        if let Some(info) = self.builder.rust_info.info() {
+        if let Some(info) = self.builder.rust_info().info() {
             channel::write_commit_hash_file(&self.overlay_dir, &info.sha);
             channel::write_commit_info_file(&self.overlay_dir, info);
         }
@@ -323,7 +323,7 @@ impl<'a> Tarball<'a> {
         // Ensure there are no symbolic links in the tarball. In particular,
         // rustup-toolchain-install-master and most versions of Windows can't handle symbolic links.
         let decompressed_output = self.temp_dir.join(&package_name);
-        if !self.builder.config.dry_run && !self.permit_symlinks {
+        if !self.builder.config.dry_run() && !self.permit_symlinks {
             for entry in walkdir::WalkDir::new(&decompressed_output) {
                 let entry = t!(entry);
                 if entry.path_is_symlink() {
diff --git a/src/bootstrap/test.rs b/src/bootstrap/test.rs
index 8d4914097787..fd362b8367cc 100644
--- a/src/bootstrap/test.rs
+++ b/src/bootstrap/test.rs
@@ -16,6 +16,7 @@ use crate::cache::Interned;
 use crate::compile;
 use crate::config::TargetSelection;
 use crate::dist;
+use crate::doc::DocumentationFormat;
 use crate::flags::Subcommand;
 use crate::native;
 use crate::tool::{self, SourceType, Tool};
@@ -461,24 +462,90 @@ impl Step for RustDemangler {
 pub struct Miri {
     stage: u32,
     host: TargetSelection,
+    target: TargetSelection,
+}
+
+impl Miri {
+    /// Run `cargo miri setup` for the given target, return where the Miri sysroot was put.
+    pub fn build_miri_sysroot(
+        builder: &Builder<'_>,
+        compiler: Compiler,
+        miri: &Path,
+        target: TargetSelection,
+    ) -> String {
+        let miri_sysroot = builder.out.join(compiler.host.triple).join("miri-sysrot");
+        let mut cargo = tool::prepare_tool_cargo(
+            builder,
+            compiler,
+            Mode::ToolRustc,
+            compiler.host,
+            "run",
+            "src/tools/miri/cargo-miri",
+            SourceType::InTree,
+            &[],
+        );
+        cargo.add_rustc_lib_path(builder, compiler);
+        cargo.arg("--").arg("miri").arg("setup");
+        cargo.arg("--target").arg(target.rustc_target_arg());
+
+        // Tell `cargo miri setup` where to find the sources.
+        cargo.env("MIRI_LIB_SRC", builder.src.join("library"));
+        // Tell it where to find Miri.
+        cargo.env("MIRI", &miri);
+        // Tell it where to put the sysroot.
+        cargo.env("MIRI_SYSROOT", &miri_sysroot);
+        // Debug things.
+        cargo.env("RUST_BACKTRACE", "1");
+
+        let mut cargo = Command::from(cargo);
+        builder.run(&mut cargo);
+
+        // # Determine where Miri put its sysroot.
+        // To this end, we run `cargo miri setup --print-sysroot` and capture the output.
+        // (We do this separately from the above so that when the setup actually
+        // happens we get some output.)
+        // We re-use the `cargo` from above.
+        cargo.arg("--print-sysroot");
+
+        // FIXME: Is there a way in which we can re-use the usual `run` helpers?
+        if builder.config.dry_run() {
+            String::new()
+        } else {
+            builder.verbose(&format!("running: {:?}", cargo));
+            let out =
+                cargo.output().expect("We already ran `cargo miri setup` before and that worked");
+            assert!(out.status.success(), "`cargo miri setup` returned with non-0 exit code");
+            // Output is "<sysroot>\n".
+            let stdout = String::from_utf8(out.stdout)
+                .expect("`cargo miri setup` stdout is not valid UTF-8");
+            let sysroot = stdout.trim_end();
+            builder.verbose(&format!("`cargo miri setup --print-sysroot` said: {:?}", sysroot));
+            sysroot.to_owned()
+        }
+    }
 }
 
 impl Step for Miri {
     type Output = ();
-    const ONLY_HOSTS: bool = true;
+    const ONLY_HOSTS: bool = false;
 
     fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
         run.path("src/tools/miri")
     }
 
     fn make_run(run: RunConfig<'_>) {
-        run.builder.ensure(Miri { stage: run.builder.top_stage, host: run.target });
+        run.builder.ensure(Miri {
+            stage: run.builder.top_stage,
+            host: run.build_triple(),
+            target: run.target,
+        });
     }
 
     /// Runs `cargo test` for miri.
     fn run(self, builder: &Builder<'_>) {
         let stage = self.stage;
         let host = self.host;
+        let target = self.target;
         let compiler = builder.compiler(stage, host);
         // We need the stdlib for the *next* stage, as it was built with this compiler that also built Miri.
         // Except if we are at stage 2, the bootstrap loop is complete and we can stick with our current stage.
@@ -494,8 +561,43 @@ impl Step for Miri {
         // sysroot does not seem to populate it, so we do that first.
         builder.ensure(compile::Std::new(compiler_std, host));
         let sysroot = builder.sysroot(compiler_std);
+        // We also need a Miri sysroot.
+        let miri_sysroot = Miri::build_miri_sysroot(builder, compiler, &miri, target);
 
-        // # Run `cargo miri setup`.
+        // # Run `cargo test`.
+        let mut cargo = tool::prepare_tool_cargo(
+            builder,
+            compiler,
+            Mode::ToolRustc,
+            host,
+            "test",
+            "src/tools/miri",
+            SourceType::InTree,
+            &[],
+        );
+        cargo.add_rustc_lib_path(builder, compiler);
+
+        // miri tests need to know about the stage sysroot
+        cargo.env("MIRI_SYSROOT", &miri_sysroot);
+        cargo.env("MIRI_HOST_SYSROOT", sysroot);
+        cargo.env("MIRI", &miri);
+        // propagate --bless
+        if builder.config.cmd.bless() {
+            cargo.env("MIRI_BLESS", "Gesundheit");
+        }
+
+        // Set the target.
+        cargo.env("MIRI_TEST_TARGET", target.rustc_target_arg());
+        // Forward test filters.
+        cargo.arg("--").args(builder.config.cmd.test_args());
+
+        let mut cargo = Command::from(cargo);
+        builder.run(&mut cargo);
+
+        // # Run `cargo miri test`.
+        // This is just a smoke test (Miri's own CI invokes this in a bunch of different ways and ensures
+        // that we get the desired output), but that is sufficient to make sure that the libtest harness
+        // itself executes properly under Miri.
         let mut cargo = tool::prepare_tool_cargo(
             builder,
             compiler,
@@ -507,68 +609,23 @@ impl Step for Miri {
             &[],
         );
         cargo.add_rustc_lib_path(builder, compiler);
-        cargo.arg("--").arg("miri").arg("setup");
+        cargo.arg("--").arg("miri").arg("test");
+        cargo
+            .arg("--manifest-path")
+            .arg(builder.src.join("src/tools/miri/test-cargo-miri/Cargo.toml"));
+        cargo.arg("--target").arg(target.rustc_target_arg());
+        cargo.arg("--tests"); // don't run doctests, they are too confused by the staging
+        cargo.arg("--").args(builder.config.cmd.test_args());
 
-        // Tell `cargo miri setup` where to find the sources.
-        cargo.env("MIRI_LIB_SRC", builder.src.join("library"));
-        // Tell it where to find Miri.
+        // Tell `cargo miri` where to find things.
+        cargo.env("MIRI_SYSROOT", &miri_sysroot);
+        cargo.env("MIRI_HOST_SYSROOT", sysroot);
         cargo.env("MIRI", &miri);
         // Debug things.
         cargo.env("RUST_BACKTRACE", "1");
 
         let mut cargo = Command::from(cargo);
         builder.run(&mut cargo);
-
-        // # Determine where Miri put its sysroot.
-        // To this end, we run `cargo miri setup --print-sysroot` and capture the output.
-        // (We do this separately from the above so that when the setup actually
-        // happens we get some output.)
-        // We re-use the `cargo` from above.
-        cargo.arg("--print-sysroot");
-
-        // FIXME: Is there a way in which we can re-use the usual `run` helpers?
-        let miri_sysroot = if builder.config.dry_run {
-            String::new()
-        } else {
-            builder.verbose(&format!("running: {:?}", cargo));
-            let out =
-                cargo.output().expect("We already ran `cargo miri setup` before and that worked");
-            assert!(out.status.success(), "`cargo miri setup` returned with non-0 exit code");
-            // Output is "<sysroot>\n".
-            let stdout = String::from_utf8(out.stdout)
-                .expect("`cargo miri setup` stdout is not valid UTF-8");
-            let sysroot = stdout.trim_end();
-            builder.verbose(&format!("`cargo miri setup --print-sysroot` said: {:?}", sysroot));
-            sysroot.to_owned()
-        };
-
-        // # Run `cargo test`.
-        let mut cargo = tool::prepare_tool_cargo(
-            builder,
-            compiler,
-            Mode::ToolRustc,
-            host,
-            "test",
-            "src/tools/miri",
-            SourceType::Submodule,
-            &[],
-        );
-        cargo.add_rustc_lib_path(builder, compiler);
-
-        // miri tests need to know about the stage sysroot
-        cargo.env("MIRI_SYSROOT", miri_sysroot);
-        cargo.env("MIRI_HOST_SYSROOT", sysroot);
-        cargo.env("RUSTC_LIB_PATH", builder.rustc_libdir(compiler));
-        cargo.env("MIRI", miri);
-        // propagate --bless
-        if builder.config.cmd.bless() {
-            cargo.env("MIRI_BLESS", "Gesundheit");
-        }
-
-        cargo.arg("--").args(builder.config.cmd.test_args());
-
-        let mut cargo = Command::from(cargo);
-        builder.run(&mut cargo);
     }
 }
 
@@ -727,7 +784,10 @@ impl Step for RustdocTheme {
             cmd.env("RUSTDOC_LINKER", linker);
         }
         if builder.is_fuse_ld_lld(self.compiler.host) {
-            cmd.env("RUSTDOC_FUSE_LD_LLD", "1");
+            cmd.env(
+                "RUSTDOC_LLD_NO_THREADS",
+                util::lld_flag_no_threads(self.compiler.host.contains("windows")),
+            );
         }
         try_run(builder, &mut cmd);
     }
@@ -775,7 +835,11 @@ impl Step for RustdocJSStd {
                     command.arg("--test-file").arg(path);
                 }
             }
-            builder.ensure(crate::doc::Std { target: self.target, stage: builder.top_stage });
+            builder.ensure(crate::doc::Std {
+                target: self.target,
+                stage: builder.top_stage,
+                format: DocumentationFormat::HTML,
+            });
             builder.run(&mut command);
         } else {
             builder.info("No nodejs found, skipping \"src/test/rustdoc-js-std\" tests");
@@ -939,6 +1003,7 @@ impl Step for RustdocGUI {
                     .arg("doc")
                     .arg("--target-dir")
                     .arg(&out_dir)
+                    .env("RUSTC_BOOTSTRAP", "1")
                     .env("RUSTDOC", builder.rustdoc(self.compiler))
                     .env("RUSTC", builder.rustc(self.compiler))
                     .current_dir(path);
@@ -1004,6 +1069,9 @@ impl Step for Tidy {
         if builder.is_verbose() {
             cmd.arg("--verbose");
         }
+        if builder.config.cmd.bless() {
+            cmd.arg("--bless");
+        }
 
         builder.info("tidy check");
         try_run(builder, &mut cmd);
@@ -1374,7 +1442,7 @@ note: if you're sure you want to do this, please open an issue as to why. In the
         }
         let mut flags = if is_rustdoc { Vec::new() } else { vec!["-Crpath".to_string()] };
         flags.push(format!("-Cdebuginfo={}", builder.config.rust_debuginfo_level_tests));
-        flags.push(builder.config.cmd.rustc_args().join(" "));
+        flags.extend(builder.config.cmd.rustc_args().iter().map(|s| s.to_string()));
 
         if let Some(linker) = builder.linker(target) {
             cmd.arg("--linker").arg(linker);
@@ -1383,12 +1451,16 @@ note: if you're sure you want to do this, please open an issue as to why. In the
         let mut hostflags = flags.clone();
         hostflags.push(format!("-Lnative={}", builder.test_helpers_out(compiler.host).display()));
         hostflags.extend(builder.lld_flags(compiler.host));
-        cmd.arg("--host-rustcflags").arg(hostflags.join(" "));
+        for flag in hostflags {
+            cmd.arg("--host-rustcflags").arg(flag);
+        }
 
         let mut targetflags = flags;
         targetflags.push(format!("-Lnative={}", builder.test_helpers_out(target).display()));
         targetflags.extend(builder.lld_flags(target));
-        cmd.arg("--target-rustcflags").arg(targetflags.join(" "));
+        for flag in targetflags {
+            cmd.arg("--target-rustcflags").arg(flag);
+        }
 
         cmd.arg("--python").arg(builder.python());
 
@@ -1465,7 +1537,7 @@ note: if you're sure you want to do this, please open an issue as to why. In the
         let mut copts_passed = false;
         if builder.config.llvm_enabled() {
             let llvm_config = builder.ensure(native::Llvm { target: builder.config.build });
-            if !builder.config.dry_run {
+            if !builder.config.dry_run() {
                 let llvm_version = output(Command::new(&llvm_config).arg("--version"));
                 let llvm_components = output(Command::new(&llvm_config).arg("--components"));
                 // Remove trailing newline from llvm-config output.
@@ -1483,14 +1555,14 @@ note: if you're sure you want to do this, please open an issue as to why. In the
             // requirement, but the `-L` library path is not propagated across
             // separate compilations. We can add LLVM's library path to the
             // platform-specific environment variable as a workaround.
-            if !builder.config.dry_run && suite.ends_with("fulldeps") {
+            if !builder.config.dry_run() && suite.ends_with("fulldeps") {
                 let llvm_libdir = output(Command::new(&llvm_config).arg("--libdir"));
                 add_link_lib_path(vec![llvm_libdir.trim().into()], &mut cmd);
             }
 
             // Only pass correct values for these flags for the `run-make` suite as it
             // requires that a C++ compiler was configured which isn't always the case.
-            if !builder.config.dry_run && matches!(suite, "run-make" | "run-make-fulldeps") {
+            if !builder.config.dry_run() && matches!(suite, "run-make" | "run-make-fulldeps") {
                 // The llvm/bin directory contains many useful cross-platform
                 // tools. Pass the path to run-make tests so they can use them.
                 let llvm_bin_path = llvm_config
@@ -1518,7 +1590,7 @@ note: if you're sure you want to do this, please open an issue as to why. In the
 
         // Only pass correct values for these flags for the `run-make` suite as it
         // requires that a C++ compiler was configured which isn't always the case.
-        if !builder.config.dry_run && matches!(suite, "run-make" | "run-make-fulldeps") {
+        if !builder.config.dry_run() && matches!(suite, "run-make" | "run-make-fulldeps") {
             cmd.arg("--cc")
                 .arg(builder.cc(target))
                 .arg("--cxx")
@@ -1674,6 +1746,8 @@ impl BookTest {
 
         let mut rustbook_cmd = builder.tool_cmd(Tool::Rustbook);
         let path = builder.src.join(&self.path);
+        // Books often have feature-gated example text.
+        rustbook_cmd.env("RUSTC_BOOTSTRAP", "1");
         rustbook_cmd.env("PATH", new_path).arg("test").arg(path);
         builder.add_rust_test_threads(&mut rustbook_cmd);
         builder.info(&format!("Testing rustbook {}", self.path.display()));
diff --git a/src/bootstrap/tool.rs b/src/bootstrap/tool.rs
index eec74b2675a1..ba329ea6c759 100644
--- a/src/bootstrap/tool.rs
+++ b/src/bootstrap/tool.rs
@@ -522,7 +522,7 @@ impl Step for Rustdoc {
         builder.ensure(compile::Rustc::new(build_compiler, target_compiler.host));
         // NOTE: this implies that `download-rustc` is pretty useless when compiling with the stage0
         // compiler, since you do just as much work.
-        if !builder.config.dry_run && builder.download_rustc() && build_compiler.stage == 0 {
+        if !builder.config.dry_run() && builder.download_rustc() && build_compiler.stage == 0 {
             println!(
                 "warning: `download-rustc` does nothing when building stage1 tools; consider using `--stage 2` instead"
             );
@@ -794,10 +794,9 @@ macro_rules! tool_extended {
        $($name:ident,
        $path:expr,
        $tool_name:expr,
-       stable = $stable:expr,
-       $(in_tree = $in_tree:expr,)?
-       $(tool_std = $tool_std:literal,)?
-       $extra_deps:block;)+) => {
+       stable = $stable:expr
+       $(,tool_std = $tool_std:literal)?
+       ;)+) => {
         $(
             #[derive(Debug, Clone, Hash, PartialEq, Eq)]
         pub struct $name {
@@ -839,7 +838,6 @@ macro_rules! tool_extended {
 
             #[allow(unused_mut)]
             fn run(mut $sel, $builder: &Builder<'_>) -> Option<PathBuf> {
-                $extra_deps
                 $builder.ensure(ToolBuild {
                     compiler: $sel.compiler,
                     target: $sel.target,
@@ -848,11 +846,7 @@ macro_rules! tool_extended {
                     path: $path,
                     extra_features: $sel.extra_features,
                     is_optional_tool: true,
-                    source_type: if false $(|| $in_tree)* {
-                        SourceType::InTree
-                    } else {
-                        SourceType::Submodule
-                    },
+                    source_type: SourceType::InTree,
                 })
             }
         }
@@ -865,17 +859,17 @@ macro_rules! tool_extended {
 // Note: Most submodule updates for tools are handled by bootstrap.py, since they're needed just to
 // invoke Cargo to build bootstrap. See the comment there for more details.
 tool_extended!((self, builder),
-    Cargofmt, "src/tools/rustfmt", "cargo-fmt", stable=true, in_tree=true, {};
-    CargoClippy, "src/tools/clippy", "cargo-clippy", stable=true, in_tree=true, {};
-    Clippy, "src/tools/clippy", "clippy-driver", stable=true, in_tree=true, {};
-    Miri, "src/tools/miri", "miri", stable=false, in_tree=true, {};
-    CargoMiri, "src/tools/miri/cargo-miri", "cargo-miri", stable=false, in_tree=true, {};
+    Cargofmt, "src/tools/rustfmt", "cargo-fmt", stable=true;
+    CargoClippy, "src/tools/clippy", "cargo-clippy", stable=true;
+    Clippy, "src/tools/clippy", "clippy-driver", stable=true;
+    Miri, "src/tools/miri", "miri", stable=false;
+    CargoMiri, "src/tools/miri/cargo-miri", "cargo-miri", stable=true;
     // FIXME: tool_std is not quite right, we shouldn't allow nightly features.
     // But `builder.cargo` doesn't know how to handle ToolBootstrap in stages other than 0,
     // and this is close enough for now.
-    Rls, "src/tools/rls", "rls", stable=true, in_tree=true, tool_std=true, {};
-    RustDemangler, "src/tools/rust-demangler", "rust-demangler", stable=false, in_tree=true, tool_std=true, {};
-    Rustfmt, "src/tools/rustfmt", "rustfmt", stable=true, in_tree=true, {};
+    Rls, "src/tools/rls", "rls", stable=true, tool_std=true;
+    RustDemangler, "src/tools/rust-demangler", "rust-demangler", stable=false, tool_std=true;
+    Rustfmt, "src/tools/rustfmt", "rustfmt", stable=true;
 );
 
 impl<'a> Builder<'a> {
diff --git a/src/bootstrap/toolstate.rs b/src/bootstrap/toolstate.rs
index 1a1774432275..1969e0b6f872 100644
--- a/src/bootstrap/toolstate.rs
+++ b/src/bootstrap/toolstate.rs
@@ -158,7 +158,7 @@ impl Step for ToolStateCheck {
     ///   stable tool. That is, the status is not allowed to get worse
     ///   (test-pass to test-fail or build-fail).
     fn run(self, builder: &Builder<'_>) {
-        if builder.config.dry_run {
+        if builder.config.dry_run() {
             return;
         }
 
@@ -265,7 +265,7 @@ impl Builder<'_> {
         // If we're in a dry run setting we don't want to save toolstates as
         // that means if we e.g. panic down the line it'll look like we tested
         // everything (but we actually haven't).
-        if self.config.dry_run {
+        if self.config.dry_run() {
             return;
         }
         // Toolstate isn't tracked for clippy or rustfmt, but since most tools do, we avoid checking
diff --git a/src/bootstrap/util.rs b/src/bootstrap/util.rs
index 0ebabbd5ca5c..58220783228b 100644
--- a/src/bootstrap/util.rs
+++ b/src/bootstrap/util.rs
@@ -13,6 +13,7 @@ use std::time::{Instant, SystemTime, UNIX_EPOCH};
 
 use crate::builder::Builder;
 use crate::config::{Config, TargetSelection};
+use crate::OnceCell;
 
 /// A helper macro to `unwrap` a result except also print out details like:
 ///
@@ -43,7 +44,13 @@ pub use t;
 /// Given an executable called `name`, return the filename for the
 /// executable for a particular target.
 pub fn exe(name: &str, target: TargetSelection) -> String {
-    if target.contains("windows") { format!("{}.exe", name) } else { name.to_string() }
+    if target.contains("windows") {
+        format!("{}.exe", name)
+    } else if target.contains("uefi") {
+        format!("{}.efi", name)
+    } else {
+        name.to_string()
+    }
 }
 
 /// Returns `true` if the file name given looks like a dynamic library.
@@ -104,7 +111,7 @@ pub struct TimeIt(bool, Instant);
 
 /// Returns an RAII structure that prints out how long it took to drop.
 pub fn timeit(builder: &Builder<'_>) -> TimeIt {
-    TimeIt(builder.config.dry_run, Instant::now())
+    TimeIt(builder.config.dry_run(), Instant::now())
 }
 
 impl Drop for TimeIt {
@@ -127,7 +134,7 @@ pub(crate) fn program_out_of_date(stamp: &Path, key: &str) -> bool {
 /// Symlinks two directories, using junctions on Windows and normal symlinks on
 /// Unix.
 pub fn symlink_dir(config: &Config, src: &Path, dest: &Path) -> io::Result<()> {
-    if config.dry_run {
+    if config.dry_run() {
         return Ok(());
     }
     let _ = fs::remove_dir(dest);
@@ -607,3 +614,16 @@ pub fn get_clang_cl_resource_dir(clang_cl_path: &str) -> PathBuf {
     let clang_rt_dir = clang_rt_builtins.parent().expect("The clang lib folder should exist");
     clang_rt_dir.to_path_buf()
 }
+
+pub fn lld_flag_no_threads(is_windows: bool) -> &'static str {
+    static LLD_NO_THREADS: OnceCell<(&'static str, &'static str)> = OnceCell::new();
+    let (windows, other) = LLD_NO_THREADS.get_or_init(|| {
+        let out = output(Command::new("lld").arg("-flavor").arg("ld").arg("--version"));
+        let newer = match (out.find(char::is_numeric), out.find('.')) {
+            (Some(b), Some(e)) => out.as_str()[b..e].parse::<i32>().ok().unwrap_or(14) > 10,
+            _ => true,
+        };
+        if newer { ("/threads:1", "--threads=1") } else { ("/no-threads", "--no-threads") }
+    });
+    if is_windows { windows } else { other }
+}
diff --git a/src/ci/docker/host-x86_64/disabled/dist-x86_64-haiku/Dockerfile b/src/ci/docker/host-x86_64/disabled/dist-x86_64-haiku/Dockerfile
index 637b5fa22f97..5ddd3f180396 100644
--- a/src/ci/docker/host-x86_64/disabled/dist-x86_64-haiku/Dockerfile
+++ b/src/ci/docker/host-x86_64/disabled/dist-x86_64-haiku/Dockerfile
@@ -47,6 +47,4 @@ ENV RUST_CONFIGURE_ARGS --disable-jemalloc \
   --set=$TARGET.cc=x86_64-unknown-haiku-gcc \
   --set=$TARGET.cxx=x86_64-unknown-haiku-g++ \
   --set=$TARGET.llvm-config=/bin/llvm-config-haiku
-ENV EXTERNAL_LLVM 1
-
 ENV SCRIPT python3 ../x.py dist --host=$HOST --target=$HOST
diff --git a/src/ci/docker/host-x86_64/dist-s390x-linux/Dockerfile b/src/ci/docker/host-x86_64/dist-s390x-linux/Dockerfile
index 7d77fdd30d1d..43a449b3a192 100644
--- a/src/ci/docker/host-x86_64/dist-s390x-linux/Dockerfile
+++ b/src/ci/docker/host-x86_64/dist-s390x-linux/Dockerfile
@@ -28,5 +28,5 @@ ENV \
 
 ENV HOSTS=s390x-unknown-linux-gnu
 
-ENV RUST_CONFIGURE_ARGS --enable-extended --enable-lld --disable-docs
+ENV RUST_CONFIGURE_ARGS --enable-extended --enable-lld --enable-profiler --disable-docs
 ENV SCRIPT python3 ../x.py dist --host $HOSTS --target $HOSTS
diff --git a/src/ci/docker/host-x86_64/dist-various-2/Dockerfile b/src/ci/docker/host-x86_64/dist-various-2/Dockerfile
index 8250ec0c3119..e1adabaac9b5 100644
--- a/src/ci/docker/host-x86_64/dist-various-2/Dockerfile
+++ b/src/ci/docker/host-x86_64/dist-various-2/Dockerfile
@@ -118,6 +118,9 @@ ENV TARGETS=$TARGETS,armv7-unknown-linux-gnueabi
 ENV TARGETS=$TARGETS,armv7-unknown-linux-musleabi
 ENV TARGETS=$TARGETS,i686-unknown-freebsd
 ENV TARGETS=$TARGETS,x86_64-unknown-none
+ENV TARGETS=$TARGETS,aarch64-unknown-uefi
+ENV TARGETS=$TARGETS,i686-unknown-uefi
+ENV TARGETS=$TARGETS,x86_64-unknown-uefi
 
 # As per https://bugs.launchpad.net/ubuntu/+source/gcc-defaults/+bug/1300211
 # we need asm in the search path for gcc-8 (for gnux32) but not in the search path of the
@@ -129,6 +132,4 @@ ENV RUST_CONFIGURE_ARGS --enable-extended --enable-lld --disable-docs \
   --set target.wasm32-wasi.wasi-root=/wasm32-wasi \
   --musl-root-armv7=/musl-armv7
 
-ENV EXTERNAL_LLVM 1
-
 ENV SCRIPT python3 ../x.py dist --host='' --target $TARGETS
diff --git a/src/ci/docker/host-x86_64/dist-x86_64-netbsd/Dockerfile b/src/ci/docker/host-x86_64/dist-x86_64-netbsd/Dockerfile
index fed4be4c30a7..d03c364547e0 100644
--- a/src/ci/docker/host-x86_64/dist-x86_64-netbsd/Dockerfile
+++ b/src/ci/docker/host-x86_64/dist-x86_64-netbsd/Dockerfile
@@ -1,7 +1,8 @@
-FROM ubuntu:16.04
+FROM ubuntu:20.04
 
 COPY scripts/cross-apt-packages.sh /scripts/
 RUN sh /scripts/cross-apt-packages.sh
+RUN DEBIAN_FRONTEND=noninteractive apt-get install -y zlib1g-dev
 
 COPY host-x86_64/dist-x86_64-netbsd/build-netbsd-toolchain.sh /tmp/
 RUN /tmp/build-netbsd-toolchain.sh
@@ -9,9 +10,6 @@ RUN /tmp/build-netbsd-toolchain.sh
 COPY scripts/sccache.sh /scripts/
 RUN sh /scripts/sccache.sh
 
-COPY scripts/cmake.sh /scripts/
-RUN /scripts/cmake.sh
-
 ENV PATH=$PATH:/x-tools/x86_64-unknown-netbsd/bin
 
 ENV \
@@ -21,6 +19,5 @@ ENV \
 
 ENV HOSTS=x86_64-unknown-netbsd
 
-ENV RUST_CONFIGURE_ARGS --enable-extended --disable-docs \
-    --set llvm.allow-old-toolchain
+ENV RUST_CONFIGURE_ARGS --enable-extended --disable-docs
 ENV SCRIPT python3 ../x.py dist --host $HOSTS --target $HOSTS
diff --git a/src/ci/docker/host-x86_64/dist-x86_64-netbsd/build-netbsd-toolchain.sh b/src/ci/docker/host-x86_64/dist-x86_64-netbsd/build-netbsd-toolchain.sh
index 5dfa47b4eed7..e0c008b76fa8 100755
--- a/src/ci/docker/host-x86_64/dist-x86_64-netbsd/build-netbsd-toolchain.sh
+++ b/src/ci/docker/host-x86_64/dist-x86_64-netbsd/build-netbsd-toolchain.sh
@@ -25,19 +25,19 @@ cd netbsd
 
 mkdir -p /x-tools/x86_64-unknown-netbsd/sysroot
 
-URL=https://ci-mirrors.rust-lang.org/rustc
+# URL=https://ci-mirrors.rust-lang.org/rustc
 
-# Originally from ftp://ftp.netbsd.org/pub/NetBSD/NetBSD-$BSD/source/sets/*.tgz
-curl $URL/2018-03-01-netbsd-src.tgz | tar xzf -
-curl $URL/2018-03-01-netbsd-gnusrc.tgz | tar xzf -
-curl $URL/2018-03-01-netbsd-sharesrc.tgz | tar xzf -
-curl $URL/2018-03-01-netbsd-syssrc.tgz | tar xzf -
+SOURCE_URL=https://cdn.netbsd.org/pub/NetBSD/NetBSD-9.0/source/sets
+curl $SOURCE_URL/src.tgz | tar xzf -
+curl $SOURCE_URL/gnusrc.tgz | tar xzf -
+curl $SOURCE_URL/sharesrc.tgz | tar xzf -
+curl $SOURCE_URL/syssrc.tgz | tar xzf -
 
-# Originally from ftp://ftp.netbsd.org/pub/NetBSD/NetBSD-$BSD/amd64/binary/sets/*.tgz
-curl $URL/2018-03-01-netbsd-base.tgz | \
-  tar xzf - -C /x-tools/x86_64-unknown-netbsd/sysroot ./usr/include ./usr/lib ./lib
-curl $URL/2018-03-01-netbsd-comp.tgz | \
-  tar xzf - -C /x-tools/x86_64-unknown-netbsd/sysroot ./usr/include ./usr/lib
+BINARY_URL=https://cdn.netbsd.org/pub/NetBSD/NetBSD-9.0/amd64/binary/sets
+curl $BINARY_URL/base.tar.xz | \
+  tar xJf - -C /x-tools/x86_64-unknown-netbsd/sysroot ./usr/include ./usr/lib ./lib
+curl $BINARY_URL/comp.tar.xz | \
+  tar xJf - -C /x-tools/x86_64-unknown-netbsd/sysroot ./usr/include ./usr/lib
 
 cd usr/src
 
diff --git a/src/ci/docker/host-x86_64/test-various/Dockerfile b/src/ci/docker/host-x86_64/test-various/Dockerfile
index b75e2f085cd3..b0f35bcb9ccf 100644
--- a/src/ci/docker/host-x86_64/test-various/Dockerfile
+++ b/src/ci/docker/host-x86_64/test-various/Dockerfile
@@ -16,7 +16,9 @@ RUN apt-get update && DEBIAN_FRONTEND=noninteractive apt-get install -y --no-ins
   pkg-config \
   xz-utils \
   wget \
-  patch
+  patch \
+  ovmf \
+  qemu-system-x86
 
 RUN curl -sL https://nodejs.org/dist/v15.14.0/node-v15.14.0-linux-x64.tar.xz | \
   tar -xJ
@@ -64,4 +66,9 @@ ENV MUSL_TARGETS=x86_64-unknown-linux-musl \
     CXX_x86_64_unknown_linux_musl=x86_64-linux-musl-g++
 ENV MUSL_SCRIPT python3 /checkout/x.py --stage 2 test --host='' --target $MUSL_TARGETS
 
-ENV SCRIPT $WASM_SCRIPT && $NVPTX_SCRIPT && $MUSL_SCRIPT
+COPY host-x86_64/test-various/uefi_qemu_test /uefi_qemu_test
+ENV UEFI_TARGETS=x86_64-unknown-uefi
+ENV UEFI_SCRIPT python3 /checkout/x.py --stage 2 build --host='' --target $UEFI_TARGETS && \
+  python3 -u /uefi_qemu_test/run.py
+
+ENV SCRIPT $WASM_SCRIPT && $NVPTX_SCRIPT && $MUSL_SCRIPT && $UEFI_SCRIPT
diff --git a/src/ci/docker/host-x86_64/test-various/uefi_qemu_test/Cargo.toml b/src/ci/docker/host-x86_64/test-various/uefi_qemu_test/Cargo.toml
new file mode 100644
index 000000000000..fa8e5b3d0806
--- /dev/null
+++ b/src/ci/docker/host-x86_64/test-various/uefi_qemu_test/Cargo.toml
@@ -0,0 +1,9 @@
+[package]
+name = "uefi_qemu_test"
+version = "0.0.0"
+edition = "2021"
+
+[workspace]
+
+[dependencies]
+r-efi = "4.1.0"
diff --git a/src/ci/docker/host-x86_64/test-various/uefi_qemu_test/run.py b/src/ci/docker/host-x86_64/test-various/uefi_qemu_test/run.py
new file mode 100644
index 000000000000..46793ce3afa1
--- /dev/null
+++ b/src/ci/docker/host-x86_64/test-various/uefi_qemu_test/run.py
@@ -0,0 +1,96 @@
+#!/usr/bin/env python3
+
+import os
+import shutil
+import subprocess
+import sys
+import tempfile
+
+from pathlib import Path
+
+
+def run(*cmd, capture=False, check=True, env=None):
+    """Print and run a command, optionally capturing the output."""
+    cmd = [str(p) for p in cmd]
+    print(' '.join(cmd))
+    return subprocess.run(cmd,
+                          capture_output=capture,
+                          check=check,
+                          env=env,
+                          text=True)
+
+
+def build_and_run(tmp_dir):
+    host_artifacts = Path('/checkout/obj/build/x86_64-unknown-linux-gnu')
+    stage0 = host_artifacts / 'stage0/bin'
+    stage2 = host_artifacts / 'stage2/bin'
+
+    env = dict(os.environ)
+    env['PATH'] = '{}:{}:{}'.format(stage2, stage0, env['PATH'])
+
+    # Copy the test create into `tmp_dir`.
+    test_crate = Path(tmp_dir) / 'uefi_qemu_test'
+    shutil.copytree('/uefi_qemu_test', test_crate)
+
+    # Build the UEFI executable.
+    target = 'x86_64-unknown-uefi'
+    run('cargo',
+        'build',
+        '--manifest-path',
+        test_crate / 'Cargo.toml',
+        '--target',
+        target,
+        env=env)
+
+    # Create a mock EFI System Partition in a subdirectory.
+    esp = test_crate / 'esp'
+    boot = esp / 'efi/boot'
+    os.makedirs(boot, exist_ok=True)
+
+    # Copy the executable into the ESP.
+    src_exe_path = test_crate / 'target' / target / 'debug/uefi_qemu_test.efi'
+    shutil.copy(src_exe_path, boot / 'bootx64.efi')
+
+    # Run the executable in QEMU and capture the output.
+    qemu = 'qemu-system-x86_64'
+    ovmf_dir = Path('/usr/share/OVMF')
+    ovmf_code = ovmf_dir / 'OVMF_CODE.fd'
+    ovmf_vars = ovmf_dir / 'OVMF_VARS.fd'
+    output = run(qemu,
+                 '-display',
+                 'none',
+                 '-serial',
+                 'stdio',
+                 '-drive',
+                 f'if=pflash,format=raw,readonly=on,file={ovmf_code}',
+                 '-drive',
+                 f'if=pflash,format=raw,readonly=on,file={ovmf_vars}',
+                 '-drive',
+                 f'format=raw,file=fat:rw:{esp}',
+                 capture=True,
+                 # Ubuntu 20.04 (which is what the Dockerfile currently
+                 # uses) provides QEMU 4.2.1, which segfaults on
+                 # shutdown under some circumstances. That has been
+                 # fixed in newer versions of QEMU, but for now just
+                 # don't check the exit status.
+                 check=False).stdout
+
+    if 'Hello World!' in output:
+        print('VM produced expected output')
+    else:
+        print('unexpected VM output:')
+        print('---start---')
+        print(output)
+        print('---end---')
+        sys.exit(1)
+
+
+def main():
+    # Create a temporary directory so that we have a writeable
+    # workspace.
+    with tempfile.TemporaryDirectory() as tmp_dir:
+        build_and_run(tmp_dir)
+
+
+if __name__ == "__main__":
+    main()
diff --git a/src/ci/docker/host-x86_64/test-various/uefi_qemu_test/src/main.rs b/src/ci/docker/host-x86_64/test-various/uefi_qemu_test/src/main.rs
new file mode 100644
index 000000000000..2ec554c140b5
--- /dev/null
+++ b/src/ci/docker/host-x86_64/test-various/uefi_qemu_test/src/main.rs
@@ -0,0 +1,45 @@
+// Code is adapted from this hello world example:
+// https://doc.rust-lang.org/nightly/rustc/platform-support/unknown-uefi.html
+
+#![no_main]
+#![no_std]
+
+use core::{panic, ptr};
+use r_efi::efi::{Char16, Handle, Status, SystemTable, RESET_SHUTDOWN};
+
+#[panic_handler]
+fn panic_handler(_info: &panic::PanicInfo) -> ! {
+    loop {}
+}
+
+#[export_name = "efi_main"]
+pub extern "C" fn main(_h: Handle, st: *mut SystemTable) -> Status {
+    let s = [
+        0x0048u16, 0x0065u16, 0x006cu16, 0x006cu16, 0x006fu16, // "Hello"
+        0x0020u16, //                                             " "
+        0x0057u16, 0x006fu16, 0x0072u16, 0x006cu16, 0x0064u16, // "World"
+        0x0021u16, //                                             "!"
+        0x000au16, //                                             "\n"
+        0x0000u16, //                                             NUL
+    ];
+
+    // Print "Hello World!".
+    let r = unsafe { ((*(*st).con_out).output_string)((*st).con_out, s.as_ptr() as *mut Char16) };
+    if r.is_error() {
+        return r;
+    }
+
+    // Shut down.
+    unsafe {
+        ((*((*st).runtime_services)).reset_system)(
+            RESET_SHUTDOWN,
+            Status::SUCCESS,
+            0,
+            ptr::null_mut(),
+        );
+    }
+
+    // This should never be reached because `reset_system` should never
+    // return, so fail with an error if we get here.
+    Status::UNSUPPORTED
+}
diff --git a/src/ci/docker/host-x86_64/x86_64-gnu-llvm-13-stage1/Dockerfile b/src/ci/docker/host-x86_64/x86_64-gnu-llvm-13-stage1/Dockerfile
index 1289f116fe9f..23f2215c2d93 100644
--- a/src/ci/docker/host-x86_64/x86_64-gnu-llvm-13-stage1/Dockerfile
+++ b/src/ci/docker/host-x86_64/x86_64-gnu-llvm-13-stage1/Dockerfile
@@ -29,7 +29,6 @@ RUN sh /scripts/sccache.sh
 # We are disabling CI LLVM since this builder is intentionally using a host
 # LLVM, rather than the typical src/llvm-project LLVM.
 ENV NO_DOWNLOAD_CI_LLVM 1
-ENV EXTERNAL_LLVM 1
 
 # Using llvm-link-shared due to libffi issues -- see #34486
 ENV RUST_CONFIGURE_ARGS \
diff --git a/src/ci/docker/host-x86_64/x86_64-gnu-llvm-13/Dockerfile b/src/ci/docker/host-x86_64/x86_64-gnu-llvm-13/Dockerfile
index 4b89a72baa1c..8f6831bc54e6 100644
--- a/src/ci/docker/host-x86_64/x86_64-gnu-llvm-13/Dockerfile
+++ b/src/ci/docker/host-x86_64/x86_64-gnu-llvm-13/Dockerfile
@@ -40,7 +40,6 @@ RUN sh /scripts/sccache.sh
 # We are disabling CI LLVM since this builder is intentionally using a host
 # LLVM, rather than the typical src/llvm-project LLVM.
 ENV NO_DOWNLOAD_CI_LLVM 1
-ENV EXTERNAL_LLVM 1
 
 # Using llvm-link-shared due to libffi issues -- see #34486
 ENV RUST_CONFIGURE_ARGS \
diff --git a/src/ci/docker/host-x86_64/x86_64-gnu-tools/browser-ui-test.version b/src/ci/docker/host-x86_64/x86_64-gnu-tools/browser-ui-test.version
index cc96715b2857..ed0d9e9902b9 100644
--- a/src/ci/docker/host-x86_64/x86_64-gnu-tools/browser-ui-test.version
+++ b/src/ci/docker/host-x86_64/x86_64-gnu-tools/browser-ui-test.version
@@ -1 +1 @@
-0.12.7
\ No newline at end of file
+0.13.1
\ No newline at end of file
diff --git a/src/ci/docker/host-x86_64/x86_64-gnu-tools/checktools.sh b/src/ci/docker/host-x86_64/x86_64-gnu-tools/checktools.sh
index 3e1f39eaab5a..7dde6370904b 100755
--- a/src/ci/docker/host-x86_64/x86_64-gnu-tools/checktools.sh
+++ b/src/ci/docker/host-x86_64/x86_64-gnu-tools/checktools.sh
@@ -25,3 +25,9 @@ python3 "$X_PY" test --stage 2 check-tools
 python3 "$X_PY" test --stage 2 src/tools/clippy
 python3 "$X_PY" test --stage 2 src/tools/rustfmt
 python3 "$X_PY" test --stage 2 src/tools/miri
+# We natively run this script on x86_64-unknown-linux-gnu and x86_64-pc-windows-msvc.
+# Also cover some other targets (on both of these hosts) via cross-testing.
+export BOOTSTRAP_SKIP_TARGET_SANITY=1 # we don't need `cc` for these targets
+python3 "$X_PY" test --stage 2 src/tools/miri --target i686-pc-windows-msvc
+python3 "$X_PY" test --stage 2 src/tools/miri --target aarch64-apple-darwin
+unset BOOTSTRAP_SKIP_TARGET_SANITY
diff --git a/src/ci/docker/scripts/fuchsia-test-runner.py b/src/ci/docker/scripts/fuchsia-test-runner.py
new file mode 100644
index 000000000000..a2708d16947f
--- /dev/null
+++ b/src/ci/docker/scripts/fuchsia-test-runner.py
@@ -0,0 +1,1041 @@
+#!/usr/bin/env python3
+
+"""
+The Rust toolchain test runner for Fuchsia.
+
+For instructions on running the compiler test suite, see
+https://doc.rust-lang.org/stable/rustc/platform-support/fuchsia.html#aarch64-fuchsia-and-x86_64-fuchsia
+"""
+
+import argparse
+from dataclasses import dataclass
+import glob
+import hashlib
+import json
+import os
+import platform
+import re
+import shutil
+import signal
+import subprocess
+import sys
+from typing import ClassVar, List
+
+
+@dataclass
+class TestEnvironment:
+    rust_dir: str
+    sdk_dir: str
+    target_arch: str
+    package_server_pid: int = None
+    emu_addr: str = None
+    libstd_name: str = None
+    libtest_name: str = None
+    verbose: bool = False
+
+    @staticmethod
+    def tmp_dir():
+        tmp_dir = os.environ.get("TEST_TOOLCHAIN_TMP_DIR")
+        if tmp_dir is not None:
+            return os.path.abspath(tmp_dir)
+        return os.path.join(os.path.dirname(__file__), "tmp~")
+
+    @classmethod
+    def env_file_path(cls):
+        return os.path.join(cls.tmp_dir(), "test_env.json")
+
+    @classmethod
+    def from_args(cls, args):
+        return cls(
+            os.path.abspath(args.rust),
+            os.path.abspath(args.sdk),
+            args.target_arch,
+            verbose=args.verbose,
+        )
+
+    @classmethod
+    def read_from_file(cls):
+        with open(cls.env_file_path(), encoding="utf-8") as f:
+            test_env = json.loads(f.read())
+            return cls(
+                test_env["rust_dir"],
+                test_env["sdk_dir"],
+                test_env["target_arch"],
+                libstd_name=test_env["libstd_name"],
+                libtest_name=test_env["libtest_name"],
+                emu_addr=test_env["emu_addr"],
+                package_server_pid=test_env["package_server_pid"],
+                verbose=test_env["verbose"],
+            )
+
+    def image_name(self):
+        if self.target_arch == "x64":
+            return "qemu-x64"
+        if self.target_arch == "arm64":
+            return "qemu-arm64"
+        raise Exception(f"Unrecognized target architecture {self.target_arch}")
+
+    def write_to_file(self):
+        with open(self.env_file_path(), "w", encoding="utf-8") as f:
+            f.write(json.dumps(self.__dict__))
+
+    def ssh_dir(self):
+        return os.path.join(self.tmp_dir(), "ssh")
+
+    def ssh_keyfile_path(self):
+        return os.path.join(self.ssh_dir(), "fuchsia_ed25519")
+
+    def ssh_authfile_path(self):
+        return os.path.join(self.ssh_dir(), "fuchsia_authorized_keys")
+
+    def vdl_output_path(self):
+        return os.path.join(self.tmp_dir(), "vdl_output")
+
+    def package_server_log_path(self):
+        return os.path.join(self.tmp_dir(), "package_server_log")
+
+    def emulator_log_path(self):
+        return os.path.join(self.tmp_dir(), "emulator_log")
+
+    def packages_dir(self):
+        return os.path.join(self.tmp_dir(), "packages")
+
+    def output_dir(self):
+        return os.path.join(self.tmp_dir(), "output")
+
+    TEST_REPO_NAME: ClassVar[str] = "rust-testing"
+
+    def repo_dir(self):
+        return os.path.join(self.tmp_dir(), self.TEST_REPO_NAME)
+
+    def rustlib_dir(self):
+        if self.target_arch == "x64":
+            return "x86_64-fuchsia"
+        if self.target_arch == "arm64":
+            return "aarch64-fuchsia"
+        raise Exception(f"Unrecognized target architecture {self.target_arch}")
+
+    def libs_dir(self):
+        return os.path.join(
+            self.rust_dir,
+            "lib",
+        )
+
+    def rustlibs_dir(self):
+        return os.path.join(
+            self.libs_dir(),
+            "rustlib",
+            self.rustlib_dir(),
+            "lib",
+        )
+
+    def sdk_arch(self):
+        machine = platform.machine()
+        if machine == "x86_64":
+            return "x64"
+        if machine == "arm":
+            return "a64"
+        raise Exception(f"Unrecognized host architecture {machine}")
+
+    def tool_path(self, tool):
+        return os.path.join(self.sdk_dir, "tools", self.sdk_arch(), tool)
+
+    def host_arch_triple(self):
+        machine = platform.machine()
+        if machine == "x86_64":
+            return "x86_64-unknown-linux-gnu"
+        if machine == "arm":
+            return "aarch64-unknown-linux-gnu"
+        raise Exception(f"Unrecognized host architecture {machine}")
+
+    def zxdb_script_path(self):
+        return os.path.join(self.tmp_dir(), "zxdb_script")
+
+    def log_info(self, msg):
+        print(msg)
+
+    def log_debug(self, msg):
+        if self.verbose:
+            print(msg)
+
+    def subprocess_output(self):
+        if self.verbose:
+            return sys.stdout
+        return subprocess.DEVNULL
+
+    def ffx_daemon_log_path(self):
+        return os.path.join(self.tmp_dir(), "ffx_daemon_log")
+
+    def ffx_isolate_dir(self):
+        return os.path.join(self.tmp_dir(), "ffx_isolate")
+
+    def ffx_home_dir(self):
+        return os.path.join(self.ffx_isolate_dir(), "user-home")
+
+    def ffx_tmp_dir(self):
+        return os.path.join(self.ffx_isolate_dir(), "tmp")
+
+    def ffx_log_dir(self):
+        return os.path.join(self.ffx_isolate_dir(), "log")
+
+    def ffx_user_config_dir(self):
+        return os.path.join(self.ffx_xdg_config_home(), "Fuchsia", "ffx", "config")
+
+    def ffx_user_config_path(self):
+        return os.path.join(self.ffx_user_config_dir(), "config.json")
+
+    def ffx_xdg_config_home(self):
+        if platform.system() == "Darwin":
+            return os.path.join(self.ffx_home_dir(), "Library", "Preferences")
+        return os.path.join(self.ffx_home_dir(), ".local", "share")
+
+    def ffx_ascendd_path(self):
+        return os.path.join(self.ffx_tmp_dir(), "ascendd")
+
+    def start_ffx_isolation(self):
+        # Most of this is translated directly from ffx's isolate library
+        os.mkdir(self.ffx_isolate_dir())
+        os.mkdir(self.ffx_home_dir())
+        os.mkdir(self.ffx_tmp_dir())
+        os.mkdir(self.ffx_log_dir())
+
+        fuchsia_dir = os.path.join(self.ffx_home_dir(), ".fuchsia")
+        os.mkdir(fuchsia_dir)
+
+        fuchsia_debug_dir = os.path.join(fuchsia_dir, "debug")
+        os.mkdir(fuchsia_debug_dir)
+
+        metrics_dir = os.path.join(fuchsia_dir, "metrics")
+        os.mkdir(metrics_dir)
+
+        analytics_path = os.path.join(metrics_dir, "analytics-status")
+        with open(analytics_path, "w", encoding="utf-8") as analytics_file:
+            print("0", file=analytics_file)
+
+        ffx_path = os.path.join(metrics_dir, "ffx")
+        with open(ffx_path, "w", encoding="utf-8") as ffx_file:
+            print("1", file=ffx_file)
+
+        os.makedirs(self.ffx_user_config_dir())
+
+        with open(
+            self.ffx_user_config_path(), "w", encoding="utf-8"
+        ) as config_json_file:
+            user_config_for_test = {
+                "log": {
+                    "enabled": True,
+                    "dir": self.ffx_log_dir(),
+                },
+                "overnet": {
+                    "socket": self.ffx_ascendd_path(),
+                },
+                "ssh": {
+                    "pub": self.ssh_authfile_path(),
+                    "priv": self.ssh_keyfile_path(),
+                },
+                "test": {
+                    "is_isolated": True,
+                    "experimental_structured_output": True,
+                },
+            }
+            print(json.dumps(user_config_for_test), file=config_json_file)
+
+        ffx_env_path = os.path.join(self.ffx_user_config_dir(), ".ffx_env")
+        with open(ffx_env_path, "w", encoding="utf-8") as ffx_env_file:
+            ffx_env_config_for_test = {
+                "user": self.ffx_user_config_path(),
+                "build": None,
+                "global": None,
+            }
+            print(json.dumps(ffx_env_config_for_test), file=ffx_env_file)
+
+        # Start ffx daemon
+        # We want this to be a long-running process that persists after the script finishes
+        # pylint: disable=consider-using-with
+        with open(
+            self.ffx_daemon_log_path(), "w", encoding="utf-8"
+        ) as ffx_daemon_log_file:
+            subprocess.Popen(
+                [
+                    self.tool_path("ffx"),
+                    "--config",
+                    self.ffx_user_config_path(),
+                    "daemon",
+                    "start",
+                ],
+                env=self.ffx_cmd_env(),
+                stdout=ffx_daemon_log_file,
+                stderr=ffx_daemon_log_file,
+            )
+
+    def ffx_cmd_env(self):
+        result = {
+            "HOME": self.ffx_home_dir(),
+            "XDG_CONFIG_HOME": self.ffx_xdg_config_home(),
+            "ASCENDD": self.ffx_ascendd_path(),
+            "FUCHSIA_SSH_KEY": self.ssh_keyfile_path(),
+            # We want to use our own specified temp directory
+            "TMP": self.tmp_dir(),
+            "TEMP": self.tmp_dir(),
+            "TMPDIR": self.tmp_dir(),
+            "TEMPDIR": self.tmp_dir(),
+        }
+
+        return result
+
+    def stop_ffx_isolation(self):
+        subprocess.check_call(
+            [
+                self.tool_path("ffx"),
+                "--config",
+                self.ffx_user_config_path(),
+                "daemon",
+                "stop",
+            ],
+            env=self.ffx_cmd_env(),
+            stdout=self.subprocess_output(),
+            stderr=self.subprocess_output(),
+        )
+
+    def start(self):
+        """Sets up the testing environment and prepares to run tests.
+
+        Args:
+            args: The command-line arguments to this command.
+
+        During setup, this function will:
+        - Locate necessary shared libraries
+        - Create a new temp directory (this is where all temporary files are stored)
+        - Start an emulator
+        - Start an update server
+        - Create a new package repo and register it with the emulator
+        - Write test environment settings to a temporary file
+        """
+
+        # Initialize temp directory
+        if not os.path.exists(self.tmp_dir()):
+            os.mkdir(self.tmp_dir())
+        elif len(os.listdir(self.tmp_dir())) != 0:
+            raise Exception(f"Temp directory is not clean (in {self.tmp_dir()})")
+
+        os.mkdir(self.ssh_dir())
+        os.mkdir(self.output_dir())
+
+        # Find libstd and libtest
+        libstd_paths = glob.glob(os.path.join(self.rustlibs_dir(), "libstd-*.so"))
+        libtest_paths = glob.glob(os.path.join(self.rustlibs_dir(), "libtest-*.so"))
+
+        if not libstd_paths:
+            raise Exception(f"Failed to locate libstd (in {self.rustlibs_dir()})")
+
+        if not libtest_paths:
+            raise Exception(f"Failed to locate libtest (in {self.rustlibs_dir()})")
+
+        self.libstd_name = os.path.basename(libstd_paths[0])
+        self.libtest_name = os.path.basename(libtest_paths[0])
+
+        # Generate SSH keys for the emulator to use
+        self.log_info("Generating SSH keys...")
+        subprocess.check_call(
+            [
+                "ssh-keygen",
+                "-N",
+                "",
+                "-t",
+                "ed25519",
+                "-f",
+                self.ssh_keyfile_path(),
+                "-C",
+                "Generated by test_toolchain.py",
+            ],
+            stdout=self.subprocess_output(),
+            stderr=self.subprocess_output(),
+        )
+        authfile_contents = subprocess.check_output(
+            [
+                "ssh-keygen",
+                "-y",
+                "-f",
+                self.ssh_keyfile_path(),
+            ],
+            stderr=self.subprocess_output(),
+        )
+        with open(self.ssh_authfile_path(), "wb") as authfile:
+            authfile.write(authfile_contents)
+
+        # Start ffx isolation
+        self.log_info("Starting ffx isolation...")
+        self.start_ffx_isolation()
+
+        # Start emulator (this will generate the vdl output)
+        self.log_info("Starting emulator...")
+        subprocess.check_call(
+            [
+                self.tool_path("fvdl"),
+                "--sdk",
+                "start",
+                "--tuntap",
+                "--headless",
+                "--nointeractive",
+                "--ssh",
+                self.ssh_dir(),
+                "--vdl-output",
+                self.vdl_output_path(),
+                "--emulator-log",
+                self.emulator_log_path(),
+                "--image-name",
+                self.image_name(),
+            ],
+            stdout=self.subprocess_output(),
+            stderr=self.subprocess_output(),
+        )
+
+        # Parse vdl output for relevant information
+        with open(self.vdl_output_path(), encoding="utf-8") as f:
+            vdl_content = f.read()
+            matches = re.search(
+                r'network_address:\s+"\[([0-9a-f]{1,4}:(:[0-9a-f]{1,4}){4}%qemu)\]"',
+                vdl_content,
+            )
+            self.emu_addr = matches.group(1)
+
+        # Create new package repo
+        self.log_info("Creating package repo...")
+        subprocess.check_call(
+            [
+                self.tool_path("pm"),
+                "newrepo",
+                "-repo",
+                self.repo_dir(),
+            ],
+            stdout=self.subprocess_output(),
+            stderr=self.subprocess_output(),
+        )
+
+        # Start package server
+        self.log_info("Starting package server...")
+        with open(
+            self.package_server_log_path(), "w", encoding="utf-8"
+        ) as package_server_log:
+            # We want this to be a long-running process that persists after the script finishes
+            # pylint: disable=consider-using-with
+            self.package_server_pid = subprocess.Popen(
+                [
+                    self.tool_path("pm"),
+                    "serve",
+                    "-vt",
+                    "-repo",
+                    self.repo_dir(),
+                    "-l",
+                    ":8084",
+                ],
+                stdout=package_server_log,
+                stderr=package_server_log,
+            ).pid
+
+        # Register package server with emulator
+        self.log_info("Registering package server...")
+        ssh_client = subprocess.check_output(
+            [
+                "ssh",
+                "-i",
+                self.ssh_keyfile_path(),
+                "-o",
+                "StrictHostKeyChecking=accept-new",
+                self.emu_addr,
+                "-f",
+                "echo $SSH_CLIENT",
+            ],
+            text=True,
+        )
+        repo_addr = ssh_client.split()[0].replace("%", "%25")
+        repo_url = f"http://[{repo_addr}]:8084/config.json"
+        subprocess.check_call(
+            [
+                "ssh",
+                "-i",
+                self.ssh_keyfile_path(),
+                "-o",
+                "StrictHostKeyChecking=accept-new",
+                self.emu_addr,
+                "-f",
+                f"pkgctl repo add url -f 1 -n {self.TEST_REPO_NAME} {repo_url}",
+            ],
+            stdout=self.subprocess_output(),
+            stderr=self.subprocess_output(),
+        )
+
+        # Write to file
+        self.write_to_file()
+
+        self.log_info("Success! Your environment is ready to run tests.")
+
+    # FIXME: shardify this
+    # `facet` statement required for TCP testing via
+    # protocol `fuchsia.posix.socket.Provider`. See
+    # https://fuchsia.dev/fuchsia-src/development/testing/components/test_runner_framework?hl=en#legacy_non-hermetic_tests
+    CML_TEMPLATE: ClassVar[
+        str
+    ] = """
+    {{
+        program: {{
+            runner: "elf_test_runner",
+            binary: "bin/{exe_name}",
+            forward_stderr_to: "log",
+            forward_stdout_to: "log",
+            environ: [{env_vars}
+            ]
+        }},
+        capabilities: [
+            {{ protocol: "fuchsia.test.Suite" }},
+        ],
+        expose: [
+            {{
+                protocol: "fuchsia.test.Suite",
+                from: "self",
+            }},
+        ],
+        use: [
+            {{ storage: "data", path: "/data" }},
+            {{ protocol: [ "fuchsia.process.Launcher" ] }},
+            {{ protocol: [ "fuchsia.posix.socket.Provider" ] }}
+        ],
+        facets: {{
+            "fuchsia.test": {{ type: "system" }},
+        }},
+    }}
+    """
+
+    MANIFEST_TEMPLATE = """
+    meta/package={package_dir}/meta/package
+    meta/{package_name}.cm={package_dir}/meta/{package_name}.cm
+    bin/{exe_name}={bin_path}
+    lib/{libstd_name}={rust_dir}/lib/rustlib/{rustlib_dir}/lib/{libstd_name}
+    lib/{libtest_name}={rust_dir}/lib/rustlib/{rustlib_dir}/lib/{libtest_name}
+    lib/ld.so.1={sdk_dir}/arch/{target_arch}/sysroot/lib/libc.so
+    lib/libzircon.so={sdk_dir}/arch/{target_arch}/sysroot/lib/libzircon.so
+    lib/libfdio.so={sdk_dir}/arch/{target_arch}/lib/libfdio.so
+    """
+
+    TEST_ENV_VARS: ClassVar[List[str]] = [
+        "TEST_EXEC_ENV",
+        "RUST_MIN_STACK",
+        "RUST_BACKTRACE",
+        "RUST_NEWRT",
+        "RUST_LOG",
+        "RUST_TEST_THREADS",
+    ]
+
+    def run(self, args):
+        """Runs the requested test in the testing environment.
+
+        Args:
+        args: The command-line arguments to this command.
+        Returns:
+        The return code of the test (0 for success, else failure).
+
+        To run a test, this function will:
+        - Create, compile, archive, and publish a test package
+        - Run the test package on the emulator
+        - Forward the test's stdout and stderr as this script's stdout and stderr
+        """
+
+        bin_path = os.path.abspath(args.bin_path)
+
+        # Build a unique, deterministic name for the test using the name of the
+        # binary and the last 6 hex digits of the hash of the full path
+        def path_checksum(path):
+            m = hashlib.sha256()
+            m.update(path.encode("utf-8"))
+            return m.hexdigest()[0:6]
+
+        base_name = os.path.basename(os.path.dirname(args.bin_path))
+        exe_name = base_name.lower().replace(".", "_")
+        package_name = f"{exe_name}_{path_checksum(bin_path)}"
+
+        package_dir = os.path.join(self.packages_dir(), package_name)
+        cml_path = os.path.join(package_dir, "meta", f"{package_name}.cml")
+        cm_path = os.path.join(package_dir, "meta", f"{package_name}.cm")
+        manifest_path = os.path.join(package_dir, f"{package_name}.manifest")
+        far_path = os.path.join(package_dir, f"{package_name}-0.far")
+
+        shared_libs = args.shared_libs[: args.n]
+        arguments = args.shared_libs[args.n :]
+
+        test_output_dir = os.path.join(self.output_dir(), package_name)
+
+        # Clean and create temporary output directory
+        if os.path.exists(test_output_dir):
+            shutil.rmtree(test_output_dir)
+
+        os.mkdir(test_output_dir)
+
+        # Open log file
+        log_path = os.path.join(test_output_dir, "log")
+        with open(log_path, "w", encoding="utf-8") as log_file:
+
+            def log(msg):
+                print(msg, file=log_file)
+                log_file.flush()
+
+            log(f"Bin path: {bin_path}")
+
+            log("Setting up package...")
+
+            # Set up package
+            subprocess.check_call(
+                [
+                    self.tool_path("pm"),
+                    "-o",
+                    package_dir,
+                    "-n",
+                    package_name,
+                    "init",
+                ],
+                stdout=log_file,
+                stderr=log_file,
+            )
+
+            log("Writing CML...")
+
+            # Write and compile CML
+            with open(cml_path, "w", encoding="utf-8") as cml:
+                # Collect environment variables
+                env_vars = ""
+                for var_name in self.TEST_ENV_VARS:
+                    var_value = os.getenv(var_name)
+                    if var_value is not None:
+                        env_vars += f'\n            "{var_name}={var_value}",'
+
+                # Default to no backtrace for test suite
+                if os.getenv("RUST_BACKTRACE") == None:
+                    env_vars += f'\n            "RUST_BACKTRACE=0",'
+
+                cml.write(
+                    self.CML_TEMPLATE.format(env_vars=env_vars, exe_name=exe_name)
+                )
+
+            log("Compiling CML...")
+
+            subprocess.check_call(
+                [
+                    self.tool_path("cmc"),
+                    "compile",
+                    cml_path,
+                    "--includepath",
+                    ".",
+                    "--output",
+                    cm_path,
+                ],
+                stdout=log_file,
+                stderr=log_file,
+            )
+
+            log("Writing manifest...")
+
+            # Write, build, and archive manifest
+            with open(manifest_path, "w", encoding="utf-8") as manifest:
+                manifest.write(
+                    self.MANIFEST_TEMPLATE.format(
+                        bin_path=bin_path,
+                        exe_name=exe_name,
+                        package_dir=package_dir,
+                        package_name=package_name,
+                        rust_dir=self.rust_dir,
+                        rustlib_dir=self.rustlib_dir(),
+                        sdk_dir=self.sdk_dir,
+                        libstd_name=self.libstd_name,
+                        libtest_name=self.libtest_name,
+                        target_arch=self.target_arch,
+                    )
+                )
+                for shared_lib in shared_libs:
+                    manifest.write(f"lib/{os.path.basename(shared_lib)}={shared_lib}\n")
+
+            log("Compiling and archiving manifest...")
+
+            subprocess.check_call(
+                [
+                    self.tool_path("pm"),
+                    "-o",
+                    package_dir,
+                    "-m",
+                    manifest_path,
+                    "build",
+                ],
+                stdout=log_file,
+                stderr=log_file,
+            )
+            subprocess.check_call(
+                [
+                    self.tool_path("pm"),
+                    "-o",
+                    package_dir,
+                    "-m",
+                    manifest_path,
+                    "archive",
+                ],
+                stdout=log_file,
+                stderr=log_file,
+            )
+
+            log("Publishing package to repo...")
+
+            # Publish package to repo
+            subprocess.check_call(
+                [
+                    self.tool_path("pm"),
+                    "publish",
+                    "-a",
+                    "-repo",
+                    self.repo_dir(),
+                    "-f",
+                    far_path,
+                ],
+                stdout=log_file,
+                stderr=log_file,
+            )
+
+            log("Running ffx test...")
+
+            # Run test on emulator
+            subprocess.run(
+                [
+                    self.tool_path("ffx"),
+                    "--config",
+                    self.ffx_user_config_path(),
+                    "test",
+                    "run",
+                    f"fuchsia-pkg://{self.TEST_REPO_NAME}/{package_name}#meta/{package_name}.cm",
+                    "--min-severity-logs",
+                    "TRACE",
+                    "--output-directory",
+                    test_output_dir,
+                    "--",
+                ]
+                + arguments,
+                env=self.ffx_cmd_env(),
+                check=False,
+                stdout=log_file,
+                stderr=log_file,
+            )
+
+            log("Reporting test suite output...")
+
+            # Read test suite output
+            run_summary_path = os.path.join(test_output_dir, "run_summary.json")
+            if os.path.exists(run_summary_path):
+                with open(run_summary_path, encoding="utf-8") as f:
+                    run_summary = json.loads(f.read())
+
+                suite = run_summary["data"]["suites"][0]
+                case = suite["cases"][0]
+
+                return_code = 0 if case["outcome"] == "PASSED" else 1
+
+                artifacts = case["artifacts"]
+                artifact_dir = case["artifact_dir"]
+                stdout_path = None
+                stderr_path = None
+
+                for path, artifact in artifacts.items():
+                    artifact_path = os.path.join(test_output_dir, artifact_dir, path)
+                    artifact_type = artifact["artifact_type"]
+
+                    if artifact_type == "STDERR":
+                        stderr_path = artifact_path
+                    elif artifact_type == "STDOUT":
+                        stdout_path = artifact_path
+
+                if stdout_path is not None and os.path.exists(stdout_path):
+                    with open(stdout_path, encoding="utf-8") as f:
+                        print(f.read(), file=sys.stdout, end="")
+
+                if stderr_path is not None and os.path.exists(stderr_path):
+                    with open(stderr_path, encoding="utf-8") as f:
+                        print(f.read(), file=sys.stderr, end="")
+            else:
+                log("Failed to open test run summary")
+                return_code = 254
+
+            log("Done!")
+
+        return return_code
+
+    def stop(self):
+        """Shuts down and cleans up the testing environment.
+
+        Args:
+        args: The command-line arguments to this command.
+        Returns:
+        The return code of the test (0 for success, else failure).
+
+        During cleanup, this function will stop the emulator, package server, and
+        update server, then delete all temporary files. If an error is encountered
+        while stopping any running processes, the temporary files will not be deleted.
+        Passing --delete-tmp will force the process to delete the files anyway.
+        """
+
+        self.log_debug("Reporting logs...")
+
+        # Print test log files
+        for test_dir in os.listdir(self.output_dir()):
+            log_path = os.path.join(self.output_dir(), test_dir, "log")
+            self.log_debug(f"\n---- Logs for test '{test_dir}' ----\n")
+            if os.path.exists(log_path):
+                with open(log_path, encoding="utf-8") as log:
+                    self.log_debug(log.read())
+            else:
+                self.log_debug("No logs found")
+
+        # Print the emulator log
+        self.log_debug("\n---- Emulator logs ----\n")
+        if os.path.exists(self.emulator_log_path()):
+            with open(self.emulator_log_path(), encoding="utf-8") as log:
+                self.log_debug(log.read())
+        else:
+            self.log_debug("No emulator logs found")
+
+        # Print the package server log
+        self.log_debug("\n---- Package server log ----\n")
+        if os.path.exists(self.package_server_log_path()):
+            with open(self.package_server_log_path(), encoding="utf-8") as log:
+                self.log_debug(log.read())
+        else:
+            self.log_debug("No package server log found")
+
+        # Print the ffx daemon log
+        self.log_debug("\n---- ffx daemon log ----\n")
+        if os.path.exists(self.ffx_daemon_log_path()):
+            with open(self.ffx_daemon_log_path(), encoding="utf-8") as log:
+                self.log_debug(log.read())
+        else:
+            self.log_debug("No ffx daemon log found")
+
+        # Stop package server
+        self.log_info("Stopping package server...")
+        os.kill(self.package_server_pid, signal.SIGTERM)
+
+        # Shut down the emulator
+        self.log_info("Stopping emulator...")
+        subprocess.check_call(
+            [
+                self.tool_path("fvdl"),
+                "--sdk",
+                "kill",
+                "--launched-proto",
+                self.vdl_output_path(),
+            ],
+            stdout=self.subprocess_output(),
+            stderr=self.subprocess_output(),
+        )
+
+        # Stop ffx isolation
+        self.log_info("Stopping ffx isolation...")
+        self.stop_ffx_isolation()
+
+    def delete_tmp(self):
+        # Remove temporary files
+        self.log_info("Deleting temporary files...")
+        shutil.rmtree(self.tmp_dir(), ignore_errors=True)
+
+    def debug(self, args):
+        command = [
+            self.tool_path("ffx"),
+            "--config",
+            self.ffx_user_config_path(),
+            "debug",
+            "connect",
+            "--",
+            "--build-id-dir",
+            os.path.join(self.sdk_dir, ".build-id"),
+            "--build-id-dir",
+            os.path.join(self.libs_dir(), ".build-id"),
+        ]
+
+        # Add rust source if it's available
+        if args.rust_src is not None:
+            command += [
+                "--build-dir",
+                args.rust_src,
+            ]
+
+        # Add fuchsia source if it's available
+        if args.fuchsia_src is not None:
+            command += [
+                "--build-dir",
+                os.path.join(args.fuchsia_src, "out", "default"),
+            ]
+
+        # Load debug symbols for the test binary and automatically attach
+        if args.test is not None:
+            if args.rust_src is None:
+                raise Exception(
+                    "A Rust source path is required with the `test` argument"
+                )
+
+            test_name = os.path.splitext(os.path.basename(args.test))[0]
+
+            build_dir = os.path.join(
+                args.rust_src,
+                "fuchsia-build",
+                self.host_arch_triple(),
+            )
+            test_dir = os.path.join(
+                build_dir,
+                "test",
+                os.path.dirname(args.test),
+                test_name,
+            )
+
+            with open(self.zxdb_script_path(), mode="w", encoding="utf-8") as f:
+                print(f"attach {test_name[:31]}", file=f)
+
+            command += [
+                "--symbol-path",
+                test_dir,
+                "-S",
+                self.zxdb_script_path(),
+            ]
+
+        # Add any other zxdb arguments the user passed
+        if args.zxdb_args is not None:
+            command += args.zxdb_args
+
+        # Connect to the running emulator with zxdb
+        subprocess.run(command, env=self.ffx_cmd_env(), check=False)
+
+
+def start(args):
+    test_env = TestEnvironment.from_args(args)
+    test_env.start()
+    return 0
+
+
+def run(args):
+    test_env = TestEnvironment.read_from_file()
+    return test_env.run(args)
+
+
+def stop(args):
+    test_env = TestEnvironment.read_from_file()
+    test_env.stop()
+    if not args.no_delete:
+        test_env.delete_tmp()
+    return 0
+
+
+def delete_tmp(args):
+    del args
+    test_env = TestEnvironment.read_from_file()
+    test_env.delete_tmp()
+    return 0
+
+
+def debug(args):
+    test_env = TestEnvironment.read_from_file()
+    test_env.debug(args)
+    return 0
+
+
+def main():
+    parser = argparse.ArgumentParser()
+
+    def print_help(args):
+        del args
+        parser.print_help()
+        return 0
+
+    parser.set_defaults(func=print_help)
+
+    subparsers = parser.add_subparsers(help="valid sub-commands")
+
+    start_parser = subparsers.add_parser(
+        "start", help="initializes the testing environment"
+    )
+    start_parser.add_argument(
+        "--rust",
+        help="the directory of the installed Rust compiler for Fuchsia",
+        required=True,
+    )
+    start_parser.add_argument(
+        "--sdk",
+        help="the directory of the fuchsia SDK",
+        required=True,
+    )
+    start_parser.add_argument(
+        "--verbose",
+        help="prints more output from executed processes",
+        action="store_true",
+    )
+    start_parser.add_argument(
+        "--target-arch",
+        help="the architecture of the image to test",
+        required=True,
+    )
+    start_parser.set_defaults(func=start)
+
+    run_parser = subparsers.add_parser(
+        "run", help="run a test in the testing environment"
+    )
+    run_parser.add_argument(
+        "n", help="the number of shared libs passed along with the executable", type=int
+    )
+    run_parser.add_argument("bin_path", help="path to the binary to run")
+    run_parser.add_argument(
+        "shared_libs",
+        help="the shared libs passed along with the binary",
+        nargs=argparse.REMAINDER,
+    )
+    run_parser.set_defaults(func=run)
+
+    stop_parser = subparsers.add_parser(
+        "stop", help="shuts down and cleans up the testing environment"
+    )
+    stop_parser.add_argument(
+        "--no-delete",
+        default=False,
+        action="store_true",
+        help="don't delete temporary files after stopping",
+    )
+    stop_parser.set_defaults(func=stop)
+
+    delete_parser = subparsers.add_parser(
+        "delete-tmp",
+        help="deletes temporary files after the testing environment has been manually cleaned up",
+    )
+    delete_parser.set_defaults(func=delete_tmp)
+
+    debug_parser = subparsers.add_parser(
+        "debug",
+        help="connect to the active testing environment with zxdb",
+    )
+    debug_parser.add_argument(
+        "--rust-src",
+        default=None,
+        help="the path to the Rust source being tested",
+    )
+    debug_parser.add_argument(
+        "--fuchsia-src",
+        default=None,
+        help="the path to the Fuchsia source",
+    )
+    debug_parser.add_argument(
+        "--test",
+        default=None,
+        help="the path to the test to debug (e.g. ui/box/new.rs)",
+    )
+    debug_parser.add_argument(
+        "zxdb_args",
+        default=None,
+        nargs=argparse.REMAINDER,
+        help="any additional arguments to pass to zxdb",
+    )
+    debug_parser.set_defaults(func=debug)
+
+    args = parser.parse_args()
+    return args.func(args)
+
+
+if __name__ == "__main__":
+    sys.exit(main())
diff --git a/src/ci/run.sh b/src/ci/run.sh
index 9d98ce22498c..7de06ec35c36 100755
--- a/src/ci/run.sh
+++ b/src/ci/run.sh
@@ -69,11 +69,6 @@ RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --set rust.codegen-units-std=1"
 # space required for CI artifacts.
 RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --dist-compression-formats=xz"
 
-# Enable the `c` feature for compiler_builtins, but only when the `compiler-rt` source is available.
-if [ "$EXTERNAL_LLVM" = "" ]; then
-  RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --set build.optimized-compiler-builtins"
-fi
-
 if [ "$DIST_SRC" = "" ]; then
   RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --disable-dist-src"
 fi
@@ -128,6 +123,10 @@ else
   # (And PGO is its own can of worms).
   if [ "$NO_DOWNLOAD_CI_LLVM" = "" ]; then
     RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --set llvm.download-ci-llvm=if-available"
+  else
+    # When building for CI we want to use the static C++ Standard library
+    # included with LLVM, since a dynamic libstdcpp may not be available.
+    RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --set llvm.static-libstdcpp"
   fi
 fi
 
diff --git a/src/doc/book b/src/doc/book
index f1e5ad844d0c..3f64052c048c 160000
--- a/src/doc/book
+++ b/src/doc/book
@@ -1 +1 @@
-Subproject commit f1e5ad844d0c61738006cdef26227beeb136948e
+Subproject commit 3f64052c048c6def93b94a2b514ee88bba918744
diff --git a/src/doc/nomicon b/src/doc/nomicon
index 9c7328377546..05532356e7a4 160000
--- a/src/doc/nomicon
+++ b/src/doc/nomicon
@@ -1 +1 @@
-Subproject commit 9c73283775466d22208a0b28afcab44db4c0cc10
+Subproject commit 05532356e7a4dbea2330aabb77611f5179493bb8
diff --git a/src/doc/reference b/src/doc/reference
index f6ed74f582bd..9f0cc13ffcd2 160000
--- a/src/doc/reference
+++ b/src/doc/reference
@@ -1 +1 @@
-Subproject commit f6ed74f582bddcec73f753eafaab3749c4f7df61
+Subproject commit 9f0cc13ffcd27c1fbe1ab766a9491e15ddcf4d19
diff --git a/src/doc/rust-by-example b/src/doc/rust-by-example
index 5e7b296d6c34..2b15c0abf2ba 160000
--- a/src/doc/rust-by-example
+++ b/src/doc/rust-by-example
@@ -1 +1 @@
-Subproject commit 5e7b296d6c345addbd748f242aae28c42555c015
+Subproject commit 2b15c0abf2bada6e00553814336bc3e2d8399097
diff --git a/src/doc/rustc-dev-guide b/src/doc/rustc-dev-guide
index 7518c3445dc0..d0dc6c97a648 160000
--- a/src/doc/rustc-dev-guide
+++ b/src/doc/rustc-dev-guide
@@ -1 +1 @@
-Subproject commit 7518c3445dc02df0d196f5f84e568d633c5141fb
+Subproject commit d0dc6c97a6486f68bac782fff135086eae6d77ec
diff --git a/src/doc/rustc/src/SUMMARY.md b/src/doc/rustc/src/SUMMARY.md
index 06883ddd58bc..2d3b83094614 100644
--- a/src/doc/rustc/src/SUMMARY.md
+++ b/src/doc/rustc/src/SUMMARY.md
@@ -29,9 +29,11 @@
     - [\*-kmc-solid_\*](platform-support/kmc-solid.md)
     - [m68k-unknown-linux-gnu](platform-support/m68k-unknown-linux-gnu.md)
     - [mips64-openwrt-linux-musl](platform-support/mips64-openwrt-linux-musl.md)
+    - [mipsel-sony-psx](platform-support/mipsel-sony-psx.md)
     - [nvptx64-nvidia-cuda](platform-support/nvptx64-nvidia-cuda.md)
     - [riscv32imac-unknown-xous-elf](platform-support/riscv32imac-unknown-xous-elf.md)
     - [*-pc-windows-gnullvm](platform-support/pc-windows-gnullvm.md)
+    - [\*-nto-qnx-\*](platform-support/nto-qnx.md)
     - [*-unknown-openbsd](platform-support/openbsd.md)
     - [\*-unknown-uefi](platform-support/unknown-uefi.md)
     - [wasm64-unknown-unknown](platform-support/wasm64-unknown-unknown.md)
diff --git a/src/doc/rustc/src/codegen-options/index.md b/src/doc/rustc/src/codegen-options/index.md
index b1c3b618cec0..f5a49410ea55 100644
--- a/src/doc/rustc/src/codegen-options/index.md
+++ b/src/doc/rustc/src/codegen-options/index.md
@@ -531,8 +531,10 @@ platforms. Possible values are:
   debug information. On other Unix platforms this means that `*.dwo` files will
   contain debug information.
 
-Note that `packed` and `unpacked` are gated behind `-Z unstable-options` on
-non-macOS platforms at this time.
+Note that all three options are supported on Linux and Apple platforms,
+`packed` is supported on Windows-MSVC, and all other platforms support `off`.
+Attempting to use an unsupported option requires using the nightly channel
+with the `-Z unstable-options` flag.
 
 ## strip
 
diff --git a/src/doc/rustc/src/command-line-arguments.md b/src/doc/rustc/src/command-line-arguments.md
index 2d12cf382b16..2dc182b3d83e 100644
--- a/src/doc/rustc/src/command-line-arguments.md
+++ b/src/doc/rustc/src/command-line-arguments.md
@@ -302,7 +302,7 @@ _Note:_ The order of these lint level arguments is taken into account, see [lint
 This flag will allow you to set unstable options of rustc. In order to set multiple options,
 the -Z flag can be used multiple times. For example: `rustc -Z verbose -Z time-passes`.
 Specifying options with -Z is only available on nightly. To view all available options
-run: `rustc -Z help`.
+run: `rustc -Z help`, or see [The Unstable Book](../unstable-book/index.html).
 
 <a id="option-cap-lints"></a>
 ## `--cap-lints`: set the most restrictive lint level
diff --git a/src/doc/rustc/src/linker-plugin-lto.md b/src/doc/rustc/src/linker-plugin-lto.md
index b1854b22a7cd..9272b9ac9b2d 100644
--- a/src/doc/rustc/src/linker-plugin-lto.md
+++ b/src/doc/rustc/src/linker-plugin-lto.md
@@ -131,24 +131,47 @@ able to get around this problem by setting `-Clinker=lld-link` in RUSTFLAGS
 
 ## Toolchain Compatibility
 
-<!-- NOTE: to update the below table, you can use this shell script:
+<!-- NOTE: to update the below table, you can use this Python script:
 
-```sh
-rustup toolchain install --profile minimal nightly
-MINOR_VERSION=$(rustc +nightly --version | cut -d . -f 2)
-LOWER_BOUND=61
+```python
+from collections import defaultdict
+import subprocess
 
-llvm_version() {
-    toolchain="$1"
-    printf "Rust $toolchain    |    Clang "
-    rustc +"$toolchain" -Vv | grep LLVM | cut -d ':' -f 2 | tr -d ' '
-}
+def minor_version(version):
+    return int(version.split('.')[1])
 
-for version in `seq $LOWER_BOUND $((MINOR_VERSION - 2))`; do
-    toolchain=1.$version.0
-    rustup toolchain install --no-self-update --profile  minimal $toolchain >/dev/null 2>&1
-    llvm_version $toolchain
-done
+INSTALL_TOOLCHAIN = ["rustup", "toolchain", "install", "--profile", "minimal"]
+subprocess.run(INSTALL_TOOLCHAIN + ["nightly"])
+
+LOWER_BOUND = 65
+NIGHTLY_VERSION = minor_version(subprocess.run(
+    ["rustc", "+nightly", "--version"],
+    capture_output=True,
+    text=True).stdout)
+
+def llvm_version(toolchain):
+    version_text = subprocess.run(
+        ["rustc", "+{}".format(toolchain), "-Vv"],
+        capture_output=True,
+        text=True).stdout
+    return int(version_text.split("LLVM")[1].split(':')[1].split('.')[0])
+
+version_map = defaultdict(lambda: [])
+for version in range(LOWER_BOUND, NIGHTLY_VERSION - 1):
+    toolchain = "1.{}.0".format(version)
+    subprocess.run(
+        INSTALL_TOOLCHAIN + ["--no-self-update", toolchain],
+        capture_output=True)
+    version_map[llvm_version(toolchain)].append(version)
+
+print("| Rust Version | Clang Version |")
+print("|--------------|---------------|")
+for clang, rust in sorted(version_map.items()):
+    if len(rust) > 1:
+        rust_range = "1.{} - 1.{}".format(rust[0], rust[-1])
+    else:
+        rust_range = "1.{}       ".format(rust[0])
+    print("| {}  |      {}       |".format(rust_range, clang))
 ```
 
 -->
@@ -166,32 +189,13 @@ The following table shows known good combinations of toolchain versions.
 
 | Rust Version | Clang Version |
 |--------------|---------------|
-| Rust 1.34    |    Clang 8    |
-| Rust 1.35    |    Clang 8    |
-| Rust 1.36    |    Clang 8    |
-| Rust 1.37    |    Clang 8    |
-| Rust 1.38    |    Clang 9    |
-| Rust 1.39    |    Clang 9    |
-| Rust 1.40    |    Clang 9    |
-| Rust 1.41    |    Clang 9    |
-| Rust 1.42    |    Clang 9    |
-| Rust 1.43    |    Clang 9    |
-| Rust 1.44    |    Clang 9    |
-| Rust 1.45    |    Clang 10   |
-| Rust 1.46    |    Clang 10   |
-| Rust 1.47    |    Clang 11   |
-| Rust 1.48    |    Clang 11   |
-| Rust 1.49    |    Clang 11   |
-| Rust 1.50    |    Clang 11   |
-| Rust 1.51    |    Clang 11   |
-| Rust 1.52    |    Clang 12   |
-| Rust 1.53    |    Clang 12   |
-| Rust 1.54    |    Clang 12   |
-| Rust 1.55    |    Clang 12   |
-| Rust 1.56    |    Clang 13   |
-| Rust 1.57    |    Clang 13   |
-| Rust 1.58    |    Clang 13   |
-| Rust 1.59    |    Clang 13   |
-| Rust 1.60    |    Clang 14   |
+| 1.34 - 1.37  |       8       |
+| 1.38 - 1.44  |       9       |
+| 1.45 - 1.46  |      10       |
+| 1.47 - 1.51  |      11       |
+| 1.52 - 1.55  |      12       |
+| 1.56 - 1.59  |      13       |
+| 1.60 - 1.64  |      14       |
+| 1.65         |      15       |
 
 Note that the compatibility policy for this feature might change in the future.
diff --git a/src/doc/rustc/src/platform-support.md b/src/doc/rustc/src/platform-support.md
index a36518cc8ce7..28929acb9b48 100644
--- a/src/doc/rustc/src/platform-support.md
+++ b/src/doc/rustc/src/platform-support.md
@@ -128,6 +128,7 @@ target | std | notes
 [`aarch64-linux-android`](platform-support/android.md) | ✓ | ARM64 Android
 `aarch64-unknown-none-softfloat` | * | Bare ARM64, softfloat
 `aarch64-unknown-none` | * | Bare ARM64, hardfloat
+[`aarch64-unknown-uefi`](platform-support/unknown-uefi.md) | * | ARM64 UEFI
 [`arm-linux-androideabi`](platform-support/android.md) | ✓ | ARMv7 Android
 `arm-unknown-linux-musleabi` | ✓ | ARMv6 Linux with MUSL
 `arm-unknown-linux-musleabihf` | ✓ | ARMv6 Linux with MUSL, hardfloat
@@ -149,6 +150,7 @@ target | std | notes
 [`i686-linux-android`](platform-support/android.md) | ✓ | 32-bit x86 Android
 `i686-unknown-freebsd` | ✓ | 32-bit FreeBSD
 `i686-unknown-linux-musl` | ✓ | 32-bit Linux with MUSL
+[`i686-unknown-uefi`](platform-support/unknown-uefi.md) | * | 32-bit UEFI
 `mips-unknown-linux-musl` | ✓ | MIPS Linux with MUSL
 `mips64-unknown-linux-muslabi64` | ✓ | MIPS64 Linux, n64 ABI, MUSL
 `mips64el-unknown-linux-muslabi64` | ✓ | MIPS64 (LE) Linux, n64 ABI, MUSL
@@ -181,6 +183,7 @@ target | std | notes
 `x86_64-unknown-linux-gnux32` | ✓ | 64-bit Linux (x32 ABI) (kernel 4.15, glibc 2.27)
 [`x86_64-unknown-none`](platform-support/x86_64-unknown-none.md) | * | Freestanding/bare-metal x86_64, softfloat
 `x86_64-unknown-redox` | ✓ | Redox OS
+[`x86_64-unknown-uefi`](platform-support/unknown-uefi.md) | * | 64-bit UEFI
 
 [Fortanix ABI]: https://edp.fortanix.com/
 
@@ -211,9 +214,9 @@ target | std | host | notes
 [`aarch64-kmc-solid_asp3`](platform-support/kmc-solid.md) | ✓ |  | ARM64 SOLID with TOPPERS/ASP3
 [`aarch64-nintendo-switch-freestanding`](platform-support/aarch64-nintendo-switch-freestanding.md) | * |  | ARM64 Nintendo Switch, Horizon
 [`aarch64-pc-windows-gnullvm`](platform-support/pc-windows-gnullvm.md) | ✓ | ✓ |
+[`aarch64-unknown-nto-qnx7.1.0`](platform-support/nto-qnx.md) | ? |  | ARM64 QNX Neutrino 7.1 RTOS |
 `aarch64-unknown-freebsd` | ✓ | ✓ | ARM64 FreeBSD
 `aarch64-unknown-hermit` | ✓ |  | ARM64 HermitCore
-[`aarch64-unknown-uefi`](platform-support/unknown-uefi.md) | * |  | ARM64 UEFI
 `aarch64-unknown-linux-gnu_ilp32` | ✓ | ✓ | ARM64 Linux (ILP32 ABI)
 `aarch64-unknown-netbsd` | ✓ | ✓ |
 [`aarch64-unknown-openbsd`](platform-support/openbsd.md) | ✓ | ✓ | ARM64 OpenBSD
@@ -252,7 +255,6 @@ target | std | host | notes
 `i686-unknown-haiku` | ✓ | ✓ | 32-bit Haiku
 `i686-unknown-netbsd` | ✓ | ✓ | NetBSD/i386 with SSE2
 [`i686-unknown-openbsd`](platform-support/openbsd.md) | ✓ | ✓ | 32-bit OpenBSD
-[`i686-unknown-uefi`](platform-support/unknown-uefi.md) | * |  | 32-bit UEFI
 `i686-uwp-windows-gnu` | ? |  |
 `i686-uwp-windows-msvc` | ? |  |
 `i686-wrs-vxworks` | ? |  |
@@ -260,6 +262,7 @@ target | std | host | notes
 `mips-unknown-linux-uclibc` | ✓ |  | MIPS Linux with uClibc
 [`mips64-openwrt-linux-musl`](platform-support/mips64-openwrt-linux-musl.md) | ? |  | MIPS64 for OpenWrt Linux MUSL
 `mipsel-sony-psp` | * |  | MIPS (LE) Sony PlayStation Portable (PSP)
+[`mipsel-sony-psx`](platform-support/mipsel-sony-psx.md) | * |  | MIPS (LE) Sony PlayStation 1 (PSX)
 `mipsel-unknown-linux-uclibc` | ✓ |  | MIPS (LE) Linux with uClibc
 `mipsel-unknown-none` | * |  | Bare MIPS (LE) softfloat
 `mipsisa32r6-unknown-linux-gnu` | ? |  |
@@ -301,6 +304,7 @@ target | std | host | notes
 `x86_64-apple-ios-macabi` | ✓ |  | Apple Catalyst on x86_64
 `x86_64-apple-tvos` | * | | x86 64-bit tvOS
 [`x86_64-apple-watchos-sim`](platform-support/apple-watchos.md) | ✓ | | x86 64-bit Apple WatchOS simulator
+[`x86_64-pc-nto-qnx7.1.0`](platform-support/nto-qnx.md) | ? |  | x86 64-bit QNX Neutrino 7.1 RTOS |
 [`x86_64-pc-windows-gnullvm`](platform-support/pc-windows-gnullvm.md) | ✓ | ✓ |
 `x86_64-pc-windows-msvc` | * |  | 64-bit Windows XP support
 `x86_64-sun-solaris` | ? |  | Deprecated target for 64-bit Solaris 10/11, illumos
@@ -308,9 +312,7 @@ target | std | host | notes
 `x86_64-unknown-haiku` | ✓ | ✓ | 64-bit Haiku
 `x86_64-unknown-hermit` | ✓ |  | HermitCore
 `x86_64-unknown-l4re-uclibc` | ? |  |
-`x86_64-unknown-none-linuxkernel` | * |  | Linux kernel modules
 [`x86_64-unknown-openbsd`](platform-support/openbsd.md) | ✓ | ✓ | 64-bit OpenBSD
-[`x86_64-unknown-uefi`](platform-support/unknown-uefi.md) | * |  | 64-bit UEFI
 `x86_64-uwp-windows-gnu` | ✓ |  |
 `x86_64-uwp-windows-msvc` | ✓ |  |
 `x86_64-wrs-vxworks` | ? |  |
diff --git a/src/doc/rustc/src/platform-support/fuchsia.md b/src/doc/rustc/src/platform-support/fuchsia.md
index 1ff6003c121c..62cad19d0ec3 100644
--- a/src/doc/rustc/src/platform-support/fuchsia.md
+++ b/src/doc/rustc/src/platform-support/fuchsia.md
@@ -641,8 +641,60 @@ available on the [Fuchsia devsite].
 
 ### Running the compiler test suite
 
-Running the Rust test suite on Fuchsia is [not currently supported], but work is
-underway to enable it.
+Pre-requisites for running the Rust test suite on Fuchsia are:
+1. Checkout of Rust source.
+1. Setup of `config-env.sh` and `config.toml` from "[Targeting Fuchsia with a compiler built from source](#targeting-fuchsia-with-a-compiler-built-from-source)".
+1. Download of the Fuchsia SDK. Minimum supported SDK version is [9.20220726.1.1](https://chrome-infra-packages.appspot.com/p/fuchsia/sdk/core/linux-amd64/+/version:9.20220726.1.1)
+
+Interfacing with the Fuchsia emulator is handled by our test runner script located
+at `${RUST_SRC_PATH}/src/ci/docker/scripts/fuchsia-test-runner.py`.
+
+We start by activating our Fuchsia test environment. From a terminal:
+
+**Issue command from ${RUST_SRC_PATH}**
+```sh
+src/ci/docker/scripts/fuchsia-test-runner.py start
+    --rust .
+    --sdk ${SDK_PATH}
+    --target-arch {x64,arm64}
+```
+
+Next, for ease of commands, we copy `config-env.sh` and `config.toml` into our Rust source
+code path, `${RUST_SRC_PATH}`.
+
+From there, we utilize `x.py` to run our tests, using the test runner script to
+run the tests on our emulator. To run the full `src/test/ui` test suite:
+
+**Run from ${RUST_SRC_PATH}**
+```sh
+( \
+    source config-env.sh &&                                                   \
+    ./x.py                                                                    \
+    --config config.toml                                                      \
+    --stage=2                                                                 \
+    test src/test/ui                                                          \
+    --target x86_64-fuchsia                                                   \
+    --run=always --jobs 1                                                     \
+    --test-args --target-rustcflags -L                                        \
+    --test-args --target-rustcflags ${SDK_PATH}/arch/{x64|arm64}/sysroot/lib  \
+    --test-args --target-rustcflags -L                                        \
+    --test-args --target-rustcflags ${SDK_PATH}/arch/{x64|arm64}/lib          \
+    --test-args --target-rustcflags -Cpanic=abort                             \
+    --test-args --target-rustcflags -Zpanic_abort_tests                       \
+    --test-args --remote-test-client                                          \
+    --test-args src/ci/docker/scripts/fuchsia-test-runner.py                  \
+)
+```
+
+*Note: The test suite cannot be run in parallel at the moment, so `x.py`
+must be run with `--jobs 1` to ensure only one test runs at a time.*
+
+When finished, stop the test environment:
+
+**Issue command from ${RUST_SRC_PATH}**
+```sh
+src/ci/docker/scripts/fuchsia-test-runner.py stop
+```
 
 ## Debugging
 
diff --git a/src/doc/rustc/src/platform-support/mipsel-sony-psx.md b/src/doc/rustc/src/platform-support/mipsel-sony-psx.md
new file mode 100644
index 000000000000..589100e8888b
--- /dev/null
+++ b/src/doc/rustc/src/platform-support/mipsel-sony-psx.md
@@ -0,0 +1,49 @@
+# mipsel-sony-psx
+
+**Tier: 3**
+
+Sony PlayStation 1 (psx)
+
+## Designated Developer
+
+* [@ayrtonm](https://github.com/ayrtonm)
+
+## Requirements
+
+This target is cross-compiled.
+It has no special requirements for the host.
+
+## Building
+
+The target can be built by enabling it for a `rustc` build:
+
+```toml
+[build]
+build-stage = 1
+target = ["mipsel-sony-psx"]
+```
+
+## Cross-compilation
+
+This target can be cross-compiled from any host.
+
+## Testing
+
+Currently there is no support to run the rustc test suite for this target.
+
+## Building Rust programs
+
+Since it is Tier 3, rust doesn't ship pre-compiled artifacts for this target.
+
+Just use the `build-std` nightly cargo feature to build the `core` and `alloc` libraries:
+```shell
+cargo build -Zbuild-std=core,alloc --target mipsel-sony-psx
+```
+
+The command above generates an ELF. To generate binaries in the PSEXE format that emulators run, you can use [cargo-psx](https://github.com/ayrtonm/psx-sdk-rs#readme):
+
+```shell
+cargo psx build
+```
+
+or use `-Clink-arg=--oformat=binary` to produce a flat binary.
diff --git a/src/doc/rustc/src/platform-support/nto-qnx.md b/src/doc/rustc/src/platform-support/nto-qnx.md
new file mode 100644
index 000000000000..2f6ea94d113a
--- /dev/null
+++ b/src/doc/rustc/src/platform-support/nto-qnx.md
@@ -0,0 +1,118 @@
+# nto-qnx
+
+**Tier: 3**
+
+[BlackBerry® QNX®][BlackBerry] Neutrino (nto) Real-time operating system.
+The support has been implemented jointly by [Elektrobit Automotive GmbH][Elektrobit]
+and [BlackBerry][BlackBerry].
+
+[BlackBerry]: https://blackberry.qnx.com
+[Elektrobit]: https://www.elektrobit.com
+
+## Target maintainers
+
+- Florian Bartels, `Florian.Bartels@elektrobit.com`, https://github.com/flba-eb
+- Tristan Roach, `TRoach@blackberry.com`, https://github.com/gh-tr
+
+## Requirements
+
+Currently, only cross-compilation for QNX Neutrino on AArch64 and x86_64 are supported (little endian).
+Adding other architectures that are supported by QNX Neutrino is possible.
+
+The standard library does not yet support QNX Neutrino. Therefore, only `no_std` code can
+be compiled.
+
+`core` and `alloc` (with default allocator) are supported.
+
+Applications must link against `libc.so` (see example). This is required because applications
+always link against the `crt` library and `crt` depends on `libc.so`.
+
+The correct version of `qcc` must be available by setting the `$PATH` variable (e.g. by sourcing `qnxsdp-env.sh` of the
+QNX Neutrino toolchain).
+
+### Small example application
+
+```rust,ignore (platform-specific)
+#![no_std]
+#![no_main]
+#![feature(lang_items)]
+
+// We must always link against libc, even if no external functions are used
+// "extern C" - Block can be empty but must be present
+#[link(name = "c")]
+extern "C" {
+    pub fn printf(format: *const core::ffi::c_char, ...) -> core::ffi::c_int;
+}
+
+#[no_mangle]
+pub extern "C" fn main(_argc: isize, _argv: *const *const u8) -> isize {
+    const HELLO: &'static str = "Hello World, the answer is %d\n\0";
+    unsafe {
+        printf(HELLO.as_ptr() as *const _, 42);
+    }
+    0
+}
+
+use core::panic::PanicInfo;
+
+#[panic_handler]
+fn panic(_panic: &PanicInfo<'_>) -> ! {
+    loop {}
+}
+
+#[lang = "eh_personality"]
+#[no_mangle]
+pub extern "C" fn rust_eh_personality() {}
+```
+
+The QNX Neutrino support of Rust has been tested with QNX Neutrino 7.1.
+
+There are no further known requirements.
+
+## Conditional compilation
+
+For conditional compilation, following QNX Neutrino specific attributes are defined:
+
+- `target_os` = `"nto"`
+- `target_env` = `"nto71"` (for QNX Neutrino 7.1)
+
+## Building the target
+
+1. Create a `config.toml`
+
+Example content:
+
+```toml
+profile = "compiler"
+changelog-seen = 2
+```
+
+2. Compile the Rust toolchain for an `x86_64-unknown-linux-gnu` host (for both `aarch64` and `x86_64` targets)
+
+Run the following:
+
+```bash
+env \
+    CC_aarch64-unknown-nto-qnx7.1.0="qcc" \
+    CFLAGS_aarch64-unknown-nto-qnx7.1.0="-Vgcc_ntoaarch64le_cxx" \
+    CXX_aarch64-unknown-nto-qnx7.1.0="qcc" \
+    AR_aarch64_unknown_nto_qnx7.1.0="ntoaarch64-ar" \
+    CC_x86_64-pc-nto-qnx7.1.0="qcc" \
+    CFLAGS_x86_64-pc-nto-qnx7.1.0="-Vgcc_ntox86_64_cxx" \
+    CXX_x86_64-pc-nto-qnx7.1.0="qcc" \
+    AR_x86_64_pc_nto_qnx7.1.0="ntox86_64-ar" \
+        ./x.py build --target aarch64-unknown-nto-qnx7.1.0 --target x86_64-pc-nto-qnx7.1.0 --target x86_64-unknown-linux-gnu rustc library/core library/alloc/
+```
+
+## Building Rust programs
+
+Rust does not yet ship pre-compiled artifacts for this target. To compile for this target, you must either build Rust with the target enabled (see "Building the target" above), or build your own copy of  `core` by using
+`build-std` or similar.
+
+## Testing
+
+Compiled executables can directly be run on QNX Neutrino.
+
+## Cross-compilation toolchains and C code
+
+Compiling C code requires the same environment variables to be set as compiling the Rust toolchain (see above), to ensure `qcc` is used with proper arguments. To ensure compatibility, do not specify any further arguments that for example change calling conventions or memory layout.
diff --git a/src/doc/rustc/src/platform-support/unknown-uefi.md b/src/doc/rustc/src/platform-support/unknown-uefi.md
index 295dec0f0e48..e2bdf73a9299 100644
--- a/src/doc/rustc/src/platform-support/unknown-uefi.md
+++ b/src/doc/rustc/src/platform-support/unknown-uefi.md
@@ -1,6 +1,6 @@
 # `*-unknown-uefi`
 
-**Tier: 3**
+**Tier: 2**
 
 Unified Extensible Firmware Interface (UEFI) targets for application, driver,
 and core UEFI binaries.
@@ -72,28 +72,14 @@ target = ["x86_64-unknown-uefi"]
 
 ## Building Rust programs
 
-Rust does not yet ship pre-compiled artifacts for this target. To compile for
-this target, you will either need to build Rust with the target enabled (see
-"Building rust for UEFI targets" above), or build your own copy of `core` by
-using `build-std`, `cargo-buildx`, or similar.
-
-A native build with the unstable `build-std`-feature can be achieved via:
+Starting with Rust 1.67, precompiled artifacts are provided via
+`rustup`. For example, to use `x86_64-unknown-uefi`:
 
 ```sh
-cargo +nightly build \
-    -Zbuild-std=core,compiler_builtins \
-    -Zbuild-std-features=compiler-builtins-mem \
-    --target x86_64-unknown-uefi
-```
-
-Alternatively, you can install `cargo-xbuild` via
-`cargo install --force cargo-xbuild` and build for the UEFI targets via:
-
-```sh
-cargo \
-    +nightly \
-    xbuild \
-    --target x86_64-unknown-uefi
+# install cross-compile toolchain
+rustup target add x86_64-unknown-uefi
+# target flag may be used with any cargo or rustc command
+cargo build --target x86_64-unknown-uefi
 ```
 
 ## Testing
@@ -167,18 +153,10 @@ The following code is a valid UEFI application returning immediately upon
 execution with an exit code of 0. A panic handler is provided. This is executed
 by rust on panic. For simplicity, we simply end up in an infinite loop.
 
-Note that as of rust-1.31.0, all features used here are stabilized. No unstable
-features are required, nor do we rely on nightly compilers. However, if you do
-not compile rustc for the UEFI targets, you need a nightly compiler to support
-the `-Z build-std` flag.
-
 This example can be compiled as binary crate via `cargo`:
 
 ```sh
-cargo +nightly build \
-    -Zbuild-std=core,compiler_builtins \
-    -Zbuild-std-features=compiler-builtins-mem \
-    --target x86_64-unknown-uefi
+cargo build --target x86_64-unknown-uefi
 ```
 
 ```rust,ignore (platform-specific,eh-personality-is-unstable)
diff --git a/src/doc/rustc/src/target-tier-policy.md b/src/doc/rustc/src/target-tier-policy.md
index 53d0470fa813..df9131ce84af 100644
--- a/src/doc/rustc/src/target-tier-policy.md
+++ b/src/doc/rustc/src/target-tier-policy.md
@@ -3,6 +3,7 @@
 ## Table of Contents
 
 * [General](#general)
+* [Adding a new target](#adding-a-new-target)
 * [Tier 3 target policy](#tier-3-target-policy)
 * [Tier 2 target policy](#tier-2-target-policy)
   * [Tier 2 with host tools](#tier-2-with-host-tools)
@@ -104,6 +105,30 @@ indicates something entirely optional, and does not indicate guidance or
 recommendations. This language is based on [IETF RFC
 2119](https://tools.ietf.org/html/rfc2119).
 
+## Adding a new target
+
+New targets typically start as Tier 3 and then can be promoted later.
+To propose addition of a new target, open a pull request on [`rust-lang/rust`]:
+
+- Copy the [Tier 3 target policy](#tier-3-target-policy) to the description
+  and fill it out, see [example][tier3example].
+- Add a new description for the target in `src/doc/rustc/src/platform-support`
+  using the [template][platform_template].
+- Add the target to the [SUMMARY.md][summary] (allows wildcards) and
+  [platform-support.md][platformsupport] (must name all targets verbatim).
+  Link to the created description page.
+- Ensure the pull request is assigned to a member of the [Rust compiler team][rust_compiler_team] by commenting:
+  ```text
+  r? compiler-team
+  ```
+
+[tier3example]: https://github.com/rust-lang/rust/pull/94872
+[platform_template]: https://github.com/rust-lang/rust/blob/master/src/doc/rustc/src/platform-support/TEMPLATE.md
+[summary]: https://github.com/rust-lang/rust/blob/master/src/doc/rustc/src/SUMMARY.md
+[platformsupport]: https://github.com/rust-lang/rust/blob/master/src/doc/rustc/src/platform-support.md
+[rust_compiler_team]: https://www.rust-lang.org/governance/teams/compiler
+[`rust-lang/rust`]: https://github.com/rust-lang/rust
+
 ## Tier 3 target policy
 
 At this tier, the Rust project provides no official support for a target, so we
diff --git a/src/doc/rustdoc/book.toml b/src/doc/rustdoc/book.toml
index 45405a11765c..dfa685785008 100644
--- a/src/doc/rustdoc/book.toml
+++ b/src/doc/rustdoc/book.toml
@@ -6,5 +6,9 @@ title = "The rustdoc book"
 git-repository-url = "https://github.com/rust-lang/rust/tree/master/src/doc/rustdoc"
 
 [output.html.redirect]
+"/what-to-include.html" = "write-documentation/what-to-include.html"
 "/the-doc-attribute.html" = "write-documentation/the-doc-attribute.html"
+"/linking-to-items-by-name.html" = "write-documentation/linking-to-items-by-name.html"
 "/documentation-tests.html" = "write-documentation/documentation-tests.html"
+"/website-features.html" = "advanced-features.html#custom-search-engines"
+"/passes.html" = "deprecated-features.html#passes"
diff --git a/src/doc/unstable-book/src/language-features/arbitrary-enum-discriminant.md b/src/doc/unstable-book/src/language-features/arbitrary-enum-discriminant.md
deleted file mode 100644
index e0bb782270e2..000000000000
--- a/src/doc/unstable-book/src/language-features/arbitrary-enum-discriminant.md
+++ /dev/null
@@ -1,37 +0,0 @@
-# `arbitrary_enum_discriminant`
-
-The tracking issue for this feature is: [#60553]
-
-[#60553]: https://github.com/rust-lang/rust/issues/60553
-
-------------------------
-
-The `arbitrary_enum_discriminant` feature permits tuple-like and
-struct-like enum variants with `#[repr(<int-type>)]` to have explicit discriminants.
-
-## Examples
-
-```rust
-#![feature(arbitrary_enum_discriminant)]
-
-#[allow(dead_code)]
-#[repr(u8)]
-enum Enum {
-    Unit = 3,
-    Tuple(u16) = 2,
-    Struct {
-        a: u8,
-        b: u16,
-    } = 1,
-}
-
-impl Enum {
-    fn tag(&self) -> u8 {
-        unsafe { *(self as *const Self as *const u8) }
-    }
-}
-
-assert_eq!(3, Enum::Unit.tag());
-assert_eq!(2, Enum::Tuple(5).tag());
-assert_eq!(1, Enum::Struct{a: 7, b: 11}.tag());
-```
diff --git a/src/doc/unstable-book/src/language-features/extended-varargs-abi-support.md b/src/doc/unstable-book/src/language-features/extended-varargs-abi-support.md
new file mode 100644
index 000000000000..b20c30ec8f1c
--- /dev/null
+++ b/src/doc/unstable-book/src/language-features/extended-varargs-abi-support.md
@@ -0,0 +1,10 @@
+# `extended_varargs_abi_support`
+
+The tracking issue for this feature is: [#100189]
+
+[#100189]: https://github.com/rust-lang/rust/issues/100189
+
+------------------------
+
+This feature adds the possibility of using `sysv64`, `win64` or `efiapi` calling
+conventions on functions with varargs.
diff --git a/src/etc/natvis/intrinsic.natvis b/src/etc/natvis/intrinsic.natvis
index 277e57aaf6fc..8c16a562e349 100644
--- a/src/etc/natvis/intrinsic.natvis
+++ b/src/etc/natvis/intrinsic.natvis
@@ -1,6 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <AutoVisualizer xmlns="http://schemas.microsoft.com/vstudio/debugger/natvis/2010">
-  <Type Name="str">
+  <Type Name="ref$&lt;str$&gt;">
+    <AlternativeType Name="ref_mut$&lt;str$&gt;" />
+    <AlternativeType Name="ptr_const$&lt;str$&gt;" />
+    <AlternativeType Name="ptr_mut$&lt;str$&gt;" />
+
     <DisplayString>{(char*)data_ptr,[length]s8}</DisplayString>
     <StringView>(char*)data_ptr,[length]s8</StringView>
     <Expand>
@@ -15,7 +19,11 @@
       </Synthetic>
     </Expand>
   </Type>
-  <Type Name="slice$&lt;*&gt;">
+  <Type Name="ref$&lt;slice2$&lt;*&gt; &gt;">
+    <AlternativeType Name="ref_mut$&lt;slice2$&lt;*&gt; &gt;" />
+    <AlternativeType Name="ptr_const$&lt;slice2$&lt;*&gt; &gt;" />
+    <AlternativeType Name="ptr_mut$&lt;slice2$&lt;*&gt; &gt;" />
+
     <DisplayString>{{ len={length} }}</DisplayString>
     <Expand>
       <Item Name="[len]" ExcludeView="simple">length</Item>
diff --git a/src/etc/natvis/liballoc.natvis b/src/etc/natvis/liballoc.natvis
index bf6c02b91461..41f4a3767f59 100644
--- a/src/etc/natvis/liballoc.natvis
+++ b/src/etc/natvis/liballoc.natvis
@@ -85,7 +85,7 @@
   </Type>
 
   <!-- alloc::rc::Rc<[T]> -->
-  <Type Name="alloc::rc::Rc&lt;slice$&lt;*&gt; &gt;">
+  <Type Name="alloc::rc::Rc&lt;slice2$&lt;*&gt; &gt;">
     <DisplayString>{{ len={ptr.pointer.length} }}</DisplayString>
     <Expand>
       <Item Name="[Length]" ExcludeView="simple">ptr.pointer.length</Item>
@@ -115,7 +115,7 @@
   </Type>
 
   <!-- alloc::rc::Weak<[T]> -->
-  <Type Name="alloc::rc::Weak&lt;slice$&lt;*&gt; &gt;">
+  <Type Name="alloc::rc::Weak&lt;slice2$&lt;*&gt; &gt;">
     <DisplayString>{{ len={ptr.pointer.length} }}</DisplayString>
     <Expand>
       <Item Name="[Length]" ExcludeView="simple">ptr.pointer.length</Item>
@@ -144,7 +144,7 @@
   </Type>
 
   <!-- alloc::sync::Arc<[T]> -->
-  <Type Name="alloc::sync::Arc&lt;slice$&lt;*&gt; &gt;">
+  <Type Name="alloc::sync::Arc&lt;slice2$&lt;*&gt; &gt;">
     <DisplayString>{{ len={ptr.pointer.length} }}</DisplayString>
     <Expand>
       <Item Name="[Length]" ExcludeView="simple">ptr.pointer.length</Item>
@@ -173,7 +173,7 @@
   </Type>
 
   <!-- alloc::sync::Weak<[T]> -->
-  <Type Name="alloc::sync::Weak&lt;slice$&lt;*&gt; &gt;">
+  <Type Name="alloc::sync::Weak&lt;slice2$&lt;*&gt; &gt;">
     <DisplayString>{{ len={ptr.pointer.length} }}</DisplayString>
     <Expand>
       <Item Name="[Length]" ExcludeView="simple">ptr.pointer.length</Item>
diff --git a/src/librustdoc/Cargo.toml b/src/librustdoc/Cargo.toml
index 7bc35c7d5516..0da69202e679 100644
--- a/src/librustdoc/Cargo.toml
+++ b/src/librustdoc/Cargo.toml
@@ -20,7 +20,7 @@ serde_json = "1.0"
 serde = { version = "1.0", features = ["derive"] }
 smallvec = "1.8.1"
 tempfile = "3"
-thin-vec = "0.2.8"
+thin-vec = "0.2.9"
 tracing = "0.1"
 tracing-tree = "0.2.0"
 
diff --git a/src/librustdoc/clean/auto_trait.rs b/src/librustdoc/clean/auto_trait.rs
index efa9242a4678..85bd8446640d 100644
--- a/src/librustdoc/clean/auto_trait.rs
+++ b/src/librustdoc/clean/auto_trait.rs
@@ -3,6 +3,7 @@ use rustc_hir as hir;
 use rustc_hir::lang_items::LangItem;
 use rustc_middle::ty::{self, Region, RegionVid, TypeFoldable, TypeSuperFoldable};
 use rustc_trait_selection::traits::auto_trait::{self, AutoTraitResult};
+use thin_vec::ThinVec;
 
 use std::fmt::Debug;
 
@@ -110,7 +111,7 @@ where
                 );
                 let params = raw_generics.params;
 
-                Generics { params, where_predicates: Vec::new() }
+                Generics { params, where_predicates: ThinVec::new() }
             }
             AutoTraitResult::ExplicitImpl => return None,
         };
@@ -118,7 +119,6 @@ where
         Some(Item {
             name: None,
             attrs: Default::default(),
-            visibility: Inherited,
             item_id: ItemId::Auto { trait_: trait_def_id, for_: item_def_id },
             kind: Box::new(ImplItem(Box::new(Impl {
                 unsafety: hir::Unsafety::Normal,
@@ -130,6 +130,7 @@ where
                 kind: ImplKind::Auto,
             }))),
             cfg: None,
+            inline_stmt_id: None,
         })
     }
 
@@ -148,7 +149,7 @@ where
             })
             .collect();
         // We are only interested in case the type *doesn't* implement the Sized trait.
-        if !ty.is_sized(tcx.at(rustc_span::DUMMY_SP), param_env) {
+        if !ty.is_sized(tcx, param_env) {
             // In case `#![no_core]` is used, `sized_trait` returns nothing.
             if let Some(item) = tcx.lang_items().sized_trait().and_then(|sized_trait_did| {
                 self.generate_for_trait(ty, sized_trait_did, param_env, item_def_id, &f, true)
@@ -183,7 +184,7 @@ where
     fn handle_lifetimes<'cx>(
         regions: &RegionConstraintData<'cx>,
         names_map: &FxHashMap<Symbol, Lifetime>,
-    ) -> Vec<WherePredicate> {
+    ) -> ThinVec<WherePredicate> {
         // Our goal is to 'flatten' the list of constraints by eliminating
         // all intermediate RegionVids. At the end, all constraints should
         // be between Regions (aka region variables). This gives us the information
@@ -335,10 +336,7 @@ where
                 match br {
                     // We only care about named late bound regions, as we need to add them
                     // to the 'for<>' section
-                    ty::BrNamed(_, name) => Some(GenericParamDef {
-                        name,
-                        kind: GenericParamDefKind::Lifetime { outlives: vec![] },
-                    }),
+                    ty::BrNamed(_, name) => Some(GenericParamDef::lifetime(name)),
                     _ => None,
                 }
             })
@@ -429,7 +427,7 @@ where
         &mut self,
         item_def_id: DefId,
         param_env: ty::ParamEnv<'tcx>,
-        mut existing_predicates: Vec<WherePredicate>,
+        mut existing_predicates: ThinVec<WherePredicate>,
         vid_to_region: FxHashMap<ty::RegionVid, ty::Region<'tcx>>,
     ) -> Generics {
         debug!(
@@ -663,7 +661,7 @@ where
     /// both for visual consistency between 'rustdoc' runs, and to
     /// make writing tests much easier
     #[inline]
-    fn sort_where_predicates(&self, predicates: &mut Vec<WherePredicate>) {
+    fn sort_where_predicates(&self, predicates: &mut [WherePredicate]) {
         // We should never have identical bounds - and if we do,
         // they're visually identical as well. Therefore, using
         // an unstable sort is fine.
@@ -710,7 +708,7 @@ where
     /// approach is probably somewhat slower, but the small number of items
     /// involved (impls rarely have more than a few bounds) means that it
     /// shouldn't matter in practice.
-    fn unstable_debug_sort<T: Debug>(&self, vec: &mut Vec<T>) {
+    fn unstable_debug_sort<T: Debug>(&self, vec: &mut [T]) {
         vec.sort_by_cached_key(|x| format!("{:?}", x))
     }
 
diff --git a/src/librustdoc/clean/blanket_impl.rs b/src/librustdoc/clean/blanket_impl.rs
index 7c59e785752d..d80637055829 100644
--- a/src/librustdoc/clean/blanket_impl.rs
+++ b/src/librustdoc/clean/blanket_impl.rs
@@ -20,7 +20,7 @@ impl<'a, 'tcx> BlanketImplFinder<'a, 'tcx> {
         trace!("get_blanket_impls({:?})", ty);
         let mut impls = Vec::new();
         for trait_def_id in cx.tcx.all_traits() {
-            if !cx.cache.access_levels.is_public(trait_def_id)
+            if !cx.cache.effective_visibilities.is_directly_public(cx.tcx, trait_def_id)
                 || cx.generated_synthetics.get(&(ty.0, trait_def_id)).is_some()
             {
                 continue;
@@ -97,7 +97,6 @@ impl<'a, 'tcx> BlanketImplFinder<'a, 'tcx> {
                 impls.push(Item {
                     name: None,
                     attrs: Default::default(),
-                    visibility: Inherited,
                     item_id: ItemId::Blanket { impl_id: impl_def_id, for_: item_def_id },
                     kind: Box::new(ImplItem(Box::new(Impl {
                         unsafety: hir::Unsafety::Normal,
@@ -128,6 +127,7 @@ impl<'a, 'tcx> BlanketImplFinder<'a, 'tcx> {
                         ))),
                     }))),
                     cfg: None,
+                    inline_stmt_id: None,
                 });
             }
         }
diff --git a/src/librustdoc/clean/inline.rs b/src/librustdoc/clean/inline.rs
index 432d318907fa..3fc4aae923a6 100644
--- a/src/librustdoc/clean/inline.rs
+++ b/src/librustdoc/clean/inline.rs
@@ -3,7 +3,7 @@
 use std::iter::once;
 use std::sync::Arc;
 
-use thin_vec::ThinVec;
+use thin_vec::{thin_vec, ThinVec};
 
 use rustc_ast as ast;
 use rustc_data_structures::fx::FxHashSet;
@@ -19,8 +19,7 @@ use rustc_span::symbol::{kw, sym, Symbol};
 use crate::clean::{
     self, clean_fn_decl_from_did_and_sig, clean_generics, clean_impl_item, clean_middle_assoc_item,
     clean_middle_field, clean_middle_ty, clean_trait_ref_with_bindings, clean_ty,
-    clean_ty_generics, clean_variant_def, clean_visibility, utils, Attributes, AttributesExt,
-    ImplKind, ItemId, Type, Visibility,
+    clean_ty_generics, clean_variant_def, utils, Attributes, AttributesExt, ImplKind, ItemId, Type,
 };
 use crate::core::DocContext;
 use crate::formats::item_type::ItemType;
@@ -55,12 +54,39 @@ pub(crate) fn try_inline(
     let mut ret = Vec::new();
 
     debug!("attrs={:?}", attrs);
-    let attrs_clone = attrs;
+
+    let attrs_without_docs = attrs.map(|attrs| {
+        attrs.into_iter().filter(|a| a.doc_str().is_none()).cloned().collect::<Vec<_>>()
+    });
+    // We need this ugly code because:
+    //
+    // ```
+    // attrs_without_docs.map(|a| a.as_slice())
+    // ```
+    //
+    // will fail because it returns a temporary slice and:
+    //
+    // ```
+    // attrs_without_docs.map(|s| {
+    //     vec = s.as_slice();
+    //     vec
+    // })
+    // ```
+    //
+    // will fail because we're moving an uninitialized variable into a closure.
+    let vec;
+    let attrs_without_docs = match attrs_without_docs {
+        Some(s) => {
+            vec = s;
+            Some(vec.as_slice())
+        }
+        None => None,
+    };
 
     let kind = match res {
         Res::Def(DefKind::Trait, did) => {
             record_extern_fqn(cx, did, ItemType::Trait);
-            build_impls(cx, Some(parent_module), did, attrs, &mut ret);
+            build_impls(cx, Some(parent_module), did, attrs_without_docs, &mut ret);
             clean::TraitItem(Box::new(build_external_trait(cx, did)))
         }
         Res::Def(DefKind::Fn, did) => {
@@ -69,27 +95,27 @@ pub(crate) fn try_inline(
         }
         Res::Def(DefKind::Struct, did) => {
             record_extern_fqn(cx, did, ItemType::Struct);
-            build_impls(cx, Some(parent_module), did, attrs, &mut ret);
+            build_impls(cx, Some(parent_module), did, attrs_without_docs, &mut ret);
             clean::StructItem(build_struct(cx, did))
         }
         Res::Def(DefKind::Union, did) => {
             record_extern_fqn(cx, did, ItemType::Union);
-            build_impls(cx, Some(parent_module), did, attrs, &mut ret);
+            build_impls(cx, Some(parent_module), did, attrs_without_docs, &mut ret);
             clean::UnionItem(build_union(cx, did))
         }
         Res::Def(DefKind::TyAlias, did) => {
             record_extern_fqn(cx, did, ItemType::Typedef);
-            build_impls(cx, Some(parent_module), did, attrs, &mut ret);
+            build_impls(cx, Some(parent_module), did, attrs_without_docs, &mut ret);
             clean::TypedefItem(build_type_alias(cx, did))
         }
         Res::Def(DefKind::Enum, did) => {
             record_extern_fqn(cx, did, ItemType::Enum);
-            build_impls(cx, Some(parent_module), did, attrs, &mut ret);
+            build_impls(cx, Some(parent_module), did, attrs_without_docs, &mut ret);
             clean::EnumItem(build_enum(cx, did))
         }
         Res::Def(DefKind::ForeignTy, did) => {
             record_extern_fqn(cx, did, ItemType::ForeignType);
-            build_impls(cx, Some(parent_module), did, attrs, &mut ret);
+            build_impls(cx, Some(parent_module), did, attrs_without_docs, &mut ret);
             clean::ForeignTypeItem
         }
         // Never inline enum variants but leave them shown as re-exports.
@@ -123,20 +149,12 @@ pub(crate) fn try_inline(
         _ => return None,
     };
 
-    let (attrs, cfg) = merge_attrs(cx, Some(parent_module), load_attrs(cx, did), attrs_clone);
+    let (attrs, cfg) = merge_attrs(cx, Some(parent_module), load_attrs(cx, did), attrs);
     cx.inlined.insert(did.into());
-    let mut item = clean::Item::from_def_id_and_attrs_and_parts(
-        did,
-        Some(name),
-        kind,
-        Box::new(attrs),
-        cx,
-        cfg,
-    );
-    if let Some(import_def_id) = import_def_id {
-        // The visibility needs to reflect the one from the reexport and not from the "source" DefId.
-        item.visibility = clean_visibility(cx.tcx.visibility(import_def_id));
-    }
+    let mut item =
+        clean::Item::from_def_id_and_attrs_and_parts(did, Some(name), kind, Box::new(attrs), cfg);
+    // The visibility needs to reflect the one from the reexport and not from the "source" DefId.
+    item.inline_stmt_id = import_def_id;
     ret.push(item);
     Some(ret)
 }
@@ -212,13 +230,7 @@ pub(crate) fn build_external_trait(cx: &mut DocContext<'_>, did: DefId) -> clean
         .tcx
         .associated_items(did)
         .in_definition_order()
-        .map(|item| {
-            // When building an external trait, the cleaned trait will have all items public,
-            // which causes methods to have a `pub` prefix, which is invalid since items in traits
-            // can not have a visibility prefix. Thus we override the visibility here manually.
-            // See https://github.com/rust-lang/rust/issues/81274
-            clean::Item { visibility: Visibility::Inherited, ..clean_middle_assoc_item(item, cx) }
-        })
+        .map(|item| clean_middle_assoc_item(item, cx))
         .collect();
 
     let predicates = cx.tcx.predicates_of(did);
@@ -231,10 +243,19 @@ pub(crate) fn build_external_trait(cx: &mut DocContext<'_>, did: DefId) -> clean
 fn build_external_function<'tcx>(cx: &mut DocContext<'tcx>, did: DefId) -> Box<clean::Function> {
     let sig = cx.tcx.fn_sig(did);
 
-    let predicates = cx.tcx.predicates_of(did);
+    let late_bound_regions = sig.bound_vars().into_iter().filter_map(|var| match var {
+        ty::BoundVariableKind::Region(ty::BrNamed(_, name)) if name != kw::UnderscoreLifetime => {
+            Some(clean::GenericParamDef::lifetime(name))
+        }
+        _ => None,
+    });
+
+    let predicates = cx.tcx.explicit_predicates_of(did);
     let (generics, decl) = clean::enter_impl_trait(cx, |cx| {
         // NOTE: generics need to be cleaned before the decl!
-        let generics = clean_ty_generics(cx, cx.tcx.generics_of(did), predicates);
+        let mut generics = clean_ty_generics(cx, cx.tcx.generics_of(did), predicates);
+        // FIXME: This does not place parameters in source order (late-bound ones come last)
+        generics.params.extend(late_bound_regions);
         let decl = clean_fn_decl_from_did_and_sig(cx, Some(did), sig);
         (generics, decl)
     });
@@ -296,6 +317,21 @@ pub(crate) fn build_impls(
     for &did in tcx.inherent_impls(did).iter() {
         build_impl(cx, parent_module, did, attrs, ret);
     }
+
+    // This pretty much exists expressly for `dyn Error` traits that exist in the `alloc` crate.
+    // See also:
+    //
+    // * https://github.com/rust-lang/rust/issues/103170 — where it didn't used to get documented
+    // * https://github.com/rust-lang/rust/pull/99917 — where the feature got used
+    // * https://github.com/rust-lang/rust/issues/53487 — overall tracking issue for Error
+    if tcx.has_attr(did, sym::rustc_has_incoherent_inherent_impls) {
+        use rustc_middle::ty::fast_reject::SimplifiedTypeGen::*;
+        let type_ =
+            if tcx.is_trait(did) { TraitSimplifiedType(did) } else { AdtSimplifiedType(did) };
+        for &did in tcx.incoherent_impls(type_) {
+            build_impl(cx, parent_module, did, attrs, ret);
+        }
+    }
 }
 
 /// `parent_module` refers to the parent of the re-export, not the original item
@@ -347,7 +383,7 @@ pub(crate) fn build_impl(
     if !did.is_local() {
         if let Some(traitref) = associated_trait {
             let did = traitref.def_id;
-            if !cx.cache.access_levels.is_public(did) {
+            if !cx.cache.effective_visibilities.is_directly_public(tcx, did) {
                 return;
             }
 
@@ -376,7 +412,7 @@ pub(crate) fn build_impl(
     // reachable in rustdoc generated documentation
     if !did.is_local() {
         if let Some(did) = for_.def_id(&cx.cache) {
-            if !cx.cache.access_levels.is_public(did) {
+            if !cx.cache.effective_visibilities.is_directly_public(tcx, did) {
                 return;
             }
 
@@ -517,7 +553,6 @@ pub(crate) fn build_impl(
             },
         })),
         Box::new(merged_attrs),
-        cx,
         cfg,
     ));
 }
@@ -565,13 +600,12 @@ fn build_module_items(
                     name: None,
                     attrs: Box::new(clean::Attributes::default()),
                     item_id: ItemId::Primitive(prim_ty, did.krate),
-                    visibility: clean::Public,
                     kind: Box::new(clean::ImportItem(clean::Import::new_simple(
                         item.ident.name,
                         clean::ImportSource {
                             path: clean::Path {
                                 res,
-                                segments: vec![clean::PathSegment {
+                                segments: thin_vec![clean::PathSegment {
                                     name: prim_ty.as_sym(),
                                     args: clean::GenericArgs::AngleBracketed {
                                         args: Default::default(),
@@ -584,6 +618,7 @@ fn build_module_items(
                         true,
                     ))),
                     cfg: None,
+                    inline_stmt_id: None,
                 });
             } else if let Some(i) = try_inline(cx, did, None, res, item.ident.name, None, visited) {
                 items.extend(i)
@@ -627,7 +662,7 @@ fn build_macro(
     match CStore::from_tcx(cx.tcx).load_macro_untracked(def_id, cx.sess()) {
         LoadedMacro::MacroDef(item_def, _) => {
             if let ast::ItemKind::MacroDef(ref def) = item_def.kind {
-                let vis = clean_visibility(cx.tcx.visibility(import_def_id.unwrap_or(def_id)));
+                let vis = cx.tcx.visibility(import_def_id.unwrap_or(def_id));
                 clean::MacroItem(clean::Macro {
                     source: utils::display_macro_source(cx, name, def, def_id, vis),
                 })
diff --git a/src/librustdoc/clean/mod.rs b/src/librustdoc/clean/mod.rs
index d86a26826416..c2f78fd5950f 100644
--- a/src/librustdoc/clean/mod.rs
+++ b/src/librustdoc/clean/mod.rs
@@ -12,7 +12,7 @@ pub(crate) mod utils;
 
 use rustc_ast as ast;
 use rustc_attr as attr;
-use rustc_data_structures::fx::{FxHashMap, FxHashSet};
+use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexSet};
 use rustc_hir as hir;
 use rustc_hir::def::{CtorKind, DefKind, Res};
 use rustc_hir::def_id::{DefId, LOCAL_CRATE};
@@ -74,12 +74,12 @@ pub(crate) fn clean_doc_module<'tcx>(doc: &DocModule<'tcx>, cx: &mut DocContext<
     // This covers the case where somebody does an import which should pull in an item,
     // but there's already an item with the same namespace and same name. Rust gives
     // priority to the not-imported one, so we should, too.
-    items.extend(doc.items.iter().flat_map(|(item, renamed)| {
+    items.extend(doc.items.iter().flat_map(|(item, renamed, import_id)| {
         // First, lower everything other than imports.
         if matches!(item.kind, hir::ItemKind::Use(_, hir::UseKind::Glob)) {
             return Vec::new();
         }
-        let v = clean_maybe_renamed_item(cx, item, *renamed);
+        let v = clean_maybe_renamed_item(cx, item, *renamed, *import_id);
         for item in &v {
             if let Some(name) = item.name && !item.attrs.lists(sym::doc).has_word(sym::hidden) {
                 inserted.insert((item.type_(), name));
@@ -87,7 +87,7 @@ pub(crate) fn clean_doc_module<'tcx>(doc: &DocModule<'tcx>, cx: &mut DocContext<
         }
         v
     }));
-    items.extend(doc.items.iter().flat_map(|(item, renamed)| {
+    items.extend(doc.items.iter().flat_map(|(item, renamed, _)| {
         // Now we actually lower the imports, skipping everything else.
         if let hir::ItemKind::Use(path, hir::UseKind::Glob) = item.kind {
             let name = renamed.unwrap_or_else(|| cx.tcx.hir().name(item.hir_id()));
@@ -182,10 +182,9 @@ fn clean_poly_trait_ref_with_bindings<'tcx>(
         .collect_referenced_late_bound_regions(&poly_trait_ref)
         .into_iter()
         .filter_map(|br| match br {
-            ty::BrNamed(_, name) if name != kw::UnderscoreLifetime => Some(GenericParamDef {
-                name,
-                kind: GenericParamDefKind::Lifetime { outlives: vec![] },
-            }),
+            ty::BrNamed(_, name) if name != kw::UnderscoreLifetime => {
+                Some(GenericParamDef::lifetime(name))
+            }
             _ => None,
         })
         .collect();
@@ -227,7 +226,7 @@ pub(crate) fn clean_middle_const<'tcx>(
     // FIXME: instead of storing the stringified expression, store `self` directly instead.
     Constant {
         type_: clean_middle_ty(constant.ty(), cx, None),
-        kind: ConstantKind::TyConst { expr: constant.to_string() },
+        kind: ConstantKind::TyConst { expr: constant.to_string().into() },
     }
 }
 
@@ -415,6 +414,16 @@ fn clean_projection<'tcx>(
     cx: &mut DocContext<'tcx>,
     def_id: Option<DefId>,
 ) -> Type {
+    if cx.tcx.def_kind(ty.item_def_id) == DefKind::ImplTraitPlaceholder {
+        let bounds = cx
+            .tcx
+            .explicit_item_bounds(ty.item_def_id)
+            .iter()
+            .map(|(bound, _)| EarlyBinder(*bound).subst(cx.tcx, ty.substs))
+            .collect::<Vec<_>>();
+        return clean_middle_opaque_bounds(cx, bounds);
+    }
+
     let trait_ = clean_trait_ref_with_bindings(cx, ty.trait_ref(cx.tcx), ThinVec::new());
     let self_type = clean_middle_ty(ty.self_ty(), cx, None);
     let self_def_id = if let Some(def_id) = def_id {
@@ -591,7 +600,7 @@ pub(crate) fn clean_generics<'tcx>(
         })
         .collect::<Vec<_>>();
 
-    let mut params = Vec::with_capacity(gens.params.len());
+    let mut params = ThinVec::with_capacity(gens.params.len());
     for p in gens.params.iter().filter(|p| !is_impl_trait(p) && !is_elided_lifetime(p)) {
         let p = clean_generic_param(cx, Some(gens), p);
         params.push(p);
@@ -665,7 +674,7 @@ fn clean_ty_generics<'tcx>(
             }
             ty::GenericParamDefKind::Const { .. } => Some(clean_generic_param_def(param, cx)),
         })
-        .collect::<Vec<GenericParamDef>>();
+        .collect::<ThinVec<GenericParamDef>>();
 
     // param index -> [(trait DefId, associated type name & generics, type, higher-ranked params)]
     let mut impl_trait_proj =
@@ -731,10 +740,7 @@ fn clean_ty_generics<'tcx>(
                             p.get_bound_params()
                                 .into_iter()
                                 .flatten()
-                                .map(|param| GenericParamDef {
-                                    name: param.0,
-                                    kind: GenericParamDefKind::Lifetime { outlives: Vec::new() },
-                                })
+                                .map(|param| GenericParamDef::lifetime(param.0))
                                 .collect(),
                         ));
                     }
@@ -870,7 +876,7 @@ fn clean_fn_or_proc_macro<'tcx>(
             ProcMacroItem(ProcMacro { kind, helpers })
         }
         None => {
-            let mut func = clean_function(cx, sig, generics, body_id);
+            let mut func = clean_function(cx, sig, generics, FunctionArgs::Body(body_id));
             clean_fn_decl_legacy_const_generics(&mut func, attrs);
             FunctionItem(func)
         }
@@ -907,16 +913,28 @@ fn clean_fn_decl_legacy_const_generics(func: &mut Function, attrs: &[ast::Attrib
     }
 }
 
+enum FunctionArgs<'tcx> {
+    Body(hir::BodyId),
+    Names(&'tcx [Ident]),
+}
+
 fn clean_function<'tcx>(
     cx: &mut DocContext<'tcx>,
     sig: &hir::FnSig<'tcx>,
     generics: &hir::Generics<'tcx>,
-    body_id: hir::BodyId,
+    args: FunctionArgs<'tcx>,
 ) -> Box<Function> {
     let (generics, decl) = enter_impl_trait(cx, |cx| {
         // NOTE: generics must be cleaned before args
         let generics = clean_generics(generics, cx);
-        let args = clean_args_from_types_and_body_id(cx, sig.decl.inputs, body_id);
+        let args = match args {
+            FunctionArgs::Body(body_id) => {
+                clean_args_from_types_and_body_id(cx, sig.decl.inputs, body_id)
+            }
+            FunctionArgs::Names(names) => {
+                clean_args_from_types_and_names(cx, sig.decl.inputs, names)
+            }
+        };
         let mut decl = clean_fn_decl_with_args(cx, sig.decl, args);
         if sig.header.is_async() {
             decl.output = decl.sugared_async_return_type();
@@ -935,12 +953,14 @@ fn clean_args_from_types_and_names<'tcx>(
         values: types
             .iter()
             .enumerate()
-            .map(|(i, ty)| {
-                let mut name = names.get(i).map_or(kw::Empty, |ident| ident.name);
-                if name.is_empty() {
-                    name = kw::Underscore;
-                }
-                Argument { name, type_: clean_ty(ty, cx), is_const: false }
+            .map(|(i, ty)| Argument {
+                type_: clean_ty(ty, cx),
+                name: names
+                    .get(i)
+                    .map(|ident| ident.name)
+                    .filter(|ident| !ident.is_empty())
+                    .unwrap_or(kw::Underscore),
+                is_const: false,
             })
             .collect(),
     }
@@ -1002,7 +1022,11 @@ fn clean_fn_decl_from_did_and_sig<'tcx>(
                 .iter()
                 .map(|t| Argument {
                     type_: clean_middle_ty(*t, cx, None),
-                    name: names.next().map_or(kw::Empty, |i| i.name),
+                    name: names
+                        .next()
+                        .map(|i| i.name)
+                        .filter(|i| !i.is_empty())
+                        .unwrap_or(kw::Underscore),
                     is_const: false,
                 })
                 .collect(),
@@ -1032,7 +1056,7 @@ fn clean_poly_trait_ref<'tcx>(
 }
 
 fn clean_trait_item<'tcx>(trait_item: &hir::TraitItem<'tcx>, cx: &mut DocContext<'tcx>) -> Item {
-    let local_did = trait_item.def_id.to_def_id();
+    let local_did = trait_item.owner_id.to_def_id();
     cx.with_param_env(local_did, |cx| {
         let inner = match trait_item.kind {
             hir::TraitItemKind::Const(ty, Some(default)) => AssocConstItem(
@@ -1041,18 +1065,12 @@ fn clean_trait_item<'tcx>(trait_item: &hir::TraitItem<'tcx>, cx: &mut DocContext
             ),
             hir::TraitItemKind::Const(ty, None) => TyAssocConstItem(clean_ty(ty, cx)),
             hir::TraitItemKind::Fn(ref sig, hir::TraitFn::Provided(body)) => {
-                let m = clean_function(cx, sig, trait_item.generics, body);
+                let m = clean_function(cx, sig, trait_item.generics, FunctionArgs::Body(body));
                 MethodItem(m, None)
             }
             hir::TraitItemKind::Fn(ref sig, hir::TraitFn::Required(names)) => {
-                let (generics, decl) = enter_impl_trait(cx, |cx| {
-                    // NOTE: generics must be cleaned before args
-                    let generics = clean_generics(trait_item.generics, cx);
-                    let args = clean_args_from_types_and_names(cx, sig.decl.inputs, names);
-                    let decl = clean_fn_decl_with_args(cx, sig.decl, args);
-                    (generics, decl)
-                });
-                TyMethodItem(Box::new(Function { decl, generics }))
+                let m = clean_function(cx, sig, trait_item.generics, FunctionArgs::Names(names));
+                TyMethodItem(m)
             }
             hir::TraitItemKind::Type(bounds, Some(default)) => {
                 let generics = enter_impl_trait(cx, |cx| clean_generics(trait_item.generics, cx));
@@ -1070,13 +1088,10 @@ fn clean_trait_item<'tcx>(trait_item: &hir::TraitItem<'tcx>, cx: &mut DocContext
             hir::TraitItemKind::Type(bounds, None) => {
                 let generics = enter_impl_trait(cx, |cx| clean_generics(trait_item.generics, cx));
                 let bounds = bounds.iter().filter_map(|x| clean_generic_bound(x, cx)).collect();
-                TyAssocTypeItem(Box::new(generics), bounds)
+                TyAssocTypeItem(generics, bounds)
             }
         };
-        let what_rustc_thinks =
-            Item::from_def_id_and_parts(local_did, Some(trait_item.ident.name), inner, cx);
-        // Trait items always inherit the trait's visibility -- we don't want to show `pub`.
-        Item { visibility: Inherited, ..what_rustc_thinks }
+        Item::from_def_id_and_parts(local_did, Some(trait_item.ident.name), inner, cx)
     })
 }
 
@@ -1084,7 +1099,7 @@ pub(crate) fn clean_impl_item<'tcx>(
     impl_: &hir::ImplItem<'tcx>,
     cx: &mut DocContext<'tcx>,
 ) -> Item {
-    let local_did = impl_.def_id.to_def_id();
+    let local_did = impl_.owner_id.to_def_id();
     cx.with_param_env(local_did, |cx| {
         let inner = match impl_.kind {
             hir::ImplItemKind::Const(ty, expr) => {
@@ -1092,8 +1107,8 @@ pub(crate) fn clean_impl_item<'tcx>(
                 AssocConstItem(clean_ty(ty, cx), default)
             }
             hir::ImplItemKind::Fn(ref sig, body) => {
-                let m = clean_function(cx, sig, impl_.generics, body);
-                let defaultness = cx.tcx.impl_defaultness(impl_.def_id);
+                let m = clean_function(cx, sig, impl_.generics, FunctionArgs::Body(body));
+                let defaultness = cx.tcx.impl_defaultness(impl_.owner_id);
                 MethodItem(m, Some(defaultness))
             }
             hir::ImplItemKind::Type(hir_ty) => {
@@ -1107,18 +1122,7 @@ pub(crate) fn clean_impl_item<'tcx>(
             }
         };
 
-        let mut what_rustc_thinks =
-            Item::from_def_id_and_parts(local_did, Some(impl_.ident.name), inner, cx);
-
-        let impl_ref = cx.tcx.impl_trait_ref(cx.tcx.local_parent(impl_.def_id.def_id));
-
-        // Trait impl items always inherit the impl's visibility --
-        // we don't want to show `pub`.
-        if impl_ref.is_some() {
-            what_rustc_thinks.visibility = Inherited;
-        }
-
-        what_rustc_thinks
+        Item::from_def_id_and_parts(local_did, Some(impl_.ident.name), inner, cx)
     })
 }
 
@@ -1142,12 +1146,25 @@ pub(crate) fn clean_middle_assoc_item<'tcx>(
             }
         }
         ty::AssocKind::Fn => {
-            let generics = clean_ty_generics(
+            let sig = tcx.fn_sig(assoc_item.def_id);
+
+            let late_bound_regions = sig.bound_vars().into_iter().filter_map(|var| match var {
+                ty::BoundVariableKind::Region(ty::BrNamed(_, name))
+                    if name != kw::UnderscoreLifetime =>
+                {
+                    Some(GenericParamDef::lifetime(name))
+                }
+                _ => None,
+            });
+
+            let mut generics = clean_ty_generics(
                 cx,
                 tcx.generics_of(assoc_item.def_id),
                 tcx.explicit_predicates_of(assoc_item.def_id),
             );
-            let sig = tcx.fn_sig(assoc_item.def_id);
+            // FIXME: This does not place parameters in source order (late-bound ones come last)
+            generics.params.extend(late_bound_regions);
+
             let mut decl = clean_fn_decl_from_did_and_sig(cx, Some(assoc_item.def_id), sig);
 
             if assoc_item.fn_has_self_parameter {
@@ -1198,7 +1215,7 @@ pub(crate) fn clean_middle_assoc_item<'tcx>(
                         true
                     }
                     (GenericParamDefKind::Const { .. }, GenericArg::Const(c)) => match &c.kind {
-                        ConstantKind::TyConst { expr } => expr == param.name.as_str(),
+                        ConstantKind::TyConst { expr } => **expr == *param.name.as_str(),
                         _ => false,
                     },
                     _ => false,
@@ -1215,56 +1232,47 @@ pub(crate) fn clean_middle_assoc_item<'tcx>(
                     tcx.generics_of(assoc_item.def_id),
                     ty::GenericPredicates { parent: None, predicates },
                 );
-                // Move bounds that are (likely) directly attached to the associated type
-                // from the where clause to the associated type.
-                // There is no guarantee that this is what the user actually wrote but we have
-                // no way of knowing.
-                let mut bounds = generics
-                    .where_predicates
-                    .drain_filter(|pred| match *pred {
-                        WherePredicate::BoundPredicate {
-                            ty: QPath(box QPathData { ref assoc, ref self_type, ref trait_, .. }),
-                            ..
-                        } => {
-                            if assoc.name != my_name {
-                                return false;
-                            }
-                            if trait_.def_id() != assoc_item.container_id(tcx) {
-                                return false;
-                            }
-                            match *self_type {
-                                Generic(ref s) if *s == kw::SelfUpper => {}
-                                _ => return false,
-                            }
-                            match &assoc.args {
-                                GenericArgs::AngleBracketed { args, bindings } => {
-                                    if !bindings.is_empty()
-                                        || generics
-                                            .params
-                                            .iter()
-                                            .zip(args.iter())
-                                            .any(|(param, arg)| !param_eq_arg(param, arg))
-                                    {
-                                        return false;
-                                    }
-                                }
-                                GenericArgs::Parenthesized { .. } => {
-                                    // The only time this happens is if we're inside the rustdoc for Fn(),
-                                    // which only has one associated type, which is not a GAT, so whatever.
+                // Filter out the bounds that are (likely?) directly attached to the associated type,
+                // as opposed to being located in the where clause.
+                let mut bounds: Vec<GenericBound> = Vec::new();
+                generics.where_predicates.retain_mut(|pred| match *pred {
+                    WherePredicate::BoundPredicate {
+                        ty: QPath(box QPathData { ref assoc, ref self_type, ref trait_, .. }),
+                        bounds: ref mut pred_bounds,
+                        ..
+                    } => {
+                        if assoc.name != my_name {
+                            return true;
+                        }
+                        if trait_.def_id() != assoc_item.container_id(tcx) {
+                            return true;
+                        }
+                        match *self_type {
+                            Generic(ref s) if *s == kw::SelfUpper => {}
+                            _ => return true,
+                        }
+                        match &assoc.args {
+                            GenericArgs::AngleBracketed { args, bindings } => {
+                                if !bindings.is_empty()
+                                    || generics
+                                        .params
+                                        .iter()
+                                        .zip(args.iter())
+                                        .any(|(param, arg)| !param_eq_arg(param, arg))
+                                {
+                                    return true;
                                 }
                             }
-                            true
+                            GenericArgs::Parenthesized { .. } => {
+                                // The only time this happens is if we're inside the rustdoc for Fn(),
+                                // which only has one associated type, which is not a GAT, so whatever.
+                            }
                         }
-                        _ => false,
-                    })
-                    .flat_map(|pred| {
-                        if let WherePredicate::BoundPredicate { bounds, .. } = pred {
-                            bounds
-                        } else {
-                            unreachable!()
-                        }
-                    })
-                    .collect::<Vec<_>>();
+                        bounds.extend(mem::replace(pred_bounds, Vec::new()));
+                        false
+                    }
+                    _ => true,
+                });
                 // Our Sized/?Sized bound didn't get handled when creating the generics
                 // because we didn't actually get our whole set of bounds until just now
                 // (some of them may have come from the trait). If we do have a sized
@@ -1280,7 +1288,7 @@ pub(crate) fn clean_middle_assoc_item<'tcx>(
                 // (generic) associated type from the where clause to the respective parameter.
                 // There is no guarantee that this is what the user actually wrote but we have
                 // no way of knowing.
-                let mut where_predicates = Vec::new();
+                let mut where_predicates = ThinVec::new();
                 for mut pred in generics.where_predicates {
                     if let WherePredicate::BoundPredicate { ty: Generic(arg), bounds, .. } = &mut pred
                     && let Some(GenericParamDef {
@@ -1288,7 +1296,16 @@ pub(crate) fn clean_middle_assoc_item<'tcx>(
                         ..
                     }) = generics.params.iter_mut().find(|param| &param.name == arg)
                     {
-                        param_bounds.extend(mem::take(bounds));
+                        param_bounds.append(bounds);
+                    } else if let WherePredicate::RegionPredicate { lifetime: Lifetime(arg), bounds } = &mut pred
+                    && let Some(GenericParamDef {
+                        kind: GenericParamDefKind::Lifetime { outlives: param_bounds },
+                        ..
+                    }) = generics.params.iter_mut().find(|param| &param.name == arg) {
+                        param_bounds.extend(bounds.drain(..).map(|bound| match bound {
+                            GenericBound::Outlives(lifetime) => lifetime,
+                            _ => unreachable!(),
+                        }));
                     } else {
                         where_predicates.push(pred);
                     }
@@ -1310,7 +1327,7 @@ pub(crate) fn clean_middle_assoc_item<'tcx>(
                         bounds,
                     )
                 } else {
-                    TyAssocTypeItem(Box::new(generics), bounds)
+                    TyAssocTypeItem(generics, bounds)
                 }
             } else {
                 // FIXME: when could this happen? Associated items in inherent impls?
@@ -1321,7 +1338,10 @@ pub(crate) fn clean_middle_assoc_item<'tcx>(
                             cx,
                             Some(assoc_item.def_id),
                         ),
-                        generics: Generics { params: Vec::new(), where_predicates: Vec::new() },
+                        generics: Generics {
+                            params: ThinVec::new(),
+                            where_predicates: ThinVec::new(),
+                        },
                         item_type: None,
                     }),
                     Vec::new(),
@@ -1330,18 +1350,7 @@ pub(crate) fn clean_middle_assoc_item<'tcx>(
         }
     };
 
-    let mut what_rustc_thinks =
-        Item::from_def_id_and_parts(assoc_item.def_id, Some(assoc_item.name), kind, cx);
-
-    let impl_ref = tcx.impl_trait_ref(tcx.parent(assoc_item.def_id));
-
-    // Trait impl items always inherit the impl's visibility --
-    // we don't want to show `pub`.
-    if impl_ref.is_some() {
-        what_rustc_thinks.visibility = Visibility::Inherited;
-    }
-
-    what_rustc_thinks
+    Item::from_def_id_and_parts(assoc_item.def_id, Some(assoc_item.name), kind, cx)
 }
 
 fn clean_qpath<'tcx>(hir_ty: &hir::Ty<'tcx>, cx: &mut DocContext<'tcx>) -> Type {
@@ -1396,7 +1405,8 @@ fn clean_qpath<'tcx>(hir_ty: &hir::Ty<'tcx>, cx: &mut DocContext<'tcx>) -> Type
                 ty::Projection(proj) => Res::Def(DefKind::Trait, proj.trait_ref(cx.tcx).def_id),
                 // Rustdoc handles `ty::Error`s by turning them into `Type::Infer`s.
                 ty::Error(_) => return Type::Infer,
-                _ => bug!("clean: expected associated type, found `{:?}`", ty),
+                // Otherwise, this is an inherent associated type.
+                _ => return clean_middle_ty(ty, cx, None),
             };
             let trait_ = clean_path(&hir::Path { span, res, segments: &[] }, cx);
             register_res(cx, trait_.res);
@@ -1421,7 +1431,7 @@ fn maybe_expand_private_type_alias<'tcx>(
     let Res::Def(DefKind::TyAlias, def_id) = path.res else { return None };
     // Substitute private type aliases
     let def_id = def_id.as_local()?;
-    let alias = if !cx.cache.access_levels.is_exported(def_id.to_def_id()) {
+    let alias = if !cx.cache.effective_visibilities.is_exported(cx.tcx, def_id.to_def_id()) {
         &cx.tcx.hir().expect_item(def_id).kind
     } else {
         return None;
@@ -1544,7 +1554,7 @@ pub(crate) fn clean_ty<'tcx>(ty: &hir::Ty<'tcx>, cx: &mut DocContext<'tcx>) -> T
                 }
             };
 
-            Array(Box::new(clean_ty(ty, cx)), length)
+            Array(Box::new(clean_ty(ty, cx)), length.into())
         }
         TyKind::Tup(tys) => Tuple(tys.iter().map(|ty| clean_ty(ty, cx)).collect()),
         TyKind::OpaqueDef(item_id, _, _) => {
@@ -1616,7 +1626,7 @@ pub(crate) fn clean_middle_ty<'tcx>(
         ty::Array(ty, mut n) => {
             n = n.eval(cx.tcx, ty::ParamEnv::reveal_all());
             let n = print_const(cx, n);
-            Array(Box::new(clean_middle_ty(ty, cx, None)), n)
+            Array(Box::new(clean_middle_ty(ty, cx, None)), n.into())
         }
         ty::RawPtr(mt) => RawPointer(mt.mutbl, Box::new(clean_middle_ty(mt.ty, cx, None))),
         ty::Ref(r, ty, mutbl) => BorrowedRef {
@@ -1667,6 +1677,9 @@ pub(crate) fn clean_middle_ty<'tcx>(
 
             inline::record_extern_fqn(cx, did, ItemType::Trait);
 
+            // FIXME(fmease): Hide the trait-object lifetime bound if it coincides with its default
+            // to partially address #44306. Follow the rules outlined at
+            // https://doc.rust-lang.org/reference/lifetime-elision.html#default-trait-object-lifetimes
             let lifetime = clean_middle_region(*reg);
             let mut bounds = dids
                 .map(|did| {
@@ -1694,8 +1707,22 @@ pub(crate) fn clean_middle_ty<'tcx>(
                 })
                 .collect();
 
+            let late_bound_regions: FxIndexSet<_> = obj
+                .iter()
+                .flat_map(|pb| pb.bound_vars())
+                .filter_map(|br| match br {
+                    ty::BoundVariableKind::Region(ty::BrNamed(_, name))
+                        if name != kw::UnderscoreLifetime =>
+                    {
+                        Some(GenericParamDef::lifetime(name))
+                    }
+                    _ => None,
+                })
+                .collect();
+            let late_bound_regions = late_bound_regions.into_iter().collect();
+
             let path = external_path(cx, did, false, bindings, substs);
-            bounds.insert(0, PolyTrait { trait_: path, generic_params: Vec::new() });
+            bounds.insert(0, PolyTrait { trait_: path, generic_params: late_bound_regions });
 
             DynTrait(bounds, lifetime)
         }
@@ -1720,59 +1747,7 @@ pub(crate) fn clean_middle_ty<'tcx>(
                 .iter()
                 .map(|(bound, _)| EarlyBinder(*bound).subst(cx.tcx, substs))
                 .collect::<Vec<_>>();
-            let mut regions = vec![];
-            let mut has_sized = false;
-            let mut bounds = bounds
-                .iter()
-                .filter_map(|bound| {
-                    let bound_predicate = bound.kind();
-                    let trait_ref = match bound_predicate.skip_binder() {
-                        ty::PredicateKind::Trait(tr) => bound_predicate.rebind(tr.trait_ref),
-                        ty::PredicateKind::TypeOutlives(ty::OutlivesPredicate(_ty, reg)) => {
-                            if let Some(r) = clean_middle_region(reg) {
-                                regions.push(GenericBound::Outlives(r));
-                            }
-                            return None;
-                        }
-                        _ => return None,
-                    };
-
-                    if let Some(sized) = cx.tcx.lang_items().sized_trait() {
-                        if trait_ref.def_id() == sized {
-                            has_sized = true;
-                            return None;
-                        }
-                    }
-
-                    let bindings: ThinVec<_> = bounds
-                        .iter()
-                        .filter_map(|bound| {
-                            if let ty::PredicateKind::Projection(proj) = bound.kind().skip_binder()
-                            {
-                                if proj.projection_ty.trait_ref(cx.tcx) == trait_ref.skip_binder() {
-                                    Some(TypeBinding {
-                                        assoc: projection_to_path_segment(proj.projection_ty, cx),
-                                        kind: TypeBindingKind::Equality {
-                                            term: clean_middle_term(proj.term, cx),
-                                        },
-                                    })
-                                } else {
-                                    None
-                                }
-                            } else {
-                                None
-                            }
-                        })
-                        .collect();
-
-                    Some(clean_poly_trait_ref_with_bindings(cx, trait_ref, bindings))
-                })
-                .collect::<Vec<_>>();
-            bounds.extend(regions);
-            if !has_sized && !bounds.is_empty() {
-                bounds.insert(0, GenericBound::maybe_sized(cx));
-            }
-            ImplTrait(bounds)
+            clean_middle_opaque_bounds(cx, bounds)
         }
 
         ty::Closure(..) => panic!("Closure"),
@@ -1785,6 +1760,64 @@ pub(crate) fn clean_middle_ty<'tcx>(
     }
 }
 
+fn clean_middle_opaque_bounds<'tcx>(
+    cx: &mut DocContext<'tcx>,
+    bounds: Vec<ty::Predicate<'tcx>>,
+) -> Type {
+    let mut regions = vec![];
+    let mut has_sized = false;
+    let mut bounds = bounds
+        .iter()
+        .filter_map(|bound| {
+            let bound_predicate = bound.kind();
+            let trait_ref = match bound_predicate.skip_binder() {
+                ty::PredicateKind::Trait(tr) => bound_predicate.rebind(tr.trait_ref),
+                ty::PredicateKind::TypeOutlives(ty::OutlivesPredicate(_ty, reg)) => {
+                    if let Some(r) = clean_middle_region(reg) {
+                        regions.push(GenericBound::Outlives(r));
+                    }
+                    return None;
+                }
+                _ => return None,
+            };
+
+            if let Some(sized) = cx.tcx.lang_items().sized_trait() {
+                if trait_ref.def_id() == sized {
+                    has_sized = true;
+                    return None;
+                }
+            }
+
+            let bindings: ThinVec<_> = bounds
+                .iter()
+                .filter_map(|bound| {
+                    if let ty::PredicateKind::Projection(proj) = bound.kind().skip_binder() {
+                        if proj.projection_ty.trait_ref(cx.tcx) == trait_ref.skip_binder() {
+                            Some(TypeBinding {
+                                assoc: projection_to_path_segment(proj.projection_ty, cx),
+                                kind: TypeBindingKind::Equality {
+                                    term: clean_middle_term(proj.term, cx),
+                                },
+                            })
+                        } else {
+                            None
+                        }
+                    } else {
+                        None
+                    }
+                })
+                .collect();
+
+            Some(clean_poly_trait_ref_with_bindings(cx, trait_ref, bindings))
+        })
+        .collect::<Vec<_>>();
+    bounds.extend(regions);
+    if !has_sized && !bounds.is_empty() {
+        bounds.insert(0, GenericBound::maybe_sized(cx));
+    }
+    ImplTrait(bounds)
+}
+
 pub(crate) fn clean_field<'tcx>(field: &hir::FieldDef<'tcx>, cx: &mut DocContext<'tcx>) -> Item {
     let def_id = cx.tcx.hir().local_def_id(field.hir_id).to_def_id();
     clean_field_with_def_id(def_id, field.ident.name, clean_ty(field.ty, cx), cx)
@@ -1805,30 +1838,7 @@ pub(crate) fn clean_field_with_def_id(
     ty: Type,
     cx: &mut DocContext<'_>,
 ) -> Item {
-    let what_rustc_thinks =
-        Item::from_def_id_and_parts(def_id, Some(name), StructFieldItem(ty), cx);
-    if is_field_vis_inherited(cx.tcx, def_id) {
-        // Variant fields inherit their enum's visibility.
-        Item { visibility: Visibility::Inherited, ..what_rustc_thinks }
-    } else {
-        what_rustc_thinks
-    }
-}
-
-fn is_field_vis_inherited(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
-    let parent = tcx.parent(def_id);
-    match tcx.def_kind(parent) {
-        DefKind::Struct | DefKind::Union => false,
-        DefKind::Variant => true,
-        parent_kind => panic!("unexpected parent kind: {:?}", parent_kind),
-    }
-}
-
-pub(crate) fn clean_visibility(vis: ty::Visibility<DefId>) -> Visibility {
-    match vis {
-        ty::Visibility::Public => Visibility::Public,
-        ty::Visibility::Restricted(module) => Visibility::Restricted(module),
-    }
+    Item::from_def_id_and_parts(def_id, Some(name), StructFieldItem(ty), cx)
 }
 
 pub(crate) fn clean_variant_def<'tcx>(variant: &ty::VariantDef, cx: &mut DocContext<'tcx>) -> Item {
@@ -1845,10 +1855,7 @@ pub(crate) fn clean_variant_def<'tcx>(variant: &ty::VariantDef, cx: &mut DocCont
             fields: variant.fields.iter().map(|field| clean_middle_field(field, cx)).collect(),
         }),
     };
-    let what_rustc_thinks =
-        Item::from_def_id_and_parts(variant.def_id, Some(variant.name), VariantItem(kind), cx);
-    // don't show `pub` for variants, which always inherit visibility
-    Item { visibility: Inherited, ..what_rustc_thinks }
+    Item::from_def_id_and_parts(variant.def_id, Some(variant.name), VariantItem(kind), cx)
 }
 
 fn clean_variant_data<'tcx>(
@@ -1935,14 +1942,88 @@ fn clean_bare_fn_ty<'tcx>(
     BareFunctionDecl { unsafety: bare_fn.unsafety, abi: bare_fn.abi, decl, generic_params }
 }
 
+/// This visitor is used to go through only the "top level" of a item and not enter any sub
+/// item while looking for a given `Ident` which is stored into `item` if found.
+struct OneLevelVisitor<'hir> {
+    map: rustc_middle::hir::map::Map<'hir>,
+    item: Option<&'hir hir::Item<'hir>>,
+    looking_for: Ident,
+    target_hir_id: hir::HirId,
+}
+
+impl<'hir> OneLevelVisitor<'hir> {
+    fn new(map: rustc_middle::hir::map::Map<'hir>, target_hir_id: hir::HirId) -> Self {
+        Self { map, item: None, looking_for: Ident::empty(), target_hir_id }
+    }
+
+    fn reset(&mut self, looking_for: Ident) {
+        self.looking_for = looking_for;
+        self.item = None;
+    }
+}
+
+impl<'hir> hir::intravisit::Visitor<'hir> for OneLevelVisitor<'hir> {
+    type NestedFilter = rustc_middle::hir::nested_filter::All;
+
+    fn nested_visit_map(&mut self) -> Self::Map {
+        self.map
+    }
+
+    fn visit_item(&mut self, item: &'hir hir::Item<'hir>) {
+        if self.item.is_none()
+            && item.ident == self.looking_for
+            && matches!(item.kind, hir::ItemKind::Use(_, _))
+            || item.hir_id() == self.target_hir_id
+        {
+            self.item = Some(item);
+        }
+    }
+}
+
+/// Because a `Use` item directly links to the imported item, we need to manually go through each
+/// import one by one. To do so, we go to the parent item and look for the `Ident` into it. Then,
+/// if we found the "end item" (the imported one), we stop there because we don't need its
+/// documentation. Otherwise, we repeat the same operation until we find the "end item".
+fn get_all_import_attributes<'hir>(
+    mut item: &hir::Item<'hir>,
+    tcx: TyCtxt<'hir>,
+    target_hir_id: hir::HirId,
+    attributes: &mut Vec<ast::Attribute>,
+) {
+    let hir_map = tcx.hir();
+    let mut visitor = OneLevelVisitor::new(hir_map, target_hir_id);
+    // If the item is an import and has at least a path with two parts, we go into it.
+    while let hir::ItemKind::Use(path, _) = item.kind &&
+        path.segments.len() > 1 &&
+        let hir::def::Res::Def(_, def_id) = path.segments[path.segments.len() - 2].res
+    {
+        if let Some(hir::Node::Item(parent_item)) = hir_map.get_if_local(def_id) {
+            // We add the attributes from this import into the list.
+            attributes.extend_from_slice(hir_map.attrs(item.hir_id()));
+            // We get the `Ident` we will be looking for into `item`.
+            let looking_for = path.segments[path.segments.len() - 1].ident;
+            visitor.reset(looking_for);
+            hir::intravisit::walk_item(&mut visitor, parent_item);
+            if let Some(i) = visitor.item {
+                item = i;
+            } else {
+                break;
+            }
+        } else {
+            break;
+        }
+    }
+}
+
 fn clean_maybe_renamed_item<'tcx>(
     cx: &mut DocContext<'tcx>,
     item: &hir::Item<'tcx>,
     renamed: Option<Symbol>,
+    import_id: Option<hir::HirId>,
 ) -> Vec<Item> {
     use hir::ItemKind;
 
-    let def_id = item.def_id.to_def_id();
+    let def_id = item.owner_id.to_def_id();
     let mut name = renamed.unwrap_or_else(|| cx.tcx.hir().name(item.hir_id()));
     cx.with_param_env(def_id, |cx| {
         let kind = match item.kind {
@@ -1989,7 +2070,7 @@ fn clean_maybe_renamed_item<'tcx>(
                 clean_fn_or_proc_macro(item, sig, generics, body_id, &mut name, cx)
             }
             ItemKind::Macro(ref macro_def, _) => {
-                let ty_vis = clean_visibility(cx.tcx.visibility(def_id));
+                let ty_vis = cx.tcx.visibility(def_id);
                 MacroItem(Macro {
                     source: display_macro_source(cx, name, macro_def, def_id, ty_vis),
                 })
@@ -2016,16 +2097,35 @@ fn clean_maybe_renamed_item<'tcx>(
             _ => unreachable!("not yet converted"),
         };
 
-        vec![Item::from_def_id_and_parts(def_id, Some(name), kind, cx)]
+        let mut extra_attrs = Vec::new();
+        if let Some(hir::Node::Item(use_node)) =
+            import_id.and_then(|hir_id| cx.tcx.hir().find(hir_id))
+        {
+            // We get all the various imports' attributes.
+            get_all_import_attributes(use_node, cx.tcx, item.hir_id(), &mut extra_attrs);
+        }
+
+        if !extra_attrs.is_empty() {
+            extra_attrs.extend_from_slice(inline::load_attrs(cx, def_id));
+            let attrs = Attributes::from_ast(&extra_attrs);
+            let cfg = extra_attrs.cfg(cx.tcx, &cx.cache.hidden_cfg);
+
+            vec![Item::from_def_id_and_attrs_and_parts(
+                def_id,
+                Some(name),
+                kind,
+                Box::new(attrs),
+                cfg,
+            )]
+        } else {
+            vec![Item::from_def_id_and_parts(def_id, Some(name), kind, cx)]
+        }
     })
 }
 
 fn clean_variant<'tcx>(variant: &hir::Variant<'tcx>, cx: &mut DocContext<'tcx>) -> Item {
     let kind = VariantItem(clean_variant_data(&variant.data, &variant.disr_expr, cx));
-    let what_rustc_thinks =
-        Item::from_hir_id_and_parts(variant.id, Some(variant.ident.name), kind, cx);
-    // don't show `pub` for variants, which are always public
-    Item { visibility: Inherited, ..what_rustc_thinks }
+    Item::from_hir_id_and_parts(variant.id, Some(variant.ident.name), kind, cx)
 }
 
 fn clean_impl<'tcx>(
@@ -2084,11 +2184,11 @@ fn clean_extern_crate<'tcx>(
     cx: &mut DocContext<'tcx>,
 ) -> Vec<Item> {
     // this is the ID of the `extern crate` statement
-    let cnum = cx.tcx.extern_mod_stmt_cnum(krate.def_id.def_id).unwrap_or(LOCAL_CRATE);
+    let cnum = cx.tcx.extern_mod_stmt_cnum(krate.owner_id.def_id).unwrap_or(LOCAL_CRATE);
     // this is the ID of the crate itself
     let crate_def_id = cnum.as_def_id();
     let attrs = cx.tcx.hir().attrs(krate.hir_id());
-    let ty_vis = cx.tcx.visibility(krate.def_id);
+    let ty_vis = cx.tcx.visibility(krate.owner_id);
     let please_inline = ty_vis.is_public()
         && attrs.iter().any(|a| {
             a.has_name(sym::doc)
@@ -2098,6 +2198,7 @@ fn clean_extern_crate<'tcx>(
                 }
         });
 
+    let krate_owner_def_id = krate.owner_id.to_def_id();
     if please_inline {
         let mut visited = FxHashSet::default();
 
@@ -2106,7 +2207,7 @@ fn clean_extern_crate<'tcx>(
         if let Some(items) = inline::try_inline(
             cx,
             cx.tcx.parent_module(krate.hir_id()).to_def_id(),
-            Some(krate.def_id.to_def_id()),
+            Some(krate_owner_def_id),
             res,
             name,
             Some(attrs),
@@ -2121,9 +2222,9 @@ fn clean_extern_crate<'tcx>(
         name: Some(name),
         attrs: Box::new(Attributes::from_ast(attrs)),
         item_id: crate_def_id.into(),
-        visibility: clean_visibility(ty_vis),
         kind: Box::new(ExternCrateItem { src: orig_name }),
         cfg: attrs.cfg(cx.tcx, &cx.cache.hidden_cfg),
+        inline_stmt_id: Some(krate_owner_def_id),
     }]
 }
 
@@ -2142,11 +2243,11 @@ fn clean_use_statement<'tcx>(
         return Vec::new();
     }
 
-    let visibility = cx.tcx.visibility(import.def_id);
+    let visibility = cx.tcx.visibility(import.owner_id);
     let attrs = cx.tcx.hir().attrs(import.hir_id());
     let inline_attr = attrs.lists(sym::doc).get_word_attr(sym::inline);
     let pub_underscore = visibility.is_public() && name == kw::Underscore;
-    let current_mod = cx.tcx.parent_module_from_def_id(import.def_id.def_id);
+    let current_mod = cx.tcx.parent_module_from_def_id(import.owner_id.def_id);
 
     // The parent of the module in which this import resides. This
     // is the same as `current_mod` if that's already the top
@@ -2217,7 +2318,7 @@ fn clean_use_statement<'tcx>(
         }
         if !denied {
             let mut visited = FxHashSet::default();
-            let import_def_id = import.def_id.to_def_id();
+            let import_def_id = import.owner_id.to_def_id();
 
             if let Some(mut items) = inline::try_inline(
                 cx,
@@ -2240,7 +2341,7 @@ fn clean_use_statement<'tcx>(
         Import::new_simple(name, resolve_use_source(cx, path), true)
     };
 
-    vec![Item::from_def_id_and_parts(import.def_id.to_def_id(), None, ImportItem(inner), cx)]
+    vec![Item::from_def_id_and_parts(import.owner_id.to_def_id(), None, ImportItem(inner), cx)]
 }
 
 fn clean_maybe_renamed_foreign_item<'tcx>(
@@ -2248,7 +2349,7 @@ fn clean_maybe_renamed_foreign_item<'tcx>(
     item: &hir::ForeignItem<'tcx>,
     renamed: Option<Symbol>,
 ) -> Item {
-    let def_id = item.def_id.to_def_id();
+    let def_id = item.owner_id.to_def_id();
     cx.with_param_env(def_id, |cx| {
         let kind = match item.kind {
             hir::ForeignItemKind::Fn(decl, names, generics) => {
diff --git a/src/librustdoc/clean/simplify.rs b/src/librustdoc/clean/simplify.rs
index 1bcb9fcd5a45..7d97d2994e46 100644
--- a/src/librustdoc/clean/simplify.rs
+++ b/src/librustdoc/clean/simplify.rs
@@ -14,13 +14,14 @@
 use rustc_data_structures::fx::FxIndexMap;
 use rustc_hir::def_id::DefId;
 use rustc_middle::ty;
+use thin_vec::ThinVec;
 
 use crate::clean;
 use crate::clean::GenericArgs as PP;
 use crate::clean::WherePredicate as WP;
 use crate::core::DocContext;
 
-pub(crate) fn where_clauses(cx: &DocContext<'_>, clauses: Vec<WP>) -> Vec<WP> {
+pub(crate) fn where_clauses(cx: &DocContext<'_>, clauses: Vec<WP>) -> ThinVec<WP> {
     // First, partition the where clause into its separate components.
     //
     // We use `FxIndexMap` so that the insertion order is preserved to prevent messing up to
@@ -50,16 +51,13 @@ pub(crate) fn where_clauses(cx: &DocContext<'_>, clauses: Vec<WP>) -> Vec<WP> {
         let Some((bounds, _)) = tybounds.get_mut(ty) else { return true };
         let bound_params = bound_params
             .into_iter()
-            .map(|param| clean::GenericParamDef {
-                name: param.0,
-                kind: clean::GenericParamDefKind::Lifetime { outlives: Vec::new() },
-            })
+            .map(|param| clean::GenericParamDef::lifetime(param.0))
             .collect();
         merge_bounds(cx, bounds, bound_params, trait_did, name, rhs)
     });
 
     // And finally, let's reassemble everything
-    let mut clauses = Vec::new();
+    let mut clauses = ThinVec::with_capacity(lifetimes.len() + tybounds.len() + equalities.len());
     clauses.extend(
         lifetimes.into_iter().map(|(lt, bounds)| WP::RegionPredicate { lifetime: lt, bounds }),
     );
@@ -98,9 +96,8 @@ pub(crate) fn merge_bounds(
         let last = trait_ref.trait_.segments.last_mut().expect("segments were empty");
 
         trait_ref.generic_params.append(&mut bound_params);
-        // Since the parameters (probably) originate from `tcx.collect_*_late_bound_regions` which
-        // returns a hash set, sort them alphabetically to guarantee a stable and deterministic
-        // output (and to fully deduplicate them).
+        // Sort parameters (likely) originating from a hashset alphabetically to
+        // produce predictable output (and to allow for full deduplication).
         trait_ref.generic_params.sort_unstable_by(|p, q| p.name.as_str().cmp(q.name.as_str()));
         trait_ref.generic_params.dedup_by_key(|p| p.name);
 
diff --git a/src/librustdoc/clean/types.rs b/src/librustdoc/clean/types.rs
index 4c130b2ffec7..3d13f7463cbb 100644
--- a/src/librustdoc/clean/types.rs
+++ b/src/librustdoc/clean/types.rs
@@ -24,7 +24,7 @@ use rustc_hir::{BodyId, Mutability};
 use rustc_hir_analysis::check::intrinsic::intrinsic_operation_unsafety;
 use rustc_index::vec::IndexVec;
 use rustc_middle::ty::fast_reject::SimplifiedType;
-use rustc_middle::ty::{self, TyCtxt};
+use rustc_middle::ty::{self, DefIdTree, TyCtxt, Visibility};
 use rustc_session::Session;
 use rustc_span::hygiene::MacroKind;
 use rustc_span::source_map::DUMMY_SP;
@@ -34,7 +34,6 @@ use rustc_target::abi::VariantIdx;
 use rustc_target::spec::abi::Abi;
 
 use crate::clean::cfg::Cfg;
-use crate::clean::clean_visibility;
 use crate::clean::external_path;
 use crate::clean::inline::{self, print_inlined_const};
 use crate::clean::utils::{is_literal_expr, print_const_expr, print_evaluated_const};
@@ -51,7 +50,6 @@ pub(crate) use self::Type::{
     Array, BareFunction, BorrowedRef, DynTrait, Generic, ImplTrait, Infer, Primitive, QPath,
     RawPointer, Slice, Tuple,
 };
-pub(crate) use self::Visibility::{Inherited, Public};
 
 #[cfg(test)]
 mod tests;
@@ -240,13 +238,13 @@ impl ExternalCrate {
                     let item = tcx.hir().item(id);
                     match item.kind {
                         hir::ItemKind::Mod(_) => {
-                            as_keyword(Res::Def(DefKind::Mod, id.def_id.to_def_id()))
+                            as_keyword(Res::Def(DefKind::Mod, id.owner_id.to_def_id()))
                         }
                         hir::ItemKind::Use(path, hir::UseKind::Single)
-                            if tcx.visibility(id.def_id).is_public() =>
+                            if tcx.visibility(id.owner_id).is_public() =>
                         {
                             as_keyword(path.res.expect_non_local())
-                                .map(|(_, prim)| (id.def_id.to_def_id(), prim))
+                                .map(|(_, prim)| (id.owner_id.to_def_id(), prim))
                         }
                         _ => None,
                     }
@@ -308,14 +306,14 @@ impl ExternalCrate {
                     let item = tcx.hir().item(id);
                     match item.kind {
                         hir::ItemKind::Mod(_) => {
-                            as_primitive(Res::Def(DefKind::Mod, id.def_id.to_def_id()))
+                            as_primitive(Res::Def(DefKind::Mod, id.owner_id.to_def_id()))
                         }
                         hir::ItemKind::Use(path, hir::UseKind::Single)
-                            if tcx.visibility(id.def_id).is_public() =>
+                            if tcx.visibility(id.owner_id).is_public() =>
                         {
                             as_primitive(path.res.expect_non_local()).map(|(_, prim)| {
                                 // Pretend the primitive is local.
-                                (id.def_id.to_def_id(), prim)
+                                (id.owner_id.to_def_id(), prim)
                             })
                         }
                         _ => None,
@@ -348,12 +346,12 @@ pub(crate) struct Item {
     /// Optional because not every item has a name, e.g. impls.
     pub(crate) name: Option<Symbol>,
     pub(crate) attrs: Box<Attributes>,
-    pub(crate) visibility: Visibility,
     /// Information about this item that is specific to what kind of item it is.
     /// E.g., struct vs enum vs function.
     pub(crate) kind: Box<ItemKind>,
     pub(crate) item_id: ItemId,
-
+    /// This is the `DefId` of the `use` statement if the item was inlined.
+    pub(crate) inline_stmt_id: Option<DefId>,
     pub(crate) cfg: Option<Arc<Cfg>>,
 }
 
@@ -364,9 +362,7 @@ impl fmt::Debug for Item {
         let alternate = f.alternate();
         // hand-picked fields that don't bloat the logs too much
         let mut fmt = f.debug_struct("Item");
-        fmt.field("name", &self.name)
-            .field("visibility", &self.visibility)
-            .field("item_id", &self.item_id);
+        fmt.field("name", &self.name).field("item_id", &self.item_id);
         // allow printing the full item if someone really wants to
         if alternate {
             fmt.field("attrs", &self.attrs).field("kind", &self.kind).field("cfg", &self.cfg);
@@ -388,6 +384,15 @@ pub(crate) fn rustc_span(def_id: DefId, tcx: TyCtxt<'_>) -> Span {
     ))
 }
 
+fn is_field_vis_inherited(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
+    let parent = tcx.parent(def_id);
+    match tcx.def_kind(parent) {
+        DefKind::Struct | DefKind::Union => false,
+        DefKind::Variant => true,
+        parent_kind => panic!("unexpected parent kind: {:?}", parent_kind),
+    }
+}
+
 impl Item {
     pub(crate) fn stability<'tcx>(&self, tcx: TyCtxt<'tcx>) -> Option<Stability> {
         self.item_id.as_def_id().and_then(|did| tcx.lookup_stability(did))
@@ -462,7 +467,6 @@ impl Item {
             name,
             kind,
             Box::new(Attributes::from_ast(ast_attrs)),
-            cx,
             ast_attrs.cfg(cx.tcx, &cx.cache.hidden_cfg),
         )
     }
@@ -472,21 +476,18 @@ impl Item {
         name: Option<Symbol>,
         kind: ItemKind,
         attrs: Box<Attributes>,
-        cx: &mut DocContext<'_>,
         cfg: Option<Arc<Cfg>>,
     ) -> Item {
         trace!("name={:?}, def_id={:?} cfg={:?}", name, def_id, cfg);
 
-        // Primitives and Keywords are written in the source code as private modules.
-        // The modules need to be private so that nobody actually uses them, but the
-        // keywords and primitives that they are documenting are public.
-        let visibility = if matches!(&kind, ItemKind::KeywordItem | ItemKind::PrimitiveItem(..)) {
-            Visibility::Public
-        } else {
-            clean_visibility(cx.tcx.visibility(def_id))
-        };
-
-        Item { item_id: def_id.into(), kind: Box::new(kind), name, attrs, visibility, cfg }
+        Item {
+            item_id: def_id.into(),
+            kind: Box::new(kind),
+            name,
+            attrs,
+            cfg,
+            inline_stmt_id: None,
+        }
     }
 
     /// Finds all `doc` attributes as NameValues and returns their corresponding values, joined
@@ -691,17 +692,61 @@ impl Item {
                     asyncness: hir::IsAsync::NotAsync,
                 }
             }
-            ItemKind::FunctionItem(_) | ItemKind::MethodItem(_, _) => {
+            ItemKind::FunctionItem(_) | ItemKind::MethodItem(_, _) | ItemKind::TyMethodItem(_) => {
                 let def_id = self.item_id.as_def_id().unwrap();
                 build_fn_header(def_id, tcx, tcx.asyncness(def_id))
             }
-            ItemKind::TyMethodItem(_) => {
-                build_fn_header(self.item_id.as_def_id().unwrap(), tcx, hir::IsAsync::NotAsync)
-            }
             _ => return None,
         };
         Some(header)
     }
+
+    /// Returns the visibility of the current item. If the visibility is "inherited", then `None`
+    /// is returned.
+    pub(crate) fn visibility(&self, tcx: TyCtxt<'_>) -> Option<Visibility<DefId>> {
+        let def_id = match self.item_id {
+            // Anything but DefId *shouldn't* matter, but return a reasonable value anyway.
+            ItemId::Auto { .. } | ItemId::Blanket { .. } => return None,
+            // Primitives and Keywords are written in the source code as private modules.
+            // The modules need to be private so that nobody actually uses them, but the
+            // keywords and primitives that they are documenting are public.
+            ItemId::Primitive(..) => return Some(Visibility::Public),
+            ItemId::DefId(def_id) => def_id,
+        };
+
+        match *self.kind {
+            // Explication on `ItemId::Primitive` just above.
+            ItemKind::KeywordItem | ItemKind::PrimitiveItem(_) => return Some(Visibility::Public),
+            // Variant fields inherit their enum's visibility.
+            StructFieldItem(..) if is_field_vis_inherited(tcx, def_id) => {
+                return None;
+            }
+            // Variants always inherit visibility
+            VariantItem(..) => return None,
+            // Trait items inherit the trait's visibility
+            AssocConstItem(..) | TyAssocConstItem(..) | AssocTypeItem(..) | TyAssocTypeItem(..)
+            | TyMethodItem(..) | MethodItem(..) => {
+                let assoc_item = tcx.associated_item(def_id);
+                let is_trait_item = match assoc_item.container {
+                    ty::TraitContainer => true,
+                    ty::ImplContainer => {
+                        // Trait impl items always inherit the impl's visibility --
+                        // we don't want to show `pub`.
+                        tcx.impl_trait_ref(tcx.parent(assoc_item.def_id)).is_some()
+                    }
+                };
+                if is_trait_item {
+                    return None;
+                }
+            }
+            _ => {}
+        }
+        let def_id = match self.inline_stmt_id {
+            Some(inlined) => inlined,
+            None => def_id,
+        };
+        Some(tcx.visibility(def_id))
+    }
 }
 
 #[derive(Clone, Debug)]
@@ -747,7 +792,7 @@ pub(crate) enum ItemKind {
     /// A required associated type in a trait declaration.
     ///
     /// The bounds may be non-empty if there is a `where` clause.
-    TyAssocTypeItem(Box<Generics>, Vec<GenericBound>),
+    TyAssocTypeItem(Generics, Vec<GenericBound>),
     /// An associated type in a trait impl or a provided one in a trait declaration.
     AssocTypeItem(Box<Typedef>, Vec<GenericBound>),
     /// An item that has been stripped by a rustdoc pass
@@ -1392,6 +1437,10 @@ pub(crate) struct GenericParamDef {
 }
 
 impl GenericParamDef {
+    pub(crate) fn lifetime(name: Symbol) -> Self {
+        Self { name, kind: GenericParamDefKind::Lifetime { outlives: Vec::new() } }
+    }
+
     pub(crate) fn is_synthetic_type_param(&self) -> bool {
         match self.kind {
             GenericParamDefKind::Lifetime { .. } | GenericParamDefKind::Const { .. } => false,
@@ -1414,8 +1463,8 @@ impl GenericParamDef {
 // maybe use a Generic enum and use Vec<Generic>?
 #[derive(Clone, Debug, Default)]
 pub(crate) struct Generics {
-    pub(crate) params: Vec<GenericParamDef>,
-    pub(crate) where_predicates: Vec<WherePredicate>,
+    pub(crate) params: ThinVec<GenericParamDef>,
+    pub(crate) where_predicates: ThinVec<WherePredicate>,
 }
 
 impl Generics {
@@ -1576,7 +1625,7 @@ pub(crate) enum Type {
     /// An array type.
     ///
     /// The `String` field is a stringified version of the array's length parameter.
-    Array(Box<Type>, String),
+    Array(Box<Type>, Box<str>),
     /// A raw pointer type: `*const i32`, `*mut i32`
     RawPointer(Mutability, Box<Type>),
     /// A reference type: `&i32`, `&'a mut Foo`
@@ -2030,24 +2079,6 @@ impl From<hir::PrimTy> for PrimitiveType {
     }
 }
 
-#[derive(Copy, Clone, Debug)]
-pub(crate) enum Visibility {
-    /// `pub`
-    Public,
-    /// Visibility inherited from parent.
-    ///
-    /// For example, this is the visibility of private items and of enum variants.
-    Inherited,
-    /// `pub(crate)`, `pub(super)`, or `pub(in path::to::somewhere)`
-    Restricted(DefId),
-}
-
-impl Visibility {
-    pub(crate) fn is_public(&self) -> bool {
-        matches!(self, Visibility::Public)
-    }
-}
-
 #[derive(Clone, Debug)]
 pub(crate) struct Struct {
     pub(crate) struct_type: CtorKind,
@@ -2179,7 +2210,7 @@ impl Span {
 #[derive(Clone, PartialEq, Eq, Debug, Hash)]
 pub(crate) struct Path {
     pub(crate) res: Res,
-    pub(crate) segments: Vec<PathSegment>,
+    pub(crate) segments: ThinVec<PathSegment>,
 }
 
 impl Path {
@@ -2329,7 +2360,7 @@ pub(crate) enum ConstantKind {
     ///
     /// Note that `ty::Const` includes generic parameters, and may not always be uniquely identified
     /// by a DefId. So this field must be different from `Extern`.
-    TyConst { expr: String },
+    TyConst { expr: Box<str> },
     /// A constant (expression) that's not an item or associated item. These are usually found
     /// nested inside types (e.g., array lengths) or expressions (e.g., repeat counts), and also
     /// used to define explicit discriminant values for enum variants.
@@ -2357,7 +2388,7 @@ impl Constant {
 impl ConstantKind {
     pub(crate) fn expr(&self, tcx: TyCtxt<'_>) -> String {
         match *self {
-            ConstantKind::TyConst { ref expr } => expr.clone(),
+            ConstantKind::TyConst { ref expr } => expr.to_string(),
             ConstantKind::Extern { def_id } => print_inlined_const(tcx, def_id),
             ConstantKind::Local { body, .. } | ConstantKind::Anonymous { body } => {
                 print_const_expr(tcx, body)
@@ -2543,12 +2574,13 @@ mod size_asserts {
     // tidy-alphabetical-start
     static_assert_size!(Crate, 72); // frequently moved by-value
     static_assert_size!(DocFragment, 32);
-    static_assert_size!(GenericArg, 48);
+    static_assert_size!(GenericArg, 32);
     static_assert_size!(GenericArgs, 32);
     static_assert_size!(GenericParamDef, 56);
+    static_assert_size!(Generics, 16);
     static_assert_size!(Item, 56);
-    static_assert_size!(ItemKind, 88);
+    static_assert_size!(ItemKind, 64);
     static_assert_size!(PathSegment, 40);
-    static_assert_size!(Type, 48);
+    static_assert_size!(Type, 32);
     // tidy-alphabetical-end
 }
diff --git a/src/librustdoc/clean/utils.rs b/src/librustdoc/clean/utils.rs
index 4572a712258a..21f8fbe36f17 100644
--- a/src/librustdoc/clean/utils.rs
+++ b/src/librustdoc/clean/utils.rs
@@ -4,11 +4,10 @@ use crate::clean::render_macro_matchers::render_macro_matcher;
 use crate::clean::{
     clean_doc_module, clean_middle_const, clean_middle_region, clean_middle_ty, inline, Crate,
     ExternalCrate, Generic, GenericArg, GenericArgs, ImportSource, Item, ItemKind, Lifetime, Path,
-    PathSegment, Primitive, PrimitiveType, Type, TypeBinding, Visibility,
+    PathSegment, Primitive, PrimitiveType, Term, Type, TypeBinding, TypeBindingKind,
 };
 use crate::core::DocContext;
-use crate::formats::item_type::ItemType;
-use crate::visit_lib::LibEmbargoVisitor;
+use crate::html::format::visibility_to_src_with_space;
 
 use rustc_ast as ast;
 use rustc_ast::tokenstream::TokenTree;
@@ -22,7 +21,7 @@ use rustc_middle::ty::{self, DefIdTree, TyCtxt};
 use rustc_span::symbol::{kw, sym, Symbol};
 use std::fmt::Write as _;
 use std::mem;
-use thin_vec::ThinVec;
+use thin_vec::{thin_vec, ThinVec};
 
 #[cfg(test)]
 mod tests;
@@ -32,7 +31,7 @@ pub(crate) fn krate(cx: &mut DocContext<'_>) -> Crate {
 
     for &cnum in cx.tcx.crates(()) {
         // Analyze doc-reachability for extern items
-        LibEmbargoVisitor::new(cx).visit_lib(cnum);
+        crate::visit_lib::lib_embargo_visit_item(cx, cnum.as_def_id());
     }
 
     // Clean the crate, translating the entire librustc_ast AST to one that is
@@ -114,12 +113,12 @@ fn external_generic_args<'tcx>(
                 ty::Tuple(tys) => tys.iter().map(|t| clean_middle_ty(t, cx, None)).collect::<Vec<_>>().into(),
                 _ => return GenericArgs::AngleBracketed { args: args.into(), bindings },
             };
-        let output = None;
-        // FIXME(#20299) return type comes from a projection now
-        // match types[1].kind {
-        //     ty::Tuple(ref v) if v.is_empty() => None, // -> ()
-        //     _ => Some(types[1].clean(cx))
-        // };
+        let output = bindings.into_iter().next().and_then(|binding| match binding.kind {
+            TypeBindingKind::Equality { term: Term::Type(ty) } if ty != Type::Tuple(Vec::new()) => {
+                Some(Box::new(ty))
+            }
+            _ => None,
+        });
         GenericArgs::Parenthesized { inputs, output }
     } else {
         GenericArgs::AngleBracketed { args: args.into(), bindings: bindings.into() }
@@ -137,7 +136,7 @@ pub(super) fn external_path<'tcx>(
     let name = cx.tcx.item_name(did);
     Path {
         res: Res::Def(def_kind, did),
-        segments: vec![PathSegment {
+        segments: thin_vec![PathSegment {
             name,
             args: external_generic_args(cx, did, has_self, bindings, substs),
         }],
@@ -243,19 +242,13 @@ pub(crate) fn print_const(cx: &DocContext<'_>, n: ty::Const<'_>) -> String {
 
             s
         }
-        _ => {
-            let mut s = n.to_string();
-            // array lengths are obviously usize
-            if s.ends_with("_usize") {
-                let n = s.len() - "_usize".len();
-                s.truncate(n);
-                if s.ends_with(": ") {
-                    let n = s.len() - ": ".len();
-                    s.truncate(n);
-                }
-            }
-            s
+        // array lengths are obviously usize
+        ty::ConstKind::Value(ty::ValTree::Leaf(scalar))
+            if *n.ty().kind() == ty::Uint(ty::UintTy::Usize) =>
+        {
+            scalar.to_string()
         }
+        _ => n.to_string(),
     }
 }
 
@@ -504,9 +497,6 @@ pub(crate) fn register_res(cx: &mut DocContext<'_>, res: Res) -> DefId {
         return did;
     }
     inline::record_extern_fqn(cx, did, kind);
-    if let ItemType::Trait = kind {
-        inline::record_extern_trait(cx, did);
-    }
     did
 }
 
@@ -588,7 +578,7 @@ pub(super) fn display_macro_source(
     name: Symbol,
     def: &ast::MacroDef,
     def_id: DefId,
-    vis: Visibility,
+    vis: ty::Visibility<DefId>,
 ) -> String {
     let tts: Vec<_> = def.body.inner_tokens().into_trees().collect();
     // Extract the spans of all matchers. They represent the "interface" of the macro.
@@ -600,14 +590,14 @@ pub(super) fn display_macro_source(
         if matchers.len() <= 1 {
             format!(
                 "{}macro {}{} {{\n    ...\n}}",
-                vis.to_src_with_space(cx.tcx, def_id),
+                visibility_to_src_with_space(Some(vis), cx.tcx, def_id),
                 name,
                 matchers.map(|matcher| render_macro_matcher(cx.tcx, matcher)).collect::<String>(),
             )
         } else {
             format!(
                 "{}macro {} {{\n{}}}",
-                vis.to_src_with_space(cx.tcx, def_id),
+                visibility_to_src_with_space(Some(vis), cx.tcx, def_id),
                 name,
                 render_macro_arms(cx.tcx, matchers, ","),
             )
diff --git a/src/librustdoc/config.rs b/src/librustdoc/config.rs
index 67ea39fb9657..789dd398be50 100644
--- a/src/librustdoc/config.rs
+++ b/src/librustdoc/config.rs
@@ -239,9 +239,6 @@ pub(crate) struct RenderOptions {
     pub(crate) default_settings: FxHashMap<String, String>,
     /// If present, suffix added to CSS/JavaScript files when referencing them in generated pages.
     pub(crate) resource_suffix: String,
-    /// Whether to run the static CSS/JavaScript through a minifier when outputting them. `true` by
-    /// default.
-    pub(crate) enable_minification: bool,
     /// Whether to create an index page in the root of the output directory. If this is true but
     /// `enable_index_page` is None, generate a static listing of crates instead.
     pub(crate) enable_index_page: bool,
@@ -329,7 +326,7 @@ impl Options {
             crate::usage("rustdoc");
             return Err(0);
         } else if matches.opt_present("version") {
-            rustc_driver::version("rustdoc", matches);
+            rustc_driver::version!("rustdoc", matches);
             return Err(0);
         }
 
@@ -416,7 +413,9 @@ impl Options {
 
         let to_check = matches.opt_strs("check-theme");
         if !to_check.is_empty() {
-            let paths = match theme::load_css_paths(static_files::themes::LIGHT) {
+            let paths = match theme::load_css_paths(
+                std::str::from_utf8(static_files::STATIC_FILES.theme_light_css.bytes).unwrap(),
+            ) {
                 Ok(p) => p,
                 Err(e) => {
                     diag.struct_err(&e.to_string()).emit();
@@ -557,7 +556,9 @@ impl Options {
 
         let mut themes = Vec::new();
         if matches.opt_present("theme") {
-            let paths = match theme::load_css_paths(static_files::themes::LIGHT) {
+            let paths = match theme::load_css_paths(
+                std::str::from_utf8(static_files::STATIC_FILES.theme_light_css.bytes).unwrap(),
+            ) {
                 Ok(p) => p,
                 Err(e) => {
                     diag.struct_err(&e.to_string()).emit();
@@ -675,7 +676,6 @@ impl Options {
             ModuleSorting::Alphabetical
         };
         let resource_suffix = matches.opt_str("resource-suffix").unwrap_or_default();
-        let enable_minification = !matches.opt_present("disable-minification");
         let markdown_no_toc = matches.opt_present("markdown-no-toc");
         let markdown_css = matches.opt_strs("markdown-css");
         let markdown_playground_url = matches.opt_str("markdown-playground-url");
@@ -768,7 +768,6 @@ impl Options {
             extern_html_root_takes_precedence,
             default_settings,
             resource_suffix,
-            enable_minification,
             enable_index_page,
             index_page,
             static_root_path,
diff --git a/src/librustdoc/core.rs b/src/librustdoc/core.rs
index 8232353f915b..893249e88cf7 100644
--- a/src/librustdoc/core.rs
+++ b/src/librustdoc/core.rs
@@ -1,6 +1,7 @@
 use rustc_ast::NodeId;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::sync::{self, Lrc};
+use rustc_data_structures::unord::UnordSet;
 use rustc_errors::emitter::{Emitter, EmitterWriter};
 use rustc_errors::json::JsonEmitter;
 use rustc_feature::UnstableFeatures;
@@ -165,6 +166,7 @@ pub(crate) fn new_handler(
                     unstable_opts.teach,
                     diagnostic_width,
                     false,
+                    unstable_opts.track_diagnostics,
                 )
                 .ui_testing(unstable_opts.ui_testing),
             )
@@ -183,6 +185,7 @@ pub(crate) fn new_handler(
                     json_rendered,
                     diagnostic_width,
                     false,
+                    unstable_opts.track_diagnostics,
                 )
                 .ui_testing(unstable_opts.ui_testing),
             )
@@ -288,8 +291,7 @@ pub(crate) fn create_config(
             providers.typeck_item_bodies = |_, _| {};
             // hack so that `used_trait_imports` won't try to call typeck
             providers.used_trait_imports = |_, _| {
-                static EMPTY_SET: LazyLock<FxHashSet<LocalDefId>> =
-                    LazyLock::new(FxHashSet::default);
+                static EMPTY_SET: LazyLock<UnordSet<LocalDefId>> = LazyLock::new(UnordSet::default);
                 &EMPTY_SET
             };
             // In case typeck does end up being called, don't ICE in case there were name resolution errors
@@ -348,7 +350,6 @@ pub(crate) fn run_global_ctxt(
 
     let auto_traits =
         tcx.all_traits().filter(|&trait_def_id| tcx.trait_is_auto(trait_def_id)).collect();
-    let access_levels = tcx.privacy_access_levels(()).map_id(Into::into);
 
     let mut ctxt = DocContext {
         tcx,
@@ -361,7 +362,7 @@ pub(crate) fn run_global_ctxt(
         impl_trait_bounds: Default::default(),
         generated_synthetics: Default::default(),
         auto_traits,
-        cache: Cache::new(access_levels, render_options.document_private),
+        cache: Cache::new(render_options.document_private),
         inlined: FxHashSet::default(),
         output_format,
         render_options,
diff --git a/src/librustdoc/doctest.rs b/src/librustdoc/doctest.rs
index db70029f6ec5..7cbe2f1e2273 100644
--- a/src/librustdoc/doctest.rs
+++ b/src/librustdoc/doctest.rs
@@ -551,6 +551,7 @@ pub(crate) fn make_test(
                 false,
                 Some(80),
                 false,
+                false,
             )
             .supports_color();
 
@@ -564,6 +565,7 @@ pub(crate) fn make_test(
                 false,
                 None,
                 false,
+                false,
             );
 
             // FIXME(misdreavus): pass `-Z treat-err-as-bug` to the doctest parser
@@ -748,6 +750,7 @@ fn check_if_attr_is_complete(source: &str, edition: Edition) -> bool {
                 false,
                 None,
                 false,
+                false,
             );
 
             let handler = Handler::with_emitter(false, None, Box::new(emitter));
diff --git a/src/librustdoc/formats/cache.rs b/src/librustdoc/formats/cache.rs
index 2e428cfddcf0..d027fb6e8763 100644
--- a/src/librustdoc/formats/cache.rs
+++ b/src/librustdoc/formats/cache.rs
@@ -2,7 +2,6 @@ use std::mem;
 
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_hir::def_id::{CrateNum, DefId};
-use rustc_middle::middle::privacy::AccessLevels;
 use rustc_middle::ty::{self, TyCtxt};
 use rustc_span::Symbol;
 
@@ -15,6 +14,7 @@ use crate::html::format::join_with_double_colon;
 use crate::html::markdown::short_markdown_summary;
 use crate::html::render::search_index::get_function_type_for_search;
 use crate::html::render::IndexItem;
+use crate::visit_lib::RustdocEffectiveVisibilities;
 
 /// This cache is used to store information about the [`clean::Crate`] being
 /// rendered in order to provide more useful documentation. This contains
@@ -77,8 +77,8 @@ pub(crate) struct Cache {
 
     // Note that external items for which `doc(hidden)` applies to are shown as
     // non-reachable while local items aren't. This is because we're reusing
-    // the access levels from the privacy check pass.
-    pub(crate) access_levels: AccessLevels<DefId>,
+    // the effective visibilities from the privacy check pass.
+    pub(crate) effective_visibilities: RustdocEffectiveVisibilities,
 
     /// The version of the crate being documented, if given from the `--crate-version` flag.
     pub(crate) crate_version: Option<String>,
@@ -132,8 +132,8 @@ struct CacheBuilder<'a, 'tcx> {
 }
 
 impl Cache {
-    pub(crate) fn new(access_levels: AccessLevels<DefId>, document_private: bool) -> Self {
-        Cache { access_levels, document_private, ..Cache::default() }
+    pub(crate) fn new(document_private: bool) -> Self {
+        Cache { document_private, ..Cache::default() }
     }
 
     /// Populates the `Cache` with more data. The returned `Crate` will be missing some data that was
@@ -316,21 +316,28 @@ impl<'a, 'tcx> DocFolder for CacheBuilder<'a, 'tcx> {
                         let desc = item.doc_value().map_or_else(String::new, |x| {
                             short_markdown_summary(x.as_str(), &item.link_names(self.cache))
                         });
-                        self.cache.search_index.push(IndexItem {
-                            ty: item.type_(),
-                            name: s.to_string(),
-                            path: join_with_double_colon(path),
-                            desc,
-                            parent,
-                            parent_idx: None,
-                            search_type: get_function_type_for_search(
-                                &item,
-                                self.tcx,
-                                clean_impl_generics(self.cache.parent_stack.last()).as_ref(),
-                                self.cache,
-                            ),
-                            aliases: item.attrs.get_doc_aliases(),
-                        });
+                        let ty = item.type_();
+                        let name = s.to_string();
+                        if ty != ItemType::StructField || u16::from_str_radix(&name, 10).is_err() {
+                            // In case this is a field from a tuple struct, we don't add it into
+                            // the search index because its name is something like "0", which is
+                            // not useful for rustdoc search.
+                            self.cache.search_index.push(IndexItem {
+                                ty,
+                                name,
+                                path: join_with_double_colon(path),
+                                desc,
+                                parent,
+                                parent_idx: None,
+                                search_type: get_function_type_for_search(
+                                    &item,
+                                    self.tcx,
+                                    clean_impl_generics(self.cache.parent_stack.last()).as_ref(),
+                                    self.cache,
+                                ),
+                                aliases: item.attrs.get_doc_aliases(),
+                            });
+                        }
                     }
                 }
                 (Some(parent), None) if is_inherent_impl_item => {
@@ -381,7 +388,10 @@ impl<'a, 'tcx> DocFolder for CacheBuilder<'a, 'tcx> {
                     // paths map if there was already an entry present and we're
                     // not a public item.
                     if !self.cache.paths.contains_key(&item.item_id.expect_def_id())
-                        || self.cache.access_levels.is_public(item.item_id.expect_def_id())
+                        || self
+                            .cache
+                            .effective_visibilities
+                            .is_directly_public(self.tcx, item.item_id.expect_def_id())
                     {
                         self.cache.paths.insert(
                             item.item_id.expect_def_id(),
diff --git a/src/librustdoc/html/format.rs b/src/librustdoc/html/format.rs
index 7d00002d05be..39e2a9022267 100644
--- a/src/librustdoc/html/format.rs
+++ b/src/librustdoc/html/format.rs
@@ -107,10 +107,6 @@ impl Buffer {
         self.buffer
     }
 
-    pub(crate) fn insert_str(&mut self, idx: usize, s: &str) {
-        self.buffer.insert_str(idx, s);
-    }
-
     pub(crate) fn push_str(&mut self, s: &str) {
         self.buffer.push_str(s);
     }
@@ -659,7 +655,7 @@ pub(crate) fn href_with_root_path(
     }
 
     if !did.is_local()
-        && !cache.access_levels.is_public(did)
+        && !cache.effective_visibilities.is_directly_public(tcx, did)
         && !cache.document_private
         && !cache.primitive_locations.values().any(|&id| id == did)
     {
@@ -1232,9 +1228,8 @@ impl clean::Arguments {
     ) -> impl fmt::Display + 'a + Captures<'tcx> {
         display_fn(move |f| {
             for (i, input) in self.values.iter().enumerate() {
-                if !input.name.is_empty() {
-                    write!(f, "{}: ", input.name)?;
-                }
+                write!(f, "{}: ", input.name)?;
+
                 if f.alternate() {
                     write!(f, "{:#}", input.type_.print(cx))?;
                 } else {
@@ -1367,10 +1362,8 @@ impl clean::FnDecl {
                     args.push_str("const ");
                     args_plain.push_str("const ");
                 }
-                if !input.name.is_empty() {
-                    write!(args, "{}: ", input.name);
-                    write!(args_plain, "{}: ", input.name);
-                }
+                write!(args, "{}: ", input.name);
+                write!(args_plain, "{}: ", input.name);
 
                 if f.alternate() {
                     write!(args, "{:#}", input.type_.print(cx));
@@ -1420,87 +1413,84 @@ impl clean::FnDecl {
     }
 }
 
-impl clean::Visibility {
-    pub(crate) fn print_with_space<'a, 'tcx: 'a>(
-        self,
-        item_did: ItemId,
-        cx: &'a Context<'tcx>,
-    ) -> impl fmt::Display + 'a + Captures<'tcx> {
-        use std::fmt::Write as _;
+pub(crate) fn visibility_print_with_space<'a, 'tcx: 'a>(
+    visibility: Option<ty::Visibility<DefId>>,
+    item_did: ItemId,
+    cx: &'a Context<'tcx>,
+) -> impl fmt::Display + 'a + Captures<'tcx> {
+    use std::fmt::Write as _;
 
-        let to_print: Cow<'static, str> = match self {
-            clean::Public => "pub ".into(),
-            clean::Inherited => "".into(),
-            clean::Visibility::Restricted(vis_did) => {
-                // FIXME(camelid): This may not work correctly if `item_did` is a module.
-                //                 However, rustdoc currently never displays a module's
-                //                 visibility, so it shouldn't matter.
-                let parent_module = find_nearest_parent_module(cx.tcx(), item_did.expect_def_id());
+    let to_print: Cow<'static, str> = match visibility {
+        None => "".into(),
+        Some(ty::Visibility::Public) => "pub ".into(),
+        Some(ty::Visibility::Restricted(vis_did)) => {
+            // FIXME(camelid): This may not work correctly if `item_did` is a module.
+            //                 However, rustdoc currently never displays a module's
+            //                 visibility, so it shouldn't matter.
+            let parent_module = find_nearest_parent_module(cx.tcx(), item_did.expect_def_id());
 
-                if vis_did.is_crate_root() {
-                    "pub(crate) ".into()
-                } else if parent_module == Some(vis_did) {
-                    // `pub(in foo)` where `foo` is the parent module
-                    // is the same as no visibility modifier
-                    "".into()
-                } else if parent_module
-                    .and_then(|parent| find_nearest_parent_module(cx.tcx(), parent))
-                    == Some(vis_did)
-                {
-                    "pub(super) ".into()
-                } else {
-                    let path = cx.tcx().def_path(vis_did);
-                    debug!("path={:?}", path);
-                    // modified from `resolved_path()` to work with `DefPathData`
-                    let last_name = path.data.last().unwrap().data.get_opt_name().unwrap();
-                    let anchor = anchor(vis_did, last_name, cx).to_string();
+            if vis_did.is_crate_root() {
+                "pub(crate) ".into()
+            } else if parent_module == Some(vis_did) {
+                // `pub(in foo)` where `foo` is the parent module
+                // is the same as no visibility modifier
+                "".into()
+            } else if parent_module.and_then(|parent| find_nearest_parent_module(cx.tcx(), parent))
+                == Some(vis_did)
+            {
+                "pub(super) ".into()
+            } else {
+                let path = cx.tcx().def_path(vis_did);
+                debug!("path={:?}", path);
+                // modified from `resolved_path()` to work with `DefPathData`
+                let last_name = path.data.last().unwrap().data.get_opt_name().unwrap();
+                let anchor = anchor(vis_did, last_name, cx).to_string();
 
-                    let mut s = "pub(in ".to_owned();
-                    for seg in &path.data[..path.data.len() - 1] {
-                        let _ = write!(s, "{}::", seg.data.get_opt_name().unwrap());
-                    }
-                    let _ = write!(s, "{}) ", anchor);
-                    s.into()
+                let mut s = "pub(in ".to_owned();
+                for seg in &path.data[..path.data.len() - 1] {
+                    let _ = write!(s, "{}::", seg.data.get_opt_name().unwrap());
                 }
+                let _ = write!(s, "{}) ", anchor);
+                s.into()
             }
-        };
-        display_fn(move |f| write!(f, "{}", to_print))
-    }
+        }
+    };
+    display_fn(move |f| write!(f, "{}", to_print))
+}
 
-    /// This function is the same as print_with_space, except that it renders no links.
-    /// It's used for macros' rendered source view, which is syntax highlighted and cannot have
-    /// any HTML in it.
-    pub(crate) fn to_src_with_space<'a, 'tcx: 'a>(
-        self,
-        tcx: TyCtxt<'tcx>,
-        item_did: DefId,
-    ) -> impl fmt::Display + 'a + Captures<'tcx> {
-        let to_print = match self {
-            clean::Public => "pub ".to_owned(),
-            clean::Inherited => String::new(),
-            clean::Visibility::Restricted(vis_did) => {
-                // FIXME(camelid): This may not work correctly if `item_did` is a module.
-                //                 However, rustdoc currently never displays a module's
-                //                 visibility, so it shouldn't matter.
-                let parent_module = find_nearest_parent_module(tcx, item_did);
+/// This function is the same as print_with_space, except that it renders no links.
+/// It's used for macros' rendered source view, which is syntax highlighted and cannot have
+/// any HTML in it.
+pub(crate) fn visibility_to_src_with_space<'a, 'tcx: 'a>(
+    visibility: Option<ty::Visibility<DefId>>,
+    tcx: TyCtxt<'tcx>,
+    item_did: DefId,
+) -> impl fmt::Display + 'a + Captures<'tcx> {
+    let to_print = match visibility {
+        None => String::new(),
+        Some(ty::Visibility::Public) => "pub ".to_owned(),
+        Some(ty::Visibility::Restricted(vis_did)) => {
+            // FIXME(camelid): This may not work correctly if `item_did` is a module.
+            //                 However, rustdoc currently never displays a module's
+            //                 visibility, so it shouldn't matter.
+            let parent_module = find_nearest_parent_module(tcx, item_did);
 
-                if vis_did.is_crate_root() {
-                    "pub(crate) ".to_owned()
-                } else if parent_module == Some(vis_did) {
-                    // `pub(in foo)` where `foo` is the parent module
-                    // is the same as no visibility modifier
-                    String::new()
-                } else if parent_module.and_then(|parent| find_nearest_parent_module(tcx, parent))
-                    == Some(vis_did)
-                {
-                    "pub(super) ".to_owned()
-                } else {
-                    format!("pub(in {}) ", tcx.def_path_str(vis_did))
-                }
+            if vis_did.is_crate_root() {
+                "pub(crate) ".to_owned()
+            } else if parent_module == Some(vis_did) {
+                // `pub(in foo)` where `foo` is the parent module
+                // is the same as no visibility modifier
+                String::new()
+            } else if parent_module.and_then(|parent| find_nearest_parent_module(tcx, parent))
+                == Some(vis_did)
+            {
+                "pub(super) ".to_owned()
+            } else {
+                format!("pub(in {}) ", tcx.def_path_str(vis_did))
             }
-        };
-        display_fn(move |f| f.write_str(&to_print))
-    }
+        }
+    };
+    display_fn(move |f| f.write_str(&to_print))
 }
 
 pub(crate) trait PrintWithSpace {
diff --git a/src/librustdoc/html/highlight.rs b/src/librustdoc/html/highlight.rs
index 5e28204b21d8..cd8c8c463b1a 100644
--- a/src/librustdoc/html/highlight.rs
+++ b/src/librustdoc/html/highlight.rs
@@ -72,8 +72,12 @@ pub(crate) fn render_source_with_highlighting(
     line_numbers: Buffer,
     href_context: HrefContext<'_, '_, '_>,
     decoration_info: DecorationInfo,
+    extra: Option<&str>,
 ) {
     write_header(out, "", Some(line_numbers), Tooltip::None);
+    if let Some(extra) = extra {
+        out.push_str(extra);
+    }
     write_code(out, src, Some(href_context), Some(decoration_info));
     write_footer(out, None);
 }
@@ -358,7 +362,7 @@ impl Class {
         match self {
             Class::Comment => "comment",
             Class::DocComment => "doccomment",
-            Class::Attribute => "attribute",
+            Class::Attribute => "attr",
             Class::KeyWord => "kw",
             Class::RefKeyWord => "kw-2",
             Class::Self_(_) => "self",
diff --git a/src/librustdoc/html/highlight/fixtures/sample.html b/src/librustdoc/html/highlight/fixtures/sample.html
index 4a5a3cf609cd..fced2eacd9e7 100644
--- a/src/librustdoc/html/highlight/fixtures/sample.html
+++ b/src/librustdoc/html/highlight/fixtures/sample.html
@@ -3,16 +3,16 @@
 .kw { color: #8959A8; }
 .kw-2, .prelude-ty { color: #4271AE; }
 .number, .string { color: #718C00; }
-.self, .bool-val, .prelude-val, .attribute, .attribute .ident { color: #C82829; }
+.self, .bool-val, .prelude-val, .attr, .attr .ident { color: #C82829; }
 .macro, .macro-nonterminal { color: #3E999F; }
 .lifetime { color: #B76514; }
 .question-mark { color: #ff9011; }
 </style>
-<pre><code><span class="attribute">#![crate_type = <span class="string">&quot;lib&quot;</span>]
+<pre><code><span class="attr">#![crate_type = <span class="string">&quot;lib&quot;</span>]
 
 </span><span class="kw">use </span>std::path::{Path, PathBuf};
 
-<span class="attribute">#[cfg(target_os = <span class="string">&quot;linux&quot;</span>)]
+<span class="attr">#[cfg(target_os = <span class="string">&quot;linux&quot;</span>)]
 #[cfg(target_os = <span class="string">&quot;windows&quot;</span>)]
 </span><span class="kw">fn </span>main() -&gt; () {
     <span class="kw">let </span>foo = <span class="bool-val">true </span>&amp;&amp; <span class="bool-val">false </span>|| <span class="bool-val">true</span>;
@@ -23,7 +23,7 @@
     <span class="macro">mac!</span>(foo, <span class="kw-2">&amp;mut </span>bar);
     <span class="macro">assert!</span>(<span class="self">self</span>.length &lt; N &amp;&amp; index &lt;= <span class="self">self</span>.length);
     ::std::env::var(<span class="string">&quot;gateau&quot;</span>).is_ok();
-    <span class="attribute">#[rustfmt::skip]
+    <span class="attr">#[rustfmt::skip]
     </span><span class="kw">let </span>s:std::path::PathBuf = std::path::PathBuf::new();
     <span class="kw">let </span><span class="kw-2">mut </span>s = String::new();
 
diff --git a/src/librustdoc/html/highlight/tests.rs b/src/librustdoc/html/highlight/tests.rs
index a5e633df4344..2c93b9a097f4 100644
--- a/src/librustdoc/html/highlight/tests.rs
+++ b/src/librustdoc/html/highlight/tests.rs
@@ -9,7 +9,7 @@ const STYLE: &str = r#"
 .kw { color: #8959A8; }
 .kw-2, .prelude-ty { color: #4271AE; }
 .number, .string { color: #718C00; }
-.self, .bool-val, .prelude-val, .attribute, .attribute .ident { color: #C82829; }
+.self, .bool-val, .prelude-val, .attr, .attr .ident { color: #C82829; }
 .macro, .macro-nonterminal { color: #3E999F; }
 .lifetime { color: #B76514; }
 .question-mark { color: #ff9011; }
diff --git a/src/librustdoc/html/layout.rs b/src/librustdoc/html/layout.rs
index 7d6d4b71e2ea..a60e7cb10fa5 100644
--- a/src/librustdoc/html/layout.rs
+++ b/src/librustdoc/html/layout.rs
@@ -2,13 +2,14 @@ use std::path::PathBuf;
 
 use rustc_data_structures::fx::FxHashMap;
 
-use crate::error::Error;
 use crate::externalfiles::ExternalHtml;
 use crate::html::format::{Buffer, Print};
 use crate::html::render::{ensure_trailing_slash, StylePath};
 
 use askama::Template;
 
+use super::static_files::{StaticFiles, STATIC_FILES};
+
 #[derive(Clone)]
 pub(crate) struct Layout {
     pub(crate) logo: String,
@@ -34,17 +35,23 @@ pub(crate) struct Page<'a> {
 }
 
 impl<'a> Page<'a> {
-    pub(crate) fn get_static_root_path(&self) -> &str {
-        self.static_root_path.unwrap_or(self.root_path)
+    pub(crate) fn get_static_root_path(&self) -> String {
+        match self.static_root_path {
+            Some(s) => s.to_string(),
+            None => format!("{}static.files/", self.root_path),
+        }
     }
 }
 
 #[derive(Template)]
 #[template(path = "page.html")]
 struct PageLayout<'a> {
-    static_root_path: &'a str,
+    static_root_path: String,
     page: &'a Page<'a>,
     layout: &'a Layout,
+
+    files: &'static StaticFiles,
+
     themes: Vec<String>,
     sidebar: String,
     content: String,
@@ -61,19 +68,17 @@ pub(crate) fn render<T: Print, S: Print>(
 ) -> String {
     let static_root_path = page.get_static_root_path();
     let krate_with_trailing_slash = ensure_trailing_slash(&layout.krate).to_string();
-    let mut themes: Vec<String> = style_files
-        .iter()
-        .map(StylePath::basename)
-        .collect::<Result<_, Error>>()
-        .unwrap_or_default();
+    let mut themes: Vec<String> = style_files.iter().map(|s| s.basename().unwrap()).collect();
     themes.sort();
-    let rustdoc_version = rustc_interface::util::version_str().unwrap_or("unknown version");
+
+    let rustdoc_version = rustc_interface::util::version_str!().unwrap_or("unknown version");
     let content = Buffer::html().to_display(t); // Note: This must happen before making the sidebar.
     let sidebar = Buffer::html().to_display(sidebar);
     PageLayout {
         static_root_path,
         page,
         layout,
+        files: &STATIC_FILES,
         themes,
         sidebar,
         content,
diff --git a/src/librustdoc/html/render/context.rs b/src/librustdoc/html/render/context.rs
index 5733d1f9c79d..73690c86f4f7 100644
--- a/src/librustdoc/html/render/context.rs
+++ b/src/librustdoc/html/render/context.rs
@@ -32,7 +32,7 @@ use crate::html::escape::Escape;
 use crate::html::format::{join_with_double_colon, Buffer};
 use crate::html::markdown::{self, plain_text_summary, ErrorCodes, IdMap};
 use crate::html::url_parts_builder::UrlPartsBuilder;
-use crate::html::{layout, sources};
+use crate::html::{layout, sources, static_files};
 use crate::scrape_examples::AllCallLocations;
 use crate::try_err;
 
@@ -69,11 +69,13 @@ pub(crate) struct Context<'tcx> {
     /// the source files are present in the html rendering, then this will be
     /// `true`.
     pub(crate) include_sources: bool,
+    /// Collection of all types with notable traits referenced in the current module.
+    pub(crate) types_with_notable_traits: FxHashSet<clean::Type>,
 }
 
 // `Context` is cloned a lot, so we don't want the size to grow unexpectedly.
 #[cfg(all(not(windows), target_arch = "x86_64", target_pointer_width = "64"))]
-rustc_data_structures::static_assert_size!(Context<'_>, 128);
+rustc_data_structures::static_assert_size!(Context<'_>, 160);
 
 /// Shared mutable state used in [`Context`] and elsewhere.
 pub(crate) struct SharedContext<'tcx> {
@@ -498,7 +500,7 @@ impl<'tcx> FormatRenderer<'tcx> for Context<'tcx> {
         );
 
         let (sender, receiver) = channel();
-        let mut scx = SharedContext {
+        let scx = SharedContext {
             tcx,
             src_root,
             local_sources,
@@ -521,19 +523,6 @@ impl<'tcx> FormatRenderer<'tcx> for Context<'tcx> {
             call_locations,
         };
 
-        // Add the default themes to the `Vec` of stylepaths
-        //
-        // Note that these must be added before `sources::render` is called
-        // so that the resulting source pages are styled
-        //
-        // `light.css` is not disabled because it is the stylesheet that stays loaded
-        // by the browser as the theme stylesheet. The theme system (hackily) works by
-        // changing the href to this stylesheet. All other themes are disabled to
-        // prevent rule conflicts
-        scx.style_files.push(StylePath { path: PathBuf::from("light.css") });
-        scx.style_files.push(StylePath { path: PathBuf::from("dark.css") });
-        scx.style_files.push(StylePath { path: PathBuf::from("ayu.css") });
-
         let dst = output;
         scx.ensure_dir(&dst)?;
 
@@ -545,6 +534,7 @@ impl<'tcx> FormatRenderer<'tcx> for Context<'tcx> {
             deref_id_map: FxHashMap::default(),
             shared: Rc::new(scx),
             include_sources,
+            types_with_notable_traits: FxHashSet::default(),
         };
 
         if emit_crate {
@@ -573,6 +563,7 @@ impl<'tcx> FormatRenderer<'tcx> for Context<'tcx> {
             id_map: IdMap::new(),
             shared: Rc::clone(&self.shared),
             include_sources: self.include_sources,
+            types_with_notable_traits: FxHashSet::default(),
         }
     }
 
@@ -647,10 +638,11 @@ impl<'tcx> FormatRenderer<'tcx> for Context<'tcx> {
                         </section>\
                      </noscript>\
                      <link rel=\"stylesheet\" type=\"text/css\" \
-                         href=\"{root_path}settings{suffix}.css\">\
-                     <script defer src=\"{root_path}settings{suffix}.js\"></script>",
-                    root_path = page.static_root_path.unwrap_or(""),
-                    suffix = page.resource_suffix,
+                         href=\"{static_root_path}{settings_css}\">\
+                     <script defer src=\"{static_root_path}{settings_js}\"></script>",
+                    static_root_path = page.get_static_root_path(),
+                    settings_css = static_files::STATIC_FILES.settings_css,
+                    settings_js = static_files::STATIC_FILES.settings_js,
                 )
             },
             &shared.style_files,
@@ -815,6 +807,7 @@ impl<'tcx> FormatRenderer<'tcx> for Context<'tcx> {
                 }
             }
         }
+
         Ok(())
     }
 
diff --git a/src/librustdoc/html/render/mod.rs b/src/librustdoc/html/render/mod.rs
index eeec6f8fee77..8731efb5e874 100644
--- a/src/librustdoc/html/render/mod.rs
+++ b/src/librustdoc/html/render/mod.rs
@@ -59,7 +59,7 @@ use rustc_span::{
     symbol::{sym, Symbol},
     BytePos, FileName, RealFileName,
 };
-use serde::ser::SerializeSeq;
+use serde::ser::{SerializeMap, SerializeSeq};
 use serde::{Serialize, Serializer};
 
 use crate::clean::{self, ItemId, RenderedLink, SelfTy};
@@ -70,8 +70,8 @@ use crate::formats::{AssocItemRender, Impl, RenderMode};
 use crate::html::escape::Escape;
 use crate::html::format::{
     href, join_with_double_colon, print_abi_with_space, print_constness_with_space,
-    print_default_space, print_generic_bounds, print_where_clause, Buffer, Ending, HrefError,
-    PrintWithSpace,
+    print_default_space, print_generic_bounds, print_where_clause, visibility_print_with_space,
+    Buffer, Ending, HrefError, PrintWithSpace,
 };
 use crate::html::highlight;
 use crate::html::markdown::{
@@ -747,11 +747,12 @@ fn assoc_const(
     extra: &str,
     cx: &Context<'_>,
 ) {
+    let tcx = cx.tcx();
     write!(
         w,
         "{extra}{vis}const <a{href} class=\"constant\">{name}</a>: {ty}",
         extra = extra,
-        vis = it.visibility.print_with_space(it.item_id, cx),
+        vis = visibility_print_with_space(it.visibility(tcx), it.item_id, cx),
         href = assoc_href_attr(it, link, cx),
         name = it.name.as_ref().unwrap(),
         ty = ty.print(cx),
@@ -764,7 +765,7 @@ fn assoc_const(
         //        This hurts readability in this context especially when more complex expressions
         //        are involved and it doesn't add much of value.
         //        Find a way to print constants here without all that jazz.
-        write!(w, "{}", Escape(&default.value(cx.tcx()).unwrap_or_else(|| default.expr(cx.tcx()))));
+        write!(w, "{}", Escape(&default.value(tcx).unwrap_or_else(|| default.expr(tcx))));
     }
 }
 
@@ -802,17 +803,18 @@ fn assoc_method(
     d: &clean::FnDecl,
     link: AssocItemLink<'_>,
     parent: ItemType,
-    cx: &Context<'_>,
+    cx: &mut Context<'_>,
     render_mode: RenderMode,
 ) {
-    let header = meth.fn_header(cx.tcx()).expect("Trying to get header from a non-function item");
+    let tcx = cx.tcx();
+    let header = meth.fn_header(tcx).expect("Trying to get header from a non-function item");
     let name = meth.name.as_ref().unwrap();
-    let vis = meth.visibility.print_with_space(meth.item_id, cx).to_string();
+    let vis = visibility_print_with_space(meth.visibility(tcx), meth.item_id, cx).to_string();
     // FIXME: Once https://github.com/rust-lang/rust/issues/67792 is implemented, we can remove
     // this condition.
     let constness = match render_mode {
         RenderMode::Normal => {
-            print_constness_with_space(&header.constness, meth.const_stability(cx.tcx()))
+            print_constness_with_space(&header.constness, meth.const_stability(tcx))
         }
         RenderMode::ForDeref { .. } => "",
     };
@@ -834,6 +836,8 @@ fn assoc_method(
         + name.as_str().len()
         + generics_len;
 
+    let notable_traits = d.output.as_return().and_then(|output| notable_traits_button(output, cx));
+
     let (indent, indent_str, end_newline) = if parent == ItemType::Trait {
         header_len += 4;
         let indent_str = "    ";
@@ -859,9 +863,9 @@ fn assoc_method(
         name = name,
         generics = g.print(cx),
         decl = d.full_print(header_len, indent, cx),
-        notable_traits = notable_traits_decl(d, cx),
+        notable_traits = notable_traits.unwrap_or_default(),
         where_clause = print_where_clause(g, cx, indent, end_newline),
-    )
+    );
 }
 
 /// Writes a span containing the versions at which an item became stable and/or const-stable. For
@@ -961,7 +965,7 @@ fn render_assoc_item(
     item: &clean::Item,
     link: AssocItemLink<'_>,
     parent: ItemType,
-    cx: &Context<'_>,
+    cx: &mut Context<'_>,
     render_mode: RenderMode,
 ) {
     match &*item.kind {
@@ -1271,79 +1275,133 @@ fn should_render_item(item: &clean::Item, deref_mut_: bool, tcx: TyCtxt<'_>) ->
     }
 }
 
-fn notable_traits_decl(decl: &clean::FnDecl, cx: &Context<'_>) -> String {
-    let mut out = Buffer::html();
+pub(crate) fn notable_traits_button(ty: &clean::Type, cx: &mut Context<'_>) -> Option<String> {
+    let mut has_notable_trait = false;
 
-    if let Some((did, ty)) = decl.output.as_return().and_then(|t| Some((t.def_id(cx.cache())?, t)))
+    let did = ty.def_id(cx.cache())?;
+
+    // Box has pass-through impls for Read, Write, Iterator, and Future when the
+    // boxed type implements one of those. We don't want to treat every Box return
+    // as being notably an Iterator (etc), though, so we exempt it. Pin has the same
+    // issue, with a pass-through impl for Future.
+    if Some(did) == cx.tcx().lang_items().owned_box()
+        || Some(did) == cx.tcx().lang_items().pin_type()
     {
-        if let Some(impls) = cx.cache().impls.get(&did) {
-            for i in impls {
-                let impl_ = i.inner_impl();
-                if !impl_.for_.without_borrowed_ref().is_same(ty.without_borrowed_ref(), cx.cache())
+        return None;
+    }
+
+    if let Some(impls) = cx.cache().impls.get(&did) {
+        for i in impls {
+            let impl_ = i.inner_impl();
+            if !impl_.for_.without_borrowed_ref().is_same(ty.without_borrowed_ref(), cx.cache()) {
+                // Two different types might have the same did,
+                // without actually being the same.
+                continue;
+            }
+            if let Some(trait_) = &impl_.trait_ {
+                let trait_did = trait_.def_id();
+
+                if cx.cache().traits.get(&trait_did).map_or(false, |t| t.is_notable_trait(cx.tcx()))
                 {
-                    // Two different types might have the same did,
-                    // without actually being the same.
-                    continue;
-                }
-                if let Some(trait_) = &impl_.trait_ {
-                    let trait_did = trait_.def_id();
-
-                    if cx
-                        .cache()
-                        .traits
-                        .get(&trait_did)
-                        .map_or(false, |t| t.is_notable_trait(cx.tcx()))
-                    {
-                        if out.is_empty() {
-                            write!(
-                                &mut out,
-                                "<span class=\"notable\">Notable traits for {}</span>\
-                             <code class=\"content\">",
-                                impl_.for_.print(cx)
-                            );
-                        }
-
-                        //use the "where" class here to make it small
-                        write!(
-                            &mut out,
-                            "<span class=\"where fmt-newline\">{}</span>",
-                            impl_.print(false, cx)
-                        );
-                        for it in &impl_.items {
-                            if let clean::AssocTypeItem(ref tydef, ref _bounds) = *it.kind {
-                                out.push_str("<span class=\"where fmt-newline\">    ");
-                                let empty_set = FxHashSet::default();
-                                let src_link =
-                                    AssocItemLink::GotoSource(trait_did.into(), &empty_set);
-                                assoc_type(
-                                    &mut out,
-                                    it,
-                                    &tydef.generics,
-                                    &[], // intentionally leaving out bounds
-                                    Some(&tydef.type_),
-                                    src_link,
-                                    0,
-                                    cx,
-                                );
-                                out.push_str(";</span>");
-                            }
-                        }
-                    }
+                    has_notable_trait = true;
                 }
             }
         }
     }
 
-    if !out.is_empty() {
-        out.insert_str(
-            0,
-            "<span class=\"notable-traits\"><span class=\"notable-traits-tooltip\">ⓘ\
-            <span class=\"notable-traits-tooltiptext\"><span class=\"docblock\">",
-        );
-        out.push_str("</code></span></span></span></span>");
+    if has_notable_trait {
+        cx.types_with_notable_traits.insert(ty.clone());
+        Some(format!(
+            " <a href=\"#\" class=\"notable-traits\" data-ty=\"{ty}\">ⓘ</a>",
+            ty = Escape(&format!("{:#}", ty.print(cx))),
+        ))
+    } else {
+        None
+    }
+}
+
+fn notable_traits_decl(ty: &clean::Type, cx: &Context<'_>) -> (String, String) {
+    let mut out = Buffer::html();
+
+    let did = ty.def_id(cx.cache()).expect("notable_traits_button already checked this");
+
+    let impls = cx.cache().impls.get(&did).expect("notable_traits_button already checked this");
+
+    for i in impls {
+        let impl_ = i.inner_impl();
+        if !impl_.for_.without_borrowed_ref().is_same(ty.without_borrowed_ref(), cx.cache()) {
+            // Two different types might have the same did,
+            // without actually being the same.
+            continue;
+        }
+        if let Some(trait_) = &impl_.trait_ {
+            let trait_did = trait_.def_id();
+
+            if cx.cache().traits.get(&trait_did).map_or(false, |t| t.is_notable_trait(cx.tcx())) {
+                if out.is_empty() {
+                    write!(
+                        &mut out,
+                        "<h3>Notable traits for <code>{}</code></h3>\
+                     <pre class=\"content\"><code>",
+                        impl_.for_.print(cx)
+                    );
+                }
+
+                //use the "where" class here to make it small
+                write!(
+                    &mut out,
+                    "<span class=\"where fmt-newline\">{}</span>",
+                    impl_.print(false, cx)
+                );
+                for it in &impl_.items {
+                    if let clean::AssocTypeItem(ref tydef, ref _bounds) = *it.kind {
+                        out.push_str("<span class=\"where fmt-newline\">    ");
+                        let empty_set = FxHashSet::default();
+                        let src_link = AssocItemLink::GotoSource(trait_did.into(), &empty_set);
+                        assoc_type(
+                            &mut out,
+                            it,
+                            &tydef.generics,
+                            &[], // intentionally leaving out bounds
+                            Some(&tydef.type_),
+                            src_link,
+                            0,
+                            cx,
+                        );
+                        out.push_str(";</span>");
+                    }
+                }
+            }
+        }
+    }
+    if out.is_empty() {
+        write!(&mut out, "</code></pre>",);
     }
 
-    out.into_inner()
+    (format!("{:#}", ty.print(cx)), out.into_inner())
+}
+
+pub(crate) fn notable_traits_json<'a>(
+    tys: impl Iterator<Item = &'a clean::Type>,
+    cx: &Context<'_>,
+) -> String {
+    let mut mp: Vec<(String, String)> = tys.map(|ty| notable_traits_decl(ty, cx)).collect();
+    mp.sort_by(|(name1, _html1), (name2, _html2)| name1.cmp(name2));
+    struct NotableTraitsMap(Vec<(String, String)>);
+    impl Serialize for NotableTraitsMap {
+        fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+        where
+            S: Serializer,
+        {
+            let mut map = serializer.serialize_map(Some(self.0.len()))?;
+            for item in &self.0 {
+                map.serialize_entry(&item.0, &item.1)?;
+            }
+            map.end()
+        }
+    }
+    serde_json::to_string(&NotableTraitsMap(mp))
+        .expect("serialize (string, string) -> json object cannot fail")
 }
 
 #[derive(Clone, Copy, Debug)]
@@ -2860,10 +2918,6 @@ fn render_call_locations(w: &mut Buffer, cx: &mut Context<'_>, item: &clean::Ite
             write!(w, r#"<span class="prev">&pr;</span> <span class="next">&sc;</span>"#);
         }
 
-        if needs_expansion {
-            write!(w, r#"<span class="expand">&varr;</span>"#);
-        }
-
         // Look for the example file in the source map if it exists, otherwise return a dummy span
         let file_span = (|| {
             let source_map = tcx.sess.source_map();
@@ -2883,9 +2937,6 @@ fn render_call_locations(w: &mut Buffer, cx: &mut Context<'_>, item: &clean::Ite
         })()
         .unwrap_or(rustc_span::DUMMY_SP);
 
-        // The root path is the inverse of Context::current
-        let root_path = vec!["../"; cx.current.len() - 1].join("");
-
         let mut decoration_info = FxHashMap::default();
         decoration_info.insert("highlight focus", vec![byte_ranges.remove(0)]);
         decoration_info.insert("highlight", byte_ranges);
@@ -2895,9 +2946,9 @@ fn render_call_locations(w: &mut Buffer, cx: &mut Context<'_>, item: &clean::Ite
             contents_subset,
             file_span,
             cx,
-            &root_path,
+            &cx.root_path(),
             highlight::DecorationInfo(decoration_info),
-            sources::SourceContext::Embedded { offset: line_min },
+            sources::SourceContext::Embedded { offset: line_min, needs_expansion },
         );
         write!(w, "</div></div>");
 
diff --git a/src/librustdoc/html/render/print_item.rs b/src/librustdoc/html/render/print_item.rs
index 6327817364a5..ac11a860a4f0 100644
--- a/src/librustdoc/html/render/print_item.rs
+++ b/src/librustdoc/html/render/print_item.rs
@@ -7,7 +7,7 @@ use rustc_hir::def_id::DefId;
 use rustc_middle::middle::stability;
 use rustc_middle::span_bug;
 use rustc_middle::ty::layout::LayoutError;
-use rustc_middle::ty::{Adt, TyCtxt};
+use rustc_middle::ty::{self, Adt, TyCtxt};
 use rustc_span::hygiene::MacroKind;
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_target::abi::{Layout, Primitive, TagEncoding, Variants};
@@ -17,9 +17,10 @@ use std::rc::Rc;
 
 use super::{
     collect_paths_for_type, document, ensure_trailing_slash, get_filtered_impls_for_reference,
-    item_ty_to_section, notable_traits_decl, render_all_impls, render_assoc_item,
-    render_assoc_items, render_attributes_in_code, render_attributes_in_pre, render_impl,
-    render_rightside, render_stability_since_raw, AssocItemLink, Context, ImplRenderingParameters,
+    item_ty_to_section, notable_traits_button, notable_traits_json, render_all_impls,
+    render_assoc_item, render_assoc_items, render_attributes_in_code, render_attributes_in_pre,
+    render_impl, render_rightside, render_stability_since_raw, AssocItemLink, Context,
+    ImplRenderingParameters,
 };
 use crate::clean;
 use crate::config::ModuleSorting;
@@ -28,12 +29,12 @@ use crate::formats::{AssocItemRender, Impl, RenderMode};
 use crate::html::escape::Escape;
 use crate::html::format::{
     join_with_double_colon, print_abi_with_space, print_constness_with_space, print_where_clause,
-    Buffer, Ending, PrintWithSpace,
+    visibility_print_with_space, Buffer, Ending, PrintWithSpace,
 };
-use crate::html::highlight;
 use crate::html::layout::Page;
 use crate::html::markdown::{HeadingOffset, MarkdownSummaryLine};
 use crate::html::url_parts_builder::UrlPartsBuilder;
+use crate::html::{highlight, static_files};
 
 use askama::Template;
 use itertools::Itertools;
@@ -52,8 +53,8 @@ struct PathComponent {
 #[derive(Template)]
 #[template(path = "print_item.html")]
 struct ItemVars<'a> {
-    page: &'a Page<'a>,
     static_root_path: &'a str,
+    clipboard_svg: &'static static_files::StaticFile,
     typ: &'a str,
     name: &'a str,
     item_type: &'a str,
@@ -147,8 +148,8 @@ pub(super) fn print_item(
     };
 
     let item_vars = ItemVars {
-        page,
-        static_root_path: page.get_static_root_path(),
+        static_root_path: &page.get_static_root_path(),
+        clipboard_svg: &static_files::STATIC_FILES.clipboard_svg,
         typ,
         name: item.name.as_ref().unwrap().as_str(),
         item_type: &item.type_().to_string(),
@@ -183,6 +184,16 @@ pub(super) fn print_item(
             unreachable!();
         }
     }
+
+    // Render notable-traits.js used for all methods in this module.
+    if !cx.types_with_notable_traits.is_empty() {
+        write!(
+            buf,
+            r#"<script type="text/json" id="notable-traits-data">{}</script>"#,
+            notable_traits_json(cx.types_with_notable_traits.iter(), cx)
+        );
+        cx.types_with_notable_traits.clear();
+    }
 }
 
 /// For large structs, enums, unions, etc, determine whether to hide their fields
@@ -318,6 +329,7 @@ fn item_module(w: &mut Buffer, cx: &mut Context<'_>, item: &clean::Item, items:
             );
         }
 
+        let tcx = cx.tcx();
         match *myitem.kind {
             clean::ExternCrateItem { ref src } => {
                 use crate::html::format::anchor;
@@ -327,14 +339,14 @@ fn item_module(w: &mut Buffer, cx: &mut Context<'_>, item: &clean::Item, items:
                     Some(src) => write!(
                         w,
                         "<div class=\"item-left\"><code>{}extern crate {} as {};",
-                        myitem.visibility.print_with_space(myitem.item_id, cx),
+                        visibility_print_with_space(myitem.visibility(tcx), myitem.item_id, cx),
                         anchor(myitem.item_id.expect_def_id(), src, cx),
                         myitem.name.unwrap(),
                     ),
                     None => write!(
                         w,
                         "<div class=\"item-left\"><code>{}extern crate {};",
-                        myitem.visibility.print_with_space(myitem.item_id, cx),
+                        visibility_print_with_space(myitem.visibility(tcx), myitem.item_id, cx),
                         anchor(myitem.item_id.expect_def_id(), myitem.name.unwrap(), cx),
                     ),
                 }
@@ -384,7 +396,7 @@ fn item_module(w: &mut Buffer, cx: &mut Context<'_>, item: &clean::Item, items:
                      </div>\
                      {stab_tags_before}{stab_tags}{stab_tags_after}",
                     stab = stab.unwrap_or_default(),
-                    vis = myitem.visibility.print_with_space(myitem.item_id, cx),
+                    vis = visibility_print_with_space(myitem.visibility(tcx), myitem.item_id, cx),
                     imp = import.print(cx),
                 );
                 w.write_str(ITEM_TABLE_ROW_CLOSE);
@@ -408,8 +420,8 @@ fn item_module(w: &mut Buffer, cx: &mut Context<'_>, item: &clean::Item, items:
                 let stab = myitem.stability_class(cx.tcx());
                 let add = if stab.is_some() { " " } else { "" };
 
-                let visibility_emoji = match myitem.visibility {
-                    clean::Visibility::Restricted(_) => {
+                let visibility_emoji = match myitem.visibility(tcx) {
+                    Some(ty::Visibility::Restricted(_)) => {
                         "<span title=\"Restricted Visibility\">&nbsp;🔒</span> "
                     }
                     _ => "",
@@ -496,12 +508,13 @@ fn extra_info_tags(item: &clean::Item, parent: &clean::Item, tcx: TyCtxt<'_>) ->
 }
 
 fn item_function(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, f: &clean::Function) {
-    let header = it.fn_header(cx.tcx()).expect("printing a function which isn't a function");
-    let constness = print_constness_with_space(&header.constness, it.const_stability(cx.tcx()));
+    let tcx = cx.tcx();
+    let header = it.fn_header(tcx).expect("printing a function which isn't a function");
+    let constness = print_constness_with_space(&header.constness, it.const_stability(tcx));
     let unsafety = header.unsafety.print_with_space();
     let abi = print_abi_with_space(header.abi).to_string();
     let asyncness = header.asyncness.print_with_space();
-    let visibility = it.visibility.print_with_space(it.item_id, cx).to_string();
+    let visibility = visibility_print_with_space(it.visibility(tcx), it.item_id, cx).to_string();
     let name = it.name.unwrap();
 
     let generics_len = format!("{:#}", f.generics.print(cx)).len();
@@ -514,6 +527,9 @@ fn item_function(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, f: &cle
         + name.as_str().len()
         + generics_len;
 
+    let notable_traits =
+        f.decl.output.as_return().and_then(|output| notable_traits_button(output, cx));
+
     wrap_into_item_decl(w, |w| {
         wrap_item(w, "fn", |w| {
             render_attributes_in_pre(w, it, "");
@@ -531,14 +547,15 @@ fn item_function(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, f: &cle
                 generics = f.generics.print(cx),
                 where_clause = print_where_clause(&f.generics, cx, 0, Ending::Newline),
                 decl = f.decl.full_print(header_len, 0, cx),
-                notable_traits = notable_traits_decl(&f.decl, cx),
+                notable_traits = notable_traits.unwrap_or_default(),
             );
         });
     });
-    document(w, cx, it, None, HeadingOffset::H2)
+    document(w, cx, it, None, HeadingOffset::H2);
 }
 
 fn item_trait(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, t: &clean::Trait) {
+    let tcx = cx.tcx();
     let bounds = bounds(&t.bounds, false, cx);
     let required_types = t.items.iter().filter(|m| m.is_ty_associated_type()).collect::<Vec<_>>();
     let provided_types = t.items.iter().filter(|m| m.is_associated_type()).collect::<Vec<_>>();
@@ -549,8 +566,7 @@ fn item_trait(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, t: &clean:
     let count_types = required_types.len() + provided_types.len();
     let count_consts = required_consts.len() + provided_consts.len();
     let count_methods = required_methods.len() + provided_methods.len();
-    let must_implement_one_of_functions =
-        cx.tcx().trait_def(t.def_id).must_implement_one_of.clone();
+    let must_implement_one_of_functions = tcx.trait_def(t.def_id).must_implement_one_of.clone();
 
     // Output the trait definition
     wrap_into_item_decl(w, |w| {
@@ -559,9 +575,9 @@ fn item_trait(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, t: &clean:
             write!(
                 w,
                 "{}{}{}trait {}{}{}",
-                it.visibility.print_with_space(it.item_id, cx),
-                t.unsafety(cx.tcx()).print_with_space(),
-                if t.is_auto(cx.tcx()) { "auto " } else { "" },
+                visibility_print_with_space(it.visibility(tcx), it.item_id, cx),
+                t.unsafety(tcx).print_with_space(),
+                if t.is_auto(tcx) { "auto " } else { "" },
                 it.name.unwrap(),
                 t.generics.print(cx),
                 bounds
@@ -1020,7 +1036,7 @@ fn item_trait(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, t: &clean:
     }
     let extern_crates = extern_crates
         .into_iter()
-        .map(|cnum| cx.shared.tcx.crate_name(cnum).to_string())
+        .map(|cnum| tcx.crate_name(cnum).to_string())
         .collect::<Vec<_>>()
         .join(",");
     let (extern_before, extern_after) =
@@ -1084,7 +1100,7 @@ fn item_typedef(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, t: &clea
     fn write_content(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, t: &clean::Typedef) {
         wrap_item(w, "typedef", |w| {
             render_attributes_in_pre(w, it, "");
-            write!(w, "{}", it.visibility.print_with_space(it.item_id, cx));
+            write!(w, "{}", visibility_print_with_space(it.visibility(cx.tcx()), it.item_id, cx));
             write!(
                 w,
                 "type {}{}{where_clause} = {type_};",
@@ -1173,6 +1189,7 @@ fn print_tuple_struct_fields(w: &mut Buffer, cx: &Context<'_>, s: &[clean::Item]
 }
 
 fn item_enum(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, e: &clean::Enum) {
+    let tcx = cx.tcx();
     let count_variants = e.variants().count();
     wrap_into_item_decl(w, |w| {
         wrap_item(w, "enum", |w| {
@@ -1180,7 +1197,7 @@ fn item_enum(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, e: &clean::
             write!(
                 w,
                 "{}enum {}{}",
-                it.visibility.print_with_space(it.item_id, cx),
+                visibility_print_with_space(it.visibility(tcx), it.item_id, cx),
                 it.name.unwrap(),
                 e.generics.print(cx),
             );
@@ -1268,10 +1285,10 @@ fn item_enum(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, e: &clean::
             w.write_str("</code>");
             render_stability_since_raw(
                 w,
-                variant.stable_since(cx.tcx()),
-                variant.const_stability(cx.tcx()),
-                it.stable_since(cx.tcx()),
-                it.const_stable_since(cx.tcx()),
+                variant.stable_since(tcx),
+                variant.const_stability(tcx),
+                it.stable_since(tcx),
+                it.const_stable_since(tcx),
             );
             w.write_str("</h3>");
 
@@ -1389,12 +1406,13 @@ fn item_primitive(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item) {
 fn item_constant(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, c: &clean::Constant) {
     wrap_into_item_decl(w, |w| {
         wrap_item(w, "const", |w| {
+            let tcx = cx.tcx();
             render_attributes_in_code(w, it);
 
             write!(
                 w,
                 "{vis}const {name}: {typ}",
-                vis = it.visibility.print_with_space(it.item_id, cx),
+                vis = visibility_print_with_space(it.visibility(tcx), it.item_id, cx),
                 name = it.name.unwrap(),
                 typ = c.type_.print(cx),
             );
@@ -1408,9 +1426,9 @@ fn item_constant(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, c: &cle
             //            ` = 100i32;`
             //        instead?
 
-            let value = c.value(cx.tcx());
-            let is_literal = c.is_literal(cx.tcx());
-            let expr = c.expr(cx.tcx());
+            let value = c.value(tcx);
+            let is_literal = c.is_literal(tcx);
+            let expr = c.expr(tcx);
             if value.is_some() || is_literal {
                 write!(w, " = {expr};", expr = Escape(&expr));
             } else {
@@ -1495,7 +1513,7 @@ fn item_static(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item, s: &clean
             write!(
                 w,
                 "{vis}static {mutability}{name}: {typ}",
-                vis = it.visibility.print_with_space(it.item_id, cx),
+                vis = visibility_print_with_space(it.visibility(cx.tcx()), it.item_id, cx),
                 mutability = s.mutability.print_with_space(),
                 name = it.name.unwrap(),
                 typ = s.type_.print(cx)
@@ -1513,7 +1531,7 @@ fn item_foreign_type(w: &mut Buffer, cx: &mut Context<'_>, it: &clean::Item) {
             write!(
                 w,
                 "    {}type {};\n}}",
-                it.visibility.print_with_space(it.item_id, cx),
+                visibility_print_with_space(it.visibility(cx.tcx()), it.item_id, cx),
                 it.name.unwrap(),
             );
         });
@@ -1666,7 +1684,13 @@ fn render_union(
     tab: &str,
     cx: &Context<'_>,
 ) {
-    write!(w, "{}union {}", it.visibility.print_with_space(it.item_id, cx), it.name.unwrap(),);
+    let tcx = cx.tcx();
+    write!(
+        w,
+        "{}union {}",
+        visibility_print_with_space(it.visibility(tcx), it.item_id, cx),
+        it.name.unwrap(),
+    );
 
     let where_displayed = g
         .map(|g| {
@@ -1693,7 +1717,7 @@ fn render_union(
             write!(
                 w,
                 "    {}{}: {},\n{}",
-                field.visibility.print_with_space(field.item_id, cx),
+                visibility_print_with_space(field.visibility(tcx), field.item_id, cx),
                 field.name.unwrap(),
                 ty.print(cx),
                 tab
@@ -1720,10 +1744,11 @@ fn render_struct(
     structhead: bool,
     cx: &Context<'_>,
 ) {
+    let tcx = cx.tcx();
     write!(
         w,
         "{}{}{}",
-        it.visibility.print_with_space(it.item_id, cx),
+        visibility_print_with_space(it.visibility(tcx), it.item_id, cx),
         if structhead { "struct " } else { "" },
         it.name.unwrap()
     );
@@ -1753,7 +1778,7 @@ fn render_struct(
                         w,
                         "\n{}    {}{}: {},",
                         tab,
-                        field.visibility.print_with_space(field.item_id, cx),
+                        visibility_print_with_space(field.visibility(tcx), field.item_id, cx),
                         field.name.unwrap(),
                         ty.print(cx),
                     );
@@ -1785,7 +1810,7 @@ fn render_struct(
                         write!(
                             w,
                             "{}{}",
-                            field.visibility.print_with_space(field.item_id, cx),
+                            visibility_print_with_space(field.visibility(tcx), field.item_id, cx),
                             ty.print(cx),
                         )
                     }
diff --git a/src/librustdoc/html/render/write_shared.rs b/src/librustdoc/html/render/write_shared.rs
index 85f63c985b37..94d8a9feca69 100644
--- a/src/librustdoc/html/render/write_shared.rs
+++ b/src/librustdoc/html/render/write_shared.rs
@@ -1,10 +1,8 @@
-use std::ffi::OsStr;
 use std::fs::{self, File};
 use std::io::prelude::*;
 use std::io::{self, BufReader};
-use std::path::{Component, Path, PathBuf};
+use std::path::{Component, Path};
 use std::rc::Rc;
-use std::sync::LazyLock as Lazy;
 
 use itertools::Itertools;
 use rustc_data_structures::flock;
@@ -20,123 +18,20 @@ use crate::error::Error;
 use crate::html::{layout, static_files};
 use crate::{try_err, try_none};
 
-static FILES_UNVERSIONED: Lazy<FxHashMap<&str, &[u8]>> = Lazy::new(|| {
-    map! {
-        "FiraSans-Regular.woff2" => static_files::fira_sans::REGULAR,
-        "FiraSans-Medium.woff2" => static_files::fira_sans::MEDIUM,
-        "FiraSans-LICENSE.txt" => static_files::fira_sans::LICENSE,
-        "SourceSerif4-Regular.ttf.woff2" => static_files::source_serif_4::REGULAR,
-        "SourceSerif4-Bold.ttf.woff2" => static_files::source_serif_4::BOLD,
-        "SourceSerif4-It.ttf.woff2" => static_files::source_serif_4::ITALIC,
-        "SourceSerif4-LICENSE.md" => static_files::source_serif_4::LICENSE,
-        "SourceCodePro-Regular.ttf.woff2" => static_files::source_code_pro::REGULAR,
-        "SourceCodePro-Semibold.ttf.woff2" => static_files::source_code_pro::SEMIBOLD,
-        "SourceCodePro-It.ttf.woff2" => static_files::source_code_pro::ITALIC,
-        "SourceCodePro-LICENSE.txt" => static_files::source_code_pro::LICENSE,
-        "NanumBarunGothic.ttf.woff2" => static_files::nanum_barun_gothic::REGULAR,
-        "NanumBarunGothic-LICENSE.txt" => static_files::nanum_barun_gothic::LICENSE,
-        "LICENSE-MIT.txt" => static_files::LICENSE_MIT,
-        "LICENSE-APACHE.txt" => static_files::LICENSE_APACHE,
-        "COPYRIGHT.txt" => static_files::COPYRIGHT,
-    }
-});
-
-enum SharedResource<'a> {
-    /// This file will never change, no matter what toolchain is used to build it.
-    ///
-    /// It does not have a resource suffix.
-    Unversioned { name: &'static str },
-    /// This file may change depending on the toolchain.
-    ///
-    /// It has a resource suffix.
-    ToolchainSpecific { basename: &'static str },
-    /// This file may change for any crate within a build, or based on the CLI arguments.
-    ///
-    /// This differs from normal invocation-specific files because it has a resource suffix.
-    InvocationSpecific { basename: &'a str },
-}
-
-impl SharedResource<'_> {
-    fn extension(&self) -> Option<&OsStr> {
-        use SharedResource::*;
-        match self {
-            Unversioned { name }
-            | ToolchainSpecific { basename: name }
-            | InvocationSpecific { basename: name } => Path::new(name).extension(),
-        }
-    }
-
-    fn path(&self, cx: &Context<'_>) -> PathBuf {
-        match self {
-            SharedResource::Unversioned { name } => cx.dst.join(name),
-            SharedResource::ToolchainSpecific { basename } => cx.suffix_path(basename),
-            SharedResource::InvocationSpecific { basename } => cx.suffix_path(basename),
-        }
-    }
-
-    fn should_emit(&self, emit: &[EmitType]) -> bool {
-        if emit.is_empty() {
-            return true;
-        }
-        let kind = match self {
-            SharedResource::Unversioned { .. } => EmitType::Unversioned,
-            SharedResource::ToolchainSpecific { .. } => EmitType::Toolchain,
-            SharedResource::InvocationSpecific { .. } => EmitType::InvocationSpecific,
-        };
-        emit.contains(&kind)
-    }
-}
-
-impl Context<'_> {
-    fn suffix_path(&self, filename: &str) -> PathBuf {
-        // We use splitn vs Path::extension here because we might get a filename
-        // like `style.min.css` and we want to process that into
-        // `style-suffix.min.css`.  Path::extension would just return `css`
-        // which would result in `style.min-suffix.css` which isn't what we
-        // want.
-        let (base, ext) = filename.split_once('.').unwrap();
-        let filename = format!("{}{}.{}", base, self.shared.resource_suffix, ext);
-        self.dst.join(&filename)
-    }
-
-    fn write_shared(
-        &self,
-        resource: SharedResource<'_>,
-        contents: impl 'static + Send + AsRef<[u8]>,
-        emit: &[EmitType],
-    ) -> Result<(), Error> {
-        if resource.should_emit(emit) {
-            self.shared.fs.write(resource.path(self), contents)
-        } else {
-            Ok(())
-        }
-    }
-
-    fn write_minify(
-        &self,
-        resource: SharedResource<'_>,
-        contents: impl 'static + Send + AsRef<str> + AsRef<[u8]>,
-        minify: bool,
-        emit: &[EmitType],
-    ) -> Result<(), Error> {
-        if minify {
-            let contents = contents.as_ref();
-            let contents = if resource.extension() == Some(OsStr::new("css")) {
-                minifier::css::minify(contents)
-                    .map_err(|e| {
-                        Error::new(format!("failed to minify CSS file: {}", e), resource.path(self))
-                    })?
-                    .to_string()
-            } else {
-                minifier::js::minify(contents).to_string()
-            };
-            self.write_shared(resource, contents, emit)
-        } else {
-            self.write_shared(resource, contents, emit)
-        }
-    }
-}
-
+/// Rustdoc writes out two kinds of shared files:
+///  - Static files, which are embedded in the rustdoc binary and are written with a
+///    filename that includes a hash of their contents. These will always have a new
+///    URL if the contents change, so they are safe to cache with the
+///    `Cache-Control: immutable` directive. They are written under the static.files/
+///    directory and are written when --emit-type is empty (default) or contains
+///    "toolchain-specific". If using the --static-root-path flag, it should point
+///    to a URL path prefix where each of these filenames can be fetched.
+///  - Invocation specific files. These are generated based on the crate(s) being
+///    documented. Their filenames need to be predictable without knowing their
+///    contents, so they do not include a hash in their filename and are not safe to
+///    cache with `Cache-Control: immutable`. They include the contents of the
+///    --resource-suffix flag and are emitted when --emit-type is empty (default)
+///    or contains "invocation-specific".
 pub(super) fn write_shared(
     cx: &mut Context<'_>,
     krate: &Crate,
@@ -149,139 +44,52 @@ pub(super) fn write_shared(
     let lock_file = cx.dst.join(".lock");
     let _lock = try_err!(flock::Lock::new(&lock_file, true, true, true), &lock_file);
 
-    // Minified resources are usually toolchain resources. If they're not, they should use `cx.write_minify` directly.
-    fn write_minify(
-        basename: &'static str,
-        contents: impl 'static + Send + AsRef<str> + AsRef<[u8]>,
-        cx: &Context<'_>,
-        options: &RenderOptions,
-    ) -> Result<(), Error> {
-        cx.write_minify(
-            SharedResource::ToolchainSpecific { basename },
-            contents,
-            options.enable_minification,
-            &options.emit,
-        )
-    }
-
-    // Toolchain resources should never be dynamic.
-    let write_toolchain = |p: &'static _, c: &'static _| {
-        cx.write_shared(SharedResource::ToolchainSpecific { basename: p }, c, &options.emit)
-    };
-
-    // Crate resources should always be dynamic.
-    let write_crate = |p: &_, make_content: &dyn Fn() -> Result<Vec<u8>, Error>| {
+    // InvocationSpecific resources should always be dynamic.
+    let write_invocation_specific = |p: &str, make_content: &dyn Fn() -> Result<Vec<u8>, Error>| {
         let content = make_content()?;
-        cx.write_shared(SharedResource::InvocationSpecific { basename: p }, content, &options.emit)
+        if options.emit.is_empty() || options.emit.contains(&EmitType::InvocationSpecific) {
+            let output_filename = static_files::suffix_path(p, &cx.shared.resource_suffix);
+            cx.shared.fs.write(cx.dst.join(output_filename), content)
+        } else {
+            Ok(())
+        }
     };
 
-    // Given "foo.svg", return e.g. "url(\"foo1.58.0.svg\")"
-    fn ver_url(cx: &Context<'_>, basename: &'static str) -> String {
-        format!(
-            "url(\"{}\")",
-            SharedResource::ToolchainSpecific { basename }
-                .path(cx)
-                .file_name()
-                .unwrap()
-                .to_str()
-                .unwrap()
-        )
-    }
-
-    // We use the AUTOREPLACE mechanism to inject into our static JS and CSS certain
-    // values that are only known at doc build time. Since this mechanism is somewhat
-    // surprising when reading the code, please limit it to rustdoc.css.
-    write_minify(
-        "rustdoc.css",
-        static_files::RUSTDOC_CSS
-            .replace(
-                "/* AUTOREPLACE: */url(\"toggle-minus.svg\")",
-                &ver_url(cx, "toggle-minus.svg"),
-            )
-            .replace("/* AUTOREPLACE: */url(\"toggle-plus.svg\")", &ver_url(cx, "toggle-plus.svg"))
-            .replace("/* AUTOREPLACE: */url(\"down-arrow.svg\")", &ver_url(cx, "down-arrow.svg")),
-        cx,
-        options,
-    )?;
-
-    // Add all the static files. These may already exist, but we just
-    // overwrite them anyway to make sure that they're fresh and up-to-date.
-    write_minify("settings.css", static_files::SETTINGS_CSS, cx, options)?;
-    write_minify("noscript.css", static_files::NOSCRIPT_CSS, cx, options)?;
-
-    // To avoid "light.css" to be overwritten, we'll first run over the received themes and only
-    // then we'll run over the "official" styles.
-    let mut themes: FxHashSet<String> = FxHashSet::default();
+    cx.shared
+        .fs
+        .create_dir_all(cx.dst.join("static.files"))
+        .map_err(|e| PathError::new(e, "static.files"))?;
 
+    // Handle added third-party themes
     for entry in &cx.shared.style_files {
         let theme = entry.basename()?;
         let extension =
             try_none!(try_none!(entry.path.extension(), &entry.path).to_str(), &entry.path);
 
-        // Handle the official themes
-        match theme.as_str() {
-            "light" => write_minify("light.css", static_files::themes::LIGHT, cx, options)?,
-            "dark" => write_minify("dark.css", static_files::themes::DARK, cx, options)?,
-            "ayu" => write_minify("ayu.css", static_files::themes::AYU, cx, options)?,
-            _ => {
-                // Handle added third-party themes
-                let filename = format!("{}.{}", theme, extension);
-                write_crate(&filename, &|| Ok(try_err!(fs::read(&entry.path), &entry.path)))?;
-            }
-        };
+        // Skip the official themes. They are written below as part of STATIC_FILES_LIST.
+        if matches!(theme.as_str(), "light" | "dark" | "ayu") {
+            continue;
+        }
 
-        themes.insert(theme.to_owned());
-    }
-
-    if (*cx.shared).layout.logo.is_empty() {
-        write_toolchain("rust-logo.svg", static_files::RUST_LOGO_SVG)?;
-    }
-    if (*cx.shared).layout.favicon.is_empty() {
-        write_toolchain("favicon.svg", static_files::RUST_FAVICON_SVG)?;
-        write_toolchain("favicon-16x16.png", static_files::RUST_FAVICON_PNG_16)?;
-        write_toolchain("favicon-32x32.png", static_files::RUST_FAVICON_PNG_32)?;
-    }
-    write_toolchain("wheel.svg", static_files::WHEEL_SVG)?;
-    write_toolchain("clipboard.svg", static_files::CLIPBOARD_SVG)?;
-    write_toolchain("down-arrow.svg", static_files::DOWN_ARROW_SVG)?;
-    write_toolchain("toggle-minus.svg", static_files::TOGGLE_MINUS_PNG)?;
-    write_toolchain("toggle-plus.svg", static_files::TOGGLE_PLUS_PNG)?;
-
-    let mut themes: Vec<&String> = themes.iter().collect();
-    themes.sort();
-
-    write_minify("main.js", static_files::MAIN_JS, cx, options)?;
-    write_minify("search.js", static_files::SEARCH_JS, cx, options)?;
-    write_minify("settings.js", static_files::SETTINGS_JS, cx, options)?;
-
-    if cx.include_sources {
-        write_minify("source-script.js", static_files::sidebar::SOURCE_SCRIPT, cx, options)?;
-    }
-
-    write_minify("storage.js", static_files::STORAGE_JS, cx, options)?;
-
-    if cx.shared.layout.scrape_examples_extension {
-        cx.write_minify(
-            SharedResource::InvocationSpecific { basename: "scrape-examples.js" },
-            static_files::SCRAPE_EXAMPLES_JS,
-            options.enable_minification,
-            &options.emit,
-        )?;
+        let bytes = try_err!(fs::read(&entry.path), &entry.path);
+        let filename = format!("{}{}.{}", theme, cx.shared.resource_suffix, extension);
+        cx.shared.fs.write(cx.dst.join(filename), bytes)?;
     }
 
+    // When the user adds their own CSS files with --extend-css, we write that as an
+    // invocation-specific file (that is, with a resource suffix).
     if let Some(ref css) = cx.shared.layout.css_file_extension {
         let buffer = try_err!(fs::read_to_string(css), css);
-        // This varies based on the invocation, so it can't go through the write_minify wrapper.
-        cx.write_minify(
-            SharedResource::InvocationSpecific { basename: "theme.css" },
-            buffer,
-            options.enable_minification,
-            &options.emit,
-        )?;
+        let path = static_files::suffix_path("theme.css", &cx.shared.resource_suffix);
+        cx.shared.fs.write(cx.dst.join(path), buffer)?;
     }
-    write_minify("normalize.css", static_files::NORMALIZE_CSS, cx, options)?;
-    for (name, contents) in &*FILES_UNVERSIONED {
-        cx.write_shared(SharedResource::Unversioned { name }, contents, &options.emit)?;
+
+    if options.emit.is_empty() || options.emit.contains(&EmitType::Toolchain) {
+        let static_dir = cx.dst.join(Path::new("static.files"));
+        static_files::for_each(|f: &static_files::StaticFile| {
+            let filename = static_dir.join(f.output_filename());
+            cx.shared.fs.write(filename, f.minified())
+        })?;
     }
 
     /// Read a file and return all lines that match the `"{crate}":{data},` format,
@@ -463,7 +271,7 @@ pub(super) fn write_shared(
             v.push_str("\\\n}');\ncreateSourceSidebar();\n");
             Ok(v.into_bytes())
         };
-        write_crate("source-files.js", &make_sources)?;
+        write_invocation_specific("source-files.js", &make_sources)?;
     }
 
     // Update the search index and crate list.
@@ -477,7 +285,7 @@ pub(super) fn write_shared(
     // Sort the indexes by crate so the file will be generated identically even
     // with rustdoc running in parallel.
     all_indexes.sort();
-    write_crate("search-index.js", &|| {
+    write_invocation_specific("search-index.js", &|| {
         let mut v = String::from("var searchIndex = JSON.parse('{\\\n");
         v.push_str(&all_indexes.join(",\\\n"));
         v.push_str(
@@ -490,7 +298,7 @@ if (typeof exports !== 'undefined') {exports.searchIndex = searchIndex};
         Ok(v.into_bytes())
     })?;
 
-    write_crate("crates.js", &|| {
+    write_invocation_specific("crates.js", &|| {
         let krates = krates.iter().map(|k| format!("\"{}\"", k)).join(",");
         Ok(format!("window.ALL_CRATES = [{}];", krates).into_bytes())
     })?;
diff --git a/src/librustdoc/html/sources.rs b/src/librustdoc/html/sources.rs
index 7ab65bff3469..50135d601900 100644
--- a/src/librustdoc/html/sources.rs
+++ b/src/librustdoc/html/sources.rs
@@ -258,7 +258,7 @@ where
 
 pub(crate) enum SourceContext {
     Standalone,
-    Embedded { offset: usize },
+    Embedded { offset: usize, needs_expansion: bool },
 }
 
 /// Wrapper struct to render the source code of a file. This will do things like
@@ -274,28 +274,34 @@ pub(crate) fn print_src(
 ) {
     let lines = s.lines().count();
     let mut line_numbers = Buffer::empty_from(buf);
+    let extra;
     line_numbers.write_str("<pre class=\"src-line-numbers\">");
+    let current_href = &context
+        .href_from_span(clean::Span::new(file_span), false)
+        .expect("only local crates should have sources emitted");
     match source_context {
         SourceContext::Standalone => {
+            extra = None;
             for line in 1..=lines {
-                writeln!(line_numbers, "<span id=\"{0}\">{0}</span>", line)
+                writeln!(line_numbers, "<a href=\"#{line}\" id=\"{line}\">{line}</a>")
             }
         }
-        SourceContext::Embedded { offset } => {
-            for line in 1..=lines {
-                writeln!(line_numbers, "<span>{0}</span>", line + offset)
+        SourceContext::Embedded { offset, needs_expansion } => {
+            extra =
+                if needs_expansion { Some(r#"<span class="expand">&varr;</span>"#) } else { None };
+            for line_number in 1..=lines {
+                let line = line_number + offset;
+                writeln!(line_numbers, "<span>{line}</span>")
             }
         }
     }
     line_numbers.write_str("</pre>");
-    let current_href = &context
-        .href_from_span(clean::Span::new(file_span), false)
-        .expect("only local crates should have sources emitted");
     highlight::render_source_with_highlighting(
         s,
         buf,
         line_numbers,
         highlight::HrefContext { context, file_span, root_path, current_href },
         decoration_info,
+        extra,
     );
 }
diff --git a/src/librustdoc/html/static/css/noscript.css b/src/librustdoc/html/static/css/noscript.css
index 63b35f5d0df0..54e8b6561f34 100644
--- a/src/librustdoc/html/static/css/noscript.css
+++ b/src/librustdoc/html/static/css/noscript.css
@@ -18,3 +18,13 @@ nav.sub {
 	/* The search bar and related controls don't work without JS */
 	display: none;
 }
+
+.source .sidebar {
+	display: none;
+}
+
+.notable-traits {
+	/* layout requires javascript
+	    https://github.com/rust-lang/rust/issues/102576 */
+	display: none;
+}
diff --git a/src/librustdoc/html/static/css/rustdoc.css b/src/librustdoc/html/static/css/rustdoc.css
index 293c9787609b..d195c9cf6f9f 100644
--- a/src/librustdoc/html/static/css/rustdoc.css
+++ b/src/librustdoc/html/static/css/rustdoc.css
@@ -4,7 +4,7 @@
 	font-style: normal;
 	font-weight: 400;
 	src: local('Fira Sans'),
-		url("FiraSans-Regular.woff2") format("woff2");
+		url("FiraSans-Regular-018c141bf0843ffd.woff2") format("woff2");
 	font-display: swap;
 }
 @font-face {
@@ -12,7 +12,7 @@
 	font-style: normal;
 	font-weight: 500;
 	src: local('Fira Sans Medium'),
-		url("FiraSans-Medium.woff2") format("woff2");
+		url("FiraSans-Medium-8f9a781e4970d388.woff2") format("woff2");
 	font-display: swap;
 }
 
@@ -22,7 +22,7 @@
 	font-style: normal;
 	font-weight: 400;
 	src: local('Source Serif 4'),
-		url("SourceSerif4-Regular.ttf.woff2") format("woff2");
+		url("SourceSerif4-Regular-1f7d512b176f0f72.ttf.woff2") format("woff2");
 	font-display: swap;
 }
 @font-face {
@@ -30,7 +30,7 @@
 	font-style: italic;
 	font-weight: 400;
 	src: local('Source Serif 4 Italic'),
-		url("SourceSerif4-It.ttf.woff2") format("woff2");
+		url("SourceSerif4-It-d034fe4ef9d0fa00.ttf.woff2") format("woff2");
 	font-display: swap;
 }
 @font-face {
@@ -38,7 +38,7 @@
 	font-style: normal;
 	font-weight: 700;
 	src: local('Source Serif 4 Bold'),
-		url("SourceSerif4-Bold.ttf.woff2") format("woff2");
+		url("SourceSerif4-Bold-124a1ca42af929b6.ttf.woff2") format("woff2");
 	font-display: swap;
 }
 
@@ -49,28 +49,28 @@
 	font-weight: 400;
 	/* Avoid using locally installed font because bad versions are in circulation:
 	 * see https://github.com/rust-lang/rust/issues/24355 */
-	src: url("SourceCodePro-Regular.ttf.woff2") format("woff2");
+	src: url("SourceCodePro-Regular-562dcc5011b6de7d.ttf.woff2") format("woff2");
 	font-display: swap;
 }
 @font-face {
 	font-family: 'Source Code Pro';
 	font-style: italic;
 	font-weight: 400;
-	src: url("SourceCodePro-It.ttf.woff2") format("woff2");
+	src: url("SourceCodePro-It-1cc31594bf4f1f79.ttf.woff2") format("woff2");
 	font-display: swap;
 }
 @font-face {
 	font-family: 'Source Code Pro';
 	font-style: normal;
 	font-weight: 600;
-	src: url("SourceCodePro-Semibold.ttf.woff2") format("woff2");
+	src: url("SourceCodePro-Semibold-d899c5a5c4aeb14a.ttf.woff2") format("woff2");
 	font-display: swap;
 }
 
 /* Avoid using legacy CJK serif fonts in Windows like Batang. */
 @font-face {
 	font-family: 'NanumBarunGothic';
-	src: url("NanumBarunGothic.ttf.woff2") format("woff2");
+	src: url("NanumBarunGothic-0f09457c7a19b7c6.ttf.woff2") format("woff2");
 	font-display: swap;
 	unicode-range: U+AC00-D7AF, U+1100-11FF, U+3130-318F, U+A960-A97F, U+D7B0-D7FF;
 }
@@ -163,9 +163,6 @@ h1.fqn {
 	padding-bottom: 6px;
 	margin-bottom: 15px;
 }
-#toggle-all-docs {
-	text-decoration: none;
-}
 /* The only headings that get underlines are:
 	 Markdown-generated headings within the top-doc
 	 Rustdoc-generated h2 section headings (e.g. "Implementations", "Required Methods", etc)
@@ -209,7 +206,7 @@ ul.all-items {
 	font-family: "Fira Sans", Arial, NanumBarunGothic, sans-serif;
 }
 
-a#toggle-all-docs,
+#toggle-all-docs,
 a.anchor,
 .small-section-header a,
 #source-sidebar a,
@@ -292,10 +289,6 @@ p:last-child {
 	margin: 0;
 }
 
-summary {
-	outline: none;
-}
-
 /* Fix some style changes due to normalize.css 8 */
 
 button {
@@ -303,6 +296,16 @@ button {
 	padding: 1px 6px;
 }
 
+button#toggle-all-docs {
+	padding: 0;
+	background: none;
+	border: none;
+	cursor: pointer;
+	/* iOS button gradient: https://stackoverflow.com/q/5438567 */
+	-webkit-appearance: none;
+	opacity: 1;
+}
+
 /* end tweaks for normalize.css 8 */
 
 .rustdoc {
@@ -364,7 +367,8 @@ img {
 	overflow: visible;
 }
 
-.sub-logo-container {
+.sub-logo-container, .logo-container {
+	/* zero text boxes so that computed line height = image height exactly */
 	line-height: 0;
 }
 
@@ -374,6 +378,10 @@ img {
 	object-fit: contain;
 }
 
+.rust-logo {
+	filter: var(--rust-logo-filter);
+}
+
 .sidebar, .mobile-topbar, .sidebar-menu-toggle {
 	background-color: var(--sidebar-background-color);
 }
@@ -402,10 +410,6 @@ img {
 	overflow-y: hidden;
 }
 
-.rustdoc.source .sidebar .sidebar-logo {
-	display: none;
-}
-
 .source .sidebar, #sidebar-toggle, #source-sidebar {
 	background-color: var(--sidebar-background-color);
 }
@@ -466,10 +470,9 @@ img {
 }
 
 .sidebar .logo-container {
-	display: flex;
 	margin-top: 10px;
 	margin-bottom: 10px;
-	justify-content: center;
+	text-align: center;
 }
 
 .version {
@@ -501,9 +504,7 @@ ul.block, .block li {
 .sidebar h2 {
 	overflow-wrap: anywhere;
 	padding: 0;
-	margin: 0;
-	margin-top: 0.7rem;
-	margin-bottom: 0.7rem;
+	margin: 0.7rem 0;
 }
 
 .sidebar h3 {
@@ -538,7 +539,6 @@ ul.block, .block li {
 }
 
 .source .content pre.rust {
-	white-space: pre;
 	overflow: auto;
 	padding-left: 0;
 }
@@ -554,45 +554,45 @@ ul.block, .block li {
 	margin-bottom: 0px;
 }
 
-pre.example-line-numbers {
-	overflow: initial;
-	border: 1px solid;
-	padding: 13px 8px;
-	text-align: right;
-	border-top-left-radius: 5px;
-	border-bottom-left-radius: 5px;
-}
-
-.src-line-numbers {
-	text-align: right;
-}
-.rustdoc:not(.source) .example-wrap > pre:not(.example-line-numbers) {
-	width: 100%;
+.rustdoc .example-wrap > pre {
+	margin: 0;
+	flex-grow: 1;
 	overflow-x: auto;
 }
 
-.rustdoc:not(.source) .example-wrap > pre.src-line-numbers {
-	width: auto;
-	overflow-x: visible;
-}
-
-.rustdoc .example-wrap > pre {
-	margin: 0;
-}
-
-.search-loading {
-	text-align: center;
-}
-
-.content > .example-wrap pre.src-line-numbers {
-	position: relative;
+.rustdoc .example-wrap > pre.example-line-numbers,
+.rustdoc .example-wrap > pre.src-line-numbers {
+	flex-grow: 0;
+	overflow: initial;
+	text-align: right;
 	-webkit-user-select: none;
 	-moz-user-select: none;
 	-ms-user-select: none;
 	user-select: none;
 }
-.src-line-numbers span {
-	cursor: pointer;
+
+.example-line-numbers {
+	border: 1px solid;
+	padding: 13px 8px;
+	border-top-left-radius: 5px;
+	border-bottom-left-radius: 5px;
+	border-color: var(--example-line-numbers-border-color);
+}
+
+.src-line-numbers a, .src-line-numbers span {
+	color: var(--src-line-numbers-span-color);
+}
+.src-line-numbers :target {
+	background-color: transparent;
+	border-right: none;
+	padding-right: 0;
+}
+.src-line-numbers .line-highlighted {
+	background-color: var(--src-line-number-highlighted-background-color);
+}
+
+.search-loading {
+	text-align: center;
 }
 
 .docblock-short {
@@ -682,7 +682,6 @@ pre, .rustdoc.source .example-wrap {
 }
 
 #main-content > .item-info {
-	margin-top: 0;
 	margin-left: 0;
 }
 
@@ -693,13 +692,16 @@ nav.sub {
 	display: flex;
 	align-items: center;
 }
-nav.sub form {
+.search-form {
+	position: relative;
+	display: flex;
+	height: 34px;
 	flex-grow: 1;
 }
 .source nav.sub {
 	margin: 0 0 15px 0;
 }
-.source nav.sub form {
+.source .search-form {
 	margin-left: 32px;
 }
 
@@ -790,11 +792,6 @@ table,
 	padding-right: 1.25rem;
 }
 
-.search-container {
-	position: relative;
-	display: flex;
-	height: 34px;
-}
 .search-results-title {
 	margin-top: 0;
 	white-space: nowrap;
@@ -815,10 +812,8 @@ table,
 }
 #crate-search {
 	min-width: 115px;
-	padding: 0;
 	/* keep these two in sync with "@-moz-document url-prefix()" below */
-	padding-left: 4px;
-	padding-right: 23px;
+	padding: 0 23px 0 4px;
 	/* prevents the <select> from overflowing the containing div in case it's shrunk */
 	max-width: 100%;
 	/* contents can overflow because of max-width limit, then show ellipsis */
@@ -836,6 +831,9 @@ table,
 	line-height: 1.5;
 	font-weight: 500;
 }
+#crate-search:hover, #crate-search:focus {
+	border-color: var(--crate-search-hover-border);
+}
 /* cancel stylistic differences in padding in firefox
 for "appearance: none"-style (or equivalent) <select>s */
 @-moz-document url-prefix() {
@@ -859,8 +857,13 @@ so that we can apply CSS-filters to change the arrow color in themes */
 	background-repeat: no-repeat;
 	background-size: 20px;
 	background-position: calc(100% - 2px) 56%;
-	/* image is black color, themes should apply a "filter" property to change the color */
-	background-image: /* AUTOREPLACE: */url("down-arrow.svg");
+	/* image is black color */
+	background-image: url("down-arrow-927217e04c7463ac.svg");
+	/* changes the arrow image color */
+	filter: var(--crate-search-div-filter);
+}
+#crate-search-div:hover::after, #crate-search-div:focus-within::after {
+	filter: var(--crate-search-div-hover-filter);
 }
 #crate-search > option {
 	font-size: 1rem;
@@ -870,17 +873,12 @@ so that we can apply CSS-filters to change the arrow color in themes */
 	   -webkit-appearance: textfield for search inputs. That
 	   causes rounded corners and no border on iOS Safari. */
 	-webkit-appearance: none;
-	/* Override Normalize.css: we have margins and do
-	 not want to overflow - the `moz` attribute is necessary
-	 until Firefox 29, too early to drop at this point */
-	-moz-box-sizing: border-box !important;
-	box-sizing: border-box !important;
 	outline: none;
 	border: 1px solid var(--border-color);
 	border-radius: 2px;
 	padding: 8px;
 	font-size: 1rem;
-	width: 100%;
+	flex-grow: 1;
 	background-color: var(--button-background-color);
 	color: var(--search-color);
 }
@@ -890,42 +888,32 @@ so that we can apply CSS-filters to change the arrow color in themes */
 
 .search-results {
 	display: none;
-	padding-bottom: 2em;
 }
 
 .search-results.active {
 	display: block;
-	/* prevent overhanging tabs from moving the first result */
-	clear: both;
 }
 
-.search-results .desc > span {
+.search-results > a {
+	display: flex;
+	/* A little margin ensures the browser's outlining of focused links has room to display. */
+	margin-left: 2px;
+	margin-right: 2px;
+	border-bottom: 1px solid var(--search-result-border-color);
+	gap: 1em;
+}
+
+.search-results > a > div {
+	flex: 1;
+}
+
+.search-results > a > div.desc {
 	white-space: nowrap;
 	text-overflow: ellipsis;
 	overflow: hidden;
 	display: block;
 }
 
-.search-results > a {
-	display: block;
-	/* A little margin ensures the browser's outlining of focused links has room to display. */
-	margin-left: 2px;
-	margin-right: 2px;
-	border-bottom: 1px solid #aaa3;
-}
-
-.search-results > a > div {
-	display: flex;
-	flex-flow: row wrap;
-}
-
-.search-results .result-name, .search-results div.desc {
-	width: 50%;
-}
-.search-results .result-name {
-	padding-right: 1em;
-}
-
 .search-results a:hover,
 .search-results a:focus {
 	background-color: var(--search-result-link-focus-background-color);
@@ -941,13 +929,14 @@ so that we can apply CSS-filters to change the arrow color in themes */
 	border-radius: 3px;
 	border: 1px solid var(--border-color);
 	font-size: 1rem;
+	--popover-arrow-offset: 11px;
 }
 
 /* This rule is to draw the little arrow connecting the settings menu to the gear icon. */
 .popover::before {
 	content: '';
 	position: absolute;
-	right: 11px;
+	right: var(--popover-arrow-offset);
 	border: solid var(--border-color);
 	border-width: 1px 1px 0 0;
 	display: inline-block;
@@ -964,10 +953,7 @@ so that we can apply CSS-filters to change the arrow color in themes */
 /* use larger max-width for help popover, but not for help.html */
 #help.popover {
 	max-width: 600px;
-}
-
-#help.popover::before {
-	right: 48px;
+	--popover-arrow-offset: 48px;
 }
 
 #help dt {
@@ -1107,7 +1093,7 @@ pre.rust .bool-val {
 pre.rust .self {
 	color: var(--code-highlight-self-color);
 }
-pre.rust .attribute {
+pre.rust .attr {
 	color: var(--code-highlight-attribute-color);
 }
 pre.rust .macro,
@@ -1229,13 +1215,16 @@ a.test-arrow {
 	top: 5px;
 	right: 5px;
 	z-index: 1;
+	color: var(--test-arrow-color);
+	background-color: var(--test-arrow-background-color);
+}
+a.test-arrow:hover {
+	color: var(--test-arrow-hover-color);
+	background-color: var(--test-arrow-hover-background-color);
 }
 .example-wrap:hover .test-arrow {
 	visibility: visible;
 }
-a.test-arrow:hover {
-	text-decoration: none;
-}
 
 .code-attribute {
 	font-weight: 300;
@@ -1273,59 +1262,40 @@ h3.variant {
 	margin-left: 24px;
 }
 
-:target > code, :target > .code-header {
-	opacity: 1;
-}
-
 :target {
 	padding-right: 3px;
+	background-color: var(--target-background-color);
+	border-right: 3px solid var(--target-border-color);
 }
 
-.notable-traits-tooltip {
-	display: inline-block;
-	cursor: pointer;
+.notable-traits {
+	color: inherit;
+	margin-right: 15px;
+	position: relative;
 }
 
-.notable-traits:hover .notable-traits-tooltiptext,
-.notable-traits .notable-traits-tooltiptext.force-tooltip {
-	display: inline-block;
-}
-
-.notable-traits .notable-traits-tooltiptext {
-	display: none;
-	padding: 5px 3px 3px 3px;
-	border-radius: 6px;
-	margin-left: 5px;
-	z-index: 10;
-	font-size: 1rem;
-	cursor: default;
+/* placeholder thunk so that the mouse can easily travel from "(i)" to popover
+	the resulting "hover tunnel" is a stepped triangle, approximating
+	https://bjk5.com/post/44698559168/breaking-down-amazons-mega-dropdown */
+.notable-traits:hover::after {
 	position: absolute;
-	border: 1px solid;
+	top: calc(100% - 10px);
+	left: -15px;
+	right: -15px;
+	height: 20px;
+	content: "\00a0";
 }
 
-.notable-traits-tooltip::after {
-	/* The margin on the tooltip does not capture hover events,
-	   this extends the area of hover enough so that mouse hover is not
-	   lost when moving the mouse to the tooltip */
-	content: "\00a0\00a0\00a0";
+.notable .docblock {
+	margin: 0.25em 0.5em;
 }
 
-.notable-traits .notable, .notable-traits .docblock {
-	margin: 0;
-}
-
-.notable-traits .notable {
-	margin: 0;
-	margin-bottom: 13px;
-	font-size: 1.1875rem;
-	font-weight: 600;
-	display: block;
-}
-
-.notable-traits .docblock code.content {
+.notable .docblock pre, .notable .docblock code {
+	background: transparent;
 	margin: 0;
 	padding: 0;
 	font-size: 1.25rem;
+	white-space: pre-wrap;
 }
 
 .search-failed {
@@ -1368,12 +1338,6 @@ h3.variant {
 	font-size: 1rem;
 }
 
-.notable-traits {
-	cursor: pointer;
-	z-index: 2;
-	margin-left: 5px;
-}
-
 #sidebar-toggle {
 	position: sticky;
 	top: 0;
@@ -1546,6 +1510,8 @@ details.rustdoc-toggle > summary.hideme {
 
 details.rustdoc-toggle > summary {
 	list-style: none;
+	/* focus outline is shown on `::before` instead of this */
+	outline: none;
 }
 details.rustdoc-toggle > summary::-webkit-details-marker,
 details.rustdoc-toggle > summary::marker {
@@ -1593,6 +1559,15 @@ details.rustdoc-toggle > summary:hover::before {
 	opacity: 1;
 }
 
+details.rustdoc-toggle > summary:focus-visible::before {
+	/* The SVG is black, and gets turned white using a filter in the dark themes.
+	   Do the same with the outline.
+	   The dotted 1px style is copied from Firefox's focus ring style.
+	*/
+	outline: 1px dotted #000;
+	outline-offset: 1px;
+}
+
 details.rustdoc-toggle.top-doc > summary,
 details.rustdoc-toggle.top-doc > summary::before,
 details.rustdoc-toggle.non-exhaustive > summary,
@@ -1634,11 +1609,11 @@ details.rustdoc-toggle[open] > summary.hideme > span {
 
 details.rustdoc-toggle[open] > summary::before,
 details.rustdoc-toggle[open] > summary.hideme::before {
-	background-image: /* AUTOREPLACE: */url("toggle-minus.svg");
+	background-image: url("toggle-minus-31bbd6e4c77f5c96.svg");
 }
 
 details.rustdoc-toggle > summary::before {
-	background-image: /* AUTOREPLACE: */url("toggle-plus.svg");
+	background-image: url("toggle-plus-1092eb4930d581b0.svg");
 }
 
 details.rustdoc-toggle[open] > summary::before,
@@ -1686,7 +1661,6 @@ in storage.js
 	}
 
 	.rustdoc {
-		padding-top: 0px;
 		/* Sidebar should overlay main content, rather than pushing main content to the right.
 		   Turn off `display: flex` on the body element. */
 		display: block;
@@ -1728,7 +1702,6 @@ in storage.js
 		/* Hide the sidebar offscreen while not in use. Doing this instead of display: none means
 		   the sidebar stays visible for screen readers, which is useful for navigation. */
 		left: -1000px;
-		margin-left: 0;
 		margin: 0;
 		padding: 0;
 		z-index: 11;
@@ -1774,16 +1747,10 @@ in storage.js
 		white-space: nowrap;
 	}
 
-	.mobile-topbar .logo-container {
-		max-height: 45px;
-	}
-
 	.mobile-topbar .logo-container > img {
 		max-width: 35px;
 		max-height: 35px;
-		margin-left: 20px;
-		margin-top: 5px;
-		margin-bottom: 5px;
+		margin: 5px 0 5px 20px;
 	}
 
 	.mobile-topbar {
@@ -1809,7 +1776,6 @@ in storage.js
 
 	.sidebar-elems {
 		margin-top: 1em;
-		background-color: var(--sidebar-background-color);
 	}
 
 	.content {
@@ -1824,21 +1790,6 @@ in storage.js
 		display: block;
 	}
 
-	/* Because of ios, we need to actually have a full height sidebar title so the
-	 * actual sidebar can show up. But then we need to make it transparent so we don't
-	 * hide content. The filler just allows to create the background for the sidebar
-	 * title. But because of the absolute position, I had to lower the z-index.
-	 */
-	#sidebar-filler {
-		position: fixed;
-		left: 45px;
-		width: calc(100% - 45px);
-		top: 0;
-		height: 45px;
-		z-index: -1;
-		border-bottom: 1px solid;
-	}
-
 	#main-content > details.rustdoc-toggle > summary::before,
 	#main-content > div > details.rustdoc-toggle > summary::before {
 		left: -11px;
@@ -1871,37 +1822,22 @@ in storage.js
 		border-bottom: 1px solid;
 	}
 
-	.notable-traits .notable-traits-tooltiptext {
-		left: 0;
-		top: 100%;
-	}
-
 	/* We don't display the help button on mobile devices. */
 	#help-button {
 		display: none;
 	}
 
 	/* Display an alternating layout on tablets and phones */
-	.item-table {
+	.item-table, .item-row, .item-left, .item-right,
+	.search-results > a, .search-results > a > div {
 		display: block;
 	}
-	.item-row {
-		display: flex;
-		flex-flow: column wrap;
-	}
-	.item-left, .item-right {
-		width: 100%;
-	}
 
 	/* Display an alternating layout on tablets and phones */
 	.search-results > a {
-		border-bottom: 1px solid #aaa9;
 		padding: 5px 0px;
 	}
-	.search-results .result-name, .search-results div.desc {
-		width: 100%;
-	}
-	.search-results div.desc, .item-right {
+	.search-results > a > div.desc, .item-right {
 		padding-left: 2em;
 	}
 
@@ -1961,7 +1897,7 @@ in storage.js
 		flex-direction: column;
 	}
 
-	nav.sub form {
+	.search-form {
 		align-self: stretch;
 	}
 
@@ -1978,24 +1914,26 @@ in storage.js
 	}
 }
 
-.method-toggle > summary,
 .implementors-toggle > summary,
 .impl,
 #implementors-list > .docblock,
 .impl-items > section,
-.methods > section
+.impl-items > .rustdoc-toggle > summary,
+.methods > section,
+.methods > .rustdoc-toggle > summary
 {
 	margin-bottom: 0.75em;
 }
 
-.method-toggle[open]:not(:last-child),
+.impl-items > .rustdoc-toggle[open]:not(:last-child),
+.methods > .rustdoc-toggle[open]:not(:last-child),
 .implementors-toggle[open]:not(:last-child) {
 	margin-bottom: 2em;
 }
 
-#trait-implementations-list .method-toggle:not(:last-child),
-#synthetic-implementations-list .method-toggle:not(:last-child),
-#blanket-implementations-list .method-toggle:not(:last-child) {
+#trait-implementations-list .impl-items > .rustdoc-toggle:not(:last-child),
+#synthetic-implementations-list .impl-items > .rustdoc-toggle:not(:last-child),
+#blanket-implementations-list .impl-items > .rustdoc-toggle:not(:last-child) {
 	margin-bottom: 1em;
 }
 
@@ -2008,7 +1946,6 @@ in storage.js
 	font-size: 12px;
 	position: relative;
 	bottom: 1px;
-	background: transparent;
 	border-width: 1px;
 	border-style: solid;
 	border-radius: 50px;
@@ -2032,49 +1969,36 @@ in storage.js
 	padding-bottom: 0;
 }
 
-.scraped-example:not(.expanded) .code-wrapper pre.src-line-numbers {
-	overflow-x: hidden;
-}
-
-.scraped-example .code-wrapper .prev {
-	position: absolute;
-	top: 0.25em;
-	right: 2.25em;
-	z-index: 100;
-	cursor: pointer;
-}
-
-.scraped-example .code-wrapper .next {
-	position: absolute;
-	top: 0.25em;
-	right: 1.25em;
-	z-index: 100;
-	cursor: pointer;
-}
-
+.scraped-example .code-wrapper .next,
+.scraped-example .code-wrapper .prev,
 .scraped-example .code-wrapper .expand {
 	position: absolute;
 	top: 0.25em;
-	right: 0.25em;
-	z-index: 100;
+	z-index: 1;
 	cursor: pointer;
 }
-
-.scraped-example:not(.expanded) .code-wrapper:before {
-	content: " ";
-	width: 100%;
-	height: 5px;
-	position: absolute;
-	z-index: 100;
-	top: 0;
+.scraped-example .code-wrapper .prev {
+	right: 2.25em;
+}
+.scraped-example .code-wrapper .next {
+	right: 1.25em;
+}
+.scraped-example .code-wrapper .expand {
+	right: 0.25em;
 }
 
+.scraped-example:not(.expanded) .code-wrapper:before,
 .scraped-example:not(.expanded) .code-wrapper:after {
 	content: " ";
 	width: 100%;
 	height: 5px;
 	position: absolute;
-	z-index: 100;
+	z-index: 1;
+}
+.scraped-example:not(.expanded) .code-wrapper:before {
+	top: 0;
+}
+.scraped-example:not(.expanded) .code-wrapper:after {
 	bottom: 0;
 }
 
@@ -2083,6 +2007,7 @@ in storage.js
 	padding: 14px 0;
 }
 
+.scraped-example .code-wrapper .src-line-numbers a,
 .scraped-example .code-wrapper .src-line-numbers span {
 	padding: 0 14px;
 }
diff --git a/src/librustdoc/html/static/css/settings.css b/src/librustdoc/html/static/css/settings.css
index 83939f63b4e8..1f6fb961e918 100644
--- a/src/librustdoc/html/static/css/settings.css
+++ b/src/librustdoc/html/static/css/settings.css
@@ -8,7 +8,8 @@
 	flex-wrap: wrap;
 }
 
-.setting-line .radio-line input {
+.setting-line .radio-line input,
+.setting-line .toggle input {
 	margin-right: 0.3em;
 	height: 1.2rem;
 	width: 1.2rem;
@@ -17,9 +18,18 @@
 	outline: none;
 	-webkit-appearance: none;
 	cursor: pointer;
+}
+.setting-line .radio-line input {
 	border-radius: 50%;
 }
-.setting-line .radio-line input + span {
+.setting-line .toggle input:checked {
+	content: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 40 40">\
+		<path d="M7,25L17,32L33,12" fill="none" stroke="black" stroke-width="5"/>\
+		<path d="M7,23L17,30L33,10" fill="none" stroke="white" stroke-width="5"/></svg>');
+}
+
+.setting-line .radio-line input + span,
+.setting-line .toggle span {
 	padding-bottom: 1px;
 }
 
@@ -49,37 +59,6 @@
 	cursor: pointer;
 }
 
-.toggle input {
-	opacity: 0;
-	position: absolute;
-}
-
-.slider {
-	position: relative;
-	width: 45px;
-	min-width: 45px;
-	display: block;
-	height: 28px;
-	margin-right: 20px;
-	cursor: pointer;
-	background-color: #ccc;
-	transition: .3s;
-}
-
-.slider:before {
-	position: absolute;
-	content: "";
-	height: 19px;
-	width: 19px;
-	left: 4px;
-	bottom: 4px;
-	transition: .3s;
-}
-
-input:checked + .slider:before {
-	transform: translateX(19px);
-}
-
 .setting-line > .sub-settings {
 	padding-left: 42px;
 	width: 100%;
@@ -94,7 +73,11 @@ input:checked + .slider:before {
 	box-shadow: inset 0 0 0 3px var(--main-background-color);
 	background-color: var(--settings-input-color);
 }
-.setting-line .radio-line input:focus {
+.setting-line .toggle input:checked {
+	background-color: var(--settings-input-color);
+}
+.setting-line .radio-line input:focus,
+.setting-line .toggle input:focus {
 	box-shadow: 0 0 1px 1px var(--settings-input-color);
 }
 /* In here we combine both `:focus` and `:checked` properties. */
@@ -102,9 +85,7 @@ input:checked + .slider:before {
 	box-shadow: inset 0 0 0 3px var(--main-background-color),
 		0 0 2px 2px var(--settings-input-color);
 }
-.setting-line .radio-line input:hover {
+.setting-line .radio-line input:hover,
+.setting-line .toggle input:hover {
 	border-color: var(--settings-input-color) !important;
 }
-input:checked + .slider {
-	background-color: var(--settings-input-color);
-}
diff --git a/src/librustdoc/html/static/css/themes/ayu.css b/src/librustdoc/html/static/css/themes/ayu.css
index 33817c16808c..db311bccd6dc 100644
--- a/src/librustdoc/html/static/css/themes/ayu.css
+++ b/src/librustdoc/html/static/css/themes/ayu.css
@@ -38,6 +38,7 @@ Original by Dempfi (https://github.com/dempfi/ayu)
 	--sidebar-link-color: #53b1db;
 	--sidebar-current-link-background-color: transparent;
 	--search-result-link-focus-background-color: #3c3c3c;
+	--search-result-border-color: #aaa3;
 	--stab-background-color: #314559;
 	--stab-code-color: #e6e1cf;
 	--search-color: #fff;
@@ -55,16 +56,25 @@ Original by Dempfi (https://github.com/dempfi/ayu)
 	--code-highlight-question-mark-color: #ff9011;
 	--code-highlight-comment-color: #788797;
 	--code-highlight-doc-comment-color: #a1ac88;
-}
-
-.slider {
-	background-color: #ccc;
-}
-.slider:before {
-	background-color: white;
-}
-input:focus + .slider {
-	box-shadow: 0 0 0 2px #0a84ff, 0 0 0 6px rgba(10, 132, 255, 0.3);
+	--example-line-numbers-border-color: none;
+	--src-line-numbers-span-color: #5c6773;
+	--src-line-number-highlighted-background-color: rgba(255, 236, 164, 0.06);
+	--test-arrow-color: #788797;
+	--test-arrow-background-color: rgba(57, 175, 215, 0.09);
+	--test-arrow-hover-color: #c5c5c5;
+	--test-arrow-hover-background-color: rgba(57, 175, 215, 0.368);
+	--target-background-color: rgba(255, 236, 164, 0.06);
+	--target-border-color: rgba(255, 180, 76, 0.85);
+	--rust-logo-filter: drop-shadow(1px 0 0px #fff)
+		drop-shadow(0 1px 0 #fff)
+		drop-shadow(-1px 0 0 #fff)
+		drop-shadow(0 -1px 0 #fff);
+	/* match border-color; uses https://codepen.io/sosuke/pen/Pjoqqp */
+	--crate-search-div-filter: invert(41%) sepia(12%) saturate(487%) hue-rotate(171deg)
+		brightness(94%) contrast(94%);
+	--crate-search-div-hover-filter: invert(98%) sepia(12%) saturate(81%) hue-rotate(343deg)
+		brightness(113%) contrast(76%);
+	--crate-search-hover-border: #e0e0e0;
 }
 
 h1, h2, h3, h4 {
@@ -96,13 +106,6 @@ pre, .rustdoc.source .example-wrap {
 	color: #e6e1cf;
 }
 
-.rust-logo {
-	filter: drop-shadow(1px 0 0px #fff)
-		drop-shadow(0 1px 0 #fff)
-		drop-shadow(-1px 0 0 #fff)
-		drop-shadow(0 -1px 0 #fff);
-}
-
 .sidebar .current,
 .sidebar a:hover {
 	color: #ffb44c;
@@ -112,10 +115,8 @@ pre, .rustdoc.source .example-wrap {
 	color: #ff7733;
 }
 
-.src-line-numbers span { color: #5c6773; }
 .src-line-numbers .line-highlighted {
 	color: #708090;
-	background-color: rgba(255, 236, 164, 0.06);
 	padding-right: 4px;
 	border-right: 1px solid #ffb44c;
 }
@@ -150,17 +151,6 @@ details.rustdoc-toggle > summary::before {
 	filter: invert(100%);
 }
 
-#crate-search-div::after {
-	/* match border-color; uses https://codepen.io/sosuke/pen/Pjoqqp */
-	filter: invert(41%) sepia(12%) saturate(487%) hue-rotate(171deg) brightness(94%) contrast(94%);
-}
-#crate-search:hover, #crate-search:focus {
-	border-color: #e0e0e0 !important;
-}
-#crate-search-div:hover::after, #crate-search-div:focus-within::after {
-	filter: invert(98%) sepia(12%) saturate(81%) hue-rotate(343deg) brightness(113%) contrast(76%);
-}
-
 .module-item .stab,
 .import-item .stab {
 	color: #000;
@@ -170,34 +160,6 @@ details.rustdoc-toggle > summary::before {
 	color: #788797;
 }
 
-.src-line-numbers :target { background-color: transparent; }
-
-pre.example-line-numbers {
-	color: #5c67736e;
-	border: none;
-}
-
-a.test-arrow {
-	font-size: 100%;
-	color: #788797;
-	border-radius: 4px;
-	background-color: rgba(57, 175, 215, 0.09);
-}
-
-a.test-arrow:hover {
-	background-color: rgba(57, 175, 215, 0.368);
-	color: #c5c5c5;
-}
-
-:target {
-	background: rgba(255, 236, 164, 0.06);
-	border-right: 3px solid rgba(255, 180, 76, 0.85);
-}
-
-.search-failed a {
-	color: #39AFD7;
-}
-
 .tooltip::after {
 	background-color: #314559;
 	color: #c5c5c5;
@@ -207,10 +169,6 @@ a.test-arrow:hover {
 	border-color: transparent #314559 transparent transparent;
 }
 
-.notable-traits-tooltiptext {
-	background-color: #314559;
-}
-
 #titles > button.selected {
 	background-color: #141920 !important;
 	border-bottom: 1px solid #ffb44c !important;
diff --git a/src/librustdoc/html/static/css/themes/dark.css b/src/librustdoc/html/static/css/themes/dark.css
index d88710288b90..b2f2c77f5475 100644
--- a/src/librustdoc/html/static/css/themes/dark.css
+++ b/src/librustdoc/html/static/css/themes/dark.css
@@ -33,6 +33,7 @@
 	--sidebar-link-color: #fdbf35;
 	--sidebar-current-link-background-color: #444;
 	--search-result-link-focus-background-color: #616161;
+	--search-result-border-color: #aaa3;
 	--stab-background-color: #314559;
 	--stab-code-color: #e6e1cf;
 	--search-color: #111;
@@ -50,28 +51,25 @@
 	--code-highlight-question-mark-color: #ff9011;
 	--code-highlight-comment-color: #8d8d8b;
 	--code-highlight-doc-comment-color: #8ca375;
-}
-
-.slider {
-	background-color: #ccc;
-}
-.slider:before {
-	background-color: white;
-}
-input:focus + .slider {
-	box-shadow: 0 0 0 2px #0a84ff, 0 0 0 6px rgba(10, 132, 255, 0.3);
-}
-
-.rust-logo {
-	filter: drop-shadow(1px 0 0px #fff)
+	--example-line-numbers-border-color: #4a4949;
+	--src-line-numbers-span-color: #3b91e2;
+	--src-line-number-highlighted-background-color: #0a042f;
+	--test-arrow-color: #dedede;
+	--test-arrow-background-color: rgba(78, 139, 202, 0.2);
+	--test-arrow-hover-color: #dedede;
+	--test-arrow-hover-background-color: #4e8bca;
+	--target-background-color: #494a3d;
+	--target-border-color: #bb7410;
+	--rust-logo-filter: drop-shadow(1px 0 0px #fff)
 		drop-shadow(0 1px 0 #fff)
 		drop-shadow(-1px 0 0 #fff)
-		drop-shadow(0 -1px 0 #fff)
-}
-
-.src-line-numbers span { color: #3B91E2; }
-.src-line-numbers .line-highlighted {
-	background-color: #0a042f !important;
+		drop-shadow(0 -1px 0 #fff);
+	/* match border-color; uses https://codepen.io/sosuke/pen/Pjoqqp */
+	--crate-search-div-filter: invert(94%) sepia(0%) saturate(721%) hue-rotate(255deg)
+		brightness(90%) contrast(90%);
+	--crate-search-div-hover-filter: invert(69%) sepia(60%) saturate(6613%) hue-rotate(184deg)
+		brightness(100%) contrast(91%);
+	--crate-search-hover-border: #2196f3;
 }
 
 .content .item-info::before { color: #ccc; }
@@ -84,41 +82,6 @@ details.rustdoc-toggle > summary::before {
 	filter: invert(100%);
 }
 
-#crate-search-div::after {
-	/* match border-color; uses https://codepen.io/sosuke/pen/Pjoqqp */
-	filter: invert(94%) sepia(0%) saturate(721%) hue-rotate(255deg) brightness(90%) contrast(90%);
-}
-#crate-search:hover, #crate-search:focus {
-	border-color: #2196f3 !important;
-}
-#crate-search-div:hover::after, #crate-search-div:focus-within::after {
-	filter: invert(69%) sepia(60%) saturate(6613%) hue-rotate(184deg) brightness(100%) contrast(91%);
-}
-
-.src-line-numbers :target { background-color: transparent; }
-
-pre.example-line-numbers {
-	border-color: #4a4949;
-}
-
-a.test-arrow {
-	color: #dedede;
-	background-color: rgba(78, 139, 202, 0.2);
-}
-
-a.test-arrow:hover{
-	background-color: #4e8bca;
-}
-
-:target {
-	background-color: #494a3d;
-	border-right: 3px solid #bb7410;
-}
-
-.search-failed a {
-	color: #0089ff;
-}
-
 .tooltip::after {
 	background-color: #000;
 	color: #fff;
@@ -129,10 +92,6 @@ a.test-arrow:hover{
 	border-color: transparent black transparent transparent;
 }
 
-.notable-traits-tooltiptext {
-	background-color: #111;
-}
-
 #titles > button:not(.selected) {
 	background-color: #252525;
 	border-top-color: #252525;
diff --git a/src/librustdoc/html/static/css/themes/light.css b/src/librustdoc/html/static/css/themes/light.css
index cadc71dab959..e81327956888 100644
--- a/src/librustdoc/html/static/css/themes/light.css
+++ b/src/librustdoc/html/static/css/themes/light.css
@@ -33,6 +33,7 @@
 	--sidebar-link-color: #356da4;
 	--sidebar-current-link-background-color: #fff;
 	--search-result-link-focus-background-color: #ccc;
+	--search-result-border-color: #aaa3;
 	--stab-background-color: #fff5d6;
 	--stab-code-color: #000;
 	--search-color: #000;
@@ -50,27 +51,22 @@
 	--code-highlight-question-mark-color: #ff9011;
 	--code-highlight-comment-color: #8e908c;
 	--code-highlight-doc-comment-color: #4d4d4c;
-}
-
-.slider {
-	background-color: #ccc;
-}
-.slider:before {
-	background-color: white;
-}
-input:focus + .slider {
-	box-shadow: 0 0 0 2px #0a84ff, 0 0 0 6px rgba(10, 132, 255, 0.3);
-}
-
-.rust-logo {
-	/* This rule exists to force other themes to explicitly style the logo.
-	 * Rustdoc has a custom linter for this purpose.
-	 */
-}
-
-.src-line-numbers span { color: #c67e2d; }
-.src-line-numbers .line-highlighted {
-	background-color: #FDFFD3 !important;
+	--example-line-numbers-border-color: #c7c7c7;
+	--src-line-numbers-span-color: #c67e2d;
+	--src-line-number-highlighted-background-color: #fdffd3;
+	--test-arrow-color: #f5f5f5;
+	--test-arrow-background-color: rgba(78, 139, 202, 0.2);
+	--test-arrow-hover-color: #f5f5f5;
+	--test-arrow-hover-background-color: #4e8bca;
+	--target-background-color: #fdFfd3;
+	--target-border-color: #ad7c37;
+	--rust-logo-filter: initial;
+	/* match border-color; uses https://codepen.io/sosuke/pen/Pjoqqp */
+	--crate-search-div-filter: invert(100%) sepia(0%) saturate(4223%) hue-rotate(289deg)
+		brightness(114%) contrast(76%);
+	--crate-search-div-hover-filter: invert(44%) sepia(18%) saturate(23%) hue-rotate(317deg)
+		brightness(96%) contrast(93%);
+	--crate-search-hover-border: #717171;
 }
 
 .content .item-info::before { color: #ccc; }
@@ -79,41 +75,6 @@ body.source .example-wrap pre.rust a {
 	background: #eee;
 }
 
-#crate-search-div::after {
-	/* match border-color; uses https://codepen.io/sosuke/pen/Pjoqqp */
-	filter: invert(100%) sepia(0%) saturate(4223%) hue-rotate(289deg) brightness(114%) contrast(76%);
-}
-#crate-search:hover, #crate-search:focus {
-	border-color: #717171 !important;
-}
-#crate-search-div:hover::after, #crate-search-div:focus-within::after {
-	filter: invert(44%) sepia(18%) saturate(23%) hue-rotate(317deg) brightness(96%) contrast(93%);
-}
-
-.src-line-numbers :target { background-color: transparent; }
-
-pre.example-line-numbers {
-	border-color: #c7c7c7;
-}
-
-a.test-arrow {
-	color: #f5f5f5;
-	background-color: rgba(78, 139, 202, 0.2);
-}
-
-a.test-arrow:hover{
-	background-color: #4e8bca;
-}
-
-:target {
-	background: #FDFFD3;
-	border-right: 3px solid #AD7C37;
-}
-
-.search-failed a {
-	color: #3873AD;
-}
-
 .tooltip::after {
 	background-color: #000;
 	color: #fff;
@@ -123,10 +84,6 @@ a.test-arrow:hover{
 	border-color: transparent black transparent transparent;
 }
 
-.notable-traits-tooltiptext {
-	background-color: #eee;
-}
-
 #titles > button:not(.selected) {
 	background-color: #e6e6e6;
 	border-top-color: #e6e6e6;
diff --git a/src/librustdoc/html/static/fonts/README.txt b/src/librustdoc/html/static/fonts/README.txt
new file mode 100644
index 000000000000..0db15996d2ec
--- /dev/null
+++ b/src/librustdoc/html/static/fonts/README.txt
@@ -0,0 +1,12 @@
+The Nanum Barun Gothic fonts are shipped with rustdoc because the default fonts
+on many Windows installs render Korean very badly. See:
+ - https://github.com/rust-lang/rust/pull/84048,
+ - https://github.com/rust-lang/rust/issues/84035
+ - https://github.com/rust-lang/rust/pull/90232
+
+The font files were generated with these commands:
+
+```sh
+pyftsubset NanumBarunGothic.ttf \
+--unicodes=U+AC00-D7AF:U+1100-11FF,U+3130-318F,U+A960-A97F,U+D7B0-D7FF \
+--output-file=NanumBarunGothic.ttf.woff2 --flavor=woff2
diff --git a/src/librustdoc/html/static/js/main.js b/src/librustdoc/html/static/js/main.js
index 0b816eace64b..0538762e44d0 100644
--- a/src/librustdoc/html/static/js/main.js
+++ b/src/librustdoc/html/static/js/main.js
@@ -183,9 +183,9 @@ function browserSupportsHistoryApi() {
 }
 
 // eslint-disable-next-line no-unused-vars
-function loadCss(cssFileName) {
+function loadCss(cssUrl) {
     const link = document.createElement("link");
-    link.href = resourcePath(cssFileName, ".css");
+    link.href = cssUrl;
     link.type = "text/css";
     link.rel = "stylesheet";
     document.getElementsByTagName("head")[0].appendChild(link);
@@ -208,8 +208,8 @@ function loadCss(cssFileName) {
         event.preventDefault();
         // Sending request for the CSS and the JS files at the same time so it will
         // hopefully be loaded when the JS will generate the settings content.
-        loadCss("settings");
-        loadScript(resourcePath("settings", ".js"));
+        loadCss(getVar("static-root-path") + getVar("settings-css"));
+        loadScript(getVar("static-root-path") + getVar("settings-js"));
     };
 
     window.searchState = {
@@ -286,7 +286,7 @@ function loadCss(cssFileName) {
             function loadSearch() {
                 if (!searchLoaded) {
                     searchLoaded = true;
-                    loadScript(resourcePath("search", ".js"));
+                    loadScript(getVar("static-root-path") + getVar("search-js"));
                     loadScript(resourcePath("search-index", ".js"));
                 }
             }
@@ -790,6 +790,19 @@ function loadCss(cssFileName) {
             // we need to switch away from mobile mode and make the main content area scrollable.
             hideSidebar();
         }
+        if (window.CURRENT_NOTABLE_ELEMENT) {
+            // As a workaround to the behavior of `contains: layout` used in doc togglers, the
+            // notable traits popup is positioned using javascript.
+            //
+            // This means when the window is resized, we need to redo the layout.
+            const base = window.CURRENT_NOTABLE_ELEMENT.NOTABLE_BASE;
+            const force_visible = base.NOTABLE_FORCE_VISIBLE;
+            hideNotable();
+            if (force_visible) {
+                showNotable(base);
+                base.NOTABLE_FORCE_VISIBLE = true;
+            }
+        }
     });
 
     function handleClick(id, f) {
@@ -822,10 +835,121 @@ function loadCss(cssFileName) {
         });
     });
 
+    function showNotable(e) {
+        if (!window.NOTABLE_TRAITS) {
+            const data = document.getElementById("notable-traits-data");
+            if (data) {
+                window.NOTABLE_TRAITS = JSON.parse(data.innerText);
+            } else {
+                throw new Error("showNotable() called on page without any notable traits!");
+            }
+        }
+        if (window.CURRENT_NOTABLE_ELEMENT && window.CURRENT_NOTABLE_ELEMENT.NOTABLE_BASE === e) {
+            // Make this function idempotent.
+            return;
+        }
+        hideNotable();
+        const ty = e.getAttribute("data-ty");
+        const wrapper = document.createElement("div");
+        wrapper.innerHTML = "<div class=\"docblock\">" + window.NOTABLE_TRAITS[ty] + "</div>";
+        wrapper.className = "notable popover";
+        const focusCatcher = document.createElement("div");
+        focusCatcher.setAttribute("tabindex", "0");
+        focusCatcher.onfocus = hideNotable;
+        wrapper.appendChild(focusCatcher);
+        const pos = e.getBoundingClientRect();
+        // 5px overlap so that the mouse can easily travel from place to place
+        wrapper.style.top = (pos.top + window.scrollY + pos.height) + "px";
+        wrapper.style.left = 0;
+        wrapper.style.right = "auto";
+        wrapper.style.visibility = "hidden";
+        const body = document.getElementsByTagName("body")[0];
+        body.appendChild(wrapper);
+        const wrapperPos = wrapper.getBoundingClientRect();
+        // offset so that the arrow points at the center of the "(i)"
+        const finalPos = pos.left + window.scrollX - wrapperPos.width + 24;
+        if (finalPos > 0) {
+            wrapper.style.left = finalPos + "px";
+        } else {
+            wrapper.style.setProperty(
+                "--popover-arrow-offset",
+                (wrapperPos.right - pos.right + 4) + "px"
+            );
+        }
+        wrapper.style.visibility = "";
+        window.CURRENT_NOTABLE_ELEMENT = wrapper;
+        window.CURRENT_NOTABLE_ELEMENT.NOTABLE_BASE = e;
+        wrapper.onpointerleave = function(ev) {
+            // If this is a synthetic touch event, ignore it. A click event will be along shortly.
+            if (ev.pointerType !== "mouse") {
+                return;
+            }
+            if (!e.NOTABLE_FORCE_VISIBLE && !elemIsInParent(event.relatedTarget, e)) {
+                hideNotable();
+            }
+        };
+    }
+
+    function notableBlurHandler(event) {
+        if (window.CURRENT_NOTABLE_ELEMENT &&
+            !elemIsInParent(document.activeElement, window.CURRENT_NOTABLE_ELEMENT) &&
+            !elemIsInParent(event.relatedTarget, window.CURRENT_NOTABLE_ELEMENT) &&
+            !elemIsInParent(document.activeElement, window.CURRENT_NOTABLE_ELEMENT.NOTABLE_BASE) &&
+            !elemIsInParent(event.relatedTarget, window.CURRENT_NOTABLE_ELEMENT.NOTABLE_BASE)
+        ) {
+            // Work around a difference in the focus behaviour between Firefox, Chrome, and Safari.
+            // When I click the button on an already-opened notable trait popover, Safari
+            // hides the popover and then immediately shows it again, while everyone else hides it
+            // and it stays hidden.
+            //
+            // To work around this, make sure the click finishes being dispatched before
+            // hiding the popover. Since `hideNotable()` is idempotent, this makes Safari behave
+            // consistently with the other two.
+            setTimeout(hideNotable, 0);
+        }
+    }
+
+    function hideNotable() {
+        if (window.CURRENT_NOTABLE_ELEMENT) {
+            if (window.CURRENT_NOTABLE_ELEMENT.NOTABLE_BASE.NOTABLE_FORCE_VISIBLE) {
+                window.CURRENT_NOTABLE_ELEMENT.NOTABLE_BASE.focus();
+                window.CURRENT_NOTABLE_ELEMENT.NOTABLE_BASE.NOTABLE_FORCE_VISIBLE = false;
+            }
+            const body = document.getElementsByTagName("body")[0];
+            body.removeChild(window.CURRENT_NOTABLE_ELEMENT);
+            window.CURRENT_NOTABLE_ELEMENT = null;
+        }
+    }
+
     onEachLazy(document.getElementsByClassName("notable-traits"), e => {
         e.onclick = function() {
-            this.getElementsByClassName("notable-traits-tooltiptext")[0]
-                .classList.toggle("force-tooltip");
+            this.NOTABLE_FORCE_VISIBLE = this.NOTABLE_FORCE_VISIBLE ? false : true;
+            if (window.CURRENT_NOTABLE_ELEMENT && !this.NOTABLE_FORCE_VISIBLE) {
+                hideNotable();
+            } else {
+                showNotable(this);
+                window.CURRENT_NOTABLE_ELEMENT.setAttribute("tabindex", "0");
+                window.CURRENT_NOTABLE_ELEMENT.focus();
+                window.CURRENT_NOTABLE_ELEMENT.onblur = notableBlurHandler;
+            }
+            return false;
+        };
+        e.onpointerenter = function(ev) {
+            // If this is a synthetic touch event, ignore it. A click event will be along shortly.
+            if (ev.pointerType !== "mouse") {
+                return;
+            }
+            showNotable(this);
+        };
+        e.onpointerleave = function(ev) {
+            // If this is a synthetic touch event, ignore it. A click event will be along shortly.
+            if (ev.pointerType !== "mouse") {
+                return;
+            }
+            if (!this.NOTABLE_FORCE_VISIBLE &&
+                !elemIsInParent(event.relatedTarget, window.CURRENT_NOTABLE_ELEMENT)) {
+                hideNotable();
+            }
         };
     });
 
@@ -932,9 +1056,10 @@ function loadCss(cssFileName) {
      * Hide all the popover menus.
      */
     window.hidePopoverMenus = function() {
-        onEachLazy(document.querySelectorAll(".search-container .popover"), elem => {
+        onEachLazy(document.querySelectorAll(".search-form .popover"), elem => {
             elem.style.display = "none";
         });
+        hideNotable();
     };
 
     /**
diff --git a/src/librustdoc/html/static/js/search.js b/src/librustdoc/html/static/js/search.js
index d04ec357c40a..4999bb359948 100644
--- a/src/librustdoc/html/static/js/search.js
+++ b/src/librustdoc/html/static/js/search.js
@@ -1491,6 +1491,7 @@ function initSearch(rawSearchIndex) {
         const target = searchState.focusedByTab[searchState.currentTab] ||
             document.querySelectorAll(".search-results.active a").item(0) ||
             document.querySelectorAll("#titles > button").item(searchState.currentTab);
+        searchState.focusedByTab[searchState.currentTab] = null;
         if (target) {
             target.focus();
         }
@@ -1593,7 +1594,6 @@ function initSearch(rawSearchIndex) {
                 link.className = "result-" + type;
                 link.href = item.href;
 
-                const wrapper = document.createElement("div");
                 const resultName = document.createElement("div");
                 resultName.className = "result-name";
 
@@ -1614,16 +1614,13 @@ function initSearch(rawSearchIndex) {
                 resultName.insertAdjacentHTML(
                     "beforeend",
                     item.displayPath + "<span class=\"" + type + "\">" + name + extra + "</span>");
-                wrapper.appendChild(resultName);
+                link.appendChild(resultName);
 
                 const description = document.createElement("div");
                 description.className = "desc";
-                const spanDesc = document.createElement("span");
-                spanDesc.insertAdjacentHTML("beforeend", item.desc);
+                description.insertAdjacentHTML("beforeend", item.desc);
 
-                description.appendChild(spanDesc);
-                wrapper.appendChild(description);
-                link.appendChild(wrapper);
+                link.appendChild(description);
                 output.appendChild(link);
             });
         } else if (query.error === null) {
diff --git a/src/librustdoc/html/static/js/settings.js b/src/librustdoc/html/static/js/settings.js
index 5e1c7e6f03e7..95cc265f1bdf 100644
--- a/src/librustdoc/html/static/js/settings.js
+++ b/src/librustdoc/html/static/js/settings.js
@@ -66,8 +66,7 @@
 
     function setEvents(settingsElement) {
         updateLightAndDark();
-        onEachLazy(settingsElement.getElementsByClassName("slider"), elem => {
-            const toggle = elem.previousElementSibling;
+        onEachLazy(settingsElement.querySelectorAll("input[type=\"checkbox\"]"), toggle => {
             const settingId = toggle.id;
             const settingValue = getSettingValue(settingId);
             if (settingValue !== null) {
@@ -139,7 +138,6 @@
                 const checked = setting["default"] === true ? " checked" : "";
                 output += `<label class="toggle">\
                         <input type="checkbox" id="${js_data_name}"${checked}>\
-                        <span class="slider"></span>\
                         <span class="label">${setting_name}</span>\
                     </label>`;
             }
@@ -154,7 +152,9 @@
      * @return {HTMLElement}
      */
     function buildSettingsPage() {
-        const themes = getVar("themes").split(",");
+        const theme_names = getVar("themes").split(",").filter(t => t);
+        theme_names.push("light", "dark", "ayu");
+
         const settings = [
             {
                 "name": "Use system theme",
@@ -165,19 +165,19 @@
                 "name": "Theme",
                 "js_name": "theme",
                 "default": "light",
-                "options": themes,
+                "options": theme_names,
             },
             {
                 "name": "Preferred light theme",
                 "js_name": "preferred-light-theme",
                 "default": "light",
-                "options": themes,
+                "options": theme_names,
             },
             {
                 "name": "Preferred dark theme",
                 "js_name": "preferred-dark-theme",
                 "default": "dark",
-                "options": themes,
+                "options": theme_names,
             },
             {
                 "name": "Auto-hide item contents for large items",
diff --git a/src/librustdoc/html/static/js/source-script.js b/src/librustdoc/html/static/js/source-script.js
index 0b9368dd8994..5db768c1c575 100644
--- a/src/librustdoc/html/static/js/source-script.js
+++ b/src/librustdoc/html/static/js/source-script.js
@@ -157,7 +157,7 @@ function highlightSourceLines(match) {
         x.scrollIntoView();
     }
     onEachLazy(document.getElementsByClassName("src-line-numbers"), e => {
-        onEachLazy(e.getElementsByTagName("span"), i_e => {
+        onEachLazy(e.getElementsByTagName("a"), i_e => {
             removeClass(i_e, "line-highlighted");
         });
     });
@@ -188,8 +188,13 @@ const handleSourceHighlight = (function() {
 
     return ev => {
         let cur_line_id = parseInt(ev.target.id, 10);
-        // It can happen when clicking not on a line number span.
-        if (isNaN(cur_line_id)) {
+        // This event handler is attached to the entire line number column, but it should only
+        // be run if one of the anchors is clicked. It also shouldn't do anything if the anchor
+        // is clicked with a modifier key (to open a new browser tab).
+        if (isNaN(cur_line_id) ||
+            ev.ctrlKey ||
+            ev.altKey ||
+            ev.metaKey) {
             return;
         }
         ev.preventDefault();
diff --git a/src/librustdoc/html/static/js/storage.js b/src/librustdoc/html/static/js/storage.js
index b462a2c50f14..db2db83ca631 100644
--- a/src/librustdoc/html/static/js/storage.js
+++ b/src/librustdoc/html/static/js/storage.js
@@ -126,33 +126,29 @@ function getCurrentValue(name) {
     }
 }
 
-function switchTheme(styleElem, mainStyleElem, newTheme, saveTheme) {
-    const newHref = mainStyleElem.href.replace(
-        /\/rustdoc([^/]*)\.css/, "/" + newTheme + "$1" + ".css");
-
+function switchTheme(styleElem, mainStyleElem, newThemeName, saveTheme) {
     // If this new value comes from a system setting or from the previously
     // saved theme, no need to save it.
     if (saveTheme) {
-        updateLocalStorage("theme", newTheme);
+        updateLocalStorage("theme", newThemeName);
     }
 
-    if (styleElem.href === newHref) {
-        return;
-    }
-
-    let found = false;
     if (savedHref.length === 0) {
         onEachLazy(document.getElementsByTagName("link"), el => {
             savedHref.push(el.href);
         });
     }
-    onEach(savedHref, el => {
-        if (el === newHref) {
-            found = true;
+    const newHref = savedHref.find(url => {
+        const m = url.match(/static\.files\/(.*)-[a-f0-9]{16}\.css$/);
+        if (m && m[1] === newThemeName) {
+            return true;
+        }
+        const m2 = url.match(/\/([^/]*)\.css$/);
+        if (m2 && m2[1].startsWith(newThemeName)) {
             return true;
         }
     });
-    if (found) {
+    if (newHref && newHref !== styleElem.href) {
         styleElem.href = newHref;
     }
 }
diff --git a/src/librustdoc/html/static_files.rs b/src/librustdoc/html/static_files.rs
index 75f2b7e3570d..b4d4150cddbb 100644
--- a/src/librustdoc/html/static_files.rs
+++ b/src/librustdoc/html/static_files.rs
@@ -2,167 +2,132 @@
 //!
 //! All the static files are included here for centralized access in case anything other than the
 //! HTML rendering code (say, the theme checker) needs to access one of these files.
-//!
-//! Note about types: CSS and JavaScript files are included as `&'static str` to allow for the
-//! minifier to run on them. All other files are included as `&'static [u8]` so they can be
-//! directly written to a `Write` handle.
 
-/// The file contents of the main `rustdoc.css` file, responsible for the core layout of the page.
-pub(crate) static RUSTDOC_CSS: &str = include_str!("static/css/rustdoc.css");
+use rustc_data_structures::fx::FxHasher;
+use std::hash::Hasher;
+use std::path::{Path, PathBuf};
+use std::{fmt, str};
 
-/// The file contents of `settings.css`, responsible for the items on the settings page.
-pub(crate) static SETTINGS_CSS: &str = include_str!("static/css/settings.css");
-
-/// The file contents of the `noscript.css` file, used in case JS isn't supported or is disabled.
-pub(crate) static NOSCRIPT_CSS: &str = include_str!("static/css/noscript.css");
-
-/// The file contents of `normalize.css`, included to even out standard elements between browser
-/// implementations.
-pub(crate) static NORMALIZE_CSS: &str = include_str!("static/css/normalize.css");
-
-/// The file contents of `main.js`, which contains the core JavaScript used on documentation pages,
-/// including search behavior and docblock folding, among others.
-pub(crate) static MAIN_JS: &str = include_str!("static/js/main.js");
-
-/// The file contents of `search.js`, which contains the search behavior.
-pub(crate) static SEARCH_JS: &str = include_str!("static/js/search.js");
-
-/// The file contents of `settings.js`, which contains the JavaScript used to handle the settings
-/// page.
-pub(crate) static SETTINGS_JS: &str = include_str!("static/js/settings.js");
-
-/// The file contents of `storage.js`, which contains functionality related to browser Local
-/// Storage, used to store documentation settings.
-pub(crate) static STORAGE_JS: &str = include_str!("static/js/storage.js");
-
-/// The file contents of `scraped-examples.js`, which contains functionality related to the
-/// --scrape-examples flag that inserts automatically-found examples of usages of items.
-pub(crate) static SCRAPE_EXAMPLES_JS: &str = include_str!("static/js/scrape-examples.js");
-
-pub(crate) static SCRAPE_EXAMPLES_HELP_MD: &str = include_str!("static/scrape-examples-help.md");
-
-/// The file contents of `wheel.svg`, the icon used for the settings button.
-pub(crate) static WHEEL_SVG: &[u8] = include_bytes!("static/images/wheel.svg");
-
-/// The file contents of `clipboard.svg`, the icon used for the "copy path" button.
-pub(crate) static CLIPBOARD_SVG: &[u8] = include_bytes!("static/images/clipboard.svg");
-
-/// The file contents of `down-arrow.svg`, the icon used for the crate choice combobox.
-pub(crate) static DOWN_ARROW_SVG: &[u8] = include_bytes!("static/images/down-arrow.svg");
-
-/// The file contents of `toggle-minus.svg`, the icon used for opened toggles.
-pub(crate) static TOGGLE_MINUS_PNG: &[u8] = include_bytes!("static/images/toggle-minus.svg");
-
-/// The file contents of `toggle-plus.svg`, the icon used for closed toggles.
-pub(crate) static TOGGLE_PLUS_PNG: &[u8] = include_bytes!("static/images/toggle-plus.svg");
-
-/// The contents of `COPYRIGHT.txt`, the license listing for files distributed with documentation
-/// output.
-pub(crate) static COPYRIGHT: &[u8] = include_bytes!("static/COPYRIGHT.txt");
-
-/// The contents of `LICENSE-APACHE.txt`, the text of the Apache License, version 2.0.
-pub(crate) static LICENSE_APACHE: &[u8] = include_bytes!("static/LICENSE-APACHE.txt");
-
-/// The contents of `LICENSE-MIT.txt`, the text of the MIT License.
-pub(crate) static LICENSE_MIT: &[u8] = include_bytes!("static/LICENSE-MIT.txt");
-
-/// The contents of `rust-logo.svg`, the default icon of the documentation.
-pub(crate) static RUST_LOGO_SVG: &[u8] = include_bytes!("static/images/rust-logo.svg");
-
-/// The default documentation favicons (SVG and PNG fallbacks)
-pub(crate) static RUST_FAVICON_SVG: &[u8] = include_bytes!("static/images/favicon.svg");
-pub(crate) static RUST_FAVICON_PNG_16: &[u8] = include_bytes!("static/images/favicon-16x16.png");
-pub(crate) static RUST_FAVICON_PNG_32: &[u8] = include_bytes!("static/images/favicon-32x32.png");
-
-/// The built-in themes given to every documentation site.
-pub(crate) mod themes {
-    /// The "light" theme, selected by default when no setting is available. Used as the basis for
-    /// the `--check-theme` functionality.
-    pub(crate) static LIGHT: &str = include_str!("static/css/themes/light.css");
-
-    /// The "dark" theme.
-    pub(crate) static DARK: &str = include_str!("static/css/themes/dark.css");
-
-    /// The "ayu" theme.
-    pub(crate) static AYU: &str = include_str!("static/css/themes/ayu.css");
+pub(crate) struct StaticFile {
+    pub(crate) filename: PathBuf,
+    pub(crate) bytes: &'static [u8],
 }
 
-/// Files related to the Fira Sans font.
-pub(crate) mod fira_sans {
-    /// The file `FiraSans-Regular.woff2`, the Regular variant of the Fira Sans font in woff2.
-    pub(crate) static REGULAR: &[u8] = include_bytes!("static/fonts/FiraSans-Regular.woff2");
+impl StaticFile {
+    fn new(filename: &str, bytes: &'static [u8]) -> StaticFile {
+        Self { filename: static_filename(filename, bytes), bytes }
+    }
 
-    /// The file `FiraSans-Medium.woff2`, the Medium variant of the Fira Sans font in woff2.
-    pub(crate) static MEDIUM: &[u8] = include_bytes!("static/fonts/FiraSans-Medium.woff2");
+    pub(crate) fn minified(&self) -> Vec<u8> {
+        let extension = match self.filename.extension() {
+            Some(e) => e,
+            None => return self.bytes.to_owned(),
+        };
+        if extension == "css" {
+            minifier::css::minify(str::from_utf8(self.bytes).unwrap()).unwrap().to_string().into()
+        } else if extension == "js" {
+            minifier::js::minify(str::from_utf8(self.bytes).unwrap()).to_string().into()
+        } else {
+            self.bytes.to_owned()
+        }
+    }
 
-    /// The file `FiraSans-LICENSE.txt`, the license text for the Fira Sans font.
-    pub(crate) static LICENSE: &[u8] = include_bytes!("static/fonts/FiraSans-LICENSE.txt");
+    pub(crate) fn output_filename(&self) -> &Path {
+        &self.filename
+    }
 }
 
-/// Files related to the Source Serif 4 font.
-pub(crate) mod source_serif_4 {
-    /// The file `SourceSerif4-Regular.ttf.woff2`, the Regular variant of the Source Serif 4 font in
-    /// woff2.
-    pub(crate) static REGULAR: &[u8] =
-        include_bytes!("static/fonts/SourceSerif4-Regular.ttf.woff2");
-
-    /// The file `SourceSerif4-Bold.ttf.woff2`, the Bold variant of the Source Serif 4 font in
-    /// woff2.
-    pub(crate) static BOLD: &[u8] = include_bytes!("static/fonts/SourceSerif4-Bold.ttf.woff2");
-
-    /// The file `SourceSerif4-It.ttf.woff2`, the Italic variant of the Source Serif 4 font in
-    /// woff2.
-    pub(crate) static ITALIC: &[u8] = include_bytes!("static/fonts/SourceSerif4-It.ttf.woff2");
-
-    /// The file `SourceSerif4-LICENSE.txt`, the license text for the Source Serif 4 font.
-    pub(crate) static LICENSE: &[u8] = include_bytes!("static/fonts/SourceSerif4-LICENSE.md");
+/// The Display implementation for a StaticFile outputs its filename. This makes it
+/// convenient to interpolate static files into HTML templates.
+impl fmt::Display for StaticFile {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}", self.output_filename().display())
+    }
 }
 
-/// Files related to the Source Code Pro font.
-pub(crate) mod source_code_pro {
-    /// The file `SourceCodePro-Regular.ttf.woff2`, the Regular variant of the Source Code Pro font
-    /// in woff2.
-    pub(crate) static REGULAR: &[u8] =
-        include_bytes!("static/fonts/SourceCodePro-Regular.ttf.woff2");
-
-    /// The file `SourceCodePro-Semibold.ttf.woff2`, the Semibold variant of the Source Code Pro
-    /// font in woff2.
-    pub(crate) static SEMIBOLD: &[u8] =
-        include_bytes!("static/fonts/SourceCodePro-Semibold.ttf.woff2");
-
-    /// The file `SourceCodePro-It.ttf.woff2`, the Italic variant of the Source Code Pro font in
-    /// woff2.
-    pub(crate) static ITALIC: &[u8] = include_bytes!("static/fonts/SourceCodePro-It.ttf.woff2");
-
-    /// The file `SourceCodePro-LICENSE.txt`, the license text of the Source Code Pro font.
-    pub(crate) static LICENSE: &[u8] = include_bytes!("static/fonts/SourceCodePro-LICENSE.txt");
+/// Insert the provided suffix into a filename just before the extension.
+pub(crate) fn suffix_path(filename: &str, suffix: &str) -> PathBuf {
+    // We use splitn vs Path::extension here because we might get a filename
+    // like `style.min.css` and we want to process that into
+    // `style-suffix.min.css`.  Path::extension would just return `css`
+    // which would result in `style.min-suffix.css` which isn't what we
+    // want.
+    let (base, ext) = filename.split_once('.').unwrap();
+    let filename = format!("{}{}.{}", base, suffix, ext);
+    filename.into()
 }
 
-/// Files related to the Nanum Barun Gothic font.
-///
-/// These files are used to avoid some legacy CJK serif fonts in Windows.
-///
-/// Note that the Noto Sans KR font, which was used previously but was not very readable on Windows,
-/// has been replaced by the Nanum Barun Gothic font. This is due to Windows' implementation of font
-/// rendering that distorts OpenType fonts too much.
-///
-/// The font files were generated with these commands:
-///
-/// ```sh
-/// pyftsubset NanumBarunGothic.ttf \
-/// --unicodes=U+AC00-D7AF,U+1100-11FF,U+3130-318F,U+A960-A97F,U+D7B0-D7FF \
-/// --output-file=NanumBarunGothic.ttf.woff2 --flavor=woff2
-/// ```
-pub(crate) mod nanum_barun_gothic {
-    /// The file `NanumBarunGothic.ttf.woff2`, the Regular variant of the Nanum Barun Gothic font.
-    pub(crate) static REGULAR: &[u8] = include_bytes!("static/fonts/NanumBarunGothic.ttf.woff2");
-
-    /// The file `NanumBarunGothic-LICENSE.txt`, the license text of the Nanum Barun Gothic font.
-    pub(crate) static LICENSE: &[u8] = include_bytes!("static/fonts/NanumBarunGothic-LICENSE.txt");
+pub(crate) fn static_filename(filename: &str, contents: &[u8]) -> PathBuf {
+    let filename = filename.rsplit("/").next().unwrap();
+    suffix_path(filename, &static_suffix(contents))
 }
 
-/// Files related to the sidebar in rustdoc sources.
-pub(crate) mod sidebar {
-    /// File script to handle sidebar.
-    pub(crate) static SOURCE_SCRIPT: &str = include_str!("static/js/source-script.js");
+fn static_suffix(bytes: &[u8]) -> String {
+    let mut hasher = FxHasher::default();
+    hasher.write(bytes);
+    format!("-{:016x}", hasher.finish())
 }
+
+macro_rules! static_files {
+    ($($field:ident => $file_path:literal,)+) => {
+        pub(crate) struct StaticFiles {
+            $(pub $field: StaticFile,)+
+        }
+
+        pub(crate) static STATIC_FILES: std::sync::LazyLock<StaticFiles> = std::sync::LazyLock::new(|| StaticFiles {
+            $($field: StaticFile::new($file_path, include_bytes!($file_path)),)+
+        });
+
+        pub(crate) fn for_each<E>(f: impl Fn(&StaticFile) -> Result<(), E>) -> Result<(), E> {
+            for sf in [
+            $(&STATIC_FILES.$field,)+
+            ] {
+                f(sf)?
+            }
+            Ok(())
+        }
+    }
+}
+
+static_files! {
+    rustdoc_css => "static/css/rustdoc.css",
+    settings_css => "static/css/settings.css",
+    noscript_css => "static/css/noscript.css",
+    normalize_css => "static/css/normalize.css",
+    main_js => "static/js/main.js",
+    search_js => "static/js/search.js",
+    settings_js => "static/js/settings.js",
+    source_script_js => "static/js/source-script.js",
+    storage_js => "static/js/storage.js",
+    scrape_examples_js => "static/js/scrape-examples.js",
+    wheel_svg => "static/images/wheel.svg",
+    clipboard_svg => "static/images/clipboard.svg",
+    down_arrow_svg => "static/images/down-arrow.svg",
+    toggle_minus_png => "static/images/toggle-minus.svg",
+    toggle_plus_png => "static/images/toggle-plus.svg",
+    copyright => "static/COPYRIGHT.txt",
+    license_apache => "static/LICENSE-APACHE.txt",
+    license_mit => "static/LICENSE-MIT.txt",
+    rust_logo_svg => "static/images/rust-logo.svg",
+    rust_favicon_svg => "static/images/favicon.svg",
+    rust_favicon_png_16 => "static/images/favicon-16x16.png",
+    rust_favicon_png_32 => "static/images/favicon-32x32.png",
+    theme_light_css => "static/css/themes/light.css",
+    theme_dark_css => "static/css/themes/dark.css",
+    theme_ayu_css => "static/css/themes/ayu.css",
+    fira_sans_regular => "static/fonts/FiraSans-Regular.woff2",
+    fira_sans_medium => "static/fonts/FiraSans-Medium.woff2",
+    fira_sans_license => "static/fonts/FiraSans-LICENSE.txt",
+    source_serif_4_regular => "static/fonts/SourceSerif4-Regular.ttf.woff2",
+    source_serif_4_bold => "static/fonts/SourceSerif4-Bold.ttf.woff2",
+    source_serif_4_italic => "static/fonts/SourceSerif4-It.ttf.woff2",
+    source_serif_4_license => "static/fonts/SourceSerif4-LICENSE.md",
+    source_code_pro_regular => "static/fonts/SourceCodePro-Regular.ttf.woff2",
+    source_code_pro_semibold => "static/fonts/SourceCodePro-Semibold.ttf.woff2",
+    source_code_pro_italic => "static/fonts/SourceCodePro-It.ttf.woff2",
+    source_code_pro_license => "static/fonts/SourceCodePro-LICENSE.txt",
+    nanum_barun_gothic_regular => "static/fonts/NanumBarunGothic.ttf.woff2",
+    nanum_barun_gothic_license => "static/fonts/NanumBarunGothic-LICENSE.txt",
+}
+
+pub(crate) static SCRAPE_EXAMPLES_HELP_MD: &str = include_str!("static/js/scrape-examples.js");
diff --git a/src/librustdoc/html/templates/page.html b/src/librustdoc/html/templates/page.html
index 2a111f94e507..4efcfc510a25 100644
--- a/src/librustdoc/html/templates/page.html
+++ b/src/librustdoc/html/templates/page.html
@@ -7,48 +7,44 @@
     <meta name="description" content="{{page.description}}"> {#- -#}
     <meta name="keywords" content="{{page.keywords}}"> {#- -#}
     <title>{{page.title}}</title> {#- -#}
-    <link rel="preload" as="font" type="font/woff2" crossorigin href="{{static_root_path|safe}}SourceSerif4-Regular.ttf.woff2"> {#- -#}
-    <link rel="preload" as="font" type="font/woff2" crossorigin href="{{static_root_path|safe}}FiraSans-Regular.woff2"> {#- -#}
-    <link rel="preload" as="font" type="font/woff2" crossorigin href="{{static_root_path|safe}}FiraSans-Medium.woff2"> {#- -#}
-    <link rel="preload" as="font" type="font/woff2" crossorigin href="{{static_root_path|safe}}SourceCodePro-Regular.ttf.woff2"> {#- -#}
-    <link rel="preload" as="font" type="font/woff2" crossorigin href="{{static_root_path|safe}}SourceSerif4-Bold.ttf.woff2"> {#- -#}
-    <link rel="preload" as="font" type="font/woff2" crossorigin href="{{static_root_path|safe}}SourceCodePro-Semibold.ttf.woff2"> {#- -#}
+    <link rel="preload" as="font" type="font/woff2" crossorigin href="{{static_root_path|safe}}{{files.source_serif_4_regular}}"> {#- -#}
+    <link rel="preload" as="font" type="font/woff2" crossorigin href="{{static_root_path|safe}}{{files.fira_sans_regular}}"> {#- -#}
+    <link rel="preload" as="font" type="font/woff2" crossorigin href="{{static_root_path|safe}}{{files.fira_sans_medium}}"> {#- -#}
+    <link rel="preload" as="font" type="font/woff2" crossorigin href="{{static_root_path|safe}}{{files.source_code_pro_regular}}"> {#- -#}
+    <link rel="preload" as="font" type="font/woff2" crossorigin href="{{static_root_path|safe}}{{files.source_serif_4_bold}}"> {#- -#}
+    <link rel="preload" as="font" type="font/woff2" crossorigin href="{{static_root_path|safe}}{{files.source_code_pro_semibold}}"> {#- -#}
     <link rel="stylesheet" {# -#}
-          href="{{static_root_path|safe}}normalize{{page.resource_suffix}}.css"> {#- -#}
+          href="{{static_root_path|safe}}{{files.normalize_css}}"> {#- -#}
     <link rel="stylesheet" {# -#}
-          href="{{static_root_path|safe}}rustdoc{{page.resource_suffix}}.css" {# -#}
+          href="{{static_root_path|safe}}{{files.rustdoc_css}}" {# -#}
           id="mainThemeStyle"> {#- -#}
+    <link rel="stylesheet" id="themeStyle" href="{{static_root_path|safe}}{{files.theme_light_css}}"> {#- -#}
+    <link rel="stylesheet" disabled href="{{static_root_path|safe}}{{files.theme_dark_css}}"> {#- -#}
+    <link rel="stylesheet" disabled href="{{static_root_path|safe}}{{files.theme_ayu_css}}"> {#- -#}
     {%- for theme in themes -%}
-        <link rel="stylesheet" {# -#}
-            href="{{static_root_path|safe}}{{theme}}{{page.resource_suffix}}.css" {# -#}
-        {%- if theme == "light" -%}
-            id="themeStyle"
-        {%- else -%}
-            disabled
-        {%- endif -%}
-        >
+        <link rel="stylesheet" disabled href="{{page.root_path|safe}}{{theme}}{{page.resource_suffix}}.css"> {#- -#}
     {%- endfor -%}
     <script id="default-settings" {# -#}
       {% for (k, v) in layout.default_settings %}
         data-{{k}}="{{v}}"
       {%- endfor -%}
     ></script> {#- -#}
-    <script src="{{static_root_path|safe}}storage{{page.resource_suffix}}.js"></script> {#- -#}
+    <script src="{{static_root_path|safe}}{{files.storage_js}}"></script> {#- -#}
     {%- if page.css_class.contains("crate") -%}
     <script defer src="{{page.root_path|safe}}crates{{page.resource_suffix}}.js"></script> {#- -#}
     {%- else if page.css_class == "source" -%}
-    <script defer src="{{static_root_path|safe}}source-script{{page.resource_suffix}}.js"></script> {#- -#}
+    <script defer src="{{static_root_path|safe}}{{files.source_script_js}}"></script> {#- -#}
     <script defer src="{{page.root_path|safe}}source-files{{page.resource_suffix}}.js"></script> {#- -#}
     {%- else if !page.css_class.contains("mod") -%}
     <script defer src="sidebar-items{{page.resource_suffix}}.js"></script> {#- -#}
     {%- endif -%}
-    <script defer src="{{static_root_path|safe}}main{{page.resource_suffix}}.js"></script> {#- -#}
+    <script defer src="{{static_root_path|safe}}{{files.main_js}}"></script> {#- -#}
     {%- if layout.scrape_examples_extension -%}
-    <script defer src="{{page.root_path|safe}}scrape-examples{{page.resource_suffix}}.js"></script> {#- -#}
+    <script defer src="{{page.root_path|safe}}{{files.scrape_examples_js}}"></script> {#- -#}
     {%- endif -%}
     <noscript> {#- -#}
         <link rel="stylesheet" {# -#}
-           href="{{static_root_path|safe}}noscript{{page.resource_suffix}}.css"> {#- -#}
+           href="{{static_root_path|safe}}{{files.noscript_css}}"> {#- -#}
     </noscript> {#- -#}
     {%- if layout.css_file_extension.is_some() -%}
         <link rel="stylesheet" {# -#}
@@ -58,11 +54,11 @@
         <link rel="icon" href="{{layout.favicon}}"> {#- -#}
     {%- else -%}
         <link rel="alternate icon" type="image/png" {# -#}
-            href="{{static_root_path|safe}}favicon-16x16{{page.resource_suffix}}.png"> {#- -#}
+            href="{{static_root_path|safe}}{{files.rust_favicon_png_16}}"> {#- -#}
         <link rel="alternate icon" type="image/png" {# -#}
-            href="{{static_root_path|safe}}favicon-32x32{{page.resource_suffix}}.png"> {#- -#}
+            href="{{static_root_path|safe}}{{files.rust_favicon_png_32}}"> {#- -#}
         <link rel="icon" type="image/svg+xml" {# -#}
-            href="{{static_root_path|safe}}favicon{{page.resource_suffix}}.svg"> {#- -#}
+            href="{{static_root_path|safe}}{{files.rust_favicon_svg}}"> {#- -#}
     {%- endif -%}
     {{- layout.external_html.in_header|safe -}}
 </head> {#- -#}
@@ -81,7 +77,7 @@
             {%- if !layout.logo.is_empty() -%}
                 <img src="{{layout.logo}}" alt="logo"> {#- -#}
             {%- else -%}
-                <img class="rust-logo" src="{{static_root_path|safe}}rust-logo{{page.resource_suffix}}.svg" alt="logo"> {#- -#}
+                <img class="rust-logo" src="{{static_root_path|safe}}{{files.rust_logo_svg}}" alt="logo"> {#- -#}
             {%- endif -%}
             </div> {#- -#}
         </a> {#- -#}
@@ -89,15 +85,17 @@
     </nav> {#- -#}
     {%- endif -%}
     <nav class="sidebar"> {#- -#}
+        {%- if page.css_class != "source" -%}
         <a class="sidebar-logo" href="{{page.root_path|safe}}{{krate_with_trailing_slash|safe}}index.html"> {#- -#}
             <div class="logo-container"> {#- -#}
                 {%- if !layout.logo.is_empty()  %}
                     <img src="{{layout.logo}}" alt="logo"> {#- -#}
                 {%- else -%}
-                    <img class="rust-logo" src="{{static_root_path|safe}}rust-logo{{page.resource_suffix}}.svg" alt="logo"> {#- -#}
+                    <img class="rust-logo" src="{{static_root_path|safe}}{{files.rust_logo_svg}}" alt="logo"> {#- -#}
                 {%- endif -%}
             </div> {#- -#}
         </a> {#- -#}
+        {%- endif -%}
         {{- sidebar|safe -}}
     </nav> {#- -#}
     <main> {#- -#}
@@ -108,29 +106,27 @@
                     {%- if !layout.logo.is_empty()  %}
                         <img src="{{layout.logo}}" alt="logo"> {#- -#}
                     {%- else -%}
-                        <img class="rust-logo" src="{{static_root_path|safe}}rust-logo{{page.resource_suffix}}.svg" alt="logo"> {#- -#}
+                        <img class="rust-logo" src="{{static_root_path|safe}}{{files.rust_logo_svg}}" alt="logo"> {#- -#}
                     {%- endif -%}
                 </a> {#- -#}
                 {%- endif -%}
                 <form class="search-form"> {#- -#}
-                    <div class="search-container"> {#- -#}
-                        <span></span> {#- This empty span is a hacky fix for Safari - See #93184 -#}
-                        <input {# -#}
-                            class="search-input" {# -#}
-                            name="search" {# -#}
-                            autocomplete="off" {# -#}
-                            spellcheck="false" {# -#}
-                            placeholder="Click or press ‘S’ to search, ‘?’ for more options…" {# -#}
-                            type="search"> {#- -#}
-                        <div id="help-button" title="help" tabindex="-1"> {#- -#}
-                            <a href="{{page.root_path|safe}}help.html">?</a> {#- -#}
-                        </div> {#- -#}
-                        <div id="settings-menu" tabindex="-1"> {#- -#}
-                            <a href="{{page.root_path|safe}}settings.html" title="settings"> {#- -#}
-                                <img width="22" height="22" alt="Change settings" {# -#}
-                                 src="{{static_root_path|safe}}wheel{{page.resource_suffix}}.svg"> {#- -#}
-                            </a> {#- -#}
-                        </div> {#- -#}
+                    <span></span> {#- This empty span is a hacky fix for Safari - See #93184 -#}
+                    <input {# -#}
+                        class="search-input" {# -#}
+                        name="search" {# -#}
+                        autocomplete="off" {# -#}
+                        spellcheck="false" {# -#}
+                        placeholder="Click or press ‘S’ to search, ‘?’ for more options…" {# -#}
+                        type="search"> {#- -#}
+                    <div id="help-button" title="help" tabindex="-1"> {#- -#}
+                        <a href="{{page.root_path|safe}}help.html">?</a> {#- -#}
+                    </div> {#- -#}
+                    <div id="settings-menu" tabindex="-1"> {#- -#}
+                        <a href="{{page.root_path|safe}}settings.html" title="settings"> {#- -#}
+                            <img width="22" height="22" alt="Change settings" {# -#}
+                            src="{{static_root_path|safe}}{{files.wheel_svg}}"> {#- -#}
+                        </a> {#- -#}
                     </div> {#- -#}
                 </form> {#- -#}
             </nav> {#- -#}
@@ -140,10 +136,14 @@
     {{- layout.external_html.after_content|safe -}}
     <div id="rustdoc-vars" {# -#}
          data-root-path="{{page.root_path|safe}}" {# -#}
+         data-static-root-path="{{static_root_path|safe}}" {# -#}
          data-current-crate="{{layout.krate}}" {# -#}
          data-themes="{{themes|join(",") }}" {# -#}
          data-resource-suffix="{{page.resource_suffix}}" {# -#}
          data-rustdoc-version="{{rustdoc_version}}" {# -#}
+         data-search-js="{{files.search_js}}" {# -#}
+         data-settings-js="{{files.settings_js}}" {# -#}
+         data-settings-css="{{files.settings_css}}" {# -#}
     > {#- -#}
     </div> {#- -#}
 </body> {#- -#}
diff --git a/src/librustdoc/html/templates/print_item.html b/src/librustdoc/html/templates/print_item.html
index b6ce3ea3dee9..611d124d4b91 100644
--- a/src/librustdoc/html/templates/print_item.html
+++ b/src/librustdoc/html/templates/print_item.html
@@ -7,7 +7,7 @@
         {%- endfor -%}
         <a class="{{item_type}}" href="#">{{name}}</a> {#- -#}
         <button id="copy-path" onclick="copy_path(this)" title="Copy item path to clipboard"> {#- -#}
-            <img src="{{static_root_path|safe}}clipboard{{page.resource_suffix}}.svg" {# -#}
+        <img src="{{static_root_path|safe}}{{clipboard_svg}}" {# -#}
                 width="19" height="18" {# -#}
                 alt="Copy item path"> {#- -#}
         </button> {#- -#}
@@ -21,8 +21,8 @@
                 <a class="srclink" href="{{href|safe}}">source</a> · {# -#}
             {%- else -%}
         {%- endmatch -%}
-        <a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs"> {#- -#}
-            [<span class="inner">&#x2212;</span>] {#- -#}
-        </a> {#- -#}
+        <button id="toggle-all-docs" title="collapse all docs"> {#- -#}
+            [<span>&#x2212;</span>] {#- -#}
+        </button> {#- -#}
     </span> {#- -#}
 </div> {#- -#}
diff --git a/src/librustdoc/json/conversions.rs b/src/librustdoc/json/conversions.rs
index cdf59cdd3284..acfbd072121a 100644
--- a/src/librustdoc/json/conversions.rs
+++ b/src/librustdoc/json/conversions.rs
@@ -48,7 +48,8 @@ impl JsonRenderer<'_> {
             .map(rustc_ast_pretty::pprust::attribute_to_string)
             .collect();
         let span = item.span(self.tcx);
-        let clean::Item { name, attrs: _, kind: _, visibility, item_id, cfg: _ } = item;
+        let visibility = item.visibility(self.tcx);
+        let clean::Item { name, attrs: _, kind: _, item_id, cfg: _, .. } = item;
         let inner = match *item.kind {
             clean::KeywordItem => return None,
             clean::StrippedItem(ref inner) => {
@@ -99,13 +100,12 @@ impl JsonRenderer<'_> {
         }
     }
 
-    fn convert_visibility(&self, v: clean::Visibility) -> Visibility {
-        use clean::Visibility::*;
+    fn convert_visibility(&self, v: Option<ty::Visibility<DefId>>) -> Visibility {
         match v {
-            Public => Visibility::Public,
-            Inherited => Visibility::Default,
-            Restricted(did) if did.is_crate_root() => Visibility::Crate,
-            Restricted(did) => Visibility::Restricted {
+            None => Visibility::Default,
+            Some(ty::Visibility::Public) => Visibility::Public,
+            Some(ty::Visibility::Restricted(did)) if did.is_crate_root() => Visibility::Crate,
+            Some(ty::Visibility::Restricted(did)) => Visibility::Restricted {
                 parent: from_item_id(did.into(), self.tcx),
                 path: self.tcx.def_path(did).to_string_no_crate_verbose(),
             },
@@ -283,7 +283,7 @@ fn from_clean_item(item: clean::Item, tcx: TyCtxt<'_>) -> ItemEnum {
             ItemEnum::AssocConst { type_: ty.into_tcx(tcx), default: Some(default.expr(tcx)) }
         }
         TyAssocTypeItem(g, b) => ItemEnum::AssocType {
-            generics: (*g).into_tcx(tcx),
+            generics: g.into_tcx(tcx),
             bounds: b.into_tcx(tcx),
             default: None,
         },
@@ -485,7 +485,7 @@ impl FromWithTcx<clean::Type> for Type {
             BareFunction(f) => Type::FunctionPointer(Box::new((*f).into_tcx(tcx))),
             Tuple(t) => Type::Tuple(t.into_tcx(tcx)),
             Slice(t) => Type::Slice(Box::new((*t).into_tcx(tcx))),
-            Array(t, s) => Type::Array { type_: Box::new((*t).into_tcx(tcx)), len: s },
+            Array(t, s) => Type::Array { type_: Box::new((*t).into_tcx(tcx)), len: s.to_string() },
             ImplTrait(g) => Type::ImplTrait(g.into_tcx(tcx)),
             Infer => Type::Infer,
             RawPointer(mutability, type_) => Type::RawPointer {
@@ -674,7 +674,7 @@ impl FromWithTcx<clean::Variant> for Variant {
 impl FromWithTcx<clean::Discriminant> for Discriminant {
     fn from_tcx(disr: clean::Discriminant, tcx: TyCtxt<'_>) -> Self {
         Discriminant {
-            // expr is only none if going throught the inlineing path, which gets
+            // expr is only none if going through the inlineing path, which gets
             // `rustc_middle` types, not `rustc_hir`, but because JSON never inlines
             // the expr is always some.
             expr: disr.expr(tcx).unwrap(),
diff --git a/src/librustdoc/json/mod.rs b/src/librustdoc/json/mod.rs
index d13efe6c113b..beb705400913 100644
--- a/src/librustdoc/json/mod.rs
+++ b/src/librustdoc/json/mod.rs
@@ -277,7 +277,7 @@ impl<'tcx> FormatRenderer<'tcx> for JsonRenderer<'tcx> {
 
         let e = ExternalCrate { crate_num: LOCAL_CRATE };
 
-        // FIXME(adotinthevoid): Remove this, as it's not consistant with not
+        // FIXME(adotinthevoid): Remove this, as it's not consistent with not
         // inlining foreign items.
         let foreign_trait_items = self.get_trait_items();
         let mut index = (*self.index).clone().into_inner();
diff --git a/src/librustdoc/lib.rs b/src/librustdoc/lib.rs
index 793061a9f7a0..1982c066b6ff 100644
--- a/src/librustdoc/lib.rs
+++ b/src/librustdoc/lib.rs
@@ -154,7 +154,6 @@ pub fn main() {
         }
     }
 
-    rustc_driver::set_sigpipe_handler();
     rustc_driver::install_ice_hook();
 
     // When using CI artifacts (with `download_stage1 = true`), tracing is unconditionally built
@@ -470,9 +469,6 @@ fn opts() -> Vec<RustcOptGroup> {
         stable("json", |o| {
             o.optopt("", "json", "Configure the structure of JSON diagnostics", "CONFIG")
         }),
-        unstable("disable-minification", |o| {
-            o.optflagmulti("", "disable-minification", "Disable minification applied on JS files")
-        }),
         stable("allow", |o| o.optmulti("A", "allow", "Set lint allowed", "LINT")),
         stable("warn", |o| o.optmulti("W", "warn", "Set lint warnings", "LINT")),
         stable("force-warn", |o| o.optmulti("", "force-warn", "Set lint force-warn", "LINT")),
@@ -611,6 +607,7 @@ fn opts() -> Vec<RustcOptGroup> {
             )
         }),
         // deprecated / removed options
+        unstable("disable-minification", |o| o.optflagmulti("", "disable-minification", "removed")),
         stable("plugin-path", |o| {
             o.optmulti(
                 "",
diff --git a/src/librustdoc/passes/check_doc_test_visibility.rs b/src/librustdoc/passes/check_doc_test_visibility.rs
index 15982b40944e..057d2fdd9d5f 100644
--- a/src/librustdoc/passes/check_doc_test_visibility.rs
+++ b/src/librustdoc/passes/check_doc_test_visibility.rs
@@ -56,7 +56,7 @@ impl crate::doctest::Tester for Tests {
 }
 
 pub(crate) fn should_have_doc_example(cx: &DocContext<'_>, item: &clean::Item) -> bool {
-    if !cx.cache.access_levels.is_public(item.item_id.expect_def_id())
+    if !cx.cache.effective_visibilities.is_directly_public(cx.tcx, item.item_id.expect_def_id())
         || matches!(
             *item.kind,
             clean::StructFieldItem(_)
@@ -130,7 +130,7 @@ pub(crate) fn look_for_tests<'tcx>(cx: &DocContext<'tcx>, dox: &str, item: &Item
             );
         }
     } else if tests.found_tests > 0
-        && !cx.cache.access_levels.is_exported(item.item_id.expect_def_id())
+        && !cx.cache.effective_visibilities.is_exported(cx.tcx, item.item_id.expect_def_id())
     {
         cx.tcx.struct_span_lint_hir(
             crate::lint::PRIVATE_DOC_TESTS,
diff --git a/src/librustdoc/passes/collect_intra_doc_links.rs b/src/librustdoc/passes/collect_intra_doc_links.rs
index 3513c13d522f..37a28b6b7bd8 100644
--- a/src/librustdoc/passes/collect_intra_doc_links.rs
+++ b/src/librustdoc/passes/collect_intra_doc_links.rs
@@ -402,6 +402,7 @@ impl<'a, 'tcx> LinkCollector<'a, 'tcx> {
             })
             .and_then(|self_id| match tcx.def_kind(self_id) {
                 DefKind::Impl => self.def_id_to_res(self_id),
+                DefKind::Use => None,
                 def_kind => Some(Res::Def(def_kind, self_id)),
             })
     }
@@ -1202,8 +1203,8 @@ impl LinkCollector<'_, '_> {
                 item.item_id.expect_def_id().as_local().map(|src_id| (src_id, dst_id))
             })
         {
-            if self.cx.tcx.privacy_access_levels(()).is_exported(src_id)
-                && !self.cx.tcx.privacy_access_levels(()).is_exported(dst_id)
+            if self.cx.tcx.effective_visibilities(()).is_exported(src_id)
+                && !self.cx.tcx.effective_visibilities(()).is_exported(dst_id)
             {
                 privacy_error(self.cx, diag_info, path_str);
             }
@@ -1772,7 +1773,6 @@ fn resolution_failure(
 
                     // Otherwise, it must be an associated item or variant
                     let res = partial_res.expect("None case was handled by `last_found_module`");
-                    let name = res.name(tcx);
                     let kind = match res {
                         Res::Def(kind, _) => Some(kind),
                         Res::Primitive(_) => None,
@@ -1814,6 +1814,7 @@ fn resolution_failure(
                     } else {
                         "associated item"
                     };
+                    let name = res.name(tcx);
                     let note = format!(
                         "the {} `{}` has no {} named `{}`",
                         res.descr(),
@@ -1893,7 +1894,7 @@ fn disambiguator_error(
     diag_info.link_range = disambiguator_range;
     report_diagnostic(cx.tcx, BROKEN_INTRA_DOC_LINKS, msg, &diag_info, |diag, _sp| {
         let msg = format!(
-            "see {}/rustdoc/linking-to-items-by-name.html#namespaces-and-disambiguators for more info about disambiguators",
+            "see {}/rustdoc/write-documentation/linking-to-items-by-name.html#namespaces-and-disambiguators for more info about disambiguators",
             crate::DOC_RUST_LANG_ORG_CHANNEL
         );
         diag.note(&msg);
diff --git a/src/librustdoc/passes/collect_intra_doc_links/early.rs b/src/librustdoc/passes/collect_intra_doc_links/early.rs
index d121a3e2aa4a..1b373cfe5bb7 100644
--- a/src/librustdoc/passes/collect_intra_doc_links/early.rs
+++ b/src/librustdoc/passes/collect_intra_doc_links/early.rs
@@ -354,7 +354,14 @@ impl Visitor<'_> for EarlyDocLinkResolver<'_, '_> {
             self.parent_scope.module = old_module;
         } else {
             match &item.kind {
-                ItemKind::Impl(box ast::Impl { of_trait: Some(..), .. }) => {
+                ItemKind::Impl(box ast::Impl { of_trait: Some(trait_ref), .. }) => {
+                    if let Some(partial_res) = self.resolver.get_partial_res(trait_ref.ref_id)
+                        && let Some(res) = partial_res.full_res()
+                        && let Some(trait_def_id) = res.opt_def_id()
+                        && !trait_def_id.is_local()
+                        && self.visited_mods.insert(trait_def_id) {
+                        self.resolve_doc_links_extern_impl(trait_def_id, false);
+                    }
                     self.all_trait_impls.push(self.resolver.local_def_id(item.id).to_def_id());
                 }
                 ItemKind::MacroDef(macro_def) if macro_def.macro_rules => {
diff --git a/src/librustdoc/passes/html_tags.rs b/src/librustdoc/passes/html_tags.rs
index 67fc71665ccf..a89ed7c7ed45 100644
--- a/src/librustdoc/passes/html_tags.rs
+++ b/src/librustdoc/passes/html_tags.rs
@@ -184,7 +184,60 @@ fn extract_html_tag(
                     }
                     drop_tag(tags, tag_name, r, f);
                 } else {
-                    tags.push((tag_name, r));
+                    let mut is_self_closing = false;
+                    let mut quote_pos = None;
+                    if c != '>' {
+                        let mut quote = None;
+                        let mut after_eq = false;
+                        for (i, c) in text[pos..].char_indices() {
+                            if !c.is_whitespace() {
+                                if let Some(q) = quote {
+                                    if c == q {
+                                        quote = None;
+                                        quote_pos = None;
+                                        after_eq = false;
+                                    }
+                                } else if c == '>' {
+                                    break;
+                                } else if c == '/' && !after_eq {
+                                    is_self_closing = true;
+                                } else {
+                                    if is_self_closing {
+                                        is_self_closing = false;
+                                    }
+                                    if (c == '"' || c == '\'') && after_eq {
+                                        quote = Some(c);
+                                        quote_pos = Some(pos + i);
+                                    } else if c == '=' {
+                                        after_eq = true;
+                                    }
+                                }
+                            } else if quote.is_none() {
+                                after_eq = false;
+                            }
+                        }
+                    }
+                    if let Some(quote_pos) = quote_pos {
+                        let qr = Range { start: quote_pos, end: quote_pos };
+                        f(
+                            &format!("unclosed quoted HTML attribute on tag `{}`", tag_name),
+                            &qr,
+                            false,
+                        );
+                    }
+                    if is_self_closing {
+                        // https://html.spec.whatwg.org/#parse-error-non-void-html-element-start-tag-with-trailing-solidus
+                        let valid = ALLOWED_UNCLOSED.contains(&&tag_name[..])
+                            || tags.iter().take(pos + 1).any(|(at, _)| {
+                                let at = at.to_lowercase();
+                                at == "svg" || at == "math"
+                            });
+                        if !valid {
+                            f(&format!("invalid self-closing HTML tag `{}`", tag_name), &r, false);
+                        }
+                    } else {
+                        tags.push((tag_name, r));
+                    }
                 }
             }
             break;
diff --git a/src/librustdoc/passes/strip_hidden.rs b/src/librustdoc/passes/strip_hidden.rs
index 9914edf3036e..e07a788a72a4 100644
--- a/src/librustdoc/passes/strip_hidden.rs
+++ b/src/librustdoc/passes/strip_hidden.rs
@@ -27,6 +27,7 @@ pub(crate) fn strip_hidden(krate: clean::Crate, cx: &mut DocContext<'_>) -> clea
 
     // strip all impls referencing stripped items
     let mut stripper = ImplStripper {
+        tcx: cx.tcx,
         retained: &retained,
         cache: &cx.cache,
         is_json_output,
diff --git a/src/librustdoc/passes/strip_priv_imports.rs b/src/librustdoc/passes/strip_priv_imports.rs
index 85be8fa109a7..3bac5a8e5d74 100644
--- a/src/librustdoc/passes/strip_priv_imports.rs
+++ b/src/librustdoc/passes/strip_priv_imports.rs
@@ -11,6 +11,6 @@ pub(crate) const STRIP_PRIV_IMPORTS: Pass = Pass {
     description: "strips all private import statements (`use`, `extern crate`) from a crate",
 };
 
-pub(crate) fn strip_priv_imports(krate: clean::Crate, _: &mut DocContext<'_>) -> clean::Crate {
-    ImportStripper.fold_crate(krate)
+pub(crate) fn strip_priv_imports(krate: clean::Crate, cx: &mut DocContext<'_>) -> clean::Crate {
+    ImportStripper { tcx: cx.tcx }.fold_crate(krate)
 }
diff --git a/src/librustdoc/passes/strip_private.rs b/src/librustdoc/passes/strip_private.rs
index f3aa3c7ce245..8fc42462de96 100644
--- a/src/librustdoc/passes/strip_private.rs
+++ b/src/librustdoc/passes/strip_private.rs
@@ -23,15 +23,17 @@ pub(crate) fn strip_private(mut krate: clean::Crate, cx: &mut DocContext<'_>) ->
     {
         let mut stripper = Stripper {
             retained: &mut retained,
-            access_levels: &cx.cache.access_levels,
+            effective_visibilities: &cx.cache.effective_visibilities,
             update_retained: true,
             is_json_output,
+            tcx: cx.tcx,
         };
-        krate = ImportStripper.fold_crate(stripper.fold_crate(krate));
+        krate = ImportStripper { tcx: cx.tcx }.fold_crate(stripper.fold_crate(krate));
     }
 
     // strip all impls referencing private items
     let mut stripper = ImplStripper {
+        tcx: cx.tcx,
         retained: &retained,
         cache: &cx.cache,
         is_json_output,
diff --git a/src/librustdoc/passes/stripper.rs b/src/librustdoc/passes/stripper.rs
index a9d768f0149d..995fb5dcc1c8 100644
--- a/src/librustdoc/passes/stripper.rs
+++ b/src/librustdoc/passes/stripper.rs
@@ -1,17 +1,20 @@
 //! A collection of utility functions for the `strip_*` passes.
 use rustc_hir::def_id::DefId;
-use rustc_middle::middle::privacy::AccessLevels;
+use rustc_middle::ty::{TyCtxt, Visibility};
+use rustc_span::symbol::sym;
 use std::mem;
 
-use crate::clean::{self, Item, ItemId, ItemIdSet};
+use crate::clean::{self, Item, ItemId, ItemIdSet, NestedAttributesExt};
 use crate::fold::{strip_item, DocFolder};
 use crate::formats::cache::Cache;
+use crate::visit_lib::RustdocEffectiveVisibilities;
 
-pub(crate) struct Stripper<'a> {
+pub(crate) struct Stripper<'a, 'tcx> {
     pub(crate) retained: &'a mut ItemIdSet,
-    pub(crate) access_levels: &'a AccessLevels<DefId>,
+    pub(crate) effective_visibilities: &'a RustdocEffectiveVisibilities,
     pub(crate) update_retained: bool,
     pub(crate) is_json_output: bool,
+    pub(crate) tcx: TyCtxt<'tcx>,
 }
 
 // We need to handle this differently for the JSON output because some non exported items could
@@ -19,18 +22,19 @@ pub(crate) struct Stripper<'a> {
 // are in the public API, which is not enough.
 #[inline]
 fn is_item_reachable(
+    tcx: TyCtxt<'_>,
     is_json_output: bool,
-    access_levels: &AccessLevels<DefId>,
+    effective_visibilities: &RustdocEffectiveVisibilities,
     item_id: ItemId,
 ) -> bool {
     if is_json_output {
-        access_levels.is_reachable(item_id.expect_def_id())
+        effective_visibilities.is_reachable(tcx, item_id.expect_def_id())
     } else {
-        access_levels.is_exported(item_id.expect_def_id())
+        effective_visibilities.is_exported(tcx, item_id.expect_def_id())
     }
 }
 
-impl<'a> DocFolder for Stripper<'a> {
+impl<'a, 'tcx> DocFolder for Stripper<'a, 'tcx> {
     fn fold_item(&mut self, i: Item) -> Option<Item> {
         match *i.kind {
             clean::StrippedItem(..) => {
@@ -64,7 +68,12 @@ impl<'a> DocFolder for Stripper<'a> {
             | clean::ForeignTypeItem => {
                 let item_id = i.item_id;
                 if item_id.is_local()
-                    && !is_item_reachable(self.is_json_output, self.access_levels, item_id)
+                    && !is_item_reachable(
+                        self.tcx,
+                        self.is_json_output,
+                        self.effective_visibilities,
+                        item_id,
+                    )
                 {
                     debug!("Stripper: stripping {:?} {:?}", i.type_(), i.name);
                     return None;
@@ -72,13 +81,13 @@ impl<'a> DocFolder for Stripper<'a> {
             }
 
             clean::StructFieldItem(..) => {
-                if !i.visibility.is_public() {
+                if i.visibility(self.tcx) != Some(Visibility::Public) {
                     return Some(strip_item(i));
                 }
             }
 
             clean::ModuleItem(..) => {
-                if i.item_id.is_local() && !i.visibility.is_public() {
+                if i.item_id.is_local() && i.visibility(self.tcx) != Some(Visibility::Public) {
                     debug!("Stripper: stripping module {:?}", i.name);
                     let old = mem::replace(&mut self.update_retained, false);
                     let ret = strip_item(self.fold_item_recur(i));
@@ -144,14 +153,31 @@ impl<'a> DocFolder for Stripper<'a> {
 }
 
 /// This stripper discards all impls which reference stripped items
-pub(crate) struct ImplStripper<'a> {
+pub(crate) struct ImplStripper<'a, 'tcx> {
+    pub(crate) tcx: TyCtxt<'tcx>,
     pub(crate) retained: &'a ItemIdSet,
     pub(crate) cache: &'a Cache,
     pub(crate) is_json_output: bool,
     pub(crate) document_private: bool,
 }
 
-impl<'a> DocFolder for ImplStripper<'a> {
+impl<'a> ImplStripper<'a, '_> {
+    #[inline]
+    fn should_keep_impl(&self, item: &Item, for_def_id: DefId) -> bool {
+        if !for_def_id.is_local() || self.retained.contains(&for_def_id.into()) {
+            true
+        } else if self.is_json_output {
+            // If the "for" item is exported and the impl block isn't `#[doc(hidden)]`, then we
+            // need to keep it.
+            self.cache.effective_visibilities.is_exported(self.tcx, for_def_id)
+                && !item.attrs.lists(sym::doc).has_word(sym::hidden)
+        } else {
+            false
+        }
+    }
+}
+
+impl<'a> DocFolder for ImplStripper<'a, '_> {
     fn fold_item(&mut self, i: Item) -> Option<Item> {
         if let clean::ImplItem(ref imp) = *i.kind {
             // Impl blocks can be skipped if they are: empty; not a trait impl; and have no
@@ -167,8 +193,9 @@ impl<'a> DocFolder for ImplStripper<'a> {
                         let item_id = i.item_id;
                         item_id.is_local()
                             && !is_item_reachable(
+                                self.tcx,
                                 self.is_json_output,
-                                &self.cache.access_levels,
+                                &self.cache.effective_visibilities,
                                 item_id,
                             )
                     })
@@ -178,15 +205,17 @@ impl<'a> DocFolder for ImplStripper<'a> {
                     return None;
                 }
             }
+            // Because we don't inline in `maybe_inline_local` if the output format is JSON,
+            // we need to make a special check for JSON output: we want to keep it unless it has
+            // a `#[doc(hidden)]` attribute if the `for_` type is exported.
             if let Some(did) = imp.for_.def_id(self.cache) {
-                if did.is_local() && !imp.for_.is_assoc_ty() && !self.retained.contains(&did.into())
-                {
+                if !imp.for_.is_assoc_ty() && !self.should_keep_impl(&i, did) {
                     debug!("ImplStripper: impl item for stripped type; removing");
                     return None;
                 }
             }
             if let Some(did) = imp.trait_.as_ref().map(|t| t.def_id()) {
-                if did.is_local() && !self.retained.contains(&did.into()) {
+                if !self.should_keep_impl(&i, did) {
                     debug!("ImplStripper: impl item for stripped trait; removing");
                     return None;
                 }
@@ -194,7 +223,7 @@ impl<'a> DocFolder for ImplStripper<'a> {
             if let Some(generics) = imp.trait_.as_ref().and_then(|t| t.generics()) {
                 for typaram in generics {
                     if let Some(did) = typaram.def_id(self.cache) {
-                        if did.is_local() && !self.retained.contains(&did.into()) {
+                        if !self.should_keep_impl(&i, did) {
                             debug!(
                                 "ImplStripper: stripped item in trait's generics; removing impl"
                             );
@@ -209,12 +238,16 @@ impl<'a> DocFolder for ImplStripper<'a> {
 }
 
 /// This stripper discards all private import statements (`use`, `extern crate`)
-pub(crate) struct ImportStripper;
+pub(crate) struct ImportStripper<'tcx> {
+    pub(crate) tcx: TyCtxt<'tcx>,
+}
 
-impl DocFolder for ImportStripper {
+impl<'tcx> DocFolder for ImportStripper<'tcx> {
     fn fold_item(&mut self, i: Item) -> Option<Item> {
         match *i.kind {
-            clean::ExternCrateItem { .. } | clean::ImportItem(..) if !i.visibility.is_public() => {
+            clean::ExternCrateItem { .. } | clean::ImportItem(..)
+                if i.visibility(self.tcx) != Some(Visibility::Public) =>
+            {
                 None
             }
             _ => Some(self.fold_item_recur(i)),
diff --git a/src/librustdoc/visit_ast.rs b/src/librustdoc/visit_ast.rs
index b8522ea5d8fd..c788b9f4093f 100644
--- a/src/librustdoc/visit_ast.rs
+++ b/src/librustdoc/visit_ast.rs
@@ -7,15 +7,14 @@ use rustc_hir::def::{DefKind, Res};
 use rustc_hir::def_id::DefId;
 use rustc_hir::Node;
 use rustc_hir::CRATE_HIR_ID;
-use rustc_middle::middle::privacy::AccessLevel;
-use rustc_middle::ty::{TyCtxt, Visibility};
+use rustc_middle::ty::TyCtxt;
 use rustc_span::def_id::{CRATE_DEF_ID, LOCAL_CRATE};
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_span::Span;
 
 use std::mem;
 
-use crate::clean::{self, cfg::Cfg, AttributesExt, NestedAttributesExt};
+use crate::clean::{cfg::Cfg, AttributesExt, NestedAttributesExt};
 use crate::core;
 
 /// This module is used to store stuff from Rust's AST in a more convenient
@@ -26,8 +25,8 @@ pub(crate) struct Module<'hir> {
     pub(crate) where_inner: Span,
     pub(crate) mods: Vec<Module<'hir>>,
     pub(crate) id: hir::HirId,
-    // (item, renamed)
-    pub(crate) items: Vec<(&'hir hir::Item<'hir>, Option<Symbol>)>,
+    // (item, renamed, import_id)
+    pub(crate) items: Vec<(&'hir hir::Item<'hir>, Option<Symbol>, Option<hir::HirId>)>,
     pub(crate) foreigns: Vec<(&'hir hir::ForeignItem<'hir>, Option<Symbol>)>,
 }
 
@@ -94,6 +93,7 @@ impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> {
             hir::CRATE_HIR_ID,
             self.cx.tcx.hir().root_module(),
             self.cx.tcx.crate_name(LOCAL_CRATE),
+            None,
         );
 
         // `#[macro_export] macro_rules!` items are reexported at the top level of the
@@ -114,7 +114,7 @@ impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> {
                     if self.cx.tcx.has_attr(def_id, sym::macro_export) {
                         if inserted.insert(def_id) {
                             let item = self.cx.tcx.hir().expect_item(local_def_id);
-                            top_level_module.items.push((item, None));
+                            top_level_module.items.push((item, None, None));
                         }
                     }
                 }
@@ -156,6 +156,7 @@ impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> {
         id: hir::HirId,
         m: &'tcx hir::Mod<'tcx>,
         name: Symbol,
+        parent_id: Option<hir::HirId>,
     ) -> Module<'tcx> {
         let mut om = Module::new(name, id, m.spans.inner_span);
         let def_id = self.cx.tcx.hir().local_def_id(id).to_def_id();
@@ -167,7 +168,7 @@ impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> {
             if matches!(item.kind, hir::ItemKind::Use(_, hir::UseKind::Glob)) {
                 continue;
             }
-            self.visit_item(item, None, &mut om);
+            self.visit_item(item, None, &mut om, parent_id);
         }
         for &i in m.item_ids {
             let item = self.cx.tcx.hir().item(i);
@@ -175,7 +176,7 @@ impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> {
             // Later passes in rustdoc will de-duplicate by name and kind, so if glob-
             // imported items appear last, then they'll be the ones that get discarded.
             if matches!(item.kind, hir::ItemKind::Use(_, hir::UseKind::Glob)) {
-                self.visit_item(item, None, &mut om);
+                self.visit_item(item, None, &mut om, parent_id);
             }
         }
         self.inside_public_path = orig_inside_public_path;
@@ -221,23 +222,7 @@ impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> {
         // made reachable by cross-crate inlining which we're checking here.
         // (this is done here because we need to know this upfront).
         if !res_did.is_local() && !is_no_inline {
-            let attrs = clean::inline::load_attrs(self.cx, res_did);
-            let self_is_hidden = attrs.lists(sym::doc).has_word(sym::hidden);
-            if !self_is_hidden {
-                if let Res::Def(kind, did) = res {
-                    if kind == DefKind::Mod {
-                        crate::visit_lib::LibEmbargoVisitor::new(self.cx).visit_mod(did)
-                    } else {
-                        // All items need to be handled here in case someone wishes to link
-                        // to them with intra-doc links
-                        self.cx.cache.access_levels.set_access_level(
-                            did,
-                            || Visibility::Restricted(CRATE_DEF_ID),
-                            AccessLevel::Public,
-                        );
-                    }
-                }
-            }
+            crate::visit_lib::lib_embargo_visit_item(self.cx, res_did);
             return false;
         }
 
@@ -246,7 +231,8 @@ impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> {
             None => return false,
         };
 
-        let is_private = !self.cx.cache.access_levels.is_public(res_did);
+        let is_private =
+            !self.cx.cache.effective_visibilities.is_directly_public(self.cx.tcx, res_did);
         let is_hidden = inherits_doc_hidden(self.cx.tcx, res_hir_id);
 
         // Only inline if requested or if the item would otherwise be stripped.
@@ -263,14 +249,14 @@ impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> {
                 let prev = mem::replace(&mut self.inlining, true);
                 for &i in m.item_ids {
                     let i = self.cx.tcx.hir().item(i);
-                    self.visit_item(i, None, om);
+                    self.visit_item(i, None, om, Some(id));
                 }
                 self.inlining = prev;
                 true
             }
             Node::Item(it) if !glob => {
                 let prev = mem::replace(&mut self.inlining, true);
-                self.visit_item(it, renamed, om);
+                self.visit_item(it, renamed, om, Some(id));
                 self.inlining = prev;
                 true
             }
@@ -291,15 +277,16 @@ impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> {
         item: &'tcx hir::Item<'_>,
         renamed: Option<Symbol>,
         om: &mut Module<'tcx>,
+        parent_id: Option<hir::HirId>,
     ) {
         debug!("visiting item {:?}", item);
         let name = renamed.unwrap_or(item.ident.name);
 
-        let def_id = item.def_id.to_def_id();
+        let def_id = item.owner_id.to_def_id();
         let is_pub = self.cx.tcx.visibility(def_id).is_public();
 
         if is_pub {
-            self.store_path(item.def_id.to_def_id());
+            self.store_path(item.owner_id.to_def_id());
         }
 
         match item.kind {
@@ -346,7 +333,7 @@ impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> {
                     }
                 }
 
-                om.items.push((item, renamed))
+                om.items.push((item, renamed, parent_id))
             }
             hir::ItemKind::Macro(ref macro_def, _) => {
                 // `#[macro_export] macro_rules!` items are handled separately in `visit()`,
@@ -360,16 +347,16 @@ impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> {
                 // 3. We're inlining, since a reexport where inlining has been requested
                 //    should be inlined even if it is also documented at the top level.
 
-                let def_id = item.def_id.to_def_id();
+                let def_id = item.owner_id.to_def_id();
                 let is_macro_2_0 = !macro_def.macro_rules;
                 let nonexported = !self.cx.tcx.has_attr(def_id, sym::macro_export);
 
                 if is_macro_2_0 || nonexported || self.inlining {
-                    om.items.push((item, renamed));
+                    om.items.push((item, renamed, None));
                 }
             }
             hir::ItemKind::Mod(ref m) => {
-                om.mods.push(self.visit_mod_contents(item.hir_id(), m, name));
+                om.mods.push(self.visit_mod_contents(item.hir_id(), m, name, parent_id));
             }
             hir::ItemKind::Fn(..)
             | hir::ItemKind::ExternCrate(..)
@@ -380,19 +367,19 @@ impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> {
             | hir::ItemKind::OpaqueTy(..)
             | hir::ItemKind::Static(..)
             | hir::ItemKind::Trait(..)
-            | hir::ItemKind::TraitAlias(..) => om.items.push((item, renamed)),
+            | hir::ItemKind::TraitAlias(..) => om.items.push((item, renamed, parent_id)),
             hir::ItemKind::Const(..) => {
                 // Underscore constants do not correspond to a nameable item and
                 // so are never useful in documentation.
                 if name != kw::Underscore {
-                    om.items.push((item, renamed));
+                    om.items.push((item, renamed, parent_id));
                 }
             }
             hir::ItemKind::Impl(impl_) => {
                 // Don't duplicate impls when inlining or if it's implementing a trait, we'll pick
                 // them up regardless of where they're located.
                 if !self.inlining && impl_.of_trait.is_none() {
-                    om.items.push((item, None));
+                    om.items.push((item, None, None));
                 }
             }
         }
@@ -405,7 +392,7 @@ impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> {
         om: &mut Module<'tcx>,
     ) {
         // If inlining we only want to include public functions.
-        if !self.inlining || self.cx.tcx.visibility(item.def_id).is_public() {
+        if !self.inlining || self.cx.tcx.visibility(item.owner_id).is_public() {
             om.foreigns.push((item, renamed));
         }
     }
diff --git a/src/librustdoc/visit_lib.rs b/src/librustdoc/visit_lib.rs
index 0511494668b1..e490559b0e92 100644
--- a/src/librustdoc/visit_lib.rs
+++ b/src/librustdoc/visit_lib.rs
@@ -1,86 +1,74 @@
+use crate::core::DocContext;
 use rustc_data_structures::fx::FxHashSet;
-use rustc_hir::def::{DefKind, Res};
-use rustc_hir::def_id::{CrateNum, DefId, CRATE_DEF_ID};
-use rustc_middle::middle::privacy::{AccessLevel, AccessLevels};
-use rustc_middle::ty::{TyCtxt, Visibility};
+use rustc_hir::def::DefKind;
+use rustc_hir::def_id::DefId;
+use rustc_middle::ty::TyCtxt;
 
 // FIXME: this may not be exhaustive, but is sufficient for rustdocs current uses
 
+#[derive(Default)]
+pub(crate) struct RustdocEffectiveVisibilities {
+    extern_public: FxHashSet<DefId>,
+}
+
+macro_rules! define_method {
+    ($method:ident) => {
+        pub(crate) fn $method(&self, tcx: TyCtxt<'_>, def_id: DefId) -> bool {
+            match def_id.as_local() {
+                Some(def_id) => tcx.effective_visibilities(()).$method(def_id),
+                None => self.extern_public.contains(&def_id),
+            }
+        }
+    };
+}
+
+impl RustdocEffectiveVisibilities {
+    define_method!(is_directly_public);
+    define_method!(is_exported);
+    define_method!(is_reachable);
+}
+
+pub(crate) fn lib_embargo_visit_item(cx: &mut DocContext<'_>, def_id: DefId) {
+    assert!(!def_id.is_local());
+    LibEmbargoVisitor {
+        tcx: cx.tcx,
+        extern_public: &mut cx.cache.effective_visibilities.extern_public,
+        visited_mods: Default::default(),
+    }
+    .visit_item(def_id)
+}
+
 /// Similar to `librustc_privacy::EmbargoVisitor`, but also takes
 /// specific rustdoc annotations into account (i.e., `doc(hidden)`)
-pub(crate) struct LibEmbargoVisitor<'a, 'tcx> {
+struct LibEmbargoVisitor<'a, 'tcx> {
     tcx: TyCtxt<'tcx>,
-    // Accessibility levels for reachable nodes
-    access_levels: &'a mut AccessLevels<DefId>,
-    // Previous accessibility level, None means unreachable
-    prev_level: Option<AccessLevel>,
+    // Effective visibilities for reachable nodes
+    extern_public: &'a mut FxHashSet<DefId>,
     // Keeps track of already visited modules, in case a module re-exports its parent
     visited_mods: FxHashSet<DefId>,
 }
 
-impl<'a, 'tcx> LibEmbargoVisitor<'a, 'tcx> {
-    pub(crate) fn new(cx: &'a mut crate::core::DocContext<'tcx>) -> LibEmbargoVisitor<'a, 'tcx> {
-        LibEmbargoVisitor {
-            tcx: cx.tcx,
-            access_levels: &mut cx.cache.access_levels,
-            prev_level: Some(AccessLevel::Public),
-            visited_mods: FxHashSet::default(),
-        }
-    }
-
-    pub(crate) fn visit_lib(&mut self, cnum: CrateNum) {
-        let did = cnum.as_def_id();
-        self.update(did, Some(AccessLevel::Public));
-        self.visit_mod(did);
-    }
-
-    // Updates node level and returns the updated level
-    fn update(&mut self, did: DefId, level: Option<AccessLevel>) -> Option<AccessLevel> {
-        let is_hidden = self.tcx.is_doc_hidden(did);
-
-        let old_level = self.access_levels.get_access_level(did);
-        // Accessibility levels can only grow
-        if level > old_level && !is_hidden {
-            self.access_levels.set_access_level(
-                did,
-                || Visibility::Restricted(CRATE_DEF_ID),
-                level.unwrap(),
-            );
-            level
-        } else {
-            old_level
-        }
-    }
-
-    pub(crate) fn visit_mod(&mut self, def_id: DefId) {
+impl LibEmbargoVisitor<'_, '_> {
+    fn visit_mod(&mut self, def_id: DefId) {
         if !self.visited_mods.insert(def_id) {
             return;
         }
 
         for item in self.tcx.module_children(def_id).iter() {
             if let Some(def_id) = item.res.opt_def_id() {
-                if self.tcx.def_key(def_id).parent.map_or(false, |d| d == def_id.index)
-                    || item.vis.is_public()
-                {
-                    self.visit_item(item.res);
+                if item.vis.is_public() {
+                    self.visit_item(def_id);
                 }
             }
         }
     }
 
-    fn visit_item(&mut self, res: Res<!>) {
-        let def_id = res.def_id();
-        let vis = self.tcx.visibility(def_id);
-        let inherited_item_level = if vis.is_public() { self.prev_level } else { None };
-
-        let item_level = self.update(def_id, inherited_item_level);
-
-        if let Res::Def(DefKind::Mod, _) = res {
-            let orig_level = self.prev_level;
-
-            self.prev_level = item_level;
-            self.visit_mod(def_id);
-            self.prev_level = orig_level;
+    fn visit_item(&mut self, def_id: DefId) {
+        if !self.tcx.is_doc_hidden(def_id) {
+            self.extern_public.insert(def_id);
+            if self.tcx.def_kind(def_id) == DefKind::Mod {
+                self.visit_mod(def_id);
+            }
         }
     }
 }
diff --git a/src/llvm-project b/src/llvm-project
index 4b8525577211..a1232c451fc2 160000
--- a/src/llvm-project
+++ b/src/llvm-project
@@ -1 +1 @@
-Subproject commit 4b85255772114ca4946d95fe591933dae7d61991
+Subproject commit a1232c451fc27173f8718e05d174b2503ca0b607
diff --git a/src/rustdoc-json-types/lib.rs b/src/rustdoc-json-types/lib.rs
index 7379b04ad167..817b3e484194 100644
--- a/src/rustdoc-json-types/lib.rs
+++ b/src/rustdoc-json-types/lib.rs
@@ -51,6 +51,11 @@ pub struct ItemSummary {
     pub crate_id: u32,
     /// The list of path components for the fully qualified path of this item (e.g.
     /// `["std", "io", "lazy", "Lazy"]` for `std::io::lazy::Lazy`).
+    ///
+    /// Note that items can appear in multiple paths, and the one chosen is implementation
+    /// defined. Currently, this is the full path to where the item was defined. Eg
+    /// [`String`] is currently `["alloc", "string", "String"]` and [`HashMap`] is
+    /// `["std", "collections", "hash", "map", "HashMap"]`, but this is subject to change.
     pub path: Vec<String>,
     /// Whether this item is a struct, trait, macro, etc.
     pub kind: ItemKind,
@@ -346,7 +351,7 @@ pub enum Variant {
     /// A variant with unnamed fields.
     ///
     /// Unlike most of json, `#[doc(hidden)]` fields will be given as `None`
-    /// instead of being ommited, because order matters.
+    /// instead of being omitted, because order matters.
     ///
     /// ```rust
     /// enum Demo {
diff --git a/src/stage0.json b/src/stage0.json
index 72308d50c8eb..c3f50272b67c 100644
--- a/src/stage0.json
+++ b/src/stage0.json
@@ -17,349 +17,349 @@
     "tool is executed."
   ],
   "compiler": {
-    "date": "2022-09-20",
+    "date": "2022-11-01",
     "version": "beta"
   },
   "rustfmt": {
-    "date": "2022-09-20",
+    "date": "2022-11-01",
     "version": "nightly"
   },
   "checksums_sha256": {
-    "dist/2022-09-20/cargo-beta-aarch64-apple-darwin.tar.gz": "3186f69cc7efaf3f933ad77798ddf58bf11c0719dc1dec53fadc502a236ef753",
-    "dist/2022-09-20/cargo-beta-aarch64-apple-darwin.tar.xz": "5ad195346a21a80c700ca08223060ea66298fe8e4cbac19148d14b92a9319b01",
-    "dist/2022-09-20/cargo-beta-aarch64-pc-windows-msvc.tar.gz": "6a7647d761ce3adba9d4ceff2e6c1929e9d96d767961a7a062f41ec09a1abb85",
-    "dist/2022-09-20/cargo-beta-aarch64-pc-windows-msvc.tar.xz": "13566a68dd2000fb33a990c21b62b82e77d1bd1f3384152f439cf96318f07f3e",
-    "dist/2022-09-20/cargo-beta-aarch64-unknown-linux-gnu.tar.gz": "cc698fe69e27a077c6d2aa8dc7319847b1ecd78ad4e3519161957c7cab90c592",
-    "dist/2022-09-20/cargo-beta-aarch64-unknown-linux-gnu.tar.xz": "1cd369b8ab90e85da78784cf08a92aee87f0804b448676637ee48cb3409dc026",
-    "dist/2022-09-20/cargo-beta-aarch64-unknown-linux-musl.tar.gz": "856170acebfd7900448fe02bd835d633b2930e2401c4211d72e5dd8c38943606",
-    "dist/2022-09-20/cargo-beta-aarch64-unknown-linux-musl.tar.xz": "5bbc32a426071c84d39395c64e1f9cfe0db29ab10c255c2a8a8f748b624cdb7a",
-    "dist/2022-09-20/cargo-beta-arm-unknown-linux-gnueabi.tar.gz": "50518c889d2408a7edf524c0340c8ff6881fd14f505dca0d419deefdb94c3afb",
-    "dist/2022-09-20/cargo-beta-arm-unknown-linux-gnueabi.tar.xz": "8143057e446c169e614c153ffbe2428e94404af96d06b1d3103028f695388211",
-    "dist/2022-09-20/cargo-beta-arm-unknown-linux-gnueabihf.tar.gz": "987064edfdb30dde07ef9b2cbd072f66ca042bf95ae724909cafbc13bcf69885",
-    "dist/2022-09-20/cargo-beta-arm-unknown-linux-gnueabihf.tar.xz": "253161f50a399818a77360f97443ef818dfca3d384e86048655b08c8a799bafc",
-    "dist/2022-09-20/cargo-beta-armv7-unknown-linux-gnueabihf.tar.gz": "7b9a0feee8f3e1e3c58df38f947904d76006c938a2395650e094337ede9918e9",
-    "dist/2022-09-20/cargo-beta-armv7-unknown-linux-gnueabihf.tar.xz": "2194b642b8ed595b8534ded204a72f910215c8f42482ac64644f784a3b2ae8b3",
-    "dist/2022-09-20/cargo-beta-i686-pc-windows-gnu.tar.gz": "7cc2c490988dd1ae095198664317cb0b5c8071fc31bf49aed1eca21eb2766cd8",
-    "dist/2022-09-20/cargo-beta-i686-pc-windows-gnu.tar.xz": "32641252e12cdadf0a232b43103fc56af621a48056864ff2ee9a034dd2da8f1f",
-    "dist/2022-09-20/cargo-beta-i686-pc-windows-msvc.tar.gz": "32581e6bf22e7d2c7a147a87158161e3fa07f46ec0252e632a3bafb824382a28",
-    "dist/2022-09-20/cargo-beta-i686-pc-windows-msvc.tar.xz": "a9a68905a4540389d28e40cc2137cf2fcca77c425089cd99072a34ba15e3ab6a",
-    "dist/2022-09-20/cargo-beta-i686-unknown-linux-gnu.tar.gz": "b5d9ecd7be4ab25919cd0731bb28a2612965943c5ccedf35ac09c169ed2c97db",
-    "dist/2022-09-20/cargo-beta-i686-unknown-linux-gnu.tar.xz": "387f7d95d04503293f708f65821f55878449eb5a0efe3344005dca18b84e6563",
-    "dist/2022-09-20/cargo-beta-mips-unknown-linux-gnu.tar.gz": "f8fbf21aac677276cdf246748d59d183e566bfcacabcd3eab6f19d6c857193ef",
-    "dist/2022-09-20/cargo-beta-mips-unknown-linux-gnu.tar.xz": "70e561d77632d1463839a8ea9cb72ff49afb61dbba95fa321bdba74be384b21f",
-    "dist/2022-09-20/cargo-beta-mips64-unknown-linux-gnuabi64.tar.gz": "e81b5a5fc70a1f7ed5920a3860b1259a2cecd9a1d981f2a564cd936de53ecf8a",
-    "dist/2022-09-20/cargo-beta-mips64-unknown-linux-gnuabi64.tar.xz": "ef9de44d1d37812bfeb67b353f1e308bf46d62c9fe191980de3a62fbfe5167a4",
-    "dist/2022-09-20/cargo-beta-mips64el-unknown-linux-gnuabi64.tar.gz": "68c1cd309775626f19431f7dbb73789b17ee629b588e05bf0231313913cb6a8a",
-    "dist/2022-09-20/cargo-beta-mips64el-unknown-linux-gnuabi64.tar.xz": "db290a98987c8bd527f1efe9ff09055fdce8eea0673d2c5eba0640649396b8d0",
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 }
diff --git a/src/test/assembly/strict_provenance.rs b/src/test/assembly/strict_provenance.rs
new file mode 100644
index 000000000000..01f1957d5f66
--- /dev/null
+++ b/src/test/assembly/strict_provenance.rs
@@ -0,0 +1,37 @@
+// assembly-output: emit-asm
+// compile-flags: -Copt-level=1
+// only-x86_64
+// min-llvm-version: 15.0
+#![crate_type = "rlib"]
+
+// CHECK-LABEL: old_style
+// CHECK: movq %{{.*}}, %rax
+// CHECK: orq $1, %rax
+// CHECK: retq
+#[no_mangle]
+pub fn old_style(a: *mut u8) -> *mut u8 {
+    (a as usize | 1) as *mut u8
+}
+
+// CHECK-LABEL: cheri_compat
+// CHECK: movq %{{.*}}, %rax
+// CHECK: orq $1, %rax
+// CHECK: retq
+#[no_mangle]
+pub fn cheri_compat(a: *mut u8) -> *mut u8 {
+    let old = a as usize;
+    let new = old | 1;
+    let diff = new.wrapping_sub(old);
+    a.wrapping_add(diff)
+}
+
+// CHECK-LABEL: definitely_not_a_null_pointer
+// CHECK: movq %{{.*}}, %rax
+// CHECK: orq $1, %rax
+// CHECK: retq
+#[no_mangle]
+pub fn definitely_not_a_null_pointer(a: *mut u8) -> *mut u8 {
+    let old = a as usize;
+    let new = old | 1;
+    a.wrapping_sub(old).wrapping_add(new)
+}
diff --git a/src/test/codegen/abi-efiapi.rs b/src/test/codegen/abi-efiapi.rs
index b4fda5f8c842..9061d7432a3f 100644
--- a/src/test/codegen/abi-efiapi.rs
+++ b/src/test/codegen/abi-efiapi.rs
@@ -27,7 +27,7 @@ trait Copy { }
 //x86_64: define win64cc void @has_efiapi
 //i686: define void @has_efiapi
 //aarch64: define dso_local void @has_efiapi
-//arm: define dso_local void @has_efiapi
+//arm: define dso_local arm_aapcscc void @has_efiapi
 //riscv: define dso_local void @has_efiapi
 #[no_mangle]
 pub extern "efiapi" fn has_efiapi() {}
diff --git a/src/test/codegen/auxiliary/static_dllimport_aux.rs b/src/test/codegen/auxiliary/static_dllimport_aux.rs
new file mode 100644
index 000000000000..afb0dc42f443
--- /dev/null
+++ b/src/test/codegen/auxiliary/static_dllimport_aux.rs
@@ -0,0 +1,13 @@
+use std::sync::atomic::{AtomicPtr, Ordering};
+
+#[inline(always)]
+pub fn memrchr() {
+    fn detect() {}
+
+    static CROSS_CRATE_STATIC_ITEM: AtomicPtr<()> = AtomicPtr::new(detect as *mut ());
+
+    unsafe {
+        let fun = CROSS_CRATE_STATIC_ITEM.load(Ordering::SeqCst);
+        std::mem::transmute::<*mut (), fn()>(fun)()
+    }
+}
diff --git a/src/test/codegen/avr/avr-func-addrspace.rs b/src/test/codegen/avr/avr-func-addrspace.rs
index a038dfe76f70..cbbcfad3ef48 100644
--- a/src/test/codegen/avr/avr-func-addrspace.rs
+++ b/src/test/codegen/avr/avr-func-addrspace.rs
@@ -19,6 +19,8 @@ pub trait Sized { }
 pub trait Copy { }
 #[lang = "receiver"]
 pub trait Receiver { }
+#[lang = "tuple_trait"]
+pub trait Tuple { }
 
 pub struct Result<T, E> { _a: T, _b: E }
 
@@ -29,7 +31,7 @@ impl Copy for &usize {}
 pub unsafe fn drop_in_place<T: ?Sized>(_: *mut T) {}
 
 #[lang = "fn_once"]
-pub trait FnOnce<Args> {
+pub trait FnOnce<Args: Tuple> {
     #[lang = "fn_once_output"]
     type Output;
 
@@ -37,24 +39,16 @@ pub trait FnOnce<Args> {
 }
 
 #[lang = "fn_mut"]
-pub trait FnMut<Args> : FnOnce<Args> {
+pub trait FnMut<Args: Tuple> : FnOnce<Args> {
     extern "rust-call" fn call_mut(&mut self, args: Args) -> Self::Output;
 }
 
 #[lang = "fn"]
-pub trait Fn<Args>: FnOnce<Args> {
+pub trait Fn<Args: Tuple>: FnOnce<Args> {
     /// Performs the call operation.
     extern "rust-call" fn call(&self, args: Args) -> Self::Output;
 }
 
-impl<'a, A, R> FnOnce<A> for &'a fn(A) -> R {
-    type Output = R;
-
-    extern "rust-call" fn call_once(self, args: A) -> R {
-        (*self)(args)
-    }
-}
-
 pub static mut STORAGE_FOO: fn(&usize, &mut u32) -> Result<(), ()> = arbitrary_black_box;
 pub static mut STORAGE_BAR: u32 = 12;
 
diff --git a/src/test/codegen/enum-bounds-check-derived-idx.rs b/src/test/codegen/enum-bounds-check-derived-idx.rs
index fe02aeb5f625..aa66c2ed08ed 100644
--- a/src/test/codegen/enum-bounds-check-derived-idx.rs
+++ b/src/test/codegen/enum-bounds-check-derived-idx.rs
@@ -12,15 +12,13 @@ pub enum Bar {
 // CHECK-LABEL: @lookup_inc
 #[no_mangle]
 pub fn lookup_inc(buf: &[u8; 5], f: Bar) -> u8 {
-    // FIXME: panic check can be removed by adding the assumes back after https://github.com/rust-lang/rust/pull/98332
-    // CHECK: panic_bounds_check
+    // CHECK-NOT: panic_bounds_check
     buf[f as usize + 1]
 }
 
 // CHECK-LABEL: @lookup_dec
 #[no_mangle]
 pub fn lookup_dec(buf: &[u8; 5], f: Bar) -> u8 {
-    // FIXME: panic check can be removed by adding the assumes back after https://github.com/rust-lang/rust/pull/98332
-    // CHECK: panic_bounds_check
+    // CHECK-NOT: panic_bounds_check
     buf[f as usize - 1]
 }
diff --git a/src/test/codegen/enum-bounds-check-issue-13926.rs b/src/test/codegen/enum-bounds-check-issue-13926.rs
index 1aec41d54411..b26945bc5494 100644
--- a/src/test/codegen/enum-bounds-check-issue-13926.rs
+++ b/src/test/codegen/enum-bounds-check-issue-13926.rs
@@ -13,7 +13,6 @@ pub enum Exception {
 // CHECK-LABEL: @access
 #[no_mangle]
 pub fn access(array: &[usize; 12], exc: Exception) -> usize {
-    // FIXME: panic check can be removed by adding the assumes back after https://github.com/rust-lang/rust/pull/98332
-    // CHECK: panic_bounds_check
+    // CHECK-NOT: panic_bounds_check
     array[(exc as u8 - 4) as usize]
 }
diff --git a/src/test/codegen/enum-bounds-check.rs b/src/test/codegen/enum-bounds-check.rs
index f85c6817deda..17322d5911b9 100644
--- a/src/test/codegen/enum-bounds-check.rs
+++ b/src/test/codegen/enum-bounds-check.rs
@@ -21,7 +21,6 @@ pub enum Bar {
 // CHECK-LABEL: @lookup_unmodified
 #[no_mangle]
 pub fn lookup_unmodified(buf: &[u8; 5], f: Bar) -> u8 {
-    // FIXME: panic check can be removed by adding the assumes back after https://github.com/rust-lang/rust/pull/98332
-    // CHECK: panic_bounds_check
+    // CHECK-NOT: panic_bounds_check
     buf[f as usize]
 }
diff --git a/src/test/codegen/enum-match.rs b/src/test/codegen/enum-match.rs
new file mode 100644
index 000000000000..efab189fd7b8
--- /dev/null
+++ b/src/test/codegen/enum-match.rs
@@ -0,0 +1,112 @@
+// compile-flags: -Copt-level=1
+// only-x86_64
+
+#![crate_type = "lib"]
+
+// Check each of the 3 cases for `codegen_get_discr`.
+
+// Case 0: One tagged variant.
+pub enum Enum0 {
+    A(bool),
+    B,
+}
+
+// CHECK: define i8 @match0{{.*}}
+// CHECK-NEXT: start:
+// CHECK-NEXT: %1 = icmp eq i8 %0, 2
+// CHECK-NEXT: %2 = and i8 %0, 1
+// CHECK-NEXT: %.0 = select i1 %1, i8 13, i8 %2
+#[no_mangle]
+pub fn match0(e: Enum0) -> u8 {
+    use Enum0::*;
+    match e {
+        A(b) => b as u8,
+        B => 13,
+    }
+}
+
+// Case 1: Niche values are on a boundary for `range`.
+pub enum Enum1 {
+    A(bool),
+    B,
+    C,
+}
+
+// CHECK: define i8 @match1{{.*}}
+// CHECK-NEXT: start:
+// CHECK-NEXT: %1 = icmp ugt i8 %0, 1
+// CHECK-NEXT: %2 = zext i8 %0 to i64
+// CHECK-NEXT: %3 = add nsw i64 %2, -1
+// CHECK-NEXT: %_2 = select i1 %1, i64 %3, i64 0
+// CHECK-NEXT: switch i64 %_2, label {{.*}} [
+#[no_mangle]
+pub fn match1(e: Enum1) -> u8 {
+    use Enum1::*;
+    match e {
+        A(b) => b as u8,
+        B => 13,
+        C => 100,
+    }
+}
+
+// Case 2: Special cases don't apply.
+pub enum X {
+    _2=2, _3, _4, _5, _6, _7, _8, _9, _10, _11,
+    _12, _13, _14, _15, _16, _17, _18, _19, _20,
+    _21, _22, _23, _24, _25, _26, _27, _28, _29,
+    _30, _31, _32, _33, _34, _35, _36, _37, _38,
+    _39, _40, _41, _42, _43, _44, _45, _46, _47,
+    _48, _49, _50, _51, _52, _53, _54, _55, _56,
+    _57, _58, _59, _60, _61, _62, _63, _64, _65,
+    _66, _67, _68, _69, _70, _71, _72, _73, _74,
+    _75, _76, _77, _78, _79, _80, _81, _82, _83,
+    _84, _85, _86, _87, _88, _89, _90, _91, _92,
+    _93, _94, _95, _96, _97, _98, _99, _100, _101,
+    _102, _103, _104, _105, _106, _107, _108, _109,
+    _110, _111, _112, _113, _114, _115, _116, _117,
+    _118, _119, _120, _121, _122, _123, _124, _125,
+    _126, _127, _128, _129, _130, _131, _132, _133,
+    _134, _135, _136, _137, _138, _139, _140, _141,
+    _142, _143, _144, _145, _146, _147, _148, _149,
+    _150, _151, _152, _153, _154, _155, _156, _157,
+    _158, _159, _160, _161, _162, _163, _164, _165,
+    _166, _167, _168, _169, _170, _171, _172, _173,
+    _174, _175, _176, _177, _178, _179, _180, _181,
+    _182, _183, _184, _185, _186, _187, _188, _189,
+    _190, _191, _192, _193, _194, _195, _196, _197,
+    _198, _199, _200, _201, _202, _203, _204, _205,
+    _206, _207, _208, _209, _210, _211, _212, _213,
+    _214, _215, _216, _217, _218, _219, _220, _221,
+    _222, _223, _224, _225, _226, _227, _228, _229,
+    _230, _231, _232, _233, _234, _235, _236, _237,
+    _238, _239, _240, _241, _242, _243, _244, _245,
+    _246, _247, _248, _249, _250, _251, _252, _253,
+}
+
+pub enum Enum2 {
+    A(X),
+    B,
+    C,
+    D,
+    E,
+}
+
+// CHECK: define i8 @match2{{.*}}
+// CHECK-NEXT: start:
+// CHECK-NEXT: %1 = add i8 %0, 2
+// CHECK-NEXT: %2 = zext i8 %1 to i64
+// CHECK-NEXT: %3 = icmp ult i8 %1, 4
+// CHECK-NEXT: %4 = add nuw nsw i64 %2, 1
+// CHECK-NEXT: %_2 = select i1 %3, i64 %4, i64 0
+// CHECK-NEXT: switch i64 %_2, label {{.*}} [
+#[no_mangle]
+pub fn match2(e: Enum2) -> u8 {
+    use Enum2::*;
+    match e {
+        A(b) => b as u8,
+        B => 13,
+        C => 100,
+        D => 200,
+        E => 250,
+    }
+}
diff --git a/src/test/codegen/ffi-const.rs b/src/test/codegen/ffi-const.rs
index d9cfa5429b5b..937205034808 100644
--- a/src/test/codegen/ffi-const.rs
+++ b/src/test/codegen/ffi-const.rs
@@ -7,6 +7,7 @@ pub fn bar() { unsafe { foo() } }
 extern "C" {
     // CHECK-LABEL: declare{{.*}}void @foo()
     // CHECK-SAME: [[ATTRS:#[0-9]+]]
-    // CHECK-DAG: attributes [[ATTRS]] = { {{.*}}readnone{{.*}} }
+    // The attribute changed from `readnone` to `memory(none)` with LLVM 16.0.
+    // CHECK-DAG: attributes [[ATTRS]] = { {{.*}}{{readnone|memory\(none\)}}{{.*}} }
     #[ffi_const] pub fn foo();
 }
diff --git a/src/test/codegen/ffi-pure.rs b/src/test/codegen/ffi-pure.rs
index 5bdb2ee912a1..2ed735813582 100644
--- a/src/test/codegen/ffi-pure.rs
+++ b/src/test/codegen/ffi-pure.rs
@@ -7,6 +7,7 @@ pub fn bar() { unsafe { foo() } }
 extern "C" {
     // CHECK-LABEL: declare{{.*}}void @foo()
     // CHECK-SAME: [[ATTRS:#[0-9]+]]
-    // CHECK-DAG: attributes [[ATTRS]] = { {{.*}}readonly{{.*}} }
+    // The attribute changed from `readonly` to `memory(read)` with LLVM 16.0.
+    // CHECK-DAG: attributes [[ATTRS]] = { {{.*}}{{readonly|memory\(read\)}}{{.*}} }
     #[ffi_pure] pub fn foo();
 }
diff --git a/src/test/codegen/issue-103285-ptr-addr-overflow-check.rs b/src/test/codegen/issue-103285-ptr-addr-overflow-check.rs
new file mode 100644
index 000000000000..a3499babea21
--- /dev/null
+++ b/src/test/codegen/issue-103285-ptr-addr-overflow-check.rs
@@ -0,0 +1,16 @@
+// compile-flags: -O -C debug-assertions=yes
+
+#![crate_type = "lib"]
+#![feature(strict_provenance)]
+
+#[no_mangle]
+pub fn test(src: *const u8, dst: *const u8) -> usize {
+    // CHECK-LABEL: @test(
+    // CHECK-NOT: panic
+    let src_usize = src.addr();
+    let dst_usize = dst.addr();
+    if src_usize > dst_usize {
+        return src_usize - dst_usize;
+    }
+    return 0;
+}
diff --git a/src/test/codegen/issue-81408-dllimport-thinlto-windows.rs b/src/test/codegen/issue-81408-dllimport-thinlto-windows.rs
new file mode 100644
index 000000000000..0b6ab4f7ecb3
--- /dev/null
+++ b/src/test/codegen/issue-81408-dllimport-thinlto-windows.rs
@@ -0,0 +1,15 @@
+// compile-flags: -O -C lto=thin -C prefer-dynamic=no
+// only-windows
+// aux-build:static_dllimport_aux.rs
+
+// Test that on Windows, when performing ThinLTO, we do not mark cross-crate static items with
+// dllimport because lld does not fix the symbol names for us.
+
+extern crate static_dllimport_aux;
+
+// CHECK-LABEL: @{{.+}}CROSS_CRATE_STATIC_ITEM{{.+}} =
+// CHECK-SAME: external local_unnamed_addr global %"{{.+}}AtomicPtr
+
+pub fn main() {
+    static_dllimport_aux::memrchr();
+}
diff --git a/src/test/codegen/match-optimized.rs b/src/test/codegen/match-optimized.rs
new file mode 100644
index 000000000000..36402cc7353f
--- /dev/null
+++ b/src/test/codegen/match-optimized.rs
@@ -0,0 +1,60 @@
+// compile-flags: -C no-prepopulate-passes -O
+
+#![crate_type = "lib"]
+
+pub enum E {
+    A,
+    B,
+    C,
+}
+
+// CHECK-LABEL: @exhaustive_match
+#[no_mangle]
+pub fn exhaustive_match(e: E) -> u8 {
+// CHECK: switch{{.*}}, label %[[OTHERWISE:[a-zA-Z0-9_]+]] [
+// CHECK-NEXT: i[[TY:[0-9]+]] [[DISCR:[0-9]+]], label %[[A:[a-zA-Z0-9_]+]]
+// CHECK-NEXT: i[[TY:[0-9]+]] [[DISCR:[0-9]+]], label %[[B:[a-zA-Z0-9_]+]]
+// CHECK-NEXT: i[[TY:[0-9]+]] [[DISCR:[0-9]+]], label %[[C:[a-zA-Z0-9_]+]]
+// CHECK-NEXT: ]
+// CHECK: [[OTHERWISE]]:
+// CHECK-NEXT: unreachable
+//
+// CHECK: [[A]]:
+// CHECK-NEXT: store i8 0, {{i8\*|ptr}} %1, align 1
+// CHECK-NEXT: br label %[[EXIT:[a-zA-Z0-9_]+]]
+// CHECK: [[B]]:
+// CHECK-NEXT: store i8 1, {{i8\*|ptr}} %1, align 1
+// CHECK-NEXT: br label %[[EXIT]]
+// CHECK: [[C]]:
+// CHECK-NEXT: store i8 2, {{i8\*|ptr}} %1, align 1
+// CHECK-NEXT: br label %[[EXIT]]
+    match e {
+        E::A => 0,
+        E::B => 1,
+        E::C => 2,
+    }
+}
+
+#[repr(u16)]
+pub enum E2 {
+    A = 13,
+    B = 42,
+}
+
+// For optimized code we produce a switch with an unreachable target as the `otherwise` so LLVM
+// knows the possible values. Compare with `src/test/codegen/match-unoptimized.rs`.
+
+// CHECK-LABEL: @exhaustive_match_2
+#[no_mangle]
+pub fn exhaustive_match_2(e: E2) -> u8 {
+    // CHECK: switch i16 %{{.+}}, label %[[UNREACH:.+]] [
+    // CHECK-NEXT: i16 13,
+    // CHECK-NEXT: i16 42,
+    // CHECK-NEXT: ]
+    // CHECK: [[UNREACH]]:
+    // CHECK-NEXT: unreachable
+    match e {
+        E2::A => 0,
+        E2::B => 1,
+    }
+}
diff --git a/src/test/codegen/match-unoptimized.rs b/src/test/codegen/match-unoptimized.rs
new file mode 100644
index 000000000000..be40b29e3d3e
--- /dev/null
+++ b/src/test/codegen/match-unoptimized.rs
@@ -0,0 +1,23 @@
+// compile-flags: -C no-prepopulate-passes -Copt-level=0
+
+#![crate_type = "lib"]
+
+#[repr(u16)]
+pub enum E2 {
+    A = 13,
+    B = 42,
+}
+
+// For unoptimized code we produce a `br` instead of a `switch`. Compare with
+// `src/test/codegen/match-optimized.rs`
+
+// CHECK-LABEL: @exhaustive_match_2
+#[no_mangle]
+pub fn exhaustive_match_2(e: E2) -> u8 {
+    // CHECK: %[[CMP:.+]] = icmp eq i16 %{{.+}}, 13
+    // CHECK-NEXT: br i1 %[[CMP:.+]],
+    match e {
+        E2::A => 0,
+        E2::B => 1,
+    }
+}
diff --git a/src/test/codegen/match.rs b/src/test/codegen/match.rs
deleted file mode 100644
index b203641fddbd..000000000000
--- a/src/test/codegen/match.rs
+++ /dev/null
@@ -1,29 +0,0 @@
-// compile-flags: -C no-prepopulate-passes
-
-#![crate_type = "lib"]
-
-pub enum E {
-    A,
-    B,
-}
-
-// CHECK-LABEL: @exhaustive_match
-#[no_mangle]
-pub fn exhaustive_match(e: E) -> u8 {
-// CHECK: switch{{.*}}, label %[[OTHERWISE:[a-zA-Z0-9_]+]] [
-// CHECK-NEXT: i[[TY:[0-9]+]] [[DISCR:[0-9]+]], label %[[A:[a-zA-Z0-9_]+]]
-// CHECK-NEXT: i[[TY:[0-9]+]] [[DISCR:[0-9]+]], label %[[B:[a-zA-Z0-9_]+]]
-// CHECK-NEXT: ]
-// CHECK: [[OTHERWISE]]:
-// CHECK-NEXT: unreachable
-// CHECK: [[A]]:
-// CHECK-NEXT: store i8 0, {{i8\*|ptr}} %1, align 1
-// CHECK-NEXT: br label %[[EXIT:[a-zA-Z0-9_]+]]
-// CHECK: [[B]]:
-// CHECK-NEXT: store i8 1, {{i8\*|ptr}} %1, align 1
-// CHECK-NEXT: br label %[[EXIT:[a-zA-Z0-9_]+]]
-    match e {
-        E::A => 0,
-        E::B => 1,
-    }
-}
diff --git a/src/test/codegen/mir-inlined-line-numbers.rs b/src/test/codegen/mir-inlined-line-numbers.rs
new file mode 100644
index 000000000000..19d83f0eee7c
--- /dev/null
+++ b/src/test/codegen/mir-inlined-line-numbers.rs
@@ -0,0 +1,25 @@
+// compile-flags: -O -g
+
+#![crate_type = "lib"]
+
+#[inline(always)]
+fn foo() {
+    bar();
+}
+
+#[inline(never)]
+#[no_mangle]
+fn bar() {
+    panic!();
+}
+
+#[no_mangle]
+pub fn example() {
+    foo();
+}
+
+// CHECK-LABEL: @example
+// CHECK:   tail call void @bar(), !dbg [[DBG_ID:![0-9]+]]
+// CHECK: [[DBG_ID]] = !DILocation(line: 7,
+// CHECK-SAME:                     inlinedAt: [[INLINE_ID:![0-9]+]])
+// CHECK: [[INLINE_ID]] = !DILocation(line: 18,
diff --git a/src/test/debuginfo/basic-types.rs b/src/test/debuginfo/basic-types.rs
index 07d33be2a071..9e82f0714690 100644
--- a/src/test/debuginfo/basic-types.rs
+++ b/src/test/debuginfo/basic-types.rs
@@ -47,7 +47,6 @@
 // gdbg-check:$15 = {data_ptr = [...] "Hello, World!", length = 13}
 // gdbr-check:$15 = "Hello, World!"
 
-
 // === LLDB TESTS ==================================================================================
 
 // lldb-command:run
@@ -96,7 +95,6 @@
 // lldbg-check:[...]$12 = 3.5
 // lldbr-check:(f64) f64 = 3.5
 
-
 // === CDB TESTS ===================================================================================
 
 // cdb-command:g
@@ -131,7 +129,7 @@
 // cdb-command:.enable_unicode 1
 // FIXME(#88840): The latest version of the Windows SDK broke the visualizer for str.
 // cdb-command:dx  s
-// cdb-check:s                : [...] [Type: str]
+// cdb-check:s                : [...] [Type: ref$<str$>]
 
 #![allow(unused_variables)]
 #![feature(omit_gdb_pretty_printer_section)]
@@ -156,4 +154,6 @@ fn main() {
     _zzz(); // #break
 }
 
-fn _zzz() {()}
+fn _zzz() {
+    ()
+}
diff --git a/src/test/debuginfo/msvc-pretty-enums.rs b/src/test/debuginfo/msvc-pretty-enums.rs
index 7f1be6f27847..d66e4c660f7b 100644
--- a/src/test/debuginfo/msvc-pretty-enums.rs
+++ b/src/test/debuginfo/msvc-pretty-enums.rs
@@ -116,13 +116,13 @@
 // cdb-check: niche_w_fields_3_niche5,d : F [Type: enum2$<msvc_pretty_enums::NicheLayoutWithFields3>]
 
 // cdb-command: dx -r3 niche_w_fields_std_result_ok,d
-// cdb-check: niche_w_fields_std_result_ok,d : Ok [Type: enum2$<core::result::Result<alloc::boxed::Box<slice$<u8>,alloc::alloc::Global>,u64> >]
-// cdb-check:    [+0x[...]] __0              [Type: alloc::boxed::Box<slice$<u8>,alloc::alloc::Global>]
+// cdb-check: niche_w_fields_std_result_ok,d : Ok [Type: enum2$<core::result::Result<alloc::boxed::Box<slice2$<u8>,alloc::alloc::Global>,u64> >]
+// cdb-check:    [+0x[...]] __0              [Type: alloc::boxed::Box<slice2$<u8>,alloc::alloc::Global>]
 // cdb-check:        [+0x[...]] data_ptr         : [...]
 // cdb-check:        [+0x[...]] length           : 3 [...]
 
 // cdb-command: dx -r3 niche_w_fields_std_result_err,d
-// cdb-check: niche_w_fields_std_result_err,d : Err [Type: enum2$<core::result::Result<alloc::boxed::Box<slice$<u8>,alloc::alloc::Global>,u64> >]
+// cdb-check: niche_w_fields_std_result_err,d : Err [Type: enum2$<core::result::Result<alloc::boxed::Box<slice2$<u8>,alloc::alloc::Global>,u64> >]
 // cdb-check:    [+0x[...]] __0              : 789 [Type: unsigned __int64]
 
 // cdb-command: dx -r2 arbitrary_discr1,d
diff --git a/src/test/debuginfo/msvc-scalarpair-params.rs b/src/test/debuginfo/msvc-scalarpair-params.rs
index 9630952cbaae..ae67f6981519 100644
--- a/src/test/debuginfo/msvc-scalarpair-params.rs
+++ b/src/test/debuginfo/msvc-scalarpair-params.rs
@@ -38,14 +38,14 @@
 // cdb-command: g
 
 // cdb-command: dx s
-// cdb-check:s                : "this is a static str" [Type: str]
+// cdb-check:s                : "this is a static str" [Type: ref$<str$>]
 // cdb-check:    [len]            : 0x14 [Type: unsigned [...]]
 // cdb-check:    [chars]
 
 // cdb-command: g
 
 // cdb-command: dx s
-// cdb-check:s                : { len=0x5 } [Type: slice$<u8>]
+// cdb-check:s                : { len=0x5 } [Type: ref$<slice2$<u8> >]
 // cdb-check:    [len]            : 0x5 [Type: unsigned [...]]
 // cdb-check:    [0]              : 0x1 [Type: unsigned char]
 // cdb-check:    [1]              : 0x2 [Type: unsigned char]
diff --git a/src/test/debuginfo/mutex.rs b/src/test/debuginfo/mutex.rs
index 314ba40b0e3d..61ec6a81243d 100644
--- a/src/test/debuginfo/mutex.rs
+++ b/src/test/debuginfo/mutex.rs
@@ -10,7 +10,7 @@
 //
 // cdb-command:dx m,d
 // cdb-check:m,d              [Type: std::sync::mutex::Mutex<i32>]
-// cdb-check:    [...] inner            [Type: std::sys_common::mutex::MovableMutex]
+// cdb-check:    [...] inner            [Type: std::sys::windows::locks::mutex::Mutex]
 // cdb-check:    [...] poison           [Type: std::sync::poison::Flag]
 // cdb-check:    [...] data             : 0 [Type: core::cell::UnsafeCell<i32>]
 
diff --git a/src/test/debuginfo/pretty-std.rs b/src/test/debuginfo/pretty-std.rs
index a51b37205e8a..d8c6344e0b6a 100644
--- a/src/test/debuginfo/pretty-std.rs
+++ b/src/test/debuginfo/pretty-std.rs
@@ -69,7 +69,7 @@
 // cdb-command: g
 
 // cdb-command: dx slice,d
-// cdb-check:slice,d          : { len=4 } [Type: slice$<i32>]
+// cdb-check:slice,d          : { len=4 } [Type: ref$<slice2$<i32> >]
 // cdb-check:    [len]            : 4 [Type: [...]]
 // cdb-check:    [0]              : 0 [Type: int]
 // cdb-check:    [1]              : 1 [Type: int]
@@ -86,7 +86,7 @@
 // cdb-check:    [3]              : 7 [Type: unsigned __int64]
 
 // cdb-command: dx str_slice
-// cdb-check:str_slice        : "IAMA string slice!" [Type: str]
+// cdb-check:str_slice        : "IAMA string slice!" [Type: ref$<str$>]
 
 // cdb-command: dx string
 // cdb-check:string           : "IAMA string!" [Type: [...]::String]
diff --git a/src/test/debuginfo/rc_arc.rs b/src/test/debuginfo/rc_arc.rs
index c05c565d9563..5d5492d72177 100644
--- a/src/test/debuginfo/rc_arc.rs
+++ b/src/test/debuginfo/rc_arc.rs
@@ -57,7 +57,7 @@
 // cdb-check:    [Weak reference count] : 2 [Type: core::cell::Cell<usize>]
 
 // cdb-command:dx slice_rc,d
-// cdb-check:slice_rc,d       : { len=3 } [Type: alloc::rc::Rc<slice$<u32> >]
+// cdb-check:slice_rc,d       : { len=3 } [Type: alloc::rc::Rc<slice2$<u32> >]
 // cdb-check:    [Length]         : 3 [Type: [...]]
 // cdb-check:    [Reference count] : 41 [Type: core::cell::Cell<usize>]
 // cdb-check:    [Weak reference count] : 2 [Type: core::cell::Cell<usize>]
@@ -66,7 +66,7 @@
 // cdb-check:    [2]              : 3 [Type: u32]
 
 // cdb-command:dx slice_rc_weak,d
-// cdb-check:slice_rc_weak,d  : { len=3 } [Type: alloc::rc::Weak<slice$<u32> >]
+// cdb-check:slice_rc_weak,d  : { len=3 } [Type: alloc::rc::Weak<slice2$<u32> >]
 // cdb-check:    [Length]         : 3 [Type: [...]]
 // cdb-check:    [Reference count] : 41 [Type: core::cell::Cell<usize>]
 // cdb-check:    [Weak reference count] : 2 [Type: core::cell::Cell<usize>]
@@ -85,7 +85,7 @@
 // cdb-check:    [Weak reference count] : 2 [Type: core::sync::atomic::AtomicUsize]
 
 // cdb-command:dx slice_arc,d
-// cdb-check:slice_arc,d      : { len=3 } [Type: alloc::sync::Arc<slice$<u32> >]
+// cdb-check:slice_arc,d      : { len=3 } [Type: alloc::sync::Arc<slice2$<u32> >]
 // cdb-check:    [Length]         : 3 [Type: [...]]
 // cdb-check:    [Reference count] : 61 [Type: core::sync::atomic::AtomicUsize]
 // cdb-check:    [Weak reference count] : 2 [Type: core::sync::atomic::AtomicUsize]
@@ -94,7 +94,7 @@
 // cdb-check:    [2]              : 6 [Type: u32]
 
 // cdb-command:dx slice_arc_weak,d
-// cdb-check:slice_arc_weak,d : { len=3 } [Type: alloc::sync::Weak<slice$<u32> >]
+// cdb-check:slice_arc_weak,d : { len=3 } [Type: alloc::sync::Weak<slice2$<u32> >]
 // cdb-check:    [Length]         : 3 [Type: [...]]
 // cdb-check:    [Reference count] : 61 [Type: core::sync::atomic::AtomicUsize]
 // cdb-check:    [Weak reference count] : 2 [Type: core::sync::atomic::AtomicUsize]
diff --git a/src/test/debuginfo/result-types.rs b/src/test/debuginfo/result-types.rs
index cdac47a784d9..f1944fa38d27 100644
--- a/src/test/debuginfo/result-types.rs
+++ b/src/test/debuginfo/result-types.rs
@@ -7,12 +7,12 @@
 // cdb-command: g
 
 // cdb-command: dx x,d
-// cdb-check:x,d              : Ok [Type: enum2$<core::result::Result<i32,str> >]
+// cdb-check:x,d              : Ok [Type: enum2$<core::result::Result<i32,ref$<str$> > >]
 // cdb-check:    [...] __0              : -3 [Type: int]
 
 // cdb-command: dx y
-// cdb-check:y                : Err [Type: enum2$<core::result::Result<i32,str> >]
-// cdb-check:    [...] __0              : "Some error message" [Type: str]
+// cdb-check:y                : Err [Type: enum2$<core::result::Result<i32,ref$<str$> > >]
+// cdb-check:    [...] __0              : "Some error message" [Type: ref$<str$>]
 
 fn main() {
     let x: Result<i32, &str> = Ok(-3);
diff --git a/src/test/debuginfo/rwlock-read.rs b/src/test/debuginfo/rwlock-read.rs
index ed9aae16b0db..bc42f92f053d 100644
--- a/src/test/debuginfo/rwlock-read.rs
+++ b/src/test/debuginfo/rwlock-read.rs
@@ -16,7 +16,7 @@
 // cdb-command:dx r
 // cdb-check:r                [Type: std::sync::rwlock::RwLockReadGuard<i32>]
 // cdb-check:    [...] data             : NonNull([...]: 0) [Type: core::ptr::non_null::NonNull<i32>]
-// cdb-check:    [...] inner_lock       : [...] [Type: std::sys_common::rwlock::MovableRwLock *]
+// cdb-check:    [...] inner_lock       : [...] [Type: std::sys::windows::locks::rwlock::RwLock *]
 
 #[allow(unused_variables)]
 
diff --git a/src/test/debuginfo/type-names.rs b/src/test/debuginfo/type-names.rs
index 9cc99d7767c1..d7b79a845d25 100644
--- a/src/test/debuginfo/type-names.rs
+++ b/src/test/debuginfo/type-names.rs
@@ -95,7 +95,7 @@
 // gdb-check:type = &[usize]
 
 // gdb-command:whatis slice2
-// gdb-check:type = &[type_names::mod1::Enum2]
+// gdb-check:type = &mut [type_names::mod1::Enum2]
 
 // TRAITS
 // gdb-command:whatis box_trait
@@ -218,8 +218,8 @@
 // cdb-check:struct alloc::vec::Vec<usize,alloc::alloc::Global> vec1 = [...]
 // cdb-check:struct alloc::vec::Vec<enum2$<type_names::mod1::Enum2>,alloc::alloc::Global> vec2 = [...]
 // cdb-command:dv /t slice*
-// cdb-check:struct slice$<usize> slice1 = [...]
-// cdb-check:struct slice$<enum2$<type_names::mod1::Enum2> > slice2 = [...]
+// cdb-check:struct ref$<slice2$<usize> > slice1 = [...]
+// cdb-check:struct ref_mut$<slice2$<enum2$<type_names::mod1::Enum2> > > slice2 = [...]
 
 // TRAITS
 // cdb-command:dv /t *_trait
@@ -417,8 +417,8 @@ fn main() {
 
     let vec1 = vec![0_usize, 2, 3];
     let slice1 = &*vec1;
-    let vec2 = vec![mod1::Enum2::Variant2(Struct1)];
-    let slice2 = &*vec2;
+    let mut vec2 = vec![mod1::Enum2::Variant2(Struct1)];
+    let slice2 = &mut *vec2;
 
     // Trait Objects
     let box_trait = Box::new(0_isize) as Box<dyn Trait1>;
diff --git a/src/test/debuginfo/unsized.rs b/src/test/debuginfo/unsized.rs
index 7cb0002ca512..b1ec9b068305 100644
--- a/src/test/debuginfo/unsized.rs
+++ b/src/test/debuginfo/unsized.rs
@@ -32,13 +32,13 @@
 
 // cdb-command: g
 // cdb-command:dx a
-// cdb-check:a                [Type: ref$<unsized::Foo<slice$<u8> > >]
-// cdb-check:    [+0x000] data_ptr         : 0x[...] [Type: unsized::Foo<slice$<u8> > *]
+// cdb-check:a                [Type: ref$<unsized::Foo<slice2$<u8> > >]
+// cdb-check:    [+0x000] data_ptr         : 0x[...] [Type: unsized::Foo<slice2$<u8> > *]
 // cdb-check:    [...] length           : 0x4 [Type: unsigned [...]int[...]
 
 // cdb-command:dx b
-// cdb-check:b                [Type: ref$<unsized::Foo<unsized::Foo<slice$<u8> > > >]
-// cdb-check:    [+0x000] data_ptr         : 0x[...] [Type: unsized::Foo<unsized::Foo<slice$<u8> > > *]
+// cdb-check:b                [Type: ref$<unsized::Foo<unsized::Foo<slice2$<u8> > > >]
+// cdb-check:    [+0x000] data_ptr         : 0x[...] [Type: unsized::Foo<unsized::Foo<slice2$<u8> > > *]
 // cdb-check:    [...] length           : 0x4 [Type: unsigned [...]int[...]
 
 // cdb-command:dx c
@@ -53,8 +53,8 @@
 // cdb-check:[...] vtable           : 0x[...] [Type: unsigned [...]int[...] (*)[3]]
 
 // cdb-command:dx tuple_slice
-// cdb-check:tuple_slice      [Type: ref$<tuple$<i32,i32,slice$<i32> > >]
-// cdb-check:    [+0x000] data_ptr         : 0x[...] [Type: tuple$<i32,i32,slice$<i32> > *]
+// cdb-check:tuple_slice      [Type: ref$<tuple$<i32,i32,slice2$<i32> > >]
+// cdb-check:    [+0x000] data_ptr         : 0x[...] [Type: tuple$<i32,i32,slice2$<i32> > *]
 // cdb-check:    [...] length           : 0x2 [Type: unsigned [...]int[...]
 
 // cdb-command:dx tuple_dyn
diff --git a/src/test/incremental/hashes/extern_mods.rs b/src/test/incremental/hashes/extern_mods.rs
index ff79acc7f639..3121abbea369 100644
--- a/src/test/incremental/hashes/extern_mods.rs
+++ b/src/test/incremental/hashes/extern_mods.rs
@@ -128,7 +128,7 @@ extern "C" {
 // Change calling convention ---------------------------------------------------
 #[cfg(any(cfail1,cfail4))]
 extern "C" {
-    pub fn change_calling_convention(c: i32);
+    pub fn change_calling_convention(c: (i32,));
 }
 
 #[cfg(not(any(cfail1,cfail4)))]
@@ -137,7 +137,7 @@ extern "C" {
 #[rustc_clean(cfg = "cfail5", except = "hir_owner,hir_owner_nodes")]
 #[rustc_clean(cfg = "cfail6")]
 extern "rust-call" {
-    pub fn change_calling_convention(c: i32);
+    pub fn change_calling_convention(c: (i32,));
 }
 
 // Make function public --------------------------------------------------------
diff --git a/src/test/incremental/issue-101518.rs b/src/test/incremental/issue-101518.rs
new file mode 100644
index 000000000000..501be175fce5
--- /dev/null
+++ b/src/test/incremental/issue-101518.rs
@@ -0,0 +1,31 @@
+// revisions: cfail1
+// should-ice
+// error-pattern: forcing query
+// known-bug: #101518
+
+#[derive(PartialEq, Eq)]
+struct Id<'a> {
+    ns: &'a str,
+}
+fn visit_struct() {
+    let id = Id { ns: "random1" };
+    const FLAG: Id<'static> = Id {
+        ns: "needs_to_be_the_same",
+    };
+    match id {
+        FLAG => {}
+        _ => {}
+    }
+}
+fn visit_struct2() {
+    let id = Id { ns: "random2" };
+    const FLAG: Id<'static> = Id {
+        ns: "needs_to_be_the_same",
+    };
+    match id {
+        FLAG => {}
+        _ => {}
+    }
+}
+
+fn main() {}
diff --git a/src/test/mir-opt/address_of.address_of_reborrow.SimplifyCfg-initial.after.mir b/src/test/mir-opt/address_of.address_of_reborrow.SimplifyCfg-initial.after.mir
index d41a66871cc4..5f8b2f9312b7 100644
--- a/src/test/mir-opt/address_of.address_of_reborrow.SimplifyCfg-initial.after.mir
+++ b/src/test/mir-opt/address_of.address_of_reborrow.SimplifyCfg-initial.after.mir
@@ -1,115 +1,115 @@
 // MIR for `address_of_reborrow` after SimplifyCfg-initial
 
 | User Type Annotations
-| 0: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }], value: Ty(*const ^0) }, span: $DIR/address-of.rs:7:5: 7:18, inferred_ty: *const [i32; 10]
-| 1: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }], value: Ty(*const dyn std::marker::Send) }, span: $DIR/address-of.rs:9:5: 9:25, inferred_ty: *const dyn std::marker::Send
-| 2: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }], value: Ty(*const ^0) }, span: $DIR/address-of.rs:13:12: 13:20, inferred_ty: *const [i32; 10]
-| 3: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }], value: Ty(*const ^0) }, span: $DIR/address-of.rs:13:12: 13:20, inferred_ty: *const [i32; 10]
-| 4: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*const [i32; 10]) }, span: $DIR/address-of.rs:14:12: 14:28, inferred_ty: *const [i32; 10]
-| 5: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*const [i32; 10]) }, span: $DIR/address-of.rs:14:12: 14:28, inferred_ty: *const [i32; 10]
-| 6: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }], value: Ty(*const dyn std::marker::Send) }, span: $DIR/address-of.rs:15:12: 15:27, inferred_ty: *const dyn std::marker::Send
-| 7: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }], value: Ty(*const dyn std::marker::Send) }, span: $DIR/address-of.rs:15:12: 15:27, inferred_ty: *const dyn std::marker::Send
-| 8: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*const [i32]) }, span: $DIR/address-of.rs:16:12: 16:24, inferred_ty: *const [i32]
-| 9: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*const [i32]) }, span: $DIR/address-of.rs:16:12: 16:24, inferred_ty: *const [i32]
-| 10: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }], value: Ty(*const ^0) }, span: $DIR/address-of.rs:18:5: 18:18, inferred_ty: *const [i32; 10]
-| 11: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }], value: Ty(*const dyn std::marker::Send) }, span: $DIR/address-of.rs:20:5: 20:25, inferred_ty: *const dyn std::marker::Send
-| 12: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }], value: Ty(*const ^0) }, span: $DIR/address-of.rs:23:12: 23:20, inferred_ty: *const [i32; 10]
-| 13: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }], value: Ty(*const ^0) }, span: $DIR/address-of.rs:23:12: 23:20, inferred_ty: *const [i32; 10]
-| 14: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*const [i32; 10]) }, span: $DIR/address-of.rs:24:12: 24:28, inferred_ty: *const [i32; 10]
-| 15: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*const [i32; 10]) }, span: $DIR/address-of.rs:24:12: 24:28, inferred_ty: *const [i32; 10]
-| 16: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }], value: Ty(*const dyn std::marker::Send) }, span: $DIR/address-of.rs:25:12: 25:27, inferred_ty: *const dyn std::marker::Send
-| 17: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }], value: Ty(*const dyn std::marker::Send) }, span: $DIR/address-of.rs:25:12: 25:27, inferred_ty: *const dyn std::marker::Send
-| 18: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*const [i32]) }, span: $DIR/address-of.rs:26:12: 26:24, inferred_ty: *const [i32]
-| 19: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*const [i32]) }, span: $DIR/address-of.rs:26:12: 26:24, inferred_ty: *const [i32]
-| 20: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }], value: Ty(*mut ^0) }, span: $DIR/address-of.rs:28:5: 28:16, inferred_ty: *mut [i32; 10]
-| 21: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }], value: Ty(*mut dyn std::marker::Send) }, span: $DIR/address-of.rs:30:5: 30:23, inferred_ty: *mut dyn std::marker::Send
-| 22: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }], value: Ty(*mut ^0) }, span: $DIR/address-of.rs:33:12: 33:18, inferred_ty: *mut [i32; 10]
-| 23: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }], value: Ty(*mut ^0) }, span: $DIR/address-of.rs:33:12: 33:18, inferred_ty: *mut [i32; 10]
-| 24: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*mut [i32; 10]) }, span: $DIR/address-of.rs:34:12: 34:26, inferred_ty: *mut [i32; 10]
-| 25: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*mut [i32; 10]) }, span: $DIR/address-of.rs:34:12: 34:26, inferred_ty: *mut [i32; 10]
-| 26: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }], value: Ty(*mut dyn std::marker::Send) }, span: $DIR/address-of.rs:35:12: 35:25, inferred_ty: *mut dyn std::marker::Send
-| 27: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }], value: Ty(*mut dyn std::marker::Send) }, span: $DIR/address-of.rs:35:12: 35:25, inferred_ty: *mut dyn std::marker::Send
-| 28: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*mut [i32]) }, span: $DIR/address-of.rs:36:12: 36:22, inferred_ty: *mut [i32]
-| 29: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*mut [i32]) }, span: $DIR/address-of.rs:36:12: 36:22, inferred_ty: *mut [i32]
+| 0: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }], value: Ty(*const ^0) }, span: $DIR/address_of.rs:7:5: 7:18, inferred_ty: *const [i32; 10]
+| 1: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }], value: Ty(*const dyn std::marker::Send) }, span: $DIR/address_of.rs:9:5: 9:25, inferred_ty: *const dyn std::marker::Send
+| 2: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }], value: Ty(*const ^0) }, span: $DIR/address_of.rs:13:12: 13:20, inferred_ty: *const [i32; 10]
+| 3: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }], value: Ty(*const ^0) }, span: $DIR/address_of.rs:13:12: 13:20, inferred_ty: *const [i32; 10]
+| 4: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*const [i32; 10]) }, span: $DIR/address_of.rs:14:12: 14:28, inferred_ty: *const [i32; 10]
+| 5: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*const [i32; 10]) }, span: $DIR/address_of.rs:14:12: 14:28, inferred_ty: *const [i32; 10]
+| 6: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }], value: Ty(*const dyn std::marker::Send) }, span: $DIR/address_of.rs:15:12: 15:27, inferred_ty: *const dyn std::marker::Send
+| 7: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }], value: Ty(*const dyn std::marker::Send) }, span: $DIR/address_of.rs:15:12: 15:27, inferred_ty: *const dyn std::marker::Send
+| 8: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*const [i32]) }, span: $DIR/address_of.rs:16:12: 16:24, inferred_ty: *const [i32]
+| 9: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*const [i32]) }, span: $DIR/address_of.rs:16:12: 16:24, inferred_ty: *const [i32]
+| 10: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }], value: Ty(*const ^0) }, span: $DIR/address_of.rs:18:5: 18:18, inferred_ty: *const [i32; 10]
+| 11: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }], value: Ty(*const dyn std::marker::Send) }, span: $DIR/address_of.rs:20:5: 20:25, inferred_ty: *const dyn std::marker::Send
+| 12: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }], value: Ty(*const ^0) }, span: $DIR/address_of.rs:23:12: 23:20, inferred_ty: *const [i32; 10]
+| 13: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }], value: Ty(*const ^0) }, span: $DIR/address_of.rs:23:12: 23:20, inferred_ty: *const [i32; 10]
+| 14: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*const [i32; 10]) }, span: $DIR/address_of.rs:24:12: 24:28, inferred_ty: *const [i32; 10]
+| 15: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*const [i32; 10]) }, span: $DIR/address_of.rs:24:12: 24:28, inferred_ty: *const [i32; 10]
+| 16: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }], value: Ty(*const dyn std::marker::Send) }, span: $DIR/address_of.rs:25:12: 25:27, inferred_ty: *const dyn std::marker::Send
+| 17: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }], value: Ty(*const dyn std::marker::Send) }, span: $DIR/address_of.rs:25:12: 25:27, inferred_ty: *const dyn std::marker::Send
+| 18: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*const [i32]) }, span: $DIR/address_of.rs:26:12: 26:24, inferred_ty: *const [i32]
+| 19: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*const [i32]) }, span: $DIR/address_of.rs:26:12: 26:24, inferred_ty: *const [i32]
+| 20: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }], value: Ty(*mut ^0) }, span: $DIR/address_of.rs:28:5: 28:16, inferred_ty: *mut [i32; 10]
+| 21: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }], value: Ty(*mut dyn std::marker::Send) }, span: $DIR/address_of.rs:30:5: 30:23, inferred_ty: *mut dyn std::marker::Send
+| 22: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }], value: Ty(*mut ^0) }, span: $DIR/address_of.rs:33:12: 33:18, inferred_ty: *mut [i32; 10]
+| 23: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Ty(General(U0)) }], value: Ty(*mut ^0) }, span: $DIR/address_of.rs:33:12: 33:18, inferred_ty: *mut [i32; 10]
+| 24: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*mut [i32; 10]) }, span: $DIR/address_of.rs:34:12: 34:26, inferred_ty: *mut [i32; 10]
+| 25: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*mut [i32; 10]) }, span: $DIR/address_of.rs:34:12: 34:26, inferred_ty: *mut [i32; 10]
+| 26: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }], value: Ty(*mut dyn std::marker::Send) }, span: $DIR/address_of.rs:35:12: 35:25, inferred_ty: *mut dyn std::marker::Send
+| 27: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }], value: Ty(*mut dyn std::marker::Send) }, span: $DIR/address_of.rs:35:12: 35:25, inferred_ty: *mut dyn std::marker::Send
+| 28: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*mut [i32]) }, span: $DIR/address_of.rs:36:12: 36:22, inferred_ty: *mut [i32]
+| 29: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*mut [i32]) }, span: $DIR/address_of.rs:36:12: 36:22, inferred_ty: *mut [i32]
 |
 fn address_of_reborrow() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/address-of.rs:+0:26: +0:26
-    let _1: &[i32; 10];                  // in scope 0 at $DIR/address-of.rs:+1:9: +1:10
-    let _2: [i32; 10];                   // in scope 0 at $DIR/address-of.rs:+1:14: +1:21
-    let mut _4: [i32; 10];               // in scope 0 at $DIR/address-of.rs:+2:22: +2:29
-    let _5: *const [i32; 10];            // in scope 0 at $DIR/address-of.rs:+4:5: +4:18
-    let mut _6: *const [i32; 10];        // in scope 0 at $DIR/address-of.rs:+4:5: +4:18
-    let _7: *const [i32; 10];            // in scope 0 at $DIR/address-of.rs:+5:5: +5:26
-    let _8: *const dyn std::marker::Send; // in scope 0 at $DIR/address-of.rs:+6:5: +6:25
-    let mut _9: *const dyn std::marker::Send; // in scope 0 at $DIR/address-of.rs:+6:5: +6:25
-    let mut _10: *const [i32; 10];       // in scope 0 at $DIR/address-of.rs:+6:5: +6:6
-    let _11: *const [i32];               // in scope 0 at $DIR/address-of.rs:+7:5: +7:22
-    let mut _12: *const [i32; 10];       // in scope 0 at $DIR/address-of.rs:+7:5: +7:6
-    let _13: *const i32;                 // in scope 0 at $DIR/address-of.rs:+8:5: +8:20
-    let mut _14: *const [i32; 10];       // in scope 0 at $DIR/address-of.rs:+8:5: +8:6
-    let mut _18: *const [i32; 10];       // in scope 0 at $DIR/address-of.rs:+12:30: +12:31
-    let mut _20: *const [i32; 10];       // in scope 0 at $DIR/address-of.rs:+13:27: +13:28
-    let _21: *const [i32; 10];           // in scope 0 at $DIR/address-of.rs:+15:5: +15:18
-    let mut _22: *const [i32; 10];       // in scope 0 at $DIR/address-of.rs:+15:5: +15:18
-    let _23: *const [i32; 10];           // in scope 0 at $DIR/address-of.rs:+16:5: +16:26
-    let _24: *const dyn std::marker::Send; // in scope 0 at $DIR/address-of.rs:+17:5: +17:25
-    let mut _25: *const dyn std::marker::Send; // in scope 0 at $DIR/address-of.rs:+17:5: +17:25
-    let mut _26: *const [i32; 10];       // in scope 0 at $DIR/address-of.rs:+17:5: +17:6
-    let _27: *const [i32];               // in scope 0 at $DIR/address-of.rs:+18:5: +18:22
-    let mut _28: *const [i32; 10];       // in scope 0 at $DIR/address-of.rs:+18:5: +18:6
-    let mut _32: *const [i32; 10];       // in scope 0 at $DIR/address-of.rs:+22:30: +22:31
-    let mut _34: *const [i32; 10];       // in scope 0 at $DIR/address-of.rs:+23:27: +23:28
-    let _35: *mut [i32; 10];             // in scope 0 at $DIR/address-of.rs:+25:5: +25:16
-    let mut _36: *mut [i32; 10];         // in scope 0 at $DIR/address-of.rs:+25:5: +25:16
-    let _37: *mut [i32; 10];             // in scope 0 at $DIR/address-of.rs:+26:5: +26:24
-    let _38: *mut dyn std::marker::Send; // in scope 0 at $DIR/address-of.rs:+27:5: +27:23
-    let mut _39: *mut dyn std::marker::Send; // in scope 0 at $DIR/address-of.rs:+27:5: +27:23
-    let mut _40: *mut [i32; 10];         // in scope 0 at $DIR/address-of.rs:+27:5: +27:6
-    let _41: *mut [i32];                 // in scope 0 at $DIR/address-of.rs:+28:5: +28:20
-    let mut _42: *mut [i32; 10];         // in scope 0 at $DIR/address-of.rs:+28:5: +28:6
-    let mut _46: *mut [i32; 10];         // in scope 0 at $DIR/address-of.rs:+32:28: +32:29
-    let mut _48: *mut [i32; 10];         // in scope 0 at $DIR/address-of.rs:+33:25: +33:26
+    let mut _0: ();                      // return place in scope 0 at $DIR/address_of.rs:+0:26: +0:26
+    let _1: &[i32; 10];                  // in scope 0 at $DIR/address_of.rs:+1:9: +1:10
+    let _2: [i32; 10];                   // in scope 0 at $DIR/address_of.rs:+1:14: +1:21
+    let mut _4: [i32; 10];               // in scope 0 at $DIR/address_of.rs:+2:22: +2:29
+    let _5: *const [i32; 10];            // in scope 0 at $DIR/address_of.rs:+4:5: +4:18
+    let mut _6: *const [i32; 10];        // in scope 0 at $DIR/address_of.rs:+4:5: +4:18
+    let _7: *const [i32; 10];            // in scope 0 at $DIR/address_of.rs:+5:5: +5:26
+    let _8: *const dyn std::marker::Send; // in scope 0 at $DIR/address_of.rs:+6:5: +6:25
+    let mut _9: *const dyn std::marker::Send; // in scope 0 at $DIR/address_of.rs:+6:5: +6:25
+    let mut _10: *const [i32; 10];       // in scope 0 at $DIR/address_of.rs:+6:5: +6:6
+    let _11: *const [i32];               // in scope 0 at $DIR/address_of.rs:+7:5: +7:22
+    let mut _12: *const [i32; 10];       // in scope 0 at $DIR/address_of.rs:+7:5: +7:6
+    let _13: *const i32;                 // in scope 0 at $DIR/address_of.rs:+8:5: +8:20
+    let mut _14: *const [i32; 10];       // in scope 0 at $DIR/address_of.rs:+8:5: +8:6
+    let mut _18: *const [i32; 10];       // in scope 0 at $DIR/address_of.rs:+12:30: +12:31
+    let mut _20: *const [i32; 10];       // in scope 0 at $DIR/address_of.rs:+13:27: +13:28
+    let _21: *const [i32; 10];           // in scope 0 at $DIR/address_of.rs:+15:5: +15:18
+    let mut _22: *const [i32; 10];       // in scope 0 at $DIR/address_of.rs:+15:5: +15:18
+    let _23: *const [i32; 10];           // in scope 0 at $DIR/address_of.rs:+16:5: +16:26
+    let _24: *const dyn std::marker::Send; // in scope 0 at $DIR/address_of.rs:+17:5: +17:25
+    let mut _25: *const dyn std::marker::Send; // in scope 0 at $DIR/address_of.rs:+17:5: +17:25
+    let mut _26: *const [i32; 10];       // in scope 0 at $DIR/address_of.rs:+17:5: +17:6
+    let _27: *const [i32];               // in scope 0 at $DIR/address_of.rs:+18:5: +18:22
+    let mut _28: *const [i32; 10];       // in scope 0 at $DIR/address_of.rs:+18:5: +18:6
+    let mut _32: *const [i32; 10];       // in scope 0 at $DIR/address_of.rs:+22:30: +22:31
+    let mut _34: *const [i32; 10];       // in scope 0 at $DIR/address_of.rs:+23:27: +23:28
+    let _35: *mut [i32; 10];             // in scope 0 at $DIR/address_of.rs:+25:5: +25:16
+    let mut _36: *mut [i32; 10];         // in scope 0 at $DIR/address_of.rs:+25:5: +25:16
+    let _37: *mut [i32; 10];             // in scope 0 at $DIR/address_of.rs:+26:5: +26:24
+    let _38: *mut dyn std::marker::Send; // in scope 0 at $DIR/address_of.rs:+27:5: +27:23
+    let mut _39: *mut dyn std::marker::Send; // in scope 0 at $DIR/address_of.rs:+27:5: +27:23
+    let mut _40: *mut [i32; 10];         // in scope 0 at $DIR/address_of.rs:+27:5: +27:6
+    let _41: *mut [i32];                 // in scope 0 at $DIR/address_of.rs:+28:5: +28:20
+    let mut _42: *mut [i32; 10];         // in scope 0 at $DIR/address_of.rs:+28:5: +28:6
+    let mut _46: *mut [i32; 10];         // in scope 0 at $DIR/address_of.rs:+32:28: +32:29
+    let mut _48: *mut [i32; 10];         // in scope 0 at $DIR/address_of.rs:+33:25: +33:26
     scope 1 {
-        debug y => _1;                   // in scope 1 at $DIR/address-of.rs:+1:9: +1:10
-        let mut _3: &mut [i32; 10];      // in scope 1 at $DIR/address-of.rs:+2:9: +2:14
+        debug y => _1;                   // in scope 1 at $DIR/address_of.rs:+1:9: +1:10
+        let mut _3: &mut [i32; 10];      // in scope 1 at $DIR/address_of.rs:+2:9: +2:14
         scope 2 {
-            debug z => _3;               // in scope 2 at $DIR/address-of.rs:+2:9: +2:14
-            let _15: *const [i32; 10] as UserTypeProjection { base: UserType(2), projs: [] }; // in scope 2 at $DIR/address-of.rs:+10:9: +10:10
+            debug z => _3;               // in scope 2 at $DIR/address_of.rs:+2:9: +2:14
+            let _15: *const [i32; 10] as UserTypeProjection { base: UserType(2), projs: [] }; // in scope 2 at $DIR/address_of.rs:+10:9: +10:10
             scope 3 {
-                debug p => _15;          // in scope 3 at $DIR/address-of.rs:+10:9: +10:10
-                let _16: *const [i32; 10] as UserTypeProjection { base: UserType(4), projs: [] }; // in scope 3 at $DIR/address-of.rs:+11:9: +11:10
+                debug p => _15;          // in scope 3 at $DIR/address_of.rs:+10:9: +10:10
+                let _16: *const [i32; 10] as UserTypeProjection { base: UserType(4), projs: [] }; // in scope 3 at $DIR/address_of.rs:+11:9: +11:10
                 scope 4 {
-                    debug p => _16;      // in scope 4 at $DIR/address-of.rs:+11:9: +11:10
-                    let _17: *const dyn std::marker::Send as UserTypeProjection { base: UserType(6), projs: [] }; // in scope 4 at $DIR/address-of.rs:+12:9: +12:10
+                    debug p => _16;      // in scope 4 at $DIR/address_of.rs:+11:9: +11:10
+                    let _17: *const dyn std::marker::Send as UserTypeProjection { base: UserType(6), projs: [] }; // in scope 4 at $DIR/address_of.rs:+12:9: +12:10
                     scope 5 {
-                        debug p => _17;  // in scope 5 at $DIR/address-of.rs:+12:9: +12:10
-                        let _19: *const [i32] as UserTypeProjection { base: UserType(8), projs: [] }; // in scope 5 at $DIR/address-of.rs:+13:9: +13:10
+                        debug p => _17;  // in scope 5 at $DIR/address_of.rs:+12:9: +12:10
+                        let _19: *const [i32] as UserTypeProjection { base: UserType(8), projs: [] }; // in scope 5 at $DIR/address_of.rs:+13:9: +13:10
                         scope 6 {
-                            debug p => _19; // in scope 6 at $DIR/address-of.rs:+13:9: +13:10
-                            let _29: *const [i32; 10] as UserTypeProjection { base: UserType(12), projs: [] }; // in scope 6 at $DIR/address-of.rs:+20:9: +20:10
+                            debug p => _19; // in scope 6 at $DIR/address_of.rs:+13:9: +13:10
+                            let _29: *const [i32; 10] as UserTypeProjection { base: UserType(12), projs: [] }; // in scope 6 at $DIR/address_of.rs:+20:9: +20:10
                             scope 7 {
-                                debug p => _29; // in scope 7 at $DIR/address-of.rs:+20:9: +20:10
-                                let _30: *const [i32; 10] as UserTypeProjection { base: UserType(14), projs: [] }; // in scope 7 at $DIR/address-of.rs:+21:9: +21:10
+                                debug p => _29; // in scope 7 at $DIR/address_of.rs:+20:9: +20:10
+                                let _30: *const [i32; 10] as UserTypeProjection { base: UserType(14), projs: [] }; // in scope 7 at $DIR/address_of.rs:+21:9: +21:10
                                 scope 8 {
-                                    debug p => _30; // in scope 8 at $DIR/address-of.rs:+21:9: +21:10
-                                    let _31: *const dyn std::marker::Send as UserTypeProjection { base: UserType(16), projs: [] }; // in scope 8 at $DIR/address-of.rs:+22:9: +22:10
+                                    debug p => _30; // in scope 8 at $DIR/address_of.rs:+21:9: +21:10
+                                    let _31: *const dyn std::marker::Send as UserTypeProjection { base: UserType(16), projs: [] }; // in scope 8 at $DIR/address_of.rs:+22:9: +22:10
                                     scope 9 {
-                                        debug p => _31; // in scope 9 at $DIR/address-of.rs:+22:9: +22:10
-                                        let _33: *const [i32] as UserTypeProjection { base: UserType(18), projs: [] }; // in scope 9 at $DIR/address-of.rs:+23:9: +23:10
+                                        debug p => _31; // in scope 9 at $DIR/address_of.rs:+22:9: +22:10
+                                        let _33: *const [i32] as UserTypeProjection { base: UserType(18), projs: [] }; // in scope 9 at $DIR/address_of.rs:+23:9: +23:10
                                         scope 10 {
-                                            debug p => _33; // in scope 10 at $DIR/address-of.rs:+23:9: +23:10
-                                            let _43: *mut [i32; 10] as UserTypeProjection { base: UserType(22), projs: [] }; // in scope 10 at $DIR/address-of.rs:+30:9: +30:10
+                                            debug p => _33; // in scope 10 at $DIR/address_of.rs:+23:9: +23:10
+                                            let _43: *mut [i32; 10] as UserTypeProjection { base: UserType(22), projs: [] }; // in scope 10 at $DIR/address_of.rs:+30:9: +30:10
                                             scope 11 {
-                                                debug p => _43; // in scope 11 at $DIR/address-of.rs:+30:9: +30:10
-                                                let _44: *mut [i32; 10] as UserTypeProjection { base: UserType(24), projs: [] }; // in scope 11 at $DIR/address-of.rs:+31:9: +31:10
+                                                debug p => _43; // in scope 11 at $DIR/address_of.rs:+30:9: +30:10
+                                                let _44: *mut [i32; 10] as UserTypeProjection { base: UserType(24), projs: [] }; // in scope 11 at $DIR/address_of.rs:+31:9: +31:10
                                                 scope 12 {
-                                                    debug p => _44; // in scope 12 at $DIR/address-of.rs:+31:9: +31:10
-                                                    let _45: *mut dyn std::marker::Send as UserTypeProjection { base: UserType(26), projs: [] }; // in scope 12 at $DIR/address-of.rs:+32:9: +32:10
+                                                    debug p => _44; // in scope 12 at $DIR/address_of.rs:+31:9: +31:10
+                                                    let _45: *mut dyn std::marker::Send as UserTypeProjection { base: UserType(26), projs: [] }; // in scope 12 at $DIR/address_of.rs:+32:9: +32:10
                                                     scope 13 {
-                                                        debug p => _45; // in scope 13 at $DIR/address-of.rs:+32:9: +32:10
-                                                        let _47: *mut [i32] as UserTypeProjection { base: UserType(28), projs: [] }; // in scope 13 at $DIR/address-of.rs:+33:9: +33:10
+                                                        debug p => _45; // in scope 13 at $DIR/address_of.rs:+32:9: +32:10
+                                                        let _47: *mut [i32] as UserTypeProjection { base: UserType(28), projs: [] }; // in scope 13 at $DIR/address_of.rs:+33:9: +33:10
                                                         scope 14 {
-                                                            debug p => _47; // in scope 14 at $DIR/address-of.rs:+33:9: +33:10
+                                                            debug p => _47; // in scope 14 at $DIR/address_of.rs:+33:9: +33:10
                                                         }
                                                     }
                                                 }
@@ -126,183 +126,183 @@ fn address_of_reborrow() -> () {
     }
 
     bb0: {
-        StorageLive(_1);                 // scope 0 at $DIR/address-of.rs:+1:9: +1:10
-        StorageLive(_2);                 // scope 0 at $DIR/address-of.rs:+1:14: +1:21
-        _2 = [const 0_i32; 10];          // scope 0 at $DIR/address-of.rs:+1:14: +1:21
-        _1 = &_2;                        // scope 0 at $DIR/address-of.rs:+1:13: +1:21
-        FakeRead(ForLet(None), _1);      // scope 0 at $DIR/address-of.rs:+1:9: +1:10
-        StorageLive(_3);                 // scope 1 at $DIR/address-of.rs:+2:9: +2:14
-        StorageLive(_4);                 // scope 1 at $DIR/address-of.rs:+2:22: +2:29
-        _4 = [const 0_i32; 10];          // scope 1 at $DIR/address-of.rs:+2:22: +2:29
-        _3 = &mut _4;                    // scope 1 at $DIR/address-of.rs:+2:17: +2:29
-        FakeRead(ForLet(None), _3);      // scope 1 at $DIR/address-of.rs:+2:9: +2:14
-        StorageLive(_5);                 // scope 2 at $DIR/address-of.rs:+4:5: +4:18
-        StorageLive(_6);                 // scope 2 at $DIR/address-of.rs:+4:5: +4:18
-        _6 = &raw const (*_1);           // scope 2 at $DIR/address-of.rs:+4:5: +4:6
-        AscribeUserType(_6, o, UserTypeProjection { base: UserType(0), projs: [] }); // scope 2 at $DIR/address-of.rs:+4:5: +4:18
-        _5 = _6;                         // scope 2 at $DIR/address-of.rs:+4:5: +4:18
-        StorageDead(_6);                 // scope 2 at $DIR/address-of.rs:+4:18: +4:19
-        StorageDead(_5);                 // scope 2 at $DIR/address-of.rs:+4:18: +4:19
-        StorageLive(_7);                 // scope 2 at $DIR/address-of.rs:+5:5: +5:26
-        _7 = &raw const (*_1);           // scope 2 at $DIR/address-of.rs:+5:5: +5:6
-        StorageDead(_7);                 // scope 2 at $DIR/address-of.rs:+5:26: +5:27
-        StorageLive(_8);                 // scope 2 at $DIR/address-of.rs:+6:5: +6:25
-        StorageLive(_9);                 // scope 2 at $DIR/address-of.rs:+6:5: +6:25
-        StorageLive(_10);                // scope 2 at $DIR/address-of.rs:+6:5: +6:6
-        _10 = &raw const (*_1);          // scope 2 at $DIR/address-of.rs:+6:5: +6:6
-        _9 = move _10 as *const dyn std::marker::Send (Pointer(Unsize)); // scope 2 at $DIR/address-of.rs:+6:5: +6:6
-        StorageDead(_10);                // scope 2 at $DIR/address-of.rs:+6:5: +6:6
-        AscribeUserType(_9, o, UserTypeProjection { base: UserType(1), projs: [] }); // scope 2 at $DIR/address-of.rs:+6:5: +6:25
-        _8 = _9;                         // scope 2 at $DIR/address-of.rs:+6:5: +6:25
-        StorageDead(_9);                 // scope 2 at $DIR/address-of.rs:+6:25: +6:26
-        StorageDead(_8);                 // scope 2 at $DIR/address-of.rs:+6:25: +6:26
-        StorageLive(_11);                // scope 2 at $DIR/address-of.rs:+7:5: +7:22
-        StorageLive(_12);                // scope 2 at $DIR/address-of.rs:+7:5: +7:6
-        _12 = &raw const (*_1);          // scope 2 at $DIR/address-of.rs:+7:5: +7:6
-        _11 = move _12 as *const [i32] (Pointer(Unsize)); // scope 2 at $DIR/address-of.rs:+7:5: +7:6
-        StorageDead(_12);                // scope 2 at $DIR/address-of.rs:+7:5: +7:6
-        StorageDead(_11);                // scope 2 at $DIR/address-of.rs:+7:22: +7:23
-        StorageLive(_13);                // scope 2 at $DIR/address-of.rs:+8:5: +8:20
-        StorageLive(_14);                // scope 2 at $DIR/address-of.rs:+8:5: +8:6
-        _14 = &raw const (*_1);          // scope 2 at $DIR/address-of.rs:+8:5: +8:6
-        _13 = move _14 as *const i32 (Pointer(ArrayToPointer)); // scope 2 at $DIR/address-of.rs:+8:5: +8:20
-        StorageDead(_14);                // scope 2 at $DIR/address-of.rs:+8:19: +8:20
-        StorageDead(_13);                // scope 2 at $DIR/address-of.rs:+8:20: +8:21
-        StorageLive(_15);                // scope 2 at $DIR/address-of.rs:+10:9: +10:10
-        _15 = &raw const (*_1);          // scope 2 at $DIR/address-of.rs:+10:23: +10:24
-        FakeRead(ForLet(None), _15);     // scope 2 at $DIR/address-of.rs:+10:9: +10:10
-        AscribeUserType(_15, o, UserTypeProjection { base: UserType(3), projs: [] }); // scope 2 at $DIR/address-of.rs:+10:12: +10:20
-        StorageLive(_16);                // scope 3 at $DIR/address-of.rs:+11:9: +11:10
-        _16 = &raw const (*_1);          // scope 3 at $DIR/address-of.rs:+11:31: +11:32
-        FakeRead(ForLet(None), _16);     // scope 3 at $DIR/address-of.rs:+11:9: +11:10
-        AscribeUserType(_16, o, UserTypeProjection { base: UserType(5), projs: [] }); // scope 3 at $DIR/address-of.rs:+11:12: +11:28
-        StorageLive(_17);                // scope 4 at $DIR/address-of.rs:+12:9: +12:10
-        StorageLive(_18);                // scope 4 at $DIR/address-of.rs:+12:30: +12:31
-        _18 = &raw const (*_1);          // scope 4 at $DIR/address-of.rs:+12:30: +12:31
-        _17 = move _18 as *const dyn std::marker::Send (Pointer(Unsize)); // scope 4 at $DIR/address-of.rs:+12:30: +12:31
-        StorageDead(_18);                // scope 4 at $DIR/address-of.rs:+12:30: +12:31
-        FakeRead(ForLet(None), _17);     // scope 4 at $DIR/address-of.rs:+12:9: +12:10
-        AscribeUserType(_17, o, UserTypeProjection { base: UserType(7), projs: [] }); // scope 4 at $DIR/address-of.rs:+12:12: +12:27
-        StorageLive(_19);                // scope 5 at $DIR/address-of.rs:+13:9: +13:10
-        StorageLive(_20);                // scope 5 at $DIR/address-of.rs:+13:27: +13:28
-        _20 = &raw const (*_1);          // scope 5 at $DIR/address-of.rs:+13:27: +13:28
-        _19 = move _20 as *const [i32] (Pointer(Unsize)); // scope 5 at $DIR/address-of.rs:+13:27: +13:28
-        StorageDead(_20);                // scope 5 at $DIR/address-of.rs:+13:27: +13:28
-        FakeRead(ForLet(None), _19);     // scope 5 at $DIR/address-of.rs:+13:9: +13:10
-        AscribeUserType(_19, o, UserTypeProjection { base: UserType(9), projs: [] }); // scope 5 at $DIR/address-of.rs:+13:12: +13:24
-        StorageLive(_21);                // scope 6 at $DIR/address-of.rs:+15:5: +15:18
-        StorageLive(_22);                // scope 6 at $DIR/address-of.rs:+15:5: +15:18
-        _22 = &raw const (*_3);          // scope 6 at $DIR/address-of.rs:+15:5: +15:6
-        AscribeUserType(_22, o, UserTypeProjection { base: UserType(10), projs: [] }); // scope 6 at $DIR/address-of.rs:+15:5: +15:18
-        _21 = _22;                       // scope 6 at $DIR/address-of.rs:+15:5: +15:18
-        StorageDead(_22);                // scope 6 at $DIR/address-of.rs:+15:18: +15:19
-        StorageDead(_21);                // scope 6 at $DIR/address-of.rs:+15:18: +15:19
-        StorageLive(_23);                // scope 6 at $DIR/address-of.rs:+16:5: +16:26
-        _23 = &raw const (*_3);          // scope 6 at $DIR/address-of.rs:+16:5: +16:6
-        StorageDead(_23);                // scope 6 at $DIR/address-of.rs:+16:26: +16:27
-        StorageLive(_24);                // scope 6 at $DIR/address-of.rs:+17:5: +17:25
-        StorageLive(_25);                // scope 6 at $DIR/address-of.rs:+17:5: +17:25
-        StorageLive(_26);                // scope 6 at $DIR/address-of.rs:+17:5: +17:6
-        _26 = &raw const (*_3);          // scope 6 at $DIR/address-of.rs:+17:5: +17:6
-        _25 = move _26 as *const dyn std::marker::Send (Pointer(Unsize)); // scope 6 at $DIR/address-of.rs:+17:5: +17:6
-        StorageDead(_26);                // scope 6 at $DIR/address-of.rs:+17:5: +17:6
-        AscribeUserType(_25, o, UserTypeProjection { base: UserType(11), projs: [] }); // scope 6 at $DIR/address-of.rs:+17:5: +17:25
-        _24 = _25;                       // scope 6 at $DIR/address-of.rs:+17:5: +17:25
-        StorageDead(_25);                // scope 6 at $DIR/address-of.rs:+17:25: +17:26
-        StorageDead(_24);                // scope 6 at $DIR/address-of.rs:+17:25: +17:26
-        StorageLive(_27);                // scope 6 at $DIR/address-of.rs:+18:5: +18:22
-        StorageLive(_28);                // scope 6 at $DIR/address-of.rs:+18:5: +18:6
-        _28 = &raw const (*_3);          // scope 6 at $DIR/address-of.rs:+18:5: +18:6
-        _27 = move _28 as *const [i32] (Pointer(Unsize)); // scope 6 at $DIR/address-of.rs:+18:5: +18:6
-        StorageDead(_28);                // scope 6 at $DIR/address-of.rs:+18:5: +18:6
-        StorageDead(_27);                // scope 6 at $DIR/address-of.rs:+18:22: +18:23
-        StorageLive(_29);                // scope 6 at $DIR/address-of.rs:+20:9: +20:10
-        _29 = &raw const (*_3);          // scope 6 at $DIR/address-of.rs:+20:23: +20:24
-        FakeRead(ForLet(None), _29);     // scope 6 at $DIR/address-of.rs:+20:9: +20:10
-        AscribeUserType(_29, o, UserTypeProjection { base: UserType(13), projs: [] }); // scope 6 at $DIR/address-of.rs:+20:12: +20:20
-        StorageLive(_30);                // scope 7 at $DIR/address-of.rs:+21:9: +21:10
-        _30 = &raw const (*_3);          // scope 7 at $DIR/address-of.rs:+21:31: +21:32
-        FakeRead(ForLet(None), _30);     // scope 7 at $DIR/address-of.rs:+21:9: +21:10
-        AscribeUserType(_30, o, UserTypeProjection { base: UserType(15), projs: [] }); // scope 7 at $DIR/address-of.rs:+21:12: +21:28
-        StorageLive(_31);                // scope 8 at $DIR/address-of.rs:+22:9: +22:10
-        StorageLive(_32);                // scope 8 at $DIR/address-of.rs:+22:30: +22:31
-        _32 = &raw const (*_3);          // scope 8 at $DIR/address-of.rs:+22:30: +22:31
-        _31 = move _32 as *const dyn std::marker::Send (Pointer(Unsize)); // scope 8 at $DIR/address-of.rs:+22:30: +22:31
-        StorageDead(_32);                // scope 8 at $DIR/address-of.rs:+22:30: +22:31
-        FakeRead(ForLet(None), _31);     // scope 8 at $DIR/address-of.rs:+22:9: +22:10
-        AscribeUserType(_31, o, UserTypeProjection { base: UserType(17), projs: [] }); // scope 8 at $DIR/address-of.rs:+22:12: +22:27
-        StorageLive(_33);                // scope 9 at $DIR/address-of.rs:+23:9: +23:10
-        StorageLive(_34);                // scope 9 at $DIR/address-of.rs:+23:27: +23:28
-        _34 = &raw const (*_3);          // scope 9 at $DIR/address-of.rs:+23:27: +23:28
-        _33 = move _34 as *const [i32] (Pointer(Unsize)); // scope 9 at $DIR/address-of.rs:+23:27: +23:28
-        StorageDead(_34);                // scope 9 at $DIR/address-of.rs:+23:27: +23:28
-        FakeRead(ForLet(None), _33);     // scope 9 at $DIR/address-of.rs:+23:9: +23:10
-        AscribeUserType(_33, o, UserTypeProjection { base: UserType(19), projs: [] }); // scope 9 at $DIR/address-of.rs:+23:12: +23:24
-        StorageLive(_35);                // scope 10 at $DIR/address-of.rs:+25:5: +25:16
-        StorageLive(_36);                // scope 10 at $DIR/address-of.rs:+25:5: +25:16
-        _36 = &raw mut (*_3);            // scope 10 at $DIR/address-of.rs:+25:5: +25:6
-        AscribeUserType(_36, o, UserTypeProjection { base: UserType(20), projs: [] }); // scope 10 at $DIR/address-of.rs:+25:5: +25:16
-        _35 = _36;                       // scope 10 at $DIR/address-of.rs:+25:5: +25:16
-        StorageDead(_36);                // scope 10 at $DIR/address-of.rs:+25:16: +25:17
-        StorageDead(_35);                // scope 10 at $DIR/address-of.rs:+25:16: +25:17
-        StorageLive(_37);                // scope 10 at $DIR/address-of.rs:+26:5: +26:24
-        _37 = &raw mut (*_3);            // scope 10 at $DIR/address-of.rs:+26:5: +26:6
-        StorageDead(_37);                // scope 10 at $DIR/address-of.rs:+26:24: +26:25
-        StorageLive(_38);                // scope 10 at $DIR/address-of.rs:+27:5: +27:23
-        StorageLive(_39);                // scope 10 at $DIR/address-of.rs:+27:5: +27:23
-        StorageLive(_40);                // scope 10 at $DIR/address-of.rs:+27:5: +27:6
-        _40 = &raw mut (*_3);            // scope 10 at $DIR/address-of.rs:+27:5: +27:6
-        _39 = move _40 as *mut dyn std::marker::Send (Pointer(Unsize)); // scope 10 at $DIR/address-of.rs:+27:5: +27:6
-        StorageDead(_40);                // scope 10 at $DIR/address-of.rs:+27:5: +27:6
-        AscribeUserType(_39, o, UserTypeProjection { base: UserType(21), projs: [] }); // scope 10 at $DIR/address-of.rs:+27:5: +27:23
-        _38 = _39;                       // scope 10 at $DIR/address-of.rs:+27:5: +27:23
-        StorageDead(_39);                // scope 10 at $DIR/address-of.rs:+27:23: +27:24
-        StorageDead(_38);                // scope 10 at $DIR/address-of.rs:+27:23: +27:24
-        StorageLive(_41);                // scope 10 at $DIR/address-of.rs:+28:5: +28:20
-        StorageLive(_42);                // scope 10 at $DIR/address-of.rs:+28:5: +28:6
-        _42 = &raw mut (*_3);            // scope 10 at $DIR/address-of.rs:+28:5: +28:6
-        _41 = move _42 as *mut [i32] (Pointer(Unsize)); // scope 10 at $DIR/address-of.rs:+28:5: +28:6
-        StorageDead(_42);                // scope 10 at $DIR/address-of.rs:+28:5: +28:6
-        StorageDead(_41);                // scope 10 at $DIR/address-of.rs:+28:20: +28:21
-        StorageLive(_43);                // scope 10 at $DIR/address-of.rs:+30:9: +30:10
-        _43 = &raw mut (*_3);            // scope 10 at $DIR/address-of.rs:+30:21: +30:22
-        FakeRead(ForLet(None), _43);     // scope 10 at $DIR/address-of.rs:+30:9: +30:10
-        AscribeUserType(_43, o, UserTypeProjection { base: UserType(23), projs: [] }); // scope 10 at $DIR/address-of.rs:+30:12: +30:18
-        StorageLive(_44);                // scope 11 at $DIR/address-of.rs:+31:9: +31:10
-        _44 = &raw mut (*_3);            // scope 11 at $DIR/address-of.rs:+31:29: +31:30
-        FakeRead(ForLet(None), _44);     // scope 11 at $DIR/address-of.rs:+31:9: +31:10
-        AscribeUserType(_44, o, UserTypeProjection { base: UserType(25), projs: [] }); // scope 11 at $DIR/address-of.rs:+31:12: +31:26
-        StorageLive(_45);                // scope 12 at $DIR/address-of.rs:+32:9: +32:10
-        StorageLive(_46);                // scope 12 at $DIR/address-of.rs:+32:28: +32:29
-        _46 = &raw mut (*_3);            // scope 12 at $DIR/address-of.rs:+32:28: +32:29
-        _45 = move _46 as *mut dyn std::marker::Send (Pointer(Unsize)); // scope 12 at $DIR/address-of.rs:+32:28: +32:29
-        StorageDead(_46);                // scope 12 at $DIR/address-of.rs:+32:28: +32:29
-        FakeRead(ForLet(None), _45);     // scope 12 at $DIR/address-of.rs:+32:9: +32:10
-        AscribeUserType(_45, o, UserTypeProjection { base: UserType(27), projs: [] }); // scope 12 at $DIR/address-of.rs:+32:12: +32:25
-        StorageLive(_47);                // scope 13 at $DIR/address-of.rs:+33:9: +33:10
-        StorageLive(_48);                // scope 13 at $DIR/address-of.rs:+33:25: +33:26
-        _48 = &raw mut (*_3);            // scope 13 at $DIR/address-of.rs:+33:25: +33:26
-        _47 = move _48 as *mut [i32] (Pointer(Unsize)); // scope 13 at $DIR/address-of.rs:+33:25: +33:26
-        StorageDead(_48);                // scope 13 at $DIR/address-of.rs:+33:25: +33:26
-        FakeRead(ForLet(None), _47);     // scope 13 at $DIR/address-of.rs:+33:9: +33:10
-        AscribeUserType(_47, o, UserTypeProjection { base: UserType(29), projs: [] }); // scope 13 at $DIR/address-of.rs:+33:12: +33:22
-        _0 = const ();                   // scope 0 at $DIR/address-of.rs:+0:26: +34:2
-        StorageDead(_47);                // scope 13 at $DIR/address-of.rs:+34:1: +34:2
-        StorageDead(_45);                // scope 12 at $DIR/address-of.rs:+34:1: +34:2
-        StorageDead(_44);                // scope 11 at $DIR/address-of.rs:+34:1: +34:2
-        StorageDead(_43);                // scope 10 at $DIR/address-of.rs:+34:1: +34:2
-        StorageDead(_33);                // scope 9 at $DIR/address-of.rs:+34:1: +34:2
-        StorageDead(_31);                // scope 8 at $DIR/address-of.rs:+34:1: +34:2
-        StorageDead(_30);                // scope 7 at $DIR/address-of.rs:+34:1: +34:2
-        StorageDead(_29);                // scope 6 at $DIR/address-of.rs:+34:1: +34:2
-        StorageDead(_19);                // scope 5 at $DIR/address-of.rs:+34:1: +34:2
-        StorageDead(_17);                // scope 4 at $DIR/address-of.rs:+34:1: +34:2
-        StorageDead(_16);                // scope 3 at $DIR/address-of.rs:+34:1: +34:2
-        StorageDead(_15);                // scope 2 at $DIR/address-of.rs:+34:1: +34:2
-        StorageDead(_4);                 // scope 1 at $DIR/address-of.rs:+34:1: +34:2
-        StorageDead(_3);                 // scope 1 at $DIR/address-of.rs:+34:1: +34:2
-        StorageDead(_2);                 // scope 0 at $DIR/address-of.rs:+34:1: +34:2
-        StorageDead(_1);                 // scope 0 at $DIR/address-of.rs:+34:1: +34:2
-        return;                          // scope 0 at $DIR/address-of.rs:+34:2: +34:2
+        StorageLive(_1);                 // scope 0 at $DIR/address_of.rs:+1:9: +1:10
+        StorageLive(_2);                 // scope 0 at $DIR/address_of.rs:+1:14: +1:21
+        _2 = [const 0_i32; 10];          // scope 0 at $DIR/address_of.rs:+1:14: +1:21
+        _1 = &_2;                        // scope 0 at $DIR/address_of.rs:+1:13: +1:21
+        FakeRead(ForLet(None), _1);      // scope 0 at $DIR/address_of.rs:+1:9: +1:10
+        StorageLive(_3);                 // scope 1 at $DIR/address_of.rs:+2:9: +2:14
+        StorageLive(_4);                 // scope 1 at $DIR/address_of.rs:+2:22: +2:29
+        _4 = [const 0_i32; 10];          // scope 1 at $DIR/address_of.rs:+2:22: +2:29
+        _3 = &mut _4;                    // scope 1 at $DIR/address_of.rs:+2:17: +2:29
+        FakeRead(ForLet(None), _3);      // scope 1 at $DIR/address_of.rs:+2:9: +2:14
+        StorageLive(_5);                 // scope 2 at $DIR/address_of.rs:+4:5: +4:18
+        StorageLive(_6);                 // scope 2 at $DIR/address_of.rs:+4:5: +4:18
+        _6 = &raw const (*_1);           // scope 2 at $DIR/address_of.rs:+4:5: +4:6
+        AscribeUserType(_6, o, UserTypeProjection { base: UserType(0), projs: [] }); // scope 2 at $DIR/address_of.rs:+4:5: +4:18
+        _5 = _6;                         // scope 2 at $DIR/address_of.rs:+4:5: +4:18
+        StorageDead(_6);                 // scope 2 at $DIR/address_of.rs:+4:18: +4:19
+        StorageDead(_5);                 // scope 2 at $DIR/address_of.rs:+4:18: +4:19
+        StorageLive(_7);                 // scope 2 at $DIR/address_of.rs:+5:5: +5:26
+        _7 = &raw const (*_1);           // scope 2 at $DIR/address_of.rs:+5:5: +5:6
+        StorageDead(_7);                 // scope 2 at $DIR/address_of.rs:+5:26: +5:27
+        StorageLive(_8);                 // scope 2 at $DIR/address_of.rs:+6:5: +6:25
+        StorageLive(_9);                 // scope 2 at $DIR/address_of.rs:+6:5: +6:25
+        StorageLive(_10);                // scope 2 at $DIR/address_of.rs:+6:5: +6:6
+        _10 = &raw const (*_1);          // scope 2 at $DIR/address_of.rs:+6:5: +6:6
+        _9 = move _10 as *const dyn std::marker::Send (Pointer(Unsize)); // scope 2 at $DIR/address_of.rs:+6:5: +6:6
+        StorageDead(_10);                // scope 2 at $DIR/address_of.rs:+6:5: +6:6
+        AscribeUserType(_9, o, UserTypeProjection { base: UserType(1), projs: [] }); // scope 2 at $DIR/address_of.rs:+6:5: +6:25
+        _8 = _9;                         // scope 2 at $DIR/address_of.rs:+6:5: +6:25
+        StorageDead(_9);                 // scope 2 at $DIR/address_of.rs:+6:25: +6:26
+        StorageDead(_8);                 // scope 2 at $DIR/address_of.rs:+6:25: +6:26
+        StorageLive(_11);                // scope 2 at $DIR/address_of.rs:+7:5: +7:22
+        StorageLive(_12);                // scope 2 at $DIR/address_of.rs:+7:5: +7:6
+        _12 = &raw const (*_1);          // scope 2 at $DIR/address_of.rs:+7:5: +7:6
+        _11 = move _12 as *const [i32] (Pointer(Unsize)); // scope 2 at $DIR/address_of.rs:+7:5: +7:6
+        StorageDead(_12);                // scope 2 at $DIR/address_of.rs:+7:5: +7:6
+        StorageDead(_11);                // scope 2 at $DIR/address_of.rs:+7:22: +7:23
+        StorageLive(_13);                // scope 2 at $DIR/address_of.rs:+8:5: +8:20
+        StorageLive(_14);                // scope 2 at $DIR/address_of.rs:+8:5: +8:6
+        _14 = &raw const (*_1);          // scope 2 at $DIR/address_of.rs:+8:5: +8:6
+        _13 = move _14 as *const i32 (Pointer(ArrayToPointer)); // scope 2 at $DIR/address_of.rs:+8:5: +8:20
+        StorageDead(_14);                // scope 2 at $DIR/address_of.rs:+8:19: +8:20
+        StorageDead(_13);                // scope 2 at $DIR/address_of.rs:+8:20: +8:21
+        StorageLive(_15);                // scope 2 at $DIR/address_of.rs:+10:9: +10:10
+        _15 = &raw const (*_1);          // scope 2 at $DIR/address_of.rs:+10:23: +10:24
+        FakeRead(ForLet(None), _15);     // scope 2 at $DIR/address_of.rs:+10:9: +10:10
+        AscribeUserType(_15, o, UserTypeProjection { base: UserType(3), projs: [] }); // scope 2 at $DIR/address_of.rs:+10:12: +10:20
+        StorageLive(_16);                // scope 3 at $DIR/address_of.rs:+11:9: +11:10
+        _16 = &raw const (*_1);          // scope 3 at $DIR/address_of.rs:+11:31: +11:32
+        FakeRead(ForLet(None), _16);     // scope 3 at $DIR/address_of.rs:+11:9: +11:10
+        AscribeUserType(_16, o, UserTypeProjection { base: UserType(5), projs: [] }); // scope 3 at $DIR/address_of.rs:+11:12: +11:28
+        StorageLive(_17);                // scope 4 at $DIR/address_of.rs:+12:9: +12:10
+        StorageLive(_18);                // scope 4 at $DIR/address_of.rs:+12:30: +12:31
+        _18 = &raw const (*_1);          // scope 4 at $DIR/address_of.rs:+12:30: +12:31
+        _17 = move _18 as *const dyn std::marker::Send (Pointer(Unsize)); // scope 4 at $DIR/address_of.rs:+12:30: +12:31
+        StorageDead(_18);                // scope 4 at $DIR/address_of.rs:+12:30: +12:31
+        FakeRead(ForLet(None), _17);     // scope 4 at $DIR/address_of.rs:+12:9: +12:10
+        AscribeUserType(_17, o, UserTypeProjection { base: UserType(7), projs: [] }); // scope 4 at $DIR/address_of.rs:+12:12: +12:27
+        StorageLive(_19);                // scope 5 at $DIR/address_of.rs:+13:9: +13:10
+        StorageLive(_20);                // scope 5 at $DIR/address_of.rs:+13:27: +13:28
+        _20 = &raw const (*_1);          // scope 5 at $DIR/address_of.rs:+13:27: +13:28
+        _19 = move _20 as *const [i32] (Pointer(Unsize)); // scope 5 at $DIR/address_of.rs:+13:27: +13:28
+        StorageDead(_20);                // scope 5 at $DIR/address_of.rs:+13:27: +13:28
+        FakeRead(ForLet(None), _19);     // scope 5 at $DIR/address_of.rs:+13:9: +13:10
+        AscribeUserType(_19, o, UserTypeProjection { base: UserType(9), projs: [] }); // scope 5 at $DIR/address_of.rs:+13:12: +13:24
+        StorageLive(_21);                // scope 6 at $DIR/address_of.rs:+15:5: +15:18
+        StorageLive(_22);                // scope 6 at $DIR/address_of.rs:+15:5: +15:18
+        _22 = &raw const (*_3);          // scope 6 at $DIR/address_of.rs:+15:5: +15:6
+        AscribeUserType(_22, o, UserTypeProjection { base: UserType(10), projs: [] }); // scope 6 at $DIR/address_of.rs:+15:5: +15:18
+        _21 = _22;                       // scope 6 at $DIR/address_of.rs:+15:5: +15:18
+        StorageDead(_22);                // scope 6 at $DIR/address_of.rs:+15:18: +15:19
+        StorageDead(_21);                // scope 6 at $DIR/address_of.rs:+15:18: +15:19
+        StorageLive(_23);                // scope 6 at $DIR/address_of.rs:+16:5: +16:26
+        _23 = &raw const (*_3);          // scope 6 at $DIR/address_of.rs:+16:5: +16:6
+        StorageDead(_23);                // scope 6 at $DIR/address_of.rs:+16:26: +16:27
+        StorageLive(_24);                // scope 6 at $DIR/address_of.rs:+17:5: +17:25
+        StorageLive(_25);                // scope 6 at $DIR/address_of.rs:+17:5: +17:25
+        StorageLive(_26);                // scope 6 at $DIR/address_of.rs:+17:5: +17:6
+        _26 = &raw const (*_3);          // scope 6 at $DIR/address_of.rs:+17:5: +17:6
+        _25 = move _26 as *const dyn std::marker::Send (Pointer(Unsize)); // scope 6 at $DIR/address_of.rs:+17:5: +17:6
+        StorageDead(_26);                // scope 6 at $DIR/address_of.rs:+17:5: +17:6
+        AscribeUserType(_25, o, UserTypeProjection { base: UserType(11), projs: [] }); // scope 6 at $DIR/address_of.rs:+17:5: +17:25
+        _24 = _25;                       // scope 6 at $DIR/address_of.rs:+17:5: +17:25
+        StorageDead(_25);                // scope 6 at $DIR/address_of.rs:+17:25: +17:26
+        StorageDead(_24);                // scope 6 at $DIR/address_of.rs:+17:25: +17:26
+        StorageLive(_27);                // scope 6 at $DIR/address_of.rs:+18:5: +18:22
+        StorageLive(_28);                // scope 6 at $DIR/address_of.rs:+18:5: +18:6
+        _28 = &raw const (*_3);          // scope 6 at $DIR/address_of.rs:+18:5: +18:6
+        _27 = move _28 as *const [i32] (Pointer(Unsize)); // scope 6 at $DIR/address_of.rs:+18:5: +18:6
+        StorageDead(_28);                // scope 6 at $DIR/address_of.rs:+18:5: +18:6
+        StorageDead(_27);                // scope 6 at $DIR/address_of.rs:+18:22: +18:23
+        StorageLive(_29);                // scope 6 at $DIR/address_of.rs:+20:9: +20:10
+        _29 = &raw const (*_3);          // scope 6 at $DIR/address_of.rs:+20:23: +20:24
+        FakeRead(ForLet(None), _29);     // scope 6 at $DIR/address_of.rs:+20:9: +20:10
+        AscribeUserType(_29, o, UserTypeProjection { base: UserType(13), projs: [] }); // scope 6 at $DIR/address_of.rs:+20:12: +20:20
+        StorageLive(_30);                // scope 7 at $DIR/address_of.rs:+21:9: +21:10
+        _30 = &raw const (*_3);          // scope 7 at $DIR/address_of.rs:+21:31: +21:32
+        FakeRead(ForLet(None), _30);     // scope 7 at $DIR/address_of.rs:+21:9: +21:10
+        AscribeUserType(_30, o, UserTypeProjection { base: UserType(15), projs: [] }); // scope 7 at $DIR/address_of.rs:+21:12: +21:28
+        StorageLive(_31);                // scope 8 at $DIR/address_of.rs:+22:9: +22:10
+        StorageLive(_32);                // scope 8 at $DIR/address_of.rs:+22:30: +22:31
+        _32 = &raw const (*_3);          // scope 8 at $DIR/address_of.rs:+22:30: +22:31
+        _31 = move _32 as *const dyn std::marker::Send (Pointer(Unsize)); // scope 8 at $DIR/address_of.rs:+22:30: +22:31
+        StorageDead(_32);                // scope 8 at $DIR/address_of.rs:+22:30: +22:31
+        FakeRead(ForLet(None), _31);     // scope 8 at $DIR/address_of.rs:+22:9: +22:10
+        AscribeUserType(_31, o, UserTypeProjection { base: UserType(17), projs: [] }); // scope 8 at $DIR/address_of.rs:+22:12: +22:27
+        StorageLive(_33);                // scope 9 at $DIR/address_of.rs:+23:9: +23:10
+        StorageLive(_34);                // scope 9 at $DIR/address_of.rs:+23:27: +23:28
+        _34 = &raw const (*_3);          // scope 9 at $DIR/address_of.rs:+23:27: +23:28
+        _33 = move _34 as *const [i32] (Pointer(Unsize)); // scope 9 at $DIR/address_of.rs:+23:27: +23:28
+        StorageDead(_34);                // scope 9 at $DIR/address_of.rs:+23:27: +23:28
+        FakeRead(ForLet(None), _33);     // scope 9 at $DIR/address_of.rs:+23:9: +23:10
+        AscribeUserType(_33, o, UserTypeProjection { base: UserType(19), projs: [] }); // scope 9 at $DIR/address_of.rs:+23:12: +23:24
+        StorageLive(_35);                // scope 10 at $DIR/address_of.rs:+25:5: +25:16
+        StorageLive(_36);                // scope 10 at $DIR/address_of.rs:+25:5: +25:16
+        _36 = &raw mut (*_3);            // scope 10 at $DIR/address_of.rs:+25:5: +25:6
+        AscribeUserType(_36, o, UserTypeProjection { base: UserType(20), projs: [] }); // scope 10 at $DIR/address_of.rs:+25:5: +25:16
+        _35 = _36;                       // scope 10 at $DIR/address_of.rs:+25:5: +25:16
+        StorageDead(_36);                // scope 10 at $DIR/address_of.rs:+25:16: +25:17
+        StorageDead(_35);                // scope 10 at $DIR/address_of.rs:+25:16: +25:17
+        StorageLive(_37);                // scope 10 at $DIR/address_of.rs:+26:5: +26:24
+        _37 = &raw mut (*_3);            // scope 10 at $DIR/address_of.rs:+26:5: +26:6
+        StorageDead(_37);                // scope 10 at $DIR/address_of.rs:+26:24: +26:25
+        StorageLive(_38);                // scope 10 at $DIR/address_of.rs:+27:5: +27:23
+        StorageLive(_39);                // scope 10 at $DIR/address_of.rs:+27:5: +27:23
+        StorageLive(_40);                // scope 10 at $DIR/address_of.rs:+27:5: +27:6
+        _40 = &raw mut (*_3);            // scope 10 at $DIR/address_of.rs:+27:5: +27:6
+        _39 = move _40 as *mut dyn std::marker::Send (Pointer(Unsize)); // scope 10 at $DIR/address_of.rs:+27:5: +27:6
+        StorageDead(_40);                // scope 10 at $DIR/address_of.rs:+27:5: +27:6
+        AscribeUserType(_39, o, UserTypeProjection { base: UserType(21), projs: [] }); // scope 10 at $DIR/address_of.rs:+27:5: +27:23
+        _38 = _39;                       // scope 10 at $DIR/address_of.rs:+27:5: +27:23
+        StorageDead(_39);                // scope 10 at $DIR/address_of.rs:+27:23: +27:24
+        StorageDead(_38);                // scope 10 at $DIR/address_of.rs:+27:23: +27:24
+        StorageLive(_41);                // scope 10 at $DIR/address_of.rs:+28:5: +28:20
+        StorageLive(_42);                // scope 10 at $DIR/address_of.rs:+28:5: +28:6
+        _42 = &raw mut (*_3);            // scope 10 at $DIR/address_of.rs:+28:5: +28:6
+        _41 = move _42 as *mut [i32] (Pointer(Unsize)); // scope 10 at $DIR/address_of.rs:+28:5: +28:6
+        StorageDead(_42);                // scope 10 at $DIR/address_of.rs:+28:5: +28:6
+        StorageDead(_41);                // scope 10 at $DIR/address_of.rs:+28:20: +28:21
+        StorageLive(_43);                // scope 10 at $DIR/address_of.rs:+30:9: +30:10
+        _43 = &raw mut (*_3);            // scope 10 at $DIR/address_of.rs:+30:21: +30:22
+        FakeRead(ForLet(None), _43);     // scope 10 at $DIR/address_of.rs:+30:9: +30:10
+        AscribeUserType(_43, o, UserTypeProjection { base: UserType(23), projs: [] }); // scope 10 at $DIR/address_of.rs:+30:12: +30:18
+        StorageLive(_44);                // scope 11 at $DIR/address_of.rs:+31:9: +31:10
+        _44 = &raw mut (*_3);            // scope 11 at $DIR/address_of.rs:+31:29: +31:30
+        FakeRead(ForLet(None), _44);     // scope 11 at $DIR/address_of.rs:+31:9: +31:10
+        AscribeUserType(_44, o, UserTypeProjection { base: UserType(25), projs: [] }); // scope 11 at $DIR/address_of.rs:+31:12: +31:26
+        StorageLive(_45);                // scope 12 at $DIR/address_of.rs:+32:9: +32:10
+        StorageLive(_46);                // scope 12 at $DIR/address_of.rs:+32:28: +32:29
+        _46 = &raw mut (*_3);            // scope 12 at $DIR/address_of.rs:+32:28: +32:29
+        _45 = move _46 as *mut dyn std::marker::Send (Pointer(Unsize)); // scope 12 at $DIR/address_of.rs:+32:28: +32:29
+        StorageDead(_46);                // scope 12 at $DIR/address_of.rs:+32:28: +32:29
+        FakeRead(ForLet(None), _45);     // scope 12 at $DIR/address_of.rs:+32:9: +32:10
+        AscribeUserType(_45, o, UserTypeProjection { base: UserType(27), projs: [] }); // scope 12 at $DIR/address_of.rs:+32:12: +32:25
+        StorageLive(_47);                // scope 13 at $DIR/address_of.rs:+33:9: +33:10
+        StorageLive(_48);                // scope 13 at $DIR/address_of.rs:+33:25: +33:26
+        _48 = &raw mut (*_3);            // scope 13 at $DIR/address_of.rs:+33:25: +33:26
+        _47 = move _48 as *mut [i32] (Pointer(Unsize)); // scope 13 at $DIR/address_of.rs:+33:25: +33:26
+        StorageDead(_48);                // scope 13 at $DIR/address_of.rs:+33:25: +33:26
+        FakeRead(ForLet(None), _47);     // scope 13 at $DIR/address_of.rs:+33:9: +33:10
+        AscribeUserType(_47, o, UserTypeProjection { base: UserType(29), projs: [] }); // scope 13 at $DIR/address_of.rs:+33:12: +33:22
+        _0 = const ();                   // scope 0 at $DIR/address_of.rs:+0:26: +34:2
+        StorageDead(_47);                // scope 13 at $DIR/address_of.rs:+34:1: +34:2
+        StorageDead(_45);                // scope 12 at $DIR/address_of.rs:+34:1: +34:2
+        StorageDead(_44);                // scope 11 at $DIR/address_of.rs:+34:1: +34:2
+        StorageDead(_43);                // scope 10 at $DIR/address_of.rs:+34:1: +34:2
+        StorageDead(_33);                // scope 9 at $DIR/address_of.rs:+34:1: +34:2
+        StorageDead(_31);                // scope 8 at $DIR/address_of.rs:+34:1: +34:2
+        StorageDead(_30);                // scope 7 at $DIR/address_of.rs:+34:1: +34:2
+        StorageDead(_29);                // scope 6 at $DIR/address_of.rs:+34:1: +34:2
+        StorageDead(_19);                // scope 5 at $DIR/address_of.rs:+34:1: +34:2
+        StorageDead(_17);                // scope 4 at $DIR/address_of.rs:+34:1: +34:2
+        StorageDead(_16);                // scope 3 at $DIR/address_of.rs:+34:1: +34:2
+        StorageDead(_15);                // scope 2 at $DIR/address_of.rs:+34:1: +34:2
+        StorageDead(_4);                 // scope 1 at $DIR/address_of.rs:+34:1: +34:2
+        StorageDead(_3);                 // scope 1 at $DIR/address_of.rs:+34:1: +34:2
+        StorageDead(_2);                 // scope 0 at $DIR/address_of.rs:+34:1: +34:2
+        StorageDead(_1);                 // scope 0 at $DIR/address_of.rs:+34:1: +34:2
+        return;                          // scope 0 at $DIR/address_of.rs:+34:2: +34:2
     }
 }
diff --git a/src/test/mir-opt/address_of.borrow_and_cast.SimplifyCfg-initial.after.mir b/src/test/mir-opt/address_of.borrow_and_cast.SimplifyCfg-initial.after.mir
index 060077b8adb9..4c67376b56a6 100644
--- a/src/test/mir-opt/address_of.borrow_and_cast.SimplifyCfg-initial.after.mir
+++ b/src/test/mir-opt/address_of.borrow_and_cast.SimplifyCfg-initial.after.mir
@@ -1,47 +1,47 @@
 // MIR for `borrow_and_cast` after SimplifyCfg-initial
 
 fn borrow_and_cast(_1: i32) -> () {
-    debug x => _1;                       // in scope 0 at $DIR/address-of.rs:+0:20: +0:25
-    let mut _0: ();                      // return place in scope 0 at $DIR/address-of.rs:+0:32: +0:32
-    let _2: *const i32;                  // in scope 0 at $DIR/address-of.rs:+1:9: +1:10
-    let _3: &i32;                        // in scope 0 at $DIR/address-of.rs:+1:13: +1:15
-    let _5: &mut i32;                    // in scope 0 at $DIR/address-of.rs:+2:13: +2:19
-    let mut _7: &mut i32;                // in scope 0 at $DIR/address-of.rs:+3:13: +3:19
+    debug x => _1;                       // in scope 0 at $DIR/address_of.rs:+0:20: +0:25
+    let mut _0: ();                      // return place in scope 0 at $DIR/address_of.rs:+0:32: +0:32
+    let _2: *const i32;                  // in scope 0 at $DIR/address_of.rs:+1:9: +1:10
+    let _3: &i32;                        // in scope 0 at $DIR/address_of.rs:+1:13: +1:15
+    let _5: &mut i32;                    // in scope 0 at $DIR/address_of.rs:+2:13: +2:19
+    let mut _7: &mut i32;                // in scope 0 at $DIR/address_of.rs:+3:13: +3:19
     scope 1 {
-        debug p => _2;                   // in scope 1 at $DIR/address-of.rs:+1:9: +1:10
-        let _4: *const i32;              // in scope 1 at $DIR/address-of.rs:+2:9: +2:10
+        debug p => _2;                   // in scope 1 at $DIR/address_of.rs:+1:9: +1:10
+        let _4: *const i32;              // in scope 1 at $DIR/address_of.rs:+2:9: +2:10
         scope 2 {
-            debug q => _4;               // in scope 2 at $DIR/address-of.rs:+2:9: +2:10
-            let _6: *mut i32;            // in scope 2 at $DIR/address-of.rs:+3:9: +3:10
+            debug q => _4;               // in scope 2 at $DIR/address_of.rs:+2:9: +2:10
+            let _6: *mut i32;            // in scope 2 at $DIR/address_of.rs:+3:9: +3:10
             scope 3 {
-                debug r => _6;           // in scope 3 at $DIR/address-of.rs:+3:9: +3:10
+                debug r => _6;           // in scope 3 at $DIR/address_of.rs:+3:9: +3:10
             }
         }
     }
 
     bb0: {
-        StorageLive(_2);                 // scope 0 at $DIR/address-of.rs:+1:9: +1:10
-        StorageLive(_3);                 // scope 0 at $DIR/address-of.rs:+1:13: +1:15
-        _3 = &_1;                        // scope 0 at $DIR/address-of.rs:+1:13: +1:15
-        _2 = &raw const (*_3);           // scope 0 at $DIR/address-of.rs:+1:13: +1:15
-        FakeRead(ForLet(None), _2);      // scope 0 at $DIR/address-of.rs:+1:9: +1:10
-        StorageDead(_3);                 // scope 0 at $DIR/address-of.rs:+1:29: +1:30
-        StorageLive(_4);                 // scope 1 at $DIR/address-of.rs:+2:9: +2:10
-        StorageLive(_5);                 // scope 1 at $DIR/address-of.rs:+2:13: +2:19
-        _5 = &mut _1;                    // scope 1 at $DIR/address-of.rs:+2:13: +2:19
-        _4 = &raw const (*_5);           // scope 1 at $DIR/address-of.rs:+2:13: +2:19
-        FakeRead(ForLet(None), _4);      // scope 1 at $DIR/address-of.rs:+2:9: +2:10
-        StorageDead(_5);                 // scope 1 at $DIR/address-of.rs:+2:33: +2:34
-        StorageLive(_6);                 // scope 2 at $DIR/address-of.rs:+3:9: +3:10
-        StorageLive(_7);                 // scope 2 at $DIR/address-of.rs:+3:13: +3:19
-        _7 = &mut _1;                    // scope 2 at $DIR/address-of.rs:+3:13: +3:19
-        _6 = &raw mut (*_7);             // scope 2 at $DIR/address-of.rs:+3:13: +3:19
-        FakeRead(ForLet(None), _6);      // scope 2 at $DIR/address-of.rs:+3:9: +3:10
-        StorageDead(_7);                 // scope 2 at $DIR/address-of.rs:+3:31: +3:32
-        _0 = const ();                   // scope 0 at $DIR/address-of.rs:+0:32: +4:2
-        StorageDead(_6);                 // scope 2 at $DIR/address-of.rs:+4:1: +4:2
-        StorageDead(_4);                 // scope 1 at $DIR/address-of.rs:+4:1: +4:2
-        StorageDead(_2);                 // scope 0 at $DIR/address-of.rs:+4:1: +4:2
-        return;                          // scope 0 at $DIR/address-of.rs:+4:2: +4:2
+        StorageLive(_2);                 // scope 0 at $DIR/address_of.rs:+1:9: +1:10
+        StorageLive(_3);                 // scope 0 at $DIR/address_of.rs:+1:13: +1:15
+        _3 = &_1;                        // scope 0 at $DIR/address_of.rs:+1:13: +1:15
+        _2 = &raw const (*_3);           // scope 0 at $DIR/address_of.rs:+1:13: +1:15
+        FakeRead(ForLet(None), _2);      // scope 0 at $DIR/address_of.rs:+1:9: +1:10
+        StorageDead(_3);                 // scope 0 at $DIR/address_of.rs:+1:29: +1:30
+        StorageLive(_4);                 // scope 1 at $DIR/address_of.rs:+2:9: +2:10
+        StorageLive(_5);                 // scope 1 at $DIR/address_of.rs:+2:13: +2:19
+        _5 = &mut _1;                    // scope 1 at $DIR/address_of.rs:+2:13: +2:19
+        _4 = &raw const (*_5);           // scope 1 at $DIR/address_of.rs:+2:13: +2:19
+        FakeRead(ForLet(None), _4);      // scope 1 at $DIR/address_of.rs:+2:9: +2:10
+        StorageDead(_5);                 // scope 1 at $DIR/address_of.rs:+2:33: +2:34
+        StorageLive(_6);                 // scope 2 at $DIR/address_of.rs:+3:9: +3:10
+        StorageLive(_7);                 // scope 2 at $DIR/address_of.rs:+3:13: +3:19
+        _7 = &mut _1;                    // scope 2 at $DIR/address_of.rs:+3:13: +3:19
+        _6 = &raw mut (*_7);             // scope 2 at $DIR/address_of.rs:+3:13: +3:19
+        FakeRead(ForLet(None), _6);      // scope 2 at $DIR/address_of.rs:+3:9: +3:10
+        StorageDead(_7);                 // scope 2 at $DIR/address_of.rs:+3:31: +3:32
+        _0 = const ();                   // scope 0 at $DIR/address_of.rs:+0:32: +4:2
+        StorageDead(_6);                 // scope 2 at $DIR/address_of.rs:+4:1: +4:2
+        StorageDead(_4);                 // scope 1 at $DIR/address_of.rs:+4:1: +4:2
+        StorageDead(_2);                 // scope 0 at $DIR/address_of.rs:+4:1: +4:2
+        return;                          // scope 0 at $DIR/address_of.rs:+4:2: +4:2
     }
 }
diff --git a/src/test/mir-opt/address-of.rs b/src/test/mir-opt/address_of.rs
similarity index 100%
rename from src/test/mir-opt/address-of.rs
rename to src/test/mir-opt/address_of.rs
diff --git a/src/test/mir-opt/array_index_is_temporary.main.SimplifyCfg-elaborate-drops.after.mir b/src/test/mir-opt/array_index_is_temporary.main.SimplifyCfg-elaborate-drops.after.mir
index 27f883ed321a..af5178d4079d 100644
--- a/src/test/mir-opt/array_index_is_temporary.main.SimplifyCfg-elaborate-drops.after.mir
+++ b/src/test/mir-opt/array_index_is_temporary.main.SimplifyCfg-elaborate-drops.after.mir
@@ -1,22 +1,22 @@
 // MIR for `main` after SimplifyCfg-elaborate-drops
 
 fn main() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/array-index-is-temporary.rs:+0:11: +0:11
-    let mut _1: [u32; 3];                // in scope 0 at $DIR/array-index-is-temporary.rs:+1:9: +1:14
-    let mut _4: &mut usize;              // in scope 0 at $DIR/array-index-is-temporary.rs:+3:25: +3:31
-    let mut _5: u32;                     // in scope 0 at $DIR/array-index-is-temporary.rs:+4:12: +4:29
-    let mut _6: *mut usize;              // in scope 0 at $DIR/array-index-is-temporary.rs:+4:25: +4:26
-    let _7: usize;                       // in scope 0 at $DIR/array-index-is-temporary.rs:+4:7: +4:8
-    let mut _8: usize;                   // in scope 0 at $DIR/array-index-is-temporary.rs:+4:5: +4:9
-    let mut _9: bool;                    // in scope 0 at $DIR/array-index-is-temporary.rs:+4:5: +4:9
+    let mut _0: ();                      // return place in scope 0 at $DIR/array_index_is_temporary.rs:+0:11: +0:11
+    let mut _1: [u32; 3];                // in scope 0 at $DIR/array_index_is_temporary.rs:+1:9: +1:14
+    let mut _4: &mut usize;              // in scope 0 at $DIR/array_index_is_temporary.rs:+3:25: +3:31
+    let mut _5: u32;                     // in scope 0 at $DIR/array_index_is_temporary.rs:+4:12: +4:29
+    let mut _6: *mut usize;              // in scope 0 at $DIR/array_index_is_temporary.rs:+4:25: +4:26
+    let _7: usize;                       // in scope 0 at $DIR/array_index_is_temporary.rs:+4:7: +4:8
+    let mut _8: usize;                   // in scope 0 at $DIR/array_index_is_temporary.rs:+4:5: +4:9
+    let mut _9: bool;                    // in scope 0 at $DIR/array_index_is_temporary.rs:+4:5: +4:9
     scope 1 {
-        debug x => _1;                   // in scope 1 at $DIR/array-index-is-temporary.rs:+1:9: +1:14
-        let mut _2: usize;               // in scope 1 at $DIR/array-index-is-temporary.rs:+2:9: +2:14
+        debug x => _1;                   // in scope 1 at $DIR/array_index_is_temporary.rs:+1:9: +1:14
+        let mut _2: usize;               // in scope 1 at $DIR/array_index_is_temporary.rs:+2:9: +2:14
         scope 2 {
-            debug y => _2;               // in scope 2 at $DIR/array-index-is-temporary.rs:+2:9: +2:14
-            let _3: *mut usize;          // in scope 2 at $DIR/array-index-is-temporary.rs:+3:9: +3:10
+            debug y => _2;               // in scope 2 at $DIR/array_index_is_temporary.rs:+2:9: +2:14
+            let _3: *mut usize;          // in scope 2 at $DIR/array_index_is_temporary.rs:+3:9: +3:10
             scope 3 {
-                debug z => _3;           // in scope 3 at $DIR/array-index-is-temporary.rs:+3:9: +3:10
+                debug z => _3;           // in scope 3 at $DIR/array_index_is_temporary.rs:+3:9: +3:10
                 scope 4 {
                 }
             }
@@ -24,41 +24,41 @@ fn main() -> () {
     }
 
     bb0: {
-        StorageLive(_1);                 // scope 0 at $DIR/array-index-is-temporary.rs:+1:9: +1:14
-        _1 = [const 42_u32, const 43_u32, const 44_u32]; // scope 0 at $DIR/array-index-is-temporary.rs:+1:17: +1:29
-        StorageLive(_2);                 // scope 1 at $DIR/array-index-is-temporary.rs:+2:9: +2:14
-        _2 = const 1_usize;              // scope 1 at $DIR/array-index-is-temporary.rs:+2:17: +2:18
-        StorageLive(_3);                 // scope 2 at $DIR/array-index-is-temporary.rs:+3:9: +3:10
-        StorageLive(_4);                 // scope 2 at $DIR/array-index-is-temporary.rs:+3:25: +3:31
-        _4 = &mut _2;                    // scope 2 at $DIR/array-index-is-temporary.rs:+3:25: +3:31
-        _3 = &raw mut (*_4);             // scope 2 at $DIR/array-index-is-temporary.rs:+3:25: +3:31
-        StorageDead(_4);                 // scope 2 at $DIR/array-index-is-temporary.rs:+3:31: +3:32
-        StorageLive(_5);                 // scope 3 at $DIR/array-index-is-temporary.rs:+4:12: +4:29
-        StorageLive(_6);                 // scope 4 at $DIR/array-index-is-temporary.rs:+4:25: +4:26
-        _6 = _3;                         // scope 4 at $DIR/array-index-is-temporary.rs:+4:25: +4:26
-        _5 = foo(move _6) -> bb1;        // scope 4 at $DIR/array-index-is-temporary.rs:+4:21: +4:27
+        StorageLive(_1);                 // scope 0 at $DIR/array_index_is_temporary.rs:+1:9: +1:14
+        _1 = [const 42_u32, const 43_u32, const 44_u32]; // scope 0 at $DIR/array_index_is_temporary.rs:+1:17: +1:29
+        StorageLive(_2);                 // scope 1 at $DIR/array_index_is_temporary.rs:+2:9: +2:14
+        _2 = const 1_usize;              // scope 1 at $DIR/array_index_is_temporary.rs:+2:17: +2:18
+        StorageLive(_3);                 // scope 2 at $DIR/array_index_is_temporary.rs:+3:9: +3:10
+        StorageLive(_4);                 // scope 2 at $DIR/array_index_is_temporary.rs:+3:25: +3:31
+        _4 = &mut _2;                    // scope 2 at $DIR/array_index_is_temporary.rs:+3:25: +3:31
+        _3 = &raw mut (*_4);             // scope 2 at $DIR/array_index_is_temporary.rs:+3:25: +3:31
+        StorageDead(_4);                 // scope 2 at $DIR/array_index_is_temporary.rs:+3:31: +3:32
+        StorageLive(_5);                 // scope 3 at $DIR/array_index_is_temporary.rs:+4:12: +4:29
+        StorageLive(_6);                 // scope 4 at $DIR/array_index_is_temporary.rs:+4:25: +4:26
+        _6 = _3;                         // scope 4 at $DIR/array_index_is_temporary.rs:+4:25: +4:26
+        _5 = foo(move _6) -> bb1;        // scope 4 at $DIR/array_index_is_temporary.rs:+4:21: +4:27
                                          // mir::Constant
-                                         // + span: $DIR/array-index-is-temporary.rs:16:21: 16:24
+                                         // + span: $DIR/array_index_is_temporary.rs:16:21: 16:24
                                          // + literal: Const { ty: unsafe fn(*mut usize) -> u32 {foo}, val: Value(<ZST>) }
     }
 
     bb1: {
-        StorageDead(_6);                 // scope 4 at $DIR/array-index-is-temporary.rs:+4:26: +4:27
-        StorageLive(_7);                 // scope 3 at $DIR/array-index-is-temporary.rs:+4:7: +4:8
-        _7 = _2;                         // scope 3 at $DIR/array-index-is-temporary.rs:+4:7: +4:8
-        _8 = Len(_1);                    // scope 3 at $DIR/array-index-is-temporary.rs:+4:5: +4:9
-        _9 = Lt(_7, _8);                 // scope 3 at $DIR/array-index-is-temporary.rs:+4:5: +4:9
-        assert(move _9, "index out of bounds: the length is {} but the index is {}", move _8, _7) -> bb2; // scope 3 at $DIR/array-index-is-temporary.rs:+4:5: +4:9
+        StorageDead(_6);                 // scope 4 at $DIR/array_index_is_temporary.rs:+4:26: +4:27
+        StorageLive(_7);                 // scope 3 at $DIR/array_index_is_temporary.rs:+4:7: +4:8
+        _7 = _2;                         // scope 3 at $DIR/array_index_is_temporary.rs:+4:7: +4:8
+        _8 = Len(_1);                    // scope 3 at $DIR/array_index_is_temporary.rs:+4:5: +4:9
+        _9 = Lt(_7, _8);                 // scope 3 at $DIR/array_index_is_temporary.rs:+4:5: +4:9
+        assert(move _9, "index out of bounds: the length is {} but the index is {}", move _8, _7) -> bb2; // scope 3 at $DIR/array_index_is_temporary.rs:+4:5: +4:9
     }
 
     bb2: {
-        _1[_7] = move _5;                // scope 3 at $DIR/array-index-is-temporary.rs:+4:5: +4:29
-        StorageDead(_5);                 // scope 3 at $DIR/array-index-is-temporary.rs:+4:28: +4:29
-        StorageDead(_7);                 // scope 3 at $DIR/array-index-is-temporary.rs:+4:29: +4:30
-        _0 = const ();                   // scope 0 at $DIR/array-index-is-temporary.rs:+0:11: +5:2
-        StorageDead(_3);                 // scope 2 at $DIR/array-index-is-temporary.rs:+5:1: +5:2
-        StorageDead(_2);                 // scope 1 at $DIR/array-index-is-temporary.rs:+5:1: +5:2
-        StorageDead(_1);                 // scope 0 at $DIR/array-index-is-temporary.rs:+5:1: +5:2
-        return;                          // scope 0 at $DIR/array-index-is-temporary.rs:+5:2: +5:2
+        _1[_7] = move _5;                // scope 3 at $DIR/array_index_is_temporary.rs:+4:5: +4:29
+        StorageDead(_5);                 // scope 3 at $DIR/array_index_is_temporary.rs:+4:28: +4:29
+        StorageDead(_7);                 // scope 3 at $DIR/array_index_is_temporary.rs:+4:29: +4:30
+        _0 = const ();                   // scope 0 at $DIR/array_index_is_temporary.rs:+0:11: +5:2
+        StorageDead(_3);                 // scope 2 at $DIR/array_index_is_temporary.rs:+5:1: +5:2
+        StorageDead(_2);                 // scope 1 at $DIR/array_index_is_temporary.rs:+5:1: +5:2
+        StorageDead(_1);                 // scope 0 at $DIR/array_index_is_temporary.rs:+5:1: +5:2
+        return;                          // scope 0 at $DIR/array_index_is_temporary.rs:+5:2: +5:2
     }
 }
diff --git a/src/test/mir-opt/array-index-is-temporary.rs b/src/test/mir-opt/array_index_is_temporary.rs
similarity index 100%
rename from src/test/mir-opt/array-index-is-temporary.rs
rename to src/test/mir-opt/array_index_is_temporary.rs
diff --git a/src/test/mir-opt/building/custom/references.immut_ref.built.after.mir b/src/test/mir-opt/building/custom/references.immut_ref.built.after.mir
new file mode 100644
index 000000000000..4a5ddde4081e
--- /dev/null
+++ b/src/test/mir-opt/building/custom/references.immut_ref.built.after.mir
@@ -0,0 +1,14 @@
+// MIR for `immut_ref` after built
+
+fn immut_ref(_1: &i32) -> &i32 {
+    let mut _0: &i32;                    // return place in scope 0 at $DIR/references.rs:+0:30: +0:34
+    let mut _2: *const i32;              // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+
+    bb0: {
+        _2 = &raw const (*_1);           // scope 0 at $DIR/references.rs:+0:1: +0:34
+        Retag([raw] _2);                 // scope 0 at $DIR/references.rs:+0:1: +0:34
+        _0 = &(*_2);                     // scope 0 at $DIR/references.rs:+0:1: +0:34
+        Retag(_0);                       // scope 0 at $DIR/references.rs:+0:1: +0:34
+        return;                          // scope 0 at $DIR/references.rs:+0:1: +0:34
+    }
+}
diff --git a/src/test/mir-opt/building/custom/references.mut_ref.built.after.mir b/src/test/mir-opt/building/custom/references.mut_ref.built.after.mir
new file mode 100644
index 000000000000..ec8509f69d14
--- /dev/null
+++ b/src/test/mir-opt/building/custom/references.mut_ref.built.after.mir
@@ -0,0 +1,14 @@
+// MIR for `mut_ref` after built
+
+fn mut_ref(_1: &mut i32) -> &mut i32 {
+    let mut _0: &mut i32;                // return place in scope 0 at $DIR/references.rs:+0:32: +0:40
+    let mut _2: *mut i32;                // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+
+    bb0: {
+        _2 = &raw mut (*_1);             // scope 0 at $DIR/references.rs:+0:1: +0:40
+        Retag([raw] _2);                 // scope 0 at $DIR/references.rs:+0:1: +0:40
+        _0 = &mut (*_2);                 // scope 0 at $DIR/references.rs:+0:1: +0:40
+        Retag(_0);                       // scope 0 at $DIR/references.rs:+0:1: +0:40
+        return;                          // scope 0 at $DIR/references.rs:+0:1: +0:40
+    }
+}
diff --git a/src/test/mir-opt/building/custom/references.rs b/src/test/mir-opt/building/custom/references.rs
new file mode 100644
index 000000000000..dee85722e865
--- /dev/null
+++ b/src/test/mir-opt/building/custom/references.rs
@@ -0,0 +1,43 @@
+#![feature(custom_mir, core_intrinsics)]
+
+extern crate core;
+use core::intrinsics::mir::*;
+use core::ptr::{addr_of, addr_of_mut};
+
+// EMIT_MIR references.mut_ref.built.after.mir
+#[custom_mir(dialect = "runtime", phase = "optimized")]
+pub fn mut_ref(x: &mut i32) -> &mut i32 {
+    mir!(
+        let t: *mut i32;
+
+        {
+            t = addr_of_mut!(*x);
+            RetagRaw(t);
+            RET = &mut *t;
+            Retag(RET);
+            Return()
+        }
+    )
+}
+
+// EMIT_MIR references.immut_ref.built.after.mir
+#[custom_mir(dialect = "runtime", phase = "optimized")]
+pub fn immut_ref(x: &i32) -> &i32 {
+    mir!(
+        let t: *const i32;
+
+        {
+            t = addr_of!(*x);
+            RetagRaw(t);
+            RET = & *t;
+            Retag(RET);
+            Return()
+        }
+    )
+}
+
+fn main() {
+    let mut x = 5;
+    assert_eq!(*mut_ref(&mut x), 5);
+    assert_eq!(*immut_ref(&x), 5);
+}
diff --git a/src/test/mir-opt/building/custom/simple_assign.rs b/src/test/mir-opt/building/custom/simple_assign.rs
new file mode 100644
index 000000000000..ec6dbe1d0526
--- /dev/null
+++ b/src/test/mir-opt/building/custom/simple_assign.rs
@@ -0,0 +1,37 @@
+#![feature(custom_mir, core_intrinsics)]
+
+extern crate core;
+use core::intrinsics::mir::*;
+
+// EMIT_MIR simple_assign.simple.built.after.mir
+#[custom_mir(dialect = "built")]
+pub fn simple(x: i32) -> i32 {
+    mir!(
+        let temp1: i32;
+        let temp2: _;
+
+        {
+            temp1 = x;
+            Goto(exit)
+        }
+
+        exit = {
+            temp2 = Move(temp1);
+            RET = temp2;
+            Return()
+        }
+    )
+}
+
+// EMIT_MIR simple_assign.simple_ref.built.after.mir
+#[custom_mir(dialect = "built")]
+pub fn simple_ref(x: &mut i32) -> &mut i32 {
+    mir!({
+        RET = Move(x);
+        Return()
+    })
+}
+
+fn main() {
+    assert_eq!(5, simple(5));
+}
diff --git a/src/test/mir-opt/building/custom/simple_assign.simple.built.after.mir b/src/test/mir-opt/building/custom/simple_assign.simple.built.after.mir
new file mode 100644
index 000000000000..a5a2834c2e1b
--- /dev/null
+++ b/src/test/mir-opt/building/custom/simple_assign.simple.built.after.mir
@@ -0,0 +1,18 @@
+// MIR for `simple` after built
+
+fn simple(_1: i32) -> i32 {
+    let mut _0: i32;                     // return place in scope 0 at $DIR/simple_assign.rs:+0:26: +0:29
+    let mut _2: i32;                     // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+    let mut _3: i32;                     // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+
+    bb0: {
+        _2 = _1;                         // scope 0 at $DIR/simple_assign.rs:+0:1: +0:29
+        goto -> bb1;                     // scope 0 at $DIR/simple_assign.rs:+0:1: +0:29
+    }
+
+    bb1: {
+        _3 = move _2;                    // scope 0 at $DIR/simple_assign.rs:+0:1: +0:29
+        _0 = _3;                         // scope 0 at $DIR/simple_assign.rs:+0:1: +0:29
+        return;                          // scope 0 at $DIR/simple_assign.rs:+0:1: +0:29
+    }
+}
diff --git a/src/test/mir-opt/building/custom/simple_assign.simple_ref.built.after.mir b/src/test/mir-opt/building/custom/simple_assign.simple_ref.built.after.mir
new file mode 100644
index 000000000000..6c90f0130a2e
--- /dev/null
+++ b/src/test/mir-opt/building/custom/simple_assign.simple_ref.built.after.mir
@@ -0,0 +1,10 @@
+// MIR for `simple_ref` after built
+
+fn simple_ref(_1: &mut i32) -> &mut i32 {
+    let mut _0: &mut i32;                // return place in scope 0 at $DIR/simple_assign.rs:+0:35: +0:43
+
+    bb0: {
+        _0 = move _1;                    // scope 0 at $DIR/simple_assign.rs:+0:1: +0:43
+        return;                          // scope 0 at $DIR/simple_assign.rs:+0:1: +0:43
+    }
+}
diff --git a/src/test/mir-opt/enum_cast.bar.mir_map.0.mir b/src/test/mir-opt/building/enum_cast.bar.built.after.mir
similarity index 62%
rename from src/test/mir-opt/enum_cast.bar.mir_map.0.mir
rename to src/test/mir-opt/building/enum_cast.bar.built.after.mir
index e58085f701ac..0746e0b498e9 100644
--- a/src/test/mir-opt/enum_cast.bar.mir_map.0.mir
+++ b/src/test/mir-opt/building/enum_cast.bar.built.after.mir
@@ -1,15 +1,21 @@
-// MIR for `bar` 0 mir_map
+// MIR for `bar` after built
 
 fn bar(_1: Bar) -> usize {
     debug bar => _1;                     // in scope 0 at $DIR/enum_cast.rs:+0:8: +0:11
     let mut _0: usize;                   // return place in scope 0 at $DIR/enum_cast.rs:+0:21: +0:26
     let _2: Bar;                         // in scope 0 at $DIR/enum_cast.rs:+1:5: +1:8
     let mut _3: isize;                   // in scope 0 at $DIR/enum_cast.rs:+1:5: +1:8
+    let mut _4: bool;                    // in scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
+    let mut _5: bool;                    // in scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
 
     bb0: {
         StorageLive(_2);                 // scope 0 at $DIR/enum_cast.rs:+1:5: +1:8
         _2 = move _1;                    // scope 0 at $DIR/enum_cast.rs:+1:5: +1:8
         _3 = discriminant(_2);           // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
+        _4 = Ge(const 1_isize, _3);      // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
+        assume(_4);                      // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
+        _5 = Le(const 0_isize, _3);      // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
+        assume(_5);                      // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
         _0 = move _3 as usize (IntToInt); // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
         StorageDead(_2);                 // scope 0 at $DIR/enum_cast.rs:+1:16: +1:17
         return;                          // scope 0 at $DIR/enum_cast.rs:+2:2: +2:2
diff --git a/src/test/mir-opt/enum_cast.boo.mir_map.0.mir b/src/test/mir-opt/building/enum_cast.boo.built.after.mir
similarity index 62%
rename from src/test/mir-opt/enum_cast.boo.mir_map.0.mir
rename to src/test/mir-opt/building/enum_cast.boo.built.after.mir
index 525c6234ed31..699c876b01ac 100644
--- a/src/test/mir-opt/enum_cast.boo.mir_map.0.mir
+++ b/src/test/mir-opt/building/enum_cast.boo.built.after.mir
@@ -1,15 +1,21 @@
-// MIR for `boo` 0 mir_map
+// MIR for `boo` after built
 
 fn boo(_1: Boo) -> usize {
     debug boo => _1;                     // in scope 0 at $DIR/enum_cast.rs:+0:8: +0:11
     let mut _0: usize;                   // return place in scope 0 at $DIR/enum_cast.rs:+0:21: +0:26
     let _2: Boo;                         // in scope 0 at $DIR/enum_cast.rs:+1:5: +1:8
     let mut _3: u8;                      // in scope 0 at $DIR/enum_cast.rs:+1:5: +1:8
+    let mut _4: bool;                    // in scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
+    let mut _5: bool;                    // in scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
 
     bb0: {
         StorageLive(_2);                 // scope 0 at $DIR/enum_cast.rs:+1:5: +1:8
         _2 = move _1;                    // scope 0 at $DIR/enum_cast.rs:+1:5: +1:8
         _3 = discriminant(_2);           // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
+        _4 = Ge(const 1_u8, _3);         // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
+        assume(_4);                      // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
+        _5 = Le(const 0_u8, _3);         // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
+        assume(_5);                      // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
         _0 = move _3 as usize (IntToInt); // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
         StorageDead(_2);                 // scope 0 at $DIR/enum_cast.rs:+1:16: +1:17
         return;                          // scope 0 at $DIR/enum_cast.rs:+2:2: +2:2
diff --git a/src/test/mir-opt/enum_cast.droppy.mir_map.0.mir b/src/test/mir-opt/building/enum_cast.droppy.built.after.mir
similarity index 74%
rename from src/test/mir-opt/enum_cast.droppy.mir_map.0.mir
rename to src/test/mir-opt/building/enum_cast.droppy.built.after.mir
index bb5faa48047a..5231c2eab957 100644
--- a/src/test/mir-opt/enum_cast.droppy.mir_map.0.mir
+++ b/src/test/mir-opt/building/enum_cast.droppy.built.after.mir
@@ -1,4 +1,4 @@
-// MIR for `droppy` 0 mir_map
+// MIR for `droppy` after built
 
 fn droppy() -> () {
     let mut _0: ();                      // return place in scope 0 at $DIR/enum_cast.rs:+0:13: +0:13
@@ -6,7 +6,9 @@ fn droppy() -> () {
     let _2: Droppy;                      // in scope 0 at $DIR/enum_cast.rs:+2:13: +2:14
     let _4: Droppy;                      // in scope 0 at $DIR/enum_cast.rs:+5:17: +5:18
     let mut _5: isize;                   // in scope 0 at $DIR/enum_cast.rs:+5:17: +5:18
-    let _6: Droppy;                      // in scope 0 at $DIR/enum_cast.rs:+7:9: +7:10
+    let mut _6: bool;                    // in scope 0 at $DIR/enum_cast.rs:+5:17: +5:27
+    let mut _7: bool;                    // in scope 0 at $DIR/enum_cast.rs:+5:17: +5:27
+    let _8: Droppy;                      // in scope 0 at $DIR/enum_cast.rs:+7:9: +7:10
     scope 1 {
         debug x => _2;                   // in scope 1 at $DIR/enum_cast.rs:+2:13: +2:14
         scope 2 {
@@ -17,7 +19,7 @@ fn droppy() -> () {
         }
     }
     scope 4 {
-        debug z => _6;                   // in scope 4 at $DIR/enum_cast.rs:+7:9: +7:10
+        debug z => _8;                   // in scope 4 at $DIR/enum_cast.rs:+7:9: +7:10
     }
 
     bb0: {
@@ -29,6 +31,10 @@ fn droppy() -> () {
         StorageLive(_4);                 // scope 3 at $DIR/enum_cast.rs:+5:17: +5:18
         _4 = move _2;                    // scope 3 at $DIR/enum_cast.rs:+5:17: +5:18
         _5 = discriminant(_4);           // scope 3 at $DIR/enum_cast.rs:+5:17: +5:27
+        _6 = Ge(const 2_isize, _5);      // scope 3 at $DIR/enum_cast.rs:+5:17: +5:27
+        assume(_6);                      // scope 3 at $DIR/enum_cast.rs:+5:17: +5:27
+        _7 = Le(const 0_isize, _5);      // scope 3 at $DIR/enum_cast.rs:+5:17: +5:27
+        assume(_7);                      // scope 3 at $DIR/enum_cast.rs:+5:17: +5:27
         _3 = move _5 as usize (IntToInt); // scope 3 at $DIR/enum_cast.rs:+5:17: +5:27
         drop(_4) -> [return: bb1, unwind: bb4]; // scope 3 at $DIR/enum_cast.rs:+5:26: +5:27
     }
@@ -44,15 +50,15 @@ fn droppy() -> () {
     bb2: {
         StorageDead(_2);                 // scope 0 at $DIR/enum_cast.rs:+6:5: +6:6
         StorageDead(_1);                 // scope 0 at $DIR/enum_cast.rs:+6:5: +6:6
-        StorageLive(_6);                 // scope 0 at $DIR/enum_cast.rs:+7:9: +7:10
-        _6 = Droppy::B;                  // scope 0 at $DIR/enum_cast.rs:+7:13: +7:22
-        FakeRead(ForLet(None), _6);      // scope 0 at $DIR/enum_cast.rs:+7:9: +7:10
+        StorageLive(_8);                 // scope 0 at $DIR/enum_cast.rs:+7:9: +7:10
+        _8 = Droppy::B;                  // scope 0 at $DIR/enum_cast.rs:+7:13: +7:22
+        FakeRead(ForLet(None), _8);      // scope 0 at $DIR/enum_cast.rs:+7:9: +7:10
         _0 = const ();                   // scope 0 at $DIR/enum_cast.rs:+0:13: +8:2
-        drop(_6) -> [return: bb3, unwind: bb5]; // scope 0 at $DIR/enum_cast.rs:+8:1: +8:2
+        drop(_8) -> [return: bb3, unwind: bb5]; // scope 0 at $DIR/enum_cast.rs:+8:1: +8:2
     }
 
     bb3: {
-        StorageDead(_6);                 // scope 0 at $DIR/enum_cast.rs:+8:1: +8:2
+        StorageDead(_8);                 // scope 0 at $DIR/enum_cast.rs:+8:1: +8:2
         return;                          // scope 0 at $DIR/enum_cast.rs:+8:2: +8:2
     }
 
diff --git a/src/test/mir-opt/enum_cast.foo.mir_map.0.mir b/src/test/mir-opt/building/enum_cast.foo.built.after.mir
similarity index 96%
rename from src/test/mir-opt/enum_cast.foo.mir_map.0.mir
rename to src/test/mir-opt/building/enum_cast.foo.built.after.mir
index a1d29a0b9032..17e0abf2e319 100644
--- a/src/test/mir-opt/enum_cast.foo.mir_map.0.mir
+++ b/src/test/mir-opt/building/enum_cast.foo.built.after.mir
@@ -1,4 +1,4 @@
-// MIR for `foo` 0 mir_map
+// MIR for `foo` after built
 
 fn foo(_1: Foo) -> usize {
     debug foo => _1;                     // in scope 0 at $DIR/enum_cast.rs:+0:8: +0:11
diff --git a/src/test/mir-opt/enum_cast.rs b/src/test/mir-opt/building/enum_cast.rs
similarity index 76%
rename from src/test/mir-opt/enum_cast.rs
rename to src/test/mir-opt/building/enum_cast.rs
index 090142aaf355..98fd5acfb14f 100644
--- a/src/test/mir-opt/enum_cast.rs
+++ b/src/test/mir-opt/building/enum_cast.rs
@@ -1,6 +1,6 @@
-// EMIT_MIR enum_cast.foo.mir_map.0.mir
-// EMIT_MIR enum_cast.bar.mir_map.0.mir
-// EMIT_MIR enum_cast.boo.mir_map.0.mir
+// EMIT_MIR enum_cast.foo.built.after.mir
+// EMIT_MIR enum_cast.bar.built.after.mir
+// EMIT_MIR enum_cast.boo.built.after.mir
 
 enum Foo {
     A
@@ -27,7 +27,7 @@ fn boo(boo: Boo) -> usize {
     boo as usize
 }
 
-// EMIT_MIR enum_cast.droppy.mir_map.0.mir
+// EMIT_MIR enum_cast.droppy.built.after.mir
 enum Droppy {
     A, B, C
 }
diff --git a/src/test/mir-opt/issue_101867.main.mir_map.0.mir b/src/test/mir-opt/building/issue_101867.main.built.after.mir
similarity index 77%
rename from src/test/mir-opt/issue_101867.main.mir_map.0.mir
rename to src/test/mir-opt/building/issue_101867.main.built.after.mir
index 42a9e5587603..0ebd840cf2d5 100644
--- a/src/test/mir-opt/issue_101867.main.mir_map.0.mir
+++ b/src/test/mir-opt/building/issue_101867.main.built.after.mir
@@ -1,33 +1,33 @@
-// MIR for `main` 0 mir_map
+// MIR for `main` after built
 
 | User Type Annotations
-| 0: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(std::option::Option<u8>) }, span: $DIR/issue-101867.rs:3:12: 3:22, inferred_ty: std::option::Option<u8>
-| 1: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(std::option::Option<u8>) }, span: $DIR/issue-101867.rs:3:12: 3:22, inferred_ty: std::option::Option<u8>
+| 0: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(std::option::Option<u8>) }, span: $DIR/issue_101867.rs:3:12: 3:22, inferred_ty: std::option::Option<u8>
+| 1: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(std::option::Option<u8>) }, span: $DIR/issue_101867.rs:3:12: 3:22, inferred_ty: std::option::Option<u8>
 |
 fn main() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/issue-101867.rs:+0:11: +0:11
-    let _1: std::option::Option<u8> as UserTypeProjection { base: UserType(0), projs: [] }; // in scope 0 at $DIR/issue-101867.rs:+1:9: +1:10
-    let mut _2: !;                       // in scope 0 at $DIR/issue-101867.rs:+2:26: +4:6
+    let mut _0: ();                      // return place in scope 0 at $DIR/issue_101867.rs:+0:11: +0:11
+    let _1: std::option::Option<u8> as UserTypeProjection { base: UserType(0), projs: [] }; // in scope 0 at $DIR/issue_101867.rs:+1:9: +1:10
+    let mut _2: !;                       // in scope 0 at $DIR/issue_101867.rs:+2:26: +4:6
     let _3: ();                          // in scope 0 at $SRC_DIR/std/src/panic.rs:LL:COL
     let mut _4: !;                       // in scope 0 at $SRC_DIR/std/src/panic.rs:LL:COL
-    let mut _6: isize;                   // in scope 0 at $DIR/issue-101867.rs:+2:9: +2:16
+    let mut _6: isize;                   // in scope 0 at $DIR/issue_101867.rs:+2:9: +2:16
     scope 1 {
-        debug x => _1;                   // in scope 1 at $DIR/issue-101867.rs:+1:9: +1:10
-        let _5: u8;                      // in scope 1 at $DIR/issue-101867.rs:+2:14: +2:15
+        debug x => _1;                   // in scope 1 at $DIR/issue_101867.rs:+1:9: +1:10
+        let _5: u8;                      // in scope 1 at $DIR/issue_101867.rs:+2:14: +2:15
         scope 2 {
-            debug y => _5;               // in scope 2 at $DIR/issue-101867.rs:+2:14: +2:15
+            debug y => _5;               // in scope 2 at $DIR/issue_101867.rs:+2:14: +2:15
         }
     }
 
     bb0: {
-        StorageLive(_1);                 // scope 0 at $DIR/issue-101867.rs:+1:9: +1:10
-        _1 = Option::<u8>::Some(const 1_u8); // scope 0 at $DIR/issue-101867.rs:+1:25: +1:32
-        FakeRead(ForLet(None), _1);      // scope 0 at $DIR/issue-101867.rs:+1:9: +1:10
-        AscribeUserType(_1, o, UserTypeProjection { base: UserType(1), projs: [] }); // scope 0 at $DIR/issue-101867.rs:+1:12: +1:22
-        StorageLive(_5);                 // scope 1 at $DIR/issue-101867.rs:+2:14: +2:15
-        FakeRead(ForMatchedPlace(None), _1); // scope 1 at $DIR/issue-101867.rs:+2:19: +2:20
-        _6 = discriminant(_1);           // scope 1 at $DIR/issue-101867.rs:+2:19: +2:20
-        switchInt(move _6) -> [1_isize: bb4, otherwise: bb3]; // scope 1 at $DIR/issue-101867.rs:+2:9: +2:16
+        StorageLive(_1);                 // scope 0 at $DIR/issue_101867.rs:+1:9: +1:10
+        _1 = Option::<u8>::Some(const 1_u8); // scope 0 at $DIR/issue_101867.rs:+1:25: +1:32
+        FakeRead(ForLet(None), _1);      // scope 0 at $DIR/issue_101867.rs:+1:9: +1:10
+        AscribeUserType(_1, o, UserTypeProjection { base: UserType(1), projs: [] }); // scope 0 at $DIR/issue_101867.rs:+1:12: +1:22
+        StorageLive(_5);                 // scope 1 at $DIR/issue_101867.rs:+2:14: +2:15
+        FakeRead(ForMatchedPlace(None), _1); // scope 1 at $DIR/issue_101867.rs:+2:19: +2:20
+        _6 = discriminant(_1);           // scope 1 at $DIR/issue_101867.rs:+2:19: +2:20
+        switchInt(move _6) -> [1_isize: bb4, otherwise: bb3]; // scope 1 at $DIR/issue_101867.rs:+2:9: +2:16
     }
 
     bb1: {
@@ -44,32 +44,32 @@ fn main() -> () {
 
     bb2: {
         StorageDead(_4);                 // scope 1 at $SRC_DIR/std/src/panic.rs:LL:COL
-        StorageDead(_3);                 // scope 1 at $DIR/issue-101867.rs:+3:16: +3:17
-        unreachable;                     // scope 1 at $DIR/issue-101867.rs:+2:26: +4:6
+        StorageDead(_3);                 // scope 1 at $DIR/issue_101867.rs:+3:16: +3:17
+        unreachable;                     // scope 1 at $DIR/issue_101867.rs:+2:26: +4:6
     }
 
     bb3: {
-        goto -> bb6;                     // scope 1 at $DIR/issue-101867.rs:+2:19: +2:20
+        goto -> bb6;                     // scope 1 at $DIR/issue_101867.rs:+2:19: +2:20
     }
 
     bb4: {
-        falseEdge -> [real: bb5, imaginary: bb3]; // scope 1 at $DIR/issue-101867.rs:+2:9: +2:16
+        falseEdge -> [real: bb5, imaginary: bb3]; // scope 1 at $DIR/issue_101867.rs:+2:9: +2:16
     }
 
     bb5: {
-        _5 = ((_1 as Some).0: u8);       // scope 1 at $DIR/issue-101867.rs:+2:14: +2:15
-        _0 = const ();                   // scope 0 at $DIR/issue-101867.rs:+0:11: +5:2
-        StorageDead(_5);                 // scope 1 at $DIR/issue-101867.rs:+5:1: +5:2
-        StorageDead(_1);                 // scope 0 at $DIR/issue-101867.rs:+5:1: +5:2
-        return;                          // scope 0 at $DIR/issue-101867.rs:+5:2: +5:2
+        _5 = ((_1 as Some).0: u8);       // scope 1 at $DIR/issue_101867.rs:+2:14: +2:15
+        _0 = const ();                   // scope 0 at $DIR/issue_101867.rs:+0:11: +5:2
+        StorageDead(_5);                 // scope 1 at $DIR/issue_101867.rs:+5:1: +5:2
+        StorageDead(_1);                 // scope 0 at $DIR/issue_101867.rs:+5:1: +5:2
+        return;                          // scope 0 at $DIR/issue_101867.rs:+5:2: +5:2
     }
 
     bb6: {
-        StorageDead(_5);                 // scope 1 at $DIR/issue-101867.rs:+5:1: +5:2
-        goto -> bb1;                     // scope 0 at $DIR/issue-101867.rs:+0:11: +5:2
+        StorageDead(_5);                 // scope 1 at $DIR/issue_101867.rs:+5:1: +5:2
+        goto -> bb1;                     // scope 0 at $DIR/issue_101867.rs:+0:11: +5:2
     }
 
     bb7 (cleanup): {
-        resume;                          // scope 0 at $DIR/issue-101867.rs:+0:1: +5:2
+        resume;                          // scope 0 at $DIR/issue_101867.rs:+0:1: +5:2
     }
 }
diff --git a/src/test/mir-opt/issue-101867.rs b/src/test/mir-opt/building/issue_101867.rs
similarity index 68%
rename from src/test/mir-opt/issue-101867.rs
rename to src/test/mir-opt/building/issue_101867.rs
index 8a357eb79951..a32d8cb37142 100644
--- a/src/test/mir-opt/issue-101867.rs
+++ b/src/test/mir-opt/building/issue_101867.rs
@@ -1,4 +1,4 @@
-// EMIT_MIR issue_101867.main.mir_map.0.mir
+// EMIT_MIR issue_101867.main.built.after.mir
 fn main() {
     let x: Option<u8> = Some(1);
     let Some(y) = x else {
diff --git a/src/test/mir-opt/issue_49232.main.mir_map.0.mir b/src/test/mir-opt/building/issue_49232.main.built.after.mir
similarity index 72%
rename from src/test/mir-opt/issue_49232.main.mir_map.0.mir
rename to src/test/mir-opt/building/issue_49232.main.built.after.mir
index 821323b5e242..9182bcaa21fa 100644
--- a/src/test/mir-opt/issue_49232.main.mir_map.0.mir
+++ b/src/test/mir-opt/building/issue_49232.main.built.after.mir
@@ -1,82 +1,82 @@
-// MIR for `main` 0 mir_map
+// MIR for `main` after built
 
 fn main() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/issue-49232.rs:+0:11: +0:11
-    let mut _1: ();                      // in scope 0 at $DIR/issue-49232.rs:+0:1: +10:2
-    let _2: i32;                         // in scope 0 at $DIR/issue-49232.rs:+2:13: +2:19
-    let mut _3: bool;                    // in scope 0 at $DIR/issue-49232.rs:+3:19: +3:23
-    let mut _4: !;                       // in scope 0 at $DIR/issue-49232.rs:+5:25: +5:30
-    let _5: ();                          // in scope 0 at $DIR/issue-49232.rs:+8:9: +8:22
-    let mut _6: &i32;                    // in scope 0 at $DIR/issue-49232.rs:+8:14: +8:21
+    let mut _0: ();                      // return place in scope 0 at $DIR/issue_49232.rs:+0:11: +0:11
+    let mut _1: ();                      // in scope 0 at $DIR/issue_49232.rs:+0:1: +10:2
+    let _2: i32;                         // in scope 0 at $DIR/issue_49232.rs:+2:13: +2:19
+    let mut _3: bool;                    // in scope 0 at $DIR/issue_49232.rs:+3:19: +3:23
+    let mut _4: !;                       // in scope 0 at $DIR/issue_49232.rs:+5:25: +5:30
+    let _5: ();                          // in scope 0 at $DIR/issue_49232.rs:+8:9: +8:22
+    let mut _6: &i32;                    // in scope 0 at $DIR/issue_49232.rs:+8:14: +8:21
     scope 1 {
-        debug beacon => _2;              // in scope 1 at $DIR/issue-49232.rs:+2:13: +2:19
+        debug beacon => _2;              // in scope 1 at $DIR/issue_49232.rs:+2:13: +2:19
     }
 
     bb0: {
-        goto -> bb1;                     // scope 0 at $DIR/issue-49232.rs:+1:5: +9:6
+        goto -> bb1;                     // scope 0 at $DIR/issue_49232.rs:+1:5: +9:6
     }
 
     bb1: {
-        falseUnwind -> [real: bb2, cleanup: bb11]; // scope 0 at $DIR/issue-49232.rs:+1:5: +9:6
+        falseUnwind -> [real: bb2, cleanup: bb11]; // scope 0 at $DIR/issue_49232.rs:+1:5: +9:6
     }
 
     bb2: {
-        StorageLive(_2);                 // scope 0 at $DIR/issue-49232.rs:+2:13: +2:19
-        StorageLive(_3);                 // scope 0 at $DIR/issue-49232.rs:+3:19: +3:23
-        _3 = const true;                 // scope 0 at $DIR/issue-49232.rs:+3:19: +3:23
-        FakeRead(ForMatchedPlace(None), _3); // scope 0 at $DIR/issue-49232.rs:+3:19: +3:23
-        switchInt(_3) -> [false: bb3, otherwise: bb4]; // scope 0 at $DIR/issue-49232.rs:+3:13: +3:23
+        StorageLive(_2);                 // scope 0 at $DIR/issue_49232.rs:+2:13: +2:19
+        StorageLive(_3);                 // scope 0 at $DIR/issue_49232.rs:+3:19: +3:23
+        _3 = const true;                 // scope 0 at $DIR/issue_49232.rs:+3:19: +3:23
+        FakeRead(ForMatchedPlace(None), _3); // scope 0 at $DIR/issue_49232.rs:+3:19: +3:23
+        switchInt(_3) -> [false: bb3, otherwise: bb4]; // scope 0 at $DIR/issue_49232.rs:+3:13: +3:23
     }
 
     bb3: {
-        falseEdge -> [real: bb5, imaginary: bb4]; // scope 0 at $DIR/issue-49232.rs:+4:17: +4:22
+        falseEdge -> [real: bb5, imaginary: bb4]; // scope 0 at $DIR/issue_49232.rs:+4:17: +4:22
     }
 
     bb4: {
-        _0 = const ();                   // scope 0 at $DIR/issue-49232.rs:+5:25: +5:30
-        goto -> bb10;                    // scope 0 at $DIR/issue-49232.rs:+5:25: +5:30
+        _0 = const ();                   // scope 0 at $DIR/issue_49232.rs:+5:25: +5:30
+        goto -> bb10;                    // scope 0 at $DIR/issue_49232.rs:+5:25: +5:30
     }
 
     bb5: {
-        _2 = const 4_i32;                // scope 0 at $DIR/issue-49232.rs:+4:26: +4:27
-        goto -> bb8;                     // scope 0 at $DIR/issue-49232.rs:+4:26: +4:27
+        _2 = const 4_i32;                // scope 0 at $DIR/issue_49232.rs:+4:26: +4:27
+        goto -> bb8;                     // scope 0 at $DIR/issue_49232.rs:+4:26: +4:27
     }
 
     bb6: {
-        unreachable;                     // scope 0 at $DIR/issue-49232.rs:+5:25: +5:30
+        unreachable;                     // scope 0 at $DIR/issue_49232.rs:+5:25: +5:30
     }
 
     bb7: {
-        goto -> bb8;                     // scope 0 at $DIR/issue-49232.rs:+6:13: +6:14
+        goto -> bb8;                     // scope 0 at $DIR/issue_49232.rs:+6:13: +6:14
     }
 
     bb8: {
-        FakeRead(ForLet(None), _2);      // scope 0 at $DIR/issue-49232.rs:+2:13: +2:19
-        StorageDead(_3);                 // scope 0 at $DIR/issue-49232.rs:+7:10: +7:11
-        StorageLive(_5);                 // scope 1 at $DIR/issue-49232.rs:+8:9: +8:22
-        StorageLive(_6);                 // scope 1 at $DIR/issue-49232.rs:+8:14: +8:21
-        _6 = &_2;                        // scope 1 at $DIR/issue-49232.rs:+8:14: +8:21
-        _5 = std::mem::drop::<&i32>(move _6) -> [return: bb9, unwind: bb11]; // scope 1 at $DIR/issue-49232.rs:+8:9: +8:22
+        FakeRead(ForLet(None), _2);      // scope 0 at $DIR/issue_49232.rs:+2:13: +2:19
+        StorageDead(_3);                 // scope 0 at $DIR/issue_49232.rs:+7:10: +7:11
+        StorageLive(_5);                 // scope 1 at $DIR/issue_49232.rs:+8:9: +8:22
+        StorageLive(_6);                 // scope 1 at $DIR/issue_49232.rs:+8:14: +8:21
+        _6 = &_2;                        // scope 1 at $DIR/issue_49232.rs:+8:14: +8:21
+        _5 = std::mem::drop::<&i32>(move _6) -> [return: bb9, unwind: bb11]; // scope 1 at $DIR/issue_49232.rs:+8:9: +8:22
                                          // mir::Constant
-                                         // + span: $DIR/issue-49232.rs:13:9: 13:13
+                                         // + span: $DIR/issue_49232.rs:13:9: 13:13
                                          // + literal: Const { ty: fn(&i32) {std::mem::drop::<&i32>}, val: Value(<ZST>) }
     }
 
     bb9: {
-        StorageDead(_6);                 // scope 1 at $DIR/issue-49232.rs:+8:21: +8:22
-        StorageDead(_5);                 // scope 1 at $DIR/issue-49232.rs:+8:22: +8:23
-        _1 = const ();                   // scope 0 at $DIR/issue-49232.rs:+1:10: +9:6
-        StorageDead(_2);                 // scope 0 at $DIR/issue-49232.rs:+9:5: +9:6
-        goto -> bb1;                     // scope 0 at $DIR/issue-49232.rs:+1:5: +9:6
+        StorageDead(_6);                 // scope 1 at $DIR/issue_49232.rs:+8:21: +8:22
+        StorageDead(_5);                 // scope 1 at $DIR/issue_49232.rs:+8:22: +8:23
+        _1 = const ();                   // scope 0 at $DIR/issue_49232.rs:+1:10: +9:6
+        StorageDead(_2);                 // scope 0 at $DIR/issue_49232.rs:+9:5: +9:6
+        goto -> bb1;                     // scope 0 at $DIR/issue_49232.rs:+1:5: +9:6
     }
 
     bb10: {
-        StorageDead(_3);                 // scope 0 at $DIR/issue-49232.rs:+7:10: +7:11
-        StorageDead(_2);                 // scope 0 at $DIR/issue-49232.rs:+9:5: +9:6
-        return;                          // scope 0 at $DIR/issue-49232.rs:+10:2: +10:2
+        StorageDead(_3);                 // scope 0 at $DIR/issue_49232.rs:+7:10: +7:11
+        StorageDead(_2);                 // scope 0 at $DIR/issue_49232.rs:+9:5: +9:6
+        return;                          // scope 0 at $DIR/issue_49232.rs:+10:2: +10:2
     }
 
     bb11 (cleanup): {
-        resume;                          // scope 0 at $DIR/issue-49232.rs:+0:1: +10:2
+        resume;                          // scope 0 at $DIR/issue_49232.rs:+0:1: +10:2
     }
 }
diff --git a/src/test/mir-opt/issue-49232.rs b/src/test/mir-opt/building/issue_49232.rs
similarity index 86%
rename from src/test/mir-opt/issue-49232.rs
rename to src/test/mir-opt/building/issue_49232.rs
index 86494c76aec5..7e9f0de81f74 100644
--- a/src/test/mir-opt/issue-49232.rs
+++ b/src/test/mir-opt/building/issue_49232.rs
@@ -1,7 +1,7 @@
 // We must mark a variable whose initialization fails due to an
 // abort statement as StorageDead.
 
-// EMIT_MIR issue_49232.main.mir_map.0.mir
+// EMIT_MIR issue_49232.main.built.after.mir
 fn main() {
     loop {
         let beacon = {
diff --git a/src/test/mir-opt/match_false_edges.full_tested_match.PromoteTemps.after.mir b/src/test/mir-opt/building/match_false_edges.full_tested_match.built.after.mir
similarity index 85%
rename from src/test/mir-opt/match_false_edges.full_tested_match.PromoteTemps.after.mir
rename to src/test/mir-opt/building/match_false_edges.full_tested_match.built.after.mir
index b193a8d76fcb..9a190c3d60ea 100644
--- a/src/test/mir-opt/match_false_edges.full_tested_match.PromoteTemps.after.mir
+++ b/src/test/mir-opt/building/match_false_edges.full_tested_match.built.after.mir
@@ -1,4 +1,4 @@
-// MIR for `full_tested_match` after PromoteTemps
+// MIR for `full_tested_match` after built
 
 fn full_tested_match() -> () {
     let mut _0: ();                      // return place in scope 0 at $DIR/match_false_edges.rs:+0:28: +0:28
@@ -12,7 +12,6 @@ fn full_tested_match() -> () {
     let mut _8: i32;                     // in scope 0 at $DIR/match_false_edges.rs:+2:35: +2:36
     let _9: i32;                         // in scope 0 at $DIR/match_false_edges.rs:+3:14: +3:15
     let mut _10: i32;                    // in scope 0 at $DIR/match_false_edges.rs:+3:24: +3:25
-    let mut _11: &std::option::Option<i32>; // in scope 0 at $DIR/match_false_edges.rs:+2:14: +2:15
     scope 1 {
     }
     scope 2 {
@@ -34,7 +33,7 @@ fn full_tested_match() -> () {
 
     bb1: {
         _1 = (const 3_i32, const 3_i32); // scope 0 at $DIR/match_false_edges.rs:+4:17: +4:23
-        goto -> bb10;                    // scope 0 at $DIR/match_false_edges.rs:+4:17: +4:23
+        goto -> bb11;                    // scope 0 at $DIR/match_false_edges.rs:+4:17: +4:23
     }
 
     bb2: {
@@ -42,7 +41,7 @@ fn full_tested_match() -> () {
     }
 
     bb3: {
-        falseEdge -> [real: bb9, imaginary: bb1]; // scope 0 at $DIR/match_false_edges.rs:+3:9: +3:16
+        falseEdge -> [real: bb10, imaginary: bb1]; // scope 0 at $DIR/match_false_edges.rs:+3:9: +3:16
     }
 
     bb4: {
@@ -51,14 +50,10 @@ fn full_tested_match() -> () {
 
     bb5: {
         StorageLive(_6);                 // scope 0 at $DIR/match_false_edges.rs:+2:14: +2:15
-        _11 = const _;                   // scope 0 at $DIR/match_false_edges.rs:+2:14: +2:15
-                                         // mir::Constant
-                                         // + span: $DIR/match_false_edges.rs:14:14: 14:15
-                                         // + literal: Const { ty: &Option<i32>, val: Unevaluated(full_tested_match, [], Some(promoted[0])) }
-        _6 = &(((*_11) as Some).0: i32); // scope 0 at $DIR/match_false_edges.rs:+2:14: +2:15
+        _6 = &((_2 as Some).0: i32);     // scope 0 at $DIR/match_false_edges.rs:+2:14: +2:15
         _4 = &shallow _2;                // scope 0 at $DIR/match_false_edges.rs:+1:19: +1:27
         StorageLive(_7);                 // scope 0 at $DIR/match_false_edges.rs:+2:20: +2:27
-        _7 = guard() -> [return: bb6, unwind: bb11]; // scope 0 at $DIR/match_false_edges.rs:+2:20: +2:27
+        _7 = guard() -> [return: bb6, unwind: bb12]; // scope 0 at $DIR/match_false_edges.rs:+2:20: +2:27
                                          // mir::Constant
                                          // + span: $DIR/match_false_edges.rs:14:20: 14:25
                                          // + literal: Const { ty: fn() -> bool {guard}, val: Value(<ZST>) }
@@ -80,16 +75,20 @@ fn full_tested_match() -> () {
         StorageDead(_8);                 // scope 2 at $DIR/match_false_edges.rs:+2:36: +2:37
         StorageDead(_5);                 // scope 0 at $DIR/match_false_edges.rs:+2:36: +2:37
         StorageDead(_6);                 // scope 0 at $DIR/match_false_edges.rs:+2:36: +2:37
-        goto -> bb10;                    // scope 0 at $DIR/match_false_edges.rs:+2:36: +2:37
+        goto -> bb11;                    // scope 0 at $DIR/match_false_edges.rs:+2:36: +2:37
     }
 
     bb8: {
+        goto -> bb9;                     // scope 0 at $DIR/match_false_edges.rs:+2:20: +2:27
+    }
+
+    bb9: {
         StorageDead(_7);                 // scope 0 at $DIR/match_false_edges.rs:+2:26: +2:27
         StorageDead(_6);                 // scope 0 at $DIR/match_false_edges.rs:+2:36: +2:37
         goto -> bb3;                     // scope 0 at $DIR/match_false_edges.rs:+2:20: +2:27
     }
 
-    bb9: {
+    bb10: {
         StorageLive(_9);                 // scope 0 at $DIR/match_false_edges.rs:+3:14: +3:15
         _9 = ((_2 as Some).0: i32);      // scope 0 at $DIR/match_false_edges.rs:+3:14: +3:15
         StorageLive(_10);                // scope 3 at $DIR/match_false_edges.rs:+3:24: +3:25
@@ -97,17 +96,17 @@ fn full_tested_match() -> () {
         _1 = (const 2_i32, move _10);    // scope 3 at $DIR/match_false_edges.rs:+3:20: +3:26
         StorageDead(_10);                // scope 3 at $DIR/match_false_edges.rs:+3:25: +3:26
         StorageDead(_9);                 // scope 0 at $DIR/match_false_edges.rs:+3:25: +3:26
-        goto -> bb10;                    // scope 0 at $DIR/match_false_edges.rs:+3:25: +3:26
+        goto -> bb11;                    // scope 0 at $DIR/match_false_edges.rs:+3:25: +3:26
     }
 
-    bb10: {
+    bb11: {
         StorageDead(_2);                 // scope 0 at $DIR/match_false_edges.rs:+5:6: +5:7
         StorageDead(_1);                 // scope 0 at $DIR/match_false_edges.rs:+5:6: +5:7
         _0 = const ();                   // scope 0 at $DIR/match_false_edges.rs:+0:28: +6:2
         return;                          // scope 0 at $DIR/match_false_edges.rs:+6:2: +6:2
     }
 
-    bb11 (cleanup): {
+    bb12 (cleanup): {
         resume;                          // scope 0 at $DIR/match_false_edges.rs:+0:1: +6:2
     }
 }
diff --git a/src/test/mir-opt/match_false_edges.full_tested_match2.PromoteTemps.before.mir b/src/test/mir-opt/building/match_false_edges.full_tested_match2.built.after.mir
similarity index 91%
rename from src/test/mir-opt/match_false_edges.full_tested_match2.PromoteTemps.before.mir
rename to src/test/mir-opt/building/match_false_edges.full_tested_match2.built.after.mir
index 145ed878fc9e..1c9953e7efc1 100644
--- a/src/test/mir-opt/match_false_edges.full_tested_match2.PromoteTemps.before.mir
+++ b/src/test/mir-opt/building/match_false_edges.full_tested_match2.built.after.mir
@@ -1,4 +1,4 @@
-// MIR for `full_tested_match2` before PromoteTemps
+// MIR for `full_tested_match2` after built
 
 fn full_tested_match2() -> () {
     let mut _0: ();                      // return place in scope 0 at $DIR/match_false_edges.rs:+0:29: +0:29
@@ -32,7 +32,7 @@ fn full_tested_match2() -> () {
     }
 
     bb1: {
-        falseEdge -> [real: bb9, imaginary: bb3]; // scope 0 at $DIR/match_false_edges.rs:+3:9: +3:13
+        falseEdge -> [real: bb10, imaginary: bb3]; // scope 0 at $DIR/match_false_edges.rs:+3:9: +3:13
     }
 
     bb2: {
@@ -47,7 +47,7 @@ fn full_tested_match2() -> () {
         _1 = (const 2_i32, move _10);    // scope 3 at $DIR/match_false_edges.rs:+4:20: +4:26
         StorageDead(_10);                // scope 3 at $DIR/match_false_edges.rs:+4:25: +4:26
         StorageDead(_9);                 // scope 0 at $DIR/match_false_edges.rs:+4:25: +4:26
-        goto -> bb10;                    // scope 0 at $DIR/match_false_edges.rs:+4:25: +4:26
+        goto -> bb11;                    // scope 0 at $DIR/match_false_edges.rs:+4:25: +4:26
     }
 
     bb4: {
@@ -59,7 +59,7 @@ fn full_tested_match2() -> () {
         _6 = &((_2 as Some).0: i32);     // scope 0 at $DIR/match_false_edges.rs:+2:14: +2:15
         _4 = &shallow _2;                // scope 0 at $DIR/match_false_edges.rs:+1:19: +1:27
         StorageLive(_7);                 // scope 0 at $DIR/match_false_edges.rs:+2:20: +2:27
-        _7 = guard() -> [return: bb6, unwind: bb11]; // scope 0 at $DIR/match_false_edges.rs:+2:20: +2:27
+        _7 = guard() -> [return: bb6, unwind: bb12]; // scope 0 at $DIR/match_false_edges.rs:+2:20: +2:27
                                          // mir::Constant
                                          // + span: $DIR/match_false_edges.rs:25:20: 25:25
                                          // + literal: Const { ty: fn() -> bool {guard}, val: Value(<ZST>) }
@@ -81,28 +81,32 @@ fn full_tested_match2() -> () {
         StorageDead(_8);                 // scope 2 at $DIR/match_false_edges.rs:+2:36: +2:37
         StorageDead(_5);                 // scope 0 at $DIR/match_false_edges.rs:+2:36: +2:37
         StorageDead(_6);                 // scope 0 at $DIR/match_false_edges.rs:+2:36: +2:37
-        goto -> bb10;                    // scope 0 at $DIR/match_false_edges.rs:+2:36: +2:37
+        goto -> bb11;                    // scope 0 at $DIR/match_false_edges.rs:+2:36: +2:37
     }
 
     bb8: {
+        goto -> bb9;                     // scope 0 at $DIR/match_false_edges.rs:+2:20: +2:27
+    }
+
+    bb9: {
         StorageDead(_7);                 // scope 0 at $DIR/match_false_edges.rs:+2:26: +2:27
         StorageDead(_6);                 // scope 0 at $DIR/match_false_edges.rs:+2:36: +2:37
         falseEdge -> [real: bb3, imaginary: bb1]; // scope 0 at $DIR/match_false_edges.rs:+2:20: +2:27
     }
 
-    bb9: {
+    bb10: {
         _1 = (const 3_i32, const 3_i32); // scope 0 at $DIR/match_false_edges.rs:+3:17: +3:23
-        goto -> bb10;                    // scope 0 at $DIR/match_false_edges.rs:+3:17: +3:23
+        goto -> bb11;                    // scope 0 at $DIR/match_false_edges.rs:+3:17: +3:23
     }
 
-    bb10: {
+    bb11: {
         StorageDead(_2);                 // scope 0 at $DIR/match_false_edges.rs:+5:6: +5:7
         StorageDead(_1);                 // scope 0 at $DIR/match_false_edges.rs:+5:6: +5:7
         _0 = const ();                   // scope 0 at $DIR/match_false_edges.rs:+0:29: +6:2
         return;                          // scope 0 at $DIR/match_false_edges.rs:+6:2: +6:2
     }
 
-    bb11 (cleanup): {
+    bb12 (cleanup): {
         resume;                          // scope 0 at $DIR/match_false_edges.rs:+0:1: +6:2
     }
 }
diff --git a/src/test/mir-opt/match_false_edges.main.PromoteTemps.before.mir b/src/test/mir-opt/building/match_false_edges.main.built.after.mir
similarity index 83%
rename from src/test/mir-opt/match_false_edges.main.PromoteTemps.before.mir
rename to src/test/mir-opt/building/match_false_edges.main.built.after.mir
index 8f40e8a887f2..08c67d39d780 100644
--- a/src/test/mir-opt/match_false_edges.main.PromoteTemps.before.mir
+++ b/src/test/mir-opt/building/match_false_edges.main.built.after.mir
@@ -1,4 +1,4 @@
-// MIR for `main` before PromoteTemps
+// MIR for `main` after built
 
 fn main() -> () {
     let mut _0: ();                      // return place in scope 0 at $DIR/match_false_edges.rs:+0:11: +0:11
@@ -43,41 +43,54 @@ fn main() -> () {
     }
 
     bb1: {
-        falseEdge -> [real: bb9, imaginary: bb4]; // scope 0 at $DIR/match_false_edges.rs:+3:9: +3:11
+        falseEdge -> [real: bb13, imaginary: bb6]; // scope 0 at $DIR/match_false_edges.rs:+3:9: +3:11
     }
 
     bb2: {
-        falseEdge -> [real: bb5, imaginary: bb1]; // scope 0 at $DIR/match_false_edges.rs:+2:9: +2:17
+        falseEdge -> [real: bb8, imaginary: bb1]; // scope 0 at $DIR/match_false_edges.rs:+2:9: +2:17
     }
 
     bb3: {
+        goto -> bb1;                     // scope 0 at $DIR/match_false_edges.rs:+1:13: +1:26
+    }
+
+    bb4: {
+        _3 = discriminant(_2);           // scope 0 at $DIR/match_false_edges.rs:+1:19: +1:26
+        switchInt(move _3) -> [1_isize: bb6, otherwise: bb5]; // scope 0 at $DIR/match_false_edges.rs:+1:13: +1:26
+    }
+
+    bb5: {
         StorageLive(_14);                // scope 0 at $DIR/match_false_edges.rs:+5:9: +5:11
         _14 = _2;                        // scope 0 at $DIR/match_false_edges.rs:+5:9: +5:11
         _1 = const 4_i32;                // scope 5 at $DIR/match_false_edges.rs:+5:15: +5:16
         StorageDead(_14);                // scope 0 at $DIR/match_false_edges.rs:+5:15: +5:16
-        goto -> bb14;                    // scope 0 at $DIR/match_false_edges.rs:+5:15: +5:16
+        goto -> bb19;                    // scope 0 at $DIR/match_false_edges.rs:+5:15: +5:16
     }
 
-    bb4: {
-        falseEdge -> [real: bb10, imaginary: bb3]; // scope 0 at $DIR/match_false_edges.rs:+4:9: +4:16
+    bb6: {
+        falseEdge -> [real: bb14, imaginary: bb5]; // scope 0 at $DIR/match_false_edges.rs:+4:9: +4:16
     }
 
-    bb5: {
+    bb7: {
+        goto -> bb5;                     // scope 0 at $DIR/match_false_edges.rs:+1:13: +1:26
+    }
+
+    bb8: {
         StorageLive(_7);                 // scope 0 at $DIR/match_false_edges.rs:+2:14: +2:16
         _7 = &((_2 as Some).0: i32);     // scope 0 at $DIR/match_false_edges.rs:+2:14: +2:16
         _5 = &shallow _2;                // scope 0 at $DIR/match_false_edges.rs:+1:19: +1:26
         StorageLive(_8);                 // scope 0 at $DIR/match_false_edges.rs:+2:21: +2:28
-        _8 = guard() -> [return: bb6, unwind: bb15]; // scope 0 at $DIR/match_false_edges.rs:+2:21: +2:28
+        _8 = guard() -> [return: bb9, unwind: bb20]; // scope 0 at $DIR/match_false_edges.rs:+2:21: +2:28
                                          // mir::Constant
                                          // + span: $DIR/match_false_edges.rs:34:21: 34:26
                                          // + literal: Const { ty: fn() -> bool {guard}, val: Value(<ZST>) }
     }
 
-    bb6: {
-        switchInt(move _8) -> [false: bb8, otherwise: bb7]; // scope 0 at $DIR/match_false_edges.rs:+2:21: +2:28
+    bb9: {
+        switchInt(move _8) -> [false: bb11, otherwise: bb10]; // scope 0 at $DIR/match_false_edges.rs:+2:21: +2:28
     }
 
-    bb7: {
+    bb10: {
         StorageDead(_8);                 // scope 0 at $DIR/match_false_edges.rs:+2:27: +2:28
         FakeRead(ForMatchGuard, _5);     // scope 0 at $DIR/match_false_edges.rs:+2:27: +2:28
         FakeRead(ForGuardBinding, _7);   // scope 0 at $DIR/match_false_edges.rs:+2:27: +2:28
@@ -86,41 +99,45 @@ fn main() -> () {
         _1 = const 1_i32;                // scope 2 at $DIR/match_false_edges.rs:+2:32: +2:33
         StorageDead(_6);                 // scope 0 at $DIR/match_false_edges.rs:+2:32: +2:33
         StorageDead(_7);                 // scope 0 at $DIR/match_false_edges.rs:+2:32: +2:33
-        goto -> bb14;                    // scope 0 at $DIR/match_false_edges.rs:+2:32: +2:33
+        goto -> bb19;                    // scope 0 at $DIR/match_false_edges.rs:+2:32: +2:33
     }
 
-    bb8: {
+    bb11: {
+        goto -> bb12;                    // scope 0 at $DIR/match_false_edges.rs:+2:21: +2:28
+    }
+
+    bb12: {
         StorageDead(_8);                 // scope 0 at $DIR/match_false_edges.rs:+2:27: +2:28
         StorageDead(_7);                 // scope 0 at $DIR/match_false_edges.rs:+2:32: +2:33
-        falseEdge -> [real: bb1, imaginary: bb1]; // scope 0 at $DIR/match_false_edges.rs:+2:21: +2:28
+        falseEdge -> [real: bb3, imaginary: bb1]; // scope 0 at $DIR/match_false_edges.rs:+2:21: +2:28
     }
 
-    bb9: {
+    bb13: {
         StorageLive(_9);                 // scope 0 at $DIR/match_false_edges.rs:+3:9: +3:11
         _9 = _2;                         // scope 0 at $DIR/match_false_edges.rs:+3:9: +3:11
         _1 = const 2_i32;                // scope 3 at $DIR/match_false_edges.rs:+3:15: +3:16
         StorageDead(_9);                 // scope 0 at $DIR/match_false_edges.rs:+3:15: +3:16
-        goto -> bb14;                    // scope 0 at $DIR/match_false_edges.rs:+3:15: +3:16
+        goto -> bb19;                    // scope 0 at $DIR/match_false_edges.rs:+3:15: +3:16
     }
 
-    bb10: {
+    bb14: {
         StorageLive(_11);                // scope 0 at $DIR/match_false_edges.rs:+4:14: +4:15
         _11 = &((_2 as Some).0: i32);    // scope 0 at $DIR/match_false_edges.rs:+4:14: +4:15
         _5 = &shallow _2;                // scope 0 at $DIR/match_false_edges.rs:+1:19: +1:26
         StorageLive(_12);                // scope 0 at $DIR/match_false_edges.rs:+4:20: +4:29
         StorageLive(_13);                // scope 0 at $DIR/match_false_edges.rs:+4:27: +4:28
         _13 = (*_11);                    // scope 0 at $DIR/match_false_edges.rs:+4:27: +4:28
-        _12 = guard2(move _13) -> [return: bb11, unwind: bb15]; // scope 0 at $DIR/match_false_edges.rs:+4:20: +4:29
+        _12 = guard2(move _13) -> [return: bb15, unwind: bb20]; // scope 0 at $DIR/match_false_edges.rs:+4:20: +4:29
                                          // mir::Constant
                                          // + span: $DIR/match_false_edges.rs:36:20: 36:26
                                          // + literal: Const { ty: fn(i32) -> bool {guard2}, val: Value(<ZST>) }
     }
 
-    bb11: {
-        switchInt(move _12) -> [false: bb13, otherwise: bb12]; // scope 0 at $DIR/match_false_edges.rs:+4:20: +4:29
+    bb15: {
+        switchInt(move _12) -> [false: bb17, otherwise: bb16]; // scope 0 at $DIR/match_false_edges.rs:+4:20: +4:29
     }
 
-    bb12: {
+    bb16: {
         StorageDead(_13);                // scope 0 at $DIR/match_false_edges.rs:+4:28: +4:29
         StorageDead(_12);                // scope 0 at $DIR/match_false_edges.rs:+4:28: +4:29
         FakeRead(ForMatchGuard, _5);     // scope 0 at $DIR/match_false_edges.rs:+4:28: +4:29
@@ -130,24 +147,28 @@ fn main() -> () {
         _1 = const 3_i32;                // scope 4 at $DIR/match_false_edges.rs:+4:33: +4:34
         StorageDead(_10);                // scope 0 at $DIR/match_false_edges.rs:+4:33: +4:34
         StorageDead(_11);                // scope 0 at $DIR/match_false_edges.rs:+4:33: +4:34
-        goto -> bb14;                    // scope 0 at $DIR/match_false_edges.rs:+4:33: +4:34
+        goto -> bb19;                    // scope 0 at $DIR/match_false_edges.rs:+4:33: +4:34
     }
 
-    bb13: {
+    bb17: {
+        goto -> bb18;                    // scope 0 at $DIR/match_false_edges.rs:+4:20: +4:29
+    }
+
+    bb18: {
         StorageDead(_13);                // scope 0 at $DIR/match_false_edges.rs:+4:28: +4:29
         StorageDead(_12);                // scope 0 at $DIR/match_false_edges.rs:+4:28: +4:29
         StorageDead(_11);                // scope 0 at $DIR/match_false_edges.rs:+4:33: +4:34
-        falseEdge -> [real: bb3, imaginary: bb3]; // scope 0 at $DIR/match_false_edges.rs:+4:20: +4:29
+        falseEdge -> [real: bb7, imaginary: bb5]; // scope 0 at $DIR/match_false_edges.rs:+4:20: +4:29
     }
 
-    bb14: {
+    bb19: {
         StorageDead(_2);                 // scope 0 at $DIR/match_false_edges.rs:+6:6: +6:7
         StorageDead(_1);                 // scope 0 at $DIR/match_false_edges.rs:+6:6: +6:7
         _0 = const ();                   // scope 0 at $DIR/match_false_edges.rs:+0:11: +7:2
         return;                          // scope 0 at $DIR/match_false_edges.rs:+7:2: +7:2
     }
 
-    bb15 (cleanup): {
+    bb20 (cleanup): {
         resume;                          // scope 0 at $DIR/match_false_edges.rs:+0:1: +7:2
     }
 }
diff --git a/src/test/mir-opt/match_false_edges.rs b/src/test/mir-opt/building/match_false_edges.rs
similarity index 77%
rename from src/test/mir-opt/match_false_edges.rs
rename to src/test/mir-opt/building/match_false_edges.rs
index 3603253dafcc..ddfcc1493191 100644
--- a/src/test/mir-opt/match_false_edges.rs
+++ b/src/test/mir-opt/building/match_false_edges.rs
@@ -8,7 +8,7 @@ fn guard2(_: i32) -> bool {
 
 // no_mangle to make sure this gets instantiated even in an executable.
 #[no_mangle]
-// EMIT_MIR match_false_edges.full_tested_match.PromoteTemps.after.mir
+// EMIT_MIR match_false_edges.full_tested_match.built.after.mir
 pub fn full_tested_match() {
     let _ = match Some(42) {
         Some(x) if guard() => (1, x),
@@ -19,7 +19,7 @@ pub fn full_tested_match() {
 
 // no_mangle to make sure this gets instantiated even in an executable.
 #[no_mangle]
-// EMIT_MIR match_false_edges.full_tested_match2.PromoteTemps.before.mir
+// EMIT_MIR match_false_edges.full_tested_match2.built.after.mir
 pub fn full_tested_match2() {
     let _ = match Some(42) {
         Some(x) if guard() => (1, x),
@@ -28,7 +28,7 @@ pub fn full_tested_match2() {
     };
 }
 
-// EMIT_MIR match_false_edges.main.PromoteTemps.before.mir
+// EMIT_MIR match_false_edges.main.built.after.mir
 fn main() {
     let _ = match Some(1) {
         Some(_w) if guard() => 1,
diff --git a/src/test/mir-opt/receiver_ptr_mutability.main.mir_map.0.mir b/src/test/mir-opt/building/receiver_ptr_mutability.main.built.after.mir
similarity index 66%
rename from src/test/mir-opt/receiver_ptr_mutability.main.mir_map.0.mir
rename to src/test/mir-opt/building/receiver_ptr_mutability.main.built.after.mir
index 45797ec0607c..41eb00363bd9 100644
--- a/src/test/mir-opt/receiver_ptr_mutability.main.mir_map.0.mir
+++ b/src/test/mir-opt/building/receiver_ptr_mutability.main.built.after.mir
@@ -1,96 +1,96 @@
-// MIR for `main` 0 mir_map
+// MIR for `main` after built
 
 | User Type Annotations
-| 0: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*mut Test) }, span: $DIR/receiver-ptr-mutability.rs:14:14: 14:23, inferred_ty: *mut Test
-| 1: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*mut Test) }, span: $DIR/receiver-ptr-mutability.rs:14:14: 14:23, inferred_ty: *mut Test
-| 2: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }, CanonicalVarInfo { kind: Region(U0) }, CanonicalVarInfo { kind: Region(U0) }, CanonicalVarInfo { kind: Region(U0) }], value: Ty(&&&&*mut Test) }, span: $DIR/receiver-ptr-mutability.rs:18:18: 18:31, inferred_ty: &&&&*mut Test
-| 3: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }, CanonicalVarInfo { kind: Region(U0) }, CanonicalVarInfo { kind: Region(U0) }, CanonicalVarInfo { kind: Region(U0) }], value: Ty(&&&&*mut Test) }, span: $DIR/receiver-ptr-mutability.rs:18:18: 18:31, inferred_ty: &&&&*mut Test
+| 0: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*mut Test) }, span: $DIR/receiver_ptr_mutability.rs:14:14: 14:23, inferred_ty: *mut Test
+| 1: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(*mut Test) }, span: $DIR/receiver_ptr_mutability.rs:14:14: 14:23, inferred_ty: *mut Test
+| 2: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }, CanonicalVarInfo { kind: Region(U0) }, CanonicalVarInfo { kind: Region(U0) }, CanonicalVarInfo { kind: Region(U0) }], value: Ty(&&&&*mut Test) }, span: $DIR/receiver_ptr_mutability.rs:18:18: 18:31, inferred_ty: &&&&*mut Test
+| 3: user_ty: Canonical { max_universe: U0, variables: [CanonicalVarInfo { kind: Region(U0) }, CanonicalVarInfo { kind: Region(U0) }, CanonicalVarInfo { kind: Region(U0) }, CanonicalVarInfo { kind: Region(U0) }], value: Ty(&&&&*mut Test) }, span: $DIR/receiver_ptr_mutability.rs:18:18: 18:31, inferred_ty: &&&&*mut Test
 |
 fn main() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/receiver-ptr-mutability.rs:+0:11: +0:11
-    let _1: *mut Test as UserTypeProjection { base: UserType(0), projs: [] }; // in scope 0 at $DIR/receiver-ptr-mutability.rs:+1:9: +1:12
-    let _2: ();                          // in scope 0 at $DIR/receiver-ptr-mutability.rs:+2:5: +2:12
-    let mut _3: *const Test;             // in scope 0 at $DIR/receiver-ptr-mutability.rs:+2:5: +2:12
-    let mut _4: *mut Test;               // in scope 0 at $DIR/receiver-ptr-mutability.rs:+2:5: +2:8
-    let _6: &&&&*mut Test;               // in scope 0 at $DIR/receiver-ptr-mutability.rs:+5:34: +5:41
-    let _7: &&&*mut Test;                // in scope 0 at $DIR/receiver-ptr-mutability.rs:+5:35: +5:41
-    let _8: &&*mut Test;                 // in scope 0 at $DIR/receiver-ptr-mutability.rs:+5:36: +5:41
-    let _9: &*mut Test;                  // in scope 0 at $DIR/receiver-ptr-mutability.rs:+5:37: +5:41
-    let _10: ();                         // in scope 0 at $DIR/receiver-ptr-mutability.rs:+6:5: +6:16
-    let mut _11: *const Test;            // in scope 0 at $DIR/receiver-ptr-mutability.rs:+6:5: +6:16
-    let mut _12: *mut Test;              // in scope 0 at $DIR/receiver-ptr-mutability.rs:+6:5: +6:16
+    let mut _0: ();                      // return place in scope 0 at $DIR/receiver_ptr_mutability.rs:+0:11: +0:11
+    let _1: *mut Test as UserTypeProjection { base: UserType(0), projs: [] }; // in scope 0 at $DIR/receiver_ptr_mutability.rs:+1:9: +1:12
+    let _2: ();                          // in scope 0 at $DIR/receiver_ptr_mutability.rs:+2:5: +2:12
+    let mut _3: *const Test;             // in scope 0 at $DIR/receiver_ptr_mutability.rs:+2:5: +2:12
+    let mut _4: *mut Test;               // in scope 0 at $DIR/receiver_ptr_mutability.rs:+2:5: +2:8
+    let _6: &&&&*mut Test;               // in scope 0 at $DIR/receiver_ptr_mutability.rs:+5:34: +5:41
+    let _7: &&&*mut Test;                // in scope 0 at $DIR/receiver_ptr_mutability.rs:+5:35: +5:41
+    let _8: &&*mut Test;                 // in scope 0 at $DIR/receiver_ptr_mutability.rs:+5:36: +5:41
+    let _9: &*mut Test;                  // in scope 0 at $DIR/receiver_ptr_mutability.rs:+5:37: +5:41
+    let _10: ();                         // in scope 0 at $DIR/receiver_ptr_mutability.rs:+6:5: +6:16
+    let mut _11: *const Test;            // in scope 0 at $DIR/receiver_ptr_mutability.rs:+6:5: +6:16
+    let mut _12: *mut Test;              // in scope 0 at $DIR/receiver_ptr_mutability.rs:+6:5: +6:16
     scope 1 {
-        debug ptr => _1;                 // in scope 1 at $DIR/receiver-ptr-mutability.rs:+1:9: +1:12
-        let _5: &&&&*mut Test as UserTypeProjection { base: UserType(2), projs: [] }; // in scope 1 at $DIR/receiver-ptr-mutability.rs:+5:9: +5:16
+        debug ptr => _1;                 // in scope 1 at $DIR/receiver_ptr_mutability.rs:+1:9: +1:12
+        let _5: &&&&*mut Test as UserTypeProjection { base: UserType(2), projs: [] }; // in scope 1 at $DIR/receiver_ptr_mutability.rs:+5:9: +5:16
         scope 2 {
-            debug ptr_ref => _5;         // in scope 2 at $DIR/receiver-ptr-mutability.rs:+5:9: +5:16
+            debug ptr_ref => _5;         // in scope 2 at $DIR/receiver_ptr_mutability.rs:+5:9: +5:16
         }
     }
 
     bb0: {
-        StorageLive(_1);                 // scope 0 at $DIR/receiver-ptr-mutability.rs:+1:9: +1:12
-        _1 = null_mut::<Test>() -> [return: bb1, unwind: bb4]; // scope 0 at $DIR/receiver-ptr-mutability.rs:+1:26: +1:46
+        StorageLive(_1);                 // scope 0 at $DIR/receiver_ptr_mutability.rs:+1:9: +1:12
+        _1 = null_mut::<Test>() -> [return: bb1, unwind: bb4]; // scope 0 at $DIR/receiver_ptr_mutability.rs:+1:26: +1:46
                                          // mir::Constant
-                                         // + span: $DIR/receiver-ptr-mutability.rs:14:26: 14:44
+                                         // + span: $DIR/receiver_ptr_mutability.rs:14:26: 14:44
                                          // + literal: Const { ty: fn() -> *mut Test {null_mut::<Test>}, val: Value(<ZST>) }
     }
 
     bb1: {
-        FakeRead(ForLet(None), _1);      // scope 0 at $DIR/receiver-ptr-mutability.rs:+1:9: +1:12
-        AscribeUserType(_1, o, UserTypeProjection { base: UserType(1), projs: [] }); // scope 0 at $DIR/receiver-ptr-mutability.rs:+1:14: +1:23
-        StorageLive(_2);                 // scope 1 at $DIR/receiver-ptr-mutability.rs:+2:5: +2:12
-        StorageLive(_3);                 // scope 1 at $DIR/receiver-ptr-mutability.rs:+2:5: +2:12
-        StorageLive(_4);                 // scope 1 at $DIR/receiver-ptr-mutability.rs:+2:5: +2:8
-        _4 = _1;                         // scope 1 at $DIR/receiver-ptr-mutability.rs:+2:5: +2:8
-        _3 = move _4 as *const Test (Pointer(MutToConstPointer)); // scope 1 at $DIR/receiver-ptr-mutability.rs:+2:5: +2:12
-        StorageDead(_4);                 // scope 1 at $DIR/receiver-ptr-mutability.rs:+2:7: +2:8
-        _2 = Test::x(move _3) -> [return: bb2, unwind: bb4]; // scope 1 at $DIR/receiver-ptr-mutability.rs:+2:5: +2:12
+        FakeRead(ForLet(None), _1);      // scope 0 at $DIR/receiver_ptr_mutability.rs:+1:9: +1:12
+        AscribeUserType(_1, o, UserTypeProjection { base: UserType(1), projs: [] }); // scope 0 at $DIR/receiver_ptr_mutability.rs:+1:14: +1:23
+        StorageLive(_2);                 // scope 1 at $DIR/receiver_ptr_mutability.rs:+2:5: +2:12
+        StorageLive(_3);                 // scope 1 at $DIR/receiver_ptr_mutability.rs:+2:5: +2:12
+        StorageLive(_4);                 // scope 1 at $DIR/receiver_ptr_mutability.rs:+2:5: +2:8
+        _4 = _1;                         // scope 1 at $DIR/receiver_ptr_mutability.rs:+2:5: +2:8
+        _3 = move _4 as *const Test (Pointer(MutToConstPointer)); // scope 1 at $DIR/receiver_ptr_mutability.rs:+2:5: +2:12
+        StorageDead(_4);                 // scope 1 at $DIR/receiver_ptr_mutability.rs:+2:7: +2:8
+        _2 = Test::x(move _3) -> [return: bb2, unwind: bb4]; // scope 1 at $DIR/receiver_ptr_mutability.rs:+2:5: +2:12
                                          // mir::Constant
-                                         // + span: $DIR/receiver-ptr-mutability.rs:15:9: 15:10
+                                         // + span: $DIR/receiver_ptr_mutability.rs:15:9: 15:10
                                          // + literal: Const { ty: fn(*const Test) {Test::x}, val: Value(<ZST>) }
     }
 
     bb2: {
-        StorageDead(_3);                 // scope 1 at $DIR/receiver-ptr-mutability.rs:+2:11: +2:12
-        StorageDead(_2);                 // scope 1 at $DIR/receiver-ptr-mutability.rs:+2:12: +2:13
-        StorageLive(_5);                 // scope 1 at $DIR/receiver-ptr-mutability.rs:+5:9: +5:16
-        StorageLive(_6);                 // scope 1 at $DIR/receiver-ptr-mutability.rs:+5:34: +5:41
-        StorageLive(_7);                 // scope 1 at $DIR/receiver-ptr-mutability.rs:+5:35: +5:41
-        StorageLive(_8);                 // scope 1 at $DIR/receiver-ptr-mutability.rs:+5:36: +5:41
-        StorageLive(_9);                 // scope 1 at $DIR/receiver-ptr-mutability.rs:+5:37: +5:41
-        _9 = &_1;                        // scope 1 at $DIR/receiver-ptr-mutability.rs:+5:37: +5:41
-        _8 = &_9;                        // scope 1 at $DIR/receiver-ptr-mutability.rs:+5:36: +5:41
-        _7 = &_8;                        // scope 1 at $DIR/receiver-ptr-mutability.rs:+5:35: +5:41
-        _6 = &_7;                        // scope 1 at $DIR/receiver-ptr-mutability.rs:+5:34: +5:41
-        _5 = &(*_6);                     // scope 1 at $DIR/receiver-ptr-mutability.rs:+5:34: +5:41
-        FakeRead(ForLet(None), _5);      // scope 1 at $DIR/receiver-ptr-mutability.rs:+5:9: +5:16
-        AscribeUserType(_5, o, UserTypeProjection { base: UserType(3), projs: [] }); // scope 1 at $DIR/receiver-ptr-mutability.rs:+5:18: +5:31
-        StorageDead(_6);                 // scope 1 at $DIR/receiver-ptr-mutability.rs:+5:41: +5:42
-        StorageLive(_10);                // scope 2 at $DIR/receiver-ptr-mutability.rs:+6:5: +6:16
-        StorageLive(_11);                // scope 2 at $DIR/receiver-ptr-mutability.rs:+6:5: +6:16
-        StorageLive(_12);                // scope 2 at $DIR/receiver-ptr-mutability.rs:+6:5: +6:16
-        _12 = (*(*(*(*_5))));            // scope 2 at $DIR/receiver-ptr-mutability.rs:+6:5: +6:16
-        _11 = move _12 as *const Test (Pointer(MutToConstPointer)); // scope 2 at $DIR/receiver-ptr-mutability.rs:+6:5: +6:16
-        StorageDead(_12);                // scope 2 at $DIR/receiver-ptr-mutability.rs:+6:11: +6:12
-        _10 = Test::x(move _11) -> [return: bb3, unwind: bb4]; // scope 2 at $DIR/receiver-ptr-mutability.rs:+6:5: +6:16
+        StorageDead(_3);                 // scope 1 at $DIR/receiver_ptr_mutability.rs:+2:11: +2:12
+        StorageDead(_2);                 // scope 1 at $DIR/receiver_ptr_mutability.rs:+2:12: +2:13
+        StorageLive(_5);                 // scope 1 at $DIR/receiver_ptr_mutability.rs:+5:9: +5:16
+        StorageLive(_6);                 // scope 1 at $DIR/receiver_ptr_mutability.rs:+5:34: +5:41
+        StorageLive(_7);                 // scope 1 at $DIR/receiver_ptr_mutability.rs:+5:35: +5:41
+        StorageLive(_8);                 // scope 1 at $DIR/receiver_ptr_mutability.rs:+5:36: +5:41
+        StorageLive(_9);                 // scope 1 at $DIR/receiver_ptr_mutability.rs:+5:37: +5:41
+        _9 = &_1;                        // scope 1 at $DIR/receiver_ptr_mutability.rs:+5:37: +5:41
+        _8 = &_9;                        // scope 1 at $DIR/receiver_ptr_mutability.rs:+5:36: +5:41
+        _7 = &_8;                        // scope 1 at $DIR/receiver_ptr_mutability.rs:+5:35: +5:41
+        _6 = &_7;                        // scope 1 at $DIR/receiver_ptr_mutability.rs:+5:34: +5:41
+        _5 = &(*_6);                     // scope 1 at $DIR/receiver_ptr_mutability.rs:+5:34: +5:41
+        FakeRead(ForLet(None), _5);      // scope 1 at $DIR/receiver_ptr_mutability.rs:+5:9: +5:16
+        AscribeUserType(_5, o, UserTypeProjection { base: UserType(3), projs: [] }); // scope 1 at $DIR/receiver_ptr_mutability.rs:+5:18: +5:31
+        StorageDead(_6);                 // scope 1 at $DIR/receiver_ptr_mutability.rs:+5:41: +5:42
+        StorageLive(_10);                // scope 2 at $DIR/receiver_ptr_mutability.rs:+6:5: +6:16
+        StorageLive(_11);                // scope 2 at $DIR/receiver_ptr_mutability.rs:+6:5: +6:16
+        StorageLive(_12);                // scope 2 at $DIR/receiver_ptr_mutability.rs:+6:5: +6:16
+        _12 = (*(*(*(*_5))));            // scope 2 at $DIR/receiver_ptr_mutability.rs:+6:5: +6:16
+        _11 = move _12 as *const Test (Pointer(MutToConstPointer)); // scope 2 at $DIR/receiver_ptr_mutability.rs:+6:5: +6:16
+        StorageDead(_12);                // scope 2 at $DIR/receiver_ptr_mutability.rs:+6:11: +6:12
+        _10 = Test::x(move _11) -> [return: bb3, unwind: bb4]; // scope 2 at $DIR/receiver_ptr_mutability.rs:+6:5: +6:16
                                          // mir::Constant
-                                         // + span: $DIR/receiver-ptr-mutability.rs:19:13: 19:14
+                                         // + span: $DIR/receiver_ptr_mutability.rs:19:13: 19:14
                                          // + literal: Const { ty: fn(*const Test) {Test::x}, val: Value(<ZST>) }
     }
 
     bb3: {
-        StorageDead(_11);                // scope 2 at $DIR/receiver-ptr-mutability.rs:+6:15: +6:16
-        StorageDead(_10);                // scope 2 at $DIR/receiver-ptr-mutability.rs:+6:16: +6:17
-        _0 = const ();                   // scope 0 at $DIR/receiver-ptr-mutability.rs:+0:11: +7:2
-        StorageDead(_9);                 // scope 1 at $DIR/receiver-ptr-mutability.rs:+7:1: +7:2
-        StorageDead(_8);                 // scope 1 at $DIR/receiver-ptr-mutability.rs:+7:1: +7:2
-        StorageDead(_7);                 // scope 1 at $DIR/receiver-ptr-mutability.rs:+7:1: +7:2
-        StorageDead(_5);                 // scope 1 at $DIR/receiver-ptr-mutability.rs:+7:1: +7:2
-        StorageDead(_1);                 // scope 0 at $DIR/receiver-ptr-mutability.rs:+7:1: +7:2
-        return;                          // scope 0 at $DIR/receiver-ptr-mutability.rs:+7:2: +7:2
+        StorageDead(_11);                // scope 2 at $DIR/receiver_ptr_mutability.rs:+6:15: +6:16
+        StorageDead(_10);                // scope 2 at $DIR/receiver_ptr_mutability.rs:+6:16: +6:17
+        _0 = const ();                   // scope 0 at $DIR/receiver_ptr_mutability.rs:+0:11: +7:2
+        StorageDead(_9);                 // scope 1 at $DIR/receiver_ptr_mutability.rs:+7:1: +7:2
+        StorageDead(_8);                 // scope 1 at $DIR/receiver_ptr_mutability.rs:+7:1: +7:2
+        StorageDead(_7);                 // scope 1 at $DIR/receiver_ptr_mutability.rs:+7:1: +7:2
+        StorageDead(_5);                 // scope 1 at $DIR/receiver_ptr_mutability.rs:+7:1: +7:2
+        StorageDead(_1);                 // scope 0 at $DIR/receiver_ptr_mutability.rs:+7:1: +7:2
+        return;                          // scope 0 at $DIR/receiver_ptr_mutability.rs:+7:2: +7:2
     }
 
     bb4 (cleanup): {
-        resume;                          // scope 0 at $DIR/receiver-ptr-mutability.rs:+0:1: +7:2
+        resume;                          // scope 0 at $DIR/receiver_ptr_mutability.rs:+0:1: +7:2
     }
 }
diff --git a/src/test/mir-opt/receiver-ptr-mutability.rs b/src/test/mir-opt/building/receiver_ptr_mutability.rs
similarity index 83%
rename from src/test/mir-opt/receiver-ptr-mutability.rs
rename to src/test/mir-opt/building/receiver_ptr_mutability.rs
index 8e2ff0451c63..668530968fe5 100644
--- a/src/test/mir-opt/receiver-ptr-mutability.rs
+++ b/src/test/mir-opt/building/receiver_ptr_mutability.rs
@@ -1,4 +1,4 @@
-// EMIT_MIR receiver_ptr_mutability.main.mir_map.0.mir
+// EMIT_MIR receiver_ptr_mutability.main.built.after.mir
 
 #![feature(arbitrary_self_types)]
 
diff --git a/src/test/mir-opt/simple_match.match_bool.mir_map.0.mir b/src/test/mir-opt/building/simple_match.match_bool.built.after.mir
similarity index 70%
rename from src/test/mir-opt/simple_match.match_bool.mir_map.0.mir
rename to src/test/mir-opt/building/simple_match.match_bool.built.after.mir
index 3bef6aa0579a..a4516026c3b4 100644
--- a/src/test/mir-opt/simple_match.match_bool.mir_map.0.mir
+++ b/src/test/mir-opt/building/simple_match.match_bool.built.after.mir
@@ -1,29 +1,29 @@
-// MIR for `match_bool` 0 mir_map
+// MIR for `match_bool` after built
 
 fn match_bool(_1: bool) -> usize {
-    debug x => _1;                       // in scope 0 at $DIR/simple-match.rs:+0:15: +0:16
-    let mut _0: usize;                   // return place in scope 0 at $DIR/simple-match.rs:+0:27: +0:32
+    debug x => _1;                       // in scope 0 at $DIR/simple_match.rs:+0:15: +0:16
+    let mut _0: usize;                   // return place in scope 0 at $DIR/simple_match.rs:+0:27: +0:32
 
     bb0: {
-        FakeRead(ForMatchedPlace(None), _1); // scope 0 at $DIR/simple-match.rs:+1:11: +1:12
-        switchInt(_1) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/simple-match.rs:+1:5: +1:12
+        FakeRead(ForMatchedPlace(None), _1); // scope 0 at $DIR/simple_match.rs:+1:11: +1:12
+        switchInt(_1) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/simple_match.rs:+1:5: +1:12
     }
 
     bb1: {
-        falseEdge -> [real: bb3, imaginary: bb2]; // scope 0 at $DIR/simple-match.rs:+2:9: +2:13
+        falseEdge -> [real: bb3, imaginary: bb2]; // scope 0 at $DIR/simple_match.rs:+2:9: +2:13
     }
 
     bb2: {
-        _0 = const 20_usize;             // scope 0 at $DIR/simple-match.rs:+3:14: +3:16
-        goto -> bb4;                     // scope 0 at $DIR/simple-match.rs:+3:14: +3:16
+        _0 = const 20_usize;             // scope 0 at $DIR/simple_match.rs:+3:14: +3:16
+        goto -> bb4;                     // scope 0 at $DIR/simple_match.rs:+3:14: +3:16
     }
 
     bb3: {
-        _0 = const 10_usize;             // scope 0 at $DIR/simple-match.rs:+2:17: +2:19
-        goto -> bb4;                     // scope 0 at $DIR/simple-match.rs:+2:17: +2:19
+        _0 = const 10_usize;             // scope 0 at $DIR/simple_match.rs:+2:17: +2:19
+        goto -> bb4;                     // scope 0 at $DIR/simple_match.rs:+2:17: +2:19
     }
 
     bb4: {
-        return;                          // scope 0 at $DIR/simple-match.rs:+5:2: +5:2
+        return;                          // scope 0 at $DIR/simple_match.rs:+5:2: +5:2
     }
 }
diff --git a/src/test/mir-opt/simple-match.rs b/src/test/mir-opt/building/simple_match.rs
similarity index 78%
rename from src/test/mir-opt/simple-match.rs
rename to src/test/mir-opt/building/simple_match.rs
index 103033c4e2b8..0ef97dde6363 100644
--- a/src/test/mir-opt/simple-match.rs
+++ b/src/test/mir-opt/building/simple_match.rs
@@ -1,7 +1,7 @@
 // Test that we don't generate unnecessarily large MIR for very simple matches
 
 
-// EMIT_MIR simple_match.match_bool.mir_map.0.mir
+// EMIT_MIR simple_match.match_bool.built.after.mir
 fn match_bool(x: bool) -> usize {
     match x {
         true => 10,
diff --git a/src/test/mir-opt/storage_live_dead_in_statics.XXX.mir_map.0.mir b/src/test/mir-opt/building/storage_live_dead_in_statics.XXX.built.after.mir
similarity index 99%
rename from src/test/mir-opt/storage_live_dead_in_statics.XXX.mir_map.0.mir
rename to src/test/mir-opt/building/storage_live_dead_in_statics.XXX.built.after.mir
index e50067ea25ef..1d3f77e079ba 100644
--- a/src/test/mir-opt/storage_live_dead_in_statics.XXX.mir_map.0.mir
+++ b/src/test/mir-opt/building/storage_live_dead_in_statics.XXX.built.after.mir
@@ -1,4 +1,4 @@
-// MIR for `XXX` 0 mir_map
+// MIR for `XXX` after built
 
 static XXX: &Foo = {
     let mut _0: &Foo;                    // return place in scope 0 at $DIR/storage_live_dead_in_statics.rs:+0:13: +0:25
diff --git a/src/test/mir-opt/storage_live_dead_in_statics.rs b/src/test/mir-opt/building/storage_live_dead_in_statics.rs
similarity index 92%
rename from src/test/mir-opt/storage_live_dead_in_statics.rs
rename to src/test/mir-opt/building/storage_live_dead_in_statics.rs
index b03de8612fc1..79f709148e30 100644
--- a/src/test/mir-opt/storage_live_dead_in_statics.rs
+++ b/src/test/mir-opt/building/storage_live_dead_in_statics.rs
@@ -1,7 +1,7 @@
 // Check that when we compile the static `XXX` into MIR, we do not
 // generate `StorageStart` or `StorageEnd` statements.
 
-// EMIT_MIR storage_live_dead_in_statics.XXX.mir_map.0.mir
+// EMIT_MIR storage_live_dead_in_statics.XXX.built.after.mir
 static XXX: &'static Foo = &Foo {
     tup: "hi",
     data: &[
diff --git a/src/test/mir-opt/uniform_array_move_out.move_out_by_subslice.mir_map.0.mir b/src/test/mir-opt/building/uniform_array_move_out.move_out_by_subslice.built.after.mir
similarity index 99%
rename from src/test/mir-opt/uniform_array_move_out.move_out_by_subslice.mir_map.0.mir
rename to src/test/mir-opt/building/uniform_array_move_out.move_out_by_subslice.built.after.mir
index 6a5021139cf6..234cd0839773 100644
--- a/src/test/mir-opt/uniform_array_move_out.move_out_by_subslice.mir_map.0.mir
+++ b/src/test/mir-opt/building/uniform_array_move_out.move_out_by_subslice.built.after.mir
@@ -1,4 +1,4 @@
-// MIR for `move_out_by_subslice` 0 mir_map
+// MIR for `move_out_by_subslice` after built
 
 fn move_out_by_subslice() -> () {
     let mut _0: ();                      // return place in scope 0 at $DIR/uniform_array_move_out.rs:+0:27: +0:27
diff --git a/src/test/mir-opt/uniform_array_move_out.move_out_from_end.mir_map.0.mir b/src/test/mir-opt/building/uniform_array_move_out.move_out_from_end.built.after.mir
similarity index 99%
rename from src/test/mir-opt/uniform_array_move_out.move_out_from_end.mir_map.0.mir
rename to src/test/mir-opt/building/uniform_array_move_out.move_out_from_end.built.after.mir
index 23a50b22ad14..24a189498d34 100644
--- a/src/test/mir-opt/uniform_array_move_out.move_out_from_end.mir_map.0.mir
+++ b/src/test/mir-opt/building/uniform_array_move_out.move_out_from_end.built.after.mir
@@ -1,4 +1,4 @@
-// MIR for `move_out_from_end` 0 mir_map
+// MIR for `move_out_from_end` after built
 
 fn move_out_from_end() -> () {
     let mut _0: ();                      // return place in scope 0 at $DIR/uniform_array_move_out.rs:+0:24: +0:24
diff --git a/src/test/mir-opt/uniform_array_move_out.rs b/src/test/mir-opt/building/uniform_array_move_out.rs
similarity index 64%
rename from src/test/mir-opt/uniform_array_move_out.rs
rename to src/test/mir-opt/building/uniform_array_move_out.rs
index 35e425528700..e925036ecf69 100644
--- a/src/test/mir-opt/uniform_array_move_out.rs
+++ b/src/test/mir-opt/building/uniform_array_move_out.rs
@@ -1,12 +1,12 @@
 #![feature(box_syntax)]
 
-// EMIT_MIR uniform_array_move_out.move_out_from_end.mir_map.0.mir
+// EMIT_MIR uniform_array_move_out.move_out_from_end.built.after.mir
 fn move_out_from_end() {
     let a = [box 1, box 2];
     let [.., _y] = a;
 }
 
-// EMIT_MIR uniform_array_move_out.move_out_by_subslice.mir_map.0.mir
+// EMIT_MIR uniform_array_move_out.move_out_by_subslice.built.after.mir
 fn move_out_by_subslice() {
     let a = [box 1, box 2];
     let [_y @ ..] = a;
diff --git a/src/test/mir-opt/const_promotion_extern_static.BAR-promoted[0].SimplifyCfg-elaborate-drops.after.mir b/src/test/mir-opt/const_promotion_extern_static.BAR-promoted[0].SimplifyCfg-elaborate-drops.after.mir
index 7650769de3b5..028480bdc88b 100644
--- a/src/test/mir-opt/const_promotion_extern_static.BAR-promoted[0].SimplifyCfg-elaborate-drops.after.mir
+++ b/src/test/mir-opt/const_promotion_extern_static.BAR-promoted[0].SimplifyCfg-elaborate-drops.after.mir
@@ -1,20 +1,20 @@
 // MIR for `BAR::promoted[0]` after SimplifyCfg-elaborate-drops
 
 promoted[0] in BAR: &[&i32; 1] = {
-    let mut _0: &[&i32; 1];              // return place in scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:44
-    let mut _1: [&i32; 1];               // in scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:35
-    let mut _2: &i32;                    // in scope 0 at $DIR/const-promotion-extern-static.rs:+0:32: +0:34
-    let mut _3: &i32;                    // in scope 0 at $DIR/const-promotion-extern-static.rs:+0:33: +0:34
+    let mut _0: &[&i32; 1];              // return place in scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:44
+    let mut _1: [&i32; 1];               // in scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:35
+    let mut _2: &i32;                    // in scope 0 at $DIR/const_promotion_extern_static.rs:+0:32: +0:34
+    let mut _3: &i32;                    // in scope 0 at $DIR/const_promotion_extern_static.rs:+0:33: +0:34
 
     bb0: {
-        _3 = const {alloc1: &i32};       // scope 0 at $DIR/const-promotion-extern-static.rs:+0:33: +0:34
+        _3 = const {alloc1: &i32};       // scope 0 at $DIR/const_promotion_extern_static.rs:+0:33: +0:34
                                          // mir::Constant
-                                         // + span: $DIR/const-promotion-extern-static.rs:9:33: 9:34
+                                         // + span: $DIR/const_promotion_extern_static.rs:9:33: 9:34
                                          // + literal: Const { ty: &i32, val: Value(Scalar(alloc1)) }
-        _2 = &(*_3);                     // scope 0 at $DIR/const-promotion-extern-static.rs:+0:32: +0:34
-        _1 = [move _2];                  // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:35
-        _0 = &_1;                        // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:44
-        return;                          // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:44
+        _2 = &(*_3);                     // scope 0 at $DIR/const_promotion_extern_static.rs:+0:32: +0:34
+        _1 = [move _2];                  // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:35
+        _0 = &_1;                        // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:44
+        return;                          // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:44
     }
 }
 
diff --git a/src/test/mir-opt/const_promotion_extern_static.BAR.PromoteTemps.diff b/src/test/mir-opt/const_promotion_extern_static.BAR.PromoteTemps.diff
index f8a7c687e124..2ef4378115fb 100644
--- a/src/test/mir-opt/const_promotion_extern_static.BAR.PromoteTemps.diff
+++ b/src/test/mir-opt/const_promotion_extern_static.BAR.PromoteTemps.diff
@@ -2,49 +2,49 @@
 + // MIR for `BAR` after PromoteTemps
   
   static mut BAR: *const &i32 = {
-      let mut _0: *const &i32;             // return place in scope 0 at $DIR/const-promotion-extern-static.rs:+0:17: +0:28
-      let mut _1: &[&i32];                 // in scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:44
-      let mut _2: &[&i32; 1];              // in scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:44
-      let _3: [&i32; 1];                   // in scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:35
-      let mut _4: &i32;                    // in scope 0 at $DIR/const-promotion-extern-static.rs:+0:32: +0:34
-      let _5: &i32;                        // in scope 0 at $DIR/const-promotion-extern-static.rs:+0:33: +0:34
-+     let mut _6: &[&i32; 1];              // in scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:44
+      let mut _0: *const &i32;             // return place in scope 0 at $DIR/const_promotion_extern_static.rs:+0:17: +0:28
+      let mut _1: &[&i32];                 // in scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:44
+      let mut _2: &[&i32; 1];              // in scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:44
+      let _3: [&i32; 1];                   // in scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:35
+      let mut _4: &i32;                    // in scope 0 at $DIR/const_promotion_extern_static.rs:+0:32: +0:34
+      let _5: &i32;                        // in scope 0 at $DIR/const_promotion_extern_static.rs:+0:33: +0:34
++     let mut _6: &[&i32; 1];              // in scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:44
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:44
-          StorageLive(_2);                 // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:44
--         StorageLive(_3);                 // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:35
--         StorageLive(_4);                 // scope 0 at $DIR/const-promotion-extern-static.rs:+0:32: +0:34
--         StorageLive(_5);                 // scope 0 at $DIR/const-promotion-extern-static.rs:+0:33: +0:34
--         _5 = const {alloc1: &i32};       // scope 0 at $DIR/const-promotion-extern-static.rs:+0:33: +0:34
-+         _6 = const _;                    // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:44
+          StorageLive(_1);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:44
+          StorageLive(_2);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:44
+-         StorageLive(_3);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:35
+-         StorageLive(_4);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:32: +0:34
+-         StorageLive(_5);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:33: +0:34
+-         _5 = const {alloc1: &i32};       // scope 0 at $DIR/const_promotion_extern_static.rs:+0:33: +0:34
++         _6 = const _;                    // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:44
                                            // mir::Constant
--                                          // + span: $DIR/const-promotion-extern-static.rs:9:33: 9:34
+-                                          // + span: $DIR/const_promotion_extern_static.rs:9:33: 9:34
 -                                          // + literal: Const { ty: &i32, val: Value(Scalar(alloc1)) }
--         _4 = &(*_5);                     // scope 0 at $DIR/const-promotion-extern-static.rs:+0:32: +0:34
--         _3 = [move _4];                  // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:35
--         _2 = &_3;                        // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:44
-+                                          // + span: $DIR/const-promotion-extern-static.rs:9:31: 9:44
+-         _4 = &(*_5);                     // scope 0 at $DIR/const_promotion_extern_static.rs:+0:32: +0:34
+-         _3 = [move _4];                  // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:35
+-         _2 = &_3;                        // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:44
++                                          // + span: $DIR/const_promotion_extern_static.rs:9:31: 9:44
 +                                          // + literal: Const { ty: &[&i32; 1], val: Unevaluated(BAR, [], Some(promoted[0])) }
-+         _2 = &(*_6);                     // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:44
-          _1 = move _2 as &[&i32] (Pointer(Unsize)); // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:44
--         StorageDead(_4);                 // scope 0 at $DIR/const-promotion-extern-static.rs:+0:34: +0:35
-          StorageDead(_2);                 // scope 0 at $DIR/const-promotion-extern-static.rs:+0:34: +0:35
-          _0 = core::slice::<impl [&i32]>::as_ptr(move _1) -> [return: bb1, unwind: bb2]; // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:44
++         _2 = &(*_6);                     // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:44
+          _1 = move _2 as &[&i32] (Pointer(Unsize)); // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:44
+-         StorageDead(_4);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:34: +0:35
+          StorageDead(_2);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:34: +0:35
+          _0 = core::slice::<impl [&i32]>::as_ptr(move _1) -> [return: bb1, unwind: bb2]; // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:44
                                            // mir::Constant
-                                           // + span: $DIR/const-promotion-extern-static.rs:9:36: 9:42
+                                           // + span: $DIR/const_promotion_extern_static.rs:9:36: 9:42
                                            // + literal: Const { ty: for<'a> fn(&'a [&i32]) -> *const &i32 {core::slice::<impl [&i32]>::as_ptr}, val: Value(<ZST>) }
       }
   
       bb1: {
--         StorageDead(_5);                 // scope 0 at $DIR/const-promotion-extern-static.rs:+0:43: +0:44
--         StorageDead(_3);                 // scope 0 at $DIR/const-promotion-extern-static.rs:+0:43: +0:44
-          StorageDead(_1);                 // scope 0 at $DIR/const-promotion-extern-static.rs:+0:43: +0:44
-          return;                          // scope 0 at $DIR/const-promotion-extern-static.rs:+0:1: +0:45
+-         StorageDead(_5);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:43: +0:44
+-         StorageDead(_3);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:43: +0:44
+          StorageDead(_1);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:43: +0:44
+          return;                          // scope 0 at $DIR/const_promotion_extern_static.rs:+0:1: +0:45
       }
   
       bb2 (cleanup): {
-          resume;                          // scope 0 at $DIR/const-promotion-extern-static.rs:+0:1: +0:45
+          resume;                          // scope 0 at $DIR/const_promotion_extern_static.rs:+0:1: +0:45
       }
 - }
 - 
diff --git a/src/test/mir-opt/const_promotion_extern_static.BOP.mir_map.0.mir b/src/test/mir-opt/const_promotion_extern_static.BOP.built.after.mir
similarity index 59%
rename from src/test/mir-opt/const_promotion_extern_static.BOP.mir_map.0.mir
rename to src/test/mir-opt/const_promotion_extern_static.BOP.built.after.mir
index 90920fbe7f80..476fc49a1fe1 100644
--- a/src/test/mir-opt/const_promotion_extern_static.BOP.mir_map.0.mir
+++ b/src/test/mir-opt/const_promotion_extern_static.BOP.built.after.mir
@@ -1,17 +1,17 @@
-// MIR for `BOP` 0 mir_map
+// MIR for `BOP` after built
 
 static BOP: &i32 = {
-    let mut _0: &i32;                    // return place in scope 0 at $DIR/const-promotion-extern-static.rs:+0:13: +0:17
-    let _1: &i32;                        // in scope 0 at $DIR/const-promotion-extern-static.rs:+0:20: +0:23
-    let _2: i32;                         // in scope 0 at $DIR/const-promotion-extern-static.rs:+0:21: +0:23
+    let mut _0: &i32;                    // return place in scope 0 at $DIR/const_promotion_extern_static.rs:+0:13: +0:17
+    let _1: &i32;                        // in scope 0 at $DIR/const_promotion_extern_static.rs:+0:20: +0:23
+    let _2: i32;                         // in scope 0 at $DIR/const_promotion_extern_static.rs:+0:21: +0:23
 
     bb0: {
-        StorageLive(_1);                 // scope 0 at $DIR/const-promotion-extern-static.rs:+0:20: +0:23
-        StorageLive(_2);                 // scope 0 at $DIR/const-promotion-extern-static.rs:+0:21: +0:23
-        _2 = const 13_i32;               // scope 0 at $DIR/const-promotion-extern-static.rs:+0:21: +0:23
-        _1 = &_2;                        // scope 0 at $DIR/const-promotion-extern-static.rs:+0:20: +0:23
-        _0 = &(*_1);                     // scope 0 at $DIR/const-promotion-extern-static.rs:+0:20: +0:23
-        StorageDead(_1);                 // scope 0 at $DIR/const-promotion-extern-static.rs:+0:22: +0:23
-        return;                          // scope 0 at $DIR/const-promotion-extern-static.rs:+0:1: +0:24
+        StorageLive(_1);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:20: +0:23
+        StorageLive(_2);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:21: +0:23
+        _2 = const 13_i32;               // scope 0 at $DIR/const_promotion_extern_static.rs:+0:21: +0:23
+        _1 = &_2;                        // scope 0 at $DIR/const_promotion_extern_static.rs:+0:20: +0:23
+        _0 = &(*_1);                     // scope 0 at $DIR/const_promotion_extern_static.rs:+0:20: +0:23
+        StorageDead(_1);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:22: +0:23
+        return;                          // scope 0 at $DIR/const_promotion_extern_static.rs:+0:1: +0:24
     }
 }
diff --git a/src/test/mir-opt/const_promotion_extern_static.FOO-promoted[0].SimplifyCfg-elaborate-drops.after.mir b/src/test/mir-opt/const_promotion_extern_static.FOO-promoted[0].SimplifyCfg-elaborate-drops.after.mir
index 71827eab1c28..41657b53fc12 100644
--- a/src/test/mir-opt/const_promotion_extern_static.FOO-promoted[0].SimplifyCfg-elaborate-drops.after.mir
+++ b/src/test/mir-opt/const_promotion_extern_static.FOO-promoted[0].SimplifyCfg-elaborate-drops.after.mir
@@ -1,20 +1,20 @@
 // MIR for `FOO::promoted[0]` after SimplifyCfg-elaborate-drops
 
 promoted[0] in FOO: &[&i32; 1] = {
-    let mut _0: &[&i32; 1];              // return place in scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:55
-    let mut _1: [&i32; 1];               // in scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:46
-    let mut _2: &i32;                    // in scope 0 at $DIR/const-promotion-extern-static.rs:+0:32: +0:45
-    let mut _3: *const i32;              // in scope 0 at $DIR/const-promotion-extern-static.rs:+0:42: +0:43
+    let mut _0: &[&i32; 1];              // return place in scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:55
+    let mut _1: [&i32; 1];               // in scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:46
+    let mut _2: &i32;                    // in scope 0 at $DIR/const_promotion_extern_static.rs:+0:32: +0:45
+    let mut _3: *const i32;              // in scope 0 at $DIR/const_promotion_extern_static.rs:+0:42: +0:43
 
     bb0: {
-        _3 = const {alloc3: *const i32}; // scope 0 at $DIR/const-promotion-extern-static.rs:+0:42: +0:43
+        _3 = const {alloc3: *const i32}; // scope 0 at $DIR/const_promotion_extern_static.rs:+0:42: +0:43
                                          // mir::Constant
-                                         // + span: $DIR/const-promotion-extern-static.rs:13:42: 13:43
+                                         // + span: $DIR/const_promotion_extern_static.rs:13:42: 13:43
                                          // + literal: Const { ty: *const i32, val: Value(Scalar(alloc3)) }
-        _2 = &(*_3);                     // scope 0 at $DIR/const-promotion-extern-static.rs:+0:41: +0:43
-        _1 = [move _2];                  // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:46
-        _0 = &_1;                        // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:55
-        return;                          // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:55
+        _2 = &(*_3);                     // scope 0 at $DIR/const_promotion_extern_static.rs:+0:41: +0:43
+        _1 = [move _2];                  // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:46
+        _0 = &_1;                        // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:55
+        return;                          // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:55
     }
 }
 
diff --git a/src/test/mir-opt/const_promotion_extern_static.FOO.PromoteTemps.diff b/src/test/mir-opt/const_promotion_extern_static.FOO.PromoteTemps.diff
index e938ca28af5d..25ba0face6bd 100644
--- a/src/test/mir-opt/const_promotion_extern_static.FOO.PromoteTemps.diff
+++ b/src/test/mir-opt/const_promotion_extern_static.FOO.PromoteTemps.diff
@@ -2,51 +2,51 @@
 + // MIR for `FOO` after PromoteTemps
   
   static mut FOO: *const &i32 = {
-      let mut _0: *const &i32;             // return place in scope 0 at $DIR/const-promotion-extern-static.rs:+0:17: +0:28
-      let mut _1: &[&i32];                 // in scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:55
-      let mut _2: &[&i32; 1];              // in scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:55
-      let _3: [&i32; 1];                   // in scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:46
-      let mut _4: &i32;                    // in scope 0 at $DIR/const-promotion-extern-static.rs:+0:32: +0:45
-      let _5: *const i32;                  // in scope 0 at $DIR/const-promotion-extern-static.rs:+0:42: +0:43
-+     let mut _6: &[&i32; 1];              // in scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:55
+      let mut _0: *const &i32;             // return place in scope 0 at $DIR/const_promotion_extern_static.rs:+0:17: +0:28
+      let mut _1: &[&i32];                 // in scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:55
+      let mut _2: &[&i32; 1];              // in scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:55
+      let _3: [&i32; 1];                   // in scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:46
+      let mut _4: &i32;                    // in scope 0 at $DIR/const_promotion_extern_static.rs:+0:32: +0:45
+      let _5: *const i32;                  // in scope 0 at $DIR/const_promotion_extern_static.rs:+0:42: +0:43
++     let mut _6: &[&i32; 1];              // in scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:55
       scope 1 {
       }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:55
-          StorageLive(_2);                 // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:55
--         StorageLive(_3);                 // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:46
--         StorageLive(_4);                 // scope 0 at $DIR/const-promotion-extern-static.rs:+0:32: +0:45
--         StorageLive(_5);                 // scope 1 at $DIR/const-promotion-extern-static.rs:+0:42: +0:43
--         _5 = const {alloc3: *const i32}; // scope 1 at $DIR/const-promotion-extern-static.rs:+0:42: +0:43
-+         _6 = const _;                    // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:55
+          StorageLive(_1);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:55
+          StorageLive(_2);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:55
+-         StorageLive(_3);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:46
+-         StorageLive(_4);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:32: +0:45
+-         StorageLive(_5);                 // scope 1 at $DIR/const_promotion_extern_static.rs:+0:42: +0:43
+-         _5 = const {alloc3: *const i32}; // scope 1 at $DIR/const_promotion_extern_static.rs:+0:42: +0:43
++         _6 = const _;                    // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:55
                                            // mir::Constant
--                                          // + span: $DIR/const-promotion-extern-static.rs:13:42: 13:43
+-                                          // + span: $DIR/const_promotion_extern_static.rs:13:42: 13:43
 -                                          // + literal: Const { ty: *const i32, val: Value(Scalar(alloc3)) }
--         _4 = &(*_5);                     // scope 1 at $DIR/const-promotion-extern-static.rs:+0:41: +0:43
--         _3 = [move _4];                  // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:46
--         _2 = &_3;                        // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:55
-+                                          // + span: $DIR/const-promotion-extern-static.rs:13:31: 13:55
+-         _4 = &(*_5);                     // scope 1 at $DIR/const_promotion_extern_static.rs:+0:41: +0:43
+-         _3 = [move _4];                  // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:46
+-         _2 = &_3;                        // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:55
++                                          // + span: $DIR/const_promotion_extern_static.rs:13:31: 13:55
 +                                          // + literal: Const { ty: &[&i32; 1], val: Unevaluated(FOO, [], Some(promoted[0])) }
-+         _2 = &(*_6);                     // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:55
-          _1 = move _2 as &[&i32] (Pointer(Unsize)); // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:55
--         StorageDead(_4);                 // scope 0 at $DIR/const-promotion-extern-static.rs:+0:45: +0:46
-          StorageDead(_2);                 // scope 0 at $DIR/const-promotion-extern-static.rs:+0:45: +0:46
-          _0 = core::slice::<impl [&i32]>::as_ptr(move _1) -> [return: bb1, unwind: bb2]; // scope 0 at $DIR/const-promotion-extern-static.rs:+0:31: +0:55
++         _2 = &(*_6);                     // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:55
+          _1 = move _2 as &[&i32] (Pointer(Unsize)); // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:55
+-         StorageDead(_4);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:45: +0:46
+          StorageDead(_2);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:45: +0:46
+          _0 = core::slice::<impl [&i32]>::as_ptr(move _1) -> [return: bb1, unwind: bb2]; // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:55
                                            // mir::Constant
-                                           // + span: $DIR/const-promotion-extern-static.rs:13:47: 13:53
+                                           // + span: $DIR/const_promotion_extern_static.rs:13:47: 13:53
                                            // + literal: Const { ty: for<'a> fn(&'a [&i32]) -> *const &i32 {core::slice::<impl [&i32]>::as_ptr}, val: Value(<ZST>) }
       }
   
       bb1: {
--         StorageDead(_5);                 // scope 0 at $DIR/const-promotion-extern-static.rs:+0:54: +0:55
--         StorageDead(_3);                 // scope 0 at $DIR/const-promotion-extern-static.rs:+0:54: +0:55
-          StorageDead(_1);                 // scope 0 at $DIR/const-promotion-extern-static.rs:+0:54: +0:55
-          return;                          // scope 0 at $DIR/const-promotion-extern-static.rs:+0:1: +0:56
+-         StorageDead(_5);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:54: +0:55
+-         StorageDead(_3);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:54: +0:55
+          StorageDead(_1);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:54: +0:55
+          return;                          // scope 0 at $DIR/const_promotion_extern_static.rs:+0:1: +0:56
       }
   
       bb2 (cleanup): {
-          resume;                          // scope 0 at $DIR/const-promotion-extern-static.rs:+0:1: +0:56
+          resume;                          // scope 0 at $DIR/const_promotion_extern_static.rs:+0:1: +0:56
       }
   }
 - 
diff --git a/src/test/mir-opt/const-promotion-extern-static.rs b/src/test/mir-opt/const_promotion_extern_static.rs
similarity index 89%
rename from src/test/mir-opt/const-promotion-extern-static.rs
rename to src/test/mir-opt/const_promotion_extern_static.rs
index a0d4e9b2c65a..e4261cfe5044 100644
--- a/src/test/mir-opt/const-promotion-extern-static.rs
+++ b/src/test/mir-opt/const_promotion_extern_static.rs
@@ -12,7 +12,7 @@ static mut BAR: *const &i32 = [&Y].as_ptr();
 // EMIT_MIR const_promotion_extern_static.FOO-promoted[0].SimplifyCfg-elaborate-drops.after.mir
 static mut FOO: *const &i32 = [unsafe { &X }].as_ptr();
 
-// EMIT_MIR const_promotion_extern_static.BOP.mir_map.0.mir
+// EMIT_MIR const_promotion_extern_static.BOP.built.after.mir
 static BOP: &i32 = &13;
 
 fn main() {}
diff --git a/src/test/mir-opt/const_prop/control_flow_simplification.hello.ConstProp.diff b/src/test/mir-opt/const_prop/control_flow_simplification.hello.ConstProp.diff
index a07bdd99825d..8b3b9d0a4c1b 100644
--- a/src/test/mir-opt/const_prop/control_flow_simplification.hello.ConstProp.diff
+++ b/src/test/mir-opt/const_prop/control_flow_simplification.hello.ConstProp.diff
@@ -2,15 +2,15 @@
 + // MIR for `hello` after ConstProp
   
   fn hello() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/control-flow-simplification.rs:+0:14: +0:14
-      let mut _1: bool;                    // in scope 0 at $DIR/control-flow-simplification.rs:+1:8: +1:21
+      let mut _0: ();                      // return place in scope 0 at $DIR/control_flow_simplification.rs:+0:14: +0:14
+      let mut _1: bool;                    // in scope 0 at $DIR/control_flow_simplification.rs:+1:8: +1:21
       let mut _2: !;                       // in scope 0 at $SRC_DIR/std/src/panic.rs:LL:COL
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/control-flow-simplification.rs:+1:8: +1:21
-          _1 = const _;                    // scope 0 at $DIR/control-flow-simplification.rs:+1:8: +1:21
--         switchInt(move _1) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/control-flow-simplification.rs:+1:8: +1:21
-+         switchInt(const false) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/control-flow-simplification.rs:+1:8: +1:21
+          StorageLive(_1);                 // scope 0 at $DIR/control_flow_simplification.rs:+1:8: +1:21
+          _1 = const _;                    // scope 0 at $DIR/control_flow_simplification.rs:+1:8: +1:21
+-         switchInt(move _1) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/control_flow_simplification.rs:+1:8: +1:21
++         switchInt(const false) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/control_flow_simplification.rs:+1:8: +1:21
       }
   
       bb1: {
@@ -25,9 +25,9 @@
       }
   
       bb2: {
-          nop;                             // scope 0 at $DIR/control-flow-simplification.rs:+3:6: +3:6
-          StorageDead(_1);                 // scope 0 at $DIR/control-flow-simplification.rs:+3:5: +3:6
-          return;                          // scope 0 at $DIR/control-flow-simplification.rs:+4:2: +4:2
+          nop;                             // scope 0 at $DIR/control_flow_simplification.rs:+3:6: +3:6
+          StorageDead(_1);                 // scope 0 at $DIR/control_flow_simplification.rs:+3:5: +3:6
+          return;                          // scope 0 at $DIR/control_flow_simplification.rs:+4:2: +4:2
       }
   }
   
diff --git a/src/test/mir-opt/const_prop/control_flow_simplification.hello.PreCodegen.before.mir b/src/test/mir-opt/const_prop/control_flow_simplification.hello.PreCodegen.before.mir
index 70f979775113..9f7528f0ce17 100644
--- a/src/test/mir-opt/const_prop/control_flow_simplification.hello.PreCodegen.before.mir
+++ b/src/test/mir-opt/const_prop/control_flow_simplification.hello.PreCodegen.before.mir
@@ -1,9 +1,9 @@
 // MIR for `hello` before PreCodegen
 
 fn hello() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/control-flow-simplification.rs:+0:14: +0:14
+    let mut _0: ();                      // return place in scope 0 at $DIR/control_flow_simplification.rs:+0:14: +0:14
 
     bb0: {
-        return;                          // scope 0 at $DIR/control-flow-simplification.rs:+4:2: +4:2
+        return;                          // scope 0 at $DIR/control_flow_simplification.rs:+4:2: +4:2
     }
 }
diff --git a/src/test/mir-opt/const_prop/control-flow-simplification.rs b/src/test/mir-opt/const_prop/control_flow_simplification.rs
similarity index 100%
rename from src/test/mir-opt/const_prop/control-flow-simplification.rs
rename to src/test/mir-opt/const_prop/control_flow_simplification.rs
diff --git a/src/test/mir-opt/const_prop/issue_66971.main.ConstProp.diff b/src/test/mir-opt/const_prop/issue_66971.main.ConstProp.diff
index 9d541dcabbb2..7d8e647cbced 100644
--- a/src/test/mir-opt/const_prop/issue_66971.main.ConstProp.diff
+++ b/src/test/mir-opt/const_prop/issue_66971.main.ConstProp.diff
@@ -2,32 +2,32 @@
 + // MIR for `main` after ConstProp
   
   fn main() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/issue-66971.rs:+0:11: +0:11
-      let _1: ();                          // in scope 0 at $DIR/issue-66971.rs:+1:5: +1:23
-      let mut _2: ((), u8, u8);            // in scope 0 at $DIR/issue-66971.rs:+1:12: +1:22
-      let mut _3: ();                      // in scope 0 at $DIR/issue-66971.rs:+1:13: +1:15
+      let mut _0: ();                      // return place in scope 0 at $DIR/issue_66971.rs:+0:11: +0:11
+      let _1: ();                          // in scope 0 at $DIR/issue_66971.rs:+1:5: +1:23
+      let mut _2: ((), u8, u8);            // in scope 0 at $DIR/issue_66971.rs:+1:12: +1:22
+      let mut _3: ();                      // in scope 0 at $DIR/issue_66971.rs:+1:13: +1:15
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/issue-66971.rs:+1:5: +1:23
-          StorageLive(_2);                 // scope 0 at $DIR/issue-66971.rs:+1:12: +1:22
-          StorageLive(_3);                 // scope 0 at $DIR/issue-66971.rs:+1:13: +1:15
-          nop;                             // scope 0 at $DIR/issue-66971.rs:+1:13: +1:15
-          Deinit(_2);                      // scope 0 at $DIR/issue-66971.rs:+1:12: +1:22
-          nop;                             // scope 0 at $DIR/issue-66971.rs:+1:12: +1:22
-          (_2.1: u8) = const 0_u8;         // scope 0 at $DIR/issue-66971.rs:+1:12: +1:22
-          (_2.2: u8) = const 0_u8;         // scope 0 at $DIR/issue-66971.rs:+1:12: +1:22
-          StorageDead(_3);                 // scope 0 at $DIR/issue-66971.rs:+1:21: +1:22
-          _1 = encode(move _2) -> bb1;     // scope 0 at $DIR/issue-66971.rs:+1:5: +1:23
+          StorageLive(_1);                 // scope 0 at $DIR/issue_66971.rs:+1:5: +1:23
+          StorageLive(_2);                 // scope 0 at $DIR/issue_66971.rs:+1:12: +1:22
+          StorageLive(_3);                 // scope 0 at $DIR/issue_66971.rs:+1:13: +1:15
+          nop;                             // scope 0 at $DIR/issue_66971.rs:+1:13: +1:15
+          Deinit(_2);                      // scope 0 at $DIR/issue_66971.rs:+1:12: +1:22
+          nop;                             // scope 0 at $DIR/issue_66971.rs:+1:12: +1:22
+          (_2.1: u8) = const 0_u8;         // scope 0 at $DIR/issue_66971.rs:+1:12: +1:22
+          (_2.2: u8) = const 0_u8;         // scope 0 at $DIR/issue_66971.rs:+1:12: +1:22
+          StorageDead(_3);                 // scope 0 at $DIR/issue_66971.rs:+1:21: +1:22
+          _1 = encode(move _2) -> bb1;     // scope 0 at $DIR/issue_66971.rs:+1:5: +1:23
                                            // mir::Constant
-                                           // + span: $DIR/issue-66971.rs:17:5: 17:11
+                                           // + span: $DIR/issue_66971.rs:17:5: 17:11
                                            // + literal: Const { ty: fn(((), u8, u8)) {encode}, val: Value(<ZST>) }
       }
   
       bb1: {
-          StorageDead(_2);                 // scope 0 at $DIR/issue-66971.rs:+1:22: +1:23
-          StorageDead(_1);                 // scope 0 at $DIR/issue-66971.rs:+1:23: +1:24
-          nop;                             // scope 0 at $DIR/issue-66971.rs:+0:11: +2:2
-          return;                          // scope 0 at $DIR/issue-66971.rs:+2:2: +2:2
+          StorageDead(_2);                 // scope 0 at $DIR/issue_66971.rs:+1:22: +1:23
+          StorageDead(_1);                 // scope 0 at $DIR/issue_66971.rs:+1:23: +1:24
+          nop;                             // scope 0 at $DIR/issue_66971.rs:+0:11: +2:2
+          return;                          // scope 0 at $DIR/issue_66971.rs:+2:2: +2:2
       }
   }
   
diff --git a/src/test/mir-opt/const_prop/issue-66971.rs b/src/test/mir-opt/const_prop/issue_66971.rs
similarity index 100%
rename from src/test/mir-opt/const_prop/issue-66971.rs
rename to src/test/mir-opt/const_prop/issue_66971.rs
diff --git a/src/test/mir-opt/const_prop/issue_67019.main.ConstProp.diff b/src/test/mir-opt/const_prop/issue_67019.main.ConstProp.diff
index b79d814760d9..79cd8bf48396 100644
--- a/src/test/mir-opt/const_prop/issue_67019.main.ConstProp.diff
+++ b/src/test/mir-opt/const_prop/issue_67019.main.ConstProp.diff
@@ -2,33 +2,33 @@
 + // MIR for `main` after ConstProp
   
   fn main() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/issue-67019.rs:+0:11: +0:11
-      let _1: ();                          // in scope 0 at $DIR/issue-67019.rs:+1:5: +1:20
-      let mut _2: ((u8, u8),);             // in scope 0 at $DIR/issue-67019.rs:+1:10: +1:19
-      let mut _3: (u8, u8);                // in scope 0 at $DIR/issue-67019.rs:+1:11: +1:17
+      let mut _0: ();                      // return place in scope 0 at $DIR/issue_67019.rs:+0:11: +0:11
+      let _1: ();                          // in scope 0 at $DIR/issue_67019.rs:+1:5: +1:20
+      let mut _2: ((u8, u8),);             // in scope 0 at $DIR/issue_67019.rs:+1:10: +1:19
+      let mut _3: (u8, u8);                // in scope 0 at $DIR/issue_67019.rs:+1:11: +1:17
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/issue-67019.rs:+1:5: +1:20
-          StorageLive(_2);                 // scope 0 at $DIR/issue-67019.rs:+1:10: +1:19
-          StorageLive(_3);                 // scope 0 at $DIR/issue-67019.rs:+1:11: +1:17
-          Deinit(_3);                      // scope 0 at $DIR/issue-67019.rs:+1:11: +1:17
-          (_3.0: u8) = const 1_u8;         // scope 0 at $DIR/issue-67019.rs:+1:11: +1:17
-          (_3.1: u8) = const 2_u8;         // scope 0 at $DIR/issue-67019.rs:+1:11: +1:17
-          Deinit(_2);                      // scope 0 at $DIR/issue-67019.rs:+1:10: +1:19
--         (_2.0: (u8, u8)) = move _3;      // scope 0 at $DIR/issue-67019.rs:+1:10: +1:19
-+         (_2.0: (u8, u8)) = const (1_u8, 2_u8); // scope 0 at $DIR/issue-67019.rs:+1:10: +1:19
-          StorageDead(_3);                 // scope 0 at $DIR/issue-67019.rs:+1:18: +1:19
-          _1 = test(move _2) -> bb1;       // scope 0 at $DIR/issue-67019.rs:+1:5: +1:20
+          StorageLive(_1);                 // scope 0 at $DIR/issue_67019.rs:+1:5: +1:20
+          StorageLive(_2);                 // scope 0 at $DIR/issue_67019.rs:+1:10: +1:19
+          StorageLive(_3);                 // scope 0 at $DIR/issue_67019.rs:+1:11: +1:17
+          Deinit(_3);                      // scope 0 at $DIR/issue_67019.rs:+1:11: +1:17
+          (_3.0: u8) = const 1_u8;         // scope 0 at $DIR/issue_67019.rs:+1:11: +1:17
+          (_3.1: u8) = const 2_u8;         // scope 0 at $DIR/issue_67019.rs:+1:11: +1:17
+          Deinit(_2);                      // scope 0 at $DIR/issue_67019.rs:+1:10: +1:19
+-         (_2.0: (u8, u8)) = move _3;      // scope 0 at $DIR/issue_67019.rs:+1:10: +1:19
++         (_2.0: (u8, u8)) = const (1_u8, 2_u8); // scope 0 at $DIR/issue_67019.rs:+1:10: +1:19
+          StorageDead(_3);                 // scope 0 at $DIR/issue_67019.rs:+1:18: +1:19
+          _1 = test(move _2) -> bb1;       // scope 0 at $DIR/issue_67019.rs:+1:5: +1:20
                                            // mir::Constant
-                                           // + span: $DIR/issue-67019.rs:12:5: 12:9
+                                           // + span: $DIR/issue_67019.rs:12:5: 12:9
                                            // + literal: Const { ty: fn(((u8, u8),)) {test}, val: Value(<ZST>) }
       }
   
       bb1: {
-          StorageDead(_2);                 // scope 0 at $DIR/issue-67019.rs:+1:19: +1:20
-          StorageDead(_1);                 // scope 0 at $DIR/issue-67019.rs:+1:20: +1:21
-          nop;                             // scope 0 at $DIR/issue-67019.rs:+0:11: +2:2
-          return;                          // scope 0 at $DIR/issue-67019.rs:+2:2: +2:2
+          StorageDead(_2);                 // scope 0 at $DIR/issue_67019.rs:+1:19: +1:20
+          StorageDead(_1);                 // scope 0 at $DIR/issue_67019.rs:+1:20: +1:21
+          nop;                             // scope 0 at $DIR/issue_67019.rs:+0:11: +2:2
+          return;                          // scope 0 at $DIR/issue_67019.rs:+2:2: +2:2
       }
   }
   
diff --git a/src/test/mir-opt/const_prop/issue-67019.rs b/src/test/mir-opt/const_prop/issue_67019.rs
similarity index 100%
rename from src/test/mir-opt/const_prop/issue-67019.rs
rename to src/test/mir-opt/const_prop/issue_67019.rs
diff --git a/src/test/mir-opt/coverage_graphviz.bar.InstrumentCoverage.0.dot b/src/test/mir-opt/coverage_graphviz.bar.InstrumentCoverage.0.dot
index c00eae96e083..03df5c9504be 100644
--- a/src/test/mir-opt/coverage_graphviz.bar.InstrumentCoverage.0.dot
+++ b/src/test/mir-opt/coverage_graphviz.bar.InstrumentCoverage.0.dot
@@ -2,5 +2,5 @@ digraph Cov_0_4 {
     graph [fontname="Courier, monospace"];
     node [fontname="Courier, monospace"];
     edge [fontname="Courier, monospace"];
-    bcb0__Cov_0_4 [shape="none", label=<<table border="0" cellborder="1" cellspacing="0"><tr><td bgcolor="gray" align="center" colspan="1">bcb0</td></tr><tr><td align="left" balign="left"></td></tr><tr><td align="left" balign="left">Counter(bcb0) at 18:1-20:2<br/>    19:5-19:9: @0[0]: Coverage::Counter(1) for $DIR/coverage_graphviz.rs:18:1 - 20:2<br/>    20:2-20:2: @0.Return: return</td></tr><tr><td align="left" balign="left">bb0: Return</td></tr></table>>];
+    bcb0__Cov_0_4 [shape="none", label=<<table border="0" cellborder="1" cellspacing="0"><tr><td bgcolor="gray" align="center" colspan="1">bcb0</td></tr><tr><td align="left" balign="left"></td></tr><tr><td align="left" balign="left">Counter(bcb0) at 18:1-20:2<br align="left"/>    19:5-19:9: @0[0]: Coverage::Counter(1) for $DIR/coverage_graphviz.rs:18:1 - 20:2<br align="left"/>    20:2-20:2: @0.Return: return</td></tr><tr><td align="left" balign="left">bb0: Return</td></tr></table>>];
 }
diff --git a/src/test/mir-opt/coverage_graphviz.main.InstrumentCoverage.0.dot b/src/test/mir-opt/coverage_graphviz.main.InstrumentCoverage.0.dot
index ca0eb7e845aa..fd21b14af25f 100644
--- a/src/test/mir-opt/coverage_graphviz.main.InstrumentCoverage.0.dot
+++ b/src/test/mir-opt/coverage_graphviz.main.InstrumentCoverage.0.dot
@@ -2,10 +2,10 @@ digraph Cov_0_3 {
     graph [fontname="Courier, monospace"];
     node [fontname="Courier, monospace"];
     edge [fontname="Courier, monospace"];
-    bcb3__Cov_0_3 [shape="none", label=<<table border="0" cellborder="1" cellspacing="0"><tr><td bgcolor="gray" align="center" colspan="1">bcb3</td></tr><tr><td align="left" balign="left">Counter(bcb3) at 13:10-13:10<br/>    13:10-13:10: @5[0]: Coverage::Counter(2) for $DIR/coverage_graphviz.rs:13:10 - 13:11</td></tr><tr><td align="left" balign="left">bb5: Goto</td></tr></table>>];
-    bcb2__Cov_0_3 [shape="none", label=<<table border="0" cellborder="1" cellspacing="0"><tr><td bgcolor="gray" align="center" colspan="1">bcb2</td></tr><tr><td align="left" balign="left">Expression(bcb1:(bcb0 + bcb3) - bcb3) at 12:13-12:18<br/>    12:13-12:18: @4[0]: Coverage::Expression(4294967293) = 4294967294 + 0 for $DIR/coverage_graphviz.rs:15:1 - 15:2<br/>Expression(bcb2:(bcb1:(bcb0 + bcb3) - bcb3) + 0) at 15:2-15:2<br/>    15:2-15:2: @4.Return: return</td></tr><tr><td align="left" balign="left">bb4: Return</td></tr></table>>];
-    bcb1__Cov_0_3 [shape="none", label=<<table border="0" cellborder="1" cellspacing="0"><tr><td bgcolor="gray" align="center" colspan="1">bcb1</td></tr><tr><td align="left" balign="left">Expression(bcb0 + bcb3) at 10:5-11:17<br/>    11:12-11:17: @2.Call: _2 = bar() -&gt; [return: bb3, unwind: bb6]</td></tr><tr><td align="left" balign="left">bb1: FalseUnwind<br/>bb2: Call</td></tr><tr><td align="left" balign="left">bb3: SwitchInt</td></tr></table>>];
-    bcb0__Cov_0_3 [shape="none", label=<<table border="0" cellborder="1" cellspacing="0"><tr><td bgcolor="gray" align="center" colspan="1">bcb0</td></tr><tr><td align="left" balign="left"></td></tr><tr><td align="left" balign="left">Counter(bcb0) at 9:1-9:11<br/>    </td></tr><tr><td align="left" balign="left">bb0: Goto</td></tr></table>>];
+    bcb3__Cov_0_3 [shape="none", label=<<table border="0" cellborder="1" cellspacing="0"><tr><td bgcolor="gray" align="center" colspan="1">bcb3</td></tr><tr><td align="left" balign="left">Counter(bcb3) at 13:10-13:10<br align="left"/>    13:10-13:10: @5[0]: Coverage::Counter(2) for $DIR/coverage_graphviz.rs:13:10 - 13:11</td></tr><tr><td align="left" balign="left">bb5: Goto</td></tr></table>>];
+    bcb2__Cov_0_3 [shape="none", label=<<table border="0" cellborder="1" cellspacing="0"><tr><td bgcolor="gray" align="center" colspan="1">bcb2</td></tr><tr><td align="left" balign="left">Expression(bcb1:(bcb0 + bcb3) - bcb3) at 12:13-12:18<br align="left"/>    12:13-12:18: @4[0]: Coverage::Expression(4294967293) = 4294967294 + 0 for $DIR/coverage_graphviz.rs:15:1 - 15:2<br align="left"/>Expression(bcb2:(bcb1:(bcb0 + bcb3) - bcb3) + 0) at 15:2-15:2<br align="left"/>    15:2-15:2: @4.Return: return</td></tr><tr><td align="left" balign="left">bb4: Return</td></tr></table>>];
+    bcb1__Cov_0_3 [shape="none", label=<<table border="0" cellborder="1" cellspacing="0"><tr><td bgcolor="gray" align="center" colspan="1">bcb1</td></tr><tr><td align="left" balign="left">Expression(bcb0 + bcb3) at 10:5-11:17<br align="left"/>    11:12-11:17: @2.Call: _2 = bar() -&gt; [return: bb3, unwind: bb6]</td></tr><tr><td align="left" balign="left">bb1: FalseUnwind<br align="left"/>bb2: Call</td></tr><tr><td align="left" balign="left">bb3: SwitchInt</td></tr></table>>];
+    bcb0__Cov_0_3 [shape="none", label=<<table border="0" cellborder="1" cellspacing="0"><tr><td bgcolor="gray" align="center" colspan="1">bcb0</td></tr><tr><td align="left" balign="left"></td></tr><tr><td align="left" balign="left">Counter(bcb0) at 9:1-9:11<br align="left"/>    </td></tr><tr><td align="left" balign="left">bb0: Goto</td></tr></table>>];
     bcb3__Cov_0_3 -> bcb1__Cov_0_3 [label=<>];
     bcb1__Cov_0_3 -> bcb3__Cov_0_3 [label=<false>];
     bcb1__Cov_0_3 -> bcb2__Cov_0_3 [label=<otherwise>];
diff --git a/src/test/mir-opt/dataflow-const-prop/cast.main.DataflowConstProp.diff b/src/test/mir-opt/dataflow-const-prop/cast.main.DataflowConstProp.diff
new file mode 100644
index 000000000000..bf9ab8669380
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/cast.main.DataflowConstProp.diff
@@ -0,0 +1,37 @@
+- // MIR for `main` before DataflowConstProp
++ // MIR for `main` after DataflowConstProp
+  
+  fn main() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/cast.rs:+0:11: +0:11
+      let _1: i32;                         // in scope 0 at $DIR/cast.rs:+1:9: +1:10
+      let mut _3: u8;                      // in scope 0 at $DIR/cast.rs:+2:13: +2:20
+      let mut _4: i32;                     // in scope 0 at $DIR/cast.rs:+2:13: +2:14
+      scope 1 {
+          debug a => _1;                   // in scope 1 at $DIR/cast.rs:+1:9: +1:10
+          let _2: u8;                      // in scope 1 at $DIR/cast.rs:+2:9: +2:10
+          scope 2 {
+              debug b => _2;               // in scope 2 at $DIR/cast.rs:+2:9: +2:10
+          }
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/cast.rs:+1:9: +1:10
+          _1 = const 257_i32;              // scope 0 at $DIR/cast.rs:+1:13: +1:16
+          StorageLive(_2);                 // scope 1 at $DIR/cast.rs:+2:9: +2:10
+          StorageLive(_3);                 // scope 1 at $DIR/cast.rs:+2:13: +2:20
+          StorageLive(_4);                 // scope 1 at $DIR/cast.rs:+2:13: +2:14
+-         _4 = _1;                         // scope 1 at $DIR/cast.rs:+2:13: +2:14
+-         _3 = move _4 as u8 (IntToInt);   // scope 1 at $DIR/cast.rs:+2:13: +2:20
++         _4 = const 257_i32;              // scope 1 at $DIR/cast.rs:+2:13: +2:14
++         _3 = const 1_u8;                 // scope 1 at $DIR/cast.rs:+2:13: +2:20
+          StorageDead(_4);                 // scope 1 at $DIR/cast.rs:+2:19: +2:20
+-         _2 = Add(move _3, const 1_u8);   // scope 1 at $DIR/cast.rs:+2:13: +2:24
++         _2 = const 2_u8;                 // scope 1 at $DIR/cast.rs:+2:13: +2:24
+          StorageDead(_3);                 // scope 1 at $DIR/cast.rs:+2:23: +2:24
+          _0 = const ();                   // scope 0 at $DIR/cast.rs:+0:11: +3:2
+          StorageDead(_2);                 // scope 1 at $DIR/cast.rs:+3:1: +3:2
+          StorageDead(_1);                 // scope 0 at $DIR/cast.rs:+3:1: +3:2
+          return;                          // scope 0 at $DIR/cast.rs:+3:2: +3:2
+      }
+  }
+  
diff --git a/src/test/mir-opt/dataflow-const-prop/cast.rs b/src/test/mir-opt/dataflow-const-prop/cast.rs
new file mode 100644
index 000000000000..484403f7f0ec
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/cast.rs
@@ -0,0 +1,7 @@
+// unit-test: DataflowConstProp
+
+// EMIT_MIR cast.main.DataflowConstProp.diff
+fn main() {
+    let a = 257;
+    let b = a as u8 + 1;
+}
diff --git a/src/test/mir-opt/dataflow-const-prop/checked.main.DataflowConstProp.diff b/src/test/mir-opt/dataflow-const-prop/checked.main.DataflowConstProp.diff
new file mode 100644
index 000000000000..a4ebd0c8c18f
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/checked.main.DataflowConstProp.diff
@@ -0,0 +1,80 @@
+- // MIR for `main` before DataflowConstProp
++ // MIR for `main` after DataflowConstProp
+  
+  fn main() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/checked.rs:+0:11: +0:11
+      let _1: i32;                         // in scope 0 at $DIR/checked.rs:+1:9: +1:10
+      let mut _4: i32;                     // in scope 0 at $DIR/checked.rs:+3:13: +3:14
+      let mut _5: i32;                     // in scope 0 at $DIR/checked.rs:+3:17: +3:18
+      let mut _6: (i32, bool);             // in scope 0 at $DIR/checked.rs:+3:13: +3:18
+      let mut _9: i32;                     // in scope 0 at $DIR/checked.rs:+6:13: +6:14
+      let mut _10: (i32, bool);            // in scope 0 at $DIR/checked.rs:+6:13: +6:18
+      scope 1 {
+          debug a => _1;                   // in scope 1 at $DIR/checked.rs:+1:9: +1:10
+          let _2: i32;                     // in scope 1 at $DIR/checked.rs:+2:9: +2:10
+          scope 2 {
+              debug b => _2;               // in scope 2 at $DIR/checked.rs:+2:9: +2:10
+              let _3: i32;                 // in scope 2 at $DIR/checked.rs:+3:9: +3:10
+              scope 3 {
+                  debug c => _3;           // in scope 3 at $DIR/checked.rs:+3:9: +3:10
+                  let _7: i32;             // in scope 3 at $DIR/checked.rs:+5:9: +5:10
+                  scope 4 {
+                      debug d => _7;       // in scope 4 at $DIR/checked.rs:+5:9: +5:10
+                      let _8: i32;         // in scope 4 at $DIR/checked.rs:+6:9: +6:10
+                      scope 5 {
+                          debug e => _8;   // in scope 5 at $DIR/checked.rs:+6:9: +6:10
+                      }
+                  }
+              }
+          }
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/checked.rs:+1:9: +1:10
+          _1 = const 1_i32;                // scope 0 at $DIR/checked.rs:+1:13: +1:14
+          StorageLive(_2);                 // scope 1 at $DIR/checked.rs:+2:9: +2:10
+          _2 = const 2_i32;                // scope 1 at $DIR/checked.rs:+2:13: +2:14
+          StorageLive(_3);                 // scope 2 at $DIR/checked.rs:+3:9: +3:10
+          StorageLive(_4);                 // scope 2 at $DIR/checked.rs:+3:13: +3:14
+-         _4 = _1;                         // scope 2 at $DIR/checked.rs:+3:13: +3:14
++         _4 = const 1_i32;                // scope 2 at $DIR/checked.rs:+3:13: +3:14
+          StorageLive(_5);                 // scope 2 at $DIR/checked.rs:+3:17: +3:18
+-         _5 = _2;                         // scope 2 at $DIR/checked.rs:+3:17: +3:18
+-         _6 = CheckedAdd(_4, _5);         // scope 2 at $DIR/checked.rs:+3:13: +3:18
+-         assert(!move (_6.1: bool), "attempt to compute `{} + {}`, which would overflow", move _4, move _5) -> bb1; // scope 2 at $DIR/checked.rs:+3:13: +3:18
++         _5 = const 2_i32;                // scope 2 at $DIR/checked.rs:+3:17: +3:18
++         _6 = CheckedAdd(const 1_i32, const 2_i32); // scope 2 at $DIR/checked.rs:+3:13: +3:18
++         assert(!const false, "attempt to compute `{} + {}`, which would overflow", const 1_i32, const 2_i32) -> bb1; // scope 2 at $DIR/checked.rs:+3:13: +3:18
+      }
+  
+      bb1: {
+-         _3 = move (_6.0: i32);           // scope 2 at $DIR/checked.rs:+3:13: +3:18
++         _3 = const 3_i32;                // scope 2 at $DIR/checked.rs:+3:13: +3:18
+          StorageDead(_5);                 // scope 2 at $DIR/checked.rs:+3:17: +3:18
+          StorageDead(_4);                 // scope 2 at $DIR/checked.rs:+3:17: +3:18
+          StorageLive(_7);                 // scope 3 at $DIR/checked.rs:+5:9: +5:10
+          _7 = const _;                    // scope 3 at $DIR/checked.rs:+5:13: +5:21
+          StorageLive(_8);                 // scope 4 at $DIR/checked.rs:+6:9: +6:10
+          StorageLive(_9);                 // scope 4 at $DIR/checked.rs:+6:13: +6:14
+-         _9 = _7;                         // scope 4 at $DIR/checked.rs:+6:13: +6:14
+-         _10 = CheckedAdd(_9, const 1_i32); // scope 4 at $DIR/checked.rs:+6:13: +6:18
+-         assert(!move (_10.1: bool), "attempt to compute `{} + {}`, which would overflow", move _9, const 1_i32) -> bb2; // scope 4 at $DIR/checked.rs:+6:13: +6:18
++         _9 = const i32::MAX;             // scope 4 at $DIR/checked.rs:+6:13: +6:14
++         _10 = CheckedAdd(const i32::MAX, const 1_i32); // scope 4 at $DIR/checked.rs:+6:13: +6:18
++         assert(!move (_10.1: bool), "attempt to compute `{} + {}`, which would overflow", const i32::MAX, const 1_i32) -> bb2; // scope 4 at $DIR/checked.rs:+6:13: +6:18
+      }
+  
+      bb2: {
+-         _8 = move (_10.0: i32);          // scope 4 at $DIR/checked.rs:+6:13: +6:18
++         _8 = const i32::MIN;             // scope 4 at $DIR/checked.rs:+6:13: +6:18
+          StorageDead(_9);                 // scope 4 at $DIR/checked.rs:+6:17: +6:18
+          _0 = const ();                   // scope 0 at $DIR/checked.rs:+0:11: +7:2
+          StorageDead(_8);                 // scope 4 at $DIR/checked.rs:+7:1: +7:2
+          StorageDead(_7);                 // scope 3 at $DIR/checked.rs:+7:1: +7:2
+          StorageDead(_3);                 // scope 2 at $DIR/checked.rs:+7:1: +7:2
+          StorageDead(_2);                 // scope 1 at $DIR/checked.rs:+7:1: +7:2
+          StorageDead(_1);                 // scope 0 at $DIR/checked.rs:+7:1: +7:2
+          return;                          // scope 0 at $DIR/checked.rs:+7:2: +7:2
+      }
+  }
+  
diff --git a/src/test/mir-opt/dataflow-const-prop/checked.rs b/src/test/mir-opt/dataflow-const-prop/checked.rs
new file mode 100644
index 000000000000..0738a4ee53b8
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/checked.rs
@@ -0,0 +1,13 @@
+// unit-test: DataflowConstProp
+// compile-flags: -Coverflow-checks=on
+
+// EMIT_MIR checked.main.DataflowConstProp.diff
+#[allow(arithmetic_overflow)]
+fn main() {
+    let a = 1;
+    let b = 2;
+    let c = a + b;
+
+    let d = i32::MAX;
+    let e = d + 1;
+}
diff --git a/src/test/mir-opt/dataflow-const-prop/enum.main.DataflowConstProp.diff b/src/test/mir-opt/dataflow-const-prop/enum.main.DataflowConstProp.diff
new file mode 100644
index 000000000000..2ced794e628f
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/enum.main.DataflowConstProp.diff
@@ -0,0 +1,61 @@
+- // MIR for `main` before DataflowConstProp
++ // MIR for `main` after DataflowConstProp
+  
+  fn main() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/enum.rs:+0:11: +0:11
+      let _1: E;                           // in scope 0 at $DIR/enum.rs:+1:9: +1:10
+      let mut _3: isize;                   // in scope 0 at $DIR/enum.rs:+2:23: +2:31
+      scope 1 {
+          debug e => _1;                   // in scope 1 at $DIR/enum.rs:+1:9: +1:10
+          let _2: i32;                     // in scope 1 at $DIR/enum.rs:+2:9: +2:10
+          let _4: i32;                     // in scope 1 at $DIR/enum.rs:+2:29: +2:30
+          let _5: i32;                     // in scope 1 at $DIR/enum.rs:+2:44: +2:45
+          scope 2 {
+              debug x => _2;               // in scope 2 at $DIR/enum.rs:+2:9: +2:10
+          }
+          scope 3 {
+              debug x => _4;               // in scope 3 at $DIR/enum.rs:+2:29: +2:30
+          }
+          scope 4 {
+              debug x => _5;               // in scope 4 at $DIR/enum.rs:+2:44: +2:45
+          }
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/enum.rs:+1:9: +1:10
+          Deinit(_1);                      // scope 0 at $DIR/enum.rs:+1:13: +1:21
+          ((_1 as V1).0: i32) = const 0_i32; // scope 0 at $DIR/enum.rs:+1:13: +1:21
+          discriminant(_1) = 0;            // scope 0 at $DIR/enum.rs:+1:13: +1:21
+          StorageLive(_2);                 // scope 1 at $DIR/enum.rs:+2:9: +2:10
+          _3 = discriminant(_1);           // scope 1 at $DIR/enum.rs:+2:19: +2:20
+          switchInt(move _3) -> [0_isize: bb3, 1_isize: bb1, otherwise: bb2]; // scope 1 at $DIR/enum.rs:+2:13: +2:20
+      }
+  
+      bb1: {
+          StorageLive(_5);                 // scope 1 at $DIR/enum.rs:+2:44: +2:45
+          _5 = ((_1 as V2).0: i32);        // scope 1 at $DIR/enum.rs:+2:44: +2:45
+          _2 = _5;                         // scope 4 at $DIR/enum.rs:+2:50: +2:51
+          StorageDead(_5);                 // scope 1 at $DIR/enum.rs:+2:50: +2:51
+          goto -> bb4;                     // scope 1 at $DIR/enum.rs:+2:50: +2:51
+      }
+  
+      bb2: {
+          unreachable;                     // scope 1 at $DIR/enum.rs:+2:19: +2:20
+      }
+  
+      bb3: {
+          StorageLive(_4);                 // scope 1 at $DIR/enum.rs:+2:29: +2:30
+          _4 = ((_1 as V1).0: i32);        // scope 1 at $DIR/enum.rs:+2:29: +2:30
+          _2 = _4;                         // scope 3 at $DIR/enum.rs:+2:35: +2:36
+          StorageDead(_4);                 // scope 1 at $DIR/enum.rs:+2:35: +2:36
+          goto -> bb4;                     // scope 1 at $DIR/enum.rs:+2:35: +2:36
+      }
+  
+      bb4: {
+          _0 = const ();                   // scope 0 at $DIR/enum.rs:+0:11: +3:2
+          StorageDead(_2);                 // scope 1 at $DIR/enum.rs:+3:1: +3:2
+          StorageDead(_1);                 // scope 0 at $DIR/enum.rs:+3:1: +3:2
+          return;                          // scope 0 at $DIR/enum.rs:+3:2: +3:2
+      }
+  }
+  
diff --git a/src/test/mir-opt/dataflow-const-prop/enum.rs b/src/test/mir-opt/dataflow-const-prop/enum.rs
new file mode 100644
index 000000000000..13288577dea3
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/enum.rs
@@ -0,0 +1,13 @@
+// unit-test: DataflowConstProp
+
+// Not trackable, because variants could be aliased.
+enum E {
+    V1(i32),
+    V2(i32)
+}
+
+// EMIT_MIR enum.main.DataflowConstProp.diff
+fn main() {
+    let e = E::V1(0);
+    let x = match e { E::V1(x) => x, E::V2(x) => x };
+}
diff --git a/src/test/mir-opt/dataflow-const-prop/if.main.DataflowConstProp.diff b/src/test/mir-opt/dataflow-const-prop/if.main.DataflowConstProp.diff
new file mode 100644
index 000000000000..26808c70fbf2
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/if.main.DataflowConstProp.diff
@@ -0,0 +1,112 @@
+- // MIR for `main` before DataflowConstProp
++ // MIR for `main` after DataflowConstProp
+  
+  fn main() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/if.rs:+0:11: +0:11
+      let _1: i32;                         // in scope 0 at $DIR/if.rs:+1:9: +1:10
+      let mut _3: bool;                    // in scope 0 at $DIR/if.rs:+2:16: +2:22
+      let mut _4: i32;                     // in scope 0 at $DIR/if.rs:+2:16: +2:17
+      let mut _6: i32;                     // in scope 0 at $DIR/if.rs:+3:13: +3:14
+      let mut _8: bool;                    // in scope 0 at $DIR/if.rs:+5:16: +5:22
+      let mut _9: i32;                     // in scope 0 at $DIR/if.rs:+5:16: +5:17
+      let mut _10: i32;                    // in scope 0 at $DIR/if.rs:+5:36: +5:37
+      let mut _12: i32;                    // in scope 0 at $DIR/if.rs:+6:13: +6:14
+      scope 1 {
+          debug a => _1;                   // in scope 1 at $DIR/if.rs:+1:9: +1:10
+          let _2: i32;                     // in scope 1 at $DIR/if.rs:+2:9: +2:10
+          scope 2 {
+              debug b => _2;               // in scope 2 at $DIR/if.rs:+2:9: +2:10
+              let _5: i32;                 // in scope 2 at $DIR/if.rs:+3:9: +3:10
+              scope 3 {
+                  debug c => _5;           // in scope 3 at $DIR/if.rs:+3:9: +3:10
+                  let _7: i32;             // in scope 3 at $DIR/if.rs:+5:9: +5:10
+                  scope 4 {
+                      debug d => _7;       // in scope 4 at $DIR/if.rs:+5:9: +5:10
+                      let _11: i32;        // in scope 4 at $DIR/if.rs:+6:9: +6:10
+                      scope 5 {
+                          debug e => _11;  // in scope 5 at $DIR/if.rs:+6:9: +6:10
+                      }
+                  }
+              }
+          }
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/if.rs:+1:9: +1:10
+          _1 = const 1_i32;                // scope 0 at $DIR/if.rs:+1:13: +1:14
+          StorageLive(_2);                 // scope 1 at $DIR/if.rs:+2:9: +2:10
+          StorageLive(_3);                 // scope 1 at $DIR/if.rs:+2:16: +2:22
+          StorageLive(_4);                 // scope 1 at $DIR/if.rs:+2:16: +2:17
+-         _4 = _1;                         // scope 1 at $DIR/if.rs:+2:16: +2:17
+-         _3 = Eq(move _4, const 1_i32);   // scope 1 at $DIR/if.rs:+2:16: +2:22
++         _4 = const 1_i32;                // scope 1 at $DIR/if.rs:+2:16: +2:17
++         _3 = const true;                 // scope 1 at $DIR/if.rs:+2:16: +2:22
+          StorageDead(_4);                 // scope 1 at $DIR/if.rs:+2:21: +2:22
+-         switchInt(move _3) -> [false: bb2, otherwise: bb1]; // scope 1 at $DIR/if.rs:+2:16: +2:22
++         switchInt(const true) -> [false: bb2, otherwise: bb1]; // scope 1 at $DIR/if.rs:+2:16: +2:22
+      }
+  
+      bb1: {
+          _2 = const 2_i32;                // scope 1 at $DIR/if.rs:+2:25: +2:26
+          goto -> bb3;                     // scope 1 at $DIR/if.rs:+2:13: +2:39
+      }
+  
+      bb2: {
+          _2 = const 3_i32;                // scope 1 at $DIR/if.rs:+2:36: +2:37
+          goto -> bb3;                     // scope 1 at $DIR/if.rs:+2:13: +2:39
+      }
+  
+      bb3: {
+          StorageDead(_3);                 // scope 1 at $DIR/if.rs:+2:38: +2:39
+          StorageLive(_5);                 // scope 2 at $DIR/if.rs:+3:9: +3:10
+          StorageLive(_6);                 // scope 2 at $DIR/if.rs:+3:13: +3:14
+-         _6 = _2;                         // scope 2 at $DIR/if.rs:+3:13: +3:14
+-         _5 = Add(move _6, const 1_i32);  // scope 2 at $DIR/if.rs:+3:13: +3:18
++         _6 = const 2_i32;                // scope 2 at $DIR/if.rs:+3:13: +3:14
++         _5 = const 3_i32;                // scope 2 at $DIR/if.rs:+3:13: +3:18
+          StorageDead(_6);                 // scope 2 at $DIR/if.rs:+3:17: +3:18
+          StorageLive(_7);                 // scope 3 at $DIR/if.rs:+5:9: +5:10
+          StorageLive(_8);                 // scope 3 at $DIR/if.rs:+5:16: +5:22
+          StorageLive(_9);                 // scope 3 at $DIR/if.rs:+5:16: +5:17
+-         _9 = _1;                         // scope 3 at $DIR/if.rs:+5:16: +5:17
+-         _8 = Eq(move _9, const 1_i32);   // scope 3 at $DIR/if.rs:+5:16: +5:22
++         _9 = const 1_i32;                // scope 3 at $DIR/if.rs:+5:16: +5:17
++         _8 = const true;                 // scope 3 at $DIR/if.rs:+5:16: +5:22
+          StorageDead(_9);                 // scope 3 at $DIR/if.rs:+5:21: +5:22
+-         switchInt(move _8) -> [false: bb5, otherwise: bb4]; // scope 3 at $DIR/if.rs:+5:16: +5:22
++         switchInt(const true) -> [false: bb5, otherwise: bb4]; // scope 3 at $DIR/if.rs:+5:16: +5:22
+      }
+  
+      bb4: {
+-         _7 = _1;                         // scope 3 at $DIR/if.rs:+5:25: +5:26
++         _7 = const 1_i32;                // scope 3 at $DIR/if.rs:+5:25: +5:26
+          goto -> bb6;                     // scope 3 at $DIR/if.rs:+5:13: +5:43
+      }
+  
+      bb5: {
+          StorageLive(_10);                // scope 3 at $DIR/if.rs:+5:36: +5:37
+          _10 = _1;                        // scope 3 at $DIR/if.rs:+5:36: +5:37
+          _7 = Add(move _10, const 1_i32); // scope 3 at $DIR/if.rs:+5:36: +5:41
+          StorageDead(_10);                // scope 3 at $DIR/if.rs:+5:40: +5:41
+          goto -> bb6;                     // scope 3 at $DIR/if.rs:+5:13: +5:43
+      }
+  
+      bb6: {
+          StorageDead(_8);                 // scope 3 at $DIR/if.rs:+5:42: +5:43
+          StorageLive(_11);                // scope 4 at $DIR/if.rs:+6:9: +6:10
+          StorageLive(_12);                // scope 4 at $DIR/if.rs:+6:13: +6:14
+-         _12 = _7;                        // scope 4 at $DIR/if.rs:+6:13: +6:14
+-         _11 = Add(move _12, const 1_i32); // scope 4 at $DIR/if.rs:+6:13: +6:18
++         _12 = const 1_i32;               // scope 4 at $DIR/if.rs:+6:13: +6:14
++         _11 = const 2_i32;               // scope 4 at $DIR/if.rs:+6:13: +6:18
+          StorageDead(_12);                // scope 4 at $DIR/if.rs:+6:17: +6:18
+          _0 = const ();                   // scope 0 at $DIR/if.rs:+0:11: +7:2
+          StorageDead(_11);                // scope 4 at $DIR/if.rs:+7:1: +7:2
+          StorageDead(_7);                 // scope 3 at $DIR/if.rs:+7:1: +7:2
+          StorageDead(_5);                 // scope 2 at $DIR/if.rs:+7:1: +7:2
+          StorageDead(_2);                 // scope 1 at $DIR/if.rs:+7:1: +7:2
+          StorageDead(_1);                 // scope 0 at $DIR/if.rs:+7:1: +7:2
+          return;                          // scope 0 at $DIR/if.rs:+7:2: +7:2
+      }
+  }
+  
diff --git a/src/test/mir-opt/dataflow-const-prop/if.rs b/src/test/mir-opt/dataflow-const-prop/if.rs
new file mode 100644
index 000000000000..34fc35790c17
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/if.rs
@@ -0,0 +1,11 @@
+// unit-test: DataflowConstProp
+
+// EMIT_MIR if.main.DataflowConstProp.diff
+fn main() {
+    let a = 1;
+    let b = if a == 1 { 2 } else { 3 };
+    let c = b + 1;
+
+    let d = if a == 1 { a } else { a + 1 };
+    let e = d + 1;
+}
diff --git a/src/test/mir-opt/dataflow-const-prop/inherit_overflow.main.DataflowConstProp.diff b/src/test/mir-opt/dataflow-const-prop/inherit_overflow.main.DataflowConstProp.diff
new file mode 100644
index 000000000000..bf4557ed3d92
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/inherit_overflow.main.DataflowConstProp.diff
@@ -0,0 +1,45 @@
+- // MIR for `main` before DataflowConstProp
++ // MIR for `main` after DataflowConstProp
+  
+  fn main() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/inherit_overflow.rs:+0:11: +0:11
+      let mut _1: u8;                      // in scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+      let mut _2: u8;                      // in scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+      let mut _3: u8;                      // in scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+      scope 1 {
+      }
+      scope 2 (inlined <u8 as Add>::add) { // at $DIR/inherit_overflow.rs:7:13: 7:47
+          debug self => _2;                // in scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+          debug other => _3;               // in scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+          let mut _4: u8;                  // in scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+          let mut _5: u8;                  // in scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+          let mut _6: (u8, bool);          // in scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+          StorageLive(_2);                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+          _2 = const u8::MAX;              // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+          StorageLive(_3);                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+          _3 = const 1_u8;                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+          StorageLive(_4);                 // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+          _4 = const u8::MAX;              // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+          StorageLive(_5);                 // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+          _5 = const 1_u8;                 // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+          _6 = CheckedAdd(const u8::MAX, const 1_u8); // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+          assert(!move (_6.1: bool), "attempt to compute `{} + {}`, which would overflow", const u8::MAX, const 1_u8) -> bb1; // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+      }
+  
+      bb1: {
+-         _1 = move (_6.0: u8);            // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
++         _1 = const 0_u8;                 // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+          StorageDead(_5);                 // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+          StorageDead(_4);                 // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+          StorageDead(_3);                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+          StorageDead(_2);                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+          StorageDead(_1);                 // scope 0 at $DIR/inherit_overflow.rs:+3:47: +3:48
+          nop;                             // scope 0 at $DIR/inherit_overflow.rs:+0:11: +4:2
+          return;                          // scope 0 at $DIR/inherit_overflow.rs:+4:2: +4:2
+      }
+  }
+  
diff --git a/src/test/mir-opt/dataflow-const-prop/inherit_overflow.rs b/src/test/mir-opt/dataflow-const-prop/inherit_overflow.rs
new file mode 100644
index 000000000000..2f2d9d0102d1
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/inherit_overflow.rs
@@ -0,0 +1,8 @@
+// compile-flags: -Zunsound-mir-opts
+
+// EMIT_MIR inherit_overflow.main.DataflowConstProp.diff
+fn main() {
+    // After inlining, this will contain a `CheckedBinaryOp`. The overflow
+    // must be ignored by the constant propagation to avoid triggering a panic.
+    let _ = <u8 as std::ops::Add>::add(255, 1);
+}
diff --git a/src/test/mir-opt/dataflow-const-prop/issue_81605.f.DataflowConstProp.diff b/src/test/mir-opt/dataflow-const-prop/issue_81605.f.DataflowConstProp.diff
new file mode 100644
index 000000000000..881d80f7c032
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/issue_81605.f.DataflowConstProp.diff
@@ -0,0 +1,35 @@
+- // MIR for `f` before DataflowConstProp
++ // MIR for `f` after DataflowConstProp
+  
+  fn f() -> usize {
+      let mut _0: usize;                   // return place in scope 0 at $DIR/issue_81605.rs:+0:11: +0:16
+      let mut _1: usize;                   // in scope 0 at $DIR/issue_81605.rs:+1:9: +1:33
+      let mut _2: bool;                    // in scope 0 at $DIR/issue_81605.rs:+1:12: +1:16
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/issue_81605.rs:+1:9: +1:33
+          StorageLive(_2);                 // scope 0 at $DIR/issue_81605.rs:+1:12: +1:16
+          _2 = const true;                 // scope 0 at $DIR/issue_81605.rs:+1:12: +1:16
+-         switchInt(move _2) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/issue_81605.rs:+1:12: +1:16
++         switchInt(const true) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/issue_81605.rs:+1:12: +1:16
+      }
+  
+      bb1: {
+          _1 = const 1_usize;              // scope 0 at $DIR/issue_81605.rs:+1:19: +1:20
+          goto -> bb3;                     // scope 0 at $DIR/issue_81605.rs:+1:9: +1:33
+      }
+  
+      bb2: {
+          _1 = const 2_usize;              // scope 0 at $DIR/issue_81605.rs:+1:30: +1:31
+          goto -> bb3;                     // scope 0 at $DIR/issue_81605.rs:+1:9: +1:33
+      }
+  
+      bb3: {
+          StorageDead(_2);                 // scope 0 at $DIR/issue_81605.rs:+1:32: +1:33
+-         _0 = Add(const 1_usize, move _1); // scope 0 at $DIR/issue_81605.rs:+1:5: +1:33
++         _0 = const 2_usize;              // scope 0 at $DIR/issue_81605.rs:+1:5: +1:33
+          StorageDead(_1);                 // scope 0 at $DIR/issue_81605.rs:+1:32: +1:33
+          return;                          // scope 0 at $DIR/issue_81605.rs:+2:2: +2:2
+      }
+  }
+  
diff --git a/src/test/mir-opt/dataflow-const-prop/issue_81605.rs b/src/test/mir-opt/dataflow-const-prop/issue_81605.rs
new file mode 100644
index 000000000000..d75e2a28bef6
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/issue_81605.rs
@@ -0,0 +1,10 @@
+// unit-test: DataflowConstProp
+
+// EMIT_MIR issue_81605.f.DataflowConstProp.diff
+fn f() -> usize {
+    1 + if true { 1 } else { 2 }
+}
+
+fn main() {
+    f();
+}
diff --git a/src/test/mir-opt/dataflow-const-prop/ref_without_sb.main.DataflowConstProp.diff b/src/test/mir-opt/dataflow-const-prop/ref_without_sb.main.DataflowConstProp.diff
new file mode 100644
index 000000000000..158f187f1576
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/ref_without_sb.main.DataflowConstProp.diff
@@ -0,0 +1,55 @@
+- // MIR for `main` before DataflowConstProp
++ // MIR for `main` after DataflowConstProp
+  
+  fn main() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/ref_without_sb.rs:+0:11: +0:11
+      let mut _1: i32;                     // in scope 0 at $DIR/ref_without_sb.rs:+1:9: +1:14
+      let _2: ();                          // in scope 0 at $DIR/ref_without_sb.rs:+2:5: +2:15
+      let mut _3: &i32;                    // in scope 0 at $DIR/ref_without_sb.rs:+2:12: +2:14
+      let _4: &i32;                        // in scope 0 at $DIR/ref_without_sb.rs:+2:12: +2:14
+      let _5: ();                          // in scope 0 at $DIR/ref_without_sb.rs:+4:5: +4:20
+      scope 1 {
+          debug a => _1;                   // in scope 1 at $DIR/ref_without_sb.rs:+1:9: +1:14
+          let _6: i32;                     // in scope 1 at $DIR/ref_without_sb.rs:+6:9: +6:10
+          scope 2 {
+              debug b => _6;               // in scope 2 at $DIR/ref_without_sb.rs:+6:9: +6:10
+          }
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/ref_without_sb.rs:+1:9: +1:14
+          _1 = const 0_i32;                // scope 0 at $DIR/ref_without_sb.rs:+1:17: +1:18
+          StorageLive(_2);                 // scope 1 at $DIR/ref_without_sb.rs:+2:5: +2:15
+          StorageLive(_3);                 // scope 1 at $DIR/ref_without_sb.rs:+2:12: +2:14
+          StorageLive(_4);                 // scope 1 at $DIR/ref_without_sb.rs:+2:12: +2:14
+          _4 = &_1;                        // scope 1 at $DIR/ref_without_sb.rs:+2:12: +2:14
+          _3 = &(*_4);                     // scope 1 at $DIR/ref_without_sb.rs:+2:12: +2:14
+          _2 = escape::<i32>(move _3) -> bb1; // scope 1 at $DIR/ref_without_sb.rs:+2:5: +2:15
+                                           // mir::Constant
+                                           // + span: $DIR/ref_without_sb.rs:12:5: 12:11
+                                           // + literal: Const { ty: for<'a> fn(&'a i32) {escape::<i32>}, val: Value(<ZST>) }
+      }
+  
+      bb1: {
+          StorageDead(_3);                 // scope 1 at $DIR/ref_without_sb.rs:+2:14: +2:15
+          StorageDead(_4);                 // scope 1 at $DIR/ref_without_sb.rs:+2:15: +2:16
+          StorageDead(_2);                 // scope 1 at $DIR/ref_without_sb.rs:+2:15: +2:16
+          _1 = const 1_i32;                // scope 1 at $DIR/ref_without_sb.rs:+3:5: +3:10
+          StorageLive(_5);                 // scope 1 at $DIR/ref_without_sb.rs:+4:5: +4:20
+          _5 = some_function() -> bb2;     // scope 1 at $DIR/ref_without_sb.rs:+4:5: +4:20
+                                           // mir::Constant
+                                           // + span: $DIR/ref_without_sb.rs:14:5: 14:18
+                                           // + literal: Const { ty: fn() {some_function}, val: Value(<ZST>) }
+      }
+  
+      bb2: {
+          StorageDead(_5);                 // scope 1 at $DIR/ref_without_sb.rs:+4:20: +4:21
+          StorageLive(_6);                 // scope 1 at $DIR/ref_without_sb.rs:+6:9: +6:10
+          _6 = _1;                         // scope 1 at $DIR/ref_without_sb.rs:+6:13: +6:14
+          _0 = const ();                   // scope 0 at $DIR/ref_without_sb.rs:+0:11: +7:2
+          StorageDead(_6);                 // scope 1 at $DIR/ref_without_sb.rs:+7:1: +7:2
+          StorageDead(_1);                 // scope 0 at $DIR/ref_without_sb.rs:+7:1: +7:2
+          return;                          // scope 0 at $DIR/ref_without_sb.rs:+7:2: +7:2
+      }
+  }
+  
diff --git a/src/test/mir-opt/dataflow-const-prop/ref_without_sb.rs b/src/test/mir-opt/dataflow-const-prop/ref_without_sb.rs
new file mode 100644
index 000000000000..2fd480b0968a
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/ref_without_sb.rs
@@ -0,0 +1,17 @@
+// unit-test: DataflowConstProp
+
+#[inline(never)]
+fn escape<T>(x: &T) {}
+
+#[inline(never)]
+fn some_function() {}
+
+// EMIT_MIR ref_without_sb.main.DataflowConstProp.diff
+fn main() {
+    let mut a = 0;
+    escape(&a);
+    a = 1;
+    some_function();
+    // This should currently not be propagated.
+    let b = a;
+}
diff --git a/src/test/mir-opt/dataflow-const-prop/repr_transparent.main.DataflowConstProp.diff b/src/test/mir-opt/dataflow-const-prop/repr_transparent.main.DataflowConstProp.diff
new file mode 100644
index 000000000000..f66b00a9a224
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/repr_transparent.main.DataflowConstProp.diff
@@ -0,0 +1,44 @@
+- // MIR for `main` before DataflowConstProp
++ // MIR for `main` after DataflowConstProp
+  
+  fn main() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/repr_transparent.rs:+0:11: +0:11
+      let _1: I32;                         // in scope 0 at $DIR/repr_transparent.rs:+1:9: +1:10
+      let mut _3: i32;                     // in scope 0 at $DIR/repr_transparent.rs:+2:17: +2:26
+      let mut _4: i32;                     // in scope 0 at $DIR/repr_transparent.rs:+2:17: +2:20
+      let mut _5: i32;                     // in scope 0 at $DIR/repr_transparent.rs:+2:23: +2:26
+      scope 1 {
+          debug x => _1;                   // in scope 1 at $DIR/repr_transparent.rs:+1:9: +1:10
+          let _2: I32;                     // in scope 1 at $DIR/repr_transparent.rs:+2:9: +2:10
+          scope 2 {
+              debug y => _2;               // in scope 2 at $DIR/repr_transparent.rs:+2:9: +2:10
+          }
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/repr_transparent.rs:+1:9: +1:10
+          Deinit(_1);                      // scope 0 at $DIR/repr_transparent.rs:+1:13: +1:19
+          (_1.0: i32) = const 0_i32;       // scope 0 at $DIR/repr_transparent.rs:+1:13: +1:19
+          StorageLive(_2);                 // scope 1 at $DIR/repr_transparent.rs:+2:9: +2:10
+          StorageLive(_3);                 // scope 1 at $DIR/repr_transparent.rs:+2:17: +2:26
+          StorageLive(_4);                 // scope 1 at $DIR/repr_transparent.rs:+2:17: +2:20
+-         _4 = (_1.0: i32);                // scope 1 at $DIR/repr_transparent.rs:+2:17: +2:20
++         _4 = const 0_i32;                // scope 1 at $DIR/repr_transparent.rs:+2:17: +2:20
+          StorageLive(_5);                 // scope 1 at $DIR/repr_transparent.rs:+2:23: +2:26
+-         _5 = (_1.0: i32);                // scope 1 at $DIR/repr_transparent.rs:+2:23: +2:26
+-         _3 = Add(move _4, move _5);      // scope 1 at $DIR/repr_transparent.rs:+2:17: +2:26
++         _5 = const 0_i32;                // scope 1 at $DIR/repr_transparent.rs:+2:23: +2:26
++         _3 = const 0_i32;                // scope 1 at $DIR/repr_transparent.rs:+2:17: +2:26
+          StorageDead(_5);                 // scope 1 at $DIR/repr_transparent.rs:+2:25: +2:26
+          StorageDead(_4);                 // scope 1 at $DIR/repr_transparent.rs:+2:25: +2:26
+          Deinit(_2);                      // scope 1 at $DIR/repr_transparent.rs:+2:13: +2:27
+-         (_2.0: i32) = move _3;           // scope 1 at $DIR/repr_transparent.rs:+2:13: +2:27
++         (_2.0: i32) = const 0_i32;       // scope 1 at $DIR/repr_transparent.rs:+2:13: +2:27
+          StorageDead(_3);                 // scope 1 at $DIR/repr_transparent.rs:+2:26: +2:27
+          _0 = const ();                   // scope 0 at $DIR/repr_transparent.rs:+0:11: +3:2
+          StorageDead(_2);                 // scope 1 at $DIR/repr_transparent.rs:+3:1: +3:2
+          StorageDead(_1);                 // scope 0 at $DIR/repr_transparent.rs:+3:1: +3:2
+          return;                          // scope 0 at $DIR/repr_transparent.rs:+3:2: +3:2
+      }
+  }
+  
diff --git a/src/test/mir-opt/dataflow-const-prop/repr_transparent.rs b/src/test/mir-opt/dataflow-const-prop/repr_transparent.rs
new file mode 100644
index 000000000000..4ce0ca4dff46
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/repr_transparent.rs
@@ -0,0 +1,12 @@
+// unit-test: DataflowConstProp
+
+// The struct has scalar ABI, but is not a scalar type.
+// Make sure that we handle this correctly.
+#[repr(transparent)]
+struct I32(i32);
+
+// EMIT_MIR repr_transparent.main.DataflowConstProp.diff
+fn main() {
+    let x = I32(0);
+    let y = I32(x.0 + x.0);
+}
diff --git a/src/test/mir-opt/dataflow-const-prop/self_assign.main.DataflowConstProp.diff b/src/test/mir-opt/dataflow-const-prop/self_assign.main.DataflowConstProp.diff
new file mode 100644
index 000000000000..df08eff94cb2
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/self_assign.main.DataflowConstProp.diff
@@ -0,0 +1,46 @@
+- // MIR for `main` before DataflowConstProp
++ // MIR for `main` after DataflowConstProp
+  
+  fn main() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/self_assign.rs:+0:11: +0:11
+      let mut _1: i32;                     // in scope 0 at $DIR/self_assign.rs:+1:9: +1:14
+      let mut _2: i32;                     // in scope 0 at $DIR/self_assign.rs:+2:9: +2:10
+      let mut _3: i32;                     // in scope 0 at $DIR/self_assign.rs:+3:9: +3:10
+      let mut _5: &i32;                    // in scope 0 at $DIR/self_assign.rs:+6:9: +6:10
+      let mut _6: i32;                     // in scope 0 at $DIR/self_assign.rs:+7:9: +7:11
+      scope 1 {
+          debug a => _1;                   // in scope 1 at $DIR/self_assign.rs:+1:9: +1:14
+          let mut _4: &i32;                // in scope 1 at $DIR/self_assign.rs:+5:9: +5:14
+          scope 2 {
+              debug b => _4;               // in scope 2 at $DIR/self_assign.rs:+5:9: +5:14
+          }
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/self_assign.rs:+1:9: +1:14
+          _1 = const 0_i32;                // scope 0 at $DIR/self_assign.rs:+1:17: +1:18
+          StorageLive(_2);                 // scope 1 at $DIR/self_assign.rs:+2:9: +2:10
+          _2 = _1;                         // scope 1 at $DIR/self_assign.rs:+2:9: +2:10
+          _1 = Add(move _2, const 1_i32);  // scope 1 at $DIR/self_assign.rs:+2:5: +2:14
+          StorageDead(_2);                 // scope 1 at $DIR/self_assign.rs:+2:13: +2:14
+          StorageLive(_3);                 // scope 1 at $DIR/self_assign.rs:+3:9: +3:10
+          _3 = _1;                         // scope 1 at $DIR/self_assign.rs:+3:9: +3:10
+          _1 = move _3;                    // scope 1 at $DIR/self_assign.rs:+3:5: +3:10
+          StorageDead(_3);                 // scope 1 at $DIR/self_assign.rs:+3:9: +3:10
+          StorageLive(_4);                 // scope 1 at $DIR/self_assign.rs:+5:9: +5:14
+          _4 = &_1;                        // scope 1 at $DIR/self_assign.rs:+5:17: +5:19
+          StorageLive(_5);                 // scope 2 at $DIR/self_assign.rs:+6:9: +6:10
+          _5 = _4;                         // scope 2 at $DIR/self_assign.rs:+6:9: +6:10
+          _4 = move _5;                    // scope 2 at $DIR/self_assign.rs:+6:5: +6:10
+          StorageDead(_5);                 // scope 2 at $DIR/self_assign.rs:+6:9: +6:10
+          StorageLive(_6);                 // scope 2 at $DIR/self_assign.rs:+7:9: +7:11
+          _6 = (*_4);                      // scope 2 at $DIR/self_assign.rs:+7:9: +7:11
+          _1 = move _6;                    // scope 2 at $DIR/self_assign.rs:+7:5: +7:11
+          StorageDead(_6);                 // scope 2 at $DIR/self_assign.rs:+7:10: +7:11
+          _0 = const ();                   // scope 0 at $DIR/self_assign.rs:+0:11: +8:2
+          StorageDead(_4);                 // scope 1 at $DIR/self_assign.rs:+8:1: +8:2
+          StorageDead(_1);                 // scope 0 at $DIR/self_assign.rs:+8:1: +8:2
+          return;                          // scope 0 at $DIR/self_assign.rs:+8:2: +8:2
+      }
+  }
+  
diff --git a/src/test/mir-opt/dataflow-const-prop/self_assign.rs b/src/test/mir-opt/dataflow-const-prop/self_assign.rs
new file mode 100644
index 000000000000..8de2195f93ba
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/self_assign.rs
@@ -0,0 +1,12 @@
+// unit-test: DataflowConstProp
+
+// EMIT_MIR self_assign.main.DataflowConstProp.diff
+fn main() {
+    let mut a = 0;
+    a = a + 1;
+    a = a;
+
+    let mut b = &a;
+    b = b;
+    a = *b;
+}
diff --git a/src/test/mir-opt/dataflow-const-prop/self_assign_add.main.DataflowConstProp.diff b/src/test/mir-opt/dataflow-const-prop/self_assign_add.main.DataflowConstProp.diff
new file mode 100644
index 000000000000..c09e4061eded
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/self_assign_add.main.DataflowConstProp.diff
@@ -0,0 +1,23 @@
+- // MIR for `main` before DataflowConstProp
++ // MIR for `main` after DataflowConstProp
+  
+  fn main() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/self_assign_add.rs:+0:11: +0:11
+      let mut _1: i32;                     // in scope 0 at $DIR/self_assign_add.rs:+1:9: +1:14
+      scope 1 {
+          debug a => _1;                   // in scope 1 at $DIR/self_assign_add.rs:+1:9: +1:14
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/self_assign_add.rs:+1:9: +1:14
+          _1 = const 0_i32;                // scope 0 at $DIR/self_assign_add.rs:+1:17: +1:18
+-         _1 = Add(_1, const 1_i32);       // scope 1 at $DIR/self_assign_add.rs:+2:5: +2:11
+-         _1 = Add(_1, const 1_i32);       // scope 1 at $DIR/self_assign_add.rs:+3:5: +3:11
++         _1 = const 1_i32;                // scope 1 at $DIR/self_assign_add.rs:+2:5: +2:11
++         _1 = const 2_i32;                // scope 1 at $DIR/self_assign_add.rs:+3:5: +3:11
+          _0 = const ();                   // scope 0 at $DIR/self_assign_add.rs:+0:11: +4:2
+          StorageDead(_1);                 // scope 0 at $DIR/self_assign_add.rs:+4:1: +4:2
+          return;                          // scope 0 at $DIR/self_assign_add.rs:+4:2: +4:2
+      }
+  }
+  
diff --git a/src/test/mir-opt/dataflow-const-prop/self_assign_add.rs b/src/test/mir-opt/dataflow-const-prop/self_assign_add.rs
new file mode 100644
index 000000000000..e3282762459a
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/self_assign_add.rs
@@ -0,0 +1,8 @@
+// unit-test: DataflowConstProp
+
+// EMIT_MIR self_assign_add.main.DataflowConstProp.diff
+fn main() {
+    let mut a = 0;
+    a += 1;
+    a += 1;
+}
diff --git a/src/test/mir-opt/dataflow-const-prop/sibling_ptr.main.DataflowConstProp.diff b/src/test/mir-opt/dataflow-const-prop/sibling_ptr.main.DataflowConstProp.diff
new file mode 100644
index 000000000000..8126d4b8585e
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/sibling_ptr.main.DataflowConstProp.diff
@@ -0,0 +1,56 @@
+- // MIR for `main` before DataflowConstProp
++ // MIR for `main` after DataflowConstProp
+  
+  fn main() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/sibling_ptr.rs:+0:11: +0:11
+      let mut _1: (u8, u8);                // in scope 0 at $DIR/sibling_ptr.rs:+1:9: +1:14
+      let _2: ();                          // in scope 0 at $DIR/sibling_ptr.rs:+2:5: +5:6
+      let mut _4: *mut u8;                 // in scope 0 at $DIR/sibling_ptr.rs:+4:10: +4:18
+      let mut _5: *mut u8;                 // in scope 0 at $DIR/sibling_ptr.rs:+4:10: +4:11
+      scope 1 {
+          debug x => _1;                   // in scope 1 at $DIR/sibling_ptr.rs:+1:9: +1:14
+          let _6: u8;                      // in scope 1 at $DIR/sibling_ptr.rs:+6:9: +6:11
+          scope 2 {
+              let _3: *mut u8;             // in scope 2 at $DIR/sibling_ptr.rs:+3:13: +3:14
+              scope 3 {
+                  debug p => _3;           // in scope 3 at $DIR/sibling_ptr.rs:+3:13: +3:14
+              }
+          }
+          scope 4 {
+              debug x1 => _6;              // in scope 4 at $DIR/sibling_ptr.rs:+6:9: +6:11
+          }
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/sibling_ptr.rs:+1:9: +1:14
+          Deinit(_1);                      // scope 0 at $DIR/sibling_ptr.rs:+1:27: +1:33
+          (_1.0: u8) = const 0_u8;         // scope 0 at $DIR/sibling_ptr.rs:+1:27: +1:33
+          (_1.1: u8) = const 0_u8;         // scope 0 at $DIR/sibling_ptr.rs:+1:27: +1:33
+          StorageLive(_2);                 // scope 1 at $DIR/sibling_ptr.rs:+2:5: +5:6
+          StorageLive(_3);                 // scope 2 at $DIR/sibling_ptr.rs:+3:13: +3:14
+          _3 = &raw mut (_1.0: u8);        // scope 2 at $SRC_DIR/core/src/ptr/mod.rs:LL:COL
+          StorageLive(_4);                 // scope 3 at $DIR/sibling_ptr.rs:+4:10: +4:18
+          StorageLive(_5);                 // scope 3 at $DIR/sibling_ptr.rs:+4:10: +4:11
+          _5 = _3;                         // scope 3 at $DIR/sibling_ptr.rs:+4:10: +4:11
+          _4 = ptr::mut_ptr::<impl *mut u8>::add(move _5, const 1_usize) -> bb1; // scope 3 at $DIR/sibling_ptr.rs:+4:10: +4:18
+                                           // mir::Constant
+                                           // + span: $DIR/sibling_ptr.rs:8:12: 8:15
+                                           // + literal: Const { ty: unsafe fn(*mut u8, usize) -> *mut u8 {ptr::mut_ptr::<impl *mut u8>::add}, val: Value(<ZST>) }
+      }
+  
+      bb1: {
+          StorageDead(_5);                 // scope 3 at $DIR/sibling_ptr.rs:+4:17: +4:18
+          (*_4) = const 1_u8;              // scope 3 at $DIR/sibling_ptr.rs:+4:9: +4:22
+          StorageDead(_4);                 // scope 3 at $DIR/sibling_ptr.rs:+4:22: +4:23
+          _2 = const ();                   // scope 2 at $DIR/sibling_ptr.rs:+2:5: +5:6
+          StorageDead(_3);                 // scope 2 at $DIR/sibling_ptr.rs:+5:5: +5:6
+          StorageDead(_2);                 // scope 1 at $DIR/sibling_ptr.rs:+5:5: +5:6
+          StorageLive(_6);                 // scope 1 at $DIR/sibling_ptr.rs:+6:9: +6:11
+          _6 = (_1.1: u8);                 // scope 1 at $DIR/sibling_ptr.rs:+6:14: +6:17
+          _0 = const ();                   // scope 0 at $DIR/sibling_ptr.rs:+0:11: +7:2
+          StorageDead(_6);                 // scope 1 at $DIR/sibling_ptr.rs:+7:1: +7:2
+          StorageDead(_1);                 // scope 0 at $DIR/sibling_ptr.rs:+7:1: +7:2
+          return;                          // scope 0 at $DIR/sibling_ptr.rs:+7:2: +7:2
+      }
+  }
+  
diff --git a/src/test/mir-opt/dataflow-const-prop/sibling_ptr.rs b/src/test/mir-opt/dataflow-const-prop/sibling_ptr.rs
new file mode 100644
index 000000000000..87ef00d18295
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/sibling_ptr.rs
@@ -0,0 +1,11 @@
+// unit-test: DataflowConstProp
+
+// EMIT_MIR sibling_ptr.main.DataflowConstProp.diff
+fn main() {
+    let mut x: (u8, u8) = (0, 0);
+    unsafe {
+        let p = std::ptr::addr_of_mut!(x.0);
+        *p.add(1) = 1;
+    }
+    let x1 = x.1;  // should not be propagated
+}
diff --git a/src/test/mir-opt/dataflow-const-prop/struct.main.DataflowConstProp.diff b/src/test/mir-opt/dataflow-const-prop/struct.main.DataflowConstProp.diff
new file mode 100644
index 000000000000..cfb2706c167c
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/struct.main.DataflowConstProp.diff
@@ -0,0 +1,52 @@
+- // MIR for `main` before DataflowConstProp
++ // MIR for `main` after DataflowConstProp
+  
+  fn main() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/struct.rs:+0:11: +0:11
+      let mut _1: S;                       // in scope 0 at $DIR/struct.rs:+1:9: +1:14
+      let mut _3: i32;                     // in scope 0 at $DIR/struct.rs:+2:13: +2:16
+      let mut _5: i32;                     // in scope 0 at $DIR/struct.rs:+4:13: +4:14
+      let mut _6: i32;                     // in scope 0 at $DIR/struct.rs:+4:17: +4:20
+      scope 1 {
+          debug s => _1;                   // in scope 1 at $DIR/struct.rs:+1:9: +1:14
+          let _2: i32;                     // in scope 1 at $DIR/struct.rs:+2:9: +2:10
+          scope 2 {
+              debug a => _2;               // in scope 2 at $DIR/struct.rs:+2:9: +2:10
+              let _4: i32;                 // in scope 2 at $DIR/struct.rs:+4:9: +4:10
+              scope 3 {
+                  debug b => _4;           // in scope 3 at $DIR/struct.rs:+4:9: +4:10
+              }
+          }
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/struct.rs:+1:9: +1:14
+          Deinit(_1);                      // scope 0 at $DIR/struct.rs:+1:17: +1:21
+          (_1.0: i32) = const 1_i32;       // scope 0 at $DIR/struct.rs:+1:17: +1:21
+          StorageLive(_2);                 // scope 1 at $DIR/struct.rs:+2:9: +2:10
+          StorageLive(_3);                 // scope 1 at $DIR/struct.rs:+2:13: +2:16
+-         _3 = (_1.0: i32);                // scope 1 at $DIR/struct.rs:+2:13: +2:16
+-         _2 = Add(move _3, const 2_i32);  // scope 1 at $DIR/struct.rs:+2:13: +2:20
++         _3 = const 1_i32;                // scope 1 at $DIR/struct.rs:+2:13: +2:16
++         _2 = const 3_i32;                // scope 1 at $DIR/struct.rs:+2:13: +2:20
+          StorageDead(_3);                 // scope 1 at $DIR/struct.rs:+2:19: +2:20
+          (_1.0: i32) = const 3_i32;       // scope 2 at $DIR/struct.rs:+3:5: +3:12
+          StorageLive(_4);                 // scope 2 at $DIR/struct.rs:+4:9: +4:10
+          StorageLive(_5);                 // scope 2 at $DIR/struct.rs:+4:13: +4:14
+-         _5 = _2;                         // scope 2 at $DIR/struct.rs:+4:13: +4:14
++         _5 = const 3_i32;                // scope 2 at $DIR/struct.rs:+4:13: +4:14
+          StorageLive(_6);                 // scope 2 at $DIR/struct.rs:+4:17: +4:20
+-         _6 = (_1.0: i32);                // scope 2 at $DIR/struct.rs:+4:17: +4:20
+-         _4 = Add(move _5, move _6);      // scope 2 at $DIR/struct.rs:+4:13: +4:20
++         _6 = const 3_i32;                // scope 2 at $DIR/struct.rs:+4:17: +4:20
++         _4 = const 6_i32;                // scope 2 at $DIR/struct.rs:+4:13: +4:20
+          StorageDead(_6);                 // scope 2 at $DIR/struct.rs:+4:19: +4:20
+          StorageDead(_5);                 // scope 2 at $DIR/struct.rs:+4:19: +4:20
+          _0 = const ();                   // scope 0 at $DIR/struct.rs:+0:11: +5:2
+          StorageDead(_4);                 // scope 2 at $DIR/struct.rs:+5:1: +5:2
+          StorageDead(_2);                 // scope 1 at $DIR/struct.rs:+5:1: +5:2
+          StorageDead(_1);                 // scope 0 at $DIR/struct.rs:+5:1: +5:2
+          return;                          // scope 0 at $DIR/struct.rs:+5:2: +5:2
+      }
+  }
+  
diff --git a/src/test/mir-opt/dataflow-const-prop/struct.rs b/src/test/mir-opt/dataflow-const-prop/struct.rs
new file mode 100644
index 000000000000..841b279e03ee
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/struct.rs
@@ -0,0 +1,11 @@
+// unit-test: DataflowConstProp
+
+struct S(i32);
+
+// EMIT_MIR struct.main.DataflowConstProp.diff
+fn main() {
+    let mut s = S(1);
+    let a = s.0 + 2;
+    s.0 = 3;
+    let b = a + s.0;
+}
diff --git a/src/test/mir-opt/dataflow-const-prop/terminator.main.DataflowConstProp.diff b/src/test/mir-opt/dataflow-const-prop/terminator.main.DataflowConstProp.diff
new file mode 100644
index 000000000000..8018400e798a
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/terminator.main.DataflowConstProp.diff
@@ -0,0 +1,40 @@
+- // MIR for `main` before DataflowConstProp
++ // MIR for `main` after DataflowConstProp
+  
+  fn main() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/terminator.rs:+0:11: +0:11
+      let _1: i32;                         // in scope 0 at $DIR/terminator.rs:+1:9: +1:10
+      let _2: ();                          // in scope 0 at $DIR/terminator.rs:+3:5: +3:15
+      let mut _3: i32;                     // in scope 0 at $DIR/terminator.rs:+3:9: +3:14
+      let mut _4: i32;                     // in scope 0 at $DIR/terminator.rs:+3:9: +3:10
+      scope 1 {
+          debug a => _1;                   // in scope 1 at $DIR/terminator.rs:+1:9: +1:10
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/terminator.rs:+1:9: +1:10
+          _1 = const 1_i32;                // scope 0 at $DIR/terminator.rs:+1:13: +1:14
+          StorageLive(_2);                 // scope 1 at $DIR/terminator.rs:+3:5: +3:15
+          StorageLive(_3);                 // scope 1 at $DIR/terminator.rs:+3:9: +3:14
+          StorageLive(_4);                 // scope 1 at $DIR/terminator.rs:+3:9: +3:10
+-         _4 = _1;                         // scope 1 at $DIR/terminator.rs:+3:9: +3:10
+-         _3 = Add(move _4, const 1_i32);  // scope 1 at $DIR/terminator.rs:+3:9: +3:14
++         _4 = const 1_i32;                // scope 1 at $DIR/terminator.rs:+3:9: +3:10
++         _3 = const 2_i32;                // scope 1 at $DIR/terminator.rs:+3:9: +3:14
+          StorageDead(_4);                 // scope 1 at $DIR/terminator.rs:+3:13: +3:14
+-         _2 = foo(move _3) -> bb1;        // scope 1 at $DIR/terminator.rs:+3:5: +3:15
++         _2 = foo(const 2_i32) -> bb1;    // scope 1 at $DIR/terminator.rs:+3:5: +3:15
+                                           // mir::Constant
+                                           // + span: $DIR/terminator.rs:9:5: 9:8
+                                           // + literal: Const { ty: fn(i32) {foo}, val: Value(<ZST>) }
+      }
+  
+      bb1: {
+          StorageDead(_3);                 // scope 1 at $DIR/terminator.rs:+3:14: +3:15
+          StorageDead(_2);                 // scope 1 at $DIR/terminator.rs:+3:15: +3:16
+          _0 = const ();                   // scope 0 at $DIR/terminator.rs:+0:11: +4:2
+          StorageDead(_1);                 // scope 0 at $DIR/terminator.rs:+4:1: +4:2
+          return;                          // scope 0 at $DIR/terminator.rs:+4:2: +4:2
+      }
+  }
+  
diff --git a/src/test/mir-opt/dataflow-const-prop/terminator.rs b/src/test/mir-opt/dataflow-const-prop/terminator.rs
new file mode 100644
index 000000000000..d151f666a2dc
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/terminator.rs
@@ -0,0 +1,10 @@
+// unit-test: DataflowConstProp
+
+fn foo(n: i32) {}
+
+// EMIT_MIR terminator.main.DataflowConstProp.diff
+fn main() {
+    let a = 1;
+    // Checks that we propagate into terminators.
+    foo(a + 1);
+}
diff --git a/src/test/mir-opt/dataflow-const-prop/tuple.main.DataflowConstProp.diff b/src/test/mir-opt/dataflow-const-prop/tuple.main.DataflowConstProp.diff
new file mode 100644
index 000000000000..e028def00a11
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/tuple.main.DataflowConstProp.diff
@@ -0,0 +1,75 @@
+- // MIR for `main` before DataflowConstProp
++ // MIR for `main` after DataflowConstProp
+  
+  fn main() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/tuple.rs:+0:11: +0:11
+      let mut _1: (i32, i32);              // in scope 0 at $DIR/tuple.rs:+1:9: +1:14
+      let mut _3: i32;                     // in scope 0 at $DIR/tuple.rs:+2:13: +2:22
+      let mut _4: i32;                     // in scope 0 at $DIR/tuple.rs:+2:13: +2:16
+      let mut _5: i32;                     // in scope 0 at $DIR/tuple.rs:+2:19: +2:22
+      let mut _7: i32;                     // in scope 0 at $DIR/tuple.rs:+4:13: +4:22
+      let mut _8: i32;                     // in scope 0 at $DIR/tuple.rs:+4:13: +4:16
+      let mut _9: i32;                     // in scope 0 at $DIR/tuple.rs:+4:19: +4:22
+      let mut _10: i32;                    // in scope 0 at $DIR/tuple.rs:+4:25: +4:26
+      scope 1 {
+          debug a => _1;                   // in scope 1 at $DIR/tuple.rs:+1:9: +1:14
+          let _2: i32;                     // in scope 1 at $DIR/tuple.rs:+2:9: +2:10
+          scope 2 {
+              debug b => _2;               // in scope 2 at $DIR/tuple.rs:+2:9: +2:10
+              let _6: i32;                 // in scope 2 at $DIR/tuple.rs:+4:9: +4:10
+              scope 3 {
+                  debug c => _6;           // in scope 3 at $DIR/tuple.rs:+4:9: +4:10
+              }
+          }
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/tuple.rs:+1:9: +1:14
+          Deinit(_1);                      // scope 0 at $DIR/tuple.rs:+1:17: +1:23
+          (_1.0: i32) = const 1_i32;       // scope 0 at $DIR/tuple.rs:+1:17: +1:23
+          (_1.1: i32) = const 2_i32;       // scope 0 at $DIR/tuple.rs:+1:17: +1:23
+          StorageLive(_2);                 // scope 1 at $DIR/tuple.rs:+2:9: +2:10
+          StorageLive(_3);                 // scope 1 at $DIR/tuple.rs:+2:13: +2:22
+          StorageLive(_4);                 // scope 1 at $DIR/tuple.rs:+2:13: +2:16
+-         _4 = (_1.0: i32);                // scope 1 at $DIR/tuple.rs:+2:13: +2:16
++         _4 = const 1_i32;                // scope 1 at $DIR/tuple.rs:+2:13: +2:16
+          StorageLive(_5);                 // scope 1 at $DIR/tuple.rs:+2:19: +2:22
+-         _5 = (_1.1: i32);                // scope 1 at $DIR/tuple.rs:+2:19: +2:22
+-         _3 = Add(move _4, move _5);      // scope 1 at $DIR/tuple.rs:+2:13: +2:22
++         _5 = const 2_i32;                // scope 1 at $DIR/tuple.rs:+2:19: +2:22
++         _3 = const 3_i32;                // scope 1 at $DIR/tuple.rs:+2:13: +2:22
+          StorageDead(_5);                 // scope 1 at $DIR/tuple.rs:+2:21: +2:22
+          StorageDead(_4);                 // scope 1 at $DIR/tuple.rs:+2:21: +2:22
+-         _2 = Add(move _3, const 3_i32);  // scope 1 at $DIR/tuple.rs:+2:13: +2:26
++         _2 = const 6_i32;                // scope 1 at $DIR/tuple.rs:+2:13: +2:26
+          StorageDead(_3);                 // scope 1 at $DIR/tuple.rs:+2:25: +2:26
+          Deinit(_1);                      // scope 2 at $DIR/tuple.rs:+3:5: +3:15
+          (_1.0: i32) = const 2_i32;       // scope 2 at $DIR/tuple.rs:+3:5: +3:15
+          (_1.1: i32) = const 3_i32;       // scope 2 at $DIR/tuple.rs:+3:5: +3:15
+          StorageLive(_6);                 // scope 2 at $DIR/tuple.rs:+4:9: +4:10
+          StorageLive(_7);                 // scope 2 at $DIR/tuple.rs:+4:13: +4:22
+          StorageLive(_8);                 // scope 2 at $DIR/tuple.rs:+4:13: +4:16
+-         _8 = (_1.0: i32);                // scope 2 at $DIR/tuple.rs:+4:13: +4:16
++         _8 = const 2_i32;                // scope 2 at $DIR/tuple.rs:+4:13: +4:16
+          StorageLive(_9);                 // scope 2 at $DIR/tuple.rs:+4:19: +4:22
+-         _9 = (_1.1: i32);                // scope 2 at $DIR/tuple.rs:+4:19: +4:22
+-         _7 = Add(move _8, move _9);      // scope 2 at $DIR/tuple.rs:+4:13: +4:22
++         _9 = const 3_i32;                // scope 2 at $DIR/tuple.rs:+4:19: +4:22
++         _7 = const 5_i32;                // scope 2 at $DIR/tuple.rs:+4:13: +4:22
+          StorageDead(_9);                 // scope 2 at $DIR/tuple.rs:+4:21: +4:22
+          StorageDead(_8);                 // scope 2 at $DIR/tuple.rs:+4:21: +4:22
+          StorageLive(_10);                // scope 2 at $DIR/tuple.rs:+4:25: +4:26
+-         _10 = _2;                        // scope 2 at $DIR/tuple.rs:+4:25: +4:26
+-         _6 = Add(move _7, move _10);     // scope 2 at $DIR/tuple.rs:+4:13: +4:26
++         _10 = const 6_i32;               // scope 2 at $DIR/tuple.rs:+4:25: +4:26
++         _6 = const 11_i32;               // scope 2 at $DIR/tuple.rs:+4:13: +4:26
+          StorageDead(_10);                // scope 2 at $DIR/tuple.rs:+4:25: +4:26
+          StorageDead(_7);                 // scope 2 at $DIR/tuple.rs:+4:25: +4:26
+          _0 = const ();                   // scope 0 at $DIR/tuple.rs:+0:11: +5:2
+          StorageDead(_6);                 // scope 2 at $DIR/tuple.rs:+5:1: +5:2
+          StorageDead(_2);                 // scope 1 at $DIR/tuple.rs:+5:1: +5:2
+          StorageDead(_1);                 // scope 0 at $DIR/tuple.rs:+5:1: +5:2
+          return;                          // scope 0 at $DIR/tuple.rs:+5:2: +5:2
+      }
+  }
+  
diff --git a/src/test/mir-opt/dataflow-const-prop/tuple.rs b/src/test/mir-opt/dataflow-const-prop/tuple.rs
new file mode 100644
index 000000000000..92c70eab0ff6
--- /dev/null
+++ b/src/test/mir-opt/dataflow-const-prop/tuple.rs
@@ -0,0 +1,9 @@
+// unit-test: DataflowConstProp
+
+// EMIT_MIR tuple.main.DataflowConstProp.diff
+fn main() {
+    let mut a = (1, 2);
+    let b = a.0 + a.1 + 3;
+    a = (2, 3);
+    let c = a.0 + a.1 + b;
+}
diff --git a/src/test/mir-opt/exponential_or.match_tuple.SimplifyCfg-initial.after.mir b/src/test/mir-opt/exponential_or.match_tuple.SimplifyCfg-initial.after.mir
index 96716a39a2bf..08481777ed49 100644
--- a/src/test/mir-opt/exponential_or.match_tuple.SimplifyCfg-initial.after.mir
+++ b/src/test/mir-opt/exponential_or.match_tuple.SimplifyCfg-initial.after.mir
@@ -1,83 +1,83 @@
 // MIR for `match_tuple` after SimplifyCfg-initial
 
 fn match_tuple(_1: (u32, bool, Option<i32>, u32)) -> u32 {
-    debug x => _1;                       // in scope 0 at $DIR/exponential-or.rs:+0:16: +0:17
-    let mut _0: u32;                     // return place in scope 0 at $DIR/exponential-or.rs:+0:53: +0:56
-    let mut _2: isize;                   // in scope 0 at $DIR/exponential-or.rs:+2:37: +2:48
-    let mut _3: bool;                    // in scope 0 at $DIR/exponential-or.rs:+2:70: +2:77
-    let mut _4: bool;                    // in scope 0 at $DIR/exponential-or.rs:+2:70: +2:77
-    let mut _5: bool;                    // in scope 0 at $DIR/exponential-or.rs:+2:62: +2:67
-    let mut _6: bool;                    // in scope 0 at $DIR/exponential-or.rs:+2:62: +2:67
-    let _7: u32;                         // in scope 0 at $DIR/exponential-or.rs:+2:10: +2:11
-    let _8: u32;                         // in scope 0 at $DIR/exponential-or.rs:+2:57: +2:58
-    let mut _9: u32;                     // in scope 0 at $DIR/exponential-or.rs:+2:83: +2:84
-    let mut _10: u32;                    // in scope 0 at $DIR/exponential-or.rs:+2:87: +2:88
+    debug x => _1;                       // in scope 0 at $DIR/exponential_or.rs:+0:16: +0:17
+    let mut _0: u32;                     // return place in scope 0 at $DIR/exponential_or.rs:+0:53: +0:56
+    let mut _2: isize;                   // in scope 0 at $DIR/exponential_or.rs:+2:37: +2:48
+    let mut _3: bool;                    // in scope 0 at $DIR/exponential_or.rs:+2:70: +2:77
+    let mut _4: bool;                    // in scope 0 at $DIR/exponential_or.rs:+2:70: +2:77
+    let mut _5: bool;                    // in scope 0 at $DIR/exponential_or.rs:+2:62: +2:67
+    let mut _6: bool;                    // in scope 0 at $DIR/exponential_or.rs:+2:62: +2:67
+    let _7: u32;                         // in scope 0 at $DIR/exponential_or.rs:+2:10: +2:11
+    let _8: u32;                         // in scope 0 at $DIR/exponential_or.rs:+2:57: +2:58
+    let mut _9: u32;                     // in scope 0 at $DIR/exponential_or.rs:+2:83: +2:84
+    let mut _10: u32;                    // in scope 0 at $DIR/exponential_or.rs:+2:87: +2:88
     scope 1 {
-        debug y => _7;                   // in scope 1 at $DIR/exponential-or.rs:+2:10: +2:11
-        debug z => _8;                   // in scope 1 at $DIR/exponential-or.rs:+2:57: +2:58
+        debug y => _7;                   // in scope 1 at $DIR/exponential_or.rs:+2:10: +2:11
+        debug z => _8;                   // in scope 1 at $DIR/exponential_or.rs:+2:57: +2:58
     }
 
     bb0: {
-        FakeRead(ForMatchedPlace(None), _1); // scope 0 at $DIR/exponential-or.rs:+1:11: +1:12
-        switchInt((_1.0: u32)) -> [1_u32: bb2, 4_u32: bb2, otherwise: bb1]; // scope 0 at $DIR/exponential-or.rs:+2:15: +2:20
+        FakeRead(ForMatchedPlace(None), _1); // scope 0 at $DIR/exponential_or.rs:+1:11: +1:12
+        switchInt((_1.0: u32)) -> [1_u32: bb2, 4_u32: bb2, otherwise: bb1]; // scope 0 at $DIR/exponential_or.rs:+2:15: +2:20
     }
 
     bb1: {
-        _0 = const 0_u32;                // scope 0 at $DIR/exponential-or.rs:+3:14: +3:15
-        goto -> bb10;                    // scope 0 at $DIR/exponential-or.rs:+3:14: +3:15
+        _0 = const 0_u32;                // scope 0 at $DIR/exponential_or.rs:+3:14: +3:15
+        goto -> bb10;                    // scope 0 at $DIR/exponential_or.rs:+3:14: +3:15
     }
 
     bb2: {
-        _2 = discriminant((_1.2: std::option::Option<i32>)); // scope 0 at $DIR/exponential-or.rs:+2:37: +2:55
-        switchInt(move _2) -> [0_isize: bb4, 1_isize: bb3, otherwise: bb1]; // scope 0 at $DIR/exponential-or.rs:+2:37: +2:55
+        _2 = discriminant((_1.2: std::option::Option<i32>)); // scope 0 at $DIR/exponential_or.rs:+2:37: +2:55
+        switchInt(move _2) -> [0_isize: bb4, 1_isize: bb3, otherwise: bb1]; // scope 0 at $DIR/exponential_or.rs:+2:37: +2:55
     }
 
     bb3: {
-        switchInt((((_1.2: std::option::Option<i32>) as Some).0: i32)) -> [1_i32: bb4, 8_i32: bb4, otherwise: bb1]; // scope 0 at $DIR/exponential-or.rs:+2:37: +2:55
+        switchInt((((_1.2: std::option::Option<i32>) as Some).0: i32)) -> [1_i32: bb4, 8_i32: bb4, otherwise: bb1]; // scope 0 at $DIR/exponential_or.rs:+2:37: +2:55
     }
 
     bb4: {
-        _5 = Le(const 6_u32, (_1.3: u32)); // scope 0 at $DIR/exponential-or.rs:+2:62: +2:67
-        switchInt(move _5) -> [false: bb6, otherwise: bb5]; // scope 0 at $DIR/exponential-or.rs:+2:62: +2:67
+        _5 = Le(const 6_u32, (_1.3: u32)); // scope 0 at $DIR/exponential_or.rs:+2:62: +2:67
+        switchInt(move _5) -> [false: bb6, otherwise: bb5]; // scope 0 at $DIR/exponential_or.rs:+2:62: +2:67
     }
 
     bb5: {
-        _6 = Le((_1.3: u32), const 9_u32); // scope 0 at $DIR/exponential-or.rs:+2:62: +2:67
-        switchInt(move _6) -> [false: bb6, otherwise: bb8]; // scope 0 at $DIR/exponential-or.rs:+2:62: +2:67
+        _6 = Le((_1.3: u32), const 9_u32); // scope 0 at $DIR/exponential_or.rs:+2:62: +2:67
+        switchInt(move _6) -> [false: bb6, otherwise: bb8]; // scope 0 at $DIR/exponential_or.rs:+2:62: +2:67
     }
 
     bb6: {
-        _3 = Le(const 13_u32, (_1.3: u32)); // scope 0 at $DIR/exponential-or.rs:+2:70: +2:77
-        switchInt(move _3) -> [false: bb1, otherwise: bb7]; // scope 0 at $DIR/exponential-or.rs:+2:70: +2:77
+        _3 = Le(const 13_u32, (_1.3: u32)); // scope 0 at $DIR/exponential_or.rs:+2:70: +2:77
+        switchInt(move _3) -> [false: bb1, otherwise: bb7]; // scope 0 at $DIR/exponential_or.rs:+2:70: +2:77
     }
 
     bb7: {
-        _4 = Le((_1.3: u32), const 16_u32); // scope 0 at $DIR/exponential-or.rs:+2:70: +2:77
-        switchInt(move _4) -> [false: bb1, otherwise: bb8]; // scope 0 at $DIR/exponential-or.rs:+2:70: +2:77
+        _4 = Le((_1.3: u32), const 16_u32); // scope 0 at $DIR/exponential_or.rs:+2:70: +2:77
+        switchInt(move _4) -> [false: bb1, otherwise: bb8]; // scope 0 at $DIR/exponential_or.rs:+2:70: +2:77
     }
 
     bb8: {
-        falseEdge -> [real: bb9, imaginary: bb1]; // scope 0 at $DIR/exponential-or.rs:+2:9: +2:79
+        falseEdge -> [real: bb9, imaginary: bb1]; // scope 0 at $DIR/exponential_or.rs:+2:9: +2:79
     }
 
     bb9: {
-        StorageLive(_7);                 // scope 0 at $DIR/exponential-or.rs:+2:10: +2:11
-        _7 = (_1.0: u32);                // scope 0 at $DIR/exponential-or.rs:+2:10: +2:11
-        StorageLive(_8);                 // scope 0 at $DIR/exponential-or.rs:+2:57: +2:58
-        _8 = (_1.3: u32);                // scope 0 at $DIR/exponential-or.rs:+2:57: +2:58
-        StorageLive(_9);                 // scope 1 at $DIR/exponential-or.rs:+2:83: +2:84
-        _9 = _7;                         // scope 1 at $DIR/exponential-or.rs:+2:83: +2:84
-        StorageLive(_10);                // scope 1 at $DIR/exponential-or.rs:+2:87: +2:88
-        _10 = _8;                        // scope 1 at $DIR/exponential-or.rs:+2:87: +2:88
-        _0 = BitXor(move _9, move _10);  // scope 1 at $DIR/exponential-or.rs:+2:83: +2:88
-        StorageDead(_10);                // scope 1 at $DIR/exponential-or.rs:+2:87: +2:88
-        StorageDead(_9);                 // scope 1 at $DIR/exponential-or.rs:+2:87: +2:88
-        StorageDead(_8);                 // scope 0 at $DIR/exponential-or.rs:+2:87: +2:88
-        StorageDead(_7);                 // scope 0 at $DIR/exponential-or.rs:+2:87: +2:88
-        goto -> bb10;                    // scope 0 at $DIR/exponential-or.rs:+2:87: +2:88
+        StorageLive(_7);                 // scope 0 at $DIR/exponential_or.rs:+2:10: +2:11
+        _7 = (_1.0: u32);                // scope 0 at $DIR/exponential_or.rs:+2:10: +2:11
+        StorageLive(_8);                 // scope 0 at $DIR/exponential_or.rs:+2:57: +2:58
+        _8 = (_1.3: u32);                // scope 0 at $DIR/exponential_or.rs:+2:57: +2:58
+        StorageLive(_9);                 // scope 1 at $DIR/exponential_or.rs:+2:83: +2:84
+        _9 = _7;                         // scope 1 at $DIR/exponential_or.rs:+2:83: +2:84
+        StorageLive(_10);                // scope 1 at $DIR/exponential_or.rs:+2:87: +2:88
+        _10 = _8;                        // scope 1 at $DIR/exponential_or.rs:+2:87: +2:88
+        _0 = BitXor(move _9, move _10);  // scope 1 at $DIR/exponential_or.rs:+2:83: +2:88
+        StorageDead(_10);                // scope 1 at $DIR/exponential_or.rs:+2:87: +2:88
+        StorageDead(_9);                 // scope 1 at $DIR/exponential_or.rs:+2:87: +2:88
+        StorageDead(_8);                 // scope 0 at $DIR/exponential_or.rs:+2:87: +2:88
+        StorageDead(_7);                 // scope 0 at $DIR/exponential_or.rs:+2:87: +2:88
+        goto -> bb10;                    // scope 0 at $DIR/exponential_or.rs:+2:87: +2:88
     }
 
     bb10: {
-        return;                          // scope 0 at $DIR/exponential-or.rs:+5:2: +5:2
+        return;                          // scope 0 at $DIR/exponential_or.rs:+5:2: +5:2
     }
 }
diff --git a/src/test/mir-opt/exponential-or.rs b/src/test/mir-opt/exponential_or.rs
similarity index 100%
rename from src/test/mir-opt/exponential-or.rs
rename to src/test/mir-opt/exponential_or.rs
diff --git a/src/test/mir-opt/fn-ptr-shim.rs b/src/test/mir-opt/fn_ptr_shim.rs
similarity index 100%
rename from src/test/mir-opt/fn-ptr-shim.rs
rename to src/test/mir-opt/fn_ptr_shim.rs
diff --git a/src/test/mir-opt/generator_drop_cleanup.main-{closure#0}.generator_drop.0.mir b/src/test/mir-opt/generator_drop_cleanup.main-{closure#0}.generator_drop.0.mir
index c718138b6b37..c3b08bf06489 100644
--- a/src/test/mir-opt/generator_drop_cleanup.main-{closure#0}.generator_drop.0.mir
+++ b/src/test/mir-opt/generator_drop_cleanup.main-{closure#0}.generator_drop.0.mir
@@ -14,71 +14,71 @@
     },
 } */
 
-fn main::{closure#0}(_1: *mut [generator@$DIR/generator-drop-cleanup.rs:10:15: 10:17]) -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/generator-drop-cleanup.rs:+0:15: +3:6
-    let mut _2: ();                      // in scope 0 at $DIR/generator-drop-cleanup.rs:+0:15: +3:6
-    let _3: std::string::String;         // in scope 0 at $DIR/generator-drop-cleanup.rs:+1:13: +1:15
-    let _4: ();                          // in scope 0 at $DIR/generator-drop-cleanup.rs:+2:9: +2:14
-    let mut _5: ();                      // in scope 0 at $DIR/generator-drop-cleanup.rs:+2:9: +2:14
-    let mut _6: ();                      // in scope 0 at $DIR/generator-drop-cleanup.rs:+0:18: +0:18
-    let mut _7: ();                      // in scope 0 at $DIR/generator-drop-cleanup.rs:+0:15: +3:6
-    let mut _8: u32;                     // in scope 0 at $DIR/generator-drop-cleanup.rs:+0:15: +3:6
+fn main::{closure#0}(_1: *mut [generator@$DIR/generator_drop_cleanup.rs:10:15: 10:17]) -> () {
+    let mut _0: ();                      // return place in scope 0 at $DIR/generator_drop_cleanup.rs:+0:15: +3:6
+    let mut _2: ();                      // in scope 0 at $DIR/generator_drop_cleanup.rs:+0:15: +3:6
+    let _3: std::string::String;         // in scope 0 at $DIR/generator_drop_cleanup.rs:+1:13: +1:15
+    let _4: ();                          // in scope 0 at $DIR/generator_drop_cleanup.rs:+2:9: +2:14
+    let mut _5: ();                      // in scope 0 at $DIR/generator_drop_cleanup.rs:+2:9: +2:14
+    let mut _6: ();                      // in scope 0 at $DIR/generator_drop_cleanup.rs:+0:18: +0:18
+    let mut _7: ();                      // in scope 0 at $DIR/generator_drop_cleanup.rs:+0:15: +3:6
+    let mut _8: u32;                     // in scope 0 at $DIR/generator_drop_cleanup.rs:+0:15: +3:6
     scope 1 {
-        debug _s => (((*_1) as variant#3).0: std::string::String); // in scope 1 at $DIR/generator-drop-cleanup.rs:+1:13: +1:15
+        debug _s => (((*_1) as variant#3).0: std::string::String); // in scope 1 at $DIR/generator_drop_cleanup.rs:+1:13: +1:15
     }
 
     bb0: {
-        _8 = discriminant((*_1));        // scope 0 at $DIR/generator-drop-cleanup.rs:+0:15: +3:6
-        switchInt(move _8) -> [0_u32: bb7, 3_u32: bb10, otherwise: bb11]; // scope 0 at $DIR/generator-drop-cleanup.rs:+0:15: +3:6
+        _8 = discriminant((*_1));        // scope 0 at $DIR/generator_drop_cleanup.rs:+0:15: +3:6
+        switchInt(move _8) -> [0_u32: bb7, 3_u32: bb10, otherwise: bb11]; // scope 0 at $DIR/generator_drop_cleanup.rs:+0:15: +3:6
     }
 
     bb1: {
-        StorageDead(_5);                 // scope 1 at $DIR/generator-drop-cleanup.rs:+2:13: +2:14
-        StorageDead(_4);                 // scope 1 at $DIR/generator-drop-cleanup.rs:+2:14: +2:15
-        drop((((*_1) as variant#3).0: std::string::String)) -> [return: bb2, unwind: bb5]; // scope 0 at $DIR/generator-drop-cleanup.rs:+3:5: +3:6
+        StorageDead(_5);                 // scope 1 at $DIR/generator_drop_cleanup.rs:+2:13: +2:14
+        StorageDead(_4);                 // scope 1 at $DIR/generator_drop_cleanup.rs:+2:14: +2:15
+        drop((((*_1) as variant#3).0: std::string::String)) -> [return: bb2, unwind: bb5]; // scope 0 at $DIR/generator_drop_cleanup.rs:+3:5: +3:6
     }
 
     bb2: {
-        nop;                             // scope 0 at $DIR/generator-drop-cleanup.rs:+3:5: +3:6
-        goto -> bb8;                     // scope 0 at $DIR/generator-drop-cleanup.rs:+3:5: +3:6
+        nop;                             // scope 0 at $DIR/generator_drop_cleanup.rs:+3:5: +3:6
+        goto -> bb8;                     // scope 0 at $DIR/generator_drop_cleanup.rs:+3:5: +3:6
     }
 
     bb3: {
-        return;                          // scope 0 at $DIR/generator-drop-cleanup.rs:+0:15: +3:6
+        return;                          // scope 0 at $DIR/generator_drop_cleanup.rs:+0:15: +3:6
     }
 
     bb4 (cleanup): {
-        resume;                          // scope 0 at $DIR/generator-drop-cleanup.rs:+0:15: +3:6
+        resume;                          // scope 0 at $DIR/generator_drop_cleanup.rs:+0:15: +3:6
     }
 
     bb5 (cleanup): {
-        nop;                             // scope 0 at $DIR/generator-drop-cleanup.rs:+3:5: +3:6
-        goto -> bb4;                     // scope 0 at $DIR/generator-drop-cleanup.rs:+3:5: +3:6
+        nop;                             // scope 0 at $DIR/generator_drop_cleanup.rs:+3:5: +3:6
+        goto -> bb4;                     // scope 0 at $DIR/generator_drop_cleanup.rs:+3:5: +3:6
     }
 
     bb6: {
-        return;                          // scope 0 at $DIR/generator-drop-cleanup.rs:+0:15: +3:6
+        return;                          // scope 0 at $DIR/generator_drop_cleanup.rs:+0:15: +3:6
     }
 
     bb7: {
-        goto -> bb9;                     // scope 0 at $DIR/generator-drop-cleanup.rs:+0:15: +3:6
+        goto -> bb9;                     // scope 0 at $DIR/generator_drop_cleanup.rs:+0:15: +3:6
     }
 
     bb8: {
-        goto -> bb3;                     // scope 0 at $DIR/generator-drop-cleanup.rs:+3:5: +3:6
+        goto -> bb3;                     // scope 0 at $DIR/generator_drop_cleanup.rs:+3:5: +3:6
     }
 
     bb9: {
-        goto -> bb6;                     // scope 0 at $DIR/generator-drop-cleanup.rs:+0:15: +3:6
+        goto -> bb6;                     // scope 0 at $DIR/generator_drop_cleanup.rs:+0:15: +3:6
     }
 
     bb10: {
-        StorageLive(_4);                 // scope 0 at $DIR/generator-drop-cleanup.rs:+0:15: +3:6
-        StorageLive(_5);                 // scope 0 at $DIR/generator-drop-cleanup.rs:+0:15: +3:6
-        goto -> bb1;                     // scope 0 at $DIR/generator-drop-cleanup.rs:+0:15: +3:6
+        StorageLive(_4);                 // scope 0 at $DIR/generator_drop_cleanup.rs:+0:15: +3:6
+        StorageLive(_5);                 // scope 0 at $DIR/generator_drop_cleanup.rs:+0:15: +3:6
+        goto -> bb1;                     // scope 0 at $DIR/generator_drop_cleanup.rs:+0:15: +3:6
     }
 
     bb11: {
-        return;                          // scope 0 at $DIR/generator-drop-cleanup.rs:+0:15: +3:6
+        return;                          // scope 0 at $DIR/generator_drop_cleanup.rs:+0:15: +3:6
     }
 }
diff --git a/src/test/mir-opt/generator-drop-cleanup.rs b/src/test/mir-opt/generator_drop_cleanup.rs
similarity index 100%
rename from src/test/mir-opt/generator-drop-cleanup.rs
rename to src/test/mir-opt/generator_drop_cleanup.rs
diff --git a/src/test/mir-opt/generator_storage_dead_unwind.main-{closure#0}.StateTransform.before.mir b/src/test/mir-opt/generator_storage_dead_unwind.main-{closure#0}.StateTransform.before.mir
index 3184343f207b..cfbe0aaf252d 100644
--- a/src/test/mir-opt/generator_storage_dead_unwind.main-{closure#0}.StateTransform.before.mir
+++ b/src/test/mir-opt/generator_storage_dead_unwind.main-{closure#0}.StateTransform.before.mir
@@ -1,124 +1,124 @@
 // MIR for `main::{closure#0}` before StateTransform
 
-fn main::{closure#0}(_1: [generator@$DIR/generator-storage-dead-unwind.rs:22:16: 22:18], _2: ()) -> ()
+fn main::{closure#0}(_1: [generator@$DIR/generator_storage_dead_unwind.rs:22:16: 22:18], _2: ()) -> ()
 yields ()
  {
-    let mut _0: ();                      // return place in scope 0 at $DIR/generator-storage-dead-unwind.rs:+0:19: +0:19
-    let _3: Foo;                         // in scope 0 at $DIR/generator-storage-dead-unwind.rs:+1:13: +1:14
-    let _5: ();                          // in scope 0 at $DIR/generator-storage-dead-unwind.rs:+3:9: +3:14
-    let mut _6: ();                      // in scope 0 at $DIR/generator-storage-dead-unwind.rs:+3:9: +3:14
-    let _7: ();                          // in scope 0 at $DIR/generator-storage-dead-unwind.rs:+4:9: +4:16
-    let mut _8: Foo;                     // in scope 0 at $DIR/generator-storage-dead-unwind.rs:+4:14: +4:15
-    let _9: ();                          // in scope 0 at $DIR/generator-storage-dead-unwind.rs:+5:9: +5:16
-    let mut _10: Bar;                    // in scope 0 at $DIR/generator-storage-dead-unwind.rs:+5:14: +5:15
+    let mut _0: ();                      // return place in scope 0 at $DIR/generator_storage_dead_unwind.rs:+0:19: +0:19
+    let _3: Foo;                         // in scope 0 at $DIR/generator_storage_dead_unwind.rs:+1:13: +1:14
+    let _5: ();                          // in scope 0 at $DIR/generator_storage_dead_unwind.rs:+3:9: +3:14
+    let mut _6: ();                      // in scope 0 at $DIR/generator_storage_dead_unwind.rs:+3:9: +3:14
+    let _7: ();                          // in scope 0 at $DIR/generator_storage_dead_unwind.rs:+4:9: +4:16
+    let mut _8: Foo;                     // in scope 0 at $DIR/generator_storage_dead_unwind.rs:+4:14: +4:15
+    let _9: ();                          // in scope 0 at $DIR/generator_storage_dead_unwind.rs:+5:9: +5:16
+    let mut _10: Bar;                    // in scope 0 at $DIR/generator_storage_dead_unwind.rs:+5:14: +5:15
     scope 1 {
-        debug a => _3;                   // in scope 1 at $DIR/generator-storage-dead-unwind.rs:+1:13: +1:14
-        let _4: Bar;                     // in scope 1 at $DIR/generator-storage-dead-unwind.rs:+2:13: +2:14
+        debug a => _3;                   // in scope 1 at $DIR/generator_storage_dead_unwind.rs:+1:13: +1:14
+        let _4: Bar;                     // in scope 1 at $DIR/generator_storage_dead_unwind.rs:+2:13: +2:14
         scope 2 {
-            debug b => _4;               // in scope 2 at $DIR/generator-storage-dead-unwind.rs:+2:13: +2:14
+            debug b => _4;               // in scope 2 at $DIR/generator_storage_dead_unwind.rs:+2:13: +2:14
         }
     }
 
     bb0: {
-        StorageLive(_3);                 // scope 0 at $DIR/generator-storage-dead-unwind.rs:+1:13: +1:14
-        _3 = Foo(const 5_i32);           // scope 0 at $DIR/generator-storage-dead-unwind.rs:+1:17: +1:23
-        StorageLive(_4);                 // scope 1 at $DIR/generator-storage-dead-unwind.rs:+2:13: +2:14
-        _4 = Bar(const 6_i32);           // scope 1 at $DIR/generator-storage-dead-unwind.rs:+2:17: +2:23
-        StorageLive(_5);                 // scope 2 at $DIR/generator-storage-dead-unwind.rs:+3:9: +3:14
-        StorageLive(_6);                 // scope 2 at $DIR/generator-storage-dead-unwind.rs:+3:9: +3:14
-        _6 = ();                         // scope 2 at $DIR/generator-storage-dead-unwind.rs:+3:9: +3:14
-        _5 = yield(move _6) -> [resume: bb1, drop: bb6]; // scope 2 at $DIR/generator-storage-dead-unwind.rs:+3:9: +3:14
+        StorageLive(_3);                 // scope 0 at $DIR/generator_storage_dead_unwind.rs:+1:13: +1:14
+        _3 = Foo(const 5_i32);           // scope 0 at $DIR/generator_storage_dead_unwind.rs:+1:17: +1:23
+        StorageLive(_4);                 // scope 1 at $DIR/generator_storage_dead_unwind.rs:+2:13: +2:14
+        _4 = Bar(const 6_i32);           // scope 1 at $DIR/generator_storage_dead_unwind.rs:+2:17: +2:23
+        StorageLive(_5);                 // scope 2 at $DIR/generator_storage_dead_unwind.rs:+3:9: +3:14
+        StorageLive(_6);                 // scope 2 at $DIR/generator_storage_dead_unwind.rs:+3:9: +3:14
+        _6 = ();                         // scope 2 at $DIR/generator_storage_dead_unwind.rs:+3:9: +3:14
+        _5 = yield(move _6) -> [resume: bb1, drop: bb6]; // scope 2 at $DIR/generator_storage_dead_unwind.rs:+3:9: +3:14
     }
 
     bb1: {
-        StorageDead(_6);                 // scope 2 at $DIR/generator-storage-dead-unwind.rs:+3:13: +3:14
-        StorageDead(_5);                 // scope 2 at $DIR/generator-storage-dead-unwind.rs:+3:14: +3:15
-        StorageLive(_7);                 // scope 2 at $DIR/generator-storage-dead-unwind.rs:+4:9: +4:16
-        StorageLive(_8);                 // scope 2 at $DIR/generator-storage-dead-unwind.rs:+4:14: +4:15
-        _8 = move _3;                    // scope 2 at $DIR/generator-storage-dead-unwind.rs:+4:14: +4:15
-        _7 = take::<Foo>(move _8) -> [return: bb2, unwind: bb10]; // scope 2 at $DIR/generator-storage-dead-unwind.rs:+4:9: +4:16
+        StorageDead(_6);                 // scope 2 at $DIR/generator_storage_dead_unwind.rs:+3:13: +3:14
+        StorageDead(_5);                 // scope 2 at $DIR/generator_storage_dead_unwind.rs:+3:14: +3:15
+        StorageLive(_7);                 // scope 2 at $DIR/generator_storage_dead_unwind.rs:+4:9: +4:16
+        StorageLive(_8);                 // scope 2 at $DIR/generator_storage_dead_unwind.rs:+4:14: +4:15
+        _8 = move _3;                    // scope 2 at $DIR/generator_storage_dead_unwind.rs:+4:14: +4:15
+        _7 = take::<Foo>(move _8) -> [return: bb2, unwind: bb10]; // scope 2 at $DIR/generator_storage_dead_unwind.rs:+4:9: +4:16
                                          // mir::Constant
-                                         // + span: $DIR/generator-storage-dead-unwind.rs:26:9: 26:13
+                                         // + span: $DIR/generator_storage_dead_unwind.rs:26:9: 26:13
                                          // + literal: Const { ty: fn(Foo) {take::<Foo>}, val: Value(<ZST>) }
     }
 
     bb2: {
-        StorageDead(_8);                 // scope 2 at $DIR/generator-storage-dead-unwind.rs:+4:15: +4:16
-        StorageDead(_7);                 // scope 2 at $DIR/generator-storage-dead-unwind.rs:+4:16: +4:17
-        StorageLive(_9);                 // scope 2 at $DIR/generator-storage-dead-unwind.rs:+5:9: +5:16
-        StorageLive(_10);                // scope 2 at $DIR/generator-storage-dead-unwind.rs:+5:14: +5:15
-        _10 = move _4;                   // scope 2 at $DIR/generator-storage-dead-unwind.rs:+5:14: +5:15
-        _9 = take::<Bar>(move _10) -> [return: bb3, unwind: bb9]; // scope 2 at $DIR/generator-storage-dead-unwind.rs:+5:9: +5:16
+        StorageDead(_8);                 // scope 2 at $DIR/generator_storage_dead_unwind.rs:+4:15: +4:16
+        StorageDead(_7);                 // scope 2 at $DIR/generator_storage_dead_unwind.rs:+4:16: +4:17
+        StorageLive(_9);                 // scope 2 at $DIR/generator_storage_dead_unwind.rs:+5:9: +5:16
+        StorageLive(_10);                // scope 2 at $DIR/generator_storage_dead_unwind.rs:+5:14: +5:15
+        _10 = move _4;                   // scope 2 at $DIR/generator_storage_dead_unwind.rs:+5:14: +5:15
+        _9 = take::<Bar>(move _10) -> [return: bb3, unwind: bb9]; // scope 2 at $DIR/generator_storage_dead_unwind.rs:+5:9: +5:16
                                          // mir::Constant
-                                         // + span: $DIR/generator-storage-dead-unwind.rs:27:9: 27:13
+                                         // + span: $DIR/generator_storage_dead_unwind.rs:27:9: 27:13
                                          // + literal: Const { ty: fn(Bar) {take::<Bar>}, val: Value(<ZST>) }
     }
 
     bb3: {
-        StorageDead(_10);                // scope 2 at $DIR/generator-storage-dead-unwind.rs:+5:15: +5:16
-        StorageDead(_9);                 // scope 2 at $DIR/generator-storage-dead-unwind.rs:+5:16: +5:17
-        _0 = const ();                   // scope 0 at $DIR/generator-storage-dead-unwind.rs:+0:19: +6:6
-        StorageDead(_4);                 // scope 1 at $DIR/generator-storage-dead-unwind.rs:+6:5: +6:6
-        goto -> bb4;                     // scope 0 at $DIR/generator-storage-dead-unwind.rs:+6:5: +6:6
+        StorageDead(_10);                // scope 2 at $DIR/generator_storage_dead_unwind.rs:+5:15: +5:16
+        StorageDead(_9);                 // scope 2 at $DIR/generator_storage_dead_unwind.rs:+5:16: +5:17
+        _0 = const ();                   // scope 0 at $DIR/generator_storage_dead_unwind.rs:+0:19: +6:6
+        StorageDead(_4);                 // scope 1 at $DIR/generator_storage_dead_unwind.rs:+6:5: +6:6
+        goto -> bb4;                     // scope 0 at $DIR/generator_storage_dead_unwind.rs:+6:5: +6:6
     }
 
     bb4: {
-        StorageDead(_3);                 // scope 0 at $DIR/generator-storage-dead-unwind.rs:+6:5: +6:6
-        drop(_1) -> [return: bb5, unwind: bb14]; // scope 0 at $DIR/generator-storage-dead-unwind.rs:+6:5: +6:6
+        StorageDead(_3);                 // scope 0 at $DIR/generator_storage_dead_unwind.rs:+6:5: +6:6
+        drop(_1) -> [return: bb5, unwind: bb14]; // scope 0 at $DIR/generator_storage_dead_unwind.rs:+6:5: +6:6
     }
 
     bb5: {
-        return;                          // scope 0 at $DIR/generator-storage-dead-unwind.rs:+6:6: +6:6
+        return;                          // scope 0 at $DIR/generator_storage_dead_unwind.rs:+6:6: +6:6
     }
 
     bb6: {
-        StorageDead(_6);                 // scope 2 at $DIR/generator-storage-dead-unwind.rs:+3:13: +3:14
-        StorageDead(_5);                 // scope 2 at $DIR/generator-storage-dead-unwind.rs:+3:14: +3:15
-        StorageDead(_4);                 // scope 1 at $DIR/generator-storage-dead-unwind.rs:+6:5: +6:6
-        drop(_3) -> [return: bb7, unwind: bb15]; // scope 0 at $DIR/generator-storage-dead-unwind.rs:+6:5: +6:6
+        StorageDead(_6);                 // scope 2 at $DIR/generator_storage_dead_unwind.rs:+3:13: +3:14
+        StorageDead(_5);                 // scope 2 at $DIR/generator_storage_dead_unwind.rs:+3:14: +3:15
+        StorageDead(_4);                 // scope 1 at $DIR/generator_storage_dead_unwind.rs:+6:5: +6:6
+        drop(_3) -> [return: bb7, unwind: bb15]; // scope 0 at $DIR/generator_storage_dead_unwind.rs:+6:5: +6:6
     }
 
     bb7: {
-        StorageDead(_3);                 // scope 0 at $DIR/generator-storage-dead-unwind.rs:+6:5: +6:6
-        drop(_1) -> [return: bb8, unwind: bb14]; // scope 0 at $DIR/generator-storage-dead-unwind.rs:+6:5: +6:6
+        StorageDead(_3);                 // scope 0 at $DIR/generator_storage_dead_unwind.rs:+6:5: +6:6
+        drop(_1) -> [return: bb8, unwind: bb14]; // scope 0 at $DIR/generator_storage_dead_unwind.rs:+6:5: +6:6
     }
 
     bb8: {
-        generator_drop;                  // scope 0 at $DIR/generator-storage-dead-unwind.rs:+0:16: +6:6
+        generator_drop;                  // scope 0 at $DIR/generator_storage_dead_unwind.rs:+0:16: +6:6
     }
 
     bb9 (cleanup): {
-        StorageDead(_10);                // scope 2 at $DIR/generator-storage-dead-unwind.rs:+5:15: +5:16
-        StorageDead(_9);                 // scope 2 at $DIR/generator-storage-dead-unwind.rs:+5:16: +5:17
+        StorageDead(_10);                // scope 2 at $DIR/generator_storage_dead_unwind.rs:+5:15: +5:16
+        StorageDead(_9);                 // scope 2 at $DIR/generator_storage_dead_unwind.rs:+5:16: +5:17
         goto -> bb12;                    // scope 2 at no-location
     }
 
     bb10 (cleanup): {
-        goto -> bb11;                    // scope 2 at $DIR/generator-storage-dead-unwind.rs:+4:15: +4:16
+        goto -> bb11;                    // scope 2 at $DIR/generator_storage_dead_unwind.rs:+4:15: +4:16
     }
 
     bb11 (cleanup): {
-        StorageDead(_8);                 // scope 2 at $DIR/generator-storage-dead-unwind.rs:+4:15: +4:16
-        StorageDead(_7);                 // scope 2 at $DIR/generator-storage-dead-unwind.rs:+4:16: +4:17
+        StorageDead(_8);                 // scope 2 at $DIR/generator_storage_dead_unwind.rs:+4:15: +4:16
+        StorageDead(_7);                 // scope 2 at $DIR/generator_storage_dead_unwind.rs:+4:16: +4:17
         goto -> bb12;                    // scope 2 at no-location
     }
 
     bb12 (cleanup): {
-        StorageDead(_4);                 // scope 1 at $DIR/generator-storage-dead-unwind.rs:+6:5: +6:6
-        goto -> bb13;                    // scope 0 at $DIR/generator-storage-dead-unwind.rs:+6:5: +6:6
+        StorageDead(_4);                 // scope 1 at $DIR/generator_storage_dead_unwind.rs:+6:5: +6:6
+        goto -> bb13;                    // scope 0 at $DIR/generator_storage_dead_unwind.rs:+6:5: +6:6
     }
 
     bb13 (cleanup): {
-        StorageDead(_3);                 // scope 0 at $DIR/generator-storage-dead-unwind.rs:+6:5: +6:6
-        drop(_1) -> bb14;                // scope 0 at $DIR/generator-storage-dead-unwind.rs:+6:5: +6:6
+        StorageDead(_3);                 // scope 0 at $DIR/generator_storage_dead_unwind.rs:+6:5: +6:6
+        drop(_1) -> bb14;                // scope 0 at $DIR/generator_storage_dead_unwind.rs:+6:5: +6:6
     }
 
     bb14 (cleanup): {
-        resume;                          // scope 0 at $DIR/generator-storage-dead-unwind.rs:+0:16: +6:6
+        resume;                          // scope 0 at $DIR/generator_storage_dead_unwind.rs:+0:16: +6:6
     }
 
     bb15 (cleanup): {
-        StorageDead(_3);                 // scope 0 at $DIR/generator-storage-dead-unwind.rs:+6:5: +6:6
-        drop(_1) -> bb14;                // scope 0 at $DIR/generator-storage-dead-unwind.rs:+6:5: +6:6
+        StorageDead(_3);                 // scope 0 at $DIR/generator_storage_dead_unwind.rs:+6:5: +6:6
+        drop(_1) -> bb14;                // scope 0 at $DIR/generator_storage_dead_unwind.rs:+6:5: +6:6
     }
 }
diff --git a/src/test/mir-opt/generator-storage-dead-unwind.rs b/src/test/mir-opt/generator_storage_dead_unwind.rs
similarity index 100%
rename from src/test/mir-opt/generator-storage-dead-unwind.rs
rename to src/test/mir-opt/generator_storage_dead_unwind.rs
diff --git a/src/test/mir-opt/generator_tiny.main-{closure#0}.generator_resume.0.mir b/src/test/mir-opt/generator_tiny.main-{closure#0}.generator_resume.0.mir
index 07aeeaae012c..fee6da2c6352 100644
--- a/src/test/mir-opt/generator_tiny.main-{closure#0}.generator_resume.0.mir
+++ b/src/test/mir-opt/generator_tiny.main-{closure#0}.generator_resume.0.mir
@@ -14,71 +14,71 @@
     },
 } */
 
-fn main::{closure#0}(_1: Pin<&mut [generator@$DIR/generator-tiny.rs:19:16: 19:24]>, _2: u8) -> GeneratorState<(), ()> {
-    debug _x => _10;                     // in scope 0 at $DIR/generator-tiny.rs:+0:17: +0:19
-    let mut _0: std::ops::GeneratorState<(), ()>; // return place in scope 0 at $DIR/generator-tiny.rs:+0:16: +6:6
-    let _3: HasDrop;                     // in scope 0 at $DIR/generator-tiny.rs:+1:13: +1:15
-    let mut _4: !;                       // in scope 0 at $DIR/generator-tiny.rs:+2:9: +5:10
-    let mut _5: ();                      // in scope 0 at $DIR/generator-tiny.rs:+0:16: +6:6
-    let _6: u8;                          // in scope 0 at $DIR/generator-tiny.rs:+3:13: +3:18
-    let mut _7: ();                      // in scope 0 at $DIR/generator-tiny.rs:+3:13: +3:18
-    let _8: ();                          // in scope 0 at $DIR/generator-tiny.rs:+4:13: +4:21
-    let mut _9: ();                      // in scope 0 at $DIR/generator-tiny.rs:+0:25: +0:25
-    let _10: u8;                         // in scope 0 at $DIR/generator-tiny.rs:+0:17: +0:19
-    let mut _11: u32;                    // in scope 0 at $DIR/generator-tiny.rs:+0:16: +6:6
+fn main::{closure#0}(_1: Pin<&mut [generator@$DIR/generator_tiny.rs:19:16: 19:24]>, _2: u8) -> GeneratorState<(), ()> {
+    debug _x => _10;                     // in scope 0 at $DIR/generator_tiny.rs:+0:17: +0:19
+    let mut _0: std::ops::GeneratorState<(), ()>; // return place in scope 0 at $DIR/generator_tiny.rs:+0:16: +6:6
+    let _3: HasDrop;                     // in scope 0 at $DIR/generator_tiny.rs:+1:13: +1:15
+    let mut _4: !;                       // in scope 0 at $DIR/generator_tiny.rs:+2:9: +5:10
+    let mut _5: ();                      // in scope 0 at $DIR/generator_tiny.rs:+0:16: +6:6
+    let _6: u8;                          // in scope 0 at $DIR/generator_tiny.rs:+3:13: +3:18
+    let mut _7: ();                      // in scope 0 at $DIR/generator_tiny.rs:+3:13: +3:18
+    let _8: ();                          // in scope 0 at $DIR/generator_tiny.rs:+4:13: +4:21
+    let mut _9: ();                      // in scope 0 at $DIR/generator_tiny.rs:+0:25: +0:25
+    let _10: u8;                         // in scope 0 at $DIR/generator_tiny.rs:+0:17: +0:19
+    let mut _11: u32;                    // in scope 0 at $DIR/generator_tiny.rs:+0:16: +6:6
     scope 1 {
-        debug _d => (((*(_1.0: &mut [generator@$DIR/generator-tiny.rs:19:16: 19:24])) as variant#3).0: HasDrop); // in scope 1 at $DIR/generator-tiny.rs:+1:13: +1:15
+        debug _d => (((*(_1.0: &mut [generator@$DIR/generator_tiny.rs:19:16: 19:24])) as variant#3).0: HasDrop); // in scope 1 at $DIR/generator_tiny.rs:+1:13: +1:15
     }
 
     bb0: {
-        _11 = discriminant((*(_1.0: &mut [generator@$DIR/generator-tiny.rs:19:16: 19:24]))); // scope 0 at $DIR/generator-tiny.rs:+0:16: +6:6
-        switchInt(move _11) -> [0_u32: bb1, 3_u32: bb5, otherwise: bb6]; // scope 0 at $DIR/generator-tiny.rs:+0:16: +6:6
+        _11 = discriminant((*(_1.0: &mut [generator@$DIR/generator_tiny.rs:19:16: 19:24]))); // scope 0 at $DIR/generator_tiny.rs:+0:16: +6:6
+        switchInt(move _11) -> [0_u32: bb1, 3_u32: bb5, otherwise: bb6]; // scope 0 at $DIR/generator_tiny.rs:+0:16: +6:6
     }
 
     bb1: {
-        _10 = move _2;                   // scope 0 at $DIR/generator-tiny.rs:+0:16: +6:6
-        nop;                             // scope 0 at $DIR/generator-tiny.rs:+1:13: +1:15
-        (((*(_1.0: &mut [generator@$DIR/generator-tiny.rs:19:16: 19:24])) as variant#3).0: HasDrop) = HasDrop; // scope 0 at $DIR/generator-tiny.rs:+1:18: +1:25
-        StorageLive(_4);                 // scope 1 at $DIR/generator-tiny.rs:+2:9: +5:10
-        goto -> bb2;                     // scope 1 at $DIR/generator-tiny.rs:+2:9: +5:10
+        _10 = move _2;                   // scope 0 at $DIR/generator_tiny.rs:+0:16: +6:6
+        nop;                             // scope 0 at $DIR/generator_tiny.rs:+1:13: +1:15
+        (((*(_1.0: &mut [generator@$DIR/generator_tiny.rs:19:16: 19:24])) as variant#3).0: HasDrop) = HasDrop; // scope 0 at $DIR/generator_tiny.rs:+1:18: +1:25
+        StorageLive(_4);                 // scope 1 at $DIR/generator_tiny.rs:+2:9: +5:10
+        goto -> bb2;                     // scope 1 at $DIR/generator_tiny.rs:+2:9: +5:10
     }
 
     bb2: {
-        StorageLive(_6);                 // scope 1 at $DIR/generator-tiny.rs:+3:13: +3:18
-        StorageLive(_7);                 // scope 1 at $DIR/generator-tiny.rs:+3:13: +3:18
-        _7 = ();                         // scope 1 at $DIR/generator-tiny.rs:+3:13: +3:18
-        Deinit(_0);                      // scope 1 at $DIR/generator-tiny.rs:+3:13: +3:18
-        ((_0 as Yielded).0: ()) = move _7; // scope 1 at $DIR/generator-tiny.rs:+3:13: +3:18
-        discriminant(_0) = 0;            // scope 1 at $DIR/generator-tiny.rs:+3:13: +3:18
-        discriminant((*(_1.0: &mut [generator@$DIR/generator-tiny.rs:19:16: 19:24]))) = 3; // scope 1 at $DIR/generator-tiny.rs:+3:13: +3:18
-        return;                          // scope 1 at $DIR/generator-tiny.rs:+3:13: +3:18
+        StorageLive(_6);                 // scope 1 at $DIR/generator_tiny.rs:+3:13: +3:18
+        StorageLive(_7);                 // scope 1 at $DIR/generator_tiny.rs:+3:13: +3:18
+        _7 = ();                         // scope 1 at $DIR/generator_tiny.rs:+3:13: +3:18
+        Deinit(_0);                      // scope 1 at $DIR/generator_tiny.rs:+3:13: +3:18
+        ((_0 as Yielded).0: ()) = move _7; // scope 1 at $DIR/generator_tiny.rs:+3:13: +3:18
+        discriminant(_0) = 0;            // scope 1 at $DIR/generator_tiny.rs:+3:13: +3:18
+        discriminant((*(_1.0: &mut [generator@$DIR/generator_tiny.rs:19:16: 19:24]))) = 3; // scope 1 at $DIR/generator_tiny.rs:+3:13: +3:18
+        return;                          // scope 1 at $DIR/generator_tiny.rs:+3:13: +3:18
     }
 
     bb3: {
-        StorageDead(_7);                 // scope 1 at $DIR/generator-tiny.rs:+3:17: +3:18
-        StorageDead(_6);                 // scope 1 at $DIR/generator-tiny.rs:+3:18: +3:19
-        StorageLive(_8);                 // scope 1 at $DIR/generator-tiny.rs:+4:13: +4:21
-        _8 = callee() -> bb4;            // scope 1 at $DIR/generator-tiny.rs:+4:13: +4:21
+        StorageDead(_7);                 // scope 1 at $DIR/generator_tiny.rs:+3:17: +3:18
+        StorageDead(_6);                 // scope 1 at $DIR/generator_tiny.rs:+3:18: +3:19
+        StorageLive(_8);                 // scope 1 at $DIR/generator_tiny.rs:+4:13: +4:21
+        _8 = callee() -> bb4;            // scope 1 at $DIR/generator_tiny.rs:+4:13: +4:21
                                          // mir::Constant
-                                         // + span: $DIR/generator-tiny.rs:23:13: 23:19
+                                         // + span: $DIR/generator_tiny.rs:23:13: 23:19
                                          // + literal: Const { ty: fn() {callee}, val: Value(<ZST>) }
     }
 
     bb4: {
-        StorageDead(_8);                 // scope 1 at $DIR/generator-tiny.rs:+4:21: +4:22
-        _5 = const ();                   // scope 1 at $DIR/generator-tiny.rs:+2:14: +5:10
-        goto -> bb2;                     // scope 1 at $DIR/generator-tiny.rs:+2:9: +5:10
+        StorageDead(_8);                 // scope 1 at $DIR/generator_tiny.rs:+4:21: +4:22
+        _5 = const ();                   // scope 1 at $DIR/generator_tiny.rs:+2:14: +5:10
+        goto -> bb2;                     // scope 1 at $DIR/generator_tiny.rs:+2:9: +5:10
     }
 
     bb5: {
-        StorageLive(_4);                 // scope 0 at $DIR/generator-tiny.rs:+0:16: +6:6
-        StorageLive(_6);                 // scope 0 at $DIR/generator-tiny.rs:+0:16: +6:6
-        StorageLive(_7);                 // scope 0 at $DIR/generator-tiny.rs:+0:16: +6:6
-        _6 = move _2;                    // scope 0 at $DIR/generator-tiny.rs:+0:16: +6:6
-        goto -> bb3;                     // scope 0 at $DIR/generator-tiny.rs:+0:16: +6:6
+        StorageLive(_4);                 // scope 0 at $DIR/generator_tiny.rs:+0:16: +6:6
+        StorageLive(_6);                 // scope 0 at $DIR/generator_tiny.rs:+0:16: +6:6
+        StorageLive(_7);                 // scope 0 at $DIR/generator_tiny.rs:+0:16: +6:6
+        _6 = move _2;                    // scope 0 at $DIR/generator_tiny.rs:+0:16: +6:6
+        goto -> bb3;                     // scope 0 at $DIR/generator_tiny.rs:+0:16: +6:6
     }
 
     bb6: {
-        unreachable;                     // scope 0 at $DIR/generator-tiny.rs:+0:16: +6:6
+        unreachable;                     // scope 0 at $DIR/generator_tiny.rs:+0:16: +6:6
     }
 }
diff --git a/src/test/mir-opt/generator-tiny.rs b/src/test/mir-opt/generator_tiny.rs
similarity index 100%
rename from src/test/mir-opt/generator-tiny.rs
rename to src/test/mir-opt/generator_tiny.rs
diff --git a/src/test/mir-opt/graphviz.main.mir_map.0.dot b/src/test/mir-opt/graphviz.main.built.after.dot
similarity index 100%
rename from src/test/mir-opt/graphviz.main.mir_map.0.dot
rename to src/test/mir-opt/graphviz.main.built.after.dot
diff --git a/src/test/mir-opt/graphviz.rs b/src/test/mir-opt/graphviz.rs
index 074dba2c3738..6906b86c2a5f 100644
--- a/src/test/mir-opt/graphviz.rs
+++ b/src/test/mir-opt/graphviz.rs
@@ -1,5 +1,5 @@
 // Test graphviz output
 // compile-flags: -Z dump-mir-graphviz
 
-// EMIT_MIR graphviz.main.mir_map.0.dot
+// EMIT_MIR graphviz.main.built.after.dot
 fn main() {}
diff --git a/src/test/mir-opt/if_condition_int.dont_opt_bool.SimplifyComparisonIntegral.diff b/src/test/mir-opt/if_condition_int.dont_opt_bool.SimplifyComparisonIntegral.diff
index 19b5ab44156f..94180d203439 100644
--- a/src/test/mir-opt/if_condition_int.dont_opt_bool.SimplifyComparisonIntegral.diff
+++ b/src/test/mir-opt/if_condition_int.dont_opt_bool.SimplifyComparisonIntegral.diff
@@ -2,29 +2,29 @@
 + // MIR for `dont_opt_bool` after SimplifyComparisonIntegral
   
   fn dont_opt_bool(_1: bool) -> u32 {
-      debug x => _1;                       // in scope 0 at $DIR/if-condition-int.rs:+0:18: +0:19
-      let mut _0: u32;                     // return place in scope 0 at $DIR/if-condition-int.rs:+0:30: +0:33
-      let mut _2: bool;                    // in scope 0 at $DIR/if-condition-int.rs:+1:8: +1:9
+      debug x => _1;                       // in scope 0 at $DIR/if_condition_int.rs:+0:18: +0:19
+      let mut _0: u32;                     // return place in scope 0 at $DIR/if_condition_int.rs:+0:30: +0:33
+      let mut _2: bool;                    // in scope 0 at $DIR/if_condition_int.rs:+1:8: +1:9
   
       bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:9
-          _2 = _1;                         // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:9
-          switchInt(move _2) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:9
+          StorageLive(_2);                 // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:9
+          _2 = _1;                         // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:9
+          switchInt(move _2) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:9
       }
   
       bb1: {
-          _0 = const 0_u32;                // scope 0 at $DIR/if-condition-int.rs:+1:12: +1:13
-          goto -> bb3;                     // scope 0 at $DIR/if-condition-int.rs:+1:5: +1:26
+          _0 = const 0_u32;                // scope 0 at $DIR/if_condition_int.rs:+1:12: +1:13
+          goto -> bb3;                     // scope 0 at $DIR/if_condition_int.rs:+1:5: +1:26
       }
   
       bb2: {
-          _0 = const 1_u32;                // scope 0 at $DIR/if-condition-int.rs:+1:23: +1:24
-          goto -> bb3;                     // scope 0 at $DIR/if-condition-int.rs:+1:5: +1:26
+          _0 = const 1_u32;                // scope 0 at $DIR/if_condition_int.rs:+1:23: +1:24
+          goto -> bb3;                     // scope 0 at $DIR/if_condition_int.rs:+1:5: +1:26
       }
   
       bb3: {
-          StorageDead(_2);                 // scope 0 at $DIR/if-condition-int.rs:+1:25: +1:26
-          return;                          // scope 0 at $DIR/if-condition-int.rs:+2:2: +2:2
+          StorageDead(_2);                 // scope 0 at $DIR/if_condition_int.rs:+1:25: +1:26
+          return;                          // scope 0 at $DIR/if_condition_int.rs:+2:2: +2:2
       }
   }
   
diff --git a/src/test/mir-opt/if_condition_int.dont_opt_floats.SimplifyComparisonIntegral.diff b/src/test/mir-opt/if_condition_int.dont_opt_floats.SimplifyComparisonIntegral.diff
index 256af7b94be2..b22c7eac622f 100644
--- a/src/test/mir-opt/if_condition_int.dont_opt_floats.SimplifyComparisonIntegral.diff
+++ b/src/test/mir-opt/if_condition_int.dont_opt_floats.SimplifyComparisonIntegral.diff
@@ -2,33 +2,33 @@
 + // MIR for `dont_opt_floats` after SimplifyComparisonIntegral
   
   fn dont_opt_floats(_1: f32) -> i32 {
-      debug a => _1;                       // in scope 0 at $DIR/if-condition-int.rs:+0:20: +0:21
-      let mut _0: i32;                     // return place in scope 0 at $DIR/if-condition-int.rs:+0:31: +0:34
-      let mut _2: bool;                    // in scope 0 at $DIR/if-condition-int.rs:+1:8: +1:18
-      let mut _3: f32;                     // in scope 0 at $DIR/if-condition-int.rs:+1:8: +1:9
+      debug a => _1;                       // in scope 0 at $DIR/if_condition_int.rs:+0:20: +0:21
+      let mut _0: i32;                     // return place in scope 0 at $DIR/if_condition_int.rs:+0:31: +0:34
+      let mut _2: bool;                    // in scope 0 at $DIR/if_condition_int.rs:+1:8: +1:18
+      let mut _3: f32;                     // in scope 0 at $DIR/if_condition_int.rs:+1:8: +1:9
   
       bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:18
-          StorageLive(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:9
-          _3 = _1;                         // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:9
-          _2 = Eq(move _3, const -42f32);  // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:18
-          StorageDead(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:17: +1:18
-          switchInt(move _2) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:18
+          StorageLive(_2);                 // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:18
+          StorageLive(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:9
+          _3 = _1;                         // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:9
+          _2 = Eq(move _3, const -42f32);  // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:18
+          StorageDead(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:17: +1:18
+          switchInt(move _2) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:18
       }
   
       bb1: {
-          _0 = const 0_i32;                // scope 0 at $DIR/if-condition-int.rs:+1:21: +1:22
-          goto -> bb3;                     // scope 0 at $DIR/if-condition-int.rs:+1:5: +1:35
+          _0 = const 0_i32;                // scope 0 at $DIR/if_condition_int.rs:+1:21: +1:22
+          goto -> bb3;                     // scope 0 at $DIR/if_condition_int.rs:+1:5: +1:35
       }
   
       bb2: {
-          _0 = const 1_i32;                // scope 0 at $DIR/if-condition-int.rs:+1:32: +1:33
-          goto -> bb3;                     // scope 0 at $DIR/if-condition-int.rs:+1:5: +1:35
+          _0 = const 1_i32;                // scope 0 at $DIR/if_condition_int.rs:+1:32: +1:33
+          goto -> bb3;                     // scope 0 at $DIR/if_condition_int.rs:+1:5: +1:35
       }
   
       bb3: {
-          StorageDead(_2);                 // scope 0 at $DIR/if-condition-int.rs:+1:34: +1:35
-          return;                          // scope 0 at $DIR/if-condition-int.rs:+2:2: +2:2
+          StorageDead(_2);                 // scope 0 at $DIR/if_condition_int.rs:+1:34: +1:35
+          return;                          // scope 0 at $DIR/if_condition_int.rs:+2:2: +2:2
       }
   }
   
diff --git a/src/test/mir-opt/if_condition_int.dont_remove_comparison.SimplifyComparisonIntegral.diff b/src/test/mir-opt/if_condition_int.dont_remove_comparison.SimplifyComparisonIntegral.diff
index ed53c9a956ca..cc0995f99cfd 100644
--- a/src/test/mir-opt/if_condition_int.dont_remove_comparison.SimplifyComparisonIntegral.diff
+++ b/src/test/mir-opt/if_condition_int.dont_remove_comparison.SimplifyComparisonIntegral.diff
@@ -2,57 +2,57 @@
 + // MIR for `dont_remove_comparison` after SimplifyComparisonIntegral
   
   fn dont_remove_comparison(_1: i8) -> i32 {
-      debug a => _1;                       // in scope 0 at $DIR/if-condition-int.rs:+0:27: +0:28
-      let mut _0: i32;                     // return place in scope 0 at $DIR/if-condition-int.rs:+0:37: +0:40
-      let _2: bool;                        // in scope 0 at $DIR/if-condition-int.rs:+1:9: +1:10
-      let mut _3: i8;                      // in scope 0 at $DIR/if-condition-int.rs:+1:13: +1:14
-      let mut _4: i32;                     // in scope 0 at $DIR/if-condition-int.rs:+3:23: +3:31
-      let mut _5: bool;                    // in scope 0 at $DIR/if-condition-int.rs:+3:23: +3:24
-      let mut _6: i32;                     // in scope 0 at $DIR/if-condition-int.rs:+4:23: +4:31
-      let mut _7: bool;                    // in scope 0 at $DIR/if-condition-int.rs:+4:23: +4:24
+      debug a => _1;                       // in scope 0 at $DIR/if_condition_int.rs:+0:27: +0:28
+      let mut _0: i32;                     // return place in scope 0 at $DIR/if_condition_int.rs:+0:37: +0:40
+      let _2: bool;                        // in scope 0 at $DIR/if_condition_int.rs:+1:9: +1:10
+      let mut _3: i8;                      // in scope 0 at $DIR/if_condition_int.rs:+1:13: +1:14
+      let mut _4: i32;                     // in scope 0 at $DIR/if_condition_int.rs:+3:23: +3:31
+      let mut _5: bool;                    // in scope 0 at $DIR/if_condition_int.rs:+3:23: +3:24
+      let mut _6: i32;                     // in scope 0 at $DIR/if_condition_int.rs:+4:23: +4:31
+      let mut _7: bool;                    // in scope 0 at $DIR/if_condition_int.rs:+4:23: +4:24
       scope 1 {
-          debug b => _2;                   // in scope 1 at $DIR/if-condition-int.rs:+1:9: +1:10
+          debug b => _2;                   // in scope 1 at $DIR/if_condition_int.rs:+1:9: +1:10
       }
   
       bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/if-condition-int.rs:+1:9: +1:10
-          StorageLive(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:13: +1:14
-          _3 = _1;                         // scope 0 at $DIR/if-condition-int.rs:+1:13: +1:14
--         _2 = Eq(move _3, const 17_i8);   // scope 0 at $DIR/if-condition-int.rs:+1:13: +1:20
--         StorageDead(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:19: +1:20
--         switchInt(_2) -> [false: bb2, otherwise: bb1]; // scope 1 at $DIR/if-condition-int.rs:+2:5: +2:12
-+         _2 = Eq(_3, const 17_i8);        // scope 0 at $DIR/if-condition-int.rs:+1:13: +1:20
-+         nop;                             // scope 0 at $DIR/if-condition-int.rs:+1:19: +1:20
-+         switchInt(move _3) -> [17_i8: bb1, otherwise: bb2]; // scope 1 at $DIR/if-condition-int.rs:+2:5: +2:12
+          StorageLive(_2);                 // scope 0 at $DIR/if_condition_int.rs:+1:9: +1:10
+          StorageLive(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:13: +1:14
+          _3 = _1;                         // scope 0 at $DIR/if_condition_int.rs:+1:13: +1:14
+-         _2 = Eq(move _3, const 17_i8);   // scope 0 at $DIR/if_condition_int.rs:+1:13: +1:20
+-         StorageDead(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:19: +1:20
+-         switchInt(_2) -> [false: bb2, otherwise: bb1]; // scope 1 at $DIR/if_condition_int.rs:+2:5: +2:12
++         _2 = Eq(_3, const 17_i8);        // scope 0 at $DIR/if_condition_int.rs:+1:13: +1:20
++         nop;                             // scope 0 at $DIR/if_condition_int.rs:+1:19: +1:20
++         switchInt(move _3) -> [17_i8: bb1, otherwise: bb2]; // scope 1 at $DIR/if_condition_int.rs:+2:5: +2:12
       }
   
       bb1: {
-+         StorageDead(_3);                 // scope 1 at $DIR/if-condition-int.rs:+2:5: +2:12
-          StorageLive(_6);                 // scope 1 at $DIR/if-condition-int.rs:+4:23: +4:31
-          StorageLive(_7);                 // scope 1 at $DIR/if-condition-int.rs:+4:23: +4:24
-          _7 = _2;                         // scope 1 at $DIR/if-condition-int.rs:+4:23: +4:24
-          _6 = move _7 as i32 (IntToInt);  // scope 1 at $DIR/if-condition-int.rs:+4:23: +4:31
-          StorageDead(_7);                 // scope 1 at $DIR/if-condition-int.rs:+4:30: +4:31
-          _0 = Add(const 100_i32, move _6); // scope 1 at $DIR/if-condition-int.rs:+4:17: +4:31
-          StorageDead(_6);                 // scope 1 at $DIR/if-condition-int.rs:+4:30: +4:31
-          goto -> bb3;                     // scope 1 at $DIR/if-condition-int.rs:+4:30: +4:31
++         StorageDead(_3);                 // scope 1 at $DIR/if_condition_int.rs:+2:5: +2:12
+          StorageLive(_6);                 // scope 1 at $DIR/if_condition_int.rs:+4:23: +4:31
+          StorageLive(_7);                 // scope 1 at $DIR/if_condition_int.rs:+4:23: +4:24
+          _7 = _2;                         // scope 1 at $DIR/if_condition_int.rs:+4:23: +4:24
+          _6 = move _7 as i32 (IntToInt);  // scope 1 at $DIR/if_condition_int.rs:+4:23: +4:31
+          StorageDead(_7);                 // scope 1 at $DIR/if_condition_int.rs:+4:30: +4:31
+          _0 = Add(const 100_i32, move _6); // scope 1 at $DIR/if_condition_int.rs:+4:17: +4:31
+          StorageDead(_6);                 // scope 1 at $DIR/if_condition_int.rs:+4:30: +4:31
+          goto -> bb3;                     // scope 1 at $DIR/if_condition_int.rs:+4:30: +4:31
       }
   
       bb2: {
-+         StorageDead(_3);                 // scope 1 at $DIR/if-condition-int.rs:+2:5: +2:12
-          StorageLive(_4);                 // scope 1 at $DIR/if-condition-int.rs:+3:23: +3:31
-          StorageLive(_5);                 // scope 1 at $DIR/if-condition-int.rs:+3:23: +3:24
-          _5 = _2;                         // scope 1 at $DIR/if-condition-int.rs:+3:23: +3:24
-          _4 = move _5 as i32 (IntToInt);  // scope 1 at $DIR/if-condition-int.rs:+3:23: +3:31
-          StorageDead(_5);                 // scope 1 at $DIR/if-condition-int.rs:+3:30: +3:31
-          _0 = Add(const 10_i32, move _4); // scope 1 at $DIR/if-condition-int.rs:+3:18: +3:31
-          StorageDead(_4);                 // scope 1 at $DIR/if-condition-int.rs:+3:30: +3:31
-          goto -> bb3;                     // scope 1 at $DIR/if-condition-int.rs:+3:30: +3:31
++         StorageDead(_3);                 // scope 1 at $DIR/if_condition_int.rs:+2:5: +2:12
+          StorageLive(_4);                 // scope 1 at $DIR/if_condition_int.rs:+3:23: +3:31
+          StorageLive(_5);                 // scope 1 at $DIR/if_condition_int.rs:+3:23: +3:24
+          _5 = _2;                         // scope 1 at $DIR/if_condition_int.rs:+3:23: +3:24
+          _4 = move _5 as i32 (IntToInt);  // scope 1 at $DIR/if_condition_int.rs:+3:23: +3:31
+          StorageDead(_5);                 // scope 1 at $DIR/if_condition_int.rs:+3:30: +3:31
+          _0 = Add(const 10_i32, move _4); // scope 1 at $DIR/if_condition_int.rs:+3:18: +3:31
+          StorageDead(_4);                 // scope 1 at $DIR/if_condition_int.rs:+3:30: +3:31
+          goto -> bb3;                     // scope 1 at $DIR/if_condition_int.rs:+3:30: +3:31
       }
   
       bb3: {
-          StorageDead(_2);                 // scope 0 at $DIR/if-condition-int.rs:+6:1: +6:2
-          return;                          // scope 0 at $DIR/if-condition-int.rs:+6:2: +6:2
+          StorageDead(_2);                 // scope 0 at $DIR/if_condition_int.rs:+6:1: +6:2
+          return;                          // scope 0 at $DIR/if_condition_int.rs:+6:2: +6:2
       }
   }
   
diff --git a/src/test/mir-opt/if_condition_int.opt_char.SimplifyComparisonIntegral.diff b/src/test/mir-opt/if_condition_int.opt_char.SimplifyComparisonIntegral.diff
index 9b64c379fee7..801ea0402034 100644
--- a/src/test/mir-opt/if_condition_int.opt_char.SimplifyComparisonIntegral.diff
+++ b/src/test/mir-opt/if_condition_int.opt_char.SimplifyComparisonIntegral.diff
@@ -2,38 +2,38 @@
 + // MIR for `opt_char` after SimplifyComparisonIntegral
   
   fn opt_char(_1: char) -> u32 {
-      debug x => _1;                       // in scope 0 at $DIR/if-condition-int.rs:+0:13: +0:14
-      let mut _0: u32;                     // return place in scope 0 at $DIR/if-condition-int.rs:+0:25: +0:28
-      let mut _2: bool;                    // in scope 0 at $DIR/if-condition-int.rs:+1:8: +1:16
-      let mut _3: char;                    // in scope 0 at $DIR/if-condition-int.rs:+1:8: +1:9
+      debug x => _1;                       // in scope 0 at $DIR/if_condition_int.rs:+0:13: +0:14
+      let mut _0: u32;                     // return place in scope 0 at $DIR/if_condition_int.rs:+0:25: +0:28
+      let mut _2: bool;                    // in scope 0 at $DIR/if_condition_int.rs:+1:8: +1:16
+      let mut _3: char;                    // in scope 0 at $DIR/if_condition_int.rs:+1:8: +1:9
   
       bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:16
-          StorageLive(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:9
-          _3 = _1;                         // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:9
--         _2 = Eq(move _3, const 'x');     // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:16
--         StorageDead(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:15: +1:16
--         switchInt(move _2) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:16
-+         nop;                             // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:16
-+         nop;                             // scope 0 at $DIR/if-condition-int.rs:+1:15: +1:16
-+         switchInt(move _3) -> ['x': bb1, otherwise: bb2]; // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:16
+          StorageLive(_2);                 // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:16
+          StorageLive(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:9
+          _3 = _1;                         // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:9
+-         _2 = Eq(move _3, const 'x');     // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:16
+-         StorageDead(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:15: +1:16
+-         switchInt(move _2) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:16
++         nop;                             // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:16
++         nop;                             // scope 0 at $DIR/if_condition_int.rs:+1:15: +1:16
++         switchInt(move _3) -> ['x': bb1, otherwise: bb2]; // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:16
       }
   
       bb1: {
-+         StorageDead(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:16
-          _0 = const 0_u32;                // scope 0 at $DIR/if-condition-int.rs:+1:19: +1:20
-          goto -> bb3;                     // scope 0 at $DIR/if-condition-int.rs:+1:5: +1:33
++         StorageDead(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:16
+          _0 = const 0_u32;                // scope 0 at $DIR/if_condition_int.rs:+1:19: +1:20
+          goto -> bb3;                     // scope 0 at $DIR/if_condition_int.rs:+1:5: +1:33
       }
   
       bb2: {
-+         StorageDead(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:16
-          _0 = const 1_u32;                // scope 0 at $DIR/if-condition-int.rs:+1:30: +1:31
-          goto -> bb3;                     // scope 0 at $DIR/if-condition-int.rs:+1:5: +1:33
++         StorageDead(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:16
+          _0 = const 1_u32;                // scope 0 at $DIR/if_condition_int.rs:+1:30: +1:31
+          goto -> bb3;                     // scope 0 at $DIR/if_condition_int.rs:+1:5: +1:33
       }
   
       bb3: {
-          StorageDead(_2);                 // scope 0 at $DIR/if-condition-int.rs:+1:32: +1:33
-          return;                          // scope 0 at $DIR/if-condition-int.rs:+2:2: +2:2
+          StorageDead(_2);                 // scope 0 at $DIR/if_condition_int.rs:+1:32: +1:33
+          return;                          // scope 0 at $DIR/if_condition_int.rs:+2:2: +2:2
       }
   }
   
diff --git a/src/test/mir-opt/if_condition_int.opt_i8.SimplifyComparisonIntegral.diff b/src/test/mir-opt/if_condition_int.opt_i8.SimplifyComparisonIntegral.diff
index 8042d63bb34d..4297f4d64664 100644
--- a/src/test/mir-opt/if_condition_int.opt_i8.SimplifyComparisonIntegral.diff
+++ b/src/test/mir-opt/if_condition_int.opt_i8.SimplifyComparisonIntegral.diff
@@ -2,38 +2,38 @@
 + // MIR for `opt_i8` after SimplifyComparisonIntegral
   
   fn opt_i8(_1: i8) -> u32 {
-      debug x => _1;                       // in scope 0 at $DIR/if-condition-int.rs:+0:11: +0:12
-      let mut _0: u32;                     // return place in scope 0 at $DIR/if-condition-int.rs:+0:21: +0:24
-      let mut _2: bool;                    // in scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
-      let mut _3: i8;                      // in scope 0 at $DIR/if-condition-int.rs:+1:8: +1:9
+      debug x => _1;                       // in scope 0 at $DIR/if_condition_int.rs:+0:11: +0:12
+      let mut _0: u32;                     // return place in scope 0 at $DIR/if_condition_int.rs:+0:21: +0:24
+      let mut _2: bool;                    // in scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
+      let mut _3: i8;                      // in scope 0 at $DIR/if_condition_int.rs:+1:8: +1:9
   
       bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
-          StorageLive(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:9
-          _3 = _1;                         // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:9
--         _2 = Eq(move _3, const 42_i8);   // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
--         StorageDead(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:14: +1:15
--         switchInt(move _2) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
-+         nop;                             // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
-+         nop;                             // scope 0 at $DIR/if-condition-int.rs:+1:14: +1:15
-+         switchInt(move _3) -> [42_i8: bb1, otherwise: bb2]; // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
+          StorageLive(_2);                 // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
+          StorageLive(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:9
+          _3 = _1;                         // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:9
+-         _2 = Eq(move _3, const 42_i8);   // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
+-         StorageDead(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:14: +1:15
+-         switchInt(move _2) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
++         nop;                             // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
++         nop;                             // scope 0 at $DIR/if_condition_int.rs:+1:14: +1:15
++         switchInt(move _3) -> [42_i8: bb1, otherwise: bb2]; // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
       }
   
       bb1: {
-+         StorageDead(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
-          _0 = const 0_u32;                // scope 0 at $DIR/if-condition-int.rs:+1:18: +1:19
-          goto -> bb3;                     // scope 0 at $DIR/if-condition-int.rs:+1:5: +1:32
++         StorageDead(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
+          _0 = const 0_u32;                // scope 0 at $DIR/if_condition_int.rs:+1:18: +1:19
+          goto -> bb3;                     // scope 0 at $DIR/if_condition_int.rs:+1:5: +1:32
       }
   
       bb2: {
-+         StorageDead(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
-          _0 = const 1_u32;                // scope 0 at $DIR/if-condition-int.rs:+1:29: +1:30
-          goto -> bb3;                     // scope 0 at $DIR/if-condition-int.rs:+1:5: +1:32
++         StorageDead(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
+          _0 = const 1_u32;                // scope 0 at $DIR/if_condition_int.rs:+1:29: +1:30
+          goto -> bb3;                     // scope 0 at $DIR/if_condition_int.rs:+1:5: +1:32
       }
   
       bb3: {
-          StorageDead(_2);                 // scope 0 at $DIR/if-condition-int.rs:+1:31: +1:32
-          return;                          // scope 0 at $DIR/if-condition-int.rs:+2:2: +2:2
+          StorageDead(_2);                 // scope 0 at $DIR/if_condition_int.rs:+1:31: +1:32
+          return;                          // scope 0 at $DIR/if_condition_int.rs:+2:2: +2:2
       }
   }
   
diff --git a/src/test/mir-opt/if_condition_int.opt_multiple_ifs.SimplifyComparisonIntegral.diff b/src/test/mir-opt/if_condition_int.opt_multiple_ifs.SimplifyComparisonIntegral.diff
index a408de1ef3e9..8fb794abbd41 100644
--- a/src/test/mir-opt/if_condition_int.opt_multiple_ifs.SimplifyComparisonIntegral.diff
+++ b/src/test/mir-opt/if_condition_int.opt_multiple_ifs.SimplifyComparisonIntegral.diff
@@ -2,64 +2,64 @@
 + // MIR for `opt_multiple_ifs` after SimplifyComparisonIntegral
   
   fn opt_multiple_ifs(_1: u32) -> u32 {
-      debug x => _1;                       // in scope 0 at $DIR/if-condition-int.rs:+0:21: +0:22
-      let mut _0: u32;                     // return place in scope 0 at $DIR/if-condition-int.rs:+0:32: +0:35
-      let mut _2: bool;                    // in scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
-      let mut _3: u32;                     // in scope 0 at $DIR/if-condition-int.rs:+1:8: +1:9
-      let mut _4: bool;                    // in scope 0 at $DIR/if-condition-int.rs:+3:15: +3:22
-      let mut _5: u32;                     // in scope 0 at $DIR/if-condition-int.rs:+3:15: +3:16
+      debug x => _1;                       // in scope 0 at $DIR/if_condition_int.rs:+0:21: +0:22
+      let mut _0: u32;                     // return place in scope 0 at $DIR/if_condition_int.rs:+0:32: +0:35
+      let mut _2: bool;                    // in scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
+      let mut _3: u32;                     // in scope 0 at $DIR/if_condition_int.rs:+1:8: +1:9
+      let mut _4: bool;                    // in scope 0 at $DIR/if_condition_int.rs:+3:15: +3:22
+      let mut _5: u32;                     // in scope 0 at $DIR/if_condition_int.rs:+3:15: +3:16
   
       bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
-          StorageLive(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:9
-          _3 = _1;                         // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:9
--         _2 = Eq(move _3, const 42_u32);  // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
--         StorageDead(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:14: +1:15
--         switchInt(move _2) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
-+         nop;                             // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
-+         nop;                             // scope 0 at $DIR/if-condition-int.rs:+1:14: +1:15
-+         switchInt(move _3) -> [42_u32: bb1, otherwise: bb2]; // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
+          StorageLive(_2);                 // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
+          StorageLive(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:9
+          _3 = _1;                         // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:9
+-         _2 = Eq(move _3, const 42_u32);  // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
+-         StorageDead(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:14: +1:15
+-         switchInt(move _2) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
++         nop;                             // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
++         nop;                             // scope 0 at $DIR/if_condition_int.rs:+1:14: +1:15
++         switchInt(move _3) -> [42_u32: bb1, otherwise: bb2]; // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
       }
   
       bb1: {
-+         StorageDead(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
-          _0 = const 0_u32;                // scope 0 at $DIR/if-condition-int.rs:+2:9: +2:10
-          goto -> bb6;                     // scope 0 at $DIR/if-condition-int.rs:+1:5: +7:6
++         StorageDead(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
+          _0 = const 0_u32;                // scope 0 at $DIR/if_condition_int.rs:+2:9: +2:10
+          goto -> bb6;                     // scope 0 at $DIR/if_condition_int.rs:+1:5: +7:6
       }
   
       bb2: {
-+         StorageDead(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
-          StorageLive(_4);                 // scope 0 at $DIR/if-condition-int.rs:+3:15: +3:22
-          StorageLive(_5);                 // scope 0 at $DIR/if-condition-int.rs:+3:15: +3:16
-          _5 = _1;                         // scope 0 at $DIR/if-condition-int.rs:+3:15: +3:16
--         _4 = Ne(move _5, const 21_u32);  // scope 0 at $DIR/if-condition-int.rs:+3:15: +3:22
--         StorageDead(_5);                 // scope 0 at $DIR/if-condition-int.rs:+3:21: +3:22
--         switchInt(move _4) -> [false: bb4, otherwise: bb3]; // scope 0 at $DIR/if-condition-int.rs:+3:15: +3:22
-+         nop;                             // scope 0 at $DIR/if-condition-int.rs:+3:15: +3:22
-+         nop;                             // scope 0 at $DIR/if-condition-int.rs:+3:21: +3:22
-+         switchInt(move _5) -> [21_u32: bb4, otherwise: bb3]; // scope 0 at $DIR/if-condition-int.rs:+3:15: +3:22
++         StorageDead(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
+          StorageLive(_4);                 // scope 0 at $DIR/if_condition_int.rs:+3:15: +3:22
+          StorageLive(_5);                 // scope 0 at $DIR/if_condition_int.rs:+3:15: +3:16
+          _5 = _1;                         // scope 0 at $DIR/if_condition_int.rs:+3:15: +3:16
+-         _4 = Ne(move _5, const 21_u32);  // scope 0 at $DIR/if_condition_int.rs:+3:15: +3:22
+-         StorageDead(_5);                 // scope 0 at $DIR/if_condition_int.rs:+3:21: +3:22
+-         switchInt(move _4) -> [false: bb4, otherwise: bb3]; // scope 0 at $DIR/if_condition_int.rs:+3:15: +3:22
++         nop;                             // scope 0 at $DIR/if_condition_int.rs:+3:15: +3:22
++         nop;                             // scope 0 at $DIR/if_condition_int.rs:+3:21: +3:22
++         switchInt(move _5) -> [21_u32: bb4, otherwise: bb3]; // scope 0 at $DIR/if_condition_int.rs:+3:15: +3:22
       }
   
       bb3: {
-+         StorageDead(_5);                 // scope 0 at $DIR/if-condition-int.rs:+3:15: +3:22
-          _0 = const 1_u32;                // scope 0 at $DIR/if-condition-int.rs:+4:9: +4:10
-          goto -> bb5;                     // scope 0 at $DIR/if-condition-int.rs:+3:12: +7:6
++         StorageDead(_5);                 // scope 0 at $DIR/if_condition_int.rs:+3:15: +3:22
+          _0 = const 1_u32;                // scope 0 at $DIR/if_condition_int.rs:+4:9: +4:10
+          goto -> bb5;                     // scope 0 at $DIR/if_condition_int.rs:+3:12: +7:6
       }
   
       bb4: {
-+         StorageDead(_5);                 // scope 0 at $DIR/if-condition-int.rs:+3:15: +3:22
-          _0 = const 2_u32;                // scope 0 at $DIR/if-condition-int.rs:+6:9: +6:10
-          goto -> bb5;                     // scope 0 at $DIR/if-condition-int.rs:+3:12: +7:6
++         StorageDead(_5);                 // scope 0 at $DIR/if_condition_int.rs:+3:15: +3:22
+          _0 = const 2_u32;                // scope 0 at $DIR/if_condition_int.rs:+6:9: +6:10
+          goto -> bb5;                     // scope 0 at $DIR/if_condition_int.rs:+3:12: +7:6
       }
   
       bb5: {
-          StorageDead(_4);                 // scope 0 at $DIR/if-condition-int.rs:+7:5: +7:6
-          goto -> bb6;                     // scope 0 at $DIR/if-condition-int.rs:+1:5: +7:6
+          StorageDead(_4);                 // scope 0 at $DIR/if_condition_int.rs:+7:5: +7:6
+          goto -> bb6;                     // scope 0 at $DIR/if_condition_int.rs:+1:5: +7:6
       }
   
       bb6: {
-          StorageDead(_2);                 // scope 0 at $DIR/if-condition-int.rs:+7:5: +7:6
-          return;                          // scope 0 at $DIR/if-condition-int.rs:+8:2: +8:2
+          StorageDead(_2);                 // scope 0 at $DIR/if_condition_int.rs:+7:5: +7:6
+          return;                          // scope 0 at $DIR/if_condition_int.rs:+8:2: +8:2
       }
   }
   
diff --git a/src/test/mir-opt/if_condition_int.opt_negative.SimplifyComparisonIntegral.diff b/src/test/mir-opt/if_condition_int.opt_negative.SimplifyComparisonIntegral.diff
index 6802f89d9278..992253ea780d 100644
--- a/src/test/mir-opt/if_condition_int.opt_negative.SimplifyComparisonIntegral.diff
+++ b/src/test/mir-opt/if_condition_int.opt_negative.SimplifyComparisonIntegral.diff
@@ -2,38 +2,38 @@
 + // MIR for `opt_negative` after SimplifyComparisonIntegral
   
   fn opt_negative(_1: i32) -> u32 {
-      debug x => _1;                       // in scope 0 at $DIR/if-condition-int.rs:+0:17: +0:18
-      let mut _0: u32;                     // return place in scope 0 at $DIR/if-condition-int.rs:+0:28: +0:31
-      let mut _2: bool;                    // in scope 0 at $DIR/if-condition-int.rs:+1:8: +1:16
-      let mut _3: i32;                     // in scope 0 at $DIR/if-condition-int.rs:+1:8: +1:9
+      debug x => _1;                       // in scope 0 at $DIR/if_condition_int.rs:+0:17: +0:18
+      let mut _0: u32;                     // return place in scope 0 at $DIR/if_condition_int.rs:+0:28: +0:31
+      let mut _2: bool;                    // in scope 0 at $DIR/if_condition_int.rs:+1:8: +1:16
+      let mut _3: i32;                     // in scope 0 at $DIR/if_condition_int.rs:+1:8: +1:9
   
       bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:16
-          StorageLive(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:9
-          _3 = _1;                         // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:9
--         _2 = Eq(move _3, const -42_i32); // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:16
--         StorageDead(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:15: +1:16
--         switchInt(move _2) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:16
-+         nop;                             // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:16
-+         nop;                             // scope 0 at $DIR/if-condition-int.rs:+1:15: +1:16
-+         switchInt(move _3) -> [-42_i32: bb1, otherwise: bb2]; // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:16
+          StorageLive(_2);                 // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:16
+          StorageLive(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:9
+          _3 = _1;                         // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:9
+-         _2 = Eq(move _3, const -42_i32); // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:16
+-         StorageDead(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:15: +1:16
+-         switchInt(move _2) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:16
++         nop;                             // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:16
++         nop;                             // scope 0 at $DIR/if_condition_int.rs:+1:15: +1:16
++         switchInt(move _3) -> [-42_i32: bb1, otherwise: bb2]; // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:16
       }
   
       bb1: {
-+         StorageDead(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:16
-          _0 = const 0_u32;                // scope 0 at $DIR/if-condition-int.rs:+1:19: +1:20
-          goto -> bb3;                     // scope 0 at $DIR/if-condition-int.rs:+1:5: +1:33
++         StorageDead(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:16
+          _0 = const 0_u32;                // scope 0 at $DIR/if_condition_int.rs:+1:19: +1:20
+          goto -> bb3;                     // scope 0 at $DIR/if_condition_int.rs:+1:5: +1:33
       }
   
       bb2: {
-+         StorageDead(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:16
-          _0 = const 1_u32;                // scope 0 at $DIR/if-condition-int.rs:+1:30: +1:31
-          goto -> bb3;                     // scope 0 at $DIR/if-condition-int.rs:+1:5: +1:33
++         StorageDead(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:16
+          _0 = const 1_u32;                // scope 0 at $DIR/if_condition_int.rs:+1:30: +1:31
+          goto -> bb3;                     // scope 0 at $DIR/if_condition_int.rs:+1:5: +1:33
       }
   
       bb3: {
-          StorageDead(_2);                 // scope 0 at $DIR/if-condition-int.rs:+1:32: +1:33
-          return;                          // scope 0 at $DIR/if-condition-int.rs:+2:2: +2:2
+          StorageDead(_2);                 // scope 0 at $DIR/if_condition_int.rs:+1:32: +1:33
+          return;                          // scope 0 at $DIR/if_condition_int.rs:+2:2: +2:2
       }
   }
   
diff --git a/src/test/mir-opt/if_condition_int.opt_u32.SimplifyComparisonIntegral.diff b/src/test/mir-opt/if_condition_int.opt_u32.SimplifyComparisonIntegral.diff
index 96387771d06f..7cea9472d3a0 100644
--- a/src/test/mir-opt/if_condition_int.opt_u32.SimplifyComparisonIntegral.diff
+++ b/src/test/mir-opt/if_condition_int.opt_u32.SimplifyComparisonIntegral.diff
@@ -2,38 +2,38 @@
 + // MIR for `opt_u32` after SimplifyComparisonIntegral
   
   fn opt_u32(_1: u32) -> u32 {
-      debug x => _1;                       // in scope 0 at $DIR/if-condition-int.rs:+0:12: +0:13
-      let mut _0: u32;                     // return place in scope 0 at $DIR/if-condition-int.rs:+0:23: +0:26
-      let mut _2: bool;                    // in scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
-      let mut _3: u32;                     // in scope 0 at $DIR/if-condition-int.rs:+1:8: +1:9
+      debug x => _1;                       // in scope 0 at $DIR/if_condition_int.rs:+0:12: +0:13
+      let mut _0: u32;                     // return place in scope 0 at $DIR/if_condition_int.rs:+0:23: +0:26
+      let mut _2: bool;                    // in scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
+      let mut _3: u32;                     // in scope 0 at $DIR/if_condition_int.rs:+1:8: +1:9
   
       bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
-          StorageLive(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:9
-          _3 = _1;                         // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:9
--         _2 = Eq(move _3, const 42_u32);  // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
--         StorageDead(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:14: +1:15
--         switchInt(move _2) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
-+         nop;                             // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
-+         nop;                             // scope 0 at $DIR/if-condition-int.rs:+1:14: +1:15
-+         switchInt(move _3) -> [42_u32: bb1, otherwise: bb2]; // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
+          StorageLive(_2);                 // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
+          StorageLive(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:9
+          _3 = _1;                         // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:9
+-         _2 = Eq(move _3, const 42_u32);  // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
+-         StorageDead(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:14: +1:15
+-         switchInt(move _2) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
++         nop;                             // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
++         nop;                             // scope 0 at $DIR/if_condition_int.rs:+1:14: +1:15
++         switchInt(move _3) -> [42_u32: bb1, otherwise: bb2]; // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
       }
   
       bb1: {
-+         StorageDead(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
-          _0 = const 0_u32;                // scope 0 at $DIR/if-condition-int.rs:+1:18: +1:19
-          goto -> bb3;                     // scope 0 at $DIR/if-condition-int.rs:+1:5: +1:32
++         StorageDead(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
+          _0 = const 0_u32;                // scope 0 at $DIR/if_condition_int.rs:+1:18: +1:19
+          goto -> bb3;                     // scope 0 at $DIR/if_condition_int.rs:+1:5: +1:32
       }
   
       bb2: {
-+         StorageDead(_3);                 // scope 0 at $DIR/if-condition-int.rs:+1:8: +1:15
-          _0 = const 1_u32;                // scope 0 at $DIR/if-condition-int.rs:+1:29: +1:30
-          goto -> bb3;                     // scope 0 at $DIR/if-condition-int.rs:+1:5: +1:32
++         StorageDead(_3);                 // scope 0 at $DIR/if_condition_int.rs:+1:8: +1:15
+          _0 = const 1_u32;                // scope 0 at $DIR/if_condition_int.rs:+1:29: +1:30
+          goto -> bb3;                     // scope 0 at $DIR/if_condition_int.rs:+1:5: +1:32
       }
   
       bb3: {
-          StorageDead(_2);                 // scope 0 at $DIR/if-condition-int.rs:+1:31: +1:32
-          return;                          // scope 0 at $DIR/if-condition-int.rs:+2:2: +2:2
+          StorageDead(_2);                 // scope 0 at $DIR/if_condition_int.rs:+1:31: +1:32
+          return;                          // scope 0 at $DIR/if_condition_int.rs:+2:2: +2:2
       }
   }
   
diff --git a/src/test/mir-opt/if-condition-int.rs b/src/test/mir-opt/if_condition_int.rs
similarity index 100%
rename from src/test/mir-opt/if-condition-int.rs
rename to src/test/mir-opt/if_condition_int.rs
diff --git a/src/test/mir-opt/inline/asm_unwind.main.Inline.diff b/src/test/mir-opt/inline/asm_unwind.main.Inline.diff
index 57072fc0ad39..f1b62ac38ba4 100644
--- a/src/test/mir-opt/inline/asm_unwind.main.Inline.diff
+++ b/src/test/mir-opt/inline/asm_unwind.main.Inline.diff
@@ -2,44 +2,44 @@
 + // MIR for `main` after Inline
   
   fn main() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/asm-unwind.rs:+0:15: +0:15
-      let _1: ();                          // in scope 0 at $DIR/asm-unwind.rs:+1:5: +1:10
-+     scope 1 (inlined foo) {              // at $DIR/asm-unwind.rs:21:5: 21:10
-+         let _2: D;                       // in scope 1 at $DIR/asm-unwind.rs:15:9: 15:11
+      let mut _0: ();                      // return place in scope 0 at $DIR/asm_unwind.rs:+0:15: +0:15
+      let _1: ();                          // in scope 0 at $DIR/asm_unwind.rs:+1:5: +1:10
++     scope 1 (inlined foo) {              // at $DIR/asm_unwind.rs:21:5: 21:10
++         let _2: D;                       // in scope 1 at $DIR/asm_unwind.rs:15:9: 15:11
 +         scope 2 {
-+             debug _d => _2;              // in scope 2 at $DIR/asm-unwind.rs:15:9: 15:11
++             debug _d => _2;              // in scope 2 at $DIR/asm_unwind.rs:15:9: 15:11
 +             scope 3 {
 +             }
 +         }
 +     }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/asm-unwind.rs:+1:5: +1:10
--         _1 = foo() -> bb1;               // scope 0 at $DIR/asm-unwind.rs:+1:5: +1:10
+          StorageLive(_1);                 // scope 0 at $DIR/asm_unwind.rs:+1:5: +1:10
+-         _1 = foo() -> bb1;               // scope 0 at $DIR/asm_unwind.rs:+1:5: +1:10
 -                                          // mir::Constant
--                                          // + span: $DIR/asm-unwind.rs:21:5: 21:8
+-                                          // + span: $DIR/asm_unwind.rs:21:5: 21:8
 -                                          // + literal: Const { ty: fn() {foo}, val: Value(<ZST>) }
-+         StorageLive(_2);                 // scope 1 at $DIR/asm-unwind.rs:15:9: 15:11
-+         asm!("", options(MAY_UNWIND)) -> [return: bb1, unwind: bb3]; // scope 3 at $DIR/asm-unwind.rs:16:14: 16:54
++         StorageLive(_2);                 // scope 1 at $DIR/asm_unwind.rs:15:9: 15:11
++         asm!("", options(MAY_UNWIND)) -> [return: bb1, unwind: bb3]; // scope 3 at $DIR/asm_unwind.rs:16:14: 16:54
       }
   
       bb1: {
-+         drop(_2) -> bb2;                 // scope 1 at $DIR/asm-unwind.rs:17:1: 17:2
++         drop(_2) -> bb2;                 // scope 1 at $DIR/asm_unwind.rs:17:1: 17:2
 +     }
 + 
 +     bb2: {
-+         StorageDead(_2);                 // scope 1 at $DIR/asm-unwind.rs:17:1: 17:2
-          StorageDead(_1);                 // scope 0 at $DIR/asm-unwind.rs:+1:10: +1:11
-          _0 = const ();                   // scope 0 at $DIR/asm-unwind.rs:+0:15: +2:2
-          return;                          // scope 0 at $DIR/asm-unwind.rs:+2:2: +2:2
++         StorageDead(_2);                 // scope 1 at $DIR/asm_unwind.rs:17:1: 17:2
+          StorageDead(_1);                 // scope 0 at $DIR/asm_unwind.rs:+1:10: +1:11
+          _0 = const ();                   // scope 0 at $DIR/asm_unwind.rs:+0:15: +2:2
+          return;                          // scope 0 at $DIR/asm_unwind.rs:+2:2: +2:2
 +     }
 + 
 +     bb3 (cleanup): {
-+         drop(_2) -> bb4;                 // scope 1 at $DIR/asm-unwind.rs:17:1: 17:2
++         drop(_2) -> bb4;                 // scope 1 at $DIR/asm_unwind.rs:17:1: 17:2
 +     }
 + 
 +     bb4 (cleanup): {
-+         resume;                          // scope 1 at $DIR/asm-unwind.rs:14:1: 17:2
++         resume;                          // scope 1 at $DIR/asm_unwind.rs:14:1: 17:2
       }
   }
   
diff --git a/src/test/mir-opt/inline/asm-unwind.rs b/src/test/mir-opt/inline/asm_unwind.rs
similarity index 100%
rename from src/test/mir-opt/inline/asm-unwind.rs
rename to src/test/mir-opt/inline/asm_unwind.rs
diff --git a/src/test/mir-opt/inline/caller_with_trivial_bound.foo.Inline.diff b/src/test/mir-opt/inline/caller_with_trivial_bound.foo.Inline.diff
index d7deb9c66cfa..8b03006782b2 100644
--- a/src/test/mir-opt/inline/caller_with_trivial_bound.foo.Inline.diff
+++ b/src/test/mir-opt/inline/caller_with_trivial_bound.foo.Inline.diff
@@ -2,32 +2,32 @@
 + // MIR for `foo` after Inline
   
   fn foo() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/caller-with-trivial-bound.rs:+1:1: +1:1
-      let mut _1: <IntFactory as Factory<T>>::Item; // in scope 0 at $DIR/caller-with-trivial-bound.rs:+4:9: +4:14
+      let mut _0: ();                      // return place in scope 0 at $DIR/caller_with_trivial_bound.rs:+1:1: +1:1
+      let mut _1: <IntFactory as Factory<T>>::Item; // in scope 0 at $DIR/caller_with_trivial_bound.rs:+4:9: +4:14
       scope 1 {
-          debug x => _1;                   // in scope 1 at $DIR/caller-with-trivial-bound.rs:+4:9: +4:14
+          debug x => _1;                   // in scope 1 at $DIR/caller_with_trivial_bound.rs:+4:9: +4:14
       }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/caller-with-trivial-bound.rs:+4:9: +4:14
-          _1 = bar::<T>() -> bb1;          // scope 0 at $DIR/caller-with-trivial-bound.rs:+4:51: +4:61
+          StorageLive(_1);                 // scope 0 at $DIR/caller_with_trivial_bound.rs:+4:9: +4:14
+          _1 = bar::<T>() -> bb1;          // scope 0 at $DIR/caller_with_trivial_bound.rs:+4:51: +4:61
                                            // mir::Constant
-                                           // + span: $DIR/caller-with-trivial-bound.rs:20:51: 20:59
+                                           // + span: $DIR/caller_with_trivial_bound.rs:20:51: 20:59
                                            // + literal: Const { ty: fn() -> <IntFactory as Factory<T>>::Item {bar::<T>}, val: Value(<ZST>) }
       }
   
       bb1: {
-          _0 = const ();                   // scope 0 at $DIR/caller-with-trivial-bound.rs:+3:1: +5:2
-          drop(_1) -> [return: bb2, unwind: bb3]; // scope 0 at $DIR/caller-with-trivial-bound.rs:+5:1: +5:2
+          _0 = const ();                   // scope 0 at $DIR/caller_with_trivial_bound.rs:+3:1: +5:2
+          drop(_1) -> [return: bb2, unwind: bb3]; // scope 0 at $DIR/caller_with_trivial_bound.rs:+5:1: +5:2
       }
   
       bb2: {
-          StorageDead(_1);                 // scope 0 at $DIR/caller-with-trivial-bound.rs:+5:1: +5:2
-          return;                          // scope 0 at $DIR/caller-with-trivial-bound.rs:+5:2: +5:2
+          StorageDead(_1);                 // scope 0 at $DIR/caller_with_trivial_bound.rs:+5:1: +5:2
+          return;                          // scope 0 at $DIR/caller_with_trivial_bound.rs:+5:2: +5:2
       }
   
       bb3 (cleanup): {
-          resume;                          // scope 0 at $DIR/caller-with-trivial-bound.rs:+0:1: +5:2
+          resume;                          // scope 0 at $DIR/caller_with_trivial_bound.rs:+0:1: +5:2
       }
   }
   
diff --git a/src/test/mir-opt/inline/caller-with-trivial-bound.rs b/src/test/mir-opt/inline/caller_with_trivial_bound.rs
similarity index 100%
rename from src/test/mir-opt/inline/caller-with-trivial-bound.rs
rename to src/test/mir-opt/inline/caller_with_trivial_bound.rs
diff --git a/src/test/mir-opt/inline/dyn_trait.get_query.Inline.diff b/src/test/mir-opt/inline/dyn_trait.get_query.Inline.diff
index 1e95b5b29ff4..284306a352d1 100644
--- a/src/test/mir-opt/inline/dyn_trait.get_query.Inline.diff
+++ b/src/test/mir-opt/inline/dyn_trait.get_query.Inline.diff
@@ -2,61 +2,61 @@
 + // MIR for `get_query` after Inline
   
   fn get_query(_1: &T) -> () {
-      debug t => _1;                       // in scope 0 at $DIR/dyn-trait.rs:+0:31: +0:32
-      let mut _0: ();                      // return place in scope 0 at $DIR/dyn-trait.rs:+0:38: +0:38
-      let _2: &<Q as Query>::C;            // in scope 0 at $DIR/dyn-trait.rs:+1:9: +1:10
-      let mut _3: &T;                      // in scope 0 at $DIR/dyn-trait.rs:+1:22: +1:23
-      let mut _4: &<Q as Query>::C;        // in scope 0 at $DIR/dyn-trait.rs:+2:23: +2:24
+      debug t => _1;                       // in scope 0 at $DIR/dyn_trait.rs:+0:31: +0:32
+      let mut _0: ();                      // return place in scope 0 at $DIR/dyn_trait.rs:+0:38: +0:38
+      let _2: &<Q as Query>::C;            // in scope 0 at $DIR/dyn_trait.rs:+1:9: +1:10
+      let mut _3: &T;                      // in scope 0 at $DIR/dyn_trait.rs:+1:22: +1:23
+      let mut _4: &<Q as Query>::C;        // in scope 0 at $DIR/dyn_trait.rs:+2:23: +2:24
       scope 1 {
-          debug c => _2;                   // in scope 1 at $DIR/dyn-trait.rs:+1:9: +1:10
-+         scope 2 (inlined try_execute_query::<<Q as Query>::C>) { // at $DIR/dyn-trait.rs:34:5: 34:25
-+             debug c => _4;               // in scope 2 at $DIR/dyn-trait.rs:26:36: 26:37
-+             let mut _5: &dyn Cache<V = <Q as Query>::V>; // in scope 2 at $DIR/dyn-trait.rs:27:14: 27:15
-+             let mut _6: &<Q as Query>::C; // in scope 2 at $DIR/dyn-trait.rs:27:14: 27:15
-+             scope 3 (inlined mk_cycle::<<Q as Query>::V>) { // at $DIR/dyn-trait.rs:27:5: 27:16
-+                 debug c => _5;           // in scope 3 at $DIR/dyn-trait.rs:20:27: 20:28
-+                 let mut _7: &dyn Cache<V = <Q as Query>::V>; // in scope 3 at $DIR/dyn-trait.rs:21:5: 21:22
+          debug c => _2;                   // in scope 1 at $DIR/dyn_trait.rs:+1:9: +1:10
++         scope 2 (inlined try_execute_query::<<Q as Query>::C>) { // at $DIR/dyn_trait.rs:34:5: 34:25
++             debug c => _4;               // in scope 2 at $DIR/dyn_trait.rs:26:36: 26:37
++             let mut _5: &dyn Cache<V = <Q as Query>::V>; // in scope 2 at $DIR/dyn_trait.rs:27:14: 27:15
++             let mut _6: &<Q as Query>::C; // in scope 2 at $DIR/dyn_trait.rs:27:14: 27:15
++             scope 3 (inlined mk_cycle::<<Q as Query>::V>) { // at $DIR/dyn_trait.rs:27:5: 27:16
++                 debug c => _5;           // in scope 3 at $DIR/dyn_trait.rs:20:27: 20:28
++                 let mut _7: &dyn Cache<V = <Q as Query>::V>; // in scope 3 at $DIR/dyn_trait.rs:21:5: 21:22
 +             }
 +         }
       }
   
       bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/dyn-trait.rs:+1:9: +1:10
-          StorageLive(_3);                 // scope 0 at $DIR/dyn-trait.rs:+1:22: +1:23
-          _3 = &(*_1);                     // scope 0 at $DIR/dyn-trait.rs:+1:22: +1:23
-          _2 = <Q as Query>::cache::<T>(move _3) -> bb1; // scope 0 at $DIR/dyn-trait.rs:+1:13: +1:24
+          StorageLive(_2);                 // scope 0 at $DIR/dyn_trait.rs:+1:9: +1:10
+          StorageLive(_3);                 // scope 0 at $DIR/dyn_trait.rs:+1:22: +1:23
+          _3 = &(*_1);                     // scope 0 at $DIR/dyn_trait.rs:+1:22: +1:23
+          _2 = <Q as Query>::cache::<T>(move _3) -> bb1; // scope 0 at $DIR/dyn_trait.rs:+1:13: +1:24
                                            // mir::Constant
-                                           // + span: $DIR/dyn-trait.rs:33:13: 33:21
+                                           // + span: $DIR/dyn_trait.rs:33:13: 33:21
                                            // + user_ty: UserType(0)
                                            // + literal: Const { ty: for<'a> fn(&'a T) -> &'a <Q as Query>::C {<Q as Query>::cache::<T>}, val: Value(<ZST>) }
       }
   
       bb1: {
-          StorageDead(_3);                 // scope 0 at $DIR/dyn-trait.rs:+1:23: +1:24
-          StorageLive(_4);                 // scope 1 at $DIR/dyn-trait.rs:+2:23: +2:24
-          _4 = &(*_2);                     // scope 1 at $DIR/dyn-trait.rs:+2:23: +2:24
--         _0 = try_execute_query::<<Q as Query>::C>(move _4) -> bb2; // scope 1 at $DIR/dyn-trait.rs:+2:5: +2:25
-+         StorageLive(_5);                 // scope 2 at $DIR/dyn-trait.rs:27:14: 27:15
-+         StorageLive(_6);                 // scope 2 at $DIR/dyn-trait.rs:27:14: 27:15
-+         _6 = _4;                         // scope 2 at $DIR/dyn-trait.rs:27:14: 27:15
-+         _5 = move _6 as &dyn Cache<V = <Q as Query>::V> (Pointer(Unsize)); // scope 2 at $DIR/dyn-trait.rs:27:14: 27:15
-+         StorageDead(_6);                 // scope 2 at $DIR/dyn-trait.rs:27:14: 27:15
-+         StorageLive(_7);                 // scope 3 at $DIR/dyn-trait.rs:21:5: 21:22
-+         _7 = _5;                         // scope 3 at $DIR/dyn-trait.rs:21:5: 21:22
-+         _0 = <dyn Cache<V = <Q as Query>::V> as Cache>::store_nocache(move _7) -> bb2; // scope 3 at $DIR/dyn-trait.rs:21:5: 21:22
+          StorageDead(_3);                 // scope 0 at $DIR/dyn_trait.rs:+1:23: +1:24
+          StorageLive(_4);                 // scope 1 at $DIR/dyn_trait.rs:+2:23: +2:24
+          _4 = &(*_2);                     // scope 1 at $DIR/dyn_trait.rs:+2:23: +2:24
+-         _0 = try_execute_query::<<Q as Query>::C>(move _4) -> bb2; // scope 1 at $DIR/dyn_trait.rs:+2:5: +2:25
++         StorageLive(_5);                 // scope 2 at $DIR/dyn_trait.rs:27:14: 27:15
++         StorageLive(_6);                 // scope 2 at $DIR/dyn_trait.rs:27:14: 27:15
++         _6 = _4;                         // scope 2 at $DIR/dyn_trait.rs:27:14: 27:15
++         _5 = move _6 as &dyn Cache<V = <Q as Query>::V> (Pointer(Unsize)); // scope 2 at $DIR/dyn_trait.rs:27:14: 27:15
++         StorageDead(_6);                 // scope 2 at $DIR/dyn_trait.rs:27:14: 27:15
++         StorageLive(_7);                 // scope 3 at $DIR/dyn_trait.rs:21:5: 21:22
++         _7 = _5;                         // scope 3 at $DIR/dyn_trait.rs:21:5: 21:22
++         _0 = <dyn Cache<V = <Q as Query>::V> as Cache>::store_nocache(move _7) -> bb2; // scope 3 at $DIR/dyn_trait.rs:21:5: 21:22
                                            // mir::Constant
--                                          // + span: $DIR/dyn-trait.rs:34:5: 34:22
+-                                          // + span: $DIR/dyn_trait.rs:34:5: 34:22
 -                                          // + literal: Const { ty: for<'a> fn(&'a <Q as Query>::C) {try_execute_query::<<Q as Query>::C>}, val: Value(<ZST>) }
-+                                          // + span: $DIR/dyn-trait.rs:21:7: 21:20
++                                          // + span: $DIR/dyn_trait.rs:21:7: 21:20
 +                                          // + literal: Const { ty: for<'a> fn(&'a dyn Cache<V = <Q as Query>::V>) {<dyn Cache<V = <Q as Query>::V> as Cache>::store_nocache}, val: Value(<ZST>) }
       }
   
       bb2: {
-+         StorageDead(_7);                 // scope 3 at $DIR/dyn-trait.rs:21:21: 21:22
-+         StorageDead(_5);                 // scope 2 at $DIR/dyn-trait.rs:27:15: 27:16
-          StorageDead(_4);                 // scope 1 at $DIR/dyn-trait.rs:+2:24: +2:25
-          StorageDead(_2);                 // scope 0 at $DIR/dyn-trait.rs:+3:1: +3:2
-          return;                          // scope 0 at $DIR/dyn-trait.rs:+3:2: +3:2
++         StorageDead(_7);                 // scope 3 at $DIR/dyn_trait.rs:21:21: 21:22
++         StorageDead(_5);                 // scope 2 at $DIR/dyn_trait.rs:27:15: 27:16
+          StorageDead(_4);                 // scope 1 at $DIR/dyn_trait.rs:+2:24: +2:25
+          StorageDead(_2);                 // scope 0 at $DIR/dyn_trait.rs:+3:1: +3:2
+          return;                          // scope 0 at $DIR/dyn_trait.rs:+3:2: +3:2
       }
   }
   
diff --git a/src/test/mir-opt/inline/dyn_trait.mk_cycle.Inline.diff b/src/test/mir-opt/inline/dyn_trait.mk_cycle.Inline.diff
index 7421db4d063a..7653a5ded440 100644
--- a/src/test/mir-opt/inline/dyn_trait.mk_cycle.Inline.diff
+++ b/src/test/mir-opt/inline/dyn_trait.mk_cycle.Inline.diff
@@ -2,22 +2,22 @@
 + // MIR for `mk_cycle` after Inline
   
   fn mk_cycle(_1: &dyn Cache<V = V>) -> () {
-      debug c => _1;                       // in scope 0 at $DIR/dyn-trait.rs:+0:27: +0:28
-      let mut _0: ();                      // return place in scope 0 at $DIR/dyn-trait.rs:+0:49: +0:49
-      let mut _2: &dyn Cache<V = V>;       // in scope 0 at $DIR/dyn-trait.rs:+1:5: +1:22
+      debug c => _1;                       // in scope 0 at $DIR/dyn_trait.rs:+0:27: +0:28
+      let mut _0: ();                      // return place in scope 0 at $DIR/dyn_trait.rs:+0:49: +0:49
+      let mut _2: &dyn Cache<V = V>;       // in scope 0 at $DIR/dyn_trait.rs:+1:5: +1:22
   
       bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/dyn-trait.rs:+1:5: +1:22
-          _2 = &(*_1);                     // scope 0 at $DIR/dyn-trait.rs:+1:5: +1:22
-          _0 = <dyn Cache<V = V> as Cache>::store_nocache(move _2) -> bb1; // scope 0 at $DIR/dyn-trait.rs:+1:5: +1:22
+          StorageLive(_2);                 // scope 0 at $DIR/dyn_trait.rs:+1:5: +1:22
+          _2 = &(*_1);                     // scope 0 at $DIR/dyn_trait.rs:+1:5: +1:22
+          _0 = <dyn Cache<V = V> as Cache>::store_nocache(move _2) -> bb1; // scope 0 at $DIR/dyn_trait.rs:+1:5: +1:22
                                            // mir::Constant
-                                           // + span: $DIR/dyn-trait.rs:21:7: 21:20
+                                           // + span: $DIR/dyn_trait.rs:21:7: 21:20
                                            // + literal: Const { ty: for<'a> fn(&'a dyn Cache<V = V>) {<dyn Cache<V = V> as Cache>::store_nocache}, val: Value(<ZST>) }
       }
   
       bb1: {
-          StorageDead(_2);                 // scope 0 at $DIR/dyn-trait.rs:+1:21: +1:22
-          return;                          // scope 0 at $DIR/dyn-trait.rs:+2:2: +2:2
+          StorageDead(_2);                 // scope 0 at $DIR/dyn_trait.rs:+1:21: +1:22
+          return;                          // scope 0 at $DIR/dyn_trait.rs:+2:2: +2:2
       }
   }
   
diff --git a/src/test/mir-opt/inline/dyn-trait.rs b/src/test/mir-opt/inline/dyn_trait.rs
similarity index 100%
rename from src/test/mir-opt/inline/dyn-trait.rs
rename to src/test/mir-opt/inline/dyn_trait.rs
diff --git a/src/test/mir-opt/inline/dyn_trait.try_execute_query.Inline.diff b/src/test/mir-opt/inline/dyn_trait.try_execute_query.Inline.diff
index e6e783744227..0191045f3d1a 100644
--- a/src/test/mir-opt/inline/dyn_trait.try_execute_query.Inline.diff
+++ b/src/test/mir-opt/inline/dyn_trait.try_execute_query.Inline.diff
@@ -2,36 +2,36 @@
 + // MIR for `try_execute_query` after Inline
   
   fn try_execute_query(_1: &C) -> () {
-      debug c => _1;                       // in scope 0 at $DIR/dyn-trait.rs:+0:36: +0:37
-      let mut _0: ();                      // return place in scope 0 at $DIR/dyn-trait.rs:+0:43: +0:43
-      let mut _2: &dyn Cache<V = <C as Cache>::V>; // in scope 0 at $DIR/dyn-trait.rs:+1:14: +1:15
-      let mut _3: &C;                      // in scope 0 at $DIR/dyn-trait.rs:+1:14: +1:15
-+     scope 1 (inlined mk_cycle::<<C as Cache>::V>) { // at $DIR/dyn-trait.rs:27:5: 27:16
-+         debug c => _2;                   // in scope 1 at $DIR/dyn-trait.rs:20:27: 20:28
-+         let mut _4: &dyn Cache<V = <C as Cache>::V>; // in scope 1 at $DIR/dyn-trait.rs:21:5: 21:22
+      debug c => _1;                       // in scope 0 at $DIR/dyn_trait.rs:+0:36: +0:37
+      let mut _0: ();                      // return place in scope 0 at $DIR/dyn_trait.rs:+0:43: +0:43
+      let mut _2: &dyn Cache<V = <C as Cache>::V>; // in scope 0 at $DIR/dyn_trait.rs:+1:14: +1:15
+      let mut _3: &C;                      // in scope 0 at $DIR/dyn_trait.rs:+1:14: +1:15
++     scope 1 (inlined mk_cycle::<<C as Cache>::V>) { // at $DIR/dyn_trait.rs:27:5: 27:16
++         debug c => _2;                   // in scope 1 at $DIR/dyn_trait.rs:20:27: 20:28
++         let mut _4: &dyn Cache<V = <C as Cache>::V>; // in scope 1 at $DIR/dyn_trait.rs:21:5: 21:22
 +     }
   
       bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/dyn-trait.rs:+1:14: +1:15
-          StorageLive(_3);                 // scope 0 at $DIR/dyn-trait.rs:+1:14: +1:15
-          _3 = &(*_1);                     // scope 0 at $DIR/dyn-trait.rs:+1:14: +1:15
-          _2 = move _3 as &dyn Cache<V = <C as Cache>::V> (Pointer(Unsize)); // scope 0 at $DIR/dyn-trait.rs:+1:14: +1:15
-          StorageDead(_3);                 // scope 0 at $DIR/dyn-trait.rs:+1:14: +1:15
--         _0 = mk_cycle::<<C as Cache>::V>(move _2) -> bb1; // scope 0 at $DIR/dyn-trait.rs:+1:5: +1:16
-+         StorageLive(_4);                 // scope 1 at $DIR/dyn-trait.rs:21:5: 21:22
-+         _4 = _2;                         // scope 1 at $DIR/dyn-trait.rs:21:5: 21:22
-+         _0 = <dyn Cache<V = <C as Cache>::V> as Cache>::store_nocache(move _4) -> bb1; // scope 1 at $DIR/dyn-trait.rs:21:5: 21:22
+          StorageLive(_2);                 // scope 0 at $DIR/dyn_trait.rs:+1:14: +1:15
+          StorageLive(_3);                 // scope 0 at $DIR/dyn_trait.rs:+1:14: +1:15
+          _3 = &(*_1);                     // scope 0 at $DIR/dyn_trait.rs:+1:14: +1:15
+          _2 = move _3 as &dyn Cache<V = <C as Cache>::V> (Pointer(Unsize)); // scope 0 at $DIR/dyn_trait.rs:+1:14: +1:15
+          StorageDead(_3);                 // scope 0 at $DIR/dyn_trait.rs:+1:14: +1:15
+-         _0 = mk_cycle::<<C as Cache>::V>(move _2) -> bb1; // scope 0 at $DIR/dyn_trait.rs:+1:5: +1:16
++         StorageLive(_4);                 // scope 1 at $DIR/dyn_trait.rs:21:5: 21:22
++         _4 = _2;                         // scope 1 at $DIR/dyn_trait.rs:21:5: 21:22
++         _0 = <dyn Cache<V = <C as Cache>::V> as Cache>::store_nocache(move _4) -> bb1; // scope 1 at $DIR/dyn_trait.rs:21:5: 21:22
                                            // mir::Constant
--                                          // + span: $DIR/dyn-trait.rs:27:5: 27:13
+-                                          // + span: $DIR/dyn_trait.rs:27:5: 27:13
 -                                          // + literal: Const { ty: for<'a> fn(&'a (dyn Cache<V = <C as Cache>::V> + 'a)) {mk_cycle::<<C as Cache>::V>}, val: Value(<ZST>) }
-+                                          // + span: $DIR/dyn-trait.rs:21:7: 21:20
++                                          // + span: $DIR/dyn_trait.rs:21:7: 21:20
 +                                          // + literal: Const { ty: for<'a> fn(&'a dyn Cache<V = <C as Cache>::V>) {<dyn Cache<V = <C as Cache>::V> as Cache>::store_nocache}, val: Value(<ZST>) }
       }
   
       bb1: {
-+         StorageDead(_4);                 // scope 1 at $DIR/dyn-trait.rs:21:21: 21:22
-          StorageDead(_2);                 // scope 0 at $DIR/dyn-trait.rs:+1:15: +1:16
-          return;                          // scope 0 at $DIR/dyn-trait.rs:+2:2: +2:2
++         StorageDead(_4);                 // scope 1 at $DIR/dyn_trait.rs:21:21: 21:22
+          StorageDead(_2);                 // scope 0 at $DIR/dyn_trait.rs:+1:15: +1:16
+          return;                          // scope 0 at $DIR/dyn_trait.rs:+2:2: +2:2
       }
   }
   
diff --git a/src/test/mir-opt/inline/inline_any_operand.bar.Inline.after.mir b/src/test/mir-opt/inline/inline_any_operand.bar.Inline.after.mir
index b27425fb18c2..8956c80dcd2a 100644
--- a/src/test/mir-opt/inline/inline_any_operand.bar.Inline.after.mir
+++ b/src/test/mir-opt/inline/inline_any_operand.bar.Inline.after.mir
@@ -1,44 +1,44 @@
 // MIR for `bar` after Inline
 
 fn bar() -> bool {
-    let mut _0: bool;                    // return place in scope 0 at $DIR/inline-any-operand.rs:+0:13: +0:17
-    let _1: fn(i32, i32) -> bool {foo};  // in scope 0 at $DIR/inline-any-operand.rs:+1:9: +1:10
-    let mut _2: fn(i32, i32) -> bool {foo}; // in scope 0 at $DIR/inline-any-operand.rs:+2:5: +2:6
-    let mut _3: i32;                     // in scope 0 at $DIR/inline-any-operand.rs:+2:5: +2:13
-    let mut _4: i32;                     // in scope 0 at $DIR/inline-any-operand.rs:+2:5: +2:13
+    let mut _0: bool;                    // return place in scope 0 at $DIR/inline_any_operand.rs:+0:13: +0:17
+    let _1: fn(i32, i32) -> bool {foo};  // in scope 0 at $DIR/inline_any_operand.rs:+1:9: +1:10
+    let mut _2: fn(i32, i32) -> bool {foo}; // in scope 0 at $DIR/inline_any_operand.rs:+2:5: +2:6
+    let mut _3: i32;                     // in scope 0 at $DIR/inline_any_operand.rs:+2:5: +2:13
+    let mut _4: i32;                     // in scope 0 at $DIR/inline_any_operand.rs:+2:5: +2:13
     scope 1 {
-        debug f => _1;                   // in scope 1 at $DIR/inline-any-operand.rs:+1:9: +1:10
-        scope 2 (inlined foo) {          // at $DIR/inline-any-operand.rs:12:5: 12:13
-            debug x => _3;               // in scope 2 at $DIR/inline-any-operand.rs:16:8: 16:9
-            debug y => _4;               // in scope 2 at $DIR/inline-any-operand.rs:16:16: 16:17
-            let mut _5: i32;             // in scope 2 at $DIR/inline-any-operand.rs:17:5: 17:6
-            let mut _6: i32;             // in scope 2 at $DIR/inline-any-operand.rs:17:10: 17:11
+        debug f => _1;                   // in scope 1 at $DIR/inline_any_operand.rs:+1:9: +1:10
+        scope 2 (inlined foo) {          // at $DIR/inline_any_operand.rs:12:5: 12:13
+            debug x => _3;               // in scope 2 at $DIR/inline_any_operand.rs:16:8: 16:9
+            debug y => _4;               // in scope 2 at $DIR/inline_any_operand.rs:16:16: 16:17
+            let mut _5: i32;             // in scope 2 at $DIR/inline_any_operand.rs:17:5: 17:6
+            let mut _6: i32;             // in scope 2 at $DIR/inline_any_operand.rs:17:10: 17:11
         }
     }
 
     bb0: {
-        StorageLive(_1);                 // scope 0 at $DIR/inline-any-operand.rs:+1:9: +1:10
-        _1 = foo;                        // scope 0 at $DIR/inline-any-operand.rs:+1:13: +1:16
+        StorageLive(_1);                 // scope 0 at $DIR/inline_any_operand.rs:+1:9: +1:10
+        _1 = foo;                        // scope 0 at $DIR/inline_any_operand.rs:+1:13: +1:16
                                          // mir::Constant
-                                         // + span: $DIR/inline-any-operand.rs:11:13: 11:16
+                                         // + span: $DIR/inline_any_operand.rs:11:13: 11:16
                                          // + literal: Const { ty: fn(i32, i32) -> bool {foo}, val: Value(<ZST>) }
-        StorageLive(_2);                 // scope 1 at $DIR/inline-any-operand.rs:+2:5: +2:6
-        _2 = _1;                         // scope 1 at $DIR/inline-any-operand.rs:+2:5: +2:6
-        StorageLive(_3);                 // scope 1 at $DIR/inline-any-operand.rs:+2:5: +2:13
-        _3 = const 1_i32;                // scope 1 at $DIR/inline-any-operand.rs:+2:5: +2:13
-        StorageLive(_4);                 // scope 1 at $DIR/inline-any-operand.rs:+2:5: +2:13
-        _4 = const -1_i32;               // scope 1 at $DIR/inline-any-operand.rs:+2:5: +2:13
-        StorageLive(_5);                 // scope 2 at $DIR/inline-any-operand.rs:17:5: 17:6
-        _5 = _3;                         // scope 2 at $DIR/inline-any-operand.rs:17:5: 17:6
-        StorageLive(_6);                 // scope 2 at $DIR/inline-any-operand.rs:17:10: 17:11
-        _6 = _4;                         // scope 2 at $DIR/inline-any-operand.rs:17:10: 17:11
-        _0 = Eq(move _5, move _6);       // scope 2 at $DIR/inline-any-operand.rs:17:5: 17:11
-        StorageDead(_6);                 // scope 2 at $DIR/inline-any-operand.rs:17:10: 17:11
-        StorageDead(_5);                 // scope 2 at $DIR/inline-any-operand.rs:17:10: 17:11
-        StorageDead(_4);                 // scope 1 at $DIR/inline-any-operand.rs:+2:5: +2:13
-        StorageDead(_3);                 // scope 1 at $DIR/inline-any-operand.rs:+2:5: +2:13
-        StorageDead(_2);                 // scope 1 at $DIR/inline-any-operand.rs:+2:12: +2:13
-        StorageDead(_1);                 // scope 0 at $DIR/inline-any-operand.rs:+3:1: +3:2
-        return;                          // scope 0 at $DIR/inline-any-operand.rs:+3:2: +3:2
+        StorageLive(_2);                 // scope 1 at $DIR/inline_any_operand.rs:+2:5: +2:6
+        _2 = _1;                         // scope 1 at $DIR/inline_any_operand.rs:+2:5: +2:6
+        StorageLive(_3);                 // scope 1 at $DIR/inline_any_operand.rs:+2:5: +2:13
+        _3 = const 1_i32;                // scope 1 at $DIR/inline_any_operand.rs:+2:5: +2:13
+        StorageLive(_4);                 // scope 1 at $DIR/inline_any_operand.rs:+2:5: +2:13
+        _4 = const -1_i32;               // scope 1 at $DIR/inline_any_operand.rs:+2:5: +2:13
+        StorageLive(_5);                 // scope 2 at $DIR/inline_any_operand.rs:17:5: 17:6
+        _5 = _3;                         // scope 2 at $DIR/inline_any_operand.rs:17:5: 17:6
+        StorageLive(_6);                 // scope 2 at $DIR/inline_any_operand.rs:17:10: 17:11
+        _6 = _4;                         // scope 2 at $DIR/inline_any_operand.rs:17:10: 17:11
+        _0 = Eq(move _5, move _6);       // scope 2 at $DIR/inline_any_operand.rs:17:5: 17:11
+        StorageDead(_6);                 // scope 2 at $DIR/inline_any_operand.rs:17:10: 17:11
+        StorageDead(_5);                 // scope 2 at $DIR/inline_any_operand.rs:17:10: 17:11
+        StorageDead(_4);                 // scope 1 at $DIR/inline_any_operand.rs:+2:5: +2:13
+        StorageDead(_3);                 // scope 1 at $DIR/inline_any_operand.rs:+2:5: +2:13
+        StorageDead(_2);                 // scope 1 at $DIR/inline_any_operand.rs:+2:12: +2:13
+        StorageDead(_1);                 // scope 0 at $DIR/inline_any_operand.rs:+3:1: +3:2
+        return;                          // scope 0 at $DIR/inline_any_operand.rs:+3:2: +3:2
     }
 }
diff --git a/src/test/mir-opt/inline/inline-any-operand.rs b/src/test/mir-opt/inline/inline_any_operand.rs
similarity index 100%
rename from src/test/mir-opt/inline/inline-any-operand.rs
rename to src/test/mir-opt/inline/inline_any_operand.rs
diff --git a/src/test/mir-opt/inline/inline-async.rs b/src/test/mir-opt/inline/inline_async.rs
similarity index 100%
rename from src/test/mir-opt/inline/inline-async.rs
rename to src/test/mir-opt/inline/inline_async.rs
diff --git a/src/test/mir-opt/inline/inline_closure.foo.Inline.after.mir b/src/test/mir-opt/inline/inline_closure.foo.Inline.after.mir
index 1fadd2464798..9eb3a01eef91 100644
--- a/src/test/mir-opt/inline/inline_closure.foo.Inline.after.mir
+++ b/src/test/mir-opt/inline/inline_closure.foo.Inline.after.mir
@@ -1,49 +1,49 @@
 // MIR for `foo` after Inline
 
 fn foo(_1: T, _2: i32) -> i32 {
-    debug _t => _1;                      // in scope 0 at $DIR/inline-closure.rs:+0:17: +0:19
-    debug q => _2;                       // in scope 0 at $DIR/inline-closure.rs:+0:24: +0:25
-    let mut _0: i32;                     // return place in scope 0 at $DIR/inline-closure.rs:+0:35: +0:38
-    let _3: [closure@foo<T>::{closure#0}]; // in scope 0 at $DIR/inline-closure.rs:+1:9: +1:10
-    let mut _4: &[closure@foo<T>::{closure#0}]; // in scope 0 at $DIR/inline-closure.rs:+2:5: +2:6
-    let mut _5: (i32, i32);              // in scope 0 at $DIR/inline-closure.rs:+2:5: +2:12
-    let mut _6: i32;                     // in scope 0 at $DIR/inline-closure.rs:+2:7: +2:8
-    let mut _7: i32;                     // in scope 0 at $DIR/inline-closure.rs:+2:10: +2:11
-    let mut _8: i32;                     // in scope 0 at $DIR/inline-closure.rs:+2:5: +2:12
-    let mut _9: i32;                     // in scope 0 at $DIR/inline-closure.rs:+2:5: +2:12
+    debug _t => _1;                      // in scope 0 at $DIR/inline_closure.rs:+0:17: +0:19
+    debug q => _2;                       // in scope 0 at $DIR/inline_closure.rs:+0:24: +0:25
+    let mut _0: i32;                     // return place in scope 0 at $DIR/inline_closure.rs:+0:35: +0:38
+    let _3: [closure@foo<T>::{closure#0}]; // in scope 0 at $DIR/inline_closure.rs:+1:9: +1:10
+    let mut _4: &[closure@foo<T>::{closure#0}]; // in scope 0 at $DIR/inline_closure.rs:+2:5: +2:6
+    let mut _5: (i32, i32);              // in scope 0 at $DIR/inline_closure.rs:+2:5: +2:12
+    let mut _6: i32;                     // in scope 0 at $DIR/inline_closure.rs:+2:7: +2:8
+    let mut _7: i32;                     // in scope 0 at $DIR/inline_closure.rs:+2:10: +2:11
+    let mut _8: i32;                     // in scope 0 at $DIR/inline_closure.rs:+2:5: +2:12
+    let mut _9: i32;                     // in scope 0 at $DIR/inline_closure.rs:+2:5: +2:12
     scope 1 {
-        debug x => _3;                   // in scope 1 at $DIR/inline-closure.rs:+1:9: +1:10
-        scope 2 (inlined foo::<T>::{closure#0}) { // at $DIR/inline-closure.rs:12:5: 12:12
-            debug _t => _8;              // in scope 2 at $DIR/inline-closure.rs:+1:14: +1:16
-            debug _q => _9;              // in scope 2 at $DIR/inline-closure.rs:+1:18: +1:20
+        debug x => _3;                   // in scope 1 at $DIR/inline_closure.rs:+1:9: +1:10
+        scope 2 (inlined foo::<T>::{closure#0}) { // at $DIR/inline_closure.rs:12:5: 12:12
+            debug _t => _8;              // in scope 2 at $DIR/inline_closure.rs:+1:14: +1:16
+            debug _q => _9;              // in scope 2 at $DIR/inline_closure.rs:+1:18: +1:20
         }
     }
 
     bb0: {
-        StorageLive(_3);                 // scope 0 at $DIR/inline-closure.rs:+1:9: +1:10
-        Deinit(_3);                      // scope 0 at $DIR/inline-closure.rs:+1:13: +1:24
-        StorageLive(_4);                 // scope 1 at $DIR/inline-closure.rs:+2:5: +2:6
-        _4 = &_3;                        // scope 1 at $DIR/inline-closure.rs:+2:5: +2:6
-        StorageLive(_5);                 // scope 1 at $DIR/inline-closure.rs:+2:5: +2:12
-        StorageLive(_6);                 // scope 1 at $DIR/inline-closure.rs:+2:7: +2:8
-        _6 = _2;                         // scope 1 at $DIR/inline-closure.rs:+2:7: +2:8
-        StorageLive(_7);                 // scope 1 at $DIR/inline-closure.rs:+2:10: +2:11
-        _7 = _2;                         // scope 1 at $DIR/inline-closure.rs:+2:10: +2:11
-        Deinit(_5);                      // scope 1 at $DIR/inline-closure.rs:+2:5: +2:12
-        (_5.0: i32) = move _6;           // scope 1 at $DIR/inline-closure.rs:+2:5: +2:12
-        (_5.1: i32) = move _7;           // scope 1 at $DIR/inline-closure.rs:+2:5: +2:12
-        StorageLive(_8);                 // scope 1 at $DIR/inline-closure.rs:+2:5: +2:12
-        _8 = move (_5.0: i32);           // scope 1 at $DIR/inline-closure.rs:+2:5: +2:12
-        StorageLive(_9);                 // scope 1 at $DIR/inline-closure.rs:+2:5: +2:12
-        _9 = move (_5.1: i32);           // scope 1 at $DIR/inline-closure.rs:+2:5: +2:12
-        _0 = _8;                         // scope 2 at $DIR/inline-closure.rs:+1:22: +1:24
-        StorageDead(_9);                 // scope 1 at $DIR/inline-closure.rs:+2:5: +2:12
-        StorageDead(_8);                 // scope 1 at $DIR/inline-closure.rs:+2:5: +2:12
-        StorageDead(_7);                 // scope 1 at $DIR/inline-closure.rs:+2:11: +2:12
-        StorageDead(_6);                 // scope 1 at $DIR/inline-closure.rs:+2:11: +2:12
-        StorageDead(_5);                 // scope 1 at $DIR/inline-closure.rs:+2:11: +2:12
-        StorageDead(_4);                 // scope 1 at $DIR/inline-closure.rs:+2:11: +2:12
-        StorageDead(_3);                 // scope 0 at $DIR/inline-closure.rs:+3:1: +3:2
-        return;                          // scope 0 at $DIR/inline-closure.rs:+3:2: +3:2
+        StorageLive(_3);                 // scope 0 at $DIR/inline_closure.rs:+1:9: +1:10
+        Deinit(_3);                      // scope 0 at $DIR/inline_closure.rs:+1:13: +1:24
+        StorageLive(_4);                 // scope 1 at $DIR/inline_closure.rs:+2:5: +2:6
+        _4 = &_3;                        // scope 1 at $DIR/inline_closure.rs:+2:5: +2:6
+        StorageLive(_5);                 // scope 1 at $DIR/inline_closure.rs:+2:5: +2:12
+        StorageLive(_6);                 // scope 1 at $DIR/inline_closure.rs:+2:7: +2:8
+        _6 = _2;                         // scope 1 at $DIR/inline_closure.rs:+2:7: +2:8
+        StorageLive(_7);                 // scope 1 at $DIR/inline_closure.rs:+2:10: +2:11
+        _7 = _2;                         // scope 1 at $DIR/inline_closure.rs:+2:10: +2:11
+        Deinit(_5);                      // scope 1 at $DIR/inline_closure.rs:+2:5: +2:12
+        (_5.0: i32) = move _6;           // scope 1 at $DIR/inline_closure.rs:+2:5: +2:12
+        (_5.1: i32) = move _7;           // scope 1 at $DIR/inline_closure.rs:+2:5: +2:12
+        StorageLive(_8);                 // scope 1 at $DIR/inline_closure.rs:+2:5: +2:12
+        _8 = move (_5.0: i32);           // scope 1 at $DIR/inline_closure.rs:+2:5: +2:12
+        StorageLive(_9);                 // scope 1 at $DIR/inline_closure.rs:+2:5: +2:12
+        _9 = move (_5.1: i32);           // scope 1 at $DIR/inline_closure.rs:+2:5: +2:12
+        _0 = _8;                         // scope 2 at $DIR/inline_closure.rs:+1:22: +1:24
+        StorageDead(_9);                 // scope 1 at $DIR/inline_closure.rs:+2:5: +2:12
+        StorageDead(_8);                 // scope 1 at $DIR/inline_closure.rs:+2:5: +2:12
+        StorageDead(_7);                 // scope 1 at $DIR/inline_closure.rs:+2:11: +2:12
+        StorageDead(_6);                 // scope 1 at $DIR/inline_closure.rs:+2:11: +2:12
+        StorageDead(_5);                 // scope 1 at $DIR/inline_closure.rs:+2:11: +2:12
+        StorageDead(_4);                 // scope 1 at $DIR/inline_closure.rs:+2:11: +2:12
+        StorageDead(_3);                 // scope 0 at $DIR/inline_closure.rs:+3:1: +3:2
+        return;                          // scope 0 at $DIR/inline_closure.rs:+3:2: +3:2
     }
 }
diff --git a/src/test/mir-opt/inline/inline-closure.rs b/src/test/mir-opt/inline/inline_closure.rs
similarity index 100%
rename from src/test/mir-opt/inline/inline-closure.rs
rename to src/test/mir-opt/inline/inline_closure.rs
diff --git a/src/test/mir-opt/inline/inline_closure_borrows_arg.foo.Inline.after.mir b/src/test/mir-opt/inline/inline_closure_borrows_arg.foo.Inline.after.mir
index 4069e9f89c8d..e6275ac7f5dd 100644
--- a/src/test/mir-opt/inline/inline_closure_borrows_arg.foo.Inline.after.mir
+++ b/src/test/mir-opt/inline/inline_closure_borrows_arg.foo.Inline.after.mir
@@ -1,56 +1,56 @@
 // MIR for `foo` after Inline
 
 fn foo(_1: T, _2: &i32) -> i32 {
-    debug _t => _1;                      // in scope 0 at $DIR/inline-closure-borrows-arg.rs:+0:17: +0:19
-    debug q => _2;                       // in scope 0 at $DIR/inline-closure-borrows-arg.rs:+0:24: +0:25
-    let mut _0: i32;                     // return place in scope 0 at $DIR/inline-closure-borrows-arg.rs:+0:36: +0:39
-    let _3: [closure@foo<T>::{closure#0}]; // in scope 0 at $DIR/inline-closure-borrows-arg.rs:+1:9: +1:10
-    let mut _4: &[closure@foo<T>::{closure#0}]; // in scope 0 at $DIR/inline-closure-borrows-arg.rs:+5:5: +5:6
-    let mut _5: (&i32, &i32);            // in scope 0 at $DIR/inline-closure-borrows-arg.rs:+5:5: +5:12
-    let mut _6: &i32;                    // in scope 0 at $DIR/inline-closure-borrows-arg.rs:+5:7: +5:8
-    let mut _7: &i32;                    // in scope 0 at $DIR/inline-closure-borrows-arg.rs:+5:10: +5:11
-    let mut _8: &i32;                    // in scope 0 at $DIR/inline-closure-borrows-arg.rs:+5:5: +5:12
-    let mut _9: &i32;                    // in scope 0 at $DIR/inline-closure-borrows-arg.rs:+5:5: +5:12
+    debug _t => _1;                      // in scope 0 at $DIR/inline_closure_borrows_arg.rs:+0:17: +0:19
+    debug q => _2;                       // in scope 0 at $DIR/inline_closure_borrows_arg.rs:+0:24: +0:25
+    let mut _0: i32;                     // return place in scope 0 at $DIR/inline_closure_borrows_arg.rs:+0:36: +0:39
+    let _3: [closure@foo<T>::{closure#0}]; // in scope 0 at $DIR/inline_closure_borrows_arg.rs:+1:9: +1:10
+    let mut _4: &[closure@foo<T>::{closure#0}]; // in scope 0 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:6
+    let mut _5: (&i32, &i32);            // in scope 0 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:12
+    let mut _6: &i32;                    // in scope 0 at $DIR/inline_closure_borrows_arg.rs:+5:7: +5:8
+    let mut _7: &i32;                    // in scope 0 at $DIR/inline_closure_borrows_arg.rs:+5:10: +5:11
+    let mut _8: &i32;                    // in scope 0 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:12
+    let mut _9: &i32;                    // in scope 0 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:12
     scope 1 {
-        debug x => _3;                   // in scope 1 at $DIR/inline-closure-borrows-arg.rs:+1:9: +1:10
-        scope 2 (inlined foo::<T>::{closure#0}) { // at $DIR/inline-closure-borrows-arg.rs:16:5: 16:12
-            debug r => _8;               // in scope 2 at $DIR/inline-closure-borrows-arg.rs:+1:14: +1:15
-            debug _s => _9;              // in scope 2 at $DIR/inline-closure-borrows-arg.rs:+1:23: +1:25
-            let _10: &i32;               // in scope 2 at $DIR/inline-closure-borrows-arg.rs:+2:13: +2:21
+        debug x => _3;                   // in scope 1 at $DIR/inline_closure_borrows_arg.rs:+1:9: +1:10
+        scope 2 (inlined foo::<T>::{closure#0}) { // at $DIR/inline_closure_borrows_arg.rs:16:5: 16:12
+            debug r => _8;               // in scope 2 at $DIR/inline_closure_borrows_arg.rs:+1:14: +1:15
+            debug _s => _9;              // in scope 2 at $DIR/inline_closure_borrows_arg.rs:+1:23: +1:25
+            let _10: &i32;               // in scope 2 at $DIR/inline_closure_borrows_arg.rs:+2:13: +2:21
             scope 3 {
-                debug variable => _10;   // in scope 3 at $DIR/inline-closure-borrows-arg.rs:+2:13: +2:21
+                debug variable => _10;   // in scope 3 at $DIR/inline_closure_borrows_arg.rs:+2:13: +2:21
             }
         }
     }
 
     bb0: {
-        StorageLive(_3);                 // scope 0 at $DIR/inline-closure-borrows-arg.rs:+1:9: +1:10
-        Deinit(_3);                      // scope 0 at $DIR/inline-closure-borrows-arg.rs:+1:13: +4:6
-        StorageLive(_4);                 // scope 1 at $DIR/inline-closure-borrows-arg.rs:+5:5: +5:6
-        _4 = &_3;                        // scope 1 at $DIR/inline-closure-borrows-arg.rs:+5:5: +5:6
-        StorageLive(_5);                 // scope 1 at $DIR/inline-closure-borrows-arg.rs:+5:5: +5:12
-        StorageLive(_6);                 // scope 1 at $DIR/inline-closure-borrows-arg.rs:+5:7: +5:8
-        _6 = &(*_2);                     // scope 1 at $DIR/inline-closure-borrows-arg.rs:+5:7: +5:8
-        StorageLive(_7);                 // scope 1 at $DIR/inline-closure-borrows-arg.rs:+5:10: +5:11
-        _7 = &(*_2);                     // scope 1 at $DIR/inline-closure-borrows-arg.rs:+5:10: +5:11
-        Deinit(_5);                      // scope 1 at $DIR/inline-closure-borrows-arg.rs:+5:5: +5:12
-        (_5.0: &i32) = move _6;          // scope 1 at $DIR/inline-closure-borrows-arg.rs:+5:5: +5:12
-        (_5.1: &i32) = move _7;          // scope 1 at $DIR/inline-closure-borrows-arg.rs:+5:5: +5:12
-        StorageLive(_8);                 // scope 1 at $DIR/inline-closure-borrows-arg.rs:+5:5: +5:12
-        _8 = move (_5.0: &i32);          // scope 1 at $DIR/inline-closure-borrows-arg.rs:+5:5: +5:12
-        StorageLive(_9);                 // scope 1 at $DIR/inline-closure-borrows-arg.rs:+5:5: +5:12
-        _9 = move (_5.1: &i32);          // scope 1 at $DIR/inline-closure-borrows-arg.rs:+5:5: +5:12
-        StorageLive(_10);                // scope 2 at $DIR/inline-closure-borrows-arg.rs:+2:13: +2:21
-        _10 = _8;                        // scope 2 at $DIR/inline-closure-borrows-arg.rs:+2:24: +2:27
-        _0 = (*_10);                     // scope 3 at $DIR/inline-closure-borrows-arg.rs:+3:9: +3:18
-        StorageDead(_10);                // scope 2 at $DIR/inline-closure-borrows-arg.rs:+4:5: +4:6
-        StorageDead(_9);                 // scope 1 at $DIR/inline-closure-borrows-arg.rs:+5:5: +5:12
-        StorageDead(_8);                 // scope 1 at $DIR/inline-closure-borrows-arg.rs:+5:5: +5:12
-        StorageDead(_7);                 // scope 1 at $DIR/inline-closure-borrows-arg.rs:+5:11: +5:12
-        StorageDead(_6);                 // scope 1 at $DIR/inline-closure-borrows-arg.rs:+5:11: +5:12
-        StorageDead(_5);                 // scope 1 at $DIR/inline-closure-borrows-arg.rs:+5:11: +5:12
-        StorageDead(_4);                 // scope 1 at $DIR/inline-closure-borrows-arg.rs:+5:11: +5:12
-        StorageDead(_3);                 // scope 0 at $DIR/inline-closure-borrows-arg.rs:+6:1: +6:2
-        return;                          // scope 0 at $DIR/inline-closure-borrows-arg.rs:+6:2: +6:2
+        StorageLive(_3);                 // scope 0 at $DIR/inline_closure_borrows_arg.rs:+1:9: +1:10
+        Deinit(_3);                      // scope 0 at $DIR/inline_closure_borrows_arg.rs:+1:13: +4:6
+        StorageLive(_4);                 // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:6
+        _4 = &_3;                        // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:6
+        StorageLive(_5);                 // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:12
+        StorageLive(_6);                 // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:7: +5:8
+        _6 = &(*_2);                     // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:7: +5:8
+        StorageLive(_7);                 // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:10: +5:11
+        _7 = &(*_2);                     // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:10: +5:11
+        Deinit(_5);                      // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:12
+        (_5.0: &i32) = move _6;          // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:12
+        (_5.1: &i32) = move _7;          // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:12
+        StorageLive(_8);                 // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:12
+        _8 = move (_5.0: &i32);          // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:12
+        StorageLive(_9);                 // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:12
+        _9 = move (_5.1: &i32);          // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:12
+        StorageLive(_10);                // scope 2 at $DIR/inline_closure_borrows_arg.rs:+2:13: +2:21
+        _10 = _8;                        // scope 2 at $DIR/inline_closure_borrows_arg.rs:+2:24: +2:27
+        _0 = (*_10);                     // scope 3 at $DIR/inline_closure_borrows_arg.rs:+3:9: +3:18
+        StorageDead(_10);                // scope 2 at $DIR/inline_closure_borrows_arg.rs:+4:5: +4:6
+        StorageDead(_9);                 // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:12
+        StorageDead(_8);                 // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:12
+        StorageDead(_7);                 // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:11: +5:12
+        StorageDead(_6);                 // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:11: +5:12
+        StorageDead(_5);                 // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:11: +5:12
+        StorageDead(_4);                 // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:11: +5:12
+        StorageDead(_3);                 // scope 0 at $DIR/inline_closure_borrows_arg.rs:+6:1: +6:2
+        return;                          // scope 0 at $DIR/inline_closure_borrows_arg.rs:+6:2: +6:2
     }
 }
diff --git a/src/test/mir-opt/inline/inline-closure-borrows-arg.rs b/src/test/mir-opt/inline/inline_closure_borrows_arg.rs
similarity index 100%
rename from src/test/mir-opt/inline/inline-closure-borrows-arg.rs
rename to src/test/mir-opt/inline/inline_closure_borrows_arg.rs
diff --git a/src/test/mir-opt/inline/inline_closure_captures.foo.Inline.after.mir b/src/test/mir-opt/inline/inline_closure_captures.foo.Inline.after.mir
index a2234e7c1eff..fd19c288666b 100644
--- a/src/test/mir-opt/inline/inline_closure_captures.foo.Inline.after.mir
+++ b/src/test/mir-opt/inline/inline_closure_captures.foo.Inline.after.mir
@@ -1,65 +1,65 @@
 // MIR for `foo` after Inline
 
 fn foo(_1: T, _2: i32) -> (i32, T) {
-    debug t => _1;                       // in scope 0 at $DIR/inline-closure-captures.rs:+0:17: +0:18
-    debug q => _2;                       // in scope 0 at $DIR/inline-closure-captures.rs:+0:23: +0:24
-    let mut _0: (i32, T);                // return place in scope 0 at $DIR/inline-closure-captures.rs:+0:34: +0:42
-    let _3: [closure@foo<T>::{closure#0}]; // in scope 0 at $DIR/inline-closure-captures.rs:+1:9: +1:10
-    let mut _4: &i32;                    // in scope 0 at $DIR/inline-closure-captures.rs:+1:13: +1:24
-    let mut _5: &T;                      // in scope 0 at $DIR/inline-closure-captures.rs:+1:13: +1:24
-    let mut _6: &[closure@foo<T>::{closure#0}]; // in scope 0 at $DIR/inline-closure-captures.rs:+2:5: +2:6
-    let mut _7: (i32,);                  // in scope 0 at $DIR/inline-closure-captures.rs:+2:5: +2:9
-    let mut _8: i32;                     // in scope 0 at $DIR/inline-closure-captures.rs:+2:7: +2:8
-    let mut _9: i32;                     // in scope 0 at $DIR/inline-closure-captures.rs:+2:5: +2:9
+    debug t => _1;                       // in scope 0 at $DIR/inline_closure_captures.rs:+0:17: +0:18
+    debug q => _2;                       // in scope 0 at $DIR/inline_closure_captures.rs:+0:23: +0:24
+    let mut _0: (i32, T);                // return place in scope 0 at $DIR/inline_closure_captures.rs:+0:34: +0:42
+    let _3: [closure@foo<T>::{closure#0}]; // in scope 0 at $DIR/inline_closure_captures.rs:+1:9: +1:10
+    let mut _4: &i32;                    // in scope 0 at $DIR/inline_closure_captures.rs:+1:13: +1:24
+    let mut _5: &T;                      // in scope 0 at $DIR/inline_closure_captures.rs:+1:13: +1:24
+    let mut _6: &[closure@foo<T>::{closure#0}]; // in scope 0 at $DIR/inline_closure_captures.rs:+2:5: +2:6
+    let mut _7: (i32,);                  // in scope 0 at $DIR/inline_closure_captures.rs:+2:5: +2:9
+    let mut _8: i32;                     // in scope 0 at $DIR/inline_closure_captures.rs:+2:7: +2:8
+    let mut _9: i32;                     // in scope 0 at $DIR/inline_closure_captures.rs:+2:5: +2:9
     scope 1 {
-        debug x => _3;                   // in scope 1 at $DIR/inline-closure-captures.rs:+1:9: +1:10
-        scope 2 (inlined foo::<T>::{closure#0}) { // at $DIR/inline-closure-captures.rs:12:5: 12:9
-            debug _q => _9;              // in scope 2 at $DIR/inline-closure-captures.rs:+1:14: +1:16
-            debug q => (*((*_6).0: &i32)); // in scope 2 at $DIR/inline-closure-captures.rs:+0:23: +0:24
-            debug t => (*((*_6).1: &T)); // in scope 2 at $DIR/inline-closure-captures.rs:+0:17: +0:18
-            let mut _10: i32;            // in scope 2 at $DIR/inline-closure-captures.rs:+1:19: +1:20
-            let mut _11: T;              // in scope 2 at $DIR/inline-closure-captures.rs:+1:22: +1:23
-            let mut _12: &i32;           // in scope 2 at $DIR/inline-closure-captures.rs:+1:13: +1:24
-            let mut _13: &T;             // in scope 2 at $DIR/inline-closure-captures.rs:+1:13: +1:24
+        debug x => _3;                   // in scope 1 at $DIR/inline_closure_captures.rs:+1:9: +1:10
+        scope 2 (inlined foo::<T>::{closure#0}) { // at $DIR/inline_closure_captures.rs:12:5: 12:9
+            debug _q => _9;              // in scope 2 at $DIR/inline_closure_captures.rs:+1:14: +1:16
+            debug q => (*((*_6).0: &i32)); // in scope 2 at $DIR/inline_closure_captures.rs:+0:23: +0:24
+            debug t => (*((*_6).1: &T)); // in scope 2 at $DIR/inline_closure_captures.rs:+0:17: +0:18
+            let mut _10: i32;            // in scope 2 at $DIR/inline_closure_captures.rs:+1:19: +1:20
+            let mut _11: T;              // in scope 2 at $DIR/inline_closure_captures.rs:+1:22: +1:23
+            let mut _12: &i32;           // in scope 2 at $DIR/inline_closure_captures.rs:+1:13: +1:24
+            let mut _13: &T;             // in scope 2 at $DIR/inline_closure_captures.rs:+1:13: +1:24
         }
     }
 
     bb0: {
-        StorageLive(_3);                 // scope 0 at $DIR/inline-closure-captures.rs:+1:9: +1:10
-        StorageLive(_4);                 // scope 0 at $DIR/inline-closure-captures.rs:+1:13: +1:24
-        _4 = &_2;                        // scope 0 at $DIR/inline-closure-captures.rs:+1:13: +1:24
-        StorageLive(_5);                 // scope 0 at $DIR/inline-closure-captures.rs:+1:13: +1:24
-        _5 = &_1;                        // scope 0 at $DIR/inline-closure-captures.rs:+1:13: +1:24
-        Deinit(_3);                      // scope 0 at $DIR/inline-closure-captures.rs:+1:13: +1:24
-        (_3.0: &i32) = move _4;          // scope 0 at $DIR/inline-closure-captures.rs:+1:13: +1:24
-        (_3.1: &T) = move _5;            // scope 0 at $DIR/inline-closure-captures.rs:+1:13: +1:24
-        StorageDead(_5);                 // scope 0 at $DIR/inline-closure-captures.rs:+1:16: +1:17
-        StorageDead(_4);                 // scope 0 at $DIR/inline-closure-captures.rs:+1:16: +1:17
-        StorageLive(_6);                 // scope 1 at $DIR/inline-closure-captures.rs:+2:5: +2:6
-        _6 = &_3;                        // scope 1 at $DIR/inline-closure-captures.rs:+2:5: +2:6
-        StorageLive(_7);                 // scope 1 at $DIR/inline-closure-captures.rs:+2:5: +2:9
-        StorageLive(_8);                 // scope 1 at $DIR/inline-closure-captures.rs:+2:7: +2:8
-        _8 = _2;                         // scope 1 at $DIR/inline-closure-captures.rs:+2:7: +2:8
-        Deinit(_7);                      // scope 1 at $DIR/inline-closure-captures.rs:+2:5: +2:9
-        (_7.0: i32) = move _8;           // scope 1 at $DIR/inline-closure-captures.rs:+2:5: +2:9
-        StorageLive(_9);                 // scope 1 at $DIR/inline-closure-captures.rs:+2:5: +2:9
-        _9 = move (_7.0: i32);           // scope 1 at $DIR/inline-closure-captures.rs:+2:5: +2:9
-        StorageLive(_10);                // scope 2 at $DIR/inline-closure-captures.rs:+1:19: +1:20
-        _12 = deref_copy ((*_6).0: &i32); // scope 2 at $DIR/inline-closure-captures.rs:+1:19: +1:20
-        _10 = (*_12);                    // scope 2 at $DIR/inline-closure-captures.rs:+1:19: +1:20
-        StorageLive(_11);                // scope 2 at $DIR/inline-closure-captures.rs:+1:22: +1:23
-        _13 = deref_copy ((*_6).1: &T);  // scope 2 at $DIR/inline-closure-captures.rs:+1:22: +1:23
-        _11 = (*_13);                    // scope 2 at $DIR/inline-closure-captures.rs:+1:22: +1:23
-        Deinit(_0);                      // scope 2 at $DIR/inline-closure-captures.rs:+1:18: +1:24
-        (_0.0: i32) = move _10;          // scope 2 at $DIR/inline-closure-captures.rs:+1:18: +1:24
-        (_0.1: T) = move _11;            // scope 2 at $DIR/inline-closure-captures.rs:+1:18: +1:24
-        StorageDead(_11);                // scope 2 at $DIR/inline-closure-captures.rs:+1:23: +1:24
-        StorageDead(_10);                // scope 2 at $DIR/inline-closure-captures.rs:+1:23: +1:24
-        StorageDead(_9);                 // scope 1 at $DIR/inline-closure-captures.rs:+2:5: +2:9
-        StorageDead(_8);                 // scope 1 at $DIR/inline-closure-captures.rs:+2:8: +2:9
-        StorageDead(_7);                 // scope 1 at $DIR/inline-closure-captures.rs:+2:8: +2:9
-        StorageDead(_6);                 // scope 1 at $DIR/inline-closure-captures.rs:+2:8: +2:9
-        StorageDead(_3);                 // scope 0 at $DIR/inline-closure-captures.rs:+3:1: +3:2
-        return;                          // scope 0 at $DIR/inline-closure-captures.rs:+3:2: +3:2
+        StorageLive(_3);                 // scope 0 at $DIR/inline_closure_captures.rs:+1:9: +1:10
+        StorageLive(_4);                 // scope 0 at $DIR/inline_closure_captures.rs:+1:13: +1:24
+        _4 = &_2;                        // scope 0 at $DIR/inline_closure_captures.rs:+1:13: +1:24
+        StorageLive(_5);                 // scope 0 at $DIR/inline_closure_captures.rs:+1:13: +1:24
+        _5 = &_1;                        // scope 0 at $DIR/inline_closure_captures.rs:+1:13: +1:24
+        Deinit(_3);                      // scope 0 at $DIR/inline_closure_captures.rs:+1:13: +1:24
+        (_3.0: &i32) = move _4;          // scope 0 at $DIR/inline_closure_captures.rs:+1:13: +1:24
+        (_3.1: &T) = move _5;            // scope 0 at $DIR/inline_closure_captures.rs:+1:13: +1:24
+        StorageDead(_5);                 // scope 0 at $DIR/inline_closure_captures.rs:+1:16: +1:17
+        StorageDead(_4);                 // scope 0 at $DIR/inline_closure_captures.rs:+1:16: +1:17
+        StorageLive(_6);                 // scope 1 at $DIR/inline_closure_captures.rs:+2:5: +2:6
+        _6 = &_3;                        // scope 1 at $DIR/inline_closure_captures.rs:+2:5: +2:6
+        StorageLive(_7);                 // scope 1 at $DIR/inline_closure_captures.rs:+2:5: +2:9
+        StorageLive(_8);                 // scope 1 at $DIR/inline_closure_captures.rs:+2:7: +2:8
+        _8 = _2;                         // scope 1 at $DIR/inline_closure_captures.rs:+2:7: +2:8
+        Deinit(_7);                      // scope 1 at $DIR/inline_closure_captures.rs:+2:5: +2:9
+        (_7.0: i32) = move _8;           // scope 1 at $DIR/inline_closure_captures.rs:+2:5: +2:9
+        StorageLive(_9);                 // scope 1 at $DIR/inline_closure_captures.rs:+2:5: +2:9
+        _9 = move (_7.0: i32);           // scope 1 at $DIR/inline_closure_captures.rs:+2:5: +2:9
+        StorageLive(_10);                // scope 2 at $DIR/inline_closure_captures.rs:+1:19: +1:20
+        _12 = deref_copy ((*_6).0: &i32); // scope 2 at $DIR/inline_closure_captures.rs:+1:19: +1:20
+        _10 = (*_12);                    // scope 2 at $DIR/inline_closure_captures.rs:+1:19: +1:20
+        StorageLive(_11);                // scope 2 at $DIR/inline_closure_captures.rs:+1:22: +1:23
+        _13 = deref_copy ((*_6).1: &T);  // scope 2 at $DIR/inline_closure_captures.rs:+1:22: +1:23
+        _11 = (*_13);                    // scope 2 at $DIR/inline_closure_captures.rs:+1:22: +1:23
+        Deinit(_0);                      // scope 2 at $DIR/inline_closure_captures.rs:+1:18: +1:24
+        (_0.0: i32) = move _10;          // scope 2 at $DIR/inline_closure_captures.rs:+1:18: +1:24
+        (_0.1: T) = move _11;            // scope 2 at $DIR/inline_closure_captures.rs:+1:18: +1:24
+        StorageDead(_11);                // scope 2 at $DIR/inline_closure_captures.rs:+1:23: +1:24
+        StorageDead(_10);                // scope 2 at $DIR/inline_closure_captures.rs:+1:23: +1:24
+        StorageDead(_9);                 // scope 1 at $DIR/inline_closure_captures.rs:+2:5: +2:9
+        StorageDead(_8);                 // scope 1 at $DIR/inline_closure_captures.rs:+2:8: +2:9
+        StorageDead(_7);                 // scope 1 at $DIR/inline_closure_captures.rs:+2:8: +2:9
+        StorageDead(_6);                 // scope 1 at $DIR/inline_closure_captures.rs:+2:8: +2:9
+        StorageDead(_3);                 // scope 0 at $DIR/inline_closure_captures.rs:+3:1: +3:2
+        return;                          // scope 0 at $DIR/inline_closure_captures.rs:+3:2: +3:2
     }
 }
diff --git a/src/test/mir-opt/inline/inline-closure-captures.rs b/src/test/mir-opt/inline/inline_closure_captures.rs
similarity index 100%
rename from src/test/mir-opt/inline/inline-closure-captures.rs
rename to src/test/mir-opt/inline/inline_closure_captures.rs
diff --git a/src/test/mir-opt/inline/inline_compatibility.inlined_no_sanitize.Inline.diff b/src/test/mir-opt/inline/inline_compatibility.inlined_no_sanitize.Inline.diff
index cf800ba11294..e30a5e116ea4 100644
--- a/src/test/mir-opt/inline/inline_compatibility.inlined_no_sanitize.Inline.diff
+++ b/src/test/mir-opt/inline/inline_compatibility.inlined_no_sanitize.Inline.diff
@@ -2,23 +2,23 @@
 + // MIR for `inlined_no_sanitize` after Inline
   
   fn inlined_no_sanitize() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/inline-compatibility.rs:+0:37: +0:37
-      let _1: ();                          // in scope 0 at $DIR/inline-compatibility.rs:+1:5: +1:18
-+     scope 1 (inlined no_sanitize) {      // at $DIR/inline-compatibility.rs:24:5: 24:18
+      let mut _0: ();                      // return place in scope 0 at $DIR/inline_compatibility.rs:+0:37: +0:37
+      let _1: ();                          // in scope 0 at $DIR/inline_compatibility.rs:+1:5: +1:18
++     scope 1 (inlined no_sanitize) {      // at $DIR/inline_compatibility.rs:24:5: 24:18
 +     }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/inline-compatibility.rs:+1:5: +1:18
--         _1 = no_sanitize() -> bb1;       // scope 0 at $DIR/inline-compatibility.rs:+1:5: +1:18
+          StorageLive(_1);                 // scope 0 at $DIR/inline_compatibility.rs:+1:5: +1:18
+-         _1 = no_sanitize() -> bb1;       // scope 0 at $DIR/inline_compatibility.rs:+1:5: +1:18
 -                                          // mir::Constant
--                                          // + span: $DIR/inline-compatibility.rs:24:5: 24:16
+-                                          // + span: $DIR/inline_compatibility.rs:24:5: 24:16
 -                                          // + literal: Const { ty: unsafe fn() {no_sanitize}, val: Value(<ZST>) }
 -     }
 - 
 -     bb1: {
-          StorageDead(_1);                 // scope 0 at $DIR/inline-compatibility.rs:+1:18: +1:19
-          _0 = const ();                   // scope 0 at $DIR/inline-compatibility.rs:+0:37: +2:2
-          return;                          // scope 0 at $DIR/inline-compatibility.rs:+2:2: +2:2
+          StorageDead(_1);                 // scope 0 at $DIR/inline_compatibility.rs:+1:18: +1:19
+          _0 = const ();                   // scope 0 at $DIR/inline_compatibility.rs:+0:37: +2:2
+          return;                          // scope 0 at $DIR/inline_compatibility.rs:+2:2: +2:2
       }
   }
   
diff --git a/src/test/mir-opt/inline/inline_compatibility.inlined_target_feature.Inline.diff b/src/test/mir-opt/inline/inline_compatibility.inlined_target_feature.Inline.diff
index a45f959026d1..c2b3c46a30c6 100644
--- a/src/test/mir-opt/inline/inline_compatibility.inlined_target_feature.Inline.diff
+++ b/src/test/mir-opt/inline/inline_compatibility.inlined_target_feature.Inline.diff
@@ -2,23 +2,23 @@
 + // MIR for `inlined_target_feature` after Inline
   
   fn inlined_target_feature() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/inline-compatibility.rs:+0:40: +0:40
-      let _1: ();                          // in scope 0 at $DIR/inline-compatibility.rs:+1:5: +1:21
-+     scope 1 (inlined target_feature) {   // at $DIR/inline-compatibility.rs:13:5: 13:21
+      let mut _0: ();                      // return place in scope 0 at $DIR/inline_compatibility.rs:+0:40: +0:40
+      let _1: ();                          // in scope 0 at $DIR/inline_compatibility.rs:+1:5: +1:21
++     scope 1 (inlined target_feature) {   // at $DIR/inline_compatibility.rs:13:5: 13:21
 +     }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/inline-compatibility.rs:+1:5: +1:21
--         _1 = target_feature() -> bb1;    // scope 0 at $DIR/inline-compatibility.rs:+1:5: +1:21
+          StorageLive(_1);                 // scope 0 at $DIR/inline_compatibility.rs:+1:5: +1:21
+-         _1 = target_feature() -> bb1;    // scope 0 at $DIR/inline_compatibility.rs:+1:5: +1:21
 -                                          // mir::Constant
--                                          // + span: $DIR/inline-compatibility.rs:13:5: 13:19
+-                                          // + span: $DIR/inline_compatibility.rs:13:5: 13:19
 -                                          // + literal: Const { ty: unsafe fn() {target_feature}, val: Value(<ZST>) }
 -     }
 - 
 -     bb1: {
-          StorageDead(_1);                 // scope 0 at $DIR/inline-compatibility.rs:+1:21: +1:22
-          _0 = const ();                   // scope 0 at $DIR/inline-compatibility.rs:+0:40: +2:2
-          return;                          // scope 0 at $DIR/inline-compatibility.rs:+2:2: +2:2
+          StorageDead(_1);                 // scope 0 at $DIR/inline_compatibility.rs:+1:21: +1:22
+          _0 = const ();                   // scope 0 at $DIR/inline_compatibility.rs:+0:40: +2:2
+          return;                          // scope 0 at $DIR/inline_compatibility.rs:+2:2: +2:2
       }
   }
   
diff --git a/src/test/mir-opt/inline/inline_compatibility.not_inlined_c_variadic.Inline.diff b/src/test/mir-opt/inline/inline_compatibility.not_inlined_c_variadic.Inline.diff
index 49aea431e46d..0ca5a5f70b7f 100644
--- a/src/test/mir-opt/inline/inline_compatibility.not_inlined_c_variadic.Inline.diff
+++ b/src/test/mir-opt/inline/inline_compatibility.not_inlined_c_variadic.Inline.diff
@@ -2,24 +2,24 @@
 + // MIR for `not_inlined_c_variadic` after Inline
   
   fn not_inlined_c_variadic() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/inline-compatibility.rs:+0:40: +0:40
-      let _1: u32;                         // in scope 0 at $DIR/inline-compatibility.rs:+1:9: +1:10
+      let mut _0: ();                      // return place in scope 0 at $DIR/inline_compatibility.rs:+0:40: +0:40
+      let _1: u32;                         // in scope 0 at $DIR/inline_compatibility.rs:+1:9: +1:10
       scope 1 {
-          debug s => _1;                   // in scope 1 at $DIR/inline-compatibility.rs:+1:9: +1:10
+          debug s => _1;                   // in scope 1 at $DIR/inline_compatibility.rs:+1:9: +1:10
       }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/inline-compatibility.rs:+1:9: +1:10
-          _1 = sum(const 4_u32, const 4_u32, const 30_u32, const 200_u32, const 1000_u32) -> bb1; // scope 0 at $DIR/inline-compatibility.rs:+1:13: +1:52
+          StorageLive(_1);                 // scope 0 at $DIR/inline_compatibility.rs:+1:9: +1:10
+          _1 = sum(const 4_u32, const 4_u32, const 30_u32, const 200_u32, const 1000_u32) -> bb1; // scope 0 at $DIR/inline_compatibility.rs:+1:13: +1:52
                                            // mir::Constant
-                                           // + span: $DIR/inline-compatibility.rs:42:13: 42:16
+                                           // + span: $DIR/inline_compatibility.rs:42:13: 42:16
                                            // + literal: Const { ty: unsafe extern "C" fn(u32, ...) -> u32 {sum}, val: Value(<ZST>) }
       }
   
       bb1: {
-          _0 = const ();                   // scope 0 at $DIR/inline-compatibility.rs:+0:40: +2:2
-          StorageDead(_1);                 // scope 0 at $DIR/inline-compatibility.rs:+2:1: +2:2
-          return;                          // scope 0 at $DIR/inline-compatibility.rs:+2:2: +2:2
+          _0 = const ();                   // scope 0 at $DIR/inline_compatibility.rs:+0:40: +2:2
+          StorageDead(_1);                 // scope 0 at $DIR/inline_compatibility.rs:+2:1: +2:2
+          return;                          // scope 0 at $DIR/inline_compatibility.rs:+2:2: +2:2
       }
   }
   
diff --git a/src/test/mir-opt/inline/inline_compatibility.not_inlined_no_sanitize.Inline.diff b/src/test/mir-opt/inline/inline_compatibility.not_inlined_no_sanitize.Inline.diff
index 94ce574a94dc..00d405c77f91 100644
--- a/src/test/mir-opt/inline/inline_compatibility.not_inlined_no_sanitize.Inline.diff
+++ b/src/test/mir-opt/inline/inline_compatibility.not_inlined_no_sanitize.Inline.diff
@@ -2,21 +2,21 @@
 + // MIR for `not_inlined_no_sanitize` after Inline
   
   fn not_inlined_no_sanitize() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/inline-compatibility.rs:+0:41: +0:41
-      let _1: ();                          // in scope 0 at $DIR/inline-compatibility.rs:+1:5: +1:18
+      let mut _0: ();                      // return place in scope 0 at $DIR/inline_compatibility.rs:+0:41: +0:41
+      let _1: ();                          // in scope 0 at $DIR/inline_compatibility.rs:+1:5: +1:18
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/inline-compatibility.rs:+1:5: +1:18
-          _1 = no_sanitize() -> bb1;       // scope 0 at $DIR/inline-compatibility.rs:+1:5: +1:18
+          StorageLive(_1);                 // scope 0 at $DIR/inline_compatibility.rs:+1:5: +1:18
+          _1 = no_sanitize() -> bb1;       // scope 0 at $DIR/inline_compatibility.rs:+1:5: +1:18
                                            // mir::Constant
-                                           // + span: $DIR/inline-compatibility.rs:29:5: 29:16
+                                           // + span: $DIR/inline_compatibility.rs:29:5: 29:16
                                            // + literal: Const { ty: unsafe fn() {no_sanitize}, val: Value(<ZST>) }
       }
   
       bb1: {
-          StorageDead(_1);                 // scope 0 at $DIR/inline-compatibility.rs:+1:18: +1:19
-          _0 = const ();                   // scope 0 at $DIR/inline-compatibility.rs:+0:41: +2:2
-          return;                          // scope 0 at $DIR/inline-compatibility.rs:+2:2: +2:2
+          StorageDead(_1);                 // scope 0 at $DIR/inline_compatibility.rs:+1:18: +1:19
+          _0 = const ();                   // scope 0 at $DIR/inline_compatibility.rs:+0:41: +2:2
+          return;                          // scope 0 at $DIR/inline_compatibility.rs:+2:2: +2:2
       }
   }
   
diff --git a/src/test/mir-opt/inline/inline_compatibility.not_inlined_target_feature.Inline.diff b/src/test/mir-opt/inline/inline_compatibility.not_inlined_target_feature.Inline.diff
index 8506e257b3fe..8b9c86f5515a 100644
--- a/src/test/mir-opt/inline/inline_compatibility.not_inlined_target_feature.Inline.diff
+++ b/src/test/mir-opt/inline/inline_compatibility.not_inlined_target_feature.Inline.diff
@@ -2,21 +2,21 @@
 + // MIR for `not_inlined_target_feature` after Inline
   
   fn not_inlined_target_feature() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/inline-compatibility.rs:+0:44: +0:44
-      let _1: ();                          // in scope 0 at $DIR/inline-compatibility.rs:+1:5: +1:21
+      let mut _0: ();                      // return place in scope 0 at $DIR/inline_compatibility.rs:+0:44: +0:44
+      let _1: ();                          // in scope 0 at $DIR/inline_compatibility.rs:+1:5: +1:21
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/inline-compatibility.rs:+1:5: +1:21
-          _1 = target_feature() -> bb1;    // scope 0 at $DIR/inline-compatibility.rs:+1:5: +1:21
+          StorageLive(_1);                 // scope 0 at $DIR/inline_compatibility.rs:+1:5: +1:21
+          _1 = target_feature() -> bb1;    // scope 0 at $DIR/inline_compatibility.rs:+1:5: +1:21
                                            // mir::Constant
-                                           // + span: $DIR/inline-compatibility.rs:18:5: 18:19
+                                           // + span: $DIR/inline_compatibility.rs:18:5: 18:19
                                            // + literal: Const { ty: unsafe fn() {target_feature}, val: Value(<ZST>) }
       }
   
       bb1: {
-          StorageDead(_1);                 // scope 0 at $DIR/inline-compatibility.rs:+1:21: +1:22
-          _0 = const ();                   // scope 0 at $DIR/inline-compatibility.rs:+0:44: +2:2
-          return;                          // scope 0 at $DIR/inline-compatibility.rs:+2:2: +2:2
+          StorageDead(_1);                 // scope 0 at $DIR/inline_compatibility.rs:+1:21: +1:22
+          _0 = const ();                   // scope 0 at $DIR/inline_compatibility.rs:+0:44: +2:2
+          return;                          // scope 0 at $DIR/inline_compatibility.rs:+2:2: +2:2
       }
   }
   
diff --git a/src/test/mir-opt/inline/inline-compatibility.rs b/src/test/mir-opt/inline/inline_compatibility.rs
similarity index 100%
rename from src/test/mir-opt/inline/inline-compatibility.rs
rename to src/test/mir-opt/inline/inline_compatibility.rs
diff --git a/src/test/mir-opt/inline/inline_cycle.one.Inline.diff b/src/test/mir-opt/inline/inline_cycle.one.Inline.diff
index a4d706de0ba5..5510cd7bc8ce 100644
--- a/src/test/mir-opt/inline/inline_cycle.one.Inline.diff
+++ b/src/test/mir-opt/inline/inline_cycle.one.Inline.diff
@@ -2,29 +2,29 @@
 + // MIR for `one` after Inline
   
   fn one() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/inline-cycle.rs:+0:10: +0:10
-      let _1: ();                          // in scope 0 at $DIR/inline-cycle.rs:+1:5: +1:24
-+     scope 1 (inlined <C as Call>::call) { // at $DIR/inline-cycle.rs:14:5: 14:24
-+         scope 2 (inlined <A<C> as Call>::call) { // at $DIR/inline-cycle.rs:43:9: 43:23
-+             scope 3 (inlined <B<C> as Call>::call) { // at $DIR/inline-cycle.rs:28:9: 28:31
+      let mut _0: ();                      // return place in scope 0 at $DIR/inline_cycle.rs:+0:10: +0:10
+      let _1: ();                          // in scope 0 at $DIR/inline_cycle.rs:+1:5: +1:24
++     scope 1 (inlined <C as Call>::call) { // at $DIR/inline_cycle.rs:14:5: 14:24
++         scope 2 (inlined <A<C> as Call>::call) { // at $DIR/inline_cycle.rs:43:9: 43:23
++             scope 3 (inlined <B<C> as Call>::call) { // at $DIR/inline_cycle.rs:28:9: 28:31
 +             }
 +         }
 +     }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/inline-cycle.rs:+1:5: +1:24
--         _1 = <C as Call>::call() -> bb1; // scope 0 at $DIR/inline-cycle.rs:+1:5: +1:24
-+         _1 = <C as Call>::call() -> bb1; // scope 3 at $DIR/inline-cycle.rs:36:9: 36:28
+          StorageLive(_1);                 // scope 0 at $DIR/inline_cycle.rs:+1:5: +1:24
+-         _1 = <C as Call>::call() -> bb1; // scope 0 at $DIR/inline_cycle.rs:+1:5: +1:24
++         _1 = <C as Call>::call() -> bb1; // scope 3 at $DIR/inline_cycle.rs:36:9: 36:28
                                            // mir::Constant
--                                          // + span: $DIR/inline-cycle.rs:14:5: 14:22
-+                                          // + span: $DIR/inline-cycle.rs:36:9: 36:26
+-                                          // + span: $DIR/inline_cycle.rs:14:5: 14:22
++                                          // + span: $DIR/inline_cycle.rs:36:9: 36:26
                                            // + literal: Const { ty: fn() {<C as Call>::call}, val: Value(<ZST>) }
       }
   
       bb1: {
-          StorageDead(_1);                 // scope 0 at $DIR/inline-cycle.rs:+1:24: +1:25
-          _0 = const ();                   // scope 0 at $DIR/inline-cycle.rs:+0:10: +2:2
-          return;                          // scope 0 at $DIR/inline-cycle.rs:+2:2: +2:2
+          StorageDead(_1);                 // scope 0 at $DIR/inline_cycle.rs:+1:24: +1:25
+          _0 = const ();                   // scope 0 at $DIR/inline_cycle.rs:+0:10: +2:2
+          return;                          // scope 0 at $DIR/inline_cycle.rs:+2:2: +2:2
       }
   }
   
diff --git a/src/test/mir-opt/inline/inline-cycle.rs b/src/test/mir-opt/inline/inline_cycle.rs
similarity index 100%
rename from src/test/mir-opt/inline/inline-cycle.rs
rename to src/test/mir-opt/inline/inline_cycle.rs
diff --git a/src/test/mir-opt/inline/inline_cycle.two.Inline.diff b/src/test/mir-opt/inline/inline_cycle.two.Inline.diff
index b1a5b62ef1d3..eceeb96f79f0 100644
--- a/src/test/mir-opt/inline/inline_cycle.two.Inline.diff
+++ b/src/test/mir-opt/inline/inline_cycle.two.Inline.diff
@@ -2,54 +2,54 @@
 + // MIR for `two` after Inline
   
   fn two() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/inline-cycle.rs:+0:10: +0:10
-      let _1: ();                          // in scope 0 at $DIR/inline-cycle.rs:+1:5: +1:12
-+     let mut _2: fn() {f};                // in scope 0 at $DIR/inline-cycle.rs:+1:5: +1:12
-+     scope 1 (inlined call::<fn() {f}>) { // at $DIR/inline-cycle.rs:49:5: 49:12
-+         debug f => _2;                   // in scope 1 at $DIR/inline-cycle.rs:53:22: 53:23
-+         let _3: ();                      // in scope 1 at $DIR/inline-cycle.rs:54:5: 54:8
-+         let mut _4: fn() {f};            // in scope 1 at $DIR/inline-cycle.rs:54:5: 54:6
-+         let mut _5: ();                  // in scope 1 at $DIR/inline-cycle.rs:54:5: 54:8
-+         scope 2 (inlined <fn() {f} as FnOnce<()>>::call_once - shim(fn() {f})) { // at $DIR/inline-cycle.rs:54:5: 54:8
+      let mut _0: ();                      // return place in scope 0 at $DIR/inline_cycle.rs:+0:10: +0:10
+      let _1: ();                          // in scope 0 at $DIR/inline_cycle.rs:+1:5: +1:12
++     let mut _2: fn() {f};                // in scope 0 at $DIR/inline_cycle.rs:+1:5: +1:12
++     scope 1 (inlined call::<fn() {f}>) { // at $DIR/inline_cycle.rs:49:5: 49:12
++         debug f => _2;                   // in scope 1 at $DIR/inline_cycle.rs:53:22: 53:23
++         let _3: ();                      // in scope 1 at $DIR/inline_cycle.rs:54:5: 54:8
++         let mut _4: fn() {f};            // in scope 1 at $DIR/inline_cycle.rs:54:5: 54:6
++         let mut _5: ();                  // in scope 1 at $DIR/inline_cycle.rs:54:5: 54:8
++         scope 2 (inlined <fn() {f} as FnOnce<()>>::call_once - shim(fn() {f})) { // at $DIR/inline_cycle.rs:54:5: 54:8
 +             scope 3 (inlined f) {        // at $SRC_DIR/core/src/ops/function.rs:LL:COL
-+                 let _6: ();              // in scope 3 at $DIR/inline-cycle.rs:59:5: 59:12
++                 let _6: ();              // in scope 3 at $DIR/inline_cycle.rs:59:5: 59:12
 +             }
 +         }
 +     }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/inline-cycle.rs:+1:5: +1:12
--         _1 = call::<fn() {f}>(f) -> bb1; // scope 0 at $DIR/inline-cycle.rs:+1:5: +1:12
-+         StorageLive(_2);                 // scope 0 at $DIR/inline-cycle.rs:+1:5: +1:12
-+         _2 = f;                          // scope 0 at $DIR/inline-cycle.rs:+1:5: +1:12
+          StorageLive(_1);                 // scope 0 at $DIR/inline_cycle.rs:+1:5: +1:12
+-         _1 = call::<fn() {f}>(f) -> bb1; // scope 0 at $DIR/inline_cycle.rs:+1:5: +1:12
++         StorageLive(_2);                 // scope 0 at $DIR/inline_cycle.rs:+1:5: +1:12
++         _2 = f;                          // scope 0 at $DIR/inline_cycle.rs:+1:5: +1:12
                                            // mir::Constant
--                                          // + span: $DIR/inline-cycle.rs:49:5: 49:9
-+                                          // + span: $DIR/inline-cycle.rs:49:10: 49:11
+-                                          // + span: $DIR/inline_cycle.rs:49:5: 49:9
++                                          // + span: $DIR/inline_cycle.rs:49:10: 49:11
 +                                          // + literal: Const { ty: fn() {f}, val: Value(<ZST>) }
-+         StorageLive(_3);                 // scope 1 at $DIR/inline-cycle.rs:54:5: 54:8
-+         StorageLive(_4);                 // scope 1 at $DIR/inline-cycle.rs:54:5: 54:6
-+         _4 = move _2;                    // scope 1 at $DIR/inline-cycle.rs:54:5: 54:6
-+         StorageLive(_5);                 // scope 1 at $DIR/inline-cycle.rs:54:5: 54:8
-+         StorageLive(_6);                 // scope 3 at $DIR/inline-cycle.rs:59:5: 59:12
-+         _6 = call::<fn() {f}>(f) -> bb1; // scope 3 at $DIR/inline-cycle.rs:59:5: 59:12
++         StorageLive(_3);                 // scope 1 at $DIR/inline_cycle.rs:54:5: 54:8
++         StorageLive(_4);                 // scope 1 at $DIR/inline_cycle.rs:54:5: 54:6
++         _4 = move _2;                    // scope 1 at $DIR/inline_cycle.rs:54:5: 54:6
++         StorageLive(_5);                 // scope 1 at $DIR/inline_cycle.rs:54:5: 54:8
++         StorageLive(_6);                 // scope 3 at $DIR/inline_cycle.rs:59:5: 59:12
++         _6 = call::<fn() {f}>(f) -> bb1; // scope 3 at $DIR/inline_cycle.rs:59:5: 59:12
 +                                          // mir::Constant
-+                                          // + span: $DIR/inline-cycle.rs:59:5: 59:9
++                                          // + span: $DIR/inline_cycle.rs:59:5: 59:9
                                            // + literal: Const { ty: fn(fn() {f}) {call::<fn() {f}>}, val: Value(<ZST>) }
                                            // mir::Constant
--                                          // + span: $DIR/inline-cycle.rs:49:10: 49:11
-+                                          // + span: $DIR/inline-cycle.rs:59:10: 59:11
+-                                          // + span: $DIR/inline_cycle.rs:49:10: 49:11
++                                          // + span: $DIR/inline_cycle.rs:59:10: 59:11
                                            // + literal: Const { ty: fn() {f}, val: Value(<ZST>) }
       }
   
       bb1: {
-+         StorageDead(_6);                 // scope 3 at $DIR/inline-cycle.rs:59:12: 59:13
-+         StorageDead(_5);                 // scope 1 at $DIR/inline-cycle.rs:54:7: 54:8
-+         StorageDead(_4);                 // scope 1 at $DIR/inline-cycle.rs:54:7: 54:8
-+         StorageDead(_3);                 // scope 1 at $DIR/inline-cycle.rs:54:8: 54:9
-+         StorageDead(_2);                 // scope 0 at $DIR/inline-cycle.rs:+1:5: +1:12
-          StorageDead(_1);                 // scope 0 at $DIR/inline-cycle.rs:+1:12: +1:13
-          _0 = const ();                   // scope 0 at $DIR/inline-cycle.rs:+0:10: +2:2
-          return;                          // scope 0 at $DIR/inline-cycle.rs:+2:2: +2:2
++         StorageDead(_6);                 // scope 3 at $DIR/inline_cycle.rs:59:12: 59:13
++         StorageDead(_5);                 // scope 1 at $DIR/inline_cycle.rs:54:7: 54:8
++         StorageDead(_4);                 // scope 1 at $DIR/inline_cycle.rs:54:7: 54:8
++         StorageDead(_3);                 // scope 1 at $DIR/inline_cycle.rs:54:8: 54:9
++         StorageDead(_2);                 // scope 0 at $DIR/inline_cycle.rs:+1:5: +1:12
+          StorageDead(_1);                 // scope 0 at $DIR/inline_cycle.rs:+1:12: +1:13
+          _0 = const ();                   // scope 0 at $DIR/inline_cycle.rs:+0:10: +2:2
+          return;                          // scope 0 at $DIR/inline_cycle.rs:+2:2: +2:2
       }
   }
   
diff --git a/src/test/mir-opt/inline/inline_cycle_generic.main.Inline.diff b/src/test/mir-opt/inline/inline_cycle_generic.main.Inline.diff
index fc5d57ce8bf2..52debab4dd1c 100644
--- a/src/test/mir-opt/inline/inline_cycle_generic.main.Inline.diff
+++ b/src/test/mir-opt/inline/inline_cycle_generic.main.Inline.diff
@@ -2,31 +2,31 @@
 + // MIR for `main` after Inline
   
   fn main() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/inline-cycle-generic.rs:+0:11: +0:11
-      let _1: ();                          // in scope 0 at $DIR/inline-cycle-generic.rs:+1:5: +1:24
-+     scope 1 (inlined <C as Call>::call) { // at $DIR/inline-cycle-generic.rs:9:5: 9:24
-+         scope 2 (inlined <B<A> as Call>::call) { // at $DIR/inline-cycle-generic.rs:38:9: 38:31
-+             scope 3 (inlined <A as Call>::call) { // at $DIR/inline-cycle-generic.rs:31:9: 31:28
-+                 scope 4 (inlined <B<C> as Call>::call) { // at $DIR/inline-cycle-generic.rs:23:9: 23:31
+      let mut _0: ();                      // return place in scope 0 at $DIR/inline_cycle_generic.rs:+0:11: +0:11
+      let _1: ();                          // in scope 0 at $DIR/inline_cycle_generic.rs:+1:5: +1:24
++     scope 1 (inlined <C as Call>::call) { // at $DIR/inline_cycle_generic.rs:9:5: 9:24
++         scope 2 (inlined <B<A> as Call>::call) { // at $DIR/inline_cycle_generic.rs:38:9: 38:31
++             scope 3 (inlined <A as Call>::call) { // at $DIR/inline_cycle_generic.rs:31:9: 31:28
++                 scope 4 (inlined <B<C> as Call>::call) { // at $DIR/inline_cycle_generic.rs:23:9: 23:31
 +                 }
 +             }
 +         }
 +     }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/inline-cycle-generic.rs:+1:5: +1:24
--         _1 = <C as Call>::call() -> bb1; // scope 0 at $DIR/inline-cycle-generic.rs:+1:5: +1:24
-+         _1 = <C as Call>::call() -> bb1; // scope 4 at $DIR/inline-cycle-generic.rs:31:9: 31:28
+          StorageLive(_1);                 // scope 0 at $DIR/inline_cycle_generic.rs:+1:5: +1:24
+-         _1 = <C as Call>::call() -> bb1; // scope 0 at $DIR/inline_cycle_generic.rs:+1:5: +1:24
++         _1 = <C as Call>::call() -> bb1; // scope 4 at $DIR/inline_cycle_generic.rs:31:9: 31:28
                                            // mir::Constant
--                                          // + span: $DIR/inline-cycle-generic.rs:9:5: 9:22
-+                                          // + span: $DIR/inline-cycle-generic.rs:31:9: 31:26
+-                                          // + span: $DIR/inline_cycle_generic.rs:9:5: 9:22
++                                          // + span: $DIR/inline_cycle_generic.rs:31:9: 31:26
                                            // + literal: Const { ty: fn() {<C as Call>::call}, val: Value(<ZST>) }
       }
   
       bb1: {
-          StorageDead(_1);                 // scope 0 at $DIR/inline-cycle-generic.rs:+1:24: +1:25
-          _0 = const ();                   // scope 0 at $DIR/inline-cycle-generic.rs:+0:11: +2:2
-          return;                          // scope 0 at $DIR/inline-cycle-generic.rs:+2:2: +2:2
+          StorageDead(_1);                 // scope 0 at $DIR/inline_cycle_generic.rs:+1:24: +1:25
+          _0 = const ();                   // scope 0 at $DIR/inline_cycle_generic.rs:+0:11: +2:2
+          return;                          // scope 0 at $DIR/inline_cycle_generic.rs:+2:2: +2:2
       }
   }
   
diff --git a/src/test/mir-opt/inline/inline-cycle-generic.rs b/src/test/mir-opt/inline/inline_cycle_generic.rs
similarity index 100%
rename from src/test/mir-opt/inline/inline-cycle-generic.rs
rename to src/test/mir-opt/inline/inline_cycle_generic.rs
diff --git a/src/test/mir-opt/inline/inline_diverging.f.Inline.diff b/src/test/mir-opt/inline/inline_diverging.f.Inline.diff
index cef4cfc67ab2..b49191f495b9 100644
--- a/src/test/mir-opt/inline/inline_diverging.f.Inline.diff
+++ b/src/test/mir-opt/inline/inline_diverging.f.Inline.diff
@@ -2,23 +2,23 @@
 + // MIR for `f` after Inline
   
   fn f() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/inline-diverging.rs:+0:12: +0:12
-      let mut _1: !;                       // in scope 0 at $DIR/inline-diverging.rs:+0:12: +2:2
-      let _2: !;                           // in scope 0 at $DIR/inline-diverging.rs:+1:5: +1:12
-+     scope 1 (inlined sleep) {            // at $DIR/inline-diverging.rs:8:5: 8:12
+      let mut _0: ();                      // return place in scope 0 at $DIR/inline_diverging.rs:+0:12: +0:12
+      let mut _1: !;                       // in scope 0 at $DIR/inline_diverging.rs:+0:12: +2:2
+      let _2: !;                           // in scope 0 at $DIR/inline_diverging.rs:+1:5: +1:12
++     scope 1 (inlined sleep) {            // at $DIR/inline_diverging.rs:8:5: 8:12
 +     }
   
       bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/inline-diverging.rs:+1:5: +1:12
--         _2 = sleep();                    // scope 0 at $DIR/inline-diverging.rs:+1:5: +1:12
+          StorageLive(_2);                 // scope 0 at $DIR/inline_diverging.rs:+1:5: +1:12
+-         _2 = sleep();                    // scope 0 at $DIR/inline_diverging.rs:+1:5: +1:12
 -                                          // mir::Constant
--                                          // + span: $DIR/inline-diverging.rs:8:5: 8:10
+-                                          // + span: $DIR/inline_diverging.rs:8:5: 8:10
 -                                          // + literal: Const { ty: fn() -> ! {sleep}, val: Value(<ZST>) }
-+         goto -> bb1;                     // scope 0 at $DIR/inline-diverging.rs:+1:5: +1:12
++         goto -> bb1;                     // scope 0 at $DIR/inline_diverging.rs:+1:5: +1:12
 +     }
 + 
 +     bb1: {
-+         goto -> bb1;                     // scope 1 at $DIR/inline-diverging.rs:39:5: 39:12
++         goto -> bb1;                     // scope 1 at $DIR/inline_diverging.rs:39:5: 39:12
       }
   }
   
diff --git a/src/test/mir-opt/inline/inline_diverging.g.Inline.diff b/src/test/mir-opt/inline/inline_diverging.g.Inline.diff
index a71baad3e3ed..1e703a8fd2ba 100644
--- a/src/test/mir-opt/inline/inline_diverging.g.Inline.diff
+++ b/src/test/mir-opt/inline/inline_diverging.g.Inline.diff
@@ -2,42 +2,42 @@
 + // MIR for `g` after Inline
   
   fn g(_1: i32) -> u32 {
-      debug i => _1;                       // in scope 0 at $DIR/inline-diverging.rs:+0:10: +0:11
-      let mut _0: u32;                     // return place in scope 0 at $DIR/inline-diverging.rs:+0:21: +0:24
-      let mut _2: bool;                    // in scope 0 at $DIR/inline-diverging.rs:+1:8: +1:13
-      let mut _3: i32;                     // in scope 0 at $DIR/inline-diverging.rs:+1:8: +1:9
-      let mut _4: i32;                     // in scope 0 at $DIR/inline-diverging.rs:+2:9: +2:10
-      let mut _5: !;                       // in scope 0 at $DIR/inline-diverging.rs:+3:12: +5:6
-      let _6: !;                           // in scope 0 at $DIR/inline-diverging.rs:+4:9: +4:16
-+     scope 1 (inlined panic) {            // at $DIR/inline-diverging.rs:16:9: 16:16
+      debug i => _1;                       // in scope 0 at $DIR/inline_diverging.rs:+0:10: +0:11
+      let mut _0: u32;                     // return place in scope 0 at $DIR/inline_diverging.rs:+0:21: +0:24
+      let mut _2: bool;                    // in scope 0 at $DIR/inline_diverging.rs:+1:8: +1:13
+      let mut _3: i32;                     // in scope 0 at $DIR/inline_diverging.rs:+1:8: +1:9
+      let mut _4: i32;                     // in scope 0 at $DIR/inline_diverging.rs:+2:9: +2:10
+      let mut _5: !;                       // in scope 0 at $DIR/inline_diverging.rs:+3:12: +5:6
+      let _6: !;                           // in scope 0 at $DIR/inline_diverging.rs:+4:9: +4:16
++     scope 1 (inlined panic) {            // at $DIR/inline_diverging.rs:16:9: 16:16
 +         let mut _7: !;                   // in scope 1 at $SRC_DIR/std/src/panic.rs:LL:COL
 +     }
   
       bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/inline-diverging.rs:+1:8: +1:13
-          StorageLive(_3);                 // scope 0 at $DIR/inline-diverging.rs:+1:8: +1:9
-          _3 = _1;                         // scope 0 at $DIR/inline-diverging.rs:+1:8: +1:9
-          _2 = Gt(move _3, const 0_i32);   // scope 0 at $DIR/inline-diverging.rs:+1:8: +1:13
-          StorageDead(_3);                 // scope 0 at $DIR/inline-diverging.rs:+1:12: +1:13
-          switchInt(move _2) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/inline-diverging.rs:+1:8: +1:13
+          StorageLive(_2);                 // scope 0 at $DIR/inline_diverging.rs:+1:8: +1:13
+          StorageLive(_3);                 // scope 0 at $DIR/inline_diverging.rs:+1:8: +1:9
+          _3 = _1;                         // scope 0 at $DIR/inline_diverging.rs:+1:8: +1:9
+          _2 = Gt(move _3, const 0_i32);   // scope 0 at $DIR/inline_diverging.rs:+1:8: +1:13
+          StorageDead(_3);                 // scope 0 at $DIR/inline_diverging.rs:+1:12: +1:13
+          switchInt(move _2) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/inline_diverging.rs:+1:8: +1:13
       }
   
       bb1: {
-          StorageLive(_4);                 // scope 0 at $DIR/inline-diverging.rs:+2:9: +2:10
-          _4 = _1;                         // scope 0 at $DIR/inline-diverging.rs:+2:9: +2:10
-          _0 = move _4 as u32 (IntToInt);  // scope 0 at $DIR/inline-diverging.rs:+2:9: +2:17
-          StorageDead(_4);                 // scope 0 at $DIR/inline-diverging.rs:+2:16: +2:17
-          StorageDead(_2);                 // scope 0 at $DIR/inline-diverging.rs:+5:5: +5:6
-          return;                          // scope 0 at $DIR/inline-diverging.rs:+6:2: +6:2
+          StorageLive(_4);                 // scope 0 at $DIR/inline_diverging.rs:+2:9: +2:10
+          _4 = _1;                         // scope 0 at $DIR/inline_diverging.rs:+2:9: +2:10
+          _0 = move _4 as u32 (IntToInt);  // scope 0 at $DIR/inline_diverging.rs:+2:9: +2:17
+          StorageDead(_4);                 // scope 0 at $DIR/inline_diverging.rs:+2:16: +2:17
+          StorageDead(_2);                 // scope 0 at $DIR/inline_diverging.rs:+5:5: +5:6
+          return;                          // scope 0 at $DIR/inline_diverging.rs:+6:2: +6:2
       }
   
       bb2: {
-          StorageLive(_6);                 // scope 0 at $DIR/inline-diverging.rs:+4:9: +4:16
--         _6 = panic();                    // scope 0 at $DIR/inline-diverging.rs:+4:9: +4:16
+          StorageLive(_6);                 // scope 0 at $DIR/inline_diverging.rs:+4:9: +4:16
+-         _6 = panic();                    // scope 0 at $DIR/inline_diverging.rs:+4:9: +4:16
 +         StorageLive(_7);                 // scope 1 at $SRC_DIR/std/src/panic.rs:LL:COL
 +         _7 = begin_panic::<&str>(const "explicit panic"); // scope 1 at $SRC_DIR/std/src/panic.rs:LL:COL
                                            // mir::Constant
--                                          // + span: $DIR/inline-diverging.rs:16:9: 16:14
+-                                          // + span: $DIR/inline_diverging.rs:16:9: 16:14
 -                                          // + literal: Const { ty: fn() -> ! {panic}, val: Value(<ZST>) }
 +                                          // + span: $SRC_DIR/std/src/panic.rs:LL:COL
 +                                          // + literal: Const { ty: fn(&str) -> ! {begin_panic::<&str>}, val: Value(<ZST>) }
diff --git a/src/test/mir-opt/inline/inline_diverging.h.Inline.diff b/src/test/mir-opt/inline/inline_diverging.h.Inline.diff
index 6569ab24c381..152153a813ce 100644
--- a/src/test/mir-opt/inline/inline_diverging.h.Inline.diff
+++ b/src/test/mir-opt/inline/inline_diverging.h.Inline.diff
@@ -2,55 +2,55 @@
 + // MIR for `h` after Inline
   
   fn h() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/inline-diverging.rs:+0:12: +0:12
-      let _1: (!, !);                      // in scope 0 at $DIR/inline-diverging.rs:+1:5: +1:22
-+     let mut _2: fn() -> ! {sleep};       // in scope 0 at $DIR/inline-diverging.rs:+1:5: +1:22
-+     scope 1 (inlined call_twice::<!, fn() -> ! {sleep}>) { // at $DIR/inline-diverging.rs:22:5: 22:22
-+         debug f => _2;                   // in scope 1 at $DIR/inline-diverging.rs:26:36: 26:37
-+         let _3: !;                       // in scope 1 at $DIR/inline-diverging.rs:27:9: 27:10
-+         let mut _4: &fn() -> ! {sleep};  // in scope 1 at $DIR/inline-diverging.rs:27:13: 27:14
-+         let mut _5: ();                  // in scope 1 at $DIR/inline-diverging.rs:27:13: 27:16
-+         let mut _7: &fn() -> ! {sleep};  // in scope 1 at $DIR/inline-diverging.rs:28:13: 28:14
-+         let mut _8: ();                  // in scope 1 at $DIR/inline-diverging.rs:28:13: 28:16
-+         let mut _9: !;                   // in scope 1 at $DIR/inline-diverging.rs:29:6: 29:7
-+         let mut _10: !;                  // in scope 1 at $DIR/inline-diverging.rs:29:9: 29:10
+      let mut _0: ();                      // return place in scope 0 at $DIR/inline_diverging.rs:+0:12: +0:12
+      let _1: (!, !);                      // in scope 0 at $DIR/inline_diverging.rs:+1:5: +1:22
++     let mut _2: fn() -> ! {sleep};       // in scope 0 at $DIR/inline_diverging.rs:+1:5: +1:22
++     scope 1 (inlined call_twice::<!, fn() -> ! {sleep}>) { // at $DIR/inline_diverging.rs:22:5: 22:22
++         debug f => _2;                   // in scope 1 at $DIR/inline_diverging.rs:26:36: 26:37
++         let _3: !;                       // in scope 1 at $DIR/inline_diverging.rs:27:9: 27:10
++         let mut _4: &fn() -> ! {sleep};  // in scope 1 at $DIR/inline_diverging.rs:27:13: 27:14
++         let mut _5: ();                  // in scope 1 at $DIR/inline_diverging.rs:27:13: 27:16
++         let mut _7: &fn() -> ! {sleep};  // in scope 1 at $DIR/inline_diverging.rs:28:13: 28:14
++         let mut _8: ();                  // in scope 1 at $DIR/inline_diverging.rs:28:13: 28:16
++         let mut _9: !;                   // in scope 1 at $DIR/inline_diverging.rs:29:6: 29:7
++         let mut _10: !;                  // in scope 1 at $DIR/inline_diverging.rs:29:9: 29:10
 +         scope 2 {
-+             debug a => _3;               // in scope 2 at $DIR/inline-diverging.rs:27:9: 27:10
-+             let _6: !;                   // in scope 2 at $DIR/inline-diverging.rs:28:9: 28:10
++             debug a => _3;               // in scope 2 at $DIR/inline_diverging.rs:27:9: 27:10
++             let _6: !;                   // in scope 2 at $DIR/inline_diverging.rs:28:9: 28:10
 +             scope 3 {
-+                 debug b => _6;           // in scope 3 at $DIR/inline-diverging.rs:28:9: 28:10
++                 debug b => _6;           // in scope 3 at $DIR/inline_diverging.rs:28:9: 28:10
 +             }
-+             scope 6 (inlined <fn() -> ! {sleep} as Fn<()>>::call - shim(fn() -> ! {sleep})) { // at $DIR/inline-diverging.rs:28:13: 28:16
++             scope 6 (inlined <fn() -> ! {sleep} as Fn<()>>::call - shim(fn() -> ! {sleep})) { // at $DIR/inline_diverging.rs:28:13: 28:16
 +                 scope 7 (inlined sleep) { // at $SRC_DIR/core/src/ops/function.rs:LL:COL
 +                 }
 +             }
 +         }
-+         scope 4 (inlined <fn() -> ! {sleep} as Fn<()>>::call - shim(fn() -> ! {sleep})) { // at $DIR/inline-diverging.rs:27:13: 27:16
++         scope 4 (inlined <fn() -> ! {sleep} as Fn<()>>::call - shim(fn() -> ! {sleep})) { // at $DIR/inline_diverging.rs:27:13: 27:16
 +             scope 5 (inlined sleep) {    // at $SRC_DIR/core/src/ops/function.rs:LL:COL
 +             }
 +         }
 +     }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/inline-diverging.rs:+1:5: +1:22
--         _1 = call_twice::<!, fn() -> ! {sleep}>(sleep); // scope 0 at $DIR/inline-diverging.rs:+1:5: +1:22
-+         StorageLive(_2);                 // scope 0 at $DIR/inline-diverging.rs:+1:5: +1:22
-+         _2 = sleep;                      // scope 0 at $DIR/inline-diverging.rs:+1:5: +1:22
+          StorageLive(_1);                 // scope 0 at $DIR/inline_diverging.rs:+1:5: +1:22
+-         _1 = call_twice::<!, fn() -> ! {sleep}>(sleep); // scope 0 at $DIR/inline_diverging.rs:+1:5: +1:22
++         StorageLive(_2);                 // scope 0 at $DIR/inline_diverging.rs:+1:5: +1:22
++         _2 = sleep;                      // scope 0 at $DIR/inline_diverging.rs:+1:5: +1:22
                                            // mir::Constant
--                                          // + span: $DIR/inline-diverging.rs:22:5: 22:15
+-                                          // + span: $DIR/inline_diverging.rs:22:5: 22:15
 -                                          // + literal: Const { ty: fn(fn() -> ! {sleep}) -> (!, !) {call_twice::<!, fn() -> ! {sleep}>}, val: Value(<ZST>) }
 -                                          // mir::Constant
-                                           // + span: $DIR/inline-diverging.rs:22:16: 22:21
+                                           // + span: $DIR/inline_diverging.rs:22:16: 22:21
                                            // + literal: Const { ty: fn() -> ! {sleep}, val: Value(<ZST>) }
-+         StorageLive(_3);                 // scope 1 at $DIR/inline-diverging.rs:27:9: 27:10
-+         StorageLive(_4);                 // scope 1 at $DIR/inline-diverging.rs:27:13: 27:14
-+         _4 = &_2;                        // scope 1 at $DIR/inline-diverging.rs:27:13: 27:14
-+         StorageLive(_5);                 // scope 1 at $DIR/inline-diverging.rs:27:13: 27:16
-+         goto -> bb1;                     // scope 5 at $DIR/inline-diverging.rs:39:5: 39:12
++         StorageLive(_3);                 // scope 1 at $DIR/inline_diverging.rs:27:9: 27:10
++         StorageLive(_4);                 // scope 1 at $DIR/inline_diverging.rs:27:13: 27:14
++         _4 = &_2;                        // scope 1 at $DIR/inline_diverging.rs:27:13: 27:14
++         StorageLive(_5);                 // scope 1 at $DIR/inline_diverging.rs:27:13: 27:16
++         goto -> bb1;                     // scope 5 at $DIR/inline_diverging.rs:39:5: 39:12
 +     }
 + 
 +     bb1: {
-+         goto -> bb1;                     // scope 5 at $DIR/inline-diverging.rs:39:5: 39:12
++         goto -> bb1;                     // scope 5 at $DIR/inline_diverging.rs:39:5: 39:12
       }
   }
   
diff --git a/src/test/mir-opt/inline/inline-diverging.rs b/src/test/mir-opt/inline/inline_diverging.rs
similarity index 100%
rename from src/test/mir-opt/inline/inline-diverging.rs
rename to src/test/mir-opt/inline/inline_diverging.rs
diff --git a/src/test/mir-opt/inline/inline_generator.main.Inline.diff b/src/test/mir-opt/inline/inline_generator.main.Inline.diff
index 3fd8aad72388..26202f2f40db 100644
--- a/src/test/mir-opt/inline/inline_generator.main.Inline.diff
+++ b/src/test/mir-opt/inline/inline_generator.main.Inline.diff
@@ -2,59 +2,59 @@
 + // MIR for `main` after Inline
   
   fn main() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/inline-generator.rs:+0:11: +0:11
-      let _1: std::ops::GeneratorState<i32, bool>; // in scope 0 at $DIR/inline-generator.rs:+1:9: +1:11
-      let mut _2: std::pin::Pin<&mut [generator@$DIR/inline-generator.rs:15:5: 15:8]>; // in scope 0 at $DIR/inline-generator.rs:+1:14: +1:32
-      let mut _3: &mut [generator@$DIR/inline-generator.rs:15:5: 15:8]; // in scope 0 at $DIR/inline-generator.rs:+1:23: +1:31
-      let mut _4: [generator@$DIR/inline-generator.rs:15:5: 15:8]; // in scope 0 at $DIR/inline-generator.rs:+1:28: +1:31
-+     let mut _7: bool;                    // in scope 0 at $DIR/inline-generator.rs:+1:14: +1:46
+      let mut _0: ();                      // return place in scope 0 at $DIR/inline_generator.rs:+0:11: +0:11
+      let _1: std::ops::GeneratorState<i32, bool>; // in scope 0 at $DIR/inline_generator.rs:+1:9: +1:11
+      let mut _2: std::pin::Pin<&mut [generator@$DIR/inline_generator.rs:15:5: 15:8]>; // in scope 0 at $DIR/inline_generator.rs:+1:14: +1:32
+      let mut _3: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]; // in scope 0 at $DIR/inline_generator.rs:+1:23: +1:31
+      let mut _4: [generator@$DIR/inline_generator.rs:15:5: 15:8]; // in scope 0 at $DIR/inline_generator.rs:+1:28: +1:31
++     let mut _7: bool;                    // in scope 0 at $DIR/inline_generator.rs:+1:14: +1:46
       scope 1 {
-          debug _r => _1;                  // in scope 1 at $DIR/inline-generator.rs:+1:9: +1:11
+          debug _r => _1;                  // in scope 1 at $DIR/inline_generator.rs:+1:9: +1:11
       }
-+     scope 2 (inlined g) {                // at $DIR/inline-generator.rs:9:28: 9:31
++     scope 2 (inlined g) {                // at $DIR/inline_generator.rs:9:28: 9:31
 +     }
-+     scope 3 (inlined Pin::<&mut [generator@$DIR/inline-generator.rs:15:5: 15:8]>::new) { // at $DIR/inline-generator.rs:9:14: 9:32
++     scope 3 (inlined Pin::<&mut [generator@$DIR/inline_generator.rs:15:5: 15:8]>::new) { // at $DIR/inline_generator.rs:9:14: 9:32
 +         debug pointer => _3;             // in scope 3 at $SRC_DIR/core/src/pin.rs:LL:COL
-+         let mut _5: &mut [generator@$DIR/inline-generator.rs:15:5: 15:8]; // in scope 3 at $SRC_DIR/core/src/pin.rs:LL:COL
++         let mut _5: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]; // in scope 3 at $SRC_DIR/core/src/pin.rs:LL:COL
 +         scope 4 {
-+             scope 5 (inlined Pin::<&mut [generator@$DIR/inline-generator.rs:15:5: 15:8]>::new_unchecked) { // at $SRC_DIR/core/src/pin.rs:LL:COL
++             scope 5 (inlined Pin::<&mut [generator@$DIR/inline_generator.rs:15:5: 15:8]>::new_unchecked) { // at $SRC_DIR/core/src/pin.rs:LL:COL
 +                 debug pointer => _5;     // in scope 5 at $SRC_DIR/core/src/pin.rs:LL:COL
-+                 let mut _6: &mut [generator@$DIR/inline-generator.rs:15:5: 15:8]; // in scope 5 at $SRC_DIR/core/src/pin.rs:LL:COL
++                 let mut _6: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]; // in scope 5 at $SRC_DIR/core/src/pin.rs:LL:COL
 +             }
 +         }
 +     }
-+     scope 6 (inlined g::{closure#0}) {   // at $DIR/inline-generator.rs:9:14: 9:46
-+         debug a => _11;                  // in scope 6 at $DIR/inline-generator.rs:15:6: 15:7
-+         let mut _8: i32;                 // in scope 6 at $DIR/inline-generator.rs:15:17: 15:39
-+         let mut _9: bool;                // in scope 6 at $DIR/inline-generator.rs:15:20: 15:21
-+         let mut _10: bool;               // in scope 6 at $DIR/inline-generator.rs:15:9: 15:9
-+         let _11: bool;                   // in scope 6 at $DIR/inline-generator.rs:15:6: 15:7
-+         let mut _12: u32;                // in scope 6 at $DIR/inline-generator.rs:15:5: 15:41
-+         let mut _13: &mut [generator@$DIR/inline-generator.rs:15:5: 15:8]; // in scope 6 at $DIR/inline-generator.rs:15:5: 15:41
-+         let mut _14: &mut [generator@$DIR/inline-generator.rs:15:5: 15:8]; // in scope 6 at $DIR/inline-generator.rs:15:5: 15:41
-+         let mut _15: &mut [generator@$DIR/inline-generator.rs:15:5: 15:8]; // in scope 6 at $DIR/inline-generator.rs:15:5: 15:41
++     scope 6 (inlined g::{closure#0}) {   // at $DIR/inline_generator.rs:9:14: 9:46
++         debug a => _11;                  // in scope 6 at $DIR/inline_generator.rs:15:6: 15:7
++         let mut _8: i32;                 // in scope 6 at $DIR/inline_generator.rs:15:17: 15:39
++         let mut _9: bool;                // in scope 6 at $DIR/inline_generator.rs:15:20: 15:21
++         let mut _10: bool;               // in scope 6 at $DIR/inline_generator.rs:15:9: 15:9
++         let _11: bool;                   // in scope 6 at $DIR/inline_generator.rs:15:6: 15:7
++         let mut _12: u32;                // in scope 6 at $DIR/inline_generator.rs:15:5: 15:41
++         let mut _13: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]; // in scope 6 at $DIR/inline_generator.rs:15:5: 15:41
++         let mut _14: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]; // in scope 6 at $DIR/inline_generator.rs:15:5: 15:41
++         let mut _15: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]; // in scope 6 at $DIR/inline_generator.rs:15:5: 15:41
 +     }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/inline-generator.rs:+1:9: +1:11
-          StorageLive(_2);                 // scope 0 at $DIR/inline-generator.rs:+1:14: +1:32
-          StorageLive(_3);                 // scope 0 at $DIR/inline-generator.rs:+1:23: +1:31
-          StorageLive(_4);                 // scope 0 at $DIR/inline-generator.rs:+1:28: +1:31
--         _4 = g() -> bb1;                 // scope 0 at $DIR/inline-generator.rs:+1:28: +1:31
+          StorageLive(_1);                 // scope 0 at $DIR/inline_generator.rs:+1:9: +1:11
+          StorageLive(_2);                 // scope 0 at $DIR/inline_generator.rs:+1:14: +1:32
+          StorageLive(_3);                 // scope 0 at $DIR/inline_generator.rs:+1:23: +1:31
+          StorageLive(_4);                 // scope 0 at $DIR/inline_generator.rs:+1:28: +1:31
+-         _4 = g() -> bb1;                 // scope 0 at $DIR/inline_generator.rs:+1:28: +1:31
 -                                          // mir::Constant
--                                          // + span: $DIR/inline-generator.rs:9:28: 9:29
+-                                          // + span: $DIR/inline_generator.rs:9:28: 9:29
 -                                          // + literal: Const { ty: fn() -> impl Generator<bool> {g}, val: Value(<ZST>) }
 -     }
 - 
 -     bb1: {
-+         Deinit(_4);                      // scope 2 at $DIR/inline-generator.rs:15:5: 15:41
-+         discriminant(_4) = 0;            // scope 2 at $DIR/inline-generator.rs:15:5: 15:41
-          _3 = &mut _4;                    // scope 0 at $DIR/inline-generator.rs:+1:23: +1:31
--         _2 = Pin::<&mut [generator@$DIR/inline-generator.rs:15:5: 15:8]>::new(move _3) -> [return: bb2, unwind: bb4]; // scope 0 at $DIR/inline-generator.rs:+1:14: +1:32
++         Deinit(_4);                      // scope 2 at $DIR/inline_generator.rs:15:5: 15:41
++         discriminant(_4) = 0;            // scope 2 at $DIR/inline_generator.rs:15:5: 15:41
+          _3 = &mut _4;                    // scope 0 at $DIR/inline_generator.rs:+1:23: +1:31
+-         _2 = Pin::<&mut [generator@$DIR/inline_generator.rs:15:5: 15:8]>::new(move _3) -> [return: bb2, unwind: bb4]; // scope 0 at $DIR/inline_generator.rs:+1:14: +1:32
 -                                          // mir::Constant
--                                          // + span: $DIR/inline-generator.rs:9:14: 9:22
+-                                          // + span: $DIR/inline_generator.rs:9:14: 9:22
 -                                          // + user_ty: UserType(0)
--                                          // + literal: Const { ty: fn(&mut [generator@$DIR/inline-generator.rs:15:5: 15:8]) -> Pin<&mut [generator@$DIR/inline-generator.rs:15:5: 15:8]> {Pin::<&mut [generator@$DIR/inline-generator.rs:15:5: 15:8]>::new}, val: Value(<ZST>) }
+-                                          // + literal: Const { ty: fn(&mut [generator@$DIR/inline_generator.rs:15:5: 15:8]) -> Pin<&mut [generator@$DIR/inline_generator.rs:15:5: 15:8]> {Pin::<&mut [generator@$DIR/inline_generator.rs:15:5: 15:8]>::new}, val: Value(<ZST>) }
 -     }
 - 
 -     bb2: {
@@ -63,86 +63,86 @@
 +         StorageLive(_6);                 // scope 5 at $SRC_DIR/core/src/pin.rs:LL:COL
 +         _6 = move _5;                    // scope 5 at $SRC_DIR/core/src/pin.rs:LL:COL
 +         Deinit(_2);                      // scope 5 at $SRC_DIR/core/src/pin.rs:LL:COL
-+         (_2.0: &mut [generator@$DIR/inline-generator.rs:15:5: 15:8]) = move _6; // scope 5 at $SRC_DIR/core/src/pin.rs:LL:COL
++         (_2.0: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]) = move _6; // scope 5 at $SRC_DIR/core/src/pin.rs:LL:COL
 +         StorageDead(_6);                 // scope 5 at $SRC_DIR/core/src/pin.rs:LL:COL
 +         StorageDead(_5);                 // scope 4 at $SRC_DIR/core/src/pin.rs:LL:COL
-          StorageDead(_3);                 // scope 0 at $DIR/inline-generator.rs:+1:31: +1:32
--         _1 = <[generator@$DIR/inline-generator.rs:15:5: 15:8] as Generator<bool>>::resume(move _2, const false) -> [return: bb3, unwind: bb4]; // scope 0 at $DIR/inline-generator.rs:+1:14: +1:46
+          StorageDead(_3);                 // scope 0 at $DIR/inline_generator.rs:+1:31: +1:32
+-         _1 = <[generator@$DIR/inline_generator.rs:15:5: 15:8] as Generator<bool>>::resume(move _2, const false) -> [return: bb3, unwind: bb4]; // scope 0 at $DIR/inline_generator.rs:+1:14: +1:46
 -                                          // mir::Constant
--                                          // + span: $DIR/inline-generator.rs:9:33: 9:39
--                                          // + literal: Const { ty: for<'a> fn(Pin<&'a mut [generator@$DIR/inline-generator.rs:15:5: 15:8]>, bool) -> GeneratorState<<[generator@$DIR/inline-generator.rs:15:5: 15:8] as Generator<bool>>::Yield, <[generator@$DIR/inline-generator.rs:15:5: 15:8] as Generator<bool>>::Return> {<[generator@$DIR/inline-generator.rs:15:5: 15:8] as Generator<bool>>::resume}, val: Value(<ZST>) }
-+         StorageLive(_7);                 // scope 0 at $DIR/inline-generator.rs:+1:14: +1:46
-+         _7 = const false;                // scope 0 at $DIR/inline-generator.rs:+1:14: +1:46
-+         StorageLive(_10);                // scope 0 at $DIR/inline-generator.rs:+1:14: +1:46
-+         StorageLive(_11);                // scope 0 at $DIR/inline-generator.rs:+1:14: +1:46
-+         _13 = deref_copy (_2.0: &mut [generator@$DIR/inline-generator.rs:15:5: 15:8]); // scope 6 at $DIR/inline-generator.rs:15:5: 15:41
-+         _12 = discriminant((*_13));      // scope 6 at $DIR/inline-generator.rs:15:5: 15:41
-+         switchInt(move _12) -> [0_u32: bb3, 1_u32: bb8, 3_u32: bb7, otherwise: bb9]; // scope 6 at $DIR/inline-generator.rs:15:5: 15:41
+-                                          // + span: $DIR/inline_generator.rs:9:33: 9:39
+-                                          // + literal: Const { ty: for<'a> fn(Pin<&'a mut [generator@$DIR/inline_generator.rs:15:5: 15:8]>, bool) -> GeneratorState<<[generator@$DIR/inline_generator.rs:15:5: 15:8] as Generator<bool>>::Yield, <[generator@$DIR/inline_generator.rs:15:5: 15:8] as Generator<bool>>::Return> {<[generator@$DIR/inline_generator.rs:15:5: 15:8] as Generator<bool>>::resume}, val: Value(<ZST>) }
++         StorageLive(_7);                 // scope 0 at $DIR/inline_generator.rs:+1:14: +1:46
++         _7 = const false;                // scope 0 at $DIR/inline_generator.rs:+1:14: +1:46
++         StorageLive(_10);                // scope 0 at $DIR/inline_generator.rs:+1:14: +1:46
++         StorageLive(_11);                // scope 0 at $DIR/inline_generator.rs:+1:14: +1:46
++         _13 = deref_copy (_2.0: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]); // scope 6 at $DIR/inline_generator.rs:15:5: 15:41
++         _12 = discriminant((*_13));      // scope 6 at $DIR/inline_generator.rs:15:5: 15:41
++         switchInt(move _12) -> [0_u32: bb3, 1_u32: bb8, 3_u32: bb7, otherwise: bb9]; // scope 6 at $DIR/inline_generator.rs:15:5: 15:41
       }
   
 -     bb3: {
 +     bb1: {
-+         StorageDead(_11);                // scope 0 at $DIR/inline-generator.rs:+1:14: +1:46
-+         StorageDead(_10);                // scope 0 at $DIR/inline-generator.rs:+1:14: +1:46
-+         StorageDead(_7);                 // scope 0 at $DIR/inline-generator.rs:+1:14: +1:46
-          StorageDead(_2);                 // scope 0 at $DIR/inline-generator.rs:+1:45: +1:46
-          StorageDead(_4);                 // scope 0 at $DIR/inline-generator.rs:+1:46: +1:47
-          _0 = const ();                   // scope 0 at $DIR/inline-generator.rs:+0:11: +2:2
-          StorageDead(_1);                 // scope 0 at $DIR/inline-generator.rs:+2:1: +2:2
-          return;                          // scope 0 at $DIR/inline-generator.rs:+2:2: +2:2
++         StorageDead(_11);                // scope 0 at $DIR/inline_generator.rs:+1:14: +1:46
++         StorageDead(_10);                // scope 0 at $DIR/inline_generator.rs:+1:14: +1:46
++         StorageDead(_7);                 // scope 0 at $DIR/inline_generator.rs:+1:14: +1:46
+          StorageDead(_2);                 // scope 0 at $DIR/inline_generator.rs:+1:45: +1:46
+          StorageDead(_4);                 // scope 0 at $DIR/inline_generator.rs:+1:46: +1:47
+          _0 = const ();                   // scope 0 at $DIR/inline_generator.rs:+0:11: +2:2
+          StorageDead(_1);                 // scope 0 at $DIR/inline_generator.rs:+2:1: +2:2
+          return;                          // scope 0 at $DIR/inline_generator.rs:+2:2: +2:2
       }
   
 -     bb4 (cleanup): {
 +     bb2 (cleanup): {
-          resume;                          // scope 0 at $DIR/inline-generator.rs:+0:1: +2:2
+          resume;                          // scope 0 at $DIR/inline_generator.rs:+0:1: +2:2
 +     }
 + 
 +     bb3: {
-+         _11 = move _7;                   // scope 6 at $DIR/inline-generator.rs:15:5: 15:41
-+         StorageLive(_8);                 // scope 6 at $DIR/inline-generator.rs:15:17: 15:39
-+         StorageLive(_9);                 // scope 6 at $DIR/inline-generator.rs:15:20: 15:21
-+         _9 = _11;                        // scope 6 at $DIR/inline-generator.rs:15:20: 15:21
-+         switchInt(move _9) -> [false: bb5, otherwise: bb4]; // scope 6 at $DIR/inline-generator.rs:15:20: 15:21
++         _11 = move _7;                   // scope 6 at $DIR/inline_generator.rs:15:5: 15:41
++         StorageLive(_8);                 // scope 6 at $DIR/inline_generator.rs:15:17: 15:39
++         StorageLive(_9);                 // scope 6 at $DIR/inline_generator.rs:15:20: 15:21
++         _9 = _11;                        // scope 6 at $DIR/inline_generator.rs:15:20: 15:21
++         switchInt(move _9) -> [false: bb5, otherwise: bb4]; // scope 6 at $DIR/inline_generator.rs:15:20: 15:21
 +     }
 + 
 +     bb4: {
-+         _8 = const 7_i32;                // scope 6 at $DIR/inline-generator.rs:15:24: 15:25
-+         goto -> bb6;                     // scope 6 at $DIR/inline-generator.rs:15:17: 15:39
++         _8 = const 7_i32;                // scope 6 at $DIR/inline_generator.rs:15:24: 15:25
++         goto -> bb6;                     // scope 6 at $DIR/inline_generator.rs:15:17: 15:39
 +     }
 + 
 +     bb5: {
-+         _8 = const 13_i32;               // scope 6 at $DIR/inline-generator.rs:15:35: 15:37
-+         goto -> bb6;                     // scope 6 at $DIR/inline-generator.rs:15:17: 15:39
++         _8 = const 13_i32;               // scope 6 at $DIR/inline_generator.rs:15:35: 15:37
++         goto -> bb6;                     // scope 6 at $DIR/inline_generator.rs:15:17: 15:39
 +     }
 + 
 +     bb6: {
-+         StorageDead(_9);                 // scope 6 at $DIR/inline-generator.rs:15:38: 15:39
-+         Deinit(_1);                      // scope 6 at $DIR/inline-generator.rs:15:11: 15:39
-+         ((_1 as Yielded).0: i32) = move _8; // scope 6 at $DIR/inline-generator.rs:15:11: 15:39
-+         discriminant(_1) = 0;            // scope 6 at $DIR/inline-generator.rs:15:11: 15:39
-+         _14 = deref_copy (_2.0: &mut [generator@$DIR/inline-generator.rs:15:5: 15:8]); // scope 6 at $DIR/inline-generator.rs:15:11: 15:39
-+         discriminant((*_14)) = 3;        // scope 6 at $DIR/inline-generator.rs:15:11: 15:39
-+         goto -> bb1;                     // scope 0 at $DIR/inline-generator.rs:15:11: 15:39
++         StorageDead(_9);                 // scope 6 at $DIR/inline_generator.rs:15:38: 15:39
++         Deinit(_1);                      // scope 6 at $DIR/inline_generator.rs:15:11: 15:39
++         ((_1 as Yielded).0: i32) = move _8; // scope 6 at $DIR/inline_generator.rs:15:11: 15:39
++         discriminant(_1) = 0;            // scope 6 at $DIR/inline_generator.rs:15:11: 15:39
++         _14 = deref_copy (_2.0: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]); // scope 6 at $DIR/inline_generator.rs:15:11: 15:39
++         discriminant((*_14)) = 3;        // scope 6 at $DIR/inline_generator.rs:15:11: 15:39
++         goto -> bb1;                     // scope 0 at $DIR/inline_generator.rs:15:11: 15:39
 +     }
 + 
 +     bb7: {
-+         StorageLive(_8);                 // scope 6 at $DIR/inline-generator.rs:15:5: 15:41
-+         _10 = move _7;                   // scope 6 at $DIR/inline-generator.rs:15:5: 15:41
-+         StorageDead(_8);                 // scope 6 at $DIR/inline-generator.rs:15:38: 15:39
-+         Deinit(_1);                      // scope 6 at $DIR/inline-generator.rs:15:41: 15:41
-+         ((_1 as Complete).0: bool) = move _10; // scope 6 at $DIR/inline-generator.rs:15:41: 15:41
-+         discriminant(_1) = 1;            // scope 6 at $DIR/inline-generator.rs:15:41: 15:41
-+         _15 = deref_copy (_2.0: &mut [generator@$DIR/inline-generator.rs:15:5: 15:8]); // scope 6 at $DIR/inline-generator.rs:15:41: 15:41
-+         discriminant((*_15)) = 1;        // scope 6 at $DIR/inline-generator.rs:15:41: 15:41
-+         goto -> bb1;                     // scope 0 at $DIR/inline-generator.rs:15:41: 15:41
++         StorageLive(_8);                 // scope 6 at $DIR/inline_generator.rs:15:5: 15:41
++         _10 = move _7;                   // scope 6 at $DIR/inline_generator.rs:15:5: 15:41
++         StorageDead(_8);                 // scope 6 at $DIR/inline_generator.rs:15:38: 15:39
++         Deinit(_1);                      // scope 6 at $DIR/inline_generator.rs:15:41: 15:41
++         ((_1 as Complete).0: bool) = move _10; // scope 6 at $DIR/inline_generator.rs:15:41: 15:41
++         discriminant(_1) = 1;            // scope 6 at $DIR/inline_generator.rs:15:41: 15:41
++         _15 = deref_copy (_2.0: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]); // scope 6 at $DIR/inline_generator.rs:15:41: 15:41
++         discriminant((*_15)) = 1;        // scope 6 at $DIR/inline_generator.rs:15:41: 15:41
++         goto -> bb1;                     // scope 0 at $DIR/inline_generator.rs:15:41: 15:41
 +     }
 + 
 +     bb8: {
-+         assert(const false, "generator resumed after completion") -> [success: bb8, unwind: bb2]; // scope 6 at $DIR/inline-generator.rs:15:5: 15:41
++         assert(const false, "generator resumed after completion") -> [success: bb8, unwind: bb2]; // scope 6 at $DIR/inline_generator.rs:15:5: 15:41
 +     }
 + 
 +     bb9: {
-+         unreachable;                     // scope 6 at $DIR/inline-generator.rs:15:5: 15:41
++         unreachable;                     // scope 6 at $DIR/inline_generator.rs:15:5: 15:41
       }
   }
   
diff --git a/src/test/mir-opt/inline/inline-generator.rs b/src/test/mir-opt/inline/inline_generator.rs
similarity index 100%
rename from src/test/mir-opt/inline/inline-generator.rs
rename to src/test/mir-opt/inline/inline_generator.rs
diff --git a/src/test/mir-opt/inline/inline_instruction_set.default.Inline.diff b/src/test/mir-opt/inline/inline_instruction_set.default.Inline.diff
index 076509df3494..e421428dcdff 100644
--- a/src/test/mir-opt/inline/inline_instruction_set.default.Inline.diff
+++ b/src/test/mir-opt/inline/inline_instruction_set.default.Inline.diff
@@ -2,43 +2,43 @@
 + // MIR for `default` after Inline
   
   fn default() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/inline-instruction-set.rs:+0:18: +0:18
-      let _1: ();                          // in scope 0 at $DIR/inline-instruction-set.rs:+1:5: +1:26
-      let _2: ();                          // in scope 0 at $DIR/inline-instruction-set.rs:+2:5: +2:26
-      let _3: ();                          // in scope 0 at $DIR/inline-instruction-set.rs:+3:5: +3:30
-+     scope 1 (inlined instruction_set_default) { // at $DIR/inline-instruction-set.rs:53:5: 53:30
+      let mut _0: ();                      // return place in scope 0 at $DIR/inline_instruction_set.rs:+0:18: +0:18
+      let _1: ();                          // in scope 0 at $DIR/inline_instruction_set.rs:+1:5: +1:26
+      let _2: ();                          // in scope 0 at $DIR/inline_instruction_set.rs:+2:5: +2:26
+      let _3: ();                          // in scope 0 at $DIR/inline_instruction_set.rs:+3:5: +3:30
++     scope 1 (inlined instruction_set_default) { // at $DIR/inline_instruction_set.rs:53:5: 53:30
 +     }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/inline-instruction-set.rs:+1:5: +1:26
-          _1 = instruction_set_a32() -> bb1; // scope 0 at $DIR/inline-instruction-set.rs:+1:5: +1:26
+          StorageLive(_1);                 // scope 0 at $DIR/inline_instruction_set.rs:+1:5: +1:26
+          _1 = instruction_set_a32() -> bb1; // scope 0 at $DIR/inline_instruction_set.rs:+1:5: +1:26
                                            // mir::Constant
-                                           // + span: $DIR/inline-instruction-set.rs:51:5: 51:24
+                                           // + span: $DIR/inline_instruction_set.rs:51:5: 51:24
                                            // + literal: Const { ty: fn() {instruction_set_a32}, val: Value(<ZST>) }
       }
   
       bb1: {
-          StorageDead(_1);                 // scope 0 at $DIR/inline-instruction-set.rs:+1:26: +1:27
-          StorageLive(_2);                 // scope 0 at $DIR/inline-instruction-set.rs:+2:5: +2:26
-          _2 = instruction_set_t32() -> bb2; // scope 0 at $DIR/inline-instruction-set.rs:+2:5: +2:26
+          StorageDead(_1);                 // scope 0 at $DIR/inline_instruction_set.rs:+1:26: +1:27
+          StorageLive(_2);                 // scope 0 at $DIR/inline_instruction_set.rs:+2:5: +2:26
+          _2 = instruction_set_t32() -> bb2; // scope 0 at $DIR/inline_instruction_set.rs:+2:5: +2:26
                                            // mir::Constant
-                                           // + span: $DIR/inline-instruction-set.rs:52:5: 52:24
+                                           // + span: $DIR/inline_instruction_set.rs:52:5: 52:24
                                            // + literal: Const { ty: fn() {instruction_set_t32}, val: Value(<ZST>) }
       }
   
       bb2: {
-          StorageDead(_2);                 // scope 0 at $DIR/inline-instruction-set.rs:+2:26: +2:27
-          StorageLive(_3);                 // scope 0 at $DIR/inline-instruction-set.rs:+3:5: +3:30
--         _3 = instruction_set_default() -> bb3; // scope 0 at $DIR/inline-instruction-set.rs:+3:5: +3:30
+          StorageDead(_2);                 // scope 0 at $DIR/inline_instruction_set.rs:+2:26: +2:27
+          StorageLive(_3);                 // scope 0 at $DIR/inline_instruction_set.rs:+3:5: +3:30
+-         _3 = instruction_set_default() -> bb3; // scope 0 at $DIR/inline_instruction_set.rs:+3:5: +3:30
 -                                          // mir::Constant
--                                          // + span: $DIR/inline-instruction-set.rs:53:5: 53:28
+-                                          // + span: $DIR/inline_instruction_set.rs:53:5: 53:28
 -                                          // + literal: Const { ty: fn() {instruction_set_default}, val: Value(<ZST>) }
 -     }
 - 
 -     bb3: {
-          StorageDead(_3);                 // scope 0 at $DIR/inline-instruction-set.rs:+3:30: +3:31
-          _0 = const ();                   // scope 0 at $DIR/inline-instruction-set.rs:+0:18: +4:2
-          return;                          // scope 0 at $DIR/inline-instruction-set.rs:+4:2: +4:2
+          StorageDead(_3);                 // scope 0 at $DIR/inline_instruction_set.rs:+3:30: +3:31
+          _0 = const ();                   // scope 0 at $DIR/inline_instruction_set.rs:+0:18: +4:2
+          return;                          // scope 0 at $DIR/inline_instruction_set.rs:+4:2: +4:2
       }
   }
   
diff --git a/src/test/mir-opt/inline/inline-instruction-set.rs b/src/test/mir-opt/inline/inline_instruction_set.rs
similarity index 100%
rename from src/test/mir-opt/inline/inline-instruction-set.rs
rename to src/test/mir-opt/inline/inline_instruction_set.rs
diff --git a/src/test/mir-opt/inline/inline_instruction_set.t32.Inline.diff b/src/test/mir-opt/inline/inline_instruction_set.t32.Inline.diff
index b275d08e05f9..1ea2b87e53ac 100644
--- a/src/test/mir-opt/inline/inline_instruction_set.t32.Inline.diff
+++ b/src/test/mir-opt/inline/inline_instruction_set.t32.Inline.diff
@@ -2,45 +2,45 @@
 + // MIR for `t32` after Inline
   
   fn t32() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/inline-instruction-set.rs:+0:14: +0:14
-      let _1: ();                          // in scope 0 at $DIR/inline-instruction-set.rs:+1:5: +1:26
-      let _2: ();                          // in scope 0 at $DIR/inline-instruction-set.rs:+2:5: +2:26
-      let _3: ();                          // in scope 0 at $DIR/inline-instruction-set.rs:+5:5: +5:30
-+     scope 1 (inlined instruction_set_t32) { // at $DIR/inline-instruction-set.rs:43:5: 43:26
+      let mut _0: ();                      // return place in scope 0 at $DIR/inline_instruction_set.rs:+0:14: +0:14
+      let _1: ();                          // in scope 0 at $DIR/inline_instruction_set.rs:+1:5: +1:26
+      let _2: ();                          // in scope 0 at $DIR/inline_instruction_set.rs:+2:5: +2:26
+      let _3: ();                          // in scope 0 at $DIR/inline_instruction_set.rs:+5:5: +5:30
++     scope 1 (inlined instruction_set_t32) { // at $DIR/inline_instruction_set.rs:43:5: 43:26
 +     }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/inline-instruction-set.rs:+1:5: +1:26
-          _1 = instruction_set_a32() -> bb1; // scope 0 at $DIR/inline-instruction-set.rs:+1:5: +1:26
+          StorageLive(_1);                 // scope 0 at $DIR/inline_instruction_set.rs:+1:5: +1:26
+          _1 = instruction_set_a32() -> bb1; // scope 0 at $DIR/inline_instruction_set.rs:+1:5: +1:26
                                            // mir::Constant
-                                           // + span: $DIR/inline-instruction-set.rs:42:5: 42:24
+                                           // + span: $DIR/inline_instruction_set.rs:42:5: 42:24
                                            // + literal: Const { ty: fn() {instruction_set_a32}, val: Value(<ZST>) }
       }
   
       bb1: {
-          StorageDead(_1);                 // scope 0 at $DIR/inline-instruction-set.rs:+1:26: +1:27
-          StorageLive(_2);                 // scope 0 at $DIR/inline-instruction-set.rs:+2:5: +2:26
--         _2 = instruction_set_t32() -> bb2; // scope 0 at $DIR/inline-instruction-set.rs:+2:5: +2:26
+          StorageDead(_1);                 // scope 0 at $DIR/inline_instruction_set.rs:+1:26: +1:27
+          StorageLive(_2);                 // scope 0 at $DIR/inline_instruction_set.rs:+2:5: +2:26
+-         _2 = instruction_set_t32() -> bb2; // scope 0 at $DIR/inline_instruction_set.rs:+2:5: +2:26
 -                                          // mir::Constant
--                                          // + span: $DIR/inline-instruction-set.rs:43:5: 43:24
+-                                          // + span: $DIR/inline_instruction_set.rs:43:5: 43:24
 -                                          // + literal: Const { ty: fn() {instruction_set_t32}, val: Value(<ZST>) }
 -     }
 - 
 -     bb2: {
-          StorageDead(_2);                 // scope 0 at $DIR/inline-instruction-set.rs:+2:26: +2:27
-          StorageLive(_3);                 // scope 0 at $DIR/inline-instruction-set.rs:+5:5: +5:30
--         _3 = instruction_set_default() -> bb3; // scope 0 at $DIR/inline-instruction-set.rs:+5:5: +5:30
-+         _3 = instruction_set_default() -> bb2; // scope 0 at $DIR/inline-instruction-set.rs:+5:5: +5:30
+          StorageDead(_2);                 // scope 0 at $DIR/inline_instruction_set.rs:+2:26: +2:27
+          StorageLive(_3);                 // scope 0 at $DIR/inline_instruction_set.rs:+5:5: +5:30
+-         _3 = instruction_set_default() -> bb3; // scope 0 at $DIR/inline_instruction_set.rs:+5:5: +5:30
++         _3 = instruction_set_default() -> bb2; // scope 0 at $DIR/inline_instruction_set.rs:+5:5: +5:30
                                            // mir::Constant
-                                           // + span: $DIR/inline-instruction-set.rs:46:5: 46:28
+                                           // + span: $DIR/inline_instruction_set.rs:46:5: 46:28
                                            // + literal: Const { ty: fn() {instruction_set_default}, val: Value(<ZST>) }
       }
   
 -     bb3: {
 +     bb2: {
-          StorageDead(_3);                 // scope 0 at $DIR/inline-instruction-set.rs:+5:30: +5:31
-          _0 = const ();                   // scope 0 at $DIR/inline-instruction-set.rs:+0:14: +6:2
-          return;                          // scope 0 at $DIR/inline-instruction-set.rs:+6:2: +6:2
+          StorageDead(_3);                 // scope 0 at $DIR/inline_instruction_set.rs:+5:30: +5:31
+          _0 = const ();                   // scope 0 at $DIR/inline_instruction_set.rs:+0:14: +6:2
+          return;                          // scope 0 at $DIR/inline_instruction_set.rs:+6:2: +6:2
       }
   }
   
diff --git a/src/test/mir-opt/inline/inline_into_box_place.main.Inline.diff b/src/test/mir-opt/inline/inline_into_box_place.main.Inline.diff
index 7e017373b441..2a4dc9e3e809 100644
--- a/src/test/mir-opt/inline/inline_into_box_place.main.Inline.diff
+++ b/src/test/mir-opt/inline/inline_into_box_place.main.Inline.diff
@@ -2,45 +2,45 @@
 + // MIR for `main` after Inline
   
   fn main() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/inline-into-box-place.rs:+0:11: +0:11
-      let _1: std::boxed::Box<std::vec::Vec<u32>>; // in scope 0 at $DIR/inline-into-box-place.rs:+1:9: +1:11
-      let mut _2: usize;                   // in scope 0 at $DIR/inline-into-box-place.rs:+1:29: +1:43
-      let mut _3: usize;                   // in scope 0 at $DIR/inline-into-box-place.rs:+1:29: +1:43
-      let mut _4: *mut u8;                 // in scope 0 at $DIR/inline-into-box-place.rs:+1:29: +1:43
-      let mut _5: std::boxed::Box<std::vec::Vec<u32>>; // in scope 0 at $DIR/inline-into-box-place.rs:+1:29: +1:43
-      let mut _6: ();                      // in scope 0 at $DIR/inline-into-box-place.rs:+1:42: +1:43
-      let mut _7: *const std::vec::Vec<u32>; // in scope 0 at $DIR/inline-into-box-place.rs:+1:29: +1:43
-+     let mut _8: &mut std::vec::Vec<u32>; // in scope 0 at $DIR/inline-into-box-place.rs:+1:33: +1:43
+      let mut _0: ();                      // return place in scope 0 at $DIR/inline_into_box_place.rs:+0:11: +0:11
+      let _1: std::boxed::Box<std::vec::Vec<u32>>; // in scope 0 at $DIR/inline_into_box_place.rs:+1:9: +1:11
+      let mut _2: usize;                   // in scope 0 at $DIR/inline_into_box_place.rs:+1:29: +1:43
+      let mut _3: usize;                   // in scope 0 at $DIR/inline_into_box_place.rs:+1:29: +1:43
+      let mut _4: *mut u8;                 // in scope 0 at $DIR/inline_into_box_place.rs:+1:29: +1:43
+      let mut _5: std::boxed::Box<std::vec::Vec<u32>>; // in scope 0 at $DIR/inline_into_box_place.rs:+1:29: +1:43
+      let mut _6: ();                      // in scope 0 at $DIR/inline_into_box_place.rs:+1:42: +1:43
+      let mut _7: *const std::vec::Vec<u32>; // in scope 0 at $DIR/inline_into_box_place.rs:+1:29: +1:43
++     let mut _8: &mut std::vec::Vec<u32>; // in scope 0 at $DIR/inline_into_box_place.rs:+1:33: +1:43
       scope 1 {
-          debug _x => _1;                  // in scope 1 at $DIR/inline-into-box-place.rs:+1:9: +1:11
+          debug _x => _1;                  // in scope 1 at $DIR/inline_into_box_place.rs:+1:9: +1:11
       }
       scope 2 {
       }
-+     scope 3 (inlined Vec::<u32>::new) {  // at $DIR/inline-into-box-place.rs:8:33: 8:43
++     scope 3 (inlined Vec::<u32>::new) {  // at $DIR/inline_into_box_place.rs:8:33: 8:43
 +         let mut _9: alloc::raw_vec::RawVec<u32>; // in scope 3 at $SRC_DIR/alloc/src/vec/mod.rs:LL:COL
 +     }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/inline-into-box-place.rs:+1:9: +1:11
-          _2 = SizeOf(std::vec::Vec<u32>); // scope 2 at $DIR/inline-into-box-place.rs:+1:29: +1:43
-          _3 = AlignOf(std::vec::Vec<u32>); // scope 2 at $DIR/inline-into-box-place.rs:+1:29: +1:43
-          _4 = alloc::alloc::exchange_malloc(move _2, move _3) -> bb1; // scope 2 at $DIR/inline-into-box-place.rs:+1:29: +1:43
+          StorageLive(_1);                 // scope 0 at $DIR/inline_into_box_place.rs:+1:9: +1:11
+          _2 = SizeOf(std::vec::Vec<u32>); // scope 2 at $DIR/inline_into_box_place.rs:+1:29: +1:43
+          _3 = AlignOf(std::vec::Vec<u32>); // scope 2 at $DIR/inline_into_box_place.rs:+1:29: +1:43
+          _4 = alloc::alloc::exchange_malloc(move _2, move _3) -> bb1; // scope 2 at $DIR/inline_into_box_place.rs:+1:29: +1:43
                                            // mir::Constant
-                                           // + span: $DIR/inline-into-box-place.rs:8:29: 8:43
+                                           // + span: $DIR/inline_into_box_place.rs:8:29: 8:43
                                            // + literal: Const { ty: unsafe fn(usize, usize) -> *mut u8 {alloc::alloc::exchange_malloc}, val: Value(<ZST>) }
       }
   
       bb1: {
-          StorageLive(_5);                 // scope 0 at $DIR/inline-into-box-place.rs:+1:29: +1:43
-          _5 = ShallowInitBox(move _4, std::vec::Vec<u32>); // scope 0 at $DIR/inline-into-box-place.rs:+1:29: +1:43
-          _7 = (((_5.0: std::ptr::Unique<std::vec::Vec<u32>>).0: std::ptr::NonNull<std::vec::Vec<u32>>).0: *const std::vec::Vec<u32>); // scope 0 at $DIR/inline-into-box-place.rs:+1:33: +1:43
--         (*_7) = Vec::<u32>::new() -> [return: bb2, unwind: bb5]; // scope 0 at $DIR/inline-into-box-place.rs:+1:33: +1:43
-+         StorageLive(_8);                 // scope 0 at $DIR/inline-into-box-place.rs:+1:33: +1:43
-+         _8 = &mut (*_7);                 // scope 0 at $DIR/inline-into-box-place.rs:+1:33: +1:43
+          StorageLive(_5);                 // scope 0 at $DIR/inline_into_box_place.rs:+1:29: +1:43
+          _5 = ShallowInitBox(move _4, std::vec::Vec<u32>); // scope 0 at $DIR/inline_into_box_place.rs:+1:29: +1:43
+          _7 = (((_5.0: std::ptr::Unique<std::vec::Vec<u32>>).0: std::ptr::NonNull<std::vec::Vec<u32>>).0: *const std::vec::Vec<u32>); // scope 0 at $DIR/inline_into_box_place.rs:+1:33: +1:43
+-         (*_7) = Vec::<u32>::new() -> [return: bb2, unwind: bb5]; // scope 0 at $DIR/inline_into_box_place.rs:+1:33: +1:43
++         StorageLive(_8);                 // scope 0 at $DIR/inline_into_box_place.rs:+1:33: +1:43
++         _8 = &mut (*_7);                 // scope 0 at $DIR/inline_into_box_place.rs:+1:33: +1:43
 +         StorageLive(_9);                 // scope 3 at $SRC_DIR/alloc/src/vec/mod.rs:LL:COL
 +         _9 = const _;                    // scope 3 at $SRC_DIR/alloc/src/vec/mod.rs:LL:COL
                                            // mir::Constant
--                                          // + span: $DIR/inline-into-box-place.rs:8:33: 8:41
+-                                          // + span: $DIR/inline_into_box_place.rs:8:33: 8:41
 -                                          // + user_ty: UserType(1)
 -                                          // + literal: Const { ty: fn() -> Vec<u32> {Vec::<u32>::new}, val: Value(<ZST>) }
 -     }
@@ -53,29 +53,29 @@
 +         ((*_8).0: alloc::raw_vec::RawVec<u32>) = move _9; // scope 3 at $SRC_DIR/alloc/src/vec/mod.rs:LL:COL
 +         ((*_8).1: usize) = const 0_usize; // scope 3 at $SRC_DIR/alloc/src/vec/mod.rs:LL:COL
 +         StorageDead(_9);                 // scope 3 at $SRC_DIR/alloc/src/vec/mod.rs:LL:COL
-+         StorageDead(_8);                 // scope 0 at $DIR/inline-into-box-place.rs:+1:33: +1:43
-          _1 = move _5;                    // scope 0 at $DIR/inline-into-box-place.rs:+1:29: +1:43
-          StorageDead(_5);                 // scope 0 at $DIR/inline-into-box-place.rs:+1:42: +1:43
-          _0 = const ();                   // scope 0 at $DIR/inline-into-box-place.rs:+0:11: +2:2
--         drop(_1) -> [return: bb3, unwind: bb4]; // scope 0 at $DIR/inline-into-box-place.rs:+2:1: +2:2
-+         drop(_1) -> [return: bb2, unwind: bb3]; // scope 0 at $DIR/inline-into-box-place.rs:+2:1: +2:2
++         StorageDead(_8);                 // scope 0 at $DIR/inline_into_box_place.rs:+1:33: +1:43
+          _1 = move _5;                    // scope 0 at $DIR/inline_into_box_place.rs:+1:29: +1:43
+          StorageDead(_5);                 // scope 0 at $DIR/inline_into_box_place.rs:+1:42: +1:43
+          _0 = const ();                   // scope 0 at $DIR/inline_into_box_place.rs:+0:11: +2:2
+-         drop(_1) -> [return: bb3, unwind: bb4]; // scope 0 at $DIR/inline_into_box_place.rs:+2:1: +2:2
++         drop(_1) -> [return: bb2, unwind: bb3]; // scope 0 at $DIR/inline_into_box_place.rs:+2:1: +2:2
       }
   
 -     bb3: {
 +     bb2: {
-          StorageDead(_1);                 // scope 0 at $DIR/inline-into-box-place.rs:+2:1: +2:2
-          return;                          // scope 0 at $DIR/inline-into-box-place.rs:+2:2: +2:2
+          StorageDead(_1);                 // scope 0 at $DIR/inline_into_box_place.rs:+2:1: +2:2
+          return;                          // scope 0 at $DIR/inline_into_box_place.rs:+2:2: +2:2
       }
   
 -     bb4 (cleanup): {
 +     bb3 (cleanup): {
-          resume;                          // scope 0 at $DIR/inline-into-box-place.rs:+0:1: +2:2
+          resume;                          // scope 0 at $DIR/inline_into_box_place.rs:+0:1: +2:2
 -     }
 - 
 -     bb5 (cleanup): {
--         _6 = alloc::alloc::box_free::<Vec<u32>, std::alloc::Global>(move (_5.0: std::ptr::Unique<std::vec::Vec<u32>>), move (_5.1: std::alloc::Global)) -> bb4; // scope 0 at $DIR/inline-into-box-place.rs:+1:42: +1:43
+-         _6 = alloc::alloc::box_free::<Vec<u32>, std::alloc::Global>(move (_5.0: std::ptr::Unique<std::vec::Vec<u32>>), move (_5.1: std::alloc::Global)) -> bb4; // scope 0 at $DIR/inline_into_box_place.rs:+1:42: +1:43
 -                                          // mir::Constant
--                                          // + span: $DIR/inline-into-box-place.rs:8:42: 8:43
+-                                          // + span: $DIR/inline_into_box_place.rs:8:42: 8:43
 -                                          // + literal: Const { ty: unsafe fn(Unique<Vec<u32>>, std::alloc::Global) {alloc::alloc::box_free::<Vec<u32>, std::alloc::Global>}, val: Value(<ZST>) }
       }
   }
diff --git a/src/test/mir-opt/inline/inline-into-box-place.rs b/src/test/mir-opt/inline/inline_into_box_place.rs
similarity index 100%
rename from src/test/mir-opt/inline/inline-into-box-place.rs
rename to src/test/mir-opt/inline/inline_into_box_place.rs
diff --git a/src/test/mir-opt/inline/inline_options.main.Inline.after.mir b/src/test/mir-opt/inline/inline_options.main.Inline.after.mir
index 361b02715266..1c590be945c9 100644
--- a/src/test/mir-opt/inline/inline_options.main.Inline.after.mir
+++ b/src/test/mir-opt/inline/inline_options.main.Inline.after.mir
@@ -1,55 +1,55 @@
 // MIR for `main` after Inline
 
 fn main() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/inline-options.rs:+0:11: +0:11
-    let _1: ();                          // in scope 0 at $DIR/inline-options.rs:+1:5: +1:18
-    let _2: ();                          // in scope 0 at $DIR/inline-options.rs:+2:5: +2:21
-    scope 1 (inlined inlined::<u32>) {   // at $DIR/inline-options.rs:10:5: 10:21
-        let _3: ();                      // in scope 1 at $DIR/inline-options.rs:16:23: 16:26
-        let _4: ();                      // in scope 1 at $DIR/inline-options.rs:16:28: 16:31
-        let _5: ();                      // in scope 1 at $DIR/inline-options.rs:16:33: 16:36
+    let mut _0: ();                      // return place in scope 0 at $DIR/inline_options.rs:+0:11: +0:11
+    let _1: ();                          // in scope 0 at $DIR/inline_options.rs:+1:5: +1:18
+    let _2: ();                          // in scope 0 at $DIR/inline_options.rs:+2:5: +2:21
+    scope 1 (inlined inlined::<u32>) {   // at $DIR/inline_options.rs:10:5: 10:21
+        let _3: ();                      // in scope 1 at $DIR/inline_options.rs:16:23: 16:26
+        let _4: ();                      // in scope 1 at $DIR/inline_options.rs:16:28: 16:31
+        let _5: ();                      // in scope 1 at $DIR/inline_options.rs:16:33: 16:36
     }
 
     bb0: {
-        StorageLive(_1);                 // scope 0 at $DIR/inline-options.rs:+1:5: +1:18
-        _1 = not_inlined() -> bb1;       // scope 0 at $DIR/inline-options.rs:+1:5: +1:18
+        StorageLive(_1);                 // scope 0 at $DIR/inline_options.rs:+1:5: +1:18
+        _1 = not_inlined() -> bb1;       // scope 0 at $DIR/inline_options.rs:+1:5: +1:18
                                          // mir::Constant
-                                         // + span: $DIR/inline-options.rs:9:5: 9:16
+                                         // + span: $DIR/inline_options.rs:9:5: 9:16
                                          // + literal: Const { ty: fn() {not_inlined}, val: Value(<ZST>) }
     }
 
     bb1: {
-        StorageDead(_1);                 // scope 0 at $DIR/inline-options.rs:+1:18: +1:19
-        StorageLive(_2);                 // scope 0 at $DIR/inline-options.rs:+2:5: +2:21
-        StorageLive(_3);                 // scope 1 at $DIR/inline-options.rs:16:23: 16:26
-        _3 = g() -> bb2;                 // scope 1 at $DIR/inline-options.rs:16:23: 16:26
+        StorageDead(_1);                 // scope 0 at $DIR/inline_options.rs:+1:18: +1:19
+        StorageLive(_2);                 // scope 0 at $DIR/inline_options.rs:+2:5: +2:21
+        StorageLive(_3);                 // scope 1 at $DIR/inline_options.rs:16:23: 16:26
+        _3 = g() -> bb2;                 // scope 1 at $DIR/inline_options.rs:16:23: 16:26
                                          // mir::Constant
-                                         // + span: $DIR/inline-options.rs:16:23: 16:24
+                                         // + span: $DIR/inline_options.rs:16:23: 16:24
                                          // + literal: Const { ty: fn() {g}, val: Value(<ZST>) }
     }
 
     bb2: {
-        StorageDead(_3);                 // scope 1 at $DIR/inline-options.rs:16:26: 16:27
-        StorageLive(_4);                 // scope 1 at $DIR/inline-options.rs:16:28: 16:31
-        _4 = g() -> bb3;                 // scope 1 at $DIR/inline-options.rs:16:28: 16:31
+        StorageDead(_3);                 // scope 1 at $DIR/inline_options.rs:16:26: 16:27
+        StorageLive(_4);                 // scope 1 at $DIR/inline_options.rs:16:28: 16:31
+        _4 = g() -> bb3;                 // scope 1 at $DIR/inline_options.rs:16:28: 16:31
                                          // mir::Constant
-                                         // + span: $DIR/inline-options.rs:16:28: 16:29
+                                         // + span: $DIR/inline_options.rs:16:28: 16:29
                                          // + literal: Const { ty: fn() {g}, val: Value(<ZST>) }
     }
 
     bb3: {
-        StorageDead(_4);                 // scope 1 at $DIR/inline-options.rs:16:31: 16:32
-        StorageLive(_5);                 // scope 1 at $DIR/inline-options.rs:16:33: 16:36
-        _5 = g() -> bb4;                 // scope 1 at $DIR/inline-options.rs:16:33: 16:36
+        StorageDead(_4);                 // scope 1 at $DIR/inline_options.rs:16:31: 16:32
+        StorageLive(_5);                 // scope 1 at $DIR/inline_options.rs:16:33: 16:36
+        _5 = g() -> bb4;                 // scope 1 at $DIR/inline_options.rs:16:33: 16:36
                                          // mir::Constant
-                                         // + span: $DIR/inline-options.rs:16:33: 16:34
+                                         // + span: $DIR/inline_options.rs:16:33: 16:34
                                          // + literal: Const { ty: fn() {g}, val: Value(<ZST>) }
     }
 
     bb4: {
-        StorageDead(_5);                 // scope 1 at $DIR/inline-options.rs:16:36: 16:37
-        StorageDead(_2);                 // scope 0 at $DIR/inline-options.rs:+2:21: +2:22
-        _0 = const ();                   // scope 0 at $DIR/inline-options.rs:+0:11: +3:2
-        return;                          // scope 0 at $DIR/inline-options.rs:+3:2: +3:2
+        StorageDead(_5);                 // scope 1 at $DIR/inline_options.rs:16:36: 16:37
+        StorageDead(_2);                 // scope 0 at $DIR/inline_options.rs:+2:21: +2:22
+        _0 = const ();                   // scope 0 at $DIR/inline_options.rs:+0:11: +3:2
+        return;                          // scope 0 at $DIR/inline_options.rs:+3:2: +3:2
     }
 }
diff --git a/src/test/mir-opt/inline/inline-options.rs b/src/test/mir-opt/inline/inline_options.rs
similarity index 100%
rename from src/test/mir-opt/inline/inline-options.rs
rename to src/test/mir-opt/inline/inline_options.rs
diff --git a/src/test/mir-opt/inline/inline_retag.bar.Inline.after.mir b/src/test/mir-opt/inline/inline_retag.bar.Inline.after.mir
index 169e7f5c5d93..75af20d482dd 100644
--- a/src/test/mir-opt/inline/inline_retag.bar.Inline.after.mir
+++ b/src/test/mir-opt/inline/inline_retag.bar.Inline.after.mir
@@ -1,72 +1,72 @@
 // MIR for `bar` after Inline
 
 fn bar() -> bool {
-    let mut _0: bool;                    // return place in scope 0 at $DIR/inline-retag.rs:+0:13: +0:17
-    let _1: for<'a, 'b> fn(&'a i32, &'b i32) -> bool {foo}; // in scope 0 at $DIR/inline-retag.rs:+1:9: +1:10
-    let mut _2: for<'a, 'b> fn(&'a i32, &'b i32) -> bool {foo}; // in scope 0 at $DIR/inline-retag.rs:+2:5: +2:6
-    let mut _3: &i32;                    // in scope 0 at $DIR/inline-retag.rs:+2:7: +2:9
-    let _4: &i32;                        // in scope 0 at $DIR/inline-retag.rs:+2:7: +2:9
-    let _5: i32;                         // in scope 0 at $DIR/inline-retag.rs:+2:8: +2:9
-    let mut _6: &i32;                    // in scope 0 at $DIR/inline-retag.rs:+2:11: +2:14
-    let _7: &i32;                        // in scope 0 at $DIR/inline-retag.rs:+2:11: +2:14
-    let _8: i32;                         // in scope 0 at $DIR/inline-retag.rs:+2:12: +2:14
+    let mut _0: bool;                    // return place in scope 0 at $DIR/inline_retag.rs:+0:13: +0:17
+    let _1: for<'a, 'b> fn(&'a i32, &'b i32) -> bool {foo}; // in scope 0 at $DIR/inline_retag.rs:+1:9: +1:10
+    let mut _2: for<'a, 'b> fn(&'a i32, &'b i32) -> bool {foo}; // in scope 0 at $DIR/inline_retag.rs:+2:5: +2:6
+    let mut _3: &i32;                    // in scope 0 at $DIR/inline_retag.rs:+2:7: +2:9
+    let _4: &i32;                        // in scope 0 at $DIR/inline_retag.rs:+2:7: +2:9
+    let _5: i32;                         // in scope 0 at $DIR/inline_retag.rs:+2:8: +2:9
+    let mut _6: &i32;                    // in scope 0 at $DIR/inline_retag.rs:+2:11: +2:14
+    let _7: &i32;                        // in scope 0 at $DIR/inline_retag.rs:+2:11: +2:14
+    let _8: i32;                         // in scope 0 at $DIR/inline_retag.rs:+2:12: +2:14
     scope 1 {
-        debug f => _1;                   // in scope 1 at $DIR/inline-retag.rs:+1:9: +1:10
-        let mut _9: &i32;                // in scope 1 at $DIR/inline-retag.rs:+2:11: +2:14
-        let mut _10: &i32;               // in scope 1 at $DIR/inline-retag.rs:+2:7: +2:9
-        scope 2 (inlined foo) {          // at $DIR/inline-retag.rs:12:5: 12:15
-            debug x => _3;               // in scope 2 at $DIR/inline-retag.rs:16:8: 16:9
-            debug y => _6;               // in scope 2 at $DIR/inline-retag.rs:16:17: 16:18
-            let mut _11: i32;            // in scope 2 at $DIR/inline-retag.rs:17:5: 17:7
-            let mut _12: i32;            // in scope 2 at $DIR/inline-retag.rs:17:11: 17:13
+        debug f => _1;                   // in scope 1 at $DIR/inline_retag.rs:+1:9: +1:10
+        let mut _9: &i32;                // in scope 1 at $DIR/inline_retag.rs:+2:11: +2:14
+        let mut _10: &i32;               // in scope 1 at $DIR/inline_retag.rs:+2:7: +2:9
+        scope 2 (inlined foo) {          // at $DIR/inline_retag.rs:12:5: 12:15
+            debug x => _3;               // in scope 2 at $DIR/inline_retag.rs:16:8: 16:9
+            debug y => _6;               // in scope 2 at $DIR/inline_retag.rs:16:17: 16:18
+            let mut _11: i32;            // in scope 2 at $DIR/inline_retag.rs:17:5: 17:7
+            let mut _12: i32;            // in scope 2 at $DIR/inline_retag.rs:17:11: 17:13
         }
     }
 
     bb0: {
-        StorageLive(_1);                 // scope 0 at $DIR/inline-retag.rs:+1:9: +1:10
-        _1 = foo;                        // scope 0 at $DIR/inline-retag.rs:+1:13: +1:16
+        StorageLive(_1);                 // scope 0 at $DIR/inline_retag.rs:+1:9: +1:10
+        _1 = foo;                        // scope 0 at $DIR/inline_retag.rs:+1:13: +1:16
                                          // mir::Constant
-                                         // + span: $DIR/inline-retag.rs:11:13: 11:16
+                                         // + span: $DIR/inline_retag.rs:11:13: 11:16
                                          // + literal: Const { ty: for<'a, 'b> fn(&'a i32, &'b i32) -> bool {foo}, val: Value(<ZST>) }
-        StorageLive(_2);                 // scope 1 at $DIR/inline-retag.rs:+2:5: +2:6
-        _2 = _1;                         // scope 1 at $DIR/inline-retag.rs:+2:5: +2:6
-        StorageLive(_3);                 // scope 1 at $DIR/inline-retag.rs:+2:7: +2:9
-        StorageLive(_4);                 // scope 1 at $DIR/inline-retag.rs:+2:7: +2:9
-        _10 = const _;                   // scope 1 at $DIR/inline-retag.rs:+2:7: +2:9
+        StorageLive(_2);                 // scope 1 at $DIR/inline_retag.rs:+2:5: +2:6
+        _2 = _1;                         // scope 1 at $DIR/inline_retag.rs:+2:5: +2:6
+        StorageLive(_3);                 // scope 1 at $DIR/inline_retag.rs:+2:7: +2:9
+        StorageLive(_4);                 // scope 1 at $DIR/inline_retag.rs:+2:7: +2:9
+        _10 = const _;                   // scope 1 at $DIR/inline_retag.rs:+2:7: +2:9
                                          // mir::Constant
-                                         // + span: $DIR/inline-retag.rs:12:7: 12:9
+                                         // + span: $DIR/inline_retag.rs:12:7: 12:9
                                          // + literal: Const { ty: &i32, val: Unevaluated(bar, [], Some(promoted[1])) }
-        Retag(_10);                      // scope 1 at $DIR/inline-retag.rs:+2:7: +2:9
-        _4 = &(*_10);                    // scope 1 at $DIR/inline-retag.rs:+2:7: +2:9
-        Retag(_4);                       // scope 1 at $DIR/inline-retag.rs:+2:7: +2:9
-        _3 = &(*_4);                     // scope 1 at $DIR/inline-retag.rs:+2:7: +2:9
-        Retag(_3);                       // scope 1 at $DIR/inline-retag.rs:+2:7: +2:9
-        StorageLive(_6);                 // scope 1 at $DIR/inline-retag.rs:+2:11: +2:14
-        StorageLive(_7);                 // scope 1 at $DIR/inline-retag.rs:+2:11: +2:14
-        _9 = const _;                    // scope 1 at $DIR/inline-retag.rs:+2:11: +2:14
+        Retag(_10);                      // scope 1 at $DIR/inline_retag.rs:+2:7: +2:9
+        _4 = &(*_10);                    // scope 1 at $DIR/inline_retag.rs:+2:7: +2:9
+        Retag(_4);                       // scope 1 at $DIR/inline_retag.rs:+2:7: +2:9
+        _3 = &(*_4);                     // scope 1 at $DIR/inline_retag.rs:+2:7: +2:9
+        Retag(_3);                       // scope 1 at $DIR/inline_retag.rs:+2:7: +2:9
+        StorageLive(_6);                 // scope 1 at $DIR/inline_retag.rs:+2:11: +2:14
+        StorageLive(_7);                 // scope 1 at $DIR/inline_retag.rs:+2:11: +2:14
+        _9 = const _;                    // scope 1 at $DIR/inline_retag.rs:+2:11: +2:14
                                          // mir::Constant
-                                         // + span: $DIR/inline-retag.rs:12:11: 12:14
+                                         // + span: $DIR/inline_retag.rs:12:11: 12:14
                                          // + literal: Const { ty: &i32, val: Unevaluated(bar, [], Some(promoted[0])) }
-        Retag(_9);                       // scope 1 at $DIR/inline-retag.rs:+2:11: +2:14
-        _7 = &(*_9);                     // scope 1 at $DIR/inline-retag.rs:+2:11: +2:14
-        Retag(_7);                       // scope 1 at $DIR/inline-retag.rs:+2:11: +2:14
-        _6 = &(*_7);                     // scope 1 at $DIR/inline-retag.rs:+2:11: +2:14
-        Retag(_6);                       // scope 1 at $DIR/inline-retag.rs:+2:11: +2:14
-        Retag(_3);                       // scope 2 at $DIR/inline-retag.rs:16:8: 16:9
-        Retag(_6);                       // scope 2 at $DIR/inline-retag.rs:16:17: 16:18
-        StorageLive(_11);                // scope 2 at $DIR/inline-retag.rs:17:5: 17:7
-        _11 = (*_3);                     // scope 2 at $DIR/inline-retag.rs:17:5: 17:7
-        StorageLive(_12);                // scope 2 at $DIR/inline-retag.rs:17:11: 17:13
-        _12 = (*_6);                     // scope 2 at $DIR/inline-retag.rs:17:11: 17:13
-        _0 = Eq(move _11, move _12);     // scope 2 at $DIR/inline-retag.rs:17:5: 17:13
-        StorageDead(_12);                // scope 2 at $DIR/inline-retag.rs:17:12: 17:13
-        StorageDead(_11);                // scope 2 at $DIR/inline-retag.rs:17:12: 17:13
-        StorageDead(_6);                 // scope 1 at $DIR/inline-retag.rs:+2:14: +2:15
-        StorageDead(_3);                 // scope 1 at $DIR/inline-retag.rs:+2:14: +2:15
-        StorageDead(_2);                 // scope 1 at $DIR/inline-retag.rs:+2:14: +2:15
-        StorageDead(_1);                 // scope 0 at $DIR/inline-retag.rs:+3:1: +3:2
-        StorageDead(_7);                 // scope 0 at $DIR/inline-retag.rs:+3:1: +3:2
-        StorageDead(_4);                 // scope 0 at $DIR/inline-retag.rs:+3:1: +3:2
-        return;                          // scope 0 at $DIR/inline-retag.rs:+3:2: +3:2
+        Retag(_9);                       // scope 1 at $DIR/inline_retag.rs:+2:11: +2:14
+        _7 = &(*_9);                     // scope 1 at $DIR/inline_retag.rs:+2:11: +2:14
+        Retag(_7);                       // scope 1 at $DIR/inline_retag.rs:+2:11: +2:14
+        _6 = &(*_7);                     // scope 1 at $DIR/inline_retag.rs:+2:11: +2:14
+        Retag(_6);                       // scope 1 at $DIR/inline_retag.rs:+2:11: +2:14
+        Retag(_3);                       // scope 2 at $DIR/inline_retag.rs:16:8: 16:9
+        Retag(_6);                       // scope 2 at $DIR/inline_retag.rs:16:17: 16:18
+        StorageLive(_11);                // scope 2 at $DIR/inline_retag.rs:17:5: 17:7
+        _11 = (*_3);                     // scope 2 at $DIR/inline_retag.rs:17:5: 17:7
+        StorageLive(_12);                // scope 2 at $DIR/inline_retag.rs:17:11: 17:13
+        _12 = (*_6);                     // scope 2 at $DIR/inline_retag.rs:17:11: 17:13
+        _0 = Eq(move _11, move _12);     // scope 2 at $DIR/inline_retag.rs:17:5: 17:13
+        StorageDead(_12);                // scope 2 at $DIR/inline_retag.rs:17:12: 17:13
+        StorageDead(_11);                // scope 2 at $DIR/inline_retag.rs:17:12: 17:13
+        StorageDead(_6);                 // scope 1 at $DIR/inline_retag.rs:+2:14: +2:15
+        StorageDead(_3);                 // scope 1 at $DIR/inline_retag.rs:+2:14: +2:15
+        StorageDead(_2);                 // scope 1 at $DIR/inline_retag.rs:+2:14: +2:15
+        StorageDead(_1);                 // scope 0 at $DIR/inline_retag.rs:+3:1: +3:2
+        StorageDead(_7);                 // scope 0 at $DIR/inline_retag.rs:+3:1: +3:2
+        StorageDead(_4);                 // scope 0 at $DIR/inline_retag.rs:+3:1: +3:2
+        return;                          // scope 0 at $DIR/inline_retag.rs:+3:2: +3:2
     }
 }
diff --git a/src/test/mir-opt/inline/inline-retag.rs b/src/test/mir-opt/inline/inline_retag.rs
similarity index 100%
rename from src/test/mir-opt/inline/inline-retag.rs
rename to src/test/mir-opt/inline/inline_retag.rs
diff --git a/src/test/mir-opt/inline/inline_shims.clone.Inline.diff b/src/test/mir-opt/inline/inline_shims.clone.Inline.diff
index d691e90b7dac..969573ba3253 100644
--- a/src/test/mir-opt/inline/inline_shims.clone.Inline.diff
+++ b/src/test/mir-opt/inline/inline_shims.clone.Inline.diff
@@ -2,25 +2,25 @@
 + // MIR for `clone` after Inline
   
   fn clone(_1: fn(A, B)) -> fn(A, B) {
-      debug f => _1;                       // in scope 0 at $DIR/inline-shims.rs:+0:20: +0:21
-      let mut _0: fn(A, B);                // return place in scope 0 at $DIR/inline-shims.rs:+0:36: +0:44
-      let mut _2: &fn(A, B);               // in scope 0 at $DIR/inline-shims.rs:+1:5: +1:14
-+     scope 1 (inlined <fn(A, B) as Clone>::clone - shim(fn(A, B))) { // at $DIR/inline-shims.rs:6:5: 6:14
+      debug f => _1;                       // in scope 0 at $DIR/inline_shims.rs:+0:20: +0:21
+      let mut _0: fn(A, B);                // return place in scope 0 at $DIR/inline_shims.rs:+0:36: +0:44
+      let mut _2: &fn(A, B);               // in scope 0 at $DIR/inline_shims.rs:+1:5: +1:14
++     scope 1 (inlined <fn(A, B) as Clone>::clone - shim(fn(A, B))) { // at $DIR/inline_shims.rs:6:5: 6:14
 +     }
   
       bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/inline-shims.rs:+1:5: +1:14
-          _2 = &_1;                        // scope 0 at $DIR/inline-shims.rs:+1:5: +1:14
--         _0 = <fn(A, B) as Clone>::clone(move _2) -> bb1; // scope 0 at $DIR/inline-shims.rs:+1:5: +1:14
+          StorageLive(_2);                 // scope 0 at $DIR/inline_shims.rs:+1:5: +1:14
+          _2 = &_1;                        // scope 0 at $DIR/inline_shims.rs:+1:5: +1:14
+-         _0 = <fn(A, B) as Clone>::clone(move _2) -> bb1; // scope 0 at $DIR/inline_shims.rs:+1:5: +1:14
 -                                          // mir::Constant
--                                          // + span: $DIR/inline-shims.rs:6:7: 6:12
+-                                          // + span: $DIR/inline_shims.rs:6:7: 6:12
 -                                          // + literal: Const { ty: for<'a> fn(&'a fn(A, B)) -> fn(A, B) {<fn(A, B) as Clone>::clone}, val: Value(<ZST>) }
 -     }
 - 
 -     bb1: {
 +         _0 = (*_2);                      // scope 1 at $SRC_DIR/core/src/clone.rs:LL:COL
-          StorageDead(_2);                 // scope 0 at $DIR/inline-shims.rs:+1:13: +1:14
-          return;                          // scope 0 at $DIR/inline-shims.rs:+2:2: +2:2
+          StorageDead(_2);                 // scope 0 at $DIR/inline_shims.rs:+1:13: +1:14
+          return;                          // scope 0 at $DIR/inline_shims.rs:+2:2: +2:2
       }
   }
   
diff --git a/src/test/mir-opt/inline/inline_shims.drop.Inline.diff b/src/test/mir-opt/inline/inline_shims.drop.Inline.diff
index f7b1cde80bdc..7a54beca2336 100644
--- a/src/test/mir-opt/inline/inline_shims.drop.Inline.diff
+++ b/src/test/mir-opt/inline/inline_shims.drop.Inline.diff
@@ -2,51 +2,51 @@
 + // MIR for `drop` after Inline
   
   fn drop(_1: *mut Vec<A>, _2: *mut Option<B>) -> () {
-      debug a => _1;                       // in scope 0 at $DIR/inline-shims.rs:+0:19: +0:20
-      debug b => _2;                       // in scope 0 at $DIR/inline-shims.rs:+0:35: +0:36
-      let mut _0: ();                      // return place in scope 0 at $DIR/inline-shims.rs:+0:54: +0:54
-      let _3: ();                          // in scope 0 at $DIR/inline-shims.rs:+1:14: +1:40
-      let mut _4: *mut std::vec::Vec<A>;   // in scope 0 at $DIR/inline-shims.rs:+1:38: +1:39
-      let mut _5: *mut std::option::Option<B>; // in scope 0 at $DIR/inline-shims.rs:+2:38: +2:39
+      debug a => _1;                       // in scope 0 at $DIR/inline_shims.rs:+0:19: +0:20
+      debug b => _2;                       // in scope 0 at $DIR/inline_shims.rs:+0:35: +0:36
+      let mut _0: ();                      // return place in scope 0 at $DIR/inline_shims.rs:+0:54: +0:54
+      let _3: ();                          // in scope 0 at $DIR/inline_shims.rs:+1:14: +1:40
+      let mut _4: *mut std::vec::Vec<A>;   // in scope 0 at $DIR/inline_shims.rs:+1:38: +1:39
+      let mut _5: *mut std::option::Option<B>; // in scope 0 at $DIR/inline_shims.rs:+2:38: +2:39
       scope 1 {
       }
       scope 2 {
-+         scope 3 (inlined std::ptr::drop_in_place::<Option<B>> - shim(Some(Option<B>))) { // at $DIR/inline-shims.rs:12:14: 12:40
++         scope 3 (inlined std::ptr::drop_in_place::<Option<B>> - shim(Some(Option<B>))) { // at $DIR/inline_shims.rs:12:14: 12:40
 +             let mut _6: isize;           // in scope 3 at $SRC_DIR/core/src/ptr/mod.rs:LL:COL
 +             let mut _7: isize;           // in scope 3 at $SRC_DIR/core/src/ptr/mod.rs:LL:COL
 +         }
       }
   
       bb0: {
-          StorageLive(_3);                 // scope 0 at $DIR/inline-shims.rs:+1:5: +1:42
-          StorageLive(_4);                 // scope 1 at $DIR/inline-shims.rs:+1:38: +1:39
-          _4 = _1;                         // scope 1 at $DIR/inline-shims.rs:+1:38: +1:39
-          _3 = std::ptr::drop_in_place::<Vec<A>>(move _4) -> bb1; // scope 1 at $DIR/inline-shims.rs:+1:14: +1:40
+          StorageLive(_3);                 // scope 0 at $DIR/inline_shims.rs:+1:5: +1:42
+          StorageLive(_4);                 // scope 1 at $DIR/inline_shims.rs:+1:38: +1:39
+          _4 = _1;                         // scope 1 at $DIR/inline_shims.rs:+1:38: +1:39
+          _3 = std::ptr::drop_in_place::<Vec<A>>(move _4) -> bb1; // scope 1 at $DIR/inline_shims.rs:+1:14: +1:40
                                            // mir::Constant
-                                           // + span: $DIR/inline-shims.rs:11:14: 11:37
+                                           // + span: $DIR/inline_shims.rs:11:14: 11:37
                                            // + literal: Const { ty: unsafe fn(*mut Vec<A>) {std::ptr::drop_in_place::<Vec<A>>}, val: Value(<ZST>) }
       }
   
       bb1: {
-          StorageDead(_4);                 // scope 1 at $DIR/inline-shims.rs:+1:39: +1:40
-          StorageDead(_3);                 // scope 0 at $DIR/inline-shims.rs:+1:41: +1:42
-          StorageLive(_5);                 // scope 2 at $DIR/inline-shims.rs:+2:38: +2:39
-          _5 = _2;                         // scope 2 at $DIR/inline-shims.rs:+2:38: +2:39
--         _0 = std::ptr::drop_in_place::<Option<B>>(move _5) -> bb2; // scope 2 at $DIR/inline-shims.rs:+2:14: +2:40
+          StorageDead(_4);                 // scope 1 at $DIR/inline_shims.rs:+1:39: +1:40
+          StorageDead(_3);                 // scope 0 at $DIR/inline_shims.rs:+1:41: +1:42
+          StorageLive(_5);                 // scope 2 at $DIR/inline_shims.rs:+2:38: +2:39
+          _5 = _2;                         // scope 2 at $DIR/inline_shims.rs:+2:38: +2:39
+-         _0 = std::ptr::drop_in_place::<Option<B>>(move _5) -> bb2; // scope 2 at $DIR/inline_shims.rs:+2:14: +2:40
 -                                          // mir::Constant
--                                          // + span: $DIR/inline-shims.rs:12:14: 12:37
+-                                          // + span: $DIR/inline_shims.rs:12:14: 12:37
 -                                          // + literal: Const { ty: unsafe fn(*mut Option<B>) {std::ptr::drop_in_place::<Option<B>>}, val: Value(<ZST>) }
-+         StorageLive(_6);                 // scope 2 at $DIR/inline-shims.rs:+2:14: +2:40
-+         StorageLive(_7);                 // scope 2 at $DIR/inline-shims.rs:+2:14: +2:40
++         StorageLive(_6);                 // scope 2 at $DIR/inline_shims.rs:+2:14: +2:40
++         StorageLive(_7);                 // scope 2 at $DIR/inline_shims.rs:+2:14: +2:40
 +         _6 = discriminant((*_5));        // scope 3 at $SRC_DIR/core/src/ptr/mod.rs:LL:COL
 +         switchInt(move _6) -> [0_isize: bb2, otherwise: bb3]; // scope 3 at $SRC_DIR/core/src/ptr/mod.rs:LL:COL
       }
   
       bb2: {
-+         StorageDead(_7);                 // scope 2 at $DIR/inline-shims.rs:+2:14: +2:40
-+         StorageDead(_6);                 // scope 2 at $DIR/inline-shims.rs:+2:14: +2:40
-          StorageDead(_5);                 // scope 2 at $DIR/inline-shims.rs:+2:39: +2:40
-          return;                          // scope 0 at $DIR/inline-shims.rs:+3:2: +3:2
++         StorageDead(_7);                 // scope 2 at $DIR/inline_shims.rs:+2:14: +2:40
++         StorageDead(_6);                 // scope 2 at $DIR/inline_shims.rs:+2:14: +2:40
+          StorageDead(_5);                 // scope 2 at $DIR/inline_shims.rs:+2:39: +2:40
+          return;                          // scope 0 at $DIR/inline_shims.rs:+3:2: +3:2
 +     }
 + 
 +     bb3: {
diff --git a/src/test/mir-opt/inline/inline-shims.rs b/src/test/mir-opt/inline/inline_shims.rs
similarity index 100%
rename from src/test/mir-opt/inline/inline-shims.rs
rename to src/test/mir-opt/inline/inline_shims.rs
diff --git a/src/test/mir-opt/inline/inline_specialization.main.Inline.diff b/src/test/mir-opt/inline/inline_specialization.main.Inline.diff
index fdf2a1e1ff93..af08296edea5 100644
--- a/src/test/mir-opt/inline/inline_specialization.main.Inline.diff
+++ b/src/test/mir-opt/inline/inline_specialization.main.Inline.diff
@@ -2,27 +2,27 @@
 + // MIR for `main` after Inline
   
   fn main() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/inline-specialization.rs:+0:11: +0:11
-      let _1: u32;                         // in scope 0 at $DIR/inline-specialization.rs:+1:9: +1:10
+      let mut _0: ();                      // return place in scope 0 at $DIR/inline_specialization.rs:+0:11: +0:11
+      let _1: u32;                         // in scope 0 at $DIR/inline_specialization.rs:+1:9: +1:10
       scope 1 {
-          debug x => _1;                   // in scope 1 at $DIR/inline-specialization.rs:+1:9: +1:10
+          debug x => _1;                   // in scope 1 at $DIR/inline_specialization.rs:+1:9: +1:10
       }
-+     scope 2 (inlined <Vec<()> as Foo>::bar) { // at $DIR/inline-specialization.rs:5:13: 5:38
++     scope 2 (inlined <Vec<()> as Foo>::bar) { // at $DIR/inline_specialization.rs:5:13: 5:38
 +     }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/inline-specialization.rs:+1:9: +1:10
--         _1 = <Vec<()> as Foo>::bar() -> bb1; // scope 0 at $DIR/inline-specialization.rs:+1:13: +1:38
+          StorageLive(_1);                 // scope 0 at $DIR/inline_specialization.rs:+1:9: +1:10
+-         _1 = <Vec<()> as Foo>::bar() -> bb1; // scope 0 at $DIR/inline_specialization.rs:+1:13: +1:38
 -                                          // mir::Constant
--                                          // + span: $DIR/inline-specialization.rs:5:13: 5:36
+-                                          // + span: $DIR/inline_specialization.rs:5:13: 5:36
 -                                          // + literal: Const { ty: fn() -> u32 {<Vec<()> as Foo>::bar}, val: Value(<ZST>) }
 -     }
 - 
 -     bb1: {
-+         _1 = const 123_u32;              // scope 2 at $DIR/inline-specialization.rs:14:31: 14:34
-          _0 = const ();                   // scope 0 at $DIR/inline-specialization.rs:+0:11: +2:2
-          StorageDead(_1);                 // scope 0 at $DIR/inline-specialization.rs:+2:1: +2:2
-          return;                          // scope 0 at $DIR/inline-specialization.rs:+2:2: +2:2
++         _1 = const 123_u32;              // scope 2 at $DIR/inline_specialization.rs:14:31: 14:34
+          _0 = const ();                   // scope 0 at $DIR/inline_specialization.rs:+0:11: +2:2
+          StorageDead(_1);                 // scope 0 at $DIR/inline_specialization.rs:+2:1: +2:2
+          return;                          // scope 0 at $DIR/inline_specialization.rs:+2:2: +2:2
       }
   }
   
diff --git a/src/test/mir-opt/inline/inline-specialization.rs b/src/test/mir-opt/inline/inline_specialization.rs
similarity index 100%
rename from src/test/mir-opt/inline/inline-specialization.rs
rename to src/test/mir-opt/inline/inline_specialization.rs
diff --git a/src/test/mir-opt/inline/inline-trait-method.rs b/src/test/mir-opt/inline/inline_trait_method.rs
similarity index 100%
rename from src/test/mir-opt/inline/inline-trait-method.rs
rename to src/test/mir-opt/inline/inline_trait_method.rs
diff --git a/src/test/mir-opt/inline/inline_trait_method.test.Inline.after.mir b/src/test/mir-opt/inline/inline_trait_method.test.Inline.after.mir
index 89eefc292691..637bf282a65b 100644
--- a/src/test/mir-opt/inline/inline_trait_method.test.Inline.after.mir
+++ b/src/test/mir-opt/inline/inline_trait_method.test.Inline.after.mir
@@ -1,21 +1,21 @@
 // MIR for `test` after Inline
 
 fn test(_1: &dyn X) -> u32 {
-    debug x => _1;                       // in scope 0 at $DIR/inline-trait-method.rs:+0:9: +0:10
-    let mut _0: u32;                     // return place in scope 0 at $DIR/inline-trait-method.rs:+0:23: +0:26
-    let mut _2: &dyn X;                  // in scope 0 at $DIR/inline-trait-method.rs:+1:5: +1:10
+    debug x => _1;                       // in scope 0 at $DIR/inline_trait_method.rs:+0:9: +0:10
+    let mut _0: u32;                     // return place in scope 0 at $DIR/inline_trait_method.rs:+0:23: +0:26
+    let mut _2: &dyn X;                  // in scope 0 at $DIR/inline_trait_method.rs:+1:5: +1:10
 
     bb0: {
-        StorageLive(_2);                 // scope 0 at $DIR/inline-trait-method.rs:+1:5: +1:10
-        _2 = &(*_1);                     // scope 0 at $DIR/inline-trait-method.rs:+1:5: +1:10
-        _0 = <dyn X as X>::y(move _2) -> bb1; // scope 0 at $DIR/inline-trait-method.rs:+1:5: +1:10
+        StorageLive(_2);                 // scope 0 at $DIR/inline_trait_method.rs:+1:5: +1:10
+        _2 = &(*_1);                     // scope 0 at $DIR/inline_trait_method.rs:+1:5: +1:10
+        _0 = <dyn X as X>::y(move _2) -> bb1; // scope 0 at $DIR/inline_trait_method.rs:+1:5: +1:10
                                          // mir::Constant
-                                         // + span: $DIR/inline-trait-method.rs:9:7: 9:8
+                                         // + span: $DIR/inline_trait_method.rs:9:7: 9:8
                                          // + literal: Const { ty: for<'a> fn(&'a dyn X) -> u32 {<dyn X as X>::y}, val: Value(<ZST>) }
     }
 
     bb1: {
-        StorageDead(_2);                 // scope 0 at $DIR/inline-trait-method.rs:+1:9: +1:10
-        return;                          // scope 0 at $DIR/inline-trait-method.rs:+2:2: +2:2
+        StorageDead(_2);                 // scope 0 at $DIR/inline_trait_method.rs:+1:9: +1:10
+        return;                          // scope 0 at $DIR/inline_trait_method.rs:+2:2: +2:2
     }
 }
diff --git a/src/test/mir-opt/inline/inline-trait-method_2.rs b/src/test/mir-opt/inline/inline_trait_method_2.rs
similarity index 100%
rename from src/test/mir-opt/inline/inline-trait-method_2.rs
rename to src/test/mir-opt/inline/inline_trait_method_2.rs
diff --git a/src/test/mir-opt/inline/inline_trait_method_2.test2.Inline.after.mir b/src/test/mir-opt/inline/inline_trait_method_2.test2.Inline.after.mir
index 3d05869fa513..dab8bb9a0c62 100644
--- a/src/test/mir-opt/inline/inline_trait_method_2.test2.Inline.after.mir
+++ b/src/test/mir-opt/inline/inline_trait_method_2.test2.Inline.after.mir
@@ -1,32 +1,32 @@
 // MIR for `test2` after Inline
 
 fn test2(_1: &dyn X) -> bool {
-    debug x => _1;                       // in scope 0 at $DIR/inline-trait-method_2.rs:+0:10: +0:11
-    let mut _0: bool;                    // return place in scope 0 at $DIR/inline-trait-method_2.rs:+0:24: +0:28
-    let mut _2: &dyn X;                  // in scope 0 at $DIR/inline-trait-method_2.rs:+1:10: +1:11
-    let mut _3: &dyn X;                  // in scope 0 at $DIR/inline-trait-method_2.rs:+1:10: +1:11
-    scope 1 (inlined test) {             // at $DIR/inline-trait-method_2.rs:5:5: 5:12
-        debug x => _2;                   // in scope 1 at $DIR/inline-trait-method_2.rs:9:9: 9:10
-        let mut _4: &dyn X;              // in scope 1 at $DIR/inline-trait-method_2.rs:10:5: 10:10
+    debug x => _1;                       // in scope 0 at $DIR/inline_trait_method_2.rs:+0:10: +0:11
+    let mut _0: bool;                    // return place in scope 0 at $DIR/inline_trait_method_2.rs:+0:24: +0:28
+    let mut _2: &dyn X;                  // in scope 0 at $DIR/inline_trait_method_2.rs:+1:10: +1:11
+    let mut _3: &dyn X;                  // in scope 0 at $DIR/inline_trait_method_2.rs:+1:10: +1:11
+    scope 1 (inlined test) {             // at $DIR/inline_trait_method_2.rs:5:5: 5:12
+        debug x => _2;                   // in scope 1 at $DIR/inline_trait_method_2.rs:9:9: 9:10
+        let mut _4: &dyn X;              // in scope 1 at $DIR/inline_trait_method_2.rs:10:5: 10:10
     }
 
     bb0: {
-        StorageLive(_2);                 // scope 0 at $DIR/inline-trait-method_2.rs:+1:10: +1:11
-        StorageLive(_3);                 // scope 0 at $DIR/inline-trait-method_2.rs:+1:10: +1:11
-        _3 = &(*_1);                     // scope 0 at $DIR/inline-trait-method_2.rs:+1:10: +1:11
-        _2 = move _3 as &dyn X (Pointer(Unsize)); // scope 0 at $DIR/inline-trait-method_2.rs:+1:10: +1:11
-        StorageDead(_3);                 // scope 0 at $DIR/inline-trait-method_2.rs:+1:10: +1:11
-        StorageLive(_4);                 // scope 1 at $DIR/inline-trait-method_2.rs:10:5: 10:10
-        _4 = _2;                         // scope 1 at $DIR/inline-trait-method_2.rs:10:5: 10:10
-        _0 = <dyn X as X>::y(move _4) -> bb1; // scope 1 at $DIR/inline-trait-method_2.rs:10:5: 10:10
+        StorageLive(_2);                 // scope 0 at $DIR/inline_trait_method_2.rs:+1:10: +1:11
+        StorageLive(_3);                 // scope 0 at $DIR/inline_trait_method_2.rs:+1:10: +1:11
+        _3 = &(*_1);                     // scope 0 at $DIR/inline_trait_method_2.rs:+1:10: +1:11
+        _2 = move _3 as &dyn X (Pointer(Unsize)); // scope 0 at $DIR/inline_trait_method_2.rs:+1:10: +1:11
+        StorageDead(_3);                 // scope 0 at $DIR/inline_trait_method_2.rs:+1:10: +1:11
+        StorageLive(_4);                 // scope 1 at $DIR/inline_trait_method_2.rs:10:5: 10:10
+        _4 = _2;                         // scope 1 at $DIR/inline_trait_method_2.rs:10:5: 10:10
+        _0 = <dyn X as X>::y(move _4) -> bb1; // scope 1 at $DIR/inline_trait_method_2.rs:10:5: 10:10
                                          // mir::Constant
-                                         // + span: $DIR/inline-trait-method_2.rs:10:7: 10:8
+                                         // + span: $DIR/inline_trait_method_2.rs:10:7: 10:8
                                          // + literal: Const { ty: for<'a> fn(&'a dyn X) -> bool {<dyn X as X>::y}, val: Value(<ZST>) }
     }
 
     bb1: {
-        StorageDead(_4);                 // scope 1 at $DIR/inline-trait-method_2.rs:10:9: 10:10
-        StorageDead(_2);                 // scope 0 at $DIR/inline-trait-method_2.rs:+1:11: +1:12
-        return;                          // scope 0 at $DIR/inline-trait-method_2.rs:+2:2: +2:2
+        StorageDead(_4);                 // scope 1 at $DIR/inline_trait_method_2.rs:10:9: 10:10
+        StorageDead(_2);                 // scope 0 at $DIR/inline_trait_method_2.rs:+1:11: +1:12
+        return;                          // scope 0 at $DIR/inline_trait_method_2.rs:+2:2: +2:2
     }
 }
diff --git a/src/test/mir-opt/inline/issue_58867_inline_as_ref_as_mut.a.Inline.after.mir b/src/test/mir-opt/inline/issue_58867_inline_as_ref_as_mut.a.Inline.after.mir
index 5168ae031f04..777681e1ce7e 100644
--- a/src/test/mir-opt/inline/issue_58867_inline_as_ref_as_mut.a.Inline.after.mir
+++ b/src/test/mir-opt/inline/issue_58867_inline_as_ref_as_mut.a.Inline.after.mir
@@ -1,30 +1,30 @@
 // MIR for `a` after Inline
 
 fn a(_1: &mut [T]) -> &mut [T] {
-    debug x => _1;                       // in scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+0:13: +0:14
-    let mut _0: &mut [T];                // return place in scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+0:29: +0:37
-    let mut _2: &mut [T];                // in scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-    let mut _3: &mut [T];                // in scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-    let mut _4: &mut [T];                // in scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-    scope 1 (inlined <[T] as AsMut<[T]>>::as_mut) { // at $DIR/issue-58867-inline-as-ref-as-mut.rs:3:5: 3:15
+    debug x => _1;                       // in scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+0:13: +0:14
+    let mut _0: &mut [T];                // return place in scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+0:29: +0:37
+    let mut _2: &mut [T];                // in scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+    let mut _3: &mut [T];                // in scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+    let mut _4: &mut [T];                // in scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+    scope 1 (inlined <[T] as AsMut<[T]>>::as_mut) { // at $DIR/issue_58867_inline_as_ref_as_mut.rs:3:5: 3:15
         debug self => _4;                // in scope 1 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
         let mut _5: &mut [T];            // in scope 1 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
     }
 
     bb0: {
-        StorageLive(_2);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-        StorageLive(_3);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-        StorageLive(_4);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-        _4 = &mut (*_1);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
+        StorageLive(_2);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+        StorageLive(_3);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+        StorageLive(_4);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+        _4 = &mut (*_1);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
         StorageLive(_5);                 // scope 1 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
         _5 = &mut (*_4);                 // scope 1 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
         _3 = &mut (*_5);                 // scope 1 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
         StorageDead(_5);                 // scope 1 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
-        _2 = &mut (*_3);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-        StorageDead(_4);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:14: +1:15
-        _0 = &mut (*_2);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-        StorageDead(_3);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+2:1: +2:2
-        StorageDead(_2);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+2:1: +2:2
-        return;                          // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+2:2: +2:2
+        _2 = &mut (*_3);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+        StorageDead(_4);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:14: +1:15
+        _0 = &mut (*_2);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+        StorageDead(_3);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+2:1: +2:2
+        StorageDead(_2);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+2:1: +2:2
+        return;                          // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+2:2: +2:2
     }
 }
diff --git a/src/test/mir-opt/inline/issue_58867_inline_as_ref_as_mut.b.Inline.after.mir b/src/test/mir-opt/inline/issue_58867_inline_as_ref_as_mut.b.Inline.after.mir
index 06d442ae88b9..83545c991000 100644
--- a/src/test/mir-opt/inline/issue_58867_inline_as_ref_as_mut.b.Inline.after.mir
+++ b/src/test/mir-opt/inline/issue_58867_inline_as_ref_as_mut.b.Inline.after.mir
@@ -1,12 +1,12 @@
 // MIR for `b` after Inline
 
 fn b(_1: &mut Box<T>) -> &mut T {
-    debug x => _1;                       // in scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+0:13: +0:14
-    let mut _0: &mut T;                  // return place in scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+0:32: +0:38
-    let mut _2: &mut T;                  // in scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-    let mut _3: &mut T;                  // in scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-    let mut _4: &mut std::boxed::Box<T>; // in scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-    scope 1 (inlined <Box<T> as AsMut<T>>::as_mut) { // at $DIR/issue-58867-inline-as-ref-as-mut.rs:8:5: 8:15
+    debug x => _1;                       // in scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+0:13: +0:14
+    let mut _0: &mut T;                  // return place in scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+0:32: +0:38
+    let mut _2: &mut T;                  // in scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+    let mut _3: &mut T;                  // in scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+    let mut _4: &mut std::boxed::Box<T>; // in scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+    scope 1 (inlined <Box<T> as AsMut<T>>::as_mut) { // at $DIR/issue_58867_inline_as_ref_as_mut.rs:8:5: 8:15
         debug self => _4;                // in scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
         let mut _5: &mut T;              // in scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
         let mut _6: &mut T;              // in scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
@@ -15,10 +15,10 @@ fn b(_1: &mut Box<T>) -> &mut T {
     }
 
     bb0: {
-        StorageLive(_2);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-        StorageLive(_3);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-        StorageLive(_4);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-        _4 = &mut (*_1);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
+        StorageLive(_2);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+        StorageLive(_3);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+        StorageLive(_4);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+        _4 = &mut (*_1);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
         StorageLive(_5);                 // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
         StorageLive(_6);                 // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
         _7 = deref_copy (*_4);           // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
@@ -28,11 +28,11 @@ fn b(_1: &mut Box<T>) -> &mut T {
         _3 = &mut (*_5);                 // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
         StorageDead(_6);                 // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
         StorageDead(_5);                 // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
-        _2 = &mut (*_3);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-        StorageDead(_4);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:14: +1:15
-        _0 = &mut (*_2);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-        StorageDead(_3);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+2:1: +2:2
-        StorageDead(_2);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+2:1: +2:2
-        return;                          // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+2:2: +2:2
+        _2 = &mut (*_3);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+        StorageDead(_4);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:14: +1:15
+        _0 = &mut (*_2);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+        StorageDead(_3);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+2:1: +2:2
+        StorageDead(_2);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+2:1: +2:2
+        return;                          // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+2:2: +2:2
     }
 }
diff --git a/src/test/mir-opt/inline/issue_58867_inline_as_ref_as_mut.c.Inline.after.mir b/src/test/mir-opt/inline/issue_58867_inline_as_ref_as_mut.c.Inline.after.mir
index c7f20ff98ff7..ed4e9927ce9c 100644
--- a/src/test/mir-opt/inline/issue_58867_inline_as_ref_as_mut.c.Inline.after.mir
+++ b/src/test/mir-opt/inline/issue_58867_inline_as_ref_as_mut.c.Inline.after.mir
@@ -1,22 +1,22 @@
 // MIR for `c` after Inline
 
 fn c(_1: &[T]) -> &[T] {
-    debug x => _1;                       // in scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+0:13: +0:14
-    let mut _0: &[T];                    // return place in scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+0:25: +0:29
-    let _2: &[T];                        // in scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-    let mut _3: &[T];                    // in scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-    scope 1 (inlined <[T] as AsRef<[T]>>::as_ref) { // at $DIR/issue-58867-inline-as-ref-as-mut.rs:13:5: 13:15
+    debug x => _1;                       // in scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+0:13: +0:14
+    let mut _0: &[T];                    // return place in scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+0:25: +0:29
+    let _2: &[T];                        // in scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+    let mut _3: &[T];                    // in scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+    scope 1 (inlined <[T] as AsRef<[T]>>::as_ref) { // at $DIR/issue_58867_inline_as_ref_as_mut.rs:13:5: 13:15
         debug self => _3;                // in scope 1 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
     }
 
     bb0: {
-        StorageLive(_2);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-        StorageLive(_3);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-        _3 = &(*_1);                     // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
+        StorageLive(_2);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+        StorageLive(_3);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+        _3 = &(*_1);                     // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
         _2 = _3;                         // scope 1 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
-        _0 = &(*_2);                     // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-        StorageDead(_3);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:14: +1:15
-        StorageDead(_2);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+2:1: +2:2
-        return;                          // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+2:2: +2:2
+        _0 = &(*_2);                     // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+        StorageDead(_3);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:14: +1:15
+        StorageDead(_2);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+2:1: +2:2
+        return;                          // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+2:2: +2:2
     }
 }
diff --git a/src/test/mir-opt/inline/issue_58867_inline_as_ref_as_mut.d.Inline.after.mir b/src/test/mir-opt/inline/issue_58867_inline_as_ref_as_mut.d.Inline.after.mir
index d5f06c54a57c..18a2670be215 100644
--- a/src/test/mir-opt/inline/issue_58867_inline_as_ref_as_mut.d.Inline.after.mir
+++ b/src/test/mir-opt/inline/issue_58867_inline_as_ref_as_mut.d.Inline.after.mir
@@ -1,26 +1,26 @@
 // MIR for `d` after Inline
 
 fn d(_1: &Box<T>) -> &T {
-    debug x => _1;                       // in scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+0:13: +0:14
-    let mut _0: &T;                      // return place in scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+0:28: +0:30
-    let _2: &T;                          // in scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-    let mut _3: &std::boxed::Box<T>;     // in scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-    scope 1 (inlined <Box<T> as AsRef<T>>::as_ref) { // at $DIR/issue-58867-inline-as-ref-as-mut.rs:18:5: 18:15
+    debug x => _1;                       // in scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+0:13: +0:14
+    let mut _0: &T;                      // return place in scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+0:28: +0:30
+    let _2: &T;                          // in scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+    let mut _3: &std::boxed::Box<T>;     // in scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+    scope 1 (inlined <Box<T> as AsRef<T>>::as_ref) { // at $DIR/issue_58867_inline_as_ref_as_mut.rs:18:5: 18:15
         debug self => _3;                // in scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
         let mut _4: std::boxed::Box<T>;  // in scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
         let mut _5: *const T;            // in scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
     }
 
     bb0: {
-        StorageLive(_2);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-        StorageLive(_3);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-        _3 = &(*_1);                     // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
+        StorageLive(_2);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+        StorageLive(_3);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+        _3 = &(*_1);                     // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
         _4 = deref_copy (*_3);           // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
         _5 = (((_4.0: std::ptr::Unique<T>).0: std::ptr::NonNull<T>).0: *const T); // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
         _2 = &(*_5);                     // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
-        _0 = &(*_2);                     // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:5: +1:15
-        StorageDead(_3);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+1:14: +1:15
-        StorageDead(_2);                 // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+2:1: +2:2
-        return;                          // scope 0 at $DIR/issue-58867-inline-as-ref-as-mut.rs:+2:2: +2:2
+        _0 = &(*_2);                     // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
+        StorageDead(_3);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:14: +1:15
+        StorageDead(_2);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+2:1: +2:2
+        return;                          // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+2:2: +2:2
     }
 }
diff --git a/src/test/mir-opt/inline/issue-58867-inline-as-ref-as-mut.rs b/src/test/mir-opt/inline/issue_58867_inline_as_ref_as_mut.rs
similarity index 100%
rename from src/test/mir-opt/inline/issue-58867-inline-as-ref-as-mut.rs
rename to src/test/mir-opt/inline/issue_58867_inline_as_ref_as_mut.rs
diff --git a/src/test/mir-opt/inline/issue_76997_inline_scopes_parenting.main.Inline.after.mir b/src/test/mir-opt/inline/issue_76997_inline_scopes_parenting.main.Inline.after.mir
index fca53a72f882..d99ae1a6c7c8 100644
--- a/src/test/mir-opt/inline/issue_76997_inline_scopes_parenting.main.Inline.after.mir
+++ b/src/test/mir-opt/inline/issue_76997_inline_scopes_parenting.main.Inline.after.mir
@@ -1,42 +1,42 @@
 // MIR for `main` after Inline
 
 fn main() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/issue-76997-inline-scopes-parenting.rs:+0:11: +0:11
-    let _1: [closure@$DIR/issue-76997-inline-scopes-parenting.rs:5:13: 5:16]; // in scope 0 at $DIR/issue-76997-inline-scopes-parenting.rs:+1:9: +1:10
-    let mut _2: &[closure@$DIR/issue-76997-inline-scopes-parenting.rs:5:13: 5:16]; // in scope 0 at $DIR/issue-76997-inline-scopes-parenting.rs:+2:5: +2:6
-    let mut _3: ((),);                   // in scope 0 at $DIR/issue-76997-inline-scopes-parenting.rs:+2:5: +2:10
-    let mut _4: ();                      // in scope 0 at $DIR/issue-76997-inline-scopes-parenting.rs:+2:7: +2:9
-    let mut _5: ();                      // in scope 0 at $DIR/issue-76997-inline-scopes-parenting.rs:+2:5: +2:10
+    let mut _0: ();                      // return place in scope 0 at $DIR/issue_76997_inline_scopes_parenting.rs:+0:11: +0:11
+    let _1: [closure@$DIR/issue_76997_inline_scopes_parenting.rs:5:13: 5:16]; // in scope 0 at $DIR/issue_76997_inline_scopes_parenting.rs:+1:9: +1:10
+    let mut _2: &[closure@$DIR/issue_76997_inline_scopes_parenting.rs:5:13: 5:16]; // in scope 0 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:5: +2:6
+    let mut _3: ((),);                   // in scope 0 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:5: +2:10
+    let mut _4: ();                      // in scope 0 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:7: +2:9
+    let mut _5: ();                      // in scope 0 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:5: +2:10
     scope 1 {
-        debug f => _1;                   // in scope 1 at $DIR/issue-76997-inline-scopes-parenting.rs:+1:9: +1:10
-        scope 2 (inlined main::{closure#0}) { // at $DIR/issue-76997-inline-scopes-parenting.rs:6:5: 6:10
-            debug x => _5;               // in scope 2 at $DIR/issue-76997-inline-scopes-parenting.rs:+1:14: +1:15
-            let _6: ();                  // in scope 2 at $DIR/issue-76997-inline-scopes-parenting.rs:+1:23: +1:24
+        debug f => _1;                   // in scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+1:9: +1:10
+        scope 2 (inlined main::{closure#0}) { // at $DIR/issue_76997_inline_scopes_parenting.rs:6:5: 6:10
+            debug x => _5;               // in scope 2 at $DIR/issue_76997_inline_scopes_parenting.rs:+1:14: +1:15
+            let _6: ();                  // in scope 2 at $DIR/issue_76997_inline_scopes_parenting.rs:+1:23: +1:24
             scope 3 {
-                debug y => _6;           // in scope 3 at $DIR/issue-76997-inline-scopes-parenting.rs:+1:23: +1:24
+                debug y => _6;           // in scope 3 at $DIR/issue_76997_inline_scopes_parenting.rs:+1:23: +1:24
             }
         }
     }
 
     bb0: {
-        StorageLive(_1);                 // scope 0 at $DIR/issue-76997-inline-scopes-parenting.rs:+1:9: +1:10
-        Deinit(_1);                      // scope 0 at $DIR/issue-76997-inline-scopes-parenting.rs:+1:13: +1:33
-        StorageLive(_2);                 // scope 1 at $DIR/issue-76997-inline-scopes-parenting.rs:+2:5: +2:6
-        _2 = &_1;                        // scope 1 at $DIR/issue-76997-inline-scopes-parenting.rs:+2:5: +2:6
-        StorageLive(_3);                 // scope 1 at $DIR/issue-76997-inline-scopes-parenting.rs:+2:5: +2:10
-        StorageLive(_4);                 // scope 1 at $DIR/issue-76997-inline-scopes-parenting.rs:+2:7: +2:9
-        Deinit(_4);                      // scope 1 at $DIR/issue-76997-inline-scopes-parenting.rs:+2:7: +2:9
-        Deinit(_3);                      // scope 1 at $DIR/issue-76997-inline-scopes-parenting.rs:+2:5: +2:10
-        (_3.0: ()) = move _4;            // scope 1 at $DIR/issue-76997-inline-scopes-parenting.rs:+2:5: +2:10
-        StorageLive(_5);                 // scope 1 at $DIR/issue-76997-inline-scopes-parenting.rs:+2:5: +2:10
-        _5 = move (_3.0: ());            // scope 1 at $DIR/issue-76997-inline-scopes-parenting.rs:+2:5: +2:10
-        StorageLive(_6);                 // scope 2 at $DIR/issue-76997-inline-scopes-parenting.rs:+1:23: +1:24
-        StorageDead(_6);                 // scope 2 at $DIR/issue-76997-inline-scopes-parenting.rs:+1:32: +1:33
-        StorageDead(_5);                 // scope 1 at $DIR/issue-76997-inline-scopes-parenting.rs:+2:5: +2:10
-        StorageDead(_4);                 // scope 1 at $DIR/issue-76997-inline-scopes-parenting.rs:+2:9: +2:10
-        StorageDead(_3);                 // scope 1 at $DIR/issue-76997-inline-scopes-parenting.rs:+2:9: +2:10
-        StorageDead(_2);                 // scope 1 at $DIR/issue-76997-inline-scopes-parenting.rs:+2:9: +2:10
-        StorageDead(_1);                 // scope 0 at $DIR/issue-76997-inline-scopes-parenting.rs:+3:1: +3:2
-        return;                          // scope 0 at $DIR/issue-76997-inline-scopes-parenting.rs:+3:2: +3:2
+        StorageLive(_1);                 // scope 0 at $DIR/issue_76997_inline_scopes_parenting.rs:+1:9: +1:10
+        Deinit(_1);                      // scope 0 at $DIR/issue_76997_inline_scopes_parenting.rs:+1:13: +1:33
+        StorageLive(_2);                 // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:5: +2:6
+        _2 = &_1;                        // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:5: +2:6
+        StorageLive(_3);                 // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:5: +2:10
+        StorageLive(_4);                 // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:7: +2:9
+        Deinit(_4);                      // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:7: +2:9
+        Deinit(_3);                      // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:5: +2:10
+        (_3.0: ()) = move _4;            // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:5: +2:10
+        StorageLive(_5);                 // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:5: +2:10
+        _5 = move (_3.0: ());            // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:5: +2:10
+        StorageLive(_6);                 // scope 2 at $DIR/issue_76997_inline_scopes_parenting.rs:+1:23: +1:24
+        StorageDead(_6);                 // scope 2 at $DIR/issue_76997_inline_scopes_parenting.rs:+1:32: +1:33
+        StorageDead(_5);                 // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:5: +2:10
+        StorageDead(_4);                 // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:9: +2:10
+        StorageDead(_3);                 // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:9: +2:10
+        StorageDead(_2);                 // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:9: +2:10
+        StorageDead(_1);                 // scope 0 at $DIR/issue_76997_inline_scopes_parenting.rs:+3:1: +3:2
+        return;                          // scope 0 at $DIR/issue_76997_inline_scopes_parenting.rs:+3:2: +3:2
     }
 }
diff --git a/src/test/mir-opt/inline/issue-76997-inline-scopes-parenting.rs b/src/test/mir-opt/inline/issue_76997_inline_scopes_parenting.rs
similarity index 100%
rename from src/test/mir-opt/inline/issue-76997-inline-scopes-parenting.rs
rename to src/test/mir-opt/inline/issue_76997_inline_scopes_parenting.rs
diff --git a/src/test/mir-opt/inline/issue_78442.bar.Inline.diff b/src/test/mir-opt/inline/issue_78442.bar.Inline.diff
index 4186650dfabe..51a98465fd9a 100644
--- a/src/test/mir-opt/inline/issue_78442.bar.Inline.diff
+++ b/src/test/mir-opt/inline/issue_78442.bar.Inline.diff
@@ -2,67 +2,67 @@
 + // MIR for `bar` after Inline
   
   fn bar(_1: P) -> () {
-      debug _baz => _1;                    // in scope 0 at $DIR/issue-78442.rs:+2:5: +2:9
-      let mut _0: ();                      // return place in scope 0 at $DIR/issue-78442.rs:+3:3: +3:3
-      let _2: ();                          // in scope 0 at $DIR/issue-78442.rs:+4:5: +4:17
-      let mut _3: &fn() {foo};             // in scope 0 at $DIR/issue-78442.rs:+4:5: +4:15
-      let _4: fn() {foo};                  // in scope 0 at $DIR/issue-78442.rs:+4:5: +4:15
-      let mut _5: ();                      // in scope 0 at $DIR/issue-78442.rs:+4:5: +4:17
-+     scope 1 (inlined <fn() {foo} as Fn<()>>::call - shim(fn() {foo})) { // at $DIR/issue-78442.rs:11:5: 11:17
+      debug _baz => _1;                    // in scope 0 at $DIR/issue_78442.rs:+2:5: +2:9
+      let mut _0: ();                      // return place in scope 0 at $DIR/issue_78442.rs:+3:3: +3:3
+      let _2: ();                          // in scope 0 at $DIR/issue_78442.rs:+4:5: +4:17
+      let mut _3: &fn() {foo};             // in scope 0 at $DIR/issue_78442.rs:+4:5: +4:15
+      let _4: fn() {foo};                  // in scope 0 at $DIR/issue_78442.rs:+4:5: +4:15
+      let mut _5: ();                      // in scope 0 at $DIR/issue_78442.rs:+4:5: +4:17
++     scope 1 (inlined <fn() {foo} as Fn<()>>::call - shim(fn() {foo})) { // at $DIR/issue_78442.rs:11:5: 11:17
 +     }
   
       bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/issue-78442.rs:+4:5: +4:17
-          StorageLive(_3);                 // scope 0 at $DIR/issue-78442.rs:+4:5: +4:15
-          StorageLive(_4);                 // scope 0 at $DIR/issue-78442.rs:+4:5: +4:15
--         _4 = hide_foo() -> [return: bb1, unwind: bb4]; // scope 0 at $DIR/issue-78442.rs:+4:5: +4:15
-+         _4 = hide_foo() -> [return: bb1, unwind: bb3]; // scope 0 at $DIR/issue-78442.rs:+4:5: +4:15
+          StorageLive(_2);                 // scope 0 at $DIR/issue_78442.rs:+4:5: +4:17
+          StorageLive(_3);                 // scope 0 at $DIR/issue_78442.rs:+4:5: +4:15
+          StorageLive(_4);                 // scope 0 at $DIR/issue_78442.rs:+4:5: +4:15
+-         _4 = hide_foo() -> [return: bb1, unwind: bb4]; // scope 0 at $DIR/issue_78442.rs:+4:5: +4:15
++         _4 = hide_foo() -> [return: bb1, unwind: bb3]; // scope 0 at $DIR/issue_78442.rs:+4:5: +4:15
                                            // mir::Constant
-                                           // + span: $DIR/issue-78442.rs:11:5: 11:13
+                                           // + span: $DIR/issue_78442.rs:11:5: 11:13
                                            // + literal: Const { ty: fn() -> impl Fn() {hide_foo}, val: Value(<ZST>) }
       }
   
       bb1: {
-          _3 = &_4;                        // scope 0 at $DIR/issue-78442.rs:+4:5: +4:15
-          StorageLive(_5);                 // scope 0 at $DIR/issue-78442.rs:+4:5: +4:17
-          Deinit(_5);                      // scope 0 at $DIR/issue-78442.rs:+4:5: +4:17
--         _2 = <fn() {foo} as Fn<()>>::call(move _3, move _5) -> [return: bb2, unwind: bb4]; // scope 0 at $DIR/issue-78442.rs:+4:5: +4:17
+          _3 = &_4;                        // scope 0 at $DIR/issue_78442.rs:+4:5: +4:15
+          StorageLive(_5);                 // scope 0 at $DIR/issue_78442.rs:+4:5: +4:17
+          Deinit(_5);                      // scope 0 at $DIR/issue_78442.rs:+4:5: +4:17
+-         _2 = <fn() {foo} as Fn<()>>::call(move _3, move _5) -> [return: bb2, unwind: bb4]; // scope 0 at $DIR/issue_78442.rs:+4:5: +4:17
 -                                          // mir::Constant
--                                          // + span: $DIR/issue-78442.rs:11:5: 11:15
+-                                          // + span: $DIR/issue_78442.rs:11:5: 11:15
 -                                          // + literal: Const { ty: for<'a> extern "rust-call" fn(&'a fn() {foo}, ()) -> <fn() {foo} as FnOnce<()>>::Output {<fn() {foo} as Fn<()>>::call}, val: Value(<ZST>) }
 +         _2 = move (*_3)() -> [return: bb5, unwind: bb3]; // scope 1 at $SRC_DIR/core/src/ops/function.rs:LL:COL
       }
   
       bb2: {
--         StorageDead(_5);                 // scope 0 at $DIR/issue-78442.rs:+4:16: +4:17
--         StorageDead(_3);                 // scope 0 at $DIR/issue-78442.rs:+4:16: +4:17
--         StorageDead(_4);                 // scope 0 at $DIR/issue-78442.rs:+4:17: +4:18
--         StorageDead(_2);                 // scope 0 at $DIR/issue-78442.rs:+4:17: +4:18
--         _0 = const ();                   // scope 0 at $DIR/issue-78442.rs:+3:3: +5:2
--         drop(_1) -> [return: bb3, unwind: bb5]; // scope 0 at $DIR/issue-78442.rs:+5:1: +5:2
-+         return;                          // scope 0 at $DIR/issue-78442.rs:+5:2: +5:2
+-         StorageDead(_5);                 // scope 0 at $DIR/issue_78442.rs:+4:16: +4:17
+-         StorageDead(_3);                 // scope 0 at $DIR/issue_78442.rs:+4:16: +4:17
+-         StorageDead(_4);                 // scope 0 at $DIR/issue_78442.rs:+4:17: +4:18
+-         StorageDead(_2);                 // scope 0 at $DIR/issue_78442.rs:+4:17: +4:18
+-         _0 = const ();                   // scope 0 at $DIR/issue_78442.rs:+3:3: +5:2
+-         drop(_1) -> [return: bb3, unwind: bb5]; // scope 0 at $DIR/issue_78442.rs:+5:1: +5:2
++         return;                          // scope 0 at $DIR/issue_78442.rs:+5:2: +5:2
       }
   
 -     bb3: {
--         return;                          // scope 0 at $DIR/issue-78442.rs:+5:2: +5:2
+-         return;                          // scope 0 at $DIR/issue_78442.rs:+5:2: +5:2
 +     bb3 (cleanup): {
-+         drop(_1) -> bb4;                 // scope 0 at $DIR/issue-78442.rs:+5:1: +5:2
++         drop(_1) -> bb4;                 // scope 0 at $DIR/issue_78442.rs:+5:1: +5:2
       }
   
       bb4 (cleanup): {
--         drop(_1) -> bb5;                 // scope 0 at $DIR/issue-78442.rs:+5:1: +5:2
-+         resume;                          // scope 0 at $DIR/issue-78442.rs:+0:1: +5:2
+-         drop(_1) -> bb5;                 // scope 0 at $DIR/issue_78442.rs:+5:1: +5:2
++         resume;                          // scope 0 at $DIR/issue_78442.rs:+0:1: +5:2
       }
   
 -     bb5 (cleanup): {
--         resume;                          // scope 0 at $DIR/issue-78442.rs:+0:1: +5:2
+-         resume;                          // scope 0 at $DIR/issue_78442.rs:+0:1: +5:2
 +     bb5: {
-+         StorageDead(_5);                 // scope 0 at $DIR/issue-78442.rs:+4:16: +4:17
-+         StorageDead(_3);                 // scope 0 at $DIR/issue-78442.rs:+4:16: +4:17
-+         StorageDead(_4);                 // scope 0 at $DIR/issue-78442.rs:+4:17: +4:18
-+         StorageDead(_2);                 // scope 0 at $DIR/issue-78442.rs:+4:17: +4:18
-+         _0 = const ();                   // scope 0 at $DIR/issue-78442.rs:+3:3: +5:2
-+         drop(_1) -> [return: bb2, unwind: bb4]; // scope 0 at $DIR/issue-78442.rs:+5:1: +5:2
++         StorageDead(_5);                 // scope 0 at $DIR/issue_78442.rs:+4:16: +4:17
++         StorageDead(_3);                 // scope 0 at $DIR/issue_78442.rs:+4:16: +4:17
++         StorageDead(_4);                 // scope 0 at $DIR/issue_78442.rs:+4:17: +4:18
++         StorageDead(_2);                 // scope 0 at $DIR/issue_78442.rs:+4:17: +4:18
++         _0 = const ();                   // scope 0 at $DIR/issue_78442.rs:+3:3: +5:2
++         drop(_1) -> [return: bb2, unwind: bb4]; // scope 0 at $DIR/issue_78442.rs:+5:1: +5:2
       }
   }
   
diff --git a/src/test/mir-opt/inline/issue_78442.bar.RevealAll.diff b/src/test/mir-opt/inline/issue_78442.bar.RevealAll.diff
index 24e9a3df15ac..e47466c5e804 100644
--- a/src/test/mir-opt/inline/issue_78442.bar.RevealAll.diff
+++ b/src/test/mir-opt/inline/issue_78442.bar.RevealAll.diff
@@ -2,56 +2,56 @@
 + // MIR for `bar` after RevealAll
   
   fn bar(_1: P) -> () {
-      debug _baz => _1;                    // in scope 0 at $DIR/issue-78442.rs:+2:5: +2:9
-      let mut _0: ();                      // return place in scope 0 at $DIR/issue-78442.rs:+3:3: +3:3
-      let _2: ();                          // in scope 0 at $DIR/issue-78442.rs:+4:5: +4:17
--     let mut _3: &impl Fn();              // in scope 0 at $DIR/issue-78442.rs:+4:5: +4:15
--     let _4: impl Fn();                   // in scope 0 at $DIR/issue-78442.rs:+4:5: +4:15
-+     let mut _3: &fn() {foo};             // in scope 0 at $DIR/issue-78442.rs:+4:5: +4:15
-+     let _4: fn() {foo};                  // in scope 0 at $DIR/issue-78442.rs:+4:5: +4:15
-      let mut _5: ();                      // in scope 0 at $DIR/issue-78442.rs:+4:5: +4:17
+      debug _baz => _1;                    // in scope 0 at $DIR/issue_78442.rs:+2:5: +2:9
+      let mut _0: ();                      // return place in scope 0 at $DIR/issue_78442.rs:+3:3: +3:3
+      let _2: ();                          // in scope 0 at $DIR/issue_78442.rs:+4:5: +4:17
+-     let mut _3: &impl Fn();              // in scope 0 at $DIR/issue_78442.rs:+4:5: +4:15
+-     let _4: impl Fn();                   // in scope 0 at $DIR/issue_78442.rs:+4:5: +4:15
++     let mut _3: &fn() {foo};             // in scope 0 at $DIR/issue_78442.rs:+4:5: +4:15
++     let _4: fn() {foo};                  // in scope 0 at $DIR/issue_78442.rs:+4:5: +4:15
+      let mut _5: ();                      // in scope 0 at $DIR/issue_78442.rs:+4:5: +4:17
   
       bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/issue-78442.rs:+4:5: +4:17
-          StorageLive(_3);                 // scope 0 at $DIR/issue-78442.rs:+4:5: +4:15
-          StorageLive(_4);                 // scope 0 at $DIR/issue-78442.rs:+4:5: +4:15
-          _4 = hide_foo() -> [return: bb1, unwind: bb4]; // scope 0 at $DIR/issue-78442.rs:+4:5: +4:15
+          StorageLive(_2);                 // scope 0 at $DIR/issue_78442.rs:+4:5: +4:17
+          StorageLive(_3);                 // scope 0 at $DIR/issue_78442.rs:+4:5: +4:15
+          StorageLive(_4);                 // scope 0 at $DIR/issue_78442.rs:+4:5: +4:15
+          _4 = hide_foo() -> [return: bb1, unwind: bb4]; // scope 0 at $DIR/issue_78442.rs:+4:5: +4:15
                                            // mir::Constant
-                                           // + span: $DIR/issue-78442.rs:11:5: 11:13
+                                           // + span: $DIR/issue_78442.rs:11:5: 11:13
                                            // + literal: Const { ty: fn() -> impl Fn() {hide_foo}, val: Value(<ZST>) }
       }
   
       bb1: {
-          _3 = &_4;                        // scope 0 at $DIR/issue-78442.rs:+4:5: +4:15
-          StorageLive(_5);                 // scope 0 at $DIR/issue-78442.rs:+4:5: +4:17
-          Deinit(_5);                      // scope 0 at $DIR/issue-78442.rs:+4:5: +4:17
--         _2 = <impl Fn() as Fn<()>>::call(move _3, move _5) -> [return: bb2, unwind: bb4]; // scope 0 at $DIR/issue-78442.rs:+4:5: +4:17
-+         _2 = <fn() {foo} as Fn<()>>::call(move _3, move _5) -> [return: bb2, unwind: bb4]; // scope 0 at $DIR/issue-78442.rs:+4:5: +4:17
+          _3 = &_4;                        // scope 0 at $DIR/issue_78442.rs:+4:5: +4:15
+          StorageLive(_5);                 // scope 0 at $DIR/issue_78442.rs:+4:5: +4:17
+          Deinit(_5);                      // scope 0 at $DIR/issue_78442.rs:+4:5: +4:17
+-         _2 = <impl Fn() as Fn<()>>::call(move _3, move _5) -> [return: bb2, unwind: bb4]; // scope 0 at $DIR/issue_78442.rs:+4:5: +4:17
++         _2 = <fn() {foo} as Fn<()>>::call(move _3, move _5) -> [return: bb2, unwind: bb4]; // scope 0 at $DIR/issue_78442.rs:+4:5: +4:17
                                            // mir::Constant
-                                           // + span: $DIR/issue-78442.rs:11:5: 11:15
+                                           // + span: $DIR/issue_78442.rs:11:5: 11:15
 -                                          // + literal: Const { ty: for<'a> extern "rust-call" fn(&'a impl Fn(), ()) -> <impl Fn() as FnOnce<()>>::Output {<impl Fn() as Fn<()>>::call}, val: Value(<ZST>) }
 +                                          // + literal: Const { ty: for<'a> extern "rust-call" fn(&'a fn() {foo}, ()) -> <fn() {foo} as FnOnce<()>>::Output {<fn() {foo} as Fn<()>>::call}, val: Value(<ZST>) }
       }
   
       bb2: {
-          StorageDead(_5);                 // scope 0 at $DIR/issue-78442.rs:+4:16: +4:17
-          StorageDead(_3);                 // scope 0 at $DIR/issue-78442.rs:+4:16: +4:17
-          StorageDead(_4);                 // scope 0 at $DIR/issue-78442.rs:+4:17: +4:18
-          StorageDead(_2);                 // scope 0 at $DIR/issue-78442.rs:+4:17: +4:18
-          _0 = const ();                   // scope 0 at $DIR/issue-78442.rs:+3:3: +5:2
-          drop(_1) -> [return: bb3, unwind: bb5]; // scope 0 at $DIR/issue-78442.rs:+5:1: +5:2
+          StorageDead(_5);                 // scope 0 at $DIR/issue_78442.rs:+4:16: +4:17
+          StorageDead(_3);                 // scope 0 at $DIR/issue_78442.rs:+4:16: +4:17
+          StorageDead(_4);                 // scope 0 at $DIR/issue_78442.rs:+4:17: +4:18
+          StorageDead(_2);                 // scope 0 at $DIR/issue_78442.rs:+4:17: +4:18
+          _0 = const ();                   // scope 0 at $DIR/issue_78442.rs:+3:3: +5:2
+          drop(_1) -> [return: bb3, unwind: bb5]; // scope 0 at $DIR/issue_78442.rs:+5:1: +5:2
       }
   
       bb3: {
-          return;                          // scope 0 at $DIR/issue-78442.rs:+5:2: +5:2
+          return;                          // scope 0 at $DIR/issue_78442.rs:+5:2: +5:2
       }
   
       bb4 (cleanup): {
-          drop(_1) -> bb5;                 // scope 0 at $DIR/issue-78442.rs:+5:1: +5:2
+          drop(_1) -> bb5;                 // scope 0 at $DIR/issue_78442.rs:+5:1: +5:2
       }
   
       bb5 (cleanup): {
-          resume;                          // scope 0 at $DIR/issue-78442.rs:+0:1: +5:2
+          resume;                          // scope 0 at $DIR/issue_78442.rs:+0:1: +5:2
       }
   }
   
diff --git a/src/test/mir-opt/inline/issue-78442.rs b/src/test/mir-opt/inline/issue_78442.rs
similarity index 100%
rename from src/test/mir-opt/inline/issue-78442.rs
rename to src/test/mir-opt/inline/issue_78442.rs
diff --git a/src/test/mir-opt/inline/polymorphic-recursion.rs b/src/test/mir-opt/inline/polymorphic_recursion.rs
similarity index 100%
rename from src/test/mir-opt/inline/polymorphic-recursion.rs
rename to src/test/mir-opt/inline/polymorphic_recursion.rs
diff --git a/src/test/mir-opt/issue_101973.inner.ConstProp.diff b/src/test/mir-opt/issue_101973.inner.ConstProp.diff
index 281afe4be17e..bce40f277d23 100644
--- a/src/test/mir-opt/issue_101973.inner.ConstProp.diff
+++ b/src/test/mir-opt/issue_101973.inner.ConstProp.diff
@@ -2,29 +2,29 @@
 + // MIR for `inner` after ConstProp
   
   fn inner(_1: u32) -> i64 {
-      debug fields => _1;                  // in scope 0 at $DIR/issue-101973.rs:+0:14: +0:20
-      let mut _0: i64;                     // return place in scope 0 at $DIR/issue-101973.rs:+0:30: +0:33
-      let mut _2: i32;                     // in scope 0 at $DIR/issue-101973.rs:+1:5: +1:65
-      let mut _3: u32;                     // in scope 0 at $DIR/issue-101973.rs:+1:5: +1:58
-      let mut _4: u32;                     // in scope 0 at $DIR/issue-101973.rs:+1:5: +1:17
-      let mut _5: u32;                     // in scope 0 at $DIR/issue-101973.rs:+1:10: +1:16
-      let mut _6: u32;                     // in scope 0 at $DIR/issue-101973.rs:+1:31: +1:57
-      let mut _7: u32;                     // in scope 0 at $DIR/issue-101973.rs:+1:31: +1:52
-      let mut _8: u32;                     // in scope 0 at $DIR/issue-101973.rs:+1:32: +1:45
-      let mut _9: u32;                     // in scope 0 at $DIR/issue-101973.rs:+1:33: +1:39
-      let mut _10: (u32, bool);            // in scope 0 at $DIR/issue-101973.rs:+1:32: +1:45
-      let mut _11: (u32, bool);            // in scope 0 at $DIR/issue-101973.rs:+1:31: +1:57
-      scope 1 (inlined imm8) {             // at $DIR/issue-101973.rs:14:5: 14:17
-          debug x => _5;                   // in scope 1 at $DIR/issue-101973.rs:5:13: 5:14
-          let mut _12: u32;                // in scope 1 at $DIR/issue-101973.rs:7:12: 7:27
-          let mut _13: u32;                // in scope 1 at $DIR/issue-101973.rs:7:12: 7:20
-          let mut _14: u32;                // in scope 1 at $DIR/issue-101973.rs:7:13: 7:14
-          let mut _15: (u32, bool);        // in scope 1 at $DIR/issue-101973.rs:7:12: 7:20
+      debug fields => _1;                  // in scope 0 at $DIR/issue_101973.rs:+0:14: +0:20
+      let mut _0: i64;                     // return place in scope 0 at $DIR/issue_101973.rs:+0:30: +0:33
+      let mut _2: i32;                     // in scope 0 at $DIR/issue_101973.rs:+1:5: +1:65
+      let mut _3: u32;                     // in scope 0 at $DIR/issue_101973.rs:+1:5: +1:58
+      let mut _4: u32;                     // in scope 0 at $DIR/issue_101973.rs:+1:5: +1:17
+      let mut _5: u32;                     // in scope 0 at $DIR/issue_101973.rs:+1:10: +1:16
+      let mut _6: u32;                     // in scope 0 at $DIR/issue_101973.rs:+1:31: +1:57
+      let mut _7: u32;                     // in scope 0 at $DIR/issue_101973.rs:+1:31: +1:52
+      let mut _8: u32;                     // in scope 0 at $DIR/issue_101973.rs:+1:32: +1:45
+      let mut _9: u32;                     // in scope 0 at $DIR/issue_101973.rs:+1:33: +1:39
+      let mut _10: (u32, bool);            // in scope 0 at $DIR/issue_101973.rs:+1:32: +1:45
+      let mut _11: (u32, bool);            // in scope 0 at $DIR/issue_101973.rs:+1:31: +1:57
+      scope 1 (inlined imm8) {             // at $DIR/issue_101973.rs:14:5: 14:17
+          debug x => _5;                   // in scope 1 at $DIR/issue_101973.rs:5:13: 5:14
+          let mut _12: u32;                // in scope 1 at $DIR/issue_101973.rs:7:12: 7:27
+          let mut _13: u32;                // in scope 1 at $DIR/issue_101973.rs:7:12: 7:20
+          let mut _14: u32;                // in scope 1 at $DIR/issue_101973.rs:7:13: 7:14
+          let mut _15: (u32, bool);        // in scope 1 at $DIR/issue_101973.rs:7:12: 7:20
           scope 2 {
-              debug out => _4;             // in scope 2 at $DIR/issue-101973.rs:6:9: 6:16
+              debug out => _4;             // in scope 2 at $DIR/issue_101973.rs:6:9: 6:16
           }
       }
-      scope 3 (inlined core::num::<impl u32>::rotate_right) { // at $DIR/issue-101973.rs:14:5: 14:58
+      scope 3 (inlined core::num::<impl u32>::rotate_right) { // at $DIR/issue_101973.rs:14:5: 14:58
           debug self => _4;                // in scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
           debug n => _6;                   // in scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
           let mut _16: u32;                // in scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
@@ -32,32 +32,31 @@
       }
   
       bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/issue-101973.rs:+1:5: +1:65
-          StorageLive(_3);                 // scope 0 at $DIR/issue-101973.rs:+1:5: +1:58
-          StorageLive(_4);                 // scope 0 at $DIR/issue-101973.rs:+1:5: +1:17
-          StorageLive(_5);                 // scope 0 at $DIR/issue-101973.rs:+1:10: +1:16
-          _5 = _1;                         // scope 0 at $DIR/issue-101973.rs:+1:10: +1:16
-          _4 = const 0_u32;                // scope 1 at $DIR/issue-101973.rs:6:19: 6:23
-          StorageLive(_12);                // scope 2 at $DIR/issue-101973.rs:7:12: 7:27
-          StorageLive(_13);                // scope 2 at $DIR/issue-101973.rs:7:12: 7:20
-          StorageLive(_14);                // scope 2 at $DIR/issue-101973.rs:7:13: 7:14
-          _14 = _5;                        // scope 2 at $DIR/issue-101973.rs:7:13: 7:14
-          _15 = CheckedShr(_14, const 0_i32); // scope 2 at $DIR/issue-101973.rs:7:12: 7:20
-          assert(!move (_15.1: bool), "attempt to shift right by `{}`, which would overflow", const 0_i32) -> bb3; // scope 2 at $DIR/issue-101973.rs:7:12: 7:20
+          StorageLive(_2);                 // scope 0 at $DIR/issue_101973.rs:+1:5: +1:65
+          StorageLive(_3);                 // scope 0 at $DIR/issue_101973.rs:+1:5: +1:58
+          StorageLive(_4);                 // scope 0 at $DIR/issue_101973.rs:+1:5: +1:17
+          StorageLive(_5);                 // scope 0 at $DIR/issue_101973.rs:+1:10: +1:16
+          _5 = _1;                         // scope 0 at $DIR/issue_101973.rs:+1:10: +1:16
+          StorageLive(_12);                // scope 2 at $DIR/issue_101973.rs:7:12: 7:27
+          StorageLive(_13);                // scope 2 at $DIR/issue_101973.rs:7:12: 7:20
+          StorageLive(_14);                // scope 2 at $DIR/issue_101973.rs:7:13: 7:14
+          _14 = _5;                        // scope 2 at $DIR/issue_101973.rs:7:13: 7:14
+          _15 = CheckedShr(_14, const 0_i32); // scope 2 at $DIR/issue_101973.rs:7:12: 7:20
+          assert(!move (_15.1: bool), "attempt to shift right by `{}`, which would overflow", const 0_i32) -> bb3; // scope 2 at $DIR/issue_101973.rs:7:12: 7:20
       }
   
       bb1: {
-          _8 = move (_10.0: u32);          // scope 0 at $DIR/issue-101973.rs:+1:32: +1:45
-          StorageDead(_9);                 // scope 0 at $DIR/issue-101973.rs:+1:44: +1:45
-          _7 = BitAnd(move _8, const 15_u32); // scope 0 at $DIR/issue-101973.rs:+1:31: +1:52
-          StorageDead(_8);                 // scope 0 at $DIR/issue-101973.rs:+1:51: +1:52
-          _11 = CheckedShl(_7, const 1_i32); // scope 0 at $DIR/issue-101973.rs:+1:31: +1:57
-          assert(!move (_11.1: bool), "attempt to shift left by `{}`, which would overflow", const 1_i32) -> bb2; // scope 0 at $DIR/issue-101973.rs:+1:31: +1:57
+          _8 = move (_10.0: u32);          // scope 0 at $DIR/issue_101973.rs:+1:32: +1:45
+          StorageDead(_9);                 // scope 0 at $DIR/issue_101973.rs:+1:44: +1:45
+          _7 = BitAnd(move _8, const 15_u32); // scope 0 at $DIR/issue_101973.rs:+1:31: +1:52
+          StorageDead(_8);                 // scope 0 at $DIR/issue_101973.rs:+1:51: +1:52
+          _11 = CheckedShl(_7, const 1_i32); // scope 0 at $DIR/issue_101973.rs:+1:31: +1:57
+          assert(!move (_11.1: bool), "attempt to shift left by `{}`, which would overflow", const 1_i32) -> bb2; // scope 0 at $DIR/issue_101973.rs:+1:31: +1:57
       }
   
       bb2: {
-          _6 = move (_11.0: u32);          // scope 0 at $DIR/issue-101973.rs:+1:31: +1:57
-          StorageDead(_7);                 // scope 0 at $DIR/issue-101973.rs:+1:56: +1:57
+          _6 = move (_11.0: u32);          // scope 0 at $DIR/issue_101973.rs:+1:31: +1:57
+          StorageDead(_7);                 // scope 0 at $DIR/issue_101973.rs:+1:56: +1:57
           StorageLive(_16);                // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
           _16 = _4;                        // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
           StorageLive(_17);                // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
@@ -69,32 +68,32 @@
       }
   
       bb3: {
-          _13 = move (_15.0: u32);         // scope 2 at $DIR/issue-101973.rs:7:12: 7:20
-          StorageDead(_14);                // scope 2 at $DIR/issue-101973.rs:7:19: 7:20
-          _12 = BitAnd(move _13, const 255_u32); // scope 2 at $DIR/issue-101973.rs:7:12: 7:27
-          StorageDead(_13);                // scope 2 at $DIR/issue-101973.rs:7:26: 7:27
-          _4 = BitOr(_4, move _12);        // scope 2 at $DIR/issue-101973.rs:7:5: 7:27
-          StorageDead(_12);                // scope 2 at $DIR/issue-101973.rs:7:26: 7:27
-          StorageDead(_5);                 // scope 0 at $DIR/issue-101973.rs:+1:16: +1:17
-          StorageLive(_6);                 // scope 0 at $DIR/issue-101973.rs:+1:31: +1:57
-          StorageLive(_7);                 // scope 0 at $DIR/issue-101973.rs:+1:31: +1:52
-          StorageLive(_8);                 // scope 0 at $DIR/issue-101973.rs:+1:32: +1:45
-          StorageLive(_9);                 // scope 0 at $DIR/issue-101973.rs:+1:33: +1:39
-          _9 = _1;                         // scope 0 at $DIR/issue-101973.rs:+1:33: +1:39
-          _10 = CheckedShr(_9, const 8_i32); // scope 0 at $DIR/issue-101973.rs:+1:32: +1:45
-          assert(!move (_10.1: bool), "attempt to shift right by `{}`, which would overflow", const 8_i32) -> bb1; // scope 0 at $DIR/issue-101973.rs:+1:32: +1:45
+          _13 = move (_15.0: u32);         // scope 2 at $DIR/issue_101973.rs:7:12: 7:20
+          StorageDead(_14);                // scope 2 at $DIR/issue_101973.rs:7:19: 7:20
+          _12 = BitAnd(move _13, const 255_u32); // scope 2 at $DIR/issue_101973.rs:7:12: 7:27
+          StorageDead(_13);                // scope 2 at $DIR/issue_101973.rs:7:26: 7:27
+          _4 = BitOr(const 0_u32, move _12); // scope 2 at $DIR/issue_101973.rs:7:5: 7:27
+          StorageDead(_12);                // scope 2 at $DIR/issue_101973.rs:7:26: 7:27
+          StorageDead(_5);                 // scope 0 at $DIR/issue_101973.rs:+1:16: +1:17
+          StorageLive(_6);                 // scope 0 at $DIR/issue_101973.rs:+1:31: +1:57
+          StorageLive(_7);                 // scope 0 at $DIR/issue_101973.rs:+1:31: +1:52
+          StorageLive(_8);                 // scope 0 at $DIR/issue_101973.rs:+1:32: +1:45
+          StorageLive(_9);                 // scope 0 at $DIR/issue_101973.rs:+1:33: +1:39
+          _9 = _1;                         // scope 0 at $DIR/issue_101973.rs:+1:33: +1:39
+          _10 = CheckedShr(_9, const 8_i32); // scope 0 at $DIR/issue_101973.rs:+1:32: +1:45
+          assert(!move (_10.1: bool), "attempt to shift right by `{}`, which would overflow", const 8_i32) -> bb1; // scope 0 at $DIR/issue_101973.rs:+1:32: +1:45
       }
   
       bb4: {
           StorageDead(_17);                // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
           StorageDead(_16);                // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
-          StorageDead(_6);                 // scope 0 at $DIR/issue-101973.rs:+1:57: +1:58
-          StorageDead(_4);                 // scope 0 at $DIR/issue-101973.rs:+1:57: +1:58
-          _2 = move _3 as i32 (IntToInt);  // scope 0 at $DIR/issue-101973.rs:+1:5: +1:65
-          StorageDead(_3);                 // scope 0 at $DIR/issue-101973.rs:+1:64: +1:65
-          _0 = move _2 as i64 (IntToInt);  // scope 0 at $DIR/issue-101973.rs:+1:5: +1:72
-          StorageDead(_2);                 // scope 0 at $DIR/issue-101973.rs:+1:71: +1:72
-          return;                          // scope 0 at $DIR/issue-101973.rs:+2:2: +2:2
+          StorageDead(_6);                 // scope 0 at $DIR/issue_101973.rs:+1:57: +1:58
+          StorageDead(_4);                 // scope 0 at $DIR/issue_101973.rs:+1:57: +1:58
+          _2 = move _3 as i32 (IntToInt);  // scope 0 at $DIR/issue_101973.rs:+1:5: +1:65
+          StorageDead(_3);                 // scope 0 at $DIR/issue_101973.rs:+1:64: +1:65
+          _0 = move _2 as i64 (IntToInt);  // scope 0 at $DIR/issue_101973.rs:+1:5: +1:72
+          StorageDead(_2);                 // scope 0 at $DIR/issue_101973.rs:+1:71: +1:72
+          return;                          // scope 0 at $DIR/issue_101973.rs:+2:2: +2:2
       }
   }
   
diff --git a/src/test/mir-opt/issue-101973.rs b/src/test/mir-opt/issue_101973.rs
similarity index 100%
rename from src/test/mir-opt/issue-101973.rs
rename to src/test/mir-opt/issue_101973.rs
diff --git a/src/test/mir-opt/issue_38669.main.SimplifyCfg-initial.after.mir b/src/test/mir-opt/issue_38669.main.SimplifyCfg-initial.after.mir
index b13987f7360e..82210081832c 100644
--- a/src/test/mir-opt/issue_38669.main.SimplifyCfg-initial.after.mir
+++ b/src/test/mir-opt/issue_38669.main.SimplifyCfg-initial.after.mir
@@ -1,52 +1,52 @@
 // MIR for `main` after SimplifyCfg-initial
 
 fn main() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/issue-38669.rs:+0:11: +0:11
-    let mut _1: bool;                    // in scope 0 at $DIR/issue-38669.rs:+1:9: +1:25
-    let mut _2: ();                      // in scope 0 at $DIR/issue-38669.rs:+0:1: +8:2
-    let _3: ();                          // in scope 0 at $DIR/issue-38669.rs:+3:9: +5:10
-    let mut _4: bool;                    // in scope 0 at $DIR/issue-38669.rs:+3:12: +3:24
-    let mut _5: !;                       // in scope 0 at $DIR/issue-38669.rs:+3:25: +5:10
+    let mut _0: ();                      // return place in scope 0 at $DIR/issue_38669.rs:+0:11: +0:11
+    let mut _1: bool;                    // in scope 0 at $DIR/issue_38669.rs:+1:9: +1:25
+    let mut _2: ();                      // in scope 0 at $DIR/issue_38669.rs:+0:1: +8:2
+    let _3: ();                          // in scope 0 at $DIR/issue_38669.rs:+3:9: +5:10
+    let mut _4: bool;                    // in scope 0 at $DIR/issue_38669.rs:+3:12: +3:24
+    let mut _5: !;                       // in scope 0 at $DIR/issue_38669.rs:+3:25: +5:10
     scope 1 {
-        debug should_break => _1;        // in scope 1 at $DIR/issue-38669.rs:+1:9: +1:25
+        debug should_break => _1;        // in scope 1 at $DIR/issue_38669.rs:+1:9: +1:25
     }
 
     bb0: {
-        StorageLive(_1);                 // scope 0 at $DIR/issue-38669.rs:+1:9: +1:25
-        _1 = const false;                // scope 0 at $DIR/issue-38669.rs:+1:28: +1:33
-        FakeRead(ForLet(None), _1);      // scope 0 at $DIR/issue-38669.rs:+1:9: +1:25
-        goto -> bb1;                     // scope 1 at $DIR/issue-38669.rs:+2:5: +7:6
+        StorageLive(_1);                 // scope 0 at $DIR/issue_38669.rs:+1:9: +1:25
+        _1 = const false;                // scope 0 at $DIR/issue_38669.rs:+1:28: +1:33
+        FakeRead(ForLet(None), _1);      // scope 0 at $DIR/issue_38669.rs:+1:9: +1:25
+        goto -> bb1;                     // scope 1 at $DIR/issue_38669.rs:+2:5: +7:6
     }
 
     bb1: {
-        falseUnwind -> [real: bb2, cleanup: bb5]; // scope 1 at $DIR/issue-38669.rs:+2:5: +7:6
+        falseUnwind -> [real: bb2, cleanup: bb5]; // scope 1 at $DIR/issue_38669.rs:+2:5: +7:6
     }
 
     bb2: {
-        StorageLive(_3);                 // scope 1 at $DIR/issue-38669.rs:+3:9: +5:10
-        StorageLive(_4);                 // scope 1 at $DIR/issue-38669.rs:+3:12: +3:24
-        _4 = _1;                         // scope 1 at $DIR/issue-38669.rs:+3:12: +3:24
-        switchInt(move _4) -> [false: bb4, otherwise: bb3]; // scope 1 at $DIR/issue-38669.rs:+3:12: +3:24
+        StorageLive(_3);                 // scope 1 at $DIR/issue_38669.rs:+3:9: +5:10
+        StorageLive(_4);                 // scope 1 at $DIR/issue_38669.rs:+3:12: +3:24
+        _4 = _1;                         // scope 1 at $DIR/issue_38669.rs:+3:12: +3:24
+        switchInt(move _4) -> [false: bb4, otherwise: bb3]; // scope 1 at $DIR/issue_38669.rs:+3:12: +3:24
     }
 
     bb3: {
-        _0 = const ();                   // scope 1 at $DIR/issue-38669.rs:+4:13: +4:18
-        StorageDead(_4);                 // scope 1 at $DIR/issue-38669.rs:+5:9: +5:10
-        StorageDead(_3);                 // scope 1 at $DIR/issue-38669.rs:+5:9: +5:10
-        StorageDead(_1);                 // scope 0 at $DIR/issue-38669.rs:+8:1: +8:2
-        return;                          // scope 0 at $DIR/issue-38669.rs:+8:2: +8:2
+        _0 = const ();                   // scope 1 at $DIR/issue_38669.rs:+4:13: +4:18
+        StorageDead(_4);                 // scope 1 at $DIR/issue_38669.rs:+5:9: +5:10
+        StorageDead(_3);                 // scope 1 at $DIR/issue_38669.rs:+5:9: +5:10
+        StorageDead(_1);                 // scope 0 at $DIR/issue_38669.rs:+8:1: +8:2
+        return;                          // scope 0 at $DIR/issue_38669.rs:+8:2: +8:2
     }
 
     bb4: {
-        _3 = const ();                   // scope 1 at $DIR/issue-38669.rs:+5:10: +5:10
-        StorageDead(_4);                 // scope 1 at $DIR/issue-38669.rs:+5:9: +5:10
-        StorageDead(_3);                 // scope 1 at $DIR/issue-38669.rs:+5:9: +5:10
-        _1 = const true;                 // scope 1 at $DIR/issue-38669.rs:+6:9: +6:28
-        _2 = const ();                   // scope 1 at $DIR/issue-38669.rs:+2:10: +7:6
-        goto -> bb1;                     // scope 1 at $DIR/issue-38669.rs:+2:5: +7:6
+        _3 = const ();                   // scope 1 at $DIR/issue_38669.rs:+5:10: +5:10
+        StorageDead(_4);                 // scope 1 at $DIR/issue_38669.rs:+5:9: +5:10
+        StorageDead(_3);                 // scope 1 at $DIR/issue_38669.rs:+5:9: +5:10
+        _1 = const true;                 // scope 1 at $DIR/issue_38669.rs:+6:9: +6:28
+        _2 = const ();                   // scope 1 at $DIR/issue_38669.rs:+2:10: +7:6
+        goto -> bb1;                     // scope 1 at $DIR/issue_38669.rs:+2:5: +7:6
     }
 
     bb5 (cleanup): {
-        resume;                          // scope 0 at $DIR/issue-38669.rs:+0:1: +8:2
+        resume;                          // scope 0 at $DIR/issue_38669.rs:+0:1: +8:2
     }
 }
diff --git a/src/test/mir-opt/issue-38669.rs b/src/test/mir-opt/issue_38669.rs
similarity index 100%
rename from src/test/mir-opt/issue-38669.rs
rename to src/test/mir-opt/issue_38669.rs
diff --git a/src/test/mir-opt/issue_41110.main.ElaborateDrops.after.mir b/src/test/mir-opt/issue_41110.main.ElaborateDrops.after.mir
index 1d7cb91d6a7e..c573ad5a8e4a 100644
--- a/src/test/mir-opt/issue_41110.main.ElaborateDrops.after.mir
+++ b/src/test/mir-opt/issue_41110.main.ElaborateDrops.after.mir
@@ -1,70 +1,70 @@
 // MIR for `main` after ElaborateDrops
 
 fn main() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/issue-41110.rs:+0:11: +0:11
-    let _1: ();                          // in scope 0 at $DIR/issue-41110.rs:+1:9: +1:10
-    let mut _2: S;                       // in scope 0 at $DIR/issue-41110.rs:+1:13: +1:14
-    let mut _3: S;                       // in scope 0 at $DIR/issue-41110.rs:+1:21: +1:27
-    let mut _4: S;                       // in scope 0 at $DIR/issue-41110.rs:+1:21: +1:22
-    let mut _5: bool;                    // in scope 0 at $DIR/issue-41110.rs:+1:27: +1:28
+    let mut _0: ();                      // return place in scope 0 at $DIR/issue_41110.rs:+0:11: +0:11
+    let _1: ();                          // in scope 0 at $DIR/issue_41110.rs:+1:9: +1:10
+    let mut _2: S;                       // in scope 0 at $DIR/issue_41110.rs:+1:13: +1:14
+    let mut _3: S;                       // in scope 0 at $DIR/issue_41110.rs:+1:21: +1:27
+    let mut _4: S;                       // in scope 0 at $DIR/issue_41110.rs:+1:21: +1:22
+    let mut _5: bool;                    // in scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
     scope 1 {
-        debug x => _1;                   // in scope 1 at $DIR/issue-41110.rs:+1:9: +1:10
+        debug x => _1;                   // in scope 1 at $DIR/issue_41110.rs:+1:9: +1:10
     }
 
     bb0: {
-        _5 = const false;                // scope 0 at $DIR/issue-41110.rs:+1:9: +1:10
-        StorageLive(_1);                 // scope 0 at $DIR/issue-41110.rs:+1:9: +1:10
-        StorageLive(_2);                 // scope 0 at $DIR/issue-41110.rs:+1:13: +1:14
-        _5 = const true;                 // scope 0 at $DIR/issue-41110.rs:+1:13: +1:14
-        _2 = S;                          // scope 0 at $DIR/issue-41110.rs:+1:13: +1:14
-        StorageLive(_3);                 // scope 0 at $DIR/issue-41110.rs:+1:21: +1:27
-        StorageLive(_4);                 // scope 0 at $DIR/issue-41110.rs:+1:21: +1:22
-        _4 = S;                          // scope 0 at $DIR/issue-41110.rs:+1:21: +1:22
-        _3 = S::id(move _4) -> [return: bb1, unwind: bb4]; // scope 0 at $DIR/issue-41110.rs:+1:21: +1:27
+        _5 = const false;                // scope 0 at $DIR/issue_41110.rs:+1:9: +1:10
+        StorageLive(_1);                 // scope 0 at $DIR/issue_41110.rs:+1:9: +1:10
+        StorageLive(_2);                 // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14
+        _5 = const true;                 // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14
+        _2 = S;                          // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14
+        StorageLive(_3);                 // scope 0 at $DIR/issue_41110.rs:+1:21: +1:27
+        StorageLive(_4);                 // scope 0 at $DIR/issue_41110.rs:+1:21: +1:22
+        _4 = S;                          // scope 0 at $DIR/issue_41110.rs:+1:21: +1:22
+        _3 = S::id(move _4) -> [return: bb1, unwind: bb4]; // scope 0 at $DIR/issue_41110.rs:+1:21: +1:27
                                          // mir::Constant
-                                         // + span: $DIR/issue-41110.rs:8:23: 8:25
+                                         // + span: $DIR/issue_41110.rs:8:23: 8:25
                                          // + literal: Const { ty: fn(S) -> S {S::id}, val: Value(<ZST>) }
     }
 
     bb1: {
-        StorageDead(_4);                 // scope 0 at $DIR/issue-41110.rs:+1:26: +1:27
-        _5 = const false;                // scope 0 at $DIR/issue-41110.rs:+1:13: +1:28
-        _1 = S::other(move _2, move _3) -> [return: bb2, unwind: bb3]; // scope 0 at $DIR/issue-41110.rs:+1:13: +1:28
+        StorageDead(_4);                 // scope 0 at $DIR/issue_41110.rs:+1:26: +1:27
+        _5 = const false;                // scope 0 at $DIR/issue_41110.rs:+1:13: +1:28
+        _1 = S::other(move _2, move _3) -> [return: bb2, unwind: bb3]; // scope 0 at $DIR/issue_41110.rs:+1:13: +1:28
                                          // mir::Constant
-                                         // + span: $DIR/issue-41110.rs:8:15: 8:20
+                                         // + span: $DIR/issue_41110.rs:8:15: 8:20
                                          // + literal: Const { ty: fn(S, S) {S::other}, val: Value(<ZST>) }
     }
 
     bb2: {
-        StorageDead(_3);                 // scope 0 at $DIR/issue-41110.rs:+1:27: +1:28
-        _5 = const false;                // scope 0 at $DIR/issue-41110.rs:+1:27: +1:28
-        StorageDead(_2);                 // scope 0 at $DIR/issue-41110.rs:+1:27: +1:28
-        _0 = const ();                   // scope 0 at $DIR/issue-41110.rs:+0:11: +2:2
-        StorageDead(_1);                 // scope 0 at $DIR/issue-41110.rs:+2:1: +2:2
-        return;                          // scope 0 at $DIR/issue-41110.rs:+2:2: +2:2
+        StorageDead(_3);                 // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
+        _5 = const false;                // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
+        StorageDead(_2);                 // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
+        _0 = const ();                   // scope 0 at $DIR/issue_41110.rs:+0:11: +2:2
+        StorageDead(_1);                 // scope 0 at $DIR/issue_41110.rs:+2:1: +2:2
+        return;                          // scope 0 at $DIR/issue_41110.rs:+2:2: +2:2
     }
 
     bb3 (cleanup): {
-        goto -> bb5;                     // scope 0 at $DIR/issue-41110.rs:+1:27: +1:28
+        goto -> bb5;                     // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
     }
 
     bb4 (cleanup): {
-        goto -> bb5;                     // scope 0 at $DIR/issue-41110.rs:+1:26: +1:27
+        goto -> bb5;                     // scope 0 at $DIR/issue_41110.rs:+1:26: +1:27
     }
 
     bb5 (cleanup): {
-        goto -> bb8;                     // scope 0 at $DIR/issue-41110.rs:+1:27: +1:28
+        goto -> bb8;                     // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
     }
 
     bb6 (cleanup): {
-        resume;                          // scope 0 at $DIR/issue-41110.rs:+0:1: +2:2
+        resume;                          // scope 0 at $DIR/issue_41110.rs:+0:1: +2:2
     }
 
     bb7 (cleanup): {
-        drop(_2) -> bb6;                 // scope 0 at $DIR/issue-41110.rs:+1:27: +1:28
+        drop(_2) -> bb6;                 // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
     }
 
     bb8 (cleanup): {
-        switchInt(_5) -> [false: bb6, otherwise: bb7]; // scope 0 at $DIR/issue-41110.rs:+1:27: +1:28
+        switchInt(_5) -> [false: bb6, otherwise: bb7]; // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
     }
 }
diff --git a/src/test/mir-opt/issue-41110.rs b/src/test/mir-opt/issue_41110.rs
similarity index 100%
rename from src/test/mir-opt/issue-41110.rs
rename to src/test/mir-opt/issue_41110.rs
diff --git a/src/test/mir-opt/issue_41110.test.ElaborateDrops.after.mir b/src/test/mir-opt/issue_41110.test.ElaborateDrops.after.mir
index b0e3496b2c8e..470b03232818 100644
--- a/src/test/mir-opt/issue_41110.test.ElaborateDrops.after.mir
+++ b/src/test/mir-opt/issue_41110.test.ElaborateDrops.after.mir
@@ -1,101 +1,101 @@
 // MIR for `test` after ElaborateDrops
 
 fn test() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/issue-41110.rs:+0:15: +0:15
-    let _1: S;                           // in scope 0 at $DIR/issue-41110.rs:+1:9: +1:10
-    let _3: ();                          // in scope 0 at $DIR/issue-41110.rs:+3:5: +3:12
-    let mut _4: S;                       // in scope 0 at $DIR/issue-41110.rs:+3:10: +3:11
-    let mut _5: S;                       // in scope 0 at $DIR/issue-41110.rs:+4:9: +4:10
-    let mut _6: bool;                    // in scope 0 at $DIR/issue-41110.rs:+5:1: +5:2
+    let mut _0: ();                      // return place in scope 0 at $DIR/issue_41110.rs:+0:15: +0:15
+    let _1: S;                           // in scope 0 at $DIR/issue_41110.rs:+1:9: +1:10
+    let _3: ();                          // in scope 0 at $DIR/issue_41110.rs:+3:5: +3:12
+    let mut _4: S;                       // in scope 0 at $DIR/issue_41110.rs:+3:10: +3:11
+    let mut _5: S;                       // in scope 0 at $DIR/issue_41110.rs:+4:9: +4:10
+    let mut _6: bool;                    // in scope 0 at $DIR/issue_41110.rs:+5:1: +5:2
     scope 1 {
-        debug u => _1;                   // in scope 1 at $DIR/issue-41110.rs:+1:9: +1:10
-        let mut _2: S;                   // in scope 1 at $DIR/issue-41110.rs:+2:9: +2:14
+        debug u => _1;                   // in scope 1 at $DIR/issue_41110.rs:+1:9: +1:10
+        let mut _2: S;                   // in scope 1 at $DIR/issue_41110.rs:+2:9: +2:14
         scope 2 {
-            debug v => _2;               // in scope 2 at $DIR/issue-41110.rs:+2:9: +2:14
+            debug v => _2;               // in scope 2 at $DIR/issue_41110.rs:+2:9: +2:14
         }
     }
 
     bb0: {
-        _6 = const false;                // scope 0 at $DIR/issue-41110.rs:+1:9: +1:10
-        StorageLive(_1);                 // scope 0 at $DIR/issue-41110.rs:+1:9: +1:10
-        _6 = const true;                 // scope 0 at $DIR/issue-41110.rs:+1:13: +1:14
-        _1 = S;                          // scope 0 at $DIR/issue-41110.rs:+1:13: +1:14
-        StorageLive(_2);                 // scope 1 at $DIR/issue-41110.rs:+2:9: +2:14
-        _2 = S;                          // scope 1 at $DIR/issue-41110.rs:+2:17: +2:18
-        StorageLive(_3);                 // scope 2 at $DIR/issue-41110.rs:+3:5: +3:12
-        StorageLive(_4);                 // scope 2 at $DIR/issue-41110.rs:+3:10: +3:11
-        _4 = move _2;                    // scope 2 at $DIR/issue-41110.rs:+3:10: +3:11
-        _3 = std::mem::drop::<S>(move _4) -> [return: bb1, unwind: bb7]; // scope 2 at $DIR/issue-41110.rs:+3:5: +3:12
+        _6 = const false;                // scope 0 at $DIR/issue_41110.rs:+1:9: +1:10
+        StorageLive(_1);                 // scope 0 at $DIR/issue_41110.rs:+1:9: +1:10
+        _6 = const true;                 // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14
+        _1 = S;                          // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14
+        StorageLive(_2);                 // scope 1 at $DIR/issue_41110.rs:+2:9: +2:14
+        _2 = S;                          // scope 1 at $DIR/issue_41110.rs:+2:17: +2:18
+        StorageLive(_3);                 // scope 2 at $DIR/issue_41110.rs:+3:5: +3:12
+        StorageLive(_4);                 // scope 2 at $DIR/issue_41110.rs:+3:10: +3:11
+        _4 = move _2;                    // scope 2 at $DIR/issue_41110.rs:+3:10: +3:11
+        _3 = std::mem::drop::<S>(move _4) -> [return: bb1, unwind: bb7]; // scope 2 at $DIR/issue_41110.rs:+3:5: +3:12
                                          // mir::Constant
-                                         // + span: $DIR/issue-41110.rs:17:5: 17:9
+                                         // + span: $DIR/issue_41110.rs:17:5: 17:9
                                          // + literal: Const { ty: fn(S) {std::mem::drop::<S>}, val: Value(<ZST>) }
     }
 
     bb1: {
-        StorageDead(_4);                 // scope 2 at $DIR/issue-41110.rs:+3:11: +3:12
-        StorageDead(_3);                 // scope 2 at $DIR/issue-41110.rs:+3:12: +3:13
-        StorageLive(_5);                 // scope 2 at $DIR/issue-41110.rs:+4:9: +4:10
-        _6 = const false;                // scope 2 at $DIR/issue-41110.rs:+4:9: +4:10
-        _5 = move _1;                    // scope 2 at $DIR/issue-41110.rs:+4:9: +4:10
-        goto -> bb12;                    // scope 2 at $DIR/issue-41110.rs:+4:5: +4:6
+        StorageDead(_4);                 // scope 2 at $DIR/issue_41110.rs:+3:11: +3:12
+        StorageDead(_3);                 // scope 2 at $DIR/issue_41110.rs:+3:12: +3:13
+        StorageLive(_5);                 // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10
+        _6 = const false;                // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10
+        _5 = move _1;                    // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10
+        goto -> bb12;                    // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6
     }
 
     bb2: {
-        goto -> bb3;                     // scope 2 at $DIR/issue-41110.rs:+4:9: +4:10
+        goto -> bb3;                     // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10
     }
 
     bb3: {
-        StorageDead(_5);                 // scope 2 at $DIR/issue-41110.rs:+4:9: +4:10
-        _0 = const ();                   // scope 0 at $DIR/issue-41110.rs:+0:15: +5:2
-        drop(_2) -> [return: bb4, unwind: bb9]; // scope 1 at $DIR/issue-41110.rs:+5:1: +5:2
+        StorageDead(_5);                 // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10
+        _0 = const ();                   // scope 0 at $DIR/issue_41110.rs:+0:15: +5:2
+        drop(_2) -> [return: bb4, unwind: bb9]; // scope 1 at $DIR/issue_41110.rs:+5:1: +5:2
     }
 
     bb4: {
-        StorageDead(_2);                 // scope 1 at $DIR/issue-41110.rs:+5:1: +5:2
-        goto -> bb5;                     // scope 0 at $DIR/issue-41110.rs:+5:1: +5:2
+        StorageDead(_2);                 // scope 1 at $DIR/issue_41110.rs:+5:1: +5:2
+        goto -> bb5;                     // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2
     }
 
     bb5: {
-        _6 = const false;                // scope 0 at $DIR/issue-41110.rs:+5:1: +5:2
-        StorageDead(_1);                 // scope 0 at $DIR/issue-41110.rs:+5:1: +5:2
-        return;                          // scope 0 at $DIR/issue-41110.rs:+5:2: +5:2
+        _6 = const false;                // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2
+        StorageDead(_1);                 // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2
+        return;                          // scope 0 at $DIR/issue_41110.rs:+5:2: +5:2
     }
 
     bb6 (cleanup): {
-        goto -> bb8;                     // scope 2 at $DIR/issue-41110.rs:+4:9: +4:10
+        goto -> bb8;                     // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10
     }
 
     bb7 (cleanup): {
-        goto -> bb8;                     // scope 2 at $DIR/issue-41110.rs:+3:11: +3:12
+        goto -> bb8;                     // scope 2 at $DIR/issue_41110.rs:+3:11: +3:12
     }
 
     bb8 (cleanup): {
-        goto -> bb9;                     // scope 1 at $DIR/issue-41110.rs:+5:1: +5:2
+        goto -> bb9;                     // scope 1 at $DIR/issue_41110.rs:+5:1: +5:2
     }
 
     bb9 (cleanup): {
-        goto -> bb14;                    // scope 0 at $DIR/issue-41110.rs:+5:1: +5:2
+        goto -> bb14;                    // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2
     }
 
     bb10 (cleanup): {
-        resume;                          // scope 0 at $DIR/issue-41110.rs:+0:1: +5:2
+        resume;                          // scope 0 at $DIR/issue_41110.rs:+0:1: +5:2
     }
 
     bb11 (cleanup): {
-        _2 = move _5;                    // scope 2 at $DIR/issue-41110.rs:+4:5: +4:6
-        goto -> bb6;                     // scope 2 at $DIR/issue-41110.rs:+4:5: +4:6
+        _2 = move _5;                    // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6
+        goto -> bb6;                     // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6
     }
 
     bb12: {
-        _2 = move _5;                    // scope 2 at $DIR/issue-41110.rs:+4:5: +4:6
-        goto -> bb2;                     // scope 2 at $DIR/issue-41110.rs:+4:5: +4:6
+        _2 = move _5;                    // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6
+        goto -> bb2;                     // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6
     }
 
     bb13 (cleanup): {
-        drop(_1) -> bb10;                // scope 0 at $DIR/issue-41110.rs:+5:1: +5:2
+        drop(_1) -> bb10;                // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2
     }
 
     bb14 (cleanup): {
-        switchInt(_6) -> [false: bb10, otherwise: bb13]; // scope 0 at $DIR/issue-41110.rs:+5:1: +5:2
+        switchInt(_6) -> [false: bb10, otherwise: bb13]; // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2
     }
 }
diff --git a/src/test/mir-opt/issue-41697.rs b/src/test/mir-opt/issue_41697.rs
similarity index 100%
rename from src/test/mir-opt/issue-41697.rs
rename to src/test/mir-opt/issue_41697.rs
diff --git a/src/test/mir-opt/issue_41697.{impl#0}-{constant#0}.SimplifyCfg-promote-consts.after.mir b/src/test/mir-opt/issue_41697.{impl#0}-{constant#0}.SimplifyCfg-promote-consts.after.mir
index 047b24db4664..8af087d84f11 100644
--- a/src/test/mir-opt/issue_41697.{impl#0}-{constant#0}.SimplifyCfg-promote-consts.after.mir
+++ b/src/test/mir-opt/issue_41697.{impl#0}-{constant#0}.SimplifyCfg-promote-consts.after.mir
@@ -1,20 +1,20 @@
-// MIR for `<impl at $DIR/issue-41697.rs:18:1: 18:23>::{constant#0}` after SimplifyCfg-promote-consts
+// MIR for `<impl at $DIR/issue_41697.rs:18:1: 18:23>::{constant#0}` after SimplifyCfg-promote-consts
 
-<impl at $DIR/issue-41697.rs:18:1: 18:23>::{constant#0}: usize = {
-    let mut _0: usize;                   // return place in scope 0 at $DIR/issue-41697.rs:+0:19: +0:22
-    let mut _1: (usize, bool);           // in scope 0 at $DIR/issue-41697.rs:+0:19: +0:22
+<impl at $DIR/issue_41697.rs:18:1: 18:23>::{constant#0}: usize = {
+    let mut _0: usize;                   // return place in scope 0 at $DIR/issue_41697.rs:+0:19: +0:22
+    let mut _1: (usize, bool);           // in scope 0 at $DIR/issue_41697.rs:+0:19: +0:22
 
     bb0: {
-        _1 = CheckedAdd(const 1_usize, const 1_usize); // scope 0 at $DIR/issue-41697.rs:+0:19: +0:22
-        assert(!move (_1.1: bool), "attempt to compute `{} + {}`, which would overflow", const 1_usize, const 1_usize) -> [success: bb1, unwind: bb2]; // scope 0 at $DIR/issue-41697.rs:+0:19: +0:22
+        _1 = CheckedAdd(const 1_usize, const 1_usize); // scope 0 at $DIR/issue_41697.rs:+0:19: +0:22
+        assert(!move (_1.1: bool), "attempt to compute `{} + {}`, which would overflow", const 1_usize, const 1_usize) -> [success: bb1, unwind: bb2]; // scope 0 at $DIR/issue_41697.rs:+0:19: +0:22
     }
 
     bb1: {
-        _0 = move (_1.0: usize);         // scope 0 at $DIR/issue-41697.rs:+0:19: +0:22
-        return;                          // scope 0 at $DIR/issue-41697.rs:+0:19: +0:22
+        _0 = move (_1.0: usize);         // scope 0 at $DIR/issue_41697.rs:+0:19: +0:22
+        return;                          // scope 0 at $DIR/issue_41697.rs:+0:19: +0:22
     }
 
     bb2 (cleanup): {
-        resume;                          // scope 0 at $DIR/issue-41697.rs:+0:19: +0:22
+        resume;                          // scope 0 at $DIR/issue_41697.rs:+0:19: +0:22
     }
 }
diff --git a/src/test/mir-opt/issue_41888.main.ElaborateDrops.after.mir b/src/test/mir-opt/issue_41888.main.ElaborateDrops.after.mir
index f95a0a1c013b..73372c97bea7 100644
--- a/src/test/mir-opt/issue_41888.main.ElaborateDrops.after.mir
+++ b/src/test/mir-opt/issue_41888.main.ElaborateDrops.after.mir
@@ -1,152 +1,152 @@
 // MIR for `main` after ElaborateDrops
 
 fn main() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/issue-41888.rs:+0:11: +0:11
-    let _1: E;                           // in scope 0 at $DIR/issue-41888.rs:+1:9: +1:10
-    let mut _2: bool;                    // in scope 0 at $DIR/issue-41888.rs:+2:8: +2:14
-    let mut _3: E;                       // in scope 0 at $DIR/issue-41888.rs:+3:13: +3:20
-    let mut _4: K;                       // in scope 0 at $DIR/issue-41888.rs:+3:18: +3:19
-    let mut _5: isize;                   // in scope 0 at $DIR/issue-41888.rs:+4:16: +4:24
-    let mut _7: bool;                    // in scope 0 at $DIR/issue-41888.rs:+9:1: +9:2
-    let mut _8: bool;                    // in scope 0 at $DIR/issue-41888.rs:+9:1: +9:2
-    let mut _9: bool;                    // in scope 0 at $DIR/issue-41888.rs:+9:1: +9:2
-    let mut _10: isize;                  // in scope 0 at $DIR/issue-41888.rs:+9:1: +9:2
-    let mut _11: isize;                  // in scope 0 at $DIR/issue-41888.rs:+9:1: +9:2
+    let mut _0: ();                      // return place in scope 0 at $DIR/issue_41888.rs:+0:11: +0:11
+    let _1: E;                           // in scope 0 at $DIR/issue_41888.rs:+1:9: +1:10
+    let mut _2: bool;                    // in scope 0 at $DIR/issue_41888.rs:+2:8: +2:14
+    let mut _3: E;                       // in scope 0 at $DIR/issue_41888.rs:+3:13: +3:20
+    let mut _4: K;                       // in scope 0 at $DIR/issue_41888.rs:+3:18: +3:19
+    let mut _5: isize;                   // in scope 0 at $DIR/issue_41888.rs:+4:16: +4:24
+    let mut _7: bool;                    // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
+    let mut _8: bool;                    // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
+    let mut _9: bool;                    // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
+    let mut _10: isize;                  // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
+    let mut _11: isize;                  // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
     scope 1 {
-        debug e => _1;                   // in scope 1 at $DIR/issue-41888.rs:+1:9: +1:10
+        debug e => _1;                   // in scope 1 at $DIR/issue_41888.rs:+1:9: +1:10
         scope 2 {
-            debug _k => _6;              // in scope 2 at $DIR/issue-41888.rs:+4:21: +4:23
-            let _6: K;                   // in scope 2 at $DIR/issue-41888.rs:+4:21: +4:23
+            debug _k => _6;              // in scope 2 at $DIR/issue_41888.rs:+4:21: +4:23
+            let _6: K;                   // in scope 2 at $DIR/issue_41888.rs:+4:21: +4:23
         }
     }
 
     bb0: {
-        _9 = const false;                // scope 0 at $DIR/issue-41888.rs:+1:9: +1:10
-        _7 = const false;                // scope 0 at $DIR/issue-41888.rs:+1:9: +1:10
-        _8 = const false;                // scope 0 at $DIR/issue-41888.rs:+1:9: +1:10
-        StorageLive(_1);                 // scope 0 at $DIR/issue-41888.rs:+1:9: +1:10
-        StorageLive(_2);                 // scope 1 at $DIR/issue-41888.rs:+2:8: +2:14
-        _2 = cond() -> [return: bb1, unwind: bb11]; // scope 1 at $DIR/issue-41888.rs:+2:8: +2:14
+        _9 = const false;                // scope 0 at $DIR/issue_41888.rs:+1:9: +1:10
+        _7 = const false;                // scope 0 at $DIR/issue_41888.rs:+1:9: +1:10
+        _8 = const false;                // scope 0 at $DIR/issue_41888.rs:+1:9: +1:10
+        StorageLive(_1);                 // scope 0 at $DIR/issue_41888.rs:+1:9: +1:10
+        StorageLive(_2);                 // scope 1 at $DIR/issue_41888.rs:+2:8: +2:14
+        _2 = cond() -> [return: bb1, unwind: bb11]; // scope 1 at $DIR/issue_41888.rs:+2:8: +2:14
                                          // mir::Constant
-                                         // + span: $DIR/issue-41888.rs:8:8: 8:12
+                                         // + span: $DIR/issue_41888.rs:8:8: 8:12
                                          // + literal: Const { ty: fn() -> bool {cond}, val: Value(<ZST>) }
     }
 
     bb1: {
-        switchInt(move _2) -> [false: bb7, otherwise: bb2]; // scope 1 at $DIR/issue-41888.rs:+2:8: +2:14
+        switchInt(move _2) -> [false: bb7, otherwise: bb2]; // scope 1 at $DIR/issue_41888.rs:+2:8: +2:14
     }
 
     bb2: {
-        StorageLive(_3);                 // scope 1 at $DIR/issue-41888.rs:+3:13: +3:20
-        StorageLive(_4);                 // scope 1 at $DIR/issue-41888.rs:+3:18: +3:19
-        _4 = K;                          // scope 1 at $DIR/issue-41888.rs:+3:18: +3:19
-        _3 = E::F(move _4);              // scope 1 at $DIR/issue-41888.rs:+3:13: +3:20
-        StorageDead(_4);                 // scope 1 at $DIR/issue-41888.rs:+3:19: +3:20
-        goto -> bb14;                    // scope 1 at $DIR/issue-41888.rs:+3:9: +3:10
+        StorageLive(_3);                 // scope 1 at $DIR/issue_41888.rs:+3:13: +3:20
+        StorageLive(_4);                 // scope 1 at $DIR/issue_41888.rs:+3:18: +3:19
+        _4 = K;                          // scope 1 at $DIR/issue_41888.rs:+3:18: +3:19
+        _3 = E::F(move _4);              // scope 1 at $DIR/issue_41888.rs:+3:13: +3:20
+        StorageDead(_4);                 // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20
+        goto -> bb14;                    // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
     }
 
     bb3: {
-        goto -> bb4;                     // scope 1 at $DIR/issue-41888.rs:+3:19: +3:20
+        goto -> bb4;                     // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20
     }
 
     bb4: {
-        StorageDead(_3);                 // scope 1 at $DIR/issue-41888.rs:+3:19: +3:20
-        _5 = discriminant(_1);           // scope 2 at $DIR/issue-41888.rs:+4:16: +4:24
-        switchInt(move _5) -> [0_isize: bb5, otherwise: bb6]; // scope 2 at $DIR/issue-41888.rs:+4:16: +4:24
+        StorageDead(_3);                 // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20
+        _5 = discriminant(_1);           // scope 2 at $DIR/issue_41888.rs:+4:16: +4:24
+        switchInt(move _5) -> [0_isize: bb5, otherwise: bb6]; // scope 2 at $DIR/issue_41888.rs:+4:16: +4:24
     }
 
     bb5: {
-        StorageLive(_6);                 // scope 2 at $DIR/issue-41888.rs:+4:21: +4:23
-        _9 = const false;                // scope 2 at $DIR/issue-41888.rs:+4:21: +4:23
-        _6 = move ((_1 as F).0: K);      // scope 2 at $DIR/issue-41888.rs:+4:21: +4:23
-        _0 = const ();                   // scope 2 at $DIR/issue-41888.rs:+4:29: +7:10
-        StorageDead(_6);                 // scope 1 at $DIR/issue-41888.rs:+7:9: +7:10
-        goto -> bb8;                     // scope 1 at $DIR/issue-41888.rs:+4:9: +7:10
+        StorageLive(_6);                 // scope 2 at $DIR/issue_41888.rs:+4:21: +4:23
+        _9 = const false;                // scope 2 at $DIR/issue_41888.rs:+4:21: +4:23
+        _6 = move ((_1 as F).0: K);      // scope 2 at $DIR/issue_41888.rs:+4:21: +4:23
+        _0 = const ();                   // scope 2 at $DIR/issue_41888.rs:+4:29: +7:10
+        StorageDead(_6);                 // scope 1 at $DIR/issue_41888.rs:+7:9: +7:10
+        goto -> bb8;                     // scope 1 at $DIR/issue_41888.rs:+4:9: +7:10
     }
 
     bb6: {
-        _0 = const ();                   // scope 1 at $DIR/issue-41888.rs:+7:10: +7:10
-        goto -> bb8;                     // scope 1 at $DIR/issue-41888.rs:+4:9: +7:10
+        _0 = const ();                   // scope 1 at $DIR/issue_41888.rs:+7:10: +7:10
+        goto -> bb8;                     // scope 1 at $DIR/issue_41888.rs:+4:9: +7:10
     }
 
     bb7: {
-        _0 = const ();                   // scope 1 at $DIR/issue-41888.rs:+8:6: +8:6
-        goto -> bb8;                     // scope 1 at $DIR/issue-41888.rs:+2:5: +8:6
+        _0 = const ();                   // scope 1 at $DIR/issue_41888.rs:+8:6: +8:6
+        goto -> bb8;                     // scope 1 at $DIR/issue_41888.rs:+2:5: +8:6
     }
 
     bb8: {
-        StorageDead(_2);                 // scope 1 at $DIR/issue-41888.rs:+8:5: +8:6
-        goto -> bb20;                    // scope 0 at $DIR/issue-41888.rs:+9:1: +9:2
+        StorageDead(_2);                 // scope 1 at $DIR/issue_41888.rs:+8:5: +8:6
+        goto -> bb20;                    // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
     }
 
     bb9: {
-        _7 = const false;                // scope 0 at $DIR/issue-41888.rs:+9:1: +9:2
-        _8 = const false;                // scope 0 at $DIR/issue-41888.rs:+9:1: +9:2
-        _9 = const false;                // scope 0 at $DIR/issue-41888.rs:+9:1: +9:2
-        StorageDead(_1);                 // scope 0 at $DIR/issue-41888.rs:+9:1: +9:2
-        return;                          // scope 0 at $DIR/issue-41888.rs:+9:2: +9:2
+        _7 = const false;                // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
+        _8 = const false;                // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
+        _9 = const false;                // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
+        StorageDead(_1);                 // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
+        return;                          // scope 0 at $DIR/issue_41888.rs:+9:2: +9:2
     }
 
     bb10 (cleanup): {
-        goto -> bb11;                    // scope 1 at $DIR/issue-41888.rs:+3:19: +3:20
+        goto -> bb11;                    // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20
     }
 
     bb11 (cleanup): {
-        goto -> bb12;                    // scope 0 at $DIR/issue-41888.rs:+9:1: +9:2
+        goto -> bb12;                    // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
     }
 
     bb12 (cleanup): {
-        resume;                          // scope 0 at $DIR/issue-41888.rs:+0:1: +9:2
+        resume;                          // scope 0 at $DIR/issue_41888.rs:+0:1: +9:2
     }
 
     bb13 (cleanup): {
-        _7 = const true;                 // scope 1 at $DIR/issue-41888.rs:+3:9: +3:10
-        _8 = const true;                 // scope 1 at $DIR/issue-41888.rs:+3:9: +3:10
-        _9 = const true;                 // scope 1 at $DIR/issue-41888.rs:+3:9: +3:10
-        _1 = move _3;                    // scope 1 at $DIR/issue-41888.rs:+3:9: +3:10
-        goto -> bb10;                    // scope 1 at $DIR/issue-41888.rs:+3:9: +3:10
+        _7 = const true;                 // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
+        _8 = const true;                 // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
+        _9 = const true;                 // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
+        _1 = move _3;                    // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
+        goto -> bb10;                    // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
     }
 
     bb14: {
-        _7 = const true;                 // scope 1 at $DIR/issue-41888.rs:+3:9: +3:10
-        _8 = const true;                 // scope 1 at $DIR/issue-41888.rs:+3:9: +3:10
-        _9 = const true;                 // scope 1 at $DIR/issue-41888.rs:+3:9: +3:10
-        _1 = move _3;                    // scope 1 at $DIR/issue-41888.rs:+3:9: +3:10
-        goto -> bb3;                     // scope 1 at $DIR/issue-41888.rs:+3:9: +3:10
+        _7 = const true;                 // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
+        _8 = const true;                 // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
+        _9 = const true;                 // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
+        _1 = move _3;                    // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
+        goto -> bb3;                     // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
     }
 
     bb15: {
-        _7 = const false;                // scope 0 at $DIR/issue-41888.rs:+9:1: +9:2
-        goto -> bb9;                     // scope 0 at $DIR/issue-41888.rs:+9:1: +9:2
+        _7 = const false;                // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
+        goto -> bb9;                     // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
     }
 
     bb16 (cleanup): {
-        goto -> bb12;                    // scope 0 at $DIR/issue-41888.rs:+9:1: +9:2
+        goto -> bb12;                    // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
     }
 
     bb17: {
-        drop(_1) -> [return: bb15, unwind: bb12]; // scope 0 at $DIR/issue-41888.rs:+9:1: +9:2
+        drop(_1) -> [return: bb15, unwind: bb12]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
     }
 
     bb18 (cleanup): {
-        drop(_1) -> bb12;                // scope 0 at $DIR/issue-41888.rs:+9:1: +9:2
+        drop(_1) -> bb12;                // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
     }
 
     bb19: {
-        _10 = discriminant(_1);          // scope 0 at $DIR/issue-41888.rs:+9:1: +9:2
-        switchInt(move _10) -> [0_isize: bb15, otherwise: bb17]; // scope 0 at $DIR/issue-41888.rs:+9:1: +9:2
+        _10 = discriminant(_1);          // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
+        switchInt(move _10) -> [0_isize: bb15, otherwise: bb17]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
     }
 
     bb20: {
-        switchInt(_7) -> [false: bb15, otherwise: bb19]; // scope 0 at $DIR/issue-41888.rs:+9:1: +9:2
+        switchInt(_7) -> [false: bb15, otherwise: bb19]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
     }
 
     bb21 (cleanup): {
-        _11 = discriminant(_1);          // scope 0 at $DIR/issue-41888.rs:+9:1: +9:2
-        switchInt(move _11) -> [0_isize: bb16, otherwise: bb18]; // scope 0 at $DIR/issue-41888.rs:+9:1: +9:2
+        _11 = discriminant(_1);          // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
+        switchInt(move _11) -> [0_isize: bb16, otherwise: bb18]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
     }
 
     bb22 (cleanup): {
-        switchInt(_7) -> [false: bb12, otherwise: bb21]; // scope 0 at $DIR/issue-41888.rs:+9:1: +9:2
+        switchInt(_7) -> [false: bb12, otherwise: bb21]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
     }
 }
diff --git a/src/test/mir-opt/issue-41888.rs b/src/test/mir-opt/issue_41888.rs
similarity index 100%
rename from src/test/mir-opt/issue-41888.rs
rename to src/test/mir-opt/issue_41888.rs
diff --git a/src/test/mir-opt/issue-62289.rs b/src/test/mir-opt/issue_62289.rs
similarity index 100%
rename from src/test/mir-opt/issue-62289.rs
rename to src/test/mir-opt/issue_62289.rs
diff --git a/src/test/mir-opt/issue_62289.test.ElaborateDrops.before.mir b/src/test/mir-opt/issue_62289.test.ElaborateDrops.before.mir
index 72603dc5dbea..6969a66ac192 100644
--- a/src/test/mir-opt/issue_62289.test.ElaborateDrops.before.mir
+++ b/src/test/mir-opt/issue_62289.test.ElaborateDrops.before.mir
@@ -1,122 +1,122 @@
 // MIR for `test` before ElaborateDrops
 
 fn test() -> Option<Box<u32>> {
-    let mut _0: std::option::Option<std::boxed::Box<u32>>; // return place in scope 0 at $DIR/issue-62289.rs:+0:14: +0:30
-    let mut _1: std::boxed::Box<u32>;    // in scope 0 at $DIR/issue-62289.rs:+1:10: +1:21
-    let mut _2: usize;                   // in scope 0 at $DIR/issue-62289.rs:+1:10: +1:21
-    let mut _3: usize;                   // in scope 0 at $DIR/issue-62289.rs:+1:10: +1:21
-    let mut _4: *mut u8;                 // in scope 0 at $DIR/issue-62289.rs:+1:10: +1:21
-    let mut _5: std::boxed::Box<u32>;    // in scope 0 at $DIR/issue-62289.rs:+1:10: +1:21
-    let mut _6: std::ops::ControlFlow<std::option::Option<std::convert::Infallible>, u32>; // in scope 0 at $DIR/issue-62289.rs:+1:15: +1:20
-    let mut _7: std::option::Option<u32>; // in scope 0 at $DIR/issue-62289.rs:+1:15: +1:19
-    let mut _8: isize;                   // in scope 0 at $DIR/issue-62289.rs:+1:19: +1:20
-    let _9: std::option::Option<std::convert::Infallible>; // in scope 0 at $DIR/issue-62289.rs:+1:19: +1:20
-    let mut _10: !;                      // in scope 0 at $DIR/issue-62289.rs:+1:19: +1:20
-    let mut _11: std::option::Option<std::convert::Infallible>; // in scope 0 at $DIR/issue-62289.rs:+1:19: +1:20
-    let _12: u32;                        // in scope 0 at $DIR/issue-62289.rs:+1:15: +1:20
+    let mut _0: std::option::Option<std::boxed::Box<u32>>; // return place in scope 0 at $DIR/issue_62289.rs:+0:14: +0:30
+    let mut _1: std::boxed::Box<u32>;    // in scope 0 at $DIR/issue_62289.rs:+1:10: +1:21
+    let mut _2: usize;                   // in scope 0 at $DIR/issue_62289.rs:+1:10: +1:21
+    let mut _3: usize;                   // in scope 0 at $DIR/issue_62289.rs:+1:10: +1:21
+    let mut _4: *mut u8;                 // in scope 0 at $DIR/issue_62289.rs:+1:10: +1:21
+    let mut _5: std::boxed::Box<u32>;    // in scope 0 at $DIR/issue_62289.rs:+1:10: +1:21
+    let mut _6: std::ops::ControlFlow<std::option::Option<std::convert::Infallible>, u32>; // in scope 0 at $DIR/issue_62289.rs:+1:15: +1:20
+    let mut _7: std::option::Option<u32>; // in scope 0 at $DIR/issue_62289.rs:+1:15: +1:19
+    let mut _8: isize;                   // in scope 0 at $DIR/issue_62289.rs:+1:19: +1:20
+    let _9: std::option::Option<std::convert::Infallible>; // in scope 0 at $DIR/issue_62289.rs:+1:19: +1:20
+    let mut _10: !;                      // in scope 0 at $DIR/issue_62289.rs:+1:19: +1:20
+    let mut _11: std::option::Option<std::convert::Infallible>; // in scope 0 at $DIR/issue_62289.rs:+1:19: +1:20
+    let _12: u32;                        // in scope 0 at $DIR/issue_62289.rs:+1:15: +1:20
     scope 1 {
     }
     scope 2 {
-        debug residual => _9;            // in scope 2 at $DIR/issue-62289.rs:+1:19: +1:20
+        debug residual => _9;            // in scope 2 at $DIR/issue_62289.rs:+1:19: +1:20
         scope 3 {
         }
     }
     scope 4 {
-        debug val => _12;                // in scope 4 at $DIR/issue-62289.rs:+1:15: +1:20
+        debug val => _12;                // in scope 4 at $DIR/issue_62289.rs:+1:15: +1:20
         scope 5 {
         }
     }
 
     bb0: {
-        StorageLive(_1);                 // scope 0 at $DIR/issue-62289.rs:+1:10: +1:21
-        _2 = SizeOf(u32);                // scope 1 at $DIR/issue-62289.rs:+1:10: +1:21
-        _3 = AlignOf(u32);               // scope 1 at $DIR/issue-62289.rs:+1:10: +1:21
-        _4 = alloc::alloc::exchange_malloc(move _2, move _3) -> bb1; // scope 1 at $DIR/issue-62289.rs:+1:10: +1:21
+        StorageLive(_1);                 // scope 0 at $DIR/issue_62289.rs:+1:10: +1:21
+        _2 = SizeOf(u32);                // scope 1 at $DIR/issue_62289.rs:+1:10: +1:21
+        _3 = AlignOf(u32);               // scope 1 at $DIR/issue_62289.rs:+1:10: +1:21
+        _4 = alloc::alloc::exchange_malloc(move _2, move _3) -> bb1; // scope 1 at $DIR/issue_62289.rs:+1:10: +1:21
                                          // mir::Constant
-                                         // + span: $DIR/issue-62289.rs:9:10: 9:21
+                                         // + span: $DIR/issue_62289.rs:9:10: 9:21
                                          // + literal: Const { ty: unsafe fn(usize, usize) -> *mut u8 {alloc::alloc::exchange_malloc}, val: Value(<ZST>) }
     }
 
     bb1: {
-        StorageLive(_5);                 // scope 0 at $DIR/issue-62289.rs:+1:10: +1:21
-        _5 = ShallowInitBox(move _4, u32); // scope 0 at $DIR/issue-62289.rs:+1:10: +1:21
-        StorageLive(_6);                 // scope 0 at $DIR/issue-62289.rs:+1:15: +1:20
-        StorageLive(_7);                 // scope 0 at $DIR/issue-62289.rs:+1:15: +1:19
-        _7 = Option::<u32>::None;        // scope 0 at $DIR/issue-62289.rs:+1:15: +1:19
-        _6 = <Option<u32> as Try>::branch(move _7) -> [return: bb2, unwind: bb12]; // scope 0 at $DIR/issue-62289.rs:+1:15: +1:20
+        StorageLive(_5);                 // scope 0 at $DIR/issue_62289.rs:+1:10: +1:21
+        _5 = ShallowInitBox(move _4, u32); // scope 0 at $DIR/issue_62289.rs:+1:10: +1:21
+        StorageLive(_6);                 // scope 0 at $DIR/issue_62289.rs:+1:15: +1:20
+        StorageLive(_7);                 // scope 0 at $DIR/issue_62289.rs:+1:15: +1:19
+        _7 = Option::<u32>::None;        // scope 0 at $DIR/issue_62289.rs:+1:15: +1:19
+        _6 = <Option<u32> as Try>::branch(move _7) -> [return: bb2, unwind: bb12]; // scope 0 at $DIR/issue_62289.rs:+1:15: +1:20
                                          // mir::Constant
-                                         // + span: $DIR/issue-62289.rs:9:15: 9:20
+                                         // + span: $DIR/issue_62289.rs:9:15: 9:20
                                          // + literal: Const { ty: fn(Option<u32>) -> ControlFlow<<Option<u32> as Try>::Residual, <Option<u32> as Try>::Output> {<Option<u32> as Try>::branch}, val: Value(<ZST>) }
     }
 
     bb2: {
-        StorageDead(_7);                 // scope 0 at $DIR/issue-62289.rs:+1:19: +1:20
-        _8 = discriminant(_6);           // scope 0 at $DIR/issue-62289.rs:+1:15: +1:20
-        switchInt(move _8) -> [0_isize: bb3, 1_isize: bb5, otherwise: bb4]; // scope 0 at $DIR/issue-62289.rs:+1:15: +1:20
+        StorageDead(_7);                 // scope 0 at $DIR/issue_62289.rs:+1:19: +1:20
+        _8 = discriminant(_6);           // scope 0 at $DIR/issue_62289.rs:+1:15: +1:20
+        switchInt(move _8) -> [0_isize: bb3, 1_isize: bb5, otherwise: bb4]; // scope 0 at $DIR/issue_62289.rs:+1:15: +1:20
     }
 
     bb3: {
-        StorageLive(_12);                // scope 0 at $DIR/issue-62289.rs:+1:15: +1:20
-        _12 = ((_6 as Continue).0: u32); // scope 0 at $DIR/issue-62289.rs:+1:15: +1:20
-        (*_5) = _12;                     // scope 5 at $DIR/issue-62289.rs:+1:15: +1:20
-        StorageDead(_12);                // scope 0 at $DIR/issue-62289.rs:+1:19: +1:20
-        _1 = move _5;                    // scope 0 at $DIR/issue-62289.rs:+1:10: +1:21
-        drop(_5) -> [return: bb7, unwind: bb11]; // scope 0 at $DIR/issue-62289.rs:+1:20: +1:21
+        StorageLive(_12);                // scope 0 at $DIR/issue_62289.rs:+1:15: +1:20
+        _12 = ((_6 as Continue).0: u32); // scope 0 at $DIR/issue_62289.rs:+1:15: +1:20
+        (*_5) = _12;                     // scope 5 at $DIR/issue_62289.rs:+1:15: +1:20
+        StorageDead(_12);                // scope 0 at $DIR/issue_62289.rs:+1:19: +1:20
+        _1 = move _5;                    // scope 0 at $DIR/issue_62289.rs:+1:10: +1:21
+        drop(_5) -> [return: bb7, unwind: bb11]; // scope 0 at $DIR/issue_62289.rs:+1:20: +1:21
     }
 
     bb4: {
-        unreachable;                     // scope 0 at $DIR/issue-62289.rs:+1:15: +1:20
+        unreachable;                     // scope 0 at $DIR/issue_62289.rs:+1:15: +1:20
     }
 
     bb5: {
-        StorageLive(_9);                 // scope 0 at $DIR/issue-62289.rs:+1:19: +1:20
-        _9 = ((_6 as Break).0: std::option::Option<std::convert::Infallible>); // scope 0 at $DIR/issue-62289.rs:+1:19: +1:20
-        StorageLive(_11);                // scope 3 at $DIR/issue-62289.rs:+1:19: +1:20
-        _11 = _9;                        // scope 3 at $DIR/issue-62289.rs:+1:19: +1:20
-        _0 = <Option<Box<u32>> as FromResidual<Option<Infallible>>>::from_residual(move _11) -> [return: bb6, unwind: bb12]; // scope 3 at $DIR/issue-62289.rs:+1:15: +1:20
+        StorageLive(_9);                 // scope 0 at $DIR/issue_62289.rs:+1:19: +1:20
+        _9 = ((_6 as Break).0: std::option::Option<std::convert::Infallible>); // scope 0 at $DIR/issue_62289.rs:+1:19: +1:20
+        StorageLive(_11);                // scope 3 at $DIR/issue_62289.rs:+1:19: +1:20
+        _11 = _9;                        // scope 3 at $DIR/issue_62289.rs:+1:19: +1:20
+        _0 = <Option<Box<u32>> as FromResidual<Option<Infallible>>>::from_residual(move _11) -> [return: bb6, unwind: bb12]; // scope 3 at $DIR/issue_62289.rs:+1:15: +1:20
                                          // mir::Constant
-                                         // + span: $DIR/issue-62289.rs:9:19: 9:20
+                                         // + span: $DIR/issue_62289.rs:9:19: 9:20
                                          // + literal: Const { ty: fn(Option<Infallible>) -> Option<Box<u32>> {<Option<Box<u32>> as FromResidual<Option<Infallible>>>::from_residual}, val: Value(<ZST>) }
     }
 
     bb6: {
-        StorageDead(_11);                // scope 3 at $DIR/issue-62289.rs:+1:19: +1:20
-        StorageDead(_9);                 // scope 0 at $DIR/issue-62289.rs:+1:19: +1:20
-        drop(_5) -> bb9;                 // scope 0 at $DIR/issue-62289.rs:+1:20: +1:21
+        StorageDead(_11);                // scope 3 at $DIR/issue_62289.rs:+1:19: +1:20
+        StorageDead(_9);                 // scope 0 at $DIR/issue_62289.rs:+1:19: +1:20
+        drop(_5) -> bb9;                 // scope 0 at $DIR/issue_62289.rs:+1:20: +1:21
     }
 
     bb7: {
-        StorageDead(_5);                 // scope 0 at $DIR/issue-62289.rs:+1:20: +1:21
-        _0 = Option::<Box<u32>>::Some(move _1); // scope 0 at $DIR/issue-62289.rs:+1:5: +1:22
-        drop(_1) -> bb8;                 // scope 0 at $DIR/issue-62289.rs:+1:21: +1:22
+        StorageDead(_5);                 // scope 0 at $DIR/issue_62289.rs:+1:20: +1:21
+        _0 = Option::<Box<u32>>::Some(move _1); // scope 0 at $DIR/issue_62289.rs:+1:5: +1:22
+        drop(_1) -> bb8;                 // scope 0 at $DIR/issue_62289.rs:+1:21: +1:22
     }
 
     bb8: {
-        StorageDead(_1);                 // scope 0 at $DIR/issue-62289.rs:+1:21: +1:22
-        StorageDead(_6);                 // scope 0 at $DIR/issue-62289.rs:+2:1: +2:2
-        goto -> bb10;                    // scope 0 at $DIR/issue-62289.rs:+2:2: +2:2
+        StorageDead(_1);                 // scope 0 at $DIR/issue_62289.rs:+1:21: +1:22
+        StorageDead(_6);                 // scope 0 at $DIR/issue_62289.rs:+2:1: +2:2
+        goto -> bb10;                    // scope 0 at $DIR/issue_62289.rs:+2:2: +2:2
     }
 
     bb9: {
-        StorageDead(_5);                 // scope 0 at $DIR/issue-62289.rs:+1:20: +1:21
-        StorageDead(_1);                 // scope 0 at $DIR/issue-62289.rs:+1:21: +1:22
-        StorageDead(_6);                 // scope 0 at $DIR/issue-62289.rs:+2:1: +2:2
-        goto -> bb10;                    // scope 0 at $DIR/issue-62289.rs:+2:2: +2:2
+        StorageDead(_5);                 // scope 0 at $DIR/issue_62289.rs:+1:20: +1:21
+        StorageDead(_1);                 // scope 0 at $DIR/issue_62289.rs:+1:21: +1:22
+        StorageDead(_6);                 // scope 0 at $DIR/issue_62289.rs:+2:1: +2:2
+        goto -> bb10;                    // scope 0 at $DIR/issue_62289.rs:+2:2: +2:2
     }
 
     bb10: {
-        return;                          // scope 0 at $DIR/issue-62289.rs:+2:2: +2:2
+        return;                          // scope 0 at $DIR/issue_62289.rs:+2:2: +2:2
     }
 
     bb11 (cleanup): {
-        drop(_1) -> bb13;                // scope 0 at $DIR/issue-62289.rs:+1:21: +1:22
+        drop(_1) -> bb13;                // scope 0 at $DIR/issue_62289.rs:+1:21: +1:22
     }
 
     bb12 (cleanup): {
-        drop(_5) -> bb13;                // scope 0 at $DIR/issue-62289.rs:+1:20: +1:21
+        drop(_5) -> bb13;                // scope 0 at $DIR/issue_62289.rs:+1:20: +1:21
     }
 
     bb13 (cleanup): {
-        resume;                          // scope 0 at $DIR/issue-62289.rs:+0:1: +2:2
+        resume;                          // scope 0 at $DIR/issue_62289.rs:+0:1: +2:2
     }
 }
diff --git a/src/test/mir-opt/issue_72181.bar.mir_map.0.mir b/src/test/mir-opt/issue_72181.bar.built.after.mir
similarity index 70%
rename from src/test/mir-opt/issue_72181.bar.mir_map.0.mir
rename to src/test/mir-opt/issue_72181.bar.built.after.mir
index 972ce1d50785..ebee89001b99 100644
--- a/src/test/mir-opt/issue_72181.bar.mir_map.0.mir
+++ b/src/test/mir-opt/issue_72181.bar.built.after.mir
@@ -1,17 +1,17 @@
-// MIR for `bar` 0 mir_map
+// MIR for `bar` after built
 
 fn bar(_1: [(Never, u32); 1]) -> u32 {
-    let mut _0: u32;                     // return place in scope 0 at $DIR/issue-72181.rs:+0:40: +0:43
-    let _2: u32;                         // in scope 0 at $DIR/issue-72181.rs:+0:13: +0:14
+    let mut _0: u32;                     // return place in scope 0 at $DIR/issue_72181.rs:+0:40: +0:43
+    let _2: u32;                         // in scope 0 at $DIR/issue_72181.rs:+0:13: +0:14
     scope 1 {
-        debug x => _2;                   // in scope 1 at $DIR/issue-72181.rs:+0:13: +0:14
+        debug x => _2;                   // in scope 1 at $DIR/issue_72181.rs:+0:13: +0:14
     }
 
     bb0: {
-        StorageLive(_2);                 // scope 0 at $DIR/issue-72181.rs:+0:13: +0:14
-        _2 = (_1[0 of 1].1: u32);        // scope 0 at $DIR/issue-72181.rs:+0:13: +0:14
-        _0 = _2;                         // scope 1 at $DIR/issue-72181.rs:+0:46: +0:47
-        StorageDead(_2);                 // scope 0 at $DIR/issue-72181.rs:+0:48: +0:49
-        return;                          // scope 0 at $DIR/issue-72181.rs:+0:49: +0:49
+        StorageLive(_2);                 // scope 0 at $DIR/issue_72181.rs:+0:13: +0:14
+        _2 = (_1[0 of 1].1: u32);        // scope 0 at $DIR/issue_72181.rs:+0:13: +0:14
+        _0 = _2;                         // scope 1 at $DIR/issue_72181.rs:+0:46: +0:47
+        StorageDead(_2);                 // scope 0 at $DIR/issue_72181.rs:+0:48: +0:49
+        return;                          // scope 0 at $DIR/issue_72181.rs:+0:49: +0:49
     }
 }
diff --git a/src/test/mir-opt/issue_72181.foo.mir_map.0.mir b/src/test/mir-opt/issue_72181.foo.built.after.mir
similarity index 71%
rename from src/test/mir-opt/issue_72181.foo.mir_map.0.mir
rename to src/test/mir-opt/issue_72181.foo.built.after.mir
index 534f131ea936..90c9785202a7 100644
--- a/src/test/mir-opt/issue_72181.foo.mir_map.0.mir
+++ b/src/test/mir-opt/issue_72181.foo.built.after.mir
@@ -1,27 +1,27 @@
-// MIR for `foo` 0 mir_map
+// MIR for `foo` after built
 
 fn foo(_1: [(Never, u32); 1]) -> u32 {
-    debug xs => _1;                      // in scope 0 at $DIR/issue-72181.rs:+0:8: +0:10
-    let mut _0: u32;                     // return place in scope 0 at $DIR/issue-72181.rs:+0:34: +0:37
-    let _2: usize;                       // in scope 0 at $DIR/issue-72181.rs:+0:43: +0:44
-    let mut _3: usize;                   // in scope 0 at $DIR/issue-72181.rs:+0:40: +0:45
-    let mut _4: bool;                    // in scope 0 at $DIR/issue-72181.rs:+0:40: +0:45
+    debug xs => _1;                      // in scope 0 at $DIR/issue_72181.rs:+0:8: +0:10
+    let mut _0: u32;                     // return place in scope 0 at $DIR/issue_72181.rs:+0:34: +0:37
+    let _2: usize;                       // in scope 0 at $DIR/issue_72181.rs:+0:43: +0:44
+    let mut _3: usize;                   // in scope 0 at $DIR/issue_72181.rs:+0:40: +0:45
+    let mut _4: bool;                    // in scope 0 at $DIR/issue_72181.rs:+0:40: +0:45
 
     bb0: {
-        StorageLive(_2);                 // scope 0 at $DIR/issue-72181.rs:+0:43: +0:44
-        _2 = const 0_usize;              // scope 0 at $DIR/issue-72181.rs:+0:43: +0:44
-        _3 = Len(_1);                    // scope 0 at $DIR/issue-72181.rs:+0:40: +0:45
-        _4 = Lt(_2, _3);                 // scope 0 at $DIR/issue-72181.rs:+0:40: +0:45
-        assert(move _4, "index out of bounds: the length is {} but the index is {}", move _3, _2) -> [success: bb1, unwind: bb2]; // scope 0 at $DIR/issue-72181.rs:+0:40: +0:45
+        StorageLive(_2);                 // scope 0 at $DIR/issue_72181.rs:+0:43: +0:44
+        _2 = const 0_usize;              // scope 0 at $DIR/issue_72181.rs:+0:43: +0:44
+        _3 = Len(_1);                    // scope 0 at $DIR/issue_72181.rs:+0:40: +0:45
+        _4 = Lt(_2, _3);                 // scope 0 at $DIR/issue_72181.rs:+0:40: +0:45
+        assert(move _4, "index out of bounds: the length is {} but the index is {}", move _3, _2) -> [success: bb1, unwind: bb2]; // scope 0 at $DIR/issue_72181.rs:+0:40: +0:45
     }
 
     bb1: {
-        _0 = (_1[_2].1: u32);            // scope 0 at $DIR/issue-72181.rs:+0:40: +0:47
-        StorageDead(_2);                 // scope 0 at $DIR/issue-72181.rs:+0:48: +0:49
-        return;                          // scope 0 at $DIR/issue-72181.rs:+0:49: +0:49
+        _0 = (_1[_2].1: u32);            // scope 0 at $DIR/issue_72181.rs:+0:40: +0:47
+        StorageDead(_2);                 // scope 0 at $DIR/issue_72181.rs:+0:48: +0:49
+        return;                          // scope 0 at $DIR/issue_72181.rs:+0:49: +0:49
     }
 
     bb2 (cleanup): {
-        resume;                          // scope 0 at $DIR/issue-72181.rs:+0:1: +0:49
+        resume;                          // scope 0 at $DIR/issue_72181.rs:+0:1: +0:49
     }
 }
diff --git a/src/test/mir-opt/issue_72181.main.mir_map.0.mir b/src/test/mir-opt/issue_72181.main.built.after.mir
similarity index 72%
rename from src/test/mir-opt/issue_72181.main.mir_map.0.mir
rename to src/test/mir-opt/issue_72181.main.built.after.mir
index 425906f84fcd..e8683692770d 100644
--- a/src/test/mir-opt/issue_72181.main.mir_map.0.mir
+++ b/src/test/mir-opt/issue_72181.main.built.after.mir
@@ -1,18 +1,18 @@
-// MIR for `main` 0 mir_map
+// MIR for `main` after built
 
 fn main() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/issue-72181.rs:+0:11: +0:11
-    let mut _1: usize;                   // in scope 0 at $DIR/issue-72181.rs:+1:13: +1:34
-    let mut _3: Foo;                     // in scope 0 at $DIR/issue-72181.rs:+3:14: +3:27
-    let mut _4: Foo;                     // in scope 0 at $DIR/issue-72181.rs:+3:29: +3:42
-    let mut _5: u64;                     // in scope 0 at $DIR/issue-72181.rs:+4:13: +4:30
-    let _6: usize;                       // in scope 0 at $DIR/issue-72181.rs:+4:24: +4:25
-    let mut _7: usize;                   // in scope 0 at $DIR/issue-72181.rs:+4:22: +4:26
-    let mut _8: bool;                    // in scope 0 at $DIR/issue-72181.rs:+4:22: +4:26
+    let mut _0: ();                      // return place in scope 0 at $DIR/issue_72181.rs:+0:11: +0:11
+    let mut _1: usize;                   // in scope 0 at $DIR/issue_72181.rs:+1:13: +1:34
+    let mut _3: Foo;                     // in scope 0 at $DIR/issue_72181.rs:+3:14: +3:27
+    let mut _4: Foo;                     // in scope 0 at $DIR/issue_72181.rs:+3:29: +3:42
+    let mut _5: u64;                     // in scope 0 at $DIR/issue_72181.rs:+4:13: +4:30
+    let _6: usize;                       // in scope 0 at $DIR/issue_72181.rs:+4:24: +4:25
+    let mut _7: usize;                   // in scope 0 at $DIR/issue_72181.rs:+4:22: +4:26
+    let mut _8: bool;                    // in scope 0 at $DIR/issue_72181.rs:+4:22: +4:26
     scope 1 {
-        let _2: [Foo; 2];                // in scope 1 at $DIR/issue-72181.rs:+3:9: +3:10
+        let _2: [Foo; 2];                // in scope 1 at $DIR/issue_72181.rs:+3:9: +3:10
         scope 2 {
-            debug f => _2;               // in scope 2 at $DIR/issue-72181.rs:+3:9: +3:10
+            debug f => _2;               // in scope 2 at $DIR/issue_72181.rs:+3:9: +3:10
             scope 3 {
             }
             scope 4 {
@@ -21,42 +21,42 @@ fn main() -> () {
     }
 
     bb0: {
-        StorageLive(_1);                 // scope 0 at $DIR/issue-72181.rs:+1:13: +1:34
-        _1 = std::mem::size_of::<Foo>() -> [return: bb1, unwind: bb3]; // scope 0 at $DIR/issue-72181.rs:+1:13: +1:34
+        StorageLive(_1);                 // scope 0 at $DIR/issue_72181.rs:+1:13: +1:34
+        _1 = std::mem::size_of::<Foo>() -> [return: bb1, unwind: bb3]; // scope 0 at $DIR/issue_72181.rs:+1:13: +1:34
                                          // mir::Constant
-                                         // + span: $DIR/issue-72181.rs:24:13: 24:32
+                                         // + span: $DIR/issue_72181.rs:24:13: 24:32
                                          // + literal: Const { ty: fn() -> usize {std::mem::size_of::<Foo>}, val: Value(<ZST>) }
     }
 
     bb1: {
-        StorageDead(_1);                 // scope 0 at $DIR/issue-72181.rs:+1:34: +1:35
-        StorageLive(_2);                 // scope 1 at $DIR/issue-72181.rs:+3:9: +3:10
-        StorageLive(_3);                 // scope 1 at $DIR/issue-72181.rs:+3:14: +3:27
-        _3 = Foo { a: const 42_u64 };    // scope 1 at $DIR/issue-72181.rs:+3:14: +3:27
-        StorageLive(_4);                 // scope 1 at $DIR/issue-72181.rs:+3:29: +3:42
-        _4 = Foo { a: const 10_u64 };    // scope 1 at $DIR/issue-72181.rs:+3:29: +3:42
-        _2 = [move _3, move _4];         // scope 1 at $DIR/issue-72181.rs:+3:13: +3:43
-        StorageDead(_4);                 // scope 1 at $DIR/issue-72181.rs:+3:42: +3:43
-        StorageDead(_3);                 // scope 1 at $DIR/issue-72181.rs:+3:42: +3:43
-        FakeRead(ForLet(None), _2);      // scope 1 at $DIR/issue-72181.rs:+3:9: +3:10
-        StorageLive(_5);                 // scope 2 at $DIR/issue-72181.rs:+4:13: +4:30
-        StorageLive(_6);                 // scope 4 at $DIR/issue-72181.rs:+4:24: +4:25
-        _6 = const 0_usize;              // scope 4 at $DIR/issue-72181.rs:+4:24: +4:25
-        _7 = Len(_2);                    // scope 4 at $DIR/issue-72181.rs:+4:22: +4:26
-        _8 = Lt(_6, _7);                 // scope 4 at $DIR/issue-72181.rs:+4:22: +4:26
-        assert(move _8, "index out of bounds: the length is {} but the index is {}", move _7, _6) -> [success: bb2, unwind: bb3]; // scope 4 at $DIR/issue-72181.rs:+4:22: +4:26
+        StorageDead(_1);                 // scope 0 at $DIR/issue_72181.rs:+1:34: +1:35
+        StorageLive(_2);                 // scope 1 at $DIR/issue_72181.rs:+3:9: +3:10
+        StorageLive(_3);                 // scope 1 at $DIR/issue_72181.rs:+3:14: +3:27
+        _3 = Foo { a: const 42_u64 };    // scope 1 at $DIR/issue_72181.rs:+3:14: +3:27
+        StorageLive(_4);                 // scope 1 at $DIR/issue_72181.rs:+3:29: +3:42
+        _4 = Foo { a: const 10_u64 };    // scope 1 at $DIR/issue_72181.rs:+3:29: +3:42
+        _2 = [move _3, move _4];         // scope 1 at $DIR/issue_72181.rs:+3:13: +3:43
+        StorageDead(_4);                 // scope 1 at $DIR/issue_72181.rs:+3:42: +3:43
+        StorageDead(_3);                 // scope 1 at $DIR/issue_72181.rs:+3:42: +3:43
+        FakeRead(ForLet(None), _2);      // scope 1 at $DIR/issue_72181.rs:+3:9: +3:10
+        StorageLive(_5);                 // scope 2 at $DIR/issue_72181.rs:+4:13: +4:30
+        StorageLive(_6);                 // scope 4 at $DIR/issue_72181.rs:+4:24: +4:25
+        _6 = const 0_usize;              // scope 4 at $DIR/issue_72181.rs:+4:24: +4:25
+        _7 = Len(_2);                    // scope 4 at $DIR/issue_72181.rs:+4:22: +4:26
+        _8 = Lt(_6, _7);                 // scope 4 at $DIR/issue_72181.rs:+4:22: +4:26
+        assert(move _8, "index out of bounds: the length is {} but the index is {}", move _7, _6) -> [success: bb2, unwind: bb3]; // scope 4 at $DIR/issue_72181.rs:+4:22: +4:26
     }
 
     bb2: {
-        _5 = (_2[_6].0: u64);            // scope 4 at $DIR/issue-72181.rs:+4:22: +4:28
-        StorageDead(_6);                 // scope 2 at $DIR/issue-72181.rs:+4:30: +4:31
-        StorageDead(_5);                 // scope 2 at $DIR/issue-72181.rs:+4:30: +4:31
-        _0 = const ();                   // scope 0 at $DIR/issue-72181.rs:+0:11: +5:2
-        StorageDead(_2);                 // scope 1 at $DIR/issue-72181.rs:+5:1: +5:2
-        return;                          // scope 0 at $DIR/issue-72181.rs:+5:2: +5:2
+        _5 = (_2[_6].0: u64);            // scope 4 at $DIR/issue_72181.rs:+4:22: +4:28
+        StorageDead(_6);                 // scope 2 at $DIR/issue_72181.rs:+4:30: +4:31
+        StorageDead(_5);                 // scope 2 at $DIR/issue_72181.rs:+4:30: +4:31
+        _0 = const ();                   // scope 0 at $DIR/issue_72181.rs:+0:11: +5:2
+        StorageDead(_2);                 // scope 1 at $DIR/issue_72181.rs:+5:1: +5:2
+        return;                          // scope 0 at $DIR/issue_72181.rs:+5:2: +5:2
     }
 
     bb3 (cleanup): {
-        resume;                          // scope 0 at $DIR/issue-72181.rs:+0:1: +5:2
+        resume;                          // scope 0 at $DIR/issue_72181.rs:+0:1: +5:2
     }
 }
diff --git a/src/test/mir-opt/issue-72181.rs b/src/test/mir-opt/issue_72181.rs
similarity index 76%
rename from src/test/mir-opt/issue-72181.rs
rename to src/test/mir-opt/issue_72181.rs
index ebb5f5042fcc..6a32d4bbee2f 100644
--- a/src/test/mir-opt/issue-72181.rs
+++ b/src/test/mir-opt/issue_72181.rs
@@ -12,14 +12,14 @@ union Foo {
 }
 
 
-// EMIT_MIR issue_72181.foo.mir_map.0.mir
+// EMIT_MIR issue_72181.foo.built.after.mir
 fn foo(xs: [(Never, u32); 1]) -> u32 { xs[0].1 }
 
-// EMIT_MIR issue_72181.bar.mir_map.0.mir
+// EMIT_MIR issue_72181.bar.built.after.mir
 fn bar([(_, x)]: [(Never, u32); 1]) -> u32 { x }
 
 
-// EMIT_MIR issue_72181.main.mir_map.0.mir
+// EMIT_MIR issue_72181.main.built.after.mir
 fn main() {
     let _ = mem::size_of::<Foo>();
 
diff --git a/src/test/mir-opt/issue_72181_1.f.mir_map.0.mir b/src/test/mir-opt/issue_72181_1.f.built.after.mir
similarity index 70%
rename from src/test/mir-opt/issue_72181_1.f.mir_map.0.mir
rename to src/test/mir-opt/issue_72181_1.f.built.after.mir
index e1a35d88bf1d..4086da520113 100644
--- a/src/test/mir-opt/issue_72181_1.f.mir_map.0.mir
+++ b/src/test/mir-opt/issue_72181_1.f.built.after.mir
@@ -1,29 +1,29 @@
-// MIR for `f` 0 mir_map
+// MIR for `f` after built
 
 fn f(_1: Void) -> ! {
-    debug v => _1;                       // in scope 0 at $DIR/issue-72181-1.rs:+0:6: +0:7
-    let mut _0: !;                       // return place in scope 0 at $DIR/issue-72181-1.rs:+0:18: +0:19
-    let mut _2: !;                       // in scope 0 at $DIR/issue-72181-1.rs:+0:20: +2:2
-    let mut _3: !;                       // in scope 0 at $DIR/issue-72181-1.rs:+1:5: +1:15
+    debug v => _1;                       // in scope 0 at $DIR/issue_72181_1.rs:+0:6: +0:7
+    let mut _0: !;                       // return place in scope 0 at $DIR/issue_72181_1.rs:+0:18: +0:19
+    let mut _2: !;                       // in scope 0 at $DIR/issue_72181_1.rs:+0:20: +2:2
+    let mut _3: !;                       // in scope 0 at $DIR/issue_72181_1.rs:+1:5: +1:15
 
     bb0: {
-        StorageLive(_2);                 // scope 0 at $DIR/issue-72181-1.rs:+0:20: +2:2
-        StorageLive(_3);                 // scope 0 at $DIR/issue-72181-1.rs:+1:5: +1:15
-        FakeRead(ForMatchedPlace(None), _1); // scope 0 at $DIR/issue-72181-1.rs:+1:11: +1:12
-        unreachable;                     // scope 0 at $DIR/issue-72181-1.rs:+1:11: +1:12
+        StorageLive(_2);                 // scope 0 at $DIR/issue_72181_1.rs:+0:20: +2:2
+        StorageLive(_3);                 // scope 0 at $DIR/issue_72181_1.rs:+1:5: +1:15
+        FakeRead(ForMatchedPlace(None), _1); // scope 0 at $DIR/issue_72181_1.rs:+1:11: +1:12
+        unreachable;                     // scope 0 at $DIR/issue_72181_1.rs:+1:11: +1:12
     }
 
     bb1: {
-        unreachable;                     // scope 0 at $DIR/issue-72181-1.rs:+1:5: +1:15
+        unreachable;                     // scope 0 at $DIR/issue_72181_1.rs:+1:5: +1:15
     }
 
     bb2: {
-        StorageDead(_3);                 // scope 0 at $DIR/issue-72181-1.rs:+1:14: +1:15
-        unreachable;                     // scope 0 at $DIR/issue-72181-1.rs:+0:20: +2:2
+        StorageDead(_3);                 // scope 0 at $DIR/issue_72181_1.rs:+1:14: +1:15
+        unreachable;                     // scope 0 at $DIR/issue_72181_1.rs:+0:20: +2:2
     }
 
     bb3: {
-        StorageDead(_2);                 // scope 0 at $DIR/issue-72181-1.rs:+2:1: +2:2
-        return;                          // scope 0 at $DIR/issue-72181-1.rs:+2:2: +2:2
+        StorageDead(_2);                 // scope 0 at $DIR/issue_72181_1.rs:+2:1: +2:2
+        return;                          // scope 0 at $DIR/issue_72181_1.rs:+2:2: +2:2
     }
 }
diff --git a/src/test/mir-opt/issue_72181_1.main.mir_map.0.mir b/src/test/mir-opt/issue_72181_1.main.built.after.mir
similarity index 68%
rename from src/test/mir-opt/issue_72181_1.main.mir_map.0.mir
rename to src/test/mir-opt/issue_72181_1.main.built.after.mir
index 336693337fb5..2172f3aa9e28 100644
--- a/src/test/mir-opt/issue_72181_1.main.mir_map.0.mir
+++ b/src/test/mir-opt/issue_72181_1.main.built.after.mir
@@ -1,57 +1,57 @@
-// MIR for `main` 0 mir_map
+// MIR for `main` after built
 
 | User Type Annotations
-| 0: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(Void) }, span: $DIR/issue-72181-1.rs:16:12: 16:16, inferred_ty: Void
-| 1: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(Void) }, span: $DIR/issue-72181-1.rs:16:12: 16:16, inferred_ty: Void
+| 0: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(Void) }, span: $DIR/issue_72181_1.rs:16:12: 16:16, inferred_ty: Void
+| 1: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(Void) }, span: $DIR/issue_72181_1.rs:16:12: 16:16, inferred_ty: Void
 |
 fn main() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/issue-72181-1.rs:+0:11: +0:11
-    let mut _1: !;                       // in scope 0 at $DIR/issue-72181-1.rs:+0:11: +6:2
-    let _2: Void as UserTypeProjection { base: UserType(0), projs: [] }; // in scope 0 at $DIR/issue-72181-1.rs:+1:9: +1:10
-    let mut _3: ();                      // in scope 0 at $DIR/issue-72181-1.rs:+2:41: +2:43
-    let _4: !;                           // in scope 0 at $DIR/issue-72181-1.rs:+5:5: +5:9
-    let mut _5: Void;                    // in scope 0 at $DIR/issue-72181-1.rs:+5:7: +5:8
+    let mut _0: ();                      // return place in scope 0 at $DIR/issue_72181_1.rs:+0:11: +0:11
+    let mut _1: !;                       // in scope 0 at $DIR/issue_72181_1.rs:+0:11: +6:2
+    let _2: Void as UserTypeProjection { base: UserType(0), projs: [] }; // in scope 0 at $DIR/issue_72181_1.rs:+1:9: +1:10
+    let mut _3: ();                      // in scope 0 at $DIR/issue_72181_1.rs:+2:41: +2:43
+    let _4: !;                           // in scope 0 at $DIR/issue_72181_1.rs:+5:5: +5:9
+    let mut _5: Void;                    // in scope 0 at $DIR/issue_72181_1.rs:+5:7: +5:8
     scope 1 {
-        debug v => _2;                   // in scope 1 at $DIR/issue-72181-1.rs:+1:9: +1:10
+        debug v => _2;                   // in scope 1 at $DIR/issue_72181_1.rs:+1:9: +1:10
     }
     scope 2 {
     }
 
     bb0: {
-        StorageLive(_2);                 // scope 0 at $DIR/issue-72181-1.rs:+1:9: +1:10
-        StorageLive(_3);                 // scope 2 at $DIR/issue-72181-1.rs:+2:41: +2:43
-        _3 = ();                         // scope 2 at $DIR/issue-72181-1.rs:+2:41: +2:43
-        _2 = transmute::<(), Void>(move _3) -> bb4; // scope 2 at $DIR/issue-72181-1.rs:+2:9: +2:44
+        StorageLive(_2);                 // scope 0 at $DIR/issue_72181_1.rs:+1:9: +1:10
+        StorageLive(_3);                 // scope 2 at $DIR/issue_72181_1.rs:+2:41: +2:43
+        _3 = ();                         // scope 2 at $DIR/issue_72181_1.rs:+2:41: +2:43
+        _2 = transmute::<(), Void>(move _3) -> bb4; // scope 2 at $DIR/issue_72181_1.rs:+2:9: +2:44
                                          // mir::Constant
-                                         // + span: $DIR/issue-72181-1.rs:17:9: 17:40
+                                         // + span: $DIR/issue_72181_1.rs:17:9: 17:40
                                          // + literal: Const { ty: unsafe extern "rust-intrinsic" fn(()) -> Void {transmute::<(), Void>}, val: Value(<ZST>) }
     }
 
     bb1: {
-        StorageDead(_3);                 // scope 2 at $DIR/issue-72181-1.rs:+2:43: +2:44
-        FakeRead(ForLet(None), _2);      // scope 0 at $DIR/issue-72181-1.rs:+1:9: +1:10
-        AscribeUserType(_2, o, UserTypeProjection { base: UserType(1), projs: [] }); // scope 0 at $DIR/issue-72181-1.rs:+1:12: +1:16
-        StorageLive(_4);                 // scope 1 at $DIR/issue-72181-1.rs:+5:5: +5:9
-        StorageLive(_5);                 // scope 1 at $DIR/issue-72181-1.rs:+5:7: +5:8
-        _5 = move _2;                    // scope 1 at $DIR/issue-72181-1.rs:+5:7: +5:8
-        _4 = f(move _5) -> bb4;          // scope 1 at $DIR/issue-72181-1.rs:+5:5: +5:9
+        StorageDead(_3);                 // scope 2 at $DIR/issue_72181_1.rs:+2:43: +2:44
+        FakeRead(ForLet(None), _2);      // scope 0 at $DIR/issue_72181_1.rs:+1:9: +1:10
+        AscribeUserType(_2, o, UserTypeProjection { base: UserType(1), projs: [] }); // scope 0 at $DIR/issue_72181_1.rs:+1:12: +1:16
+        StorageLive(_4);                 // scope 1 at $DIR/issue_72181_1.rs:+5:5: +5:9
+        StorageLive(_5);                 // scope 1 at $DIR/issue_72181_1.rs:+5:7: +5:8
+        _5 = move _2;                    // scope 1 at $DIR/issue_72181_1.rs:+5:7: +5:8
+        _4 = f(move _5) -> bb4;          // scope 1 at $DIR/issue_72181_1.rs:+5:5: +5:9
                                          // mir::Constant
-                                         // + span: $DIR/issue-72181-1.rs:20:5: 20:6
+                                         // + span: $DIR/issue_72181_1.rs:20:5: 20:6
                                          // + literal: Const { ty: fn(Void) -> ! {f}, val: Value(<ZST>) }
     }
 
     bb2: {
-        StorageDead(_5);                 // scope 1 at $DIR/issue-72181-1.rs:+5:8: +5:9
-        StorageDead(_4);                 // scope 1 at $DIR/issue-72181-1.rs:+5:9: +5:10
-        StorageDead(_2);                 // scope 0 at $DIR/issue-72181-1.rs:+6:1: +6:2
-        unreachable;                     // scope 0 at $DIR/issue-72181-1.rs:+0:11: +6:2
+        StorageDead(_5);                 // scope 1 at $DIR/issue_72181_1.rs:+5:8: +5:9
+        StorageDead(_4);                 // scope 1 at $DIR/issue_72181_1.rs:+5:9: +5:10
+        StorageDead(_2);                 // scope 0 at $DIR/issue_72181_1.rs:+6:1: +6:2
+        unreachable;                     // scope 0 at $DIR/issue_72181_1.rs:+0:11: +6:2
     }
 
     bb3: {
-        return;                          // scope 0 at $DIR/issue-72181-1.rs:+6:2: +6:2
+        return;                          // scope 0 at $DIR/issue_72181_1.rs:+6:2: +6:2
     }
 
     bb4 (cleanup): {
-        resume;                          // scope 0 at $DIR/issue-72181-1.rs:+0:1: +6:2
+        resume;                          // scope 0 at $DIR/issue_72181_1.rs:+0:1: +6:2
     }
 }
diff --git a/src/test/mir-opt/issue-72181-1.rs b/src/test/mir-opt/issue_72181_1.rs
similarity index 78%
rename from src/test/mir-opt/issue-72181-1.rs
rename to src/test/mir-opt/issue_72181_1.rs
index 91e98adbe804..8ae2599ec73f 100644
--- a/src/test/mir-opt/issue-72181-1.rs
+++ b/src/test/mir-opt/issue_72181_1.rs
@@ -6,12 +6,12 @@
 
 enum Void {}
 
-// EMIT_MIR issue_72181_1.f.mir_map.0.mir
+// EMIT_MIR issue_72181_1.f.built.after.mir
 fn f(v: Void) -> ! {
     match v {}
 }
 
-// EMIT_MIR issue_72181_1.main.mir_map.0.mir
+// EMIT_MIR issue_72181_1.main.built.after.mir
 fn main() {
     let v: Void = unsafe {
         std::mem::transmute::<(), Void>(())
diff --git a/src/test/mir-opt/issue_73223.main.SimplifyArmIdentity.diff b/src/test/mir-opt/issue_73223.main.SimplifyArmIdentity.diff
index 269e4e326175..c9a9511586d7 100644
--- a/src/test/mir-opt/issue_73223.main.SimplifyArmIdentity.diff
+++ b/src/test/mir-opt/issue_73223.main.SimplifyArmIdentity.diff
@@ -2,18 +2,18 @@
 + // MIR for `main` after SimplifyArmIdentity
   
   fn main() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/issue-73223.rs:+0:11: +0:11
-      let _1: i32;                         // in scope 0 at $DIR/issue-73223.rs:+1:9: +1:14
-      let mut _2: std::option::Option<i32>; // in scope 0 at $DIR/issue-73223.rs:+1:23: +1:30
-      let mut _3: isize;                   // in scope 0 at $DIR/issue-73223.rs:+2:9: +2:16
-      let _4: i32;                         // in scope 0 at $DIR/issue-73223.rs:+2:14: +2:15
-      let mut _5: !;                       // in scope 0 at $DIR/issue-73223.rs:+3:17: +3:23
-      let mut _7: i32;                     // in scope 0 at $DIR/issue-73223.rs:+6:22: +6:27
+      let mut _0: ();                      // return place in scope 0 at $DIR/issue_73223.rs:+0:11: +0:11
+      let _1: i32;                         // in scope 0 at $DIR/issue_73223.rs:+1:9: +1:14
+      let mut _2: std::option::Option<i32>; // in scope 0 at $DIR/issue_73223.rs:+1:23: +1:30
+      let mut _3: isize;                   // in scope 0 at $DIR/issue_73223.rs:+2:9: +2:16
+      let _4: i32;                         // in scope 0 at $DIR/issue_73223.rs:+2:14: +2:15
+      let mut _5: !;                       // in scope 0 at $DIR/issue_73223.rs:+3:17: +3:23
+      let mut _7: i32;                     // in scope 0 at $DIR/issue_73223.rs:+6:22: +6:27
       let _8: ();                          // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
       let mut _9: (&i32, &i32);            // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
       let mut _10: &i32;                   // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
       let mut _11: &i32;                   // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-      let _12: i32;                        // in scope 0 at $DIR/issue-73223.rs:+7:23: +7:24
+      let _12: i32;                        // in scope 0 at $DIR/issue_73223.rs:+7:23: +7:24
       let mut _15: bool;                   // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
       let mut _16: bool;                   // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
       let mut _17: i32;                    // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
@@ -27,10 +27,10 @@
       let _26: &i32;                       // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
       let mut _27: std::option::Option<std::fmt::Arguments<'_>>; // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
       scope 1 {
-          debug split => _1;               // in scope 1 at $DIR/issue-73223.rs:+1:9: +1:14
-          let _6: std::option::Option<i32>; // in scope 1 at $DIR/issue-73223.rs:+6:9: +6:14
+          debug split => _1;               // in scope 1 at $DIR/issue_73223.rs:+1:9: +1:14
+          let _6: std::option::Option<i32>; // in scope 1 at $DIR/issue_73223.rs:+6:9: +6:14
           scope 3 {
-              debug _prev => _6;           // in scope 3 at $DIR/issue-73223.rs:+6:9: +6:14
+              debug _prev => _6;           // in scope 3 at $DIR/issue_73223.rs:+6:9: +6:14
               let _13: &i32;               // in scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
               let _14: &i32;               // in scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
               let mut _28: &i32;           // in scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
@@ -45,43 +45,43 @@
           }
       }
       scope 2 {
-          debug v => _4;                   // in scope 2 at $DIR/issue-73223.rs:+2:14: +2:15
+          debug v => _4;                   // in scope 2 at $DIR/issue_73223.rs:+2:14: +2:15
       }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/issue-73223.rs:+1:9: +1:14
-          StorageLive(_2);                 // scope 0 at $DIR/issue-73223.rs:+1:23: +1:30
-          Deinit(_2);                      // scope 0 at $DIR/issue-73223.rs:+1:23: +1:30
-          ((_2 as Some).0: i32) = const 1_i32; // scope 0 at $DIR/issue-73223.rs:+1:23: +1:30
-          discriminant(_2) = 1;            // scope 0 at $DIR/issue-73223.rs:+1:23: +1:30
-          _3 = const 1_isize;              // scope 0 at $DIR/issue-73223.rs:+1:23: +1:30
-          goto -> bb3;                     // scope 0 at $DIR/issue-73223.rs:+1:17: +1:30
+          StorageLive(_1);                 // scope 0 at $DIR/issue_73223.rs:+1:9: +1:14
+          StorageLive(_2);                 // scope 0 at $DIR/issue_73223.rs:+1:23: +1:30
+          Deinit(_2);                      // scope 0 at $DIR/issue_73223.rs:+1:23: +1:30
+          ((_2 as Some).0: i32) = const 1_i32; // scope 0 at $DIR/issue_73223.rs:+1:23: +1:30
+          discriminant(_2) = 1;            // scope 0 at $DIR/issue_73223.rs:+1:23: +1:30
+          _3 = const 1_isize;              // scope 0 at $DIR/issue_73223.rs:+1:23: +1:30
+          goto -> bb3;                     // scope 0 at $DIR/issue_73223.rs:+1:17: +1:30
       }
   
       bb1: {
-          nop;                             // scope 0 at $DIR/issue-73223.rs:+3:17: +3:23
-          StorageDead(_2);                 // scope 0 at $DIR/issue-73223.rs:+4:6: +4:7
-          StorageDead(_1);                 // scope 0 at $DIR/issue-73223.rs:+8:1: +8:2
-          return;                          // scope 0 at $DIR/issue-73223.rs:+8:2: +8:2
+          nop;                             // scope 0 at $DIR/issue_73223.rs:+3:17: +3:23
+          StorageDead(_2);                 // scope 0 at $DIR/issue_73223.rs:+4:6: +4:7
+          StorageDead(_1);                 // scope 0 at $DIR/issue_73223.rs:+8:1: +8:2
+          return;                          // scope 0 at $DIR/issue_73223.rs:+8:2: +8:2
       }
   
       bb2: {
-          unreachable;                     // scope 0 at $DIR/issue-73223.rs:+1:23: +1:30
+          unreachable;                     // scope 0 at $DIR/issue_73223.rs:+1:23: +1:30
       }
   
       bb3: {
-          StorageLive(_4);                 // scope 0 at $DIR/issue-73223.rs:+2:14: +2:15
-          _4 = ((_2 as Some).0: i32);      // scope 0 at $DIR/issue-73223.rs:+2:14: +2:15
-          _1 = _4;                         // scope 2 at $DIR/issue-73223.rs:+2:20: +2:21
-          StorageDead(_4);                 // scope 0 at $DIR/issue-73223.rs:+2:20: +2:21
-          StorageDead(_2);                 // scope 0 at $DIR/issue-73223.rs:+4:6: +4:7
-          StorageLive(_6);                 // scope 1 at $DIR/issue-73223.rs:+6:9: +6:14
-          StorageLive(_7);                 // scope 1 at $DIR/issue-73223.rs:+6:22: +6:27
-          _7 = _1;                         // scope 1 at $DIR/issue-73223.rs:+6:22: +6:27
-          Deinit(_6);                      // scope 1 at $DIR/issue-73223.rs:+6:17: +6:28
-          ((_6 as Some).0: i32) = move _7; // scope 1 at $DIR/issue-73223.rs:+6:17: +6:28
-          discriminant(_6) = 1;            // scope 1 at $DIR/issue-73223.rs:+6:17: +6:28
-          StorageDead(_7);                 // scope 1 at $DIR/issue-73223.rs:+6:27: +6:28
+          StorageLive(_4);                 // scope 0 at $DIR/issue_73223.rs:+2:14: +2:15
+          _4 = ((_2 as Some).0: i32);      // scope 0 at $DIR/issue_73223.rs:+2:14: +2:15
+          _1 = _4;                         // scope 2 at $DIR/issue_73223.rs:+2:20: +2:21
+          StorageDead(_4);                 // scope 0 at $DIR/issue_73223.rs:+2:20: +2:21
+          StorageDead(_2);                 // scope 0 at $DIR/issue_73223.rs:+4:6: +4:7
+          StorageLive(_6);                 // scope 1 at $DIR/issue_73223.rs:+6:9: +6:14
+          StorageLive(_7);                 // scope 1 at $DIR/issue_73223.rs:+6:22: +6:27
+          _7 = _1;                         // scope 1 at $DIR/issue_73223.rs:+6:22: +6:27
+          Deinit(_6);                      // scope 1 at $DIR/issue_73223.rs:+6:17: +6:28
+          ((_6 as Some).0: i32) = move _7; // scope 1 at $DIR/issue_73223.rs:+6:17: +6:28
+          discriminant(_6) = 1;            // scope 1 at $DIR/issue_73223.rs:+6:17: +6:28
+          StorageDead(_7);                 // scope 1 at $DIR/issue_73223.rs:+6:27: +6:28
           StorageLive(_8);                 // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
           StorageLive(_9);                 // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
           StorageLive(_10);                // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
@@ -152,10 +152,10 @@
           StorageDead(_13);                // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
           StorageDead(_9);                 // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
           StorageDead(_8);                 // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          nop;                             // scope 0 at $DIR/issue-73223.rs:+0:11: +8:2
-          StorageDead(_6);                 // scope 1 at $DIR/issue-73223.rs:+8:1: +8:2
-          StorageDead(_1);                 // scope 0 at $DIR/issue-73223.rs:+8:1: +8:2
-          return;                          // scope 0 at $DIR/issue-73223.rs:+8:2: +8:2
+          nop;                             // scope 0 at $DIR/issue_73223.rs:+0:11: +8:2
+          StorageDead(_6);                 // scope 1 at $DIR/issue_73223.rs:+8:1: +8:2
+          StorageDead(_1);                 // scope 0 at $DIR/issue_73223.rs:+8:1: +8:2
+          return;                          // scope 0 at $DIR/issue_73223.rs:+8:2: +8:2
       }
   }
   
diff --git a/src/test/mir-opt/issue-73223.rs b/src/test/mir-opt/issue_73223.rs
similarity index 100%
rename from src/test/mir-opt/issue-73223.rs
rename to src/test/mir-opt/issue_73223.rs
diff --git a/src/test/mir-opt/issue_78192.f.InstCombine.diff b/src/test/mir-opt/issue_78192.f.InstCombine.diff
index 8ec94d65fda5..116ca304c993 100644
--- a/src/test/mir-opt/issue_78192.f.InstCombine.diff
+++ b/src/test/mir-opt/issue_78192.f.InstCombine.diff
@@ -2,28 +2,28 @@
 + // MIR for `f` after InstCombine
   
   fn f(_1: &T) -> *const T {
-      debug a => _1;                       // in scope 0 at $DIR/issue-78192.rs:+0:13: +0:14
-      let mut _0: *const T;                // return place in scope 0 at $DIR/issue-78192.rs:+0:23: +0:31
-      let _2: &*const T;                   // in scope 0 at $DIR/issue-78192.rs:+1:9: +1:10
-      let _3: &*const T;                   // in scope 0 at $DIR/issue-78192.rs:+1:24: +1:40
-      let _4: *const T;                    // in scope 0 at $DIR/issue-78192.rs:+1:25: +1:40
+      debug a => _1;                       // in scope 0 at $DIR/issue_78192.rs:+0:13: +0:14
+      let mut _0: *const T;                // return place in scope 0 at $DIR/issue_78192.rs:+0:23: +0:31
+      let _2: &*const T;                   // in scope 0 at $DIR/issue_78192.rs:+1:9: +1:10
+      let _3: &*const T;                   // in scope 0 at $DIR/issue_78192.rs:+1:24: +1:40
+      let _4: *const T;                    // in scope 0 at $DIR/issue_78192.rs:+1:25: +1:40
       scope 1 {
-          debug b => _2;                   // in scope 1 at $DIR/issue-78192.rs:+1:9: +1:10
+          debug b => _2;                   // in scope 1 at $DIR/issue_78192.rs:+1:9: +1:10
       }
   
       bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/issue-78192.rs:+1:9: +1:10
-          StorageLive(_3);                 // scope 0 at $DIR/issue-78192.rs:+1:24: +1:40
-          StorageLive(_4);                 // scope 0 at $DIR/issue-78192.rs:+1:25: +1:40
-          _4 = &raw const (*_1);           // scope 0 at $DIR/issue-78192.rs:+1:26: +1:27
-          _3 = &_4;                        // scope 0 at $DIR/issue-78192.rs:+1:24: +1:40
--         _2 = &(*_3);                     // scope 0 at $DIR/issue-78192.rs:+1:24: +1:40
-+         _2 = _3;                         // scope 0 at $DIR/issue-78192.rs:+1:24: +1:40
-          StorageDead(_3);                 // scope 0 at $DIR/issue-78192.rs:+1:40: +1:41
-          _0 = (*_2);                      // scope 1 at $DIR/issue-78192.rs:+2:5: +2:7
-          StorageDead(_4);                 // scope 0 at $DIR/issue-78192.rs:+3:1: +3:2
-          StorageDead(_2);                 // scope 0 at $DIR/issue-78192.rs:+3:1: +3:2
-          return;                          // scope 0 at $DIR/issue-78192.rs:+3:2: +3:2
+          StorageLive(_2);                 // scope 0 at $DIR/issue_78192.rs:+1:9: +1:10
+          StorageLive(_3);                 // scope 0 at $DIR/issue_78192.rs:+1:24: +1:40
+          StorageLive(_4);                 // scope 0 at $DIR/issue_78192.rs:+1:25: +1:40
+          _4 = &raw const (*_1);           // scope 0 at $DIR/issue_78192.rs:+1:26: +1:27
+          _3 = &_4;                        // scope 0 at $DIR/issue_78192.rs:+1:24: +1:40
+-         _2 = &(*_3);                     // scope 0 at $DIR/issue_78192.rs:+1:24: +1:40
++         _2 = _3;                         // scope 0 at $DIR/issue_78192.rs:+1:24: +1:40
+          StorageDead(_3);                 // scope 0 at $DIR/issue_78192.rs:+1:40: +1:41
+          _0 = (*_2);                      // scope 1 at $DIR/issue_78192.rs:+2:5: +2:7
+          StorageDead(_4);                 // scope 0 at $DIR/issue_78192.rs:+3:1: +3:2
+          StorageDead(_2);                 // scope 0 at $DIR/issue_78192.rs:+3:1: +3:2
+          return;                          // scope 0 at $DIR/issue_78192.rs:+3:2: +3:2
       }
   }
   
diff --git a/src/test/mir-opt/issue-78192.rs b/src/test/mir-opt/issue_78192.rs
similarity index 100%
rename from src/test/mir-opt/issue-78192.rs
rename to src/test/mir-opt/issue_78192.rs
diff --git a/src/test/mir-opt/issue_91633.bar.mir_map.0.mir b/src/test/mir-opt/issue_91633.bar.built.after.mir
similarity index 72%
rename from src/test/mir-opt/issue_91633.bar.mir_map.0.mir
rename to src/test/mir-opt/issue_91633.bar.built.after.mir
index 625f6c7361ac..c3fb90e84024 100644
--- a/src/test/mir-opt/issue_91633.bar.mir_map.0.mir
+++ b/src/test/mir-opt/issue_91633.bar.built.after.mir
@@ -1,39 +1,39 @@
-// MIR for `bar` 0 mir_map
+// MIR for `bar` after built
 
 fn bar(_1: Box<[T]>) -> () {
-    debug it => _1;                      // in scope 0 at $DIR/issue-91633.rs:+0:12: +0:14
-    let mut _0: ();                      // return place in scope 0 at $DIR/issue-91633.rs:+1:2: +1:2
-    let mut _2: &<[T] as std::ops::Index<usize>>::Output; // in scope 0 at $DIR/issue-91633.rs:+4:14: +4:19
-    let mut _3: &[T];                    // in scope 0 at $DIR/issue-91633.rs:+4:14: +4:16
+    debug it => _1;                      // in scope 0 at $DIR/issue_91633.rs:+0:12: +0:14
+    let mut _0: ();                      // return place in scope 0 at $DIR/issue_91633.rs:+1:2: +1:2
+    let mut _2: &<[T] as std::ops::Index<usize>>::Output; // in scope 0 at $DIR/issue_91633.rs:+4:14: +4:19
+    let mut _3: &[T];                    // in scope 0 at $DIR/issue_91633.rs:+4:14: +4:16
     scope 1 {
     }
 
     bb0: {
-        StorageLive(_2);                 // scope 0 at $DIR/issue-91633.rs:+4:14: +4:19
-        StorageLive(_3);                 // scope 0 at $DIR/issue-91633.rs:+4:14: +4:16
-        _3 = &(*_1);                     // scope 0 at $DIR/issue-91633.rs:+4:14: +4:16
-        _2 = <[T] as Index<usize>>::index(move _3, const 0_usize) -> [return: bb1, unwind: bb3]; // scope 0 at $DIR/issue-91633.rs:+4:14: +4:19
+        StorageLive(_2);                 // scope 0 at $DIR/issue_91633.rs:+4:14: +4:19
+        StorageLive(_3);                 // scope 0 at $DIR/issue_91633.rs:+4:14: +4:16
+        _3 = &(*_1);                     // scope 0 at $DIR/issue_91633.rs:+4:14: +4:16
+        _2 = <[T] as Index<usize>>::index(move _3, const 0_usize) -> [return: bb1, unwind: bb3]; // scope 0 at $DIR/issue_91633.rs:+4:14: +4:19
                                          // mir::Constant
-                                         // + span: $DIR/issue-91633.rs:15:14: 15:19
+                                         // + span: $DIR/issue_91633.rs:15:14: 15:19
                                          // + literal: Const { ty: for<'a> fn(&'a [T], usize) -> &'a <[T] as Index<usize>>::Output {<[T] as Index<usize>>::index}, val: Value(<ZST>) }
     }
 
     bb1: {
-        StorageDead(_3);                 // scope 0 at $DIR/issue-91633.rs:+4:18: +4:19
-        StorageDead(_2);                 // scope 0 at $DIR/issue-91633.rs:+4:19: +4:20
-        _0 = const ();                   // scope 0 at $DIR/issue-91633.rs:+3:2: +5:3
-        drop(_1) -> [return: bb2, unwind: bb4]; // scope 0 at $DIR/issue-91633.rs:+5:2: +5:3
+        StorageDead(_3);                 // scope 0 at $DIR/issue_91633.rs:+4:18: +4:19
+        StorageDead(_2);                 // scope 0 at $DIR/issue_91633.rs:+4:19: +4:20
+        _0 = const ();                   // scope 0 at $DIR/issue_91633.rs:+3:2: +5:3
+        drop(_1) -> [return: bb2, unwind: bb4]; // scope 0 at $DIR/issue_91633.rs:+5:2: +5:3
     }
 
     bb2: {
-        return;                          // scope 0 at $DIR/issue-91633.rs:+5:3: +5:3
+        return;                          // scope 0 at $DIR/issue_91633.rs:+5:3: +5:3
     }
 
     bb3 (cleanup): {
-        drop(_1) -> bb4;                 // scope 0 at $DIR/issue-91633.rs:+5:2: +5:3
+        drop(_1) -> bb4;                 // scope 0 at $DIR/issue_91633.rs:+5:2: +5:3
     }
 
     bb4 (cleanup): {
-        resume;                          // scope 0 at $DIR/issue-91633.rs:+0:1: +5:3
+        resume;                          // scope 0 at $DIR/issue_91633.rs:+0:1: +5:3
     }
 }
diff --git a/src/test/mir-opt/issue_91633.foo.mir_map.0.mir b/src/test/mir-opt/issue_91633.foo.built.after.mir
similarity index 72%
rename from src/test/mir-opt/issue_91633.foo.mir_map.0.mir
rename to src/test/mir-opt/issue_91633.foo.built.after.mir
index 9903e203a231..4e3dd365e924 100644
--- a/src/test/mir-opt/issue_91633.foo.mir_map.0.mir
+++ b/src/test/mir-opt/issue_91633.foo.built.after.mir
@@ -1,57 +1,57 @@
-// MIR for `foo` 0 mir_map
+// MIR for `foo` after built
 
 fn foo(_1: Box<[T]>) -> T {
-    debug it => _1;                      // in scope 0 at $DIR/issue-91633.rs:+0:19: +0:21
-    let mut _0: T;                       // return place in scope 0 at $DIR/issue-91633.rs:+0:36: +0:37
-    let _2: T;                           // in scope 0 at $DIR/issue-91633.rs:+2:10: +2:11
-    let mut _3: &T;                      // in scope 0 at $DIR/issue-91633.rs:+2:14: +2:27
-    let _4: usize;                       // in scope 0 at $DIR/issue-91633.rs:+2:17: +2:18
-    let mut _5: usize;                   // in scope 0 at $DIR/issue-91633.rs:+2:14: +2:19
-    let mut _6: bool;                    // in scope 0 at $DIR/issue-91633.rs:+2:14: +2:19
+    debug it => _1;                      // in scope 0 at $DIR/issue_91633.rs:+0:19: +0:21
+    let mut _0: T;                       // return place in scope 0 at $DIR/issue_91633.rs:+0:36: +0:37
+    let _2: T;                           // in scope 0 at $DIR/issue_91633.rs:+2:10: +2:11
+    let mut _3: &T;                      // in scope 0 at $DIR/issue_91633.rs:+2:14: +2:27
+    let _4: usize;                       // in scope 0 at $DIR/issue_91633.rs:+2:17: +2:18
+    let mut _5: usize;                   // in scope 0 at $DIR/issue_91633.rs:+2:14: +2:19
+    let mut _6: bool;                    // in scope 0 at $DIR/issue_91633.rs:+2:14: +2:19
     scope 1 {
-        debug f => _2;                   // in scope 1 at $DIR/issue-91633.rs:+2:10: +2:11
+        debug f => _2;                   // in scope 1 at $DIR/issue_91633.rs:+2:10: +2:11
     }
 
     bb0: {
-        StorageLive(_2);                 // scope 0 at $DIR/issue-91633.rs:+2:10: +2:11
-        StorageLive(_3);                 // scope 0 at $DIR/issue-91633.rs:+2:14: +2:27
-        StorageLive(_4);                 // scope 0 at $DIR/issue-91633.rs:+2:17: +2:18
-        _4 = const 0_usize;              // scope 0 at $DIR/issue-91633.rs:+2:17: +2:18
-        _5 = Len((*_1));                 // scope 0 at $DIR/issue-91633.rs:+2:14: +2:19
-        _6 = Lt(_4, _5);                 // scope 0 at $DIR/issue-91633.rs:+2:14: +2:19
-        assert(move _6, "index out of bounds: the length is {} but the index is {}", move _5, _4) -> [success: bb1, unwind: bb5]; // scope 0 at $DIR/issue-91633.rs:+2:14: +2:19
+        StorageLive(_2);                 // scope 0 at $DIR/issue_91633.rs:+2:10: +2:11
+        StorageLive(_3);                 // scope 0 at $DIR/issue_91633.rs:+2:14: +2:27
+        StorageLive(_4);                 // scope 0 at $DIR/issue_91633.rs:+2:17: +2:18
+        _4 = const 0_usize;              // scope 0 at $DIR/issue_91633.rs:+2:17: +2:18
+        _5 = Len((*_1));                 // scope 0 at $DIR/issue_91633.rs:+2:14: +2:19
+        _6 = Lt(_4, _5);                 // scope 0 at $DIR/issue_91633.rs:+2:14: +2:19
+        assert(move _6, "index out of bounds: the length is {} but the index is {}", move _5, _4) -> [success: bb1, unwind: bb5]; // scope 0 at $DIR/issue_91633.rs:+2:14: +2:19
     }
 
     bb1: {
-        _3 = &(*_1)[_4];                 // scope 0 at $DIR/issue-91633.rs:+2:14: +2:27
-        _2 = <T as Clone>::clone(move _3) -> [return: bb2, unwind: bb5]; // scope 0 at $DIR/issue-91633.rs:+2:14: +2:27
+        _3 = &(*_1)[_4];                 // scope 0 at $DIR/issue_91633.rs:+2:14: +2:27
+        _2 = <T as Clone>::clone(move _3) -> [return: bb2, unwind: bb5]; // scope 0 at $DIR/issue_91633.rs:+2:14: +2:27
                                          // mir::Constant
-                                         // + span: $DIR/issue-91633.rs:28:20: 28:25
+                                         // + span: $DIR/issue_91633.rs:28:20: 28:25
                                          // + literal: Const { ty: for<'a> fn(&'a T) -> T {<T as Clone>::clone}, val: Value(<ZST>) }
     }
 
     bb2: {
-        StorageDead(_3);                 // scope 0 at $DIR/issue-91633.rs:+2:26: +2:27
-        FakeRead(ForLet(None), _2);      // scope 0 at $DIR/issue-91633.rs:+2:10: +2:11
-        StorageDead(_4);                 // scope 0 at $DIR/issue-91633.rs:+2:27: +2:28
-        _0 = move _2;                    // scope 1 at $DIR/issue-91633.rs:+3:6: +3:7
-        drop(_2) -> [return: bb3, unwind: bb5]; // scope 0 at $DIR/issue-91633.rs:+4:2: +4:3
+        StorageDead(_3);                 // scope 0 at $DIR/issue_91633.rs:+2:26: +2:27
+        FakeRead(ForLet(None), _2);      // scope 0 at $DIR/issue_91633.rs:+2:10: +2:11
+        StorageDead(_4);                 // scope 0 at $DIR/issue_91633.rs:+2:27: +2:28
+        _0 = move _2;                    // scope 1 at $DIR/issue_91633.rs:+3:6: +3:7
+        drop(_2) -> [return: bb3, unwind: bb5]; // scope 0 at $DIR/issue_91633.rs:+4:2: +4:3
     }
 
     bb3: {
-        StorageDead(_2);                 // scope 0 at $DIR/issue-91633.rs:+4:2: +4:3
-        drop(_1) -> [return: bb4, unwind: bb6]; // scope 0 at $DIR/issue-91633.rs:+4:2: +4:3
+        StorageDead(_2);                 // scope 0 at $DIR/issue_91633.rs:+4:2: +4:3
+        drop(_1) -> [return: bb4, unwind: bb6]; // scope 0 at $DIR/issue_91633.rs:+4:2: +4:3
     }
 
     bb4: {
-        return;                          // scope 0 at $DIR/issue-91633.rs:+4:3: +4:3
+        return;                          // scope 0 at $DIR/issue_91633.rs:+4:3: +4:3
     }
 
     bb5 (cleanup): {
-        drop(_1) -> bb6;                 // scope 0 at $DIR/issue-91633.rs:+4:2: +4:3
+        drop(_1) -> bb6;                 // scope 0 at $DIR/issue_91633.rs:+4:2: +4:3
     }
 
     bb6 (cleanup): {
-        resume;                          // scope 0 at $DIR/issue-91633.rs:+0:1: +4:3
+        resume;                          // scope 0 at $DIR/issue_91633.rs:+0:1: +4:3
     }
 }
diff --git a/src/test/mir-opt/issue_91633.fun.mir_map.0.mir b/src/test/mir-opt/issue_91633.fun.built.after.mir
similarity index 72%
rename from src/test/mir-opt/issue_91633.fun.mir_map.0.mir
rename to src/test/mir-opt/issue_91633.fun.built.after.mir
index ded9a4cf7e3f..42486d3a50e3 100644
--- a/src/test/mir-opt/issue_91633.fun.mir_map.0.mir
+++ b/src/test/mir-opt/issue_91633.fun.built.after.mir
@@ -1,35 +1,35 @@
-// MIR for `fun` 0 mir_map
+// MIR for `fun` after built
 
 fn fun(_1: &[T]) -> &T {
-    debug it => _1;                      // in scope 0 at $DIR/issue-91633.rs:+0:12: +0:14
-    let mut _0: &T;                      // return place in scope 0 at $DIR/issue-91633.rs:+0:25: +0:27
-    let _2: &T;                          // in scope 0 at $DIR/issue-91633.rs:+2:10: +2:11
-    let _3: usize;                       // in scope 0 at $DIR/issue-91633.rs:+2:18: +2:19
-    let mut _4: usize;                   // in scope 0 at $DIR/issue-91633.rs:+2:15: +2:20
-    let mut _5: bool;                    // in scope 0 at $DIR/issue-91633.rs:+2:15: +2:20
+    debug it => _1;                      // in scope 0 at $DIR/issue_91633.rs:+0:12: +0:14
+    let mut _0: &T;                      // return place in scope 0 at $DIR/issue_91633.rs:+0:25: +0:27
+    let _2: &T;                          // in scope 0 at $DIR/issue_91633.rs:+2:10: +2:11
+    let _3: usize;                       // in scope 0 at $DIR/issue_91633.rs:+2:18: +2:19
+    let mut _4: usize;                   // in scope 0 at $DIR/issue_91633.rs:+2:15: +2:20
+    let mut _5: bool;                    // in scope 0 at $DIR/issue_91633.rs:+2:15: +2:20
     scope 1 {
-        debug f => _2;                   // in scope 1 at $DIR/issue-91633.rs:+2:10: +2:11
+        debug f => _2;                   // in scope 1 at $DIR/issue_91633.rs:+2:10: +2:11
     }
 
     bb0: {
-        StorageLive(_2);                 // scope 0 at $DIR/issue-91633.rs:+2:10: +2:11
-        StorageLive(_3);                 // scope 0 at $DIR/issue-91633.rs:+2:18: +2:19
-        _3 = const 0_usize;              // scope 0 at $DIR/issue-91633.rs:+2:18: +2:19
-        _4 = Len((*_1));                 // scope 0 at $DIR/issue-91633.rs:+2:15: +2:20
-        _5 = Lt(_3, _4);                 // scope 0 at $DIR/issue-91633.rs:+2:15: +2:20
-        assert(move _5, "index out of bounds: the length is {} but the index is {}", move _4, _3) -> [success: bb1, unwind: bb2]; // scope 0 at $DIR/issue-91633.rs:+2:15: +2:20
+        StorageLive(_2);                 // scope 0 at $DIR/issue_91633.rs:+2:10: +2:11
+        StorageLive(_3);                 // scope 0 at $DIR/issue_91633.rs:+2:18: +2:19
+        _3 = const 0_usize;              // scope 0 at $DIR/issue_91633.rs:+2:18: +2:19
+        _4 = Len((*_1));                 // scope 0 at $DIR/issue_91633.rs:+2:15: +2:20
+        _5 = Lt(_3, _4);                 // scope 0 at $DIR/issue_91633.rs:+2:15: +2:20
+        assert(move _5, "index out of bounds: the length is {} but the index is {}", move _4, _3) -> [success: bb1, unwind: bb2]; // scope 0 at $DIR/issue_91633.rs:+2:15: +2:20
     }
 
     bb1: {
-        _2 = &(*_1)[_3];                 // scope 0 at $DIR/issue-91633.rs:+2:14: +2:20
-        FakeRead(ForLet(None), _2);      // scope 0 at $DIR/issue-91633.rs:+2:10: +2:11
-        _0 = &(*_2);                     // scope 1 at $DIR/issue-91633.rs:+3:6: +3:7
-        StorageDead(_3);                 // scope 0 at $DIR/issue-91633.rs:+4:2: +4:3
-        StorageDead(_2);                 // scope 0 at $DIR/issue-91633.rs:+4:2: +4:3
-        return;                          // scope 0 at $DIR/issue-91633.rs:+4:3: +4:3
+        _2 = &(*_1)[_3];                 // scope 0 at $DIR/issue_91633.rs:+2:14: +2:20
+        FakeRead(ForLet(None), _2);      // scope 0 at $DIR/issue_91633.rs:+2:10: +2:11
+        _0 = &(*_2);                     // scope 1 at $DIR/issue_91633.rs:+3:6: +3:7
+        StorageDead(_3);                 // scope 0 at $DIR/issue_91633.rs:+4:2: +4:3
+        StorageDead(_2);                 // scope 0 at $DIR/issue_91633.rs:+4:2: +4:3
+        return;                          // scope 0 at $DIR/issue_91633.rs:+4:3: +4:3
     }
 
     bb2 (cleanup): {
-        resume;                          // scope 0 at $DIR/issue-91633.rs:+0:1: +4:3
+        resume;                          // scope 0 at $DIR/issue_91633.rs:+0:1: +4:3
     }
 }
diff --git a/src/test/mir-opt/issue_91633.hey.mir_map.0.mir b/src/test/mir-opt/issue_91633.hey.built.after.mir
similarity index 71%
rename from src/test/mir-opt/issue_91633.hey.mir_map.0.mir
rename to src/test/mir-opt/issue_91633.hey.built.after.mir
index 37c3b3fcacaf..ccb06dd5983f 100644
--- a/src/test/mir-opt/issue_91633.hey.mir_map.0.mir
+++ b/src/test/mir-opt/issue_91633.hey.built.after.mir
@@ -1,35 +1,35 @@
-// MIR for `hey` 0 mir_map
+// MIR for `hey` after built
 
 fn hey(_1: &[T]) -> () {
-    debug it => _1;                      // in scope 0 at $DIR/issue-91633.rs:+0:12: +0:14
-    let mut _0: ();                      // return place in scope 0 at $DIR/issue-91633.rs:+1:2: +1:2
-    let mut _2: &<[T] as std::ops::Index<usize>>::Output; // in scope 0 at $DIR/issue-91633.rs:+4:14: +4:20
-    let _3: &<[T] as std::ops::Index<usize>>::Output; // in scope 0 at $DIR/issue-91633.rs:+4:15: +4:20
-    let mut _4: &[T];                    // in scope 0 at $DIR/issue-91633.rs:+4:15: +4:17
+    debug it => _1;                      // in scope 0 at $DIR/issue_91633.rs:+0:12: +0:14
+    let mut _0: ();                      // return place in scope 0 at $DIR/issue_91633.rs:+1:2: +1:2
+    let mut _2: &<[T] as std::ops::Index<usize>>::Output; // in scope 0 at $DIR/issue_91633.rs:+4:14: +4:20
+    let _3: &<[T] as std::ops::Index<usize>>::Output; // in scope 0 at $DIR/issue_91633.rs:+4:15: +4:20
+    let mut _4: &[T];                    // in scope 0 at $DIR/issue_91633.rs:+4:15: +4:17
     scope 1 {
     }
 
     bb0: {
-        StorageLive(_2);                 // scope 0 at $DIR/issue-91633.rs:+4:14: +4:20
-        StorageLive(_3);                 // scope 0 at $DIR/issue-91633.rs:+4:15: +4:20
-        StorageLive(_4);                 // scope 0 at $DIR/issue-91633.rs:+4:15: +4:17
-        _4 = &(*_1);                     // scope 0 at $DIR/issue-91633.rs:+4:15: +4:17
-        _3 = <[T] as Index<usize>>::index(move _4, const 0_usize) -> [return: bb1, unwind: bb2]; // scope 0 at $DIR/issue-91633.rs:+4:15: +4:20
+        StorageLive(_2);                 // scope 0 at $DIR/issue_91633.rs:+4:14: +4:20
+        StorageLive(_3);                 // scope 0 at $DIR/issue_91633.rs:+4:15: +4:20
+        StorageLive(_4);                 // scope 0 at $DIR/issue_91633.rs:+4:15: +4:17
+        _4 = &(*_1);                     // scope 0 at $DIR/issue_91633.rs:+4:15: +4:17
+        _3 = <[T] as Index<usize>>::index(move _4, const 0_usize) -> [return: bb1, unwind: bb2]; // scope 0 at $DIR/issue_91633.rs:+4:15: +4:20
                                          // mir::Constant
-                                         // + span: $DIR/issue-91633.rs:7:15: 7:20
+                                         // + span: $DIR/issue_91633.rs:7:15: 7:20
                                          // + literal: Const { ty: for<'a> fn(&'a [T], usize) -> &'a <[T] as Index<usize>>::Output {<[T] as Index<usize>>::index}, val: Value(<ZST>) }
     }
 
     bb1: {
-        StorageDead(_4);                 // scope 0 at $DIR/issue-91633.rs:+4:19: +4:20
-        _2 = &(*_3);                     // scope 0 at $DIR/issue-91633.rs:+4:14: +4:20
-        StorageDead(_2);                 // scope 0 at $DIR/issue-91633.rs:+4:20: +4:21
-        _0 = const ();                   // scope 0 at $DIR/issue-91633.rs:+3:2: +5:3
-        StorageDead(_3);                 // scope 0 at $DIR/issue-91633.rs:+5:2: +5:3
-        return;                          // scope 0 at $DIR/issue-91633.rs:+5:3: +5:3
+        StorageDead(_4);                 // scope 0 at $DIR/issue_91633.rs:+4:19: +4:20
+        _2 = &(*_3);                     // scope 0 at $DIR/issue_91633.rs:+4:14: +4:20
+        StorageDead(_2);                 // scope 0 at $DIR/issue_91633.rs:+4:20: +4:21
+        _0 = const ();                   // scope 0 at $DIR/issue_91633.rs:+3:2: +5:3
+        StorageDead(_3);                 // scope 0 at $DIR/issue_91633.rs:+5:2: +5:3
+        return;                          // scope 0 at $DIR/issue_91633.rs:+5:3: +5:3
     }
 
     bb2 (cleanup): {
-        resume;                          // scope 0 at $DIR/issue-91633.rs:+0:1: +5:3
+        resume;                          // scope 0 at $DIR/issue_91633.rs:+0:1: +5:3
     }
 }
diff --git a/src/test/mir-opt/issue-91633.rs b/src/test/mir-opt/issue_91633.rs
similarity index 68%
rename from src/test/mir-opt/issue-91633.rs
rename to src/test/mir-opt/issue_91633.rs
index 8f66019857fb..9127cacc97c5 100644
--- a/src/test/mir-opt/issue-91633.rs
+++ b/src/test/mir-opt/issue_91633.rs
@@ -1,5 +1,5 @@
 // compile-flags: -Z mir-opt-level=0
-// EMIT_MIR issue_91633.hey.mir_map.0.mir
+// EMIT_MIR issue_91633.hey.built.after.mir
 fn hey<T> (it: &[T])
  where
      [T] : std::ops::Index<usize>,
@@ -7,7 +7,7 @@ fn hey<T> (it: &[T])
      let _ = &it[0];
  }
 
-// EMIT_MIR issue_91633.bar.mir_map.0.mir
+// EMIT_MIR issue_91633.bar.built.after.mir
 fn bar<T> (it: Box<[T]>)
  where
      [T] : std::ops::Index<usize>,
@@ -15,14 +15,14 @@ fn bar<T> (it: Box<[T]>)
      let _ = it[0];
  }
 
-// EMIT_MIR issue_91633.fun.mir_map.0.mir
+// EMIT_MIR issue_91633.fun.built.after.mir
 fn fun<T> (it: &[T]) -> &T
  {
      let f = &it[0];
      f
  }
 
-// EMIT_MIR issue_91633.foo.mir_map.0.mir
+// EMIT_MIR issue_91633.foo.built.after.mir
 fn foo<T: Clone> (it: Box<[T]>) -> T
  {
      let f = it[0].clone();
diff --git a/src/test/mir-opt/issue_99325.main.mir_map.0.mir b/src/test/mir-opt/issue_99325.main.built.after.mir
similarity index 95%
rename from src/test/mir-opt/issue_99325.main.mir_map.0.mir
rename to src/test/mir-opt/issue_99325.main.built.after.mir
index 165efa9df411..3db40412b2ef 100644
--- a/src/test/mir-opt/issue_99325.main.mir_map.0.mir
+++ b/src/test/mir-opt/issue_99325.main.built.after.mir
@@ -1,18 +1,18 @@
-// MIR for `main` 0 mir_map
+// MIR for `main` after built
 
 | User Type Annotations
-| 0: user_ty: Canonical { max_universe: U0, variables: [], value: TypeOf(DefId(0:3 ~ issue_99325[8f58]::function_with_bytes), UserSubsts { substs: [Const { ty: &'static [u8; 4], kind: Value(Branch([Leaf(0x41), Leaf(0x41), Leaf(0x41), Leaf(0x41)])) }], user_self_ty: None }) }, span: $DIR/issue-99325.rs:10:16: 10:46, inferred_ty: fn() -> &'static [u8] {function_with_bytes::<&*b"AAAA">}
-| 1: user_ty: Canonical { max_universe: U0, variables: [], value: TypeOf(DefId(0:3 ~ issue_99325[8f58]::function_with_bytes), UserSubsts { substs: [Const { ty: &'static [u8; 4], kind: Unevaluated(UnevaluatedConst { def: WithOptConstParam { did: DefId(0:8 ~ issue_99325[8f58]::main::{constant#1}), const_param_did: Some(DefId(0:4 ~ issue_99325[8f58]::function_with_bytes::BYTES)) }, substs: [] }) }], user_self_ty: None }) }, span: $DIR/issue-99325.rs:11:16: 11:68, inferred_ty: fn() -> &'static [u8] {function_with_bytes::<&*b"AAAA">}
+| 0: user_ty: Canonical { max_universe: U0, variables: [], value: TypeOf(DefId(0:3 ~ issue_99325[8f58]::function_with_bytes), UserSubsts { substs: [Const { ty: &'static [u8; 4], kind: Value(Branch([Leaf(0x41), Leaf(0x41), Leaf(0x41), Leaf(0x41)])) }], user_self_ty: None }) }, span: $DIR/issue_99325.rs:10:16: 10:46, inferred_ty: fn() -> &'static [u8] {function_with_bytes::<&*b"AAAA">}
+| 1: user_ty: Canonical { max_universe: U0, variables: [], value: TypeOf(DefId(0:3 ~ issue_99325[8f58]::function_with_bytes), UserSubsts { substs: [Const { ty: &'static [u8; 4], kind: Unevaluated(UnevaluatedConst { def: WithOptConstParam { did: DefId(0:8 ~ issue_99325[8f58]::main::{constant#1}), const_param_did: Some(DefId(0:4 ~ issue_99325[8f58]::function_with_bytes::BYTES)) }, substs: [] }) }], user_self_ty: None }) }, span: $DIR/issue_99325.rs:11:16: 11:68, inferred_ty: fn() -> &'static [u8] {function_with_bytes::<&*b"AAAA">}
 |
 fn main() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/issue-99325.rs:+0:15: +0:15
+    let mut _0: ();                      // return place in scope 0 at $DIR/issue_99325.rs:+0:15: +0:15
     let _1: ();                          // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     let mut _2: (&&[u8], &&[u8; 4]);     // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     let mut _3: &&[u8];                  // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-    let _4: &[u8];                       // in scope 0 at $DIR/issue-99325.rs:+1:16: +1:48
+    let _4: &[u8];                       // in scope 0 at $DIR/issue_99325.rs:+1:16: +1:48
     let mut _5: &&[u8; 4];               // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-    let _6: &[u8; 4];                    // in scope 0 at $DIR/issue-99325.rs:+1:50: +1:75
-    let _7: [u8; 4];                     // in scope 0 at $DIR/issue-99325.rs:+1:51: +1:75
+    let _6: &[u8; 4];                    // in scope 0 at $DIR/issue_99325.rs:+1:50: +1:75
+    let _7: [u8; 4];                     // in scope 0 at $DIR/issue_99325.rs:+1:51: +1:75
     let _8: &&[u8];                      // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     let _9: &&[u8; 4];                   // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     let mut _10: bool;                   // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
@@ -30,9 +30,9 @@ fn main() -> () {
     let _23: ();                         // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     let mut _24: (&&[u8], &&[u8; 4]);    // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     let mut _25: &&[u8];                 // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-    let _26: &[u8];                      // in scope 0 at $DIR/issue-99325.rs:+2:16: +2:70
+    let _26: &[u8];                      // in scope 0 at $DIR/issue_99325.rs:+2:16: +2:70
     let mut _27: &&[u8; 4];              // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-    let _28: &[u8; 4];                   // in scope 0 at $DIR/issue-99325.rs:+2:72: +2:79
+    let _28: &[u8; 4];                   // in scope 0 at $DIR/issue_99325.rs:+2:72: +2:79
     let _29: &&[u8];                     // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     let _30: &&[u8; 4];                  // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     let mut _31: bool;                   // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
@@ -68,10 +68,10 @@ fn main() -> () {
         StorageLive(_1);                 // scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageLive(_2);                 // scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageLive(_3);                 // scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-        StorageLive(_4);                 // scope 0 at $DIR/issue-99325.rs:+1:16: +1:48
-        _4 = function_with_bytes::<&*b"AAAA">() -> [return: bb1, unwind: bb19]; // scope 0 at $DIR/issue-99325.rs:+1:16: +1:48
+        StorageLive(_4);                 // scope 0 at $DIR/issue_99325.rs:+1:16: +1:48
+        _4 = function_with_bytes::<&*b"AAAA">() -> [return: bb1, unwind: bb19]; // scope 0 at $DIR/issue_99325.rs:+1:16: +1:48
                                          // mir::Constant
-                                         // + span: $DIR/issue-99325.rs:10:16: 10:46
+                                         // + span: $DIR/issue_99325.rs:10:16: 10:46
                                          // + user_ty: UserType(0)
                                          // + literal: Const { ty: fn() -> &'static [u8] {function_with_bytes::<&*b"AAAA">}, val: Value(<ZST>) }
     }
@@ -79,10 +79,10 @@ fn main() -> () {
     bb1: {
         _3 = &_4;                        // scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageLive(_5);                 // scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-        StorageLive(_6);                 // scope 0 at $DIR/issue-99325.rs:+1:50: +1:75
-        StorageLive(_7);                 // scope 0 at $DIR/issue-99325.rs:+1:51: +1:75
-        _7 = [const 65_u8, const 65_u8, const 65_u8, const 65_u8]; // scope 0 at $DIR/issue-99325.rs:+1:51: +1:75
-        _6 = &_7;                        // scope 0 at $DIR/issue-99325.rs:+1:50: +1:75
+        StorageLive(_6);                 // scope 0 at $DIR/issue_99325.rs:+1:50: +1:75
+        StorageLive(_7);                 // scope 0 at $DIR/issue_99325.rs:+1:51: +1:75
+        _7 = [const 65_u8, const 65_u8, const 65_u8, const 65_u8]; // scope 0 at $DIR/issue_99325.rs:+1:51: +1:75
+        _6 = &_7;                        // scope 0 at $DIR/issue_99325.rs:+1:50: +1:75
         _5 = &_6;                        // scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         _2 = (move _3, move _5);         // scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageDead(_5);                 // scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
@@ -176,10 +176,10 @@ fn main() -> () {
         StorageLive(_23);                // scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageLive(_24);                // scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageLive(_25);                // scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-        StorageLive(_26);                // scope 0 at $DIR/issue-99325.rs:+2:16: +2:70
-        _26 = function_with_bytes::<&*b"AAAA">() -> [return: bb10, unwind: bb19]; // scope 0 at $DIR/issue-99325.rs:+2:16: +2:70
+        StorageLive(_26);                // scope 0 at $DIR/issue_99325.rs:+2:16: +2:70
+        _26 = function_with_bytes::<&*b"AAAA">() -> [return: bb10, unwind: bb19]; // scope 0 at $DIR/issue_99325.rs:+2:16: +2:70
                                          // mir::Constant
-                                         // + span: $DIR/issue-99325.rs:11:16: 11:68
+                                         // + span: $DIR/issue_99325.rs:11:16: 11:68
                                          // + user_ty: UserType(1)
                                          // + literal: Const { ty: fn() -> &'static [u8] {function_with_bytes::<&*b"AAAA">}, val: Value(<ZST>) }
     }
@@ -187,10 +187,10 @@ fn main() -> () {
     bb10: {
         _25 = &_26;                      // scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageLive(_27);                // scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-        StorageLive(_28);                // scope 0 at $DIR/issue-99325.rs:+2:72: +2:79
-        _28 = const b"AAAA";             // scope 0 at $DIR/issue-99325.rs:+2:72: +2:79
+        StorageLive(_28);                // scope 0 at $DIR/issue_99325.rs:+2:72: +2:79
+        _28 = const b"AAAA";             // scope 0 at $DIR/issue_99325.rs:+2:72: +2:79
                                          // mir::Constant
-                                         // + span: $DIR/issue-99325.rs:11:72: 11:79
+                                         // + span: $DIR/issue_99325.rs:11:72: 11:79
                                          // + literal: Const { ty: &[u8; 4], val: Value(Scalar(alloc4)) }
         _27 = &_28;                      // scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         _24 = (move _25, move _27);      // scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
@@ -281,12 +281,12 @@ fn main() -> () {
         StorageDead(_26);                // scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageDead(_24);                // scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageDead(_23);                // scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-        _0 = const ();                   // scope 0 at $DIR/issue-99325.rs:+0:15: +3:2
-        return;                          // scope 0 at $DIR/issue-99325.rs:+3:2: +3:2
+        _0 = const ();                   // scope 0 at $DIR/issue_99325.rs:+0:15: +3:2
+        return;                          // scope 0 at $DIR/issue_99325.rs:+3:2: +3:2
     }
 
     bb19 (cleanup): {
-        resume;                          // scope 0 at $DIR/issue-99325.rs:+0:1: +3:2
+        resume;                          // scope 0 at $DIR/issue_99325.rs:+0:1: +3:2
     }
 }
 
diff --git a/src/test/mir-opt/issue-99325.rs b/src/test/mir-opt/issue_99325.rs
similarity index 88%
rename from src/test/mir-opt/issue-99325.rs
rename to src/test/mir-opt/issue_99325.rs
index b79946ea8b56..fe819cddb2c3 100644
--- a/src/test/mir-opt/issue-99325.rs
+++ b/src/test/mir-opt/issue_99325.rs
@@ -5,7 +5,7 @@ pub fn function_with_bytes<const BYTES: &'static [u8; 4]>() -> &'static [u8] {
     BYTES
 }
 
-// EMIT_MIR issue_99325.main.mir_map.0.mir
+// EMIT_MIR issue_99325.main.built.after.mir
 pub fn main() {
     assert_eq!(function_with_bytes::<b"AAAA">(), &[0x41, 0x41, 0x41, 0x41]);
     assert_eq!(function_with_bytes::<{ &[0x41, 0x41, 0x41, 0x41] }>(), b"AAAA");
diff --git a/src/test/mir-opt/issues/issue_59352.num_to_digit.PreCodegen.after.mir b/src/test/mir-opt/issues/issue_59352.num_to_digit.PreCodegen.after.mir
index f46c10711f68..1cfa41b4daa4 100644
--- a/src/test/mir-opt/issues/issue_59352.num_to_digit.PreCodegen.after.mir
+++ b/src/test/mir-opt/issues/issue_59352.num_to_digit.PreCodegen.after.mir
@@ -1,14 +1,14 @@
 // MIR for `num_to_digit` after PreCodegen
 
 fn num_to_digit(_1: char) -> u32 {
-    debug num => _1;                     // in scope 0 at $DIR/issue-59352.rs:+0:21: +0:24
-    let mut _0: u32;                     // return place in scope 0 at $DIR/issue-59352.rs:+0:35: +0:38
-    let mut _2: char;                    // in scope 0 at $DIR/issue-59352.rs:+2:8: +2:11
-    let mut _3: std::option::Option<u32>; // in scope 0 at $DIR/issue-59352.rs:+2:26: +2:41
-    let mut _4: char;                    // in scope 0 at $DIR/issue-59352.rs:+2:26: +2:29
-    let mut _5: u32;                     // in scope 0 at $DIR/issue-59352.rs:+2:8: +2:23
+    debug num => _1;                     // in scope 0 at $DIR/issue_59352.rs:+0:21: +0:24
+    let mut _0: u32;                     // return place in scope 0 at $DIR/issue_59352.rs:+0:35: +0:38
+    let mut _2: char;                    // in scope 0 at $DIR/issue_59352.rs:+2:8: +2:11
+    let mut _3: std::option::Option<u32>; // in scope 0 at $DIR/issue_59352.rs:+2:26: +2:41
+    let mut _4: char;                    // in scope 0 at $DIR/issue_59352.rs:+2:26: +2:29
+    let mut _5: u32;                     // in scope 0 at $DIR/issue_59352.rs:+2:8: +2:23
     let mut _12: isize;                  // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-    scope 1 (inlined char::methods::<impl char>::is_digit) { // at $DIR/issue-59352.rs:14:8: 14:23
+    scope 1 (inlined char::methods::<impl char>::is_digit) { // at $DIR/issue_59352.rs:14:8: 14:23
         debug self => _2;                // in scope 1 at $SRC_DIR/core/src/char/methods.rs:LL:COL
         debug radix => _5;               // in scope 1 at $SRC_DIR/core/src/char/methods.rs:LL:COL
         let mut _6: &std::option::Option<u32>; // in scope 1 at $SRC_DIR/core/src/char/methods.rs:LL:COL
@@ -19,7 +19,7 @@ fn num_to_digit(_1: char) -> u32 {
             let mut _9: isize;           // in scope 2 at $SRC_DIR/core/src/option.rs:LL:COL
         }
     }
-    scope 3 (inlined #[track_caller] Option::<u32>::unwrap) { // at $DIR/issue-59352.rs:14:26: 14:50
+    scope 3 (inlined #[track_caller] Option::<u32>::unwrap) { // at $DIR/issue_59352.rs:14:26: 14:50
         debug self => _3;                // in scope 3 at $SRC_DIR/core/src/option.rs:LL:COL
         let mut _10: isize;              // in scope 3 at $SRC_DIR/core/src/option.rs:LL:COL
         let mut _11: !;                  // in scope 3 at $SRC_DIR/core/src/option.rs:LL:COL
@@ -29,9 +29,9 @@ fn num_to_digit(_1: char) -> u32 {
     }
 
     bb0: {
-        StorageLive(_2);                 // scope 0 at $DIR/issue-59352.rs:+2:8: +2:11
-        _2 = _1;                         // scope 0 at $DIR/issue-59352.rs:+2:8: +2:11
-        StorageLive(_5);                 // scope 0 at $DIR/issue-59352.rs:+2:8: +2:23
+        StorageLive(_2);                 // scope 0 at $DIR/issue_59352.rs:+2:8: +2:11
+        _2 = _1;                         // scope 0 at $DIR/issue_59352.rs:+2:8: +2:11
+        StorageLive(_5);                 // scope 0 at $DIR/issue_59352.rs:+2:8: +2:23
         StorageLive(_6);                 // scope 1 at $SRC_DIR/core/src/char/methods.rs:LL:COL
         StorageLive(_7);                 // scope 1 at $SRC_DIR/core/src/char/methods.rs:LL:COL
         StorageLive(_8);                 // scope 1 at $SRC_DIR/core/src/char/methods.rs:LL:COL
@@ -43,30 +43,30 @@ fn num_to_digit(_1: char) -> u32 {
     }
 
     bb1: {
-        StorageDead(_12);                // scope 0 at $DIR/issue-59352.rs:+2:8: +2:23
-        StorageLive(_3);                 // scope 0 at $DIR/issue-59352.rs:+2:26: +2:41
-        StorageLive(_4);                 // scope 0 at $DIR/issue-59352.rs:+2:26: +2:29
-        _4 = _1;                         // scope 0 at $DIR/issue-59352.rs:+2:26: +2:29
-        _3 = char::methods::<impl char>::to_digit(move _4, const 8_u32) -> bb2; // scope 0 at $DIR/issue-59352.rs:+2:26: +2:41
+        StorageDead(_12);                // scope 0 at $DIR/issue_59352.rs:+2:8: +2:23
+        StorageLive(_3);                 // scope 0 at $DIR/issue_59352.rs:+2:26: +2:41
+        StorageLive(_4);                 // scope 0 at $DIR/issue_59352.rs:+2:26: +2:29
+        _4 = _1;                         // scope 0 at $DIR/issue_59352.rs:+2:26: +2:29
+        _3 = char::methods::<impl char>::to_digit(move _4, const 8_u32) -> bb2; // scope 0 at $DIR/issue_59352.rs:+2:26: +2:41
                                          // mir::Constant
-                                         // + span: $DIR/issue-59352.rs:14:30: 14:38
+                                         // + span: $DIR/issue_59352.rs:14:30: 14:38
                                          // + literal: Const { ty: fn(char, u32) -> Option<u32> {char::methods::<impl char>::to_digit}, val: Value(<ZST>) }
     }
 
     bb2: {
-        StorageDead(_4);                 // scope 0 at $DIR/issue-59352.rs:+2:40: +2:41
+        StorageDead(_4);                 // scope 0 at $DIR/issue_59352.rs:+2:40: +2:41
         _10 = discriminant(_3);          // scope 3 at $SRC_DIR/core/src/option.rs:LL:COL
         switchInt(move _10) -> [0_isize: bb6, 1_isize: bb8, otherwise: bb7]; // scope 3 at $SRC_DIR/core/src/option.rs:LL:COL
     }
 
     bb3: {
-        StorageDead(_12);                // scope 0 at $DIR/issue-59352.rs:+2:8: +2:23
-        _0 = const 0_u32;                // scope 0 at $DIR/issue-59352.rs:+2:60: +2:61
-        goto -> bb4;                     // scope 0 at $DIR/issue-59352.rs:+2:5: +2:63
+        StorageDead(_12);                // scope 0 at $DIR/issue_59352.rs:+2:8: +2:23
+        _0 = const 0_u32;                // scope 0 at $DIR/issue_59352.rs:+2:60: +2:61
+        goto -> bb4;                     // scope 0 at $DIR/issue_59352.rs:+2:5: +2:63
     }
 
     bb4: {
-        return;                          // scope 0 at $DIR/issue-59352.rs:+3:2: +3:2
+        return;                          // scope 0 at $DIR/issue_59352.rs:+3:2: +3:2
     }
 
     bb5: {
@@ -77,9 +77,9 @@ fn num_to_digit(_1: char) -> u32 {
         _12 = move _9;                   // scope 2 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageDead(_6);                 // scope 1 at $SRC_DIR/core/src/char/methods.rs:LL:COL
         StorageDead(_7);                 // scope 1 at $SRC_DIR/core/src/char/methods.rs:LL:COL
-        StorageDead(_5);                 // scope 0 at $DIR/issue-59352.rs:+2:8: +2:23
-        StorageDead(_2);                 // scope 0 at $DIR/issue-59352.rs:+2:22: +2:23
-        switchInt(move _12) -> [1_isize: bb1, otherwise: bb3]; // scope 0 at $DIR/issue-59352.rs:+2:8: +2:23
+        StorageDead(_5);                 // scope 0 at $DIR/issue_59352.rs:+2:8: +2:23
+        StorageDead(_2);                 // scope 0 at $DIR/issue_59352.rs:+2:22: +2:23
+        switchInt(move _12) -> [1_isize: bb1, otherwise: bb3]; // scope 0 at $DIR/issue_59352.rs:+2:8: +2:23
     }
 
     bb6: {
@@ -99,7 +99,7 @@ fn num_to_digit(_1: char) -> u32 {
 
     bb8: {
         _0 = move ((_3 as Some).0: u32); // scope 3 at $SRC_DIR/core/src/option.rs:LL:COL
-        StorageDead(_3);                 // scope 0 at $DIR/issue-59352.rs:+2:49: +2:50
-        goto -> bb4;                     // scope 0 at $DIR/issue-59352.rs:+2:5: +2:63
+        StorageDead(_3);                 // scope 0 at $DIR/issue_59352.rs:+2:49: +2:50
+        goto -> bb4;                     // scope 0 at $DIR/issue_59352.rs:+2:5: +2:63
     }
 }
diff --git a/src/test/mir-opt/issues/issue-59352.rs b/src/test/mir-opt/issues/issue_59352.rs
similarity index 100%
rename from src/test/mir-opt/issues/issue-59352.rs
rename to src/test/mir-opt/issues/issue_59352.rs
diff --git a/src/test/mir-opt/issues/issue_75439.foo.MatchBranchSimplification.diff b/src/test/mir-opt/issues/issue_75439.foo.MatchBranchSimplification.diff
index 2ee4332ad382..87066cc62c02 100644
--- a/src/test/mir-opt/issues/issue_75439.foo.MatchBranchSimplification.diff
+++ b/src/test/mir-opt/issues/issue_75439.foo.MatchBranchSimplification.diff
@@ -2,17 +2,17 @@
 + // MIR for `foo` after MatchBranchSimplification
   
   fn foo(_1: [u8; 16]) -> Option<[u8; 4]> {
-      debug bytes => _1;                   // in scope 0 at $DIR/issue-75439.rs:+0:12: +0:17
-      let mut _0: std::option::Option<[u8; 4]>; // return place in scope 0 at $DIR/issue-75439.rs:+0:32: +0:47
-      let _2: [u32; 4];                    // in scope 0 at $DIR/issue-75439.rs:+2:9: +2:15
-      let mut _3: [u8; 16];                // in scope 0 at $DIR/issue-75439.rs:+2:47: +2:52
-      let mut _5: [u8; 4];                 // in scope 0 at $DIR/issue-75439.rs:+5:14: +5:38
-      let mut _6: u32;                     // in scope 0 at $DIR/issue-75439.rs:+5:33: +5:35
+      debug bytes => _1;                   // in scope 0 at $DIR/issue_75439.rs:+0:12: +0:17
+      let mut _0: std::option::Option<[u8; 4]>; // return place in scope 0 at $DIR/issue_75439.rs:+0:32: +0:47
+      let _2: [u32; 4];                    // in scope 0 at $DIR/issue_75439.rs:+2:9: +2:15
+      let mut _3: [u8; 16];                // in scope 0 at $DIR/issue_75439.rs:+2:47: +2:52
+      let mut _5: [u8; 4];                 // in scope 0 at $DIR/issue_75439.rs:+5:14: +5:38
+      let mut _6: u32;                     // in scope 0 at $DIR/issue_75439.rs:+5:33: +5:35
       scope 1 {
-          debug dwords => _2;              // in scope 1 at $DIR/issue-75439.rs:+2:9: +2:15
+          debug dwords => _2;              // in scope 1 at $DIR/issue_75439.rs:+2:9: +2:15
           scope 3 {
-              debug ip => _4;              // in scope 3 at $DIR/issue-75439.rs:+4:27: +4:29
-              let _4: u32;                 // in scope 3 at $DIR/issue-75439.rs:+4:27: +4:29
+              debug ip => _4;              // in scope 3 at $DIR/issue_75439.rs:+4:27: +4:29
+              let _4: u32;                 // in scope 3 at $DIR/issue_75439.rs:+4:27: +4:29
               scope 4 {
               }
           }
@@ -21,69 +21,69 @@
       }
   
       bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/issue-75439.rs:+2:9: +2:15
-          StorageLive(_3);                 // scope 2 at $DIR/issue-75439.rs:+2:47: +2:52
-          _3 = _1;                         // scope 2 at $DIR/issue-75439.rs:+2:47: +2:52
-          _2 = transmute::<[u8; 16], [u32; 4]>(move _3) -> bb1; // scope 2 at $DIR/issue-75439.rs:+2:37: +2:53
+          StorageLive(_2);                 // scope 0 at $DIR/issue_75439.rs:+2:9: +2:15
+          StorageLive(_3);                 // scope 2 at $DIR/issue_75439.rs:+2:47: +2:52
+          _3 = _1;                         // scope 2 at $DIR/issue_75439.rs:+2:47: +2:52
+          _2 = transmute::<[u8; 16], [u32; 4]>(move _3) -> bb1; // scope 2 at $DIR/issue_75439.rs:+2:37: +2:53
                                            // mir::Constant
-                                           // + span: $DIR/issue-75439.rs:7:37: 7:46
+                                           // + span: $DIR/issue_75439.rs:7:37: 7:46
                                            // + literal: Const { ty: unsafe extern "rust-intrinsic" fn([u8; 16]) -> [u32; 4] {transmute::<[u8; 16], [u32; 4]>}, val: Value(<ZST>) }
       }
   
       bb1: {
-          StorageDead(_3);                 // scope 2 at $DIR/issue-75439.rs:+2:52: +2:53
-          switchInt(_2[0 of 4]) -> [0_u32: bb2, otherwise: bb8]; // scope 3 at $DIR/issue-75439.rs:+4:12: +4:30
+          StorageDead(_3);                 // scope 2 at $DIR/issue_75439.rs:+2:52: +2:53
+          switchInt(_2[0 of 4]) -> [0_u32: bb2, otherwise: bb8]; // scope 3 at $DIR/issue_75439.rs:+4:12: +4:30
       }
   
       bb2: {
-          switchInt(_2[1 of 4]) -> [0_u32: bb3, otherwise: bb8]; // scope 3 at $DIR/issue-75439.rs:+4:12: +4:30
+          switchInt(_2[1 of 4]) -> [0_u32: bb3, otherwise: bb8]; // scope 3 at $DIR/issue_75439.rs:+4:12: +4:30
       }
   
       bb3: {
-          switchInt(_2[2 of 4]) -> [0_u32: bb5, 4294901760_u32: bb6, otherwise: bb8]; // scope 3 at $DIR/issue-75439.rs:+4:12: +4:30
+          switchInt(_2[2 of 4]) -> [0_u32: bb5, 4294901760_u32: bb6, otherwise: bb8]; // scope 3 at $DIR/issue_75439.rs:+4:12: +4:30
       }
   
       bb4: {
-          StorageLive(_5);                 // scope 3 at $DIR/issue-75439.rs:+5:14: +5:38
-          StorageLive(_6);                 // scope 4 at $DIR/issue-75439.rs:+5:33: +5:35
-          _6 = _4;                         // scope 4 at $DIR/issue-75439.rs:+5:33: +5:35
-          _5 = transmute::<u32, [u8; 4]>(move _6) -> bb7; // scope 4 at $DIR/issue-75439.rs:+5:23: +5:36
+          StorageLive(_5);                 // scope 3 at $DIR/issue_75439.rs:+5:14: +5:38
+          StorageLive(_6);                 // scope 4 at $DIR/issue_75439.rs:+5:33: +5:35
+          _6 = _4;                         // scope 4 at $DIR/issue_75439.rs:+5:33: +5:35
+          _5 = transmute::<u32, [u8; 4]>(move _6) -> bb7; // scope 4 at $DIR/issue_75439.rs:+5:23: +5:36
                                            // mir::Constant
-                                           // + span: $DIR/issue-75439.rs:10:23: 10:32
+                                           // + span: $DIR/issue_75439.rs:10:23: 10:32
                                            // + literal: Const { ty: unsafe extern "rust-intrinsic" fn(u32) -> [u8; 4] {transmute::<u32, [u8; 4]>}, val: Value(<ZST>) }
       }
   
       bb5: {
-          StorageLive(_4);                 // scope 3 at $DIR/issue-75439.rs:+4:27: +4:29
-          _4 = _2[3 of 4];                 // scope 3 at $DIR/issue-75439.rs:+4:27: +4:29
-          goto -> bb4;                     // scope 3 at $DIR/issue-75439.rs:+4:12: +4:30
+          StorageLive(_4);                 // scope 3 at $DIR/issue_75439.rs:+4:27: +4:29
+          _4 = _2[3 of 4];                 // scope 3 at $DIR/issue_75439.rs:+4:27: +4:29
+          goto -> bb4;                     // scope 3 at $DIR/issue_75439.rs:+4:12: +4:30
       }
   
       bb6: {
-          StorageLive(_4);                 // scope 3 at $DIR/issue-75439.rs:+4:27: +4:29
-          _4 = _2[3 of 4];                 // scope 3 at $DIR/issue-75439.rs:+4:27: +4:29
-          goto -> bb4;                     // scope 3 at $DIR/issue-75439.rs:+4:12: +4:30
+          StorageLive(_4);                 // scope 3 at $DIR/issue_75439.rs:+4:27: +4:29
+          _4 = _2[3 of 4];                 // scope 3 at $DIR/issue_75439.rs:+4:27: +4:29
+          goto -> bb4;                     // scope 3 at $DIR/issue_75439.rs:+4:12: +4:30
       }
   
       bb7: {
-          StorageDead(_6);                 // scope 4 at $DIR/issue-75439.rs:+5:35: +5:36
-          Deinit(_0);                      // scope 3 at $DIR/issue-75439.rs:+5:9: +5:39
-          ((_0 as Some).0: [u8; 4]) = move _5; // scope 3 at $DIR/issue-75439.rs:+5:9: +5:39
-          discriminant(_0) = 1;            // scope 3 at $DIR/issue-75439.rs:+5:9: +5:39
-          StorageDead(_5);                 // scope 3 at $DIR/issue-75439.rs:+5:38: +5:39
-          StorageDead(_4);                 // scope 1 at $DIR/issue-75439.rs:+6:5: +6:6
-          goto -> bb9;                     // scope 1 at $DIR/issue-75439.rs:+4:5: +8:6
+          StorageDead(_6);                 // scope 4 at $DIR/issue_75439.rs:+5:35: +5:36
+          Deinit(_0);                      // scope 3 at $DIR/issue_75439.rs:+5:9: +5:39
+          ((_0 as Some).0: [u8; 4]) = move _5; // scope 3 at $DIR/issue_75439.rs:+5:9: +5:39
+          discriminant(_0) = 1;            // scope 3 at $DIR/issue_75439.rs:+5:9: +5:39
+          StorageDead(_5);                 // scope 3 at $DIR/issue_75439.rs:+5:38: +5:39
+          StorageDead(_4);                 // scope 1 at $DIR/issue_75439.rs:+6:5: +6:6
+          goto -> bb9;                     // scope 1 at $DIR/issue_75439.rs:+4:5: +8:6
       }
   
       bb8: {
-          Deinit(_0);                      // scope 1 at $DIR/issue-75439.rs:+7:9: +7:13
-          discriminant(_0) = 0;            // scope 1 at $DIR/issue-75439.rs:+7:9: +7:13
-          goto -> bb9;                     // scope 1 at $DIR/issue-75439.rs:+4:5: +8:6
+          Deinit(_0);                      // scope 1 at $DIR/issue_75439.rs:+7:9: +7:13
+          discriminant(_0) = 0;            // scope 1 at $DIR/issue_75439.rs:+7:9: +7:13
+          goto -> bb9;                     // scope 1 at $DIR/issue_75439.rs:+4:5: +8:6
       }
   
       bb9: {
-          StorageDead(_2);                 // scope 0 at $DIR/issue-75439.rs:+9:1: +9:2
-          return;                          // scope 0 at $DIR/issue-75439.rs:+9:2: +9:2
+          StorageDead(_2);                 // scope 0 at $DIR/issue_75439.rs:+9:1: +9:2
+          return;                          // scope 0 at $DIR/issue_75439.rs:+9:2: +9:2
       }
   }
   
diff --git a/src/test/mir-opt/issues/issue-75439.rs b/src/test/mir-opt/issues/issue_75439.rs
similarity index 100%
rename from src/test/mir-opt/issues/issue-75439.rs
rename to src/test/mir-opt/issues/issue_75439.rs
diff --git a/src/test/mir-opt/lower_intrinsics_e2e.f_u64.PreCodegen.after.mir b/src/test/mir-opt/lower_intrinsics_e2e.f_u64.PreCodegen.after.mir
index 8e185323e1a8..f6d8bdd74228 100644
--- a/src/test/mir-opt/lower_intrinsics_e2e.f_u64.PreCodegen.after.mir
+++ b/src/test/mir-opt/lower_intrinsics_e2e.f_u64.PreCodegen.after.mir
@@ -6,25 +6,20 @@ fn f_u64() -> () {
     scope 1 (inlined f_dispatch::<u64>) { // at $DIR/lower_intrinsics_e2e.rs:15:5: 15:21
         debug t => _1;                   // in scope 1 at $DIR/lower_intrinsics_e2e.rs:19:22: 19:23
         let _2: ();                      // in scope 1 at $DIR/lower_intrinsics_e2e.rs:23:9: 23:21
-        let mut _3: u64;                 // in scope 1 at $DIR/lower_intrinsics_e2e.rs:23:19: 23:20
         scope 2 (inlined std::mem::size_of::<u64>) { // at $DIR/lower_intrinsics_e2e.rs:20:8: 20:32
         }
     }
 
     bb0: {
         StorageLive(_1);                 // scope 0 at $DIR/lower_intrinsics_e2e.rs:+1:5: +1:21
-        _1 = const 0_u64;                // scope 0 at $DIR/lower_intrinsics_e2e.rs:+1:5: +1:21
         StorageLive(_2);                 // scope 1 at $DIR/lower_intrinsics_e2e.rs:23:9: 23:21
-        StorageLive(_3);                 // scope 1 at $DIR/lower_intrinsics_e2e.rs:23:19: 23:20
-        _3 = move _1;                    // scope 1 at $DIR/lower_intrinsics_e2e.rs:23:19: 23:20
-        _2 = f_non_zst::<u64>(move _3) -> bb1; // scope 1 at $DIR/lower_intrinsics_e2e.rs:23:9: 23:21
+        _2 = f_non_zst::<u64>(const 0_u64) -> bb1; // scope 1 at $DIR/lower_intrinsics_e2e.rs:23:9: 23:21
                                          // mir::Constant
                                          // + span: $DIR/lower_intrinsics_e2e.rs:23:9: 23:18
                                          // + literal: Const { ty: fn(u64) {f_non_zst::<u64>}, val: Value(<ZST>) }
     }
 
     bb1: {
-        StorageDead(_3);                 // scope 1 at $DIR/lower_intrinsics_e2e.rs:23:20: 23:21
         StorageDead(_2);                 // scope 1 at $DIR/lower_intrinsics_e2e.rs:23:21: 23:22
         StorageDead(_1);                 // scope 0 at $DIR/lower_intrinsics_e2e.rs:+1:5: +1:21
         return;                          // scope 0 at $DIR/lower_intrinsics_e2e.rs:+2:2: +2:2
diff --git a/src/test/mir-opt/match_arm_scopes.complicated_match.SimplifyCfg-initial.after-ElaborateDrops.after.diff b/src/test/mir-opt/match_arm_scopes.complicated_match.SimplifyCfg-initial.after-ElaborateDrops.after.diff
index 25ab0c9f7f4c..d3db3b182717 100644
--- a/src/test/mir-opt/match_arm_scopes.complicated_match.SimplifyCfg-initial.after-ElaborateDrops.after.diff
+++ b/src/test/mir-opt/match_arm_scopes.complicated_match.SimplifyCfg-initial.after-ElaborateDrops.after.diff
@@ -2,271 +2,271 @@
 + // MIR for `complicated_match` after ElaborateDrops
   
   fn complicated_match(_1: bool, _2: (bool, bool, String)) -> i32 {
-      debug cond => _1;                    // in scope 0 at $DIR/match-arm-scopes.rs:+0:22: +0:26
-      debug items => _2;                   // in scope 0 at $DIR/match-arm-scopes.rs:+0:34: +0:39
-      let mut _0: i32;                     // return place in scope 0 at $DIR/match-arm-scopes.rs:+0:66: +0:69
-      let mut _3: &bool;                   // in scope 0 at $DIR/match-arm-scopes.rs:+1:11: +1:16
-      let mut _4: &bool;                   // in scope 0 at $DIR/match-arm-scopes.rs:+1:11: +1:16
-      let _5: bool;                        // in scope 0 at $DIR/match-arm-scopes.rs:+2:17: +2:18
-      let _6: &bool;                       // in scope 0 at $DIR/match-arm-scopes.rs:+2:17: +2:18
-      let _7: std::string::String;         // in scope 0 at $DIR/match-arm-scopes.rs:+2:20: +2:21
-      let _8: &std::string::String;        // in scope 0 at $DIR/match-arm-scopes.rs:+2:20: +2:21
-      let mut _9: bool;                    // in scope 0 at $DIR/match-arm-scopes.rs:+2:42: +2:73
-      let mut _10: bool;                   // in scope 0 at $DIR/match-arm-scopes.rs:+2:45: +2:49
-      let mut _11: !;                      // in scope 0 at $DIR/match-arm-scopes.rs:+2:52: +2:60
-      let mut _12: bool;                   // in scope 0 at $DIR/match-arm-scopes.rs:+2:42: +2:73
-      let mut _13: bool;                   // in scope 0 at $DIR/match-arm-scopes.rs:+2:45: +2:49
-      let mut _14: !;                      // in scope 0 at $DIR/match-arm-scopes.rs:+2:52: +2:60
-      let _15: bool;                       // in scope 0 at $DIR/match-arm-scopes.rs:+3:16: +3:17
-      let _16: std::string::String;        // in scope 0 at $DIR/match-arm-scopes.rs:+3:19: +3:20
+      debug cond => _1;                    // in scope 0 at $DIR/match_arm_scopes.rs:+0:22: +0:26
+      debug items => _2;                   // in scope 0 at $DIR/match_arm_scopes.rs:+0:34: +0:39
+      let mut _0: i32;                     // return place in scope 0 at $DIR/match_arm_scopes.rs:+0:66: +0:69
+      let mut _3: &bool;                   // in scope 0 at $DIR/match_arm_scopes.rs:+1:11: +1:16
+      let mut _4: &bool;                   // in scope 0 at $DIR/match_arm_scopes.rs:+1:11: +1:16
+      let _5: bool;                        // in scope 0 at $DIR/match_arm_scopes.rs:+2:17: +2:18
+      let _6: &bool;                       // in scope 0 at $DIR/match_arm_scopes.rs:+2:17: +2:18
+      let _7: std::string::String;         // in scope 0 at $DIR/match_arm_scopes.rs:+2:20: +2:21
+      let _8: &std::string::String;        // in scope 0 at $DIR/match_arm_scopes.rs:+2:20: +2:21
+      let mut _9: bool;                    // in scope 0 at $DIR/match_arm_scopes.rs:+2:42: +2:73
+      let mut _10: bool;                   // in scope 0 at $DIR/match_arm_scopes.rs:+2:45: +2:49
+      let mut _11: !;                      // in scope 0 at $DIR/match_arm_scopes.rs:+2:52: +2:60
+      let mut _12: bool;                   // in scope 0 at $DIR/match_arm_scopes.rs:+2:42: +2:73
+      let mut _13: bool;                   // in scope 0 at $DIR/match_arm_scopes.rs:+2:45: +2:49
+      let mut _14: !;                      // in scope 0 at $DIR/match_arm_scopes.rs:+2:52: +2:60
+      let _15: bool;                       // in scope 0 at $DIR/match_arm_scopes.rs:+3:16: +3:17
+      let _16: std::string::String;        // in scope 0 at $DIR/match_arm_scopes.rs:+3:19: +3:20
       scope 1 {
-          debug a => _5;                   // in scope 1 at $DIR/match-arm-scopes.rs:+2:17: +2:18
-          debug a => _6;                   // in scope 1 at $DIR/match-arm-scopes.rs:+2:17: +2:18
-          debug s => _7;                   // in scope 1 at $DIR/match-arm-scopes.rs:+2:20: +2:21
-          debug s => _8;                   // in scope 1 at $DIR/match-arm-scopes.rs:+2:20: +2:21
+          debug a => _5;                   // in scope 1 at $DIR/match_arm_scopes.rs:+2:17: +2:18
+          debug a => _6;                   // in scope 1 at $DIR/match_arm_scopes.rs:+2:17: +2:18
+          debug s => _7;                   // in scope 1 at $DIR/match_arm_scopes.rs:+2:20: +2:21
+          debug s => _8;                   // in scope 1 at $DIR/match_arm_scopes.rs:+2:20: +2:21
       }
       scope 2 {
-          debug b => _15;                  // in scope 2 at $DIR/match-arm-scopes.rs:+3:16: +3:17
-          debug t => _16;                  // in scope 2 at $DIR/match-arm-scopes.rs:+3:19: +3:20
+          debug b => _15;                  // in scope 2 at $DIR/match_arm_scopes.rs:+3:16: +3:17
+          debug t => _16;                  // in scope 2 at $DIR/match_arm_scopes.rs:+3:19: +3:20
       }
   
       bb0: {
--         FakeRead(ForMatchedPlace(None), _2); // scope 0 at $DIR/match-arm-scopes.rs:+1:11: +1:16
--         switchInt((_2.0: bool)) -> [false: bb1, otherwise: bb2]; // scope 0 at $DIR/match-arm-scopes.rs:+1:5: +1:16
-+         switchInt((_2.0: bool)) -> [false: bb5, otherwise: bb1]; // scope 0 at $DIR/match-arm-scopes.rs:+1:5: +1:16
+-         FakeRead(ForMatchedPlace(None), _2); // scope 0 at $DIR/match_arm_scopes.rs:+1:11: +1:16
+-         switchInt((_2.0: bool)) -> [false: bb1, otherwise: bb2]; // scope 0 at $DIR/match_arm_scopes.rs:+1:5: +1:16
++         switchInt((_2.0: bool)) -> [false: bb5, otherwise: bb1]; // scope 0 at $DIR/match_arm_scopes.rs:+1:5: +1:16
       }
   
       bb1: {
--         falseEdge -> [real: bb8, imaginary: bb3]; // scope 0 at $DIR/match-arm-scopes.rs:+2:9: +2:22
-+         switchInt((_2.1: bool)) -> [false: bb10, otherwise: bb2]; // scope 0 at $DIR/match-arm-scopes.rs:+1:5: +1:16
+-         falseEdge -> [real: bb8, imaginary: bb3]; // scope 0 at $DIR/match_arm_scopes.rs:+2:9: +2:22
++         switchInt((_2.1: bool)) -> [false: bb10, otherwise: bb2]; // scope 0 at $DIR/match_arm_scopes.rs:+1:5: +1:16
       }
   
       bb2: {
--         switchInt((_2.1: bool)) -> [false: bb3, otherwise: bb4]; // scope 0 at $DIR/match-arm-scopes.rs:+1:5: +1:16
-+         switchInt((_2.0: bool)) -> [false: bb3, otherwise: bb17]; // scope 0 at $DIR/match-arm-scopes.rs:+1:5: +1:16
+-         switchInt((_2.1: bool)) -> [false: bb3, otherwise: bb4]; // scope 0 at $DIR/match_arm_scopes.rs:+1:5: +1:16
++         switchInt((_2.0: bool)) -> [false: bb3, otherwise: bb17]; // scope 0 at $DIR/match_arm_scopes.rs:+1:5: +1:16
       }
   
       bb3: {
--         falseEdge -> [real: bb13, imaginary: bb5]; // scope 0 at $DIR/match-arm-scopes.rs:+2:25: +2:38
+-         falseEdge -> [real: bb13, imaginary: bb5]; // scope 0 at $DIR/match_arm_scopes.rs:+2:25: +2:38
 -     }
 - 
 -     bb4: {
--         switchInt((_2.0: bool)) -> [false: bb6, otherwise: bb5]; // scope 0 at $DIR/match-arm-scopes.rs:+1:5: +1:16
+-         switchInt((_2.0: bool)) -> [false: bb6, otherwise: bb5]; // scope 0 at $DIR/match_arm_scopes.rs:+1:5: +1:16
 -     }
 - 
 -     bb5: {
--         falseEdge -> [real: bb20, imaginary: bb6]; // scope 0 at $DIR/match-arm-scopes.rs:+3:9: +3:21
+-         falseEdge -> [real: bb20, imaginary: bb6]; // scope 0 at $DIR/match_arm_scopes.rs:+3:9: +3:21
 -     }
 - 
 -     bb6: {
-          StorageLive(_15);                // scope 0 at $DIR/match-arm-scopes.rs:+3:32: +3:33
-          _15 = (_2.1: bool);              // scope 0 at $DIR/match-arm-scopes.rs:+3:32: +3:33
-          StorageLive(_16);                // scope 0 at $DIR/match-arm-scopes.rs:+3:35: +3:36
-          _16 = move (_2.2: std::string::String); // scope 0 at $DIR/match-arm-scopes.rs:+3:35: +3:36
--         goto -> bb19;                    // scope 0 at $DIR/match-arm-scopes.rs:+1:5: +4:6
-+         goto -> bb16;                    // scope 0 at $DIR/match-arm-scopes.rs:+1:5: +4:6
+          StorageLive(_15);                // scope 0 at $DIR/match_arm_scopes.rs:+3:32: +3:33
+          _15 = (_2.1: bool);              // scope 0 at $DIR/match_arm_scopes.rs:+3:32: +3:33
+          StorageLive(_16);                // scope 0 at $DIR/match_arm_scopes.rs:+3:35: +3:36
+          _16 = move (_2.2: std::string::String); // scope 0 at $DIR/match_arm_scopes.rs:+3:35: +3:36
+-         goto -> bb19;                    // scope 0 at $DIR/match_arm_scopes.rs:+1:5: +4:6
++         goto -> bb16;                    // scope 0 at $DIR/match_arm_scopes.rs:+1:5: +4:6
       }
   
 -     bb7: {
 +     bb4: {
-          _0 = const 1_i32;                // scope 1 at $DIR/match-arm-scopes.rs:+2:77: +2:78
--         drop(_7) -> [return: bb18, unwind: bb25]; // scope 0 at $DIR/match-arm-scopes.rs:+2:77: +2:78
-+         drop(_7) -> [return: bb15, unwind: bb22]; // scope 0 at $DIR/match-arm-scopes.rs:+2:77: +2:78
+          _0 = const 1_i32;                // scope 1 at $DIR/match_arm_scopes.rs:+2:77: +2:78
+-         drop(_7) -> [return: bb18, unwind: bb25]; // scope 0 at $DIR/match_arm_scopes.rs:+2:77: +2:78
++         drop(_7) -> [return: bb15, unwind: bb22]; // scope 0 at $DIR/match_arm_scopes.rs:+2:77: +2:78
       }
   
 -     bb8: {
 +     bb5: {
-          StorageLive(_6);                 // scope 0 at $DIR/match-arm-scopes.rs:+2:17: +2:18
-          _6 = &(_2.1: bool);              // scope 0 at $DIR/match-arm-scopes.rs:+2:17: +2:18
-          StorageLive(_8);                 // scope 0 at $DIR/match-arm-scopes.rs:+2:20: +2:21
-          _8 = &(_2.2: std::string::String); // scope 0 at $DIR/match-arm-scopes.rs:+2:20: +2:21
--         _3 = &shallow (_2.0: bool);      // scope 0 at $DIR/match-arm-scopes.rs:+1:11: +1:16
--         _4 = &shallow (_2.1: bool);      // scope 0 at $DIR/match-arm-scopes.rs:+1:11: +1:16
-          StorageLive(_9);                 // scope 0 at $DIR/match-arm-scopes.rs:+2:42: +2:73
-          StorageLive(_10);                // scope 0 at $DIR/match-arm-scopes.rs:+2:45: +2:49
-          _10 = _1;                        // scope 0 at $DIR/match-arm-scopes.rs:+2:45: +2:49
--         switchInt(move _10) -> [false: bb10, otherwise: bb9]; // scope 0 at $DIR/match-arm-scopes.rs:+2:45: +2:49
-+         switchInt(move _10) -> [false: bb7, otherwise: bb6]; // scope 0 at $DIR/match-arm-scopes.rs:+2:45: +2:49
+          StorageLive(_6);                 // scope 0 at $DIR/match_arm_scopes.rs:+2:17: +2:18
+          _6 = &(_2.1: bool);              // scope 0 at $DIR/match_arm_scopes.rs:+2:17: +2:18
+          StorageLive(_8);                 // scope 0 at $DIR/match_arm_scopes.rs:+2:20: +2:21
+          _8 = &(_2.2: std::string::String); // scope 0 at $DIR/match_arm_scopes.rs:+2:20: +2:21
+-         _3 = &shallow (_2.0: bool);      // scope 0 at $DIR/match_arm_scopes.rs:+1:11: +1:16
+-         _4 = &shallow (_2.1: bool);      // scope 0 at $DIR/match_arm_scopes.rs:+1:11: +1:16
+          StorageLive(_9);                 // scope 0 at $DIR/match_arm_scopes.rs:+2:42: +2:73
+          StorageLive(_10);                // scope 0 at $DIR/match_arm_scopes.rs:+2:45: +2:49
+          _10 = _1;                        // scope 0 at $DIR/match_arm_scopes.rs:+2:45: +2:49
+-         switchInt(move _10) -> [false: bb10, otherwise: bb9]; // scope 0 at $DIR/match_arm_scopes.rs:+2:45: +2:49
++         switchInt(move _10) -> [false: bb7, otherwise: bb6]; // scope 0 at $DIR/match_arm_scopes.rs:+2:45: +2:49
       }
   
 -     bb9: {
 +     bb6: {
-          _0 = const 3_i32;                // scope 0 at $DIR/match-arm-scopes.rs:+2:59: +2:60
-          StorageDead(_10);                // scope 0 at $DIR/match-arm-scopes.rs:+2:72: +2:73
-          StorageDead(_9);                 // scope 0 at $DIR/match-arm-scopes.rs:+2:72: +2:73
+          _0 = const 3_i32;                // scope 0 at $DIR/match_arm_scopes.rs:+2:59: +2:60
+          StorageDead(_10);                // scope 0 at $DIR/match_arm_scopes.rs:+2:72: +2:73
+          StorageDead(_9);                 // scope 0 at $DIR/match_arm_scopes.rs:+2:72: +2:73
 -         goto -> bb23;                    // scope 0 at no-location
 +         goto -> bb20;                    // scope 0 at no-location
       }
   
 -     bb10: {
 +     bb7: {
-          _9 = (*_6);                      // scope 0 at $DIR/match-arm-scopes.rs:+2:70: +2:71
--         switchInt(move _9) -> [false: bb12, otherwise: bb11]; // scope 0 at $DIR/match-arm-scopes.rs:+2:42: +2:73
-+         switchInt(move _9) -> [false: bb9, otherwise: bb8]; // scope 0 at $DIR/match-arm-scopes.rs:+2:42: +2:73
+          _9 = (*_6);                      // scope 0 at $DIR/match_arm_scopes.rs:+2:70: +2:71
+-         switchInt(move _9) -> [false: bb12, otherwise: bb11]; // scope 0 at $DIR/match_arm_scopes.rs:+2:42: +2:73
++         switchInt(move _9) -> [false: bb9, otherwise: bb8]; // scope 0 at $DIR/match_arm_scopes.rs:+2:42: +2:73
       }
   
 -     bb11: {
 +     bb8: {
-          StorageDead(_10);                // scope 0 at $DIR/match-arm-scopes.rs:+2:72: +2:73
-          StorageDead(_9);                 // scope 0 at $DIR/match-arm-scopes.rs:+2:72: +2:73
--         FakeRead(ForMatchGuard, _3);     // scope 0 at $DIR/match-arm-scopes.rs:+2:72: +2:73
--         FakeRead(ForMatchGuard, _4);     // scope 0 at $DIR/match-arm-scopes.rs:+2:72: +2:73
--         FakeRead(ForGuardBinding, _6);   // scope 0 at $DIR/match-arm-scopes.rs:+2:72: +2:73
--         FakeRead(ForGuardBinding, _8);   // scope 0 at $DIR/match-arm-scopes.rs:+2:72: +2:73
-          StorageLive(_5);                 // scope 0 at $DIR/match-arm-scopes.rs:+2:17: +2:18
-          _5 = (_2.1: bool);               // scope 0 at $DIR/match-arm-scopes.rs:+2:17: +2:18
-          StorageLive(_7);                 // scope 0 at $DIR/match-arm-scopes.rs:+2:20: +2:21
-          _7 = move (_2.2: std::string::String); // scope 0 at $DIR/match-arm-scopes.rs:+2:20: +2:21
--         goto -> bb7;                     // scope 0 at $DIR/match-arm-scopes.rs:+1:5: +4:6
-+         goto -> bb4;                     // scope 0 at $DIR/match-arm-scopes.rs:+1:5: +4:6
+          StorageDead(_10);                // scope 0 at $DIR/match_arm_scopes.rs:+2:72: +2:73
+          StorageDead(_9);                 // scope 0 at $DIR/match_arm_scopes.rs:+2:72: +2:73
+-         FakeRead(ForMatchGuard, _3);     // scope 0 at $DIR/match_arm_scopes.rs:+2:72: +2:73
+-         FakeRead(ForMatchGuard, _4);     // scope 0 at $DIR/match_arm_scopes.rs:+2:72: +2:73
+-         FakeRead(ForGuardBinding, _6);   // scope 0 at $DIR/match_arm_scopes.rs:+2:72: +2:73
+-         FakeRead(ForGuardBinding, _8);   // scope 0 at $DIR/match_arm_scopes.rs:+2:72: +2:73
+          StorageLive(_5);                 // scope 0 at $DIR/match_arm_scopes.rs:+2:17: +2:18
+          _5 = (_2.1: bool);               // scope 0 at $DIR/match_arm_scopes.rs:+2:17: +2:18
+          StorageLive(_7);                 // scope 0 at $DIR/match_arm_scopes.rs:+2:20: +2:21
+          _7 = move (_2.2: std::string::String); // scope 0 at $DIR/match_arm_scopes.rs:+2:20: +2:21
+-         goto -> bb7;                     // scope 0 at $DIR/match_arm_scopes.rs:+1:5: +4:6
++         goto -> bb4;                     // scope 0 at $DIR/match_arm_scopes.rs:+1:5: +4:6
       }
   
 -     bb12: {
 +     bb9: {
-          StorageDead(_10);                // scope 0 at $DIR/match-arm-scopes.rs:+2:72: +2:73
-          StorageDead(_9);                 // scope 0 at $DIR/match-arm-scopes.rs:+2:72: +2:73
-          StorageDead(_8);                 // scope 0 at $DIR/match-arm-scopes.rs:+2:77: +2:78
-          StorageDead(_6);                 // scope 0 at $DIR/match-arm-scopes.rs:+2:77: +2:78
--         falseEdge -> [real: bb2, imaginary: bb3]; // scope 0 at $DIR/match-arm-scopes.rs:+2:42: +2:73
-+         goto -> bb1;                     // scope 0 at $DIR/match-arm-scopes.rs:+2:42: +2:73
+          StorageDead(_10);                // scope 0 at $DIR/match_arm_scopes.rs:+2:72: +2:73
+          StorageDead(_9);                 // scope 0 at $DIR/match_arm_scopes.rs:+2:72: +2:73
+          StorageDead(_8);                 // scope 0 at $DIR/match_arm_scopes.rs:+2:77: +2:78
+          StorageDead(_6);                 // scope 0 at $DIR/match_arm_scopes.rs:+2:77: +2:78
+-         falseEdge -> [real: bb2, imaginary: bb3]; // scope 0 at $DIR/match_arm_scopes.rs:+2:42: +2:73
++         goto -> bb1;                     // scope 0 at $DIR/match_arm_scopes.rs:+2:42: +2:73
       }
   
 -     bb13: {
 +     bb10: {
-          StorageLive(_6);                 // scope 0 at $DIR/match-arm-scopes.rs:+2:26: +2:27
-          _6 = &(_2.0: bool);              // scope 0 at $DIR/match-arm-scopes.rs:+2:26: +2:27
-          StorageLive(_8);                 // scope 0 at $DIR/match-arm-scopes.rs:+2:36: +2:37
-          _8 = &(_2.2: std::string::String); // scope 0 at $DIR/match-arm-scopes.rs:+2:36: +2:37
--         _3 = &shallow (_2.0: bool);      // scope 0 at $DIR/match-arm-scopes.rs:+1:11: +1:16
--         _4 = &shallow (_2.1: bool);      // scope 0 at $DIR/match-arm-scopes.rs:+1:11: +1:16
-          StorageLive(_12);                // scope 0 at $DIR/match-arm-scopes.rs:+2:42: +2:73
-          StorageLive(_13);                // scope 0 at $DIR/match-arm-scopes.rs:+2:45: +2:49
-          _13 = _1;                        // scope 0 at $DIR/match-arm-scopes.rs:+2:45: +2:49
--         switchInt(move _13) -> [false: bb15, otherwise: bb14]; // scope 0 at $DIR/match-arm-scopes.rs:+2:45: +2:49
-+         switchInt(move _13) -> [false: bb12, otherwise: bb11]; // scope 0 at $DIR/match-arm-scopes.rs:+2:45: +2:49
+          StorageLive(_6);                 // scope 0 at $DIR/match_arm_scopes.rs:+2:26: +2:27
+          _6 = &(_2.0: bool);              // scope 0 at $DIR/match_arm_scopes.rs:+2:26: +2:27
+          StorageLive(_8);                 // scope 0 at $DIR/match_arm_scopes.rs:+2:36: +2:37
+          _8 = &(_2.2: std::string::String); // scope 0 at $DIR/match_arm_scopes.rs:+2:36: +2:37
+-         _3 = &shallow (_2.0: bool);      // scope 0 at $DIR/match_arm_scopes.rs:+1:11: +1:16
+-         _4 = &shallow (_2.1: bool);      // scope 0 at $DIR/match_arm_scopes.rs:+1:11: +1:16
+          StorageLive(_12);                // scope 0 at $DIR/match_arm_scopes.rs:+2:42: +2:73
+          StorageLive(_13);                // scope 0 at $DIR/match_arm_scopes.rs:+2:45: +2:49
+          _13 = _1;                        // scope 0 at $DIR/match_arm_scopes.rs:+2:45: +2:49
+-         switchInt(move _13) -> [false: bb15, otherwise: bb14]; // scope 0 at $DIR/match_arm_scopes.rs:+2:45: +2:49
++         switchInt(move _13) -> [false: bb12, otherwise: bb11]; // scope 0 at $DIR/match_arm_scopes.rs:+2:45: +2:49
       }
   
 -     bb14: {
 +     bb11: {
-          _0 = const 3_i32;                // scope 0 at $DIR/match-arm-scopes.rs:+2:59: +2:60
-          StorageDead(_13);                // scope 0 at $DIR/match-arm-scopes.rs:+2:72: +2:73
-          StorageDead(_12);                // scope 0 at $DIR/match-arm-scopes.rs:+2:72: +2:73
+          _0 = const 3_i32;                // scope 0 at $DIR/match_arm_scopes.rs:+2:59: +2:60
+          StorageDead(_13);                // scope 0 at $DIR/match_arm_scopes.rs:+2:72: +2:73
+          StorageDead(_12);                // scope 0 at $DIR/match_arm_scopes.rs:+2:72: +2:73
 -         goto -> bb23;                    // scope 0 at no-location
 +         goto -> bb20;                    // scope 0 at no-location
       }
   
 -     bb15: {
 +     bb12: {
-          _12 = (*_6);                     // scope 0 at $DIR/match-arm-scopes.rs:+2:70: +2:71
--         switchInt(move _12) -> [false: bb17, otherwise: bb16]; // scope 0 at $DIR/match-arm-scopes.rs:+2:42: +2:73
-+         switchInt(move _12) -> [false: bb14, otherwise: bb13]; // scope 0 at $DIR/match-arm-scopes.rs:+2:42: +2:73
+          _12 = (*_6);                     // scope 0 at $DIR/match_arm_scopes.rs:+2:70: +2:71
+-         switchInt(move _12) -> [false: bb17, otherwise: bb16]; // scope 0 at $DIR/match_arm_scopes.rs:+2:42: +2:73
++         switchInt(move _12) -> [false: bb14, otherwise: bb13]; // scope 0 at $DIR/match_arm_scopes.rs:+2:42: +2:73
       }
   
 -     bb16: {
 +     bb13: {
-          StorageDead(_13);                // scope 0 at $DIR/match-arm-scopes.rs:+2:72: +2:73
-          StorageDead(_12);                // scope 0 at $DIR/match-arm-scopes.rs:+2:72: +2:73
--         FakeRead(ForMatchGuard, _3);     // scope 0 at $DIR/match-arm-scopes.rs:+2:72: +2:73
--         FakeRead(ForMatchGuard, _4);     // scope 0 at $DIR/match-arm-scopes.rs:+2:72: +2:73
--         FakeRead(ForGuardBinding, _6);   // scope 0 at $DIR/match-arm-scopes.rs:+2:72: +2:73
--         FakeRead(ForGuardBinding, _8);   // scope 0 at $DIR/match-arm-scopes.rs:+2:72: +2:73
-          StorageLive(_5);                 // scope 0 at $DIR/match-arm-scopes.rs:+2:26: +2:27
-          _5 = (_2.0: bool);               // scope 0 at $DIR/match-arm-scopes.rs:+2:26: +2:27
-          StorageLive(_7);                 // scope 0 at $DIR/match-arm-scopes.rs:+2:36: +2:37
-          _7 = move (_2.2: std::string::String); // scope 0 at $DIR/match-arm-scopes.rs:+2:36: +2:37
--         goto -> bb7;                     // scope 0 at $DIR/match-arm-scopes.rs:+1:5: +4:6
-+         goto -> bb4;                     // scope 0 at $DIR/match-arm-scopes.rs:+1:5: +4:6
+          StorageDead(_13);                // scope 0 at $DIR/match_arm_scopes.rs:+2:72: +2:73
+          StorageDead(_12);                // scope 0 at $DIR/match_arm_scopes.rs:+2:72: +2:73
+-         FakeRead(ForMatchGuard, _3);     // scope 0 at $DIR/match_arm_scopes.rs:+2:72: +2:73
+-         FakeRead(ForMatchGuard, _4);     // scope 0 at $DIR/match_arm_scopes.rs:+2:72: +2:73
+-         FakeRead(ForGuardBinding, _6);   // scope 0 at $DIR/match_arm_scopes.rs:+2:72: +2:73
+-         FakeRead(ForGuardBinding, _8);   // scope 0 at $DIR/match_arm_scopes.rs:+2:72: +2:73
+          StorageLive(_5);                 // scope 0 at $DIR/match_arm_scopes.rs:+2:26: +2:27
+          _5 = (_2.0: bool);               // scope 0 at $DIR/match_arm_scopes.rs:+2:26: +2:27
+          StorageLive(_7);                 // scope 0 at $DIR/match_arm_scopes.rs:+2:36: +2:37
+          _7 = move (_2.2: std::string::String); // scope 0 at $DIR/match_arm_scopes.rs:+2:36: +2:37
+-         goto -> bb7;                     // scope 0 at $DIR/match_arm_scopes.rs:+1:5: +4:6
++         goto -> bb4;                     // scope 0 at $DIR/match_arm_scopes.rs:+1:5: +4:6
       }
   
 -     bb17: {
 +     bb14: {
-          StorageDead(_13);                // scope 0 at $DIR/match-arm-scopes.rs:+2:72: +2:73
-          StorageDead(_12);                // scope 0 at $DIR/match-arm-scopes.rs:+2:72: +2:73
-          StorageDead(_8);                 // scope 0 at $DIR/match-arm-scopes.rs:+2:77: +2:78
-          StorageDead(_6);                 // scope 0 at $DIR/match-arm-scopes.rs:+2:77: +2:78
--         falseEdge -> [real: bb4, imaginary: bb5]; // scope 0 at $DIR/match-arm-scopes.rs:+2:42: +2:73
-+         goto -> bb2;                     // scope 0 at $DIR/match-arm-scopes.rs:+2:42: +2:73
+          StorageDead(_13);                // scope 0 at $DIR/match_arm_scopes.rs:+2:72: +2:73
+          StorageDead(_12);                // scope 0 at $DIR/match_arm_scopes.rs:+2:72: +2:73
+          StorageDead(_8);                 // scope 0 at $DIR/match_arm_scopes.rs:+2:77: +2:78
+          StorageDead(_6);                 // scope 0 at $DIR/match_arm_scopes.rs:+2:77: +2:78
+-         falseEdge -> [real: bb4, imaginary: bb5]; // scope 0 at $DIR/match_arm_scopes.rs:+2:42: +2:73
++         goto -> bb2;                     // scope 0 at $DIR/match_arm_scopes.rs:+2:42: +2:73
       }
   
 -     bb18: {
 +     bb15: {
-          StorageDead(_7);                 // scope 0 at $DIR/match-arm-scopes.rs:+2:77: +2:78
-          StorageDead(_5);                 // scope 0 at $DIR/match-arm-scopes.rs:+2:77: +2:78
-          StorageDead(_8);                 // scope 0 at $DIR/match-arm-scopes.rs:+2:77: +2:78
-          StorageDead(_6);                 // scope 0 at $DIR/match-arm-scopes.rs:+2:77: +2:78
--         goto -> bb22;                    // scope 0 at $DIR/match-arm-scopes.rs:+2:77: +2:78
-+         goto -> bb19;                    // scope 0 at $DIR/match-arm-scopes.rs:+2:77: +2:78
+          StorageDead(_7);                 // scope 0 at $DIR/match_arm_scopes.rs:+2:77: +2:78
+          StorageDead(_5);                 // scope 0 at $DIR/match_arm_scopes.rs:+2:77: +2:78
+          StorageDead(_8);                 // scope 0 at $DIR/match_arm_scopes.rs:+2:77: +2:78
+          StorageDead(_6);                 // scope 0 at $DIR/match_arm_scopes.rs:+2:77: +2:78
+-         goto -> bb22;                    // scope 0 at $DIR/match_arm_scopes.rs:+2:77: +2:78
++         goto -> bb19;                    // scope 0 at $DIR/match_arm_scopes.rs:+2:77: +2:78
       }
   
 -     bb19: {
 +     bb16: {
-          _0 = const 2_i32;                // scope 2 at $DIR/match-arm-scopes.rs:+3:41: +3:42
--         drop(_16) -> [return: bb21, unwind: bb25]; // scope 0 at $DIR/match-arm-scopes.rs:+3:41: +3:42
-+         drop(_16) -> [return: bb18, unwind: bb22]; // scope 0 at $DIR/match-arm-scopes.rs:+3:41: +3:42
+          _0 = const 2_i32;                // scope 2 at $DIR/match_arm_scopes.rs:+3:41: +3:42
+-         drop(_16) -> [return: bb21, unwind: bb25]; // scope 0 at $DIR/match_arm_scopes.rs:+3:41: +3:42
++         drop(_16) -> [return: bb18, unwind: bb22]; // scope 0 at $DIR/match_arm_scopes.rs:+3:41: +3:42
       }
   
 -     bb20: {
 +     bb17: {
-          StorageLive(_15);                // scope 0 at $DIR/match-arm-scopes.rs:+3:16: +3:17
-          _15 = (_2.1: bool);              // scope 0 at $DIR/match-arm-scopes.rs:+3:16: +3:17
-          StorageLive(_16);                // scope 0 at $DIR/match-arm-scopes.rs:+3:19: +3:20
-          _16 = move (_2.2: std::string::String); // scope 0 at $DIR/match-arm-scopes.rs:+3:19: +3:20
--         goto -> bb19;                    // scope 0 at $DIR/match-arm-scopes.rs:+1:5: +4:6
-+         goto -> bb16;                    // scope 0 at $DIR/match-arm-scopes.rs:+1:5: +4:6
+          StorageLive(_15);                // scope 0 at $DIR/match_arm_scopes.rs:+3:16: +3:17
+          _15 = (_2.1: bool);              // scope 0 at $DIR/match_arm_scopes.rs:+3:16: +3:17
+          StorageLive(_16);                // scope 0 at $DIR/match_arm_scopes.rs:+3:19: +3:20
+          _16 = move (_2.2: std::string::String); // scope 0 at $DIR/match_arm_scopes.rs:+3:19: +3:20
+-         goto -> bb19;                    // scope 0 at $DIR/match_arm_scopes.rs:+1:5: +4:6
++         goto -> bb16;                    // scope 0 at $DIR/match_arm_scopes.rs:+1:5: +4:6
       }
   
 -     bb21: {
 +     bb18: {
-          StorageDead(_16);                // scope 0 at $DIR/match-arm-scopes.rs:+3:41: +3:42
-          StorageDead(_15);                // scope 0 at $DIR/match-arm-scopes.rs:+3:41: +3:42
--         goto -> bb22;                    // scope 0 at $DIR/match-arm-scopes.rs:+3:41: +3:42
-+         goto -> bb19;                    // scope 0 at $DIR/match-arm-scopes.rs:+3:41: +3:42
+          StorageDead(_16);                // scope 0 at $DIR/match_arm_scopes.rs:+3:41: +3:42
+          StorageDead(_15);                // scope 0 at $DIR/match_arm_scopes.rs:+3:41: +3:42
+-         goto -> bb22;                    // scope 0 at $DIR/match_arm_scopes.rs:+3:41: +3:42
++         goto -> bb19;                    // scope 0 at $DIR/match_arm_scopes.rs:+3:41: +3:42
       }
   
 -     bb22: {
--         drop(_2) -> [return: bb24, unwind: bb26]; // scope 0 at $DIR/match-arm-scopes.rs:+5:1: +5:2
+-         drop(_2) -> [return: bb24, unwind: bb26]; // scope 0 at $DIR/match_arm_scopes.rs:+5:1: +5:2
 +     bb19: {
-+         goto -> bb26;                    // scope 0 at $DIR/match-arm-scopes.rs:+5:1: +5:2
++         goto -> bb26;                    // scope 0 at $DIR/match_arm_scopes.rs:+5:1: +5:2
       }
   
 -     bb23: {
 +     bb20: {
-          StorageDead(_8);                 // scope 0 at $DIR/match-arm-scopes.rs:+2:77: +2:78
-          StorageDead(_6);                 // scope 0 at $DIR/match-arm-scopes.rs:+2:77: +2:78
--         drop(_2) -> [return: bb24, unwind: bb26]; // scope 0 at $DIR/match-arm-scopes.rs:+5:1: +5:2
-+         drop(_2) -> [return: bb21, unwind: bb23]; // scope 0 at $DIR/match-arm-scopes.rs:+5:1: +5:2
+          StorageDead(_8);                 // scope 0 at $DIR/match_arm_scopes.rs:+2:77: +2:78
+          StorageDead(_6);                 // scope 0 at $DIR/match_arm_scopes.rs:+2:77: +2:78
+-         drop(_2) -> [return: bb24, unwind: bb26]; // scope 0 at $DIR/match_arm_scopes.rs:+5:1: +5:2
++         drop(_2) -> [return: bb21, unwind: bb23]; // scope 0 at $DIR/match_arm_scopes.rs:+5:1: +5:2
       }
   
 -     bb24: {
 +     bb21: {
-          return;                          // scope 0 at $DIR/match-arm-scopes.rs:+5:2: +5:2
+          return;                          // scope 0 at $DIR/match_arm_scopes.rs:+5:2: +5:2
       }
   
 -     bb25 (cleanup): {
--         drop(_2) -> bb26;                // scope 0 at $DIR/match-arm-scopes.rs:+5:1: +5:2
+-         drop(_2) -> bb26;                // scope 0 at $DIR/match_arm_scopes.rs:+5:1: +5:2
 +     bb22 (cleanup): {
-+         goto -> bb27;                    // scope 0 at $DIR/match-arm-scopes.rs:+5:1: +5:2
++         goto -> bb27;                    // scope 0 at $DIR/match_arm_scopes.rs:+5:1: +5:2
       }
   
 -     bb26 (cleanup): {
 +     bb23 (cleanup): {
-          resume;                          // scope 0 at $DIR/match-arm-scopes.rs:+0:1: +5:2
+          resume;                          // scope 0 at $DIR/match_arm_scopes.rs:+0:1: +5:2
 +     }
 + 
 +     bb24: {
-+         goto -> bb21;                    // scope 0 at $DIR/match-arm-scopes.rs:+5:1: +5:2
++         goto -> bb21;                    // scope 0 at $DIR/match_arm_scopes.rs:+5:1: +5:2
 +     }
 + 
 +     bb25 (cleanup): {
-+         goto -> bb23;                    // scope 0 at $DIR/match-arm-scopes.rs:+5:1: +5:2
++         goto -> bb23;                    // scope 0 at $DIR/match_arm_scopes.rs:+5:1: +5:2
 +     }
 + 
 +     bb26: {
-+         goto -> bb24;                    // scope 0 at $DIR/match-arm-scopes.rs:+5:1: +5:2
++         goto -> bb24;                    // scope 0 at $DIR/match_arm_scopes.rs:+5:1: +5:2
 +     }
 + 
 +     bb27 (cleanup): {
-+         goto -> bb23;                    // scope 0 at $DIR/match-arm-scopes.rs:+5:1: +5:2
++         goto -> bb23;                    // scope 0 at $DIR/match_arm_scopes.rs:+5:1: +5:2
       }
   }
   
diff --git a/src/test/mir-opt/match-arm-scopes.rs b/src/test/mir-opt/match_arm_scopes.rs
similarity index 100%
rename from src/test/mir-opt/match-arm-scopes.rs
rename to src/test/mir-opt/match_arm_scopes.rs
diff --git a/src/test/mir-opt/nll/named-lifetimes-basic.rs b/src/test/mir-opt/nll/named_lifetimes_basic.rs
similarity index 100%
rename from src/test/mir-opt/nll/named-lifetimes-basic.rs
rename to src/test/mir-opt/nll/named_lifetimes_basic.rs
diff --git a/src/test/mir-opt/nll/named_lifetimes_basic.use_x.nll.0.mir b/src/test/mir-opt/nll/named_lifetimes_basic.use_x.nll.0.mir
index 0ab9d712d9f6..6cd6d8b77959 100644
--- a/src/test/mir-opt/nll/named_lifetimes_basic.use_x.nll.0.mir
+++ b/src/test/mir-opt/nll/named_lifetimes_basic.use_x.nll.0.mir
@@ -24,24 +24,24 @@
 | '_#2r live at {bb0[0..=1]}
 | '_#3r live at {bb0[0..=1]}
 | '_#4r live at {bb0[0..=1]}
-| '_#1r: '_#5r due to BoringNoLocation at All($DIR/named-lifetimes-basic.rs:12:26: 12:27) ($DIR/named-lifetimes-basic.rs:12:26: 12:27 (#0)
-| '_#1r: '_#7r due to BoringNoLocation at All($DIR/named-lifetimes-basic.rs:12:54: 12:55) ($DIR/named-lifetimes-basic.rs:12:54: 12:55 (#0)
-| '_#2r: '_#6r due to BoringNoLocation at All($DIR/named-lifetimes-basic.rs:12:42: 12:43) ($DIR/named-lifetimes-basic.rs:12:42: 12:43 (#0)
-| '_#3r: '_#8r due to BoringNoLocation at All($DIR/named-lifetimes-basic.rs:12:66: 12:67) ($DIR/named-lifetimes-basic.rs:12:66: 12:67 (#0)
-| '_#5r: '_#1r due to BoringNoLocation at All($DIR/named-lifetimes-basic.rs:12:26: 12:27) ($DIR/named-lifetimes-basic.rs:12:26: 12:27 (#0)
-| '_#6r: '_#2r due to BoringNoLocation at All($DIR/named-lifetimes-basic.rs:12:42: 12:43) ($DIR/named-lifetimes-basic.rs:12:42: 12:43 (#0)
-| '_#7r: '_#1r due to BoringNoLocation at All($DIR/named-lifetimes-basic.rs:12:54: 12:55) ($DIR/named-lifetimes-basic.rs:12:54: 12:55 (#0)
-| '_#8r: '_#3r due to BoringNoLocation at All($DIR/named-lifetimes-basic.rs:12:66: 12:67) ($DIR/named-lifetimes-basic.rs:12:66: 12:67 (#0)
+| '_#1r: '_#5r due to BoringNoLocation at All($DIR/named_lifetimes_basic.rs:12:26: 12:27) ($DIR/named_lifetimes_basic.rs:12:26: 12:27 (#0)
+| '_#1r: '_#7r due to BoringNoLocation at All($DIR/named_lifetimes_basic.rs:12:54: 12:55) ($DIR/named_lifetimes_basic.rs:12:54: 12:55 (#0)
+| '_#2r: '_#6r due to BoringNoLocation at All($DIR/named_lifetimes_basic.rs:12:42: 12:43) ($DIR/named_lifetimes_basic.rs:12:42: 12:43 (#0)
+| '_#3r: '_#8r due to BoringNoLocation at All($DIR/named_lifetimes_basic.rs:12:66: 12:67) ($DIR/named_lifetimes_basic.rs:12:66: 12:67 (#0)
+| '_#5r: '_#1r due to BoringNoLocation at All($DIR/named_lifetimes_basic.rs:12:26: 12:27) ($DIR/named_lifetimes_basic.rs:12:26: 12:27 (#0)
+| '_#6r: '_#2r due to BoringNoLocation at All($DIR/named_lifetimes_basic.rs:12:42: 12:43) ($DIR/named_lifetimes_basic.rs:12:42: 12:43 (#0)
+| '_#7r: '_#1r due to BoringNoLocation at All($DIR/named_lifetimes_basic.rs:12:54: 12:55) ($DIR/named_lifetimes_basic.rs:12:54: 12:55 (#0)
+| '_#8r: '_#3r due to BoringNoLocation at All($DIR/named_lifetimes_basic.rs:12:66: 12:67) ($DIR/named_lifetimes_basic.rs:12:66: 12:67 (#0)
 |
 fn use_x(_1: &'_#5r mut i32, _2: &'_#6r u32, _3: &'_#7r u32, _4: &'_#8r u32) -> bool {
-    debug w => _1;                       // in scope 0 at $DIR/named-lifetimes-basic.rs:+0:26: +0:27
-    debug x => _2;                       // in scope 0 at $DIR/named-lifetimes-basic.rs:+0:42: +0:43
-    debug y => _3;                       // in scope 0 at $DIR/named-lifetimes-basic.rs:+0:54: +0:55
-    debug z => _4;                       // in scope 0 at $DIR/named-lifetimes-basic.rs:+0:66: +0:67
-    let mut _0: bool;                    // return place in scope 0 at $DIR/named-lifetimes-basic.rs:+0:81: +0:85
+    debug w => _1;                       // in scope 0 at $DIR/named_lifetimes_basic.rs:+0:26: +0:27
+    debug x => _2;                       // in scope 0 at $DIR/named_lifetimes_basic.rs:+0:42: +0:43
+    debug y => _3;                       // in scope 0 at $DIR/named_lifetimes_basic.rs:+0:54: +0:55
+    debug z => _4;                       // in scope 0 at $DIR/named_lifetimes_basic.rs:+0:66: +0:67
+    let mut _0: bool;                    // return place in scope 0 at $DIR/named_lifetimes_basic.rs:+0:81: +0:85
 
     bb0: {
-        _0 = const ConstValue(Scalar(0x01): bool); // bb0[0]: scope 0 at $DIR/named-lifetimes-basic.rs:+0:88: +0:92
-        return;                          // bb0[1]: scope 0 at $DIR/named-lifetimes-basic.rs:+0:94: +0:94
+        _0 = const ConstValue(Scalar(0x01): bool); // bb0[0]: scope 0 at $DIR/named_lifetimes_basic.rs:+0:88: +0:92
+        return;                          // bb0[1]: scope 0 at $DIR/named_lifetimes_basic.rs:+0:94: +0:94
     }
 }
diff --git a/src/test/mir-opt/nll/region_subtyping_basic.main.nll.0.32bit.mir b/src/test/mir-opt/nll/region_subtyping_basic.main.nll.0.32bit.mir
index 36705d18e016..3e3fda6141ae 100644
--- a/src/test/mir-opt/nll/region_subtyping_basic.main.nll.0.32bit.mir
+++ b/src/test/mir-opt/nll/region_subtyping_basic.main.nll.0.32bit.mir
@@ -17,95 +17,95 @@
 | '_#2r live at {bb1[0]}
 | '_#3r live at {bb1[1..=3]}
 | '_#4r live at {bb1[4..=7], bb2[0..=2]}
-| '_#2r: '_#3r due to Assignment at Single(bb1[0]) ($DIR/region-subtyping-basic.rs:18:13: 18:18 (#0)
-| '_#3r: '_#4r due to Assignment at Single(bb1[3]) ($DIR/region-subtyping-basic.rs:19:13: 19:14 (#0)
+| '_#2r: '_#3r due to Assignment at Single(bb1[0]) ($DIR/region_subtyping_basic.rs:18:13: 18:18 (#0)
+| '_#3r: '_#4r due to Assignment at Single(bb1[3]) ($DIR/region_subtyping_basic.rs:19:13: 19:14 (#0)
 |
 fn main() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/region-subtyping-basic.rs:+0:11: +0:11
-    let mut _1: [usize; Const { ty: usize, kind: Value(Leaf(0x00000003)) }]; // in scope 0 at $DIR/region-subtyping-basic.rs:+1:9: +1:14
-    let _3: usize;                       // in scope 0 at $DIR/region-subtyping-basic.rs:+2:16: +2:17
-    let mut _4: usize;                   // in scope 0 at $DIR/region-subtyping-basic.rs:+2:14: +2:18
-    let mut _5: bool;                    // in scope 0 at $DIR/region-subtyping-basic.rs:+2:14: +2:18
-    let mut _7: bool;                    // in scope 0 at $DIR/region-subtyping-basic.rs:+4:8: +4:12
-    let _8: bool;                        // in scope 0 at $DIR/region-subtyping-basic.rs:+5:9: +5:18
-    let mut _9: usize;                   // in scope 0 at $DIR/region-subtyping-basic.rs:+5:15: +5:17
-    let _10: bool;                       // in scope 0 at $DIR/region-subtyping-basic.rs:+7:9: +7:18
+    let mut _0: ();                      // return place in scope 0 at $DIR/region_subtyping_basic.rs:+0:11: +0:11
+    let mut _1: [usize; Const { ty: usize, kind: Value(Leaf(0x00000003)) }]; // in scope 0 at $DIR/region_subtyping_basic.rs:+1:9: +1:14
+    let _3: usize;                       // in scope 0 at $DIR/region_subtyping_basic.rs:+2:16: +2:17
+    let mut _4: usize;                   // in scope 0 at $DIR/region_subtyping_basic.rs:+2:14: +2:18
+    let mut _5: bool;                    // in scope 0 at $DIR/region_subtyping_basic.rs:+2:14: +2:18
+    let mut _7: bool;                    // in scope 0 at $DIR/region_subtyping_basic.rs:+4:8: +4:12
+    let _8: bool;                        // in scope 0 at $DIR/region_subtyping_basic.rs:+5:9: +5:18
+    let mut _9: usize;                   // in scope 0 at $DIR/region_subtyping_basic.rs:+5:15: +5:17
+    let _10: bool;                       // in scope 0 at $DIR/region_subtyping_basic.rs:+7:9: +7:18
     scope 1 {
-        debug v => _1;                   // in scope 1 at $DIR/region-subtyping-basic.rs:+1:9: +1:14
-        let _2: &'_#3r usize;            // in scope 1 at $DIR/region-subtyping-basic.rs:+2:9: +2:10
+        debug v => _1;                   // in scope 1 at $DIR/region_subtyping_basic.rs:+1:9: +1:14
+        let _2: &'_#3r usize;            // in scope 1 at $DIR/region_subtyping_basic.rs:+2:9: +2:10
         scope 2 {
-            debug p => _2;               // in scope 2 at $DIR/region-subtyping-basic.rs:+2:9: +2:10
-            let _6: &'_#4r usize;        // in scope 2 at $DIR/region-subtyping-basic.rs:+3:9: +3:10
+            debug p => _2;               // in scope 2 at $DIR/region_subtyping_basic.rs:+2:9: +2:10
+            let _6: &'_#4r usize;        // in scope 2 at $DIR/region_subtyping_basic.rs:+3:9: +3:10
             scope 3 {
-                debug q => _6;           // in scope 3 at $DIR/region-subtyping-basic.rs:+3:9: +3:10
+                debug q => _6;           // in scope 3 at $DIR/region_subtyping_basic.rs:+3:9: +3:10
             }
         }
     }
 
     bb0: {
-        StorageLive(_1);                 // bb0[0]: scope 0 at $DIR/region-subtyping-basic.rs:+1:9: +1:14
-        _1 = [const ConstValue(Scalar(0x00000001): usize), const ConstValue(Scalar(0x00000002): usize), const ConstValue(Scalar(0x00000003): usize)]; // bb0[1]: scope 0 at $DIR/region-subtyping-basic.rs:+1:17: +1:26
-        FakeRead(ForLet(None), _1);      // bb0[2]: scope 0 at $DIR/region-subtyping-basic.rs:+1:9: +1:14
-        StorageLive(_2);                 // bb0[3]: scope 1 at $DIR/region-subtyping-basic.rs:+2:9: +2:10
-        StorageLive(_3);                 // bb0[4]: scope 1 at $DIR/region-subtyping-basic.rs:+2:16: +2:17
-        _3 = const ConstValue(Scalar(0x00000000): usize); // bb0[5]: scope 1 at $DIR/region-subtyping-basic.rs:+2:16: +2:17
-        _4 = Len(_1);                    // bb0[6]: scope 1 at $DIR/region-subtyping-basic.rs:+2:14: +2:18
-        _5 = Lt(_3, _4);                 // bb0[7]: scope 1 at $DIR/region-subtyping-basic.rs:+2:14: +2:18
-        assert(move _5, "index out of bounds: the length is {} but the index is {}", move _4, _3) -> [success: bb1, unwind: bb7]; // bb0[8]: scope 1 at $DIR/region-subtyping-basic.rs:+2:14: +2:18
+        StorageLive(_1);                 // bb0[0]: scope 0 at $DIR/region_subtyping_basic.rs:+1:9: +1:14
+        _1 = [const ConstValue(Scalar(0x00000001): usize), const ConstValue(Scalar(0x00000002): usize), const ConstValue(Scalar(0x00000003): usize)]; // bb0[1]: scope 0 at $DIR/region_subtyping_basic.rs:+1:17: +1:26
+        FakeRead(ForLet(None), _1);      // bb0[2]: scope 0 at $DIR/region_subtyping_basic.rs:+1:9: +1:14
+        StorageLive(_2);                 // bb0[3]: scope 1 at $DIR/region_subtyping_basic.rs:+2:9: +2:10
+        StorageLive(_3);                 // bb0[4]: scope 1 at $DIR/region_subtyping_basic.rs:+2:16: +2:17
+        _3 = const ConstValue(Scalar(0x00000000): usize); // bb0[5]: scope 1 at $DIR/region_subtyping_basic.rs:+2:16: +2:17
+        _4 = Len(_1);                    // bb0[6]: scope 1 at $DIR/region_subtyping_basic.rs:+2:14: +2:18
+        _5 = Lt(_3, _4);                 // bb0[7]: scope 1 at $DIR/region_subtyping_basic.rs:+2:14: +2:18
+        assert(move _5, "index out of bounds: the length is {} but the index is {}", move _4, _3) -> [success: bb1, unwind: bb7]; // bb0[8]: scope 1 at $DIR/region_subtyping_basic.rs:+2:14: +2:18
     }
 
     bb1: {
-        _2 = &'_#2r _1[_3];              // bb1[0]: scope 1 at $DIR/region-subtyping-basic.rs:+2:13: +2:18
-        FakeRead(ForLet(None), _2);      // bb1[1]: scope 1 at $DIR/region-subtyping-basic.rs:+2:9: +2:10
-        StorageLive(_6);                 // bb1[2]: scope 2 at $DIR/region-subtyping-basic.rs:+3:9: +3:10
-        _6 = _2;                         // bb1[3]: scope 2 at $DIR/region-subtyping-basic.rs:+3:13: +3:14
-        FakeRead(ForLet(None), _6);      // bb1[4]: scope 2 at $DIR/region-subtyping-basic.rs:+3:9: +3:10
-        StorageLive(_7);                 // bb1[5]: scope 3 at $DIR/region-subtyping-basic.rs:+4:8: +4:12
-        _7 = const ConstValue(Scalar(0x01): bool); // bb1[6]: scope 3 at $DIR/region-subtyping-basic.rs:+4:8: +4:12
-        switchInt(move _7) -> [ConstValue(Scalar(0x00): bool): bb4, otherwise: bb2]; // bb1[7]: scope 3 at $DIR/region-subtyping-basic.rs:+4:8: +4:12
+        _2 = &'_#2r _1[_3];              // bb1[0]: scope 1 at $DIR/region_subtyping_basic.rs:+2:13: +2:18
+        FakeRead(ForLet(None), _2);      // bb1[1]: scope 1 at $DIR/region_subtyping_basic.rs:+2:9: +2:10
+        StorageLive(_6);                 // bb1[2]: scope 2 at $DIR/region_subtyping_basic.rs:+3:9: +3:10
+        _6 = _2;                         // bb1[3]: scope 2 at $DIR/region_subtyping_basic.rs:+3:13: +3:14
+        FakeRead(ForLet(None), _6);      // bb1[4]: scope 2 at $DIR/region_subtyping_basic.rs:+3:9: +3:10
+        StorageLive(_7);                 // bb1[5]: scope 3 at $DIR/region_subtyping_basic.rs:+4:8: +4:12
+        _7 = const ConstValue(Scalar(0x01): bool); // bb1[6]: scope 3 at $DIR/region_subtyping_basic.rs:+4:8: +4:12
+        switchInt(move _7) -> [ConstValue(Scalar(0x00): bool): bb4, otherwise: bb2]; // bb1[7]: scope 3 at $DIR/region_subtyping_basic.rs:+4:8: +4:12
     }
 
     bb2: {
-        StorageLive(_8);                 // bb2[0]: scope 3 at $DIR/region-subtyping-basic.rs:+5:9: +5:18
-        StorageLive(_9);                 // bb2[1]: scope 3 at $DIR/region-subtyping-basic.rs:+5:15: +5:17
-        _9 = (*_6);                      // bb2[2]: scope 3 at $DIR/region-subtyping-basic.rs:+5:15: +5:17
-        _8 = ConstValue(ZeroSized: fn(usize) -> bool {use_x})(move _9) -> [return: bb3, unwind: bb7]; // bb2[3]: scope 3 at $DIR/region-subtyping-basic.rs:+5:9: +5:18
+        StorageLive(_8);                 // bb2[0]: scope 3 at $DIR/region_subtyping_basic.rs:+5:9: +5:18
+        StorageLive(_9);                 // bb2[1]: scope 3 at $DIR/region_subtyping_basic.rs:+5:15: +5:17
+        _9 = (*_6);                      // bb2[2]: scope 3 at $DIR/region_subtyping_basic.rs:+5:15: +5:17
+        _8 = ConstValue(ZeroSized: fn(usize) -> bool {use_x})(move _9) -> [return: bb3, unwind: bb7]; // bb2[3]: scope 3 at $DIR/region_subtyping_basic.rs:+5:9: +5:18
                                          // mir::Constant
-                                         // + span: $DIR/region-subtyping-basic.rs:21:9: 21:14
+                                         // + span: $DIR/region_subtyping_basic.rs:21:9: 21:14
                                          // + literal: Const { ty: fn(usize) -> bool {use_x}, val: Value(<ZST>) }
     }
 
     bb3: {
-        StorageDead(_9);                 // bb3[0]: scope 3 at $DIR/region-subtyping-basic.rs:+5:17: +5:18
-        StorageDead(_8);                 // bb3[1]: scope 3 at $DIR/region-subtyping-basic.rs:+5:18: +5:19
-        _0 = const ConstValue(ZeroSized: ()); // bb3[2]: scope 3 at $DIR/region-subtyping-basic.rs:+4:13: +6:6
-        goto -> bb6;                     // bb3[3]: scope 3 at $DIR/region-subtyping-basic.rs:+4:5: +8:6
+        StorageDead(_9);                 // bb3[0]: scope 3 at $DIR/region_subtyping_basic.rs:+5:17: +5:18
+        StorageDead(_8);                 // bb3[1]: scope 3 at $DIR/region_subtyping_basic.rs:+5:18: +5:19
+        _0 = const ConstValue(ZeroSized: ()); // bb3[2]: scope 3 at $DIR/region_subtyping_basic.rs:+4:13: +6:6
+        goto -> bb6;                     // bb3[3]: scope 3 at $DIR/region_subtyping_basic.rs:+4:5: +8:6
     }
 
     bb4: {
-        StorageLive(_10);                // bb4[0]: scope 3 at $DIR/region-subtyping-basic.rs:+7:9: +7:18
-        _10 = ConstValue(ZeroSized: fn(usize) -> bool {use_x})(const ConstValue(Scalar(0x00000016): usize)) -> [return: bb5, unwind: bb7]; // bb4[1]: scope 3 at $DIR/region-subtyping-basic.rs:+7:9: +7:18
+        StorageLive(_10);                // bb4[0]: scope 3 at $DIR/region_subtyping_basic.rs:+7:9: +7:18
+        _10 = ConstValue(ZeroSized: fn(usize) -> bool {use_x})(const ConstValue(Scalar(0x00000016): usize)) -> [return: bb5, unwind: bb7]; // bb4[1]: scope 3 at $DIR/region_subtyping_basic.rs:+7:9: +7:18
                                          // mir::Constant
-                                         // + span: $DIR/region-subtyping-basic.rs:23:9: 23:14
+                                         // + span: $DIR/region_subtyping_basic.rs:23:9: 23:14
                                          // + literal: Const { ty: fn(usize) -> bool {use_x}, val: Value(<ZST>) }
     }
 
     bb5: {
-        StorageDead(_10);                // bb5[0]: scope 3 at $DIR/region-subtyping-basic.rs:+7:18: +7:19
-        _0 = const ConstValue(ZeroSized: ()); // bb5[1]: scope 3 at $DIR/region-subtyping-basic.rs:+6:12: +8:6
-        goto -> bb6;                     // bb5[2]: scope 3 at $DIR/region-subtyping-basic.rs:+4:5: +8:6
+        StorageDead(_10);                // bb5[0]: scope 3 at $DIR/region_subtyping_basic.rs:+7:18: +7:19
+        _0 = const ConstValue(ZeroSized: ()); // bb5[1]: scope 3 at $DIR/region_subtyping_basic.rs:+6:12: +8:6
+        goto -> bb6;                     // bb5[2]: scope 3 at $DIR/region_subtyping_basic.rs:+4:5: +8:6
     }
 
     bb6: {
-        StorageDead(_7);                 // bb6[0]: scope 3 at $DIR/region-subtyping-basic.rs:+8:5: +8:6
-        StorageDead(_6);                 // bb6[1]: scope 2 at $DIR/region-subtyping-basic.rs:+9:1: +9:2
-        StorageDead(_3);                 // bb6[2]: scope 1 at $DIR/region-subtyping-basic.rs:+9:1: +9:2
-        StorageDead(_2);                 // bb6[3]: scope 1 at $DIR/region-subtyping-basic.rs:+9:1: +9:2
-        StorageDead(_1);                 // bb6[4]: scope 0 at $DIR/region-subtyping-basic.rs:+9:1: +9:2
-        return;                          // bb6[5]: scope 0 at $DIR/region-subtyping-basic.rs:+9:2: +9:2
+        StorageDead(_7);                 // bb6[0]: scope 3 at $DIR/region_subtyping_basic.rs:+8:5: +8:6
+        StorageDead(_6);                 // bb6[1]: scope 2 at $DIR/region_subtyping_basic.rs:+9:1: +9:2
+        StorageDead(_3);                 // bb6[2]: scope 1 at $DIR/region_subtyping_basic.rs:+9:1: +9:2
+        StorageDead(_2);                 // bb6[3]: scope 1 at $DIR/region_subtyping_basic.rs:+9:1: +9:2
+        StorageDead(_1);                 // bb6[4]: scope 0 at $DIR/region_subtyping_basic.rs:+9:1: +9:2
+        return;                          // bb6[5]: scope 0 at $DIR/region_subtyping_basic.rs:+9:2: +9:2
     }
 
     bb7 (cleanup): {
-        resume;                          // bb7[0]: scope 0 at $DIR/region-subtyping-basic.rs:+0:1: +9:2
+        resume;                          // bb7[0]: scope 0 at $DIR/region_subtyping_basic.rs:+0:1: +9:2
     }
 }
diff --git a/src/test/mir-opt/nll/region_subtyping_basic.main.nll.0.64bit.mir b/src/test/mir-opt/nll/region_subtyping_basic.main.nll.0.64bit.mir
index 4f6256a67f46..39a53702a4cb 100644
--- a/src/test/mir-opt/nll/region_subtyping_basic.main.nll.0.64bit.mir
+++ b/src/test/mir-opt/nll/region_subtyping_basic.main.nll.0.64bit.mir
@@ -17,95 +17,95 @@
 | '_#2r live at {bb1[0]}
 | '_#3r live at {bb1[1..=3]}
 | '_#4r live at {bb1[4..=7], bb2[0..=2]}
-| '_#2r: '_#3r due to Assignment at Single(bb1[0]) ($DIR/region-subtyping-basic.rs:18:13: 18:18 (#0)
-| '_#3r: '_#4r due to Assignment at Single(bb1[3]) ($DIR/region-subtyping-basic.rs:19:13: 19:14 (#0)
+| '_#2r: '_#3r due to Assignment at Single(bb1[0]) ($DIR/region_subtyping_basic.rs:18:13: 18:18 (#0)
+| '_#3r: '_#4r due to Assignment at Single(bb1[3]) ($DIR/region_subtyping_basic.rs:19:13: 19:14 (#0)
 |
 fn main() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/region-subtyping-basic.rs:+0:11: +0:11
-    let mut _1: [usize; Const { ty: usize, kind: Value(Leaf(0x0000000000000003)) }]; // in scope 0 at $DIR/region-subtyping-basic.rs:+1:9: +1:14
-    let _3: usize;                       // in scope 0 at $DIR/region-subtyping-basic.rs:+2:16: +2:17
-    let mut _4: usize;                   // in scope 0 at $DIR/region-subtyping-basic.rs:+2:14: +2:18
-    let mut _5: bool;                    // in scope 0 at $DIR/region-subtyping-basic.rs:+2:14: +2:18
-    let mut _7: bool;                    // in scope 0 at $DIR/region-subtyping-basic.rs:+4:8: +4:12
-    let _8: bool;                        // in scope 0 at $DIR/region-subtyping-basic.rs:+5:9: +5:18
-    let mut _9: usize;                   // in scope 0 at $DIR/region-subtyping-basic.rs:+5:15: +5:17
-    let _10: bool;                       // in scope 0 at $DIR/region-subtyping-basic.rs:+7:9: +7:18
+    let mut _0: ();                      // return place in scope 0 at $DIR/region_subtyping_basic.rs:+0:11: +0:11
+    let mut _1: [usize; Const { ty: usize, kind: Value(Leaf(0x0000000000000003)) }]; // in scope 0 at $DIR/region_subtyping_basic.rs:+1:9: +1:14
+    let _3: usize;                       // in scope 0 at $DIR/region_subtyping_basic.rs:+2:16: +2:17
+    let mut _4: usize;                   // in scope 0 at $DIR/region_subtyping_basic.rs:+2:14: +2:18
+    let mut _5: bool;                    // in scope 0 at $DIR/region_subtyping_basic.rs:+2:14: +2:18
+    let mut _7: bool;                    // in scope 0 at $DIR/region_subtyping_basic.rs:+4:8: +4:12
+    let _8: bool;                        // in scope 0 at $DIR/region_subtyping_basic.rs:+5:9: +5:18
+    let mut _9: usize;                   // in scope 0 at $DIR/region_subtyping_basic.rs:+5:15: +5:17
+    let _10: bool;                       // in scope 0 at $DIR/region_subtyping_basic.rs:+7:9: +7:18
     scope 1 {
-        debug v => _1;                   // in scope 1 at $DIR/region-subtyping-basic.rs:+1:9: +1:14
-        let _2: &'_#3r usize;            // in scope 1 at $DIR/region-subtyping-basic.rs:+2:9: +2:10
+        debug v => _1;                   // in scope 1 at $DIR/region_subtyping_basic.rs:+1:9: +1:14
+        let _2: &'_#3r usize;            // in scope 1 at $DIR/region_subtyping_basic.rs:+2:9: +2:10
         scope 2 {
-            debug p => _2;               // in scope 2 at $DIR/region-subtyping-basic.rs:+2:9: +2:10
-            let _6: &'_#4r usize;        // in scope 2 at $DIR/region-subtyping-basic.rs:+3:9: +3:10
+            debug p => _2;               // in scope 2 at $DIR/region_subtyping_basic.rs:+2:9: +2:10
+            let _6: &'_#4r usize;        // in scope 2 at $DIR/region_subtyping_basic.rs:+3:9: +3:10
             scope 3 {
-                debug q => _6;           // in scope 3 at $DIR/region-subtyping-basic.rs:+3:9: +3:10
+                debug q => _6;           // in scope 3 at $DIR/region_subtyping_basic.rs:+3:9: +3:10
             }
         }
     }
 
     bb0: {
-        StorageLive(_1);                 // bb0[0]: scope 0 at $DIR/region-subtyping-basic.rs:+1:9: +1:14
-        _1 = [const ConstValue(Scalar(0x0000000000000001): usize), const ConstValue(Scalar(0x0000000000000002): usize), const ConstValue(Scalar(0x0000000000000003): usize)]; // bb0[1]: scope 0 at $DIR/region-subtyping-basic.rs:+1:17: +1:26
-        FakeRead(ForLet(None), _1);      // bb0[2]: scope 0 at $DIR/region-subtyping-basic.rs:+1:9: +1:14
-        StorageLive(_2);                 // bb0[3]: scope 1 at $DIR/region-subtyping-basic.rs:+2:9: +2:10
-        StorageLive(_3);                 // bb0[4]: scope 1 at $DIR/region-subtyping-basic.rs:+2:16: +2:17
-        _3 = const ConstValue(Scalar(0x0000000000000000): usize); // bb0[5]: scope 1 at $DIR/region-subtyping-basic.rs:+2:16: +2:17
-        _4 = Len(_1);                    // bb0[6]: scope 1 at $DIR/region-subtyping-basic.rs:+2:14: +2:18
-        _5 = Lt(_3, _4);                 // bb0[7]: scope 1 at $DIR/region-subtyping-basic.rs:+2:14: +2:18
-        assert(move _5, "index out of bounds: the length is {} but the index is {}", move _4, _3) -> [success: bb1, unwind: bb7]; // bb0[8]: scope 1 at $DIR/region-subtyping-basic.rs:+2:14: +2:18
+        StorageLive(_1);                 // bb0[0]: scope 0 at $DIR/region_subtyping_basic.rs:+1:9: +1:14
+        _1 = [const ConstValue(Scalar(0x0000000000000001): usize), const ConstValue(Scalar(0x0000000000000002): usize), const ConstValue(Scalar(0x0000000000000003): usize)]; // bb0[1]: scope 0 at $DIR/region_subtyping_basic.rs:+1:17: +1:26
+        FakeRead(ForLet(None), _1);      // bb0[2]: scope 0 at $DIR/region_subtyping_basic.rs:+1:9: +1:14
+        StorageLive(_2);                 // bb0[3]: scope 1 at $DIR/region_subtyping_basic.rs:+2:9: +2:10
+        StorageLive(_3);                 // bb0[4]: scope 1 at $DIR/region_subtyping_basic.rs:+2:16: +2:17
+        _3 = const ConstValue(Scalar(0x0000000000000000): usize); // bb0[5]: scope 1 at $DIR/region_subtyping_basic.rs:+2:16: +2:17
+        _4 = Len(_1);                    // bb0[6]: scope 1 at $DIR/region_subtyping_basic.rs:+2:14: +2:18
+        _5 = Lt(_3, _4);                 // bb0[7]: scope 1 at $DIR/region_subtyping_basic.rs:+2:14: +2:18
+        assert(move _5, "index out of bounds: the length is {} but the index is {}", move _4, _3) -> [success: bb1, unwind: bb7]; // bb0[8]: scope 1 at $DIR/region_subtyping_basic.rs:+2:14: +2:18
     }
 
     bb1: {
-        _2 = &'_#2r _1[_3];              // bb1[0]: scope 1 at $DIR/region-subtyping-basic.rs:+2:13: +2:18
-        FakeRead(ForLet(None), _2);      // bb1[1]: scope 1 at $DIR/region-subtyping-basic.rs:+2:9: +2:10
-        StorageLive(_6);                 // bb1[2]: scope 2 at $DIR/region-subtyping-basic.rs:+3:9: +3:10
-        _6 = _2;                         // bb1[3]: scope 2 at $DIR/region-subtyping-basic.rs:+3:13: +3:14
-        FakeRead(ForLet(None), _6);      // bb1[4]: scope 2 at $DIR/region-subtyping-basic.rs:+3:9: +3:10
-        StorageLive(_7);                 // bb1[5]: scope 3 at $DIR/region-subtyping-basic.rs:+4:8: +4:12
-        _7 = const ConstValue(Scalar(0x01): bool); // bb1[6]: scope 3 at $DIR/region-subtyping-basic.rs:+4:8: +4:12
-        switchInt(move _7) -> [ConstValue(Scalar(0x00): bool): bb4, otherwise: bb2]; // bb1[7]: scope 3 at $DIR/region-subtyping-basic.rs:+4:8: +4:12
+        _2 = &'_#2r _1[_3];              // bb1[0]: scope 1 at $DIR/region_subtyping_basic.rs:+2:13: +2:18
+        FakeRead(ForLet(None), _2);      // bb1[1]: scope 1 at $DIR/region_subtyping_basic.rs:+2:9: +2:10
+        StorageLive(_6);                 // bb1[2]: scope 2 at $DIR/region_subtyping_basic.rs:+3:9: +3:10
+        _6 = _2;                         // bb1[3]: scope 2 at $DIR/region_subtyping_basic.rs:+3:13: +3:14
+        FakeRead(ForLet(None), _6);      // bb1[4]: scope 2 at $DIR/region_subtyping_basic.rs:+3:9: +3:10
+        StorageLive(_7);                 // bb1[5]: scope 3 at $DIR/region_subtyping_basic.rs:+4:8: +4:12
+        _7 = const ConstValue(Scalar(0x01): bool); // bb1[6]: scope 3 at $DIR/region_subtyping_basic.rs:+4:8: +4:12
+        switchInt(move _7) -> [ConstValue(Scalar(0x00): bool): bb4, otherwise: bb2]; // bb1[7]: scope 3 at $DIR/region_subtyping_basic.rs:+4:8: +4:12
     }
 
     bb2: {
-        StorageLive(_8);                 // bb2[0]: scope 3 at $DIR/region-subtyping-basic.rs:+5:9: +5:18
-        StorageLive(_9);                 // bb2[1]: scope 3 at $DIR/region-subtyping-basic.rs:+5:15: +5:17
-        _9 = (*_6);                      // bb2[2]: scope 3 at $DIR/region-subtyping-basic.rs:+5:15: +5:17
-        _8 = ConstValue(ZeroSized: fn(usize) -> bool {use_x})(move _9) -> [return: bb3, unwind: bb7]; // bb2[3]: scope 3 at $DIR/region-subtyping-basic.rs:+5:9: +5:18
+        StorageLive(_8);                 // bb2[0]: scope 3 at $DIR/region_subtyping_basic.rs:+5:9: +5:18
+        StorageLive(_9);                 // bb2[1]: scope 3 at $DIR/region_subtyping_basic.rs:+5:15: +5:17
+        _9 = (*_6);                      // bb2[2]: scope 3 at $DIR/region_subtyping_basic.rs:+5:15: +5:17
+        _8 = ConstValue(ZeroSized: fn(usize) -> bool {use_x})(move _9) -> [return: bb3, unwind: bb7]; // bb2[3]: scope 3 at $DIR/region_subtyping_basic.rs:+5:9: +5:18
                                          // mir::Constant
-                                         // + span: $DIR/region-subtyping-basic.rs:21:9: 21:14
+                                         // + span: $DIR/region_subtyping_basic.rs:21:9: 21:14
                                          // + literal: Const { ty: fn(usize) -> bool {use_x}, val: Value(<ZST>) }
     }
 
     bb3: {
-        StorageDead(_9);                 // bb3[0]: scope 3 at $DIR/region-subtyping-basic.rs:+5:17: +5:18
-        StorageDead(_8);                 // bb3[1]: scope 3 at $DIR/region-subtyping-basic.rs:+5:18: +5:19
-        _0 = const ConstValue(ZeroSized: ()); // bb3[2]: scope 3 at $DIR/region-subtyping-basic.rs:+4:13: +6:6
-        goto -> bb6;                     // bb3[3]: scope 3 at $DIR/region-subtyping-basic.rs:+4:5: +8:6
+        StorageDead(_9);                 // bb3[0]: scope 3 at $DIR/region_subtyping_basic.rs:+5:17: +5:18
+        StorageDead(_8);                 // bb3[1]: scope 3 at $DIR/region_subtyping_basic.rs:+5:18: +5:19
+        _0 = const ConstValue(ZeroSized: ()); // bb3[2]: scope 3 at $DIR/region_subtyping_basic.rs:+4:13: +6:6
+        goto -> bb6;                     // bb3[3]: scope 3 at $DIR/region_subtyping_basic.rs:+4:5: +8:6
     }
 
     bb4: {
-        StorageLive(_10);                // bb4[0]: scope 3 at $DIR/region-subtyping-basic.rs:+7:9: +7:18
-        _10 = ConstValue(ZeroSized: fn(usize) -> bool {use_x})(const ConstValue(Scalar(0x0000000000000016): usize)) -> [return: bb5, unwind: bb7]; // bb4[1]: scope 3 at $DIR/region-subtyping-basic.rs:+7:9: +7:18
+        StorageLive(_10);                // bb4[0]: scope 3 at $DIR/region_subtyping_basic.rs:+7:9: +7:18
+        _10 = ConstValue(ZeroSized: fn(usize) -> bool {use_x})(const ConstValue(Scalar(0x0000000000000016): usize)) -> [return: bb5, unwind: bb7]; // bb4[1]: scope 3 at $DIR/region_subtyping_basic.rs:+7:9: +7:18
                                          // mir::Constant
-                                         // + span: $DIR/region-subtyping-basic.rs:23:9: 23:14
+                                         // + span: $DIR/region_subtyping_basic.rs:23:9: 23:14
                                          // + literal: Const { ty: fn(usize) -> bool {use_x}, val: Value(<ZST>) }
     }
 
     bb5: {
-        StorageDead(_10);                // bb5[0]: scope 3 at $DIR/region-subtyping-basic.rs:+7:18: +7:19
-        _0 = const ConstValue(ZeroSized: ()); // bb5[1]: scope 3 at $DIR/region-subtyping-basic.rs:+6:12: +8:6
-        goto -> bb6;                     // bb5[2]: scope 3 at $DIR/region-subtyping-basic.rs:+4:5: +8:6
+        StorageDead(_10);                // bb5[0]: scope 3 at $DIR/region_subtyping_basic.rs:+7:18: +7:19
+        _0 = const ConstValue(ZeroSized: ()); // bb5[1]: scope 3 at $DIR/region_subtyping_basic.rs:+6:12: +8:6
+        goto -> bb6;                     // bb5[2]: scope 3 at $DIR/region_subtyping_basic.rs:+4:5: +8:6
     }
 
     bb6: {
-        StorageDead(_7);                 // bb6[0]: scope 3 at $DIR/region-subtyping-basic.rs:+8:5: +8:6
-        StorageDead(_6);                 // bb6[1]: scope 2 at $DIR/region-subtyping-basic.rs:+9:1: +9:2
-        StorageDead(_3);                 // bb6[2]: scope 1 at $DIR/region-subtyping-basic.rs:+9:1: +9:2
-        StorageDead(_2);                 // bb6[3]: scope 1 at $DIR/region-subtyping-basic.rs:+9:1: +9:2
-        StorageDead(_1);                 // bb6[4]: scope 0 at $DIR/region-subtyping-basic.rs:+9:1: +9:2
-        return;                          // bb6[5]: scope 0 at $DIR/region-subtyping-basic.rs:+9:2: +9:2
+        StorageDead(_7);                 // bb6[0]: scope 3 at $DIR/region_subtyping_basic.rs:+8:5: +8:6
+        StorageDead(_6);                 // bb6[1]: scope 2 at $DIR/region_subtyping_basic.rs:+9:1: +9:2
+        StorageDead(_3);                 // bb6[2]: scope 1 at $DIR/region_subtyping_basic.rs:+9:1: +9:2
+        StorageDead(_2);                 // bb6[3]: scope 1 at $DIR/region_subtyping_basic.rs:+9:1: +9:2
+        StorageDead(_1);                 // bb6[4]: scope 0 at $DIR/region_subtyping_basic.rs:+9:1: +9:2
+        return;                          // bb6[5]: scope 0 at $DIR/region_subtyping_basic.rs:+9:2: +9:2
     }
 
     bb7 (cleanup): {
-        resume;                          // bb7[0]: scope 0 at $DIR/region-subtyping-basic.rs:+0:1: +9:2
+        resume;                          // bb7[0]: scope 0 at $DIR/region_subtyping_basic.rs:+0:1: +9:2
     }
 }
diff --git a/src/test/mir-opt/nll/region-subtyping-basic.rs b/src/test/mir-opt/nll/region_subtyping_basic.rs
similarity index 100%
rename from src/test/mir-opt/nll/region-subtyping-basic.rs
rename to src/test/mir-opt/nll/region_subtyping_basic.rs
diff --git a/src/test/mir-opt/no-drop-for-inactive-variant.rs b/src/test/mir-opt/no_drop_for_inactive_variant.rs
similarity index 100%
rename from src/test/mir-opt/no-drop-for-inactive-variant.rs
rename to src/test/mir-opt/no_drop_for_inactive_variant.rs
diff --git a/src/test/mir-opt/no_drop_for_inactive_variant.unwrap.SimplifyCfg-elaborate-drops.after.mir b/src/test/mir-opt/no_drop_for_inactive_variant.unwrap.SimplifyCfg-elaborate-drops.after.mir
index 50fd98ff13a6..e708255cea43 100644
--- a/src/test/mir-opt/no_drop_for_inactive_variant.unwrap.SimplifyCfg-elaborate-drops.after.mir
+++ b/src/test/mir-opt/no_drop_for_inactive_variant.unwrap.SimplifyCfg-elaborate-drops.after.mir
@@ -1,21 +1,21 @@
 // MIR for `unwrap` after SimplifyCfg-elaborate-drops
 
 fn unwrap(_1: Option<T>) -> T {
-    debug opt => _1;                     // in scope 0 at $DIR/no-drop-for-inactive-variant.rs:+0:14: +0:17
-    let mut _0: T;                       // return place in scope 0 at $DIR/no-drop-for-inactive-variant.rs:+0:33: +0:34
-    let mut _2: isize;                   // in scope 0 at $DIR/no-drop-for-inactive-variant.rs:+2:9: +2:16
-    let _3: T;                           // in scope 0 at $DIR/no-drop-for-inactive-variant.rs:+2:14: +2:15
+    debug opt => _1;                     // in scope 0 at $DIR/no_drop_for_inactive_variant.rs:+0:14: +0:17
+    let mut _0: T;                       // return place in scope 0 at $DIR/no_drop_for_inactive_variant.rs:+0:33: +0:34
+    let mut _2: isize;                   // in scope 0 at $DIR/no_drop_for_inactive_variant.rs:+2:9: +2:16
+    let _3: T;                           // in scope 0 at $DIR/no_drop_for_inactive_variant.rs:+2:14: +2:15
     let mut _4: !;                       // in scope 0 at $SRC_DIR/std/src/panic.rs:LL:COL
-    let mut _5: isize;                   // in scope 0 at $DIR/no-drop-for-inactive-variant.rs:+5:1: +5:2
-    let mut _6: isize;                   // in scope 0 at $DIR/no-drop-for-inactive-variant.rs:+5:1: +5:2
-    let mut _7: isize;                   // in scope 0 at $DIR/no-drop-for-inactive-variant.rs:+5:1: +5:2
+    let mut _5: isize;                   // in scope 0 at $DIR/no_drop_for_inactive_variant.rs:+5:1: +5:2
+    let mut _6: isize;                   // in scope 0 at $DIR/no_drop_for_inactive_variant.rs:+5:1: +5:2
+    let mut _7: isize;                   // in scope 0 at $DIR/no_drop_for_inactive_variant.rs:+5:1: +5:2
     scope 1 {
-        debug x => _3;                   // in scope 1 at $DIR/no-drop-for-inactive-variant.rs:+2:14: +2:15
+        debug x => _3;                   // in scope 1 at $DIR/no_drop_for_inactive_variant.rs:+2:14: +2:15
     }
 
     bb0: {
-        _2 = discriminant(_1);           // scope 0 at $DIR/no-drop-for-inactive-variant.rs:+1:11: +1:14
-        switchInt(move _2) -> [0_isize: bb1, 1_isize: bb3, otherwise: bb2]; // scope 0 at $DIR/no-drop-for-inactive-variant.rs:+1:5: +1:14
+        _2 = discriminant(_1);           // scope 0 at $DIR/no_drop_for_inactive_variant.rs:+1:11: +1:14
+        switchInt(move _2) -> [0_isize: bb1, 1_isize: bb3, otherwise: bb2]; // scope 0 at $DIR/no_drop_for_inactive_variant.rs:+1:5: +1:14
     }
 
     bb1: {
@@ -30,20 +30,20 @@ fn unwrap(_1: Option<T>) -> T {
     }
 
     bb2: {
-        unreachable;                     // scope 0 at $DIR/no-drop-for-inactive-variant.rs:+1:11: +1:14
+        unreachable;                     // scope 0 at $DIR/no_drop_for_inactive_variant.rs:+1:11: +1:14
     }
 
     bb3: {
-        StorageLive(_3);                 // scope 0 at $DIR/no-drop-for-inactive-variant.rs:+2:14: +2:15
-        _3 = move ((_1 as Some).0: T);   // scope 0 at $DIR/no-drop-for-inactive-variant.rs:+2:14: +2:15
-        _0 = move _3;                    // scope 1 at $DIR/no-drop-for-inactive-variant.rs:+2:20: +2:21
-        StorageDead(_3);                 // scope 0 at $DIR/no-drop-for-inactive-variant.rs:+2:20: +2:21
-        _5 = discriminant(_1);           // scope 0 at $DIR/no-drop-for-inactive-variant.rs:+5:1: +5:2
-        return;                          // scope 0 at $DIR/no-drop-for-inactive-variant.rs:+5:2: +5:2
+        StorageLive(_3);                 // scope 0 at $DIR/no_drop_for_inactive_variant.rs:+2:14: +2:15
+        _3 = move ((_1 as Some).0: T);   // scope 0 at $DIR/no_drop_for_inactive_variant.rs:+2:14: +2:15
+        _0 = move _3;                    // scope 1 at $DIR/no_drop_for_inactive_variant.rs:+2:20: +2:21
+        StorageDead(_3);                 // scope 0 at $DIR/no_drop_for_inactive_variant.rs:+2:20: +2:21
+        _5 = discriminant(_1);           // scope 0 at $DIR/no_drop_for_inactive_variant.rs:+5:1: +5:2
+        return;                          // scope 0 at $DIR/no_drop_for_inactive_variant.rs:+5:2: +5:2
     }
 
     bb4 (cleanup): {
-        _7 = discriminant(_1);           // scope 0 at $DIR/no-drop-for-inactive-variant.rs:+5:1: +5:2
-        resume;                          // scope 0 at $DIR/no-drop-for-inactive-variant.rs:+0:1: +5:2
+        _7 = discriminant(_1);           // scope 0 at $DIR/no_drop_for_inactive_variant.rs:+5:1: +5:2
+        resume;                          // scope 0 at $DIR/no_drop_for_inactive_variant.rs:+0:1: +5:2
     }
 }
diff --git a/src/test/mir-opt/no_spurious_drop_after_call.main.ElaborateDrops.before.mir b/src/test/mir-opt/no_spurious_drop_after_call.main.ElaborateDrops.before.mir
index 963e7cde6567..0cb34a2f2747 100644
--- a/src/test/mir-opt/no_spurious_drop_after_call.main.ElaborateDrops.before.mir
+++ b/src/test/mir-opt/no_spurious_drop_after_call.main.ElaborateDrops.before.mir
@@ -1,49 +1,49 @@
 // MIR for `main` before ElaborateDrops
 
 fn main() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/no-spurious-drop-after-call.rs:+0:11: +0:11
-    let _1: ();                          // in scope 0 at $DIR/no-spurious-drop-after-call.rs:+1:5: +1:35
-    let mut _2: std::string::String;     // in scope 0 at $DIR/no-spurious-drop-after-call.rs:+1:20: +1:34
-    let mut _3: &str;                    // in scope 0 at $DIR/no-spurious-drop-after-call.rs:+1:20: +1:34
-    let _4: &str;                        // in scope 0 at $DIR/no-spurious-drop-after-call.rs:+1:20: +1:22
+    let mut _0: ();                      // return place in scope 0 at $DIR/no_spurious_drop_after_call.rs:+0:11: +0:11
+    let _1: ();                          // in scope 0 at $DIR/no_spurious_drop_after_call.rs:+1:5: +1:35
+    let mut _2: std::string::String;     // in scope 0 at $DIR/no_spurious_drop_after_call.rs:+1:20: +1:34
+    let mut _3: &str;                    // in scope 0 at $DIR/no_spurious_drop_after_call.rs:+1:20: +1:34
+    let _4: &str;                        // in scope 0 at $DIR/no_spurious_drop_after_call.rs:+1:20: +1:22
 
     bb0: {
-        StorageLive(_1);                 // scope 0 at $DIR/no-spurious-drop-after-call.rs:+1:5: +1:35
-        StorageLive(_2);                 // scope 0 at $DIR/no-spurious-drop-after-call.rs:+1:20: +1:34
-        StorageLive(_3);                 // scope 0 at $DIR/no-spurious-drop-after-call.rs:+1:20: +1:34
-        StorageLive(_4);                 // scope 0 at $DIR/no-spurious-drop-after-call.rs:+1:20: +1:22
-        _4 = const "";                   // scope 0 at $DIR/no-spurious-drop-after-call.rs:+1:20: +1:22
+        StorageLive(_1);                 // scope 0 at $DIR/no_spurious_drop_after_call.rs:+1:5: +1:35
+        StorageLive(_2);                 // scope 0 at $DIR/no_spurious_drop_after_call.rs:+1:20: +1:34
+        StorageLive(_3);                 // scope 0 at $DIR/no_spurious_drop_after_call.rs:+1:20: +1:34
+        StorageLive(_4);                 // scope 0 at $DIR/no_spurious_drop_after_call.rs:+1:20: +1:22
+        _4 = const "";                   // scope 0 at $DIR/no_spurious_drop_after_call.rs:+1:20: +1:22
                                          // mir::Constant
-                                         // + span: $DIR/no-spurious-drop-after-call.rs:9:20: 9:22
+                                         // + span: $DIR/no_spurious_drop_after_call.rs:9:20: 9:22
                                          // + literal: Const { ty: &str, val: Value(Slice(..)) }
-        _3 = &(*_4);                     // scope 0 at $DIR/no-spurious-drop-after-call.rs:+1:20: +1:34
-        _2 = <str as ToString>::to_string(move _3) -> bb1; // scope 0 at $DIR/no-spurious-drop-after-call.rs:+1:20: +1:34
+        _3 = &(*_4);                     // scope 0 at $DIR/no_spurious_drop_after_call.rs:+1:20: +1:34
+        _2 = <str as ToString>::to_string(move _3) -> bb1; // scope 0 at $DIR/no_spurious_drop_after_call.rs:+1:20: +1:34
                                          // mir::Constant
-                                         // + span: $DIR/no-spurious-drop-after-call.rs:9:23: 9:32
+                                         // + span: $DIR/no_spurious_drop_after_call.rs:9:23: 9:32
                                          // + literal: Const { ty: for<'a> fn(&'a str) -> String {<str as ToString>::to_string}, val: Value(<ZST>) }
     }
 
     bb1: {
-        StorageDead(_3);                 // scope 0 at $DIR/no-spurious-drop-after-call.rs:+1:33: +1:34
-        _1 = std::mem::drop::<String>(move _2) -> [return: bb2, unwind: bb3]; // scope 0 at $DIR/no-spurious-drop-after-call.rs:+1:5: +1:35
+        StorageDead(_3);                 // scope 0 at $DIR/no_spurious_drop_after_call.rs:+1:33: +1:34
+        _1 = std::mem::drop::<String>(move _2) -> [return: bb2, unwind: bb3]; // scope 0 at $DIR/no_spurious_drop_after_call.rs:+1:5: +1:35
                                          // mir::Constant
-                                         // + span: $DIR/no-spurious-drop-after-call.rs:9:5: 9:19
+                                         // + span: $DIR/no_spurious_drop_after_call.rs:9:5: 9:19
                                          // + literal: Const { ty: fn(String) {std::mem::drop::<String>}, val: Value(<ZST>) }
     }
 
     bb2: {
-        StorageDead(_2);                 // scope 0 at $DIR/no-spurious-drop-after-call.rs:+1:34: +1:35
-        StorageDead(_4);                 // scope 0 at $DIR/no-spurious-drop-after-call.rs:+1:35: +1:36
-        StorageDead(_1);                 // scope 0 at $DIR/no-spurious-drop-after-call.rs:+1:35: +1:36
-        _0 = const ();                   // scope 0 at $DIR/no-spurious-drop-after-call.rs:+0:11: +2:2
-        return;                          // scope 0 at $DIR/no-spurious-drop-after-call.rs:+2:2: +2:2
+        StorageDead(_2);                 // scope 0 at $DIR/no_spurious_drop_after_call.rs:+1:34: +1:35
+        StorageDead(_4);                 // scope 0 at $DIR/no_spurious_drop_after_call.rs:+1:35: +1:36
+        StorageDead(_1);                 // scope 0 at $DIR/no_spurious_drop_after_call.rs:+1:35: +1:36
+        _0 = const ();                   // scope 0 at $DIR/no_spurious_drop_after_call.rs:+0:11: +2:2
+        return;                          // scope 0 at $DIR/no_spurious_drop_after_call.rs:+2:2: +2:2
     }
 
     bb3 (cleanup): {
-        drop(_2) -> bb4;                 // scope 0 at $DIR/no-spurious-drop-after-call.rs:+1:34: +1:35
+        drop(_2) -> bb4;                 // scope 0 at $DIR/no_spurious_drop_after_call.rs:+1:34: +1:35
     }
 
     bb4 (cleanup): {
-        resume;                          // scope 0 at $DIR/no-spurious-drop-after-call.rs:+0:1: +2:2
+        resume;                          // scope 0 at $DIR/no_spurious_drop_after_call.rs:+0:1: +2:2
     }
 }
diff --git a/src/test/mir-opt/no-spurious-drop-after-call.rs b/src/test/mir-opt/no_spurious_drop_after_call.rs
similarity index 100%
rename from src/test/mir-opt/no-spurious-drop-after-call.rs
rename to src/test/mir-opt/no_spurious_drop_after_call.rs
diff --git a/src/test/mir-opt/nrvo_simple.nrvo.RenameReturnPlace.diff b/src/test/mir-opt/nrvo_simple.nrvo.RenameReturnPlace.diff
index ce35f920bf62..61a16065bfbd 100644
--- a/src/test/mir-opt/nrvo_simple.nrvo.RenameReturnPlace.diff
+++ b/src/test/mir-opt/nrvo_simple.nrvo.RenameReturnPlace.diff
@@ -2,42 +2,42 @@
 + // MIR for `nrvo` after RenameReturnPlace
   
   fn nrvo(_1: for<'a> fn(&'a mut [u8; 1024])) -> [u8; 1024] {
-      debug init => _1;                    // in scope 0 at $DIR/nrvo-simple.rs:+0:9: +0:13
--     let mut _0: [u8; 1024];              // return place in scope 0 at $DIR/nrvo-simple.rs:+0:39: +0:49
-+     let mut _0: [u8; 1024];              // return place in scope 0 at $DIR/nrvo-simple.rs:+1:9: +1:16
-      let mut _2: [u8; 1024];              // in scope 0 at $DIR/nrvo-simple.rs:+1:9: +1:16
-      let _3: ();                          // in scope 0 at $DIR/nrvo-simple.rs:+2:5: +2:19
-      let mut _4: for<'a> fn(&'a mut [u8; 1024]); // in scope 0 at $DIR/nrvo-simple.rs:+2:5: +2:9
-      let mut _5: &mut [u8; 1024];         // in scope 0 at $DIR/nrvo-simple.rs:+2:10: +2:18
-      let mut _6: &mut [u8; 1024];         // in scope 0 at $DIR/nrvo-simple.rs:+2:10: +2:18
+      debug init => _1;                    // in scope 0 at $DIR/nrvo_simple.rs:+0:9: +0:13
+-     let mut _0: [u8; 1024];              // return place in scope 0 at $DIR/nrvo_simple.rs:+0:39: +0:49
++     let mut _0: [u8; 1024];              // return place in scope 0 at $DIR/nrvo_simple.rs:+1:9: +1:16
+      let mut _2: [u8; 1024];              // in scope 0 at $DIR/nrvo_simple.rs:+1:9: +1:16
+      let _3: ();                          // in scope 0 at $DIR/nrvo_simple.rs:+2:5: +2:19
+      let mut _4: for<'a> fn(&'a mut [u8; 1024]); // in scope 0 at $DIR/nrvo_simple.rs:+2:5: +2:9
+      let mut _5: &mut [u8; 1024];         // in scope 0 at $DIR/nrvo_simple.rs:+2:10: +2:18
+      let mut _6: &mut [u8; 1024];         // in scope 0 at $DIR/nrvo_simple.rs:+2:10: +2:18
       scope 1 {
--         debug buf => _2;                 // in scope 1 at $DIR/nrvo-simple.rs:+1:9: +1:16
-+         debug buf => _0;                 // in scope 1 at $DIR/nrvo-simple.rs:+1:9: +1:16
+-         debug buf => _2;                 // in scope 1 at $DIR/nrvo_simple.rs:+1:9: +1:16
++         debug buf => _0;                 // in scope 1 at $DIR/nrvo_simple.rs:+1:9: +1:16
       }
   
       bb0: {
--         StorageLive(_2);                 // scope 0 at $DIR/nrvo-simple.rs:+1:9: +1:16
--         _2 = [const 0_u8; 1024];         // scope 0 at $DIR/nrvo-simple.rs:+1:19: +1:28
-+         _0 = [const 0_u8; 1024];         // scope 0 at $DIR/nrvo-simple.rs:+1:19: +1:28
-          StorageLive(_3);                 // scope 1 at $DIR/nrvo-simple.rs:+2:5: +2:19
-          StorageLive(_4);                 // scope 1 at $DIR/nrvo-simple.rs:+2:5: +2:9
-          _4 = _1;                         // scope 1 at $DIR/nrvo-simple.rs:+2:5: +2:9
-          StorageLive(_5);                 // scope 1 at $DIR/nrvo-simple.rs:+2:10: +2:18
-          StorageLive(_6);                 // scope 1 at $DIR/nrvo-simple.rs:+2:10: +2:18
--         _6 = &mut _2;                    // scope 1 at $DIR/nrvo-simple.rs:+2:10: +2:18
-+         _6 = &mut _0;                    // scope 1 at $DIR/nrvo-simple.rs:+2:10: +2:18
-          _5 = &mut (*_6);                 // scope 1 at $DIR/nrvo-simple.rs:+2:10: +2:18
-          _3 = move _4(move _5) -> bb1;    // scope 1 at $DIR/nrvo-simple.rs:+2:5: +2:19
+-         StorageLive(_2);                 // scope 0 at $DIR/nrvo_simple.rs:+1:9: +1:16
+-         _2 = [const 0_u8; 1024];         // scope 0 at $DIR/nrvo_simple.rs:+1:19: +1:28
++         _0 = [const 0_u8; 1024];         // scope 0 at $DIR/nrvo_simple.rs:+1:19: +1:28
+          StorageLive(_3);                 // scope 1 at $DIR/nrvo_simple.rs:+2:5: +2:19
+          StorageLive(_4);                 // scope 1 at $DIR/nrvo_simple.rs:+2:5: +2:9
+          _4 = _1;                         // scope 1 at $DIR/nrvo_simple.rs:+2:5: +2:9
+          StorageLive(_5);                 // scope 1 at $DIR/nrvo_simple.rs:+2:10: +2:18
+          StorageLive(_6);                 // scope 1 at $DIR/nrvo_simple.rs:+2:10: +2:18
+-         _6 = &mut _2;                    // scope 1 at $DIR/nrvo_simple.rs:+2:10: +2:18
++         _6 = &mut _0;                    // scope 1 at $DIR/nrvo_simple.rs:+2:10: +2:18
+          _5 = &mut (*_6);                 // scope 1 at $DIR/nrvo_simple.rs:+2:10: +2:18
+          _3 = move _4(move _5) -> bb1;    // scope 1 at $DIR/nrvo_simple.rs:+2:5: +2:19
       }
   
       bb1: {
-          StorageDead(_5);                 // scope 1 at $DIR/nrvo-simple.rs:+2:18: +2:19
-          StorageDead(_4);                 // scope 1 at $DIR/nrvo-simple.rs:+2:18: +2:19
-          StorageDead(_6);                 // scope 1 at $DIR/nrvo-simple.rs:+2:19: +2:20
-          StorageDead(_3);                 // scope 1 at $DIR/nrvo-simple.rs:+2:19: +2:20
--         _0 = _2;                         // scope 1 at $DIR/nrvo-simple.rs:+3:5: +3:8
--         StorageDead(_2);                 // scope 0 at $DIR/nrvo-simple.rs:+4:1: +4:2
-          return;                          // scope 0 at $DIR/nrvo-simple.rs:+4:2: +4:2
+          StorageDead(_5);                 // scope 1 at $DIR/nrvo_simple.rs:+2:18: +2:19
+          StorageDead(_4);                 // scope 1 at $DIR/nrvo_simple.rs:+2:18: +2:19
+          StorageDead(_6);                 // scope 1 at $DIR/nrvo_simple.rs:+2:19: +2:20
+          StorageDead(_3);                 // scope 1 at $DIR/nrvo_simple.rs:+2:19: +2:20
+-         _0 = _2;                         // scope 1 at $DIR/nrvo_simple.rs:+3:5: +3:8
+-         StorageDead(_2);                 // scope 0 at $DIR/nrvo_simple.rs:+4:1: +4:2
+          return;                          // scope 0 at $DIR/nrvo_simple.rs:+4:2: +4:2
       }
   }
   
diff --git a/src/test/mir-opt/nrvo-simple.rs b/src/test/mir-opt/nrvo_simple.rs
similarity index 100%
rename from src/test/mir-opt/nrvo-simple.rs
rename to src/test/mir-opt/nrvo_simple.rs
diff --git a/src/test/mir-opt/packed_struct_drop_aligned.main.SimplifyCfg-elaborate-drops.after.mir b/src/test/mir-opt/packed_struct_drop_aligned.main.SimplifyCfg-elaborate-drops.after.mir
index f9ed1036f006..e522534867d5 100644
--- a/src/test/mir-opt/packed_struct_drop_aligned.main.SimplifyCfg-elaborate-drops.after.mir
+++ b/src/test/mir-opt/packed_struct_drop_aligned.main.SimplifyCfg-elaborate-drops.after.mir
@@ -1,60 +1,60 @@
 // MIR for `main` after SimplifyCfg-elaborate-drops
 
 fn main() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/packed-struct-drop-aligned.rs:+0:11: +0:11
-    let mut _1: Packed;                  // in scope 0 at $DIR/packed-struct-drop-aligned.rs:+1:9: +1:14
-    let mut _2: Aligned;                 // in scope 0 at $DIR/packed-struct-drop-aligned.rs:+1:24: +1:42
-    let mut _3: Droppy;                  // in scope 0 at $DIR/packed-struct-drop-aligned.rs:+1:32: +1:41
-    let mut _4: Aligned;                 // in scope 0 at $DIR/packed-struct-drop-aligned.rs:+2:11: +2:29
-    let mut _5: Droppy;                  // in scope 0 at $DIR/packed-struct-drop-aligned.rs:+2:19: +2:28
-    let mut _6: Aligned;                 // in scope 0 at $DIR/packed-struct-drop-aligned.rs:+2:5: +2:8
+    let mut _0: ();                      // return place in scope 0 at $DIR/packed_struct_drop_aligned.rs:+0:11: +0:11
+    let mut _1: Packed;                  // in scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:9: +1:14
+    let mut _2: Aligned;                 // in scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:24: +1:42
+    let mut _3: Droppy;                  // in scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:32: +1:41
+    let mut _4: Aligned;                 // in scope 0 at $DIR/packed_struct_drop_aligned.rs:+2:11: +2:29
+    let mut _5: Droppy;                  // in scope 0 at $DIR/packed_struct_drop_aligned.rs:+2:19: +2:28
+    let mut _6: Aligned;                 // in scope 0 at $DIR/packed_struct_drop_aligned.rs:+2:5: +2:8
     scope 1 {
-        debug x => _1;                   // in scope 1 at $DIR/packed-struct-drop-aligned.rs:+1:9: +1:14
+        debug x => _1;                   // in scope 1 at $DIR/packed_struct_drop_aligned.rs:+1:9: +1:14
     }
 
     bb0: {
-        StorageLive(_1);                 // scope 0 at $DIR/packed-struct-drop-aligned.rs:+1:9: +1:14
-        StorageLive(_2);                 // scope 0 at $DIR/packed-struct-drop-aligned.rs:+1:24: +1:42
-        StorageLive(_3);                 // scope 0 at $DIR/packed-struct-drop-aligned.rs:+1:32: +1:41
-        Deinit(_3);                      // scope 0 at $DIR/packed-struct-drop-aligned.rs:+1:32: +1:41
-        (_3.0: usize) = const 0_usize;   // scope 0 at $DIR/packed-struct-drop-aligned.rs:+1:32: +1:41
-        Deinit(_2);                      // scope 0 at $DIR/packed-struct-drop-aligned.rs:+1:24: +1:42
-        (_2.0: Droppy) = move _3;        // scope 0 at $DIR/packed-struct-drop-aligned.rs:+1:24: +1:42
-        StorageDead(_3);                 // scope 0 at $DIR/packed-struct-drop-aligned.rs:+1:41: +1:42
-        Deinit(_1);                      // scope 0 at $DIR/packed-struct-drop-aligned.rs:+1:17: +1:43
-        (_1.0: Aligned) = move _2;       // scope 0 at $DIR/packed-struct-drop-aligned.rs:+1:17: +1:43
-        StorageDead(_2);                 // scope 0 at $DIR/packed-struct-drop-aligned.rs:+1:42: +1:43
-        StorageLive(_4);                 // scope 1 at $DIR/packed-struct-drop-aligned.rs:+2:11: +2:29
-        StorageLive(_5);                 // scope 1 at $DIR/packed-struct-drop-aligned.rs:+2:19: +2:28
-        Deinit(_5);                      // scope 1 at $DIR/packed-struct-drop-aligned.rs:+2:19: +2:28
-        (_5.0: usize) = const 0_usize;   // scope 1 at $DIR/packed-struct-drop-aligned.rs:+2:19: +2:28
-        Deinit(_4);                      // scope 1 at $DIR/packed-struct-drop-aligned.rs:+2:11: +2:29
-        (_4.0: Droppy) = move _5;        // scope 1 at $DIR/packed-struct-drop-aligned.rs:+2:11: +2:29
-        StorageDead(_5);                 // scope 1 at $DIR/packed-struct-drop-aligned.rs:+2:28: +2:29
-        StorageLive(_6);                 // scope 1 at $DIR/packed-struct-drop-aligned.rs:+2:5: +2:8
-        _6 = move (_1.0: Aligned);       // scope 1 at $DIR/packed-struct-drop-aligned.rs:+2:5: +2:8
-        drop(_6) -> [return: bb4, unwind: bb3]; // scope 1 at $DIR/packed-struct-drop-aligned.rs:+2:5: +2:8
+        StorageLive(_1);                 // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:9: +1:14
+        StorageLive(_2);                 // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:24: +1:42
+        StorageLive(_3);                 // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:32: +1:41
+        Deinit(_3);                      // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:32: +1:41
+        (_3.0: usize) = const 0_usize;   // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:32: +1:41
+        Deinit(_2);                      // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:24: +1:42
+        (_2.0: Droppy) = move _3;        // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:24: +1:42
+        StorageDead(_3);                 // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:41: +1:42
+        Deinit(_1);                      // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:17: +1:43
+        (_1.0: Aligned) = move _2;       // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:17: +1:43
+        StorageDead(_2);                 // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:42: +1:43
+        StorageLive(_4);                 // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:11: +2:29
+        StorageLive(_5);                 // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:19: +2:28
+        Deinit(_5);                      // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:19: +2:28
+        (_5.0: usize) = const 0_usize;   // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:19: +2:28
+        Deinit(_4);                      // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:11: +2:29
+        (_4.0: Droppy) = move _5;        // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:11: +2:29
+        StorageDead(_5);                 // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:28: +2:29
+        StorageLive(_6);                 // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:5: +2:8
+        _6 = move (_1.0: Aligned);       // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:5: +2:8
+        drop(_6) -> [return: bb4, unwind: bb3]; // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:5: +2:8
     }
 
     bb1: {
-        StorageDead(_1);                 // scope 0 at $DIR/packed-struct-drop-aligned.rs:+3:1: +3:2
-        return;                          // scope 0 at $DIR/packed-struct-drop-aligned.rs:+3:2: +3:2
+        StorageDead(_1);                 // scope 0 at $DIR/packed_struct_drop_aligned.rs:+3:1: +3:2
+        return;                          // scope 0 at $DIR/packed_struct_drop_aligned.rs:+3:2: +3:2
     }
 
     bb2 (cleanup): {
-        resume;                          // scope 0 at $DIR/packed-struct-drop-aligned.rs:+0:1: +3:2
+        resume;                          // scope 0 at $DIR/packed_struct_drop_aligned.rs:+0:1: +3:2
     }
 
     bb3 (cleanup): {
-        (_1.0: Aligned) = move _4;       // scope 1 at $DIR/packed-struct-drop-aligned.rs:+2:5: +2:8
-        drop(_1) -> bb2;                 // scope 0 at $DIR/packed-struct-drop-aligned.rs:+3:1: +3:2
+        (_1.0: Aligned) = move _4;       // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:5: +2:8
+        drop(_1) -> bb2;                 // scope 0 at $DIR/packed_struct_drop_aligned.rs:+3:1: +3:2
     }
 
     bb4: {
-        StorageDead(_6);                 // scope 1 at $DIR/packed-struct-drop-aligned.rs:+2:5: +2:8
-        (_1.0: Aligned) = move _4;       // scope 1 at $DIR/packed-struct-drop-aligned.rs:+2:5: +2:8
-        StorageDead(_4);                 // scope 1 at $DIR/packed-struct-drop-aligned.rs:+2:28: +2:29
-        _0 = const ();                   // scope 0 at $DIR/packed-struct-drop-aligned.rs:+0:11: +3:2
-        drop(_1) -> [return: bb1, unwind: bb2]; // scope 0 at $DIR/packed-struct-drop-aligned.rs:+3:1: +3:2
+        StorageDead(_6);                 // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:5: +2:8
+        (_1.0: Aligned) = move _4;       // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:5: +2:8
+        StorageDead(_4);                 // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:28: +2:29
+        _0 = const ();                   // scope 0 at $DIR/packed_struct_drop_aligned.rs:+0:11: +3:2
+        drop(_1) -> [return: bb1, unwind: bb2]; // scope 0 at $DIR/packed_struct_drop_aligned.rs:+3:1: +3:2
     }
 }
diff --git a/src/test/mir-opt/packed-struct-drop-aligned.rs b/src/test/mir-opt/packed_struct_drop_aligned.rs
similarity index 100%
rename from src/test/mir-opt/packed-struct-drop-aligned.rs
rename to src/test/mir-opt/packed_struct_drop_aligned.rs
diff --git a/src/test/mir-opt/remove_never_const.no_codegen.PreCodegen.after.mir b/src/test/mir-opt/remove_never_const.no_codegen.PreCodegen.after.mir
index 76bdd23be168..8eb0e9c8f483 100644
--- a/src/test/mir-opt/remove_never_const.no_codegen.PreCodegen.after.mir
+++ b/src/test/mir-opt/remove_never_const.no_codegen.PreCodegen.after.mir
@@ -1,11 +1,11 @@
 // MIR for `no_codegen` after PreCodegen
 
 fn no_codegen() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/remove-never-const.rs:+0:20: +0:20
+    let mut _0: ();                      // return place in scope 0 at $DIR/remove_never_const.rs:+0:20: +0:20
     scope 1 {
     }
 
     bb0: {
-        unreachable;                     // scope 0 at $DIR/remove-never-const.rs:+1:13: +1:33
+        unreachable;                     // scope 0 at $DIR/remove_never_const.rs:+1:13: +1:33
     }
 }
diff --git a/src/test/mir-opt/remove-never-const.rs b/src/test/mir-opt/remove_never_const.rs
similarity index 100%
rename from src/test/mir-opt/remove-never-const.rs
rename to src/test/mir-opt/remove_never_const.rs
diff --git a/src/test/mir-opt/rustc.try_identity.DestinationPropagation.diff b/src/test/mir-opt/rustc.try_identity.DestinationPropagation.diff
deleted file mode 100644
index c3e503bf2c68..000000000000
--- a/src/test/mir-opt/rustc.try_identity.DestinationPropagation.diff
+++ /dev/null
@@ -1,72 +0,0 @@
-- // MIR for `try_identity` before DestinationPropagation
-+ // MIR for `try_identity` after DestinationPropagation
-  
-  fn try_identity(_1: std::result::Result<u32, i32>) -> std::result::Result<u32, i32> {
-      debug x => _1;                       // in scope 0 at $DIR/simplify_try.rs:6:17: 6:18
-      let mut _0: std::result::Result<u32, i32>; // return place in scope 0 at $DIR/simplify_try.rs:6:41: 6:57
-      let _2: u32;                         // in scope 0 at $DIR/simplify_try.rs:7:9: 7:10
-      let mut _3: std::result::Result<u32, i32>; // in scope 0 at $DIR/simplify_try.rs:7:13: 7:15
-      let mut _4: std::result::Result<u32, i32>; // in scope 0 at $DIR/simplify_try.rs:7:13: 7:14
-      let mut _5: isize;                   // in scope 0 at $DIR/simplify_try.rs:7:14: 7:15
-      let _6: i32;                         // in scope 0 at $DIR/simplify_try.rs:7:14: 7:15
-      let mut _7: !;                       // in scope 0 at $DIR/simplify_try.rs:7:14: 7:15
-      let mut _8: i32;                     // in scope 0 at $DIR/simplify_try.rs:7:14: 7:15
-      let mut _9: i32;                     // in scope 0 at $DIR/simplify_try.rs:7:14: 7:15
-      let _10: u32;                        // in scope 0 at $DIR/simplify_try.rs:7:13: 7:15
-      let mut _11: u32;                    // in scope 0 at $DIR/simplify_try.rs:8:8: 8:9
-      scope 1 {
-          debug y => _2;                   // in scope 1 at $DIR/simplify_try.rs:7:9: 7:10
-      }
-      scope 2 {
-          debug err => _6;                 // in scope 2 at $DIR/simplify_try.rs:7:14: 7:15
-          scope 3 {
-              scope 7 {
-                  debug t => _9;           // in scope 7 at $SRC_DIR/libcore/convert/mod.rs:LL:COL
-              }
-              scope 8 {
-                  debug v => _8;           // in scope 8 at $SRC_DIR/libcore/result.rs:LL:COL
-                  let mut _12: i32;        // in scope 8 at $DIR/simplify_try.rs:7:14: 7:15
-              }
-          }
-      }
-      scope 4 {
-          debug val => _10;                // in scope 4 at $DIR/simplify_try.rs:7:13: 7:15
-          scope 5 {
-          }
-      }
-      scope 6 {
--         debug self => _4;                // in scope 6 at $SRC_DIR/libcore/result.rs:LL:COL
-+         debug self => _0;                // in scope 6 at $SRC_DIR/libcore/result.rs:LL:COL
-      }
-  
-      bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/simplify_try.rs:7:9: 7:10
--         StorageLive(_3);                 // scope 0 at $DIR/simplify_try.rs:7:13: 7:15
--         StorageLive(_4);                 // scope 0 at $DIR/simplify_try.rs:7:13: 7:14
--         _4 = _1;                         // scope 0 at $DIR/simplify_try.rs:7:13: 7:14
--         _3 = move _4;                    // scope 6 at $SRC_DIR/libcore/result.rs:LL:COL
--         StorageDead(_4);                 // scope 0 at $DIR/simplify_try.rs:7:14: 7:15
--         _5 = discriminant(_3);           // scope 0 at $DIR/simplify_try.rs:7:14: 7:15
-+         nop;                             // scope 0 at $DIR/simplify_try.rs:7:13: 7:15
-+         nop;                             // scope 0 at $DIR/simplify_try.rs:7:13: 7:14
-+         _0 = _1;                         // scope 0 at $DIR/simplify_try.rs:7:13: 7:14
-+         nop;                             // scope 6 at $SRC_DIR/libcore/result.rs:LL:COL
-+         nop;                             // scope 0 at $DIR/simplify_try.rs:7:14: 7:15
-+         _5 = discriminant(_0);           // scope 0 at $DIR/simplify_try.rs:7:14: 7:15
-          goto -> bb1;                     // scope 0 at $DIR/simplify_try.rs:7:14: 7:15
-      }
-  
-      bb1: {
--         _0 = move _3;                    // scope 1 at $DIR/simplify_try.rs:8:5: 8:10
--         StorageDead(_3);                 // scope 0 at $DIR/simplify_try.rs:7:15: 7:16
-+         nop;                             // scope 1 at $DIR/simplify_try.rs:8:5: 8:10
-+         nop;                             // scope 0 at $DIR/simplify_try.rs:7:15: 7:16
-          StorageDead(_2);                 // scope 0 at $DIR/simplify_try.rs:9:1: 9:2
-          goto -> bb2;                     // scope 0 at $DIR/simplify_try.rs:9:2: 9:2
-      }
-  
-      bb2: {
-          return;                          // scope 0 at $DIR/simplify_try.rs:9:2: 9:2
-      }
-  }
-  
diff --git a/src/test/mir-opt/simplify-arm.rs b/src/test/mir-opt/simplify_arm.rs
similarity index 100%
rename from src/test/mir-opt/simplify-arm.rs
rename to src/test/mir-opt/simplify_arm.rs
diff --git a/src/test/mir-opt/simplify-arm-identity.rs b/src/test/mir-opt/simplify_arm_identity.rs
similarity index 100%
rename from src/test/mir-opt/simplify-arm-identity.rs
rename to src/test/mir-opt/simplify_arm_identity.rs
diff --git a/src/test/mir-opt/simplify_locals.c.SimplifyLocals.diff b/src/test/mir-opt/simplify_locals.c.SimplifyLocals.diff
index 5d7517e4eb43..1a5143aa0fa0 100644
--- a/src/test/mir-opt/simplify_locals.c.SimplifyLocals.diff
+++ b/src/test/mir-opt/simplify_locals.c.SimplifyLocals.diff
@@ -2,32 +2,32 @@
 + // MIR for `c` after SimplifyLocals
   
   fn c() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/simplify-locals.rs:+0:8: +0:8
-      let _1: [u8; 10];                    // in scope 0 at $DIR/simplify-locals.rs:+1:9: +1:14
--     let mut _2: &[u8];                   // in scope 0 at $DIR/simplify-locals.rs:+3:20: +3:26
--     let mut _3: &[u8; 10];               // in scope 0 at $DIR/simplify-locals.rs:+3:20: +3:26
--     let _4: &[u8; 10];                   // in scope 0 at $DIR/simplify-locals.rs:+3:20: +3:26
+      let mut _0: ();                      // return place in scope 0 at $DIR/simplify_locals.rs:+0:8: +0:8
+      let _1: [u8; 10];                    // in scope 0 at $DIR/simplify_locals.rs:+1:9: +1:14
+-     let mut _2: &[u8];                   // in scope 0 at $DIR/simplify_locals.rs:+3:20: +3:26
+-     let mut _3: &[u8; 10];               // in scope 0 at $DIR/simplify_locals.rs:+3:20: +3:26
+-     let _4: &[u8; 10];                   // in scope 0 at $DIR/simplify_locals.rs:+3:20: +3:26
       scope 1 {
-          debug bytes => _1;               // in scope 1 at $DIR/simplify-locals.rs:+1:9: +1:14
+          debug bytes => _1;               // in scope 1 at $DIR/simplify_locals.rs:+1:9: +1:14
           scope 2 {
           }
       }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/simplify-locals.rs:+1:9: +1:14
-          _1 = [const 0_u8; 10];           // scope 0 at $DIR/simplify-locals.rs:+1:17: +1:26
--         StorageLive(_2);                 // scope 1 at $DIR/simplify-locals.rs:+3:20: +3:26
--         StorageLive(_3);                 // scope 1 at $DIR/simplify-locals.rs:+3:20: +3:26
--         StorageLive(_4);                 // scope 1 at $DIR/simplify-locals.rs:+3:20: +3:26
--         _4 = &_1;                        // scope 1 at $DIR/simplify-locals.rs:+3:20: +3:26
--         _3 = &(*_4);                     // scope 1 at $DIR/simplify-locals.rs:+3:20: +3:26
--         _2 = move _3 as &[u8] (Pointer(Unsize)); // scope 1 at $DIR/simplify-locals.rs:+3:20: +3:26
--         StorageDead(_3);                 // scope 1 at $DIR/simplify-locals.rs:+3:25: +3:26
--         StorageDead(_4);                 // scope 1 at $DIR/simplify-locals.rs:+3:26: +3:27
--         StorageDead(_2);                 // scope 1 at $DIR/simplify-locals.rs:+3:26: +3:27
-          _0 = const ();                   // scope 0 at $DIR/simplify-locals.rs:+0:8: +4:2
-          StorageDead(_1);                 // scope 0 at $DIR/simplify-locals.rs:+4:1: +4:2
-          return;                          // scope 0 at $DIR/simplify-locals.rs:+4:2: +4:2
+          StorageLive(_1);                 // scope 0 at $DIR/simplify_locals.rs:+1:9: +1:14
+          _1 = [const 0_u8; 10];           // scope 0 at $DIR/simplify_locals.rs:+1:17: +1:26
+-         StorageLive(_2);                 // scope 1 at $DIR/simplify_locals.rs:+3:20: +3:26
+-         StorageLive(_3);                 // scope 1 at $DIR/simplify_locals.rs:+3:20: +3:26
+-         StorageLive(_4);                 // scope 1 at $DIR/simplify_locals.rs:+3:20: +3:26
+-         _4 = &_1;                        // scope 1 at $DIR/simplify_locals.rs:+3:20: +3:26
+-         _3 = &(*_4);                     // scope 1 at $DIR/simplify_locals.rs:+3:20: +3:26
+-         _2 = move _3 as &[u8] (Pointer(Unsize)); // scope 1 at $DIR/simplify_locals.rs:+3:20: +3:26
+-         StorageDead(_3);                 // scope 1 at $DIR/simplify_locals.rs:+3:25: +3:26
+-         StorageDead(_4);                 // scope 1 at $DIR/simplify_locals.rs:+3:26: +3:27
+-         StorageDead(_2);                 // scope 1 at $DIR/simplify_locals.rs:+3:26: +3:27
+          _0 = const ();                   // scope 0 at $DIR/simplify_locals.rs:+0:8: +4:2
+          StorageDead(_1);                 // scope 0 at $DIR/simplify_locals.rs:+4:1: +4:2
+          return;                          // scope 0 at $DIR/simplify_locals.rs:+4:2: +4:2
       }
   }
   
diff --git a/src/test/mir-opt/simplify_locals.d1.SimplifyLocals.diff b/src/test/mir-opt/simplify_locals.d1.SimplifyLocals.diff
index a9ea8869a969..6426bf926a43 100644
--- a/src/test/mir-opt/simplify_locals.d1.SimplifyLocals.diff
+++ b/src/test/mir-opt/simplify_locals.d1.SimplifyLocals.diff
@@ -2,18 +2,18 @@
 + // MIR for `d1` after SimplifyLocals
   
   fn d1() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/simplify-locals.rs:+0:9: +0:9
--     let mut _1: E;                       // in scope 0 at $DIR/simplify-locals.rs:+2:13: +2:17
+      let mut _0: ();                      // return place in scope 0 at $DIR/simplify_locals.rs:+0:9: +0:9
+-     let mut _1: E;                       // in scope 0 at $DIR/simplify_locals.rs:+2:13: +2:17
       scope 1 {
       }
   
       bb0: {
--         StorageLive(_1);                 // scope 0 at $DIR/simplify-locals.rs:+2:13: +2:17
--         Deinit(_1);                      // scope 0 at $DIR/simplify-locals.rs:+2:13: +2:17
--         discriminant(_1) = 0;            // scope 0 at $DIR/simplify-locals.rs:+2:13: +2:17
--         StorageDead(_1);                 // scope 0 at $DIR/simplify-locals.rs:+2:17: +2:18
-          _0 = const ();                   // scope 0 at $DIR/simplify-locals.rs:+0:9: +3:2
-          return;                          // scope 0 at $DIR/simplify-locals.rs:+3:2: +3:2
+-         StorageLive(_1);                 // scope 0 at $DIR/simplify_locals.rs:+2:13: +2:17
+-         Deinit(_1);                      // scope 0 at $DIR/simplify_locals.rs:+2:13: +2:17
+-         discriminant(_1) = 0;            // scope 0 at $DIR/simplify_locals.rs:+2:13: +2:17
+-         StorageDead(_1);                 // scope 0 at $DIR/simplify_locals.rs:+2:17: +2:18
+          _0 = const ();                   // scope 0 at $DIR/simplify_locals.rs:+0:9: +3:2
+          return;                          // scope 0 at $DIR/simplify_locals.rs:+3:2: +3:2
       }
   }
   
diff --git a/src/test/mir-opt/simplify_locals.d2.SimplifyLocals.diff b/src/test/mir-opt/simplify_locals.d2.SimplifyLocals.diff
index 6a89e45843b9..db5ab182d6f3 100644
--- a/src/test/mir-opt/simplify_locals.d2.SimplifyLocals.diff
+++ b/src/test/mir-opt/simplify_locals.d2.SimplifyLocals.diff
@@ -2,28 +2,28 @@
 + // MIR for `d2` after SimplifyLocals
   
   fn d2() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/simplify-locals.rs:+0:9: +0:9
--     let mut _1: E;                       // in scope 0 at $DIR/simplify-locals.rs:+2:22: +2:26
--     let mut _2: (i32, E);                // in scope 0 at $DIR/simplify-locals.rs:+2:5: +2:17
--     let mut _3: E;                       // in scope 0 at $DIR/simplify-locals.rs:+2:11: +2:15
+      let mut _0: ();                      // return place in scope 0 at $DIR/simplify_locals.rs:+0:9: +0:9
+-     let mut _1: E;                       // in scope 0 at $DIR/simplify_locals.rs:+2:22: +2:26
+-     let mut _2: (i32, E);                // in scope 0 at $DIR/simplify_locals.rs:+2:5: +2:17
+-     let mut _3: E;                       // in scope 0 at $DIR/simplify_locals.rs:+2:11: +2:15
   
       bb0: {
--         StorageLive(_1);                 // scope 0 at $DIR/simplify-locals.rs:+2:22: +2:26
--         Deinit(_1);                      // scope 0 at $DIR/simplify-locals.rs:+2:22: +2:26
--         discriminant(_1) = 1;            // scope 0 at $DIR/simplify-locals.rs:+2:22: +2:26
--         StorageLive(_2);                 // scope 0 at $DIR/simplify-locals.rs:+2:5: +2:17
--         StorageLive(_3);                 // scope 0 at $DIR/simplify-locals.rs:+2:11: +2:15
--         Deinit(_3);                      // scope 0 at $DIR/simplify-locals.rs:+2:11: +2:15
--         discriminant(_3) = 0;            // scope 0 at $DIR/simplify-locals.rs:+2:11: +2:15
--         Deinit(_2);                      // scope 0 at $DIR/simplify-locals.rs:+2:6: +2:16
--         (_2.0: i32) = const 10_i32;      // scope 0 at $DIR/simplify-locals.rs:+2:6: +2:16
--         (_2.1: E) = move _3;             // scope 0 at $DIR/simplify-locals.rs:+2:6: +2:16
--         StorageDead(_3);                 // scope 0 at $DIR/simplify-locals.rs:+2:15: +2:16
--         (_2.1: E) = move _1;             // scope 0 at $DIR/simplify-locals.rs:+2:5: +2:26
--         StorageDead(_1);                 // scope 0 at $DIR/simplify-locals.rs:+2:25: +2:26
--         StorageDead(_2);                 // scope 0 at $DIR/simplify-locals.rs:+2:26: +2:27
-          _0 = const ();                   // scope 0 at $DIR/simplify-locals.rs:+0:9: +3:2
-          return;                          // scope 0 at $DIR/simplify-locals.rs:+3:2: +3:2
+-         StorageLive(_1);                 // scope 0 at $DIR/simplify_locals.rs:+2:22: +2:26
+-         Deinit(_1);                      // scope 0 at $DIR/simplify_locals.rs:+2:22: +2:26
+-         discriminant(_1) = 1;            // scope 0 at $DIR/simplify_locals.rs:+2:22: +2:26
+-         StorageLive(_2);                 // scope 0 at $DIR/simplify_locals.rs:+2:5: +2:17
+-         StorageLive(_3);                 // scope 0 at $DIR/simplify_locals.rs:+2:11: +2:15
+-         Deinit(_3);                      // scope 0 at $DIR/simplify_locals.rs:+2:11: +2:15
+-         discriminant(_3) = 0;            // scope 0 at $DIR/simplify_locals.rs:+2:11: +2:15
+-         Deinit(_2);                      // scope 0 at $DIR/simplify_locals.rs:+2:6: +2:16
+-         (_2.0: i32) = const 10_i32;      // scope 0 at $DIR/simplify_locals.rs:+2:6: +2:16
+-         (_2.1: E) = move _3;             // scope 0 at $DIR/simplify_locals.rs:+2:6: +2:16
+-         StorageDead(_3);                 // scope 0 at $DIR/simplify_locals.rs:+2:15: +2:16
+-         (_2.1: E) = move _1;             // scope 0 at $DIR/simplify_locals.rs:+2:5: +2:26
+-         StorageDead(_1);                 // scope 0 at $DIR/simplify_locals.rs:+2:25: +2:26
+-         StorageDead(_2);                 // scope 0 at $DIR/simplify_locals.rs:+2:26: +2:27
+          _0 = const ();                   // scope 0 at $DIR/simplify_locals.rs:+0:9: +3:2
+          return;                          // scope 0 at $DIR/simplify_locals.rs:+3:2: +3:2
       }
   }
   
diff --git a/src/test/mir-opt/simplify_locals.expose_addr.SimplifyLocals.diff b/src/test/mir-opt/simplify_locals.expose_addr.SimplifyLocals.diff
index 204a1bffc81a..c707b0da07e0 100644
--- a/src/test/mir-opt/simplify_locals.expose_addr.SimplifyLocals.diff
+++ b/src/test/mir-opt/simplify_locals.expose_addr.SimplifyLocals.diff
@@ -2,20 +2,20 @@
 + // MIR for `expose_addr` after SimplifyLocals
   
   fn expose_addr(_1: *const usize) -> () {
-      debug p => _1;                       // in scope 0 at $DIR/simplify-locals.rs:+0:16: +0:17
-      let mut _0: ();                      // return place in scope 0 at $DIR/simplify-locals.rs:+0:33: +0:33
-      let _2: usize;                       // in scope 0 at $DIR/simplify-locals.rs:+2:5: +2:15
-      let mut _3: *const usize;            // in scope 0 at $DIR/simplify-locals.rs:+2:5: +2:6
+      debug p => _1;                       // in scope 0 at $DIR/simplify_locals.rs:+0:16: +0:17
+      let mut _0: ();                      // return place in scope 0 at $DIR/simplify_locals.rs:+0:33: +0:33
+      let _2: usize;                       // in scope 0 at $DIR/simplify_locals.rs:+2:5: +2:15
+      let mut _3: *const usize;            // in scope 0 at $DIR/simplify_locals.rs:+2:5: +2:6
   
       bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/simplify-locals.rs:+2:5: +2:15
-          StorageLive(_3);                 // scope 0 at $DIR/simplify-locals.rs:+2:5: +2:6
-          _3 = _1;                         // scope 0 at $DIR/simplify-locals.rs:+2:5: +2:6
-          _2 = move _3 as usize (PointerExposeAddress); // scope 0 at $DIR/simplify-locals.rs:+2:5: +2:15
-          StorageDead(_3);                 // scope 0 at $DIR/simplify-locals.rs:+2:14: +2:15
-          StorageDead(_2);                 // scope 0 at $DIR/simplify-locals.rs:+2:15: +2:16
-          _0 = const ();                   // scope 0 at $DIR/simplify-locals.rs:+0:33: +3:2
-          return;                          // scope 0 at $DIR/simplify-locals.rs:+3:2: +3:2
+          StorageLive(_2);                 // scope 0 at $DIR/simplify_locals.rs:+2:5: +2:15
+          StorageLive(_3);                 // scope 0 at $DIR/simplify_locals.rs:+2:5: +2:6
+          _3 = _1;                         // scope 0 at $DIR/simplify_locals.rs:+2:5: +2:6
+          _2 = move _3 as usize (PointerExposeAddress); // scope 0 at $DIR/simplify_locals.rs:+2:5: +2:15
+          StorageDead(_3);                 // scope 0 at $DIR/simplify_locals.rs:+2:14: +2:15
+          StorageDead(_2);                 // scope 0 at $DIR/simplify_locals.rs:+2:15: +2:16
+          _0 = const ();                   // scope 0 at $DIR/simplify_locals.rs:+0:33: +3:2
+          return;                          // scope 0 at $DIR/simplify_locals.rs:+3:2: +3:2
       }
   }
   
diff --git a/src/test/mir-opt/simplify_locals.r.SimplifyLocals.diff b/src/test/mir-opt/simplify_locals.r.SimplifyLocals.diff
index 329e2a65a0d0..ff6eb2cff5e9 100644
--- a/src/test/mir-opt/simplify_locals.r.SimplifyLocals.diff
+++ b/src/test/mir-opt/simplify_locals.r.SimplifyLocals.diff
@@ -2,12 +2,12 @@
 + // MIR for `r` after SimplifyLocals
   
   fn r() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/simplify-locals.rs:+0:8: +0:8
-      let mut _1: i32;                     // in scope 0 at $DIR/simplify-locals.rs:+1:9: +1:14
--     let mut _2: &i32;                    // in scope 0 at $DIR/simplify-locals.rs:+3:13: +3:15
--     let mut _3: &mut i32;                // in scope 0 at $DIR/simplify-locals.rs:+4:13: +4:19
+      let mut _0: ();                      // return place in scope 0 at $DIR/simplify_locals.rs:+0:8: +0:8
+      let mut _1: i32;                     // in scope 0 at $DIR/simplify_locals.rs:+1:9: +1:14
+-     let mut _2: &i32;                    // in scope 0 at $DIR/simplify_locals.rs:+3:13: +3:15
+-     let mut _3: &mut i32;                // in scope 0 at $DIR/simplify_locals.rs:+4:13: +4:19
       scope 1 {
-          debug a => _1;                   // in scope 1 at $DIR/simplify-locals.rs:+1:9: +1:14
+          debug a => _1;                   // in scope 1 at $DIR/simplify_locals.rs:+1:9: +1:14
           scope 2 {
               scope 3 {
               }
@@ -15,17 +15,17 @@
       }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/simplify-locals.rs:+1:9: +1:14
-          _1 = const 1_i32;                // scope 0 at $DIR/simplify-locals.rs:+1:17: +1:18
--         StorageLive(_2);                 // scope 1 at $DIR/simplify-locals.rs:+3:13: +3:15
--         _2 = &_1;                        // scope 1 at $DIR/simplify-locals.rs:+3:13: +3:15
--         StorageDead(_2);                 // scope 1 at $DIR/simplify-locals.rs:+3:15: +3:16
--         StorageLive(_3);                 // scope 2 at $DIR/simplify-locals.rs:+4:13: +4:19
--         _3 = &mut _1;                    // scope 2 at $DIR/simplify-locals.rs:+4:13: +4:19
--         StorageDead(_3);                 // scope 2 at $DIR/simplify-locals.rs:+4:19: +4:20
-          _0 = const ();                   // scope 0 at $DIR/simplify-locals.rs:+0:8: +5:2
-          StorageDead(_1);                 // scope 0 at $DIR/simplify-locals.rs:+5:1: +5:2
-          return;                          // scope 0 at $DIR/simplify-locals.rs:+5:2: +5:2
+          StorageLive(_1);                 // scope 0 at $DIR/simplify_locals.rs:+1:9: +1:14
+          _1 = const 1_i32;                // scope 0 at $DIR/simplify_locals.rs:+1:17: +1:18
+-         StorageLive(_2);                 // scope 1 at $DIR/simplify_locals.rs:+3:13: +3:15
+-         _2 = &_1;                        // scope 1 at $DIR/simplify_locals.rs:+3:13: +3:15
+-         StorageDead(_2);                 // scope 1 at $DIR/simplify_locals.rs:+3:15: +3:16
+-         StorageLive(_3);                 // scope 2 at $DIR/simplify_locals.rs:+4:13: +4:19
+-         _3 = &mut _1;                    // scope 2 at $DIR/simplify_locals.rs:+4:13: +4:19
+-         StorageDead(_3);                 // scope 2 at $DIR/simplify_locals.rs:+4:19: +4:20
+          _0 = const ();                   // scope 0 at $DIR/simplify_locals.rs:+0:8: +5:2
+          StorageDead(_1);                 // scope 0 at $DIR/simplify_locals.rs:+5:1: +5:2
+          return;                          // scope 0 at $DIR/simplify_locals.rs:+5:2: +5:2
       }
   }
   
diff --git a/src/test/mir-opt/simplify-locals.rs b/src/test/mir-opt/simplify_locals.rs
similarity index 100%
rename from src/test/mir-opt/simplify-locals.rs
rename to src/test/mir-opt/simplify_locals.rs
diff --git a/src/test/mir-opt/simplify_locals.t1.SimplifyLocals.diff b/src/test/mir-opt/simplify_locals.t1.SimplifyLocals.diff
index b31156ad6977..49db77479638 100644
--- a/src/test/mir-opt/simplify_locals.t1.SimplifyLocals.diff
+++ b/src/test/mir-opt/simplify_locals.t1.SimplifyLocals.diff
@@ -2,21 +2,21 @@
 + // MIR for `t1` after SimplifyLocals
   
   fn t1() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/simplify-locals.rs:+0:9: +0:9
--     let _1: u32;                         // in scope 0 at $DIR/simplify-locals.rs:+2:14: +2:15
--     let mut _2: *mut u32;                // in scope 0 at $DIR/simplify-locals.rs:+2:14: +2:15
+      let mut _0: ();                      // return place in scope 0 at $DIR/simplify_locals.rs:+0:9: +0:9
+-     let _1: u32;                         // in scope 0 at $DIR/simplify_locals.rs:+2:14: +2:15
+-     let mut _2: *mut u32;                // in scope 0 at $DIR/simplify_locals.rs:+2:14: +2:15
       scope 1 {
       }
   
       bb0: {
--         StorageLive(_1);                 // scope 0 at $DIR/simplify-locals.rs:+2:5: +2:17
--         StorageLive(_2);                 // scope 1 at $DIR/simplify-locals.rs:+2:14: +2:15
--         _2 = &/*tls*/ mut X;             // scope 1 at $DIR/simplify-locals.rs:+2:14: +2:15
--         _1 = (*_2);                      // scope 1 at $DIR/simplify-locals.rs:+2:14: +2:15
--         StorageDead(_2);                 // scope 0 at $DIR/simplify-locals.rs:+2:17: +2:18
--         StorageDead(_1);                 // scope 0 at $DIR/simplify-locals.rs:+2:17: +2:18
-          _0 = const ();                   // scope 0 at $DIR/simplify-locals.rs:+0:9: +3:2
-          return;                          // scope 0 at $DIR/simplify-locals.rs:+3:2: +3:2
+-         StorageLive(_1);                 // scope 0 at $DIR/simplify_locals.rs:+2:5: +2:17
+-         StorageLive(_2);                 // scope 1 at $DIR/simplify_locals.rs:+2:14: +2:15
+-         _2 = &/*tls*/ mut X;             // scope 1 at $DIR/simplify_locals.rs:+2:14: +2:15
+-         _1 = (*_2);                      // scope 1 at $DIR/simplify_locals.rs:+2:14: +2:15
+-         StorageDead(_2);                 // scope 0 at $DIR/simplify_locals.rs:+2:17: +2:18
+-         StorageDead(_1);                 // scope 0 at $DIR/simplify_locals.rs:+2:17: +2:18
+          _0 = const ();                   // scope 0 at $DIR/simplify_locals.rs:+0:9: +3:2
+          return;                          // scope 0 at $DIR/simplify_locals.rs:+3:2: +3:2
       }
   }
   
diff --git a/src/test/mir-opt/simplify_locals.t2.SimplifyLocals.diff b/src/test/mir-opt/simplify_locals.t2.SimplifyLocals.diff
index 66b6d8d64864..e3f4ae3701b0 100644
--- a/src/test/mir-opt/simplify_locals.t2.SimplifyLocals.diff
+++ b/src/test/mir-opt/simplify_locals.t2.SimplifyLocals.diff
@@ -2,21 +2,21 @@
 + // MIR for `t2` after SimplifyLocals
   
   fn t2() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/simplify-locals.rs:+0:9: +0:9
--     let _1: &mut u32;                    // in scope 0 at $DIR/simplify-locals.rs:+2:14: +2:20
--     let mut _2: *mut u32;                // in scope 0 at $DIR/simplify-locals.rs:+2:19: +2:20
+      let mut _0: ();                      // return place in scope 0 at $DIR/simplify_locals.rs:+0:9: +0:9
+-     let _1: &mut u32;                    // in scope 0 at $DIR/simplify_locals.rs:+2:14: +2:20
+-     let mut _2: *mut u32;                // in scope 0 at $DIR/simplify_locals.rs:+2:19: +2:20
       scope 1 {
       }
   
       bb0: {
--         StorageLive(_1);                 // scope 0 at $DIR/simplify-locals.rs:+2:5: +2:22
--         StorageLive(_2);                 // scope 1 at $DIR/simplify-locals.rs:+2:19: +2:20
--         _2 = &/*tls*/ mut X;             // scope 1 at $DIR/simplify-locals.rs:+2:19: +2:20
--         _1 = &mut (*_2);                 // scope 1 at $DIR/simplify-locals.rs:+2:14: +2:20
--         StorageDead(_2);                 // scope 0 at $DIR/simplify-locals.rs:+2:22: +2:23
--         StorageDead(_1);                 // scope 0 at $DIR/simplify-locals.rs:+2:22: +2:23
-          _0 = const ();                   // scope 0 at $DIR/simplify-locals.rs:+0:9: +3:2
-          return;                          // scope 0 at $DIR/simplify-locals.rs:+3:2: +3:2
+-         StorageLive(_1);                 // scope 0 at $DIR/simplify_locals.rs:+2:5: +2:22
+-         StorageLive(_2);                 // scope 1 at $DIR/simplify_locals.rs:+2:19: +2:20
+-         _2 = &/*tls*/ mut X;             // scope 1 at $DIR/simplify_locals.rs:+2:19: +2:20
+-         _1 = &mut (*_2);                 // scope 1 at $DIR/simplify_locals.rs:+2:14: +2:20
+-         StorageDead(_2);                 // scope 0 at $DIR/simplify_locals.rs:+2:22: +2:23
+-         StorageDead(_1);                 // scope 0 at $DIR/simplify_locals.rs:+2:22: +2:23
+          _0 = const ();                   // scope 0 at $DIR/simplify_locals.rs:+0:9: +3:2
+          return;                          // scope 0 at $DIR/simplify_locals.rs:+3:2: +3:2
       }
   }
   
diff --git a/src/test/mir-opt/simplify_locals.t3.SimplifyLocals.diff b/src/test/mir-opt/simplify_locals.t3.SimplifyLocals.diff
index f6b6b78cdfbe..f1ce7778e191 100644
--- a/src/test/mir-opt/simplify_locals.t3.SimplifyLocals.diff
+++ b/src/test/mir-opt/simplify_locals.t3.SimplifyLocals.diff
@@ -2,25 +2,25 @@
 + // MIR for `t3` after SimplifyLocals
   
   fn t3() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/simplify-locals.rs:+0:9: +0:9
--     let _1: u32;                         // in scope 0 at $DIR/simplify-locals.rs:+2:14: +2:21
--     let mut _2: &mut u32;                // in scope 0 at $DIR/simplify-locals.rs:+2:15: +2:21
--     let mut _3: *mut u32;                // in scope 0 at $DIR/simplify-locals.rs:+2:20: +2:21
+      let mut _0: ();                      // return place in scope 0 at $DIR/simplify_locals.rs:+0:9: +0:9
+-     let _1: u32;                         // in scope 0 at $DIR/simplify_locals.rs:+2:14: +2:21
+-     let mut _2: &mut u32;                // in scope 0 at $DIR/simplify_locals.rs:+2:15: +2:21
+-     let mut _3: *mut u32;                // in scope 0 at $DIR/simplify_locals.rs:+2:20: +2:21
       scope 1 {
       }
   
       bb0: {
--         StorageLive(_1);                 // scope 0 at $DIR/simplify-locals.rs:+2:5: +2:23
--         StorageLive(_2);                 // scope 1 at $DIR/simplify-locals.rs:+2:15: +2:21
--         StorageLive(_3);                 // scope 1 at $DIR/simplify-locals.rs:+2:20: +2:21
--         _3 = &/*tls*/ mut X;             // scope 1 at $DIR/simplify-locals.rs:+2:20: +2:21
--         _2 = &mut (*_3);                 // scope 1 at $DIR/simplify-locals.rs:+2:15: +2:21
--         _1 = (*_2);                      // scope 1 at $DIR/simplify-locals.rs:+2:14: +2:21
--         StorageDead(_3);                 // scope 0 at $DIR/simplify-locals.rs:+2:23: +2:24
--         StorageDead(_2);                 // scope 0 at $DIR/simplify-locals.rs:+2:23: +2:24
--         StorageDead(_1);                 // scope 0 at $DIR/simplify-locals.rs:+2:23: +2:24
-          _0 = const ();                   // scope 0 at $DIR/simplify-locals.rs:+0:9: +3:2
-          return;                          // scope 0 at $DIR/simplify-locals.rs:+3:2: +3:2
+-         StorageLive(_1);                 // scope 0 at $DIR/simplify_locals.rs:+2:5: +2:23
+-         StorageLive(_2);                 // scope 1 at $DIR/simplify_locals.rs:+2:15: +2:21
+-         StorageLive(_3);                 // scope 1 at $DIR/simplify_locals.rs:+2:20: +2:21
+-         _3 = &/*tls*/ mut X;             // scope 1 at $DIR/simplify_locals.rs:+2:20: +2:21
+-         _2 = &mut (*_3);                 // scope 1 at $DIR/simplify_locals.rs:+2:15: +2:21
+-         _1 = (*_2);                      // scope 1 at $DIR/simplify_locals.rs:+2:14: +2:21
+-         StorageDead(_3);                 // scope 0 at $DIR/simplify_locals.rs:+2:23: +2:24
+-         StorageDead(_2);                 // scope 0 at $DIR/simplify_locals.rs:+2:23: +2:24
+-         StorageDead(_1);                 // scope 0 at $DIR/simplify_locals.rs:+2:23: +2:24
+          _0 = const ();                   // scope 0 at $DIR/simplify_locals.rs:+0:9: +3:2
+          return;                          // scope 0 at $DIR/simplify_locals.rs:+3:2: +3:2
       }
   }
   
diff --git a/src/test/mir-opt/simplify_locals.t4.SimplifyLocals.diff b/src/test/mir-opt/simplify_locals.t4.SimplifyLocals.diff
index 1c1da29aa678..71cf9594b9eb 100644
--- a/src/test/mir-opt/simplify_locals.t4.SimplifyLocals.diff
+++ b/src/test/mir-opt/simplify_locals.t4.SimplifyLocals.diff
@@ -2,21 +2,21 @@
 + // MIR for `t4` after SimplifyLocals
   
   fn t4() -> u32 {
-      let mut _0: u32;                     // return place in scope 0 at $DIR/simplify-locals.rs:+0:12: +0:15
-      let mut _1: u32;                     // in scope 0 at $DIR/simplify-locals.rs:+2:14: +2:15
-      let mut _2: *mut u32;                // in scope 0 at $DIR/simplify-locals.rs:+2:14: +2:15
+      let mut _0: u32;                     // return place in scope 0 at $DIR/simplify_locals.rs:+0:12: +0:15
+      let mut _1: u32;                     // in scope 0 at $DIR/simplify_locals.rs:+2:14: +2:15
+      let mut _2: *mut u32;                // in scope 0 at $DIR/simplify_locals.rs:+2:14: +2:15
       scope 1 {
       }
   
       bb0: {
-          StorageLive(_1);                 // scope 1 at $DIR/simplify-locals.rs:+2:14: +2:15
-          StorageLive(_2);                 // scope 1 at $DIR/simplify-locals.rs:+2:14: +2:15
-          _2 = &/*tls*/ mut X;             // scope 1 at $DIR/simplify-locals.rs:+2:14: +2:15
-          _1 = (*_2);                      // scope 1 at $DIR/simplify-locals.rs:+2:14: +2:15
-          _0 = Add(move _1, const 1_u32);  // scope 1 at $DIR/simplify-locals.rs:+2:14: +2:19
-          StorageDead(_1);                 // scope 1 at $DIR/simplify-locals.rs:+2:18: +2:19
-          StorageDead(_2);                 // scope 0 at $DIR/simplify-locals.rs:+3:1: +3:2
-          return;                          // scope 0 at $DIR/simplify-locals.rs:+3:2: +3:2
+          StorageLive(_1);                 // scope 1 at $DIR/simplify_locals.rs:+2:14: +2:15
+          StorageLive(_2);                 // scope 1 at $DIR/simplify_locals.rs:+2:14: +2:15
+          _2 = &/*tls*/ mut X;             // scope 1 at $DIR/simplify_locals.rs:+2:14: +2:15
+          _1 = (*_2);                      // scope 1 at $DIR/simplify_locals.rs:+2:14: +2:15
+          _0 = Add(move _1, const 1_u32);  // scope 1 at $DIR/simplify_locals.rs:+2:14: +2:19
+          StorageDead(_1);                 // scope 1 at $DIR/simplify_locals.rs:+2:18: +2:19
+          StorageDead(_2);                 // scope 0 at $DIR/simplify_locals.rs:+3:1: +3:2
+          return;                          // scope 0 at $DIR/simplify_locals.rs:+3:2: +3:2
       }
   }
   
diff --git a/src/test/mir-opt/simplify_locals_fixedpoint.foo.SimplifyLocals.diff b/src/test/mir-opt/simplify_locals_fixedpoint.foo.SimplifyLocals.diff
index ac7a47ba58f7..8feddcef2cee 100644
--- a/src/test/mir-opt/simplify_locals_fixedpoint.foo.SimplifyLocals.diff
+++ b/src/test/mir-opt/simplify_locals_fixedpoint.foo.SimplifyLocals.diff
@@ -2,61 +2,61 @@
 + // MIR for `foo` after SimplifyLocals
   
   fn foo() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/simplify-locals-fixedpoint.rs:+0:13: +0:13
-      let mut _1: (std::option::Option<u8>, std::option::Option<T>); // in scope 0 at $DIR/simplify-locals-fixedpoint.rs:+1:30: +1:69
-      let mut _2: std::option::Option<u8>; // in scope 0 at $DIR/simplify-locals-fixedpoint.rs:+1:31: +1:49
-      let mut _3: std::option::Option<T>;  // in scope 0 at $DIR/simplify-locals-fixedpoint.rs:+1:51: +1:68
-      let mut _4: isize;                   // in scope 0 at $DIR/simplify-locals-fixedpoint.rs:+1:22: +1:26
-      let mut _5: isize;                   // in scope 0 at $DIR/simplify-locals-fixedpoint.rs:+1:13: +1:20
--     let mut _7: bool;                    // in scope 0 at $DIR/simplify-locals-fixedpoint.rs:+2:12: +2:20
--     let mut _8: u8;                      // in scope 0 at $DIR/simplify-locals-fixedpoint.rs:+2:12: +2:13
+      let mut _0: ();                      // return place in scope 0 at $DIR/simplify_locals_fixedpoint.rs:+0:13: +0:13
+      let mut _1: (std::option::Option<u8>, std::option::Option<T>); // in scope 0 at $DIR/simplify_locals_fixedpoint.rs:+1:30: +1:69
+      let mut _2: std::option::Option<u8>; // in scope 0 at $DIR/simplify_locals_fixedpoint.rs:+1:31: +1:49
+      let mut _3: std::option::Option<T>;  // in scope 0 at $DIR/simplify_locals_fixedpoint.rs:+1:51: +1:68
+      let mut _4: isize;                   // in scope 0 at $DIR/simplify_locals_fixedpoint.rs:+1:22: +1:26
+      let mut _5: isize;                   // in scope 0 at $DIR/simplify_locals_fixedpoint.rs:+1:13: +1:20
+-     let mut _7: bool;                    // in scope 0 at $DIR/simplify_locals_fixedpoint.rs:+2:12: +2:20
+-     let mut _8: u8;                      // in scope 0 at $DIR/simplify_locals_fixedpoint.rs:+2:12: +2:13
       scope 1 {
-          debug a => _6;                   // in scope 1 at $DIR/simplify-locals-fixedpoint.rs:+1:18: +1:19
-          let _6: u8;                      // in scope 1 at $DIR/simplify-locals-fixedpoint.rs:+1:18: +1:19
+          debug a => _6;                   // in scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:18: +1:19
+          let _6: u8;                      // in scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:18: +1:19
       }
   
       bb0: {
-          StorageLive(_1);                 // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+1:30: +1:69
-          StorageLive(_2);                 // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+1:31: +1:49
-          Deinit(_2);                      // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+1:31: +1:49
-          discriminant(_2) = 0;            // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+1:31: +1:49
-          StorageLive(_3);                 // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+1:51: +1:68
-          Deinit(_3);                      // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+1:51: +1:68
-          discriminant(_3) = 0;            // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+1:51: +1:68
-          Deinit(_1);                      // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+1:30: +1:69
-          (_1.0: std::option::Option<u8>) = move _2; // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+1:30: +1:69
-          (_1.1: std::option::Option<T>) = move _3; // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+1:30: +1:69
-          StorageDead(_3);                 // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+1:68: +1:69
-          StorageDead(_2);                 // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+1:68: +1:69
-          _5 = discriminant((_1.0: std::option::Option<u8>)); // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+1:12: +1:27
-          switchInt(move _5) -> [1_isize: bb1, otherwise: bb3]; // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+1:12: +1:27
+          StorageLive(_1);                 // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:30: +1:69
+          StorageLive(_2);                 // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:31: +1:49
+          Deinit(_2);                      // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:31: +1:49
+          discriminant(_2) = 0;            // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:31: +1:49
+          StorageLive(_3);                 // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:51: +1:68
+          Deinit(_3);                      // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:51: +1:68
+          discriminant(_3) = 0;            // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:51: +1:68
+          Deinit(_1);                      // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:30: +1:69
+          (_1.0: std::option::Option<u8>) = move _2; // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:30: +1:69
+          (_1.1: std::option::Option<T>) = move _3; // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:30: +1:69
+          StorageDead(_3);                 // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:68: +1:69
+          StorageDead(_2);                 // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:68: +1:69
+          _5 = discriminant((_1.0: std::option::Option<u8>)); // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:12: +1:27
+          switchInt(move _5) -> [1_isize: bb1, otherwise: bb3]; // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:12: +1:27
       }
   
       bb1: {
-          _4 = discriminant((_1.1: std::option::Option<T>)); // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+1:12: +1:27
-          switchInt(move _4) -> [0_isize: bb2, otherwise: bb3]; // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+1:12: +1:27
+          _4 = discriminant((_1.1: std::option::Option<T>)); // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:12: +1:27
+          switchInt(move _4) -> [0_isize: bb2, otherwise: bb3]; // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:12: +1:27
       }
   
       bb2: {
-          StorageLive(_6);                 // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+1:18: +1:19
-          _6 = (((_1.0: std::option::Option<u8>) as Some).0: u8); // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+1:18: +1:19
--         StorageLive(_7);                 // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+2:12: +2:20
--         StorageLive(_8);                 // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+2:12: +2:13
--         _8 = _6;                         // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+2:12: +2:13
--         _7 = Gt(move _8, const 42_u8);   // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+2:12: +2:20
--         StorageDead(_8);                 // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+2:19: +2:20
--         StorageDead(_7);                 // scope 1 at $DIR/simplify-locals-fixedpoint.rs:+4:9: +4:10
-          StorageDead(_6);                 // scope 0 at $DIR/simplify-locals-fixedpoint.rs:+5:5: +5:6
-          goto -> bb3;                     // scope 0 at $DIR/simplify-locals-fixedpoint.rs:+1:5: +5:6
+          StorageLive(_6);                 // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:18: +1:19
+          _6 = (((_1.0: std::option::Option<u8>) as Some).0: u8); // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:18: +1:19
+-         StorageLive(_7);                 // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+2:12: +2:20
+-         StorageLive(_8);                 // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+2:12: +2:13
+-         _8 = _6;                         // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+2:12: +2:13
+-         _7 = Gt(move _8, const 42_u8);   // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+2:12: +2:20
+-         StorageDead(_8);                 // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+2:19: +2:20
+-         StorageDead(_7);                 // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+4:9: +4:10
+          StorageDead(_6);                 // scope 0 at $DIR/simplify_locals_fixedpoint.rs:+5:5: +5:6
+          goto -> bb3;                     // scope 0 at $DIR/simplify_locals_fixedpoint.rs:+1:5: +5:6
       }
   
       bb3: {
-          drop(_1) -> bb4;                 // scope 0 at $DIR/simplify-locals-fixedpoint.rs:+6:1: +6:2
+          drop(_1) -> bb4;                 // scope 0 at $DIR/simplify_locals_fixedpoint.rs:+6:1: +6:2
       }
   
       bb4: {
-          StorageDead(_1);                 // scope 0 at $DIR/simplify-locals-fixedpoint.rs:+6:1: +6:2
-          return;                          // scope 0 at $DIR/simplify-locals-fixedpoint.rs:+6:2: +6:2
+          StorageDead(_1);                 // scope 0 at $DIR/simplify_locals_fixedpoint.rs:+6:1: +6:2
+          return;                          // scope 0 at $DIR/simplify_locals_fixedpoint.rs:+6:2: +6:2
       }
   }
   
diff --git a/src/test/mir-opt/simplify-locals-fixedpoint.rs b/src/test/mir-opt/simplify_locals_fixedpoint.rs
similarity index 100%
rename from src/test/mir-opt/simplify-locals-fixedpoint.rs
rename to src/test/mir-opt/simplify_locals_fixedpoint.rs
diff --git a/src/test/mir-opt/simplify_locals_removes_unused_consts.main.SimplifyLocals.diff b/src/test/mir-opt/simplify_locals_removes_unused_consts.main.SimplifyLocals.diff
index b41527ba02de..78272272b070 100644
--- a/src/test/mir-opt/simplify_locals_removes_unused_consts.main.SimplifyLocals.diff
+++ b/src/test/mir-opt/simplify_locals_removes_unused_consts.main.SimplifyLocals.diff
@@ -2,108 +2,108 @@
 + // MIR for `main` after SimplifyLocals
   
   fn main() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+0:11: +0:11
--     let mut _1: ((), ());                // in scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+1:20: +1:28
--     let mut _2: ();                      // in scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+1:21: +1:23
--     let mut _3: ();                      // in scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+1:25: +1:27
--     let _4: ();                          // in scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+2:5: +2:22
--     let mut _5: ((), ());                // in scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+2:13: +2:21
--     let mut _6: ();                      // in scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+2:14: +2:16
--     let mut _7: ();                      // in scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+2:18: +2:20
--     let _8: ();                          // in scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+4:5: +4:35
--     let mut _9: u8;                      // in scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+4:12: +4:34
--     let mut _10: u8;                     // in scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+4:12: +4:30
--     let mut _11: Temp;                   // in scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+4:12: +4:28
-+     let _1: ();                          // in scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+2:5: +2:22
-+     let mut _2: ((), ());                // in scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+2:13: +2:21
-+     let mut _3: ();                      // in scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+2:14: +2:16
-+     let mut _4: ();                      // in scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+2:18: +2:20
-+     let _5: ();                          // in scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+4:5: +4:35
-+     let mut _6: u8;                      // in scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+4:12: +4:34
-+     let mut _7: u8;                      // in scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+4:12: +4:30
-+     let mut _8: Temp;                    // in scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+4:12: +4:28
+      let mut _0: ();                      // return place in scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+0:11: +0:11
+-     let mut _1: ((), ());                // in scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:20: +1:28
+-     let mut _2: ();                      // in scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:21: +1:23
+-     let mut _3: ();                      // in scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:25: +1:27
+-     let _4: ();                          // in scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+2:5: +2:22
+-     let mut _5: ((), ());                // in scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+2:13: +2:21
+-     let mut _6: ();                      // in scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+2:14: +2:16
+-     let mut _7: ();                      // in scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+2:18: +2:20
+-     let _8: ();                          // in scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+4:5: +4:35
+-     let mut _9: u8;                      // in scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:34
+-     let mut _10: u8;                     // in scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:30
+-     let mut _11: Temp;                   // in scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:28
++     let _1: ();                          // in scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+2:5: +2:22
++     let mut _2: ((), ());                // in scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+2:13: +2:21
++     let mut _3: ();                      // in scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+2:14: +2:16
++     let mut _4: ();                      // in scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+2:18: +2:20
++     let _5: ();                          // in scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+4:5: +4:35
++     let mut _6: u8;                      // in scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:34
++     let mut _7: u8;                      // in scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:30
++     let mut _8: Temp;                    // in scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:28
       scope 1 {
       }
   
       bb0: {
--         StorageLive(_1);                 // scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+1:20: +1:28
--         StorageLive(_2);                 // scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+1:21: +1:23
--         Deinit(_2);                      // scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+1:21: +1:23
--         StorageLive(_3);                 // scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+1:25: +1:27
--         Deinit(_3);                      // scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+1:25: +1:27
--         Deinit(_1);                      // scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+1:20: +1:28
--         (_1.0: ()) = move _2;            // scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+1:20: +1:28
--         (_1.1: ()) = move _3;            // scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+1:20: +1:28
--         StorageDead(_3);                 // scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+1:27: +1:28
--         StorageDead(_2);                 // scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+1:27: +1:28
--         StorageDead(_1);                 // scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+1:28: +1:29
--         StorageLive(_4);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:5: +2:22
--         StorageLive(_5);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:13: +2:21
--         StorageLive(_6);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:14: +2:16
--         Deinit(_6);                      // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:14: +2:16
--         StorageLive(_7);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:18: +2:20
--         Deinit(_7);                      // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:18: +2:20
--         Deinit(_5);                      // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:13: +2:21
--         (_5.0: ()) = move _6;            // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:13: +2:21
--         (_5.1: ()) = move _7;            // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:13: +2:21
--         StorageDead(_7);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:20: +2:21
--         StorageDead(_6);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:20: +2:21
--         _4 = use_zst(move _5) -> bb1;    // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:5: +2:22
-+         StorageLive(_1);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:5: +2:22
-+         StorageLive(_2);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:13: +2:21
-+         StorageLive(_3);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:14: +2:16
-+         Deinit(_3);                      // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:14: +2:16
-+         StorageLive(_4);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:18: +2:20
-+         Deinit(_4);                      // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:18: +2:20
-+         Deinit(_2);                      // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:13: +2:21
-+         (_2.0: ()) = move _3;            // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:13: +2:21
-+         (_2.1: ()) = move _4;            // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:13: +2:21
-+         StorageDead(_4);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:20: +2:21
-+         StorageDead(_3);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:20: +2:21
-+         _1 = use_zst(move _2) -> bb1;    // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:5: +2:22
+-         StorageLive(_1);                 // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:20: +1:28
+-         StorageLive(_2);                 // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:21: +1:23
+-         Deinit(_2);                      // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:21: +1:23
+-         StorageLive(_3);                 // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:25: +1:27
+-         Deinit(_3);                      // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:25: +1:27
+-         Deinit(_1);                      // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:20: +1:28
+-         (_1.0: ()) = move _2;            // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:20: +1:28
+-         (_1.1: ()) = move _3;            // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:20: +1:28
+-         StorageDead(_3);                 // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:27: +1:28
+-         StorageDead(_2);                 // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:27: +1:28
+-         StorageDead(_1);                 // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:28: +1:29
+-         StorageLive(_4);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:5: +2:22
+-         StorageLive(_5);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:13: +2:21
+-         StorageLive(_6);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:14: +2:16
+-         Deinit(_6);                      // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:14: +2:16
+-         StorageLive(_7);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:18: +2:20
+-         Deinit(_7);                      // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:18: +2:20
+-         Deinit(_5);                      // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:13: +2:21
+-         (_5.0: ()) = move _6;            // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:13: +2:21
+-         (_5.1: ()) = move _7;            // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:13: +2:21
+-         StorageDead(_7);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:20: +2:21
+-         StorageDead(_6);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:20: +2:21
+-         _4 = use_zst(move _5) -> bb1;    // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:5: +2:22
++         StorageLive(_1);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:5: +2:22
++         StorageLive(_2);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:13: +2:21
++         StorageLive(_3);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:14: +2:16
++         Deinit(_3);                      // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:14: +2:16
++         StorageLive(_4);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:18: +2:20
++         Deinit(_4);                      // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:18: +2:20
++         Deinit(_2);                      // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:13: +2:21
++         (_2.0: ()) = move _3;            // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:13: +2:21
++         (_2.1: ()) = move _4;            // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:13: +2:21
++         StorageDead(_4);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:20: +2:21
++         StorageDead(_3);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:20: +2:21
++         _1 = use_zst(move _2) -> bb1;    // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:5: +2:22
                                            // mir::Constant
-                                           // + span: $DIR/simplify-locals-removes-unused-consts.rs:15:5: 15:12
+                                           // + span: $DIR/simplify_locals_removes_unused_consts.rs:15:5: 15:12
                                            // + literal: Const { ty: fn(((), ())) {use_zst}, val: Value(<ZST>) }
       }
   
       bb1: {
--         StorageDead(_5);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:21: +2:22
--         StorageDead(_4);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:22: +2:23
--         StorageLive(_8);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:5: +4:35
--         StorageLive(_9);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:12: +4:34
--         StorageLive(_10);                // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:12: +4:30
--         StorageLive(_11);                // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:12: +4:28
--         Deinit(_11);                     // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:12: +4:28
--         (_11.0: u8) = const 40_u8;       // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:12: +4:28
--         _10 = (_11.0: u8);               // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:12: +4:30
--         _9 = Add(move _10, const 2_u8);  // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:12: +4:34
--         StorageDead(_10);                // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:33: +4:34
--         _8 = use_u8(move _9) -> bb2;     // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:5: +4:35
-+         StorageDead(_2);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:21: +2:22
-+         StorageDead(_1);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+2:22: +2:23
-+         StorageLive(_5);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:5: +4:35
-+         StorageLive(_6);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:12: +4:34
-+         StorageLive(_7);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:12: +4:30
-+         StorageLive(_8);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:12: +4:28
-+         Deinit(_8);                      // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:12: +4:28
-+         (_8.0: u8) = const 40_u8;        // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:12: +4:28
-+         _7 = (_8.0: u8);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:12: +4:30
-+         _6 = Add(move _7, const 2_u8);   // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:12: +4:34
-+         StorageDead(_7);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:33: +4:34
-+         _5 = use_u8(move _6) -> bb2;     // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:5: +4:35
+-         StorageDead(_5);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:21: +2:22
+-         StorageDead(_4);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:22: +2:23
+-         StorageLive(_8);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:5: +4:35
+-         StorageLive(_9);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:34
+-         StorageLive(_10);                // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:30
+-         StorageLive(_11);                // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:28
+-         Deinit(_11);                     // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:28
+-         (_11.0: u8) = const 40_u8;       // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:28
+-         _10 = (_11.0: u8);               // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:30
+-         _9 = Add(move _10, const 2_u8);  // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:34
+-         StorageDead(_10);                // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:33: +4:34
+-         _8 = use_u8(move _9) -> bb2;     // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:5: +4:35
++         StorageDead(_2);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:21: +2:22
++         StorageDead(_1);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:22: +2:23
++         StorageLive(_5);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:5: +4:35
++         StorageLive(_6);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:34
++         StorageLive(_7);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:30
++         StorageLive(_8);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:28
++         Deinit(_8);                      // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:28
++         (_8.0: u8) = const 40_u8;        // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:28
++         _7 = (_8.0: u8);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:30
++         _6 = Add(move _7, const 2_u8);   // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:34
++         StorageDead(_7);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:33: +4:34
++         _5 = use_u8(move _6) -> bb2;     // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:5: +4:35
                                            // mir::Constant
-                                           // + span: $DIR/simplify-locals-removes-unused-consts.rs:17:5: 17:11
+                                           // + span: $DIR/simplify_locals_removes_unused_consts.rs:17:5: 17:11
                                            // + literal: Const { ty: fn(u8) {use_u8}, val: Value(<ZST>) }
       }
   
       bb2: {
--         StorageDead(_9);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:34: +4:35
--         StorageDead(_11);                // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:35: +4:36
-+         StorageDead(_6);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:34: +4:35
-          StorageDead(_8);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:35: +4:36
-+         StorageDead(_5);                 // scope 1 at $DIR/simplify-locals-removes-unused-consts.rs:+4:35: +4:36
-          _0 = const ();                   // scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+0:11: +5:2
-          return;                          // scope 0 at $DIR/simplify-locals-removes-unused-consts.rs:+5:2: +5:2
+-         StorageDead(_9);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:34: +4:35
+-         StorageDead(_11);                // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:35: +4:36
++         StorageDead(_6);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:34: +4:35
+          StorageDead(_8);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:35: +4:36
++         StorageDead(_5);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:35: +4:36
+          _0 = const ();                   // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+0:11: +5:2
+          return;                          // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+5:2: +5:2
       }
   }
   
diff --git a/src/test/mir-opt/simplify-locals-removes-unused-consts.rs b/src/test/mir-opt/simplify_locals_removes_unused_consts.rs
similarity index 100%
rename from src/test/mir-opt/simplify-locals-removes-unused-consts.rs
rename to src/test/mir-opt/simplify_locals_removes_unused_consts.rs
diff --git a/src/test/mir-opt/simplify_locals_removes_unused_discriminant_reads.map.SimplifyLocals.diff b/src/test/mir-opt/simplify_locals_removes_unused_discriminant_reads.map.SimplifyLocals.diff
index 51d26b08b2a1..6e7294003afa 100644
--- a/src/test/mir-opt/simplify_locals_removes_unused_discriminant_reads.map.SimplifyLocals.diff
+++ b/src/test/mir-opt/simplify_locals_removes_unused_discriminant_reads.map.SimplifyLocals.diff
@@ -2,51 +2,51 @@
 + // MIR for `map` after SimplifyLocals
   
   fn map(_1: Option<Box<()>>) -> Option<Box<()>> {
-      debug x => _1;                       // in scope 0 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+0:8: +0:9
-      let mut _0: std::option::Option<std::boxed::Box<()>>; // return place in scope 0 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+0:31: +0:46
-      let mut _2: isize;                   // in scope 0 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+2:9: +2:13
-      let _3: std::boxed::Box<()>;         // in scope 0 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+3:14: +3:15
-      let mut _4: std::boxed::Box<()>;     // in scope 0 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+3:25: +3:26
--     let mut _5: bool;                    // in scope 0 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+5:1: +5:2
--     let mut _6: isize;                   // in scope 0 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+5:1: +5:2
--     let mut _7: isize;                   // in scope 0 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+5:1: +5:2
+      debug x => _1;                       // in scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+0:8: +0:9
+      let mut _0: std::option::Option<std::boxed::Box<()>>; // return place in scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+0:31: +0:46
+      let mut _2: isize;                   // in scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+2:9: +2:13
+      let _3: std::boxed::Box<()>;         // in scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+3:14: +3:15
+      let mut _4: std::boxed::Box<()>;     // in scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+3:25: +3:26
+-     let mut _5: bool;                    // in scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+5:1: +5:2
+-     let mut _6: isize;                   // in scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+5:1: +5:2
+-     let mut _7: isize;                   // in scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+5:1: +5:2
       scope 1 {
-          debug x => _3;                   // in scope 1 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+3:14: +3:15
+          debug x => _3;                   // in scope 1 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+3:14: +3:15
       }
   
       bb0: {
--         _5 = const false;                // scope 0 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+1:11: +1:12
--         _5 = const true;                 // scope 0 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+1:11: +1:12
-          _2 = discriminant(_1);           // scope 0 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+1:11: +1:12
-          switchInt(move _2) -> [0_isize: bb3, 1_isize: bb1, otherwise: bb2]; // scope 0 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+1:5: +1:12
+-         _5 = const false;                // scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+1:11: +1:12
+-         _5 = const true;                 // scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+1:11: +1:12
+          _2 = discriminant(_1);           // scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+1:11: +1:12
+          switchInt(move _2) -> [0_isize: bb3, 1_isize: bb1, otherwise: bb2]; // scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+1:5: +1:12
       }
   
       bb1: {
-          StorageLive(_3);                 // scope 0 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+3:14: +3:15
-          _3 = move ((_1 as Some).0: std::boxed::Box<()>); // scope 0 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+3:14: +3:15
-          StorageLive(_4);                 // scope 1 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+3:25: +3:26
-          _4 = move _3;                    // scope 1 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+3:25: +3:26
-          Deinit(_0);                      // scope 1 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+3:20: +3:27
-          ((_0 as Some).0: std::boxed::Box<()>) = move _4; // scope 1 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+3:20: +3:27
-          discriminant(_0) = 1;            // scope 1 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+3:20: +3:27
-          StorageDead(_4);                 // scope 1 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+3:26: +3:27
-          StorageDead(_3);                 // scope 0 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+3:26: +3:27
-          goto -> bb4;                     // scope 0 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+3:26: +3:27
+          StorageLive(_3);                 // scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+3:14: +3:15
+          _3 = move ((_1 as Some).0: std::boxed::Box<()>); // scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+3:14: +3:15
+          StorageLive(_4);                 // scope 1 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+3:25: +3:26
+          _4 = move _3;                    // scope 1 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+3:25: +3:26
+          Deinit(_0);                      // scope 1 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+3:20: +3:27
+          ((_0 as Some).0: std::boxed::Box<()>) = move _4; // scope 1 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+3:20: +3:27
+          discriminant(_0) = 1;            // scope 1 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+3:20: +3:27
+          StorageDead(_4);                 // scope 1 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+3:26: +3:27
+          StorageDead(_3);                 // scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+3:26: +3:27
+          goto -> bb4;                     // scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+3:26: +3:27
       }
   
       bb2: {
-          unreachable;                     // scope 0 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+1:11: +1:12
+          unreachable;                     // scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+1:11: +1:12
       }
   
       bb3: {
-          Deinit(_0);                      // scope 0 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+2:17: +2:21
-          discriminant(_0) = 0;            // scope 0 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+2:17: +2:21
-          goto -> bb4;                     // scope 0 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+2:17: +2:21
+          Deinit(_0);                      // scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+2:17: +2:21
+          discriminant(_0) = 0;            // scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+2:17: +2:21
+          goto -> bb4;                     // scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+2:17: +2:21
       }
   
       bb4: {
--         _6 = discriminant(_1);           // scope 0 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+5:1: +5:2
-          return;                          // scope 0 at $DIR/simplify-locals-removes-unused-discriminant-reads.rs:+5:2: +5:2
+-         _6 = discriminant(_1);           // scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+5:1: +5:2
+          return;                          // scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+5:2: +5:2
       }
   }
   
diff --git a/src/test/mir-opt/simplify-locals-removes-unused-discriminant-reads.rs b/src/test/mir-opt/simplify_locals_removes_unused_discriminant_reads.rs
similarity index 100%
rename from src/test/mir-opt/simplify-locals-removes-unused-discriminant-reads.rs
rename to src/test/mir-opt/simplify_locals_removes_unused_discriminant_reads.rs
diff --git a/src/test/mir-opt/simplify_try.try_identity.DestinationPropagation.diff b/src/test/mir-opt/simplify_try.try_identity.DestinationPropagation.diff
deleted file mode 100644
index 83b91309be30..000000000000
--- a/src/test/mir-opt/simplify_try.try_identity.DestinationPropagation.diff
+++ /dev/null
@@ -1,106 +0,0 @@
-- // MIR for `try_identity` before DestinationPropagation
-+ // MIR for `try_identity` after DestinationPropagation
-  
-  fn try_identity(_1: Result<u32, i32>) -> Result<u32, i32> {
-      debug x => _1;                       // in scope 0 at $DIR/simplify_try.rs:+0:17: +0:18
-      let mut _0: std::result::Result<u32, i32>; // return place in scope 0 at $DIR/simplify_try.rs:+0:41: +0:57
-      let _2: u32;                         // in scope 0 at $DIR/simplify_try.rs:+1:9: +1:10
-      let mut _3: std::result::Result<u32, i32>; // in scope 0 at $DIR/simplify_try.rs:+1:19: +1:33
-      let mut _4: std::result::Result<u32, i32>; // in scope 0 at $DIR/simplify_try.rs:+1:31: +1:32
-      let mut _5: isize;                   // in scope 0 at $DIR/simplify_try.rs:+2:9: +2:15
-      let _6: i32;                         // in scope 0 at $DIR/simplify_try.rs:+2:13: +2:14
-      let mut _7: !;                       // in scope 0 at $DIR/simplify_try.rs:+2:19: +2:51
-      let mut _8: i32;                     // in scope 0 at $DIR/simplify_try.rs:+2:37: +2:50
-      let mut _9: i32;                     // in scope 0 at $DIR/simplify_try.rs:+2:48: +2:49
-      let _10: u32;                        // in scope 0 at $DIR/simplify_try.rs:+3:12: +3:13
-      let mut _11: u32;                    // in scope 0 at $DIR/simplify_try.rs:+5:8: +5:9
-      scope 1 {
--         debug y => _2;                   // in scope 1 at $DIR/simplify_try.rs:+1:9: +1:10
-+         debug y => ((_0 as Ok).0: u32);  // in scope 1 at $DIR/simplify_try.rs:+1:9: +1:10
-      }
-      scope 2 {
-          debug e => _6;                   // in scope 2 at $DIR/simplify_try.rs:+2:13: +2:14
-          scope 5 (inlined <i32 as From<i32>>::from) { // at $DIR/simplify_try.rs:22:37: 22:50
-              debug t => _9;               // in scope 5 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
-          }
-          scope 6 (inlined from_error::<u32, i32>) { // at $DIR/simplify_try.rs:22:26: 22:51
-              debug e => _8;               // in scope 6 at $DIR/simplify_try.rs:12:21: 12:22
-          }
-      }
-      scope 3 {
--         debug v => _10;                  // in scope 3 at $DIR/simplify_try.rs:+3:12: +3:13
-+         debug v => ((_0 as Ok).0: u32);  // in scope 3 at $DIR/simplify_try.rs:+3:12: +3:13
-      }
-      scope 4 (inlined into_result::<u32, i32>) { // at $DIR/simplify_try.rs:21:19: 21:33
--         debug r => _4;                   // in scope 4 at $DIR/simplify_try.rs:8:22: 8:23
-+         debug r => _3;                   // in scope 4 at $DIR/simplify_try.rs:8:22: 8:23
-      }
-  
-      bb0: {
--         StorageLive(_2);                 // scope 0 at $DIR/simplify_try.rs:+1:9: +1:10
--         StorageLive(_3);                 // scope 0 at $DIR/simplify_try.rs:+1:19: +1:33
--         StorageLive(_4);                 // scope 0 at $DIR/simplify_try.rs:+1:31: +1:32
--         _4 = _1;                         // scope 0 at $DIR/simplify_try.rs:+1:31: +1:32
--         _3 = move _4;                    // scope 4 at $DIR/simplify_try.rs:9:5: 9:6
--         StorageDead(_4);                 // scope 0 at $DIR/simplify_try.rs:+1:32: +1:33
-+         nop;                             // scope 0 at $DIR/simplify_try.rs:+1:9: +1:10
-+         nop;                             // scope 0 at $DIR/simplify_try.rs:+1:19: +1:33
-+         nop;                             // scope 0 at $DIR/simplify_try.rs:+1:31: +1:32
-+         _3 = _1;                         // scope 0 at $DIR/simplify_try.rs:+1:31: +1:32
-+         nop;                             // scope 4 at $DIR/simplify_try.rs:9:5: 9:6
-+         nop;                             // scope 0 at $DIR/simplify_try.rs:+1:32: +1:33
-          _5 = discriminant(_3);           // scope 0 at $DIR/simplify_try.rs:+1:19: +1:33
-          switchInt(move _5) -> [0_isize: bb1, 1_isize: bb3, otherwise: bb2]; // scope 0 at $DIR/simplify_try.rs:+1:13: +1:33
-      }
-  
-      bb1: {
--         StorageLive(_10);                // scope 0 at $DIR/simplify_try.rs:+3:12: +3:13
--         _10 = ((_3 as Ok).0: u32);       // scope 0 at $DIR/simplify_try.rs:+3:12: +3:13
--         _2 = _10;                        // scope 3 at $DIR/simplify_try.rs:+3:18: +3:19
--         StorageDead(_10);                // scope 0 at $DIR/simplify_try.rs:+3:18: +3:19
--         StorageDead(_3);                 // scope 0 at $DIR/simplify_try.rs:+4:6: +4:7
--         StorageLive(_11);                // scope 1 at $DIR/simplify_try.rs:+5:8: +5:9
--         _11 = _2;                        // scope 1 at $DIR/simplify_try.rs:+5:8: +5:9
-+         nop;                             // scope 0 at $DIR/simplify_try.rs:+3:12: +3:13
-+         ((_0 as Ok).0: u32) = ((_3 as Ok).0: u32); // scope 0 at $DIR/simplify_try.rs:+3:12: +3:13
-+         nop;                             // scope 3 at $DIR/simplify_try.rs:+3:18: +3:19
-+         nop;                             // scope 0 at $DIR/simplify_try.rs:+3:18: +3:19
-+         nop;                             // scope 0 at $DIR/simplify_try.rs:+4:6: +4:7
-+         nop;                             // scope 1 at $DIR/simplify_try.rs:+5:8: +5:9
-+         nop;                             // scope 1 at $DIR/simplify_try.rs:+5:8: +5:9
-          Deinit(_0);                      // scope 1 at $DIR/simplify_try.rs:+5:5: +5:10
--         ((_0 as Ok).0: u32) = move _11;  // scope 1 at $DIR/simplify_try.rs:+5:5: +5:10
-+         nop;                             // scope 1 at $DIR/simplify_try.rs:+5:5: +5:10
-          discriminant(_0) = 0;            // scope 1 at $DIR/simplify_try.rs:+5:5: +5:10
--         StorageDead(_11);                // scope 1 at $DIR/simplify_try.rs:+5:9: +5:10
--         StorageDead(_2);                 // scope 0 at $DIR/simplify_try.rs:+6:1: +6:2
-+         nop;                             // scope 1 at $DIR/simplify_try.rs:+5:9: +5:10
-+         nop;                             // scope 0 at $DIR/simplify_try.rs:+6:1: +6:2
-          return;                          // scope 0 at $DIR/simplify_try.rs:+6:2: +6:2
-      }
-  
-      bb2: {
-          unreachable;                     // scope 0 at $DIR/simplify_try.rs:+1:19: +1:33
-      }
-  
-      bb3: {
-          StorageLive(_6);                 // scope 0 at $DIR/simplify_try.rs:+2:13: +2:14
-          nop;                             // scope 0 at $DIR/simplify_try.rs:+2:13: +2:14
-          StorageLive(_8);                 // scope 2 at $DIR/simplify_try.rs:+2:37: +2:50
-          StorageLive(_9);                 // scope 2 at $DIR/simplify_try.rs:+2:48: +2:49
-          nop;                             // scope 2 at $DIR/simplify_try.rs:+2:48: +2:49
-          nop;                             // scope 5 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
-          StorageDead(_9);                 // scope 2 at $DIR/simplify_try.rs:+2:49: +2:50
-          nop;                             // scope 6 at $DIR/simplify_try.rs:13:9: 13:10
-          Deinit(_0);                      // scope 6 at $DIR/simplify_try.rs:13:5: 13:11
-          discriminant(_0) = 1;            // scope 6 at $DIR/simplify_try.rs:13:5: 13:11
-          StorageDead(_8);                 // scope 2 at $DIR/simplify_try.rs:+2:50: +2:51
-          StorageDead(_6);                 // scope 0 at $DIR/simplify_try.rs:+2:50: +2:51
--         StorageDead(_3);                 // scope 0 at $DIR/simplify_try.rs:+4:6: +4:7
--         StorageDead(_2);                 // scope 0 at $DIR/simplify_try.rs:+6:1: +6:2
-+         nop;                             // scope 0 at $DIR/simplify_try.rs:+4:6: +4:7
-+         nop;                             // scope 0 at $DIR/simplify_try.rs:+6:1: +6:2
-          return;                          // scope 0 at $DIR/simplify_try.rs:+6:2: +6:2
-      }
-  }
-  
diff --git a/src/test/mir-opt/simplify_try.try_identity.SimplifyArmIdentity.diff b/src/test/mir-opt/simplify_try.try_identity.SimplifyArmIdentity.diff
deleted file mode 100644
index e025ae7c5511..000000000000
--- a/src/test/mir-opt/simplify_try.try_identity.SimplifyArmIdentity.diff
+++ /dev/null
@@ -1,85 +0,0 @@
-- // MIR for `try_identity` before SimplifyArmIdentity
-+ // MIR for `try_identity` after SimplifyArmIdentity
-  
-  fn try_identity(_1: Result<u32, i32>) -> Result<u32, i32> {
-      debug x => _1;                       // in scope 0 at $DIR/simplify_try.rs:+0:17: +0:18
-      let mut _0: std::result::Result<u32, i32>; // return place in scope 0 at $DIR/simplify_try.rs:+0:41: +0:57
-      let _2: u32;                         // in scope 0 at $DIR/simplify_try.rs:+1:9: +1:10
-      let mut _3: std::result::Result<u32, i32>; // in scope 0 at $DIR/simplify_try.rs:+1:19: +1:33
-      let mut _4: std::result::Result<u32, i32>; // in scope 0 at $DIR/simplify_try.rs:+1:31: +1:32
-      let mut _5: isize;                   // in scope 0 at $DIR/simplify_try.rs:+2:9: +2:15
-      let _6: i32;                         // in scope 0 at $DIR/simplify_try.rs:+2:13: +2:14
-      let mut _7: !;                       // in scope 0 at $DIR/simplify_try.rs:+2:19: +2:51
-      let mut _8: i32;                     // in scope 0 at $DIR/simplify_try.rs:+2:37: +2:50
-      let mut _9: i32;                     // in scope 0 at $DIR/simplify_try.rs:+2:48: +2:49
-      let _10: u32;                        // in scope 0 at $DIR/simplify_try.rs:+3:12: +3:13
-      let mut _11: u32;                    // in scope 0 at $DIR/simplify_try.rs:+5:8: +5:9
-      scope 1 {
-          debug y => _2;                   // in scope 1 at $DIR/simplify_try.rs:+1:9: +1:10
-      }
-      scope 2 {
-          debug e => _6;                   // in scope 2 at $DIR/simplify_try.rs:+2:13: +2:14
-          scope 5 (inlined <i32 as From<i32>>::from) { // at $DIR/simplify_try.rs:22:37: 22:50
-              debug t => _9;               // in scope 5 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
-          }
-          scope 6 (inlined from_error::<u32, i32>) { // at $DIR/simplify_try.rs:22:26: 22:51
-              debug e => _8;               // in scope 6 at $DIR/simplify_try.rs:12:21: 12:22
-          }
-      }
-      scope 3 {
-          debug v => _10;                  // in scope 3 at $DIR/simplify_try.rs:+3:12: +3:13
-      }
-      scope 4 (inlined into_result::<u32, i32>) { // at $DIR/simplify_try.rs:21:19: 21:33
-          debug r => _4;                   // in scope 4 at $DIR/simplify_try.rs:8:22: 8:23
-      }
-  
-      bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/simplify_try.rs:+1:9: +1:10
-          StorageLive(_3);                 // scope 0 at $DIR/simplify_try.rs:+1:19: +1:33
-          StorageLive(_4);                 // scope 0 at $DIR/simplify_try.rs:+1:31: +1:32
-          _4 = _1;                         // scope 0 at $DIR/simplify_try.rs:+1:31: +1:32
-          _3 = move _4;                    // scope 4 at $DIR/simplify_try.rs:9:5: 9:6
-          StorageDead(_4);                 // scope 0 at $DIR/simplify_try.rs:+1:32: +1:33
-          _5 = discriminant(_3);           // scope 0 at $DIR/simplify_try.rs:+1:19: +1:33
-          switchInt(move _5) -> [0_isize: bb1, 1_isize: bb3, otherwise: bb2]; // scope 0 at $DIR/simplify_try.rs:+1:13: +1:33
-      }
-  
-      bb1: {
-          StorageLive(_10);                // scope 0 at $DIR/simplify_try.rs:+3:12: +3:13
-          _10 = ((_3 as Ok).0: u32);       // scope 0 at $DIR/simplify_try.rs:+3:12: +3:13
-          _2 = _10;                        // scope 3 at $DIR/simplify_try.rs:+3:18: +3:19
-          StorageDead(_10);                // scope 0 at $DIR/simplify_try.rs:+3:18: +3:19
-          StorageDead(_3);                 // scope 0 at $DIR/simplify_try.rs:+4:6: +4:7
-          StorageLive(_11);                // scope 1 at $DIR/simplify_try.rs:+5:8: +5:9
-          _11 = _2;                        // scope 1 at $DIR/simplify_try.rs:+5:8: +5:9
-          Deinit(_0);                      // scope 1 at $DIR/simplify_try.rs:+5:5: +5:10
-          ((_0 as Ok).0: u32) = move _11;  // scope 1 at $DIR/simplify_try.rs:+5:5: +5:10
-          discriminant(_0) = 0;            // scope 1 at $DIR/simplify_try.rs:+5:5: +5:10
-          StorageDead(_11);                // scope 1 at $DIR/simplify_try.rs:+5:9: +5:10
-          StorageDead(_2);                 // scope 0 at $DIR/simplify_try.rs:+6:1: +6:2
-          return;                          // scope 0 at $DIR/simplify_try.rs:+6:2: +6:2
-      }
-  
-      bb2: {
-          unreachable;                     // scope 0 at $DIR/simplify_try.rs:+1:19: +1:33
-      }
-  
-      bb3: {
-          StorageLive(_6);                 // scope 0 at $DIR/simplify_try.rs:+2:13: +2:14
-          _6 = ((_3 as Err).0: i32);       // scope 0 at $DIR/simplify_try.rs:+2:13: +2:14
-          StorageLive(_8);                 // scope 2 at $DIR/simplify_try.rs:+2:37: +2:50
-          StorageLive(_9);                 // scope 2 at $DIR/simplify_try.rs:+2:48: +2:49
-          _9 = _6;                         // scope 2 at $DIR/simplify_try.rs:+2:48: +2:49
-          _8 = move _9;                    // scope 5 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
-          StorageDead(_9);                 // scope 2 at $DIR/simplify_try.rs:+2:49: +2:50
-          ((_0 as Err).0: i32) = move _8;  // scope 6 at $DIR/simplify_try.rs:13:9: 13:10
-          Deinit(_0);                      // scope 6 at $DIR/simplify_try.rs:13:5: 13:11
-          discriminant(_0) = 1;            // scope 6 at $DIR/simplify_try.rs:13:5: 13:11
-          StorageDead(_8);                 // scope 2 at $DIR/simplify_try.rs:+2:50: +2:51
-          StorageDead(_6);                 // scope 0 at $DIR/simplify_try.rs:+2:50: +2:51
-          StorageDead(_3);                 // scope 0 at $DIR/simplify_try.rs:+4:6: +4:7
-          StorageDead(_2);                 // scope 0 at $DIR/simplify_try.rs:+6:1: +6:2
-          return;                          // scope 0 at $DIR/simplify_try.rs:+6:2: +6:2
-      }
-  }
-  
diff --git a/src/test/mir-opt/simplify_try.try_identity.SimplifyBranchSame.after.mir b/src/test/mir-opt/simplify_try.try_identity.SimplifyBranchSame.after.mir
deleted file mode 100644
index eb5af2227ec9..000000000000
--- a/src/test/mir-opt/simplify_try.try_identity.SimplifyBranchSame.after.mir
+++ /dev/null
@@ -1,83 +0,0 @@
-// MIR for `try_identity` after SimplifyBranchSame
-
-fn try_identity(_1: Result<u32, i32>) -> Result<u32, i32> {
-    debug x => _1;                       // in scope 0 at $DIR/simplify_try.rs:+0:17: +0:18
-    let mut _0: std::result::Result<u32, i32>; // return place in scope 0 at $DIR/simplify_try.rs:+0:41: +0:57
-    let _2: u32;                         // in scope 0 at $DIR/simplify_try.rs:+1:9: +1:10
-    let mut _3: std::result::Result<u32, i32>; // in scope 0 at $DIR/simplify_try.rs:+1:19: +1:33
-    let mut _4: std::result::Result<u32, i32>; // in scope 0 at $DIR/simplify_try.rs:+1:31: +1:32
-    let mut _5: isize;                   // in scope 0 at $DIR/simplify_try.rs:+2:9: +2:15
-    let _6: i32;                         // in scope 0 at $DIR/simplify_try.rs:+2:13: +2:14
-    let mut _7: !;                       // in scope 0 at $DIR/simplify_try.rs:+2:19: +2:51
-    let mut _8: i32;                     // in scope 0 at $DIR/simplify_try.rs:+2:37: +2:50
-    let mut _9: i32;                     // in scope 0 at $DIR/simplify_try.rs:+2:48: +2:49
-    let _10: u32;                        // in scope 0 at $DIR/simplify_try.rs:+3:12: +3:13
-    let mut _11: u32;                    // in scope 0 at $DIR/simplify_try.rs:+5:8: +5:9
-    scope 1 {
-        debug y => _2;                   // in scope 1 at $DIR/simplify_try.rs:+1:9: +1:10
-    }
-    scope 2 {
-        debug e => _6;                   // in scope 2 at $DIR/simplify_try.rs:+2:13: +2:14
-        scope 5 (inlined <i32 as From<i32>>::from) { // at $DIR/simplify_try.rs:22:37: 22:50
-            debug t => _9;               // in scope 5 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
-        }
-        scope 6 (inlined from_error::<u32, i32>) { // at $DIR/simplify_try.rs:22:26: 22:51
-            debug e => _8;               // in scope 6 at $DIR/simplify_try.rs:12:21: 12:22
-        }
-    }
-    scope 3 {
-        debug v => _10;                  // in scope 3 at $DIR/simplify_try.rs:+3:12: +3:13
-    }
-    scope 4 (inlined into_result::<u32, i32>) { // at $DIR/simplify_try.rs:21:19: 21:33
-        debug r => _4;                   // in scope 4 at $DIR/simplify_try.rs:8:22: 8:23
-    }
-
-    bb0: {
-        StorageLive(_2);                 // scope 0 at $DIR/simplify_try.rs:+1:9: +1:10
-        StorageLive(_3);                 // scope 0 at $DIR/simplify_try.rs:+1:19: +1:33
-        StorageLive(_4);                 // scope 0 at $DIR/simplify_try.rs:+1:31: +1:32
-        _4 = _1;                         // scope 0 at $DIR/simplify_try.rs:+1:31: +1:32
-        _3 = move _4;                    // scope 4 at $DIR/simplify_try.rs:9:5: 9:6
-        StorageDead(_4);                 // scope 0 at $DIR/simplify_try.rs:+1:32: +1:33
-        _5 = discriminant(_3);           // scope 0 at $DIR/simplify_try.rs:+1:19: +1:33
-        switchInt(move _5) -> [0_isize: bb1, 1_isize: bb3, otherwise: bb2]; // scope 0 at $DIR/simplify_try.rs:+1:13: +1:33
-    }
-
-    bb1: {
-        StorageLive(_10);                // scope 0 at $DIR/simplify_try.rs:+3:12: +3:13
-        _10 = ((_3 as Ok).0: u32);       // scope 0 at $DIR/simplify_try.rs:+3:12: +3:13
-        _2 = _10;                        // scope 3 at $DIR/simplify_try.rs:+3:18: +3:19
-        StorageDead(_10);                // scope 0 at $DIR/simplify_try.rs:+3:18: +3:19
-        StorageDead(_3);                 // scope 0 at $DIR/simplify_try.rs:+4:6: +4:7
-        StorageLive(_11);                // scope 1 at $DIR/simplify_try.rs:+5:8: +5:9
-        _11 = _2;                        // scope 1 at $DIR/simplify_try.rs:+5:8: +5:9
-        Deinit(_0);                      // scope 1 at $DIR/simplify_try.rs:+5:5: +5:10
-        ((_0 as Ok).0: u32) = move _11;  // scope 1 at $DIR/simplify_try.rs:+5:5: +5:10
-        discriminant(_0) = 0;            // scope 1 at $DIR/simplify_try.rs:+5:5: +5:10
-        StorageDead(_11);                // scope 1 at $DIR/simplify_try.rs:+5:9: +5:10
-        StorageDead(_2);                 // scope 0 at $DIR/simplify_try.rs:+6:1: +6:2
-        return;                          // scope 0 at $DIR/simplify_try.rs:+6:2: +6:2
-    }
-
-    bb2: {
-        unreachable;                     // scope 0 at $DIR/simplify_try.rs:+1:19: +1:33
-    }
-
-    bb3: {
-        StorageLive(_6);                 // scope 0 at $DIR/simplify_try.rs:+2:13: +2:14
-        _6 = ((_3 as Err).0: i32);       // scope 0 at $DIR/simplify_try.rs:+2:13: +2:14
-        StorageLive(_8);                 // scope 2 at $DIR/simplify_try.rs:+2:37: +2:50
-        StorageLive(_9);                 // scope 2 at $DIR/simplify_try.rs:+2:48: +2:49
-        _9 = _6;                         // scope 2 at $DIR/simplify_try.rs:+2:48: +2:49
-        _8 = move _9;                    // scope 5 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
-        StorageDead(_9);                 // scope 2 at $DIR/simplify_try.rs:+2:49: +2:50
-        ((_0 as Err).0: i32) = move _8;  // scope 6 at $DIR/simplify_try.rs:13:9: 13:10
-        Deinit(_0);                      // scope 6 at $DIR/simplify_try.rs:13:5: 13:11
-        discriminant(_0) = 1;            // scope 6 at $DIR/simplify_try.rs:13:5: 13:11
-        StorageDead(_8);                 // scope 2 at $DIR/simplify_try.rs:+2:50: +2:51
-        StorageDead(_6);                 // scope 0 at $DIR/simplify_try.rs:+2:50: +2:51
-        StorageDead(_3);                 // scope 0 at $DIR/simplify_try.rs:+4:6: +4:7
-        StorageDead(_2);                 // scope 0 at $DIR/simplify_try.rs:+6:1: +6:2
-        return;                          // scope 0 at $DIR/simplify_try.rs:+6:2: +6:2
-    }
-}
diff --git a/src/test/mir-opt/simplify_try.try_identity.SimplifyLocals.after.mir b/src/test/mir-opt/simplify_try.try_identity.SimplifyLocals.after.mir
deleted file mode 100644
index 1efa8a67e5cd..000000000000
--- a/src/test/mir-opt/simplify_try.try_identity.SimplifyLocals.after.mir
+++ /dev/null
@@ -1,58 +0,0 @@
-// MIR for `try_identity` after SimplifyLocals
-
-fn try_identity(_1: Result<u32, i32>) -> Result<u32, i32> {
-    debug x => _1;                       // in scope 0 at $DIR/simplify_try.rs:+0:17: +0:18
-    let mut _0: std::result::Result<u32, i32>; // return place in scope 0 at $DIR/simplify_try.rs:+0:41: +0:57
-    let mut _2: std::result::Result<u32, i32>; // in scope 0 at $DIR/simplify_try.rs:+1:19: +1:33
-    let mut _3: isize;                   // in scope 0 at $DIR/simplify_try.rs:+2:9: +2:15
-    let _4: i32;                         // in scope 0 at $DIR/simplify_try.rs:+2:13: +2:14
-    let mut _5: i32;                     // in scope 0 at $DIR/simplify_try.rs:+2:37: +2:50
-    let mut _6: i32;                     // in scope 0 at $DIR/simplify_try.rs:+2:48: +2:49
-    scope 1 {
-        debug y => ((_0 as Ok).0: u32);  // in scope 1 at $DIR/simplify_try.rs:+1:9: +1:10
-    }
-    scope 2 {
-        debug e => _4;                   // in scope 2 at $DIR/simplify_try.rs:+2:13: +2:14
-        scope 5 (inlined <i32 as From<i32>>::from) { // at $DIR/simplify_try.rs:22:37: 22:50
-            debug t => _6;               // in scope 5 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
-        }
-        scope 6 (inlined from_error::<u32, i32>) { // at $DIR/simplify_try.rs:22:26: 22:51
-            debug e => _5;               // in scope 6 at $DIR/simplify_try.rs:12:21: 12:22
-        }
-    }
-    scope 3 {
-        debug v => ((_0 as Ok).0: u32);  // in scope 3 at $DIR/simplify_try.rs:+3:12: +3:13
-    }
-    scope 4 (inlined into_result::<u32, i32>) { // at $DIR/simplify_try.rs:21:19: 21:33
-        debug r => _2;                   // in scope 4 at $DIR/simplify_try.rs:8:22: 8:23
-    }
-
-    bb0: {
-        _2 = _1;                         // scope 0 at $DIR/simplify_try.rs:+1:31: +1:32
-        _3 = discriminant(_2);           // scope 0 at $DIR/simplify_try.rs:+1:19: +1:33
-        switchInt(move _3) -> [0_isize: bb1, 1_isize: bb3, otherwise: bb2]; // scope 0 at $DIR/simplify_try.rs:+1:13: +1:33
-    }
-
-    bb1: {
-        ((_0 as Ok).0: u32) = ((_2 as Ok).0: u32); // scope 0 at $DIR/simplify_try.rs:+3:12: +3:13
-        Deinit(_0);                      // scope 1 at $DIR/simplify_try.rs:+5:5: +5:10
-        discriminant(_0) = 0;            // scope 1 at $DIR/simplify_try.rs:+5:5: +5:10
-        return;                          // scope 0 at $DIR/simplify_try.rs:+6:2: +6:2
-    }
-
-    bb2: {
-        unreachable;                     // scope 0 at $DIR/simplify_try.rs:+1:19: +1:33
-    }
-
-    bb3: {
-        StorageLive(_4);                 // scope 0 at $DIR/simplify_try.rs:+2:13: +2:14
-        StorageLive(_5);                 // scope 2 at $DIR/simplify_try.rs:+2:37: +2:50
-        StorageLive(_6);                 // scope 2 at $DIR/simplify_try.rs:+2:48: +2:49
-        StorageDead(_6);                 // scope 2 at $DIR/simplify_try.rs:+2:49: +2:50
-        Deinit(_0);                      // scope 6 at $DIR/simplify_try.rs:13:5: 13:11
-        discriminant(_0) = 1;            // scope 6 at $DIR/simplify_try.rs:13:5: 13:11
-        StorageDead(_5);                 // scope 2 at $DIR/simplify_try.rs:+2:50: +2:51
-        StorageDead(_4);                 // scope 0 at $DIR/simplify_try.rs:+2:50: +2:51
-        return;                          // scope 0 at $DIR/simplify_try.rs:+6:2: +6:2
-    }
-}
diff --git a/src/test/mir-opt/slice-drop-shim.rs b/src/test/mir-opt/slice_drop_shim.rs
similarity index 100%
rename from src/test/mir-opt/slice-drop-shim.rs
rename to src/test/mir-opt/slice_drop_shim.rs
diff --git a/src/test/mir-opt/spanview_block.main.mir_map.0.html b/src/test/mir-opt/spanview_block.main.built.after.html
similarity index 96%
rename from src/test/mir-opt/spanview_block.main.mir_map.0.html
rename to src/test/mir-opt/spanview_block.main.built.after.html
index 8e5268043e70..b962d80c59e5 100644
--- a/src/test/mir-opt/spanview_block.main.mir_map.0.html
+++ b/src/test/mir-opt/spanview_block.main.built.after.html
@@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html>
 <head>
-<title>spanview_block.main.mir_map.0</title>
+<title>spanview_block.main.built.after</title>
 <style>
     .line {
         counter-increment: line;
@@ -59,7 +59,7 @@
 </style>
 </head>
 <body>
-<div class="code" style="counter-reset: line 4"><span class="line"><span class="code" style="--layer: 0">fn main() </span><span><span class="code even" style="--layer: 1" title="0: $DIR/spanview-block.rs:5:11: 5:13:
+<div class="code" style="counter-reset: line 4"><span class="line"><span class="code" style="--layer: 0">fn main() </span><span><span class="code even" style="--layer: 1" title="0: $DIR/spanview_block.rs:5:11: 5:13:
     5:11-5:13: Assign: _0 = const ()
     5:13-5:13: Return: return"><span class="annotation">0⦊</span>{}<span class="annotation">⦉0</span></span></span></span></div>
 </body>
diff --git a/src/test/mir-opt/spanview-block.rs b/src/test/mir-opt/spanview_block.rs
similarity index 64%
rename from src/test/mir-opt/spanview-block.rs
rename to src/test/mir-opt/spanview_block.rs
index fc1d6e0ede66..0ecf35ad6a2e 100644
--- a/src/test/mir-opt/spanview-block.rs
+++ b/src/test/mir-opt/spanview_block.rs
@@ -1,5 +1,5 @@
 // Test spanview block output
 // compile-flags: -Z dump-mir-spanview=block
 
-// EMIT_MIR spanview_block.main.mir_map.0.html
+// EMIT_MIR spanview_block.main.built.after.html
 fn main() {}
diff --git a/src/test/mir-opt/spanview_statement.main.mir_map.0.html b/src/test/mir-opt/spanview_statement.main.built.after.html
similarity index 94%
rename from src/test/mir-opt/spanview_statement.main.mir_map.0.html
rename to src/test/mir-opt/spanview_statement.main.built.after.html
index abbff2270b7f..43bff7d096e2 100644
--- a/src/test/mir-opt/spanview_statement.main.mir_map.0.html
+++ b/src/test/mir-opt/spanview_statement.main.built.after.html
@@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html>
 <head>
-<title>spanview_statement.main.mir_map.0</title>
+<title>spanview_statement.main.built.after</title>
 <style>
     .line {
         counter-increment: line;
@@ -59,8 +59,8 @@
 </style>
 </head>
 <body>
-<div class="code" style="counter-reset: line 4"><span class="line"><span class="code" style="--layer: 0">fn main() </span><span><span class="code even" style="--layer: 1" title="0[0]: $DIR/spanview-statement.rs:5:11: 5:13:
-    5:11-5:13: Assign: _0 = const ()"><span class="annotation">0[0]⦊</span>{}<span class="annotation">⦉0[0]</span></span></span><span><span class="code odd" style="--layer: 1" title="0:Return: $DIR/spanview-statement.rs:5:13: 5:13:
+<div class="code" style="counter-reset: line 4"><span class="line"><span class="code" style="--layer: 0">fn main() </span><span><span class="code even" style="--layer: 1" title="0[0]: $DIR/spanview_statement.rs:5:11: 5:13:
+    5:11-5:13: Assign: _0 = const ()"><span class="annotation">0[0]⦊</span>{}<span class="annotation">⦉0[0]</span></span></span><span><span class="code odd" style="--layer: 1" title="0:Return: $DIR/spanview_statement.rs:5:13: 5:13:
     5:13-5:13: Return: return"><span class="annotation">0:Return⦊</span>‸<span class="annotation">⦉0:Return</span></span></span></span></div>
 </body>
 </html>
diff --git a/src/test/mir-opt/spanview-statement.rs b/src/test/mir-opt/spanview_statement.rs
similarity index 72%
rename from src/test/mir-opt/spanview-statement.rs
rename to src/test/mir-opt/spanview_statement.rs
index a43ad5e71a39..457052617b78 100644
--- a/src/test/mir-opt/spanview-statement.rs
+++ b/src/test/mir-opt/spanview_statement.rs
@@ -1,5 +1,5 @@
 // Test spanview output (the default value for `-Z dump-mir-spanview` is "statement")
 // compile-flags: -Z dump-mir-spanview
 
-// EMIT_MIR spanview_statement.main.mir_map.0.html
+// EMIT_MIR spanview_statement.main.built.after.html
 fn main() {}
diff --git a/src/test/mir-opt/spanview_terminator.main.mir_map.0.html b/src/test/mir-opt/spanview_terminator.main.built.after.html
similarity index 95%
rename from src/test/mir-opt/spanview_terminator.main.mir_map.0.html
rename to src/test/mir-opt/spanview_terminator.main.built.after.html
index 55fafd90b0aa..aa7e44c15716 100644
--- a/src/test/mir-opt/spanview_terminator.main.mir_map.0.html
+++ b/src/test/mir-opt/spanview_terminator.main.built.after.html
@@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html>
 <head>
-<title>spanview_terminator.main.mir_map.0</title>
+<title>spanview_terminator.main.built.after</title>
 <style>
     .line {
         counter-increment: line;
@@ -59,7 +59,7 @@
 </style>
 </head>
 <body>
-<div class="code" style="counter-reset: line 4"><span class="line"><span class="code" style="--layer: 0">fn main() {}</span><span><span class="code even" style="--layer: 1" title="0:Return: $DIR/spanview-terminator.rs:5:13: 5:13:
+<div class="code" style="counter-reset: line 4"><span class="line"><span class="code" style="--layer: 0">fn main() {}</span><span><span class="code even" style="--layer: 1" title="0:Return: $DIR/spanview_terminator.rs:5:13: 5:13:
     5:13-5:13: Return: return"><span class="annotation">0:Return⦊</span>‸<span class="annotation">⦉0:Return</span></span></span></span></div>
 </body>
 </html>
diff --git a/src/test/mir-opt/spanview-terminator.rs b/src/test/mir-opt/spanview_terminator.rs
similarity index 64%
rename from src/test/mir-opt/spanview-terminator.rs
rename to src/test/mir-opt/spanview_terminator.rs
index 92e1411eadbd..76fced188f1d 100644
--- a/src/test/mir-opt/spanview-terminator.rs
+++ b/src/test/mir-opt/spanview_terminator.rs
@@ -1,5 +1,5 @@
 // Test spanview terminator output
 // compile-flags: -Z dump-mir-spanview=terminator
 
-// EMIT_MIR spanview_terminator.main.mir_map.0.html
+// EMIT_MIR spanview_terminator.main.built.after.html
 fn main() {}
diff --git a/src/test/mir-opt/tls_access.main.PreCodegen.after.mir b/src/test/mir-opt/tls_access.main.PreCodegen.after.mir
index b6c36be2bbe4..09453b8ba9c3 100644
--- a/src/test/mir-opt/tls_access.main.PreCodegen.after.mir
+++ b/src/test/mir-opt/tls_access.main.PreCodegen.after.mir
@@ -1,28 +1,28 @@
 // MIR for `main` after PreCodegen
 
 fn main() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/tls-access.rs:+0:11: +0:11
-    let _2: *mut u8;                     // in scope 0 at $DIR/tls-access.rs:+2:18: +2:21
-    let mut _3: *mut u8;                 // in scope 0 at $DIR/tls-access.rs:+3:9: +3:12
+    let mut _0: ();                      // return place in scope 0 at $DIR/tls_access.rs:+0:11: +0:11
+    let _2: *mut u8;                     // in scope 0 at $DIR/tls_access.rs:+2:18: +2:21
+    let mut _3: *mut u8;                 // in scope 0 at $DIR/tls_access.rs:+3:9: +3:12
     scope 1 {
-        let _1: &u8;                     // in scope 1 at $DIR/tls-access.rs:+2:13: +2:14
+        let _1: &u8;                     // in scope 1 at $DIR/tls_access.rs:+2:13: +2:14
         scope 2 {
-            debug a => _1;               // in scope 2 at $DIR/tls-access.rs:+2:13: +2:14
+            debug a => _1;               // in scope 2 at $DIR/tls_access.rs:+2:13: +2:14
         }
     }
 
     bb0: {
-        StorageLive(_1);                 // scope 1 at $DIR/tls-access.rs:+2:13: +2:14
-        StorageLive(_2);                 // scope 1 at $DIR/tls-access.rs:+2:18: +2:21
-        _2 = &/*tls*/ mut FOO;           // scope 1 at $DIR/tls-access.rs:+2:18: +2:21
-        _1 = &(*_2);                     // scope 1 at $DIR/tls-access.rs:+2:17: +2:21
-        StorageLive(_3);                 // scope 2 at $DIR/tls-access.rs:+3:9: +3:12
-        _3 = &/*tls*/ mut FOO;           // scope 2 at $DIR/tls-access.rs:+3:9: +3:12
-        (*_3) = const 42_u8;             // scope 2 at $DIR/tls-access.rs:+3:9: +3:17
-        StorageDead(_3);                 // scope 2 at $DIR/tls-access.rs:+3:17: +3:18
-        _0 = const ();                   // scope 1 at $DIR/tls-access.rs:+1:5: +4:6
-        StorageDead(_2);                 // scope 1 at $DIR/tls-access.rs:+4:5: +4:6
-        StorageDead(_1);                 // scope 1 at $DIR/tls-access.rs:+4:5: +4:6
-        return;                          // scope 0 at $DIR/tls-access.rs:+5:2: +5:2
+        StorageLive(_1);                 // scope 1 at $DIR/tls_access.rs:+2:13: +2:14
+        StorageLive(_2);                 // scope 1 at $DIR/tls_access.rs:+2:18: +2:21
+        _2 = &/*tls*/ mut FOO;           // scope 1 at $DIR/tls_access.rs:+2:18: +2:21
+        _1 = &(*_2);                     // scope 1 at $DIR/tls_access.rs:+2:17: +2:21
+        StorageLive(_3);                 // scope 2 at $DIR/tls_access.rs:+3:9: +3:12
+        _3 = &/*tls*/ mut FOO;           // scope 2 at $DIR/tls_access.rs:+3:9: +3:12
+        (*_3) = const 42_u8;             // scope 2 at $DIR/tls_access.rs:+3:9: +3:17
+        StorageDead(_3);                 // scope 2 at $DIR/tls_access.rs:+3:17: +3:18
+        _0 = const ();                   // scope 1 at $DIR/tls_access.rs:+1:5: +4:6
+        StorageDead(_2);                 // scope 1 at $DIR/tls_access.rs:+4:5: +4:6
+        StorageDead(_1);                 // scope 1 at $DIR/tls_access.rs:+4:5: +4:6
+        return;                          // scope 0 at $DIR/tls_access.rs:+5:2: +5:2
     }
 }
diff --git a/src/test/mir-opt/tls-access.rs b/src/test/mir-opt/tls_access.rs
similarity index 100%
rename from src/test/mir-opt/tls-access.rs
rename to src/test/mir-opt/tls_access.rs
diff --git a/src/test/mir-opt/uninhabited_enum.process_never.SimplifyLocals.after.mir b/src/test/mir-opt/uninhabited_enum.process_never.SimplifyLocals.after.mir
index 6ed53643f4bf..2c0fcc6621a3 100644
--- a/src/test/mir-opt/uninhabited_enum.process_never.SimplifyLocals.after.mir
+++ b/src/test/mir-opt/uninhabited_enum.process_never.SimplifyLocals.after.mir
@@ -1,16 +1,16 @@
 // MIR for `process_never` after SimplifyLocals
 
 fn process_never(_1: *const !) -> () {
-    debug input => _1;                   // in scope 0 at $DIR/uninhabited-enum.rs:+0:22: +0:27
-    let mut _0: ();                      // return place in scope 0 at $DIR/uninhabited-enum.rs:+0:39: +0:39
-    let _2: &!;                          // in scope 0 at $DIR/uninhabited-enum.rs:+1:8: +1:14
+    debug input => _1;                   // in scope 0 at $DIR/uninhabited_enum.rs:+0:22: +0:27
+    let mut _0: ();                      // return place in scope 0 at $DIR/uninhabited_enum.rs:+0:39: +0:39
+    let _2: &!;                          // in scope 0 at $DIR/uninhabited_enum.rs:+1:8: +1:14
     scope 1 {
-        debug _input => _2;              // in scope 1 at $DIR/uninhabited-enum.rs:+1:8: +1:14
+        debug _input => _2;              // in scope 1 at $DIR/uninhabited_enum.rs:+1:8: +1:14
     }
     scope 2 {
     }
 
     bb0: {
-        unreachable;                     // scope 0 at $DIR/uninhabited-enum.rs:+0:39: +2:2
+        unreachable;                     // scope 0 at $DIR/uninhabited_enum.rs:+0:39: +2:2
     }
 }
diff --git a/src/test/mir-opt/uninhabited_enum.process_void.SimplifyLocals.after.mir b/src/test/mir-opt/uninhabited_enum.process_void.SimplifyLocals.after.mir
index bbb81724ccfd..ae341a7b97b6 100644
--- a/src/test/mir-opt/uninhabited_enum.process_void.SimplifyLocals.after.mir
+++ b/src/test/mir-opt/uninhabited_enum.process_void.SimplifyLocals.after.mir
@@ -1,18 +1,18 @@
 // MIR for `process_void` after SimplifyLocals
 
 fn process_void(_1: *const Void) -> () {
-    debug input => _1;                   // in scope 0 at $DIR/uninhabited-enum.rs:+0:21: +0:26
-    let mut _0: ();                      // return place in scope 0 at $DIR/uninhabited-enum.rs:+0:41: +0:41
-    let _2: &Void;                       // in scope 0 at $DIR/uninhabited-enum.rs:+1:8: +1:14
+    debug input => _1;                   // in scope 0 at $DIR/uninhabited_enum.rs:+0:21: +0:26
+    let mut _0: ();                      // return place in scope 0 at $DIR/uninhabited_enum.rs:+0:41: +0:41
+    let _2: &Void;                       // in scope 0 at $DIR/uninhabited_enum.rs:+1:8: +1:14
     scope 1 {
-        debug _input => _2;              // in scope 1 at $DIR/uninhabited-enum.rs:+1:8: +1:14
+        debug _input => _2;              // in scope 1 at $DIR/uninhabited_enum.rs:+1:8: +1:14
     }
     scope 2 {
     }
 
     bb0: {
-        StorageLive(_2);                 // scope 0 at $DIR/uninhabited-enum.rs:+1:8: +1:14
-        StorageDead(_2);                 // scope 0 at $DIR/uninhabited-enum.rs:+4:1: +4:2
-        return;                          // scope 0 at $DIR/uninhabited-enum.rs:+4:2: +4:2
+        StorageLive(_2);                 // scope 0 at $DIR/uninhabited_enum.rs:+1:8: +1:14
+        StorageDead(_2);                 // scope 0 at $DIR/uninhabited_enum.rs:+4:1: +4:2
+        return;                          // scope 0 at $DIR/uninhabited_enum.rs:+4:2: +4:2
     }
 }
diff --git a/src/test/mir-opt/uninhabited-enum.rs b/src/test/mir-opt/uninhabited_enum.rs
similarity index 100%
rename from src/test/mir-opt/uninhabited-enum.rs
rename to src/test/mir-opt/uninhabited_enum.rs
diff --git a/src/test/mir-opt/unusual_item_types.E-V-{constant#0}.mir_map.0.mir b/src/test/mir-opt/unusual_item_types.E-V-{constant#0}.built.after.mir
similarity index 61%
rename from src/test/mir-opt/unusual_item_types.E-V-{constant#0}.mir_map.0.mir
rename to src/test/mir-opt/unusual_item_types.E-V-{constant#0}.built.after.mir
index a72e00ecde75..5257491f0d49 100644
--- a/src/test/mir-opt/unusual_item_types.E-V-{constant#0}.mir_map.0.mir
+++ b/src/test/mir-opt/unusual_item_types.E-V-{constant#0}.built.after.mir
@@ -1,10 +1,10 @@
-// MIR for `E::V::{constant#0}` 0 mir_map
+// MIR for `E::V::{constant#0}` after built
 
 E::V::{constant#0}: isize = {
-    let mut _0: isize;                   // return place in scope 0 at $DIR/unusual-item-types.rs:+0:9: +0:10
+    let mut _0: isize;                   // return place in scope 0 at $DIR/unusual_item_types.rs:+0:9: +0:10
 
     bb0: {
-        _0 = const 5_isize;              // scope 0 at $DIR/unusual-item-types.rs:+0:9: +0:10
-        return;                          // scope 0 at $DIR/unusual-item-types.rs:+0:9: +0:10
+        _0 = const 5_isize;              // scope 0 at $DIR/unusual_item_types.rs:+0:9: +0:10
+        return;                          // scope 0 at $DIR/unusual_item_types.rs:+0:9: +0:10
     }
 }
diff --git a/src/test/mir-opt/unusual_item_types.Test-X-{constructor#0}.mir_map.0.mir b/src/test/mir-opt/unusual_item_types.Test-X-{constructor#0}.built.after.mir
similarity index 65%
rename from src/test/mir-opt/unusual_item_types.Test-X-{constructor#0}.mir_map.0.mir
rename to src/test/mir-opt/unusual_item_types.Test-X-{constructor#0}.built.after.mir
index 0686af46ed58..ee029676311b 100644
--- a/src/test/mir-opt/unusual_item_types.Test-X-{constructor#0}.mir_map.0.mir
+++ b/src/test/mir-opt/unusual_item_types.Test-X-{constructor#0}.built.after.mir
@@ -1,12 +1,12 @@
-// MIR for `Test::X` 0 mir_map
+// MIR for `Test::X` after built
 
 fn Test::X(_1: usize) -> Test {
-    let mut _0: Test;                    // return place in scope 0 at $DIR/unusual-item-types.rs:+0:5: +0:6
+    let mut _0: Test;                    // return place in scope 0 at $DIR/unusual_item_types.rs:+0:5: +0:6
 
     bb0: {
-        Deinit(_0);                      // scope 0 at $DIR/unusual-item-types.rs:+0:5: +0:6
-        ((_0 as X).0: usize) = move _1;  // scope 0 at $DIR/unusual-item-types.rs:+0:5: +0:6
-        discriminant(_0) = 0;            // scope 0 at $DIR/unusual-item-types.rs:+0:5: +0:6
-        return;                          // scope 0 at $DIR/unusual-item-types.rs:+0:5: +0:6
+        Deinit(_0);                      // scope 0 at $DIR/unusual_item_types.rs:+0:5: +0:6
+        ((_0 as X).0: usize) = move _1;  // scope 0 at $DIR/unusual_item_types.rs:+0:5: +0:6
+        discriminant(_0) = 0;            // scope 0 at $DIR/unusual_item_types.rs:+0:5: +0:6
+        return;                          // scope 0 at $DIR/unusual_item_types.rs:+0:5: +0:6
     }
 }
diff --git a/src/test/mir-opt/unusual-item-types.rs b/src/test/mir-opt/unusual_item_types.rs
similarity index 69%
rename from src/test/mir-opt/unusual-item-types.rs
rename to src/test/mir-opt/unusual_item_types.rs
index 9ef3d86472db..6dad636416f2 100644
--- a/src/test/mir-opt/unusual-item-types.rs
+++ b/src/test/mir-opt/unusual_item_types.rs
@@ -5,19 +5,19 @@
 
 struct A;
 
-// EMIT_MIR unusual_item_types.{impl#0}-ASSOCIATED_CONSTANT.mir_map.0.mir
+// EMIT_MIR unusual_item_types.{impl#0}-ASSOCIATED_CONSTANT.built.after.mir
 impl A {
     const ASSOCIATED_CONSTANT: i32 = 2;
 }
 
 // See #59021
-// EMIT_MIR unusual_item_types.Test-X-{constructor#0}.mir_map.0.mir
+// EMIT_MIR unusual_item_types.Test-X-{constructor#0}.built.after.mir
 enum Test {
     X(usize),
     Y { a: usize },
 }
 
-// EMIT_MIR unusual_item_types.E-V-{constant#0}.mir_map.0.mir
+// EMIT_MIR unusual_item_types.E-V-{constant#0}.built.after.mir
 enum E {
     V = 5,
 }
diff --git a/src/test/mir-opt/unusual_item_types.{impl#0}-ASSOCIATED_CONSTANT.built.after.mir b/src/test/mir-opt/unusual_item_types.{impl#0}-ASSOCIATED_CONSTANT.built.after.mir
new file mode 100644
index 000000000000..90444b481221
--- /dev/null
+++ b/src/test/mir-opt/unusual_item_types.{impl#0}-ASSOCIATED_CONSTANT.built.after.mir
@@ -0,0 +1,10 @@
+// MIR for `<impl at $DIR/unusual_item_types.rs:9:1: 9:7>::ASSOCIATED_CONSTANT` after built
+
+const <impl at $DIR/unusual_item_types.rs:9:1: 9:7>::ASSOCIATED_CONSTANT: i32 = {
+    let mut _0: i32;                     // return place in scope 0 at $DIR/unusual_item_types.rs:+0:32: +0:35
+
+    bb0: {
+        _0 = const 2_i32;                // scope 0 at $DIR/unusual_item_types.rs:+0:38: +0:39
+        return;                          // scope 0 at $DIR/unusual_item_types.rs:+0:5: +0:40
+    }
+}
diff --git a/src/test/mir-opt/unusual_item_types.{impl#0}-ASSOCIATED_CONSTANT.mir_map.0.mir b/src/test/mir-opt/unusual_item_types.{impl#0}-ASSOCIATED_CONSTANT.mir_map.0.mir
deleted file mode 100644
index 5579d25a14fd..000000000000
--- a/src/test/mir-opt/unusual_item_types.{impl#0}-ASSOCIATED_CONSTANT.mir_map.0.mir
+++ /dev/null
@@ -1,10 +0,0 @@
-// MIR for `<impl at $DIR/unusual-item-types.rs:9:1: 9:7>::ASSOCIATED_CONSTANT` 0 mir_map
-
-const <impl at $DIR/unusual-item-types.rs:9:1: 9:7>::ASSOCIATED_CONSTANT: i32 = {
-    let mut _0: i32;                     // return place in scope 0 at $DIR/unusual-item-types.rs:+0:32: +0:35
-
-    bb0: {
-        _0 = const 2_i32;                // scope 0 at $DIR/unusual-item-types.rs:+0:38: +0:39
-        return;                          // scope 0 at $DIR/unusual-item-types.rs:+0:5: +0:40
-    }
-}
diff --git a/src/test/mir-opt/while-storage.rs b/src/test/mir-opt/while_storage.rs
similarity index 100%
rename from src/test/mir-opt/while-storage.rs
rename to src/test/mir-opt/while_storage.rs
diff --git a/src/test/mir-opt/while_storage.while_loop.PreCodegen.after.mir b/src/test/mir-opt/while_storage.while_loop.PreCodegen.after.mir
index a5e7d6afdf36..68aa3e5db329 100644
--- a/src/test/mir-opt/while_storage.while_loop.PreCodegen.after.mir
+++ b/src/test/mir-opt/while_storage.while_loop.PreCodegen.after.mir
@@ -1,56 +1,56 @@
 // MIR for `while_loop` after PreCodegen
 
 fn while_loop(_1: bool) -> () {
-    debug c => _1;                       // in scope 0 at $DIR/while-storage.rs:+0:15: +0:16
-    let mut _0: ();                      // return place in scope 0 at $DIR/while-storage.rs:+0:24: +0:24
-    let mut _2: bool;                    // in scope 0 at $DIR/while-storage.rs:+1:11: +1:22
-    let mut _3: bool;                    // in scope 0 at $DIR/while-storage.rs:+1:20: +1:21
-    let mut _4: bool;                    // in scope 0 at $DIR/while-storage.rs:+2:12: +2:23
-    let mut _5: bool;                    // in scope 0 at $DIR/while-storage.rs:+2:21: +2:22
+    debug c => _1;                       // in scope 0 at $DIR/while_storage.rs:+0:15: +0:16
+    let mut _0: ();                      // return place in scope 0 at $DIR/while_storage.rs:+0:24: +0:24
+    let mut _2: bool;                    // in scope 0 at $DIR/while_storage.rs:+1:11: +1:22
+    let mut _3: bool;                    // in scope 0 at $DIR/while_storage.rs:+1:20: +1:21
+    let mut _4: bool;                    // in scope 0 at $DIR/while_storage.rs:+2:12: +2:23
+    let mut _5: bool;                    // in scope 0 at $DIR/while_storage.rs:+2:21: +2:22
 
     bb0: {
-        goto -> bb1;                     // scope 0 at $DIR/while-storage.rs:+1:5: +5:6
+        goto -> bb1;                     // scope 0 at $DIR/while_storage.rs:+1:5: +5:6
     }
 
     bb1: {
-        StorageLive(_2);                 // scope 0 at $DIR/while-storage.rs:+1:11: +1:22
-        StorageLive(_3);                 // scope 0 at $DIR/while-storage.rs:+1:20: +1:21
-        _3 = _1;                         // scope 0 at $DIR/while-storage.rs:+1:20: +1:21
-        _2 = get_bool(move _3) -> bb2;   // scope 0 at $DIR/while-storage.rs:+1:11: +1:22
+        StorageLive(_2);                 // scope 0 at $DIR/while_storage.rs:+1:11: +1:22
+        StorageLive(_3);                 // scope 0 at $DIR/while_storage.rs:+1:20: +1:21
+        _3 = _1;                         // scope 0 at $DIR/while_storage.rs:+1:20: +1:21
+        _2 = get_bool(move _3) -> bb2;   // scope 0 at $DIR/while_storage.rs:+1:11: +1:22
                                          // mir::Constant
-                                         // + span: $DIR/while-storage.rs:10:11: 10:19
+                                         // + span: $DIR/while_storage.rs:10:11: 10:19
                                          // + literal: Const { ty: fn(bool) -> bool {get_bool}, val: Value(<ZST>) }
     }
 
     bb2: {
-        StorageDead(_3);                 // scope 0 at $DIR/while-storage.rs:+1:21: +1:22
-        switchInt(move _2) -> [false: bb7, otherwise: bb3]; // scope 0 at $DIR/while-storage.rs:+1:11: +1:22
+        StorageDead(_3);                 // scope 0 at $DIR/while_storage.rs:+1:21: +1:22
+        switchInt(move _2) -> [false: bb7, otherwise: bb3]; // scope 0 at $DIR/while_storage.rs:+1:11: +1:22
     }
 
     bb3: {
-        StorageLive(_4);                 // scope 0 at $DIR/while-storage.rs:+2:12: +2:23
-        StorageLive(_5);                 // scope 0 at $DIR/while-storage.rs:+2:21: +2:22
-        _5 = _1;                         // scope 0 at $DIR/while-storage.rs:+2:21: +2:22
-        _4 = get_bool(move _5) -> bb4;   // scope 0 at $DIR/while-storage.rs:+2:12: +2:23
+        StorageLive(_4);                 // scope 0 at $DIR/while_storage.rs:+2:12: +2:23
+        StorageLive(_5);                 // scope 0 at $DIR/while_storage.rs:+2:21: +2:22
+        _5 = _1;                         // scope 0 at $DIR/while_storage.rs:+2:21: +2:22
+        _4 = get_bool(move _5) -> bb4;   // scope 0 at $DIR/while_storage.rs:+2:12: +2:23
                                          // mir::Constant
-                                         // + span: $DIR/while-storage.rs:11:12: 11:20
+                                         // + span: $DIR/while_storage.rs:11:12: 11:20
                                          // + literal: Const { ty: fn(bool) -> bool {get_bool}, val: Value(<ZST>) }
     }
 
     bb4: {
-        StorageDead(_5);                 // scope 0 at $DIR/while-storage.rs:+2:22: +2:23
-        switchInt(move _4) -> [false: bb6, otherwise: bb5]; // scope 0 at $DIR/while-storage.rs:+2:12: +2:23
+        StorageDead(_5);                 // scope 0 at $DIR/while_storage.rs:+2:22: +2:23
+        switchInt(move _4) -> [false: bb6, otherwise: bb5]; // scope 0 at $DIR/while_storage.rs:+2:12: +2:23
     }
 
     bb5: {
-        StorageDead(_4);                 // scope 0 at $DIR/while-storage.rs:+4:9: +4:10
+        StorageDead(_4);                 // scope 0 at $DIR/while_storage.rs:+4:9: +4:10
         goto -> bb8;                     // scope 0 at no-location
     }
 
     bb6: {
-        StorageDead(_4);                 // scope 0 at $DIR/while-storage.rs:+4:9: +4:10
-        StorageDead(_2);                 // scope 0 at $DIR/while-storage.rs:+5:5: +5:6
-        goto -> bb1;                     // scope 0 at $DIR/while-storage.rs:+1:5: +5:6
+        StorageDead(_4);                 // scope 0 at $DIR/while_storage.rs:+4:9: +4:10
+        StorageDead(_2);                 // scope 0 at $DIR/while_storage.rs:+5:5: +5:6
+        goto -> bb1;                     // scope 0 at $DIR/while_storage.rs:+1:5: +5:6
     }
 
     bb7: {
@@ -58,7 +58,7 @@ fn while_loop(_1: bool) -> () {
     }
 
     bb8: {
-        StorageDead(_2);                 // scope 0 at $DIR/while-storage.rs:+5:5: +5:6
-        return;                          // scope 0 at $DIR/while-storage.rs:+6:2: +6:2
+        StorageDead(_2);                 // scope 0 at $DIR/while_storage.rs:+5:5: +5:6
+        return;                          // scope 0 at $DIR/while_storage.rs:+6:2: +6:2
     }
 }
diff --git a/src/test/run-make-fulldeps/foreign-rust-exceptions/Makefile b/src/test/run-make-fulldeps/foreign-rust-exceptions/Makefile
new file mode 100644
index 000000000000..50fca7f24e61
--- /dev/null
+++ b/src/test/run-make-fulldeps/foreign-rust-exceptions/Makefile
@@ -0,0 +1,11 @@
+# ignore-i686-pc-windows-gnu
+
+# This test doesn't work on 32-bit MinGW as cdylib has its own copy of unwinder
+# so cross-DLL unwinding does not work.
+
+include ../tools.mk
+
+all:
+	$(RUSTC) bar.rs --crate-type=cdylib
+	$(RUSTC) foo.rs
+	$(call RUN,foo) 2>&1 | $(CGREP) "Rust cannot catch foreign exceptions"
diff --git a/src/test/run-make-fulldeps/foreign-rust-exceptions/bar.rs b/src/test/run-make-fulldeps/foreign-rust-exceptions/bar.rs
new file mode 100644
index 000000000000..5f9efe323609
--- /dev/null
+++ b/src/test/run-make-fulldeps/foreign-rust-exceptions/bar.rs
@@ -0,0 +1,7 @@
+#![crate_type = "cdylib"]
+#![feature(c_unwind)]
+
+#[no_mangle]
+extern "C-unwind" fn panic() {
+    panic!();
+}
diff --git a/src/test/run-make-fulldeps/foreign-rust-exceptions/foo.rs b/src/test/run-make-fulldeps/foreign-rust-exceptions/foo.rs
new file mode 100644
index 000000000000..266987c5b6d6
--- /dev/null
+++ b/src/test/run-make-fulldeps/foreign-rust-exceptions/foo.rs
@@ -0,0 +1,13 @@
+#![feature(c_unwind)]
+
+#[cfg_attr(not(windows), link(name = "bar"))]
+#[cfg_attr(windows, link(name = "bar.dll"))]
+extern "C-unwind" {
+    fn panic();
+}
+
+fn main() {
+    let _ = std::panic::catch_unwind(|| {
+        unsafe { panic() };
+    });
+}
diff --git a/src/test/run-make-fulldeps/issue-51671/Makefile b/src/test/run-make-fulldeps/issue-51671/Makefile
index 1d1d370d3826..c93645369928 100644
--- a/src/test/run-make-fulldeps/issue-51671/Makefile
+++ b/src/test/run-make-fulldeps/issue-51671/Makefile
@@ -6,4 +6,4 @@ all:
 	$(RUSTC) --emit=obj app.rs
 	nm $(TMPDIR)/app.o | $(CGREP) rust_begin_unwind
 	nm $(TMPDIR)/app.o | $(CGREP) rust_eh_personality
-	nm $(TMPDIR)/app.o | $(CGREP) rust_oom
+	nm $(TMPDIR)/app.o | $(CGREP) __rg_oom
diff --git a/src/test/run-make-fulldeps/issue-51671/app.rs b/src/test/run-make-fulldeps/issue-51671/app.rs
index c13937dcfbe5..e9dc1e9744fb 100644
--- a/src/test/run-make-fulldeps/issue-51671/app.rs
+++ b/src/test/run-make-fulldeps/issue-51671/app.rs
@@ -1,5 +1,5 @@
 #![crate_type = "bin"]
-#![feature(lang_items)]
+#![feature(lang_items, alloc_error_handler)]
 #![no_main]
 #![no_std]
 
@@ -14,7 +14,7 @@ fn panic(_: &PanicInfo) -> ! {
 #[lang = "eh_personality"]
 fn eh() {}
 
-#[lang = "oom"]
+#[alloc_error_handler]
 fn oom(_: Layout) -> ! {
     loop {}
 }
diff --git a/src/test/run-make-fulldeps/libtest-json/output-default.json b/src/test/run-make-fulldeps/libtest-json/output-default.json
index 63342abc6ef7..ad22b66eda69 100644
--- a/src/test/run-make-fulldeps/libtest-json/output-default.json
+++ b/src/test/run-make-fulldeps/libtest-json/output-default.json
@@ -2,7 +2,7 @@
 { "type": "test", "event": "started", "name": "a" }
 { "type": "test", "name": "a", "event": "ok" }
 { "type": "test", "event": "started", "name": "b" }
-{ "type": "test", "name": "b", "event": "failed", "stdout": "thread 'main' panicked at 'assertion failed: false', f.rs:9:5\nnote: run with `RUST_BACKTRACE=1` environment variable to display a backtrace\n" }
+{ "type": "test", "name": "b", "event": "failed", "stdout": "thread 'b' panicked at 'assertion failed: false', f.rs:9:5\nnote: run with `RUST_BACKTRACE=1` environment variable to display a backtrace\n" }
 { "type": "test", "event": "started", "name": "c" }
 { "type": "test", "name": "c", "event": "ok" }
 { "type": "test", "event": "started", "name": "d" }
diff --git a/src/test/run-make-fulldeps/libtest-json/output-stdout-success.json b/src/test/run-make-fulldeps/libtest-json/output-stdout-success.json
index 8f19114460e8..ec98172eb1c4 100644
--- a/src/test/run-make-fulldeps/libtest-json/output-stdout-success.json
+++ b/src/test/run-make-fulldeps/libtest-json/output-stdout-success.json
@@ -2,9 +2,9 @@
 { "type": "test", "event": "started", "name": "a" }
 { "type": "test", "name": "a", "event": "ok", "stdout": "print from successful test\n" }
 { "type": "test", "event": "started", "name": "b" }
-{ "type": "test", "name": "b", "event": "failed", "stdout": "thread 'main' panicked at 'assertion failed: false', f.rs:9:5\nnote: run with `RUST_BACKTRACE=1` environment variable to display a backtrace\n" }
+{ "type": "test", "name": "b", "event": "failed", "stdout": "thread 'b' panicked at 'assertion failed: false', f.rs:9:5\nnote: run with `RUST_BACKTRACE=1` environment variable to display a backtrace\n" }
 { "type": "test", "event": "started", "name": "c" }
-{ "type": "test", "name": "c", "event": "ok", "stdout": "thread 'main' panicked at 'assertion failed: false', f.rs:15:5\n" }
+{ "type": "test", "name": "c", "event": "ok", "stdout": "thread 'c' panicked at 'assertion failed: false', f.rs:15:5\n" }
 { "type": "test", "event": "started", "name": "d" }
 { "type": "test", "name": "d", "event": "ignored", "message": "msg" }
 { "type": "suite", "event": "failed", "passed": 2, "failed": 1, "ignored": 1, "measured": 0, "filtered_out": 0, "exec_time": $TIME }
diff --git a/src/test/run-make-fulldeps/link-dedup/Makefile b/src/test/run-make-fulldeps/link-dedup/Makefile
index 5c9603352989..eff18ab48ab4 100644
--- a/src/test/run-make-fulldeps/link-dedup/Makefile
+++ b/src/test/run-make-fulldeps/link-dedup/Makefile
@@ -9,4 +9,4 @@ all:
 	$(RUSTC) empty.rs --cfg bar 2>&1 | $(CGREP) '"-ltesta" "-ltestb" "-ltesta"'
 	$(RUSTC) empty.rs 2>&1 | $(CGREP) '"-ltesta"'
 	$(RUSTC) empty.rs 2>&1 | $(CGREP) -v '"-ltestb"'
-	$(RUSTC) empty.rs 2>&1 | $(CGREP) -v '"-ltesta" "-ltesta"'
+	$(RUSTC) empty.rs 2>&1 | $(CGREP) -v '"-ltesta" "-ltesta" "-ltesta"'
diff --git a/src/test/run-make-fulldeps/link-dedup/depa.rs b/src/test/run-make-fulldeps/link-dedup/depa.rs
index e48ffd6413cd..19178c5bd495 100644
--- a/src/test/run-make-fulldeps/link-dedup/depa.rs
+++ b/src/test/run-make-fulldeps/link-dedup/depa.rs
@@ -5,3 +5,6 @@ extern "C" {}
 
 #[link(name = "testa")]
 extern "C" {}
+
+#[link(name = "testa")]
+extern "C" {}
diff --git a/src/test/run-make-fulldeps/obtain-borrowck/driver.rs b/src/test/run-make-fulldeps/obtain-borrowck/driver.rs
index 8f78bda033ec..a6c60df83a63 100644
--- a/src/test/run-make-fulldeps/obtain-borrowck/driver.rs
+++ b/src/test/run-make-fulldeps/obtain-borrowck/driver.rs
@@ -69,25 +69,25 @@ impl rustc_driver::Callbacks for CompilerCalls {
 
             let crate_items = tcx.hir_crate_items(());
             for id in crate_items.items() {
-                if matches!(tcx.def_kind(id.def_id), DefKind::Fn) {
-                    bodies.push(id.def_id);
+                if matches!(tcx.def_kind(id.owner_id), DefKind::Fn) {
+                    bodies.push(id.owner_id);
                 }
             }
 
             for id in crate_items.trait_items() {
-                if matches!(tcx.def_kind(id.def_id), DefKind::AssocFn) {
+                if matches!(tcx.def_kind(id.owner_id), DefKind::AssocFn) {
                     let trait_item = hir.trait_item(id);
                     if let rustc_hir::TraitItemKind::Fn(_, trait_fn) = &trait_item.kind {
                         if let rustc_hir::TraitFn::Provided(_) = trait_fn {
-                            bodies.push(trait_item.def_id);
+                            bodies.push(trait_item.owner_id);
                         }
                     }
                 }
             }
 
             for id in crate_items.impl_items() {
-                if matches!(tcx.def_kind(id.def_id), DefKind::AssocFn) {
-                    bodies.push(id.def_id);
+                if matches!(tcx.def_kind(id.owner_id), DefKind::AssocFn) {
+                    bodies.push(id.owner_id);
                 }
             }
 
diff --git a/src/test/run-make-fulldeps/split-debuginfo/Makefile b/src/test/run-make-fulldeps/split-debuginfo/Makefile
index 1032f3408f06..1831ab38fab4 100644
--- a/src/test/run-make-fulldeps/split-debuginfo/Makefile
+++ b/src/test/run-make-fulldeps/split-debuginfo/Makefile
@@ -3,7 +3,7 @@ include ../tools.mk
 all: off packed unpacked
 
 ifeq ($(UNAME),Darwin)
-# If disabled, don't run dsymutil
+# If disabled, don't run `dsymutil`.
 off:
 	rm -rf $(TMPDIR)/*.dSYM
 	$(RUSTC) foo.rs -g -C split-debuginfo=off
@@ -29,98 +29,280 @@ unpacked:
 	[ ! -d $(TMPDIR)/foo.dSYM ]
 else
 ifdef IS_WINDOWS
-# Windows only supports =packed
+# Windows only supports packed debuginfo - nothing to test.
 off:
 packed:
 unpacked:
 else
+# Some non-Windows, non-Darwin platforms are not stable, and some are.
 ifeq ($(UNAME),Linux)
   UNSTABLEOPTS :=
 else
   UNSTABLEOPTS := -Zunstable-options
 endif
 
+# - Debuginfo in `.o` files
+# - `.o` deleted
+# - `.dwo` never created
+# - `.dwp` never created
 off:
 	$(RUSTC) foo.rs -g -C $(UNSTABLEOPTS) split-debuginfo=off
 	[ ! -f $(TMPDIR)/*.dwp ]
 	[ ! -f $(TMPDIR)/*.dwo ]
-
 	$(RUSTC) foo.rs -g
 	[ ! -f $(TMPDIR)/*.dwp ]
 	[ ! -f $(TMPDIR)/*.dwo ]
 
-packed: packed-split packed-single
+packed: packed-split packed-single packed-lto packed-remapped packed-crosscrate
 
+# - Debuginfo in `.dwo` files
+# - `.o` deleted
+# - `.dwo` deleted
+# - `.dwp` present
 packed-split:
 	$(RUSTC) foo.rs -g $(UNSTABLEOPTS) -C split-debuginfo=packed -Zsplit-dwarf-kind=split
-	ls $(TMPDIR)/*.dwp
-	rm -rf $(TMPDIR)/*.dwp $(TMPDIR)/*.dwo
+	ls $(TMPDIR)/*.o && exit 1 || exit 0
+	ls $(TMPDIR)/*.dwo && exit 1 || exit 0
+	rm $(TMPDIR)/foo.dwp
+	rm $(TMPDIR)/$(call BIN,foo)
 
+# - Debuginfo in `.o` files
+# - `.o` deleted
+# - `.dwo` never created
+# - `.dwp` present
 packed-single:
 	$(RUSTC) foo.rs -g $(UNSTABLEOPTS) -C split-debuginfo=packed -Zsplit-dwarf-kind=single
-	ls $(TMPDIR)/*.dwp
+	ls $(TMPDIR)/*.o && exit 1 || exit 0
 	ls $(TMPDIR)/*.dwo && exit 1 || exit 0
-	rm -rf $(TMPDIR)/*.dwp
+	rm $(TMPDIR)/foo.dwp
+	rm $(TMPDIR)/$(call BIN,foo)
+
+packed-lto: packed-lto-split packed-lto-single
+
+# - rmeta file added to rlib, no object files are generated and thus no debuginfo is generated
+# - `.o` never created
+# - `.dwo` never created
+# - `.dwp` never created
+packed-lto-split:
+	$(RUSTC) baz.rs -g $(UNSTABLEOPTS) -Csplit-debuginfo=packed -Zsplit-dwarf-kind=split \
+		--crate-type=rlib -Clinker-plugin-lto
+	ls $(TMPDIR)/*.o && exit 1 || exit 0
+	ls $(TMPDIR)/*.dwo && exit 1 || exit 0
+	ls $(TMPDIR)/*.dwp && exit 1 || exit 0
+	rm $(TMPDIR)/libbaz.rlib
+
+# - rmeta file added to rlib, no object files are generated and thus no debuginfo is generated
+# - `.o` never created
+# - `.dwo` never created
+# - `.dwp` never created
+packed-lto-single:
+	$(RUSTC) baz.rs -g $(UNSTABLEOPTS) -Csplit-debuginfo=packed -Zsplit-dwarf-kind=single \
+		--crate-type=rlib -Clinker-plugin-lto
+	ls $(TMPDIR)/*.o && exit 1 || exit 0
+	ls $(TMPDIR)/*.dwo && exit 1 || exit 0
+	ls $(TMPDIR)/*.dwp && exit 1 || exit 0
+	rm $(TMPDIR)/libbaz.rlib
 
 packed-remapped: packed-remapped-split packed-remapped-single
 
+# - Debuginfo in `.dwo` files
+# - `.o` and binary refer to remapped `.dwo` paths which do not exist
+# - `.o` deleted
+# - `.dwo` deleted
+# - `.dwp` present
 packed-remapped-split:
 	$(RUSTC) $(UNSTABLEOPTS) -C split-debuginfo=packed -C debuginfo=2 \
 		-Z split-dwarf-kind=split --remap-path-prefix $(TMPDIR)=/a foo.rs -g
 	objdump -Wi $(TMPDIR)/foo | grep DW_AT_GNU_dwo_name | (! grep $(TMPDIR)) || exit 1
+	ls $(TMPDIR)/*.o && exit 1 || exit 0
+	ls $(TMPDIR)/*.dwo && exit 1 || exit 0
+	rm $(TMPDIR)/foo.dwp
+	rm $(TMPDIR)/$(call BIN,foo)
 
+# - Debuginfo in `.o` files
+# - `.o` and binary refer to remapped `.o` paths which do not exist
+# - `.o` deleted
+# - `.dwo` never created
+# - `.dwp` present
 packed-remapped-single:
 	$(RUSTC) $(UNSTABLEOPTS) -C split-debuginfo=packed -C debuginfo=2 \
 		-Z split-dwarf-kind=single --remap-path-prefix $(TMPDIR)=/a foo.rs -g
 	objdump -Wi $(TMPDIR)/foo | grep DW_AT_GNU_dwo_name | (! grep $(TMPDIR)) || exit 1
+	ls $(TMPDIR)/*.o && exit 1 || exit 0
+	ls $(TMPDIR)/*.dwo && exit 1 || exit 0
+	rm $(TMPDIR)/foo.dwp
+	rm $(TMPDIR)/$(call BIN,foo)
 
 packed-crosscrate: packed-crosscrate-split packed-crosscrate-single
 
+# - Debuginfo in `.dwo` files
+# - (bar) `.rlib` file created, contains `.dwo`
+# - (bar) `.o` deleted
+# - (bar) `.dwo` deleted
+# - (bar) `.dwp` never created
+# - (main) `.o` deleted
+# - (main) `.dwo` deleted
+# - (main) `.dwp` present
 packed-crosscrate-split:
 	$(RUSTC) --crate-type lib $(UNSTABLEOPTS) -C split-debuginfo=packed \
 		-Zsplit-dwarf-kind=split -C debuginfo=2 -g bar.rs
 	ls $(TMPDIR)/*.rlib
+	ls $(TMPDIR)/*.o && exit 1 || exit 0
 	ls $(TMPDIR)/*.dwo && exit 1 || exit 0
 	ls $(TMPDIR)/*.dwp && exit 1 || exit 0
-	$(RUSTC) --extern bar=$(TMPDIR)/libbar.rlib -Z unstable-options $(UNSTABLEOPTS) \
+	$(RUSTC) --extern bar=$(TMPDIR)/libbar.rlib $(UNSTABLEOPTS) \
 		-C split-debuginfo=packed -Zsplit-dwarf-kind=split -C debuginfo=2 -g main.rs
-	rm $(TMPDIR)/*.dwo
+	ls $(TMPDIR)/*.o && exit 1 || exit 0
+	ls $(TMPDIR)/*.dwo && exit 1 || exit 0
 	rm $(TMPDIR)/main.dwp
 	rm $(TMPDIR)/$(call BIN,main)
 
+# - Debuginfo in `.o` files
+# - (bar) `.rlib` file created, contains `.o`
+# - (bar) `.o` deleted
+# - (bar) `.dwo` never created
+# - (bar) `.dwp` never created
+# - (main) `.o` deleted
+# - (main) `.dwo` never created
+# - (main) `.dwp` present
 packed-crosscrate-single:
 	$(RUSTC) --crate-type lib $(UNSTABLEOPTS) -C split-debuginfo=packed \
 		-Zsplit-dwarf-kind=single -C debuginfo=2 -g bar.rs
 	ls $(TMPDIR)/*.rlib
+	ls $(TMPDIR)/*.o && exit 1 || exit 0
 	ls $(TMPDIR)/*.dwo && exit 1 || exit 0
 	ls $(TMPDIR)/*.dwp && exit 1 || exit 0
-	$(RUSTC) --extern bar=$(TMPDIR)/libbar.rlib -Z unstable-options $(UNSTABLEOPTS) \
+	$(RUSTC) --extern bar=$(TMPDIR)/libbar.rlib $(UNSTABLEOPTS) \
 		-C split-debuginfo=packed -Zsplit-dwarf-kind=single -C debuginfo=2 -g main.rs
+	ls $(TMPDIR)/*.o && exit 1 || exit 0
 	ls $(TMPDIR)/*.dwo && exit 1 || exit 0
 	rm $(TMPDIR)/main.dwp
 	rm $(TMPDIR)/$(call BIN,main)
 
-unpacked: unpacked-split unpacked-single unpacked-remapped-split unpacked-remapped-single
+unpacked: unpacked-split unpacked-single unpacked-lto unpacked-remapped unpacked-crosscrate
 
+# - Debuginfo in `.dwo` files
+# - `.o` deleted
+# - `.dwo` present
+# - `.dwp` never created
 unpacked-split:
 	$(RUSTC) foo.rs -g $(UNSTABLEOPTS) -C split-debuginfo=unpacked -Zsplit-dwarf-kind=split
+	ls $(TMPDIR)/*.o && exit 1 || exit 0
+	rm $(TMPDIR)/*.dwo
 	ls $(TMPDIR)/*.dwp && exit 1 || exit 0
-	ls $(TMPDIR)/*.dwo
-	rm -rf $(TMPDIR)/*.dwp $(TMPDIR)/*.dwo
+	rm $(TMPDIR)/$(call BIN,foo)
 
+# - Debuginfo in `.o` files
+# - `.o` present
+# - `.dwo` never created
+# - `.dwp` never created
 unpacked-single:
 	$(RUSTC) foo.rs -g $(UNSTABLEOPTS) -C split-debuginfo=unpacked -Zsplit-dwarf-kind=single
-	ls $(TMPDIR)/*.dwp && exit 1 || exit 0
+	ls $(TMPDIR)/*.o
 	ls $(TMPDIR)/*.dwo && exit 1 || exit 0
+	ls $(TMPDIR)/*.dwp && exit 1 || exit 0
+	rm $(TMPDIR)/$(call BIN,foo)
 
+unpacked-lto: packed-lto-split packed-lto-single
+
+# - rmeta file added to rlib, no object files are generated and thus no debuginfo is generated
+# - `.o` never created
+# - `.dwo` never created
+# - `.dwp` never created
+unpacked-lto-split:
+	$(RUSTC) baz.rs -g $(UNSTABLEOPTS) -Csplit-debuginfo=unpacked -Zsplit-dwarf-kind=split \
+		--crate-type=rlib -Clinker-plugin-lto
+	ls $(TMPDIR)/*.o && exit 1 || exit 0
+	ls $(TMPDIR)/*.dwo && exit 1 || exit 0
+	ls $(TMPDIR)/*.dwp && exit 1 || exit 0
+	rm $(TMPDIR)/libbaz.rlib
+
+# - rmeta file added to rlib, no object files are generated and thus no debuginfo is generated
+# - `.o` never created
+# - `.dwo` never created
+# - `.dwp` never created
+unpacked-lto-single:
+	$(RUSTC) baz.rs -g $(UNSTABLEOPTS) -Csplit-debuginfo=unpacked -Zsplit-dwarf-kind=single \
+		--crate-type=rlib -Clinker-plugin-lto
+	ls $(TMPDIR)/*.o && exit 1 || exit 0
+	ls $(TMPDIR)/*.dwo && exit 1 || exit 0
+	ls $(TMPDIR)/*.dwp && exit 1 || exit 0
+	rm $(TMPDIR)/libbaz.rlib
+
+unpacked-remapped: unpacked-remapped-split unpacked-remapped-single
+
+# - Debuginfo in `.dwo` files
+# - `.o` and binary refer to remapped `.dwo` paths which do not exist
+# - `.o` deleted
+# - `.dwo` present
+# - `.dwp` never created
 unpacked-remapped-split:
 	$(RUSTC) $(UNSTABLEOPTS) -C split-debuginfo=unpacked -C debuginfo=2 \
 		-Z split-dwarf-kind=split --remap-path-prefix $(TMPDIR)=/a foo.rs -g
 	objdump -Wi $(TMPDIR)/foo | grep DW_AT_GNU_dwo_name | (! grep $(TMPDIR)) || exit 1
+	ls $(TMPDIR)/*.o && exit 1 || exit 0
+	rm $(TMPDIR)/*.dwo
+	ls $(TMPDIR)/*.dwp && exit 1 || exit 0
+	rm $(TMPDIR)/$(call BIN,foo)
 
+# - Debuginfo in `.o` files
+# - `.o` and binary refer to remapped `.o` paths which do not exist
+# - `.o` present
+# - `.dwo` never created
+# - `.dwp` never created
 unpacked-remapped-single:
 	$(RUSTC) $(UNSTABLEOPTS) -C split-debuginfo=unpacked -C debuginfo=2 \
 		-Z split-dwarf-kind=single --remap-path-prefix $(TMPDIR)=/a foo.rs -g
 	objdump -Wi $(TMPDIR)/foo | grep DW_AT_GNU_dwo_name | (! grep $(TMPDIR)) || exit 1
+	ls $(TMPDIR)/*.o
+	ls $(TMPDIR)/*.dwo && exit 1 || exit 0
+	ls $(TMPDIR)/*.dwp && exit 1 || exit 0
+	rm $(TMPDIR)/$(call BIN,foo)
+
+unpacked-crosscrate: packed-crosscrate-split packed-crosscrate-single
+
+# - Debuginfo in `.dwo` files
+# - (bar) `.rlib` file created, contains `.dwo`
+# - (bar) `.o` deleted
+# - (bar) `.dwo` present
+# - (bar) `.dwp` never created
+# - (main) `.o` deleted
+# - (main) `.dwo` present
+# - (main) `.dwp` never created
+unpacked-crosscrate-split:
+	$(RUSTC) --crate-type lib $(UNSTABLEOPTS) -C split-debuginfo=unpacked \
+		-Zsplit-dwarf-kind=split -C debuginfo=2 -g bar.rs
+	ls $(TMPDIR)/*.rlib
+	ls $(TMPDIR)/*.o && exit 1 || exit 0
+	ls $(TMPDIR)/*.dwo
+	ls $(TMPDIR)/*.dwp && exit 1 || exit 0
+	$(RUSTC) --extern bar=$(TMPDIR)/libbar.rlib $(UNSTABLEOPTS) \
+		-C split-debuginfo=unpacked -Zsplit-dwarf-kind=split -C debuginfo=2 -g main.rs
+	ls $(TMPDIR)/*.o && exit 1 || exit 0
+	rm $(TMPDIR)/*.dwo
+	ls $(TMPDIR)/*.dwp && exit 1 || exit 0
+	rm $(TMPDIR)/$(call BIN,main)
+
+# - Debuginfo in `.o` files
+# - (bar) `.rlib` file created, contains `.o`
+# - (bar) `.o` present
+# - (bar) `.dwo` never created
+# - (bar) `.dwp` never created
+# - (main) `.o` present
+# - (main) `.dwo` never created
+# - (main) `.dwp` never created
+unpacked-crosscrate-single:
+	$(RUSTC) --crate-type lib $(UNSTABLEOPTS) -C split-debuginfo=unpacked \
+		-Zsplit-dwarf-kind=single -C debuginfo=2 -g bar.rs
+	ls $(TMPDIR)/*.rlib
+	ls $(TMPDIR)/*.o
+	ls $(TMPDIR)/*.dwo && exit 1 || exit 0
+	ls $(TMPDIR)/*.dwp && exit 1 || exit 0
+	$(RUSTC) --extern bar=$(TMPDIR)/libbar.rlib $(UNSTABLEOPTS) \
+		-C split-debuginfo=unpacked -Zsplit-dwarf-kind=single -C debuginfo=2 -g main.rs
+	ls $(TMPDIR)/*.o
+	ls $(TMPDIR)/*.dwo && exit 1 || exit 0
+	ls $(TMPDIR)/*.dwp && exit 1 || exit 0
+	rm $(TMPDIR)/$(call BIN,main)
 endif
 endif
diff --git a/src/test/run-make-fulldeps/split-debuginfo/baz.rs b/src/test/run-make-fulldeps/split-debuginfo/baz.rs
new file mode 100644
index 000000000000..8b1a393741c9
--- /dev/null
+++ b/src/test/run-make-fulldeps/split-debuginfo/baz.rs
@@ -0,0 +1 @@
+// empty
diff --git a/src/test/run-make/emit-shared-files/Makefile b/src/test/run-make/emit-shared-files/Makefile
index 09b4c29c1dd3..cad0c9e5b815 100644
--- a/src/test/run-make/emit-shared-files/Makefile
+++ b/src/test/run-make/emit-shared-files/Makefile
@@ -23,24 +23,24 @@ invocation-only:
 
 toolchain-only:
 	$(RUSTDOC) -Z unstable-options --emit=toolchain-shared-resources --output $(TOOLCHAIN_ONLY) --resource-suffix=-xxx --extend-css z.css x.rs
-	[ -e $(TOOLCHAIN_ONLY)/storage-xxx.js ]
-	! [ -e $(TOOLCHAIN_ONLY)/SourceSerif4-It.ttf.woff2 ]
+	[ -e $(TOOLCHAIN_ONLY)/static.files/storage-*.js ]
+	[ -e $(TOOLCHAIN_ONLY)/static.files/SourceSerif4-It-*.ttf.woff2 ]
 	! [ -e $(TOOLCHAIN_ONLY)/search-index-xxx.js ]
 	! [ -e $(TOOLCHAIN_ONLY)/x/index.html ]
 	! [ -e $(TOOLCHAIN_ONLY)/theme.css ]
 
-	[ -e $(TOOLCHAIN_ONLY)/main-xxx.js ]
+	[ -e $(TOOLCHAIN_ONLY)/static.files/main-*.js ]
 	! [ -e $(TOOLCHAIN_ONLY)/y-xxx.css ]
 
 all-shared:
 	$(RUSTDOC) -Z unstable-options --emit=toolchain-shared-resources,unversioned-shared-resources --output $(ALL_SHARED) --resource-suffix=-xxx --extend-css z.css x.rs
-	[ -e $(ALL_SHARED)/storage-xxx.js ]
-	[ -e $(ALL_SHARED)/SourceSerif4-It.ttf.woff2 ]
+	[ -e $(ALL_SHARED)/static.files/storage-*.js ]
+	[ -e $(ALL_SHARED)/static.files/SourceSerif4-It-*.ttf.woff2 ]
 	! [ -e $(ALL_SHARED)/search-index-xxx.js ]
 	! [ -e $(ALL_SHARED)/settings.html ]
 	! [ -e $(ALL_SHARED)/x ]
 	! [ -e $(ALL_SHARED)/src ]
 	! [ -e $(ALL_SHARED)/theme.css ]
 
-	[ -e $(ALL_SHARED)/main-xxx.js ]
+	[ -e $(ALL_SHARED)/static.files/main-*.js ]
 	! [ -e $(ALL_SHARED)/y-xxx.css ]
diff --git a/src/test/run-make/issue-88756-default-output/output-default.stdout b/src/test/run-make/issue-88756-default-output/output-default.stdout
index 80cd08ee1673..b280698230dd 100644
--- a/src/test/run-make/issue-88756-default-output/output-default.stdout
+++ b/src/test/run-make/issue-88756-default-output/output-default.stdout
@@ -115,8 +115,6 @@ Options:
                         Provide width of the output for truncated error
                         messages
         --json CONFIG   Configure the structure of JSON diagnostics
-        --disable-minification 
-                        Disable minification applied on JS files
     -A, --allow LINT    Set lint allowed
     -W, --warn LINT     Set lint warnings
         --force-warn LINT
@@ -173,6 +171,8 @@ Options:
         --scrape-tests  Include test code when scraping examples
         --with-examples path to function call information (for displaying examples in the documentation)
                         
+        --disable-minification 
+                        removed
         --plugin-path DIR
                         removed, see issue #44136
                         <https://github.com/rust-lang/rust/issues/44136> for
diff --git a/src/test/run-make/raw-dylib-inline-cross-dylib/Makefile b/src/test/run-make/raw-dylib-inline-cross-dylib/Makefile
new file mode 100644
index 000000000000..9e603f958359
--- /dev/null
+++ b/src/test/run-make/raw-dylib-inline-cross-dylib/Makefile
@@ -0,0 +1,31 @@
+# Regression test for calling an inline function that uses a raw-dylib function.
+
+# only-windows
+
+include ../../run-make-fulldeps/tools.mk
+
+all:
+	$(RUSTC) --crate-type dylib --crate-name raw_dylib_test lib.rs -C prefer-dynamic
+	$(RUSTC) --crate-type dylib --crate-name raw_dylib_test_wrapper lib_wrapper.rs -C prefer-dynamic
+	$(RUSTC) --crate-type bin driver.rs -L "$(TMPDIR)" -C prefer-dynamic
+	# Make sure we don't find an import to the functions we expect to be inlined.
+	"$(LLVM_BIN_DIR)"/llvm-objdump -p $(TMPDIR)/driver.exe | $(CGREP) -v -e "inline_library_function"
+	"$(LLVM_BIN_DIR)"/llvm-objdump -p $(TMPDIR)/driver.exe | $(CGREP) -v -e "inline_library_function_calls_inline"
+	# Make sure we do find an import to the functions we expect to be imported.
+	"$(LLVM_BIN_DIR)"/llvm-objdump -p $(TMPDIR)/driver.exe | $(CGREP) -e "library_function"
+	$(call COMPILE_OBJ,"$(TMPDIR)"/extern_1.obj,extern_1.c)
+	$(call COMPILE_OBJ,"$(TMPDIR)"/extern_2.obj,extern_2.c)
+ifdef IS_MSVC
+	$(CC) "$(TMPDIR)"/extern_1.obj -link -dll -out:"$(TMPDIR)"/extern_1.dll -noimplib
+	$(CC) "$(TMPDIR)"/extern_2.obj -link -dll -out:"$(TMPDIR)"/extern_2.dll -noimplib
+else
+	$(CC) "$(TMPDIR)"/extern_1.obj -shared -o "$(TMPDIR)"/extern_1.dll
+	$(CC) "$(TMPDIR)"/extern_2.obj -shared -o "$(TMPDIR)"/extern_2.dll
+endif
+	$(call RUN,driver) > "$(TMPDIR)"/output.txt
+
+ifdef RUSTC_BLESS_TEST
+	cp "$(TMPDIR)"/output.txt output.txt
+else
+	$(DIFF) output.txt "$(TMPDIR)"/output.txt
+endif
diff --git a/src/test/run-make/raw-dylib-inline-cross-dylib/driver.rs b/src/test/run-make/raw-dylib-inline-cross-dylib/driver.rs
new file mode 100644
index 000000000000..f72ded7d9f63
--- /dev/null
+++ b/src/test/run-make/raw-dylib-inline-cross-dylib/driver.rs
@@ -0,0 +1,21 @@
+#![feature(raw_dylib)]
+
+extern crate raw_dylib_test;
+extern crate raw_dylib_test_wrapper;
+
+#[link(name = "extern_2", kind = "raw-dylib")]
+extern {
+    fn extern_fn_2();
+}
+
+fn main() {
+    // NOTE: The inlined call to `extern_fn_2` links against the function in extern_2.dll instead
+    // of extern_1.dll since raw-dylib symbols from the current crate are passed to the linker
+    // first, so any ambiguous names will prefer the current crate's definition.
+    raw_dylib_test::inline_library_function();
+    raw_dylib_test::library_function();
+    raw_dylib_test_wrapper::inline_library_function_calls_inline();
+    unsafe {
+        extern_fn_2();
+    }
+}
diff --git a/src/test/run-make/raw-dylib-inline-cross-dylib/extern_1.c b/src/test/run-make/raw-dylib-inline-cross-dylib/extern_1.c
new file mode 100644
index 000000000000..e5baaf5f0400
--- /dev/null
+++ b/src/test/run-make/raw-dylib-inline-cross-dylib/extern_1.c
@@ -0,0 +1,11 @@
+#include <stdio.h>
+
+__declspec(dllexport) void extern_fn_1() {
+    printf("extern_fn_1\n");
+    fflush(stdout);
+}
+
+__declspec(dllexport) void extern_fn_2() {
+    printf("extern_fn_2 in extern_1\n");
+    fflush(stdout);
+}
diff --git a/src/test/run-make/raw-dylib-inline-cross-dylib/extern_2.c b/src/test/run-make/raw-dylib-inline-cross-dylib/extern_2.c
new file mode 100644
index 000000000000..30aa4692238b
--- /dev/null
+++ b/src/test/run-make/raw-dylib-inline-cross-dylib/extern_2.c
@@ -0,0 +1,6 @@
+#include <stdio.h>
+
+__declspec(dllexport) void extern_fn_2() {
+    printf("extern_fn_2 in extern_2\n");
+    fflush(stdout);
+}
diff --git a/src/test/run-make/raw-dylib-inline-cross-dylib/lib.rs b/src/test/run-make/raw-dylib-inline-cross-dylib/lib.rs
new file mode 100644
index 000000000000..00c2c1c42d15
--- /dev/null
+++ b/src/test/run-make/raw-dylib-inline-cross-dylib/lib.rs
@@ -0,0 +1,21 @@
+#![feature(raw_dylib)]
+
+#[link(name = "extern_1", kind = "raw-dylib")]
+extern {
+    fn extern_fn_1();
+    fn extern_fn_2();
+}
+
+#[inline]
+pub fn inline_library_function() {
+    unsafe {
+        extern_fn_1();
+        extern_fn_2();
+    }
+}
+
+pub fn library_function() {
+    unsafe {
+        extern_fn_2();
+    }
+}
diff --git a/src/test/run-make/raw-dylib-inline-cross-dylib/lib_wrapper.rs b/src/test/run-make/raw-dylib-inline-cross-dylib/lib_wrapper.rs
new file mode 100644
index 000000000000..47191b8de219
--- /dev/null
+++ b/src/test/run-make/raw-dylib-inline-cross-dylib/lib_wrapper.rs
@@ -0,0 +1,6 @@
+extern crate raw_dylib_test;
+
+#[inline]
+pub fn inline_library_function_calls_inline() {
+    raw_dylib_test::inline_library_function();
+}
diff --git a/src/test/run-make/raw-dylib-inline-cross-dylib/output.txt b/src/test/run-make/raw-dylib-inline-cross-dylib/output.txt
new file mode 100644
index 000000000000..e7009baa0d4c
--- /dev/null
+++ b/src/test/run-make/raw-dylib-inline-cross-dylib/output.txt
@@ -0,0 +1,6 @@
+extern_fn_1
+extern_fn_2 in extern_2
+extern_fn_2 in extern_1
+extern_fn_1
+extern_fn_2 in extern_2
+extern_fn_2 in extern_2
diff --git a/src/test/run-make/test-benches/Makefile b/src/test/run-make/test-benches/Makefile
new file mode 100644
index 000000000000..8fc122515d0a
--- /dev/null
+++ b/src/test/run-make/test-benches/Makefile
@@ -0,0 +1,11 @@
+include ../../run-make-fulldeps/tools.mk
+
+# ignore-cross-compile
+
+all:
+	# Smoke-test that `#[bench]` isn't entirely broken.
+	$(RUSTC) --test smokebench.rs -O
+	$(call RUN,smokebench --bench)
+	$(call RUN,smokebench --bench noiter)
+	$(call RUN,smokebench --bench yesiter)
+	$(call RUN,smokebench)
diff --git a/src/test/run-make/test-benches/smokebench.rs b/src/test/run-make/test-benches/smokebench.rs
new file mode 100644
index 000000000000..ef5e5a620684
--- /dev/null
+++ b/src/test/run-make/test-benches/smokebench.rs
@@ -0,0 +1,14 @@
+#![feature(test)]
+extern crate test;
+
+#[bench]
+fn smoke_yesiter(b: &mut test::Bencher) {
+    let mut i = 0usize;
+    b.iter(|| {
+        i = i.wrapping_add(1);
+        i
+    })
+}
+
+#[bench]
+fn smoke_noiter(_: &mut test::Bencher) {}
diff --git a/src/test/run-make/valid-print-requests/Makefile b/src/test/run-make/valid-print-requests/Makefile
new file mode 100644
index 000000000000..c325e536e7c5
--- /dev/null
+++ b/src/test/run-make/valid-print-requests/Makefile
@@ -0,0 +1,4 @@
+include ../../run-make-fulldeps/tools.mk
+
+all:
+	$(RUSTC) --print uwu 2>&1 | diff - valid-print-requests.stderr
diff --git a/src/test/run-make/valid-print-requests/valid-print-requests.stderr b/src/test/run-make/valid-print-requests/valid-print-requests.stderr
new file mode 100644
index 000000000000..5191e4676486
--- /dev/null
+++ b/src/test/run-make/valid-print-requests/valid-print-requests.stderr
@@ -0,0 +1,2 @@
+error: unknown print request `uwu`. Valid print requests are: `crate-name`, `file-names`, `sysroot`, `target-libdir`, `cfg`, `calling-conventions`, `target-list`, `target-cpus`, `target-features`, `relocation-models`, `code-models`, `tls-models`, `native-static-libs`, `stack-protector-strategies`, `target-spec-json`, `link-args`, `split-debuginfo`
+
diff --git a/src/test/run-pass-valgrind/unsized-locals/by-value-trait-objects-rust-call.rs b/src/test/run-pass-valgrind/unsized-locals/by-value-trait-objects-rust-call.rs
index 7f365ce2bbaf..ece4dea9aaf6 100644
--- a/src/test/run-pass-valgrind/unsized-locals/by-value-trait-objects-rust-call.rs
+++ b/src/test/run-pass-valgrind/unsized-locals/by-value-trait-objects-rust-call.rs
@@ -1,7 +1,8 @@
 #![feature(unsized_locals)]
 #![feature(unboxed_closures)]
+#![feature(tuple_trait)]
 
-pub trait FnOnce<Args> {
+pub trait FnOnce<Args: std::marker::Tuple> {
     type Output;
     extern "rust-call" fn call_once(self, args: Args) -> Self::Output;
 }
diff --git a/src/test/run-pass-valgrind/unsized-locals/by-value-trait-objects-rust-call2.rs b/src/test/run-pass-valgrind/unsized-locals/by-value-trait-objects-rust-call2.rs
index a78b897d1941..94df2b0b83f0 100644
--- a/src/test/run-pass-valgrind/unsized-locals/by-value-trait-objects-rust-call2.rs
+++ b/src/test/run-pass-valgrind/unsized-locals/by-value-trait-objects-rust-call2.rs
@@ -1,7 +1,8 @@
 #![feature(unsized_locals)]
 #![feature(unboxed_closures)]
+#![feature(tuple_trait)]
 
-pub trait FnOnce<Args> {
+pub trait FnOnce<Args: std::marker::Tuple> {
     type Output;
     extern "rust-call" fn call_once(self, args: Args) -> Self::Output;
 }
diff --git a/src/test/rustdoc-gui/code-tags.goml b/src/test/rustdoc-gui/code-tags.goml
index 837a2c1d57f5..94c1a6525aaa 100644
--- a/src/test/rustdoc-gui/code-tags.goml
+++ b/src/test/rustdoc-gui/code-tags.goml
@@ -1,4 +1,8 @@
 // This test ensures that items and documentation code blocks are wrapped in <pre><code>
+
+// We need to disable this check because `implementors/test_docs/trait.AnotherOne.js`
+// doesn't exist.
+fail-on-request-error: false
 goto: "file://" + |DOC_PATH| + "/test_docs/fn.foo.html"
 size: (1080, 600)
 // There should be four doc codeblocks.
diff --git a/src/test/rustdoc-gui/docblock-code-block-line-number.goml b/src/test/rustdoc-gui/docblock-code-block-line-number.goml
index 911ee34be94e..fec21ad35c3e 100644
--- a/src/test/rustdoc-gui/docblock-code-block-line-number.goml
+++ b/src/test/rustdoc-gui/docblock-code-block-line-number.goml
@@ -30,10 +30,10 @@ wait-for: "#settings"
 assert-css: ("#settings", {"display": "block"})
 
 // Then, click the toggle button.
-click: "input#line-numbers + .slider"
+click: "input#line-numbers"
 wait-for: 100 // wait-for-false does not exist
 assert-false: "pre.example-line-numbers"
 
 // Finally, turn it on again.
-click: "input#line-numbers + .slider"
+click: "input#line-numbers"
 wait-for: "pre.example-line-numbers"
diff --git a/src/test/rustdoc-gui/highlight-colors.goml b/src/test/rustdoc-gui/highlight-colors.goml
index dd01dbf6148d..ff1be389dcb0 100644
--- a/src/test/rustdoc-gui/highlight-colors.goml
+++ b/src/test/rustdoc-gui/highlight-colors.goml
@@ -2,56 +2,93 @@
 goto: "file://" + |DOC_PATH| + "/src/test_docs/lib.rs.html"
 show-text: true
 
-local-storage: {"rustdoc-theme": "ayu", "rustdoc-use-system-theme": "false"}
-reload:
+define-function: (
+    "check-colors",
+    (
+        theme,
+        kw,
+        kw2,
+        prelude_ty,
+        prelude_val,
+        lifetime,
+        number,
+        string,
+        bool_val,
+        self,
+        attr,
+        macro,
+        question_mark,
+        comment,
+        doc_comment,
+    ),
+    [
+        ("local-storage", {"rustdoc-theme": |theme|, "rustdoc-use-system-theme": "false"}),
+        ("reload"),
+        ("assert-css", ("pre.rust .kw", {"color": |kw|}, ALL)),
+        ("assert-css", ("pre.rust .kw-2", {"color": |kw2|}, ALL)),
+        ("assert-css", ("pre.rust .prelude-ty", {"color": |prelude_ty|}, ALL)),
+        ("assert-css", ("pre.rust .prelude-val", {"color": |prelude_val|}, ALL)),
+        ("assert-css", ("pre.rust .lifetime", {"color": |lifetime|}, ALL)),
+        ("assert-css", ("pre.rust .number", {"color": |number|}, ALL)),
+        ("assert-css", ("pre.rust .string", {"color": |string|}, ALL)),
+        ("assert-css", ("pre.rust .bool-val", {"color": |bool_val|}, ALL)),
+        ("assert-css", ("pre.rust .self", {"color": |self|}, ALL)),
+        ("assert-css", ("pre.rust .attr", {"color": |attr|}, ALL)),
+        ("assert-css", ("pre.rust .macro", {"color": |macro|}, ALL)),
+        ("assert-css", ("pre.rust .question-mark", {"color": |question_mark|}, ALL)),
+        ("assert-css", ("pre.rust .comment", {"color": |comment|}, ALL)),
+        ("assert-css", ("pre.rust .doccomment", {"color": |doc_comment|}, ALL)),
+    ],
+)
 
-assert-css: ("pre.rust .kw", {"color": "rgb(255, 119, 51)"}, ALL)
-assert-css: ("pre.rust .kw-2", {"color": "rgb(255, 119, 51)"}, ALL)
-assert-css: ("pre.rust .prelude-ty", {"color": "rgb(105, 242, 223)"}, ALL)
-assert-css: ("pre.rust .prelude-val", {"color": "rgb(255, 119, 51)"}, ALL)
-assert-css: ("pre.rust .lifetime", {"color": "rgb(255, 119, 51)"}, ALL)
-assert-css: ("pre.rust .number", {"color": "rgb(184, 204, 82)"}, ALL)
-assert-css: ("pre.rust .string", {"color": "rgb(184, 204, 82)"}, ALL)
-assert-css: ("pre.rust .bool-val", {"color": "rgb(255, 119, 51)"}, ALL)
-assert-css: ("pre.rust .self", {"color": "rgb(54, 163, 217)"}, ALL)
-assert-css: ("pre.rust .attribute", {"color": "rgb(230, 225, 207)"}, ALL)
-assert-css: ("pre.rust .macro", {"color": "rgb(163, 122, 204)"}, ALL)
-assert-css: ("pre.rust .question-mark", {"color": "rgb(255, 144, 17)"}, ALL)
-assert-css: ("pre.rust .comment", {"color": "rgb(120, 135, 151)"}, ALL)
-assert-css: ("pre.rust .doccomment", {"color": "rgb(161, 172, 136)"}, ALL)
-
-local-storage: {"rustdoc-theme": "dark"}
-reload:
-
-assert-css: ("pre.rust .kw", {"color": "rgb(171, 138, 193)"}, ALL)
-assert-css: ("pre.rust .kw-2", {"color": "rgb(118, 154, 203)"}, ALL)
-assert-css: ("pre.rust .prelude-ty", {"color": "rgb(118, 154, 203)"}, ALL)
-assert-css: ("pre.rust .prelude-val", {"color": "rgb(238, 104, 104)"}, ALL)
-assert-css: ("pre.rust .lifetime", {"color": "rgb(217, 127, 38)"}, ALL)
-assert-css: ("pre.rust .number", {"color": "rgb(131, 163, 0)"}, ALL)
-assert-css: ("pre.rust .string", {"color": "rgb(131, 163, 0)"}, ALL)
-assert-css: ("pre.rust .bool-val", {"color": "rgb(238, 104, 104)"}, ALL)
-assert-css: ("pre.rust .self", {"color": "rgb(238, 104, 104)"}, ALL)
-assert-css: ("pre.rust .attribute", {"color": "rgb(238, 104, 104)"}, ALL)
-assert-css: ("pre.rust .macro", {"color": "rgb(62, 153, 159)"}, ALL)
-assert-css: ("pre.rust .question-mark", {"color": "rgb(255, 144, 17)"}, ALL)
-assert-css: ("pre.rust .comment", {"color": "rgb(141, 141, 139)"}, ALL)
-assert-css: ("pre.rust .doccomment", {"color": "rgb(140, 163, 117)"}, ALL)
-
-local-storage: {"rustdoc-theme": "light"}
-reload:
-
-assert-css: ("pre.rust .kw", {"color": "rgb(137, 89, 168)"}, ALL)
-assert-css: ("pre.rust .kw-2", {"color": "rgb(66, 113, 174)"}, ALL)
-assert-css: ("pre.rust .prelude-ty", {"color": "rgb(66, 113, 174)"}, ALL)
-assert-css: ("pre.rust .prelude-val", {"color": "rgb(200, 40, 41)"}, ALL)
-assert-css: ("pre.rust .lifetime", {"color": "rgb(183, 101, 20)"}, ALL)
-assert-css: ("pre.rust .number", {"color": "rgb(113, 140, 0)"}, ALL)
-assert-css: ("pre.rust .string", {"color": "rgb(113, 140, 0)"}, ALL)
-assert-css: ("pre.rust .bool-val", {"color": "rgb(200, 40, 41)"}, ALL)
-assert-css: ("pre.rust .self", {"color": "rgb(200, 40, 41)"}, ALL)
-assert-css: ("pre.rust .attribute", {"color": "rgb(200, 40, 41)"}, ALL)
-assert-css: ("pre.rust .macro", {"color": "rgb(62, 153, 159)"}, ALL)
-assert-css: ("pre.rust .question-mark", {"color": "rgb(255, 144, 17)"}, ALL)
-assert-css: ("pre.rust .comment", {"color": "rgb(142, 144, 140)"}, ALL)
-assert-css: ("pre.rust .doccomment", {"color": "rgb(77, 77, 76)"}, ALL)
+call-function: ("check-colors", {
+    "theme": "ayu",
+    "kw": "rgb(255, 119, 51)",
+    "kw2": "rgb(255, 119, 51)",
+    "prelude_ty": "rgb(105, 242, 223)",
+    "prelude_val": "rgb(255, 119, 51)",
+    "lifetime": "rgb(255, 119, 51)",
+    "number": "rgb(184, 204, 82)",
+    "string": "rgb(184, 204, 82)",
+    "bool_val": "rgb(255, 119, 51)",
+    "self": "rgb(54, 163, 217)",
+    "attr": "rgb(230, 225, 207)",
+    "macro": "rgb(163, 122, 204)",
+    "question_mark": "rgb(255, 144, 17)",
+    "comment": "rgb(120, 135, 151)",
+    "doc_comment": "rgb(161, 172, 136)",
+})
+call-function: ("check-colors", {
+    "theme": "dark",
+    "kw": "rgb(171, 138, 193)",
+    "kw2": "rgb(118, 154, 203)",
+    "prelude_ty": "rgb(118, 154, 203)",
+    "prelude_val": "rgb(238, 104, 104)",
+    "lifetime": "rgb(217, 127, 38)",
+    "number": "rgb(131, 163, 0)",
+    "string": "rgb(131, 163, 0)",
+    "bool_val": "rgb(238, 104, 104)",
+    "self": "rgb(238, 104, 104)",
+    "attr": "rgb(238, 104, 104)",
+    "macro": "rgb(62, 153, 159)",
+    "question_mark": "rgb(255, 144, 17)",
+    "comment": "rgb(141, 141, 139)",
+    "doc_comment": "rgb(140, 163, 117)",
+})
+call-function: ("check-colors", {
+    "theme": "light",
+    "kw": "rgb(137, 89, 168)",
+    "kw2": "rgb(66, 113, 174)",
+    "prelude_ty": "rgb(66, 113, 174)",
+    "prelude_val": "rgb(200, 40, 41)",
+    "lifetime": "rgb(183, 101, 20)",
+    "number": "rgb(113, 140, 0)",
+    "string": "rgb(113, 140, 0)",
+    "bool_val": "rgb(200, 40, 41)",
+    "self": "rgb(200, 40, 41)",
+    "attr": "rgb(200, 40, 41)",
+    "macro": "rgb(62, 153, 159)",
+    "question_mark": "rgb(255, 144, 17)",
+    "comment": "rgb(142, 144, 140)",
+    "doc_comment": "rgb(77, 77, 76)",
+})
diff --git a/src/test/rustdoc-gui/huge-logo.goml b/src/test/rustdoc-gui/huge-logo.goml
new file mode 100644
index 000000000000..01f06771c15a
--- /dev/null
+++ b/src/test/rustdoc-gui/huge-logo.goml
@@ -0,0 +1,21 @@
+// huge_logo crate has a custom 712x860 logo
+// test to ensure the maximum size in the layout works correctly
+goto: "file://" + |DOC_PATH| + "/huge_logo/index.html"
+
+size: (1280, 1024)
+// offsetWidth = width of sidebar
+assert-property: (".sidebar .logo-container", {"offsetWidth": "200", "offsetHeight": 100})
+assert-property: (".sidebar .logo-container img", {"offsetWidth": "100", "offsetHeight": 100})
+
+size: (400, 600)
+// offset = size + margin
+assert-property: (".mobile-topbar .logo-container", {"offsetWidth": "55", "offsetHeight": 45})
+assert-property: (".mobile-topbar .logo-container img", {"offsetWidth": "35", "offsetHeight": 35})
+
+goto: "file://" + |DOC_PATH| + "/src/huge_logo/lib.rs.html"
+
+size: (1280, 1024)
+assert-property: (".sub-logo-container", {"offsetWidth": "60", "offsetHeight": 60})
+
+size: (400, 600)
+assert-property: (".sub-logo-container", {"offsetWidth": "35", "offsetHeight": 35})
diff --git a/src/test/rustdoc-gui/item-decl-colors.goml b/src/test/rustdoc-gui/item-decl-colors.goml
index ce688287a743..9a46f256056f 100644
--- a/src/test/rustdoc-gui/item-decl-colors.goml
+++ b/src/test/rustdoc-gui/item-decl-colors.goml
@@ -1,4 +1,9 @@
 // This test ensures that the color of the items in the type decl are working as expected.
+
+// We need to disable this check because `implementors/test_docs/trait.TraitWithoutGenerics.js`
+// doesn't exist.
+fail-on-request-error: false
+
 define-function: (
     "check-colors",
     (
diff --git a/src/test/rustdoc-gui/method-margins.goml b/src/test/rustdoc-gui/method-margins.goml
new file mode 100644
index 000000000000..397bcd40b36c
--- /dev/null
+++ b/src/test/rustdoc-gui/method-margins.goml
@@ -0,0 +1,17 @@
+goto: "file://" + |DOC_PATH| + "/test_docs/trait_members/struct.HasTrait.html#impl-TraitMembers-for-HasTrait"
+
+assert-count: ("#trait-implementations-list > .rustdoc-toggle", 1)
+
+compare-elements-css: (
+    // compare margin on type with margin on method
+    "#trait-implementations-list .impl-items > .rustdoc-toggle:nth-child(1) > summary",
+    "#trait-implementations-list .impl-items > .rustdoc-toggle:nth-child(2) > summary",
+    ["margin"]
+)
+
+compare-elements-css: (
+    // compare margin on type with margin on method
+    "#trait-implementations-list .impl-items > .rustdoc-toggle:nth-child(1)",
+    "#trait-implementations-list .impl-items > .rustdoc-toggle:nth-child(2)",
+    ["margin"]
+)
diff --git a/src/test/rustdoc-gui/no-docblock.goml b/src/test/rustdoc-gui/no-docblock.goml
index 2366a60f5c61..17a955064d73 100644
--- a/src/test/rustdoc-gui/no-docblock.goml
+++ b/src/test/rustdoc-gui/no-docblock.goml
@@ -1,4 +1,9 @@
 // This test checks that there are margins applied to methods with no docblocks.
+
+// We need to disable this check because `implementors/test_docs/trait.TraitWithNoDocblock.js`
+// doesn't exist.
+fail-on-request-error: false
+
 goto: "file://" + |DOC_PATH| + "/test_docs/trait.TraitWithNoDocblocks.html"
 // Check that the two methods are more than 24px apart.
 compare-elements-position-near-false: ("//*[@id='tymethod.first_fn']", "//*[@id='tymethod.second_fn']", {"y": 24})
diff --git a/src/test/rustdoc-gui/notable-trait.goml b/src/test/rustdoc-gui/notable-trait.goml
index 997fb5cf0ade..4c3943d88583 100644
--- a/src/test/rustdoc-gui/notable-trait.goml
+++ b/src/test/rustdoc-gui/notable-trait.goml
@@ -22,9 +22,26 @@ assert-position: (
 )
 assert-position: (
     "//*[@id='method.create_an_iterator_from_read']//*[@class='notable-traits']",
-    {"x": 951},
+    {"x": 955},
 )
-
+// The tooltip should be below the `i`
+// Also, clicking the tooltip should bring its text into the DOM
+assert-count: ("//*[@class='notable popover']", 0)
+click: "//*[@id='method.create_an_iterator_from_read']//*[@class='notable-traits']"
+assert-count: ("//*[@class='notable popover']", 1)
+compare-elements-position-near: (
+    "//*[@id='method.create_an_iterator_from_read']//*[@class='notable-traits']",
+    "//*[@class='notable popover']",
+    {"y": 30}
+)
+compare-elements-position-false: (
+    "//*[@id='method.create_an_iterator_from_read']//*[@class='notable-traits']",
+    "//*[@class='notable popover']",
+    ("x")
+)
+click: "//*[@id='method.create_an_iterator_from_read']//*[@class='notable-traits']"
+move-cursor-to: "//h1"
+assert-count: ("//*[@class='notable popover']", 0)
 
 // Now only the `i` should be on the next line.
 size: (1055, 600)
@@ -55,7 +72,7 @@ assert-position: (
 )
 assert-position: (
     "//*[@id='method.create_an_iterator_from_read']//*[@class='notable-traits']",
-    {"x": 519},
+    {"x": 523},
 )
 
 // Checking on mobile now.
@@ -79,13 +96,126 @@ assert-position: (
 )
 assert-position: (
     "//*[@id='method.create_an_iterator_from_read']//*[@class='notable-traits']",
-    {"x": 289},
+    {"x": 293},
+)
+// The tooltip should STILL be below `i`
+click: "//*[@id='method.create_an_iterator_from_read']//*[@class='notable-traits']"
+assert-count: ("//*[@class='notable popover']", 1)
+compare-elements-position-near: (
+    "//*[@id='method.create_an_iterator_from_read']//*[@class='notable-traits']",
+    "//*[@class='notable popover']",
+    {"y": 30}
+)
+compare-elements-position-false: (
+    "//*[@id='method.create_an_iterator_from_read']//*[@class='notable-traits']",
+    "//*[@class='notable popover']",
+    ("x")
+)
+assert-position: (
+    "//*[@class='notable popover']",
+    {"x": 0}
+)
+click: "//*[@id='method.create_an_iterator_from_read']//*[@class='notable-traits']"
+move-cursor-to: "//h1"
+assert-count: ("//*[@class='notable popover']", 0)
+
+// Now check the colors.
+define-function: (
+    "check-colors",
+    (theme, header_color, content_color, type_color, trait_color),
+    [
+        ("goto", "file://" + |DOC_PATH| + "/test_docs/struct.NotableStructWithLongName.html"),
+        // This is needed to ensure that the text color is computed.
+        ("show-text", true),
+
+        // Setting the theme.
+        ("local-storage", {"rustdoc-theme": |theme|, "rustdoc-use-system-theme": "false"}),
+        // We reload the page so the local storage settings are being used.
+        ("reload"),
+
+        ("move-cursor-to", "//*[@id='method.create_an_iterator_from_read']//*[@class='notable-traits']"),
+        ("assert-count", (".notable.popover", 1)),
+
+        ("assert-css", (
+             ".notable.popover h3",
+             {"color": |header_color|},
+             ALL,
+        )),
+        ("assert-css", (
+             ".notable.popover pre",
+             {"color": |content_color|},
+             ALL,
+        )),
+        ("assert-css", (
+             ".notable.popover pre a.struct",
+             {"color": |type_color|},
+             ALL,
+        )),
+        ("assert-css", (
+             ".notable.popover pre a.trait",
+             {"color": |trait_color|},
+             ALL,
+        )),
+    ]
 )
 
-// Checking on very small mobile. The `i` should be on its own line.
-size: (365, 600)
-compare-elements-position-false: (
-    "//*[@id='method.create_an_iterator_from_read']//a[text()='NotableStructWithLongName']",
-    "//*[@id='method.create_an_iterator_from_read']//*[@class='notable-traits']",
-    ("y", "x"),
+call-function: (
+    "check-colors",
+    {
+        "theme": "ayu",
+        "content_color": "rgb(230, 225, 207)",
+        "header_color": "rgb(255, 255, 255)",
+        "type_color": "rgb(255, 160, 165)",
+        "trait_color": "rgb(57, 175, 215)",
+    },
 )
+
+call-function: (
+    "check-colors",
+    {
+        "theme": "dark",
+        "content_color": "rgb(221, 221, 221)",
+        "header_color": "rgb(221, 221, 221)",
+        "type_color": "rgb(45, 191, 184)",
+        "trait_color": "rgb(183, 140, 242)",
+    },
+)
+
+call-function: (
+    "check-colors",
+    {
+        "theme": "light",
+        "content_color": "rgb(0, 0, 0)",
+        "header_color": "rgb(0, 0, 0)",
+        "type_color": "rgb(173, 55, 138)",
+        "trait_color": "rgb(110, 79, 201)",
+    },
+)
+
+reload:
+
+// Check that pressing escape works
+click: "//*[@id='method.create_an_iterator_from_read']//*[@class='notable-traits']"
+move-cursor-to: "//*[@class='notable popover']"
+assert-count: ("//*[@class='notable popover']", 1)
+press-key: "Escape"
+assert-count: ("//*[@class='notable popover']", 0)
+
+// Check that clicking outside works.
+click: "//*[@id='method.create_an_iterator_from_read']//*[@class='notable-traits']"
+assert-count: ("//*[@class='notable popover']", 1)
+click: ".search-input"
+assert-count: ("//*[@class='notable popover']", 0)
+
+// Check that pressing tab over and over works.
+click: "//*[@id='method.create_an_iterator_from_read']//*[@class='notable-traits']"
+move-cursor-to: "//*[@class='notable popover']"
+assert-count: ("//*[@class='notable popover']", 1)
+press-key: "Tab"
+press-key: "Tab"
+press-key: "Tab"
+press-key: "Tab"
+press-key: "Tab"
+press-key: "Tab"
+press-key: "Tab"
+assert-count: ("//*[@class='notable popover']", 0)
diff --git a/src/test/rustdoc-gui/run-on-hover.goml b/src/test/rustdoc-gui/run-on-hover.goml
index 6c785e1c4bba..57d63049f28c 100644
--- a/src/test/rustdoc-gui/run-on-hover.goml
+++ b/src/test/rustdoc-gui/run-on-hover.goml
@@ -1,7 +1,54 @@
 // Example code blocks sometimes have a "Run" button to run them on the
 // Playground. That button is hidden until the user hovers over the code block.
-// This test checks that it is hidden, and that it shows on hover.
+// This test checks that it is hidden, and that it shows on hover. It also
+// checks for its color.
 goto: "file://" + |DOC_PATH| + "/test_docs/fn.foo.html"
-assert-css: (".test-arrow", {"visibility": "hidden"})
-move-cursor-to: ".example-wrap"
-assert-css: (".test-arrow", {"visibility": "visible"})
+show-text: true
+
+define-function: (
+    "check-run-button",
+    (theme, color, background, hover_color, hover_background),
+    [
+        ("local-storage", {"rustdoc-theme": |theme|, "rustdoc-use-system-theme": "false"}),
+        ("reload"),
+        ("assert-css", (".test-arrow", {"visibility": "hidden"})),
+        ("move-cursor-to", ".example-wrap"),
+        ("assert-css", (".test-arrow", {
+            "visibility": "visible",
+            "color": |color|,
+            "background-color": |background|,
+            "font-size": "22px",
+            "border-radius": "5px",
+        })),
+        ("move-cursor-to", ".test-arrow"),
+        ("assert-css", (".test-arrow:hover", {
+            "visibility": "visible",
+            "color": |hover_color|,
+            "background-color": |hover_background|,
+            "font-size": "22px",
+            "border-radius": "5px",
+        })),
+    ],
+)
+
+call-function: ("check-run-button", {
+    "theme": "ayu",
+    "color": "rgb(120, 135, 151)",
+    "background": "rgba(57, 175, 215, 0.09)",
+    "hover_color": "rgb(197, 197, 197)",
+    "hover_background": "rgba(57, 175, 215, 0.37)",
+})
+call-function: ("check-run-button", {
+    "theme": "dark",
+    "color": "rgb(222, 222, 222)",
+    "background": "rgba(78, 139, 202, 0.2)",
+    "hover_color": "rgb(222, 222, 222)",
+    "hover_background": "rgb(78, 139, 202)",
+})
+call-function: ("check-run-button", {
+    "theme": "light",
+    "color": "rgb(245, 245, 245)",
+    "background": "rgba(78, 139, 202, 0.2)",
+    "hover_color": "rgb(245, 245, 245)",
+    "hover_background": "rgb(78, 139, 202)",
+})
diff --git a/src/test/rustdoc-gui/rust-logo.goml b/src/test/rustdoc-gui/rust-logo.goml
index 6c8dc8594193..816cc9abd693 100644
--- a/src/test/rustdoc-gui/rust-logo.goml
+++ b/src/test/rustdoc-gui/rust-logo.goml
@@ -17,6 +17,15 @@ define-function: (
         ("local-storage", {"rustdoc-theme": |theme|, "rustdoc-use-system-theme": "false"}),
         ("reload"),
         ("assert-css", (".rust-logo", {"filter": |filter|})),
+        // Now we check that the non-rust logos don't have a CSS filter set.
+        ("goto", "file://" + |DOC_PATH| + "/huge_logo/index.html"),
+        // Changing theme on the new page (again...).
+        ("local-storage", {"rustdoc-theme": |theme|, "rustdoc-use-system-theme": "false"}),
+        ("reload"),
+        // Check there is no rust logo
+        ("assert-false", ".rust-logo"),
+        // Check there is no filter.
+        ("assert-css", (".sidebar .logo-container img", {"filter": "none"})),
     ],
 )
 
diff --git a/src/test/rustdoc-gui/search-filter.goml b/src/test/rustdoc-gui/search-filter.goml
index 27db816e6851..e0228694eec5 100644
--- a/src/test/rustdoc-gui/search-filter.goml
+++ b/src/test/rustdoc-gui/search-filter.goml
@@ -14,6 +14,7 @@ click: "#crate-search"
 // We select "lib2" option then press enter to change the filter.
 press-key: "ArrowDown"
 press-key: "ArrowDown"
+press-key: "ArrowDown"
 press-key: "Enter"
 // Waiting for the search results to appear...
 wait-for: "#titles"
@@ -37,6 +38,7 @@ assert-property: ("#crate-search", {"value": "lib2"})
 click: "#crate-search"
 press-key: "ArrowUp"
 press-key: "ArrowUp"
+press-key: "ArrowUp"
 press-key: "Enter"
 // Waiting for the search results to appear...
 wait-for: "#titles"
diff --git a/src/test/rustdoc-gui/search-keyboard.goml b/src/test/rustdoc-gui/search-keyboard.goml
new file mode 100644
index 000000000000..be642fc49971
--- /dev/null
+++ b/src/test/rustdoc-gui/search-keyboard.goml
@@ -0,0 +1,28 @@
+// Checks that the search tab results work correctly with function signature syntax
+// First, try a search-by-name
+goto: "file://" + |DOC_PATH| + "/test_docs/index.html"
+write: (".search-input", "Foo")
+// To be SURE that the search will be run.
+press-key: 'Enter'
+// Waiting for the search results to appear...
+wait-for: "#titles"
+
+// Now use the keyboard commands to switch to the third result.
+press-key: "ArrowDown"
+press-key: "ArrowDown"
+press-key: "ArrowDown"
+assert: ".search-results.active > a:focus:nth-of-type(3)"
+
+// Now switch to the second tab, then back to the first one, then arrow back up.
+press-key: "ArrowRight"
+assert: ".search-results.active:nth-of-type(2) > a:focus:nth-of-type(1)"
+press-key: "ArrowLeft"
+assert: ".search-results.active:nth-of-type(1) > a:focus:nth-of-type(3)"
+press-key: "ArrowUp"
+assert: ".search-results.active > a:focus:nth-of-type(2)"
+press-key: "ArrowUp"
+assert: ".search-results.active > a:focus:nth-of-type(1)"
+press-key: "ArrowUp"
+assert: ".search-input:focus"
+press-key: "ArrowDown"
+assert: ".search-results.active > a:focus:nth-of-type(1)"
diff --git a/src/test/rustdoc-gui/search-no-result.goml b/src/test/rustdoc-gui/search-no-result.goml
new file mode 100644
index 000000000000..b88be32c94a4
--- /dev/null
+++ b/src/test/rustdoc-gui/search-no-result.goml
@@ -0,0 +1,36 @@
+// The goal of this test is to check the color of the "no result" links.
+goto: "file://" + |DOC_PATH| + "/lib2/index.html?search=sdkfskjfsdks"
+show-text: true
+
+define-function: (
+    "check-no-result",
+    (theme, link, link_hover),
+    [
+        // Changing theme.
+        ("local-storage", {"rustdoc-theme": |theme|, "rustdoc-use-system-theme": "false"}),
+        ("reload"),
+        ("wait-for", "#results"),
+        ("assert", ".search-failed.active"),
+        ("assert-css", ("#results a", {"color": |link|}, ALL)),
+        ("move-cursor-to", "#results a"),
+        ("assert-css", ("#results a:hover", {"color": |link_hover|})),
+        // Moving the cursor to some other place to not create issues with next function run.
+        ("move-cursor-to", ".search-input"),
+    ]
+)
+
+call-function: ("check-no-result", {
+    "theme": "ayu",
+    "link": "rgb(57, 175, 215)",
+    "link_hover": "rgb(57, 175, 215)",
+})
+call-function: ("check-no-result", {
+    "theme": "dark",
+    "link": "rgb(210, 153, 29)",
+    "link_hover": "rgb(210, 153, 29)",
+})
+call-function: ("check-no-result", {
+    "theme": "light",
+    "link": "rgb(56, 115, 173)",
+    "link_hover": "rgb(56, 115, 173)",
+})
diff --git a/src/test/rustdoc-gui/search-result-color.goml b/src/test/rustdoc-gui/search-result-color.goml
index 69bb30df954b..d437ad75970b 100644
--- a/src/test/rustdoc-gui/search-result-color.goml
+++ b/src/test/rustdoc-gui/search-result-color.goml
@@ -67,7 +67,7 @@ reload:
 // Waiting for the search results to appear...
 wait-for: "#titles"
 assert-css: (
-    "//*[@class='desc']//*[text()='Just a normal struct.']",
+    "//*[@class='desc'][text()='Just a normal struct.']",
     {"color": "rgb(197, 197, 197)"},
 )
 assert-css: (
@@ -75,6 +75,12 @@ assert-css: (
     {"color": "rgb(0, 150, 207)"},
 )
 
+// Checking the color of the bottom border.
+assert-css: (
+    ".search-results > a",
+    {"border-bottom-color": "rgba(170, 170, 170, 0.2)"}
+)
+
 // Checking the color of "keyword" text.
 assert-css: (
     "//*[@class='result-name']//*[text()='(keyword)']",
@@ -153,7 +159,7 @@ assert-css: (
 )
 
 // Checking color and background on hover.
-move-cursor-to: "//*[@class='desc']//*[text()='Just a normal struct.']"
+move-cursor-to: "//*[@class='desc'][text()='Just a normal struct.']"
 assert-css: (
     "//*[@class='result-name']/*[text()='test_docs::']",
     {"color": "rgb(255, 255, 255)"},
@@ -173,7 +179,7 @@ reload:
 // Waiting for the search results to appear...
 wait-for: "#titles"
 assert-css: (
-    "//*[@class='desc']//*[text()='Just a normal struct.']",
+    "//*[@class='desc'][text()='Just a normal struct.']",
     {"color": "rgb(221, 221, 221)"},
 )
 assert-css: (
@@ -181,6 +187,12 @@ assert-css: (
     {"color": "rgb(221, 221, 221)"},
 )
 
+// Checking the color of the bottom border.
+assert-css: (
+    ".search-results > a",
+    {"border-bottom-color": "rgba(170, 170, 170, 0.2)"}
+)
+
 // Checking the color for "keyword" text.
 assert-css: (
     "//*[@class='result-name']//*[text()='(keyword)']",
@@ -264,7 +276,7 @@ reload:
 // Waiting for the search results to appear...
 wait-for: "#titles"
 assert-css: (
-    "//*[@class='desc']//*[text()='Just a normal struct.']",
+    "//*[@class='desc'][text()='Just a normal struct.']",
     {"color": "rgb(0, 0, 0)"},
 )
 assert-css: (
@@ -272,6 +284,12 @@ assert-css: (
     {"color": "rgb(0, 0, 0)"},
 )
 
+// Checking the color of the bottom border.
+assert-css: (
+    ".search-results > a",
+    {"border-bottom-color": "rgba(170, 170, 170, 0.2)"}
+)
+
 // Checking the color for "keyword" text.
 assert-css: (
     "//*[@class='result-name']//*[text()='(keyword)']",
diff --git a/src/test/rustdoc-gui/search-result-display.goml b/src/test/rustdoc-gui/search-result-display.goml
index 053bfd8c905d..fa349c872ae2 100644
--- a/src/test/rustdoc-gui/search-result-display.goml
+++ b/src/test/rustdoc-gui/search-result-display.goml
@@ -7,7 +7,7 @@ press-key: 'Enter'
 wait-for: "#crate-search"
 // The width is returned by "getComputedStyle" which returns the exact number instead of the
 // CSS rule which is "50%"...
-assert-css: (".search-results div.desc", {"width": "318px"})
+assert-css: (".search-results div.desc", {"width": "310px"})
 size: (600, 100)
 // As counter-intuitive as it may seem, in this width, the width is "100%", which is why
 // when computed it's larger.
@@ -35,3 +35,43 @@ assert-css: ("#crate-search", {"width": "527px"})
 assert-css: (".search-results-title", {"height": "44px", "width": "640px"})
 // And we check that the `<select>` isn't bigger than its container (".search-results-title").
 assert-css: ("#search", {"width": "640px"})
+
+// Now checking that the crate filter is working as expected too.
+show-text: true
+define-function: (
+    "check-filter",
+    (theme, border, filter, hover_border, hover_filter),
+    [
+        ("local-storage", {"rustdoc-theme": |theme|, "rustdoc-use-system-theme": "false"}),
+        ("reload"),
+        ("wait-for", "#crate-search"),
+        ("assert-css", ("#crate-search", {"border": "1px solid " + |border|})),
+        ("assert-css", ("#crate-search-div::after", {"filter": |filter|})),
+        ("move-cursor-to", "#crate-search"),
+        ("assert-css", ("#crate-search", {"border": "1px solid " + |hover_border|})),
+        ("assert-css", ("#crate-search-div::after", {"filter": |hover_filter|})),
+        ("move-cursor-to", ".search-input"),
+    ],
+)
+
+call-function: ("check-filter", {
+    "theme": "ayu",
+    "border": "rgb(92, 103, 115)",
+    "filter": "invert(0.41) sepia(0.12) saturate(4.87) hue-rotate(171deg) brightness(0.94) contrast(0.94)",
+    "hover_border": "rgb(224, 224, 224)",
+    "hover_filter": "invert(0.98) sepia(0.12) saturate(0.81) hue-rotate(343deg) brightness(1.13) contrast(0.76)",
+})
+call-function: ("check-filter", {
+    "theme": "dark",
+    "border": "rgb(224, 224, 224)",
+    "filter": "invert(0.94) sepia(0) saturate(7.21) hue-rotate(255deg) brightness(0.9) contrast(0.9)",
+    "hover_border": "rgb(33, 150, 243)",
+    "hover_filter": "invert(0.69) sepia(0.6) saturate(66.13) hue-rotate(184deg) brightness(1) contrast(0.91)",
+})
+call-function: ("check-filter", {
+    "theme": "light",
+    "border": "rgb(224, 224, 224)",
+    "filter": "invert(1) sepia(0) saturate(42.23) hue-rotate(289deg) brightness(1.14) contrast(0.76)",
+    "hover_border": "rgb(113, 113, 113)",
+    "hover_filter": "invert(0.44) sepia(0.18) saturate(0.23) hue-rotate(317deg) brightness(0.96) contrast(0.93)",
+})
diff --git a/src/test/rustdoc-gui/settings.goml b/src/test/rustdoc-gui/settings.goml
index f258f4d2a838..7e7971d47fbc 100644
--- a/src/test/rustdoc-gui/settings.goml
+++ b/src/test/rustdoc-gui/settings.goml
@@ -48,7 +48,8 @@ assert: ".setting-line.hidden #preferred-light-theme"
 assert-property: ("#theme .choices #theme-dark", {"checked": "true"})
 
 // Some style checks...
-// First we check the "default" display.
+move-cursor-to: "#settings-menu > a"
+// First we check the "default" display for radio buttons.
 assert-css: (
     "#theme-dark",
     {
@@ -57,7 +58,7 @@ assert-css: (
     },
 )
 assert-css: ("#theme-light", {"border-color": "rgb(221, 221, 221)", "box-shadow": "none"})
-// Let's start with the hover.
+// Let's start with the hover for radio buttons.
 move-cursor-to: "#theme-dark"
 assert-css: (
     "#theme-dark",
@@ -69,7 +70,7 @@ assert-css: (
 move-cursor-to: "#theme-light"
 assert-css: ("#theme-light", {"border-color": "rgb(33, 150, 243)", "box-shadow": "none"})
 move-cursor-to: "#theme-ayu"
-// Let's now check with the focus.
+// Let's now check with the focus for radio buttons.
 focus: "#theme-dark"
 assert-css: (
     "#theme-dark",
@@ -86,7 +87,7 @@ assert-css: (
         "box-shadow": "rgb(33, 150, 243) 0px 0px 1px 1px",
     },
 )
-// Now we check we both focus and hover.
+// Now we check we both focus and hover for radio buttons.
 move-cursor-to: "#theme-dark"
 focus: "#theme-dark"
 assert-css: (
@@ -106,6 +107,80 @@ assert-css: (
     },
 )
 
+// First we check the "default" display for toggles.
+assert-css: (
+    "#auto-hide-large-items",
+    {
+        "background-color": "rgb(33, 150, 243)",
+        "border-color": "rgb(221, 221, 221)",
+    },
+)
+assert-css: (
+    "#use-system-theme",
+    {
+        "background-color": "rgba(0, 0, 0, 0)",
+        "border-color": "rgb(221, 221, 221)",
+    }
+)
+// Let's start with the hover for toggles.
+move-cursor-to: "#auto-hide-large-items"
+assert-css: (
+    "#auto-hide-large-items",
+    {
+        "background-color": "rgb(33, 150, 243)",
+        "border-color": "rgb(33, 150, 243)",
+    },
+)
+move-cursor-to: "#use-system-theme"
+assert-css: (
+    "#use-system-theme",
+    {
+        "background-color": "rgba(0, 0, 0, 0)",
+        "border-color": "rgb(33, 150, 243)",
+    }
+)
+move-cursor-to: "#settings-menu > a"
+// Let's now check with the focus for toggles.
+focus: "#auto-hide-large-items"
+assert-css: (
+    "#auto-hide-large-items",
+    {
+        "background-color": "rgb(33, 150, 243)",
+        "border-color": "rgb(221, 221, 221)",
+        "box-shadow": "rgb(33, 150, 243) 0px 0px 1px 1px",
+    },
+)
+focus: "#use-system-theme"
+assert-css: (
+    "#use-system-theme",
+    {
+        "background-color": "rgba(0, 0, 0, 0)",
+        "border-color": "rgb(221, 221, 221)",
+        "box-shadow": "rgb(33, 150, 243) 0px 0px 1px 1px",
+    },
+)
+// Now we check we both focus and hover for toggles.
+move-cursor-to: "#auto-hide-large-items"
+focus: "#auto-hide-large-items"
+assert-css: (
+    "#auto-hide-large-items",
+    {
+        "background-color": "rgb(33, 150, 243)",
+        "border-color": "rgb(33, 150, 243)",
+        "box-shadow": "rgb(33, 150, 243) 0px 0px 1px 1px",
+    },
+)
+move-cursor-to: "#use-system-theme"
+focus: "#use-system-theme"
+assert-css: (
+    "#use-system-theme",
+    {
+        "background-color": "rgba(0, 0, 0, 0)",
+        "border-color": "rgb(33, 150, 243)",
+        "box-shadow": "rgb(33, 150, 243) 0px 0px 1px 1px",
+    },
+)
+
 // We now switch the display.
 click: "#use-system-theme"
 // Wait for the hidden element to show up.
@@ -118,7 +193,7 @@ assert: ".setting-line.hidden #theme"
 assert-text: ("#preferred-dark-theme .setting-name", "Preferred dark theme")
 assert-text: ("#preferred-light-theme .setting-name", "Preferred light theme")
 
-// We now check that clicking on the "sliders"' text is like clicking on the slider.
+// We now check that clicking on the toggles' text is like clicking on the checkbox.
 // To test it, we use the "Disable keyboard shortcuts".
 local-storage: {"rustdoc-disable-shortcuts": "false"}
 click: ".setting-line:last-child .toggle .label"
@@ -141,10 +216,7 @@ assert-css: ("#settings-menu .popover", {"display": "none"})
 // Now we go to the settings page to check that the CSS is loaded as expected.
 goto: "file://" + |DOC_PATH| + "/settings.html"
 wait-for: "#settings"
-assert-css: (
-    ".setting-line .toggle .slider",
-    {"width": "45px", "margin-right": "20px", "border": "0px none rgb(0, 0, 0)"},
-)
+assert-css: (".setting-line", {"position": "relative"})
 
 assert-attribute-false: ("#settings", {"class": "popover"}, CONTAINS)
 compare-elements-position: (".sub form", "#settings", ("x"))
@@ -162,4 +234,4 @@ reload:
 size: (300, 1000)
 click: "#settings-menu"
 wait-for: "#settings"
-assert-css: ("#settings .slider", {"width": "45px"}, ALL)
+assert-css: (".setting-line", {"position": "relative"})
diff --git a/src/test/rustdoc-gui/sidebar-links-color.goml b/src/test/rustdoc-gui/sidebar-links-color.goml
index 18a1a3fadea5..7ef7ec90cd26 100644
--- a/src/test/rustdoc-gui/sidebar-links-color.goml
+++ b/src/test/rustdoc-gui/sidebar-links-color.goml
@@ -4,230 +4,168 @@ goto: "file://" + |DOC_PATH| + "/test_docs/struct.Foo.html"
 // This is needed so that the text color is computed.
 show-text: true
 
-// Ayu theme
-local-storage: {
-    "rustdoc-theme": "ayu",
-    "rustdoc-use-system-theme": "false",
-}
-reload:
-
-// Struct
-assert-css: (
-    ".sidebar .block.struct a:not(.current)",
-    {"color": "rgb(83, 177, 219)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-move-cursor-to: ".sidebar .block.struct a:not(.current)"
-assert-css: (
-    ".sidebar .block.struct a:hover",
-    {"color": "rgb(255, 180, 76)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-// Enum
-assert-css: (
-    ".sidebar .block.enum a",
-    {"color": "rgb(83, 177, 219)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-move-cursor-to: ".sidebar .block.enum a"
-assert-css: (
-    ".sidebar .block.enum a:hover",
-    {"color": "rgb(255, 180, 76)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-// Union
-assert-css: (
-    ".sidebar .block.union a",
-    {"color": "rgb(83, 177, 219)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-move-cursor-to: ".sidebar .block.union a"
-assert-css: (
-    ".sidebar .block.union a:hover",
-    {"color": "rgb(255, 180, 76)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-// Trait
-assert-css: (
-    ".sidebar .block.trait a",
-    {"color": "rgb(83, 177, 219)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-move-cursor-to: ".sidebar .block.trait a"
-assert-css: (
-    ".sidebar .block.trait a:hover",
-    {"color": "rgb(255, 180, 76)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-// Function
-assert-css: (
-    ".sidebar .block.fn a",
-    {"color": "rgb(83, 177, 219)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-move-cursor-to: ".sidebar .block.fn a"
-assert-css: (
-    ".sidebar .block.fn a:hover",
-    {"color": "rgb(255, 180, 76)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-// Type definition
-assert-css: (
-    ".sidebar .block.type a",
-    {"color": "rgb(83, 177, 219)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-move-cursor-to: ".sidebar .block.type a"
-assert-css: (
-    ".sidebar .block.type a:hover",
-    {"color": "rgb(255, 180, 76)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-// Keyword
-assert-css: (
-    ".sidebar .block.keyword a",
-    {"color": "rgb(83, 177, 219)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-move-cursor-to: ".sidebar .block.keyword a"
-assert-css: (
-    ".sidebar .block.keyword a:hover",
-    {"color": "rgb(255, 180, 76)", "background-color": "rgba(0, 0, 0, 0)"},
+define-function: (
+    "check-colors",
+    (
+        theme, struct, struct_hover, struct_hover_background, enum, enum_hover,
+        enum_hover_background, union, union_hover, union_hover_background, trait, trait_hover,
+        trait_hover_background, fn, fn_hover, fn_hover_background, type, type_hover,
+        type_hover_background, keyword, keyword_hover, keyword_hover_background,
+    ),
+    [
+        ("local-storage", { "rustdoc-theme": |theme|, "rustdoc-use-system-theme": "false" }),
+        ("reload"),
+        // Struct
+        ("assert-css", (
+            ".sidebar .block.struct a:not(.current)",
+            {"color": |struct|, "background-color": "rgba(0, 0, 0, 0)"},
+        )),
+        ("move-cursor-to", ".sidebar .block.struct a:not(.current)"),
+        ("assert-css", (
+            ".sidebar .block.struct a:hover",
+            {"color": |struct_hover|, "background-color": |struct_hover_background|},
+        )),
+        // Enum
+        ("assert-css", (
+            ".sidebar .block.enum a",
+            {"color": |enum|, "background-color": "rgba(0, 0, 0, 0)"},
+        )),
+        ("move-cursor-to", ".sidebar .block.enum a"),
+        ("assert-css", (
+            ".sidebar .block.enum a:hover",
+            {"color": |enum_hover|, "background-color": |enum_hover_background|},
+        )),
+        // Union
+        ("assert-css", (
+            ".sidebar .block.union a",
+            {"color": |union|, "background-color": "rgba(0, 0, 0, 0)"},
+        )),
+        ("move-cursor-to", ".sidebar .block.union a"),
+        ("assert-css", (
+            ".sidebar .block.union a:hover",
+            {"color": |union_hover|, "background-color": |union_hover_background|},
+        )),
+        // Trait
+        ("assert-css", (
+            ".sidebar .block.trait a",
+            {"color": |trait|, "background-color": "rgba(0, 0, 0, 0)"},
+        )),
+        ("move-cursor-to", ".sidebar .block.trait a"),
+        ("assert-css", (
+            ".sidebar .block.trait a:hover",
+            {"color": |trait_hover|, "background-color": |trait_hover_background|},
+        )),
+        // Function
+        ("assert-css", (
+            ".sidebar .block.fn a",
+            {"color": |fn|, "background-color": "rgba(0, 0, 0, 0)"},
+        )),
+        ("move-cursor-to", ".sidebar .block.fn a"),
+        ("assert-css", (
+            ".sidebar .block.fn a:hover",
+            {"color": |fn_hover|, "background-color": |fn_hover_background|},
+        )),
+        // Type definition
+        ("assert-css", (
+            ".sidebar .block.type a",
+            {"color": |type|, "background-color": "rgba(0, 0, 0, 0)"},
+        )),
+        ("move-cursor-to", ".sidebar .block.type a"),
+        ("assert-css", (
+            ".sidebar .block.type a:hover",
+            {"color": |type_hover|, "background-color": |type_hover_background|},
+        )),
+        // Keyword
+        ("assert-css", (
+            ".sidebar .block.keyword a",
+            {"color": |keyword|, "background-color": "rgba(0, 0, 0, 0)"},
+        )),
+        ("move-cursor-to", ".sidebar .block.keyword a"),
+        ("assert-css", (
+            ".sidebar .block.keyword a:hover",
+            {"color": |keyword_hover|, "background-color": |keyword_hover_background|},
+        )),
+    ]
 )
 
-// Dark theme
-local-storage: {"rustdoc-theme": "dark"}
-reload:
-
-// Struct
-assert-css: (
-    ".sidebar .block.struct a:not(.current)",
-    {"color": "rgb(253, 191, 53)", "background-color": "rgba(0, 0, 0, 0)"},
+call-function: (
+    "check-colors",
+    {
+        "theme": "ayu",
+        "struct": "rgb(83, 177, 219)",
+        "struct_hover": "rgb(255, 180, 76)",
+        "struct_hover_background": "rgba(0, 0, 0, 0)",
+        "enum": "rgb(83, 177, 219)",
+        "enum_hover": "rgb(255, 180, 76)",
+        "enum_hover_background": "rgba(0, 0, 0, 0)",
+        "union": "rgb(83, 177, 219)",
+        "union_hover": "rgb(255, 180, 76)",
+        "union_hover_background": "rgba(0, 0, 0, 0)",
+        "trait": "rgb(83, 177, 219)",
+        "trait_hover": "rgb(255, 180, 76)",
+        "trait_hover_background": "rgba(0, 0, 0, 0)",
+        "fn": "rgb(83, 177, 219)",
+        "fn_hover": "rgb(255, 180, 76)",
+        "fn_hover_background": "rgba(0, 0, 0, 0)",
+        "type": "rgb(83, 177, 219)",
+        "type_hover": "rgb(255, 180, 76)",
+        "type_hover_background": "rgba(0, 0, 0, 0)",
+        "keyword": "rgb(83, 177, 219)",
+        "keyword_hover": "rgb(255, 180, 76)",
+        "keyword_hover_background": "rgba(0, 0, 0, 0)",
+    }
 )
-move-cursor-to: ".sidebar .block.struct a:not(.current)"
-assert-css: (
-    ".sidebar .block.struct a:hover",
-    {"color": "rgb(253, 191, 53)", "background-color": "rgb(68, 68, 68)"},
+call-function: (
+    "check-colors",
+    {
+        "theme": "dark",
+        "struct": "rgb(253, 191, 53)",
+        "struct_hover": "rgb(253, 191, 53)",
+        "struct_hover_background": "rgb(68, 68, 68)",
+        "enum": "rgb(253, 191, 53)",
+        "enum_hover": "rgb(253, 191, 53)",
+        "enum_hover_background": "rgb(68, 68, 68)",
+        "union": "rgb(253, 191, 53)",
+        "union_hover": "rgb(253, 191, 53)",
+        "union_hover_background": "rgb(68, 68, 68)",
+        "trait": "rgb(253, 191, 53)",
+        "trait_hover": "rgb(253, 191, 53)",
+        "trait_hover_background": "rgb(68, 68, 68)",
+        "fn": "rgb(253, 191, 53)",
+        "fn_hover": "rgb(253, 191, 53)",
+        "fn_hover_background": "rgb(68, 68, 68)",
+        "type": "rgb(253, 191, 53)",
+        "type_hover": "rgb(253, 191, 53)",
+        "type_hover_background": "rgb(68, 68, 68)",
+        "keyword": "rgb(253, 191, 53)",
+        "keyword_hover": "rgb(253, 191, 53)",
+        "keyword_hover_background": "rgb(68, 68, 68)",
+    }
 )
-// Enum
-assert-css: (
-    ".sidebar .block.enum a",
-    {"color": "rgb(253, 191, 53)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-move-cursor-to: ".sidebar .block.enum a"
-assert-css: (
-    ".sidebar .block.enum a:hover",
-    {"color": "rgb(253, 191, 53)", "background-color": "rgb(68, 68, 68)"},
-)
-// Union
-assert-css: (
-    ".sidebar .block.union a",
-    {"color": "rgb(253, 191, 53)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-move-cursor-to: ".sidebar .block.union a"
-assert-css: (
-    ".sidebar .block.union a:hover",
-    {"color": "rgb(253, 191, 53)", "background-color": "rgb(68, 68, 68)"},
-)
-// Trait
-assert-css: (
-    ".sidebar .block.trait a",
-    {"color": "rgb(253, 191, 53)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-move-cursor-to: ".sidebar .block.trait a"
-assert-css: (
-    ".sidebar .block.trait a:hover",
-    {"color": "rgb(253, 191, 53)", "background-color": "rgb(68, 68, 68)"},
-)
-// Function
-assert-css: (
-    ".sidebar .block.fn a",
-    {"color": "rgb(253, 191, 53)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-move-cursor-to: ".sidebar .block.fn a"
-assert-css: (
-    ".sidebar .block.fn a:hover",
-    {"color": "rgb(253, 191, 53)", "background-color": "rgb(68, 68, 68)"},
-)
-// Type definition
-assert-css: (
-    ".sidebar .block.type a",
-    {"color": "rgb(253, 191, 53)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-move-cursor-to: ".sidebar .block.type a"
-assert-css: (
-    ".sidebar .block.type a:hover",
-    {"color": "rgb(253, 191, 53)", "background-color": "rgb(68, 68, 68)"},
-)
-// Keyword
-assert-css: (
-    ".sidebar .block.keyword a",
-    {"color": "rgb(253, 191, 53)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-move-cursor-to: ".sidebar .block.keyword a"
-assert-css: (
-    ".sidebar .block.keyword a:hover",
-    {"color": "rgb(253, 191, 53)", "background-color": "rgb(68, 68, 68)"},
-)
-
-// Light theme
-local-storage: {"rustdoc-theme": "light"}
-reload:
-
-// Struct
-assert-css: (
-    ".sidebar .block.struct a:not(.current)",
-    {"color": "rgb(53, 109, 164)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-move-cursor-to: ".sidebar .block.struct a:not(.current)"
-assert-css: (
-    ".sidebar .block.struct a:hover",
-    {"color": "rgb(53, 109, 164)", "background-color": "rgb(255, 255, 255)"},
-)
-// Enum
-assert-css: (
-    ".sidebar .block.enum a",
-    {"color": "rgb(53, 109, 164)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-move-cursor-to: ".sidebar .block.enum a"
-assert-css: (
-    ".sidebar .block.enum a:hover",
-    {"color": "rgb(53, 109, 164)", "background-color": "rgb(255, 255, 255)"},
-)
-// Union
-assert-css: (
-    ".sidebar .block.union a",
-    {"color": "rgb(53, 109, 164)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-move-cursor-to: ".sidebar .block.union a"
-assert-css: (
-    ".sidebar .block.union a:hover",
-    {"color": "rgb(53, 109, 164)", "background-color": "rgb(255, 255, 255)"},
-)
-// Trait
-assert-css: (
-    ".sidebar .block.trait a",
-    {"color": "rgb(53, 109, 164)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-move-cursor-to: ".sidebar .block.trait a"
-assert-css: (
-    ".sidebar .block.trait a:hover",
-    {"color": "rgb(53, 109, 164)", "background-color": "rgb(255, 255, 255)"},
-)
-// Function
-assert-css: (
-    ".sidebar .block.fn a",
-    {"color": "rgb(53, 109, 164)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-move-cursor-to: ".sidebar .block.fn a"
-assert-css: (
-    ".sidebar .block.fn a:hover",
-    {"color": "rgb(53, 109, 164)", "background-color": "rgb(255, 255, 255)"},
-)
-// Type definition
-assert-css: (
-    ".sidebar .block.type a",
-    {"color": "rgb(53, 109, 164)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-move-cursor-to: ".sidebar .block.type a"
-assert-css: (
-    ".sidebar .block.type a:hover",
-    {"color": "rgb(53, 109, 164)", "background-color": "rgb(255, 255, 255)"},
-)
-// Keyword
-assert-css: (
-    ".sidebar .block.keyword a",
-    {"color": "rgb(53, 109, 164)", "background-color": "rgba(0, 0, 0, 0)"},
-)
-move-cursor-to: ".sidebar .block.keyword a"
-assert-css: (
-    ".sidebar .block.keyword a:hover",
-    {"color": "rgb(53, 109, 164)", "background-color": "rgb(255, 255, 255)"},
+call-function: (
+    "check-colors",
+    {
+        "theme": "light",
+        "struct": "rgb(53, 109, 164)",
+        "struct_hover": "rgb(53, 109, 164)",
+        "struct_hover_background": "rgb(255, 255, 255)",
+        "enum": "rgb(53, 109, 164)",
+        "enum_hover": "rgb(53, 109, 164)",
+        "enum_hover_background": "rgb(255, 255, 255)",
+        "union": "rgb(53, 109, 164)",
+        "union_hover": "rgb(53, 109, 164)",
+        "union_hover_background": "rgb(255, 255, 255)",
+        "trait": "rgb(53, 109, 164)",
+        "trait_hover": "rgb(53, 109, 164)",
+        "trait_hover_background": "rgb(255, 255, 255)",
+        "fn": "rgb(53, 109, 164)",
+        "fn_hover": "rgb(53, 109, 164)",
+        "fn_hover_background": "rgb(255, 255, 255)",
+        "type": "rgb(53, 109, 164)",
+        "type_hover": "rgb(53, 109, 164)",
+        "type_hover_background": "rgb(255, 255, 255)",
+        "keyword": "rgb(53, 109, 164)",
+        "keyword_hover": "rgb(53, 109, 164)",
+        "keyword_hover_background": "rgb(255, 255, 255)",
+    }
 )
diff --git a/src/test/rustdoc-gui/sidebar-source-code-display.goml b/src/test/rustdoc-gui/sidebar-source-code-display.goml
index 548fd22dcea9..4155dab64eb9 100644
--- a/src/test/rustdoc-gui/sidebar-source-code-display.goml
+++ b/src/test/rustdoc-gui/sidebar-source-code-display.goml
@@ -3,7 +3,7 @@ javascript: false
 goto: "file://" + |DOC_PATH| + "/src/test_docs/lib.rs.html"
 // Since the javascript is disabled, there shouldn't be a toggle.
 assert-false: "#sidebar-toggle"
-wait-for-css: (".sidebar > *", {"visibility": "hidden"})
+wait-for-css: (".sidebar", {"display": "none"})
 
 // Let's retry with javascript enabled.
 javascript: true
diff --git a/src/test/rustdoc-gui/sidebar-source-code.goml b/src/test/rustdoc-gui/sidebar-source-code.goml
index 9ba663687729..e9a987d52bbd 100644
--- a/src/test/rustdoc-gui/sidebar-source-code.goml
+++ b/src/test/rustdoc-gui/sidebar-source-code.goml
@@ -28,7 +28,7 @@ assert: "//*[@class='dir-entry' and @open]/*[text()='sub_mod']"
 // Only "another_folder" should be "open" in "lib2".
 assert: "//*[@class='dir-entry' and not(@open)]/*[text()='another_mod']"
 // All other trees should be collapsed.
-assert-count: ("//*[@id='source-sidebar']/details[not(text()='lib2') and not(@open)]", 5)
+assert-count: ("//*[@id='source-sidebar']/details[not(text()='lib2') and not(@open)]", 6)
 
 // We now switch to mobile mode.
 size: (600, 600)
diff --git a/src/test/rustdoc-gui/source-code-page.goml b/src/test/rustdoc-gui/source-code-page.goml
index 29d65fc7ebc7..b3b837ad377c 100644
--- a/src/test/rustdoc-gui/source-code-page.goml
+++ b/src/test/rustdoc-gui/source-code-page.goml
@@ -1,30 +1,96 @@
 // Checks that the interactions with the source code pages are working as expected.
 goto: "file://" + |DOC_PATH| + "/src/test_docs/lib.rs.html"
+show-text: true
 // Check that we can click on the line number.
-click: ".src-line-numbers > span:nth-child(4)" // This is the span for line 4.
+click: ".src-line-numbers > a:nth-child(4)" // This is the anchor for line 4.
 // Ensure that the page URL was updated.
 assert-document-property: ({"URL": "lib.rs.html#4"}, ENDS_WITH)
 assert-attribute: ("//*[@id='4']", {"class": "line-highlighted"})
-// We now check that the good spans are highlighted
+// Ensure that the default style, with the right border, isn't used.
+assert-css: ("//*[@id='4']", {"border-right-width": "0px"})
+reload:
+assert-attribute: ("//*[@id='4']", {"class": "line-highlighted"})
+assert-css: ("//*[@id='4']", {"border-right-width": "0px"})
+// We now check that the good anchors are highlighted
 goto: "file://" + |DOC_PATH| + "/src/test_docs/lib.rs.html#4-6"
-assert-attribute-false: (".src-line-numbers > span:nth-child(3)", {"class": "line-highlighted"})
-assert-attribute: (".src-line-numbers > span:nth-child(4)", {"class": "line-highlighted"})
-assert-attribute: (".src-line-numbers > span:nth-child(5)", {"class": "line-highlighted"})
-assert-attribute: (".src-line-numbers > span:nth-child(6)", {"class": "line-highlighted"})
-assert-attribute-false: (".src-line-numbers > span:nth-child(7)", {"class": "line-highlighted"})
+assert-attribute-false: (".src-line-numbers > a:nth-child(3)", {"class": "line-highlighted"})
+assert-attribute: (".src-line-numbers > a:nth-child(4)", {"class": "line-highlighted"})
+assert-attribute: (".src-line-numbers > a:nth-child(5)", {"class": "line-highlighted"})
+assert-attribute: (".src-line-numbers > a:nth-child(6)", {"class": "line-highlighted"})
+assert-attribute-false: (".src-line-numbers > a:nth-child(7)", {"class": "line-highlighted"})
+
+define-function: (
+    "check-colors",
+    (theme, color, background_color, highlight_color, highlight_background_color),
+    [
+        ("local-storage", {"rustdoc-theme": |theme|, "rustdoc-use-system-theme": "false"}),
+        ("reload"),
+        ("assert-css", (
+            ".src-line-numbers > a:not(.line-highlighted)",
+            {"color": |color|, "background-color": |background_color|},
+            ALL,
+        )),
+        ("assert-css", (
+            ".src-line-numbers > a.line-highlighted",
+            {"color": |highlight_color|, "background-color": |highlight_background_color|},
+            ALL,
+        )),
+    ],
+)
+
+call-function: ("check-colors", {
+    "theme": "ayu",
+    "color": "rgb(92, 103, 115)",
+    "background_color": "rgba(0, 0, 0, 0)",
+    "highlight_color": "rgb(112, 128, 144)",
+    "highlight_background_color": "rgba(255, 236, 164, 0.06)",
+})
+call-function: ("check-colors", {
+    "theme": "dark",
+    "color": "rgb(59, 145, 226)",
+    "background_color": "rgba(0, 0, 0, 0)",
+    "highlight_color": "rgb(59, 145, 226)",
+    "highlight_background_color": "rgb(10, 4, 47)",
+})
+call-function: ("check-colors", {
+    "theme": "light",
+    "color": "rgb(198, 126, 45)",
+    "background_color": "rgba(0, 0, 0, 0)",
+    "highlight_color": "rgb(198, 126, 45)",
+    "highlight_background_color": "rgb(253, 255, 211)",
+})
+
 // This is to ensure that the content is correctly align with the line numbers.
 compare-elements-position: ("//*[@id='1']", ".rust > code > span", ("y"))
+// Check the `href` property so that users can treat anchors as links.
+assert-property: (".src-line-numbers > a:nth-child(1)", {
+    "href": "file://" + |DOC_PATH| + "/src/test_docs/lib.rs.html#1"
+})
+assert-property: (".src-line-numbers > a:nth-child(2)", {
+    "href": "file://" + |DOC_PATH| + "/src/test_docs/lib.rs.html#2"
+})
+assert-property: (".src-line-numbers > a:nth-child(3)", {
+    "href": "file://" + |DOC_PATH| + "/src/test_docs/lib.rs.html#3"
+})
+assert-property: (".src-line-numbers > a:nth-child(4)", {
+    "href": "file://" + |DOC_PATH| + "/src/test_docs/lib.rs.html#4"
+})
+assert-property: (".src-line-numbers > a:nth-child(5)", {
+    "href": "file://" + |DOC_PATH| + "/src/test_docs/lib.rs.html#5"
+})
+assert-property: (".src-line-numbers > a:nth-child(6)", {
+    "href": "file://" + |DOC_PATH| + "/src/test_docs/lib.rs.html#6"
+})
 
 // Assert that the line numbers text is aligned to the right.
 assert-css: (".src-line-numbers", {"text-align": "right"})
 
 // Now let's check that clicking on something else than the line number doesn't
 // do anything (and certainly not add a `#NaN` to the URL!).
-show-text: true
 goto: "file://" + |DOC_PATH| + "/src/test_docs/lib.rs.html"
 // We use this assert-position to know where we will click.
 assert-position: ("//*[@id='1']", {"x": 104, "y": 112})
-// We click on the left of the "1" span but still in the "src-line-number" `<pre>`.
+// We click on the left of the "1" anchor but still in the "src-line-number" `<pre>`.
 click: (103, 103)
 assert-document-property: ({"URL": "/lib.rs.html"}, ENDS_WITH)
 
@@ -36,7 +102,7 @@ assert: ".source-sidebar-expanded"
 
 // We check that the first entry of the sidebar is collapsed
 assert-property: ("#source-sidebar details:first-of-type", {"open": "false"})
-assert-text: ("#source-sidebar details:first-of-type > summary", "implementors")
+assert-text: ("#source-sidebar details:first-of-type > summary", "huge_logo")
 // We now click on it.
 click: "#source-sidebar details:first-of-type > summary"
 assert-property: ("#source-sidebar details:first-of-type", {"open": "true"})
diff --git a/src/test/rustdoc-gui/src-font-size.goml b/src/test/rustdoc-gui/src-font-size.goml
index b17dfd94cf0e..9233f37444b6 100644
--- a/src/test/rustdoc-gui/src-font-size.goml
+++ b/src/test/rustdoc-gui/src-font-size.goml
@@ -9,3 +9,8 @@ assert-css: (".impl.has-srclink .code-header", {"font-size": "18px", "font-weigh
 // Check the impl items.
 assert-css: (".impl-items .has-srclink .srclink", {"font-size": "16px", "font-weight": 400}, ALL)
 assert-css: (".impl-items .has-srclink .code-header", {"font-size": "16px", "font-weight": 600}, ALL)
+
+// Check that we can click on source link
+store-document-property: (url, "URL")
+click: ".impl-items .has-srclink .srclink"
+assert-document-property-false: {"URL": |url|}
diff --git a/src/test/rustdoc-gui/src/huge_logo/Cargo.lock b/src/test/rustdoc-gui/src/huge_logo/Cargo.lock
new file mode 100644
index 000000000000..142805750642
--- /dev/null
+++ b/src/test/rustdoc-gui/src/huge_logo/Cargo.lock
@@ -0,0 +1,7 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "huge_logo"
+version = "0.1.0"
diff --git a/src/test/rustdoc-gui/src/huge_logo/Cargo.toml b/src/test/rustdoc-gui/src/huge_logo/Cargo.toml
new file mode 100644
index 000000000000..3f10d09c80ad
--- /dev/null
+++ b/src/test/rustdoc-gui/src/huge_logo/Cargo.toml
@@ -0,0 +1,8 @@
+[package]
+name = "huge_logo"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
diff --git a/src/test/rustdoc-gui/src/huge_logo/src/lib.rs b/src/test/rustdoc-gui/src/huge_logo/src/lib.rs
new file mode 100644
index 000000000000..ec137fb9a88f
--- /dev/null
+++ b/src/test/rustdoc-gui/src/huge_logo/src/lib.rs
@@ -0,0 +1,17 @@
+// ignore-tidy-linelength
+#![doc(html_logo_url = "data:image/png;base64,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")]
+
+pub fn add(left: usize, right: usize) -> usize {
+    left + right
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn it_works() {
+        let result = add(2, 2);
+        assert_eq!(result, 4);
+    }
+}
diff --git a/src/test/rustdoc-gui/src/test_docs/lib.rs b/src/test/rustdoc-gui/src/test_docs/lib.rs
index fdf97e492aa2..8eea5ad01c02 100644
--- a/src/test/rustdoc-gui/src/test_docs/lib.rs
+++ b/src/test/rustdoc-gui/src/test_docs/lib.rs
@@ -416,3 +416,20 @@ pub trait TraitWithoutGenerics {
 
     fn foo();
 }
+
+pub mod trait_members {
+    pub trait TraitMembers {
+        /// Some type
+        type Type;
+        /// Some function
+        fn function();
+        /// Some other function
+        fn function2();
+    }
+    pub struct HasTrait;
+    impl TraitMembers for HasTrait {
+        type Type = u8;
+        fn function() {}
+        fn function2() {}
+    }
+}
diff --git a/src/test/rustdoc-gui/target.goml b/src/test/rustdoc-gui/target.goml
new file mode 100644
index 000000000000..3e5c30dc7eaf
--- /dev/null
+++ b/src/test/rustdoc-gui/target.goml
@@ -0,0 +1,35 @@
+// Check that the targetted element has the expected styles.
+goto: "file://" + |DOC_PATH| + "/lib2/struct.Foo.html#method.a_method"
+show-text: true
+
+// Confirming that the method is the target.
+assert: "#method\.a_method:target"
+
+define-function: (
+    "check-style",
+    (theme, background, border),
+    [
+        ("local-storage", {"rustdoc-theme": |theme|, "rustdoc-use-system-theme": "false"}),
+        ("reload"),
+        ("assert-css", ("#method\.a_method:target", {
+            "background-color": |background|,
+            "border-right": "3px solid " + |border|,
+        })),
+    ],
+)
+
+call-function: ("check-style", {
+    "theme": "ayu",
+    "background": "rgba(255, 236, 164, 0.06)",
+    "border": "rgba(255, 180, 76, 0.85)",
+})
+call-function: ("check-style", {
+    "theme": "dark",
+    "background": "rgb(73, 74, 61)",
+    "border": "rgb(187, 116, 16)",
+})
+call-function: ("check-style", {
+    "theme": "light",
+    "background": "rgb(253, 255, 211)",
+    "border": "rgb(173, 124, 55)",
+})
diff --git a/src/test/rustdoc-gui/theme-in-history.goml b/src/test/rustdoc-gui/theme-in-history.goml
index c29571728a1a..10508e86a36e 100644
--- a/src/test/rustdoc-gui/theme-in-history.goml
+++ b/src/test/rustdoc-gui/theme-in-history.goml
@@ -3,7 +3,6 @@ goto: "file://" + |DOC_PATH| + "/test_docs/index.html"
 // Set the theme to dark.
 local-storage: {
     "rustdoc-theme": "dark",
-    "rustdoc-preferred-dark-theme": "dark",
     "rustdoc-use-system-theme": "false",
 }
 // We reload the page so the local storage settings are being used.
diff --git a/src/test/rustdoc-gui/trait-sidebar-item-order.goml b/src/test/rustdoc-gui/trait-sidebar-item-order.goml
index a799444a1087..e5d023544d68 100644
--- a/src/test/rustdoc-gui/trait-sidebar-item-order.goml
+++ b/src/test/rustdoc-gui/trait-sidebar-item-order.goml
@@ -1,4 +1,9 @@
 // Checks that the elements in the sidebar are alphabetically sorted.
+
+// We need to disable this check because `implementors/test_docs/trait.AnotherOne.js`
+// doesn't exist.
+fail-on-request-error: false
+
 goto: "file://" + |DOC_PATH| + "/test_docs/trait.AnotherOne.html"
 assert-text: (".sidebar-elems section .block li:nth-of-type(1) > a", "another")
 assert-text: (".sidebar-elems section .block li:nth-of-type(2) > a", "func1")
diff --git a/src/test/rustdoc-gui/type-declation-overflow.goml b/src/test/rustdoc-gui/type-declation-overflow.goml
index fce3002e7508..dcffe956c219 100644
--- a/src/test/rustdoc-gui/type-declation-overflow.goml
+++ b/src/test/rustdoc-gui/type-declation-overflow.goml
@@ -1,4 +1,10 @@
 // This test ensures that the items declaration content overflow is handled inside the <pre> directly.
+
+// We need to disable this check because
+// `implementors/test_docs/trait.ALongNameBecauseItHelpsTestingTheCurrentProblem.js`
+// doesn't exist.
+fail-on-request-error: false
+
 goto: "file://" + |DOC_PATH| + "/lib2/long_trait/trait.ALongNameBecauseItHelpsTestingTheCurrentProblem.html"
 // We set a fixed size so there is no chance of "random" resize.
 size: (1100, 800)
diff --git a/src/test/rustdoc-js/reexport.js b/src/test/rustdoc-js/reexport.js
new file mode 100644
index 000000000000..871e75d9b2b3
--- /dev/null
+++ b/src/test/rustdoc-js/reexport.js
@@ -0,0 +1,17 @@
+// exact-check
+
+const QUERY = ['Subscriber', 'AnotherOne'];
+
+const EXPECTED = [
+    {
+        'others': [
+            { 'path': 'reexport::fmt', 'name': 'Subscriber' },
+            { 'path': 'reexport', 'name': 'FmtSubscriber' },
+        ],
+    },
+    {
+        'others': [
+            { 'path': 'reexport', 'name': 'AnotherOne' },
+        ],
+    },
+];
diff --git a/src/test/rustdoc-js/reexport.rs b/src/test/rustdoc-js/reexport.rs
new file mode 100644
index 000000000000..d69b2901edd5
--- /dev/null
+++ b/src/test/rustdoc-js/reexport.rs
@@ -0,0 +1,11 @@
+// This test enforces that the (renamed) reexports are present in the search results.
+
+pub mod fmt {
+    pub struct Subscriber;
+}
+mod foo {
+    pub struct AnotherOne;
+}
+
+pub use foo::AnotherOne;
+pub use fmt::Subscriber as FmtSubscriber;
diff --git a/src/test/rustdoc-json/reexport/reexport_method_from_private_module.rs b/src/test/rustdoc-json/reexport/reexport_method_from_private_module.rs
new file mode 100644
index 000000000000..239b1a23b43d
--- /dev/null
+++ b/src/test/rustdoc-json/reexport/reexport_method_from_private_module.rs
@@ -0,0 +1,28 @@
+// Regression test for <https://github.com/rust-lang/rust/issues/102583>.
+
+// @set impl_S = "$.index[*][?(@.docs=='impl S')].id"
+// @has "$.index[*][?(@.name=='S')].inner.impls[*]" $impl_S
+// @set is_present = "$.index[*][?(@.name=='is_present')].id"
+// @is "$.index[*][?(@.docs=='impl S')].inner.items[*]" $is_present
+// @!has "$.index[*][?(@.name=='hidden_impl')]"
+// @!has "$.index[*][?(@.name=='hidden_fn')]"
+
+#![no_std]
+
+mod private_mod {
+    pub struct S;
+
+    /// impl S
+    impl S {
+        pub fn is_present() {}
+        #[doc(hidden)]
+        pub fn hidden_fn() {}
+    }
+
+    #[doc(hidden)]
+    impl S {
+        pub fn hidden_impl() {}
+    }
+}
+
+pub use private_mod::*;
diff --git a/src/test/rustdoc-ui/ambiguous-inherent-assoc-ty.rs b/src/test/rustdoc-ui/ambiguous-inherent-assoc-ty.rs
index e58bba640585..94ea0e93bf63 100644
--- a/src/test/rustdoc-ui/ambiguous-inherent-assoc-ty.rs
+++ b/src/test/rustdoc-ui/ambiguous-inherent-assoc-ty.rs
@@ -1,3 +1,4 @@
+// check-pass
 // This test ensures that rustdoc does not panic on inherented associated types
 // that are referred to without fully-qualified syntax.
 
@@ -9,8 +10,4 @@ pub struct Struct;
 impl Struct {
     pub type AssocTy = usize;
     pub const AssocConst: Self::AssocTy = 42;
-    //~^ ERROR ambiguous associated type
-    //~| HELP use fully-qualified syntax
-    //~| ERROR ambiguous associated type
-    //~| HELP use fully-qualified syntax
 }
diff --git a/src/test/rustdoc-ui/ambiguous-inherent-assoc-ty.stderr b/src/test/rustdoc-ui/ambiguous-inherent-assoc-ty.stderr
deleted file mode 100644
index b963b722f662..000000000000
--- a/src/test/rustdoc-ui/ambiguous-inherent-assoc-ty.stderr
+++ /dev/null
@@ -1,15 +0,0 @@
-error[E0223]: ambiguous associated type
-  --> $DIR/ambiguous-inherent-assoc-ty.rs:11:27
-   |
-LL |     pub const AssocConst: Self::AssocTy = 42;
-   |                           ^^^^^^^^^^^^^ help: use fully-qualified syntax: `<Struct as Trait>::AssocTy`
-
-error[E0223]: ambiguous associated type
-  --> $DIR/ambiguous-inherent-assoc-ty.rs:11:27
-   |
-LL |     pub const AssocConst: Self::AssocTy = 42;
-   |                           ^^^^^^^^^^^^^ help: use fully-qualified syntax: `<Struct as Trait>::AssocTy`
-
-error: aborting due to 2 previous errors
-
-For more information about this error, try `rustc --explain E0223`.
diff --git a/src/test/rustdoc-ui/intra-doc/unknown-disambiguator.stderr b/src/test/rustdoc-ui/intra-doc/unknown-disambiguator.stderr
index e7b4c43e790e..19e541736bd0 100644
--- a/src/test/rustdoc-ui/intra-doc/unknown-disambiguator.stderr
+++ b/src/test/rustdoc-ui/intra-doc/unknown-disambiguator.stderr
@@ -4,7 +4,7 @@ error: unknown disambiguator `foo`
 LL | //! Linking to [foo@banana] and [`bar@banana!()`].
    |                 ^^^
    |
-   = note: see https://doc.rust-lang.org/$CHANNEL/rustdoc/linking-to-items-by-name.html#namespaces-and-disambiguators for more info about disambiguators
+   = note: see https://doc.rust-lang.org/$CHANNEL/rustdoc/write-documentation/linking-to-items-by-name.html#namespaces-and-disambiguators for more info about disambiguators
 note: the lint level is defined here
   --> $DIR/unknown-disambiguator.rs:2:9
    |
@@ -18,7 +18,7 @@ error: unknown disambiguator `bar`
 LL | //! Linking to [foo@banana] and [`bar@banana!()`].
    |                                   ^^^
    |
-   = note: see https://doc.rust-lang.org/$CHANNEL/rustdoc/linking-to-items-by-name.html#namespaces-and-disambiguators for more info about disambiguators
+   = note: see https://doc.rust-lang.org/$CHANNEL/rustdoc/write-documentation/linking-to-items-by-name.html#namespaces-and-disambiguators for more info about disambiguators
 
 error: unknown disambiguator `foo`
   --> $DIR/unknown-disambiguator.rs:10:34
@@ -26,7 +26,7 @@ error: unknown disambiguator `foo`
 LL | //! And with weird backticks: [``foo@hello``] [foo`@`hello].
    |                                  ^^^
    |
-   = note: see https://doc.rust-lang.org/$CHANNEL/rustdoc/linking-to-items-by-name.html#namespaces-and-disambiguators for more info about disambiguators
+   = note: see https://doc.rust-lang.org/$CHANNEL/rustdoc/write-documentation/linking-to-items-by-name.html#namespaces-and-disambiguators for more info about disambiguators
 
 error: unknown disambiguator `foo`
   --> $DIR/unknown-disambiguator.rs:10:48
@@ -34,7 +34,7 @@ error: unknown disambiguator `foo`
 LL | //! And with weird backticks: [``foo@hello``] [foo`@`hello].
    |                                                ^^^
    |
-   = note: see https://doc.rust-lang.org/$CHANNEL/rustdoc/linking-to-items-by-name.html#namespaces-and-disambiguators for more info about disambiguators
+   = note: see https://doc.rust-lang.org/$CHANNEL/rustdoc/write-documentation/linking-to-items-by-name.html#namespaces-and-disambiguators for more info about disambiguators
 
 error: unknown disambiguator ``
   --> $DIR/unknown-disambiguator.rs:7:31
@@ -42,7 +42,7 @@ error: unknown disambiguator ``
 LL | //! And to [no disambiguator](@nectarine) and [another](@apricot!()).
    |                               ^
    |
-   = note: see https://doc.rust-lang.org/$CHANNEL/rustdoc/linking-to-items-by-name.html#namespaces-and-disambiguators for more info about disambiguators
+   = note: see https://doc.rust-lang.org/$CHANNEL/rustdoc/write-documentation/linking-to-items-by-name.html#namespaces-and-disambiguators for more info about disambiguators
 
 error: unknown disambiguator ``
   --> $DIR/unknown-disambiguator.rs:7:57
@@ -50,7 +50,7 @@ error: unknown disambiguator ``
 LL | //! And to [no disambiguator](@nectarine) and [another](@apricot!()).
    |                                                         ^
    |
-   = note: see https://doc.rust-lang.org/$CHANNEL/rustdoc/linking-to-items-by-name.html#namespaces-and-disambiguators for more info about disambiguators
+   = note: see https://doc.rust-lang.org/$CHANNEL/rustdoc/write-documentation/linking-to-items-by-name.html#namespaces-and-disambiguators for more info about disambiguators
 
 error: aborting due to 6 previous errors
 
diff --git a/src/test/rustdoc-ui/invalid-html-self-closing-tag.rs b/src/test/rustdoc-ui/invalid-html-self-closing-tag.rs
new file mode 100644
index 000000000000..d973a53cbc7c
--- /dev/null
+++ b/src/test/rustdoc-ui/invalid-html-self-closing-tag.rs
@@ -0,0 +1,70 @@
+#![deny(rustdoc::invalid_html_tags)]
+
+/// <p/>
+//~^ ERROR invalid self-closing HTML tag `p`
+pub struct A;
+
+/// <p style/>
+//~^ ERROR invalid self-closing HTML tag `p`
+pub struct B;
+
+/// <p style=""/>
+//~^ ERROR invalid self-closing HTML tag `p`
+pub struct C;
+
+/// <p style="x"/>
+//~^ ERROR invalid self-closing HTML tag `p`
+pub struct D;
+
+/// <p style="x/></p>
+//~^ ERROR unclosed quoted HTML attribute
+pub struct E;
+
+/// <p style='x/></p>
+//~^ ERROR unclosed quoted HTML attribute
+pub struct F;
+
+/// <p style="x/"></p>
+pub struct G;
+
+/// <p style="x/"/>
+//~^ ERROR invalid self-closing HTML tag `p`
+pub struct H;
+
+/// <p / >
+//~^ ERROR invalid self-closing HTML tag `p`
+pub struct I;
+
+/// <br/>
+pub struct J;
+
+/// <a href=/></a>
+pub struct K;
+
+/// <a href=//></a>
+pub struct L;
+
+/// <a href="/"/>
+//~^ ERROR invalid self-closing HTML tag `a`
+pub struct M;
+
+/// <a href=x />
+//~^ ERROR invalid self-closing HTML tag `a`
+pub struct N;
+
+/// <a href= />
+//~^ ERROR invalid self-closing HTML tag `a`
+pub struct O;
+
+/// <a href=x/></a>
+pub struct P;
+
+/// <svg><rect width=1 height=1 /></svg>
+pub struct Q;
+
+/// <svg><rect width=1 height=/></svg>
+//~^ ERROR unclosed HTML tag `rect`
+pub struct R;
+
+/// <svg / q>
+pub struct S;
diff --git a/src/test/rustdoc-ui/invalid-html-self-closing-tag.stderr b/src/test/rustdoc-ui/invalid-html-self-closing-tag.stderr
new file mode 100644
index 000000000000..e45edfb43ff8
--- /dev/null
+++ b/src/test/rustdoc-ui/invalid-html-self-closing-tag.stderr
@@ -0,0 +1,80 @@
+error: invalid self-closing HTML tag `p`
+  --> $DIR/invalid-html-self-closing-tag.rs:3:5
+   |
+LL | /// <p/>
+   |     ^^
+   |
+note: the lint level is defined here
+  --> $DIR/invalid-html-self-closing-tag.rs:1:9
+   |
+LL | #![deny(rustdoc::invalid_html_tags)]
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: invalid self-closing HTML tag `p`
+  --> $DIR/invalid-html-self-closing-tag.rs:7:5
+   |
+LL | /// <p style/>
+   |     ^^
+
+error: invalid self-closing HTML tag `p`
+  --> $DIR/invalid-html-self-closing-tag.rs:11:5
+   |
+LL | /// <p style=""/>
+   |     ^^
+
+error: invalid self-closing HTML tag `p`
+  --> $DIR/invalid-html-self-closing-tag.rs:15:5
+   |
+LL | /// <p style="x"/>
+   |     ^^
+
+error: unclosed quoted HTML attribute on tag `p`
+  --> $DIR/invalid-html-self-closing-tag.rs:19:14
+   |
+LL | /// <p style="x/></p>
+   |              ^
+
+error: unclosed quoted HTML attribute on tag `p`
+  --> $DIR/invalid-html-self-closing-tag.rs:23:14
+   |
+LL | /// <p style='x/></p>
+   |              ^
+
+error: invalid self-closing HTML tag `p`
+  --> $DIR/invalid-html-self-closing-tag.rs:30:5
+   |
+LL | /// <p style="x/"/>
+   |     ^^
+
+error: invalid self-closing HTML tag `p`
+  --> $DIR/invalid-html-self-closing-tag.rs:34:5
+   |
+LL | /// <p / >
+   |     ^^
+
+error: invalid self-closing HTML tag `a`
+  --> $DIR/invalid-html-self-closing-tag.rs:47:5
+   |
+LL | /// <a href="/"/>
+   |     ^^
+
+error: invalid self-closing HTML tag `a`
+  --> $DIR/invalid-html-self-closing-tag.rs:51:5
+   |
+LL | /// <a href=x />
+   |     ^^
+
+error: invalid self-closing HTML tag `a`
+  --> $DIR/invalid-html-self-closing-tag.rs:55:5
+   |
+LL | /// <a href= />
+   |     ^^
+
+error: unclosed HTML tag `rect`
+  --> $DIR/invalid-html-self-closing-tag.rs:65:10
+   |
+LL | /// <svg><rect width=1 height=/></svg>
+   |          ^^^^^
+
+error: aborting due to 12 previous errors
+
diff --git a/src/test/rustdoc-ui/issue-103997.rs b/src/test/rustdoc-ui/issue-103997.rs
new file mode 100644
index 000000000000..36f42fb15f7e
--- /dev/null
+++ b/src/test/rustdoc-ui/issue-103997.rs
@@ -0,0 +1,6 @@
+// check-pass
+
+pub fn foo() {}
+
+/// [`foo`](Self::foo) //~ WARNING unresolved link to `Self::foo`
+pub use foo as bar;
diff --git a/src/test/rustdoc-ui/issue-103997.stderr b/src/test/rustdoc-ui/issue-103997.stderr
new file mode 100644
index 000000000000..c06db91496f8
--- /dev/null
+++ b/src/test/rustdoc-ui/issue-103997.stderr
@@ -0,0 +1,10 @@
+warning: unresolved link to `Self::foo`
+  --> $DIR/issue-103997.rs:5:13
+   |
+LL | /// [`foo`](Self::foo)
+   |             ^^^^^^^^^ no item named `Self` in scope
+   |
+   = note: `#[warn(rustdoc::broken_intra_doc_links)]` on by default
+
+warning: 1 warning emitted
+
diff --git a/src/test/rustdoc-ui/track-diagnostics.rs b/src/test/rustdoc-ui/track-diagnostics.rs
new file mode 100644
index 000000000000..fcc50a7aba07
--- /dev/null
+++ b/src/test/rustdoc-ui/track-diagnostics.rs
@@ -0,0 +1,10 @@
+// compile-flags: -Z track-diagnostics
+// error-pattern: created at
+
+// Normalize the emitted location so this doesn't need
+// updating everytime someone adds or removes a line.
+// normalize-stderr-test ".rs:\d+:\d+" -> ".rs:LL:CC"
+
+struct A;
+struct B;
+const S: A = B;
diff --git a/src/test/rustdoc-ui/track-diagnostics.stderr b/src/test/rustdoc-ui/track-diagnostics.stderr
new file mode 100644
index 000000000000..ec3031862531
--- /dev/null
+++ b/src/test/rustdoc-ui/track-diagnostics.stderr
@@ -0,0 +1,10 @@
+error[E0308]: mismatched types
+  --> $DIR/track-diagnostics.rs:LL:CC
+   |
+LL | const S: A = B;
+   |              ^ expected struct `A`, found struct `B`
+-Ztrack-diagnostics: created at compiler/rustc_infer/src/infer/error_reporting/mod.rs:LL:CC
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/rustdoc-ui/z-help.stdout b/src/test/rustdoc-ui/z-help.stdout
index 46f11d2e5d1e..22e378213228 100644
--- a/src/test/rustdoc-ui/z-help.stdout
+++ b/src/test/rustdoc-ui/z-help.stdout
@@ -171,6 +171,7 @@
     -Z                             time-passes=val -- measure time of each rustc pass (default: no)
     -Z                               tls-model=val -- choose the TLS model to use (`rustc --print tls-models` for details)
     -Z                            trace-macros=val -- for every macro invocation, print its name and arguments (default: no)
+    -Z                       track-diagnostics=val -- tracks where in rustc a diagnostic was emitted
     -Z                translate-additional-ftl=val -- additional fluent translation to preferentially use (for testing translation)
     -Z        translate-directionality-markers=val -- emit directionality isolation markers in translated diagnostics
     -Z                          translate-lang=val -- language identifier for diagnostic output
diff --git a/src/test/rustdoc/assoc-consts.rs b/src/test/rustdoc/assoc-consts.rs
index a3e10ee5555a..3da19a13e533 100644
--- a/src/test/rustdoc/assoc-consts.rs
+++ b/src/test/rustdoc/assoc-consts.rs
@@ -46,6 +46,7 @@ pub fn f(_: &(ToString + 'static)) {}
 impl Bar {
     // @has assoc_consts/struct.Bar.html '//*[@id="associatedconstant.F"]' \
     //      "const F: fn(_: &(dyn ToString + 'static))"
+    // FIXME(fmease): Hide default lifetime, render "const F: fn(_: &dyn ToString)"
     pub const F: fn(_: &(ToString + 'static)) = f;
 }
 
diff --git a/src/test/rustdoc/async-trait-sig.rs b/src/test/rustdoc/async-trait-sig.rs
new file mode 100644
index 000000000000..2578bc8f7a16
--- /dev/null
+++ b/src/test/rustdoc/async-trait-sig.rs
@@ -0,0 +1,14 @@
+// edition:2021
+
+#![feature(async_fn_in_trait)]
+#![allow(incomplete_features)]
+
+pub trait Foo {
+    // @has async_trait_sig/trait.Foo.html '//h4[@class="code-header"]' "async fn bar() -> i32"
+    async fn bar() -> i32;
+
+    // @has async_trait_sig/trait.Foo.html '//h4[@class="code-header"]' "async fn baz() -> i32"
+    async fn baz() -> i32 {
+        1
+    }
+}
diff --git a/src/test/rustdoc/async-trait.rs b/src/test/rustdoc/async-trait.rs
new file mode 100644
index 000000000000..a473e467473e
--- /dev/null
+++ b/src/test/rustdoc/async-trait.rs
@@ -0,0 +1,16 @@
+// aux-build:async-trait-dep.rs
+// edition:2021
+
+#![feature(async_fn_in_trait)]
+#![allow(incomplete_features)]
+
+extern crate async_trait_dep;
+
+pub struct Oink {}
+
+// @has 'async_trait/struct.Oink.html' '//h4[@class="code-header"]' "async fn woof()"
+impl async_trait_dep::Meow for Oink {
+    async fn woof() {
+        todo!()
+    }
+}
diff --git a/src/test/rustdoc/auxiliary/async-trait-dep.rs b/src/test/rustdoc/auxiliary/async-trait-dep.rs
new file mode 100644
index 000000000000..10a55dd0260e
--- /dev/null
+++ b/src/test/rustdoc/auxiliary/async-trait-dep.rs
@@ -0,0 +1,9 @@
+// edition:2021
+
+#![feature(async_fn_in_trait)]
+#![allow(incomplete_features)]
+
+pub trait Meow {
+    /// Who's a good dog?
+    async fn woof();
+}
diff --git a/src/test/rustdoc/auxiliary/incoherent-impl-types.rs b/src/test/rustdoc/auxiliary/incoherent-impl-types.rs
new file mode 100644
index 000000000000..fc51e42e5004
--- /dev/null
+++ b/src/test/rustdoc/auxiliary/incoherent-impl-types.rs
@@ -0,0 +1,7 @@
+#![feature(rustc_attrs)]
+
+#[rustc_has_incoherent_inherent_impls]
+pub trait FooTrait {}
+
+#[rustc_has_incoherent_inherent_impls]
+pub struct FooStruct;
diff --git a/src/test/rustdoc/auxiliary/masked.rs b/src/test/rustdoc/auxiliary/masked.rs
index f289359e52ac..3d722d5e0c2e 100644
--- a/src/test/rustdoc/auxiliary/masked.rs
+++ b/src/test/rustdoc/auxiliary/masked.rs
@@ -8,3 +8,7 @@ pub trait MaskedTrait {
 impl MaskedTrait for String {
     fn masked_method() {}
 }
+
+pub trait MaskedBlanketTrait {}
+
+impl<T> MaskedBlanketTrait for T {}
diff --git a/src/test/rustdoc/auxiliary/reexport-doc-aux.rs b/src/test/rustdoc/auxiliary/reexport-doc-aux.rs
new file mode 100644
index 000000000000..3400717eba1e
--- /dev/null
+++ b/src/test/rustdoc/auxiliary/reexport-doc-aux.rs
@@ -0,0 +1,5 @@
+pub struct Foo;
+
+impl Foo {
+    pub fn foo() {}
+}
diff --git a/src/test/rustdoc/check-source-code-urls-to-def.rs b/src/test/rustdoc/check-source-code-urls-to-def.rs
index d00a3e355199..5959f9c7c599 100644
--- a/src/test/rustdoc/check-source-code-urls-to-def.rs
+++ b/src/test/rustdoc/check-source-code-urls-to-def.rs
@@ -10,14 +10,14 @@ extern crate source_code;
 
 // @has 'src/foo/check-source-code-urls-to-def.rs.html'
 
-// @has - '//a[@href="auxiliary/source-code-bar.rs.html#1-17"]' 'bar'
+// @has - '//pre[@class="rust"]//a[@href="auxiliary/source-code-bar.rs.html#1-17"]' 'bar'
 #[path = "auxiliary/source-code-bar.rs"]
 pub mod bar;
 
-// @count - '//a[@href="auxiliary/source-code-bar.rs.html#5"]' 4
+// @count - '//pre[@class="rust"]//a[@href="auxiliary/source-code-bar.rs.html#5"]' 4
 use bar::Bar;
-// @has - '//a[@href="auxiliary/source-code-bar.rs.html#13"]' 'self'
-// @has - '//a[@href="auxiliary/source-code-bar.rs.html#14"]' 'Trait'
+// @has - '//pre[@class="rust"]//a[@href="auxiliary/source-code-bar.rs.html#13"]' 'self'
+// @has - '//pre[@class="rust"]//a[@href="auxiliary/source-code-bar.rs.html#14"]' 'Trait'
 use bar::sub::{self, Trait};
 
 pub struct Foo;
@@ -28,29 +28,29 @@ impl Foo {
 
 fn babar() {}
 
-// @has - '//a/@href' '/struct.String.html'
-// @has - '//a/@href' '/primitive.u32.html'
-// @has - '//a/@href' '/primitive.str.html'
-// @count - '//a[@href="#23"]' 5
-// @has - '//a[@href="../../source_code/struct.SourceCode.html"]' 'source_code::SourceCode'
+// @has - '//pre[@class="rust"]//a/@href' '/struct.String.html'
+// @has - '//pre[@class="rust"]//a/@href' '/primitive.u32.html'
+// @has - '//pre[@class="rust"]//a/@href' '/primitive.str.html'
+// @count - '//pre[@class="rust"]//a[@href="#23"]' 5
+// @has - '//pre[@class="rust"]//a[@href="../../source_code/struct.SourceCode.html"]' 'source_code::SourceCode'
 pub fn foo(a: u32, b: &str, c: String, d: Foo, e: bar::Bar, f: source_code::SourceCode) {
     let x = 12;
     let y: Foo = Foo;
     let z: Bar = bar::Bar { field: Foo };
     babar();
-    // @has - '//a[@href="#26"]' 'hello'
+    // @has - '//pre[@class="rust"]//a[@href="#26"]' 'hello'
     y.hello();
 }
 
-// @has - '//a[@href="auxiliary/source-code-bar.rs.html#14"]' 'bar::sub::Trait'
-// @has - '//a[@href="auxiliary/source-code-bar.rs.html#14"]' 'Trait'
+// @has - '//pre[@class="rust"]//a[@href="auxiliary/source-code-bar.rs.html#14"]' 'bar::sub::Trait'
+// @has - '//pre[@class="rust"]//a[@href="auxiliary/source-code-bar.rs.html#14"]' 'Trait'
 pub fn foo2<T: bar::sub::Trait, V: Trait>(t: &T, v: &V, b: bool) {}
 
 pub trait AnotherTrait {}
 pub trait WhyNot {}
 
-// @has - '//a[@href="#49"]' 'AnotherTrait'
-// @has - '//a[@href="#50"]' 'WhyNot'
+// @has - '//pre[@class="rust"]//a[@href="#49"]' 'AnotherTrait'
+// @has - '//pre[@class="rust"]//a[@href="#50"]' 'WhyNot'
 pub fn foo3<T, V>(t: &T, v: &V)
 where
     T: AnotherTrait,
@@ -59,11 +59,11 @@ where
 
 pub trait AnotherTrait2 {}
 
-// @has - '//a[@href="#60"]' 'AnotherTrait2'
+// @has - '//pre[@class="rust"]//a[@href="#60"]' 'AnotherTrait2'
 pub fn foo4() {
     let x: Vec<AnotherTrait2> = Vec::new();
 }
 
-// @has - '//a[@href="../../foo/primitive.bool.html"]' 'bool'
+// @has - '//pre[@class="rust"]//a[@href="../../foo/primitive.bool.html"]' 'bool'
 #[doc(primitive = "bool")]
 mod whatever {}
diff --git a/src/test/rustdoc/doc-notable_trait-slice.bare_fn_matches.html b/src/test/rustdoc/doc-notable_trait-slice.bare_fn_matches.html
new file mode 100644
index 000000000000..f2ec8320a052
--- /dev/null
+++ b/src/test/rustdoc/doc-notable_trait-slice.bare_fn_matches.html
@@ -0,0 +1 @@
+<script type="text/json" id="notable-traits-data">{"&amp;'static [SomeStruct]":"&lt;h3&gt;Notable traits for &lt;code&gt;&amp;amp;[&lt;a class=\"struct\" href=\"struct.SomeStruct.html\" title=\"struct doc_notable_trait_slice::SomeStruct\"&gt;SomeStruct&lt;/a&gt;]&lt;/code&gt;&lt;/h3&gt;&lt;pre class=\"content\"&gt;&lt;code&gt;&lt;span class=\"where fmt-newline\"&gt;impl &lt;a class=\"trait\" href=\"trait.SomeTrait.html\" title=\"trait doc_notable_trait_slice::SomeTrait\"&gt;SomeTrait&lt;/a&gt; for &amp;amp;[&lt;a class=\"struct\" href=\"struct.SomeStruct.html\" title=\"struct doc_notable_trait_slice::SomeStruct\"&gt;SomeStruct&lt;/a&gt;]&lt;/span&gt;"}</script>
\ No newline at end of file
diff --git a/src/test/rustdoc/doc-notable_trait-slice.rs b/src/test/rustdoc/doc-notable_trait-slice.rs
index b0d414027216..2411da8cd454 100644
--- a/src/test/rustdoc/doc-notable_trait-slice.rs
+++ b/src/test/rustdoc/doc-notable_trait-slice.rs
@@ -8,13 +8,13 @@ pub struct OtherStruct;
 impl SomeTrait for &[SomeStruct] {}
 
 // @has doc_notable_trait_slice/fn.bare_fn_matches.html
-// @has - '//code[@class="content"]' 'impl SomeTrait for &[SomeStruct]'
+// @snapshot bare_fn_matches - '//script[@id="notable-traits-data"]'
 pub fn bare_fn_matches() -> &'static [SomeStruct] {
     &[]
 }
 
 // @has doc_notable_trait_slice/fn.bare_fn_no_matches.html
-// @!has - '//code[@class="content"]' 'impl SomeTrait for &[SomeStruct]'
+// @count - '//script[@id="notable-traits-data"]' 0
 pub fn bare_fn_no_matches() -> &'static [OtherStruct] {
     &[]
 }
diff --git a/src/test/rustdoc/doc-notable_trait.bare-fn.html b/src/test/rustdoc/doc-notable_trait.bare-fn.html
new file mode 100644
index 000000000000..b426a4d7a8b7
--- /dev/null
+++ b/src/test/rustdoc/doc-notable_trait.bare-fn.html
@@ -0,0 +1 @@
+<script type="text/json" id="notable-traits-data">{"SomeStruct":"&lt;h3&gt;Notable traits for &lt;code&gt;&lt;a class=\"struct\" href=\"struct.SomeStruct.html\" title=\"struct doc_notable_trait::SomeStruct\"&gt;SomeStruct&lt;/a&gt;&lt;/code&gt;&lt;/h3&gt;&lt;pre class=\"content\"&gt;&lt;code&gt;&lt;span class=\"where fmt-newline\"&gt;impl &lt;a class=\"trait\" href=\"trait.SomeTrait.html\" title=\"trait doc_notable_trait::SomeTrait\"&gt;SomeTrait&lt;/a&gt; for &lt;a class=\"struct\" href=\"struct.SomeStruct.html\" title=\"struct doc_notable_trait::SomeStruct\"&gt;SomeStruct&lt;/a&gt;&lt;/span&gt;"}</script>
\ No newline at end of file
diff --git a/src/test/rustdoc/doc-notable_trait.rs b/src/test/rustdoc/doc-notable_trait.rs
index 58a24b855d6e..279faf554014 100644
--- a/src/test/rustdoc/doc-notable_trait.rs
+++ b/src/test/rustdoc/doc-notable_trait.rs
@@ -9,7 +9,8 @@ impl<T: SomeTrait> SomeTrait for Wrapper<T> {}
 #[doc(notable_trait)]
 pub trait SomeTrait {
     // @has doc_notable_trait/trait.SomeTrait.html
-    // @has - '//code[@class="content"]' 'impl<T: SomeTrait> SomeTrait for Wrapper<T>'
+    // @has - '//a[@class="notable-traits"]/@data-ty' 'Wrapper<Self>'
+    // @snapshot wrap-me - '//script[@id="notable-traits-data"]'
     fn wrap_me(self) -> Wrapper<Self> where Self: Sized {
         Wrapper {
             inner: self,
@@ -22,15 +23,16 @@ impl SomeTrait for SomeStruct {}
 
 impl SomeStruct {
     // @has doc_notable_trait/struct.SomeStruct.html
-    // @has - '//code[@class="content"]' 'impl SomeTrait for SomeStruct'
-    // @has - '//code[@class="content"]' 'impl<T: SomeTrait> SomeTrait for Wrapper<T>'
+    // @has - '//a[@class="notable-traits"]/@data-ty' 'SomeStruct'
+    // @snapshot some-struct-new - '//script[@id="notable-traits-data"]'
     pub fn new() -> SomeStruct {
         SomeStruct
     }
 }
 
 // @has doc_notable_trait/fn.bare_fn.html
-// @has - '//code[@class="content"]' 'impl SomeTrait for SomeStruct'
+// @has - '//a[@class="notable-traits"]/@data-ty' 'SomeStruct'
+// @snapshot bare-fn - '//script[@id="notable-traits-data"]'
 pub fn bare_fn() -> SomeStruct {
     SomeStruct
 }
diff --git a/src/test/rustdoc/doc-notable_trait.some-struct-new.html b/src/test/rustdoc/doc-notable_trait.some-struct-new.html
new file mode 100644
index 000000000000..4f8063807e67
--- /dev/null
+++ b/src/test/rustdoc/doc-notable_trait.some-struct-new.html
@@ -0,0 +1 @@
+<script type="text/json" id="notable-traits-data">{"SomeStruct":"&lt;h3&gt;Notable traits for &lt;code&gt;&lt;a class=\"struct\" href=\"struct.SomeStruct.html\" title=\"struct doc_notable_trait::SomeStruct\"&gt;SomeStruct&lt;/a&gt;&lt;/code&gt;&lt;/h3&gt;&lt;pre class=\"content\"&gt;&lt;code&gt;&lt;span class=\"where fmt-newline\"&gt;impl &lt;a class=\"trait\" href=\"trait.SomeTrait.html\" title=\"trait doc_notable_trait::SomeTrait\"&gt;SomeTrait&lt;/a&gt; for &lt;a class=\"struct\" href=\"struct.SomeStruct.html\" title=\"struct doc_notable_trait::SomeStruct\"&gt;SomeStruct&lt;/a&gt;&lt;/span&gt;","Wrapper&lt;Self&gt;":"&lt;h3&gt;Notable traits for &lt;code&gt;&lt;a class=\"struct\" href=\"struct.Wrapper.html\" title=\"struct doc_notable_trait::Wrapper\"&gt;Wrapper&lt;/a&gt;&amp;lt;T&amp;gt;&lt;/code&gt;&lt;/h3&gt;&lt;pre class=\"content\"&gt;&lt;code&gt;&lt;span class=\"where fmt-newline\"&gt;impl&amp;lt;T:&amp;nbsp;&lt;a class=\"trait\" href=\"trait.SomeTrait.html\" title=\"trait doc_notable_trait::SomeTrait\"&gt;SomeTrait&lt;/a&gt;&amp;gt; &lt;a class=\"trait\" href=\"trait.SomeTrait.html\" title=\"trait doc_notable_trait::SomeTrait\"&gt;SomeTrait&lt;/a&gt; for &lt;a class=\"struct\" href=\"struct.Wrapper.html\" title=\"struct doc_notable_trait::Wrapper\"&gt;Wrapper&lt;/a&gt;&amp;lt;T&amp;gt;&lt;/span&gt;"}</script>
\ No newline at end of file
diff --git a/src/test/rustdoc/doc-notable_trait.wrap-me.html b/src/test/rustdoc/doc-notable_trait.wrap-me.html
new file mode 100644
index 000000000000..bed2a38b24a2
--- /dev/null
+++ b/src/test/rustdoc/doc-notable_trait.wrap-me.html
@@ -0,0 +1 @@
+<script type="text/json" id="notable-traits-data">{"Wrapper&lt;Self&gt;":"&lt;h3&gt;Notable traits for &lt;code&gt;&lt;a class=\"struct\" href=\"struct.Wrapper.html\" title=\"struct doc_notable_trait::Wrapper\"&gt;Wrapper&lt;/a&gt;&amp;lt;T&amp;gt;&lt;/code&gt;&lt;/h3&gt;&lt;pre class=\"content\"&gt;&lt;code&gt;&lt;span class=\"where fmt-newline\"&gt;impl&amp;lt;T:&amp;nbsp;&lt;a class=\"trait\" href=\"trait.SomeTrait.html\" title=\"trait doc_notable_trait::SomeTrait\"&gt;SomeTrait&lt;/a&gt;&amp;gt; &lt;a class=\"trait\" href=\"trait.SomeTrait.html\" title=\"trait doc_notable_trait::SomeTrait\"&gt;SomeTrait&lt;/a&gt; for &lt;a class=\"struct\" href=\"struct.Wrapper.html\" title=\"struct doc_notable_trait::Wrapper\"&gt;Wrapper&lt;/a&gt;&amp;lt;T&amp;gt;&lt;/span&gt;"}</script>
\ No newline at end of file
diff --git a/src/test/rustdoc/doc-notable_trait_box_is_not_an_iterator.rs b/src/test/rustdoc/doc-notable_trait_box_is_not_an_iterator.rs
new file mode 100644
index 000000000000..3fb00c7db841
--- /dev/null
+++ b/src/test/rustdoc/doc-notable_trait_box_is_not_an_iterator.rs
@@ -0,0 +1,38 @@
+#![feature(doc_notable_trait)]
+#![feature(lang_items)]
+#![feature(no_core)]
+#![no_core]
+#[lang = "owned_box"]
+pub struct Box<T>;
+
+impl<T> Box<T> {
+    pub fn new(x: T) -> Box<T> {
+        Box
+    }
+}
+
+#[doc(notable_trait)]
+pub trait FakeIterator {}
+
+impl<I: FakeIterator> FakeIterator for Box<I> {}
+
+#[lang = "pin"]
+pub struct Pin<T>;
+
+impl<T> Pin<T> {
+    pub fn new(x: T) -> Pin<T> {
+        Pin
+    }
+}
+
+impl<I: FakeIterator> FakeIterator for Pin<I> {}
+
+// @!has doc_notable_trait_box_is_not_an_iterator/fn.foo.html '//*' 'Notable'
+pub fn foo<T>(x: T) -> Box<T> {
+    Box::new(x)
+}
+
+// @!has doc_notable_trait_box_is_not_an_iterator/fn.bar.html '//*' 'Notable'
+pub fn bar<T>(x: T) -> Pin<T> {
+    Pin::new(x)
+}
diff --git a/src/test/rustdoc/inline_cross/assoc_item_trait_bounds.rs b/src/test/rustdoc/inline_cross/assoc_item_trait_bounds.rs
index 5f4712aab5b1..db2491b87b4d 100644
--- a/src/test/rustdoc/inline_cross/assoc_item_trait_bounds.rs
+++ b/src/test/rustdoc/inline_cross/assoc_item_trait_bounds.rs
@@ -33,8 +33,12 @@ extern crate assoc_item_trait_bounds as aux;
 // @snapshot out9 - '//*[@id="associatedtype.Out9"]/*[@class="code-header"]'
 //
 // @has - '//*[@id="tymethod.make"]' \
-// "fn make<F>(F, impl FnMut(&str) -> bool)\
+// "fn make<F>(_: F, _: impl FnMut(&str) -> bool)\
 // where \
 //     F: FnOnce(u32) -> String, \
 //     Self::Out2<()>: Protocol<u8, Q0 = Self::Item, Q1 = ()>"
 pub use aux::Main;
+
+// @has main/trait.Aid.html
+// @has - '//*[@id="associatedtype.Result"]' "type Result<'inter: 'src>"
+pub use aux::Aid;
diff --git a/src/test/rustdoc/inline_cross/auxiliary/assoc_item_trait_bounds.rs b/src/test/rustdoc/inline_cross/auxiliary/assoc_item_trait_bounds.rs
index d326e61daea2..6644c8e41478 100644
--- a/src/test/rustdoc/inline_cross/auxiliary/assoc_item_trait_bounds.rs
+++ b/src/test/rustdoc/inline_cross/auxiliary/assoc_item_trait_bounds.rs
@@ -42,5 +42,5 @@ pub trait Helper {
 }
 
 pub trait Aid<'src> {
-    type Result<'inter>;
+    type Result<'inter: 'src>;
 }
diff --git a/src/test/rustdoc/inline_cross/auxiliary/dyn_trait.rs b/src/test/rustdoc/inline_cross/auxiliary/dyn_trait.rs
new file mode 100644
index 000000000000..9ac2e3d96deb
--- /dev/null
+++ b/src/test/rustdoc/inline_cross/auxiliary/dyn_trait.rs
@@ -0,0 +1,17 @@
+pub type Ty0 = dyn for<'any> FnOnce(&'any str) -> bool;
+
+pub type Ty1<'obj> = dyn std::fmt::Display + 'obj;
+
+pub type Ty2 = dyn for<'a, 'r> Container<'r, Item<'a, 'static> = ()>;
+
+pub type Ty3<'s> = &'s dyn ToString;
+
+pub fn func0(_: &(dyn Fn() + '_)) {}
+
+pub fn func1<'func>(_: &(dyn Fn() + 'func)) {}
+
+pub trait Container<'r> {
+    type Item<'a, 'ctx>;
+}
+
+pub trait Shape<'a> {}
diff --git a/src/test/rustdoc/inline_cross/dyn_trait.rs b/src/test/rustdoc/inline_cross/dyn_trait.rs
new file mode 100644
index 000000000000..fa760540e436
--- /dev/null
+++ b/src/test/rustdoc/inline_cross/dyn_trait.rs
@@ -0,0 +1,31 @@
+#![crate_name = "user"]
+
+// aux-crate:dyn_trait=dyn_trait.rs
+// edition:2021
+
+// @has user/type.Ty0.html
+// @has - '//*[@class="item-decl"]//code' "dyn for<'any> FnOnce(&'any str) -> bool + 'static"
+// FIXME(fmease): Hide default lifetime bound `'static`
+pub use dyn_trait::Ty0;
+
+// @has user/type.Ty1.html
+// @has - '//*[@class="item-decl"]//code' "dyn Display + 'obj"
+pub use dyn_trait::Ty1;
+
+// @has user/type.Ty2.html
+// @has - '//*[@class="item-decl"]//code' "dyn for<'a, 'r> Container<'r, Item<'a, 'static> = ()>"
+pub use dyn_trait::Ty2;
+
+// @has user/type.Ty3.html
+// @has - '//*[@class="item-decl"]//code' "&'s (dyn ToString + 's)"
+// FIXME(fmease): Hide default lifetime bound, render "&'s dyn ToString"
+pub use dyn_trait::Ty3;
+
+// @has user/fn.func0.html
+// @has - '//pre[@class="rust fn"]' "func0(_: &dyn Fn())"
+// FIXME(fmease): Show placeholder-lifetime bound, render "func0(_: &(dyn Fn() + '_))"
+pub use dyn_trait::func0;
+
+// @has user/fn.func1.html
+// @has - '//pre[@class="rust fn"]' "func1<'func>(_: &(dyn Fn() + 'func))"
+pub use dyn_trait::func1;
diff --git a/src/test/rustdoc/inline_cross/impl_trait.rs b/src/test/rustdoc/inline_cross/impl_trait.rs
index 6c1cf8252a9d..9c4f64659203 100644
--- a/src/test/rustdoc/inline_cross/impl_trait.rs
+++ b/src/test/rustdoc/inline_cross/impl_trait.rs
@@ -29,7 +29,7 @@ pub use impl_trait_aux::func4;
 // @has impl_trait/fn.func5.html
 // @has - '//pre[@class="rust fn"]' "func5("
 // @has - '//pre[@class="rust fn"]' "_f: impl for<'any> Fn(&'any str, &'any str) -> bool + for<'r> Other<T<'r> = ()>,"
-// @has - '//pre[@class="rust fn"]' "_a: impl for<'alpha, 'beta> Auxiliary<'alpha, Item<'beta> = fn(&'beta ())>"
+// @has - '//pre[@class="rust fn"]' "_a: impl for<'alpha, 'beta> Auxiliary<'alpha, Item<'beta> = fn(_: &'beta ())>"
 // @!has - '//pre[@class="rust fn"]' 'where'
 pub use impl_trait_aux::func5;
 
diff --git a/src/test/rustdoc/intra-doc/auxiliary/issue-103463-aux.rs b/src/test/rustdoc/intra-doc/auxiliary/issue-103463-aux.rs
new file mode 100644
index 000000000000..2b8fdec1f128
--- /dev/null
+++ b/src/test/rustdoc/intra-doc/auxiliary/issue-103463-aux.rs
@@ -0,0 +1,4 @@
+pub trait Trait {
+    /// [`u8::clone`]
+    fn method();
+}
diff --git a/src/test/rustdoc/intra-doc/issue-103463.rs b/src/test/rustdoc/intra-doc/issue-103463.rs
new file mode 100644
index 000000000000..4adf8a9a8a4a
--- /dev/null
+++ b/src/test/rustdoc/intra-doc/issue-103463.rs
@@ -0,0 +1,8 @@
+// The `Trait` is not pulled into the crate resulting in doc links in its methods being resolved.
+
+// aux-build:issue-103463-aux.rs
+
+extern crate issue_103463_aux;
+use issue_103463_aux::Trait;
+
+fn main() {}
diff --git a/src/test/rustdoc/intra-doc/issue-104145.rs b/src/test/rustdoc/intra-doc/issue-104145.rs
new file mode 100644
index 000000000000..9ce36740d60d
--- /dev/null
+++ b/src/test/rustdoc/intra-doc/issue-104145.rs
@@ -0,0 +1,14 @@
+// Doc links in `Trait`'s methods are resolved because it has a local impl.
+
+// aux-build:issue-103463-aux.rs
+
+extern crate issue_103463_aux;
+use issue_103463_aux::Trait;
+
+pub struct LocalType;
+
+impl Trait for LocalType {
+    fn method() {}
+}
+
+fn main() {}
diff --git a/src/test/rustdoc/issue-102154.rs b/src/test/rustdoc/issue-102154.rs
new file mode 100644
index 000000000000..b36f270806ff
--- /dev/null
+++ b/src/test/rustdoc/issue-102154.rs
@@ -0,0 +1,13 @@
+trait A<Y, N> {
+    type B;
+}
+type MaybeBox<T> = <T as A<T, Box<T>>>::B;
+struct P {
+    t: MaybeBox<P>
+}
+impl<Y, N> A<Y, N> for P {
+    type B = N;
+}
+fn main() {
+    let t: MaybeBox<P>;
+}
diff --git a/src/test/rustdoc/issue-20727.rs b/src/test/rustdoc/issue-20727.rs
index f7acffcb4e56..c1a98cd57daf 100644
--- a/src/test/rustdoc/issue-20727.rs
+++ b/src/test/rustdoc/issue-20727.rs
@@ -19,6 +19,6 @@ pub mod reexport {
     // @has - '//*[@class="rust trait"]' 'trait Deref {'
     // @has - '//*[@class="rust trait"]' 'type Target: ?Sized;'
     // @has - '//*[@class="rust trait"]' \
-    //      "fn deref(&'a self) -> &'a Self::Target;"
+    //      "fn deref<'a>(&'a self) -> &'a Self::Target;"
     pub use issue_20727::Deref;
 }
diff --git a/src/test/rustdoc/issue-41783.codeblock.html b/src/test/rustdoc/issue-41783.codeblock.html
index 89987491d1b4..3bca4536cd5b 100644
--- a/src/test/rustdoc/issue-41783.codeblock.html
+++ b/src/test/rustdoc/issue-41783.codeblock.html
@@ -1,5 +1,5 @@
 <code># single
 ## double
 ### triple
-<span class="attribute">#[outer]
+<span class="attr">#[outer]
 #![inner]</span></code>
diff --git a/src/test/rustdoc/issue-41783.rs b/src/test/rustdoc/issue-41783.rs
index 87267a750c61..769f984a274a 100644
--- a/src/test/rustdoc/issue-41783.rs
+++ b/src/test/rustdoc/issue-41783.rs
@@ -1,10 +1,10 @@
 // @has issue_41783/struct.Foo.html
 // @!hasraw - 'space'
 // @!hasraw - 'comment'
-// @hasraw - '<span class="attribute">#[outer]'
-// @!hasraw - '<span class="attribute">#[outer]</span>'
+// @hasraw - '<span class="attr">#[outer]'
+// @!hasraw - '<span class="attr">#[outer]</span>'
 // @hasraw - '#![inner]</span>'
-// @!hasraw - '<span class="attribute">#![inner]</span>'
+// @!hasraw - '<span class="attr">#![inner]</span>'
 // @snapshot 'codeblock' - '//*[@class="rustdoc-toggle top-doc"]/*[@class="docblock"]//pre/code'
 
 /// ```no_run
diff --git a/src/test/rustdoc/local-reexport-doc.rs b/src/test/rustdoc/local-reexport-doc.rs
new file mode 100644
index 000000000000..1c8468008dd0
--- /dev/null
+++ b/src/test/rustdoc/local-reexport-doc.rs
@@ -0,0 +1,16 @@
+// This test ensures that the reexports of local items also get the doc from
+// the reexport.
+
+#![crate_name = "foo"]
+
+// @has 'foo/fn.g.html'
+// @has - '//*[@class="rustdoc-toggle top-doc"]/*[@class="docblock"]' \
+// 'outer module inner module'
+
+mod inner_mod {
+    /// inner module
+    pub fn g() {}
+}
+
+/// outer module
+pub use inner_mod::g;
diff --git a/src/test/rustdoc/masked.rs b/src/test/rustdoc/masked.rs
index 80d5b99c0b03..875c026fd058 100644
--- a/src/test/rustdoc/masked.rs
+++ b/src/test/rustdoc/masked.rs
@@ -10,6 +10,7 @@ extern crate masked;
 // @!hasraw 'search-index.js' 'masked_method'
 
 // @!hasraw 'foo/struct.String.html' 'MaskedTrait'
+// @!hasraw 'foo/struct.String.html' 'MaskedBlanketTrait'
 // @!hasraw 'foo/struct.String.html' 'masked_method'
 pub use std::string::String;
 
diff --git a/src/test/rustdoc/multiple-import-levels.rs b/src/test/rustdoc/multiple-import-levels.rs
new file mode 100644
index 000000000000..1daae49cde9d
--- /dev/null
+++ b/src/test/rustdoc/multiple-import-levels.rs
@@ -0,0 +1,34 @@
+// The goal of this test is to ensure that the attributes of all imports are taken into
+// account.
+
+#![crate_name = "foo"]
+
+mod a {
+    /// 1
+    pub struct Type;
+}
+
+mod b {
+    /// 2
+    pub use crate::a::Type;
+}
+
+mod c {
+    /// 3
+    pub use crate::b::Type;
+    /// 4
+    pub use crate::b::Type as Woof;
+}
+
+// @has 'foo/struct.Type.html'
+// @has - '//*[@class="rustdoc-toggle top-doc"]/*[@class="docblock"]' 'foo 2 1'
+/// foo
+pub use b::Type;
+// @has 'foo/struct.Whatever.html'
+// @has - '//*[@class="rustdoc-toggle top-doc"]/*[@class="docblock"]' 'whatever 3 2 1'
+/// whatever
+pub use c::Type as Whatever;
+// @has 'foo/struct.Woof.html'
+// @has - '//*[@class="rustdoc-toggle top-doc"]/*[@class="docblock"]' 'a dog 4 2 1'
+/// a dog
+pub use c::Woof;
diff --git a/src/test/rustdoc/no-unit-struct-field.rs b/src/test/rustdoc/no-unit-struct-field.rs
new file mode 100644
index 000000000000..d301954b6b59
--- /dev/null
+++ b/src/test/rustdoc/no-unit-struct-field.rs
@@ -0,0 +1,18 @@
+// This test ensures that the tuple struct fields are not generated in the
+// search index.
+
+// @!hasraw search-index.js '"0"'
+// @!hasraw search-index.js '"1"'
+// @hasraw search-index.js '"foo_a"'
+// @hasraw search-index.js '"bar_a"'
+
+pub struct Bar(pub u32, pub u8);
+pub struct Foo {
+    pub foo_a: u8,
+}
+pub enum Enum {
+    Foo(u8),
+    Bar {
+        bar_a: u8,
+    },
+}
diff --git a/src/test/rustdoc/reexport-doc.rs b/src/test/rustdoc/reexport-doc.rs
new file mode 100644
index 000000000000..df2c889b4d57
--- /dev/null
+++ b/src/test/rustdoc/reexport-doc.rs
@@ -0,0 +1,8 @@
+// aux-build:reexport-doc-aux.rs
+
+extern crate reexport_doc_aux as dep;
+
+// @has 'reexport_doc/struct.Foo.html'
+// @count - '//p' 'These are the docs for Foo.' 1
+/// These are the docs for Foo.
+pub use dep::Foo;
diff --git a/src/test/rustdoc/rustc-incoherent-impls.rs b/src/test/rustdoc/rustc-incoherent-impls.rs
new file mode 100644
index 000000000000..3fdefbecc546
--- /dev/null
+++ b/src/test/rustdoc/rustc-incoherent-impls.rs
@@ -0,0 +1,28 @@
+// aux-build:incoherent-impl-types.rs
+// build-aux-docs
+
+#![crate_name = "foo"]
+#![feature(rustc_attrs)]
+
+extern crate incoherent_impl_types;
+
+// The only way this actually shows up is if the type gets inlined.
+#[doc(inline)]
+pub use incoherent_impl_types::FooTrait;
+
+// @has foo/trait.FooTrait.html
+// @count - '//section[@id="method.do_something"]' 1
+impl dyn FooTrait {
+    #[rustc_allow_incoherent_impl]
+    pub fn do_something() {}
+}
+
+#[doc(inline)]
+pub use incoherent_impl_types::FooStruct;
+
+// @has foo/struct.FooStruct.html
+// @count - '//section[@id="method.do_something"]' 1
+impl FooStruct {
+    #[rustc_allow_incoherent_impl]
+    pub fn do_something() {}
+}
diff --git a/src/test/rustdoc/spotlight-from-dependency.odd.html b/src/test/rustdoc/spotlight-from-dependency.odd.html
new file mode 100644
index 000000000000..1d02c13ebfb3
--- /dev/null
+++ b/src/test/rustdoc/spotlight-from-dependency.odd.html
@@ -0,0 +1 @@
+<script type="text/json" id="notable-traits-data">{"Odd":"&lt;h3&gt;Notable traits for &lt;code&gt;&lt;a class=\"struct\" href=\"struct.Odd.html\" title=\"struct foo::Odd\"&gt;Odd&lt;/a&gt;&lt;/code&gt;&lt;/h3&gt;&lt;pre class=\"content\"&gt;&lt;code&gt;&lt;span class=\"where fmt-newline\"&gt;impl &lt;a class=\"trait\" href=\"{{channel}}/core/iter/traits/iterator/trait.Iterator.html\" title=\"trait core::iter::traits::iterator::Iterator\"&gt;Iterator&lt;/a&gt; for &lt;a class=\"struct\" href=\"struct.Odd.html\" title=\"struct foo::Odd\"&gt;Odd&lt;/a&gt;&lt;/span&gt;&lt;span class=\"where fmt-newline\"&gt;    type &lt;a href=\"{{channel}}/core/iter/traits/iterator/trait.Iterator.html#associatedtype.Item\" class=\"associatedtype\"&gt;Item&lt;/a&gt; = &lt;a class=\"primitive\" href=\"{{channel}}/std/primitive.usize.html\"&gt;usize&lt;/a&gt;;&lt;/span&gt;"}</script>
\ No newline at end of file
diff --git a/src/test/rustdoc/spotlight-from-dependency.rs b/src/test/rustdoc/spotlight-from-dependency.rs
index 5245789212d8..090ad187d9cc 100644
--- a/src/test/rustdoc/spotlight-from-dependency.rs
+++ b/src/test/rustdoc/spotlight-from-dependency.rs
@@ -3,7 +3,8 @@
 use std::iter::Iterator;
 
 // @has foo/struct.Odd.html
-// @has - '//*[@id="method.new"]//span[@class="notable-traits"]//code/span' 'impl Iterator for Odd'
+// @has - '//*[@id="method.new"]//a[@class="notable-traits"]/@data-ty' 'Odd'
+// @snapshot odd - '//script[@id="notable-traits-data"]'
 pub struct Odd {
     current: usize,
 }
diff --git a/src/test/rustdoc/static-root-path.rs b/src/test/rustdoc/static-root-path.rs
index 08c055c5b8db..86928b0fb0a8 100644
--- a/src/test/rustdoc/static-root-path.rs
+++ b/src/test/rustdoc/static-root-path.rs
@@ -1,18 +1,18 @@
 // compile-flags:-Z unstable-options --static-root-path /cache/
 
 // @has static_root_path/struct.SomeStruct.html
-// @matchesraw - '"/cache/main\.js"'
-// @!matchesraw - '"\.\./main\.js"'
+// @matchesraw - '"/cache/main-'
+// @!matchesraw - '"\.\./main'
 // @matchesraw - 'data-root-path="\.\./"'
 // @!matchesraw - '"/cache/search-index\.js"'
 pub struct SomeStruct;
 
 // @has src/static_root_path/static-root-path.rs.html
-// @matchesraw - '"/cache/source-script\.js"'
-// @!matchesraw - '"\.\./\.\./source-script\.js"'
+// @matchesraw - '"/cache/source-script-'
+// @!matchesraw - '"\.\./\.\./source-script'
 // @matchesraw - '"\.\./\.\./source-files.js"'
 // @!matchesraw - '"/cache/source-files\.js"'
 
 // @has settings.html
-// @matchesraw - '/cache/settings\.js'
-// @!matchesraw - '\./settings\.js'
+// @matchesraw - '/cache/settings-'
+// @!matchesraw - '\../settings'
diff --git a/src/test/ui-fulldeps/session-diagnostic/diagnostic-derive.rs b/src/test/ui-fulldeps/session-diagnostic/diagnostic-derive.rs
index 46164d573b0b..411eb3fba483 100644
--- a/src/test/ui-fulldeps/session-diagnostic/diagnostic-derive.rs
+++ b/src/test/ui-fulldeps/session-diagnostic/diagnostic-derive.rs
@@ -40,9 +40,9 @@ struct HelloWarn {}
 //~^ ERROR unsupported type attribute for diagnostic derive enum
 enum DiagnosticOnEnum {
     Foo,
-//~^ ERROR diagnostic slug not specified
+    //~^ ERROR diagnostic slug not specified
     Bar,
-//~^ ERROR diagnostic slug not specified
+    //~^ ERROR diagnostic slug not specified
 }
 
 #[derive(Diagnostic)]
@@ -211,9 +211,10 @@ struct LabelOnNonSpan {
 #[diag(compiletest_example, code = "E0123")]
 struct Suggest {
     #[suggestion(suggestion, code = "This is the suggested code")]
-    #[suggestion_short(suggestion, code = "This is the suggested code")]
-    #[suggestion_hidden(suggestion, code = "This is the suggested code")]
-    #[suggestion_verbose(suggestion, code = "This is the suggested code")]
+    #[suggestion(suggestion, code = "This is the suggested code", style = "normal")]
+    #[suggestion(suggestion, code = "This is the suggested code", style = "short")]
+    #[suggestion(suggestion, code = "This is the suggested code", style = "hidden")]
+    #[suggestion(suggestion, code = "This is the suggested code", style = "verbose")]
     suggestion: (Span, Applicability),
 }
 
@@ -536,8 +537,7 @@ struct LabelWithTrailingList {
 
 #[derive(LintDiagnostic)]
 #[diag(compiletest_example)]
-struct LintsGood {
-}
+struct LintsGood {}
 
 #[derive(LintDiagnostic)]
 #[diag(compiletest_example)]
@@ -683,7 +683,7 @@ struct RawIdentDiagnosticArg {
 #[diag(compiletest_example)]
 struct SubdiagnosticBad {
     #[subdiagnostic(bad)]
-//~^ ERROR `#[subdiagnostic(bad)]` is not a valid attribute
+    //~^ ERROR `#[subdiagnostic(bad)]` is not a valid attribute
     note: Note,
 }
 
@@ -691,7 +691,7 @@ struct SubdiagnosticBad {
 #[diag(compiletest_example)]
 struct SubdiagnosticBadStr {
     #[subdiagnostic = "bad"]
-//~^ ERROR `#[subdiagnostic = ...]` is not a valid attribute
+    //~^ ERROR `#[subdiagnostic = ...]` is not a valid attribute
     note: Note,
 }
 
@@ -699,7 +699,7 @@ struct SubdiagnosticBadStr {
 #[diag(compiletest_example)]
 struct SubdiagnosticBadTwice {
     #[subdiagnostic(bad, bad)]
-//~^ ERROR `#[subdiagnostic(...)]` is not a valid attribute
+    //~^ ERROR `#[subdiagnostic(...)]` is not a valid attribute
     note: Note,
 }
 
@@ -707,7 +707,7 @@ struct SubdiagnosticBadTwice {
 #[diag(compiletest_example)]
 struct SubdiagnosticBadLitStr {
     #[subdiagnostic("bad")]
-//~^ ERROR `#[subdiagnostic("...")]` is not a valid attribute
+    //~^ ERROR `#[subdiagnostic("...")]` is not a valid attribute
     note: Note,
 }
 
@@ -715,7 +715,7 @@ struct SubdiagnosticBadLitStr {
 #[diag(compiletest_example)]
 struct SubdiagnosticEagerLint {
     #[subdiagnostic(eager)]
-//~^ ERROR `#[subdiagnostic(...)]` is not a valid attribute
+    //~^ ERROR `#[subdiagnostic(...)]` is not a valid attribute
     note: Note,
 }
 
@@ -731,11 +731,7 @@ struct SubdiagnosticEagerCorrect {
 // after the `span_suggestion` call - which breaks eager translation.
 
 #[derive(Subdiagnostic)]
-#[suggestion_short(
-    use_instead,
-    applicability = "machine-applicable",
-    code = "{correct}"
-)]
+#[suggestion(use_instead, applicability = "machine-applicable", code = "{correct}")]
 pub(crate) struct SubdiagnosticWithSuggestion {
     #[primary_span]
     span: Span,
@@ -758,3 +754,48 @@ struct WithDocComment {
     #[primary_span]
     span: Span,
 }
+
+#[derive(Diagnostic)]
+#[diag(compiletest_example)]
+struct SuggestionsGood {
+    #[suggestion(code("foo", "bar"))]
+    sub: Span,
+}
+
+#[derive(Diagnostic)]
+#[diag(compiletest_example)]
+struct SuggestionsSingleItem {
+    #[suggestion(code("foo"))]
+    sub: Span,
+}
+
+#[derive(Diagnostic)]
+#[diag(compiletest_example)]
+struct SuggestionsNoItem {
+    #[suggestion(code())]
+    //~^ ERROR expected at least one string literal for `code(...)`
+    sub: Span,
+}
+
+#[derive(Diagnostic)]
+#[diag(compiletest_example)]
+struct SuggestionsInvalidItem {
+    #[suggestion(code(foo))]
+    //~^ ERROR `code(...)` must contain only string literals
+    sub: Span,
+}
+
+#[derive(Diagnostic)]
+#[diag(compiletest_example)]
+struct SuggestionsInvalidLiteral {
+    #[suggestion(code = 3)]
+    //~^ ERROR `code = "..."`/`code(...)` must contain only string literals
+    sub: Span,
+}
+
+#[derive(Diagnostic)]
+#[diag(compiletest_example)]
+struct SuggestionStyleGood {
+    #[suggestion(code = "", style = "hidden")]
+    sub: Span,
+}
diff --git a/src/test/ui-fulldeps/session-diagnostic/diagnostic-derive.stderr b/src/test/ui-fulldeps/session-diagnostic/diagnostic-derive.stderr
index 0a1c4bddb06a..b4c211db47cd 100644
--- a/src/test/ui-fulldeps/session-diagnostic/diagnostic-derive.stderr
+++ b/src/test/ui-fulldeps/session-diagnostic/diagnostic-derive.stderr
@@ -261,41 +261,41 @@ LL |     #[label(label)]
    |     ^^^^^^^^^^^^^^^
 
 error: suggestion without `code = "..."`
-  --> $DIR/diagnostic-derive.rs:223:5
+  --> $DIR/diagnostic-derive.rs:224:5
    |
 LL |     #[suggestion(suggestion)]
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: `#[suggestion(nonsense = ...)]` is not a valid attribute
-  --> $DIR/diagnostic-derive.rs:231:18
+  --> $DIR/diagnostic-derive.rs:232:18
    |
 LL |     #[suggestion(nonsense = "bar")]
    |                  ^^^^^^^^^^^^^^^^
    |
-   = help: only `code` and `applicability` are valid nested attributes
+   = help: only `style`, `code` and `applicability` are valid nested attributes
 
 error: suggestion without `code = "..."`
-  --> $DIR/diagnostic-derive.rs:231:5
+  --> $DIR/diagnostic-derive.rs:232:5
    |
 LL |     #[suggestion(nonsense = "bar")]
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: `#[suggestion(msg = ...)]` is not a valid attribute
-  --> $DIR/diagnostic-derive.rs:240:18
+  --> $DIR/diagnostic-derive.rs:241:18
    |
 LL |     #[suggestion(msg = "bar")]
    |                  ^^^^^^^^^^^
    |
-   = help: only `code` and `applicability` are valid nested attributes
+   = help: only `style`, `code` and `applicability` are valid nested attributes
 
 error: suggestion without `code = "..."`
-  --> $DIR/diagnostic-derive.rs:240:5
+  --> $DIR/diagnostic-derive.rs:241:5
    |
 LL |     #[suggestion(msg = "bar")]
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: wrong field type for suggestion
-  --> $DIR/diagnostic-derive.rs:263:5
+  --> $DIR/diagnostic-derive.rs:264:5
    |
 LL | /     #[suggestion(suggestion, code = "This is suggested code")]
 LL | |
@@ -305,55 +305,55 @@ LL | |     suggestion: Applicability,
    = help: `#[suggestion(...)]` should be applied to fields of type `Span` or `(Span, Applicability)`
 
 error: specified multiple times
-  --> $DIR/diagnostic-derive.rs:279:24
+  --> $DIR/diagnostic-derive.rs:280:24
    |
 LL |     suggestion: (Span, Span, Applicability),
    |                        ^^^^
    |
 note: previously specified here
-  --> $DIR/diagnostic-derive.rs:279:18
+  --> $DIR/diagnostic-derive.rs:280:18
    |
 LL |     suggestion: (Span, Span, Applicability),
    |                  ^^^^
 
 error: specified multiple times
-  --> $DIR/diagnostic-derive.rs:287:33
+  --> $DIR/diagnostic-derive.rs:288:33
    |
 LL |     suggestion: (Applicability, Applicability, Span),
    |                                 ^^^^^^^^^^^^^
    |
 note: previously specified here
-  --> $DIR/diagnostic-derive.rs:287:18
+  --> $DIR/diagnostic-derive.rs:288:18
    |
 LL |     suggestion: (Applicability, Applicability, Span),
    |                  ^^^^^^^^^^^^^
 
 error: `#[label = ...]` is not a valid attribute
-  --> $DIR/diagnostic-derive.rs:294:5
+  --> $DIR/diagnostic-derive.rs:295:5
    |
 LL |     #[label = "bar"]
    |     ^^^^^^^^^^^^^^^^
 
 error: specified multiple times
-  --> $DIR/diagnostic-derive.rs:445:44
+  --> $DIR/diagnostic-derive.rs:446:44
    |
 LL |     #[suggestion(suggestion, code = "...", applicability = "maybe-incorrect")]
    |                                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
 note: previously specified here
-  --> $DIR/diagnostic-derive.rs:447:24
+  --> $DIR/diagnostic-derive.rs:448:24
    |
 LL |     suggestion: (Span, Applicability),
    |                        ^^^^^^^^^^^^^
 
 error: invalid applicability
-  --> $DIR/diagnostic-derive.rs:453:44
+  --> $DIR/diagnostic-derive.rs:454:44
    |
 LL |     #[suggestion(suggestion, code = "...", applicability = "batman")]
    |                                            ^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: `#[label(foo)]` is not a valid attribute
-  --> $DIR/diagnostic-derive.rs:516:20
+  --> $DIR/diagnostic-derive.rs:517:20
    |
 LL |     #[label(label, foo)]
    |                    ^^^
@@ -361,13 +361,13 @@ LL |     #[label(label, foo)]
    = help: a diagnostic slug must be the first argument to the attribute
 
 error: `#[label(foo = ...)]` is not a valid attribute
-  --> $DIR/diagnostic-derive.rs:524:20
+  --> $DIR/diagnostic-derive.rs:525:20
    |
 LL |     #[label(label, foo = "...")]
    |                    ^^^^^^^^^^^
 
 error: `#[label(foo(...))]` is not a valid attribute
-  --> $DIR/diagnostic-derive.rs:532:20
+  --> $DIR/diagnostic-derive.rs:533:20
    |
 LL |     #[label(label, foo("..."))]
    |                    ^^^^^^^^^^
@@ -573,6 +573,24 @@ LL |     #[subdiagnostic(eager)]
    |
    = help: eager subdiagnostics are not supported on lints
 
+error: expected at least one string literal for `code(...)`
+  --> $DIR/diagnostic-derive.rs:775:18
+   |
+LL |     #[suggestion(code())]
+   |                  ^^^^^^
+
+error: `code(...)` must contain only string literals
+  --> $DIR/diagnostic-derive.rs:783:23
+   |
+LL |     #[suggestion(code(foo))]
+   |                       ^^^
+
+error: `code = "..."`/`code(...)` must contain only string literals
+  --> $DIR/diagnostic-derive.rs:791:18
+   |
+LL |     #[suggestion(code = 3)]
+   |                  ^^^^^^^^
+
 error: cannot find attribute `nonsense` in this scope
   --> $DIR/diagnostic-derive.rs:55:3
    |
@@ -634,7 +652,7 @@ LL | #[diag(nonsense, code = "E0123")]
    |        ^^^^^^^^ not found in `rustc_errors::fluent`
 
 error[E0277]: the trait bound `Hello: IntoDiagnosticArg` is not satisfied
-  --> $DIR/diagnostic-derive.rs:338:10
+  --> $DIR/diagnostic-derive.rs:339:10
    |
 LL | #[derive(Diagnostic)]
    |          ^^^^^^^^^^ the trait `IntoDiagnosticArg` is not implemented for `Hello`
@@ -647,7 +665,7 @@ LL |         arg: impl IntoDiagnosticArg,
    |                   ^^^^^^^^^^^^^^^^^ required by this bound in `DiagnosticBuilder::<'a, G>::set_arg`
    = note: this error originates in the derive macro `Diagnostic` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: aborting due to 80 previous errors
+error: aborting due to 83 previous errors
 
 Some errors have detailed explanations: E0277, E0425.
 For more information about an error, try `rustc --explain E0277`.
diff --git a/src/test/ui-fulldeps/session-diagnostic/subdiagnostic-derive.rs b/src/test/ui-fulldeps/session-diagnostic/subdiagnostic-derive.rs
index 9088ca6ce462..078ec3baac9f 100644
--- a/src/test/ui-fulldeps/session-diagnostic/subdiagnostic-derive.rs
+++ b/src/test/ui-fulldeps/session-diagnostic/subdiagnostic-derive.rs
@@ -11,13 +11,13 @@
 #![crate_type = "lib"]
 
 extern crate rustc_errors;
+extern crate rustc_macros;
 extern crate rustc_session;
 extern crate rustc_span;
-extern crate rustc_macros;
 
 use rustc_errors::Applicability;
-use rustc_span::Span;
 use rustc_macros::Subdiagnostic;
+use rustc_span::Span;
 
 #[derive(Subdiagnostic)]
 #[label(parser_add_paren)]
@@ -40,7 +40,7 @@ enum B {
         #[primary_span]
         span: Span,
         var: String,
-    }
+    },
 }
 
 #[derive(Subdiagnostic)]
@@ -165,7 +165,7 @@ enum P {
         #[primary_span]
         span: Span,
         var: String,
-    }
+    },
 }
 
 #[derive(Subdiagnostic)]
@@ -177,7 +177,7 @@ enum Q {
         #[primary_span]
         span: Span,
         var: String,
-    }
+    },
 }
 
 #[derive(Subdiagnostic)]
@@ -189,7 +189,7 @@ enum R {
         #[primary_span]
         span: Span,
         var: String,
-    }
+    },
 }
 
 #[derive(Subdiagnostic)]
@@ -201,7 +201,7 @@ enum S {
         #[primary_span]
         span: Span,
         var: String,
-    }
+    },
 }
 
 #[derive(Subdiagnostic)]
@@ -213,7 +213,7 @@ enum T {
         #[primary_span]
         span: Span,
         var: String,
-    }
+    },
 }
 
 #[derive(Subdiagnostic)]
@@ -225,7 +225,7 @@ enum U {
         #[primary_span]
         span: Span,
         var: String,
-    }
+    },
 }
 
 #[derive(Subdiagnostic)]
@@ -240,7 +240,7 @@ enum V {
         #[primary_span]
         span: Span,
         var: String,
-    }
+    },
 }
 
 #[derive(Subdiagnostic)]
@@ -301,14 +301,14 @@ struct AB {
     #[primary_span]
     span: Span,
     #[skip_arg]
-    z: Z
+    z: Z,
 }
 
 #[derive(Subdiagnostic)]
 union AC {
-//~^ ERROR unexpected unsupported untagged union
+    //~^ ERROR unexpected unsupported untagged union
     span: u32,
-    b: u64
+    b: u64,
 }
 
 #[derive(Subdiagnostic)]
@@ -372,7 +372,7 @@ enum AI {
         #[applicability]
         applicability: Applicability,
         var: String,
-    }
+    },
 }
 
 #[derive(Subdiagnostic)]
@@ -427,7 +427,7 @@ struct AN {
 }
 
 #[derive(Subdiagnostic)]
-#[suggestion(parser_add_paren, code ="...", applicability = "foo")]
+#[suggestion(parser_add_paren, code = "...", applicability = "foo")]
 //~^ ERROR invalid applicability
 struct AO {
     #[primary_span]
@@ -437,7 +437,7 @@ struct AO {
 #[derive(Subdiagnostic)]
 #[help(parser_add_paren)]
 struct AP {
-    var: String
+    var: String,
 }
 
 #[derive(Subdiagnostic)]
@@ -452,7 +452,7 @@ struct AR {
 }
 
 #[derive(Subdiagnostic)]
-#[suggestion(parser_add_paren, code ="...", applicability = "machine-applicable")]
+#[suggestion(parser_add_paren, code = "...", applicability = "machine-applicable")]
 struct AS {
     #[primary_span]
     span: Span,
@@ -467,11 +467,11 @@ enum AT {
         #[primary_span]
         span: Span,
         var: String,
-    }
+    },
 }
 
 #[derive(Subdiagnostic)]
-#[suggestion(parser_add_paren, code ="{var}", applicability = "machine-applicable")]
+#[suggestion(parser_add_paren, code = "{var}", applicability = "machine-applicable")]
 struct AU {
     #[primary_span]
     span: Span,
@@ -479,7 +479,7 @@ struct AU {
 }
 
 #[derive(Subdiagnostic)]
-#[suggestion(parser_add_paren, code ="{var}", applicability = "machine-applicable")]
+#[suggestion(parser_add_paren, code = "{var}", applicability = "machine-applicable")]
 //~^ ERROR `var` doesn't refer to a field on this type
 struct AV {
     #[primary_span]
@@ -488,22 +488,22 @@ struct AV {
 
 #[derive(Subdiagnostic)]
 enum AW {
-    #[suggestion(parser_add_paren, code ="{var}", applicability = "machine-applicable")]
+    #[suggestion(parser_add_paren, code = "{var}", applicability = "machine-applicable")]
     A {
         #[primary_span]
         span: Span,
         var: String,
-    }
+    },
 }
 
 #[derive(Subdiagnostic)]
 enum AX {
-    #[suggestion(parser_add_paren, code ="{var}", applicability = "machine-applicable")]
-//~^ ERROR `var` doesn't refer to a field on this type
+    #[suggestion(parser_add_paren, code = "{var}", applicability = "machine-applicable")]
+    //~^ ERROR `var` doesn't refer to a field on this type
     A {
         #[primary_span]
         span: Span,
-    }
+    },
 }
 
 #[derive(Subdiagnostic)]
@@ -659,5 +659,142 @@ enum BL {
         /// ..and the field
         #[primary_span]
         span: Span,
-    }
+    },
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion(parser_add_paren)]
+struct BM {
+    #[suggestion_part(code("foo"))]
+    //~^ ERROR expected exactly one string literal for `code = ...`
+    span: Span,
+    r#type: String,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion(parser_add_paren)]
+struct BN {
+    #[suggestion_part(code("foo", "bar"))]
+    //~^ ERROR expected exactly one string literal for `code = ...`
+    span: Span,
+    r#type: String,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion(parser_add_paren)]
+struct BO {
+    #[suggestion_part(code(3))]
+    //~^ ERROR expected exactly one string literal for `code = ...`
+    span: Span,
+    r#type: String,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion(parser_add_paren)]
+struct BP {
+    #[suggestion_part(code())]
+    //~^ ERROR expected exactly one string literal for `code = ...`
+    span: Span,
+    r#type: String,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion(parser_add_paren)]
+struct BQ {
+    #[suggestion_part(code = 3)]
+    //~^ ERROR `code = "..."`/`code(...)` must contain only string literals
+    span: Span,
+    r#type: String,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion(parser_add_paren, code = "")]
+struct SuggestionStyleDefault {
+    #[primary_span]
+    sub: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion(parser_add_paren, code = "", style = "short")]
+struct SuggestionStyleShort {
+    #[primary_span]
+    sub: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion(parser_add_paren, code = "", style = "hidden")]
+struct SuggestionStyleHidden {
+    #[primary_span]
+    sub: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion(parser_add_paren, code = "", style = "verbose")]
+struct SuggestionStyleVerbose {
+    #[primary_span]
+    sub: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion(parser_add_paren, code = "", style = "tool-only")]
+struct SuggestionStyleToolOnly {
+    #[primary_span]
+    sub: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion(parser_add_paren, code = "", style = "hidden", style = "normal")]
+//~^ ERROR specified multiple times
+//~| NOTE previously specified here
+struct SuggestionStyleTwice {
+    #[primary_span]
+    sub: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion_hidden(parser_add_paren, code = "")]
+//~^ ERROR #[suggestion_hidden(...)]` is not a valid attribute
+struct SuggestionStyleOldSyntax {
+    #[primary_span]
+    sub: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion_hidden(parser_add_paren, code = "", style = "normal")]
+//~^ ERROR #[suggestion_hidden(...)]` is not a valid attribute
+struct SuggestionStyleOldAndNewSyntax {
+    #[primary_span]
+    sub: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion(parser_add_paren, code = "", style = "foo")]
+//~^ ERROR invalid suggestion style
+struct SuggestionStyleInvalid1 {
+    #[primary_span]
+    sub: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion(parser_add_paren, code = "", style = 42)]
+//~^ ERROR `#[suggestion(style = ...)]` is not a valid attribute
+struct SuggestionStyleInvalid2 {
+    #[primary_span]
+    sub: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion(parser_add_paren, code = "", style)]
+//~^ ERROR `#[suggestion(style)]` is not a valid attribute
+struct SuggestionStyleInvalid3 {
+    #[primary_span]
+    sub: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion(parser_add_paren, code = "", style("foo"))]
+//~^ ERROR `#[suggestion(style(...))]` is not a valid attribute
+struct SuggestionStyleInvalid4 {
+    #[primary_span]
+    sub: Span,
 }
diff --git a/src/test/ui-fulldeps/session-diagnostic/subdiagnostic-derive.stderr b/src/test/ui-fulldeps/session-diagnostic/subdiagnostic-derive.stderr
index b21f9cc94a98..8e06c43e6d0a 100644
--- a/src/test/ui-fulldeps/session-diagnostic/subdiagnostic-derive.stderr
+++ b/src/test/ui-fulldeps/session-diagnostic/subdiagnostic-derive.stderr
@@ -186,7 +186,7 @@ error: unexpected unsupported untagged union
 LL | / union AC {
 LL | |
 LL | |     span: u32,
-LL | |     b: u64
+LL | |     b: u64,
 LL | | }
    | |_^
 
@@ -253,10 +253,10 @@ LL | #[suggestion(parser_add_paren)]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: invalid applicability
-  --> $DIR/subdiagnostic-derive.rs:430:45
+  --> $DIR/subdiagnostic-derive.rs:430:46
    |
-LL | #[suggestion(parser_add_paren, code ="...", applicability = "foo")]
-   |                                             ^^^^^^^^^^^^^^^^^^^^^
+LL | #[suggestion(parser_add_paren, code = "...", applicability = "foo")]
+   |                                              ^^^^^^^^^^^^^^^^^^^^^
 
 error: suggestion without `#[primary_span]` field
   --> $DIR/subdiagnostic-derive.rs:448:1
@@ -275,16 +275,16 @@ LL | #[label]
    | ^^^^^^^^
 
 error: `var` doesn't refer to a field on this type
-  --> $DIR/subdiagnostic-derive.rs:482:38
+  --> $DIR/subdiagnostic-derive.rs:482:39
    |
-LL | #[suggestion(parser_add_paren, code ="{var}", applicability = "machine-applicable")]
-   |                                      ^^^^^^^
+LL | #[suggestion(parser_add_paren, code = "{var}", applicability = "machine-applicable")]
+   |                                       ^^^^^^^
 
 error: `var` doesn't refer to a field on this type
-  --> $DIR/subdiagnostic-derive.rs:501:42
+  --> $DIR/subdiagnostic-derive.rs:501:43
    |
-LL |     #[suggestion(parser_add_paren, code ="{var}", applicability = "machine-applicable")]
-   |                                          ^^^^^^^
+LL |     #[suggestion(parser_add_paren, code = "{var}", applicability = "machine-applicable")]
+   |                                           ^^^^^^^
 
 error: `#[suggestion_part]` is not a valid attribute
   --> $DIR/subdiagnostic-derive.rs:524:5
@@ -320,7 +320,7 @@ error: `#[multipart_suggestion(code = ...)]` is not a valid attribute
 LL | #[multipart_suggestion(parser_add_paren, code = "...", applicability = "machine-applicable")]
    |                                          ^^^^^^^^^^^^
    |
-   = help: only `applicability` is a valid nested attributes
+   = help: only `style` and `applicability` are valid nested attributes
 
 error: multipart suggestion without any `#[suggestion_part(...)]` fields
   --> $DIR/subdiagnostic-derive.rs:536:1
@@ -415,6 +415,92 @@ error: `#[applicability]` has no effect if all `#[suggestion]`/`#[multipart_sugg
 LL |     #[applicability]
    |     ^^^^^^^^^^^^^^^^
 
+error: expected exactly one string literal for `code = ...`
+  --> $DIR/subdiagnostic-derive.rs:668:23
+   |
+LL |     #[suggestion_part(code("foo"))]
+   |                       ^^^^^^^^^^^
+
+error: expected exactly one string literal for `code = ...`
+  --> $DIR/subdiagnostic-derive.rs:677:23
+   |
+LL |     #[suggestion_part(code("foo", "bar"))]
+   |                       ^^^^^^^^^^^^^^^^^^
+
+error: expected exactly one string literal for `code = ...`
+  --> $DIR/subdiagnostic-derive.rs:686:23
+   |
+LL |     #[suggestion_part(code(3))]
+   |                       ^^^^^^^
+
+error: expected exactly one string literal for `code = ...`
+  --> $DIR/subdiagnostic-derive.rs:695:23
+   |
+LL |     #[suggestion_part(code())]
+   |                       ^^^^^^
+
+error: `code = "..."`/`code(...)` must contain only string literals
+  --> $DIR/subdiagnostic-derive.rs:704:23
+   |
+LL |     #[suggestion_part(code = 3)]
+   |                       ^^^^^^^^
+
+error: specified multiple times
+  --> $DIR/subdiagnostic-derive.rs:746:61
+   |
+LL | #[suggestion(parser_add_paren, code = "", style = "hidden", style = "normal")]
+   |                                                             ^^^^^^^^^^^^^^^^
+   |
+note: previously specified here
+  --> $DIR/subdiagnostic-derive.rs:746:43
+   |
+LL | #[suggestion(parser_add_paren, code = "", style = "hidden", style = "normal")]
+   |                                           ^^^^^^^^^^^^^^^^
+
+error: `#[suggestion_hidden(...)]` is not a valid attribute
+  --> $DIR/subdiagnostic-derive.rs:755:1
+   |
+LL | #[suggestion_hidden(parser_add_paren, code = "")]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = help: Use `#[suggestion(..., style = "hidden")]` instead
+
+error: `#[suggestion_hidden(...)]` is not a valid attribute
+  --> $DIR/subdiagnostic-derive.rs:763:1
+   |
+LL | #[suggestion_hidden(parser_add_paren, code = "", style = "normal")]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = help: Use `#[suggestion(..., style = "hidden")]` instead
+
+error: invalid suggestion style
+  --> $DIR/subdiagnostic-derive.rs:771:51
+   |
+LL | #[suggestion(parser_add_paren, code = "", style = "foo")]
+   |                                                   ^^^^^
+   |
+   = help: valid styles are `normal`, `short`, `hidden`, `verbose` and `tool-only`
+
+error: `#[suggestion(style = ...)]` is not a valid attribute
+  --> $DIR/subdiagnostic-derive.rs:779:43
+   |
+LL | #[suggestion(parser_add_paren, code = "", style = 42)]
+   |                                           ^^^^^^^^^^
+
+error: `#[suggestion(style)]` is not a valid attribute
+  --> $DIR/subdiagnostic-derive.rs:787:43
+   |
+LL | #[suggestion(parser_add_paren, code = "", style)]
+   |                                           ^^^^^
+   |
+   = help: a diagnostic slug must be the first argument to the attribute
+
+error: `#[suggestion(style(...))]` is not a valid attribute
+  --> $DIR/subdiagnostic-derive.rs:795:43
+   |
+LL | #[suggestion(parser_add_paren, code = "", style("foo"))]
+   |                                           ^^^^^^^^^^^^
+
 error: cannot find attribute `foo` in this scope
   --> $DIR/subdiagnostic-derive.rs:63:3
    |
@@ -475,6 +561,6 @@ error[E0425]: cannot find value `slug` in module `rustc_errors::fluent`
 LL | #[label(slug)]
    |         ^^^^ not found in `rustc_errors::fluent`
 
-error: aborting due to 67 previous errors
+error: aborting due to 79 previous errors
 
 For more information about this error, try `rustc --explain E0425`.
diff --git a/src/test/ui/abi/homogenous-floats-target-feature-mixup.rs b/src/test/ui/abi/homogenous-floats-target-feature-mixup.rs
new file mode 100644
index 000000000000..d7f5e19219ed
--- /dev/null
+++ b/src/test/ui/abi/homogenous-floats-target-feature-mixup.rs
@@ -0,0 +1,192 @@
+// This test check that even if we mixup target feature of function with homogenous floats,
+// the abi is sound and still produce the right answer.
+//
+// This is basically the same test as src/test/ui/simd/target-feature-mixup.rs but for floats and
+// without #[repr(simd)]
+
+// run-pass
+// ignore-emscripten
+// ignore-sgx no processes
+
+#![feature(avx512_target_feature)]
+
+#![allow(overflowing_literals)]
+#![allow(unused_variables)]
+
+use std::process::{Command, ExitStatus};
+use std::env;
+
+fn main() {
+    if let Some(level) = env::args().nth(1) {
+        return test::main(&level)
+    }
+
+    match std::env::var("TARGET") {
+        Ok(s) => {
+            // Skip this tests on i586-unknown-linux-gnu where sse2 is disabled
+            if s.contains("i586") {
+                return
+            }
+        }
+        Err(_) => return,
+    }
+
+    let me = env::current_exe().unwrap();
+    for level in ["sse", "avx", "avx512"].iter() {
+        let status = Command::new(&me).arg(level).status().unwrap();
+        if status.success() {
+            println!("success with {}", level);
+            continue
+        }
+
+        // We don't actually know if our computer has the requisite target features
+        // for the test below. Testing for that will get added to libstd later so
+        // for now just assume sigill means this is a machine that can't run this test.
+        if is_sigill(status) {
+            println!("sigill with {}, assuming spurious", level);
+            continue
+        }
+        panic!("invalid status at {}: {}", level, status);
+    }
+}
+
+#[cfg(unix)]
+fn is_sigill(status: ExitStatus) -> bool {
+    use std::os::unix::prelude::*;
+    status.signal() == Some(4)
+}
+
+#[cfg(windows)]
+fn is_sigill(status: ExitStatus) -> bool {
+    status.code() == Some(0xc000001d)
+}
+
+#[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
+#[allow(nonstandard_style)]
+mod test {
+    #[derive(PartialEq, Debug, Clone, Copy)]
+    struct f32x2(f32, f32);
+
+    #[derive(PartialEq, Debug, Clone, Copy)]
+    struct f32x4(f32, f32, f32, f32);
+
+    #[derive(PartialEq, Debug, Clone, Copy)]
+    struct f32x8(f32, f32, f32, f32, f32, f32, f32, f32);
+
+    pub fn main(level: &str) {
+        unsafe {
+            main_normal(level);
+            main_sse(level);
+            if level == "sse" {
+                return
+            }
+            main_avx(level);
+            if level == "avx" {
+                return
+            }
+            main_avx512(level);
+        }
+    }
+
+    macro_rules! mains {
+        ($(
+            $(#[$attr:meta])*
+            unsafe fn $main:ident(level: &str) {
+                ...
+            }
+        )*) => ($(
+            $(#[$attr])*
+            unsafe fn $main(level: &str) {
+                let m128 = f32x2(1., 2.);
+                let m256 = f32x4(3., 4., 5., 6.);
+                let m512 = f32x8(7., 8., 9., 10., 11., 12., 13., 14.);
+                assert_eq!(id_sse_128(m128), m128);
+                assert_eq!(id_sse_256(m256), m256);
+                assert_eq!(id_sse_512(m512), m512);
+
+                if level == "sse" {
+                    return
+                }
+                assert_eq!(id_avx_128(m128), m128);
+                assert_eq!(id_avx_256(m256), m256);
+                assert_eq!(id_avx_512(m512), m512);
+
+                if level == "avx" {
+                    return
+                }
+                assert_eq!(id_avx512_128(m128), m128);
+                assert_eq!(id_avx512_256(m256), m256);
+                assert_eq!(id_avx512_512(m512), m512);
+            }
+        )*)
+    }
+
+    mains! {
+        unsafe fn main_normal(level: &str) { ... }
+        #[target_feature(enable = "sse2")]
+        unsafe fn main_sse(level: &str) { ... }
+        #[target_feature(enable = "avx")]
+        unsafe fn main_avx(level: &str) { ... }
+        #[target_feature(enable = "avx512bw")]
+        unsafe fn main_avx512(level: &str) { ... }
+    }
+
+    #[target_feature(enable = "sse2")]
+    unsafe fn id_sse_128(a: f32x2) -> f32x2 {
+        assert_eq!(a, f32x2(1., 2.));
+        a.clone()
+    }
+
+    #[target_feature(enable = "sse2")]
+    unsafe fn id_sse_256(a: f32x4) -> f32x4 {
+        assert_eq!(a, f32x4(3., 4., 5., 6.));
+        a.clone()
+    }
+
+    #[target_feature(enable = "sse2")]
+    unsafe fn id_sse_512(a: f32x8) -> f32x8 {
+        assert_eq!(a, f32x8(7., 8., 9., 10., 11., 12., 13., 14.));
+        a.clone()
+    }
+
+    #[target_feature(enable = "avx")]
+    unsafe fn id_avx_128(a: f32x2) -> f32x2 {
+        assert_eq!(a, f32x2(1., 2.));
+        a.clone()
+    }
+
+    #[target_feature(enable = "avx")]
+    unsafe fn id_avx_256(a: f32x4) -> f32x4 {
+        assert_eq!(a, f32x4(3., 4., 5., 6.));
+        a.clone()
+    }
+
+    #[target_feature(enable = "avx")]
+    unsafe fn id_avx_512(a: f32x8) -> f32x8 {
+        assert_eq!(a, f32x8(7., 8., 9., 10., 11., 12., 13., 14.));
+        a.clone()
+    }
+
+    #[target_feature(enable = "avx512bw")]
+    unsafe fn id_avx512_128(a: f32x2) -> f32x2 {
+        assert_eq!(a, f32x2(1., 2.));
+        a.clone()
+    }
+
+    #[target_feature(enable = "avx512bw")]
+    unsafe fn id_avx512_256(a: f32x4) -> f32x4 {
+        assert_eq!(a, f32x4(3., 4., 5., 6.));
+        a.clone()
+    }
+
+    #[target_feature(enable = "avx512bw")]
+    unsafe fn id_avx512_512(a: f32x8) -> f32x8 {
+        assert_eq!(a, f32x8(7., 8., 9., 10., 11., 12., 13., 14.));
+        a.clone()
+    }
+}
+
+#[cfg(not(any(target_arch = "x86", target_arch = "x86_64")))]
+mod test {
+    pub fn main(level: &str) {}
+}
diff --git a/src/test/ui/abi/issues/issue-22565-rust-call.rs b/src/test/ui/abi/issues/issue-22565-rust-call.rs
index a08e0bfb5e5d..a572666c8887 100644
--- a/src/test/ui/abi/issues/issue-22565-rust-call.rs
+++ b/src/test/ui/abi/issues/issue-22565-rust-call.rs
@@ -1,32 +1,31 @@
 #![feature(unboxed_closures)]
 
 extern "rust-call" fn b(_i: i32) {}
-//~^ ERROR functions with the "rust-call" ABI must take a single non-self argument that is a tuple
+//~^ ERROR functions with the "rust-call" ABI must take a single non-self tuple argument
 
 trait Tr {
     extern "rust-call" fn a();
+    //~^ ERROR functions with the "rust-call" ABI must take a single non-self tuple argument
 
     extern "rust-call" fn b() {}
-    //~^ ERROR functions with the "rust-call" ABI must take a single non-self argument
+    //~^ ERROR functions with the "rust-call" ABI must take a single non-self tuple argument
 }
 
 struct Foo;
 
 impl Foo {
     extern "rust-call" fn bar() {}
-    //~^ ERROR functions with the "rust-call" ABI must take a single non-self argument
+    //~^ ERROR functions with the "rust-call" ABI must take a single non-self tuple argument
 }
 
 impl Tr for Foo {
     extern "rust-call" fn a() {}
-    //~^ ERROR functions with the "rust-call" ABI must take a single non-self argument
+    //~^ ERROR functions with the "rust-call" ABI must take a single non-self tuple argument
 }
 
-fn main () {
+fn main() {
     b(10);
-
     Foo::bar();
-
     <Foo as Tr>::a();
     <Foo as Tr>::b();
 }
diff --git a/src/test/ui/abi/issues/issue-22565-rust-call.stderr b/src/test/ui/abi/issues/issue-22565-rust-call.stderr
index 3eee10bc5e95..9d205b444fad 100644
--- a/src/test/ui/abi/issues/issue-22565-rust-call.stderr
+++ b/src/test/ui/abi/issues/issue-22565-rust-call.stderr
@@ -1,26 +1,33 @@
-error: functions with the "rust-call" ABI must take a single non-self argument that is a tuple
+error[E0277]: functions with the "rust-call" ABI must take a single non-self tuple argument
   --> $DIR/issue-22565-rust-call.rs:3:1
    |
 LL | extern "rust-call" fn b(_i: i32) {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Tuple` is not implemented for `i32`
 
-error: functions with the "rust-call" ABI must take a single non-self argument that is a tuple
-  --> $DIR/issue-22565-rust-call.rs:9:5
-   |
-LL |     extern "rust-call" fn b() {}
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
-
-error: functions with the "rust-call" ABI must take a single non-self argument that is a tuple
-  --> $DIR/issue-22565-rust-call.rs:16:5
+error: functions with the "rust-call" ABI must take a single non-self tuple argument
+  --> $DIR/issue-22565-rust-call.rs:17:5
    |
 LL |     extern "rust-call" fn bar() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: functions with the "rust-call" ABI must take a single non-self argument that is a tuple
-  --> $DIR/issue-22565-rust-call.rs:21:5
+error: functions with the "rust-call" ABI must take a single non-self tuple argument
+  --> $DIR/issue-22565-rust-call.rs:22:5
    |
 LL |     extern "rust-call" fn a() {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: aborting due to 4 previous errors
+error: functions with the "rust-call" ABI must take a single non-self tuple argument
+  --> $DIR/issue-22565-rust-call.rs:7:5
+   |
+LL |     extern "rust-call" fn a();
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
 
+error: functions with the "rust-call" ABI must take a single non-self tuple argument
+  --> $DIR/issue-22565-rust-call.rs:10:5
+   |
+LL |     extern "rust-call" fn b() {}
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to 5 previous errors
+
+For more information about this error, try `rustc --explain E0277`.
diff --git a/src/test/ui/abi/rustcall-generic.rs b/src/test/ui/abi/rustcall-generic.rs
index 411c98e10313..6eaccc436b69 100644
--- a/src/test/ui/abi/rustcall-generic.rs
+++ b/src/test/ui/abi/rustcall-generic.rs
@@ -2,9 +2,9 @@
 // check-pass
 //[opt] compile-flags: -Zmir-opt-level=3
 
-#![feature(unboxed_closures)]
+#![feature(unboxed_closures, tuple_trait)]
 
-extern "rust-call" fn foo<T>(_: T) {}
+extern "rust-call" fn foo<T: std::marker::Tuple>(_: T) {}
 
 fn main() {
     foo(());
diff --git a/src/test/ui/alloc-error/alloc-error-handler-bad-signature-1.rs b/src/test/ui/alloc-error/alloc-error-handler-bad-signature-1.rs
index 41c9a265cd7b..cd06423e3a55 100644
--- a/src/test/ui/alloc-error/alloc-error-handler-bad-signature-1.rs
+++ b/src/test/ui/alloc-error/alloc-error-handler-bad-signature-1.rs
@@ -8,8 +8,8 @@ use core::alloc::Layout;
 
 #[alloc_error_handler]
 fn oom(
-    info: &Layout, //~ ERROR argument should be `Layout`
-) -> () //~ ERROR return type should be `!`
+    info: &Layout, //~^ ERROR mismatched types
+) -> () //~^^ ERROR mismatched types
 {
     loop {}
 }
diff --git a/src/test/ui/alloc-error/alloc-error-handler-bad-signature-1.stderr b/src/test/ui/alloc-error/alloc-error-handler-bad-signature-1.stderr
index 34e09da45ad5..d0911fa3985d 100644
--- a/src/test/ui/alloc-error/alloc-error-handler-bad-signature-1.stderr
+++ b/src/test/ui/alloc-error/alloc-error-handler-bad-signature-1.stderr
@@ -1,14 +1,50 @@
-error: return type should be `!`
-  --> $DIR/alloc-error-handler-bad-signature-1.rs:12:6
+error[E0308]: mismatched types
+  --> $DIR/alloc-error-handler-bad-signature-1.rs:10:1
    |
-LL | ) -> ()
-   |      ^^
-
-error: argument should be `Layout`
-  --> $DIR/alloc-error-handler-bad-signature-1.rs:11:11
+LL |    #[alloc_error_handler]
+   |    ---------------------- in this procedural macro expansion
+LL |    fn oom(
+   |   _^
+   |  |_|
+   | ||
+LL | ||     info: &Layout,
+LL | || ) -> ()
+   | ||_______- arguments to this function are incorrect
+LL | |  {
+LL | |      loop {}
+LL | |  }
+   | |__^ expected `&Layout`, found struct `Layout`
    |
+note: function defined here
+  --> $DIR/alloc-error-handler-bad-signature-1.rs:10:4
+   |
+LL | fn oom(
+   |    ^^^
 LL |     info: &Layout,
-   |           ^^^^^^^
+   |     -------------
+   = note: this error originates in the attribute macro `alloc_error_handler` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error[E0308]: mismatched types
+  --> $DIR/alloc-error-handler-bad-signature-1.rs:10:1
+   |
+LL |    #[alloc_error_handler]
+   |    ---------------------- in this procedural macro expansion
+LL |    fn oom(
+   |   _^
+   |  |_|
+   | ||
+LL | ||     info: &Layout,
+LL | || ) -> ()
+   | ||_______^ expected `!`, found `()`
+LL | |  {
+LL | |      loop {}
+LL | |  }
+   | |__- expected `!` because of return type
+   |
+   = note:   expected type `!`
+           found unit type `()`
+   = note: this error originates in the attribute macro `alloc_error_handler` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to 2 previous errors
 
+For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/ui/alloc-error/alloc-error-handler-bad-signature-2.rs b/src/test/ui/alloc-error/alloc-error-handler-bad-signature-2.rs
index 49ea3105fbd7..4f76257fc726 100644
--- a/src/test/ui/alloc-error/alloc-error-handler-bad-signature-2.rs
+++ b/src/test/ui/alloc-error/alloc-error-handler-bad-signature-2.rs
@@ -8,8 +8,8 @@ struct Layout;
 
 #[alloc_error_handler]
 fn oom(
-    info: Layout, //~ ERROR argument should be `Layout`
-) { //~ ERROR return type should be `!`
+    info: Layout, //~^ ERROR mismatched types
+) { //~^^ ERROR mismatched types
     loop {}
 }
 
diff --git a/src/test/ui/alloc-error/alloc-error-handler-bad-signature-2.stderr b/src/test/ui/alloc-error/alloc-error-handler-bad-signature-2.stderr
index 85544b0c3849..5777279855d9 100644
--- a/src/test/ui/alloc-error/alloc-error-handler-bad-signature-2.stderr
+++ b/src/test/ui/alloc-error/alloc-error-handler-bad-signature-2.stderr
@@ -1,14 +1,63 @@
-error: return type should be `!`
-  --> $DIR/alloc-error-handler-bad-signature-2.rs:12:3
+error[E0308]: mismatched types
+  --> $DIR/alloc-error-handler-bad-signature-2.rs:10:1
    |
-LL | ) {
-   |   ^
-
-error: argument should be `Layout`
-  --> $DIR/alloc-error-handler-bad-signature-2.rs:11:11
+LL |    #[alloc_error_handler]
+   |    ---------------------- in this procedural macro expansion
+LL |    fn oom(
+   |   _^
+   |  |_|
+   | ||
+LL | ||     info: Layout,
+LL | || ) {
+   | || -
+   | ||_|
+   | |  arguments to this function are incorrect
+LL | |      loop {}
+LL | |  }
+   | |__^ expected struct `Layout`, found struct `core::alloc::Layout`
    |
+   = note: struct `core::alloc::Layout` and struct `Layout` have similar names, but are actually distinct types
+note: struct `core::alloc::Layout` is defined in crate `core`
+  --> $SRC_DIR/core/src/alloc/layout.rs:LL:COL
+   |
+LL | pub struct Layout {
+   | ^^^^^^^^^^^^^^^^^
+note: struct `Layout` is defined in the current crate
+  --> $DIR/alloc-error-handler-bad-signature-2.rs:7:1
+   |
+LL | struct Layout;
+   | ^^^^^^^^^^^^^
+note: function defined here
+  --> $DIR/alloc-error-handler-bad-signature-2.rs:10:4
+   |
+LL | fn oom(
+   |    ^^^
 LL |     info: Layout,
-   |           ^^^^^^
+   |     ------------
+   = note: this error originates in the attribute macro `alloc_error_handler` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error[E0308]: mismatched types
+  --> $DIR/alloc-error-handler-bad-signature-2.rs:10:1
+   |
+LL |    #[alloc_error_handler]
+   |    ---------------------- in this procedural macro expansion
+LL |    fn oom(
+   |   _^
+   |  |_|
+   | ||
+LL | ||     info: Layout,
+LL | || ) {
+   | || ^
+   | ||_|
+   | |  expected `!`, found `()`
+LL | |      loop {}
+LL | |  }
+   | |__- expected `!` because of return type
+   |
+   = note:   expected type `!`
+           found unit type `()`
+   = note: this error originates in the attribute macro `alloc_error_handler` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to 2 previous errors
 
+For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/ui/alloc-error/alloc-error-handler-bad-signature-3.rs b/src/test/ui/alloc-error/alloc-error-handler-bad-signature-3.rs
index 321fd954db6d..8430fabe84d0 100644
--- a/src/test/ui/alloc-error/alloc-error-handler-bad-signature-3.rs
+++ b/src/test/ui/alloc-error/alloc-error-handler-bad-signature-3.rs
@@ -7,7 +7,7 @@
 struct Layout;
 
 #[alloc_error_handler]
-fn oom() -> ! { //~ ERROR function should have one argument
+fn oom() -> ! { //~ ERROR this function takes 0 arguments but 1 argument was supplied
     loop {}
 }
 
diff --git a/src/test/ui/alloc-error/alloc-error-handler-bad-signature-3.stderr b/src/test/ui/alloc-error/alloc-error-handler-bad-signature-3.stderr
index 8575e7508f12..77ea8ef05209 100644
--- a/src/test/ui/alloc-error/alloc-error-handler-bad-signature-3.stderr
+++ b/src/test/ui/alloc-error/alloc-error-handler-bad-signature-3.stderr
@@ -1,8 +1,25 @@
-error: function should have one argument
+error[E0061]: this function takes 0 arguments but 1 argument was supplied
   --> $DIR/alloc-error-handler-bad-signature-3.rs:10:1
    |
+LL |   #[alloc_error_handler]
+   |   ---------------------- in this procedural macro expansion
+LL |   fn oom() -> ! {
+   |  _-^^^^^^^^^^^^
+LL | |     loop {}
+LL | | }
+   | |_- argument of type `core::alloc::Layout` unexpected
+   |
+note: function defined here
+  --> $DIR/alloc-error-handler-bad-signature-3.rs:10:4
+   |
 LL | fn oom() -> ! {
-   | ^^^^^^^^^^^^^
+   |    ^^^
+   = note: this error originates in the attribute macro `alloc_error_handler` (in Nightly builds, run with -Z macro-backtrace for more info)
+help: remove the extra argument
+   |
+LL | fn oom() -> !() {
+   |              ++
 
 error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0061`.
diff --git a/src/test/ui/argument-suggestions/formal-and-expected-differ.rs b/src/test/ui/argument-suggestions/formal-and-expected-differ.rs
new file mode 100644
index 000000000000..5e3b55ca5258
--- /dev/null
+++ b/src/test/ui/argument-suggestions/formal-and-expected-differ.rs
@@ -0,0 +1,25 @@
+pub trait Foo {
+    type T;
+}
+
+impl Foo for i32 {
+    type T = f32;
+}
+
+pub struct U<T1, T2>(T1, S<T2>)
+where
+    T1: Foo<T = T2>;
+
+pub struct S<T>(T);
+
+fn main() {
+    // The error message here isn't great -- it has to do with the fact that the
+    // `expected_inputs_for_expected_output` deduced inputs differs from the inputs
+    // that we infer from the constraints of the signature.
+    //
+    // I am not really sure what the best way of presenting this error message is,
+    // since right now it just suggests changing `3u32` <=> `3f32` back and forth.
+    let _: U<_, u32> = U(1, S(3u32));
+    //~^ ERROR mismatched types
+    //~| ERROR mismatched types
+}
diff --git a/src/test/ui/argument-suggestions/formal-and-expected-differ.stderr b/src/test/ui/argument-suggestions/formal-and-expected-differ.stderr
new file mode 100644
index 000000000000..905875b52776
--- /dev/null
+++ b/src/test/ui/argument-suggestions/formal-and-expected-differ.stderr
@@ -0,0 +1,30 @@
+error[E0308]: mismatched types
+  --> $DIR/formal-and-expected-differ.rs:22:29
+   |
+LL |     let _: U<_, u32> = U(1, S(3u32));
+   |                        -    ^^^^^^^ expected `f32`, found `u32`
+   |                        |
+   |                        arguments to this struct are incorrect
+   |
+   = note: expected struct `S<f32>`
+              found struct `S<u32>`
+note: tuple struct defined here
+  --> $DIR/formal-and-expected-differ.rs:9:12
+   |
+LL | pub struct U<T1, T2>(T1, S<T2>)
+   |            ^
+
+error[E0308]: mismatched types
+  --> $DIR/formal-and-expected-differ.rs:22:24
+   |
+LL |     let _: U<_, u32> = U(1, S(3u32));
+   |            ---------   ^^^^^^^^^^^^^ expected `u32`, found `f32`
+   |            |
+   |            expected due to this
+   |
+   = note: expected struct `U<_, u32>`
+              found struct `U<i32, f32>`
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/ui/array-slice-vec/array-break-length.stderr b/src/test/ui/array-slice-vec/array-break-length.stderr
index 93f1c238bcc4..2df7b6d7f63c 100644
--- a/src/test/ui/array-slice-vec/array-break-length.stderr
+++ b/src/test/ui/array-slice-vec/array-break-length.stderr
@@ -1,8 +1,8 @@
-error[E0268]: `break` outside of a loop
+error[E0268]: `break` outside of a loop or labeled block
   --> $DIR/array-break-length.rs:3:17
    |
 LL |         |_: [_; break]| {}
-   |                 ^^^^^ cannot `break` outside of a loop
+   |                 ^^^^^ cannot `break` outside of a loop or labeled block
 
 error[E0268]: `continue` outside of a loop
   --> $DIR/array-break-length.rs:7:17
diff --git a/src/test/ui/array-slice-vec/vec-macro-with-comma-only.stderr b/src/test/ui/array-slice-vec/vec-macro-with-comma-only.stderr
index abbee347c00b..ec4a001f4d01 100644
--- a/src/test/ui/array-slice-vec/vec-macro-with-comma-only.stderr
+++ b/src/test/ui/array-slice-vec/vec-macro-with-comma-only.stderr
@@ -3,6 +3,8 @@ error: no rules expected the token `,`
    |
 LL |     vec![,];
    |          ^ no rules expected this token in macro call
+   |
+   = note: while trying to match end of macro
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/asm/aarch64/llvm-58384.rs b/src/test/ui/asm/aarch64/llvm-58384.rs
new file mode 100644
index 000000000000..308f78908295
--- /dev/null
+++ b/src/test/ui/asm/aarch64/llvm-58384.rs
@@ -0,0 +1,16 @@
+// only-aarch64
+// run-pass
+// needs-asm-support
+
+// Test that we properly work around this LLVM issue:
+// https://github.com/llvm/llvm-project/issues/58384
+
+use std::arch::asm;
+
+fn main() {
+    let a: i32;
+    unsafe {
+        asm!("", inout("x0") 435 => a);
+    }
+    assert_eq!(a, 435);
+}
diff --git a/src/test/ui/asm/issue-92378.rs b/src/test/ui/asm/issue-92378.rs
index 6e3c26e98c3f..809b0d1555ae 100644
--- a/src/test/ui/asm/issue-92378.rs
+++ b/src/test/ui/asm/issue-92378.rs
@@ -3,7 +3,7 @@
 // needs-asm-support
 // build-pass
 
-#![feature(no_core, lang_items, rustc_attrs, isa_attribute)]
+#![feature(no_core, lang_items, rustc_attrs)]
 #![no_core]
 #![crate_type = "rlib"]
 
diff --git a/src/test/ui/asm/naked-invalid-attr.stderr b/src/test/ui/asm/naked-invalid-attr.stderr
index 58344be93346..e8ddccc854ab 100644
--- a/src/test/ui/asm/naked-invalid-attr.stderr
+++ b/src/test/ui/asm/naked-invalid-attr.stderr
@@ -36,7 +36,7 @@ error: attribute should be applied to a function definition
   --> $DIR/naked-invalid-attr.rs:5:1
    |
 LL | #![naked]
-   | ^^^^^^^^^
+   | ^^^^^^^^^ cannot be applied to crates
 
 error: aborting due to 5 previous errors
 
diff --git a/src/test/ui/assoc-inherent.rs b/src/test/ui/assoc-inherent.rs
deleted file mode 100644
index c579c962ffcc..000000000000
--- a/src/test/ui/assoc-inherent.rs
+++ /dev/null
@@ -1,20 +0,0 @@
-// Test that inherent associated types work with
-// inherent_associated_types feature gate.
-
-#![feature(inherent_associated_types)]
-#![allow(incomplete_features)]
-
-struct Foo;
-
-impl Foo {
-    type Bar = isize;
-}
-
-impl Foo {
-    type Baz; //~ ERROR associated type in `impl` without body
-}
-
-fn main() {
-    let x : Foo::Bar; //~ERROR ambiguous associated type
-    x = 0isize;
-}
diff --git a/src/test/ui/assoc-inherent.stderr b/src/test/ui/assoc-inherent.stderr
deleted file mode 100644
index b703453fa033..000000000000
--- a/src/test/ui/assoc-inherent.stderr
+++ /dev/null
@@ -1,17 +0,0 @@
-error: associated type in `impl` without body
-  --> $DIR/assoc-inherent.rs:14:5
-   |
-LL |     type Baz;
-   |     ^^^^^^^^-
-   |             |
-   |             help: provide a definition for the type: `= <type>;`
-
-error[E0223]: ambiguous associated type
-  --> $DIR/assoc-inherent.rs:18:13
-   |
-LL |     let x : Foo::Bar;
-   |             ^^^^^^^^ help: use fully-qualified syntax: `<Foo as Trait>::Bar`
-
-error: aborting due to 2 previous errors
-
-For more information about this error, try `rustc --explain E0223`.
diff --git a/src/test/ui/associated-inherent-types/assoc-inherent-no-body.rs b/src/test/ui/associated-inherent-types/assoc-inherent-no-body.rs
new file mode 100644
index 000000000000..71f65b92eae2
--- /dev/null
+++ b/src/test/ui/associated-inherent-types/assoc-inherent-no-body.rs
@@ -0,0 +1,10 @@
+#![feature(inherent_associated_types)]
+#![allow(incomplete_features)]
+
+struct Foo;
+
+impl Foo {
+    type Baz; //~ ERROR associated type in `impl` without body
+}
+
+fn main() {}
diff --git a/src/test/ui/associated-inherent-types/assoc-inherent-no-body.stderr b/src/test/ui/associated-inherent-types/assoc-inherent-no-body.stderr
new file mode 100644
index 000000000000..387a5658da37
--- /dev/null
+++ b/src/test/ui/associated-inherent-types/assoc-inherent-no-body.stderr
@@ -0,0 +1,10 @@
+error: associated type in `impl` without body
+  --> $DIR/assoc-inherent-no-body.rs:7:5
+   |
+LL |     type Baz;
+   |     ^^^^^^^^-
+   |             |
+   |             help: provide a definition for the type: `= <type>;`
+
+error: aborting due to previous error
+
diff --git a/src/test/ui/associated-inherent-types/assoc-inherent-use.rs b/src/test/ui/associated-inherent-types/assoc-inherent-use.rs
new file mode 100644
index 000000000000..7ae425e2aaaf
--- /dev/null
+++ b/src/test/ui/associated-inherent-types/assoc-inherent-use.rs
@@ -0,0 +1,14 @@
+// check-pass
+#![feature(inherent_associated_types)]
+#![allow(incomplete_features)]
+
+struct Foo;
+
+impl Foo {
+    type Bar = isize;
+}
+
+fn main() {
+    let x: Foo::Bar;
+    x = 0isize;
+}
diff --git a/src/test/ui/associated-type-bounds/duplicate.rs b/src/test/ui/associated-type-bounds/duplicate.rs
index 6e464f69510e..f67410986e55 100644
--- a/src/test/ui/associated-type-bounds/duplicate.rs
+++ b/src/test/ui/associated-type-bounds/duplicate.rs
@@ -132,12 +132,15 @@ where
 }
 
 fn FRPIT1() -> impl Iterator<Item: Copy, Item: Send> {
+    //~^ ERROR the value of the associated type `Item` (from trait `Iterator`) is already specified [E0719]
     iter::empty()
 }
 fn FRPIT2() -> impl Iterator<Item: Copy, Item: Copy> {
+    //~^ ERROR the value of the associated type `Item` (from trait `Iterator`) is already specified [E0719]
     iter::empty()
 }
 fn FRPIT3() -> impl Iterator<Item: 'static, Item: 'static> {
+    //~^ ERROR the value of the associated type `Item` (from trait `Iterator`) is already specified [E0719]
     iter::empty()
 }
 fn FAPIT1(_: impl Iterator<Item: Copy, Item: Send>) {}
diff --git a/src/test/ui/associated-type-bounds/duplicate.stderr b/src/test/ui/associated-type-bounds/duplicate.stderr
index e4f4836f71ab..c3061327f566 100644
--- a/src/test/ui/associated-type-bounds/duplicate.stderr
+++ b/src/test/ui/associated-type-bounds/duplicate.stderr
@@ -191,7 +191,31 @@ LL |     T: Iterator<Item: 'static, Item: 'static>,
    |                 `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:143:40
+  --> $DIR/duplicate.rs:134:42
+   |
+LL | fn FRPIT1() -> impl Iterator<Item: Copy, Item: Send> {
+   |                              ----------  ^^^^^^^^^^ re-bound here
+   |                              |
+   |                              `Item` bound here first
+
+error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
+  --> $DIR/duplicate.rs:138:42
+   |
+LL | fn FRPIT2() -> impl Iterator<Item: Copy, Item: Copy> {
+   |                              ----------  ^^^^^^^^^^ re-bound here
+   |                              |
+   |                              `Item` bound here first
+
+error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
+  --> $DIR/duplicate.rs:142:45
+   |
+LL | fn FRPIT3() -> impl Iterator<Item: 'static, Item: 'static> {
+   |                              -------------  ^^^^^^^^^^^^^ re-bound here
+   |                              |
+   |                              `Item` bound here first
+
+error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
+  --> $DIR/duplicate.rs:146:40
    |
 LL | fn FAPIT1(_: impl Iterator<Item: Copy, Item: Send>) {}
    |                            ----------  ^^^^^^^^^^ re-bound here
@@ -199,7 +223,7 @@ LL | fn FAPIT1(_: impl Iterator<Item: Copy, Item: Send>) {}
    |                            `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:145:40
+  --> $DIR/duplicate.rs:148:40
    |
 LL | fn FAPIT2(_: impl Iterator<Item: Copy, Item: Copy>) {}
    |                            ----------  ^^^^^^^^^^ re-bound here
@@ -207,7 +231,7 @@ LL | fn FAPIT2(_: impl Iterator<Item: Copy, Item: Copy>) {}
    |                            `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:147:43
+  --> $DIR/duplicate.rs:150:43
    |
 LL | fn FAPIT3(_: impl Iterator<Item: 'static, Item: 'static>) {}
    |                            -------------  ^^^^^^^^^^^^^ re-bound here
@@ -215,7 +239,7 @@ LL | fn FAPIT3(_: impl Iterator<Item: 'static, Item: 'static>) {}
    |                            `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:150:35
+  --> $DIR/duplicate.rs:153:35
    |
 LL | type TAI1<T: Iterator<Item: Copy, Item: Send>> = T;
    |                       ----------  ^^^^^^^^^^ re-bound here
@@ -223,7 +247,7 @@ LL | type TAI1<T: Iterator<Item: Copy, Item: Send>> = T;
    |                       `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:152:35
+  --> $DIR/duplicate.rs:155:35
    |
 LL | type TAI2<T: Iterator<Item: Copy, Item: Copy>> = T;
    |                       ----------  ^^^^^^^^^^ re-bound here
@@ -231,7 +255,7 @@ LL | type TAI2<T: Iterator<Item: Copy, Item: Copy>> = T;
    |                       `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:154:38
+  --> $DIR/duplicate.rs:157:38
    |
 LL | type TAI3<T: Iterator<Item: 'static, Item: 'static>> = T;
    |                       -------------  ^^^^^^^^^^^^^ re-bound here
@@ -239,7 +263,7 @@ LL | type TAI3<T: Iterator<Item: 'static, Item: 'static>> = T;
    |                       `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:158:29
+  --> $DIR/duplicate.rs:161:29
    |
 LL |     T: Iterator<Item: Copy, Item: Send>,
    |                 ----------  ^^^^^^^^^^ re-bound here
@@ -247,7 +271,7 @@ LL |     T: Iterator<Item: Copy, Item: Send>,
    |                 `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:163:29
+  --> $DIR/duplicate.rs:166:29
    |
 LL |     T: Iterator<Item: Copy, Item: Copy>,
    |                 ----------  ^^^^^^^^^^ re-bound here
@@ -255,7 +279,7 @@ LL |     T: Iterator<Item: Copy, Item: Copy>,
    |                 `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:168:32
+  --> $DIR/duplicate.rs:171:32
    |
 LL |     T: Iterator<Item: 'static, Item: 'static>,
    |                 -------------  ^^^^^^^^^^^^^ re-bound here
@@ -263,7 +287,7 @@ LL |     T: Iterator<Item: 'static, Item: 'static>,
    |                 `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:172:36
+  --> $DIR/duplicate.rs:175:36
    |
 LL | type ETAI1<T: Iterator<Item: Copy, Item: Send>> = impl Copy;
    |                        ----------  ^^^^^^^^^^ re-bound here
@@ -271,7 +295,7 @@ LL | type ETAI1<T: Iterator<Item: Copy, Item: Send>> = impl Copy;
    |                        `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:174:36
+  --> $DIR/duplicate.rs:177:36
    |
 LL | type ETAI2<T: Iterator<Item: Copy, Item: Copy>> = impl Copy;
    |                        ----------  ^^^^^^^^^^ re-bound here
@@ -279,7 +303,7 @@ LL | type ETAI2<T: Iterator<Item: Copy, Item: Copy>> = impl Copy;
    |                        `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:176:39
+  --> $DIR/duplicate.rs:179:39
    |
 LL | type ETAI3<T: Iterator<Item: 'static, Item: 'static>> = impl Copy;
    |                        -------------  ^^^^^^^^^^^^^ re-bound here
@@ -287,7 +311,7 @@ LL | type ETAI3<T: Iterator<Item: 'static, Item: 'static>> = impl Copy;
    |                        `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:178:40
+  --> $DIR/duplicate.rs:181:40
    |
 LL | type ETAI4 = impl Iterator<Item: Copy, Item: Send>;
    |                            ----------  ^^^^^^^^^^ re-bound here
@@ -295,7 +319,7 @@ LL | type ETAI4 = impl Iterator<Item: Copy, Item: Send>;
    |                            `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:180:40
+  --> $DIR/duplicate.rs:183:40
    |
 LL | type ETAI5 = impl Iterator<Item: Copy, Item: Copy>;
    |                            ----------  ^^^^^^^^^^ re-bound here
@@ -303,7 +327,7 @@ LL | type ETAI5 = impl Iterator<Item: Copy, Item: Copy>;
    |                            `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:182:43
+  --> $DIR/duplicate.rs:185:43
    |
 LL | type ETAI6 = impl Iterator<Item: 'static, Item: 'static>;
    |                            -------------  ^^^^^^^^^^^^^ re-bound here
@@ -311,7 +335,7 @@ LL | type ETAI6 = impl Iterator<Item: 'static, Item: 'static>;
    |                            `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:185:36
+  --> $DIR/duplicate.rs:188:36
    |
 LL | trait TRI1<T: Iterator<Item: Copy, Item: Send>> {}
    |                        ----------  ^^^^^^^^^^ re-bound here
@@ -319,7 +343,7 @@ LL | trait TRI1<T: Iterator<Item: Copy, Item: Send>> {}
    |                        `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:187:36
+  --> $DIR/duplicate.rs:190:36
    |
 LL | trait TRI2<T: Iterator<Item: Copy, Item: Copy>> {}
    |                        ----------  ^^^^^^^^^^ re-bound here
@@ -327,7 +351,7 @@ LL | trait TRI2<T: Iterator<Item: Copy, Item: Copy>> {}
    |                        `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:189:39
+  --> $DIR/duplicate.rs:192:39
    |
 LL | trait TRI3<T: Iterator<Item: 'static, Item: 'static>> {}
    |                        -------------  ^^^^^^^^^^^^^ re-bound here
@@ -335,7 +359,7 @@ LL | trait TRI3<T: Iterator<Item: 'static, Item: 'static>> {}
    |                        `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:191:34
+  --> $DIR/duplicate.rs:194:34
    |
 LL | trait TRS1: Iterator<Item: Copy, Item: Send> {}
    |                      ----------  ^^^^^^^^^^ re-bound here
@@ -343,7 +367,7 @@ LL | trait TRS1: Iterator<Item: Copy, Item: Send> {}
    |                      `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:193:34
+  --> $DIR/duplicate.rs:196:34
    |
 LL | trait TRS2: Iterator<Item: Copy, Item: Copy> {}
    |                      ----------  ^^^^^^^^^^ re-bound here
@@ -351,7 +375,7 @@ LL | trait TRS2: Iterator<Item: Copy, Item: Copy> {}
    |                      `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:195:37
+  --> $DIR/duplicate.rs:198:37
    |
 LL | trait TRS3: Iterator<Item: 'static, Item: 'static> {}
    |                      -------------  ^^^^^^^^^^^^^ re-bound here
@@ -359,7 +383,7 @@ LL | trait TRS3: Iterator<Item: 'static, Item: 'static> {}
    |                      `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:199:29
+  --> $DIR/duplicate.rs:202:29
    |
 LL |     T: Iterator<Item: Copy, Item: Send>,
    |                 ----------  ^^^^^^^^^^ re-bound here
@@ -367,7 +391,7 @@ LL |     T: Iterator<Item: Copy, Item: Send>,
    |                 `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:205:29
+  --> $DIR/duplicate.rs:208:29
    |
 LL |     T: Iterator<Item: Copy, Item: Copy>,
    |                 ----------  ^^^^^^^^^^ re-bound here
@@ -375,7 +399,7 @@ LL |     T: Iterator<Item: Copy, Item: Copy>,
    |                 `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:211:32
+  --> $DIR/duplicate.rs:214:32
    |
 LL |     T: Iterator<Item: 'static, Item: 'static>,
    |                 -------------  ^^^^^^^^^^^^^ re-bound here
@@ -383,7 +407,7 @@ LL |     T: Iterator<Item: 'static, Item: 'static>,
    |                 `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:217:32
+  --> $DIR/duplicate.rs:220:32
    |
 LL |     Self: Iterator<Item: Copy, Item: Send>,
    |                    ----------  ^^^^^^^^^^ re-bound here
@@ -391,7 +415,7 @@ LL |     Self: Iterator<Item: Copy, Item: Send>,
    |                    `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:217:32
+  --> $DIR/duplicate.rs:220:32
    |
 LL |     Self: Iterator<Item: Copy, Item: Send>,
    |                    ----------  ^^^^^^^^^^ re-bound here
@@ -399,7 +423,7 @@ LL |     Self: Iterator<Item: Copy, Item: Send>,
    |                    `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:224:32
+  --> $DIR/duplicate.rs:227:32
    |
 LL |     Self: Iterator<Item: Copy, Item: Copy>,
    |                    ----------  ^^^^^^^^^^ re-bound here
@@ -407,7 +431,7 @@ LL |     Self: Iterator<Item: Copy, Item: Copy>,
    |                    `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:224:32
+  --> $DIR/duplicate.rs:227:32
    |
 LL |     Self: Iterator<Item: Copy, Item: Copy>,
    |                    ----------  ^^^^^^^^^^ re-bound here
@@ -415,7 +439,7 @@ LL |     Self: Iterator<Item: Copy, Item: Copy>,
    |                    `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:231:35
+  --> $DIR/duplicate.rs:234:35
    |
 LL |     Self: Iterator<Item: 'static, Item: 'static>,
    |                    -------------  ^^^^^^^^^^^^^ re-bound here
@@ -423,7 +447,7 @@ LL |     Self: Iterator<Item: 'static, Item: 'static>,
    |                    `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:231:35
+  --> $DIR/duplicate.rs:234:35
    |
 LL |     Self: Iterator<Item: 'static, Item: 'static>,
    |                    -------------  ^^^^^^^^^^^^^ re-bound here
@@ -431,7 +455,7 @@ LL |     Self: Iterator<Item: 'static, Item: 'static>,
    |                    `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:249:40
+  --> $DIR/duplicate.rs:252:40
    |
 LL | type TADyn1 = dyn Iterator<Item: Copy, Item: Send>;
    |                            ----------  ^^^^^^^^^^ re-bound here
@@ -439,7 +463,7 @@ LL | type TADyn1 = dyn Iterator<Item: Copy, Item: Send>;
    |                            `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:251:44
+  --> $DIR/duplicate.rs:254:44
    |
 LL | type TADyn2 = Box<dyn Iterator<Item: Copy, Item: Copy>>;
    |                                ----------  ^^^^^^^^^^ re-bound here
@@ -447,7 +471,7 @@ LL | type TADyn2 = Box<dyn Iterator<Item: Copy, Item: Copy>>;
    |                                `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:253:43
+  --> $DIR/duplicate.rs:256:43
    |
 LL | type TADyn3 = dyn Iterator<Item: 'static, Item: 'static>;
    |                            -------------  ^^^^^^^^^^^^^ re-bound here
@@ -455,7 +479,7 @@ LL | type TADyn3 = dyn Iterator<Item: 'static, Item: 'static>;
    |                            `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:237:34
+  --> $DIR/duplicate.rs:240:34
    |
 LL |     type A: Iterator<Item: Copy, Item: Send>;
    |                      ----------  ^^^^^^^^^^ re-bound here
@@ -463,7 +487,7 @@ LL |     type A: Iterator<Item: Copy, Item: Send>;
    |                      `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:241:34
+  --> $DIR/duplicate.rs:244:34
    |
 LL |     type A: Iterator<Item: Copy, Item: Copy>;
    |                      ----------  ^^^^^^^^^^ re-bound here
@@ -471,13 +495,13 @@ LL |     type A: Iterator<Item: Copy, Item: Copy>;
    |                      `Item` bound here first
 
 error[E0719]: the value of the associated type `Item` (from trait `Iterator`) is already specified
-  --> $DIR/duplicate.rs:245:37
+  --> $DIR/duplicate.rs:248:37
    |
 LL |     type A: Iterator<Item: 'static, Item: 'static>;
    |                      -------------  ^^^^^^^^^^^^^ re-bound here
    |                      |
    |                      `Item` bound here first
 
-error: aborting due to 60 previous errors
+error: aborting due to 63 previous errors
 
 For more information about this error, try `rustc --explain E0719`.
diff --git a/src/test/ui/associated-types/cache/project-fn-ret-invariant.oneuse.stderr b/src/test/ui/associated-types/cache/project-fn-ret-invariant.oneuse.stderr
index cc1560162127..77841780f621 100644
--- a/src/test/ui/associated-types/cache/project-fn-ret-invariant.oneuse.stderr
+++ b/src/test/ui/associated-types/cache/project-fn-ret-invariant.oneuse.stderr
@@ -15,19 +15,19 @@ LL |     let a = bar(f, x);
    = help: see <https://doc.rust-lang.org/nomicon/subtyping.html> for more information about variance
 
 error: lifetime may not live long enough
-  --> $DIR/project-fn-ret-invariant.rs:40:13
+  --> $DIR/project-fn-ret-invariant.rs:42:13
    |
 LL | fn baz<'a, 'b>(x: Type<'a>, y: Type<'b>) -> (Type<'a>, Type<'b>) {
    |        --  -- lifetime `'b` defined here
    |        |
    |        lifetime `'a` defined here
-LL |     let f = foo; // <-- No consistent type can be inferred for `f` here.
-LL |     let a = bar(f, x);
+...
+LL |     let b = bar(f, y);
    |             ^^^^^^^^^ argument requires that `'b` must outlive `'a`
    |
    = help: consider adding the following bound: `'b: 'a`
-   = note: requirement occurs because of a function pointer to `foo`
-   = note: the function `foo` is invariant over the parameter `'a`
+   = note: requirement occurs because of the type `Type<'_>`, which makes the generic argument `'_` invariant
+   = note: the struct `Type<'a>` is invariant over the parameter `'a`
    = help: see <https://doc.rust-lang.org/nomicon/subtyping.html> for more information about variance
 
 help: `'a` and `'b` must be the same: replace one with the other
diff --git a/src/test/ui/associated-types/cache/project-fn-ret-invariant.rs b/src/test/ui/associated-types/cache/project-fn-ret-invariant.rs
index 1075fd6e0923..e043379133ab 100644
--- a/src/test/ui/associated-types/cache/project-fn-ret-invariant.rs
+++ b/src/test/ui/associated-types/cache/project-fn-ret-invariant.rs
@@ -39,8 +39,8 @@ fn baz<'a, 'b>(x: Type<'a>, y: Type<'b>) -> (Type<'a>, Type<'b>) {
     let f = foo; // <-- No consistent type can be inferred for `f` here.
     let a = bar(f, x);
     //[oneuse]~^ ERROR lifetime may not live long enough
-    //[oneuse]~| ERROR lifetime may not live long enough
     let b = bar(f, y);
+    //[oneuse]~^ ERROR lifetime may not live long enough
     (a, b)
 }
 
diff --git a/src/test/ui/async-await/async-fn-nonsend.stderr b/src/test/ui/async-await/async-fn-nonsend.stderr
index 40ad46b48620..a7b872fe4444 100644
--- a/src/test/ui/async-await/async-fn-nonsend.stderr
+++ b/src/test/ui/async-await/async-fn-nonsend.stderr
@@ -27,7 +27,7 @@ error: future cannot be sent between threads safely
 LL |     assert_send(non_sync_with_method_call());
    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ future returned by `non_sync_with_method_call` is not `Send`
    |
-   = help: the trait `Send` is not implemented for `dyn std::fmt::Write`
+   = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `dyn std::fmt::Write`
 note: future is not `Send` as this value is used across an await
   --> $DIR/async-fn-nonsend.rs:46:14
    |
diff --git a/src/test/ui/async-await/in-trait/async-associated-types.rs b/src/test/ui/async-await/in-trait/async-associated-types.rs
new file mode 100644
index 000000000000..a6f928f3b1ba
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/async-associated-types.rs
@@ -0,0 +1,24 @@
+// check-fail
+// known-bug: #102682
+// edition: 2021
+
+#![feature(async_fn_in_trait)]
+#![allow(incomplete_features)]
+
+use std::fmt::Debug;
+
+trait MyTrait<'a, 'b, T> where Self: 'a, T: Debug + Sized + 'b {
+    type MyAssoc;
+
+    async fn foo(&'a self, key: &'b T) -> Self::MyAssoc;
+}
+
+impl<'a, 'b, T: Debug + Sized + 'b, U: 'a> MyTrait<'a, 'b, T> for U {
+    type MyAssoc = (&'a U, &'b T);
+
+    async fn foo(&'a self, key: &'b T) -> (&'a U, &'b T) {
+        (self, key)
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/async-await/in-trait/async-associated-types.stderr b/src/test/ui/async-await/in-trait/async-associated-types.stderr
new file mode 100644
index 000000000000..0985150eee0d
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/async-associated-types.stderr
@@ -0,0 +1,57 @@
+error[E0495]: cannot infer an appropriate lifetime for lifetime parameter `'a` due to conflicting requirements
+  --> $DIR/async-associated-types.rs:19:43
+   |
+LL |     async fn foo(&'a self, key: &'b T) -> (&'a U, &'b T) {
+   |                                           ^^^^^^^^^^^^^^
+   |
+note: first, the lifetime cannot outlive the lifetime `'a` as defined here...
+  --> $DIR/async-associated-types.rs:16:6
+   |
+LL | impl<'a, 'b, T: Debug + Sized + 'b, U: 'a> MyTrait<'a, 'b, T> for U {
+   |      ^^
+note: ...so that the types are compatible
+  --> $DIR/async-associated-types.rs:19:43
+   |
+LL |     async fn foo(&'a self, key: &'b T) -> (&'a U, &'b T) {
+   |                                           ^^^^^^^^^^^^^^
+   = note: expected `(&'a U, &'b T)`
+              found `(&U, &T)`
+   = note: but, the lifetime must be valid for the static lifetime...
+note: ...so that the types are compatible
+  --> $DIR/async-associated-types.rs:19:43
+   |
+LL |     async fn foo(&'a self, key: &'b T) -> (&'a U, &'b T) {
+   |                                           ^^^^^^^^^^^^^^
+   = note: expected `MyTrait<'static, 'static, T>`
+              found `MyTrait<'_, '_, T>`
+
+error[E0495]: cannot infer an appropriate lifetime for lifetime parameter `'b` due to conflicting requirements
+  --> $DIR/async-associated-types.rs:19:43
+   |
+LL |     async fn foo(&'a self, key: &'b T) -> (&'a U, &'b T) {
+   |                                           ^^^^^^^^^^^^^^
+   |
+note: first, the lifetime cannot outlive the lifetime `'b` as defined here...
+  --> $DIR/async-associated-types.rs:16:10
+   |
+LL | impl<'a, 'b, T: Debug + Sized + 'b, U: 'a> MyTrait<'a, 'b, T> for U {
+   |          ^^
+note: ...so that the types are compatible
+  --> $DIR/async-associated-types.rs:19:43
+   |
+LL |     async fn foo(&'a self, key: &'b T) -> (&'a U, &'b T) {
+   |                                           ^^^^^^^^^^^^^^
+   = note: expected `(&'a U, &'b T)`
+              found `(&U, &T)`
+   = note: but, the lifetime must be valid for the static lifetime...
+note: ...so that the types are compatible
+  --> $DIR/async-associated-types.rs:19:43
+   |
+LL |     async fn foo(&'a self, key: &'b T) -> (&'a U, &'b T) {
+   |                                           ^^^^^^^^^^^^^^
+   = note: expected `MyTrait<'static, 'static, T>`
+              found `MyTrait<'_, '_, T>`
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0495`.
diff --git a/src/test/ui/async-await/in-trait/async-associated-types2.rs b/src/test/ui/async-await/in-trait/async-associated-types2.rs
new file mode 100644
index 000000000000..e546a0579c66
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/async-associated-types2.rs
@@ -0,0 +1,30 @@
+// check-pass
+// edition: 2021
+
+#![feature(async_fn_in_trait)]
+#![feature(type_alias_impl_trait)]
+#![allow(incomplete_features)]
+
+use std::future::Future;
+
+trait MyTrait {
+    type Fut<'a>: Future<Output = i32>
+    where
+        Self: 'a;
+
+    fn foo<'a>(&'a self) -> Self::Fut<'a>;
+}
+
+impl MyTrait for i32 {
+    type Fut<'a> = impl Future<Output = i32> + 'a
+    where
+        Self: 'a;
+
+    fn foo<'a>(&'a self) -> Self::Fut<'a> {
+        async {
+            *self
+        }
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/async-await/in-trait/async-example-desugared-boxed-in-trait.rs b/src/test/ui/async-await/in-trait/async-example-desugared-boxed-in-trait.rs
new file mode 100644
index 000000000000..38ba297189c6
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/async-example-desugared-boxed-in-trait.rs
@@ -0,0 +1,21 @@
+// edition: 2021
+
+#![feature(async_fn_in_trait)]
+#![feature(return_position_impl_trait_in_trait)]
+#![allow(incomplete_features)]
+
+use std::future::Future;
+use std::pin::Pin;
+
+trait MyTrait {
+    fn foo(&self) -> Pin<Box<dyn Future<Output = i32> + '_>>;
+}
+
+impl MyTrait for i32 {
+    async fn foo(&self) -> i32 {
+        //~^ ERROR method `foo` has an incompatible type for trait
+        *self
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/async-await/in-trait/async-example-desugared-boxed-in-trait.stderr b/src/test/ui/async-await/in-trait/async-example-desugared-boxed-in-trait.stderr
new file mode 100644
index 000000000000..22d2928f2f56
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/async-example-desugared-boxed-in-trait.stderr
@@ -0,0 +1,17 @@
+error[E0053]: method `foo` has an incompatible type for trait
+  --> $DIR/async-example-desugared-boxed-in-trait.rs:15:28
+   |
+LL |     async fn foo(&self) -> i32 {
+   |                            ^^^ expected struct `Pin`, found opaque type
+   |
+note: type in trait
+  --> $DIR/async-example-desugared-boxed-in-trait.rs:11:22
+   |
+LL |     fn foo(&self) -> Pin<Box<dyn Future<Output = i32> + '_>>;
+   |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   = note: expected fn pointer `fn(&i32) -> Pin<Box<dyn Future<Output = i32>>>`
+              found fn pointer `fn(&i32) -> impl Future<Output = i32>`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0053`.
diff --git a/src/test/ui/async-await/in-trait/async-example-desugared-boxed.rs b/src/test/ui/async-await/in-trait/async-example-desugared-boxed.rs
new file mode 100644
index 000000000000..61d7e2520eab
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/async-example-desugared-boxed.rs
@@ -0,0 +1,24 @@
+// check-pass
+// edition: 2021
+
+#![feature(async_fn_in_trait)]
+#![feature(return_position_impl_trait_in_trait)]
+#![allow(incomplete_features)]
+
+use std::future::Future;
+use std::pin::Pin;
+
+trait MyTrait {
+    async fn foo(&self) -> i32;
+}
+
+impl MyTrait for i32 {
+    // This will break once a PR that implements #102745 is merged
+    fn foo(&self) -> Pin<Box<dyn Future<Output = i32> + '_>> {
+        Box::pin(async {
+            *self
+        })
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/async-await/in-trait/async-example-desugared-in-trait.rs b/src/test/ui/async-await/in-trait/async-example-desugared-in-trait.rs
new file mode 100644
index 000000000000..feeda719e030
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/async-example-desugared-in-trait.rs
@@ -0,0 +1,21 @@
+// check-pass
+// edition: 2021
+
+#![feature(async_fn_in_trait)]
+#![feature(return_position_impl_trait_in_trait)]
+#![allow(incomplete_features)]
+
+use std::future::Future;
+
+trait MyTrait {
+    fn foo(&self) -> impl Future<Output = i32> + '_;
+}
+
+impl MyTrait for i32 {
+    // This will break once a PR that implements #102745 is merged
+    async fn foo(&self) -> i32 {
+        *self
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/async-await/in-trait/async-example-desugared.rs b/src/test/ui/async-await/in-trait/async-example-desugared.rs
new file mode 100644
index 000000000000..1313c9edd861
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/async-example-desugared.rs
@@ -0,0 +1,23 @@
+// check-pass
+// edition: 2021
+
+#![feature(async_fn_in_trait)]
+#![feature(return_position_impl_trait_in_trait)]
+#![allow(incomplete_features)]
+
+use std::future::Future;
+
+trait MyTrait {
+    async fn foo(&self) -> i32;
+}
+
+impl MyTrait for i32 {
+    // This will break once a PR that implements #102745 is merged
+    fn foo(&self) -> impl Future<Output = i32> + '_ {
+        async {
+            *self
+        }
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/async-await/in-trait/async-example.rs b/src/test/ui/async-await/in-trait/async-example.rs
new file mode 100644
index 000000000000..abf94ef7450f
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/async-example.rs
@@ -0,0 +1,32 @@
+// check-pass
+// edition: 2021
+
+#![feature(async_fn_in_trait)]
+#![allow(incomplete_features)]
+
+trait MyTrait {
+    async fn foo(&self) -> i32;
+    async fn bar(&self) -> i32;
+}
+
+impl MyTrait for i32 {
+    async fn foo(&self) -> i32 {
+        *self
+    }
+
+    async fn bar(&self) -> i32 {
+        self.foo().await
+    }
+}
+
+fn main() {
+    let x = 5;
+    // Calling from non-async context
+    let _ = x.foo();
+    let _ = x.bar();
+    // Calling from async block in non-async context
+    async {
+        let _: i32 = x.foo().await;
+        let _: i32 = x.bar().await;
+    };
+}
diff --git a/src/test/ui/async-await/in-trait/async-generics-and-bounds.rs b/src/test/ui/async-await/in-trait/async-generics-and-bounds.rs
new file mode 100644
index 000000000000..a73d55adfece
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/async-generics-and-bounds.rs
@@ -0,0 +1,21 @@
+// check-fail
+// known-bug: #102682
+// edition: 2021
+
+#![feature(async_fn_in_trait)]
+#![allow(incomplete_features)]
+
+use std::fmt::Debug;
+use std::hash::Hash;
+
+trait MyTrait<T, U> {
+    async fn foo(&self) -> &(T, U) where T: Debug + Sized, U: Hash;
+}
+
+impl<T, U> MyTrait<T, U> for (T, U) {
+    async fn foo(&self) -> &(T, U) {
+        self
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/async-await/in-trait/async-generics-and-bounds.stderr b/src/test/ui/async-await/in-trait/async-generics-and-bounds.stderr
new file mode 100644
index 000000000000..5c8d64fc6cb4
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/async-generics-and-bounds.stderr
@@ -0,0 +1,37 @@
+error[E0311]: the parameter type `U` may not live long enough
+  --> $DIR/async-generics-and-bounds.rs:12:28
+   |
+LL |     async fn foo(&self) -> &(T, U) where T: Debug + Sized, U: Hash;
+   |                            ^^^^^^^
+   |
+note: the parameter type `U` must be valid for the anonymous lifetime as defined here...
+  --> $DIR/async-generics-and-bounds.rs:12:18
+   |
+LL |     async fn foo(&self) -> &(T, U) where T: Debug + Sized, U: Hash;
+   |                  ^
+note: ...so that the reference type `&(T, U)` does not outlive the data it points at
+  --> $DIR/async-generics-and-bounds.rs:12:28
+   |
+LL |     async fn foo(&self) -> &(T, U) where T: Debug + Sized, U: Hash;
+   |                            ^^^^^^^
+
+error[E0311]: the parameter type `T` may not live long enough
+  --> $DIR/async-generics-and-bounds.rs:12:28
+   |
+LL |     async fn foo(&self) -> &(T, U) where T: Debug + Sized, U: Hash;
+   |                            ^^^^^^^
+   |
+note: the parameter type `T` must be valid for the anonymous lifetime as defined here...
+  --> $DIR/async-generics-and-bounds.rs:12:18
+   |
+LL |     async fn foo(&self) -> &(T, U) where T: Debug + Sized, U: Hash;
+   |                  ^
+note: ...so that the reference type `&(T, U)` does not outlive the data it points at
+  --> $DIR/async-generics-and-bounds.rs:12:28
+   |
+LL |     async fn foo(&self) -> &(T, U) where T: Debug + Sized, U: Hash;
+   |                            ^^^^^^^
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0311`.
diff --git a/src/test/ui/async-await/in-trait/async-generics.rs b/src/test/ui/async-await/in-trait/async-generics.rs
new file mode 100644
index 000000000000..67000e5770ee
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/async-generics.rs
@@ -0,0 +1,18 @@
+// check-fail
+// known-bug: #102682
+// edition: 2021
+
+#![feature(async_fn_in_trait)]
+#![allow(incomplete_features)]
+
+trait MyTrait<T, U> {
+    async fn foo(&self) -> &(T, U);
+}
+
+impl<T, U> MyTrait<T, U> for (T, U) {
+    async fn foo(&self) -> &(T, U) {
+        self
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/async-await/in-trait/async-generics.stderr b/src/test/ui/async-await/in-trait/async-generics.stderr
new file mode 100644
index 000000000000..6ae73d9e3a60
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/async-generics.stderr
@@ -0,0 +1,37 @@
+error[E0311]: the parameter type `U` may not live long enough
+  --> $DIR/async-generics.rs:9:28
+   |
+LL |     async fn foo(&self) -> &(T, U);
+   |                            ^^^^^^^
+   |
+note: the parameter type `U` must be valid for the anonymous lifetime as defined here...
+  --> $DIR/async-generics.rs:9:18
+   |
+LL |     async fn foo(&self) -> &(T, U);
+   |                  ^
+note: ...so that the reference type `&(T, U)` does not outlive the data it points at
+  --> $DIR/async-generics.rs:9:28
+   |
+LL |     async fn foo(&self) -> &(T, U);
+   |                            ^^^^^^^
+
+error[E0311]: the parameter type `T` may not live long enough
+  --> $DIR/async-generics.rs:9:28
+   |
+LL |     async fn foo(&self) -> &(T, U);
+   |                            ^^^^^^^
+   |
+note: the parameter type `T` must be valid for the anonymous lifetime as defined here...
+  --> $DIR/async-generics.rs:9:18
+   |
+LL |     async fn foo(&self) -> &(T, U);
+   |                  ^
+note: ...so that the reference type `&(T, U)` does not outlive the data it points at
+  --> $DIR/async-generics.rs:9:28
+   |
+LL |     async fn foo(&self) -> &(T, U);
+   |                            ^^^^^^^
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0311`.
diff --git a/src/test/ui/async-await/in-trait/async-lifetimes-and-bounds.rs b/src/test/ui/async-await/in-trait/async-lifetimes-and-bounds.rs
new file mode 100644
index 000000000000..3f7448cecd15
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/async-lifetimes-and-bounds.rs
@@ -0,0 +1,20 @@
+// check-fail
+// known-bug: #102682
+// edition: 2021
+
+#![feature(async_fn_in_trait)]
+#![allow(incomplete_features)]
+
+use std::fmt::Debug;
+
+trait MyTrait<'a, 'b, T> {
+    async fn foo(&'a self, key: &'b T) -> (&'a Self, &'b T) where T: Debug + Sized;
+}
+
+impl<'a, 'b, T, U> MyTrait<'a, 'b, T> for U {
+    async fn foo(&'a self, key: &'b T) -> (&'a U, &'b T) {
+        (self, key)
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/async-await/in-trait/async-lifetimes-and-bounds.stderr b/src/test/ui/async-await/in-trait/async-lifetimes-and-bounds.stderr
new file mode 100644
index 000000000000..0f0242027433
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/async-lifetimes-and-bounds.stderr
@@ -0,0 +1,23 @@
+error[E0309]: the parameter type `Self` may not live long enough
+  --> $DIR/async-lifetimes-and-bounds.rs:11:43
+   |
+LL |     async fn foo(&'a self, key: &'b T) -> (&'a Self, &'b T) where T: Debug + Sized;
+   |                                           ^^^^^^^^^^^^^^^^^
+   |
+   = help: consider adding an explicit lifetime bound `Self: 'a`...
+   = note: ...so that the reference type `&'a Self` does not outlive the data it points at
+
+error[E0309]: the parameter type `T` may not live long enough
+  --> $DIR/async-lifetimes-and-bounds.rs:11:43
+   |
+LL |     async fn foo(&'a self, key: &'b T) -> (&'a Self, &'b T) where T: Debug + Sized;
+   |                                           ^^^^^^^^^^^^^^^^^ ...so that the reference type `&'b T` does not outlive the data it points at
+   |
+help: consider adding an explicit lifetime bound...
+   |
+LL | trait MyTrait<'a, 'b, T: 'b> {
+   |                        ++++
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0309`.
diff --git a/src/test/ui/async-await/in-trait/async-lifetimes.rs b/src/test/ui/async-await/in-trait/async-lifetimes.rs
new file mode 100644
index 000000000000..acbac471cf7e
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/async-lifetimes.rs
@@ -0,0 +1,18 @@
+// check-fail
+// known-bug: #102682
+// edition: 2021
+
+#![feature(async_fn_in_trait)]
+#![allow(incomplete_features)]
+
+trait MyTrait<'a, 'b, T> {
+    async fn foo(&'a self, key: &'b T) -> (&'a Self, &'b T);
+}
+
+impl<'a, 'b, T, U> MyTrait<'a, 'b, T> for U {
+    async fn foo(&'a self, key: &'b T) -> (&'a U, &'b T) {
+        (self, key)
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/async-await/in-trait/async-lifetimes.stderr b/src/test/ui/async-await/in-trait/async-lifetimes.stderr
new file mode 100644
index 000000000000..9a7d294bb176
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/async-lifetimes.stderr
@@ -0,0 +1,23 @@
+error[E0309]: the parameter type `Self` may not live long enough
+  --> $DIR/async-lifetimes.rs:9:43
+   |
+LL |     async fn foo(&'a self, key: &'b T) -> (&'a Self, &'b T);
+   |                                           ^^^^^^^^^^^^^^^^^
+   |
+   = help: consider adding an explicit lifetime bound `Self: 'a`...
+   = note: ...so that the reference type `&'a Self` does not outlive the data it points at
+
+error[E0309]: the parameter type `T` may not live long enough
+  --> $DIR/async-lifetimes.rs:9:43
+   |
+LL |     async fn foo(&'a self, key: &'b T) -> (&'a Self, &'b T);
+   |                                           ^^^^^^^^^^^^^^^^^ ...so that the reference type `&'b T` does not outlive the data it points at
+   |
+help: consider adding an explicit lifetime bound...
+   |
+LL | trait MyTrait<'a, 'b, T: 'b> {
+   |                        ++++
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0309`.
diff --git a/src/test/ui/async-await/in-trait/async-recursive-generic.rs b/src/test/ui/async-await/in-trait/async-recursive-generic.rs
new file mode 100644
index 000000000000..6839abd381c3
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/async-recursive-generic.rs
@@ -0,0 +1,21 @@
+// edition: 2021
+
+#![feature(async_fn_in_trait)]
+#![allow(incomplete_features)]
+
+trait MyTrait<T> {
+    async fn foo_recursive(&self, n: usize) -> T;
+}
+
+impl<T> MyTrait<T> for T where T: Copy {
+    async fn foo_recursive(&self, n: usize) -> T {
+        //~^ ERROR recursion in an `async fn` requires boxing
+        if n > 0 {
+            self.foo_recursive(n - 1).await
+        } else {
+            *self
+        }
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/async-await/in-trait/async-recursive-generic.stderr b/src/test/ui/async-await/in-trait/async-recursive-generic.stderr
new file mode 100644
index 000000000000..cab173bdd5b7
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/async-recursive-generic.stderr
@@ -0,0 +1,12 @@
+error[E0733]: recursion in an `async fn` requires boxing
+  --> $DIR/async-recursive-generic.rs:11:48
+   |
+LL |     async fn foo_recursive(&self, n: usize) -> T {
+   |                                                ^ recursive `async fn`
+   |
+   = note: a recursive `async fn` must be rewritten to return a boxed `dyn Future`
+   = note: consider using the `async_recursion` crate: https://crates.io/crates/async_recursion
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0733`.
diff --git a/src/test/ui/async-await/in-trait/async-recursive.rs b/src/test/ui/async-await/in-trait/async-recursive.rs
new file mode 100644
index 000000000000..61119f8095bc
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/async-recursive.rs
@@ -0,0 +1,21 @@
+// edition: 2021
+
+#![feature(async_fn_in_trait)]
+#![allow(incomplete_features)]
+
+trait MyTrait {
+    async fn foo_recursive(&self, n: usize) -> i32;
+}
+
+impl MyTrait for i32 {
+    async fn foo_recursive(&self, n: usize) -> i32 {
+        //~^ ERROR recursion in an `async fn` requires boxing
+        if n > 0 {
+            self.foo_recursive(n - 1).await
+        } else {
+            *self
+        }
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/async-await/in-trait/async-recursive.stderr b/src/test/ui/async-await/in-trait/async-recursive.stderr
new file mode 100644
index 000000000000..9feff37b3fe4
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/async-recursive.stderr
@@ -0,0 +1,12 @@
+error[E0733]: recursion in an `async fn` requires boxing
+  --> $DIR/async-recursive.rs:11:48
+   |
+LL |     async fn foo_recursive(&self, n: usize) -> i32 {
+   |                                                ^^^ recursive `async fn`
+   |
+   = note: a recursive `async fn` must be rewritten to return a boxed `dyn Future`
+   = note: consider using the `async_recursion` crate: https://crates.io/crates/async_recursion
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0733`.
diff --git a/src/test/ui/async-await/in-trait/fn-not-async-err.rs b/src/test/ui/async-await/in-trait/fn-not-async-err.rs
new file mode 100644
index 000000000000..f94d32145a29
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/fn-not-async-err.rs
@@ -0,0 +1,17 @@
+// edition: 2021
+
+#![feature(async_fn_in_trait)]
+#![allow(incomplete_features)]
+
+trait MyTrait {
+    async fn foo(&self) -> i32;
+}
+
+impl MyTrait for i32 {
+    fn foo(&self) -> i32 {
+        //~^ ERROR: `i32` is not a future [E0277]
+        *self
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/async-await/in-trait/fn-not-async-err.stderr b/src/test/ui/async-await/in-trait/fn-not-async-err.stderr
new file mode 100644
index 000000000000..03321dc5b5af
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/fn-not-async-err.stderr
@@ -0,0 +1,17 @@
+error[E0277]: `i32` is not a future
+  --> $DIR/fn-not-async-err.rs:11:22
+   |
+LL |     fn foo(&self) -> i32 {
+   |                      ^^^ `i32` is not a future
+   |
+   = help: the trait `Future` is not implemented for `i32`
+   = note: i32 must be a future or must implement `IntoFuture` to be awaited
+note: required by a bound in `MyTrait::foo::{opaque#0}`
+  --> $DIR/fn-not-async-err.rs:7:28
+   |
+LL |     async fn foo(&self) -> i32;
+   |                            ^^^ required by this bound in `MyTrait::foo::{opaque#0}`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0277`.
diff --git a/src/test/ui/async-await/in-trait/fn-not-async-err2.rs b/src/test/ui/async-await/in-trait/fn-not-async-err2.rs
new file mode 100644
index 000000000000..594baa91ad8b
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/fn-not-async-err2.rs
@@ -0,0 +1,21 @@
+// edition: 2021
+
+#![feature(async_fn_in_trait)]
+#![allow(incomplete_features)]
+
+use std::future::Future;
+
+trait MyTrait {
+    async fn foo(&self) -> i32;
+}
+
+impl MyTrait for i32 {
+    fn foo(&self) -> impl Future<Output = i32> {
+        //~^ ERROR `impl Trait` only allowed in function and inherent method return types, not in `impl` method return [E0562]
+        async {
+            *self
+        }
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/async-await/in-trait/fn-not-async-err2.stderr b/src/test/ui/async-await/in-trait/fn-not-async-err2.stderr
new file mode 100644
index 000000000000..f591f1847729
--- /dev/null
+++ b/src/test/ui/async-await/in-trait/fn-not-async-err2.stderr
@@ -0,0 +1,12 @@
+error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `impl` method return
+  --> $DIR/fn-not-async-err2.rs:13:22
+   |
+LL |     fn foo(&self) -> impl Future<Output = i32> {
+   |                      ^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #91611 <https://github.com/rust-lang/rust/issues/91611> for more information
+   = help: add `#![feature(return_position_impl_trait_in_trait)]` to the crate attributes to enable
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0562`.
diff --git a/src/test/ui/async-await/issue-98634.rs b/src/test/ui/async-await/issue-98634.rs
new file mode 100644
index 000000000000..b0d38687f01c
--- /dev/null
+++ b/src/test/ui/async-await/issue-98634.rs
@@ -0,0 +1,50 @@
+// edition: 2021
+
+use std::{
+    future::Future,
+    pin::Pin,
+    task::{Context, Poll, Waker},
+};
+
+pub struct StructAsync<F: Fn() -> Pin<Box<dyn Future<Output = ()>>>> {
+    pub callback: F,
+}
+
+impl<F> Future for StructAsync<F>
+where
+    F: Fn() -> Pin<Box<dyn Future<Output = ()>>>,
+{
+    type Output = ();
+
+    fn poll(self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<Self::Output> {
+        Poll::Pending
+    }
+}
+
+async fn callback() {}
+
+struct Runtime;
+
+fn waker() -> &'static Waker {
+    todo!()
+}
+
+impl Runtime {
+    #[track_caller]
+    pub fn block_on<F: Future>(&self, mut future: F) -> F::Output {
+        loop {
+            unsafe {
+                Pin::new_unchecked(&mut future).poll(&mut Context::from_waker(waker()));
+            }
+        }
+    }
+}
+
+fn main() {
+    Runtime.block_on(async {
+        StructAsync { callback }.await;
+        //~^ ERROR expected `fn() -> impl Future<Output = ()> {callback}` to be a fn item that returns `Pin<Box<(dyn Future<Output = ()> + 'static)>>`, but it returns `impl Future<Output = ()>`
+        //~| ERROR expected `fn() -> impl Future<Output = ()> {callback}` to be a fn item that returns `Pin<Box<(dyn Future<Output = ()> + 'static)>>`, but it returns `impl Future<Output = ()>`
+        //~| ERROR expected `fn() -> impl Future<Output = ()> {callback}` to be a fn item that returns `Pin<Box<(dyn Future<Output = ()> + 'static)>>`, but it returns `impl Future<Output = ()>`
+    });
+}
diff --git a/src/test/ui/async-await/issue-98634.stderr b/src/test/ui/async-await/issue-98634.stderr
new file mode 100644
index 000000000000..5160e48d88af
--- /dev/null
+++ b/src/test/ui/async-await/issue-98634.stderr
@@ -0,0 +1,60 @@
+error[E0271]: expected `fn() -> impl Future<Output = ()> {callback}` to be a fn item that returns `Pin<Box<(dyn Future<Output = ()> + 'static)>>`, but it returns `impl Future<Output = ()>`
+  --> $DIR/issue-98634.rs:45:23
+   |
+LL |         StructAsync { callback }.await;
+   |                       ^^^^^^^^ expected struct `Pin`, found opaque type
+   |
+note: while checking the return type of the `async fn`
+  --> $DIR/issue-98634.rs:24:21
+   |
+LL | async fn callback() {}
+   |                     ^ checked the `Output` of this `async fn`, found opaque type
+   = note:   expected struct `Pin<Box<(dyn Future<Output = ()> + 'static)>>`
+           found opaque type `impl Future<Output = ()>`
+note: required by a bound in `StructAsync`
+  --> $DIR/issue-98634.rs:9:35
+   |
+LL | pub struct StructAsync<F: Fn() -> Pin<Box<dyn Future<Output = ()>>>> {
+   |                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `StructAsync`
+
+error[E0271]: expected `fn() -> impl Future<Output = ()> {callback}` to be a fn item that returns `Pin<Box<(dyn Future<Output = ()> + 'static)>>`, but it returns `impl Future<Output = ()>`
+  --> $DIR/issue-98634.rs:45:9
+   |
+LL |         StructAsync { callback }.await;
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^ expected struct `Pin`, found opaque type
+   |
+note: while checking the return type of the `async fn`
+  --> $DIR/issue-98634.rs:24:21
+   |
+LL | async fn callback() {}
+   |                     ^ checked the `Output` of this `async fn`, found opaque type
+   = note:   expected struct `Pin<Box<(dyn Future<Output = ()> + 'static)>>`
+           found opaque type `impl Future<Output = ()>`
+note: required by a bound in `StructAsync`
+  --> $DIR/issue-98634.rs:9:35
+   |
+LL | pub struct StructAsync<F: Fn() -> Pin<Box<dyn Future<Output = ()>>>> {
+   |                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `StructAsync`
+
+error[E0271]: expected `fn() -> impl Future<Output = ()> {callback}` to be a fn item that returns `Pin<Box<(dyn Future<Output = ()> + 'static)>>`, but it returns `impl Future<Output = ()>`
+  --> $DIR/issue-98634.rs:45:33
+   |
+LL |         StructAsync { callback }.await;
+   |                                 ^^^^^^ expected struct `Pin`, found opaque type
+   |
+note: while checking the return type of the `async fn`
+  --> $DIR/issue-98634.rs:24:21
+   |
+LL | async fn callback() {}
+   |                     ^ checked the `Output` of this `async fn`, found opaque type
+   = note:   expected struct `Pin<Box<(dyn Future<Output = ()> + 'static)>>`
+           found opaque type `impl Future<Output = ()>`
+note: required by a bound in `StructAsync`
+  --> $DIR/issue-98634.rs:9:35
+   |
+LL | pub struct StructAsync<F: Fn() -> Pin<Box<dyn Future<Output = ()>>>> {
+   |                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `StructAsync`
+
+error: aborting due to 3 previous errors
+
+For more information about this error, try `rustc --explain E0271`.
diff --git a/src/test/ui/async-await/issues/issue-65159.rs b/src/test/ui/async-await/issues/issue-65159.rs
index 1dbf5db6c32e..df2ca025705d 100644
--- a/src/test/ui/async-await/issues/issue-65159.rs
+++ b/src/test/ui/async-await/issues/issue-65159.rs
@@ -6,7 +6,6 @@ async fn copy() -> Result<()>
 //~^ ERROR this enum takes 2 generic arguments
 {
     Ok(())
-    //~^ ERROR type annotations needed
 }
 
 fn main() { }
diff --git a/src/test/ui/async-await/issues/issue-65159.stderr b/src/test/ui/async-await/issues/issue-65159.stderr
index 9918f569cbc8..45f5ec40cd75 100644
--- a/src/test/ui/async-await/issues/issue-65159.stderr
+++ b/src/test/ui/async-await/issues/issue-65159.stderr
@@ -16,18 +16,6 @@ help: add missing generic argument
 LL | async fn copy() -> Result<(), E>
    |                             +++
 
-error[E0282]: type annotations needed
-  --> $DIR/issue-65159.rs:8:5
-   |
-LL |     Ok(())
-   |     ^^ cannot infer type of the type parameter `E` declared on the enum `Result`
-   |
-help: consider specifying the generic arguments
-   |
-LL |     Ok::<(), E>(())
-   |       +++++++++
+error: aborting due to previous error
 
-error: aborting due to 2 previous errors
-
-Some errors have detailed explanations: E0107, E0282.
-For more information about an error, try `rustc --explain E0107`.
+For more information about this error, try `rustc --explain E0107`.
diff --git a/src/test/ui/async-await/issues/issue-72312.stderr b/src/test/ui/async-await/issues/issue-72312.stderr
index 5e5a980adb9f..aa947b690036 100644
--- a/src/test/ui/async-await/issues/issue-72312.stderr
+++ b/src/test/ui/async-await/issues/issue-72312.stderr
@@ -1,5 +1,5 @@
 error[E0521]: borrowed data escapes outside of associated function
-  --> $DIR/issue-72312.rs:12:24
+  --> $DIR/issue-72312.rs:12:9
    |
 LL |       pub async fn start(&self) {
    |                          -----
@@ -7,17 +7,16 @@ LL |       pub async fn start(&self) {
    |                          `self` is a reference that is only valid in the associated function body
    |                          let's call the lifetime of this reference `'1`
 ...
-LL |           require_static(async move {
-   |  ________________________^
+LL | /         require_static(async move {
 LL | |
 LL | |
 LL | |
 LL | |             &self;
 LL | |         });
-   | |         ^
-   | |         |
-   | |_________`self` escapes the associated function body here
-   |           argument requires that `'1` must outlive `'static`
+   | |          ^
+   | |          |
+   | |__________`self` escapes the associated function body here
+   |            argument requires that `'1` must outlive `'static`
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/async-await/multiple-lifetimes/ret-impl-trait-one.stderr b/src/test/ui/async-await/multiple-lifetimes/ret-impl-trait-one.stderr
index 3128b4df4e2d..ae4d0d5853ca 100644
--- a/src/test/ui/async-await/multiple-lifetimes/ret-impl-trait-one.stderr
+++ b/src/test/ui/async-await/multiple-lifetimes/ret-impl-trait-one.stderr
@@ -25,7 +25,7 @@ LL | |     (a, b)
 LL | | }
    | |_^
    |
-help: to declare that the `impl Trait` captures `'b`, you can add an explicit `'b` lifetime bound
+help: to declare that `impl Trait<'a>` captures `'b`, you can add an explicit `'b` lifetime bound
    |
 LL | async fn async_ret_impl_trait1<'a, 'b>(a: &'a u8, b: &'b u8) -> impl Trait<'a> + 'b {
    |                                                                                ++++
diff --git a/src/test/ui/attributes/key-value-non-ascii.rs b/src/test/ui/attributes/key-value-non-ascii.rs
index 12942eabdf7b..e14e2fc05ad3 100644
--- a/src/test/ui/attributes/key-value-non-ascii.rs
+++ b/src/test/ui/attributes/key-value-non-ascii.rs
@@ -1,4 +1,4 @@
 #![feature(rustc_attrs)]
 
-#[rustc_dummy = b"ffi.rs"] //~ ERROR non-ASCII character in byte constant
+#[rustc_dummy = b"ffi.rs"] //~ ERROR non-ASCII character in byte string literal
 fn main() {}
diff --git a/src/test/ui/attributes/key-value-non-ascii.stderr b/src/test/ui/attributes/key-value-non-ascii.stderr
index 422107867f7f..23d482de6a86 100644
--- a/src/test/ui/attributes/key-value-non-ascii.stderr
+++ b/src/test/ui/attributes/key-value-non-ascii.stderr
@@ -1,8 +1,8 @@
-error: non-ASCII character in byte constant
+error: non-ASCII character in byte string literal
   --> $DIR/key-value-non-ascii.rs:3:19
    |
 LL | #[rustc_dummy = b"ffi.rs"]
-   |                   ^ byte constant must be ASCII
+   |                   ^ must be ASCII
    |
 help: if you meant to use the UTF-8 encoding of 'ffi', use \xHH escapes
    |
diff --git a/src/test/ui/borrowck/anonymous-region-in-apit.rs b/src/test/ui/borrowck/anonymous-region-in-apit.rs
new file mode 100644
index 000000000000..7799a7cb151d
--- /dev/null
+++ b/src/test/ui/borrowck/anonymous-region-in-apit.rs
@@ -0,0 +1,12 @@
+#![feature(anonymous_lifetime_in_impl_trait)]
+
+trait Foo<T> {
+    fn bar(self, baz: T);
+}
+
+fn qux(foo: impl Foo<&str>) {
+    |baz: &str| foo.bar(baz);
+    //~^ ERROR borrowed data escapes outside of closure
+}
+
+fn main() {}
diff --git a/src/test/ui/borrowck/anonymous-region-in-apit.stderr b/src/test/ui/borrowck/anonymous-region-in-apit.stderr
new file mode 100644
index 000000000000..9e100f8ac3c5
--- /dev/null
+++ b/src/test/ui/borrowck/anonymous-region-in-apit.stderr
@@ -0,0 +1,16 @@
+error[E0521]: borrowed data escapes outside of closure
+  --> $DIR/anonymous-region-in-apit.rs:8:17
+   |
+LL | fn qux(foo: impl Foo<&str>) {
+   |        --- lifetime `'2` appears in the type of `foo`
+LL |     |baz: &str| foo.bar(baz);
+   |      ---  -     ^^^^^^^^^^^^
+   |      |    |     |
+   |      |    |     `baz` escapes the closure body here
+   |      |    |     argument requires that `'1` must outlive `'2`
+   |      |    let's call the lifetime of this reference `'1`
+   |      `baz` is a reference that is only valid in the closure body
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0521`.
diff --git a/src/test/ui/borrowck/async-reference-generality.rs b/src/test/ui/borrowck/async-reference-generality.rs
new file mode 100644
index 000000000000..487d1ac81bfc
--- /dev/null
+++ b/src/test/ui/borrowck/async-reference-generality.rs
@@ -0,0 +1,35 @@
+// check-fail
+// known-bug: #99492
+// edition: 2021
+
+use std::marker::PhantomData;
+
+pub struct Struct<I, T>(PhantomData<fn() -> <Self as It>::Item>)
+where
+    Self: It;
+
+impl<I> It for Struct<I, I::Item>
+where
+    I: It,
+{
+    type Item = ();
+}
+
+pub trait It {
+    type Item;
+}
+
+fn f() -> impl Send {
+    async {
+        let _x = Struct::<Empty<&'static ()>, _>(PhantomData);
+        async {}.await;
+    }
+}
+
+pub struct Empty<T>(PhantomData<fn() -> T>);
+
+impl<T> It for Empty<T> {
+    type Item = T;
+}
+
+fn main() {}
diff --git a/src/test/ui/borrowck/async-reference-generality.stderr b/src/test/ui/borrowck/async-reference-generality.stderr
new file mode 100644
index 000000000000..af720ad29314
--- /dev/null
+++ b/src/test/ui/borrowck/async-reference-generality.stderr
@@ -0,0 +1,27 @@
+error[E0308]: mismatched types
+  --> $DIR/async-reference-generality.rs:23:5
+   |
+LL | /     async {
+LL | |         let _x = Struct::<Empty<&'static ()>, _>(PhantomData);
+LL | |         async {}.await;
+LL | |     }
+   | |_____^ one type is more general than the other
+   |
+   = note: expected reference `&()`
+              found reference `&()`
+
+error[E0308]: mismatched types
+  --> $DIR/async-reference-generality.rs:23:5
+   |
+LL | /     async {
+LL | |         let _x = Struct::<Empty<&'static ()>, _>(PhantomData);
+LL | |         async {}.await;
+LL | |     }
+   | |_____^ one type is more general than the other
+   |
+   = note: expected reference `&()`
+              found reference `&()`
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/ui/borrowck/borrow-immutable-upvar-mutation.rs b/src/test/ui/borrowck/borrow-immutable-upvar-mutation.rs
index e2f016614bf8..a3350024e756 100644
--- a/src/test/ui/borrowck/borrow-immutable-upvar-mutation.rs
+++ b/src/test/ui/borrowck/borrow-immutable-upvar-mutation.rs
@@ -1,4 +1,4 @@
-#![feature(unboxed_closures)]
+#![feature(unboxed_closures, tuple_trait)]
 
 // Tests that we can't assign to or mutably borrow upvars from `Fn`
 // closures (issue #17780)
@@ -7,10 +7,10 @@ fn set(x: &mut usize) {
     *x = 5;
 }
 
-fn to_fn<A, F: Fn<A>>(f: F) -> F {
+fn to_fn<A: std::marker::Tuple, F: Fn<A>>(f: F) -> F {
     f
 }
-fn to_fn_mut<A, F: FnMut<A>>(f: F) -> F {
+fn to_fn_mut<A: std::marker::Tuple, F: FnMut<A>>(f: F) -> F {
     f
 }
 
diff --git a/src/test/ui/borrowck/borrow-immutable-upvar-mutation.stderr b/src/test/ui/borrowck/borrow-immutable-upvar-mutation.stderr
index 093589ed0921..a0eaf1f163b0 100644
--- a/src/test/ui/borrowck/borrow-immutable-upvar-mutation.stderr
+++ b/src/test/ui/borrowck/borrow-immutable-upvar-mutation.stderr
@@ -1,8 +1,8 @@
 error[E0594]: cannot assign to `x`, as it is a captured variable in a `Fn` closure
   --> $DIR/borrow-immutable-upvar-mutation.rs:21:27
    |
-LL | fn to_fn<A, F: Fn<A>>(f: F) -> F {
-   |                          - change this to accept `FnMut` instead of `Fn`
+LL | fn to_fn<A: std::marker::Tuple, F: Fn<A>>(f: F) -> F {
+   |                                              - change this to accept `FnMut` instead of `Fn`
 ...
 LL |         let _f = to_fn(|| x = 42);
    |                  ----- -- ^^^^^^ cannot assign
@@ -13,8 +13,8 @@ LL |         let _f = to_fn(|| x = 42);
 error[E0596]: cannot borrow `y` as mutable, as it is a captured variable in a `Fn` closure
   --> $DIR/borrow-immutable-upvar-mutation.rs:24:31
    |
-LL | fn to_fn<A, F: Fn<A>>(f: F) -> F {
-   |                          - change this to accept `FnMut` instead of `Fn`
+LL | fn to_fn<A: std::marker::Tuple, F: Fn<A>>(f: F) -> F {
+   |                                              - change this to accept `FnMut` instead of `Fn`
 ...
 LL |         let _g = to_fn(|| set(&mut y));
    |                  ----- --     ^^^^^^ cannot borrow as mutable
@@ -25,8 +25,8 @@ LL |         let _g = to_fn(|| set(&mut y));
 error[E0594]: cannot assign to `z`, as it is a captured variable in a `Fn` closure
   --> $DIR/borrow-immutable-upvar-mutation.rs:29:22
    |
-LL | fn to_fn<A, F: Fn<A>>(f: F) -> F {
-   |                          - change this to accept `FnMut` instead of `Fn`
+LL | fn to_fn<A: std::marker::Tuple, F: Fn<A>>(f: F) -> F {
+   |                                              - change this to accept `FnMut` instead of `Fn`
 ...
 LL |             to_fn(|| z = 42);
    |             ----- -- ^^^^^^ cannot assign
@@ -37,8 +37,8 @@ LL |             to_fn(|| z = 42);
 error[E0594]: cannot assign to `x`, as it is a captured variable in a `Fn` closure
   --> $DIR/borrow-immutable-upvar-mutation.rs:36:32
    |
-LL | fn to_fn<A, F: Fn<A>>(f: F) -> F {
-   |                          - change this to accept `FnMut` instead of `Fn`
+LL | fn to_fn<A: std::marker::Tuple, F: Fn<A>>(f: F) -> F {
+   |                                              - change this to accept `FnMut` instead of `Fn`
 ...
 LL |         let _f = to_fn(move || x = 42);
    |                  ----- ------- ^^^^^^ cannot assign
@@ -49,8 +49,8 @@ LL |         let _f = to_fn(move || x = 42);
 error[E0596]: cannot borrow `y` as mutable, as it is a captured variable in a `Fn` closure
   --> $DIR/borrow-immutable-upvar-mutation.rs:39:36
    |
-LL | fn to_fn<A, F: Fn<A>>(f: F) -> F {
-   |                          - change this to accept `FnMut` instead of `Fn`
+LL | fn to_fn<A: std::marker::Tuple, F: Fn<A>>(f: F) -> F {
+   |                                              - change this to accept `FnMut` instead of `Fn`
 ...
 LL |         let _g = to_fn(move || set(&mut y));
    |                  ----- -------     ^^^^^^ cannot borrow as mutable
@@ -61,8 +61,8 @@ LL |         let _g = to_fn(move || set(&mut y));
 error[E0594]: cannot assign to `z`, as it is a captured variable in a `Fn` closure
   --> $DIR/borrow-immutable-upvar-mutation.rs:44:27
    |
-LL | fn to_fn<A, F: Fn<A>>(f: F) -> F {
-   |                          - change this to accept `FnMut` instead of `Fn`
+LL | fn to_fn<A: std::marker::Tuple, F: Fn<A>>(f: F) -> F {
+   |                                              - change this to accept `FnMut` instead of `Fn`
 ...
 LL |             to_fn(move || z = 42);
    |             ----- ------- ^^^^^^ cannot assign
diff --git a/src/test/ui/borrowck/borrowck-borrowed-uniq-rvalue-2.stderr b/src/test/ui/borrowck/borrowck-borrowed-uniq-rvalue-2.stderr
index a6af129bf39f..4eeec09b9104 100644
--- a/src/test/ui/borrowck/borrowck-borrowed-uniq-rvalue-2.stderr
+++ b/src/test/ui/borrowck/borrowck-borrowed-uniq-rvalue-2.stderr
@@ -4,7 +4,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     let x = defer(&vec!["Goodbye", "world!"]);
    |                    ^^^^^^^^^^^^^^^^^^^^^^^^^ - temporary value is freed at the end of this statement
    |                    |
-   |                    creates a temporary which is freed while still in use
+   |                    creates a temporary value which is freed while still in use
 LL |     x.x[0];
    |     ------ borrow later used here
    |
diff --git a/src/test/ui/borrowck/borrowck-borrowed-uniq-rvalue.stderr b/src/test/ui/borrowck/borrowck-borrowed-uniq-rvalue.stderr
index dea8ac90bec2..c62d5f903c8d 100644
--- a/src/test/ui/borrowck/borrowck-borrowed-uniq-rvalue.stderr
+++ b/src/test/ui/borrowck/borrowck-borrowed-uniq-rvalue.stderr
@@ -4,7 +4,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     buggy_map.insert(42, &*Box::new(1));
    |                            ^^^^^^^^^^^ - temporary value is freed at the end of this statement
    |                            |
-   |                            creates a temporary which is freed while still in use
+   |                            creates a temporary value which is freed while still in use
 ...
 LL |     buggy_map.insert(43, &*tmp);
    |     --------------------------- borrow later used here
diff --git a/src/test/ui/borrowck/borrowck-move-by-capture.rs b/src/test/ui/borrowck/borrowck-move-by-capture.rs
index f26edef17f34..6f0eb1870f32 100644
--- a/src/test/ui/borrowck/borrowck-move-by-capture.rs
+++ b/src/test/ui/borrowck/borrowck-move-by-capture.rs
@@ -1,7 +1,7 @@
-#![feature(unboxed_closures)]
+#![feature(unboxed_closures, tuple_trait)]
 
-fn to_fn_mut<A,F:FnMut<A>>(f: F) -> F { f }
-fn to_fn_once<A,F:FnOnce<A>>(f: F) -> F { f }
+fn to_fn_mut<A:std::marker::Tuple,F:FnMut<A>>(f: F) -> F { f }
+fn to_fn_once<A:std::marker::Tuple,F:FnOnce<A>>(f: F) -> F { f }
 
 pub fn main() {
     let bar: Box<_> = Box::new(3);
diff --git a/src/test/ui/borrowck/issue-103624.rs b/src/test/ui/borrowck/issue-103624.rs
new file mode 100644
index 000000000000..f1fa95f92469
--- /dev/null
+++ b/src/test/ui/borrowck/issue-103624.rs
@@ -0,0 +1,31 @@
+// edition:2021
+
+struct StructA {
+    b: StructB,
+}
+
+async fn spawn_blocking<T>(f: impl (Fn() -> T) + Send + Sync + 'static) -> T {
+    todo!()
+}
+
+impl StructA {
+    async fn foo(&self) {
+        let bar = self.b.bar().await;
+        spawn_blocking(move || {
+            //~^ ERROR borrowed data escapes outside of associated function
+            self.b;
+            //~^ ERROR cannot move out of `self.b`, as `self` is a captured variable in an `Fn` closure
+        })
+        .await;
+    }
+}
+
+struct StructB {}
+
+impl StructB {
+    async fn bar(&self) -> Option<u8> {
+        None
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/borrowck/issue-103624.stderr b/src/test/ui/borrowck/issue-103624.stderr
new file mode 100644
index 000000000000..e6a35dd8801a
--- /dev/null
+++ b/src/test/ui/borrowck/issue-103624.stderr
@@ -0,0 +1,35 @@
+error[E0507]: cannot move out of `self.b`, as `self` is a captured variable in an `Fn` closure
+  --> $DIR/issue-103624.rs:16:13
+   |
+LL |     async fn foo(&self) {
+   |                  ----- captured outer variable
+LL |         let bar = self.b.bar().await;
+LL |         spawn_blocking(move || {
+   |                        ------- captured by this `Fn` closure
+LL |
+LL |             self.b;
+   |             ^^^^^^ move occurs because `self.b` has type `StructB`, which does not implement the `Copy` trait
+
+error[E0521]: borrowed data escapes outside of associated function
+  --> $DIR/issue-103624.rs:14:9
+   |
+LL |       async fn foo(&self) {
+   |                    -----
+   |                    |
+   |                    `self` is a reference that is only valid in the associated function body
+   |                    let's call the lifetime of this reference `'1`
+LL |           let bar = self.b.bar().await;
+LL | /         spawn_blocking(move || {
+LL | |
+LL | |             self.b;
+LL | |
+LL | |         })
+   | |          ^
+   | |          |
+   | |__________`self` escapes the associated function body here
+   |            argument requires that `'1` must outlive `'static`
+
+error: aborting due to 2 previous errors
+
+Some errors have detailed explanations: E0507, E0521.
+For more information about an error, try `rustc --explain E0507`.
diff --git a/src/test/ui/borrowck/issue-11493.stderr b/src/test/ui/borrowck/issue-11493.stderr
index a5d1f2816f1c..2720b09b0fc5 100644
--- a/src/test/ui/borrowck/issue-11493.stderr
+++ b/src/test/ui/borrowck/issue-11493.stderr
@@ -4,7 +4,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     let y = x.as_ref().unwrap_or(&id(5));
    |                                   ^^^^^ - temporary value is freed at the end of this statement
    |                                   |
-   |                                   creates a temporary which is freed while still in use
+   |                                   creates a temporary value which is freed while still in use
 LL |     let _ = &y;
    |             -- borrow later used here
    |
diff --git a/src/test/ui/borrowck/issue-17545.stderr b/src/test/ui/borrowck/issue-17545.stderr
index 79a1e09bd7cc..3ae7e64d202b 100644
--- a/src/test/ui/borrowck/issue-17545.stderr
+++ b/src/test/ui/borrowck/issue-17545.stderr
@@ -5,7 +5,7 @@ LL |   pub fn foo<'a, F: Fn(&'a ())>(bar: F) {
    |              -- lifetime `'a` defined here
 LL | /     bar.call((
 LL | |         &id(()),
-   | |          ^^^^^^ creates a temporary which is freed while still in use
+   | |          ^^^^^^ creates a temporary value which is freed while still in use
 LL | |     ));
    | |      -- temporary value is freed at the end of this statement
    | |______|
diff --git a/src/test/ui/borrowck/issue-36082.fixed b/src/test/ui/borrowck/issue-36082.fixed
index 8640ca7a5096..8fc963a85664 100644
--- a/src/test/ui/borrowck/issue-36082.fixed
+++ b/src/test/ui/borrowck/issue-36082.fixed
@@ -10,7 +10,7 @@ fn main() {
     let val: &_ = binding.0;
     //~^ ERROR temporary value dropped while borrowed [E0716]
     //~| NOTE temporary value is freed at the end of this statement
-    //~| NOTE creates a temporary which is freed while still in use
+    //~| NOTE creates a temporary value which is freed while still in use
     //~| HELP consider using a `let` binding to create a longer lived value
     println!("{}", val);
     //~^ borrow later used here
diff --git a/src/test/ui/borrowck/issue-36082.rs b/src/test/ui/borrowck/issue-36082.rs
index 877d372fb848..20f66b4d45de 100644
--- a/src/test/ui/borrowck/issue-36082.rs
+++ b/src/test/ui/borrowck/issue-36082.rs
@@ -9,7 +9,7 @@ fn main() {
     let val: &_ = x.borrow().0;
     //~^ ERROR temporary value dropped while borrowed [E0716]
     //~| NOTE temporary value is freed at the end of this statement
-    //~| NOTE creates a temporary which is freed while still in use
+    //~| NOTE creates a temporary value which is freed while still in use
     //~| HELP consider using a `let` binding to create a longer lived value
     println!("{}", val);
     //~^ borrow later used here
diff --git a/src/test/ui/borrowck/issue-36082.stderr b/src/test/ui/borrowck/issue-36082.stderr
index 4bd586db1cdc..a6357f8182fc 100644
--- a/src/test/ui/borrowck/issue-36082.stderr
+++ b/src/test/ui/borrowck/issue-36082.stderr
@@ -4,7 +4,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     let val: &_ = x.borrow().0;
    |                   ^^^^^^^^^^  - temporary value is freed at the end of this statement
    |                   |
-   |                   creates a temporary which is freed while still in use
+   |                   creates a temporary value which is freed while still in use
 ...
 LL |     println!("{}", val);
    |                    --- borrow later used here
diff --git a/src/test/ui/borrowck/issue-82126-mismatched-subst-and-hir.rs b/src/test/ui/borrowck/issue-82126-mismatched-subst-and-hir.rs
index 2c8a700bc2ea..dd0320bc53ba 100644
--- a/src/test/ui/borrowck/issue-82126-mismatched-subst-and-hir.rs
+++ b/src/test/ui/borrowck/issue-82126-mismatched-subst-and-hir.rs
@@ -17,7 +17,6 @@ async fn buy_lock(generator: &Mutex<MarketMultiplier>) -> LockedMarket<'_> {
     //~^ ERROR this struct takes 0 lifetime arguments but 1 lifetime argument was supplied
     //~^^ ERROR this struct takes 1 generic argument but 0 generic arguments were supplied
     LockedMarket(generator.lock().unwrap().buy())
-    //~^ ERROR cannot return value referencing temporary
 }
 
 struct LockedMarket<T>(T);
diff --git a/src/test/ui/borrowck/issue-82126-mismatched-subst-and-hir.stderr b/src/test/ui/borrowck/issue-82126-mismatched-subst-and-hir.stderr
index 4bd066730439..d2b927fb664c 100644
--- a/src/test/ui/borrowck/issue-82126-mismatched-subst-and-hir.stderr
+++ b/src/test/ui/borrowck/issue-82126-mismatched-subst-and-hir.stderr
@@ -7,7 +7,7 @@ LL | async fn buy_lock(generator: &Mutex<MarketMultiplier>) -> LockedMarket<'_>
    |                                                           expected 0 lifetime arguments
    |
 note: struct defined here, with 0 lifetime parameters
-  --> $DIR/issue-82126-mismatched-subst-and-hir.rs:23:8
+  --> $DIR/issue-82126-mismatched-subst-and-hir.rs:22:8
    |
 LL | struct LockedMarket<T>(T);
    |        ^^^^^^^^^^^^
@@ -19,7 +19,7 @@ LL | async fn buy_lock(generator: &Mutex<MarketMultiplier>) -> LockedMarket<'_>
    |                                                           ^^^^^^^^^^^^ expected 1 generic argument
    |
 note: struct defined here, with 1 generic parameter: `T`
-  --> $DIR/issue-82126-mismatched-subst-and-hir.rs:23:8
+  --> $DIR/issue-82126-mismatched-subst-and-hir.rs:22:8
    |
 LL | struct LockedMarket<T>(T);
    |        ^^^^^^^^^^^^ -
@@ -28,16 +28,6 @@ help: add missing generic argument
 LL | async fn buy_lock(generator: &Mutex<MarketMultiplier>) -> LockedMarket<'_, T> {
    |                                                                          +++
 
-error[E0515]: cannot return value referencing temporary value
-  --> $DIR/issue-82126-mismatched-subst-and-hir.rs:19:5
-   |
-LL |     LockedMarket(generator.lock().unwrap().buy())
-   |     ^^^^^^^^^^^^^-------------------------^^^^^^^
-   |     |            |
-   |     |            temporary value created here
-   |     returns a value referencing data owned by the current function
+error: aborting due to 2 previous errors
 
-error: aborting due to 3 previous errors
-
-Some errors have detailed explanations: E0107, E0515.
-For more information about an error, try `rustc --explain E0107`.
+For more information about this error, try `rustc --explain E0107`.
diff --git a/src/test/ui/c-variadic/feature-gate-extended_varargs_abi_support.rs b/src/test/ui/c-variadic/feature-gate-extended_varargs_abi_support.rs
new file mode 100644
index 000000000000..087743e505d2
--- /dev/null
+++ b/src/test/ui/c-variadic/feature-gate-extended_varargs_abi_support.rs
@@ -0,0 +1,19 @@
+#![feature(abi_efiapi)]
+
+fn efiapi(f: extern "efiapi" fn(usize, ...)) {
+    //~^ ERROR: C-variadic function must have a compatible calling convention, like `C` or `cdecl`
+    //~^^ ERROR: using calling conventions other than `C` or `cdecl` for varargs functions is unstable
+    f(22, 44);
+}
+fn sysv(f: extern "sysv64" fn(usize, ...)) {
+    //~^ ERROR: C-variadic function must have a compatible calling convention, like `C` or `cdecl`
+    //~^^ ERROR: using calling conventions other than `C` or `cdecl` for varargs functions is unstable
+    f(22, 44);
+}
+fn win(f: extern "win64" fn(usize, ...)) {
+    //~^ ERROR: C-variadic function must have a compatible calling convention, like `C` or `cdecl`
+    //~^^ ERROR: using calling conventions other than `C` or `cdecl` for varargs functions is unstable
+    f(22, 44);
+}
+
+fn main() {}
diff --git a/src/test/ui/c-variadic/feature-gate-extended_varargs_abi_support.stderr b/src/test/ui/c-variadic/feature-gate-extended_varargs_abi_support.stderr
new file mode 100644
index 000000000000..007d7d7953c9
--- /dev/null
+++ b/src/test/ui/c-variadic/feature-gate-extended_varargs_abi_support.stderr
@@ -0,0 +1,49 @@
+error[E0658]: using calling conventions other than `C` or `cdecl` for varargs functions is unstable
+  --> $DIR/feature-gate-extended_varargs_abi_support.rs:3:14
+   |
+LL | fn efiapi(f: extern "efiapi" fn(usize, ...)) {
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #100189 <https://github.com/rust-lang/rust/issues/100189> for more information
+   = help: add `#![feature(extended_varargs_abi_support)]` to the crate attributes to enable
+
+error[E0045]: C-variadic function must have a compatible calling convention, like `C` or `cdecl`
+  --> $DIR/feature-gate-extended_varargs_abi_support.rs:3:14
+   |
+LL | fn efiapi(f: extern "efiapi" fn(usize, ...)) {
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ C-variadic function must have a compatible calling convention
+
+error[E0658]: using calling conventions other than `C` or `cdecl` for varargs functions is unstable
+  --> $DIR/feature-gate-extended_varargs_abi_support.rs:8:12
+   |
+LL | fn sysv(f: extern "sysv64" fn(usize, ...)) {
+   |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #100189 <https://github.com/rust-lang/rust/issues/100189> for more information
+   = help: add `#![feature(extended_varargs_abi_support)]` to the crate attributes to enable
+
+error[E0045]: C-variadic function must have a compatible calling convention, like `C` or `cdecl`
+  --> $DIR/feature-gate-extended_varargs_abi_support.rs:8:12
+   |
+LL | fn sysv(f: extern "sysv64" fn(usize, ...)) {
+   |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ C-variadic function must have a compatible calling convention
+
+error[E0658]: using calling conventions other than `C` or `cdecl` for varargs functions is unstable
+  --> $DIR/feature-gate-extended_varargs_abi_support.rs:13:11
+   |
+LL | fn win(f: extern "win64" fn(usize, ...)) {
+   |           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #100189 <https://github.com/rust-lang/rust/issues/100189> for more information
+   = help: add `#![feature(extended_varargs_abi_support)]` to the crate attributes to enable
+
+error[E0045]: C-variadic function must have a compatible calling convention, like `C` or `cdecl`
+  --> $DIR/feature-gate-extended_varargs_abi_support.rs:13:11
+   |
+LL | fn win(f: extern "win64" fn(usize, ...)) {
+   |           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ C-variadic function must have a compatible calling convention
+
+error: aborting due to 6 previous errors
+
+Some errors have detailed explanations: E0045, E0658.
+For more information about an error, try `rustc --explain E0045`.
diff --git a/src/test/ui/c-variadic/issue-86053-1.stderr b/src/test/ui/c-variadic/issue-86053-1.stderr
index 60b379faf4e0..075bd1fc488e 100644
--- a/src/test/ui/c-variadic/issue-86053-1.stderr
+++ b/src/test/ui/c-variadic/issue-86053-1.stderr
@@ -66,8 +66,8 @@ LL |     self , ... ,   self ,   self , ... ) where F : FnOnce ( & 'a & 'b usize
    |
   ::: $SRC_DIR/core/src/ops/function.rs:LL:COL
    |
-LL | pub trait Fn<Args>: FnMut<Args> {
-   | ------------------------------- similarly named trait `Fn` defined here
+LL | pub trait Fn<Args: Tuple>: FnMut<Args> {
+   | -------------------------------------- similarly named trait `Fn` defined here
    |
 help: a trait with a similar name exists
    |
diff --git a/src/test/ui/c-variadic/variadic-ffi-1.rs b/src/test/ui/c-variadic/variadic-ffi-1.rs
index a76efd9a2050..24407a71ce69 100644
--- a/src/test/ui/c-variadic/variadic-ffi-1.rs
+++ b/src/test/ui/c-variadic/variadic-ffi-1.rs
@@ -6,7 +6,9 @@
 trait Sized { }
 
 extern "stdcall" {
-    fn printf(_: *const u8, ...); //~ ERROR: variadic function must have C or cdecl calling
+    fn printf(_: *const u8, ...);
+    //~^ ERROR: C-variadic function must have a compatible calling convention,
+    // like C, cdecl, win64, sysv64 or efiapi
 }
 
 extern "C" {
diff --git a/src/test/ui/c-variadic/variadic-ffi-1.stderr b/src/test/ui/c-variadic/variadic-ffi-1.stderr
index 2ffb80f7ef61..4beea83d8a52 100644
--- a/src/test/ui/c-variadic/variadic-ffi-1.stderr
+++ b/src/test/ui/c-variadic/variadic-ffi-1.stderr
@@ -1,17 +1,17 @@
-error[E0045]: C-variadic function must have C or cdecl calling convention
+error[E0045]: C-variadic function must have a compatible calling convention, like `C` or `cdecl`
   --> $DIR/variadic-ffi-1.rs:9:5
    |
 LL |     fn printf(_: *const u8, ...);
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ C-variadics require C or cdecl calling convention
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ C-variadic function must have a compatible calling convention
 
 error[E0060]: this function takes at least 2 arguments but 0 arguments were supplied
-  --> $DIR/variadic-ffi-1.rs:20:9
+  --> $DIR/variadic-ffi-1.rs:22:9
    |
 LL |         foo();
    |         ^^^-- two arguments of type `isize` and `u8` are missing
    |
 note: function defined here
-  --> $DIR/variadic-ffi-1.rs:13:8
+  --> $DIR/variadic-ffi-1.rs:15:8
    |
 LL |     fn foo(f: isize, x: u8, ...);
    |        ^^^
@@ -21,13 +21,13 @@ LL |         foo(/* isize */, /* u8 */);
    |            ~~~~~~~~~~~~~~~~~~~~~~~
 
 error[E0060]: this function takes at least 2 arguments but 1 argument was supplied
-  --> $DIR/variadic-ffi-1.rs:21:9
+  --> $DIR/variadic-ffi-1.rs:23:9
    |
 LL |         foo(1);
    |         ^^^--- an argument of type `u8` is missing
    |
 note: function defined here
-  --> $DIR/variadic-ffi-1.rs:13:8
+  --> $DIR/variadic-ffi-1.rs:15:8
    |
 LL |     fn foo(f: isize, x: u8, ...);
    |        ^^^
@@ -37,7 +37,7 @@ LL |         foo(1, /* u8 */);
    |            ~~~~~~~~~~~~~
 
 error[E0308]: mismatched types
-  --> $DIR/variadic-ffi-1.rs:23:56
+  --> $DIR/variadic-ffi-1.rs:25:56
    |
 LL |         let x: unsafe extern "C" fn(f: isize, x: u8) = foo;
    |                -------------------------------------   ^^^ expected non-variadic fn, found variadic function
@@ -48,7 +48,7 @@ LL |         let x: unsafe extern "C" fn(f: isize, x: u8) = foo;
                  found fn item `unsafe extern "C" fn(_, _, ...) {foo}`
 
 error[E0308]: mismatched types
-  --> $DIR/variadic-ffi-1.rs:24:54
+  --> $DIR/variadic-ffi-1.rs:26:54
    |
 LL |         let y: extern "C" fn(f: isize, x: u8, ...) = bar;
    |                -----------------------------------   ^^^ expected variadic fn, found non-variadic function
@@ -59,37 +59,37 @@ LL |         let y: extern "C" fn(f: isize, x: u8, ...) = bar;
                  found fn item `extern "C" fn(_, _) {bar}`
 
 error[E0617]: can't pass `f32` to variadic function
-  --> $DIR/variadic-ffi-1.rs:26:19
+  --> $DIR/variadic-ffi-1.rs:28:19
    |
 LL |         foo(1, 2, 3f32);
    |                   ^^^^ help: cast the value to `c_double`: `3f32 as c_double`
 
 error[E0617]: can't pass `bool` to variadic function
-  --> $DIR/variadic-ffi-1.rs:27:19
+  --> $DIR/variadic-ffi-1.rs:29:19
    |
 LL |         foo(1, 2, true);
    |                   ^^^^ help: cast the value to `c_int`: `true as c_int`
 
 error[E0617]: can't pass `i8` to variadic function
-  --> $DIR/variadic-ffi-1.rs:28:19
+  --> $DIR/variadic-ffi-1.rs:30:19
    |
 LL |         foo(1, 2, 1i8);
    |                   ^^^ help: cast the value to `c_int`: `1i8 as c_int`
 
 error[E0617]: can't pass `u8` to variadic function
-  --> $DIR/variadic-ffi-1.rs:29:19
+  --> $DIR/variadic-ffi-1.rs:31:19
    |
 LL |         foo(1, 2, 1u8);
    |                   ^^^ help: cast the value to `c_uint`: `1u8 as c_uint`
 
 error[E0617]: can't pass `i16` to variadic function
-  --> $DIR/variadic-ffi-1.rs:30:19
+  --> $DIR/variadic-ffi-1.rs:32:19
    |
 LL |         foo(1, 2, 1i16);
    |                   ^^^^ help: cast the value to `c_int`: `1i16 as c_int`
 
 error[E0617]: can't pass `u16` to variadic function
-  --> $DIR/variadic-ffi-1.rs:31:19
+  --> $DIR/variadic-ffi-1.rs:33:19
    |
 LL |         foo(1, 2, 1u16);
    |                   ^^^^ help: cast the value to `c_uint`: `1u16 as c_uint`
diff --git a/src/test/ui/c-variadic/variadic-ffi-2.rs b/src/test/ui/c-variadic/variadic-ffi-2.rs
index 224ac16f4586..96cea87546e7 100644
--- a/src/test/ui/c-variadic/variadic-ffi-2.rs
+++ b/src/test/ui/c-variadic/variadic-ffi-2.rs
@@ -1,7 +1,20 @@
 // ignore-arm stdcall isn't supported
+#![feature(extended_varargs_abi_support)]
+#![feature(abi_efiapi)]
 
 fn baz(f: extern "stdcall" fn(usize, ...)) {
-    //~^ ERROR: variadic function must have C or cdecl calling convention
+    //~^ ERROR: C-variadic function must have a compatible calling convention,
+    // like C, cdecl, win64, sysv64 or efiapi
+    f(22, 44);
+}
+
+fn sysv(f: extern "sysv64" fn(usize, ...)) {
+    f(22, 44);
+}
+fn win(f: extern "win64" fn(usize, ...)) {
+    f(22, 44);
+}
+fn efiapi(f: extern "efiapi" fn(usize, ...)) {
     f(22, 44);
 }
 
diff --git a/src/test/ui/c-variadic/variadic-ffi-2.stderr b/src/test/ui/c-variadic/variadic-ffi-2.stderr
index 4c8b8d2b2e1a..4e74c9d92278 100644
--- a/src/test/ui/c-variadic/variadic-ffi-2.stderr
+++ b/src/test/ui/c-variadic/variadic-ffi-2.stderr
@@ -1,8 +1,8 @@
-error[E0045]: C-variadic function must have C or cdecl calling convention
-  --> $DIR/variadic-ffi-2.rs:3:11
+error[E0045]: C-variadic function must have a compatible calling convention, like `C`, `cdecl`, `win64`, `sysv64` or `efiapi`
+  --> $DIR/variadic-ffi-2.rs:5:11
    |
 LL | fn baz(f: extern "stdcall" fn(usize, ...)) {
-   |           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ C-variadics require C or cdecl calling convention
+   |           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ C-variadic function must have a compatible calling convention
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/cannot-mutate-captured-non-mut-var.rs b/src/test/ui/cannot-mutate-captured-non-mut-var.rs
index a83884acb1d2..952dab25bf9d 100644
--- a/src/test/ui/cannot-mutate-captured-non-mut-var.rs
+++ b/src/test/ui/cannot-mutate-captured-non-mut-var.rs
@@ -1,8 +1,8 @@
-#![feature(unboxed_closures)]
+#![feature(unboxed_closures, tuple_trait)]
 
 use std::io::Read;
 
-fn to_fn_once<A,F:FnOnce<A>>(f: F) -> F { f }
+fn to_fn_once<A:std::marker::Tuple,F:FnOnce<A>>(f: F) -> F { f }
 
 fn main() {
     let x = 1;
diff --git a/src/test/ui/cast/issue-88621.rs b/src/test/ui/cast/issue-88621.rs
index 9242b80e2293..1679793ee683 100644
--- a/src/test/ui/cast/issue-88621.rs
+++ b/src/test/ui/cast/issue-88621.rs
@@ -1,5 +1,3 @@
-#![feature(arbitrary_enum_discriminant)]
-
 #[repr(u8)]
 enum Kind2 {
     Foo() = 1,
diff --git a/src/test/ui/cast/issue-88621.stderr b/src/test/ui/cast/issue-88621.stderr
index e96d86651523..886145c1bafe 100644
--- a/src/test/ui/cast/issue-88621.stderr
+++ b/src/test/ui/cast/issue-88621.stderr
@@ -1,5 +1,5 @@
 error[E0605]: non-primitive cast: `Kind2` as `u8`
-  --> $DIR/issue-88621.rs:11:13
+  --> $DIR/issue-88621.rs:9:13
    |
 LL |     let _ = Kind2::Foo() as u8;
    |             ^^^^^^^^^^^^^^^^^^ an `as` expression can only be used to convert between primitive types or to coerce to a specific trait object
diff --git a/src/test/ui/cfg/cfg-method-receiver-ok.rs b/src/test/ui/cfg/cfg-method-receiver-ok.rs
new file mode 100644
index 000000000000..61ad3b8c17ab
--- /dev/null
+++ b/src/test/ui/cfg/cfg-method-receiver-ok.rs
@@ -0,0 +1,14 @@
+// check-pass
+
+macro_rules! foo {
+    () => {
+        #[allow(unreachable_patterns)]
+        {
+            123i32
+        }
+    };
+}
+
+fn main() {
+    let _ = foo!().abs();
+}
diff --git a/src/test/ui/cfg/cfg-method-receiver.rs b/src/test/ui/cfg/cfg-method-receiver.rs
index 78a072f503fa..71134ff17b52 100644
--- a/src/test/ui/cfg/cfg-method-receiver.rs
+++ b/src/test/ui/cfg/cfg-method-receiver.rs
@@ -7,6 +7,5 @@ macro_rules! cbor_map {
 
 fn main() {
     cbor_map! { #[cfg(test)] 4};
-    //~^ ERROR attributes on expressions are experimental
-    //~| ERROR removing an expression is not supported in this position
+    //~^ ERROR removing an expression is not supported in this position
 }
diff --git a/src/test/ui/cfg/cfg-method-receiver.stderr b/src/test/ui/cfg/cfg-method-receiver.stderr
index 517fc8168e72..5767a7c1b4b1 100644
--- a/src/test/ui/cfg/cfg-method-receiver.stderr
+++ b/src/test/ui/cfg/cfg-method-receiver.stderr
@@ -1,12 +1,3 @@
-error[E0658]: attributes on expressions are experimental
-  --> $DIR/cfg-method-receiver.rs:9:17
-   |
-LL |     cbor_map! { #[cfg(test)] 4};
-   |                 ^^^^^^^^^^^^
-   |
-   = note: see issue #15701 <https://github.com/rust-lang/rust/issues/15701> for more information
-   = help: add `#![feature(stmt_expr_attributes)]` to the crate attributes to enable
-
 error: removing an expression is not supported in this position
   --> $DIR/cfg-method-receiver.rs:9:17
    |
@@ -28,7 +19,6 @@ help: you must specify a concrete type for this numeric value, like `i32`
 LL |     cbor_map! { #[cfg(test)] 4_i32};
    |                              ~~~~~
 
-error: aborting due to 3 previous errors
+error: aborting due to 2 previous errors
 
-Some errors have detailed explanations: E0658, E0689.
-For more information about an error, try `rustc --explain E0658`.
+For more information about this error, try `rustc --explain E0689`.
diff --git a/src/test/ui/chalkify/closure.rs b/src/test/ui/chalkify/closure.rs
index 81114d491d78..568e2e30c418 100644
--- a/src/test/ui/chalkify/closure.rs
+++ b/src/test/ui/chalkify/closure.rs
@@ -1,4 +1,3 @@
-// check-fail
 // compile-flags: -Z chalk
 
 fn main() -> () {
diff --git a/src/test/ui/chalkify/closure.stderr b/src/test/ui/chalkify/closure.stderr
index 515e0cf01429..a33c0ba0d37c 100644
--- a/src/test/ui/chalkify/closure.stderr
+++ b/src/test/ui/chalkify/closure.stderr
@@ -1,5 +1,5 @@
 error[E0382]: borrow of moved value: `b`
-  --> $DIR/closure.rs:28:5
+  --> $DIR/closure.rs:27:5
    |
 LL |     let mut c = b;
    |                 - value moved here
@@ -8,7 +8,7 @@ LL |     b();
    |     ^ value borrowed here after move
    |
 note: closure cannot be moved more than once as it is not `Copy` due to moving the variable `a` out of its environment
-  --> $DIR/closure.rs:21:9
+  --> $DIR/closure.rs:20:9
    |
 LL |         a = 1;
    |         ^
diff --git a/src/test/ui/check-cfg/well-known-values.stderr b/src/test/ui/check-cfg/well-known-values.stderr
index 4ec74494fe09..6c0dc05ba233 100644
--- a/src/test/ui/check-cfg/well-known-values.stderr
+++ b/src/test/ui/check-cfg/well-known-values.stderr
@@ -6,7 +6,7 @@ LL | #[cfg(target_os = "linuz")]
    |                   |
    |                   help: did you mean: `"linux"`
    |
-   = note: expected values for `target_os` are: android, cuda, dragonfly, emscripten, espidf, freebsd, fuchsia, haiku, hermit, horizon, illumos, ios, l4re, linux, macos, netbsd, none, openbsd, psp, redox, solaris, solid_asp3, tvos, uefi, unknown, vxworks, wasi, watchos, windows, xous
+   = note: expected values for `target_os` are: android, cuda, dragonfly, emscripten, espidf, freebsd, fuchsia, haiku, hermit, horizon, illumos, ios, l4re, linux, macos, netbsd, none, nto, openbsd, psp, redox, solaris, solid_asp3, tvos, uefi, unknown, vxworks, wasi, watchos, windows, xous
    = note: `#[warn(unexpected_cfgs)]` on by default
 
 warning: unexpected `cfg` condition value
diff --git a/src/test/ui/cleanup-rvalue-scopes-cf.stderr b/src/test/ui/cleanup-rvalue-scopes-cf.stderr
index 40f14c389842..425cd75141ce 100644
--- a/src/test/ui/cleanup-rvalue-scopes-cf.stderr
+++ b/src/test/ui/cleanup-rvalue-scopes-cf.stderr
@@ -4,7 +4,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     let x1 = arg(&AddFlags(1));
    |                   ^^^^^^^^^^^ - temporary value is freed at the end of this statement
    |                   |
-   |                   creates a temporary which is freed while still in use
+   |                   creates a temporary value which is freed while still in use
 ...
 LL |     (x1, x2, x3, x4, x5, x6, x7);
    |      -- borrow later used here
@@ -21,7 +21,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     let x2 = AddFlags(1).get();
    |              ^^^^^^^^^^^      - temporary value is freed at the end of this statement
    |              |
-   |              creates a temporary which is freed while still in use
+   |              creates a temporary value which is freed while still in use
 ...
 LL |     (x1, x2, x3, x4, x5, x6, x7);
    |          -- borrow later used here
@@ -38,7 +38,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     let x3 = &*arg(&AddFlags(1));
    |                     ^^^^^^^^^^^ - temporary value is freed at the end of this statement
    |                     |
-   |                     creates a temporary which is freed while still in use
+   |                     creates a temporary value which is freed while still in use
 ...
 LL |     (x1, x2, x3, x4, x5, x6, x7);
    |              -- borrow later used here
@@ -55,7 +55,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     let ref x4 = *arg(&AddFlags(1));
    |                        ^^^^^^^^^^^ - temporary value is freed at the end of this statement
    |                        |
-   |                        creates a temporary which is freed while still in use
+   |                        creates a temporary value which is freed while still in use
 ...
 LL |     (x1, x2, x3, x4, x5, x6, x7);
    |                  -- borrow later used here
@@ -72,7 +72,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     let &ref x5 = arg(&AddFlags(1));
    |                        ^^^^^^^^^^^ - temporary value is freed at the end of this statement
    |                        |
-   |                        creates a temporary which is freed while still in use
+   |                        creates a temporary value which is freed while still in use
 ...
 LL |     (x1, x2, x3, x4, x5, x6, x7);
    |                      -- borrow later used here
@@ -89,7 +89,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     let x6 = AddFlags(1).get();
    |              ^^^^^^^^^^^      - temporary value is freed at the end of this statement
    |              |
-   |              creates a temporary which is freed while still in use
+   |              creates a temporary value which is freed while still in use
 ...
 LL |     (x1, x2, x3, x4, x5, x6, x7);
    |                          -- borrow later used here
@@ -106,7 +106,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     let StackBox { f: x7 } = StackBox { f: AddFlags(1).get() };
    |                                            ^^^^^^^^^^^        - temporary value is freed at the end of this statement
    |                                            |
-   |                                            creates a temporary which is freed while still in use
+   |                                            creates a temporary value which is freed while still in use
 LL |
 LL |     (x1, x2, x3, x4, x5, x6, x7);
    |                              -- borrow later used here
diff --git a/src/test/ui/closures/2229_closure_analysis/match/issue-87097.stderr b/src/test/ui/closures/2229_closure_analysis/match/issue-87097.stderr
index 384010859713..39ec71ba22a1 100644
--- a/src/test/ui/closures/2229_closure_analysis/match/issue-87097.stderr
+++ b/src/test/ui/closures/2229_closure_analysis/match/issue-87097.stderr
@@ -16,7 +16,7 @@ LL | /     || match out_ref {
 LL | |         Variant::A => (),
 LL | |         Variant::B => (),
 LL | |     };
-   | |______^
+   | |_____^
    |
    = note: closures are lazy and do nothing unless called
    = note: `#[warn(unused_must_use)]` on by default
@@ -28,7 +28,7 @@ LL | /     || match here.field {
 LL | |         Variant::A => (),
 LL | |         Variant::B => (),
 LL | |     };
-   | |______^
+   | |_____^
    |
    = note: closures are lazy and do nothing unless called
 
diff --git a/src/test/ui/closures/binder/late-bound-in-body.rs b/src/test/ui/closures/binder/late-bound-in-body.rs
new file mode 100644
index 000000000000..bb5c7552fdaa
--- /dev/null
+++ b/src/test/ui/closures/binder/late-bound-in-body.rs
@@ -0,0 +1,9 @@
+// check-pass
+
+#![feature(closure_lifetime_binder)]
+
+fn main() {
+    let _ = for<'a> || -> () {
+        let _: &'a bool = &true;
+    };
+}
diff --git a/src/test/ui/closures/binder/nested-closures-regions.rs b/src/test/ui/closures/binder/nested-closures-regions.rs
new file mode 100644
index 000000000000..6bfc6c80b788
--- /dev/null
+++ b/src/test/ui/closures/binder/nested-closures-regions.rs
@@ -0,0 +1,9 @@
+// check-pass
+
+#![feature(closure_lifetime_binder)]
+#![feature(rustc_attrs)]
+
+#[rustc_regions]
+fn main() {
+    for<'a> || -> () { for<'c> |_: &'a ()| -> () {}; };
+}
diff --git a/src/test/ui/closures/binder/nested-closures-regions.stderr b/src/test/ui/closures/binder/nested-closures-regions.stderr
new file mode 100644
index 000000000000..b385e0ed6e0a
--- /dev/null
+++ b/src/test/ui/closures/binder/nested-closures-regions.stderr
@@ -0,0 +1,38 @@
+note: external requirements
+  --> $DIR/nested-closures-regions.rs:8:24
+   |
+LL |     for<'a> || -> () { for<'c> |_: &'a ()| -> () {}; };
+   |                        ^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: defining type: main::{closure#0}::{closure#0} with closure substs [
+               i8,
+               extern "rust-call" fn((&(),)),
+               (),
+           ]
+   = note: late-bound region is '_#4r
+   = note: late-bound region is '_#2r
+   = note: number of external vids: 3
+   = note: where '_#1r: '_#2r
+   = note: where '_#2r: '_#1r
+
+note: no external requirements
+  --> $DIR/nested-closures-regions.rs:8:5
+   |
+LL |     for<'a> || -> () { for<'c> |_: &'a ()| -> () {}; };
+   |     ^^^^^^^^^^^^^^^^
+   |
+   = note: defining type: main::{closure#0} with closure substs [
+               i8,
+               extern "rust-call" fn(()),
+               (),
+           ]
+   = note: late-bound region is '_#2r
+
+note: no external requirements
+  --> $DIR/nested-closures-regions.rs:7:1
+   |
+LL | fn main() {
+   | ^^^^^^^^^
+   |
+   = note: defining type: main
+
diff --git a/src/test/ui/closures/binder/nested-closures.rs b/src/test/ui/closures/binder/nested-closures.rs
new file mode 100644
index 000000000000..b3c36e7eebb7
--- /dev/null
+++ b/src/test/ui/closures/binder/nested-closures.rs
@@ -0,0 +1,7 @@
+// check-pass
+
+#![feature(closure_lifetime_binder)]
+
+fn main() {
+    for<'a> || -> () { for<'c> |_: &'a ()| -> () {}; };
+}
diff --git a/src/test/ui/closures/closure-array-break-length.stderr b/src/test/ui/closures/closure-array-break-length.stderr
index 2b8ab9bfc441..7e0b0027a6f0 100644
--- a/src/test/ui/closures/closure-array-break-length.stderr
+++ b/src/test/ui/closures/closure-array-break-length.stderr
@@ -10,11 +10,11 @@ error[E0268]: `continue` outside of a loop
 LL |     while |_: [_; continue]| {} {}
    |                   ^^^^^^^^ cannot `continue` outside of a loop
 
-error[E0268]: `break` outside of a loop
+error[E0268]: `break` outside of a loop or labeled block
   --> $DIR/closure-array-break-length.rs:6:19
    |
 LL |     while |_: [_; break]| {} {}
-   |                   ^^^^^ cannot `break` outside of a loop
+   |                   ^^^^^ cannot `break` outside of a loop or labeled block
 
 error: aborting due to 3 previous errors
 
diff --git a/src/test/ui/closures/issue-23012-supertrait-signature-inference.rs b/src/test/ui/closures/issue-23012-supertrait-signature-inference.rs
new file mode 100644
index 000000000000..5899b703e7c1
--- /dev/null
+++ b/src/test/ui/closures/issue-23012-supertrait-signature-inference.rs
@@ -0,0 +1,29 @@
+// check-pass
+// Checks that we can infer a closure signature even if the `FnOnce` bound is
+// a supertrait of the obligations we have currently registered for the Ty var.
+
+pub trait Receive<T, E>: FnOnce(Result<T, E>) {
+    fn receive(self, res: Result<T, E>);
+}
+
+impl<T, E, F: FnOnce(Result<T, E>)> Receive<T, E> for F {
+    fn receive(self, res: Result<T, E>) {
+        self(res)
+    }
+}
+
+pub trait Async<T, E> {
+    fn receive<F: Receive<T, E>>(self, f: F);
+}
+
+impl<T, E> Async<T, E> for Result<T, E> {
+    fn receive<F: Receive<T, E>>(self, f: F) {
+        f(self)
+    }
+}
+
+pub fn main() {
+    Ok::<u32, ()>(123).receive(|res| {
+        res.unwrap();
+    });
+}
diff --git a/src/test/ui/closures/issue-78720.stderr b/src/test/ui/closures/issue-78720.stderr
index 3dd138772983..da3f539a0071 100644
--- a/src/test/ui/closures/issue-78720.stderr
+++ b/src/test/ui/closures/issue-78720.stderr
@@ -12,8 +12,8 @@ LL |     _func: F,
    |
   ::: $SRC_DIR/core/src/ops/function.rs:LL:COL
    |
-LL | pub trait Fn<Args>: FnMut<Args> {
-   | ------------------------------- similarly named trait `Fn` defined here
+LL | pub trait Fn<Args: Tuple>: FnMut<Args> {
+   | -------------------------------------- similarly named trait `Fn` defined here
    |
 help: a trait with a similar name exists
    |
diff --git a/src/test/ui/closures/supertrait-hint-references-assoc-ty.rs b/src/test/ui/closures/supertrait-hint-references-assoc-ty.rs
new file mode 100644
index 000000000000..270bf14c35ec
--- /dev/null
+++ b/src/test/ui/closures/supertrait-hint-references-assoc-ty.rs
@@ -0,0 +1,17 @@
+// check-pass
+
+pub trait Fn0: Fn(i32) -> Self::Out {
+    type Out;
+}
+
+impl<F: Fn(i32) -> ()> Fn0 for F {
+    type Out = ();
+}
+
+pub fn closure_typer(_: impl Fn0) {}
+
+fn main() {
+    closure_typer(move |x| {
+        let _: i64 = x.into();
+    });
+}
diff --git a/src/test/ui/codegen/issue-99551.rs b/src/test/ui/codegen/issue-99551.rs
index f24874c992ea..b223aff4e949 100644
--- a/src/test/ui/codegen/issue-99551.rs
+++ b/src/test/ui/codegen/issue-99551.rs
@@ -1,6 +1,5 @@
 // build-pass
 #![feature(trait_upcasting)]
-#![allow(incomplete_features)]
 
 pub trait A {}
 pub trait B {}
diff --git a/src/test/ui/coercion/coerce-block-tail-26978.rs b/src/test/ui/coercion/coerce-block-tail-26978.rs
new file mode 100644
index 000000000000..01c8ab5a839f
--- /dev/null
+++ b/src/test/ui/coercion/coerce-block-tail-26978.rs
@@ -0,0 +1,11 @@
+// check-fail
+fn f(_: &i32) {}
+
+fn main() {
+    let x = Box::new(1i32);
+
+    f(&x);
+    f(&(x));
+    f(&{x});
+    //~^ ERROR mismatched types
+}
diff --git a/src/test/ui/coercion/coerce-block-tail-26978.stderr b/src/test/ui/coercion/coerce-block-tail-26978.stderr
new file mode 100644
index 000000000000..384debd487c5
--- /dev/null
+++ b/src/test/ui/coercion/coerce-block-tail-26978.stderr
@@ -0,0 +1,16 @@
+error[E0308]: mismatched types
+  --> $DIR/coerce-block-tail-26978.rs:9:9
+   |
+LL |     f(&{x});
+   |         ^ expected `i32`, found struct `Box`
+   |
+   = note: expected type `i32`
+            found struct `Box<i32>`
+help: consider unboxing the value
+   |
+LL |     f(&{*x});
+   |         +
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/ui/coercion/coerce-block-tail-57749.rs b/src/test/ui/coercion/coerce-block-tail-57749.rs
new file mode 100644
index 000000000000..79b5b33233b3
--- /dev/null
+++ b/src/test/ui/coercion/coerce-block-tail-57749.rs
@@ -0,0 +1,35 @@
+// check-fail
+use std::ops::Deref;
+
+fn main() {
+    fn save(who: &str) {
+        println!("I'll save you, {}!", who);
+    }
+
+    struct Madoka;
+
+    impl Deref for Madoka {
+        type Target = str;
+        fn deref(&self) -> &Self::Target {
+            "Madoka"
+        }
+    }
+
+    save(&{ Madoka });
+
+    fn reset(how: &u32) {
+        println!("Reset {} times", how);
+    }
+
+    struct Homura;
+
+    impl Deref for Homura {
+        type Target = u32;
+        fn deref(&self) -> &Self::Target {
+            &42
+        }
+    }
+
+    reset(&{ Homura });
+    //~^ ERROR mismatched types
+}
diff --git a/src/test/ui/coercion/coerce-block-tail-57749.stderr b/src/test/ui/coercion/coerce-block-tail-57749.stderr
new file mode 100644
index 000000000000..d5660c81dbd3
--- /dev/null
+++ b/src/test/ui/coercion/coerce-block-tail-57749.stderr
@@ -0,0 +1,14 @@
+error[E0308]: mismatched types
+  --> $DIR/coerce-block-tail-57749.rs:33:14
+   |
+LL |     reset(&{ Homura });
+   |              ^^^^^^ expected `u32`, found struct `Homura`
+   |
+help: consider dereferencing the type
+   |
+LL |     reset(&{ *Homura });
+   |              +
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/ui/coercion/coerce-block-tail-83783.rs b/src/test/ui/coercion/coerce-block-tail-83783.rs
new file mode 100644
index 000000000000..18c8ae3bbbad
--- /dev/null
+++ b/src/test/ui/coercion/coerce-block-tail-83783.rs
@@ -0,0 +1,13 @@
+// check-fail
+// edition:2018
+fn _consume_reference<T: ?Sized>(_: &T) {}
+
+async fn _foo() {
+    _consume_reference::<i32>(&Box::new(7_i32));
+    _consume_reference::<i32>(&async { Box::new(7_i32) }.await);
+    //~^ ERROR mismatched types
+    _consume_reference::<[i32]>(&vec![7_i32]);
+    _consume_reference::<[i32]>(&async { vec![7_i32] }.await);
+}
+
+fn main() { }
diff --git a/src/test/ui/coercion/coerce-block-tail-83783.stderr b/src/test/ui/coercion/coerce-block-tail-83783.stderr
new file mode 100644
index 000000000000..5f53606ce222
--- /dev/null
+++ b/src/test/ui/coercion/coerce-block-tail-83783.stderr
@@ -0,0 +1,12 @@
+error[E0308]: mismatched types
+  --> $DIR/coerce-block-tail-83783.rs:7:32
+   |
+LL |     _consume_reference::<i32>(&async { Box::new(7_i32) }.await);
+   |                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `i32`, found struct `Box`
+   |
+   = note: expected type `i32`
+            found struct `Box<i32>`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/ui/coercion/coerce-block-tail-83850.rs b/src/test/ui/coercion/coerce-block-tail-83850.rs
new file mode 100644
index 000000000000..77fdf9998333
--- /dev/null
+++ b/src/test/ui/coercion/coerce-block-tail-83850.rs
@@ -0,0 +1,7 @@
+// check-fail
+fn f(_: &[i32]) {}
+
+fn main() {
+    f(&Box::new([1, 2]));
+    //~^ ERROR mismatched types
+}
diff --git a/src/test/ui/coercion/coerce-block-tail-83850.stderr b/src/test/ui/coercion/coerce-block-tail-83850.stderr
new file mode 100644
index 000000000000..bbf607543704
--- /dev/null
+++ b/src/test/ui/coercion/coerce-block-tail-83850.stderr
@@ -0,0 +1,19 @@
+error[E0308]: mismatched types
+  --> $DIR/coerce-block-tail-83850.rs:5:7
+   |
+LL |     f(&Box::new([1, 2]));
+   |     - ^^^^^^^^^^^^^^^^^ expected slice `[i32]`, found struct `Box`
+   |     |
+   |     arguments to this function are incorrect
+   |
+   = note: expected reference `&[i32]`
+              found reference `&Box<[{integer}; 2]>`
+note: function defined here
+  --> $DIR/coerce-block-tail-83850.rs:2:4
+   |
+LL | fn f(_: &[i32]) {}
+   |    ^ ---------
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/ui/coercion/coerce-block-tail.rs b/src/test/ui/coercion/coerce-block-tail.rs
new file mode 100644
index 000000000000..dcbcd3762862
--- /dev/null
+++ b/src/test/ui/coercion/coerce-block-tail.rs
@@ -0,0 +1,6 @@
+// check-fail
+fn main() {
+    let _: &str = & { String::from("hahah")};
+    let _: &i32 = & { Box::new(1i32) };
+    //~^ ERROR mismatched types
+}
diff --git a/src/test/ui/coercion/coerce-block-tail.stderr b/src/test/ui/coercion/coerce-block-tail.stderr
new file mode 100644
index 000000000000..318cf75867b4
--- /dev/null
+++ b/src/test/ui/coercion/coerce-block-tail.stderr
@@ -0,0 +1,16 @@
+error[E0308]: mismatched types
+  --> $DIR/coerce-block-tail.rs:4:23
+   |
+LL |     let _: &i32 = & { Box::new(1i32) };
+   |                       ^^^^^^^^^^^^^^ expected `i32`, found struct `Box`
+   |
+   = note: expected type `i32`
+            found struct `Box<i32>`
+help: consider unboxing the value
+   |
+LL |     let _: &i32 = & { *Box::new(1i32) };
+   |                       +
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/ui/coercion/issue-36007.rs b/src/test/ui/coercion/issue-36007.rs
new file mode 100644
index 000000000000..78812df870d0
--- /dev/null
+++ b/src/test/ui/coercion/issue-36007.rs
@@ -0,0 +1,20 @@
+// check-pass
+#![feature(coerce_unsized, unsize)]
+
+use std::marker::Unsize;
+use std::ops::CoerceUnsized;
+
+struct Foo<T: ?Sized>(Box<T>);
+
+impl<T> CoerceUnsized<Foo<dyn Baz>> for Foo<T> where T: Unsize<dyn Baz> {}
+
+struct Bar;
+
+trait Baz {}
+
+impl Baz for Bar {}
+
+fn main() {
+    let foo = Foo(Box::new(Bar));
+    let foobar: Foo<Bar> = foo;
+}
diff --git a/src/test/ui/coherence/coherence-blanket-conflicts-with-specific-cross-crate.stderr b/src/test/ui/coherence/coherence-blanket-conflicts-with-specific-cross-crate.stderr
index c25c43692928..4d7872598b1e 100644
--- a/src/test/ui/coherence/coherence-blanket-conflicts-with-specific-cross-crate.stderr
+++ b/src/test/ui/coherence/coherence-blanket-conflicts-with-specific-cross-crate.stderr
@@ -1,4 +1,4 @@
-error[E0119]: conflicting implementations of trait `go_trait::GoMut` for type `MyThingy`
+error[E0119]: conflicting implementations of trait `GoMut` for type `MyThingy`
   --> $DIR/coherence-blanket-conflicts-with-specific-cross-crate.rs:15:1
    |
 LL | impl GoMut for MyThingy {
diff --git a/src/test/ui/coherence/coherence-conflicting-negative-trait-impl.stderr b/src/test/ui/coherence/coherence-conflicting-negative-trait-impl.stderr
index 1110197734f7..2463f38a9225 100644
--- a/src/test/ui/coherence/coherence-conflicting-negative-trait-impl.stderr
+++ b/src/test/ui/coherence/coherence-conflicting-negative-trait-impl.stderr
@@ -1,4 +1,4 @@
-error[E0751]: found both positive and negative implementation of trait `std::marker::Send` for type `TestType<_>`:
+error[E0751]: found both positive and negative implementation of trait `Send` for type `TestType<_>`:
   --> $DIR/coherence-conflicting-negative-trait-impl.rs:11:1
    |
 LL | unsafe impl<T: MyTrait + 'static> Send for TestType<T> {}
@@ -7,7 +7,7 @@ LL |
 LL | impl<T: MyTrait> !Send for TestType<T> {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ negative implementation here
 
-error[E0119]: conflicting implementations of trait `std::marker::Send` for type `TestType<_>`
+error[E0119]: conflicting implementations of trait `Send` for type `TestType<_>`
   --> $DIR/coherence-conflicting-negative-trait-impl.rs:13:1
    |
 LL | unsafe impl<T: MyTrait + 'static> Send for TestType<T> {}
diff --git a/src/test/ui/coherence/coherence-default-trait-impl.stderr b/src/test/ui/coherence/coherence-default-trait-impl.stderr
index b08ccb087d91..632018782725 100644
--- a/src/test/ui/coherence/coherence-default-trait-impl.stderr
+++ b/src/test/ui/coherence/coherence-default-trait-impl.stderr
@@ -3,12 +3,24 @@ error[E0199]: implementing the trait `MySafeTrait` is not unsafe
    |
 LL | unsafe impl MySafeTrait for Foo {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: remove `unsafe` from this trait implementation
+   |
+LL - unsafe impl MySafeTrait for Foo {}
+LL + impl MySafeTrait for Foo {}
+   |
 
 error[E0200]: the trait `MyUnsafeTrait` requires an `unsafe impl` declaration
   --> $DIR/coherence-default-trait-impl.rs:13:1
    |
 LL | impl MyUnsafeTrait for Foo {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: the trait `MyUnsafeTrait` enforces invariants that the compiler can't check. Review the trait documentation and make sure this implementation upholds those invariants before adding the `unsafe` keyword
+help: add `unsafe` to this trait implementation
+   |
+LL | unsafe impl MyUnsafeTrait for Foo {}
+   | ++++++
 
 error: aborting due to 2 previous errors
 
diff --git a/src/test/ui/coherence/coherence-impls-copy.stderr b/src/test/ui/coherence/coherence-impls-copy.stderr
index 86356af25643..d40ffc48a29f 100644
--- a/src/test/ui/coherence/coherence-impls-copy.stderr
+++ b/src/test/ui/coherence/coherence-impls-copy.stderr
@@ -9,7 +9,7 @@ LL | impl Copy for i32 {}
    |
    = note: define and implement a trait or new type instead
 
-error[E0119]: conflicting implementations of trait `std::marker::Copy` for type `&NotSync`
+error[E0119]: conflicting implementations of trait `Copy` for type `&NotSync`
   --> $DIR/coherence-impls-copy.rs:28:1
    |
 LL | impl Copy for &'static NotSync {}
diff --git a/src/test/ui/coherence/coherence-overlap-issue-23516.stderr b/src/test/ui/coherence/coherence-overlap-issue-23516.stderr
index 85eb189e10ee..cd398426704c 100644
--- a/src/test/ui/coherence/coherence-overlap-issue-23516.stderr
+++ b/src/test/ui/coherence/coherence-overlap-issue-23516.stderr
@@ -1,10 +1,10 @@
-error[E0119]: conflicting implementations of trait `Sweet` for type `std::boxed::Box<_>`
+error[E0119]: conflicting implementations of trait `Sweet` for type `Box<_>`
   --> $DIR/coherence-overlap-issue-23516.rs:8:1
    |
 LL | impl<T:Sugar> Sweet for T { }
    | ------------------------- first implementation here
 LL | impl<U:Sugar> Sweet for Box<U> { }
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `std::boxed::Box<_>`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `Box<_>`
    |
    = note: downstream crates may implement trait `Sugar` for type `std::boxed::Box<_>`
 
diff --git a/src/test/ui/coherence/coherence-projection-conflict-ty-param.stderr b/src/test/ui/coherence/coherence-projection-conflict-ty-param.stderr
index 6492747bb261..94d242eaac43 100644
--- a/src/test/ui/coherence/coherence-projection-conflict-ty-param.stderr
+++ b/src/test/ui/coherence/coherence-projection-conflict-ty-param.stderr
@@ -1,11 +1,11 @@
-error[E0119]: conflicting implementations of trait `Foo<_>` for type `std::option::Option<_>`
+error[E0119]: conflicting implementations of trait `Foo<_>` for type `Option<_>`
   --> $DIR/coherence-projection-conflict-ty-param.rs:10:1
    |
 LL | impl <P, T: Foo<P>> Foo<P> for Option<T> {}
    | ---------------------------------------- first implementation here
 LL |
 LL | impl<T, U> Foo<T> for Option<U> { }
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `std::option::Option<_>`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `Option<_>`
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/coherence/coherence-wasm-bindgen.stderr b/src/test/ui/coherence/coherence-wasm-bindgen.stderr
index cfcc21240e4e..89615f0fbc63 100644
--- a/src/test/ui/coherence/coherence-wasm-bindgen.stderr
+++ b/src/test/ui/coherence/coherence-wasm-bindgen.stderr
@@ -1,11 +1,11 @@
-error: conflicting implementations of trait `IntoWasmAbi` for type `&dyn std::ops::Fn(&_) -> _`
+error: conflicting implementations of trait `IntoWasmAbi` for type `&dyn Fn(&_) -> _`
   --> $DIR/coherence-wasm-bindgen.rs:28:1
    |
 LL | impl<'a, 'b, A, R> IntoWasmAbi for &'a (dyn Fn(A) -> R + 'b)
    | ------------------------------------------------------------ first implementation here
 ...
 LL | impl<'a, 'b, A, R> IntoWasmAbi for &'a (dyn for<'x> Fn(&'x A) -> R + 'b)
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `&dyn std::ops::Fn(&_) -> _`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `&dyn Fn(&_) -> _`
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #56105 <https://github.com/rust-lang/rust/issues/56105>
diff --git a/src/test/ui/coherence/coherence_copy_like_err_fundamental_struct_tuple.stderr b/src/test/ui/coherence/coherence_copy_like_err_fundamental_struct_tuple.stderr
index db730650185e..93486fa5f360 100644
--- a/src/test/ui/coherence/coherence_copy_like_err_fundamental_struct_tuple.stderr
+++ b/src/test/ui/coherence/coherence_copy_like_err_fundamental_struct_tuple.stderr
@@ -1,11 +1,11 @@
-error[E0119]: conflicting implementations of trait `MyTrait` for type `lib::MyFundamentalStruct<(MyType,)>`
+error[E0119]: conflicting implementations of trait `MyTrait` for type `MyFundamentalStruct<(MyType,)>`
   --> $DIR/coherence_copy_like_err_fundamental_struct_tuple.rs:16:1
    |
 LL | impl<T: lib::MyCopy> MyTrait for T { }
    | ---------------------------------- first implementation here
 ...
 LL | impl MyTrait for lib::MyFundamentalStruct<(MyType,)> { }
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `lib::MyFundamentalStruct<(MyType,)>`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `MyFundamentalStruct<(MyType,)>`
    |
    = note: upstream crates may add a new impl of trait `lib::MyCopy` for type `lib::MyFundamentalStruct<(MyType,)>` in future versions
 
diff --git a/src/test/ui/coherence/coherence_copy_like_err_struct.stderr b/src/test/ui/coherence/coherence_copy_like_err_struct.stderr
index 3bc3dffda5d1..7432733b932a 100644
--- a/src/test/ui/coherence/coherence_copy_like_err_struct.stderr
+++ b/src/test/ui/coherence/coherence_copy_like_err_struct.stderr
@@ -1,11 +1,11 @@
-error[E0119]: conflicting implementations of trait `MyTrait` for type `lib::MyStruct<MyType>`
+error[E0119]: conflicting implementations of trait `MyTrait` for type `MyStruct<MyType>`
   --> $DIR/coherence_copy_like_err_struct.rs:19:1
    |
 LL | impl<T: lib::MyCopy> MyTrait for T { }
    | ---------------------------------- first implementation here
 ...
 LL | impl MyTrait for lib::MyStruct<MyType> { }
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `lib::MyStruct<MyType>`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `MyStruct<MyType>`
    |
    = note: upstream crates may add a new impl of trait `lib::MyCopy` for type `lib::MyStruct<MyType>` in future versions
 
diff --git a/src/test/ui/coherence/inter-crate-ambiguity-causes-notes.stderr b/src/test/ui/coherence/inter-crate-ambiguity-causes-notes.stderr
index 038a0199a8f2..4ddd712b27c8 100644
--- a/src/test/ui/coherence/inter-crate-ambiguity-causes-notes.stderr
+++ b/src/test/ui/coherence/inter-crate-ambiguity-causes-notes.stderr
@@ -1,4 +1,4 @@
-error[E0119]: conflicting implementations of trait `std::convert::From<()>` for type `S`
+error[E0119]: conflicting implementations of trait `From<()>` for type `S`
   --> $DIR/inter-crate-ambiguity-causes-notes.rs:9:1
    |
 LL | impl From<()> for S {
diff --git a/src/test/ui/coherence/strict-coherence-needs-negative-coherence.rs b/src/test/ui/coherence/strict-coherence-needs-negative-coherence.rs
new file mode 100644
index 000000000000..221683dd56f4
--- /dev/null
+++ b/src/test/ui/coherence/strict-coherence-needs-negative-coherence.rs
@@ -0,0 +1,7 @@
+#![feature(rustc_attrs)]
+
+#[rustc_strict_coherence]
+trait Foo {}
+//~^ ERROR to use `strict_coherence` on this trait, the `with_negative_coherence` feature must be enabled
+
+fn main() {}
diff --git a/src/test/ui/coherence/strict-coherence-needs-negative-coherence.stderr b/src/test/ui/coherence/strict-coherence-needs-negative-coherence.stderr
new file mode 100644
index 000000000000..b5472928778e
--- /dev/null
+++ b/src/test/ui/coherence/strict-coherence-needs-negative-coherence.stderr
@@ -0,0 +1,10 @@
+error: to use `strict_coherence` on this trait, the `with_negative_coherence` feature must be enabled
+  --> $DIR/strict-coherence-needs-negative-coherence.rs:4:1
+   |
+LL | #[rustc_strict_coherence]
+   | ------------------------- due to this attribute
+LL | trait Foo {}
+   | ^^^^^^^^^
+
+error: aborting due to previous error
+
diff --git a/src/test/ui/compiletest-self-test/compile-flags-last.rs b/src/test/ui/compiletest-self-test/compile-flags-last.rs
new file mode 100644
index 000000000000..232df10f1a84
--- /dev/null
+++ b/src/test/ui/compiletest-self-test/compile-flags-last.rs
@@ -0,0 +1,7 @@
+// Check that the arguments provided through `// compile-flags` are added last to the command line
+// in UI tests. To ensure that we invoke rustc with a flag that expects an argument withut actually
+// providing it. If the compile-flags are not last, the test will fail as rustc will interpret the
+// next flag as the argument of this flag.
+//
+// compile-flags: --cap-lints
+// error-pattern: Argument to option 'cap-lints' missing
diff --git a/src/test/ui/compiletest-self-test/compile-flags-last.stderr b/src/test/ui/compiletest-self-test/compile-flags-last.stderr
new file mode 100644
index 000000000000..d8d40a7d9f11
--- /dev/null
+++ b/src/test/ui/compiletest-self-test/compile-flags-last.stderr
@@ -0,0 +1,2 @@
+error: Argument to option 'cap-lints' missing
+
diff --git a/src/test/ui/ui-testing-optout.rs b/src/test/ui/compiletest-self-test/ui-testing-optout.rs
similarity index 100%
rename from src/test/ui/ui-testing-optout.rs
rename to src/test/ui/compiletest-self-test/ui-testing-optout.rs
diff --git a/src/test/ui/ui-testing-optout.stderr b/src/test/ui/compiletest-self-test/ui-testing-optout.stderr
similarity index 100%
rename from src/test/ui/ui-testing-optout.stderr
rename to src/test/ui/compiletest-self-test/ui-testing-optout.stderr
diff --git a/src/test/ui/conditional-compilation/cfg-attr-multi-true.stderr b/src/test/ui/conditional-compilation/cfg-attr-multi-true.stderr
index 5f278f94b93b..fbfcd45652f1 100644
--- a/src/test/ui/conditional-compilation/cfg-attr-multi-true.stderr
+++ b/src/test/ui/conditional-compilation/cfg-attr-multi-true.stderr
@@ -28,7 +28,7 @@ warning: unused `MustUseDeprecated` that must be used
   --> $DIR/cfg-attr-multi-true.rs:19:5
    |
 LL |     MustUseDeprecated::new();
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^
    |
 note: the lint level is defined here
   --> $DIR/cfg-attr-multi-true.rs:7:9
diff --git a/src/test/ui/conditional-compilation/cfg_accessible-not_sure.rs b/src/test/ui/conditional-compilation/cfg_accessible-not_sure.rs
index d68acd2451fb..99a7949db173 100644
--- a/src/test/ui/conditional-compilation/cfg_accessible-not_sure.rs
+++ b/src/test/ui/conditional-compilation/cfg_accessible-not_sure.rs
@@ -46,7 +46,7 @@ const C: bool = true;
 trait Trait {}
 impl dyn Trait { fn existing() {} }
 
-// FIXME: Should be a error for edition > 2015
+// FIXME: Should be an error for edition > 2015
 #[cfg_accessible(Trait::existing)] //~ ERROR not sure
 const A: bool = true;
 #[cfg_accessible(Trait::unresolved)] //~ ERROR not sure
diff --git a/src/test/ui/const-generics/generic_const_exprs/issue-99705.rs b/src/test/ui/const-generics/generic_const_exprs/issue-99705.rs
new file mode 100644
index 000000000000..75b57b621bb5
--- /dev/null
+++ b/src/test/ui/const-generics/generic_const_exprs/issue-99705.rs
@@ -0,0 +1,33 @@
+// check-pass
+#![crate_type = "lib"]
+#![feature(generic_const_exprs)]
+#![allow(incomplete_features)]
+pub trait MyIterator {
+    type Output;
+}
+
+pub trait Foo {
+    const ABC: usize;
+}
+
+pub struct IteratorStruct<const N: usize>{
+
+}
+
+pub struct Bar<const N: usize> {
+    pub data: [usize; N]
+}
+
+impl<const N: usize> MyIterator for IteratorStruct<N> {
+    type Output = Bar<N>;
+}
+
+pub fn test1<T: Foo>() -> impl MyIterator<Output = Bar<{T::ABC}>> where [(); T::ABC]: Sized {
+    IteratorStruct::<{T::ABC}>{}
+}
+
+pub trait Baz<const N: usize>{}
+impl<const N: usize> Baz<N> for Bar<N> {}
+pub fn test2<T: Foo>() -> impl MyIterator<Output = impl Baz<{ T::ABC }>> where [(); T::ABC]: Sized {
+    IteratorStruct::<{T::ABC}>{}
+}
diff --git a/src/test/ui/const-generics/issues/issue-82956.stderr b/src/test/ui/const-generics/issues/issue-82956.stderr
index c8b999da9810..d2320293e857 100644
--- a/src/test/ui/const-generics/issues/issue-82956.stderr
+++ b/src/test/ui/const-generics/issues/issue-82956.stderr
@@ -2,7 +2,7 @@ error[E0433]: failed to resolve: use of undeclared type `IntoIter`
   --> $DIR/issue-82956.rs:25:24
    |
 LL |         let mut iter = IntoIter::new(self);
-   |                        ^^^^^^^^ not found in this scope
+   |                        ^^^^^^^^ use of undeclared type `IntoIter`
    |
 help: consider importing one of these items
    |
diff --git a/src/test/ui/const-generics/min_const_generics/macro-fail.rs b/src/test/ui/const-generics/min_const_generics/macro-fail.rs
index f83518fc9d47..7fb69032e6fc 100644
--- a/src/test/ui/const-generics/min_const_generics/macro-fail.rs
+++ b/src/test/ui/const-generics/min_const_generics/macro-fail.rs
@@ -14,7 +14,6 @@ impl<const N: usize> Marker<N> for Example<N> {}
 fn make_marker() -> impl Marker<gimme_a_const!(marker)> {
   //~^ ERROR: type provided when a constant was expected
   Example::<gimme_a_const!(marker)>
-  //~^ ERROR: type provided when a constant was expected
 }
 
 fn from_marker(_: impl Marker<{
@@ -34,9 +33,7 @@ fn main() {
   }>;
 
   let _fail = Example::<external_macro!()>;
-  //~^ ERROR: type provided when a constant was expected
 
   let _fail = Example::<gimme_a_const!()>;
-  //~^ ERROR: type provided when a constant was expected
-  //~| ERROR unexpected end of macro invocation
+  //~^ ERROR unexpected end of macro invocation
 }
diff --git a/src/test/ui/const-generics/min_const_generics/macro-fail.stderr b/src/test/ui/const-generics/min_const_generics/macro-fail.stderr
index d5dd70d9b489..9f73b91aabeb 100644
--- a/src/test/ui/const-generics/min_const_generics/macro-fail.stderr
+++ b/src/test/ui/const-generics/min_const_generics/macro-fail.stderr
@@ -1,5 +1,5 @@
 error: expected type, found `{`
-  --> $DIR/macro-fail.rs:29:27
+  --> $DIR/macro-fail.rs:28:27
    |
 LL | fn make_marker() -> impl Marker<gimme_a_const!(marker)> {
    |                                 ----------------------
@@ -13,7 +13,7 @@ LL |       ($rusty: ident) => {{ let $rusty = 3; *&$rusty }}
    = note: this error originates in the macro `gimme_a_const` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: expected type, found `{`
-  --> $DIR/macro-fail.rs:29:27
+  --> $DIR/macro-fail.rs:28:27
    |
 LL |   Example::<gimme_a_const!(marker)>
    |             ----------------------
@@ -46,13 +46,19 @@ LL |     let _fail = Example::<external_macro!()>;
    = note: this error originates in the macro `external_macro` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: unexpected end of macro invocation
-  --> $DIR/macro-fail.rs:39:25
+  --> $DIR/macro-fail.rs:37:25
    |
 LL |     macro_rules! gimme_a_const {
    |     -------------------------- when calling this macro
 ...
 LL |   let _fail = Example::<gimme_a_const!()>;
    |                         ^^^^^^^^^^^^^^^^ missing tokens in macro arguments
+   |
+note: while trying to match meta-variable `$rusty:ident`
+  --> $DIR/macro-fail.rs:28:8
+   |
+LL |       ($rusty: ident) => {{ let $rusty = 3; *&$rusty }}
+   |        ^^^^^^^^^^^^^
 
 error[E0747]: type provided when a constant was expected
   --> $DIR/macro-fail.rs:14:33
@@ -60,24 +66,6 @@ error[E0747]: type provided when a constant was expected
 LL | fn make_marker() -> impl Marker<gimme_a_const!(marker)> {
    |                                 ^^^^^^^^^^^^^^^^^^^^^^
 
-error[E0747]: type provided when a constant was expected
-  --> $DIR/macro-fail.rs:16:13
-   |
-LL |   Example::<gimme_a_const!(marker)>
-   |             ^^^^^^^^^^^^^^^^^^^^^^
-
-error[E0747]: type provided when a constant was expected
-  --> $DIR/macro-fail.rs:36:25
-   |
-LL |   let _fail = Example::<external_macro!()>;
-   |                         ^^^^^^^^^^^^^^^^^
-
-error[E0747]: type provided when a constant was expected
-  --> $DIR/macro-fail.rs:39:25
-   |
-LL |   let _fail = Example::<gimme_a_const!()>;
-   |                         ^^^^^^^^^^^^^^^^
-
-error: aborting due to 8 previous errors
+error: aborting due to 5 previous errors
 
 For more information about this error, try `rustc --explain E0747`.
diff --git a/src/test/ui/consts/const-eval/const-eval-intrinsic-promotion.stderr b/src/test/ui/consts/const-eval/const-eval-intrinsic-promotion.stderr
index 78143042ece7..ed6a6ee6e0fd 100644
--- a/src/test/ui/consts/const-eval/const-eval-intrinsic-promotion.stderr
+++ b/src/test/ui/consts/const-eval/const-eval-intrinsic-promotion.stderr
@@ -4,7 +4,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     let x: &'static usize =
    |            -------------- type annotation requires that borrow lasts for `'static`
 LL |         &std::intrinsics::size_of::<i32>();
-   |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
 LL | }
    | - temporary value is freed at the end of this statement
 
diff --git a/src/test/ui/consts/const-eval/dont_promote_unstable_const_fn.stderr b/src/test/ui/consts/const-eval/dont_promote_unstable_const_fn.stderr
index 69e3ca716a90..2e697b219c5a 100644
--- a/src/test/ui/consts/const-eval/dont_promote_unstable_const_fn.stderr
+++ b/src/test/ui/consts/const-eval/dont_promote_unstable_const_fn.stderr
@@ -10,7 +10,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/dont_promote_unstable_const_fn.rs:17:28
    |
 LL |     let _: &'static u32 = &foo();
-   |            ------------    ^^^^^ creates a temporary which is freed while still in use
+   |            ------------    ^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 LL | }
@@ -20,7 +20,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/dont_promote_unstable_const_fn.rs:21:28
    |
 LL |     let _: &'static u32 = &meh();
-   |            ------------    ^^^^^ creates a temporary which is freed while still in use
+   |            ------------    ^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -31,7 +31,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/dont_promote_unstable_const_fn.rs:22:26
    |
 LL |     let x: &'static _ = &std::time::Duration::from_millis(42).subsec_millis();
-   |            ----------    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            ----------    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 LL |
diff --git a/src/test/ui/consts/const-eval/dont_promote_unstable_const_fn_cross_crate.stderr b/src/test/ui/consts/const-eval/dont_promote_unstable_const_fn_cross_crate.stderr
index 129f06151074..aa742d784e03 100644
--- a/src/test/ui/consts/const-eval/dont_promote_unstable_const_fn_cross_crate.stderr
+++ b/src/test/ui/consts/const-eval/dont_promote_unstable_const_fn_cross_crate.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/dont_promote_unstable_const_fn_cross_crate.rs:8:28
    |
 LL |     let _: &'static u32 = &foo();
-   |            ------------    ^^^^^ creates a temporary which is freed while still in use
+   |            ------------    ^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 LL |     let _x: &'static u32 = &foo();
@@ -13,7 +13,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/dont_promote_unstable_const_fn_cross_crate.rs:9:29
    |
 LL |     let _x: &'static u32 = &foo();
-   |             ------------    ^^^^^ creates a temporary which is freed while still in use
+   |             ------------    ^^^^^ creates a temporary value which is freed while still in use
    |             |
    |             type annotation requires that borrow lasts for `'static`
 LL | }
diff --git a/src/test/ui/consts/const-eval/issue-50814.rs b/src/test/ui/consts/const-eval/issue-50814.rs
index 5a587701f787..9c6108292b52 100644
--- a/src/test/ui/consts/const-eval/issue-50814.rs
+++ b/src/test/ui/consts/const-eval/issue-50814.rs
@@ -9,16 +9,16 @@ impl Unsigned for U8 {
     const MAX: u8 = 0xff;
 }
 
-struct Sum<A,B>(A,B);
+struct Sum<A, B>(A, B);
 
-impl<A: Unsigned, B: Unsigned> Unsigned for Sum<A,B> {
+impl<A: Unsigned, B: Unsigned> Unsigned for Sum<A, B> {
     const MAX: u8 = A::MAX + B::MAX;
     //~^ ERROR evaluation of `<Sum<U8, U8> as Unsigned>::MAX` failed
 }
 
 fn foo<T>(_: T) -> &'static u8 {
-    &Sum::<U8,U8>::MAX
-    //~^ ERROR E0080
+    &Sum::<U8, U8>::MAX
+    //~^ ERROR evaluation of `foo::<i32>` failed [E0080]
 }
 
 fn main() {
diff --git a/src/test/ui/consts/const-eval/issue-50814.stderr b/src/test/ui/consts/const-eval/issue-50814.stderr
index 46dd2b89fa2a..38e9dc36ee98 100644
--- a/src/test/ui/consts/const-eval/issue-50814.stderr
+++ b/src/test/ui/consts/const-eval/issue-50814.stderr
@@ -7,8 +7,8 @@ LL |     const MAX: u8 = A::MAX + B::MAX;
 error[E0080]: evaluation of `foo::<i32>` failed
   --> $DIR/issue-50814.rs:20:6
    |
-LL |     &Sum::<U8,U8>::MAX
-   |      ^^^^^^^^^^^^^^^^^ referenced constant has errors
+LL |     &Sum::<U8, U8>::MAX
+   |      ^^^^^^^^^^^^^^^^^^ referenced constant has errors
 
 note: the above error was encountered while instantiating `fn foo::<i32>`
   --> $DIR/issue-50814.rs:25:5
diff --git a/src/test/ui/consts/const-eval/promoted_const_fn_fail.stderr b/src/test/ui/consts/const-eval/promoted_const_fn_fail.stderr
index 596fa090d976..2d4e7c83d3e4 100644
--- a/src/test/ui/consts/const-eval/promoted_const_fn_fail.stderr
+++ b/src/test/ui/consts/const-eval/promoted_const_fn_fail.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promoted_const_fn_fail.rs:17:27
    |
 LL |     let x: &'static u8 = &(bar() + 1);
-   |            -----------    ^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            -----------    ^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
diff --git a/src/test/ui/consts/const-eval/promoted_const_fn_fail_deny_const_err.stderr b/src/test/ui/consts/const-eval/promoted_const_fn_fail_deny_const_err.stderr
index 63dc43a41a8f..9ebae3a18a32 100644
--- a/src/test/ui/consts/const-eval/promoted_const_fn_fail_deny_const_err.stderr
+++ b/src/test/ui/consts/const-eval/promoted_const_fn_fail_deny_const_err.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promoted_const_fn_fail_deny_const_err.rs:18:27
    |
 LL |     let x: &'static u8 = &(bar() + 1);
-   |            -----------    ^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            -----------    ^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
diff --git a/src/test/ui/consts/const-eval/promoted_raw_ptr_ops.stderr b/src/test/ui/consts/const-eval/promoted_raw_ptr_ops.stderr
index 8ac60da38634..01fcf2ec2134 100644
--- a/src/test/ui/consts/const-eval/promoted_raw_ptr_ops.stderr
+++ b/src/test/ui/consts/const-eval/promoted_raw_ptr_ops.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promoted_raw_ptr_ops.rs:2:29
    |
 LL |     let x: &'static bool = &(42 as *const i32 == 43 as *const i32);
-   |            -------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            -------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -13,7 +13,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promoted_raw_ptr_ops.rs:4:30
    |
 LL |     let y: &'static usize = &(&1 as *const i32 as usize + 1);
-   |            --------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            --------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -24,7 +24,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promoted_raw_ptr_ops.rs:6:28
    |
 LL |     let z: &'static i32 = &(unsafe { *(42 as *const i32) });
-   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -35,7 +35,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promoted_raw_ptr_ops.rs:8:29
    |
 LL |     let a: &'static bool = &(main as fn() == main as fn());
-   |            -------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            -------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 LL |
diff --git a/src/test/ui/consts/const-eval/transmute-const-promotion.stderr b/src/test/ui/consts/const-eval/transmute-const-promotion.stderr
index 15b9b56ea660..434a957f6484 100644
--- a/src/test/ui/consts/const-eval/transmute-const-promotion.stderr
+++ b/src/test/ui/consts/const-eval/transmute-const-promotion.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/transmute-const-promotion.rs:4:37
    |
 LL |     let x: &'static u32 = unsafe { &mem::transmute(3.0f32) };
-   |            ------------             ^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            ------------             ^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 LL |
diff --git a/src/test/ui/consts/const-eval/union_promotion.stderr b/src/test/ui/consts/const-eval/union_promotion.stderr
index 70808c520d3f..42f17de20034 100644
--- a/src/test/ui/consts/const-eval/union_promotion.stderr
+++ b/src/test/ui/consts/const-eval/union_promotion.stderr
@@ -7,7 +7,7 @@ LL |       let x: &'static bool = &unsafe {
    | |            type annotation requires that borrow lasts for `'static`
 LL | |         Foo { a: &1 }.b == Foo { a: &2 }.b
 LL | |     };
-   | |_____^ creates a temporary which is freed while still in use
+   | |_____^ creates a temporary value which is freed while still in use
 LL |   }
    |   - temporary value is freed at the end of this statement
 
diff --git a/src/test/ui/consts/const-int-conversion.stderr b/src/test/ui/consts/const-int-conversion.stderr
index 61162a792262..5dd757e3f5ee 100644
--- a/src/test/ui/consts/const-int-conversion.stderr
+++ b/src/test/ui/consts/const-int-conversion.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/const-int-conversion.rs:2:28
    |
 LL |     let x: &'static i32 = &(5_i32.reverse_bits());
-   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -13,7 +13,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/const-int-conversion.rs:4:28
    |
 LL |     let y: &'static i32 = &(i32::from_be_bytes([0x12, 0x34, 0x56, 0x78]));
-   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -24,7 +24,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/const-int-conversion.rs:6:28
    |
 LL |     let z: &'static i32 = &(i32::from_le_bytes([0x12, 0x34, 0x56, 0x78]));
-   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -35,7 +35,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/const-int-conversion.rs:8:28
    |
 LL |     let a: &'static i32 = &(i32::from_be(i32::from_ne_bytes([0x80, 0, 0, 0])));
-   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -46,7 +46,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/const-int-conversion.rs:10:29
    |
 LL |     let b: &'static [u8] = &(0x12_34_56_78_i32.to_be_bytes());
-   |            -------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            -------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -57,7 +57,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/const-int-conversion.rs:12:29
    |
 LL |     let c: &'static [u8] = &(0x12_34_56_78_i32.to_le_bytes());
-   |            -------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            -------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -68,7 +68,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/const-int-conversion.rs:14:29
    |
 LL |     let d: &'static [u8] = &(i32::MIN.to_be().to_ne_bytes());
-   |            -------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            -------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 LL |
diff --git a/src/test/ui/consts/const-int-overflowing.stderr b/src/test/ui/consts/const-int-overflowing.stderr
index 56c7f7f092d6..7d3689e6ec7d 100644
--- a/src/test/ui/consts/const-int-overflowing.stderr
+++ b/src/test/ui/consts/const-int-overflowing.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/const-int-overflowing.rs:2:36
    |
 LL |     let x: &'static (i32, bool) = &(5_i32.overflowing_add(3));
-   |            --------------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            --------------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -13,7 +13,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/const-int-overflowing.rs:4:36
    |
 LL |     let y: &'static (i32, bool) = &(5_i32.overflowing_sub(3));
-   |            --------------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            --------------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -24,7 +24,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/const-int-overflowing.rs:6:36
    |
 LL |     let z: &'static (i32, bool) = &(5_i32.overflowing_mul(3));
-   |            --------------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            --------------------    ^^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 LL |
diff --git a/src/test/ui/consts/const-int-rotate.stderr b/src/test/ui/consts/const-int-rotate.stderr
index ed265804bbc6..039da1c31c57 100644
--- a/src/test/ui/consts/const-int-rotate.stderr
+++ b/src/test/ui/consts/const-int-rotate.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/const-int-rotate.rs:2:28
    |
 LL |     let x: &'static i32 = &(5_i32.rotate_left(3));
-   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -13,7 +13,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/const-int-rotate.rs:4:28
    |
 LL |     let y: &'static i32 = &(5_i32.rotate_right(3));
-   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 LL |
diff --git a/src/test/ui/consts/const-int-sign.stderr b/src/test/ui/consts/const-int-sign.stderr
index 5f8fd4141804..fc23d9d2b294 100644
--- a/src/test/ui/consts/const-int-sign.stderr
+++ b/src/test/ui/consts/const-int-sign.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/const-int-sign.rs:2:29
    |
 LL |     let x: &'static bool = &(5_i32.is_negative());
-   |            -------------    ^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            -------------    ^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -13,7 +13,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/const-int-sign.rs:4:29
    |
 LL |     let y: &'static bool = &(5_i32.is_positive());
-   |            -------------    ^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            -------------    ^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 LL |
diff --git a/src/test/ui/consts/const-int-wrapping.stderr b/src/test/ui/consts/const-int-wrapping.stderr
index 5174b72659cd..1342fadc4055 100644
--- a/src/test/ui/consts/const-int-wrapping.stderr
+++ b/src/test/ui/consts/const-int-wrapping.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/const-int-wrapping.rs:2:28
    |
 LL |     let x: &'static i32 = &(5_i32.wrapping_add(3));
-   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -13,7 +13,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/const-int-wrapping.rs:4:28
    |
 LL |     let y: &'static i32 = &(5_i32.wrapping_sub(3));
-   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -24,7 +24,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/const-int-wrapping.rs:6:28
    |
 LL |     let z: &'static i32 = &(5_i32.wrapping_mul(3));
-   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -35,7 +35,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/const-int-wrapping.rs:8:28
    |
 LL |     let a: &'static i32 = &(5_i32.wrapping_shl(3));
-   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -46,7 +46,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/const-int-wrapping.rs:10:28
    |
 LL |     let b: &'static i32 = &(5_i32.wrapping_shr(3));
-   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            ------------    ^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 LL |
diff --git a/src/test/ui/consts/const-mut-refs/mut_ref_in_final.stderr b/src/test/ui/consts/const-mut-refs/mut_ref_in_final.stderr
index 3a9ce79f10ef..78c58b5ab092 100644
--- a/src/test/ui/consts/const-mut-refs/mut_ref_in_final.stderr
+++ b/src/test/ui/consts/const-mut-refs/mut_ref_in_final.stderr
@@ -11,7 +11,7 @@ LL | const B3: Option<&mut i32> = Some(&mut 42);
    |                              ----------^^-
    |                              |         | |
    |                              |         | temporary value is freed at the end of this statement
-   |                              |         creates a temporary which is freed while still in use
+   |                              |         creates a temporary value which is freed while still in use
    |                              using this value as a constant requires that borrow lasts for `'static`
 
 error[E0716]: temporary value dropped while borrowed
@@ -21,7 +21,7 @@ LL | const B4: Option<&mut i32> = helper(&mut 42);
    |                              ------------^^-
    |                              |           | |
    |                              |           | temporary value is freed at the end of this statement
-   |                              |           creates a temporary which is freed while still in use
+   |                              |           creates a temporary value which is freed while still in use
    |                              using this value as a constant requires that borrow lasts for `'static`
 
 error[E0716]: temporary value dropped while borrowed
@@ -31,7 +31,7 @@ LL | const FOO: NotAMutex<&mut i32> = NotAMutex(UnsafeCell::new(&mut 42));
    |                                  -------------------------------^^--
    |                                  |                              |  |
    |                                  |                              |  temporary value is freed at the end of this statement
-   |                                  |                              creates a temporary which is freed while still in use
+   |                                  |                              creates a temporary value which is freed while still in use
    |                                  using this value as a constant requires that borrow lasts for `'static`
 
 error[E0716]: temporary value dropped while borrowed
@@ -41,7 +41,7 @@ LL | static FOO2: NotAMutex<&mut i32> = NotAMutex(UnsafeCell::new(&mut 42));
    |                                    -------------------------------^^--
    |                                    |                              |  |
    |                                    |                              |  temporary value is freed at the end of this statement
-   |                                    |                              creates a temporary which is freed while still in use
+   |                                    |                              creates a temporary value which is freed while still in use
    |                                    using this value as a static requires that borrow lasts for `'static`
 
 error[E0716]: temporary value dropped while borrowed
@@ -51,7 +51,7 @@ LL | static mut FOO3: NotAMutex<&mut i32> = NotAMutex(UnsafeCell::new(&mut 42));
    |                                        -------------------------------^^--
    |                                        |                              |  |
    |                                        |                              |  temporary value is freed at the end of this statement
-   |                                        |                              creates a temporary which is freed while still in use
+   |                                        |                              creates a temporary value which is freed while still in use
    |                                        using this value as a static requires that borrow lasts for `'static`
 
 error: aborting due to 6 previous errors
diff --git a/src/test/ui/consts/const-ptr-nonnull.stderr b/src/test/ui/consts/const-ptr-nonnull.stderr
index 26946fb99024..dbcb0c86052e 100644
--- a/src/test/ui/consts/const-ptr-nonnull.stderr
+++ b/src/test/ui/consts/const-ptr-nonnull.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/const-ptr-nonnull.rs:4:37
    |
 LL |     let x: &'static NonNull<u32> = &(NonNull::dangling());
-   |            ---------------------    ^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            ---------------------    ^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -13,7 +13,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/const-ptr-nonnull.rs:9:37
    |
 LL |     let x: &'static NonNull<u32> = &(non_null.cast());
-   |            ---------------------    ^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            ---------------------    ^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 LL |
diff --git a/src/test/ui/consts/const-ptr-unique.stderr b/src/test/ui/consts/const-ptr-unique.stderr
index 3644cf4cec7d..83448c3e8d87 100644
--- a/src/test/ui/consts/const-ptr-unique.stderr
+++ b/src/test/ui/consts/const-ptr-unique.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/const-ptr-unique.rs:8:33
    |
 LL |     let x: &'static *mut u32 = &(unique.as_ptr());
-   |            -----------------    ^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |            -----------------    ^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 LL |
diff --git a/src/test/ui/consts/control-flow/interior-mutability.stderr b/src/test/ui/consts/control-flow/interior-mutability.stderr
index 4f9c7d34c35f..db2ffb91b988 100644
--- a/src/test/ui/consts/control-flow/interior-mutability.stderr
+++ b/src/test/ui/consts/control-flow/interior-mutability.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/interior-mutability.rs:40:26
    |
 LL |     let x: &'static _ = &X;
-   |            ----------    ^ creates a temporary which is freed while still in use
+   |            ----------    ^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -13,7 +13,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/interior-mutability.rs:41:26
    |
 LL |     let y: &'static _ = &Y;
-   |            ----------    ^ creates a temporary which is freed while still in use
+   |            ----------    ^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 LL |     let z: &'static _ = &Z;
@@ -24,7 +24,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/interior-mutability.rs:42:26
    |
 LL |     let z: &'static _ = &Z;
-   |            ----------    ^ creates a temporary which is freed while still in use
+   |            ----------    ^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 LL | }
diff --git a/src/test/ui/consts/fn_trait_refs.rs b/src/test/ui/consts/fn_trait_refs.rs
new file mode 100644
index 000000000000..b507492970ab
--- /dev/null
+++ b/src/test/ui/consts/fn_trait_refs.rs
@@ -0,0 +1,77 @@
+// check-pass
+
+#![feature(const_fn_trait_ref_impls)]
+#![feature(fn_traits)]
+#![feature(unboxed_closures)]
+#![feature(const_trait_impl)]
+#![feature(const_mut_refs)]
+#![feature(const_cmp)]
+#![feature(const_refs_to_cell)]
+
+use std::marker::Destruct;
+
+const fn tester_fn<T>(f: T) -> T::Output
+where
+    T: ~const Fn<()> + ~const Destruct,
+{
+    f()
+}
+
+const fn tester_fn_mut<T>(mut f: T) -> T::Output
+where
+    T: ~const FnMut<()> + ~const Destruct,
+{
+    f()
+}
+
+const fn tester_fn_once<T>(f: T) -> T::Output
+where
+    T: ~const FnOnce<()>,
+{
+    f()
+}
+
+const fn test_fn<T>(mut f: T) -> (T::Output, T::Output, T::Output)
+where
+    T: ~const Fn<()> + ~const Destruct,
+{
+    (
+        // impl<A: Tuple, F: ~const Fn + ?Sized> const Fn<A> for &F
+        tester_fn(&f),
+        // impl<A: Tuple, F: ~const Fn + ?Sized> const FnMut<A> for &F
+        tester_fn_mut(&f),
+        // impl<A: Tuple, F: ~const Fn + ?Sized> const FnOnce<A> for &F
+        tester_fn_once(&f),
+    )
+}
+
+const fn test_fn_mut<T>(mut f: T) -> (T::Output, T::Output)
+where
+    T: ~const FnMut<()> + ~const Destruct,
+{
+    (
+        // impl<A: Tuple, F: ~const FnMut + ?Sized> const FnMut<A> for &mut F
+        tester_fn_mut(&mut f),
+        // impl<A: Tuple, F: ~const FnMut + ?Sized> const FnOnce<A> for &mut F
+        tester_fn_once(&mut f),
+    )
+}
+const fn test(i: i32) -> i32 {
+    i + 1
+}
+
+fn main() {
+    const fn one() -> i32 {
+        1
+    };
+    const fn two() -> i32 {
+        2
+    };
+    const _: () = {
+        let test_one = test_fn(one);
+        assert!(test_one == (1, 1, 1));
+
+        let test_two = test_fn_mut(two);
+        assert!(test_two == (2, 2));
+    };
+}
diff --git a/src/test/ui/consts/invalid-const-in-body.rs b/src/test/ui/consts/invalid-const-in-body.rs
new file mode 100644
index 000000000000..f0fa3bb7bd13
--- /dev/null
+++ b/src/test/ui/consts/invalid-const-in-body.rs
@@ -0,0 +1,6 @@
+fn f() -> impl Sized {
+    2.0E
+    //~^ ERROR expected at least one digit in exponent
+}
+
+fn main() {}
diff --git a/src/test/ui/consts/invalid-const-in-body.stderr b/src/test/ui/consts/invalid-const-in-body.stderr
new file mode 100644
index 000000000000..3be658359461
--- /dev/null
+++ b/src/test/ui/consts/invalid-const-in-body.stderr
@@ -0,0 +1,8 @@
+error: expected at least one digit in exponent
+  --> $DIR/invalid-const-in-body.rs:2:5
+   |
+LL |     2.0E
+   |     ^^^^
+
+error: aborting due to previous error
+
diff --git a/src/test/ui/consts/invalid-inline-const-in-match-arm.rs b/src/test/ui/consts/invalid-inline-const-in-match-arm.rs
new file mode 100644
index 000000000000..4d2d8fb1303c
--- /dev/null
+++ b/src/test/ui/consts/invalid-inline-const-in-match-arm.rs
@@ -0,0 +1,9 @@
+#![allow(incomplete_features)]
+#![feature(inline_const_pat)]
+
+fn main() {
+    match () {
+        const { (|| {})() } => {}
+        //~^ ERROR cannot call non-const closure in constants
+    }
+}
diff --git a/src/test/ui/consts/invalid-inline-const-in-match-arm.stderr b/src/test/ui/consts/invalid-inline-const-in-match-arm.stderr
new file mode 100644
index 000000000000..ab594c921f91
--- /dev/null
+++ b/src/test/ui/consts/invalid-inline-const-in-match-arm.stderr
@@ -0,0 +1,12 @@
+error[E0015]: cannot call non-const closure in constants
+  --> $DIR/invalid-inline-const-in-match-arm.rs:6:17
+   |
+LL |         const { (|| {})() } => {}
+   |                 ^^^^^^^^^
+   |
+   = note: closures need an RFC before allowed to be called in constants
+   = note: calls in constants are limited to constant functions, tuple structs and tuple variants
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0015`.
diff --git a/src/test/ui/consts/issue-102117.rs b/src/test/ui/consts/issue-102117.rs
index b77342c4135e..3ed90aed2350 100644
--- a/src/test/ui/consts/issue-102117.rs
+++ b/src/test/ui/consts/issue-102117.rs
@@ -14,11 +14,11 @@ pub struct VTable {
 impl VTable {
     pub fn new<T>() -> &'static Self {
         const {
-          //~^ ERROR the parameter type `T` may not live long enough
-          //~| ERROR the parameter type `T` may not live long enough
             &VTable {
                 layout: Layout::new::<T>(),
                 type_id: TypeId::of::<T>(),
+                //~^ ERROR the parameter type `T` may not live long enough
+                //~| ERROR the parameter type `T` may not live long enough
                 drop_in_place: unsafe {
                     transmute::<unsafe fn(*mut T), unsafe fn(*mut ())>(drop_in_place::<T>)
                 },
diff --git a/src/test/ui/consts/issue-102117.stderr b/src/test/ui/consts/issue-102117.stderr
index eb4b329bd813..f42bcf90fb75 100644
--- a/src/test/ui/consts/issue-102117.stderr
+++ b/src/test/ui/consts/issue-102117.stderr
@@ -1,14 +1,8 @@
 error[E0310]: the parameter type `T` may not live long enough
-  --> $DIR/issue-102117.rs:16:9
+  --> $DIR/issue-102117.rs:19:26
    |
-LL | /         const {
-LL | |
-LL | |
-LL | |             &VTable {
-...  |
-LL | |             }
-LL | |         }
-   | |_________^ ...so that the type `T` will meet its required lifetime bounds
+LL |                 type_id: TypeId::of::<T>(),
+   |                          ^^^^^^^^^^^^^^^^^ ...so that the type `T` will meet its required lifetime bounds
    |
 help: consider adding an explicit lifetime bound...
    |
@@ -16,16 +10,10 @@ LL |     pub fn new<T: 'static>() -> &'static Self {
    |                 +++++++++
 
 error[E0310]: the parameter type `T` may not live long enough
-  --> $DIR/issue-102117.rs:16:9
+  --> $DIR/issue-102117.rs:19:26
    |
-LL | /         const {
-LL | |
-LL | |
-LL | |             &VTable {
-...  |
-LL | |             }
-LL | |         }
-   | |_________^ ...so that the type `T` will meet its required lifetime bounds
+LL |                 type_id: TypeId::of::<T>(),
+   |                          ^^^^^^^^^^^^^^^^^ ...so that the type `T` will meet its required lifetime bounds
    |
 help: consider adding an explicit lifetime bound...
    |
diff --git a/src/test/ui/consts/issue-103790.rs b/src/test/ui/consts/issue-103790.rs
new file mode 100644
index 000000000000..ea3cac605b15
--- /dev/null
+++ b/src/test/ui/consts/issue-103790.rs
@@ -0,0 +1,10 @@
+#![feature(generic_const_exprs)]
+#![allow(incomplete_features)]
+
+struct S<const S: (), const S: S = { S }>;
+//~^ ERROR the name `S` is already used for a generic parameter in this item's generic parameters
+//~| ERROR missing generics for struct `S`
+//~| ERROR cycle detected when computing type of `S::S`
+//~| ERROR cycle detected when computing type of `S`
+
+fn main() {}
diff --git a/src/test/ui/consts/issue-103790.stderr b/src/test/ui/consts/issue-103790.stderr
new file mode 100644
index 000000000000..41b0816dc32a
--- /dev/null
+++ b/src/test/ui/consts/issue-103790.stderr
@@ -0,0 +1,65 @@
+error[E0403]: the name `S` is already used for a generic parameter in this item's generic parameters
+  --> $DIR/issue-103790.rs:4:29
+   |
+LL | struct S<const S: (), const S: S = { S }>;
+   |                -            ^ already used
+   |                |
+   |                first use of `S`
+
+error[E0107]: missing generics for struct `S`
+  --> $DIR/issue-103790.rs:4:32
+   |
+LL | struct S<const S: (), const S: S = { S }>;
+   |                                ^ expected at least 1 generic argument
+   |
+note: struct defined here, with at least 1 generic parameter: `S`
+  --> $DIR/issue-103790.rs:4:8
+   |
+LL | struct S<const S: (), const S: S = { S }>;
+   |        ^ -----------
+help: add missing generic argument
+   |
+LL | struct S<const S: (), const S: S<S> = { S }>;
+   |                                ~~~~
+
+error[E0391]: cycle detected when computing type of `S::S`
+  --> $DIR/issue-103790.rs:4:32
+   |
+LL | struct S<const S: (), const S: S = { S }>;
+   |                                ^
+   |
+   = note: ...which immediately requires computing type of `S::S` again
+note: cycle used when computing type of `S`
+  --> $DIR/issue-103790.rs:4:1
+   |
+LL | struct S<const S: (), const S: S = { S }>;
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error[E0391]: cycle detected when computing type of `S`
+  --> $DIR/issue-103790.rs:4:1
+   |
+LL | struct S<const S: (), const S: S = { S }>;
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+note: ...which requires computing type of `S::S`...
+  --> $DIR/issue-103790.rs:4:32
+   |
+LL | struct S<const S: (), const S: S = { S }>;
+   |                                ^
+   = note: ...which again requires computing type of `S`, completing the cycle
+note: cycle used when collecting item types in top-level module
+  --> $DIR/issue-103790.rs:1:1
+   |
+LL | / #![feature(generic_const_exprs)]
+LL | | #![allow(incomplete_features)]
+LL | |
+LL | | struct S<const S: (), const S: S = { S }>;
+...  |
+LL | |
+LL | | fn main() {}
+   | |____________^
+
+error: aborting due to 4 previous errors
+
+Some errors have detailed explanations: E0107, E0391, E0403.
+For more information about an error, try `rustc --explain E0107`.
diff --git a/src/test/ui/consts/issue-104155.rs b/src/test/ui/consts/issue-104155.rs
new file mode 100644
index 000000000000..1cc8f81b0d25
--- /dev/null
+++ b/src/test/ui/consts/issue-104155.rs
@@ -0,0 +1,5 @@
+// check-pass
+const _: () = core::mem::forget(Box::<u32>::default);
+const _: () = core::mem::forget(|| Box::<u32>::default());
+
+fn main() {}
diff --git a/src/test/ui/consts/issue-54224.stderr b/src/test/ui/consts/issue-54224.stderr
index 8dcb4daca3b7..55fe55759df5 100644
--- a/src/test/ui/consts/issue-54224.stderr
+++ b/src/test/ui/consts/issue-54224.stderr
@@ -5,7 +5,7 @@ LL | const FOO: Option<&[[u8; 3]]> = Some(&[*b"foo"]);
    |                                 ------^^^^^^^^^-
    |                                 |     |        |
    |                                 |     |        temporary value is freed at the end of this statement
-   |                                 |     creates a temporary which is freed while still in use
+   |                                 |     creates a temporary value which is freed while still in use
    |                                 using this value as a constant requires that borrow lasts for `'static`
 
 error[E0716]: temporary value dropped while borrowed
@@ -15,7 +15,7 @@ LL | pub const Z: Cow<'static, [ [u8; 3] ]> = Cow::Borrowed(&[*b"ABC"]);
    |                                          ---------------^^^^^^^^^-
    |                                          |              |        |
    |                                          |              |        temporary value is freed at the end of this statement
-   |                                          |              creates a temporary which is freed while still in use
+   |                                          |              creates a temporary value which is freed while still in use
    |                                          using this value as a constant requires that borrow lasts for `'static`
 
 error: aborting due to 2 previous errors
diff --git a/src/test/ui/issues/issue-54954.rs b/src/test/ui/consts/issue-54954.rs
similarity index 100%
rename from src/test/ui/issues/issue-54954.rs
rename to src/test/ui/consts/issue-54954.rs
diff --git a/src/test/ui/issues/issue-54954.stderr b/src/test/ui/consts/issue-54954.stderr
similarity index 100%
rename from src/test/ui/issues/issue-54954.stderr
rename to src/test/ui/consts/issue-54954.stderr
diff --git a/src/test/ui/consts/min_const_fn/promotion.stderr b/src/test/ui/consts/min_const_fn/promotion.stderr
index 550423c2d933..0b8dc0ce0e90 100644
--- a/src/test/ui/consts/min_const_fn/promotion.stderr
+++ b/src/test/ui/consts/min_const_fn/promotion.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promotion.rs:11:27
    |
 LL |     let x: &'static () = &foo1();
-   |            -----------    ^^^^^^ creates a temporary which is freed while still in use
+   |            -----------    ^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -13,7 +13,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promotion.rs:12:28
    |
 LL |     let y: &'static i32 = &foo2(42);
-   |            ------------    ^^^^^^^^ creates a temporary which is freed while still in use
+   |            ------------    ^^^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -24,7 +24,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promotion.rs:13:28
    |
 LL |     let z: &'static i32 = &foo3();
-   |            ------------    ^^^^^^ creates a temporary which is freed while still in use
+   |            ------------    ^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -35,7 +35,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promotion.rs:14:34
    |
 LL |     let a: &'static Cell<i32> = &foo4();
-   |            ------------------    ^^^^^^ creates a temporary which is freed while still in use
+   |            ------------------    ^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -46,7 +46,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promotion.rs:15:42
    |
 LL |     let a: &'static Option<Cell<i32>> = &foo5();
-   |            --------------------------    ^^^^^^ creates a temporary which is freed while still in use
+   |            --------------------------    ^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 LL |     let a: &'static Option<Cell<i32>> = &foo6();
@@ -57,7 +57,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promotion.rs:16:42
    |
 LL |     let a: &'static Option<Cell<i32>> = &foo6();
-   |            --------------------------    ^^^^^^ creates a temporary which is freed while still in use
+   |            --------------------------    ^^^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 LL | }
diff --git a/src/test/ui/consts/promote-not.stderr b/src/test/ui/consts/promote-not.stderr
index 0d0b0f9c689b..b93358e8dcce 100644
--- a/src/test/ui/consts/promote-not.stderr
+++ b/src/test/ui/consts/promote-not.stderr
@@ -5,14 +5,14 @@ LL | static mut TEST1: Option<&mut [i32]> = Some(&mut [1, 2, 3]);
    |                                        ----------^^^^^^^^^-
    |                                        |         |        |
    |                                        |         |        temporary value is freed at the end of this statement
-   |                                        |         creates a temporary which is freed while still in use
+   |                                        |         creates a temporary value which is freed while still in use
    |                                        using this value as a static requires that borrow lasts for `'static`
 
 error[E0716]: temporary value dropped while borrowed
   --> $DIR/promote-not.rs:11:18
    |
 LL |     let x = &mut [1,2,3];
-   |                  ^^^^^^^ creates a temporary which is freed while still in use
+   |                  ^^^^^^^ creates a temporary value which is freed while still in use
 LL |     x
    |     - using this value as a static requires that borrow lasts for `'static`
 LL | };
@@ -22,7 +22,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promote-not.rs:20:32
    |
 LL |         let _x: &'static () = &foo();
-   |                 -----------    ^^^^^ creates a temporary which is freed while still in use
+   |                 -----------    ^^^^^ creates a temporary value which is freed while still in use
    |                 |
    |                 type annotation requires that borrow lasts for `'static`
 LL |     }
@@ -32,7 +32,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promote-not.rs:28:29
    |
 LL |     let _x: &'static i32 = &unsafe { U { x: 0 }.x };
-   |             ------------    ^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |             ------------    ^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |             |
    |             type annotation requires that borrow lasts for `'static`
 LL | }
@@ -42,7 +42,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promote-not.rs:33:29
    |
 LL |     let _x: &'static i32 = &unsafe { U { x: 0 }.x };
-   |             ------------    ^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |             ------------    ^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |             |
    |             type annotation requires that borrow lasts for `'static`
 LL | };
@@ -52,7 +52,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promote-not.rs:39:29
    |
 LL |     let _val: &'static _ = &(Cell::new(1), 2).1;
-   |               ----------    ^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |               ----------    ^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |               |
    |               type annotation requires that borrow lasts for `'static`
 LL | };
@@ -62,7 +62,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promote-not.rs:46:29
    |
 LL |     let _val: &'static _ = &(Cell::new(1), 2).0;
-   |               ----------    ^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |               ----------    ^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |               |
    |               type annotation requires that borrow lasts for `'static`
 ...
@@ -73,7 +73,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promote-not.rs:47:29
    |
 LL |     let _val: &'static _ = &(Cell::new(1), 2).1;
-   |               ----------    ^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |               ----------    ^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |               |
    |               type annotation requires that borrow lasts for `'static`
 ...
@@ -84,7 +84,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promote-not.rs:50:29
    |
 LL |     let _val: &'static _ = &(1/0);
-   |               ----------    ^^^^^ creates a temporary which is freed while still in use
+   |               ----------    ^^^^^ creates a temporary value which is freed while still in use
    |               |
    |               type annotation requires that borrow lasts for `'static`
 ...
@@ -95,7 +95,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promote-not.rs:51:29
    |
 LL |     let _val: &'static _ = &(1/(1-1));
-   |               ----------    ^^^^^^^^^ creates a temporary which is freed while still in use
+   |               ----------    ^^^^^^^^^ creates a temporary value which is freed while still in use
    |               |
    |               type annotation requires that borrow lasts for `'static`
 ...
@@ -106,7 +106,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promote-not.rs:52:29
    |
 LL |     let _val: &'static _ = &(1%0);
-   |               ----------    ^^^^^ creates a temporary which is freed while still in use
+   |               ----------    ^^^^^ creates a temporary value which is freed while still in use
    |               |
    |               type annotation requires that borrow lasts for `'static`
 ...
@@ -117,7 +117,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promote-not.rs:53:29
    |
 LL |     let _val: &'static _ = &(1%(1-1));
-   |               ----------    ^^^^^^^^^ creates a temporary which is freed while still in use
+   |               ----------    ^^^^^^^^^ creates a temporary value which is freed while still in use
    |               |
    |               type annotation requires that borrow lasts for `'static`
 ...
@@ -128,7 +128,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promote-not.rs:54:29
    |
 LL |     let _val: &'static _ = &([1,2,3][4]+1);
-   |               ----------    ^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |               ----------    ^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |               |
    |               type annotation requires that borrow lasts for `'static`
 ...
@@ -139,7 +139,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promote-not.rs:57:29
    |
 LL |     let _val: &'static _ = &TEST_DROP;
-   |               ----------    ^^^^^^^^^ creates a temporary which is freed while still in use
+   |               ----------    ^^^^^^^^^ creates a temporary value which is freed while still in use
    |               |
    |               type annotation requires that borrow lasts for `'static`
 ...
@@ -150,7 +150,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promote-not.rs:59:29
    |
 LL |     let _val: &'static _ = &&TEST_DROP;
-   |               ----------    ^^^^^^^^^^ creates a temporary which is freed while still in use
+   |               ----------    ^^^^^^^^^^ creates a temporary value which is freed while still in use
    |               |
    |               type annotation requires that borrow lasts for `'static`
 ...
@@ -161,7 +161,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promote-not.rs:59:30
    |
 LL |     let _val: &'static _ = &&TEST_DROP;
-   |               ----------     ^^^^^^^^^ creates a temporary which is freed while still in use
+   |               ----------     ^^^^^^^^^ creates a temporary value which is freed while still in use
    |               |
    |               type annotation requires that borrow lasts for `'static`
 ...
@@ -172,7 +172,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promote-not.rs:62:29
    |
 LL |     let _val: &'static _ = &(&TEST_DROP,);
-   |               ----------    ^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |               ----------    ^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |               |
    |               type annotation requires that borrow lasts for `'static`
 ...
@@ -183,7 +183,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promote-not.rs:62:31
    |
 LL |     let _val: &'static _ = &(&TEST_DROP,);
-   |               ----------      ^^^^^^^^^ creates a temporary which is freed while still in use
+   |               ----------      ^^^^^^^^^ creates a temporary value which is freed while still in use
    |               |
    |               type annotation requires that borrow lasts for `'static`
 ...
@@ -194,7 +194,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promote-not.rs:65:29
    |
 LL |     let _val: &'static _ = &[&TEST_DROP; 1];
-   |               ----------    ^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |               ----------    ^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
    |               |
    |               type annotation requires that borrow lasts for `'static`
 ...
@@ -207,7 +207,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     let _val: &'static _ = &[&TEST_DROP; 1];
    |               ----------      ^^^^^^^^^    - temporary value is freed at the end of this statement
    |               |               |
-   |               |               creates a temporary which is freed while still in use
+   |               |               creates a temporary value which is freed while still in use
    |               type annotation requires that borrow lasts for `'static`
 
 error: aborting due to 20 previous errors
diff --git a/src/test/ui/consts/promote_const_let.stderr b/src/test/ui/consts/promote_const_let.stderr
index c47d297c9040..975a235a6495 100644
--- a/src/test/ui/consts/promote_const_let.stderr
+++ b/src/test/ui/consts/promote_const_let.stderr
@@ -19,7 +19,7 @@ LL |       let x: &'static u32 = &{
 LL | |         let y = 42;
 LL | |         y
 LL | |     };
-   | |_____^ creates a temporary which is freed while still in use
+   | |_____^ creates a temporary value which is freed while still in use
 LL |   }
    |   - temporary value is freed at the end of this statement
 
diff --git a/src/test/ui/consts/promoted-const-drop.stderr b/src/test/ui/consts/promoted-const-drop.stderr
index 184ba0ea3b37..4802834173fc 100644
--- a/src/test/ui/consts/promoted-const-drop.stderr
+++ b/src/test/ui/consts/promoted-const-drop.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promoted-const-drop.rs:13:26
    |
 LL |     let _: &'static A = &A();
-   |            ----------    ^^^ creates a temporary which is freed while still in use
+   |            ----------    ^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 LL |     let _: &'static [A] = &[C];
@@ -13,7 +13,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/promoted-const-drop.rs:14:28
    |
 LL |     let _: &'static [A] = &[C];
-   |            ------------    ^^^ creates a temporary which is freed while still in use
+   |            ------------    ^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 LL | }
diff --git a/src/test/ui/consts/qualif-union.stderr b/src/test/ui/consts/qualif-union.stderr
index 8ec68ada048a..d847cf88f505 100644
--- a/src/test/ui/consts/qualif-union.stderr
+++ b/src/test/ui/consts/qualif-union.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/qualif-union.rs:28:26
    |
 LL |     let _: &'static _ = &C1;
-   |            ----------    ^^ creates a temporary which is freed while still in use
+   |            ----------    ^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -13,7 +13,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/qualif-union.rs:29:26
    |
 LL |     let _: &'static _ = &C2;
-   |            ----------    ^^ creates a temporary which is freed while still in use
+   |            ----------    ^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -24,7 +24,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/qualif-union.rs:30:26
    |
 LL |     let _: &'static _ = &C3;
-   |            ----------    ^^ creates a temporary which is freed while still in use
+   |            ----------    ^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 ...
@@ -35,7 +35,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/qualif-union.rs:31:26
    |
 LL |     let _: &'static _ = &C4;
-   |            ----------    ^^ creates a temporary which is freed while still in use
+   |            ----------    ^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 LL |     let _: &'static _ = &C5;
@@ -46,7 +46,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/qualif-union.rs:32:26
    |
 LL |     let _: &'static _ = &C5;
-   |            ----------    ^^ creates a temporary which is freed while still in use
+   |            ----------    ^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'static`
 LL | }
diff --git a/src/test/ui/consts/unnormalized-param-env.rs b/src/test/ui/consts/unnormalized-param-env.rs
new file mode 100644
index 000000000000..a7bbe4db9929
--- /dev/null
+++ b/src/test/ui/consts/unnormalized-param-env.rs
@@ -0,0 +1,31 @@
+// check-pass
+
+pub trait CSpace<const N: usize> {
+    type Traj;
+}
+
+pub struct Const<const R: usize>;
+
+pub trait Obstacle<CS, const N: usize> {
+    fn trajectory_free<FT, S1>(&self, t: &FT)
+    where
+        CS::Traj: Sized,
+        CS: CSpace<N>;
+}
+
+// -----
+
+const N: usize = 4;
+
+struct ObstacleSpace2df32;
+
+impl<CS> Obstacle<CS, N> for ObstacleSpace2df32 {
+    fn trajectory_free<TF, S1>(&self, t: &TF)
+    where
+        CS::Traj: Sized,
+        CS: CSpace<N>,
+    {
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/derived-errors/issue-31997-1.stderr b/src/test/ui/derived-errors/issue-31997-1.stderr
index 6d177666ed0f..2f4aabf84531 100644
--- a/src/test/ui/derived-errors/issue-31997-1.stderr
+++ b/src/test/ui/derived-errors/issue-31997-1.stderr
@@ -2,7 +2,7 @@ error[E0433]: failed to resolve: use of undeclared type `HashMap`
   --> $DIR/issue-31997-1.rs:20:19
    |
 LL |     let mut map = HashMap::new();
-   |                   ^^^^^^^ not found in this scope
+   |                   ^^^^^^^ use of undeclared type `HashMap`
    |
 help: consider importing this struct
    |
diff --git a/src/test/ui/derives/clone-debug-dead-code-in-the-same-struct.rs b/src/test/ui/derives/clone-debug-dead-code-in-the-same-struct.rs
index 15d06817577e..6ab1fb7b039b 100644
--- a/src/test/ui/derives/clone-debug-dead-code-in-the-same-struct.rs
+++ b/src/test/ui/derives/clone-debug-dead-code-in-the-same-struct.rs
@@ -3,7 +3,7 @@
 #[derive(Debug)]
 pub struct Whatever {
     pub field0: (),
-    field1: (), //~ ERROR fields `field1`, `field2`, `field3` and `field4` are never read
+    field1: (), //~ ERROR fields `field1`, `field2`, `field3`, and `field4` are never read
     field2: (),
     field3: (),
     field4: (),
diff --git a/src/test/ui/derives/clone-debug-dead-code-in-the-same-struct.stderr b/src/test/ui/derives/clone-debug-dead-code-in-the-same-struct.stderr
index 512b870fa4b6..7f4f78cebc91 100644
--- a/src/test/ui/derives/clone-debug-dead-code-in-the-same-struct.stderr
+++ b/src/test/ui/derives/clone-debug-dead-code-in-the-same-struct.stderr
@@ -1,4 +1,4 @@
-error: fields `field1`, `field2`, `field3` and `field4` are never read
+error: fields `field1`, `field2`, `field3`, and `field4` are never read
   --> $DIR/clone-debug-dead-code-in-the-same-struct.rs:6:5
    |
 LL | pub struct Whatever {
diff --git a/src/test/ui/did_you_mean/issue-103909.rs b/src/test/ui/did_you_mean/issue-103909.rs
new file mode 100644
index 000000000000..20b67cd102d7
--- /dev/null
+++ b/src/test/ui/did_you_mean/issue-103909.rs
@@ -0,0 +1,9 @@
+#![allow(unused_variables)]
+use std::fs::File;
+
+fn main() {
+    if Err(err) = File::open("hello.txt") {
+        //~^ ERROR: cannot find value `err` in this scope
+        //~| ERROR: mismatched types
+    }
+}
diff --git a/src/test/ui/did_you_mean/issue-103909.stderr b/src/test/ui/did_you_mean/issue-103909.stderr
new file mode 100644
index 000000000000..8641017470ba
--- /dev/null
+++ b/src/test/ui/did_you_mean/issue-103909.stderr
@@ -0,0 +1,26 @@
+error[E0425]: cannot find value `err` in this scope
+  --> $DIR/issue-103909.rs:5:12
+   |
+LL |     if Err(err) = File::open("hello.txt") {
+   |            ^^^ not found in this scope
+   |
+help: you might have meant to use pattern matching
+   |
+LL |     if let Err(err) = File::open("hello.txt") {
+   |        +++
+
+error[E0308]: mismatched types
+  --> $DIR/issue-103909.rs:5:8
+   |
+LL |     if Err(err) = File::open("hello.txt") {
+   |        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `bool`, found `()`
+   |
+help: consider adding `let`
+   |
+LL |     if let Err(err) = File::open("hello.txt") {
+   |        +++
+
+error: aborting due to 2 previous errors
+
+Some errors have detailed explanations: E0308, E0425.
+For more information about an error, try `rustc --explain E0308`.
diff --git a/src/test/ui/dropck/dropck-eyepatch-implies-unsafe-impl.stderr b/src/test/ui/dropck/dropck-eyepatch-implies-unsafe-impl.stderr
index 49e55be1b49e..82169ee01bed 100644
--- a/src/test/ui/dropck/dropck-eyepatch-implies-unsafe-impl.stderr
+++ b/src/test/ui/dropck/dropck-eyepatch-implies-unsafe-impl.stderr
@@ -8,6 +8,12 @@ LL | |     // (unsafe to access self.1  due to #[may_dangle] on A)
 LL | |     fn drop(&mut self) { println!("drop {} {:?}", self.0, self.2); }
 LL | | }
    | |_^
+   |
+   = note: the trait `Drop` enforces invariants that the compiler can't check. Review the trait documentation and make sure this implementation upholds those invariants before adding the `unsafe` keyword
+help: add `unsafe` to this trait implementation
+   |
+LL | unsafe impl<#[may_dangle] A, B: fmt::Debug> Drop for Pt<A, B> {
+   | ++++++
 
 error[E0569]: requires an `unsafe impl` declaration due to `#[may_dangle]` attribute
   --> $DIR/dropck-eyepatch-implies-unsafe-impl.rs:27:1
@@ -19,6 +25,12 @@ LL | |     // (unsafe to access self.1 due to #[may_dangle] on 'a)
 LL | |     fn drop(&mut self) { println!("drop {} {:?}", self.0, self.2); }
 LL | | }
    | |_^
+   |
+   = note: the trait `Drop` enforces invariants that the compiler can't check. Review the trait documentation and make sure this implementation upholds those invariants before adding the `unsafe` keyword
+help: add `unsafe` to this trait implementation
+   |
+LL | unsafe impl<#[may_dangle] 'a, 'b, B: fmt::Debug> Drop for Pr<'a, 'b, B> {
+   | ++++++
 
 error: aborting due to 2 previous errors
 
diff --git a/src/test/ui/issues/issue-54943-1.rs b/src/test/ui/dropck/issue-54943-1.rs
similarity index 100%
rename from src/test/ui/issues/issue-54943-1.rs
rename to src/test/ui/dropck/issue-54943-1.rs
diff --git a/src/test/ui/issues/issue-54943-2.rs b/src/test/ui/dropck/issue-54943-2.rs
similarity index 100%
rename from src/test/ui/issues/issue-54943-2.rs
rename to src/test/ui/dropck/issue-54943-2.rs
diff --git a/src/test/ui/dyn-star/issue-102430.rs b/src/test/ui/dyn-star/issue-102430.rs
new file mode 100644
index 000000000000..244ecda6626a
--- /dev/null
+++ b/src/test/ui/dyn-star/issue-102430.rs
@@ -0,0 +1,32 @@
+// check-pass
+
+#![feature(dyn_star)]
+#![allow(incomplete_features)]
+
+trait AddOne {
+    fn add1(&mut self) -> usize;
+}
+
+impl AddOne for usize {
+    fn add1(&mut self) -> usize {
+        *self += 1;
+        *self
+    }
+}
+
+impl AddOne for &mut usize {
+    fn add1(&mut self) -> usize {
+        (*self).add1()
+    }
+}
+
+fn add_one(mut i: dyn* AddOne + '_) -> usize {
+    i.add1()
+}
+
+fn main() {
+    let mut x = 42usize;
+    let y = &mut x as (dyn* AddOne + '_);
+
+    println!("{}", add_one(y));
+}
diff --git a/src/test/ui/dyn-star/no-explicit-dyn-star-cast.rs b/src/test/ui/dyn-star/no-explicit-dyn-star-cast.rs
new file mode 100644
index 000000000000..67240c8e8da0
--- /dev/null
+++ b/src/test/ui/dyn-star/no-explicit-dyn-star-cast.rs
@@ -0,0 +1,13 @@
+use std::fmt::Debug;
+
+fn make_dyn_star() {
+    let i = 42usize;
+    let dyn_i: dyn* Debug = i as dyn* Debug;
+    //~^ ERROR casting `usize` as `dyn* Debug` is invalid
+    //~| ERROR dyn* trait objects are unstable
+    //~| ERROR dyn* trait objects are unstable
+}
+
+fn main() {
+    make_dyn_star();
+}
diff --git a/src/test/ui/dyn-star/no-explicit-dyn-star-cast.stderr b/src/test/ui/dyn-star/no-explicit-dyn-star-cast.stderr
new file mode 100644
index 000000000000..687d7db04647
--- /dev/null
+++ b/src/test/ui/dyn-star/no-explicit-dyn-star-cast.stderr
@@ -0,0 +1,28 @@
+error[E0658]: dyn* trait objects are unstable
+  --> $DIR/no-explicit-dyn-star-cast.rs:5:16
+   |
+LL |     let dyn_i: dyn* Debug = i as dyn* Debug;
+   |                ^^^^^^^^^^
+   |
+   = note: see issue #91611 <https://github.com/rust-lang/rust/issues/91611> for more information
+   = help: add `#![feature(dyn_star)]` to the crate attributes to enable
+
+error[E0658]: dyn* trait objects are unstable
+  --> $DIR/no-explicit-dyn-star-cast.rs:5:34
+   |
+LL |     let dyn_i: dyn* Debug = i as dyn* Debug;
+   |                                  ^^^^^^^^^^
+   |
+   = note: see issue #91611 <https://github.com/rust-lang/rust/issues/91611> for more information
+   = help: add `#![feature(dyn_star)]` to the crate attributes to enable
+
+error[E0606]: casting `usize` as `dyn* Debug` is invalid
+  --> $DIR/no-explicit-dyn-star-cast.rs:5:29
+   |
+LL |     let dyn_i: dyn* Debug = i as dyn* Debug;
+   |                             ^^^^^^^^^^^^^^^
+
+error: aborting due to 3 previous errors
+
+Some errors have detailed explanations: E0606, E0658.
+For more information about an error, try `rustc --explain E0606`.
diff --git a/src/test/ui/dyn-star/no-explicit-dyn-star.rs b/src/test/ui/dyn-star/no-explicit-dyn-star.rs
new file mode 100644
index 000000000000..4f726b7c6a69
--- /dev/null
+++ b/src/test/ui/dyn-star/no-explicit-dyn-star.rs
@@ -0,0 +1,8 @@
+// aux-build:dyn-star-foreign.rs
+
+extern crate dyn_star_foreign;
+
+fn main() {
+    dyn_star_foreign::require_dyn_star_display(1usize as _);
+    //~^ ERROR casting `usize` as `dyn* std::fmt::Display` is invalid
+}
diff --git a/src/test/ui/dyn-star/no-explicit-dyn-star.stderr b/src/test/ui/dyn-star/no-explicit-dyn-star.stderr
new file mode 100644
index 000000000000..49706fae19e2
--- /dev/null
+++ b/src/test/ui/dyn-star/no-explicit-dyn-star.stderr
@@ -0,0 +1,9 @@
+error[E0606]: casting `usize` as `dyn* std::fmt::Display` is invalid
+  --> $DIR/no-explicit-dyn-star.rs:6:48
+   |
+LL |     dyn_star_foreign::require_dyn_star_display(1usize as _);
+   |                                                ^^^^^^^^^^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0606`.
diff --git a/src/test/ui/editions/edition-keywords-2015-2015-parsing.stderr b/src/test/ui/editions/edition-keywords-2015-2015-parsing.stderr
index 3435fdfd7257..39944622d07b 100644
--- a/src/test/ui/editions/edition-keywords-2015-2015-parsing.stderr
+++ b/src/test/ui/editions/edition-keywords-2015-2015-parsing.stderr
@@ -3,12 +3,24 @@ error: no rules expected the token `r#async`
    |
 LL |     r#async = consumes_async!(r#async);
    |                               ^^^^^^^ no rules expected this token in macro call
+   |
+note: while trying to match `async`
+  --> $DIR/auxiliary/edition-kw-macro-2015.rs:17:6
+   |
+LL |     (async) => (1)
+   |      ^^^^^
 
 error: no rules expected the token `async`
   --> $DIR/edition-keywords-2015-2015-parsing.rs:17:35
    |
 LL |     r#async = consumes_async_raw!(async);
    |                                   ^^^^^ no rules expected this token in macro call
+   |
+note: while trying to match `r#async`
+  --> $DIR/auxiliary/edition-kw-macro-2015.rs:22:6
+   |
+LL |     (r#async) => (1)
+   |      ^^^^^^^
 
 error: aborting due to 2 previous errors
 
diff --git a/src/test/ui/editions/edition-keywords-2015-2018-parsing.stderr b/src/test/ui/editions/edition-keywords-2015-2018-parsing.stderr
index 6e86d746f544..fa83908e6666 100644
--- a/src/test/ui/editions/edition-keywords-2015-2018-parsing.stderr
+++ b/src/test/ui/editions/edition-keywords-2015-2018-parsing.stderr
@@ -3,12 +3,24 @@ error: no rules expected the token `r#async`
    |
 LL |     r#async = consumes_async!(r#async);
    |                               ^^^^^^^ no rules expected this token in macro call
+   |
+note: while trying to match `async`
+  --> $DIR/auxiliary/edition-kw-macro-2018.rs:17:6
+   |
+LL |     (async) => (1)
+   |      ^^^^^
 
 error: no rules expected the token `async`
   --> $DIR/edition-keywords-2015-2018-parsing.rs:17:35
    |
 LL |     r#async = consumes_async_raw!(async);
    |                                   ^^^^^ no rules expected this token in macro call
+   |
+note: while trying to match `r#async`
+  --> $DIR/auxiliary/edition-kw-macro-2018.rs:22:6
+   |
+LL |     (r#async) => (1)
+   |      ^^^^^^^
 
 error: aborting due to 2 previous errors
 
diff --git a/src/test/ui/editions/edition-keywords-2018-2015-parsing.stderr b/src/test/ui/editions/edition-keywords-2018-2015-parsing.stderr
index e1eea725bb0b..1a4a94e97332 100644
--- a/src/test/ui/editions/edition-keywords-2018-2015-parsing.stderr
+++ b/src/test/ui/editions/edition-keywords-2018-2015-parsing.stderr
@@ -25,12 +25,24 @@ error: no rules expected the token `r#async`
    |
 LL |     r#async = consumes_async!(r#async);
    |                               ^^^^^^^ no rules expected this token in macro call
+   |
+note: while trying to match `async`
+  --> $DIR/auxiliary/edition-kw-macro-2015.rs:17:6
+   |
+LL |     (async) => (1)
+   |      ^^^^^
 
 error: no rules expected the token `async`
   --> $DIR/edition-keywords-2018-2015-parsing.rs:21:35
    |
 LL |     r#async = consumes_async_raw!(async);
    |                                   ^^^^^ no rules expected this token in macro call
+   |
+note: while trying to match `r#async`
+  --> $DIR/auxiliary/edition-kw-macro-2015.rs:22:6
+   |
+LL |     (r#async) => (1)
+   |      ^^^^^^^
 
 error: macro expansion ends with an incomplete expression: expected one of `move`, `|`, or `||`
   --> $DIR/auxiliary/edition-kw-macro-2015.rs:27:23
diff --git a/src/test/ui/editions/edition-keywords-2018-2018-parsing.stderr b/src/test/ui/editions/edition-keywords-2018-2018-parsing.stderr
index 0af4da09c19e..19eb7ac98239 100644
--- a/src/test/ui/editions/edition-keywords-2018-2018-parsing.stderr
+++ b/src/test/ui/editions/edition-keywords-2018-2018-parsing.stderr
@@ -25,12 +25,24 @@ error: no rules expected the token `r#async`
    |
 LL |     r#async = consumes_async!(r#async);
    |                               ^^^^^^^ no rules expected this token in macro call
+   |
+note: while trying to match `async`
+  --> $DIR/auxiliary/edition-kw-macro-2018.rs:17:6
+   |
+LL |     (async) => (1)
+   |      ^^^^^
 
 error: no rules expected the token `async`
   --> $DIR/edition-keywords-2018-2018-parsing.rs:21:35
    |
 LL |     r#async = consumes_async_raw!(async);
    |                                   ^^^^^ no rules expected this token in macro call
+   |
+note: while trying to match `r#async`
+  --> $DIR/auxiliary/edition-kw-macro-2018.rs:22:6
+   |
+LL |     (r#async) => (1)
+   |      ^^^^^^^
 
 error: macro expansion ends with an incomplete expression: expected one of `move`, `|`, or `||`
   --> $DIR/auxiliary/edition-kw-macro-2018.rs:27:23
diff --git a/src/test/ui/empty/empty-comment.stderr b/src/test/ui/empty/empty-comment.stderr
index f583dbbdc64f..7cc8d8fe9229 100644
--- a/src/test/ui/empty/empty-comment.stderr
+++ b/src/test/ui/empty/empty-comment.stderr
@@ -6,6 +6,12 @@ LL | macro_rules! one_arg_macro {
 ...
 LL |     one_arg_macro!(/**/);
    |     ^^^^^^^^^^^^^^^^^^^^ missing tokens in macro arguments
+   |
+note: while trying to match meta-variable `$fmt:expr`
+  --> $DIR/empty-comment.rs:6:6
+   |
+LL |     ($fmt:expr) => (print!(concat!($fmt, "\n")));
+   |      ^^^^^^^^^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/enum-discriminant/arbitrary_enum_discriminant-no-repr.rs b/src/test/ui/enum-discriminant/arbitrary_enum_discriminant-no-repr.rs
index 4da7b5ab24b2..a6e5f70fdefa 100644
--- a/src/test/ui/enum-discriminant/arbitrary_enum_discriminant-no-repr.rs
+++ b/src/test/ui/enum-discriminant/arbitrary_enum_discriminant-no-repr.rs
@@ -1,5 +1,4 @@
 #![crate_type="lib"]
-#![feature(arbitrary_enum_discriminant)]
 
 enum Enum {
 //~^ ERROR `#[repr(inttype)]` must be specified
diff --git a/src/test/ui/enum-discriminant/arbitrary_enum_discriminant-no-repr.stderr b/src/test/ui/enum-discriminant/arbitrary_enum_discriminant-no-repr.stderr
index 803bb06fcc21..8cee74696295 100644
--- a/src/test/ui/enum-discriminant/arbitrary_enum_discriminant-no-repr.stderr
+++ b/src/test/ui/enum-discriminant/arbitrary_enum_discriminant-no-repr.stderr
@@ -1,5 +1,5 @@
 error[E0732]: `#[repr(inttype)]` must be specified
-  --> $DIR/arbitrary_enum_discriminant-no-repr.rs:4:1
+  --> $DIR/arbitrary_enum_discriminant-no-repr.rs:3:1
    |
 LL | enum Enum {
    | ^^^^^^^^^
diff --git a/src/test/ui/enum-discriminant/arbitrary_enum_discriminant.rs b/src/test/ui/enum-discriminant/arbitrary_enum_discriminant.rs
index ccc423e4a194..83e74a6e685a 100644
--- a/src/test/ui/enum-discriminant/arbitrary_enum_discriminant.rs
+++ b/src/test/ui/enum-discriminant/arbitrary_enum_discriminant.rs
@@ -1,5 +1,5 @@
 // run-pass
-#![feature(arbitrary_enum_discriminant, test)]
+#![feature(test)]
 
 extern crate test;
 
diff --git a/src/test/ui/enum-discriminant/discriminant_value.rs b/src/test/ui/enum-discriminant/discriminant_value.rs
index 65ab411dbcbe..f3dfac298ad7 100644
--- a/src/test/ui/enum-discriminant/discriminant_value.rs
+++ b/src/test/ui/enum-discriminant/discriminant_value.rs
@@ -1,6 +1,6 @@
 // run-pass
 #![allow(stable_features)]
-#![feature(arbitrary_enum_discriminant, core, core_intrinsics)]
+#![feature(core, core_intrinsics)]
 
 extern crate core;
 use core::intrinsics::discriminant_value;
diff --git a/src/test/ui/enum-discriminant/feature-gate-arbitrary_enum_discriminant.rs b/src/test/ui/enum-discriminant/feature-gate-arbitrary_enum_discriminant.rs
deleted file mode 100644
index 3e90af4d36af..000000000000
--- a/src/test/ui/enum-discriminant/feature-gate-arbitrary_enum_discriminant.rs
+++ /dev/null
@@ -1,10 +0,0 @@
-#![crate_type="lib"]
-
-enum Enum {
-  Unit = 1,
-  //~^ ERROR custom discriminant values are not allowed in enums with tuple or struct variants
-  Tuple() = 2,
-  //~^ ERROR discriminants on non-unit variants are experimental
-  Struct{} = 3,
-  //~^ ERROR discriminants on non-unit variants are experimental
-}
diff --git a/src/test/ui/enum-discriminant/feature-gate-arbitrary_enum_discriminant.stderr b/src/test/ui/enum-discriminant/feature-gate-arbitrary_enum_discriminant.stderr
deleted file mode 100644
index b5f61e6e991d..000000000000
--- a/src/test/ui/enum-discriminant/feature-gate-arbitrary_enum_discriminant.stderr
+++ /dev/null
@@ -1,36 +0,0 @@
-error[E0658]: discriminants on non-unit variants are experimental
-  --> $DIR/feature-gate-arbitrary_enum_discriminant.rs:6:13
-   |
-LL |   Tuple() = 2,
-   |             ^
-   |
-   = note: see issue #60553 <https://github.com/rust-lang/rust/issues/60553> for more information
-   = help: add `#![feature(arbitrary_enum_discriminant)]` to the crate attributes to enable
-
-error[E0658]: discriminants on non-unit variants are experimental
-  --> $DIR/feature-gate-arbitrary_enum_discriminant.rs:8:14
-   |
-LL |   Struct{} = 3,
-   |              ^
-   |
-   = note: see issue #60553 <https://github.com/rust-lang/rust/issues/60553> for more information
-   = help: add `#![feature(arbitrary_enum_discriminant)]` to the crate attributes to enable
-
-error[E0658]: custom discriminant values are not allowed in enums with tuple or struct variants
-  --> $DIR/feature-gate-arbitrary_enum_discriminant.rs:4:10
-   |
-LL |   Unit = 1,
-   |          ^ disallowed custom discriminant
-LL |
-LL |   Tuple() = 2,
-   |   ----------- tuple variant defined here
-LL |
-LL |   Struct{} = 3,
-   |   ------------ struct variant defined here
-   |
-   = note: see issue #60553 <https://github.com/rust-lang/rust/issues/60553> for more information
-   = help: add `#![feature(arbitrary_enum_discriminant)]` to the crate attributes to enable
-
-error: aborting due to 3 previous errors
-
-For more information about this error, try `rustc --explain E0658`.
diff --git a/src/test/ui/enum-discriminant/get_discr.rs b/src/test/ui/enum-discriminant/get_discr.rs
new file mode 100644
index 000000000000..71eea4e0f78a
--- /dev/null
+++ b/src/test/ui/enum-discriminant/get_discr.rs
@@ -0,0 +1,114 @@
+// run-pass
+
+// Now that there are several variations on the code generated in
+// `codegen_get_discr`, let's make sure the various cases yield the correct
+// result.
+
+// To get the discriminant of an E<X1> value, there are no shortcuts - we must
+// do the full algorithm.
+#[repr(u8)]
+pub enum X1 {
+    _1 = 1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16,
+    _17, _18, _19, _20, _21, _22, _23, _24, _25, _26, _27, _28, _29, _30, _31, _32,
+    _33, _34, _35, _36, _37, _38, _39, _40, _41, _42, _43, _44, _45, _46, _47, _48,
+    _49, _50, _51, _52, _53, _54, _55, _56, _57, _58, _59, _60, _61, _62, _63, _64,
+    _65, _66, _67, _68, _69, _70, _71, _72, _73, _74, _75, _76, _77, _78, _79, _80,
+    _81, _82, _83, _84, _85, _86, _87, _88, _89, _90, _91, _92, _93, _94, _95, _96,
+    _97, _98, _99, _100, _101, _102, _103, _104, _105, _106, _107, _108, _109, _110, _111, _112,
+    _113, _114, _115, _116, _117, _118, _119, _120, _121, _122, _123, _124, _125, _126, _127, _128,
+    _129, _130, _131, _132, _133, _134, _135, _136, _137, _138, _139, _140, _141, _142, _143, _144,
+    _145, _146, _147, _148, _149, _150, _151, _152, _153, _154, _155, _156, _157, _158, _159, _160,
+    _161, _162, _163, _164, _165, _166, _167, _168, _169, _170, _171, _172, _173, _174, _175, _176,
+    _177, _178, _179, _180, _181, _182, _183, _184, _185, _186, _187, _188, _189, _190, _191, _192,
+    _193, _194, _195, _196, _197, _198, _199, _200, _201, _202, _203, _204, _205, _206, _207, _208,
+    _209, _210, _211, _212, _213, _214, _215, _216, _217, _218, _219, _220, _221, _222, _223, _224,
+    _225, _226, _227, _228, _229, _230, _231, _232, _233, _234, _235, _236, _237, _238, _239, _240,
+    _241, _242, _243, _244, _245, _246, _247, _248, _249, _250, _251, _252, _253, _254,
+}
+
+#[repr(i8)]
+pub enum X2 {
+    _1 = -1, _2 = 0, _3 = 1,
+}
+
+#[repr(i8)]
+pub enum X3 {
+    _1 = -128, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16,
+    _17, _18, _19, _20, _21, _22, _23, _24, _25, _26, _27, _28, _29, _30, _31, _32,
+    _33, _34, _35, _36, _37, _38, _39, _40, _41, _42, _43, _44, _45, _46, _47, _48,
+    _49, _50, _51, _52, _53, _54, _55, _56, _57, _58, _59, _60, _61, _62, _63, _64,
+    _65, _66, _67, _68, _69, _70, _71, _72, _73, _74, _75, _76, _77, _78, _79, _80,
+    _81, _82, _83, _84, _85, _86, _87, _88, _89, _90, _91, _92, _93, _94, _95, _96,
+    _97, _98, _99, _100, _101, _102, _103, _104, _105, _106, _107, _108, _109, _110, _111, _112,
+    _113, _114, _115, _116, _117, _118, _119, _120, _121, _122, _123, _124, _125, _126, _127, _128,
+    _129, _130, _131, _132, _133, _134, _135, _136, _137, _138, _139, _140, _141, _142, _143, _144,
+    _145, _146, _147, _148, _149, _150, _151, _152, _153, _154, _155, _156, _157, _158, _159, _160,
+    _161, _162, _163, _164, _165, _166, _167, _168, _169, _170, _171, _172, _173, _174, _175, _176,
+    _177, _178, _179, _180, _181, _182, _183, _184, _185, _186, _187, _188, _189, _190, _191, _192,
+    _193, _194, _195, _196, _197, _198, _199, _200, _201, _202, _203, _204, _205, _206, _207, _208,
+    _209, _210, _211, _212, _213, _214, _215, _216, _217, _218, _219, _220, _221, _222, _223, _224,
+    _225, _226, _227, _228, _229, _230, _231, _232, _233, _234, _235, _236, _237, _238, _239, _240,
+    _241, _242, _243, _244, _245, _246, _247, _248, _249, _250, _251, _252, _253, _254,
+}
+
+#[repr(i8)]
+pub enum X4 {
+    _1 = -126, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16,
+    _17, _18, _19, _20, _21, _22, _23, _24, _25, _26, _27, _28, _29, _30, _31, _32,
+    _33, _34, _35, _36, _37, _38, _39, _40, _41, _42, _43, _44, _45, _46, _47, _48,
+    _49, _50, _51, _52, _53, _54, _55, _56, _57, _58, _59, _60, _61, _62, _63, _64,
+    _65, _66, _67, _68, _69, _70, _71, _72, _73, _74, _75, _76, _77, _78, _79, _80,
+    _81, _82, _83, _84, _85, _86, _87, _88, _89, _90, _91, _92, _93, _94, _95, _96,
+    _97, _98, _99, _100, _101, _102, _103, _104, _105, _106, _107, _108, _109, _110, _111, _112,
+    _113, _114, _115, _116, _117, _118, _119, _120, _121, _122, _123, _124, _125, _126, _127, _128,
+    _129, _130, _131, _132, _133, _134, _135, _136, _137, _138, _139, _140, _141, _142, _143, _144,
+    _145, _146, _147, _148, _149, _150, _151, _152, _153, _154, _155, _156, _157, _158, _159, _160,
+    _161, _162, _163, _164, _165, _166, _167, _168, _169, _170, _171, _172, _173, _174, _175, _176,
+    _177, _178, _179, _180, _181, _182, _183, _184, _185, _186, _187, _188, _189, _190, _191, _192,
+    _193, _194, _195, _196, _197, _198, _199, _200, _201, _202, _203, _204, _205, _206, _207, _208,
+    _209, _210, _211, _212, _213, _214, _215, _216, _217, _218, _219, _220, _221, _222, _223, _224,
+    _225, _226, _227, _228, _229, _230, _231, _232, _233, _234, _235, _236, _237, _238, _239, _240,
+    _241, _242, _243, _244, _245, _246, _247, _248, _249, _250, _251, _252, _253, _254,
+}
+
+pub enum E<X> {
+    A(X),
+    B,
+    C,
+}
+
+pub fn match_e<X>(e: E<X>) -> u8 {
+    use E::*;
+    match e {
+        A(_) => 0,
+        B => 1,
+        C => 2,
+    }
+}
+
+fn main() {
+    assert_eq!(match_e(E::A(X1::_1)), 0);
+    assert_eq!(match_e(E::A(X1::_2)), 0);
+    assert_eq!(match_e(E::A(X1::_254)), 0);
+    assert_eq!(match_e(E::<X1>::B), 1);
+    assert_eq!(match_e(E::<X1>::C), 2);
+    assert_eq!(match_e(E::A(X2::_1)), 0);
+    assert_eq!(match_e(E::A(X2::_2)), 0);
+    assert_eq!(match_e(E::A(X2::_3)), 0);
+    assert_eq!(match_e(E::<X2>::B), 1);
+    assert_eq!(match_e(E::<X2>::C), 2);
+    assert_eq!(match_e(E::A(X3::_1)), 0);
+    assert_eq!(match_e(E::A(X3::_2)), 0);
+    assert_eq!(match_e(E::A(X3::_254)), 0);
+    assert_eq!(match_e(E::<X3>::B), 1);
+    assert_eq!(match_e(E::<X3>::C), 2);
+    assert_eq!(match_e(E::A(X4::_1)), 0);
+    assert_eq!(match_e(E::A(X4::_2)), 0);
+    assert_eq!(match_e(E::A(X4::_254)), 0);
+    assert_eq!(match_e(E::<X4>::B), 1);
+    assert_eq!(match_e(E::<X4>::C), 2);
+    assert_eq!(match_e(E::A(false)), 0);
+    assert_eq!(match_e(E::A(true)), 0);
+    assert_eq!(match_e(E::<bool>::B), 1);
+    assert_eq!(match_e(E::<bool>::C), 2);
+}
diff --git a/src/test/ui/issues/issue-46519.rs b/src/test/ui/enum-discriminant/issue-46519.rs
similarity index 100%
rename from src/test/ui/issues/issue-46519.rs
rename to src/test/ui/enum-discriminant/issue-46519.rs
diff --git a/src/test/ui/enum-discriminant/issue-70453-generics-in-discr-ice-2.rs b/src/test/ui/enum-discriminant/issue-70453-generics-in-discr-ice-2.rs
index f927dd189038..ad9fcc25b412 100644
--- a/src/test/ui/enum-discriminant/issue-70453-generics-in-discr-ice-2.rs
+++ b/src/test/ui/enum-discriminant/issue-70453-generics-in-discr-ice-2.rs
@@ -1,4 +1,4 @@
-#![feature(arbitrary_enum_discriminant, core_intrinsics)]
+#![feature(core_intrinsics)]
 
 extern crate core;
 use core::intrinsics::discriminant_value;
diff --git a/src/test/ui/enum-discriminant/issue-70453-polymorphic-ctfe.rs b/src/test/ui/enum-discriminant/issue-70453-polymorphic-ctfe.rs
index e62582fb5161..42a062239d34 100644
--- a/src/test/ui/enum-discriminant/issue-70453-polymorphic-ctfe.rs
+++ b/src/test/ui/enum-discriminant/issue-70453-polymorphic-ctfe.rs
@@ -1,4 +1,4 @@
-#![feature(arbitrary_enum_discriminant, core_intrinsics)]
+#![feature(core_intrinsics)]
 
 extern crate core;
 use core::intrinsics::discriminant_value;
diff --git a/src/test/ui/enum-discriminant/issue-70509-partial_eq.rs b/src/test/ui/enum-discriminant/issue-70509-partial_eq.rs
index ae389e114664..3adac7b72621 100644
--- a/src/test/ui/enum-discriminant/issue-70509-partial_eq.rs
+++ b/src/test/ui/enum-discriminant/issue-70509-partial_eq.rs
@@ -1,5 +1,5 @@
 // run-pass
-#![feature(repr128, arbitrary_enum_discriminant)]
+#![feature(repr128)]
 //~^ WARN the feature `repr128` is incomplete
 
 #[derive(PartialEq, Debug)]
diff --git a/src/test/ui/enum-discriminant/issue-70509-partial_eq.stderr b/src/test/ui/enum-discriminant/issue-70509-partial_eq.stderr
index ac93badf2156..2eef930c3943 100644
--- a/src/test/ui/enum-discriminant/issue-70509-partial_eq.stderr
+++ b/src/test/ui/enum-discriminant/issue-70509-partial_eq.stderr
@@ -1,7 +1,7 @@
 warning: the feature `repr128` is incomplete and may not be safe to use and/or cause compiler crashes
   --> $DIR/issue-70509-partial_eq.rs:2:12
    |
-LL | #![feature(repr128, arbitrary_enum_discriminant)]
+LL | #![feature(repr128)]
    |            ^^^^^^^
    |
    = note: see issue #56071 <https://github.com/rust-lang/rust/issues/56071> for more information
diff --git a/src/test/ui/error-codes/E0045.stderr b/src/test/ui/error-codes/E0045.stderr
index d163128bc8b6..fcc613b11b8d 100644
--- a/src/test/ui/error-codes/E0045.stderr
+++ b/src/test/ui/error-codes/E0045.stderr
@@ -1,8 +1,8 @@
-error[E0045]: C-variadic function must have C or cdecl calling convention
+error[E0045]: C-variadic function must have a compatible calling convention, like `C` or `cdecl`
   --> $DIR/E0045.rs:1:17
    |
 LL | extern "Rust" { fn foo(x: u8, ...); }
-   |                 ^^^^^^^^^^^^^^^^^^^ C-variadics require C or cdecl calling convention
+   |                 ^^^^^^^^^^^^^^^^^^^ C-variadic function must have a compatible calling convention
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/error-codes/E0059.stderr b/src/test/ui/error-codes/E0059.stderr
index a1b8aeaedbb8..f331d0142260 100644
--- a/src/test/ui/error-codes/E0059.stderr
+++ b/src/test/ui/error-codes/E0059.stderr
@@ -1,8 +1,14 @@
-error[E0059]: cannot use call notation; the first type parameter for the function trait is neither a tuple nor unit
-  --> $DIR/E0059.rs:3:41
+error[E0059]: type parameter to bare `Fn` trait must be a tuple
+  --> $DIR/E0059.rs:3:11
    |
 LL | fn foo<F: Fn<i32>>(f: F) -> F::Output { f(3) }
-   |                                         ^^^^
+   |           ^^^^^^^ the trait `Tuple` is not implemented for `i32`
+   |
+note: required by a bound in `Fn`
+  --> $SRC_DIR/core/src/ops/function.rs:LL:COL
+   |
+LL | pub trait Fn<Args: Tuple>: FnMut<Args> {
+   |                    ^^^^^ required by this bound in `Fn`
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/error-codes/E0081.stderr b/src/test/ui/error-codes/E0081.stderr
index 64562fefc866..d4b21f6893b4 100644
--- a/src/test/ui/error-codes/E0081.stderr
+++ b/src/test/ui/error-codes/E0081.stderr
@@ -32,7 +32,7 @@ LL |     First = -1,
    |             -- `-1` assigned here
 LL |
 LL |     Second = -2,
-   |     ----------- discriminant for `Last` incremented from this startpoint (`Second` + 1 variant later => `Last` = -1)
+   |     ------ discriminant for `Last` incremented from this startpoint (`Second` + 1 variant later => `Last` = -1)
 LL |
 LL |     Last,
    |     ---- `-1` assigned here
@@ -53,7 +53,7 @@ LL |     V4 = 0,
    |          - `0` assigned here
 LL |
 LL |     V5 = -2,
-   |     ------- discriminant for `V7` incremented from this startpoint (`V5` + 2 variants later => `V7` = 0)
+   |     -- discriminant for `V7` incremented from this startpoint (`V5` + 2 variants later => `V7` = 0)
 ...
 LL |     V7,
    |     -- `0` assigned here
@@ -68,7 +68,7 @@ LL |     V5 = -2,
    |          -- `-2` assigned here
 ...
 LL |     V8 = -3,
-   |     ------- discriminant for `V9` incremented from this startpoint (`V8` + 1 variant later => `V9` = -2)
+   |     -- discriminant for `V9` incremented from this startpoint (`V8` + 1 variant later => `V9` = -2)
 LL |
 LL |     V9,
    |     -- `-2` assigned here
diff --git a/src/test/ui/error-codes/E0199.stderr b/src/test/ui/error-codes/E0199.stderr
index 3632d26cd32e..99d808c0d4b1 100644
--- a/src/test/ui/error-codes/E0199.stderr
+++ b/src/test/ui/error-codes/E0199.stderr
@@ -3,6 +3,12 @@ error[E0199]: implementing the trait `Bar` is not unsafe
    |
 LL | unsafe impl Bar for Foo { }
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: remove `unsafe` from this trait implementation
+   |
+LL - unsafe impl Bar for Foo { }
+LL + impl Bar for Foo { }
+   |
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/error-codes/E0200.stderr b/src/test/ui/error-codes/E0200.stderr
index 677271aad445..1fd86aecee17 100644
--- a/src/test/ui/error-codes/E0200.stderr
+++ b/src/test/ui/error-codes/E0200.stderr
@@ -3,6 +3,12 @@ error[E0200]: the trait `Bar` requires an `unsafe impl` declaration
    |
 LL | impl Bar for Foo { }
    | ^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: the trait `Bar` enforces invariants that the compiler can't check. Review the trait documentation and make sure this implementation upholds those invariants before adding the `unsafe` keyword
+help: add `unsafe` to this trait implementation
+   |
+LL | unsafe impl Bar for Foo { }
+   | ++++++
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/error-codes/E0268.stderr b/src/test/ui/error-codes/E0268.stderr
index c926f9e48749..6422e8a9490e 100644
--- a/src/test/ui/error-codes/E0268.stderr
+++ b/src/test/ui/error-codes/E0268.stderr
@@ -1,8 +1,8 @@
-error[E0268]: `break` outside of a loop
+error[E0268]: `break` outside of a loop or labeled block
   --> $DIR/E0268.rs:2:5
    |
 LL |     break;
-   |     ^^^^^ cannot `break` outside of a loop
+   |     ^^^^^ cannot `break` outside of a loop or labeled block
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/error-codes/E0282.rs b/src/test/ui/error-codes/E0282.rs
index 9bd16abb7bb8..f1f93b3aed61 100644
--- a/src/test/ui/error-codes/E0282.rs
+++ b/src/test/ui/error-codes/E0282.rs
@@ -1,3 +1,4 @@
 fn main() {
-    let x = "hello".chars().rev().collect(); //~ ERROR E0282
+    let x = "hello".chars().rev().collect();
+    //~^ ERROR E0282
 }
diff --git a/src/test/ui/error-codes/E0401.rs b/src/test/ui/error-codes/E0401.rs
index c30e5f471887..8f8d6b87ef20 100644
--- a/src/test/ui/error-codes/E0401.rs
+++ b/src/test/ui/error-codes/E0401.rs
@@ -8,7 +8,9 @@ fn foo<T>(x: T) {
            W: Fn()>
            (y: T) { //~ ERROR E0401
     }
-    bfnr(x); //~ ERROR type annotations needed
+    bfnr(x);
+    //~^ ERROR type annotations needed
+    //~| ERROR type annotations needed
 }
 
 
diff --git a/src/test/ui/error-codes/E0401.stderr b/src/test/ui/error-codes/E0401.stderr
index b0e2ef5b6f7e..9687eca61fab 100644
--- a/src/test/ui/error-codes/E0401.stderr
+++ b/src/test/ui/error-codes/E0401.stderr
@@ -21,7 +21,7 @@ LL |            (y: T) {
    |                ^ use of generic parameter from outer function
 
 error[E0401]: can't use generic parameters from outer function
-  --> $DIR/E0401.rs:22:25
+  --> $DIR/E0401.rs:24:25
    |
 LL | impl<T> Iterator for A<T> {
    | ---- `Self` type implicitly declared here, by this `impl`
@@ -43,7 +43,28 @@ help: consider specifying the generic arguments
 LL |     bfnr::<U, V, W>(x);
    |         +++++++++++
 
-error: aborting due to 4 previous errors
+error[E0283]: type annotations needed
+  --> $DIR/E0401.rs:11:5
+   |
+LL |     bfnr(x);
+   |     ^^^^ cannot infer type of the type parameter `W` declared on the function `bfnr`
+   |
+   = note: multiple `impl`s satisfying `_: Fn<()>` found in the following crates: `alloc`, `core`:
+           - impl<A, F> Fn<A> for &F
+             where A: Tuple, F: Fn<A>, F: ?Sized;
+           - impl<Args, F, A> Fn<Args> for Box<F, A>
+             where Args: Tuple, F: Fn<Args>, A: Allocator, F: ?Sized;
+note: required by a bound in `bfnr`
+  --> $DIR/E0401.rs:4:30
+   |
+LL |     fn bfnr<U, V: Baz<U>, W: Fn()>(y: T) {
+   |                              ^^^^ required by this bound in `bfnr`
+help: consider specifying the type arguments in the function call
+   |
+LL |     bfnr::<U, V, W>(x);
+   |         +++++++++++
 
-Some errors have detailed explanations: E0282, E0401.
+error: aborting due to 5 previous errors
+
+Some errors have detailed explanations: E0282, E0283, E0401.
 For more information about an error, try `rustc --explain E0282`.
diff --git a/src/test/ui/error-codes/E0767.rs b/src/test/ui/error-codes/E0767.rs
index 6c6cb746e6c7..14215d36a383 100644
--- a/src/test/ui/error-codes/E0767.rs
+++ b/src/test/ui/error-codes/E0767.rs
@@ -1,6 +1,7 @@
-fn main () {
+fn main() {
     'a: loop {
         || {
+            //~^ ERROR mismatched types
             loop { break 'a; } //~ ERROR E0767
         }
     }
diff --git a/src/test/ui/error-codes/E0767.stderr b/src/test/ui/error-codes/E0767.stderr
index 2429823306b6..ee85247301c9 100644
--- a/src/test/ui/error-codes/E0767.stderr
+++ b/src/test/ui/error-codes/E0767.stderr
@@ -1,14 +1,27 @@
 error[E0767]: use of unreachable label `'a`
-  --> $DIR/E0767.rs:4:26
+  --> $DIR/E0767.rs:5:26
    |
 LL |     'a: loop {
    |     -- unreachable label defined here
-LL |         || {
+...
 LL |             loop { break 'a; }
    |                          ^^ unreachable label `'a`
    |
    = note: labels are unreachable through functions, closures, async blocks and modules
 
-error: aborting due to previous error
+error[E0308]: mismatched types
+  --> $DIR/E0767.rs:3:9
+   |
+LL | /         || {
+LL | |
+LL | |             loop { break 'a; }
+LL | |         }
+   | |_________^ expected `()`, found closure
+   |
+   = note: expected unit type `()`
+                found closure `[closure@$DIR/E0767.rs:3:9: 3:11]`
 
-For more information about this error, try `rustc --explain E0767`.
+error: aborting due to 2 previous errors
+
+Some errors have detailed explanations: E0308, E0767.
+For more information about an error, try `rustc --explain E0308`.
diff --git a/src/test/ui/error-codes/E0778.rs b/src/test/ui/error-codes/E0778.rs
index 60e5c2598f1e..74653886d415 100644
--- a/src/test/ui/error-codes/E0778.rs
+++ b/src/test/ui/error-codes/E0778.rs
@@ -1,8 +1,4 @@
-#![feature(isa_attribute)]
-
 #[instruction_set()] //~ ERROR
-fn no_isa_defined() {
-}
+fn no_isa_defined() {}
 
-fn main() {
-}
+fn main() {}
diff --git a/src/test/ui/error-codes/E0778.stderr b/src/test/ui/error-codes/E0778.stderr
index 6ecae7924237..42647e5c6a1b 100644
--- a/src/test/ui/error-codes/E0778.stderr
+++ b/src/test/ui/error-codes/E0778.stderr
@@ -1,5 +1,5 @@
 error[E0778]: `#[instruction_set]` requires an argument
-  --> $DIR/E0778.rs:3:1
+  --> $DIR/E0778.rs:1:1
    |
 LL | #[instruction_set()]
    | ^^^^^^^^^^^^^^^^^^^^
diff --git a/src/test/ui/error-codes/E0779.rs b/src/test/ui/error-codes/E0779.rs
index 1b4dbce20360..c32dae12c9cb 100644
--- a/src/test/ui/error-codes/E0779.rs
+++ b/src/test/ui/error-codes/E0779.rs
@@ -1,6 +1,2 @@
-#![feature(isa_attribute)]
-
 #[instruction_set(arm::magic)] //~ ERROR
-fn main() {
-
-}
+fn main() {}
diff --git a/src/test/ui/error-codes/E0779.stderr b/src/test/ui/error-codes/E0779.stderr
index da787260d4f6..7c6a119a0961 100644
--- a/src/test/ui/error-codes/E0779.stderr
+++ b/src/test/ui/error-codes/E0779.stderr
@@ -1,5 +1,5 @@
 error[E0779]: invalid instruction set specified
-  --> $DIR/E0779.rs:3:1
+  --> $DIR/E0779.rs:1:1
    |
 LL | #[instruction_set(arm::magic)]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/src/test/ui/error-codes/e0119/conflict-with-std.stderr b/src/test/ui/error-codes/e0119/conflict-with-std.stderr
index 3ff96a6a4d65..ef888a1c2871 100644
--- a/src/test/ui/error-codes/e0119/conflict-with-std.stderr
+++ b/src/test/ui/error-codes/e0119/conflict-with-std.stderr
@@ -1,4 +1,4 @@
-error[E0119]: conflicting implementations of trait `std::convert::AsRef<Q>` for type `std::boxed::Box<Q>`
+error[E0119]: conflicting implementations of trait `AsRef<Q>` for type `Box<Q>`
   --> $DIR/conflict-with-std.rs:5:1
    |
 LL | impl AsRef<Q> for Box<Q> {
@@ -8,7 +8,7 @@ LL | impl AsRef<Q> for Box<Q> {
            - impl<T, A> AsRef<T> for Box<T, A>
              where A: Allocator, T: ?Sized;
 
-error[E0119]: conflicting implementations of trait `std::convert::From<S>` for type `S`
+error[E0119]: conflicting implementations of trait `From<S>` for type `S`
   --> $DIR/conflict-with-std.rs:12:1
    |
 LL | impl From<S> for S {
@@ -17,7 +17,7 @@ LL | impl From<S> for S {
    = note: conflicting implementation in crate `core`:
            - impl<T> From<T> for T;
 
-error[E0119]: conflicting implementations of trait `std::convert::TryFrom<X>` for type `X`
+error[E0119]: conflicting implementations of trait `TryFrom<X>` for type `X`
   --> $DIR/conflict-with-std.rs:19:1
    |
 LL | impl TryFrom<X> for X {
diff --git a/src/test/ui/error-codes/e0119/issue-23563.stderr b/src/test/ui/error-codes/e0119/issue-23563.stderr
index f149cef587f2..1b2d64282e1e 100644
--- a/src/test/ui/error-codes/e0119/issue-23563.stderr
+++ b/src/test/ui/error-codes/e0119/issue-23563.stderr
@@ -1,4 +1,4 @@
-error[E0119]: conflicting implementations of trait `a::LolFrom<&[_]>` for type `LocalType<_>`
+error[E0119]: conflicting implementations of trait `LolFrom<&[_]>` for type `LocalType<_>`
   --> $DIR/issue-23563.rs:13:1
    |
 LL | impl<'a, T> LolFrom<&'a [T]> for LocalType<T> {
diff --git a/src/test/ui/error-codes/e0119/issue-27403.stderr b/src/test/ui/error-codes/e0119/issue-27403.stderr
index c11a50487479..9b3345c23bb2 100644
--- a/src/test/ui/error-codes/e0119/issue-27403.stderr
+++ b/src/test/ui/error-codes/e0119/issue-27403.stderr
@@ -1,4 +1,4 @@
-error[E0119]: conflicting implementations of trait `std::convert::Into<_>` for type `GenX<_>`
+error[E0119]: conflicting implementations of trait `Into<_>` for type `GenX<_>`
   --> $DIR/issue-27403.rs:5:1
    |
 LL | impl<S> Into<S> for GenX<S> {
diff --git a/src/test/ui/error-codes/e0119/so-37347311.stderr b/src/test/ui/error-codes/e0119/so-37347311.stderr
index f1c2b0d29742..99367e808419 100644
--- a/src/test/ui/error-codes/e0119/so-37347311.stderr
+++ b/src/test/ui/error-codes/e0119/so-37347311.stderr
@@ -1,4 +1,4 @@
-error[E0119]: conflicting implementations of trait `std::convert::From<MyError<_>>` for type `MyError<_>`
+error[E0119]: conflicting implementations of trait `From<MyError<_>>` for type `MyError<_>`
   --> $DIR/so-37347311.rs:11:1
    |
 LL | impl<S: Storage> From<S::Error> for MyError<S> {
diff --git a/src/test/ui/fail-simple.stderr b/src/test/ui/fail-simple.stderr
index 26ed918e94d9..af8f54291ff4 100644
--- a/src/test/ui/fail-simple.stderr
+++ b/src/test/ui/fail-simple.stderr
@@ -3,6 +3,8 @@ error: no rules expected the token `@`
    |
 LL |     panic!(@);
    |            ^ no rules expected this token in macro call
+   |
+   = note: while trying to match end of macro
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/feature-gates/feature-gate-abi-efiapi.rs b/src/test/ui/feature-gates/feature-gate-abi-efiapi.rs
new file mode 100644
index 000000000000..0c0d736acd04
--- /dev/null
+++ b/src/test/ui/feature-gates/feature-gate-abi-efiapi.rs
@@ -0,0 +1,33 @@
+// needs-llvm-components: x86
+// compile-flags: --target=x86_64-unknown-linux-gnu --crate-type=rlib
+#![no_core]
+#![feature(no_core, lang_items)]
+#[lang="sized"]
+trait Sized { }
+
+// Functions
+extern "efiapi" fn f1() {} //~ ERROR efiapi ABI is experimental
+
+// Methods in trait defintion
+trait Tr {
+    extern "efiapi" fn f2(); //~ ERROR efiapi ABI is experimental
+    extern "efiapi" fn f3() {} //~ ERROR efiapi ABI is experimental
+}
+
+struct S;
+
+// Methods in trait impl
+impl Tr for S {
+    extern "efiapi" fn f2() {} //~ ERROR efiapi ABI is experimental
+}
+
+// Methods in inherent impl
+impl S {
+    extern "efiapi" fn f4() {} //~ ERROR efiapi ABI is experimental
+}
+
+// Function pointer types
+type A = extern "efiapi" fn(); //~ ERROR efiapi ABI is experimental
+
+// Foreign modules
+extern "efiapi" {} //~ ERROR efiapi ABI is experimental
diff --git a/src/test/ui/feature-gates/feature-gate-abi-efiapi.stderr b/src/test/ui/feature-gates/feature-gate-abi-efiapi.stderr
new file mode 100644
index 000000000000..5b01dcc6d859
--- /dev/null
+++ b/src/test/ui/feature-gates/feature-gate-abi-efiapi.stderr
@@ -0,0 +1,66 @@
+error[E0658]: efiapi ABI is experimental and subject to change
+  --> $DIR/feature-gate-abi-efiapi.rs:9:8
+   |
+LL | extern "efiapi" fn f1() {}
+   |        ^^^^^^^^
+   |
+   = note: see issue #65815 <https://github.com/rust-lang/rust/issues/65815> for more information
+   = help: add `#![feature(abi_efiapi)]` to the crate attributes to enable
+
+error[E0658]: efiapi ABI is experimental and subject to change
+  --> $DIR/feature-gate-abi-efiapi.rs:13:12
+   |
+LL |     extern "efiapi" fn f2();
+   |            ^^^^^^^^
+   |
+   = note: see issue #65815 <https://github.com/rust-lang/rust/issues/65815> for more information
+   = help: add `#![feature(abi_efiapi)]` to the crate attributes to enable
+
+error[E0658]: efiapi ABI is experimental and subject to change
+  --> $DIR/feature-gate-abi-efiapi.rs:14:12
+   |
+LL |     extern "efiapi" fn f3() {}
+   |            ^^^^^^^^
+   |
+   = note: see issue #65815 <https://github.com/rust-lang/rust/issues/65815> for more information
+   = help: add `#![feature(abi_efiapi)]` to the crate attributes to enable
+
+error[E0658]: efiapi ABI is experimental and subject to change
+  --> $DIR/feature-gate-abi-efiapi.rs:21:12
+   |
+LL |     extern "efiapi" fn f2() {}
+   |            ^^^^^^^^
+   |
+   = note: see issue #65815 <https://github.com/rust-lang/rust/issues/65815> for more information
+   = help: add `#![feature(abi_efiapi)]` to the crate attributes to enable
+
+error[E0658]: efiapi ABI is experimental and subject to change
+  --> $DIR/feature-gate-abi-efiapi.rs:26:12
+   |
+LL |     extern "efiapi" fn f4() {}
+   |            ^^^^^^^^
+   |
+   = note: see issue #65815 <https://github.com/rust-lang/rust/issues/65815> for more information
+   = help: add `#![feature(abi_efiapi)]` to the crate attributes to enable
+
+error[E0658]: efiapi ABI is experimental and subject to change
+  --> $DIR/feature-gate-abi-efiapi.rs:30:17
+   |
+LL | type A = extern "efiapi" fn();
+   |                 ^^^^^^^^
+   |
+   = note: see issue #65815 <https://github.com/rust-lang/rust/issues/65815> for more information
+   = help: add `#![feature(abi_efiapi)]` to the crate attributes to enable
+
+error[E0658]: efiapi ABI is experimental and subject to change
+  --> $DIR/feature-gate-abi-efiapi.rs:33:8
+   |
+LL | extern "efiapi" {}
+   |        ^^^^^^^^
+   |
+   = note: see issue #65815 <https://github.com/rust-lang/rust/issues/65815> for more information
+   = help: add `#![feature(abi_efiapi)]` to the crate attributes to enable
+
+error: aborting due to 7 previous errors
+
+For more information about this error, try `rustc --explain E0658`.
diff --git a/src/test/ui/feature-gates/feature-gate-abi.rs b/src/test/ui/feature-gates/feature-gate-abi.rs
index 855263595d0b..712655f9775d 100644
--- a/src/test/ui/feature-gates/feature-gate-abi.rs
+++ b/src/test/ui/feature-gates/feature-gate-abi.rs
@@ -1,6 +1,5 @@
 // gate-test-intrinsics
 // gate-test-platform_intrinsics
-// gate-test-abi_efiapi
 // compile-flags: --crate-type=rlib
 
 #![feature(no_core, lang_items)]
@@ -9,13 +8,15 @@
 #[lang="sized"]
 trait Sized { }
 
+#[lang="tuple_trait"]
+trait Tuple { }
+
 // Functions
 extern "rust-intrinsic" fn f1() {} //~ ERROR intrinsics are subject to change
                                    //~^ ERROR intrinsic must be in
 extern "platform-intrinsic" fn f2() {} //~ ERROR platform intrinsics are experimental
                                        //~^ ERROR intrinsic must be in
 extern "rust-call" fn f4(_: ()) {} //~ ERROR rust-call ABI is subject to change
-extern "efiapi" fn f10() {} //~ ERROR efiapi ABI is experimental and subject to change
 
 // Methods in trait definition
 trait Tr {
@@ -24,10 +25,8 @@ trait Tr {
     extern "platform-intrinsic" fn m2(); //~ ERROR platform intrinsics are experimental
                                          //~^ ERROR intrinsic must be in
     extern "rust-call" fn m4(_: ()); //~ ERROR rust-call ABI is subject to change
-    extern "efiapi" fn m10(); //~ ERROR efiapi ABI is experimental and subject to change
 
     extern "rust-call" fn dm4(_: ()) {} //~ ERROR rust-call ABI is subject to change
-    extern "efiapi" fn dm10() {} //~ ERROR efiapi ABI is experimental and subject to change
 }
 
 struct S;
@@ -39,7 +38,6 @@ impl Tr for S {
     extern "platform-intrinsic" fn m2() {} //~ ERROR platform intrinsics are experimental
                                            //~^ ERROR intrinsic must be in
     extern "rust-call" fn m4(_: ()) {} //~ ERROR rust-call ABI is subject to change
-    extern "efiapi" fn m10() {} //~ ERROR efiapi ABI is experimental and subject to change
 }
 
 // Methods in inherent impl
@@ -49,17 +47,14 @@ impl S {
     extern "platform-intrinsic" fn im2() {} //~ ERROR platform intrinsics are experimental
                                             //~^ ERROR intrinsic must be in
     extern "rust-call" fn im4(_: ()) {} //~ ERROR rust-call ABI is subject to change
-    extern "efiapi" fn im10() {} //~ ERROR efiapi ABI is experimental and subject to change
 }
 
 // Function pointer types
 type A1 = extern "rust-intrinsic" fn(); //~ ERROR intrinsics are subject to change
 type A2 = extern "platform-intrinsic" fn(); //~ ERROR platform intrinsics are experimental
 type A4 = extern "rust-call" fn(_: ()); //~ ERROR rust-call ABI is subject to change
-type A10 = extern "efiapi" fn(); //~ ERROR efiapi ABI is experimental and subject to change
 
 // Foreign modules
 extern "rust-intrinsic" {} //~ ERROR intrinsics are subject to change
 extern "platform-intrinsic" {} //~ ERROR platform intrinsics are experimental
 extern "rust-call" {} //~ ERROR rust-call ABI is subject to change
-extern "efiapi" {} //~ ERROR efiapi ABI is experimental and subject to change
diff --git a/src/test/ui/feature-gates/feature-gate-abi.stderr b/src/test/ui/feature-gates/feature-gate-abi.stderr
index bcca39c8fb80..e9791b9513f4 100644
--- a/src/test/ui/feature-gates/feature-gate-abi.stderr
+++ b/src/test/ui/feature-gates/feature-gate-abi.stderr
@@ -1,5 +1,5 @@
 error[E0658]: intrinsics are subject to change
-  --> $DIR/feature-gate-abi.rs:13:8
+  --> $DIR/feature-gate-abi.rs:15:8
    |
 LL | extern "rust-intrinsic" fn f1() {}
    |        ^^^^^^^^^^^^^^^^
@@ -7,7 +7,7 @@ LL | extern "rust-intrinsic" fn f1() {}
    = help: add `#![feature(intrinsics)]` to the crate attributes to enable
 
 error[E0658]: platform intrinsics are experimental and possibly buggy
-  --> $DIR/feature-gate-abi.rs:15:8
+  --> $DIR/feature-gate-abi.rs:17:8
    |
 LL | extern "platform-intrinsic" fn f2() {}
    |        ^^^^^^^^^^^^^^^^^^^^
@@ -16,7 +16,7 @@ LL | extern "platform-intrinsic" fn f2() {}
    = help: add `#![feature(platform_intrinsics)]` to the crate attributes to enable
 
 error[E0658]: rust-call ABI is subject to change
-  --> $DIR/feature-gate-abi.rs:17:8
+  --> $DIR/feature-gate-abi.rs:19:8
    |
 LL | extern "rust-call" fn f4(_: ()) {}
    |        ^^^^^^^^^^^
@@ -24,17 +24,8 @@ LL | extern "rust-call" fn f4(_: ()) {}
    = note: see issue #29625 <https://github.com/rust-lang/rust/issues/29625> for more information
    = help: add `#![feature(unboxed_closures)]` to the crate attributes to enable
 
-error[E0658]: efiapi ABI is experimental and subject to change
-  --> $DIR/feature-gate-abi.rs:18:8
-   |
-LL | extern "efiapi" fn f10() {}
-   |        ^^^^^^^^
-   |
-   = note: see issue #65815 <https://github.com/rust-lang/rust/issues/65815> for more information
-   = help: add `#![feature(abi_efiapi)]` to the crate attributes to enable
-
 error[E0658]: intrinsics are subject to change
-  --> $DIR/feature-gate-abi.rs:22:12
+  --> $DIR/feature-gate-abi.rs:23:12
    |
 LL |     extern "rust-intrinsic" fn m1();
    |            ^^^^^^^^^^^^^^^^
@@ -42,7 +33,7 @@ LL |     extern "rust-intrinsic" fn m1();
    = help: add `#![feature(intrinsics)]` to the crate attributes to enable
 
 error[E0658]: platform intrinsics are experimental and possibly buggy
-  --> $DIR/feature-gate-abi.rs:24:12
+  --> $DIR/feature-gate-abi.rs:25:12
    |
 LL |     extern "platform-intrinsic" fn m2();
    |            ^^^^^^^^^^^^^^^^^^^^
@@ -51,7 +42,7 @@ LL |     extern "platform-intrinsic" fn m2();
    = help: add `#![feature(platform_intrinsics)]` to the crate attributes to enable
 
 error[E0658]: rust-call ABI is subject to change
-  --> $DIR/feature-gate-abi.rs:26:12
+  --> $DIR/feature-gate-abi.rs:27:12
    |
 LL |     extern "rust-call" fn m4(_: ());
    |            ^^^^^^^^^^^
@@ -59,15 +50,6 @@ LL |     extern "rust-call" fn m4(_: ());
    = note: see issue #29625 <https://github.com/rust-lang/rust/issues/29625> for more information
    = help: add `#![feature(unboxed_closures)]` to the crate attributes to enable
 
-error[E0658]: efiapi ABI is experimental and subject to change
-  --> $DIR/feature-gate-abi.rs:27:12
-   |
-LL |     extern "efiapi" fn m10();
-   |            ^^^^^^^^
-   |
-   = note: see issue #65815 <https://github.com/rust-lang/rust/issues/65815> for more information
-   = help: add `#![feature(abi_efiapi)]` to the crate attributes to enable
-
 error[E0658]: rust-call ABI is subject to change
   --> $DIR/feature-gate-abi.rs:29:12
    |
@@ -77,17 +59,8 @@ LL |     extern "rust-call" fn dm4(_: ()) {}
    = note: see issue #29625 <https://github.com/rust-lang/rust/issues/29625> for more information
    = help: add `#![feature(unboxed_closures)]` to the crate attributes to enable
 
-error[E0658]: efiapi ABI is experimental and subject to change
-  --> $DIR/feature-gate-abi.rs:30:12
-   |
-LL |     extern "efiapi" fn dm10() {}
-   |            ^^^^^^^^
-   |
-   = note: see issue #65815 <https://github.com/rust-lang/rust/issues/65815> for more information
-   = help: add `#![feature(abi_efiapi)]` to the crate attributes to enable
-
 error[E0658]: intrinsics are subject to change
-  --> $DIR/feature-gate-abi.rs:37:12
+  --> $DIR/feature-gate-abi.rs:36:12
    |
 LL |     extern "rust-intrinsic" fn m1() {}
    |            ^^^^^^^^^^^^^^^^
@@ -95,7 +68,7 @@ LL |     extern "rust-intrinsic" fn m1() {}
    = help: add `#![feature(intrinsics)]` to the crate attributes to enable
 
 error[E0658]: platform intrinsics are experimental and possibly buggy
-  --> $DIR/feature-gate-abi.rs:39:12
+  --> $DIR/feature-gate-abi.rs:38:12
    |
 LL |     extern "platform-intrinsic" fn m2() {}
    |            ^^^^^^^^^^^^^^^^^^^^
@@ -104,7 +77,7 @@ LL |     extern "platform-intrinsic" fn m2() {}
    = help: add `#![feature(platform_intrinsics)]` to the crate attributes to enable
 
 error[E0658]: rust-call ABI is subject to change
-  --> $DIR/feature-gate-abi.rs:41:12
+  --> $DIR/feature-gate-abi.rs:40:12
    |
 LL |     extern "rust-call" fn m4(_: ()) {}
    |            ^^^^^^^^^^^
@@ -112,17 +85,8 @@ LL |     extern "rust-call" fn m4(_: ()) {}
    = note: see issue #29625 <https://github.com/rust-lang/rust/issues/29625> for more information
    = help: add `#![feature(unboxed_closures)]` to the crate attributes to enable
 
-error[E0658]: efiapi ABI is experimental and subject to change
-  --> $DIR/feature-gate-abi.rs:42:12
-   |
-LL |     extern "efiapi" fn m10() {}
-   |            ^^^^^^^^
-   |
-   = note: see issue #65815 <https://github.com/rust-lang/rust/issues/65815> for more information
-   = help: add `#![feature(abi_efiapi)]` to the crate attributes to enable
-
 error[E0658]: intrinsics are subject to change
-  --> $DIR/feature-gate-abi.rs:47:12
+  --> $DIR/feature-gate-abi.rs:45:12
    |
 LL |     extern "rust-intrinsic" fn im1() {}
    |            ^^^^^^^^^^^^^^^^
@@ -130,7 +94,7 @@ LL |     extern "rust-intrinsic" fn im1() {}
    = help: add `#![feature(intrinsics)]` to the crate attributes to enable
 
 error[E0658]: platform intrinsics are experimental and possibly buggy
-  --> $DIR/feature-gate-abi.rs:49:12
+  --> $DIR/feature-gate-abi.rs:47:12
    |
 LL |     extern "platform-intrinsic" fn im2() {}
    |            ^^^^^^^^^^^^^^^^^^^^
@@ -139,7 +103,7 @@ LL |     extern "platform-intrinsic" fn im2() {}
    = help: add `#![feature(platform_intrinsics)]` to the crate attributes to enable
 
 error[E0658]: rust-call ABI is subject to change
-  --> $DIR/feature-gate-abi.rs:51:12
+  --> $DIR/feature-gate-abi.rs:49:12
    |
 LL |     extern "rust-call" fn im4(_: ()) {}
    |            ^^^^^^^^^^^
@@ -147,17 +111,8 @@ LL |     extern "rust-call" fn im4(_: ()) {}
    = note: see issue #29625 <https://github.com/rust-lang/rust/issues/29625> for more information
    = help: add `#![feature(unboxed_closures)]` to the crate attributes to enable
 
-error[E0658]: efiapi ABI is experimental and subject to change
-  --> $DIR/feature-gate-abi.rs:52:12
-   |
-LL |     extern "efiapi" fn im10() {}
-   |            ^^^^^^^^
-   |
-   = note: see issue #65815 <https://github.com/rust-lang/rust/issues/65815> for more information
-   = help: add `#![feature(abi_efiapi)]` to the crate attributes to enable
-
 error[E0658]: intrinsics are subject to change
-  --> $DIR/feature-gate-abi.rs:56:18
+  --> $DIR/feature-gate-abi.rs:53:18
    |
 LL | type A1 = extern "rust-intrinsic" fn();
    |                  ^^^^^^^^^^^^^^^^
@@ -165,7 +120,7 @@ LL | type A1 = extern "rust-intrinsic" fn();
    = help: add `#![feature(intrinsics)]` to the crate attributes to enable
 
 error[E0658]: platform intrinsics are experimental and possibly buggy
-  --> $DIR/feature-gate-abi.rs:57:18
+  --> $DIR/feature-gate-abi.rs:54:18
    |
 LL | type A2 = extern "platform-intrinsic" fn();
    |                  ^^^^^^^^^^^^^^^^^^^^
@@ -174,7 +129,7 @@ LL | type A2 = extern "platform-intrinsic" fn();
    = help: add `#![feature(platform_intrinsics)]` to the crate attributes to enable
 
 error[E0658]: rust-call ABI is subject to change
-  --> $DIR/feature-gate-abi.rs:58:18
+  --> $DIR/feature-gate-abi.rs:55:18
    |
 LL | type A4 = extern "rust-call" fn(_: ());
    |                  ^^^^^^^^^^^
@@ -182,17 +137,8 @@ LL | type A4 = extern "rust-call" fn(_: ());
    = note: see issue #29625 <https://github.com/rust-lang/rust/issues/29625> for more information
    = help: add `#![feature(unboxed_closures)]` to the crate attributes to enable
 
-error[E0658]: efiapi ABI is experimental and subject to change
-  --> $DIR/feature-gate-abi.rs:59:19
-   |
-LL | type A10 = extern "efiapi" fn();
-   |                   ^^^^^^^^
-   |
-   = note: see issue #65815 <https://github.com/rust-lang/rust/issues/65815> for more information
-   = help: add `#![feature(abi_efiapi)]` to the crate attributes to enable
-
 error[E0658]: intrinsics are subject to change
-  --> $DIR/feature-gate-abi.rs:62:8
+  --> $DIR/feature-gate-abi.rs:58:8
    |
 LL | extern "rust-intrinsic" {}
    |        ^^^^^^^^^^^^^^^^
@@ -200,7 +146,7 @@ LL | extern "rust-intrinsic" {}
    = help: add `#![feature(intrinsics)]` to the crate attributes to enable
 
 error[E0658]: platform intrinsics are experimental and possibly buggy
-  --> $DIR/feature-gate-abi.rs:63:8
+  --> $DIR/feature-gate-abi.rs:59:8
    |
 LL | extern "platform-intrinsic" {}
    |        ^^^^^^^^^^^^^^^^^^^^
@@ -209,7 +155,7 @@ LL | extern "platform-intrinsic" {}
    = help: add `#![feature(platform_intrinsics)]` to the crate attributes to enable
 
 error[E0658]: rust-call ABI is subject to change
-  --> $DIR/feature-gate-abi.rs:64:8
+  --> $DIR/feature-gate-abi.rs:60:8
    |
 LL | extern "rust-call" {}
    |        ^^^^^^^^^^^
@@ -217,63 +163,54 @@ LL | extern "rust-call" {}
    = note: see issue #29625 <https://github.com/rust-lang/rust/issues/29625> for more information
    = help: add `#![feature(unboxed_closures)]` to the crate attributes to enable
 
-error[E0658]: efiapi ABI is experimental and subject to change
-  --> $DIR/feature-gate-abi.rs:65:8
-   |
-LL | extern "efiapi" {}
-   |        ^^^^^^^^
-   |
-   = note: see issue #65815 <https://github.com/rust-lang/rust/issues/65815> for more information
-   = help: add `#![feature(abi_efiapi)]` to the crate attributes to enable
-
 error: intrinsic must be in `extern "rust-intrinsic" { ... }` block
-  --> $DIR/feature-gate-abi.rs:22:32
+  --> $DIR/feature-gate-abi.rs:23:32
    |
 LL |     extern "rust-intrinsic" fn m1();
    |                                ^^
 
 error: intrinsic must be in `extern "rust-intrinsic" { ... }` block
-  --> $DIR/feature-gate-abi.rs:24:36
+  --> $DIR/feature-gate-abi.rs:25:36
    |
 LL |     extern "platform-intrinsic" fn m2();
    |                                    ^^
 
 error: intrinsic must be in `extern "rust-intrinsic" { ... }` block
-  --> $DIR/feature-gate-abi.rs:13:33
+  --> $DIR/feature-gate-abi.rs:15:33
    |
 LL | extern "rust-intrinsic" fn f1() {}
    |                                 ^^
 
 error: intrinsic must be in `extern "rust-intrinsic" { ... }` block
-  --> $DIR/feature-gate-abi.rs:15:37
+  --> $DIR/feature-gate-abi.rs:17:37
    |
 LL | extern "platform-intrinsic" fn f2() {}
    |                                     ^^
 
 error: intrinsic must be in `extern "rust-intrinsic" { ... }` block
-  --> $DIR/feature-gate-abi.rs:37:37
+  --> $DIR/feature-gate-abi.rs:36:37
    |
 LL |     extern "rust-intrinsic" fn m1() {}
    |                                     ^^
 
 error: intrinsic must be in `extern "rust-intrinsic" { ... }` block
-  --> $DIR/feature-gate-abi.rs:39:41
+  --> $DIR/feature-gate-abi.rs:38:41
    |
 LL |     extern "platform-intrinsic" fn m2() {}
    |                                         ^^
 
 error: intrinsic must be in `extern "rust-intrinsic" { ... }` block
-  --> $DIR/feature-gate-abi.rs:47:38
+  --> $DIR/feature-gate-abi.rs:45:38
    |
 LL |     extern "rust-intrinsic" fn im1() {}
    |                                      ^^
 
 error: intrinsic must be in `extern "rust-intrinsic" { ... }` block
-  --> $DIR/feature-gate-abi.rs:49:42
+  --> $DIR/feature-gate-abi.rs:47:42
    |
 LL |     extern "platform-intrinsic" fn im2() {}
    |                                          ^^
 
-error: aborting due to 34 previous errors
+error: aborting due to 27 previous errors
 
 For more information about this error, try `rustc --explain E0658`.
diff --git a/src/test/ui/feature-gates/feature-gate-alloc-error-handler.rs b/src/test/ui/feature-gates/feature-gate-alloc-error-handler.rs
index ad8909618308..78d189d20b64 100644
--- a/src/test/ui/feature-gates/feature-gate-alloc-error-handler.rs
+++ b/src/test/ui/feature-gates/feature-gate-alloc-error-handler.rs
@@ -5,10 +5,12 @@
 
 use core::alloc::Layout;
 
-#[alloc_error_handler] //~ ERROR the `#[alloc_error_handler]` attribute is an experimental feature
+#[alloc_error_handler] //~ ERROR use of unstable library feature 'alloc_error_handler'
 fn oom(info: Layout) -> ! {
     loop {}
 }
 
 #[panic_handler]
-fn panic(_: &core::panic::PanicInfo) -> ! { loop {} }
+fn panic(_: &core::panic::PanicInfo) -> ! {
+    loop {}
+}
diff --git a/src/test/ui/feature-gates/feature-gate-alloc-error-handler.stderr b/src/test/ui/feature-gates/feature-gate-alloc-error-handler.stderr
index 03f31e53f4f2..f414eb463dfb 100644
--- a/src/test/ui/feature-gates/feature-gate-alloc-error-handler.stderr
+++ b/src/test/ui/feature-gates/feature-gate-alloc-error-handler.stderr
@@ -1,8 +1,8 @@
-error[E0658]: the `#[alloc_error_handler]` attribute is an experimental feature
-  --> $DIR/feature-gate-alloc-error-handler.rs:8:1
+error[E0658]: use of unstable library feature 'alloc_error_handler'
+  --> $DIR/feature-gate-alloc-error-handler.rs:8:3
    |
 LL | #[alloc_error_handler]
-   | ^^^^^^^^^^^^^^^^^^^^^^
+   |   ^^^^^^^^^^^^^^^^^^^
    |
    = note: see issue #51540 <https://github.com/rust-lang/rust/issues/51540> for more information
    = help: add `#![feature(alloc_error_handler)]` to the crate attributes to enable
diff --git a/src/test/ui/feature-gates/feature-gate-custom_mir.rs b/src/test/ui/feature-gates/feature-gate-custom_mir.rs
new file mode 100644
index 000000000000..0126dde2f7d4
--- /dev/null
+++ b/src/test/ui/feature-gates/feature-gate-custom_mir.rs
@@ -0,0 +1,12 @@
+#![feature(core_intrinsics)]
+
+extern crate core;
+
+#[custom_mir(dialect = "built")] //~ ERROR the `#[custom_mir]` attribute is just used for the Rust test suite
+pub fn foo(_x: i32) -> i32 {
+    0
+}
+
+fn main() {
+    assert_eq!(2, foo(2));
+}
diff --git a/src/test/ui/feature-gates/feature-gate-custom_mir.stderr b/src/test/ui/feature-gates/feature-gate-custom_mir.stderr
new file mode 100644
index 000000000000..3c149d30d82b
--- /dev/null
+++ b/src/test/ui/feature-gates/feature-gate-custom_mir.stderr
@@ -0,0 +1,11 @@
+error[E0658]: the `#[custom_mir]` attribute is just used for the Rust test suite
+  --> $DIR/feature-gate-custom_mir.rs:5:1
+   |
+LL | #[custom_mir(dialect = "built")]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = help: add `#![feature(custom_mir)]` to the crate attributes to enable
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0658`.
diff --git a/src/test/ui/feature-gates/feature-gate-impl_trait_in_fn_trait_return.rs b/src/test/ui/feature-gates/feature-gate-impl_trait_in_fn_trait_return.rs
new file mode 100644
index 000000000000..0db8088f7eea
--- /dev/null
+++ b/src/test/ui/feature-gates/feature-gate-impl_trait_in_fn_trait_return.rs
@@ -0,0 +1,6 @@
+fn f() -> impl Fn() -> impl Sized { || () }
+//~^ ERROR `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait return
+fn g() -> &'static dyn Fn() -> impl Sized { &|| () }
+//~^ ERROR `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait return
+
+fn main() {}
diff --git a/src/test/ui/feature-gates/feature-gate-impl_trait_in_fn_trait_return.stderr b/src/test/ui/feature-gates/feature-gate-impl_trait_in_fn_trait_return.stderr
new file mode 100644
index 000000000000..c485bc5c3ab9
--- /dev/null
+++ b/src/test/ui/feature-gates/feature-gate-impl_trait_in_fn_trait_return.stderr
@@ -0,0 +1,15 @@
+error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait return
+  --> $DIR/feature-gate-impl_trait_in_fn_trait_return.rs:1:24
+   |
+LL | fn f() -> impl Fn() -> impl Sized { || () }
+   |                        ^^^^^^^^^^
+
+error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait return
+  --> $DIR/feature-gate-impl_trait_in_fn_trait_return.rs:3:32
+   |
+LL | fn g() -> &'static dyn Fn() -> impl Sized { &|| () }
+   |                                ^^^^^^^^^^
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0562`.
diff --git a/src/test/ui/feature-gates/feature-gate-isa_attribute.rs b/src/test/ui/feature-gates/feature-gate-isa_attribute.rs
deleted file mode 100644
index cb02a0955e91..000000000000
--- a/src/test/ui/feature-gates/feature-gate-isa_attribute.rs
+++ /dev/null
@@ -1,6 +0,0 @@
-#[instruction_set]
-//~^ ERROR the `#[instruction_set]` attribute is an experimental feature [E0658]
-//~| ERROR malformed `instruction_set` attribute input
-//~| ERROR must specify an instruction set [E0778]
-fn main() {
-}
diff --git a/src/test/ui/feature-gates/feature-gate-isa_attribute.stderr b/src/test/ui/feature-gates/feature-gate-isa_attribute.stderr
deleted file mode 100644
index 2a95a80ca617..000000000000
--- a/src/test/ui/feature-gates/feature-gate-isa_attribute.stderr
+++ /dev/null
@@ -1,25 +0,0 @@
-error: malformed `instruction_set` attribute input
-  --> $DIR/feature-gate-isa_attribute.rs:1:1
-   |
-LL | #[instruction_set]
-   | ^^^^^^^^^^^^^^^^^^ help: must be of the form: `#[instruction_set(set)]`
-
-error[E0658]: the `#[instruction_set]` attribute is an experimental feature
-  --> $DIR/feature-gate-isa_attribute.rs:1:1
-   |
-LL | #[instruction_set]
-   | ^^^^^^^^^^^^^^^^^^
-   |
-   = note: see issue #74727 <https://github.com/rust-lang/rust/issues/74727> for more information
-   = help: add `#![feature(isa_attribute)]` to the crate attributes to enable
-
-error[E0778]: must specify an instruction set
-  --> $DIR/feature-gate-isa_attribute.rs:1:1
-   |
-LL | #[instruction_set]
-   | ^^^^^^^^^^^^^^^^^^
-
-error: aborting due to 3 previous errors
-
-Some errors have detailed explanations: E0658, E0778.
-For more information about an error, try `rustc --explain E0658`.
diff --git a/src/test/ui/feature-gates/issue-43106-gating-of-builtin-attrs-error.stderr b/src/test/ui/feature-gates/issue-43106-gating-of-builtin-attrs-error.stderr
index 5a645cf4ef98..787670404218 100644
--- a/src/test/ui/feature-gates/issue-43106-gating-of-builtin-attrs-error.stderr
+++ b/src/test/ui/feature-gates/issue-43106-gating-of-builtin-attrs-error.stderr
@@ -110,19 +110,19 @@ error: attribute should be applied to an `extern crate` item
   --> $DIR/issue-43106-gating-of-builtin-attrs-error.rs:25:1
    |
 LL | #![no_link]
-   | ^^^^^^^^^^^
+   | ^^^^^^^^^^^ not an `extern crate` item
 
 error: attribute should be applied to a free function, impl method or static
   --> $DIR/issue-43106-gating-of-builtin-attrs-error.rs:27:1
    |
 LL | #![export_name = "2200"]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^
+   | ^^^^^^^^^^^^^^^^^^^^^^^^ not a free function, impl method or static
 
 error[E0518]: attribute should be applied to function or closure
   --> $DIR/issue-43106-gating-of-builtin-attrs-error.rs:29:1
    |
 LL | #![inline]
-   | ^^^^^^^^^^
+   | ^^^^^^^^^^ not a function or closure
 
 error: `macro_export` attribute cannot be used at crate level
   --> $DIR/issue-43106-gating-of-builtin-attrs-error.rs:12:1
diff --git a/src/test/ui/feature-gates/issue-43106-gating-of-builtin-attrs.rs b/src/test/ui/feature-gates/issue-43106-gating-of-builtin-attrs.rs
index 8db12e55d25c..1fa315f3d215 100644
--- a/src/test/ui/feature-gates/issue-43106-gating-of-builtin-attrs.rs
+++ b/src/test/ui/feature-gates/issue-43106-gating-of-builtin-attrs.rs
@@ -1,6 +1,6 @@
 //~ NOTE not a function
 //~| NOTE not a foreign function or static
-//~| NOTE not a function or static
+//~| NOTE cannot be applied to crates
 //~| NOTE not an `extern` block
 // This test enumerates as many compiler-builtin ungated attributes as
 // possible (that is, all the mutually compatible ones), and checks
diff --git a/src/test/ui/feature-gates/issue-43106-gating-of-builtin-attrs.stderr b/src/test/ui/feature-gates/issue-43106-gating-of-builtin-attrs.stderr
index 310d1f720eb7..30039267979f 100644
--- a/src/test/ui/feature-gates/issue-43106-gating-of-builtin-attrs.stderr
+++ b/src/test/ui/feature-gates/issue-43106-gating-of-builtin-attrs.stderr
@@ -403,7 +403,7 @@ warning: attribute should be applied to a function definition
   --> $DIR/issue-43106-gating-of-builtin-attrs.rs:62:1
    |
 LL | #![cold]
-   | ^^^^^^^^
+   | ^^^^^^^^ cannot be applied to crates
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
 
@@ -411,7 +411,7 @@ warning: attribute should be applied to an `extern` block with non-Rust ABI
   --> $DIR/issue-43106-gating-of-builtin-attrs.rs:64:1
    |
 LL | #![link()]
-   | ^^^^^^^^^^
+   | ^^^^^^^^^^ not an `extern` block
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
 
@@ -419,7 +419,7 @@ warning: attribute should be applied to a foreign function or static
   --> $DIR/issue-43106-gating-of-builtin-attrs.rs:66:1
    |
 LL | #![link_name = "1900"]
-   | ^^^^^^^^^^^^^^^^^^^^^^
+   | ^^^^^^^^^^^^^^^^^^^^^^ not a foreign function or static
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
 
@@ -427,7 +427,7 @@ warning: attribute should be applied to a function or static
   --> $DIR/issue-43106-gating-of-builtin-attrs.rs:69:1
    |
 LL | #![link_section = "1800"]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^ not a function or static
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
 
diff --git a/src/test/ui/fmt/unicode-escape-spans.rs b/src/test/ui/fmt/unicode-escape-spans.rs
new file mode 100644
index 000000000000..753d91ce58e6
--- /dev/null
+++ b/src/test/ui/fmt/unicode-escape-spans.rs
@@ -0,0 +1,19 @@
+fn main() {
+    // 1 byte in UTF-8
+    format!("\u{000041}{a}"); //~ ERROR cannot find value
+    format!("\u{0041}{a}"); //~ ERROR cannot find value
+    format!("\u{41}{a}"); //~ ERROR cannot find value
+    format!("\u{0}{a}"); //~ ERROR cannot find value
+
+    // 2 bytes
+    format!("\u{0df}{a}"); //~ ERROR cannot find value
+    format!("\u{df}{a}"); //~ ERROR cannot find value
+
+    // 3 bytes
+    format!("\u{00211d}{a}"); //~ ERROR cannot find value
+    format!("\u{211d}{a}"); //~ ERROR cannot find value
+
+    // 4 bytes
+    format!("\u{1f4a3}{a}"); //~ ERROR cannot find value
+    format!("\u{10ffff}{a}"); //~ ERROR cannot find value
+}
diff --git a/src/test/ui/fmt/unicode-escape-spans.stderr b/src/test/ui/fmt/unicode-escape-spans.stderr
new file mode 100644
index 000000000000..1d8473f01b82
--- /dev/null
+++ b/src/test/ui/fmt/unicode-escape-spans.stderr
@@ -0,0 +1,63 @@
+error[E0425]: cannot find value `a` in this scope
+  --> $DIR/unicode-escape-spans.rs:3:25
+   |
+LL |     format!("\u{000041}{a}");
+   |                         ^ not found in this scope
+
+error[E0425]: cannot find value `a` in this scope
+  --> $DIR/unicode-escape-spans.rs:4:23
+   |
+LL |     format!("\u{0041}{a}");
+   |                       ^ not found in this scope
+
+error[E0425]: cannot find value `a` in this scope
+  --> $DIR/unicode-escape-spans.rs:5:21
+   |
+LL |     format!("\u{41}{a}");
+   |                     ^ not found in this scope
+
+error[E0425]: cannot find value `a` in this scope
+  --> $DIR/unicode-escape-spans.rs:6:20
+   |
+LL |     format!("\u{0}{a}");
+   |                    ^ not found in this scope
+
+error[E0425]: cannot find value `a` in this scope
+  --> $DIR/unicode-escape-spans.rs:9:22
+   |
+LL |     format!("\u{0df}{a}");
+   |                      ^ not found in this scope
+
+error[E0425]: cannot find value `a` in this scope
+  --> $DIR/unicode-escape-spans.rs:10:21
+   |
+LL |     format!("\u{df}{a}");
+   |                     ^ not found in this scope
+
+error[E0425]: cannot find value `a` in this scope
+  --> $DIR/unicode-escape-spans.rs:13:25
+   |
+LL |     format!("\u{00211d}{a}");
+   |                         ^ not found in this scope
+
+error[E0425]: cannot find value `a` in this scope
+  --> $DIR/unicode-escape-spans.rs:14:23
+   |
+LL |     format!("\u{211d}{a}");
+   |                       ^ not found in this scope
+
+error[E0425]: cannot find value `a` in this scope
+  --> $DIR/unicode-escape-spans.rs:17:24
+   |
+LL |     format!("\u{1f4a3}{a}");
+   |                        ^ not found in this scope
+
+error[E0425]: cannot find value `a` in this scope
+  --> $DIR/unicode-escape-spans.rs:18:25
+   |
+LL |     format!("\u{10ffff}{a}");
+   |                         ^ not found in this scope
+
+error: aborting due to 10 previous errors
+
+For more information about this error, try `rustc --explain E0425`.
diff --git a/src/test/ui/for-loop-while/break-outside-loop.stderr b/src/test/ui/for-loop-while/break-outside-loop.stderr
index 287bf9af62e4..9092f34df354 100644
--- a/src/test/ui/for-loop-while/break-outside-loop.stderr
+++ b/src/test/ui/for-loop-while/break-outside-loop.stderr
@@ -9,11 +9,11 @@ LL |             break 'lab;
    |
    = note: labels are unreachable through functions, closures, async blocks and modules
 
-error[E0268]: `break` outside of a loop
+error[E0268]: `break` outside of a loop or labeled block
   --> $DIR/break-outside-loop.rs:10:15
    |
 LL |     let pth = break;
-   |               ^^^^^ cannot `break` outside of a loop
+   |               ^^^^^ cannot `break` outside of a loop or labeled block
 
 error[E0268]: `continue` outside of a loop
   --> $DIR/break-outside-loop.rs:11:17
@@ -38,11 +38,11 @@ LL |             if cond() { break }
 LL |             if cond() { continue }
    |                         ^^^^^^^^ cannot `continue` inside of a closure
 
-error[E0268]: `break` outside of a loop
+error[E0268]: `break` outside of a loop or labeled block
   --> $DIR/break-outside-loop.rs:24:25
    |
 LL |     let unconstrained = break;
-   |                         ^^^^^ cannot `break` outside of a loop
+   |                         ^^^^^ cannot `break` outside of a loop or labeled block
 
 error[E0267]: `break` inside of a closure
   --> $DIR/break-outside-loop.rs:30:13
diff --git a/src/test/ui/function-pointer/unsized-ret.rs b/src/test/ui/function-pointer/unsized-ret.rs
index 60af5769d6dd..79009c5cb6c0 100644
--- a/src/test/ui/function-pointer/unsized-ret.rs
+++ b/src/test/ui/function-pointer/unsized-ret.rs
@@ -1,7 +1,8 @@
 #![feature(fn_traits)]
 #![feature(unboxed_closures)]
+#![feature(tuple_trait)]
 
-fn foo<F: Fn<T>, T>(f: Option<F>, t: T) {
+fn foo<F: Fn<T>, T:std::marker::Tuple>(f: Option<F>, t: T) {
     let y = (f.unwrap()).call(t);
 }
 
diff --git a/src/test/ui/function-pointer/unsized-ret.stderr b/src/test/ui/function-pointer/unsized-ret.stderr
index bec3e2aa3fe6..40bf7a3898ac 100644
--- a/src/test/ui/function-pointer/unsized-ret.stderr
+++ b/src/test/ui/function-pointer/unsized-ret.stderr
@@ -1,5 +1,5 @@
 error[E0277]: the size for values of type `str` cannot be known at compilation time
-  --> $DIR/unsized-ret.rs:9:27
+  --> $DIR/unsized-ret.rs:10:27
    |
 LL |     foo::<fn() -> str, _>(None, ());
    |     --------------------- ^^^^ doesn't have a size known at compile-time
@@ -9,13 +9,13 @@ LL |     foo::<fn() -> str, _>(None, ());
    = help: within `fn() -> str`, the trait `Sized` is not implemented for `str`
    = note: required because it appears within the type `fn() -> str`
 note: required by a bound in `foo`
-  --> $DIR/unsized-ret.rs:4:11
+  --> $DIR/unsized-ret.rs:5:11
    |
-LL | fn foo<F: Fn<T>, T>(f: Option<F>, t: T) {
+LL | fn foo<F: Fn<T>, T:std::marker::Tuple>(f: Option<F>, t: T) {
    |           ^^^^^ required by this bound in `foo`
 
 error[E0277]: the size for values of type `(dyn std::fmt::Display + 'a)` cannot be known at compilation time
-  --> $DIR/unsized-ret.rs:12:66
+  --> $DIR/unsized-ret.rs:13:66
    |
 LL |     foo::<for<'a> fn(&'a ()) -> (dyn std::fmt::Display + 'a), _>(None, (&(),));
    |     ------------------------------------------------------------ ^^^^ doesn't have a size known at compile-time
@@ -25,9 +25,9 @@ LL |     foo::<for<'a> fn(&'a ()) -> (dyn std::fmt::Display + 'a), _>(None, (&()
    = help: within `for<'a> fn(&'a ()) -> (dyn std::fmt::Display + 'a)`, the trait `for<'a> Sized` is not implemented for `(dyn std::fmt::Display + 'a)`
    = note: required because it appears within the type `for<'a> fn(&'a ()) -> (dyn std::fmt::Display + 'a)`
 note: required by a bound in `foo`
-  --> $DIR/unsized-ret.rs:4:11
+  --> $DIR/unsized-ret.rs:5:11
    |
-LL | fn foo<F: Fn<T>, T>(f: Option<F>, t: T) {
+LL | fn foo<F: Fn<T>, T:std::marker::Tuple>(f: Option<F>, t: T) {
    |           ^^^^^ required by this bound in `foo`
 
 error: aborting due to 2 previous errors
diff --git a/src/test/ui/generator/auto-trait-regions.stderr b/src/test/ui/generator/auto-trait-regions.stderr
index 23324af6171a..0b1f34aeb96b 100644
--- a/src/test/ui/generator/auto-trait-regions.stderr
+++ b/src/test/ui/generator/auto-trait-regions.stderr
@@ -4,7 +4,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |         let a = A(&mut true, &mut true, No);
    |                        ^^^^                - temporary value is freed at the end of this statement
    |                        |
-   |                        creates a temporary which is freed while still in use
+   |                        creates a temporary value which is freed while still in use
 ...
 LL |         assert_foo(a);
    |                    - borrow later used here
@@ -17,7 +17,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |         let a = A(&mut true, &mut true, No);
    |                                   ^^^^     - temporary value is freed at the end of this statement
    |                                   |
-   |                                   creates a temporary which is freed while still in use
+   |                                   creates a temporary value which is freed while still in use
 ...
 LL |         assert_foo(a);
    |                    - borrow later used here
diff --git a/src/test/ui/generator/issue-52398.stderr b/src/test/ui/generator/issue-52398.stderr
index 30a6732f7595..539343275df6 100644
--- a/src/test/ui/generator/issue-52398.stderr
+++ b/src/test/ui/generator/issue-52398.stderr
@@ -4,7 +4,7 @@ warning: unused generator that must be used
 LL | /     move || {
 LL | |         A.test(yield);
 LL | |     };
-   | |______^
+   | |_____^
    |
    = note: generators are lazy and do nothing unless resumed
    = note: `#[warn(unused_must_use)]` on by default
@@ -16,7 +16,7 @@ LL | /     static move || {
 LL | |         yield *y.borrow();
 LL | |         return "Done";
 LL | |     };
-   | |______^
+   | |_____^
    |
    = note: generators are lazy and do nothing unless resumed
 
diff --git a/src/test/ui/generator/issue-57084.stderr b/src/test/ui/generator/issue-57084.stderr
index 29aca94408a8..8f1fc5e80319 100644
--- a/src/test/ui/generator/issue-57084.stderr
+++ b/src/test/ui/generator/issue-57084.stderr
@@ -7,7 +7,7 @@ LL | |         loop {
 LL | |             yield
 LL | |         }
 LL | |     };
-   | |______^
+   | |_____^
    |
    = note: generators are lazy and do nothing unless resumed
    = note: `#[warn(unused_must_use)]` on by default
diff --git a/src/test/ui/generator/match-bindings.stderr b/src/test/ui/generator/match-bindings.stderr
index b911b6661909..3dd2d595445a 100644
--- a/src/test/ui/generator/match-bindings.stderr
+++ b/src/test/ui/generator/match-bindings.stderr
@@ -8,7 +8,7 @@ LL | |                 match Enum::A(String::new()) {
 ...  |
 LL | |         }
 LL | |     };
-   | |______^
+   | |_____^
    |
    = note: generators are lazy and do nothing unless resumed
    = note: `#[warn(unused_must_use)]` on by default
diff --git a/src/test/ui/generator/reborrow-mut-upvar.stderr b/src/test/ui/generator/reborrow-mut-upvar.stderr
index e83dbf833bfa..2e1fec35eaf5 100644
--- a/src/test/ui/generator/reborrow-mut-upvar.stderr
+++ b/src/test/ui/generator/reborrow-mut-upvar.stderr
@@ -8,7 +8,7 @@ LL | |             yield;
 ...  |
 LL | |         *bar = 2;
 LL | |     };
-   | |______^
+   | |_____^
    |
    = note: generators are lazy and do nothing unless resumed
    = note: `#[warn(unused_must_use)]` on by default
diff --git a/src/test/ui/generator/too-live-local-in-immovable-gen.stderr b/src/test/ui/generator/too-live-local-in-immovable-gen.stderr
index 5cb43067fee6..e262f213f63d 100644
--- a/src/test/ui/generator/too-live-local-in-immovable-gen.stderr
+++ b/src/test/ui/generator/too-live-local-in-immovable-gen.stderr
@@ -8,7 +8,7 @@ LL | |             // and it should also find out that `a` is not live.
 ...  |
 LL | |             let _ = &a;
 LL | |         };
-   | |__________^
+   | |_________^
    |
    = note: generators are lazy and do nothing unless resumed
    = note: `#[warn(unused_must_use)]` on by default
diff --git a/src/test/ui/generator/yield-in-args-rev.stderr b/src/test/ui/generator/yield-in-args-rev.stderr
index c9e1ab722d47..a87248f66210 100644
--- a/src/test/ui/generator/yield-in-args-rev.stderr
+++ b/src/test/ui/generator/yield-in-args-rev.stderr
@@ -5,7 +5,7 @@ LL | /     || {
 LL | |         let b = true;
 LL | |         foo(yield, &b);
 LL | |     };
-   | |______^
+   | |_____^
    |
    = note: generators are lazy and do nothing unless resumed
    = note: `#[warn(unused_must_use)]` on by default
diff --git a/src/test/ui/generator/yield-in-box.stderr b/src/test/ui/generator/yield-in-box.stderr
index 8587e1dc663b..9d03ee00800c 100644
--- a/src/test/ui/generator/yield-in-box.stderr
+++ b/src/test/ui/generator/yield-in-box.stderr
@@ -8,7 +8,7 @@ LL | |             let _t = box (&x, yield 0, &y);
 ...  |
 LL | |         }
 LL | |     };
-   | |______^
+   | |_____^
    |
    = note: generators are lazy and do nothing unless resumed
    = note: `#[warn(unused_must_use)]` on by default
diff --git a/src/test/ui/generator/yield-in-initializer.stderr b/src/test/ui/generator/yield-in-initializer.stderr
index 07de24662cf2..ed14a2e3273a 100644
--- a/src/test/ui/generator/yield-in-initializer.stderr
+++ b/src/test/ui/generator/yield-in-initializer.stderr
@@ -8,7 +8,7 @@ LL | |             // See https://github.com/rust-lang/rust/issues/52792
 ...  |
 LL | |         }
 LL | |     };
-   | |______^
+   | |_____^
    |
    = note: generators are lazy and do nothing unless resumed
    = note: `#[warn(unused_must_use)]` on by default
diff --git a/src/test/ui/generator/yield-subtype.stderr b/src/test/ui/generator/yield-subtype.stderr
index fe10477bf738..97862e91cd4a 100644
--- a/src/test/ui/generator/yield-subtype.stderr
+++ b/src/test/ui/generator/yield-subtype.stderr
@@ -5,7 +5,7 @@ LL | /     || {
 LL | |         yield a;
 LL | |         yield b;
 LL | |     };
-   | |______^
+   | |_____^
    |
    = note: generators are lazy and do nothing unless resumed
    = note: `#[warn(unused_must_use)]` on by default
diff --git a/src/test/ui/generic-associated-types/bugs/hrtb-implied-1.stderr b/src/test/ui/generic-associated-types/bugs/hrtb-implied-1.stderr
index 414999881d47..1c9abc4e837c 100644
--- a/src/test/ui/generic-associated-types/bugs/hrtb-implied-1.stderr
+++ b/src/test/ui/generic-associated-types/bugs/hrtb-implied-1.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/hrtb-implied-1.rs:31:22
    |
 LL |     let slice = &mut ();
-   |                      ^^ creates a temporary which is freed while still in use
+   |                      ^^ creates a temporary value which is freed while still in use
 ...
 LL |     print_items::<WindowsMut<'_>>(windows);
    |     -------------------------------------- argument requires that borrow lasts for `'static`
diff --git a/src/test/ui/generic-associated-types/bugs/issue-100013.rs b/src/test/ui/generic-associated-types/bugs/issue-100013.rs
new file mode 100644
index 000000000000..fc4e47a3ba18
--- /dev/null
+++ b/src/test/ui/generic-associated-types/bugs/issue-100013.rs
@@ -0,0 +1,39 @@
+// check-fail
+// known-bug
+// edition: 2021
+
+// We really should accept this, but we need implied bounds between the regions
+// in a generator interior.
+
+pub trait FutureIterator {
+    type Future<'s, 'cx>: Send
+    where
+        's: 'cx;
+}
+
+fn call<I: FutureIterator>() -> impl Send {
+    async { // a generator checked for autotrait impl `Send`
+        //~^ lifetime bound not satisfied
+        let x = None::<I::Future<'_, '_>>; // a type referencing GAT
+        async {}.await; // a yield point
+    }
+}
+
+fn call2<'a, 'b, I: FutureIterator>() -> impl Send {
+    async { // a generator checked for autotrait impl `Send`
+        //~^ lifetime bound not satisfied
+        let x = None::<I::Future<'a, 'b>>; // a type referencing GAT
+        //~^ lifetime may not live long enough
+        async {}.await; // a yield point
+    }
+}
+
+fn call3<'a: 'b, 'b, I: FutureIterator>() -> impl Send {
+    async { // a generator checked for autotrait impl `Send`
+        //~^ lifetime bound not satisfied
+        let x = None::<I::Future<'a, 'b>>; // a type referencing GAT
+        async {}.await; // a yield point
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/generic-associated-types/bugs/issue-100013.stderr b/src/test/ui/generic-associated-types/bugs/issue-100013.stderr
new file mode 100644
index 000000000000..72ae288dcab6
--- /dev/null
+++ b/src/test/ui/generic-associated-types/bugs/issue-100013.stderr
@@ -0,0 +1,82 @@
+error: lifetime bound not satisfied
+  --> $DIR/issue-100013.rs:15:5
+   |
+LL | /     async { // a generator checked for autotrait impl `Send`
+LL | |
+LL | |         let x = None::<I::Future<'_, '_>>; // a type referencing GAT
+LL | |         async {}.await; // a yield point
+LL | |     }
+   | |_____^
+   |
+note: the lifetime defined here...
+  --> $DIR/issue-100013.rs:17:38
+   |
+LL |         let x = None::<I::Future<'_, '_>>; // a type referencing GAT
+   |                                      ^^
+note: ...must outlive the lifetime defined here
+  --> $DIR/issue-100013.rs:17:34
+   |
+LL |         let x = None::<I::Future<'_, '_>>; // a type referencing GAT
+   |                                  ^^
+   = note: this is a known limitation that will be removed in the future (see issue #100013 <https://github.com/rust-lang/rust/issues/100013> for more information)
+
+error: lifetime bound not satisfied
+  --> $DIR/issue-100013.rs:23:5
+   |
+LL | /     async { // a generator checked for autotrait impl `Send`
+LL | |
+LL | |         let x = None::<I::Future<'a, 'b>>; // a type referencing GAT
+LL | |
+LL | |         async {}.await; // a yield point
+LL | |     }
+   | |_____^
+   |
+note: the lifetime defined here...
+  --> $DIR/issue-100013.rs:22:14
+   |
+LL | fn call2<'a, 'b, I: FutureIterator>() -> impl Send {
+   |              ^^
+note: ...must outlive the lifetime defined here
+  --> $DIR/issue-100013.rs:22:10
+   |
+LL | fn call2<'a, 'b, I: FutureIterator>() -> impl Send {
+   |          ^^
+   = note: this is a known limitation that will be removed in the future (see issue #100013 <https://github.com/rust-lang/rust/issues/100013> for more information)
+
+error: lifetime may not live long enough
+  --> $DIR/issue-100013.rs:25:17
+   |
+LL | fn call2<'a, 'b, I: FutureIterator>() -> impl Send {
+   |          --  -- lifetime `'b` defined here
+   |          |
+   |          lifetime `'a` defined here
+...
+LL |         let x = None::<I::Future<'a, 'b>>; // a type referencing GAT
+   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^ requires that `'a` must outlive `'b`
+   |
+   = help: consider adding the following bound: `'a: 'b`
+
+error: lifetime bound not satisfied
+  --> $DIR/issue-100013.rs:32:5
+   |
+LL | /     async { // a generator checked for autotrait impl `Send`
+LL | |
+LL | |         let x = None::<I::Future<'a, 'b>>; // a type referencing GAT
+LL | |         async {}.await; // a yield point
+LL | |     }
+   | |_____^
+   |
+note: the lifetime defined here...
+  --> $DIR/issue-100013.rs:31:18
+   |
+LL | fn call3<'a: 'b, 'b, I: FutureIterator>() -> impl Send {
+   |                  ^^
+note: ...must outlive the lifetime defined here
+  --> $DIR/issue-100013.rs:31:10
+   |
+LL | fn call3<'a: 'b, 'b, I: FutureIterator>() -> impl Send {
+   |          ^^
+   = note: this is a known limitation that will be removed in the future (see issue #100013 <https://github.com/rust-lang/rust/issues/100013> for more information)
+
+error: aborting due to 4 previous errors
+
diff --git a/src/test/ui/generic-associated-types/bugs/issue-80626.rs b/src/test/ui/generic-associated-types/bugs/issue-80626.rs
index f6aa6b36e13d..d6e18010f3b2 100644
--- a/src/test/ui/generic-associated-types/bugs/issue-80626.rs
+++ b/src/test/ui/generic-associated-types/bugs/issue-80626.rs
@@ -1,7 +1,4 @@
-// check-fail
-// known-bug: #80626
-
-// This should pass, but it requires `Sized` to be coinductive.
+// check-pass
 
 trait Allocator {
     type Allocated<T>;
@@ -9,7 +6,7 @@ trait Allocator {
 
 enum LinkedList<A: Allocator> {
     Head,
-    Next(A::Allocated<Self>)
+    Next(A::Allocated<Self>),
 }
 
 fn main() {}
diff --git a/src/test/ui/generic-associated-types/bugs/issue-80626.stderr b/src/test/ui/generic-associated-types/bugs/issue-80626.stderr
deleted file mode 100644
index 9a0f332ed473..000000000000
--- a/src/test/ui/generic-associated-types/bugs/issue-80626.stderr
+++ /dev/null
@@ -1,15 +0,0 @@
-error[E0275]: overflow evaluating the requirement `LinkedList<A>: Sized`
-  --> $DIR/issue-80626.rs:12:10
-   |
-LL |     Next(A::Allocated<Self>)
-   |          ^^^^^^^^^^^^^^^^^^
-   |
-note: required by a bound in `Allocator::Allocated`
-  --> $DIR/issue-80626.rs:7:20
-   |
-LL |     type Allocated<T>;
-   |                    ^ required by this bound in `Allocator::Allocated`
-
-error: aborting due to previous error
-
-For more information about this error, try `rustc --explain E0275`.
diff --git a/src/test/ui/generic-associated-types/issue-87258_a.stderr b/src/test/ui/generic-associated-types/issue-87258_a.stderr
index fa0748a280b6..eae9bd9b16f2 100644
--- a/src/test/ui/generic-associated-types/issue-87258_a.stderr
+++ b/src/test/ui/generic-associated-types/issue-87258_a.stderr
@@ -4,7 +4,7 @@ error: unconstrained opaque type
 LL |     type FooFuture<'a> = impl Trait1;
    |                          ^^^^^^^^^^^
    |
-   = note: `FooFuture` must be used in combination with a concrete type within the same module
+   = note: `FooFuture` must be used in combination with a concrete type within the same impl
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/generic-associated-types/issue-87750.rs b/src/test/ui/generic-associated-types/issue-87750.rs
index 0a11a0f3ae0e..b35657989efb 100644
--- a/src/test/ui/generic-associated-types/issue-87750.rs
+++ b/src/test/ui/generic-associated-types/issue-87750.rs
@@ -1,3 +1,5 @@
+// check-pass
+
 trait PointerFamily {
     type Pointer<T>;
 }
@@ -10,11 +12,13 @@ impl PointerFamily for RcFamily {
 }
 
 #[allow(dead_code)]
-enum Node<T, P: PointerFamily> where P::Pointer<Node<T, P>>: Sized {
+enum Node<T, P: PointerFamily>
+where
+    P::Pointer<Node<T, P>>: Sized,
+{
     Cons(P::Pointer<Node<T, P>>),
 }
 
 fn main() {
     let _list: <RcFamily as PointerFamily>::Pointer<Node<i32, RcFamily>>;
-    //~^ ERROR overflow evaluating the requirement `Node<i32, RcFamily>: Sized`
 }
diff --git a/src/test/ui/generic-associated-types/issue-87750.stderr b/src/test/ui/generic-associated-types/issue-87750.stderr
deleted file mode 100644
index b358ca273ca7..000000000000
--- a/src/test/ui/generic-associated-types/issue-87750.stderr
+++ /dev/null
@@ -1,9 +0,0 @@
-error[E0275]: overflow evaluating the requirement `Node<i32, RcFamily>: Sized`
-  --> $DIR/issue-87750.rs:18:16
-   |
-LL |     let _list: <RcFamily as PointerFamily>::Pointer<Node<i32, RcFamily>>;
-   |                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-error: aborting due to previous error
-
-For more information about this error, try `rustc --explain E0275`.
diff --git a/src/test/ui/generic-associated-types/issue-91139.rs b/src/test/ui/generic-associated-types/issue-91139.rs
index 5fc6071c9396..e321da53d566 100644
--- a/src/test/ui/generic-associated-types/issue-91139.rs
+++ b/src/test/ui/generic-associated-types/issue-91139.rs
@@ -21,6 +21,7 @@ fn foo<T>() {
     //~| ERROR `T` does not live long enough
     //~| ERROR `T` does not live long enough
     //~| ERROR `T` may not live long enough
+    //~| ERROR `T` may not live long enough
     //
     // FIXME: This error is bogus, but it arises because we try to validate
     // that `<() as Foo<T>>::Type<'a>` is valid, which requires proving
diff --git a/src/test/ui/generic-associated-types/issue-91139.stderr b/src/test/ui/generic-associated-types/issue-91139.stderr
index 8bbe98fa1e50..5485570cecd7 100644
--- a/src/test/ui/generic-associated-types/issue-91139.stderr
+++ b/src/test/ui/generic-associated-types/issue-91139.stderr
@@ -22,6 +22,17 @@ error: `T` does not live long enough
 LL |     let _: for<'a> fn(<() as Foo<T>>::Type<'a>, &'a T) = |_, _| ();
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
+error[E0310]: the parameter type `T` may not live long enough
+  --> $DIR/issue-91139.rs:14:58
+   |
+LL |     let _: for<'a> fn(<() as Foo<T>>::Type<'a>, &'a T) = |_, _| ();
+   |                                                          ^^^^^^ ...so that the type `T` will meet its required lifetime bounds
+   |
+help: consider adding an explicit lifetime bound...
+   |
+LL | fn foo<T: 'static>() {
+   |         +++++++++
+
 error: `T` does not live long enough
   --> $DIR/issue-91139.rs:14:58
    |
@@ -57,6 +68,6 @@ error: `T` does not live long enough
 LL |     let _: for<'a> fn(<() as Foo<T>>::Type<'a>, &'a T) = |_, _| ();
    |                                                          ^^^^^^^^^
 
-error: aborting due to 9 previous errors
+error: aborting due to 10 previous errors
 
 For more information about this error, try `rustc --explain E0310`.
diff --git a/src/test/ui/generic-associated-types/projection-bound-cycle-generic.rs b/src/test/ui/generic-associated-types/projection-bound-cycle-generic.rs
index 58d57df63c1b..ecf6f69c9fa7 100644
--- a/src/test/ui/generic-associated-types/projection-bound-cycle-generic.rs
+++ b/src/test/ui/generic-associated-types/projection-bound-cycle-generic.rs
@@ -21,6 +21,7 @@ impl<T> Foo for Number<T> {
     // ```
     // which it is :)
     type Item = [T] where [T]: Sized;
+    //~^ ERROR overflow evaluating the requirement `<Number<T> as Foo>::Item == _`
 }
 
 struct OnlySized<T> where T: Sized { f: T }
@@ -40,7 +41,6 @@ impl<T> Bar for T where T: Foo {
     // can use the bound on `Foo::Item` for this, but that requires
     // `wf(<T as Foo>::Item)`, which is an invalid cycle.
     type Assoc = OnlySized<<T as Foo>::Item>;
-    //~^ ERROR overflow evaluating the requirement `<T as Foo>::Item: Sized`
 }
 
 fn foo<T: Print>() {
diff --git a/src/test/ui/generic-associated-types/projection-bound-cycle-generic.stderr b/src/test/ui/generic-associated-types/projection-bound-cycle-generic.stderr
index 27c1a82994a5..aae9a56bb612 100644
--- a/src/test/ui/generic-associated-types/projection-bound-cycle-generic.stderr
+++ b/src/test/ui/generic-associated-types/projection-bound-cycle-generic.stderr
@@ -1,14 +1,8 @@
-error[E0275]: overflow evaluating the requirement `<T as Foo>::Item: Sized`
-  --> $DIR/projection-bound-cycle-generic.rs:42:18
+error[E0275]: overflow evaluating the requirement `<Number<T> as Foo>::Item == _`
+  --> $DIR/projection-bound-cycle-generic.rs:23:5
    |
-LL |     type Assoc = OnlySized<<T as Foo>::Item>;
-   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-note: required by a bound in `OnlySized`
-  --> $DIR/projection-bound-cycle-generic.rs:26:18
-   |
-LL | struct OnlySized<T> where T: Sized { f: T }
-   |                  ^ required by this bound in `OnlySized`
+LL |     type Item = [T] where [T]: Sized;
+   |     ^^^^^^^^^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/generic-associated-types/projection-bound-cycle.rs b/src/test/ui/generic-associated-types/projection-bound-cycle.rs
index 4cad1f61319e..b51ae7ef2018 100644
--- a/src/test/ui/generic-associated-types/projection-bound-cycle.rs
+++ b/src/test/ui/generic-associated-types/projection-bound-cycle.rs
@@ -24,6 +24,7 @@ impl Foo for Number {
     // ```
     // which it is :)
     type Item = str where str: Sized;
+    //~^ ERROR overflow evaluating the requirement `<Number as Foo>::Item == _`
 }
 
 struct OnlySized<T> where T: Sized { f: T }
@@ -43,7 +44,6 @@ impl<T> Bar for T where T: Foo {
     // can use the bound on `Foo::Item` for this, but that requires
     // `wf(<T as Foo>::Item)`, which is an invalid cycle.
     type Assoc = OnlySized<<T as Foo>::Item>;
-    //~^ ERROR overflow evaluating the requirement `<T as Foo>::Item: Sized`
 }
 
 fn foo<T: Print>() {
diff --git a/src/test/ui/generic-associated-types/projection-bound-cycle.stderr b/src/test/ui/generic-associated-types/projection-bound-cycle.stderr
index a46518c80da7..b1b8afeecd02 100644
--- a/src/test/ui/generic-associated-types/projection-bound-cycle.stderr
+++ b/src/test/ui/generic-associated-types/projection-bound-cycle.stderr
@@ -1,14 +1,8 @@
-error[E0275]: overflow evaluating the requirement `<T as Foo>::Item: Sized`
-  --> $DIR/projection-bound-cycle.rs:45:18
+error[E0275]: overflow evaluating the requirement `<Number as Foo>::Item == _`
+  --> $DIR/projection-bound-cycle.rs:26:5
    |
-LL |     type Assoc = OnlySized<<T as Foo>::Item>;
-   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-note: required by a bound in `OnlySized`
-  --> $DIR/projection-bound-cycle.rs:29:18
-   |
-LL | struct OnlySized<T> where T: Sized { f: T }
-   |                  ^ required by this bound in `OnlySized`
+LL |     type Item = str where str: Sized;
+   |     ^^^^^^^^^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/issues/issue-36139-normalize-closure-sig.rs b/src/test/ui/higher-rank-trait-bounds/issue-36139-normalize-closure-sig.rs
similarity index 100%
rename from src/test/ui/issues/issue-36139-normalize-closure-sig.rs
rename to src/test/ui/higher-rank-trait-bounds/issue-36139-normalize-closure-sig.rs
diff --git a/src/test/ui/issues/issue-43623.rs b/src/test/ui/higher-rank-trait-bounds/issue-43623.rs
similarity index 100%
rename from src/test/ui/issues/issue-43623.rs
rename to src/test/ui/higher-rank-trait-bounds/issue-43623.rs
diff --git a/src/test/ui/higher-rank-trait-bounds/normalize-under-binder/issue-90950.rs b/src/test/ui/higher-rank-trait-bounds/normalize-under-binder/issue-90950.rs
new file mode 100644
index 000000000000..ab9d9a7ce6f0
--- /dev/null
+++ b/src/test/ui/higher-rank-trait-bounds/normalize-under-binder/issue-90950.rs
@@ -0,0 +1,53 @@
+// check-fail
+// known-bug: #90950
+
+trait Yokeable<'a>: 'static {
+    type Output: 'a;
+}
+
+
+trait IsCovariant<'a> {}
+
+struct Yoke<Y: for<'a> Yokeable<'a>> {
+    data: Y,
+}
+
+
+// impl<Y: for<'a> Yokeable<'a>> Yoke<Y> {
+//     fn project<Y2: for<'a> Yokeable<'a>>(
+//         &self,
+//         f: for<'a> fn(<Y as Yokeable<'a>>::Output, &'a (),
+//     ) -> <Y2 as Yokeable<'a>>::Output) -> Yoke<Y2> {
+//         unimplemented!()
+//     }
+// }
+
+fn upcast<Y>(x: Yoke<Y>) -> Yoke<Box<dyn IsCovariant<'static> + 'static>> where
+    Y: for<'a> Yokeable<'a>,
+    for<'a> <Y as Yokeable<'a>>::Output: IsCovariant<'a>
+    {
+    // x.project(|data, _| {
+    //     Box::new(data)
+    // })
+    unimplemented!()
+}
+
+
+impl<'a> Yokeable<'a> for Box<dyn IsCovariant<'static> + 'static> {
+    type Output = Box<dyn IsCovariant<'a> + 'a>;
+}
+
+// this impl is mostly an example and unnecessary for the pure repro
+use std::borrow::*;
+impl<'a, T: ToOwned + ?Sized> Yokeable<'a> for Cow<'static, T> {
+    type Output = Cow<'a, T>;
+}
+impl<'a, T: ToOwned + ?Sized> IsCovariant<'a> for Cow<'a, T> {}
+
+
+
+fn upcast_yoke(y: Yoke<Cow<'static, str>>) -> Yoke<Box<dyn IsCovariant<'static> + 'static>> {
+    upcast(y)
+}
+
+fn main() {}
diff --git a/src/test/ui/higher-rank-trait-bounds/normalize-under-binder/issue-90950.stderr b/src/test/ui/higher-rank-trait-bounds/normalize-under-binder/issue-90950.stderr
new file mode 100644
index 000000000000..6206b167b0b8
--- /dev/null
+++ b/src/test/ui/higher-rank-trait-bounds/normalize-under-binder/issue-90950.stderr
@@ -0,0 +1,21 @@
+error[E0277]: the trait bound `for<'a> <_ as Yokeable<'a>>::Output: IsCovariant<'a>` is not satisfied
+  --> $DIR/issue-90950.rs:50:12
+   |
+LL |     upcast(y)
+   |     ------ ^ the trait `for<'a> IsCovariant<'a>` is not implemented for `<_ as Yokeable<'a>>::Output`
+   |     |
+   |     required by a bound introduced by this call
+   |
+   = help: the trait `IsCovariant<'a>` is implemented for `std::borrow::Cow<'a, T>`
+note: required by a bound in `upcast`
+  --> $DIR/issue-90950.rs:27:42
+   |
+LL | fn upcast<Y>(x: Yoke<Y>) -> Yoke<Box<dyn IsCovariant<'static> + 'static>> where
+   |    ------ required by a bound in this
+LL |     Y: for<'a> Yokeable<'a>,
+LL |     for<'a> <Y as Yokeable<'a>>::Output: IsCovariant<'a>
+   |                                          ^^^^^^^^^^^^^^^ required by this bound in `upcast`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0277`.
diff --git a/src/test/ui/higher-rank-trait-bounds/normalize-under-binder/norm-before-method-resolution.rs b/src/test/ui/higher-rank-trait-bounds/normalize-under-binder/norm-before-method-resolution.rs
new file mode 100644
index 000000000000..7693b1182476
--- /dev/null
+++ b/src/test/ui/higher-rank-trait-bounds/normalize-under-binder/norm-before-method-resolution.rs
@@ -0,0 +1,23 @@
+// check-fail
+// known-bug: #89196
+
+// Should pass, but we normalize and check bounds before we resolve the generics
+// of the function (which we know because of the return type).
+
+trait Trait<'a> {
+    type Out;
+}
+
+impl<'a, T> Trait<'a> for T {
+    type Out = T;
+}
+
+fn weird_bound<X>() -> X
+    where
+        for<'a> X: Trait<'a>,
+        for<'a> <X as Trait<'a>>::Out: Copy
+{ todo!() }
+
+fn main() {
+    let _: () = weird_bound();
+}
diff --git a/src/test/ui/higher-rank-trait-bounds/normalize-under-binder/norm-before-method-resolution.stderr b/src/test/ui/higher-rank-trait-bounds/normalize-under-binder/norm-before-method-resolution.stderr
new file mode 100644
index 000000000000..51c9646004af
--- /dev/null
+++ b/src/test/ui/higher-rank-trait-bounds/normalize-under-binder/norm-before-method-resolution.stderr
@@ -0,0 +1,18 @@
+error[E0277]: the trait bound `for<'a> <_ as Trait<'a>>::Out: Copy` is not satisfied
+  --> $DIR/norm-before-method-resolution.rs:22:17
+   |
+LL |     let _: () = weird_bound();
+   |                 ^^^^^^^^^^^ the trait `for<'a> Copy` is not implemented for `<_ as Trait<'a>>::Out`
+   |
+note: required by a bound in `weird_bound`
+  --> $DIR/norm-before-method-resolution.rs:18:40
+   |
+LL | fn weird_bound<X>() -> X
+   |    ----------- required by a bound in this
+...
+LL |         for<'a> <X as Trait<'a>>::Out: Copy
+   |                                        ^^^^ required by this bound in `weird_bound`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0277`.
diff --git a/src/test/ui/hygiene/no_implicit_prelude.stderr b/src/test/ui/hygiene/no_implicit_prelude.stderr
index 0f2ff96b5edb..c48c840352fa 100644
--- a/src/test/ui/hygiene/no_implicit_prelude.stderr
+++ b/src/test/ui/hygiene/no_implicit_prelude.stderr
@@ -5,7 +5,7 @@ LL |     fn f() { ::bar::m!(); }
    |              ----------- in this macro invocation
 ...
 LL |         Vec::new();
-   |         ^^^ not found in this scope
+   |         ^^^ use of undeclared type `Vec`
    |
    = note: this error originates in the macro `::bar::m` (in Nightly builds, run with -Z macro-backtrace for more info)
 help: consider importing this struct
diff --git a/src/test/ui/impl-trait/cross-return-site-inference.rs b/src/test/ui/impl-trait/cross-return-site-inference.rs
index d881af9ed8fe..00aed2ad95a2 100644
--- a/src/test/ui/impl-trait/cross-return-site-inference.rs
+++ b/src/test/ui/impl-trait/cross-return-site-inference.rs
@@ -30,16 +30,19 @@ fn baa(b: bool) -> impl std::fmt::Debug {
 
 fn muh() -> Result<(), impl std::fmt::Debug> {
     Err("whoops")?;
-    Ok(()) //~ ERROR type annotations needed
+    Ok(())
+    //~^ ERROR type annotations needed
 }
 
 fn muh2() -> Result<(), impl std::fmt::Debug> {
-    return Err(From::from("foo")); //~ ERROR type annotations needed
+    return Err(From::from("foo"));
+    //~^ ERROR type annotations needed
     Ok(())
 }
 
 fn muh3() -> Result<(), impl std::fmt::Debug> {
-    Err(From::from("foo")) //~ ERROR type annotations needed
+    Err(From::from("foo"))
+    //~^ ERROR type annotations needed
 }
 
 fn main() {}
diff --git a/src/test/ui/impl-trait/cross-return-site-inference.stderr b/src/test/ui/impl-trait/cross-return-site-inference.stderr
index 1ff777e65037..766614e9e50f 100644
--- a/src/test/ui/impl-trait/cross-return-site-inference.stderr
+++ b/src/test/ui/impl-trait/cross-return-site-inference.stderr
@@ -10,7 +10,7 @@ LL |     Ok::<(), E>(())
    |       +++++++++
 
 error[E0282]: type annotations needed
-  --> $DIR/cross-return-site-inference.rs:37:12
+  --> $DIR/cross-return-site-inference.rs:38:12
    |
 LL |     return Err(From::from("foo"));
    |            ^^^ cannot infer type of the type parameter `E` declared on the enum `Result`
@@ -21,7 +21,7 @@ LL |     return Err::<(), E>(From::from("foo"));
    |               +++++++++
 
 error[E0282]: type annotations needed
-  --> $DIR/cross-return-site-inference.rs:42:5
+  --> $DIR/cross-return-site-inference.rs:44:5
    |
 LL |     Err(From::from("foo"))
    |     ^^^ cannot infer type of the type parameter `E` declared on the enum `Result`
diff --git a/src/test/ui/impl-trait/deduce-signature-from-supertrait.rs b/src/test/ui/impl-trait/deduce-signature-from-supertrait.rs
new file mode 100644
index 000000000000..d2c347920357
--- /dev/null
+++ b/src/test/ui/impl-trait/deduce-signature-from-supertrait.rs
@@ -0,0 +1,15 @@
+// check-pass
+
+#![feature(type_alias_impl_trait)]
+
+trait SuperExpectation: Fn(i32) {}
+
+impl<T: Fn(i32)> SuperExpectation for T {}
+
+type Foo = impl SuperExpectation;
+
+fn main() {
+    let _: Foo = |x| {
+        let _ = x.to_string();
+    };
+}
diff --git a/src/test/ui/impl-trait/generic-with-implicit-hrtb-without-dyn.edition2021.stderr b/src/test/ui/impl-trait/generic-with-implicit-hrtb-without-dyn.edition2021.stderr
index 88e2520bf4b2..30fbba168689 100644
--- a/src/test/ui/impl-trait/generic-with-implicit-hrtb-without-dyn.edition2021.stderr
+++ b/src/test/ui/impl-trait/generic-with-implicit-hrtb-without-dyn.edition2021.stderr
@@ -9,13 +9,6 @@ help: add `dyn` keyword before this trait
 LL | fn ice() -> impl AsRef<dyn Fn(&())> {
    |                        +++
 
-error[E0277]: the trait bound `(): AsRef<(dyn for<'a> Fn(&'a ()) + 'static)>` is not satisfied
-  --> $DIR/generic-with-implicit-hrtb-without-dyn.rs:6:13
-   |
-LL | fn ice() -> impl AsRef<Fn(&())> {
-   |             ^^^^^^^^^^^^^^^^^^^ the trait `AsRef<(dyn for<'a> Fn(&'a ()) + 'static)>` is not implemented for `()`
+error: aborting due to previous error
 
-error: aborting due to 2 previous errors
-
-Some errors have detailed explanations: E0277, E0782.
-For more information about an error, try `rustc --explain E0277`.
+For more information about this error, try `rustc --explain E0782`.
diff --git a/src/test/ui/impl-trait/generic-with-implicit-hrtb-without-dyn.rs b/src/test/ui/impl-trait/generic-with-implicit-hrtb-without-dyn.rs
index 5a922697f6ff..bed81c4bca76 100644
--- a/src/test/ui/impl-trait/generic-with-implicit-hrtb-without-dyn.rs
+++ b/src/test/ui/impl-trait/generic-with-implicit-hrtb-without-dyn.rs
@@ -4,8 +4,8 @@
 #![allow(warnings)]
 
 fn ice() -> impl AsRef<Fn(&())> {
-    //~^ ERROR: the trait bound `(): AsRef<(dyn for<'a> Fn(&'a ()) + 'static)>` is not satisfied [E0277]
-    //[edition2021]~| ERROR: trait objects must include the `dyn` keyword [E0782]
+    //[edition2015]~^ ERROR: the trait bound `(): AsRef<(dyn for<'a> Fn(&'a ()) + 'static)>` is not satisfied [E0277]
+    //[edition2021]~^^ ERROR: trait objects must include the `dyn` keyword [E0782]
     todo!()
 }
 
diff --git a/src/test/ui/impl-trait/hidden-lifetimes.stderr b/src/test/ui/impl-trait/hidden-lifetimes.stderr
index de06ded7acdb..3cc47e1e89da 100644
--- a/src/test/ui/impl-trait/hidden-lifetimes.stderr
+++ b/src/test/ui/impl-trait/hidden-lifetimes.stderr
@@ -6,7 +6,7 @@ LL | fn hide_ref<'a, 'b, T: 'static>(x: &'a mut &'b T) -> impl Swap + 'a {
 LL |     x
    |     ^
    |
-help: to declare that the `impl Trait` captures `'b`, you can add an explicit `'b` lifetime bound
+help: to declare that `impl Swap + 'a` captures `'b`, you can add an explicit `'b` lifetime bound
    |
 LL | fn hide_ref<'a, 'b, T: 'static>(x: &'a mut &'b T) -> impl Swap + 'a + 'b {
    |                                                                     ++++
@@ -19,7 +19,7 @@ LL | fn hide_rc_refcell<'a, 'b: 'a, T: 'static>(x: Rc<RefCell<&'b T>>) -> impl S
 LL |     x
    |     ^
    |
-help: to declare that the `impl Trait` captures `'b`, you can add an explicit `'b` lifetime bound
+help: to declare that `impl Swap + 'a` captures `'b`, you can add an explicit `'b` lifetime bound
    |
 LL | fn hide_rc_refcell<'a, 'b: 'a, T: 'static>(x: Rc<RefCell<&'b T>>) -> impl Swap + 'a + 'b {
    |                                                                                     ++++
diff --git a/src/test/ui/impl-trait/impl-fn-hrtb-bounds-2.rs b/src/test/ui/impl-trait/impl-fn-hrtb-bounds-2.rs
new file mode 100644
index 000000000000..b0aeded0ef75
--- /dev/null
+++ b/src/test/ui/impl-trait/impl-fn-hrtb-bounds-2.rs
@@ -0,0 +1,8 @@
+#![feature(impl_trait_in_fn_trait_return)]
+use std::fmt::Debug;
+
+fn a() -> impl Fn(&u8) -> impl Debug {
+    |x| x //~ ERROR hidden type for `impl Debug` captures lifetime that does not appear in bounds
+}
+
+fn main() {}
diff --git a/src/test/ui/impl-trait/impl-fn-hrtb-bounds-2.stderr b/src/test/ui/impl-trait/impl-fn-hrtb-bounds-2.stderr
new file mode 100644
index 000000000000..433b76b7afaa
--- /dev/null
+++ b/src/test/ui/impl-trait/impl-fn-hrtb-bounds-2.stderr
@@ -0,0 +1,11 @@
+error[E0700]: hidden type for `impl Debug` captures lifetime that does not appear in bounds
+  --> $DIR/impl-fn-hrtb-bounds-2.rs:5:9
+   |
+LL |     |x| x
+   |     --- ^
+   |     |
+   |     hidden type `&u8` captures the anonymous lifetime #1 defined here
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0700`.
diff --git a/src/test/ui/impl-trait/impl-fn-hrtb-bounds.rs b/src/test/ui/impl-trait/impl-fn-hrtb-bounds.rs
new file mode 100644
index 000000000000..527a4586fd7e
--- /dev/null
+++ b/src/test/ui/impl-trait/impl-fn-hrtb-bounds.rs
@@ -0,0 +1,24 @@
+#![feature(impl_trait_in_fn_trait_return)]
+use std::fmt::Debug;
+
+fn a() -> impl Fn(&u8) -> (impl Debug + '_) {
+    //~^ ERROR higher kinded lifetime bounds on nested opaque types are not supported yet
+    |x| x
+}
+
+fn b() -> impl for<'a> Fn(&'a u8) -> (impl Debug + 'a) {
+    //~^ ERROR higher kinded lifetime bounds on nested opaque types are not supported yet
+    |x| x
+}
+
+fn c() -> impl for<'a> Fn(&'a u8) -> (impl Debug + '_) {
+    //~^ ERROR higher kinded lifetime bounds on nested opaque types are not supported yet
+    |x| x
+}
+
+fn d() -> impl Fn() -> (impl Debug + '_) {
+    //~^ ERROR missing lifetime specifier
+    || ()
+}
+
+fn main() {}
diff --git a/src/test/ui/impl-trait/impl-fn-hrtb-bounds.stderr b/src/test/ui/impl-trait/impl-fn-hrtb-bounds.stderr
new file mode 100644
index 000000000000..443ffeb55cde
--- /dev/null
+++ b/src/test/ui/impl-trait/impl-fn-hrtb-bounds.stderr
@@ -0,0 +1,51 @@
+error[E0106]: missing lifetime specifier
+  --> $DIR/impl-fn-hrtb-bounds.rs:19:38
+   |
+LL | fn d() -> impl Fn() -> (impl Debug + '_) {
+   |                                      ^^ expected named lifetime parameter
+   |
+   = help: this function's return type contains a borrowed value, but there is no value for it to be borrowed from
+help: consider using the `'static` lifetime
+   |
+LL | fn d() -> impl Fn() -> (impl Debug + 'static) {
+   |                                      ~~~~~~~
+
+error: higher kinded lifetime bounds on nested opaque types are not supported yet
+  --> $DIR/impl-fn-hrtb-bounds.rs:4:41
+   |
+LL | fn a() -> impl Fn(&u8) -> (impl Debug + '_) {
+   |                                         ^^
+   |
+note: lifetime declared here
+  --> $DIR/impl-fn-hrtb-bounds.rs:4:19
+   |
+LL | fn a() -> impl Fn(&u8) -> (impl Debug + '_) {
+   |                   ^
+
+error: higher kinded lifetime bounds on nested opaque types are not supported yet
+  --> $DIR/impl-fn-hrtb-bounds.rs:9:52
+   |
+LL | fn b() -> impl for<'a> Fn(&'a u8) -> (impl Debug + 'a) {
+   |                                                    ^^
+   |
+note: lifetime declared here
+  --> $DIR/impl-fn-hrtb-bounds.rs:9:20
+   |
+LL | fn b() -> impl for<'a> Fn(&'a u8) -> (impl Debug + 'a) {
+   |                    ^^
+
+error: higher kinded lifetime bounds on nested opaque types are not supported yet
+  --> $DIR/impl-fn-hrtb-bounds.rs:14:52
+   |
+LL | fn c() -> impl for<'a> Fn(&'a u8) -> (impl Debug + '_) {
+   |                                                    ^^
+   |
+note: lifetime declared here
+  --> $DIR/impl-fn-hrtb-bounds.rs:14:20
+   |
+LL | fn c() -> impl for<'a> Fn(&'a u8) -> (impl Debug + '_) {
+   |                    ^^
+
+error: aborting due to 4 previous errors
+
+For more information about this error, try `rustc --explain E0106`.
diff --git a/src/test/ui/impl-trait/impl-fn-parsing-ambiguities.rs b/src/test/ui/impl-trait/impl-fn-parsing-ambiguities.rs
new file mode 100644
index 000000000000..61303a5b2cb4
--- /dev/null
+++ b/src/test/ui/impl-trait/impl-fn-parsing-ambiguities.rs
@@ -0,0 +1,15 @@
+#![feature(impl_trait_in_fn_trait_return)]
+use std::fmt::Debug;
+
+fn a() -> impl Fn(&u8) -> impl Debug + '_ {
+    //~^ ERROR ambiguous `+` in a type
+    //~| ERROR higher kinded lifetime bounds on nested opaque types are not supported yet
+    |x| x
+}
+
+fn b() -> impl Fn() -> impl Debug + Send {
+    //~^ ERROR ambiguous `+` in a type
+    || ()
+}
+
+fn main() {}
diff --git a/src/test/ui/impl-trait/impl-fn-parsing-ambiguities.stderr b/src/test/ui/impl-trait/impl-fn-parsing-ambiguities.stderr
new file mode 100644
index 000000000000..cf6e5ef7bace
--- /dev/null
+++ b/src/test/ui/impl-trait/impl-fn-parsing-ambiguities.stderr
@@ -0,0 +1,26 @@
+error: ambiguous `+` in a type
+  --> $DIR/impl-fn-parsing-ambiguities.rs:4:27
+   |
+LL | fn a() -> impl Fn(&u8) -> impl Debug + '_ {
+   |                           ^^^^^^^^^^^^^^^ help: use parentheses to disambiguate: `(impl Debug + '_)`
+
+error: ambiguous `+` in a type
+  --> $DIR/impl-fn-parsing-ambiguities.rs:10:24
+   |
+LL | fn b() -> impl Fn() -> impl Debug + Send {
+   |                        ^^^^^^^^^^^^^^^^^ help: use parentheses to disambiguate: `(impl Debug + Send)`
+
+error: higher kinded lifetime bounds on nested opaque types are not supported yet
+  --> $DIR/impl-fn-parsing-ambiguities.rs:4:40
+   |
+LL | fn a() -> impl Fn(&u8) -> impl Debug + '_ {
+   |                                        ^^
+   |
+note: lifetime declared here
+  --> $DIR/impl-fn-parsing-ambiguities.rs:4:19
+   |
+LL | fn a() -> impl Fn(&u8) -> impl Debug + '_ {
+   |                   ^
+
+error: aborting due to 3 previous errors
+
diff --git a/src/test/ui/impl-trait/impl-fn-predefined-lifetimes.rs b/src/test/ui/impl-trait/impl-fn-predefined-lifetimes.rs
new file mode 100644
index 000000000000..157786623754
--- /dev/null
+++ b/src/test/ui/impl-trait/impl-fn-predefined-lifetimes.rs
@@ -0,0 +1,15 @@
+#![feature(impl_trait_in_fn_trait_return)]
+use std::fmt::Debug;
+
+fn a<'a>() -> impl Fn(&'a u8) -> (impl Debug + '_) {
+    //~^ ERROR cannot resolve opaque type
+
+    |x| x
+    //~^ ERROR concrete type differs from previous defining opaque type use
+}
+
+fn _b<'a>() -> impl Fn(&'a u8) -> (impl Debug + 'a) {
+    a()
+}
+
+fn main() {}
diff --git a/src/test/ui/impl-trait/impl-fn-predefined-lifetimes.stderr b/src/test/ui/impl-trait/impl-fn-predefined-lifetimes.stderr
new file mode 100644
index 000000000000..7747319c1539
--- /dev/null
+++ b/src/test/ui/impl-trait/impl-fn-predefined-lifetimes.stderr
@@ -0,0 +1,24 @@
+error: concrete type differs from previous defining opaque type use
+  --> $DIR/impl-fn-predefined-lifetimes.rs:7:9
+   |
+LL |     |x| x
+   |         ^ expected `impl Debug + '_`, got `&u8`
+   |
+note: previous use here
+  --> $DIR/impl-fn-predefined-lifetimes.rs:7:5
+   |
+LL |     |x| x
+   |     ^^^^^
+
+error[E0720]: cannot resolve opaque type
+  --> $DIR/impl-fn-predefined-lifetimes.rs:4:35
+   |
+LL | fn a<'a>() -> impl Fn(&'a u8) -> (impl Debug + '_) {
+   |                                   ^^^^^^^^^^^^^^^ recursive opaque type
+...
+LL |     |x| x
+   |     ----- returning here with type `[closure@$DIR/impl-fn-predefined-lifetimes.rs:7:5: 7:8]`
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0720`.
diff --git a/src/test/ui/impl-trait/impl_fn_associativity.rs b/src/test/ui/impl-trait/impl_fn_associativity.rs
new file mode 100644
index 000000000000..71a8f9c77960
--- /dev/null
+++ b/src/test/ui/impl-trait/impl_fn_associativity.rs
@@ -0,0 +1,26 @@
+// run-pass
+#![feature(impl_trait_in_fn_trait_return)]
+use std::fmt::Debug;
+
+fn f_debug() -> impl Fn() -> impl Debug {
+    || ()
+}
+
+fn ff_debug() -> impl Fn() -> impl Fn() -> impl Debug {
+    || f_debug()
+}
+
+fn multi() -> impl Fn() -> (impl Debug + Send) {
+    || ()
+}
+
+fn main() {
+    // Check that `ff_debug` is `() -> (() -> Debug)` and not `(() -> ()) -> Debug`
+    let debug = ff_debug()()();
+    assert_eq!(format!("{:?}", debug), "()");
+
+    let x = multi()();
+    assert_eq!(format!("{:?}", x), "()");
+    fn assert_send(_: &impl Send) {}
+    assert_send(&x);
+}
diff --git a/src/test/ui/impl-trait/in-trait/early.rs b/src/test/ui/impl-trait/in-trait/early.rs
new file mode 100644
index 000000000000..9c1c2b503390
--- /dev/null
+++ b/src/test/ui/impl-trait/in-trait/early.rs
@@ -0,0 +1,23 @@
+// check-pass
+// edition:2021
+
+#![feature(async_fn_in_trait, return_position_impl_trait_in_trait)]
+#![allow(incomplete_features)]
+
+pub trait Foo {
+    async fn bar<'a: 'a>(&'a mut self);
+}
+
+impl Foo for () {
+    async fn bar<'a: 'a>(&'a mut self) {}
+}
+
+pub trait Foo2 {
+    fn bar<'a: 'a>(&'a mut self) -> impl Sized + 'a;
+}
+
+impl Foo2 for () {
+    fn bar<'a: 'a>(&'a mut self) -> impl Sized + 'a {}
+}
+
+fn main() {}
diff --git a/src/test/ui/impl-trait/in-trait/generics-mismatch.rs b/src/test/ui/impl-trait/in-trait/generics-mismatch.rs
new file mode 100644
index 000000000000..cc0fc720ebbf
--- /dev/null
+++ b/src/test/ui/impl-trait/in-trait/generics-mismatch.rs
@@ -0,0 +1,17 @@
+#![feature(return_position_impl_trait_in_trait)]
+#![allow(incomplete_features)]
+
+struct U;
+
+trait Foo {
+    fn bar(&self) -> impl Sized;
+}
+
+impl Foo for U {
+    fn bar<T>(&self) {}
+    //~^ ERROR method `bar` has 1 type parameter but its trait declaration has 0 type parameters
+}
+
+fn main() {
+    U.bar();
+}
diff --git a/src/test/ui/impl-trait/in-trait/generics-mismatch.stderr b/src/test/ui/impl-trait/in-trait/generics-mismatch.stderr
new file mode 100644
index 000000000000..cd42683e0224
--- /dev/null
+++ b/src/test/ui/impl-trait/in-trait/generics-mismatch.stderr
@@ -0,0 +1,12 @@
+error[E0049]: method `bar` has 1 type parameter but its trait declaration has 0 type parameters
+  --> $DIR/generics-mismatch.rs:11:12
+   |
+LL |     fn bar(&self) -> impl Sized;
+   |           - expected 0 type parameters
+...
+LL |     fn bar<T>(&self) {}
+   |            ^ found 1 type parameter
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0049`.
diff --git a/src/test/ui/impl-trait/in-trait/method-signature-matches.rs b/src/test/ui/impl-trait/in-trait/method-signature-matches.rs
new file mode 100644
index 000000000000..c848ee3f643d
--- /dev/null
+++ b/src/test/ui/impl-trait/in-trait/method-signature-matches.rs
@@ -0,0 +1,51 @@
+// edition: 2021
+
+#![feature(return_position_impl_trait_in_trait, async_fn_in_trait)]
+#![allow(incomplete_features)]
+
+trait Uwu {
+    fn owo(x: ()) -> impl Sized;
+}
+
+impl Uwu for () {
+    fn owo(_: u8) {}
+    //~^ ERROR method `owo` has an incompatible type for trait
+}
+
+trait AsyncUwu {
+    async fn owo(x: ()) {}
+}
+
+impl AsyncUwu for () {
+    async fn owo(_: u8) {}
+    //~^ ERROR method `owo` has an incompatible type for trait
+}
+
+trait TooMuch {
+    fn calm_down_please() -> impl Sized;
+}
+
+impl TooMuch for () {
+    fn calm_down_please(_: (), _: (), _: ()) {}
+    //~^ ERROR method `calm_down_please` has 3 parameters but the declaration in trait `TooMuch::calm_down_please` has 0
+}
+
+trait TooLittle {
+    fn come_on_a_little_more_effort(_: (), _: (), _: ()) -> impl Sized;
+}
+
+impl TooLittle for () {
+    fn come_on_a_little_more_effort() {}
+    //~^ ERROR method `come_on_a_little_more_effort` has 0 parameters but the declaration in trait `TooLittle::come_on_a_little_more_effort` has 3
+}
+
+trait Lifetimes {
+    fn early<'early, T>(x: &'early T) -> impl Sized;
+}
+
+impl Lifetimes for () {
+    fn early<'late, T>(_: &'late ()) {}
+    //~^ ERROR method `early` has an incompatible type for trait
+}
+
+fn main() {}
diff --git a/src/test/ui/impl-trait/in-trait/method-signature-matches.stderr b/src/test/ui/impl-trait/in-trait/method-signature-matches.stderr
new file mode 100644
index 000000000000..2b32c52c829e
--- /dev/null
+++ b/src/test/ui/impl-trait/in-trait/method-signature-matches.stderr
@@ -0,0 +1,84 @@
+error[E0053]: method `owo` has an incompatible type for trait
+  --> $DIR/method-signature-matches.rs:11:15
+   |
+LL |     fn owo(_: u8) {}
+   |               ^^
+   |               |
+   |               expected `()`, found `u8`
+   |               help: change the parameter type to match the trait: `()`
+   |
+note: type in trait
+  --> $DIR/method-signature-matches.rs:7:15
+   |
+LL |     fn owo(x: ()) -> impl Sized;
+   |               ^^
+   = note: expected fn pointer `fn(())`
+              found fn pointer `fn(u8)`
+
+error[E0053]: method `owo` has an incompatible type for trait
+  --> $DIR/method-signature-matches.rs:20:21
+   |
+LL |     async fn owo(_: u8) {}
+   |                     ^^
+   |                     |
+   |                     expected `()`, found `u8`
+   |                     help: change the parameter type to match the trait: `()`
+   |
+note: while checking the return type of the `async fn`
+  --> $DIR/method-signature-matches.rs:20:25
+   |
+LL |     async fn owo(_: u8) {}
+   |                         ^ checked the `Output` of this `async fn`, expected opaque type
+note: while checking the return type of the `async fn`
+  --> $DIR/method-signature-matches.rs:20:25
+   |
+LL |     async fn owo(_: u8) {}
+   |                         ^ checked the `Output` of this `async fn`, found opaque type
+note: type in trait
+  --> $DIR/method-signature-matches.rs:16:21
+   |
+LL |     async fn owo(x: ()) {}
+   |                     ^^
+   = note: expected fn pointer `fn(()) -> _`
+              found fn pointer `fn(u8) -> _`
+
+error[E0050]: method `calm_down_please` has 3 parameters but the declaration in trait `TooMuch::calm_down_please` has 0
+  --> $DIR/method-signature-matches.rs:29:28
+   |
+LL |     fn calm_down_please() -> impl Sized;
+   |     ------------------------------------ trait requires 0 parameters
+...
+LL |     fn calm_down_please(_: (), _: (), _: ()) {}
+   |                            ^^^^^^^^^^^^^^^^ expected 0 parameters, found 3
+
+error[E0050]: method `come_on_a_little_more_effort` has 0 parameters but the declaration in trait `TooLittle::come_on_a_little_more_effort` has 3
+  --> $DIR/method-signature-matches.rs:38:5
+   |
+LL |     fn come_on_a_little_more_effort(_: (), _: (), _: ()) -> impl Sized;
+   |                                        ---------------- trait requires 3 parameters
+...
+LL |     fn come_on_a_little_more_effort() {}
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected 3 parameters, found 0
+
+error[E0053]: method `early` has an incompatible type for trait
+  --> $DIR/method-signature-matches.rs:47:27
+   |
+LL |     fn early<'late, T>(_: &'late ()) {}
+   |                     -     ^^^^^^^^^
+   |                     |     |
+   |                     |     expected type parameter `T`, found `()`
+   |                     |     help: change the parameter type to match the trait: `&'early T`
+   |                     this type parameter
+   |
+note: type in trait
+  --> $DIR/method-signature-matches.rs:43:28
+   |
+LL |     fn early<'early, T>(x: &'early T) -> impl Sized;
+   |                            ^^^^^^^^^
+   = note: expected fn pointer `fn(&'early T)`
+              found fn pointer `fn(&())`
+
+error: aborting due to 5 previous errors
+
+Some errors have detailed explanations: E0050, E0053.
+For more information about an error, try `rustc --explain E0050`.
diff --git a/src/test/ui/impl-trait/in-trait/signature-mismatch.rs b/src/test/ui/impl-trait/in-trait/signature-mismatch.rs
new file mode 100644
index 000000000000..90682631aa03
--- /dev/null
+++ b/src/test/ui/impl-trait/in-trait/signature-mismatch.rs
@@ -0,0 +1,21 @@
+// edition:2021
+
+#![feature(return_position_impl_trait_in_trait)]
+#![allow(incomplete_features)]
+
+use std::future::Future;
+
+pub trait AsyncTrait {
+    fn async_fn(&self, buff: &[u8]) -> impl Future<Output = Vec<u8>>;
+}
+
+pub struct Struct;
+
+impl AsyncTrait for Struct {
+    fn async_fn<'a>(&self, buff: &'a [u8]) -> impl Future<Output = Vec<u8>> + 'a {
+        //~^ ERROR `impl` item signature doesn't match `trait` item signature
+        async move { buff.to_vec() }
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/impl-trait/in-trait/signature-mismatch.stderr b/src/test/ui/impl-trait/in-trait/signature-mismatch.stderr
new file mode 100644
index 000000000000..6663d7faa1e5
--- /dev/null
+++ b/src/test/ui/impl-trait/in-trait/signature-mismatch.stderr
@@ -0,0 +1,16 @@
+error: `impl` item signature doesn't match `trait` item signature
+  --> $DIR/signature-mismatch.rs:15:5
+   |
+LL |     fn async_fn(&self, buff: &[u8]) -> impl Future<Output = Vec<u8>>;
+   |     ----------------------------------------------------------------- expected `fn(&'1 Struct, &'2 [u8]) -> impl Future<Output = Vec<u8>> + 'static`
+...
+LL |     fn async_fn<'a>(&self, buff: &'a [u8]) -> impl Future<Output = Vec<u8>> + 'a {
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ found `fn(&'1 Struct, &'2 [u8]) -> impl Future<Output = Vec<u8>> + '2`
+   |
+   = note: expected `fn(&'1 Struct, &'2 [u8]) -> impl Future<Output = Vec<u8>> + 'static`
+              found `fn(&'1 Struct, &'2 [u8]) -> impl Future<Output = Vec<u8>> + '2`
+   = help: the lifetime requirements from the `impl` do not correspond to the requirements in the `trait`
+   = help: verify the lifetime relationships in the `trait` and `impl` between the `self` argument, the other inputs and its output
+
+error: aborting due to previous error
+
diff --git a/src/test/ui/impl-trait/in-trait/specialization-broken.rs b/src/test/ui/impl-trait/in-trait/specialization-broken.rs
new file mode 100644
index 000000000000..9d27d3710a60
--- /dev/null
+++ b/src/test/ui/impl-trait/in-trait/specialization-broken.rs
@@ -0,0 +1,26 @@
+// FIXME(compiler-errors): I'm not exactly sure if this is expected to pass or not.
+// But we fixed an ICE anyways.
+
+#![feature(specialization)]
+#![feature(return_position_impl_trait_in_trait)]
+#![allow(incomplete_features)]
+
+trait Foo {
+    fn bar(&self) -> impl Sized;
+}
+
+default impl<U> Foo for U
+where
+    U: Copy,
+{
+    fn bar(&self) -> U {
+        //~^ ERROR method `bar` has an incompatible type for trait
+        *self
+    }
+}
+
+impl Foo for i32 {}
+
+fn main() {
+    1i32.bar();
+}
diff --git a/src/test/ui/impl-trait/in-trait/specialization-broken.stderr b/src/test/ui/impl-trait/in-trait/specialization-broken.stderr
new file mode 100644
index 000000000000..a30e6346b292
--- /dev/null
+++ b/src/test/ui/impl-trait/in-trait/specialization-broken.stderr
@@ -0,0 +1,23 @@
+error[E0053]: method `bar` has an incompatible type for trait
+  --> $DIR/specialization-broken.rs:16:22
+   |
+LL | default impl<U> Foo for U
+   |              - this type parameter
+...
+LL |     fn bar(&self) -> U {
+   |                      ^
+   |                      |
+   |                      expected associated type, found type parameter `U`
+   |                      help: change the output type to match the trait: `impl Sized`
+   |
+note: type in trait
+  --> $DIR/specialization-broken.rs:9:22
+   |
+LL |     fn bar(&self) -> impl Sized;
+   |                      ^^^^^^^^^^
+   = note: expected fn pointer `fn(&U) -> impl Sized`
+              found fn pointer `fn(&U) -> U`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0053`.
diff --git a/src/test/ui/impl-trait/in-trait/specialization-substs-remap.rs b/src/test/ui/impl-trait/in-trait/specialization-substs-remap.rs
new file mode 100644
index 000000000000..c9ee877db8ec
--- /dev/null
+++ b/src/test/ui/impl-trait/in-trait/specialization-substs-remap.rs
@@ -0,0 +1,24 @@
+// check-pass
+
+#![feature(specialization)]
+#![feature(return_position_impl_trait_in_trait)]
+#![allow(incomplete_features)]
+
+trait Foo {
+    fn bar(&self) -> impl Sized;
+}
+
+impl<U> Foo for U
+where
+    U: Copy,
+{
+    fn bar(&self) -> U {
+        *self
+    }
+}
+
+impl Foo for i32 {}
+
+fn main() {
+    let _: i32 = 1i32.bar();
+}
diff --git a/src/test/ui/impl-trait/issue-103599.rs b/src/test/ui/impl-trait/issue-103599.rs
new file mode 100644
index 000000000000..043ae67f2e15
--- /dev/null
+++ b/src/test/ui/impl-trait/issue-103599.rs
@@ -0,0 +1,10 @@
+// check-pass
+
+trait T {}
+
+fn wrap(x: impl T) -> impl T {
+    //~^ WARN function cannot return without recursing
+    wrap(wrap(x))
+}
+
+fn main() {}
diff --git a/src/test/ui/impl-trait/issue-103599.stderr b/src/test/ui/impl-trait/issue-103599.stderr
new file mode 100644
index 000000000000..82038c1dceb3
--- /dev/null
+++ b/src/test/ui/impl-trait/issue-103599.stderr
@@ -0,0 +1,14 @@
+warning: function cannot return without recursing
+  --> $DIR/issue-103599.rs:5:1
+   |
+LL | fn wrap(x: impl T) -> impl T {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ cannot return without recursing
+LL |
+LL |     wrap(wrap(x))
+   |          ------- recursive call site
+   |
+   = help: a `loop` may express intention better if this is on purpose
+   = note: `#[warn(unconditional_recursion)]` on by default
+
+warning: 1 warning emitted
+
diff --git a/src/test/ui/impl-trait/issues/issue-92305.rs b/src/test/ui/impl-trait/issues/issue-92305.rs
index 1518c116b318..4a89238d07e6 100644
--- a/src/test/ui/impl-trait/issues/issue-92305.rs
+++ b/src/test/ui/impl-trait/issues/issue-92305.rs
@@ -4,11 +4,10 @@ use std::iter;
 
 fn f<T>(data: &[T]) -> impl Iterator<Item = Vec> {
     //~^ ERROR: missing generics for struct `Vec` [E0107]
-    iter::empty() //~ ERROR: type annotations needed [E0282]
+    iter::empty()
 }
 
 fn g<T>(data: &[T], target: T) -> impl Iterator<Item = Vec<T>> {
-    //~^ ERROR: type annotations needed [E0282]
     f(data).filter(|x| x == target)
 }
 
diff --git a/src/test/ui/impl-trait/issues/issue-92305.stderr b/src/test/ui/impl-trait/issues/issue-92305.stderr
index e8575b76b093..34d5c2d61dc4 100644
--- a/src/test/ui/impl-trait/issues/issue-92305.stderr
+++ b/src/test/ui/impl-trait/issues/issue-92305.stderr
@@ -14,24 +14,6 @@ help: add missing generic argument
 LL | fn f<T>(data: &[T]) -> impl Iterator<Item = Vec<T>> {
    |                                             ~~~~~~
 
-error[E0282]: type annotations needed
-  --> $DIR/issue-92305.rs:7:5
-   |
-LL |     iter::empty()
-   |     ^^^^^^^^^^^ cannot infer type of the type parameter `T` declared on the function `empty`
-   |
-help: consider specifying the generic argument
-   |
-LL |     iter::empty::<T>()
-   |                +++++
+error: aborting due to previous error
 
-error[E0282]: type annotations needed
-  --> $DIR/issue-92305.rs:10:35
-   |
-LL | fn g<T>(data: &[T], target: T) -> impl Iterator<Item = Vec<T>> {
-   |                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ cannot infer type
-
-error: aborting due to 3 previous errors
-
-Some errors have detailed explanations: E0107, E0282.
-For more information about an error, try `rustc --explain E0107`.
+For more information about this error, try `rustc --explain E0107`.
diff --git a/src/test/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unrelated.stderr b/src/test/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unrelated.stderr
index cb1dc0b7d50a..ec49a61795a0 100644
--- a/src/test/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unrelated.stderr
+++ b/src/test/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unrelated.stderr
@@ -7,7 +7,7 @@ LL | fn upper_bounds<'a, 'b, 'c, 'd, 'e>(a: Ordinary<'a>, b: Ordinary<'b>) -> im
 LL |     if condition() { a } else { b }
    |                                 ^
    |
-help: to declare that the `impl Trait` captures `'b`, you can add an explicit `'b` lifetime bound
+help: to declare that `impl Trait<'d, 'e>` captures `'b`, you can add an explicit `'b` lifetime bound
    |
 LL | fn upper_bounds<'a, 'b, 'c, 'd, 'e>(a: Ordinary<'a>, b: Ordinary<'b>) -> impl Trait<'d, 'e> + 'b
    |                                                                                             ++++
diff --git a/src/test/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unsuited.stderr b/src/test/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unsuited.stderr
index 4388e6601a6c..c36f9bc6957c 100644
--- a/src/test/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unsuited.stderr
+++ b/src/test/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unsuited.stderr
@@ -7,7 +7,7 @@ LL | fn upper_bounds<'a, 'b>(a: Ordinary<'a>, b: Ordinary<'b>) -> impl Trait<'a,
 LL |     if condition() { a } else { b }
    |                                 ^
    |
-help: to declare that the `impl Trait` captures `'b`, you can add an explicit `'b` lifetime bound
+help: to declare that `impl Trait<'a, 'b>` captures `'b`, you can add an explicit `'b` lifetime bound
    |
 LL | fn upper_bounds<'a, 'b>(a: Ordinary<'a>, b: Ordinary<'b>) -> impl Trait<'a, 'b> + 'b
    |                                                                                 ++++
diff --git a/src/test/ui/impl-trait/must_outlive_least_region_or_bound.stderr b/src/test/ui/impl-trait/must_outlive_least_region_or_bound.stderr
index 16767abd7224..9c81791fbcba 100644
--- a/src/test/ui/impl-trait/must_outlive_least_region_or_bound.stderr
+++ b/src/test/ui/impl-trait/must_outlive_least_region_or_bound.stderr
@@ -6,7 +6,7 @@ LL | fn elided(x: &i32) -> impl Copy { x }
    |              |
    |              hidden type `&i32` captures the anonymous lifetime defined here
    |
-help: to declare that the `impl Trait` captures `'_`, you can add an explicit `'_` lifetime bound
+help: to declare that `impl Copy` captures `'_`, you can add an explicit `'_` lifetime bound
    |
 LL | fn elided(x: &i32) -> impl Copy + '_ { x }
    |                                 ++++
@@ -19,7 +19,7 @@ LL | fn explicit<'a>(x: &'a i32) -> impl Copy { x }
    |             |
    |             hidden type `&'a i32` captures the lifetime `'a` as defined here
    |
-help: to declare that the `impl Trait` captures `'a`, you can add an explicit `'a` lifetime bound
+help: to declare that `impl Copy` captures `'a`, you can add an explicit `'a` lifetime bound
    |
 LL | fn explicit<'a>(x: &'a i32) -> impl Copy + 'a { x }
    |                                          ++++
@@ -32,7 +32,7 @@ LL | fn elided2(x: &i32) -> impl Copy + 'static { x }
    |               |
    |               let's call the lifetime of this reference `'1`
    |
-help: consider changing the `impl Trait`'s explicit `'static` bound to the lifetime of argument `x`
+help: consider changing `impl Copy + 'static`'s explicit `'static` bound to the lifetime of argument `x`
    |
 LL | fn elided2(x: &i32) -> impl Copy + '_ { x }
    |                                    ~~
@@ -47,7 +47,7 @@ error: lifetime may not live long enough
 LL | fn explicit2<'a>(x: &'a i32) -> impl Copy + 'static { x }
    |              -- lifetime `'a` defined here            ^ returning this value requires that `'a` must outlive `'static`
    |
-help: consider changing the `impl Trait`'s explicit `'static` bound to the lifetime of argument `x`
+help: consider changing `impl Copy + 'static`'s explicit `'static` bound to the lifetime of argument `x`
    |
 LL | fn explicit2<'a>(x: &'a i32) -> impl Copy + 'a { x }
    |                                             ~~
@@ -76,7 +76,7 @@ help: to declare that the trait object captures data from argument `x`, you can
    |
 LL | fn elided5(x: &i32) -> (Box<dyn Debug + '_>, impl Debug) { (Box::new(x), x) }
    |                                       ++++
-help: to declare that the `impl Trait` captures data from argument `x`, you can add an explicit `'_` lifetime bound
+help: to declare that `impl Debug` captures data from argument `x`, you can add an explicit `'_` lifetime bound
    |
 LL | fn elided5(x: &i32) -> (Box<dyn Debug>, impl Debug + '_) { (Box::new(x), x) }
    |                                                    ++++
@@ -87,7 +87,7 @@ error: lifetime may not live long enough
 LL | fn with_bound<'a>(x: &'a i32) -> impl LifetimeTrait<'a> + 'static { x }
    |               -- lifetime `'a` defined here                         ^ returning this value requires that `'a` must outlive `'static`
    |
-help: consider changing the `impl Trait`'s explicit `'static` bound to the lifetime of argument `x`
+help: consider changing `impl LifetimeTrait<'a> + 'static`'s explicit `'static` bound to the lifetime of argument `x`
    |
 LL | fn with_bound<'a>(x: &'a i32) -> impl LifetimeTrait<'a> + 'a { x }
    |                                                           ~~
@@ -104,7 +104,7 @@ LL | fn move_lifetime_into_fn<'a, 'b>(x: &'a u32, y: &'b u32) -> impl Fn(&'a u32
 LL |     move |_| println!("{}", y)
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-help: to declare that the `impl Trait` captures `'b`, you can add an explicit `'b` lifetime bound
+help: to declare that `impl Fn(&'a u32)` captures `'b`, you can add an explicit `'b` lifetime bound
    |
 LL | fn move_lifetime_into_fn<'a, 'b>(x: &'a u32, y: &'b u32) -> impl Fn(&'a u32) + 'b {
    |                                                                              ++++
diff --git a/src/test/ui/impl-trait/nested-rpit-hrtb.rs b/src/test/ui/impl-trait/nested-rpit-hrtb.rs
index abf6a7e956c6..a5db10d3a220 100644
--- a/src/test/ui/impl-trait/nested-rpit-hrtb.rs
+++ b/src/test/ui/impl-trait/nested-rpit-hrtb.rs
@@ -35,26 +35,26 @@ fn one_hrtb_outlives_uses() -> impl for<'a> Bar<'a, Assoc = impl Sized + 'a> {}
 fn one_hrtb_trait_param_uses() -> impl for<'a> Bar<'a, Assoc = impl Qux<'a>> {}
 //~^ ERROR higher kinded lifetime bounds on nested opaque types are not supported yet
 
-// This should pass.
+// This should resolve.
 fn one_hrtb_mention_fn_trait_param<'b>() -> impl for<'a> Foo<'a, Assoc = impl Qux<'b>> {}
 
-// This should pass.
+// This should resolve.
 fn one_hrtb_mention_fn_outlives<'b>() -> impl for<'a> Foo<'a, Assoc = impl Sized + 'b> {}
 
-// This should pass.
+// This should resolve.
 fn one_hrtb_mention_fn_trait_param_uses<'b>() -> impl for<'a> Bar<'a, Assoc = impl Qux<'b>> {}
 
-// This should pass.
+// This should resolve.
 fn one_hrtb_mention_fn_outlives_uses<'b>() -> impl for<'a> Bar<'a, Assoc = impl Sized + 'b> {}
 
-// This should pass.
+// This should resolve.
 fn two_htrb_trait_param() -> impl for<'a> Foo<'a, Assoc = impl for<'b> Qux<'b>> {}
 
 // `'b` is not in scope for the outlives bound.
 fn two_htrb_outlives() -> impl for<'a> Foo<'a, Assoc = impl for<'b> Sized + 'b> {}
 //~^ ERROR use of undeclared lifetime name `'b` [E0261]
 
-// This should pass.
+// This should resolve.
 fn two_htrb_trait_param_uses() -> impl for<'a> Bar<'a, Assoc = impl for<'b> Qux<'b>> {}
 
 // `'b` is not in scope for the outlives bound.
diff --git a/src/test/ui/impl-trait/nested_impl_trait.rs b/src/test/ui/impl-trait/nested_impl_trait.rs
index 85c6f8c462cb..e95fab3b6505 100644
--- a/src/test/ui/impl-trait/nested_impl_trait.rs
+++ b/src/test/ui/impl-trait/nested_impl_trait.rs
@@ -1,3 +1,4 @@
+#![feature(impl_trait_in_fn_trait_return)]
 use std::fmt::Debug;
 
 fn fine(x: impl Into<u32>) -> impl Into<u32> { x }
@@ -25,8 +26,7 @@ fn allowed_in_assoc_type() -> impl Iterator<Item=impl Fn()> {
 }
 
 fn allowed_in_ret_type() -> impl Fn() -> impl Into<u32> {
-//~^ `impl Trait` only allowed in function and inherent method return types
-    || 5
+    || 5u8
 }
 
 fn main() {}
diff --git a/src/test/ui/impl-trait/nested_impl_trait.stderr b/src/test/ui/impl-trait/nested_impl_trait.stderr
index 3291cad6882e..9a8f5a340681 100644
--- a/src/test/ui/impl-trait/nested_impl_trait.stderr
+++ b/src/test/ui/impl-trait/nested_impl_trait.stderr
@@ -1,5 +1,5 @@
 error[E0666]: nested `impl Trait` is not allowed
-  --> $DIR/nested_impl_trait.rs:5:56
+  --> $DIR/nested_impl_trait.rs:6:56
    |
 LL | fn bad_in_ret_position(x: impl Into<u32>) -> impl Into<impl Debug> { x }
    |                                              ----------^^^^^^^^^^-
@@ -8,7 +8,7 @@ LL | fn bad_in_ret_position(x: impl Into<u32>) -> impl Into<impl Debug> { x }
    |                                              outer `impl Trait`
 
 error[E0666]: nested `impl Trait` is not allowed
-  --> $DIR/nested_impl_trait.rs:9:42
+  --> $DIR/nested_impl_trait.rs:10:42
    |
 LL | fn bad_in_fn_syntax(x: fn() -> impl Into<impl Debug>) {}
    |                                ----------^^^^^^^^^^-
@@ -17,7 +17,7 @@ LL | fn bad_in_fn_syntax(x: fn() -> impl Into<impl Debug>) {}
    |                                outer `impl Trait`
 
 error[E0666]: nested `impl Trait` is not allowed
-  --> $DIR/nested_impl_trait.rs:13:37
+  --> $DIR/nested_impl_trait.rs:14:37
    |
 LL | fn bad_in_arg_position(_: impl Into<impl Debug>) { }
    |                           ----------^^^^^^^^^^-
@@ -26,7 +26,7 @@ LL | fn bad_in_arg_position(_: impl Into<impl Debug>) { }
    |                           outer `impl Trait`
 
 error[E0666]: nested `impl Trait` is not allowed
-  --> $DIR/nested_impl_trait.rs:18:44
+  --> $DIR/nested_impl_trait.rs:19:44
    |
 LL |     fn bad(x: impl Into<u32>) -> impl Into<impl Debug> { x }
    |                                  ----------^^^^^^^^^^-
@@ -35,19 +35,13 @@ LL |     fn bad(x: impl Into<u32>) -> impl Into<impl Debug> { x }
    |                                  outer `impl Trait`
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `fn` pointer return
-  --> $DIR/nested_impl_trait.rs:9:32
+  --> $DIR/nested_impl_trait.rs:10:32
    |
 LL | fn bad_in_fn_syntax(x: fn() -> impl Into<impl Debug>) {}
    |                                ^^^^^^^^^^^^^^^^^^^^^
 
-error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait return
-  --> $DIR/nested_impl_trait.rs:27:42
-   |
-LL | fn allowed_in_ret_type() -> impl Fn() -> impl Into<u32> {
-   |                                          ^^^^^^^^^^^^^^
-
 error[E0277]: the trait bound `impl Debug: From<impl Into<u32>>` is not satisfied
-  --> $DIR/nested_impl_trait.rs:5:46
+  --> $DIR/nested_impl_trait.rs:6:46
    |
 LL | fn bad_in_ret_position(x: impl Into<u32>) -> impl Into<impl Debug> { x }
    |                                              ^^^^^^^^^^^^^^^^^^^^^ the trait `From<impl Into<u32>>` is not implemented for `impl Debug`
@@ -56,7 +50,7 @@ LL | fn bad_in_ret_position(x: impl Into<u32>) -> impl Into<impl Debug> { x }
    = note: required for `impl Into<u32>` to implement `Into<impl Debug>`
 
 error[E0277]: the trait bound `impl Debug: From<impl Into<u32>>` is not satisfied
-  --> $DIR/nested_impl_trait.rs:18:34
+  --> $DIR/nested_impl_trait.rs:19:34
    |
 LL |     fn bad(x: impl Into<u32>) -> impl Into<impl Debug> { x }
    |                                  ^^^^^^^^^^^^^^^^^^^^^ the trait `From<impl Into<u32>>` is not implemented for `impl Debug`
@@ -64,7 +58,7 @@ LL |     fn bad(x: impl Into<u32>) -> impl Into<impl Debug> { x }
    = help: the trait `Into<U>` is implemented for `T`
    = note: required for `impl Into<u32>` to implement `Into<impl Debug>`
 
-error: aborting due to 8 previous errors
+error: aborting due to 7 previous errors
 
 Some errors have detailed explanations: E0277, E0562, E0666.
 For more information about an error, try `rustc --explain E0277`.
diff --git a/src/test/ui/impl-trait/region-escape-via-bound.stderr b/src/test/ui/impl-trait/region-escape-via-bound.stderr
index fdb2fe022b4d..44a790cb1a43 100644
--- a/src/test/ui/impl-trait/region-escape-via-bound.stderr
+++ b/src/test/ui/impl-trait/region-escape-via-bound.stderr
@@ -7,7 +7,7 @@ LL | fn foo<'x, 'y>(x: Cell<&'x u32>) -> impl Trait<'y>
 LL |     x
    |     ^
    |
-help: to declare that the `impl Trait` captures `'x`, you can add an explicit `'x` lifetime bound
+help: to declare that `impl Trait<'y>` captures `'x`, you can add an explicit `'x` lifetime bound
    |
 LL | fn foo<'x, 'y>(x: Cell<&'x u32>) -> impl Trait<'y> + 'x
    |                                                    ++++
diff --git a/src/test/ui/impl-trait/static-return-lifetime-infered.stderr b/src/test/ui/impl-trait/static-return-lifetime-infered.stderr
index b86815231550..b365bd884548 100644
--- a/src/test/ui/impl-trait/static-return-lifetime-infered.stderr
+++ b/src/test/ui/impl-trait/static-return-lifetime-infered.stderr
@@ -6,7 +6,7 @@ LL |     fn iter_values_anon(&self) -> impl Iterator<Item=u32> {
 LL |         self.x.iter().map(|a| a.0)
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-help: to declare that the `impl Trait` captures `'_`, you can add an explicit `'_` lifetime bound
+help: to declare that `impl Iterator<Item = u32>` captures `'_`, you can add an explicit `'_` lifetime bound
    |
 LL |     fn iter_values_anon(&self) -> impl Iterator<Item=u32> + '_ {
    |                                                           ++++
@@ -19,7 +19,7 @@ LL |     fn iter_values_anon(&self) -> impl Iterator<Item=u32> {
 LL |         self.x.iter().map(|a| a.0)
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-help: to declare that the `impl Trait` captures `'_`, you can add an explicit `'_` lifetime bound
+help: to declare that `impl Iterator<Item = u32>` captures `'_`, you can add an explicit `'_` lifetime bound
    |
 LL |     fn iter_values_anon(&self) -> impl Iterator<Item=u32> + '_ {
    |                                                           ++++
@@ -32,7 +32,7 @@ LL |     fn iter_values<'a>(&'a self) -> impl Iterator<Item=u32> {
 LL |         self.x.iter().map(|a| a.0)
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-help: to declare that the `impl Trait` captures `'a`, you can add an explicit `'a` lifetime bound
+help: to declare that `impl Iterator<Item = u32>` captures `'a`, you can add an explicit `'a` lifetime bound
    |
 LL |     fn iter_values<'a>(&'a self) -> impl Iterator<Item=u32> + 'a {
    |                                                             ++++
@@ -45,7 +45,7 @@ LL |     fn iter_values<'a>(&'a self) -> impl Iterator<Item=u32> {
 LL |         self.x.iter().map(|a| a.0)
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-help: to declare that the `impl Trait` captures `'a`, you can add an explicit `'a` lifetime bound
+help: to declare that `impl Iterator<Item = u32>` captures `'a`, you can add an explicit `'a` lifetime bound
    |
 LL |     fn iter_values<'a>(&'a self) -> impl Iterator<Item=u32> + 'a {
    |                                                             ++++
diff --git a/src/test/ui/impl-trait/where-allowed.rs b/src/test/ui/impl-trait/where-allowed.rs
index c1dd46c7ff7f..ff63b04c2680 100644
--- a/src/test/ui/impl-trait/where-allowed.rs
+++ b/src/test/ui/impl-trait/where-allowed.rs
@@ -1,5 +1,6 @@
 //! A simple test for testing many permutations of allowedness of
 //! impl Trait
+#![feature(impl_trait_in_fn_trait_return)]
 use std::fmt::Debug;
 
 // Allowed
@@ -39,9 +40,8 @@ fn in_dyn_Fn_return_in_parameters(_: &dyn Fn() -> impl Debug) { panic!() }
 fn in_dyn_Fn_parameter_in_return() -> &'static dyn Fn(impl Debug) { panic!() }
 //~^ ERROR `impl Trait` only allowed in function and inherent method return types
 
-// Disallowed
+// Allowed
 fn in_dyn_Fn_return_in_return() -> &'static dyn Fn() -> impl Debug { panic!() }
-//~^ ERROR `impl Trait` only allowed in function and inherent method return types
 
 // Disallowed
 fn in_impl_Fn_parameter_in_parameters(_: &impl Fn(impl Debug)) { panic!() }
@@ -57,9 +57,8 @@ fn in_impl_Fn_parameter_in_return() -> &'static impl Fn(impl Debug) { panic!() }
 //~^ ERROR `impl Trait` only allowed in function and inherent method return types
 //~| ERROR nested `impl Trait` is not allowed
 
-// Disallowed
+// Allowed
 fn in_impl_Fn_return_in_return() -> &'static impl Fn() -> impl Debug { panic!() }
-//~^ ERROR `impl Trait` only allowed in function and inherent method return types
 
 // Disallowed
 fn in_Fn_parameter_in_generics<F: Fn(impl Debug)> (_: F) { panic!() }
diff --git a/src/test/ui/impl-trait/where-allowed.stderr b/src/test/ui/impl-trait/where-allowed.stderr
index 2e7c7ca40ddb..3ad0a9f9d5c8 100644
--- a/src/test/ui/impl-trait/where-allowed.stderr
+++ b/src/test/ui/impl-trait/where-allowed.stderr
@@ -17,7 +17,7 @@ LL | fn in_impl_Fn_parameter_in_return() -> &'static impl Fn(impl Debug) { panic
    |                                                 outer `impl Trait`
 
 error[E0658]: `impl Trait` in type aliases is unstable
-  --> $DIR/where-allowed.rs:119:16
+  --> $DIR/where-allowed.rs:118:16
    |
 LL |     type Out = impl Debug;
    |                ^^^^^^^^^^
@@ -26,7 +26,7 @@ LL |     type Out = impl Debug;
    = help: add `#![feature(type_alias_impl_trait)]` to the crate attributes to enable
 
 error[E0658]: `impl Trait` in type aliases is unstable
-  --> $DIR/where-allowed.rs:154:23
+  --> $DIR/where-allowed.rs:153:23
    |
 LL | type InTypeAlias<R> = impl Debug;
    |                       ^^^^^^^^^^
@@ -35,7 +35,7 @@ LL | type InTypeAlias<R> = impl Debug;
    = help: add `#![feature(type_alias_impl_trait)]` to the crate attributes to enable
 
 error[E0658]: `impl Trait` in type aliases is unstable
-  --> $DIR/where-allowed.rs:157:39
+  --> $DIR/where-allowed.rs:156:39
    |
 LL | type InReturnInTypeAlias<R> = fn() -> impl Debug;
    |                                       ^^^^^^^^^^
@@ -44,53 +44,47 @@ LL | type InReturnInTypeAlias<R> = fn() -> impl Debug;
    = help: add `#![feature(type_alias_impl_trait)]` to the crate attributes to enable
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `fn` pointer param
-  --> $DIR/where-allowed.rs:15:40
+  --> $DIR/where-allowed.rs:16:40
    |
 LL | fn in_fn_parameter_in_parameters(_: fn(impl Debug)) { panic!() }
    |                                        ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `fn` pointer return
-  --> $DIR/where-allowed.rs:19:42
+  --> $DIR/where-allowed.rs:20:42
    |
 LL | fn in_fn_return_in_parameters(_: fn() -> impl Debug) { panic!() }
    |                                          ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `fn` pointer param
-  --> $DIR/where-allowed.rs:23:38
+  --> $DIR/where-allowed.rs:24:38
    |
 LL | fn in_fn_parameter_in_return() -> fn(impl Debug) { panic!() }
    |                                      ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `fn` pointer return
-  --> $DIR/where-allowed.rs:27:40
+  --> $DIR/where-allowed.rs:28:40
    |
 LL | fn in_fn_return_in_return() -> fn() -> impl Debug { panic!() }
    |                                        ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait param
-  --> $DIR/where-allowed.rs:31:49
+  --> $DIR/where-allowed.rs:32:49
    |
 LL | fn in_dyn_Fn_parameter_in_parameters(_: &dyn Fn(impl Debug)) { panic!() }
    |                                                 ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait return
-  --> $DIR/where-allowed.rs:35:51
+  --> $DIR/where-allowed.rs:36:51
    |
 LL | fn in_dyn_Fn_return_in_parameters(_: &dyn Fn() -> impl Debug) { panic!() }
    |                                                   ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait param
-  --> $DIR/where-allowed.rs:39:55
+  --> $DIR/where-allowed.rs:40:55
    |
 LL | fn in_dyn_Fn_parameter_in_return() -> &'static dyn Fn(impl Debug) { panic!() }
    |                                                       ^^^^^^^^^^
 
-error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait return
-  --> $DIR/where-allowed.rs:43:57
-   |
-LL | fn in_dyn_Fn_return_in_return() -> &'static dyn Fn() -> impl Debug { panic!() }
-   |                                                         ^^^^^^^^^^
-
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait param
   --> $DIR/where-allowed.rs:47:51
    |
@@ -109,56 +103,50 @@ error[E0562]: `impl Trait` only allowed in function and inherent method return t
 LL | fn in_impl_Fn_parameter_in_return() -> &'static impl Fn(impl Debug) { panic!() }
    |                                                         ^^^^^^^^^^
 
-error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait return
-  --> $DIR/where-allowed.rs:61:59
-   |
-LL | fn in_impl_Fn_return_in_return() -> &'static impl Fn() -> impl Debug { panic!() }
-   |                                                           ^^^^^^^^^^
-
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait param
-  --> $DIR/where-allowed.rs:65:38
+  --> $DIR/where-allowed.rs:64:38
    |
 LL | fn in_Fn_parameter_in_generics<F: Fn(impl Debug)> (_: F) { panic!() }
    |                                      ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait return
-  --> $DIR/where-allowed.rs:69:40
+  --> $DIR/where-allowed.rs:68:40
    |
 LL | fn in_Fn_return_in_generics<F: Fn() -> impl Debug> (_: F) { panic!() }
    |                                        ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
-  --> $DIR/where-allowed.rs:82:32
+  --> $DIR/where-allowed.rs:81:32
    |
 LL | struct InBraceStructField { x: impl Debug }
    |                                ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in path
-  --> $DIR/where-allowed.rs:86:41
+  --> $DIR/where-allowed.rs:85:41
    |
 LL | struct InAdtInBraceStructField { x: Vec<impl Debug> }
    |                                         ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
-  --> $DIR/where-allowed.rs:90:27
+  --> $DIR/where-allowed.rs:89:27
    |
 LL | struct InTupleStructField(impl Debug);
    |                           ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
-  --> $DIR/where-allowed.rs:95:25
+  --> $DIR/where-allowed.rs:94:25
    |
 LL |     InBraceVariant { x: impl Debug },
    |                         ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
-  --> $DIR/where-allowed.rs:97:20
+  --> $DIR/where-allowed.rs:96:20
    |
 LL |     InTupleVariant(impl Debug),
    |                    ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in trait method return
-  --> $DIR/where-allowed.rs:108:23
+  --> $DIR/where-allowed.rs:107:23
    |
 LL |     fn in_return() -> impl Debug;
    |                       ^^^^^^^^^^
@@ -167,7 +155,7 @@ LL |     fn in_return() -> impl Debug;
    = help: add `#![feature(return_position_impl_trait_in_trait)]` to the crate attributes to enable
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `impl` method return
-  --> $DIR/where-allowed.rs:125:34
+  --> $DIR/where-allowed.rs:124:34
    |
 LL |     fn in_trait_impl_return() -> impl Debug { () }
    |                                  ^^^^^^^^^^
@@ -176,127 +164,127 @@ LL |     fn in_trait_impl_return() -> impl Debug { () }
    = help: add `#![feature(return_position_impl_trait_in_trait)]` to the crate attributes to enable
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `extern fn` param
-  --> $DIR/where-allowed.rs:138:33
+  --> $DIR/where-allowed.rs:137:33
    |
 LL |     fn in_foreign_parameters(_: impl Debug);
    |                                 ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `extern fn` return
-  --> $DIR/where-allowed.rs:141:31
+  --> $DIR/where-allowed.rs:140:31
    |
 LL |     fn in_foreign_return() -> impl Debug;
    |                               ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `fn` pointer return
-  --> $DIR/where-allowed.rs:157:39
+  --> $DIR/where-allowed.rs:156:39
    |
 LL | type InReturnInTypeAlias<R> = fn() -> impl Debug;
    |                                       ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in trait
-  --> $DIR/where-allowed.rs:162:16
+  --> $DIR/where-allowed.rs:161:16
    |
 LL | impl PartialEq<impl Debug> for () {
    |                ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
-  --> $DIR/where-allowed.rs:167:24
+  --> $DIR/where-allowed.rs:166:24
    |
 LL | impl PartialEq<()> for impl Debug {
    |                        ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
-  --> $DIR/where-allowed.rs:172:6
+  --> $DIR/where-allowed.rs:171:6
    |
 LL | impl impl Debug {
    |      ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
-  --> $DIR/where-allowed.rs:178:24
+  --> $DIR/where-allowed.rs:177:24
    |
 LL | impl InInherentImplAdt<impl Debug> {
    |                        ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
-  --> $DIR/where-allowed.rs:184:11
+  --> $DIR/where-allowed.rs:183:11
    |
 LL |     where impl Debug: Debug
    |           ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
-  --> $DIR/where-allowed.rs:191:15
+  --> $DIR/where-allowed.rs:190:15
    |
 LL |     where Vec<impl Debug>: Debug
    |               ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in bound
-  --> $DIR/where-allowed.rs:198:24
+  --> $DIR/where-allowed.rs:197:24
    |
 LL |     where T: PartialEq<impl Debug>
    |                        ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait param
-  --> $DIR/where-allowed.rs:205:17
+  --> $DIR/where-allowed.rs:204:17
    |
 LL |     where T: Fn(impl Debug)
    |                 ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `Fn` trait return
-  --> $DIR/where-allowed.rs:212:22
+  --> $DIR/where-allowed.rs:211:22
    |
 LL |     where T: Fn() -> impl Debug
    |                      ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
-  --> $DIR/where-allowed.rs:218:40
+  --> $DIR/where-allowed.rs:217:40
    |
 LL | struct InStructGenericParamDefault<T = impl Debug>(T);
    |                                        ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
-  --> $DIR/where-allowed.rs:222:36
+  --> $DIR/where-allowed.rs:221:36
    |
 LL | enum InEnumGenericParamDefault<T = impl Debug> { Variant(T) }
    |                                    ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
-  --> $DIR/where-allowed.rs:226:38
+  --> $DIR/where-allowed.rs:225:38
    |
 LL | trait InTraitGenericParamDefault<T = impl Debug> {}
    |                                      ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
-  --> $DIR/where-allowed.rs:230:41
+  --> $DIR/where-allowed.rs:229:41
    |
 LL | type InTypeAliasGenericParamDefault<T = impl Debug> = T;
    |                                         ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
-  --> $DIR/where-allowed.rs:234:11
+  --> $DIR/where-allowed.rs:233:11
    |
 LL | impl <T = impl Debug> T {}
    |           ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in type
-  --> $DIR/where-allowed.rs:241:40
+  --> $DIR/where-allowed.rs:240:40
    |
 LL | fn in_method_generic_param_default<T = impl Debug>(_: T) {}
    |                                        ^^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in variable binding
-  --> $DIR/where-allowed.rs:247:29
+  --> $DIR/where-allowed.rs:246:29
    |
 LL |     let _in_local_variable: impl Fn() = || {};
    |                             ^^^^^^^^^
 
 error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in closure return
-  --> $DIR/where-allowed.rs:249:46
+  --> $DIR/where-allowed.rs:248:46
    |
 LL |     let _in_return_in_local_variable = || -> impl Fn() { || {} };
    |                                              ^^^^^^^^^
 
 error: defaults for type parameters are only allowed in `struct`, `enum`, `type`, or `trait` definitions
-  --> $DIR/where-allowed.rs:234:7
+  --> $DIR/where-allowed.rs:233:7
    |
 LL | impl <T = impl Debug> T {}
    |       ^^^^^^^^^^^^^^
@@ -306,7 +294,7 @@ LL | impl <T = impl Debug> T {}
    = note: `#[deny(invalid_type_param_default)]` on by default
 
 error: defaults for type parameters are only allowed in `struct`, `enum`, `type`, or `trait` definitions
-  --> $DIR/where-allowed.rs:241:36
+  --> $DIR/where-allowed.rs:240:36
    |
 LL | fn in_method_generic_param_default<T = impl Debug>(_: T) {}
    |                                    ^^^^^^^^^^^^^^
@@ -315,14 +303,14 @@ LL | fn in_method_generic_param_default<T = impl Debug>(_: T) {}
    = note: for more information, see issue #36887 <https://github.com/rust-lang/rust/issues/36887>
 
 error[E0118]: no nominal type found for inherent implementation
-  --> $DIR/where-allowed.rs:234:23
+  --> $DIR/where-allowed.rs:233:23
    |
 LL | impl <T = impl Debug> T {}
    |                       ^ impl requires a nominal type
    |
    = note: either implement a trait on it or create a newtype to wrap it instead
 
-error: aborting due to 49 previous errors
+error: aborting due to 47 previous errors
 
 Some errors have detailed explanations: E0118, E0562, E0658, E0666.
 For more information about an error, try `rustc --explain E0118`.
diff --git a/src/test/ui/implied-bounds/hrlt-implied-trait-bounds-guard.rs b/src/test/ui/implied-bounds/hrlt-implied-trait-bounds-guard.rs
index d9de73a38eff..79844dcbdacf 100644
--- a/src/test/ui/implied-bounds/hrlt-implied-trait-bounds-guard.rs
+++ b/src/test/ui/implied-bounds/hrlt-implied-trait-bounds-guard.rs
@@ -31,6 +31,16 @@ fn badboi<'in_, 'out, T>(x: Foo<'in_, 'out, T>, sadness: &'in_ T) -> &'out T {
     sadness.cast()
 }
 
+fn badboi2<'in_, 'out, T>(x: Foo<'in_, 'out, T>, sadness: &'in_ T) {
+    //~^ ERROR lifetime mismatch
+    let _: &'out T = sadness.cast();
+}
+
+fn badboi3<'in_, 'out, T>(a: Foo<'in_, 'out, (&'in_ T, &'out T)>, sadness: &'in_ T) {
+    //~^ ERROR lifetime mismatch
+    let _: &'out T = sadness.cast();
+}
+
 fn bad<'short, T>(value: &'short T) -> &'static T {
     let x: for<'in_, 'out> fn(Foo<'in_, 'out, T>, &'in_ T) -> &'out T = badboi;
     let x: for<'out> fn(Foo<'short, 'out, T>, &'short T) -> &'out T = x;
diff --git a/src/test/ui/implied-bounds/hrlt-implied-trait-bounds-guard.stderr b/src/test/ui/implied-bounds/hrlt-implied-trait-bounds-guard.stderr
index b020ea64bf46..0c00bbc380e8 100644
--- a/src/test/ui/implied-bounds/hrlt-implied-trait-bounds-guard.stderr
+++ b/src/test/ui/implied-bounds/hrlt-implied-trait-bounds-guard.stderr
@@ -7,6 +7,24 @@ LL | fn badboi<'in_, 'out, T>(x: Foo<'in_, 'out, T>, sadness: &'in_ T) -> &'out
    |                             this parameter and the return type are declared with different lifetimes...
    |                             ...but data from `x` is returned here
 
-error: aborting due to previous error
+error[E0623]: lifetime mismatch
+  --> $DIR/hrlt-implied-trait-bounds-guard.rs:34:30
+   |
+LL | fn badboi2<'in_, 'out, T>(x: Foo<'in_, 'out, T>, sadness: &'in_ T) {
+   |                              ^^^^^^^^^^^^^^^^^^
+   |                              |
+   |                              this type is declared with multiple lifetimes...
+   |                              ...but data with one lifetime flows into the other here
+
+error[E0623]: lifetime mismatch
+  --> $DIR/hrlt-implied-trait-bounds-guard.rs:39:30
+   |
+LL | fn badboi3<'in_, 'out, T>(a: Foo<'in_, 'out, (&'in_ T, &'out T)>, sadness: &'in_ T) {
+   |                              ^^^^^^^^^^^^^^^^^-------^^-------^^
+   |                              |                |
+   |                              |                these two types are declared with different lifetimes...
+   |                              ...but data from `a` flows into `a` here
+
+error: aborting due to 3 previous errors
 
 For more information about this error, try `rustc --explain E0623`.
diff --git a/src/test/ui/inference/cannot-infer-async.rs b/src/test/ui/inference/cannot-infer-async.rs
index e7fabd0ffbc8..b5152d04f695 100644
--- a/src/test/ui/inference/cannot-infer-async.rs
+++ b/src/test/ui/inference/cannot-infer-async.rs
@@ -10,6 +10,7 @@ fn main() {
     let fut = async {
         make_unit()?;
 
-        Ok(()) //~ ERROR type annotations needed
+        Ok(())
+        //~^ ERROR type annotations needed
     };
 }
diff --git a/src/test/ui/inference/cannot-infer-closure.rs b/src/test/ui/inference/cannot-infer-closure.rs
index 1c350b18f5a6..bd5d10b41734 100644
--- a/src/test/ui/inference/cannot-infer-closure.rs
+++ b/src/test/ui/inference/cannot-infer-closure.rs
@@ -1,6 +1,7 @@
 fn main() {
     let x = |a: (), b: ()| {
         Err(a)?;
-        Ok(b) //~ ERROR type annotations needed
+        Ok(b)
+        //~^ ERROR type annotations needed
     };
 }
diff --git a/src/test/ui/inference/issue-103587.rs b/src/test/ui/inference/issue-103587.rs
new file mode 100644
index 000000000000..11536f9f4cc4
--- /dev/null
+++ b/src/test/ui/inference/issue-103587.rs
@@ -0,0 +1,12 @@
+fn main() {
+    let x = Some(123);
+
+    if let Some(_) == x {}
+    //~^ ERROR expected `=`, found `==`
+
+    if Some(_) = x {}
+    //~^ ERROR mismatched types
+
+    if None = x { }
+    //~^ ERROR mismatched types
+}
diff --git a/src/test/ui/inference/issue-103587.stderr b/src/test/ui/inference/issue-103587.stderr
new file mode 100644
index 000000000000..b373fbfbb948
--- /dev/null
+++ b/src/test/ui/inference/issue-103587.stderr
@@ -0,0 +1,40 @@
+error: expected `=`, found `==`
+  --> $DIR/issue-103587.rs:4:20
+   |
+LL |     if let Some(_) == x {}
+   |                    ^^
+   |
+help: consider using `=` here
+   |
+LL |     if let Some(_) = x {}
+   |                    ~
+
+error[E0308]: mismatched types
+  --> $DIR/issue-103587.rs:7:8
+   |
+LL |     if Some(_) = x {}
+   |        ^^^^^^^^^^^ expected `bool`, found `()`
+   |
+help: consider adding `let`
+   |
+LL |     if let Some(_) = x {}
+   |        +++
+
+error[E0308]: mismatched types
+  --> $DIR/issue-103587.rs:10:8
+   |
+LL |     if None = x { }
+   |        ^^^^^^^^ expected `bool`, found `()`
+   |
+help: you might have meant to use pattern matching
+   |
+LL |     if let None = x { }
+   |        +++
+help: you might have meant to compare for equality
+   |
+LL |     if None == x { }
+   |              +
+
+error: aborting due to 3 previous errors
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/ui/inference/issue-71732.rs b/src/test/ui/inference/issue-71732.rs
index 30063a0957c7..8a9d2b235f0e 100644
--- a/src/test/ui/inference/issue-71732.rs
+++ b/src/test/ui/inference/issue-71732.rs
@@ -15,7 +15,8 @@ use std::collections::hash_map::HashMap;
 
 fn foo(parameters: &HashMap<String, String>) -> bool {
     parameters
-        .get(&"key".into()) //~ ERROR: type annotations needed
+        .get(&"key".into())
+        //~^ ERROR type annotations needed
         .and_then(|found: &String| Some(false))
         .unwrap_or(false)
 }
diff --git a/src/test/ui/inference/issue-72616.rs b/src/test/ui/inference/issue-72616.rs
index 5e5a3babfe02..69ade1a7515c 100644
--- a/src/test/ui/inference/issue-72616.rs
+++ b/src/test/ui/inference/issue-72616.rs
@@ -1,3 +1,5 @@
+// ignore-wasm32 FIXME: ignoring wasm as it suggests slightly different impls
+
 // Regression test for #72616, it used to emit incorrect diagnostics, like:
 // error[E0283]: type annotations needed for `String`
 //  --> src/main.rs:8:30
@@ -18,7 +20,8 @@ pub fn main() {
     }
     {
         if String::from("a") == "a".try_into().unwrap() {}
-        //~^ ERROR: type annotations needed
+        //~^ ERROR type annotations needed
+        //~| ERROR type annotations needed
     }
     {
         let _: String = match "_".try_into() {
diff --git a/src/test/ui/inference/issue-72616.stderr b/src/test/ui/inference/issue-72616.stderr
index a71ce9a8ef27..6ee0626cab85 100644
--- a/src/test/ui/inference/issue-72616.stderr
+++ b/src/test/ui/inference/issue-72616.stderr
@@ -1,5 +1,5 @@
 error[E0283]: type annotations needed
-  --> $DIR/issue-72616.rs:20:37
+  --> $DIR/issue-72616.rs:22:37
    |
 LL |         if String::from("a") == "a".try_into().unwrap() {}
    |                              --     ^^^^^^^^
@@ -16,6 +16,22 @@ help: try using a fully qualified path to specify the expected types
 LL |         if String::from("a") == <&str as TryInto<T>>::try_into("a").unwrap() {}
    |                                 +++++++++++++++++++++++++++++++   ~
 
-error: aborting due to previous error
+error[E0283]: type annotations needed
+  --> $DIR/issue-72616.rs:22:37
+   |
+LL |         if String::from("a") == "a".try_into().unwrap() {}
+   |                                     ^^^^^^^^
+   |
+   = note: multiple `impl`s satisfying `_: TryFrom<&str>` found in the following crates: `core`, `std`:
+           - impl<> TryFrom<&str> for std::sys_common::net::LookupHost;
+           - impl<T, U> TryFrom<U> for T
+             where U: Into<T>;
+   = note: required for `&str` to implement `TryInto<_>`
+help: try using a fully qualified path to specify the expected types
+   |
+LL |         if String::from("a") == <&str as TryInto<T>>::try_into("a").unwrap() {}
+   |                                 +++++++++++++++++++++++++++++++   ~
+
+error: aborting due to 2 previous errors
 
 For more information about this error, try `rustc --explain E0283`.
diff --git a/src/test/ui/inference/question-mark-type-infer.rs b/src/test/ui/inference/question-mark-type-infer.rs
index 64333a29313b..10560f85ed48 100644
--- a/src/test/ui/inference/question-mark-type-infer.rs
+++ b/src/test/ui/inference/question-mark-type-infer.rs
@@ -7,7 +7,8 @@ fn f(x: &i32) -> Result<i32, ()> {
 
 fn g() -> Result<Vec<i32>, ()> {
     let l = [1, 2, 3, 4];
-    l.iter().map(f).collect()? //~ ERROR type annotations needed
+    l.iter().map(f).collect()?
+    //~^ ERROR type annotations needed
 }
 
 fn main() {
diff --git a/src/test/ui/intrinsics/panic-uninitialized-zeroed.rs b/src/test/ui/intrinsics/panic-uninitialized-zeroed.rs
index ae44ffd29bd5..ec3860a322fc 100644
--- a/src/test/ui/intrinsics/panic-uninitialized-zeroed.rs
+++ b/src/test/ui/intrinsics/panic-uninitialized-zeroed.rs
@@ -7,7 +7,7 @@
 
 // This test checks panic emitted from `mem::{uninitialized,zeroed}`.
 
-#![feature(never_type, arbitrary_enum_discriminant)]
+#![feature(never_type)]
 #![allow(deprecated, invalid_value)]
 
 use std::{
diff --git a/src/test/ui/issues/issue-12127.rs b/src/test/ui/issues/issue-12127.rs
index 8b30ddc2de67..199d542e816f 100644
--- a/src/test/ui/issues/issue-12127.rs
+++ b/src/test/ui/issues/issue-12127.rs
@@ -1,6 +1,6 @@
-#![feature(unboxed_closures)]
+#![feature(unboxed_closures, tuple_trait)]
 
-fn to_fn_once<A,F:FnOnce<A>>(f: F) -> F { f }
+fn to_fn_once<A:std::marker::Tuple,F:FnOnce<A>>(f: F) -> F { f }
 fn do_it(x: &isize) { }
 
 fn main() {
diff --git a/src/test/ui/issues/issue-1460.stderr b/src/test/ui/issues/issue-1460.stderr
index f0ff2cafd446..eb7661fad56d 100644
--- a/src/test/ui/issues/issue-1460.stderr
+++ b/src/test/ui/issues/issue-1460.stderr
@@ -2,7 +2,7 @@ warning: unused closure that must be used
   --> $DIR/issue-1460.rs:6:5
    |
 LL |     {|i: u32| if 1 == i { }};
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: closures are lazy and do nothing unless called
    = note: `#[warn(unused_must_use)]` on by default
diff --git a/src/test/ui/issues/issue-16256.stderr b/src/test/ui/issues/issue-16256.stderr
index ca8e9a1bed33..d920530b57c6 100644
--- a/src/test/ui/issues/issue-16256.stderr
+++ b/src/test/ui/issues/issue-16256.stderr
@@ -2,7 +2,7 @@ warning: unused closure that must be used
   --> $DIR/issue-16256.rs:6:5
    |
 LL |     |c: u8| buf.push(c);
-   |     ^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^
    |
    = note: closures are lazy and do nothing unless called
    = note: `#[warn(unused_must_use)]` on by default
diff --git a/src/test/ui/issues/issue-23024.stderr b/src/test/ui/issues/issue-23024.stderr
index 73f93c51d34e..dc8b34a70c32 100644
--- a/src/test/ui/issues/issue-23024.stderr
+++ b/src/test/ui/issues/issue-23024.stderr
@@ -16,7 +16,7 @@ LL |     println!("{:?}",(vfnfer[0] as dyn Fn)(3));
 note: trait defined here, with 1 generic parameter: `Args`
   --> $SRC_DIR/core/src/ops/function.rs:LL:COL
    |
-LL | pub trait Fn<Args>: FnMut<Args> {
+LL | pub trait Fn<Args: Tuple>: FnMut<Args> {
    |           ^^ ----
 help: add missing generic argument
    |
diff --git a/src/test/ui/issues/issue-28105.stderr b/src/test/ui/issues/issue-28105.stderr
index 42ed838d7c03..f450256f3ecf 100644
--- a/src/test/ui/issues/issue-28105.stderr
+++ b/src/test/ui/issues/issue-28105.stderr
@@ -4,11 +4,11 @@ error[E0268]: `continue` outside of a loop
 LL |     continue
    |     ^^^^^^^^ cannot `continue` outside of a loop
 
-error[E0268]: `break` outside of a loop
+error[E0268]: `break` outside of a loop or labeled block
   --> $DIR/issue-28105.rs:6:5
    |
 LL |     break
-   |     ^^^^^ cannot `break` outside of a loop
+   |     ^^^^^ cannot `break` outside of a loop or labeled block
 
 error: aborting due to 2 previous errors
 
diff --git a/src/test/ui/issues/issue-28568.stderr b/src/test/ui/issues/issue-28568.stderr
index be3f7c627800..960259080f73 100644
--- a/src/test/ui/issues/issue-28568.stderr
+++ b/src/test/ui/issues/issue-28568.stderr
@@ -1,4 +1,4 @@
-error[E0119]: conflicting implementations of trait `std::ops::Drop` for type `MyStruct`
+error[E0119]: conflicting implementations of trait `Drop` for type `MyStruct`
   --> $DIR/issue-28568.rs:7:1
    |
 LL | impl Drop for MyStruct {
diff --git a/src/test/ui/issues/issue-32655.stderr b/src/test/ui/issues/issue-32655.stderr
index 2d9ce430a462..5a758c7002b9 100644
--- a/src/test/ui/issues/issue-32655.stderr
+++ b/src/test/ui/issues/issue-32655.stderr
@@ -2,18 +2,28 @@ error: cannot find attribute `derive_Clone` in this scope
   --> $DIR/issue-32655.rs:3:11
    |
 LL |         #[derive_Clone]
-   |           ^^^^^^^^^^^^
+   |           ^^^^^^^^^^^^ help: an attribute macro with a similar name exists: `derive_const`
 ...
 LL | foo!();
    | ------ in this macro invocation
    |
+  ::: $SRC_DIR/core/src/macros/mod.rs:LL:COL
+   |
+LL |     pub macro derive_const($item:item) {
+   |     ---------------------- similarly named attribute macro `derive_const` defined here
+   |
    = note: this error originates in the macro `foo` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: cannot find attribute `derive_Clone` in this scope
   --> $DIR/issue-32655.rs:15:7
    |
 LL |     #[derive_Clone]
-   |       ^^^^^^^^^^^^
+   |       ^^^^^^^^^^^^ help: an attribute macro with a similar name exists: `derive_const`
+   |
+  ::: $SRC_DIR/core/src/macros/mod.rs:LL:COL
+   |
+LL |     pub macro derive_const($item:item) {
+   |     ---------------------- similarly named attribute macro `derive_const` defined here
 
 error: aborting due to 2 previous errors
 
diff --git a/src/test/ui/issues/issue-3707.stderr b/src/test/ui/issues/issue-3707.stderr
index 6ca2deee377a..07c8101cbc68 100644
--- a/src/test/ui/issues/issue-3707.stderr
+++ b/src/test/ui/issues/issue-3707.stderr
@@ -2,10 +2,10 @@ error[E0599]: no method named `boom` found for reference `&Obj` in the current s
   --> $DIR/issue-3707.rs:10:14
    |
 LL |         self.boom();
-   |         -----^^^^
+   |         -----^^^^--
    |         |    |
    |         |    this is an associated function, not a method
-   |         help: use associated function syntax instead: `Obj::boom`
+   |         help: use associated function syntax instead: `Obj::boom()`
    |
    = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
 note: the candidate is defined in an impl for the type `Obj`
diff --git a/src/test/ui/issues/issue-43162.stderr b/src/test/ui/issues/issue-43162.stderr
index a443db40732a..40d9200058ed 100644
--- a/src/test/ui/issues/issue-43162.stderr
+++ b/src/test/ui/issues/issue-43162.stderr
@@ -1,14 +1,14 @@
-error[E0268]: `break` outside of a loop
+error[E0268]: `break` outside of a loop or labeled block
   --> $DIR/issue-43162.rs:3:5
    |
 LL |     break true;
-   |     ^^^^^^^^^^ cannot `break` outside of a loop
+   |     ^^^^^^^^^^ cannot `break` outside of a loop or labeled block
 
-error[E0268]: `break` outside of a loop
+error[E0268]: `break` outside of a loop or labeled block
   --> $DIR/issue-43162.rs:7:5
    |
 LL |     break {};
-   |     ^^^^^^^^ cannot `break` outside of a loop
+   |     ^^^^^^^^ cannot `break` outside of a loop or labeled block
 
 error[E0308]: mismatched types
   --> $DIR/issue-43162.rs:1:13
diff --git a/src/test/ui/issues/issue-43355.stderr b/src/test/ui/issues/issue-43355.stderr
index 531130fecab1..57adc8ad5efc 100644
--- a/src/test/ui/issues/issue-43355.stderr
+++ b/src/test/ui/issues/issue-43355.stderr
@@ -1,4 +1,4 @@
-error[E0119]: conflicting implementations of trait `Trait1<std::boxed::Box<_>>` for type `A`
+error[E0119]: conflicting implementations of trait `Trait1<Box<_>>` for type `A`
   --> $DIR/issue-43355.rs:13:1
    |
 LL | impl<X, T> Trait1<X> for T where T: Trait2<X> {
diff --git a/src/test/ui/issues/issue-47184.stderr b/src/test/ui/issues/issue-47184.stderr
index f97713b4ac43..c2c7df7a333a 100644
--- a/src/test/ui/issues/issue-47184.stderr
+++ b/src/test/ui/issues/issue-47184.stderr
@@ -4,7 +4,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     let _vec: Vec<&'static String> = vec![&String::new()];
    |               --------------------         ^^^^^^^^^^^^^ - temporary value is freed at the end of this statement
    |               |                            |
-   |               |                            creates a temporary which is freed while still in use
+   |               |                            creates a temporary value which is freed while still in use
    |               type annotation requires that borrow lasts for `'static`
 
 error: aborting due to previous error
diff --git a/src/test/ui/issues/issue-47511.stderr b/src/test/ui/issues/issue-47511.stderr
deleted file mode 100644
index 9998ee0e8d0c..000000000000
--- a/src/test/ui/issues/issue-47511.stderr
+++ /dev/null
@@ -1,18 +0,0 @@
-error[E0581]: return type references an anonymous lifetime, which is not constrained by the fn input types
-  --> $DIR/issue-47511.rs:8:15
-   |
-LL | fn f(_: X) -> X {
-   |               ^
-   |
-   = note: lifetimes appearing in an associated or opaque type are not considered constrained
-   = note: consider introducing a named lifetime parameter
-
-error[E0581]: return type references lifetime `'a`, which is not constrained by the fn input types
-  --> $DIR/issue-47511.rs:12:23
-   |
-LL | fn g<'a>(_: X<'a>) -> X<'a> {
-   |                       ^^^^^
-
-error: aborting due to 2 previous errors
-
-For more information about this error, try `rustc --explain E0581`.
diff --git a/src/test/ui/issues/issue-48728.rs b/src/test/ui/issues/issue-48728.rs
index 8405a30478bd..cbdc10bd2e1e 100644
--- a/src/test/ui/issues/issue-48728.rs
+++ b/src/test/ui/issues/issue-48728.rs
@@ -1,7 +1,7 @@
 // Regression test for #48728, an ICE that occurred computing
 // coherence "help" information.
 
-#[derive(Clone)] //~ ERROR conflicting implementations of trait `std::clone::Clone`
+#[derive(Clone)] //~ ERROR conflicting implementations of trait `Clone`
 struct Node<T: ?Sized>(Box<T>);
 
 impl<T: Clone + ?Sized> Clone for Node<[T]> {
diff --git a/src/test/ui/issues/issue-48728.stderr b/src/test/ui/issues/issue-48728.stderr
index 628f026b6804..0bb46724f616 100644
--- a/src/test/ui/issues/issue-48728.stderr
+++ b/src/test/ui/issues/issue-48728.stderr
@@ -1,4 +1,4 @@
-error[E0119]: conflicting implementations of trait `std::clone::Clone` for type `Node<[_]>`
+error[E0119]: conflicting implementations of trait `Clone` for type `Node<[_]>`
   --> $DIR/issue-48728.rs:4:10
    |
 LL | #[derive(Clone)]
diff --git a/src/test/ui/issues/issue-50576.stderr b/src/test/ui/issues/issue-50576.stderr
index 9fea1411080f..4ec22fde9106 100644
--- a/src/test/ui/issues/issue-50576.stderr
+++ b/src/test/ui/issues/issue-50576.stderr
@@ -4,17 +4,17 @@ error[E0426]: use of undeclared label `'L`
 LL |     |bool: [u8; break 'L]| 0;
    |                       ^^ undeclared label `'L`
 
-error[E0268]: `break` outside of a loop
+error[E0268]: `break` outside of a loop or labeled block
   --> $DIR/issue-50576.rs:2:17
    |
 LL |     |bool: [u8; break 'L]| 0;
-   |                 ^^^^^^^^ cannot `break` outside of a loop
+   |                 ^^^^^^^^ cannot `break` outside of a loop or labeled block
 
-error[E0268]: `break` outside of a loop
+error[E0268]: `break` outside of a loop or labeled block
   --> $DIR/issue-50576.rs:5:16
    |
 LL |     Vec::<[u8; break]>::new();
-   |                ^^^^^ cannot `break` outside of a loop
+   |                ^^^^^ cannot `break` outside of a loop or labeled block
 
 error: aborting due to 3 previous errors
 
diff --git a/src/test/ui/issues/issue-50581.stderr b/src/test/ui/issues/issue-50581.stderr
index 35d6fc49cedc..07b6df072cb4 100644
--- a/src/test/ui/issues/issue-50581.stderr
+++ b/src/test/ui/issues/issue-50581.stderr
@@ -1,8 +1,8 @@
-error[E0268]: `break` outside of a loop
+error[E0268]: `break` outside of a loop or labeled block
   --> $DIR/issue-50581.rs:2:14
    |
 LL |     |_: [u8; break]| ();
-   |              ^^^^^ cannot `break` outside of a loop
+   |              ^^^^^ cannot `break` outside of a loop or labeled block
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/issues/issue-52049.stderr b/src/test/ui/issues/issue-52049.stderr
index 55929d85da45..b25dbd1cb8b1 100644
--- a/src/test/ui/issues/issue-52049.stderr
+++ b/src/test/ui/issues/issue-52049.stderr
@@ -4,7 +4,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     foo(&unpromotable(5u32));
    |     -----^^^^^^^^^^^^^^^^^^-
    |     |    |
-   |     |    creates a temporary which is freed while still in use
+   |     |    creates a temporary value which is freed while still in use
    |     argument requires that borrow lasts for `'static`
 LL | }
    | - temporary value is freed at the end of this statement
diff --git a/src/test/ui/issues/issue-69396-const-no-type-in-macro.stderr b/src/test/ui/issues/issue-69396-const-no-type-in-macro.stderr
index f581429a2815..89aeafebac49 100644
--- a/src/test/ui/issues/issue-69396-const-no-type-in-macro.stderr
+++ b/src/test/ui/issues/issue-69396-const-no-type-in-macro.stderr
@@ -2,10 +2,7 @@ error[E0428]: the name `A` is defined multiple times
   --> $DIR/issue-69396-const-no-type-in-macro.rs:4:13
    |
 LL |               const A = "A".$fn();
-   |               ^^^^^^^^^^^^^^^^^^^^
-   |               |
-   |               `A` redefined here
-   |               previous definition of the value `A` here
+   |               ^^^^^^^^^^^^^^^^^^^^ `A` redefined here
 ...
 LL | / suite! {
 LL | |     len;
diff --git a/src/test/ui/issues/issue-71584.rs b/src/test/ui/issues/issue-71584.rs
index c96cd598f0ce..7bf3ed60ec10 100644
--- a/src/test/ui/issues/issue-71584.rs
+++ b/src/test/ui/issues/issue-71584.rs
@@ -1,5 +1,6 @@
 fn main() {
     let n: u32 = 1;
     let mut d: u64 = 2;
-    d = d % n.into(); //~ ERROR type annotations needed
+    d = d % n.into();
+    //~^ ERROR type annotations needed
 }
diff --git a/src/test/ui/issues/issue-7607-1.stderr b/src/test/ui/issues/issue-7607-1.stderr
index ecff8b42b0ea..f1ab0ad26d70 100644
--- a/src/test/ui/issues/issue-7607-1.stderr
+++ b/src/test/ui/issues/issue-7607-1.stderr
@@ -6,8 +6,8 @@ LL | impl Fo {
    |
   ::: $SRC_DIR/core/src/ops/function.rs:LL:COL
    |
-LL | pub trait Fn<Args>: FnMut<Args> {
-   | ------------------------------- similarly named trait `Fn` defined here
+LL | pub trait Fn<Args: Tuple>: FnMut<Args> {
+   | -------------------------------------- similarly named trait `Fn` defined here
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/issues/issue-7970a.stderr b/src/test/ui/issues/issue-7970a.stderr
index ea400d7e1917..b04a0eef3713 100644
--- a/src/test/ui/issues/issue-7970a.stderr
+++ b/src/test/ui/issues/issue-7970a.stderr
@@ -6,6 +6,12 @@ LL | macro_rules! one_arg_macro {
 ...
 LL |     one_arg_macro!();
    |     ^^^^^^^^^^^^^^^^ missing tokens in macro arguments
+   |
+note: while trying to match meta-variable `$fmt:expr`
+  --> $DIR/issue-7970a.rs:2:6
+   |
+LL |     ($fmt:expr) => (print!(concat!($fmt, "\n")));
+   |      ^^^^^^^^^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/issues/issue-83048.rs b/src/test/ui/issues/issue-83048.rs
index 520ae974398b..8e4fb6eae9df 100644
--- a/src/test/ui/issues/issue-83048.rs
+++ b/src/test/ui/issues/issue-83048.rs
@@ -1,5 +1,5 @@
 // compile-flags: -Z unpretty=thir-tree
 
 pub fn main() {
-    break; //~ ERROR: `break` outside of a loop [E0268]
+    break; //~ ERROR: `break` outside of a loop or labeled block [E0268]
 }
diff --git a/src/test/ui/issues/issue-83048.stderr b/src/test/ui/issues/issue-83048.stderr
index 62d67d75844a..dade9e469503 100644
--- a/src/test/ui/issues/issue-83048.stderr
+++ b/src/test/ui/issues/issue-83048.stderr
@@ -1,8 +1,8 @@
-error[E0268]: `break` outside of a loop
+error[E0268]: `break` outside of a loop or labeled block
   --> $DIR/issue-83048.rs:4:5
    |
 LL |     break;
-   |     ^^^^^ cannot `break` outside of a loop
+   |     ^^^^^ cannot `break` outside of a loop or labeled block
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/iterators/collect-into-array.rs b/src/test/ui/iterators/collect-into-array.rs
index 7d35da825328..4c424999b754 100644
--- a/src/test/ui/iterators/collect-into-array.rs
+++ b/src/test/ui/iterators/collect-into-array.rs
@@ -1,5 +1,4 @@
 fn main() {
-    //~^ NOTE required by a bound in this
     let whatever: [u32; 10] = (0..10).collect();
     //~^ ERROR an array of type `[u32; 10]` cannot be built directly from an iterator
     //~| NOTE try collecting into a `Vec<{integer}>`, then using `.try_into()`
diff --git a/src/test/ui/iterators/collect-into-array.stderr b/src/test/ui/iterators/collect-into-array.stderr
index 7fe9707e6d23..a23a36a88abb 100644
--- a/src/test/ui/iterators/collect-into-array.stderr
+++ b/src/test/ui/iterators/collect-into-array.stderr
@@ -1,5 +1,5 @@
 error[E0277]: an array of type `[u32; 10]` cannot be built directly from an iterator
-  --> $DIR/collect-into-array.rs:3:31
+  --> $DIR/collect-into-array.rs:2:31
    |
 LL |     let whatever: [u32; 10] = (0..10).collect();
    |                               ^^^^^^^ ------- required by a bound introduced by this call
diff --git a/src/test/ui/iterators/collect-into-slice.rs b/src/test/ui/iterators/collect-into-slice.rs
index 5eade075613f..09832c260d04 100644
--- a/src/test/ui/iterators/collect-into-slice.rs
+++ b/src/test/ui/iterators/collect-into-slice.rs
@@ -1,6 +1,4 @@
 fn process_slice(data: &[i32]) {
-    //~^ NOTE required by a bound in this
-    //~| NOTE required by a bound in this
     todo!()
 }
 
diff --git a/src/test/ui/iterators/collect-into-slice.stderr b/src/test/ui/iterators/collect-into-slice.stderr
index bce40118bdfa..bc152467ce3a 100644
--- a/src/test/ui/iterators/collect-into-slice.stderr
+++ b/src/test/ui/iterators/collect-into-slice.stderr
@@ -1,5 +1,5 @@
 error[E0277]: the size for values of type `[i32]` cannot be known at compilation time
-  --> $DIR/collect-into-slice.rs:8:9
+  --> $DIR/collect-into-slice.rs:6:9
    |
 LL |     let some_generated_vec = (0..10).collect();
    |         ^^^^^^^^^^^^^^^^^^ doesn't have a size known at compile-time
@@ -9,7 +9,7 @@ LL |     let some_generated_vec = (0..10).collect();
    = help: unsized locals are gated as an unstable feature
 
 error[E0277]: the size for values of type `[i32]` cannot be known at compilation time
-  --> $DIR/collect-into-slice.rs:8:38
+  --> $DIR/collect-into-slice.rs:6:38
    |
 LL |     let some_generated_vec = (0..10).collect();
    |                                      ^^^^^^^ doesn't have a size known at compile-time
@@ -22,7 +22,7 @@ LL |     fn collect<B: FromIterator<Self::Item>>(self) -> B
    |                ^ required by this bound in `collect`
 
 error[E0277]: a slice of type `[i32]` cannot be built since `[i32]` has no definite size
-  --> $DIR/collect-into-slice.rs:8:30
+  --> $DIR/collect-into-slice.rs:6:30
    |
 LL |     let some_generated_vec = (0..10).collect();
    |                              ^^^^^^^ ------- required by a bound introduced by this call
diff --git a/src/test/ui/lang-items/lang-item-missing-generator.rs b/src/test/ui/lang-items/lang-item-missing-generator.rs
index 0c329542928c..9b9aff38e524 100644
--- a/src/test/ui/lang-items/lang-item-missing-generator.rs
+++ b/src/test/ui/lang-items/lang-item-missing-generator.rs
@@ -1,12 +1,14 @@
 // error-pattern: requires `generator` lang_item
-#![feature(no_core, lang_items, unboxed_closures)]
+#![feature(no_core, lang_items, unboxed_closures, tuple_trait)]
 #![no_core]
 
 #[lang = "sized"] pub trait Sized { }
 
+#[lang = "tuple_trait"] pub trait Tuple { }
+
 #[lang = "fn_once"]
 #[rustc_paren_sugar]
-pub trait FnOnce<Args> {
+pub trait FnOnce<Args: Tuple> {
     type Output;
 
     extern "rust-call" fn call_once(self, args: Args) -> Self::Output;
diff --git a/src/test/ui/lang-items/lang-item-missing-generator.stderr b/src/test/ui/lang-items/lang-item-missing-generator.stderr
index fa13bf0b1271..a24fdb5fb650 100644
--- a/src/test/ui/lang-items/lang-item-missing-generator.stderr
+++ b/src/test/ui/lang-items/lang-item-missing-generator.stderr
@@ -1,8 +1,15 @@
+error[E0635]: unknown feature `tuple_trait`
+  --> $DIR/lang-item-missing-generator.rs:2:51
+   |
+LL | #![feature(no_core, lang_items, unboxed_closures, tuple_trait)]
+   |                                                   ^^^^^^^^^^^
+
 error: requires `generator` lang_item
-  --> $DIR/lang-item-missing-generator.rs:15:17
+  --> $DIR/lang-item-missing-generator.rs:17:17
    |
 LL | pub fn abc() -> impl FnOnce(f32) {
    |                 ^^^^^^^^^^^^^^^^
 
-error: aborting due to previous error
+error: aborting due to 2 previous errors
 
+For more information about this error, try `rustc --explain E0635`.
diff --git a/src/test/ui/late-bound-lifetimes/auxiliary/upstream_alias.rs b/src/test/ui/late-bound-lifetimes/auxiliary/upstream_alias.rs
new file mode 100644
index 000000000000..5b9dc0e43087
--- /dev/null
+++ b/src/test/ui/late-bound-lifetimes/auxiliary/upstream_alias.rs
@@ -0,0 +1,5 @@
+pub trait Trait<'a> {
+    type Assoc;
+}
+
+pub type Alias<'a, T> = <T as Trait<'a>>::Assoc;
diff --git a/src/test/ui/late-bound-lifetimes/cross_crate_alias.rs b/src/test/ui/late-bound-lifetimes/cross_crate_alias.rs
new file mode 100644
index 000000000000..4154c2792432
--- /dev/null
+++ b/src/test/ui/late-bound-lifetimes/cross_crate_alias.rs
@@ -0,0 +1,10 @@
+// aux-build:upstream_alias.rs
+// check-pass
+
+extern crate upstream_alias;
+
+fn foo<'a, T: for<'b> upstream_alias::Trait<'b>>(_: upstream_alias::Alias<'a, T>) -> &'a () {
+    todo!()
+}
+
+fn main() {}
diff --git a/src/test/ui/late-bound-lifetimes/downgraded_to_early_through_alias.rs b/src/test/ui/late-bound-lifetimes/downgraded_to_early_through_alias.rs
new file mode 100644
index 000000000000..e56a34218e23
--- /dev/null
+++ b/src/test/ui/late-bound-lifetimes/downgraded_to_early_through_alias.rs
@@ -0,0 +1,24 @@
+// check-pass
+
+trait Gats<'a> {
+    type Assoc;
+    type Assoc2;
+}
+
+trait Trait: for<'a> Gats<'a> {
+    fn foo<'a>(_: &mut <Self as Gats<'a>>::Assoc) -> <Self as Gats<'a>>::Assoc2;
+}
+
+impl<'a> Gats<'a> for () {
+    type Assoc = &'a u32;
+    type Assoc2 = ();
+}
+
+type GatsAssoc<'a, T> = <T as Gats<'a>>::Assoc;
+type GatsAssoc2<'a, T> = <T as Gats<'a>>::Assoc2;
+
+impl Trait for () {
+    fn foo<'a>(_: &mut GatsAssoc<'a, Self>) -> GatsAssoc2<'a, Self> {}
+}
+
+fn main() {}
diff --git a/src/test/ui/issues/issue-47511.rs b/src/test/ui/late-bound-lifetimes/issue-47511.rs
similarity index 52%
rename from src/test/ui/issues/issue-47511.rs
rename to src/test/ui/late-bound-lifetimes/issue-47511.rs
index eb4860e75d75..789443515408 100644
--- a/src/test/ui/issues/issue-47511.rs
+++ b/src/test/ui/late-bound-lifetimes/issue-47511.rs
@@ -1,9 +1,4 @@
-// check-fail
-// known-bug: #47511
-
-// Regression test for #47511: anonymous lifetimes can appear
-// unconstrained in a return type, but only if they appear just once
-// in the input, as the input to a projection.
+// check-pass
 
 fn f(_: X) -> X {
     unimplemented!()
diff --git a/src/test/ui/late-bound-lifetimes/late_bound_through_alias.rs b/src/test/ui/late-bound-lifetimes/late_bound_through_alias.rs
new file mode 100644
index 000000000000..91839673c1f7
--- /dev/null
+++ b/src/test/ui/late-bound-lifetimes/late_bound_through_alias.rs
@@ -0,0 +1,16 @@
+// check-pass
+
+fn f(_: X) -> X {
+    unimplemented!()
+}
+
+fn g<'a>(_: X<'a>) -> X<'a> {
+    unimplemented!()
+}
+
+type X<'a> = &'a ();
+
+fn main() {
+    let _: for<'a> fn(X<'a>) -> X<'a> = g;
+    let _: for<'a> fn(X<'a>) -> X<'a> = f;
+}
diff --git a/src/test/ui/late-bound-lifetimes/mismatched_arg_count.rs b/src/test/ui/late-bound-lifetimes/mismatched_arg_count.rs
new file mode 100644
index 000000000000..0b331e2039f2
--- /dev/null
+++ b/src/test/ui/late-bound-lifetimes/mismatched_arg_count.rs
@@ -0,0 +1,12 @@
+// ensures that we don't ICE when there are too many args supplied to the alias.
+
+trait Trait<'a> {
+    type Assoc;
+}
+
+type Alias<'a, T> = <T as Trait<'a>>::Assoc;
+
+fn bar<'a, T: Trait<'a>>(_: Alias<'a, 'a, T>) {}
+//~^ error: this type alias takes 1 lifetime argument but 2 lifetime arguments were supplied
+
+fn main() {}
diff --git a/src/test/ui/late-bound-lifetimes/mismatched_arg_count.stderr b/src/test/ui/late-bound-lifetimes/mismatched_arg_count.stderr
new file mode 100644
index 000000000000..3704d9bb957e
--- /dev/null
+++ b/src/test/ui/late-bound-lifetimes/mismatched_arg_count.stderr
@@ -0,0 +1,17 @@
+error[E0107]: this type alias takes 1 lifetime argument but 2 lifetime arguments were supplied
+  --> $DIR/mismatched_arg_count.rs:9:29
+   |
+LL | fn bar<'a, T: Trait<'a>>(_: Alias<'a, 'a, T>) {}
+   |                             ^^^^^     -- help: remove this lifetime argument
+   |                             |
+   |                             expected 1 lifetime argument
+   |
+note: type alias defined here, with 1 lifetime parameter: `'a`
+  --> $DIR/mismatched_arg_count.rs:7:6
+   |
+LL | type Alias<'a, T> = <T as Trait<'a>>::Assoc;
+   |      ^^^^^ --
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0107`.
diff --git a/src/test/ui/let-else/let-else-irrefutable.rs b/src/test/ui/let-else/let-else-irrefutable.rs
index 1cb68ecb8a6b..f4b338eb0af9 100644
--- a/src/test/ui/let-else/let-else-irrefutable.rs
+++ b/src/test/ui/let-else/let-else-irrefutable.rs
@@ -1,7 +1,11 @@
 // check-pass
 
-
-
 fn main() {
     let x = 1 else { return }; //~ WARN irrefutable `let...else` pattern
+
+    // Multiline else blocks should not get printed
+    let x = 1 else { //~ WARN irrefutable `let...else` pattern
+        eprintln!("problem case encountered");
+        return
+    };
 }
diff --git a/src/test/ui/let-else/let-else-irrefutable.stderr b/src/test/ui/let-else/let-else-irrefutable.stderr
index e0581f4d9ab6..73d4e5f34831 100644
--- a/src/test/ui/let-else/let-else-irrefutable.stderr
+++ b/src/test/ui/let-else/let-else-irrefutable.stderr
@@ -1,12 +1,21 @@
 warning: irrefutable `let...else` pattern
-  --> $DIR/let-else-irrefutable.rs:6:5
+  --> $DIR/let-else-irrefutable.rs:4:5
    |
 LL |     let x = 1 else { return };
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^
    |
    = note: this pattern will always match, so the `else` clause is useless
    = help: consider removing the `else` clause
    = note: `#[warn(irrefutable_let_patterns)]` on by default
 
-warning: 1 warning emitted
+warning: irrefutable `let...else` pattern
+  --> $DIR/let-else-irrefutable.rs:7:5
+   |
+LL |     let x = 1 else {
+   |     ^^^^^^^^^
+   |
+   = note: this pattern will always match, so the `else` clause is useless
+   = help: consider removing the `else` clause
+
+warning: 2 warnings emitted
 
diff --git a/src/test/ui/lexical-scopes.stderr b/src/test/ui/lexical-scopes.stderr
index 535985452232..f0eaa1a5c64c 100644
--- a/src/test/ui/lexical-scopes.stderr
+++ b/src/test/ui/lexical-scopes.stderr
@@ -2,7 +2,7 @@ error[E0574]: expected struct, variant or union type, found type parameter `T`
   --> $DIR/lexical-scopes.rs:3:13
    |
 LL | struct T { i: i32 }
-   | ------------------- you might have meant to refer to this struct
+   |        - you might have meant to refer to this struct
 LL | fn f<T>() {
    |      - found this type parameter
 LL |     let t = T { i: 0 };
diff --git a/src/test/ui/lifetimes/borrowck-let-suggestion.stderr b/src/test/ui/lifetimes/borrowck-let-suggestion.stderr
index bbf04c98436e..987b051b1110 100644
--- a/src/test/ui/lifetimes/borrowck-let-suggestion.stderr
+++ b/src/test/ui/lifetimes/borrowck-let-suggestion.stderr
@@ -4,7 +4,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     let mut x = vec![1].iter();
    |                 ^^^^^^^       - temporary value is freed at the end of this statement
    |                 |
-   |                 creates a temporary which is freed while still in use
+   |                 creates a temporary value which is freed while still in use
 LL |
 LL |     x.use_mut();
    |     ----------- borrow later used here
diff --git a/src/test/ui/lifetimes/lifetime-elision-return-type-requires-explicit-lifetime.rs b/src/test/ui/lifetimes/lifetime-elision-return-type-requires-explicit-lifetime.rs
index 7a2eba518fef..d0a8fe795efd 100644
--- a/src/test/ui/lifetimes/lifetime-elision-return-type-requires-explicit-lifetime.rs
+++ b/src/test/ui/lifetimes/lifetime-elision-return-type-requires-explicit-lifetime.rs
@@ -42,4 +42,10 @@ fn k<'a, T: WithLifetime<'a>>(_x: T::Output) -> &isize {
     panic!()
 }
 
+fn l<'a>(_: &'a str, _: &'a str) -> &str { "" }
+//~^ ERROR missing lifetime specifier
+
+// This is ok because both `'a` are for the same parameter.
+fn m<'a>(_: &'a Foo<'a>) -> &str { "" }
+
 fn main() {}
diff --git a/src/test/ui/lifetimes/lifetime-elision-return-type-requires-explicit-lifetime.stderr b/src/test/ui/lifetimes/lifetime-elision-return-type-requires-explicit-lifetime.stderr
index d07754879559..5eee953ef189 100644
--- a/src/test/ui/lifetimes/lifetime-elision-return-type-requires-explicit-lifetime.stderr
+++ b/src/test/ui/lifetimes/lifetime-elision-return-type-requires-explicit-lifetime.stderr
@@ -70,6 +70,18 @@ help: consider using the `'a` lifetime
 LL | fn k<'a, T: WithLifetime<'a>>(_x: T::Output) -> &'a isize {
    |                                                  ++
 
-error: aborting due to 6 previous errors
+error[E0106]: missing lifetime specifier
+  --> $DIR/lifetime-elision-return-type-requires-explicit-lifetime.rs:45:37
+   |
+LL | fn l<'a>(_: &'a str, _: &'a str) -> &str { "" }
+   |             -------     -------     ^ expected named lifetime parameter
+   |
+   = help: this function's return type contains a borrowed value with an elided lifetime, but the lifetime cannot be derived from the arguments
+help: consider using the `'a` lifetime
+   |
+LL | fn l<'a>(_: &'a str, _: &'a str) -> &'a str { "" }
+   |                                      ++
+
+error: aborting due to 7 previous errors
 
 For more information about this error, try `rustc --explain E0106`.
diff --git a/src/test/ui/lint/dead-code/multiple-dead-codes-in-the-same-struct.rs b/src/test/ui/lint/dead-code/multiple-dead-codes-in-the-same-struct.rs
index e3935cf9149b..2003e1e293a5 100644
--- a/src/test/ui/lint/dead-code/multiple-dead-codes-in-the-same-struct.rs
+++ b/src/test/ui/lint/dead-code/multiple-dead-codes-in-the-same-struct.rs
@@ -7,7 +7,7 @@ struct Bar {
     b: usize, //~ ERROR field `b` is never read
     #[deny(dead_code)]
     c: usize, //~ ERROR fields `c` and `e` are never read
-    d: usize, //~ WARN fields `d`, `f` and `g` are never read
+    d: usize, //~ WARN fields `d`, `f`, and `g` are never read
     #[deny(dead_code)]
     e: usize,
     f: usize,
diff --git a/src/test/ui/lint/dead-code/multiple-dead-codes-in-the-same-struct.stderr b/src/test/ui/lint/dead-code/multiple-dead-codes-in-the-same-struct.stderr
index c0f1ed38f6de..0e5c78a71679 100644
--- a/src/test/ui/lint/dead-code/multiple-dead-codes-in-the-same-struct.stderr
+++ b/src/test/ui/lint/dead-code/multiple-dead-codes-in-the-same-struct.stderr
@@ -1,4 +1,4 @@
-warning: fields `d`, `f` and `g` are never read
+warning: fields `d`, `f`, and `g` are never read
   --> $DIR/multiple-dead-codes-in-the-same-struct.rs:10:5
    |
 LL | struct Bar {
diff --git a/src/test/ui/lint/dead-code/tuple-struct-field.rs b/src/test/ui/lint/dead-code/tuple-struct-field.rs
index b15d70636863..14fb30be949d 100644
--- a/src/test/ui/lint/dead-code/tuple-struct-field.rs
+++ b/src/test/ui/lint/dead-code/tuple-struct-field.rs
@@ -11,7 +11,7 @@ struct SingleUnused(i32, [u8; LEN], String);
 //~| HELP: consider changing the field to be of unit type
 
 struct MultipleUnused(i32, f32, String, u8);
-//~^ ERROR: fields `0`, `1`, `2` and `3` are never read
+//~^ ERROR: fields `0`, `1`, `2`, and `3` are never read
 //~| NOTE: fields in this struct
 //~| HELP: consider changing the fields to be of unit type
 
diff --git a/src/test/ui/lint/dead-code/tuple-struct-field.stderr b/src/test/ui/lint/dead-code/tuple-struct-field.stderr
index ca0989f5b987..b8ad5cbe4e97 100644
--- a/src/test/ui/lint/dead-code/tuple-struct-field.stderr
+++ b/src/test/ui/lint/dead-code/tuple-struct-field.stderr
@@ -16,7 +16,7 @@ help: consider changing the field to be of unit type to suppress this warning wh
 LL | struct SingleUnused(i32, (), String);
    |                          ~~
 
-error: fields `0`, `1`, `2` and `3` are never read
+error: fields `0`, `1`, `2`, and `3` are never read
   --> $DIR/tuple-struct-field.rs:13:23
    |
 LL | struct MultipleUnused(i32, f32, String, u8);
diff --git a/src/test/ui/lint/fn_must_use.stderr b/src/test/ui/lint/fn_must_use.stderr
index 2805720f035b..657f23c60856 100644
--- a/src/test/ui/lint/fn_must_use.stderr
+++ b/src/test/ui/lint/fn_must_use.stderr
@@ -2,7 +2,7 @@ warning: unused return value of `need_to_use_this_value` that must be used
   --> $DIR/fn_must_use.rs:55:5
    |
 LL |     need_to_use_this_value();
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: it's important
 note: the lint level is defined here
@@ -15,13 +15,13 @@ warning: unused return value of `MyStruct::need_to_use_this_method_value` that m
   --> $DIR/fn_must_use.rs:60:5
    |
 LL |     m.need_to_use_this_method_value();
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 warning: unused return value of `EvenNature::is_even` that must be used
   --> $DIR/fn_must_use.rs:61:5
    |
 LL |     m.is_even(); // trait method!
-   |     ^^^^^^^^^^^^
+   |     ^^^^^^^^^^^
    |
    = note: no side effects
 
@@ -29,19 +29,19 @@ warning: unused return value of `MyStruct::need_to_use_this_associated_function_
   --> $DIR/fn_must_use.rs:64:5
    |
 LL |     MyStruct::need_to_use_this_associated_function_value();
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 warning: unused return value of `std::cmp::PartialEq::eq` that must be used
   --> $DIR/fn_must_use.rs:70:5
    |
 LL |     2.eq(&3);
-   |     ^^^^^^^^^
+   |     ^^^^^^^^
 
 warning: unused return value of `std::cmp::PartialEq::eq` that must be used
   --> $DIR/fn_must_use.rs:71:5
    |
 LL |     m.eq(&n);
-   |     ^^^^^^^^^
+   |     ^^^^^^^^
 
 warning: unused comparison that must be used
   --> $DIR/fn_must_use.rs:74:5
diff --git a/src/test/ui/lint/inline-trait-and-foreign-items.stderr b/src/test/ui/lint/inline-trait-and-foreign-items.stderr
index 27399746bed6..2f1fb4c46c08 100644
--- a/src/test/ui/lint/inline-trait-and-foreign-items.stderr
+++ b/src/test/ui/lint/inline-trait-and-foreign-items.stderr
@@ -67,7 +67,7 @@ error: unconstrained opaque type
 LL |     type U = impl Trait;
    |              ^^^^^^^^^^
    |
-   = note: `U` must be used in combination with a concrete type within the same module
+   = note: `U` must be used in combination with a concrete type within the same impl
 
 error: aborting due to 6 previous errors; 2 warnings emitted
 
diff --git a/src/test/ui/lint/issue-103317.fixed b/src/test/ui/lint/issue-103317.fixed
new file mode 100644
index 000000000000..5a987423e5b9
--- /dev/null
+++ b/src/test/ui/lint/issue-103317.fixed
@@ -0,0 +1,14 @@
+// check-pass
+// run-rustfix
+
+#[warn(unreachable_pub)]
+mod inner {
+    #[allow(unused)]
+    pub(crate) enum T {
+        //~^ WARN unreachable `pub` item
+        A(u8),
+        X { a: f32, b: () },
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/lint/issue-103317.rs b/src/test/ui/lint/issue-103317.rs
new file mode 100644
index 000000000000..c2ba939e13c6
--- /dev/null
+++ b/src/test/ui/lint/issue-103317.rs
@@ -0,0 +1,14 @@
+// check-pass
+// run-rustfix
+
+#[warn(unreachable_pub)]
+mod inner {
+    #[allow(unused)]
+    pub enum T {
+        //~^ WARN unreachable `pub` item
+        A(u8),
+        X { a: f32, b: () },
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/lint/issue-103317.stderr b/src/test/ui/lint/issue-103317.stderr
new file mode 100644
index 000000000000..9c982ddc3464
--- /dev/null
+++ b/src/test/ui/lint/issue-103317.stderr
@@ -0,0 +1,17 @@
+warning: unreachable `pub` item
+  --> $DIR/issue-103317.rs:7:5
+   |
+LL |     pub enum T {
+   |     ---^^^^^^^
+   |     |
+   |     help: consider restricting its visibility: `pub(crate)`
+   |
+   = help: or consider exporting it for use by other crates
+note: the lint level is defined here
+  --> $DIR/issue-103317.rs:4:8
+   |
+LL | #[warn(unreachable_pub)]
+   |        ^^^^^^^^^^^^^^^
+
+warning: 1 warning emitted
+
diff --git a/src/test/ui/lint/issue-103435-extra-parentheses.fixed b/src/test/ui/lint/issue-103435-extra-parentheses.fixed
new file mode 100644
index 000000000000..2b01b414baa6
--- /dev/null
+++ b/src/test/ui/lint/issue-103435-extra-parentheses.fixed
@@ -0,0 +1,18 @@
+// run-rustfix
+#![deny(unused_parens)]
+
+fn main() {
+    if let Some(_) = Some(1) {}
+    //~^ ERROR unnecessary parentheses around pattern
+
+    for _x in 1..10 {}
+    //~^ ERROR unnecessary parentheses around pattern
+
+    if 2 == 1 {}
+    //~^ ERROR unnecessary parentheses around `if` condition
+
+    // reported by parser
+    for _x in 1..10 {}
+    //~^ ERROR expected one of
+    //~| ERROR unexpected parentheses surrounding
+}
diff --git a/src/test/ui/lint/issue-103435-extra-parentheses.rs b/src/test/ui/lint/issue-103435-extra-parentheses.rs
new file mode 100644
index 000000000000..8261610cf564
--- /dev/null
+++ b/src/test/ui/lint/issue-103435-extra-parentheses.rs
@@ -0,0 +1,18 @@
+// run-rustfix
+#![deny(unused_parens)]
+
+fn main() {
+    if let(Some(_))= Some(1) {}
+    //~^ ERROR unnecessary parentheses around pattern
+
+    for(_x)in 1..10 {}
+    //~^ ERROR unnecessary parentheses around pattern
+
+    if(2 == 1){}
+    //~^ ERROR unnecessary parentheses around `if` condition
+
+    // reported by parser
+    for(_x in 1..10){}
+    //~^ ERROR expected one of
+    //~| ERROR unexpected parentheses surrounding
+}
diff --git a/src/test/ui/lint/issue-103435-extra-parentheses.stderr b/src/test/ui/lint/issue-103435-extra-parentheses.stderr
new file mode 100644
index 000000000000..29c41c91050b
--- /dev/null
+++ b/src/test/ui/lint/issue-103435-extra-parentheses.stderr
@@ -0,0 +1,61 @@
+error: expected one of `)`, `,`, `@`, or `|`, found keyword `in`
+  --> $DIR/issue-103435-extra-parentheses.rs:15:12
+   |
+LL |     for(_x in 1..10){}
+   |            ^^ expected one of `)`, `,`, `@`, or `|`
+
+error: unexpected parentheses surrounding `for` loop head
+  --> $DIR/issue-103435-extra-parentheses.rs:15:8
+   |
+LL |     for(_x in 1..10){}
+   |        ^           ^
+   |
+help: remove parentheses in `for` loop
+   |
+LL -     for(_x in 1..10){}
+LL +     for _x in 1..10 {}
+   |
+
+error: unnecessary parentheses around pattern
+  --> $DIR/issue-103435-extra-parentheses.rs:5:11
+   |
+LL |     if let(Some(_))= Some(1) {}
+   |           ^       ^
+   |
+note: the lint level is defined here
+  --> $DIR/issue-103435-extra-parentheses.rs:2:9
+   |
+LL | #![deny(unused_parens)]
+   |         ^^^^^^^^^^^^^
+help: remove these parentheses
+   |
+LL -     if let(Some(_))= Some(1) {}
+LL +     if let Some(_) = Some(1) {}
+   |
+
+error: unnecessary parentheses around pattern
+  --> $DIR/issue-103435-extra-parentheses.rs:8:8
+   |
+LL |     for(_x)in 1..10 {}
+   |        ^  ^
+   |
+help: remove these parentheses
+   |
+LL -     for(_x)in 1..10 {}
+LL +     for _x in 1..10 {}
+   |
+
+error: unnecessary parentheses around `if` condition
+  --> $DIR/issue-103435-extra-parentheses.rs:11:7
+   |
+LL |     if(2 == 1){}
+   |       ^      ^
+   |
+help: remove these parentheses
+   |
+LL -     if(2 == 1){}
+LL +     if 2 == 1 {}
+   |
+
+error: aborting due to 5 previous errors
+
diff --git a/src/test/ui/lint/lint-incoherent-auto-trait-objects.stderr b/src/test/ui/lint/lint-incoherent-auto-trait-objects.stderr
index 2cc4d382d9df..553ab3869b33 100644
--- a/src/test/ui/lint/lint-incoherent-auto-trait-objects.stderr
+++ b/src/test/ui/lint/lint-incoherent-auto-trait-objects.stderr
@@ -1,36 +1,36 @@
-error: conflicting implementations of trait `Foo` for type `(dyn std::marker::Send + 'static)`: (E0119)
+error: conflicting implementations of trait `Foo` for type `(dyn Send + 'static)`: (E0119)
   --> $DIR/lint-incoherent-auto-trait-objects.rs:5:1
    |
 LL | impl Foo for dyn Send {}
    | --------------------- first implementation here
 LL |
 LL | impl Foo for dyn Send + Send {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + 'static)`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn Send + 'static)`
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #56484 <https://github.com/rust-lang/rust/issues/56484>
    = note: `#[deny(order_dependent_trait_objects)]` on by default
 
-error: conflicting implementations of trait `Foo` for type `(dyn std::marker::Send + std::marker::Sync + 'static)`: (E0119)
+error: conflicting implementations of trait `Foo` for type `(dyn Send + Sync + 'static)`: (E0119)
   --> $DIR/lint-incoherent-auto-trait-objects.rs:11:1
    |
 LL | impl Foo for dyn Send + Sync {}
    | ---------------------------- first implementation here
 LL |
 LL | impl Foo for dyn Sync + Send {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + std::marker::Sync + 'static)`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn Send + Sync + 'static)`
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #56484 <https://github.com/rust-lang/rust/issues/56484>
 
-error: conflicting implementations of trait `Foo` for type `(dyn std::marker::Send + std::marker::Sync + 'static)`: (E0119)
+error: conflicting implementations of trait `Foo` for type `(dyn Send + Sync + 'static)`: (E0119)
   --> $DIR/lint-incoherent-auto-trait-objects.rs:15:1
    |
 LL | impl Foo for dyn Sync + Send {}
    | ---------------------------- first implementation here
 ...
 LL | impl Foo for dyn Send + Sync + Send {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + std::marker::Sync + 'static)`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn Send + Sync + 'static)`
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #56484 <https://github.com/rust-lang/rust/issues/56484>
@@ -38,42 +38,42 @@ LL | impl Foo for dyn Send + Sync + Send {}
 error: aborting due to 3 previous errors
 
 Future incompatibility report: Future breakage diagnostic:
-error: conflicting implementations of trait `Foo` for type `(dyn std::marker::Send + 'static)`: (E0119)
+error: conflicting implementations of trait `Foo` for type `(dyn Send + 'static)`: (E0119)
   --> $DIR/lint-incoherent-auto-trait-objects.rs:5:1
    |
 LL | impl Foo for dyn Send {}
    | --------------------- first implementation here
 LL |
 LL | impl Foo for dyn Send + Send {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + 'static)`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn Send + 'static)`
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #56484 <https://github.com/rust-lang/rust/issues/56484>
    = note: `#[deny(order_dependent_trait_objects)]` on by default
 
 Future breakage diagnostic:
-error: conflicting implementations of trait `Foo` for type `(dyn std::marker::Send + std::marker::Sync + 'static)`: (E0119)
+error: conflicting implementations of trait `Foo` for type `(dyn Send + Sync + 'static)`: (E0119)
   --> $DIR/lint-incoherent-auto-trait-objects.rs:11:1
    |
 LL | impl Foo for dyn Send + Sync {}
    | ---------------------------- first implementation here
 LL |
 LL | impl Foo for dyn Sync + Send {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + std::marker::Sync + 'static)`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn Send + Sync + 'static)`
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #56484 <https://github.com/rust-lang/rust/issues/56484>
    = note: `#[deny(order_dependent_trait_objects)]` on by default
 
 Future breakage diagnostic:
-error: conflicting implementations of trait `Foo` for type `(dyn std::marker::Send + std::marker::Sync + 'static)`: (E0119)
+error: conflicting implementations of trait `Foo` for type `(dyn Send + Sync + 'static)`: (E0119)
   --> $DIR/lint-incoherent-auto-trait-objects.rs:15:1
    |
 LL | impl Foo for dyn Sync + Send {}
    | ---------------------------- first implementation here
 ...
 LL | impl Foo for dyn Send + Sync + Send {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + std::marker::Sync + 'static)`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn Send + Sync + 'static)`
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #56484 <https://github.com/rust-lang/rust/issues/56484>
diff --git a/src/test/ui/lint/no-coverage.stderr b/src/test/ui/lint/no-coverage.stderr
index 8452ccc7a03c..404efbeac1e1 100644
--- a/src/test/ui/lint/no-coverage.stderr
+++ b/src/test/ui/lint/no-coverage.stderr
@@ -94,7 +94,7 @@ error: unconstrained opaque type
 LL |     type U = impl Trait;
    |              ^^^^^^^^^^
    |
-   = note: `U` must be used in combination with a concrete type within the same module
+   = note: `U` must be used in combination with a concrete type within the same impl
 
 error: aborting due to 7 previous errors; 6 warnings emitted
 
diff --git a/src/test/ui/lint/opaque-ty-ffi-normalization-cycle.rs b/src/test/ui/lint/opaque-ty-ffi-normalization-cycle.rs
new file mode 100644
index 000000000000..c83bca4a4c57
--- /dev/null
+++ b/src/test/ui/lint/opaque-ty-ffi-normalization-cycle.rs
@@ -0,0 +1,41 @@
+#![feature(type_alias_impl_trait)]
+#![allow(unused)]
+#![deny(improper_ctypes)]
+
+pub trait TraitA {
+    type Assoc;
+}
+
+impl TraitA for u32 {
+    type Assoc = u32;
+}
+
+pub trait TraitB {
+    type Assoc;
+}
+
+impl<T> TraitB for T
+where
+    T: TraitA,
+{
+    type Assoc = <T as TraitA>::Assoc;
+}
+
+type AliasA = impl TraitA<Assoc = u32>;
+
+type AliasB = impl TraitB;
+
+fn use_of_a() -> AliasA {
+    3
+}
+
+fn use_of_b() -> AliasB {
+    3
+}
+
+extern "C" {
+    fn lint_me() -> <AliasB as TraitB>::Assoc;
+    //~^ ERROR `extern` block uses type `AliasB`, which is not FFI-safe
+}
+
+fn main() {}
diff --git a/src/test/ui/lint/opaque-ty-ffi-normalization-cycle.stderr b/src/test/ui/lint/opaque-ty-ffi-normalization-cycle.stderr
new file mode 100644
index 000000000000..e8d696477ada
--- /dev/null
+++ b/src/test/ui/lint/opaque-ty-ffi-normalization-cycle.stderr
@@ -0,0 +1,15 @@
+error: `extern` block uses type `AliasB`, which is not FFI-safe
+  --> $DIR/opaque-ty-ffi-normalization-cycle.rs:37:21
+   |
+LL |     fn lint_me() -> <AliasB as TraitB>::Assoc;
+   |                     ^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
+   |
+   = note: opaque types have no C equivalent
+note: the lint level is defined here
+  --> $DIR/opaque-ty-ffi-normalization-cycle.rs:3:9
+   |
+LL | #![deny(improper_ctypes)]
+   |         ^^^^^^^^^^^^^^^
+
+error: aborting due to previous error
+
diff --git a/src/test/ui/lint/unused/must-use-box-from-raw.stderr b/src/test/ui/lint/unused/must-use-box-from-raw.stderr
index 011acc3bf5d6..72118275774d 100644
--- a/src/test/ui/lint/unused/must-use-box-from-raw.stderr
+++ b/src/test/ui/lint/unused/must-use-box-from-raw.stderr
@@ -2,7 +2,7 @@ warning: unused return value of `Box::<T>::from_raw` that must be used
   --> $DIR/must-use-box-from-raw.rs:8:5
    |
 LL |     Box::from_raw(ptr);
-   |     ^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^
    |
    = note: call `drop(from_raw(ptr))` if you intend to drop the `Box`
 note: the lint level is defined here
diff --git a/src/test/ui/lint/unused/must_use-array.stderr b/src/test/ui/lint/unused/must_use-array.stderr
index 45a5317fccc6..bba2b1ba078c 100644
--- a/src/test/ui/lint/unused/must_use-array.stderr
+++ b/src/test/ui/lint/unused/must_use-array.stderr
@@ -2,7 +2,7 @@ error: unused array of `S` that must be used
   --> $DIR/must_use-array.rs:39:5
    |
 LL |     singleton();
-   |     ^^^^^^^^^^^^
+   |     ^^^^^^^^^^^
    |
 note: the lint level is defined here
   --> $DIR/must_use-array.rs:1:9
@@ -14,7 +14,7 @@ error: unused array of `S` that must be used
   --> $DIR/must_use-array.rs:40:5
    |
 LL |     many();
-   |     ^^^^^^^
+   |     ^^^^^^
 
 error: unused array of `S` in tuple element 0 that must be used
   --> $DIR/must_use-array.rs:41:6
@@ -26,7 +26,7 @@ error: unused array of implementers of `T` that must be used
   --> $DIR/must_use-array.rs:42:5
    |
 LL |     array_of_impl_trait();
-   |     ^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^
 
 error: unused array of boxed `T` trait objects in tuple element 1 that must be used
   --> $DIR/must_use-array.rs:43:5
@@ -38,7 +38,7 @@ error: unused array of arrays of arrays of `S` that must be used
   --> $DIR/must_use-array.rs:45:5
    |
 LL |     array_of_arrays_of_arrays();
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: aborting due to 6 previous errors
 
diff --git a/src/test/ui/lint/unused/must_use-in-stdlib-traits.stderr b/src/test/ui/lint/unused/must_use-in-stdlib-traits.stderr
index f5199f43c74b..ef738708d5f4 100644
--- a/src/test/ui/lint/unused/must_use-in-stdlib-traits.stderr
+++ b/src/test/ui/lint/unused/must_use-in-stdlib-traits.stderr
@@ -2,7 +2,7 @@ error: unused implementer of `Iterator` that must be used
   --> $DIR/must_use-in-stdlib-traits.rs:42:4
    |
 LL |    iterator();
-   |    ^^^^^^^^^^^
+   |    ^^^^^^^^^^
    |
    = note: iterators are lazy and do nothing unless consumed
 note: the lint level is defined here
@@ -15,7 +15,7 @@ error: unused implementer of `Future` that must be used
   --> $DIR/must_use-in-stdlib-traits.rs:43:4
    |
 LL |    future();
-   |    ^^^^^^^^^
+   |    ^^^^^^^^
    |
    = note: futures do nothing unless you `.await` or poll them
 
@@ -23,7 +23,7 @@ error: unused implementer of `FnOnce` that must be used
   --> $DIR/must_use-in-stdlib-traits.rs:44:4
    |
 LL |    square_fn_once();
-   |    ^^^^^^^^^^^^^^^^^
+   |    ^^^^^^^^^^^^^^^^
    |
    = note: closures are lazy and do nothing unless called
 
@@ -31,7 +31,7 @@ error: unused implementer of `FnMut` that must be used
   --> $DIR/must_use-in-stdlib-traits.rs:45:4
    |
 LL |    square_fn_mut();
-   |    ^^^^^^^^^^^^^^^^
+   |    ^^^^^^^^^^^^^^^
    |
    = note: closures are lazy and do nothing unless called
 
@@ -39,7 +39,7 @@ error: unused implementer of `Fn` that must be used
   --> $DIR/must_use-in-stdlib-traits.rs:46:4
    |
 LL |    square_fn();
-   |    ^^^^^^^^^^^^
+   |    ^^^^^^^^^^^
    |
    = note: closures are lazy and do nothing unless called
 
diff --git a/src/test/ui/lint/unused/must_use-trait.stderr b/src/test/ui/lint/unused/must_use-trait.stderr
index a42eb8841789..2f5496484835 100644
--- a/src/test/ui/lint/unused/must_use-trait.stderr
+++ b/src/test/ui/lint/unused/must_use-trait.stderr
@@ -2,7 +2,7 @@ error: unused implementer of `Critical` that must be used
   --> $DIR/must_use-trait.rs:33:5
    |
 LL |     get_critical();
-   |     ^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^
    |
 note: the lint level is defined here
   --> $DIR/must_use-trait.rs:1:9
@@ -14,13 +14,13 @@ error: unused boxed `Critical` trait object that must be used
   --> $DIR/must_use-trait.rs:34:5
    |
 LL |     get_boxed_critical();
-   |     ^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^
 
 error: unused boxed boxed `Critical` trait object that must be used
   --> $DIR/must_use-trait.rs:35:5
    |
 LL |     get_nested_boxed_critical();
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: unused boxed `Critical` trait object in tuple element 1 that must be used
   --> $DIR/must_use-trait.rs:37:5
diff --git a/src/test/ui/lint/unused/must_use-unit.stderr b/src/test/ui/lint/unused/must_use-unit.stderr
index 7f25a1935086..9fcbc5074ea8 100644
--- a/src/test/ui/lint/unused/must_use-unit.stderr
+++ b/src/test/ui/lint/unused/must_use-unit.stderr
@@ -2,7 +2,7 @@ error: unused return value of `foo` that must be used
   --> $DIR/must_use-unit.rs:13:5
    |
 LL |     foo();
-   |     ^^^^^^
+   |     ^^^^^
    |
 note: the lint level is defined here
   --> $DIR/must_use-unit.rs:2:9
@@ -14,7 +14,7 @@ error: unused return value of `bar` that must be used
   --> $DIR/must_use-unit.rs:15:5
    |
 LL |     bar();
-   |     ^^^^^^
+   |     ^^^^^
 
 error: aborting due to 2 previous errors
 
diff --git a/src/test/ui/lint/unused/unused-async.rs b/src/test/ui/lint/unused/unused-async.rs
index 7d17af115737..4be93aa155ad 100644
--- a/src/test/ui/lint/unused/unused-async.rs
+++ b/src/test/ui/lint/unused/unused-async.rs
@@ -1,24 +1,43 @@
 // edition:2018
-// run-pass
-#![allow(dead_code)]
+#![deny(unused_must_use)]
+
 
 #[must_use]
-//~^ WARNING `must_use`
-async fn test() -> i32 {
+async fn foo() -> i32 {
     1
 }
 
+#[must_use]
+fn bar() -> impl std::future::Future<Output=i32> {
+    async {
+        42
+    }
+}
+
+async fn baz() -> i32 {
+    0
+}
 
 struct Wowee {}
 
 impl Wowee {
     #[must_use]
-    //~^ WARNING `must_use`
     async fn test_method() -> i32 {
         1
     }
 }
 
+async fn test() {
+    foo(); //~ ERROR unused return value of `foo` that must be used
+    //~^ ERROR unused implementer of `Future` that must be used
+    foo().await; //~ ERROR unused output of future returned by `foo` that must be used
+    bar(); //~ ERROR unused return value of `bar` that must be used
+    //~^ ERROR unused implementer of `Future` that must be used
+    bar().await; //~ ERROR unused output of future returned by `bar` that must be used
+    baz(); //~ ERROR unused implementer of `Future` that must be used
+    baz().await; // ok
+}
+
 /* FIXME(guswynn) update this test when async-fn-in-traits works
 trait Doer {
     #[must_use]
diff --git a/src/test/ui/lint/unused/unused-async.stderr b/src/test/ui/lint/unused/unused-async.stderr
index 6bbc9e2bf008..4bcb26dc1658 100644
--- a/src/test/ui/lint/unused/unused-async.stderr
+++ b/src/test/ui/lint/unused/unused-async.stderr
@@ -1,26 +1,55 @@
-warning: `must_use` attribute on `async` functions applies to the anonymous `Future` returned by the function, not the value within
-  --> $DIR/unused-async.rs:5:1
+error: unused implementer of `Future` that must be used
+  --> $DIR/unused-async.rs:31:5
    |
-LL |   #[must_use]
-   |   ^^^^^^^^^^^
-LL |
-LL | / async fn test() -> i32 {
-LL | |     1
-LL | | }
-   | |_- this attribute does nothing, the `Future`s returned by async functions are already `must_use`
+LL |     foo();
+   |     ^^^^^
    |
-   = note: `#[warn(unused_attributes)]` on by default
-
-warning: `must_use` attribute on `async` functions applies to the anonymous `Future` returned by the function, not the value within
-  --> $DIR/unused-async.rs:15:5
+   = note: futures do nothing unless you `.await` or poll them
+note: the lint level is defined here
+  --> $DIR/unused-async.rs:2:9
    |
-LL |       #[must_use]
-   |       ^^^^^^^^^^^
-LL |
-LL | /     async fn test_method() -> i32 {
-LL | |         1
-LL | |     }
-   | |_____- this attribute does nothing, the `Future`s returned by async functions are already `must_use`
+LL | #![deny(unused_must_use)]
+   |         ^^^^^^^^^^^^^^^
 
-warning: 2 warnings emitted
+error: unused return value of `foo` that must be used
+  --> $DIR/unused-async.rs:31:5
+   |
+LL |     foo();
+   |     ^^^^^
+
+error: unused output of future returned by `foo` that must be used
+  --> $DIR/unused-async.rs:33:5
+   |
+LL |     foo().await;
+   |     ^^^^^^^^^^^
+
+error: unused implementer of `Future` that must be used
+  --> $DIR/unused-async.rs:34:5
+   |
+LL |     bar();
+   |     ^^^^^
+   |
+   = note: futures do nothing unless you `.await` or poll them
+
+error: unused return value of `bar` that must be used
+  --> $DIR/unused-async.rs:34:5
+   |
+LL |     bar();
+   |     ^^^^^
+
+error: unused output of future returned by `bar` that must be used
+  --> $DIR/unused-async.rs:36:5
+   |
+LL |     bar().await;
+   |     ^^^^^^^^^^^
+
+error: unused implementer of `Future` that must be used
+  --> $DIR/unused-async.rs:37:5
+   |
+LL |     baz();
+   |     ^^^^^
+   |
+   = note: futures do nothing unless you `.await` or poll them
+
+error: aborting due to 7 previous errors
 
diff --git a/src/test/ui/lint/unused/unused-closure.stderr b/src/test/ui/lint/unused/unused-closure.stderr
index 4362abd2037f..c3a82402e0a2 100644
--- a/src/test/ui/lint/unused/unused-closure.stderr
+++ b/src/test/ui/lint/unused/unused-closure.stderr
@@ -4,7 +4,7 @@ error: unused closure that must be used
 LL | /     || {
 LL | |         println!("Hello!");
 LL | |     };
-   | |______^
+   | |_____^
    |
    = note: closures are lazy and do nothing unless called
 note: the lint level is defined here
@@ -17,7 +17,7 @@ error: unused implementer of `Future` that must be used
   --> $DIR/unused-closure.rs:13:5
    |
 LL |     async {};
-   |     ^^^^^^^^^
+   |     ^^^^^^^^
    |
    = note: futures do nothing unless you `.await` or poll them
 
@@ -25,7 +25,7 @@ error: unused closure that must be used
   --> $DIR/unused-closure.rs:14:5
    |
 LL |     || async {};
-   |     ^^^^^^^^^^^^
+   |     ^^^^^^^^^^^
    |
    = note: closures are lazy and do nothing unless called
 
@@ -33,7 +33,7 @@ error: unused closure that must be used
   --> $DIR/unused-closure.rs:15:5
    |
 LL |     async || {};
-   |     ^^^^^^^^^^^^
+   |     ^^^^^^^^^^^
    |
    = note: closures are lazy and do nothing unless called
 
@@ -41,7 +41,7 @@ error: unused array of boxed arrays of closures that must be used
   --> $DIR/unused-closure.rs:18:5
    |
 LL |     [Box::new([|| {}; 10]); 1];
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: closures are lazy and do nothing unless called
 
@@ -49,7 +49,7 @@ error: unused closure that must be used
   --> $DIR/unused-closure.rs:20:5
    |
 LL |     vec![|| "a"].pop().unwrap();
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: closures are lazy and do nothing unless called
 
@@ -57,7 +57,7 @@ error: unused closure that must be used
   --> $DIR/unused-closure.rs:23:9
    |
 LL |         || true;
-   |         ^^^^^^^^
+   |         ^^^^^^^
    |
    = note: closures are lazy and do nothing unless called
 
diff --git a/src/test/ui/lint/unused/unused-result.stderr b/src/test/ui/lint/unused/unused-result.stderr
index 087e06341cdd..4e1ba1fd9595 100644
--- a/src/test/ui/lint/unused/unused-result.stderr
+++ b/src/test/ui/lint/unused/unused-result.stderr
@@ -2,7 +2,7 @@ error: unused `MustUse` that must be used
   --> $DIR/unused-result.rs:21:5
    |
 LL |     foo::<MustUse>();
-   |     ^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^
    |
 note: the lint level is defined here
   --> $DIR/unused-result.rs:2:25
@@ -14,7 +14,7 @@ error: unused `MustUseMsg` that must be used
   --> $DIR/unused-result.rs:22:5
    |
 LL |     foo::<MustUseMsg>();
-   |     ^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^
    |
    = note: some message
 
@@ -34,13 +34,13 @@ error: unused `MustUse` that must be used
   --> $DIR/unused-result.rs:35:5
    |
 LL |     foo::<MustUse>();
-   |     ^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^
 
 error: unused `MustUseMsg` that must be used
   --> $DIR/unused-result.rs:36:5
    |
 LL |     foo::<MustUseMsg>();
-   |     ^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^
    |
    = note: some message
 
diff --git a/src/test/ui/lint/unused/unused-supertrait.stderr b/src/test/ui/lint/unused/unused-supertrait.stderr
index d2f8c0078481..cb45add9c2b1 100644
--- a/src/test/ui/lint/unused/unused-supertrait.stderr
+++ b/src/test/ui/lint/unused/unused-supertrait.stderr
@@ -2,7 +2,7 @@ error: unused implementer of `Iterator` that must be used
   --> $DIR/unused-supertrait.rs:9:5
    |
 LL |     it();
-   |     ^^^^^
+   |     ^^^^
    |
    = note: iterators are lazy and do nothing unless consumed
 note: the lint level is defined here
diff --git a/src/test/ui/lint/unused/unused_attributes-must_use.stderr b/src/test/ui/lint/unused/unused_attributes-must_use.stderr
index ce959ddbc469..0f699429e024 100644
--- a/src/test/ui/lint/unused/unused_attributes-must_use.stderr
+++ b/src/test/ui/lint/unused/unused_attributes-must_use.stderr
@@ -139,7 +139,7 @@ error: unused `X` that must be used
   --> $DIR/unused_attributes-must_use.rs:103:5
    |
 LL |     X;
-   |     ^^
+   |     ^
    |
 note: the lint level is defined here
   --> $DIR/unused_attributes-must_use.rs:2:28
@@ -151,37 +151,37 @@ error: unused `Y` that must be used
   --> $DIR/unused_attributes-must_use.rs:104:5
    |
 LL |     Y::Z;
-   |     ^^^^^
+   |     ^^^^
 
 error: unused `U` that must be used
   --> $DIR/unused_attributes-must_use.rs:105:5
    |
 LL |     U { unit: () };
-   |     ^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^
 
 error: unused return value of `U::method` that must be used
   --> $DIR/unused_attributes-must_use.rs:106:5
    |
 LL |     U::method();
-   |     ^^^^^^^^^^^^
+   |     ^^^^^^^^^^^
 
 error: unused return value of `foo` that must be used
   --> $DIR/unused_attributes-must_use.rs:107:5
    |
 LL |     foo();
-   |     ^^^^^^
+   |     ^^^^^
 
 error: unused return value of `foreign_foo` that must be used
   --> $DIR/unused_attributes-must_use.rs:110:9
    |
 LL |         foreign_foo();
-   |         ^^^^^^^^^^^^^^
+   |         ^^^^^^^^^^^^^
 
 error: unused return value of `Use::get_four` that must be used
   --> $DIR/unused_attributes-must_use.rs:118:5
    |
 LL |     ().get_four();
-   |     ^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^
 
 error: aborting due to 28 previous errors
 
diff --git a/src/test/ui/macros/assert-trailing-junk.with-generic-asset.stderr b/src/test/ui/macros/assert-trailing-junk.with-generic-asset.stderr
index 09dd16a0b0d8..1e73320e4391 100644
--- a/src/test/ui/macros/assert-trailing-junk.with-generic-asset.stderr
+++ b/src/test/ui/macros/assert-trailing-junk.with-generic-asset.stderr
@@ -17,6 +17,8 @@ LL |     assert!(true, "whatever" blah);
    |                             -^^^^ no rules expected this token in macro call
    |                             |
    |                             help: missing comma here
+   |
+   = note: while trying to match sequence start
 
 error: unexpected string literal
   --> $DIR/assert-trailing-junk.rs:18:18
@@ -33,6 +35,8 @@ LL |     assert!(true "whatever" blah);
    |                            -^^^^ no rules expected this token in macro call
    |                            |
    |                            help: missing comma here
+   |
+   = note: while trying to match sequence start
 
 error: macro requires an expression as an argument
   --> $DIR/assert-trailing-junk.rs:22:5
diff --git a/src/test/ui/macros/assert-trailing-junk.without-generic-asset.stderr b/src/test/ui/macros/assert-trailing-junk.without-generic-asset.stderr
index 09dd16a0b0d8..1e73320e4391 100644
--- a/src/test/ui/macros/assert-trailing-junk.without-generic-asset.stderr
+++ b/src/test/ui/macros/assert-trailing-junk.without-generic-asset.stderr
@@ -17,6 +17,8 @@ LL |     assert!(true, "whatever" blah);
    |                             -^^^^ no rules expected this token in macro call
    |                             |
    |                             help: missing comma here
+   |
+   = note: while trying to match sequence start
 
 error: unexpected string literal
   --> $DIR/assert-trailing-junk.rs:18:18
@@ -33,6 +35,8 @@ LL |     assert!(true "whatever" blah);
    |                            -^^^^ no rules expected this token in macro call
    |                            |
    |                            help: missing comma here
+   |
+   = note: while trying to match sequence start
 
 error: macro requires an expression as an argument
   --> $DIR/assert-trailing-junk.rs:22:5
diff --git a/src/test/ui/attr-from-macro.rs b/src/test/ui/macros/attr-from-macro.rs
similarity index 100%
rename from src/test/ui/attr-from-macro.rs
rename to src/test/ui/macros/attr-from-macro.rs
diff --git a/src/test/ui/auxiliary/attr-from-macro.rs b/src/test/ui/macros/auxiliary/attr-from-macro.rs
similarity index 100%
rename from src/test/ui/auxiliary/attr-from-macro.rs
rename to src/test/ui/macros/auxiliary/attr-from-macro.rs
diff --git a/src/test/ui/macros/issue-38715.rs b/src/test/ui/macros/issue-38715.rs
index 9a9a501cae15..85ed97663e8a 100644
--- a/src/test/ui/macros/issue-38715.rs
+++ b/src/test/ui/macros/issue-38715.rs
@@ -1,7 +1,17 @@
 #[macro_export]
-macro_rules! foo { ($i:ident) => {} }
+macro_rules! foo { () => {} }
 
 #[macro_export]
 macro_rules! foo { () => {} } //~ ERROR the name `foo` is defined multiple times
 
+mod inner1 {
+    #[macro_export]
+    macro_rules! bar { () => {} }
+}
+
+mod inner2 {
+    #[macro_export]
+    macro_rules! bar { () => {} } //~ ERROR the name `bar` is defined multiple times
+}
+
 fn main() {}
diff --git a/src/test/ui/macros/issue-38715.stderr b/src/test/ui/macros/issue-38715.stderr
index c87d9f7360b9..828a7f459301 100644
--- a/src/test/ui/macros/issue-38715.stderr
+++ b/src/test/ui/macros/issue-38715.stderr
@@ -1,7 +1,7 @@
 error[E0428]: the name `foo` is defined multiple times
   --> $DIR/issue-38715.rs:5:1
    |
-LL | macro_rules! foo { ($i:ident) => {} }
+LL | macro_rules! foo { () => {} }
    | ---------------- previous definition of the macro `foo` here
 ...
 LL | macro_rules! foo { () => {} }
@@ -9,6 +9,17 @@ LL | macro_rules! foo { () => {} }
    |
    = note: `foo` must be defined only once in the macro namespace of this module
 
-error: aborting due to previous error
+error[E0428]: the name `bar` is defined multiple times
+  --> $DIR/issue-38715.rs:14:5
+   |
+LL |     macro_rules! bar { () => {} }
+   |     ---------------- previous definition of the macro `bar` here
+...
+LL |     macro_rules! bar { () => {} }
+   |     ^^^^^^^^^^^^^^^^ `bar` redefined here
+   |
+   = note: `bar` must be defined only once in the macro namespace of this module
+
+error: aborting due to 2 previous errors
 
 For more information about this error, try `rustc --explain E0428`.
diff --git a/src/test/ui/macros/macro-at-most-once-rep-2015.stderr b/src/test/ui/macros/macro-at-most-once-rep-2015.stderr
index 9a3df858e515..7c45b85bc8d4 100644
--- a/src/test/ui/macros/macro-at-most-once-rep-2015.stderr
+++ b/src/test/ui/macros/macro-at-most-once-rep-2015.stderr
@@ -12,6 +12,8 @@ LL | macro_rules! foo {
 ...
 LL |     foo!(a?);
    |           ^ no rules expected this token in macro call
+   |
+   = note: while trying to match sequence end
 
 error: no rules expected the token `?`
   --> $DIR/macro-at-most-once-rep-2015.rs:26:11
@@ -21,6 +23,8 @@ LL | macro_rules! foo {
 ...
 LL |     foo!(a?a);
    |           ^ no rules expected this token in macro call
+   |
+   = note: while trying to match sequence end
 
 error: no rules expected the token `?`
   --> $DIR/macro-at-most-once-rep-2015.rs:27:11
@@ -30,6 +34,8 @@ LL | macro_rules! foo {
 ...
 LL |     foo!(a?a?a);
    |           ^ no rules expected this token in macro call
+   |
+   = note: while trying to match sequence end
 
 error: unexpected end of macro invocation
   --> $DIR/macro-at-most-once-rep-2015.rs:29:5
@@ -39,6 +45,12 @@ LL | macro_rules! barplus {
 ...
 LL |     barplus!();
    |     ^^^^^^^^^^ missing tokens in macro arguments
+   |
+note: while trying to match `+`
+  --> $DIR/macro-at-most-once-rep-2015.rs:15:11
+   |
+LL |     ($(a)?+) => {}; // ok. matches "a+" and "+"
+   |           ^
 
 error: unexpected end of macro invocation
   --> $DIR/macro-at-most-once-rep-2015.rs:30:15
@@ -48,6 +60,12 @@ LL | macro_rules! barplus {
 ...
 LL |     barplus!(a);
    |               ^ missing tokens in macro arguments
+   |
+note: while trying to match `+`
+  --> $DIR/macro-at-most-once-rep-2015.rs:15:11
+   |
+LL |     ($(a)?+) => {}; // ok. matches "a+" and "+"
+   |           ^
 
 error: no rules expected the token `?`
   --> $DIR/macro-at-most-once-rep-2015.rs:31:15
@@ -57,6 +75,12 @@ LL | macro_rules! barplus {
 ...
 LL |     barplus!(a?);
    |               ^ no rules expected this token in macro call
+   |
+note: while trying to match `+`
+  --> $DIR/macro-at-most-once-rep-2015.rs:15:11
+   |
+LL |     ($(a)?+) => {}; // ok. matches "a+" and "+"
+   |           ^
 
 error: no rules expected the token `?`
   --> $DIR/macro-at-most-once-rep-2015.rs:32:15
@@ -66,6 +90,12 @@ LL | macro_rules! barplus {
 ...
 LL |     barplus!(a?a);
    |               ^ no rules expected this token in macro call
+   |
+note: while trying to match `+`
+  --> $DIR/macro-at-most-once-rep-2015.rs:15:11
+   |
+LL |     ($(a)?+) => {}; // ok. matches "a+" and "+"
+   |           ^
 
 error: unexpected end of macro invocation
   --> $DIR/macro-at-most-once-rep-2015.rs:36:5
@@ -75,6 +105,12 @@ LL | macro_rules! barstar {
 ...
 LL |     barstar!();
    |     ^^^^^^^^^^ missing tokens in macro arguments
+   |
+note: while trying to match `*`
+  --> $DIR/macro-at-most-once-rep-2015.rs:19:11
+   |
+LL |     ($(a)?*) => {}; // ok. matches "a*" and "*"
+   |           ^
 
 error: unexpected end of macro invocation
   --> $DIR/macro-at-most-once-rep-2015.rs:37:15
@@ -84,6 +120,12 @@ LL | macro_rules! barstar {
 ...
 LL |     barstar!(a);
    |               ^ missing tokens in macro arguments
+   |
+note: while trying to match `*`
+  --> $DIR/macro-at-most-once-rep-2015.rs:19:11
+   |
+LL |     ($(a)?*) => {}; // ok. matches "a*" and "*"
+   |           ^
 
 error: no rules expected the token `?`
   --> $DIR/macro-at-most-once-rep-2015.rs:38:15
@@ -93,6 +135,12 @@ LL | macro_rules! barstar {
 ...
 LL |     barstar!(a?);
    |               ^ no rules expected this token in macro call
+   |
+note: while trying to match `*`
+  --> $DIR/macro-at-most-once-rep-2015.rs:19:11
+   |
+LL |     ($(a)?*) => {}; // ok. matches "a*" and "*"
+   |           ^
 
 error: no rules expected the token `?`
   --> $DIR/macro-at-most-once-rep-2015.rs:39:15
@@ -102,6 +150,12 @@ LL | macro_rules! barstar {
 ...
 LL |     barstar!(a?a);
    |               ^ no rules expected this token in macro call
+   |
+note: while trying to match `*`
+  --> $DIR/macro-at-most-once-rep-2015.rs:19:11
+   |
+LL |     ($(a)?*) => {}; // ok. matches "a*" and "*"
+   |           ^
 
 error: aborting due to 12 previous errors
 
diff --git a/src/test/ui/macros/macro-at-most-once-rep-2018.stderr b/src/test/ui/macros/macro-at-most-once-rep-2018.stderr
index 013fabe13e5f..696520b28268 100644
--- a/src/test/ui/macros/macro-at-most-once-rep-2018.stderr
+++ b/src/test/ui/macros/macro-at-most-once-rep-2018.stderr
@@ -12,6 +12,8 @@ LL | macro_rules! foo {
 ...
 LL |     foo!(a?);
    |           ^ no rules expected this token in macro call
+   |
+   = note: while trying to match sequence end
 
 error: no rules expected the token `?`
   --> $DIR/macro-at-most-once-rep-2018.rs:26:11
@@ -21,6 +23,8 @@ LL | macro_rules! foo {
 ...
 LL |     foo!(a?a);
    |           ^ no rules expected this token in macro call
+   |
+   = note: while trying to match sequence end
 
 error: no rules expected the token `?`
   --> $DIR/macro-at-most-once-rep-2018.rs:27:11
@@ -30,6 +34,8 @@ LL | macro_rules! foo {
 ...
 LL |     foo!(a?a?a);
    |           ^ no rules expected this token in macro call
+   |
+   = note: while trying to match sequence end
 
 error: unexpected end of macro invocation
   --> $DIR/macro-at-most-once-rep-2018.rs:29:5
@@ -39,6 +45,12 @@ LL | macro_rules! barplus {
 ...
 LL |     barplus!();
    |     ^^^^^^^^^^ missing tokens in macro arguments
+   |
+note: while trying to match `+`
+  --> $DIR/macro-at-most-once-rep-2018.rs:15:11
+   |
+LL |     ($(a)?+) => {}; // ok. matches "a+" and "+"
+   |           ^
 
 error: unexpected end of macro invocation
   --> $DIR/macro-at-most-once-rep-2018.rs:30:15
@@ -48,6 +60,12 @@ LL | macro_rules! barplus {
 ...
 LL |     barplus!(a);
    |               ^ missing tokens in macro arguments
+   |
+note: while trying to match `+`
+  --> $DIR/macro-at-most-once-rep-2018.rs:15:11
+   |
+LL |     ($(a)?+) => {}; // ok. matches "a+" and "+"
+   |           ^
 
 error: no rules expected the token `?`
   --> $DIR/macro-at-most-once-rep-2018.rs:31:15
@@ -57,6 +75,12 @@ LL | macro_rules! barplus {
 ...
 LL |     barplus!(a?);
    |               ^ no rules expected this token in macro call
+   |
+note: while trying to match `+`
+  --> $DIR/macro-at-most-once-rep-2018.rs:15:11
+   |
+LL |     ($(a)?+) => {}; // ok. matches "a+" and "+"
+   |           ^
 
 error: no rules expected the token `?`
   --> $DIR/macro-at-most-once-rep-2018.rs:32:15
@@ -66,6 +90,12 @@ LL | macro_rules! barplus {
 ...
 LL |     barplus!(a?a);
    |               ^ no rules expected this token in macro call
+   |
+note: while trying to match `+`
+  --> $DIR/macro-at-most-once-rep-2018.rs:15:11
+   |
+LL |     ($(a)?+) => {}; // ok. matches "a+" and "+"
+   |           ^
 
 error: unexpected end of macro invocation
   --> $DIR/macro-at-most-once-rep-2018.rs:36:5
@@ -75,6 +105,12 @@ LL | macro_rules! barstar {
 ...
 LL |     barstar!();
    |     ^^^^^^^^^^ missing tokens in macro arguments
+   |
+note: while trying to match `*`
+  --> $DIR/macro-at-most-once-rep-2018.rs:19:11
+   |
+LL |     ($(a)?*) => {}; // ok. matches "a*" and "*"
+   |           ^
 
 error: unexpected end of macro invocation
   --> $DIR/macro-at-most-once-rep-2018.rs:37:15
@@ -84,6 +120,12 @@ LL | macro_rules! barstar {
 ...
 LL |     barstar!(a);
    |               ^ missing tokens in macro arguments
+   |
+note: while trying to match `*`
+  --> $DIR/macro-at-most-once-rep-2018.rs:19:11
+   |
+LL |     ($(a)?*) => {}; // ok. matches "a*" and "*"
+   |           ^
 
 error: no rules expected the token `?`
   --> $DIR/macro-at-most-once-rep-2018.rs:38:15
@@ -93,6 +135,12 @@ LL | macro_rules! barstar {
 ...
 LL |     barstar!(a?);
    |               ^ no rules expected this token in macro call
+   |
+note: while trying to match `*`
+  --> $DIR/macro-at-most-once-rep-2018.rs:19:11
+   |
+LL |     ($(a)?*) => {}; // ok. matches "a*" and "*"
+   |           ^
 
 error: no rules expected the token `?`
   --> $DIR/macro-at-most-once-rep-2018.rs:39:15
@@ -102,6 +150,12 @@ LL | macro_rules! barstar {
 ...
 LL |     barstar!(a?a);
    |               ^ no rules expected this token in macro call
+   |
+note: while trying to match `*`
+  --> $DIR/macro-at-most-once-rep-2018.rs:19:11
+   |
+LL |     ($(a)?*) => {}; // ok. matches "a*" and "*"
+   |           ^
 
 error: aborting due to 12 previous errors
 
diff --git a/src/test/ui/macros/macro-non-lifetime.stderr b/src/test/ui/macros/macro-non-lifetime.stderr
index 6234735dfc8a..e1ed87f94355 100644
--- a/src/test/ui/macros/macro-non-lifetime.stderr
+++ b/src/test/ui/macros/macro-non-lifetime.stderr
@@ -6,6 +6,12 @@ LL | macro_rules! m { ($x:lifetime) => { } }
 ...
 LL |     m!(a);
    |        ^ no rules expected this token in macro call
+   |
+note: while trying to match meta-variable `$x:lifetime`
+  --> $DIR/macro-non-lifetime.rs:3:19
+   |
+LL | macro_rules! m { ($x:lifetime) => { } }
+   |                   ^^^^^^^^^^^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/macros/macro_rules-unmatchable-literals.rs b/src/test/ui/macros/macro_rules-unmatchable-literals.rs
new file mode 100644
index 000000000000..bde0fe1a0157
--- /dev/null
+++ b/src/test/ui/macros/macro_rules-unmatchable-literals.rs
@@ -0,0 +1,14 @@
+// Pinning tests for things that don't work to make sure we notice if that changes
+
+#![crate_type = "lib"]
+
+macro_rules! octal_with_bad_digit {
+    ( 0o1238 ) => {}; //~ ERROR invalid digit
+}
+
+macro_rules! binary_with_bad_digit {
+    ( 0b012 ) => {}; //~ ERROR invalid digit
+}
+
+// This can't happen for Hex and Decimal as things like `123A` and `0xFFG`
+// get treated as unknown *suffixes*, rather than digits.
diff --git a/src/test/ui/macros/macro_rules-unmatchable-literals.stderr b/src/test/ui/macros/macro_rules-unmatchable-literals.stderr
new file mode 100644
index 000000000000..956a669791d0
--- /dev/null
+++ b/src/test/ui/macros/macro_rules-unmatchable-literals.stderr
@@ -0,0 +1,14 @@
+error: invalid digit for a base 8 literal
+  --> $DIR/macro_rules-unmatchable-literals.rs:6:12
+   |
+LL |     ( 0o1238 ) => {};
+   |            ^
+
+error: invalid digit for a base 2 literal
+  --> $DIR/macro_rules-unmatchable-literals.rs:10:11
+   |
+LL |     ( 0b012 ) => {};
+   |           ^
+
+error: aborting due to 2 previous errors
+
diff --git a/src/test/ui/macros/macros-nonfatal-errors.rs b/src/test/ui/macros/macros-nonfatal-errors.rs
index 140cc5b0fd80..ab14c35893d0 100644
--- a/src/test/ui/macros/macros-nonfatal-errors.rs
+++ b/src/test/ui/macros/macros-nonfatal-errors.rs
@@ -4,7 +4,7 @@
 // immediately, so that we get more errors listed at a time.
 
 #![feature(trace_macros, concat_idents)]
-#![feature(stmt_expr_attributes, arbitrary_enum_discriminant)]
+#![feature(stmt_expr_attributes)]
 
 use std::arch::asm;
 
diff --git a/src/test/ui/macros/missing-comma.stderr b/src/test/ui/macros/missing-comma.stderr
index 6da92bdea19e..81877a29ed8a 100644
--- a/src/test/ui/macros/missing-comma.stderr
+++ b/src/test/ui/macros/missing-comma.stderr
@@ -14,6 +14,12 @@ LL |     foo!(a b);
    |           -^ no rules expected this token in macro call
    |           |
    |           help: missing comma here
+   |
+note: while trying to match meta-variable `$a:ident`
+  --> $DIR/missing-comma.rs:2:6
+   |
+LL |     ($a:ident) => ();
+   |      ^^^^^^^^
 
 error: no rules expected the token `e`
   --> $DIR/missing-comma.rs:23:21
@@ -25,6 +31,12 @@ LL |     foo!(a, b, c, d e);
    |                    -^ no rules expected this token in macro call
    |                    |
    |                    help: missing comma here
+   |
+note: while trying to match meta-variable `$d:ident`
+  --> $DIR/missing-comma.rs:5:36
+   |
+LL |     ($a:ident, $b:ident, $c:ident, $d:ident) => ();
+   |                                    ^^^^^^^^
 
 error: no rules expected the token `d`
   --> $DIR/missing-comma.rs:25:18
@@ -36,6 +48,12 @@ LL |     foo!(a, b, c d, e);
    |                 -^ no rules expected this token in macro call
    |                 |
    |                 help: missing comma here
+   |
+note: while trying to match meta-variable `$c:ident`
+  --> $DIR/missing-comma.rs:4:26
+   |
+LL |     ($a:ident, $b:ident, $c:ident) => ();
+   |                          ^^^^^^^^
 
 error: no rules expected the token `d`
   --> $DIR/missing-comma.rs:27:18
@@ -45,6 +63,12 @@ LL | macro_rules! foo {
 ...
 LL |     foo!(a, b, c d e);
    |                  ^ no rules expected this token in macro call
+   |
+note: while trying to match meta-variable `$c:ident`
+  --> $DIR/missing-comma.rs:4:26
+   |
+LL |     ($a:ident, $b:ident, $c:ident) => ();
+   |                          ^^^^^^^^
 
 error: unexpected end of macro invocation
   --> $DIR/missing-comma.rs:29:23
@@ -54,6 +78,12 @@ LL | macro_rules! bar {
 ...
 LL |     bar!(Level::Error, );
    |                       ^ missing tokens in macro arguments
+   |
+note: while trying to match meta-variable `$arg:tt`
+  --> $DIR/missing-comma.rs:10:19
+   |
+LL |     ($lvl:expr, $($arg:tt)+) => {}
+   |                   ^^^^^^^
 
 error: no rules expected the token `,`
   --> $DIR/missing-comma.rs:32:38
@@ -63,6 +93,12 @@ LL | macro_rules! check {
 ...
 LL |     check!(<str as Debug>::fmt, "fmt",);
    |                                      ^ no rules expected this token in macro call
+   |
+note: while trying to match meta-variable `$expected:expr`
+  --> $DIR/missing-comma.rs:14:14
+   |
+LL |     ($ty:ty, $expected:expr) => {};
+   |              ^^^^^^^^^^^^^^
 
 error: aborting due to 7 previous errors
 
diff --git a/src/test/ui/macros/nonterminal-matching.stderr b/src/test/ui/macros/nonterminal-matching.stderr
index 585f2355321f..5bbd54390983 100644
--- a/src/test/ui/macros/nonterminal-matching.stderr
+++ b/src/test/ui/macros/nonterminal-matching.stderr
@@ -10,6 +10,14 @@ LL |     n!(a $nt_item b);
 LL | complex_nonterminal!(enum E {});
    | ------------------------------- in this macro invocation
    |
+note: while trying to match `enum E {}`
+  --> $DIR/nonterminal-matching.rs:15:15
+   |
+LL |     macro n(a $nt_item b) {
+   |               ^^^^^^^^
+...
+LL | complex_nonterminal!(enum E {});
+   | ------------------------------- in this macro invocation
    = note: this error originates in the macro `complex_nonterminal` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error
diff --git a/src/test/ui/macros/trace_faulty_macros.stderr b/src/test/ui/macros/trace_faulty_macros.stderr
index d6fc69402144..21e47da07571 100644
--- a/src/test/ui/macros/trace_faulty_macros.stderr
+++ b/src/test/ui/macros/trace_faulty_macros.stderr
@@ -10,6 +10,7 @@ LL |         my_faulty_macro!(bcd);
 LL |     my_faulty_macro!();
    |     ------------------ in this macro invocation
    |
+   = note: while trying to match end of macro
    = note: this error originates in the macro `my_faulty_macro` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 note: trace_macro
diff --git a/src/test/ui/marker_trait_attr/overlap-marker-trait-with-static-lifetime.rs b/src/test/ui/marker_trait_attr/overlap-marker-trait-with-static-lifetime.rs
new file mode 100644
index 000000000000..62aa22d41ed8
--- /dev/null
+++ b/src/test/ui/marker_trait_attr/overlap-marker-trait-with-static-lifetime.rs
@@ -0,0 +1,10 @@
+// check-pass
+#![feature(marker_trait_attr)]
+
+#[marker]
+trait Marker {}
+
+impl Marker for &'static () {}
+impl Marker for &'static () {}
+
+fn main() {}
diff --git a/src/test/ui/marker_trait_attr/overlap-marker-trait-with-underscore-lifetime.rs b/src/test/ui/marker_trait_attr/overlap-marker-trait-with-underscore-lifetime.rs
new file mode 100644
index 000000000000..eabce1aeff14
--- /dev/null
+++ b/src/test/ui/marker_trait_attr/overlap-marker-trait-with-underscore-lifetime.rs
@@ -0,0 +1,9 @@
+#![feature(marker_trait_attr)]
+
+#[marker]
+trait Marker {}
+
+impl Marker for &'_ () {} //~ ERROR type annotations needed
+impl Marker for &'_ () {} //~ ERROR type annotations needed
+
+fn main() {}
diff --git a/src/test/ui/marker_trait_attr/overlap-marker-trait-with-underscore-lifetime.stderr b/src/test/ui/marker_trait_attr/overlap-marker-trait-with-underscore-lifetime.stderr
new file mode 100644
index 000000000000..235c89e200ae
--- /dev/null
+++ b/src/test/ui/marker_trait_attr/overlap-marker-trait-with-underscore-lifetime.stderr
@@ -0,0 +1,31 @@
+error[E0283]: type annotations needed: cannot satisfy `&(): Marker`
+  --> $DIR/overlap-marker-trait-with-underscore-lifetime.rs:6:6
+   |
+LL | impl Marker for &'_ () {}
+   |      ^^^^^^
+   |
+note: multiple `impl`s satisfying `&(): Marker` found
+  --> $DIR/overlap-marker-trait-with-underscore-lifetime.rs:6:1
+   |
+LL | impl Marker for &'_ () {}
+   | ^^^^^^^^^^^^^^^^^^^^^^
+LL | impl Marker for &'_ () {}
+   | ^^^^^^^^^^^^^^^^^^^^^^
+
+error[E0283]: type annotations needed: cannot satisfy `&(): Marker`
+  --> $DIR/overlap-marker-trait-with-underscore-lifetime.rs:7:6
+   |
+LL | impl Marker for &'_ () {}
+   |      ^^^^^^
+   |
+note: multiple `impl`s satisfying `&(): Marker` found
+  --> $DIR/overlap-marker-trait-with-underscore-lifetime.rs:6:1
+   |
+LL | impl Marker for &'_ () {}
+   | ^^^^^^^^^^^^^^^^^^^^^^
+LL | impl Marker for &'_ () {}
+   | ^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0283`.
diff --git a/src/test/ui/marker_trait_attr/overlap-marker-trait.rs b/src/test/ui/marker_trait_attr/overlap-marker-trait.rs
index 8794d42f4113..67e551797755 100644
--- a/src/test/ui/marker_trait_attr/overlap-marker-trait.rs
+++ b/src/test/ui/marker_trait_attr/overlap-marker-trait.rs
@@ -7,7 +7,8 @@
 
 use std::fmt::{Debug, Display};
 
-#[marker] trait Marker {}
+#[marker]
+trait Marker {}
 
 impl<T: Debug> Marker for T {}
 impl<T: Display> Marker for T {}
diff --git a/src/test/ui/marker_trait_attr/overlap-marker-trait.stderr b/src/test/ui/marker_trait_attr/overlap-marker-trait.stderr
index 1f3410597944..133bc0484ee0 100644
--- a/src/test/ui/marker_trait_attr/overlap-marker-trait.stderr
+++ b/src/test/ui/marker_trait_attr/overlap-marker-trait.stderr
@@ -1,11 +1,11 @@
 error[E0277]: the trait bound `NotDebugOrDisplay: Marker` is not satisfied
-  --> $DIR/overlap-marker-trait.rs:27:17
+  --> $DIR/overlap-marker-trait.rs:28:17
    |
 LL |     is_marker::<NotDebugOrDisplay>();
    |                 ^^^^^^^^^^^^^^^^^ the trait `Marker` is not implemented for `NotDebugOrDisplay`
    |
 note: required by a bound in `is_marker`
-  --> $DIR/overlap-marker-trait.rs:15:17
+  --> $DIR/overlap-marker-trait.rs:16:17
    |
 LL | fn is_marker<T: Marker>() { }
    |                 ^^^^^^ required by this bound in `is_marker`
diff --git a/src/test/ui/marker_trait_attr/overlap-permitted-for-annotated-marker-traits.rs b/src/test/ui/marker_trait_attr/overlap-permitted-for-annotated-marker-traits.rs
index 383313902379..f7654458feb0 100644
--- a/src/test/ui/marker_trait_attr/overlap-permitted-for-annotated-marker-traits.rs
+++ b/src/test/ui/marker_trait_attr/overlap-permitted-for-annotated-marker-traits.rs
@@ -7,7 +7,8 @@
 
 use std::fmt::{Debug, Display};
 
-#[marker] trait MyMarker {}
+#[marker]
+trait MyMarker {}
 
 impl<T: Debug> MyMarker for T {}
 impl<T: Display> MyMarker for T {}
diff --git a/src/test/ui/issues/issue-12552.rs b/src/test/ui/match/issue-12552.rs
similarity index 100%
rename from src/test/ui/issues/issue-12552.rs
rename to src/test/ui/match/issue-12552.rs
diff --git a/src/test/ui/issues/issue-12552.stderr b/src/test/ui/match/issue-12552.stderr
similarity index 100%
rename from src/test/ui/issues/issue-12552.stderr
rename to src/test/ui/match/issue-12552.stderr
diff --git a/src/test/ui/mismatched_types/unboxed-closures-vtable-mismatch.rs b/src/test/ui/mismatched_types/unboxed-closures-vtable-mismatch.rs
index 8dbe3472ea89..307104e47a18 100644
--- a/src/test/ui/mismatched_types/unboxed-closures-vtable-mismatch.rs
+++ b/src/test/ui/mismatched_types/unboxed-closures-vtable-mismatch.rs
@@ -1,8 +1,8 @@
-#![feature(unboxed_closures)]
+#![feature(unboxed_closures,tuple_trait)]
 
 use std::ops::FnMut;
 
-fn to_fn_mut<A, F: FnMut<A>>(f: F) -> F { f }
+fn to_fn_mut<A:std::marker::Tuple, F:FnMut<A>>(f: F) -> F { f }
 
 fn call_it<F: FnMut(isize, isize) -> isize>(y: isize, mut f: F) -> isize {
     //~^ NOTE required by this bound in `call_it`
diff --git a/src/test/ui/moves/moves-based-on-type-move-out-of-closure-env-issue-1965.rs b/src/test/ui/moves/moves-based-on-type-move-out-of-closure-env-issue-1965.rs
index 76b7aab542de..490d91ac118c 100644
--- a/src/test/ui/moves/moves-based-on-type-move-out-of-closure-env-issue-1965.rs
+++ b/src/test/ui/moves/moves-based-on-type-move-out-of-closure-env-issue-1965.rs
@@ -1,6 +1,6 @@
-#![feature(unboxed_closures)]
+#![feature(unboxed_closures, tuple_trait)]
 
-fn to_fn<A,F:Fn<A>>(f: F) -> F { f }
+fn to_fn<A:std::marker::Tuple,F:Fn<A>>(f: F) -> F { f }
 
 fn test(_x: Box<usize>) {}
 
diff --git a/src/test/ui/never_type/exhaustive_patterns.rs b/src/test/ui/never_type/exhaustive_patterns.rs
new file mode 100644
index 000000000000..2e23fa182809
--- /dev/null
+++ b/src/test/ui/never_type/exhaustive_patterns.rs
@@ -0,0 +1,21 @@
+// check-fail
+// known-bug: #104034
+
+#![feature(exhaustive_patterns, never_type)]
+
+mod inner {
+    pub struct Wrapper<T>(T);
+}
+
+enum Either<A, B> {
+    A(A),
+    B(inner::Wrapper<B>),
+}
+
+fn foo() -> Either<(), !> {
+    Either::A(())
+}
+
+fn main() {
+    let Either::A(()) = foo();
+}
diff --git a/src/test/ui/never_type/exhaustive_patterns.stderr b/src/test/ui/never_type/exhaustive_patterns.stderr
new file mode 100644
index 000000000000..e41baf862180
--- /dev/null
+++ b/src/test/ui/never_type/exhaustive_patterns.stderr
@@ -0,0 +1,25 @@
+error[E0005]: refutable pattern in local binding: `Either::B(_)` not covered
+  --> $DIR/exhaustive_patterns.rs:20:9
+   |
+LL |     let Either::A(()) = foo();
+   |         ^^^^^^^^^^^^^ pattern `Either::B(_)` not covered
+   |
+   = note: `let` bindings require an "irrefutable pattern", like a `struct` or an `enum` with only one variant
+   = note: for more information, visit https://doc.rust-lang.org/book/ch18-02-refutability.html
+note: `Either<(), !>` defined here
+  --> $DIR/exhaustive_patterns.rs:12:5
+   |
+LL | enum Either<A, B> {
+   |      ------
+LL |     A(A),
+LL |     B(inner::Wrapper<B>),
+   |     ^ not covered
+   = note: the matched value is of type `Either<(), !>`
+help: you might want to use `if let` to ignore the variant that isn't matched
+   |
+LL |     if let Either::A(()) = foo() { todo!() }
+   |     ++                           ~~~~~~~~~~~
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0005`.
diff --git a/src/test/ui/nll/borrowed-temporary-error.stderr b/src/test/ui/nll/borrowed-temporary-error.stderr
index 2c6bd92641f6..89781d96fab2 100644
--- a/src/test/ui/nll/borrowed-temporary-error.stderr
+++ b/src/test/ui/nll/borrowed-temporary-error.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/borrowed-temporary-error.rs:8:10
    |
 LL |         &(v,)
-   |          ^^^^ creates a temporary which is freed while still in use
+   |          ^^^^ creates a temporary value which is freed while still in use
 LL |
 LL |     });
    |       - temporary value is freed at the end of this statement
diff --git a/src/test/ui/nll/closure-requirements/escape-argument-callee.stderr b/src/test/ui/nll/closure-requirements/escape-argument-callee.stderr
index d2d26b23d646..363ddfaffe06 100644
--- a/src/test/ui/nll/closure-requirements/escape-argument-callee.stderr
+++ b/src/test/ui/nll/closure-requirements/escape-argument-callee.stderr
@@ -6,7 +6,7 @@ LL |         let mut closure = expect_sig(|p, y| *p = y);
    |
    = note: defining type: test::{closure#0} with closure substs [
                i16,
-               for<'a, 'b, 'c> extern "rust-call" fn((&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrNamed('a) }) mut &ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrNamed('b) }) i32, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 2, kind: BrNamed('c) }) i32)),
+               for<Region(BrAnon(0, None)), Region(BrAnon(1, None)), Region(BrAnon(2, None))> extern "rust-call" fn((&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrAnon(0, None) }) mut &ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrAnon(1, None) }) i32, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 2, kind: BrAnon(2, None) }) i32)),
                (),
            ]
 
diff --git a/src/test/ui/nll/closure-requirements/escape-argument.stderr b/src/test/ui/nll/closure-requirements/escape-argument.stderr
index 6355d3295247..f67c312b9468 100644
--- a/src/test/ui/nll/closure-requirements/escape-argument.stderr
+++ b/src/test/ui/nll/closure-requirements/escape-argument.stderr
@@ -6,7 +6,7 @@ LL |         let mut closure = expect_sig(|p, y| *p = y);
    |
    = note: defining type: test::{closure#0} with closure substs [
                i16,
-               for<'a, 'b> extern "rust-call" fn((&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrNamed('a) }) mut &ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrNamed('b) }) i32, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrNamed('b) }) i32)),
+               for<Region(BrAnon(0, None)), Region(BrAnon(1, None))> extern "rust-call" fn((&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrAnon(0, None) }) mut &ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrAnon(1, None) }) i32, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrAnon(1, None) }) i32)),
                (),
            ]
 
diff --git a/src/test/ui/nll/closure-requirements/propagate-approximated-fail-no-postdom.stderr b/src/test/ui/nll/closure-requirements/propagate-approximated-fail-no-postdom.stderr
index 5f9724ce3db1..7da6ce58bf7f 100644
--- a/src/test/ui/nll/closure-requirements/propagate-approximated-fail-no-postdom.stderr
+++ b/src/test/ui/nll/closure-requirements/propagate-approximated-fail-no-postdom.stderr
@@ -6,7 +6,7 @@ LL |         |_outlives1, _outlives2, _outlives3, x, y| {
    |
    = note: defining type: supply::{closure#0} with closure substs [
                i16,
-               for<'a, 'b> extern "rust-call" fn((std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrNamed('a) }) u32>, std::cell::Cell<&'_#2r &ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrNamed('a) }) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrNamed('b) }) &'_#3r u32>, std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrNamed('a) }) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrNamed('b) }) u32>)),
+               for<Region(BrAnon(0, None)), Region(BrAnon(1, None))> extern "rust-call" fn((std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrAnon(0, None) }) u32>, std::cell::Cell<&'_#2r &ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrAnon(0, None) }) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrAnon(1, None) }) &'_#3r u32>, std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrAnon(0, None) }) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrAnon(1, None) }) u32>)),
                (),
            ]
    = note: late-bound region is '_#4r
diff --git a/src/test/ui/nll/closure-requirements/propagate-approximated-ref.stderr b/src/test/ui/nll/closure-requirements/propagate-approximated-ref.stderr
index ec728ebd5adf..993687605c4a 100644
--- a/src/test/ui/nll/closure-requirements/propagate-approximated-ref.stderr
+++ b/src/test/ui/nll/closure-requirements/propagate-approximated-ref.stderr
@@ -6,7 +6,7 @@ LL |     establish_relationships(&cell_a, &cell_b, |_outlives1, _outlives2, x, y
    |
    = note: defining type: supply::{closure#0} with closure substs [
                i16,
-               for<'a, 'b, 'c, 'd, 'e, 'f> extern "rust-call" fn((&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrNamed('a) }) std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrNamed('b) }) u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 2, kind: BrNamed('c) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 3, kind: BrNamed('d) }) &'_#2r u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 4, kind: BrNamed('e) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrNamed('b) }) u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 5, kind: BrNamed('f) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 3, kind: BrNamed('d) }) u32>)),
+               for<Region(BrAnon(0, None)), Region(BrAnon(1, None)), Region(BrAnon(2, None)), Region(BrAnon(3, None)), Region(BrAnon(4, None)), Region(BrAnon(5, None))> extern "rust-call" fn((&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrAnon(0, None) }) std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrAnon(1, None) }) u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 2, kind: BrAnon(2, None) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 3, kind: BrAnon(3, None) }) &'_#2r u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 4, kind: BrAnon(4, None) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrAnon(1, None) }) u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 5, kind: BrAnon(5, None) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 3, kind: BrAnon(3, None) }) u32>)),
                (),
            ]
    = note: late-bound region is '_#3r
diff --git a/src/test/ui/nll/closure-requirements/propagate-approximated-shorter-to-static-comparing-against-free.stderr b/src/test/ui/nll/closure-requirements/propagate-approximated-shorter-to-static-comparing-against-free.stderr
index da4bc499c7e5..7991abeb7a80 100644
--- a/src/test/ui/nll/closure-requirements/propagate-approximated-shorter-to-static-comparing-against-free.stderr
+++ b/src/test/ui/nll/closure-requirements/propagate-approximated-shorter-to-static-comparing-against-free.stderr
@@ -6,7 +6,7 @@ LL |     foo(cell, |cell_a, cell_x| {
    |
    = note: defining type: case1::{closure#0} with closure substs [
                i32,
-               for<'a> extern "rust-call" fn((std::cell::Cell<&'_#1r u32>, std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrNamed('a) }) u32>)),
+               for<Region(BrAnon(0, None))> extern "rust-call" fn((std::cell::Cell<&'_#1r u32>, std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrAnon(0, None) }) u32>)),
                (),
            ]
 
@@ -36,7 +36,7 @@ LL |     foo(cell, |cell_a, cell_x| {
    |
    = note: defining type: case2::{closure#0} with closure substs [
                i32,
-               for<'a> extern "rust-call" fn((std::cell::Cell<&'_#1r u32>, std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrNamed('a) }) u32>)),
+               for<Region(BrAnon(0, None))> extern "rust-call" fn((std::cell::Cell<&'_#1r u32>, std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrAnon(0, None) }) u32>)),
                (),
            ]
    = note: number of external vids: 2
@@ -53,14 +53,15 @@ LL | fn case2() {
 error[E0597]: `a` does not live long enough
   --> $DIR/propagate-approximated-shorter-to-static-comparing-against-free.rs:30:26
    |
-LL |     let cell = Cell::new(&a);
-   |                ----------^^-
-   |                |         |
-   |                |         borrowed value does not live long enough
-   |                argument requires that `a` is borrowed for `'static`
+LL |       let cell = Cell::new(&a);
+   |                            ^^ borrowed value does not live long enough
 ...
-LL | }
-   | - `a` dropped here while still borrowed
+LL | /     foo(cell, |cell_a, cell_x| {
+LL | |         cell_x.set(cell_a.get()); // forces 'a: 'x, implies 'a = 'static -> borrow error
+LL | |     })
+   | |______- argument requires that `a` is borrowed for `'static`
+LL |   }
+   |   - `a` dropped here while still borrowed
 
 error: aborting due to 2 previous errors
 
diff --git a/src/test/ui/nll/closure-requirements/propagate-approximated-shorter-to-static-no-bound.stderr b/src/test/ui/nll/closure-requirements/propagate-approximated-shorter-to-static-no-bound.stderr
index ce85b20b344e..43dfc3bb9f83 100644
--- a/src/test/ui/nll/closure-requirements/propagate-approximated-shorter-to-static-no-bound.stderr
+++ b/src/test/ui/nll/closure-requirements/propagate-approximated-shorter-to-static-no-bound.stderr
@@ -6,7 +6,7 @@ LL |     establish_relationships(&cell_a, &cell_b, |_outlives, x, y| {
    |
    = note: defining type: supply::{closure#0} with closure substs [
                i16,
-               for<'a, 'b, 'c, 'd, 'e> extern "rust-call" fn((&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrNamed('a) }) std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrNamed('b) }) u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 2, kind: BrNamed('c) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrNamed('b) }) u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 3, kind: BrNamed('d) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 4, kind: BrNamed('e) }) u32>)),
+               for<Region(BrAnon(0, None)), Region(BrAnon(1, None)), Region(BrAnon(2, None)), Region(BrAnon(3, None)), Region(BrAnon(4, None))> extern "rust-call" fn((&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrAnon(0, None) }) std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrAnon(1, None) }) u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 2, kind: BrAnon(2, None) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrAnon(1, None) }) u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 3, kind: BrAnon(3, None) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 4, kind: BrAnon(4, None) }) u32>)),
                (),
            ]
    = note: late-bound region is '_#2r
diff --git a/src/test/ui/nll/closure-requirements/propagate-approximated-shorter-to-static-wrong-bound.stderr b/src/test/ui/nll/closure-requirements/propagate-approximated-shorter-to-static-wrong-bound.stderr
index 20c7967b78bc..96c734226eff 100644
--- a/src/test/ui/nll/closure-requirements/propagate-approximated-shorter-to-static-wrong-bound.stderr
+++ b/src/test/ui/nll/closure-requirements/propagate-approximated-shorter-to-static-wrong-bound.stderr
@@ -6,7 +6,7 @@ LL |     establish_relationships(&cell_a, &cell_b, |_outlives1, _outlives2, x, y
    |
    = note: defining type: supply::{closure#0} with closure substs [
                i16,
-               for<'a, 'b, 'c, 'd, 'e, 'f> extern "rust-call" fn((&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrNamed('a) }) std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrNamed('b) }) u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 2, kind: BrNamed('c) }) std::cell::Cell<&'_#2r &ReLateBound(DebruijnIndex(0), BoundRegion { var: 3, kind: BrNamed('d) }) u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 4, kind: BrNamed('e) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrNamed('b) }) u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 5, kind: BrNamed('f) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 3, kind: BrNamed('d) }) u32>)),
+               for<Region(BrAnon(0, None)), Region(BrAnon(1, None)), Region(BrAnon(2, None)), Region(BrAnon(3, None)), Region(BrAnon(4, None)), Region(BrAnon(5, None))> extern "rust-call" fn((&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrAnon(0, None) }) std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrAnon(1, None) }) u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 2, kind: BrAnon(2, None) }) std::cell::Cell<&'_#2r &ReLateBound(DebruijnIndex(0), BoundRegion { var: 3, kind: BrAnon(3, None) }) u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 4, kind: BrAnon(4, None) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrAnon(1, None) }) u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 5, kind: BrAnon(5, None) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 3, kind: BrAnon(3, None) }) u32>)),
                (),
            ]
    = note: late-bound region is '_#3r
diff --git a/src/test/ui/nll/closure-requirements/propagate-approximated-val.stderr b/src/test/ui/nll/closure-requirements/propagate-approximated-val.stderr
index f7db5ab1f27a..03dbd686e497 100644
--- a/src/test/ui/nll/closure-requirements/propagate-approximated-val.stderr
+++ b/src/test/ui/nll/closure-requirements/propagate-approximated-val.stderr
@@ -6,7 +6,7 @@ LL |     establish_relationships(cell_a, cell_b, |outlives1, outlives2, x, y| {
    |
    = note: defining type: test::{closure#0} with closure substs [
                i16,
-               for<'a, 'b> extern "rust-call" fn((std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrNamed('a) }) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrNamed('b) }) &'_#2r u32>, std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrNamed('a) }) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrNamed('b) }) u32>)),
+               for<Region(BrAnon(0, None)), Region(BrAnon(1, None))> extern "rust-call" fn((std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrAnon(0, None) }) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrAnon(1, None) }) &'_#2r u32>, std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrAnon(0, None) }) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrAnon(1, None) }) u32>)),
                (),
            ]
    = note: late-bound region is '_#3r
diff --git a/src/test/ui/nll/closure-requirements/propagate-despite-same-free-region.stderr b/src/test/ui/nll/closure-requirements/propagate-despite-same-free-region.stderr
index 3488edc75e10..d716d3de2a11 100644
--- a/src/test/ui/nll/closure-requirements/propagate-despite-same-free-region.stderr
+++ b/src/test/ui/nll/closure-requirements/propagate-despite-same-free-region.stderr
@@ -6,7 +6,7 @@ LL |         |_outlives1, _outlives2, x, y| {
    |
    = note: defining type: supply::{closure#0} with closure substs [
                i16,
-               for<'a, 'b> extern "rust-call" fn((std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrNamed('a) }) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrNamed('b) }) &'_#2r u32>, std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrNamed('a) }) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrNamed('b) }) u32>)),
+               for<Region(BrAnon(0, None)), Region(BrAnon(1, None))> extern "rust-call" fn((std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrAnon(0, None) }) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrAnon(1, None) }) &'_#2r u32>, std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrAnon(0, None) }) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrAnon(1, None) }) u32>)),
                (),
            ]
    = note: late-bound region is '_#3r
diff --git a/src/test/ui/nll/closure-requirements/propagate-fail-to-approximate-longer-no-bounds.stderr b/src/test/ui/nll/closure-requirements/propagate-fail-to-approximate-longer-no-bounds.stderr
index 0dc2d0de98fe..b924873fca6f 100644
--- a/src/test/ui/nll/closure-requirements/propagate-fail-to-approximate-longer-no-bounds.stderr
+++ b/src/test/ui/nll/closure-requirements/propagate-fail-to-approximate-longer-no-bounds.stderr
@@ -6,7 +6,7 @@ LL |     establish_relationships(&cell_a, &cell_b, |_outlives, x, y| {
    |
    = note: defining type: supply::{closure#0} with closure substs [
                i16,
-               for<'a, 'b, 'c, 'd, 'e> extern "rust-call" fn((&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrNamed('a) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrNamed('b) }) &'_#1r u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 2, kind: BrNamed('c) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 3, kind: BrNamed('d) }) u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 4, kind: BrNamed('e) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrNamed('b) }) u32>)),
+               for<Region(BrAnon(0, None)), Region(BrAnon(1, None)), Region(BrAnon(2, None)), Region(BrAnon(3, None)), Region(BrAnon(4, None))> extern "rust-call" fn((&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrAnon(0, None) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrAnon(1, None) }) &'_#1r u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 2, kind: BrAnon(2, None) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 3, kind: BrAnon(3, None) }) u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 4, kind: BrAnon(4, None) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrAnon(1, None) }) u32>)),
                (),
            ]
    = note: late-bound region is '_#2r
diff --git a/src/test/ui/nll/closure-requirements/propagate-fail-to-approximate-longer-wrong-bounds.stderr b/src/test/ui/nll/closure-requirements/propagate-fail-to-approximate-longer-wrong-bounds.stderr
index 4c9e026ea522..9b25efd0b66b 100644
--- a/src/test/ui/nll/closure-requirements/propagate-fail-to-approximate-longer-wrong-bounds.stderr
+++ b/src/test/ui/nll/closure-requirements/propagate-fail-to-approximate-longer-wrong-bounds.stderr
@@ -6,7 +6,7 @@ LL |     establish_relationships(&cell_a, &cell_b, |_outlives1, _outlives2, x, y
    |
    = note: defining type: supply::{closure#0} with closure substs [
                i16,
-               for<'a, 'b, 'c, 'd, 'e, 'f> extern "rust-call" fn((&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrNamed('a) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrNamed('b) }) &'_#1r u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 2, kind: BrNamed('c) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 3, kind: BrNamed('d) }) &'_#2r u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 4, kind: BrNamed('e) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrNamed('b) }) u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 5, kind: BrNamed('f) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 3, kind: BrNamed('d) }) u32>)),
+               for<Region(BrAnon(0, None)), Region(BrAnon(1, None)), Region(BrAnon(2, None)), Region(BrAnon(3, None)), Region(BrAnon(4, None)), Region(BrAnon(5, None))> extern "rust-call" fn((&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrAnon(0, None) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrAnon(1, None) }) &'_#1r u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 2, kind: BrAnon(2, None) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 3, kind: BrAnon(3, None) }) &'_#2r u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 4, kind: BrAnon(4, None) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrAnon(1, None) }) u32>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 5, kind: BrAnon(5, None) }) std::cell::Cell<&ReLateBound(DebruijnIndex(0), BoundRegion { var: 3, kind: BrAnon(3, None) }) u32>)),
                (),
            ]
    = note: late-bound region is '_#3r
diff --git a/src/test/ui/nll/closure-requirements/propagate-from-trait-match.rs b/src/test/ui/nll/closure-requirements/propagate-from-trait-match.rs
index 3bdb54339485..cda781d8e263 100644
--- a/src/test/ui/nll/closure-requirements/propagate-from-trait-match.rs
+++ b/src/test/ui/nll/closure-requirements/propagate-from-trait-match.rs
@@ -30,8 +30,6 @@ where
     T: Trait<'a>,
 {
     establish_relationships(value, |value| {
-        //~^ ERROR the parameter type `T` may not live long enough
-
         // This function call requires that
         //
         // (a) T: Trait<'a>
@@ -43,6 +41,7 @@ where
         // The latter does not hold.
 
         require(value);
+        //~^ ERROR the parameter type `T` may not live long enough
     });
 }
 
diff --git a/src/test/ui/nll/closure-requirements/propagate-from-trait-match.stderr b/src/test/ui/nll/closure-requirements/propagate-from-trait-match.stderr
index 750b08bbe855..038a5e11f88c 100644
--- a/src/test/ui/nll/closure-requirements/propagate-from-trait-match.stderr
+++ b/src/test/ui/nll/closure-requirements/propagate-from-trait-match.stderr
@@ -23,17 +23,10 @@ LL | |     T: Trait<'a>,
    = note: defining type: supply::<'_#1r, T>
 
 error[E0309]: the parameter type `T` may not live long enough
-  --> $DIR/propagate-from-trait-match.rs:32:36
+  --> $DIR/propagate-from-trait-match.rs:43:9
    |
-LL |       establish_relationships(value, |value| {
-   |  ____________________________________^
-LL | |
-LL | |
-LL | |         // This function call requires that
-...  |
-LL | |         require(value);
-LL | |     });
-   | |_____^ ...so that the type `T` will meet its required lifetime bounds
+LL |         require(value);
+   |         ^^^^^^^^^^^^^^ ...so that the type `T` will meet its required lifetime bounds
    |
 help: consider adding an explicit lifetime bound...
    |
diff --git a/src/test/ui/nll/closure-requirements/return-wrong-bound-region.stderr b/src/test/ui/nll/closure-requirements/return-wrong-bound-region.stderr
index 68429142edec..6db72b886325 100644
--- a/src/test/ui/nll/closure-requirements/return-wrong-bound-region.stderr
+++ b/src/test/ui/nll/closure-requirements/return-wrong-bound-region.stderr
@@ -6,7 +6,7 @@ LL |     expect_sig(|a, b| b); // ought to return `a`
    |
    = note: defining type: test::{closure#0} with closure substs [
                i16,
-               for<'a, 'b> extern "rust-call" fn((&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrNamed('a) }) i32, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrNamed('b) }) i32)) -> &ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrNamed('a) }) i32,
+               for<Region(BrAnon(0, None)), Region(BrAnon(1, None))> extern "rust-call" fn((&ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrAnon(0, None) }) i32, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrAnon(1, None) }) i32)) -> &ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrAnon(0, None) }) i32,
                (),
            ]
 
diff --git a/src/test/ui/nll/issue-48623-generator.stderr b/src/test/ui/nll/issue-48623-generator.stderr
index 1b35165db45d..bfdfca210040 100644
--- a/src/test/ui/nll/issue-48623-generator.stderr
+++ b/src/test/ui/nll/issue-48623-generator.stderr
@@ -2,7 +2,7 @@ warning: unused generator that must be used
   --> $DIR/issue-48623-generator.rs:15:5
    |
 LL |     move || { d; yield; &mut *r };
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: generators are lazy and do nothing unless resumed
    = note: `#[warn(unused_must_use)]` on by default
diff --git a/src/test/ui/issues/issue-54943.rs b/src/test/ui/nll/issue-54943.rs
similarity index 100%
rename from src/test/ui/issues/issue-54943.rs
rename to src/test/ui/nll/issue-54943.rs
diff --git a/src/test/ui/issues/issue-54943.stderr b/src/test/ui/nll/issue-54943.stderr
similarity index 100%
rename from src/test/ui/issues/issue-54943.stderr
rename to src/test/ui/nll/issue-54943.stderr
diff --git a/src/test/ui/nll/issue-57265-return-type-wf-check.stderr b/src/test/ui/nll/issue-57265-return-type-wf-check.stderr
index 20add62b91dd..bb45575fa64c 100644
--- a/src/test/ui/nll/issue-57265-return-type-wf-check.stderr
+++ b/src/test/ui/nll/issue-57265-return-type-wf-check.stderr
@@ -4,7 +4,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     let (_, z) = foo(&"hello".to_string());
    |                  -----^^^^^^^^^^^^^^^^^^^-- temporary value is freed at the end of this statement
    |                  |    |
-   |                  |    creates a temporary which is freed while still in use
+   |                  |    creates a temporary value which is freed while still in use
    |                  argument requires that borrow lasts for `'static`
 
 error: aborting due to previous error
diff --git a/src/test/ui/nll/issue-98589-closures-relate-named-regions.stderr b/src/test/ui/nll/issue-98589-closures-relate-named-regions.stderr
index 6def5602e70b..d8b26f0b0171 100644
--- a/src/test/ui/nll/issue-98589-closures-relate-named-regions.stderr
+++ b/src/test/ui/nll/issue-98589-closures-relate-named-regions.stderr
@@ -35,10 +35,10 @@ LL |     || { None::<&'a &'b ()>; };
    = help: consider adding the following bound: `'b: 'a`
 
 error[E0309]: the parameter type `T` may not live long enough
-  --> $DIR/issue-98589-closures-relate-named-regions.rs:26:5
+  --> $DIR/issue-98589-closures-relate-named-regions.rs:26:10
    |
 LL |     || { None::<&'a T>; };
-   |     ^^^^^^^^^^^^^^^^^^^^^ ...so that the type `T` will meet its required lifetime bounds
+   |          ^^^^^^^^^^^^^ ...so that the type `T` will meet its required lifetime bounds
    |
 help: consider adding an explicit lifetime bound...
    |
@@ -46,10 +46,10 @@ LL | fn test_early_type<'a: 'a, T: 'a>() {
    |                             ++++
 
 error[E0309]: the parameter type `T` may not live long enough
-  --> $DIR/issue-98589-closures-relate-named-regions.rs:32:5
+  --> $DIR/issue-98589-closures-relate-named-regions.rs:32:10
    |
 LL |     || { None::<&'a T>; };
-   |     ^^^^^^^^^^^^^^^^^^^^^ ...so that the type `T` will meet its required lifetime bounds
+   |          ^^^^^^^^^^^^^ ...so that the type `T` will meet its required lifetime bounds
    |
 help: consider adding an explicit lifetime bound...
    |
diff --git a/src/test/ui/nll/issue-98693.rs b/src/test/ui/nll/issue-98693.rs
index 18e6ec630464..7a325e2e998f 100644
--- a/src/test/ui/nll/issue-98693.rs
+++ b/src/test/ui/nll/issue-98693.rs
@@ -13,8 +13,8 @@ where
 
 fn test<T>() {
     || {
-        //~^ ERROR the parameter type `T` may not live long enough
         assert_static::<T>();
+        //~^ ERROR the parameter type `T` may not live long enough
     };
 }
 
diff --git a/src/test/ui/nll/issue-98693.stderr b/src/test/ui/nll/issue-98693.stderr
index 31689620c641..15ca38aa25dc 100644
--- a/src/test/ui/nll/issue-98693.stderr
+++ b/src/test/ui/nll/issue-98693.stderr
@@ -1,11 +1,8 @@
 error[E0310]: the parameter type `T` may not live long enough
-  --> $DIR/issue-98693.rs:15:5
+  --> $DIR/issue-98693.rs:16:9
    |
-LL | /     || {
-LL | |
-LL | |         assert_static::<T>();
-LL | |     };
-   | |_____^ ...so that the type `T` will meet its required lifetime bounds
+LL |         assert_static::<T>();
+   |         ^^^^^^^^^^^^^^^^^^^^ ...so that the type `T` will meet its required lifetime bounds
    |
 help: consider adding an explicit lifetime bound...
    |
diff --git a/src/test/ui/nll/ty-outlives/impl-trait-captures.stderr b/src/test/ui/nll/ty-outlives/impl-trait-captures.stderr
index 6a8a1ad1caad..737cb35841cf 100644
--- a/src/test/ui/nll/ty-outlives/impl-trait-captures.stderr
+++ b/src/test/ui/nll/ty-outlives/impl-trait-captures.stderr
@@ -6,7 +6,7 @@ LL | fn foo<'a, T>(x: &T) -> impl Foo<'a> {
 LL |     x
    |     ^
    |
-help: to declare that the `impl Trait` captures `ReFree(DefId(0:8 ~ impl_trait_captures[1afc]::foo), BrNamed(DefId(0:12 ~ impl_trait_captures[1afc]::foo::'_), '_))`, you can add an explicit `ReFree(DefId(0:8 ~ impl_trait_captures[1afc]::foo), BrNamed(DefId(0:12 ~ impl_trait_captures[1afc]::foo::'_), '_))` lifetime bound
+help: to declare that `Opaque(DefId(0:13 ~ impl_trait_captures[1afc]::foo::{opaque#0}), [ReEarlyBound(0, 'a), T, ReEarlyBound(2, 'a)])` captures `ReFree(DefId(0:8 ~ impl_trait_captures[1afc]::foo), BrNamed(DefId(0:12 ~ impl_trait_captures[1afc]::foo::'_), '_))`, you can add an explicit `ReFree(DefId(0:8 ~ impl_trait_captures[1afc]::foo), BrNamed(DefId(0:12 ~ impl_trait_captures[1afc]::foo::'_), '_))` lifetime bound
    |
 LL | fn foo<'a, T>(x: &T) -> impl Foo<'a> + ReFree(DefId(0:8 ~ impl_trait_captures[1afc]::foo), BrNamed(DefId(0:12 ~ impl_trait_captures[1afc]::foo::'_), '_)) {
    |                                      ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
diff --git a/src/test/ui/nll/ty-outlives/projection-implied-bounds.stderr b/src/test/ui/nll/ty-outlives/projection-implied-bounds.stderr
index 3b9b2956c518..d949e29b2b81 100644
--- a/src/test/ui/nll/ty-outlives/projection-implied-bounds.stderr
+++ b/src/test/ui/nll/ty-outlives/projection-implied-bounds.stderr
@@ -1,8 +1,8 @@
 error[E0310]: the parameter type `T` may not live long enough
-  --> $DIR/projection-implied-bounds.rs:30:18
+  --> $DIR/projection-implied-bounds.rs:30:36
    |
 LL |     twice(value, |value_ref, item| invoke2(value_ref, item));
-   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ...so that the type `T` will meet its required lifetime bounds
+   |                                    ^^^^^^^^^^^^^^^^^^^^^^^^ ...so that the type `T` will meet its required lifetime bounds
    |
 help: consider adding an explicit lifetime bound...
    |
diff --git a/src/test/ui/nll/ty-outlives/projection-no-regions-closure.stderr b/src/test/ui/nll/ty-outlives/projection-no-regions-closure.stderr
index ee1f7b64bb23..4933b9348683 100644
--- a/src/test/ui/nll/ty-outlives/projection-no-regions-closure.stderr
+++ b/src/test/ui/nll/ty-outlives/projection-no-regions-closure.stderr
@@ -23,10 +23,10 @@ LL | |     T: Iterator,
    = note: defining type: no_region::<'_#1r, T>
 
 error[E0309]: the associated type `<T as Iterator>::Item` may not live long enough
-  --> $DIR/projection-no-regions-closure.rs:25:23
+  --> $DIR/projection-no-regions-closure.rs:25:31
    |
 LL |     with_signature(x, |mut y| Box::new(y.next()))
-   |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |                               ^^^^^^^^^^^^^^^^^^
    |
    = help: consider adding an explicit lifetime bound `<T as Iterator>::Item: 'a`...
    = note: ...so that the type `<T as Iterator>::Item` will meet its required lifetime bounds
@@ -80,10 +80,10 @@ LL | |     T: 'b + Iterator,
    = note: defining type: wrong_region::<'_#1r, '_#2r, T>
 
 error[E0309]: the associated type `<T as Iterator>::Item` may not live long enough
-  --> $DIR/projection-no-regions-closure.rs:42:23
+  --> $DIR/projection-no-regions-closure.rs:42:31
    |
 LL |     with_signature(x, |mut y| Box::new(y.next()))
-   |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |                               ^^^^^^^^^^^^^^^^^^
    |
    = help: consider adding an explicit lifetime bound `<T as Iterator>::Item: 'a`...
    = note: ...so that the type `<T as Iterator>::Item` will meet its required lifetime bounds
diff --git a/src/test/ui/nll/ty-outlives/projection-one-region-closure.stderr b/src/test/ui/nll/ty-outlives/projection-one-region-closure.stderr
index 4e57dfad794e..dbda04c42c5c 100644
--- a/src/test/ui/nll/ty-outlives/projection-one-region-closure.stderr
+++ b/src/test/ui/nll/ty-outlives/projection-one-region-closure.stderr
@@ -25,10 +25,10 @@ LL | |     T: Anything<'b>,
    = note: defining type: no_relationships_late::<'_#1r, T>
 
 error[E0309]: the parameter type `T` may not live long enough
-  --> $DIR/projection-one-region-closure.rs:45:29
+  --> $DIR/projection-one-region-closure.rs:45:39
    |
 LL |     with_signature(cell, t, |cell, t| require(cell, t));
-   |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^ ...so that the type `T` will meet its required lifetime bounds
+   |                                       ^^^^^^^^^^^^^^^^ ...so that the type `T` will meet its required lifetime bounds
    |
 help: consider adding an explicit lifetime bound...
    |
@@ -75,10 +75,10 @@ LL | |     'a: 'a,
    = note: defining type: no_relationships_early::<'_#1r, '_#2r, T>
 
 error[E0309]: the parameter type `T` may not live long enough
-  --> $DIR/projection-one-region-closure.rs:56:29
+  --> $DIR/projection-one-region-closure.rs:56:39
    |
 LL |     with_signature(cell, t, |cell, t| require(cell, t));
-   |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^ ...so that the type `T` will meet its required lifetime bounds
+   |                                       ^^^^^^^^^^^^^^^^ ...so that the type `T` will meet its required lifetime bounds
    |
 help: consider adding an explicit lifetime bound...
    |
diff --git a/src/test/ui/nll/ty-outlives/projection-two-region-trait-bound-closure.stderr b/src/test/ui/nll/ty-outlives/projection-two-region-trait-bound-closure.stderr
index 0195a693e5ff..90f04914286c 100644
--- a/src/test/ui/nll/ty-outlives/projection-two-region-trait-bound-closure.stderr
+++ b/src/test/ui/nll/ty-outlives/projection-two-region-trait-bound-closure.stderr
@@ -24,10 +24,10 @@ LL | |     T: Anything<'b, 'c>,
    = note: defining type: no_relationships_late::<'_#1r, '_#2r, T>
 
 error[E0309]: the associated type `<T as Anything<ReEarlyBound(0, 'b), ReEarlyBound(1, 'c)>>::AssocType` may not live long enough
-  --> $DIR/projection-two-region-trait-bound-closure.rs:38:29
+  --> $DIR/projection-two-region-trait-bound-closure.rs:38:39
    |
 LL |     with_signature(cell, t, |cell, t| require(cell, t));
-   |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |                                       ^^^^^^^^^^^^^^^^
    |
    = help: consider adding an explicit lifetime bound `<T as Anything<ReEarlyBound(0, 'b), ReEarlyBound(1, 'c)>>::AssocType: 'a`...
    = note: ...so that the type `<T as Anything<ReEarlyBound(0, 'b), ReEarlyBound(1, 'c)>>::AssocType` will meet its required lifetime bounds
@@ -58,10 +58,10 @@ LL | |     'a: 'a,
    = note: defining type: no_relationships_early::<'_#1r, '_#2r, '_#3r, T>
 
 error[E0309]: the associated type `<T as Anything<ReEarlyBound(1, 'b), ReEarlyBound(2, 'c)>>::AssocType` may not live long enough
-  --> $DIR/projection-two-region-trait-bound-closure.rs:48:29
+  --> $DIR/projection-two-region-trait-bound-closure.rs:48:39
    |
 LL |     with_signature(cell, t, |cell, t| require(cell, t));
-   |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |                                       ^^^^^^^^^^^^^^^^
    |
    = help: consider adding an explicit lifetime bound `<T as Anything<ReEarlyBound(1, 'b), ReEarlyBound(2, 'c)>>::AssocType: 'a`...
    = note: ...so that the type `<T as Anything<ReEarlyBound(1, 'b), ReEarlyBound(2, 'c)>>::AssocType` will meet its required lifetime bounds
@@ -167,7 +167,7 @@ LL | |     T: Anything<'b, 'b>,
    = note: defining type: two_regions::<'_#1r, T>
 
 error: lifetime may not live long enough
-  --> $DIR/projection-two-region-trait-bound-closure.rs:87:29
+  --> $DIR/projection-two-region-trait-bound-closure.rs:87:5
    |
 LL | fn two_regions<'a, 'b, T>(cell: Cell<&'a ()>, t: T)
    |                --  -- lifetime `'b` defined here
@@ -175,9 +175,12 @@ LL | fn two_regions<'a, 'b, T>(cell: Cell<&'a ()>, t: T)
    |                lifetime `'a` defined here
 ...
 LL |     with_signature(cell, t, |cell, t| require(cell, t));
-   |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^ closure body requires that `'b` must outlive `'a`
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ argument requires that `'b` must outlive `'a`
    |
    = help: consider adding the following bound: `'b: 'a`
+   = note: requirement occurs because of the type `Cell<&'_#8r ()>`, which makes the generic argument `&'_#8r ()` invariant
+   = note: the struct `Cell<T>` is invariant over the parameter `T`
+   = help: see <https://doc.rust-lang.org/nomicon/subtyping.html> for more information about variance
 
 note: external requirements
   --> $DIR/projection-two-region-trait-bound-closure.rs:97:29
diff --git a/src/test/ui/nll/ty-outlives/ty-param-closure-approximate-lower-bound.stderr b/src/test/ui/nll/ty-outlives/ty-param-closure-approximate-lower-bound.stderr
index 61c7d2550caa..a442cf12d820 100644
--- a/src/test/ui/nll/ty-outlives/ty-param-closure-approximate-lower-bound.stderr
+++ b/src/test/ui/nll/ty-outlives/ty-param-closure-approximate-lower-bound.stderr
@@ -6,7 +6,7 @@ LL |     twice(cell, value, |a, b| invoke(a, b));
    |
    = note: defining type: generic::<T>::{closure#0} with closure substs [
                i16,
-               for<'a, 'b> extern "rust-call" fn((std::option::Option<std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrNamed('a) }) ()>>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrNamed('b) }) T)),
+               for<Region(BrAnon(0, None)), Region(BrAnon(1, None))> extern "rust-call" fn((std::option::Option<std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrAnon(0, None) }) ()>>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrAnon(1, None) }) T)),
                (),
            ]
    = note: number of external vids: 2
@@ -28,7 +28,7 @@ LL |     twice(cell, value, |a, b| invoke(a, b));
    |
    = note: defining type: generic_fail::<T>::{closure#0} with closure substs [
                i16,
-               for<'a, 'b> extern "rust-call" fn((std::option::Option<std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrNamed('a) }) ()>>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrNamed('b) }) T)),
+               for<Region(BrAnon(0, None)), Region(BrAnon(1, None))> extern "rust-call" fn((std::option::Option<std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrAnon(0, None) }) ()>>, &ReLateBound(DebruijnIndex(0), BoundRegion { var: 1, kind: BrAnon(1, None) }) T)),
                (),
            ]
    = note: late-bound region is '_#2r
@@ -44,10 +44,10 @@ LL | fn generic_fail<'a, T>(cell: Cell<&'a ()>, value: T) {
    = note: defining type: generic_fail::<T>
 
 error[E0309]: the parameter type `T` may not live long enough
-  --> $DIR/ty-param-closure-approximate-lower-bound.rs:29:24
+  --> $DIR/ty-param-closure-approximate-lower-bound.rs:29:31
    |
 LL |     twice(cell, value, |a, b| invoke(a, b));
-   |                        ^^^^^^^^^^^^^^^^^^^ ...so that the type `T` will meet its required lifetime bounds
+   |                               ^^^^^^^^^^^^ ...so that the type `T` will meet its required lifetime bounds
    |
 help: consider adding an explicit lifetime bound...
    |
diff --git a/src/test/ui/nll/ty-outlives/ty-param-closure-outlives-from-return-type.stderr b/src/test/ui/nll/ty-outlives/ty-param-closure-outlives-from-return-type.stderr
index 50d9e3aabe2d..35979c8bf517 100644
--- a/src/test/ui/nll/ty-outlives/ty-param-closure-outlives-from-return-type.stderr
+++ b/src/test/ui/nll/ty-outlives/ty-param-closure-outlives-from-return-type.stderr
@@ -23,10 +23,10 @@ LL | |     T: Debug,
    = note: defining type: no_region::<'_#1r, T>
 
 error[E0309]: the parameter type `T` may not live long enough
-  --> $DIR/ty-param-closure-outlives-from-return-type.rs:26:23
+  --> $DIR/ty-param-closure-outlives-from-return-type.rs:26:27
    |
 LL |     with_signature(x, |y| y)
-   |                       ^^^^^ ...so that the type `T` will meet its required lifetime bounds
+   |                           ^ ...so that the type `T` will meet its required lifetime bounds
    |
 help: consider adding an explicit lifetime bound...
    |
diff --git a/src/test/ui/nll/ty-outlives/ty-param-closure-outlives-from-where-clause.rs b/src/test/ui/nll/ty-outlives/ty-param-closure-outlives-from-where-clause.rs
index d7702def32c5..b80287610504 100644
--- a/src/test/ui/nll/ty-outlives/ty-param-closure-outlives-from-where-clause.rs
+++ b/src/test/ui/nll/ty-outlives/ty-param-closure-outlives-from-where-clause.rs
@@ -25,13 +25,12 @@ where
 #[rustc_regions]
 fn no_region<'a, T>(a: Cell<&'a ()>, b: T) {
     with_signature(a, b, |x, y| {
-        //~^ ERROR the parameter type `T` may not live long enough
-        //
         // See `correct_region`, which explains the point of this
         // test.  The only difference is that, in the case of this
         // function, there is no where clause *anywhere*, and hence we
         // get an error (but reported by the closure creator).
         require(&x, &y)
+        //~^ ERROR the parameter type `T` may not live long enough
     })
 }
 
@@ -62,9 +61,9 @@ where
     T: 'b,
 {
     with_signature(a, b, |x, y| {
-        //~^ ERROR the parameter type `T` may not live long enough
         // See `correct_region`
         require(&x, &y)
+        //~^ ERROR the parameter type `T` may not live long enough
     })
 }
 
diff --git a/src/test/ui/nll/ty-outlives/ty-param-closure-outlives-from-where-clause.stderr b/src/test/ui/nll/ty-outlives/ty-param-closure-outlives-from-where-clause.stderr
index 14c55e32a3eb..4c97db58c6c3 100644
--- a/src/test/ui/nll/ty-outlives/ty-param-closure-outlives-from-where-clause.stderr
+++ b/src/test/ui/nll/ty-outlives/ty-param-closure-outlives-from-where-clause.stderr
@@ -22,17 +22,10 @@ LL | fn no_region<'a, T>(a: Cell<&'a ()>, b: T) {
    = note: defining type: no_region::<T>
 
 error[E0309]: the parameter type `T` may not live long enough
-  --> $DIR/ty-param-closure-outlives-from-where-clause.rs:27:26
+  --> $DIR/ty-param-closure-outlives-from-where-clause.rs:32:9
    |
-LL |       with_signature(a, b, |x, y| {
-   |  __________________________^
-LL | |
-LL | |         //
-LL | |         // See `correct_region`, which explains the point of this
-...  |
-LL | |         require(&x, &y)
-LL | |     })
-   | |_____^ ...so that the type `T` will meet its required lifetime bounds
+LL |         require(&x, &y)
+   |         ^^^^^^^^^^^^^^^ ...so that the type `T` will meet its required lifetime bounds
    |
 help: consider adding an explicit lifetime bound...
    |
@@ -40,7 +33,7 @@ LL | fn no_region<'a, T: 'a>(a: Cell<&'a ()>, b: T) {
    |                   ++++
 
 note: external requirements
-  --> $DIR/ty-param-closure-outlives-from-where-clause.rs:43:26
+  --> $DIR/ty-param-closure-outlives-from-where-clause.rs:42:26
    |
 LL |     with_signature(a, b, |x, y| {
    |                          ^^^^^^
@@ -54,7 +47,7 @@ LL |     with_signature(a, b, |x, y| {
    = note: where T: '_#2r
 
 note: no external requirements
-  --> $DIR/ty-param-closure-outlives-from-where-clause.rs:39:1
+  --> $DIR/ty-param-closure-outlives-from-where-clause.rs:38:1
    |
 LL | / fn correct_region<'a, T>(a: Cell<&'a ()>, b: T)
 LL | | where
@@ -64,7 +57,7 @@ LL | |     T: 'a,
    = note: defining type: correct_region::<'_#1r, T>
 
 note: external requirements
-  --> $DIR/ty-param-closure-outlives-from-where-clause.rs:64:26
+  --> $DIR/ty-param-closure-outlives-from-where-clause.rs:63:26
    |
 LL |     with_signature(a, b, |x, y| {
    |                          ^^^^^^
@@ -79,7 +72,7 @@ LL |     with_signature(a, b, |x, y| {
    = note: where T: '_#2r
 
 note: no external requirements
-  --> $DIR/ty-param-closure-outlives-from-where-clause.rs:60:1
+  --> $DIR/ty-param-closure-outlives-from-where-clause.rs:59:1
    |
 LL | / fn wrong_region<'a, 'b, T>(a: Cell<&'a ()>, b: T)
 LL | | where
@@ -89,15 +82,10 @@ LL | |     T: 'b,
    = note: defining type: wrong_region::<'_#1r, T>
 
 error[E0309]: the parameter type `T` may not live long enough
-  --> $DIR/ty-param-closure-outlives-from-where-clause.rs:64:26
+  --> $DIR/ty-param-closure-outlives-from-where-clause.rs:65:9
    |
-LL |       with_signature(a, b, |x, y| {
-   |  __________________________^
-LL | |
-LL | |         // See `correct_region`
-LL | |         require(&x, &y)
-LL | |     })
-   | |_____^ ...so that the type `T` will meet its required lifetime bounds
+LL |         require(&x, &y)
+   |         ^^^^^^^^^^^^^^^ ...so that the type `T` will meet its required lifetime bounds
    |
 help: consider adding an explicit lifetime bound...
    |
@@ -105,7 +93,7 @@ LL |     T: 'b + 'a,
    |           ++++
 
 note: external requirements
-  --> $DIR/ty-param-closure-outlives-from-where-clause.rs:77:26
+  --> $DIR/ty-param-closure-outlives-from-where-clause.rs:76:26
    |
 LL |     with_signature(a, b, |x, y| {
    |                          ^^^^^^
@@ -119,7 +107,7 @@ LL |     with_signature(a, b, |x, y| {
    = note: where T: '_#3r
 
 note: no external requirements
-  --> $DIR/ty-param-closure-outlives-from-where-clause.rs:72:1
+  --> $DIR/ty-param-closure-outlives-from-where-clause.rs:71:1
    |
 LL | / fn outlives_region<'a, 'b, T>(a: Cell<&'a ()>, b: T)
 LL | | where
diff --git a/src/test/ui/nll/user-annotations/adt-nullary-enums.stderr b/src/test/ui/nll/user-annotations/adt-nullary-enums.stderr
index bb7034122288..3326fa521fc9 100644
--- a/src/test/ui/nll/user-annotations/adt-nullary-enums.stderr
+++ b/src/test/ui/nll/user-annotations/adt-nullary-enums.stderr
@@ -1,14 +1,14 @@
 error[E0597]: `c` does not live long enough
   --> $DIR/adt-nullary-enums.rs:33:41
    |
-LL |         SomeEnum::SomeVariant(Cell::new(&c)),
-   |                               ----------^^-
-   |                               |         |
-   |                               |         borrowed value does not live long enough
-   |                               argument requires that `c` is borrowed for `'static`
-...
-LL | }
-   | - `c` dropped here while still borrowed
+LL | /     combine(
+LL | |         SomeEnum::SomeVariant(Cell::new(&c)),
+   | |                                         ^^ borrowed value does not live long enough
+LL | |         SomeEnum::SomeOtherVariant::<Cell<&'static u32>>,
+LL | |     );
+   | |_____- argument requires that `c` is borrowed for `'static`
+LL |   }
+   |   - `c` dropped here while still borrowed
 
 error[E0597]: `c` does not live long enough
   --> $DIR/adt-nullary-enums.rs:41:41
diff --git a/src/test/ui/nll/user-annotations/ascribed-type-wf.rs b/src/test/ui/nll/user-annotations/ascribed-type-wf.rs
new file mode 100644
index 000000000000..14460dea5b52
--- /dev/null
+++ b/src/test/ui/nll/user-annotations/ascribed-type-wf.rs
@@ -0,0 +1,16 @@
+// check-pass
+// known-bug: #101350
+
+trait Trait {
+    type Ty;
+}
+
+impl Trait for &'static () {
+    type Ty = ();
+}
+
+fn extend<'a>() {
+    None::<<&'a () as Trait>::Ty>;
+}
+
+fn main() {}
diff --git a/src/test/ui/nll/user-annotations/patterns.stderr b/src/test/ui/nll/user-annotations/patterns.stderr
index 60d6e6db3632..de6f8f80fe25 100644
--- a/src/test/ui/nll/user-annotations/patterns.stderr
+++ b/src/test/ui/nll/user-annotations/patterns.stderr
@@ -76,7 +76,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     let _: Vec<&'static String> = vec![&String::new()];
    |            --------------------         ^^^^^^^^^^^^^ - temporary value is freed at the end of this statement
    |            |                            |
-   |            |                            creates a temporary which is freed while still in use
+   |            |                            creates a temporary value which is freed while still in use
    |            type annotation requires that borrow lasts for `'static`
 
 error[E0716]: temporary value dropped while borrowed
@@ -85,7 +85,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     let (_, a): (Vec<&'static String>, _) = (vec![&String::new()], 44);
    |                 -------------------------          ^^^^^^^^^^^^^      - temporary value is freed at the end of this statement
    |                 |                                  |
-   |                 |                                  creates a temporary which is freed while still in use
+   |                 |                                  creates a temporary value which is freed while still in use
    |                 type annotation requires that borrow lasts for `'static`
 
 error[E0716]: temporary value dropped while borrowed
@@ -94,7 +94,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     let (_a, b): (Vec<&'static String>, _) = (vec![&String::new()], 44);
    |                  -------------------------          ^^^^^^^^^^^^^      - temporary value is freed at the end of this statement
    |                  |                                  |
-   |                  |                                  creates a temporary which is freed while still in use
+   |                  |                                  creates a temporary value which is freed while still in use
    |                  type annotation requires that borrow lasts for `'static`
 
 error[E0597]: `x` does not live long enough
diff --git a/src/test/ui/on-unimplemented/issue-104140.rs b/src/test/ui/on-unimplemented/issue-104140.rs
new file mode 100644
index 000000000000..ade3f727004a
--- /dev/null
+++ b/src/test/ui/on-unimplemented/issue-104140.rs
@@ -0,0 +1,8 @@
+#![feature(rustc_attrs)]
+
+trait Foo {}
+
+#[rustc_on_unimplemented] //~ ERROR malformed `rustc_on_unimplemented` attribute input
+impl Foo for u32 {}
+
+fn main() {}
diff --git a/src/test/ui/on-unimplemented/issue-104140.stderr b/src/test/ui/on-unimplemented/issue-104140.stderr
new file mode 100644
index 000000000000..ddb1f50f0bb4
--- /dev/null
+++ b/src/test/ui/on-unimplemented/issue-104140.stderr
@@ -0,0 +1,15 @@
+error: malformed `rustc_on_unimplemented` attribute input
+  --> $DIR/issue-104140.rs:5:1
+   |
+LL | #[rustc_on_unimplemented]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: the following are the possible correct uses
+   |
+LL | #[rustc_on_unimplemented = "message"]
+   | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+LL | #[rustc_on_unimplemented(/*opt*/ message = "...", /*opt*/ label = "...", /*opt*/ note = "...")]
+   | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+error: aborting due to previous error
+
diff --git a/src/test/ui/or-patterns/or-patterns-syntactic-fail-2018.stderr b/src/test/ui/or-patterns/or-patterns-syntactic-fail-2018.stderr
index 001c68a97747..acc2099bbc6a 100644
--- a/src/test/ui/or-patterns/or-patterns-syntactic-fail-2018.stderr
+++ b/src/test/ui/or-patterns/or-patterns-syntactic-fail-2018.stderr
@@ -6,6 +6,12 @@ LL | macro_rules! accept_pat {
 ...
 LL | accept_pat!(p | q);
    |               ^ no rules expected this token in macro call
+   |
+note: while trying to match meta-variable `$p:pat`
+  --> $DIR/or-patterns-syntactic-fail-2018.rs:9:6
+   |
+LL |     ($p:pat) => {};
+   |      ^^^^^^
 
 error: no rules expected the token `|`
   --> $DIR/or-patterns-syntactic-fail-2018.rs:13:13
@@ -15,6 +21,12 @@ LL | macro_rules! accept_pat {
 ...
 LL | accept_pat!(|p| q);
    |             ^ no rules expected this token in macro call
+   |
+note: while trying to match meta-variable `$p:pat`
+  --> $DIR/or-patterns-syntactic-fail-2018.rs:9:6
+   |
+LL |     ($p:pat) => {};
+   |      ^^^^^^
 
 error: aborting due to 2 previous errors
 
diff --git a/src/test/ui/overloaded/overloaded-calls-nontuple.rs b/src/test/ui/overloaded/overloaded-calls-nontuple.rs
index 07d44ff82b13..32a3b93e0a1e 100644
--- a/src/test/ui/overloaded/overloaded-calls-nontuple.rs
+++ b/src/test/ui/overloaded/overloaded-calls-nontuple.rs
@@ -8,22 +8,23 @@ struct S {
 }
 
 impl FnMut<isize> for S {
+    //~^ ERROR type parameter to bare `FnMut` trait must be a tuple
     extern "rust-call" fn call_mut(&mut self, z: isize) -> isize {
+        //~^ ERROR functions with the "rust-call" ABI must take a single non-self tuple argument
         self.x + self.y + z
     }
-    //~^^^ ERROR functions with the "rust-call" ABI must take a single non-self argument
 }
 
 impl FnOnce<isize> for S {
+    //~^ ERROR type parameter to bare `FnOnce` trait must be a tuple
     type Output = isize;
-    extern "rust-call" fn call_once(mut self, z: isize) -> isize { self.call_mut(z) }
-    //~^ ERROR functions with the "rust-call" ABI must take a single non-self argument
+    extern "rust-call" fn call_once(mut self, z: isize) -> isize {
+        //~^ ERROR functions with the "rust-call" ABI must take a single non-self tuple argument
+        self.call_mut(z)
+    }
 }
 
 fn main() {
-    let mut s = S {
-        x: 1,
-        y: 2,
-    };
-    drop(s(3))  //~ ERROR cannot use call notation
+    let mut s = S { x: 1, y: 2 };
+    drop(s(3))
 }
diff --git a/src/test/ui/overloaded/overloaded-calls-nontuple.stderr b/src/test/ui/overloaded/overloaded-calls-nontuple.stderr
index 8f299bc9434f..794535aeb110 100644
--- a/src/test/ui/overloaded/overloaded-calls-nontuple.stderr
+++ b/src/test/ui/overloaded/overloaded-calls-nontuple.stderr
@@ -1,21 +1,40 @@
-error: functions with the "rust-call" ABI must take a single non-self argument that is a tuple
-  --> $DIR/overloaded-calls-nontuple.rs:11:5
+error[E0059]: type parameter to bare `FnMut` trait must be a tuple
+  --> $DIR/overloaded-calls-nontuple.rs:10:6
+   |
+LL | impl FnMut<isize> for S {
+   |      ^^^^^^^^^^^^ the trait `Tuple` is not implemented for `isize`
+   |
+note: required by a bound in `FnMut`
+  --> $SRC_DIR/core/src/ops/function.rs:LL:COL
+   |
+LL | pub trait FnMut<Args: Tuple>: FnOnce<Args> {
+   |                       ^^^^^ required by this bound in `FnMut`
+
+error[E0059]: type parameter to bare `FnOnce` trait must be a tuple
+  --> $DIR/overloaded-calls-nontuple.rs:18:6
+   |
+LL | impl FnOnce<isize> for S {
+   |      ^^^^^^^^^^^^^ the trait `Tuple` is not implemented for `isize`
+   |
+note: required by a bound in `FnOnce`
+  --> $SRC_DIR/core/src/ops/function.rs:LL:COL
+   |
+LL | pub trait FnOnce<Args: Tuple> {
+   |                        ^^^^^ required by this bound in `FnOnce`
+
+error[E0277]: functions with the "rust-call" ABI must take a single non-self tuple argument
+  --> $DIR/overloaded-calls-nontuple.rs:12:5
    |
 LL |     extern "rust-call" fn call_mut(&mut self, z: isize) -> isize {
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Tuple` is not implemented for `isize`
 
-error: functions with the "rust-call" ABI must take a single non-self argument that is a tuple
-  --> $DIR/overloaded-calls-nontuple.rs:19:5
+error[E0277]: functions with the "rust-call" ABI must take a single non-self tuple argument
+  --> $DIR/overloaded-calls-nontuple.rs:21:5
    |
-LL |     extern "rust-call" fn call_once(mut self, z: isize) -> isize { self.call_mut(z) }
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+LL |     extern "rust-call" fn call_once(mut self, z: isize) -> isize {
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Tuple` is not implemented for `isize`
 
-error[E0059]: cannot use call notation; the first type parameter for the function trait is neither a tuple nor unit
-  --> $DIR/overloaded-calls-nontuple.rs:28:10
-   |
-LL |     drop(s(3))
-   |          ^^^^
+error: aborting due to 4 previous errors
 
-error: aborting due to 3 previous errors
-
-For more information about this error, try `rustc --explain E0059`.
+Some errors have detailed explanations: E0059, E0277.
+For more information about an error, try `rustc --explain E0059`.
diff --git a/src/test/ui/parser/byte-literals.rs b/src/test/ui/parser/byte-literals.rs
index 05a510b24a7a..896dc1a1a5fb 100644
--- a/src/test/ui/parser/byte-literals.rs
+++ b/src/test/ui/parser/byte-literals.rs
@@ -7,6 +7,6 @@ pub fn main() {
     b'\x0Z';  //~ ERROR invalid character in numeric character escape: `Z`
     b'	';  //~ ERROR byte constant must be escaped
     b''';  //~ ERROR byte constant must be escaped
-    b'é';  //~ ERROR non-ASCII character in byte constant
+    b'é';  //~ ERROR non-ASCII character in byte literal
     b'a  //~ ERROR unterminated byte constant [E0763]
 }
diff --git a/src/test/ui/parser/byte-literals.stderr b/src/test/ui/parser/byte-literals.stderr
index c3d000616300..efa55ae05bd3 100644
--- a/src/test/ui/parser/byte-literals.stderr
+++ b/src/test/ui/parser/byte-literals.stderr
@@ -32,11 +32,11 @@ error: byte constant must be escaped: `'`
 LL |     b''';
    |       ^ help: escape the character: `\'`
 
-error: non-ASCII character in byte constant
+error: non-ASCII character in byte literal
   --> $DIR/byte-literals.rs:10:7
    |
 LL |     b'é';
-   |       ^ byte constant must be ASCII
+   |       ^ must be ASCII
    |
 help: if you meant to use the unicode code point for 'é', use a \xHH escape
    |
diff --git a/src/test/ui/parser/byte-string-literals.rs b/src/test/ui/parser/byte-string-literals.rs
index b1f11024a7bb..30a4f50c4e40 100644
--- a/src/test/ui/parser/byte-string-literals.rs
+++ b/src/test/ui/parser/byte-string-literals.rs
@@ -3,7 +3,7 @@ static FOO: &'static [u8] = b"\f";  //~ ERROR unknown byte escape
 pub fn main() {
     b"\f";  //~ ERROR unknown byte escape
     b"\x0Z";  //~ ERROR invalid character in numeric character escape: `Z`
-    b"é";  //~ ERROR non-ASCII character in byte constant
-    br##"é"##;  //~ ERROR raw byte string must be ASCII
+    b"é";  //~ ERROR non-ASCII character in byte string literal
+    br##"é"##;  //~ ERROR non-ASCII character in raw byte string literal
     b"a  //~ ERROR unterminated double quote byte string
 }
diff --git a/src/test/ui/parser/byte-string-literals.stderr b/src/test/ui/parser/byte-string-literals.stderr
index 3b8b3692e053..5b96cc3d18ab 100644
--- a/src/test/ui/parser/byte-string-literals.stderr
+++ b/src/test/ui/parser/byte-string-literals.stderr
@@ -20,18 +20,18 @@ error: invalid character in numeric character escape: `Z`
 LL |     b"\x0Z";
    |          ^ invalid character in numeric character escape
 
-error: non-ASCII character in byte constant
+error: non-ASCII character in byte string literal
   --> $DIR/byte-string-literals.rs:6:7
    |
 LL |     b"é";
-   |       ^ byte constant must be ASCII
+   |       ^ must be ASCII
    |
 help: if you meant to use the unicode code point for 'é', use a \xHH escape
    |
 LL |     b"\xE9";
    |       ~~~~
 
-error: raw byte string must be ASCII
+error: non-ASCII character in raw byte string literal
   --> $DIR/byte-string-literals.rs:7:10
    |
 LL |     br##"é"##;
diff --git a/src/test/ui/parser/issue-102806.rs b/src/test/ui/parser/issue-102806.rs
new file mode 100644
index 000000000000..ba297bdc9677
--- /dev/null
+++ b/src/test/ui/parser/issue-102806.rs
@@ -0,0 +1,25 @@
+#![allow(dead_code)]
+
+#[derive(Default)]
+struct V3 {
+    x: f32,
+    y: f32,
+    z: f32,
+}
+
+fn pz(v: V3) {
+    let _ = V3 { z: 0.0, ...v};
+    //~^ ERROR expected `..`
+
+    let _ = V3 { z: 0.0, ...Default::default() };
+    //~^ ERROR expected `..`
+
+    let _ = V3 { z: 0.0, ... };
+    //~^ expected identifier
+    //~| ERROR missing fields `x` and `y` in initializer of `V3`
+
+    let V3 { z: val, ... } = v;
+    //~^ ERROR expected field pattern
+}
+
+fn main() {}
diff --git a/src/test/ui/parser/issue-102806.stderr b/src/test/ui/parser/issue-102806.stderr
new file mode 100644
index 000000000000..6872b8bc0afe
--- /dev/null
+++ b/src/test/ui/parser/issue-102806.stderr
@@ -0,0 +1,45 @@
+error: expected `..`, found `...`
+  --> $DIR/issue-102806.rs:11:26
+   |
+LL |     let _ = V3 { z: 0.0, ...v};
+   |                          ^^^
+   |
+help: use `..` to fill in the rest of the fields
+   |
+LL |     let _ = V3 { z: 0.0, ..v};
+   |                          ~~
+
+error: expected `..`, found `...`
+  --> $DIR/issue-102806.rs:14:26
+   |
+LL |     let _ = V3 { z: 0.0, ...Default::default() };
+   |                          ^^^
+   |
+help: use `..` to fill in the rest of the fields
+   |
+LL |     let _ = V3 { z: 0.0, ..Default::default() };
+   |                          ~~
+
+error: expected identifier, found `...`
+  --> $DIR/issue-102806.rs:17:26
+   |
+LL |     let _ = V3 { z: 0.0, ... };
+   |             --           ^^^ expected identifier
+   |             |
+   |             while parsing this struct
+
+error: expected field pattern, found `...`
+  --> $DIR/issue-102806.rs:21:22
+   |
+LL |     let V3 { z: val, ... } = v;
+   |                      ^^^ help: to omit remaining fields, use one fewer `.`: `..`
+
+error[E0063]: missing fields `x` and `y` in initializer of `V3`
+  --> $DIR/issue-102806.rs:17:13
+   |
+LL |     let _ = V3 { z: 0.0, ... };
+   |             ^^ missing `x` and `y`
+
+error: aborting due to 5 previous errors
+
+For more information about this error, try `rustc --explain E0063`.
diff --git a/src/test/ui/parser/issue-103143.rs b/src/test/ui/parser/issue-103143.rs
new file mode 100644
index 000000000000..a584274c4051
--- /dev/null
+++ b/src/test/ui/parser/issue-103143.rs
@@ -0,0 +1,5 @@
+fn main() {
+    x::<#[a]y::<z>>
+    //~^ ERROR invalid const generic expression
+    //~| ERROR cannot find value `x` in this scope
+}
diff --git a/src/test/ui/parser/issue-103143.stderr b/src/test/ui/parser/issue-103143.stderr
new file mode 100644
index 000000000000..4035c69afa71
--- /dev/null
+++ b/src/test/ui/parser/issue-103143.stderr
@@ -0,0 +1,20 @@
+error: invalid const generic expression
+  --> $DIR/issue-103143.rs:2:13
+   |
+LL |     x::<#[a]y::<z>>
+   |             ^^^^^^
+   |
+help: expressions must be enclosed in braces to be used as const generic arguments
+   |
+LL |     x::<#[a]{ y::<z> }>
+   |             +        +
+
+error[E0425]: cannot find value `x` in this scope
+  --> $DIR/issue-103143.rs:2:5
+   |
+LL |     x::<#[a]y::<z>>
+   |     ^ not found in this scope
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0425`.
diff --git a/src/test/ui/parser/issue-103425.rs b/src/test/ui/parser/issue-103425.rs
new file mode 100644
index 000000000000..c2f8123ca4e6
--- /dev/null
+++ b/src/test/ui/parser/issue-103425.rs
@@ -0,0 +1,15 @@
+fn f() -> f32 {
+    3
+    //~^ ERROR expected `;`
+    5.0
+}
+
+fn k() -> f32 {
+    2_u32
+    //~^ ERROR expected `;`
+    3_i8
+    //~^ ERROR expected `;`
+    5.0
+}
+
+fn main() {}
diff --git a/src/test/ui/parser/issue-103425.stderr b/src/test/ui/parser/issue-103425.stderr
new file mode 100644
index 000000000000..0efe3e3ca711
--- /dev/null
+++ b/src/test/ui/parser/issue-103425.stderr
@@ -0,0 +1,29 @@
+error: expected `;`, found `5.0`
+  --> $DIR/issue-103425.rs:2:6
+   |
+LL |     3
+   |      ^ help: add `;` here
+LL |
+LL |     5.0
+   |     --- unexpected token
+
+error: expected `;`, found `3_i8`
+  --> $DIR/issue-103425.rs:8:10
+   |
+LL |     2_u32
+   |          ^ help: add `;` here
+LL |
+LL |     3_i8
+   |     ---- unexpected token
+
+error: expected `;`, found `5.0`
+  --> $DIR/issue-103425.rs:10:9
+   |
+LL |     3_i8
+   |         ^ help: add `;` here
+LL |
+LL |     5.0
+   |     --- unexpected token
+
+error: aborting due to 3 previous errors
+
diff --git a/src/test/ui/parser/issue-103451.rs b/src/test/ui/parser/issue-103451.rs
new file mode 100644
index 000000000000..1fdb00148815
--- /dev/null
+++ b/src/test/ui/parser/issue-103451.rs
@@ -0,0 +1,5 @@
+// error-pattern: this file contains an unclosed delimiter
+// error-pattern: expected value, found struct `R`
+struct R { }
+struct S {
+    x: [u8; R
diff --git a/src/test/ui/parser/issue-103451.stderr b/src/test/ui/parser/issue-103451.stderr
new file mode 100644
index 000000000000..eb3c92fb43d9
--- /dev/null
+++ b/src/test/ui/parser/issue-103451.stderr
@@ -0,0 +1,32 @@
+error: this file contains an unclosed delimiter
+  --> $DIR/issue-103451.rs:5:15
+   |
+LL | struct S {
+   |          - unclosed delimiter
+LL |     x: [u8; R
+   |        -      ^
+   |        |
+   |        unclosed delimiter
+
+error: this file contains an unclosed delimiter
+  --> $DIR/issue-103451.rs:5:15
+   |
+LL | struct S {
+   |          - unclosed delimiter
+LL |     x: [u8; R
+   |        -      ^
+   |        |
+   |        unclosed delimiter
+
+error[E0423]: expected value, found struct `R`
+  --> $DIR/issue-103451.rs:5:13
+   |
+LL | struct R { }
+   | ------------ `R` defined here
+LL | struct S {
+LL |     x: [u8; R
+   |             ^ help: use struct literal syntax instead: `R {}`
+
+error: aborting due to 3 previous errors
+
+For more information about this error, try `rustc --explain E0423`.
diff --git a/src/test/ui/parser/issue-103748-ICE-wrong-braces.rs b/src/test/ui/parser/issue-103748-ICE-wrong-braces.rs
new file mode 100644
index 000000000000..8012cb652bd8
--- /dev/null
+++ b/src/test/ui/parser/issue-103748-ICE-wrong-braces.rs
@@ -0,0 +1,8 @@
+#![crate_type = "lib"]
+
+struct Apple((Apple, Option(Banana ? Citron)));
+//~^ ERROR invalid `?` in type
+//~| ERROR expected one of `)` or `,`, found `Citron`
+//~| ERROR cannot find type `Citron` in this scope [E0412]
+//~| ERROR parenthesized type parameters may only be used with a `Fn` trait [E0214]
+//~| ERROR recursive type `Apple` has infinite size [E0072]
diff --git a/src/test/ui/parser/issue-103748-ICE-wrong-braces.stderr b/src/test/ui/parser/issue-103748-ICE-wrong-braces.stderr
new file mode 100644
index 000000000000..b0d8b03ae08c
--- /dev/null
+++ b/src/test/ui/parser/issue-103748-ICE-wrong-braces.stderr
@@ -0,0 +1,51 @@
+error: invalid `?` in type
+  --> $DIR/issue-103748-ICE-wrong-braces.rs:3:36
+   |
+LL | struct Apple((Apple, Option(Banana ? Citron)));
+   |                                    ^ `?` is only allowed on expressions, not types
+   |
+help: if you meant to express that the type might not contain a value, use the `Option` wrapper type
+   |
+LL | struct Apple((Apple, Option(Option<Banana > Citron)));
+   |                             +++++++       ~
+
+error: expected one of `)` or `,`, found `Citron`
+  --> $DIR/issue-103748-ICE-wrong-braces.rs:3:38
+   |
+LL | struct Apple((Apple, Option(Banana ? Citron)));
+   |                                     -^^^^^^ expected one of `)` or `,`
+   |                                     |
+   |                                     help: missing `,`
+
+error[E0412]: cannot find type `Citron` in this scope
+  --> $DIR/issue-103748-ICE-wrong-braces.rs:3:38
+   |
+LL | struct Apple((Apple, Option(Banana ? Citron)));
+   |                                      ^^^^^^ not found in this scope
+
+error[E0214]: parenthesized type parameters may only be used with a `Fn` trait
+  --> $DIR/issue-103748-ICE-wrong-braces.rs:3:22
+   |
+LL | struct Apple((Apple, Option(Banana ? Citron)));
+   |                      ^^^^^^^^^^^^^^^^^^^^^^^ only `Fn` traits may use parentheses
+   |
+help: use angle brackets instead
+   |
+LL | struct Apple((Apple, Option<Banana ? Citron>));
+   |                            ~               ~
+
+error[E0072]: recursive type `Apple` has infinite size
+  --> $DIR/issue-103748-ICE-wrong-braces.rs:3:1
+   |
+LL | struct Apple((Apple, Option(Banana ? Citron)));
+   | ^^^^^^^^^^^^  ----- recursive without indirection
+   |
+help: insert some indirection (e.g., a `Box`, `Rc`, or `&`) to break the cycle
+   |
+LL | struct Apple((Box<Apple>, Option(Banana ? Citron)));
+   |               ++++     +
+
+error: aborting due to 5 previous errors
+
+Some errors have detailed explanations: E0072, E0214, E0412.
+For more information about an error, try `rustc --explain E0072`.
diff --git a/src/test/ui/parser/issues/issue-104088.rs b/src/test/ui/parser/issues/issue-104088.rs
new file mode 100644
index 000000000000..5f794fe2dc92
--- /dev/null
+++ b/src/test/ui/parser/issues/issue-104088.rs
@@ -0,0 +1,26 @@
+fn test() {
+    if let 123 = 123 { println!("yes"); }
+}
+
+fn test_2() {
+    let 1x = 123;
+    //~^ ERROR expected identifier, found number literal
+}
+
+fn test_3() {
+    let 2x: i32 = 123;
+    //~^ ERROR expected identifier, found number literal
+}
+
+fn test_4() {
+    if let 2e1 = 123 {
+        //~^ ERROR mismatched types
+    }
+}
+
+fn test_5() {
+    let 23name = 123;
+    //~^ ERROR expected identifier, found number literal
+}
+
+fn main() {}
diff --git a/src/test/ui/parser/issues/issue-104088.stderr b/src/test/ui/parser/issues/issue-104088.stderr
new file mode 100644
index 000000000000..ff4b4bdb6953
--- /dev/null
+++ b/src/test/ui/parser/issues/issue-104088.stderr
@@ -0,0 +1,29 @@
+error: expected identifier, found number literal
+  --> $DIR/issue-104088.rs:6:9
+   |
+LL |     let 1x = 123;
+   |         ^^ identifiers cannot start with a number
+
+error: expected identifier, found number literal
+  --> $DIR/issue-104088.rs:11:9
+   |
+LL |     let 2x: i32 = 123;
+   |         ^^ identifiers cannot start with a number
+
+error: expected identifier, found number literal
+  --> $DIR/issue-104088.rs:22:9
+   |
+LL |     let 23name = 123;
+   |         ^^^^^^ identifiers cannot start with a number
+
+error[E0308]: mismatched types
+  --> $DIR/issue-104088.rs:16:12
+   |
+LL |     if let 2e1 = 123 {
+   |            ^^^   --- this expression has type `{integer}`
+   |            |
+   |            expected integer, found floating-point number
+
+error: aborting due to 4 previous errors
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/ui/parser/issues/issue-17383.rs b/src/test/ui/parser/issues/issue-17383.rs
deleted file mode 100644
index 7bf0e64f2c0a..000000000000
--- a/src/test/ui/parser/issues/issue-17383.rs
+++ /dev/null
@@ -1,7 +0,0 @@
-enum X {
-    A = 3,
-    //~^ ERROR custom discriminant values are not allowed in enums with tuple or struct variants
-    B(usize)
-}
-
-fn main() {}
diff --git a/src/test/ui/parser/issues/issue-17383.stderr b/src/test/ui/parser/issues/issue-17383.stderr
deleted file mode 100644
index 265d6e148661..000000000000
--- a/src/test/ui/parser/issues/issue-17383.stderr
+++ /dev/null
@@ -1,15 +0,0 @@
-error[E0658]: custom discriminant values are not allowed in enums with tuple or struct variants
-  --> $DIR/issue-17383.rs:2:9
-   |
-LL |     A = 3,
-   |         ^ disallowed custom discriminant
-LL |
-LL |     B(usize)
-   |     -------- tuple variant defined here
-   |
-   = note: see issue #60553 <https://github.com/rust-lang/rust/issues/60553> for more information
-   = help: add `#![feature(arbitrary_enum_discriminant)]` to the crate attributes to enable
-
-error: aborting due to previous error
-
-For more information about this error, try `rustc --explain E0658`.
diff --git a/src/test/ui/parser/item-kw-case-mismatch.fixed b/src/test/ui/parser/item-kw-case-mismatch.fixed
new file mode 100644
index 000000000000..1794268f260e
--- /dev/null
+++ b/src/test/ui/parser/item-kw-case-mismatch.fixed
@@ -0,0 +1,34 @@
+// run-rustfix
+// edition:2018
+#![allow(unused_imports)]
+
+fn main() {}
+
+use std::ptr::read;  //~ ERROR keyword `use` is written in a wrong case
+use std::ptr::write; //~ ERROR keyword `use` is written in a wrong case
+
+async fn _a() {}
+//~^ ERROR keyword `fn` is written in a wrong case
+
+fn _b() {}
+//~^ ERROR keyword `fn` is written in a wrong case
+
+async fn _c() {}
+//~^ ERROR keyword `async` is written in a wrong case
+//~| ERROR keyword `fn` is written in a wrong case
+
+async fn _d() {}
+//~^ ERROR keyword `async` is written in a wrong case
+
+const unsafe fn _e() {}
+//~^ ERROR keyword `const` is written in a wrong case
+//~| ERROR keyword `unsafe` is written in a wrong case
+//~| ERROR keyword `fn` is written in a wrong case
+
+unsafe extern fn _f() {}
+//~^ ERROR keyword `unsafe` is written in a wrong case
+//~| ERROR keyword `extern` is written in a wrong case
+
+extern "C" fn _g() {}
+//~^ ERROR keyword `extern` is written in a wrong case
+//~| ERROR keyword `fn` is written in a wrong case
diff --git a/src/test/ui/parser/item-kw-case-mismatch.rs b/src/test/ui/parser/item-kw-case-mismatch.rs
new file mode 100644
index 000000000000..ac8390efdb9a
--- /dev/null
+++ b/src/test/ui/parser/item-kw-case-mismatch.rs
@@ -0,0 +1,34 @@
+// run-rustfix
+// edition:2018
+#![allow(unused_imports)]
+
+fn main() {}
+
+Use std::ptr::read;  //~ ERROR keyword `use` is written in a wrong case
+USE std::ptr::write; //~ ERROR keyword `use` is written in a wrong case
+
+async Fn _a() {}
+//~^ ERROR keyword `fn` is written in a wrong case
+
+Fn _b() {}
+//~^ ERROR keyword `fn` is written in a wrong case
+
+aSYNC fN _c() {}
+//~^ ERROR keyword `async` is written in a wrong case
+//~| ERROR keyword `fn` is written in a wrong case
+
+Async fn _d() {}
+//~^ ERROR keyword `async` is written in a wrong case
+
+CONST UNSAFE FN _e() {}
+//~^ ERROR keyword `const` is written in a wrong case
+//~| ERROR keyword `unsafe` is written in a wrong case
+//~| ERROR keyword `fn` is written in a wrong case
+
+unSAFE EXTern fn _f() {}
+//~^ ERROR keyword `unsafe` is written in a wrong case
+//~| ERROR keyword `extern` is written in a wrong case
+
+EXTERN "C" FN _g() {}
+//~^ ERROR keyword `extern` is written in a wrong case
+//~| ERROR keyword `fn` is written in a wrong case
diff --git a/src/test/ui/parser/item-kw-case-mismatch.stderr b/src/test/ui/parser/item-kw-case-mismatch.stderr
new file mode 100644
index 000000000000..e66dae825f9c
--- /dev/null
+++ b/src/test/ui/parser/item-kw-case-mismatch.stderr
@@ -0,0 +1,86 @@
+error: keyword `use` is written in a wrong case
+  --> $DIR/item-kw-case-mismatch.rs:7:1
+   |
+LL | Use std::ptr::read;
+   | ^^^ help: write it in the correct case (notice the capitalization): `use`
+
+error: keyword `use` is written in a wrong case
+  --> $DIR/item-kw-case-mismatch.rs:8:1
+   |
+LL | USE std::ptr::write;
+   | ^^^ help: write it in the correct case: `use`
+
+error: keyword `fn` is written in a wrong case
+  --> $DIR/item-kw-case-mismatch.rs:10:7
+   |
+LL | async Fn _a() {}
+   |       ^^ help: write it in the correct case (notice the capitalization): `fn`
+
+error: keyword `fn` is written in a wrong case
+  --> $DIR/item-kw-case-mismatch.rs:13:1
+   |
+LL | Fn _b() {}
+   | ^^ help: write it in the correct case (notice the capitalization): `fn`
+
+error: keyword `async` is written in a wrong case
+  --> $DIR/item-kw-case-mismatch.rs:16:1
+   |
+LL | aSYNC fN _c() {}
+   | ^^^^^ help: write it in the correct case: `async`
+
+error: keyword `fn` is written in a wrong case
+  --> $DIR/item-kw-case-mismatch.rs:16:7
+   |
+LL | aSYNC fN _c() {}
+   |       ^^ help: write it in the correct case: `fn`
+
+error: keyword `async` is written in a wrong case
+  --> $DIR/item-kw-case-mismatch.rs:20:1
+   |
+LL | Async fn _d() {}
+   | ^^^^^ help: write it in the correct case: `async`
+
+error: keyword `const` is written in a wrong case
+  --> $DIR/item-kw-case-mismatch.rs:23:1
+   |
+LL | CONST UNSAFE FN _e() {}
+   | ^^^^^ help: write it in the correct case: `const`
+
+error: keyword `unsafe` is written in a wrong case
+  --> $DIR/item-kw-case-mismatch.rs:23:7
+   |
+LL | CONST UNSAFE FN _e() {}
+   |       ^^^^^^ help: write it in the correct case: `unsafe`
+
+error: keyword `fn` is written in a wrong case
+  --> $DIR/item-kw-case-mismatch.rs:23:14
+   |
+LL | CONST UNSAFE FN _e() {}
+   |              ^^ help: write it in the correct case: `fn`
+
+error: keyword `unsafe` is written in a wrong case
+  --> $DIR/item-kw-case-mismatch.rs:28:1
+   |
+LL | unSAFE EXTern fn _f() {}
+   | ^^^^^^ help: write it in the correct case: `unsafe`
+
+error: keyword `extern` is written in a wrong case
+  --> $DIR/item-kw-case-mismatch.rs:28:8
+   |
+LL | unSAFE EXTern fn _f() {}
+   |        ^^^^^^ help: write it in the correct case: `extern`
+
+error: keyword `extern` is written in a wrong case
+  --> $DIR/item-kw-case-mismatch.rs:32:1
+   |
+LL | EXTERN "C" FN _g() {}
+   | ^^^^^^ help: write it in the correct case: `extern`
+
+error: keyword `fn` is written in a wrong case
+  --> $DIR/item-kw-case-mismatch.rs:32:12
+   |
+LL | EXTERN "C" FN _g() {}
+   |            ^^ help: write it in the correct case: `fn`
+
+error: aborting due to 14 previous errors
+
diff --git a/src/test/ui/parser/kw-in-trait-bounds.stderr b/src/test/ui/parser/kw-in-trait-bounds.stderr
index 28196c7ce2de..546ad84eeee7 100644
--- a/src/test/ui/parser/kw-in-trait-bounds.stderr
+++ b/src/test/ui/parser/kw-in-trait-bounds.stderr
@@ -94,8 +94,8 @@ LL | fn _f<F: fn(), G>(_: impl fn(), _: &dyn fn())
    |
   ::: $SRC_DIR/core/src/ops/function.rs:LL:COL
    |
-LL | pub trait Fn<Args>: FnMut<Args> {
-   | ------------------------------- similarly named trait `Fn` defined here
+LL | pub trait Fn<Args: Tuple>: FnMut<Args> {
+   | -------------------------------------- similarly named trait `Fn` defined here
 
 error[E0405]: cannot find trait `r#fn` in this scope
   --> $DIR/kw-in-trait-bounds.rs:17:4
@@ -105,8 +105,8 @@ LL | G: fn(),
    |
   ::: $SRC_DIR/core/src/ops/function.rs:LL:COL
    |
-LL | pub trait Fn<Args>: FnMut<Args> {
-   | ------------------------------- similarly named trait `Fn` defined here
+LL | pub trait Fn<Args: Tuple>: FnMut<Args> {
+   | -------------------------------------- similarly named trait `Fn` defined here
 
 error[E0405]: cannot find trait `r#fn` in this scope
   --> $DIR/kw-in-trait-bounds.rs:3:27
@@ -116,8 +116,8 @@ LL | fn _f<F: fn(), G>(_: impl fn(), _: &dyn fn())
    |
   ::: $SRC_DIR/core/src/ops/function.rs:LL:COL
    |
-LL | pub trait Fn<Args>: FnMut<Args> {
-   | ------------------------------- similarly named trait `Fn` defined here
+LL | pub trait Fn<Args: Tuple>: FnMut<Args> {
+   | -------------------------------------- similarly named trait `Fn` defined here
 
 error[E0405]: cannot find trait `r#fn` in this scope
   --> $DIR/kw-in-trait-bounds.rs:3:41
@@ -127,8 +127,8 @@ LL | fn _f<F: fn(), G>(_: impl fn(), _: &dyn fn())
    |
   ::: $SRC_DIR/core/src/ops/function.rs:LL:COL
    |
-LL | pub trait Fn<Args>: FnMut<Args> {
-   | ------------------------------- similarly named trait `Fn` defined here
+LL | pub trait Fn<Args: Tuple>: FnMut<Args> {
+   | -------------------------------------- similarly named trait `Fn` defined here
 
 error[E0405]: cannot find trait `r#struct` in this scope
   --> $DIR/kw-in-trait-bounds.rs:24:10
diff --git a/src/test/ui/parser/label-after-block-like.rs b/src/test/ui/parser/label-after-block-like.rs
new file mode 100644
index 000000000000..55f3f8f9f5f0
--- /dev/null
+++ b/src/test/ui/parser/label-after-block-like.rs
@@ -0,0 +1,43 @@
+fn a() {
+    if let () = () 'a {}
+    //~^ ERROR labeled expression must be followed by `:`
+    //~| ERROR expected `{`, found `'a`
+}
+
+fn b() {
+    if true 'a {}
+    //~^ ERROR labeled expression must be followed by `:`
+    //~| ERROR expected `{`, found `'a`
+}
+
+fn c() {
+    loop 'a {}
+    //~^ ERROR labeled expression must be followed by `:`
+    //~| ERROR expected `{`, found `'a`
+}
+
+fn d() {
+    while true 'a {}
+    //~^ ERROR labeled expression must be followed by `:`
+    //~| ERROR expected `{`, found `'a`
+}
+
+fn e() {
+    while let () = () 'a {}
+    //~^ ERROR labeled expression must be followed by `:`
+    //~| ERROR expected `{`, found `'a`
+}
+
+fn f() {
+    for _ in 0..0 'a {}
+    //~^ ERROR labeled expression must be followed by `:`
+    //~| ERROR expected `{`, found `'a`
+}
+
+fn g() {
+    unsafe 'a {}
+    //~^ ERROR labeled expression must be followed by `:`
+    //~| ERROR expected `{`, found `'a`
+}
+
+fn main() {}
diff --git a/src/test/ui/parser/label-after-block-like.stderr b/src/test/ui/parser/label-after-block-like.stderr
new file mode 100644
index 000000000000..8ff50b124b32
--- /dev/null
+++ b/src/test/ui/parser/label-after-block-like.stderr
@@ -0,0 +1,176 @@
+error: labeled expression must be followed by `:`
+  --> $DIR/label-after-block-like.rs:2:20
+   |
+LL |     if let () = () 'a {}
+   |                    ---^^
+   |                    | |
+   |                    | help: add `:` after the label
+   |                    the label
+   |
+   = note: labels are used before loops and blocks, allowing e.g., `break 'label` to them
+
+error: expected `{`, found `'a`
+  --> $DIR/label-after-block-like.rs:2:20
+   |
+LL |     if let () = () 'a {}
+   |                    ^^ expected `{`
+   |
+note: the `if` expression is missing a block after this condition
+  --> $DIR/label-after-block-like.rs:2:8
+   |
+LL |     if let () = () 'a {}
+   |        ^^^^^^^^^^^
+help: try placing this code inside a block
+   |
+LL |     if let () = () { 'a {} }
+   |                    +       +
+
+error: labeled expression must be followed by `:`
+  --> $DIR/label-after-block-like.rs:8:13
+   |
+LL |     if true 'a {}
+   |             ---^^
+   |             | |
+   |             | help: add `:` after the label
+   |             the label
+   |
+   = note: labels are used before loops and blocks, allowing e.g., `break 'label` to them
+
+error: expected `{`, found `'a`
+  --> $DIR/label-after-block-like.rs:8:13
+   |
+LL |     if true 'a {}
+   |             ^^ expected `{`
+   |
+note: the `if` expression is missing a block after this condition
+  --> $DIR/label-after-block-like.rs:8:8
+   |
+LL |     if true 'a {}
+   |        ^^^^
+help: try placing this code inside a block
+   |
+LL |     if true { 'a {} }
+   |             +       +
+
+error: labeled expression must be followed by `:`
+  --> $DIR/label-after-block-like.rs:14:10
+   |
+LL |     loop 'a {}
+   |          ---^^
+   |          | |
+   |          | help: add `:` after the label
+   |          the label
+   |
+   = note: labels are used before loops and blocks, allowing e.g., `break 'label` to them
+
+error: expected `{`, found `'a`
+  --> $DIR/label-after-block-like.rs:14:10
+   |
+LL |     loop 'a {}
+   |     ---- ^^ expected `{`
+   |     |
+   |     while parsing this `loop` expression
+   |
+help: try placing this code inside a block
+   |
+LL |     loop { 'a {} }
+   |          +       +
+
+error: labeled expression must be followed by `:`
+  --> $DIR/label-after-block-like.rs:20:16
+   |
+LL |     while true 'a {}
+   |                ---^^
+   |                | |
+   |                | help: add `:` after the label
+   |                the label
+   |
+   = note: labels are used before loops and blocks, allowing e.g., `break 'label` to them
+
+error: expected `{`, found `'a`
+  --> $DIR/label-after-block-like.rs:20:16
+   |
+LL |     while true 'a {}
+   |     ----- ---- ^^ expected `{`
+   |     |     |
+   |     |     this `while` condition successfully parsed
+   |     while parsing the body of this `while` expression
+   |
+help: try placing this code inside a block
+   |
+LL |     while true { 'a {} }
+   |                +       +
+
+error: labeled expression must be followed by `:`
+  --> $DIR/label-after-block-like.rs:26:23
+   |
+LL |     while let () = () 'a {}
+   |                       ---^^
+   |                       | |
+   |                       | help: add `:` after the label
+   |                       the label
+   |
+   = note: labels are used before loops and blocks, allowing e.g., `break 'label` to them
+
+error: expected `{`, found `'a`
+  --> $DIR/label-after-block-like.rs:26:23
+   |
+LL |     while let () = () 'a {}
+   |     ----- ----------- ^^ expected `{`
+   |     |     |
+   |     |     this `while` condition successfully parsed
+   |     while parsing the body of this `while` expression
+   |
+help: try placing this code inside a block
+   |
+LL |     while let () = () { 'a {} }
+   |                       +       +
+
+error: labeled expression must be followed by `:`
+  --> $DIR/label-after-block-like.rs:32:19
+   |
+LL |     for _ in 0..0 'a {}
+   |                   ---^^
+   |                   | |
+   |                   | help: add `:` after the label
+   |                   the label
+   |
+   = note: labels are used before loops and blocks, allowing e.g., `break 'label` to them
+
+error: expected `{`, found `'a`
+  --> $DIR/label-after-block-like.rs:32:19
+   |
+LL |     for _ in 0..0 'a {}
+   |                   ^^ expected `{`
+   |
+help: try placing this code inside a block
+   |
+LL |     for _ in 0..0 { 'a {} }
+   |                   +       +
+
+error: labeled expression must be followed by `:`
+  --> $DIR/label-after-block-like.rs:38:12
+   |
+LL |     unsafe 'a {}
+   |            ---^^
+   |            | |
+   |            | help: add `:` after the label
+   |            the label
+   |
+   = note: labels are used before loops and blocks, allowing e.g., `break 'label` to them
+
+error: expected `{`, found `'a`
+  --> $DIR/label-after-block-like.rs:38:12
+   |
+LL |     unsafe 'a {}
+   |     ------ ^^ expected `{`
+   |     |
+   |     while parsing this `unsafe` expression
+   |
+help: try placing this code inside a block
+   |
+LL |     unsafe { 'a {} }
+   |            +       +
+
+error: aborting due to 14 previous errors
+
diff --git a/src/test/ui/parser/macro/macro-doc-comments-1.stderr b/src/test/ui/parser/macro/macro-doc-comments-1.stderr
index 0ebf3d52b637..eaeb62d2cfd9 100644
--- a/src/test/ui/parser/macro/macro-doc-comments-1.stderr
+++ b/src/test/ui/parser/macro/macro-doc-comments-1.stderr
@@ -9,6 +9,12 @@ LL |     //! Inner
    |     |
    |     no rules expected this token in macro call
    |     inner doc comments expand to `#![doc = "..."]`, which is what this macro attempted to match
+   |
+note: while trying to match `[`
+  --> $DIR/macro-doc-comments-1.rs:2:7
+   |
+LL |     (#[$outer:meta]) => ()
+   |       ^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/parser/macro/macro-doc-comments-2.stderr b/src/test/ui/parser/macro/macro-doc-comments-2.stderr
index 346d865868d9..1dcd95f6fad4 100644
--- a/src/test/ui/parser/macro/macro-doc-comments-2.stderr
+++ b/src/test/ui/parser/macro/macro-doc-comments-2.stderr
@@ -9,6 +9,12 @@ LL |     /// Outer
    |     |
    |     no rules expected this token in macro call
    |     outer doc comments expand to `#[doc = "..."]`, which is what this macro attempted to match
+   |
+note: while trying to match `!`
+  --> $DIR/macro-doc-comments-2.rs:2:7
+   |
+LL |     (#![$inner:meta]) => ()
+   |       ^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/parser/raw/raw-byte-string-literals.rs b/src/test/ui/parser/raw/raw-byte-string-literals.rs
index 163c8ac66b02..1b859fee596a 100644
--- a/src/test/ui/parser/raw/raw-byte-string-literals.rs
+++ b/src/test/ui/parser/raw/raw-byte-string-literals.rs
@@ -2,6 +2,6 @@
 
 pub fn main() {
     br"a
"; //~ ERROR bare CR not allowed in raw string
-    br"é";  //~ ERROR raw byte string must be ASCII
+    br"é";  //~ ERROR non-ASCII character in raw byte string literal
     br##~"a"~##;  //~ ERROR only `#` is allowed in raw string delimitation
 }
diff --git a/src/test/ui/parser/raw/raw-byte-string-literals.stderr b/src/test/ui/parser/raw/raw-byte-string-literals.stderr
index cfc877104bd9..a2f27d1ed70a 100644
--- a/src/test/ui/parser/raw/raw-byte-string-literals.stderr
+++ b/src/test/ui/parser/raw/raw-byte-string-literals.stderr
@@ -4,7 +4,7 @@ error: bare CR not allowed in raw string
 LL |     br"a
";
    |         ^
 
-error: raw byte string must be ASCII
+error: non-ASCII character in raw byte string literal
   --> $DIR/raw-byte-string-literals.rs:5:8
    |
 LL |     br"é";
diff --git a/src/test/ui/parser/recover-fn-ptr-with-generics.rs b/src/test/ui/parser/recover-fn-ptr-with-generics.rs
new file mode 100644
index 000000000000..31de418be5f7
--- /dev/null
+++ b/src/test/ui/parser/recover-fn-ptr-with-generics.rs
@@ -0,0 +1,31 @@
+fn main() {
+    type Predicate = fn<'a>(&'a str) -> bool;
+    //~^ ERROR function pointer types may not have generic parameters
+
+    type Identity = fn<T>(T) -> T;
+    //~^ ERROR function pointer types may not have generic parameters
+    //~| ERROR cannot find type `T` in this scope
+    //~| ERROR cannot find type `T` in this scope
+
+    let _: fn<const N: usize, 'e, Q, 'f>();
+    //~^ ERROR function pointer types may not have generic parameters
+
+    let _: for<'outer> fn<'inner>();
+    //~^ ERROR function pointer types may not have generic parameters
+
+    let _: for<> fn<'r>();
+    //~^ ERROR function pointer types may not have generic parameters
+
+    type Hmm = fn<>();
+    //~^ ERROR function pointer types may not have generic parameters
+
+    let _: extern fn<'a: 'static>();
+    //~^ ERROR function pointer types may not have generic parameters
+    //~| ERROR lifetime bounds cannot be used in this context
+
+    let _: for<'any> extern "C" fn<'u>();
+    //~^ ERROR function pointer types may not have generic parameters
+
+    type QuiteBroken = fn<const>();
+    //~^ ERROR expected identifier, found `>`
+}
diff --git a/src/test/ui/parser/recover-fn-ptr-with-generics.stderr b/src/test/ui/parser/recover-fn-ptr-with-generics.stderr
new file mode 100644
index 000000000000..1da9c18571b9
--- /dev/null
+++ b/src/test/ui/parser/recover-fn-ptr-with-generics.stderr
@@ -0,0 +1,111 @@
+error: function pointer types may not have generic parameters
+  --> $DIR/recover-fn-ptr-with-generics.rs:2:24
+   |
+LL |     type Predicate = fn<'a>(&'a str) -> bool;
+   |                        ^^^^
+   |
+help: consider moving the lifetime parameter to a `for` parameter list
+   |
+LL -     type Predicate = fn<'a>(&'a str) -> bool;
+LL +     type Predicate = for<'a> fn(&'a str) -> bool;
+   |
+
+error: function pointer types may not have generic parameters
+  --> $DIR/recover-fn-ptr-with-generics.rs:5:23
+   |
+LL |     type Identity = fn<T>(T) -> T;
+   |                       ^^^
+
+error: function pointer types may not have generic parameters
+  --> $DIR/recover-fn-ptr-with-generics.rs:10:14
+   |
+LL |     let _: fn<const N: usize, 'e, Q, 'f>();
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: consider moving the lifetime parameters to a `for` parameter list
+   |
+LL -     let _: fn<const N: usize, 'e, Q, 'f>();
+LL +     let _: for<'e, 'f> fn();
+   |
+
+error: function pointer types may not have generic parameters
+  --> $DIR/recover-fn-ptr-with-generics.rs:13:26
+   |
+LL |     let _: for<'outer> fn<'inner>();
+   |                          ^^^^^^^^
+   |
+help: consider moving the lifetime parameter to the `for` parameter list
+   |
+LL -     let _: for<'outer> fn<'inner>();
+LL +     let _: for<'outer, 'inner> fn();
+   |
+
+error: function pointer types may not have generic parameters
+  --> $DIR/recover-fn-ptr-with-generics.rs:16:20
+   |
+LL |     let _: for<> fn<'r>();
+   |                    ^^^^
+   |
+help: consider moving the lifetime parameter to the `for` parameter list
+   |
+LL -     let _: for<> fn<'r>();
+LL +     let _: for<'r> fn();
+   |
+
+error: function pointer types may not have generic parameters
+  --> $DIR/recover-fn-ptr-with-generics.rs:19:18
+   |
+LL |     type Hmm = fn<>();
+   |                  ^^
+
+error: function pointer types may not have generic parameters
+  --> $DIR/recover-fn-ptr-with-generics.rs:22:21
+   |
+LL |     let _: extern fn<'a: 'static>();
+   |                     ^^^^^^^^^^^^^
+   |
+help: consider moving the lifetime parameter to a `for` parameter list
+   |
+LL -     let _: extern fn<'a: 'static>();
+LL +     let _: for<'a> extern fn();
+   |
+
+error: function pointer types may not have generic parameters
+  --> $DIR/recover-fn-ptr-with-generics.rs:26:35
+   |
+LL |     let _: for<'any> extern "C" fn<'u>();
+   |                                   ^^^^
+   |
+help: consider moving the lifetime parameter to the `for` parameter list
+   |
+LL -     let _: for<'any> extern "C" fn<'u>();
+LL +     let _: for<'any, 'u> extern "C" fn();
+   |
+
+error: expected identifier, found `>`
+  --> $DIR/recover-fn-ptr-with-generics.rs:29:32
+   |
+LL |     type QuiteBroken = fn<const>();
+   |                                ^ expected identifier
+
+error: lifetime bounds cannot be used in this context
+  --> $DIR/recover-fn-ptr-with-generics.rs:22:26
+   |
+LL |     let _: extern fn<'a: 'static>();
+   |                          ^^^^^^^
+
+error[E0412]: cannot find type `T` in this scope
+  --> $DIR/recover-fn-ptr-with-generics.rs:5:27
+   |
+LL |     type Identity = fn<T>(T) -> T;
+   |                           ^ not found in this scope
+
+error[E0412]: cannot find type `T` in this scope
+  --> $DIR/recover-fn-ptr-with-generics.rs:5:33
+   |
+LL |     type Identity = fn<T>(T) -> T;
+   |                                 ^ not found in this scope
+
+error: aborting due to 12 previous errors
+
+For more information about this error, try `rustc --explain E0412`.
diff --git a/src/test/ui/slowparse-bstring.rs b/src/test/ui/parser/slowparse-bstring.rs
similarity index 100%
rename from src/test/ui/slowparse-bstring.rs
rename to src/test/ui/parser/slowparse-bstring.rs
diff --git a/src/test/ui/slowparse-string.rs b/src/test/ui/parser/slowparse-string.rs
similarity index 100%
rename from src/test/ui/slowparse-string.rs
rename to src/test/ui/parser/slowparse-string.rs
diff --git a/src/test/ui/parser/tag-variant-disr-non-nullary.rs b/src/test/ui/parser/tag-variant-disr-non-nullary.rs
deleted file mode 100644
index a9cfdd549c75..000000000000
--- a/src/test/ui/parser/tag-variant-disr-non-nullary.rs
+++ /dev/null
@@ -1,12 +0,0 @@
-enum Color {
-    Red = 0xff0000,
-    //~^ ERROR custom discriminant values are not allowed in enums with tuple or struct variants
-    Green = 0x00ff00,
-    Blue = 0x0000ff,
-    Black = 0x000000,
-    White = 0xffffff,
-    Other(usize),
-    Other2(usize, usize),
-}
-
-fn main() {}
diff --git a/src/test/ui/parser/tag-variant-disr-non-nullary.stderr b/src/test/ui/parser/tag-variant-disr-non-nullary.stderr
deleted file mode 100644
index 79f044a0675b..000000000000
--- a/src/test/ui/parser/tag-variant-disr-non-nullary.stderr
+++ /dev/null
@@ -1,25 +0,0 @@
-error[E0658]: custom discriminant values are not allowed in enums with tuple or struct variants
-  --> $DIR/tag-variant-disr-non-nullary.rs:2:11
-   |
-LL |     Red = 0xff0000,
-   |           ^^^^^^^^ disallowed custom discriminant
-LL |
-LL |     Green = 0x00ff00,
-   |             ^^^^^^^^ disallowed custom discriminant
-LL |     Blue = 0x0000ff,
-   |            ^^^^^^^^ disallowed custom discriminant
-LL |     Black = 0x000000,
-   |             ^^^^^^^^ disallowed custom discriminant
-LL |     White = 0xffffff,
-   |             ^^^^^^^^ disallowed custom discriminant
-LL |     Other(usize),
-   |     ------------ tuple variant defined here
-LL |     Other2(usize, usize),
-   |     -------------------- tuple variant defined here
-   |
-   = note: see issue #60553 <https://github.com/rust-lang/rust/issues/60553> for more information
-   = help: add `#![feature(arbitrary_enum_discriminant)]` to the crate attributes to enable
-
-error: aborting due to previous error
-
-For more information about this error, try `rustc --explain E0658`.
diff --git a/src/test/ui/parser/underscore-suffix-for-string.rs b/src/test/ui/parser/underscore-suffix-for-string.rs
index 2e0ebe2cfa44..bd260752e04d 100644
--- a/src/test/ui/parser/underscore-suffix-for-string.rs
+++ b/src/test/ui/parser/underscore-suffix-for-string.rs
@@ -1,8 +1,17 @@
-// check-pass
+macro_rules! sink {
+    ($tt:tt) => {()}
+}
 
 fn main() {
     let _ = "Foo"_;
-    //~^ WARNING underscore literal suffix is not allowed
-    //~| WARNING this was previously accepted
-    //~| NOTE issue #42326
+    //~^ ERROR underscore literal suffix is not allowed
+
+    // This is ok, because `__` is a valid identifier and the macro consumes it
+    // before proper parsing happens.
+    let _ = sink!("Foo"__);
+
+    // This is not ok, even as an input to a macro, because the `_` suffix is
+    // never allowed.
+    sink!("Foo"_);
+    //~^ ERROR underscore literal suffix is not allowed
 }
diff --git a/src/test/ui/parser/underscore-suffix-for-string.stderr b/src/test/ui/parser/underscore-suffix-for-string.stderr
index 00c7657f17bd..2fe2c130eb21 100644
--- a/src/test/ui/parser/underscore-suffix-for-string.stderr
+++ b/src/test/ui/parser/underscore-suffix-for-string.stderr
@@ -1,11 +1,14 @@
-warning: underscore literal suffix is not allowed
-  --> $DIR/underscore-suffix-for-string.rs:4:18
+error: underscore literal suffix is not allowed
+  --> $DIR/underscore-suffix-for-string.rs:6:18
    |
 LL |     let _ = "Foo"_;
    |                  ^
+
+error: underscore literal suffix is not allowed
+  --> $DIR/underscore-suffix-for-string.rs:15:16
    |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: see issue #42326 <https://github.com/rust-lang/rust/issues/42326> for more information
+LL |     sink!("Foo"_);
+   |                ^
 
-warning: 1 warning emitted
+error: aborting due to 2 previous errors
 
diff --git a/src/test/ui/parser/unicode-control-codepoints.rs b/src/test/ui/parser/unicode-control-codepoints.rs
index 5af0b585a127..df099bb62ad1 100644
--- a/src/test/ui/parser/unicode-control-codepoints.rs
+++ b/src/test/ui/parser/unicode-control-codepoints.rs
@@ -14,15 +14,15 @@ fn main() {
     println!("{:?}", r##"/*‮ } ⁦if isAdmin⁩ ⁦ begin admins only "##);
     //~^ ERROR unicode codepoint changing visible direction of text present in literal
     println!("{:?}", b"/*‮ } ⁦if isAdmin⁩ ⁦ begin admins only ");
-    //~^ ERROR non-ASCII character in byte constant
-    //~| ERROR non-ASCII character in byte constant
-    //~| ERROR non-ASCII character in byte constant
-    //~| ERROR non-ASCII character in byte constant
+    //~^ ERROR non-ASCII character in byte string literal
+    //~| ERROR non-ASCII character in byte string literal
+    //~| ERROR non-ASCII character in byte string literal
+    //~| ERROR non-ASCII character in byte string literal
     println!("{:?}", br##"/*‮ } ⁦if isAdmin⁩ ⁦ begin admins only "##);
-    //~^ ERROR raw byte string must be ASCII
-    //~| ERROR raw byte string must be ASCII
-    //~| ERROR raw byte string must be ASCII
-    //~| ERROR raw byte string must be ASCII
+    //~^ ERROR non-ASCII character in raw byte string literal
+    //~| ERROR non-ASCII character in raw byte string literal
+    //~| ERROR non-ASCII character in raw byte string literal
+    //~| ERROR non-ASCII character in raw byte string literal
     println!("{:?}", '‮');
     //~^ ERROR unicode codepoint changing visible direction of text present in literal
 }
diff --git a/src/test/ui/parser/unicode-control-codepoints.stderr b/src/test/ui/parser/unicode-control-codepoints.stderr
index 44548c72ff5d..fc071a941914 100644
--- a/src/test/ui/parser/unicode-control-codepoints.stderr
+++ b/src/test/ui/parser/unicode-control-codepoints.stderr
@@ -14,69 +14,69 @@ LL |     println!("{:?}", b"us\u{202B}e\u{202A}r");
    |
    = help: unicode escape sequences cannot be used as a byte or in a byte string
 
-error: non-ASCII character in byte constant
+error: non-ASCII character in byte string literal
   --> $DIR/unicode-control-codepoints.rs:16:26
    |
 LL |     println!("{:?}", b"/* } if isAdmin  begin admins only ");
-   |                          ^ byte constant must be ASCII but is '\u{202e}'
+   |                          ^ must be ASCII but is '\u{202e}'
    |
 help: if you meant to use the UTF-8 encoding of '\u{202e}', use \xHH escapes
    |
 LL |     println!("{:?}", b"/*\xE2\x80\xAE } if isAdmin  begin admins only ");
    |                          ~~~~~~~~~~~~
 
-error: non-ASCII character in byte constant
+error: non-ASCII character in byte string literal
   --> $DIR/unicode-control-codepoints.rs:16:30
    |
 LL |     println!("{:?}", b"/* } if isAdmin  begin admins only ");
-   |                             ^ byte constant must be ASCII but is '\u{2066}'
+   |                             ^ must be ASCII but is '\u{2066}'
    |
 help: if you meant to use the UTF-8 encoding of '\u{2066}', use \xHH escapes
    |
 LL |     println!("{:?}", b"/* } \xE2\x81\xA6if isAdmin  begin admins only ");
    |                             ~~~~~~~~~~~~
 
-error: non-ASCII character in byte constant
+error: non-ASCII character in byte string literal
   --> $DIR/unicode-control-codepoints.rs:16:41
    |
 LL |     println!("{:?}", b"/* } if isAdmin  begin admins only ");
-   |                                       ^ byte constant must be ASCII but is '\u{2069}'
+   |                                       ^ must be ASCII but is '\u{2069}'
    |
 help: if you meant to use the UTF-8 encoding of '\u{2069}', use \xHH escapes
    |
 LL |     println!("{:?}", b"/* } if isAdmin\xE2\x81\xA9  begin admins only ");
    |                                       ~~~~~~~~~~~~
 
-error: non-ASCII character in byte constant
+error: non-ASCII character in byte string literal
   --> $DIR/unicode-control-codepoints.rs:16:43
    |
 LL |     println!("{:?}", b"/* } if isAdmin  begin admins only ");
-   |                                        ^ byte constant must be ASCII but is '\u{2066}'
+   |                                        ^ must be ASCII but is '\u{2066}'
    |
 help: if you meant to use the UTF-8 encoding of '\u{2066}', use \xHH escapes
    |
 LL |     println!("{:?}", b"/* } if isAdmin \xE2\x81\xA6 begin admins only ");
    |                                        ~~~~~~~~~~~~
 
-error: raw byte string must be ASCII
+error: non-ASCII character in raw byte string literal
   --> $DIR/unicode-control-codepoints.rs:21:29
    |
 LL |     println!("{:?}", br##"/* } if isAdmin  begin admins only "##);
    |                             ^ must be ASCII but is '\u{202e}'
 
-error: raw byte string must be ASCII
+error: non-ASCII character in raw byte string literal
   --> $DIR/unicode-control-codepoints.rs:21:33
    |
 LL |     println!("{:?}", br##"/* } if isAdmin  begin admins only "##);
    |                                ^ must be ASCII but is '\u{2066}'
 
-error: raw byte string must be ASCII
+error: non-ASCII character in raw byte string literal
   --> $DIR/unicode-control-codepoints.rs:21:44
    |
 LL |     println!("{:?}", br##"/* } if isAdmin  begin admins only "##);
    |                                          ^ must be ASCII but is '\u{2069}'
 
-error: raw byte string must be ASCII
+error: non-ASCII character in raw byte string literal
   --> $DIR/unicode-control-codepoints.rs:21:46
    |
 LL |     println!("{:?}", br##"/* } if isAdmin  begin admins only "##);
diff --git a/src/test/ui/parser/use-colon-as-mod-sep.rs b/src/test/ui/parser/use-colon-as-mod-sep.rs
new file mode 100644
index 000000000000..e1e8756b03c2
--- /dev/null
+++ b/src/test/ui/parser/use-colon-as-mod-sep.rs
@@ -0,0 +1,11 @@
+// Recover from using a colon as a path separator.
+
+use std::process:Command;
+//~^ ERROR expected `::`, found `:`
+use std:fs::File;
+//~^ ERROR expected `::`, found `:`
+use std:collections:HashMap;
+//~^ ERROR expected `::`, found `:`
+//~| ERROR expected `::`, found `:`
+
+fn main() { }
diff --git a/src/test/ui/parser/use-colon-as-mod-sep.stderr b/src/test/ui/parser/use-colon-as-mod-sep.stderr
new file mode 100644
index 000000000000..e825dfed1119
--- /dev/null
+++ b/src/test/ui/parser/use-colon-as-mod-sep.stderr
@@ -0,0 +1,28 @@
+error: expected `::`, found `:`
+  --> $DIR/use-colon-as-mod-sep.rs:3:17
+   |
+LL | use std::process:Command;
+   |                 ^ help: use double colon
+   |
+   = note: import paths are delimited using `::`
+
+error: expected `::`, found `:`
+  --> $DIR/use-colon-as-mod-sep.rs:5:8
+   |
+LL | use std:fs::File;
+   |        ^ help: use double colon
+
+error: expected `::`, found `:`
+  --> $DIR/use-colon-as-mod-sep.rs:7:8
+   |
+LL | use std:collections:HashMap;
+   |        ^ help: use double colon
+
+error: expected `::`, found `:`
+  --> $DIR/use-colon-as-mod-sep.rs:7:20
+   |
+LL | use std:collections:HashMap;
+   |                    ^ help: use double colon
+
+error: aborting due to 4 previous errors
+
diff --git a/src/test/ui/issues/issue-52240.rs b/src/test/ui/pattern/issue-52240.rs
similarity index 100%
rename from src/test/ui/issues/issue-52240.rs
rename to src/test/ui/pattern/issue-52240.rs
diff --git a/src/test/ui/issues/issue-52240.stderr b/src/test/ui/pattern/issue-52240.stderr
similarity index 100%
rename from src/test/ui/issues/issue-52240.stderr
rename to src/test/ui/pattern/issue-52240.stderr
diff --git a/src/test/ui/pin-macro/lifetime_errors_on_promotion_misusage.stderr b/src/test/ui/pin-macro/lifetime_errors_on_promotion_misusage.stderr
index 4971263af08a..fc1be052fb79 100644
--- a/src/test/ui/pin-macro/lifetime_errors_on_promotion_misusage.stderr
+++ b/src/test/ui/pin-macro/lifetime_errors_on_promotion_misusage.stderr
@@ -4,7 +4,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     let phantom_pinned = identity(pin!(PhantomPinned));
    |                                   ^^^^^^^^^^^^^^^^^^^ - temporary value is freed at the end of this statement
    |                                   |
-   |                                   creates a temporary which is freed while still in use
+   |                                   creates a temporary value which is freed while still in use
 LL |
 LL |     stuff(phantom_pinned)
    |           -------------- borrow later used here
@@ -18,7 +18,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     let phantom_pinned = {
    |         -------------- borrow later stored here
 LL |         let phantom_pinned = pin!(PhantomPinned);
-   |                              ^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |                              ^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
 ...
 LL |     };
    |     - temporary value is freed at the end of this statement
diff --git a/src/test/ui/privacy/access_levels.rs b/src/test/ui/privacy/access_levels.rs
deleted file mode 100644
index 42c9975bedb7..000000000000
--- a/src/test/ui/privacy/access_levels.rs
+++ /dev/null
@@ -1,75 +0,0 @@
-#![feature(rustc_attrs)]
-
-#[rustc_effective_visibility]
-mod outer { //~ ERROR Public: pub(crate), Exported: pub(crate), Reachable: pub(crate), ReachableFromImplTrait: pub(crate)
-    #[rustc_effective_visibility]
-    pub mod inner1 { //~ ERROR Public: pub(crate), Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-
-        #[rustc_effective_visibility]
-        extern "C" {} //~ ERROR Public: pub(crate), Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-
-        #[rustc_effective_visibility]
-        pub trait PubTrait { //~ ERROR Public: pub(crate), Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-            #[rustc_effective_visibility]
-            const A: i32; //~ ERROR Public: pub(crate), Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-            #[rustc_effective_visibility]
-            type B; //~ ERROR Public: pub(crate), Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-        }
-
-        #[rustc_effective_visibility]
-        struct PrivStruct; //~ ERROR Public: pub(self), Exported: pub(self), Reachable: pub(self), ReachableFromImplTrait: pub(self)
-
-        #[rustc_effective_visibility]
-        pub union PubUnion { //~ ERROR Public: pub(crate), Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-            #[rustc_effective_visibility]
-            a: u8, //~ ERROR Public: pub(self), Exported: pub(self), Reachable: pub(self), ReachableFromImplTrait: pub(self)
-            #[rustc_effective_visibility]
-            pub b: u8, //~ ERROR Public: pub(crate), Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-        }
-
-        #[rustc_effective_visibility]
-        pub enum Enum { //~ ERROR Public: pub(crate), Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-            #[rustc_effective_visibility]
-            A( //~ ERROR Public: pub(crate), Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-                #[rustc_effective_visibility]
-                PubUnion,  //~ ERROR Public: pub(crate), Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-            ),
-        }
-    }
-
-    #[rustc_effective_visibility]
-    macro_rules! none_macro { //~ Public: pub(crate), Exported: pub(crate), Reachable: pub(crate), ReachableFromImplTrait: pub(crate)
-        () => {};
-    }
-
-    #[macro_export]
-    #[rustc_effective_visibility]
-    macro_rules! public_macro { //~ Public: pub, Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-        () => {};
-    }
-
-    #[rustc_effective_visibility]
-    pub struct ReachableStruct { //~ ERROR Public: pub(crate), Exported: pub(crate), Reachable: pub, ReachableFromImplTrait: pub
-        #[rustc_effective_visibility]
-        pub a: u8, //~ ERROR Public: pub(crate), Exported: pub(crate), Reachable: pub, ReachableFromImplTrait: pub
-    }
-}
-
-#[rustc_effective_visibility]
-pub use outer::inner1; //~ ERROR Public: pub, Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-
-pub fn foo() -> outer::ReachableStruct { outer::ReachableStruct {a: 0} }
-
-mod half_public_import {
-    #[rustc_effective_visibility]
-    pub type HalfPublicImport = u8; //~ ERROR Public: pub(crate), Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-    #[rustc_effective_visibility]
-    #[allow(non_upper_case_globals)]
-    pub(crate) const HalfPublicImport: u8 = 0; //~ ERROR Public: pub(crate), Exported: pub(crate), Reachable: pub(crate), ReachableFromImplTrait: pub(crate)
-}
-
-#[rustc_effective_visibility]
-pub use half_public_import::HalfPublicImport; //~ ERROR Public: pub, Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-                                              //~^ ERROR Public: pub, Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-
-fn main() {}
diff --git a/src/test/ui/privacy/access_levels.stderr b/src/test/ui/privacy/access_levels.stderr
deleted file mode 100644
index 111e02bc329c..000000000000
--- a/src/test/ui/privacy/access_levels.stderr
+++ /dev/null
@@ -1,134 +0,0 @@
-error: Public: pub(crate), Exported: pub(crate), Reachable: pub(crate), ReachableFromImplTrait: pub(crate)
-  --> $DIR/access_levels.rs:4:1
-   |
-LL | mod outer {
-   | ^^^^^^^^^
-
-error: Public: pub(crate), Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-  --> $DIR/access_levels.rs:6:5
-   |
-LL |     pub mod inner1 {
-   |     ^^^^^^^^^^^^^^
-
-error: Public: pub(crate), Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-  --> $DIR/access_levels.rs:9:9
-   |
-LL |         extern "C" {}
-   |         ^^^^^^^^^^^^^
-
-error: Public: pub(crate), Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-  --> $DIR/access_levels.rs:12:9
-   |
-LL |         pub trait PubTrait {
-   |         ^^^^^^^^^^^^^^^^^^
-
-error: Public: pub(self), Exported: pub(self), Reachable: pub(self), ReachableFromImplTrait: pub(self)
-  --> $DIR/access_levels.rs:20:9
-   |
-LL |         struct PrivStruct;
-   |         ^^^^^^^^^^^^^^^^^
-
-error: Public: pub(crate), Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-  --> $DIR/access_levels.rs:23:9
-   |
-LL |         pub union PubUnion {
-   |         ^^^^^^^^^^^^^^^^^^
-
-error: Public: pub(self), Exported: pub(self), Reachable: pub(self), ReachableFromImplTrait: pub(self)
-  --> $DIR/access_levels.rs:25:13
-   |
-LL |             a: u8,
-   |             ^^^^^
-
-error: Public: pub(crate), Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-  --> $DIR/access_levels.rs:27:13
-   |
-LL |             pub b: u8,
-   |             ^^^^^^^^^
-
-error: Public: pub(crate), Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-  --> $DIR/access_levels.rs:31:9
-   |
-LL |         pub enum Enum {
-   |         ^^^^^^^^^^^^^
-
-error: Public: pub(crate), Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-  --> $DIR/access_levels.rs:33:13
-   |
-LL |             A(
-   |             ^
-
-error: Public: pub(crate), Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-  --> $DIR/access_levels.rs:35:17
-   |
-LL |                 PubUnion,
-   |                 ^^^^^^^^
-
-error: Public: pub(crate), Exported: pub(crate), Reachable: pub(crate), ReachableFromImplTrait: pub(crate)
-  --> $DIR/access_levels.rs:41:5
-   |
-LL |     macro_rules! none_macro {
-   |     ^^^^^^^^^^^^^^^^^^^^^^^
-
-error: Public: pub, Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-  --> $DIR/access_levels.rs:47:5
-   |
-LL |     macro_rules! public_macro {
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
-
-error: Public: pub(crate), Exported: pub(crate), Reachable: pub, ReachableFromImplTrait: pub
-  --> $DIR/access_levels.rs:52:5
-   |
-LL |     pub struct ReachableStruct {
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-error: Public: pub(crate), Exported: pub(crate), Reachable: pub, ReachableFromImplTrait: pub
-  --> $DIR/access_levels.rs:54:9
-   |
-LL |         pub a: u8,
-   |         ^^^^^^^^^
-
-error: Public: pub, Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-  --> $DIR/access_levels.rs:59:9
-   |
-LL | pub use outer::inner1;
-   |         ^^^^^^^^^^^^^
-
-error: Public: pub(crate), Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-  --> $DIR/access_levels.rs:65:5
-   |
-LL |     pub type HalfPublicImport = u8;
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
-
-error: Public: pub(crate), Exported: pub(crate), Reachable: pub(crate), ReachableFromImplTrait: pub(crate)
-  --> $DIR/access_levels.rs:68:5
-   |
-LL |     pub(crate) const HalfPublicImport: u8 = 0;
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-error: Public: pub, Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-  --> $DIR/access_levels.rs:72:9
-   |
-LL | pub use half_public_import::HalfPublicImport;
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-error: Public: pub, Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-  --> $DIR/access_levels.rs:72:9
-   |
-LL | pub use half_public_import::HalfPublicImport;
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-error: Public: pub(crate), Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-  --> $DIR/access_levels.rs:14:13
-   |
-LL |             const A: i32;
-   |             ^^^^^^^^^^^^
-
-error: Public: pub(crate), Exported: pub, Reachable: pub, ReachableFromImplTrait: pub
-  --> $DIR/access_levels.rs:16:13
-   |
-LL |             type B;
-   |             ^^^^^^
-
-error: aborting due to 22 previous errors
-
diff --git a/src/test/ui/issues/auxiliary/issue-75907.rs b/src/test/ui/privacy/auxiliary/issue-75907.rs
similarity index 100%
rename from src/test/ui/issues/auxiliary/issue-75907.rs
rename to src/test/ui/privacy/auxiliary/issue-75907.rs
diff --git a/src/test/ui/privacy/effective_visibilities.rs b/src/test/ui/privacy/effective_visibilities.rs
new file mode 100644
index 000000000000..4479b0d8f61b
--- /dev/null
+++ b/src/test/ui/privacy/effective_visibilities.rs
@@ -0,0 +1,77 @@
+#![feature(rustc_attrs)]
+
+#[rustc_effective_visibility]
+mod outer { //~ ERROR Direct: pub(crate), Reexported: pub(crate), Reachable: pub(crate), ReachableThroughImplTrait: pub(crate)
+    #[rustc_effective_visibility]
+    pub mod inner1 { //~ ERROR Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+
+        #[rustc_effective_visibility]
+        extern "C" {} //~ ERROR not in the table
+
+        #[rustc_effective_visibility]
+        pub trait PubTrait { //~ ERROR Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+            #[rustc_effective_visibility]
+            const A: i32; //~ ERROR Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+            #[rustc_effective_visibility]
+            type B; //~ ERROR Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+        }
+
+        #[rustc_effective_visibility]
+        struct PrivStruct; //~ ERROR not in the table
+                           //~| ERROR not in the table
+
+        #[rustc_effective_visibility]
+        pub union PubUnion { //~ ERROR Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+            #[rustc_effective_visibility]
+            a: u8, //~ ERROR not in the table
+            #[rustc_effective_visibility]
+            pub b: u8, //~ ERROR Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+        }
+
+        #[rustc_effective_visibility]
+        pub enum Enum { //~ ERROR Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+            #[rustc_effective_visibility]
+            A( //~ ERROR Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+               //~| ERROR Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+                #[rustc_effective_visibility]
+                PubUnion,  //~ ERROR Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+            ),
+        }
+    }
+
+    #[rustc_effective_visibility]
+    macro_rules! none_macro { //~ ERROR not in the table
+        () => {};
+    }
+
+    #[macro_export]
+    #[rustc_effective_visibility]
+    macro_rules! public_macro { //~ ERROR Direct: pub(self), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+        () => {};
+    }
+
+    #[rustc_effective_visibility]
+    pub struct ReachableStruct { //~ ERROR Direct: pub(crate), Reexported: pub(crate), Reachable: pub, ReachableThroughImplTrait: pub
+        #[rustc_effective_visibility]
+        pub a: u8, //~ ERROR Direct: pub(crate), Reexported: pub(crate), Reachable: pub, ReachableThroughImplTrait: pub
+    }
+}
+
+#[rustc_effective_visibility]
+pub use outer::inner1; //~ ERROR Direct: pub, Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+
+pub fn foo() -> outer::ReachableStruct { outer::ReachableStruct {a: 0} }
+
+mod half_public_import {
+    #[rustc_effective_visibility]
+    pub type HalfPublicImport = u8; //~ ERROR Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+    #[rustc_effective_visibility]
+    #[allow(non_upper_case_globals)]
+    pub(crate) const HalfPublicImport: u8 = 0; //~ ERROR Direct: pub(crate), Reexported: pub(crate), Reachable: pub(crate), ReachableThroughImplTrait: pub(crate)
+}
+
+#[rustc_effective_visibility]
+pub use half_public_import::HalfPublicImport; //~ ERROR Direct: pub, Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+                                              //~^ ERROR Direct: pub, Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+
+fn main() {}
diff --git a/src/test/ui/privacy/effective_visibilities.stderr b/src/test/ui/privacy/effective_visibilities.stderr
new file mode 100644
index 000000000000..019aaf8086a6
--- /dev/null
+++ b/src/test/ui/privacy/effective_visibilities.stderr
@@ -0,0 +1,146 @@
+error: Direct: pub(crate), Reexported: pub(crate), Reachable: pub(crate), ReachableThroughImplTrait: pub(crate)
+  --> $DIR/effective_visibilities.rs:4:1
+   |
+LL | mod outer {
+   | ^^^^^^^^^
+
+error: Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+  --> $DIR/effective_visibilities.rs:6:5
+   |
+LL |     pub mod inner1 {
+   |     ^^^^^^^^^^^^^^
+
+error: not in the table
+  --> $DIR/effective_visibilities.rs:9:9
+   |
+LL |         extern "C" {}
+   |         ^^^^^^^^^^^^^
+
+error: Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+  --> $DIR/effective_visibilities.rs:12:9
+   |
+LL |         pub trait PubTrait {
+   |         ^^^^^^^^^^^^^^^^^^
+
+error: not in the table
+  --> $DIR/effective_visibilities.rs:20:9
+   |
+LL |         struct PrivStruct;
+   |         ^^^^^^^^^^^^^^^^^
+
+error: not in the table
+  --> $DIR/effective_visibilities.rs:20:9
+   |
+LL |         struct PrivStruct;
+   |         ^^^^^^^^^^^^^^^^^
+
+error: Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+  --> $DIR/effective_visibilities.rs:24:9
+   |
+LL |         pub union PubUnion {
+   |         ^^^^^^^^^^^^^^^^^^
+
+error: not in the table
+  --> $DIR/effective_visibilities.rs:26:13
+   |
+LL |             a: u8,
+   |             ^^^^^
+
+error: Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+  --> $DIR/effective_visibilities.rs:28:13
+   |
+LL |             pub b: u8,
+   |             ^^^^^^^^^
+
+error: Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+  --> $DIR/effective_visibilities.rs:32:9
+   |
+LL |         pub enum Enum {
+   |         ^^^^^^^^^^^^^
+
+error: Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+  --> $DIR/effective_visibilities.rs:34:13
+   |
+LL |             A(
+   |             ^
+
+error: Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+  --> $DIR/effective_visibilities.rs:34:13
+   |
+LL |             A(
+   |             ^
+
+error: Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+  --> $DIR/effective_visibilities.rs:37:17
+   |
+LL |                 PubUnion,
+   |                 ^^^^^^^^
+
+error: not in the table
+  --> $DIR/effective_visibilities.rs:43:5
+   |
+LL |     macro_rules! none_macro {
+   |     ^^^^^^^^^^^^^^^^^^^^^^^
+
+error: Direct: pub(self), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+  --> $DIR/effective_visibilities.rs:49:5
+   |
+LL |     macro_rules! public_macro {
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: Direct: pub(crate), Reexported: pub(crate), Reachable: pub, ReachableThroughImplTrait: pub
+  --> $DIR/effective_visibilities.rs:54:5
+   |
+LL |     pub struct ReachableStruct {
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: Direct: pub(crate), Reexported: pub(crate), Reachable: pub, ReachableThroughImplTrait: pub
+  --> $DIR/effective_visibilities.rs:56:9
+   |
+LL |         pub a: u8,
+   |         ^^^^^^^^^
+
+error: Direct: pub, Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+  --> $DIR/effective_visibilities.rs:61:9
+   |
+LL | pub use outer::inner1;
+   |         ^^^^^^^^^^^^^
+
+error: Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+  --> $DIR/effective_visibilities.rs:67:5
+   |
+LL |     pub type HalfPublicImport = u8;
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: Direct: pub(crate), Reexported: pub(crate), Reachable: pub(crate), ReachableThroughImplTrait: pub(crate)
+  --> $DIR/effective_visibilities.rs:70:5
+   |
+LL |     pub(crate) const HalfPublicImport: u8 = 0;
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: Direct: pub, Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+  --> $DIR/effective_visibilities.rs:74:9
+   |
+LL | pub use half_public_import::HalfPublicImport;
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: Direct: pub, Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+  --> $DIR/effective_visibilities.rs:74:9
+   |
+LL | pub use half_public_import::HalfPublicImport;
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+  --> $DIR/effective_visibilities.rs:14:13
+   |
+LL |             const A: i32;
+   |             ^^^^^^^^^^^^
+
+error: Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+  --> $DIR/effective_visibilities.rs:16:13
+   |
+LL |             type B;
+   |             ^^^^^^
+
+error: aborting due to 24 previous errors
+
diff --git a/src/test/ui/privacy/effective_visibilities_glob.rs b/src/test/ui/privacy/effective_visibilities_glob.rs
new file mode 100644
index 000000000000..eb9dcd6cd1fa
--- /dev/null
+++ b/src/test/ui/privacy/effective_visibilities_glob.rs
@@ -0,0 +1,21 @@
+// Effective visibility tracking for imports is fine-grained, so `S2` is not fully exported
+// even if its parent import (`m::*`) is fully exported as a `use` item.
+
+#![feature(rustc_attrs)]
+
+mod m {
+    #[rustc_effective_visibility]
+    pub struct S1 {} //~ ERROR Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+    #[rustc_effective_visibility]
+    pub struct S2 {} //~ ERROR Direct: pub(crate), Reexported: pub(crate), Reachable: pub(crate), ReachableThroughImplTrait: pub(crate)
+}
+
+mod glob {
+    #[rustc_effective_visibility]
+    pub use crate::m::*; //~ ERROR Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+}
+
+#[rustc_effective_visibility]
+pub use glob::S1; //~ ERROR Direct: pub, Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+
+fn main() {}
diff --git a/src/test/ui/privacy/effective_visibilities_glob.stderr b/src/test/ui/privacy/effective_visibilities_glob.stderr
new file mode 100644
index 000000000000..0496cd5df8db
--- /dev/null
+++ b/src/test/ui/privacy/effective_visibilities_glob.stderr
@@ -0,0 +1,26 @@
+error: Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+  --> $DIR/effective_visibilities_glob.rs:8:5
+   |
+LL |     pub struct S1 {}
+   |     ^^^^^^^^^^^^^
+
+error: Direct: pub(crate), Reexported: pub(crate), Reachable: pub(crate), ReachableThroughImplTrait: pub(crate)
+  --> $DIR/effective_visibilities_glob.rs:10:5
+   |
+LL |     pub struct S2 {}
+   |     ^^^^^^^^^^^^^
+
+error: Direct: pub(crate), Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+  --> $DIR/effective_visibilities_glob.rs:15:13
+   |
+LL |     pub use crate::m::*;
+   |             ^^^^^^^^
+
+error: Direct: pub, Reexported: pub, Reachable: pub, ReachableThroughImplTrait: pub
+  --> $DIR/effective_visibilities_glob.rs:19:9
+   |
+LL | pub use glob::S1;
+   |         ^^^^^^^^
+
+error: aborting due to 4 previous errors
+
diff --git a/src/test/ui/issues/issue-75907.rs b/src/test/ui/privacy/issue-75907.rs
similarity index 100%
rename from src/test/ui/issues/issue-75907.rs
rename to src/test/ui/privacy/issue-75907.rs
diff --git a/src/test/ui/issues/issue-75907.stderr b/src/test/ui/privacy/issue-75907.stderr
similarity index 100%
rename from src/test/ui/issues/issue-75907.stderr
rename to src/test/ui/privacy/issue-75907.stderr
diff --git a/src/test/ui/issues/issue-75907_b.rs b/src/test/ui/privacy/issue-75907_b.rs
similarity index 100%
rename from src/test/ui/issues/issue-75907_b.rs
rename to src/test/ui/privacy/issue-75907_b.rs
diff --git a/src/test/ui/issues/issue-75907_b.stderr b/src/test/ui/privacy/issue-75907_b.stderr
similarity index 100%
rename from src/test/ui/issues/issue-75907_b.stderr
rename to src/test/ui/privacy/issue-75907_b.stderr
diff --git a/src/test/ui/proc-macro/amputate-span.stderr b/src/test/ui/proc-macro/amputate-span.stderr
index 9553ba3da542..ab4670411446 100644
--- a/src/test/ui/proc-macro/amputate-span.stderr
+++ b/src/test/ui/proc-macro/amputate-span.stderr
@@ -2,7 +2,7 @@ error[E0433]: failed to resolve: use of undeclared type `Command`
   --> $DIR/amputate-span.rs:49:5
    |
 LL |     Command::new("git");
-   |     ^^^^^^^ not found in this scope
+   |     ^^^^^^^ use of undeclared type `Command`
    |
 help: consider importing this struct
    |
@@ -13,7 +13,7 @@ error[E0433]: failed to resolve: use of undeclared type `Command`
   --> $DIR/amputate-span.rs:63:9
    |
 LL |         Command::new("git");
-   |         ^^^^^^^ not found in this scope
+   |         ^^^^^^^ use of undeclared type `Command`
    |
 help: consider importing this struct
    |
diff --git a/src/test/ui/proc-macro/expand-expr.rs b/src/test/ui/proc-macro/expand-expr.rs
index d1146d970306..8d51b7e17185 100644
--- a/src/test/ui/proc-macro/expand-expr.rs
+++ b/src/test/ui/proc-macro/expand-expr.rs
@@ -1,5 +1,5 @@
 // aux-build:expand-expr.rs
-
+#![feature(concat_bytes)]
 extern crate expand_expr;
 
 use expand_expr::{
@@ -23,6 +23,11 @@ expand_expr_is!(
     concat!("contents: ", include_str!("auxiliary/included-file.txt"))
 );
 
+expand_expr_is!(
+    b"contents: Included file contents\n",
+    concat_bytes!(b"contents: ", include_bytes!("auxiliary/included-file.txt"))
+);
+
 // Correct value is checked for multiple sources.
 check_expand_expr_file!(file!());
 
diff --git a/src/test/ui/proc-macro/expand-expr.stderr b/src/test/ui/proc-macro/expand-expr.stderr
index 8dc2d0cfc2f8..c6c4695fd9c4 100644
--- a/src/test/ui/proc-macro/expand-expr.stderr
+++ b/src/test/ui/proc-macro/expand-expr.stderr
@@ -1,29 +1,29 @@
 error: expected one of `.`, `?`, or an operator, found `;`
-  --> $DIR/expand-expr.rs:101:27
+  --> $DIR/expand-expr.rs:106:27
    |
 LL | expand_expr_fail!("string"; hello);
    |                           ^ expected one of `.`, `?`, or an operator
 
 error: expected expression, found `$`
-  --> $DIR/expand-expr.rs:104:19
+  --> $DIR/expand-expr.rs:109:19
    |
 LL | expand_expr_fail!($);
    |                   ^ expected expression
 
 error: expected expression, found `$`
-  --> $DIR/expand-expr.rs:33:23
+  --> $DIR/expand-expr.rs:38:23
    |
 LL |     ($($t:tt)*) => { $($t)* };
    |                       ^^^^ expected expression
 
 error: expected expression, found `$`
-  --> $DIR/expand-expr.rs:106:28
+  --> $DIR/expand-expr.rs:111:28
    |
 LL | expand_expr_fail!(echo_pm!($));
    |                            ^ expected expression
 
 error: macro expansion ignores token `hello` and any following
-  --> $DIR/expand-expr.rs:110:47
+  --> $DIR/expand-expr.rs:115:47
    |
 LL | expand_expr_is!("string", echo_tts!("string"; hello));
    |                           --------------------^^^^^-- help: you might be missing a semicolon here: `;`
@@ -33,7 +33,7 @@ LL | expand_expr_is!("string", echo_tts!("string"; hello));
    = note: the usage of `echo_tts!` is likely invalid in expression context
 
 error: macro expansion ignores token `;` and any following
-  --> $DIR/expand-expr.rs:111:44
+  --> $DIR/expand-expr.rs:116:44
    |
 LL | expand_expr_is!("string", echo_pm!("string"; hello));
    |                           -----------------^-------- help: you might be missing a semicolon here: `;`
@@ -43,7 +43,7 @@ LL | expand_expr_is!("string", echo_pm!("string"; hello));
    = note: the usage of `echo_pm!` is likely invalid in expression context
 
 error: recursion limit reached while expanding `recursive_expand!`
-  --> $DIR/expand-expr.rs:119:16
+  --> $DIR/expand-expr.rs:124:16
    |
 LL | const _: u32 = recursive_expand!();
    |                ^^^^^^^^^^^^^^^^^^^
diff --git a/src/test/ui/proc-macro/generate-mod.rs b/src/test/ui/proc-macro/generate-mod.rs
index 471f317edf96..9eea630c310e 100644
--- a/src/test/ui/proc-macro/generate-mod.rs
+++ b/src/test/ui/proc-macro/generate-mod.rs
@@ -15,19 +15,16 @@ struct S;
 
 #[derive(generate_mod::CheckDerive)] //~ ERROR cannot find type `FromOutside` in this scope
                                      //~| ERROR cannot find type `OuterDerive` in this scope
-                                     //~| WARN this was previously accepted
-                                     //~| WARN this was previously accepted
 struct Z;
 
 fn inner_block() {
     #[derive(generate_mod::CheckDerive)] //~ ERROR cannot find type `FromOutside` in this scope
                                         //~| ERROR cannot find type `OuterDerive` in this scope
-                                        //~| WARN this was previously accepted
-                                        //~| WARN this was previously accepted
     struct InnerZ;
 }
 
-#[derive(generate_mod::CheckDeriveLint)] // OK, lint is suppressed
+#[derive(generate_mod::CheckDeriveLint)] //~  ERROR cannot find type `OuterDeriveLint` in this scope
+                                         //~| ERROR cannot find type `FromOutside` in this scope
 struct W;
 
 fn main() {}
diff --git a/src/test/ui/proc-macro/generate-mod.stderr b/src/test/ui/proc-macro/generate-mod.stderr
index 39bf28dba968..64042ca0ecde 100644
--- a/src/test/ui/proc-macro/generate-mod.stderr
+++ b/src/test/ui/proc-macro/generate-mod.stderr
@@ -38,127 +38,66 @@ LL | #[generate_mod::check_attr]
            OuterAttr
    = note: this error originates in the attribute macro `generate_mod::check_attr` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: cannot find type `FromOutside` in this scope
+error[E0412]: cannot find type `FromOutside` in this scope
   --> $DIR/generate-mod.rs:16:10
    |
 LL | #[derive(generate_mod::CheckDerive)]
-   |          ^^^^^^^^^^^^^^^^^^^^^^^^^ names from parent modules are not accessible without an explicit import
+   |          ^^^^^^^^^^^^^^^^^^^^^^^^^ not found in this scope
    |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #83583 <https://github.com/rust-lang/rust/issues/83583>
-   = note: `#[deny(proc_macro_derive_resolution_fallback)]` on by default
+   = note: consider importing this struct:
+           FromOutside
    = note: this error originates in the derive macro `generate_mod::CheckDerive` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: cannot find type `OuterDerive` in this scope
+error[E0412]: cannot find type `OuterDerive` in this scope
   --> $DIR/generate-mod.rs:16:10
    |
 LL | #[derive(generate_mod::CheckDerive)]
-   |          ^^^^^^^^^^^^^^^^^^^^^^^^^ names from parent modules are not accessible without an explicit import
+   |          ^^^^^^^^^^^^^^^^^^^^^^^^^ not found in this scope
    |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #83583 <https://github.com/rust-lang/rust/issues/83583>
+   = note: consider importing this struct:
+           OuterDerive
    = note: this error originates in the derive macro `generate_mod::CheckDerive` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: cannot find type `FromOutside` in this scope
-  --> $DIR/generate-mod.rs:23:14
+error[E0412]: cannot find type `FromOutside` in this scope
+  --> $DIR/generate-mod.rs:21:14
    |
 LL |     #[derive(generate_mod::CheckDerive)]
-   |              ^^^^^^^^^^^^^^^^^^^^^^^^^ names from parent modules are not accessible without an explicit import
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^ not found in this scope
    |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #83583 <https://github.com/rust-lang/rust/issues/83583>
+   = note: consider importing this struct:
+           FromOutside
    = note: this error originates in the derive macro `generate_mod::CheckDerive` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: cannot find type `OuterDerive` in this scope
-  --> $DIR/generate-mod.rs:23:14
+error[E0412]: cannot find type `OuterDerive` in this scope
+  --> $DIR/generate-mod.rs:21:14
    |
 LL |     #[derive(generate_mod::CheckDerive)]
-   |              ^^^^^^^^^^^^^^^^^^^^^^^^^ names from parent modules are not accessible without an explicit import
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^ not found in this scope
    |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #83583 <https://github.com/rust-lang/rust/issues/83583>
+   = note: consider importing this struct:
+           OuterDerive
    = note: this error originates in the derive macro `generate_mod::CheckDerive` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: aborting due to 8 previous errors
+error[E0412]: cannot find type `FromOutside` in this scope
+  --> $DIR/generate-mod.rs:26:10
+   |
+LL | #[derive(generate_mod::CheckDeriveLint)]
+   |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not found in this scope
+   |
+   = note: consider importing this struct:
+           FromOutside
+   = note: this error originates in the derive macro `generate_mod::CheckDeriveLint` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error[E0412]: cannot find type `OuterDeriveLint` in this scope
+  --> $DIR/generate-mod.rs:26:10
+   |
+LL | #[derive(generate_mod::CheckDeriveLint)]
+   |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not found in this scope
+   |
+   = note: consider importing this struct:
+           OuterDeriveLint
+   = note: this error originates in the derive macro `generate_mod::CheckDeriveLint` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error: aborting due to 10 previous errors
 
 For more information about this error, try `rustc --explain E0412`.
-Future incompatibility report: Future breakage diagnostic:
-error: cannot find type `FromOutside` in this scope
-  --> $DIR/generate-mod.rs:16:10
-   |
-LL | #[derive(generate_mod::CheckDerive)]
-   |          ^^^^^^^^^^^^^^^^^^^^^^^^^ names from parent modules are not accessible without an explicit import
-   |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #83583 <https://github.com/rust-lang/rust/issues/83583>
-   = note: `#[deny(proc_macro_derive_resolution_fallback)]` on by default
-   = note: this error originates in the derive macro `generate_mod::CheckDerive` (in Nightly builds, run with -Z macro-backtrace for more info)
-
-Future breakage diagnostic:
-error: cannot find type `OuterDerive` in this scope
-  --> $DIR/generate-mod.rs:16:10
-   |
-LL | #[derive(generate_mod::CheckDerive)]
-   |          ^^^^^^^^^^^^^^^^^^^^^^^^^ names from parent modules are not accessible without an explicit import
-   |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #83583 <https://github.com/rust-lang/rust/issues/83583>
-   = note: `#[deny(proc_macro_derive_resolution_fallback)]` on by default
-   = note: this error originates in the derive macro `generate_mod::CheckDerive` (in Nightly builds, run with -Z macro-backtrace for more info)
-
-Future breakage diagnostic:
-error: cannot find type `FromOutside` in this scope
-  --> $DIR/generate-mod.rs:23:14
-   |
-LL |     #[derive(generate_mod::CheckDerive)]
-   |              ^^^^^^^^^^^^^^^^^^^^^^^^^ names from parent modules are not accessible without an explicit import
-   |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #83583 <https://github.com/rust-lang/rust/issues/83583>
-   = note: `#[deny(proc_macro_derive_resolution_fallback)]` on by default
-   = note: this error originates in the derive macro `generate_mod::CheckDerive` (in Nightly builds, run with -Z macro-backtrace for more info)
-
-Future breakage diagnostic:
-error: cannot find type `OuterDerive` in this scope
-  --> $DIR/generate-mod.rs:23:14
-   |
-LL |     #[derive(generate_mod::CheckDerive)]
-   |              ^^^^^^^^^^^^^^^^^^^^^^^^^ names from parent modules are not accessible without an explicit import
-   |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #83583 <https://github.com/rust-lang/rust/issues/83583>
-   = note: `#[deny(proc_macro_derive_resolution_fallback)]` on by default
-   = note: this error originates in the derive macro `generate_mod::CheckDerive` (in Nightly builds, run with -Z macro-backtrace for more info)
-
-Future breakage diagnostic:
-warning: cannot find type `FromOutside` in this scope
-  --> $DIR/generate-mod.rs:30:10
-   |
-LL | #[derive(generate_mod::CheckDeriveLint)] // OK, lint is suppressed
-   |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ names from parent modules are not accessible without an explicit import
-   |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #83583 <https://github.com/rust-lang/rust/issues/83583>
-note: the lint level is defined here
-  --> $DIR/generate-mod.rs:30:10
-   |
-LL | #[derive(generate_mod::CheckDeriveLint)] // OK, lint is suppressed
-   |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   = note: this warning originates in the derive macro `generate_mod::CheckDeriveLint` (in Nightly builds, run with -Z macro-backtrace for more info)
-
-Future breakage diagnostic:
-warning: cannot find type `OuterDeriveLint` in this scope
-  --> $DIR/generate-mod.rs:30:10
-   |
-LL | #[derive(generate_mod::CheckDeriveLint)] // OK, lint is suppressed
-   |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ names from parent modules are not accessible without an explicit import
-   |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #83583 <https://github.com/rust-lang/rust/issues/83583>
-note: the lint level is defined here
-  --> $DIR/generate-mod.rs:30:10
-   |
-LL | #[derive(generate_mod::CheckDeriveLint)] // OK, lint is suppressed
-   |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   = note: this warning originates in the derive macro `generate_mod::CheckDeriveLint` (in Nightly builds, run with -Z macro-backtrace for more info)
-
diff --git a/src/test/ui/proc-macro/issue-73933-procedural-masquerade.rs b/src/test/ui/proc-macro/issue-73933-procedural-masquerade.rs
index 0c1c51c01a88..a573c6e1c0b8 100644
--- a/src/test/ui/proc-macro/issue-73933-procedural-masquerade.rs
+++ b/src/test/ui/proc-macro/issue-73933-procedural-masquerade.rs
@@ -1,18 +1,11 @@
 // aux-build:test-macros.rs
+// check-pass
 
 #[macro_use]
 extern crate test_macros;
 
 #[derive(Print)]
 enum ProceduralMasqueradeDummyType {
-//~^ ERROR using
-//~| WARN this was previously
-//~| ERROR using
-//~| WARN this was previously
-//~| ERROR using
-//~| WARN this was previously
-//~| ERROR using
-//~| WARN this was previously
     Input
 }
 
diff --git a/src/test/ui/proc-macro/issue-73933-procedural-masquerade.stderr b/src/test/ui/proc-macro/issue-73933-procedural-masquerade.stderr
deleted file mode 100644
index ebb8e825e6a3..000000000000
--- a/src/test/ui/proc-macro/issue-73933-procedural-masquerade.stderr
+++ /dev/null
@@ -1,91 +0,0 @@
-error: using `procedural-masquerade` crate
-  --> $DIR/issue-73933-procedural-masquerade.rs:7:6
-   |
-LL | enum ProceduralMasqueradeDummyType {
-   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
-   = note: The `procedural-masquerade` crate has been unnecessary since Rust 1.30.0. Versions of this crate below 0.1.7 will eventually stop compiling.
-   = note: `#[deny(proc_macro_back_compat)]` on by default
-
-error: using `procedural-masquerade` crate
-  --> $DIR/issue-73933-procedural-masquerade.rs:7:6
-   |
-LL | enum ProceduralMasqueradeDummyType {
-   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
-   = note: The `procedural-masquerade` crate has been unnecessary since Rust 1.30.0. Versions of this crate below 0.1.7 will eventually stop compiling.
-
-error: using `procedural-masquerade` crate
-  --> $DIR/issue-73933-procedural-masquerade.rs:7:6
-   |
-LL | enum ProceduralMasqueradeDummyType {
-   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
-   = note: The `procedural-masquerade` crate has been unnecessary since Rust 1.30.0. Versions of this crate below 0.1.7 will eventually stop compiling.
-
-error: using `procedural-masquerade` crate
-  --> $DIR/issue-73933-procedural-masquerade.rs:7:6
-   |
-LL | enum ProceduralMasqueradeDummyType {
-   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
-   = note: The `procedural-masquerade` crate has been unnecessary since Rust 1.30.0. Versions of this crate below 0.1.7 will eventually stop compiling.
-
-error: aborting due to 4 previous errors
-
-Future incompatibility report: Future breakage diagnostic:
-error: using `procedural-masquerade` crate
-  --> $DIR/issue-73933-procedural-masquerade.rs:7:6
-   |
-LL | enum ProceduralMasqueradeDummyType {
-   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
-   = note: The `procedural-masquerade` crate has been unnecessary since Rust 1.30.0. Versions of this crate below 0.1.7 will eventually stop compiling.
-   = note: `#[deny(proc_macro_back_compat)]` on by default
-
-Future breakage diagnostic:
-error: using `procedural-masquerade` crate
-  --> $DIR/issue-73933-procedural-masquerade.rs:7:6
-   |
-LL | enum ProceduralMasqueradeDummyType {
-   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
-   = note: The `procedural-masquerade` crate has been unnecessary since Rust 1.30.0. Versions of this crate below 0.1.7 will eventually stop compiling.
-   = note: `#[deny(proc_macro_back_compat)]` on by default
-
-Future breakage diagnostic:
-error: using `procedural-masquerade` crate
-  --> $DIR/issue-73933-procedural-masquerade.rs:7:6
-   |
-LL | enum ProceduralMasqueradeDummyType {
-   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
-   = note: The `procedural-masquerade` crate has been unnecessary since Rust 1.30.0. Versions of this crate below 0.1.7 will eventually stop compiling.
-   = note: `#[deny(proc_macro_back_compat)]` on by default
-
-Future breakage diagnostic:
-error: using `procedural-masquerade` crate
-  --> $DIR/issue-73933-procedural-masquerade.rs:7:6
-   |
-LL | enum ProceduralMasqueradeDummyType {
-   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
-   = note: The `procedural-masquerade` crate has been unnecessary since Rust 1.30.0. Versions of this crate below 0.1.7 will eventually stop compiling.
-   = note: `#[deny(proc_macro_back_compat)]` on by default
-
diff --git a/src/test/ui/proc-macro/issue-73933-procedural-masquerade.stdout b/src/test/ui/proc-macro/issue-73933-procedural-masquerade.stdout
index 50334589d0bb..8cd981e03f11 100644
--- a/src/test/ui/proc-macro/issue-73933-procedural-masquerade.stdout
+++ b/src/test/ui/proc-macro/issue-73933-procedural-masquerade.stdout
@@ -1,22 +1,21 @@
-PRINT-DERIVE INPUT (DISPLAY): enum ProceduralMasqueradeDummyType { Input, }
-PRINT-DERIVE RE-COLLECTED (DISPLAY): enum ProceduralMasqueradeDummyType { Input }
+PRINT-DERIVE INPUT (DISPLAY): enum ProceduralMasqueradeDummyType { Input }
 PRINT-DERIVE INPUT (DEBUG): TokenStream [
     Ident {
         ident: "enum",
-        span: #0 bytes(86..90),
+        span: #0 bytes(100..104),
     },
     Ident {
         ident: "ProceduralMasqueradeDummyType",
-        span: #0 bytes(91..120),
+        span: #0 bytes(105..134),
     },
     Group {
         delimiter: Brace,
         stream: TokenStream [
             Ident {
                 ident: "Input",
-                span: #0 bytes(315..320),
+                span: #0 bytes(141..146),
             },
         ],
-        span: #0 bytes(121..322),
+        span: #0 bytes(135..148),
     },
 ]
diff --git a/src/test/ui/proc-macro/pretty-print-hack-hide.rs b/src/test/ui/proc-macro/pretty-print-hack-hide.rs
new file mode 100644
index 000000000000..f53e8fe8252f
--- /dev/null
+++ b/src/test/ui/proc-macro/pretty-print-hack-hide.rs
@@ -0,0 +1,12 @@
+// aux-build:test-macros.rs
+// compile-flags: -Z span-debug
+// check-pass
+
+#![no_std] // Don't load unnecessary hygiene information from std
+extern crate std;
+
+#[macro_use] extern crate test_macros;
+
+include!("pretty-print-hack/rental-0.5.6/src/lib.rs");
+
+fn main() {}
diff --git a/src/test/ui/proc-macro/pretty-print-hack-hide.stdout b/src/test/ui/proc-macro/pretty-print-hack-hide.stdout
new file mode 100644
index 000000000000..ea796bb26976
--- /dev/null
+++ b/src/test/ui/proc-macro/pretty-print-hack-hide.stdout
@@ -0,0 +1,21 @@
+PRINT-DERIVE INPUT (DISPLAY): enum ProceduralMasqueradeDummyType { Input }
+PRINT-DERIVE INPUT (DEBUG): TokenStream [
+    Ident {
+        ident: "enum",
+        span: $DIR/pretty-print-hack/rental-0.5.6/src/lib.rs:4:1: 4:5 (#0),
+    },
+    Ident {
+        ident: "ProceduralMasqueradeDummyType",
+        span: $DIR/pretty-print-hack/rental-0.5.6/src/lib.rs:4:6: 4:35 (#0),
+    },
+    Group {
+        delimiter: Brace,
+        stream: TokenStream [
+            Ident {
+                ident: "Input",
+                span: $DIR/pretty-print-hack/rental-0.5.6/src/lib.rs:13:5: 13:10 (#0),
+            },
+        ],
+        span: $DIR/pretty-print-hack/rental-0.5.6/src/lib.rs:4:36: 14:2 (#0),
+    },
+]
diff --git a/src/test/ui/proc-macro/pretty-print-hack-show.rs b/src/test/ui/proc-macro/pretty-print-hack-show.rs
new file mode 100644
index 000000000000..9b1899e49220
--- /dev/null
+++ b/src/test/ui/proc-macro/pretty-print-hack-show.rs
@@ -0,0 +1,17 @@
+// aux-build:test-macros.rs
+// compile-flags: -Z span-debug
+
+#![no_std] // Don't load unnecessary hygiene information from std
+extern crate std;
+
+#[macro_use] extern crate test_macros;
+
+mod first {
+    include!("pretty-print-hack/allsorts-rental-0.5.6/src/lib.rs");
+}
+
+mod second {
+    include!("pretty-print-hack/rental-0.5.5/src/lib.rs");
+}
+
+fn main() {}
diff --git a/src/test/ui/proc-macro/pretty-print-hack-show.stderr b/src/test/ui/proc-macro/pretty-print-hack-show.stderr
new file mode 100644
index 000000000000..873054927c96
--- /dev/null
+++ b/src/test/ui/proc-macro/pretty-print-hack-show.stderr
@@ -0,0 +1,179 @@
+error: using an old version of `rental`
+  --> $DIR/pretty-print-hack/allsorts-rental-0.5.6/src/lib.rs:4:6
+   |
+LL | enum ProceduralMasqueradeDummyType {
+   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
+   = note: older versions of the `rental` crate will stop compiling in future versions of Rust; please update to `rental` v0.5.6, or switch to one of the `rental` alternatives
+   = note: `#[deny(proc_macro_back_compat)]` on by default
+
+error: using an old version of `rental`
+  --> $DIR/pretty-print-hack/allsorts-rental-0.5.6/src/lib.rs:4:6
+   |
+LL | enum ProceduralMasqueradeDummyType {
+   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
+   = note: older versions of the `rental` crate will stop compiling in future versions of Rust; please update to `rental` v0.5.6, or switch to one of the `rental` alternatives
+
+error: using an old version of `rental`
+  --> $DIR/pretty-print-hack/allsorts-rental-0.5.6/src/lib.rs:4:6
+   |
+LL | enum ProceduralMasqueradeDummyType {
+   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
+   = note: older versions of the `rental` crate will stop compiling in future versions of Rust; please update to `rental` v0.5.6, or switch to one of the `rental` alternatives
+
+error: using an old version of `rental`
+  --> $DIR/pretty-print-hack/allsorts-rental-0.5.6/src/lib.rs:4:6
+   |
+LL | enum ProceduralMasqueradeDummyType {
+   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
+   = note: older versions of the `rental` crate will stop compiling in future versions of Rust; please update to `rental` v0.5.6, or switch to one of the `rental` alternatives
+
+error: using an old version of `rental`
+  --> $DIR/pretty-print-hack/rental-0.5.5/src/lib.rs:4:6
+   |
+LL | enum ProceduralMasqueradeDummyType {
+   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
+   = note: older versions of the `rental` crate will stop compiling in future versions of Rust; please update to `rental` v0.5.6, or switch to one of the `rental` alternatives
+
+error: using an old version of `rental`
+  --> $DIR/pretty-print-hack/rental-0.5.5/src/lib.rs:4:6
+   |
+LL | enum ProceduralMasqueradeDummyType {
+   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
+   = note: older versions of the `rental` crate will stop compiling in future versions of Rust; please update to `rental` v0.5.6, or switch to one of the `rental` alternatives
+
+error: using an old version of `rental`
+  --> $DIR/pretty-print-hack/rental-0.5.5/src/lib.rs:4:6
+   |
+LL | enum ProceduralMasqueradeDummyType {
+   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
+   = note: older versions of the `rental` crate will stop compiling in future versions of Rust; please update to `rental` v0.5.6, or switch to one of the `rental` alternatives
+
+error: using an old version of `rental`
+  --> $DIR/pretty-print-hack/rental-0.5.5/src/lib.rs:4:6
+   |
+LL | enum ProceduralMasqueradeDummyType {
+   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
+   = note: older versions of the `rental` crate will stop compiling in future versions of Rust; please update to `rental` v0.5.6, or switch to one of the `rental` alternatives
+
+error: aborting due to 8 previous errors
+
+Future incompatibility report: Future breakage diagnostic:
+error: using an old version of `rental`
+  --> $DIR/pretty-print-hack/allsorts-rental-0.5.6/src/lib.rs:4:6
+   |
+LL | enum ProceduralMasqueradeDummyType {
+   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
+   = note: older versions of the `rental` crate will stop compiling in future versions of Rust; please update to `rental` v0.5.6, or switch to one of the `rental` alternatives
+   = note: `#[deny(proc_macro_back_compat)]` on by default
+
+Future breakage diagnostic:
+error: using an old version of `rental`
+  --> $DIR/pretty-print-hack/allsorts-rental-0.5.6/src/lib.rs:4:6
+   |
+LL | enum ProceduralMasqueradeDummyType {
+   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
+   = note: older versions of the `rental` crate will stop compiling in future versions of Rust; please update to `rental` v0.5.6, or switch to one of the `rental` alternatives
+   = note: `#[deny(proc_macro_back_compat)]` on by default
+
+Future breakage diagnostic:
+error: using an old version of `rental`
+  --> $DIR/pretty-print-hack/allsorts-rental-0.5.6/src/lib.rs:4:6
+   |
+LL | enum ProceduralMasqueradeDummyType {
+   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
+   = note: older versions of the `rental` crate will stop compiling in future versions of Rust; please update to `rental` v0.5.6, or switch to one of the `rental` alternatives
+   = note: `#[deny(proc_macro_back_compat)]` on by default
+
+Future breakage diagnostic:
+error: using an old version of `rental`
+  --> $DIR/pretty-print-hack/allsorts-rental-0.5.6/src/lib.rs:4:6
+   |
+LL | enum ProceduralMasqueradeDummyType {
+   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
+   = note: older versions of the `rental` crate will stop compiling in future versions of Rust; please update to `rental` v0.5.6, or switch to one of the `rental` alternatives
+   = note: `#[deny(proc_macro_back_compat)]` on by default
+
+Future breakage diagnostic:
+error: using an old version of `rental`
+  --> $DIR/pretty-print-hack/rental-0.5.5/src/lib.rs:4:6
+   |
+LL | enum ProceduralMasqueradeDummyType {
+   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
+   = note: older versions of the `rental` crate will stop compiling in future versions of Rust; please update to `rental` v0.5.6, or switch to one of the `rental` alternatives
+   = note: `#[deny(proc_macro_back_compat)]` on by default
+
+Future breakage diagnostic:
+error: using an old version of `rental`
+  --> $DIR/pretty-print-hack/rental-0.5.5/src/lib.rs:4:6
+   |
+LL | enum ProceduralMasqueradeDummyType {
+   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
+   = note: older versions of the `rental` crate will stop compiling in future versions of Rust; please update to `rental` v0.5.6, or switch to one of the `rental` alternatives
+   = note: `#[deny(proc_macro_back_compat)]` on by default
+
+Future breakage diagnostic:
+error: using an old version of `rental`
+  --> $DIR/pretty-print-hack/rental-0.5.5/src/lib.rs:4:6
+   |
+LL | enum ProceduralMasqueradeDummyType {
+   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
+   = note: older versions of the `rental` crate will stop compiling in future versions of Rust; please update to `rental` v0.5.6, or switch to one of the `rental` alternatives
+   = note: `#[deny(proc_macro_back_compat)]` on by default
+
+Future breakage diagnostic:
+error: using an old version of `rental`
+  --> $DIR/pretty-print-hack/rental-0.5.5/src/lib.rs:4:6
+   |
+LL | enum ProceduralMasqueradeDummyType {
+   |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #83125 <https://github.com/rust-lang/rust/issues/83125>
+   = note: older versions of the `rental` crate will stop compiling in future versions of Rust; please update to `rental` v0.5.6, or switch to one of the `rental` alternatives
+   = note: `#[deny(proc_macro_back_compat)]` on by default
+
diff --git a/src/test/ui/proc-macro/pretty-print-hack-show.stdout b/src/test/ui/proc-macro/pretty-print-hack-show.stdout
new file mode 100644
index 000000000000..3d793d2a0145
--- /dev/null
+++ b/src/test/ui/proc-macro/pretty-print-hack-show.stdout
@@ -0,0 +1,44 @@
+PRINT-DERIVE INPUT (DISPLAY): enum ProceduralMasqueradeDummyType { Input, }
+PRINT-DERIVE RE-COLLECTED (DISPLAY): enum ProceduralMasqueradeDummyType { Input }
+PRINT-DERIVE INPUT (DEBUG): TokenStream [
+    Ident {
+        ident: "enum",
+        span: $DIR/pretty-print-hack/allsorts-rental-0.5.6/src/lib.rs:4:1: 4:5 (#0),
+    },
+    Ident {
+        ident: "ProceduralMasqueradeDummyType",
+        span: $DIR/pretty-print-hack/allsorts-rental-0.5.6/src/lib.rs:4:6: 4:35 (#0),
+    },
+    Group {
+        delimiter: Brace,
+        stream: TokenStream [
+            Ident {
+                ident: "Input",
+                span: $DIR/pretty-print-hack/allsorts-rental-0.5.6/src/lib.rs:13:5: 13:10 (#0),
+            },
+        ],
+        span: $DIR/pretty-print-hack/allsorts-rental-0.5.6/src/lib.rs:4:36: 14:2 (#0),
+    },
+]
+PRINT-DERIVE INPUT (DISPLAY): enum ProceduralMasqueradeDummyType { Input, }
+PRINT-DERIVE RE-COLLECTED (DISPLAY): enum ProceduralMasqueradeDummyType { Input }
+PRINT-DERIVE INPUT (DEBUG): TokenStream [
+    Ident {
+        ident: "enum",
+        span: $DIR/pretty-print-hack/rental-0.5.5/src/lib.rs:4:1: 4:5 (#0),
+    },
+    Ident {
+        ident: "ProceduralMasqueradeDummyType",
+        span: $DIR/pretty-print-hack/rental-0.5.5/src/lib.rs:4:6: 4:35 (#0),
+    },
+    Group {
+        delimiter: Brace,
+        stream: TokenStream [
+            Ident {
+                ident: "Input",
+                span: $DIR/pretty-print-hack/rental-0.5.5/src/lib.rs:13:5: 13:10 (#0),
+            },
+        ],
+        span: $DIR/pretty-print-hack/rental-0.5.5/src/lib.rs:4:36: 14:2 (#0),
+    },
+]
diff --git a/src/test/ui/proc-macro/pretty-print-hack/allsorts-rental-0.5.6/src/lib.rs b/src/test/ui/proc-macro/pretty-print-hack/allsorts-rental-0.5.6/src/lib.rs
new file mode 100644
index 000000000000..9501980fa55d
--- /dev/null
+++ b/src/test/ui/proc-macro/pretty-print-hack/allsorts-rental-0.5.6/src/lib.rs
@@ -0,0 +1,14 @@
+// ignore-test
+
+#[derive(Print)]
+enum ProceduralMasqueradeDummyType {
+//~^ ERROR using
+//~| WARN this was previously
+//~| ERROR using
+//~| WARN this was previously
+//~| ERROR using
+//~| WARN this was previously
+//~| ERROR using
+//~| WARN this was previously
+    Input
+}
diff --git a/src/test/ui/proc-macro/pretty-print-hack/rental-0.5.5/src/lib.rs b/src/test/ui/proc-macro/pretty-print-hack/rental-0.5.5/src/lib.rs
new file mode 100644
index 000000000000..9501980fa55d
--- /dev/null
+++ b/src/test/ui/proc-macro/pretty-print-hack/rental-0.5.5/src/lib.rs
@@ -0,0 +1,14 @@
+// ignore-test
+
+#[derive(Print)]
+enum ProceduralMasqueradeDummyType {
+//~^ ERROR using
+//~| WARN this was previously
+//~| ERROR using
+//~| WARN this was previously
+//~| ERROR using
+//~| WARN this was previously
+//~| ERROR using
+//~| WARN this was previously
+    Input
+}
diff --git a/src/test/ui/proc-macro/pretty-print-hack/rental-0.5.6/src/lib.rs b/src/test/ui/proc-macro/pretty-print-hack/rental-0.5.6/src/lib.rs
new file mode 100644
index 000000000000..9501980fa55d
--- /dev/null
+++ b/src/test/ui/proc-macro/pretty-print-hack/rental-0.5.6/src/lib.rs
@@ -0,0 +1,14 @@
+// ignore-test
+
+#[derive(Print)]
+enum ProceduralMasqueradeDummyType {
+//~^ ERROR using
+//~| WARN this was previously
+//~| ERROR using
+//~| WARN this was previously
+//~| ERROR using
+//~| WARN this was previously
+//~| ERROR using
+//~| WARN this was previously
+    Input
+}
diff --git a/src/test/ui/issues/issue-11612.rs b/src/test/ui/regions/issue-11612.rs
similarity index 100%
rename from src/test/ui/issues/issue-11612.rs
rename to src/test/ui/regions/issue-11612.rs
diff --git a/src/test/ui/regions/regions-free-region-ordering-caller1.stderr b/src/test/ui/regions/regions-free-region-ordering-caller1.stderr
index 8042b1740b14..8ef7e22536bf 100644
--- a/src/test/ui/regions/regions-free-region-ordering-caller1.stderr
+++ b/src/test/ui/regions/regions-free-region-ordering-caller1.stderr
@@ -5,7 +5,7 @@ LL | fn call1<'a>(x: &'a usize) {
    |          -- lifetime `'a` defined here
 ...
 LL |     let z: &'a & usize = &(&y);
-   |            -----------    ^^^^ creates a temporary which is freed while still in use
+   |            -----------    ^^^^ creates a temporary value which is freed while still in use
    |            |
    |            type annotation requires that borrow lasts for `'a`
 ...
diff --git a/src/test/ui/regions/regions-var-type-out-of-scope.stderr b/src/test/ui/regions/regions-var-type-out-of-scope.stderr
index 476e82f046f0..c32bbe0ee1fb 100644
--- a/src/test/ui/regions/regions-var-type-out-of-scope.stderr
+++ b/src/test/ui/regions/regions-var-type-out-of-scope.stderr
@@ -4,7 +4,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |         x = &id(3);
    |              ^^^^^- temporary value is freed at the end of this statement
    |              |
-   |              creates a temporary which is freed while still in use
+   |              creates a temporary value which is freed while still in use
 LL |         assert_eq!(*x, 3);
    |         ----------------- borrow later used here
    |
diff --git a/src/test/ui/align-with-extern-c-fn.rs b/src/test/ui/repr/align-with-extern-c-fn.rs
similarity index 100%
rename from src/test/ui/align-with-extern-c-fn.rs
rename to src/test/ui/repr/align-with-extern-c-fn.rs
diff --git a/src/test/ui/aligned_enum_cast.rs b/src/test/ui/repr/aligned_enum_cast.rs
similarity index 100%
rename from src/test/ui/aligned_enum_cast.rs
rename to src/test/ui/repr/aligned_enum_cast.rs
diff --git a/src/test/ui/repr_c_int_align.rs b/src/test/ui/repr/repr_c_int_align.rs
similarity index 100%
rename from src/test/ui/repr_c_int_align.rs
rename to src/test/ui/repr/repr_c_int_align.rs
diff --git a/src/test/ui/resolve/issue-103474.rs b/src/test/ui/resolve/issue-103474.rs
new file mode 100644
index 000000000000..14f2259e1d4e
--- /dev/null
+++ b/src/test/ui/resolve/issue-103474.rs
@@ -0,0 +1,28 @@
+struct S {}
+impl S {
+    fn first(&self) {}
+
+    fn second(&self) {
+        first()
+        //~^ ERROR cannot find function `first` in this scope
+    }
+
+    fn third(&self) {
+        no_method_err()
+        //~^ ERROR cannot find function `no_method_err` in this scope
+    }
+}
+
+// https://github.com/rust-lang/rust/pull/103531#discussion_r1004728080
+struct Foo {
+    i: i32,
+}
+
+impl Foo {
+    fn needs_self() {
+        this.i
+        //~^ ERROR cannot find value `this` in this scope
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/resolve/issue-103474.stderr b/src/test/ui/resolve/issue-103474.stderr
new file mode 100644
index 000000000000..415d231552a0
--- /dev/null
+++ b/src/test/ui/resolve/issue-103474.stderr
@@ -0,0 +1,35 @@
+error[E0425]: cannot find value `this` in this scope
+  --> $DIR/issue-103474.rs:23:9
+   |
+LL |         this.i
+   |         ^^^^ not found in this scope
+   |
+help: you might have meant to use `self` here instead
+   |
+LL |         self.i
+   |         ~~~~
+help: if you meant to use `self`, you are also missing a `self` receiver argument
+   |
+LL |     fn needs_self(&self) {
+   |                   +++++
+
+error[E0425]: cannot find function `first` in this scope
+  --> $DIR/issue-103474.rs:6:9
+   |
+LL |         first()
+   |         ^^^^^ not found in this scope
+   |
+help: consider using the associated function
+   |
+LL |         self.first()
+   |         +++++
+
+error[E0425]: cannot find function `no_method_err` in this scope
+  --> $DIR/issue-103474.rs:11:9
+   |
+LL |         no_method_err()
+   |         ^^^^^^^^^^^^^ not found in this scope
+
+error: aborting due to 3 previous errors
+
+For more information about this error, try `rustc --explain E0425`.
diff --git a/src/test/ui/resolve/issue-14254.stderr b/src/test/ui/resolve/issue-14254.stderr
index c848014ad8f0..690a40f7edd7 100644
--- a/src/test/ui/resolve/issue-14254.stderr
+++ b/src/test/ui/resolve/issue-14254.stderr
@@ -26,7 +26,12 @@ error[E0425]: cannot find value `bah` in this scope
   --> $DIR/issue-14254.rs:36:9
    |
 LL |         bah;
-   |         ^^^ help: you might have meant to call the associated function: `Self::bah`
+   |         ^^^
+   |
+help: you might have meant to refer to the associated function
+   |
+LL |         Self::bah;
+   |         ~~~~~~~~~
 
 error[E0425]: cannot find value `b` in this scope
   --> $DIR/issue-14254.rs:38:9
@@ -56,7 +61,12 @@ error[E0425]: cannot find value `bah` in this scope
   --> $DIR/issue-14254.rs:53:9
    |
 LL |         bah;
-   |         ^^^ help: you might have meant to call the associated function: `Self::bah`
+   |         ^^^
+   |
+help: you might have meant to refer to the associated function
+   |
+LL |         Self::bah;
+   |         ~~~~~~~~~
 
 error[E0425]: cannot find value `b` in this scope
   --> $DIR/issue-14254.rs:55:9
@@ -68,31 +78,56 @@ error[E0425]: cannot find value `bah` in this scope
   --> $DIR/issue-14254.rs:64:9
    |
 LL |         bah;
-   |         ^^^ help: you might have meant to call the associated function: `Self::bah`
+   |         ^^^
+   |
+help: you might have meant to refer to the associated function
+   |
+LL |         Self::bah;
+   |         ~~~~~~~~~
 
 error[E0425]: cannot find value `bah` in this scope
   --> $DIR/issue-14254.rs:73:9
    |
 LL |         bah;
-   |         ^^^ help: you might have meant to call the associated function: `Self::bah`
+   |         ^^^
+   |
+help: you might have meant to refer to the associated function
+   |
+LL |         Self::bah;
+   |         ~~~~~~~~~
 
 error[E0425]: cannot find value `bah` in this scope
   --> $DIR/issue-14254.rs:82:9
    |
 LL |         bah;
-   |         ^^^ help: you might have meant to call the associated function: `Self::bah`
+   |         ^^^
+   |
+help: you might have meant to refer to the associated function
+   |
+LL |         Self::bah;
+   |         ~~~~~~~~~
 
 error[E0425]: cannot find value `bah` in this scope
   --> $DIR/issue-14254.rs:91:9
    |
 LL |         bah;
-   |         ^^^ help: you might have meant to call the associated function: `Self::bah`
+   |         ^^^
+   |
+help: you might have meant to refer to the associated function
+   |
+LL |         Self::bah;
+   |         ~~~~~~~~~
 
 error[E0425]: cannot find value `bah` in this scope
   --> $DIR/issue-14254.rs:100:9
    |
 LL |         bah;
-   |         ^^^ help: you might have meant to call the associated function: `Self::bah`
+   |         ^^^
+   |
+help: you might have meant to refer to the associated function
+   |
+LL |         Self::bah;
+   |         ~~~~~~~~~
 
 error[E0425]: cannot find function `baz` in this scope
   --> $DIR/issue-14254.rs:19:9
diff --git a/src/test/ui/resolve/issue-23305.rs b/src/test/ui/resolve/issue-23305.rs
index 95635e12a63b..6d7fe7c50a23 100644
--- a/src/test/ui/resolve/issue-23305.rs
+++ b/src/test/ui/resolve/issue-23305.rs
@@ -3,6 +3,6 @@ pub trait ToNbt<T> {
 }
 
 impl dyn ToNbt<Self> {}
-//~^ ERROR cycle detected
+//~^ ERROR `Self` is not valid in the self type of an impl block
 
 fn main() {}
diff --git a/src/test/ui/resolve/issue-23305.stderr b/src/test/ui/resolve/issue-23305.stderr
index 20aeb7b995a6..aad1b583a324 100644
--- a/src/test/ui/resolve/issue-23305.stderr
+++ b/src/test/ui/resolve/issue-23305.stderr
@@ -1,22 +1,10 @@
-error[E0391]: cycle detected when computing type of `<impl at $DIR/issue-23305.rs:5:1: 5:21>`
+error: `Self` is not valid in the self type of an impl block
   --> $DIR/issue-23305.rs:5:16
    |
 LL | impl dyn ToNbt<Self> {}
    |                ^^^^
    |
-   = note: ...which immediately requires computing type of `<impl at $DIR/issue-23305.rs:5:1: 5:21>` again
-note: cycle used when collecting item types in top-level module
-  --> $DIR/issue-23305.rs:1:1
-   |
-LL | / pub trait ToNbt<T> {
-LL | |     fn new(val: T) -> Self;
-LL | | }
-LL | |
-...  |
-LL | |
-LL | | fn main() {}
-   | |____________^
+   = note: replace `Self` with a different type
 
 error: aborting due to previous error
 
-For more information about this error, try `rustc --explain E0391`.
diff --git a/src/test/ui/resolve/issue-2356.stderr b/src/test/ui/resolve/issue-2356.stderr
index e7c53ff44e6f..36f3da7c9553 100644
--- a/src/test/ui/resolve/issue-2356.stderr
+++ b/src/test/ui/resolve/issue-2356.stderr
@@ -85,7 +85,7 @@ LL |         static_method();
 help: consider using the associated function
    |
 LL |         Self::static_method();
-   |         ~~~~~~~~~~~~~~~~~~~
+   |         ++++++
 
 error[E0425]: cannot find function `purr` in this scope
   --> $DIR/issue-2356.rs:54:9
@@ -114,7 +114,7 @@ LL |     grow_older();
 help: consider using the associated function
    |
 LL |     Self::grow_older();
-   |     ~~~~~~~~~~~~~~~~
+   |     ++++++
 
 error[E0425]: cannot find function `shave` in this scope
   --> $DIR/issue-2356.rs:74:5
diff --git a/src/test/ui/issues/issue-35675.rs b/src/test/ui/resolve/issue-35675.rs
similarity index 100%
rename from src/test/ui/issues/issue-35675.rs
rename to src/test/ui/resolve/issue-35675.rs
diff --git a/src/test/ui/issues/issue-35675.stderr b/src/test/ui/resolve/issue-35675.stderr
similarity index 100%
rename from src/test/ui/issues/issue-35675.stderr
rename to src/test/ui/resolve/issue-35675.stderr
diff --git a/src/test/ui/issues/issue-5927.rs b/src/test/ui/resolve/issue-5927.rs
similarity index 100%
rename from src/test/ui/issues/issue-5927.rs
rename to src/test/ui/resolve/issue-5927.rs
diff --git a/src/test/ui/issues/issue-5927.stderr b/src/test/ui/resolve/issue-5927.stderr
similarity index 100%
rename from src/test/ui/issues/issue-5927.stderr
rename to src/test/ui/resolve/issue-5927.stderr
diff --git a/src/test/ui/resolve/missing-in-namespace.stderr b/src/test/ui/resolve/missing-in-namespace.stderr
index 3d49b2e5dfcd..fc925ba3b6a8 100644
--- a/src/test/ui/resolve/missing-in-namespace.stderr
+++ b/src/test/ui/resolve/missing-in-namespace.stderr
@@ -1,8 +1,8 @@
 error[E0433]: failed to resolve: could not find `hahmap` in `std`
-  --> $DIR/missing-in-namespace.rs:2:29
+  --> $DIR/missing-in-namespace.rs:2:21
    |
 LL |     let _map = std::hahmap::HashMap::new();
-   |                             ^^^^^^^ not found in `std::hahmap`
+   |                     ^^^^^^ could not find `hahmap` in `std`
    |
 help: consider importing this struct
    |
diff --git a/src/test/ui/resolve/point-at-type-parameter-shadowing-another-type.stderr b/src/test/ui/resolve/point-at-type-parameter-shadowing-another-type.stderr
index eb26cd9cabb8..5790e425c0a2 100644
--- a/src/test/ui/resolve/point-at-type-parameter-shadowing-another-type.stderr
+++ b/src/test/ui/resolve/point-at-type-parameter-shadowing-another-type.stderr
@@ -1,16 +1,14 @@
 error[E0574]: expected struct, variant or union type, found type parameter `Baz`
   --> $DIR/point-at-type-parameter-shadowing-another-type.rs:16:13
    |
-LL | / struct Baz {
-LL | |     num: usize,
-LL | | }
-   | |_- you might have meant to refer to this struct
-LL |
-LL |   impl<Baz> Foo<Baz> for Bar {
-   |        --- found this type parameter
+LL | struct Baz {
+   |        --- you might have meant to refer to this struct
 ...
-LL |               Baz { num } => num,
-   |               ^^^ not a struct, variant or union type
+LL | impl<Baz> Foo<Baz> for Bar {
+   |      --- found this type parameter
+...
+LL |             Baz { num } => num,
+   |             ^^^ not a struct, variant or union type
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/resolve/resolve-assoc-suggestions.stderr b/src/test/ui/resolve/resolve-assoc-suggestions.stderr
index b6acaeb8cc23..8def9aa20253 100644
--- a/src/test/ui/resolve/resolve-assoc-suggestions.stderr
+++ b/src/test/ui/resolve/resolve-assoc-suggestions.stderr
@@ -50,7 +50,7 @@ error[E0425]: cannot find value `method` in this scope
   --> $DIR/resolve-assoc-suggestions.rs:34:9
    |
 LL |         method;
-   |         ^^^^^^ help: you might have meant to call the method: `self.method`
+   |         ^^^^^^ help: you might have meant to refer to the method: `self.method`
 
 error: aborting due to 9 previous errors
 
diff --git a/src/test/ui/resolve/resolve-self-in-impl.rs b/src/test/ui/resolve/resolve-self-in-impl.rs
index 024fdc51ea31..d0872d1b76f2 100644
--- a/src/test/ui/resolve/resolve-self-in-impl.rs
+++ b/src/test/ui/resolve/resolve-self-in-impl.rs
@@ -11,10 +11,11 @@ impl Tr for S where Self: Copy {} // OK
 impl Tr for S where S<Self>: Copy {} // OK
 impl Tr for S where Self::A: Copy {} // OK
 
-impl Tr for Self {} //~ ERROR cycle detected
-impl Tr for S<Self> {} //~ ERROR cycle detected
-impl Self {} //~ ERROR cycle detected
-impl S<Self> {} //~ ERROR cycle detected
+impl Tr for Self {} //~ ERROR `Self` is not valid in the self type of an impl block
+impl Tr for S<Self> {} //~ ERROR `Self` is not valid in the self type of an impl block
+impl Self {} //~ ERROR `Self` is not valid in the self type of an impl block
+impl S<Self> {} //~ ERROR `Self` is not valid in the self type of an impl block
+impl (Self, Self) {} //~ ERROR `Self` is not valid in the self type of an impl block
 impl Tr<Self::A> for S {} //~ ERROR cycle detected
 
 fn main() {}
diff --git a/src/test/ui/resolve/resolve-self-in-impl.stderr b/src/test/ui/resolve/resolve-self-in-impl.stderr
index aa99c1a33352..b3042d413468 100644
--- a/src/test/ui/resolve/resolve-self-in-impl.stderr
+++ b/src/test/ui/resolve/resolve-self-in-impl.stderr
@@ -1,86 +1,50 @@
-error[E0391]: cycle detected when computing type of `<impl at $DIR/resolve-self-in-impl.rs:14:1: 14:17>`
-  --> $DIR/resolve-self-in-impl.rs:14:13
-   |
-LL | impl Tr for Self {}
-   |             ^^^^
-   |
-   = note: ...which immediately requires computing type of `<impl at $DIR/resolve-self-in-impl.rs:14:1: 14:17>` again
-note: cycle used when collecting item types in top-level module
-  --> $DIR/resolve-self-in-impl.rs:1:1
-   |
-LL | / #![feature(associated_type_defaults)]
-LL | |
-LL | | struct S<T = u8>(T);
-LL | | trait Tr<T = u8> {
-...  |
-LL | |
-LL | | fn main() {}
-   | |____________^
-
-error[E0391]: cycle detected when computing type of `<impl at $DIR/resolve-self-in-impl.rs:15:1: 15:20>`
-  --> $DIR/resolve-self-in-impl.rs:15:15
-   |
-LL | impl Tr for S<Self> {}
-   |               ^^^^
-   |
-   = note: ...which immediately requires computing type of `<impl at $DIR/resolve-self-in-impl.rs:15:1: 15:20>` again
-note: cycle used when collecting item types in top-level module
-  --> $DIR/resolve-self-in-impl.rs:1:1
-   |
-LL | / #![feature(associated_type_defaults)]
-LL | |
-LL | | struct S<T = u8>(T);
-LL | | trait Tr<T = u8> {
-...  |
-LL | |
-LL | | fn main() {}
-   | |____________^
-
-error[E0391]: cycle detected when computing type of `<impl at $DIR/resolve-self-in-impl.rs:16:1: 16:10>`
+error: `Self` is not valid in the self type of an impl block
   --> $DIR/resolve-self-in-impl.rs:16:6
    |
 LL | impl Self {}
    |      ^^^^
    |
-   = note: ...which immediately requires computing type of `<impl at $DIR/resolve-self-in-impl.rs:16:1: 16:10>` again
-note: cycle used when collecting item types in top-level module
-  --> $DIR/resolve-self-in-impl.rs:1:1
-   |
-LL | / #![feature(associated_type_defaults)]
-LL | |
-LL | | struct S<T = u8>(T);
-LL | | trait Tr<T = u8> {
-...  |
-LL | |
-LL | | fn main() {}
-   | |____________^
+   = note: replace `Self` with a different type
 
-error[E0391]: cycle detected when computing type of `<impl at $DIR/resolve-self-in-impl.rs:17:1: 17:13>`
+error: `Self` is not valid in the self type of an impl block
   --> $DIR/resolve-self-in-impl.rs:17:8
    |
 LL | impl S<Self> {}
    |        ^^^^
    |
-   = note: ...which immediately requires computing type of `<impl at $DIR/resolve-self-in-impl.rs:17:1: 17:13>` again
-note: cycle used when collecting item types in top-level module
-  --> $DIR/resolve-self-in-impl.rs:1:1
-   |
-LL | / #![feature(associated_type_defaults)]
-LL | |
-LL | | struct S<T = u8>(T);
-LL | | trait Tr<T = u8> {
-...  |
-LL | |
-LL | | fn main() {}
-   | |____________^
+   = note: replace `Self` with a different type
 
-error[E0391]: cycle detected when computing trait implemented by `<impl at $DIR/resolve-self-in-impl.rs:18:1: 18:23>`
-  --> $DIR/resolve-self-in-impl.rs:18:1
+error: `Self` is not valid in the self type of an impl block
+  --> $DIR/resolve-self-in-impl.rs:18:7
+   |
+LL | impl (Self, Self) {}
+   |       ^^^^  ^^^^
+   |
+   = note: replace `Self` with a different type
+
+error: `Self` is not valid in the self type of an impl block
+  --> $DIR/resolve-self-in-impl.rs:14:13
+   |
+LL | impl Tr for Self {}
+   |             ^^^^
+   |
+   = note: replace `Self` with a different type
+
+error: `Self` is not valid in the self type of an impl block
+  --> $DIR/resolve-self-in-impl.rs:15:15
+   |
+LL | impl Tr for S<Self> {}
+   |               ^^^^
+   |
+   = note: replace `Self` with a different type
+
+error[E0391]: cycle detected when computing trait implemented by `<impl at $DIR/resolve-self-in-impl.rs:19:1: 19:23>`
+  --> $DIR/resolve-self-in-impl.rs:19:1
    |
 LL | impl Tr<Self::A> for S {}
    | ^^^^^^^^^^^^^^^^^^^^^^
    |
-   = note: ...which immediately requires computing trait implemented by `<impl at $DIR/resolve-self-in-impl.rs:18:1: 18:23>` again
+   = note: ...which immediately requires computing trait implemented by `<impl at $DIR/resolve-self-in-impl.rs:19:1: 19:23>` again
 note: cycle used when collecting item types in top-level module
   --> $DIR/resolve-self-in-impl.rs:1:1
    |
@@ -93,6 +57,6 @@ LL | |
 LL | | fn main() {}
    | |____________^
 
-error: aborting due to 5 previous errors
+error: aborting due to 6 previous errors
 
 For more information about this error, try `rustc --explain E0391`.
diff --git a/src/test/ui/resolve/typo-suggestion-for-variable-with-name-similar-to-struct-field.stderr b/src/test/ui/resolve/typo-suggestion-for-variable-with-name-similar-to-struct-field.stderr
index 2764e1f81328..f32e0404e46c 100644
--- a/src/test/ui/resolve/typo-suggestion-for-variable-with-name-similar-to-struct-field.stderr
+++ b/src/test/ui/resolve/typo-suggestion-for-variable-with-name-similar-to-struct-field.stderr
@@ -40,7 +40,7 @@ LL |         bah;
 LL | fn ba() {}
    | ------- similarly named function `ba` defined here
    |
-help: you might have meant to call the associated function
+help: you might have meant to refer to the associated function
    |
 LL |         Self::bah;
    |         ~~~~~~~~~
diff --git a/src/test/ui/resolve/typo-suggestion-mistyped-in-path.rs b/src/test/ui/resolve/typo-suggestion-mistyped-in-path.rs
new file mode 100644
index 000000000000..3ce17a14f146
--- /dev/null
+++ b/src/test/ui/resolve/typo-suggestion-mistyped-in-path.rs
@@ -0,0 +1,42 @@
+struct Struct;
+//~^ NOTE function or associated item `fob` not found for this struct
+
+impl Struct {
+    fn foo() { }
+}
+
+mod module {
+    fn foo() { }
+
+    struct Struct;
+
+    impl Struct {
+        fn foo() { }
+    }
+}
+
+trait Trait {
+    fn foo();
+}
+
+fn main() {
+    Struct::fob();
+    //~^ ERROR no function or associated item named `fob` found for struct `Struct` in the current scope
+    //~| NOTE function or associated item not found in `Struct`
+
+    Struc::foo();
+    //~^ ERROR failed to resolve: use of undeclared type `Struc`
+    //~| NOTE use of undeclared type `Struc`
+
+    modul::foo();
+    //~^ ERROR failed to resolve: use of undeclared crate or module `modul`
+    //~| NOTE use of undeclared crate or module `modul`
+
+    module::Struc::foo();
+    //~^ ERROR failed to resolve: could not find `Struc` in `module`
+    //~| NOTE could not find `Struc` in `module`
+
+    Trai::foo();
+    //~^ ERROR failed to resolve: use of undeclared type `Trai`
+    //~| NOTE use of undeclared type `Trai`
+}
diff --git a/src/test/ui/resolve/typo-suggestion-mistyped-in-path.stderr b/src/test/ui/resolve/typo-suggestion-mistyped-in-path.stderr
new file mode 100644
index 000000000000..ff7cf531c06d
--- /dev/null
+++ b/src/test/ui/resolve/typo-suggestion-mistyped-in-path.stderr
@@ -0,0 +1,54 @@
+error[E0433]: failed to resolve: use of undeclared type `Struc`
+  --> $DIR/typo-suggestion-mistyped-in-path.rs:27:5
+   |
+LL |     Struc::foo();
+   |     ^^^^^
+   |     |
+   |     use of undeclared type `Struc`
+   |     help: a struct with a similar name exists: `Struct`
+
+error[E0433]: failed to resolve: use of undeclared crate or module `modul`
+  --> $DIR/typo-suggestion-mistyped-in-path.rs:31:5
+   |
+LL |     modul::foo();
+   |     ^^^^^ use of undeclared crate or module `modul`
+   |
+help: there is a crate or module with a similar name
+   |
+LL |     module::foo();
+   |     ~~~~~~
+
+error[E0433]: failed to resolve: could not find `Struc` in `module`
+  --> $DIR/typo-suggestion-mistyped-in-path.rs:35:13
+   |
+LL |     module::Struc::foo();
+   |             ^^^^^
+   |             |
+   |             could not find `Struc` in `module`
+   |             help: a struct with a similar name exists: `Struct`
+
+error[E0433]: failed to resolve: use of undeclared type `Trai`
+  --> $DIR/typo-suggestion-mistyped-in-path.rs:39:5
+   |
+LL |     Trai::foo();
+   |     ^^^^
+   |     |
+   |     use of undeclared type `Trai`
+   |     help: a trait with a similar name exists: `Trait`
+
+error[E0599]: no function or associated item named `fob` found for struct `Struct` in the current scope
+  --> $DIR/typo-suggestion-mistyped-in-path.rs:23:13
+   |
+LL | struct Struct;
+   | ------------- function or associated item `fob` not found for this struct
+...
+LL |     Struct::fob();
+   |             ^^^
+   |             |
+   |             function or associated item not found in `Struct`
+   |             help: there is an associated function with a similar name: `foo`
+
+error: aborting due to 5 previous errors
+
+Some errors have detailed explanations: E0433, E0599.
+For more information about an error, try `rustc --explain E0433`.
diff --git a/src/test/ui/resolve/use_suggestion.stderr b/src/test/ui/resolve/use_suggestion.stderr
index 4fff179b1fec..58cb659e8220 100644
--- a/src/test/ui/resolve/use_suggestion.stderr
+++ b/src/test/ui/resolve/use_suggestion.stderr
@@ -8,7 +8,7 @@ error[E0433]: failed to resolve: use of undeclared type `HashMap`
   --> $DIR/use_suggestion.rs:2:14
    |
 LL |     let x1 = HashMap::new();
-   |              ^^^^^^^ not found in this scope
+   |              ^^^^^^^ use of undeclared type `HashMap`
    |
 help: consider importing this struct
    |
diff --git a/src/test/ui/rfc-1937-termination-trait/termination-trait-test-wrong-type.stderr b/src/test/ui/rfc-1937-termination-trait/termination-trait-test-wrong-type.stderr
index 6ee32314607a..9577952119ad 100644
--- a/src/test/ui/rfc-1937-termination-trait/termination-trait-test-wrong-type.stderr
+++ b/src/test/ui/rfc-1937-termination-trait/termination-trait-test-wrong-type.stderr
@@ -1,12 +1,10 @@
 error[E0277]: the trait bound `f32: Termination` is not satisfied
-  --> $DIR/termination-trait-test-wrong-type.rs:6:1
+  --> $DIR/termination-trait-test-wrong-type.rs:6:31
    |
-LL |   #[test]
-   |   ------- in this procedural macro expansion
-LL | / fn can_parse_zero_as_f32() -> Result<f32, ParseFloatError> {
-LL | |     "0".parse()
-LL | | }
-   | |_^ the trait `Termination` is not implemented for `f32`
+LL | #[test]
+   | ------- in this procedural macro expansion
+LL | fn can_parse_zero_as_f32() -> Result<f32, ParseFloatError> {
+   |                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Termination` is not implemented for `f32`
    |
    = note: required for `Result<f32, ParseFloatError>` to implement `Termination`
 note: required by a bound in `assert_test_result`
diff --git a/src/test/ui/rfc-2294-if-let-guard/feature-gate.stderr b/src/test/ui/rfc-2294-if-let-guard/feature-gate.stderr
index e017d04a5c93..96fe11911b7a 100644
--- a/src/test/ui/rfc-2294-if-let-guard/feature-gate.stderr
+++ b/src/test/ui/rfc-2294-if-let-guard/feature-gate.stderr
@@ -72,6 +72,12 @@ LL |     macro_rules! use_expr {
 ...
 LL |     use_expr!(let 0 = 1);
    |               ^^^ no rules expected this token in macro call
+   |
+note: while trying to match meta-variable `$e:expr`
+  --> $DIR/feature-gate.rs:61:10
+   |
+LL |         ($e:expr) => {
+   |          ^^^^^^^
 
 error[E0658]: `if let` guards are experimental
   --> $DIR/feature-gate.rs:7:12
diff --git a/src/test/ui/rfc-2497-if-let-chains/feature-gate.stderr b/src/test/ui/rfc-2497-if-let-chains/feature-gate.stderr
index feea1c254d8d..7a43b71fc8b8 100644
--- a/src/test/ui/rfc-2497-if-let-chains/feature-gate.stderr
+++ b/src/test/ui/rfc-2497-if-let-chains/feature-gate.stderr
@@ -18,6 +18,12 @@ LL |     macro_rules! use_expr {
 ...
 LL |     use_expr!(let 0 = 1);
    |               ^^^ no rules expected this token in macro call
+   |
+note: while trying to match meta-variable `$e:expr`
+  --> $DIR/feature-gate.rs:50:10
+   |
+LL |         ($e:expr) => {
+   |          ^^^^^^^
 
 error[E0658]: `let` expressions in this position are unstable
   --> $DIR/feature-gate.rs:14:16
diff --git a/src/test/ui/rfc-2632-const-trait-impl/const-and-non-const-impl.stderr b/src/test/ui/rfc-2632-const-trait-impl/const-and-non-const-impl.stderr
index f515ec198ada..36a09add4d3b 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/const-and-non-const-impl.stderr
+++ b/src/test/ui/rfc-2632-const-trait-impl/const-and-non-const-impl.stderr
@@ -10,7 +10,7 @@ LL | impl const std::ops::Add for i32 {
    |
    = note: define and implement a trait or new type instead
 
-error[E0119]: conflicting implementations of trait `std::ops::Add` for type `Int`
+error[E0119]: conflicting implementations of trait `Add` for type `Int`
   --> $DIR/const-and-non-const-impl.rs:22:1
    |
 LL | impl std::ops::Add for Int {
diff --git a/src/test/ui/rfc-2632-const-trait-impl/const_derives/derive-const-gate.rs b/src/test/ui/rfc-2632-const-trait-impl/const_derives/derive-const-gate.rs
new file mode 100644
index 000000000000..348ca0ab1906
--- /dev/null
+++ b/src/test/ui/rfc-2632-const-trait-impl/const_derives/derive-const-gate.rs
@@ -0,0 +1,4 @@
+#[derive_const(Default)] //~ ERROR use of unstable library feature
+pub struct S;
+
+fn main() {}
diff --git a/src/test/ui/rfc-2632-const-trait-impl/const_derives/derive-const-gate.stderr b/src/test/ui/rfc-2632-const-trait-impl/const_derives/derive-const-gate.stderr
new file mode 100644
index 000000000000..cc9bdd2715f7
--- /dev/null
+++ b/src/test/ui/rfc-2632-const-trait-impl/const_derives/derive-const-gate.stderr
@@ -0,0 +1,11 @@
+error[E0658]: use of unstable library feature 'derive_const'
+  --> $DIR/derive-const-gate.rs:1:3
+   |
+LL | #[derive_const(Default)]
+   |   ^^^^^^^^^^^^
+   |
+   = help: add `#![feature(derive_const)]` to the crate attributes to enable
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0658`.
diff --git a/src/test/ui/rfc-2632-const-trait-impl/const_derives/derive-const-non-const-type.rs b/src/test/ui/rfc-2632-const-trait-impl/const_derives/derive-const-non-const-type.rs
new file mode 100644
index 000000000000..92843a8a2da4
--- /dev/null
+++ b/src/test/ui/rfc-2632-const-trait-impl/const_derives/derive-const-non-const-type.rs
@@ -0,0 +1,13 @@
+#![feature(derive_const)]
+
+pub struct A;
+
+impl Default for A {
+    fn default() -> A { A }
+}
+
+#[derive_const(Default)]
+pub struct S(A);
+//~^ cannot call non-const fn
+
+fn main() {}
diff --git a/src/test/ui/rfc-2632-const-trait-impl/const_derives/derive-const-non-const-type.stderr b/src/test/ui/rfc-2632-const-trait-impl/const_derives/derive-const-non-const-type.stderr
new file mode 100644
index 000000000000..d463c774e289
--- /dev/null
+++ b/src/test/ui/rfc-2632-const-trait-impl/const_derives/derive-const-non-const-type.stderr
@@ -0,0 +1,14 @@
+error[E0015]: cannot call non-const fn `<A as Default>::default` in constant functions
+  --> $DIR/derive-const-non-const-type.rs:10:14
+   |
+LL | #[derive_const(Default)]
+   |                ------- in this derive macro expansion
+LL | pub struct S(A);
+   |              ^
+   |
+   = note: calls in constant functions are limited to constant functions, tuple structs and tuple variants
+   = note: this error originates in the derive macro `Default` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0015`.
diff --git a/src/test/ui/rfc-2632-const-trait-impl/const_derives/derive-const-use.rs b/src/test/ui/rfc-2632-const-trait-impl/const_derives/derive-const-use.rs
new file mode 100644
index 000000000000..d1fbeac8598e
--- /dev/null
+++ b/src/test/ui/rfc-2632-const-trait-impl/const_derives/derive-const-use.rs
@@ -0,0 +1,19 @@
+// check-pass
+#![feature(const_trait_impl, const_cmp, const_default_impls, derive_const)]
+
+pub struct A;
+
+impl const Default for A {
+    fn default() -> A { A }
+}
+
+impl const PartialEq for A {
+    fn eq(&self, _: &A) -> bool { true }
+}
+
+#[derive_const(Default, PartialEq)]
+pub struct S((), A);
+
+const _: () = assert!(S((), A) == S::default());
+
+fn main() {}
diff --git a/src/test/ui/rfc-2632-const-trait-impl/issue-102985.rs b/src/test/ui/rfc-2632-const-trait-impl/issue-102985.rs
index e0df72003844..07d3f51edce5 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/issue-102985.rs
+++ b/src/test/ui/rfc-2632-const-trait-impl/issue-102985.rs
@@ -4,7 +4,8 @@ struct Bug {
     inner: [(); match || 1 {
         n => n(),
         //~^ ERROR the trait bound
-        //~| ERROR cannot call non-const fn `Bug::inner::{constant#0}::{closure#0}` in constants
+        //~| ERROR the trait bound
+        //~| ERROR cannot call non-const closure in constants
     }],
 }
 
diff --git a/src/test/ui/rfc-2632-const-trait-impl/issue-102985.stderr b/src/test/ui/rfc-2632-const-trait-impl/issue-102985.stderr
index 14d87e7cdc64..b98ccbe5d03e 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/issue-102985.stderr
+++ b/src/test/ui/rfc-2632-const-trait-impl/issue-102985.stderr
@@ -12,15 +12,30 @@ LL |         n => n(),
    |              ^^^
    = note: wrap the `[closure@$DIR/issue-102985.rs:4:23: 4:25]` in a closure with no arguments: `|| { /* code */ }`
 
-error[E0015]: cannot call non-const fn `Bug::inner::{constant#0}::{closure#0}` in constants
+error[E0277]: the trait bound `[closure@$DIR/issue-102985.rs:4:23: 4:25]: ~const Fn<()>` is not satisfied
+  --> $DIR/issue-102985.rs:5:14
+   |
+LL |         n => n(),
+   |              ^^^ expected an `Fn<()>` closure, found `[closure@$DIR/issue-102985.rs:4:23: 4:25]`
+   |
+   = help: the trait `~const Fn<()>` is not implemented for closure `[closure@$DIR/issue-102985.rs:4:23: 4:25]`
+note: the trait `Fn<()>` is implemented for `[closure@$DIR/issue-102985.rs:4:23: 4:25]`, but that implementation is not `const`
+  --> $DIR/issue-102985.rs:5:14
+   |
+LL |         n => n(),
+   |              ^^^
+   = note: wrap the `[closure@$DIR/issue-102985.rs:4:23: 4:25]` in a closure with no arguments: `|| { /* code */ }`
+
+error[E0015]: cannot call non-const closure in constants
   --> $DIR/issue-102985.rs:5:14
    |
 LL |         n => n(),
    |              ^^^
    |
+   = note: closures need an RFC before allowed to be called in constants
    = note: calls in constants are limited to constant functions, tuple structs and tuple variants
 
-error: aborting due to 2 previous errors
+error: aborting due to 3 previous errors
 
 Some errors have detailed explanations: E0015, E0277.
 For more information about an error, try `rustc --explain E0015`.
diff --git a/src/test/ui/rfc-2632-const-trait-impl/issue-103677.rs b/src/test/ui/rfc-2632-const-trait-impl/issue-103677.rs
new file mode 100644
index 000000000000..d81724a3685a
--- /dev/null
+++ b/src/test/ui/rfc-2632-const-trait-impl/issue-103677.rs
@@ -0,0 +1,5 @@
+// check-pass
+
+const _: fn(&String) = |s| { &*s as &str; };
+
+fn main() {}
diff --git a/src/test/ui/rfc-2632-const-trait-impl/specialization/const-default-bound-non-const-specialized-bound.rs b/src/test/ui/rfc-2632-const-trait-impl/specialization/const-default-bound-non-const-specialized-bound.rs
new file mode 100644
index 000000000000..3ac909924864
--- /dev/null
+++ b/src/test/ui/rfc-2632-const-trait-impl/specialization/const-default-bound-non-const-specialized-bound.rs
@@ -0,0 +1,46 @@
+// Tests that trait bounds on specializing trait impls must be `~const` if the
+// same bound is present on the default impl and is `~const` there.
+
+#![feature(const_trait_impl)]
+#![feature(rustc_attrs)]
+#![feature(min_specialization)]
+
+#[rustc_specialization_trait]
+trait Specialize {}
+
+#[const_trait]
+trait Foo {}
+
+#[const_trait]
+trait Bar {}
+
+// bgr360: I was only able to exercise the code path that raises the
+// "missing ~const qualifier" error by making this base impl non-const, even
+// though that doesn't really make sense to do. As seen below, if the base impl
+// is made const, rustc fails earlier with an overlapping impl failure.
+impl<T> Bar for T
+where
+    T: ~const Foo,
+{}
+
+impl<T> Bar for T
+where
+    T: Foo, //~ ERROR missing `~const` qualifier
+    T: Specialize,
+{}
+
+#[const_trait]
+trait Baz {}
+
+impl<T> const Baz for T
+where
+    T: ~const Foo,
+{}
+
+impl<T> const Baz for T //~ ERROR conflicting implementations of trait `Baz`
+where
+    T: Foo,
+    T: Specialize,
+{}
+
+fn main() {}
diff --git a/src/test/ui/rfc-2632-const-trait-impl/specialization/const-default-bound-non-const-specialized-bound.stderr b/src/test/ui/rfc-2632-const-trait-impl/specialization/const-default-bound-non-const-specialized-bound.stderr
new file mode 100644
index 000000000000..4aea1979421c
--- /dev/null
+++ b/src/test/ui/rfc-2632-const-trait-impl/specialization/const-default-bound-non-const-specialized-bound.stderr
@@ -0,0 +1,18 @@
+error: missing `~const` qualifier for specialization
+  --> $DIR/const-default-bound-non-const-specialized-bound.rs:28:8
+   |
+LL |     T: Foo,
+   |        ^^^
+
+error[E0119]: conflicting implementations of trait `Baz`
+  --> $DIR/const-default-bound-non-const-specialized-bound.rs:40:1
+   |
+LL | impl<T> const Baz for T
+   | ----------------------- first implementation here
+...
+LL | impl<T> const Baz for T
+   | ^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0119`.
diff --git a/src/test/ui/rfc-2632-const-trait-impl/specialization/const-default-const-specialized.rs b/src/test/ui/rfc-2632-const-trait-impl/specialization/const-default-const-specialized.rs
new file mode 100644
index 000000000000..9ddea427cfd8
--- /dev/null
+++ b/src/test/ui/rfc-2632-const-trait-impl/specialization/const-default-const-specialized.rs
@@ -0,0 +1,39 @@
+// Tests that a const default trait impl can be specialized by another const
+// trait impl and that the specializing impl will be used during const-eval.
+
+// run-pass
+
+#![feature(const_trait_impl)]
+#![feature(min_specialization)]
+
+#[const_trait]
+trait Value {
+    fn value() -> u32;
+}
+
+const fn get_value<T: ~const Value>() -> u32 {
+    T::value()
+}
+
+impl<T> const Value for T {
+    default fn value() -> u32 {
+        0
+    }
+}
+
+struct FortyTwo;
+
+impl const Value for FortyTwo {
+    fn value() -> u32 {
+        42
+    }
+}
+
+const ZERO: u32 = get_value::<()>();
+
+const FORTY_TWO: u32 = get_value::<FortyTwo>();
+
+fn main() {
+    assert_eq!(ZERO, 0);
+    assert_eq!(FORTY_TWO, 42);
+}
diff --git a/src/test/ui/rfc-2632-const-trait-impl/specialization/const-default-impl-non-const-specialized-impl.rs b/src/test/ui/rfc-2632-const-trait-impl/specialization/const-default-impl-non-const-specialized-impl.rs
new file mode 100644
index 000000000000..a3bb9b3f93ed
--- /dev/null
+++ b/src/test/ui/rfc-2632-const-trait-impl/specialization/const-default-impl-non-const-specialized-impl.rs
@@ -0,0 +1,26 @@
+// Tests that specializing trait impls must be at least as const as the default impl.
+
+#![feature(const_trait_impl)]
+#![feature(min_specialization)]
+
+#[const_trait]
+trait Value {
+    fn value() -> u32;
+}
+
+impl<T> const Value for T {
+    default fn value() -> u32 {
+        0
+    }
+}
+
+struct FortyTwo;
+
+impl Value for FortyTwo { //~ ERROR cannot specialize on const impl with non-const impl
+    fn value() -> u32 {
+        println!("You can't do that (constly)");
+        42
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/rfc-2632-const-trait-impl/specialization/const-default-impl-non-const-specialized-impl.stderr b/src/test/ui/rfc-2632-const-trait-impl/specialization/const-default-impl-non-const-specialized-impl.stderr
new file mode 100644
index 000000000000..24766804708a
--- /dev/null
+++ b/src/test/ui/rfc-2632-const-trait-impl/specialization/const-default-impl-non-const-specialized-impl.stderr
@@ -0,0 +1,8 @@
+error: cannot specialize on const impl with non-const impl
+  --> $DIR/const-default-impl-non-const-specialized-impl.rs:19:1
+   |
+LL | impl Value for FortyTwo {
+   | ^^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to previous error
+
diff --git a/src/test/ui/rfc-2632-const-trait-impl/specialization/default-keyword.rs b/src/test/ui/rfc-2632-const-trait-impl/specialization/default-keyword.rs
new file mode 100644
index 000000000000..2aac0a2b4d11
--- /dev/null
+++ b/src/test/ui/rfc-2632-const-trait-impl/specialization/default-keyword.rs
@@ -0,0 +1,15 @@
+// check-pass
+
+#![feature(const_trait_impl)]
+#![feature(min_specialization)]
+
+#[const_trait]
+trait Foo {
+    fn foo();
+}
+
+impl const Foo for u32 {
+    default fn foo() {}
+}
+
+fn main() {}
diff --git a/src/test/ui/rfc-2632-const-trait-impl/specialization/issue-95186-specialize-on-tilde-const.rs b/src/test/ui/rfc-2632-const-trait-impl/specialization/issue-95186-specialize-on-tilde-const.rs
new file mode 100644
index 000000000000..9c2c2cf1610a
--- /dev/null
+++ b/src/test/ui/rfc-2632-const-trait-impl/specialization/issue-95186-specialize-on-tilde-const.rs
@@ -0,0 +1,37 @@
+// Tests that `~const` trait bounds can be used to specialize const trait impls.
+
+// check-pass
+
+#![feature(const_trait_impl)]
+#![feature(rustc_attrs)]
+#![feature(min_specialization)]
+
+#[const_trait]
+#[rustc_specialization_trait]
+trait Specialize {}
+
+#[const_trait]
+trait Foo {}
+
+impl<T> const Foo for T {}
+
+impl<T> const Foo for T
+where
+    T: ~const Specialize,
+{}
+
+#[const_trait]
+trait Bar {}
+
+impl<T> const Bar for T
+where
+    T: ~const Foo,
+{}
+
+impl<T> const Bar for T
+where
+    T: ~const Foo,
+    T: ~const Specialize,
+{}
+
+fn main() {}
diff --git a/src/test/ui/rfc-2632-const-trait-impl/specialization/issue-95187-same-trait-bound-different-constness.rs b/src/test/ui/rfc-2632-const-trait-impl/specialization/issue-95187-same-trait-bound-different-constness.rs
new file mode 100644
index 000000000000..1e6b1c6513b3
--- /dev/null
+++ b/src/test/ui/rfc-2632-const-trait-impl/specialization/issue-95187-same-trait-bound-different-constness.rs
@@ -0,0 +1,45 @@
+// Tests that `T: ~const Foo` in a specializing impl is treated as equivalent to
+// `T: Foo` in the default impl for the purposes of specialization (i.e., it
+// does not think that the user is attempting to specialize on trait `Foo`).
+
+// check-pass
+
+#![feature(rustc_attrs)]
+#![feature(min_specialization)]
+#![feature(const_trait_impl)]
+
+#[rustc_specialization_trait]
+trait Specialize {}
+
+#[const_trait]
+trait Foo {}
+
+#[const_trait]
+trait Bar {}
+
+impl<T> Bar for T
+where
+    T: Foo,
+{}
+
+impl<T> const Bar for T
+where
+    T: ~const Foo,
+    T: Specialize,
+{}
+
+#[const_trait]
+trait Baz {}
+
+impl<T> const Baz for T
+where
+    T: Foo,
+{}
+
+impl<T> const Baz for T
+where
+    T: ~const Foo,
+    T: Specialize,
+{}
+
+fn main() {}
diff --git a/src/test/ui/rfc-2632-const-trait-impl/specialization/non-const-default-const-specialized.rs b/src/test/ui/rfc-2632-const-trait-impl/specialization/non-const-default-const-specialized.rs
new file mode 100644
index 000000000000..35aa52fbd4ed
--- /dev/null
+++ b/src/test/ui/rfc-2632-const-trait-impl/specialization/non-const-default-const-specialized.rs
@@ -0,0 +1,39 @@
+// Tests that a non-const default impl can be specialized by a const trait impl,
+// but that the default impl cannot be used in a const context.
+
+// run-pass
+
+#![feature(const_trait_impl)]
+#![feature(min_specialization)]
+
+#[const_trait]
+trait Value {
+    fn value() -> u32;
+}
+
+const fn get_value<T: ~const Value>() -> u32 {
+    T::value()
+}
+
+impl<T> Value for T {
+    default fn value() -> u32 {
+        println!("You can't do that (constly)");
+        0
+    }
+}
+
+struct FortyTwo;
+
+impl const Value for FortyTwo {
+    fn value() -> u32 {
+        42
+    }
+}
+
+fn main() {
+    let zero = get_value::<()>();
+    assert_eq!(zero, 0);
+
+    const FORTY_TWO: u32 = get_value::<FortyTwo>();
+    assert_eq!(FORTY_TWO, 42);
+}
diff --git a/src/test/ui/rfc-2632-const-trait-impl/specializing-constness.rs b/src/test/ui/rfc-2632-const-trait-impl/specializing-constness.rs
index ff0cd489d474..9ab170f09200 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/specializing-constness.rs
+++ b/src/test/ui/rfc-2632-const-trait-impl/specializing-constness.rs
@@ -17,7 +17,9 @@ impl<T: ~const Default> const A for T {
     }
 }
 
-impl<T: Default + Sup> A for T { //~ ERROR: cannot specialize
+impl<T: Default + Sup> A for T {
+//~^ ERROR: cannot specialize
+//~| ERROR: missing `~const` qualifier
     fn a() -> u32 {
         3
     }
diff --git a/src/test/ui/rfc-2632-const-trait-impl/specializing-constness.stderr b/src/test/ui/rfc-2632-const-trait-impl/specializing-constness.stderr
index 3296c109c4e7..843fc6ce84d4 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/specializing-constness.stderr
+++ b/src/test/ui/rfc-2632-const-trait-impl/specializing-constness.stderr
@@ -1,8 +1,14 @@
-error: cannot specialize on trait `Default`
+error: cannot specialize on const impl with non-const impl
+  --> $DIR/specializing-constness.rs:20:1
+   |
+LL | impl<T: Default + Sup> A for T {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: missing `~const` qualifier for specialization
   --> $DIR/specializing-constness.rs:20:9
    |
 LL | impl<T: Default + Sup> A for T {
    |         ^^^^^^^
 
-error: aborting due to previous error
+error: aborting due to 2 previous errors
 
diff --git a/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail-2.nn.stderr b/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail-2.nn.stderr
index b86acb2cc9ab..d4f42b787e4d 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail-2.nn.stderr
+++ b/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail-2.nn.stderr
@@ -1,8 +1,8 @@
 error: ~const can only be applied to `#[const_trait]` traits
-  --> $DIR/super-traits-fail-2.rs:11:12
+  --> $DIR/super-traits-fail-2.rs:11:19
    |
 LL | trait Bar: ~const Foo {}
-   |            ^^^^^^^^^^
+   |                   ^^^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail-2.ny.stderr b/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail-2.ny.stderr
index b86acb2cc9ab..d4f42b787e4d 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail-2.ny.stderr
+++ b/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail-2.ny.stderr
@@ -1,8 +1,8 @@
 error: ~const can only be applied to `#[const_trait]` traits
-  --> $DIR/super-traits-fail-2.rs:11:12
+  --> $DIR/super-traits-fail-2.rs:11:19
    |
 LL | trait Bar: ~const Foo {}
-   |            ^^^^^^^^^^
+   |                   ^^^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail-3.nn.stderr b/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail-3.nn.stderr
index 191edca1761c..d433e1cfa698 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail-3.nn.stderr
+++ b/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail-3.nn.stderr
@@ -1,14 +1,14 @@
 error: ~const can only be applied to `#[const_trait]` traits
-  --> $DIR/super-traits-fail-3.rs:12:12
+  --> $DIR/super-traits-fail-3.rs:12:19
    |
 LL | trait Bar: ~const Foo {}
-   |            ^^^^^^^^^^
+   |                   ^^^
 
 error: ~const can only be applied to `#[const_trait]` traits
-  --> $DIR/super-traits-fail-3.rs:15:17
+  --> $DIR/super-traits-fail-3.rs:15:24
    |
 LL | const fn foo<T: ~const Bar>(x: &T) {
-   |                 ^^^^^^^^^^
+   |                        ^^^
 
 error: aborting due to 2 previous errors
 
diff --git a/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail-3.ny.stderr b/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail-3.ny.stderr
index a3b4c302a57f..2a7e8e00bc78 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail-3.ny.stderr
+++ b/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail-3.ny.stderr
@@ -1,8 +1,8 @@
 error: ~const can only be applied to `#[const_trait]` traits
-  --> $DIR/super-traits-fail-3.rs:12:12
+  --> $DIR/super-traits-fail-3.rs:12:19
    |
 LL | trait Bar: ~const Foo {}
-   |            ^^^^^^^^^^
+   |                   ^^^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail-3.yn.stderr b/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail-3.yn.stderr
index 9d6116654659..e5978c12a098 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail-3.yn.stderr
+++ b/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail-3.yn.stderr
@@ -1,8 +1,8 @@
 error: ~const can only be applied to `#[const_trait]` traits
-  --> $DIR/super-traits-fail-3.rs:15:17
+  --> $DIR/super-traits-fail-3.rs:15:24
    |
 LL | const fn foo<T: ~const Bar>(x: &T) {
-   |                 ^^^^^^^^^^
+   |                        ^^^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/rfc1623.rs b/src/test/ui/rfcs/rfc1623-2.rs
similarity index 100%
rename from src/test/ui/rfc1623.rs
rename to src/test/ui/rfcs/rfc1623-2.rs
diff --git a/src/test/ui/rfc1623.stderr b/src/test/ui/rfcs/rfc1623-2.stderr
similarity index 91%
rename from src/test/ui/rfc1623.stderr
rename to src/test/ui/rfcs/rfc1623-2.stderr
index b15a4cb110b7..d183eaaa6236 100644
--- a/src/test/ui/rfc1623.stderr
+++ b/src/test/ui/rfcs/rfc1623-2.stderr
@@ -1,5 +1,5 @@
 error[E0308]: mismatched types
-  --> $DIR/rfc1623.rs:28:8
+  --> $DIR/rfc1623-2.rs:28:8
    |
 LL |     f: &id,
    |        ^^^ one type is more general than the other
@@ -8,7 +8,7 @@ LL |     f: &id,
               found trait `Fn<(&Foo<'_>,)>`
 
 error[E0308]: mismatched types
-  --> $DIR/rfc1623.rs:28:8
+  --> $DIR/rfc1623-2.rs:28:8
    |
 LL |     f: &id,
    |        ^^^ one type is more general than the other
@@ -17,7 +17,7 @@ LL |     f: &id,
               found trait `Fn<(&Foo<'_>,)>`
 
 error: implementation of `FnOnce` is not general enough
-  --> $DIR/rfc1623.rs:28:8
+  --> $DIR/rfc1623-2.rs:28:8
    |
 LL |     f: &id,
    |        ^^^ implementation of `FnOnce` is not general enough
@@ -26,7 +26,7 @@ LL |     f: &id,
    = note: ...but it actually implements `FnOnce<(&'2 Foo<'_>,)>`, for some specific lifetime `'2`
 
 error: implementation of `FnOnce` is not general enough
-  --> $DIR/rfc1623.rs:28:8
+  --> $DIR/rfc1623-2.rs:28:8
    |
 LL |     f: &id,
    |        ^^^ implementation of `FnOnce` is not general enough
diff --git a/src/test/ui/rfc1623-2.rs b/src/test/ui/rfcs/rfc1623-3.rs
similarity index 100%
rename from src/test/ui/rfc1623-2.rs
rename to src/test/ui/rfcs/rfc1623-3.rs
diff --git a/src/test/ui/rfc1623-2.stderr b/src/test/ui/rfcs/rfc1623-3.stderr
similarity index 94%
rename from src/test/ui/rfc1623-2.stderr
rename to src/test/ui/rfcs/rfc1623-3.stderr
index 945c6533c797..77fc3f0412eb 100644
--- a/src/test/ui/rfc1623-2.stderr
+++ b/src/test/ui/rfcs/rfc1623-3.stderr
@@ -1,5 +1,5 @@
 error[E0106]: missing lifetime specifier
-  --> $DIR/rfc1623-2.rs:8:42
+  --> $DIR/rfc1623-3.rs:8:42
    |
 LL | static NON_ELIDABLE_FN: &fn(&u8, &u8) -> &u8 =
    |                             ---  ---     ^ expected named lifetime parameter
@@ -12,7 +12,7 @@ LL | static NON_ELIDABLE_FN: &for<'a> fn(&'a u8, &'a u8) -> &'a u8 =
    |                          +++++++     ++      ++         ++
 
 error[E0106]: missing lifetime specifier
-  --> $DIR/rfc1623-2.rs:10:39
+  --> $DIR/rfc1623-3.rs:10:39
    |
 LL |     &(non_elidable as fn(&u8, &u8) -> &u8);
    |                          ---  ---     ^ expected named lifetime parameter
@@ -24,7 +24,7 @@ LL |     &(non_elidable as for<'a> fn(&'a u8, &'a u8) -> &'a u8);
    |                       +++++++     ++      ++         ++
 
 error[E0605]: non-primitive cast: `for<'a, 'b> fn(&'a u8, &'b u8) -> &'a u8 {non_elidable}` as `for<'a, 'b> fn(&'a u8, &'b u8) -> &u8`
-  --> $DIR/rfc1623-2.rs:10:6
+  --> $DIR/rfc1623-3.rs:10:6
    |
 LL |     &(non_elidable as fn(&u8, &u8) -> &u8);
    |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ invalid cast
diff --git a/src/test/ui/sanitize/memory-passing.rs b/src/test/ui/sanitize/memory-passing.rs
new file mode 100644
index 000000000000..6d9b70ad6b1c
--- /dev/null
+++ b/src/test/ui/sanitize/memory-passing.rs
@@ -0,0 +1,32 @@
+// needs-sanitizer-support
+// needs-sanitizer-memory
+//
+// revisions: unoptimized optimized
+//
+// [optimized]compile-flags: -Z sanitizer=memory -Zsanitizer-memory-track-origins -O
+// [unoptimized]compile-flags: -Z sanitizer=memory -Zsanitizer-memory-track-origins
+//
+// run-pass
+//
+// This test case intentionally limits the usage of the std,
+// since it will be linked with an uninstrumented version of it.
+
+#![feature(core_intrinsics)]
+#![feature(start)]
+#![allow(invalid_value)]
+
+use std::hint::black_box;
+
+fn calling_black_box_on_zst_ok() {
+    // It's OK to call black_box on a value of a zero-sized type, even if its
+    // underlying the memory location is uninitialized. For non-zero-sized types,
+    // this would be an MSAN error.
+    let zst = ();
+    black_box(zst);
+}
+
+#[start]
+fn main(_: isize, _: *const *const u8) -> isize {
+    calling_black_box_on_zst_ok();
+    0
+}
diff --git a/src/test/ui/save-analysis/issue-68621.stderr b/src/test/ui/save-analysis/issue-68621.stderr
index 4a4bf9a6996b..4452ee7915ba 100644
--- a/src/test/ui/save-analysis/issue-68621.stderr
+++ b/src/test/ui/save-analysis/issue-68621.stderr
@@ -4,7 +4,7 @@ error: unconstrained opaque type
 LL |     type Future = impl Trait;
    |                   ^^^^^^^^^^
    |
-   = note: `Future` must be used in combination with a concrete type within the same module
+   = note: `Future` must be used in combination with a concrete type within the same impl
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait-async.stderr b/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait-async.stderr
index 7e7d60d0ff90..eb3d3e4a67a9 100644
--- a/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait-async.stderr
+++ b/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait-async.stderr
@@ -6,7 +6,7 @@ LL |     async fn f(self: Pin<&Self>) -> impl Clone { self }
    |                          |
    |                          hidden type `Pin<&Foo>` captures the anonymous lifetime defined here
    |
-help: to declare that the `impl Trait` captures `'_`, you can add an explicit `'_` lifetime bound
+help: to declare that `impl Clone` captures `'_`, you can add an explicit `'_` lifetime bound
    |
 LL |     async fn f(self: Pin<&Self>) -> impl Clone + '_ { self }
    |                                                ++++
diff --git a/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait.stderr b/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait.stderr
index 30d2250c0c81..2c0b2a0d9193 100644
--- a/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait.stderr
+++ b/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait.stderr
@@ -6,7 +6,7 @@ LL |     fn f(self: Pin<&Self>) -> impl Clone { self }
    |                    |
    |                    hidden type `Pin<&Foo>` captures the anonymous lifetime defined here
    |
-help: to declare that the `impl Trait` captures `'_`, you can add an explicit `'_` lifetime bound
+help: to declare that `impl Clone` captures `'_`, you can add an explicit `'_` lifetime bound
    |
 LL |     fn f(self: Pin<&Self>) -> impl Clone + '_ { self }
    |                                          ++++
diff --git a/src/test/ui/self/class-missing-self.stderr b/src/test/ui/self/class-missing-self.stderr
index d501200d73ce..063c3f013c53 100644
--- a/src/test/ui/self/class-missing-self.stderr
+++ b/src/test/ui/self/class-missing-self.stderr
@@ -10,6 +10,10 @@ error[E0425]: cannot find function `sleep` in this scope
 LL |       sleep();
    |       ^^^^^ not found in this scope
    |
+help: consider using the associated function
+   |
+LL |       self.sleep();
+   |       +++++
 help: consider importing this function
    |
 LL | use std::thread::sleep;
diff --git a/src/test/ui/sized/coinductive-1-gat.rs b/src/test/ui/sized/coinductive-1-gat.rs
new file mode 100644
index 000000000000..cdf70920f009
--- /dev/null
+++ b/src/test/ui/sized/coinductive-1-gat.rs
@@ -0,0 +1,14 @@
+// check-pass
+struct Node<C: Trait>(C::Assoc::<Self>);
+
+trait Trait {
+    type Assoc<T>;
+}
+
+impl Trait for Vec<()> {
+    type Assoc<T> = Vec<T>;
+}
+
+fn main() {
+    let _ = Node::<Vec<()>>(Vec::new());
+}
diff --git a/src/test/ui/sized/coinductive-1.rs b/src/test/ui/sized/coinductive-1.rs
new file mode 100644
index 000000000000..7bcd0f1fdaf6
--- /dev/null
+++ b/src/test/ui/sized/coinductive-1.rs
@@ -0,0 +1,14 @@
+// check-pass
+struct Node<C: Trait<Self>>(C::Assoc);
+
+trait Trait<T> {
+    type Assoc;
+}
+
+impl<T> Trait<T> for Vec<()> {
+    type Assoc = Vec<T>;
+}
+
+fn main() {
+    let _ = Node::<Vec<()>>(Vec::new());
+}
diff --git a/src/test/ui/sized/coinductive-2.rs b/src/test/ui/sized/coinductive-2.rs
new file mode 100644
index 000000000000..212274d2e4b6
--- /dev/null
+++ b/src/test/ui/sized/coinductive-2.rs
@@ -0,0 +1,28 @@
+// run-pass
+struct Node<C: CollectionFactory<Self>> {
+    _children: C::Collection,
+}
+
+trait CollectionFactory<T> {
+    type Collection;
+}
+
+impl<T> CollectionFactory<T> for Vec<()> {
+    type Collection = Vec<T>;
+}
+
+trait Collection<T>: Sized {
+    fn push(&mut self, v: T);
+}
+
+impl<T> Collection<T> for Vec<T> {
+    fn push(&mut self, v: T) {
+        self.push(v)
+    }
+}
+
+fn main() {
+    let _ = Node::<Vec<()>> {
+        _children: Vec::new(),
+    };
+}
diff --git a/src/test/ui/sized/recursive-type-1.rs b/src/test/ui/sized/recursive-type-1.rs
new file mode 100644
index 000000000000..cd6805967e52
--- /dev/null
+++ b/src/test/ui/sized/recursive-type-1.rs
@@ -0,0 +1,10 @@
+// check-pass
+trait A { type Assoc; }
+
+impl A for () {
+    // FIXME: it would be nice for this to at least cause a warning.
+    type Assoc = Foo<()>;
+}
+struct Foo<T: A>(T::Assoc);
+
+fn main() {}
diff --git a/src/test/ui/sized/recursive-type-2.rs b/src/test/ui/sized/recursive-type-2.rs
new file mode 100644
index 000000000000..7d95417a6ffd
--- /dev/null
+++ b/src/test/ui/sized/recursive-type-2.rs
@@ -0,0 +1,13 @@
+// build-fail
+//~^ ERROR cycle detected when computing layout of `Foo<()>`
+
+trait A { type Assoc: ?Sized; }
+
+impl A for () {
+    type Assoc = Foo<()>;
+}
+struct Foo<T: A>(T::Assoc);
+
+fn main() {
+    let x: Foo<()>;
+}
diff --git a/src/test/ui/sized/recursive-type-2.stderr b/src/test/ui/sized/recursive-type-2.stderr
new file mode 100644
index 000000000000..d0e6e9db07e9
--- /dev/null
+++ b/src/test/ui/sized/recursive-type-2.stderr
@@ -0,0 +1,13 @@
+error[E0391]: cycle detected when computing layout of `Foo<()>`
+   |
+   = note: ...which requires computing layout of `<() as A>::Assoc`...
+   = note: ...which again requires computing layout of `Foo<()>`, completing the cycle
+note: cycle used when elaborating drops for `main`
+  --> $DIR/recursive-type-2.rs:11:1
+   |
+LL | fn main() {
+   | ^^^^^^^^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0391`.
diff --git a/src/test/ui/span/borrowck-let-suggestion-suffixes.rs b/src/test/ui/span/borrowck-let-suggestion-suffixes.rs
index 6240f103c99b..18abfb5c3fbe 100644
--- a/src/test/ui/span/borrowck-let-suggestion-suffixes.rs
+++ b/src/test/ui/span/borrowck-let-suggestion-suffixes.rs
@@ -18,7 +18,7 @@ fn f() {
 
     v3.push(&id('x'));           // statement 6
     //~^ ERROR temporary value dropped while borrowed
-    //~| NOTE creates a temporary which is freed while still in use
+    //~| NOTE creates a temporary value which is freed while still in use
     //~| NOTE temporary value is freed at the end of this statement
     //~| HELP consider using a `let` binding to create a longer lived value
 
@@ -28,7 +28,7 @@ fn f() {
 
         v4.push(&id('y'));
         //~^ ERROR temporary value dropped while borrowed
-        //~| NOTE creates a temporary which is freed while still in use
+        //~| NOTE creates a temporary value which is freed while still in use
         //~| NOTE temporary value is freed at the end of this statement
         //~| NOTE consider using a `let` binding to create a longer lived value
         v4.use_ref();
@@ -39,7 +39,7 @@ fn f() {
 
     v5.push(&id('z'));
     //~^ ERROR temporary value dropped while borrowed
-    //~| NOTE creates a temporary which is freed while still in use
+    //~| NOTE creates a temporary value which is freed while still in use
     //~| NOTE temporary value is freed at the end of this statement
     //~| HELP consider using a `let` binding to create a longer lived value
 
diff --git a/src/test/ui/span/borrowck-let-suggestion-suffixes.stderr b/src/test/ui/span/borrowck-let-suggestion-suffixes.stderr
index a236dab3ae56..2dc29a78d204 100644
--- a/src/test/ui/span/borrowck-let-suggestion-suffixes.stderr
+++ b/src/test/ui/span/borrowck-let-suggestion-suffixes.stderr
@@ -16,7 +16,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     v3.push(&id('x'));           // statement 6
    |              ^^^^^^^ - temporary value is freed at the end of this statement
    |              |
-   |              creates a temporary which is freed while still in use
+   |              creates a temporary value which is freed while still in use
 ...
 LL |     (v1, v2, v3, /* v4 is above. */ v5).use_ref();
    |              -- borrow later used here
@@ -33,7 +33,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |         v4.push(&id('y'));
    |                  ^^^^^^^ - temporary value is freed at the end of this statement
    |                  |
-   |                  creates a temporary which is freed while still in use
+   |                  creates a temporary value which is freed while still in use
 ...
 LL |         v4.use_ref();
    |         ------------ borrow later used here
@@ -46,7 +46,7 @@ error[E0716]: temporary value dropped while borrowed
 LL |     v5.push(&id('z'));
    |              ^^^^^^^ - temporary value is freed at the end of this statement
    |              |
-   |              creates a temporary which is freed while still in use
+   |              creates a temporary value which is freed while still in use
 ...
 LL |     (v1, v2, v3, /* v4 is above. */ v5).use_ref();
    |                                     -- borrow later used here
diff --git a/src/test/ui/span/borrowck-ref-into-rvalue.stderr b/src/test/ui/span/borrowck-ref-into-rvalue.stderr
index cb5289d24b4f..25e344fedfb2 100644
--- a/src/test/ui/span/borrowck-ref-into-rvalue.stderr
+++ b/src/test/ui/span/borrowck-ref-into-rvalue.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/borrowck-ref-into-rvalue.rs:4:11
    |
 LL |     match Some("Hello".to_string()) {
-   |           ^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |           ^^^^^^^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
 ...
 LL |     }
    |     - temporary value is freed at the end of this statement
diff --git a/src/test/ui/span/issue-11925.rs b/src/test/ui/span/issue-11925.rs
index d9c08fbdd0f1..cac9fd5bfb68 100644
--- a/src/test/ui/span/issue-11925.rs
+++ b/src/test/ui/span/issue-11925.rs
@@ -1,6 +1,6 @@
-#![feature(unboxed_closures)]
+#![feature(unboxed_closures, tuple_trait)]
 
-fn to_fn_once<A,F:FnOnce<A>>(f: F) -> F { f }
+fn to_fn_once<A:std::marker::Tuple,F:FnOnce<A>>(f: F) -> F { f }
 
 fn main() {
     let r = {
diff --git a/src/test/ui/span/issue-15480.stderr b/src/test/ui/span/issue-15480.stderr
index 460ad9ac7444..d9cce2254dd9 100644
--- a/src/test/ui/span/issue-15480.stderr
+++ b/src/test/ui/span/issue-15480.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/issue-15480.rs:6:10
    |
 LL |         &id(3)
-   |          ^^^^^ creates a temporary which is freed while still in use
+   |          ^^^^^ creates a temporary value which is freed while still in use
 LL |     ];
    |      - temporary value is freed at the end of this statement
 ...
diff --git a/src/test/ui/span/issue-35987.stderr b/src/test/ui/span/issue-35987.stderr
index d8fddc8007f5..057d40ac0cb9 100644
--- a/src/test/ui/span/issue-35987.stderr
+++ b/src/test/ui/span/issue-35987.stderr
@@ -1,6 +1,9 @@
 error[E0404]: expected trait, found type parameter `Add`
   --> $DIR/issue-35987.rs:5:21
    |
+LL | use std::ops::Add;
+   |               --- you might have meant to refer to this trait
+LL |
 LL | impl<T: Clone, Add> Add for Foo<T> {
    |                ---  ^^^ not a trait
    |                |
diff --git a/src/test/ui/span/regions-close-over-borrowed-ref-in-obj.stderr b/src/test/ui/span/regions-close-over-borrowed-ref-in-obj.stderr
index ba0c45acf237..81e858fa0ce0 100644
--- a/src/test/ui/span/regions-close-over-borrowed-ref-in-obj.stderr
+++ b/src/test/ui/span/regions-close-over-borrowed-ref-in-obj.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/regions-close-over-borrowed-ref-in-obj.rs:12:27
    |
 LL |         let ss: &isize = &id(1);
-   |                           ^^^^^ creates a temporary which is freed while still in use
+   |                           ^^^^^ creates a temporary value which is freed while still in use
 ...
 LL |     }
    |     - temporary value is freed at the end of this statement
diff --git a/src/test/ui/span/slice-borrow.stderr b/src/test/ui/span/slice-borrow.stderr
index 27df25be3fa0..b70bf69d688a 100644
--- a/src/test/ui/span/slice-borrow.stderr
+++ b/src/test/ui/span/slice-borrow.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/slice-borrow.rs:6:28
    |
 LL |         let x: &[isize] = &vec![1, 2, 3, 4, 5];
-   |                            ^^^^^^^^^^^^^^^^^^^ creates a temporary which is freed while still in use
+   |                            ^^^^^^^^^^^^^^^^^^^ creates a temporary value which is freed while still in use
 ...
 LL |     }
    |     - temporary value is freed at the end of this statement
diff --git a/src/test/ui/specialization/specialization-overlap-negative.stderr b/src/test/ui/specialization/specialization-overlap-negative.stderr
index fb3d9723aff8..1fe4869ff548 100644
--- a/src/test/ui/specialization/specialization-overlap-negative.stderr
+++ b/src/test/ui/specialization/specialization-overlap-negative.stderr
@@ -8,7 +8,7 @@ LL | #![feature(specialization)]
    = help: consider using `min_specialization` instead, which is more stable and complete
    = note: `#[warn(incomplete_features)]` on by default
 
-error[E0751]: found both positive and negative implementation of trait `std::marker::Send` for type `TestType<_>`:
+error[E0751]: found both positive and negative implementation of trait `Send` for type `TestType<_>`:
   --> $DIR/specialization-overlap-negative.rs:9:1
    |
 LL | unsafe impl<T: Clone> Send for TestType<T> {}
diff --git a/src/test/ui/specialization/specialization-overlap.stderr b/src/test/ui/specialization/specialization-overlap.stderr
index 98926446765a..098bf4a70ab4 100644
--- a/src/test/ui/specialization/specialization-overlap.stderr
+++ b/src/test/ui/specialization/specialization-overlap.stderr
@@ -8,13 +8,13 @@ LL | #![feature(specialization)]
    = help: consider using `min_specialization` instead, which is more stable and complete
    = note: `#[warn(incomplete_features)]` on by default
 
-error[E0119]: conflicting implementations of trait `Foo` for type `std::vec::Vec<_>`
+error[E0119]: conflicting implementations of trait `Foo` for type `Vec<_>`
   --> $DIR/specialization-overlap.rs:5:1
    |
 LL | impl<T: Clone> Foo for T {}
    | ------------------------ first implementation here
 LL | impl<T> Foo for Vec<T> {}
-   | ^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `std::vec::Vec<_>`
+   | ^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `Vec<_>`
 
 error[E0119]: conflicting implementations of trait `Bar` for type `(u8, u8)`
   --> $DIR/specialization-overlap.rs:9:1
diff --git a/src/test/ui/issues/issue-5216.rs b/src/test/ui/static/issue-5216.rs
similarity index 100%
rename from src/test/ui/issues/issue-5216.rs
rename to src/test/ui/static/issue-5216.rs
diff --git a/src/test/ui/issues/issue-5216.stderr b/src/test/ui/static/issue-5216.stderr
similarity index 100%
rename from src/test/ui/issues/issue-5216.stderr
rename to src/test/ui/static/issue-5216.stderr
diff --git a/src/test/ui/static/static-drop-scope.stderr b/src/test/ui/static/static-drop-scope.stderr
index 112bfc003048..cedcb7367949 100644
--- a/src/test/ui/static/static-drop-scope.stderr
+++ b/src/test/ui/static/static-drop-scope.stderr
@@ -13,7 +13,7 @@ LL | static PROMOTION_FAIL_S: Option<&'static WithDtor> = Some(&WithDtor);
    |                                                      ------^^^^^^^^-
    |                                                      |     |       |
    |                                                      |     |       temporary value is freed at the end of this statement
-   |                                                      |     creates a temporary which is freed while still in use
+   |                                                      |     creates a temporary value which is freed while still in use
    |                                                      using this value as a static requires that borrow lasts for `'static`
 
 error[E0493]: destructor of `WithDtor` cannot be evaluated at compile-time
@@ -31,7 +31,7 @@ LL | const PROMOTION_FAIL_C: Option<&'static WithDtor> = Some(&WithDtor);
    |                                                     ------^^^^^^^^-
    |                                                     |     |       |
    |                                                     |     |       temporary value is freed at the end of this statement
-   |                                                     |     creates a temporary which is freed while still in use
+   |                                                     |     creates a temporary value which is freed while still in use
    |                                                     using this value as a constant requires that borrow lasts for `'static`
 
 error[E0493]: destructor of `(WithDtor, i32)` cannot be evaluated at compile-time
diff --git a/src/test/ui/static/static-reference-to-fn-2.stderr b/src/test/ui/static/static-reference-to-fn-2.stderr
index ff15884bd445..133d8ec2e1e5 100644
--- a/src/test/ui/static/static-reference-to-fn-2.stderr
+++ b/src/test/ui/static/static-reference-to-fn-2.stderr
@@ -6,7 +6,7 @@ LL | fn state1(self_: &mut StateMachineIter) -> Option<&'static str> {
 LL |     self_.statefn = &id(state2 as StateMachineFunc);
    |     -----------------^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^- temporary value is freed at the end of this statement
    |     |                |
-   |     |                creates a temporary which is freed while still in use
+   |     |                creates a temporary value which is freed while still in use
    |     assignment requires that borrow lasts for `'1`
 
 error[E0716]: temporary value dropped while borrowed
@@ -17,7 +17,7 @@ LL | fn state2(self_: &mut StateMachineIter) -> Option<(&'static str)> {
 LL |     self_.statefn = &id(state3 as StateMachineFunc);
    |     -----------------^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^- temporary value is freed at the end of this statement
    |     |                |
-   |     |                creates a temporary which is freed while still in use
+   |     |                creates a temporary value which is freed while still in use
    |     assignment requires that borrow lasts for `'1`
 
 error[E0716]: temporary value dropped while borrowed
@@ -28,7 +28,7 @@ LL | fn state3(self_: &mut StateMachineIter) -> Option<(&'static str)> {
 LL |     self_.statefn = &id(finished as StateMachineFunc);
    |     -----------------^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^- temporary value is freed at the end of this statement
    |     |                |
-   |     |                creates a temporary which is freed while still in use
+   |     |                creates a temporary value which is freed while still in use
    |     assignment requires that borrow lasts for `'1`
 
 error[E0515]: cannot return value referencing temporary value
diff --git a/src/test/ui/static/static-region-bound.stderr b/src/test/ui/static/static-region-bound.stderr
index 15261259ed41..1a607e3c014a 100644
--- a/src/test/ui/static/static-region-bound.stderr
+++ b/src/test/ui/static/static-region-bound.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/static-region-bound.rs:10:14
    |
 LL |     let x = &id(3);
-   |              ^^^^^ creates a temporary which is freed while still in use
+   |              ^^^^^ creates a temporary value which is freed while still in use
 LL |     f(x);
    |     ---- argument requires that borrow lasts for `'static`
 LL | }
diff --git a/src/test/ui/statics/issue-44373.stderr b/src/test/ui/statics/issue-44373.stderr
index 6f92fbb1eb68..2d29dec888e8 100644
--- a/src/test/ui/statics/issue-44373.stderr
+++ b/src/test/ui/statics/issue-44373.stderr
@@ -2,7 +2,7 @@ error[E0716]: temporary value dropped while borrowed
   --> $DIR/issue-44373.rs:4:42
    |
 LL |     let _val: &'static [&'static u32] = &[&FOO];
-   |               -----------------------    ^^^^^^ creates a temporary which is freed while still in use
+   |               -----------------------    ^^^^^^ creates a temporary value which is freed while still in use
    |               |
    |               type annotation requires that borrow lasts for `'static`
 LL | }
diff --git a/src/test/ui/suggestions/assoc_fn_without_self.stderr b/src/test/ui/suggestions/assoc_fn_without_self.stderr
index 88920b852905..febdd67338c9 100644
--- a/src/test/ui/suggestions/assoc_fn_without_self.stderr
+++ b/src/test/ui/suggestions/assoc_fn_without_self.stderr
@@ -7,13 +7,18 @@ LL |         foo();
 help: consider using the associated function
    |
 LL |         Self::foo();
-   |         ~~~~~~~~~
+   |         ++++++
 
 error[E0425]: cannot find function `bar` in this scope
   --> $DIR/assoc_fn_without_self.rs:17:9
    |
 LL |         bar();
    |         ^^^ not found in this scope
+   |
+help: consider using the associated function
+   |
+LL |         self.bar();
+   |         +++++
 
 error[E0425]: cannot find function `baz` in this scope
   --> $DIR/assoc_fn_without_self.rs:18:9
@@ -24,7 +29,7 @@ LL |         baz(2, 3);
 help: consider using the associated function
    |
 LL |         Self::baz(2, 3);
-   |         ~~~~~~~~~
+   |         ++++++
 
 error[E0425]: cannot find function `foo` in this scope
   --> $DIR/assoc_fn_without_self.rs:14:13
diff --git a/src/test/ui/suggestions/core-std-import-order-issue-83564.stderr b/src/test/ui/suggestions/core-std-import-order-issue-83564.stderr
index ce85d93b96ca..e4e1fc591c47 100644
--- a/src/test/ui/suggestions/core-std-import-order-issue-83564.stderr
+++ b/src/test/ui/suggestions/core-std-import-order-issue-83564.stderr
@@ -2,7 +2,7 @@ error[E0433]: failed to resolve: use of undeclared type `NonZeroU32`
   --> $DIR/core-std-import-order-issue-83564.rs:8:14
    |
 LL |     let _x = NonZeroU32::new(5).unwrap();
-   |              ^^^^^^^^^^ not found in this scope
+   |              ^^^^^^^^^^ use of undeclared type `NonZeroU32`
    |
 help: consider importing one of these items
    |
diff --git a/src/test/ui/suggestions/dont-suggest-ufcs-for-const.rs b/src/test/ui/suggestions/dont-suggest-ufcs-for-const.rs
new file mode 100644
index 000000000000..06cf243f1b4f
--- /dev/null
+++ b/src/test/ui/suggestions/dont-suggest-ufcs-for-const.rs
@@ -0,0 +1,4 @@
+fn main() {
+    1_u32.MAX();
+    //~^ ERROR no method named `MAX` found for type `u32` in the current scope
+}
diff --git a/src/test/ui/suggestions/dont-suggest-ufcs-for-const.stderr b/src/test/ui/suggestions/dont-suggest-ufcs-for-const.stderr
new file mode 100644
index 000000000000..04e0511d788e
--- /dev/null
+++ b/src/test/ui/suggestions/dont-suggest-ufcs-for-const.stderr
@@ -0,0 +1,15 @@
+error[E0599]: no method named `MAX` found for type `u32` in the current scope
+  --> $DIR/dont-suggest-ufcs-for-const.rs:2:11
+   |
+LL |     1_u32.MAX();
+   |     ------^^^--
+   |     |     |
+   |     |     this is an associated function, not a method
+   |     help: use associated function syntax instead: `u32::MAX()`
+   |
+   = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
+   = note: the candidate is defined in an impl for the type `u32`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0599`.
diff --git a/src/test/ui/suggestions/format-borrow.stderr b/src/test/ui/suggestions/format-borrow.stderr
index fac6a5a5f48c..8ed2b9c9a633 100644
--- a/src/test/ui/suggestions/format-borrow.stderr
+++ b/src/test/ui/suggestions/format-borrow.stderr
@@ -11,6 +11,10 @@ help: consider removing the borrow
 LL -     let a: String = &String::from("a");
 LL +     let a: String = String::from("a");
    |
+help: alternatively, consider changing the type annotation
+   |
+LL |     let a: &String = &String::from("a");
+   |            +
 
 error[E0308]: mismatched types
   --> $DIR/format-borrow.rs:4:21
@@ -25,6 +29,10 @@ help: consider removing the borrow
 LL -     let b: String = &format!("b");
 LL +     let b: String = format!("b");
    |
+help: alternatively, consider changing the type annotation
+   |
+LL |     let b: &String = &format!("b");
+   |            +
 
 error[E0308]: mismatched types
   --> $DIR/format-borrow.rs:6:21
@@ -39,6 +47,10 @@ help: consider removing the borrow
 LL -     let c: String = &mut format!("c");
 LL +     let c: String = format!("c");
    |
+help: alternatively, consider changing the type annotation
+   |
+LL |     let c: &mut String = &mut format!("c");
+   |            ++++
 
 error[E0308]: mismatched types
   --> $DIR/format-borrow.rs:8:21
@@ -53,6 +65,10 @@ help: consider removing the borrow
 LL -     let d: String = &mut (format!("d"));
 LL +     let d: String = format!("d"));
    |
+help: alternatively, consider changing the type annotation
+   |
+LL |     let d: &mut String = &mut (format!("d"));
+   |            ++++
 
 error: aborting due to 4 previous errors
 
diff --git a/src/test/ui/suggestions/if-let-typo.stderr b/src/test/ui/suggestions/if-let-typo.stderr
index 3d9ac40ec367..02148b7f7adf 100644
--- a/src/test/ui/suggestions/if-let-typo.stderr
+++ b/src/test/ui/suggestions/if-let-typo.stderr
@@ -25,12 +25,22 @@ error[E0308]: mismatched types
    |
 LL |     if Some(x) = foo {}
    |        ^^^^^^^^^^^^^ expected `bool`, found `()`
+   |
+help: consider adding `let`
+   |
+LL |     if let Some(x) = foo {}
+   |        +++
 
 error[E0308]: mismatched types
   --> $DIR/if-let-typo.rs:6:8
    |
 LL |     if Some(foo) = bar {}
    |        ^^^^^^^^^^^^^^^ expected `bool`, found `()`
+   |
+help: consider adding `let`
+   |
+LL |     if let Some(foo) = bar {}
+   |        +++
 
 error[E0308]: mismatched types
   --> $DIR/if-let-typo.rs:7:8
@@ -51,6 +61,11 @@ error[E0308]: mismatched types
    |
 LL |     if Some(3) = foo {}
    |        ^^^^^^^^^^^^^ expected `bool`, found `()`
+   |
+help: consider adding `let`
+   |
+LL |     if let Some(3) = foo {}
+   |        +++
 
 error: aborting due to 7 previous errors
 
diff --git a/src/test/ui/suggestions/inner_type2.rs b/src/test/ui/suggestions/inner_type2.rs
index c56ea7c030d8..fac68c053eb4 100644
--- a/src/test/ui/suggestions/inner_type2.rs
+++ b/src/test/ui/suggestions/inner_type2.rs
@@ -22,5 +22,5 @@ fn main() {
     let item = std::mem::MaybeUninit::new(Struct { p: 42_u32 });
     item.method();
     //~^ ERROR no method named `method` found for union `MaybeUninit` in the current scope [E0599]
-    //~| HELP if this `MaybeUninit::<Struct<u32>>` has been initialized, use one of the `assume_init` methods to access the inner value
+    //~| HELP if this `MaybeUninit<Struct<u32>>` has been initialized, use one of the `assume_init` methods to access the inner value
 }
diff --git a/src/test/ui/suggestions/inner_type2.stderr b/src/test/ui/suggestions/inner_type2.stderr
index eddfd9d63409..984366123c82 100644
--- a/src/test/ui/suggestions/inner_type2.stderr
+++ b/src/test/ui/suggestions/inner_type2.stderr
@@ -17,7 +17,7 @@ error[E0599]: no method named `method` found for union `MaybeUninit` in the curr
 LL |     item.method();
    |          ^^^^^^ method not found in `MaybeUninit<Struct<u32>>`
    |
-   = help: if this `MaybeUninit::<Struct<u32>>` has been initialized, use one of the `assume_init` methods to access the inner value
+   = help: if this `MaybeUninit<Struct<u32>>` has been initialized, use one of the `assume_init` methods to access the inner value
 note: the method `method` exists on the type `Struct<u32>`
   --> $DIR/inner_type2.rs:6:5
    |
diff --git a/src/test/ui/suggestions/issue-102354.rs b/src/test/ui/suggestions/issue-102354.rs
new file mode 100644
index 000000000000..f881feb0060a
--- /dev/null
+++ b/src/test/ui/suggestions/issue-102354.rs
@@ -0,0 +1,10 @@
+trait Trait {
+    fn func() {}
+}
+
+impl Trait for i32 {}
+
+fn main() {
+    let x: i32 = 123;
+    x.func(); //~ERROR no method
+}
diff --git a/src/test/ui/suggestions/issue-102354.stderr b/src/test/ui/suggestions/issue-102354.stderr
new file mode 100644
index 000000000000..b17c4dc5dfb5
--- /dev/null
+++ b/src/test/ui/suggestions/issue-102354.stderr
@@ -0,0 +1,24 @@
+error[E0599]: no method named `func` found for type `i32` in the current scope
+  --> $DIR/issue-102354.rs:9:7
+   |
+LL |     x.func();
+   |       ^^^^ this is an associated function, not a method
+   |
+   = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
+note: the candidate is defined in the trait `Trait`
+  --> $DIR/issue-102354.rs:2:5
+   |
+LL |     fn func() {}
+   |     ^^^^^^^^^
+help: use associated function syntax instead
+   |
+LL |     i32::func();
+   |     ~~~~~~~~~~~
+help: disambiguate the associated function for the candidate
+   |
+LL |     <i32 as Trait>::func(x);
+   |     ~~~~~~~~~~~~~~~~~~~~~~~
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0599`.
diff --git a/src/test/ui/suggestions/issue-102892.rs b/src/test/ui/suggestions/issue-102892.rs
new file mode 100644
index 000000000000..c1a791d8d857
--- /dev/null
+++ b/src/test/ui/suggestions/issue-102892.rs
@@ -0,0 +1,25 @@
+#![allow(dead_code, unused_variables)]
+
+use std::sync::Arc;
+
+#[derive(Debug)]
+struct A;
+#[derive(Debug)]
+struct B;
+
+fn process_without_annot(arc: &Arc<(A, B)>) {
+    let (a, b) = **arc; // suggests putting `&**arc` here; with that, fixed!
+}
+
+fn process_with_annot(arc: &Arc<(A, B)>) {
+    let (a, b): (A, B) = &**arc; // suggests putting `&**arc` here too
+    //~^ ERROR mismatched types
+}
+
+fn process_with_tuple_annot(mutation: &mut (A, B), arc: &Arc<(A, B)>) {
+    let (a, b): ((A, B), A) = (&mut *mutation, &(**arc).0); // suggests putting `&**arc` here too
+    //~^ ERROR mismatched types
+    //~| ERROR mismatched types
+}
+
+fn main() {}
diff --git a/src/test/ui/suggestions/issue-102892.stderr b/src/test/ui/suggestions/issue-102892.stderr
new file mode 100644
index 000000000000..a3dbc7cb861f
--- /dev/null
+++ b/src/test/ui/suggestions/issue-102892.stderr
@@ -0,0 +1,57 @@
+error[E0308]: mismatched types
+  --> $DIR/issue-102892.rs:15:26
+   |
+LL |     let (a, b): (A, B) = &**arc; // suggests putting `&**arc` here too
+   |                 ------   ^^^^^^ expected tuple, found `&(A, B)`
+   |                 |
+   |                 expected due to this
+   |
+   = note:  expected tuple `(A, B)`
+           found reference `&(A, B)`
+help: consider removing the borrow
+   |
+LL -     let (a, b): (A, B) = &**arc; // suggests putting `&**arc` here too
+LL +     let (a, b): (A, B) = **arc; // suggests putting `&**arc` here too
+   |
+help: alternatively, consider changing the type annotation
+   |
+LL |     let (a, b): &(A, B) = &**arc; // suggests putting `&**arc` here too
+   |                 +
+
+error[E0308]: mismatched types
+  --> $DIR/issue-102892.rs:20:32
+   |
+LL |     let (a, b): ((A, B), A) = (&mut *mutation, &(**arc).0); // suggests putting `&**arc` here too
+   |                                ^^^^^^^^^^^^^^ expected tuple, found `&mut (A, B)`
+   |
+   = note:          expected tuple `(A, B)`
+           found mutable reference `&mut (A, B)`
+help: consider removing the borrow
+   |
+LL -     let (a, b): ((A, B), A) = (&mut *mutation, &(**arc).0); // suggests putting `&**arc` here too
+LL +     let (a, b): ((A, B), A) = (*mutation, &(**arc).0); // suggests putting `&**arc` here too
+   |
+help: alternatively, consider changing the type annotation
+   |
+LL |     let (a, b): (&mut (A, B), A) = (&mut *mutation, &(**arc).0); // suggests putting `&**arc` here too
+   |                  ++++
+
+error[E0308]: mismatched types
+  --> $DIR/issue-102892.rs:20:48
+   |
+LL |     let (a, b): ((A, B), A) = (&mut *mutation, &(**arc).0); // suggests putting `&**arc` here too
+   |                                                ^^^^^^^^^^ expected struct `A`, found `&A`
+   |
+help: consider removing the borrow
+   |
+LL -     let (a, b): ((A, B), A) = (&mut *mutation, &(**arc).0); // suggests putting `&**arc` here too
+LL +     let (a, b): ((A, B), A) = (&mut *mutation, (**arc).0); // suggests putting `&**arc` here too
+   |
+help: alternatively, consider changing the type annotation
+   |
+LL |     let (a, b): ((A, B), &A) = (&mut *mutation, &(**arc).0); // suggests putting `&**arc` here too
+   |                          +
+
+error: aborting due to 3 previous errors
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/ui/suggestions/issue-104086-suggest-let.rs b/src/test/ui/suggestions/issue-104086-suggest-let.rs
new file mode 100644
index 000000000000..d22ad27d0e03
--- /dev/null
+++ b/src/test/ui/suggestions/issue-104086-suggest-let.rs
@@ -0,0 +1,30 @@
+fn main() {
+    x = x = x;
+    //~^ ERROR cannot find value `x` in this scope
+    //~| ERROR cannot find value `x` in this scope
+    //~| ERROR cannot find value `x` in this scope
+
+    x = y = y = y;
+    //~^ ERROR cannot find value `y` in this scope
+    //~| ERROR cannot find value `y` in this scope
+    //~| ERROR cannot find value `y` in this scope
+    //~| ERROR cannot find value `x` in this scope
+
+    x = y = y;
+    //~^ ERROR cannot find value `x` in this scope
+    //~| ERROR cannot find value `y` in this scope
+    //~| ERROR cannot find value `y` in this scope
+
+    x = x = y;
+    //~^ ERROR cannot find value `x` in this scope
+    //~| ERROR cannot find value `x` in this scope
+    //~| ERROR cannot find value `y` in this scope
+
+    x = x; // will suggest add `let`
+    //~^ ERROR cannot find value `x` in this scope
+    //~| ERROR cannot find value `x` in this scope
+
+    x = y // will suggest add `let`
+    //~^ ERROR cannot find value `x` in this scope
+    //~| ERROR cannot find value `y` in this scope
+}
diff --git a/src/test/ui/suggestions/issue-104086-suggest-let.stderr b/src/test/ui/suggestions/issue-104086-suggest-let.stderr
new file mode 100644
index 000000000000..fb4ea3121ac6
--- /dev/null
+++ b/src/test/ui/suggestions/issue-104086-suggest-let.stderr
@@ -0,0 +1,135 @@
+error[E0425]: cannot find value `x` in this scope
+  --> $DIR/issue-104086-suggest-let.rs:2:5
+   |
+LL |     x = x = x;
+   |     ^
+   |
+help: you might have meant to introduce a new binding
+   |
+LL |     let x = x = x;
+   |     +++
+
+error[E0425]: cannot find value `x` in this scope
+  --> $DIR/issue-104086-suggest-let.rs:2:9
+   |
+LL |     x = x = x;
+   |         ^ not found in this scope
+
+error[E0425]: cannot find value `x` in this scope
+  --> $DIR/issue-104086-suggest-let.rs:2:13
+   |
+LL |     x = x = x;
+   |             ^ not found in this scope
+
+error[E0425]: cannot find value `x` in this scope
+  --> $DIR/issue-104086-suggest-let.rs:7:5
+   |
+LL |     x = y = y = y;
+   |     ^
+   |
+help: you might have meant to introduce a new binding
+   |
+LL |     let x = y = y = y;
+   |     +++
+
+error[E0425]: cannot find value `y` in this scope
+  --> $DIR/issue-104086-suggest-let.rs:7:9
+   |
+LL |     x = y = y = y;
+   |         ^ not found in this scope
+
+error[E0425]: cannot find value `y` in this scope
+  --> $DIR/issue-104086-suggest-let.rs:7:13
+   |
+LL |     x = y = y = y;
+   |             ^ not found in this scope
+
+error[E0425]: cannot find value `y` in this scope
+  --> $DIR/issue-104086-suggest-let.rs:7:17
+   |
+LL |     x = y = y = y;
+   |                 ^ not found in this scope
+
+error[E0425]: cannot find value `x` in this scope
+  --> $DIR/issue-104086-suggest-let.rs:13:5
+   |
+LL |     x = y = y;
+   |     ^
+   |
+help: you might have meant to introduce a new binding
+   |
+LL |     let x = y = y;
+   |     +++
+
+error[E0425]: cannot find value `y` in this scope
+  --> $DIR/issue-104086-suggest-let.rs:13:9
+   |
+LL |     x = y = y;
+   |         ^ not found in this scope
+
+error[E0425]: cannot find value `y` in this scope
+  --> $DIR/issue-104086-suggest-let.rs:13:13
+   |
+LL |     x = y = y;
+   |             ^ not found in this scope
+
+error[E0425]: cannot find value `x` in this scope
+  --> $DIR/issue-104086-suggest-let.rs:18:5
+   |
+LL |     x = x = y;
+   |     ^
+   |
+help: you might have meant to introduce a new binding
+   |
+LL |     let x = x = y;
+   |     +++
+
+error[E0425]: cannot find value `x` in this scope
+  --> $DIR/issue-104086-suggest-let.rs:18:9
+   |
+LL |     x = x = y;
+   |         ^ not found in this scope
+
+error[E0425]: cannot find value `y` in this scope
+  --> $DIR/issue-104086-suggest-let.rs:18:13
+   |
+LL |     x = x = y;
+   |             ^ not found in this scope
+
+error[E0425]: cannot find value `x` in this scope
+  --> $DIR/issue-104086-suggest-let.rs:23:5
+   |
+LL |     x = x; // will suggest add `let`
+   |     ^
+   |
+help: you might have meant to introduce a new binding
+   |
+LL |     let x = x; // will suggest add `let`
+   |     +++
+
+error[E0425]: cannot find value `x` in this scope
+  --> $DIR/issue-104086-suggest-let.rs:23:9
+   |
+LL |     x = x; // will suggest add `let`
+   |         ^ not found in this scope
+
+error[E0425]: cannot find value `x` in this scope
+  --> $DIR/issue-104086-suggest-let.rs:27:5
+   |
+LL |     x = y // will suggest add `let`
+   |     ^
+   |
+help: you might have meant to introduce a new binding
+   |
+LL |     let x = y // will suggest add `let`
+   |     +++
+
+error[E0425]: cannot find value `y` in this scope
+  --> $DIR/issue-104086-suggest-let.rs:27:9
+   |
+LL |     x = y // will suggest add `let`
+   |         ^ not found in this scope
+
+error: aborting due to 17 previous errors
+
+For more information about this error, try `rustc --explain E0425`.
diff --git a/src/test/ui/suggestions/lifetimes/missing-lifetimes-in-signature.stderr b/src/test/ui/suggestions/lifetimes/missing-lifetimes-in-signature.stderr
index 171f4b333db4..fa758bf05df5 100644
--- a/src/test/ui/suggestions/lifetimes/missing-lifetimes-in-signature.stderr
+++ b/src/test/ui/suggestions/lifetimes/missing-lifetimes-in-signature.stderr
@@ -18,7 +18,7 @@ LL | |         *dest = g.get();
 LL | |     }
    | |_____^
    |
-help: to declare that the `impl Trait` captures `'_`, you can add an explicit `'_` lifetime bound
+help: to declare that `impl FnOnce()` captures `'_`, you can add an explicit `'_` lifetime bound
    |
 LL | fn foo<G, T>(g: G, dest: &mut T) -> impl FnOnce() + '_
    |                                                   ++++
diff --git a/src/test/ui/suggestions/lifetimes/trait-object-nested-in-impl-trait.stderr b/src/test/ui/suggestions/lifetimes/trait-object-nested-in-impl-trait.stderr
index f49876bcd3f1..c77ef79e7ed1 100644
--- a/src/test/ui/suggestions/lifetimes/trait-object-nested-in-impl-trait.stderr
+++ b/src/test/ui/suggestions/lifetimes/trait-object-nested-in-impl-trait.stderr
@@ -10,7 +10,7 @@ LL | |             remaining: self.0.iter(),
 LL | |         }
    | |_________^ returning this value requires that `'1` must outlive `'static`
    |
-help: to declare that the `impl Trait` captures data from argument `self`, you can add an explicit `'_` lifetime bound
+help: to declare that `impl Iterator<Item = Box<(dyn Foo + 'static)>>` captures data from argument `self`, you can add an explicit `'_` lifetime bound
    |
 LL |     fn iter(&self) -> impl Iterator<Item = Box<dyn Foo>> + '_ {
    |                                                          ++++
@@ -65,7 +65,7 @@ LL | |             remaining: self.0.iter(),
 LL | |         }
    | |_________^ returning this value requires that `'a` must outlive `'static`
    |
-help: to declare that the `impl Trait` captures data from argument `self`, you can add an explicit `'a` lifetime bound
+help: to declare that `impl Iterator<Item = Box<(dyn Foo + 'static)>>` captures data from argument `self`, you can add an explicit `'a` lifetime bound
    |
 LL |     fn iter<'a>(&'a self) -> impl Iterator<Item = Box<dyn Foo>> + 'a {
    |                                                                 ++++
diff --git a/src/test/ui/suggestions/multibyte-escapes.rs b/src/test/ui/suggestions/multibyte-escapes.rs
index fd5d46a4e923..c4105186244d 100644
--- a/src/test/ui/suggestions/multibyte-escapes.rs
+++ b/src/test/ui/suggestions/multibyte-escapes.rs
@@ -2,17 +2,17 @@
 
 fn main() {
     b'µ';
-    //~^ ERROR: non-ASCII character in byte constant
+    //~^ ERROR: non-ASCII character in byte literal
     //~| HELP: if you meant to use the unicode code point for 'µ', use a \xHH escape
-    //~| NOTE: byte constant must be ASCII
+    //~| NOTE: must be ASCII
 
     b'字';
-    //~^ ERROR: non-ASCII character in byte constant
+    //~^ ERROR: non-ASCII character in byte literal
     //~| NOTE: this multibyte character does not fit into a single byte
-    //~| NOTE: byte constant must be ASCII
+    //~| NOTE: must be ASCII
 
     b"字";
-    //~^ ERROR: non-ASCII character in byte constant
+    //~^ ERROR: non-ASCII character in byte string literal
     //~| HELP: if you meant to use the UTF-8 encoding of '字', use \xHH escapes
-    //~| NOTE: byte constant must be ASCII
+    //~| NOTE: must be ASCII
 }
diff --git a/src/test/ui/suggestions/multibyte-escapes.stderr b/src/test/ui/suggestions/multibyte-escapes.stderr
index 6e26bc1f01ce..1e7c43e6538f 100644
--- a/src/test/ui/suggestions/multibyte-escapes.stderr
+++ b/src/test/ui/suggestions/multibyte-escapes.stderr
@@ -1,28 +1,28 @@
-error: non-ASCII character in byte constant
+error: non-ASCII character in byte literal
   --> $DIR/multibyte-escapes.rs:4:7
    |
 LL |     b'µ';
-   |       ^ byte constant must be ASCII
+   |       ^ must be ASCII
    |
 help: if you meant to use the unicode code point for 'µ', use a \xHH escape
    |
 LL |     b'\xB5';
    |       ~~~~
 
-error: non-ASCII character in byte constant
+error: non-ASCII character in byte literal
   --> $DIR/multibyte-escapes.rs:9:7
    |
 LL |     b'字';
    |       ^^
    |       |
-   |       byte constant must be ASCII
+   |       must be ASCII
    |       this multibyte character does not fit into a single byte
 
-error: non-ASCII character in byte constant
+error: non-ASCII character in byte string literal
   --> $DIR/multibyte-escapes.rs:14:7
    |
 LL |     b"字";
-   |       ^^ byte constant must be ASCII
+   |       ^^ must be ASCII
    |
 help: if you meant to use the UTF-8 encoding of '字', use \xHH escapes
    |
diff --git a/src/test/ui/suggestions/option-to-bool.rs b/src/test/ui/suggestions/option-to-bool.rs
new file mode 100644
index 000000000000..2a1823b15f58
--- /dev/null
+++ b/src/test/ui/suggestions/option-to-bool.rs
@@ -0,0 +1,9 @@
+#![cfg_attr(let_chains, feature(let_chains))]
+
+fn foo(x: Option<i32>) {
+    if true && x {}
+    //~^ ERROR mismatched types
+    //~| HELP use `Option::is_some` to test if the `Option` has a value
+}
+
+fn main() {}
diff --git a/src/test/ui/suggestions/option-to-bool.stderr b/src/test/ui/suggestions/option-to-bool.stderr
new file mode 100644
index 000000000000..57a934b83420
--- /dev/null
+++ b/src/test/ui/suggestions/option-to-bool.stderr
@@ -0,0 +1,16 @@
+error[E0308]: mismatched types
+  --> $DIR/option-to-bool.rs:4:16
+   |
+LL |     if true && x {}
+   |                ^ expected `bool`, found enum `Option`
+   |
+   = note: expected type `bool`
+              found enum `Option<i32>`
+help: use `Option::is_some` to test if the `Option` has a value
+   |
+LL |     if true && x.is_some() {}
+   |                 ++++++++++
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/ui/suggestions/suggest-assoc-fn-call-deref.fixed b/src/test/ui/suggestions/suggest-assoc-fn-call-deref.fixed
new file mode 100644
index 000000000000..8d96cf590c39
--- /dev/null
+++ b/src/test/ui/suggestions/suggest-assoc-fn-call-deref.fixed
@@ -0,0 +1,15 @@
+// run-rustfix
+
+#![allow(unused)]
+
+struct Foo<T>(T);
+
+impl<T> Foo<T> {
+    fn test() -> i32 { 1 }
+}
+
+fn main() {
+    let x = Box::new(Foo(1i32));
+    Foo::<i32>::test();
+    //~^ ERROR no method named `test` found for struct `Box<Foo<i32>>` in the current scope
+}
diff --git a/src/test/ui/suggestions/suggest-assoc-fn-call-deref.rs b/src/test/ui/suggestions/suggest-assoc-fn-call-deref.rs
new file mode 100644
index 000000000000..186901f75a84
--- /dev/null
+++ b/src/test/ui/suggestions/suggest-assoc-fn-call-deref.rs
@@ -0,0 +1,15 @@
+// run-rustfix
+
+#![allow(unused)]
+
+struct Foo<T>(T);
+
+impl<T> Foo<T> {
+    fn test() -> i32 { 1 }
+}
+
+fn main() {
+    let x = Box::new(Foo(1i32));
+    x.test();
+    //~^ ERROR no method named `test` found for struct `Box<Foo<i32>>` in the current scope
+}
diff --git a/src/test/ui/suggestions/suggest-assoc-fn-call-deref.stderr b/src/test/ui/suggestions/suggest-assoc-fn-call-deref.stderr
new file mode 100644
index 000000000000..00fb96f03266
--- /dev/null
+++ b/src/test/ui/suggestions/suggest-assoc-fn-call-deref.stderr
@@ -0,0 +1,19 @@
+error[E0599]: no method named `test` found for struct `Box<Foo<i32>>` in the current scope
+  --> $DIR/suggest-assoc-fn-call-deref.rs:13:7
+   |
+LL |     x.test();
+   |     --^^^^--
+   |     | |
+   |     | this is an associated function, not a method
+   |     help: use associated function syntax instead: `Foo::<i32>::test()`
+   |
+   = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
+note: the candidate is defined in an impl for the type `Foo<T>`
+  --> $DIR/suggest-assoc-fn-call-deref.rs:8:5
+   |
+LL |     fn test() -> i32 { 1 }
+   |     ^^^^^^^^^^^^^^^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0599`.
diff --git a/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish-placeholder.rs b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish-placeholder.rs
new file mode 100644
index 000000000000..a39b8711dd87
--- /dev/null
+++ b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish-placeholder.rs
@@ -0,0 +1,11 @@
+struct GenericAssocMethod<T>(T);
+
+impl<T> GenericAssocMethod<T> {
+    fn default_hello() {}
+}
+
+fn main() {
+    let x = GenericAssocMethod(33);
+    x.default_hello();
+    //~^ ERROR no method named `default_hello` found
+}
diff --git a/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish-placeholder.stderr b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish-placeholder.stderr
new file mode 100644
index 000000000000..c247e73b39cb
--- /dev/null
+++ b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish-placeholder.stderr
@@ -0,0 +1,22 @@
+error[E0599]: no method named `default_hello` found for struct `GenericAssocMethod<{integer}>` in the current scope
+  --> $DIR/suggest-assoc-fn-call-with-turbofish-placeholder.rs:9:7
+   |
+LL | struct GenericAssocMethod<T>(T);
+   | ---------------------------- method `default_hello` not found for this struct
+...
+LL |     x.default_hello();
+   |     --^^^^^^^^^^^^^--
+   |     | |
+   |     | this is an associated function, not a method
+   |     help: use associated function syntax instead: `GenericAssocMethod::<_>::default_hello()`
+   |
+   = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
+note: the candidate is defined in an impl for the type `GenericAssocMethod<T>`
+  --> $DIR/suggest-assoc-fn-call-with-turbofish-placeholder.rs:4:5
+   |
+LL |     fn default_hello() {}
+   |     ^^^^^^^^^^^^^^^^^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0599`.
diff --git a/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish-through-deref.stderr b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish-through-deref.stderr
index 996d57731187..7c9f0b6c212e 100644
--- a/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish-through-deref.stderr
+++ b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish-through-deref.stderr
@@ -2,10 +2,10 @@ error[E0599]: no method named `hello` found for struct `RefMut<'_, HasAssocMetho
   --> $DIR/suggest-assoc-fn-call-with-turbofish-through-deref.rs:11:11
    |
 LL |     state.hello();
-   |     ------^^^^^
+   |     ------^^^^^--
    |     |     |
    |     |     this is an associated function, not a method
-   |     help: use associated function syntax instead: `HasAssocMethod::hello`
+   |     help: use associated function syntax instead: `HasAssocMethod::hello()`
    |
    = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
 note: the candidate is defined in an impl for the type `HasAssocMethod`
diff --git a/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish.fixed b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish.fixed
new file mode 100644
index 000000000000..02dd0715c801
--- /dev/null
+++ b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish.fixed
@@ -0,0 +1,26 @@
+// run-rustfix
+
+struct GenericAssocMethod<T>(T);
+
+impl<T> GenericAssocMethod<T> {
+    fn default_hello() {}
+    fn self_ty_hello(_: Self) {}
+    fn self_ty_ref_hello(_: &Self) {}
+}
+
+fn main() {
+    // Test for inferred types
+    let x = GenericAssocMethod(33);
+    GenericAssocMethod::<_>::self_ty_ref_hello(&x);
+    //~^ ERROR no method named `self_ty_ref_hello` found
+    GenericAssocMethod::<_>::self_ty_hello(x);
+    //~^ ERROR no method named `self_ty_hello` found
+    // Test for known types
+    let y = GenericAssocMethod(33i32);
+    GenericAssocMethod::<i32>::default_hello();
+    //~^ ERROR no method named `default_hello` found
+    GenericAssocMethod::<i32>::self_ty_ref_hello(&y);
+    //~^ ERROR no method named `self_ty_ref_hello` found
+    GenericAssocMethod::<i32>::self_ty_hello(y);
+    //~^ ERROR no method named `self_ty_hello` found
+}
diff --git a/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish.rs b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish.rs
index 2a829db53839..1d0ca8e780ab 100644
--- a/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish.rs
+++ b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish.rs
@@ -1,11 +1,26 @@
+// run-rustfix
+
 struct GenericAssocMethod<T>(T);
 
 impl<T> GenericAssocMethod<T> {
     fn default_hello() {}
+    fn self_ty_hello(_: Self) {}
+    fn self_ty_ref_hello(_: &Self) {}
 }
 
 fn main() {
-    let x = GenericAssocMethod(33i32);
-    x.default_hello();
+    // Test for inferred types
+    let x = GenericAssocMethod(33);
+    x.self_ty_ref_hello();
+    //~^ ERROR no method named `self_ty_ref_hello` found
+    x.self_ty_hello();
+    //~^ ERROR no method named `self_ty_hello` found
+    // Test for known types
+    let y = GenericAssocMethod(33i32);
+    y.default_hello();
     //~^ ERROR no method named `default_hello` found
+    y.self_ty_ref_hello();
+    //~^ ERROR no method named `self_ty_ref_hello` found
+    y.self_ty_hello();
+    //~^ ERROR no method named `self_ty_hello` found
 }
diff --git a/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish.stderr b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish.stderr
index 3fb418b1c0aa..92b03fc77142 100644
--- a/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish.stderr
+++ b/src/test/ui/suggestions/suggest-assoc-fn-call-with-turbofish.stderr
@@ -1,22 +1,98 @@
+error[E0599]: no method named `self_ty_ref_hello` found for struct `GenericAssocMethod<{integer}>` in the current scope
+  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:14:7
+   |
+LL | struct GenericAssocMethod<T>(T);
+   | ---------------------------- method `self_ty_ref_hello` not found for this struct
+...
+LL |     x.self_ty_ref_hello();
+   |     --^^^^^^^^^^^^^^^^^--
+   |     | |
+   |     | this is an associated function, not a method
+   |     help: use associated function syntax instead: `GenericAssocMethod::<_>::self_ty_ref_hello(&x)`
+   |
+   = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
+note: the candidate is defined in an impl for the type `GenericAssocMethod<T>`
+  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:8:5
+   |
+LL |     fn self_ty_ref_hello(_: &Self) {}
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error[E0599]: no method named `self_ty_hello` found for struct `GenericAssocMethod<{integer}>` in the current scope
+  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:16:7
+   |
+LL | struct GenericAssocMethod<T>(T);
+   | ---------------------------- method `self_ty_hello` not found for this struct
+...
+LL |     x.self_ty_hello();
+   |     --^^^^^^^^^^^^^--
+   |     | |
+   |     | this is an associated function, not a method
+   |     help: use associated function syntax instead: `GenericAssocMethod::<_>::self_ty_hello(x)`
+   |
+   = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
+note: the candidate is defined in an impl for the type `GenericAssocMethod<T>`
+  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:7:5
+   |
+LL |     fn self_ty_hello(_: Self) {}
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
+
 error[E0599]: no method named `default_hello` found for struct `GenericAssocMethod<i32>` in the current scope
-  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:9:7
+  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:20:7
    |
 LL | struct GenericAssocMethod<T>(T);
    | ---------------------------- method `default_hello` not found for this struct
 ...
-LL |     x.default_hello();
-   |     --^^^^^^^^^^^^^
+LL |     y.default_hello();
+   |     --^^^^^^^^^^^^^--
    |     | |
    |     | this is an associated function, not a method
-   |     help: use associated function syntax instead: `GenericAssocMethod::<i32>::default_hello`
+   |     help: use associated function syntax instead: `GenericAssocMethod::<i32>::default_hello()`
    |
    = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
 note: the candidate is defined in an impl for the type `GenericAssocMethod<T>`
-  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:4:5
+  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:6:5
    |
 LL |     fn default_hello() {}
    |     ^^^^^^^^^^^^^^^^^^
 
-error: aborting due to previous error
+error[E0599]: no method named `self_ty_ref_hello` found for struct `GenericAssocMethod<i32>` in the current scope
+  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:22:7
+   |
+LL | struct GenericAssocMethod<T>(T);
+   | ---------------------------- method `self_ty_ref_hello` not found for this struct
+...
+LL |     y.self_ty_ref_hello();
+   |     --^^^^^^^^^^^^^^^^^--
+   |     | |
+   |     | this is an associated function, not a method
+   |     help: use associated function syntax instead: `GenericAssocMethod::<i32>::self_ty_ref_hello(&y)`
+   |
+   = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
+note: the candidate is defined in an impl for the type `GenericAssocMethod<T>`
+  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:8:5
+   |
+LL |     fn self_ty_ref_hello(_: &Self) {}
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error[E0599]: no method named `self_ty_hello` found for struct `GenericAssocMethod<i32>` in the current scope
+  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:24:7
+   |
+LL | struct GenericAssocMethod<T>(T);
+   | ---------------------------- method `self_ty_hello` not found for this struct
+...
+LL |     y.self_ty_hello();
+   |     --^^^^^^^^^^^^^--
+   |     | |
+   |     | this is an associated function, not a method
+   |     help: use associated function syntax instead: `GenericAssocMethod::<i32>::self_ty_hello(y)`
+   |
+   = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
+note: the candidate is defined in an impl for the type `GenericAssocMethod<T>`
+  --> $DIR/suggest-assoc-fn-call-with-turbofish.rs:7:5
+   |
+LL |     fn self_ty_hello(_: Self) {}
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to 5 previous errors
 
 For more information about this error, try `rustc --explain E0599`.
diff --git a/src/test/ui/suggestions/suggest-tryinto-edition-change.rs b/src/test/ui/suggestions/suggest-tryinto-edition-change.rs
index f03b42bbe475..70c4b210d3a7 100644
--- a/src/test/ui/suggestions/suggest-tryinto-edition-change.rs
+++ b/src/test/ui/suggestions/suggest-tryinto-edition-change.rs
@@ -10,18 +10,19 @@ fn test() {
 
     let _i: i16 = TryFrom::try_from(0_i32).unwrap();
     //~^ ERROR failed to resolve: use of undeclared type
-    //~| NOTE not found in this scope
+    //~| NOTE use of undeclared type
     //~| NOTE 'std::convert::TryFrom' is included in the prelude starting in Edition 2021
     //~| NOTE 'core::convert::TryFrom' is included in the prelude starting in Edition 2021
 
     let _i: i16 = TryInto::try_into(0_i32).unwrap();
     //~^ ERROR failed to resolve: use of undeclared type
-    //~| NOTE not found in this scope
+    //~| NOTE use of undeclared type
     //~| NOTE 'std::convert::TryInto' is included in the prelude starting in Edition 2021
     //~| NOTE 'core::convert::TryInto' is included in the prelude starting in Edition 2021
 
     let _v: Vec<_> = FromIterator::from_iter(&[1]);
     //~^ ERROR failed to resolve: use of undeclared type
+    //~| NOTE use of undeclared type
     //~| NOTE 'std::iter::FromIterator' is included in the prelude starting in Edition 2021
     //~| NOTE 'core::iter::FromIterator' is included in the prelude starting in Edition 2021
 }
diff --git a/src/test/ui/suggestions/suggest-tryinto-edition-change.stderr b/src/test/ui/suggestions/suggest-tryinto-edition-change.stderr
index 86f48716b16b..3d1f2492360b 100644
--- a/src/test/ui/suggestions/suggest-tryinto-edition-change.stderr
+++ b/src/test/ui/suggestions/suggest-tryinto-edition-change.stderr
@@ -2,7 +2,7 @@ error[E0433]: failed to resolve: use of undeclared type `TryFrom`
   --> $DIR/suggest-tryinto-edition-change.rs:11:19
    |
 LL |     let _i: i16 = TryFrom::try_from(0_i32).unwrap();
-   |                   ^^^^^^^ not found in this scope
+   |                   ^^^^^^^ use of undeclared type `TryFrom`
    |
    = note: 'std::convert::TryFrom' is included in the prelude starting in Edition 2021
    = note: 'core::convert::TryFrom' is included in the prelude starting in Edition 2021
@@ -17,7 +17,7 @@ error[E0433]: failed to resolve: use of undeclared type `TryInto`
   --> $DIR/suggest-tryinto-edition-change.rs:17:19
    |
 LL |     let _i: i16 = TryInto::try_into(0_i32).unwrap();
-   |                   ^^^^^^^ not found in this scope
+   |                   ^^^^^^^ use of undeclared type `TryInto`
    |
    = note: 'std::convert::TryInto' is included in the prelude starting in Edition 2021
    = note: 'core::convert::TryInto' is included in the prelude starting in Edition 2021
@@ -32,12 +32,7 @@ error[E0433]: failed to resolve: use of undeclared type `FromIterator`
   --> $DIR/suggest-tryinto-edition-change.rs:23:22
    |
 LL |     let _v: Vec<_> = FromIterator::from_iter(&[1]);
-   |                      ^^^^^^^^^^^^
-   |
-  ::: $SRC_DIR/core/src/iter/traits/collect.rs:LL:COL
-   |
-LL | pub trait IntoIterator {
-   | ---------------------- similarly named trait `IntoIterator` defined here
+   |                      ^^^^^^^^^^^^ use of undeclared type `FromIterator`
    |
    = note: 'std::iter::FromIterator' is included in the prelude starting in Edition 2021
    = note: 'core::iter::FromIterator' is included in the prelude starting in Edition 2021
diff --git a/src/test/ui/suggestions/unnecessary_dot_for_floating_point_literal.rs b/src/test/ui/suggestions/unnecessary_dot_for_floating_point_literal.rs
new file mode 100644
index 000000000000..c1a944562683
--- /dev/null
+++ b/src/test/ui/suggestions/unnecessary_dot_for_floating_point_literal.rs
@@ -0,0 +1,6 @@
+fn main() {
+    let _: f64 = 0..10; //~ ERROR mismatched types
+    let _: f64 = 1..; //~ ERROR mismatched types
+    let _: f64 = ..10; //~ ERROR mismatched types
+    let _: f64 = std::ops::Range { start: 0, end: 1 }; //~ ERROR mismatched types
+}
diff --git a/src/test/ui/suggestions/unnecessary_dot_for_floating_point_literal.stderr b/src/test/ui/suggestions/unnecessary_dot_for_floating_point_literal.stderr
new file mode 100644
index 000000000000..773f1392ae76
--- /dev/null
+++ b/src/test/ui/suggestions/unnecessary_dot_for_floating_point_literal.stderr
@@ -0,0 +1,59 @@
+error[E0308]: mismatched types
+  --> $DIR/unnecessary_dot_for_floating_point_literal.rs:2:18
+   |
+LL |     let _: f64 = 0..10;
+   |            ---   ^^^^^ expected `f64`, found struct `std::ops::Range`
+   |            |
+   |            expected due to this
+   |
+   = note: expected type `f64`
+            found struct `std::ops::Range<{integer}>`
+help: remove the unnecessary `.` operator for a floating point literal
+   |
+LL |     let _: f64 = 0.10;
+   |                   ~
+
+error[E0308]: mismatched types
+  --> $DIR/unnecessary_dot_for_floating_point_literal.rs:3:18
+   |
+LL |     let _: f64 = 1..;
+   |            ---   ^^^ expected `f64`, found struct `RangeFrom`
+   |            |
+   |            expected due to this
+   |
+   = note: expected type `f64`
+            found struct `RangeFrom<{integer}>`
+help: remove the unnecessary `.` operator for a floating point literal
+   |
+LL |     let _: f64 = 1.;
+   |                   ~
+
+error[E0308]: mismatched types
+  --> $DIR/unnecessary_dot_for_floating_point_literal.rs:4:18
+   |
+LL |     let _: f64 = ..10;
+   |            ---   ^^^^ expected `f64`, found struct `RangeTo`
+   |            |
+   |            expected due to this
+   |
+   = note: expected type `f64`
+            found struct `RangeTo<{integer}>`
+help: remove the unnecessary `.` operator and add an integer part for a floating point literal
+   |
+LL |     let _: f64 = 0.10;
+   |                  ~~
+
+error[E0308]: mismatched types
+  --> $DIR/unnecessary_dot_for_floating_point_literal.rs:5:18
+   |
+LL |     let _: f64 = std::ops::Range { start: 0, end: 1 };
+   |            ---   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `f64`, found struct `std::ops::Range`
+   |            |
+   |            expected due to this
+   |
+   = note: expected type `f64`
+            found struct `std::ops::Range<{integer}>`
+
+error: aborting due to 4 previous errors
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/ui/target-feature/tied-features-cli.one.stderr b/src/test/ui/target-feature/tied-features-cli.one.stderr
index 0cc901eecaa2..b4b50d98192b 100644
--- a/src/test/ui/target-feature/tied-features-cli.one.stderr
+++ b/src/test/ui/target-feature/tied-features-cli.one.stderr
@@ -1,4 +1,4 @@
-error: target features paca, pacg must all be enabled or disabled together
+error: the target features paca, pacg must all be either enabled or disabled together
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/target-feature/tied-features-cli.three.stderr b/src/test/ui/target-feature/tied-features-cli.three.stderr
index 0cc901eecaa2..b4b50d98192b 100644
--- a/src/test/ui/target-feature/tied-features-cli.three.stderr
+++ b/src/test/ui/target-feature/tied-features-cli.three.stderr
@@ -1,4 +1,4 @@
-error: target features paca, pacg must all be enabled or disabled together
+error: the target features paca, pacg must all be either enabled or disabled together
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/target-feature/tied-features-cli.two.stderr b/src/test/ui/target-feature/tied-features-cli.two.stderr
index 0cc901eecaa2..b4b50d98192b 100644
--- a/src/test/ui/target-feature/tied-features-cli.two.stderr
+++ b/src/test/ui/target-feature/tied-features-cli.two.stderr
@@ -1,4 +1,4 @@
-error: target features paca, pacg must all be enabled or disabled together
+error: the target features paca, pacg must all be either enabled or disabled together
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/test-attrs/test-thread-capture.run.stdout b/src/test/ui/test-attrs/test-thread-capture.run.stdout
index c712a78afb0f..513c8cf2add0 100644
--- a/src/test/ui/test-attrs/test-thread-capture.run.stdout
+++ b/src/test/ui/test-attrs/test-thread-capture.run.stdout
@@ -10,7 +10,7 @@ fee
 fie
 foe
 fum
-thread 'main' panicked at 'explicit panic', $DIR/test-thread-capture.rs:32:5
+thread 'thready_fail' panicked at 'explicit panic', $DIR/test-thread-capture.rs:32:5
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 
 
diff --git a/src/test/ui/test-attrs/test-thread-nocapture.run.stderr b/src/test/ui/test-attrs/test-thread-nocapture.run.stderr
index 0a12a052819c..8c905d1af857 100644
--- a/src/test/ui/test-attrs/test-thread-nocapture.run.stderr
+++ b/src/test/ui/test-attrs/test-thread-nocapture.run.stderr
@@ -1,2 +1,2 @@
-thread 'main' panicked at 'explicit panic', $DIR/test-thread-nocapture.rs:32:5
+thread 'thready_fail' panicked at 'explicit panic', $DIR/test-thread-nocapture.rs:32:5
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
diff --git a/src/test/ui/track-diagnostics/track.rs b/src/test/ui/track-diagnostics/track.rs
new file mode 100644
index 000000000000..61b9137eadd9
--- /dev/null
+++ b/src/test/ui/track-diagnostics/track.rs
@@ -0,0 +1,11 @@
+// compile-flags: -Z track-diagnostics
+// error-pattern: created at
+
+// Normalize the emitted location so this doesn't need
+// updating everytime someone adds or removes a line.
+// normalize-stderr-test ".rs:\d+:\d+" -> ".rs:LL:CC"
+// normalize-stderr-test "note: rustc .+ running on .+" -> "note: rustc $$VERSION running on $$TARGET"
+
+fn main() {
+    break rust
+}
diff --git a/src/test/ui/track-diagnostics/track.stderr b/src/test/ui/track-diagnostics/track.stderr
new file mode 100644
index 000000000000..8256c1f5f0ff
--- /dev/null
+++ b/src/test/ui/track-diagnostics/track.stderr
@@ -0,0 +1,26 @@
+error[E0425]: cannot find value `rust` in this scope
+  --> $DIR/track.rs:LL:CC
+   |
+LL |     break rust
+   |           ^^^^ not found in this scope
+-Ztrack-diagnostics: created at compiler/rustc_resolve/src/late/diagnostics.rs:LL:CC
+
+error[E0268]: `break` outside of a loop or labeled block
+  --> $DIR/track.rs:LL:CC
+   |
+LL |     break rust
+   |     ^^^^^^^^^^ cannot `break` outside of a loop or labeled block
+-Ztrack-diagnostics: created at compiler/rustc_passes/src/loops.rs:LL:CC
+
+error: internal compiler error: It looks like you're trying to break rust; would you like some ICE?
+
+note: the compiler expectedly panicked. this is a feature.
+
+note: we would appreciate a joke overview: https://github.com/rust-lang/rust/issues/43162#issuecomment-320764675
+
+note: rustc $VERSION running on $TARGET
+
+error: aborting due to 3 previous errors
+
+Some errors have detailed explanations: E0268, E0425.
+For more information about an error, try `rustc --explain E0268`.
diff --git a/src/test/ui/track-diagnostics/track2.rs b/src/test/ui/track-diagnostics/track2.rs
new file mode 100644
index 000000000000..dc105c61d723
--- /dev/null
+++ b/src/test/ui/track-diagnostics/track2.rs
@@ -0,0 +1,10 @@
+// compile-flags: -Z track-diagnostics
+// error-pattern: created at
+
+// Normalize the emitted location so this doesn't need
+// updating everytime someone adds or removes a line.
+// normalize-stderr-test ".rs:\d+:\d+" -> ".rs:LL:CC"
+
+fn main() {
+    let _moved @ _from = String::from("foo");
+}
diff --git a/src/test/ui/track-diagnostics/track2.stderr b/src/test/ui/track-diagnostics/track2.stderr
new file mode 100644
index 000000000000..38a621da8164
--- /dev/null
+++ b/src/test/ui/track-diagnostics/track2.stderr
@@ -0,0 +1,13 @@
+error[E0382]: use of moved value
+  --> $DIR/track2.rs:LL:CC
+   |
+LL |     let _moved @ _from = String::from("foo");
+   |         ^^^^^^   -----   ------------------- move occurs because value has type `String`, which does not implement the `Copy` trait
+   |         |        |
+   |         |        value moved here
+   |         value used here after move
+-Ztrack-diagnostics: created at compiler/rustc_borrowck/src/borrowck_errors.rs:LL:CC
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0382`.
diff --git a/src/test/ui/track-diagnostics/track3.rs b/src/test/ui/track-diagnostics/track3.rs
new file mode 100644
index 000000000000..0699239503a9
--- /dev/null
+++ b/src/test/ui/track-diagnostics/track3.rs
@@ -0,0 +1,10 @@
+// compile-flags: -Z track-diagnostics
+// error-pattern: created at
+
+// Normalize the emitted location so this doesn't need
+// updating everytime someone adds or removes a line.
+// normalize-stderr-test ".rs:\d+:\d+" -> ".rs:LL:CC"
+
+fn main() {
+    let _unimported = Blah { field: u8 };
+}
diff --git a/src/test/ui/track-diagnostics/track3.stderr b/src/test/ui/track-diagnostics/track3.stderr
new file mode 100644
index 000000000000..dc468d7e8eeb
--- /dev/null
+++ b/src/test/ui/track-diagnostics/track3.stderr
@@ -0,0 +1,18 @@
+error[E0422]: cannot find struct, variant or union type `Blah` in this scope
+  --> $DIR/track3.rs:LL:CC
+   |
+LL |     let _unimported = Blah { field: u8 };
+   |                       ^^^^ not found in this scope
+-Ztrack-diagnostics: created at compiler/rustc_resolve/src/late/diagnostics.rs:LL:CC
+
+error[E0423]: expected value, found builtin type `u8`
+  --> $DIR/track3.rs:LL:CC
+   |
+LL |     let _unimported = Blah { field: u8 };
+   |                                     ^^ not a value
+-Ztrack-diagnostics: created at compiler/rustc_resolve/src/late/diagnostics.rs:LL:CC
+
+error: aborting due to 2 previous errors
+
+Some errors have detailed explanations: E0422, E0423.
+For more information about an error, try `rustc --explain E0422`.
diff --git a/src/test/ui/track-diagnostics/track4.rs b/src/test/ui/track-diagnostics/track4.rs
new file mode 100644
index 000000000000..35eec799bba9
--- /dev/null
+++ b/src/test/ui/track-diagnostics/track4.rs
@@ -0,0 +1,13 @@
+// compile-flags: -Z track-diagnostics
+// error-pattern: created at
+
+// Normalize the emitted location so this doesn't need
+// updating everytime someone adds or removes a line.
+// normalize-stderr-test ".rs:\d+:\d+" -> ".rs:LL:CC"
+
+pub onion {
+    Owo(u8),
+    Uwu(i8),
+}
+
+fn main() {}
diff --git a/src/test/ui/track-diagnostics/track4.stderr b/src/test/ui/track-diagnostics/track4.stderr
new file mode 100644
index 000000000000..c4668444c4bb
--- /dev/null
+++ b/src/test/ui/track-diagnostics/track4.stderr
@@ -0,0 +1,14 @@
+error: missing `struct` for struct definition
+  --> $DIR/track4.rs:LL:CC
+   |
+LL | pub onion {
+   |    ^
+-Ztrack-diagnostics: created at compiler/rustc_parse/src/parser/diagnostics.rs:LL:CC
+   |
+help: add `struct` here to parse `onion` as a public struct
+   |
+LL | pub struct onion {
+   |     ++++++
+
+error: aborting due to previous error
+
diff --git a/src/test/ui/track-diagnostics/track5.rs b/src/test/ui/track-diagnostics/track5.rs
new file mode 100644
index 000000000000..c41d9424e85a
--- /dev/null
+++ b/src/test/ui/track-diagnostics/track5.rs
@@ -0,0 +1,8 @@
+// compile-flags: -Z track-diagnostics
+// error-pattern: created at
+
+// Normalize the emitted location so this doesn't need
+// updating everytime someone adds or removes a line.
+// normalize-stderr-test ".rs:\d+:\d+" -> ".rs:LL:CC"
+
+}
diff --git a/src/test/ui/track-diagnostics/track5.stderr b/src/test/ui/track-diagnostics/track5.stderr
new file mode 100644
index 000000000000..aa54f92b6c02
--- /dev/null
+++ b/src/test/ui/track-diagnostics/track5.stderr
@@ -0,0 +1,9 @@
+error: unexpected closing delimiter: `}`
+  --> $DIR/track5.rs:LL:CC
+   |
+LL | }
+   | ^ unexpected closing delimiter
+-Ztrack-diagnostics: created at compiler/rustc_parse/src/lexer/tokentrees.rs:LL:CC
+
+error: aborting due to previous error
+
diff --git a/src/test/ui/track-diagnostics/track6.rs b/src/test/ui/track-diagnostics/track6.rs
new file mode 100644
index 000000000000..307e3101849a
--- /dev/null
+++ b/src/test/ui/track-diagnostics/track6.rs
@@ -0,0 +1,14 @@
+// compile-flags: -Z track-diagnostics
+// error-pattern: created at
+
+
+
+pub trait Foo {
+    fn bar();
+}
+
+impl <T> Foo for T {
+    default fn bar() {}
+}
+
+fn main() {}
diff --git a/src/test/ui/track-diagnostics/track6.stderr b/src/test/ui/track-diagnostics/track6.stderr
new file mode 100644
index 000000000000..1c7537633ff2
--- /dev/null
+++ b/src/test/ui/track-diagnostics/track6.stderr
@@ -0,0 +1,13 @@
+error[E0658]: specialization is unstable
+  --> $DIR/track6.rs:11:5
+   |
+LL |     default fn bar() {}
+   |     ^^^^^^^^^^^^^^^^^^^
+-Ztrack-diagnostics: created at $COMPILER_DIR/rustc_session/src/parse.rs:93:5
+   |
+   = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
+   = help: add `#![feature(specialization)]` to the crate attributes to enable
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0658`.
diff --git a/src/test/ui/traits/invalid_operator_trait.rs b/src/test/ui/traits/invalid_operator_trait.rs
new file mode 100644
index 000000000000..7ea3b0d5bac7
--- /dev/null
+++ b/src/test/ui/traits/invalid_operator_trait.rs
@@ -0,0 +1,23 @@
+#![crate_type = "lib"]
+#![feature(lang_items)]
+#![feature(no_core)]
+#![no_core]
+
+#[lang="sized"]
+pub trait Sized {
+    // Empty.
+}
+
+#[lang = "add"]
+trait Add<RHS=Self> {
+    type Output;
+
+    fn add<Y>(self, _: RHS) -> Self::Output;
+    //~^ ERROR `add` must not have any generic parameters
+}
+
+#[allow(unreachable_code)]
+fn ice(a: usize) {
+    let r = loop {};
+    r = r + a;
+}
diff --git a/src/test/ui/traits/invalid_operator_trait.stderr b/src/test/ui/traits/invalid_operator_trait.stderr
new file mode 100644
index 000000000000..8c6e3695905e
--- /dev/null
+++ b/src/test/ui/traits/invalid_operator_trait.stderr
@@ -0,0 +1,8 @@
+error: `add` must not have any generic parameters
+  --> $DIR/invalid_operator_trait.rs:15:5
+   |
+LL |     fn add<Y>(self, _: RHS) -> Self::Output;
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to previous error
+
diff --git a/src/test/ui/traits/issue-33140-hack-boundaries.stderr b/src/test/ui/traits/issue-33140-hack-boundaries.stderr
index 58286648d4fe..80a502c6335e 100644
--- a/src/test/ui/traits/issue-33140-hack-boundaries.stderr
+++ b/src/test/ui/traits/issue-33140-hack-boundaries.stderr
@@ -1,12 +1,12 @@
-error[E0119]: conflicting implementations of trait `Trait1` for type `(dyn std::marker::Send + 'static)`
+error[E0119]: conflicting implementations of trait `Trait1` for type `(dyn Send + 'static)`
   --> $DIR/issue-33140-hack-boundaries.rs:18:1
    |
 LL | impl Trait1 for dyn Send {}
    | ------------------------ first implementation here
 LL | impl Trait1 for dyn Send {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + 'static)`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn Send + 'static)`
 
-error[E0751]: found both positive and negative implementation of trait `Trait2` for type `(dyn std::marker::Send + 'static)`:
+error[E0751]: found both positive and negative implementation of trait `Trait2` for type `(dyn Send + 'static)`:
   --> $DIR/issue-33140-hack-boundaries.rs:25:1
    |
 LL | impl Trait2 for dyn Send {}
@@ -14,21 +14,21 @@ LL | impl Trait2 for dyn Send {}
 LL | impl !Trait2 for dyn Send {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^ negative implementation here
 
-error[E0119]: conflicting implementations of trait `Trait3<(dyn std::marker::Sync + 'static)>` for type `(dyn std::marker::Send + 'static)`
+error[E0119]: conflicting implementations of trait `Trait3<(dyn Sync + 'static)>` for type `(dyn Send + 'static)`
   --> $DIR/issue-33140-hack-boundaries.rs:32:1
    |
 LL | impl Trait3<dyn Sync> for dyn Send {}
    | ---------------------------------- first implementation here
 LL | impl Trait3<dyn Sync> for dyn Send {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + 'static)`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn Send + 'static)`
 
-error[E0119]: conflicting implementations of trait `Trait4a` for type `(dyn std::marker::Send + 'static)`
+error[E0119]: conflicting implementations of trait `Trait4a` for type `(dyn Send + 'static)`
   --> $DIR/issue-33140-hack-boundaries.rs:39:1
    |
 LL | impl<T: ?Sized> Trait4a for T {}
    | ----------------------------- first implementation here
 LL | impl Trait4a for dyn Send {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + 'static)`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn Send + 'static)`
 
 error[E0119]: conflicting implementations of trait `Trait4b` for type `()`
   --> $DIR/issue-33140-hack-boundaries.rs:46:1
@@ -38,42 +38,42 @@ LL | impl Trait4b for () {}
 LL | impl Trait4b for () {}
    | ^^^^^^^^^^^^^^^^^^^ conflicting implementation for `()`
 
-error[E0119]: conflicting implementations of trait `Trait4c` for type `(dyn Trait1 + std::marker::Send + 'static)`
+error[E0119]: conflicting implementations of trait `Trait4c` for type `(dyn Trait1 + Send + 'static)`
   --> $DIR/issue-33140-hack-boundaries.rs:53:1
    |
 LL | impl Trait4c for dyn Trait1 + Send {}
    | ---------------------------------- first implementation here
 LL | impl Trait4c for dyn Trait1 + Send {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn Trait1 + std::marker::Send + 'static)`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn Trait1 + Send + 'static)`
 
-error[E0119]: conflicting implementations of trait `Trait4d` for type `dyn std::marker::Send`
+error[E0119]: conflicting implementations of trait `Trait4d` for type `dyn Send`
   --> $DIR/issue-33140-hack-boundaries.rs:60:1
    |
 LL | impl<'a> Trait4d for dyn Send + 'a {}
    | ---------------------------------- first implementation here
 LL | impl<'a> Trait4d for dyn Send + 'a {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `dyn std::marker::Send`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `dyn Send`
 
-error[E0119]: conflicting implementations of trait `Trait5` for type `(dyn std::marker::Send + 'static)`
+error[E0119]: conflicting implementations of trait `Trait5` for type `(dyn Send + 'static)`
   --> $DIR/issue-33140-hack-boundaries.rs:67:1
    |
 LL | impl Trait5 for dyn Send {}
    | ------------------------ first implementation here
 LL | impl Trait5 for dyn Send where u32: Copy {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + 'static)`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn Send + 'static)`
 
 error: aborting due to 8 previous errors
 
 Some errors have detailed explanations: E0119, E0751.
 For more information about an error, try `rustc --explain E0119`.
 Future incompatibility report: Future breakage diagnostic:
-warning: conflicting implementations of trait `Trait0` for type `(dyn std::marker::Send + 'static)`: (E0119)
+warning: conflicting implementations of trait `Trait0` for type `(dyn Send + 'static)`: (E0119)
   --> $DIR/issue-33140-hack-boundaries.rs:10:1
    |
 LL | impl Trait0 for dyn Send {}
    | ------------------------ first implementation here
 LL | impl Trait0 for dyn Send {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + 'static)`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn Send + 'static)`
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #56484 <https://github.com/rust-lang/rust/issues/56484>
diff --git a/src/test/ui/traits/issue-33140.stderr b/src/test/ui/traits/issue-33140.stderr
index 392c56a282d7..d31281f7256e 100644
--- a/src/test/ui/traits/issue-33140.stderr
+++ b/src/test/ui/traits/issue-33140.stderr
@@ -1,20 +1,20 @@
-error[E0119]: conflicting implementations of trait `Trait` for type `(dyn std::marker::Send + std::marker::Sync + 'static)`
+error[E0119]: conflicting implementations of trait `Trait` for type `(dyn Send + Sync + 'static)`
   --> $DIR/issue-33140.rs:9:1
    |
 LL | impl Trait for dyn Send + Sync {
    | ------------------------------ first implementation here
 ...
 LL | impl Trait for dyn Sync + Send {
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + std::marker::Sync + 'static)`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn Send + Sync + 'static)`
 
-error[E0119]: conflicting implementations of trait `Trait2` for type `(dyn std::marker::Send + std::marker::Sync + 'static)`
+error[E0119]: conflicting implementations of trait `Trait2` for type `(dyn Send + Sync + 'static)`
   --> $DIR/issue-33140.rs:22:1
    |
 LL | impl Trait2 for dyn Send + Sync {
    | ------------------------------- first implementation here
 ...
 LL | impl Trait2 for dyn Sync + Send + Sync {
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + std::marker::Sync + 'static)`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn Send + Sync + 'static)`
 
 error[E0592]: duplicate definitions with name `abc`
   --> $DIR/issue-33140.rs:29:5
diff --git a/src/test/ui/issues/issue-7013.rs b/src/test/ui/traits/issue-7013.rs
similarity index 100%
rename from src/test/ui/issues/issue-7013.rs
rename to src/test/ui/traits/issue-7013.rs
diff --git a/src/test/ui/issues/issue-7013.stderr b/src/test/ui/traits/issue-7013.stderr
similarity index 100%
rename from src/test/ui/issues/issue-7013.stderr
rename to src/test/ui/traits/issue-7013.stderr
diff --git a/src/test/ui/traits/issue-77982.stderr b/src/test/ui/traits/issue-77982.stderr
index e210f11b3e0c..b6a04585583c 100644
--- a/src/test/ui/traits/issue-77982.stderr
+++ b/src/test/ui/traits/issue-77982.stderr
@@ -46,12 +46,7 @@ LL |     let ips: Vec<_> = (0..100_000).map(|_| u32::from(0u32.into())).collect(
    |                                            |
    |                                            required by a bound introduced by this call
    |
-   = note: multiple `impl`s satisfying `u32: From<_>` found in the following crates: `core`, `std`:
-           - impl From<Ipv4Addr> for u32;
-           - impl From<NonZeroU32> for u32;
-           - impl From<bool> for u32;
-           - impl From<char> for u32;
-           and 3 more
+   = note: cannot satisfy `u32: From<_>`
 help: try using a fully qualified path to specify the expected types
    |
 LL |     let ips: Vec<_> = (0..100_000).map(|_| u32::from(<u32 as Into<T>>::into(0u32))).collect();
diff --git a/src/test/ui/traits/issue-82830.rs b/src/test/ui/traits/issue-82830.rs
index c8289b2e30b4..37bae2e90a59 100644
--- a/src/test/ui/traits/issue-82830.rs
+++ b/src/test/ui/traits/issue-82830.rs
@@ -1,10 +1,12 @@
+// check-pass
+
 trait A<Y, N> {
     type B;
 }
 
 type MaybeBox<T> = <T as A<T, Box<T>>>::B;
 struct P {
-    t: MaybeBox<P>, //~ ERROR: overflow evaluating the requirement `P: Sized`
+    t: MaybeBox<P>,
 }
 
 impl<Y, N> A<Y, N> for P {
diff --git a/src/test/ui/traits/issue-82830.stderr b/src/test/ui/traits/issue-82830.stderr
deleted file mode 100644
index 6a597a402156..000000000000
--- a/src/test/ui/traits/issue-82830.stderr
+++ /dev/null
@@ -1,15 +0,0 @@
-error[E0275]: overflow evaluating the requirement `P: Sized`
-  --> $DIR/issue-82830.rs:7:8
-   |
-LL |     t: MaybeBox<P>,
-   |        ^^^^^^^^^^^
-   |
-note: required for `P` to implement `A<P, Box<P>>`
-  --> $DIR/issue-82830.rs:10:12
-   |
-LL | impl<Y, N> A<Y, N> for P {
-   |            ^^^^^^^     ^
-
-error: aborting due to previous error
-
-For more information about this error, try `rustc --explain E0275`.
diff --git a/src/test/ui/traits/negative-impls/eager-mono.rs b/src/test/ui/traits/negative-impls/eager-mono.rs
new file mode 100644
index 000000000000..ce770376c0b2
--- /dev/null
+++ b/src/test/ui/traits/negative-impls/eager-mono.rs
@@ -0,0 +1,12 @@
+// build-pass
+// compile-flags:-C link-dead-code=y
+
+#![feature(negative_impls)]
+
+trait Foo {
+    fn foo() {}
+}
+
+impl !Foo for () {}
+
+fn main() {}
diff --git a/src/test/ui/traits/negative-impls/pin-unsound-issue-66544-clone.stderr b/src/test/ui/traits/negative-impls/pin-unsound-issue-66544-clone.stderr
index d7039e3db6bd..a87acb1fb097 100644
--- a/src/test/ui/traits/negative-impls/pin-unsound-issue-66544-clone.stderr
+++ b/src/test/ui/traits/negative-impls/pin-unsound-issue-66544-clone.stderr
@@ -1,4 +1,4 @@
-error[E0751]: found both positive and negative implementation of trait `std::clone::Clone` for type `&mut MyType<'_>`:
+error[E0751]: found both positive and negative implementation of trait `Clone` for type `&mut MyType<'_>`:
   --> $DIR/pin-unsound-issue-66544-clone.rs:7:1
    |
 LL | impl<'a> Clone for &'a mut MyType<'a> {
diff --git a/src/test/ui/traits/negative-impls/pin-unsound-issue-66544-derefmut.stderr b/src/test/ui/traits/negative-impls/pin-unsound-issue-66544-derefmut.stderr
index a0b62a8bab68..9185e8f8430b 100644
--- a/src/test/ui/traits/negative-impls/pin-unsound-issue-66544-derefmut.stderr
+++ b/src/test/ui/traits/negative-impls/pin-unsound-issue-66544-derefmut.stderr
@@ -1,4 +1,4 @@
-error[E0751]: found both positive and negative implementation of trait `std::ops::DerefMut` for type `&MyType<'_>`:
+error[E0751]: found both positive and negative implementation of trait `DerefMut` for type `&MyType<'_>`:
   --> $DIR/pin-unsound-issue-66544-derefmut.rs:12:1
    |
 LL | impl<'a> DerefMut for &'a MyType<'a> {
diff --git a/src/test/ui/traits/object/issue-33140-traitobject-crate.stderr b/src/test/ui/traits/object/issue-33140-traitobject-crate.stderr
index 0af4df2aecb2..525401f9d69e 100644
--- a/src/test/ui/traits/object/issue-33140-traitobject-crate.stderr
+++ b/src/test/ui/traits/object/issue-33140-traitobject-crate.stderr
@@ -1,10 +1,10 @@
-warning: conflicting implementations of trait `Trait` for type `(dyn std::marker::Send + std::marker::Sync + 'static)`: (E0119)
+warning: conflicting implementations of trait `Trait` for type `(dyn Send + Sync + 'static)`: (E0119)
   --> $DIR/issue-33140-traitobject-crate.rs:86:1
    |
 LL | unsafe impl Trait for dyn (::std::marker::Send) + Sync { }
    | ------------------------------------------------------ first implementation here
 LL | unsafe impl Trait for dyn (::std::marker::Send) + Send + Sync { }
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + std::marker::Sync + 'static)`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn Send + Sync + 'static)`
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #56484 <https://github.com/rust-lang/rust/issues/56484>
@@ -14,26 +14,26 @@ note: the lint level is defined here
 LL | #![warn(order_dependent_trait_objects)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-warning: conflicting implementations of trait `Trait` for type `(dyn std::marker::Send + std::marker::Sync + 'static)`: (E0119)
+warning: conflicting implementations of trait `Trait` for type `(dyn Send + Sync + 'static)`: (E0119)
   --> $DIR/issue-33140-traitobject-crate.rs:89:1
    |
 LL | unsafe impl Trait for dyn (::std::marker::Send) + Send + Sync { }
    | ------------------------------------------------------------- first implementation here
 ...
 LL | unsafe impl Trait for dyn (::std::marker::Sync) + Send { }
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + std::marker::Sync + 'static)`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn Send + Sync + 'static)`
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #56484 <https://github.com/rust-lang/rust/issues/56484>
 
-warning: conflicting implementations of trait `Trait` for type `(dyn std::marker::Send + std::marker::Sync + 'static)`: (E0119)
+warning: conflicting implementations of trait `Trait` for type `(dyn Send + Sync + 'static)`: (E0119)
   --> $DIR/issue-33140-traitobject-crate.rs:93:1
    |
 LL | unsafe impl Trait for dyn (::std::marker::Sync) + Send { }
    | ------------------------------------------------------ first implementation here
 ...
 LL | unsafe impl Trait for dyn (::std::marker::Sync) + Send + Sync { }
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + std::marker::Sync + 'static)`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn Send + Sync + 'static)`
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #56484 <https://github.com/rust-lang/rust/issues/56484>
@@ -41,13 +41,13 @@ LL | unsafe impl Trait for dyn (::std::marker::Sync) + Send + Sync { }
 warning: 3 warnings emitted
 
 Future incompatibility report: Future breakage diagnostic:
-warning: conflicting implementations of trait `Trait` for type `(dyn std::marker::Send + std::marker::Sync + 'static)`: (E0119)
+warning: conflicting implementations of trait `Trait` for type `(dyn Send + Sync + 'static)`: (E0119)
   --> $DIR/issue-33140-traitobject-crate.rs:86:1
    |
 LL | unsafe impl Trait for dyn (::std::marker::Send) + Sync { }
    | ------------------------------------------------------ first implementation here
 LL | unsafe impl Trait for dyn (::std::marker::Send) + Send + Sync { }
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + std::marker::Sync + 'static)`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn Send + Sync + 'static)`
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #56484 <https://github.com/rust-lang/rust/issues/56484>
@@ -58,14 +58,14 @@ LL | #![warn(order_dependent_trait_objects)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 Future breakage diagnostic:
-warning: conflicting implementations of trait `Trait` for type `(dyn std::marker::Send + std::marker::Sync + 'static)`: (E0119)
+warning: conflicting implementations of trait `Trait` for type `(dyn Send + Sync + 'static)`: (E0119)
   --> $DIR/issue-33140-traitobject-crate.rs:89:1
    |
 LL | unsafe impl Trait for dyn (::std::marker::Send) + Send + Sync { }
    | ------------------------------------------------------------- first implementation here
 ...
 LL | unsafe impl Trait for dyn (::std::marker::Sync) + Send { }
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + std::marker::Sync + 'static)`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn Send + Sync + 'static)`
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #56484 <https://github.com/rust-lang/rust/issues/56484>
@@ -76,14 +76,14 @@ LL | #![warn(order_dependent_trait_objects)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 Future breakage diagnostic:
-warning: conflicting implementations of trait `Trait` for type `(dyn std::marker::Send + std::marker::Sync + 'static)`: (E0119)
+warning: conflicting implementations of trait `Trait` for type `(dyn Send + Sync + 'static)`: (E0119)
   --> $DIR/issue-33140-traitobject-crate.rs:93:1
    |
 LL | unsafe impl Trait for dyn (::std::marker::Sync) + Send { }
    | ------------------------------------------------------ first implementation here
 ...
 LL | unsafe impl Trait for dyn (::std::marker::Sync) + Send + Sync { }
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + std::marker::Sync + 'static)`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn Send + Sync + 'static)`
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #56484 <https://github.com/rust-lang/rust/issues/56484>
diff --git a/src/test/ui/traits/overlap-not-permitted-for-builtin-trait.stderr b/src/test/ui/traits/overlap-not-permitted-for-builtin-trait.stderr
index 910c5e29dac0..e24ed695dc55 100644
--- a/src/test/ui/traits/overlap-not-permitted-for-builtin-trait.stderr
+++ b/src/test/ui/traits/overlap-not-permitted-for-builtin-trait.stderr
@@ -1,4 +1,4 @@
-error[E0119]: conflicting implementations of trait `std::marker::Send` for type `MyStruct`
+error[E0119]: conflicting implementations of trait `Send` for type `MyStruct`
   --> $DIR/overlap-not-permitted-for-builtin-trait.rs:7:1
    |
 LL | impl !Send for MyStruct {}
diff --git a/src/test/ui/traits/safety-trait-impl-cc.stderr b/src/test/ui/traits/safety-trait-impl-cc.stderr
index 5a0f8d3b8cac..0b1fb30478ff 100644
--- a/src/test/ui/traits/safety-trait-impl-cc.stderr
+++ b/src/test/ui/traits/safety-trait-impl-cc.stderr
@@ -7,6 +7,12 @@ LL | |         panic!();
 LL | |     }
 LL | | }
    | |_^
+   |
+   = note: the trait `Foo` enforces invariants that the compiler can't check. Review the trait documentation and make sure this implementation upholds those invariants before adding the `unsafe` keyword
+help: add `unsafe` to this trait implementation
+   |
+LL | unsafe impl lib::Foo for Bar {
+   | ++++++
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/traits/safety-trait-impl.stderr b/src/test/ui/traits/safety-trait-impl.stderr
index fc0f6c693089..721e2b48b954 100644
--- a/src/test/ui/traits/safety-trait-impl.stderr
+++ b/src/test/ui/traits/safety-trait-impl.stderr
@@ -3,12 +3,24 @@ error[E0200]: the trait `UnsafeTrait` requires an `unsafe impl` declaration
    |
 LL | impl UnsafeTrait for u16 { }
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: the trait `UnsafeTrait` enforces invariants that the compiler can't check. Review the trait documentation and make sure this implementation upholds those invariants before adding the `unsafe` keyword
+help: add `unsafe` to this trait implementation
+   |
+LL | unsafe impl UnsafeTrait for u16 { }
+   | ++++++
 
 error[E0199]: implementing the trait `SafeTrait` is not unsafe
   --> $DIR/safety-trait-impl.rs:16:1
    |
 LL | unsafe impl SafeTrait for u32 { }
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: remove `unsafe` from this trait implementation
+   |
+LL - unsafe impl SafeTrait for u32 { }
+LL + impl SafeTrait for u32 { }
+   |
 
 error: aborting due to 2 previous errors
 
diff --git a/src/test/ui/traits/suggest-fully-qualified-closure.rs b/src/test/ui/traits/suggest-fully-qualified-closure.rs
new file mode 100644
index 000000000000..c077921c0bdd
--- /dev/null
+++ b/src/test/ui/traits/suggest-fully-qualified-closure.rs
@@ -0,0 +1,24 @@
+// check-fail
+// known-bug: #103705
+// normalize-stderr-test "\[closure@.*\]" -> "[closure@]"
+// normalize-stderr-test "\+* ~" -> "+++ ~"
+
+// The output of this currently suggests writing a closure in the qualified path.
+
+trait MyTrait<T> {
+   fn lol<F:FnOnce()>(&self, f:F) -> u16;
+}
+
+struct Qqq;
+
+impl MyTrait<u32> for Qqq{
+   fn lol<F:FnOnce()>(&self, _f:F) -> u16 { 5 }
+}
+impl MyTrait<u64> for Qqq{
+   fn lol<F:FnOnce()>(&self, _f:F) -> u16 { 6 }
+}
+
+fn main() {
+    let q = Qqq;
+    q.lol(||());
+}
diff --git a/src/test/ui/traits/suggest-fully-qualified-closure.stderr b/src/test/ui/traits/suggest-fully-qualified-closure.stderr
new file mode 100644
index 000000000000..3df623c14c3d
--- /dev/null
+++ b/src/test/ui/traits/suggest-fully-qualified-closure.stderr
@@ -0,0 +1,34 @@
+error[E0282]: type annotations needed
+  --> $DIR/suggest-fully-qualified-closure.rs:23:7
+   |
+LL |     q.lol(||());
+   |       ^^^
+   |
+help: try using a fully qualified path to specify the expected types
+   |
+LL |     <Qqq as MyTrait<T>>::lol::<[closure@]>(&q, ||());
+   |     +++ ~
+
+error[E0283]: type annotations needed
+  --> $DIR/suggest-fully-qualified-closure.rs:23:7
+   |
+LL |     q.lol(||());
+   |       ^^^
+   |
+note: multiple `impl`s satisfying `Qqq: MyTrait<_>` found
+  --> $DIR/suggest-fully-qualified-closure.rs:14:1
+   |
+LL | impl MyTrait<u32> for Qqq{
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^
+...
+LL | impl MyTrait<u64> for Qqq{
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^
+help: try using a fully qualified path to specify the expected types
+   |
+LL |     <Qqq as MyTrait<T>>::lol::<[closure@]>(&q, ||());
+   |     +++ ~
+
+error: aborting due to 2 previous errors
+
+Some errors have detailed explanations: E0282, E0283.
+For more information about an error, try `rustc --explain E0282`.
diff --git a/src/test/ui/traits/trait-upcasting/basic.rs b/src/test/ui/traits/trait-upcasting/basic.rs
index 484a222bc012..570ec5160bfe 100644
--- a/src/test/ui/traits/trait-upcasting/basic.rs
+++ b/src/test/ui/traits/trait-upcasting/basic.rs
@@ -1,7 +1,6 @@
 // run-pass
 
 #![feature(trait_upcasting)]
-#![allow(incomplete_features)]
 
 trait Foo: PartialEq<i32> + std::fmt::Debug + Send + Sync {
     fn a(&self) -> i32 {
diff --git a/src/test/ui/traits/trait-upcasting/correct-supertrait-substitution.rs b/src/test/ui/traits/trait-upcasting/correct-supertrait-substitution.rs
index 8d0a9ef0ace6..eae5cf8d58d0 100644
--- a/src/test/ui/traits/trait-upcasting/correct-supertrait-substitution.rs
+++ b/src/test/ui/traits/trait-upcasting/correct-supertrait-substitution.rs
@@ -1,6 +1,5 @@
 // run-pass
 #![feature(trait_upcasting)]
-#![allow(incomplete_features)]
 
 trait Foo<T: Default + ToString>: Bar<i32> + Bar<T> {}
 trait Bar<T: Default + ToString> {
diff --git a/src/test/ui/traits/trait-upcasting/diamond.rs b/src/test/ui/traits/trait-upcasting/diamond.rs
index e4e23c1a26e7..a4f81c464b40 100644
--- a/src/test/ui/traits/trait-upcasting/diamond.rs
+++ b/src/test/ui/traits/trait-upcasting/diamond.rs
@@ -1,7 +1,6 @@
 // run-pass
 
 #![feature(trait_upcasting)]
-#![allow(incomplete_features)]
 
 trait Foo: PartialEq<i32> + std::fmt::Debug + Send + Sync {
     fn a(&self) -> i32 {
diff --git a/src/test/ui/traits/trait-upcasting/invalid-upcast.rs b/src/test/ui/traits/trait-upcasting/invalid-upcast.rs
index 24022450406a..e634bbd5ac6f 100644
--- a/src/test/ui/traits/trait-upcasting/invalid-upcast.rs
+++ b/src/test/ui/traits/trait-upcasting/invalid-upcast.rs
@@ -1,5 +1,4 @@
 #![feature(trait_upcasting)]
-#![allow(incomplete_features)]
 
 trait Foo {
     fn a(&self) -> i32 {
diff --git a/src/test/ui/traits/trait-upcasting/invalid-upcast.stderr b/src/test/ui/traits/trait-upcasting/invalid-upcast.stderr
index b4530ed0c3a9..3aa21ee3dddf 100644
--- a/src/test/ui/traits/trait-upcasting/invalid-upcast.stderr
+++ b/src/test/ui/traits/trait-upcasting/invalid-upcast.stderr
@@ -1,5 +1,5 @@
 error[E0308]: mismatched types
-  --> $DIR/invalid-upcast.rs:54:35
+  --> $DIR/invalid-upcast.rs:53:35
    |
 LL |     let _: &dyn std::fmt::Debug = baz;
    |            --------------------   ^^^ expected trait `Debug`, found trait `Baz`
@@ -10,7 +10,7 @@ LL |     let _: &dyn std::fmt::Debug = baz;
               found reference `&dyn Baz`
 
 error[E0308]: mismatched types
-  --> $DIR/invalid-upcast.rs:56:24
+  --> $DIR/invalid-upcast.rs:55:24
    |
 LL |     let _: &dyn Send = baz;
    |            ---------   ^^^ expected trait `Send`, found trait `Baz`
@@ -21,7 +21,7 @@ LL |     let _: &dyn Send = baz;
               found reference `&dyn Baz`
 
 error[E0308]: mismatched types
-  --> $DIR/invalid-upcast.rs:58:24
+  --> $DIR/invalid-upcast.rs:57:24
    |
 LL |     let _: &dyn Sync = baz;
    |            ---------   ^^^ expected trait `Sync`, found trait `Baz`
@@ -32,7 +32,7 @@ LL |     let _: &dyn Sync = baz;
               found reference `&dyn Baz`
 
 error[E0308]: mismatched types
-  --> $DIR/invalid-upcast.rs:61:25
+  --> $DIR/invalid-upcast.rs:60:25
    |
 LL |     let bar: &dyn Bar = baz;
    |              --------   ^^^ expected trait `Bar`, found trait `Baz`
@@ -43,7 +43,7 @@ LL |     let bar: &dyn Bar = baz;
               found reference `&dyn Baz`
 
 error[E0308]: mismatched types
-  --> $DIR/invalid-upcast.rs:63:35
+  --> $DIR/invalid-upcast.rs:62:35
    |
 LL |     let _: &dyn std::fmt::Debug = bar;
    |            --------------------   ^^^ expected trait `Debug`, found trait `Bar`
@@ -54,7 +54,7 @@ LL |     let _: &dyn std::fmt::Debug = bar;
               found reference `&dyn Bar`
 
 error[E0308]: mismatched types
-  --> $DIR/invalid-upcast.rs:65:24
+  --> $DIR/invalid-upcast.rs:64:24
    |
 LL |     let _: &dyn Send = bar;
    |            ---------   ^^^ expected trait `Send`, found trait `Bar`
@@ -65,7 +65,7 @@ LL |     let _: &dyn Send = bar;
               found reference `&dyn Bar`
 
 error[E0308]: mismatched types
-  --> $DIR/invalid-upcast.rs:67:24
+  --> $DIR/invalid-upcast.rs:66:24
    |
 LL |     let _: &dyn Sync = bar;
    |            ---------   ^^^ expected trait `Sync`, found trait `Bar`
@@ -76,7 +76,7 @@ LL |     let _: &dyn Sync = bar;
               found reference `&dyn Bar`
 
 error[E0308]: mismatched types
-  --> $DIR/invalid-upcast.rs:70:25
+  --> $DIR/invalid-upcast.rs:69:25
    |
 LL |     let foo: &dyn Foo = baz;
    |              --------   ^^^ expected trait `Foo`, found trait `Baz`
@@ -87,7 +87,7 @@ LL |     let foo: &dyn Foo = baz;
               found reference `&dyn Baz`
 
 error[E0308]: mismatched types
-  --> $DIR/invalid-upcast.rs:72:35
+  --> $DIR/invalid-upcast.rs:71:35
    |
 LL |     let _: &dyn std::fmt::Debug = foo;
    |            --------------------   ^^^ expected trait `Debug`, found trait `Foo`
@@ -98,7 +98,7 @@ LL |     let _: &dyn std::fmt::Debug = foo;
               found reference `&dyn Foo`
 
 error[E0308]: mismatched types
-  --> $DIR/invalid-upcast.rs:74:24
+  --> $DIR/invalid-upcast.rs:73:24
    |
 LL |     let _: &dyn Send = foo;
    |            ---------   ^^^ expected trait `Send`, found trait `Foo`
@@ -109,7 +109,7 @@ LL |     let _: &dyn Send = foo;
               found reference `&dyn Foo`
 
 error[E0308]: mismatched types
-  --> $DIR/invalid-upcast.rs:76:24
+  --> $DIR/invalid-upcast.rs:75:24
    |
 LL |     let _: &dyn Sync = foo;
    |            ---------   ^^^ expected trait `Sync`, found trait `Foo`
@@ -120,7 +120,7 @@ LL |     let _: &dyn Sync = foo;
               found reference `&dyn Foo`
 
 error[E0308]: mismatched types
-  --> $DIR/invalid-upcast.rs:79:25
+  --> $DIR/invalid-upcast.rs:78:25
    |
 LL |     let foo: &dyn Foo = bar;
    |              --------   ^^^ expected trait `Foo`, found trait `Bar`
@@ -131,7 +131,7 @@ LL |     let foo: &dyn Foo = bar;
               found reference `&dyn Bar`
 
 error[E0308]: mismatched types
-  --> $DIR/invalid-upcast.rs:81:35
+  --> $DIR/invalid-upcast.rs:80:35
    |
 LL |     let _: &dyn std::fmt::Debug = foo;
    |            --------------------   ^^^ expected trait `Debug`, found trait `Foo`
@@ -142,7 +142,7 @@ LL |     let _: &dyn std::fmt::Debug = foo;
               found reference `&dyn Foo`
 
 error[E0308]: mismatched types
-  --> $DIR/invalid-upcast.rs:83:24
+  --> $DIR/invalid-upcast.rs:82:24
    |
 LL |     let _: &dyn Send = foo;
    |            ---------   ^^^ expected trait `Send`, found trait `Foo`
@@ -153,7 +153,7 @@ LL |     let _: &dyn Send = foo;
               found reference `&dyn Foo`
 
 error[E0308]: mismatched types
-  --> $DIR/invalid-upcast.rs:85:24
+  --> $DIR/invalid-upcast.rs:84:24
    |
 LL |     let _: &dyn Sync = foo;
    |            ---------   ^^^ expected trait `Sync`, found trait `Foo`
diff --git a/src/test/ui/traits/trait-upcasting/issue-11515-upcast-fn_mut-fn.rs b/src/test/ui/traits/trait-upcasting/issue-11515-upcast-fn_mut-fn.rs
index 6d88002540c1..b672963ae988 100644
--- a/src/test/ui/traits/trait-upcasting/issue-11515-upcast-fn_mut-fn.rs
+++ b/src/test/ui/traits/trait-upcasting/issue-11515-upcast-fn_mut-fn.rs
@@ -1,6 +1,5 @@
 // run-pass
 #![feature(trait_upcasting)]
-#![allow(incomplete_features)]
 
 struct Test {
     func: Box<dyn FnMut() + 'static>,
diff --git a/src/test/ui/traits/trait-upcasting/lifetime.rs b/src/test/ui/traits/trait-upcasting/lifetime.rs
index f029a6f081f5..9825158c2dd3 100644
--- a/src/test/ui/traits/trait-upcasting/lifetime.rs
+++ b/src/test/ui/traits/trait-upcasting/lifetime.rs
@@ -1,7 +1,6 @@
 // run-pass
 
 #![feature(trait_upcasting)]
-#![allow(incomplete_features)]
 
 trait Foo: PartialEq<i32> + std::fmt::Debug + Send + Sync {
     fn a(&self) -> i32 {
diff --git a/src/test/ui/traits/trait-upcasting/multiple-occurrence-ambiguousity.rs b/src/test/ui/traits/trait-upcasting/multiple-occurrence-ambiguousity.rs
index 6986ad621724..2e53a00a90e9 100644
--- a/src/test/ui/traits/trait-upcasting/multiple-occurrence-ambiguousity.rs
+++ b/src/test/ui/traits/trait-upcasting/multiple-occurrence-ambiguousity.rs
@@ -1,12 +1,11 @@
 // check-fail
 #![feature(trait_upcasting)]
-#![allow(incomplete_features)]
 
 trait Bar<T> {
     fn bar(&self, _: T) {}
 }
 
-trait Foo : Bar<i32> + Bar<u32> {
+trait Foo: Bar<i32> + Bar<u32> {
     fn foo(&self, _: ()) {}
 }
 
diff --git a/src/test/ui/traits/trait-upcasting/multiple-occurrence-ambiguousity.stderr b/src/test/ui/traits/trait-upcasting/multiple-occurrence-ambiguousity.stderr
index 9564813512c4..0ad18be03cdf 100644
--- a/src/test/ui/traits/trait-upcasting/multiple-occurrence-ambiguousity.stderr
+++ b/src/test/ui/traits/trait-upcasting/multiple-occurrence-ambiguousity.stderr
@@ -1,5 +1,5 @@
 error[E0308]: mismatched types
-  --> $DIR/multiple-occurrence-ambiguousity.rs:21:26
+  --> $DIR/multiple-occurrence-ambiguousity.rs:20:26
    |
 LL |     let t: &dyn Bar<_> = s;
    |            -----------   ^ expected trait `Bar`, found trait `Foo`
diff --git a/src/test/ui/traits/trait-upcasting/replace-vptr.rs b/src/test/ui/traits/trait-upcasting/replace-vptr.rs
index 1164e43611a1..9ccfc9306ac0 100644
--- a/src/test/ui/traits/trait-upcasting/replace-vptr.rs
+++ b/src/test/ui/traits/trait-upcasting/replace-vptr.rs
@@ -1,7 +1,6 @@
 // run-pass
 
 #![feature(trait_upcasting)]
-#![allow(incomplete_features)]
 
 trait A {
     fn foo_a(&self);
diff --git a/src/test/ui/traits/trait-upcasting/struct.rs b/src/test/ui/traits/trait-upcasting/struct.rs
index 0f3cb285bf4c..a3e41696956c 100644
--- a/src/test/ui/traits/trait-upcasting/struct.rs
+++ b/src/test/ui/traits/trait-upcasting/struct.rs
@@ -1,7 +1,6 @@
 // run-pass
 
 #![feature(trait_upcasting)]
-#![allow(incomplete_features)]
 
 use std::rc::Rc;
 use std::sync::Arc;
diff --git a/src/test/ui/traits/trait-upcasting/subtrait-method.rs b/src/test/ui/traits/trait-upcasting/subtrait-method.rs
index 3508e15284bf..136d15af0e8b 100644
--- a/src/test/ui/traits/trait-upcasting/subtrait-method.rs
+++ b/src/test/ui/traits/trait-upcasting/subtrait-method.rs
@@ -1,5 +1,4 @@
 #![feature(trait_upcasting)]
-#![allow(incomplete_features)]
 
 trait Foo: PartialEq<i32> + std::fmt::Debug + Send + Sync {
     fn a(&self) -> i32 {
diff --git a/src/test/ui/traits/trait-upcasting/subtrait-method.stderr b/src/test/ui/traits/trait-upcasting/subtrait-method.stderr
index af7a410f6d92..918159e845b9 100644
--- a/src/test/ui/traits/trait-upcasting/subtrait-method.stderr
+++ b/src/test/ui/traits/trait-upcasting/subtrait-method.stderr
@@ -1,64 +1,64 @@
 error[E0599]: no method named `c` found for reference `&dyn Bar` in the current scope
-  --> $DIR/subtrait-method.rs:56:9
+  --> $DIR/subtrait-method.rs:55:9
    |
 LL |     bar.c();
    |         ^ help: there is a method with a similar name: `a`
    |
    = help: items from traits can only be used if the trait is implemented and in scope
 note: `Baz` defines an item `c`, perhaps you need to implement it
-  --> $DIR/subtrait-method.rs:28:1
+  --> $DIR/subtrait-method.rs:27:1
    |
 LL | trait Baz: Bar {
    | ^^^^^^^^^^^^^^
 
 error[E0599]: no method named `b` found for reference `&dyn Foo` in the current scope
-  --> $DIR/subtrait-method.rs:60:9
+  --> $DIR/subtrait-method.rs:59:9
    |
 LL |     foo.b();
    |         ^ help: there is a method with a similar name: `a`
    |
    = help: items from traits can only be used if the trait is implemented and in scope
 note: `Bar` defines an item `b`, perhaps you need to implement it
-  --> $DIR/subtrait-method.rs:18:1
+  --> $DIR/subtrait-method.rs:17:1
    |
 LL | trait Bar: Foo {
    | ^^^^^^^^^^^^^^
 
 error[E0599]: no method named `c` found for reference `&dyn Foo` in the current scope
-  --> $DIR/subtrait-method.rs:62:9
+  --> $DIR/subtrait-method.rs:61:9
    |
 LL |     foo.c();
    |         ^ help: there is a method with a similar name: `a`
    |
    = help: items from traits can only be used if the trait is implemented and in scope
 note: `Baz` defines an item `c`, perhaps you need to implement it
-  --> $DIR/subtrait-method.rs:28:1
+  --> $DIR/subtrait-method.rs:27:1
    |
 LL | trait Baz: Bar {
    | ^^^^^^^^^^^^^^
 
 error[E0599]: no method named `b` found for reference `&dyn Foo` in the current scope
-  --> $DIR/subtrait-method.rs:66:9
+  --> $DIR/subtrait-method.rs:65:9
    |
 LL |     foo.b();
    |         ^ help: there is a method with a similar name: `a`
    |
    = help: items from traits can only be used if the trait is implemented and in scope
 note: `Bar` defines an item `b`, perhaps you need to implement it
-  --> $DIR/subtrait-method.rs:18:1
+  --> $DIR/subtrait-method.rs:17:1
    |
 LL | trait Bar: Foo {
    | ^^^^^^^^^^^^^^
 
 error[E0599]: no method named `c` found for reference `&dyn Foo` in the current scope
-  --> $DIR/subtrait-method.rs:68:9
+  --> $DIR/subtrait-method.rs:67:9
    |
 LL |     foo.c();
    |         ^ help: there is a method with a similar name: `a`
    |
    = help: items from traits can only be used if the trait is implemented and in scope
 note: `Baz` defines an item `c`, perhaps you need to implement it
-  --> $DIR/subtrait-method.rs:28:1
+  --> $DIR/subtrait-method.rs:27:1
    |
 LL | trait Baz: Bar {
    | ^^^^^^^^^^^^^^
diff --git a/src/test/ui/traits/trait-upcasting/type-checking-test-1.rs b/src/test/ui/traits/trait-upcasting/type-checking-test-1.rs
index 79ddedd41875..6bc9f4a75d33 100644
--- a/src/test/ui/traits/trait-upcasting/type-checking-test-1.rs
+++ b/src/test/ui/traits/trait-upcasting/type-checking-test-1.rs
@@ -1,5 +1,4 @@
 #![feature(trait_upcasting)]
-#![allow(incomplete_features)]
 
 trait Foo: Bar<i32> + Bar<u32> {}
 trait Bar<T> {
diff --git a/src/test/ui/traits/trait-upcasting/type-checking-test-1.stderr b/src/test/ui/traits/trait-upcasting/type-checking-test-1.stderr
index 3985372119e8..fe269d8e99bf 100644
--- a/src/test/ui/traits/trait-upcasting/type-checking-test-1.stderr
+++ b/src/test/ui/traits/trait-upcasting/type-checking-test-1.stderr
@@ -1,5 +1,5 @@
 error[E0605]: non-primitive cast: `&dyn Foo` as `&dyn Bar<_>`
-  --> $DIR/type-checking-test-1.rs:17:13
+  --> $DIR/type-checking-test-1.rs:16:13
    |
 LL |     let _ = x as &dyn Bar<_>; // Ambiguous
    |             ^^^^^^^^^^^^^^^^ invalid cast
@@ -10,7 +10,7 @@ LL |     let _ = &x as &dyn Bar<_>; // Ambiguous
    |             +
 
 error[E0277]: the trait bound `&dyn Foo: Bar<_>` is not satisfied
-  --> $DIR/type-checking-test-1.rs:17:13
+  --> $DIR/type-checking-test-1.rs:16:13
    |
 LL |     let _ = x as &dyn Bar<_>; // Ambiguous
    |             ^ the trait `Bar<_>` is not implemented for `&dyn Foo`
diff --git a/src/test/ui/traits/trait-upcasting/type-checking-test-2.rs b/src/test/ui/traits/trait-upcasting/type-checking-test-2.rs
index 32754c538037..36b11dffdb15 100644
--- a/src/test/ui/traits/trait-upcasting/type-checking-test-2.rs
+++ b/src/test/ui/traits/trait-upcasting/type-checking-test-2.rs
@@ -1,5 +1,4 @@
 #![feature(trait_upcasting)]
-#![allow(incomplete_features)]
 
 trait Foo<T>: Bar<i32> + Bar<T> {}
 trait Bar<T> {
diff --git a/src/test/ui/traits/trait-upcasting/type-checking-test-2.stderr b/src/test/ui/traits/trait-upcasting/type-checking-test-2.stderr
index 93c71f54eb53..ef007d5cb909 100644
--- a/src/test/ui/traits/trait-upcasting/type-checking-test-2.stderr
+++ b/src/test/ui/traits/trait-upcasting/type-checking-test-2.stderr
@@ -1,5 +1,5 @@
 error[E0605]: non-primitive cast: `&dyn Foo<i32>` as `&dyn Bar<u32>`
-  --> $DIR/type-checking-test-2.rs:20:13
+  --> $DIR/type-checking-test-2.rs:19:13
    |
 LL |     let _ = x as &dyn Bar<u32>; // Error
    |             ^^^^^^^^^^^^^^^^^^ invalid cast
@@ -10,7 +10,7 @@ LL |     let _ = &x as &dyn Bar<u32>; // Error
    |             +
 
 error[E0277]: the trait bound `&dyn Foo<i32>: Bar<u32>` is not satisfied
-  --> $DIR/type-checking-test-2.rs:20:13
+  --> $DIR/type-checking-test-2.rs:19:13
    |
 LL |     let _ = x as &dyn Bar<u32>; // Error
    |             ^ the trait `Bar<u32>` is not implemented for `&dyn Foo<i32>`
@@ -18,7 +18,7 @@ LL |     let _ = x as &dyn Bar<u32>; // Error
    = note: required for the cast from `&dyn Foo<i32>` to the object type `dyn Bar<u32>`
 
 error[E0605]: non-primitive cast: `&dyn Foo<u32>` as `&dyn Bar<_>`
-  --> $DIR/type-checking-test-2.rs:26:13
+  --> $DIR/type-checking-test-2.rs:25:13
    |
 LL |     let a = x as &dyn Bar<_>; // Ambiguous
    |             ^^^^^^^^^^^^^^^^ invalid cast
@@ -29,7 +29,7 @@ LL |     let a = &x as &dyn Bar<_>; // Ambiguous
    |             +
 
 error[E0277]: the trait bound `&dyn Foo<u32>: Bar<_>` is not satisfied
-  --> $DIR/type-checking-test-2.rs:26:13
+  --> $DIR/type-checking-test-2.rs:25:13
    |
 LL |     let a = x as &dyn Bar<_>; // Ambiguous
    |             ^ the trait `Bar<_>` is not implemented for `&dyn Foo<u32>`
diff --git a/src/test/ui/traits/trait-upcasting/type-checking-test-3.polonius.stderr b/src/test/ui/traits/trait-upcasting/type-checking-test-3.polonius.stderr
index e48ba709af1f..e6cb6a753998 100644
--- a/src/test/ui/traits/trait-upcasting/type-checking-test-3.polonius.stderr
+++ b/src/test/ui/traits/trait-upcasting/type-checking-test-3.polonius.stderr
@@ -1,22 +1,18 @@
 error: lifetime may not live long enough
-  --> $DIR/type-checking-test-3.rs:13:13
+  --> $DIR/type-checking-test-3.rs:11:13
    |
 LL | fn test_wrong1<'a>(x: &dyn Foo<'static>, y: &'a u32) {
    |                -- lifetime `'a` defined here
 LL |     let _ = x as &dyn Bar<'a>; // Error
    |             ^^^^^^^^^^^^^^^^^ type annotation requires that `'a` must outlive `'static`
-   |
-   = help: consider replacing `'a` with `'static`
 
 error: lifetime may not live long enough
-  --> $DIR/type-checking-test-3.rs:18:13
+  --> $DIR/type-checking-test-3.rs:16:13
    |
 LL | fn test_wrong2<'a>(x: &dyn Foo<'a>) {
    |                -- lifetime `'a` defined here
 LL |     let _ = x as &dyn Bar<'static>; // Error
    |             ^^^^^^^^^^^^^^^^^^^^^^ type annotation requires that `'a` must outlive `'static`
-   |
-   = help: consider replacing `'a` with `'static`
 
 error: aborting due to 2 previous errors
 
diff --git a/src/test/ui/traits/trait-upcasting/type-checking-test-3.rs b/src/test/ui/traits/trait-upcasting/type-checking-test-3.rs
index b3aa2279a30a..b2db3a127974 100644
--- a/src/test/ui/traits/trait-upcasting/type-checking-test-3.rs
+++ b/src/test/ui/traits/trait-upcasting/type-checking-test-3.rs
@@ -1,5 +1,4 @@
 #![feature(trait_upcasting)]
-#![allow(incomplete_features)]
 
 trait Foo<'a>: Bar<'a> {}
 trait Bar<'a> {}
@@ -10,12 +9,12 @@ fn test_correct(x: &dyn Foo<'static>) {
 
 fn test_wrong1<'a>(x: &dyn Foo<'static>, y: &'a u32) {
     let _ = x as &dyn Bar<'a>; // Error
-    //~^ ERROR lifetime may not live long enough
+                               //~^ ERROR lifetime may not live long enough
 }
 
 fn test_wrong2<'a>(x: &dyn Foo<'a>) {
     let _ = x as &dyn Bar<'static>; // Error
-    //~^ ERROR lifetime may not live long enough
+                                    //~^ ERROR lifetime may not live long enough
 }
 
 fn main() {}
diff --git a/src/test/ui/traits/trait-upcasting/type-checking-test-3.stderr b/src/test/ui/traits/trait-upcasting/type-checking-test-3.stderr
index 5ad151b50924..e6cb6a753998 100644
--- a/src/test/ui/traits/trait-upcasting/type-checking-test-3.stderr
+++ b/src/test/ui/traits/trait-upcasting/type-checking-test-3.stderr
@@ -1,5 +1,5 @@
 error: lifetime may not live long enough
-  --> $DIR/type-checking-test-3.rs:12:13
+  --> $DIR/type-checking-test-3.rs:11:13
    |
 LL | fn test_wrong1<'a>(x: &dyn Foo<'static>, y: &'a u32) {
    |                -- lifetime `'a` defined here
@@ -7,7 +7,7 @@ LL |     let _ = x as &dyn Bar<'a>; // Error
    |             ^^^^^^^^^^^^^^^^^ type annotation requires that `'a` must outlive `'static`
 
 error: lifetime may not live long enough
-  --> $DIR/type-checking-test-3.rs:17:13
+  --> $DIR/type-checking-test-3.rs:16:13
    |
 LL | fn test_wrong2<'a>(x: &dyn Foo<'a>) {
    |                -- lifetime `'a` defined here
diff --git a/src/test/ui/traits/trait-upcasting/type-checking-test-4.polonius.stderr b/src/test/ui/traits/trait-upcasting/type-checking-test-4.polonius.stderr
index a3411f40ad0f..8d506e5807ec 100644
--- a/src/test/ui/traits/trait-upcasting/type-checking-test-4.polonius.stderr
+++ b/src/test/ui/traits/trait-upcasting/type-checking-test-4.polonius.stderr
@@ -1,33 +1,52 @@
 error: lifetime may not live long enough
-  --> $DIR/type-checking-test-4.rs:17:13
+  --> $DIR/type-checking-test-4.rs:15:13
    |
 LL | fn test_wrong1<'a>(x: &dyn Foo<'static>, y: &'a u32) {
    |                -- lifetime `'a` defined here
 LL |     let _ = x as &dyn Bar<'static, 'a>; // Error
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^ type annotation requires that `'a` must outlive `'static`
-   |
-   = help: consider replacing `'a` with `'static`
 
 error: lifetime may not live long enough
-  --> $DIR/type-checking-test-4.rs:22:13
+  --> $DIR/type-checking-test-4.rs:20:13
    |
 LL | fn test_wrong2<'a>(x: &dyn Foo<'static>, y: &'a u32) {
    |                -- lifetime `'a` defined here
 LL |     let _ = x as &dyn Bar<'a, 'static>; // Error
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^ type annotation requires that `'a` must outlive `'static`
-   |
-   = help: consider replacing `'a` with `'static`
 
 error: lifetime may not live long enough
-  --> $DIR/type-checking-test-4.rs:29:5
+  --> $DIR/type-checking-test-4.rs:26:5
    |
 LL | fn test_wrong3<'a>(x: &dyn Foo<'a>) -> Option<&'static u32> {
    |                -- lifetime `'a` defined here
-...
+LL |     let y = x as &dyn Bar<'_, '_>;
 LL |     y.get_b() // ERROR
    |     ^^^^^^^^^ returning this value requires that `'a` must outlive `'static`
+
+error: lifetime may not live long enough
+  --> $DIR/type-checking-test-4.rs:31:5
    |
-   = help: consider replacing `'a` with `'static`
+LL | fn test_wrong4<'a>(x: &dyn Foo<'a>) -> Option<&'static u32> {
+   |                -- lifetime `'a` defined here
+LL |     <_ as Bar>::get_b(x) // ERROR
+   |     ^^^^^^^^^^^^^^^^^^^^ returning this value requires that `'a` must outlive `'static`
 
-error: aborting due to 3 previous errors
+error: lifetime may not live long enough
+  --> $DIR/type-checking-test-4.rs:36:5
+   |
+LL | fn test_wrong5<'a>(x: &dyn Foo<'a>) -> Option<&'static u32> {
+   |                -- lifetime `'a` defined here
+LL |     <_ as Bar<'_, '_>>::get_b(x) // ERROR
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ returning this value requires that `'a` must outlive `'static`
+
+error: lifetime may not live long enough
+  --> $DIR/type-checking-test-4.rs:44:5
+   |
+LL | fn test_wrong6<'a>(x: &dyn Foo<'a>) -> Option<&'static u32> {
+   |                -- lifetime `'a` defined here
+...
+LL |     z.get_b() // ERROR
+   |     ^^^^^^^^^ returning this value requires that `'a` must outlive `'static`
+
+error: aborting due to 6 previous errors
 
diff --git a/src/test/ui/traits/trait-upcasting/type-checking-test-4.rs b/src/test/ui/traits/trait-upcasting/type-checking-test-4.rs
index 70ccc87fc3e1..f40c48f0d125 100644
--- a/src/test/ui/traits/trait-upcasting/type-checking-test-4.rs
+++ b/src/test/ui/traits/trait-upcasting/type-checking-test-4.rs
@@ -1,5 +1,4 @@
 #![feature(trait_upcasting)]
-#![allow(incomplete_features)]
 
 trait Foo<'a>: Bar<'a, 'a> {}
 trait Bar<'a, 'b> {
@@ -14,28 +13,28 @@ fn test_correct(x: &dyn Foo<'static>) {
 
 fn test_wrong1<'a>(x: &dyn Foo<'static>, y: &'a u32) {
     let _ = x as &dyn Bar<'static, 'a>; // Error
-    //~^ ERROR lifetime may not live long enough
+                                        //~^ ERROR lifetime may not live long enough
 }
 
 fn test_wrong2<'a>(x: &dyn Foo<'static>, y: &'a u32) {
     let _ = x as &dyn Bar<'a, 'static>; // Error
-    //~^ ERROR lifetime may not live long enough
+                                        //~^ ERROR lifetime may not live long enough
 }
 
 fn test_wrong3<'a>(x: &dyn Foo<'a>) -> Option<&'static u32> {
     let y = x as &dyn Bar<'_, '_>;
     y.get_b() // ERROR
-    //~^ ERROR lifetime may not live long enough
+              //~^ ERROR lifetime may not live long enough
 }
 
 fn test_wrong4<'a>(x: &dyn Foo<'a>) -> Option<&'static u32> {
     <_ as Bar>::get_b(x) // ERROR
-    //~^ ERROR lifetime may not live long enough
+                         //~^ ERROR lifetime may not live long enough
 }
 
 fn test_wrong5<'a>(x: &dyn Foo<'a>) -> Option<&'static u32> {
     <_ as Bar<'_, '_>>::get_b(x) // ERROR
-    //~^ ERROR lifetime may not live long enough
+                                 //~^ ERROR lifetime may not live long enough
 }
 
 fn test_wrong6<'a>(x: &dyn Foo<'a>) -> Option<&'static u32> {
@@ -43,7 +42,7 @@ fn test_wrong6<'a>(x: &dyn Foo<'a>) -> Option<&'static u32> {
     y.get_b(); // ERROR
     let z = y;
     z.get_b() // ERROR
-    //~^ ERROR lifetime may not live long enough
+              //~^ ERROR lifetime may not live long enough
 }
 
 fn main() {}
diff --git a/src/test/ui/traits/trait-upcasting/type-checking-test-4.stderr b/src/test/ui/traits/trait-upcasting/type-checking-test-4.stderr
index 436129d0bee5..8d506e5807ec 100644
--- a/src/test/ui/traits/trait-upcasting/type-checking-test-4.stderr
+++ b/src/test/ui/traits/trait-upcasting/type-checking-test-4.stderr
@@ -1,5 +1,5 @@
 error: lifetime may not live long enough
-  --> $DIR/type-checking-test-4.rs:16:13
+  --> $DIR/type-checking-test-4.rs:15:13
    |
 LL | fn test_wrong1<'a>(x: &dyn Foo<'static>, y: &'a u32) {
    |                -- lifetime `'a` defined here
@@ -7,7 +7,7 @@ LL |     let _ = x as &dyn Bar<'static, 'a>; // Error
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^ type annotation requires that `'a` must outlive `'static`
 
 error: lifetime may not live long enough
-  --> $DIR/type-checking-test-4.rs:21:13
+  --> $DIR/type-checking-test-4.rs:20:13
    |
 LL | fn test_wrong2<'a>(x: &dyn Foo<'static>, y: &'a u32) {
    |                -- lifetime `'a` defined here
@@ -15,7 +15,7 @@ LL |     let _ = x as &dyn Bar<'a, 'static>; // Error
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^ type annotation requires that `'a` must outlive `'static`
 
 error: lifetime may not live long enough
-  --> $DIR/type-checking-test-4.rs:27:5
+  --> $DIR/type-checking-test-4.rs:26:5
    |
 LL | fn test_wrong3<'a>(x: &dyn Foo<'a>) -> Option<&'static u32> {
    |                -- lifetime `'a` defined here
@@ -24,7 +24,7 @@ LL |     y.get_b() // ERROR
    |     ^^^^^^^^^ returning this value requires that `'a` must outlive `'static`
 
 error: lifetime may not live long enough
-  --> $DIR/type-checking-test-4.rs:32:5
+  --> $DIR/type-checking-test-4.rs:31:5
    |
 LL | fn test_wrong4<'a>(x: &dyn Foo<'a>) -> Option<&'static u32> {
    |                -- lifetime `'a` defined here
@@ -32,7 +32,7 @@ LL |     <_ as Bar>::get_b(x) // ERROR
    |     ^^^^^^^^^^^^^^^^^^^^ returning this value requires that `'a` must outlive `'static`
 
 error: lifetime may not live long enough
-  --> $DIR/type-checking-test-4.rs:37:5
+  --> $DIR/type-checking-test-4.rs:36:5
    |
 LL | fn test_wrong5<'a>(x: &dyn Foo<'a>) -> Option<&'static u32> {
    |                -- lifetime `'a` defined here
@@ -40,7 +40,7 @@ LL |     <_ as Bar<'_, '_>>::get_b(x) // ERROR
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ returning this value requires that `'a` must outlive `'static`
 
 error: lifetime may not live long enough
-  --> $DIR/type-checking-test-4.rs:45:5
+  --> $DIR/type-checking-test-4.rs:44:5
    |
 LL | fn test_wrong6<'a>(x: &dyn Foo<'a>) -> Option<&'static u32> {
    |                -- lifetime `'a` defined here
diff --git a/src/test/ui/transmutability/arrays/issue-103783-array-length.rs b/src/test/ui/transmutability/arrays/issue-103783-array-length.rs
new file mode 100644
index 000000000000..cb36e539ed11
--- /dev/null
+++ b/src/test/ui/transmutability/arrays/issue-103783-array-length.rs
@@ -0,0 +1,24 @@
+#![crate_type = "lib"]
+#![feature(transmutability)]
+#![allow(dead_code)]
+
+mod assert {
+    use std::mem::{Assume, BikeshedIntrinsicFrom};
+    pub struct Context;
+
+    pub fn is_maybe_transmutable<Src, Dst>()
+    where
+        Dst: BikeshedIntrinsicFrom<
+            Src,
+            Context,
+            { Assume { alignment: true, lifetimes: true, safety: true, validity: true } },
+        >,
+    {
+    }
+}
+
+fn test() {
+    type NaughtyLenArray = [u32; 3.14159]; //~ ERROR mismatched types
+    type JustUnit = ();
+    assert::is_maybe_transmutable::<JustUnit, NaughtyLenArray>();
+}
diff --git a/src/test/ui/transmutability/arrays/issue-103783-array-length.stderr b/src/test/ui/transmutability/arrays/issue-103783-array-length.stderr
new file mode 100644
index 000000000000..37774c59e6cb
--- /dev/null
+++ b/src/test/ui/transmutability/arrays/issue-103783-array-length.stderr
@@ -0,0 +1,9 @@
+error[E0308]: mismatched types
+  --> $DIR/issue-103783-array-length.rs:21:34
+   |
+LL |     type NaughtyLenArray = [u32; 3.14159];
+   |                                  ^^^^^^^ expected `usize`, found floating-point number
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/ui/transmutability/enums/should_order_correctly.rs b/src/test/ui/transmutability/enums/should_order_correctly.rs
index b753cf0e62d5..1335cc9d2b17 100644
--- a/src/test/ui/transmutability/enums/should_order_correctly.rs
+++ b/src/test/ui/transmutability/enums/should_order_correctly.rs
@@ -2,7 +2,6 @@
 //! The payloads of an enum variant should be ordered after its tag.
 
 #![crate_type = "lib"]
-#![feature(arbitrary_enum_discriminant)]
 #![feature(transmutability)]
 #![allow(dead_code)]
 
diff --git a/src/test/ui/transmutability/enums/should_respect_endianness.rs b/src/test/ui/transmutability/enums/should_respect_endianness.rs
index 19ff69005003..f3567b405f40 100644
--- a/src/test/ui/transmutability/enums/should_respect_endianness.rs
+++ b/src/test/ui/transmutability/enums/should_respect_endianness.rs
@@ -2,7 +2,6 @@
 //! an enum with a multi-byte tag.
 
 #![crate_type = "lib"]
-#![feature(arbitrary_enum_discriminant)]
 #![feature(transmutability)]
 #![allow(dead_code)]
 
diff --git a/src/test/ui/transmutability/enums/should_respect_endianness.stderr b/src/test/ui/transmutability/enums/should_respect_endianness.stderr
index fcb70813bd96..0845a5edf32e 100644
--- a/src/test/ui/transmutability/enums/should_respect_endianness.stderr
+++ b/src/test/ui/transmutability/enums/should_respect_endianness.stderr
@@ -1,12 +1,12 @@
 error[E0277]: `Src` cannot be safely transmuted into `Unexpected` in the defining scope of `assert::Context`.
-  --> $DIR/should_respect_endianness.rs:37:36
+  --> $DIR/should_respect_endianness.rs:36:36
    |
 LL |     assert::is_transmutable::<Src, Unexpected>();
    |                                    ^^^^^^^^^^ `Src` cannot be safely transmuted into `Unexpected` in the defining scope of `assert::Context`.
    |
    = help: the trait `BikeshedIntrinsicFrom<Src, assert::Context, Assume { alignment: true, lifetimes: true, safety: true, validity: true }>` is not implemented for `Unexpected`
 note: required by a bound in `is_transmutable`
-  --> $DIR/should_respect_endianness.rs:15:14
+  --> $DIR/should_respect_endianness.rs:14:14
    |
 LL |       pub fn is_transmutable<Src, Dst>()
    |              --------------- required by a bound in this
diff --git a/src/test/ui/transmute/transmute-padding-ice.rs b/src/test/ui/transmute/transmute-padding-ice.rs
new file mode 100644
index 000000000000..a1be7075a8a0
--- /dev/null
+++ b/src/test/ui/transmute/transmute-padding-ice.rs
@@ -0,0 +1,29 @@
+#![crate_type = "lib"]
+#![feature(transmutability)]
+#![allow(dead_code)]
+
+mod assert {
+    use std::mem::{Assume, BikeshedIntrinsicFrom};
+    pub struct Context;
+
+    pub fn is_maybe_transmutable<Src, Dst>()
+    where
+        Dst: BikeshedIntrinsicFrom<
+            Src,
+            Context,
+            { Assume { alignment: true, lifetimes: true, safety: true, validity: true } },
+        >,
+    {
+    }
+}
+
+fn test() {
+    #[repr(C, align(2))]
+    struct A(u8, u8);
+
+    #[repr(C)]
+    struct B(u8, u8);
+
+    assert::is_maybe_transmutable::<B, A>();
+    //~^ ERROR cannot be safely transmuted
+}
diff --git a/src/test/ui/transmute/transmute-padding-ice.stderr b/src/test/ui/transmute/transmute-padding-ice.stderr
new file mode 100644
index 000000000000..c9233890f7aa
--- /dev/null
+++ b/src/test/ui/transmute/transmute-padding-ice.stderr
@@ -0,0 +1,24 @@
+error[E0277]: `B` cannot be safely transmuted into `A` in the defining scope of `assert::Context`.
+  --> $DIR/transmute-padding-ice.rs:27:40
+   |
+LL |     assert::is_maybe_transmutable::<B, A>();
+   |                                        ^ `B` cannot be safely transmuted into `A` in the defining scope of `assert::Context`.
+   |
+   = help: the trait `BikeshedIntrinsicFrom<B, assert::Context, Assume { alignment: true, lifetimes: true, safety: true, validity: true }>` is not implemented for `A`
+note: required by a bound in `is_maybe_transmutable`
+  --> $DIR/transmute-padding-ice.rs:11:14
+   |
+LL |       pub fn is_maybe_transmutable<Src, Dst>()
+   |              --------------------- required by a bound in this
+LL |       where
+LL |           Dst: BikeshedIntrinsicFrom<
+   |  ______________^
+LL | |             Src,
+LL | |             Context,
+LL | |             { Assume { alignment: true, lifetimes: true, safety: true, validity: true } },
+LL | |         >,
+   | |_________^ required by this bound in `is_maybe_transmutable`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0277`.
diff --git a/src/test/ui/type-alias-enum-variants/self-in-enum-definition.stderr b/src/test/ui/type-alias-enum-variants/self-in-enum-definition.stderr
index 4775e68820b5..576fc6a4f8d5 100644
--- a/src/test/ui/type-alias-enum-variants/self-in-enum-definition.stderr
+++ b/src/test/ui/type-alias-enum-variants/self-in-enum-definition.stderr
@@ -12,6 +12,46 @@ LL |     V3 = Self::V1 {} as u8 + 2,
 note: ...which requires const-evaluating + checking `Alpha::V3::{constant#0}`...
   --> $DIR/self-in-enum-definition.rs:5:10
    |
+LL |     V3 = Self::V1 {} as u8 + 2,
+   |          ^^^^^^^^^^^^^^^^^^^^^
+note: ...which requires caching mir of `Alpha::V3::{constant#0}` for CTFE...
+  --> $DIR/self-in-enum-definition.rs:5:10
+   |
+LL |     V3 = Self::V1 {} as u8 + 2,
+   |          ^^^^^^^^^^^^^^^^^^^^^
+note: ...which requires elaborating drops for `Alpha::V3::{constant#0}`...
+  --> $DIR/self-in-enum-definition.rs:5:10
+   |
+LL |     V3 = Self::V1 {} as u8 + 2,
+   |          ^^^^^^^^^^^^^^^^^^^^^
+note: ...which requires borrow-checking `Alpha::V3::{constant#0}`...
+  --> $DIR/self-in-enum-definition.rs:5:10
+   |
+LL |     V3 = Self::V1 {} as u8 + 2,
+   |          ^^^^^^^^^^^^^^^^^^^^^
+note: ...which requires processing MIR for `Alpha::V3::{constant#0}`...
+  --> $DIR/self-in-enum-definition.rs:5:10
+   |
+LL |     V3 = Self::V1 {} as u8 + 2,
+   |          ^^^^^^^^^^^^^^^^^^^^^
+note: ...which requires const checking `Alpha::V3::{constant#0}`...
+  --> $DIR/self-in-enum-definition.rs:5:10
+   |
+LL |     V3 = Self::V1 {} as u8 + 2,
+   |          ^^^^^^^^^^^^^^^^^^^^^
+note: ...which requires preparing `Alpha::V3::{constant#0}` for borrow checking...
+  --> $DIR/self-in-enum-definition.rs:5:10
+   |
+LL |     V3 = Self::V1 {} as u8 + 2,
+   |          ^^^^^^^^^^^^^^^^^^^^^
+note: ...which requires unsafety-checking `Alpha::V3::{constant#0}`...
+  --> $DIR/self-in-enum-definition.rs:5:10
+   |
+LL |     V3 = Self::V1 {} as u8 + 2,
+   |          ^^^^^^^^^^^^^^^^^^^^^
+note: ...which requires building MIR for `Alpha::V3::{constant#0}`...
+  --> $DIR/self-in-enum-definition.rs:5:10
+   |
 LL |     V3 = Self::V1 {} as u8 + 2,
    |          ^^^^^^^^^^^^^^^^^^^^^
    = note: ...which requires computing layout of `Alpha`...
diff --git a/src/test/ui/type-alias-impl-trait/issue-101750.rs b/src/test/ui/type-alias-impl-trait/issue-101750.rs
new file mode 100644
index 000000000000..f564f4fa702c
--- /dev/null
+++ b/src/test/ui/type-alias-impl-trait/issue-101750.rs
@@ -0,0 +1,37 @@
+#![feature(type_alias_impl_trait)]
+
+// check-pass
+
+trait Trait {}
+
+type TAIT = impl Trait;
+
+struct Concrete;
+impl Trait for Concrete {}
+
+fn tait() -> TAIT {
+    Concrete
+}
+
+trait OuterTrait {
+    type Item;
+}
+struct Dummy<T> {
+    t: T,
+}
+impl<T> OuterTrait for Dummy<T> {
+    type Item = T;
+}
+
+fn tait_and_impl_trait() -> impl OuterTrait<Item = (TAIT, impl Trait)> {
+    Dummy {
+        t: (tait(), Concrete),
+    }
+}
+
+fn tait_and_dyn_trait() -> impl OuterTrait<Item = (TAIT, Box<dyn Trait>)> {
+    let b: Box<dyn Trait> = Box::new(Concrete);
+    Dummy { t: (tait(), b) }
+}
+
+fn main() {}
diff --git a/src/test/ui/type-alias-impl-trait/issue-57611-trait-alias.rs b/src/test/ui/type-alias-impl-trait/issue-57611-trait-alias.rs
index 067ed7ea1e58..cad3e0f66774 100644
--- a/src/test/ui/type-alias-impl-trait/issue-57611-trait-alias.rs
+++ b/src/test/ui/type-alias-impl-trait/issue-57611-trait-alias.rs
@@ -1,7 +1,6 @@
+// check-pass
 // Regression test for issue #57611
 // Ensures that we don't ICE
-// FIXME: This should compile, but it currently doesn't
-// known-bug: unknown
 
 #![feature(trait_alias)]
 #![feature(type_alias_impl_trait)]
diff --git a/src/test/ui/type-alias-impl-trait/issue-57611-trait-alias.stderr b/src/test/ui/type-alias-impl-trait/issue-57611-trait-alias.stderr
deleted file mode 100644
index 6344f114a913..000000000000
--- a/src/test/ui/type-alias-impl-trait/issue-57611-trait-alias.stderr
+++ /dev/null
@@ -1,26 +0,0 @@
-error[E0308]: mismatched types
-  --> $DIR/issue-57611-trait-alias.rs:21:9
-   |
-LL |         |x| x
-   |         ^^^^^ one type is more general than the other
-   |
-   = note: expected trait `for<'a> Fn<(&'a X,)>`
-              found trait `Fn<(&X,)>`
-note: this closure does not fulfill the lifetime requirements
-  --> $DIR/issue-57611-trait-alias.rs:21:9
-   |
-LL |         |x| x
-   |         ^^^
-
-error: implementation of `FnOnce` is not general enough
-  --> $DIR/issue-57611-trait-alias.rs:21:9
-   |
-LL |         |x| x
-   |         ^^^^^ implementation of `FnOnce` is not general enough
-   |
-   = note: closure with signature `fn(&'2 X) -> &X` must implement `FnOnce<(&'1 X,)>`, for any lifetime `'1`...
-   = note: ...but it actually implements `FnOnce<(&'2 X,)>`, for some specific lifetime `'2`
-
-error: aborting due to 2 previous errors
-
-For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/ui/type/issue-103271.rs b/src/test/ui/type/issue-103271.rs
new file mode 100644
index 000000000000..bd3254af3df7
--- /dev/null
+++ b/src/test/ui/type/issue-103271.rs
@@ -0,0 +1,10 @@
+fn main() {
+    let iter_fun = <&[u32]>::iter;
+    //~^ ERROR no function or associated item named `iter` found for reference `&[u32]` in the current scope [E0599]
+    //~| function or associated item not found in `&[u32]`
+    //~| HELP the function `iter` is implemented on `[u32]`
+    for item in iter_fun(&[1,1]) {
+        let x: &u32 = item;
+        assert_eq!(x, &1);
+    }
+}
diff --git a/src/test/ui/type/issue-103271.stderr b/src/test/ui/type/issue-103271.stderr
new file mode 100644
index 000000000000..02a59d4b99c4
--- /dev/null
+++ b/src/test/ui/type/issue-103271.stderr
@@ -0,0 +1,14 @@
+error[E0599]: no function or associated item named `iter` found for reference `&[u32]` in the current scope
+  --> $DIR/issue-103271.rs:2:30
+   |
+LL |     let iter_fun = <&[u32]>::iter;
+   |                              ^^^^ function or associated item not found in `&[u32]`
+   |
+help: the function `iter` is implemented on `[u32]`
+   |
+LL |     let iter_fun = <[u32]>::iter;
+   |                     ~~~~~
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0599`.
diff --git a/src/test/ui/type/issue-94187-verbose-type-name.rs b/src/test/ui/type/issue-94187-verbose-type-name.rs
new file mode 100644
index 000000000000..3713a32eb118
--- /dev/null
+++ b/src/test/ui/type/issue-94187-verbose-type-name.rs
@@ -0,0 +1,16 @@
+// Check to insure that the output of `std::any::type_name` does not change based on `-Zverbose`
+// run-pass
+// edition: 2018
+// revisions: normal verbose
+// [verbose]compile-flags:-Zverbose
+
+use std::any::type_name;
+
+fn main() {
+    assert_eq!(type_name::<[u32; 0]>(), "[u32; 0]");
+
+    struct Wrapper<const VALUE: usize>;
+    assert_eq!(type_name::<Wrapper<0>>(), "issue_94187_verbose_type_name::main::Wrapper<0>");
+
+    assert_eq!(type_name::<dyn Fn(u32) -> u32>(), "dyn core::ops::function::Fn(u32) -> u32");
+}
diff --git a/src/test/ui/typeck/issue-103899.rs b/src/test/ui/typeck/issue-103899.rs
new file mode 100644
index 000000000000..9d5341dab42f
--- /dev/null
+++ b/src/test/ui/typeck/issue-103899.rs
@@ -0,0 +1,33 @@
+// check-fail
+// failure-status: 101
+// normalize-stderr-test "note: .*" -> ""
+// normalize-stderr-test "thread 'rustc' .*" -> ""
+// normalize-stderr-test " .*\n" -> ""
+// normalize-stderr-test "  .*\n" -> ""
+// known-bug: #103899
+
+trait BaseWithAssoc {
+    type Assoc;
+}
+
+trait WrapperWithAssoc {
+    type BaseAssoc: BaseWithAssoc;
+}
+
+struct Wrapper<B> {
+    inner: B,
+}
+
+struct ProjectToBase<T: BaseWithAssoc> {
+    data_type_h: T::Assoc,
+}
+
+struct DoubleProject<L: WrapperWithAssoc> {
+    buffer: Wrapper<ProjectToBase<L::BaseAssoc>>,
+}
+
+fn trigger<L: WrapperWithAssoc<BaseAssoc = ()>>() -> DoubleProject<L> {
+    loop {}
+}
+
+fn main() {}
diff --git a/src/test/ui/typeck/issue-103899.stderr b/src/test/ui/typeck/issue-103899.stderr
new file mode 100644
index 000000000000..836c6ee486f5
--- /dev/null
+++ b/src/test/ui/typeck/issue-103899.stderr
@@ -0,0 +1,12 @@
+
+stack
+error:
+
+
+
+
+
+
+
+
+query#0#1end
\ No newline at end of file
diff --git a/src/test/ui/issues/issue-10969.rs b/src/test/ui/typeck/issue-10969.rs
similarity index 100%
rename from src/test/ui/issues/issue-10969.rs
rename to src/test/ui/typeck/issue-10969.rs
diff --git a/src/test/ui/issues/issue-10969.stderr b/src/test/ui/typeck/issue-10969.stderr
similarity index 100%
rename from src/test/ui/issues/issue-10969.stderr
rename to src/test/ui/typeck/issue-10969.stderr
diff --git a/src/test/ui/issues/issue-50687-ice-on-borrow.rs b/src/test/ui/typeck/issue-50687-ice-on-borrow.rs
similarity index 100%
rename from src/test/ui/issues/issue-50687-ice-on-borrow.rs
rename to src/test/ui/typeck/issue-50687-ice-on-borrow.rs
diff --git a/src/test/ui/issues/issue-50687-ice-on-borrow.stderr b/src/test/ui/typeck/issue-50687-ice-on-borrow.stderr
similarity index 100%
rename from src/test/ui/issues/issue-50687-ice-on-borrow.stderr
rename to src/test/ui/typeck/issue-50687-ice-on-borrow.stderr
diff --git a/src/test/ui/typeck/issue-83693.stderr b/src/test/ui/typeck/issue-83693.stderr
index 0d8bbf1ce98c..1e45c2d35dfd 100644
--- a/src/test/ui/typeck/issue-83693.stderr
+++ b/src/test/ui/typeck/issue-83693.stderr
@@ -6,8 +6,8 @@ LL | impl F {
    |
   ::: $SRC_DIR/core/src/ops/function.rs:LL:COL
    |
-LL | pub trait Fn<Args>: FnMut<Args> {
-   | ------------------------------- similarly named trait `Fn` defined here
+LL | pub trait Fn<Args: Tuple>: FnMut<Args> {
+   | -------------------------------------- similarly named trait `Fn` defined here
 
 error[E0412]: cannot find type `TestResult` in this scope
   --> $DIR/issue-83693.rs:9:22
diff --git a/src/test/ui/unboxed-closures/non-tupled-arg-mismatch.rs b/src/test/ui/unboxed-closures/non-tupled-arg-mismatch.rs
index 925463d6deed..d2e486002272 100644
--- a/src/test/ui/unboxed-closures/non-tupled-arg-mismatch.rs
+++ b/src/test/ui/unboxed-closures/non-tupled-arg-mismatch.rs
@@ -1,8 +1,8 @@
 #![feature(unboxed_closures)]
 
 fn a<F: Fn<usize>>(f: F) {}
+//~^ ERROR type parameter to bare `Fn` trait must be a tuple
 
 fn main() {
     a(|_: usize| {});
-    //~^ ERROR mismatched types
 }
diff --git a/src/test/ui/unboxed-closures/non-tupled-arg-mismatch.stderr b/src/test/ui/unboxed-closures/non-tupled-arg-mismatch.stderr
index 9a24fb8c2bee..1c18eb0fc490 100644
--- a/src/test/ui/unboxed-closures/non-tupled-arg-mismatch.stderr
+++ b/src/test/ui/unboxed-closures/non-tupled-arg-mismatch.stderr
@@ -1,17 +1,15 @@
-error[E0308]: mismatched types
-  --> $DIR/non-tupled-arg-mismatch.rs:6:5
-   |
-LL |     a(|_: usize| {});
-   |     ^ types differ
-   |
-   = note: expected trait `Fn<usize>`
-              found trait `Fn<(usize,)>`
-note: required by a bound in `a`
+error[E0059]: type parameter to bare `Fn` trait must be a tuple
   --> $DIR/non-tupled-arg-mismatch.rs:3:9
    |
 LL | fn a<F: Fn<usize>>(f: F) {}
-   |         ^^^^^^^^^ required by this bound in `a`
+   |         ^^^^^^^^^ the trait `Tuple` is not implemented for `usize`
+   |
+note: required by a bound in `Fn`
+  --> $SRC_DIR/core/src/ops/function.rs:LL:COL
+   |
+LL | pub trait Fn<Args: Tuple>: FnMut<Args> {
+   |                    ^^^^^ required by this bound in `Fn`
 
 error: aborting due to previous error
 
-For more information about this error, try `rustc --explain E0308`.
+For more information about this error, try `rustc --explain E0059`.
diff --git a/src/test/ui/unboxed-closures/unboxed-closure-illegal-move.rs b/src/test/ui/unboxed-closures/unboxed-closure-illegal-move.rs
index ed8d72114613..7377359b6b0c 100644
--- a/src/test/ui/unboxed-closures/unboxed-closure-illegal-move.rs
+++ b/src/test/ui/unboxed-closures/unboxed-closure-illegal-move.rs
@@ -1,12 +1,12 @@
-#![feature(unboxed_closures)]
+#![feature(unboxed_closures, tuple_trait)]
 
 // Tests that we can't move out of an unboxed closure environment
 // if the upvar is captured by ref or the closure takes self by
 // reference.
 
-fn to_fn<A,F:Fn<A>>(f: F) -> F { f }
-fn to_fn_mut<A,F:FnMut<A>>(f: F) -> F { f }
-fn to_fn_once<A,F:FnOnce<A>>(f: F) -> F { f }
+fn to_fn<A:std::marker::Tuple,F:Fn<A>>(f: F) -> F { f }
+fn to_fn_mut<A:std::marker::Tuple,F:FnMut<A>>(f: F) -> F { f }
+fn to_fn_once<A:std::marker::Tuple,F:FnOnce<A>>(f: F) -> F { f }
 
 fn main() {
     // By-ref cases
diff --git a/src/test/ui/unboxed-closures/unboxed-closures-mutate-upvar.rs b/src/test/ui/unboxed-closures/unboxed-closures-mutate-upvar.rs
index 57e6d30658ce..c57312b43874 100644
--- a/src/test/ui/unboxed-closures/unboxed-closures-mutate-upvar.rs
+++ b/src/test/ui/unboxed-closures/unboxed-closures-mutate-upvar.rs
@@ -2,12 +2,12 @@
 // as `mut` through a closure. Also test that we CAN mutate a moved copy,
 // unless this is a `Fn` closure. Issue #16749.
 
-#![feature(unboxed_closures)]
+#![feature(unboxed_closures, tuple_trait)]
 
 use std::mem;
 
-fn to_fn<A,F:Fn<A>>(f: F) -> F { f }
-fn to_fn_mut<A,F:FnMut<A>>(f: F) -> F { f }
+fn to_fn<A:std::marker::Tuple,F:Fn<A>>(f: F) -> F { f }
+fn to_fn_mut<A:std::marker::Tuple,F:FnMut<A>>(f: F) -> F { f }
 
 fn a() {
     let n = 0;
diff --git a/src/test/ui/unboxed-closures/unboxed-closures-mutate-upvar.stderr b/src/test/ui/unboxed-closures/unboxed-closures-mutate-upvar.stderr
index d6e74b5b8b91..26f97b51913d 100644
--- a/src/test/ui/unboxed-closures/unboxed-closures-mutate-upvar.stderr
+++ b/src/test/ui/unboxed-closures/unboxed-closures-mutate-upvar.stderr
@@ -28,8 +28,8 @@ LL |         n += 1;
 error[E0594]: cannot assign to `n`, as it is a captured variable in a `Fn` closure
   --> $DIR/unboxed-closures-mutate-upvar.rs:53:9
    |
-LL | fn to_fn<A,F:Fn<A>>(f: F) -> F { f }
-   |                        - change this to accept `FnMut` instead of `Fn`
+LL | fn to_fn<A:std::marker::Tuple,F:Fn<A>>(f: F) -> F { f }
+   |                                           - change this to accept `FnMut` instead of `Fn`
 ...
 LL |     let mut f = to_fn(move || {
    |                 ----- ------- in this closure
diff --git a/src/test/ui/unboxed-closures/unboxed-closures-static-call-wrong-trait.rs b/src/test/ui/unboxed-closures/unboxed-closures-static-call-wrong-trait.rs
index 0e727b11cd21..7289d9322d05 100644
--- a/src/test/ui/unboxed-closures/unboxed-closures-static-call-wrong-trait.rs
+++ b/src/test/ui/unboxed-closures/unboxed-closures-static-call-wrong-trait.rs
@@ -1,6 +1,6 @@
-#![feature(unboxed_closures)]
+#![feature(unboxed_closures, tuple_trait)]
 
-fn to_fn_mut<A,F:FnMut<A>>(f: F) -> F { f }
+fn to_fn_mut<A:std::marker::Tuple,F:FnMut<A>>(f: F) -> F { f }
 
 fn main() {
     let mut_ = to_fn_mut(|x| x);
diff --git a/src/test/ui/underscore-ident-matcher.stderr b/src/test/ui/underscore-ident-matcher.stderr
index 241c3d3d8ce6..b0e4d88f6718 100644
--- a/src/test/ui/underscore-ident-matcher.stderr
+++ b/src/test/ui/underscore-ident-matcher.stderr
@@ -6,6 +6,12 @@ LL | macro_rules! identity {
 ...
 LL |     let identity!(_) = 10;
    |                   ^ no rules expected this token in macro call
+   |
+note: while trying to match meta-variable `$i:ident`
+  --> $DIR/underscore-ident-matcher.rs:2:6
+   |
+LL |     ($i: ident) => (
+   |      ^^^^^^^^^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/unsafe/unsafe-not-inherited.rs b/src/test/ui/unsafe/unsafe-not-inherited.rs
new file mode 100644
index 000000000000..6d797caa0f94
--- /dev/null
+++ b/src/test/ui/unsafe/unsafe-not-inherited.rs
@@ -0,0 +1,26 @@
+#![allow(unused, dead_code)]
+
+static mut FOO: u64 = 0;
+
+fn static_mod() {
+    unsafe {static BAR: u64 = FOO;}
+    //~^ ERROR: use of mutable static is unsafe
+    //~| NOTE: use of mutable static
+    //~| NOTE: mutable statics can be mutated by multiple threads
+    //~| NOTE: items do not inherit unsafety
+}
+
+unsafe fn unsafe_call() {}
+fn foo() {
+    unsafe {
+    //~^ NOTE: items do not inherit unsafety
+        fn bar() {
+            unsafe_call();
+            //~^ ERROR: call to unsafe function
+            //~| NOTE: call to unsafe function
+            //~| NOTE: consult the function's documentation
+        }
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/unsafe/unsafe-not-inherited.stderr b/src/test/ui/unsafe/unsafe-not-inherited.stderr
new file mode 100644
index 000000000000..3bc5ca5c9d15
--- /dev/null
+++ b/src/test/ui/unsafe/unsafe-not-inherited.stderr
@@ -0,0 +1,24 @@
+error[E0133]: use of mutable static is unsafe and requires unsafe function or block
+  --> $DIR/unsafe-not-inherited.rs:6:31
+   |
+LL |     unsafe {static BAR: u64 = FOO;}
+   |     ------                    ^^^ use of mutable static
+   |     |
+   |     items do not inherit unsafety from separate enclosing items
+   |
+   = note: mutable statics can be mutated by multiple threads: aliasing violations or data races will cause undefined behavior
+
+error[E0133]: call to unsafe function is unsafe and requires unsafe function or block
+  --> $DIR/unsafe-not-inherited.rs:18:13
+   |
+LL |     unsafe {
+   |     ------ items do not inherit unsafety from separate enclosing items
+...
+LL |             unsafe_call();
+   |             ^^^^^^^^^^^^^ call to unsafe function
+   |
+   = note: consult the function's documentation for information on how to avoid undefined behavior
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0133`.
diff --git a/src/test/ui/use/use-crate-self.rs b/src/test/ui/use/use-crate-self.rs
new file mode 100644
index 000000000000..65ab948147cd
--- /dev/null
+++ b/src/test/ui/use/use-crate-self.rs
@@ -0,0 +1,4 @@
+use crate::{self};
+        //~^ ERROR crate root imports need to be explicitly named: `use crate as name;`
+
+fn main() {}
diff --git a/src/test/ui/use/use-crate-self.stderr b/src/test/ui/use/use-crate-self.stderr
new file mode 100644
index 000000000000..dd4036bfff47
--- /dev/null
+++ b/src/test/ui/use/use-crate-self.stderr
@@ -0,0 +1,8 @@
+error: crate root imports need to be explicitly named: `use crate as name;`
+  --> $DIR/use-crate-self.rs:1:13
+   |
+LL | use crate::{self};
+   |             ^^^^
+
+error: aborting due to previous error
+
diff --git a/src/test/ui/weird-exprs.rs b/src/test/ui/weird-exprs.rs
index 4066bcf3badd..d65703ef5cae 100644
--- a/src/test/ui/weird-exprs.rs
+++ b/src/test/ui/weird-exprs.rs
@@ -8,6 +8,7 @@
 #![allow(unreachable_code)]
 #![allow(unused_braces, unused_must_use, unused_parens)]
 #![allow(uncommon_codepoints, confusable_idents)]
+#![allow(unreachable_patterns)]
 
 #![recursion_limit = "256"]
 
@@ -194,6 +195,15 @@ fn bathroom_stall() {
     assert_eq!(i, 13);
 }
 
+fn closure_matching() {
+    let x = |_| Some(1);
+    let (|x| x) = match x(..) {
+        |_| Some(2) => |_| Some(3),
+        |_| _ => unreachable!(),
+    };
+    assert!(matches!(x(..), |_| Some(4)));
+}
+
 pub fn main() {
     strange();
     funny();
@@ -216,4 +226,5 @@ pub fn main() {
     𝚌𝚘𝚗𝚝𝚒𝚗𝚞𝚎();
     function();
     bathroom_stall();
+    closure_matching();
 }
diff --git a/src/test/ui/wf/issue-103573.rs b/src/test/ui/wf/issue-103573.rs
new file mode 100644
index 000000000000..bcbf4f941ecd
--- /dev/null
+++ b/src/test/ui/wf/issue-103573.rs
@@ -0,0 +1,22 @@
+trait TraitA {
+    type TypeA;
+}
+
+trait TraitD {
+    type TypeD;
+}
+
+pub trait TraitB {
+    type TypeB: TraitD;
+
+    fn f(_: &<Self::TypeB as TraitD>::TypeD);
+}
+
+pub trait TraitC<E> {
+    type TypeC<'a>: TraitB;
+
+    fn g<'a>(_: &<<Self::TypeC<'a> as TraitB>::TypeB as TraitA>::TypeA);
+    //~^ ERROR the trait bound `<<Self as TraitC<E>>::TypeC<'a> as TraitB>::TypeB: TraitA` is not satisfied
+}
+
+fn main() {}
diff --git a/src/test/ui/wf/issue-103573.stderr b/src/test/ui/wf/issue-103573.stderr
new file mode 100644
index 000000000000..fcf3f15e4d3f
--- /dev/null
+++ b/src/test/ui/wf/issue-103573.stderr
@@ -0,0 +1,14 @@
+error[E0277]: the trait bound `<<Self as TraitC<E>>::TypeC<'a> as TraitB>::TypeB: TraitA` is not satisfied
+  --> $DIR/issue-103573.rs:18:5
+   |
+LL |     fn g<'a>(_: &<<Self::TypeC<'a> as TraitB>::TypeB as TraitA>::TypeA);
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `TraitA` is not implemented for `<<Self as TraitC<E>>::TypeC<'a> as TraitB>::TypeB`
+   |
+help: consider further restricting the associated type
+   |
+LL |     fn g<'a>(_: &<<Self::TypeC<'a> as TraitB>::TypeB as TraitA>::TypeA) where <<Self as TraitC<E>>::TypeC<'a> as TraitB>::TypeB: TraitA;
+   |                                                                         +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0277`.
diff --git a/src/test/ui/where-clauses/higher-ranked-fn-type.rs b/src/test/ui/where-clauses/higher-ranked-fn-type.rs
index ab6edde4ee7e..c19e75eb7bfc 100644
--- a/src/test/ui/where-clauses/higher-ranked-fn-type.rs
+++ b/src/test/ui/where-clauses/higher-ranked-fn-type.rs
@@ -19,7 +19,7 @@ where
 {
     called()
     //[quiet]~^ ERROR the trait bound `for<'b> fn(&'b ()): Foo` is not satisfied
-    //[verbose]~^^ ERROR the trait bound `for<'b> fn(&ReLateBound(
+    //[verbose]~^^ ERROR the trait bound `for<Region(
 }
 
 fn main() {}
diff --git a/src/test/ui/where-clauses/higher-ranked-fn-type.verbose.stderr b/src/test/ui/where-clauses/higher-ranked-fn-type.verbose.stderr
index 24660ec3539e..268cef6e2756 100644
--- a/src/test/ui/where-clauses/higher-ranked-fn-type.verbose.stderr
+++ b/src/test/ui/where-clauses/higher-ranked-fn-type.verbose.stderr
@@ -1,8 +1,8 @@
-error[E0277]: the trait bound `for<'b> fn(&ReLateBound(DebruijnIndex(1), BoundRegion { var: 0, kind: BrNamed(DefId(0:6 ~ higher_ranked_fn_type[1209]::called::'b), 'b) }) ()): Foo` is not satisfied
+error[E0277]: the trait bound `for<Region(BrNamed(DefId(0:6 ~ higher_ranked_fn_type[1209]::called::'b), 'b))> fn(&ReLateBound(DebruijnIndex(1), BoundRegion { var: 0, kind: BrNamed(DefId(0:6 ~ higher_ranked_fn_type[1209]::called::'b), 'b) }) ()): Foo` is not satisfied
   --> $DIR/higher-ranked-fn-type.rs:20:5
    |
 LL |     called()
-   |     ^^^^^^ the trait `for<'b> Foo` is not implemented for `fn(&ReLateBound(DebruijnIndex(1), BoundRegion { var: 0, kind: BrNamed(DefId(0:6 ~ higher_ranked_fn_type[1209]::called::'b), 'b) }) ())`
+   |     ^^^^^^ the trait `for<Region(BrNamed(DefId(0:6 ~ higher_ranked_fn_type[1209]::called::'b), 'b))> Foo` is not implemented for `fn(&ReLateBound(DebruijnIndex(1), BoundRegion { var: 0, kind: BrNamed(DefId(0:6 ~ higher_ranked_fn_type[1209]::called::'b), 'b) }) ())`
    |
 note: required by a bound in `called`
   --> $DIR/higher-ranked-fn-type.rs:12:25
diff --git a/src/tools/build-manifest/README.md b/src/tools/build-manifest/README.md
index 44c96f31d0ba..9d30c554186b 100644
--- a/src/tools/build-manifest/README.md
+++ b/src/tools/build-manifest/README.md
@@ -1,7 +1,16 @@
 # build-manifest
 
-This tool generates the manifests uploaded to static.rust-lang.org and used by
-rustup. The tool is invoked by the bootstrap tool.
+This tool generates the manifests uploaded to static.rust-lang.org and used by rustup.
+You can see a full list of all manifests at <https://static.rust-lang.org/manifests.txt>.
+This listing is updated by <https://github.com/rust-lang/generate-manifest-list> every 7 days.
+
+This gets called by `promote-release` <https://github.com/rust-lang/promote-release> via `x.py dist hash-and-sign`.
+
+## Adding a new component
+
+1. Add a new `Step` to `dist.rs`. This should usually be named after the filename of the uploaded tarball. See https://github.com/rust-lang/rust/pull/101799/files#diff-2c56335faa24486df09ba392d8900c57e2fac4633e1f7038469bcf9ed3feb871 for an example.
+    a. If appropriate, call `tarball.is_preview(true)` for the component.
+2. Add a new `PkgType` to build-manifest. Fix all the compile errors as appropriate.
 
 ## Testing changes locally
 
@@ -9,19 +18,16 @@ In order to test the changes locally you need to have a valid dist directory
 available locally. If you don't want to build all the compiler, you can easily
 create one from the nightly artifacts with:
 
-```
-#!/bin/bash
-for cmpn in rust rustc rust-std rust-docs cargo; do
-    wget https://static.rust-lang.org/dist/${cmpn}-nightly-x86_64-unknown-linux-gnu.tar.gz
+```sh
+for component in rust rustc rust-std rust-docs cargo; do
+    wget -P build/dist https://static.rust-lang.org/dist/${component}-nightly-x86_64-unknown-linux-gnu.tar.gz
 done
 ```
 
-Then, you can generate the manifest and all the packages from `path/to/dist` to
-`path/to/output` with:
+Then, you can generate the manifest and all the packages from `build/dist` to
+`build/manifest` with:
 
+```sh
+mkdir -p build/manifest
+cargo +nightly run --release -p build-manifest build/dist build/manifest 1970-01-01 http://example.com nightly
 ```
-$ cargo +nightly run path/to/dist path/to/output 1970-01-01 http://example.com CHANNEL
-```
-
-Remember to replace `CHANNEL` with the channel you produced dist artifacts of
-and `VERSION` with the current Rust version.
diff --git a/src/tools/build-manifest/src/main.rs b/src/tools/build-manifest/src/main.rs
index b0006cb90bdd..0551e835bb0e 100644
--- a/src/tools/build-manifest/src/main.rs
+++ b/src/tools/build-manifest/src/main.rs
@@ -1,8 +1,4 @@
-//! Build a dist manifest, hash and sign everything.
-//! This gets called by `promote-release`
-//! (https://github.com/rust-lang/rust-central-station/tree/master/promote-release)
-//! via `x.py dist hash-and-sign`; the cmdline arguments are set up
-//! by rustbuild (in `src/bootstrap/dist.rs`).
+#![doc = include_str!("../README.md")]
 
 mod checksum;
 mod manifest;
@@ -64,6 +60,7 @@ static TARGETS: &[&str] = &[
     "aarch64-unknown-none",
     "aarch64-unknown-none-softfloat",
     "aarch64-unknown-redox",
+    "aarch64-unknown-uefi",
     "arm-linux-androideabi",
     "arm-unknown-linux-gnueabi",
     "arm-unknown-linux-gnueabihf",
@@ -99,6 +96,7 @@ static TARGETS: &[&str] = &[
     "i686-unknown-freebsd",
     "i686-unknown-linux-gnu",
     "i686-unknown-linux-musl",
+    "i686-unknown-uefi",
     "m68k-unknown-linux-gnu",
     "mips-unknown-linux-gnu",
     "mips-unknown-linux-musl",
@@ -155,6 +153,7 @@ static TARGETS: &[&str] = &[
     "x86_64-unknown-none",
     "x86_64-unknown-redox",
     "x86_64-unknown-hermit",
+    "x86_64-unknown-uefi",
 ];
 
 /// This allows the manifest to contain rust-docs for hosts that don't build
@@ -184,7 +183,7 @@ static PKG_INSTALLERS: &[&str] = &["x86_64-apple-darwin", "aarch64-apple-darwin"
 
 static MINGW: &[&str] = &["i686-pc-windows-gnu", "x86_64-pc-windows-gnu"];
 
-static NIGHTLY_ONLY_COMPONENTS: &[&str] = &["miri-preview", "rust-docs-json-preview"];
+static NIGHTLY_ONLY_COMPONENTS: &[PkgType] = &[PkgType::Miri, PkgType::JsonDocs];
 
 macro_rules! t {
     ($e:expr) => {
@@ -287,28 +286,9 @@ impl Builder {
     }
 
     fn add_packages_to(&mut self, manifest: &mut Manifest) {
-        macro_rules! package {
-            ($name:expr, $targets:expr) => {
-                self.package($name, &mut manifest.pkg, $targets, &[])
-            };
+        for pkg in PkgType::all() {
+            self.package(pkg, &mut manifest.pkg);
         }
-        package!("rustc", HOSTS);
-        package!("rustc-dev", HOSTS);
-        package!("reproducible-artifacts", HOSTS);
-        package!("rustc-docs", HOSTS);
-        package!("cargo", HOSTS);
-        package!("rust-mingw", MINGW);
-        package!("rust-std", TARGETS);
-        self.package("rust-docs", &mut manifest.pkg, HOSTS, DOCS_FALLBACK);
-        self.package("rust-docs-json-preview", &mut manifest.pkg, HOSTS, DOCS_FALLBACK);
-        package!("rust-src", &["*"]);
-        package!("rls-preview", HOSTS);
-        package!("rust-analyzer-preview", HOSTS);
-        package!("clippy-preview", HOSTS);
-        package!("miri-preview", HOSTS);
-        package!("rustfmt-preview", HOSTS);
-        package!("rust-analysis", TARGETS);
-        package!("llvm-tools-preview", TARGETS);
     }
 
     fn add_artifacts_to(&mut self, manifest: &mut Manifest) {
@@ -333,44 +313,28 @@ impl Builder {
     }
 
     fn add_profiles_to(&mut self, manifest: &mut Manifest) {
-        let mut profile = |name, pkgs| self.profile(name, &mut manifest.profiles, pkgs);
-        profile("minimal", &["rustc", "cargo", "rust-std", "rust-mingw"]);
-        profile(
-            "default",
-            &[
-                "rustc",
-                "cargo",
-                "rust-std",
-                "rust-mingw",
-                "rust-docs",
-                "rustfmt-preview",
-                "clippy-preview",
-            ],
-        );
-        profile(
-            "complete",
-            &[
-                "rustc",
-                "cargo",
-                "rust-std",
-                "rust-mingw",
-                "rust-docs",
-                "rustfmt-preview",
-                "clippy-preview",
-                "rls-preview",
-                "rust-analyzer-preview",
-                "rust-src",
-                "llvm-tools-preview",
-                "rust-analysis",
-                "miri-preview",
-            ],
-        );
+        use PkgType::*;
+
+        let mut profile = |name, pkgs: &_| self.profile(name, &mut manifest.profiles, pkgs);
+
+        // Use a Vec here to make sure we don't exclude any components in an earlier profile.
+        let minimal = vec![Rustc, Cargo, RustStd, RustMingw];
+        profile("minimal", &minimal);
+
+        let mut default = minimal;
+        default.extend([HtmlDocs, Rustfmt, Clippy]);
+        profile("default", &default);
+
+        // NOTE: this profile is effectively deprecated; do not add new components to it.
+        let mut complete = default;
+        complete.extend([Rls, RustAnalyzer, RustSrc, LlvmTools, RustAnalysis, Miri]);
+        profile("complete", &complete);
 
         // The compiler libraries are not stable for end users, and they're also huge, so we only
         // `rustc-dev` for nightly users, and only in the "complete" profile. It's still possible
         // for users to install the additional component manually, if needed.
         if self.versions.channel() == "nightly" {
-            self.extend_profile("complete", &mut manifest.profiles, &["rustc-dev"]);
+            self.extend_profile("complete", &mut manifest.profiles, &[RustcDev]);
             // Do not include the rustc-docs component for now, as it causes
             // conflicts with the rust-docs component when installed. See
             // #75833.
@@ -382,12 +346,11 @@ impl Builder {
         let mut rename = |from: &str, to: &str| {
             manifest.renames.insert(from.to_owned(), Rename { to: to.to_owned() })
         };
-        rename("rls", "rls-preview");
-        rename("rustfmt", "rustfmt-preview");
-        rename("clippy", "clippy-preview");
-        rename("miri", "miri-preview");
-        rename("rust-docs-json", "rust-docs-json-preview");
-        rename("rust-analyzer", "rust-analyzer-preview");
+        for pkg in PkgType::all() {
+            if pkg.is_preview() {
+                rename(pkg.tarball_component_name(), &pkg.manifest_component_name());
+            }
+        }
     }
 
     fn rust_package(&mut self, manifest: &Manifest) -> Package {
@@ -419,43 +382,53 @@ impl Builder {
         let mut components = Vec::new();
         let mut extensions = Vec::new();
 
-        let host_component = |pkg| Component::from_str(pkg, host);
+        let host_component = |pkg: &_| Component::from_pkg(pkg, host);
 
-        // rustc/rust-std/cargo/docs are all required,
-        // and so is rust-mingw if it's available for the target.
-        components.extend(vec![
-            host_component("rustc"),
-            host_component("rust-std"),
-            host_component("cargo"),
-            host_component("rust-docs"),
-        ]);
-        if host.contains("pc-windows-gnu") {
-            components.push(host_component("rust-mingw"));
+        for pkg in PkgType::all() {
+            match pkg {
+                // rustc/rust-std/cargo/docs are all required
+                PkgType::Rustc | PkgType::Cargo | PkgType::HtmlDocs => {
+                    components.push(host_component(pkg));
+                }
+                PkgType::RustStd => {
+                    components.push(host_component(pkg));
+                    extensions.extend(
+                        TARGETS
+                            .iter()
+                            .filter(|&&target| target != host)
+                            .map(|target| Component::from_pkg(pkg, target)),
+                    );
+                }
+                // so is rust-mingw if it's available for the target
+                PkgType::RustMingw => {
+                    if host.contains("pc-windows-gnu") {
+                        components.push(host_component(pkg));
+                    }
+                }
+                // Tools are always present in the manifest,
+                // but might be marked as unavailable if they weren't built.
+                PkgType::Clippy
+                | PkgType::Miri
+                | PkgType::Rls
+                | PkgType::RustAnalyzer
+                | PkgType::Rustfmt
+                | PkgType::LlvmTools
+                | PkgType::RustAnalysis
+                | PkgType::JsonDocs => {
+                    extensions.push(host_component(pkg));
+                }
+                PkgType::RustcDev | PkgType::RustcDocs => {
+                    extensions.extend(HOSTS.iter().map(|target| Component::from_pkg(pkg, target)));
+                }
+                PkgType::RustSrc => {
+                    extensions.push(Component::from_pkg(pkg, "*"));
+                }
+                PkgType::Rust => {}
+                // NOTE: this is intentional, these artifacts aren't intended to be used with rustup
+                PkgType::ReproducibleArtifacts => {}
+            }
         }
 
-        // Tools are always present in the manifest,
-        // but might be marked as unavailable if they weren't built.
-        extensions.extend(vec![
-            host_component("clippy-preview"),
-            host_component("miri-preview"),
-            host_component("rls-preview"),
-            host_component("rust-analyzer-preview"),
-            host_component("rustfmt-preview"),
-            host_component("llvm-tools-preview"),
-            host_component("rust-analysis"),
-            host_component("rust-docs-json-preview"),
-        ]);
-
-        extensions.extend(
-            TARGETS
-                .iter()
-                .filter(|&&target| target != host)
-                .map(|target| Component::from_str("rust-std", target)),
-        );
-        extensions.extend(HOSTS.iter().map(|target| Component::from_str("rustc-dev", target)));
-        extensions.extend(HOSTS.iter().map(|target| Component::from_str("rustc-docs", target)));
-        extensions.push(Component::from_str("rust-src", "*"));
-
         // If the components/extensions don't actually exist for this
         // particular host/target combination then nix it entirely from our
         // lists.
@@ -481,43 +454,44 @@ impl Builder {
         &mut self,
         profile_name: &str,
         dst: &mut BTreeMap<String, Vec<String>>,
-        pkgs: &[&str],
+        pkgs: &[PkgType],
     ) {
-        dst.insert(profile_name.to_owned(), pkgs.iter().map(|s| (*s).to_owned()).collect());
+        dst.insert(
+            profile_name.to_owned(),
+            pkgs.iter().map(|s| s.manifest_component_name()).collect(),
+        );
     }
 
     fn extend_profile(
         &mut self,
         profile_name: &str,
         dst: &mut BTreeMap<String, Vec<String>>,
-        pkgs: &[&str],
+        pkgs: &[PkgType],
     ) {
         dst.get_mut(profile_name)
             .expect("existing profile")
-            .extend(pkgs.iter().map(|s| (*s).to_owned()));
+            .extend(pkgs.iter().map(|s| s.manifest_component_name()));
     }
 
-    fn package(
-        &mut self,
-        pkgname: &str,
-        dst: &mut BTreeMap<String, Package>,
-        targets: &[&str],
-        fallback: &[(&str, &str)],
-    ) {
-        let version_info = self
-            .versions
-            .version(&PkgType::from_component(pkgname))
-            .expect("failed to load package version");
+    fn package(&mut self, pkg: &PkgType, dst: &mut BTreeMap<String, Package>) {
+        if *pkg == PkgType::Rust {
+            // This is handled specially by `rust_package` later.
+            // Order is important, so don't call `rust_package` here.
+            return;
+        }
+
+        let fallback = if pkg.use_docs_fallback() { DOCS_FALLBACK } else { &[] };
+        let version_info = self.versions.version(&pkg).expect("failed to load package version");
         let mut is_present = version_info.present;
 
         // Never ship nightly-only components for other trains.
-        if self.versions.channel() != "nightly" && NIGHTLY_ONLY_COMPONENTS.contains(&pkgname) {
+        if self.versions.channel() != "nightly" && NIGHTLY_ONLY_COMPONENTS.contains(&pkg) {
             is_present = false; // Pretend the component is entirely missing.
         }
 
         macro_rules! tarball_name {
             ($target_name:expr) => {
-                self.versions.tarball_name(&PkgType::from_component(pkgname), $target_name).unwrap()
+                self.versions.tarball_name(pkg, $target_name).unwrap()
             };
         }
         let mut target_from_compressed_tar = |target_name| {
@@ -546,7 +520,8 @@ impl Builder {
             Target::unavailable()
         };
 
-        let targets = targets
+        let targets = pkg
+            .targets()
             .iter()
             .map(|name| {
                 let target = if is_present {
@@ -561,7 +536,7 @@ impl Builder {
             .collect();
 
         dst.insert(
-            pkgname.to_string(),
+            pkg.manifest_component_name(),
             Package {
                 version: version_info.version.unwrap_or_default(),
                 git_commit_hash: version_info.git_commit,
diff --git a/src/tools/build-manifest/src/manifest.rs b/src/tools/build-manifest/src/manifest.rs
index 547c270d89ab..a9f19d8e5653 100644
--- a/src/tools/build-manifest/src/manifest.rs
+++ b/src/tools/build-manifest/src/manifest.rs
@@ -1,3 +1,4 @@
+use crate::versions::PkgType;
 use crate::Builder;
 use serde::{Serialize, Serializer};
 use std::collections::BTreeMap;
@@ -116,8 +117,8 @@ pub(crate) struct Component {
 }
 
 impl Component {
-    pub(crate) fn from_str(pkg: &str, target: &str) -> Self {
-        Self { pkg: pkg.to_string(), target: target.to_string() }
+    pub(crate) fn from_pkg(pkg: &PkgType, target: &str) -> Self {
+        Self { pkg: pkg.manifest_component_name(), target: target.to_string() }
     }
 }
 
diff --git a/src/tools/build-manifest/src/versions.rs b/src/tools/build-manifest/src/versions.rs
index 0186194a41f5..dde9745afb78 100644
--- a/src/tools/build-manifest/src/versions.rs
+++ b/src/tools/build-manifest/src/versions.rs
@@ -8,55 +8,63 @@ use tar::Archive;
 
 const DEFAULT_TARGET: &str = "x86_64-unknown-linux-gnu";
 
-#[derive(Debug, Hash, Eq, PartialEq, Clone)]
-pub(crate) enum PkgType {
-    Rust,
-    RustSrc,
-    Rustc,
-    Cargo,
-    Rls,
-    RustAnalyzer,
-    Clippy,
-    Rustfmt,
-    LlvmTools,
-    Miri,
-    JsonDocs,
-    Other(String),
+macro_rules! pkg_type {
+    ( $($variant:ident = $component:literal $(; preview = true $(@$is_preview:tt)? )? ),+ $(,)? ) => {
+        #[derive(Debug, Hash, Eq, PartialEq, Clone)]
+        pub(crate) enum PkgType {
+            $($variant,)+
+        }
+
+        impl PkgType {
+            pub(crate) fn is_preview(&self) -> bool {
+                match self {
+                    $( $( $($is_preview)? PkgType::$variant => true, )? )+
+                    _ => false,
+                }
+            }
+
+            /// First part of the tarball name.
+            pub(crate) fn tarball_component_name(&self) -> &str {
+                match self {
+                    $( PkgType::$variant => $component,)+
+                }
+            }
+
+            pub(crate) fn all() -> &'static [PkgType] {
+                &[ $(PkgType::$variant),+ ]
+            }
+        }
+    }
+}
+
+pkg_type! {
+    Rust = "rust",
+    RustSrc = "rust-src",
+    Rustc = "rustc",
+    RustcDev = "rustc-dev",
+    RustcDocs = "rustc-docs",
+    ReproducibleArtifacts = "reproducible-artifacts",
+    RustMingw = "rust-mingw",
+    RustStd = "rust-std",
+    Cargo = "cargo",
+    HtmlDocs = "rust-docs",
+    RustAnalysis = "rust-analysis",
+    Rls = "rls"; preview = true,
+    RustAnalyzer = "rust-analyzer"; preview = true,
+    Clippy = "clippy"; preview = true,
+    Rustfmt = "rustfmt"; preview = true,
+    LlvmTools = "llvm-tools"; preview = true,
+    Miri = "miri"; preview = true,
+    JsonDocs = "rust-docs-json"; preview = true,
 }
 
 impl PkgType {
-    pub(crate) fn from_component(component: &str) -> Self {
-        match component {
-            "rust" => PkgType::Rust,
-            "rust-src" => PkgType::RustSrc,
-            "rustc" => PkgType::Rustc,
-            "cargo" => PkgType::Cargo,
-            "rls" | "rls-preview" => PkgType::Rls,
-            "rust-analyzer" | "rust-analyzer-preview" => PkgType::RustAnalyzer,
-            "clippy" | "clippy-preview" => PkgType::Clippy,
-            "rustfmt" | "rustfmt-preview" => PkgType::Rustfmt,
-            "llvm-tools" | "llvm-tools-preview" => PkgType::LlvmTools,
-            "miri" | "miri-preview" => PkgType::Miri,
-            "rust-docs-json" | "rust-docs-json-preview" => PkgType::JsonDocs,
-            other => PkgType::Other(other.into()),
-        }
-    }
-
-    /// First part of the tarball name.
-    fn tarball_component_name(&self) -> &str {
-        match self {
-            PkgType::Rust => "rust",
-            PkgType::RustSrc => "rust-src",
-            PkgType::Rustc => "rustc",
-            PkgType::Cargo => "cargo",
-            PkgType::Rls => "rls",
-            PkgType::RustAnalyzer => "rust-analyzer",
-            PkgType::Clippy => "clippy",
-            PkgType::Rustfmt => "rustfmt",
-            PkgType::LlvmTools => "llvm-tools",
-            PkgType::Miri => "miri",
-            PkgType::JsonDocs => "rust-docs-json",
-            PkgType::Other(component) => component,
+    /// Component name in the manifest. In particular, this includes the `-preview` suffix where appropriate.
+    pub(crate) fn manifest_component_name(&self) -> String {
+        if self.is_preview() {
+            format!("{}-preview", self.tarball_component_name())
+        } else {
+            self.tarball_component_name().to_string()
         }
     }
 
@@ -73,10 +81,42 @@ impl PkgType {
             PkgType::Miri => false,
 
             PkgType::Rust => true,
+            PkgType::RustStd => true,
             PkgType::RustSrc => true,
             PkgType::Rustc => true,
             PkgType::JsonDocs => true,
-            PkgType::Other(_) => true,
+            PkgType::HtmlDocs => true,
+            PkgType::RustcDev => true,
+            PkgType::RustcDocs => true,
+            PkgType::ReproducibleArtifacts => true,
+            PkgType::RustMingw => true,
+            PkgType::RustAnalysis => true,
+        }
+    }
+
+    pub(crate) fn targets(&self) -> &[&str] {
+        use crate::{HOSTS, MINGW, TARGETS};
+        use PkgType::*;
+
+        match self {
+            Rust => HOSTS, // doesn't matter in practice, but return something to avoid panicking
+            Rustc => HOSTS,
+            RustcDev => HOSTS,
+            ReproducibleArtifacts => HOSTS,
+            RustcDocs => HOSTS,
+            Cargo => HOSTS,
+            RustMingw => MINGW,
+            RustStd => TARGETS,
+            HtmlDocs => HOSTS,
+            JsonDocs => HOSTS,
+            RustSrc => &["*"],
+            Rls => HOSTS,
+            RustAnalyzer => HOSTS,
+            Clippy => HOSTS,
+            Miri => HOSTS,
+            Rustfmt => HOSTS,
+            RustAnalysis => TARGETS,
+            LlvmTools => TARGETS,
         }
     }
 
@@ -84,6 +124,14 @@ impl PkgType {
     fn target_independent(&self) -> bool {
         *self == PkgType::RustSrc
     }
+
+    /// Whether to package these target-specific docs for another similar target.
+    pub(crate) fn use_docs_fallback(&self) -> bool {
+        match self {
+            PkgType::JsonDocs | PkgType::HtmlDocs => true,
+            _ => false,
+        }
+    }
 }
 
 #[derive(Debug, Default, Clone)]
diff --git a/src/tools/cargo b/src/tools/cargo
index 071eeaf21070..a3dfea71ca0c 160000
--- a/src/tools/cargo
+++ b/src/tools/cargo
@@ -1 +1 @@
-Subproject commit 071eeaf210708219a5a1b2c4728ca2f97df7f2ae
+Subproject commit a3dfea71ca0c888a88111086898aa833c291d497
diff --git a/src/tools/cargotest/main.rs b/src/tools/cargotest/main.rs
index 95fe98a683ff..7044cb892869 100644
--- a/src/tools/cargotest/main.rs
+++ b/src/tools/cargotest/main.rs
@@ -73,7 +73,7 @@ const TEST_REPOS: &[Test] = &[
     Test {
         name: "servo",
         repo: "https://github.com/servo/servo",
-        sha: "caac107ae8145ef2fd20365e2b8fadaf09c2eb3b",
+        sha: "785a344e32db58d4e631fd3cae17fd1f29a721ab",
         lock: None,
         // Only test Stylo a.k.a. Quantum CSS, the parts of Servo going into Firefox.
         // This takes much less time to build than all of Servo and supports stable Rust.
@@ -206,6 +206,10 @@ fn run_cargo_test(
         .env("CFG_DISABLE_CROSS_TESTS", "1")
         // Relax #![deny(warnings)] in some crates
         .env("RUSTFLAGS", "--cap-lints warn")
+        // servo tries to use 'lld-link.exe' on windows, but we don't
+        // have lld on our PATH in CI. Override it to use 'link.exe'
+        .env("CARGO_TARGET_X86_64_PC_WINDOWS_MSVC_LINKER", "link.exe")
+        .env("CARGO_TARGET_I686_PC_WINDOWS_MSVC_LINKER", "link.exe")
         .current_dir(crate_path)
         .status()
         .unwrap();
diff --git a/src/tools/clippy/.github/workflows/clippy.yml b/src/tools/clippy/.github/workflows/clippy.yml
index fac2c99714d9..b99213011971 100644
--- a/src/tools/clippy/.github/workflows/clippy.yml
+++ b/src/tools/clippy/.github/workflows/clippy.yml
@@ -25,6 +25,7 @@ env:
   CARGO_TARGET_DIR: '${{ github.workspace }}/target'
   NO_FMT_TEST: 1
   CARGO_INCREMENTAL: 0
+  CARGO_UNSTABLE_SPARSE_REGISTRY: true
 
 jobs:
   base:
diff --git a/src/tools/clippy/.github/workflows/clippy_bors.yml b/src/tools/clippy/.github/workflows/clippy_bors.yml
index 30607af49012..6448b2d4068d 100644
--- a/src/tools/clippy/.github/workflows/clippy_bors.yml
+++ b/src/tools/clippy/.github/workflows/clippy_bors.yml
@@ -11,6 +11,7 @@ env:
   CARGO_TARGET_DIR: '${{ github.workspace }}/target'
   NO_FMT_TEST: 1
   CARGO_INCREMENTAL: 0
+  CARGO_UNSTABLE_SPARSE_REGISTRY: true
 
 defaults:
   run:
diff --git a/src/tools/clippy/.github/workflows/clippy_dev.yml b/src/tools/clippy/.github/workflows/clippy_dev.yml
index 22051093c9cf..14f20212adda 100644
--- a/src/tools/clippy/.github/workflows/clippy_dev.yml
+++ b/src/tools/clippy/.github/workflows/clippy_dev.yml
@@ -15,6 +15,8 @@ on:
 
 env:
   RUST_BACKTRACE: 1
+  CARGO_INCREMENTAL: 0
+  CARGO_UNSTABLE_SPARSE_REGISTRY: true
 
 jobs:
   clippy_dev:
diff --git a/src/tools/clippy/CHANGELOG.md b/src/tools/clippy/CHANGELOG.md
index 42615179f705..2d7bda27e4fc 100644
--- a/src/tools/clippy/CHANGELOG.md
+++ b/src/tools/clippy/CHANGELOG.md
@@ -3735,6 +3735,7 @@ Released 2018-09-13
 [`approx_constant`]: https://rust-lang.github.io/rust-clippy/master/index.html#approx_constant
 [`arithmetic_side_effects`]: https://rust-lang.github.io/rust-clippy/master/index.html#arithmetic_side_effects
 [`as_conversions`]: https://rust-lang.github.io/rust-clippy/master/index.html#as_conversions
+[`as_ptr_cast_mut`]: https://rust-lang.github.io/rust-clippy/master/index.html#as_ptr_cast_mut
 [`as_underscore`]: https://rust-lang.github.io/rust-clippy/master/index.html#as_underscore
 [`assertions_on_constants`]: https://rust-lang.github.io/rust-clippy/master/index.html#assertions_on_constants
 [`assertions_on_result_states`]: https://rust-lang.github.io/rust-clippy/master/index.html#assertions_on_result_states
@@ -3772,6 +3773,7 @@ Released 2018-09-13
 [`cast_enum_constructor`]: https://rust-lang.github.io/rust-clippy/master/index.html#cast_enum_constructor
 [`cast_enum_truncation`]: https://rust-lang.github.io/rust-clippy/master/index.html#cast_enum_truncation
 [`cast_lossless`]: https://rust-lang.github.io/rust-clippy/master/index.html#cast_lossless
+[`cast_nan_to_int`]: https://rust-lang.github.io/rust-clippy/master/index.html#cast_nan_to_int
 [`cast_possible_truncation`]: https://rust-lang.github.io/rust-clippy/master/index.html#cast_possible_truncation
 [`cast_possible_wrap`]: https://rust-lang.github.io/rust-clippy/master/index.html#cast_possible_wrap
 [`cast_precision_loss`]: https://rust-lang.github.io/rust-clippy/master/index.html#cast_precision_loss
@@ -3988,6 +3990,7 @@ Released 2018-09-13
 [`manual_async_fn`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_async_fn
 [`manual_bits`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_bits
 [`manual_clamp`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_clamp
+[`manual_filter`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_filter
 [`manual_filter_map`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_filter_map
 [`manual_find`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_find
 [`manual_find_map`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_find_map
@@ -4046,6 +4049,7 @@ Released 2018-09-13
 [`missing_panics_doc`]: https://rust-lang.github.io/rust-clippy/master/index.html#missing_panics_doc
 [`missing_safety_doc`]: https://rust-lang.github.io/rust-clippy/master/index.html#missing_safety_doc
 [`missing_spin_loop`]: https://rust-lang.github.io/rust-clippy/master/index.html#missing_spin_loop
+[`missing_trait_methods`]: https://rust-lang.github.io/rust-clippy/master/index.html#missing_trait_methods
 [`mistyped_literal_suffixes`]: https://rust-lang.github.io/rust-clippy/master/index.html#mistyped_literal_suffixes
 [`mixed_case_hex_literals`]: https://rust-lang.github.io/rust-clippy/master/index.html#mixed_case_hex_literals
 [`mixed_read_write_in_expression`]: https://rust-lang.github.io/rust-clippy/master/index.html#mixed_read_write_in_expression
@@ -4131,6 +4135,7 @@ Released 2018-09-13
 [`panic_in_result_fn`]: https://rust-lang.github.io/rust-clippy/master/index.html#panic_in_result_fn
 [`panic_params`]: https://rust-lang.github.io/rust-clippy/master/index.html#panic_params
 [`panicking_unwrap`]: https://rust-lang.github.io/rust-clippy/master/index.html#panicking_unwrap
+[`partial_pub_fields`]: https://rust-lang.github.io/rust-clippy/master/index.html#partial_pub_fields
 [`partialeq_ne_impl`]: https://rust-lang.github.io/rust-clippy/master/index.html#partialeq_ne_impl
 [`partialeq_to_none`]: https://rust-lang.github.io/rust-clippy/master/index.html#partialeq_to_none
 [`path_buf_push_overwrite`]: https://rust-lang.github.io/rust-clippy/master/index.html#path_buf_push_overwrite
@@ -4312,6 +4317,7 @@ Released 2018-09-13
 [`unstable_as_slice`]: https://rust-lang.github.io/rust-clippy/master/index.html#unstable_as_slice
 [`unused_async`]: https://rust-lang.github.io/rust-clippy/master/index.html#unused_async
 [`unused_collect`]: https://rust-lang.github.io/rust-clippy/master/index.html#unused_collect
+[`unused_format_specs`]: https://rust-lang.github.io/rust-clippy/master/index.html#unused_format_specs
 [`unused_io_amount`]: https://rust-lang.github.io/rust-clippy/master/index.html#unused_io_amount
 [`unused_label`]: https://rust-lang.github.io/rust-clippy/master/index.html#unused_label
 [`unused_peekable`]: https://rust-lang.github.io/rust-clippy/master/index.html#unused_peekable
diff --git a/src/tools/clippy/CONTRIBUTING.md b/src/tools/clippy/CONTRIBUTING.md
index 6c977b2cacab..85f94a74ad91 100644
--- a/src/tools/clippy/CONTRIBUTING.md
+++ b/src/tools/clippy/CONTRIBUTING.md
@@ -29,7 +29,7 @@ All contributors are expected to follow the [Rust Code of Conduct].
 
 ## The Clippy book
 
-If you're new to Clippy and don't know where to start the [Clippy book] includes
+If you're new to Clippy and don't know where to start, the [Clippy book] includes
 a [developer guide] and is a good place to start your journey.
 
 [Clippy book]: https://doc.rust-lang.org/nightly/clippy/index.html
diff --git a/src/tools/clippy/book/src/development/adding_lints.md b/src/tools/clippy/book/src/development/adding_lints.md
index b1e843bc7f4c..3c3f368a529b 100644
--- a/src/tools/clippy/book/src/development/adding_lints.md
+++ b/src/tools/clippy/book/src/development/adding_lints.md
@@ -478,8 +478,27 @@ impl<'tcx> LateLintPass<'tcx> for ManualStrip {
 ```
 
 Once the `msrv` is added to the lint, a relevant test case should be added to
-`tests/ui/min_rust_version_attr.rs` which verifies that the lint isn't emitted
-if the project's MSRV is lower.
+the lint's test file, `tests/ui/manual_strip.rs` in this example. It should
+have a case for the version below the MSRV and one with the same contents but
+for the MSRV version itself.
+
+```rust
+#![feature(custom_inner_attributes)]
+
+...
+
+fn msrv_1_44() {
+    #![clippy::msrv = "1.44"]
+
+    /* something that would trigger the lint */
+}
+
+fn msrv_1_45() {
+    #![clippy::msrv = "1.45"]
+
+    /* something that would trigger the lint */
+}
+```
 
 As a last step, the lint should be added to the lint documentation. This is done
 in `clippy_lints/src/utils/conf.rs`:
diff --git a/src/tools/clippy/book/src/development/basics.md b/src/tools/clippy/book/src/development/basics.md
index 44ba6e32755e..6fb53236e6f1 100644
--- a/src/tools/clippy/book/src/development/basics.md
+++ b/src/tools/clippy/book/src/development/basics.md
@@ -69,7 +69,7 @@ the reference file with:
 cargo dev bless
 ```
 
-For example, this is necessary, if you fix a typo in an error message of a lint
+For example, this is necessary if you fix a typo in an error message of a lint,
 or if you modify a test file to add a test case.
 
 > _Note:_ This command may update more files than you intended. In that case
@@ -101,8 +101,9 @@ cargo dev setup intellij
 cargo dev dogfood
 ```
 
-More about intellij command usage and reasons
-[here](https://github.com/rust-lang/rust-clippy/blob/master/CONTRIBUTING.md#intellij-rust)
+More about [intellij] command usage and reasons.
+
+[intellij]: https://github.com/rust-lang/rust-clippy/blob/master/CONTRIBUTING.md#intellij-rust
 
 ## lintcheck
 
diff --git a/src/tools/clippy/clippy_dev/src/serve.rs b/src/tools/clippy/clippy_dev/src/serve.rs
index 2e0794f12fa1..535c25e69f1b 100644
--- a/src/tools/clippy/clippy_dev/src/serve.rs
+++ b/src/tools/clippy/clippy_dev/src/serve.rs
@@ -49,7 +49,7 @@ fn mtime(path: impl AsRef<Path>) -> SystemTime {
             .into_iter()
             .flatten()
             .flatten()
-            .map(|entry| mtime(&entry.path()))
+            .map(|entry| mtime(entry.path()))
             .max()
             .unwrap_or(SystemTime::UNIX_EPOCH)
     } else {
diff --git a/src/tools/clippy/clippy_dev/src/setup/intellij.rs b/src/tools/clippy/clippy_dev/src/setup/intellij.rs
index b64e79733eb2..efdb158c21e9 100644
--- a/src/tools/clippy/clippy_dev/src/setup/intellij.rs
+++ b/src/tools/clippy/clippy_dev/src/setup/intellij.rs
@@ -36,9 +36,8 @@ impl ClippyProjectInfo {
 }
 
 pub fn setup_rustc_src(rustc_path: &str) {
-    let rustc_source_dir = match check_and_get_rustc_dir(rustc_path) {
-        Ok(path) => path,
-        Err(_) => return,
+    let Ok(rustc_source_dir) = check_and_get_rustc_dir(rustc_path) else {
+        return
     };
 
     for project in CLIPPY_PROJECTS {
@@ -172,14 +171,10 @@ pub fn remove_rustc_src() {
 }
 
 fn remove_rustc_src_from_project(project: &ClippyProjectInfo) -> bool {
-    let mut cargo_content = if let Ok(content) = read_project_file(project.cargo_file) {
-        content
-    } else {
+    let Ok(mut cargo_content) = read_project_file(project.cargo_file) else {
         return false;
     };
-    let section_start = if let Some(section_start) = cargo_content.find(RUSTC_PATH_SECTION) {
-        section_start
-    } else {
+    let Some(section_start) = cargo_content.find(RUSTC_PATH_SECTION) else {
         println!(
             "info: dependencies could not be found in `{}` for {}, skipping file",
             project.cargo_file, project.name
@@ -187,9 +182,7 @@ fn remove_rustc_src_from_project(project: &ClippyProjectInfo) -> bool {
         return true;
     };
 
-    let end_point = if let Some(end_point) = cargo_content.find(DEPENDENCIES_SECTION) {
-        end_point
-    } else {
+    let Some(end_point) = cargo_content.find(DEPENDENCIES_SECTION) else {
         eprintln!(
             "error: the end of the rustc dependencies section could not be found in `{}`",
             project.cargo_file
diff --git a/src/tools/clippy/clippy_dev/src/update_lints.rs b/src/tools/clippy/clippy_dev/src/update_lints.rs
index 0eb443167ecf..e690bc369cd4 100644
--- a/src/tools/clippy/clippy_dev/src/update_lints.rs
+++ b/src/tools/clippy/clippy_dev/src/update_lints.rs
@@ -128,7 +128,7 @@ fn generate_lint_files(
     for (lint_group, lints) in Lint::by_lint_group(usable_lints.into_iter().chain(internal_lints)) {
         let content = gen_lint_group_list(&lint_group, lints.iter());
         process_file(
-            &format!("clippy_lints/src/lib.register_{lint_group}.rs"),
+            format!("clippy_lints/src/lib.register_{lint_group}.rs"),
             update_mode,
             &content,
         );
@@ -869,13 +869,11 @@ fn clippy_lints_src_files() -> impl Iterator<Item = (PathBuf, DirEntry)> {
 macro_rules! match_tokens {
     ($iter:ident, $($token:ident $({$($fields:tt)*})? $(($capture:ident))?)*) => {
          {
-            $($(let $capture =)? if let Some(LintDeclSearchResult {
+            $(#[allow(clippy::redundant_pattern)] let Some(LintDeclSearchResult {
                     token_kind: TokenKind::$token $({$($fields)*})?,
-                    content: _x,
+                    content: $($capture @)? _,
                     ..
-            }) = $iter.next() {
-                _x
-            } else {
+            }) = $iter.next() else {
                 continue;
             };)*
             #[allow(clippy::unused_unit)]
diff --git a/src/tools/clippy/clippy_lints/src/booleans.rs b/src/tools/clippy/clippy_lints/src/booleans.rs
index 2a15cbc7a3c3..08164c0b654e 100644
--- a/src/tools/clippy/clippy_lints/src/booleans.rs
+++ b/src/tools/clippy/clippy_lints/src/booleans.rs
@@ -1,7 +1,7 @@
 use clippy_utils::diagnostics::{span_lint_and_sugg, span_lint_hir_and_then};
+use clippy_utils::eq_expr_value;
 use clippy_utils::source::snippet_opt;
 use clippy_utils::ty::{implements_trait, is_type_diagnostic_item};
-use clippy_utils::{eq_expr_value, get_trait_def_id, paths};
 use if_chain::if_chain;
 use rustc_ast::ast::LitKind;
 use rustc_errors::Applicability;
@@ -483,7 +483,9 @@ impl<'a, 'tcx> Visitor<'tcx> for NonminimalBoolVisitor<'a, 'tcx> {
 
 fn implements_ord<'tcx>(cx: &LateContext<'tcx>, expr: &Expr<'_>) -> bool {
     let ty = cx.typeck_results().expr_ty(expr);
-    get_trait_def_id(cx, &paths::ORD).map_or(false, |id| implements_trait(cx, ty, id, &[]))
+    cx.tcx
+        .get_diagnostic_item(sym::Ord)
+        .map_or(false, |id| implements_trait(cx, ty, id, &[]))
 }
 
 struct NotSimplificationVisitor<'a, 'tcx> {
diff --git a/src/tools/clippy/clippy_lints/src/box_default.rs b/src/tools/clippy/clippy_lints/src/box_default.rs
index 792183ac4081..36daceabe0be 100644
--- a/src/tools/clippy/clippy_lints/src/box_default.rs
+++ b/src/tools/clippy/clippy_lints/src/box_default.rs
@@ -1,5 +1,12 @@
-use clippy_utils::{diagnostics::span_lint_and_help, is_default_equivalent, path_def_id};
-use rustc_hir::{Expr, ExprKind, QPath};
+use clippy_utils::{
+    diagnostics::span_lint_and_sugg, get_parent_node, is_default_equivalent, macros::macro_backtrace, match_path,
+    path_def_id, paths, ty::expr_sig,
+};
+use rustc_errors::Applicability;
+use rustc_hir::{
+    intravisit::{walk_ty, Visitor},
+    Block, Expr, ExprKind, Local, Node, QPath, TyKind,
+};
 use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_middle::lint::in_external_macro;
 use rustc_session::{declare_lint_pass, declare_tool_lint};
@@ -15,12 +22,6 @@ declare_clippy_lint! {
     /// Second, `Box::default()` can be faster
     /// [in certain cases](https://nnethercote.github.io/perf-book/standard-library-types.html#box).
     ///
-    /// ### Known problems
-    /// The lint may miss some cases (e.g. Box::new(String::from(""))).
-    /// On the other hand, it will trigger on cases where the `default`
-    /// code comes from a macro that does something different based on
-    /// e.g. target operating system.
-    ///
     /// ### Example
     /// ```rust
     /// let x: Box<String> = Box::new(Default::default());
@@ -41,21 +42,88 @@ impl LateLintPass<'_> for BoxDefault {
     fn check_expr(&mut self, cx: &LateContext<'_>, expr: &Expr<'_>) {
         if let ExprKind::Call(box_new, [arg]) = expr.kind
             && let ExprKind::Path(QPath::TypeRelative(ty, seg)) = box_new.kind
-            && let ExprKind::Call(..) = arg.kind
+            && let ExprKind::Call(arg_path, ..) = arg.kind
             && !in_external_macro(cx.sess(), expr.span)
-            && expr.span.eq_ctxt(arg.span)
+            && (expr.span.eq_ctxt(arg.span) || is_vec_expn(cx, arg))
             && seg.ident.name == sym::new
-            && path_def_id(cx, ty) == cx.tcx.lang_items().owned_box()
+            && path_def_id(cx, ty).map_or(false, |id| Some(id) == cx.tcx.lang_items().owned_box())
             && is_default_equivalent(cx, arg)
         {
-            span_lint_and_help(
+            let arg_ty = cx.typeck_results().expr_ty(arg);
+            span_lint_and_sugg(
                 cx,
                 BOX_DEFAULT,
                 expr.span,
                 "`Box::new(_)` of default value",
-                None,
-                "use `Box::default()` instead",
+                "try",
+                if is_plain_default(arg_path) || given_type(cx, expr) {
+                    "Box::default()".into()
+                } else {
+                    format!("Box::<{arg_ty}>::default()")
+                },
+                Applicability::MachineApplicable
             );
         }
     }
 }
+
+fn is_plain_default(arg_path: &Expr<'_>) -> bool {
+    // we need to match the actual path so we don't match e.g. "u8::default"
+    if let ExprKind::Path(QPath::Resolved(None, path)) = &arg_path.kind {
+        // avoid generic parameters
+        match_path(path, &paths::DEFAULT_TRAIT_METHOD) && path.segments.iter().all(|seg| seg.args.is_none())
+    } else {
+        false
+    }
+}
+
+fn is_vec_expn(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
+    macro_backtrace(expr.span)
+        .next()
+        .map_or(false, |call| cx.tcx.is_diagnostic_item(sym::vec_macro, call.def_id))
+}
+
+#[derive(Default)]
+struct InferVisitor(bool);
+
+impl<'tcx> Visitor<'tcx> for InferVisitor {
+    fn visit_ty(&mut self, t: &rustc_hir::Ty<'_>) {
+        self.0 |= matches!(t.kind, TyKind::Infer | TyKind::OpaqueDef(..) | TyKind::TraitObject(..));
+        if !self.0 {
+            walk_ty(self, t);
+        }
+    }
+}
+
+fn given_type(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
+    match get_parent_node(cx.tcx, expr.hir_id) {
+        Some(Node::Local(Local { ty: Some(ty), .. })) => {
+            let mut v = InferVisitor::default();
+            v.visit_ty(ty);
+            !v.0
+        },
+        Some(
+            Node::Expr(Expr {
+                kind: ExprKind::Call(path, args),
+                ..
+            }) | Node::Block(Block {
+                expr:
+                    Some(Expr {
+                        kind: ExprKind::Call(path, args),
+                        ..
+                    }),
+                ..
+            }),
+        ) => {
+            if let Some(index) = args.iter().position(|arg| arg.hir_id == expr.hir_id) &&
+                let Some(sig) = expr_sig(cx, path) &&
+                let Some(input) = sig.input(index)
+            {
+                input.no_bound_vars().is_some()
+            } else {
+                false
+            }
+        },
+        _ => false,
+    }
+}
diff --git a/src/tools/clippy/clippy_lints/src/casts/as_ptr_cast_mut.rs b/src/tools/clippy/clippy_lints/src/casts/as_ptr_cast_mut.rs
new file mode 100644
index 000000000000..9409f4844f54
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/casts/as_ptr_cast_mut.rs
@@ -0,0 +1,38 @@
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::source::snippet_opt;
+use rustc_errors::Applicability;
+use rustc_hir::{Expr, ExprKind};
+use rustc_lint::LateContext;
+use rustc_middle::{
+    mir::Mutability,
+    ty::{self, Ty, TypeAndMut},
+};
+
+use super::AS_PTR_CAST_MUT;
+
+pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, cast_expr: &Expr<'_>, cast_to: Ty<'_>) {
+    if let ty::RawPtr(ptrty @ TypeAndMut { mutbl: Mutability::Mut, .. }) = cast_to.kind()
+        && let ty::RawPtr(TypeAndMut { mutbl: Mutability::Not, .. }) =
+            cx.typeck_results().node_type(cast_expr.hir_id).kind()
+        && let ExprKind::MethodCall(method_name, receiver, [], _) = cast_expr.peel_blocks().kind
+        && method_name.ident.name == rustc_span::sym::as_ptr
+        && let Some(as_ptr_did) = cx.typeck_results().type_dependent_def_id(cast_expr.peel_blocks().hir_id)
+        && let as_ptr_sig = cx.tcx.fn_sig(as_ptr_did)
+        && let Some(first_param_ty) = as_ptr_sig.skip_binder().inputs().iter().next()
+        && let ty::Ref(_, _, Mutability::Not) = first_param_ty.kind()
+        && let Some(recv) = snippet_opt(cx, receiver.span)
+    {
+        // `as_mut_ptr` might not exist
+        let applicability = Applicability::MaybeIncorrect;
+
+        span_lint_and_sugg(
+            cx,
+            AS_PTR_CAST_MUT,
+            expr.span,
+            &format!("casting the result of `as_ptr` to *{ptrty}"),
+            "replace with",
+            format!("{recv}.as_mut_ptr()"),
+            applicability
+        );
+    }
+}
diff --git a/src/tools/clippy/clippy_lints/src/casts/cast_nan_to_int.rs b/src/tools/clippy/clippy_lints/src/casts/cast_nan_to_int.rs
new file mode 100644
index 000000000000..322dc41b3a19
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/casts/cast_nan_to_int.rs
@@ -0,0 +1,28 @@
+use super::CAST_NAN_TO_INT;
+
+use clippy_utils::consts::{constant, Constant};
+use clippy_utils::diagnostics::span_lint_and_note;
+use rustc_hir::Expr;
+use rustc_lint::LateContext;
+use rustc_middle::ty::Ty;
+
+pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, cast_expr: &Expr<'_>, from_ty: Ty<'_>, to_ty: Ty<'_>) {
+    if from_ty.is_floating_point() && to_ty.is_integral() && is_known_nan(cx, cast_expr) {
+        span_lint_and_note(
+            cx,
+            CAST_NAN_TO_INT,
+            expr.span,
+            &format!("casting a known NaN to {to_ty}"),
+            None,
+            "this always evaluates to 0",
+        );
+    }
+}
+
+fn is_known_nan(cx: &LateContext<'_>, e: &Expr<'_>) -> bool {
+    match constant(cx, cx.typeck_results(), e) {
+        Some((Constant::F64(n), _)) => n.is_nan(),
+        Some((Constant::F32(n), _)) => n.is_nan(),
+        _ => false,
+    }
+}
diff --git a/src/tools/clippy/clippy_lints/src/casts/mod.rs b/src/tools/clippy/clippy_lints/src/casts/mod.rs
index cc5d346b954e..b72c4c772f1c 100644
--- a/src/tools/clippy/clippy_lints/src/casts/mod.rs
+++ b/src/tools/clippy/clippy_lints/src/casts/mod.rs
@@ -1,8 +1,10 @@
+mod as_ptr_cast_mut;
 mod as_underscore;
 mod borrow_as_ptr;
 mod cast_abs_to_unsigned;
 mod cast_enum_constructor;
 mod cast_lossless;
+mod cast_nan_to_int;
 mod cast_possible_truncation;
 mod cast_possible_wrap;
 mod cast_precision_loss;
@@ -569,6 +571,7 @@ declare_clippy_lint! {
     pedantic,
     "borrowing just to cast to a raw pointer"
 }
+
 declare_clippy_lint! {
     /// ### What it does
     /// Checks for a raw slice being cast to a slice pointer
@@ -596,6 +599,54 @@ declare_clippy_lint! {
     "casting a slice created from a pointer and length to a slice pointer"
 }
 
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks for the result of a `&self`-taking `as_ptr` being cast to a mutable pointer
+    ///
+    /// ### Why is this bad?
+    /// Since `as_ptr` takes a `&self`, the pointer won't have write permissions unless interior
+    /// mutability is used, making it unlikely that having it as a mutable pointer is correct.
+    ///
+    /// ### Example
+    /// ```rust
+    /// let string = String::with_capacity(1);
+    /// let ptr = string.as_ptr() as *mut u8;
+    /// unsafe { ptr.write(4) }; // UNDEFINED BEHAVIOUR
+    /// ```
+    /// Use instead:
+    /// ```rust
+    /// let mut string = String::with_capacity(1);
+    /// let ptr = string.as_mut_ptr();
+    /// unsafe { ptr.write(4) };
+    /// ```
+    #[clippy::version = "1.66.0"]
+    pub AS_PTR_CAST_MUT,
+    nursery,
+    "casting the result of the `&self`-taking `as_ptr` to a mutabe pointer"
+}
+
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks for a known NaN float being cast to an integer
+    ///
+    /// ### Why is this bad?
+    /// NaNs are cast into zero, so one could simply use this and make the
+    /// code more readable. The lint could also hint at a programmer error.
+    ///
+    /// ### Example
+    /// ```rust,ignore
+    /// let _: (0.0_f32 / 0.0) as u64;
+    /// ```
+    /// Use instead:
+    /// ```rust,ignore
+    /// let _: = 0_u64;
+    /// ```
+    #[clippy::version = "1.64.0"]
+    pub CAST_NAN_TO_INT,
+    suspicious,
+    "casting a known floating-point NaN into an integer"
+}
+
 pub struct Casts {
     msrv: Option<RustcVersion>,
 }
@@ -627,7 +678,9 @@ impl_lint_pass!(Casts => [
     CAST_ABS_TO_UNSIGNED,
     AS_UNDERSCORE,
     BORROW_AS_PTR,
-    CAST_SLICE_FROM_RAW_PARTS
+    CAST_SLICE_FROM_RAW_PARTS,
+    AS_PTR_CAST_MUT,
+    CAST_NAN_TO_INT,
 ]);
 
 impl<'tcx> LateLintPass<'tcx> for Casts {
@@ -653,6 +706,7 @@ impl<'tcx> LateLintPass<'tcx> for Casts {
                 return;
             }
             cast_slice_from_raw_parts::check(cx, expr, cast_expr, cast_to, self.msrv);
+            as_ptr_cast_mut::check(cx, expr, cast_expr, cast_to);
             fn_to_numeric_cast_any::check(cx, expr, cast_expr, cast_from, cast_to);
             fn_to_numeric_cast::check(cx, expr, cast_expr, cast_from, cast_to);
             fn_to_numeric_cast_with_truncation::check(cx, expr, cast_expr, cast_from, cast_to);
@@ -664,6 +718,7 @@ impl<'tcx> LateLintPass<'tcx> for Casts {
                     cast_precision_loss::check(cx, expr, cast_from, cast_to);
                     cast_sign_loss::check(cx, expr, cast_expr, cast_from, cast_to);
                     cast_abs_to_unsigned::check(cx, expr, cast_expr, cast_from, cast_to, self.msrv);
+                    cast_nan_to_int::check(cx, expr, cast_expr, cast_from, cast_to);
                 }
                 cast_lossless::check(cx, expr, cast_expr, cast_from, cast_to, self.msrv);
                 cast_enum_constructor::check(cx, expr, cast_expr, cast_from);
diff --git a/src/tools/clippy/clippy_lints/src/casts/ptr_as_ptr.rs b/src/tools/clippy/clippy_lints/src/casts/ptr_as_ptr.rs
index c2b9253ec35d..b9509ca656f7 100644
--- a/src/tools/clippy/clippy_lints/src/casts/ptr_as_ptr.rs
+++ b/src/tools/clippy/clippy_lints/src/casts/ptr_as_ptr.rs
@@ -26,7 +26,7 @@ pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, msrv: Option<RustcVer
             (Mutability::Not, Mutability::Not) | (Mutability::Mut, Mutability::Mut));
         // The `U` in `pointer::cast` have to be `Sized`
         // as explained here: https://github.com/rust-lang/rust/issues/60602.
-        if to_pointee_ty.is_sized(cx.tcx.at(expr.span), cx.param_env);
+        if to_pointee_ty.is_sized(cx.tcx, cx.param_env);
         then {
             let mut applicability = Applicability::MachineApplicable;
             let cast_expr_sugg = Sugg::hir_with_applicability(cx, cast_expr, "_", &mut applicability);
diff --git a/src/tools/clippy/clippy_lints/src/casts/unnecessary_cast.rs b/src/tools/clippy/clippy_lints/src/casts/unnecessary_cast.rs
index 21ed7f4844cc..c8596987e4d7 100644
--- a/src/tools/clippy/clippy_lints/src/casts/unnecessary_cast.rs
+++ b/src/tools/clippy/clippy_lints/src/casts/unnecessary_cast.rs
@@ -59,9 +59,6 @@ pub(super) fn check<'tcx>(
                 lint_unnecessary_cast(cx, expr, literal_str, cast_from, cast_to);
                 return false;
             },
-            LitKind::Int(_, LitIntType::Unsuffixed) | LitKind::Float(_, LitFloatType::Unsuffixed) => {
-                return false;
-            },
             LitKind::Int(_, LitIntType::Signed(_) | LitIntType::Unsigned(_))
             | LitKind::Float(_, LitFloatType::Suffixed(_))
                 if cast_from.kind() == cast_to.kind() =>
diff --git a/src/tools/clippy/clippy_lints/src/comparison_chain.rs b/src/tools/clippy/clippy_lints/src/comparison_chain.rs
index a05b41eb3ab5..0fe973b49a35 100644
--- a/src/tools/clippy/clippy_lints/src/comparison_chain.rs
+++ b/src/tools/clippy/clippy_lints/src/comparison_chain.rs
@@ -1,9 +1,10 @@
 use clippy_utils::diagnostics::span_lint_and_help;
 use clippy_utils::ty::implements_trait;
-use clippy_utils::{get_trait_def_id, if_sequence, in_constant, is_else_clause, paths, SpanlessEq};
+use clippy_utils::{if_sequence, in_constant, is_else_clause, SpanlessEq};
 use rustc_hir::{BinOpKind, Expr, ExprKind};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
+use rustc_span::sym;
 
 declare_clippy_lint! {
     /// ### What it does
@@ -106,7 +107,10 @@ impl<'tcx> LateLintPass<'tcx> for ComparisonChain {
 
                 // Check that the type being compared implements `core::cmp::Ord`
                 let ty = cx.typeck_results().expr_ty(lhs1);
-                let is_ord = get_trait_def_id(cx, &paths::ORD).map_or(false, |id| implements_trait(cx, ty, id, &[]));
+                let is_ord = cx
+                    .tcx
+                    .get_diagnostic_item(sym::Ord)
+                    .map_or(false, |id| implements_trait(cx, ty, id, &[]));
 
                 if !is_ord {
                     return;
diff --git a/src/tools/clippy/clippy_lints/src/copy_iterator.rs b/src/tools/clippy/clippy_lints/src/copy_iterator.rs
index 026683f60062..e38f77268530 100644
--- a/src/tools/clippy/clippy_lints/src/copy_iterator.rs
+++ b/src/tools/clippy/clippy_lints/src/copy_iterator.rs
@@ -43,7 +43,7 @@ impl<'tcx> LateLintPass<'tcx> for CopyIterator {
                 of_trait: Some(ref trait_ref),
                 ..
             }) = item.kind;
-            let ty = cx.tcx.type_of(item.def_id);
+            let ty = cx.tcx.type_of(item.owner_id);
             if is_copy(cx, ty);
             if let Some(trait_id) = trait_ref.trait_def_id();
             if cx.tcx.is_diagnostic_item(sym::Iterator, trait_id);
diff --git a/src/tools/clippy/clippy_lints/src/default_numeric_fallback.rs b/src/tools/clippy/clippy_lints/src/default_numeric_fallback.rs
index 3ed9cd36a229..03460689e19a 100644
--- a/src/tools/clippy/clippy_lints/src/default_numeric_fallback.rs
+++ b/src/tools/clippy/clippy_lints/src/default_numeric_fallback.rs
@@ -1,12 +1,12 @@
 use clippy_utils::diagnostics::span_lint_hir_and_then;
-use clippy_utils::numeric_literal;
 use clippy_utils::source::snippet_opt;
+use clippy_utils::{get_parent_node, numeric_literal};
 use if_chain::if_chain;
 use rustc_ast::ast::{LitFloatType, LitIntType, LitKind};
 use rustc_errors::Applicability;
 use rustc_hir::{
     intravisit::{walk_expr, walk_stmt, Visitor},
-    Body, Expr, ExprKind, HirId, Lit, Stmt, StmtKind,
+    Body, Expr, ExprKind, HirId, ItemKind, Lit, Node, Stmt, StmtKind,
 };
 use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_middle::{
@@ -55,22 +55,31 @@ declare_lint_pass!(DefaultNumericFallback => [DEFAULT_NUMERIC_FALLBACK]);
 
 impl<'tcx> LateLintPass<'tcx> for DefaultNumericFallback {
     fn check_body(&mut self, cx: &LateContext<'tcx>, body: &'tcx Body<'_>) {
-        let mut visitor = NumericFallbackVisitor::new(cx);
+        let is_parent_const = if let Some(Node::Item(item)) = get_parent_node(cx.tcx, body.id().hir_id) {
+            matches!(item.kind, ItemKind::Const(..))
+        } else {
+            false
+        };
+        let mut visitor = NumericFallbackVisitor::new(cx, is_parent_const);
         visitor.visit_body(body);
     }
 }
 
 struct NumericFallbackVisitor<'a, 'tcx> {
     /// Stack manages type bound of exprs. The top element holds current expr type.
-    ty_bounds: Vec<TyBound<'tcx>>,
+    ty_bounds: Vec<ExplicitTyBound>,
 
     cx: &'a LateContext<'tcx>,
 }
 
 impl<'a, 'tcx> NumericFallbackVisitor<'a, 'tcx> {
-    fn new(cx: &'a LateContext<'tcx>) -> Self {
+    fn new(cx: &'a LateContext<'tcx>, is_parent_const: bool) -> Self {
         Self {
-            ty_bounds: vec![TyBound::Nothing],
+            ty_bounds: vec![if is_parent_const {
+                ExplicitTyBound(true)
+            } else {
+                ExplicitTyBound(false)
+            }],
             cx,
         }
     }
@@ -79,10 +88,9 @@ impl<'a, 'tcx> NumericFallbackVisitor<'a, 'tcx> {
     fn check_lit(&self, lit: &Lit, lit_ty: Ty<'tcx>, emit_hir_id: HirId) {
         if_chain! {
                 if !in_external_macro(self.cx.sess(), lit.span);
-                if let Some(ty_bound) = self.ty_bounds.last();
+                if matches!(self.ty_bounds.last(), Some(ExplicitTyBound(false)));
                 if matches!(lit.node,
                             LitKind::Int(_, LitIntType::Unsuffixed) | LitKind::Float(_, LitFloatType::Unsuffixed));
-                if !ty_bound.is_numeric();
                 then {
                     let (suffix, is_float) = match lit_ty.kind() {
                         ty::Int(IntTy::I32) => ("i32", false),
@@ -123,7 +131,7 @@ impl<'a, 'tcx> Visitor<'tcx> for NumericFallbackVisitor<'a, 'tcx> {
                 if let Some(fn_sig) = fn_sig_opt(self.cx, func.hir_id) {
                     for (expr, bound) in iter::zip(*args, fn_sig.skip_binder().inputs()) {
                         // Push found arg type, then visit arg.
-                        self.ty_bounds.push(TyBound::Ty(*bound));
+                        self.ty_bounds.push((*bound).into());
                         self.visit_expr(expr);
                         self.ty_bounds.pop();
                     }
@@ -135,7 +143,7 @@ impl<'a, 'tcx> Visitor<'tcx> for NumericFallbackVisitor<'a, 'tcx> {
                 if let Some(def_id) = self.cx.typeck_results().type_dependent_def_id(expr.hir_id) {
                     let fn_sig = self.cx.tcx.fn_sig(def_id).skip_binder();
                     for (expr, bound) in iter::zip(std::iter::once(*receiver).chain(args.iter()), fn_sig.inputs()) {
-                        self.ty_bounds.push(TyBound::Ty(*bound));
+                        self.ty_bounds.push((*bound).into());
                         self.visit_expr(expr);
                         self.ty_bounds.pop();
                     }
@@ -169,7 +177,7 @@ impl<'a, 'tcx> Visitor<'tcx> for NumericFallbackVisitor<'a, 'tcx> {
 
                         // Visit base with no bound.
                         if let Some(base) = base {
-                            self.ty_bounds.push(TyBound::Nothing);
+                            self.ty_bounds.push(ExplicitTyBound(false));
                             self.visit_expr(base);
                             self.ty_bounds.pop();
                         }
@@ -192,15 +200,10 @@ impl<'a, 'tcx> Visitor<'tcx> for NumericFallbackVisitor<'a, 'tcx> {
 
     fn visit_stmt(&mut self, stmt: &'tcx Stmt<'_>) {
         match stmt.kind {
-            StmtKind::Local(local) => {
-                if local.ty.is_some() {
-                    self.ty_bounds.push(TyBound::Any);
-                } else {
-                    self.ty_bounds.push(TyBound::Nothing);
-                }
-            },
+            // we cannot check the exact type since it's a hir::Ty which does not implement `is_numeric`
+            StmtKind::Local(local) => self.ty_bounds.push(ExplicitTyBound(local.ty.is_some())),
 
-            _ => self.ty_bounds.push(TyBound::Nothing),
+            _ => self.ty_bounds.push(ExplicitTyBound(false)),
         }
 
         walk_stmt(self, stmt);
@@ -218,28 +221,18 @@ fn fn_sig_opt<'tcx>(cx: &LateContext<'tcx>, hir_id: HirId) -> Option<PolyFnSig<'
     }
 }
 
+/// Wrapper around a `bool` to make the meaning of the value clearer
 #[derive(Debug, Clone, Copy)]
-enum TyBound<'tcx> {
-    Any,
-    Ty(Ty<'tcx>),
-    Nothing,
-}
+struct ExplicitTyBound(pub bool);
 
-impl<'tcx> TyBound<'tcx> {
-    fn is_numeric(self) -> bool {
-        match self {
-            TyBound::Any => true,
-            TyBound::Ty(t) => t.is_numeric(),
-            TyBound::Nothing => false,
-        }
+impl<'tcx> From<Ty<'tcx>> for ExplicitTyBound {
+    fn from(v: Ty<'tcx>) -> Self {
+        Self(v.is_numeric())
     }
 }
 
-impl<'tcx> From<Option<Ty<'tcx>>> for TyBound<'tcx> {
+impl<'tcx> From<Option<Ty<'tcx>>> for ExplicitTyBound {
     fn from(v: Option<Ty<'tcx>>) -> Self {
-        match v {
-            Some(t) => TyBound::Ty(t),
-            None => TyBound::Nothing,
-        }
+        Self(v.map_or(false, Ty::is_numeric))
     }
 }
diff --git a/src/tools/clippy/clippy_lints/src/default_union_representation.rs b/src/tools/clippy/clippy_lints/src/default_union_representation.rs
index 741edc131960..dec357ab75c3 100644
--- a/src/tools/clippy/clippy_lints/src/default_union_representation.rs
+++ b/src/tools/clippy/clippy_lints/src/default_union_representation.rs
@@ -61,7 +61,7 @@ impl<'tcx> LateLintPass<'tcx> for DefaultUnionRepresentation {
                 None,
                 &format!(
                     "consider annotating `{}` with `#[repr(C)]` to explicitly specify memory layout",
-                    cx.tcx.def_path_str(item.def_id.to_def_id())
+                    cx.tcx.def_path_str(item.owner_id.to_def_id())
                 ),
             );
         }
diff --git a/src/tools/clippy/clippy_lints/src/dereference.rs b/src/tools/clippy/clippy_lints/src/dereference.rs
index 02a16f765b73..a37ee82d4c8a 100644
--- a/src/tools/clippy/clippy_lints/src/dereference.rs
+++ b/src/tools/clippy/clippy_lints/src/dereference.rs
@@ -1,4 +1,5 @@
 use clippy_utils::diagnostics::{span_lint_and_sugg, span_lint_hir_and_then};
+use clippy_utils::mir::{enclosing_mir, expr_local, local_assignments, used_exactly_once, PossibleBorrowerMap};
 use clippy_utils::source::{snippet_with_applicability, snippet_with_context};
 use clippy_utils::sugg::has_enclosing_paren;
 use clippy_utils::ty::{expr_sig, is_copy, peel_mid_ty_refs, ty_sig, variant_of_res};
@@ -11,13 +12,16 @@ use rustc_data_structures::fx::FxIndexMap;
 use rustc_errors::Applicability;
 use rustc_hir::intravisit::{walk_ty, Visitor};
 use rustc_hir::{
-    self as hir, def_id::DefId, BindingAnnotation, Body, BodyId, BorrowKind, Closure, Expr, ExprKind, FnRetTy,
-    GenericArg, HirId, ImplItem, ImplItemKind, Item, ItemKind, Local, MatchSource, Mutability, Node, Pat, PatKind,
-    Path, QPath, TraitItem, TraitItemKind, TyKind, UnOp,
+    self as hir,
+    def_id::{DefId, LocalDefId},
+    BindingAnnotation, Body, BodyId, BorrowKind, Closure, Expr, ExprKind, FnRetTy, GenericArg, HirId, ImplItem,
+    ImplItemKind, Item, ItemKind, Local, MatchSource, Mutability, Node, Pat, PatKind, Path, QPath, TraitItem,
+    TraitItemKind, TyKind, UnOp,
 };
 use rustc_index::bit_set::BitSet;
 use rustc_infer::infer::TyCtxtInferExt;
 use rustc_lint::{LateContext, LateLintPass};
+use rustc_middle::mir::{Rvalue, StatementKind};
 use rustc_middle::ty::adjustment::{Adjust, Adjustment, AutoBorrow, AutoBorrowMutability};
 use rustc_middle::ty::{
     self, Binder, BoundVariableKind, EarlyBinder, FnSig, GenericArgKind, List, ParamTy, PredicateKind,
@@ -25,7 +29,7 @@ use rustc_middle::ty::{
 };
 use rustc_semver::RustcVersion;
 use rustc_session::{declare_tool_lint, impl_lint_pass};
-use rustc_span::{symbol::sym, Span, Symbol, DUMMY_SP};
+use rustc_span::{symbol::sym, Span, Symbol};
 use rustc_trait_selection::infer::InferCtxtExt as _;
 use rustc_trait_selection::traits::{query::evaluate_obligation::InferCtxtExt as _, Obligation, ObligationCause};
 use std::collections::VecDeque;
@@ -141,7 +145,7 @@ declare_clippy_lint! {
     "dereferencing when the compiler would automatically dereference"
 }
 
-impl_lint_pass!(Dereferencing => [
+impl_lint_pass!(Dereferencing<'_> => [
     EXPLICIT_DEREF_METHODS,
     NEEDLESS_BORROW,
     REF_BINDING_TO_REFERENCE,
@@ -149,7 +153,7 @@ impl_lint_pass!(Dereferencing => [
 ]);
 
 #[derive(Default)]
-pub struct Dereferencing {
+pub struct Dereferencing<'tcx> {
     state: Option<(State, StateData)>,
 
     // While parsing a `deref` method call in ufcs form, the path to the function is itself an
@@ -170,11 +174,16 @@ pub struct Dereferencing {
     /// e.g. `m!(x) | Foo::Bar(ref x)`
     ref_locals: FxIndexMap<HirId, Option<RefPat>>,
 
+    /// Stack of (body owner, `PossibleBorrowerMap`) pairs. Used by
+    /// `needless_borrow_impl_arg_position` to determine when a borrowed expression can instead
+    /// be moved.
+    possible_borrowers: Vec<(LocalDefId, PossibleBorrowerMap<'tcx, 'tcx>)>,
+
     // `IntoIterator` for arrays requires Rust 1.53.
     msrv: Option<RustcVersion>,
 }
 
-impl Dereferencing {
+impl<'tcx> Dereferencing<'tcx> {
     #[must_use]
     pub fn new(msrv: Option<RustcVersion>) -> Self {
         Self {
@@ -244,7 +253,7 @@ struct RefPat {
     hir_id: HirId,
 }
 
-impl<'tcx> LateLintPass<'tcx> for Dereferencing {
+impl<'tcx> LateLintPass<'tcx> for Dereferencing<'tcx> {
     #[expect(clippy::too_many_lines)]
     fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
         // Skip path expressions from deref calls. e.g. `Deref::deref(e)`
@@ -278,7 +287,7 @@ impl<'tcx> LateLintPass<'tcx> for Dereferencing {
         match (self.state.take(), kind) {
             (None, kind) => {
                 let expr_ty = typeck.expr_ty(expr);
-                let (position, adjustments) = walk_parents(cx, expr, self.msrv);
+                let (position, adjustments) = walk_parents(cx, &mut self.possible_borrowers, expr, self.msrv);
                 match kind {
                     RefOp::Deref => {
                         if let Position::FieldAccess {
@@ -550,6 +559,12 @@ impl<'tcx> LateLintPass<'tcx> for Dereferencing {
     }
 
     fn check_body_post(&mut self, cx: &LateContext<'tcx>, body: &'tcx Body<'_>) {
+        if self.possible_borrowers.last().map_or(false, |&(local_def_id, _)| {
+            local_def_id == cx.tcx.hir().body_owner_def_id(body.id())
+        }) {
+            self.possible_borrowers.pop();
+        }
+
         if Some(body.id()) == self.current_body {
             for pat in self.ref_locals.drain(..).filter_map(|(_, x)| x) {
                 let replacements = pat.replacements;
@@ -682,6 +697,7 @@ impl Position {
 #[expect(clippy::too_many_lines)]
 fn walk_parents<'tcx>(
     cx: &LateContext<'tcx>,
+    possible_borrowers: &mut Vec<(LocalDefId, PossibleBorrowerMap<'tcx, 'tcx>)>,
     e: &'tcx Expr<'_>,
     msrv: Option<RustcVersion>,
 ) -> (Position, &'tcx [Adjustment<'tcx>]) {
@@ -699,47 +715,47 @@ fn walk_parents<'tcx>(
             },
             Node::Item(&Item {
                 kind: ItemKind::Static(..) | ItemKind::Const(..),
-                def_id,
+                owner_id,
                 span,
                 ..
             })
             | Node::TraitItem(&TraitItem {
                 kind: TraitItemKind::Const(..),
-                def_id,
+                owner_id,
                 span,
                 ..
             })
             | Node::ImplItem(&ImplItem {
                 kind: ImplItemKind::Const(..),
-                def_id,
+                owner_id,
                 span,
                 ..
             }) if span.ctxt() == ctxt => {
-                let ty = cx.tcx.type_of(def_id.def_id);
+                let ty = cx.tcx.type_of(owner_id.def_id);
                 Some(ty_auto_deref_stability(cx, ty, precedence).position_for_result(cx))
             },
 
             Node::Item(&Item {
                 kind: ItemKind::Fn(..),
-                def_id,
+                owner_id,
                 span,
                 ..
             })
             | Node::TraitItem(&TraitItem {
                 kind: TraitItemKind::Fn(..),
-                def_id,
+                owner_id,
                 span,
                 ..
             })
             | Node::ImplItem(&ImplItem {
                 kind: ImplItemKind::Fn(..),
-                def_id,
+                owner_id,
                 span,
                 ..
             }) if span.ctxt() == ctxt => {
                 let output = cx
                     .tcx
-                    .erase_late_bound_regions(cx.tcx.fn_sig(def_id.to_def_id()).output());
+                    .erase_late_bound_regions(cx.tcx.fn_sig(owner_id.to_def_id()).output());
                 Some(ty_auto_deref_stability(cx, output, precedence).position_for_result(cx))
             },
 
@@ -796,7 +812,16 @@ fn walk_parents<'tcx>(
                             Some(hir_ty) => binding_ty_auto_deref_stability(cx, hir_ty, precedence, ty.bound_vars()),
                             None => {
                                 if let ty::Param(param_ty) = ty.skip_binder().kind() {
-                                    needless_borrow_impl_arg_position(cx, parent, i, *param_ty, e, precedence, msrv)
+                                    needless_borrow_impl_arg_position(
+                                        cx,
+                                        possible_borrowers,
+                                        parent,
+                                        i,
+                                        *param_ty,
+                                        e,
+                                        precedence,
+                                        msrv,
+                                    )
                                 } else {
                                     ty_auto_deref_stability(cx, cx.tcx.erase_late_bound_regions(ty), precedence)
                                         .position_for_arg()
@@ -843,7 +868,16 @@ fn walk_parents<'tcx>(
                     args.iter().position(|arg| arg.hir_id == child_id).map(|i| {
                         let ty = cx.tcx.fn_sig(id).skip_binder().inputs()[i + 1];
                         if let ty::Param(param_ty) = ty.kind() {
-                            needless_borrow_impl_arg_position(cx, parent, i + 1, *param_ty, e, precedence, msrv)
+                            needless_borrow_impl_arg_position(
+                                cx,
+                                possible_borrowers,
+                                parent,
+                                i + 1,
+                                *param_ty,
+                                e,
+                                precedence,
+                                msrv,
+                            )
                         } else {
                             ty_auto_deref_stability(
                                 cx,
@@ -956,7 +990,7 @@ fn binding_ty_auto_deref_stability<'tcx>(
                                 cx.typeck_results().node_type(ty.ty.hir_id),
                                 binder_args,
                             ))
-                            .is_sized(cx.tcx.at(DUMMY_SP), cx.param_env.without_caller_bounds()),
+                            .is_sized(cx.tcx, cx.param_env.without_caller_bounds()),
                     )
                 }
             },
@@ -971,7 +1005,7 @@ fn binding_ty_auto_deref_stability<'tcx>(
                         cx.typeck_results().node_type(ty.ty.hir_id),
                         binder_args,
                     ))
-                    .is_sized(cx.tcx.at(DUMMY_SP), cx.param_env.without_caller_bounds()),
+                    .is_sized(cx.tcx, cx.param_env.without_caller_bounds()),
             ),
             TyKind::OpaqueDef(..) | TyKind::Infer | TyKind::Typeof(..) | TyKind::TraitObject(..) | TyKind::Err => {
                 Position::ReborrowStable(precedence)
@@ -1017,8 +1051,10 @@ fn ty_contains_infer(ty: &hir::Ty<'_>) -> bool {
 // If the conditions are met, returns `Some(Position::ImplArg(..))`; otherwise, returns `None`.
 //   The "is copyable" condition is to avoid the case where removing the `&` means `e` would have to
 // be moved, but it cannot be.
+#[expect(clippy::too_many_arguments)]
 fn needless_borrow_impl_arg_position<'tcx>(
     cx: &LateContext<'tcx>,
+    possible_borrowers: &mut Vec<(LocalDefId, PossibleBorrowerMap<'tcx, 'tcx>)>,
     parent: &Expr<'tcx>,
     arg_index: usize,
     param_ty: ParamTy,
@@ -1081,10 +1117,13 @@ fn needless_borrow_impl_arg_position<'tcx>(
     // elements are modified each time `check_referent` is called.
     let mut substs_with_referent_ty = substs_with_expr_ty.to_vec();
 
-    let mut check_referent = |referent| {
+    let mut check_reference_and_referent = |reference, referent| {
         let referent_ty = cx.typeck_results().expr_ty(referent);
 
-        if !is_copy(cx, referent_ty) {
+        if !is_copy(cx, referent_ty)
+            && (referent_ty.has_significant_drop(cx.tcx, cx.param_env)
+                || !referent_used_exactly_once(cx, possible_borrowers, reference))
+        {
             return false;
         }
 
@@ -1125,7 +1164,7 @@ fn needless_borrow_impl_arg_position<'tcx>(
 
     let mut needless_borrow = false;
     while let ExprKind::AddrOf(_, _, referent) = expr.kind {
-        if !check_referent(referent) {
+        if !check_reference_and_referent(expr, referent) {
             break;
         }
         expr = referent;
@@ -1153,6 +1192,36 @@ fn has_ref_mut_self_method(cx: &LateContext<'_>, trait_def_id: DefId) -> bool {
         })
 }
 
+fn referent_used_exactly_once<'tcx>(
+    cx: &LateContext<'tcx>,
+    possible_borrowers: &mut Vec<(LocalDefId, PossibleBorrowerMap<'tcx, 'tcx>)>,
+    reference: &Expr<'tcx>,
+) -> bool {
+    let mir = enclosing_mir(cx.tcx, reference.hir_id);
+    if let Some(local) = expr_local(cx.tcx, reference)
+        && let [location] = *local_assignments(mir, local).as_slice()
+        && let Some(statement) = mir.basic_blocks[location.block].statements.get(location.statement_index)
+        && let StatementKind::Assign(box (_, Rvalue::Ref(_, _, place))) = statement.kind
+        && !place.has_deref()
+    {
+        let body_owner_local_def_id = cx.tcx.hir().enclosing_body_owner(reference.hir_id);
+        if possible_borrowers
+            .last()
+            .map_or(true, |&(local_def_id, _)| local_def_id != body_owner_local_def_id)
+        {
+            possible_borrowers.push((body_owner_local_def_id, PossibleBorrowerMap::new(cx, mir)));
+        }
+        let possible_borrower = &mut possible_borrowers.last_mut().unwrap().1;
+        // If `only_borrowers` were used here, the `copyable_iterator::warn` test would fail. The reason is
+        // that `PossibleBorrowerVisitor::visit_terminator` considers `place.local` a possible borrower of
+        // itself. See the comment in that method for an explanation as to why.
+        possible_borrower.bounded_borrowers(&[local], &[local, place.local], place.local, location)
+            && used_exactly_once(mir, place.local).unwrap_or(false)
+    } else {
+        false
+    }
+}
+
 // Iteratively replaces `param_ty` with `new_ty` in `substs`, and similarly for each resulting
 // projected type that is a type parameter. Returns `false` if replacing the types would have an
 // effect on the function signature beyond substituting `new_ty` for `param_ty`.
@@ -1228,7 +1297,7 @@ impl<'tcx> TyPosition<'tcx> {
     fn position_for_result(self, cx: &LateContext<'tcx>) -> Position {
         match (self.position, self.ty) {
             (Position::ReborrowStable(precedence), Some(ty)) => {
-                Position::DerefStable(precedence, ty.is_sized(cx.tcx.at(DUMMY_SP), cx.param_env))
+                Position::DerefStable(precedence, ty.is_sized(cx.tcx, cx.param_env))
             },
             (position, _) => position,
         }
@@ -1279,7 +1348,7 @@ fn ty_auto_deref_stability<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>, precedenc
             | ty::Tuple(_)
             | ty::Projection(_) => Position::DerefStable(
                 precedence,
-                ty.is_sized(cx.tcx.at(DUMMY_SP), cx.param_env.without_caller_bounds()),
+                ty.is_sized(cx.tcx, cx.param_env.without_caller_bounds()),
             )
             .into(),
         };
@@ -1437,8 +1506,8 @@ fn report<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>, state: State, data
     }
 }
 
-impl Dereferencing {
-    fn check_local_usage<'tcx>(&mut self, cx: &LateContext<'tcx>, e: &Expr<'tcx>, local: HirId) {
+impl<'tcx> Dereferencing<'tcx> {
+    fn check_local_usage(&mut self, cx: &LateContext<'tcx>, e: &Expr<'tcx>, local: HirId) {
         if let Some(outer_pat) = self.ref_locals.get_mut(&local) {
             if let Some(pat) = outer_pat {
                 // Check for auto-deref
diff --git a/src/tools/clippy/clippy_lints/src/derivable_impls.rs b/src/tools/clippy/clippy_lints/src/derivable_impls.rs
index 06ae5abeaeb9..ae8f6b794499 100644
--- a/src/tools/clippy/clippy_lints/src/derivable_impls.rs
+++ b/src/tools/clippy/clippy_lints/src/derivable_impls.rs
@@ -70,7 +70,7 @@ impl<'tcx> LateLintPass<'tcx> for DerivableImpls {
                 self_ty,
                 ..
             }) = item.kind;
-            if !cx.tcx.has_attr(item.def_id.to_def_id(), sym::automatically_derived);
+            if !cx.tcx.has_attr(item.owner_id.to_def_id(), sym::automatically_derived);
             if !item.span.from_expansion();
             if let Some(def_id) = trait_ref.trait_def_id();
             if cx.tcx.is_diagnostic_item(sym::Default, def_id);
@@ -78,7 +78,7 @@ impl<'tcx> LateLintPass<'tcx> for DerivableImpls {
             if let Some(Node::ImplItem(impl_item)) = cx.tcx.hir().find(impl_item_hir);
             if let ImplItemKind::Fn(_, b) = &impl_item.kind;
             if let Body { value: func_expr, .. } = cx.tcx.hir().body(*b);
-            if let Some(adt_def) = cx.tcx.type_of(item.def_id).ty_adt_def();
+            if let Some(adt_def) = cx.tcx.type_of(item.owner_id).ty_adt_def();
             if let attrs = cx.tcx.hir().attrs(item.hir_id());
             if !attrs.iter().any(|attr| attr.doc_str().is_some());
             if let child_attrs = cx.tcx.hir().attrs(impl_item_hir);
diff --git a/src/tools/clippy/clippy_lints/src/derive.rs b/src/tools/clippy/clippy_lints/src/derive.rs
index 3fac93dcc90c..102a02138bc8 100644
--- a/src/tools/clippy/clippy_lints/src/derive.rs
+++ b/src/tools/clippy/clippy_lints/src/derive.rs
@@ -210,8 +210,8 @@ impl<'tcx> LateLintPass<'tcx> for Derive {
             ..
         }) = item.kind
         {
-            let ty = cx.tcx.type_of(item.def_id);
-            let is_automatically_derived = cx.tcx.has_attr(item.def_id.to_def_id(), sym::automatically_derived);
+            let ty = cx.tcx.type_of(item.owner_id);
+            let is_automatically_derived = cx.tcx.has_attr(item.owner_id.to_def_id(), sym::automatically_derived);
 
             check_hash_peq(cx, item.span, trait_ref, ty, is_automatically_derived);
             check_ord_partial_ord(cx, item.span, trait_ref, ty, is_automatically_derived);
@@ -339,10 +339,7 @@ fn check_copy_clone<'tcx>(cx: &LateContext<'tcx>, item: &Item<'_>, trait_ref: &h
         Some(id) if trait_ref.trait_def_id() == Some(id) => id,
         _ => return,
     };
-    let copy_id = match cx.tcx.lang_items().copy_trait() {
-        Some(id) => id,
-        None => return,
-    };
+    let Some(copy_id) = cx.tcx.lang_items().copy_trait() else { return };
     let (ty_adt, ty_subs) = match *ty.kind() {
         // Unions can't derive clone.
         ty::Adt(adt, subs) if !adt.is_union() => (adt, subs),
diff --git a/src/tools/clippy/clippy_lints/src/disallowed_methods.rs b/src/tools/clippy/clippy_lints/src/disallowed_methods.rs
index 1a381f92c031..6ac85606d9c7 100644
--- a/src/tools/clippy/clippy_lints/src/disallowed_methods.rs
+++ b/src/tools/clippy/clippy_lints/src/disallowed_methods.rs
@@ -94,9 +94,8 @@ impl<'tcx> LateLintPass<'tcx> for DisallowedMethods {
         } else {
             path_def_id(cx, expr)
         };
-        let def_id = match uncalled_path.or_else(|| fn_def_id(cx, expr)) {
-            Some(def_id) => def_id,
-            None => return,
+        let Some(def_id) = uncalled_path.or_else(|| fn_def_id(cx, expr)) else {
+            return
         };
         let conf = match self.disallowed.get(&def_id) {
             Some(&index) => &self.conf_disallowed[index],
diff --git a/src/tools/clippy/clippy_lints/src/doc.rs b/src/tools/clippy/clippy_lints/src/doc.rs
index 36dc7e3396b8..daaab79fef9a 100644
--- a/src/tools/clippy/clippy_lints/src/doc.rs
+++ b/src/tools/clippy/clippy_lints/src/doc.rs
@@ -257,17 +257,17 @@ impl<'tcx> LateLintPass<'tcx> for DocMarkdown {
         let headers = check_attrs(cx, &self.valid_idents, attrs);
         match item.kind {
             hir::ItemKind::Fn(ref sig, _, body_id) => {
-                if !(is_entrypoint_fn(cx, item.def_id.to_def_id()) || in_external_macro(cx.tcx.sess, item.span)) {
+                if !(is_entrypoint_fn(cx, item.owner_id.to_def_id()) || in_external_macro(cx.tcx.sess, item.span)) {
                     let body = cx.tcx.hir().body(body_id);
                     let mut fpu = FindPanicUnwrap {
                         cx,
-                        typeck_results: cx.tcx.typeck(item.def_id.def_id),
+                        typeck_results: cx.tcx.typeck(item.owner_id.def_id),
                         panic_span: None,
                     };
                     fpu.visit_expr(body.value);
                     lint_for_missing_headers(
                         cx,
-                        item.def_id.def_id,
+                        item.owner_id.def_id,
                         item.span,
                         sig,
                         headers,
@@ -304,7 +304,7 @@ impl<'tcx> LateLintPass<'tcx> for DocMarkdown {
         let headers = check_attrs(cx, &self.valid_idents, attrs);
         if let hir::TraitItemKind::Fn(ref sig, ..) = item.kind {
             if !in_external_macro(cx.tcx.sess, item.span) {
-                lint_for_missing_headers(cx, item.def_id.def_id, item.span, sig, headers, None, None);
+                lint_for_missing_headers(cx, item.owner_id.def_id, item.span, sig, headers, None, None);
             }
         }
     }
@@ -319,13 +319,13 @@ impl<'tcx> LateLintPass<'tcx> for DocMarkdown {
             let body = cx.tcx.hir().body(body_id);
             let mut fpu = FindPanicUnwrap {
                 cx,
-                typeck_results: cx.tcx.typeck(item.def_id.def_id),
+                typeck_results: cx.tcx.typeck(item.owner_id.def_id),
                 panic_span: None,
             };
             fpu.visit_expr(body.value);
             lint_for_missing_headers(
                 cx,
-                item.def_id.def_id,
+                item.owner_id.def_id,
                 item.span,
                 sig,
                 headers,
@@ -345,7 +345,7 @@ fn lint_for_missing_headers<'tcx>(
     body_id: Option<hir::BodyId>,
     panic_span: Option<Span>,
 ) {
-    if !cx.access_levels.is_exported(def_id) {
+    if !cx.effective_visibilities.is_exported(def_id) {
         return; // Private functions do not require doc comments
     }
 
@@ -691,6 +691,7 @@ fn check_code(cx: &LateContext<'_>, text: &str, edition: Edition, span: Span) {
                     false,
                     None,
                     false,
+                    false,
                 );
                 let handler = Handler::with_emitter(false, None, Box::new(emitter));
                 let sess = ParseSess::with_span_handler(handler, sm);
diff --git a/src/tools/clippy/clippy_lints/src/empty_enum.rs b/src/tools/clippy/clippy_lints/src/empty_enum.rs
index bbebc0244141..0570c2a10138 100644
--- a/src/tools/clippy/clippy_lints/src/empty_enum.rs
+++ b/src/tools/clippy/clippy_lints/src/empty_enum.rs
@@ -49,7 +49,7 @@ impl<'tcx> LateLintPass<'tcx> for EmptyEnum {
         }
 
         if let ItemKind::Enum(..) = item.kind {
-            let ty = cx.tcx.type_of(item.def_id);
+            let ty = cx.tcx.type_of(item.owner_id);
             let adt = ty.ty_adt_def().expect("already checked whether this is an enum");
             if adt.variants().is_empty() {
                 span_lint_and_help(
diff --git a/src/tools/clippy/clippy_lints/src/entry.rs b/src/tools/clippy/clippy_lints/src/entry.rs
index 9c834cf01448..b44e62435881 100644
--- a/src/tools/clippy/clippy_lints/src/entry.rs
+++ b/src/tools/clippy/clippy_lints/src/entry.rs
@@ -65,28 +65,24 @@ declare_lint_pass!(HashMapPass => [MAP_ENTRY]);
 impl<'tcx> LateLintPass<'tcx> for HashMapPass {
     #[expect(clippy::too_many_lines)]
     fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
-        let (cond_expr, then_expr, else_expr) = match higher::If::hir(expr) {
-            Some(higher::If { cond, then, r#else }) => (cond, then, r#else),
-            _ => return,
+        let Some(higher::If { cond: cond_expr, then: then_expr, r#else: else_expr }) = higher::If::hir(expr) else {
+            return
         };
 
-        let (map_ty, contains_expr) = match try_parse_contains(cx, cond_expr) {
-            Some(x) => x,
-            None => return,
+        let Some((map_ty, contains_expr)) = try_parse_contains(cx, cond_expr) else {
+            return
         };
 
-        let then_search = match find_insert_calls(cx, &contains_expr, then_expr) {
-            Some(x) => x,
-            None => return,
+        let Some(then_search) = find_insert_calls(cx, &contains_expr, then_expr) else {
+            return
         };
 
         let mut app = Applicability::MachineApplicable;
         let map_str = snippet_with_context(cx, contains_expr.map.span, contains_expr.call_ctxt, "..", &mut app).0;
         let key_str = snippet_with_context(cx, contains_expr.key.span, contains_expr.call_ctxt, "..", &mut app).0;
         let sugg = if let Some(else_expr) = else_expr {
-            let else_search = match find_insert_calls(cx, &contains_expr, else_expr) {
-                Some(search) => search,
-                None => return,
+            let Some(else_search) = find_insert_calls(cx, &contains_expr, else_expr) else {
+                return;
             };
 
             if then_search.edits.is_empty() && else_search.edits.is_empty() {
diff --git a/src/tools/clippy/clippy_lints/src/enum_variants.rs b/src/tools/clippy/clippy_lints/src/enum_variants.rs
index b019d07d53d1..223545fa7984 100644
--- a/src/tools/clippy/clippy_lints/src/enum_variants.rs
+++ b/src/tools/clippy/clippy_lints/src/enum_variants.rs
@@ -265,7 +265,7 @@ impl LateLintPass<'_> for EnumVariantNames {
                     }
                     // The `module_name_repetitions` lint should only trigger if the item has the module in its
                     // name. Having the same name is accepted.
-                    if cx.tcx.visibility(item.def_id).is_public() && item_camel.len() > mod_camel.len() {
+                    if cx.tcx.visibility(item.owner_id).is_public() && item_camel.len() > mod_camel.len() {
                         let matching = count_match_start(mod_camel, &item_camel);
                         let rmatching = count_match_end(mod_camel, &item_camel);
                         let nchars = mod_camel.chars().count();
@@ -296,7 +296,7 @@ impl LateLintPass<'_> for EnumVariantNames {
             }
         }
         if let ItemKind::Enum(ref def, _) = item.kind {
-            if !(self.avoid_breaking_exported_api && cx.access_levels.is_exported(item.def_id.def_id)) {
+            if !(self.avoid_breaking_exported_api && cx.effective_visibilities.is_exported(item.owner_id.def_id)) {
                 check_variant(cx, self.threshold, def, item_name, item.span);
             }
         }
diff --git a/src/tools/clippy/clippy_lints/src/escape.rs b/src/tools/clippy/clippy_lints/src/escape.rs
index c9a8307eba4f..7f1a4c4beb1f 100644
--- a/src/tools/clippy/clippy_lints/src/escape.rs
+++ b/src/tools/clippy/clippy_lints/src/escape.rs
@@ -88,7 +88,7 @@ impl<'tcx> LateLintPass<'tcx> for BoxedLocal {
                         // be sure we have `self` parameter in this function
                         if trait_item.kind == (AssocItemKind::Fn { has_self: true }) {
                             trait_self_ty = Some(
-                                TraitRef::identity(cx.tcx, trait_item.id.def_id.to_def_id())
+                                TraitRef::identity(cx.tcx, trait_item.id.owner_id.to_def_id())
                                     .self_ty()
                                     .skip_binder(),
                             );
diff --git a/src/tools/clippy/clippy_lints/src/eta_reduction.rs b/src/tools/clippy/clippy_lints/src/eta_reduction.rs
index 3732410e71e5..7b9786d7e570 100644
--- a/src/tools/clippy/clippy_lints/src/eta_reduction.rs
+++ b/src/tools/clippy/clippy_lints/src/eta_reduction.rs
@@ -213,9 +213,8 @@ fn check_sig<'tcx>(cx: &LateContext<'tcx>, closure_ty: Ty<'tcx>, call_ty: Ty<'tc
     if !closure_ty.has_late_bound_regions() {
         return true;
     }
-    let substs = match closure_ty.kind() {
-        ty::Closure(_, substs) => substs,
-        _ => return false,
+    let ty::Closure(_, substs) = closure_ty.kind() else {
+        return false;
     };
     let closure_sig = cx.tcx.signature_unclosure(substs.as_closure().sig(), Unsafety::Normal);
     cx.tcx.erase_late_bound_regions(closure_sig) == cx.tcx.erase_late_bound_regions(call_sig)
diff --git a/src/tools/clippy/clippy_lints/src/exhaustive_items.rs b/src/tools/clippy/clippy_lints/src/exhaustive_items.rs
index be6242bd20b8..1fece5d1c480 100644
--- a/src/tools/clippy/clippy_lints/src/exhaustive_items.rs
+++ b/src/tools/clippy/clippy_lints/src/exhaustive_items.rs
@@ -73,7 +73,7 @@ impl LateLintPass<'_> for ExhaustiveItems {
     fn check_item(&mut self, cx: &LateContext<'_>, item: &Item<'_>) {
         if_chain! {
             if let ItemKind::Enum(..) | ItemKind::Struct(..) = item.kind;
-            if cx.access_levels.is_exported(item.def_id.def_id);
+            if cx.effective_visibilities.is_exported(item.owner_id.def_id);
             let attrs = cx.tcx.hir().attrs(item.hir_id());
             if !attrs.iter().any(|a| a.has_name(sym::non_exhaustive));
             then {
diff --git a/src/tools/clippy/clippy_lints/src/fallible_impl_from.rs b/src/tools/clippy/clippy_lints/src/fallible_impl_from.rs
index ef24a5d06ad0..0a633f242a5f 100644
--- a/src/tools/clippy/clippy_lints/src/fallible_impl_from.rs
+++ b/src/tools/clippy/clippy_lints/src/fallible_impl_from.rs
@@ -55,7 +55,7 @@ impl<'tcx> LateLintPass<'tcx> for FallibleImplFrom {
         // check for `impl From<???> for ..`
         if_chain! {
             if let hir::ItemKind::Impl(impl_) = &item.kind;
-            if let Some(impl_trait_ref) = cx.tcx.impl_trait_ref(item.def_id);
+            if let Some(impl_trait_ref) = cx.tcx.impl_trait_ref(item.owner_id);
             if cx.tcx.is_diagnostic_item(sym::From, impl_trait_ref.def_id);
             then {
                 lint_impl_body(cx, item.span, impl_.items);
@@ -107,7 +107,7 @@ fn lint_impl_body<'tcx>(cx: &LateContext<'tcx>, impl_span: Span, impl_items: &[h
                 let body = cx.tcx.hir().body(body_id);
                 let mut fpu = FindPanicUnwrap {
                     lcx: cx,
-                    typeck_results: cx.tcx.typeck(impl_item.id.def_id.def_id),
+                    typeck_results: cx.tcx.typeck(impl_item.id.owner_id.def_id),
                     result: Vec::new(),
                 };
                 fpu.visit_expr(body.value);
diff --git a/src/tools/clippy/clippy_lints/src/format_args.rs b/src/tools/clippy/clippy_lints/src/format_args.rs
index 99bef62f8143..f0fe845d3303 100644
--- a/src/tools/clippy/clippy_lints/src/format_args.rs
+++ b/src/tools/clippy/clippy_lints/src/format_args.rs
@@ -1,8 +1,10 @@
 use clippy_utils::diagnostics::{span_lint_and_sugg, span_lint_and_then};
 use clippy_utils::macros::FormatParamKind::{Implicit, Named, Numbered, Starred};
-use clippy_utils::macros::{is_format_macro, FormatArgsExpn, FormatParam, FormatParamUsage};
+use clippy_utils::macros::{
+    is_format_macro, is_panic, root_macro_call, Count, FormatArg, FormatArgsExpn, FormatParam, FormatParamUsage,
+};
 use clippy_utils::source::snippet_opt;
-use clippy_utils::ty::implements_trait;
+use clippy_utils::ty::{implements_trait, is_type_diagnostic_item};
 use clippy_utils::{is_diag_trait_item, meets_msrv, msrvs};
 use if_chain::if_chain;
 use itertools::Itertools;
@@ -13,6 +15,8 @@ use rustc_middle::ty::adjustment::{Adjust, Adjustment};
 use rustc_middle::ty::Ty;
 use rustc_semver::RustcVersion;
 use rustc_session::{declare_tool_lint, impl_lint_pass};
+use rustc_span::def_id::DefId;
+use rustc_span::edition::Edition::Edition2021;
 use rustc_span::{sym, ExpnData, ExpnKind, Span, Symbol};
 
 declare_clippy_lint! {
@@ -115,7 +119,43 @@ declare_clippy_lint! {
     "using non-inlined variables in `format!` calls"
 }
 
-impl_lint_pass!(FormatArgs => [FORMAT_IN_FORMAT_ARGS, UNINLINED_FORMAT_ARGS, TO_STRING_IN_FORMAT_ARGS]);
+declare_clippy_lint! {
+    /// ### What it does
+    /// Detects [formatting parameters] that have no effect on the output of
+    /// `format!()`, `println!()` or similar macros.
+    ///
+    /// ### Why is this bad?
+    /// Shorter format specifiers are easier to read, it may also indicate that
+    /// an expected formatting operation such as adding padding isn't happening.
+    ///
+    /// ### Example
+    /// ```rust
+    /// println!("{:.}", 1.0);
+    ///
+    /// println!("not padded: {:5}", format_args!("..."));
+    /// ```
+    /// Use instead:
+    /// ```rust
+    /// println!("{}", 1.0);
+    ///
+    /// println!("not padded: {}", format_args!("..."));
+    /// // OR
+    /// println!("padded: {:5}", format!("..."));
+    /// ```
+    ///
+    /// [formatting parameters]: https://doc.rust-lang.org/std/fmt/index.html#formatting-parameters
+    #[clippy::version = "1.66.0"]
+    pub UNUSED_FORMAT_SPECS,
+    complexity,
+    "use of a format specifier that has no effect"
+}
+
+impl_lint_pass!(FormatArgs => [
+    FORMAT_IN_FORMAT_ARGS,
+    TO_STRING_IN_FORMAT_ARGS,
+    UNINLINED_FORMAT_ARGS,
+    UNUSED_FORMAT_SPECS,
+]);
 
 pub struct FormatArgs {
     msrv: Option<RustcVersion>,
@@ -130,27 +170,26 @@ impl FormatArgs {
 
 impl<'tcx> LateLintPass<'tcx> for FormatArgs {
     fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) {
-        if_chain! {
-            if let Some(format_args) = FormatArgsExpn::parse(cx, expr);
-            let expr_expn_data = expr.span.ctxt().outer_expn_data();
-            let outermost_expn_data = outermost_expn_data(expr_expn_data);
-            if let Some(macro_def_id) = outermost_expn_data.macro_def_id;
-            if is_format_macro(cx, macro_def_id);
-            if let ExpnKind::Macro(_, name) = outermost_expn_data.kind;
-            then {
-                for arg in &format_args.args {
-                    if !arg.format.is_default() {
-                        continue;
-                    }
-                    if is_aliased(&format_args, arg.param.value.hir_id) {
-                        continue;
-                    }
-                    check_format_in_format_args(cx, outermost_expn_data.call_site, name, arg.param.value);
-                    check_to_string_in_format_args(cx, name, arg.param.value);
+        if let Some(format_args) = FormatArgsExpn::parse(cx, expr)
+            && let expr_expn_data = expr.span.ctxt().outer_expn_data()
+            && let outermost_expn_data = outermost_expn_data(expr_expn_data)
+            && let Some(macro_def_id) = outermost_expn_data.macro_def_id
+            && is_format_macro(cx, macro_def_id)
+            && let ExpnKind::Macro(_, name) = outermost_expn_data.kind
+        {
+            for arg in &format_args.args {
+                check_unused_format_specifier(cx, arg);
+                if !arg.format.is_default() {
+                    continue;
                 }
-                if meets_msrv(self.msrv, msrvs::FORMAT_ARGS_CAPTURE) {
-                    check_uninlined_args(cx, &format_args, outermost_expn_data.call_site);
+                if is_aliased(&format_args, arg.param.value.hir_id) {
+                    continue;
                 }
+                check_format_in_format_args(cx, outermost_expn_data.call_site, name, arg.param.value);
+                check_to_string_in_format_args(cx, name, arg.param.value);
+            }
+            if meets_msrv(self.msrv, msrvs::FORMAT_ARGS_CAPTURE) {
+                check_uninlined_args(cx, &format_args, outermost_expn_data.call_site, macro_def_id);
             }
         }
     }
@@ -158,10 +197,84 @@ impl<'tcx> LateLintPass<'tcx> for FormatArgs {
     extract_msrv_attr!(LateContext);
 }
 
-fn check_uninlined_args(cx: &LateContext<'_>, args: &FormatArgsExpn<'_>, call_site: Span) {
+fn check_unused_format_specifier(cx: &LateContext<'_>, arg: &FormatArg<'_>) {
+    let param_ty = cx.typeck_results().expr_ty(arg.param.value).peel_refs();
+
+    if let Count::Implied(Some(mut span)) = arg.format.precision
+        && !span.is_empty()
+    {
+        span_lint_and_then(
+            cx,
+            UNUSED_FORMAT_SPECS,
+            span,
+            "empty precision specifier has no effect",
+            |diag| {
+                if param_ty.is_floating_point() {
+                    diag.note("a precision specifier is not required to format floats");
+                }
+
+                if arg.format.is_default() {
+                    // If there's no other specifiers remove the `:` too
+                    span = arg.format_span();
+                }
+
+                diag.span_suggestion_verbose(span, "remove the `.`", "", Applicability::MachineApplicable);
+            },
+        );
+    }
+
+    if is_type_diagnostic_item(cx, param_ty, sym::Arguments) && !arg.format.is_default_for_trait() {
+        span_lint_and_then(
+            cx,
+            UNUSED_FORMAT_SPECS,
+            arg.span,
+            "format specifiers have no effect on `format_args!()`",
+            |diag| {
+                let mut suggest_format = |spec, span| {
+                    let message = format!("for the {spec} to apply consider using `format!()`");
+
+                    if let Some(mac_call) = root_macro_call(arg.param.value.span)
+                        && cx.tcx.is_diagnostic_item(sym::format_args_macro, mac_call.def_id)
+                        && arg.span.eq_ctxt(mac_call.span)
+                    {
+                        diag.span_suggestion(
+                            cx.sess().source_map().span_until_char(mac_call.span, '!'),
+                            message,
+                            "format",
+                            Applicability::MaybeIncorrect,
+                        );
+                    } else if let Some(span) = span {
+                        diag.span_help(span, message);
+                    }
+                };
+
+                if !arg.format.width.is_implied() {
+                    suggest_format("width", arg.format.width.span());
+                }
+
+                if !arg.format.precision.is_implied() {
+                    suggest_format("precision", arg.format.precision.span());
+                }
+
+                diag.span_suggestion_verbose(
+                    arg.format_span(),
+                    "if the current behavior is intentional, remove the format specifiers",
+                    "",
+                    Applicability::MaybeIncorrect,
+                );
+            },
+        );
+    }
+}
+
+fn check_uninlined_args(cx: &LateContext<'_>, args: &FormatArgsExpn<'_>, call_site: Span, def_id: DefId) {
     if args.format_string.span.from_expansion() {
         return;
     }
+    if call_site.edition() < Edition2021 && is_panic(cx, def_id) {
+        // panic! before 2021 edition considers a single string argument as non-format
+        return;
+    }
 
     let mut fixes = Vec::new();
     // If any of the arguments are referenced by an index number,
@@ -248,7 +361,7 @@ fn check_format_in_format_args(
 fn check_to_string_in_format_args(cx: &LateContext<'_>, name: Symbol, value: &Expr<'_>) {
     if_chain! {
         if !value.span.from_expansion();
-        if let ExprKind::MethodCall(_, receiver, [], _) = value.kind;
+        if let ExprKind::MethodCall(_, receiver, [], to_string_span) = value.kind;
         if let Some(method_def_id) = cx.typeck_results().type_dependent_def_id(value.hir_id);
         if is_diag_trait_item(cx, method_def_id, sym::ToString);
         let receiver_ty = cx.typeck_results().expr_ty(receiver);
@@ -264,7 +377,7 @@ fn check_to_string_in_format_args(cx: &LateContext<'_>, name: Symbol, value: &Ex
                 span_lint_and_sugg(
                     cx,
                     TO_STRING_IN_FORMAT_ARGS,
-                    value.span.with_lo(receiver.span.hi()),
+                    to_string_span.with_lo(receiver.span.hi()),
                     &format!(
                         "`to_string` applied to a type that implements `Display` in `{name}!` args"
                     ),
diff --git a/src/tools/clippy/clippy_lints/src/from_over_into.rs b/src/tools/clippy/clippy_lints/src/from_over_into.rs
index 5d25c1d06341..8b24a4962fb2 100644
--- a/src/tools/clippy/clippy_lints/src/from_over_into.rs
+++ b/src/tools/clippy/clippy_lints/src/from_over_into.rs
@@ -1,11 +1,19 @@
-use clippy_utils::diagnostics::span_lint_and_help;
-use clippy_utils::{meets_msrv, msrvs};
-use if_chain::if_chain;
-use rustc_hir as hir;
+use clippy_utils::diagnostics::span_lint_and_then;
+use clippy_utils::macros::span_is_local;
+use clippy_utils::source::snippet_opt;
+use clippy_utils::{meets_msrv, msrvs, path_def_id};
+use rustc_errors::Applicability;
+use rustc_hir::intravisit::{walk_path, Visitor};
+use rustc_hir::{
+    GenericArg, GenericArgs, HirId, Impl, ImplItemKind, ImplItemRef, Item, ItemKind, PatKind, Path, PathSegment, Ty,
+    TyKind,
+};
 use rustc_lint::{LateContext, LateLintPass};
+use rustc_middle::hir::nested_filter::OnlyBodies;
 use rustc_semver::RustcVersion;
 use rustc_session::{declare_tool_lint, impl_lint_pass};
-use rustc_span::symbol::sym;
+use rustc_span::symbol::{kw, sym};
+use rustc_span::{Span, Symbol};
 
 declare_clippy_lint! {
     /// ### What it does
@@ -54,28 +62,152 @@ impl FromOverInto {
 impl_lint_pass!(FromOverInto => [FROM_OVER_INTO]);
 
 impl<'tcx> LateLintPass<'tcx> for FromOverInto {
-    fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx hir::Item<'_>) {
-        if !meets_msrv(self.msrv, msrvs::RE_REBALANCING_COHERENCE) {
+    fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'_>) {
+        if !meets_msrv(self.msrv, msrvs::RE_REBALANCING_COHERENCE) || !span_is_local(item.span) {
             return;
         }
 
-        if_chain! {
-            if let hir::ItemKind::Impl{ .. } = &item.kind;
-            if let Some(impl_trait_ref) = cx.tcx.impl_trait_ref(item.def_id);
-            if cx.tcx.is_diagnostic_item(sym::Into, impl_trait_ref.def_id);
+        if let ItemKind::Impl(Impl {
+            of_trait: Some(hir_trait_ref),
+            self_ty,
+            items: [impl_item_ref],
+            ..
+        }) = item.kind
+            && let Some(into_trait_seg) = hir_trait_ref.path.segments.last()
+            // `impl Into<target_ty> for self_ty`
+            && let Some(GenericArgs { args: [GenericArg::Type(target_ty)], .. }) = into_trait_seg.args
+            && let Some(middle_trait_ref) = cx.tcx.impl_trait_ref(item.owner_id)
+            && cx.tcx.is_diagnostic_item(sym::Into, middle_trait_ref.def_id)
+        {
+            span_lint_and_then(
+                cx,
+                FROM_OVER_INTO,
+                cx.tcx.sess.source_map().guess_head_span(item.span),
+                "an implementation of `From` is preferred since it gives you `Into<_>` for free where the reverse isn't true",
+                |diag| {
+                    // If the target type is likely foreign mention the orphan rules as it's a common source of confusion
+                    if path_def_id(cx, target_ty.peel_refs()).map_or(true, |id| !id.is_local()) {
+                        diag.help(
+                            "`impl From<Local> for Foreign` is allowed by the orphan rules, for more information see\n\
+                            https://doc.rust-lang.org/reference/items/implementations.html#trait-implementation-coherence"
+                        );
+                    }
 
-            then {
-                span_lint_and_help(
-                    cx,
-                    FROM_OVER_INTO,
-                    cx.tcx.sess.source_map().guess_head_span(item.span),
-                    "an implementation of `From` is preferred since it gives you `Into<_>` for free where the reverse isn't true",
-                    None,
-                    &format!("consider to implement `From<{}>` instead", impl_trait_ref.self_ty()),
-                );
-            }
+                    let message = format!("replace the `Into` implentation with `From<{}>`", middle_trait_ref.self_ty());
+                    if let Some(suggestions) = convert_to_from(cx, into_trait_seg, target_ty, self_ty, impl_item_ref) {
+                        diag.multipart_suggestion(message, suggestions, Applicability::MachineApplicable);
+                    } else {
+                        diag.help(message);
+                    }
+                },
+            );
         }
     }
 
     extract_msrv_attr!(LateContext);
 }
+
+/// Finds the occurences of `Self` and `self`
+struct SelfFinder<'a, 'tcx> {
+    cx: &'a LateContext<'tcx>,
+    /// Occurences of `Self`
+    upper: Vec<Span>,
+    /// Occurences of `self`
+    lower: Vec<Span>,
+    /// If any of the `self`/`Self` usages were from an expansion, or the body contained a binding
+    /// already named `val`
+    invalid: bool,
+}
+
+impl<'a, 'tcx> Visitor<'tcx> for SelfFinder<'a, 'tcx> {
+    type NestedFilter = OnlyBodies;
+
+    fn nested_visit_map(&mut self) -> Self::Map {
+        self.cx.tcx.hir()
+    }
+
+    fn visit_path(&mut self, path: &'tcx Path<'tcx>, _id: HirId) {
+        for segment in path.segments {
+            match segment.ident.name {
+                kw::SelfLower => self.lower.push(segment.ident.span),
+                kw::SelfUpper => self.upper.push(segment.ident.span),
+                _ => continue,
+            }
+        }
+
+        self.invalid |= path.span.from_expansion();
+        if !self.invalid {
+            walk_path(self, path);
+        }
+    }
+
+    fn visit_name(&mut self, name: Symbol) {
+        if name == sym::val {
+            self.invalid = true;
+        }
+    }
+}
+
+fn convert_to_from(
+    cx: &LateContext<'_>,
+    into_trait_seg: &PathSegment<'_>,
+    target_ty: &Ty<'_>,
+    self_ty: &Ty<'_>,
+    impl_item_ref: &ImplItemRef,
+) -> Option<Vec<(Span, String)>> {
+    let impl_item = cx.tcx.hir().impl_item(impl_item_ref.id);
+    let ImplItemKind::Fn(ref sig, body_id) = impl_item.kind else { return None };
+    let body = cx.tcx.hir().body(body_id);
+    let [input] = body.params else { return None };
+    let PatKind::Binding(.., self_ident, None) = input.pat.kind else { return None };
+
+    let from = snippet_opt(cx, self_ty.span)?;
+    let into = snippet_opt(cx, target_ty.span)?;
+
+    let mut suggestions = vec![
+        // impl Into<T> for U  ->  impl From<T> for U
+        //      ~~~~                    ~~~~
+        (into_trait_seg.ident.span, String::from("From")),
+        // impl Into<T> for U  ->  impl Into<U> for U
+        //           ~                       ~
+        (target_ty.span, from.clone()),
+        // impl Into<T> for U  ->  impl Into<T> for T
+        //                  ~                       ~
+        (self_ty.span, into),
+        // fn into(self) -> T  ->  fn from(self) -> T
+        //    ~~~~                    ~~~~
+        (impl_item.ident.span, String::from("from")),
+        // fn into([mut] self) -> T  ->  fn into([mut] v: T) -> T
+        //               ~~~~                          ~~~~
+        (self_ident.span, format!("val: {from}")),
+        // fn into(self) -> T  ->  fn into(self) -> Self
+        //                  ~                       ~~~~
+        (sig.decl.output.span(), String::from("Self")),
+    ];
+
+    let mut finder = SelfFinder {
+        cx,
+        upper: Vec::new(),
+        lower: Vec::new(),
+        invalid: false,
+    };
+    finder.visit_expr(body.value);
+
+    if finder.invalid {
+        return None;
+    }
+
+    // don't try to replace e.g. `Self::default()` with `&[T]::default()`
+    if !finder.upper.is_empty() && !matches!(self_ty.kind, TyKind::Path(_)) {
+        return None;
+    }
+
+    for span in finder.upper {
+        suggestions.push((span, from.clone()));
+    }
+    for span in finder.lower {
+        suggestions.push((span, String::from("val")));
+    }
+
+    Some(suggestions)
+}
diff --git a/src/tools/clippy/clippy_lints/src/functions/must_use.rs b/src/tools/clippy/clippy_lints/src/functions/must_use.rs
index d263804f32cf..bff69f915184 100644
--- a/src/tools/clippy/clippy_lints/src/functions/must_use.rs
+++ b/src/tools/clippy/clippy_lints/src/functions/must_use.rs
@@ -7,14 +7,14 @@ use rustc_middle::{
     lint::in_external_macro,
     ty::{self, Ty},
 };
-use rustc_span::{sym, Span};
+use rustc_span::{sym, Span, Symbol};
 
 use clippy_utils::attrs::is_proc_macro;
 use clippy_utils::diagnostics::{span_lint_and_help, span_lint_and_then};
 use clippy_utils::source::snippet_opt;
 use clippy_utils::ty::is_must_use_ty;
 use clippy_utils::visitors::for_each_expr;
-use clippy_utils::{match_def_path, return_ty, trait_ref_of_method};
+use clippy_utils::{return_ty, trait_ref_of_method};
 
 use core::ops::ControlFlow;
 
@@ -22,9 +22,9 @@ use super::{DOUBLE_MUST_USE, MUST_USE_CANDIDATE, MUST_USE_UNIT};
 
 pub(super) fn check_item<'tcx>(cx: &LateContext<'tcx>, item: &'tcx hir::Item<'_>) {
     let attrs = cx.tcx.hir().attrs(item.hir_id());
-    let attr = cx.tcx.get_attr(item.def_id.to_def_id(), sym::must_use);
+    let attr = cx.tcx.get_attr(item.owner_id.to_def_id(), sym::must_use);
     if let hir::ItemKind::Fn(ref sig, _generics, ref body_id) = item.kind {
-        let is_public = cx.access_levels.is_exported(item.def_id.def_id);
+        let is_public = cx.effective_visibilities.is_exported(item.owner_id.def_id);
         let fn_header_span = item.span.with_hi(sig.decl.output.span().hi());
         if let Some(attr) = attr {
             check_needless_must_use(cx, sig.decl, item.hir_id(), item.span, fn_header_span, attr);
@@ -34,7 +34,7 @@ pub(super) fn check_item<'tcx>(cx: &LateContext<'tcx>, item: &'tcx hir::Item<'_>
                 sig.decl,
                 cx.tcx.hir().body(*body_id),
                 item.span,
-                item.def_id.def_id,
+                item.owner_id.def_id,
                 item.span.with_hi(sig.decl.output.span().hi()),
                 "this function could have a `#[must_use]` attribute",
             );
@@ -44,20 +44,20 @@ pub(super) fn check_item<'tcx>(cx: &LateContext<'tcx>, item: &'tcx hir::Item<'_>
 
 pub(super) fn check_impl_item<'tcx>(cx: &LateContext<'tcx>, item: &'tcx hir::ImplItem<'_>) {
     if let hir::ImplItemKind::Fn(ref sig, ref body_id) = item.kind {
-        let is_public = cx.access_levels.is_exported(item.def_id.def_id);
+        let is_public = cx.effective_visibilities.is_exported(item.owner_id.def_id);
         let fn_header_span = item.span.with_hi(sig.decl.output.span().hi());
         let attrs = cx.tcx.hir().attrs(item.hir_id());
-        let attr = cx.tcx.get_attr(item.def_id.to_def_id(), sym::must_use);
+        let attr = cx.tcx.get_attr(item.owner_id.to_def_id(), sym::must_use);
         if let Some(attr) = attr {
             check_needless_must_use(cx, sig.decl, item.hir_id(), item.span, fn_header_span, attr);
-        } else if is_public && !is_proc_macro(cx.sess(), attrs) && trait_ref_of_method(cx, item.def_id.def_id).is_none()
+        } else if is_public && !is_proc_macro(cx.sess(), attrs) && trait_ref_of_method(cx, item.owner_id.def_id).is_none()
         {
             check_must_use_candidate(
                 cx,
                 sig.decl,
                 cx.tcx.hir().body(*body_id),
                 item.span,
-                item.def_id.def_id,
+                item.owner_id.def_id,
                 item.span.with_hi(sig.decl.output.span().hi()),
                 "this method could have a `#[must_use]` attribute",
             );
@@ -67,11 +67,11 @@ pub(super) fn check_impl_item<'tcx>(cx: &LateContext<'tcx>, item: &'tcx hir::Imp
 
 pub(super) fn check_trait_item<'tcx>(cx: &LateContext<'tcx>, item: &'tcx hir::TraitItem<'_>) {
     if let hir::TraitItemKind::Fn(ref sig, ref eid) = item.kind {
-        let is_public = cx.access_levels.is_exported(item.def_id.def_id);
+        let is_public = cx.effective_visibilities.is_exported(item.owner_id.def_id);
         let fn_header_span = item.span.with_hi(sig.decl.output.span().hi());
 
         let attrs = cx.tcx.hir().attrs(item.hir_id());
-        let attr = cx.tcx.get_attr(item.def_id.to_def_id(), sym::must_use);
+        let attr = cx.tcx.get_attr(item.owner_id.to_def_id(), sym::must_use);
         if let Some(attr) = attr {
             check_needless_must_use(cx, sig.decl, item.hir_id(), item.span, fn_header_span, attr);
         } else if let hir::TraitFn::Provided(eid) = *eid {
@@ -82,7 +82,7 @@ pub(super) fn check_trait_item<'tcx>(cx: &LateContext<'tcx>, item: &'tcx hir::Tr
                     sig.decl,
                     body,
                     item.span,
-                    item.def_id.def_id,
+                    item.owner_id.def_id,
                     item.span.with_hi(sig.decl.output.span().hi()),
                     "this method could have a `#[must_use]` attribute",
                 );
@@ -137,7 +137,7 @@ fn check_must_use_candidate<'tcx>(
         || mutates_static(cx, body)
         || in_external_macro(cx.sess(), item_span)
         || returns_unit(decl)
-        || !cx.access_levels.is_exported(item_id)
+        || !cx.effective_visibilities.is_exported(item_id)
         || is_must_use_ty(cx, return_ty(cx, cx.tcx.hir().local_def_id_to_hir_id(item_id)))
     {
         return;
@@ -181,15 +181,17 @@ fn is_mutable_pat(cx: &LateContext<'_>, pat: &hir::Pat<'_>, tys: &mut DefIdSet)
     }
 }
 
-static KNOWN_WRAPPER_TYS: &[&[&str]] = &[&["alloc", "rc", "Rc"], &["std", "sync", "Arc"]];
+static KNOWN_WRAPPER_TYS: &[Symbol] = &[sym::Rc, sym::Arc];
 
 fn is_mutable_ty<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>, span: Span, tys: &mut DefIdSet) -> bool {
     match *ty.kind() {
         // primitive types are never mutable
         ty::Bool | ty::Char | ty::Int(_) | ty::Uint(_) | ty::Float(_) | ty::Str => false,
         ty::Adt(adt, substs) => {
-            tys.insert(adt.did()) && !ty.is_freeze(cx.tcx.at(span), cx.param_env)
-                || KNOWN_WRAPPER_TYS.iter().any(|path| match_def_path(cx, adt.did(), path))
+            tys.insert(adt.did()) && !ty.is_freeze(cx.tcx, cx.param_env)
+                || KNOWN_WRAPPER_TYS
+                    .iter()
+                    .any(|&sym| cx.tcx.is_diagnostic_item(sym, adt.did()))
                     && substs.types().any(|ty| is_mutable_ty(cx, ty, span, tys))
         },
         ty::Tuple(substs) => substs.iter().any(|ty| is_mutable_ty(cx, ty, span, tys)),
diff --git a/src/tools/clippy/clippy_lints/src/functions/not_unsafe_ptr_arg_deref.rs b/src/tools/clippy/clippy_lints/src/functions/not_unsafe_ptr_arg_deref.rs
index b7595d101e0f..2c0bf551fd7e 100644
--- a/src/tools/clippy/clippy_lints/src/functions/not_unsafe_ptr_arg_deref.rs
+++ b/src/tools/clippy/clippy_lints/src/functions/not_unsafe_ptr_arg_deref.rs
@@ -31,7 +31,7 @@ pub(super) fn check_fn<'tcx>(
 pub(super) fn check_trait_item<'tcx>(cx: &LateContext<'tcx>, item: &'tcx hir::TraitItem<'_>) {
     if let hir::TraitItemKind::Fn(ref sig, hir::TraitFn::Provided(eid)) = item.kind {
         let body = cx.tcx.hir().body(eid);
-        check_raw_ptr(cx, sig.header.unsafety, sig.decl, body, item.def_id.def_id);
+        check_raw_ptr(cx, sig.header.unsafety, sig.decl, body, item.owner_id.def_id);
     }
 }
 
@@ -42,7 +42,7 @@ fn check_raw_ptr<'tcx>(
     body: &'tcx hir::Body<'tcx>,
     def_id: LocalDefId,
 ) {
-    if unsafety == hir::Unsafety::Normal && cx.access_levels.is_exported(def_id) {
+    if unsafety == hir::Unsafety::Normal && cx.effective_visibilities.is_exported(def_id) {
         let raw_ptrs = iter_input_pats(decl, body)
             .filter_map(|arg| raw_ptr_arg(cx, arg))
             .collect::<HirIdSet>();
diff --git a/src/tools/clippy/clippy_lints/src/functions/result.rs b/src/tools/clippy/clippy_lints/src/functions/result.rs
index 113c4e9f5091..5c63fb2acb11 100644
--- a/src/tools/clippy/clippy_lints/src/functions/result.rs
+++ b/src/tools/clippy/clippy_lints/src/functions/result.rs
@@ -34,9 +34,9 @@ fn result_err_ty<'tcx>(
 
 pub(super) fn check_item<'tcx>(cx: &LateContext<'tcx>, item: &hir::Item<'tcx>, large_err_threshold: u64) {
     if let hir::ItemKind::Fn(ref sig, _generics, _) = item.kind
-        && let Some((hir_ty, err_ty)) = result_err_ty(cx, sig.decl, item.def_id.def_id, item.span)
+        && let Some((hir_ty, err_ty)) = result_err_ty(cx, sig.decl, item.owner_id.def_id, item.span)
     {
-        if cx.access_levels.is_exported(item.def_id.def_id) {
+        if cx.effective_visibilities.is_exported(item.owner_id.def_id) {
             let fn_header_span = item.span.with_hi(sig.decl.output.span().hi());
             check_result_unit_err(cx, err_ty, fn_header_span);
         }
@@ -47,10 +47,10 @@ pub(super) fn check_item<'tcx>(cx: &LateContext<'tcx>, item: &hir::Item<'tcx>, l
 pub(super) fn check_impl_item<'tcx>(cx: &LateContext<'tcx>, item: &hir::ImplItem<'tcx>, large_err_threshold: u64) {
     // Don't lint if method is a trait's implementation, we can't do anything about those
     if let hir::ImplItemKind::Fn(ref sig, _) = item.kind
-        && let Some((hir_ty, err_ty)) = result_err_ty(cx, sig.decl, item.def_id.def_id, item.span)
-        && trait_ref_of_method(cx, item.def_id.def_id).is_none()
+        && let Some((hir_ty, err_ty)) = result_err_ty(cx, sig.decl, item.owner_id.def_id, item.span)
+        && trait_ref_of_method(cx, item.owner_id.def_id).is_none()
     {
-        if cx.access_levels.is_exported(item.def_id.def_id) {
+        if cx.effective_visibilities.is_exported(item.owner_id.def_id) {
             let fn_header_span = item.span.with_hi(sig.decl.output.span().hi());
             check_result_unit_err(cx, err_ty, fn_header_span);
         }
@@ -61,8 +61,8 @@ pub(super) fn check_impl_item<'tcx>(cx: &LateContext<'tcx>, item: &hir::ImplItem
 pub(super) fn check_trait_item<'tcx>(cx: &LateContext<'tcx>, item: &hir::TraitItem<'tcx>, large_err_threshold: u64) {
     if let hir::TraitItemKind::Fn(ref sig, _) = item.kind {
         let fn_header_span = item.span.with_hi(sig.decl.output.span().hi());
-        if let Some((hir_ty, err_ty)) = result_err_ty(cx, sig.decl, item.def_id.def_id, item.span) {
-            if cx.access_levels.is_exported(item.def_id.def_id) {
+        if let Some((hir_ty, err_ty)) = result_err_ty(cx, sig.decl, item.owner_id.def_id, item.span) {
+            if cx.effective_visibilities.is_exported(item.owner_id.def_id) {
                 check_result_unit_err(cx, err_ty, fn_header_span);
             }
             check_result_large_err(cx, err_ty, hir_ty.span, large_err_threshold);
diff --git a/src/tools/clippy/clippy_lints/src/functions/too_many_lines.rs b/src/tools/clippy/clippy_lints/src/functions/too_many_lines.rs
index f83f8b40f94b..bd473ac7e51b 100644
--- a/src/tools/clippy/clippy_lints/src/functions/too_many_lines.rs
+++ b/src/tools/clippy/clippy_lints/src/functions/too_many_lines.rs
@@ -22,9 +22,8 @@ pub(super) fn check_fn(
         return;
     }
 
-    let code_snippet = match snippet_opt(cx, body.value.span) {
-        Some(s) => s,
-        _ => return,
+    let Some(code_snippet) = snippet_opt(cx, body.value.span) else {
+        return
     };
     let mut line_count: u64 = 0;
     let mut in_comment = false;
diff --git a/src/tools/clippy/clippy_lints/src/implicit_hasher.rs b/src/tools/clippy/clippy_lints/src/implicit_hasher.rs
index 93efe957b1dc..94e06cf704ba 100644
--- a/src/tools/clippy/clippy_lints/src/implicit_hasher.rs
+++ b/src/tools/clippy/clippy_lints/src/implicit_hasher.rs
@@ -111,7 +111,7 @@ impl<'tcx> LateLintPass<'tcx> for ImplicitHasher {
             }
         }
 
-        if !cx.access_levels.is_exported(item.def_id.def_id) {
+        if !cx.effective_visibilities.is_exported(item.owner_id.def_id) {
             return;
         }
 
diff --git a/src/tools/clippy/clippy_lints/src/implicit_saturating_sub.rs b/src/tools/clippy/clippy_lints/src/implicit_saturating_sub.rs
index 48edbf6ae576..29d59c26d92c 100644
--- a/src/tools/clippy/clippy_lints/src/implicit_saturating_sub.rs
+++ b/src/tools/clippy/clippy_lints/src/implicit_saturating_sub.rs
@@ -35,7 +35,7 @@ declare_clippy_lint! {
     /// ```
     #[clippy::version = "1.44.0"]
     pub IMPLICIT_SATURATING_SUB,
-    pedantic,
+    style,
     "Perform saturating subtraction instead of implicitly checking lower bound of data type"
 }
 
diff --git a/src/tools/clippy/clippy_lints/src/inherent_to_string.rs b/src/tools/clippy/clippy_lints/src/inherent_to_string.rs
index 676136df572b..14a37f535b46 100644
--- a/src/tools/clippy/clippy_lints/src/inherent_to_string.rs
+++ b/src/tools/clippy/clippy_lints/src/inherent_to_string.rs
@@ -108,7 +108,7 @@ impl<'tcx> LateLintPass<'tcx> for InherentToString {
             if is_type_diagnostic_item(cx, return_ty(cx, impl_item.hir_id()), sym::String);
 
             // Filters instances of to_string which are required by a trait
-            if trait_ref_of_method(cx, impl_item.def_id.def_id).is_none();
+            if trait_ref_of_method(cx, impl_item.owner_id.def_id).is_none();
 
             then {
                 show_lint(cx, impl_item);
@@ -124,7 +124,7 @@ fn show_lint(cx: &LateContext<'_>, item: &ImplItem<'_>) {
         .expect("Failed to get trait ID of `Display`!");
 
     // Get the real type of 'self'
-    let self_type = cx.tcx.fn_sig(item.def_id).input(0);
+    let self_type = cx.tcx.fn_sig(item.owner_id).input(0);
     let self_type = self_type.skip_binder().peel_refs();
 
     // Emit either a warning or an error
diff --git a/src/tools/clippy/clippy_lints/src/invalid_upcast_comparisons.rs b/src/tools/clippy/clippy_lints/src/invalid_upcast_comparisons.rs
index 36e03e50a8e4..0ef77e03de90 100644
--- a/src/tools/clippy/clippy_lints/src/invalid_upcast_comparisons.rs
+++ b/src/tools/clippy/clippy_lints/src/invalid_upcast_comparisons.rs
@@ -145,9 +145,7 @@ impl<'tcx> LateLintPass<'tcx> for InvalidUpcastComparisons {
     fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
         if let ExprKind::Binary(ref cmp, lhs, rhs) = expr.kind {
             let normalized = comparisons::normalize_comparison(cmp.node, lhs, rhs);
-            let (rel, normalized_lhs, normalized_rhs) = if let Some(val) = normalized {
-                val
-            } else {
+            let Some((rel, normalized_lhs, normalized_rhs)) = normalized else {
                 return;
             };
 
diff --git a/src/tools/clippy/clippy_lints/src/iter_not_returning_iterator.rs b/src/tools/clippy/clippy_lints/src/iter_not_returning_iterator.rs
index ea9f046fb973..e76de77f195d 100644
--- a/src/tools/clippy/clippy_lints/src/iter_not_returning_iterator.rs
+++ b/src/tools/clippy/clippy_lints/src/iter_not_returning_iterator.rs
@@ -44,7 +44,7 @@ impl<'tcx> LateLintPass<'tcx> for IterNotReturningIterator {
         let name = item.ident.name.as_str();
         if matches!(name, "iter" | "iter_mut") {
             if let TraitItemKind::Fn(fn_sig, _) = &item.kind {
-                check_sig(cx, name, fn_sig, item.def_id.def_id);
+                check_sig(cx, name, fn_sig, item.owner_id.def_id);
             }
         }
     }
@@ -58,7 +58,7 @@ impl<'tcx> LateLintPass<'tcx> for IterNotReturningIterator {
             )
         {
             if let ImplItemKind::Fn(fn_sig, _) = &item.kind {
-                check_sig(cx, name, fn_sig, item.def_id.def_id);
+                check_sig(cx, name, fn_sig, item.owner_id.def_id);
             }
         }
     }
diff --git a/src/tools/clippy/clippy_lints/src/large_enum_variant.rs b/src/tools/clippy/clippy_lints/src/large_enum_variant.rs
index eb13d0869c03..06e957285499 100644
--- a/src/tools/clippy/clippy_lints/src/large_enum_variant.rs
+++ b/src/tools/clippy/clippy_lints/src/large_enum_variant.rs
@@ -123,10 +123,9 @@ impl<'tcx> LateLintPass<'tcx> for LargeEnumVariant {
             return;
         }
         if let ItemKind::Enum(ref def, _) = item.kind {
-            let ty = cx.tcx.type_of(item.def_id);
-            let (adt, subst) = match ty.kind() {
-                Adt(adt, subst) => (adt, subst),
-                _ => panic!("already checked whether this is an enum"),
+            let ty = cx.tcx.type_of(item.owner_id);
+            let Adt(adt, subst) = ty.kind() else {
+                panic!("already checked whether this is an enum")
             };
             if adt.variants().len() <= 1 {
                 return;
diff --git a/src/tools/clippy/clippy_lints/src/len_zero.rs b/src/tools/clippy/clippy_lints/src/len_zero.rs
index 3a563736fb07..b0cba40c27a5 100644
--- a/src/tools/clippy/clippy_lints/src/len_zero.rs
+++ b/src/tools/clippy/clippy_lints/src/len_zero.rs
@@ -134,7 +134,7 @@ impl<'tcx> LateLintPass<'tcx> for LenZero {
             if item.ident.name == sym::len;
             if let ImplItemKind::Fn(sig, _) = &item.kind;
             if sig.decl.implicit_self.has_implicit_self();
-            if cx.access_levels.is_exported(item.def_id.def_id);
+            if cx.effective_visibilities.is_exported(item.owner_id.def_id);
             if matches!(sig.decl.output, FnRetTy::Return(_));
             if let Some(imp) = get_parent_as_impl(cx.tcx, item.hir_id());
             if imp.of_trait.is_none();
@@ -143,7 +143,7 @@ impl<'tcx> LateLintPass<'tcx> for LenZero {
             if let Some(local_id) = ty_id.as_local();
             let ty_hir_id = cx.tcx.hir().local_def_id_to_hir_id(local_id);
             if !is_lint_allowed(cx, LEN_WITHOUT_IS_EMPTY, ty_hir_id);
-            if let Some(output) = parse_len_output(cx, cx.tcx.fn_sig(item.def_id).skip_binder());
+            if let Some(output) = parse_len_output(cx, cx.tcx.fn_sig(item.owner_id).skip_binder());
             then {
                 let (name, kind) = match cx.tcx.hir().find(ty_hir_id) {
                     Some(Node::ForeignItem(x)) => (x.ident.name, "extern type"),
@@ -195,7 +195,7 @@ fn check_trait_items(cx: &LateContext<'_>, visited_trait: &Item<'_>, trait_items
     fn is_named_self(cx: &LateContext<'_>, item: &TraitItemRef, name: Symbol) -> bool {
         item.ident.name == name
             && if let AssocItemKind::Fn { has_self } = item.kind {
-                has_self && { cx.tcx.fn_sig(item.id.def_id).inputs().skip_binder().len() == 1 }
+                has_self && { cx.tcx.fn_sig(item.id.owner_id).inputs().skip_binder().len() == 1 }
             } else {
                 false
             }
@@ -210,11 +210,11 @@ fn check_trait_items(cx: &LateContext<'_>, visited_trait: &Item<'_>, trait_items
         }
     }
 
-    if cx.access_levels.is_exported(visited_trait.def_id.def_id)
+    if cx.effective_visibilities.is_exported(visited_trait.owner_id.def_id)
         && trait_items.iter().any(|i| is_named_self(cx, i, sym::len))
     {
         let mut current_and_super_traits = DefIdSet::default();
-        fill_trait_set(visited_trait.def_id.to_def_id(), &mut current_and_super_traits, cx);
+        fill_trait_set(visited_trait.owner_id.to_def_id(), &mut current_and_super_traits, cx);
         let is_empty = sym!(is_empty);
 
         let is_empty_method_found = current_and_super_traits
@@ -331,7 +331,7 @@ fn check_for_is_empty<'tcx>(
             None,
             None,
         ),
-        Some(is_empty) if !cx.access_levels.is_exported(is_empty.def_id.expect_local()) => (
+        Some(is_empty) if !cx.effective_visibilities.is_exported(is_empty.def_id.expect_local()) => (
             format!(
                 "{item_kind} `{}` has a public `len` method, but a private `is_empty` method",
                 item_name.as_str(),
diff --git a/src/tools/clippy/clippy_lints/src/let_if_seq.rs b/src/tools/clippy/clippy_lints/src/let_if_seq.rs
index 13071d64441a..db41bc67da1a 100644
--- a/src/tools/clippy/clippy_lints/src/let_if_seq.rs
+++ b/src/tools/clippy/clippy_lints/src/let_if_seq.rs
@@ -74,7 +74,7 @@ impl<'tcx> LateLintPass<'tcx> for LetIfSeq {
                     let span = stmt.span.to(if_.span);
 
                     let has_interior_mutability = !cx.typeck_results().node_type(canonical_id).is_freeze(
-                        cx.tcx.at(span),
+                        cx.tcx,
                         cx.param_env,
                     );
                     if has_interior_mutability { return; }
diff --git a/src/tools/clippy/clippy_lints/src/let_underscore.rs b/src/tools/clippy/clippy_lints/src/let_underscore.rs
index 176787497ebf..b7798b1c1d74 100644
--- a/src/tools/clippy/clippy_lints/src/let_underscore.rs
+++ b/src/tools/clippy/clippy_lints/src/let_underscore.rs
@@ -1,5 +1,5 @@
 use clippy_utils::diagnostics::span_lint_and_help;
-use clippy_utils::ty::{is_must_use_ty, match_type};
+use clippy_utils::ty::{is_must_use_ty, is_type_diagnostic_item, match_type};
 use clippy_utils::{is_must_use_func_call, paths};
 use if_chain::if_chain;
 use rustc_hir::{Local, PatKind};
@@ -7,6 +7,7 @@ use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::lint::in_external_macro;
 use rustc_middle::ty::subst::GenericArgKind;
 use rustc_session::{declare_lint_pass, declare_tool_lint};
+use rustc_span::{sym, Symbol};
 
 declare_clippy_lint! {
     /// ### What it does
@@ -99,10 +100,9 @@ declare_clippy_lint! {
 
 declare_lint_pass!(LetUnderscore => [LET_UNDERSCORE_MUST_USE, LET_UNDERSCORE_LOCK, LET_UNDERSCORE_DROP]);
 
-const SYNC_GUARD_PATHS: [&[&str]; 6] = [
-    &paths::MUTEX_GUARD,
-    &paths::RWLOCK_READ_GUARD,
-    &paths::RWLOCK_WRITE_GUARD,
+const SYNC_GUARD_SYMS: [Symbol; 3] = [sym::MutexGuard, sym::RwLockReadGuard, sym::RwLockWriteGuard];
+
+const SYNC_GUARD_PATHS: [&[&str]; 3] = [
     &paths::PARKING_LOT_MUTEX_GUARD,
     &paths::PARKING_LOT_RWLOCK_READ_GUARD,
     &paths::PARKING_LOT_RWLOCK_WRITE_GUARD,
@@ -121,7 +121,10 @@ impl<'tcx> LateLintPass<'tcx> for LetUnderscore {
                 let init_ty = cx.typeck_results().expr_ty(init);
                 let contains_sync_guard = init_ty.walk().any(|inner| match inner.unpack() {
                     GenericArgKind::Type(inner_ty) => {
-                        SYNC_GUARD_PATHS.iter().any(|path| match_type(cx, inner_ty, path))
+                        SYNC_GUARD_SYMS
+                            .iter()
+                            .any(|&sym| is_type_diagnostic_item(cx, inner_ty, sym))
+                            || SYNC_GUARD_PATHS.iter().any(|path| match_type(cx, inner_ty, path))
                     },
 
                     GenericArgKind::Lifetime(_) | GenericArgKind::Const(_) => false,
@@ -134,7 +137,7 @@ impl<'tcx> LateLintPass<'tcx> for LetUnderscore {
                         "non-binding let on a synchronization lock",
                         None,
                         "consider using an underscore-prefixed named \
-                            binding or dropping explicitly with `std::mem::drop`"
+                            binding or dropping explicitly with `std::mem::drop`",
                     );
                 } else if init_ty.needs_drop(cx.tcx, cx.param_env) {
                     span_lint_and_help(
@@ -144,7 +147,7 @@ impl<'tcx> LateLintPass<'tcx> for LetUnderscore {
                         "non-binding `let` on a type that implements `Drop`",
                         None,
                         "consider using an underscore-prefixed named \
-                            binding or dropping explicitly with `std::mem::drop`"
+                            binding or dropping explicitly with `std::mem::drop`",
                     );
                 } else if is_must_use_ty(cx, cx.typeck_results().expr_ty(init)) {
                     span_lint_and_help(
@@ -153,7 +156,7 @@ impl<'tcx> LateLintPass<'tcx> for LetUnderscore {
                         local.span,
                         "non-binding let on an expression with `#[must_use]` type",
                         None,
-                        "consider explicitly using expression value"
+                        "consider explicitly using expression value",
                     );
                 } else if is_must_use_func_call(cx, init) {
                     span_lint_and_help(
@@ -162,7 +165,7 @@ impl<'tcx> LateLintPass<'tcx> for LetUnderscore {
                         local.span,
                         "non-binding let on a result of a `#[must_use]` function",
                         None,
-                        "consider explicitly using function result"
+                        "consider explicitly using function result",
                     );
                 }
             }
diff --git a/src/tools/clippy/clippy_lints/src/lib.register_all.rs b/src/tools/clippy/clippy_lints/src/lib.register_all.rs
index fe1f0b56646c..c455e1561b71 100644
--- a/src/tools/clippy/clippy_lints/src/lib.register_all.rs
+++ b/src/tools/clippy/clippy_lints/src/lib.register_all.rs
@@ -25,6 +25,7 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(casts::CAST_ABS_TO_UNSIGNED),
     LintId::of(casts::CAST_ENUM_CONSTRUCTOR),
     LintId::of(casts::CAST_ENUM_TRUNCATION),
+    LintId::of(casts::CAST_NAN_TO_INT),
     LintId::of(casts::CAST_REF_TO_MUT),
     LintId::of(casts::CAST_SLICE_DIFFERENT_SIZES),
     LintId::of(casts::CAST_SLICE_FROM_RAW_PARTS),
@@ -71,6 +72,7 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(format::USELESS_FORMAT),
     LintId::of(format_args::FORMAT_IN_FORMAT_ARGS),
     LintId::of(format_args::TO_STRING_IN_FORMAT_ARGS),
+    LintId::of(format_args::UNUSED_FORMAT_SPECS),
     LintId::of(format_impl::PRINT_IN_FORMAT_IMPL),
     LintId::of(format_impl::RECURSIVE_FORMAT_IMPL),
     LintId::of(formatting::POSSIBLE_MISSING_COMMA),
@@ -87,6 +89,7 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(functions::TOO_MANY_ARGUMENTS),
     LintId::of(if_let_mutex::IF_LET_MUTEX),
     LintId::of(implicit_saturating_add::IMPLICIT_SATURATING_ADD),
+    LintId::of(implicit_saturating_sub::IMPLICIT_SATURATING_SUB),
     LintId::of(indexing_slicing::OUT_OF_BOUNDS_INDEXING),
     LintId::of(infinite_iter::INFINITE_ITER),
     LintId::of(inherent_to_string::INHERENT_TO_STRING),
@@ -136,6 +139,7 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(match_result_ok::MATCH_RESULT_OK),
     LintId::of(matches::COLLAPSIBLE_MATCH),
     LintId::of(matches::INFALLIBLE_DESTRUCTURING_MATCH),
+    LintId::of(matches::MANUAL_FILTER),
     LintId::of(matches::MANUAL_MAP),
     LintId::of(matches::MANUAL_UNWRAP_OR),
     LintId::of(matches::MATCH_AS_REF),
diff --git a/src/tools/clippy/clippy_lints/src/lib.register_complexity.rs b/src/tools/clippy/clippy_lints/src/lib.register_complexity.rs
index a58d066fa6b6..8be9dc4baf19 100644
--- a/src/tools/clippy/clippy_lints/src/lib.register_complexity.rs
+++ b/src/tools/clippy/clippy_lints/src/lib.register_complexity.rs
@@ -13,6 +13,7 @@ store.register_group(true, "clippy::complexity", Some("clippy_complexity"), vec!
     LintId::of(double_parens::DOUBLE_PARENS),
     LintId::of(explicit_write::EXPLICIT_WRITE),
     LintId::of(format::USELESS_FORMAT),
+    LintId::of(format_args::UNUSED_FORMAT_SPECS),
     LintId::of(functions::TOO_MANY_ARGUMENTS),
     LintId::of(int_plus_one::INT_PLUS_ONE),
     LintId::of(lifetimes::EXTRA_UNUSED_LIFETIMES),
@@ -27,6 +28,7 @@ store.register_group(true, "clippy::complexity", Some("clippy_complexity"), vec!
     LintId::of(manual_strip::MANUAL_STRIP),
     LintId::of(map_unit_fn::OPTION_MAP_UNIT_FN),
     LintId::of(map_unit_fn::RESULT_MAP_UNIT_FN),
+    LintId::of(matches::MANUAL_FILTER),
     LintId::of(matches::MANUAL_UNWRAP_OR),
     LintId::of(matches::MATCH_AS_REF),
     LintId::of(matches::MATCH_SINGLE_BINDING),
diff --git a/src/tools/clippy/clippy_lints/src/lib.register_internal.rs b/src/tools/clippy/clippy_lints/src/lib.register_internal.rs
index 71dfdab369b9..40c94c6e8d33 100644
--- a/src/tools/clippy/clippy_lints/src/lib.register_internal.rs
+++ b/src/tools/clippy/clippy_lints/src/lib.register_internal.rs
@@ -3,20 +3,20 @@
 // Manual edits will be overwritten.
 
 store.register_group(true, "clippy::internal", Some("clippy_internal"), vec![
-    LintId::of(utils::internal_lints::CLIPPY_LINTS_INTERNAL),
-    LintId::of(utils::internal_lints::COLLAPSIBLE_SPAN_LINT_CALLS),
-    LintId::of(utils::internal_lints::COMPILER_LINT_FUNCTIONS),
-    LintId::of(utils::internal_lints::DEFAULT_DEPRECATION_REASON),
-    LintId::of(utils::internal_lints::DEFAULT_LINT),
-    LintId::of(utils::internal_lints::IF_CHAIN_STYLE),
-    LintId::of(utils::internal_lints::INTERNING_DEFINED_SYMBOL),
-    LintId::of(utils::internal_lints::INVALID_CLIPPY_VERSION_ATTRIBUTE),
-    LintId::of(utils::internal_lints::INVALID_PATHS),
-    LintId::of(utils::internal_lints::LINT_WITHOUT_LINT_PASS),
-    LintId::of(utils::internal_lints::MISSING_CLIPPY_VERSION_ATTRIBUTE),
-    LintId::of(utils::internal_lints::MISSING_MSRV_ATTR_IMPL),
-    LintId::of(utils::internal_lints::OUTER_EXPN_EXPN_DATA),
-    LintId::of(utils::internal_lints::PRODUCE_ICE),
-    LintId::of(utils::internal_lints::UNNECESSARY_DEF_PATH),
-    LintId::of(utils::internal_lints::UNNECESSARY_SYMBOL_STR),
+    LintId::of(utils::internal_lints::clippy_lints_internal::CLIPPY_LINTS_INTERNAL),
+    LintId::of(utils::internal_lints::collapsible_calls::COLLAPSIBLE_SPAN_LINT_CALLS),
+    LintId::of(utils::internal_lints::compiler_lint_functions::COMPILER_LINT_FUNCTIONS),
+    LintId::of(utils::internal_lints::if_chain_style::IF_CHAIN_STYLE),
+    LintId::of(utils::internal_lints::interning_defined_symbol::INTERNING_DEFINED_SYMBOL),
+    LintId::of(utils::internal_lints::interning_defined_symbol::UNNECESSARY_SYMBOL_STR),
+    LintId::of(utils::internal_lints::invalid_paths::INVALID_PATHS),
+    LintId::of(utils::internal_lints::lint_without_lint_pass::DEFAULT_DEPRECATION_REASON),
+    LintId::of(utils::internal_lints::lint_without_lint_pass::DEFAULT_LINT),
+    LintId::of(utils::internal_lints::lint_without_lint_pass::INVALID_CLIPPY_VERSION_ATTRIBUTE),
+    LintId::of(utils::internal_lints::lint_without_lint_pass::LINT_WITHOUT_LINT_PASS),
+    LintId::of(utils::internal_lints::lint_without_lint_pass::MISSING_CLIPPY_VERSION_ATTRIBUTE),
+    LintId::of(utils::internal_lints::msrv_attr_impl::MISSING_MSRV_ATTR_IMPL),
+    LintId::of(utils::internal_lints::outer_expn_data_pass::OUTER_EXPN_EXPN_DATA),
+    LintId::of(utils::internal_lints::produce_ice::PRODUCE_ICE),
+    LintId::of(utils::internal_lints::unnecessary_def_path::UNNECESSARY_DEF_PATH),
 ])
diff --git a/src/tools/clippy/clippy_lints/src/lib.register_lints.rs b/src/tools/clippy/clippy_lints/src/lib.register_lints.rs
index 306cb6a61c94..800e3a876713 100644
--- a/src/tools/clippy/clippy_lints/src/lib.register_lints.rs
+++ b/src/tools/clippy/clippy_lints/src/lib.register_lints.rs
@@ -4,37 +4,37 @@
 
 store.register_lints(&[
     #[cfg(feature = "internal")]
-    utils::internal_lints::CLIPPY_LINTS_INTERNAL,
+    utils::internal_lints::clippy_lints_internal::CLIPPY_LINTS_INTERNAL,
     #[cfg(feature = "internal")]
-    utils::internal_lints::COLLAPSIBLE_SPAN_LINT_CALLS,
+    utils::internal_lints::collapsible_calls::COLLAPSIBLE_SPAN_LINT_CALLS,
     #[cfg(feature = "internal")]
-    utils::internal_lints::COMPILER_LINT_FUNCTIONS,
+    utils::internal_lints::compiler_lint_functions::COMPILER_LINT_FUNCTIONS,
     #[cfg(feature = "internal")]
-    utils::internal_lints::DEFAULT_DEPRECATION_REASON,
+    utils::internal_lints::if_chain_style::IF_CHAIN_STYLE,
     #[cfg(feature = "internal")]
-    utils::internal_lints::DEFAULT_LINT,
+    utils::internal_lints::interning_defined_symbol::INTERNING_DEFINED_SYMBOL,
     #[cfg(feature = "internal")]
-    utils::internal_lints::IF_CHAIN_STYLE,
+    utils::internal_lints::interning_defined_symbol::UNNECESSARY_SYMBOL_STR,
     #[cfg(feature = "internal")]
-    utils::internal_lints::INTERNING_DEFINED_SYMBOL,
+    utils::internal_lints::invalid_paths::INVALID_PATHS,
     #[cfg(feature = "internal")]
-    utils::internal_lints::INVALID_CLIPPY_VERSION_ATTRIBUTE,
+    utils::internal_lints::lint_without_lint_pass::DEFAULT_DEPRECATION_REASON,
     #[cfg(feature = "internal")]
-    utils::internal_lints::INVALID_PATHS,
+    utils::internal_lints::lint_without_lint_pass::DEFAULT_LINT,
     #[cfg(feature = "internal")]
-    utils::internal_lints::LINT_WITHOUT_LINT_PASS,
+    utils::internal_lints::lint_without_lint_pass::INVALID_CLIPPY_VERSION_ATTRIBUTE,
     #[cfg(feature = "internal")]
-    utils::internal_lints::MISSING_CLIPPY_VERSION_ATTRIBUTE,
+    utils::internal_lints::lint_without_lint_pass::LINT_WITHOUT_LINT_PASS,
     #[cfg(feature = "internal")]
-    utils::internal_lints::MISSING_MSRV_ATTR_IMPL,
+    utils::internal_lints::lint_without_lint_pass::MISSING_CLIPPY_VERSION_ATTRIBUTE,
     #[cfg(feature = "internal")]
-    utils::internal_lints::OUTER_EXPN_EXPN_DATA,
+    utils::internal_lints::msrv_attr_impl::MISSING_MSRV_ATTR_IMPL,
     #[cfg(feature = "internal")]
-    utils::internal_lints::PRODUCE_ICE,
+    utils::internal_lints::outer_expn_data_pass::OUTER_EXPN_EXPN_DATA,
     #[cfg(feature = "internal")]
-    utils::internal_lints::UNNECESSARY_DEF_PATH,
+    utils::internal_lints::produce_ice::PRODUCE_ICE,
     #[cfg(feature = "internal")]
-    utils::internal_lints::UNNECESSARY_SYMBOL_STR,
+    utils::internal_lints::unnecessary_def_path::UNNECESSARY_DEF_PATH,
     almost_complete_letter_range::ALMOST_COMPLETE_LETTER_RANGE,
     approx_const::APPROX_CONSTANT,
     as_conversions::AS_CONVERSIONS,
@@ -66,12 +66,14 @@ store.register_lints(&[
     cargo::NEGATIVE_FEATURE_NAMES,
     cargo::REDUNDANT_FEATURE_NAMES,
     cargo::WILDCARD_DEPENDENCIES,
+    casts::AS_PTR_CAST_MUT,
     casts::AS_UNDERSCORE,
     casts::BORROW_AS_PTR,
     casts::CAST_ABS_TO_UNSIGNED,
     casts::CAST_ENUM_CONSTRUCTOR,
     casts::CAST_ENUM_TRUNCATION,
     casts::CAST_LOSSLESS,
+    casts::CAST_NAN_TO_INT,
     casts::CAST_POSSIBLE_TRUNCATION,
     casts::CAST_POSSIBLE_WRAP,
     casts::CAST_PRECISION_LOSS,
@@ -162,6 +164,7 @@ store.register_lints(&[
     format_args::FORMAT_IN_FORMAT_ARGS,
     format_args::TO_STRING_IN_FORMAT_ARGS,
     format_args::UNINLINED_FORMAT_ARGS,
+    format_args::UNUSED_FORMAT_SPECS,
     format_impl::PRINT_IN_FORMAT_IMPL,
     format_impl::RECURSIVE_FORMAT_IMPL,
     format_push_string::FORMAT_PUSH_STRING,
@@ -258,6 +261,7 @@ store.register_lints(&[
     match_result_ok::MATCH_RESULT_OK,
     matches::COLLAPSIBLE_MATCH,
     matches::INFALLIBLE_DESTRUCTURING_MATCH,
+    matches::MANUAL_FILTER,
     matches::MANUAL_MAP,
     matches::MANUAL_UNWRAP_OR,
     matches::MATCH_AS_REF,
@@ -403,6 +407,7 @@ store.register_lints(&[
     missing_doc::MISSING_DOCS_IN_PRIVATE_ITEMS,
     missing_enforced_import_rename::MISSING_ENFORCED_IMPORT_RENAMES,
     missing_inline::MISSING_INLINE_IN_PUBLIC_ITEMS,
+    missing_trait_methods::MISSING_TRAIT_METHODS,
     mixed_read_write_in_expression::DIVERGING_SUB_EXPRESSION,
     mixed_read_write_in_expression::MIXED_READ_WRITE_IN_EXPRESSION,
     module_style::MOD_MODULE_FILES,
@@ -475,6 +480,7 @@ store.register_lints(&[
     panic_unimplemented::TODO,
     panic_unimplemented::UNIMPLEMENTED,
     panic_unimplemented::UNREACHABLE,
+    partial_pub_fields::PARTIAL_PUB_FIELDS,
     partialeq_ne_impl::PARTIALEQ_NE_IMPL,
     partialeq_to_none::PARTIALEQ_TO_NONE,
     pass_by_ref_or_value::LARGE_TYPES_PASSED_BY_VALUE,
diff --git a/src/tools/clippy/clippy_lints/src/lib.register_nursery.rs b/src/tools/clippy/clippy_lints/src/lib.register_nursery.rs
index e0b4639af53e..65616d28d8f1 100644
--- a/src/tools/clippy/clippy_lints/src/lib.register_nursery.rs
+++ b/src/tools/clippy/clippy_lints/src/lib.register_nursery.rs
@@ -4,6 +4,7 @@
 
 store.register_group(true, "clippy::nursery", Some("clippy_nursery"), vec![
     LintId::of(attrs::EMPTY_LINE_AFTER_OUTER_ATTR),
+    LintId::of(casts::AS_PTR_CAST_MUT),
     LintId::of(cognitive_complexity::COGNITIVE_COMPLEXITY),
     LintId::of(copies::BRANCHES_SHARING_CODE),
     LintId::of(derive::DERIVE_PARTIAL_EQ_WITHOUT_EQ),
diff --git a/src/tools/clippy/clippy_lints/src/lib.register_pedantic.rs b/src/tools/clippy/clippy_lints/src/lib.register_pedantic.rs
index bc2f0beb358a..44e969585b50 100644
--- a/src/tools/clippy/clippy_lints/src/lib.register_pedantic.rs
+++ b/src/tools/clippy/clippy_lints/src/lib.register_pedantic.rs
@@ -34,7 +34,6 @@ store.register_group(true, "clippy::pedantic", Some("clippy_pedantic"), vec![
     LintId::of(functions::TOO_MANY_LINES),
     LintId::of(if_not_else::IF_NOT_ELSE),
     LintId::of(implicit_hasher::IMPLICIT_HASHER),
-    LintId::of(implicit_saturating_sub::IMPLICIT_SATURATING_SUB),
     LintId::of(inconsistent_struct_constructor::INCONSISTENT_STRUCT_CONSTRUCTOR),
     LintId::of(infinite_iter::MAYBE_INFINITE_ITER),
     LintId::of(invalid_upcast_comparisons::INVALID_UPCAST_COMPARISONS),
diff --git a/src/tools/clippy/clippy_lints/src/lib.register_restriction.rs b/src/tools/clippy/clippy_lints/src/lib.register_restriction.rs
index 6eb9b3d3b9b7..f62d57af5b47 100644
--- a/src/tools/clippy/clippy_lints/src/lib.register_restriction.rs
+++ b/src/tools/clippy/clippy_lints/src/lib.register_restriction.rs
@@ -47,6 +47,7 @@ store.register_group(true, "clippy::restriction", Some("clippy_restriction"), ve
     LintId::of(missing_doc::MISSING_DOCS_IN_PRIVATE_ITEMS),
     LintId::of(missing_enforced_import_rename::MISSING_ENFORCED_IMPORT_RENAMES),
     LintId::of(missing_inline::MISSING_INLINE_IN_PUBLIC_ITEMS),
+    LintId::of(missing_trait_methods::MISSING_TRAIT_METHODS),
     LintId::of(mixed_read_write_in_expression::MIXED_READ_WRITE_IN_EXPRESSION),
     LintId::of(module_style::MOD_MODULE_FILES),
     LintId::of(module_style::SELF_NAMED_MODULE_FILES),
@@ -61,6 +62,7 @@ store.register_group(true, "clippy::restriction", Some("clippy_restriction"), ve
     LintId::of(panic_unimplemented::TODO),
     LintId::of(panic_unimplemented::UNIMPLEMENTED),
     LintId::of(panic_unimplemented::UNREACHABLE),
+    LintId::of(partial_pub_fields::PARTIAL_PUB_FIELDS),
     LintId::of(pattern_type_mismatch::PATTERN_TYPE_MISMATCH),
     LintId::of(pub_use::PUB_USE),
     LintId::of(redundant_slicing::DEREF_BY_SLICING),
diff --git a/src/tools/clippy/clippy_lints/src/lib.register_style.rs b/src/tools/clippy/clippy_lints/src/lib.register_style.rs
index 8e1390167dc8..3312f5648552 100644
--- a/src/tools/clippy/clippy_lints/src/lib.register_style.rs
+++ b/src/tools/clippy/clippy_lints/src/lib.register_style.rs
@@ -31,6 +31,7 @@ store.register_group(true, "clippy::style", Some("clippy_style"), vec![
     LintId::of(functions::MUST_USE_UNIT),
     LintId::of(functions::RESULT_UNIT_ERR),
     LintId::of(implicit_saturating_add::IMPLICIT_SATURATING_ADD),
+    LintId::of(implicit_saturating_sub::IMPLICIT_SATURATING_SUB),
     LintId::of(inherent_to_string::INHERENT_TO_STRING),
     LintId::of(init_numbered_fields::INIT_NUMBERED_FIELDS),
     LintId::of(len_zero::COMPARISON_TO_EMPTY),
diff --git a/src/tools/clippy/clippy_lints/src/lib.register_suspicious.rs b/src/tools/clippy/clippy_lints/src/lib.register_suspicious.rs
index d6d95c95c85d..b70c4bb73e57 100644
--- a/src/tools/clippy/clippy_lints/src/lib.register_suspicious.rs
+++ b/src/tools/clippy/clippy_lints/src/lib.register_suspicious.rs
@@ -11,6 +11,7 @@ store.register_group(true, "clippy::suspicious", Some("clippy_suspicious"), vec!
     LintId::of(casts::CAST_ABS_TO_UNSIGNED),
     LintId::of(casts::CAST_ENUM_CONSTRUCTOR),
     LintId::of(casts::CAST_ENUM_TRUNCATION),
+    LintId::of(casts::CAST_NAN_TO_INT),
     LintId::of(casts::CAST_SLICE_FROM_RAW_PARTS),
     LintId::of(crate_in_macro_def::CRATE_IN_MACRO_DEF),
     LintId::of(drop_forget_ref::DROP_NON_DROP),
diff --git a/src/tools/clippy/clippy_lints/src/lib.rs b/src/tools/clippy/clippy_lints/src/lib.rs
index 89ffca8128a9..1307096b28d7 100644
--- a/src/tools/clippy/clippy_lints/src/lib.rs
+++ b/src/tools/clippy/clippy_lints/src/lib.rs
@@ -39,7 +39,6 @@ extern crate rustc_infer;
 extern crate rustc_lexer;
 extern crate rustc_lint;
 extern crate rustc_middle;
-extern crate rustc_mir_dataflow;
 extern crate rustc_parse;
 extern crate rustc_session;
 extern crate rustc_span;
@@ -291,6 +290,7 @@ mod missing_const_for_fn;
 mod missing_doc;
 mod missing_enforced_import_rename;
 mod missing_inline;
+mod missing_trait_methods;
 mod mixed_read_write_in_expression;
 mod module_style;
 mod multi_assignments;
@@ -326,6 +326,7 @@ mod option_if_let_else;
 mod overflow_check_conditional;
 mod panic_in_result_fn;
 mod panic_unimplemented;
+mod partial_pub_fields;
 mod partialeq_ne_impl;
 mod partialeq_to_none;
 mod pass_by_ref_or_value;
@@ -419,7 +420,7 @@ pub fn register_pre_expansion_lints(store: &mut rustc_lint::LintStore, sess: &Se
 
     let msrv = conf.msrv.as_ref().and_then(|s| {
         parse_msrv(s, None, None).or_else(|| {
-            sess.err(&format!(
+            sess.err(format!(
                 "error reading Clippy's configuration file. `{s}` is not a valid Rust version"
             ));
             None
@@ -435,7 +436,7 @@ fn read_msrv(conf: &Conf, sess: &Session) -> Option<RustcVersion> {
         .and_then(|v| parse_msrv(&v, None, None));
     let clippy_msrv = conf.msrv.as_ref().and_then(|s| {
         parse_msrv(s, None, None).or_else(|| {
-            sess.err(&format!(
+            sess.err(format!(
                 "error reading Clippy's configuration file. `{s}` is not a valid Rust version"
             ));
             None
@@ -446,7 +447,7 @@ fn read_msrv(conf: &Conf, sess: &Session) -> Option<RustcVersion> {
         if let Some(clippy_msrv) = clippy_msrv {
             // if both files have an msrv, let's compare them and emit a warning if they differ
             if clippy_msrv != cargo_msrv {
-                sess.warn(&format!(
+                sess.warn(format!(
                     "the MSRV in `clippy.toml` and `Cargo.toml` differ; using `{clippy_msrv}` from `clippy.toml`"
                 ));
             }
@@ -475,7 +476,7 @@ pub fn read_conf(sess: &Session) -> Conf {
     let TryConf { conf, errors, warnings } = utils::conf::read(&file_name);
     // all conf errors are non-fatal, we just use the default conf in case of error
     for error in errors {
-        sess.err(&format!(
+        sess.err(format!(
             "error reading Clippy's configuration file `{}`: {}",
             file_name.display(),
             format_error(error)
@@ -483,7 +484,7 @@ pub fn read_conf(sess: &Session) -> Conf {
     }
 
     for warning in warnings {
-        sess.struct_warn(&format!(
+        sess.struct_warn(format!(
             "error reading Clippy's configuration file `{}`: {}",
             file_name.display(),
             format_error(warning)
@@ -530,17 +531,23 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     // all the internal lints
     #[cfg(feature = "internal")]
     {
-        store.register_early_pass(|| Box::new(utils::internal_lints::ClippyLintsInternal));
-        store.register_early_pass(|| Box::new(utils::internal_lints::ProduceIce));
-        store.register_late_pass(|_| Box::new(utils::internal_lints::CollapsibleCalls));
-        store.register_late_pass(|_| Box::new(utils::internal_lints::CompilerLintFunctions::new()));
-        store.register_late_pass(|_| Box::new(utils::internal_lints::IfChainStyle));
-        store.register_late_pass(|_| Box::new(utils::internal_lints::InvalidPaths));
-        store.register_late_pass(|_| Box::<utils::internal_lints::InterningDefinedSymbol>::default());
-        store.register_late_pass(|_| Box::<utils::internal_lints::LintWithoutLintPass>::default());
-        store.register_late_pass(|_| Box::new(utils::internal_lints::UnnecessaryDefPath));
-        store.register_late_pass(|_| Box::new(utils::internal_lints::OuterExpnDataPass));
-        store.register_late_pass(|_| Box::new(utils::internal_lints::MsrvAttrImpl));
+        store.register_early_pass(|| Box::new(utils::internal_lints::clippy_lints_internal::ClippyLintsInternal));
+        store.register_early_pass(|| Box::new(utils::internal_lints::produce_ice::ProduceIce));
+        store.register_late_pass(|_| Box::new(utils::internal_lints::collapsible_calls::CollapsibleCalls));
+        store.register_late_pass(|_| {
+            Box::new(utils::internal_lints::compiler_lint_functions::CompilerLintFunctions::new())
+        });
+        store.register_late_pass(|_| Box::new(utils::internal_lints::if_chain_style::IfChainStyle));
+        store.register_late_pass(|_| Box::new(utils::internal_lints::invalid_paths::InvalidPaths));
+        store.register_late_pass(|_| {
+            Box::<utils::internal_lints::interning_defined_symbol::InterningDefinedSymbol>::default()
+        });
+        store.register_late_pass(|_| {
+            Box::<utils::internal_lints::lint_without_lint_pass::LintWithoutLintPass>::default()
+        });
+        store.register_late_pass(|_| Box::<utils::internal_lints::unnecessary_def_path::UnnecessaryDefPath>::default());
+        store.register_late_pass(|_| Box::new(utils::internal_lints::outer_expn_data_pass::OuterExpnDataPass));
+        store.register_late_pass(|_| Box::new(utils::internal_lints::msrv_attr_impl::MsrvAttrImpl));
     }
 
     let arithmetic_side_effects_allowed = conf.arithmetic_side_effects_allowed.clone();
@@ -910,6 +917,8 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_late_pass(|_| Box::new(bool_to_int_with_if::BoolToIntWithIf));
     store.register_late_pass(|_| Box::new(box_default::BoxDefault));
     store.register_late_pass(|_| Box::new(implicit_saturating_add::ImplicitSaturatingAdd));
+    store.register_early_pass(|| Box::new(partial_pub_fields::PartialPubFields));
+    store.register_late_pass(|_| Box::new(missing_trait_methods::MissingTraitMethods));
     // add lints here, do not remove this comment, it's used in `new_lint`
 }
 
diff --git a/src/tools/clippy/clippy_lints/src/lifetimes.rs b/src/tools/clippy/clippy_lints/src/lifetimes.rs
index aef253303a8f..54c316358a14 100644
--- a/src/tools/clippy/clippy_lints/src/lifetimes.rs
+++ b/src/tools/clippy/clippy_lints/src/lifetimes.rs
@@ -6,11 +6,12 @@ use rustc_hir::intravisit::{
     walk_fn_decl, walk_generic_param, walk_generics, walk_impl_item_ref, walk_item, walk_param_bound,
     walk_poly_trait_ref, walk_trait_ref, walk_ty, Visitor,
 };
+use rustc_hir::lang_items;
 use rustc_hir::FnRetTy::Return;
 use rustc_hir::{
     BareFnTy, BodyId, FnDecl, GenericArg, GenericBound, GenericParam, GenericParamKind, Generics, Impl, ImplItem,
-    ImplItemKind, Item, ItemKind, LangItem, Lifetime, LifetimeName, ParamName, PolyTraitRef, PredicateOrigin, TraitFn,
-    TraitItem, TraitItemKind, Ty, TyKind, WherePredicate,
+    ImplItemKind, Item, ItemKind, Lifetime, LifetimeName, ParamName, PolyTraitRef, PredicateOrigin, TraitFn, TraitItem,
+    TraitItemKind, Ty, TyKind, WherePredicate,
 };
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::hir::nested_filter as middle_nested_filter;
@@ -102,7 +103,7 @@ impl<'tcx> LateLintPass<'tcx> for Lifetimes {
 
     fn check_impl_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx ImplItem<'_>) {
         if let ImplItemKind::Fn(ref sig, id) = item.kind {
-            let report_extra_lifetimes = trait_ref_of_method(cx, item.def_id.def_id).is_none();
+            let report_extra_lifetimes = trait_ref_of_method(cx, item.owner_id.def_id).is_none();
             check_fn_inner(
                 cx,
                 sig.decl,
@@ -364,8 +365,6 @@ fn unique_lifetimes(lts: &[RefLt]) -> usize {
     lts.iter().collect::<FxHashSet<_>>().len()
 }
 
-const CLOSURE_TRAIT_BOUNDS: [LangItem; 3] = [LangItem::Fn, LangItem::FnMut, LangItem::FnOnce];
-
 /// A visitor usable for `rustc_front::visit::walk_ty()`.
 struct RefVisitor<'a, 'tcx> {
     cx: &'a LateContext<'tcx>,
@@ -424,12 +423,8 @@ impl<'a, 'tcx> Visitor<'tcx> for RefVisitor<'a, 'tcx> {
 
     fn visit_poly_trait_ref(&mut self, poly_tref: &'tcx PolyTraitRef<'tcx>) {
         let trait_ref = &poly_tref.trait_ref;
-        if CLOSURE_TRAIT_BOUNDS.iter().any(|&item| {
-            self.cx
-                .tcx
-                .lang_items()
-                .require(item)
-                .map_or(false, |id| Some(id) == trait_ref.trait_def_id())
+        if let Some(id) = trait_ref.trait_def_id() && lang_items::FN_TRAITS.iter().any(|&item| {
+            self.cx.tcx.lang_items().get(item) == Some(id)
         }) {
             let mut sub_visitor = RefVisitor::new(self.cx);
             sub_visitor.visit_trait_ref(trait_ref);
diff --git a/src/tools/clippy/clippy_lints/src/loops/needless_range_loop.rs b/src/tools/clippy/clippy_lints/src/loops/needless_range_loop.rs
index 00cfc6d49f19..27ba27202bf7 100644
--- a/src/tools/clippy/clippy_lints/src/loops/needless_range_loop.rs
+++ b/src/tools/clippy/clippy_lints/src/loops/needless_range_loop.rs
@@ -3,7 +3,7 @@ use clippy_utils::diagnostics::{multispan_sugg, span_lint_and_then};
 use clippy_utils::source::snippet;
 use clippy_utils::ty::has_iter_method;
 use clippy_utils::visitors::is_local_used;
-use clippy_utils::{contains_name, higher, is_integer_const, match_trait_method, paths, sugg, SpanlessEq};
+use clippy_utils::{contains_name, higher, is_integer_const, sugg, SpanlessEq};
 use if_chain::if_chain;
 use rustc_ast::ast;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
@@ -263,7 +263,8 @@ impl<'a, 'tcx> VarVisitor<'a, 'tcx> {
                 match res {
                     Res::Local(hir_id) => {
                         let parent_def_id = self.cx.tcx.hir().get_parent_item(expr.hir_id);
-                        let extent = self.cx
+                        let extent = self
+                            .cx
                             .tcx
                             .region_scope_tree(parent_def_id)
                             .var_scope(hir_id.local_id)
@@ -274,11 +275,12 @@ impl<'a, 'tcx> VarVisitor<'a, 'tcx> {
                                 (Some(extent), self.cx.typeck_results().node_type(seqexpr.hir_id)),
                             );
                         } else {
-                            self.indexed_indirectly.insert(seqvar.segments[0].ident.name, Some(extent));
+                            self.indexed_indirectly
+                                .insert(seqvar.segments[0].ident.name, Some(extent));
                         }
-                        return false;  // no need to walk further *on the variable*
-                    }
-                    Res::Def(DefKind::Static (_)| DefKind::Const, ..) => {
+                        return false; // no need to walk further *on the variable*
+                    },
+                    Res::Def(DefKind::Static(_) | DefKind::Const, ..) => {
                         if index_used_directly {
                             self.indexed_directly.insert(
                                 seqvar.segments[0].ident.name,
@@ -287,8 +289,8 @@ impl<'a, 'tcx> VarVisitor<'a, 'tcx> {
                         } else {
                             self.indexed_indirectly.insert(seqvar.segments[0].ident.name, None);
                         }
-                        return false;  // no need to walk further *on the variable*
-                    }
+                        return false; // no need to walk further *on the variable*
+                    },
                     _ => (),
                 }
             }
@@ -302,17 +304,26 @@ impl<'a, 'tcx> Visitor<'tcx> for VarVisitor<'a, 'tcx> {
         if_chain! {
             // a range index op
             if let ExprKind::MethodCall(meth, args_0, [args_1, ..], _) = &expr.kind;
-            if (meth.ident.name == sym::index && match_trait_method(self.cx, expr, &paths::INDEX))
-                || (meth.ident.name == sym::index_mut && match_trait_method(self.cx, expr, &paths::INDEX_MUT));
+            if let Some(trait_id) = self
+                .cx
+                .typeck_results()
+                .type_dependent_def_id(expr.hir_id)
+                .and_then(|def_id| self.cx.tcx.trait_of_item(def_id));
+            if (meth.ident.name == sym::index && self.cx.tcx.lang_items().index_trait() == Some(trait_id))
+                || (meth.ident.name == sym::index_mut && self.cx.tcx.lang_items().index_mut_trait() == Some(trait_id));
             if !self.check(args_1, args_0, expr);
-            then { return }
+            then {
+                return;
+            }
         }
 
         if_chain! {
             // an index op
             if let ExprKind::Index(seqexpr, idx) = expr.kind;
             if !self.check(idx, seqexpr, expr);
-            then { return }
+            then {
+                return;
+            }
         }
 
         if_chain! {
diff --git a/src/tools/clippy/clippy_lints/src/loops/while_let_on_iterator.rs b/src/tools/clippy/clippy_lints/src/loops/while_let_on_iterator.rs
index 153f97e4e66c..55989f8a4465 100644
--- a/src/tools/clippy/clippy_lints/src/loops/while_let_on_iterator.rs
+++ b/src/tools/clippy/clippy_lints/src/loops/while_let_on_iterator.rs
@@ -331,9 +331,8 @@ fn needs_mutable_borrow(cx: &LateContext<'_>, iter_expr: &IterExpr, loop_expr: &
     }
 
     if let Some(e) = get_enclosing_loop_or_multi_call_closure(cx, loop_expr) {
-        let local_id = match iter_expr.path {
-            Res::Local(id) => id,
-            _ => return true,
+        let Res::Local(local_id) = iter_expr.path else {
+            return true
         };
         let mut v = NestedLoopVisitor {
             cx,
diff --git a/src/tools/clippy/clippy_lints/src/manual_async_fn.rs b/src/tools/clippy/clippy_lints/src/manual_async_fn.rs
index 9a0a26c0991b..090f9f8ff73c 100644
--- a/src/tools/clippy/clippy_lints/src/manual_async_fn.rs
+++ b/src/tools/clippy/clippy_lints/src/manual_async_fn.rs
@@ -1,6 +1,5 @@
 use clippy_utils::diagnostics::span_lint_and_then;
-use clippy_utils::match_function_call;
-use clippy_utils::paths::FUTURE_FROM_GENERATOR;
+use clippy_utils::match_function_call_with_def_id;
 use clippy_utils::source::{position_before_rarrow, snippet_block, snippet_opt};
 use if_chain::if_chain;
 use rustc_errors::Applicability;
@@ -140,9 +139,9 @@ fn future_output_ty<'tcx>(trait_ref: &'tcx TraitRef<'tcx>) -> Option<&'tcx Ty<'t
         if args.bindings.len() == 1;
         let binding = &args.bindings[0];
         if binding.ident.name == sym::Output;
-        if let TypeBindingKind::Equality{term: Term::Ty(output)} = binding.kind;
+        if let TypeBindingKind::Equality { term: Term::Ty(output) } = binding.kind;
         then {
-            return Some(output)
+            return Some(output);
         }
     }
 
@@ -175,9 +174,16 @@ fn captures_all_lifetimes(inputs: &[Ty<'_>], output_lifetimes: &[LifetimeName])
 fn desugared_async_block<'tcx>(cx: &LateContext<'tcx>, block: &'tcx Block<'tcx>) -> Option<&'tcx Body<'tcx>> {
     if_chain! {
         if let Some(block_expr) = block.expr;
-        if let Some(args) = match_function_call(cx, block_expr, &FUTURE_FROM_GENERATOR);
+        if let Some(args) = cx
+            .tcx
+            .lang_items()
+            .from_generator_fn()
+            .and_then(|def_id| match_function_call_with_def_id(cx, block_expr, def_id));
         if args.len() == 1;
-        if let Expr{kind: ExprKind::Closure(&Closure { body, .. }), ..} = args[0];
+        if let Expr {
+            kind: ExprKind::Closure(&Closure { body, .. }),
+            ..
+        } = args[0];
         let closure_body = cx.tcx.hir().body(body);
         if closure_body.generator_kind == Some(GeneratorKind::Async(AsyncGeneratorKind::Block));
         then {
diff --git a/src/tools/clippy/clippy_lints/src/manual_clamp.rs b/src/tools/clippy/clippy_lints/src/manual_clamp.rs
index ece4df95505c..02dc8755dd61 100644
--- a/src/tools/clippy/clippy_lints/src/manual_clamp.rs
+++ b/src/tools/clippy/clippy_lints/src/manual_clamp.rs
@@ -12,9 +12,9 @@ use std::ops::Deref;
 
 use clippy_utils::{
     diagnostics::{span_lint_and_then, span_lint_hir_and_then},
-    eq_expr_value, get_trait_def_id,
+    eq_expr_value,
     higher::If,
-    is_diag_trait_item, is_trait_method, meets_msrv, msrvs, path_res, path_to_local_id, paths, peel_blocks,
+    is_diag_trait_item, is_trait_method, meets_msrv, msrvs, path_res, path_to_local_id, peel_blocks,
     peel_blocks_with_stmt,
     sugg::Sugg,
     ty::implements_trait,
@@ -190,7 +190,11 @@ impl TypeClampability {
     fn is_clampable<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>) -> Option<TypeClampability> {
         if ty.is_floating_point() {
             Some(TypeClampability::Float)
-        } else if get_trait_def_id(cx, &paths::ORD).map_or(false, |id| implements_trait(cx, ty, id, &[])) {
+        } else if cx
+            .tcx
+            .get_diagnostic_item(sym::Ord)
+            .map_or(false, |id| implements_trait(cx, ty, id, &[]))
+        {
             Some(TypeClampability::Ord)
         } else {
             None
diff --git a/src/tools/clippy/clippy_lints/src/manual_non_exhaustive.rs b/src/tools/clippy/clippy_lints/src/manual_non_exhaustive.rs
index 6a42275322b4..6806c1466968 100644
--- a/src/tools/clippy/clippy_lints/src/manual_non_exhaustive.rs
+++ b/src/tools/clippy/clippy_lints/src/manual_non_exhaustive.rs
@@ -166,7 +166,7 @@ impl<'tcx> LateLintPass<'tcx> for ManualNonExhaustiveEnum {
             if let Some((id, span)) = iter.next()
                 && iter.next().is_none()
             {
-                self.potential_enums.push((item.def_id.def_id, id, item.span, span));
+                self.potential_enums.push((item.owner_id.def_id, id, item.span, span));
             }
         }
     }
diff --git a/src/tools/clippy/clippy_lints/src/manual_retain.rs b/src/tools/clippy/clippy_lints/src/manual_retain.rs
index 3181bc86d179..6abbab278feb 100644
--- a/src/tools/clippy/clippy_lints/src/manual_retain.rs
+++ b/src/tools/clippy/clippy_lints/src/manual_retain.rs
@@ -92,7 +92,7 @@ fn check_into_iter(
         && match_def_path(cx, filter_def_id, &paths::CORE_ITER_FILTER)
         && let hir::ExprKind::MethodCall(_, struct_expr, [], _) = &into_iter_expr.kind
         && let Some(into_iter_def_id) = cx.typeck_results().type_dependent_def_id(into_iter_expr.hir_id)
-        && cx.tcx.lang_items().require(hir::LangItem::IntoIterIntoIter).ok() == Some(into_iter_def_id)
+        && Some(into_iter_def_id) == cx.tcx.lang_items().into_iter_fn()
         && match_acceptable_type(cx, left_expr, msrv)
         && SpanlessEq::new(cx).eq_expr(left_expr, struct_expr) {
         suggest(cx, parent_expr, left_expr, target_expr);
diff --git a/src/tools/clippy/clippy_lints/src/matches/collapsible_match.rs b/src/tools/clippy/clippy_lints/src/matches/collapsible_match.rs
index fd14d868df34..33a052c41a38 100644
--- a/src/tools/clippy/clippy_lints/src/matches/collapsible_match.rs
+++ b/src/tools/clippy/clippy_lints/src/matches/collapsible_match.rs
@@ -1,5 +1,6 @@
 use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::higher::IfLetOrMatch;
+use clippy_utils::source::snippet;
 use clippy_utils::visitors::is_local_used;
 use clippy_utils::{
     is_res_lang_ctor, is_unit_expr, path_to_local, peel_blocks_with_stmt, peel_ref_operators, SpanlessEq,
@@ -63,7 +64,8 @@ fn check_arm<'tcx>(
         if !pat_contains_or(inner_then_pat);
         // the binding must come from the pattern of the containing match arm
         // ..<local>.. => match <local> { .. }
-        if let Some(binding_span) = find_pat_binding(outer_pat, binding_id);
+        if let (Some(binding_span), is_innermost_parent_pat_struct)
+            = find_pat_binding_and_is_innermost_parent_pat_struct(outer_pat, binding_id);
         // the "else" branches must be equal
         if match (outer_else_body, inner_else_body) {
             (None, None) => true,
@@ -88,6 +90,13 @@ fn check_arm<'tcx>(
                 if matches!(inner, IfLetOrMatch::Match(..)) { "match" } else { "if let" },
                 if outer_is_match { "match" } else { "if let" },
             );
+            // collapsing patterns need an explicit field name in struct pattern matching
+            // ex: Struct {x: Some(1)}
+            let replace_msg = if is_innermost_parent_pat_struct {
+                format!(", prefixed by {}:", snippet(cx, binding_span, "their field name"))
+            } else {
+                String::new()
+            };
             span_lint_and_then(
                 cx,
                 COLLAPSIBLE_MATCH,
@@ -96,7 +105,7 @@ fn check_arm<'tcx>(
                 |diag| {
                     let mut help_span = MultiSpan::from_spans(vec![binding_span, inner_then_pat.span]);
                     help_span.push_span_label(binding_span, "replace this binding");
-                    help_span.push_span_label(inner_then_pat.span, "with this pattern");
+                    help_span.push_span_label(inner_then_pat.span, format!("with this pattern{replace_msg}"));
                     diag.span_help(help_span, "the outer pattern can be modified to include the inner pattern");
                 },
             );
@@ -117,8 +126,9 @@ fn arm_is_wild_like(cx: &LateContext<'_>, arm: &Arm<'_>) -> bool {
     }
 }
 
-fn find_pat_binding(pat: &Pat<'_>, hir_id: HirId) -> Option<Span> {
+fn find_pat_binding_and_is_innermost_parent_pat_struct(pat: &Pat<'_>, hir_id: HirId) -> (Option<Span>, bool) {
     let mut span = None;
+    let mut is_innermost_parent_pat_struct = false;
     pat.walk_short(|p| match &p.kind {
         // ignore OR patterns
         PatKind::Or(_) => false,
@@ -129,9 +139,12 @@ fn find_pat_binding(pat: &Pat<'_>, hir_id: HirId) -> Option<Span> {
             }
             !found
         },
-        _ => true,
+        _ => {
+            is_innermost_parent_pat_struct = matches!(p.kind, PatKind::Struct(..));
+            true
+        },
     });
-    span
+    (span, is_innermost_parent_pat_struct)
 }
 
 fn pat_contains_or(pat: &Pat<'_>) -> bool {
diff --git a/src/tools/clippy/clippy_lints/src/matches/manual_filter.rs b/src/tools/clippy/clippy_lints/src/matches/manual_filter.rs
new file mode 100644
index 000000000000..66ba1f6f9c55
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/matches/manual_filter.rs
@@ -0,0 +1,153 @@
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::ty::is_type_diagnostic_item;
+use clippy_utils::visitors::contains_unsafe_block;
+use clippy_utils::{is_res_lang_ctor, path_res, path_to_local_id};
+
+use rustc_hir::LangItem::OptionSome;
+use rustc_hir::{Arm, Expr, ExprKind, HirId, Pat, PatKind};
+use rustc_lint::LateContext;
+use rustc_span::{sym, SyntaxContext};
+
+use super::manual_utils::{check_with, SomeExpr};
+use super::MANUAL_FILTER;
+
+// Function called on the <expr> of `[&+]Some((ref | ref mut) x) => <expr>`
+// Need to check if it's of the form `<expr>=if <cond> {<then_expr>} else {<else_expr>}`
+// AND that only one `then/else_expr` resolves to `Some(x)` while the other resolves to `None`
+// return the `cond` expression if so.
+fn get_cond_expr<'tcx>(
+    cx: &LateContext<'tcx>,
+    pat: &Pat<'_>,
+    expr: &'tcx Expr<'_>,
+    ctxt: SyntaxContext,
+) -> Option<SomeExpr<'tcx>> {
+    if_chain! {
+        if let Some(block_expr) = peels_blocks_incl_unsafe_opt(expr);
+        if let ExprKind::If(cond, then_expr, Some(else_expr)) = block_expr.kind;
+        if let PatKind::Binding(_,target, ..) = pat.kind;
+        if let (then_visitor, else_visitor)
+            = (is_some_expr(cx, target, ctxt, then_expr),
+                is_some_expr(cx, target, ctxt, else_expr));
+        if then_visitor != else_visitor; // check that one expr resolves to `Some(x)`, the other to `None`
+        then {
+            return Some(SomeExpr {
+                    expr: peels_blocks_incl_unsafe(cond.peel_drop_temps()),
+                    needs_unsafe_block: contains_unsafe_block(cx, expr),
+                    needs_negated: !then_visitor // if the `then_expr` resolves to `None`, need to negate the cond
+                })
+            }
+    };
+    None
+}
+
+fn peels_blocks_incl_unsafe_opt<'a>(expr: &'a Expr<'a>) -> Option<&'a Expr<'a>> {
+    // we don't want to use `peel_blocks` here because we don't care if the block is unsafe, it's
+    // checked by `contains_unsafe_block`
+    if let ExprKind::Block(block, None) = expr.kind {
+        if block.stmts.is_empty() {
+            return block.expr;
+        }
+    };
+    None
+}
+
+fn peels_blocks_incl_unsafe<'a>(expr: &'a Expr<'a>) -> &'a Expr<'a> {
+    peels_blocks_incl_unsafe_opt(expr).unwrap_or(expr)
+}
+
+// function called for each <expr> expression:
+// Some(x) => if <cond> {
+//    <expr>
+// } else {
+//    <expr>
+// }
+// Returns true if <expr> resolves to `Some(x)`, `false` otherwise
+fn is_some_expr<'tcx>(cx: &LateContext<'_>, target: HirId, ctxt: SyntaxContext, expr: &'tcx Expr<'_>) -> bool {
+    if let Some(inner_expr) = peels_blocks_incl_unsafe_opt(expr) {
+        // there can be not statements in the block as they would be removed when switching to `.filter`
+        if let ExprKind::Call(callee, [arg]) = inner_expr.kind {
+            return ctxt == expr.span.ctxt()
+                && is_res_lang_ctor(cx, path_res(cx, callee), OptionSome)
+                && path_to_local_id(arg, target);
+        }
+    };
+    false
+}
+
+// given the closure: `|<pattern>| <expr>`
+// returns `|&<pattern>| <expr>`
+fn add_ampersand_if_copy(body_str: String, has_copy_trait: bool) -> String {
+    if has_copy_trait {
+        let mut with_ampersand = body_str;
+        with_ampersand.insert(1, '&');
+        with_ampersand
+    } else {
+        body_str
+    }
+}
+
+pub(super) fn check_match<'tcx>(
+    cx: &LateContext<'tcx>,
+    scrutinee: &'tcx Expr<'_>,
+    arms: &'tcx [Arm<'_>],
+    expr: &'tcx Expr<'_>,
+) {
+    let ty = cx.typeck_results().expr_ty(expr);
+    if is_type_diagnostic_item(cx, ty, sym::Option)
+    && let [first_arm, second_arm] = arms
+    && first_arm.guard.is_none()
+    && second_arm.guard.is_none()
+         {
+            check(cx, expr, scrutinee, first_arm.pat, first_arm.body, Some(second_arm.pat), second_arm.body);
+        }
+}
+
+pub(super) fn check_if_let<'tcx>(
+    cx: &LateContext<'tcx>,
+    expr: &'tcx Expr<'_>,
+    let_pat: &'tcx Pat<'_>,
+    let_expr: &'tcx Expr<'_>,
+    then_expr: &'tcx Expr<'_>,
+    else_expr: &'tcx Expr<'_>,
+) {
+    check(cx, expr, let_expr, let_pat, then_expr, None, else_expr);
+}
+
+fn check<'tcx>(
+    cx: &LateContext<'tcx>,
+    expr: &'tcx Expr<'_>,
+    scrutinee: &'tcx Expr<'_>,
+    then_pat: &'tcx Pat<'_>,
+    then_body: &'tcx Expr<'_>,
+    else_pat: Option<&'tcx Pat<'_>>,
+    else_body: &'tcx Expr<'_>,
+) {
+    if let Some(sugg_info) = check_with(
+        cx,
+        expr,
+        scrutinee,
+        then_pat,
+        then_body,
+        else_pat,
+        else_body,
+        get_cond_expr,
+    ) {
+        let body_str = add_ampersand_if_copy(sugg_info.body_str, sugg_info.scrutinee_impl_copy);
+        span_lint_and_sugg(
+            cx,
+            MANUAL_FILTER,
+            expr.span,
+            "manual implementation of `Option::filter`",
+            "try this",
+            if sugg_info.needs_brackets {
+                format!(
+                    "{{ {}{}.filter({body_str}) }}",
+                    sugg_info.scrutinee_str, sugg_info.as_ref_str
+                )
+            } else {
+                format!("{}{}.filter({body_str})", sugg_info.scrutinee_str, sugg_info.as_ref_str)
+            },
+            sugg_info.app,
+        );
+    }
+}
diff --git a/src/tools/clippy/clippy_lints/src/matches/manual_map.rs b/src/tools/clippy/clippy_lints/src/matches/manual_map.rs
index 76f5e1c941c7..aaba239677ff 100644
--- a/src/tools/clippy/clippy_lints/src/matches/manual_map.rs
+++ b/src/tools/clippy/clippy_lints/src/matches/manual_map.rs
@@ -1,22 +1,13 @@
-use crate::{map_unit_fn::OPTION_MAP_UNIT_FN, matches::MATCH_AS_REF};
-use clippy_utils::diagnostics::span_lint_and_sugg;
-use clippy_utils::source::{snippet_with_applicability, snippet_with_context};
-use clippy_utils::ty::{is_type_diagnostic_item, peel_mid_ty_refs_is_mutable, type_is_unsafe_function};
-use clippy_utils::{
-    can_move_expr_to_closure, is_else_clause, is_lint_allowed, is_res_lang_ctor, path_res, path_to_local_id,
-    peel_blocks, peel_hir_expr_refs, peel_hir_expr_while, CaptureKind,
-};
-use rustc_ast::util::parser::PREC_POSTFIX;
-use rustc_errors::Applicability;
-use rustc_hir::LangItem::{OptionNone, OptionSome};
-use rustc_hir::{
-    def::Res, Arm, BindingAnnotation, Block, BlockCheckMode, Expr, ExprKind, HirId, Mutability, Pat, PatKind, Path,
-    QPath, UnsafeSource,
-};
-use rustc_lint::LateContext;
-use rustc_span::{sym, SyntaxContext};
-
+use super::manual_utils::{check_with, SomeExpr};
 use super::MANUAL_MAP;
+use clippy_utils::diagnostics::span_lint_and_sugg;
+
+use clippy_utils::{is_res_lang_ctor, path_res};
+
+use rustc_hir::LangItem::OptionSome;
+use rustc_hir::{Arm, Block, BlockCheckMode, Expr, ExprKind, Pat, UnsafeSource};
+use rustc_lint::LateContext;
+use rustc_span::SyntaxContext;
 
 pub(super) fn check_match<'tcx>(
     cx: &LateContext<'tcx>,
@@ -43,7 +34,6 @@ pub(super) fn check_if_let<'tcx>(
     check(cx, expr, let_expr, let_pat, then_expr, None, else_expr);
 }
 
-#[expect(clippy::too_many_lines)]
 fn check<'tcx>(
     cx: &LateContext<'tcx>,
     expr: &'tcx Expr<'_>,
@@ -53,254 +43,74 @@ fn check<'tcx>(
     else_pat: Option<&'tcx Pat<'_>>,
     else_body: &'tcx Expr<'_>,
 ) {
-    let (scrutinee_ty, ty_ref_count, ty_mutability) =
-        peel_mid_ty_refs_is_mutable(cx.typeck_results().expr_ty(scrutinee));
-    if !(is_type_diagnostic_item(cx, scrutinee_ty, sym::Option)
-        && is_type_diagnostic_item(cx, cx.typeck_results().expr_ty(expr), sym::Option))
-    {
-        return;
-    }
-
-    let expr_ctxt = expr.span.ctxt();
-    let (some_expr, some_pat, pat_ref_count, is_wild_none) = match (
-        try_parse_pattern(cx, then_pat, expr_ctxt),
-        else_pat.map_or(Some(OptionPat::Wild), |p| try_parse_pattern(cx, p, expr_ctxt)),
-    ) {
-        (Some(OptionPat::Wild), Some(OptionPat::Some { pattern, ref_count })) if is_none_expr(cx, then_body) => {
-            (else_body, pattern, ref_count, true)
-        },
-        (Some(OptionPat::None), Some(OptionPat::Some { pattern, ref_count })) if is_none_expr(cx, then_body) => {
-            (else_body, pattern, ref_count, false)
-        },
-        (Some(OptionPat::Some { pattern, ref_count }), Some(OptionPat::Wild)) if is_none_expr(cx, else_body) => {
-            (then_body, pattern, ref_count, true)
-        },
-        (Some(OptionPat::Some { pattern, ref_count }), Some(OptionPat::None)) if is_none_expr(cx, else_body) => {
-            (then_body, pattern, ref_count, false)
-        },
-        _ => return,
-    };
-
-    // Top level or patterns aren't allowed in closures.
-    if matches!(some_pat.kind, PatKind::Or(_)) {
-        return;
-    }
-
-    let some_expr = match get_some_expr(cx, some_expr, false, expr_ctxt) {
-        Some(expr) => expr,
-        None => return,
-    };
-
-    // These two lints will go back and forth with each other.
-    if cx.typeck_results().expr_ty(some_expr.expr) == cx.tcx.types.unit
-        && !is_lint_allowed(cx, OPTION_MAP_UNIT_FN, expr.hir_id)
-    {
-        return;
-    }
-
-    // `map` won't perform any adjustments.
-    if !cx.typeck_results().expr_adjustments(some_expr.expr).is_empty() {
-        return;
-    }
-
-    // Determine which binding mode to use.
-    let explicit_ref = some_pat.contains_explicit_ref_binding();
-    let binding_ref = explicit_ref.or_else(|| (ty_ref_count != pat_ref_count).then_some(ty_mutability));
-
-    let as_ref_str = match binding_ref {
-        Some(Mutability::Mut) => ".as_mut()",
-        Some(Mutability::Not) => ".as_ref()",
-        None => "",
-    };
-
-    match can_move_expr_to_closure(cx, some_expr.expr) {
-        Some(captures) => {
-            // Check if captures the closure will need conflict with borrows made in the scrutinee.
-            // TODO: check all the references made in the scrutinee expression. This will require interacting
-            // with the borrow checker. Currently only `<local>[.<field>]*` is checked for.
-            if let Some(binding_ref_mutability) = binding_ref {
-                let e = peel_hir_expr_while(scrutinee, |e| match e.kind {
-                    ExprKind::Field(e, _) | ExprKind::AddrOf(_, _, e) => Some(e),
-                    _ => None,
-                });
-                if let ExprKind::Path(QPath::Resolved(None, Path { res: Res::Local(l), .. })) = e.kind {
-                    match captures.get(l) {
-                        Some(CaptureKind::Value | CaptureKind::Ref(Mutability::Mut)) => return,
-                        Some(CaptureKind::Ref(Mutability::Not)) if binding_ref_mutability == Mutability::Mut => {
-                            return;
-                        },
-                        Some(CaptureKind::Ref(Mutability::Not)) | None => (),
-                    }
-                }
-            }
-        },
-        None => return,
-    };
-
-    let mut app = Applicability::MachineApplicable;
-
-    // Remove address-of expressions from the scrutinee. Either `as_ref` will be called, or
-    // it's being passed by value.
-    let scrutinee = peel_hir_expr_refs(scrutinee).0;
-    let (scrutinee_str, _) = snippet_with_context(cx, scrutinee.span, expr_ctxt, "..", &mut app);
-    let scrutinee_str = if scrutinee.span.ctxt() == expr.span.ctxt() && scrutinee.precedence().order() < PREC_POSTFIX {
-        format!("({scrutinee_str})")
-    } else {
-        scrutinee_str.into()
-    };
-
-    let body_str = if let PatKind::Binding(annotation, id, some_binding, None) = some_pat.kind {
-        if_chain! {
-            if !some_expr.needs_unsafe_block;
-            if let Some(func) = can_pass_as_func(cx, id, some_expr.expr);
-            if func.span.ctxt() == some_expr.expr.span.ctxt();
-            then {
-                snippet_with_applicability(cx, func.span, "..", &mut app).into_owned()
-            } else {
-                if path_to_local_id(some_expr.expr, id)
-                    && !is_lint_allowed(cx, MATCH_AS_REF, expr.hir_id)
-                    && binding_ref.is_some()
-                {
-                    return;
-                }
-
-                // `ref` and `ref mut` annotations were handled earlier.
-                let annotation = if matches!(annotation, BindingAnnotation::MUT) {
-                    "mut "
-                } else {
-                    ""
-                };
-                let expr_snip = snippet_with_context(cx, some_expr.expr.span, expr_ctxt, "..", &mut app).0;
-                if some_expr.needs_unsafe_block {
-                    format!("|{annotation}{some_binding}| unsafe {{ {expr_snip} }}")
-                } else {
-                    format!("|{annotation}{some_binding}| {expr_snip}")
-                }
-            }
-        }
-    } else if !is_wild_none && explicit_ref.is_none() {
-        // TODO: handle explicit reference annotations.
-        let pat_snip = snippet_with_context(cx, some_pat.span, expr_ctxt, "..", &mut app).0;
-        let expr_snip = snippet_with_context(cx, some_expr.expr.span, expr_ctxt, "..", &mut app).0;
-        if some_expr.needs_unsafe_block {
-            format!("|{pat_snip}| unsafe {{ {expr_snip} }}")
-        } else {
-            format!("|{pat_snip}| {expr_snip}")
-        }
-    } else {
-        // Refutable bindings and mixed reference annotations can't be handled by `map`.
-        return;
-    };
-
-    span_lint_and_sugg(
+    if let Some(sugg_info) = check_with(
         cx,
-        MANUAL_MAP,
-        expr.span,
-        "manual implementation of `Option::map`",
-        "try this",
-        if else_pat.is_none() && is_else_clause(cx.tcx, expr) {
-            format!("{{ {scrutinee_str}{as_ref_str}.map({body_str}) }}")
-        } else {
-            format!("{scrutinee_str}{as_ref_str}.map({body_str})")
-        },
-        app,
-    );
-}
-
-// Checks whether the expression could be passed as a function, or whether a closure is needed.
-// Returns the function to be passed to `map` if it exists.
-fn can_pass_as_func<'tcx>(cx: &LateContext<'tcx>, binding: HirId, expr: &'tcx Expr<'_>) -> Option<&'tcx Expr<'tcx>> {
-    match expr.kind {
-        ExprKind::Call(func, [arg])
-            if path_to_local_id(arg, binding)
-                && cx.typeck_results().expr_adjustments(arg).is_empty()
-                && !type_is_unsafe_function(cx, cx.typeck_results().expr_ty(func).peel_refs()) =>
-        {
-            Some(func)
-        },
-        _ => None,
-    }
-}
-
-enum OptionPat<'a> {
-    Wild,
-    None,
-    Some {
-        // The pattern contained in the `Some` tuple.
-        pattern: &'a Pat<'a>,
-        // The number of references before the `Some` tuple.
-        // e.g. `&&Some(_)` has a ref count of 2.
-        ref_count: usize,
-    },
-}
-
-struct SomeExpr<'tcx> {
-    expr: &'tcx Expr<'tcx>,
-    needs_unsafe_block: bool,
-}
-
-// Try to parse into a recognized `Option` pattern.
-// i.e. `_`, `None`, `Some(..)`, or a reference to any of those.
-fn try_parse_pattern<'tcx>(cx: &LateContext<'tcx>, pat: &'tcx Pat<'_>, ctxt: SyntaxContext) -> Option<OptionPat<'tcx>> {
-    fn f<'tcx>(
-        cx: &LateContext<'tcx>,
-        pat: &'tcx Pat<'_>,
-        ref_count: usize,
-        ctxt: SyntaxContext,
-    ) -> Option<OptionPat<'tcx>> {
-        match pat.kind {
-            PatKind::Wild => Some(OptionPat::Wild),
-            PatKind::Ref(pat, _) => f(cx, pat, ref_count + 1, ctxt),
-            PatKind::Path(ref qpath) if is_res_lang_ctor(cx, cx.qpath_res(qpath, pat.hir_id), OptionNone) => {
-                Some(OptionPat::None)
+        expr,
+        scrutinee,
+        then_pat,
+        then_body,
+        else_pat,
+        else_body,
+        get_some_expr,
+    ) {
+        span_lint_and_sugg(
+            cx,
+            MANUAL_MAP,
+            expr.span,
+            "manual implementation of `Option::map`",
+            "try this",
+            if sugg_info.needs_brackets {
+                format!(
+                    "{{ {}{}.map({}) }}",
+                    sugg_info.scrutinee_str, sugg_info.as_ref_str, sugg_info.body_str
+                )
+            } else {
+                format!(
+                    "{}{}.map({})",
+                    sugg_info.scrutinee_str, sugg_info.as_ref_str, sugg_info.body_str
+                )
             },
-            PatKind::TupleStruct(ref qpath, [pattern], _)
-                if is_res_lang_ctor(cx, cx.qpath_res(qpath, pat.hir_id), OptionSome) && pat.span.ctxt() == ctxt =>
-            {
-                Some(OptionPat::Some { pattern, ref_count })
-            },
-            _ => None,
-        }
+            sugg_info.app,
+        );
     }
-    f(cx, pat, 0, ctxt)
 }
 
 // Checks for an expression wrapped by the `Some` constructor. Returns the contained expression.
 fn get_some_expr<'tcx>(
     cx: &LateContext<'tcx>,
+    _: &'tcx Pat<'_>,
     expr: &'tcx Expr<'_>,
-    needs_unsafe_block: bool,
     ctxt: SyntaxContext,
 ) -> Option<SomeExpr<'tcx>> {
-    // TODO: Allow more complex expressions.
-    match expr.kind {
-        ExprKind::Call(callee, [arg])
-            if ctxt == expr.span.ctxt() && is_res_lang_ctor(cx, path_res(cx, callee), OptionSome) =>
-        {
-            Some(SomeExpr {
-                expr: arg,
-                needs_unsafe_block,
-            })
-        },
-        ExprKind::Block(
-            Block {
-                stmts: [],
-                expr: Some(expr),
-                rules,
-                ..
+    fn get_some_expr_internal<'tcx>(
+        cx: &LateContext<'tcx>,
+        expr: &'tcx Expr<'_>,
+        needs_unsafe_block: bool,
+        ctxt: SyntaxContext,
+    ) -> Option<SomeExpr<'tcx>> {
+        // TODO: Allow more complex expressions.
+        match expr.kind {
+            ExprKind::Call(callee, [arg])
+                if ctxt == expr.span.ctxt() && is_res_lang_ctor(cx, path_res(cx, callee), OptionSome) =>
+            {
+                Some(SomeExpr::new_no_negated(arg, needs_unsafe_block))
             },
-            _,
-        ) => get_some_expr(
-            cx,
-            expr,
-            needs_unsafe_block || *rules == BlockCheckMode::UnsafeBlock(UnsafeSource::UserProvided),
-            ctxt,
-        ),
-        _ => None,
+            ExprKind::Block(
+                Block {
+                    stmts: [],
+                    expr: Some(expr),
+                    rules,
+                    ..
+                },
+                _,
+            ) => get_some_expr_internal(
+                cx,
+                expr,
+                needs_unsafe_block || *rules == BlockCheckMode::UnsafeBlock(UnsafeSource::UserProvided),
+                ctxt,
+            ),
+            _ => None,
+        }
     }
-}
-
-// Checks for the `None` value.
-fn is_none_expr(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
-    is_res_lang_ctor(cx, path_res(cx, peel_blocks(expr)), OptionNone)
+    get_some_expr_internal(cx, expr, false, ctxt)
 }
diff --git a/src/tools/clippy/clippy_lints/src/matches/manual_utils.rs b/src/tools/clippy/clippy_lints/src/matches/manual_utils.rs
new file mode 100644
index 000000000000..5b7644a53832
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/matches/manual_utils.rs
@@ -0,0 +1,277 @@
+use crate::{map_unit_fn::OPTION_MAP_UNIT_FN, matches::MATCH_AS_REF};
+use clippy_utils::source::{snippet_with_applicability, snippet_with_context};
+use clippy_utils::ty::{is_copy, is_type_diagnostic_item, peel_mid_ty_refs_is_mutable, type_is_unsafe_function};
+use clippy_utils::{
+    can_move_expr_to_closure, is_else_clause, is_lint_allowed, is_res_lang_ctor, path_res, path_to_local_id,
+    peel_blocks, peel_hir_expr_refs, peel_hir_expr_while, sugg::Sugg, CaptureKind,
+};
+use rustc_ast::util::parser::PREC_POSTFIX;
+use rustc_errors::Applicability;
+use rustc_hir::LangItem::{OptionNone, OptionSome};
+use rustc_hir::{def::Res, BindingAnnotation, Expr, ExprKind, HirId, Mutability, Pat, PatKind, Path, QPath};
+use rustc_lint::LateContext;
+use rustc_span::{sym, SyntaxContext};
+
+#[expect(clippy::too_many_arguments)]
+#[expect(clippy::too_many_lines)]
+pub(super) fn check_with<'tcx, F>(
+    cx: &LateContext<'tcx>,
+    expr: &'tcx Expr<'_>,
+    scrutinee: &'tcx Expr<'_>,
+    then_pat: &'tcx Pat<'_>,
+    then_body: &'tcx Expr<'_>,
+    else_pat: Option<&'tcx Pat<'_>>,
+    else_body: &'tcx Expr<'_>,
+    get_some_expr_fn: F,
+) -> Option<SuggInfo<'tcx>>
+where
+    F: Fn(&LateContext<'tcx>, &'tcx Pat<'_>, &'tcx Expr<'_>, SyntaxContext) -> Option<SomeExpr<'tcx>>,
+{
+    let (scrutinee_ty, ty_ref_count, ty_mutability) =
+        peel_mid_ty_refs_is_mutable(cx.typeck_results().expr_ty(scrutinee));
+    if !(is_type_diagnostic_item(cx, scrutinee_ty, sym::Option)
+        && is_type_diagnostic_item(cx, cx.typeck_results().expr_ty(expr), sym::Option))
+    {
+        return None;
+    }
+
+    let expr_ctxt = expr.span.ctxt();
+    let (some_expr, some_pat, pat_ref_count, is_wild_none) = match (
+        try_parse_pattern(cx, then_pat, expr_ctxt),
+        else_pat.map_or(Some(OptionPat::Wild), |p| try_parse_pattern(cx, p, expr_ctxt)),
+    ) {
+        (Some(OptionPat::Wild), Some(OptionPat::Some { pattern, ref_count })) if is_none_expr(cx, then_body) => {
+            (else_body, pattern, ref_count, true)
+        },
+        (Some(OptionPat::None), Some(OptionPat::Some { pattern, ref_count })) if is_none_expr(cx, then_body) => {
+            (else_body, pattern, ref_count, false)
+        },
+        (Some(OptionPat::Some { pattern, ref_count }), Some(OptionPat::Wild)) if is_none_expr(cx, else_body) => {
+            (then_body, pattern, ref_count, true)
+        },
+        (Some(OptionPat::Some { pattern, ref_count }), Some(OptionPat::None)) if is_none_expr(cx, else_body) => {
+            (then_body, pattern, ref_count, false)
+        },
+        _ => return None,
+    };
+
+    // Top level or patterns aren't allowed in closures.
+    if matches!(some_pat.kind, PatKind::Or(_)) {
+        return None;
+    }
+
+    let Some(some_expr) = get_some_expr_fn(cx, some_pat, some_expr, expr_ctxt) else {
+        return None;
+    };
+
+    // These two lints will go back and forth with each other.
+    if cx.typeck_results().expr_ty(some_expr.expr) == cx.tcx.types.unit
+        && !is_lint_allowed(cx, OPTION_MAP_UNIT_FN, expr.hir_id)
+    {
+        return None;
+    }
+
+    // `map` won't perform any adjustments.
+    if !cx.typeck_results().expr_adjustments(some_expr.expr).is_empty() {
+        return None;
+    }
+
+    // Determine which binding mode to use.
+    let explicit_ref = some_pat.contains_explicit_ref_binding();
+    let binding_ref = explicit_ref.or_else(|| (ty_ref_count != pat_ref_count).then_some(ty_mutability));
+
+    let as_ref_str = match binding_ref {
+        Some(Mutability::Mut) => ".as_mut()",
+        Some(Mutability::Not) => ".as_ref()",
+        None => "",
+    };
+
+    match can_move_expr_to_closure(cx, some_expr.expr) {
+        Some(captures) => {
+            // Check if captures the closure will need conflict with borrows made in the scrutinee.
+            // TODO: check all the references made in the scrutinee expression. This will require interacting
+            // with the borrow checker. Currently only `<local>[.<field>]*` is checked for.
+            if let Some(binding_ref_mutability) = binding_ref {
+                let e = peel_hir_expr_while(scrutinee, |e| match e.kind {
+                    ExprKind::Field(e, _) | ExprKind::AddrOf(_, _, e) => Some(e),
+                    _ => None,
+                });
+                if let ExprKind::Path(QPath::Resolved(None, Path { res: Res::Local(l), .. })) = e.kind {
+                    match captures.get(l) {
+                        Some(CaptureKind::Value | CaptureKind::Ref(Mutability::Mut)) => return None,
+                        Some(CaptureKind::Ref(Mutability::Not)) if binding_ref_mutability == Mutability::Mut => {
+                            return None;
+                        },
+                        Some(CaptureKind::Ref(Mutability::Not)) | None => (),
+                    }
+                }
+            }
+        },
+        None => return None,
+    };
+
+    let mut app = Applicability::MachineApplicable;
+
+    // Remove address-of expressions from the scrutinee. Either `as_ref` will be called, or
+    // it's being passed by value.
+    let scrutinee = peel_hir_expr_refs(scrutinee).0;
+    let (scrutinee_str, _) = snippet_with_context(cx, scrutinee.span, expr_ctxt, "..", &mut app);
+    let scrutinee_str = if scrutinee.span.ctxt() == expr.span.ctxt() && scrutinee.precedence().order() < PREC_POSTFIX {
+        format!("({scrutinee_str})")
+    } else {
+        scrutinee_str.into()
+    };
+
+    let closure_expr_snip = some_expr.to_snippet_with_context(cx, expr_ctxt, &mut app);
+    let body_str = if let PatKind::Binding(annotation, id, some_binding, None) = some_pat.kind {
+        if_chain! {
+            if !some_expr.needs_unsafe_block;
+            if let Some(func) = can_pass_as_func(cx, id, some_expr.expr);
+            if func.span.ctxt() == some_expr.expr.span.ctxt();
+            then {
+                snippet_with_applicability(cx, func.span, "..", &mut app).into_owned()
+            } else {
+                if path_to_local_id(some_expr.expr, id)
+                    && !is_lint_allowed(cx, MATCH_AS_REF, expr.hir_id)
+                    && binding_ref.is_some()
+                {
+                    return None;
+                }
+
+                // `ref` and `ref mut` annotations were handled earlier.
+                let annotation = if matches!(annotation, BindingAnnotation::MUT) {
+                    "mut "
+                } else {
+                    ""
+                };
+
+                if some_expr.needs_unsafe_block {
+                    format!("|{annotation}{some_binding}| unsafe {{ {closure_expr_snip} }}")
+                } else {
+                    format!("|{annotation}{some_binding}| {closure_expr_snip}")
+                }
+            }
+        }
+    } else if !is_wild_none && explicit_ref.is_none() {
+        // TODO: handle explicit reference annotations.
+        let pat_snip = snippet_with_context(cx, some_pat.span, expr_ctxt, "..", &mut app).0;
+        if some_expr.needs_unsafe_block {
+            format!("|{pat_snip}| unsafe {{ {closure_expr_snip} }}")
+        } else {
+            format!("|{pat_snip}| {closure_expr_snip}")
+        }
+    } else {
+        // Refutable bindings and mixed reference annotations can't be handled by `map`.
+        return None;
+    };
+
+    // relies on the fact that Option<T>: Copy where T: copy
+    let scrutinee_impl_copy = is_copy(cx, scrutinee_ty);
+
+    Some(SuggInfo {
+        needs_brackets: else_pat.is_none() && is_else_clause(cx.tcx, expr),
+        scrutinee_impl_copy,
+        scrutinee_str,
+        as_ref_str,
+        body_str,
+        app,
+    })
+}
+
+pub struct SuggInfo<'a> {
+    pub needs_brackets: bool,
+    pub scrutinee_impl_copy: bool,
+    pub scrutinee_str: String,
+    pub as_ref_str: &'a str,
+    pub body_str: String,
+    pub app: Applicability,
+}
+
+// Checks whether the expression could be passed as a function, or whether a closure is needed.
+// Returns the function to be passed to `map` if it exists.
+fn can_pass_as_func<'tcx>(cx: &LateContext<'tcx>, binding: HirId, expr: &'tcx Expr<'_>) -> Option<&'tcx Expr<'tcx>> {
+    match expr.kind {
+        ExprKind::Call(func, [arg])
+            if path_to_local_id(arg, binding)
+                && cx.typeck_results().expr_adjustments(arg).is_empty()
+                && !type_is_unsafe_function(cx, cx.typeck_results().expr_ty(func).peel_refs()) =>
+        {
+            Some(func)
+        },
+        _ => None,
+    }
+}
+
+#[derive(Debug)]
+pub(super) enum OptionPat<'a> {
+    Wild,
+    None,
+    Some {
+        // The pattern contained in the `Some` tuple.
+        pattern: &'a Pat<'a>,
+        // The number of references before the `Some` tuple.
+        // e.g. `&&Some(_)` has a ref count of 2.
+        ref_count: usize,
+    },
+}
+
+pub(super) struct SomeExpr<'tcx> {
+    pub expr: &'tcx Expr<'tcx>,
+    pub needs_unsafe_block: bool,
+    pub needs_negated: bool, // for `manual_filter` lint
+}
+
+impl<'tcx> SomeExpr<'tcx> {
+    pub fn new_no_negated(expr: &'tcx Expr<'tcx>, needs_unsafe_block: bool) -> Self {
+        Self {
+            expr,
+            needs_unsafe_block,
+            needs_negated: false,
+        }
+    }
+
+    pub fn to_snippet_with_context(
+        &self,
+        cx: &LateContext<'tcx>,
+        ctxt: SyntaxContext,
+        app: &mut Applicability,
+    ) -> Sugg<'tcx> {
+        let sugg = Sugg::hir_with_context(cx, self.expr, ctxt, "..", app);
+        if self.needs_negated { !sugg } else { sugg }
+    }
+}
+
+// Try to parse into a recognized `Option` pattern.
+// i.e. `_`, `None`, `Some(..)`, or a reference to any of those.
+pub(super) fn try_parse_pattern<'tcx>(
+    cx: &LateContext<'tcx>,
+    pat: &'tcx Pat<'_>,
+    ctxt: SyntaxContext,
+) -> Option<OptionPat<'tcx>> {
+    fn f<'tcx>(
+        cx: &LateContext<'tcx>,
+        pat: &'tcx Pat<'_>,
+        ref_count: usize,
+        ctxt: SyntaxContext,
+    ) -> Option<OptionPat<'tcx>> {
+        match pat.kind {
+            PatKind::Wild => Some(OptionPat::Wild),
+            PatKind::Ref(pat, _) => f(cx, pat, ref_count + 1, ctxt),
+            PatKind::Path(ref qpath) if is_res_lang_ctor(cx, cx.qpath_res(qpath, pat.hir_id), OptionNone) => {
+                Some(OptionPat::None)
+            },
+            PatKind::TupleStruct(ref qpath, [pattern], _)
+                if is_res_lang_ctor(cx, cx.qpath_res(qpath, pat.hir_id), OptionSome) && pat.span.ctxt() == ctxt =>
+            {
+                Some(OptionPat::Some { pattern, ref_count })
+            },
+            _ => None,
+        }
+    }
+    f(cx, pat, 0, ctxt)
+}
+
+// Checks for the `None` value.
+fn is_none_expr(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
+    is_res_lang_ctor(cx, path_res(cx, peel_blocks(expr)), OptionNone)
+}
diff --git a/src/tools/clippy/clippy_lints/src/matches/match_same_arms.rs b/src/tools/clippy/clippy_lints/src/matches/match_same_arms.rs
index 37049f835775..168c1e4d2e60 100644
--- a/src/tools/clippy/clippy_lints/src/matches/match_same_arms.rs
+++ b/src/tools/clippy/clippy_lints/src/matches/match_same_arms.rs
@@ -221,7 +221,6 @@ fn iter_matching_struct_fields<'a>(
 
 #[expect(clippy::similar_names)]
 impl<'a> NormalizedPat<'a> {
-    #[expect(clippy::too_many_lines)]
     fn from_pat(cx: &LateContext<'_>, arena: &'a DroplessArena, pat: &'a Pat<'_>) -> Self {
         match pat.kind {
             PatKind::Wild | PatKind::Binding(.., None) => Self::Wild,
@@ -235,9 +234,8 @@ impl<'a> NormalizedPat<'a> {
                 Self::Struct(cx.qpath_res(path, pat.hir_id).opt_def_id(), fields)
             },
             PatKind::TupleStruct(ref path, pats, wild_idx) => {
-                let adt = match cx.typeck_results().pat_ty(pat).ty_adt_def() {
-                    Some(x) => x,
-                    None => return Self::Wild,
+                let Some(adt) = cx.typeck_results().pat_ty(pat).ty_adt_def() else {
+                    return Self::Wild
                 };
                 let (var_id, variant) = if adt.is_enum() {
                     match cx.qpath_res(path, pat.hir_id).opt_def_id() {
diff --git a/src/tools/clippy/clippy_lints/src/matches/match_single_binding.rs b/src/tools/clippy/clippy_lints/src/matches/match_single_binding.rs
index 68682cedf1de..1bf8d4e96ad4 100644
--- a/src/tools/clippy/clippy_lints/src/matches/match_single_binding.rs
+++ b/src/tools/clippy/clippy_lints/src/matches/match_single_binding.rs
@@ -58,6 +58,7 @@ pub(crate) fn check<'a>(cx: &LateContext<'a>, ex: &Expr<'a>, arms: &[Arm<'_>], e
                         &snippet_body,
                         &mut applicability,
                         Some(span),
+                        true,
                     );
 
                     span_lint_and_sugg(
@@ -90,6 +91,7 @@ pub(crate) fn check<'a>(cx: &LateContext<'a>, ex: &Expr<'a>, arms: &[Arm<'_>], e
                         &snippet_body,
                         &mut applicability,
                         None,
+                        true,
                     );
                     (expr.span, sugg)
                 },
@@ -107,10 +109,14 @@ pub(crate) fn check<'a>(cx: &LateContext<'a>, ex: &Expr<'a>, arms: &[Arm<'_>], e
         },
         PatKind::Wild => {
             if ex.can_have_side_effects() {
-                let indent = " ".repeat(indent_of(cx, expr.span).unwrap_or(0));
-                let sugg = format!(
-                    "{};\n{indent}{snippet_body}",
-                    snippet_with_applicability(cx, ex.span, "..", &mut applicability)
+                let sugg = sugg_with_curlies(
+                    cx,
+                    (ex, expr),
+                    (bind_names, matched_vars),
+                    &snippet_body,
+                    &mut applicability,
+                    None,
+                    false,
                 );
 
                 span_lint_and_sugg(
@@ -169,6 +175,7 @@ fn sugg_with_curlies<'a>(
     snippet_body: &str,
     applicability: &mut Applicability,
     assignment: Option<Span>,
+    needs_var_binding: bool,
 ) -> String {
     let mut indent = " ".repeat(indent_of(cx, ex.span).unwrap_or(0));
 
@@ -200,9 +207,15 @@ fn sugg_with_curlies<'a>(
         s
     });
 
-    format!(
-        "{cbrace_start}let {} = {};\n{indent}{assignment_str}{snippet_body}{cbrace_end}",
-        snippet_with_applicability(cx, bind_names, "..", applicability),
-        snippet_with_applicability(cx, matched_vars, "..", applicability)
-    )
+    let scrutinee = if needs_var_binding {
+        format!(
+            "let {} = {}",
+            snippet_with_applicability(cx, bind_names, "..", applicability),
+            snippet_with_applicability(cx, matched_vars, "..", applicability)
+        )
+    } else {
+        snippet_with_applicability(cx, matched_vars, "..", applicability).to_string()
+    };
+
+    format!("{cbrace_start}{scrutinee};\n{indent}{assignment_str}{snippet_body}{cbrace_end}")
 }
diff --git a/src/tools/clippy/clippy_lints/src/matches/mod.rs b/src/tools/clippy/clippy_lints/src/matches/mod.rs
index e6b183fc05f2..7d8171ead89e 100644
--- a/src/tools/clippy/clippy_lints/src/matches/mod.rs
+++ b/src/tools/clippy/clippy_lints/src/matches/mod.rs
@@ -1,7 +1,9 @@
 mod collapsible_match;
 mod infallible_destructuring_match;
+mod manual_filter;
 mod manual_map;
 mod manual_unwrap_or;
+mod manual_utils;
 mod match_as_ref;
 mod match_bool;
 mod match_like_matches;
@@ -898,6 +900,34 @@ declare_clippy_lint! {
     "reimplementation of `map`"
 }
 
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks for usages of `match` which could be implemented using `filter`
+    ///
+    /// ### Why is this bad?
+    /// Using the `filter` method is clearer and more concise.
+    ///
+    /// ### Example
+    /// ```rust
+    /// match Some(0) {
+    ///     Some(x) => if x % 2 == 0 {
+    ///                     Some(x)
+    ///                } else {
+    ///                     None
+    ///                 },
+    ///     None => None,
+    /// };
+    /// ```
+    /// Use instead:
+    /// ```rust
+    /// Some(0).filter(|&x| x % 2 == 0);
+    /// ```
+    #[clippy::version = "1.66.0"]
+    pub MANUAL_FILTER,
+    complexity,
+    "reimplentation of `filter`"
+}
+
 #[derive(Default)]
 pub struct Matches {
     msrv: Option<RustcVersion>,
@@ -939,6 +969,7 @@ impl_lint_pass!(Matches => [
     SIGNIFICANT_DROP_IN_SCRUTINEE,
     TRY_ERR,
     MANUAL_MAP,
+    MANUAL_FILTER,
 ]);
 
 impl<'tcx> LateLintPass<'tcx> for Matches {
@@ -988,6 +1019,7 @@ impl<'tcx> LateLintPass<'tcx> for Matches {
                     if !in_constant(cx, expr.hir_id) {
                         manual_unwrap_or::check(cx, expr, ex, arms);
                         manual_map::check_match(cx, expr, ex, arms);
+                        manual_filter::check_match(cx, ex, arms, expr);
                     }
 
                     if self.infallible_destructuring_match_linted {
@@ -1014,6 +1046,14 @@ impl<'tcx> LateLintPass<'tcx> for Matches {
                     }
                     if !in_constant(cx, expr.hir_id) {
                         manual_map::check_if_let(cx, expr, if_let.let_pat, if_let.let_expr, if_let.if_then, else_expr);
+                        manual_filter::check_if_let(
+                            cx,
+                            expr,
+                            if_let.let_pat,
+                            if_let.let_expr,
+                            if_let.if_then,
+                            else_expr,
+                        );
                     }
                 }
                 redundant_pattern_match::check_if_let(
diff --git a/src/tools/clippy/clippy_lints/src/matches/single_match.rs b/src/tools/clippy/clippy_lints/src/matches/single_match.rs
index d496107ffd6b..e5a15b2e1a1d 100644
--- a/src/tools/clippy/clippy_lints/src/matches/single_match.rs
+++ b/src/tools/clippy/clippy_lints/src/matches/single_match.rs
@@ -1,14 +1,13 @@
 use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::source::{expr_block, snippet};
-use clippy_utils::ty::{implements_trait, match_type, peel_mid_ty_refs};
-use clippy_utils::{
-    is_lint_allowed, is_unit_expr, is_wild, paths, peel_blocks, peel_hir_pat_refs, peel_n_hir_expr_refs,
-};
+use clippy_utils::ty::{implements_trait, is_type_diagnostic_item, peel_mid_ty_refs};
+use clippy_utils::{is_lint_allowed, is_unit_expr, is_wild, peel_blocks, peel_hir_pat_refs, peel_n_hir_expr_refs};
 use core::cmp::max;
 use rustc_errors::Applicability;
 use rustc_hir::{Arm, BindingAnnotation, Block, Expr, ExprKind, Pat, PatKind};
 use rustc_lint::LateContext;
 use rustc_middle::ty::{self, Ty};
+use rustc_span::sym;
 
 use super::{MATCH_BOOL, SINGLE_MATCH, SINGLE_MATCH_ELSE};
 
@@ -156,10 +155,10 @@ fn pat_in_candidate_enum<'a>(cx: &LateContext<'a>, ty: Ty<'a>, pat: &Pat<'_>) ->
 /// Returns `true` if the given type is an enum we know won't be expanded in the future
 fn in_candidate_enum<'a>(cx: &LateContext<'a>, ty: Ty<'_>) -> bool {
     // list of candidate `Enum`s we know will never get any more members
-    let candidates = [&paths::COW, &paths::OPTION, &paths::RESULT];
+    let candidates = [sym::Cow, sym::Option, sym::Result];
 
     for candidate_ty in candidates {
-        if match_type(cx, ty, candidate_ty) {
+        if is_type_diagnostic_item(cx, ty, candidate_ty) {
             return true;
         }
     }
diff --git a/src/tools/clippy/clippy_lints/src/methods/bind_instead_of_map.rs b/src/tools/clippy/clippy_lints/src/methods/bind_instead_of_map.rs
index cc26b0f7fa82..4720a6e6888b 100644
--- a/src/tools/clippy/clippy_lints/src/methods/bind_instead_of_map.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/bind_instead_of_map.rs
@@ -41,7 +41,7 @@ pub(crate) trait BindInsteadOfMap {
     const GOOD_METHOD_NAME: &'static str;
 
     fn no_op_msg(cx: &LateContext<'_>) -> Option<String> {
-        let variant_id = cx.tcx.lang_items().require(Self::VARIANT_LANG_ITEM).ok()?;
+        let variant_id = cx.tcx.lang_items().get(Self::VARIANT_LANG_ITEM)?;
         let item_id = cx.tcx.parent(variant_id);
         Some(format!(
             "using `{}.{}({})`, which is a no-op",
@@ -52,7 +52,7 @@ pub(crate) trait BindInsteadOfMap {
     }
 
     fn lint_msg(cx: &LateContext<'_>) -> Option<String> {
-        let variant_id = cx.tcx.lang_items().require(Self::VARIANT_LANG_ITEM).ok()?;
+        let variant_id = cx.tcx.lang_items().get(Self::VARIANT_LANG_ITEM)?;
         let item_id = cx.tcx.parent(variant_id);
         Some(format!(
             "using `{}.{}(|x| {}(y))`, which is more succinctly expressed as `{}(|x| y)`",
@@ -144,7 +144,7 @@ pub(crate) trait BindInsteadOfMap {
     fn check(cx: &LateContext<'_>, expr: &hir::Expr<'_>, recv: &hir::Expr<'_>, arg: &hir::Expr<'_>) -> bool {
         if_chain! {
             if let Some(adt) = cx.typeck_results().expr_ty(recv).ty_adt_def();
-            if let Ok(vid) = cx.tcx.lang_items().require(Self::VARIANT_LANG_ITEM);
+            if let Some(vid) = cx.tcx.lang_items().get(Self::VARIANT_LANG_ITEM);
             if adt.did() == cx.tcx.parent(vid);
             then {} else { return false; }
         }
@@ -181,7 +181,7 @@ pub(crate) trait BindInsteadOfMap {
 
     fn is_variant(cx: &LateContext<'_>, res: Res) -> bool {
         if let Res::Def(DefKind::Ctor(CtorOf::Variant, CtorKind::Fn), id) = res {
-            if let Ok(variant_id) = cx.tcx.lang_items().require(Self::VARIANT_LANG_ITEM) {
+            if let Some(variant_id) = cx.tcx.lang_items().get(Self::VARIANT_LANG_ITEM) {
                 return cx.tcx.parent(id) == variant_id;
             }
         }
diff --git a/src/tools/clippy/clippy_lints/src/methods/into_iter_on_ref.rs b/src/tools/clippy/clippy_lints/src/methods/into_iter_on_ref.rs
index be56b63506a4..8adf9e370592 100644
--- a/src/tools/clippy/clippy_lints/src/methods/into_iter_on_ref.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/into_iter_on_ref.rs
@@ -42,9 +42,8 @@ pub(super) fn check(
 
 fn ty_has_iter_method(cx: &LateContext<'_>, self_ref_ty: Ty<'_>) -> Option<(Symbol, &'static str)> {
     has_iter_method(cx, self_ref_ty).map(|ty_name| {
-        let mutbl = match self_ref_ty.kind() {
-            ty::Ref(_, _, mutbl) => mutbl,
-            _ => unreachable!(),
+        let ty::Ref(_, _, mutbl) = self_ref_ty.kind() else {
+            unreachable!()
         };
         let method_name = match mutbl {
             hir::Mutability::Not => "iter",
diff --git a/src/tools/clippy/clippy_lints/src/methods/manual_saturating_arithmetic.rs b/src/tools/clippy/clippy_lints/src/methods/manual_saturating_arithmetic.rs
index ec694cf6882e..b80541b86479 100644
--- a/src/tools/clippy/clippy_lints/src/methods/manual_saturating_arithmetic.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/manual_saturating_arithmetic.rs
@@ -21,11 +21,7 @@ pub fn check(
         return;
     }
 
-    let mm = if let Some(mm) = is_min_or_max(cx, unwrap_arg) {
-        mm
-    } else {
-        return;
-    };
+    let Some(mm) = is_min_or_max(cx, unwrap_arg) else { return };
 
     if ty.is_signed() {
         use self::{
@@ -33,9 +29,7 @@ pub fn check(
             Sign::{Neg, Pos},
         };
 
-        let sign = if let Some(sign) = lit_sign(arith_rhs) {
-            sign
-        } else {
+        let Some(sign) = lit_sign(arith_rhs) else {
             return;
         };
 
diff --git a/src/tools/clippy/clippy_lints/src/methods/mod.rs b/src/tools/clippy/clippy_lints/src/methods/mod.rs
index cfcf9596c50d..8a76ba0b064b 100644
--- a/src/tools/clippy/clippy_lints/src/methods/mod.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/mod.rs
@@ -102,9 +102,7 @@ use bind_instead_of_map::BindInsteadOfMap;
 use clippy_utils::consts::{constant, Constant};
 use clippy_utils::diagnostics::{span_lint, span_lint_and_help};
 use clippy_utils::ty::{contains_adt_constructor, implements_trait, is_copy, is_type_diagnostic_item};
-use clippy_utils::{
-    contains_return, get_trait_def_id, is_trait_method, iter_input_pats, meets_msrv, msrvs, paths, return_ty,
-};
+use clippy_utils::{contains_return, is_trait_method, iter_input_pats, meets_msrv, msrvs, return_ty};
 use if_chain::if_chain;
 use rustc_hir as hir;
 use rustc_hir::def::Res;
@@ -3252,15 +3250,15 @@ impl<'tcx> LateLintPass<'tcx> for Methods {
         let name = impl_item.ident.name.as_str();
         let parent = cx.tcx.hir().get_parent_item(impl_item.hir_id()).def_id;
         let item = cx.tcx.hir().expect_item(parent);
-        let self_ty = cx.tcx.type_of(item.def_id);
+        let self_ty = cx.tcx.type_of(item.owner_id);
 
         let implements_trait = matches!(item.kind, hir::ItemKind::Impl(hir::Impl { of_trait: Some(_), .. }));
         if let hir::ImplItemKind::Fn(ref sig, id) = impl_item.kind {
-            let method_sig = cx.tcx.fn_sig(impl_item.def_id);
+            let method_sig = cx.tcx.fn_sig(impl_item.owner_id);
             let method_sig = cx.tcx.erase_late_bound_regions(method_sig);
             let first_arg_ty_opt = method_sig.inputs().iter().next().copied();
             // if this impl block implements a trait, lint in trait definition instead
-            if !implements_trait && cx.access_levels.is_exported(impl_item.def_id.def_id) {
+            if !implements_trait && cx.effective_visibilities.is_exported(impl_item.owner_id.def_id) {
                 // check missing trait implementations
                 for method_config in &TRAIT_METHODS {
                     if name == method_config.method_name
@@ -3294,7 +3292,7 @@ impl<'tcx> LateLintPass<'tcx> for Methods {
 
             if sig.decl.implicit_self.has_implicit_self()
                     && !(self.avoid_breaking_exported_api
-                    && cx.access_levels.is_exported(impl_item.def_id.def_id))
+                    && cx.effective_visibilities.is_exported(impl_item.owner_id.def_id))
                     && let Some(first_arg) = iter_input_pats(sig.decl, cx.tcx.hir().body(id)).next()
                     && let Some(first_arg_ty) = first_arg_ty_opt
                 {
@@ -3372,7 +3370,9 @@ impl<'tcx> LateLintPass<'tcx> for Methods {
             then {
                 let first_arg_span = first_arg_ty.span;
                 let first_arg_ty = hir_ty_to_ty(cx.tcx, first_arg_ty);
-                let self_ty = TraitRef::identity(cx.tcx, item.def_id.to_def_id()).self_ty().skip_binder();
+                let self_ty = TraitRef::identity(cx.tcx, item.owner_id.to_def_id())
+                    .self_ty()
+                    .skip_binder();
                 wrong_self_convention::check(
                     cx,
                     item.ident.name.as_str(),
@@ -3380,7 +3380,7 @@ impl<'tcx> LateLintPass<'tcx> for Methods {
                     first_arg_ty,
                     first_arg_span,
                     false,
-                    true
+                    true,
                 );
             }
         }
@@ -3389,7 +3389,9 @@ impl<'tcx> LateLintPass<'tcx> for Methods {
             if item.ident.name == sym::new;
             if let TraitItemKind::Fn(_, _) = item.kind;
             let ret_ty = return_ty(cx, item.hir_id());
-            let self_ty = TraitRef::identity(cx.tcx, item.def_id.to_def_id()).self_ty().skip_binder();
+            let self_ty = TraitRef::identity(cx.tcx, item.owner_id.to_def_id())
+                .self_ty()
+                .skip_binder();
             if !ret_ty.contains(self_ty);
 
             then {
@@ -3846,14 +3848,13 @@ impl SelfKind {
                 return m == mutability && t == parent_ty;
             }
 
-            let trait_path = match mutability {
-                hir::Mutability::Not => &paths::ASREF_TRAIT,
-                hir::Mutability::Mut => &paths::ASMUT_TRAIT,
+            let trait_sym = match mutability {
+                hir::Mutability::Not => sym::AsRef,
+                hir::Mutability::Mut => sym::AsMut,
             };
 
-            let trait_def_id = match get_trait_def_id(cx, trait_path) {
-                Some(did) => did,
-                None => return false,
+            let Some(trait_def_id) = cx.tcx.get_diagnostic_item(trait_sym) else {
+                return false
             };
             implements_trait(cx, ty, trait_def_id, &[parent_ty.into()])
         }
diff --git a/src/tools/clippy/clippy_lints/src/methods/option_as_ref_deref.rs b/src/tools/clippy/clippy_lints/src/methods/option_as_ref_deref.rs
index 6fb92d1c663c..742483e6b2e5 100644
--- a/src/tools/clippy/clippy_lints/src/methods/option_as_ref_deref.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/option_as_ref_deref.rs
@@ -32,8 +32,7 @@ pub(super) fn check<'tcx>(
         return;
     }
 
-    let deref_aliases: [&[&str]; 9] = [
-        &paths::DEREF_TRAIT_METHOD,
+    let deref_aliases: [&[&str]; 8] = [
         &paths::DEREF_MUT_TRAIT_METHOD,
         &paths::CSTRING_AS_C_STR,
         &paths::OS_STRING_AS_OS_STR,
@@ -45,12 +44,14 @@ pub(super) fn check<'tcx>(
     ];
 
     let is_deref = match map_arg.kind {
-        hir::ExprKind::Path(ref expr_qpath) => cx
-            .qpath_res(expr_qpath, map_arg.hir_id)
-            .opt_def_id()
-            .map_or(false, |fun_def_id| {
-                deref_aliases.iter().any(|path| match_def_path(cx, fun_def_id, path))
-            }),
+        hir::ExprKind::Path(ref expr_qpath) => {
+            cx.qpath_res(expr_qpath, map_arg.hir_id)
+                .opt_def_id()
+                .map_or(false, |fun_def_id| {
+                    cx.tcx.is_diagnostic_item(sym::deref_method, fun_def_id)
+                        || deref_aliases.iter().any(|path| match_def_path(cx, fun_def_id, path))
+                })
+        },
         hir::ExprKind::Closure(&hir::Closure { body, .. }) => {
             let closure_body = cx.tcx.hir().body(body);
             let closure_expr = peel_blocks(closure_body.value);
@@ -68,7 +69,8 @@ pub(super) fn check<'tcx>(
                         if let [ty::adjustment::Adjust::Deref(None), ty::adjustment::Adjust::Borrow(_)] = *adj;
                         then {
                             let method_did = cx.typeck_results().type_dependent_def_id(closure_expr.hir_id).unwrap();
-                            deref_aliases.iter().any(|path| match_def_path(cx, method_did, path))
+                            cx.tcx.is_diagnostic_item(sym::deref_method, method_did)
+                                || deref_aliases.iter().any(|path| match_def_path(cx, method_did, path))
                         } else {
                             false
                         }
diff --git a/src/tools/clippy/clippy_lints/src/methods/or_fun_call.rs b/src/tools/clippy/clippy_lints/src/methods/or_fun_call.rs
index 6a35024d0361..991d3dd538bf 100644
--- a/src/tools/clippy/clippy_lints/src/methods/or_fun_call.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/or_fun_call.rs
@@ -1,14 +1,14 @@
 use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::eager_or_lazy::switch_to_lazy_eval;
 use clippy_utils::source::{snippet, snippet_with_macro_callsite};
-use clippy_utils::ty::{implements_trait, match_type};
-use clippy_utils::{contains_return, is_trait_item, last_path_segment, paths};
+use clippy_utils::ty::{implements_trait, is_type_diagnostic_item};
+use clippy_utils::{contains_return, is_trait_item, last_path_segment};
 use if_chain::if_chain;
 use rustc_errors::Applicability;
 use rustc_hir as hir;
 use rustc_lint::LateContext;
 use rustc_span::source_map::Span;
-use rustc_span::symbol::{kw, sym};
+use rustc_span::symbol::{kw, sym, Symbol};
 use std::borrow::Cow;
 
 use super::OR_FUN_CALL;
@@ -88,11 +88,11 @@ pub(super) fn check<'tcx>(
         fun_span: Option<Span>,
     ) {
         // (path, fn_has_argument, methods, suffix)
-        const KNOW_TYPES: [(&[&str], bool, &[&str], &str); 4] = [
-            (&paths::BTREEMAP_ENTRY, false, &["or_insert"], "with"),
-            (&paths::HASHMAP_ENTRY, false, &["or_insert"], "with"),
-            (&paths::OPTION, false, &["map_or", "ok_or", "or", "unwrap_or"], "else"),
-            (&paths::RESULT, true, &["or", "unwrap_or"], "else"),
+        const KNOW_TYPES: [(Symbol, bool, &[&str], &str); 4] = [
+            (sym::BTreeEntry, false, &["or_insert"], "with"),
+            (sym::HashMapEntry, false, &["or_insert"], "with"),
+            (sym::Option, false, &["map_or", "ok_or", "or", "unwrap_or"], "else"),
+            (sym::Result, true, &["or", "unwrap_or"], "else"),
         ];
 
         if_chain! {
@@ -104,7 +104,7 @@ pub(super) fn check<'tcx>(
             let self_ty = cx.typeck_results().expr_ty(self_expr);
 
             if let Some(&(_, fn_has_arguments, poss, suffix)) =
-                KNOW_TYPES.iter().find(|&&i| match_type(cx, self_ty, i.0));
+                KNOW_TYPES.iter().find(|&&i| is_type_diagnostic_item(cx, self_ty, i.0));
 
             if poss.contains(&name);
 
@@ -121,10 +121,9 @@ pub(super) fn check<'tcx>(
                             macro_expanded_snipped = snippet(cx, snippet_span, "..");
                             match macro_expanded_snipped.strip_prefix("$crate::vec::") {
                                 Some(stripped) => Cow::from(stripped),
-                                None => macro_expanded_snipped
+                                None => macro_expanded_snipped,
                             }
-                        }
-                        else {
+                        } else {
                             not_macro_argument_snippet
                         }
                     };
diff --git a/src/tools/clippy/clippy_lints/src/methods/str_splitn.rs b/src/tools/clippy/clippy_lints/src/methods/str_splitn.rs
index ae3594bd36c3..1acac59144ce 100644
--- a/src/tools/clippy/clippy_lints/src/methods/str_splitn.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/str_splitn.rs
@@ -289,9 +289,7 @@ fn parse_iter_usage<'tcx>(
 ) -> Option<IterUsage> {
     let (kind, span) = match iter.next() {
         Some((_, Node::Expr(e))) if e.span.ctxt() == ctxt => {
-            let (name, args) = if let ExprKind::MethodCall(name, _, [args @ ..], _) = e.kind {
-                (name, args)
-            } else {
+            let ExprKind::MethodCall(name, _, [args @ ..], _) = e.kind else {
                 return None;
             };
             let did = cx.typeck_results().type_dependent_def_id(e.hir_id)?;
diff --git a/src/tools/clippy/clippy_lints/src/methods/unnecessary_iter_cloned.rs b/src/tools/clippy/clippy_lints/src/methods/unnecessary_iter_cloned.rs
index 1966a85f7a73..4eb579af7a12 100644
--- a/src/tools/clippy/clippy_lints/src/methods/unnecessary_iter_cloned.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/unnecessary_iter_cloned.rs
@@ -5,7 +5,7 @@ use clippy_utils::source::snippet_opt;
 use clippy_utils::ty::{get_associated_type, get_iterator_item_ty, implements_trait};
 use clippy_utils::{fn_def_id, get_parent_expr};
 use rustc_errors::Applicability;
-use rustc_hir::{def_id::DefId, Expr, ExprKind, LangItem};
+use rustc_hir::{def_id::DefId, Expr, ExprKind};
 use rustc_lint::LateContext;
 use rustc_span::{sym, Symbol};
 
@@ -100,5 +100,5 @@ pub fn check_for_loop_iter(
 
 /// Returns true if the named method is `IntoIterator::into_iter`.
 pub fn is_into_iter(cx: &LateContext<'_>, callee_def_id: DefId) -> bool {
-    cx.tcx.lang_items().require(LangItem::IntoIterIntoIter) == Ok(callee_def_id)
+    Some(callee_def_id) == cx.tcx.lang_items().into_iter_fn()
 }
diff --git a/src/tools/clippy/clippy_lints/src/methods/unnecessary_to_owned.rs b/src/tools/clippy/clippy_lints/src/methods/unnecessary_to_owned.rs
index 5cf88bfc8880..642a64ae77b6 100644
--- a/src/tools/clippy/clippy_lints/src/methods/unnecessary_to_owned.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/unnecessary_to_owned.rs
@@ -7,7 +7,7 @@ use clippy_utils::visitors::find_all_ret_expressions;
 use clippy_utils::{fn_def_id, get_parent_expr, is_diag_item_method, is_diag_trait_item, return_ty};
 use clippy_utils::{meets_msrv, msrvs};
 use rustc_errors::Applicability;
-use rustc_hir::{def_id::DefId, BorrowKind, Expr, ExprKind, ItemKind, LangItem, Node};
+use rustc_hir::{def_id::DefId, BorrowKind, Expr, ExprKind, ItemKind, Node};
 use rustc_hir_typeck::{FnCtxt, Inherited};
 use rustc_infer::infer::TyCtxtInferExt;
 use rustc_lint::LateContext;
@@ -363,7 +363,7 @@ fn can_change_type<'a>(cx: &LateContext<'a>, mut expr: &'a Expr<'a>, mut ty: Ty<
                 && let output_ty = return_ty(cx, item.hir_id())
                 && let local_def_id = cx.tcx.hir().local_def_id(item.hir_id())
                 && Inherited::build(cx.tcx, local_def_id).enter(|inherited| {
-                    let fn_ctxt = FnCtxt::new(&inherited, cx.param_env, item.hir_id());
+                    let fn_ctxt = FnCtxt::new(inherited, cx.param_env, item.hir_id());
                     fn_ctxt.can_coerce(ty, output_ty)
                 }) {
                     if has_lifetime(output_ty) && has_lifetime(ty) {
@@ -378,7 +378,7 @@ fn can_change_type<'a>(cx: &LateContext<'a>, mut expr: &'a Expr<'a>, mut ty: Ty<
             Node::Expr(parent_expr) => {
                 if let Some((callee_def_id, call_substs, recv, call_args)) = get_callee_substs_and_args(cx, parent_expr)
                 {
-                    if cx.tcx.lang_items().require(LangItem::IntoFutureIntoFuture) == Ok(callee_def_id) {
+                    if Some(callee_def_id) == cx.tcx.lang_items().into_future_fn() {
                         return false;
                     }
 
diff --git a/src/tools/clippy/clippy_lints/src/misc_early/literal_suffix.rs b/src/tools/clippy/clippy_lints/src/misc_early/literal_suffix.rs
index 62c6ca32d31a..27e7f8505eb5 100644
--- a/src/tools/clippy/clippy_lints/src/misc_early/literal_suffix.rs
+++ b/src/tools/clippy/clippy_lints/src/misc_early/literal_suffix.rs
@@ -6,9 +6,7 @@ use rustc_lint::EarlyContext;
 use super::{SEPARATED_LITERAL_SUFFIX, UNSEPARATED_LITERAL_SUFFIX};
 
 pub(super) fn check(cx: &EarlyContext<'_>, lit: &Lit, lit_snip: &str, suffix: &str, sugg_type: &str) {
-    let maybe_last_sep_idx = if let Some(val) = lit_snip.len().checked_sub(suffix.len() + 1) {
-        val
-    } else {
+    let Some(maybe_last_sep_idx) = lit_snip.len().checked_sub(suffix.len() + 1) else {
         return; // It's useless so shouldn't lint.
     };
     // Do not lint when literal is unsuffixed.
diff --git a/src/tools/clippy/clippy_lints/src/misc_early/mixed_case_hex_literals.rs b/src/tools/clippy/clippy_lints/src/misc_early/mixed_case_hex_literals.rs
index 80e242131007..263ee1e945a2 100644
--- a/src/tools/clippy/clippy_lints/src/misc_early/mixed_case_hex_literals.rs
+++ b/src/tools/clippy/clippy_lints/src/misc_early/mixed_case_hex_literals.rs
@@ -5,9 +5,7 @@ use rustc_lint::EarlyContext;
 use super::MIXED_CASE_HEX_LITERALS;
 
 pub(super) fn check(cx: &EarlyContext<'_>, lit: &Lit, suffix: &str, lit_snip: &str) {
-    let maybe_last_sep_idx = if let Some(val) = lit_snip.len().checked_sub(suffix.len() + 1) {
-        val
-    } else {
+    let Some(maybe_last_sep_idx) = lit_snip.len().checked_sub(suffix.len() + 1) else {
         return; // It's useless so shouldn't lint.
     };
     if maybe_last_sep_idx <= 2 {
diff --git a/src/tools/clippy/clippy_lints/src/misc_early/zero_prefixed_literal.rs b/src/tools/clippy/clippy_lints/src/misc_early/zero_prefixed_literal.rs
index 4963bba82f2d..9ead43ea4a47 100644
--- a/src/tools/clippy/clippy_lints/src/misc_early/zero_prefixed_literal.rs
+++ b/src/tools/clippy/clippy_lints/src/misc_early/zero_prefixed_literal.rs
@@ -6,6 +6,7 @@ use rustc_lint::EarlyContext;
 use super::ZERO_PREFIXED_LITERAL;
 
 pub(super) fn check(cx: &EarlyContext<'_>, lit: &Lit, lit_snip: &str) {
+    let trimmed_lit_snip = lit_snip.trim_start_matches(|c| c == '_' || c == '0');
     span_lint_and_then(
         cx,
         ZERO_PREFIXED_LITERAL,
@@ -15,15 +16,18 @@ pub(super) fn check(cx: &EarlyContext<'_>, lit: &Lit, lit_snip: &str) {
             diag.span_suggestion(
                 lit.span,
                 "if you mean to use a decimal constant, remove the `0` to avoid confusion",
-                lit_snip.trim_start_matches(|c| c == '_' || c == '0').to_string(),
-                Applicability::MaybeIncorrect,
-            );
-            diag.span_suggestion(
-                lit.span,
-                "if you mean to use an octal constant, use `0o`",
-                format!("0o{}", lit_snip.trim_start_matches(|c| c == '_' || c == '0')),
+                trimmed_lit_snip.to_string(),
                 Applicability::MaybeIncorrect,
             );
+            // do not advise to use octal form if the literal cannot be expressed in base 8.
+            if !lit_snip.contains(|c| c == '8' || c == '9') {
+                diag.span_suggestion(
+                    lit.span,
+                    "if you mean to use an octal constant, use `0o`",
+                    format!("0o{trimmed_lit_snip}"),
+                    Applicability::MaybeIncorrect,
+                );
+            }
         },
     );
 }
diff --git a/src/tools/clippy/clippy_lints/src/mismatching_type_param_order.rs b/src/tools/clippy/clippy_lints/src/mismatching_type_param_order.rs
index 6dd76a6531e4..9de4b56b77b5 100644
--- a/src/tools/clippy/clippy_lints/src/mismatching_type_param_order.rs
+++ b/src/tools/clippy/clippy_lints/src/mismatching_type_param_order.rs
@@ -70,9 +70,8 @@ impl<'tcx> LateLintPass<'tcx> for TypeParamMismatch {
 
                 // find the type that the Impl is for
                 // only lint on struct/enum/union for now
-                let defid = match path.res {
-                    Res::Def(DefKind::Struct | DefKind::Enum | DefKind::Union, defid) => defid,
-                    _ => return,
+                let Res::Def(DefKind::Struct | DefKind::Enum | DefKind::Union, defid) = path.res else {
+                    return
                 };
 
                 // get the names of the generic parameters in the type
diff --git a/src/tools/clippy/clippy_lints/src/missing_doc.rs b/src/tools/clippy/clippy_lints/src/missing_doc.rs
index b3f1553cfea9..2a63681db60e 100644
--- a/src/tools/clippy/clippy_lints/src/missing_doc.rs
+++ b/src/tools/clippy/clippy_lints/src/missing_doc.rs
@@ -131,7 +131,7 @@ impl<'tcx> LateLintPass<'tcx> for MissingDoc {
             hir::ItemKind::Fn(..) => {
                 // ignore main()
                 if it.ident.name == sym::main {
-                    let at_root = cx.tcx.local_parent(it.def_id.def_id) == CRATE_DEF_ID;
+                    let at_root = cx.tcx.local_parent(it.owner_id.def_id) == CRATE_DEF_ID;
                     if at_root {
                         return;
                     }
@@ -155,7 +155,7 @@ impl<'tcx> LateLintPass<'tcx> for MissingDoc {
             | hir::ItemKind::Use(..) => return,
         };
 
-        let (article, desc) = cx.tcx.article_and_description(it.def_id.to_def_id());
+        let (article, desc) = cx.tcx.article_and_description(it.owner_id.to_def_id());
 
         let attrs = cx.tcx.hir().attrs(it.hir_id());
         if !is_from_proc_macro(cx, it) {
@@ -164,7 +164,7 @@ impl<'tcx> LateLintPass<'tcx> for MissingDoc {
     }
 
     fn check_trait_item(&mut self, cx: &LateContext<'tcx>, trait_item: &'tcx hir::TraitItem<'_>) {
-        let (article, desc) = cx.tcx.article_and_description(trait_item.def_id.to_def_id());
+        let (article, desc) = cx.tcx.article_and_description(trait_item.owner_id.to_def_id());
 
         let attrs = cx.tcx.hir().attrs(trait_item.hir_id());
         if !is_from_proc_macro(cx, trait_item) {
@@ -174,7 +174,7 @@ impl<'tcx> LateLintPass<'tcx> for MissingDoc {
 
     fn check_impl_item(&mut self, cx: &LateContext<'tcx>, impl_item: &'tcx hir::ImplItem<'_>) {
         // If the method is an impl for a trait, don't doc.
-        if let Some(cid) = cx.tcx.associated_item(impl_item.def_id).impl_container(cx.tcx) {
+        if let Some(cid) = cx.tcx.associated_item(impl_item.owner_id).impl_container(cx.tcx) {
             if cx.tcx.impl_trait_ref(cid).is_some() {
                 return;
             }
@@ -182,7 +182,7 @@ impl<'tcx> LateLintPass<'tcx> for MissingDoc {
             return;
         }
 
-        let (article, desc) = cx.tcx.article_and_description(impl_item.def_id.to_def_id());
+        let (article, desc) = cx.tcx.article_and_description(impl_item.owner_id.to_def_id());
         let attrs = cx.tcx.hir().attrs(impl_item.hir_id());
         if !is_from_proc_macro(cx, impl_item) {
             self.check_missing_docs_attrs(cx, attrs, impl_item.span, article, desc);
diff --git a/src/tools/clippy/clippy_lints/src/missing_inline.rs b/src/tools/clippy/clippy_lints/src/missing_inline.rs
index 01c87f058ade..758ce47cf114 100644
--- a/src/tools/clippy/clippy_lints/src/missing_inline.rs
+++ b/src/tools/clippy/clippy_lints/src/missing_inline.rs
@@ -88,7 +88,7 @@ impl<'tcx> LateLintPass<'tcx> for MissingInline {
             return;
         }
 
-        if !cx.access_levels.is_exported(it.def_id.def_id) {
+        if !cx.effective_visibilities.is_exported(it.owner_id.def_id) {
             return;
         }
         match it.kind {
@@ -105,7 +105,7 @@ impl<'tcx> LateLintPass<'tcx> for MissingInline {
                     match tit_.kind {
                         hir::TraitItemKind::Const(..) | hir::TraitItemKind::Type(..) => {},
                         hir::TraitItemKind::Fn(..) => {
-                            if cx.tcx.impl_defaultness(tit.id.def_id).has_value() {
+                            if cx.tcx.impl_defaultness(tit.id.owner_id).has_value() {
                                 // trait method with default body needs inline in case
                                 // an impl is not provided
                                 let desc = "a default trait method";
@@ -142,7 +142,7 @@ impl<'tcx> LateLintPass<'tcx> for MissingInline {
         }
 
         // If the item being implemented is not exported, then we don't need #[inline]
-        if !cx.access_levels.is_exported(impl_item.def_id.def_id) {
+        if !cx.effective_visibilities.is_exported(impl_item.owner_id.def_id) {
             return;
         }
 
@@ -151,7 +151,7 @@ impl<'tcx> LateLintPass<'tcx> for MissingInline {
             hir::ImplItemKind::Const(..) | hir::ImplItemKind::Type(_) => return,
         };
 
-        let assoc_item = cx.tcx.associated_item(impl_item.def_id);
+        let assoc_item = cx.tcx.associated_item(impl_item.owner_id);
         let container_id = assoc_item.container_id(cx.tcx);
         let trait_def_id = match assoc_item.container {
             TraitContainer => Some(container_id),
@@ -159,7 +159,7 @@ impl<'tcx> LateLintPass<'tcx> for MissingInline {
         };
 
         if let Some(trait_def_id) = trait_def_id {
-            if trait_def_id.is_local() && !cx.access_levels.is_exported(impl_item.def_id.def_id) {
+            if trait_def_id.is_local() && !cx.effective_visibilities.is_exported(impl_item.owner_id.def_id) {
                 // If a trait is being implemented for an item, and the
                 // trait is not exported, we don't need #[inline]
                 return;
diff --git a/src/tools/clippy/clippy_lints/src/missing_trait_methods.rs b/src/tools/clippy/clippy_lints/src/missing_trait_methods.rs
new file mode 100644
index 000000000000..68af8a672f6a
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/missing_trait_methods.rs
@@ -0,0 +1,98 @@
+use clippy_utils::diagnostics::span_lint_and_help;
+use clippy_utils::is_lint_allowed;
+use clippy_utils::macros::span_is_local;
+use rustc_hir::def_id::DefIdMap;
+use rustc_hir::{Impl, Item, ItemKind};
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_middle::ty::AssocItem;
+use rustc_session::{declare_lint_pass, declare_tool_lint};
+
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks if a provided method is used implicitly by a trait
+    /// implementation. A usage example would be a wrapper where every method
+    /// should perform some operation before delegating to the inner type's
+    /// implemenation.
+    ///
+    /// This lint should typically be enabled on a specific trait `impl` item
+    /// rather than globally.
+    ///
+    /// ### Why is this bad?
+    /// Indicates that a method is missing.
+    ///
+    /// ### Example
+    /// ```rust
+    /// trait Trait {
+    ///     fn required();
+    ///
+    ///     fn provided() {}
+    /// }
+    ///
+    /// # struct Type;
+    /// #[warn(clippy::missing_trait_methods)]
+    /// impl Trait for Type {
+    ///     fn required() { /* ... */ }
+    /// }
+    /// ```
+    /// Use instead:
+    /// ```rust
+    /// trait Trait {
+    ///     fn required();
+    ///
+    ///     fn provided() {}
+    /// }
+    ///
+    /// # struct Type;
+    /// #[warn(clippy::missing_trait_methods)]
+    /// impl Trait for Type {
+    ///     fn required() { /* ... */ }
+    ///
+    ///     fn provided() { /* ... */ }
+    /// }
+    /// ```
+    #[clippy::version = "1.66.0"]
+    pub MISSING_TRAIT_METHODS,
+    restriction,
+    "trait implementation uses default provided method"
+}
+declare_lint_pass!(MissingTraitMethods => [MISSING_TRAIT_METHODS]);
+
+impl<'tcx> LateLintPass<'tcx> for MissingTraitMethods {
+    fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'tcx>) {
+        if !is_lint_allowed(cx, MISSING_TRAIT_METHODS, item.hir_id())
+            && span_is_local(item.span)
+            && let ItemKind::Impl(Impl {
+                items,
+                of_trait: Some(trait_ref),
+                ..
+            }) = item.kind
+            && let Some(trait_id) = trait_ref.trait_def_id()
+        {
+            let mut provided: DefIdMap<&AssocItem> = cx
+                .tcx
+                .provided_trait_methods(trait_id)
+                .map(|assoc| (assoc.def_id, assoc))
+                .collect();
+
+            for impl_item in *items {
+                if let Some(def_id) = impl_item.trait_item_def_id {
+                    provided.remove(&def_id);
+                }
+            }
+
+            for assoc in provided.values() {
+                let source_map = cx.tcx.sess.source_map();
+                let definition_span = source_map.guess_head_span(cx.tcx.def_span(assoc.def_id));
+
+                span_lint_and_help(
+                    cx,
+                    MISSING_TRAIT_METHODS,
+                    source_map.guess_head_span(item.span),
+                    &format!("missing trait method provided by default: `{}`", assoc.name),
+                    Some(definition_span),
+                    "implement the method",
+                );
+            }
+        }
+    }
+}
diff --git a/src/tools/clippy/clippy_lints/src/mixed_read_write_in_expression.rs b/src/tools/clippy/clippy_lints/src/mixed_read_write_in_expression.rs
index a2419c277e9c..6752976348f6 100644
--- a/src/tools/clippy/clippy_lints/src/mixed_read_write_in_expression.rs
+++ b/src/tools/clippy/clippy_lints/src/mixed_read_write_in_expression.rs
@@ -190,10 +190,7 @@ fn check_for_unsequenced_reads(vis: &mut ReadVisitor<'_, '_>) {
         if parent_id == cur_id {
             break;
         }
-        let parent_node = match map.find(parent_id) {
-            Some(parent) => parent,
-            None => break,
-        };
+        let Some(parent_node) = map.find(parent_id) else { break };
 
         let stop_early = match parent_node {
             Node::Expr(expr) => check_expr(vis, expr),
diff --git a/src/tools/clippy/clippy_lints/src/mut_key.rs b/src/tools/clippy/clippy_lints/src/mut_key.rs
index 25d6ca83a94b..4b62dcdffe2f 100644
--- a/src/tools/clippy/clippy_lints/src/mut_key.rs
+++ b/src/tools/clippy/clippy_lints/src/mut_key.rs
@@ -89,7 +89,7 @@ impl<'tcx> LateLintPass<'tcx> for MutableKeyType {
 
     fn check_impl_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx hir::ImplItem<'tcx>) {
         if let hir::ImplItemKind::Fn(ref sig, ..) = item.kind {
-            if trait_ref_of_method(cx, item.def_id.def_id).is_none() {
+            if trait_ref_of_method(cx, item.owner_id.def_id).is_none() {
                 check_sig(cx, item.hir_id(), sig.decl);
             }
         }
@@ -136,12 +136,14 @@ fn check_ty<'tcx>(cx: &LateContext<'tcx>, span: Span, ty: Ty<'tcx>) {
 /// [`Hash`] or [`Ord`].
 fn is_interior_mutable_type<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>, span: Span) -> bool {
     match *ty.kind() {
-        Ref(_, inner_ty, mutbl) => mutbl == hir::Mutability::Mut || is_interior_mutable_type(cx, inner_ty, span),
+        Ref(_, inner_ty, mutbl) => {
+            mutbl == hir::Mutability::Mut || is_interior_mutable_type(cx, inner_ty, span)
+        }
         Slice(inner_ty) => is_interior_mutable_type(cx, inner_ty, span),
         Array(inner_ty, size) => {
             size.try_eval_usize(cx.tcx, cx.param_env).map_or(true, |u| u != 0)
                 && is_interior_mutable_type(cx, inner_ty, span)
-        },
+        }
         Tuple(fields) => fields.iter().any(|ty| is_interior_mutable_type(cx, ty, span)),
         Adt(def, substs) => {
             // Special case for collections in `std` who's impl of `Hash` or `Ord` delegates to
@@ -167,9 +169,9 @@ fn is_interior_mutable_type<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>, span: Sp
             } else {
                 !ty.has_escaping_bound_vars()
                     && cx.tcx.layout_of(cx.param_env.and(ty)).is_ok()
-                    && !ty.is_freeze(cx.tcx.at(span), cx.param_env)
+                    && !ty.is_freeze(cx.tcx, cx.param_env)
             }
-        },
+        }
         _ => false,
     }
 }
diff --git a/src/tools/clippy/clippy_lints/src/needless_for_each.rs b/src/tools/clippy/clippy_lints/src/needless_for_each.rs
index 3233d87c0731..c3b633fd6a03 100644
--- a/src/tools/clippy/clippy_lints/src/needless_for_each.rs
+++ b/src/tools/clippy/clippy_lints/src/needless_for_each.rs
@@ -49,9 +49,8 @@ declare_lint_pass!(NeedlessForEach => [NEEDLESS_FOR_EACH]);
 
 impl<'tcx> LateLintPass<'tcx> for NeedlessForEach {
     fn check_stmt(&mut self, cx: &LateContext<'tcx>, stmt: &'tcx Stmt<'_>) {
-        let expr = match stmt.kind {
-            StmtKind::Expr(expr) | StmtKind::Semi(expr) => expr,
-            _ => return,
+        let (StmtKind::Expr(expr) | StmtKind::Semi(expr)) = stmt.kind else {
+             return
         };
 
         if_chain! {
diff --git a/src/tools/clippy/clippy_lints/src/needless_pass_by_value.rs b/src/tools/clippy/clippy_lints/src/needless_pass_by_value.rs
index 9c949a28f44d..b2e9ce5c94d6 100644
--- a/src/tools/clippy/clippy_lints/src/needless_pass_by_value.rs
+++ b/src/tools/clippy/clippy_lints/src/needless_pass_by_value.rs
@@ -19,7 +19,7 @@ use rustc_middle::mir::FakeReadCause;
 use rustc_middle::ty::{self, TypeVisitable};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 use rustc_span::symbol::kw;
-use rustc_span::{sym, Span, DUMMY_SP};
+use rustc_span::{sym, Span};
 use rustc_target::spec::abi::Abi;
 use rustc_trait_selection::traits;
 use rustc_trait_selection::traits::misc::can_type_implement_copy;
@@ -184,7 +184,7 @@ impl<'tcx> LateLintPass<'tcx> for NeedlessPassByValue {
                 if !is_self(arg);
                 if !ty.is_mutable_ptr();
                 if !is_copy(cx, ty);
-                if ty.is_sized(cx.tcx.at(DUMMY_SP), cx.param_env);
+                if ty.is_sized(cx.tcx, cx.param_env);
                 if !allowed_traits.iter().any(|&t| implements_trait(cx, ty, t, &[]));
                 if !implements_borrow_trait;
                 if !all_borrowable_trait;
diff --git a/src/tools/clippy/clippy_lints/src/neg_cmp_op_on_partial_ord.rs b/src/tools/clippy/clippy_lints/src/neg_cmp_op_on_partial_ord.rs
index a7e0e35787cf..5c2b96f5b2ce 100644
--- a/src/tools/clippy/clippy_lints/src/neg_cmp_op_on_partial_ord.rs
+++ b/src/tools/clippy/clippy_lints/src/neg_cmp_op_on_partial_ord.rs
@@ -1,11 +1,11 @@
 use clippy_utils::diagnostics::span_lint;
 use clippy_utils::ty::implements_trait;
-use clippy_utils::{self, get_trait_def_id, paths};
 use if_chain::if_chain;
 use rustc_hir::{BinOpKind, Expr, ExprKind, UnOp};
 use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_middle::lint::in_external_macro;
 use rustc_session::{declare_lint_pass, declare_tool_lint};
+use rustc_span::sym;
 
 declare_clippy_lint! {
     /// ### What it does
@@ -47,18 +47,16 @@ declare_lint_pass!(NoNegCompOpForPartialOrd => [NEG_CMP_OP_ON_PARTIAL_ORD]);
 impl<'tcx> LateLintPass<'tcx> for NoNegCompOpForPartialOrd {
     fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
         if_chain! {
-
             if !in_external_macro(cx.sess(), expr.span);
             if let ExprKind::Unary(UnOp::Not, inner) = expr.kind;
             if let ExprKind::Binary(ref op, left, _) = inner.kind;
             if let BinOpKind::Le | BinOpKind::Ge | BinOpKind::Lt | BinOpKind::Gt = op.node;
 
             then {
-
                 let ty = cx.typeck_results().expr_ty(left);
 
                 let implements_ord = {
-                    if let Some(id) = get_trait_def_id(cx, &paths::ORD) {
+                    if let Some(id) = cx.tcx.get_diagnostic_item(sym::Ord) {
                         implements_trait(cx, ty, id, &[])
                     } else {
                         return;
@@ -81,7 +79,7 @@ impl<'tcx> LateLintPass<'tcx> for NoNegCompOpForPartialOrd {
                         "the use of negated comparison operators on partially ordered \
                         types produces code that is hard to read and refactor, please \
                         consider using the `partial_cmp` method instead, to make it \
-                        clear that the two values could be incomparable"
+                        clear that the two values could be incomparable",
                     );
                 }
             }
diff --git a/src/tools/clippy/clippy_lints/src/new_without_default.rs b/src/tools/clippy/clippy_lints/src/new_without_default.rs
index 6017117e1ecc..54a3c82b713d 100644
--- a/src/tools/clippy/clippy_lints/src/new_without_default.rs
+++ b/src/tools/clippy/clippy_lints/src/new_without_default.rs
@@ -84,7 +84,7 @@ impl<'tcx> LateLintPass<'tcx> for NewWithoutDefault {
                             // can't be implemented for unsafe new
                             return;
                         }
-                        if cx.tcx.is_doc_hidden(impl_item.def_id.def_id) {
+                        if cx.tcx.is_doc_hidden(impl_item.owner_id.def_id) {
                             // shouldn't be implemented when it is hidden in docs
                             return;
                         }
@@ -96,7 +96,7 @@ impl<'tcx> LateLintPass<'tcx> for NewWithoutDefault {
                         if_chain! {
                             if sig.decl.inputs.is_empty();
                             if name == sym::new;
-                            if cx.access_levels.is_reachable(impl_item.def_id.def_id);
+                            if cx.effective_visibilities.is_reachable(impl_item.owner_id.def_id);
                             let self_def_id = cx.tcx.hir().get_parent_item(id);
                             let self_ty = cx.tcx.type_of(self_def_id);
                             if self_ty == return_ty(cx, id);
diff --git a/src/tools/clippy/clippy_lints/src/non_copy_const.rs b/src/tools/clippy/clippy_lints/src/non_copy_const.rs
index 2c839d029c6f..2a3bd4ee6ce6 100644
--- a/src/tools/clippy/clippy_lints/src/non_copy_const.rs
+++ b/src/tools/clippy/clippy_lints/src/non_copy_const.rs
@@ -20,7 +20,7 @@ use rustc_middle::mir::interpret::{ConstValue, ErrorHandled};
 use rustc_middle::ty::adjustment::Adjust;
 use rustc_middle::ty::{self, Ty};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
-use rustc_span::{sym, InnerSpan, Span, DUMMY_SP};
+use rustc_span::{sym, InnerSpan, Span};
 
 // FIXME: this is a correctness problem but there's no suitable
 // warn-by-default category.
@@ -136,7 +136,7 @@ fn is_unfrozen<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>) -> bool {
     // since it works when a pointer indirection involves (`Cell<*const T>`).
     // Making up a `ParamEnv` where every generic params and assoc types are `Freeze`is another option;
     // but I'm not sure whether it's a decent way, if possible.
-    cx.tcx.layout_of(cx.param_env.and(ty)).is_ok() && !ty.is_freeze(cx.tcx.at(DUMMY_SP), cx.param_env)
+    cx.tcx.layout_of(cx.param_env.and(ty)).is_ok() && !ty.is_freeze(cx.tcx, cx.param_env)
 }
 
 fn is_value_unfrozen_raw<'tcx>(
@@ -303,7 +303,7 @@ impl<'tcx> LateLintPass<'tcx> for NonCopyConst {
                         if let Some(of_trait_def_id) = of_trait_ref.trait_def_id();
                         if let Some(of_assoc_item) = cx
                             .tcx
-                            .associated_item(impl_item.def_id)
+                            .associated_item(impl_item.owner_id)
                             .trait_item_def_id;
                         if cx
                             .tcx
@@ -357,9 +357,8 @@ impl<'tcx> LateLintPass<'tcx> for NonCopyConst {
             }
 
             // Make sure it is a const item.
-            let item_def_id = match cx.qpath_res(qpath, expr.hir_id) {
-                Res::Def(DefKind::Const | DefKind::AssocConst, did) => did,
-                _ => return,
+            let Res::Def(DefKind::Const | DefKind::AssocConst, item_def_id) = cx.qpath_res(qpath, expr.hir_id) else {
+                return
             };
 
             // Climb up to resolve any field access and explicit referencing.
diff --git a/src/tools/clippy/clippy_lints/src/non_octal_unix_permissions.rs b/src/tools/clippy/clippy_lints/src/non_octal_unix_permissions.rs
index 1a765b14892f..2ecb04874842 100644
--- a/src/tools/clippy/clippy_lints/src/non_octal_unix_permissions.rs
+++ b/src/tools/clippy/clippy_lints/src/non_octal_unix_permissions.rs
@@ -55,9 +55,8 @@ impl<'tcx> LateLintPass<'tcx> for NonOctalUnixPermissions {
                     if let ExprKind::Lit(_) = param.kind;
 
                     then {
-                        let snip = match snippet_opt(cx, param.span) {
-                            Some(s) => s,
-                            _ => return,
+                        let Some(snip) = snippet_opt(cx, param.span) else {
+                            return
                         };
 
                         if !snip.starts_with("0o") {
@@ -72,16 +71,10 @@ impl<'tcx> LateLintPass<'tcx> for NonOctalUnixPermissions {
                     if let Some(def_id) = cx.qpath_res(path, func.hir_id).opt_def_id();
                     if match_def_path(cx, def_id, &paths::PERMISSIONS_FROM_MODE);
                     if let ExprKind::Lit(_) = param.kind;
-
+                    if let Some(snip) = snippet_opt(cx, param.span);
+                    if !snip.starts_with("0o");
                     then {
-                        let snip = match snippet_opt(cx, param.span) {
-                            Some(s) => s,
-                            _ => return,
-                        };
-
-                        if !snip.starts_with("0o") {
-                            show_error(cx, param);
-                        }
+                        show_error(cx, param);
                     }
                 }
             },
diff --git a/src/tools/clippy/clippy_lints/src/non_send_fields_in_send_ty.rs b/src/tools/clippy/clippy_lints/src/non_send_fields_in_send_ty.rs
index ddef7352de88..714c0ff227bf 100644
--- a/src/tools/clippy/clippy_lints/src/non_send_fields_in_send_ty.rs
+++ b/src/tools/clippy/clippy_lints/src/non_send_fields_in_send_ty.rs
@@ -89,7 +89,7 @@ impl<'tcx> LateLintPass<'tcx> for NonSendFieldInSendTy {
             if let Some(trait_id) = trait_ref.trait_def_id();
             if send_trait == trait_id;
             if hir_impl.polarity == ImplPolarity::Positive;
-            if let Some(ty_trait_ref) = cx.tcx.impl_trait_ref(item.def_id);
+            if let Some(ty_trait_ref) = cx.tcx.impl_trait_ref(item.owner_id);
             if let self_ty = ty_trait_ref.self_ty();
             if let ty::Adt(adt_def, impl_trait_substs) = self_ty.kind();
             then {
diff --git a/src/tools/clippy/clippy_lints/src/nonstandard_macro_braces.rs b/src/tools/clippy/clippy_lints/src/nonstandard_macro_braces.rs
index 0ca0befc1351..6c909e5ed73e 100644
--- a/src/tools/clippy/clippy_lints/src/nonstandard_macro_braces.rs
+++ b/src/tools/clippy/clippy_lints/src/nonstandard_macro_braces.rs
@@ -266,7 +266,7 @@ impl<'de> Deserialize<'de> for MacroMatcher {
                         .iter()
                         .find(|b| b.0 == brace)
                         .map(|(o, c)| ((*o).to_owned(), (*c).to_owned()))
-                        .ok_or_else(|| de::Error::custom(&format!("expected one of `(`, `{{`, `[` found `{brace}`")))?,
+                        .ok_or_else(|| de::Error::custom(format!("expected one of `(`, `{{`, `[` found `{brace}`")))?,
                 })
             }
         }
diff --git a/src/tools/clippy/clippy_lints/src/only_used_in_recursion.rs b/src/tools/clippy/clippy_lints/src/only_used_in_recursion.rs
index d64a9cf71e17..7722a476d7b4 100644
--- a/src/tools/clippy/clippy_lints/src/only_used_in_recursion.rs
+++ b/src/tools/clippy/clippy_lints/src/only_used_in_recursion.rs
@@ -227,25 +227,25 @@ impl<'tcx> LateLintPass<'tcx> for OnlyUsedInRecursion {
         // `skip_params` is either `0` or `1` to skip the `self` parameter in trait functions.
         // It can't be renamed, and it can't be removed without removing it from multiple functions.
         let (fn_id, fn_kind, skip_params) = match get_parent_node(cx.tcx, body.value.hir_id) {
-            Some(Node::Item(i)) => (i.def_id.to_def_id(), FnKind::Fn, 0),
+            Some(Node::Item(i)) => (i.owner_id.to_def_id(), FnKind::Fn, 0),
             Some(Node::TraitItem(&TraitItem {
                 kind: TraitItemKind::Fn(ref sig, _),
-                def_id,
+                owner_id,
                 ..
             })) => (
-                def_id.to_def_id(),
+                owner_id.to_def_id(),
                 FnKind::TraitFn,
                 usize::from(sig.decl.implicit_self.has_implicit_self()),
             ),
             Some(Node::ImplItem(&ImplItem {
                 kind: ImplItemKind::Fn(ref sig, _),
-                def_id,
+                owner_id,
                 ..
             })) => {
                 #[allow(trivial_casts)]
-                if let Some(Node::Item(item)) = get_parent_node(cx.tcx, def_id.into())
-                    && let Some(trait_ref) = cx.tcx.impl_trait_ref(item.def_id)
-                    && let Some(trait_item_id) = cx.tcx.associated_item(def_id).trait_item_def_id
+                if let Some(Node::Item(item)) = get_parent_node(cx.tcx, owner_id.into())
+                    && let Some(trait_ref) = cx.tcx.impl_trait_ref(item.owner_id)
+                    && let Some(trait_item_id) = cx.tcx.associated_item(owner_id).trait_item_def_id
                 {
                     (
                         trait_item_id,
@@ -253,7 +253,7 @@ impl<'tcx> LateLintPass<'tcx> for OnlyUsedInRecursion {
                         usize::from(sig.decl.implicit_self.has_implicit_self()),
                     )
                 } else {
-                    (def_id.to_def_id(), FnKind::Fn, 0)
+                    (owner_id.to_def_id(), FnKind::Fn, 0)
                 }
             },
             _ => return,
diff --git a/src/tools/clippy/clippy_lints/src/operators/assign_op_pattern.rs b/src/tools/clippy/clippy_lints/src/operators/assign_op_pattern.rs
index ee9fd94064c0..9bbf385fb599 100644
--- a/src/tools/clippy/clippy_lints/src/operators/assign_op_pattern.rs
+++ b/src/tools/clippy/clippy_lints/src/operators/assign_op_pattern.rs
@@ -28,7 +28,7 @@ pub(super) fn check<'tcx>(
             let rty = cx.typeck_results().expr_ty(rhs);
             if_chain! {
                 if let Some((_, lang_item)) = binop_traits(op.node);
-                if let Ok(trait_id) = cx.tcx.lang_items().require(lang_item);
+                if let Some(trait_id) = cx.tcx.lang_items().get(lang_item);
                 let parent_fn = cx.tcx.hir().get_parent_item(e.hir_id).def_id;
                 if trait_ref_of_method(cx, parent_fn)
                     .map_or(true, |t| t.path.res.def_id() != trait_id);
diff --git a/src/tools/clippy/clippy_lints/src/operators/cmp_owned.rs b/src/tools/clippy/clippy_lints/src/operators/cmp_owned.rs
index c9c777f1bd8d..24aeb82a37f3 100644
--- a/src/tools/clippy/clippy_lints/src/operators/cmp_owned.rs
+++ b/src/tools/clippy/clippy_lints/src/operators/cmp_owned.rs
@@ -1,7 +1,7 @@
 use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::source::snippet;
 use clippy_utils::ty::{implements_trait, is_copy};
-use clippy_utils::{match_any_def_paths, path_def_id, paths};
+use clippy_utils::{match_def_path, path_def_id, paths};
 use rustc_errors::Applicability;
 use rustc_hir::{BinOpKind, Expr, ExprKind, UnOp};
 use rustc_lint::LateContext;
@@ -49,13 +49,15 @@ fn check_op(cx: &LateContext<'_>, expr: &Expr<'_>, other: &Expr<'_>, left: bool)
             (arg, arg.span)
         },
         ExprKind::Call(path, [arg])
-            if path_def_id(cx, path)
-                .and_then(|id| match_any_def_paths(cx, id, &[&paths::FROM_STR_METHOD, &paths::FROM_FROM]))
-                .map_or(false, |idx| match idx {
-                    0 => true,
-                    1 => !is_copy(cx, typeck.expr_ty(expr)),
-                    _ => false,
-                }) =>
+            if path_def_id(cx, path).map_or(false, |id| {
+                if match_def_path(cx, id, &paths::FROM_STR_METHOD) {
+                    true
+                } else if cx.tcx.lang_items().from_fn() == Some(id) {
+                    !is_copy(cx, typeck.expr_ty(expr))
+                } else {
+                    false
+                }
+            }) =>
         {
             (arg, arg.span)
         },
diff --git a/src/tools/clippy/clippy_lints/src/operators/op_ref.rs b/src/tools/clippy/clippy_lints/src/operators/op_ref.rs
index 1085e6089441..71b31b5e4a56 100644
--- a/src/tools/clippy/clippy_lints/src/operators/op_ref.rs
+++ b/src/tools/clippy/clippy_lints/src/operators/op_ref.rs
@@ -204,7 +204,7 @@ fn are_equal<'tcx>(cx: &LateContext<'tcx>, middle_ty: Ty<'_>, hir_ty: &rustc_hir
         if let ty::Adt(adt_def, _) = middle_ty.kind();
         if let Some(local_did) = adt_def.did().as_local();
         let item = cx.tcx.hir().expect_item(local_did);
-        let middle_ty_id = item.def_id.to_def_id();
+        let middle_ty_id = item.owner_id.to_def_id();
         if let TyKind::Path(QPath::Resolved(_, path)) = hir_ty.kind;
         if let Res::Def(_, hir_ty_id) = path.res;
 
diff --git a/src/tools/clippy/clippy_lints/src/partial_pub_fields.rs b/src/tools/clippy/clippy_lints/src/partial_pub_fields.rs
new file mode 100644
index 000000000000..f60d9d65b120
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/partial_pub_fields.rs
@@ -0,0 +1,81 @@
+use clippy_utils::diagnostics::span_lint_and_help;
+use rustc_ast::ast::{Item, ItemKind};
+use rustc_lint::{EarlyContext, EarlyLintPass};
+use rustc_session::{declare_lint_pass, declare_tool_lint};
+
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks whether partial fields of a struct are public.
+    ///
+    /// Either make all fields of a type public, or make none of them public
+    ///
+    /// ### Why is this bad?
+    /// Most types should either be:
+    /// * Abstract data types: complex objects with opaque implementation which guard
+    /// interior invariants and expose intentionally limited API to the outside world.
+    /// * Data: relatively simple objects which group a bunch of related attributes together.
+    ///
+    /// ### Example
+    /// ```rust
+    /// pub struct Color {
+    ///     pub r: u8,
+    ///     pub g: u8,
+    ///     b: u8,
+    /// }
+    /// ```
+    /// Use instead:
+    /// ```rust
+    /// pub struct Color {
+    ///     pub r: u8,
+    ///     pub g: u8,
+    ///     pub b: u8,
+    /// }
+    /// ```
+    #[clippy::version = "1.66.0"]
+    pub PARTIAL_PUB_FIELDS,
+    restriction,
+    "partial fields of a struct are public"
+}
+declare_lint_pass!(PartialPubFields => [PARTIAL_PUB_FIELDS]);
+
+impl EarlyLintPass for PartialPubFields {
+    fn check_item(&mut self, cx: &EarlyContext<'_>, item: &Item) {
+        let ItemKind::Struct(ref st, _) = item.kind else {
+            return;
+        };
+
+        let mut fields = st.fields().iter();
+        let Some(first_field) = fields.next() else {
+            // Empty struct.
+            return;
+        };
+        let all_pub = first_field.vis.kind.is_pub();
+        let all_priv = !all_pub;
+
+        let msg = "mixed usage of pub and non-pub fields";
+
+        for field in fields {
+            if all_priv && field.vis.kind.is_pub() {
+                span_lint_and_help(
+                    cx,
+                    PARTIAL_PUB_FIELDS,
+                    field.vis.span,
+                    msg,
+                    None,
+                    "consider using private field here",
+                );
+                return;
+            } else if all_pub && !field.vis.kind.is_pub() {
+                span_lint_and_help(
+                    cx,
+                    PARTIAL_PUB_FIELDS,
+                    field.vis.span,
+                    msg,
+                    None,
+                    "consider using public field here",
+                );
+                return;
+            }
+        }
+    }
+}
diff --git a/src/tools/clippy/clippy_lints/src/partialeq_ne_impl.rs b/src/tools/clippy/clippy_lints/src/partialeq_ne_impl.rs
index 09ac514d014e..5aa3c6f2f934 100644
--- a/src/tools/clippy/clippy_lints/src/partialeq_ne_impl.rs
+++ b/src/tools/clippy/clippy_lints/src/partialeq_ne_impl.rs
@@ -36,7 +36,7 @@ impl<'tcx> LateLintPass<'tcx> for PartialEqNeImpl {
     fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'_>) {
         if_chain! {
             if let ItemKind::Impl(Impl { of_trait: Some(ref trait_ref), items: impl_items, .. }) = item.kind;
-            if !cx.tcx.has_attr(item.def_id.to_def_id(), sym::automatically_derived);
+            if !cx.tcx.has_attr(item.owner_id.to_def_id(), sym::automatically_derived);
             if let Some(eq_trait) = cx.tcx.lang_items().eq_trait();
             if trait_ref.path.res.def_id() == eq_trait;
             then {
diff --git a/src/tools/clippy/clippy_lints/src/pass_by_ref_or_value.rs b/src/tools/clippy/clippy_lints/src/pass_by_ref_or_value.rs
index 45e98de10ace..f9fd3645668a 100644
--- a/src/tools/clippy/clippy_lints/src/pass_by_ref_or_value.rs
+++ b/src/tools/clippy/clippy_lints/src/pass_by_ref_or_value.rs
@@ -139,7 +139,7 @@ impl<'tcx> PassByRefOrValue {
     }
 
     fn check_poly_fn(&mut self, cx: &LateContext<'tcx>, def_id: LocalDefId, decl: &FnDecl<'_>, span: Option<Span>) {
-        if self.avoid_breaking_exported_api && cx.access_levels.is_exported(def_id) {
+        if self.avoid_breaking_exported_api && cx.effective_visibilities.is_exported(def_id) {
             return;
         }
 
@@ -261,7 +261,7 @@ impl<'tcx> LateLintPass<'tcx> for PassByRefOrValue {
         }
 
         if let hir::TraitItemKind::Fn(method_sig, _) = &item.kind {
-            self.check_poly_fn(cx, item.def_id.def_id, method_sig.decl, None);
+            self.check_poly_fn(cx, item.owner_id.def_id, method_sig.decl, None);
         }
     }
 
diff --git a/src/tools/clippy/clippy_lints/src/ptr.rs b/src/tools/clippy/clippy_lints/src/ptr.rs
index d296a150b46d..0d74c90a834f 100644
--- a/src/tools/clippy/clippy_lints/src/ptr.rs
+++ b/src/tools/clippy/clippy_lints/src/ptr.rs
@@ -15,13 +15,17 @@ use rustc_hir::{
     ImplItemKind, ItemKind, Lifetime, LifetimeName, Mutability, Node, Param, ParamName, PatKind, QPath, TraitFn,
     TraitItem, TraitItemKind, TyKind, Unsafety,
 };
+use rustc_infer::infer::TyCtxtInferExt;
+use rustc_infer::traits::{Obligation, ObligationCause};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::hir::nested_filter;
-use rustc_middle::ty::{self, Ty};
+use rustc_middle::ty::{self, Binder, ExistentialPredicate, List, PredicateKind, Ty};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 use rustc_span::source_map::Span;
 use rustc_span::sym;
 use rustc_span::symbol::Symbol;
+use rustc_trait_selection::infer::InferCtxtExt as _;
+use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt as _;
 use std::fmt;
 use std::iter;
 
@@ -160,7 +164,7 @@ impl<'tcx> LateLintPass<'tcx> for Ptr {
             check_mut_from_ref(cx, sig, None);
             for arg in check_fn_args(
                 cx,
-                cx.tcx.fn_sig(item.def_id).skip_binder().inputs(),
+                cx.tcx.fn_sig(item.owner_id).skip_binder().inputs(),
                 sig.decl.inputs,
                 &[],
             )
@@ -184,7 +188,7 @@ impl<'tcx> LateLintPass<'tcx> for Ptr {
         let (item_id, sig, is_trait_item) = match parents.next() {
             Some((_, Node::Item(i))) => {
                 if let ItemKind::Fn(sig, ..) = &i.kind {
-                    (i.def_id, sig, false)
+                    (i.owner_id, sig, false)
                 } else {
                     return;
                 }
@@ -196,14 +200,14 @@ impl<'tcx> LateLintPass<'tcx> for Ptr {
                     return;
                 }
                 if let ImplItemKind::Fn(sig, _) = &i.kind {
-                    (i.def_id, sig, false)
+                    (i.owner_id, sig, false)
                 } else {
                     return;
                 }
             },
             Some((_, Node::TraitItem(i))) => {
                 if let TraitItemKind::Fn(sig, _) = &i.kind {
-                    (i.def_id, sig, true)
+                    (i.owner_id, sig, true)
                 } else {
                     return;
                 }
@@ -384,6 +388,17 @@ enum DerefTy<'tcx> {
     Slice(Option<Span>, Ty<'tcx>),
 }
 impl<'tcx> DerefTy<'tcx> {
+    fn ty(&self, cx: &LateContext<'tcx>) -> Ty<'tcx> {
+        match *self {
+            Self::Str => cx.tcx.types.str_,
+            Self::Path => cx.tcx.mk_adt(
+                cx.tcx.adt_def(cx.tcx.get_diagnostic_item(sym::Path).unwrap()),
+                List::empty(),
+            ),
+            Self::Slice(_, ty) => cx.tcx.mk_slice(ty),
+        }
+    }
+
     fn argless_str(&self) -> &'static str {
         match *self {
             Self::Str => "str",
@@ -552,9 +567,8 @@ fn check_ptr_arg_usage<'tcx>(cx: &LateContext<'tcx>, body: &'tcx Body<'_>, args:
             }
 
             // Check if this is local we care about
-            let args_idx = match path_to_local(e).and_then(|id| self.bindings.get(&id)) {
-                Some(&i) => i,
-                None => return walk_expr(self, e),
+            let Some(&args_idx) = path_to_local(e).and_then(|id| self.bindings.get(&id)) else {
+                return walk_expr(self, e);
             };
             let args = &self.args[args_idx];
             let result = &mut self.results[args_idx];
@@ -582,6 +596,7 @@ fn check_ptr_arg_usage<'tcx>(cx: &LateContext<'tcx>, body: &'tcx Body<'_>, args:
                         let i = expr_args.iter().position(|arg| arg.hir_id == child_id).unwrap_or(0);
                         if expr_sig(self.cx, f).and_then(|sig| sig.input(i)).map_or(true, |ty| {
                             match *ty.skip_binder().peel_refs().kind() {
+                                ty::Dynamic(preds, _, _) => !matches_preds(self.cx, args.deref_ty.ty(self.cx), preds),
                                 ty::Param(_) => true,
                                 ty::Adt(def, _) => def.did() == args.ty_did,
                                 _ => false,
@@ -609,14 +624,15 @@ fn check_ptr_arg_usage<'tcx>(cx: &LateContext<'tcx>, body: &'tcx Body<'_>, args:
                             }
                         }
 
-                        let id = if let Some(x) = self.cx.typeck_results().type_dependent_def_id(e.hir_id) {
-                            x
-                        } else {
+                        let Some(id) = self.cx.typeck_results().type_dependent_def_id(e.hir_id) else {
                             set_skip_flag();
                             return;
                         };
 
                         match *self.cx.tcx.fn_sig(id).skip_binder().inputs()[i].peel_refs().kind() {
+                            ty::Dynamic(preds, _, _) if !matches_preds(self.cx, args.deref_ty.ty(self.cx), preds) => {
+                                set_skip_flag();
+                            },
                             ty::Param(_) => {
                                 set_skip_flag();
                             },
@@ -668,6 +684,30 @@ fn check_ptr_arg_usage<'tcx>(cx: &LateContext<'tcx>, body: &'tcx Body<'_>, args:
     v.results
 }
 
+fn matches_preds<'tcx>(
+    cx: &LateContext<'tcx>,
+    ty: Ty<'tcx>,
+    preds: &'tcx [Binder<'tcx, ExistentialPredicate<'tcx>>],
+) -> bool {
+    let infcx = cx.tcx.infer_ctxt().build();
+    preds.iter().all(|&p| match cx.tcx.erase_late_bound_regions(p) {
+        ExistentialPredicate::Trait(p) => infcx
+            .type_implements_trait(p.def_id, ty, p.substs, cx.param_env)
+            .must_apply_modulo_regions(),
+        ExistentialPredicate::Projection(p) => infcx.predicate_must_hold_modulo_regions(&Obligation::new(
+            ObligationCause::dummy(),
+            cx.param_env,
+            cx.tcx.mk_predicate(Binder::bind_with_vars(
+                PredicateKind::Projection(p.with_self_ty(cx.tcx, ty)),
+                List::empty(),
+            )),
+        )),
+        ExistentialPredicate::AutoTrait(p) => infcx
+            .type_implements_trait(p, ty, List::empty(), cx.param_env)
+            .must_apply_modulo_regions(),
+    })
+}
+
 fn get_rptr_lm<'tcx>(ty: &'tcx hir::Ty<'tcx>) -> Option<(&'tcx Lifetime, Mutability, Span)> {
     if let TyKind::Rptr(lt, ref m) = ty.kind {
         Some((lt, m.mutbl, ty.span))
diff --git a/src/tools/clippy/clippy_lints/src/ptr_offset_with_cast.rs b/src/tools/clippy/clippy_lints/src/ptr_offset_with_cast.rs
index b0a5d1a67582..72dda67c72b2 100644
--- a/src/tools/clippy/clippy_lints/src/ptr_offset_with_cast.rs
+++ b/src/tools/clippy/clippy_lints/src/ptr_offset_with_cast.rs
@@ -49,15 +49,13 @@ declare_lint_pass!(PtrOffsetWithCast => [PTR_OFFSET_WITH_CAST]);
 impl<'tcx> LateLintPass<'tcx> for PtrOffsetWithCast {
     fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
         // Check if the expressions is a ptr.offset or ptr.wrapping_offset method call
-        let (receiver_expr, arg_expr, method) = match expr_as_ptr_offset_call(cx, expr) {
-            Some(call_arg) => call_arg,
-            None => return,
+        let Some((receiver_expr, arg_expr, method)) = expr_as_ptr_offset_call(cx, expr) else {
+            return
         };
 
         // Check if the argument to the method call is a cast from usize
-        let cast_lhs_expr = match expr_as_cast_from_usize(cx, arg_expr) {
-            Some(cast_lhs_expr) => cast_lhs_expr,
-            None => return,
+        let Some(cast_lhs_expr) = expr_as_cast_from_usize(cx, arg_expr) else {
+            return
         };
 
         let msg = format!("use of `{method}` with a `usize` casted to an `isize`");
diff --git a/src/tools/clippy/clippy_lints/src/question_mark.rs b/src/tools/clippy/clippy_lints/src/question_mark.rs
index 328371fd602f..bb86fb3b7d42 100644
--- a/src/tools/clippy/clippy_lints/src/question_mark.rs
+++ b/src/tools/clippy/clippy_lints/src/question_mark.rs
@@ -94,7 +94,7 @@ fn check_is_none_or_err_and_early_return<'tcx>(cx: &LateContext<'tcx>, expr: &Ex
         then {
             let mut applicability = Applicability::MachineApplicable;
             let receiver_str = snippet_with_applicability(cx, caller.span, "..", &mut applicability);
-            let by_ref = !caller_ty.is_copy_modulo_regions(cx.tcx.at(caller.span), cx.param_env) &&
+            let by_ref = !caller_ty.is_copy_modulo_regions(cx.tcx, cx.param_env) &&
                 !matches!(caller.kind, ExprKind::Call(..) | ExprKind::MethodCall(..));
             let sugg = if let Some(else_inner) = r#else {
                 if eq_expr_value(cx, caller, peel_blocks(else_inner)) {
diff --git a/src/tools/clippy/clippy_lints/src/redundant_clone.rs b/src/tools/clippy/clippy_lints/src/redundant_clone.rs
index 9fd86331ec75..aedbe08e3e46 100644
--- a/src/tools/clippy/clippy_lints/src/redundant_clone.rs
+++ b/src/tools/clippy/clippy_lints/src/redundant_clone.rs
@@ -1,25 +1,18 @@
 use clippy_utils::diagnostics::{span_lint_hir, span_lint_hir_and_then};
+use clippy_utils::mir::{visit_local_usage, LocalUsage, PossibleBorrowerMap};
 use clippy_utils::source::snippet_opt;
 use clippy_utils::ty::{has_drop, is_copy, is_type_diagnostic_item, walk_ptrs_ty_depth};
 use clippy_utils::{fn_has_unsatisfiable_preds, match_def_path, paths};
 use if_chain::if_chain;
-use rustc_data_structures::fx::FxHashMap;
 use rustc_errors::Applicability;
 use rustc_hir::intravisit::FnKind;
 use rustc_hir::{def_id, Body, FnDecl, HirId};
-use rustc_index::bit_set::{BitSet, HybridBitSet};
 use rustc_lint::{LateContext, LateLintPass};
-use rustc_middle::mir::{
-    self, traversal,
-    visit::{MutatingUseContext, NonMutatingUseContext, PlaceContext, Visitor as _},
-    Mutability,
-};
-use rustc_middle::ty::{self, visit::TypeVisitor, Ty};
-use rustc_mir_dataflow::{Analysis, AnalysisDomain, CallReturnPlaces, GenKill, GenKillAnalysis, ResultsCursor};
+use rustc_middle::mir;
+use rustc_middle::ty::{self, Ty};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 use rustc_span::source_map::{BytePos, Span};
 use rustc_span::sym;
-use std::ops::ControlFlow;
 
 macro_rules! unwrap_or_continue {
     ($x:expr) => {
@@ -89,21 +82,7 @@ impl<'tcx> LateLintPass<'tcx> for RedundantClone {
 
         let mir = cx.tcx.optimized_mir(def_id.to_def_id());
 
-        let possible_origin = {
-            let mut vis = PossibleOriginVisitor::new(mir);
-            vis.visit_body(mir);
-            vis.into_map(cx)
-        };
-        let maybe_storage_live_result = MaybeStorageLive
-            .into_engine(cx.tcx, mir)
-            .pass_name("redundant_clone")
-            .iterate_to_fixpoint()
-            .into_results_cursor(mir);
-        let mut possible_borrower = {
-            let mut vis = PossibleBorrowerVisitor::new(cx, mir, possible_origin);
-            vis.visit_body(mir);
-            vis.into_map(cx, maybe_storage_live_result)
-        };
+        let mut possible_borrower = PossibleBorrowerMap::new(cx, mir);
 
         for (bb, bbdata) in mir.basic_blocks.iter_enumerated() {
             let terminator = bbdata.terminator();
@@ -374,403 +353,40 @@ struct CloneUsage {
     /// Whether the clone value is mutated.
     clone_consumed_or_mutated: bool,
 }
+
 fn visit_clone_usage(cloned: mir::Local, clone: mir::Local, mir: &mir::Body<'_>, bb: mir::BasicBlock) -> CloneUsage {
-    struct V {
-        cloned: mir::Local,
-        clone: mir::Local,
-        result: CloneUsage,
-    }
-    impl<'tcx> mir::visit::Visitor<'tcx> for V {
-        fn visit_basic_block_data(&mut self, block: mir::BasicBlock, data: &mir::BasicBlockData<'tcx>) {
-            let statements = &data.statements;
-            for (statement_index, statement) in statements.iter().enumerate() {
-                self.visit_statement(statement, mir::Location { block, statement_index });
-            }
-
-            self.visit_terminator(
-                data.terminator(),
-                mir::Location {
-                    block,
-                    statement_index: statements.len(),
-                },
-            );
-        }
-
-        fn visit_place(&mut self, place: &mir::Place<'tcx>, ctx: PlaceContext, loc: mir::Location) {
-            let local = place.local;
-
-            if local == self.cloned
-                && !matches!(
-                    ctx,
-                    PlaceContext::MutatingUse(MutatingUseContext::Drop) | PlaceContext::NonUse(_)
-                )
-            {
-                self.result.cloned_used = true;
-                self.result.cloned_consume_or_mutate_loc = self.result.cloned_consume_or_mutate_loc.or_else(|| {
-                    matches!(
-                        ctx,
-                        PlaceContext::NonMutatingUse(NonMutatingUseContext::Move)
-                            | PlaceContext::MutatingUse(MutatingUseContext::Borrow)
-                    )
-                    .then(|| loc)
-                });
-            } else if local == self.clone {
-                match ctx {
-                    PlaceContext::NonMutatingUse(NonMutatingUseContext::Move)
-                    | PlaceContext::MutatingUse(MutatingUseContext::Borrow) => {
-                        self.result.clone_consumed_or_mutated = true;
-                    },
-                    _ => {},
-                }
-            }
-        }
-    }
-
-    let init = CloneUsage {
-        cloned_used: false,
-        cloned_consume_or_mutate_loc: None,
-        // Consider non-temporary clones consumed.
-        // TODO: Actually check for mutation of non-temporaries.
-        clone_consumed_or_mutated: mir.local_kind(clone) != mir::LocalKind::Temp,
-    };
-    traversal::ReversePostorder::new(mir, bb)
-        .skip(1)
-        .fold(init, |usage, (tbb, tdata)| {
-            // Short-circuit
-            if (usage.cloned_used && usage.clone_consumed_or_mutated) ||
-                // Give up on loops
-                tdata.terminator().successors().any(|s| s == bb)
-            {
-                return CloneUsage {
-                    cloned_used: true,
-                    clone_consumed_or_mutated: true,
-                    ..usage
-                };
-            }
-
-            let mut v = V {
-                cloned,
-                clone,
-                result: usage,
-            };
-            v.visit_basic_block_data(tbb, tdata);
-            v.result
-        })
-}
-
-/// Determines liveness of each local purely based on `StorageLive`/`Dead`.
-#[derive(Copy, Clone)]
-struct MaybeStorageLive;
-
-impl<'tcx> AnalysisDomain<'tcx> for MaybeStorageLive {
-    type Domain = BitSet<mir::Local>;
-    const NAME: &'static str = "maybe_storage_live";
-
-    fn bottom_value(&self, body: &mir::Body<'tcx>) -> Self::Domain {
-        // bottom = dead
-        BitSet::new_empty(body.local_decls.len())
-    }
-
-    fn initialize_start_block(&self, body: &mir::Body<'tcx>, state: &mut Self::Domain) {
-        for arg in body.args_iter() {
-            state.insert(arg);
-        }
-    }
-}
-
-impl<'tcx> GenKillAnalysis<'tcx> for MaybeStorageLive {
-    type Idx = mir::Local;
-
-    fn statement_effect(&self, trans: &mut impl GenKill<Self::Idx>, stmt: &mir::Statement<'tcx>, _: mir::Location) {
-        match stmt.kind {
-            mir::StatementKind::StorageLive(l) => trans.gen(l),
-            mir::StatementKind::StorageDead(l) => trans.kill(l),
-            _ => (),
-        }
-    }
-
-    fn terminator_effect(
-        &self,
-        _trans: &mut impl GenKill<Self::Idx>,
-        _terminator: &mir::Terminator<'tcx>,
-        _loc: mir::Location,
-    ) {
-    }
-
-    fn call_return_effect(
-        &self,
-        _trans: &mut impl GenKill<Self::Idx>,
-        _block: mir::BasicBlock,
-        _return_places: CallReturnPlaces<'_, 'tcx>,
-    ) {
-        // Nothing to do when a call returns successfully
-    }
-}
-
-/// Collects the possible borrowers of each local.
-/// For example, `b = &a; c = &a;` will make `b` and (transitively) `c`
-/// possible borrowers of `a`.
-struct PossibleBorrowerVisitor<'a, 'tcx> {
-    possible_borrower: TransitiveRelation,
-    body: &'a mir::Body<'tcx>,
-    cx: &'a LateContext<'tcx>,
-    possible_origin: FxHashMap<mir::Local, HybridBitSet<mir::Local>>,
-}
-
-impl<'a, 'tcx> PossibleBorrowerVisitor<'a, 'tcx> {
-    fn new(
-        cx: &'a LateContext<'tcx>,
-        body: &'a mir::Body<'tcx>,
-        possible_origin: FxHashMap<mir::Local, HybridBitSet<mir::Local>>,
-    ) -> Self {
-        Self {
-            possible_borrower: TransitiveRelation::default(),
-            cx,
-            body,
-            possible_origin,
-        }
-    }
-
-    fn into_map(
-        self,
-        cx: &LateContext<'tcx>,
-        maybe_live: ResultsCursor<'tcx, 'tcx, MaybeStorageLive>,
-    ) -> PossibleBorrowerMap<'a, 'tcx> {
-        let mut map = FxHashMap::default();
-        for row in (1..self.body.local_decls.len()).map(mir::Local::from_usize) {
-            if is_copy(cx, self.body.local_decls[row].ty) {
-                continue;
-            }
-
-            let mut borrowers = self.possible_borrower.reachable_from(row, self.body.local_decls.len());
-            borrowers.remove(mir::Local::from_usize(0));
-            if !borrowers.is_empty() {
-                map.insert(row, borrowers);
-            }
-        }
-
-        let bs = BitSet::new_empty(self.body.local_decls.len());
-        PossibleBorrowerMap {
-            map,
-            maybe_live,
-            bitset: (bs.clone(), bs),
-        }
-    }
-}
-
-impl<'a, 'tcx> mir::visit::Visitor<'tcx> for PossibleBorrowerVisitor<'a, 'tcx> {
-    fn visit_assign(&mut self, place: &mir::Place<'tcx>, rvalue: &mir::Rvalue<'_>, _location: mir::Location) {
-        let lhs = place.local;
-        match rvalue {
-            mir::Rvalue::Ref(_, _, borrowed) => {
-                self.possible_borrower.add(borrowed.local, lhs);
-            },
-            other => {
-                if ContainsRegion
-                    .visit_ty(place.ty(&self.body.local_decls, self.cx.tcx).ty)
-                    .is_continue()
-                {
-                    return;
-                }
-                rvalue_locals(other, |rhs| {
-                    if lhs != rhs {
-                        self.possible_borrower.add(rhs, lhs);
-                    }
-                });
-            },
-        }
-    }
-
-    fn visit_terminator(&mut self, terminator: &mir::Terminator<'_>, _loc: mir::Location) {
-        if let mir::TerminatorKind::Call {
-            args,
-            destination: mir::Place { local: dest, .. },
-            ..
-        } = &terminator.kind
-        {
-            // TODO add doc
-            // If the call returns something with lifetimes,
-            // let's conservatively assume the returned value contains lifetime of all the arguments.
-            // For example, given `let y: Foo<'a> = foo(x)`, `y` is considered to be a possible borrower of `x`.
-
-            let mut immutable_borrowers = vec![];
-            let mut mutable_borrowers = vec![];
-
-            for op in args {
-                match op {
-                    mir::Operand::Copy(p) | mir::Operand::Move(p) => {
-                        if let ty::Ref(_, _, Mutability::Mut) = self.body.local_decls[p.local].ty.kind() {
-                            mutable_borrowers.push(p.local);
-                        } else {
-                            immutable_borrowers.push(p.local);
-                        }
-                    },
-                    mir::Operand::Constant(..) => (),
-                }
-            }
-
-            let mut mutable_variables: Vec<mir::Local> = mutable_borrowers
-                .iter()
-                .filter_map(|r| self.possible_origin.get(r))
-                .flat_map(HybridBitSet::iter)
-                .collect();
-
-            if ContainsRegion.visit_ty(self.body.local_decls[*dest].ty).is_break() {
-                mutable_variables.push(*dest);
-            }
-
-            for y in mutable_variables {
-                for x in &immutable_borrowers {
-                    self.possible_borrower.add(*x, y);
-                }
-                for x in &mutable_borrowers {
-                    self.possible_borrower.add(*x, y);
-                }
-            }
-        }
-    }
-}
-
-/// Collect possible borrowed for every `&mut` local.
-/// For example, `_1 = &mut _2` generate _1: {_2,...}
-/// Known Problems: not sure all borrowed are tracked
-struct PossibleOriginVisitor<'a, 'tcx> {
-    possible_origin: TransitiveRelation,
-    body: &'a mir::Body<'tcx>,
-}
-
-impl<'a, 'tcx> PossibleOriginVisitor<'a, 'tcx> {
-    fn new(body: &'a mir::Body<'tcx>) -> Self {
-        Self {
-            possible_origin: TransitiveRelation::default(),
-            body,
-        }
-    }
-
-    fn into_map(self, cx: &LateContext<'tcx>) -> FxHashMap<mir::Local, HybridBitSet<mir::Local>> {
-        let mut map = FxHashMap::default();
-        for row in (1..self.body.local_decls.len()).map(mir::Local::from_usize) {
-            if is_copy(cx, self.body.local_decls[row].ty) {
-                continue;
-            }
-
-            let mut borrowers = self.possible_origin.reachable_from(row, self.body.local_decls.len());
-            borrowers.remove(mir::Local::from_usize(0));
-            if !borrowers.is_empty() {
-                map.insert(row, borrowers);
-            }
-        }
-        map
-    }
-}
-
-impl<'a, 'tcx> mir::visit::Visitor<'tcx> for PossibleOriginVisitor<'a, 'tcx> {
-    fn visit_assign(&mut self, place: &mir::Place<'tcx>, rvalue: &mir::Rvalue<'_>, _location: mir::Location) {
-        let lhs = place.local;
-        match rvalue {
-            // Only consider `&mut`, which can modify origin place
-            mir::Rvalue::Ref(_, rustc_middle::mir::BorrowKind::Mut { .. }, borrowed) |
-            // _2: &mut _;
-            // _3 = move _2
-            mir::Rvalue::Use(mir::Operand::Move(borrowed))  |
-            // _3 = move _2 as &mut _;
-            mir::Rvalue::Cast(_, mir::Operand::Move(borrowed), _)
-                => {
-                self.possible_origin.add(lhs, borrowed.local);
-            },
-            _ => {},
-        }
-    }
-}
-
-struct ContainsRegion;
-
-impl TypeVisitor<'_> for ContainsRegion {
-    type BreakTy = ();
-
-    fn visit_region(&mut self, _: ty::Region<'_>) -> ControlFlow<Self::BreakTy> {
-        ControlFlow::BREAK
-    }
-}
-
-fn rvalue_locals(rvalue: &mir::Rvalue<'_>, mut visit: impl FnMut(mir::Local)) {
-    use rustc_middle::mir::Rvalue::{Aggregate, BinaryOp, Cast, CheckedBinaryOp, Repeat, UnaryOp, Use};
-
-    let mut visit_op = |op: &mir::Operand<'_>| match op {
-        mir::Operand::Copy(p) | mir::Operand::Move(p) => visit(p.local),
-        mir::Operand::Constant(..) => (),
-    };
-
-    match rvalue {
-        Use(op) | Repeat(op, _) | Cast(_, op, _) | UnaryOp(_, op) => visit_op(op),
-        Aggregate(_, ops) => ops.iter().for_each(visit_op),
-        BinaryOp(_, box (lhs, rhs)) | CheckedBinaryOp(_, box (lhs, rhs)) => {
-            visit_op(lhs);
-            visit_op(rhs);
+    if let Some((
+        LocalUsage {
+            local_use_locs: cloned_use_locs,
+            local_consume_or_mutate_locs: cloned_consume_or_mutate_locs,
         },
-        _ => (),
-    }
-}
-
-/// Result of `PossibleBorrowerVisitor`.
-struct PossibleBorrowerMap<'a, 'tcx> {
-    /// Mapping `Local -> its possible borrowers`
-    map: FxHashMap<mir::Local, HybridBitSet<mir::Local>>,
-    maybe_live: ResultsCursor<'a, 'tcx, MaybeStorageLive>,
-    // Caches to avoid allocation of `BitSet` on every query
-    bitset: (BitSet<mir::Local>, BitSet<mir::Local>),
-}
-
-impl PossibleBorrowerMap<'_, '_> {
-    /// Returns true if the set of borrowers of `borrowed` living at `at` matches with `borrowers`.
-    fn only_borrowers(&mut self, borrowers: &[mir::Local], borrowed: mir::Local, at: mir::Location) -> bool {
-        self.maybe_live.seek_after_primary_effect(at);
-
-        self.bitset.0.clear();
-        let maybe_live = &mut self.maybe_live;
-        if let Some(bitset) = self.map.get(&borrowed) {
-            for b in bitset.iter().filter(move |b| maybe_live.contains(*b)) {
-                self.bitset.0.insert(b);
-            }
-        } else {
-            return false;
+        LocalUsage {
+            local_use_locs: _,
+            local_consume_or_mutate_locs: clone_consume_or_mutate_locs,
+        },
+    )) = visit_local_usage(
+        &[cloned, clone],
+        mir,
+        mir::Location {
+            block: bb,
+            statement_index: mir.basic_blocks[bb].statements.len(),
+        },
+    )
+    .map(|mut vec| (vec.remove(0), vec.remove(0)))
+    {
+        CloneUsage {
+            cloned_used: !cloned_use_locs.is_empty(),
+            cloned_consume_or_mutate_loc: cloned_consume_or_mutate_locs.first().copied(),
+            // Consider non-temporary clones consumed.
+            // TODO: Actually check for mutation of non-temporaries.
+            clone_consumed_or_mutated: mir.local_kind(clone) != mir::LocalKind::Temp
+                || !clone_consume_or_mutate_locs.is_empty(),
         }
-
-        self.bitset.1.clear();
-        for b in borrowers {
-            self.bitset.1.insert(*b);
+    } else {
+        CloneUsage {
+            cloned_used: true,
+            cloned_consume_or_mutate_loc: None,
+            clone_consumed_or_mutated: true,
         }
-
-        self.bitset.0 == self.bitset.1
-    }
-
-    fn local_is_alive_at(&mut self, local: mir::Local, at: mir::Location) -> bool {
-        self.maybe_live.seek_after_primary_effect(at);
-        self.maybe_live.contains(local)
-    }
-}
-
-#[derive(Default)]
-struct TransitiveRelation {
-    relations: FxHashMap<mir::Local, Vec<mir::Local>>,
-}
-impl TransitiveRelation {
-    fn add(&mut self, a: mir::Local, b: mir::Local) {
-        self.relations.entry(a).or_default().push(b);
-    }
-
-    fn reachable_from(&self, a: mir::Local, domain_size: usize) -> HybridBitSet<mir::Local> {
-        let mut seen = HybridBitSet::new_empty(domain_size);
-        let mut stack = vec![a];
-        while let Some(u) = stack.pop() {
-            if let Some(edges) = self.relations.get(&u) {
-                for &v in edges {
-                    if seen.insert(v) {
-                        stack.push(v);
-                    }
-                }
-            }
-        }
-        seen
     }
 }
diff --git a/src/tools/clippy/clippy_lints/src/redundant_pub_crate.rs b/src/tools/clippy/clippy_lints/src/redundant_pub_crate.rs
index 464f6827e1d5..26075e9f70fa 100644
--- a/src/tools/clippy/clippy_lints/src/redundant_pub_crate.rs
+++ b/src/tools/clippy/clippy_lints/src/redundant_pub_crate.rs
@@ -46,12 +46,12 @@ impl_lint_pass!(RedundantPubCrate => [REDUNDANT_PUB_CRATE]);
 impl<'tcx> LateLintPass<'tcx> for RedundantPubCrate {
     fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'tcx>) {
         if_chain! {
-            if cx.tcx.visibility(item.def_id.def_id) == ty::Visibility::Restricted(CRATE_DEF_ID.to_def_id());
-            if !cx.access_levels.is_exported(item.def_id.def_id) && self.is_exported.last() == Some(&false);
+            if cx.tcx.visibility(item.owner_id.def_id) == ty::Visibility::Restricted(CRATE_DEF_ID.to_def_id());
+            if !cx.effective_visibilities.is_exported(item.owner_id.def_id) && self.is_exported.last() == Some(&false);
             if is_not_macro_export(item);
             then {
                 let span = item.span.with_hi(item.ident.span.hi());
-                let descr = cx.tcx.def_kind(item.def_id).descr(item.def_id.to_def_id());
+                let descr = cx.tcx.def_kind(item.owner_id).descr(item.owner_id.to_def_id());
                 span_lint_and_then(
                     cx,
                     REDUNDANT_PUB_CRATE,
@@ -70,7 +70,7 @@ impl<'tcx> LateLintPass<'tcx> for RedundantPubCrate {
         }
 
         if let ItemKind::Mod { .. } = item.kind {
-            self.is_exported.push(cx.access_levels.is_exported(item.def_id.def_id));
+            self.is_exported.push(cx.effective_visibilities.is_exported(item.owner_id.def_id));
         }
     }
 
diff --git a/src/tools/clippy/clippy_lints/src/ref_option_ref.rs b/src/tools/clippy/clippy_lints/src/ref_option_ref.rs
index 42514f861be1..f21b3ea6c3b0 100644
--- a/src/tools/clippy/clippy_lints/src/ref_option_ref.rs
+++ b/src/tools/clippy/clippy_lints/src/ref_option_ref.rs
@@ -52,7 +52,8 @@ impl<'tcx> LateLintPass<'tcx> for RefOptionRef {
                 GenericArg::Type(inner_ty) => Some(inner_ty),
                 _ => None,
             });
-            if let TyKind::Rptr(_, _) = inner_ty.kind;
+            if let TyKind::Rptr(_, ref inner_mut_ty) = inner_ty.kind;
+            if inner_mut_ty.mutbl == Mutability::Not;
 
             then {
                 span_lint_and_sugg(
diff --git a/src/tools/clippy/clippy_lints/src/return_self_not_must_use.rs b/src/tools/clippy/clippy_lints/src/return_self_not_must_use.rs
index 16d702a3868d..b77faf7322bd 100644
--- a/src/tools/clippy/clippy_lints/src/return_self_not_must_use.rs
+++ b/src/tools/clippy/clippy_lints/src/return_self_not_must_use.rs
@@ -74,7 +74,7 @@ fn check_method(cx: &LateContext<'_>, decl: &FnDecl<'_>, fn_def: LocalDefId, spa
         if !in_external_macro(cx.sess(), span);
         if decl.implicit_self.has_implicit_self();
         // We only show this warning for public exported methods.
-        if cx.access_levels.is_exported(fn_def);
+        if cx.effective_visibilities.is_exported(fn_def);
         // We don't want to emit this lint if the `#[must_use]` attribute is already there.
         if !cx.tcx.hir().attrs(hir_id).iter().any(|attr| attr.has_name(sym::must_use));
         if cx.tcx.visibility(fn_def.to_def_id()).is_public();
@@ -128,7 +128,7 @@ impl<'tcx> LateLintPass<'tcx> for ReturnSelfNotMustUse {
 
     fn check_trait_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx TraitItem<'tcx>) {
         if let TraitItemKind::Fn(ref sig, _) = item.kind {
-            check_method(cx, sig.decl, item.def_id.def_id, item.span, item.hir_id());
+            check_method(cx, sig.decl, item.owner_id.def_id, item.span, item.hir_id());
         }
     }
 }
diff --git a/src/tools/clippy/clippy_lints/src/same_name_method.rs b/src/tools/clippy/clippy_lints/src/same_name_method.rs
index 4249063d2d47..caab5851bafc 100644
--- a/src/tools/clippy/clippy_lints/src/same_name_method.rs
+++ b/src/tools/clippy/clippy_lints/src/same_name_method.rs
@@ -52,7 +52,7 @@ impl<'tcx> LateLintPass<'tcx> for SameNameMethod {
         let mut map = FxHashMap::<Res, ExistingName>::default();
 
         for id in cx.tcx.hir().items() {
-            if matches!(cx.tcx.def_kind(id.def_id), DefKind::Impl)
+            if matches!(cx.tcx.def_kind(id.owner_id), DefKind::Impl)
                 && let item = cx.tcx.hir().item(id)
                 && let ItemKind::Impl(Impl {
                   items,
diff --git a/src/tools/clippy/clippy_lints/src/self_named_constructors.rs b/src/tools/clippy/clippy_lints/src/self_named_constructors.rs
index 1ac538f4c7c0..71b387c66a33 100644
--- a/src/tools/clippy/clippy_lints/src/self_named_constructors.rs
+++ b/src/tools/clippy/clippy_lints/src/self_named_constructors.rs
@@ -53,7 +53,7 @@ impl<'tcx> LateLintPass<'tcx> for SelfNamedConstructors {
 
         let parent = cx.tcx.hir().get_parent_item(impl_item.hir_id()).def_id;
         let item = cx.tcx.hir().expect_item(parent);
-        let self_ty = cx.tcx.type_of(item.def_id);
+        let self_ty = cx.tcx.type_of(item.owner_id);
         let ret_ty = return_ty(cx, impl_item.hir_id());
 
         // Do not check trait impls
diff --git a/src/tools/clippy/clippy_lints/src/shadow.rs b/src/tools/clippy/clippy_lints/src/shadow.rs
index 5dcdab5b8ab9..87f966ced0df 100644
--- a/src/tools/clippy/clippy_lints/src/shadow.rs
+++ b/src/tools/clippy/clippy_lints/src/shadow.rs
@@ -106,10 +106,7 @@ impl_lint_pass!(Shadow => [SHADOW_SAME, SHADOW_REUSE, SHADOW_UNRELATED]);
 
 impl<'tcx> LateLintPass<'tcx> for Shadow {
     fn check_pat(&mut self, cx: &LateContext<'tcx>, pat: &'tcx Pat<'_>) {
-        let (id, ident) = match pat.kind {
-            PatKind::Binding(_, hir_id, ident, _) => (hir_id, ident),
-            _ => return,
-        };
+        let PatKind::Binding(_, id, ident, _) = pat.kind else { return };
 
         if pat.span.desugaring_kind().is_some() {
             return;
diff --git a/src/tools/clippy/clippy_lints/src/suspicious_trait_impl.rs b/src/tools/clippy/clippy_lints/src/suspicious_trait_impl.rs
index b57b484bdc89..6271ea027314 100644
--- a/src/tools/clippy/clippy_lints/src/suspicious_trait_impl.rs
+++ b/src/tools/clippy/clippy_lints/src/suspicious_trait_impl.rs
@@ -60,8 +60,8 @@ impl<'tcx> LateLintPass<'tcx> for SuspiciousImpl {
         if_chain! {
             if let hir::ExprKind::Binary(binop, _, _) | hir::ExprKind::AssignOp(binop, ..) = expr.kind;
             if let Some((binop_trait_lang, op_assign_trait_lang)) = binop_traits(binop.node);
-            if let Ok(binop_trait_id) = cx.tcx.lang_items().require(binop_trait_lang);
-            if let Ok(op_assign_trait_id) = cx.tcx.lang_items().require(op_assign_trait_lang);
+            if let Some(binop_trait_id) = cx.tcx.lang_items().get(binop_trait_lang);
+            if let Some(op_assign_trait_id) = cx.tcx.lang_items().get(op_assign_trait_lang);
 
             // Check for more than one binary operation in the implemented function
             // Linting when multiple operations are involved can result in false positives
@@ -78,7 +78,7 @@ impl<'tcx> LateLintPass<'tcx> for SuspiciousImpl {
                 (&OP_ASSIGN_TRAITS, SUSPICIOUS_OP_ASSIGN_IMPL),
             ]
                 .iter()
-                .find(|&(ts, _)| ts.iter().any(|&t| Ok(trait_id) == cx.tcx.lang_items().require(t)));
+                .find(|&(ts, _)| ts.iter().any(|&t| Some(trait_id) == cx.tcx.lang_items().get(t)));
             if count_binops(body.value) == 1;
             then {
                 span_lint(
diff --git a/src/tools/clippy/clippy_lints/src/trailing_empty_array.rs b/src/tools/clippy/clippy_lints/src/trailing_empty_array.rs
index 58cc057a39ed..8cf3efc8dc73 100644
--- a/src/tools/clippy/clippy_lints/src/trailing_empty_array.rs
+++ b/src/tools/clippy/clippy_lints/src/trailing_empty_array.rs
@@ -46,7 +46,7 @@ impl<'tcx> LateLintPass<'tcx> for TrailingEmptyArray {
                 None,
                 &format!(
                     "consider annotating `{}` with `#[repr(C)]` or another `repr` attribute",
-                    cx.tcx.def_path_str(item.def_id.to_def_id())
+                    cx.tcx.def_path_str(item.owner_id.to_def_id())
                 ),
             );
         }
diff --git a/src/tools/clippy/clippy_lints/src/transmute/transmute_undefined_repr.rs b/src/tools/clippy/clippy_lints/src/transmute/transmute_undefined_repr.rs
index 1c99a02e6c71..3d4bbbf648c6 100644
--- a/src/tools/clippy/clippy_lints/src/transmute/transmute_undefined_repr.rs
+++ b/src/tools/clippy/clippy_lints/src/transmute/transmute_undefined_repr.rs
@@ -5,7 +5,6 @@ use rustc_hir::Expr;
 use rustc_lint::LateContext;
 use rustc_middle::ty::SubstsRef;
 use rustc_middle::ty::{self, IntTy, Ty, TypeAndMut, UintTy};
-use rustc_span::DUMMY_SP;
 
 #[expect(clippy::too_many_lines)]
 pub(super) fn check<'tcx>(
@@ -28,24 +27,32 @@ pub(super) fn check<'tcx>(
 
             // `Repr(C)` <-> unordered type.
             // If the first field of the `Repr(C)` type matches then the transmute is ok
-            (ReducedTy::OrderedFields(_, Some(from_sub_ty)), ReducedTy::UnorderedFields(to_sub_ty))
-            | (ReducedTy::UnorderedFields(from_sub_ty), ReducedTy::OrderedFields(_, Some(to_sub_ty))) => {
+            (
+                ReducedTy::OrderedFields(_, Some(from_sub_ty)),
+                ReducedTy::UnorderedFields(to_sub_ty),
+            )
+            | (
+                ReducedTy::UnorderedFields(from_sub_ty),
+                ReducedTy::OrderedFields(_, Some(to_sub_ty)),
+            ) => {
                 from_ty = from_sub_ty;
                 to_ty = to_sub_ty;
                 continue;
-            },
-            (ReducedTy::OrderedFields(_, Some(from_sub_ty)), ReducedTy::Other(to_sub_ty)) if reduced_tys.to_fat_ptr => {
+            }
+            (ReducedTy::OrderedFields(_, Some(from_sub_ty)), ReducedTy::Other(to_sub_ty))
+                if reduced_tys.to_fat_ptr =>
+            {
                 from_ty = from_sub_ty;
                 to_ty = to_sub_ty;
                 continue;
-            },
+            }
             (ReducedTy::Other(from_sub_ty), ReducedTy::OrderedFields(_, Some(to_sub_ty)))
                 if reduced_tys.from_fat_ptr =>
             {
                 from_ty = from_sub_ty;
                 to_ty = to_sub_ty;
                 continue;
-            },
+            }
 
             // ptr <-> ptr
             (ReducedTy::Other(from_sub_ty), ReducedTy::Other(to_sub_ty))
@@ -55,19 +62,19 @@ pub(super) fn check<'tcx>(
                 from_ty = from_sub_ty;
                 to_ty = to_sub_ty;
                 continue;
-            },
+            }
 
             // fat ptr <-> (*size, *size)
             (ReducedTy::Other(_), ReducedTy::UnorderedFields(to_ty))
                 if reduced_tys.from_fat_ptr && is_size_pair(to_ty) =>
             {
                 return false;
-            },
+            }
             (ReducedTy::UnorderedFields(from_ty), ReducedTy::Other(_))
                 if reduced_tys.to_fat_ptr && is_size_pair(from_ty) =>
             {
                 return false;
-            },
+            }
 
             // fat ptr -> some struct | some struct -> fat ptr
             (ReducedTy::Other(_), _) if reduced_tys.from_fat_ptr => {
@@ -78,12 +85,14 @@ pub(super) fn check<'tcx>(
                     &format!("transmute from `{from_ty_orig}` which has an undefined layout"),
                     |diag| {
                         if from_ty_orig.peel_refs() != from_ty.peel_refs() {
-                            diag.note(&format!("the contained type `{from_ty}` has an undefined layout"));
+                            diag.note(&format!(
+                                "the contained type `{from_ty}` has an undefined layout"
+                            ));
                         }
                     },
                 );
                 return true;
-            },
+            }
             (_, ReducedTy::Other(_)) if reduced_tys.to_fat_ptr => {
                 span_lint_and_then(
                     cx,
@@ -92,14 +101,18 @@ pub(super) fn check<'tcx>(
                     &format!("transmute to `{to_ty_orig}` which has an undefined layout"),
                     |diag| {
                         if to_ty_orig.peel_refs() != to_ty.peel_refs() {
-                            diag.note(&format!("the contained type `{to_ty}` has an undefined layout"));
+                            diag.note(&format!(
+                                "the contained type `{to_ty}` has an undefined layout"
+                            ));
                         }
                     },
                 );
                 return true;
-            },
+            }
 
-            (ReducedTy::UnorderedFields(from_ty), ReducedTy::UnorderedFields(to_ty)) if from_ty != to_ty => {
+            (ReducedTy::UnorderedFields(from_ty), ReducedTy::UnorderedFields(to_ty))
+                if from_ty != to_ty =>
+            {
                 let same_adt_did = if let (ty::Adt(from_def, from_subs), ty::Adt(to_def, to_subs))
                         = (from_ty.kind(), to_ty.kind())
                         && from_def == to_def
@@ -126,19 +139,25 @@ pub(super) fn check<'tcx>(
                             ));
                         } else {
                             if from_ty_orig.peel_refs() != from_ty {
-                                diag.note(&format!("the contained type `{from_ty}` has an undefined layout"));
+                                diag.note(&format!(
+                                    "the contained type `{from_ty}` has an undefined layout"
+                                ));
                             }
                             if to_ty_orig.peel_refs() != to_ty {
-                                diag.note(&format!("the contained type `{to_ty}` has an undefined layout"));
+                                diag.note(&format!(
+                                    "the contained type `{to_ty}` has an undefined layout"
+                                ));
                             }
                         }
                     },
                 );
                 return true;
-            },
+            }
             (
                 ReducedTy::UnorderedFields(from_ty),
-                ReducedTy::Other(_) | ReducedTy::OrderedFields(..) | ReducedTy::TypeErasure { raw_ptr_only: true },
+                ReducedTy::Other(_)
+                | ReducedTy::OrderedFields(..)
+                | ReducedTy::TypeErasure { raw_ptr_only: true },
             ) => {
                 span_lint_and_then(
                     cx,
@@ -147,14 +166,18 @@ pub(super) fn check<'tcx>(
                     &format!("transmute from `{from_ty_orig}` which has an undefined layout"),
                     |diag| {
                         if from_ty_orig.peel_refs() != from_ty {
-                            diag.note(&format!("the contained type `{from_ty}` has an undefined layout"));
+                            diag.note(&format!(
+                                "the contained type `{from_ty}` has an undefined layout"
+                            ));
                         }
                     },
                 );
                 return true;
-            },
+            }
             (
-                ReducedTy::Other(_) | ReducedTy::OrderedFields(..) | ReducedTy::TypeErasure { raw_ptr_only: true },
+                ReducedTy::Other(_)
+                | ReducedTy::OrderedFields(..)
+                | ReducedTy::TypeErasure { raw_ptr_only: true },
                 ReducedTy::UnorderedFields(to_ty),
             ) => {
                 span_lint_and_then(
@@ -164,19 +187,25 @@ pub(super) fn check<'tcx>(
                     &format!("transmute into `{to_ty_orig}` which has an undefined layout"),
                     |diag| {
                         if to_ty_orig.peel_refs() != to_ty {
-                            diag.note(&format!("the contained type `{to_ty}` has an undefined layout"));
+                            diag.note(&format!(
+                                "the contained type `{to_ty}` has an undefined layout"
+                            ));
                         }
                     },
                 );
                 return true;
-            },
+            }
             (
-                ReducedTy::OrderedFields(..) | ReducedTy::Other(_) | ReducedTy::TypeErasure { raw_ptr_only: true },
-                ReducedTy::OrderedFields(..) | ReducedTy::Other(_) | ReducedTy::TypeErasure { raw_ptr_only: true },
+                ReducedTy::OrderedFields(..)
+                | ReducedTy::Other(_)
+                | ReducedTy::TypeErasure { raw_ptr_only: true },
+                ReducedTy::OrderedFields(..)
+                | ReducedTy::Other(_)
+                | ReducedTy::TypeErasure { raw_ptr_only: true },
             )
             | (ReducedTy::UnorderedFields(_), ReducedTy::UnorderedFields(_)) => {
                 break;
-            },
+            }
         }
     }
 
@@ -194,42 +223,38 @@ struct ReducedTys<'tcx> {
 }
 
 /// Remove references so long as both types are references.
-fn reduce_refs<'tcx>(cx: &LateContext<'tcx>, mut from_ty: Ty<'tcx>, mut to_ty: Ty<'tcx>) -> ReducedTys<'tcx> {
+fn reduce_refs<'tcx>(
+    cx: &LateContext<'tcx>,
+    mut from_ty: Ty<'tcx>,
+    mut to_ty: Ty<'tcx>,
+) -> ReducedTys<'tcx> {
     let mut from_raw_ptr = false;
     let mut to_raw_ptr = false;
-    let (from_fat_ptr, to_fat_ptr) = loop {
-        break match (from_ty.kind(), to_ty.kind()) {
-            (
-                &(ty::Ref(_, from_sub_ty, _) | ty::RawPtr(TypeAndMut { ty: from_sub_ty, .. })),
-                &(ty::Ref(_, to_sub_ty, _) | ty::RawPtr(TypeAndMut { ty: to_sub_ty, .. })),
-            ) => {
-                from_raw_ptr = matches!(*from_ty.kind(), ty::RawPtr(_));
-                from_ty = from_sub_ty;
-                to_raw_ptr = matches!(*to_ty.kind(), ty::RawPtr(_));
-                to_ty = to_sub_ty;
-                continue;
-            },
-            (&(ty::Ref(_, unsized_ty, _) | ty::RawPtr(TypeAndMut { ty: unsized_ty, .. })), _)
-                if !unsized_ty.is_sized(cx.tcx.at(DUMMY_SP), cx.param_env) =>
-            {
-                (true, false)
-            },
-            (_, &(ty::Ref(_, unsized_ty, _) | ty::RawPtr(TypeAndMut { ty: unsized_ty, .. })))
-                if !unsized_ty.is_sized(cx.tcx.at(DUMMY_SP), cx.param_env) =>
-            {
-                (false, true)
-            },
-            _ => (false, false),
+    let (from_fat_ptr, to_fat_ptr) =
+        loop {
+            break match (from_ty.kind(), to_ty.kind()) {
+                (
+                    &(ty::Ref(_, from_sub_ty, _) | ty::RawPtr(TypeAndMut { ty: from_sub_ty, .. })),
+                    &(ty::Ref(_, to_sub_ty, _) | ty::RawPtr(TypeAndMut { ty: to_sub_ty, .. })),
+                ) => {
+                    from_raw_ptr = matches!(*from_ty.kind(), ty::RawPtr(_));
+                    from_ty = from_sub_ty;
+                    to_raw_ptr = matches!(*to_ty.kind(), ty::RawPtr(_));
+                    to_ty = to_sub_ty;
+                    continue;
+                }
+                (
+                    &(ty::Ref(_, unsized_ty, _) | ty::RawPtr(TypeAndMut { ty: unsized_ty, .. })),
+                    _,
+                ) if !unsized_ty.is_sized(cx.tcx, cx.param_env) => (true, false),
+                (
+                    _,
+                    &(ty::Ref(_, unsized_ty, _) | ty::RawPtr(TypeAndMut { ty: unsized_ty, .. })),
+                ) if !unsized_ty.is_sized(cx.tcx, cx.param_env) => (false, true),
+                _ => (false, false),
+            };
         };
-    };
-    ReducedTys {
-        from_ty,
-        to_ty,
-        from_raw_ptr,
-        to_raw_ptr,
-        from_fat_ptr,
-        to_fat_ptr,
-    }
+    ReducedTys { from_ty, to_ty, from_raw_ptr, to_raw_ptr, from_fat_ptr, to_fat_ptr }
 }
 
 enum ReducedTy<'tcx> {
@@ -252,11 +277,11 @@ fn reduce_ty<'tcx>(cx: &LateContext<'tcx>, mut ty: Ty<'tcx>) -> ReducedTy<'tcx>
         return match *ty.kind() {
             ty::Array(sub_ty, _) if matches!(sub_ty.kind(), ty::Int(_) | ty::Uint(_)) => {
                 ReducedTy::TypeErasure { raw_ptr_only: false }
-            },
+            }
             ty::Array(sub_ty, _) | ty::Slice(sub_ty) => {
                 ty = sub_ty;
                 continue;
-            },
+            }
             ty::Tuple(args) if args.is_empty() => ReducedTy::TypeErasure { raw_ptr_only: false },
             ty::Tuple(args) => {
                 let mut iter = args.iter();
@@ -268,7 +293,7 @@ fn reduce_ty<'tcx>(cx: &LateContext<'tcx>, mut ty: Ty<'tcx>) -> ReducedTy<'tcx>
                     continue;
                 }
                 ReducedTy::UnorderedFields(ty)
-            },
+            }
             ty::Adt(def, substs) if def.is_struct() => {
                 let mut iter = def
                     .non_enum_variant()
@@ -287,10 +312,12 @@ fn reduce_ty<'tcx>(cx: &LateContext<'tcx>, mut ty: Ty<'tcx>) -> ReducedTy<'tcx>
                 } else {
                     ReducedTy::UnorderedFields(ty)
                 }
-            },
-            ty::Adt(def, _) if def.is_enum() && (def.variants().is_empty() || is_c_void(cx, ty)) => {
+            }
+            ty::Adt(def, _)
+                if def.is_enum() && (def.variants().is_empty() || is_c_void(cx, ty)) =>
+            {
                 ReducedTy::TypeErasure { raw_ptr_only: false }
-            },
+            }
             // TODO: Check if the conversion to or from at least one of a union's fields is valid.
             ty::Adt(def, _) if def.is_union() => ReducedTy::TypeErasure { raw_ptr_only: false },
             ty::Foreign(_) | ty::Param(_) => ReducedTy::TypeErasure { raw_ptr_only: false },
@@ -329,7 +356,11 @@ fn same_except_params<'tcx>(subs1: SubstsRef<'tcx>, subs2: SubstsRef<'tcx>) -> b
     for (ty1, ty2) in subs1.types().zip(subs2.types()).filter(|(ty1, ty2)| ty1 != ty2) {
         match (ty1.kind(), ty2.kind()) {
             (ty::Param(_), _) | (_, ty::Param(_)) => (),
-            (ty::Adt(adt1, subs1), ty::Adt(adt2, subs2)) if adt1 == adt2 && same_except_params(subs1, subs2) => (),
+            (ty::Adt(adt1, subs1), ty::Adt(adt2, subs2))
+                if adt1 == adt2 && same_except_params(subs1, subs2) =>
+            {
+                ()
+            }
             _ => return false,
         }
     }
diff --git a/src/tools/clippy/clippy_lints/src/transmute/utils.rs b/src/tools/clippy/clippy_lints/src/transmute/utils.rs
index 70d166c4854c..641cdf5d330e 100644
--- a/src/tools/clippy/clippy_lints/src/transmute/utils.rs
+++ b/src/tools/clippy/clippy_lints/src/transmute/utils.rs
@@ -3,14 +3,11 @@ use rustc_hir_typeck::{cast, FnCtxt, Inherited};
 use rustc_lint::LateContext;
 use rustc_middle::ty::{cast::CastKind, Ty};
 use rustc_span::DUMMY_SP;
+use rustc_hir as hir;
 
 // check if the component types of the transmuted collection and the result have different ABI,
 // size or alignment
-pub(super) fn is_layout_incompatible<'tcx>(
-    cx: &LateContext<'tcx>,
-    from: Ty<'tcx>,
-    to: Ty<'tcx>,
-) -> bool {
+pub(super) fn is_layout_incompatible<'tcx>(cx: &LateContext<'tcx>, from: Ty<'tcx>, to: Ty<'tcx>) -> bool {
     if let Ok(from) = cx.tcx.try_normalize_erasing_regions(cx.param_env, from)
         && let Ok(to) = cx.tcx.try_normalize_erasing_regions(cx.param_env, to)
         && let Ok(from_layout) = cx.tcx.layout_of(cx.param_env.and(from))
@@ -33,9 +30,7 @@ pub(super) fn can_be_expressed_as_pointer_cast<'tcx>(
     from_ty: Ty<'tcx>,
     to_ty: Ty<'tcx>,
 ) -> bool {
-    use CastKind::{
-        AddrPtrCast, ArrayPtrCast, FnPtrAddrCast, FnPtrPtrCast, PtrAddrCast, PtrPtrCast,
-    };
+    use CastKind::{AddrPtrCast, ArrayPtrCast, FnPtrAddrCast, FnPtrPtrCast, PtrAddrCast, PtrPtrCast};
     matches!(
         check_cast(cx, e, from_ty, to_ty),
         Some(PtrPtrCast | PtrAddrCast | AddrPtrCast | ArrayPtrCast | FnPtrPtrCast | FnPtrAddrCast)
@@ -46,25 +41,23 @@ pub(super) fn can_be_expressed_as_pointer_cast<'tcx>(
 /// the cast. In certain cases, including some invalid casts from array references
 /// to pointers, this may cause additional errors to be emitted and/or ICE error
 /// messages. This function will panic if that occurs.
-fn check_cast<'tcx>(
-    cx: &LateContext<'tcx>,
-    e: &'tcx Expr<'_>,
-    from_ty: Ty<'tcx>,
-    to_ty: Ty<'tcx>,
-) -> Option<CastKind> {
+fn check_cast<'tcx>(cx: &LateContext<'tcx>, e: &'tcx Expr<'_>, from_ty: Ty<'tcx>, to_ty: Ty<'tcx>) -> Option<CastKind> {
     let hir_id = e.hir_id;
     let local_def_id = hir_id.owner.def_id;
 
     Inherited::build(cx.tcx, local_def_id).enter(|inherited| {
-        let fn_ctxt = FnCtxt::new(&inherited, cx.param_env, hir_id);
+        let fn_ctxt = FnCtxt::new(inherited, cx.param_env, hir_id);
 
         // If we already have errors, we can't be sure we can pointer cast.
-        assert!(!fn_ctxt.errors_reported_since_creation(), "Newly created FnCtxt contained errors");
+        assert!(
+            !fn_ctxt.errors_reported_since_creation(),
+            "Newly created FnCtxt contained errors"
+        );
 
         if let Ok(check) = cast::CastCheck::new(
             &fn_ctxt, e, from_ty, to_ty,
             // We won't show any error to the user, so we don't care what the span is here.
-            DUMMY_SP, DUMMY_SP,
+            DUMMY_SP, DUMMY_SP, hir::Constness::NotConst,
         ) {
             let res = check.do_check(&fn_ctxt);
 
diff --git a/src/tools/clippy/clippy_lints/src/types/mod.rs b/src/tools/clippy/clippy_lints/src/types/mod.rs
index a06d1fffd8bd..f6de87b0526c 100644
--- a/src/tools/clippy/clippy_lints/src/types/mod.rs
+++ b/src/tools/clippy/clippy_lints/src/types/mod.rs
@@ -319,7 +319,7 @@ impl<'tcx> LateLintPass<'tcx> for Types {
                 false
             };
 
-        let is_exported = cx.access_levels.is_exported(cx.tcx.hir().local_def_id(id));
+        let is_exported = cx.effective_visibilities.is_exported(cx.tcx.hir().local_def_id(id));
 
         self.check_fn_decl(
             cx,
@@ -333,7 +333,7 @@ impl<'tcx> LateLintPass<'tcx> for Types {
     }
 
     fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'_>) {
-        let is_exported = cx.access_levels.is_exported(item.def_id.def_id);
+        let is_exported = cx.effective_visibilities.is_exported(item.owner_id.def_id);
 
         match item.kind {
             ItemKind::Static(ty, _, _) | ItemKind::Const(ty, _) => self.check_ty(
@@ -379,7 +379,7 @@ impl<'tcx> LateLintPass<'tcx> for Types {
     }
 
     fn check_field_def(&mut self, cx: &LateContext<'_>, field: &hir::FieldDef<'_>) {
-        let is_exported = cx.access_levels.is_exported(cx.tcx.hir().local_def_id(field.hir_id));
+        let is_exported = cx.effective_visibilities.is_exported(cx.tcx.hir().local_def_id(field.hir_id));
 
         self.check_ty(
             cx,
@@ -392,7 +392,7 @@ impl<'tcx> LateLintPass<'tcx> for Types {
     }
 
     fn check_trait_item(&mut self, cx: &LateContext<'tcx>, item: &TraitItem<'_>) {
-        let is_exported = cx.access_levels.is_exported(item.def_id.def_id);
+        let is_exported = cx.effective_visibilities.is_exported(item.owner_id.def_id);
 
         let context = CheckTyContext {
             is_exported,
diff --git a/src/tools/clippy/clippy_lints/src/types/rc_buffer.rs b/src/tools/clippy/clippy_lints/src/types/rc_buffer.rs
index 6b9de64e24c9..fa567b9b2d24 100644
--- a/src/tools/clippy/clippy_lints/src/types/rc_buffer.rs
+++ b/src/tools/clippy/clippy_lints/src/types/rc_buffer.rs
@@ -9,6 +9,7 @@ use rustc_span::symbol::sym;
 use super::RC_BUFFER;
 
 pub(super) fn check(cx: &LateContext<'_>, hir_ty: &hir::Ty<'_>, qpath: &QPath<'_>, def_id: DefId) -> bool {
+    let app = Applicability::Unspecified;
     if cx.tcx.is_diagnostic_item(sym::Rc, def_id) {
         if let Some(alternate) = match_buffer_type(cx, qpath) {
             span_lint_and_sugg(
@@ -18,7 +19,7 @@ pub(super) fn check(cx: &LateContext<'_>, hir_ty: &hir::Ty<'_>, qpath: &QPath<'_
                 "usage of `Rc<T>` when T is a buffer type",
                 "try",
                 format!("Rc<{alternate}>"),
-                Applicability::MachineApplicable,
+                app,
             );
         } else {
             let Some(ty) = qpath_generic_tys(qpath).next() else { return false };
@@ -26,15 +27,12 @@ pub(super) fn check(cx: &LateContext<'_>, hir_ty: &hir::Ty<'_>, qpath: &QPath<'_
             if !cx.tcx.is_diagnostic_item(sym::Vec, id) {
                 return false;
             }
-            let qpath = match &ty.kind {
-                TyKind::Path(qpath) => qpath,
-                _ => return false,
-            };
+            let TyKind::Path(qpath) = &ty.kind else { return false };
             let inner_span = match qpath_generic_tys(qpath).next() {
                 Some(ty) => ty.span,
                 None => return false,
             };
-            let mut applicability = Applicability::MachineApplicable;
+            let mut applicability = app;
             span_lint_and_sugg(
                 cx,
                 RC_BUFFER,
@@ -45,7 +43,7 @@ pub(super) fn check(cx: &LateContext<'_>, hir_ty: &hir::Ty<'_>, qpath: &QPath<'_
                     "Rc<[{}]>",
                     snippet_with_applicability(cx, inner_span, "..", &mut applicability)
                 ),
-                Applicability::MachineApplicable,
+                app,
             );
             return true;
         }
@@ -58,22 +56,19 @@ pub(super) fn check(cx: &LateContext<'_>, hir_ty: &hir::Ty<'_>, qpath: &QPath<'_
                 "usage of `Arc<T>` when T is a buffer type",
                 "try",
                 format!("Arc<{alternate}>"),
-                Applicability::MachineApplicable,
+                app,
             );
         } else if let Some(ty) = qpath_generic_tys(qpath).next() {
             let Some(id) = path_def_id(cx, ty) else { return false };
             if !cx.tcx.is_diagnostic_item(sym::Vec, id) {
                 return false;
             }
-            let qpath = match &ty.kind {
-                TyKind::Path(qpath) => qpath,
-                _ => return false,
-            };
+            let TyKind::Path(qpath) = &ty.kind else { return false };
             let inner_span = match qpath_generic_tys(qpath).next() {
                 Some(ty) => ty.span,
                 None => return false,
             };
-            let mut applicability = Applicability::MachineApplicable;
+            let mut applicability = app;
             span_lint_and_sugg(
                 cx,
                 RC_BUFFER,
@@ -84,7 +79,7 @@ pub(super) fn check(cx: &LateContext<'_>, hir_ty: &hir::Ty<'_>, qpath: &QPath<'_
                     "Arc<[{}]>",
                     snippet_with_applicability(cx, inner_span, "..", &mut applicability)
                 ),
-                Applicability::MachineApplicable,
+                app,
             );
             return true;
         }
diff --git a/src/tools/clippy/clippy_lints/src/types/redundant_allocation.rs b/src/tools/clippy/clippy_lints/src/types/redundant_allocation.rs
index ecb672005390..2b964b64a330 100644
--- a/src/tools/clippy/clippy_lints/src/types/redundant_allocation.rs
+++ b/src/tools/clippy/clippy_lints/src/types/redundant_allocation.rs
@@ -9,7 +9,13 @@ use rustc_span::symbol::sym;
 
 use super::{utils, REDUNDANT_ALLOCATION};
 
-pub(super) fn check(cx: &LateContext<'_>, hir_ty: &hir::Ty<'_>, qpath: &QPath<'_>, def_id: DefId) -> bool {
+pub(super) fn check(
+    cx: &LateContext<'_>,
+    hir_ty: &hir::Ty<'_>,
+    qpath: &QPath<'_>,
+    def_id: DefId,
+) -> bool {
+    let mut applicability = Applicability::MaybeIncorrect;
     let outer_sym = if Some(def_id) == cx.tcx.lang_items().owned_box() {
         "Box"
     } else if cx.tcx.is_diagnostic_item(sym::Rc, def_id) {
@@ -21,7 +27,6 @@ pub(super) fn check(cx: &LateContext<'_>, hir_ty: &hir::Ty<'_>, qpath: &QPath<'_
     };
 
     if let Some(span) = utils::match_borrows_parameter(cx, qpath) {
-        let mut applicability = Applicability::MaybeIncorrect;
         let generic_snippet = snippet_with_applicability(cx, span, "..", &mut applicability);
         span_lint_and_then(
             cx,
@@ -29,7 +34,12 @@ pub(super) fn check(cx: &LateContext<'_>, hir_ty: &hir::Ty<'_>, qpath: &QPath<'_
             hir_ty.span,
             &format!("usage of `{outer_sym}<{generic_snippet}>`"),
             |diag| {
-                diag.span_suggestion(hir_ty.span, "try", format!("{generic_snippet}"), applicability);
+                diag.span_suggestion(
+                    hir_ty.span,
+                    "try",
+                    format!("{generic_snippet}"),
+                    applicability,
+                );
                 diag.note(&format!(
                     "`{generic_snippet}` is already a pointer, `{outer_sym}<{generic_snippet}>` allocates a pointer on the heap"
                 ));
@@ -47,24 +57,22 @@ pub(super) fn check(cx: &LateContext<'_>, hir_ty: &hir::Ty<'_>, qpath: &QPath<'_
         _ => return false,
     };
 
-    let inner_qpath = match &ty.kind {
-        TyKind::Path(inner_qpath) => inner_qpath,
-        _ => return false,
+    let TyKind::Path(inner_qpath) = &ty.kind else {
+        return false
     };
     let inner_span = match qpath_generic_tys(inner_qpath).next() {
         Some(ty) => {
             // Reallocation of a fat pointer causes it to become thin. `hir_ty_to_ty` is safe to use
             // here because `mod.rs` guarantees this lint is only run on types outside of bodies and
             // is not run on locals.
-            if !hir_ty_to_ty(cx.tcx, ty).is_sized(cx.tcx.at(ty.span), cx.param_env) {
+            if !hir_ty_to_ty(cx.tcx, ty).is_sized(cx.tcx, cx.param_env) {
                 return false;
             }
             ty.span
-        },
+        }
         None => return false,
     };
     if inner_sym == outer_sym {
-        let mut applicability = Applicability::MaybeIncorrect;
         let generic_snippet = snippet_with_applicability(cx, inner_span, "..", &mut applicability);
         span_lint_and_then(
             cx,
diff --git a/src/tools/clippy/clippy_lints/src/types/vec_box.rs b/src/tools/clippy/clippy_lints/src/types/vec_box.rs
index 6c329d8cdf19..9ad2cb853d39 100644
--- a/src/tools/clippy/clippy_lints/src/types/vec_box.rs
+++ b/src/tools/clippy/clippy_lints/src/types/vec_box.rs
@@ -40,7 +40,7 @@ pub(super) fn check(
             });
             let ty_ty = hir_ty_to_ty(cx.tcx, boxed_ty);
             if !ty_ty.has_escaping_bound_vars();
-            if ty_ty.is_sized(cx.tcx.at(ty.span), cx.param_env);
+            if ty_ty.is_sized(cx.tcx, cx.param_env);
             if let Ok(ty_ty_size) = cx.layout_of(ty_ty).map(|l| l.size.bytes());
             if ty_ty_size <= box_size_threshold;
             then {
diff --git a/src/tools/clippy/clippy_lints/src/unit_return_expecting_ord.rs b/src/tools/clippy/clippy_lints/src/unit_return_expecting_ord.rs
index 57aff5367dd1..1307288623f9 100644
--- a/src/tools/clippy/clippy_lints/src/unit_return_expecting_ord.rs
+++ b/src/tools/clippy/clippy_lints/src/unit_return_expecting_ord.rs
@@ -1,5 +1,4 @@
 use clippy_utils::diagnostics::{span_lint, span_lint_and_help};
-use clippy_utils::{get_trait_def_id, paths};
 use if_chain::if_chain;
 use rustc_hir::def_id::DefId;
 use rustc_hir::{Closure, Expr, ExprKind, StmtKind};
@@ -7,7 +6,7 @@ use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::ty;
 use rustc_middle::ty::{GenericPredicates, PredicateKind, ProjectionPredicate, TraitPredicate};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
-use rustc_span::{BytePos, Span};
+use rustc_span::{sym, BytePos, Span};
 
 declare_clippy_lint! {
     /// ### What it does
@@ -80,7 +79,7 @@ fn get_args_to_check<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) -> Ve
         let fn_sig = cx.tcx.fn_sig(def_id);
         let generics = cx.tcx.predicates_of(def_id);
         let fn_mut_preds = get_trait_predicates_for_trait_id(cx, generics, cx.tcx.lang_items().fn_mut_trait());
-        let ord_preds = get_trait_predicates_for_trait_id(cx, generics, get_trait_def_id(cx, &paths::ORD));
+        let ord_preds = get_trait_predicates_for_trait_id(cx, generics, cx.tcx.get_diagnostic_item(sym::Ord));
         let partial_ord_preds =
             get_trait_predicates_for_trait_id(cx, generics, cx.tcx.lang_items().partial_ord_trait());
         // Trying to call erase_late_bound_regions on fn_sig.inputs() gives the following error
@@ -99,11 +98,15 @@ fn get_args_to_check<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) -> Ve
                         if trait_pred.self_ty() == inp;
                         if let Some(return_ty_pred) = get_projection_pred(cx, generics, *trait_pred);
                         then {
-                            if ord_preds.iter().any(|ord| Some(ord.self_ty()) == return_ty_pred.term.ty()) {
+                            if ord_preds
+                                .iter()
+                                .any(|ord| Some(ord.self_ty()) == return_ty_pred.term.ty())
+                            {
                                 args_to_check.push((i, "Ord".to_string()));
-                            } else if partial_ord_preds.iter().any(|pord| {
-                                pord.self_ty() == return_ty_pred.term.ty().unwrap()
-                            }) {
+                            } else if partial_ord_preds
+                                .iter()
+                                .any(|pord| pord.self_ty() == return_ty_pred.term.ty().unwrap())
+                            {
                                 args_to_check.push((i, "PartialOrd".to_string()));
                             }
                         }
diff --git a/src/tools/clippy/clippy_lints/src/unnecessary_owned_empty_strings.rs b/src/tools/clippy/clippy_lints/src/unnecessary_owned_empty_strings.rs
index 016aacbf9da3..ab73f0fc44f4 100644
--- a/src/tools/clippy/clippy_lints/src/unnecessary_owned_empty_strings.rs
+++ b/src/tools/clippy/clippy_lints/src/unnecessary_owned_empty_strings.rs
@@ -3,7 +3,7 @@ use clippy_utils::{match_def_path, paths};
 use if_chain::if_chain;
 use rustc_ast::ast::LitKind;
 use rustc_errors::Applicability;
-use rustc_hir::{BorrowKind, Expr, ExprKind, LangItem, Mutability};
+use rustc_hir::{BorrowKind, Expr, ExprKind, Mutability};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::ty;
 use rustc_session::{declare_lint_pass, declare_tool_lint};
@@ -55,7 +55,7 @@ impl<'tcx> LateLintPass<'tcx> for UnnecessaryOwnedEmptyStrings {
                         );
                 } else {
                     if_chain! {
-                        if cx.tcx.lang_items().require(LangItem::FromFrom).ok() == Some(fun_def_id);
+                        if Some(fun_def_id) == cx.tcx.lang_items().from_fn();
                         if let [.., last_arg] = args;
                         if let ExprKind::Lit(spanned) = &last_arg.kind;
                         if let LitKind::Str(symbol, _) = spanned.node;
diff --git a/src/tools/clippy/clippy_lints/src/unnecessary_wraps.rs b/src/tools/clippy/clippy_lints/src/unnecessary_wraps.rs
index 7211e6864f3a..60b46854b4ff 100644
--- a/src/tools/clippy/clippy_lints/src/unnecessary_wraps.rs
+++ b/src/tools/clippy/clippy_lints/src/unnecessary_wraps.rs
@@ -83,7 +83,7 @@ impl<'tcx> LateLintPass<'tcx> for UnnecessaryWraps {
         match fn_kind {
             FnKind::ItemFn(..) | FnKind::Method(..) => {
                 let def_id = cx.tcx.hir().local_def_id(hir_id);
-                if self.avoid_breaking_exported_api && cx.access_levels.is_exported(def_id) {
+                if self.avoid_breaking_exported_api && cx.effective_visibilities.is_exported(def_id) {
                     return;
                 }
             },
diff --git a/src/tools/clippy/clippy_lints/src/unnested_or_patterns.rs b/src/tools/clippy/clippy_lints/src/unnested_or_patterns.rs
index fb73c386640b..b305dae76084 100644
--- a/src/tools/clippy/clippy_lints/src/unnested_or_patterns.rs
+++ b/src/tools/clippy/clippy_lints/src/unnested_or_patterns.rs
@@ -163,9 +163,8 @@ fn unnest_or_patterns(pat: &mut P<Pat>) -> bool {
             noop_visit_pat(p, self);
 
             // Don't have an or-pattern? Just quit early on.
-            let alternatives = match &mut p.kind {
-                Or(ps) => ps,
-                _ => return,
+            let Or(alternatives) = &mut p.kind else {
+                return
             };
 
             // Collapse or-patterns directly nested in or-patterns.
diff --git a/src/tools/clippy/clippy_lints/src/unused_io_amount.rs b/src/tools/clippy/clippy_lints/src/unused_io_amount.rs
index 8bcdff66331d..92053cec59fc 100644
--- a/src/tools/clippy/clippy_lints/src/unused_io_amount.rs
+++ b/src/tools/clippy/clippy_lints/src/unused_io_amount.rs
@@ -47,9 +47,8 @@ declare_lint_pass!(UnusedIoAmount => [UNUSED_IO_AMOUNT]);
 
 impl<'tcx> LateLintPass<'tcx> for UnusedIoAmount {
     fn check_stmt(&mut self, cx: &LateContext<'_>, s: &hir::Stmt<'_>) {
-        let expr = match s.kind {
-            hir::StmtKind::Semi(expr) | hir::StmtKind::Expr(expr) => expr,
-            _ => return,
+        let (hir::StmtKind::Semi(expr) | hir::StmtKind::Expr(expr)) = s.kind else {
+            return
         };
 
         match expr.kind {
diff --git a/src/tools/clippy/clippy_lints/src/unused_peekable.rs b/src/tools/clippy/clippy_lints/src/unused_peekable.rs
index f1cebf0f9923..b452be084094 100644
--- a/src/tools/clippy/clippy_lints/src/unused_peekable.rs
+++ b/src/tools/clippy/clippy_lints/src/unused_peekable.rs
@@ -3,7 +3,6 @@ use clippy_utils::ty::{match_type, peel_mid_ty_refs_is_mutable};
 use clippy_utils::{fn_def_id, is_trait_method, path_to_local_id, paths, peel_ref_operators};
 use rustc_ast::Mutability;
 use rustc_hir::intravisit::{walk_expr, Visitor};
-use rustc_hir::lang_items::LangItem;
 use rustc_hir::{Block, Expr, ExprKind, HirId, Local, Node, PatKind, PathSegment, StmtKind};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::hir::nested_filter::OnlyBodies;
@@ -132,11 +131,11 @@ impl<'tcx> Visitor<'tcx> for PeekableVisitor<'_, 'tcx> {
                             // If the Peekable is passed to a function, stop
                             ExprKind::Call(_, args) => {
                                 if let Some(func_did) = fn_def_id(self.cx, expr)
-                                    && let Ok(into_iter_did) = self
+                                    && let Some(into_iter_did) = self
                                         .cx
                                         .tcx
                                         .lang_items()
-                                        .require(LangItem::IntoIterIntoIter)
+                                        .into_iter_fn()
                                     && func_did == into_iter_did
                                 {
                                     // Probably a for loop desugar, stop searching
diff --git a/src/tools/clippy/clippy_lints/src/unused_self.rs b/src/tools/clippy/clippy_lints/src/unused_self.rs
index 713fe06bad43..42bccc7212b3 100644
--- a/src/tools/clippy/clippy_lints/src/unused_self.rs
+++ b/src/tools/clippy/clippy_lints/src/unused_self.rs
@@ -56,12 +56,12 @@ impl<'tcx> LateLintPass<'tcx> for UnusedSelf {
         }
         let parent = cx.tcx.hir().get_parent_item(impl_item.hir_id()).def_id;
         let parent_item = cx.tcx.hir().expect_item(parent);
-        let assoc_item = cx.tcx.associated_item(impl_item.def_id);
+        let assoc_item = cx.tcx.associated_item(impl_item.owner_id);
         if_chain! {
             if let ItemKind::Impl(Impl { of_trait: None, .. }) = parent_item.kind;
             if assoc_item.fn_has_self_parameter;
             if let ImplItemKind::Fn(.., body_id) = &impl_item.kind;
-            if !cx.access_levels.is_exported(impl_item.def_id.def_id) || !self.avoid_breaking_exported_api;
+            if !cx.effective_visibilities.is_exported(impl_item.owner_id.def_id) || !self.avoid_breaking_exported_api;
             let body = cx.tcx.hir().body(*body_id);
             if let [self_param, ..] = body.params;
             if !is_local_used(cx, body, self_param.pat.hir_id);
diff --git a/src/tools/clippy/clippy_lints/src/unwrap_in_result.rs b/src/tools/clippy/clippy_lints/src/unwrap_in_result.rs
index a69719b127b2..f3611d174340 100644
--- a/src/tools/clippy/clippy_lints/src/unwrap_in_result.rs
+++ b/src/tools/clippy/clippy_lints/src/unwrap_in_result.rs
@@ -76,7 +76,7 @@ impl<'tcx> LateLintPass<'tcx> for UnwrapInResult {
 fn lint_impl_body<'tcx>(cx: &LateContext<'tcx>, impl_span: Span, impl_item: &'tcx hir::ImplItem<'_>) {
     if let ImplItemKind::Fn(_, body_id) = impl_item.kind {
         let body = cx.tcx.hir().body(body_id);
-        let typeck = cx.tcx.typeck(impl_item.def_id.def_id);
+        let typeck = cx.tcx.typeck(impl_item.owner_id.def_id);
         let mut result = Vec::new();
         let _: Option<!> = for_each_expr(body.value, |e| {
             // check for `expect`
diff --git a/src/tools/clippy/clippy_lints/src/upper_case_acronyms.rs b/src/tools/clippy/clippy_lints/src/upper_case_acronyms.rs
index 654ea306793b..1d2d3eb12e11 100644
--- a/src/tools/clippy/clippy_lints/src/upper_case_acronyms.rs
+++ b/src/tools/clippy/clippy_lints/src/upper_case_acronyms.rs
@@ -105,7 +105,7 @@ impl LateLintPass<'_> for UpperCaseAcronyms {
     fn check_item(&mut self, cx: &LateContext<'_>, it: &Item<'_>) {
         // do not lint public items or in macros
         if in_external_macro(cx.sess(), it.span)
-            || (self.avoid_breaking_exported_api && cx.access_levels.is_exported(it.def_id.def_id))
+            || (self.avoid_breaking_exported_api && cx.effective_visibilities.is_exported(it.owner_id.def_id))
         {
             return;
         }
diff --git a/src/tools/clippy/clippy_lints/src/use_self.rs b/src/tools/clippy/clippy_lints/src/use_self.rs
index 65f1b5462081..c6cdf3f85fc3 100644
--- a/src/tools/clippy/clippy_lints/src/use_self.rs
+++ b/src/tools/clippy/clippy_lints/src/use_self.rs
@@ -106,7 +106,7 @@ impl<'tcx> LateLintPass<'tcx> for UseSelf {
             if !is_from_proc_macro(cx, item); // expensive, should be last check
             then {
                 StackItem::Check {
-                    impl_id: item.def_id.def_id,
+                    impl_id: item.owner_id.def_id,
                     in_body: 0,
                     types_to_skip: std::iter::once(self_ty.hir_id).collect(),
                 }
@@ -143,7 +143,7 @@ impl<'tcx> LateLintPass<'tcx> for UseSelf {
                 // trait, not in the impl of the trait.
                 let trait_method = cx
                     .tcx
-                    .associated_item(impl_item.def_id)
+                    .associated_item(impl_item.owner_id)
                     .trait_item_def_id
                     .expect("impl method matches a trait method");
                 let trait_method_sig = cx.tcx.fn_sig(trait_method);
diff --git a/src/tools/clippy/clippy_lints/src/useless_conversion.rs b/src/tools/clippy/clippy_lints/src/useless_conversion.rs
index a82643a59f97..3743d5d97a73 100644
--- a/src/tools/clippy/clippy_lints/src/useless_conversion.rs
+++ b/src/tools/clippy/clippy_lints/src/useless_conversion.rs
@@ -5,7 +5,7 @@ use clippy_utils::ty::{is_type_diagnostic_item, same_type_and_consts};
 use clippy_utils::{get_parent_expr, is_trait_method, match_def_path, paths};
 use if_chain::if_chain;
 use rustc_errors::Applicability;
-use rustc_hir::{Expr, ExprKind, HirId, LangItem, MatchSource};
+use rustc_hir::{Expr, ExprKind, HirId, MatchSource};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::ty;
 use rustc_session::{declare_tool_lint, impl_lint_pass};
@@ -55,9 +55,8 @@ impl<'tcx> LateLintPass<'tcx> for UselessConversion {
 
         match e.kind {
             ExprKind::Match(_, arms, MatchSource::TryDesugar) => {
-                let e = match arms[0].body.kind {
-                    ExprKind::Ret(Some(e)) | ExprKind::Break(_, Some(e)) => e,
-                    _ => return,
+                let (ExprKind::Ret(Some(e)) | ExprKind::Break(_, Some(e))) = arms[0].body.kind else {
+                     return
                 };
                 if let ExprKind::Call(_, [arg, ..]) = e.kind {
                     self.try_desugar_arm.push(arg.hir_id);
@@ -154,7 +153,7 @@ impl<'tcx> LateLintPass<'tcx> for UselessConversion {
                         }
 
                         if_chain! {
-                            if cx.tcx.lang_items().require(LangItem::FromFrom).ok() == Some(def_id);
+                            if Some(def_id) == cx.tcx.lang_items().from_fn();
                             if same_type_and_consts(a, b);
 
                             then {
diff --git a/src/tools/clippy/clippy_lints/src/utils/author.rs b/src/tools/clippy/clippy_lints/src/utils/author.rs
index e069de8cb5c7..0c052d86eda4 100644
--- a/src/tools/clippy/clippy_lints/src/utils/author.rs
+++ b/src/tools/clippy/clippy_lints/src/utils/author.rs
@@ -12,6 +12,7 @@ use rustc_hir::{
 use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 use rustc_span::symbol::{Ident, Symbol};
+use std::cell::Cell;
 use std::fmt::{Display, Formatter, Write as _};
 
 declare_clippy_lint! {
@@ -37,15 +38,13 @@ declare_clippy_lint! {
     ///
     /// ```rust,ignore
     /// // ./tests/ui/new_lint.stdout
-    /// if_chain! {
-    ///     if let ExprKind::If(ref cond, ref then, None) = item.kind,
-    ///     if let ExprKind::Binary(BinOp::Eq, ref left, ref right) = cond.kind,
-    ///     if let ExprKind::Path(ref path) = left.kind,
-    ///     if let ExprKind::Lit(ref lit) = right.kind,
-    ///     if let LitKind::Int(42, _) = lit.node,
-    ///     then {
-    ///         // report your lint here
-    ///     }
+    /// if ExprKind::If(ref cond, ref then, None) = item.kind
+    ///     && let ExprKind::Binary(BinOp::Eq, ref left, ref right) = cond.kind
+    ///     && let ExprKind::Path(ref path) = left.kind
+    ///     && let ExprKind::Lit(ref lit) = right.kind
+    ///     && let LitKind::Int(42, _) = lit.node
+    /// {
+    ///     // report your lint here
     /// }
     /// ```
     pub LINT_AUTHOR,
@@ -91,15 +90,16 @@ macro_rules! field {
     };
 }
 
-fn prelude() {
-    println!("if_chain! {{");
-}
-
-fn done() {
-    println!("    then {{");
-    println!("        // report your lint here");
-    println!("    }}");
-    println!("}}");
+/// Print a condition of a let chain, `chain!(self, "let Some(x) = y")` will print
+/// `if let Some(x) = y` on the first call and `    && let Some(x) = y` thereafter
+macro_rules! chain {
+    ($self:ident, $($t:tt)*) => {
+        if $self.first.take() {
+            println!("if {}", format_args!($($t)*));
+        } else {
+            println!("    && {}", format_args!($($t)*));
+        }
+    }
 }
 
 impl<'tcx> LateLintPass<'tcx> for Author {
@@ -149,9 +149,10 @@ fn check_item(cx: &LateContext<'_>, hir_id: HirId) {
 
 fn check_node(cx: &LateContext<'_>, hir_id: HirId, f: impl Fn(&PrintVisitor<'_, '_>)) {
     if has_attr(cx, hir_id) {
-        prelude();
         f(&PrintVisitor::new(cx));
-        done();
+        println!("{{");
+        println!("    // report your lint here");
+        println!("}}");
     }
 }
 
@@ -195,7 +196,9 @@ struct PrintVisitor<'a, 'tcx> {
     cx: &'a LateContext<'tcx>,
     /// Fields are the current index that needs to be appended to pattern
     /// binding names
-    ids: std::cell::Cell<FxHashMap<&'static str, u32>>,
+    ids: Cell<FxHashMap<&'static str, u32>>,
+    /// Currently at the first condition in the if chain
+    first: Cell<bool>,
 }
 
 #[allow(clippy::unused_self)]
@@ -203,7 +206,8 @@ impl<'a, 'tcx> PrintVisitor<'a, 'tcx> {
     fn new(cx: &'a LateContext<'tcx>) -> Self {
         Self {
             cx,
-            ids: std::cell::Cell::default(),
+            ids: Cell::default(),
+            first: Cell::new(true),
         }
     }
 
@@ -226,10 +230,10 @@ impl<'a, 'tcx> PrintVisitor<'a, 'tcx> {
 
     fn option<T: Copy>(&self, option: &Binding<Option<T>>, name: &'static str, f: impl Fn(&Binding<T>)) {
         match option.value {
-            None => out!("if {option}.is_none();"),
+            None => chain!(self, "{option}.is_none()"),
             Some(value) => {
                 let value = &self.bind(name, value);
-                out!("if let Some({value}) = {option};");
+                chain!(self, "let Some({value}) = {option}");
                 f(value);
             },
         }
@@ -237,9 +241,9 @@ impl<'a, 'tcx> PrintVisitor<'a, 'tcx> {
 
     fn slice<T>(&self, slice: &Binding<&[T]>, f: impl Fn(&Binding<&T>)) {
         if slice.value.is_empty() {
-            out!("if {slice}.is_empty();");
+            chain!(self, "{slice}.is_empty()");
         } else {
-            out!("if {slice}.len() == {};", slice.value.len());
+            chain!(self, "{slice}.len() == {}", slice.value.len());
             for (i, value) in slice.value.iter().enumerate() {
                 let name = format!("{slice}[{i}]");
                 f(&Binding { name, value });
@@ -254,23 +258,23 @@ impl<'a, 'tcx> PrintVisitor<'a, 'tcx> {
     }
 
     fn ident(&self, ident: &Binding<Ident>) {
-        out!("if {ident}.as_str() == {:?};", ident.value.as_str());
+        chain!(self, "{ident}.as_str() == {:?}", ident.value.as_str());
     }
 
     fn symbol(&self, symbol: &Binding<Symbol>) {
-        out!("if {symbol}.as_str() == {:?};", symbol.value.as_str());
+        chain!(self, "{symbol}.as_str() == {:?}", symbol.value.as_str());
     }
 
     fn qpath(&self, qpath: &Binding<&QPath<'_>>) {
         if let QPath::LangItem(lang_item, ..) = *qpath.value {
-            out!("if matches!({qpath}, QPath::LangItem(LangItem::{lang_item:?}, _));");
+            chain!(self, "matches!({qpath}, QPath::LangItem(LangItem::{lang_item:?}, _))");
         } else {
-            out!("if match_qpath({qpath}, &[{}]);", path_to_string(qpath.value));
+            chain!(self, "match_qpath({qpath}, &[{}])", path_to_string(qpath.value));
         }
     }
 
     fn lit(&self, lit: &Binding<&Lit>) {
-        let kind = |kind| out!("if let LitKind::{kind} = {lit}.node;");
+        let kind = |kind| chain!(self, "let LitKind::{kind} = {lit}.node");
         macro_rules! kind {
             ($($t:tt)*) => (kind(format_args!($($t)*)));
         }
@@ -298,7 +302,7 @@ impl<'a, 'tcx> PrintVisitor<'a, 'tcx> {
             LitKind::ByteStr(ref vec) => {
                 bind!(self, vec);
                 kind!("ByteStr(ref {vec})");
-                out!("if let [{:?}] = **{vec};", vec.value);
+                chain!(self, "let [{:?}] = **{vec}", vec.value);
             },
             LitKind::Str(s, _) => {
                 bind!(self, s);
@@ -311,15 +315,15 @@ impl<'a, 'tcx> PrintVisitor<'a, 'tcx> {
     fn arm(&self, arm: &Binding<&hir::Arm<'_>>) {
         self.pat(field!(arm.pat));
         match arm.value.guard {
-            None => out!("if {arm}.guard.is_none();"),
+            None => chain!(self, "{arm}.guard.is_none()"),
             Some(hir::Guard::If(expr)) => {
                 bind!(self, expr);
-                out!("if let Some(Guard::If({expr})) = {arm}.guard;");
+                chain!(self, "let Some(Guard::If({expr})) = {arm}.guard");
                 self.expr(expr);
             },
             Some(hir::Guard::IfLet(let_expr)) => {
                 bind!(self, let_expr);
-                out!("if let Some(Guard::IfLet({let_expr}) = {arm}.guard;");
+                chain!(self, "let Some(Guard::IfLet({let_expr}) = {arm}.guard");
                 self.pat(field!(let_expr.pat));
                 self.expr(field!(let_expr.init));
             },
@@ -331,9 +335,10 @@ impl<'a, 'tcx> PrintVisitor<'a, 'tcx> {
     fn expr(&self, expr: &Binding<&hir::Expr<'_>>) {
         if let Some(higher::While { condition, body }) = higher::While::hir(expr.value) {
             bind!(self, condition, body);
-            out!(
-                "if let Some(higher::While {{ condition: {condition}, body: {body} }}) \
-                = higher::While::hir({expr});"
+            chain!(
+                self,
+                "let Some(higher::While {{ condition: {condition}, body: {body} }}) \
+                = higher::While::hir({expr})"
             );
             self.expr(condition);
             self.expr(body);
@@ -347,9 +352,10 @@ impl<'a, 'tcx> PrintVisitor<'a, 'tcx> {
         }) = higher::WhileLet::hir(expr.value)
         {
             bind!(self, let_pat, let_expr, if_then);
-            out!(
-                "if let Some(higher::WhileLet {{ let_pat: {let_pat}, let_expr: {let_expr}, if_then: {if_then} }}) \
-                = higher::WhileLet::hir({expr});"
+            chain!(
+                self,
+                "let Some(higher::WhileLet {{ let_pat: {let_pat}, let_expr: {let_expr}, if_then: {if_then} }}) \
+                = higher::WhileLet::hir({expr})"
             );
             self.pat(let_pat);
             self.expr(let_expr);
@@ -359,9 +365,10 @@ impl<'a, 'tcx> PrintVisitor<'a, 'tcx> {
 
         if let Some(higher::ForLoop { pat, arg, body, .. }) = higher::ForLoop::hir(expr.value) {
             bind!(self, pat, arg, body);
-            out!(
-                "if let Some(higher::ForLoop {{ pat: {pat}, arg: {arg}, body: {body}, .. }}) \
-                = higher::ForLoop::hir({expr});"
+            chain!(
+                self,
+                "let Some(higher::ForLoop {{ pat: {pat}, arg: {arg}, body: {body}, .. }}) \
+                = higher::ForLoop::hir({expr})"
             );
             self.pat(pat);
             self.expr(arg);
@@ -369,7 +376,7 @@ impl<'a, 'tcx> PrintVisitor<'a, 'tcx> {
             return;
         }
 
-        let kind = |kind| out!("if let ExprKind::{kind} = {expr}.kind;");
+        let kind = |kind| chain!(self, "let ExprKind::{kind} = {expr}.kind");
         macro_rules! kind {
             ($($t:tt)*) => (kind(format_args!($($t)*)));
         }
@@ -383,7 +390,7 @@ impl<'a, 'tcx> PrintVisitor<'a, 'tcx> {
                 // if it's a path
                 if let Some(TyKind::Path(ref qpath)) = let_expr.value.ty.as_ref().map(|ty| &ty.kind) {
                     bind!(self, qpath);
-                    out!("if let TyKind::Path(ref {qpath}) = {let_expr}.ty.kind;");
+                    chain!(self, "let TyKind::Path(ref {qpath}) = {let_expr}.ty.kind");
                     self.qpath(qpath);
                 }
                 self.expr(field!(let_expr.init));
@@ -419,7 +426,7 @@ impl<'a, 'tcx> PrintVisitor<'a, 'tcx> {
             ExprKind::Binary(op, left, right) => {
                 bind!(self, op, left, right);
                 kind!("Binary({op}, {left}, {right})");
-                out!("if BinOpKind::{:?} == {op}.node;", op.value.node);
+                chain!(self, "BinOpKind::{:?} == {op}.node", op.value.node);
                 self.expr(left);
                 self.expr(right);
             },
@@ -438,7 +445,7 @@ impl<'a, 'tcx> PrintVisitor<'a, 'tcx> {
                 kind!("Cast({expr}, {cast_ty})");
                 if let TyKind::Path(ref qpath) = cast_ty.value.kind {
                     bind!(self, qpath);
-                    out!("if let TyKind::Path(ref {qpath}) = {cast_ty}.kind;");
+                    chain!(self, "let TyKind::Path(ref {qpath}) = {cast_ty}.kind");
                     self.qpath(qpath);
                 }
                 self.expr(expr);
@@ -485,7 +492,7 @@ impl<'a, 'tcx> PrintVisitor<'a, 'tcx> {
 
                 bind!(self, fn_decl, body_id);
                 kind!("Closure(CaptureBy::{capture_clause:?}, {fn_decl}, {body_id}, _, {movability})");
-                out!("if let {ret_ty} = {fn_decl}.output;");
+                chain!(self, "let {ret_ty} = {fn_decl}.output");
                 self.body(body_id);
             },
             ExprKind::Yield(sub, source) => {
@@ -509,7 +516,7 @@ impl<'a, 'tcx> PrintVisitor<'a, 'tcx> {
             ExprKind::AssignOp(op, target, value) => {
                 bind!(self, op, target, value);
                 kind!("AssignOp({op}, {target}, {value})");
-                out!("if BinOpKind::{:?} == {op}.node;", op.value.node);
+                chain!(self, "BinOpKind::{:?} == {op}.node", op.value.node);
                 self.expr(target);
                 self.expr(value);
             },
@@ -573,10 +580,10 @@ impl<'a, 'tcx> PrintVisitor<'a, 'tcx> {
                 kind!("Repeat({value}, {length})");
                 self.expr(value);
                 match length.value {
-                    ArrayLen::Infer(..) => out!("if let ArrayLen::Infer(..) = length;"),
+                    ArrayLen::Infer(..) => chain!(self, "let ArrayLen::Infer(..) = length"),
                     ArrayLen::Body(anon_const) => {
                         bind!(self, anon_const);
-                        out!("if let ArrayLen::Body({anon_const}) = {length};");
+                        chain!(self, "let ArrayLen::Body({anon_const}) = {length}");
                         self.body(field!(anon_const.body));
                     },
                 }
@@ -600,12 +607,12 @@ impl<'a, 'tcx> PrintVisitor<'a, 'tcx> {
     fn body(&self, body_id: &Binding<hir::BodyId>) {
         let expr = self.cx.tcx.hir().body(body_id.value).value;
         bind!(self, expr);
-        out!("let {expr} = &cx.tcx.hir().body({body_id}).value;");
+        chain!(self, "{expr} = &cx.tcx.hir().body({body_id}).value");
         self.expr(expr);
     }
 
     fn pat(&self, pat: &Binding<&hir::Pat<'_>>) {
-        let kind = |kind| out!("if let PatKind::{kind} = {pat}.kind;");
+        let kind = |kind| chain!(self, "let PatKind::{kind} = {pat}.kind");
         macro_rules! kind {
             ($($t:tt)*) => (kind(format_args!($($t)*)));
         }
@@ -688,7 +695,7 @@ impl<'a, 'tcx> PrintVisitor<'a, 'tcx> {
     }
 
     fn stmt(&self, stmt: &Binding<&hir::Stmt<'_>>) {
-        let kind = |kind| out!("if let StmtKind::{kind} = {stmt}.kind;");
+        let kind = |kind| chain!(self, "let StmtKind::{kind} = {stmt}.kind");
         macro_rules! kind {
             ($($t:tt)*) => (kind(format_args!($($t)*)));
         }
diff --git a/src/tools/clippy/clippy_lints/src/utils/internal_lints.rs b/src/tools/clippy/clippy_lints/src/utils/internal_lints.rs
index 85bcbc7ad236..71f6c9909ddd 100644
--- a/src/tools/clippy/clippy_lints/src/utils/internal_lints.rs
+++ b/src/tools/clippy/clippy_lints/src/utils/internal_lints.rs
@@ -1,1566 +1,12 @@
-use crate::utils::internal_lints::metadata_collector::is_deprecated_lint;
-use clippy_utils::consts::{constant_simple, Constant};
-use clippy_utils::diagnostics::{span_lint, span_lint_and_help, span_lint_and_sugg, span_lint_and_then};
-use clippy_utils::macros::root_macro_call_first_node;
-use clippy_utils::source::{snippet, snippet_with_applicability};
-use clippy_utils::ty::match_type;
-use clippy_utils::{
-    def_path_res, higher, is_else_clause, is_expn_of, is_expr_path_def_path, is_lint_allowed, match_any_def_paths,
-    match_def_path, method_calls, paths, peel_blocks_with_stmt, peel_hir_expr_refs, SpanlessEq,
-};
-use if_chain::if_chain;
-use rustc_ast as ast;
-use rustc_ast::ast::{Crate, ItemKind, LitKind, ModKind, NodeId};
-use rustc_ast::visit::FnKind;
-use rustc_data_structures::fx::{FxHashMap, FxHashSet};
-use rustc_errors::Applicability;
-use rustc_hir as hir;
-use rustc_hir::def::{DefKind, Namespace, Res};
-use rustc_hir::def_id::DefId;
-use rustc_hir::hir_id::CRATE_HIR_ID;
-use rustc_hir::intravisit::Visitor;
-use rustc_hir::{
-    BinOpKind, Block, Closure, Expr, ExprKind, HirId, Item, Local, MutTy, Mutability, Node, Path, Stmt, StmtKind,
-    TyKind, UnOp,
-};
-use rustc_hir_analysis::hir_ty_to_ty;
-use rustc_lint::{EarlyContext, EarlyLintPass, LateContext, LateLintPass, LintContext};
-use rustc_middle::hir::nested_filter;
-use rustc_middle::mir::interpret::{Allocation, ConstValue, GlobalAlloc};
-use rustc_middle::ty::{
-    self, fast_reject::SimplifiedTypeGen, subst::GenericArgKind, AssocKind, DefIdTree, FloatTy, Ty,
-};
-use rustc_semver::RustcVersion;
-use rustc_session::{declare_lint_pass, declare_tool_lint, impl_lint_pass};
-use rustc_span::source_map::Spanned;
-use rustc_span::symbol::{Ident, Symbol};
-use rustc_span::{sym, BytePos, Span};
-
-use std::borrow::{Borrow, Cow};
-use std::str;
-
-#[cfg(feature = "internal")]
+pub mod clippy_lints_internal;
+pub mod collapsible_calls;
+pub mod compiler_lint_functions;
+pub mod if_chain_style;
+pub mod interning_defined_symbol;
+pub mod invalid_paths;
+pub mod lint_without_lint_pass;
 pub mod metadata_collector;
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// Checks for various things we like to keep tidy in clippy.
-    ///
-    /// ### Why is this bad?
-    /// We like to pretend we're an example of tidy code.
-    ///
-    /// ### Example
-    /// Wrong ordering of the util::paths constants.
-    pub CLIPPY_LINTS_INTERNAL,
-    internal,
-    "various things that will negatively affect your clippy experience"
-}
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// Ensures every lint is associated to a `LintPass`.
-    ///
-    /// ### Why is this bad?
-    /// The compiler only knows lints via a `LintPass`. Without
-    /// putting a lint to a `LintPass::get_lints()`'s return, the compiler will not
-    /// know the name of the lint.
-    ///
-    /// ### Known problems
-    /// Only checks for lints associated using the
-    /// `declare_lint_pass!`, `impl_lint_pass!`, and `lint_array!` macros.
-    ///
-    /// ### Example
-    /// ```rust,ignore
-    /// declare_lint! { pub LINT_1, ... }
-    /// declare_lint! { pub LINT_2, ... }
-    /// declare_lint! { pub FORGOTTEN_LINT, ... }
-    /// // ...
-    /// declare_lint_pass!(Pass => [LINT_1, LINT_2]);
-    /// // missing FORGOTTEN_LINT
-    /// ```
-    pub LINT_WITHOUT_LINT_PASS,
-    internal,
-    "declaring a lint without associating it in a LintPass"
-}
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// Checks for calls to `cx.span_lint*` and suggests to use the `utils::*`
-    /// variant of the function.
-    ///
-    /// ### Why is this bad?
-    /// The `utils::*` variants also add a link to the Clippy documentation to the
-    /// warning/error messages.
-    ///
-    /// ### Example
-    /// ```rust,ignore
-    /// cx.span_lint(LINT_NAME, "message");
-    /// ```
-    ///
-    /// Use instead:
-    /// ```rust,ignore
-    /// utils::span_lint(cx, LINT_NAME, "message");
-    /// ```
-    pub COMPILER_LINT_FUNCTIONS,
-    internal,
-    "usage of the lint functions of the compiler instead of the utils::* variant"
-}
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// Checks for calls to `cx.outer().expn_data()` and suggests to use
-    /// the `cx.outer_expn_data()`
-    ///
-    /// ### Why is this bad?
-    /// `cx.outer_expn_data()` is faster and more concise.
-    ///
-    /// ### Example
-    /// ```rust,ignore
-    /// expr.span.ctxt().outer().expn_data()
-    /// ```
-    ///
-    /// Use instead:
-    /// ```rust,ignore
-    /// expr.span.ctxt().outer_expn_data()
-    /// ```
-    pub OUTER_EXPN_EXPN_DATA,
-    internal,
-    "using `cx.outer_expn().expn_data()` instead of `cx.outer_expn_data()`"
-}
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// Not an actual lint. This lint is only meant for testing our customized internal compiler
-    /// error message by calling `panic`.
-    ///
-    /// ### Why is this bad?
-    /// ICE in large quantities can damage your teeth
-    ///
-    /// ### Example
-    /// ```rust,ignore
-    /// 🍦🍦🍦🍦🍦
-    /// ```
-    pub PRODUCE_ICE,
-    internal,
-    "this message should not appear anywhere as we ICE before and don't emit the lint"
-}
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// Checks for cases of an auto-generated lint without an updated description,
-    /// i.e. `default lint description`.
-    ///
-    /// ### Why is this bad?
-    /// Indicates that the lint is not finished.
-    ///
-    /// ### Example
-    /// ```rust,ignore
-    /// declare_lint! { pub COOL_LINT, nursery, "default lint description" }
-    /// ```
-    ///
-    /// Use instead:
-    /// ```rust,ignore
-    /// declare_lint! { pub COOL_LINT, nursery, "a great new lint" }
-    /// ```
-    pub DEFAULT_LINT,
-    internal,
-    "found 'default lint description' in a lint declaration"
-}
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// Lints `span_lint_and_then` function calls, where the
-    /// closure argument has only one statement and that statement is a method
-    /// call to `span_suggestion`, `span_help`, `span_note` (using the same
-    /// span), `help` or `note`.
-    ///
-    /// These usages of `span_lint_and_then` should be replaced with one of the
-    /// wrapper functions `span_lint_and_sugg`, span_lint_and_help`, or
-    /// `span_lint_and_note`.
-    ///
-    /// ### Why is this bad?
-    /// Using the wrapper `span_lint_and_*` functions, is more
-    /// convenient, readable and less error prone.
-    ///
-    /// ### Example
-    /// ```rust,ignore
-    /// span_lint_and_then(cx, TEST_LINT, expr.span, lint_msg, |diag| {
-    ///     diag.span_suggestion(
-    ///         expr.span,
-    ///         help_msg,
-    ///         sugg.to_string(),
-    ///         Applicability::MachineApplicable,
-    ///     );
-    /// });
-    /// span_lint_and_then(cx, TEST_LINT, expr.span, lint_msg, |diag| {
-    ///     diag.span_help(expr.span, help_msg);
-    /// });
-    /// span_lint_and_then(cx, TEST_LINT, expr.span, lint_msg, |diag| {
-    ///     diag.help(help_msg);
-    /// });
-    /// span_lint_and_then(cx, TEST_LINT, expr.span, lint_msg, |diag| {
-    ///     diag.span_note(expr.span, note_msg);
-    /// });
-    /// span_lint_and_then(cx, TEST_LINT, expr.span, lint_msg, |diag| {
-    ///     diag.note(note_msg);
-    /// });
-    /// ```
-    ///
-    /// Use instead:
-    /// ```rust,ignore
-    /// span_lint_and_sugg(
-    ///     cx,
-    ///     TEST_LINT,
-    ///     expr.span,
-    ///     lint_msg,
-    ///     help_msg,
-    ///     sugg.to_string(),
-    ///     Applicability::MachineApplicable,
-    /// );
-    /// span_lint_and_help(cx, TEST_LINT, expr.span, lint_msg, Some(expr.span), help_msg);
-    /// span_lint_and_help(cx, TEST_LINT, expr.span, lint_msg, None, help_msg);
-    /// span_lint_and_note(cx, TEST_LINT, expr.span, lint_msg, Some(expr.span), note_msg);
-    /// span_lint_and_note(cx, TEST_LINT, expr.span, lint_msg, None, note_msg);
-    /// ```
-    pub COLLAPSIBLE_SPAN_LINT_CALLS,
-    internal,
-    "found collapsible `span_lint_and_then` calls"
-}
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// Checks for usages of def paths when a diagnostic item or a `LangItem` could be used.
-    ///
-    /// ### Why is this bad?
-    /// The path for an item is subject to change and is less efficient to look up than a
-    /// diagnostic item or a `LangItem`.
-    ///
-    /// ### Example
-    /// ```rust,ignore
-    /// utils::match_type(cx, ty, &paths::VEC)
-    /// ```
-    ///
-    /// Use instead:
-    /// ```rust,ignore
-    /// utils::is_type_diagnostic_item(cx, ty, sym::Vec)
-    /// ```
-    pub UNNECESSARY_DEF_PATH,
-    internal,
-    "using a def path when a diagnostic item or a `LangItem` is available"
-}
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// Checks the paths module for invalid paths.
-    ///
-    /// ### Why is this bad?
-    /// It indicates a bug in the code.
-    ///
-    /// ### Example
-    /// None.
-    pub INVALID_PATHS,
-    internal,
-    "invalid path"
-}
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// Checks for interning symbols that have already been pre-interned and defined as constants.
-    ///
-    /// ### Why is this bad?
-    /// It's faster and easier to use the symbol constant.
-    ///
-    /// ### Example
-    /// ```rust,ignore
-    /// let _ = sym!(f32);
-    /// ```
-    ///
-    /// Use instead:
-    /// ```rust,ignore
-    /// let _ = sym::f32;
-    /// ```
-    pub INTERNING_DEFINED_SYMBOL,
-    internal,
-    "interning a symbol that is pre-interned and defined as a constant"
-}
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// Checks for unnecessary conversion from Symbol to a string.
-    ///
-    /// ### Why is this bad?
-    /// It's faster use symbols directly instead of strings.
-    ///
-    /// ### Example
-    /// ```rust,ignore
-    /// symbol.as_str() == "clippy";
-    /// ```
-    ///
-    /// Use instead:
-    /// ```rust,ignore
-    /// symbol == sym::clippy;
-    /// ```
-    pub UNNECESSARY_SYMBOL_STR,
-    internal,
-    "unnecessary conversion between Symbol and string"
-}
-
-declare_clippy_lint! {
-    /// Finds unidiomatic usage of `if_chain!`
-    pub IF_CHAIN_STYLE,
-    internal,
-    "non-idiomatic `if_chain!` usage"
-}
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// Checks for invalid `clippy::version` attributes.
-    ///
-    /// Valid values are:
-    /// * "pre 1.29.0"
-    /// * any valid semantic version
-    pub INVALID_CLIPPY_VERSION_ATTRIBUTE,
-    internal,
-    "found an invalid `clippy::version` attribute"
-}
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// Checks for declared clippy lints without the `clippy::version` attribute.
-    ///
-    pub MISSING_CLIPPY_VERSION_ATTRIBUTE,
-    internal,
-    "found clippy lint without `clippy::version` attribute"
-}
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// Check that the `extract_msrv_attr!` macro is used, when a lint has a MSRV.
-    ///
-    pub MISSING_MSRV_ATTR_IMPL,
-    internal,
-    "checking if all necessary steps were taken when adding a MSRV to a lint"
-}
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// Checks for cases of an auto-generated deprecated lint without an updated reason,
-    /// i.e. `"default deprecation note"`.
-    ///
-    /// ### Why is this bad?
-    /// Indicates that the documentation is incomplete.
-    ///
-    /// ### Example
-    /// ```rust,ignore
-    /// declare_deprecated_lint! {
-    ///     /// ### What it does
-    ///     /// Nothing. This lint has been deprecated.
-    ///     ///
-    ///     /// ### Deprecation reason
-    ///     /// TODO
-    ///     #[clippy::version = "1.63.0"]
-    ///     pub COOL_LINT,
-    ///     "default deprecation note"
-    /// }
-    /// ```
-    ///
-    /// Use instead:
-    /// ```rust,ignore
-    /// declare_deprecated_lint! {
-    ///     /// ### What it does
-    ///     /// Nothing. This lint has been deprecated.
-    ///     ///
-    ///     /// ### Deprecation reason
-    ///     /// This lint has been replaced by `cooler_lint`
-    ///     #[clippy::version = "1.63.0"]
-    ///     pub COOL_LINT,
-    ///     "this lint has been replaced by `cooler_lint`"
-    /// }
-    /// ```
-    pub DEFAULT_DEPRECATION_REASON,
-    internal,
-    "found 'default deprecation note' in a deprecated lint declaration"
-}
-
-declare_lint_pass!(ClippyLintsInternal => [CLIPPY_LINTS_INTERNAL]);
-
-impl EarlyLintPass for ClippyLintsInternal {
-    fn check_crate(&mut self, cx: &EarlyContext<'_>, krate: &Crate) {
-        if let Some(utils) = krate.items.iter().find(|item| item.ident.name.as_str() == "utils") {
-            if let ItemKind::Mod(_, ModKind::Loaded(ref items, ..)) = utils.kind {
-                if let Some(paths) = items.iter().find(|item| item.ident.name.as_str() == "paths") {
-                    if let ItemKind::Mod(_, ModKind::Loaded(ref items, ..)) = paths.kind {
-                        let mut last_name: Option<&str> = None;
-                        for item in items {
-                            let name = item.ident.as_str();
-                            if let Some(last_name) = last_name {
-                                if *last_name > *name {
-                                    span_lint(
-                                        cx,
-                                        CLIPPY_LINTS_INTERNAL,
-                                        item.span,
-                                        "this constant should be before the previous constant due to lexical \
-                                         ordering",
-                                    );
-                                }
-                            }
-                            last_name = Some(name);
-                        }
-                    }
-                }
-            }
-        }
-    }
-}
-
-#[derive(Clone, Debug, Default)]
-pub struct LintWithoutLintPass {
-    declared_lints: FxHashMap<Symbol, Span>,
-    registered_lints: FxHashSet<Symbol>,
-}
-
-impl_lint_pass!(LintWithoutLintPass => [DEFAULT_LINT, LINT_WITHOUT_LINT_PASS, INVALID_CLIPPY_VERSION_ATTRIBUTE, MISSING_CLIPPY_VERSION_ATTRIBUTE, DEFAULT_DEPRECATION_REASON]);
-
-impl<'tcx> LateLintPass<'tcx> for LintWithoutLintPass {
-    fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'_>) {
-        if is_lint_allowed(cx, DEFAULT_LINT, item.hir_id())
-            || is_lint_allowed(cx, DEFAULT_DEPRECATION_REASON, item.hir_id())
-        {
-            return;
-        }
-
-        if let hir::ItemKind::Static(ty, Mutability::Not, body_id) = item.kind {
-            let is_lint_ref_ty = is_lint_ref_type(cx, ty);
-            if is_deprecated_lint(cx, ty) || is_lint_ref_ty {
-                check_invalid_clippy_version_attribute(cx, item);
-
-                let expr = &cx.tcx.hir().body(body_id).value;
-                let fields;
-                if is_lint_ref_ty {
-                    if let ExprKind::AddrOf(_, _, inner_exp) = expr.kind
-                        && let ExprKind::Struct(_, struct_fields, _) = inner_exp.kind {
-                            fields = struct_fields;
-                    } else {
-                        return;
-                    }
-                } else if let ExprKind::Struct(_, struct_fields, _) = expr.kind {
-                    fields = struct_fields;
-                } else {
-                    return;
-                }
-
-                let field = fields
-                    .iter()
-                    .find(|f| f.ident.as_str() == "desc")
-                    .expect("lints must have a description field");
-
-                if let ExprKind::Lit(Spanned {
-                    node: LitKind::Str(ref sym, _),
-                    ..
-                }) = field.expr.kind
-                {
-                    let sym_str = sym.as_str();
-                    if is_lint_ref_ty {
-                        if sym_str == "default lint description" {
-                            span_lint(
-                                cx,
-                                DEFAULT_LINT,
-                                item.span,
-                                &format!("the lint `{}` has the default lint description", item.ident.name),
-                            );
-                        }
-
-                        self.declared_lints.insert(item.ident.name, item.span);
-                    } else if sym_str == "default deprecation note" {
-                        span_lint(
-                            cx,
-                            DEFAULT_DEPRECATION_REASON,
-                            item.span,
-                            &format!("the lint `{}` has the default deprecation reason", item.ident.name),
-                        );
-                    }
-                }
-            }
-        } else if let Some(macro_call) = root_macro_call_first_node(cx, item) {
-            if !matches!(
-                cx.tcx.item_name(macro_call.def_id).as_str(),
-                "impl_lint_pass" | "declare_lint_pass"
-            ) {
-                return;
-            }
-            if let hir::ItemKind::Impl(hir::Impl {
-                of_trait: None,
-                items: impl_item_refs,
-                ..
-            }) = item.kind
-            {
-                let mut collector = LintCollector {
-                    output: &mut self.registered_lints,
-                    cx,
-                };
-                let body_id = cx.tcx.hir().body_owned_by(
-                    cx.tcx.hir().local_def_id(
-                        impl_item_refs
-                            .iter()
-                            .find(|iiref| iiref.ident.as_str() == "get_lints")
-                            .expect("LintPass needs to implement get_lints")
-                            .id
-                            .hir_id(),
-                    ),
-                );
-                collector.visit_expr(cx.tcx.hir().body(body_id).value);
-            }
-        }
-    }
-
-    fn check_crate_post(&mut self, cx: &LateContext<'tcx>) {
-        if is_lint_allowed(cx, LINT_WITHOUT_LINT_PASS, CRATE_HIR_ID) {
-            return;
-        }
-
-        for (lint_name, &lint_span) in &self.declared_lints {
-            // When using the `declare_tool_lint!` macro, the original `lint_span`'s
-            // file points to "<rustc macros>".
-            // `compiletest-rs` thinks that's an error in a different file and
-            // just ignores it. This causes the test in compile-fail/lint_pass
-            // not able to capture the error.
-            // Therefore, we need to climb the macro expansion tree and find the
-            // actual span that invoked `declare_tool_lint!`:
-            let lint_span = lint_span.ctxt().outer_expn_data().call_site;
-
-            if !self.registered_lints.contains(lint_name) {
-                span_lint(
-                    cx,
-                    LINT_WITHOUT_LINT_PASS,
-                    lint_span,
-                    &format!("the lint `{lint_name}` is not added to any `LintPass`"),
-                );
-            }
-        }
-    }
-}
-
-fn is_lint_ref_type<'tcx>(cx: &LateContext<'tcx>, ty: &hir::Ty<'_>) -> bool {
-    if let TyKind::Rptr(
-        _,
-        MutTy {
-            ty: inner,
-            mutbl: Mutability::Not,
-        },
-    ) = ty.kind
-    {
-        if let TyKind::Path(ref path) = inner.kind {
-            if let Res::Def(DefKind::Struct, def_id) = cx.qpath_res(path, inner.hir_id) {
-                return match_def_path(cx, def_id, &paths::LINT);
-            }
-        }
-    }
-
-    false
-}
-
-fn check_invalid_clippy_version_attribute(cx: &LateContext<'_>, item: &'_ Item<'_>) {
-    if let Some(value) = extract_clippy_version_value(cx, item) {
-        // The `sym!` macro doesn't work as it only expects a single token.
-        // It's better to keep it this way and have a direct `Symbol::intern` call here.
-        if value == Symbol::intern("pre 1.29.0") {
-            return;
-        }
-
-        if RustcVersion::parse(value.as_str()).is_err() {
-            span_lint_and_help(
-                cx,
-                INVALID_CLIPPY_VERSION_ATTRIBUTE,
-                item.span,
-                "this item has an invalid `clippy::version` attribute",
-                None,
-                "please use a valid semantic version, see `doc/adding_lints.md`",
-            );
-        }
-    } else {
-        span_lint_and_help(
-            cx,
-            MISSING_CLIPPY_VERSION_ATTRIBUTE,
-            item.span,
-            "this lint is missing the `clippy::version` attribute or version value",
-            None,
-            "please use a `clippy::version` attribute, see `doc/adding_lints.md`",
-        );
-    }
-}
-
-/// This function extracts the version value of a `clippy::version` attribute if the given value has
-/// one
-fn extract_clippy_version_value(cx: &LateContext<'_>, item: &'_ Item<'_>) -> Option<Symbol> {
-    let attrs = cx.tcx.hir().attrs(item.hir_id());
-    attrs.iter().find_map(|attr| {
-        if_chain! {
-            // Identify attribute
-            if let ast::AttrKind::Normal(ref attr_kind) = &attr.kind;
-            if let [tool_name, attr_name] = &attr_kind.item.path.segments[..];
-            if tool_name.ident.name == sym::clippy;
-            if attr_name.ident.name == sym::version;
-            if let Some(version) = attr.value_str();
-            then {
-                Some(version)
-            } else {
-                None
-            }
-        }
-    })
-}
-
-struct LintCollector<'a, 'tcx> {
-    output: &'a mut FxHashSet<Symbol>,
-    cx: &'a LateContext<'tcx>,
-}
-
-impl<'a, 'tcx> Visitor<'tcx> for LintCollector<'a, 'tcx> {
-    type NestedFilter = nested_filter::All;
-
-    fn visit_path(&mut self, path: &'tcx Path<'_>, _: HirId) {
-        if path.segments.len() == 1 {
-            self.output.insert(path.segments[0].ident.name);
-        }
-    }
-
-    fn nested_visit_map(&mut self) -> Self::Map {
-        self.cx.tcx.hir()
-    }
-}
-
-#[derive(Clone, Default)]
-pub struct CompilerLintFunctions {
-    map: FxHashMap<&'static str, &'static str>,
-}
-
-impl CompilerLintFunctions {
-    #[must_use]
-    pub fn new() -> Self {
-        let mut map = FxHashMap::default();
-        map.insert("span_lint", "utils::span_lint");
-        map.insert("struct_span_lint", "utils::span_lint");
-        map.insert("lint", "utils::span_lint");
-        map.insert("span_lint_note", "utils::span_lint_and_note");
-        map.insert("span_lint_help", "utils::span_lint_and_help");
-        Self { map }
-    }
-}
-
-impl_lint_pass!(CompilerLintFunctions => [COMPILER_LINT_FUNCTIONS]);
-
-impl<'tcx> LateLintPass<'tcx> for CompilerLintFunctions {
-    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
-        if is_lint_allowed(cx, COMPILER_LINT_FUNCTIONS, expr.hir_id) {
-            return;
-        }
-
-        if_chain! {
-            if let ExprKind::MethodCall(path, self_arg, _, _) = &expr.kind;
-            let fn_name = path.ident;
-            if let Some(sugg) = self.map.get(fn_name.as_str());
-            let ty = cx.typeck_results().expr_ty(self_arg).peel_refs();
-            if match_type(cx, ty, &paths::EARLY_CONTEXT)
-                || match_type(cx, ty, &paths::LATE_CONTEXT);
-            then {
-                span_lint_and_help(
-                    cx,
-                    COMPILER_LINT_FUNCTIONS,
-                    path.ident.span,
-                    "usage of a compiler lint function",
-                    None,
-                    &format!("please use the Clippy variant of this function: `{sugg}`"),
-                );
-            }
-        }
-    }
-}
-
-declare_lint_pass!(OuterExpnDataPass => [OUTER_EXPN_EXPN_DATA]);
-
-impl<'tcx> LateLintPass<'tcx> for OuterExpnDataPass {
-    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>) {
-        if is_lint_allowed(cx, OUTER_EXPN_EXPN_DATA, expr.hir_id) {
-            return;
-        }
-
-        let (method_names, arg_lists, spans) = method_calls(expr, 2);
-        let method_names: Vec<&str> = method_names.iter().map(Symbol::as_str).collect();
-        if_chain! {
-            if let ["expn_data", "outer_expn"] = method_names.as_slice();
-            let (self_arg, args)= arg_lists[1];
-            if args.is_empty();
-            let self_ty = cx.typeck_results().expr_ty(self_arg).peel_refs();
-            if match_type(cx, self_ty, &paths::SYNTAX_CONTEXT);
-            then {
-                span_lint_and_sugg(
-                    cx,
-                    OUTER_EXPN_EXPN_DATA,
-                    spans[1].with_hi(expr.span.hi()),
-                    "usage of `outer_expn().expn_data()`",
-                    "try",
-                    "outer_expn_data()".to_string(),
-                    Applicability::MachineApplicable,
-                );
-            }
-        }
-    }
-}
-
-declare_lint_pass!(ProduceIce => [PRODUCE_ICE]);
-
-impl EarlyLintPass for ProduceIce {
-    fn check_fn(&mut self, _: &EarlyContext<'_>, fn_kind: FnKind<'_>, _: Span, _: NodeId) {
-        assert!(!is_trigger_fn(fn_kind), "Would you like some help with that?");
-    }
-}
-
-fn is_trigger_fn(fn_kind: FnKind<'_>) -> bool {
-    match fn_kind {
-        FnKind::Fn(_, ident, ..) => ident.name.as_str() == "it_looks_like_you_are_trying_to_kill_clippy",
-        FnKind::Closure(..) => false,
-    }
-}
-
-declare_lint_pass!(CollapsibleCalls => [COLLAPSIBLE_SPAN_LINT_CALLS]);
-
-impl<'tcx> LateLintPass<'tcx> for CollapsibleCalls {
-    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>) {
-        if is_lint_allowed(cx, COLLAPSIBLE_SPAN_LINT_CALLS, expr.hir_id) {
-            return;
-        }
-
-        if_chain! {
-            if let ExprKind::Call(func, and_then_args) = expr.kind;
-            if is_expr_path_def_path(cx, func, &["clippy_utils", "diagnostics", "span_lint_and_then"]);
-            if and_then_args.len() == 5;
-            if let ExprKind::Closure(&Closure { body, .. }) = &and_then_args[4].kind;
-            let body = cx.tcx.hir().body(body);
-            let only_expr = peel_blocks_with_stmt(body.value);
-            if let ExprKind::MethodCall(ps, recv, span_call_args, _) = &only_expr.kind;
-            if let ExprKind::Path(..) = recv.kind;
-            then {
-                let and_then_snippets = get_and_then_snippets(cx, and_then_args);
-                let mut sle = SpanlessEq::new(cx).deny_side_effects();
-                match ps.ident.as_str() {
-                    "span_suggestion" if sle.eq_expr(&and_then_args[2], &span_call_args[0]) => {
-                        suggest_suggestion(cx, expr, &and_then_snippets, &span_suggestion_snippets(cx, span_call_args));
-                    },
-                    "span_help" if sle.eq_expr(&and_then_args[2], &span_call_args[0]) => {
-                        let help_snippet = snippet(cx, span_call_args[1].span, r#""...""#);
-                        suggest_help(cx, expr, &and_then_snippets, help_snippet.borrow(), true);
-                    },
-                    "span_note" if sle.eq_expr(&and_then_args[2], &span_call_args[0]) => {
-                        let note_snippet = snippet(cx, span_call_args[1].span, r#""...""#);
-                        suggest_note(cx, expr, &and_then_snippets, note_snippet.borrow(), true);
-                    },
-                    "help" => {
-                        let help_snippet = snippet(cx, span_call_args[0].span, r#""...""#);
-                        suggest_help(cx, expr, &and_then_snippets, help_snippet.borrow(), false);
-                    }
-                    "note" => {
-                        let note_snippet = snippet(cx, span_call_args[0].span, r#""...""#);
-                        suggest_note(cx, expr, &and_then_snippets, note_snippet.borrow(), false);
-                    }
-                    _  => (),
-                }
-            }
-        }
-    }
-}
-
-struct AndThenSnippets<'a> {
-    cx: Cow<'a, str>,
-    lint: Cow<'a, str>,
-    span: Cow<'a, str>,
-    msg: Cow<'a, str>,
-}
-
-fn get_and_then_snippets<'a, 'hir>(cx: &LateContext<'_>, and_then_snippets: &'hir [Expr<'hir>]) -> AndThenSnippets<'a> {
-    let cx_snippet = snippet(cx, and_then_snippets[0].span, "cx");
-    let lint_snippet = snippet(cx, and_then_snippets[1].span, "..");
-    let span_snippet = snippet(cx, and_then_snippets[2].span, "span");
-    let msg_snippet = snippet(cx, and_then_snippets[3].span, r#""...""#);
-
-    AndThenSnippets {
-        cx: cx_snippet,
-        lint: lint_snippet,
-        span: span_snippet,
-        msg: msg_snippet,
-    }
-}
-
-struct SpanSuggestionSnippets<'a> {
-    help: Cow<'a, str>,
-    sugg: Cow<'a, str>,
-    applicability: Cow<'a, str>,
-}
-
-fn span_suggestion_snippets<'a, 'hir>(
-    cx: &LateContext<'_>,
-    span_call_args: &'hir [Expr<'hir>],
-) -> SpanSuggestionSnippets<'a> {
-    let help_snippet = snippet(cx, span_call_args[1].span, r#""...""#);
-    let sugg_snippet = snippet(cx, span_call_args[2].span, "..");
-    let applicability_snippet = snippet(cx, span_call_args[3].span, "Applicability::MachineApplicable");
-
-    SpanSuggestionSnippets {
-        help: help_snippet,
-        sugg: sugg_snippet,
-        applicability: applicability_snippet,
-    }
-}
-
-fn suggest_suggestion(
-    cx: &LateContext<'_>,
-    expr: &Expr<'_>,
-    and_then_snippets: &AndThenSnippets<'_>,
-    span_suggestion_snippets: &SpanSuggestionSnippets<'_>,
-) {
-    span_lint_and_sugg(
-        cx,
-        COLLAPSIBLE_SPAN_LINT_CALLS,
-        expr.span,
-        "this call is collapsible",
-        "collapse into",
-        format!(
-            "span_lint_and_sugg({}, {}, {}, {}, {}, {}, {})",
-            and_then_snippets.cx,
-            and_then_snippets.lint,
-            and_then_snippets.span,
-            and_then_snippets.msg,
-            span_suggestion_snippets.help,
-            span_suggestion_snippets.sugg,
-            span_suggestion_snippets.applicability
-        ),
-        Applicability::MachineApplicable,
-    );
-}
-
-fn suggest_help(
-    cx: &LateContext<'_>,
-    expr: &Expr<'_>,
-    and_then_snippets: &AndThenSnippets<'_>,
-    help: &str,
-    with_span: bool,
-) {
-    let option_span = if with_span {
-        format!("Some({})", and_then_snippets.span)
-    } else {
-        "None".to_string()
-    };
-
-    span_lint_and_sugg(
-        cx,
-        COLLAPSIBLE_SPAN_LINT_CALLS,
-        expr.span,
-        "this call is collapsible",
-        "collapse into",
-        format!(
-            "span_lint_and_help({}, {}, {}, {}, {}, {help})",
-            and_then_snippets.cx, and_then_snippets.lint, and_then_snippets.span, and_then_snippets.msg, &option_span,
-        ),
-        Applicability::MachineApplicable,
-    );
-}
-
-fn suggest_note(
-    cx: &LateContext<'_>,
-    expr: &Expr<'_>,
-    and_then_snippets: &AndThenSnippets<'_>,
-    note: &str,
-    with_span: bool,
-) {
-    let note_span = if with_span {
-        format!("Some({})", and_then_snippets.span)
-    } else {
-        "None".to_string()
-    };
-
-    span_lint_and_sugg(
-        cx,
-        COLLAPSIBLE_SPAN_LINT_CALLS,
-        expr.span,
-        "this call is collapsible",
-        "collapse into",
-        format!(
-            "span_lint_and_note({}, {}, {}, {}, {note_span}, {note})",
-            and_then_snippets.cx, and_then_snippets.lint, and_then_snippets.span, and_then_snippets.msg,
-        ),
-        Applicability::MachineApplicable,
-    );
-}
-
-declare_lint_pass!(UnnecessaryDefPath => [UNNECESSARY_DEF_PATH]);
-
-#[allow(clippy::too_many_lines)]
-impl<'tcx> LateLintPass<'tcx> for UnnecessaryDefPath {
-    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>) {
-        enum Item {
-            LangItem(Symbol),
-            DiagnosticItem(Symbol),
-        }
-        static PATHS: &[&[&str]] = &[
-            &["clippy_utils", "match_def_path"],
-            &["clippy_utils", "match_trait_method"],
-            &["clippy_utils", "ty", "match_type"],
-            &["clippy_utils", "is_expr_path_def_path"],
-        ];
-
-        if is_lint_allowed(cx, UNNECESSARY_DEF_PATH, expr.hir_id) {
-            return;
-        }
-
-        if_chain! {
-            if let ExprKind::Call(func, [cx_arg, def_arg, args@..]) = expr.kind;
-            if let ExprKind::Path(path) = &func.kind;
-            if let Some(id) = cx.qpath_res(path, func.hir_id).opt_def_id();
-            if let Some(which_path) = match_any_def_paths(cx, id, PATHS);
-            let item_arg = if which_path == 4 { &args[1] } else { &args[0] };
-            // Extract the path to the matched type
-            if let Some(segments) = path_to_matched_type(cx, item_arg);
-            let segments: Vec<&str> = segments.iter().map(|sym| &**sym).collect();
-            if let Some(def_id) = def_path_res(cx, &segments[..], None).opt_def_id();
-            then {
-                // def_path_res will match field names before anything else, but for this we want to match
-                // inherent functions first.
-                let def_id = if cx.tcx.def_kind(def_id) == DefKind::Field {
-                    let method_name = *segments.last().unwrap();
-                    cx.tcx.def_key(def_id).parent
-                        .and_then(|parent_idx|
-                            cx.tcx.inherent_impls(DefId { index: parent_idx, krate: def_id.krate }).iter()
-                                .find_map(|impl_id| cx.tcx.associated_items(*impl_id)
-                                    .find_by_name_and_kind(
-                                        cx.tcx,
-                                        Ident::from_str(method_name),
-                                        AssocKind::Fn,
-                                        *impl_id,
-                                    )
-                                )
-                        )
-                        .map_or(def_id, |item| item.def_id)
-                } else {
-                    def_id
-                };
-
-                // Check if the target item is a diagnostic item or LangItem.
-                let (msg, item) = if let Some(item_name)
-                    = cx.tcx.diagnostic_items(def_id.krate).id_to_name.get(&def_id)
-                {
-                    (
-                        "use of a def path to a diagnostic item",
-                        Item::DiagnosticItem(*item_name),
-                    )
-                } else if let Some(lang_item) = cx.tcx.lang_items().items().iter().position(|id| *id == Some(def_id)) {
-                    let lang_items = def_path_res(cx, &["rustc_hir", "lang_items", "LangItem"], Some(Namespace::TypeNS)).def_id();
-                    let item_name = cx.tcx.adt_def(lang_items).variants().iter().nth(lang_item).unwrap().name;
-                    (
-                        "use of a def path to a `LangItem`",
-                        Item::LangItem(item_name),
-                    )
-                } else {
-                    return;
-                };
-
-                let has_ctor = match cx.tcx.def_kind(def_id) {
-                    DefKind::Struct => {
-                        let variant = cx.tcx.adt_def(def_id).non_enum_variant();
-                        variant.ctor_def_id.is_some() && variant.fields.iter().all(|f| f.vis.is_public())
-                    }
-                    DefKind::Variant => {
-                        let variant = cx.tcx.adt_def(cx.tcx.parent(def_id)).variant_with_id(def_id);
-                        variant.ctor_def_id.is_some() && variant.fields.iter().all(|f| f.vis.is_public())
-                    }
-                    _ => false,
-                };
-
-                let mut app = Applicability::MachineApplicable;
-                let cx_snip = snippet_with_applicability(cx, cx_arg.span, "..", &mut app);
-                let def_snip = snippet_with_applicability(cx, def_arg.span, "..", &mut app);
-                let (sugg, with_note) = match (which_path, item) {
-                    // match_def_path
-                    (0, Item::DiagnosticItem(item)) =>
-                        (format!("{cx_snip}.tcx.is_diagnostic_item(sym::{item}, {def_snip})"), has_ctor),
-                    (0, Item::LangItem(item)) => (
-                        format!("{cx_snip}.tcx.lang_items().require(LangItem::{item}).ok() == Some({def_snip})"),
-                        has_ctor
-                    ),
-                    // match_trait_method
-                    (1, Item::DiagnosticItem(item)) =>
-                        (format!("is_trait_method({cx_snip}, {def_snip}, sym::{item})"), false),
-                    // match_type
-                    (2, Item::DiagnosticItem(item)) =>
-                        (format!("is_type_diagnostic_item({cx_snip}, {def_snip}, sym::{item})"), false),
-                    (2, Item::LangItem(item)) =>
-                        (format!("is_type_lang_item({cx_snip}, {def_snip}, LangItem::{item})"), false),
-                    // is_expr_path_def_path
-                    (3, Item::DiagnosticItem(item)) if has_ctor => (
-                        format!(
-                            "is_res_diag_ctor({cx_snip}, path_res({cx_snip}, {def_snip}), sym::{item})",
-                        ),
-                        false,
-                    ),
-                    (3, Item::LangItem(item)) if has_ctor => (
-                        format!(
-                            "is_res_lang_ctor({cx_snip}, path_res({cx_snip}, {def_snip}), LangItem::{item})",
-                        ),
-                        false,
-                    ),
-                    (3, Item::DiagnosticItem(item)) =>
-                        (format!("is_path_diagnostic_item({cx_snip}, {def_snip}, sym::{item})"), false),
-                    (3, Item::LangItem(item)) => (
-                        format!(
-                            "path_res({cx_snip}, {def_snip}).opt_def_id()\
-                                .map_or(false, |id| {cx_snip}.tcx.lang_items().require(LangItem::{item}).ok() == Some(id))",
-                        ),
-                        false,
-                    ),
-                    _ => return,
-                };
-
-                span_lint_and_then(
-                    cx,
-                    UNNECESSARY_DEF_PATH,
-                    expr.span,
-                    msg,
-                    |diag| {
-                        diag.span_suggestion(expr.span, "try", sugg, app);
-                        if with_note {
-                            diag.help(
-                                "if this `DefId` came from a constructor expression or pattern then the \
-                                    parent `DefId` should be used instead"
-                            );
-                        }
-                    },
-                );
-            }
-        }
-    }
-}
-
-fn path_to_matched_type(cx: &LateContext<'_>, expr: &hir::Expr<'_>) -> Option<Vec<String>> {
-    match peel_hir_expr_refs(expr).0.kind {
-        ExprKind::Path(ref qpath) => match cx.qpath_res(qpath, expr.hir_id) {
-            Res::Local(hir_id) => {
-                let parent_id = cx.tcx.hir().get_parent_node(hir_id);
-                if let Some(Node::Local(Local { init: Some(init), .. })) = cx.tcx.hir().find(parent_id) {
-                    path_to_matched_type(cx, init)
-                } else {
-                    None
-                }
-            },
-            Res::Def(DefKind::Static(_), def_id) => read_mir_alloc_def_path(
-                cx,
-                cx.tcx.eval_static_initializer(def_id).ok()?.inner(),
-                cx.tcx.type_of(def_id),
-            ),
-            Res::Def(DefKind::Const, def_id) => match cx.tcx.const_eval_poly(def_id).ok()? {
-                ConstValue::ByRef { alloc, offset } if offset.bytes() == 0 => {
-                    read_mir_alloc_def_path(cx, alloc.inner(), cx.tcx.type_of(def_id))
-                },
-                _ => None,
-            },
-            _ => None,
-        },
-        ExprKind::Array(exprs) => exprs
-            .iter()
-            .map(|expr| {
-                if let ExprKind::Lit(lit) = &expr.kind {
-                    if let LitKind::Str(sym, _) = lit.node {
-                        return Some((*sym.as_str()).to_owned());
-                    }
-                }
-
-                None
-            })
-            .collect(),
-        _ => None,
-    }
-}
-
-fn read_mir_alloc_def_path<'tcx>(cx: &LateContext<'tcx>, alloc: &'tcx Allocation, ty: Ty<'_>) -> Option<Vec<String>> {
-    let (alloc, ty) = if let ty::Ref(_, ty, Mutability::Not) = *ty.kind() {
-        let &alloc = alloc.provenance().values().next()?;
-        if let GlobalAlloc::Memory(alloc) = cx.tcx.global_alloc(alloc) {
-            (alloc.inner(), ty)
-        } else {
-            return None;
-        }
-    } else {
-        (alloc, ty)
-    };
-
-    if let ty::Array(ty, _) | ty::Slice(ty) = *ty.kind()
-        && let ty::Ref(_, ty, Mutability::Not) = *ty.kind()
-        && ty.is_str()
-    {
-        alloc
-            .provenance()
-            .values()
-            .map(|&alloc| {
-                if let GlobalAlloc::Memory(alloc) = cx.tcx.global_alloc(alloc) {
-                    let alloc = alloc.inner();
-                    str::from_utf8(alloc.inspect_with_uninit_and_ptr_outside_interpreter(0..alloc.len()))
-                        .ok().map(ToOwned::to_owned)
-                } else {
-                    None
-                }
-            })
-            .collect()
-    } else {
-        None
-    }
-}
-
-// This is not a complete resolver for paths. It works on all the paths currently used in the paths
-// module.  That's all it does and all it needs to do.
-pub fn check_path(cx: &LateContext<'_>, path: &[&str]) -> bool {
-    if def_path_res(cx, path, None) != Res::Err {
-        return true;
-    }
-
-    // Some implementations can't be found by `path_to_res`, particularly inherent
-    // implementations of native types. Check lang items.
-    let path_syms: Vec<_> = path.iter().map(|p| Symbol::intern(p)).collect();
-    let lang_items = cx.tcx.lang_items();
-    // This list isn't complete, but good enough for our current list of paths.
-    let incoherent_impls = [
-        SimplifiedTypeGen::FloatSimplifiedType(FloatTy::F32),
-        SimplifiedTypeGen::FloatSimplifiedType(FloatTy::F64),
-        SimplifiedTypeGen::SliceSimplifiedType,
-        SimplifiedTypeGen::StrSimplifiedType,
-    ]
-    .iter()
-    .flat_map(|&ty| cx.tcx.incoherent_impls(ty));
-    for item_def_id in lang_items.items().iter().flatten().chain(incoherent_impls) {
-        let lang_item_path = cx.get_def_path(*item_def_id);
-        if path_syms.starts_with(&lang_item_path) {
-            if let [item] = &path_syms[lang_item_path.len()..] {
-                if matches!(
-                    cx.tcx.def_kind(*item_def_id),
-                    DefKind::Mod | DefKind::Enum | DefKind::Trait
-                ) {
-                    for child in cx.tcx.module_children(*item_def_id) {
-                        if child.ident.name == *item {
-                            return true;
-                        }
-                    }
-                } else {
-                    for child in cx.tcx.associated_item_def_ids(*item_def_id) {
-                        if cx.tcx.item_name(*child) == *item {
-                            return true;
-                        }
-                    }
-                }
-            }
-        }
-    }
-
-    false
-}
-
-declare_lint_pass!(InvalidPaths => [INVALID_PATHS]);
-
-impl<'tcx> LateLintPass<'tcx> for InvalidPaths {
-    fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'_>) {
-        let local_def_id = &cx.tcx.parent_module(item.hir_id());
-        let mod_name = &cx.tcx.item_name(local_def_id.to_def_id());
-        if_chain! {
-            if mod_name.as_str() == "paths";
-            if let hir::ItemKind::Const(ty, body_id) = item.kind;
-            let ty = hir_ty_to_ty(cx.tcx, ty);
-            if let ty::Array(el_ty, _) = &ty.kind();
-            if let ty::Ref(_, el_ty, _) = &el_ty.kind();
-            if el_ty.is_str();
-            let body = cx.tcx.hir().body(body_id);
-            let typeck_results = cx.tcx.typeck_body(body_id);
-            if let Some(Constant::Vec(path)) = constant_simple(cx, typeck_results, body.value);
-            let path: Vec<&str> = path.iter().map(|x| {
-                    if let Constant::Str(s) = x {
-                        s.as_str()
-                    } else {
-                        // We checked the type of the constant above
-                        unreachable!()
-                    }
-                }).collect();
-            if !check_path(cx, &path[..]);
-            then {
-                span_lint(cx, INVALID_PATHS, item.span, "invalid path");
-            }
-        }
-    }
-}
-
-#[derive(Default)]
-pub struct InterningDefinedSymbol {
-    // Maps the symbol value to the constant DefId.
-    symbol_map: FxHashMap<u32, DefId>,
-}
-
-impl_lint_pass!(InterningDefinedSymbol => [INTERNING_DEFINED_SYMBOL, UNNECESSARY_SYMBOL_STR]);
-
-impl<'tcx> LateLintPass<'tcx> for InterningDefinedSymbol {
-    fn check_crate(&mut self, cx: &LateContext<'_>) {
-        if !self.symbol_map.is_empty() {
-            return;
-        }
-
-        for &module in &[&paths::KW_MODULE, &paths::SYM_MODULE] {
-            if let Some(def_id) = def_path_res(cx, module, None).opt_def_id() {
-                for item in cx.tcx.module_children(def_id).iter() {
-                    if_chain! {
-                        if let Res::Def(DefKind::Const, item_def_id) = item.res;
-                        let ty = cx.tcx.type_of(item_def_id);
-                        if match_type(cx, ty, &paths::SYMBOL);
-                        if let Ok(ConstValue::Scalar(value)) = cx.tcx.const_eval_poly(item_def_id);
-                        if let Ok(value) = value.to_u32();
-                        then {
-                            self.symbol_map.insert(value, item_def_id);
-                        }
-                    }
-                }
-            }
-        }
-    }
-
-    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
-        if_chain! {
-            if let ExprKind::Call(func, [arg]) = &expr.kind;
-            if let ty::FnDef(def_id, _) = cx.typeck_results().expr_ty(func).kind();
-            if match_def_path(cx, *def_id, &paths::SYMBOL_INTERN);
-            if let Some(Constant::Str(arg)) = constant_simple(cx, cx.typeck_results(), arg);
-            let value = Symbol::intern(&arg).as_u32();
-            if let Some(&def_id) = self.symbol_map.get(&value);
-            then {
-                span_lint_and_sugg(
-                    cx,
-                    INTERNING_DEFINED_SYMBOL,
-                    is_expn_of(expr.span, "sym").unwrap_or(expr.span),
-                    "interning a defined symbol",
-                    "try",
-                    cx.tcx.def_path_str(def_id),
-                    Applicability::MachineApplicable,
-                );
-            }
-        }
-        if let ExprKind::Binary(op, left, right) = expr.kind {
-            if matches!(op.node, BinOpKind::Eq | BinOpKind::Ne) {
-                let data = [
-                    (left, self.symbol_str_expr(left, cx)),
-                    (right, self.symbol_str_expr(right, cx)),
-                ];
-                match data {
-                    // both operands are a symbol string
-                    [(_, Some(left)), (_, Some(right))] => {
-                        span_lint_and_sugg(
-                            cx,
-                            UNNECESSARY_SYMBOL_STR,
-                            expr.span,
-                            "unnecessary `Symbol` to string conversion",
-                            "try",
-                            format!(
-                                "{} {} {}",
-                                left.as_symbol_snippet(cx),
-                                op.node.as_str(),
-                                right.as_symbol_snippet(cx),
-                            ),
-                            Applicability::MachineApplicable,
-                        );
-                    },
-                    // one of the operands is a symbol string
-                    [(expr, Some(symbol)), _] | [_, (expr, Some(symbol))] => {
-                        // creating an owned string for comparison
-                        if matches!(symbol, SymbolStrExpr::Expr { is_to_owned: true, .. }) {
-                            span_lint_and_sugg(
-                                cx,
-                                UNNECESSARY_SYMBOL_STR,
-                                expr.span,
-                                "unnecessary string allocation",
-                                "try",
-                                format!("{}.as_str()", symbol.as_symbol_snippet(cx)),
-                                Applicability::MachineApplicable,
-                            );
-                        }
-                    },
-                    // nothing found
-                    [(_, None), (_, None)] => {},
-                }
-            }
-        }
-    }
-}
-
-impl InterningDefinedSymbol {
-    fn symbol_str_expr<'tcx>(&self, expr: &'tcx Expr<'tcx>, cx: &LateContext<'tcx>) -> Option<SymbolStrExpr<'tcx>> {
-        static IDENT_STR_PATHS: &[&[&str]] = &[&paths::IDENT_AS_STR, &paths::TO_STRING_METHOD];
-        static SYMBOL_STR_PATHS: &[&[&str]] = &[
-            &paths::SYMBOL_AS_STR,
-            &paths::SYMBOL_TO_IDENT_STRING,
-            &paths::TO_STRING_METHOD,
-        ];
-        let call = if_chain! {
-            if let ExprKind::AddrOf(_, _, e) = expr.kind;
-            if let ExprKind::Unary(UnOp::Deref, e) = e.kind;
-            then { e } else { expr }
-        };
-        if_chain! {
-            // is a method call
-            if let ExprKind::MethodCall(_, item, [], _) = call.kind;
-            if let Some(did) = cx.typeck_results().type_dependent_def_id(call.hir_id);
-            let ty = cx.typeck_results().expr_ty(item);
-            // ...on either an Ident or a Symbol
-            if let Some(is_ident) = if match_type(cx, ty, &paths::SYMBOL) {
-                Some(false)
-            } else if match_type(cx, ty, &paths::IDENT) {
-                Some(true)
-            } else {
-                None
-            };
-            // ...which converts it to a string
-            let paths = if is_ident { IDENT_STR_PATHS } else { SYMBOL_STR_PATHS };
-            if let Some(path) = paths.iter().find(|path| match_def_path(cx, did, path));
-            then {
-                let is_to_owned = path.last().unwrap().ends_with("string");
-                return Some(SymbolStrExpr::Expr {
-                    item,
-                    is_ident,
-                    is_to_owned,
-                });
-            }
-        }
-        // is a string constant
-        if let Some(Constant::Str(s)) = constant_simple(cx, cx.typeck_results(), expr) {
-            let value = Symbol::intern(&s).as_u32();
-            // ...which matches a symbol constant
-            if let Some(&def_id) = self.symbol_map.get(&value) {
-                return Some(SymbolStrExpr::Const(def_id));
-            }
-        }
-        None
-    }
-}
-
-enum SymbolStrExpr<'tcx> {
-    /// a string constant with a corresponding symbol constant
-    Const(DefId),
-    /// a "symbol to string" expression like `symbol.as_str()`
-    Expr {
-        /// part that evaluates to `Symbol` or `Ident`
-        item: &'tcx Expr<'tcx>,
-        is_ident: bool,
-        /// whether an owned `String` is created like `to_ident_string()`
-        is_to_owned: bool,
-    },
-}
-
-impl<'tcx> SymbolStrExpr<'tcx> {
-    /// Returns a snippet that evaluates to a `Symbol` and is const if possible
-    fn as_symbol_snippet(&self, cx: &LateContext<'_>) -> Cow<'tcx, str> {
-        match *self {
-            Self::Const(def_id) => cx.tcx.def_path_str(def_id).into(),
-            Self::Expr { item, is_ident, .. } => {
-                let mut snip = snippet(cx, item.span.source_callsite(), "..");
-                if is_ident {
-                    // get `Ident.name`
-                    snip.to_mut().push_str(".name");
-                }
-                snip
-            },
-        }
-    }
-}
-
-declare_lint_pass!(IfChainStyle => [IF_CHAIN_STYLE]);
-
-impl<'tcx> LateLintPass<'tcx> for IfChainStyle {
-    fn check_block(&mut self, cx: &LateContext<'tcx>, block: &'tcx hir::Block<'_>) {
-        let (local, after, if_chain_span) = if_chain! {
-            if let [Stmt { kind: StmtKind::Local(local), .. }, after @ ..] = block.stmts;
-            if let Some(if_chain_span) = is_expn_of(block.span, "if_chain");
-            then { (local, after, if_chain_span) } else { return }
-        };
-        if is_first_if_chain_expr(cx, block.hir_id, if_chain_span) {
-            span_lint(
-                cx,
-                IF_CHAIN_STYLE,
-                if_chain_local_span(cx, local, if_chain_span),
-                "`let` expression should be above the `if_chain!`",
-            );
-        } else if local.span.ctxt() == block.span.ctxt() && is_if_chain_then(after, block.expr, if_chain_span) {
-            span_lint(
-                cx,
-                IF_CHAIN_STYLE,
-                if_chain_local_span(cx, local, if_chain_span),
-                "`let` expression should be inside `then { .. }`",
-            );
-        }
-    }
-
-    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>) {
-        let (cond, then, els) = if let Some(higher::IfOrIfLet { cond, r#else, then }) = higher::IfOrIfLet::hir(expr) {
-            (cond, then, r#else.is_some())
-        } else {
-            return;
-        };
-        let then_block = match then.kind {
-            ExprKind::Block(block, _) => block,
-            _ => return,
-        };
-        let if_chain_span = is_expn_of(expr.span, "if_chain");
-        if !els {
-            check_nested_if_chains(cx, expr, then_block, if_chain_span);
-        }
-        let if_chain_span = match if_chain_span {
-            None => return,
-            Some(span) => span,
-        };
-        // check for `if a && b;`
-        if_chain! {
-            if let ExprKind::Binary(op, _, _) = cond.kind;
-            if op.node == BinOpKind::And;
-            if cx.sess().source_map().is_multiline(cond.span);
-            then {
-                span_lint(cx, IF_CHAIN_STYLE, cond.span, "`if a && b;` should be `if a; if b;`");
-            }
-        }
-        if is_first_if_chain_expr(cx, expr.hir_id, if_chain_span)
-            && is_if_chain_then(then_block.stmts, then_block.expr, if_chain_span)
-        {
-            span_lint(cx, IF_CHAIN_STYLE, expr.span, "`if_chain!` only has one `if`");
-        }
-    }
-}
-
-fn check_nested_if_chains(
-    cx: &LateContext<'_>,
-    if_expr: &Expr<'_>,
-    then_block: &Block<'_>,
-    if_chain_span: Option<Span>,
-) {
-    #[rustfmt::skip]
-    let (head, tail) = match *then_block {
-        Block { stmts, expr: Some(tail), .. } => (stmts, tail),
-        Block {
-            stmts: &[
-                ref head @ ..,
-                Stmt { kind: StmtKind::Expr(tail) | StmtKind::Semi(tail), .. }
-            ],
-            ..
-        } => (head, tail),
-        _ => return,
-    };
-    if_chain! {
-        if let Some(higher::IfOrIfLet { r#else: None, .. }) = higher::IfOrIfLet::hir(tail);
-        let sm = cx.sess().source_map();
-        if head
-            .iter()
-            .all(|stmt| matches!(stmt.kind, StmtKind::Local(..)) && !sm.is_multiline(stmt.span));
-        if if_chain_span.is_some() || !is_else_clause(cx.tcx, if_expr);
-        then {} else { return }
-    }
-    let (span, msg) = match (if_chain_span, is_expn_of(tail.span, "if_chain")) {
-        (None, Some(_)) => (if_expr.span, "this `if` can be part of the inner `if_chain!`"),
-        (Some(_), None) => (tail.span, "this `if` can be part of the outer `if_chain!`"),
-        (Some(a), Some(b)) if a != b => (b, "this `if_chain!` can be merged with the outer `if_chain!`"),
-        _ => return,
-    };
-    span_lint_and_then(cx, IF_CHAIN_STYLE, span, msg, |diag| {
-        let (span, msg) = match head {
-            [] => return,
-            [stmt] => (stmt.span, "this `let` statement can also be in the `if_chain!`"),
-            [a, .., b] => (
-                a.span.to(b.span),
-                "these `let` statements can also be in the `if_chain!`",
-            ),
-        };
-        diag.span_help(span, msg);
-    });
-}
-
-fn is_first_if_chain_expr(cx: &LateContext<'_>, hir_id: HirId, if_chain_span: Span) -> bool {
-    cx.tcx
-        .hir()
-        .parent_iter(hir_id)
-        .find(|(_, node)| {
-            #[rustfmt::skip]
-            !matches!(node, Node::Expr(Expr { kind: ExprKind::Block(..), .. }) | Node::Stmt(_))
-        })
-        .map_or(false, |(id, _)| {
-            is_expn_of(cx.tcx.hir().span(id), "if_chain") != Some(if_chain_span)
-        })
-}
-
-/// Checks a trailing slice of statements and expression of a `Block` to see if they are part
-/// of the `then {..}` portion of an `if_chain!`
-fn is_if_chain_then(stmts: &[Stmt<'_>], expr: Option<&Expr<'_>>, if_chain_span: Span) -> bool {
-    let span = if let [stmt, ..] = stmts {
-        stmt.span
-    } else if let Some(expr) = expr {
-        expr.span
-    } else {
-        // empty `then {}`
-        return true;
-    };
-    is_expn_of(span, "if_chain").map_or(true, |span| span != if_chain_span)
-}
-
-/// Creates a `Span` for `let x = ..;` in an `if_chain!` call.
-fn if_chain_local_span(cx: &LateContext<'_>, local: &Local<'_>, if_chain_span: Span) -> Span {
-    let mut span = local.pat.span;
-    if let Some(init) = local.init {
-        span = span.to(init.span);
-    }
-    span.adjust(if_chain_span.ctxt().outer_expn());
-    let sm = cx.sess().source_map();
-    let span = sm.span_extend_to_prev_str(span, "let", false, true).unwrap_or(span);
-    let span = sm.span_extend_to_next_char(span, ';', false);
-    Span::new(
-        span.lo() - BytePos(3),
-        span.hi() + BytePos(1),
-        span.ctxt(),
-        span.parent(),
-    )
-}
-
-declare_lint_pass!(MsrvAttrImpl => [MISSING_MSRV_ATTR_IMPL]);
-
-impl LateLintPass<'_> for MsrvAttrImpl {
-    fn check_item(&mut self, cx: &LateContext<'_>, item: &hir::Item<'_>) {
-        if_chain! {
-            if let hir::ItemKind::Impl(hir::Impl {
-                of_trait: Some(lint_pass_trait_ref),
-                self_ty,
-                items,
-                ..
-            }) = &item.kind;
-            if let Some(lint_pass_trait_def_id) = lint_pass_trait_ref.trait_def_id();
-            let is_late_pass = match_def_path(cx, lint_pass_trait_def_id, &paths::LATE_LINT_PASS);
-            if is_late_pass || match_def_path(cx, lint_pass_trait_def_id, &paths::EARLY_LINT_PASS);
-            let self_ty = hir_ty_to_ty(cx.tcx, self_ty);
-            if let ty::Adt(self_ty_def, _) = self_ty.kind();
-            if self_ty_def.is_struct();
-            if self_ty_def.all_fields().any(|f| {
-                cx.tcx
-                    .type_of(f.did)
-                    .walk()
-                    .filter(|t| matches!(t.unpack(), GenericArgKind::Type(_)))
-                    .any(|t| match_type(cx, t.expect_ty(), &paths::RUSTC_VERSION))
-            });
-            if !items.iter().any(|item| item.ident.name == sym!(enter_lint_attrs));
-            then {
-                let context = if is_late_pass { "LateContext" } else { "EarlyContext" };
-                let lint_pass = if is_late_pass { "LateLintPass" } else { "EarlyLintPass" };
-                let span = cx.sess().source_map().span_through_char(item.span, '{');
-                span_lint_and_sugg(
-                    cx,
-                    MISSING_MSRV_ATTR_IMPL,
-                    span,
-                    &format!("`extract_msrv_attr!` macro missing from `{lint_pass}` implementation"),
-                    &format!("add `extract_msrv_attr!({context})` to the `{lint_pass}` implementation"),
-                    format!("{}\n    extract_msrv_attr!({context});", snippet(cx, span, "..")),
-                    Applicability::MachineApplicable,
-                );
-            }
-        }
-    }
-}
+pub mod msrv_attr_impl;
+pub mod outer_expn_data_pass;
+pub mod produce_ice;
+pub mod unnecessary_def_path;
diff --git a/src/tools/clippy/clippy_lints/src/utils/internal_lints/clippy_lints_internal.rs b/src/tools/clippy/clippy_lints/src/utils/internal_lints/clippy_lints_internal.rs
new file mode 100644
index 000000000000..da9514dd15ee
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/utils/internal_lints/clippy_lints_internal.rs
@@ -0,0 +1,49 @@
+use clippy_utils::diagnostics::span_lint;
+use rustc_ast::ast::{Crate, ItemKind, ModKind};
+use rustc_lint::{EarlyContext, EarlyLintPass};
+use rustc_session::{declare_lint_pass, declare_tool_lint};
+
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks for various things we like to keep tidy in clippy.
+    ///
+    /// ### Why is this bad?
+    /// We like to pretend we're an example of tidy code.
+    ///
+    /// ### Example
+    /// Wrong ordering of the util::paths constants.
+    pub CLIPPY_LINTS_INTERNAL,
+    internal,
+    "various things that will negatively affect your clippy experience"
+}
+
+declare_lint_pass!(ClippyLintsInternal => [CLIPPY_LINTS_INTERNAL]);
+
+impl EarlyLintPass for ClippyLintsInternal {
+    fn check_crate(&mut self, cx: &EarlyContext<'_>, krate: &Crate) {
+        if let Some(utils) = krate.items.iter().find(|item| item.ident.name.as_str() == "utils") {
+            if let ItemKind::Mod(_, ModKind::Loaded(ref items, ..)) = utils.kind {
+                if let Some(paths) = items.iter().find(|item| item.ident.name.as_str() == "paths") {
+                    if let ItemKind::Mod(_, ModKind::Loaded(ref items, ..)) = paths.kind {
+                        let mut last_name: Option<&str> = None;
+                        for item in items {
+                            let name = item.ident.as_str();
+                            if let Some(last_name) = last_name {
+                                if *last_name > *name {
+                                    span_lint(
+                                        cx,
+                                        CLIPPY_LINTS_INTERNAL,
+                                        item.span,
+                                        "this constant should be before the previous constant due to lexical \
+                                         ordering",
+                                    );
+                                }
+                            }
+                            last_name = Some(name);
+                        }
+                    }
+                }
+            }
+        }
+    }
+}
diff --git a/src/tools/clippy/clippy_lints/src/utils/internal_lints/collapsible_calls.rs b/src/tools/clippy/clippy_lints/src/utils/internal_lints/collapsible_calls.rs
new file mode 100644
index 000000000000..d7666b77f6e9
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/utils/internal_lints/collapsible_calls.rs
@@ -0,0 +1,245 @@
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::source::snippet;
+use clippy_utils::{is_expr_path_def_path, is_lint_allowed, peel_blocks_with_stmt, SpanlessEq};
+use if_chain::if_chain;
+use rustc_errors::Applicability;
+use rustc_hir as hir;
+use rustc_hir::{Closure, Expr, ExprKind};
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_session::{declare_lint_pass, declare_tool_lint};
+
+use std::borrow::{Borrow, Cow};
+
+declare_clippy_lint! {
+    /// ### What it does
+    /// Lints `span_lint_and_then` function calls, where the
+    /// closure argument has only one statement and that statement is a method
+    /// call to `span_suggestion`, `span_help`, `span_note` (using the same
+    /// span), `help` or `note`.
+    ///
+    /// These usages of `span_lint_and_then` should be replaced with one of the
+    /// wrapper functions `span_lint_and_sugg`, span_lint_and_help`, or
+    /// `span_lint_and_note`.
+    ///
+    /// ### Why is this bad?
+    /// Using the wrapper `span_lint_and_*` functions, is more
+    /// convenient, readable and less error prone.
+    ///
+    /// ### Example
+    /// ```rust,ignore
+    /// span_lint_and_then(cx, TEST_LINT, expr.span, lint_msg, |diag| {
+    ///     diag.span_suggestion(
+    ///         expr.span,
+    ///         help_msg,
+    ///         sugg.to_string(),
+    ///         Applicability::MachineApplicable,
+    ///     );
+    /// });
+    /// span_lint_and_then(cx, TEST_LINT, expr.span, lint_msg, |diag| {
+    ///     diag.span_help(expr.span, help_msg);
+    /// });
+    /// span_lint_and_then(cx, TEST_LINT, expr.span, lint_msg, |diag| {
+    ///     diag.help(help_msg);
+    /// });
+    /// span_lint_and_then(cx, TEST_LINT, expr.span, lint_msg, |diag| {
+    ///     diag.span_note(expr.span, note_msg);
+    /// });
+    /// span_lint_and_then(cx, TEST_LINT, expr.span, lint_msg, |diag| {
+    ///     diag.note(note_msg);
+    /// });
+    /// ```
+    ///
+    /// Use instead:
+    /// ```rust,ignore
+    /// span_lint_and_sugg(
+    ///     cx,
+    ///     TEST_LINT,
+    ///     expr.span,
+    ///     lint_msg,
+    ///     help_msg,
+    ///     sugg.to_string(),
+    ///     Applicability::MachineApplicable,
+    /// );
+    /// span_lint_and_help(cx, TEST_LINT, expr.span, lint_msg, Some(expr.span), help_msg);
+    /// span_lint_and_help(cx, TEST_LINT, expr.span, lint_msg, None, help_msg);
+    /// span_lint_and_note(cx, TEST_LINT, expr.span, lint_msg, Some(expr.span), note_msg);
+    /// span_lint_and_note(cx, TEST_LINT, expr.span, lint_msg, None, note_msg);
+    /// ```
+    pub COLLAPSIBLE_SPAN_LINT_CALLS,
+    internal,
+    "found collapsible `span_lint_and_then` calls"
+}
+
+declare_lint_pass!(CollapsibleCalls => [COLLAPSIBLE_SPAN_LINT_CALLS]);
+
+impl<'tcx> LateLintPass<'tcx> for CollapsibleCalls {
+    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>) {
+        if is_lint_allowed(cx, COLLAPSIBLE_SPAN_LINT_CALLS, expr.hir_id) {
+            return;
+        }
+
+        if_chain! {
+            if let ExprKind::Call(func, and_then_args) = expr.kind;
+            if is_expr_path_def_path(cx, func, &["clippy_utils", "diagnostics", "span_lint_and_then"]);
+            if and_then_args.len() == 5;
+            if let ExprKind::Closure(&Closure { body, .. }) = &and_then_args[4].kind;
+            let body = cx.tcx.hir().body(body);
+            let only_expr = peel_blocks_with_stmt(body.value);
+            if let ExprKind::MethodCall(ps, recv, span_call_args, _) = &only_expr.kind;
+            if let ExprKind::Path(..) = recv.kind;
+            then {
+                let and_then_snippets = get_and_then_snippets(cx, and_then_args);
+                let mut sle = SpanlessEq::new(cx).deny_side_effects();
+                match ps.ident.as_str() {
+                    "span_suggestion" if sle.eq_expr(&and_then_args[2], &span_call_args[0]) => {
+                        suggest_suggestion(
+                            cx,
+                            expr,
+                            &and_then_snippets,
+                            &span_suggestion_snippets(cx, span_call_args),
+                        );
+                    },
+                    "span_help" if sle.eq_expr(&and_then_args[2], &span_call_args[0]) => {
+                        let help_snippet = snippet(cx, span_call_args[1].span, r#""...""#);
+                        suggest_help(cx, expr, &and_then_snippets, help_snippet.borrow(), true);
+                    },
+                    "span_note" if sle.eq_expr(&and_then_args[2], &span_call_args[0]) => {
+                        let note_snippet = snippet(cx, span_call_args[1].span, r#""...""#);
+                        suggest_note(cx, expr, &and_then_snippets, note_snippet.borrow(), true);
+                    },
+                    "help" => {
+                        let help_snippet = snippet(cx, span_call_args[0].span, r#""...""#);
+                        suggest_help(cx, expr, &and_then_snippets, help_snippet.borrow(), false);
+                    },
+                    "note" => {
+                        let note_snippet = snippet(cx, span_call_args[0].span, r#""...""#);
+                        suggest_note(cx, expr, &and_then_snippets, note_snippet.borrow(), false);
+                    },
+                    _ => (),
+                }
+            }
+        }
+    }
+}
+
+struct AndThenSnippets<'a> {
+    cx: Cow<'a, str>,
+    lint: Cow<'a, str>,
+    span: Cow<'a, str>,
+    msg: Cow<'a, str>,
+}
+
+fn get_and_then_snippets<'a, 'hir>(cx: &LateContext<'_>, and_then_snippets: &'hir [Expr<'hir>]) -> AndThenSnippets<'a> {
+    let cx_snippet = snippet(cx, and_then_snippets[0].span, "cx");
+    let lint_snippet = snippet(cx, and_then_snippets[1].span, "..");
+    let span_snippet = snippet(cx, and_then_snippets[2].span, "span");
+    let msg_snippet = snippet(cx, and_then_snippets[3].span, r#""...""#);
+
+    AndThenSnippets {
+        cx: cx_snippet,
+        lint: lint_snippet,
+        span: span_snippet,
+        msg: msg_snippet,
+    }
+}
+
+struct SpanSuggestionSnippets<'a> {
+    help: Cow<'a, str>,
+    sugg: Cow<'a, str>,
+    applicability: Cow<'a, str>,
+}
+
+fn span_suggestion_snippets<'a, 'hir>(
+    cx: &LateContext<'_>,
+    span_call_args: &'hir [Expr<'hir>],
+) -> SpanSuggestionSnippets<'a> {
+    let help_snippet = snippet(cx, span_call_args[1].span, r#""...""#);
+    let sugg_snippet = snippet(cx, span_call_args[2].span, "..");
+    let applicability_snippet = snippet(cx, span_call_args[3].span, "Applicability::MachineApplicable");
+
+    SpanSuggestionSnippets {
+        help: help_snippet,
+        sugg: sugg_snippet,
+        applicability: applicability_snippet,
+    }
+}
+
+fn suggest_suggestion(
+    cx: &LateContext<'_>,
+    expr: &Expr<'_>,
+    and_then_snippets: &AndThenSnippets<'_>,
+    span_suggestion_snippets: &SpanSuggestionSnippets<'_>,
+) {
+    span_lint_and_sugg(
+        cx,
+        COLLAPSIBLE_SPAN_LINT_CALLS,
+        expr.span,
+        "this call is collapsible",
+        "collapse into",
+        format!(
+            "span_lint_and_sugg({}, {}, {}, {}, {}, {}, {})",
+            and_then_snippets.cx,
+            and_then_snippets.lint,
+            and_then_snippets.span,
+            and_then_snippets.msg,
+            span_suggestion_snippets.help,
+            span_suggestion_snippets.sugg,
+            span_suggestion_snippets.applicability
+        ),
+        Applicability::MachineApplicable,
+    );
+}
+
+fn suggest_help(
+    cx: &LateContext<'_>,
+    expr: &Expr<'_>,
+    and_then_snippets: &AndThenSnippets<'_>,
+    help: &str,
+    with_span: bool,
+) {
+    let option_span = if with_span {
+        format!("Some({})", and_then_snippets.span)
+    } else {
+        "None".to_string()
+    };
+
+    span_lint_and_sugg(
+        cx,
+        COLLAPSIBLE_SPAN_LINT_CALLS,
+        expr.span,
+        "this call is collapsible",
+        "collapse into",
+        format!(
+            "span_lint_and_help({}, {}, {}, {}, {}, {help})",
+            and_then_snippets.cx, and_then_snippets.lint, and_then_snippets.span, and_then_snippets.msg, &option_span,
+        ),
+        Applicability::MachineApplicable,
+    );
+}
+
+fn suggest_note(
+    cx: &LateContext<'_>,
+    expr: &Expr<'_>,
+    and_then_snippets: &AndThenSnippets<'_>,
+    note: &str,
+    with_span: bool,
+) {
+    let note_span = if with_span {
+        format!("Some({})", and_then_snippets.span)
+    } else {
+        "None".to_string()
+    };
+
+    span_lint_and_sugg(
+        cx,
+        COLLAPSIBLE_SPAN_LINT_CALLS,
+        expr.span,
+        "this call is collapsible",
+        "collapse into",
+        format!(
+            "span_lint_and_note({}, {}, {}, {}, {note_span}, {note})",
+            and_then_snippets.cx, and_then_snippets.lint, and_then_snippets.span, and_then_snippets.msg,
+        ),
+        Applicability::MachineApplicable,
+    );
+}
diff --git a/src/tools/clippy/clippy_lints/src/utils/internal_lints/compiler_lint_functions.rs b/src/tools/clippy/clippy_lints/src/utils/internal_lints/compiler_lint_functions.rs
new file mode 100644
index 000000000000..cacd05262a21
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/utils/internal_lints/compiler_lint_functions.rs
@@ -0,0 +1,77 @@
+use clippy_utils::diagnostics::span_lint_and_help;
+use clippy_utils::ty::match_type;
+use clippy_utils::{is_lint_allowed, paths};
+use if_chain::if_chain;
+use rustc_data_structures::fx::FxHashMap;
+use rustc_hir::{Expr, ExprKind};
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_session::{declare_tool_lint, impl_lint_pass};
+
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks for calls to `cx.span_lint*` and suggests to use the `utils::*`
+    /// variant of the function.
+    ///
+    /// ### Why is this bad?
+    /// The `utils::*` variants also add a link to the Clippy documentation to the
+    /// warning/error messages.
+    ///
+    /// ### Example
+    /// ```rust,ignore
+    /// cx.span_lint(LINT_NAME, "message");
+    /// ```
+    ///
+    /// Use instead:
+    /// ```rust,ignore
+    /// utils::span_lint(cx, LINT_NAME, "message");
+    /// ```
+    pub COMPILER_LINT_FUNCTIONS,
+    internal,
+    "usage of the lint functions of the compiler instead of the utils::* variant"
+}
+
+impl_lint_pass!(CompilerLintFunctions => [COMPILER_LINT_FUNCTIONS]);
+
+#[derive(Clone, Default)]
+pub struct CompilerLintFunctions {
+    map: FxHashMap<&'static str, &'static str>,
+}
+
+impl CompilerLintFunctions {
+    #[must_use]
+    pub fn new() -> Self {
+        let mut map = FxHashMap::default();
+        map.insert("span_lint", "utils::span_lint");
+        map.insert("struct_span_lint", "utils::span_lint");
+        map.insert("lint", "utils::span_lint");
+        map.insert("span_lint_note", "utils::span_lint_and_note");
+        map.insert("span_lint_help", "utils::span_lint_and_help");
+        Self { map }
+    }
+}
+
+impl<'tcx> LateLintPass<'tcx> for CompilerLintFunctions {
+    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
+        if is_lint_allowed(cx, COMPILER_LINT_FUNCTIONS, expr.hir_id) {
+            return;
+        }
+
+        if_chain! {
+            if let ExprKind::MethodCall(path, self_arg, _, _) = &expr.kind;
+            let fn_name = path.ident;
+            if let Some(sugg) = self.map.get(fn_name.as_str());
+            let ty = cx.typeck_results().expr_ty(self_arg).peel_refs();
+            if match_type(cx, ty, &paths::EARLY_CONTEXT) || match_type(cx, ty, &paths::LATE_CONTEXT);
+            then {
+                span_lint_and_help(
+                    cx,
+                    COMPILER_LINT_FUNCTIONS,
+                    path.ident.span,
+                    "usage of a compiler lint function",
+                    None,
+                    &format!("please use the Clippy variant of this function: `{sugg}`"),
+                );
+            }
+        }
+    }
+}
diff --git a/src/tools/clippy/clippy_lints/src/utils/internal_lints/if_chain_style.rs b/src/tools/clippy/clippy_lints/src/utils/internal_lints/if_chain_style.rs
new file mode 100644
index 000000000000..883a5c08e5c1
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/utils/internal_lints/if_chain_style.rs
@@ -0,0 +1,164 @@
+use clippy_utils::diagnostics::{span_lint, span_lint_and_then};
+use clippy_utils::{higher, is_else_clause, is_expn_of};
+use if_chain::if_chain;
+use rustc_hir as hir;
+use rustc_hir::{BinOpKind, Block, Expr, ExprKind, HirId, Local, Node, Stmt, StmtKind};
+use rustc_lint::{LateContext, LateLintPass, LintContext};
+use rustc_session::{declare_lint_pass, declare_tool_lint};
+use rustc_span::{BytePos, Span};
+
+declare_clippy_lint! {
+    /// Finds unidiomatic usage of `if_chain!`
+    pub IF_CHAIN_STYLE,
+    internal,
+    "non-idiomatic `if_chain!` usage"
+}
+
+declare_lint_pass!(IfChainStyle => [IF_CHAIN_STYLE]);
+
+impl<'tcx> LateLintPass<'tcx> for IfChainStyle {
+    fn check_block(&mut self, cx: &LateContext<'tcx>, block: &'tcx hir::Block<'_>) {
+        let (local, after, if_chain_span) = if_chain! {
+            if let [Stmt { kind: StmtKind::Local(local), .. }, after @ ..] = block.stmts;
+            if let Some(if_chain_span) = is_expn_of(block.span, "if_chain");
+            then { (local, after, if_chain_span) } else { return }
+        };
+        if is_first_if_chain_expr(cx, block.hir_id, if_chain_span) {
+            span_lint(
+                cx,
+                IF_CHAIN_STYLE,
+                if_chain_local_span(cx, local, if_chain_span),
+                "`let` expression should be above the `if_chain!`",
+            );
+        } else if local.span.ctxt() == block.span.ctxt() && is_if_chain_then(after, block.expr, if_chain_span) {
+            span_lint(
+                cx,
+                IF_CHAIN_STYLE,
+                if_chain_local_span(cx, local, if_chain_span),
+                "`let` expression should be inside `then { .. }`",
+            );
+        }
+    }
+
+    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>) {
+        let (cond, then, els) = if let Some(higher::IfOrIfLet { cond, r#else, then }) = higher::IfOrIfLet::hir(expr) {
+            (cond, then, r#else.is_some())
+        } else {
+            return;
+        };
+        let ExprKind::Block(then_block, _) = then.kind else { return };
+        let if_chain_span = is_expn_of(expr.span, "if_chain");
+        if !els {
+            check_nested_if_chains(cx, expr, then_block, if_chain_span);
+        }
+        let Some(if_chain_span) = if_chain_span else { return };
+        // check for `if a && b;`
+        if_chain! {
+            if let ExprKind::Binary(op, _, _) = cond.kind;
+            if op.node == BinOpKind::And;
+            if cx.sess().source_map().is_multiline(cond.span);
+            then {
+                span_lint(cx, IF_CHAIN_STYLE, cond.span, "`if a && b;` should be `if a; if b;`");
+            }
+        }
+        if is_first_if_chain_expr(cx, expr.hir_id, if_chain_span)
+            && is_if_chain_then(then_block.stmts, then_block.expr, if_chain_span)
+        {
+            span_lint(cx, IF_CHAIN_STYLE, expr.span, "`if_chain!` only has one `if`");
+        }
+    }
+}
+
+fn check_nested_if_chains(
+    cx: &LateContext<'_>,
+    if_expr: &Expr<'_>,
+    then_block: &Block<'_>,
+    if_chain_span: Option<Span>,
+) {
+    #[rustfmt::skip]
+    let (head, tail) = match *then_block {
+        Block { stmts, expr: Some(tail), .. } => (stmts, tail),
+        Block {
+            stmts: &[
+                ref head @ ..,
+                Stmt { kind: StmtKind::Expr(tail) | StmtKind::Semi(tail), .. }
+            ],
+            ..
+        } => (head, tail),
+        _ => return,
+    };
+    if_chain! {
+        if let Some(higher::IfOrIfLet { r#else: None, .. }) = higher::IfOrIfLet::hir(tail);
+        let sm = cx.sess().source_map();
+        if head
+            .iter()
+            .all(|stmt| matches!(stmt.kind, StmtKind::Local(..)) && !sm.is_multiline(stmt.span));
+        if if_chain_span.is_some() || !is_else_clause(cx.tcx, if_expr);
+        then {
+        } else {
+            return;
+        }
+    }
+    let (span, msg) = match (if_chain_span, is_expn_of(tail.span, "if_chain")) {
+        (None, Some(_)) => (if_expr.span, "this `if` can be part of the inner `if_chain!`"),
+        (Some(_), None) => (tail.span, "this `if` can be part of the outer `if_chain!`"),
+        (Some(a), Some(b)) if a != b => (b, "this `if_chain!` can be merged with the outer `if_chain!`"),
+        _ => return,
+    };
+    span_lint_and_then(cx, IF_CHAIN_STYLE, span, msg, |diag| {
+        let (span, msg) = match head {
+            [] => return,
+            [stmt] => (stmt.span, "this `let` statement can also be in the `if_chain!`"),
+            [a, .., b] => (
+                a.span.to(b.span),
+                "these `let` statements can also be in the `if_chain!`",
+            ),
+        };
+        diag.span_help(span, msg);
+    });
+}
+
+fn is_first_if_chain_expr(cx: &LateContext<'_>, hir_id: HirId, if_chain_span: Span) -> bool {
+    cx.tcx
+        .hir()
+        .parent_iter(hir_id)
+        .find(|(_, node)| {
+            #[rustfmt::skip]
+            !matches!(node, Node::Expr(Expr { kind: ExprKind::Block(..), .. }) | Node::Stmt(_))
+        })
+        .map_or(false, |(id, _)| {
+            is_expn_of(cx.tcx.hir().span(id), "if_chain") != Some(if_chain_span)
+        })
+}
+
+/// Checks a trailing slice of statements and expression of a `Block` to see if they are part
+/// of the `then {..}` portion of an `if_chain!`
+fn is_if_chain_then(stmts: &[Stmt<'_>], expr: Option<&Expr<'_>>, if_chain_span: Span) -> bool {
+    let span = if let [stmt, ..] = stmts {
+        stmt.span
+    } else if let Some(expr) = expr {
+        expr.span
+    } else {
+        // empty `then {}`
+        return true;
+    };
+    is_expn_of(span, "if_chain").map_or(true, |span| span != if_chain_span)
+}
+
+/// Creates a `Span` for `let x = ..;` in an `if_chain!` call.
+fn if_chain_local_span(cx: &LateContext<'_>, local: &Local<'_>, if_chain_span: Span) -> Span {
+    let mut span = local.pat.span;
+    if let Some(init) = local.init {
+        span = span.to(init.span);
+    }
+    span.adjust(if_chain_span.ctxt().outer_expn());
+    let sm = cx.sess().source_map();
+    let span = sm.span_extend_to_prev_str(span, "let", false, true).unwrap_or(span);
+    let span = sm.span_extend_to_next_char(span, ';', false);
+    Span::new(
+        span.lo() - BytePos(3),
+        span.hi() + BytePos(1),
+        span.ctxt(),
+        span.parent(),
+    )
+}
diff --git a/src/tools/clippy/clippy_lints/src/utils/internal_lints/interning_defined_symbol.rs b/src/tools/clippy/clippy_lints/src/utils/internal_lints/interning_defined_symbol.rs
new file mode 100644
index 000000000000..096b601572b4
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/utils/internal_lints/interning_defined_symbol.rs
@@ -0,0 +1,239 @@
+use clippy_utils::consts::{constant_simple, Constant};
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::source::snippet;
+use clippy_utils::ty::match_type;
+use clippy_utils::{def_path_res, is_expn_of, match_def_path, paths};
+use if_chain::if_chain;
+use rustc_data_structures::fx::FxHashMap;
+use rustc_errors::Applicability;
+use rustc_hir::def::{DefKind, Res};
+use rustc_hir::def_id::DefId;
+use rustc_hir::{BinOpKind, Expr, ExprKind, UnOp};
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_middle::mir::interpret::ConstValue;
+use rustc_middle::ty::{self};
+use rustc_session::{declare_tool_lint, impl_lint_pass};
+use rustc_span::symbol::Symbol;
+
+use std::borrow::Cow;
+
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks for interning symbols that have already been pre-interned and defined as constants.
+    ///
+    /// ### Why is this bad?
+    /// It's faster and easier to use the symbol constant.
+    ///
+    /// ### Example
+    /// ```rust,ignore
+    /// let _ = sym!(f32);
+    /// ```
+    ///
+    /// Use instead:
+    /// ```rust,ignore
+    /// let _ = sym::f32;
+    /// ```
+    pub INTERNING_DEFINED_SYMBOL,
+    internal,
+    "interning a symbol that is pre-interned and defined as a constant"
+}
+
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks for unnecessary conversion from Symbol to a string.
+    ///
+    /// ### Why is this bad?
+    /// It's faster use symbols directly instead of strings.
+    ///
+    /// ### Example
+    /// ```rust,ignore
+    /// symbol.as_str() == "clippy";
+    /// ```
+    ///
+    /// Use instead:
+    /// ```rust,ignore
+    /// symbol == sym::clippy;
+    /// ```
+    pub UNNECESSARY_SYMBOL_STR,
+    internal,
+    "unnecessary conversion between Symbol and string"
+}
+
+#[derive(Default)]
+pub struct InterningDefinedSymbol {
+    // Maps the symbol value to the constant DefId.
+    symbol_map: FxHashMap<u32, DefId>,
+}
+
+impl_lint_pass!(InterningDefinedSymbol => [INTERNING_DEFINED_SYMBOL, UNNECESSARY_SYMBOL_STR]);
+
+impl<'tcx> LateLintPass<'tcx> for InterningDefinedSymbol {
+    fn check_crate(&mut self, cx: &LateContext<'_>) {
+        if !self.symbol_map.is_empty() {
+            return;
+        }
+
+        for &module in &[&paths::KW_MODULE, &paths::SYM_MODULE] {
+            if let Some(def_id) = def_path_res(cx, module, None).opt_def_id() {
+                for item in cx.tcx.module_children(def_id).iter() {
+                    if_chain! {
+                        if let Res::Def(DefKind::Const, item_def_id) = item.res;
+                        let ty = cx.tcx.type_of(item_def_id);
+                        if match_type(cx, ty, &paths::SYMBOL);
+                        if let Ok(ConstValue::Scalar(value)) = cx.tcx.const_eval_poly(item_def_id);
+                        if let Ok(value) = value.to_u32();
+                        then {
+                            self.symbol_map.insert(value, item_def_id);
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
+        if_chain! {
+            if let ExprKind::Call(func, [arg]) = &expr.kind;
+            if let ty::FnDef(def_id, _) = cx.typeck_results().expr_ty(func).kind();
+            if match_def_path(cx, *def_id, &paths::SYMBOL_INTERN);
+            if let Some(Constant::Str(arg)) = constant_simple(cx, cx.typeck_results(), arg);
+            let value = Symbol::intern(&arg).as_u32();
+            if let Some(&def_id) = self.symbol_map.get(&value);
+            then {
+                span_lint_and_sugg(
+                    cx,
+                    INTERNING_DEFINED_SYMBOL,
+                    is_expn_of(expr.span, "sym").unwrap_or(expr.span),
+                    "interning a defined symbol",
+                    "try",
+                    cx.tcx.def_path_str(def_id),
+                    Applicability::MachineApplicable,
+                );
+            }
+        }
+        if let ExprKind::Binary(op, left, right) = expr.kind {
+            if matches!(op.node, BinOpKind::Eq | BinOpKind::Ne) {
+                let data = [
+                    (left, self.symbol_str_expr(left, cx)),
+                    (right, self.symbol_str_expr(right, cx)),
+                ];
+                match data {
+                    // both operands are a symbol string
+                    [(_, Some(left)), (_, Some(right))] => {
+                        span_lint_and_sugg(
+                            cx,
+                            UNNECESSARY_SYMBOL_STR,
+                            expr.span,
+                            "unnecessary `Symbol` to string conversion",
+                            "try",
+                            format!(
+                                "{} {} {}",
+                                left.as_symbol_snippet(cx),
+                                op.node.as_str(),
+                                right.as_symbol_snippet(cx),
+                            ),
+                            Applicability::MachineApplicable,
+                        );
+                    },
+                    // one of the operands is a symbol string
+                    [(expr, Some(symbol)), _] | [_, (expr, Some(symbol))] => {
+                        // creating an owned string for comparison
+                        if matches!(symbol, SymbolStrExpr::Expr { is_to_owned: true, .. }) {
+                            span_lint_and_sugg(
+                                cx,
+                                UNNECESSARY_SYMBOL_STR,
+                                expr.span,
+                                "unnecessary string allocation",
+                                "try",
+                                format!("{}.as_str()", symbol.as_symbol_snippet(cx)),
+                                Applicability::MachineApplicable,
+                            );
+                        }
+                    },
+                    // nothing found
+                    [(_, None), (_, None)] => {},
+                }
+            }
+        }
+    }
+}
+
+impl InterningDefinedSymbol {
+    fn symbol_str_expr<'tcx>(&self, expr: &'tcx Expr<'tcx>, cx: &LateContext<'tcx>) -> Option<SymbolStrExpr<'tcx>> {
+        static IDENT_STR_PATHS: &[&[&str]] = &[&paths::IDENT_AS_STR, &paths::TO_STRING_METHOD];
+        static SYMBOL_STR_PATHS: &[&[&str]] = &[
+            &paths::SYMBOL_AS_STR,
+            &paths::SYMBOL_TO_IDENT_STRING,
+            &paths::TO_STRING_METHOD,
+        ];
+        let call = if_chain! {
+            if let ExprKind::AddrOf(_, _, e) = expr.kind;
+            if let ExprKind::Unary(UnOp::Deref, e) = e.kind;
+            then { e } else { expr }
+        };
+        if_chain! {
+            // is a method call
+            if let ExprKind::MethodCall(_, item, [], _) = call.kind;
+            if let Some(did) = cx.typeck_results().type_dependent_def_id(call.hir_id);
+            let ty = cx.typeck_results().expr_ty(item);
+            // ...on either an Ident or a Symbol
+            if let Some(is_ident) = if match_type(cx, ty, &paths::SYMBOL) {
+                Some(false)
+            } else if match_type(cx, ty, &paths::IDENT) {
+                Some(true)
+            } else {
+                None
+            };
+            // ...which converts it to a string
+            let paths = if is_ident { IDENT_STR_PATHS } else { SYMBOL_STR_PATHS };
+            if let Some(path) = paths.iter().find(|path| match_def_path(cx, did, path));
+            then {
+                let is_to_owned = path.last().unwrap().ends_with("string");
+                return Some(SymbolStrExpr::Expr {
+                    item,
+                    is_ident,
+                    is_to_owned,
+                });
+            }
+        }
+        // is a string constant
+        if let Some(Constant::Str(s)) = constant_simple(cx, cx.typeck_results(), expr) {
+            let value = Symbol::intern(&s).as_u32();
+            // ...which matches a symbol constant
+            if let Some(&def_id) = self.symbol_map.get(&value) {
+                return Some(SymbolStrExpr::Const(def_id));
+            }
+        }
+        None
+    }
+}
+
+enum SymbolStrExpr<'tcx> {
+    /// a string constant with a corresponding symbol constant
+    Const(DefId),
+    /// a "symbol to string" expression like `symbol.as_str()`
+    Expr {
+        /// part that evaluates to `Symbol` or `Ident`
+        item: &'tcx Expr<'tcx>,
+        is_ident: bool,
+        /// whether an owned `String` is created like `to_ident_string()`
+        is_to_owned: bool,
+    },
+}
+
+impl<'tcx> SymbolStrExpr<'tcx> {
+    /// Returns a snippet that evaluates to a `Symbol` and is const if possible
+    fn as_symbol_snippet(&self, cx: &LateContext<'_>) -> Cow<'tcx, str> {
+        match *self {
+            Self::Const(def_id) => cx.tcx.def_path_str(def_id).into(),
+            Self::Expr { item, is_ident, .. } => {
+                let mut snip = snippet(cx, item.span.source_callsite(), "..");
+                if is_ident {
+                    // get `Ident.name`
+                    snip.to_mut().push_str(".name");
+                }
+                snip
+            },
+        }
+    }
+}
diff --git a/src/tools/clippy/clippy_lints/src/utils/internal_lints/invalid_paths.rs b/src/tools/clippy/clippy_lints/src/utils/internal_lints/invalid_paths.rs
new file mode 100644
index 000000000000..25532dd4e268
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/utils/internal_lints/invalid_paths.rs
@@ -0,0 +1,108 @@
+use clippy_utils::consts::{constant_simple, Constant};
+use clippy_utils::def_path_res;
+use clippy_utils::diagnostics::span_lint;
+use if_chain::if_chain;
+use rustc_hir as hir;
+use rustc_hir::def::{DefKind, Res};
+use rustc_hir::Item;
+use rustc_hir_analysis::hir_ty_to_ty;
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_middle::ty::{self, fast_reject::SimplifiedTypeGen, FloatTy};
+use rustc_session::{declare_lint_pass, declare_tool_lint};
+use rustc_span::symbol::Symbol;
+
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks the paths module for invalid paths.
+    ///
+    /// ### Why is this bad?
+    /// It indicates a bug in the code.
+    ///
+    /// ### Example
+    /// None.
+    pub INVALID_PATHS,
+    internal,
+    "invalid path"
+}
+
+declare_lint_pass!(InvalidPaths => [INVALID_PATHS]);
+
+impl<'tcx> LateLintPass<'tcx> for InvalidPaths {
+    fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'_>) {
+        let local_def_id = &cx.tcx.parent_module(item.hir_id());
+        let mod_name = &cx.tcx.item_name(local_def_id.to_def_id());
+        if_chain! {
+            if mod_name.as_str() == "paths";
+            if let hir::ItemKind::Const(ty, body_id) = item.kind;
+            let ty = hir_ty_to_ty(cx.tcx, ty);
+            if let ty::Array(el_ty, _) = &ty.kind();
+            if let ty::Ref(_, el_ty, _) = &el_ty.kind();
+            if el_ty.is_str();
+            let body = cx.tcx.hir().body(body_id);
+            let typeck_results = cx.tcx.typeck_body(body_id);
+            if let Some(Constant::Vec(path)) = constant_simple(cx, typeck_results, body.value);
+            let path: Vec<&str> = path
+                .iter()
+                .map(|x| {
+                    if let Constant::Str(s) = x {
+                        s.as_str()
+                    } else {
+                        // We checked the type of the constant above
+                        unreachable!()
+                    }
+                })
+                .collect();
+            if !check_path(cx, &path[..]);
+            then {
+                span_lint(cx, INVALID_PATHS, item.span, "invalid path");
+            }
+        }
+    }
+}
+
+// This is not a complete resolver for paths. It works on all the paths currently used in the paths
+// module.  That's all it does and all it needs to do.
+pub fn check_path(cx: &LateContext<'_>, path: &[&str]) -> bool {
+    if def_path_res(cx, path, None) != Res::Err {
+        return true;
+    }
+
+    // Some implementations can't be found by `path_to_res`, particularly inherent
+    // implementations of native types. Check lang items.
+    let path_syms: Vec<_> = path.iter().map(|p| Symbol::intern(p)).collect();
+    let lang_items = cx.tcx.lang_items();
+    // This list isn't complete, but good enough for our current list of paths.
+    let incoherent_impls = [
+        SimplifiedTypeGen::FloatSimplifiedType(FloatTy::F32),
+        SimplifiedTypeGen::FloatSimplifiedType(FloatTy::F64),
+        SimplifiedTypeGen::SliceSimplifiedType,
+        SimplifiedTypeGen::StrSimplifiedType,
+    ]
+    .iter()
+    .flat_map(|&ty| cx.tcx.incoherent_impls(ty));
+    for item_def_id in lang_items.items().iter().flatten().chain(incoherent_impls) {
+        let lang_item_path = cx.get_def_path(*item_def_id);
+        if path_syms.starts_with(&lang_item_path) {
+            if let [item] = &path_syms[lang_item_path.len()..] {
+                if matches!(
+                    cx.tcx.def_kind(*item_def_id),
+                    DefKind::Mod | DefKind::Enum | DefKind::Trait
+                ) {
+                    for child in cx.tcx.module_children(*item_def_id) {
+                        if child.ident.name == *item {
+                            return true;
+                        }
+                    }
+                } else {
+                    for child in cx.tcx.associated_item_def_ids(*item_def_id) {
+                        if cx.tcx.item_name(*child) == *item {
+                            return true;
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    false
+}
diff --git a/src/tools/clippy/clippy_lints/src/utils/internal_lints/lint_without_lint_pass.rs b/src/tools/clippy/clippy_lints/src/utils/internal_lints/lint_without_lint_pass.rs
new file mode 100644
index 000000000000..0dac64376b06
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/utils/internal_lints/lint_without_lint_pass.rs
@@ -0,0 +1,342 @@
+use crate::utils::internal_lints::metadata_collector::is_deprecated_lint;
+use clippy_utils::diagnostics::{span_lint, span_lint_and_help};
+use clippy_utils::macros::root_macro_call_first_node;
+use clippy_utils::{is_lint_allowed, match_def_path, paths};
+use if_chain::if_chain;
+use rustc_ast as ast;
+use rustc_ast::ast::LitKind;
+use rustc_data_structures::fx::{FxHashMap, FxHashSet};
+use rustc_hir as hir;
+use rustc_hir::def::{DefKind, Res};
+use rustc_hir::hir_id::CRATE_HIR_ID;
+use rustc_hir::intravisit::Visitor;
+use rustc_hir::{ExprKind, HirId, Item, MutTy, Mutability, Path, TyKind};
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_middle::hir::nested_filter;
+use rustc_semver::RustcVersion;
+use rustc_session::{declare_tool_lint, impl_lint_pass};
+use rustc_span::source_map::Spanned;
+use rustc_span::symbol::Symbol;
+use rustc_span::{sym, Span};
+
+declare_clippy_lint! {
+    /// ### What it does
+    /// Ensures every lint is associated to a `LintPass`.
+    ///
+    /// ### Why is this bad?
+    /// The compiler only knows lints via a `LintPass`. Without
+    /// putting a lint to a `LintPass::get_lints()`'s return, the compiler will not
+    /// know the name of the lint.
+    ///
+    /// ### Known problems
+    /// Only checks for lints associated using the
+    /// `declare_lint_pass!`, `impl_lint_pass!`, and `lint_array!` macros.
+    ///
+    /// ### Example
+    /// ```rust,ignore
+    /// declare_lint! { pub LINT_1, ... }
+    /// declare_lint! { pub LINT_2, ... }
+    /// declare_lint! { pub FORGOTTEN_LINT, ... }
+    /// // ...
+    /// declare_lint_pass!(Pass => [LINT_1, LINT_2]);
+    /// // missing FORGOTTEN_LINT
+    /// ```
+    pub LINT_WITHOUT_LINT_PASS,
+    internal,
+    "declaring a lint without associating it in a LintPass"
+}
+
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks for cases of an auto-generated lint without an updated description,
+    /// i.e. `default lint description`.
+    ///
+    /// ### Why is this bad?
+    /// Indicates that the lint is not finished.
+    ///
+    /// ### Example
+    /// ```rust,ignore
+    /// declare_lint! { pub COOL_LINT, nursery, "default lint description" }
+    /// ```
+    ///
+    /// Use instead:
+    /// ```rust,ignore
+    /// declare_lint! { pub COOL_LINT, nursery, "a great new lint" }
+    /// ```
+    pub DEFAULT_LINT,
+    internal,
+    "found 'default lint description' in a lint declaration"
+}
+
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks for invalid `clippy::version` attributes.
+    ///
+    /// Valid values are:
+    /// * "pre 1.29.0"
+    /// * any valid semantic version
+    pub INVALID_CLIPPY_VERSION_ATTRIBUTE,
+    internal,
+    "found an invalid `clippy::version` attribute"
+}
+
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks for declared clippy lints without the `clippy::version` attribute.
+    ///
+    pub MISSING_CLIPPY_VERSION_ATTRIBUTE,
+    internal,
+    "found clippy lint without `clippy::version` attribute"
+}
+
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks for cases of an auto-generated deprecated lint without an updated reason,
+    /// i.e. `"default deprecation note"`.
+    ///
+    /// ### Why is this bad?
+    /// Indicates that the documentation is incomplete.
+    ///
+    /// ### Example
+    /// ```rust,ignore
+    /// declare_deprecated_lint! {
+    ///     /// ### What it does
+    ///     /// Nothing. This lint has been deprecated.
+    ///     ///
+    ///     /// ### Deprecation reason
+    ///     /// TODO
+    ///     #[clippy::version = "1.63.0"]
+    ///     pub COOL_LINT,
+    ///     "default deprecation note"
+    /// }
+    /// ```
+    ///
+    /// Use instead:
+    /// ```rust,ignore
+    /// declare_deprecated_lint! {
+    ///     /// ### What it does
+    ///     /// Nothing. This lint has been deprecated.
+    ///     ///
+    ///     /// ### Deprecation reason
+    ///     /// This lint has been replaced by `cooler_lint`
+    ///     #[clippy::version = "1.63.0"]
+    ///     pub COOL_LINT,
+    ///     "this lint has been replaced by `cooler_lint`"
+    /// }
+    /// ```
+    pub DEFAULT_DEPRECATION_REASON,
+    internal,
+    "found 'default deprecation note' in a deprecated lint declaration"
+}
+
+#[derive(Clone, Debug, Default)]
+pub struct LintWithoutLintPass {
+    declared_lints: FxHashMap<Symbol, Span>,
+    registered_lints: FxHashSet<Symbol>,
+}
+
+impl_lint_pass!(LintWithoutLintPass => [DEFAULT_LINT, LINT_WITHOUT_LINT_PASS, INVALID_CLIPPY_VERSION_ATTRIBUTE, MISSING_CLIPPY_VERSION_ATTRIBUTE, DEFAULT_DEPRECATION_REASON]);
+
+impl<'tcx> LateLintPass<'tcx> for LintWithoutLintPass {
+    fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'_>) {
+        if is_lint_allowed(cx, DEFAULT_LINT, item.hir_id())
+            || is_lint_allowed(cx, DEFAULT_DEPRECATION_REASON, item.hir_id())
+        {
+            return;
+        }
+
+        if let hir::ItemKind::Static(ty, Mutability::Not, body_id) = item.kind {
+            let is_lint_ref_ty = is_lint_ref_type(cx, ty);
+            if is_deprecated_lint(cx, ty) || is_lint_ref_ty {
+                check_invalid_clippy_version_attribute(cx, item);
+
+                let expr = &cx.tcx.hir().body(body_id).value;
+                let fields;
+                if is_lint_ref_ty {
+                    if let ExprKind::AddrOf(_, _, inner_exp) = expr.kind
+                        && let ExprKind::Struct(_, struct_fields, _) = inner_exp.kind {
+                            fields = struct_fields;
+                    } else {
+                        return;
+                    }
+                } else if let ExprKind::Struct(_, struct_fields, _) = expr.kind {
+                    fields = struct_fields;
+                } else {
+                    return;
+                }
+
+                let field = fields
+                    .iter()
+                    .find(|f| f.ident.as_str() == "desc")
+                    .expect("lints must have a description field");
+
+                if let ExprKind::Lit(Spanned {
+                    node: LitKind::Str(ref sym, _),
+                    ..
+                }) = field.expr.kind
+                {
+                    let sym_str = sym.as_str();
+                    if is_lint_ref_ty {
+                        if sym_str == "default lint description" {
+                            span_lint(
+                                cx,
+                                DEFAULT_LINT,
+                                item.span,
+                                &format!("the lint `{}` has the default lint description", item.ident.name),
+                            );
+                        }
+
+                        self.declared_lints.insert(item.ident.name, item.span);
+                    } else if sym_str == "default deprecation note" {
+                        span_lint(
+                            cx,
+                            DEFAULT_DEPRECATION_REASON,
+                            item.span,
+                            &format!("the lint `{}` has the default deprecation reason", item.ident.name),
+                        );
+                    }
+                }
+            }
+        } else if let Some(macro_call) = root_macro_call_first_node(cx, item) {
+            if !matches!(
+                cx.tcx.item_name(macro_call.def_id).as_str(),
+                "impl_lint_pass" | "declare_lint_pass"
+            ) {
+                return;
+            }
+            if let hir::ItemKind::Impl(hir::Impl {
+                of_trait: None,
+                items: impl_item_refs,
+                ..
+            }) = item.kind
+            {
+                let mut collector = LintCollector {
+                    output: &mut self.registered_lints,
+                    cx,
+                };
+                let body_id = cx.tcx.hir().body_owned_by(
+                    cx.tcx.hir().local_def_id(
+                        impl_item_refs
+                            .iter()
+                            .find(|iiref| iiref.ident.as_str() == "get_lints")
+                            .expect("LintPass needs to implement get_lints")
+                            .id
+                            .hir_id(),
+                    ),
+                );
+                collector.visit_expr(cx.tcx.hir().body(body_id).value);
+            }
+        }
+    }
+
+    fn check_crate_post(&mut self, cx: &LateContext<'tcx>) {
+        if is_lint_allowed(cx, LINT_WITHOUT_LINT_PASS, CRATE_HIR_ID) {
+            return;
+        }
+
+        for (lint_name, &lint_span) in &self.declared_lints {
+            // When using the `declare_tool_lint!` macro, the original `lint_span`'s
+            // file points to "<rustc macros>".
+            // `compiletest-rs` thinks that's an error in a different file and
+            // just ignores it. This causes the test in compile-fail/lint_pass
+            // not able to capture the error.
+            // Therefore, we need to climb the macro expansion tree and find the
+            // actual span that invoked `declare_tool_lint!`:
+            let lint_span = lint_span.ctxt().outer_expn_data().call_site;
+
+            if !self.registered_lints.contains(lint_name) {
+                span_lint(
+                    cx,
+                    LINT_WITHOUT_LINT_PASS,
+                    lint_span,
+                    &format!("the lint `{lint_name}` is not added to any `LintPass`"),
+                );
+            }
+        }
+    }
+}
+
+pub(super) fn is_lint_ref_type<'tcx>(cx: &LateContext<'tcx>, ty: &hir::Ty<'_>) -> bool {
+    if let TyKind::Rptr(
+        _,
+        MutTy {
+            ty: inner,
+            mutbl: Mutability::Not,
+        },
+    ) = ty.kind
+    {
+        if let TyKind::Path(ref path) = inner.kind {
+            if let Res::Def(DefKind::Struct, def_id) = cx.qpath_res(path, inner.hir_id) {
+                return match_def_path(cx, def_id, &paths::LINT);
+            }
+        }
+    }
+
+    false
+}
+
+fn check_invalid_clippy_version_attribute(cx: &LateContext<'_>, item: &'_ Item<'_>) {
+    if let Some(value) = extract_clippy_version_value(cx, item) {
+        // The `sym!` macro doesn't work as it only expects a single token.
+        // It's better to keep it this way and have a direct `Symbol::intern` call here.
+        if value == Symbol::intern("pre 1.29.0") {
+            return;
+        }
+
+        if RustcVersion::parse(value.as_str()).is_err() {
+            span_lint_and_help(
+                cx,
+                INVALID_CLIPPY_VERSION_ATTRIBUTE,
+                item.span,
+                "this item has an invalid `clippy::version` attribute",
+                None,
+                "please use a valid semantic version, see `doc/adding_lints.md`",
+            );
+        }
+    } else {
+        span_lint_and_help(
+            cx,
+            MISSING_CLIPPY_VERSION_ATTRIBUTE,
+            item.span,
+            "this lint is missing the `clippy::version` attribute or version value",
+            None,
+            "please use a `clippy::version` attribute, see `doc/adding_lints.md`",
+        );
+    }
+}
+
+/// This function extracts the version value of a `clippy::version` attribute if the given value has
+/// one
+pub(super) fn extract_clippy_version_value(cx: &LateContext<'_>, item: &'_ Item<'_>) -> Option<Symbol> {
+    let attrs = cx.tcx.hir().attrs(item.hir_id());
+    attrs.iter().find_map(|attr| {
+        if_chain! {
+            // Identify attribute
+            if let ast::AttrKind::Normal(ref attr_kind) = &attr.kind;
+            if let [tool_name, attr_name] = &attr_kind.item.path.segments[..];
+            if tool_name.ident.name == sym::clippy;
+            if attr_name.ident.name == sym::version;
+            if let Some(version) = attr.value_str();
+            then { Some(version) } else { None }
+        }
+    })
+}
+
+struct LintCollector<'a, 'tcx> {
+    output: &'a mut FxHashSet<Symbol>,
+    cx: &'a LateContext<'tcx>,
+}
+
+impl<'a, 'tcx> Visitor<'tcx> for LintCollector<'a, 'tcx> {
+    type NestedFilter = nested_filter::All;
+
+    fn visit_path(&mut self, path: &'tcx Path<'_>, _: HirId) {
+        if path.segments.len() == 1 {
+            self.output.insert(path.segments[0].ident.name);
+        }
+    }
+
+    fn nested_visit_map(&mut self) -> Self::Map {
+        self.cx.tcx.hir()
+    }
+}
diff --git a/src/tools/clippy/clippy_lints/src/utils/internal_lints/metadata_collector.rs b/src/tools/clippy/clippy_lints/src/utils/internal_lints/metadata_collector.rs
index c84191bb0103..d06a616e4b30 100644
--- a/src/tools/clippy/clippy_lints/src/utils/internal_lints/metadata_collector.rs
+++ b/src/tools/clippy/clippy_lints/src/utils/internal_lints/metadata_collector.rs
@@ -8,7 +8,7 @@
 //! a simple mistake)
 
 use crate::renamed_lints::RENAMED_LINTS;
-use crate::utils::internal_lints::{extract_clippy_version_value, is_lint_ref_type};
+use crate::utils::internal_lints::lint_without_lint_pass::{extract_clippy_version_value, is_lint_ref_type};
 
 use clippy_utils::diagnostics::span_lint;
 use clippy_utils::ty::{match_type, walk_ptrs_ty_depth};
@@ -532,7 +532,11 @@ fn parse_config_field_doc(doc_comment: &str) -> Option<(Vec<String>, String)> {
 
             // Extract lints
             doc_comment.make_ascii_lowercase();
-            let lints: Vec<String> = doc_comment.split_off(DOC_START.len()).split(", ").map(str::to_string).collect();
+            let lints: Vec<String> = doc_comment
+                .split_off(DOC_START.len())
+                .split(", ")
+                .map(str::to_string)
+                .collect();
 
             // Format documentation correctly
             // split off leading `.` from lint name list and indent for correct formatting
diff --git a/src/tools/clippy/clippy_lints/src/utils/internal_lints/msrv_attr_impl.rs b/src/tools/clippy/clippy_lints/src/utils/internal_lints/msrv_attr_impl.rs
new file mode 100644
index 000000000000..1e994e3f2b17
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/utils/internal_lints/msrv_attr_impl.rs
@@ -0,0 +1,63 @@
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::source::snippet;
+use clippy_utils::ty::match_type;
+use clippy_utils::{match_def_path, paths};
+use if_chain::if_chain;
+use rustc_errors::Applicability;
+use rustc_hir as hir;
+use rustc_hir_analysis::hir_ty_to_ty;
+use rustc_lint::{LateContext, LateLintPass, LintContext};
+use rustc_middle::ty::{self, subst::GenericArgKind};
+use rustc_session::{declare_lint_pass, declare_tool_lint};
+
+declare_clippy_lint! {
+    /// ### What it does
+    /// Check that the `extract_msrv_attr!` macro is used, when a lint has a MSRV.
+    ///
+    pub MISSING_MSRV_ATTR_IMPL,
+    internal,
+    "checking if all necessary steps were taken when adding a MSRV to a lint"
+}
+
+declare_lint_pass!(MsrvAttrImpl => [MISSING_MSRV_ATTR_IMPL]);
+
+impl LateLintPass<'_> for MsrvAttrImpl {
+    fn check_item(&mut self, cx: &LateContext<'_>, item: &hir::Item<'_>) {
+        if_chain! {
+            if let hir::ItemKind::Impl(hir::Impl {
+                of_trait: Some(lint_pass_trait_ref),
+                self_ty,
+                items,
+                ..
+            }) = &item.kind;
+            if let Some(lint_pass_trait_def_id) = lint_pass_trait_ref.trait_def_id();
+            let is_late_pass = match_def_path(cx, lint_pass_trait_def_id, &paths::LATE_LINT_PASS);
+            if is_late_pass || match_def_path(cx, lint_pass_trait_def_id, &paths::EARLY_LINT_PASS);
+            let self_ty = hir_ty_to_ty(cx.tcx, self_ty);
+            if let ty::Adt(self_ty_def, _) = self_ty.kind();
+            if self_ty_def.is_struct();
+            if self_ty_def.all_fields().any(|f| {
+                cx.tcx
+                    .type_of(f.did)
+                    .walk()
+                    .filter(|t| matches!(t.unpack(), GenericArgKind::Type(_)))
+                    .any(|t| match_type(cx, t.expect_ty(), &paths::RUSTC_VERSION))
+            });
+            if !items.iter().any(|item| item.ident.name == sym!(enter_lint_attrs));
+            then {
+                let context = if is_late_pass { "LateContext" } else { "EarlyContext" };
+                let lint_pass = if is_late_pass { "LateLintPass" } else { "EarlyLintPass" };
+                let span = cx.sess().source_map().span_through_char(item.span, '{');
+                span_lint_and_sugg(
+                    cx,
+                    MISSING_MSRV_ATTR_IMPL,
+                    span,
+                    &format!("`extract_msrv_attr!` macro missing from `{lint_pass}` implementation"),
+                    &format!("add `extract_msrv_attr!({context})` to the `{lint_pass}` implementation"),
+                    format!("{}\n    extract_msrv_attr!({context});", snippet(cx, span, "..")),
+                    Applicability::MachineApplicable,
+                );
+            }
+        }
+    }
+}
diff --git a/src/tools/clippy/clippy_lints/src/utils/internal_lints/outer_expn_data_pass.rs b/src/tools/clippy/clippy_lints/src/utils/internal_lints/outer_expn_data_pass.rs
new file mode 100644
index 000000000000..2b13fad80665
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/utils/internal_lints/outer_expn_data_pass.rs
@@ -0,0 +1,62 @@
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::ty::match_type;
+use clippy_utils::{is_lint_allowed, method_calls, paths};
+use if_chain::if_chain;
+use rustc_errors::Applicability;
+use rustc_hir as hir;
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_session::{declare_lint_pass, declare_tool_lint};
+use rustc_span::symbol::Symbol;
+
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks for calls to `cx.outer().expn_data()` and suggests to use
+    /// the `cx.outer_expn_data()`
+    ///
+    /// ### Why is this bad?
+    /// `cx.outer_expn_data()` is faster and more concise.
+    ///
+    /// ### Example
+    /// ```rust,ignore
+    /// expr.span.ctxt().outer().expn_data()
+    /// ```
+    ///
+    /// Use instead:
+    /// ```rust,ignore
+    /// expr.span.ctxt().outer_expn_data()
+    /// ```
+    pub OUTER_EXPN_EXPN_DATA,
+    internal,
+    "using `cx.outer_expn().expn_data()` instead of `cx.outer_expn_data()`"
+}
+
+declare_lint_pass!(OuterExpnDataPass => [OUTER_EXPN_EXPN_DATA]);
+
+impl<'tcx> LateLintPass<'tcx> for OuterExpnDataPass {
+    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>) {
+        if is_lint_allowed(cx, OUTER_EXPN_EXPN_DATA, expr.hir_id) {
+            return;
+        }
+
+        let (method_names, arg_lists, spans) = method_calls(expr, 2);
+        let method_names: Vec<&str> = method_names.iter().map(Symbol::as_str).collect();
+        if_chain! {
+            if let ["expn_data", "outer_expn"] = method_names.as_slice();
+            let (self_arg, args) = arg_lists[1];
+            if args.is_empty();
+            let self_ty = cx.typeck_results().expr_ty(self_arg).peel_refs();
+            if match_type(cx, self_ty, &paths::SYNTAX_CONTEXT);
+            then {
+                span_lint_and_sugg(
+                    cx,
+                    OUTER_EXPN_EXPN_DATA,
+                    spans[1].with_hi(expr.span.hi()),
+                    "usage of `outer_expn().expn_data()`",
+                    "try",
+                    "outer_expn_data()".to_string(),
+                    Applicability::MachineApplicable,
+                );
+            }
+        }
+    }
+}
diff --git a/src/tools/clippy/clippy_lints/src/utils/internal_lints/produce_ice.rs b/src/tools/clippy/clippy_lints/src/utils/internal_lints/produce_ice.rs
new file mode 100644
index 000000000000..5899b94e16ba
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/utils/internal_lints/produce_ice.rs
@@ -0,0 +1,37 @@
+use rustc_ast::ast::NodeId;
+use rustc_ast::visit::FnKind;
+use rustc_lint::{EarlyContext, EarlyLintPass};
+use rustc_session::{declare_lint_pass, declare_tool_lint};
+use rustc_span::Span;
+
+declare_clippy_lint! {
+    /// ### What it does
+    /// Not an actual lint. This lint is only meant for testing our customized internal compiler
+    /// error message by calling `panic`.
+    ///
+    /// ### Why is this bad?
+    /// ICE in large quantities can damage your teeth
+    ///
+    /// ### Example
+    /// ```rust,ignore
+    /// 🍦🍦🍦🍦🍦
+    /// ```
+    pub PRODUCE_ICE,
+    internal,
+    "this message should not appear anywhere as we ICE before and don't emit the lint"
+}
+
+declare_lint_pass!(ProduceIce => [PRODUCE_ICE]);
+
+impl EarlyLintPass for ProduceIce {
+    fn check_fn(&mut self, _: &EarlyContext<'_>, fn_kind: FnKind<'_>, _: Span, _: NodeId) {
+        assert!(!is_trigger_fn(fn_kind), "Would you like some help with that?");
+    }
+}
+
+fn is_trigger_fn(fn_kind: FnKind<'_>) -> bool {
+    match fn_kind {
+        FnKind::Fn(_, ident, ..) => ident.name.as_str() == "it_looks_like_you_are_trying_to_kill_clippy",
+        FnKind::Closure(..) => false,
+    }
+}
diff --git a/src/tools/clippy/clippy_lints/src/utils/internal_lints/unnecessary_def_path.rs b/src/tools/clippy/clippy_lints/src/utils/internal_lints/unnecessary_def_path.rs
new file mode 100644
index 000000000000..2a028c8141fc
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/utils/internal_lints/unnecessary_def_path.rs
@@ -0,0 +1,343 @@
+use clippy_utils::diagnostics::{span_lint_and_help, span_lint_and_then};
+use clippy_utils::source::snippet_with_applicability;
+use clippy_utils::{def_path_res, is_lint_allowed, match_any_def_paths, peel_hir_expr_refs};
+use if_chain::if_chain;
+use rustc_ast::ast::LitKind;
+use rustc_data_structures::fx::FxHashSet;
+use rustc_errors::Applicability;
+use rustc_hir as hir;
+use rustc_hir::def::{DefKind, Namespace, Res};
+use rustc_hir::def_id::DefId;
+use rustc_hir::{Expr, ExprKind, Local, Mutability, Node};
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_middle::mir::interpret::{Allocation, ConstValue, GlobalAlloc};
+use rustc_middle::ty::{self, AssocKind, DefIdTree, Ty};
+use rustc_session::{declare_tool_lint, impl_lint_pass};
+use rustc_span::symbol::{Ident, Symbol};
+use rustc_span::Span;
+
+use std::str;
+
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks for usages of def paths when a diagnostic item or a `LangItem` could be used.
+    ///
+    /// ### Why is this bad?
+    /// The path for an item is subject to change and is less efficient to look up than a
+    /// diagnostic item or a `LangItem`.
+    ///
+    /// ### Example
+    /// ```rust,ignore
+    /// utils::match_type(cx, ty, &paths::VEC)
+    /// ```
+    ///
+    /// Use instead:
+    /// ```rust,ignore
+    /// utils::is_type_diagnostic_item(cx, ty, sym::Vec)
+    /// ```
+    pub UNNECESSARY_DEF_PATH,
+    internal,
+    "using a def path when a diagnostic item or a `LangItem` is available"
+}
+
+impl_lint_pass!(UnnecessaryDefPath => [UNNECESSARY_DEF_PATH]);
+
+#[derive(Default)]
+pub struct UnnecessaryDefPath {
+    array_def_ids: FxHashSet<(DefId, Span)>,
+    linted_def_ids: FxHashSet<DefId>,
+}
+
+impl<'tcx> LateLintPass<'tcx> for UnnecessaryDefPath {
+    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>) {
+        if is_lint_allowed(cx, UNNECESSARY_DEF_PATH, expr.hir_id) {
+            return;
+        }
+
+        match expr.kind {
+            ExprKind::Call(func, args) => self.check_call(cx, func, args, expr.span),
+            ExprKind::Array(elements) => self.check_array(cx, elements, expr.span),
+            _ => {},
+        }
+    }
+
+    fn check_crate_post(&mut self, cx: &LateContext<'tcx>) {
+        for &(def_id, span) in &self.array_def_ids {
+            if self.linted_def_ids.contains(&def_id) {
+                continue;
+            }
+
+            let (msg, sugg) = if let Some(sym) = cx.tcx.get_diagnostic_name(def_id) {
+                ("diagnostic item", format!("sym::{sym}"))
+            } else if let Some(sym) = get_lang_item_name(cx, def_id) {
+                ("language item", format!("LangItem::{sym}"))
+            } else {
+                continue;
+            };
+
+            span_lint_and_help(
+                cx,
+                UNNECESSARY_DEF_PATH,
+                span,
+                &format!("hardcoded path to a {msg}"),
+                None,
+                &format!("convert all references to use `{sugg}`"),
+            );
+        }
+    }
+}
+
+impl UnnecessaryDefPath {
+    #[allow(clippy::too_many_lines)]
+    fn check_call(&mut self, cx: &LateContext<'_>, func: &Expr<'_>, args: &[Expr<'_>], span: Span) {
+        enum Item {
+            LangItem(Symbol),
+            DiagnosticItem(Symbol),
+        }
+        static PATHS: &[&[&str]] = &[
+            &["clippy_utils", "match_def_path"],
+            &["clippy_utils", "match_trait_method"],
+            &["clippy_utils", "ty", "match_type"],
+            &["clippy_utils", "is_expr_path_def_path"],
+        ];
+
+        if_chain! {
+            if let [cx_arg, def_arg, args @ ..] = args;
+            if let ExprKind::Path(path) = &func.kind;
+            if let Some(id) = cx.qpath_res(path, func.hir_id).opt_def_id();
+            if let Some(which_path) = match_any_def_paths(cx, id, PATHS);
+            let item_arg = if which_path == 4 { &args[1] } else { &args[0] };
+            // Extract the path to the matched type
+            if let Some(segments) = path_to_matched_type(cx, item_arg);
+            let segments: Vec<&str> = segments.iter().map(|sym| &**sym).collect();
+            if let Some(def_id) = inherent_def_path_res(cx, &segments[..]);
+            then {
+                // Check if the target item is a diagnostic item or LangItem.
+                #[rustfmt::skip]
+                let (msg, item) = if let Some(item_name)
+                    = cx.tcx.diagnostic_items(def_id.krate).id_to_name.get(&def_id)
+                {
+                    (
+                        "use of a def path to a diagnostic item",
+                        Item::DiagnosticItem(*item_name),
+                    )
+                } else if let Some(item_name) = get_lang_item_name(cx, def_id) {
+                    (
+                        "use of a def path to a `LangItem`",
+                        Item::LangItem(item_name),
+                    )
+                } else {
+                    return;
+                };
+
+                let has_ctor = match cx.tcx.def_kind(def_id) {
+                    DefKind::Struct => {
+                        let variant = cx.tcx.adt_def(def_id).non_enum_variant();
+                        variant.ctor_def_id.is_some() && variant.fields.iter().all(|f| f.vis.is_public())
+                    },
+                    DefKind::Variant => {
+                        let variant = cx.tcx.adt_def(cx.tcx.parent(def_id)).variant_with_id(def_id);
+                        variant.ctor_def_id.is_some() && variant.fields.iter().all(|f| f.vis.is_public())
+                    },
+                    _ => false,
+                };
+
+                let mut app = Applicability::MachineApplicable;
+                let cx_snip = snippet_with_applicability(cx, cx_arg.span, "..", &mut app);
+                let def_snip = snippet_with_applicability(cx, def_arg.span, "..", &mut app);
+                let (sugg, with_note) = match (which_path, item) {
+                    // match_def_path
+                    (0, Item::DiagnosticItem(item)) => (
+                        format!("{cx_snip}.tcx.is_diagnostic_item(sym::{item}, {def_snip})"),
+                        has_ctor,
+                    ),
+                    (0, Item::LangItem(item)) => (
+                        format!("{cx_snip}.tcx.lang_items().get(LangItem::{item}) == Some({def_snip})"),
+                        has_ctor,
+                    ),
+                    // match_trait_method
+                    (1, Item::DiagnosticItem(item)) => {
+                        (format!("is_trait_method({cx_snip}, {def_snip}, sym::{item})"), false)
+                    },
+                    // match_type
+                    (2, Item::DiagnosticItem(item)) => (
+                        format!("is_type_diagnostic_item({cx_snip}, {def_snip}, sym::{item})"),
+                        false,
+                    ),
+                    (2, Item::LangItem(item)) => (
+                        format!("is_type_lang_item({cx_snip}, {def_snip}, LangItem::{item})"),
+                        false,
+                    ),
+                    // is_expr_path_def_path
+                    (3, Item::DiagnosticItem(item)) if has_ctor => (
+                        format!("is_res_diag_ctor({cx_snip}, path_res({cx_snip}, {def_snip}), sym::{item})",),
+                        false,
+                    ),
+                    (3, Item::LangItem(item)) if has_ctor => (
+                        format!("is_res_lang_ctor({cx_snip}, path_res({cx_snip}, {def_snip}), LangItem::{item})",),
+                        false,
+                    ),
+                    (3, Item::DiagnosticItem(item)) => (
+                        format!("is_path_diagnostic_item({cx_snip}, {def_snip}, sym::{item})"),
+                        false,
+                    ),
+                    (3, Item::LangItem(item)) => (
+                        format!(
+                            "path_res({cx_snip}, {def_snip}).opt_def_id()\
+                                .map_or(false, |id| {cx_snip}.tcx.lang_items().get(LangItem::{item}) == Some(id))",
+                        ),
+                        false,
+                    ),
+                    _ => return,
+                };
+
+                span_lint_and_then(cx, UNNECESSARY_DEF_PATH, span, msg, |diag| {
+                    diag.span_suggestion(span, "try", sugg, app);
+                    if with_note {
+                        diag.help(
+                            "if this `DefId` came from a constructor expression or pattern then the \
+                                    parent `DefId` should be used instead",
+                        );
+                    }
+                });
+
+                self.linted_def_ids.insert(def_id);
+            }
+        }
+    }
+
+    fn check_array(&mut self, cx: &LateContext<'_>, elements: &[Expr<'_>], span: Span) {
+        let Some(path) = path_from_array(elements) else { return };
+
+        if let Some(def_id) = inherent_def_path_res(cx, &path.iter().map(AsRef::as_ref).collect::<Vec<_>>()) {
+            self.array_def_ids.insert((def_id, span));
+        }
+    }
+}
+
+fn path_to_matched_type(cx: &LateContext<'_>, expr: &hir::Expr<'_>) -> Option<Vec<String>> {
+    match peel_hir_expr_refs(expr).0.kind {
+        ExprKind::Path(ref qpath) => match cx.qpath_res(qpath, expr.hir_id) {
+            Res::Local(hir_id) => {
+                let parent_id = cx.tcx.hir().get_parent_node(hir_id);
+                if let Some(Node::Local(Local { init: Some(init), .. })) = cx.tcx.hir().find(parent_id) {
+                    path_to_matched_type(cx, init)
+                } else {
+                    None
+                }
+            },
+            Res::Def(DefKind::Static(_), def_id) => read_mir_alloc_def_path(
+                cx,
+                cx.tcx.eval_static_initializer(def_id).ok()?.inner(),
+                cx.tcx.type_of(def_id),
+            ),
+            Res::Def(DefKind::Const, def_id) => match cx.tcx.const_eval_poly(def_id).ok()? {
+                ConstValue::ByRef { alloc, offset } if offset.bytes() == 0 => {
+                    read_mir_alloc_def_path(cx, alloc.inner(), cx.tcx.type_of(def_id))
+                },
+                _ => None,
+            },
+            _ => None,
+        },
+        ExprKind::Array(exprs) => path_from_array(exprs),
+        _ => None,
+    }
+}
+
+fn read_mir_alloc_def_path<'tcx>(cx: &LateContext<'tcx>, alloc: &'tcx Allocation, ty: Ty<'_>) -> Option<Vec<String>> {
+    let (alloc, ty) = if let ty::Ref(_, ty, Mutability::Not) = *ty.kind() {
+        let &alloc = alloc.provenance().values().next()?;
+        if let GlobalAlloc::Memory(alloc) = cx.tcx.global_alloc(alloc) {
+            (alloc.inner(), ty)
+        } else {
+            return None;
+        }
+    } else {
+        (alloc, ty)
+    };
+
+    if let ty::Array(ty, _) | ty::Slice(ty) = *ty.kind()
+        && let ty::Ref(_, ty, Mutability::Not) = *ty.kind()
+        && ty.is_str()
+    {
+        alloc
+            .provenance()
+            .values()
+            .map(|&alloc| {
+                if let GlobalAlloc::Memory(alloc) = cx.tcx.global_alloc(alloc) {
+                    let alloc = alloc.inner();
+                    str::from_utf8(alloc.inspect_with_uninit_and_ptr_outside_interpreter(0..alloc.len()))
+                        .ok().map(ToOwned::to_owned)
+                } else {
+                    None
+                }
+            })
+            .collect()
+    } else {
+        None
+    }
+}
+
+fn path_from_array(exprs: &[Expr<'_>]) -> Option<Vec<String>> {
+    exprs
+        .iter()
+        .map(|expr| {
+            if let ExprKind::Lit(lit) = &expr.kind {
+                if let LitKind::Str(sym, _) = lit.node {
+                    return Some((*sym.as_str()).to_owned());
+                }
+            }
+
+            None
+        })
+        .collect()
+}
+
+// def_path_res will match field names before anything else, but for this we want to match
+// inherent functions first.
+fn inherent_def_path_res(cx: &LateContext<'_>, segments: &[&str]) -> Option<DefId> {
+    def_path_res(cx, segments, None).opt_def_id().map(|def_id| {
+        if cx.tcx.def_kind(def_id) == DefKind::Field {
+            let method_name = *segments.last().unwrap();
+            cx.tcx
+                .def_key(def_id)
+                .parent
+                .and_then(|parent_idx| {
+                    cx.tcx
+                        .inherent_impls(DefId {
+                            index: parent_idx,
+                            krate: def_id.krate,
+                        })
+                        .iter()
+                        .find_map(|impl_id| {
+                            cx.tcx.associated_items(*impl_id).find_by_name_and_kind(
+                                cx.tcx,
+                                Ident::from_str(method_name),
+                                AssocKind::Fn,
+                                *impl_id,
+                            )
+                        })
+                })
+                .map_or(def_id, |item| item.def_id)
+        } else {
+            def_id
+        }
+    })
+}
+
+fn get_lang_item_name(cx: &LateContext<'_>, def_id: DefId) -> Option<Symbol> {
+    if let Some(lang_item) = cx.tcx.lang_items().items().iter().position(|id| *id == Some(def_id)) {
+        let lang_items = def_path_res(cx, &["rustc_hir", "lang_items", "LangItem"], Some(Namespace::TypeNS)).def_id();
+        let item_name = cx
+            .tcx
+            .adt_def(lang_items)
+            .variants()
+            .iter()
+            .nth(lang_item)
+            .unwrap()
+            .name;
+        Some(item_name)
+    } else {
+        None
+    }
+}
diff --git a/src/tools/clippy/clippy_lints/src/wildcard_imports.rs b/src/tools/clippy/clippy_lints/src/wildcard_imports.rs
index 301eed9a1fbf..be98344470b9 100644
--- a/src/tools/clippy/clippy_lints/src/wildcard_imports.rs
+++ b/src/tools/clippy/clippy_lints/src/wildcard_imports.rs
@@ -120,14 +120,14 @@ impl LateLintPass<'_> for WildcardImports {
         if is_test_module_or_function(cx.tcx, item) {
             self.test_modules_deep = self.test_modules_deep.saturating_add(1);
         }
-        let module = cx.tcx.parent_module_from_def_id(item.def_id.def_id);
-        if cx.tcx.visibility(item.def_id.def_id) != ty::Visibility::Restricted(module.to_def_id()) {
+        let module = cx.tcx.parent_module_from_def_id(item.owner_id.def_id);
+        if cx.tcx.visibility(item.owner_id.def_id) != ty::Visibility::Restricted(module.to_def_id()) {
             return;
         }
         if_chain! {
             if let ItemKind::Use(use_path, UseKind::Glob) = &item.kind;
             if self.warn_on_all || !self.check_exceptions(item, use_path.segments);
-            let used_imports = cx.tcx.names_imported_by_glob_use(item.def_id.def_id);
+            let used_imports = cx.tcx.names_imported_by_glob_use(item.owner_id.def_id);
             if !used_imports.is_empty(); // Already handled by `unused_imports`
             then {
                 let mut applicability = Applicability::MachineApplicable;
diff --git a/src/tools/clippy/clippy_utils/src/attrs.rs b/src/tools/clippy/clippy_utils/src/attrs.rs
index d9b22664fd25..cd8575c90e86 100644
--- a/src/tools/clippy/clippy_utils/src/attrs.rs
+++ b/src/tools/clippy/clippy_utils/src/attrs.rs
@@ -136,7 +136,7 @@ pub fn get_unique_inner_attr(sess: &Session, attrs: &[ast::Attribute], name: &'s
                     .emit();
             },
             ast::AttrStyle::Outer => {
-                sess.span_err(attr.span, &format!("`{name}` cannot be an outer attribute"));
+                sess.span_err(attr.span, format!("`{name}` cannot be an outer attribute"));
             },
         }
     }
diff --git a/src/tools/clippy/clippy_utils/src/consts.rs b/src/tools/clippy/clippy_utils/src/consts.rs
index fa6766f7cfe1..07e4ef6a2fef 100644
--- a/src/tools/clippy/clippy_utils/src/consts.rs
+++ b/src/tools/clippy/clippy_utils/src/consts.rs
@@ -136,17 +136,49 @@ impl Constant {
             (&Self::F64(l), &Self::F64(r)) => l.partial_cmp(&r),
             (&Self::F32(l), &Self::F32(r)) => l.partial_cmp(&r),
             (&Self::Bool(ref l), &Self::Bool(ref r)) => Some(l.cmp(r)),
-            (&Self::Tuple(ref l), &Self::Tuple(ref r)) | (&Self::Vec(ref l), &Self::Vec(ref r)) => iter::zip(l, r)
-                .map(|(li, ri)| Self::partial_cmp(tcx, cmp_type, li, ri))
-                .find(|r| r.map_or(true, |o| o != Ordering::Equal))
-                .unwrap_or_else(|| Some(l.len().cmp(&r.len()))),
+            (&Self::Tuple(ref l), &Self::Tuple(ref r)) if l.len() == r.len() => match *cmp_type.kind() {
+                ty::Tuple(tys) if tys.len() == l.len() => l
+                    .iter()
+                    .zip(r)
+                    .zip(tys)
+                    .map(|((li, ri), cmp_type)| Self::partial_cmp(tcx, cmp_type, li, ri))
+                    .find(|r| r.map_or(true, |o| o != Ordering::Equal))
+                    .unwrap_or_else(|| Some(l.len().cmp(&r.len()))),
+                _ => None,
+            },
+            (&Self::Vec(ref l), &Self::Vec(ref r)) => {
+                let cmp_type = match *cmp_type.kind() {
+                    ty::Array(ty, _) | ty::Slice(ty) => ty,
+                    _ => return None,
+                };
+                iter::zip(l, r)
+                    .map(|(li, ri)| Self::partial_cmp(tcx, cmp_type, li, ri))
+                    .find(|r| r.map_or(true, |o| o != Ordering::Equal))
+                    .unwrap_or_else(|| Some(l.len().cmp(&r.len())))
+            },
             (&Self::Repeat(ref lv, ref ls), &Self::Repeat(ref rv, ref rs)) => {
-                match Self::partial_cmp(tcx, cmp_type, lv, rv) {
+                match Self::partial_cmp(
+                    tcx,
+                    match *cmp_type.kind() {
+                        ty::Array(ty, _) => ty,
+                        _ => return None,
+                    },
+                    lv,
+                    rv,
+                ) {
                     Some(Equal) => Some(ls.cmp(rs)),
                     x => x,
                 }
             },
-            (&Self::Ref(ref lb), &Self::Ref(ref rb)) => Self::partial_cmp(tcx, cmp_type, lb, rb),
+            (&Self::Ref(ref lb), &Self::Ref(ref rb)) => Self::partial_cmp(
+                tcx,
+                match *cmp_type.kind() {
+                    ty::Ref(_, ty, _) => ty,
+                    _ => return None,
+                },
+                lb,
+                rb,
+            ),
             // TODO: are there any useful inter-type orderings?
             _ => None,
         }
diff --git a/src/tools/clippy/clippy_utils/src/eager_or_lazy.rs b/src/tools/clippy/clippy_utils/src/eager_or_lazy.rs
index 8724a4cd651d..95b3e651e2b5 100644
--- a/src/tools/clippy/clippy_utils/src/eager_or_lazy.rs
+++ b/src/tools/clippy/clippy_utils/src/eager_or_lazy.rs
@@ -120,7 +120,7 @@ fn expr_eagerness<'tcx>(cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) -> EagernessS
                             .expr_ty(e)
                             .has_significant_drop(self.cx.tcx, self.cx.param_env)
                         {
-                            self.eagerness = Lazy;
+                            self.eagerness = ForceNoChange;
                             return;
                         }
                     },
diff --git a/src/tools/clippy/clippy_utils/src/lib.rs b/src/tools/clippy/clippy_utils/src/lib.rs
index 7e42fcc6569b..d32cf1a79367 100644
--- a/src/tools/clippy/clippy_utils/src/lib.rs
+++ b/src/tools/clippy/clippy_utils/src/lib.rs
@@ -25,10 +25,12 @@ extern crate rustc_data_structures;
 extern crate rustc_errors;
 extern crate rustc_hir;
 extern crate rustc_hir_typeck;
+extern crate rustc_index;
 extern crate rustc_infer;
 extern crate rustc_lexer;
 extern crate rustc_lint;
 extern crate rustc_middle;
+extern crate rustc_mir_dataflow;
 extern crate rustc_parse_format;
 extern crate rustc_session;
 extern crate rustc_span;
@@ -48,6 +50,7 @@ pub mod eager_or_lazy;
 pub mod higher;
 mod hir_utils;
 pub mod macros;
+pub mod mir;
 pub mod msrvs;
 pub mod numeric_literal;
 pub mod paths;
@@ -122,7 +125,7 @@ pub fn parse_msrv(msrv: &str, sess: Option<&Session>, span: Option<Span>) -> Opt
         return Some(version);
     } else if let Some(sess) = sess {
         if let Some(span) = span {
-            sess.span_err(span, &format!("`{msrv}` is not a valid Rust version"));
+            sess.span_err(span, format!("`{msrv}` is not a valid Rust version"));
         }
     }
     None
@@ -244,7 +247,7 @@ pub fn in_constant(cx: &LateContext<'_>, id: HirId) -> bool {
 /// For example, use this to check whether a function call or a pattern is `Some(..)`.
 pub fn is_res_lang_ctor(cx: &LateContext<'_>, res: Res, lang_item: LangItem) -> bool {
     if let Res::Def(DefKind::Ctor(..), id) = res
-        && let Ok(lang_id) = cx.tcx.lang_items().require(lang_item)
+        && let Some(lang_id) = cx.tcx.lang_items().get(lang_item)
         && let Some(id) = cx.tcx.opt_parent(id)
     {
         id == lang_id
@@ -300,7 +303,7 @@ pub fn is_lang_item_or_ctor(cx: &LateContext<'_>, did: DefId, item: LangItem) ->
         _ => did,
     };
 
-    cx.tcx.lang_items().require(item).map_or(false, |id| id == did)
+    cx.tcx.lang_items().get(item) == Some(did)
 }
 
 pub fn is_unit_expr(expr: &Expr<'_>) -> bool {
@@ -815,13 +818,37 @@ pub fn is_default_equivalent(cx: &LateContext<'_>, e: &Expr<'_>) -> bool {
                 false
             }
         },
-        ExprKind::Call(repl_func, _) => is_default_equivalent_call(cx, repl_func),
+        ExprKind::Call(repl_func, []) => is_default_equivalent_call(cx, repl_func),
+        ExprKind::Call(from_func, [ref arg]) => is_default_equivalent_from(cx, from_func, arg),
         ExprKind::Path(qpath) => is_res_lang_ctor(cx, cx.qpath_res(qpath, e.hir_id), OptionNone),
         ExprKind::AddrOf(rustc_hir::BorrowKind::Ref, _, expr) => matches!(expr.kind, ExprKind::Array([])),
         _ => false,
     }
 }
 
+fn is_default_equivalent_from(cx: &LateContext<'_>, from_func: &Expr<'_>, arg: &Expr<'_>) -> bool {
+    if let ExprKind::Path(QPath::TypeRelative(ty, seg)) = from_func.kind &&
+        seg.ident.name == sym::from
+    {
+        match arg.kind {
+            ExprKind::Lit(hir::Lit {
+                node: LitKind::Str(ref sym, _),
+                ..
+            }) => return sym.is_empty() && is_path_diagnostic_item(cx, ty, sym::String),
+            ExprKind::Array([]) => return is_path_diagnostic_item(cx, ty, sym::Vec),
+            ExprKind::Repeat(_, ArrayLen::Body(len)) => {
+                if let ExprKind::Lit(ref const_lit) = cx.tcx.hir().body(len.body).value.kind &&
+                    let LitKind::Int(v, _) = const_lit.node
+                {
+                        return v == 0 && is_path_diagnostic_item(cx, ty, sym::Vec);
+                }
+            }
+            _ => (),
+        }
+    }
+    false
+}
+
 /// Checks if the top level expression can be moved into a closure as is.
 /// Currently checks for:
 /// * Break/Continue outside the given loop HIR ids.
@@ -1739,6 +1766,7 @@ pub fn any_parent_is_automatically_derived(tcx: TyCtxt<'_>, node: HirId) -> bool
 /// ```rust,ignore
 /// if let Some(args) = match_function_call(cx, cmp_max_call, &paths::CMP_MAX);
 /// ```
+/// This function is deprecated. Use [`match_function_call_with_def_id`].
 pub fn match_function_call<'tcx>(
     cx: &LateContext<'tcx>,
     expr: &'tcx Expr<'_>,
@@ -1756,6 +1784,22 @@ pub fn match_function_call<'tcx>(
     None
 }
 
+pub fn match_function_call_with_def_id<'tcx>(
+    cx: &LateContext<'tcx>,
+    expr: &'tcx Expr<'_>,
+    fun_def_id: DefId,
+) -> Option<&'tcx [Expr<'tcx>]> {
+    if_chain! {
+        if let ExprKind::Call(fun, args) = expr.kind;
+        if let ExprKind::Path(ref qpath) = fun.kind;
+        if cx.qpath_res(qpath, fun.hir_id).opt_def_id() == Some(fun_def_id);
+        then {
+            return Some(args);
+        }
+    };
+    None
+}
+
 /// Checks if the given `DefId` matches any of the paths. Returns the index of matching path, if
 /// any.
 ///
@@ -2237,7 +2281,7 @@ fn with_test_item_names(tcx: TyCtxt<'_>, module: LocalDefId, f: impl Fn(&[Symbol
         Entry::Vacant(entry) => {
             let mut names = Vec::new();
             for id in tcx.hir().module_items(module) {
-                if matches!(tcx.def_kind(id.def_id), DefKind::Const)
+                if matches!(tcx.def_kind(id.owner_id), DefKind::Const)
                     && let item = tcx.hir().item(id)
                     && let ItemKind::Const(ty, _body) = item.kind {
                     if let TyKind::Path(QPath::Resolved(_, path)) = ty.kind {
diff --git a/src/tools/clippy/clippy_utils/src/macros.rs b/src/tools/clippy/clippy_utils/src/macros.rs
index 5a63c290a315..d13b34a66cca 100644
--- a/src/tools/clippy/clippy_utils/src/macros.rs
+++ b/src/tools/clippy/clippy_utils/src/macros.rs
@@ -199,12 +199,12 @@ pub fn first_node_in_macro(cx: &LateContext<'_>, node: &impl HirNode) -> Option<
 pub fn is_panic(cx: &LateContext<'_>, def_id: DefId) -> bool {
     let Some(name) = cx.tcx.get_diagnostic_name(def_id) else { return false };
     matches!(
-        name.as_str(),
-        "core_panic_macro"
-            | "std_panic_macro"
-            | "core_panic_2015_macro"
-            | "std_panic_2015_macro"
-            | "core_panic_2021_macro"
+        name,
+        sym::core_panic_macro
+            | sym::std_panic_macro
+            | sym::core_panic_2015_macro
+            | sym::std_panic_2015_macro
+            | sym::core_panic_2021_macro
     )
 }
 
@@ -627,7 +627,7 @@ pub enum Count<'tcx> {
     /// `FormatParamKind::Numbered`.
     Param(FormatParam<'tcx>),
     /// Not specified.
-    Implied,
+    Implied(Option<Span>),
 }
 
 impl<'tcx> Count<'tcx> {
@@ -638,8 +638,10 @@ impl<'tcx> Count<'tcx> {
         inner: Option<rpf::InnerSpan>,
         values: &FormatArgsValues<'tcx>,
     ) -> Option<Self> {
+        let span = inner.map(|inner| span_from_inner(values.format_string_span, inner));
+
         Some(match count {
-            rpf::Count::CountIs(val) => Self::Is(val, span_from_inner(values.format_string_span, inner?)),
+            rpf::Count::CountIs(val) => Self::Is(val, span?),
             rpf::Count::CountIsName(name, _) => Self::Param(FormatParam::new(
                 FormatParamKind::Named(Symbol::intern(name)),
                 usage,
@@ -661,12 +663,12 @@ impl<'tcx> Count<'tcx> {
                 inner?,
                 values,
             )?),
-            rpf::Count::CountImplied => Self::Implied,
+            rpf::Count::CountImplied => Self::Implied(span),
         })
     }
 
     pub fn is_implied(self) -> bool {
-        matches!(self, Count::Implied)
+        matches!(self, Count::Implied(_))
     }
 
     pub fn param(self) -> Option<FormatParam<'tcx>> {
@@ -675,6 +677,14 @@ impl<'tcx> Count<'tcx> {
             _ => None,
         }
     }
+
+    pub fn span(self) -> Option<Span> {
+        match self {
+            Count::Is(_, span) => Some(span),
+            Count::Param(param) => Some(param.span),
+            Count::Implied(span) => span,
+        }
+    }
 }
 
 /// Specification for the formatting of an argument in the format string. See
@@ -738,8 +748,13 @@ impl<'tcx> FormatSpec<'tcx> {
     /// Returns true if this format spec is unchanged from the default. e.g. returns true for `{}`,
     /// `{foo}` and `{2}`, but false for `{:?}`, `{foo:5}` and `{3:.5}`
     pub fn is_default(&self) -> bool {
-        self.r#trait == sym::Display
-            && self.width.is_implied()
+        self.r#trait == sym::Display && self.is_default_for_trait()
+    }
+
+    /// Has no other formatting specifiers than setting the format trait. returns true for `{}`,
+    /// `{foo}`, `{:?}`, but false for `{foo:5}`, `{3:.5?}`
+    pub fn is_default_for_trait(&self) -> bool {
+        self.width.is_implied()
             && self.precision.is_implied()
             && self.align == Alignment::AlignUnknown
             && self.flags == 0
@@ -757,6 +772,22 @@ pub struct FormatArg<'tcx> {
     pub span: Span,
 }
 
+impl<'tcx> FormatArg<'tcx> {
+    /// Span of the `:` and format specifiers
+    ///
+    /// ```ignore
+    /// format!("{:.}"), format!("{foo:.}")
+    ///           ^^                  ^^
+    /// ```
+    pub fn format_span(&self) -> Span {
+        let base = self.span.data();
+
+        // `base.hi` is `{...}|`, subtract 1 byte (the length of '}') so that it points before the closing
+        // brace `{...|}`
+        Span::new(self.param.span.hi(), base.hi - BytePos(1), base.ctxt, base.parent)
+    }
+}
+
 /// A parsed `format_args!` expansion.
 #[derive(Debug)]
 pub struct FormatArgsExpn<'tcx> {
diff --git a/src/tools/clippy/clippy_utils/src/mir/maybe_storage_live.rs b/src/tools/clippy/clippy_utils/src/mir/maybe_storage_live.rs
new file mode 100644
index 000000000000..d262b335d99d
--- /dev/null
+++ b/src/tools/clippy/clippy_utils/src/mir/maybe_storage_live.rs
@@ -0,0 +1,52 @@
+use rustc_index::bit_set::BitSet;
+use rustc_middle::mir;
+use rustc_mir_dataflow::{AnalysisDomain, CallReturnPlaces, GenKill, GenKillAnalysis};
+
+/// Determines liveness of each local purely based on `StorageLive`/`Dead`.
+#[derive(Copy, Clone)]
+pub(super) struct MaybeStorageLive;
+
+impl<'tcx> AnalysisDomain<'tcx> for MaybeStorageLive {
+    type Domain = BitSet<mir::Local>;
+    const NAME: &'static str = "maybe_storage_live";
+
+    fn bottom_value(&self, body: &mir::Body<'tcx>) -> Self::Domain {
+        // bottom = dead
+        BitSet::new_empty(body.local_decls.len())
+    }
+
+    fn initialize_start_block(&self, body: &mir::Body<'tcx>, state: &mut Self::Domain) {
+        for arg in body.args_iter() {
+            state.insert(arg);
+        }
+    }
+}
+
+impl<'tcx> GenKillAnalysis<'tcx> for MaybeStorageLive {
+    type Idx = mir::Local;
+
+    fn statement_effect(&self, trans: &mut impl GenKill<Self::Idx>, stmt: &mir::Statement<'tcx>, _: mir::Location) {
+        match stmt.kind {
+            mir::StatementKind::StorageLive(l) => trans.gen(l),
+            mir::StatementKind::StorageDead(l) => trans.kill(l),
+            _ => (),
+        }
+    }
+
+    fn terminator_effect(
+        &self,
+        _trans: &mut impl GenKill<Self::Idx>,
+        _terminator: &mir::Terminator<'tcx>,
+        _loc: mir::Location,
+    ) {
+    }
+
+    fn call_return_effect(
+        &self,
+        _trans: &mut impl GenKill<Self::Idx>,
+        _block: mir::BasicBlock,
+        _return_places: CallReturnPlaces<'_, 'tcx>,
+    ) {
+        // Nothing to do when a call returns successfully
+    }
+}
diff --git a/src/tools/clippy/clippy_utils/src/mir/mod.rs b/src/tools/clippy/clippy_utils/src/mir/mod.rs
new file mode 100644
index 000000000000..818e603f665e
--- /dev/null
+++ b/src/tools/clippy/clippy_utils/src/mir/mod.rs
@@ -0,0 +1,164 @@
+use rustc_hir::{Expr, HirId};
+use rustc_middle::mir::visit::{MutatingUseContext, NonMutatingUseContext, PlaceContext, Visitor};
+use rustc_middle::mir::{
+    traversal, Body, InlineAsmOperand, Local, Location, Place, StatementKind, TerminatorKind, START_BLOCK,
+};
+use rustc_middle::ty::TyCtxt;
+
+mod maybe_storage_live;
+
+mod possible_borrower;
+pub use possible_borrower::PossibleBorrowerMap;
+
+mod possible_origin;
+
+mod transitive_relation;
+
+#[derive(Clone, Debug, Default)]
+pub struct LocalUsage {
+    /// The locations where the local is used, if any.
+    pub local_use_locs: Vec<Location>,
+    /// The locations where the local is consumed or mutated, if any.
+    pub local_consume_or_mutate_locs: Vec<Location>,
+}
+
+pub fn visit_local_usage(locals: &[Local], mir: &Body<'_>, location: Location) -> Option<Vec<LocalUsage>> {
+    let init = vec![
+        LocalUsage {
+            local_use_locs: Vec::new(),
+            local_consume_or_mutate_locs: Vec::new(),
+        };
+        locals.len()
+    ];
+
+    traversal::ReversePostorder::new(mir, location.block).try_fold(init, |usage, (tbb, tdata)| {
+        // Give up on loops
+        if tdata.terminator().successors().any(|s| s == location.block) {
+            return None;
+        }
+
+        let mut v = V {
+            locals,
+            location,
+            results: usage,
+        };
+        v.visit_basic_block_data(tbb, tdata);
+        Some(v.results)
+    })
+}
+
+struct V<'a> {
+    locals: &'a [Local],
+    location: Location,
+    results: Vec<LocalUsage>,
+}
+
+impl<'a, 'tcx> Visitor<'tcx> for V<'a> {
+    fn visit_place(&mut self, place: &Place<'tcx>, ctx: PlaceContext, loc: Location) {
+        if loc.block == self.location.block && loc.statement_index <= self.location.statement_index {
+            return;
+        }
+
+        let local = place.local;
+
+        for (i, self_local) in self.locals.iter().enumerate() {
+            if local == *self_local {
+                if !matches!(
+                    ctx,
+                    PlaceContext::MutatingUse(MutatingUseContext::Drop) | PlaceContext::NonUse(_)
+                ) {
+                    self.results[i].local_use_locs.push(loc);
+                }
+                if matches!(
+                    ctx,
+                    PlaceContext::NonMutatingUse(NonMutatingUseContext::Move)
+                        | PlaceContext::MutatingUse(MutatingUseContext::Borrow)
+                ) {
+                    self.results[i].local_consume_or_mutate_locs.push(loc);
+                }
+            }
+        }
+    }
+}
+
+/// Convenience wrapper around `visit_local_usage`.
+pub fn used_exactly_once(mir: &rustc_middle::mir::Body<'_>, local: rustc_middle::mir::Local) -> Option<bool> {
+    visit_local_usage(
+        &[local],
+        mir,
+        Location {
+            block: START_BLOCK,
+            statement_index: 0,
+        },
+    )
+    .map(|mut vec| {
+        let LocalUsage { local_use_locs, .. } = vec.remove(0);
+        local_use_locs
+            .into_iter()
+            .filter(|location| !is_local_assignment(mir, local, *location))
+            .count()
+            == 1
+    })
+}
+
+/// Returns the `mir::Body` containing the node associated with `hir_id`.
+#[allow(clippy::module_name_repetitions)]
+pub fn enclosing_mir(tcx: TyCtxt<'_>, hir_id: HirId) -> &Body<'_> {
+    let body_owner_local_def_id = tcx.hir().enclosing_body_owner(hir_id);
+    tcx.optimized_mir(body_owner_local_def_id.to_def_id())
+}
+
+/// Tries to determine the `Local` corresponding to `expr`, if any.
+/// This function is expensive and should be used sparingly.
+pub fn expr_local(tcx: TyCtxt<'_>, expr: &Expr<'_>) -> Option<Local> {
+    let mir = enclosing_mir(tcx, expr.hir_id);
+    mir.local_decls.iter_enumerated().find_map(|(local, local_decl)| {
+        if local_decl.source_info.span == expr.span {
+            Some(local)
+        } else {
+            None
+        }
+    })
+}
+
+/// Returns a vector of `mir::Location` where `local` is assigned.
+pub fn local_assignments(mir: &Body<'_>, local: Local) -> Vec<Location> {
+    let mut locations = Vec::new();
+    for (block, data) in mir.basic_blocks.iter_enumerated() {
+        for statement_index in 0..=data.statements.len() {
+            let location = Location { block, statement_index };
+            if is_local_assignment(mir, local, location) {
+                locations.push(location);
+            }
+        }
+    }
+    locations
+}
+
+// `is_local_assignment` is based on `is_place_assignment`:
+// https://github.com/rust-lang/rust/blob/b7413511dc85ec01ef4b91785f86614589ac6103/compiler/rustc_middle/src/mir/visit.rs#L1350
+fn is_local_assignment(mir: &Body<'_>, local: Local, location: Location) -> bool {
+    let Location { block, statement_index } = location;
+    let basic_block = &mir.basic_blocks[block];
+    if statement_index < basic_block.statements.len() {
+        let statement = &basic_block.statements[statement_index];
+        if let StatementKind::Assign(box (place, _)) = statement.kind {
+            place.as_local() == Some(local)
+        } else {
+            false
+        }
+    } else {
+        let terminator = basic_block.terminator();
+        match &terminator.kind {
+            TerminatorKind::Call { destination, .. } => destination.as_local() == Some(local),
+            TerminatorKind::InlineAsm { operands, .. } => operands.iter().any(|operand| {
+                if let InlineAsmOperand::Out { place: Some(place), .. } = operand {
+                    place.as_local() == Some(local)
+                } else {
+                    false
+                }
+            }),
+            _ => false,
+        }
+    }
+}
diff --git a/src/tools/clippy/clippy_utils/src/mir/possible_borrower.rs b/src/tools/clippy/clippy_utils/src/mir/possible_borrower.rs
new file mode 100644
index 000000000000..25717bf3d2fe
--- /dev/null
+++ b/src/tools/clippy/clippy_utils/src/mir/possible_borrower.rs
@@ -0,0 +1,241 @@
+use super::{
+    maybe_storage_live::MaybeStorageLive, possible_origin::PossibleOriginVisitor,
+    transitive_relation::TransitiveRelation,
+};
+use crate::ty::is_copy;
+use rustc_data_structures::fx::FxHashMap;
+use rustc_index::bit_set::{BitSet, HybridBitSet};
+use rustc_lint::LateContext;
+use rustc_middle::mir::{self, visit::Visitor as _, Mutability};
+use rustc_middle::ty::{self, visit::TypeVisitor};
+use rustc_mir_dataflow::{Analysis, ResultsCursor};
+use std::ops::ControlFlow;
+
+/// Collects the possible borrowers of each local.
+/// For example, `b = &a; c = &a;` will make `b` and (transitively) `c`
+/// possible borrowers of `a`.
+#[allow(clippy::module_name_repetitions)]
+struct PossibleBorrowerVisitor<'a, 'b, 'tcx> {
+    possible_borrower: TransitiveRelation,
+    body: &'b mir::Body<'tcx>,
+    cx: &'a LateContext<'tcx>,
+    possible_origin: FxHashMap<mir::Local, HybridBitSet<mir::Local>>,
+}
+
+impl<'a, 'b, 'tcx> PossibleBorrowerVisitor<'a, 'b, 'tcx> {
+    fn new(
+        cx: &'a LateContext<'tcx>,
+        body: &'b mir::Body<'tcx>,
+        possible_origin: FxHashMap<mir::Local, HybridBitSet<mir::Local>>,
+    ) -> Self {
+        Self {
+            possible_borrower: TransitiveRelation::default(),
+            cx,
+            body,
+            possible_origin,
+        }
+    }
+
+    fn into_map(
+        self,
+        cx: &'a LateContext<'tcx>,
+        maybe_live: ResultsCursor<'b, 'tcx, MaybeStorageLive>,
+    ) -> PossibleBorrowerMap<'b, 'tcx> {
+        let mut map = FxHashMap::default();
+        for row in (1..self.body.local_decls.len()).map(mir::Local::from_usize) {
+            if is_copy(cx, self.body.local_decls[row].ty) {
+                continue;
+            }
+
+            let mut borrowers = self.possible_borrower.reachable_from(row, self.body.local_decls.len());
+            borrowers.remove(mir::Local::from_usize(0));
+            if !borrowers.is_empty() {
+                map.insert(row, borrowers);
+            }
+        }
+
+        let bs = BitSet::new_empty(self.body.local_decls.len());
+        PossibleBorrowerMap {
+            map,
+            maybe_live,
+            bitset: (bs.clone(), bs),
+        }
+    }
+}
+
+impl<'a, 'b, 'tcx> mir::visit::Visitor<'tcx> for PossibleBorrowerVisitor<'a, 'b, 'tcx> {
+    fn visit_assign(&mut self, place: &mir::Place<'tcx>, rvalue: &mir::Rvalue<'_>, _location: mir::Location) {
+        let lhs = place.local;
+        match rvalue {
+            mir::Rvalue::Ref(_, _, borrowed) => {
+                self.possible_borrower.add(borrowed.local, lhs);
+            },
+            other => {
+                if ContainsRegion
+                    .visit_ty(place.ty(&self.body.local_decls, self.cx.tcx).ty)
+                    .is_continue()
+                {
+                    return;
+                }
+                rvalue_locals(other, |rhs| {
+                    if lhs != rhs {
+                        self.possible_borrower.add(rhs, lhs);
+                    }
+                });
+            },
+        }
+    }
+
+    fn visit_terminator(&mut self, terminator: &mir::Terminator<'_>, _loc: mir::Location) {
+        if let mir::TerminatorKind::Call {
+            args,
+            destination: mir::Place { local: dest, .. },
+            ..
+        } = &terminator.kind
+        {
+            // TODO add doc
+            // If the call returns something with lifetimes,
+            // let's conservatively assume the returned value contains lifetime of all the arguments.
+            // For example, given `let y: Foo<'a> = foo(x)`, `y` is considered to be a possible borrower of `x`.
+
+            let mut immutable_borrowers = vec![];
+            let mut mutable_borrowers = vec![];
+
+            for op in args {
+                match op {
+                    mir::Operand::Copy(p) | mir::Operand::Move(p) => {
+                        if let ty::Ref(_, _, Mutability::Mut) = self.body.local_decls[p.local].ty.kind() {
+                            mutable_borrowers.push(p.local);
+                        } else {
+                            immutable_borrowers.push(p.local);
+                        }
+                    },
+                    mir::Operand::Constant(..) => (),
+                }
+            }
+
+            let mut mutable_variables: Vec<mir::Local> = mutable_borrowers
+                .iter()
+                .filter_map(|r| self.possible_origin.get(r))
+                .flat_map(HybridBitSet::iter)
+                .collect();
+
+            if ContainsRegion.visit_ty(self.body.local_decls[*dest].ty).is_break() {
+                mutable_variables.push(*dest);
+            }
+
+            for y in mutable_variables {
+                for x in &immutable_borrowers {
+                    self.possible_borrower.add(*x, y);
+                }
+                for x in &mutable_borrowers {
+                    self.possible_borrower.add(*x, y);
+                }
+            }
+        }
+    }
+}
+
+struct ContainsRegion;
+
+impl TypeVisitor<'_> for ContainsRegion {
+    type BreakTy = ();
+
+    fn visit_region(&mut self, _: ty::Region<'_>) -> ControlFlow<Self::BreakTy> {
+        ControlFlow::BREAK
+    }
+}
+
+fn rvalue_locals(rvalue: &mir::Rvalue<'_>, mut visit: impl FnMut(mir::Local)) {
+    use rustc_middle::mir::Rvalue::{Aggregate, BinaryOp, Cast, CheckedBinaryOp, Repeat, UnaryOp, Use};
+
+    let mut visit_op = |op: &mir::Operand<'_>| match op {
+        mir::Operand::Copy(p) | mir::Operand::Move(p) => visit(p.local),
+        mir::Operand::Constant(..) => (),
+    };
+
+    match rvalue {
+        Use(op) | Repeat(op, _) | Cast(_, op, _) | UnaryOp(_, op) => visit_op(op),
+        Aggregate(_, ops) => ops.iter().for_each(visit_op),
+        BinaryOp(_, box (lhs, rhs)) | CheckedBinaryOp(_, box (lhs, rhs)) => {
+            visit_op(lhs);
+            visit_op(rhs);
+        },
+        _ => (),
+    }
+}
+
+/// Result of `PossibleBorrowerVisitor`.
+#[allow(clippy::module_name_repetitions)]
+pub struct PossibleBorrowerMap<'b, 'tcx> {
+    /// Mapping `Local -> its possible borrowers`
+    pub map: FxHashMap<mir::Local, HybridBitSet<mir::Local>>,
+    maybe_live: ResultsCursor<'b, 'tcx, MaybeStorageLive>,
+    // Caches to avoid allocation of `BitSet` on every query
+    pub bitset: (BitSet<mir::Local>, BitSet<mir::Local>),
+}
+
+impl<'a, 'b, 'tcx> PossibleBorrowerMap<'b, 'tcx> {
+    pub fn new(cx: &'a LateContext<'tcx>, mir: &'b mir::Body<'tcx>) -> Self {
+        let possible_origin = {
+            let mut vis = PossibleOriginVisitor::new(mir);
+            vis.visit_body(mir);
+            vis.into_map(cx)
+        };
+        let maybe_storage_live_result = MaybeStorageLive
+            .into_engine(cx.tcx, mir)
+            .pass_name("redundant_clone")
+            .iterate_to_fixpoint()
+            .into_results_cursor(mir);
+        let mut vis = PossibleBorrowerVisitor::new(cx, mir, possible_origin);
+        vis.visit_body(mir);
+        vis.into_map(cx, maybe_storage_live_result)
+    }
+
+    /// Returns true if the set of borrowers of `borrowed` living at `at` matches with `borrowers`.
+    pub fn only_borrowers(&mut self, borrowers: &[mir::Local], borrowed: mir::Local, at: mir::Location) -> bool {
+        self.bounded_borrowers(borrowers, borrowers, borrowed, at)
+    }
+
+    /// Returns true if the set of borrowers of `borrowed` living at `at` includes at least `below`
+    /// but no more than `above`.
+    pub fn bounded_borrowers(
+        &mut self,
+        below: &[mir::Local],
+        above: &[mir::Local],
+        borrowed: mir::Local,
+        at: mir::Location,
+    ) -> bool {
+        self.maybe_live.seek_after_primary_effect(at);
+
+        self.bitset.0.clear();
+        let maybe_live = &mut self.maybe_live;
+        if let Some(bitset) = self.map.get(&borrowed) {
+            for b in bitset.iter().filter(move |b| maybe_live.contains(*b)) {
+                self.bitset.0.insert(b);
+            }
+        } else {
+            return false;
+        }
+
+        self.bitset.1.clear();
+        for b in below {
+            self.bitset.1.insert(*b);
+        }
+
+        if !self.bitset.0.superset(&self.bitset.1) {
+            return false;
+        }
+
+        for b in above {
+            self.bitset.0.remove(*b);
+        }
+
+        self.bitset.0.is_empty()
+    }
+
+    pub fn local_is_alive_at(&mut self, local: mir::Local, at: mir::Location) -> bool {
+        self.maybe_live.seek_after_primary_effect(at);
+        self.maybe_live.contains(local)
+    }
+}
diff --git a/src/tools/clippy/clippy_utils/src/mir/possible_origin.rs b/src/tools/clippy/clippy_utils/src/mir/possible_origin.rs
new file mode 100644
index 000000000000..8e7513d740ab
--- /dev/null
+++ b/src/tools/clippy/clippy_utils/src/mir/possible_origin.rs
@@ -0,0 +1,59 @@
+use super::transitive_relation::TransitiveRelation;
+use crate::ty::is_copy;
+use rustc_data_structures::fx::FxHashMap;
+use rustc_index::bit_set::HybridBitSet;
+use rustc_lint::LateContext;
+use rustc_middle::mir;
+
+/// Collect possible borrowed for every `&mut` local.
+/// For example, `_1 = &mut _2` generate _1: {_2,...}
+/// Known Problems: not sure all borrowed are tracked
+#[allow(clippy::module_name_repetitions)]
+pub(super) struct PossibleOriginVisitor<'a, 'tcx> {
+    possible_origin: TransitiveRelation,
+    body: &'a mir::Body<'tcx>,
+}
+
+impl<'a, 'tcx> PossibleOriginVisitor<'a, 'tcx> {
+    pub fn new(body: &'a mir::Body<'tcx>) -> Self {
+        Self {
+            possible_origin: TransitiveRelation::default(),
+            body,
+        }
+    }
+
+    pub fn into_map(self, cx: &LateContext<'tcx>) -> FxHashMap<mir::Local, HybridBitSet<mir::Local>> {
+        let mut map = FxHashMap::default();
+        for row in (1..self.body.local_decls.len()).map(mir::Local::from_usize) {
+            if is_copy(cx, self.body.local_decls[row].ty) {
+                continue;
+            }
+
+            let mut borrowers = self.possible_origin.reachable_from(row, self.body.local_decls.len());
+            borrowers.remove(mir::Local::from_usize(0));
+            if !borrowers.is_empty() {
+                map.insert(row, borrowers);
+            }
+        }
+        map
+    }
+}
+
+impl<'a, 'tcx> mir::visit::Visitor<'tcx> for PossibleOriginVisitor<'a, 'tcx> {
+    fn visit_assign(&mut self, place: &mir::Place<'tcx>, rvalue: &mir::Rvalue<'_>, _location: mir::Location) {
+        let lhs = place.local;
+        match rvalue {
+            // Only consider `&mut`, which can modify origin place
+            mir::Rvalue::Ref(_, rustc_middle::mir::BorrowKind::Mut { .. }, borrowed) |
+            // _2: &mut _;
+            // _3 = move _2
+            mir::Rvalue::Use(mir::Operand::Move(borrowed))  |
+            // _3 = move _2 as &mut _;
+            mir::Rvalue::Cast(_, mir::Operand::Move(borrowed), _)
+                => {
+                self.possible_origin.add(lhs, borrowed.local);
+            },
+            _ => {},
+        }
+    }
+}
diff --git a/src/tools/clippy/clippy_utils/src/mir/transitive_relation.rs b/src/tools/clippy/clippy_utils/src/mir/transitive_relation.rs
new file mode 100644
index 000000000000..7fe2960739fa
--- /dev/null
+++ b/src/tools/clippy/clippy_utils/src/mir/transitive_relation.rs
@@ -0,0 +1,29 @@
+use rustc_data_structures::fx::FxHashMap;
+use rustc_index::bit_set::HybridBitSet;
+use rustc_middle::mir;
+
+#[derive(Default)]
+pub(super) struct TransitiveRelation {
+    relations: FxHashMap<mir::Local, Vec<mir::Local>>,
+}
+
+impl TransitiveRelation {
+    pub fn add(&mut self, a: mir::Local, b: mir::Local) {
+        self.relations.entry(a).or_default().push(b);
+    }
+
+    pub fn reachable_from(&self, a: mir::Local, domain_size: usize) -> HybridBitSet<mir::Local> {
+        let mut seen = HybridBitSet::new_empty(domain_size);
+        let mut stack = vec![a];
+        while let Some(u) = stack.pop() {
+            if let Some(edges) = self.relations.get(&u) {
+                for &v in edges {
+                    if seen.insert(v) {
+                        stack.push(v);
+                    }
+                }
+            }
+        }
+        seen
+    }
+}
diff --git a/src/tools/clippy/clippy_utils/src/numeric_literal.rs b/src/tools/clippy/clippy_utils/src/numeric_literal.rs
index 80098d9766c6..c5dcd7b31f58 100644
--- a/src/tools/clippy/clippy_utils/src/numeric_literal.rs
+++ b/src/tools/clippy/clippy_utils/src/numeric_literal.rs
@@ -69,12 +69,13 @@ impl<'a> NumericLiteral<'a> {
 
     #[must_use]
     pub fn new(lit: &'a str, suffix: Option<&'a str>, float: bool) -> Self {
+        let unsigned_lit = lit.trim_start_matches('-');
         // Determine delimiter for radix prefix, if present, and radix.
-        let radix = if lit.starts_with("0x") {
+        let radix = if unsigned_lit.starts_with("0x") {
             Radix::Hexadecimal
-        } else if lit.starts_with("0b") {
+        } else if unsigned_lit.starts_with("0b") {
             Radix::Binary
-        } else if lit.starts_with("0o") {
+        } else if unsigned_lit.starts_with("0o") {
             Radix::Octal
         } else {
             Radix::Decimal
diff --git a/src/tools/clippy/clippy_utils/src/paths.rs b/src/tools/clippy/clippy_utils/src/paths.rs
index 13938645fc3e..bc8514734304 100644
--- a/src/tools/clippy/clippy_utils/src/paths.rs
+++ b/src/tools/clippy/clippy_utils/src/paths.rs
@@ -16,25 +16,17 @@ pub const APPLICABILITY_VALUES: [[&str; 3]; 4] = [
 #[cfg(feature = "internal")]
 pub const DIAGNOSTIC_BUILDER: [&str; 3] = ["rustc_errors", "diagnostic_builder", "DiagnosticBuilder"];
 pub const ARC_PTR_EQ: [&str; 4] = ["alloc", "sync", "Arc", "ptr_eq"];
-pub const ASMUT_TRAIT: [&str; 3] = ["core", "convert", "AsMut"];
-pub const ASREF_TRAIT: [&str; 3] = ["core", "convert", "AsRef"];
 pub const BTREEMAP_CONTAINS_KEY: [&str; 6] = ["alloc", "collections", "btree", "map", "BTreeMap", "contains_key"];
-pub const BTREEMAP_ENTRY: [&str; 6] = ["alloc", "collections", "btree", "map", "entry", "Entry"];
 pub const BTREEMAP_INSERT: [&str; 6] = ["alloc", "collections", "btree", "map", "BTreeMap", "insert"];
 pub const BTREESET_ITER: [&str; 6] = ["alloc", "collections", "btree", "set", "BTreeSet", "iter"];
 pub const CLONE_TRAIT_METHOD: [&str; 4] = ["core", "clone", "Clone", "clone"];
-pub const COW: [&str; 3] = ["alloc", "borrow", "Cow"];
 pub const CORE_ITER_COLLECT: [&str; 6] = ["core", "iter", "traits", "iterator", "Iterator", "collect"];
 pub const CORE_ITER_CLONED: [&str; 6] = ["core", "iter", "traits", "iterator", "Iterator", "cloned"];
 pub const CORE_ITER_COPIED: [&str; 6] = ["core", "iter", "traits", "iterator", "Iterator", "copied"];
 pub const CORE_ITER_FILTER: [&str; 6] = ["core", "iter", "traits", "iterator", "Iterator", "filter"];
-pub const CORE_ITER_INTO_ITER: [&str; 6] = ["core", "iter", "traits", "collect", "IntoIterator", "into_iter"];
 pub const CSTRING_AS_C_STR: [&str; 5] = ["alloc", "ffi", "c_str", "CString", "as_c_str"];
 pub const DEFAULT_TRAIT_METHOD: [&str; 4] = ["core", "default", "Default", "default"];
 pub const DEREF_MUT_TRAIT_METHOD: [&str; 5] = ["core", "ops", "deref", "DerefMut", "deref_mut"];
-/// Preferably use the diagnostic item `sym::deref_method` where possible
-pub const DEREF_TRAIT_METHOD: [&str; 5] = ["core", "ops", "deref", "Deref", "deref"];
-pub const DISPLAY_TRAIT: [&str; 3] = ["core", "fmt", "Display"];
 #[cfg(feature = "internal")]
 pub const EARLY_CONTEXT: [&str; 2] = ["rustc_lint", "EarlyContext"];
 #[cfg(feature = "internal")]
@@ -42,30 +34,22 @@ pub const EARLY_LINT_PASS: [&str; 3] = ["rustc_lint", "passes", "EarlyLintPass"]
 pub const EXIT: [&str; 3] = ["std", "process", "exit"];
 pub const F32_EPSILON: [&str; 4] = ["core", "f32", "<impl f32>", "EPSILON"];
 pub const F64_EPSILON: [&str; 4] = ["core", "f64", "<impl f64>", "EPSILON"];
-pub const FILE: [&str; 3] = ["std", "fs", "File"];
-pub const FILE_TYPE: [&str; 3] = ["std", "fs", "FileType"];
-pub const FROM_FROM: [&str; 4] = ["core", "convert", "From", "from"];
 pub const FROM_ITERATOR_METHOD: [&str; 6] = ["core", "iter", "traits", "collect", "FromIterator", "from_iter"];
 pub const FROM_STR_METHOD: [&str; 5] = ["core", "str", "traits", "FromStr", "from_str"];
-pub const FUTURE_FROM_GENERATOR: [&str; 3] = ["core", "future", "from_generator"];
 #[expect(clippy::invalid_paths)] // internal lints do not know about all external crates
 pub const FUTURES_IO_ASYNCREADEXT: [&str; 3] = ["futures_util", "io", "AsyncReadExt"];
 #[expect(clippy::invalid_paths)] // internal lints do not know about all external crates
 pub const FUTURES_IO_ASYNCWRITEEXT: [&str; 3] = ["futures_util", "io", "AsyncWriteExt"];
 pub const HASHMAP_CONTAINS_KEY: [&str; 6] = ["std", "collections", "hash", "map", "HashMap", "contains_key"];
-pub const HASHMAP_ENTRY: [&str; 5] = ["std", "collections", "hash", "map", "Entry"];
 pub const HASHMAP_INSERT: [&str; 6] = ["std", "collections", "hash", "map", "HashMap", "insert"];
 pub const HASHSET_ITER: [&str; 6] = ["std", "collections", "hash", "set", "HashSet", "iter"];
 #[cfg(feature = "internal")]
 pub const IDENT: [&str; 3] = ["rustc_span", "symbol", "Ident"];
 #[cfg(feature = "internal")]
 pub const IDENT_AS_STR: [&str; 4] = ["rustc_span", "symbol", "Ident", "as_str"];
-pub const INDEX: [&str; 3] = ["core", "ops", "Index"];
-pub const INDEX_MUT: [&str; 3] = ["core", "ops", "IndexMut"];
 pub const INSERT_STR: [&str; 4] = ["alloc", "string", "String", "insert_str"];
 pub const ITER_COUNT: [&str; 6] = ["core", "iter", "traits", "iterator", "Iterator", "count"];
 pub const ITER_EMPTY: [&str; 5] = ["core", "iter", "sources", "empty", "Empty"];
-pub const ITER_REPEAT: [&str; 5] = ["core", "iter", "sources", "repeat", "repeat"];
 pub const ITERTOOLS_NEXT_TUPLE: [&str; 3] = ["itertools", "Itertools", "next_tuple"];
 #[cfg(feature = "internal")]
 pub const KW_MODULE: [&str; 3] = ["rustc_span", "symbol", "kw"];
@@ -76,13 +60,7 @@ pub const LATE_LINT_PASS: [&str; 3] = ["rustc_lint", "passes", "LateLintPass"];
 #[cfg(feature = "internal")]
 pub const LINT: [&str; 2] = ["rustc_lint_defs", "Lint"];
 pub const MEM_SWAP: [&str; 3] = ["core", "mem", "swap"];
-pub const MUTEX_GUARD: [&str; 4] = ["std", "sync", "mutex", "MutexGuard"];
 pub const OPEN_OPTIONS: [&str; 3] = ["std", "fs", "OpenOptions"];
-/// Preferably use the diagnostic item `sym::Option` where possible
-pub const OPTION: [&str; 3] = ["core", "option", "Option"];
-pub const OPTION_NONE: [&str; 4] = ["core", "option", "Option", "None"];
-pub const OPTION_SOME: [&str; 4] = ["core", "option", "Option", "Some"];
-pub const ORD: [&str; 3] = ["core", "cmp", "Ord"];
 pub const OS_STRING_AS_OS_STR: [&str; 5] = ["std", "ffi", "os_str", "OsString", "as_os_str"];
 pub const OS_STR_TO_OS_STRING: [&str; 5] = ["std", "ffi", "os_str", "OsStr", "to_os_string"];
 pub const PARKING_LOT_MUTEX_GUARD: [&str; 3] = ["lock_api", "mutex", "MutexGuard"];
@@ -95,8 +73,6 @@ pub const PERMISSIONS: [&str; 3] = ["std", "fs", "Permissions"];
 #[cfg_attr(not(unix), allow(clippy::invalid_paths))]
 pub const PERMISSIONS_FROM_MODE: [&str; 6] = ["std", "os", "unix", "fs", "PermissionsExt", "from_mode"];
 pub const POLL: [&str; 4] = ["core", "task", "poll", "Poll"];
-pub const POLL_PENDING: [&str; 5] = ["core", "task", "poll", "Poll", "Pending"];
-pub const POLL_READY: [&str; 5] = ["core", "task", "poll", "Poll", "Ready"];
 pub const PTR_COPY: [&str; 3] = ["core", "intrinsics", "copy"];
 pub const PTR_COPY_NONOVERLAPPING: [&str; 3] = ["core", "intrinsics", "copy_nonoverlapping"];
 pub const PTR_EQ: [&str; 3] = ["core", "ptr", "eq"];
@@ -119,26 +95,14 @@ pub const RANGE_ARGUMENT_TRAIT: [&str; 3] = ["core", "ops", "RangeBounds"];
 pub const RC_PTR_EQ: [&str; 4] = ["alloc", "rc", "Rc", "ptr_eq"];
 pub const REFCELL_REF: [&str; 3] = ["core", "cell", "Ref"];
 pub const REFCELL_REFMUT: [&str; 3] = ["core", "cell", "RefMut"];
-#[expect(clippy::invalid_paths)] // internal lints do not know about all external crates
 pub const REGEX_BUILDER_NEW: [&str; 5] = ["regex", "re_builder", "unicode", "RegexBuilder", "new"];
-#[expect(clippy::invalid_paths)] // internal lints do not know about all external crates
 pub const REGEX_BYTES_BUILDER_NEW: [&str; 5] = ["regex", "re_builder", "bytes", "RegexBuilder", "new"];
-#[expect(clippy::invalid_paths)] // internal lints do not know about all external crates
 pub const REGEX_BYTES_NEW: [&str; 4] = ["regex", "re_bytes", "Regex", "new"];
-#[expect(clippy::invalid_paths)] // internal lints do not know about all external crates
 pub const REGEX_BYTES_SET_NEW: [&str; 5] = ["regex", "re_set", "bytes", "RegexSet", "new"];
-#[expect(clippy::invalid_paths)] // internal lints do not know about all external crates
 pub const REGEX_NEW: [&str; 4] = ["regex", "re_unicode", "Regex", "new"];
-#[expect(clippy::invalid_paths)] // internal lints do not know about all external crates
 pub const REGEX_SET_NEW: [&str; 5] = ["regex", "re_set", "unicode", "RegexSet", "new"];
-/// Preferably use the diagnostic item `sym::Result` where possible
-pub const RESULT: [&str; 3] = ["core", "result", "Result"];
-pub const RESULT_ERR: [&str; 4] = ["core", "result", "Result", "Err"];
-pub const RESULT_OK: [&str; 4] = ["core", "result", "Result", "Ok"];
 #[cfg(feature = "internal")]
 pub const RUSTC_VERSION: [&str; 2] = ["rustc_semver", "RustcVersion"];
-pub const RWLOCK_READ_GUARD: [&str; 4] = ["std", "sync", "rwlock", "RwLockReadGuard"];
-pub const RWLOCK_WRITE_GUARD: [&str; 4] = ["std", "sync", "rwlock", "RwLockWriteGuard"];
 pub const SERDE_DESERIALIZE: [&str; 3] = ["serde", "de", "Deserialize"];
 pub const SERDE_DE_VISITOR: [&str; 3] = ["serde", "de", "Visitor"];
 pub const SLICE_FROM_RAW_PARTS: [&str; 4] = ["core", "slice", "raw", "from_raw_parts"];
diff --git a/src/tools/clippy/clippy_utils/src/sugg.rs b/src/tools/clippy/clippy_utils/src/sugg.rs
index 5089987ef720..eefba8cd29c4 100644
--- a/src/tools/clippy/clippy_utils/src/sugg.rs
+++ b/src/tools/clippy/clippy_utils/src/sugg.rs
@@ -1,7 +1,9 @@
 //! Contains utility functions to generate suggestions.
 #![deny(clippy::missing_docs_in_private_items)]
 
-use crate::source::{snippet, snippet_opt, snippet_with_applicability, snippet_with_macro_callsite};
+use crate::source::{
+    snippet, snippet_opt, snippet_with_applicability, snippet_with_context, snippet_with_macro_callsite,
+};
 use crate::ty::expr_sig;
 use crate::{get_parent_expr_for_hir, higher};
 use rustc_ast::util::parser::AssocOp;
@@ -110,7 +112,7 @@ impl<'a> Sugg<'a> {
         if expr.span.ctxt() == ctxt {
             Self::hir_from_snippet(expr, |span| snippet(cx, span, default))
         } else {
-            let snip = snippet_with_applicability(cx, expr.span, default, applicability);
+            let (snip, _) = snippet_with_context(cx, expr.span, ctxt, default, applicability);
             Sugg::NonParen(snip)
         }
     }
@@ -205,6 +207,7 @@ impl<'a> Sugg<'a> {
             | ast::ExprKind::InlineAsm(..)
             | ast::ExprKind::ConstBlock(..)
             | ast::ExprKind::Lit(..)
+            | ast::ExprKind::IncludedBytes(..)
             | ast::ExprKind::Loop(..)
             | ast::ExprKind::MacCall(..)
             | ast::ExprKind::MethodCall(..)
@@ -1052,12 +1055,7 @@ impl<'tcx> Delegate<'tcx> for DerefDelegate<'_, 'tcx> {
 
     fn mutate(&mut self, _: &PlaceWithHirId<'tcx>, _: HirId) {}
 
-    fn fake_read(
-        &mut self,
-        _: &rustc_hir_typeck::expr_use_visitor::PlaceWithHirId<'tcx>,
-        _: FakeReadCause,
-        _: HirId,
-    ) {}
+    fn fake_read(&mut self, _: &PlaceWithHirId<'tcx>, _: FakeReadCause, _: HirId) {}
 }
 
 #[cfg(test)]
diff --git a/src/tools/clippy/clippy_utils/src/ty.rs b/src/tools/clippy/clippy_utils/src/ty.rs
index 3b5a9ba83568..3a144c2bb223 100644
--- a/src/tools/clippy/clippy_utils/src/ty.rs
+++ b/src/tools/clippy/clippy_utils/src/ty.rs
@@ -18,7 +18,7 @@ use rustc_middle::ty::{
 };
 use rustc_middle::ty::{GenericArg, GenericArgKind};
 use rustc_span::symbol::Ident;
-use rustc_span::{sym, Span, Symbol, DUMMY_SP};
+use rustc_span::{sym, Span, Symbol};
 use rustc_target::abi::{Size, VariantIdx};
 use rustc_trait_selection::infer::InferCtxtExt;
 use rustc_trait_selection::traits::query::normalize::AtExt;
@@ -28,7 +28,7 @@ use crate::{match_def_path, path_res, paths};
 
 // Checks if the given type implements copy.
 pub fn is_copy<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>) -> bool {
-    ty.is_copy_modulo_regions(cx.tcx.at(DUMMY_SP), cx.param_env)
+    ty.is_copy_modulo_regions(cx.tcx, cx.param_env)
 }
 
 /// This checks whether a given type is known to implement Debug.
@@ -318,11 +318,7 @@ pub fn is_type_diagnostic_item(cx: &LateContext<'_>, ty: Ty<'_>, diag_item: Symb
 /// Returns `false` if the `LangItem` is not defined.
 pub fn is_type_lang_item(cx: &LateContext<'_>, ty: Ty<'_>, lang_item: hir::LangItem) -> bool {
     match ty.kind() {
-        ty::Adt(adt, _) => cx
-            .tcx
-            .lang_items()
-            .require(lang_item)
-            .map_or(false, |li| li == adt.did()),
+        ty::Adt(adt, _) => cx.tcx.lang_items().get(lang_item) == Some(adt.did()),
         _ => false,
     }
 }
diff --git a/src/tools/clippy/lintcheck/src/config.rs b/src/tools/clippy/lintcheck/src/config.rs
index b344db634f61..b8824024e6c7 100644
--- a/src/tools/clippy/lintcheck/src/config.rs
+++ b/src/tools/clippy/lintcheck/src/config.rs
@@ -73,8 +73,7 @@ impl LintcheckConfig {
         let sources_toml = env::var("LINTCHECK_TOML").unwrap_or_else(|_| {
             clap_config
                 .get_one::<String>("crates-toml")
-                .map(|s| &**s)
-                .unwrap_or("lintcheck/lintcheck_crates.toml")
+                .map_or("lintcheck/lintcheck_crates.toml", |s| &**s)
                 .into()
         });
 
@@ -97,7 +96,7 @@ impl LintcheckConfig {
             Some(&0) => {
                 // automatic choice
                 // Rayon seems to return thread count so half that for core count
-                (rayon::current_num_threads() / 2) as usize
+                rayon::current_num_threads() / 2
             },
             Some(&threads) => threads,
             // no -j passed, use a single thread
diff --git a/src/tools/clippy/lintcheck/src/driver.rs b/src/tools/clippy/lintcheck/src/driver.rs
index 63221bab32d3..47724a2fedb0 100644
--- a/src/tools/clippy/lintcheck/src/driver.rs
+++ b/src/tools/clippy/lintcheck/src/driver.rs
@@ -5,7 +5,7 @@ use std::net::TcpStream;
 use std::process::{self, Command, Stdio};
 use std::{env, mem};
 
-/// 1. Sends [DriverInfo] to the [crate::recursive::LintcheckServer] running on `addr`
+/// 1. Sends [`DriverInfo`] to the [`crate::recursive::LintcheckServer`] running on `addr`
 /// 2. Receives [bool] from the server, if `false` returns `None`
 /// 3. Otherwise sends the stderr of running `clippy-driver` to the server
 fn run_clippy(addr: &str) -> Option<i32> {
diff --git a/src/tools/clippy/lintcheck/src/main.rs b/src/tools/clippy/lintcheck/src/main.rs
index cc2b3e1acec7..54c1b80c42db 100644
--- a/src/tools/clippy/lintcheck/src/main.rs
+++ b/src/tools/clippy/lintcheck/src/main.rs
@@ -116,12 +116,13 @@ impl ClippyWarning {
 
         let span = diag.spans.into_iter().find(|span| span.is_primary)?;
 
-        let file = match Path::new(&span.file_name).strip_prefix(env!("CARGO_HOME")) {
-            Ok(stripped) => format!("$CARGO_HOME/{}", stripped.display()),
-            Err(_) => format!(
+        let file = if let Ok(stripped) = Path::new(&span.file_name).strip_prefix(env!("CARGO_HOME")) {
+            format!("$CARGO_HOME/{}", stripped.display())
+        } else {
+            format!(
                 "target/lintcheck/sources/{}-{}/{}",
                 crate_name, crate_version, span.file_name
-            ),
+            )
         };
 
         Some(Self {
@@ -144,16 +145,17 @@ impl ClippyWarning {
             }
 
             let mut output = String::from("| ");
-            let _ = write!(output, "[`{}`]({}#L{})", file_with_pos, file, self.line);
+            let _ = write!(output, "[`{file_with_pos}`]({file}#L{})", self.line);
             let _ = write!(output, r#" | `{:<50}` | "{}" |"#, self.lint_type, self.message);
             output.push('\n');
             output
         } else {
-            format!("{} {} \"{}\"\n", file_with_pos, self.lint_type, self.message)
+            format!("{file_with_pos} {} \"{}\"\n", self.lint_type, self.message)
         }
     }
 }
 
+#[allow(clippy::result_large_err)]
 fn get(path: &str) -> Result<ureq::Response, ureq::Error> {
     const MAX_RETRIES: u8 = 4;
     let mut retries = 0;
@@ -161,11 +163,11 @@ fn get(path: &str) -> Result<ureq::Response, ureq::Error> {
         match ureq::get(path).call() {
             Ok(res) => return Ok(res),
             Err(e) if retries >= MAX_RETRIES => return Err(e),
-            Err(ureq::Error::Transport(e)) => eprintln!("Error: {}", e),
+            Err(ureq::Error::Transport(e)) => eprintln!("Error: {e}"),
             Err(e) => return Err(e),
         }
-        eprintln!("retrying in {} seconds...", retries);
-        thread::sleep(Duration::from_secs(retries as u64));
+        eprintln!("retrying in {retries} seconds...");
+        thread::sleep(Duration::from_secs(u64::from(retries)));
         retries += 1;
     }
 }
@@ -181,11 +183,11 @@ impl CrateSource {
                 let krate_download_dir = PathBuf::from(LINTCHECK_DOWNLOADS);
 
                 // url to download the crate from crates.io
-                let url = format!("https://crates.io/api/v1/crates/{}/{}/download", name, version);
-                println!("Downloading and extracting {} {} from {}", name, version, url);
+                let url = format!("https://crates.io/api/v1/crates/{name}/{version}/download");
+                println!("Downloading and extracting {name} {version} from {url}");
                 create_dirs(&krate_download_dir, &extract_dir);
 
-                let krate_file_path = krate_download_dir.join(format!("{}-{}.crate.tar.gz", name, version));
+                let krate_file_path = krate_download_dir.join(format!("{name}-{version}.crate.tar.gz"));
                 // don't download/extract if we already have done so
                 if !krate_file_path.is_file() {
                     // create a file path to download and write the crate data into
@@ -205,7 +207,7 @@ impl CrateSource {
                 Crate {
                     version: version.clone(),
                     name: name.clone(),
-                    path: extract_dir.join(format!("{}-{}/", name, version)),
+                    path: extract_dir.join(format!("{name}-{version}/")),
                     options: options.clone(),
                 }
             },
@@ -218,12 +220,12 @@ impl CrateSource {
                 let repo_path = {
                     let mut repo_path = PathBuf::from(LINTCHECK_SOURCES);
                     // add a -git suffix in case we have the same crate from crates.io and a git repo
-                    repo_path.push(format!("{}-git", name));
+                    repo_path.push(format!("{name}-git"));
                     repo_path
                 };
                 // clone the repo if we have not done so
                 if !repo_path.is_dir() {
-                    println!("Cloning {} and checking out {}", url, commit);
+                    println!("Cloning {url} and checking out {commit}");
                     if !Command::new("git")
                         .arg("clone")
                         .arg(url)
@@ -232,7 +234,7 @@ impl CrateSource {
                         .expect("Failed to clone git repo!")
                         .success()
                     {
-                        eprintln!("Failed to clone {} into {}", url, repo_path.display())
+                        eprintln!("Failed to clone {url} into {}", repo_path.display());
                     }
                 }
                 // check out the commit/branch/whatever
@@ -245,7 +247,7 @@ impl CrateSource {
                     .expect("Failed to check out commit")
                     .success()
                 {
-                    eprintln!("Failed to checkout {} of repo at {}", commit, repo_path.display())
+                    eprintln!("Failed to checkout {commit} of repo at {}", repo_path.display());
                 }
 
                 Crate {
@@ -256,23 +258,23 @@ impl CrateSource {
                 }
             },
             CrateSource::Path { name, path, options } => {
-                // copy path into the dest_crate_root but skip directories that contain a CACHEDIR.TAG file.
-                // The target/ directory contains a CACHEDIR.TAG file so it is the most commonly skipped directory
-                // as a result of this filter.
-                let dest_crate_root = PathBuf::from(LINTCHECK_SOURCES).join(name);
-                if dest_crate_root.exists() {
-                    println!("Deleting existing directory at {:?}", dest_crate_root);
-                    std::fs::remove_dir_all(&dest_crate_root).unwrap();
-                }
-
-                println!("Copying {:?} to {:?}", path, dest_crate_root);
-
                 fn is_cache_dir(entry: &DirEntry) -> bool {
                     std::fs::read(entry.path().join("CACHEDIR.TAG"))
                         .map(|x| x.starts_with(b"Signature: 8a477f597d28d172789f06886806bc55"))
                         .unwrap_or(false)
                 }
 
+                // copy path into the dest_crate_root but skip directories that contain a CACHEDIR.TAG file.
+                // The target/ directory contains a CACHEDIR.TAG file so it is the most commonly skipped directory
+                // as a result of this filter.
+                let dest_crate_root = PathBuf::from(LINTCHECK_SOURCES).join(name);
+                if dest_crate_root.exists() {
+                    println!("Deleting existing directory at {dest_crate_root:?}");
+                    std::fs::remove_dir_all(&dest_crate_root).unwrap();
+                }
+
+                println!("Copying {path:?} to {dest_crate_root:?}");
+
                 for entry in WalkDir::new(path).into_iter().filter_entry(|e| !is_cache_dir(e)) {
                     let entry = entry.unwrap();
                     let entry_path = entry.path();
@@ -301,6 +303,7 @@ impl CrateSource {
 impl Crate {
     /// Run `cargo clippy` on the `Crate` and collect and return all the lint warnings that clippy
     /// issued
+    #[allow(clippy::too_many_arguments)]
     fn run_clippy_lints(
         &self,
         cargo_clippy_path: &Path,
@@ -345,14 +348,14 @@ impl Crate {
                 clippy_args.push(opt);
             }
         } else {
-            clippy_args.extend(&["-Wclippy::pedantic", "-Wclippy::cargo"])
+            clippy_args.extend(["-Wclippy::pedantic", "-Wclippy::cargo"]);
         }
 
         if lint_filter.is_empty() {
             clippy_args.push("--cap-lints=warn");
         } else {
             clippy_args.push("--cap-lints=allow");
-            clippy_args.extend(lint_filter.iter().map(|filter| filter.as_str()))
+            clippy_args.extend(lint_filter.iter().map(std::string::String::as_str));
         }
 
         if let Some(server) = server {
@@ -389,10 +392,7 @@ impl Crate {
 
         let all_output = Command::new(&cargo_clippy_path)
             // use the looping index to create individual target dirs
-            .env(
-                "CARGO_TARGET_DIR",
-                shared_target_dir.join(format!("_{:?}", thread_index)),
-            )
+            .env("CARGO_TARGET_DIR", shared_target_dir.join(format!("_{thread_index:?}")))
             .args(&cargo_clippy_args)
             .current_dir(&self.path)
             .output()
@@ -422,8 +422,8 @@ impl Crate {
             {
                 let subcrate = &stderr[63..];
                 println!(
-                    "ERROR: failed to apply some suggetion to {} / to (sub)crate {}",
-                    self.name, subcrate
+                    "ERROR: failed to apply some suggetion to {} / to (sub)crate {subcrate}",
+                    self.name
                 );
             }
             // fast path, we don't need the warnings anyway
@@ -457,20 +457,16 @@ fn build_clippy() {
 /// Read a `lintcheck_crates.toml` file
 fn read_crates(toml_path: &Path) -> (Vec<CrateSource>, RecursiveOptions) {
     let toml_content: String =
-        std::fs::read_to_string(&toml_path).unwrap_or_else(|_| panic!("Failed to read {}", toml_path.display()));
+        std::fs::read_to_string(toml_path).unwrap_or_else(|_| panic!("Failed to read {}", toml_path.display()));
     let crate_list: SourceList =
-        toml::from_str(&toml_content).unwrap_or_else(|e| panic!("Failed to parse {}: \n{}", toml_path.display(), e));
+        toml::from_str(&toml_content).unwrap_or_else(|e| panic!("Failed to parse {}: \n{e}", toml_path.display()));
     // parse the hashmap of the toml file into a list of crates
-    let tomlcrates: Vec<TomlCrate> = crate_list
-        .crates
-        .into_iter()
-        .map(|(_cratename, tomlcrate)| tomlcrate)
-        .collect();
+    let tomlcrates: Vec<TomlCrate> = crate_list.crates.into_values().collect();
 
     // flatten TomlCrates into CrateSources (one TomlCrates may represent several versions of a crate =>
     // multiple Cratesources)
     let mut crate_sources = Vec::new();
-    tomlcrates.into_iter().for_each(|tk| {
+    for tk in tomlcrates {
         if let Some(ref path) = tk.path {
             crate_sources.push(CrateSource::Path {
                 name: tk.name.clone(),
@@ -479,13 +475,13 @@ fn read_crates(toml_path: &Path) -> (Vec<CrateSource>, RecursiveOptions) {
             });
         } else if let Some(ref versions) = tk.versions {
             // if we have multiple versions, save each one
-            versions.iter().for_each(|ver| {
+            for ver in versions.iter() {
                 crate_sources.push(CrateSource::CratesIo {
                     name: tk.name.clone(),
                     version: ver.to_string(),
                     options: tk.options.clone(),
                 });
-            })
+            }
         } else if tk.git_url.is_some() && tk.git_hash.is_some() {
             // otherwise, we should have a git source
             crate_sources.push(CrateSource::Git {
@@ -502,16 +498,19 @@ fn read_crates(toml_path: &Path) -> (Vec<CrateSource>, RecursiveOptions) {
         if tk.versions.is_some() && (tk.git_url.is_some() || tk.git_hash.is_some())
             || tk.git_hash.is_some() != tk.git_url.is_some()
         {
-            eprintln!("tomlkrate: {:?}", tk);
-            if tk.git_hash.is_some() != tk.git_url.is_some() {
-                panic!("Error: Encountered TomlCrate with only one of git_hash and git_url!");
-            }
-            if tk.path.is_some() && (tk.git_hash.is_some() || tk.versions.is_some()) {
-                panic!("Error: TomlCrate can only have one of 'git_.*', 'version' or 'path' fields");
-            }
+            eprintln!("tomlkrate: {tk:?}");
+            assert_eq!(
+                tk.git_hash.is_some(),
+                tk.git_url.is_some(),
+                "Error: Encountered TomlCrate with only one of git_hash and git_url!"
+            );
+            assert!(
+                tk.path.is_none() || (tk.git_hash.is_none() && tk.versions.is_none()),
+                "Error: TomlCrate can only have one of 'git_.*', 'version' or 'path' fields"
+            );
             unreachable!("Failed to translate TomlCrate into CrateSource!");
         }
-    });
+    }
     // sort the crates
     crate_sources.sort();
 
@@ -530,13 +529,13 @@ fn gather_stats(clippy_warnings: &[ClippyWarning]) -> (String, HashMap<&String,
     let mut stats: Vec<(&&String, &usize)> = counter.iter().map(|(lint, count)| (lint, count)).collect();
     // sort by "000{count} {clippy::lintname}"
     // to not have a lint with 200 and 2 warnings take the same spot
-    stats.sort_by_key(|(lint, count)| format!("{:0>4}, {}", count, lint));
+    stats.sort_by_key(|(lint, count)| format!("{count:0>4}, {lint}"));
 
     let mut header = String::from("| lint                                               | count |\n");
     header.push_str("| -------------------------------------------------- | ----- |\n");
     let stats_string = stats
         .iter()
-        .map(|(lint, count)| format!("| {:<50} |  {:>4} |\n", lint, count))
+        .map(|(lint, count)| format!("| {lint:<50} |  {count:>4} |\n"))
         .fold(header, |mut table, line| {
             table.push_str(&line);
             table
@@ -573,6 +572,7 @@ fn lintcheck_needs_rerun(lintcheck_logs_path: &Path, paths: [&Path; 2]) -> bool
     logs_modified < clippy_modified
 }
 
+#[allow(clippy::too_many_lines)]
 fn main() {
     // We're being executed as a `RUSTC_WRAPPER` as part of `--recursive`
     if let Ok(addr) = env::var("LINTCHECK_SERVER") {
@@ -602,10 +602,10 @@ fn main() {
     ) {
         let shared_target_dir = "target/lintcheck/shared_target_dir";
         // if we get an Err here, the shared target dir probably does simply not exist
-        if let Ok(metadata) = std::fs::metadata(&shared_target_dir) {
+        if let Ok(metadata) = std::fs::metadata(shared_target_dir) {
             if metadata.is_dir() {
                 println!("Clippy is newer than lint check logs, clearing lintcheck shared target dir...");
-                std::fs::remove_dir_all(&shared_target_dir)
+                std::fs::remove_dir_all(shared_target_dir)
                     .expect("failed to remove target/lintcheck/shared_target_dir");
             }
         }
@@ -678,7 +678,7 @@ fn main() {
         .unwrap();
 
     let server = config.recursive.then(|| {
-        let _ = fs::remove_dir_all("target/lintcheck/shared_target_dir/recursive");
+        fs::remove_dir_all("target/lintcheck/shared_target_dir/recursive").unwrap_or_default();
 
         LintcheckServer::spawn(recursive_options)
     });
@@ -734,8 +734,8 @@ fn main() {
     }
     write!(text, "{}", all_msgs.join("")).unwrap();
     text.push_str("\n\n### ICEs:\n");
-    for (cratename, msg) in ices.iter() {
-        let _ = write!(text, "{}: '{}'", cratename, msg);
+    for (cratename, msg) in &ices {
+        let _ = write!(text, "{cratename}: '{msg}'");
     }
 
     println!("Writing logs to {}", config.lintcheck_results_path.display());
@@ -779,7 +779,7 @@ fn read_stats_from_file(file_path: &Path) -> HashMap<String, usize> {
 fn print_stats(old_stats: HashMap<String, usize>, new_stats: HashMap<&String, usize>, lint_filter: &Vec<String>) {
     let same_in_both_hashmaps = old_stats
         .iter()
-        .filter(|(old_key, old_val)| new_stats.get::<&String>(&old_key) == Some(old_val))
+        .filter(|(old_key, old_val)| new_stats.get::<&String>(old_key) == Some(old_val))
         .map(|(k, v)| (k.to_string(), *v))
         .collect::<Vec<(String, usize)>>();
 
@@ -787,37 +787,37 @@ fn print_stats(old_stats: HashMap<String, usize>, new_stats: HashMap<&String, us
     let mut new_stats_deduped = new_stats;
 
     // remove duplicates from both hashmaps
-    same_in_both_hashmaps.iter().for_each(|(k, v)| {
+    for (k, v) in &same_in_both_hashmaps {
         assert!(old_stats_deduped.remove(k) == Some(*v));
         assert!(new_stats_deduped.remove(k) == Some(*v));
-    });
+    }
 
     println!("\nStats:");
 
     // list all new counts  (key is in new stats but not in old stats)
     new_stats_deduped
         .iter()
-        .filter(|(new_key, _)| old_stats_deduped.get::<str>(&new_key).is_none())
+        .filter(|(new_key, _)| old_stats_deduped.get::<str>(new_key).is_none())
         .for_each(|(new_key, new_value)| {
-            println!("{} 0 => {}", new_key, new_value);
+            println!("{new_key} 0 => {new_value}");
         });
 
     // list all changed counts (key is in both maps but value differs)
     new_stats_deduped
         .iter()
-        .filter(|(new_key, _new_val)| old_stats_deduped.get::<str>(&new_key).is_some())
+        .filter(|(new_key, _new_val)| old_stats_deduped.get::<str>(new_key).is_some())
         .for_each(|(new_key, new_val)| {
-            let old_val = old_stats_deduped.get::<str>(&new_key).unwrap();
-            println!("{} {} => {}", new_key, old_val, new_val);
+            let old_val = old_stats_deduped.get::<str>(new_key).unwrap();
+            println!("{new_key} {old_val} => {new_val}");
         });
 
     // list all gone counts (key is in old status but not in new stats)
     old_stats_deduped
         .iter()
-        .filter(|(old_key, _)| new_stats_deduped.get::<&String>(&old_key).is_none())
+        .filter(|(old_key, _)| new_stats_deduped.get::<&String>(old_key).is_none())
         .filter(|(old_key, _)| lint_filter.is_empty() || lint_filter.contains(old_key))
         .for_each(|(old_key, old_value)| {
-            println!("{} {} => 0", old_key, old_value);
+            println!("{old_key} {old_value} => 0");
         });
 }
 
@@ -828,19 +828,21 @@ fn print_stats(old_stats: HashMap<String, usize>, new_stats: HashMap<&String, us
 /// This function panics if creating one of the dirs fails.
 fn create_dirs(krate_download_dir: &Path, extract_dir: &Path) {
     std::fs::create_dir("target/lintcheck/").unwrap_or_else(|err| {
-        if err.kind() != ErrorKind::AlreadyExists {
-            panic!("cannot create lintcheck target dir");
-        }
+        assert_eq!(
+            err.kind(),
+            ErrorKind::AlreadyExists,
+            "cannot create lintcheck target dir"
+        );
     });
-    std::fs::create_dir(&krate_download_dir).unwrap_or_else(|err| {
-        if err.kind() != ErrorKind::AlreadyExists {
-            panic!("cannot create crate download dir");
-        }
+    std::fs::create_dir(krate_download_dir).unwrap_or_else(|err| {
+        assert_eq!(err.kind(), ErrorKind::AlreadyExists, "cannot create crate download dir");
     });
-    std::fs::create_dir(&extract_dir).unwrap_or_else(|err| {
-        if err.kind() != ErrorKind::AlreadyExists {
-            panic!("cannot create crate extraction dir");
-        }
+    std::fs::create_dir(extract_dir).unwrap_or_else(|err| {
+        assert_eq!(
+            err.kind(),
+            ErrorKind::AlreadyExists,
+            "cannot create crate extraction dir"
+        );
     });
 }
 
@@ -863,7 +865,7 @@ fn lintcheck_test() {
         "lintcheck/test_sources.toml",
     ];
     let status = std::process::Command::new("cargo")
-        .args(&args)
+        .args(args)
         .current_dir("..") // repo root
         .status();
     //.output();
diff --git a/src/tools/clippy/lintcheck/src/recursive.rs b/src/tools/clippy/lintcheck/src/recursive.rs
index 67dcfc2b199c..49072e65192f 100644
--- a/src/tools/clippy/lintcheck/src/recursive.rs
+++ b/src/tools/clippy/lintcheck/src/recursive.rs
@@ -1,7 +1,7 @@
 //! In `--recursive` mode we set the `lintcheck` binary as the `RUSTC_WRAPPER` of `cargo check`,
-//! this allows [crate::driver] to be run for every dependency. The driver connects to
-//! [LintcheckServer] to ask if it should be skipped, and if not sends the stderr of running clippy
-//! on the crate to the server
+//! this allows [`crate::driver`] to be run for every dependency. The driver connects to
+//! [`LintcheckServer`] to ask if it should be skipped, and if not sends the stderr of running
+//! clippy on the crate to the server
 
 use crate::ClippyWarning;
 use crate::RecursiveOptions;
@@ -109,8 +109,8 @@ impl LintcheckServer {
 
         Self {
             local_addr,
-            sender,
             receiver,
+            sender,
         }
     }
 
diff --git a/src/tools/clippy/rust-toolchain b/src/tools/clippy/rust-toolchain
index 49b13cb54e71..748d8a317160 100644
--- a/src/tools/clippy/rust-toolchain
+++ b/src/tools/clippy/rust-toolchain
@@ -1,3 +1,3 @@
 [toolchain]
-channel = "nightly-2022-10-06"
+channel = "nightly-2022-10-20"
 components = ["cargo", "llvm-tools-preview", "rust-src", "rust-std", "rustc", "rustc-dev", "rustfmt"]
diff --git a/src/tools/clippy/src/docs.rs b/src/tools/clippy/src/docs.rs
index bd27bc7938f8..c033ad294a38 100644
--- a/src/tools/clippy/src/docs.rs
+++ b/src/tools/clippy/src/docs.rs
@@ -28,6 +28,7 @@ docs! {
     "approx_constant",
     "arithmetic_side_effects",
     "as_conversions",
+    "as_ptr_cast_mut",
     "as_underscore",
     "assertions_on_constants",
     "assertions_on_result_states",
@@ -60,6 +61,7 @@ docs! {
     "cast_enum_constructor",
     "cast_enum_truncation",
     "cast_lossless",
+    "cast_nan_to_int",
     "cast_possible_truncation",
     "cast_possible_wrap",
     "cast_precision_loss",
@@ -257,6 +259,7 @@ docs! {
     "manual_async_fn",
     "manual_bits",
     "manual_clamp",
+    "manual_filter",
     "manual_filter_map",
     "manual_find",
     "manual_find_map",
@@ -313,6 +316,7 @@ docs! {
     "missing_panics_doc",
     "missing_safety_doc",
     "missing_spin_loop",
+    "missing_trait_methods",
     "mistyped_literal_suffixes",
     "mixed_case_hex_literals",
     "mixed_read_write_in_expression",
@@ -391,6 +395,7 @@ docs! {
     "panic",
     "panic_in_result_fn",
     "panicking_unwrap",
+    "partial_pub_fields",
     "partialeq_ne_impl",
     "partialeq_to_none",
     "path_buf_push_overwrite",
@@ -553,6 +558,7 @@ docs! {
     "unseparated_literal_suffix",
     "unsound_collection_transmute",
     "unused_async",
+    "unused_format_specs",
     "unused_io_amount",
     "unused_peekable",
     "unused_rounding",
diff --git a/src/tools/clippy/src/docs/as_ptr_cast_mut.txt b/src/tools/clippy/src/docs/as_ptr_cast_mut.txt
new file mode 100644
index 000000000000..228dde996bb2
--- /dev/null
+++ b/src/tools/clippy/src/docs/as_ptr_cast_mut.txt
@@ -0,0 +1,19 @@
+### What it does
+Checks for the result of a `&self`-taking `as_ptr` being cast to a mutable pointer
+
+### Why is this bad?
+Since `as_ptr` takes a `&self`, the pointer won't have write permissions unless interior
+mutability is used, making it unlikely that having it as a mutable pointer is correct.
+
+### Example
+```
+let string = String::with_capacity(1);
+let ptr = string.as_ptr() as *mut u8;
+unsafe { ptr.write(4) }; // UNDEFINED BEHAVIOUR
+```
+Use instead:
+```
+let mut string = String::with_capacity(1);
+let ptr = string.as_mut_ptr();
+unsafe { ptr.write(4) };
+```
\ No newline at end of file
diff --git a/src/tools/clippy/src/docs/box_default.txt b/src/tools/clippy/src/docs/box_default.txt
index ffac894d0c50..1c670c773337 100644
--- a/src/tools/clippy/src/docs/box_default.txt
+++ b/src/tools/clippy/src/docs/box_default.txt
@@ -7,12 +7,6 @@ First, it's more complex, involving two calls instead of one.
 Second, `Box::default()` can be faster
 [in certain cases](https://nnethercote.github.io/perf-book/standard-library-types.html#box).
 
-### Known problems
-The lint may miss some cases (e.g. Box::new(String::from(""))).
-On the other hand, it will trigger on cases where the `default`
-code comes from a macro that does something different based on
-e.g. target operating system.
-
 ### Example
 ```
 let x: Box<String> = Box::new(Default::default());
diff --git a/src/tools/clippy/src/docs/cast_nan_to_int.txt b/src/tools/clippy/src/docs/cast_nan_to_int.txt
new file mode 100644
index 000000000000..122f5da0c921
--- /dev/null
+++ b/src/tools/clippy/src/docs/cast_nan_to_int.txt
@@ -0,0 +1,15 @@
+### What it does
+Checks for a known NaN float being cast to an integer
+
+### Why is this bad?
+NaNs are cast into zero, so one could simply use this and make the
+code more readable. The lint could also hint at a programmer error.
+
+### Example
+```
+let _: (0.0_f32 / 0.0) as u64;
+```
+Use instead:
+```
+let _: = 0_u64;
+```
\ No newline at end of file
diff --git a/src/tools/clippy/src/docs/manual_filter.txt b/src/tools/clippy/src/docs/manual_filter.txt
new file mode 100644
index 000000000000..19a4d9319d94
--- /dev/null
+++ b/src/tools/clippy/src/docs/manual_filter.txt
@@ -0,0 +1,21 @@
+### What it does
+Checks for usages of `match` which could be implemented using `filter`
+
+### Why is this bad?
+Using the `filter` method is clearer and more concise.
+
+### Example
+```
+match Some(0) {
+    Some(x) => if x % 2 == 0 {
+                    Some(x)
+               } else {
+                    None
+                },
+    None => None,
+};
+```
+Use instead:
+```
+Some(0).filter(|&x| x % 2 == 0);
+```
\ No newline at end of file
diff --git a/src/tools/clippy/src/docs/missing_trait_methods.txt b/src/tools/clippy/src/docs/missing_trait_methods.txt
new file mode 100644
index 000000000000..788ad764f8c3
--- /dev/null
+++ b/src/tools/clippy/src/docs/missing_trait_methods.txt
@@ -0,0 +1,40 @@
+### What it does
+Checks if a provided method is used implicitly by a trait
+implementation. A usage example would be a wrapper where every method
+should perform some operation before delegating to the inner type's
+implemenation.
+
+This lint should typically be enabled on a specific trait `impl` item
+rather than globally.
+
+### Why is this bad?
+Indicates that a method is missing.
+
+### Example
+```
+trait Trait {
+    fn required();
+
+    fn provided() {}
+}
+
+#[warn(clippy::missing_trait_methods)]
+impl Trait for Type {
+    fn required() { /* ... */ }
+}
+```
+Use instead:
+```
+trait Trait {
+    fn required();
+
+    fn provided() {}
+}
+
+#[warn(clippy::missing_trait_methods)]
+impl Trait for Type {
+    fn required() { /* ... */ }
+
+    fn provided() { /* ... */ }
+}
+```
\ No newline at end of file
diff --git a/src/tools/clippy/src/docs/partial_pub_fields.txt b/src/tools/clippy/src/docs/partial_pub_fields.txt
new file mode 100644
index 000000000000..b529adf1547d
--- /dev/null
+++ b/src/tools/clippy/src/docs/partial_pub_fields.txt
@@ -0,0 +1,27 @@
+### What it does
+Checks whether partial fields of a struct are public.
+
+Either make all fields of a type public, or make none of them public
+
+### Why is this bad?
+Most types should either be:
+* Abstract data types: complex objects with opaque implementation which guard
+interior invariants and expose intentionally limited API to the outside world.
+* Data: relatively simple objects which group a bunch of related attributes together.
+
+### Example
+```
+pub struct Color {
+    pub r: u8,
+    pub g: u8,
+    b: u8,
+}
+```
+Use instead:
+```
+pub struct Color {
+    pub r: u8,
+    pub g: u8,
+    pub b: u8,
+}
+```
\ No newline at end of file
diff --git a/src/tools/clippy/src/docs/unused_format_specs.txt b/src/tools/clippy/src/docs/unused_format_specs.txt
new file mode 100644
index 000000000000..77be3a2fb170
--- /dev/null
+++ b/src/tools/clippy/src/docs/unused_format_specs.txt
@@ -0,0 +1,24 @@
+### What it does
+Detects [formatting parameters] that have no effect on the output of
+`format!()`, `println!()` or similar macros.
+
+### Why is this bad?
+Shorter format specifiers are easier to read, it may also indicate that
+an expected formatting operation such as adding padding isn't happening.
+
+### Example
+```
+println!("{:.}", 1.0);
+
+println!("not padded: {:5}", format_args!("..."));
+```
+Use instead:
+```
+println!("{}", 1.0);
+
+println!("not padded: {}", format_args!("..."));
+// OR
+println!("padded: {:5}", format!("..."));
+```
+
+[formatting parameters]: https://doc.rust-lang.org/std/fmt/index.html#formatting-parameters
\ No newline at end of file
diff --git a/src/tools/clippy/src/driver.rs b/src/tools/clippy/src/driver.rs
index b12208ac62a8..f24d3507823e 100644
--- a/src/tools/clippy/src/driver.rs
+++ b/src/tools/clippy/src/driver.rs
@@ -23,8 +23,8 @@ use std::borrow::Cow;
 use std::env;
 use std::ops::Deref;
 use std::panic;
-use std::path::{Path, PathBuf};
-use std::process::{exit, Command};
+use std::path::Path;
+use std::process::exit;
 use std::sync::LazyLock;
 
 /// If a command-line option matches `find_arg`, then apply the predicate `pred` on its value. If
@@ -179,6 +179,7 @@ fn report_clippy_ice(info: &panic::PanicInfo<'_>, bug_report_url: &str) {
         false,
         None,
         false,
+        false,
     ));
     let handler = rustc_errors::Handler::with_emitter(true, None, emitter);
 
@@ -209,17 +210,6 @@ fn report_clippy_ice(info: &panic::PanicInfo<'_>, bug_report_url: &str) {
     interface::try_print_query_stack(&handler, num_frames);
 }
 
-fn toolchain_path(home: Option<String>, toolchain: Option<String>) -> Option<PathBuf> {
-    home.and_then(|home| {
-        toolchain.map(|toolchain| {
-            let mut path = PathBuf::from(home);
-            path.push("toolchains");
-            path.push(toolchain);
-            path
-        })
-    })
-}
-
 #[allow(clippy::too_many_lines)]
 pub fn main() {
     rustc_driver::init_rustc_env_logger();
@@ -227,51 +217,6 @@ pub fn main() {
     exit(rustc_driver::catch_with_exit_code(move || {
         let mut orig_args: Vec<String> = env::args().collect();
 
-        // Get the sysroot, looking from most specific to this invocation to the least:
-        // - command line
-        // - runtime environment
-        //    - SYSROOT
-        //    - RUSTUP_HOME, MULTIRUST_HOME, RUSTUP_TOOLCHAIN, MULTIRUST_TOOLCHAIN
-        // - sysroot from rustc in the path
-        // - compile-time environment
-        //    - SYSROOT
-        //    - RUSTUP_HOME, MULTIRUST_HOME, RUSTUP_TOOLCHAIN, MULTIRUST_TOOLCHAIN
-        let sys_root_arg = arg_value(&orig_args, "--sysroot", |_| true);
-        let have_sys_root_arg = sys_root_arg.is_some();
-        let sys_root = sys_root_arg
-            .map(PathBuf::from)
-            .or_else(|| std::env::var("SYSROOT").ok().map(PathBuf::from))
-            .or_else(|| {
-                let home = std::env::var("RUSTUP_HOME")
-                    .or_else(|_| std::env::var("MULTIRUST_HOME"))
-                    .ok();
-                let toolchain = std::env::var("RUSTUP_TOOLCHAIN")
-                    .or_else(|_| std::env::var("MULTIRUST_TOOLCHAIN"))
-                    .ok();
-                toolchain_path(home, toolchain)
-            })
-            .or_else(|| {
-                Command::new("rustc")
-                    .arg("--print")
-                    .arg("sysroot")
-                    .output()
-                    .ok()
-                    .and_then(|out| String::from_utf8(out.stdout).ok())
-                    .map(|s| PathBuf::from(s.trim()))
-            })
-            .or_else(|| option_env!("SYSROOT").map(PathBuf::from))
-            .or_else(|| {
-                let home = option_env!("RUSTUP_HOME")
-                    .or(option_env!("MULTIRUST_HOME"))
-                    .map(ToString::to_string);
-                let toolchain = option_env!("RUSTUP_TOOLCHAIN")
-                    .or(option_env!("MULTIRUST_TOOLCHAIN"))
-                    .map(ToString::to_string);
-                toolchain_path(home, toolchain)
-            })
-            .map(|pb| pb.to_string_lossy().to_string())
-            .expect("need to specify SYSROOT env var during clippy compilation, or use rustup or multirust");
-
         // make "clippy-driver --rustc" work like a subcommand that passes further args to "rustc"
         // for example `clippy-driver --rustc --version` will print the rustc version that clippy-driver
         // uses
@@ -279,13 +224,7 @@ pub fn main() {
             orig_args.remove(pos);
             orig_args[0] = "rustc".to_string();
 
-            // if we call "rustc", we need to pass --sysroot here as well
-            let mut args: Vec<String> = orig_args.clone();
-            if !have_sys_root_arg {
-                args.extend(vec!["--sysroot".into(), sys_root]);
-            };
-
-            return rustc_driver::RunCompiler::new(&args, &mut DefaultCallbacks).run();
+            return rustc_driver::RunCompiler::new(&orig_args, &mut DefaultCallbacks).run();
         }
 
         if orig_args.iter().any(|a| a == "--version" || a == "-V") {
@@ -308,14 +247,6 @@ pub fn main() {
             exit(0);
         }
 
-        // this conditional check for the --sysroot flag is there so users can call
-        // `clippy_driver` directly
-        // without having to pass --sysroot or anything
-        let mut args: Vec<String> = orig_args.clone();
-        if !have_sys_root_arg {
-            args.extend(vec!["--sysroot".into(), sys_root]);
-        };
-
         let mut no_deps = false;
         let clippy_args_var = env::var("CLIPPY_ARGS").ok();
         let clippy_args = clippy_args_var
@@ -344,10 +275,11 @@ pub fn main() {
 
         let clippy_enabled = !cap_lints_allow && (!no_deps || in_primary_package);
         if clippy_enabled {
+            let mut args: Vec<String> = orig_args.clone();
             args.extend(clippy_args);
             rustc_driver::RunCompiler::new(&args, &mut ClippyCallbacks { clippy_args_var }).run()
         } else {
-            rustc_driver::RunCompiler::new(&args, &mut RustcCallbacks { clippy_args_var }).run()
+            rustc_driver::RunCompiler::new(&orig_args, &mut RustcCallbacks { clippy_args_var }).run()
         }
     }))
 }
diff --git a/src/tools/clippy/tests/compile-test.rs b/src/tools/clippy/tests/compile-test.rs
index fa769222d1af..c10ee969c014 100644
--- a/src/tools/clippy/tests/compile-test.rs
+++ b/src/tools/clippy/tests/compile-test.rs
@@ -283,7 +283,7 @@ fn run_ui_cargo() {
                 env::set_current_dir(&src_path)?;
 
                 let cargo_toml_path = case.path().join("Cargo.toml");
-                let cargo_content = fs::read(&cargo_toml_path)?;
+                let cargo_content = fs::read(cargo_toml_path)?;
                 let cargo_parsed: toml::Value = toml::from_str(
                     std::str::from_utf8(&cargo_content).expect("`Cargo.toml` is not a valid utf-8 file!"),
                 )
diff --git a/src/tools/clippy/tests/dogfood.rs b/src/tools/clippy/tests/dogfood.rs
index 961525bbd910..6d0022f7a5cc 100644
--- a/src/tools/clippy/tests/dogfood.rs
+++ b/src/tools/clippy/tests/dogfood.rs
@@ -20,7 +20,14 @@ fn dogfood_clippy() {
     }
 
     // "" is the root package
-    for package in &["", "clippy_dev", "clippy_lints", "clippy_utils", "rustc_tools_util"] {
+    for package in &[
+        "",
+        "clippy_dev",
+        "clippy_lints",
+        "clippy_utils",
+        "lintcheck",
+        "rustc_tools_util",
+    ] {
         run_clippy_for_package(package, &["-D", "clippy::all", "-D", "clippy::pedantic"]);
     }
 }
diff --git a/src/tools/clippy/tests/ui-internal/custom_ice_message.stderr b/src/tools/clippy/tests/ui-internal/custom_ice_message.stderr
index a1b8e2ee162c..07c5941013c1 100644
--- a/src/tools/clippy/tests/ui-internal/custom_ice_message.stderr
+++ b/src/tools/clippy/tests/ui-internal/custom_ice_message.stderr
@@ -1,4 +1,4 @@
-thread 'rustc' panicked at 'Would you like some help with that?', clippy_lints/src/utils/internal_lints.rs
+thread 'rustc' panicked at 'Would you like some help with that?', clippy_lints/src/utils/internal_lints/produce_ice.rs:28:9
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 
 error: internal compiler error: unexpected panic
diff --git a/src/tools/clippy/tests/ui-internal/invalid_paths.rs b/src/tools/clippy/tests/ui-internal/invalid_paths.rs
index b823ff7fe37f..9a9790a4bae5 100644
--- a/src/tools/clippy/tests/ui-internal/invalid_paths.rs
+++ b/src/tools/clippy/tests/ui-internal/invalid_paths.rs
@@ -1,5 +1,5 @@
 #![warn(clippy::internal)]
-#![allow(clippy::missing_clippy_version_attribute)]
+#![allow(clippy::missing_clippy_version_attribute, clippy::unnecessary_def_path)]
 
 mod paths {
     // Good path
diff --git a/src/tools/clippy/tests/ui-internal/unnecessary_def_path.fixed b/src/tools/clippy/tests/ui-internal/unnecessary_def_path.fixed
index 4c050332f2cc..cbbb46523064 100644
--- a/src/tools/clippy/tests/ui-internal/unnecessary_def_path.fixed
+++ b/src/tools/clippy/tests/ui-internal/unnecessary_def_path.fixed
@@ -28,9 +28,9 @@ use rustc_hir::Expr;
 use rustc_lint::LateContext;
 use rustc_middle::ty::Ty;
 
-#[allow(unused)]
+#[allow(unused, clippy::unnecessary_def_path)]
 static OPTION: [&str; 3] = ["core", "option", "Option"];
-#[allow(unused)]
+#[allow(unused, clippy::unnecessary_def_path)]
 const RESULT: &[&str] = &["core", "result", "Result"];
 
 fn _f<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>, did: DefId, expr: &Expr<'_>) {
@@ -38,7 +38,7 @@ fn _f<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>, did: DefId, expr: &Expr<'_>) {
     let _ = is_type_diagnostic_item(cx, ty, sym::Result);
     let _ = is_type_diagnostic_item(cx, ty, sym::Result);
 
-    #[allow(unused)]
+    #[allow(unused, clippy::unnecessary_def_path)]
     let rc_path = &["alloc", "rc", "Rc"];
     let _ = is_type_diagnostic_item(cx, ty, sym::Rc);
 
diff --git a/src/tools/clippy/tests/ui-internal/unnecessary_def_path.rs b/src/tools/clippy/tests/ui-internal/unnecessary_def_path.rs
index 6506f1f164ac..f17fed6c6530 100644
--- a/src/tools/clippy/tests/ui-internal/unnecessary_def_path.rs
+++ b/src/tools/clippy/tests/ui-internal/unnecessary_def_path.rs
@@ -28,9 +28,9 @@ use rustc_hir::Expr;
 use rustc_lint::LateContext;
 use rustc_middle::ty::Ty;
 
-#[allow(unused)]
+#[allow(unused, clippy::unnecessary_def_path)]
 static OPTION: [&str; 3] = ["core", "option", "Option"];
-#[allow(unused)]
+#[allow(unused, clippy::unnecessary_def_path)]
 const RESULT: &[&str] = &["core", "result", "Result"];
 
 fn _f<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>, did: DefId, expr: &Expr<'_>) {
@@ -38,7 +38,7 @@ fn _f<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>, did: DefId, expr: &Expr<'_>) {
     let _ = match_type(cx, ty, RESULT);
     let _ = match_type(cx, ty, &["core", "result", "Result"]);
 
-    #[allow(unused)]
+    #[allow(unused, clippy::unnecessary_def_path)]
     let rc_path = &["alloc", "rc", "Rc"];
     let _ = clippy_utils::ty::match_type(cx, ty, rc_path);
 
diff --git a/src/tools/clippy/tests/ui-internal/unnecessary_def_path_hardcoded_path.rs b/src/tools/clippy/tests/ui-internal/unnecessary_def_path_hardcoded_path.rs
new file mode 100644
index 000000000000..b5ff3a542056
--- /dev/null
+++ b/src/tools/clippy/tests/ui-internal/unnecessary_def_path_hardcoded_path.rs
@@ -0,0 +1,16 @@
+#![feature(rustc_private)]
+#![allow(unused)]
+#![warn(clippy::unnecessary_def_path)]
+
+extern crate rustc_hir;
+
+use rustc_hir::LangItem;
+
+fn main() {
+    const DEREF_TRAIT: [&str; 4] = ["core", "ops", "deref", "Deref"];
+    const DEREF_MUT_TRAIT: [&str; 4] = ["core", "ops", "deref", "DerefMut"];
+    const DEREF_TRAIT_METHOD: [&str; 5] = ["core", "ops", "deref", "Deref", "deref"];
+
+    // Don't lint, not yet a diagnostic or language item
+    const DEREF_MUT_TRAIT_METHOD: [&str; 5] = ["core", "ops", "deref", "DerefMut", "deref_mut"];
+}
diff --git a/src/tools/clippy/tests/ui-internal/unnecessary_def_path_hardcoded_path.stderr b/src/tools/clippy/tests/ui-internal/unnecessary_def_path_hardcoded_path.stderr
new file mode 100644
index 000000000000..af46d87bf676
--- /dev/null
+++ b/src/tools/clippy/tests/ui-internal/unnecessary_def_path_hardcoded_path.stderr
@@ -0,0 +1,27 @@
+error: hardcoded path to a language item
+  --> $DIR/unnecessary_def_path_hardcoded_path.rs:11:40
+   |
+LL |     const DEREF_MUT_TRAIT: [&str; 4] = ["core", "ops", "deref", "DerefMut"];
+   |                                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = help: convert all references to use `LangItem::DerefMut`
+   = note: `-D clippy::unnecessary-def-path` implied by `-D warnings`
+
+error: hardcoded path to a diagnostic item
+  --> $DIR/unnecessary_def_path_hardcoded_path.rs:12:43
+   |
+LL |     const DEREF_TRAIT_METHOD: [&str; 5] = ["core", "ops", "deref", "Deref", "deref"];
+   |                                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = help: convert all references to use `sym::deref_method`
+
+error: hardcoded path to a diagnostic item
+  --> $DIR/unnecessary_def_path_hardcoded_path.rs:10:36
+   |
+LL |     const DEREF_TRAIT: [&str; 4] = ["core", "ops", "deref", "Deref"];
+   |                                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = help: convert all references to use `sym::Deref`
+
+error: aborting due to 3 previous errors
+
diff --git a/src/tools/clippy/tests/ui/as_ptr_cast_mut.rs b/src/tools/clippy/tests/ui/as_ptr_cast_mut.rs
new file mode 100644
index 000000000000..0d1d9258433b
--- /dev/null
+++ b/src/tools/clippy/tests/ui/as_ptr_cast_mut.rs
@@ -0,0 +1,37 @@
+#![allow(unused)]
+#![warn(clippy::as_ptr_cast_mut)]
+#![allow(clippy::wrong_self_convention)]
+
+struct MutPtrWrapper(Vec<u8>);
+impl MutPtrWrapper {
+    fn as_ptr(&mut self) -> *const u8 {
+        self.0.as_mut_ptr() as *const u8
+    }
+}
+
+struct Covariant<T>(*const T);
+impl<T> Covariant<T> {
+    fn as_ptr(self) -> *const T {
+        self.0
+    }
+}
+
+fn main() {
+    let mut string = String::new();
+    let _ = string.as_ptr() as *mut u8;
+    let _: *mut i8 = string.as_ptr() as *mut _;
+    let _ = string.as_ptr() as *const i8;
+    let _ = string.as_mut_ptr();
+    let _ = string.as_mut_ptr() as *mut u8;
+    let _ = string.as_mut_ptr() as *const u8;
+
+    let nn = std::ptr::NonNull::new(4 as *mut u8).unwrap();
+    let _ = nn.as_ptr() as *mut u8;
+
+    let mut wrap = MutPtrWrapper(Vec::new());
+    let _ = wrap.as_ptr() as *mut u8;
+
+    let mut local = 4;
+    let ref_with_write_perm = Covariant(std::ptr::addr_of_mut!(local) as *const _);
+    let _ = ref_with_write_perm.as_ptr() as *mut u8;
+}
diff --git a/src/tools/clippy/tests/ui/as_ptr_cast_mut.stderr b/src/tools/clippy/tests/ui/as_ptr_cast_mut.stderr
new file mode 100644
index 000000000000..2189c3d2f855
--- /dev/null
+++ b/src/tools/clippy/tests/ui/as_ptr_cast_mut.stderr
@@ -0,0 +1,16 @@
+error: casting the result of `as_ptr` to *mut u8
+  --> $DIR/as_ptr_cast_mut.rs:21:13
+   |
+LL |     let _ = string.as_ptr() as *mut u8;
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace with: `string.as_mut_ptr()`
+   |
+   = note: `-D clippy::as-ptr-cast-mut` implied by `-D warnings`
+
+error: casting the result of `as_ptr` to *mut i8
+  --> $DIR/as_ptr_cast_mut.rs:22:22
+   |
+LL |     let _: *mut i8 = string.as_ptr() as *mut _;
+   |                      ^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace with: `string.as_mut_ptr()`
+
+error: aborting due to 2 previous errors
+
diff --git a/src/tools/clippy/tests/ui/author.stdout b/src/tools/clippy/tests/ui/author.stdout
index 597318a556b8..27ad538f24d8 100644
--- a/src/tools/clippy/tests/ui/author.stdout
+++ b/src/tools/clippy/tests/ui/author.stdout
@@ -1,14 +1,12 @@
-if_chain! {
-    if let StmtKind::Local(local) = stmt.kind;
-    if let Some(init) = local.init;
-    if let ExprKind::Cast(expr, cast_ty) = init.kind;
-    if let TyKind::Path(ref qpath) = cast_ty.kind;
-    if match_qpath(qpath, &["char"]);
-    if let ExprKind::Lit(ref lit) = expr.kind;
-    if let LitKind::Int(69, LitIntType::Unsuffixed) = lit.node;
-    if let PatKind::Binding(BindingAnnotation::NONE, _, name, None) = local.pat.kind;
-    if name.as_str() == "x";
-    then {
-        // report your lint here
-    }
+if let StmtKind::Local(local) = stmt.kind
+    && let Some(init) = local.init
+    && let ExprKind::Cast(expr, cast_ty) = init.kind
+    && let TyKind::Path(ref qpath) = cast_ty.kind
+    && match_qpath(qpath, &["char"])
+    && let ExprKind::Lit(ref lit) = expr.kind
+    && let LitKind::Int(69, LitIntType::Unsuffixed) = lit.node
+    && let PatKind::Binding(BindingAnnotation::NONE, _, name, None) = local.pat.kind
+    && name.as_str() == "x"
+{
+    // report your lint here
 }
diff --git a/src/tools/clippy/tests/ui/author/blocks.stdout b/src/tools/clippy/tests/ui/author/blocks.stdout
index a529981e2e68..9de0550d81d0 100644
--- a/src/tools/clippy/tests/ui/author/blocks.stdout
+++ b/src/tools/clippy/tests/ui/author/blocks.stdout
@@ -1,64 +1,58 @@
-if_chain! {
-    if let ExprKind::Block(block, None) = expr.kind;
-    if block.stmts.len() == 3;
-    if let StmtKind::Local(local) = block.stmts[0].kind;
-    if let Some(init) = local.init;
-    if let ExprKind::Lit(ref lit) = init.kind;
-    if let LitKind::Int(42, LitIntType::Signed(IntTy::I32)) = lit.node;
-    if let PatKind::Binding(BindingAnnotation::NONE, _, name, None) = local.pat.kind;
-    if name.as_str() == "x";
-    if let StmtKind::Local(local1) = block.stmts[1].kind;
-    if let Some(init1) = local1.init;
-    if let ExprKind::Lit(ref lit1) = init1.kind;
-    if let LitKind::Float(_, LitFloatType::Suffixed(FloatTy::F32)) = lit1.node;
-    if let PatKind::Binding(BindingAnnotation::NONE, _, name1, None) = local1.pat.kind;
-    if name1.as_str() == "_t";
-    if let StmtKind::Semi(e) = block.stmts[2].kind;
-    if let ExprKind::Unary(UnOp::Neg, inner) = e.kind;
-    if let ExprKind::Path(ref qpath) = inner.kind;
-    if match_qpath(qpath, &["x"]);
-    if block.expr.is_none();
-    then {
-        // report your lint here
-    }
+if let ExprKind::Block(block, None) = expr.kind
+    && block.stmts.len() == 3
+    && let StmtKind::Local(local) = block.stmts[0].kind
+    && let Some(init) = local.init
+    && let ExprKind::Lit(ref lit) = init.kind
+    && let LitKind::Int(42, LitIntType::Signed(IntTy::I32)) = lit.node
+    && let PatKind::Binding(BindingAnnotation::NONE, _, name, None) = local.pat.kind
+    && name.as_str() == "x"
+    && let StmtKind::Local(local1) = block.stmts[1].kind
+    && let Some(init1) = local1.init
+    && let ExprKind::Lit(ref lit1) = init1.kind
+    && let LitKind::Float(_, LitFloatType::Suffixed(FloatTy::F32)) = lit1.node
+    && let PatKind::Binding(BindingAnnotation::NONE, _, name1, None) = local1.pat.kind
+    && name1.as_str() == "_t"
+    && let StmtKind::Semi(e) = block.stmts[2].kind
+    && let ExprKind::Unary(UnOp::Neg, inner) = e.kind
+    && let ExprKind::Path(ref qpath) = inner.kind
+    && match_qpath(qpath, &["x"])
+    && block.expr.is_none()
+{
+    // report your lint here
 }
-if_chain! {
-    if let ExprKind::Block(block, None) = expr.kind;
-    if block.stmts.len() == 1;
-    if let StmtKind::Local(local) = block.stmts[0].kind;
-    if let Some(init) = local.init;
-    if let ExprKind::Call(func, args) = init.kind;
-    if let ExprKind::Path(ref qpath) = func.kind;
-    if match_qpath(qpath, &["String", "new"]);
-    if args.is_empty();
-    if let PatKind::Binding(BindingAnnotation::NONE, _, name, None) = local.pat.kind;
-    if name.as_str() == "expr";
-    if let Some(trailing_expr) = block.expr;
-    if let ExprKind::Call(func1, args1) = trailing_expr.kind;
-    if let ExprKind::Path(ref qpath1) = func1.kind;
-    if match_qpath(qpath1, &["drop"]);
-    if args1.len() == 1;
-    if let ExprKind::Path(ref qpath2) = args1[0].kind;
-    if match_qpath(qpath2, &["expr"]);
-    then {
-        // report your lint here
-    }
+if let ExprKind::Block(block, None) = expr.kind
+    && block.stmts.len() == 1
+    && let StmtKind::Local(local) = block.stmts[0].kind
+    && let Some(init) = local.init
+    && let ExprKind::Call(func, args) = init.kind
+    && let ExprKind::Path(ref qpath) = func.kind
+    && match_qpath(qpath, &["String", "new"])
+    && args.is_empty()
+    && let PatKind::Binding(BindingAnnotation::NONE, _, name, None) = local.pat.kind
+    && name.as_str() == "expr"
+    && let Some(trailing_expr) = block.expr
+    && let ExprKind::Call(func1, args1) = trailing_expr.kind
+    && let ExprKind::Path(ref qpath1) = func1.kind
+    && match_qpath(qpath1, &["drop"])
+    && args1.len() == 1
+    && let ExprKind::Path(ref qpath2) = args1[0].kind
+    && match_qpath(qpath2, &["expr"])
+{
+    // report your lint here
 }
-if_chain! {
-    if let ExprKind::Closure(CaptureBy::Value, fn_decl, body_id, _, None) = expr.kind;
-    if let FnRetTy::DefaultReturn(_) = fn_decl.output;
-    let expr1 = &cx.tcx.hir().body(body_id).value;
-    if let ExprKind::Call(func, args) = expr1.kind;
-    if let ExprKind::Path(ref qpath) = func.kind;
-    if matches!(qpath, QPath::LangItem(LangItem::FromGenerator, _));
-    if args.len() == 1;
-    if let ExprKind::Closure(CaptureBy::Value, fn_decl1, body_id1, _, Some(Movability::Static)) = args[0].kind;
-    if let FnRetTy::DefaultReturn(_) = fn_decl1.output;
-    let expr2 = &cx.tcx.hir().body(body_id1).value;
-    if let ExprKind::Block(block, None) = expr2.kind;
-    if block.stmts.is_empty();
-    if block.expr.is_none();
-    then {
-        // report your lint here
-    }
+if let ExprKind::Closure(CaptureBy::Value, fn_decl, body_id, _, None) = expr.kind
+    && let FnRetTy::DefaultReturn(_) = fn_decl.output
+    && expr1 = &cx.tcx.hir().body(body_id).value
+    && let ExprKind::Call(func, args) = expr1.kind
+    && let ExprKind::Path(ref qpath) = func.kind
+    && matches!(qpath, QPath::LangItem(LangItem::FromGenerator, _))
+    && args.len() == 1
+    && let ExprKind::Closure(CaptureBy::Value, fn_decl1, body_id1, _, Some(Movability::Static)) = args[0].kind
+    && let FnRetTy::DefaultReturn(_) = fn_decl1.output
+    && expr2 = &cx.tcx.hir().body(body_id1).value
+    && let ExprKind::Block(block, None) = expr2.kind
+    && block.stmts.is_empty()
+    && block.expr.is_none()
+{
+    // report your lint here
 }
diff --git a/src/tools/clippy/tests/ui/author/call.stdout b/src/tools/clippy/tests/ui/author/call.stdout
index 266312d63e50..f040f6330a64 100644
--- a/src/tools/clippy/tests/ui/author/call.stdout
+++ b/src/tools/clippy/tests/ui/author/call.stdout
@@ -1,16 +1,14 @@
-if_chain! {
-    if let StmtKind::Local(local) = stmt.kind;
-    if let Some(init) = local.init;
-    if let ExprKind::Call(func, args) = init.kind;
-    if let ExprKind::Path(ref qpath) = func.kind;
-    if match_qpath(qpath, &["{{root}}", "std", "cmp", "min"]);
-    if args.len() == 2;
-    if let ExprKind::Lit(ref lit) = args[0].kind;
-    if let LitKind::Int(3, LitIntType::Unsuffixed) = lit.node;
-    if let ExprKind::Lit(ref lit1) = args[1].kind;
-    if let LitKind::Int(4, LitIntType::Unsuffixed) = lit1.node;
-    if let PatKind::Wild = local.pat.kind;
-    then {
-        // report your lint here
-    }
+if let StmtKind::Local(local) = stmt.kind
+    && let Some(init) = local.init
+    && let ExprKind::Call(func, args) = init.kind
+    && let ExprKind::Path(ref qpath) = func.kind
+    && match_qpath(qpath, &["{{root}}", "std", "cmp", "min"])
+    && args.len() == 2
+    && let ExprKind::Lit(ref lit) = args[0].kind
+    && let LitKind::Int(3, LitIntType::Unsuffixed) = lit.node
+    && let ExprKind::Lit(ref lit1) = args[1].kind
+    && let LitKind::Int(4, LitIntType::Unsuffixed) = lit1.node
+    && let PatKind::Wild = local.pat.kind
+{
+    // report your lint here
 }
diff --git a/src/tools/clippy/tests/ui/author/if.stdout b/src/tools/clippy/tests/ui/author/if.stdout
index 8d92849b3668..5d79618820d8 100644
--- a/src/tools/clippy/tests/ui/author/if.stdout
+++ b/src/tools/clippy/tests/ui/author/if.stdout
@@ -1,50 +1,46 @@
-if_chain! {
-    if let StmtKind::Local(local) = stmt.kind;
-    if let Some(init) = local.init;
-    if let ExprKind::If(cond, then, Some(else_expr)) = init.kind;
-    if let ExprKind::DropTemps(expr) = cond.kind;
-    if let ExprKind::Lit(ref lit) = expr.kind;
-    if let LitKind::Bool(true) = lit.node;
-    if let ExprKind::Block(block, None) = then.kind;
-    if block.stmts.len() == 1;
-    if let StmtKind::Semi(e) = block.stmts[0].kind;
-    if let ExprKind::Binary(op, left, right) = e.kind;
-    if BinOpKind::Eq == op.node;
-    if let ExprKind::Lit(ref lit1) = left.kind;
-    if let LitKind::Int(1, LitIntType::Unsuffixed) = lit1.node;
-    if let ExprKind::Lit(ref lit2) = right.kind;
-    if let LitKind::Int(1, LitIntType::Unsuffixed) = lit2.node;
-    if block.expr.is_none();
-    if let ExprKind::Block(block1, None) = else_expr.kind;
-    if block1.stmts.len() == 1;
-    if let StmtKind::Semi(e1) = block1.stmts[0].kind;
-    if let ExprKind::Binary(op1, left1, right1) = e1.kind;
-    if BinOpKind::Eq == op1.node;
-    if let ExprKind::Lit(ref lit3) = left1.kind;
-    if let LitKind::Int(2, LitIntType::Unsuffixed) = lit3.node;
-    if let ExprKind::Lit(ref lit4) = right1.kind;
-    if let LitKind::Int(2, LitIntType::Unsuffixed) = lit4.node;
-    if block1.expr.is_none();
-    if let PatKind::Wild = local.pat.kind;
-    then {
-        // report your lint here
-    }
+if let StmtKind::Local(local) = stmt.kind
+    && let Some(init) = local.init
+    && let ExprKind::If(cond, then, Some(else_expr)) = init.kind
+    && let ExprKind::DropTemps(expr) = cond.kind
+    && let ExprKind::Lit(ref lit) = expr.kind
+    && let LitKind::Bool(true) = lit.node
+    && let ExprKind::Block(block, None) = then.kind
+    && block.stmts.len() == 1
+    && let StmtKind::Semi(e) = block.stmts[0].kind
+    && let ExprKind::Binary(op, left, right) = e.kind
+    && BinOpKind::Eq == op.node
+    && let ExprKind::Lit(ref lit1) = left.kind
+    && let LitKind::Int(1, LitIntType::Unsuffixed) = lit1.node
+    && let ExprKind::Lit(ref lit2) = right.kind
+    && let LitKind::Int(1, LitIntType::Unsuffixed) = lit2.node
+    && block.expr.is_none()
+    && let ExprKind::Block(block1, None) = else_expr.kind
+    && block1.stmts.len() == 1
+    && let StmtKind::Semi(e1) = block1.stmts[0].kind
+    && let ExprKind::Binary(op1, left1, right1) = e1.kind
+    && BinOpKind::Eq == op1.node
+    && let ExprKind::Lit(ref lit3) = left1.kind
+    && let LitKind::Int(2, LitIntType::Unsuffixed) = lit3.node
+    && let ExprKind::Lit(ref lit4) = right1.kind
+    && let LitKind::Int(2, LitIntType::Unsuffixed) = lit4.node
+    && block1.expr.is_none()
+    && let PatKind::Wild = local.pat.kind
+{
+    // report your lint here
 }
-if_chain! {
-    if let ExprKind::If(cond, then, Some(else_expr)) = expr.kind;
-    if let ExprKind::Let(let_expr) = cond.kind;
-    if let PatKind::Lit(lit_expr) = let_expr.pat.kind;
-    if let ExprKind::Lit(ref lit) = lit_expr.kind;
-    if let LitKind::Bool(true) = lit.node;
-    if let ExprKind::Path(ref qpath) = let_expr.init.kind;
-    if match_qpath(qpath, &["a"]);
-    if let ExprKind::Block(block, None) = then.kind;
-    if block.stmts.is_empty();
-    if block.expr.is_none();
-    if let ExprKind::Block(block1, None) = else_expr.kind;
-    if block1.stmts.is_empty();
-    if block1.expr.is_none();
-    then {
-        // report your lint here
-    }
+if let ExprKind::If(cond, then, Some(else_expr)) = expr.kind
+    && let ExprKind::Let(let_expr) = cond.kind
+    && let PatKind::Lit(lit_expr) = let_expr.pat.kind
+    && let ExprKind::Lit(ref lit) = lit_expr.kind
+    && let LitKind::Bool(true) = lit.node
+    && let ExprKind::Path(ref qpath) = let_expr.init.kind
+    && match_qpath(qpath, &["a"])
+    && let ExprKind::Block(block, None) = then.kind
+    && block.stmts.is_empty()
+    && block.expr.is_none()
+    && let ExprKind::Block(block1, None) = else_expr.kind
+    && block1.stmts.is_empty()
+    && block1.expr.is_none()
+{
+    // report your lint here
 }
diff --git a/src/tools/clippy/tests/ui/author/issue_3849.stdout b/src/tools/clippy/tests/ui/author/issue_3849.stdout
index bce4bc702733..32a3127b85a3 100644
--- a/src/tools/clippy/tests/ui/author/issue_3849.stdout
+++ b/src/tools/clippy/tests/ui/author/issue_3849.stdout
@@ -1,14 +1,12 @@
-if_chain! {
-    if let StmtKind::Local(local) = stmt.kind;
-    if let Some(init) = local.init;
-    if let ExprKind::Call(func, args) = init.kind;
-    if let ExprKind::Path(ref qpath) = func.kind;
-    if match_qpath(qpath, &["std", "mem", "transmute"]);
-    if args.len() == 1;
-    if let ExprKind::Path(ref qpath1) = args[0].kind;
-    if match_qpath(qpath1, &["ZPTR"]);
-    if let PatKind::Wild = local.pat.kind;
-    then {
-        // report your lint here
-    }
+if let StmtKind::Local(local) = stmt.kind
+    && let Some(init) = local.init
+    && let ExprKind::Call(func, args) = init.kind
+    && let ExprKind::Path(ref qpath) = func.kind
+    && match_qpath(qpath, &["std", "mem", "transmute"])
+    && args.len() == 1
+    && let ExprKind::Path(ref qpath1) = args[0].kind
+    && match_qpath(qpath1, &["ZPTR"])
+    && let PatKind::Wild = local.pat.kind
+{
+    // report your lint here
 }
diff --git a/src/tools/clippy/tests/ui/author/loop.stdout b/src/tools/clippy/tests/ui/author/loop.stdout
index ceb53fcd4963..94a6436ed547 100644
--- a/src/tools/clippy/tests/ui/author/loop.stdout
+++ b/src/tools/clippy/tests/ui/author/loop.stdout
@@ -1,113 +1,101 @@
-if_chain! {
-    if let Some(higher::ForLoop { pat: pat, arg: arg, body: body, .. }) = higher::ForLoop::hir(expr);
-    if let PatKind::Binding(BindingAnnotation::NONE, _, name, None) = pat.kind;
-    if name.as_str() == "y";
-    if let ExprKind::Struct(qpath, fields, None) = arg.kind;
-    if matches!(qpath, QPath::LangItem(LangItem::Range, _));
-    if fields.len() == 2;
-    if fields[0].ident.as_str() == "start";
-    if let ExprKind::Lit(ref lit) = fields[0].expr.kind;
-    if let LitKind::Int(0, LitIntType::Unsuffixed) = lit.node;
-    if fields[1].ident.as_str() == "end";
-    if let ExprKind::Lit(ref lit1) = fields[1].expr.kind;
-    if let LitKind::Int(10, LitIntType::Unsuffixed) = lit1.node;
-    if let ExprKind::Block(block, None) = body.kind;
-    if block.stmts.len() == 1;
-    if let StmtKind::Local(local) = block.stmts[0].kind;
-    if let Some(init) = local.init;
-    if let ExprKind::Path(ref qpath1) = init.kind;
-    if match_qpath(qpath1, &["y"]);
-    if let PatKind::Binding(BindingAnnotation::NONE, _, name1, None) = local.pat.kind;
-    if name1.as_str() == "z";
-    if block.expr.is_none();
-    then {
-        // report your lint here
-    }
+if let Some(higher::ForLoop { pat: pat, arg: arg, body: body, .. }) = higher::ForLoop::hir(expr)
+    && let PatKind::Binding(BindingAnnotation::NONE, _, name, None) = pat.kind
+    && name.as_str() == "y"
+    && let ExprKind::Struct(qpath, fields, None) = arg.kind
+    && matches!(qpath, QPath::LangItem(LangItem::Range, _))
+    && fields.len() == 2
+    && fields[0].ident.as_str() == "start"
+    && let ExprKind::Lit(ref lit) = fields[0].expr.kind
+    && let LitKind::Int(0, LitIntType::Unsuffixed) = lit.node
+    && fields[1].ident.as_str() == "end"
+    && let ExprKind::Lit(ref lit1) = fields[1].expr.kind
+    && let LitKind::Int(10, LitIntType::Unsuffixed) = lit1.node
+    && let ExprKind::Block(block, None) = body.kind
+    && block.stmts.len() == 1
+    && let StmtKind::Local(local) = block.stmts[0].kind
+    && let Some(init) = local.init
+    && let ExprKind::Path(ref qpath1) = init.kind
+    && match_qpath(qpath1, &["y"])
+    && let PatKind::Binding(BindingAnnotation::NONE, _, name1, None) = local.pat.kind
+    && name1.as_str() == "z"
+    && block.expr.is_none()
+{
+    // report your lint here
 }
-if_chain! {
-    if let Some(higher::ForLoop { pat: pat, arg: arg, body: body, .. }) = higher::ForLoop::hir(expr);
-    if let PatKind::Wild = pat.kind;
-    if let ExprKind::Struct(qpath, fields, None) = arg.kind;
-    if matches!(qpath, QPath::LangItem(LangItem::Range, _));
-    if fields.len() == 2;
-    if fields[0].ident.as_str() == "start";
-    if let ExprKind::Lit(ref lit) = fields[0].expr.kind;
-    if let LitKind::Int(0, LitIntType::Unsuffixed) = lit.node;
-    if fields[1].ident.as_str() == "end";
-    if let ExprKind::Lit(ref lit1) = fields[1].expr.kind;
-    if let LitKind::Int(10, LitIntType::Unsuffixed) = lit1.node;
-    if let ExprKind::Block(block, None) = body.kind;
-    if block.stmts.len() == 1;
-    if let StmtKind::Semi(e) = block.stmts[0].kind;
-    if let ExprKind::Break(destination, None) = e.kind;
-    if destination.label.is_none();
-    if block.expr.is_none();
-    then {
-        // report your lint here
-    }
+if let Some(higher::ForLoop { pat: pat, arg: arg, body: body, .. }) = higher::ForLoop::hir(expr)
+    && let PatKind::Wild = pat.kind
+    && let ExprKind::Struct(qpath, fields, None) = arg.kind
+    && matches!(qpath, QPath::LangItem(LangItem::Range, _))
+    && fields.len() == 2
+    && fields[0].ident.as_str() == "start"
+    && let ExprKind::Lit(ref lit) = fields[0].expr.kind
+    && let LitKind::Int(0, LitIntType::Unsuffixed) = lit.node
+    && fields[1].ident.as_str() == "end"
+    && let ExprKind::Lit(ref lit1) = fields[1].expr.kind
+    && let LitKind::Int(10, LitIntType::Unsuffixed) = lit1.node
+    && let ExprKind::Block(block, None) = body.kind
+    && block.stmts.len() == 1
+    && let StmtKind::Semi(e) = block.stmts[0].kind
+    && let ExprKind::Break(destination, None) = e.kind
+    && destination.label.is_none()
+    && block.expr.is_none()
+{
+    // report your lint here
 }
-if_chain! {
-    if let Some(higher::ForLoop { pat: pat, arg: arg, body: body, .. }) = higher::ForLoop::hir(expr);
-    if let PatKind::Wild = pat.kind;
-    if let ExprKind::Struct(qpath, fields, None) = arg.kind;
-    if matches!(qpath, QPath::LangItem(LangItem::Range, _));
-    if fields.len() == 2;
-    if fields[0].ident.as_str() == "start";
-    if let ExprKind::Lit(ref lit) = fields[0].expr.kind;
-    if let LitKind::Int(0, LitIntType::Unsuffixed) = lit.node;
-    if fields[1].ident.as_str() == "end";
-    if let ExprKind::Lit(ref lit1) = fields[1].expr.kind;
-    if let LitKind::Int(10, LitIntType::Unsuffixed) = lit1.node;
-    if let ExprKind::Block(block, None) = body.kind;
-    if block.stmts.len() == 1;
-    if let StmtKind::Semi(e) = block.stmts[0].kind;
-    if let ExprKind::Break(destination, None) = e.kind;
-    if let Some(label) = destination.label;
-    if label.ident.as_str() == "'label";
-    if block.expr.is_none();
-    then {
-        // report your lint here
-    }
+if let Some(higher::ForLoop { pat: pat, arg: arg, body: body, .. }) = higher::ForLoop::hir(expr)
+    && let PatKind::Wild = pat.kind
+    && let ExprKind::Struct(qpath, fields, None) = arg.kind
+    && matches!(qpath, QPath::LangItem(LangItem::Range, _))
+    && fields.len() == 2
+    && fields[0].ident.as_str() == "start"
+    && let ExprKind::Lit(ref lit) = fields[0].expr.kind
+    && let LitKind::Int(0, LitIntType::Unsuffixed) = lit.node
+    && fields[1].ident.as_str() == "end"
+    && let ExprKind::Lit(ref lit1) = fields[1].expr.kind
+    && let LitKind::Int(10, LitIntType::Unsuffixed) = lit1.node
+    && let ExprKind::Block(block, None) = body.kind
+    && block.stmts.len() == 1
+    && let StmtKind::Semi(e) = block.stmts[0].kind
+    && let ExprKind::Break(destination, None) = e.kind
+    && let Some(label) = destination.label
+    && label.ident.as_str() == "'label"
+    && block.expr.is_none()
+{
+    // report your lint here
 }
-if_chain! {
-    if let Some(higher::While { condition: condition, body: body }) = higher::While::hir(expr);
-    if let ExprKind::Path(ref qpath) = condition.kind;
-    if match_qpath(qpath, &["a"]);
-    if let ExprKind::Block(block, None) = body.kind;
-    if block.stmts.len() == 1;
-    if let StmtKind::Semi(e) = block.stmts[0].kind;
-    if let ExprKind::Break(destination, None) = e.kind;
-    if destination.label.is_none();
-    if block.expr.is_none();
-    then {
-        // report your lint here
-    }
+if let Some(higher::While { condition: condition, body: body }) = higher::While::hir(expr)
+    && let ExprKind::Path(ref qpath) = condition.kind
+    && match_qpath(qpath, &["a"])
+    && let ExprKind::Block(block, None) = body.kind
+    && block.stmts.len() == 1
+    && let StmtKind::Semi(e) = block.stmts[0].kind
+    && let ExprKind::Break(destination, None) = e.kind
+    && destination.label.is_none()
+    && block.expr.is_none()
+{
+    // report your lint here
 }
-if_chain! {
-    if let Some(higher::WhileLet { let_pat: let_pat, let_expr: let_expr, if_then: if_then }) = higher::WhileLet::hir(expr);
-    if let PatKind::Lit(lit_expr) = let_pat.kind;
-    if let ExprKind::Lit(ref lit) = lit_expr.kind;
-    if let LitKind::Bool(true) = lit.node;
-    if let ExprKind::Path(ref qpath) = let_expr.kind;
-    if match_qpath(qpath, &["a"]);
-    if let ExprKind::Block(block, None) = if_then.kind;
-    if block.stmts.len() == 1;
-    if let StmtKind::Semi(e) = block.stmts[0].kind;
-    if let ExprKind::Break(destination, None) = e.kind;
-    if destination.label.is_none();
-    if block.expr.is_none();
-    then {
-        // report your lint here
-    }
+if let Some(higher::WhileLet { let_pat: let_pat, let_expr: let_expr, if_then: if_then }) = higher::WhileLet::hir(expr)
+    && let PatKind::Lit(lit_expr) = let_pat.kind
+    && let ExprKind::Lit(ref lit) = lit_expr.kind
+    && let LitKind::Bool(true) = lit.node
+    && let ExprKind::Path(ref qpath) = let_expr.kind
+    && match_qpath(qpath, &["a"])
+    && let ExprKind::Block(block, None) = if_then.kind
+    && block.stmts.len() == 1
+    && let StmtKind::Semi(e) = block.stmts[0].kind
+    && let ExprKind::Break(destination, None) = e.kind
+    && destination.label.is_none()
+    && block.expr.is_none()
+{
+    // report your lint here
 }
-if_chain! {
-    if let ExprKind::Loop(body, None, LoopSource::Loop, _) = expr.kind;
-    if body.stmts.len() == 1;
-    if let StmtKind::Semi(e) = body.stmts[0].kind;
-    if let ExprKind::Break(destination, None) = e.kind;
-    if destination.label.is_none();
-    if body.expr.is_none();
-    then {
-        // report your lint here
-    }
+if let ExprKind::Loop(body, None, LoopSource::Loop, _) = expr.kind
+    && body.stmts.len() == 1
+    && let StmtKind::Semi(e) = body.stmts[0].kind
+    && let ExprKind::Break(destination, None) = e.kind
+    && destination.label.is_none()
+    && body.expr.is_none()
+{
+    // report your lint here
 }
diff --git a/src/tools/clippy/tests/ui/author/matches.stdout b/src/tools/clippy/tests/ui/author/matches.stdout
index 2cf69a035b4c..88e2ca656a4f 100644
--- a/src/tools/clippy/tests/ui/author/matches.stdout
+++ b/src/tools/clippy/tests/ui/author/matches.stdout
@@ -1,38 +1,36 @@
-if_chain! {
-    if let StmtKind::Local(local) = stmt.kind;
-    if let Some(init) = local.init;
-    if let ExprKind::Match(scrutinee, arms, MatchSource::Normal) = init.kind;
-    if let ExprKind::Lit(ref lit) = scrutinee.kind;
-    if let LitKind::Int(42, LitIntType::Unsuffixed) = lit.node;
-    if arms.len() == 3;
-    if let PatKind::Lit(lit_expr) = arms[0].pat.kind;
-    if let ExprKind::Lit(ref lit1) = lit_expr.kind;
-    if let LitKind::Int(16, LitIntType::Unsuffixed) = lit1.node;
-    if arms[0].guard.is_none();
-    if let ExprKind::Lit(ref lit2) = arms[0].body.kind;
-    if let LitKind::Int(5, LitIntType::Unsuffixed) = lit2.node;
-    if let PatKind::Lit(lit_expr1) = arms[1].pat.kind;
-    if let ExprKind::Lit(ref lit3) = lit_expr1.kind;
-    if let LitKind::Int(17, LitIntType::Unsuffixed) = lit3.node;
-    if arms[1].guard.is_none();
-    if let ExprKind::Block(block, None) = arms[1].body.kind;
-    if block.stmts.len() == 1;
-    if let StmtKind::Local(local1) = block.stmts[0].kind;
-    if let Some(init1) = local1.init;
-    if let ExprKind::Lit(ref lit4) = init1.kind;
-    if let LitKind::Int(3, LitIntType::Unsuffixed) = lit4.node;
-    if let PatKind::Binding(BindingAnnotation::NONE, _, name, None) = local1.pat.kind;
-    if name.as_str() == "x";
-    if let Some(trailing_expr) = block.expr;
-    if let ExprKind::Path(ref qpath) = trailing_expr.kind;
-    if match_qpath(qpath, &["x"]);
-    if let PatKind::Wild = arms[2].pat.kind;
-    if arms[2].guard.is_none();
-    if let ExprKind::Lit(ref lit5) = arms[2].body.kind;
-    if let LitKind::Int(1, LitIntType::Unsuffixed) = lit5.node;
-    if let PatKind::Binding(BindingAnnotation::NONE, _, name1, None) = local.pat.kind;
-    if name1.as_str() == "a";
-    then {
-        // report your lint here
-    }
+if let StmtKind::Local(local) = stmt.kind
+    && let Some(init) = local.init
+    && let ExprKind::Match(scrutinee, arms, MatchSource::Normal) = init.kind
+    && let ExprKind::Lit(ref lit) = scrutinee.kind
+    && let LitKind::Int(42, LitIntType::Unsuffixed) = lit.node
+    && arms.len() == 3
+    && let PatKind::Lit(lit_expr) = arms[0].pat.kind
+    && let ExprKind::Lit(ref lit1) = lit_expr.kind
+    && let LitKind::Int(16, LitIntType::Unsuffixed) = lit1.node
+    && arms[0].guard.is_none()
+    && let ExprKind::Lit(ref lit2) = arms[0].body.kind
+    && let LitKind::Int(5, LitIntType::Unsuffixed) = lit2.node
+    && let PatKind::Lit(lit_expr1) = arms[1].pat.kind
+    && let ExprKind::Lit(ref lit3) = lit_expr1.kind
+    && let LitKind::Int(17, LitIntType::Unsuffixed) = lit3.node
+    && arms[1].guard.is_none()
+    && let ExprKind::Block(block, None) = arms[1].body.kind
+    && block.stmts.len() == 1
+    && let StmtKind::Local(local1) = block.stmts[0].kind
+    && let Some(init1) = local1.init
+    && let ExprKind::Lit(ref lit4) = init1.kind
+    && let LitKind::Int(3, LitIntType::Unsuffixed) = lit4.node
+    && let PatKind::Binding(BindingAnnotation::NONE, _, name, None) = local1.pat.kind
+    && name.as_str() == "x"
+    && let Some(trailing_expr) = block.expr
+    && let ExprKind::Path(ref qpath) = trailing_expr.kind
+    && match_qpath(qpath, &["x"])
+    && let PatKind::Wild = arms[2].pat.kind
+    && arms[2].guard.is_none()
+    && let ExprKind::Lit(ref lit5) = arms[2].body.kind
+    && let LitKind::Int(1, LitIntType::Unsuffixed) = lit5.node
+    && let PatKind::Binding(BindingAnnotation::NONE, _, name1, None) = local.pat.kind
+    && name1.as_str() == "a"
+{
+    // report your lint here
 }
diff --git a/src/tools/clippy/tests/ui/author/repeat.stdout b/src/tools/clippy/tests/ui/author/repeat.stdout
index 471bbce4f418..c2a369610cc1 100644
--- a/src/tools/clippy/tests/ui/author/repeat.stdout
+++ b/src/tools/clippy/tests/ui/author/repeat.stdout
@@ -1,12 +1,10 @@
-if_chain! {
-    if let ExprKind::Repeat(value, length) = expr.kind;
-    if let ExprKind::Lit(ref lit) = value.kind;
-    if let LitKind::Int(1, LitIntType::Unsigned(UintTy::U8)) = lit.node;
-    if let ArrayLen::Body(anon_const) = length;
-    let expr1 = &cx.tcx.hir().body(anon_const.body).value;
-    if let ExprKind::Lit(ref lit1) = expr1.kind;
-    if let LitKind::Int(5, LitIntType::Unsuffixed) = lit1.node;
-    then {
-        // report your lint here
-    }
+if let ExprKind::Repeat(value, length) = expr.kind
+    && let ExprKind::Lit(ref lit) = value.kind
+    && let LitKind::Int(1, LitIntType::Unsigned(UintTy::U8)) = lit.node
+    && let ArrayLen::Body(anon_const) = length
+    && expr1 = &cx.tcx.hir().body(anon_const.body).value
+    && let ExprKind::Lit(ref lit1) = expr1.kind
+    && let LitKind::Int(5, LitIntType::Unsuffixed) = lit1.node
+{
+    // report your lint here
 }
diff --git a/src/tools/clippy/tests/ui/author/struct.stdout b/src/tools/clippy/tests/ui/author/struct.stdout
index b5bbc9e213c6..0b332d5e7d0e 100644
--- a/src/tools/clippy/tests/ui/author/struct.stdout
+++ b/src/tools/clippy/tests/ui/author/struct.stdout
@@ -1,64 +1,56 @@
-if_chain! {
-    if let ExprKind::Struct(qpath, fields, None) = expr.kind;
-    if match_qpath(qpath, &["Test"]);
-    if fields.len() == 1;
-    if fields[0].ident.as_str() == "field";
-    if let ExprKind::If(cond, then, Some(else_expr)) = fields[0].expr.kind;
-    if let ExprKind::DropTemps(expr1) = cond.kind;
-    if let ExprKind::Lit(ref lit) = expr1.kind;
-    if let LitKind::Bool(true) = lit.node;
-    if let ExprKind::Block(block, None) = then.kind;
-    if block.stmts.is_empty();
-    if let Some(trailing_expr) = block.expr;
-    if let ExprKind::Lit(ref lit1) = trailing_expr.kind;
-    if let LitKind::Int(1, LitIntType::Unsuffixed) = lit1.node;
-    if let ExprKind::Block(block1, None) = else_expr.kind;
-    if block1.stmts.is_empty();
-    if let Some(trailing_expr1) = block1.expr;
-    if let ExprKind::Lit(ref lit2) = trailing_expr1.kind;
-    if let LitKind::Int(0, LitIntType::Unsuffixed) = lit2.node;
-    then {
-        // report your lint here
-    }
+if let ExprKind::Struct(qpath, fields, None) = expr.kind
+    && match_qpath(qpath, &["Test"])
+    && fields.len() == 1
+    && fields[0].ident.as_str() == "field"
+    && let ExprKind::If(cond, then, Some(else_expr)) = fields[0].expr.kind
+    && let ExprKind::DropTemps(expr1) = cond.kind
+    && let ExprKind::Lit(ref lit) = expr1.kind
+    && let LitKind::Bool(true) = lit.node
+    && let ExprKind::Block(block, None) = then.kind
+    && block.stmts.is_empty()
+    && let Some(trailing_expr) = block.expr
+    && let ExprKind::Lit(ref lit1) = trailing_expr.kind
+    && let LitKind::Int(1, LitIntType::Unsuffixed) = lit1.node
+    && let ExprKind::Block(block1, None) = else_expr.kind
+    && block1.stmts.is_empty()
+    && let Some(trailing_expr1) = block1.expr
+    && let ExprKind::Lit(ref lit2) = trailing_expr1.kind
+    && let LitKind::Int(0, LitIntType::Unsuffixed) = lit2.node
+{
+    // report your lint here
 }
-if_chain! {
-    if let PatKind::Struct(ref qpath, fields, false) = arm.pat.kind;
-    if match_qpath(qpath, &["Test"]);
-    if fields.len() == 1;
-    if fields[0].ident.as_str() == "field";
-    if let PatKind::Lit(lit_expr) = fields[0].pat.kind;
-    if let ExprKind::Lit(ref lit) = lit_expr.kind;
-    if let LitKind::Int(1, LitIntType::Unsuffixed) = lit.node;
-    if arm.guard.is_none();
-    if let ExprKind::Block(block, None) = arm.body.kind;
-    if block.stmts.is_empty();
-    if block.expr.is_none();
-    then {
-        // report your lint here
-    }
+if let PatKind::Struct(ref qpath, fields, false) = arm.pat.kind
+    && match_qpath(qpath, &["Test"])
+    && fields.len() == 1
+    && fields[0].ident.as_str() == "field"
+    && let PatKind::Lit(lit_expr) = fields[0].pat.kind
+    && let ExprKind::Lit(ref lit) = lit_expr.kind
+    && let LitKind::Int(1, LitIntType::Unsuffixed) = lit.node
+    && arm.guard.is_none()
+    && let ExprKind::Block(block, None) = arm.body.kind
+    && block.stmts.is_empty()
+    && block.expr.is_none()
+{
+    // report your lint here
 }
-if_chain! {
-    if let PatKind::TupleStruct(ref qpath, fields, None) = arm.pat.kind;
-    if match_qpath(qpath, &["TestTuple"]);
-    if fields.len() == 1;
-    if let PatKind::Lit(lit_expr) = fields[0].kind;
-    if let ExprKind::Lit(ref lit) = lit_expr.kind;
-    if let LitKind::Int(1, LitIntType::Unsuffixed) = lit.node;
-    if arm.guard.is_none();
-    if let ExprKind::Block(block, None) = arm.body.kind;
-    if block.stmts.is_empty();
-    if block.expr.is_none();
-    then {
-        // report your lint here
-    }
+if let PatKind::TupleStruct(ref qpath, fields, None) = arm.pat.kind
+    && match_qpath(qpath, &["TestTuple"])
+    && fields.len() == 1
+    && let PatKind::Lit(lit_expr) = fields[0].kind
+    && let ExprKind::Lit(ref lit) = lit_expr.kind
+    && let LitKind::Int(1, LitIntType::Unsuffixed) = lit.node
+    && arm.guard.is_none()
+    && let ExprKind::Block(block, None) = arm.body.kind
+    && block.stmts.is_empty()
+    && block.expr.is_none()
+{
+    // report your lint here
 }
-if_chain! {
-    if let ExprKind::MethodCall(method_name, receiver, args, _) = expr.kind;
-    if method_name.ident.as_str() == "test";
-    if let ExprKind::Path(ref qpath) = receiver.kind;
-    if match_qpath(qpath, &["test_method_call"]);
-    if args.is_empty();
-    then {
-        // report your lint here
-    }
+if let ExprKind::MethodCall(method_name, receiver, args, _) = expr.kind
+    && method_name.ident.as_str() == "test"
+    && let ExprKind::Path(ref qpath) = receiver.kind
+    && match_qpath(qpath, &["test_method_call"])
+    && args.is_empty()
+{
+    // report your lint here
 }
diff --git a/src/tools/clippy/tests/ui/box_default.fixed b/src/tools/clippy/tests/ui/box_default.fixed
new file mode 100644
index 000000000000..911fa856aa0a
--- /dev/null
+++ b/src/tools/clippy/tests/ui/box_default.fixed
@@ -0,0 +1,57 @@
+// run-rustfix
+#![warn(clippy::box_default)]
+
+#[derive(Default)]
+struct ImplementsDefault;
+
+struct OwnDefault;
+
+impl OwnDefault {
+    fn default() -> Self {
+        Self
+    }
+}
+
+macro_rules! outer {
+    ($e: expr) => {
+        $e
+    };
+}
+
+fn main() {
+    let _string: Box<String> = Box::default();
+    let _byte = Box::<u8>::default();
+    let _vec = Box::<std::vec::Vec<u8>>::default();
+    let _impl = Box::<ImplementsDefault>::default();
+    let _impl2 = Box::<ImplementsDefault>::default();
+    let _impl3: Box<ImplementsDefault> = Box::default();
+    let _own = Box::new(OwnDefault::default()); // should not lint
+    let _in_macro = outer!(Box::<std::string::String>::default());
+    let _string_default = outer!(Box::<std::string::String>::default());
+    let _vec2: Box<Vec<ImplementsDefault>> = Box::default();
+    let _vec3: Box<Vec<bool>> = Box::default();
+    let _vec4: Box<_> = Box::<std::vec::Vec<bool>>::default();
+    let _more = ret_ty_fn();
+    call_ty_fn(Box::default());
+}
+
+fn ret_ty_fn() -> Box<bool> {
+    Box::<bool>::default()
+}
+
+#[allow(clippy::boxed_local)]
+fn call_ty_fn(_b: Box<u8>) {
+    issue_9621_dyn_trait();
+}
+
+use std::io::{Read, Result};
+
+impl Read for ImplementsDefault {
+    fn read(&mut self, _: &mut [u8]) -> Result<usize> {
+        Ok(0)
+    }
+}
+
+fn issue_9621_dyn_trait() {
+    let _: Box<dyn Read> = Box::<ImplementsDefault>::default();
+}
diff --git a/src/tools/clippy/tests/ui/box_default.rs b/src/tools/clippy/tests/ui/box_default.rs
index dc522705bc62..20019c2ee5a0 100644
--- a/src/tools/clippy/tests/ui/box_default.rs
+++ b/src/tools/clippy/tests/ui/box_default.rs
@@ -1,3 +1,4 @@
+// run-rustfix
 #![warn(clippy::box_default)]
 
 #[derive(Default)]
@@ -26,6 +27,31 @@ fn main() {
     let _impl3: Box<ImplementsDefault> = Box::new(Default::default());
     let _own = Box::new(OwnDefault::default()); // should not lint
     let _in_macro = outer!(Box::new(String::new()));
-    // false negative: default is from different expansion
+    let _string_default = outer!(Box::new(String::from("")));
     let _vec2: Box<Vec<ImplementsDefault>> = Box::new(vec![]);
+    let _vec3: Box<Vec<bool>> = Box::new(Vec::from([]));
+    let _vec4: Box<_> = Box::new(Vec::from([false; 0]));
+    let _more = ret_ty_fn();
+    call_ty_fn(Box::new(u8::default()));
+}
+
+fn ret_ty_fn() -> Box<bool> {
+    Box::new(bool::default())
+}
+
+#[allow(clippy::boxed_local)]
+fn call_ty_fn(_b: Box<u8>) {
+    issue_9621_dyn_trait();
+}
+
+use std::io::{Read, Result};
+
+impl Read for ImplementsDefault {
+    fn read(&mut self, _: &mut [u8]) -> Result<usize> {
+        Ok(0)
+    }
+}
+
+fn issue_9621_dyn_trait() {
+    let _: Box<dyn Read> = Box::new(ImplementsDefault::default());
 }
diff --git a/src/tools/clippy/tests/ui/box_default.stderr b/src/tools/clippy/tests/ui/box_default.stderr
index b2030e95acb1..5ea410331afb 100644
--- a/src/tools/clippy/tests/ui/box_default.stderr
+++ b/src/tools/clippy/tests/ui/box_default.stderr
@@ -1,59 +1,88 @@
 error: `Box::new(_)` of default value
-  --> $DIR/box_default.rs:21:32
+  --> $DIR/box_default.rs:22:32
    |
 LL |     let _string: Box<String> = Box::new(Default::default());
-   |                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `Box::default()`
    |
-   = help: use `Box::default()` instead
    = note: `-D clippy::box-default` implied by `-D warnings`
 
 error: `Box::new(_)` of default value
-  --> $DIR/box_default.rs:22:17
+  --> $DIR/box_default.rs:23:17
    |
 LL |     let _byte = Box::new(u8::default());
-   |                 ^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = help: use `Box::default()` instead
+   |                 ^^^^^^^^^^^^^^^^^^^^^^^ help: try: `Box::<u8>::default()`
 
 error: `Box::new(_)` of default value
-  --> $DIR/box_default.rs:23:16
+  --> $DIR/box_default.rs:24:16
    |
 LL |     let _vec = Box::new(Vec::<u8>::new());
-   |                ^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = help: use `Box::default()` instead
+   |                ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `Box::<std::vec::Vec<u8>>::default()`
 
 error: `Box::new(_)` of default value
-  --> $DIR/box_default.rs:24:17
+  --> $DIR/box_default.rs:25:17
    |
 LL |     let _impl = Box::new(ImplementsDefault::default());
-   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = help: use `Box::default()` instead
+   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `Box::<ImplementsDefault>::default()`
 
 error: `Box::new(_)` of default value
-  --> $DIR/box_default.rs:25:18
+  --> $DIR/box_default.rs:26:18
    |
 LL |     let _impl2 = Box::new(<ImplementsDefault as Default>::default());
-   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = help: use `Box::default()` instead
+   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `Box::<ImplementsDefault>::default()`
 
 error: `Box::new(_)` of default value
-  --> $DIR/box_default.rs:26:42
+  --> $DIR/box_default.rs:27:42
    |
 LL |     let _impl3: Box<ImplementsDefault> = Box::new(Default::default());
-   |                                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = help: use `Box::default()` instead
+   |                                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `Box::default()`
 
 error: `Box::new(_)` of default value
-  --> $DIR/box_default.rs:28:28
+  --> $DIR/box_default.rs:29:28
    |
 LL |     let _in_macro = outer!(Box::new(String::new()));
-   |                            ^^^^^^^^^^^^^^^^^^^^^^^
+   |                            ^^^^^^^^^^^^^^^^^^^^^^^ help: try: `Box::<std::string::String>::default()`
+
+error: `Box::new(_)` of default value
+  --> $DIR/box_default.rs:30:34
    |
-   = help: use `Box::default()` instead
+LL |     let _string_default = outer!(Box::new(String::from("")));
+   |                                  ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `Box::<std::string::String>::default()`
 
-error: aborting due to 7 previous errors
+error: `Box::new(_)` of default value
+  --> $DIR/box_default.rs:31:46
+   |
+LL |     let _vec2: Box<Vec<ImplementsDefault>> = Box::new(vec![]);
+   |                                              ^^^^^^^^^^^^^^^^ help: try: `Box::default()`
+
+error: `Box::new(_)` of default value
+  --> $DIR/box_default.rs:32:33
+   |
+LL |     let _vec3: Box<Vec<bool>> = Box::new(Vec::from([]));
+   |                                 ^^^^^^^^^^^^^^^^^^^^^^^ help: try: `Box::default()`
+
+error: `Box::new(_)` of default value
+  --> $DIR/box_default.rs:33:25
+   |
+LL |     let _vec4: Box<_> = Box::new(Vec::from([false; 0]));
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `Box::<std::vec::Vec<bool>>::default()`
+
+error: `Box::new(_)` of default value
+  --> $DIR/box_default.rs:35:16
+   |
+LL |     call_ty_fn(Box::new(u8::default()));
+   |                ^^^^^^^^^^^^^^^^^^^^^^^ help: try: `Box::default()`
+
+error: `Box::new(_)` of default value
+  --> $DIR/box_default.rs:39:5
+   |
+LL |     Box::new(bool::default())
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `Box::<bool>::default()`
+
+error: `Box::new(_)` of default value
+  --> $DIR/box_default.rs:56:28
+   |
+LL |     let _: Box<dyn Read> = Box::new(ImplementsDefault::default());
+   |                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `Box::<ImplementsDefault>::default()`
+
+error: aborting due to 14 previous errors
 
diff --git a/src/tools/clippy/tests/ui/box_default_no_std.rs b/src/tools/clippy/tests/ui/box_default_no_std.rs
new file mode 100644
index 000000000000..4326abc9a541
--- /dev/null
+++ b/src/tools/clippy/tests/ui/box_default_no_std.rs
@@ -0,0 +1,33 @@
+#![feature(lang_items, start, libc)]
+#![warn(clippy::box_default)]
+#![no_std]
+
+pub struct NotBox<T> {
+    _value: T,
+}
+
+impl<T> NotBox<T> {
+    pub fn new(value: T) -> Self {
+        Self { _value: value }
+    }
+}
+
+impl<T: Default> Default for NotBox<T> {
+    fn default() -> Self {
+        Self::new(T::default())
+    }
+}
+
+#[start]
+fn main(_argc: isize, _argv: *const *const u8) -> isize {
+    let _p = NotBox::new(isize::default());
+    0
+}
+
+#[panic_handler]
+fn panic(_info: &core::panic::PanicInfo) -> ! {
+    loop {}
+}
+
+#[lang = "eh_personality"]
+extern "C" fn eh_personality() {}
diff --git a/src/tools/clippy/tests/ui/cast_abs_to_unsigned.fixed b/src/tools/clippy/tests/ui/cast_abs_to_unsigned.fixed
index a37f3fec20f1..e6bf944c7a5e 100644
--- a/src/tools/clippy/tests/ui/cast_abs_to_unsigned.fixed
+++ b/src/tools/clippy/tests/ui/cast_abs_to_unsigned.fixed
@@ -1,6 +1,8 @@
 // run-rustfix
+
+#![feature(custom_inner_attributes)]
 #![warn(clippy::cast_abs_to_unsigned)]
-#![allow(clippy::uninlined_format_args)]
+#![allow(clippy::uninlined_format_args, unused)]
 
 fn main() {
     let x: i32 = -42;
@@ -30,3 +32,17 @@ fn main() {
 
     let _ = (x as i64 - y as i64).unsigned_abs() as u32;
 }
+
+fn msrv_1_50() {
+    #![clippy::msrv = "1.50"]
+
+    let x: i32 = 10;
+    assert_eq!(10u32, x.abs() as u32);
+}
+
+fn msrv_1_51() {
+    #![clippy::msrv = "1.51"]
+
+    let x: i32 = 10;
+    assert_eq!(10u32, x.unsigned_abs());
+}
diff --git a/src/tools/clippy/tests/ui/cast_abs_to_unsigned.rs b/src/tools/clippy/tests/ui/cast_abs_to_unsigned.rs
index 5706930af5a0..c87320b5209d 100644
--- a/src/tools/clippy/tests/ui/cast_abs_to_unsigned.rs
+++ b/src/tools/clippy/tests/ui/cast_abs_to_unsigned.rs
@@ -1,6 +1,8 @@
 // run-rustfix
+
+#![feature(custom_inner_attributes)]
 #![warn(clippy::cast_abs_to_unsigned)]
-#![allow(clippy::uninlined_format_args)]
+#![allow(clippy::uninlined_format_args, unused)]
 
 fn main() {
     let x: i32 = -42;
@@ -30,3 +32,17 @@ fn main() {
 
     let _ = (x as i64 - y as i64).abs() as u32;
 }
+
+fn msrv_1_50() {
+    #![clippy::msrv = "1.50"]
+
+    let x: i32 = 10;
+    assert_eq!(10u32, x.abs() as u32);
+}
+
+fn msrv_1_51() {
+    #![clippy::msrv = "1.51"]
+
+    let x: i32 = 10;
+    assert_eq!(10u32, x.abs() as u32);
+}
diff --git a/src/tools/clippy/tests/ui/cast_abs_to_unsigned.stderr b/src/tools/clippy/tests/ui/cast_abs_to_unsigned.stderr
index 7cea11c183d2..1b39c554b038 100644
--- a/src/tools/clippy/tests/ui/cast_abs_to_unsigned.stderr
+++ b/src/tools/clippy/tests/ui/cast_abs_to_unsigned.stderr
@@ -1,5 +1,5 @@
 error: casting the result of `i32::abs()` to u32
-  --> $DIR/cast_abs_to_unsigned.rs:7:18
+  --> $DIR/cast_abs_to_unsigned.rs:9:18
    |
 LL |     let y: u32 = x.abs() as u32;
    |                  ^^^^^^^^^^^^^^ help: replace with: `x.unsigned_abs()`
@@ -7,100 +7,106 @@ LL |     let y: u32 = x.abs() as u32;
    = note: `-D clippy::cast-abs-to-unsigned` implied by `-D warnings`
 
 error: casting the result of `i32::abs()` to usize
-  --> $DIR/cast_abs_to_unsigned.rs:11:20
+  --> $DIR/cast_abs_to_unsigned.rs:13:20
    |
 LL |     let _: usize = a.abs() as usize;
    |                    ^^^^^^^ help: replace with: `a.unsigned_abs()`
 
 error: casting the result of `i32::abs()` to usize
-  --> $DIR/cast_abs_to_unsigned.rs:12:20
+  --> $DIR/cast_abs_to_unsigned.rs:14:20
    |
 LL |     let _: usize = a.abs() as _;
    |                    ^^^^^^^ help: replace with: `a.unsigned_abs()`
 
 error: casting the result of `i32::abs()` to usize
-  --> $DIR/cast_abs_to_unsigned.rs:13:13
+  --> $DIR/cast_abs_to_unsigned.rs:15:13
    |
 LL |     let _ = a.abs() as usize;
    |             ^^^^^^^ help: replace with: `a.unsigned_abs()`
 
 error: casting the result of `i64::abs()` to usize
-  --> $DIR/cast_abs_to_unsigned.rs:16:13
+  --> $DIR/cast_abs_to_unsigned.rs:18:13
    |
 LL |     let _ = a.abs() as usize;
    |             ^^^^^^^ help: replace with: `a.unsigned_abs()`
 
 error: casting the result of `i64::abs()` to u8
-  --> $DIR/cast_abs_to_unsigned.rs:17:13
+  --> $DIR/cast_abs_to_unsigned.rs:19:13
    |
 LL |     let _ = a.abs() as u8;
    |             ^^^^^^^ help: replace with: `a.unsigned_abs()`
 
 error: casting the result of `i64::abs()` to u16
-  --> $DIR/cast_abs_to_unsigned.rs:18:13
+  --> $DIR/cast_abs_to_unsigned.rs:20:13
    |
 LL |     let _ = a.abs() as u16;
    |             ^^^^^^^ help: replace with: `a.unsigned_abs()`
 
 error: casting the result of `i64::abs()` to u32
-  --> $DIR/cast_abs_to_unsigned.rs:19:13
+  --> $DIR/cast_abs_to_unsigned.rs:21:13
    |
 LL |     let _ = a.abs() as u32;
    |             ^^^^^^^ help: replace with: `a.unsigned_abs()`
 
 error: casting the result of `i64::abs()` to u64
-  --> $DIR/cast_abs_to_unsigned.rs:20:13
+  --> $DIR/cast_abs_to_unsigned.rs:22:13
    |
 LL |     let _ = a.abs() as u64;
    |             ^^^^^^^^^^^^^^ help: replace with: `a.unsigned_abs()`
 
 error: casting the result of `i64::abs()` to u128
-  --> $DIR/cast_abs_to_unsigned.rs:21:13
+  --> $DIR/cast_abs_to_unsigned.rs:23:13
    |
 LL |     let _ = a.abs() as u128;
    |             ^^^^^^^ help: replace with: `a.unsigned_abs()`
 
 error: casting the result of `isize::abs()` to usize
-  --> $DIR/cast_abs_to_unsigned.rs:24:13
+  --> $DIR/cast_abs_to_unsigned.rs:26:13
    |
 LL |     let _ = a.abs() as usize;
    |             ^^^^^^^^^^^^^^^^ help: replace with: `a.unsigned_abs()`
 
 error: casting the result of `isize::abs()` to u8
-  --> $DIR/cast_abs_to_unsigned.rs:25:13
+  --> $DIR/cast_abs_to_unsigned.rs:27:13
    |
 LL |     let _ = a.abs() as u8;
    |             ^^^^^^^ help: replace with: `a.unsigned_abs()`
 
 error: casting the result of `isize::abs()` to u16
-  --> $DIR/cast_abs_to_unsigned.rs:26:13
+  --> $DIR/cast_abs_to_unsigned.rs:28:13
    |
 LL |     let _ = a.abs() as u16;
    |             ^^^^^^^ help: replace with: `a.unsigned_abs()`
 
 error: casting the result of `isize::abs()` to u32
-  --> $DIR/cast_abs_to_unsigned.rs:27:13
+  --> $DIR/cast_abs_to_unsigned.rs:29:13
    |
 LL |     let _ = a.abs() as u32;
    |             ^^^^^^^ help: replace with: `a.unsigned_abs()`
 
 error: casting the result of `isize::abs()` to u64
-  --> $DIR/cast_abs_to_unsigned.rs:28:13
+  --> $DIR/cast_abs_to_unsigned.rs:30:13
    |
 LL |     let _ = a.abs() as u64;
    |             ^^^^^^^ help: replace with: `a.unsigned_abs()`
 
 error: casting the result of `isize::abs()` to u128
-  --> $DIR/cast_abs_to_unsigned.rs:29:13
+  --> $DIR/cast_abs_to_unsigned.rs:31:13
    |
 LL |     let _ = a.abs() as u128;
    |             ^^^^^^^ help: replace with: `a.unsigned_abs()`
 
 error: casting the result of `i64::abs()` to u32
-  --> $DIR/cast_abs_to_unsigned.rs:31:13
+  --> $DIR/cast_abs_to_unsigned.rs:33:13
    |
 LL |     let _ = (x as i64 - y as i64).abs() as u32;
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace with: `(x as i64 - y as i64).unsigned_abs()`
 
-error: aborting due to 17 previous errors
+error: casting the result of `i32::abs()` to u32
+  --> $DIR/cast_abs_to_unsigned.rs:47:23
+   |
+LL |     assert_eq!(10u32, x.abs() as u32);
+   |                       ^^^^^^^^^^^^^^ help: replace with: `x.unsigned_abs()`
+
+error: aborting due to 18 previous errors
 
diff --git a/src/tools/clippy/tests/ui/cast_lossless_bool.fixed b/src/tools/clippy/tests/ui/cast_lossless_bool.fixed
index 9e2da45c3785..af13b755e310 100644
--- a/src/tools/clippy/tests/ui/cast_lossless_bool.fixed
+++ b/src/tools/clippy/tests/ui/cast_lossless_bool.fixed
@@ -1,5 +1,6 @@
 // run-rustfix
 
+#![feature(custom_inner_attributes)]
 #![allow(dead_code)]
 #![warn(clippy::cast_lossless)]
 
@@ -40,3 +41,15 @@ mod cast_lossless_in_impl {
         }
     }
 }
+
+fn msrv_1_27() {
+    #![clippy::msrv = "1.27"]
+
+    let _ = true as u8;
+}
+
+fn msrv_1_28() {
+    #![clippy::msrv = "1.28"]
+
+    let _ = u8::from(true);
+}
diff --git a/src/tools/clippy/tests/ui/cast_lossless_bool.rs b/src/tools/clippy/tests/ui/cast_lossless_bool.rs
index b6f6c59a01f9..3b06af899c60 100644
--- a/src/tools/clippy/tests/ui/cast_lossless_bool.rs
+++ b/src/tools/clippy/tests/ui/cast_lossless_bool.rs
@@ -1,5 +1,6 @@
 // run-rustfix
 
+#![feature(custom_inner_attributes)]
 #![allow(dead_code)]
 #![warn(clippy::cast_lossless)]
 
@@ -40,3 +41,15 @@ mod cast_lossless_in_impl {
         }
     }
 }
+
+fn msrv_1_27() {
+    #![clippy::msrv = "1.27"]
+
+    let _ = true as u8;
+}
+
+fn msrv_1_28() {
+    #![clippy::msrv = "1.28"]
+
+    let _ = true as u8;
+}
diff --git a/src/tools/clippy/tests/ui/cast_lossless_bool.stderr b/src/tools/clippy/tests/ui/cast_lossless_bool.stderr
index 6b148336011d..768b033d10a2 100644
--- a/src/tools/clippy/tests/ui/cast_lossless_bool.stderr
+++ b/src/tools/clippy/tests/ui/cast_lossless_bool.stderr
@@ -1,5 +1,5 @@
 error: casting `bool` to `u8` is more cleanly stated with `u8::from(_)`
-  --> $DIR/cast_lossless_bool.rs:8:13
+  --> $DIR/cast_lossless_bool.rs:9:13
    |
 LL |     let _ = true as u8;
    |             ^^^^^^^^^^ help: try: `u8::from(true)`
@@ -7,76 +7,82 @@ LL |     let _ = true as u8;
    = note: `-D clippy::cast-lossless` implied by `-D warnings`
 
 error: casting `bool` to `u16` is more cleanly stated with `u16::from(_)`
-  --> $DIR/cast_lossless_bool.rs:9:13
+  --> $DIR/cast_lossless_bool.rs:10:13
    |
 LL |     let _ = true as u16;
    |             ^^^^^^^^^^^ help: try: `u16::from(true)`
 
 error: casting `bool` to `u32` is more cleanly stated with `u32::from(_)`
-  --> $DIR/cast_lossless_bool.rs:10:13
+  --> $DIR/cast_lossless_bool.rs:11:13
    |
 LL |     let _ = true as u32;
    |             ^^^^^^^^^^^ help: try: `u32::from(true)`
 
 error: casting `bool` to `u64` is more cleanly stated with `u64::from(_)`
-  --> $DIR/cast_lossless_bool.rs:11:13
+  --> $DIR/cast_lossless_bool.rs:12:13
    |
 LL |     let _ = true as u64;
    |             ^^^^^^^^^^^ help: try: `u64::from(true)`
 
 error: casting `bool` to `u128` is more cleanly stated with `u128::from(_)`
-  --> $DIR/cast_lossless_bool.rs:12:13
+  --> $DIR/cast_lossless_bool.rs:13:13
    |
 LL |     let _ = true as u128;
    |             ^^^^^^^^^^^^ help: try: `u128::from(true)`
 
 error: casting `bool` to `usize` is more cleanly stated with `usize::from(_)`
-  --> $DIR/cast_lossless_bool.rs:13:13
+  --> $DIR/cast_lossless_bool.rs:14:13
    |
 LL |     let _ = true as usize;
    |             ^^^^^^^^^^^^^ help: try: `usize::from(true)`
 
 error: casting `bool` to `i8` is more cleanly stated with `i8::from(_)`
-  --> $DIR/cast_lossless_bool.rs:15:13
+  --> $DIR/cast_lossless_bool.rs:16:13
    |
 LL |     let _ = true as i8;
    |             ^^^^^^^^^^ help: try: `i8::from(true)`
 
 error: casting `bool` to `i16` is more cleanly stated with `i16::from(_)`
-  --> $DIR/cast_lossless_bool.rs:16:13
+  --> $DIR/cast_lossless_bool.rs:17:13
    |
 LL |     let _ = true as i16;
    |             ^^^^^^^^^^^ help: try: `i16::from(true)`
 
 error: casting `bool` to `i32` is more cleanly stated with `i32::from(_)`
-  --> $DIR/cast_lossless_bool.rs:17:13
+  --> $DIR/cast_lossless_bool.rs:18:13
    |
 LL |     let _ = true as i32;
    |             ^^^^^^^^^^^ help: try: `i32::from(true)`
 
 error: casting `bool` to `i64` is more cleanly stated with `i64::from(_)`
-  --> $DIR/cast_lossless_bool.rs:18:13
+  --> $DIR/cast_lossless_bool.rs:19:13
    |
 LL |     let _ = true as i64;
    |             ^^^^^^^^^^^ help: try: `i64::from(true)`
 
 error: casting `bool` to `i128` is more cleanly stated with `i128::from(_)`
-  --> $DIR/cast_lossless_bool.rs:19:13
+  --> $DIR/cast_lossless_bool.rs:20:13
    |
 LL |     let _ = true as i128;
    |             ^^^^^^^^^^^^ help: try: `i128::from(true)`
 
 error: casting `bool` to `isize` is more cleanly stated with `isize::from(_)`
-  --> $DIR/cast_lossless_bool.rs:20:13
+  --> $DIR/cast_lossless_bool.rs:21:13
    |
 LL |     let _ = true as isize;
    |             ^^^^^^^^^^^^^ help: try: `isize::from(true)`
 
 error: casting `bool` to `u16` is more cleanly stated with `u16::from(_)`
-  --> $DIR/cast_lossless_bool.rs:23:13
+  --> $DIR/cast_lossless_bool.rs:24:13
    |
 LL |     let _ = (true | false) as u16;
    |             ^^^^^^^^^^^^^^^^^^^^^ help: try: `u16::from(true | false)`
 
-error: aborting due to 13 previous errors
+error: casting `bool` to `u8` is more cleanly stated with `u8::from(_)`
+  --> $DIR/cast_lossless_bool.rs:54:13
+   |
+LL |     let _ = true as u8;
+   |             ^^^^^^^^^^ help: try: `u8::from(true)`
+
+error: aborting due to 14 previous errors
 
diff --git a/src/tools/clippy/tests/ui/cast_nan_to_int.rs b/src/tools/clippy/tests/ui/cast_nan_to_int.rs
new file mode 100644
index 000000000000..287c5aa216bd
--- /dev/null
+++ b/src/tools/clippy/tests/ui/cast_nan_to_int.rs
@@ -0,0 +1,18 @@
+#![warn(clippy::cast_nan_to_int)]
+#![allow(clippy::eq_op)]
+
+fn main() {
+    let _ = (0.0_f32 / -0.0) as usize;
+    let _ = (f64::INFINITY * -0.0) as usize;
+    let _ = (0.0 * f32::INFINITY) as usize;
+
+    let _ = (f64::INFINITY + f64::NEG_INFINITY) as usize;
+    let _ = (f32::INFINITY - f32::INFINITY) as usize;
+    let _ = (f32::INFINITY / f32::NEG_INFINITY) as usize;
+
+    // those won't be linted:
+    let _ = (1.0_f32 / 0.0) as usize;
+    let _ = (f32::INFINITY * f32::NEG_INFINITY) as usize;
+    let _ = (f32::INFINITY - f32::NEG_INFINITY) as usize;
+    let _ = (f64::INFINITY - 0.0) as usize;
+}
diff --git a/src/tools/clippy/tests/ui/cast_nan_to_int.stderr b/src/tools/clippy/tests/ui/cast_nan_to_int.stderr
new file mode 100644
index 000000000000..3539be75a19d
--- /dev/null
+++ b/src/tools/clippy/tests/ui/cast_nan_to_int.stderr
@@ -0,0 +1,51 @@
+error: casting a known NaN to usize
+  --> $DIR/cast_nan_to_int.rs:5:13
+   |
+LL |     let _ = (0.0_f32 / -0.0) as usize;
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: this always evaluates to 0
+   = note: `-D clippy::cast-nan-to-int` implied by `-D warnings`
+
+error: casting a known NaN to usize
+  --> $DIR/cast_nan_to_int.rs:6:13
+   |
+LL |     let _ = (f64::INFINITY * -0.0) as usize;
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: this always evaluates to 0
+
+error: casting a known NaN to usize
+  --> $DIR/cast_nan_to_int.rs:7:13
+   |
+LL |     let _ = (0.0 * f32::INFINITY) as usize;
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: this always evaluates to 0
+
+error: casting a known NaN to usize
+  --> $DIR/cast_nan_to_int.rs:9:13
+   |
+LL |     let _ = (f64::INFINITY + f64::NEG_INFINITY) as usize;
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: this always evaluates to 0
+
+error: casting a known NaN to usize
+  --> $DIR/cast_nan_to_int.rs:10:13
+   |
+LL |     let _ = (f32::INFINITY - f32::INFINITY) as usize;
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: this always evaluates to 0
+
+error: casting a known NaN to usize
+  --> $DIR/cast_nan_to_int.rs:11:13
+   |
+LL |     let _ = (f32::INFINITY / f32::NEG_INFINITY) as usize;
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: this always evaluates to 0
+
+error: aborting due to 6 previous errors
+
diff --git a/src/tools/clippy/tests/ui/cfg_attr_rustfmt.fixed b/src/tools/clippy/tests/ui/cfg_attr_rustfmt.fixed
index 061a4ab9b2ef..8a5645b22ed1 100644
--- a/src/tools/clippy/tests/ui/cfg_attr_rustfmt.fixed
+++ b/src/tools/clippy/tests/ui/cfg_attr_rustfmt.fixed
@@ -1,5 +1,5 @@
 // run-rustfix
-#![feature(stmt_expr_attributes)]
+#![feature(stmt_expr_attributes, custom_inner_attributes)]
 
 #![allow(unused, clippy::no_effect, clippy::unnecessary_operation)]
 #![warn(clippy::deprecated_cfg_attr)]
@@ -29,3 +29,17 @@ mod foo {
 
     pub fn f() {}
 }
+
+fn msrv_1_29() {
+    #![clippy::msrv = "1.29"]
+
+    #[cfg_attr(rustfmt, rustfmt::skip)]
+    1+29;
+}
+
+fn msrv_1_30() {
+    #![clippy::msrv = "1.30"]
+
+    #[rustfmt::skip]
+    1+30;
+}
diff --git a/src/tools/clippy/tests/ui/cfg_attr_rustfmt.rs b/src/tools/clippy/tests/ui/cfg_attr_rustfmt.rs
index 035169fab85b..2fb140efae76 100644
--- a/src/tools/clippy/tests/ui/cfg_attr_rustfmt.rs
+++ b/src/tools/clippy/tests/ui/cfg_attr_rustfmt.rs
@@ -1,5 +1,5 @@
 // run-rustfix
-#![feature(stmt_expr_attributes)]
+#![feature(stmt_expr_attributes, custom_inner_attributes)]
 
 #![allow(unused, clippy::no_effect, clippy::unnecessary_operation)]
 #![warn(clippy::deprecated_cfg_attr)]
@@ -29,3 +29,17 @@ mod foo {
 
     pub fn f() {}
 }
+
+fn msrv_1_29() {
+    #![clippy::msrv = "1.29"]
+
+    #[cfg_attr(rustfmt, rustfmt::skip)]
+    1+29;
+}
+
+fn msrv_1_30() {
+    #![clippy::msrv = "1.30"]
+
+    #[cfg_attr(rustfmt, rustfmt::skip)]
+    1+30;
+}
diff --git a/src/tools/clippy/tests/ui/cfg_attr_rustfmt.stderr b/src/tools/clippy/tests/ui/cfg_attr_rustfmt.stderr
index c1efd47db90b..08df7b2b39a0 100644
--- a/src/tools/clippy/tests/ui/cfg_attr_rustfmt.stderr
+++ b/src/tools/clippy/tests/ui/cfg_attr_rustfmt.stderr
@@ -12,5 +12,11 @@ error: `cfg_attr` is deprecated for rustfmt and got replaced by tool attributes
 LL | #[cfg_attr(rustfmt, rustfmt_skip)]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use: `#[rustfmt::skip]`
 
-error: aborting due to 2 previous errors
+error: `cfg_attr` is deprecated for rustfmt and got replaced by tool attributes
+  --> $DIR/cfg_attr_rustfmt.rs:43:5
+   |
+LL |     #[cfg_attr(rustfmt, rustfmt::skip)]
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use: `#[rustfmt::skip]`
+
+error: aborting due to 3 previous errors
 
diff --git a/src/tools/clippy/tests/ui/checked_conversions.fixed b/src/tools/clippy/tests/ui/checked_conversions.fixed
index cb7100bc9efa..f936957cb40c 100644
--- a/src/tools/clippy/tests/ui/checked_conversions.fixed
+++ b/src/tools/clippy/tests/ui/checked_conversions.fixed
@@ -1,7 +1,9 @@
 // run-rustfix
 
+#![feature(custom_inner_attributes)]
 #![allow(
     clippy::cast_lossless,
+    unused,
     // Int::max_value will be deprecated in the future
     deprecated,
 )]
@@ -76,4 +78,18 @@ pub const fn issue_8898(i: u32) -> bool {
     i <= i32::MAX as u32
 }
 
+fn msrv_1_33() {
+    #![clippy::msrv = "1.33"]
+
+    let value: i64 = 33;
+    let _ = value <= (u32::MAX as i64) && value >= 0;
+}
+
+fn msrv_1_34() {
+    #![clippy::msrv = "1.34"]
+
+    let value: i64 = 34;
+    let _ = u32::try_from(value).is_ok();
+}
+
 fn main() {}
diff --git a/src/tools/clippy/tests/ui/checked_conversions.rs b/src/tools/clippy/tests/ui/checked_conversions.rs
index ed4e0692388a..77aec713ff31 100644
--- a/src/tools/clippy/tests/ui/checked_conversions.rs
+++ b/src/tools/clippy/tests/ui/checked_conversions.rs
@@ -1,7 +1,9 @@
 // run-rustfix
 
+#![feature(custom_inner_attributes)]
 #![allow(
     clippy::cast_lossless,
+    unused,
     // Int::max_value will be deprecated in the future
     deprecated,
 )]
@@ -76,4 +78,18 @@ pub const fn issue_8898(i: u32) -> bool {
     i <= i32::MAX as u32
 }
 
+fn msrv_1_33() {
+    #![clippy::msrv = "1.33"]
+
+    let value: i64 = 33;
+    let _ = value <= (u32::MAX as i64) && value >= 0;
+}
+
+fn msrv_1_34() {
+    #![clippy::msrv = "1.34"]
+
+    let value: i64 = 34;
+    let _ = value <= (u32::MAX as i64) && value >= 0;
+}
+
 fn main() {}
diff --git a/src/tools/clippy/tests/ui/checked_conversions.stderr b/src/tools/clippy/tests/ui/checked_conversions.stderr
index 2e518040561c..b2bf7af8daf8 100644
--- a/src/tools/clippy/tests/ui/checked_conversions.stderr
+++ b/src/tools/clippy/tests/ui/checked_conversions.stderr
@@ -1,5 +1,5 @@
 error: checked cast can be simplified
-  --> $DIR/checked_conversions.rs:15:13
+  --> $DIR/checked_conversions.rs:17:13
    |
 LL |     let _ = value <= (u32::max_value() as i64) && value >= 0;
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `u32::try_from(value).is_ok()`
@@ -7,94 +7,100 @@ LL |     let _ = value <= (u32::max_value() as i64) && value >= 0;
    = note: `-D clippy::checked-conversions` implied by `-D warnings`
 
 error: checked cast can be simplified
-  --> $DIR/checked_conversions.rs:16:13
+  --> $DIR/checked_conversions.rs:18:13
    |
 LL |     let _ = value <= (u32::MAX as i64) && value >= 0;
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `u32::try_from(value).is_ok()`
 
 error: checked cast can be simplified
-  --> $DIR/checked_conversions.rs:20:13
+  --> $DIR/checked_conversions.rs:22:13
    |
 LL |     let _ = value <= i64::from(u16::max_value()) && value >= 0;
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `u16::try_from(value).is_ok()`
 
 error: checked cast can be simplified
-  --> $DIR/checked_conversions.rs:21:13
+  --> $DIR/checked_conversions.rs:23:13
    |
 LL |     let _ = value <= i64::from(u16::MAX) && value >= 0;
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `u16::try_from(value).is_ok()`
 
 error: checked cast can be simplified
-  --> $DIR/checked_conversions.rs:25:13
+  --> $DIR/checked_conversions.rs:27:13
    |
 LL |     let _ = value <= (u8::max_value() as isize) && value >= 0;
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `u8::try_from(value).is_ok()`
 
 error: checked cast can be simplified
-  --> $DIR/checked_conversions.rs:26:13
+  --> $DIR/checked_conversions.rs:28:13
    |
 LL |     let _ = value <= (u8::MAX as isize) && value >= 0;
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `u8::try_from(value).is_ok()`
 
 error: checked cast can be simplified
-  --> $DIR/checked_conversions.rs:32:13
+  --> $DIR/checked_conversions.rs:34:13
    |
 LL |     let _ = value <= (i32::max_value() as i64) && value >= (i32::min_value() as i64);
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `i32::try_from(value).is_ok()`
 
 error: checked cast can be simplified
-  --> $DIR/checked_conversions.rs:33:13
+  --> $DIR/checked_conversions.rs:35:13
    |
 LL |     let _ = value <= (i32::MAX as i64) && value >= (i32::MIN as i64);
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `i32::try_from(value).is_ok()`
 
 error: checked cast can be simplified
-  --> $DIR/checked_conversions.rs:37:13
+  --> $DIR/checked_conversions.rs:39:13
    |
 LL |     let _ = value <= i64::from(i16::max_value()) && value >= i64::from(i16::min_value());
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `i16::try_from(value).is_ok()`
 
 error: checked cast can be simplified
-  --> $DIR/checked_conversions.rs:38:13
+  --> $DIR/checked_conversions.rs:40:13
    |
 LL |     let _ = value <= i64::from(i16::MAX) && value >= i64::from(i16::MIN);
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `i16::try_from(value).is_ok()`
 
 error: checked cast can be simplified
-  --> $DIR/checked_conversions.rs:44:13
+  --> $DIR/checked_conversions.rs:46:13
    |
 LL |     let _ = value <= i32::max_value() as u32;
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `i32::try_from(value).is_ok()`
 
 error: checked cast can be simplified
-  --> $DIR/checked_conversions.rs:45:13
+  --> $DIR/checked_conversions.rs:47:13
    |
 LL |     let _ = value <= i32::MAX as u32;
    |             ^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `i32::try_from(value).is_ok()`
 
 error: checked cast can be simplified
-  --> $DIR/checked_conversions.rs:49:13
+  --> $DIR/checked_conversions.rs:51:13
    |
 LL |     let _ = value <= isize::max_value() as usize && value as i32 == 5;
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `isize::try_from(value).is_ok()`
 
 error: checked cast can be simplified
-  --> $DIR/checked_conversions.rs:50:13
+  --> $DIR/checked_conversions.rs:52:13
    |
 LL |     let _ = value <= isize::MAX as usize && value as i32 == 5;
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `isize::try_from(value).is_ok()`
 
 error: checked cast can be simplified
-  --> $DIR/checked_conversions.rs:54:13
+  --> $DIR/checked_conversions.rs:56:13
    |
 LL |     let _ = value <= u16::max_value() as u32 && value as i32 == 5;
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `u16::try_from(value).is_ok()`
 
 error: checked cast can be simplified
-  --> $DIR/checked_conversions.rs:55:13
+  --> $DIR/checked_conversions.rs:57:13
    |
 LL |     let _ = value <= u16::MAX as u32 && value as i32 == 5;
    |             ^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `u16::try_from(value).is_ok()`
 
-error: aborting due to 16 previous errors
+error: checked cast can be simplified
+  --> $DIR/checked_conversions.rs:92:13
+   |
+LL |     let _ = value <= (u32::MAX as i64) && value >= 0;
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `u32::try_from(value).is_ok()`
+
+error: aborting due to 17 previous errors
 
diff --git a/src/tools/clippy/tests/ui/cloned_instead_of_copied.fixed b/src/tools/clippy/tests/ui/cloned_instead_of_copied.fixed
index 4eb999e18e64..42ed232d1001 100644
--- a/src/tools/clippy/tests/ui/cloned_instead_of_copied.fixed
+++ b/src/tools/clippy/tests/ui/cloned_instead_of_copied.fixed
@@ -1,5 +1,8 @@
 // run-rustfix
+
+#![feature(custom_inner_attributes)]
 #![warn(clippy::cloned_instead_of_copied)]
+#![allow(unused)]
 
 fn main() {
     // yay
@@ -13,3 +16,24 @@ fn main() {
     let _ = [String::new()].iter().cloned();
     let _ = Some(&String::new()).cloned();
 }
+
+fn msrv_1_34() {
+    #![clippy::msrv = "1.34"]
+
+    let _ = [1].iter().cloned();
+    let _ = Some(&1).cloned();
+}
+
+fn msrv_1_35() {
+    #![clippy::msrv = "1.35"]
+
+    let _ = [1].iter().cloned();
+    let _ = Some(&1).copied(); // Option::copied needs 1.35
+}
+
+fn msrv_1_36() {
+    #![clippy::msrv = "1.36"]
+
+    let _ = [1].iter().copied(); // Iterator::copied needs 1.36
+    let _ = Some(&1).copied();
+}
diff --git a/src/tools/clippy/tests/ui/cloned_instead_of_copied.rs b/src/tools/clippy/tests/ui/cloned_instead_of_copied.rs
index 894496c0ebbb..471bd9654cc1 100644
--- a/src/tools/clippy/tests/ui/cloned_instead_of_copied.rs
+++ b/src/tools/clippy/tests/ui/cloned_instead_of_copied.rs
@@ -1,5 +1,8 @@
 // run-rustfix
+
+#![feature(custom_inner_attributes)]
 #![warn(clippy::cloned_instead_of_copied)]
+#![allow(unused)]
 
 fn main() {
     // yay
@@ -13,3 +16,24 @@ fn main() {
     let _ = [String::new()].iter().cloned();
     let _ = Some(&String::new()).cloned();
 }
+
+fn msrv_1_34() {
+    #![clippy::msrv = "1.34"]
+
+    let _ = [1].iter().cloned();
+    let _ = Some(&1).cloned();
+}
+
+fn msrv_1_35() {
+    #![clippy::msrv = "1.35"]
+
+    let _ = [1].iter().cloned();
+    let _ = Some(&1).cloned(); // Option::copied needs 1.35
+}
+
+fn msrv_1_36() {
+    #![clippy::msrv = "1.36"]
+
+    let _ = [1].iter().cloned(); // Iterator::copied needs 1.36
+    let _ = Some(&1).cloned();
+}
diff --git a/src/tools/clippy/tests/ui/cloned_instead_of_copied.stderr b/src/tools/clippy/tests/ui/cloned_instead_of_copied.stderr
index e0707d321468..914c9a91e830 100644
--- a/src/tools/clippy/tests/ui/cloned_instead_of_copied.stderr
+++ b/src/tools/clippy/tests/ui/cloned_instead_of_copied.stderr
@@ -1,5 +1,5 @@
 error: used `cloned` where `copied` could be used instead
-  --> $DIR/cloned_instead_of_copied.rs:6:24
+  --> $DIR/cloned_instead_of_copied.rs:9:24
    |
 LL |     let _ = [1].iter().cloned();
    |                        ^^^^^^ help: try: `copied`
@@ -7,28 +7,46 @@ LL |     let _ = [1].iter().cloned();
    = note: `-D clippy::cloned-instead-of-copied` implied by `-D warnings`
 
 error: used `cloned` where `copied` could be used instead
-  --> $DIR/cloned_instead_of_copied.rs:7:31
+  --> $DIR/cloned_instead_of_copied.rs:10:31
    |
 LL |     let _ = vec!["hi"].iter().cloned();
    |                               ^^^^^^ help: try: `copied`
 
 error: used `cloned` where `copied` could be used instead
-  --> $DIR/cloned_instead_of_copied.rs:8:22
+  --> $DIR/cloned_instead_of_copied.rs:11:22
    |
 LL |     let _ = Some(&1).cloned();
    |                      ^^^^^^ help: try: `copied`
 
 error: used `cloned` where `copied` could be used instead
-  --> $DIR/cloned_instead_of_copied.rs:9:34
+  --> $DIR/cloned_instead_of_copied.rs:12:34
    |
 LL |     let _ = Box::new([1].iter()).cloned();
    |                                  ^^^^^^ help: try: `copied`
 
 error: used `cloned` where `copied` could be used instead
-  --> $DIR/cloned_instead_of_copied.rs:10:32
+  --> $DIR/cloned_instead_of_copied.rs:13:32
    |
 LL |     let _ = Box::new(Some(&1)).cloned();
    |                                ^^^^^^ help: try: `copied`
 
-error: aborting due to 5 previous errors
+error: used `cloned` where `copied` could be used instead
+  --> $DIR/cloned_instead_of_copied.rs:31:22
+   |
+LL |     let _ = Some(&1).cloned(); // Option::copied needs 1.35
+   |                      ^^^^^^ help: try: `copied`
+
+error: used `cloned` where `copied` could be used instead
+  --> $DIR/cloned_instead_of_copied.rs:37:24
+   |
+LL |     let _ = [1].iter().cloned(); // Iterator::copied needs 1.36
+   |                        ^^^^^^ help: try: `copied`
+
+error: used `cloned` where `copied` could be used instead
+  --> $DIR/cloned_instead_of_copied.rs:38:22
+   |
+LL |     let _ = Some(&1).cloned();
+   |                      ^^^^^^ help: try: `copied`
+
+error: aborting due to 8 previous errors
 
diff --git a/src/tools/clippy/tests/ui/collapsible_match.rs b/src/tools/clippy/tests/ui/collapsible_match.rs
index 7d53e08345d3..1d7a72846419 100644
--- a/src/tools/clippy/tests/ui/collapsible_match.rs
+++ b/src/tools/clippy/tests/ui/collapsible_match.rs
@@ -253,6 +253,27 @@ fn negative_cases(res_opt: Result<Option<u32>, String>, res_res: Result<Result<u
     };
 }
 
+pub enum Issue9647 {
+    A { a: Option<Option<u8>>, b: () },
+    B,
+}
+
+pub fn test_1(x: Issue9647) {
+    if let Issue9647::A { a, .. } = x {
+        if let Some(u) = a {
+            println!("{u:?}")
+        }
+    }
+}
+
+pub fn test_2(x: Issue9647) {
+    if let Issue9647::A { a: Some(a), .. } = x {
+        if let Some(u) = a {
+            println!("{u}")
+        }
+    }
+}
+
 fn make<T>() -> T {
     unimplemented!()
 }
diff --git a/src/tools/clippy/tests/ui/collapsible_match.stderr b/src/tools/clippy/tests/ui/collapsible_match.stderr
index 2580bef58091..0294be60b43f 100644
--- a/src/tools/clippy/tests/ui/collapsible_match.stderr
+++ b/src/tools/clippy/tests/ui/collapsible_match.stderr
@@ -175,5 +175,37 @@ LL |         Some(val) => match val {
 LL |             Some(n) => foo(n),
    |             ^^^^^^^ with this pattern
 
-error: aborting due to 10 previous errors
+error: this `if let` can be collapsed into the outer `if let`
+  --> $DIR/collapsible_match.rs:263:9
+   |
+LL | /         if let Some(u) = a {
+LL | |             println!("{u:?}")
+LL | |         }
+   | |_________^
+   |
+help: the outer pattern can be modified to include the inner pattern
+  --> $DIR/collapsible_match.rs:262:27
+   |
+LL |     if let Issue9647::A { a, .. } = x {
+   |                           ^ replace this binding
+LL |         if let Some(u) = a {
+   |                ^^^^^^^ with this pattern, prefixed by a:
+
+error: this `if let` can be collapsed into the outer `if let`
+  --> $DIR/collapsible_match.rs:271:9
+   |
+LL | /         if let Some(u) = a {
+LL | |             println!("{u}")
+LL | |         }
+   | |_________^
+   |
+help: the outer pattern can be modified to include the inner pattern
+  --> $DIR/collapsible_match.rs:270:35
+   |
+LL |     if let Issue9647::A { a: Some(a), .. } = x {
+   |                                   ^ replace this binding
+LL |         if let Some(u) = a {
+   |                ^^^^^^^ with this pattern
+
+error: aborting due to 12 previous errors
 
diff --git a/src/tools/clippy/tests/ui/crashes/ice-6250.stderr b/src/tools/clippy/tests/ui/crashes/ice-6250.stderr
index 878897c410cf..4506d1550bd4 100644
--- a/src/tools/clippy/tests/ui/crashes/ice-6250.stderr
+++ b/src/tools/clippy/tests/ui/crashes/ice-6250.stderr
@@ -23,6 +23,11 @@ error[E0308]: mismatched types
    |
 LL |         Some(reference) = cache.data.get(key) {
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `bool`, found `()`
+   |
+help: consider adding `let`
+   |
+LL |         let Some(reference) = cache.data.get(key) {
+   |         +++
 
 error: aborting due to 3 previous errors
 
diff --git a/src/tools/clippy/tests/ui/crashes/ice-9625.rs b/src/tools/clippy/tests/ui/crashes/ice-9625.rs
new file mode 100644
index 000000000000..a765882b5d81
--- /dev/null
+++ b/src/tools/clippy/tests/ui/crashes/ice-9625.rs
@@ -0,0 +1,4 @@
+fn main() {
+    let x = &1;
+    let _ = &1 < x && x < &10;
+}
diff --git a/src/tools/clippy/tests/ui/default_numeric_fallback_f64.fixed b/src/tools/clippy/tests/ui/default_numeric_fallback_f64.fixed
index a28bff76755b..a370ccc76962 100644
--- a/src/tools/clippy/tests/ui/default_numeric_fallback_f64.fixed
+++ b/src/tools/clippy/tests/ui/default_numeric_fallback_f64.fixed
@@ -33,6 +33,7 @@ mod basic_expr {
         let x: [f64; 3] = [1., 2., 3.];
         let x: (f64, f64) = if true { (1., 2.) } else { (3., 4.) };
         let x: _ = 1.;
+        const X: f32 = 1.;
     }
 }
 
@@ -59,6 +60,14 @@ mod nested_local {
             // Should NOT lint this because this literal is bound to `_` of outer `Local`.
             2.
         };
+
+        const X: f32 = {
+            // Should lint this because this literal is not bound to any types.
+            let y = 1.0_f64;
+
+            // Should NOT lint this because this literal is bound to `_` of outer `Local`.
+            1.
+        };
     }
 }
 
diff --git a/src/tools/clippy/tests/ui/default_numeric_fallback_f64.rs b/src/tools/clippy/tests/ui/default_numeric_fallback_f64.rs
index b48435cc7b28..2476fe95141d 100644
--- a/src/tools/clippy/tests/ui/default_numeric_fallback_f64.rs
+++ b/src/tools/clippy/tests/ui/default_numeric_fallback_f64.rs
@@ -33,6 +33,7 @@ mod basic_expr {
         let x: [f64; 3] = [1., 2., 3.];
         let x: (f64, f64) = if true { (1., 2.) } else { (3., 4.) };
         let x: _ = 1.;
+        const X: f32 = 1.;
     }
 }
 
@@ -59,6 +60,14 @@ mod nested_local {
             // Should NOT lint this because this literal is bound to `_` of outer `Local`.
             2.
         };
+
+        const X: f32 = {
+            // Should lint this because this literal is not bound to any types.
+            let y = 1.;
+
+            // Should NOT lint this because this literal is bound to `_` of outer `Local`.
+            1.
+        };
     }
 }
 
diff --git a/src/tools/clippy/tests/ui/default_numeric_fallback_f64.stderr b/src/tools/clippy/tests/ui/default_numeric_fallback_f64.stderr
index f8b6c7746edb..5df2f642388d 100644
--- a/src/tools/clippy/tests/ui/default_numeric_fallback_f64.stderr
+++ b/src/tools/clippy/tests/ui/default_numeric_fallback_f64.stderr
@@ -61,79 +61,85 @@ LL |             _ => 1.,
    |                  ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_f64.rs:43:21
+  --> $DIR/default_numeric_fallback_f64.rs:44:21
    |
 LL |             let y = 1.;
    |                     ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_f64.rs:51:21
+  --> $DIR/default_numeric_fallback_f64.rs:52:21
    |
 LL |             let y = 1.;
    |                     ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_f64.rs:57:21
+  --> $DIR/default_numeric_fallback_f64.rs:58:21
    |
 LL |             let y = 1.;
    |                     ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_f64.rs:69:9
+  --> $DIR/default_numeric_fallback_f64.rs:66:21
+   |
+LL |             let y = 1.;
+   |                     ^^ help: consider adding suffix: `1.0_f64`
+
+error: default numeric fallback might occur
+  --> $DIR/default_numeric_fallback_f64.rs:78:9
    |
 LL |         1.
    |         ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_f64.rs:75:27
+  --> $DIR/default_numeric_fallback_f64.rs:84:27
    |
 LL |         let f = || -> _ { 1. };
    |                           ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_f64.rs:79:29
+  --> $DIR/default_numeric_fallback_f64.rs:88:29
    |
 LL |         let f = || -> f64 { 1. };
    |                             ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_f64.rs:93:21
+  --> $DIR/default_numeric_fallback_f64.rs:102:21
    |
 LL |         generic_arg(1.);
    |                     ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_f64.rs:96:32
+  --> $DIR/default_numeric_fallback_f64.rs:105:32
    |
 LL |         let x: _ = generic_arg(1.);
    |                                ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_f64.rs:114:28
+  --> $DIR/default_numeric_fallback_f64.rs:123:28
    |
 LL |         GenericStruct { x: 1. };
    |                            ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_f64.rs:117:36
+  --> $DIR/default_numeric_fallback_f64.rs:126:36
    |
 LL |         let _ = GenericStruct { x: 1. };
    |                                    ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_f64.rs:135:24
+  --> $DIR/default_numeric_fallback_f64.rs:144:24
    |
 LL |         GenericEnum::X(1.);
    |                        ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_f64.rs:155:23
+  --> $DIR/default_numeric_fallback_f64.rs:164:23
    |
 LL |         s.generic_arg(1.);
    |                       ^^ help: consider adding suffix: `1.0_f64`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_f64.rs:162:21
+  --> $DIR/default_numeric_fallback_f64.rs:171:21
    |
 LL |             let x = 22.;
    |                     ^^^ help: consider adding suffix: `22.0_f64`
@@ -143,5 +149,5 @@ LL |         internal_macro!();
    |
    = note: this error originates in the macro `internal_macro` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: aborting due to 23 previous errors
+error: aborting due to 24 previous errors
 
diff --git a/src/tools/clippy/tests/ui/default_numeric_fallback_i32.fixed b/src/tools/clippy/tests/ui/default_numeric_fallback_i32.fixed
index 55451cf2f7d0..3f4994f0453b 100644
--- a/src/tools/clippy/tests/ui/default_numeric_fallback_i32.fixed
+++ b/src/tools/clippy/tests/ui/default_numeric_fallback_i32.fixed
@@ -33,6 +33,8 @@ mod basic_expr {
         let x: [i32; 3] = [1, 2, 3];
         let x: (i32, i32) = if true { (1, 2) } else { (3, 4) };
         let x: _ = 1;
+        let x: u64 = 1;
+        const CONST_X: i8 = 1;
     }
 }
 
@@ -59,6 +61,14 @@ mod nested_local {
             // Should NOT lint this because this literal is bound to `_` of outer `Local`.
             2
         };
+
+        const CONST_X: i32 = {
+            // Should lint this because this literal is not bound to any types.
+            let y = 1_i32;
+
+            // Should NOT lint this because this literal is bound to `_` of outer `Local`.
+            1
+        };
     }
 }
 
diff --git a/src/tools/clippy/tests/ui/default_numeric_fallback_i32.rs b/src/tools/clippy/tests/ui/default_numeric_fallback_i32.rs
index 62d72f2febaa..2df0e09787f9 100644
--- a/src/tools/clippy/tests/ui/default_numeric_fallback_i32.rs
+++ b/src/tools/clippy/tests/ui/default_numeric_fallback_i32.rs
@@ -33,6 +33,8 @@ mod basic_expr {
         let x: [i32; 3] = [1, 2, 3];
         let x: (i32, i32) = if true { (1, 2) } else { (3, 4) };
         let x: _ = 1;
+        let x: u64 = 1;
+        const CONST_X: i8 = 1;
     }
 }
 
@@ -59,6 +61,14 @@ mod nested_local {
             // Should NOT lint this because this literal is bound to `_` of outer `Local`.
             2
         };
+
+        const CONST_X: i32 = {
+            // Should lint this because this literal is not bound to any types.
+            let y = 1;
+
+            // Should NOT lint this because this literal is bound to `_` of outer `Local`.
+            1
+        };
     }
 }
 
diff --git a/src/tools/clippy/tests/ui/default_numeric_fallback_i32.stderr b/src/tools/clippy/tests/ui/default_numeric_fallback_i32.stderr
index f7c5e724c403..6f219c3fc2b0 100644
--- a/src/tools/clippy/tests/ui/default_numeric_fallback_i32.stderr
+++ b/src/tools/clippy/tests/ui/default_numeric_fallback_i32.stderr
@@ -73,79 +73,85 @@ LL |             _ => 2,
    |                  ^ help: consider adding suffix: `2_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_i32.rs:43:21
+  --> $DIR/default_numeric_fallback_i32.rs:45:21
    |
 LL |             let y = 1;
    |                     ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_i32.rs:51:21
+  --> $DIR/default_numeric_fallback_i32.rs:53:21
    |
 LL |             let y = 1;
    |                     ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_i32.rs:57:21
+  --> $DIR/default_numeric_fallback_i32.rs:59:21
    |
 LL |             let y = 1;
    |                     ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_i32.rs:69:9
+  --> $DIR/default_numeric_fallback_i32.rs:67:21
+   |
+LL |             let y = 1;
+   |                     ^ help: consider adding suffix: `1_i32`
+
+error: default numeric fallback might occur
+  --> $DIR/default_numeric_fallback_i32.rs:79:9
    |
 LL |         1
    |         ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_i32.rs:75:27
+  --> $DIR/default_numeric_fallback_i32.rs:85:27
    |
 LL |         let f = || -> _ { 1 };
    |                           ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_i32.rs:79:29
+  --> $DIR/default_numeric_fallback_i32.rs:89:29
    |
 LL |         let f = || -> i32 { 1 };
    |                             ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_i32.rs:93:21
+  --> $DIR/default_numeric_fallback_i32.rs:103:21
    |
 LL |         generic_arg(1);
    |                     ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_i32.rs:96:32
+  --> $DIR/default_numeric_fallback_i32.rs:106:32
    |
 LL |         let x: _ = generic_arg(1);
    |                                ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_i32.rs:114:28
+  --> $DIR/default_numeric_fallback_i32.rs:124:28
    |
 LL |         GenericStruct { x: 1 };
    |                            ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_i32.rs:117:36
+  --> $DIR/default_numeric_fallback_i32.rs:127:36
    |
 LL |         let _ = GenericStruct { x: 1 };
    |                                    ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_i32.rs:135:24
+  --> $DIR/default_numeric_fallback_i32.rs:145:24
    |
 LL |         GenericEnum::X(1);
    |                        ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_i32.rs:155:23
+  --> $DIR/default_numeric_fallback_i32.rs:165:23
    |
 LL |         s.generic_arg(1);
    |                       ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback_i32.rs:162:21
+  --> $DIR/default_numeric_fallback_i32.rs:172:21
    |
 LL |             let x = 22;
    |                     ^^ help: consider adding suffix: `22_i32`
@@ -155,5 +161,5 @@ LL |         internal_macro!();
    |
    = note: this error originates in the macro `internal_macro` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: aborting due to 25 previous errors
+error: aborting due to 26 previous errors
 
diff --git a/src/tools/clippy/tests/ui/err_expect.fixed b/src/tools/clippy/tests/ui/err_expect.fixed
index 7e18d70bae40..3bac738acd65 100644
--- a/src/tools/clippy/tests/ui/err_expect.fixed
+++ b/src/tools/clippy/tests/ui/err_expect.fixed
@@ -1,5 +1,8 @@
 // run-rustfix
 
+#![feature(custom_inner_attributes)]
+#![allow(unused)]
+
 struct MyTypeNonDebug;
 
 #[derive(Debug)]
@@ -12,3 +15,17 @@ fn main() {
     let test_non_debug: Result<MyTypeNonDebug, u32> = Ok(MyTypeNonDebug);
     test_non_debug.err().expect("Testing non debug type");
 }
+
+fn msrv_1_16() {
+    #![clippy::msrv = "1.16"]
+
+    let x: Result<u32, &str> = Ok(16);
+    x.err().expect("16");
+}
+
+fn msrv_1_17() {
+    #![clippy::msrv = "1.17"]
+
+    let x: Result<u32, &str> = Ok(17);
+    x.expect_err("17");
+}
diff --git a/src/tools/clippy/tests/ui/err_expect.rs b/src/tools/clippy/tests/ui/err_expect.rs
index bf8c3c9fb8c9..6e7c47d9ad3c 100644
--- a/src/tools/clippy/tests/ui/err_expect.rs
+++ b/src/tools/clippy/tests/ui/err_expect.rs
@@ -1,5 +1,8 @@
 // run-rustfix
 
+#![feature(custom_inner_attributes)]
+#![allow(unused)]
+
 struct MyTypeNonDebug;
 
 #[derive(Debug)]
@@ -12,3 +15,17 @@ fn main() {
     let test_non_debug: Result<MyTypeNonDebug, u32> = Ok(MyTypeNonDebug);
     test_non_debug.err().expect("Testing non debug type");
 }
+
+fn msrv_1_16() {
+    #![clippy::msrv = "1.16"]
+
+    let x: Result<u32, &str> = Ok(16);
+    x.err().expect("16");
+}
+
+fn msrv_1_17() {
+    #![clippy::msrv = "1.17"]
+
+    let x: Result<u32, &str> = Ok(17);
+    x.err().expect("17");
+}
diff --git a/src/tools/clippy/tests/ui/err_expect.stderr b/src/tools/clippy/tests/ui/err_expect.stderr
index ffd97e00a5c0..91a6cf8de65f 100644
--- a/src/tools/clippy/tests/ui/err_expect.stderr
+++ b/src/tools/clippy/tests/ui/err_expect.stderr
@@ -1,10 +1,16 @@
 error: called `.err().expect()` on a `Result` value
-  --> $DIR/err_expect.rs:10:16
+  --> $DIR/err_expect.rs:13:16
    |
 LL |     test_debug.err().expect("Testing debug type");
    |                ^^^^^^^^^^^^ help: try: `expect_err`
    |
    = note: `-D clippy::err-expect` implied by `-D warnings`
 
-error: aborting due to previous error
+error: called `.err().expect()` on a `Result` value
+  --> $DIR/err_expect.rs:30:7
+   |
+LL |     x.err().expect("17");
+   |       ^^^^^^^^^^^^ help: try: `expect_err`
+
+error: aborting due to 2 previous errors
 
diff --git a/src/tools/clippy/tests/ui/filter_map_next_fixable.fixed b/src/tools/clippy/tests/ui/filter_map_next_fixable.fixed
index c3992d7e92cf..41828ddd7acd 100644
--- a/src/tools/clippy/tests/ui/filter_map_next_fixable.fixed
+++ b/src/tools/clippy/tests/ui/filter_map_next_fixable.fixed
@@ -1,6 +1,8 @@
 // run-rustfix
 
+#![feature(custom_inner_attributes)]
 #![warn(clippy::all, clippy::pedantic)]
+#![allow(unused)]
 
 fn main() {
     let a = ["1", "lol", "3", "NaN", "5"];
@@ -8,3 +10,17 @@ fn main() {
     let element: Option<i32> = a.iter().find_map(|s| s.parse().ok());
     assert_eq!(element, Some(1));
 }
+
+fn msrv_1_29() {
+    #![clippy::msrv = "1.29"]
+
+    let a = ["1", "lol", "3", "NaN", "5"];
+    let _: Option<i32> = a.iter().filter_map(|s| s.parse().ok()).next();
+}
+
+fn msrv_1_30() {
+    #![clippy::msrv = "1.30"]
+
+    let a = ["1", "lol", "3", "NaN", "5"];
+    let _: Option<i32> = a.iter().find_map(|s| s.parse().ok());
+}
diff --git a/src/tools/clippy/tests/ui/filter_map_next_fixable.rs b/src/tools/clippy/tests/ui/filter_map_next_fixable.rs
index 447219a96839..be492a81b45e 100644
--- a/src/tools/clippy/tests/ui/filter_map_next_fixable.rs
+++ b/src/tools/clippy/tests/ui/filter_map_next_fixable.rs
@@ -1,6 +1,8 @@
 // run-rustfix
 
+#![feature(custom_inner_attributes)]
 #![warn(clippy::all, clippy::pedantic)]
+#![allow(unused)]
 
 fn main() {
     let a = ["1", "lol", "3", "NaN", "5"];
@@ -8,3 +10,17 @@ fn main() {
     let element: Option<i32> = a.iter().filter_map(|s| s.parse().ok()).next();
     assert_eq!(element, Some(1));
 }
+
+fn msrv_1_29() {
+    #![clippy::msrv = "1.29"]
+
+    let a = ["1", "lol", "3", "NaN", "5"];
+    let _: Option<i32> = a.iter().filter_map(|s| s.parse().ok()).next();
+}
+
+fn msrv_1_30() {
+    #![clippy::msrv = "1.30"]
+
+    let a = ["1", "lol", "3", "NaN", "5"];
+    let _: Option<i32> = a.iter().filter_map(|s| s.parse().ok()).next();
+}
diff --git a/src/tools/clippy/tests/ui/filter_map_next_fixable.stderr b/src/tools/clippy/tests/ui/filter_map_next_fixable.stderr
index 3bb062ffd7a3..e789efeabd55 100644
--- a/src/tools/clippy/tests/ui/filter_map_next_fixable.stderr
+++ b/src/tools/clippy/tests/ui/filter_map_next_fixable.stderr
@@ -1,10 +1,16 @@
 error: called `filter_map(..).next()` on an `Iterator`. This is more succinctly expressed by calling `.find_map(..)` instead
-  --> $DIR/filter_map_next_fixable.rs:8:32
+  --> $DIR/filter_map_next_fixable.rs:10:32
    |
 LL |     let element: Option<i32> = a.iter().filter_map(|s| s.parse().ok()).next();
    |                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `a.iter().find_map(|s| s.parse().ok())`
    |
    = note: `-D clippy::filter-map-next` implied by `-D warnings`
 
-error: aborting due to previous error
+error: called `filter_map(..).next()` on an `Iterator`. This is more succinctly expressed by calling `.find_map(..)` instead
+  --> $DIR/filter_map_next_fixable.rs:25:26
+   |
+LL |     let _: Option<i32> = a.iter().filter_map(|s| s.parse().ok()).next();
+   |                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `a.iter().find_map(|s| s.parse().ok())`
+
+error: aborting due to 2 previous errors
 
diff --git a/src/tools/clippy/tests/ui/format_args.fixed b/src/tools/clippy/tests/ui/format_args.fixed
index 24cf0847dd58..825e122be5a5 100644
--- a/src/tools/clippy/tests/ui/format_args.fixed
+++ b/src/tools/clippy/tests/ui/format_args.fixed
@@ -3,6 +3,7 @@
 #![allow(unused)]
 #![allow(
     clippy::assertions_on_constants,
+    clippy::double_parens,
     clippy::eq_op,
     clippy::print_literal,
     clippy::uninlined_format_args
@@ -114,6 +115,8 @@ fn main() {
     println!("error: something failed at {}", my_other_macro!());
     // https://github.com/rust-lang/rust-clippy/issues/7903
     println!("{foo}{foo:?}", foo = "foo".to_string());
+    print!("{}", (Location::caller()));
+    print!("{}", ((Location::caller())));
 }
 
 fn issue8643(vendor_id: usize, product_id: usize, name: &str) {
diff --git a/src/tools/clippy/tests/ui/format_args.rs b/src/tools/clippy/tests/ui/format_args.rs
index 753babf0afdc..a41e53389e52 100644
--- a/src/tools/clippy/tests/ui/format_args.rs
+++ b/src/tools/clippy/tests/ui/format_args.rs
@@ -3,6 +3,7 @@
 #![allow(unused)]
 #![allow(
     clippy::assertions_on_constants,
+    clippy::double_parens,
     clippy::eq_op,
     clippy::print_literal,
     clippy::uninlined_format_args
@@ -114,6 +115,8 @@ fn main() {
     println!("error: something failed at {}", my_other_macro!());
     // https://github.com/rust-lang/rust-clippy/issues/7903
     println!("{foo}{foo:?}", foo = "foo".to_string());
+    print!("{}", (Location::caller().to_string()));
+    print!("{}", ((Location::caller()).to_string()));
 }
 
 fn issue8643(vendor_id: usize, product_id: usize, name: &str) {
diff --git a/src/tools/clippy/tests/ui/format_args.stderr b/src/tools/clippy/tests/ui/format_args.stderr
index 68b0bb9e089e..f1832b970198 100644
--- a/src/tools/clippy/tests/ui/format_args.stderr
+++ b/src/tools/clippy/tests/ui/format_args.stderr
@@ -1,5 +1,5 @@
 error: `to_string` applied to a type that implements `Display` in `format!` args
-  --> $DIR/format_args.rs:76:72
+  --> $DIR/format_args.rs:77:72
    |
 LL |     let _ = format!("error: something failed at {}", Location::caller().to_string());
    |                                                                        ^^^^^^^^^^^^ help: remove this
@@ -7,136 +7,148 @@ LL |     let _ = format!("error: something failed at {}", Location::caller().to_
    = note: `-D clippy::to-string-in-format-args` implied by `-D warnings`
 
 error: `to_string` applied to a type that implements `Display` in `write!` args
-  --> $DIR/format_args.rs:80:27
+  --> $DIR/format_args.rs:81:27
    |
 LL |         Location::caller().to_string()
    |                           ^^^^^^^^^^^^ help: remove this
 
 error: `to_string` applied to a type that implements `Display` in `writeln!` args
-  --> $DIR/format_args.rs:85:27
+  --> $DIR/format_args.rs:86:27
    |
 LL |         Location::caller().to_string()
    |                           ^^^^^^^^^^^^ help: remove this
 
 error: `to_string` applied to a type that implements `Display` in `print!` args
-  --> $DIR/format_args.rs:87:63
+  --> $DIR/format_args.rs:88:63
    |
 LL |     print!("error: something failed at {}", Location::caller().to_string());
    |                                                               ^^^^^^^^^^^^ help: remove this
 
 error: `to_string` applied to a type that implements `Display` in `println!` args
-  --> $DIR/format_args.rs:88:65
+  --> $DIR/format_args.rs:89:65
    |
 LL |     println!("error: something failed at {}", Location::caller().to_string());
    |                                                                 ^^^^^^^^^^^^ help: remove this
 
 error: `to_string` applied to a type that implements `Display` in `eprint!` args
-  --> $DIR/format_args.rs:89:64
+  --> $DIR/format_args.rs:90:64
    |
 LL |     eprint!("error: something failed at {}", Location::caller().to_string());
    |                                                                ^^^^^^^^^^^^ help: remove this
 
 error: `to_string` applied to a type that implements `Display` in `eprintln!` args
-  --> $DIR/format_args.rs:90:66
+  --> $DIR/format_args.rs:91:66
    |
 LL |     eprintln!("error: something failed at {}", Location::caller().to_string());
    |                                                                  ^^^^^^^^^^^^ help: remove this
 
 error: `to_string` applied to a type that implements `Display` in `format_args!` args
-  --> $DIR/format_args.rs:91:77
+  --> $DIR/format_args.rs:92:77
    |
 LL |     let _ = format_args!("error: something failed at {}", Location::caller().to_string());
    |                                                                             ^^^^^^^^^^^^ help: remove this
 
 error: `to_string` applied to a type that implements `Display` in `assert!` args
-  --> $DIR/format_args.rs:92:70
+  --> $DIR/format_args.rs:93:70
    |
 LL |     assert!(true, "error: something failed at {}", Location::caller().to_string());
    |                                                                      ^^^^^^^^^^^^ help: remove this
 
 error: `to_string` applied to a type that implements `Display` in `assert_eq!` args
-  --> $DIR/format_args.rs:93:73
+  --> $DIR/format_args.rs:94:73
    |
 LL |     assert_eq!(0, 0, "error: something failed at {}", Location::caller().to_string());
    |                                                                         ^^^^^^^^^^^^ help: remove this
 
 error: `to_string` applied to a type that implements `Display` in `assert_ne!` args
-  --> $DIR/format_args.rs:94:73
+  --> $DIR/format_args.rs:95:73
    |
 LL |     assert_ne!(0, 0, "error: something failed at {}", Location::caller().to_string());
    |                                                                         ^^^^^^^^^^^^ help: remove this
 
 error: `to_string` applied to a type that implements `Display` in `panic!` args
-  --> $DIR/format_args.rs:95:63
+  --> $DIR/format_args.rs:96:63
    |
 LL |     panic!("error: something failed at {}", Location::caller().to_string());
    |                                                               ^^^^^^^^^^^^ help: remove this
 
 error: `to_string` applied to a type that implements `Display` in `println!` args
-  --> $DIR/format_args.rs:96:20
+  --> $DIR/format_args.rs:97:20
    |
 LL |     println!("{}", X(1).to_string());
    |                    ^^^^^^^^^^^^^^^^ help: use this: `*X(1)`
 
 error: `to_string` applied to a type that implements `Display` in `println!` args
-  --> $DIR/format_args.rs:97:20
+  --> $DIR/format_args.rs:98:20
    |
 LL |     println!("{}", Y(&X(1)).to_string());
    |                    ^^^^^^^^^^^^^^^^^^^^ help: use this: `***Y(&X(1))`
 
 error: `to_string` applied to a type that implements `Display` in `println!` args
-  --> $DIR/format_args.rs:98:24
+  --> $DIR/format_args.rs:99:24
    |
 LL |     println!("{}", Z(1).to_string());
    |                        ^^^^^^^^^^^^ help: remove this
 
 error: `to_string` applied to a type that implements `Display` in `println!` args
-  --> $DIR/format_args.rs:99:20
+  --> $DIR/format_args.rs:100:20
    |
 LL |     println!("{}", x.to_string());
    |                    ^^^^^^^^^^^^^ help: use this: `**x`
 
 error: `to_string` applied to a type that implements `Display` in `println!` args
-  --> $DIR/format_args.rs:100:20
+  --> $DIR/format_args.rs:101:20
    |
 LL |     println!("{}", x_ref.to_string());
    |                    ^^^^^^^^^^^^^^^^^ help: use this: `***x_ref`
 
 error: `to_string` applied to a type that implements `Display` in `println!` args
-  --> $DIR/format_args.rs:102:39
+  --> $DIR/format_args.rs:103:39
    |
 LL |     println!("{foo}{bar}", foo = "foo".to_string(), bar = "bar");
    |                                       ^^^^^^^^^^^^ help: remove this
 
 error: `to_string` applied to a type that implements `Display` in `println!` args
-  --> $DIR/format_args.rs:103:52
+  --> $DIR/format_args.rs:104:52
    |
 LL |     println!("{foo}{bar}", foo = "foo", bar = "bar".to_string());
    |                                                    ^^^^^^^^^^^^ help: remove this
 
 error: `to_string` applied to a type that implements `Display` in `println!` args
-  --> $DIR/format_args.rs:104:39
+  --> $DIR/format_args.rs:105:39
    |
 LL |     println!("{foo}{bar}", bar = "bar".to_string(), foo = "foo");
    |                                       ^^^^^^^^^^^^ help: remove this
 
 error: `to_string` applied to a type that implements `Display` in `println!` args
-  --> $DIR/format_args.rs:105:52
+  --> $DIR/format_args.rs:106:52
    |
 LL |     println!("{foo}{bar}", bar = "bar", foo = "foo".to_string());
    |                                                    ^^^^^^^^^^^^ help: remove this
 
+error: `to_string` applied to a type that implements `Display` in `print!` args
+  --> $DIR/format_args.rs:118:37
+   |
+LL |     print!("{}", (Location::caller().to_string()));
+   |                                     ^^^^^^^^^^^^ help: remove this
+
+error: `to_string` applied to a type that implements `Display` in `print!` args
+  --> $DIR/format_args.rs:119:39
+   |
+LL |     print!("{}", ((Location::caller()).to_string()));
+   |                                       ^^^^^^^^^^^^ help: remove this
+
 error: `to_string` applied to a type that implements `Display` in `format!` args
-  --> $DIR/format_args.rs:144:38
+  --> $DIR/format_args.rs:147:38
    |
 LL |         let x = format!("{} {}", a, b.to_string());
    |                                      ^^^^^^^^^^^^ help: remove this
 
 error: `to_string` applied to a type that implements `Display` in `println!` args
-  --> $DIR/format_args.rs:158:24
+  --> $DIR/format_args.rs:161:24
    |
 LL |         println!("{}", original[..10].to_string());
    |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use this: `&original[..10]`
 
-error: aborting due to 23 previous errors
+error: aborting due to 25 previous errors
 
diff --git a/src/tools/clippy/tests/ui/from_over_into.fixed b/src/tools/clippy/tests/ui/from_over_into.fixed
new file mode 100644
index 000000000000..1cf49ca45f49
--- /dev/null
+++ b/src/tools/clippy/tests/ui/from_over_into.fixed
@@ -0,0 +1,87 @@
+// run-rustfix
+
+#![feature(custom_inner_attributes)]
+#![warn(clippy::from_over_into)]
+#![allow(unused)]
+
+// this should throw an error
+struct StringWrapper(String);
+
+impl From<String> for StringWrapper {
+    fn from(val: String) -> Self {
+        StringWrapper(val)
+    }
+}
+
+struct SelfType(String);
+
+impl From<String> for SelfType {
+    fn from(val: String) -> Self {
+        SelfType(String::new())
+    }
+}
+
+#[derive(Default)]
+struct X;
+
+impl X {
+    const FOO: &'static str = "a";
+}
+
+struct SelfKeywords;
+
+impl From<X> for SelfKeywords {
+    fn from(val: X) -> Self {
+        let _ = X::default();
+        let _ = X::FOO;
+        let _: X = val;
+
+        SelfKeywords
+    }
+}
+
+struct ExplicitPaths(bool);
+
+impl core::convert::From<crate::ExplicitPaths> for bool {
+    fn from(mut val: crate::ExplicitPaths) -> Self {
+        let in_closure = || val.0;
+
+        val.0 = false;
+        val.0
+    }
+}
+
+// this is fine
+struct A(String);
+
+impl From<String> for A {
+    fn from(s: String) -> A {
+        A(s)
+    }
+}
+
+fn msrv_1_40() {
+    #![clippy::msrv = "1.40"]
+
+    struct FromOverInto<T>(Vec<T>);
+
+    impl<T> Into<FromOverInto<T>> for Vec<T> {
+        fn into(self) -> FromOverInto<T> {
+            FromOverInto(self)
+        }
+    }
+}
+
+fn msrv_1_41() {
+    #![clippy::msrv = "1.41"]
+
+    struct FromOverInto<T>(Vec<T>);
+
+    impl<T> From<Vec<T>> for FromOverInto<T> {
+        fn from(val: Vec<T>) -> Self {
+            FromOverInto(val)
+        }
+    }
+}
+
+fn main() {}
diff --git a/src/tools/clippy/tests/ui/from_over_into.rs b/src/tools/clippy/tests/ui/from_over_into.rs
index 292d0924fb17..d30f3c3fc925 100644
--- a/src/tools/clippy/tests/ui/from_over_into.rs
+++ b/src/tools/clippy/tests/ui/from_over_into.rs
@@ -1,4 +1,8 @@
+// run-rustfix
+
+#![feature(custom_inner_attributes)]
 #![warn(clippy::from_over_into)]
+#![allow(unused)]
 
 // this should throw an error
 struct StringWrapper(String);
@@ -9,6 +13,44 @@ impl Into<StringWrapper> for String {
     }
 }
 
+struct SelfType(String);
+
+impl Into<SelfType> for String {
+    fn into(self) -> SelfType {
+        SelfType(Self::new())
+    }
+}
+
+#[derive(Default)]
+struct X;
+
+impl X {
+    const FOO: &'static str = "a";
+}
+
+struct SelfKeywords;
+
+impl Into<SelfKeywords> for X {
+    fn into(self) -> SelfKeywords {
+        let _ = Self::default();
+        let _ = Self::FOO;
+        let _: Self = self;
+
+        SelfKeywords
+    }
+}
+
+struct ExplicitPaths(bool);
+
+impl core::convert::Into<bool> for crate::ExplicitPaths {
+    fn into(mut self) -> bool {
+        let in_closure = || self.0;
+
+        self.0 = false;
+        self.0
+    }
+}
+
 // this is fine
 struct A(String);
 
@@ -18,4 +60,28 @@ impl From<String> for A {
     }
 }
 
+fn msrv_1_40() {
+    #![clippy::msrv = "1.40"]
+
+    struct FromOverInto<T>(Vec<T>);
+
+    impl<T> Into<FromOverInto<T>> for Vec<T> {
+        fn into(self) -> FromOverInto<T> {
+            FromOverInto(self)
+        }
+    }
+}
+
+fn msrv_1_41() {
+    #![clippy::msrv = "1.41"]
+
+    struct FromOverInto<T>(Vec<T>);
+
+    impl<T> Into<FromOverInto<T>> for Vec<T> {
+        fn into(self) -> FromOverInto<T> {
+            FromOverInto(self)
+        }
+    }
+}
+
 fn main() {}
diff --git a/src/tools/clippy/tests/ui/from_over_into.stderr b/src/tools/clippy/tests/ui/from_over_into.stderr
index 469adadd2196..9c2a7c04c364 100644
--- a/src/tools/clippy/tests/ui/from_over_into.stderr
+++ b/src/tools/clippy/tests/ui/from_over_into.stderr
@@ -1,11 +1,75 @@
 error: an implementation of `From` is preferred since it gives you `Into<_>` for free where the reverse isn't true
-  --> $DIR/from_over_into.rs:6:1
+  --> $DIR/from_over_into.rs:10:1
    |
 LL | impl Into<StringWrapper> for String {
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: consider to implement `From<std::string::String>` instead
    = note: `-D clippy::from-over-into` implied by `-D warnings`
+help: replace the `Into` implentation with `From<std::string::String>`
+   |
+LL ~ impl From<String> for StringWrapper {
+LL ~     fn from(val: String) -> Self {
+LL ~         StringWrapper(val)
+   |
 
-error: aborting due to previous error
+error: an implementation of `From` is preferred since it gives you `Into<_>` for free where the reverse isn't true
+  --> $DIR/from_over_into.rs:18:1
+   |
+LL | impl Into<SelfType> for String {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: replace the `Into` implentation with `From<std::string::String>`
+   |
+LL ~ impl From<String> for SelfType {
+LL ~     fn from(val: String) -> Self {
+LL ~         SelfType(String::new())
+   |
+
+error: an implementation of `From` is preferred since it gives you `Into<_>` for free where the reverse isn't true
+  --> $DIR/from_over_into.rs:33:1
+   |
+LL | impl Into<SelfKeywords> for X {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: replace the `Into` implentation with `From<X>`
+   |
+LL ~ impl From<X> for SelfKeywords {
+LL ~     fn from(val: X) -> Self {
+LL ~         let _ = X::default();
+LL ~         let _ = X::FOO;
+LL ~         let _: X = val;
+   |
+
+error: an implementation of `From` is preferred since it gives you `Into<_>` for free where the reverse isn't true
+  --> $DIR/from_over_into.rs:45:1
+   |
+LL | impl core::convert::Into<bool> for crate::ExplicitPaths {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = help: `impl From<Local> for Foreign` is allowed by the orphan rules, for more information see
+           https://doc.rust-lang.org/reference/items/implementations.html#trait-implementation-coherence
+help: replace the `Into` implentation with `From<ExplicitPaths>`
+   |
+LL ~ impl core::convert::From<crate::ExplicitPaths> for bool {
+LL ~     fn from(mut val: crate::ExplicitPaths) -> Self {
+LL ~         let in_closure = || val.0;
+LL | 
+LL ~         val.0 = false;
+LL ~         val.0
+   |
+
+error: an implementation of `From` is preferred since it gives you `Into<_>` for free where the reverse isn't true
+  --> $DIR/from_over_into.rs:80:5
+   |
+LL |     impl<T> Into<FromOverInto<T>> for Vec<T> {
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: replace the `Into` implentation with `From<std::vec::Vec<T>>`
+   |
+LL ~     impl<T> From<Vec<T>> for FromOverInto<T> {
+LL ~         fn from(val: Vec<T>) -> Self {
+LL ~             FromOverInto(val)
+   |
+
+error: aborting due to 5 previous errors
 
diff --git a/src/tools/clippy/tests/ui/from_over_into_unfixable.rs b/src/tools/clippy/tests/ui/from_over_into_unfixable.rs
new file mode 100644
index 000000000000..3b280b7488ae
--- /dev/null
+++ b/src/tools/clippy/tests/ui/from_over_into_unfixable.rs
@@ -0,0 +1,35 @@
+#![warn(clippy::from_over_into)]
+
+struct InMacro(String);
+
+macro_rules! in_macro {
+    ($e:ident) => {
+        $e
+    };
+}
+
+impl Into<InMacro> for String {
+    fn into(self) -> InMacro {
+        InMacro(in_macro!(self))
+    }
+}
+
+struct WeirdUpperSelf;
+
+impl Into<WeirdUpperSelf> for &'static [u8] {
+    fn into(self) -> WeirdUpperSelf {
+        let _ = Self::default();
+        WeirdUpperSelf
+    }
+}
+
+struct ContainsVal;
+
+impl Into<u8> for ContainsVal {
+    fn into(self) -> u8 {
+        let val = 1;
+        val + 1
+    }
+}
+
+fn main() {}
diff --git a/src/tools/clippy/tests/ui/from_over_into_unfixable.stderr b/src/tools/clippy/tests/ui/from_over_into_unfixable.stderr
new file mode 100644
index 000000000000..6f6ce351921b
--- /dev/null
+++ b/src/tools/clippy/tests/ui/from_over_into_unfixable.stderr
@@ -0,0 +1,29 @@
+error: an implementation of `From` is preferred since it gives you `Into<_>` for free where the reverse isn't true
+  --> $DIR/from_over_into_unfixable.rs:11:1
+   |
+LL | impl Into<InMacro> for String {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = help: replace the `Into` implentation with `From<std::string::String>`
+   = note: `-D clippy::from-over-into` implied by `-D warnings`
+
+error: an implementation of `From` is preferred since it gives you `Into<_>` for free where the reverse isn't true
+  --> $DIR/from_over_into_unfixable.rs:19:1
+   |
+LL | impl Into<WeirdUpperSelf> for &'static [u8] {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = help: replace the `Into` implentation with `From<&'static [u8]>`
+
+error: an implementation of `From` is preferred since it gives you `Into<_>` for free where the reverse isn't true
+  --> $DIR/from_over_into_unfixable.rs:28:1
+   |
+LL | impl Into<u8> for ContainsVal {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = help: `impl From<Local> for Foreign` is allowed by the orphan rules, for more information see
+           https://doc.rust-lang.org/reference/items/implementations.html#trait-implementation-coherence
+   = help: replace the `Into` implentation with `From<ContainsVal>`
+
+error: aborting due to 3 previous errors
+
diff --git a/src/tools/clippy/tests/ui/implicit_saturating_sub.fixed b/src/tools/clippy/tests/ui/implicit_saturating_sub.fixed
index e6f57e9267ea..93df81b1a7ff 100644
--- a/src/tools/clippy/tests/ui/implicit_saturating_sub.fixed
+++ b/src/tools/clippy/tests/ui/implicit_saturating_sub.fixed
@@ -2,6 +2,21 @@
 #![allow(unused_assignments, unused_mut, clippy::assign_op_pattern)]
 #![warn(clippy::implicit_saturating_sub)]
 
+use std::cmp::PartialEq;
+use std::ops::SubAssign;
+// Mock type
+struct Mock;
+
+impl PartialEq<u32> for Mock {
+    fn eq(&self, _: &u32) -> bool {
+        true
+    }
+}
+
+impl SubAssign<u32> for Mock {
+    fn sub_assign(&mut self, _: u32) {}
+}
+
 fn main() {
     // Tests for unsigned integers
 
@@ -165,4 +180,39 @@ fn main() {
     } else {
         println!("side effect");
     }
+
+    // Extended tests
+    let mut m = Mock;
+    let mut u_32 = 3000;
+    let a = 200;
+    let mut _b = 8;
+
+    if m != 0 {
+        m -= 1;
+    }
+
+    if a > 0 {
+        _b -= 1;
+    }
+
+    if 0 > a {
+        _b -= 1;
+    }
+
+    if u_32 > 0 {
+        u_32 -= 1;
+    } else {
+        println!("don't lint this");
+    }
+
+    if u_32 > 0 {
+        println!("don't lint this");
+        u_32 -= 1;
+    }
+
+    if u_32 > 42 {
+        println!("brace yourself!");
+    } else if u_32 > 0 {
+        u_32 -= 1;
+    }
 }
diff --git a/src/tools/clippy/tests/ui/implicit_saturating_sub.rs b/src/tools/clippy/tests/ui/implicit_saturating_sub.rs
index 8bb28d149c62..8340bc8264d5 100644
--- a/src/tools/clippy/tests/ui/implicit_saturating_sub.rs
+++ b/src/tools/clippy/tests/ui/implicit_saturating_sub.rs
@@ -2,6 +2,21 @@
 #![allow(unused_assignments, unused_mut, clippy::assign_op_pattern)]
 #![warn(clippy::implicit_saturating_sub)]
 
+use std::cmp::PartialEq;
+use std::ops::SubAssign;
+// Mock type
+struct Mock;
+
+impl PartialEq<u32> for Mock {
+    fn eq(&self, _: &u32) -> bool {
+        true
+    }
+}
+
+impl SubAssign<u32> for Mock {
+    fn sub_assign(&mut self, _: u32) {}
+}
+
 fn main() {
     // Tests for unsigned integers
 
@@ -211,4 +226,39 @@ fn main() {
     } else {
         println!("side effect");
     }
+
+    // Extended tests
+    let mut m = Mock;
+    let mut u_32 = 3000;
+    let a = 200;
+    let mut _b = 8;
+
+    if m != 0 {
+        m -= 1;
+    }
+
+    if a > 0 {
+        _b -= 1;
+    }
+
+    if 0 > a {
+        _b -= 1;
+    }
+
+    if u_32 > 0 {
+        u_32 -= 1;
+    } else {
+        println!("don't lint this");
+    }
+
+    if u_32 > 0 {
+        println!("don't lint this");
+        u_32 -= 1;
+    }
+
+    if u_32 > 42 {
+        println!("brace yourself!");
+    } else if u_32 > 0 {
+        u_32 -= 1;
+    }
 }
diff --git a/src/tools/clippy/tests/ui/implicit_saturating_sub.stderr b/src/tools/clippy/tests/ui/implicit_saturating_sub.stderr
index 5bb9a606422a..5e589d931e43 100644
--- a/src/tools/clippy/tests/ui/implicit_saturating_sub.stderr
+++ b/src/tools/clippy/tests/ui/implicit_saturating_sub.stderr
@@ -1,5 +1,5 @@
 error: implicitly performing saturating subtraction
-  --> $DIR/implicit_saturating_sub.rs:13:5
+  --> $DIR/implicit_saturating_sub.rs:28:5
    |
 LL | /     if u_8 > 0 {
 LL | |         u_8 = u_8 - 1;
@@ -9,7 +9,7 @@ LL | |     }
    = note: `-D clippy::implicit-saturating-sub` implied by `-D warnings`
 
 error: implicitly performing saturating subtraction
-  --> $DIR/implicit_saturating_sub.rs:20:13
+  --> $DIR/implicit_saturating_sub.rs:35:13
    |
 LL | /             if u_8 > 0 {
 LL | |                 u_8 -= 1;
@@ -17,7 +17,7 @@ LL | |             }
    | |_____________^ help: try: `u_8 = u_8.saturating_sub(1);`
 
 error: implicitly performing saturating subtraction
-  --> $DIR/implicit_saturating_sub.rs:34:5
+  --> $DIR/implicit_saturating_sub.rs:49:5
    |
 LL | /     if u_16 > 0 {
 LL | |         u_16 -= 1;
@@ -25,7 +25,7 @@ LL | |     }
    | |_____^ help: try: `u_16 = u_16.saturating_sub(1);`
 
 error: implicitly performing saturating subtraction
-  --> $DIR/implicit_saturating_sub.rs:44:5
+  --> $DIR/implicit_saturating_sub.rs:59:5
    |
 LL | /     if u_32 != 0 {
 LL | |         u_32 -= 1;
@@ -33,7 +33,7 @@ LL | |     }
    | |_____^ help: try: `u_32 = u_32.saturating_sub(1);`
 
 error: implicitly performing saturating subtraction
-  --> $DIR/implicit_saturating_sub.rs:65:5
+  --> $DIR/implicit_saturating_sub.rs:80:5
    |
 LL | /     if u_64 > 0 {
 LL | |         u_64 -= 1;
@@ -41,7 +41,7 @@ LL | |     }
    | |_____^ help: try: `u_64 = u_64.saturating_sub(1);`
 
 error: implicitly performing saturating subtraction
-  --> $DIR/implicit_saturating_sub.rs:70:5
+  --> $DIR/implicit_saturating_sub.rs:85:5
    |
 LL | /     if 0 < u_64 {
 LL | |         u_64 -= 1;
@@ -49,7 +49,7 @@ LL | |     }
    | |_____^ help: try: `u_64 = u_64.saturating_sub(1);`
 
 error: implicitly performing saturating subtraction
-  --> $DIR/implicit_saturating_sub.rs:75:5
+  --> $DIR/implicit_saturating_sub.rs:90:5
    |
 LL | /     if 0 != u_64 {
 LL | |         u_64 -= 1;
@@ -57,41 +57,25 @@ LL | |     }
    | |_____^ help: try: `u_64 = u_64.saturating_sub(1);`
 
 error: implicitly performing saturating subtraction
-  --> $DIR/implicit_saturating_sub.rs:96:5
+  --> $DIR/implicit_saturating_sub.rs:111:5
    |
 LL | /     if u_usize > 0 {
 LL | |         u_usize -= 1;
 LL | |     }
    | |_____^ help: try: `u_usize = u_usize.saturating_sub(1);`
 
-error: implicitly performing saturating subtraction
-  --> $DIR/implicit_saturating_sub.rs:108:5
-   |
-LL | /     if i_8 > i8::MIN {
-LL | |         i_8 -= 1;
-LL | |     }
-   | |_____^ help: try: `i_8 = i_8.saturating_sub(1);`
-
-error: implicitly performing saturating subtraction
-  --> $DIR/implicit_saturating_sub.rs:113:5
-   |
-LL | /     if i_8 > i8::MIN {
-LL | |         i_8 -= 1;
-LL | |     }
-   | |_____^ help: try: `i_8 = i_8.saturating_sub(1);`
-
-error: implicitly performing saturating subtraction
-  --> $DIR/implicit_saturating_sub.rs:118:5
-   |
-LL | /     if i_8 != i8::MIN {
-LL | |         i_8 -= 1;
-LL | |     }
-   | |_____^ help: try: `i_8 = i_8.saturating_sub(1);`
-
 error: implicitly performing saturating subtraction
   --> $DIR/implicit_saturating_sub.rs:123:5
    |
-LL | /     if i_8 != i8::MIN {
+LL | /     if i_8 > i8::MIN {
+LL | |         i_8 -= 1;
+LL | |     }
+   | |_____^ help: try: `i_8 = i_8.saturating_sub(1);`
+
+error: implicitly performing saturating subtraction
+  --> $DIR/implicit_saturating_sub.rs:128:5
+   |
+LL | /     if i_8 > i8::MIN {
 LL | |         i_8 -= 1;
 LL | |     }
    | |_____^ help: try: `i_8 = i_8.saturating_sub(1);`
@@ -99,31 +83,31 @@ LL | |     }
 error: implicitly performing saturating subtraction
   --> $DIR/implicit_saturating_sub.rs:133:5
    |
-LL | /     if i_16 > i16::MIN {
-LL | |         i_16 -= 1;
+LL | /     if i_8 != i8::MIN {
+LL | |         i_8 -= 1;
 LL | |     }
-   | |_____^ help: try: `i_16 = i_16.saturating_sub(1);`
+   | |_____^ help: try: `i_8 = i_8.saturating_sub(1);`
 
 error: implicitly performing saturating subtraction
   --> $DIR/implicit_saturating_sub.rs:138:5
    |
+LL | /     if i_8 != i8::MIN {
+LL | |         i_8 -= 1;
+LL | |     }
+   | |_____^ help: try: `i_8 = i_8.saturating_sub(1);`
+
+error: implicitly performing saturating subtraction
+  --> $DIR/implicit_saturating_sub.rs:148:5
+   |
 LL | /     if i_16 > i16::MIN {
 LL | |         i_16 -= 1;
 LL | |     }
    | |_____^ help: try: `i_16 = i_16.saturating_sub(1);`
 
 error: implicitly performing saturating subtraction
-  --> $DIR/implicit_saturating_sub.rs:143:5
+  --> $DIR/implicit_saturating_sub.rs:153:5
    |
-LL | /     if i_16 != i16::MIN {
-LL | |         i_16 -= 1;
-LL | |     }
-   | |_____^ help: try: `i_16 = i_16.saturating_sub(1);`
-
-error: implicitly performing saturating subtraction
-  --> $DIR/implicit_saturating_sub.rs:148:5
-   |
-LL | /     if i_16 != i16::MIN {
+LL | /     if i_16 > i16::MIN {
 LL | |         i_16 -= 1;
 LL | |     }
    | |_____^ help: try: `i_16 = i_16.saturating_sub(1);`
@@ -131,31 +115,31 @@ LL | |     }
 error: implicitly performing saturating subtraction
   --> $DIR/implicit_saturating_sub.rs:158:5
    |
-LL | /     if i_32 > i32::MIN {
-LL | |         i_32 -= 1;
+LL | /     if i_16 != i16::MIN {
+LL | |         i_16 -= 1;
 LL | |     }
-   | |_____^ help: try: `i_32 = i_32.saturating_sub(1);`
+   | |_____^ help: try: `i_16 = i_16.saturating_sub(1);`
 
 error: implicitly performing saturating subtraction
   --> $DIR/implicit_saturating_sub.rs:163:5
    |
+LL | /     if i_16 != i16::MIN {
+LL | |         i_16 -= 1;
+LL | |     }
+   | |_____^ help: try: `i_16 = i_16.saturating_sub(1);`
+
+error: implicitly performing saturating subtraction
+  --> $DIR/implicit_saturating_sub.rs:173:5
+   |
 LL | /     if i_32 > i32::MIN {
 LL | |         i_32 -= 1;
 LL | |     }
    | |_____^ help: try: `i_32 = i_32.saturating_sub(1);`
 
 error: implicitly performing saturating subtraction
-  --> $DIR/implicit_saturating_sub.rs:168:5
+  --> $DIR/implicit_saturating_sub.rs:178:5
    |
-LL | /     if i_32 != i32::MIN {
-LL | |         i_32 -= 1;
-LL | |     }
-   | |_____^ help: try: `i_32 = i_32.saturating_sub(1);`
-
-error: implicitly performing saturating subtraction
-  --> $DIR/implicit_saturating_sub.rs:173:5
-   |
-LL | /     if i_32 != i32::MIN {
+LL | /     if i_32 > i32::MIN {
 LL | |         i_32 -= 1;
 LL | |     }
    | |_____^ help: try: `i_32 = i_32.saturating_sub(1);`
@@ -163,13 +147,29 @@ LL | |     }
 error: implicitly performing saturating subtraction
   --> $DIR/implicit_saturating_sub.rs:183:5
    |
+LL | /     if i_32 != i32::MIN {
+LL | |         i_32 -= 1;
+LL | |     }
+   | |_____^ help: try: `i_32 = i_32.saturating_sub(1);`
+
+error: implicitly performing saturating subtraction
+  --> $DIR/implicit_saturating_sub.rs:188:5
+   |
+LL | /     if i_32 != i32::MIN {
+LL | |         i_32 -= 1;
+LL | |     }
+   | |_____^ help: try: `i_32 = i_32.saturating_sub(1);`
+
+error: implicitly performing saturating subtraction
+  --> $DIR/implicit_saturating_sub.rs:198:5
+   |
 LL | /     if i64::MIN < i_64 {
 LL | |         i_64 -= 1;
 LL | |     }
    | |_____^ help: try: `i_64 = i_64.saturating_sub(1);`
 
 error: implicitly performing saturating subtraction
-  --> $DIR/implicit_saturating_sub.rs:188:5
+  --> $DIR/implicit_saturating_sub.rs:203:5
    |
 LL | /     if i64::MIN != i_64 {
 LL | |         i_64 -= 1;
@@ -177,7 +177,7 @@ LL | |     }
    | |_____^ help: try: `i_64 = i_64.saturating_sub(1);`
 
 error: implicitly performing saturating subtraction
-  --> $DIR/implicit_saturating_sub.rs:193:5
+  --> $DIR/implicit_saturating_sub.rs:208:5
    |
 LL | /     if i64::MIN < i_64 {
 LL | |         i_64 -= 1;
diff --git a/src/tools/clippy/tests/ui/literals.rs b/src/tools/clippy/tests/ui/literals.rs
index 0cadd5a3da19..1a646e49ce3a 100644
--- a/src/tools/clippy/tests/ui/literals.rs
+++ b/src/tools/clippy/tests/ui/literals.rs
@@ -40,3 +40,10 @@ fn main() {
     let ok26 = 0x6_A0_BF;
     let ok27 = 0b1_0010_0101;
 }
+
+fn issue9651() {
+    // lint but octal form is not possible here
+    let _ = 08;
+    let _ = 09;
+    let _ = 089;
+}
diff --git a/src/tools/clippy/tests/ui/literals.stderr b/src/tools/clippy/tests/ui/literals.stderr
index 365b24074735..603d47bacca8 100644
--- a/src/tools/clippy/tests/ui/literals.stderr
+++ b/src/tools/clippy/tests/ui/literals.stderr
@@ -135,5 +135,38 @@ error: digits of hex or binary literal not grouped by four
 LL |     let fail25 = 0b01_100_101;
    |                  ^^^^^^^^^^^^ help: consider: `0b0110_0101`
 
-error: aborting due to 18 previous errors
+error: this is a decimal constant
+  --> $DIR/literals.rs:46:13
+   |
+LL |     let _ = 08;
+   |             ^^
+   |
+help: if you mean to use a decimal constant, remove the `0` to avoid confusion
+   |
+LL |     let _ = 8;
+   |             ~
+
+error: this is a decimal constant
+  --> $DIR/literals.rs:47:13
+   |
+LL |     let _ = 09;
+   |             ^^
+   |
+help: if you mean to use a decimal constant, remove the `0` to avoid confusion
+   |
+LL |     let _ = 9;
+   |             ~
+
+error: this is a decimal constant
+  --> $DIR/literals.rs:48:13
+   |
+LL |     let _ = 089;
+   |             ^^^
+   |
+help: if you mean to use a decimal constant, remove the `0` to avoid confusion
+   |
+LL |     let _ = 89;
+   |             ~~
+
+error: aborting due to 21 previous errors
 
diff --git a/src/tools/clippy/tests/ui/manual_assert.edition2018.fixed b/src/tools/clippy/tests/ui/manual_assert.edition2018.fixed
index 26e3b8f63e70..c9a819ba5354 100644
--- a/src/tools/clippy/tests/ui/manual_assert.edition2018.fixed
+++ b/src/tools/clippy/tests/ui/manual_assert.edition2018.fixed
@@ -1,6 +1,6 @@
 // revisions: edition2018 edition2021
-// [edition2018] edition:2018
-// [edition2021] edition:2021
+//[edition2018] edition:2018
+//[edition2021] edition:2021
 // run-rustfix
 
 #![warn(clippy::manual_assert)]
@@ -29,7 +29,9 @@ fn main() {
         panic!("qaqaq{:?}", a);
     }
     assert!(a.is_empty(), "qaqaq{:?}", a);
-    assert!(a.is_empty(), "qwqwq");
+    if !a.is_empty() {
+        panic!("qwqwq");
+    }
     if a.len() == 3 {
         println!("qwq");
         println!("qwq");
@@ -44,21 +46,32 @@ fn main() {
         println!("qwq");
     }
     let b = vec![1, 2, 3];
-    assert!(!b.is_empty(), "panic1");
-    assert!(!(b.is_empty() && a.is_empty()), "panic2");
-    assert!(!(a.is_empty() && !b.is_empty()), "panic3");
-    assert!(!(b.is_empty() || a.is_empty()), "panic4");
-    assert!(!(a.is_empty() || !b.is_empty()), "panic5");
+    if b.is_empty() {
+        panic!("panic1");
+    }
+    if b.is_empty() && a.is_empty() {
+        panic!("panic2");
+    }
+    if a.is_empty() && !b.is_empty() {
+        panic!("panic3");
+    }
+    if b.is_empty() || a.is_empty() {
+        panic!("panic4");
+    }
+    if a.is_empty() || !b.is_empty() {
+        panic!("panic5");
+    }
     assert!(!a.is_empty(), "with expansion {}", one!());
 }
 
 fn issue7730(a: u8) {
     // Suggestion should preserve comment
-    // comment
-/* this is a
+    if a > 2 {
+        // comment
+        /* this is a
         multiline
         comment */
-/// Doc comment
-// comment after `panic!`
-assert!(!(a > 2), "panic with comment");
+        /// Doc comment
+        panic!("panic with comment") // comment after `panic!`
+    }
 }
diff --git a/src/tools/clippy/tests/ui/manual_assert.edition2018.stderr b/src/tools/clippy/tests/ui/manual_assert.edition2018.stderr
index 237638ee1344..1f2e1e3087bd 100644
--- a/src/tools/clippy/tests/ui/manual_assert.edition2018.stderr
+++ b/src/tools/clippy/tests/ui/manual_assert.edition2018.stderr
@@ -8,54 +8,6 @@ LL | |     }
    |
    = note: `-D clippy::manual-assert` implied by `-D warnings`
 
-error: only a `panic!` in `if`-then statement
-  --> $DIR/manual_assert.rs:34:5
-   |
-LL | /     if !a.is_empty() {
-LL | |         panic!("qwqwq");
-LL | |     }
-   | |_____^ help: try instead: `assert!(a.is_empty(), "qwqwq");`
-
-error: only a `panic!` in `if`-then statement
-  --> $DIR/manual_assert.rs:51:5
-   |
-LL | /     if b.is_empty() {
-LL | |         panic!("panic1");
-LL | |     }
-   | |_____^ help: try instead: `assert!(!b.is_empty(), "panic1");`
-
-error: only a `panic!` in `if`-then statement
-  --> $DIR/manual_assert.rs:54:5
-   |
-LL | /     if b.is_empty() && a.is_empty() {
-LL | |         panic!("panic2");
-LL | |     }
-   | |_____^ help: try instead: `assert!(!(b.is_empty() && a.is_empty()), "panic2");`
-
-error: only a `panic!` in `if`-then statement
-  --> $DIR/manual_assert.rs:57:5
-   |
-LL | /     if a.is_empty() && !b.is_empty() {
-LL | |         panic!("panic3");
-LL | |     }
-   | |_____^ help: try instead: `assert!(!(a.is_empty() && !b.is_empty()), "panic3");`
-
-error: only a `panic!` in `if`-then statement
-  --> $DIR/manual_assert.rs:60:5
-   |
-LL | /     if b.is_empty() || a.is_empty() {
-LL | |         panic!("panic4");
-LL | |     }
-   | |_____^ help: try instead: `assert!(!(b.is_empty() || a.is_empty()), "panic4");`
-
-error: only a `panic!` in `if`-then statement
-  --> $DIR/manual_assert.rs:63:5
-   |
-LL | /     if a.is_empty() || !b.is_empty() {
-LL | |         panic!("panic5");
-LL | |     }
-   | |_____^ help: try instead: `assert!(!(a.is_empty() || !b.is_empty()), "panic5");`
-
 error: only a `panic!` in `if`-then statement
   --> $DIR/manual_assert.rs:66:5
    |
@@ -64,22 +16,5 @@ LL | |         panic!("with expansion {}", one!())
 LL | |     }
    | |_____^ help: try instead: `assert!(!a.is_empty(), "with expansion {}", one!());`
 
-error: only a `panic!` in `if`-then statement
-  --> $DIR/manual_assert.rs:73:5
-   |
-LL | /     if a > 2 {
-LL | |         // comment
-LL | |         /* this is a
-LL | |         multiline
-...  |
-LL | |         panic!("panic with comment") // comment after `panic!`
-LL | |     }
-   | |_____^
-   |
-help: try instead
-   |
-LL |     assert!(!(a > 2), "panic with comment");
-   |
-
-error: aborting due to 9 previous errors
+error: aborting due to 2 previous errors
 
diff --git a/src/tools/clippy/tests/ui/manual_assert.edition2021.fixed b/src/tools/clippy/tests/ui/manual_assert.edition2021.fixed
index 26e3b8f63e70..2f62de51cadc 100644
--- a/src/tools/clippy/tests/ui/manual_assert.edition2021.fixed
+++ b/src/tools/clippy/tests/ui/manual_assert.edition2021.fixed
@@ -1,6 +1,6 @@
 // revisions: edition2018 edition2021
-// [edition2018] edition:2018
-// [edition2021] edition:2021
+//[edition2018] edition:2018
+//[edition2021] edition:2021
 // run-rustfix
 
 #![warn(clippy::manual_assert)]
diff --git a/src/tools/clippy/tests/ui/manual_assert.rs b/src/tools/clippy/tests/ui/manual_assert.rs
index 8c37753071df..6a4cc2468d41 100644
--- a/src/tools/clippy/tests/ui/manual_assert.rs
+++ b/src/tools/clippy/tests/ui/manual_assert.rs
@@ -1,6 +1,6 @@
 // revisions: edition2018 edition2021
-// [edition2018] edition:2018
-// [edition2021] edition:2021
+//[edition2018] edition:2018
+//[edition2021] edition:2021
 // run-rustfix
 
 #![warn(clippy::manual_assert)]
diff --git a/src/tools/clippy/tests/ui/manual_clamp.rs b/src/tools/clippy/tests/ui/manual_clamp.rs
index 54fd888af99f..331fd29b74e8 100644
--- a/src/tools/clippy/tests/ui/manual_clamp.rs
+++ b/src/tools/clippy/tests/ui/manual_clamp.rs
@@ -1,3 +1,4 @@
+#![feature(custom_inner_attributes)]
 #![warn(clippy::manual_clamp)]
 #![allow(
     unused,
@@ -302,3 +303,29 @@ fn dont_tell_me_what_to_do() {
 fn cmp_min_max(input: i32) -> i32 {
     input * 3
 }
+
+fn msrv_1_49() {
+    #![clippy::msrv = "1.49"]
+
+    let (input, min, max) = (0, -1, 2);
+    let _ = if input < min {
+        min
+    } else if input > max {
+        max
+    } else {
+        input
+    };
+}
+
+fn msrv_1_50() {
+    #![clippy::msrv = "1.50"]
+
+    let (input, min, max) = (0, -1, 2);
+    let _ = if input < min {
+        min
+    } else if input > max {
+        max
+    } else {
+        input
+    };
+}
diff --git a/src/tools/clippy/tests/ui/manual_clamp.stderr b/src/tools/clippy/tests/ui/manual_clamp.stderr
index 0604f8606c3f..70abe28091c9 100644
--- a/src/tools/clippy/tests/ui/manual_clamp.stderr
+++ b/src/tools/clippy/tests/ui/manual_clamp.stderr
@@ -1,5 +1,5 @@
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:76:5
+  --> $DIR/manual_clamp.rs:77:5
    |
 LL | /     if x9 < min {
 LL | |         x9 = min;
@@ -13,7 +13,7 @@ LL | |     }
    = note: `-D clippy::manual-clamp` implied by `-D warnings`
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:91:5
+  --> $DIR/manual_clamp.rs:92:5
    |
 LL | /     if x11 > max {
 LL | |         x11 = max;
@@ -26,7 +26,7 @@ LL | |     }
    = note: clamp will panic if max < min
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:99:5
+  --> $DIR/manual_clamp.rs:100:5
    |
 LL | /     if min > x12 {
 LL | |         x12 = min;
@@ -39,7 +39,7 @@ LL | |     }
    = note: clamp will panic if max < min
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:107:5
+  --> $DIR/manual_clamp.rs:108:5
    |
 LL | /     if max < x13 {
 LL | |         x13 = max;
@@ -52,7 +52,7 @@ LL | |     }
    = note: clamp will panic if max < min
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:161:5
+  --> $DIR/manual_clamp.rs:162:5
    |
 LL | /     if max < x33 {
 LL | |         x33 = max;
@@ -65,7 +65,7 @@ LL | |     }
    = note: clamp will panic if max < min
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:21:14
+  --> $DIR/manual_clamp.rs:22:14
    |
 LL |       let x0 = if max < input {
    |  ______________^
@@ -80,7 +80,7 @@ LL | |     };
    = note: clamp will panic if max < min
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:29:14
+  --> $DIR/manual_clamp.rs:30:14
    |
 LL |       let x1 = if input > max {
    |  ______________^
@@ -95,7 +95,7 @@ LL | |     };
    = note: clamp will panic if max < min
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:37:14
+  --> $DIR/manual_clamp.rs:38:14
    |
 LL |       let x2 = if input < min {
    |  ______________^
@@ -110,7 +110,7 @@ LL | |     };
    = note: clamp will panic if max < min
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:45:14
+  --> $DIR/manual_clamp.rs:46:14
    |
 LL |       let x3 = if min > input {
    |  ______________^
@@ -125,7 +125,7 @@ LL | |     };
    = note: clamp will panic if max < min
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:53:14
+  --> $DIR/manual_clamp.rs:54:14
    |
 LL |     let x4 = input.max(min).min(max);
    |              ^^^^^^^^^^^^^^^^^^^^^^^ help: replace with clamp: `input.clamp(min, max)`
@@ -133,7 +133,7 @@ LL |     let x4 = input.max(min).min(max);
    = note: clamp will panic if max < min
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:55:14
+  --> $DIR/manual_clamp.rs:56:14
    |
 LL |     let x5 = input.min(max).max(min);
    |              ^^^^^^^^^^^^^^^^^^^^^^^ help: replace with clamp: `input.clamp(min, max)`
@@ -141,7 +141,7 @@ LL |     let x5 = input.min(max).max(min);
    = note: clamp will panic if max < min
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:57:14
+  --> $DIR/manual_clamp.rs:58:14
    |
 LL |       let x6 = match input {
    |  ______________^
@@ -154,7 +154,7 @@ LL | |     };
    = note: clamp will panic if max < min
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:63:14
+  --> $DIR/manual_clamp.rs:64:14
    |
 LL |       let x7 = match input {
    |  ______________^
@@ -167,7 +167,7 @@ LL | |     };
    = note: clamp will panic if max < min
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:69:14
+  --> $DIR/manual_clamp.rs:70:14
    |
 LL |       let x8 = match input {
    |  ______________^
@@ -180,7 +180,7 @@ LL | |     };
    = note: clamp will panic if max < min
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:83:15
+  --> $DIR/manual_clamp.rs:84:15
    |
 LL |       let x10 = match input {
    |  _______________^
@@ -193,7 +193,7 @@ LL | |     };
    = note: clamp will panic if max < min
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:114:15
+  --> $DIR/manual_clamp.rs:115:15
    |
 LL |       let x14 = if input > CONST_MAX {
    |  _______________^
@@ -208,7 +208,7 @@ LL | |     };
    = note: clamp will panic if max < min
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:123:19
+  --> $DIR/manual_clamp.rs:124:19
    |
 LL |           let x15 = if input > max {
    |  ___________________^
@@ -224,7 +224,7 @@ LL | |         };
    = note: clamp returns NaN if the input is NaN
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:134:19
+  --> $DIR/manual_clamp.rs:135:19
    |
 LL |         let x16 = cmp_max(cmp_min(input, CONST_MAX), CONST_MIN);
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace with clamp: `input.clamp(CONST_MIN, CONST_MAX)`
@@ -232,7 +232,7 @@ LL |         let x16 = cmp_max(cmp_min(input, CONST_MAX), CONST_MIN);
    = note: clamp will panic if max < min
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:135:19
+  --> $DIR/manual_clamp.rs:136:19
    |
 LL |         let x17 = cmp_min(cmp_max(input, CONST_MIN), CONST_MAX);
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace with clamp: `input.clamp(CONST_MIN, CONST_MAX)`
@@ -240,7 +240,7 @@ LL |         let x17 = cmp_min(cmp_max(input, CONST_MIN), CONST_MAX);
    = note: clamp will panic if max < min
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:136:19
+  --> $DIR/manual_clamp.rs:137:19
    |
 LL |         let x18 = cmp_max(CONST_MIN, cmp_min(input, CONST_MAX));
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace with clamp: `input.clamp(CONST_MIN, CONST_MAX)`
@@ -248,7 +248,7 @@ LL |         let x18 = cmp_max(CONST_MIN, cmp_min(input, CONST_MAX));
    = note: clamp will panic if max < min
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:137:19
+  --> $DIR/manual_clamp.rs:138:19
    |
 LL |         let x19 = cmp_min(CONST_MAX, cmp_max(input, CONST_MIN));
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace with clamp: `input.clamp(CONST_MIN, CONST_MAX)`
@@ -256,7 +256,7 @@ LL |         let x19 = cmp_min(CONST_MAX, cmp_max(input, CONST_MIN));
    = note: clamp will panic if max < min
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:138:19
+  --> $DIR/manual_clamp.rs:139:19
    |
 LL |         let x20 = cmp_max(cmp_min(CONST_MAX, input), CONST_MIN);
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace with clamp: `input.clamp(CONST_MIN, CONST_MAX)`
@@ -264,7 +264,7 @@ LL |         let x20 = cmp_max(cmp_min(CONST_MAX, input), CONST_MIN);
    = note: clamp will panic if max < min
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:139:19
+  --> $DIR/manual_clamp.rs:140:19
    |
 LL |         let x21 = cmp_min(cmp_max(CONST_MIN, input), CONST_MAX);
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace with clamp: `input.clamp(CONST_MIN, CONST_MAX)`
@@ -272,7 +272,7 @@ LL |         let x21 = cmp_min(cmp_max(CONST_MIN, input), CONST_MAX);
    = note: clamp will panic if max < min
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:140:19
+  --> $DIR/manual_clamp.rs:141:19
    |
 LL |         let x22 = cmp_max(CONST_MIN, cmp_min(CONST_MAX, input));
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace with clamp: `input.clamp(CONST_MIN, CONST_MAX)`
@@ -280,7 +280,7 @@ LL |         let x22 = cmp_max(CONST_MIN, cmp_min(CONST_MAX, input));
    = note: clamp will panic if max < min
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:141:19
+  --> $DIR/manual_clamp.rs:142:19
    |
 LL |         let x23 = cmp_min(CONST_MAX, cmp_max(CONST_MIN, input));
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace with clamp: `input.clamp(CONST_MIN, CONST_MAX)`
@@ -288,7 +288,7 @@ LL |         let x23 = cmp_min(CONST_MAX, cmp_max(CONST_MIN, input));
    = note: clamp will panic if max < min
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:143:19
+  --> $DIR/manual_clamp.rs:144:19
    |
 LL |         let x24 = f64::max(f64::min(input, CONST_F64_MAX), CONST_F64_MIN);
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace with clamp: `input.clamp(CONST_F64_MIN, CONST_F64_MAX)`
@@ -297,7 +297,7 @@ LL |         let x24 = f64::max(f64::min(input, CONST_F64_MAX), CONST_F64_MIN);
    = note: clamp returns NaN if the input is NaN
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:144:19
+  --> $DIR/manual_clamp.rs:145:19
    |
 LL |         let x25 = f64::min(f64::max(input, CONST_F64_MIN), CONST_F64_MAX);
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace with clamp: `input.clamp(CONST_F64_MIN, CONST_F64_MAX)`
@@ -306,7 +306,7 @@ LL |         let x25 = f64::min(f64::max(input, CONST_F64_MIN), CONST_F64_MAX);
    = note: clamp returns NaN if the input is NaN
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:145:19
+  --> $DIR/manual_clamp.rs:146:19
    |
 LL |         let x26 = f64::max(CONST_F64_MIN, f64::min(input, CONST_F64_MAX));
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace with clamp: `input.clamp(CONST_F64_MIN, CONST_F64_MAX)`
@@ -315,7 +315,7 @@ LL |         let x26 = f64::max(CONST_F64_MIN, f64::min(input, CONST_F64_MAX));
    = note: clamp returns NaN if the input is NaN
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:146:19
+  --> $DIR/manual_clamp.rs:147:19
    |
 LL |         let x27 = f64::min(CONST_F64_MAX, f64::max(input, CONST_F64_MIN));
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace with clamp: `input.clamp(CONST_F64_MIN, CONST_F64_MAX)`
@@ -324,7 +324,7 @@ LL |         let x27 = f64::min(CONST_F64_MAX, f64::max(input, CONST_F64_MIN));
    = note: clamp returns NaN if the input is NaN
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:147:19
+  --> $DIR/manual_clamp.rs:148:19
    |
 LL |         let x28 = f64::max(f64::min(CONST_F64_MAX, input), CONST_F64_MIN);
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace with clamp: `input.clamp(CONST_F64_MIN, CONST_F64_MAX)`
@@ -333,7 +333,7 @@ LL |         let x28 = f64::max(f64::min(CONST_F64_MAX, input), CONST_F64_MIN);
    = note: clamp returns NaN if the input is NaN
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:148:19
+  --> $DIR/manual_clamp.rs:149:19
    |
 LL |         let x29 = f64::min(f64::max(CONST_F64_MIN, input), CONST_F64_MAX);
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace with clamp: `input.clamp(CONST_F64_MIN, CONST_F64_MAX)`
@@ -342,7 +342,7 @@ LL |         let x29 = f64::min(f64::max(CONST_F64_MIN, input), CONST_F64_MAX);
    = note: clamp returns NaN if the input is NaN
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:149:19
+  --> $DIR/manual_clamp.rs:150:19
    |
 LL |         let x30 = f64::max(CONST_F64_MIN, f64::min(CONST_F64_MAX, input));
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace with clamp: `input.clamp(CONST_F64_MIN, CONST_F64_MAX)`
@@ -351,7 +351,7 @@ LL |         let x30 = f64::max(CONST_F64_MIN, f64::min(CONST_F64_MAX, input));
    = note: clamp returns NaN if the input is NaN
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:150:19
+  --> $DIR/manual_clamp.rs:151:19
    |
 LL |         let x31 = f64::min(CONST_F64_MAX, f64::max(CONST_F64_MIN, input));
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace with clamp: `input.clamp(CONST_F64_MIN, CONST_F64_MAX)`
@@ -360,7 +360,7 @@ LL |         let x31 = f64::min(CONST_F64_MAX, f64::max(CONST_F64_MIN, input));
    = note: clamp returns NaN if the input is NaN
 
 error: clamp-like pattern without using clamp function
-  --> $DIR/manual_clamp.rs:153:5
+  --> $DIR/manual_clamp.rs:154:5
    |
 LL | /     if x32 < min {
 LL | |         x32 = min;
@@ -371,5 +371,20 @@ LL | |     }
    |
    = note: clamp will panic if max < min
 
-error: aborting due to 34 previous errors
+error: clamp-like pattern without using clamp function
+  --> $DIR/manual_clamp.rs:324:13
+   |
+LL |       let _ = if input < min {
+   |  _____________^
+LL | |         min
+LL | |     } else if input > max {
+LL | |         max
+LL | |     } else {
+LL | |         input
+LL | |     };
+   | |_____^ help: replace with clamp: `input.clamp(min, max)`
+   |
+   = note: clamp will panic if max < min
+
+error: aborting due to 35 previous errors
 
diff --git a/src/tools/clippy/tests/ui/manual_filter.fixed b/src/tools/clippy/tests/ui/manual_filter.fixed
new file mode 100644
index 000000000000..3553291b87df
--- /dev/null
+++ b/src/tools/clippy/tests/ui/manual_filter.fixed
@@ -0,0 +1,119 @@
+// run-rustfix
+
+#![warn(clippy::manual_filter)]
+#![allow(unused_variables, dead_code)]
+
+fn main() {
+    Some(0).filter(|&x| x <= 0);
+
+    Some(1).filter(|&x| x <= 0);
+
+    Some(2).filter(|&x| x <= 0);
+
+    Some(3).filter(|&x| x > 0);
+
+    let y = Some(4);
+    y.filter(|&x| x <= 0);
+
+    Some(5).filter(|&x| x > 0);
+
+    Some(6).as_ref().filter(|&x| x > &0);
+
+    let external_cond = true;
+    Some(String::new()).filter(|x| external_cond);
+
+    Some(7).filter(|&x| external_cond);
+
+    Some(8).filter(|&x| x != 0);
+
+    Some(9).filter(|&x| x > 10 && x < 100);
+
+    const fn f1() {
+        // Don't lint, `.filter` is not const
+        match Some(10) {
+            Some(x) => {
+                if x > 10 && x < 100 {
+                    Some(x)
+                } else {
+                    None
+                }
+            },
+            None => None,
+        };
+    }
+
+    #[allow(clippy::blocks_in_if_conditions)]
+    Some(11).filter(|&x| {
+                println!("foo");
+                x > 10 && x < 100
+            });
+
+    match Some(12) {
+        // Don't Lint, statement is lost by `.filter`
+        Some(x) => {
+            if x > 10 && x < 100 {
+                println!("foo");
+                Some(x)
+            } else {
+                None
+            }
+        },
+        None => None,
+    };
+
+    match Some(13) {
+        // Don't Lint, because of `None => Some(1)`
+        Some(x) => {
+            if x > 10 && x < 100 {
+                println!("foo");
+                Some(x)
+            } else {
+                None
+            }
+        },
+        None => Some(1),
+    };
+
+    unsafe fn f(x: u32) -> bool {
+        true
+    }
+    let _ = Some(14).filter(|&x| unsafe { f(x) });
+    let _ = Some(15).filter(|&x| unsafe { f(x) });
+
+    #[allow(clippy::redundant_pattern_matching)]
+    if let Some(_) = Some(16) {
+        Some(16)
+    } else { Some(16).filter(|&x| x % 2 == 0) };
+
+    match Some((17, 17)) {
+        // Not linted for now could be
+        Some((x, y)) => {
+            if y != x {
+                Some((x, y))
+            } else {
+                None
+            }
+        },
+        None => None,
+    };
+
+    struct NamedTuple {
+        pub x: u8,
+        pub y: (i32, u32),
+    }
+
+    match Some(NamedTuple {
+        // Not linted for now could be
+        x: 17,
+        y: (18, 19),
+    }) {
+        Some(NamedTuple { x, y }) => {
+            if y.1 != x as u32 {
+                Some(NamedTuple { x, y })
+            } else {
+                None
+            }
+        },
+        None => None,
+    };
+}
diff --git a/src/tools/clippy/tests/ui/manual_filter.rs b/src/tools/clippy/tests/ui/manual_filter.rs
new file mode 100644
index 000000000000..aa9f90f752b1
--- /dev/null
+++ b/src/tools/clippy/tests/ui/manual_filter.rs
@@ -0,0 +1,243 @@
+// run-rustfix
+
+#![warn(clippy::manual_filter)]
+#![allow(unused_variables, dead_code)]
+
+fn main() {
+    match Some(0) {
+        None => None,
+        Some(x) => {
+            if x > 0 {
+                None
+            } else {
+                Some(x)
+            }
+        },
+    };
+
+    match Some(1) {
+        Some(x) => {
+            if x > 0 {
+                None
+            } else {
+                Some(x)
+            }
+        },
+        None => None,
+    };
+
+    match Some(2) {
+        Some(x) => {
+            if x > 0 {
+                None
+            } else {
+                Some(x)
+            }
+        },
+        _ => None,
+    };
+
+    match Some(3) {
+        Some(x) => {
+            if x > 0 {
+                Some(x)
+            } else {
+                None
+            }
+        },
+        None => None,
+    };
+
+    let y = Some(4);
+    match y {
+        // Some(4)
+        None => None,
+        Some(x) => {
+            if x > 0 {
+                None
+            } else {
+                Some(x)
+            }
+        },
+    };
+
+    match Some(5) {
+        Some(x) => {
+            if x > 0 {
+                Some(x)
+            } else {
+                None
+            }
+        },
+        _ => None,
+    };
+
+    match Some(6) {
+        Some(ref x) => {
+            if x > &0 {
+                Some(x)
+            } else {
+                None
+            }
+        },
+        _ => None,
+    };
+
+    let external_cond = true;
+    match Some(String::new()) {
+        Some(x) => {
+            if external_cond {
+                Some(x)
+            } else {
+                None
+            }
+        },
+        _ => None,
+    };
+
+    if let Some(x) = Some(7) {
+        if external_cond { Some(x) } else { None }
+    } else {
+        None
+    };
+
+    match &Some(8) {
+        &Some(x) => {
+            if x != 0 {
+                Some(x)
+            } else {
+                None
+            }
+        },
+        _ => None,
+    };
+
+    match Some(9) {
+        Some(x) => {
+            if x > 10 && x < 100 {
+                Some(x)
+            } else {
+                None
+            }
+        },
+        None => None,
+    };
+
+    const fn f1() {
+        // Don't lint, `.filter` is not const
+        match Some(10) {
+            Some(x) => {
+                if x > 10 && x < 100 {
+                    Some(x)
+                } else {
+                    None
+                }
+            },
+            None => None,
+        };
+    }
+
+    #[allow(clippy::blocks_in_if_conditions)]
+    match Some(11) {
+        // Lint, statement is preserved by `.filter`
+        Some(x) => {
+            if {
+                println!("foo");
+                x > 10 && x < 100
+            } {
+                Some(x)
+            } else {
+                None
+            }
+        },
+        None => None,
+    };
+
+    match Some(12) {
+        // Don't Lint, statement is lost by `.filter`
+        Some(x) => {
+            if x > 10 && x < 100 {
+                println!("foo");
+                Some(x)
+            } else {
+                None
+            }
+        },
+        None => None,
+    };
+
+    match Some(13) {
+        // Don't Lint, because of `None => Some(1)`
+        Some(x) => {
+            if x > 10 && x < 100 {
+                println!("foo");
+                Some(x)
+            } else {
+                None
+            }
+        },
+        None => Some(1),
+    };
+
+    unsafe fn f(x: u32) -> bool {
+        true
+    }
+    let _ = match Some(14) {
+        Some(x) => {
+            if unsafe { f(x) } {
+                Some(x)
+            } else {
+                None
+            }
+        },
+        None => None,
+    };
+    let _ = match Some(15) {
+        Some(x) => unsafe {
+            if f(x) { Some(x) } else { None }
+        },
+        None => None,
+    };
+
+    #[allow(clippy::redundant_pattern_matching)]
+    if let Some(_) = Some(16) {
+        Some(16)
+    } else if let Some(x) = Some(16) {
+        // Lint starting from here
+        if x % 2 == 0 { Some(x) } else { None }
+    } else {
+        None
+    };
+
+    match Some((17, 17)) {
+        // Not linted for now could be
+        Some((x, y)) => {
+            if y != x {
+                Some((x, y))
+            } else {
+                None
+            }
+        },
+        None => None,
+    };
+
+    struct NamedTuple {
+        pub x: u8,
+        pub y: (i32, u32),
+    }
+
+    match Some(NamedTuple {
+        // Not linted for now could be
+        x: 17,
+        y: (18, 19),
+    }) {
+        Some(NamedTuple { x, y }) => {
+            if y.1 != x as u32 {
+                Some(NamedTuple { x, y })
+            } else {
+                None
+            }
+        },
+        None => None,
+    };
+}
diff --git a/src/tools/clippy/tests/ui/manual_filter.stderr b/src/tools/clippy/tests/ui/manual_filter.stderr
new file mode 100644
index 000000000000..53dea9229306
--- /dev/null
+++ b/src/tools/clippy/tests/ui/manual_filter.stderr
@@ -0,0 +1,191 @@
+error: manual implementation of `Option::filter`
+  --> $DIR/manual_filter.rs:7:5
+   |
+LL | /     match Some(0) {
+LL | |         None => None,
+LL | |         Some(x) => {
+LL | |             if x > 0 {
+...  |
+LL | |         },
+LL | |     };
+   | |_____^ help: try this: `Some(0).filter(|&x| x <= 0)`
+   |
+   = note: `-D clippy::manual-filter` implied by `-D warnings`
+
+error: manual implementation of `Option::filter`
+  --> $DIR/manual_filter.rs:18:5
+   |
+LL | /     match Some(1) {
+LL | |         Some(x) => {
+LL | |             if x > 0 {
+LL | |                 None
+...  |
+LL | |         None => None,
+LL | |     };
+   | |_____^ help: try this: `Some(1).filter(|&x| x <= 0)`
+
+error: manual implementation of `Option::filter`
+  --> $DIR/manual_filter.rs:29:5
+   |
+LL | /     match Some(2) {
+LL | |         Some(x) => {
+LL | |             if x > 0 {
+LL | |                 None
+...  |
+LL | |         _ => None,
+LL | |     };
+   | |_____^ help: try this: `Some(2).filter(|&x| x <= 0)`
+
+error: manual implementation of `Option::filter`
+  --> $DIR/manual_filter.rs:40:5
+   |
+LL | /     match Some(3) {
+LL | |         Some(x) => {
+LL | |             if x > 0 {
+LL | |                 Some(x)
+...  |
+LL | |         None => None,
+LL | |     };
+   | |_____^ help: try this: `Some(3).filter(|&x| x > 0)`
+
+error: manual implementation of `Option::filter`
+  --> $DIR/manual_filter.rs:52:5
+   |
+LL | /     match y {
+LL | |         // Some(4)
+LL | |         None => None,
+LL | |         Some(x) => {
+...  |
+LL | |         },
+LL | |     };
+   | |_____^ help: try this: `y.filter(|&x| x <= 0)`
+
+error: manual implementation of `Option::filter`
+  --> $DIR/manual_filter.rs:64:5
+   |
+LL | /     match Some(5) {
+LL | |         Some(x) => {
+LL | |             if x > 0 {
+LL | |                 Some(x)
+...  |
+LL | |         _ => None,
+LL | |     };
+   | |_____^ help: try this: `Some(5).filter(|&x| x > 0)`
+
+error: manual implementation of `Option::filter`
+  --> $DIR/manual_filter.rs:75:5
+   |
+LL | /     match Some(6) {
+LL | |         Some(ref x) => {
+LL | |             if x > &0 {
+LL | |                 Some(x)
+...  |
+LL | |         _ => None,
+LL | |     };
+   | |_____^ help: try this: `Some(6).as_ref().filter(|&x| x > &0)`
+
+error: manual implementation of `Option::filter`
+  --> $DIR/manual_filter.rs:87:5
+   |
+LL | /     match Some(String::new()) {
+LL | |         Some(x) => {
+LL | |             if external_cond {
+LL | |                 Some(x)
+...  |
+LL | |         _ => None,
+LL | |     };
+   | |_____^ help: try this: `Some(String::new()).filter(|x| external_cond)`
+
+error: manual implementation of `Option::filter`
+  --> $DIR/manual_filter.rs:98:5
+   |
+LL | /     if let Some(x) = Some(7) {
+LL | |         if external_cond { Some(x) } else { None }
+LL | |     } else {
+LL | |         None
+LL | |     };
+   | |_____^ help: try this: `Some(7).filter(|&x| external_cond)`
+
+error: manual implementation of `Option::filter`
+  --> $DIR/manual_filter.rs:104:5
+   |
+LL | /     match &Some(8) {
+LL | |         &Some(x) => {
+LL | |             if x != 0 {
+LL | |                 Some(x)
+...  |
+LL | |         _ => None,
+LL | |     };
+   | |_____^ help: try this: `Some(8).filter(|&x| x != 0)`
+
+error: manual implementation of `Option::filter`
+  --> $DIR/manual_filter.rs:115:5
+   |
+LL | /     match Some(9) {
+LL | |         Some(x) => {
+LL | |             if x > 10 && x < 100 {
+LL | |                 Some(x)
+...  |
+LL | |         None => None,
+LL | |     };
+   | |_____^ help: try this: `Some(9).filter(|&x| x > 10 && x < 100)`
+
+error: manual implementation of `Option::filter`
+  --> $DIR/manual_filter.rs:141:5
+   |
+LL | /     match Some(11) {
+LL | |         // Lint, statement is preserved by `.filter`
+LL | |         Some(x) => {
+LL | |             if {
+...  |
+LL | |         None => None,
+LL | |     };
+   | |_____^
+   |
+help: try this
+   |
+LL ~     Some(11).filter(|&x| {
+LL +                 println!("foo");
+LL +                 x > 10 && x < 100
+LL ~             });
+   |
+
+error: manual implementation of `Option::filter`
+  --> $DIR/manual_filter.rs:185:13
+   |
+LL |       let _ = match Some(14) {
+   |  _____________^
+LL | |         Some(x) => {
+LL | |             if unsafe { f(x) } {
+LL | |                 Some(x)
+...  |
+LL | |         None => None,
+LL | |     };
+   | |_____^ help: try this: `Some(14).filter(|&x| unsafe { f(x) })`
+
+error: manual implementation of `Option::filter`
+  --> $DIR/manual_filter.rs:195:13
+   |
+LL |       let _ = match Some(15) {
+   |  _____________^
+LL | |         Some(x) => unsafe {
+LL | |             if f(x) { Some(x) } else { None }
+LL | |         },
+LL | |         None => None,
+LL | |     };
+   | |_____^ help: try this: `Some(15).filter(|&x| unsafe { f(x) })`
+
+error: manual implementation of `Option::filter`
+  --> $DIR/manual_filter.rs:205:12
+   |
+LL |       } else if let Some(x) = Some(16) {
+   |  ____________^
+LL | |         // Lint starting from here
+LL | |         if x % 2 == 0 { Some(x) } else { None }
+LL | |     } else {
+LL | |         None
+LL | |     };
+   | |_____^ help: try this: `{ Some(16).filter(|&x| x % 2 == 0) }`
+
+error: aborting due to 15 previous errors
+
diff --git a/src/tools/clippy/tests/ui/manual_rem_euclid.fixed b/src/tools/clippy/tests/ui/manual_rem_euclid.fixed
index 5601c96c10b2..b942fbfe9305 100644
--- a/src/tools/clippy/tests/ui/manual_rem_euclid.fixed
+++ b/src/tools/clippy/tests/ui/manual_rem_euclid.fixed
@@ -1,6 +1,7 @@
 // run-rustfix
 // aux-build:macro_rules.rs
 
+#![feature(custom_inner_attributes)]
 #![warn(clippy::manual_rem_euclid)]
 
 #[macro_use]
@@ -53,3 +54,32 @@ pub fn rem_euclid_4(num: i32) -> i32 {
 pub const fn const_rem_euclid_4(num: i32) -> i32 {
     num.rem_euclid(4)
 }
+
+pub fn msrv_1_37() {
+    #![clippy::msrv = "1.37"]
+
+    let x: i32 = 10;
+    let _: i32 = ((x % 4) + 4) % 4;
+}
+
+pub fn msrv_1_38() {
+    #![clippy::msrv = "1.38"]
+
+    let x: i32 = 10;
+    let _: i32 = x.rem_euclid(4);
+}
+
+// For const fns:
+pub const fn msrv_1_51() {
+    #![clippy::msrv = "1.51"]
+
+    let x: i32 = 10;
+    let _: i32 = ((x % 4) + 4) % 4;
+}
+
+pub const fn msrv_1_52() {
+    #![clippy::msrv = "1.52"]
+
+    let x: i32 = 10;
+    let _: i32 = x.rem_euclid(4);
+}
diff --git a/src/tools/clippy/tests/ui/manual_rem_euclid.rs b/src/tools/clippy/tests/ui/manual_rem_euclid.rs
index 52135be26b73..7462d532169f 100644
--- a/src/tools/clippy/tests/ui/manual_rem_euclid.rs
+++ b/src/tools/clippy/tests/ui/manual_rem_euclid.rs
@@ -1,6 +1,7 @@
 // run-rustfix
 // aux-build:macro_rules.rs
 
+#![feature(custom_inner_attributes)]
 #![warn(clippy::manual_rem_euclid)]
 
 #[macro_use]
@@ -53,3 +54,32 @@ pub fn rem_euclid_4(num: i32) -> i32 {
 pub const fn const_rem_euclid_4(num: i32) -> i32 {
     ((num % 4) + 4) % 4
 }
+
+pub fn msrv_1_37() {
+    #![clippy::msrv = "1.37"]
+
+    let x: i32 = 10;
+    let _: i32 = ((x % 4) + 4) % 4;
+}
+
+pub fn msrv_1_38() {
+    #![clippy::msrv = "1.38"]
+
+    let x: i32 = 10;
+    let _: i32 = ((x % 4) + 4) % 4;
+}
+
+// For const fns:
+pub const fn msrv_1_51() {
+    #![clippy::msrv = "1.51"]
+
+    let x: i32 = 10;
+    let _: i32 = ((x % 4) + 4) % 4;
+}
+
+pub const fn msrv_1_52() {
+    #![clippy::msrv = "1.52"]
+
+    let x: i32 = 10;
+    let _: i32 = ((x % 4) + 4) % 4;
+}
diff --git a/src/tools/clippy/tests/ui/manual_rem_euclid.stderr b/src/tools/clippy/tests/ui/manual_rem_euclid.stderr
index a237fd0213c1..d51bac03b565 100644
--- a/src/tools/clippy/tests/ui/manual_rem_euclid.stderr
+++ b/src/tools/clippy/tests/ui/manual_rem_euclid.stderr
@@ -1,5 +1,5 @@
 error: manual `rem_euclid` implementation
-  --> $DIR/manual_rem_euclid.rs:19:18
+  --> $DIR/manual_rem_euclid.rs:20:18
    |
 LL |     let _: i32 = ((value % 4) + 4) % 4;
    |                  ^^^^^^^^^^^^^^^^^^^^^ help: consider using: `value.rem_euclid(4)`
@@ -7,31 +7,31 @@ LL |     let _: i32 = ((value % 4) + 4) % 4;
    = note: `-D clippy::manual-rem-euclid` implied by `-D warnings`
 
 error: manual `rem_euclid` implementation
-  --> $DIR/manual_rem_euclid.rs:20:18
+  --> $DIR/manual_rem_euclid.rs:21:18
    |
 LL |     let _: i32 = (4 + (value % 4)) % 4;
    |                  ^^^^^^^^^^^^^^^^^^^^^ help: consider using: `value.rem_euclid(4)`
 
 error: manual `rem_euclid` implementation
-  --> $DIR/manual_rem_euclid.rs:21:18
+  --> $DIR/manual_rem_euclid.rs:22:18
    |
 LL |     let _: i32 = (value % 4 + 4) % 4;
    |                  ^^^^^^^^^^^^^^^^^^^ help: consider using: `value.rem_euclid(4)`
 
 error: manual `rem_euclid` implementation
-  --> $DIR/manual_rem_euclid.rs:22:18
+  --> $DIR/manual_rem_euclid.rs:23:18
    |
 LL |     let _: i32 = (4 + value % 4) % 4;
    |                  ^^^^^^^^^^^^^^^^^^^ help: consider using: `value.rem_euclid(4)`
 
 error: manual `rem_euclid` implementation
-  --> $DIR/manual_rem_euclid.rs:23:22
+  --> $DIR/manual_rem_euclid.rs:24:22
    |
 LL |     let _: i32 = 1 + (4 + value % 4) % 4;
    |                      ^^^^^^^^^^^^^^^^^^^ help: consider using: `value.rem_euclid(4)`
 
 error: manual `rem_euclid` implementation
-  --> $DIR/manual_rem_euclid.rs:12:22
+  --> $DIR/manual_rem_euclid.rs:13:22
    |
 LL |         let _: i32 = ((value % 4) + 4) % 4;
    |                      ^^^^^^^^^^^^^^^^^^^^^ help: consider using: `value.rem_euclid(4)`
@@ -42,16 +42,28 @@ LL |     internal_rem_euclid!();
    = note: this error originates in the macro `internal_rem_euclid` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: manual `rem_euclid` implementation
-  --> $DIR/manual_rem_euclid.rs:49:5
+  --> $DIR/manual_rem_euclid.rs:50:5
    |
 LL |     ((num % 4) + 4) % 4
    |     ^^^^^^^^^^^^^^^^^^^ help: consider using: `num.rem_euclid(4)`
 
 error: manual `rem_euclid` implementation
-  --> $DIR/manual_rem_euclid.rs:54:5
+  --> $DIR/manual_rem_euclid.rs:55:5
    |
 LL |     ((num % 4) + 4) % 4
    |     ^^^^^^^^^^^^^^^^^^^ help: consider using: `num.rem_euclid(4)`
 
-error: aborting due to 8 previous errors
+error: manual `rem_euclid` implementation
+  --> $DIR/manual_rem_euclid.rs:69:18
+   |
+LL |     let _: i32 = ((x % 4) + 4) % 4;
+   |                  ^^^^^^^^^^^^^^^^^ help: consider using: `x.rem_euclid(4)`
+
+error: manual `rem_euclid` implementation
+  --> $DIR/manual_rem_euclid.rs:84:18
+   |
+LL |     let _: i32 = ((x % 4) + 4) % 4;
+   |                  ^^^^^^^^^^^^^^^^^ help: consider using: `x.rem_euclid(4)`
+
+error: aborting due to 10 previous errors
 
diff --git a/src/tools/clippy/tests/ui/manual_strip.rs b/src/tools/clippy/tests/ui/manual_strip.rs
index cbb84eb5c7e3..85009d78558b 100644
--- a/src/tools/clippy/tests/ui/manual_strip.rs
+++ b/src/tools/clippy/tests/ui/manual_strip.rs
@@ -1,3 +1,4 @@
+#![feature(custom_inner_attributes)]
 #![warn(clippy::manual_strip)]
 
 fn main() {
@@ -64,3 +65,21 @@ fn main() {
         s4[2..].to_string();
     }
 }
+
+fn msrv_1_44() {
+    #![clippy::msrv = "1.44"]
+
+    let s = "abc";
+    if s.starts_with('a') {
+        s[1..].to_string();
+    }
+}
+
+fn msrv_1_45() {
+    #![clippy::msrv = "1.45"]
+
+    let s = "abc";
+    if s.starts_with('a') {
+        s[1..].to_string();
+    }
+}
diff --git a/src/tools/clippy/tests/ui/manual_strip.stderr b/src/tools/clippy/tests/ui/manual_strip.stderr
index 2191ccb85dd5..ad2a362f3e76 100644
--- a/src/tools/clippy/tests/ui/manual_strip.stderr
+++ b/src/tools/clippy/tests/ui/manual_strip.stderr
@@ -1,11 +1,11 @@
 error: stripping a prefix manually
-  --> $DIR/manual_strip.rs:7:24
+  --> $DIR/manual_strip.rs:8:24
    |
 LL |         str::to_string(&s["ab".len()..]);
    |                        ^^^^^^^^^^^^^^^^
    |
 note: the prefix was tested here
-  --> $DIR/manual_strip.rs:6:5
+  --> $DIR/manual_strip.rs:7:5
    |
 LL |     if s.starts_with("ab") {
    |     ^^^^^^^^^^^^^^^^^^^^^^^
@@ -21,13 +21,13 @@ LL ~         <stripped>.to_string();
    |
 
 error: stripping a suffix manually
-  --> $DIR/manual_strip.rs:15:24
+  --> $DIR/manual_strip.rs:16:24
    |
 LL |         str::to_string(&s[..s.len() - "bc".len()]);
    |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
 note: the suffix was tested here
-  --> $DIR/manual_strip.rs:14:5
+  --> $DIR/manual_strip.rs:15:5
    |
 LL |     if s.ends_with("bc") {
    |     ^^^^^^^^^^^^^^^^^^^^^
@@ -42,13 +42,13 @@ LL ~         <stripped>.to_string();
    |
 
 error: stripping a prefix manually
-  --> $DIR/manual_strip.rs:24:24
+  --> $DIR/manual_strip.rs:25:24
    |
 LL |         str::to_string(&s[1..]);
    |                        ^^^^^^^
    |
 note: the prefix was tested here
-  --> $DIR/manual_strip.rs:23:5
+  --> $DIR/manual_strip.rs:24:5
    |
 LL |     if s.starts_with('a') {
    |     ^^^^^^^^^^^^^^^^^^^^^^
@@ -60,13 +60,13 @@ LL ~         <stripped>.to_string();
    |
 
 error: stripping a prefix manually
-  --> $DIR/manual_strip.rs:31:24
+  --> $DIR/manual_strip.rs:32:24
    |
 LL |         str::to_string(&s[prefix.len()..]);
    |                        ^^^^^^^^^^^^^^^^^^
    |
 note: the prefix was tested here
-  --> $DIR/manual_strip.rs:30:5
+  --> $DIR/manual_strip.rs:31:5
    |
 LL |     if s.starts_with(prefix) {
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -77,13 +77,13 @@ LL ~         str::to_string(<stripped>);
    |
 
 error: stripping a prefix manually
-  --> $DIR/manual_strip.rs:37:24
+  --> $DIR/manual_strip.rs:38:24
    |
 LL |         str::to_string(&s[PREFIX.len()..]);
    |                        ^^^^^^^^^^^^^^^^^^
    |
 note: the prefix was tested here
-  --> $DIR/manual_strip.rs:36:5
+  --> $DIR/manual_strip.rs:37:5
    |
 LL |     if s.starts_with(PREFIX) {
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -95,13 +95,13 @@ LL ~         str::to_string(<stripped>);
    |
 
 error: stripping a prefix manually
-  --> $DIR/manual_strip.rs:44:24
+  --> $DIR/manual_strip.rs:45:24
    |
 LL |         str::to_string(&TARGET[prefix.len()..]);
    |                        ^^^^^^^^^^^^^^^^^^^^^^^
    |
 note: the prefix was tested here
-  --> $DIR/manual_strip.rs:43:5
+  --> $DIR/manual_strip.rs:44:5
    |
 LL |     if TARGET.starts_with(prefix) {
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -112,13 +112,13 @@ LL ~         str::to_string(<stripped>);
    |
 
 error: stripping a prefix manually
-  --> $DIR/manual_strip.rs:50:9
+  --> $DIR/manual_strip.rs:51:9
    |
 LL |         s1[2..].to_uppercase();
    |         ^^^^^^^
    |
 note: the prefix was tested here
-  --> $DIR/manual_strip.rs:49:5
+  --> $DIR/manual_strip.rs:50:5
    |
 LL |     if s1.starts_with("ab") {
    |     ^^^^^^^^^^^^^^^^^^^^^^^^
@@ -128,5 +128,22 @@ LL ~     if let Some(<stripped>) = s1.strip_prefix("ab") {
 LL ~         <stripped>.to_uppercase();
    |
 
-error: aborting due to 7 previous errors
+error: stripping a prefix manually
+  --> $DIR/manual_strip.rs:83:9
+   |
+LL |         s[1..].to_string();
+   |         ^^^^^^
+   |
+note: the prefix was tested here
+  --> $DIR/manual_strip.rs:82:5
+   |
+LL |     if s.starts_with('a') {
+   |     ^^^^^^^^^^^^^^^^^^^^^^
+help: try using the `strip_prefix` method
+   |
+LL ~     if let Some(<stripped>) = s.strip_prefix('a') {
+LL ~         <stripped>.to_string();
+   |
+
+error: aborting due to 8 previous errors
 
diff --git a/src/tools/clippy/tests/ui/map_unwrap_or.rs b/src/tools/clippy/tests/ui/map_unwrap_or.rs
index 5429fb4e454e..396b22a9abb3 100644
--- a/src/tools/clippy/tests/ui/map_unwrap_or.rs
+++ b/src/tools/clippy/tests/ui/map_unwrap_or.rs
@@ -1,6 +1,8 @@
 // aux-build:option_helpers.rs
+
+#![feature(custom_inner_attributes)]
 #![warn(clippy::map_unwrap_or)]
-#![allow(clippy::uninlined_format_args)]
+#![allow(clippy::uninlined_format_args, clippy::unnecessary_lazy_evaluations)]
 
 #[macro_use]
 extern crate option_helpers;
@@ -79,3 +81,19 @@ fn main() {
     option_methods();
     result_methods();
 }
+
+fn msrv_1_40() {
+    #![clippy::msrv = "1.40"]
+
+    let res: Result<i32, ()> = Ok(1);
+
+    let _ = res.map(|x| x + 1).unwrap_or_else(|_e| 0);
+}
+
+fn msrv_1_41() {
+    #![clippy::msrv = "1.41"]
+
+    let res: Result<i32, ()> = Ok(1);
+
+    let _ = res.map(|x| x + 1).unwrap_or_else(|_e| 0);
+}
diff --git a/src/tools/clippy/tests/ui/map_unwrap_or.stderr b/src/tools/clippy/tests/ui/map_unwrap_or.stderr
index abc9c1ece327..d17d24a403ea 100644
--- a/src/tools/clippy/tests/ui/map_unwrap_or.stderr
+++ b/src/tools/clippy/tests/ui/map_unwrap_or.stderr
@@ -1,5 +1,5 @@
 error: called `map(<f>).unwrap_or(<a>)` on an `Option` value. This can be done more directly by calling `map_or(<a>, <f>)` instead
-  --> $DIR/map_unwrap_or.rs:16:13
+  --> $DIR/map_unwrap_or.rs:18:13
    |
 LL |       let _ = opt.map(|x| x + 1)
    |  _____________^
@@ -15,7 +15,7 @@ LL +     let _ = opt.map_or(0, |x| x + 1);
    |
 
 error: called `map(<f>).unwrap_or(<a>)` on an `Option` value. This can be done more directly by calling `map_or(<a>, <f>)` instead
-  --> $DIR/map_unwrap_or.rs:20:13
+  --> $DIR/map_unwrap_or.rs:22:13
    |
 LL |       let _ = opt.map(|x| {
    |  _____________^
@@ -33,7 +33,7 @@ LL ~     );
    |
 
 error: called `map(<f>).unwrap_or(<a>)` on an `Option` value. This can be done more directly by calling `map_or(<a>, <f>)` instead
-  --> $DIR/map_unwrap_or.rs:24:13
+  --> $DIR/map_unwrap_or.rs:26:13
    |
 LL |       let _ = opt.map(|x| x + 1)
    |  _____________^
@@ -50,7 +50,7 @@ LL ~         }, |x| x + 1);
    |
 
 error: called `map(<f>).unwrap_or(None)` on an `Option` value. This can be done more directly by calling `and_then(<f>)` instead
-  --> $DIR/map_unwrap_or.rs:29:13
+  --> $DIR/map_unwrap_or.rs:31:13
    |
 LL |     let _ = opt.map(|x| Some(x + 1)).unwrap_or(None);
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -62,7 +62,7 @@ LL +     let _ = opt.and_then(|x| Some(x + 1));
    |
 
 error: called `map(<f>).unwrap_or(None)` on an `Option` value. This can be done more directly by calling `and_then(<f>)` instead
-  --> $DIR/map_unwrap_or.rs:31:13
+  --> $DIR/map_unwrap_or.rs:33:13
    |
 LL |       let _ = opt.map(|x| {
    |  _____________^
@@ -80,7 +80,7 @@ LL ~     );
    |
 
 error: called `map(<f>).unwrap_or(None)` on an `Option` value. This can be done more directly by calling `and_then(<f>)` instead
-  --> $DIR/map_unwrap_or.rs:35:13
+  --> $DIR/map_unwrap_or.rs:37:13
    |
 LL |       let _ = opt
    |  _____________^
@@ -95,7 +95,7 @@ LL +         .and_then(|x| Some(x + 1));
    |
 
 error: called `map(<f>).unwrap_or(<a>)` on an `Option` value. This can be done more directly by calling `map_or(<a>, <f>)` instead
-  --> $DIR/map_unwrap_or.rs:46:13
+  --> $DIR/map_unwrap_or.rs:48:13
    |
 LL |     let _ = Some("prefix").map(|p| format!("{}.", p)).unwrap_or(id);
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -107,7 +107,7 @@ LL +     let _ = Some("prefix").map_or(id, |p| format!("{}.", p));
    |
 
 error: called `map(<f>).unwrap_or_else(<g>)` on an `Option` value. This can be done more directly by calling `map_or_else(<g>, <f>)` instead
-  --> $DIR/map_unwrap_or.rs:50:13
+  --> $DIR/map_unwrap_or.rs:52:13
    |
 LL |       let _ = opt.map(|x| {
    |  _____________^
@@ -117,7 +117,7 @@ LL | |     ).unwrap_or_else(|| 0);
    | |__________________________^
 
 error: called `map(<f>).unwrap_or_else(<g>)` on an `Option` value. This can be done more directly by calling `map_or_else(<g>, <f>)` instead
-  --> $DIR/map_unwrap_or.rs:54:13
+  --> $DIR/map_unwrap_or.rs:56:13
    |
 LL |       let _ = opt.map(|x| x + 1)
    |  _____________^
@@ -127,7 +127,7 @@ LL | |         );
    | |_________^
 
 error: called `map(<f>).unwrap_or_else(<g>)` on a `Result` value. This can be done more directly by calling `.map_or_else(<g>, <f>)` instead
-  --> $DIR/map_unwrap_or.rs:66:13
+  --> $DIR/map_unwrap_or.rs:68:13
    |
 LL |       let _ = res.map(|x| {
    |  _____________^
@@ -137,7 +137,7 @@ LL | |     ).unwrap_or_else(|_e| 0);
    | |____________________________^
 
 error: called `map(<f>).unwrap_or_else(<g>)` on a `Result` value. This can be done more directly by calling `.map_or_else(<g>, <f>)` instead
-  --> $DIR/map_unwrap_or.rs:70:13
+  --> $DIR/map_unwrap_or.rs:72:13
    |
 LL |       let _ = res.map(|x| x + 1)
    |  _____________^
@@ -146,5 +146,11 @@ LL | |             0
 LL | |         });
    | |__________^
 
-error: aborting due to 11 previous errors
+error: called `map(<f>).unwrap_or_else(<g>)` on a `Result` value. This can be done more directly by calling `.map_or_else(<g>, <f>)` instead
+  --> $DIR/map_unwrap_or.rs:98:13
+   |
+LL |     let _ = res.map(|x| x + 1).unwrap_or_else(|_e| 0);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `res.map_or_else(|_e| 0, |x| x + 1)`
+
+error: aborting due to 12 previous errors
 
diff --git a/src/tools/clippy/tests/ui/match_expr_like_matches_macro.fixed b/src/tools/clippy/tests/ui/match_expr_like_matches_macro.fixed
index 95ca571d07bf..2498007694c5 100644
--- a/src/tools/clippy/tests/ui/match_expr_like_matches_macro.fixed
+++ b/src/tools/clippy/tests/ui/match_expr_like_matches_macro.fixed
@@ -1,5 +1,6 @@
 // run-rustfix
 
+#![feature(custom_inner_attributes)]
 #![warn(clippy::match_like_matches_macro)]
 #![allow(unreachable_patterns, dead_code, clippy::equatable_if_let)]
 
@@ -193,3 +194,18 @@ fn main() {
         _ => false,
     };
 }
+
+fn msrv_1_41() {
+    #![clippy::msrv = "1.41"]
+
+    let _y = match Some(5) {
+        Some(0) => true,
+        _ => false,
+    };
+}
+
+fn msrv_1_42() {
+    #![clippy::msrv = "1.42"]
+
+    let _y = matches!(Some(5), Some(0));
+}
diff --git a/src/tools/clippy/tests/ui/match_expr_like_matches_macro.rs b/src/tools/clippy/tests/ui/match_expr_like_matches_macro.rs
index 3b9c8cadadcc..b4e48499bd0f 100644
--- a/src/tools/clippy/tests/ui/match_expr_like_matches_macro.rs
+++ b/src/tools/clippy/tests/ui/match_expr_like_matches_macro.rs
@@ -1,5 +1,6 @@
 // run-rustfix
 
+#![feature(custom_inner_attributes)]
 #![warn(clippy::match_like_matches_macro)]
 #![allow(unreachable_patterns, dead_code, clippy::equatable_if_let)]
 
@@ -234,3 +235,21 @@ fn main() {
         _ => false,
     };
 }
+
+fn msrv_1_41() {
+    #![clippy::msrv = "1.41"]
+
+    let _y = match Some(5) {
+        Some(0) => true,
+        _ => false,
+    };
+}
+
+fn msrv_1_42() {
+    #![clippy::msrv = "1.42"]
+
+    let _y = match Some(5) {
+        Some(0) => true,
+        _ => false,
+    };
+}
diff --git a/src/tools/clippy/tests/ui/match_expr_like_matches_macro.stderr b/src/tools/clippy/tests/ui/match_expr_like_matches_macro.stderr
index e94555e27448..f1d1c23aeb0d 100644
--- a/src/tools/clippy/tests/ui/match_expr_like_matches_macro.stderr
+++ b/src/tools/clippy/tests/ui/match_expr_like_matches_macro.stderr
@@ -1,5 +1,5 @@
 error: match expression looks like `matches!` macro
-  --> $DIR/match_expr_like_matches_macro.rs:10:14
+  --> $DIR/match_expr_like_matches_macro.rs:11:14
    |
 LL |       let _y = match x {
    |  ______________^
@@ -11,7 +11,7 @@ LL | |     };
    = note: `-D clippy::match-like-matches-macro` implied by `-D warnings`
 
 error: match expression looks like `matches!` macro
-  --> $DIR/match_expr_like_matches_macro.rs:16:14
+  --> $DIR/match_expr_like_matches_macro.rs:17:14
    |
 LL |       let _w = match x {
    |  ______________^
@@ -21,7 +21,7 @@ LL | |     };
    | |_____^ help: try this: `matches!(x, Some(_))`
 
 error: redundant pattern matching, consider using `is_none()`
-  --> $DIR/match_expr_like_matches_macro.rs:22:14
+  --> $DIR/match_expr_like_matches_macro.rs:23:14
    |
 LL |       let _z = match x {
    |  ______________^
@@ -33,7 +33,7 @@ LL | |     };
    = note: `-D clippy::redundant-pattern-matching` implied by `-D warnings`
 
 error: match expression looks like `matches!` macro
-  --> $DIR/match_expr_like_matches_macro.rs:28:15
+  --> $DIR/match_expr_like_matches_macro.rs:29:15
    |
 LL |       let _zz = match x {
    |  _______________^
@@ -43,13 +43,13 @@ LL | |     };
    | |_____^ help: try this: `!matches!(x, Some(r) if r == 0)`
 
 error: if let .. else expression looks like `matches!` macro
-  --> $DIR/match_expr_like_matches_macro.rs:34:16
+  --> $DIR/match_expr_like_matches_macro.rs:35:16
    |
 LL |     let _zzz = if let Some(5) = x { true } else { false };
    |                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `matches!(x, Some(5))`
 
 error: match expression looks like `matches!` macro
-  --> $DIR/match_expr_like_matches_macro.rs:58:20
+  --> $DIR/match_expr_like_matches_macro.rs:59:20
    |
 LL |           let _ans = match x {
    |  ____________________^
@@ -60,7 +60,7 @@ LL | |         };
    | |_________^ help: try this: `matches!(x, E::A(_) | E::B(_))`
 
 error: match expression looks like `matches!` macro
-  --> $DIR/match_expr_like_matches_macro.rs:68:20
+  --> $DIR/match_expr_like_matches_macro.rs:69:20
    |
 LL |           let _ans = match x {
    |  ____________________^
@@ -73,7 +73,7 @@ LL | |         };
    | |_________^ help: try this: `matches!(x, E::A(_) | E::B(_))`
 
 error: match expression looks like `matches!` macro
-  --> $DIR/match_expr_like_matches_macro.rs:78:20
+  --> $DIR/match_expr_like_matches_macro.rs:79:20
    |
 LL |           let _ans = match x {
    |  ____________________^
@@ -84,7 +84,7 @@ LL | |         };
    | |_________^ help: try this: `!matches!(x, E::B(_) | E::C)`
 
 error: match expression looks like `matches!` macro
-  --> $DIR/match_expr_like_matches_macro.rs:138:18
+  --> $DIR/match_expr_like_matches_macro.rs:139:18
    |
 LL |           let _z = match &z {
    |  __________________^
@@ -94,7 +94,7 @@ LL | |         };
    | |_________^ help: try this: `matches!(z, Some(3))`
 
 error: match expression looks like `matches!` macro
-  --> $DIR/match_expr_like_matches_macro.rs:147:18
+  --> $DIR/match_expr_like_matches_macro.rs:148:18
    |
 LL |           let _z = match &z {
    |  __________________^
@@ -104,7 +104,7 @@ LL | |         };
    | |_________^ help: try this: `matches!(&z, Some(3))`
 
 error: match expression looks like `matches!` macro
-  --> $DIR/match_expr_like_matches_macro.rs:164:21
+  --> $DIR/match_expr_like_matches_macro.rs:165:21
    |
 LL |               let _ = match &z {
    |  _____________________^
@@ -114,7 +114,7 @@ LL | |             };
    | |_____________^ help: try this: `matches!(&z, AnEnum::X)`
 
 error: match expression looks like `matches!` macro
-  --> $DIR/match_expr_like_matches_macro.rs:178:20
+  --> $DIR/match_expr_like_matches_macro.rs:179:20
    |
 LL |           let _res = match &val {
    |  ____________________^
@@ -124,7 +124,7 @@ LL | |         };
    | |_________^ help: try this: `matches!(&val, &Some(ref _a))`
 
 error: match expression looks like `matches!` macro
-  --> $DIR/match_expr_like_matches_macro.rs:190:20
+  --> $DIR/match_expr_like_matches_macro.rs:191:20
    |
 LL |           let _res = match &val {
    |  ____________________^
@@ -133,5 +133,15 @@ LL | |             _ => false,
 LL | |         };
    | |_________^ help: try this: `matches!(&val, &Some(ref _a))`
 
-error: aborting due to 13 previous errors
+error: match expression looks like `matches!` macro
+  --> $DIR/match_expr_like_matches_macro.rs:251:14
+   |
+LL |       let _y = match Some(5) {
+   |  ______________^
+LL | |         Some(0) => true,
+LL | |         _ => false,
+LL | |     };
+   | |_____^ help: try this: `matches!(Some(5), Some(0))`
+
+error: aborting due to 14 previous errors
 
diff --git a/src/tools/clippy/tests/ui/match_overlapping_arm.rs b/src/tools/clippy/tests/ui/match_overlapping_arm.rs
index 22b04b208f87..b4097fa96045 100644
--- a/src/tools/clippy/tests/ui/match_overlapping_arm.rs
+++ b/src/tools/clippy/tests/ui/match_overlapping_arm.rs
@@ -1,5 +1,4 @@
 #![feature(exclusive_range_pattern)]
-
 #![warn(clippy::match_overlapping_arm)]
 #![allow(clippy::redundant_pattern_matching)]
 #![allow(clippy::if_same_then_else, clippy::equatable_if_let)]
diff --git a/src/tools/clippy/tests/ui/match_overlapping_arm.stderr b/src/tools/clippy/tests/ui/match_overlapping_arm.stderr
index a72becbeb669..b98d4799e42c 100644
--- a/src/tools/clippy/tests/ui/match_overlapping_arm.stderr
+++ b/src/tools/clippy/tests/ui/match_overlapping_arm.stderr
@@ -1,96 +1,96 @@
 error: some ranges overlap
-  --> $DIR/match_overlapping_arm.rs:13:9
+  --> $DIR/match_overlapping_arm.rs:12:9
    |
 LL |         0..=10 => println!("0..=10"),
    |         ^^^^^^
    |
 note: overlaps with this
-  --> $DIR/match_overlapping_arm.rs:14:9
+  --> $DIR/match_overlapping_arm.rs:13:9
    |
 LL |         0..=11 => println!("0..=11"),
    |         ^^^^^^
    = note: `-D clippy::match-overlapping-arm` implied by `-D warnings`
 
 error: some ranges overlap
-  --> $DIR/match_overlapping_arm.rs:19:9
+  --> $DIR/match_overlapping_arm.rs:18:9
    |
 LL |         0..=5 => println!("0..=5"),
    |         ^^^^^
    |
 note: overlaps with this
-  --> $DIR/match_overlapping_arm.rs:21:9
+  --> $DIR/match_overlapping_arm.rs:20:9
    |
 LL |         FOO..=11 => println!("FOO..=11"),
    |         ^^^^^^^^
 
 error: some ranges overlap
-  --> $DIR/match_overlapping_arm.rs:56:9
+  --> $DIR/match_overlapping_arm.rs:55:9
    |
 LL |         0..11 => println!("0..11"),
    |         ^^^^^
    |
 note: overlaps with this
-  --> $DIR/match_overlapping_arm.rs:57:9
+  --> $DIR/match_overlapping_arm.rs:56:9
    |
 LL |         0..=11 => println!("0..=11"),
    |         ^^^^^^
 
 error: some ranges overlap
-  --> $DIR/match_overlapping_arm.rs:81:9
+  --> $DIR/match_overlapping_arm.rs:80:9
    |
 LL |         0..=10 => println!("0..=10"),
    |         ^^^^^^
    |
 note: overlaps with this
-  --> $DIR/match_overlapping_arm.rs:80:9
+  --> $DIR/match_overlapping_arm.rs:79:9
    |
 LL |         5..14 => println!("5..14"),
    |         ^^^^^
 
 error: some ranges overlap
-  --> $DIR/match_overlapping_arm.rs:86:9
+  --> $DIR/match_overlapping_arm.rs:85:9
    |
 LL |         0..7 => println!("0..7"),
    |         ^^^^
    |
 note: overlaps with this
-  --> $DIR/match_overlapping_arm.rs:87:9
+  --> $DIR/match_overlapping_arm.rs:86:9
    |
 LL |         0..=10 => println!("0..=10"),
    |         ^^^^^^
 
 error: some ranges overlap
-  --> $DIR/match_overlapping_arm.rs:98:9
+  --> $DIR/match_overlapping_arm.rs:97:9
    |
 LL |         ..=23 => println!("..=23"),
    |         ^^^^^
    |
 note: overlaps with this
-  --> $DIR/match_overlapping_arm.rs:99:9
+  --> $DIR/match_overlapping_arm.rs:98:9
    |
 LL |         ..26 => println!("..26"),
    |         ^^^^
 
 error: some ranges overlap
-  --> $DIR/match_overlapping_arm.rs:107:9
+  --> $DIR/match_overlapping_arm.rs:106:9
    |
 LL |         21..=30 => (),
    |         ^^^^^^^
    |
 note: overlaps with this
-  --> $DIR/match_overlapping_arm.rs:108:9
+  --> $DIR/match_overlapping_arm.rs:107:9
    |
 LL |         21..=40 => (),
    |         ^^^^^^^
 
 error: some ranges overlap
-  --> $DIR/match_overlapping_arm.rs:121:9
+  --> $DIR/match_overlapping_arm.rs:120:9
    |
 LL |         0..=0x0000_0000_0000_00ff => (),
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^
    |
 note: overlaps with this
-  --> $DIR/match_overlapping_arm.rs:122:9
+  --> $DIR/match_overlapping_arm.rs:121:9
    |
 LL |         0..=0x0000_0000_0000_ffff => (),
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/src/tools/clippy/tests/ui/match_single_binding.fixed b/src/tools/clippy/tests/ui/match_single_binding.fixed
index 951f552eb32b..a6e315e4773a 100644
--- a/src/tools/clippy/tests/ui/match_single_binding.fixed
+++ b/src/tools/clippy/tests/ui/match_single_binding.fixed
@@ -124,3 +124,12 @@ fn issue_8723() {
 
     let _ = val;
 }
+
+#[allow(dead_code)]
+fn issue_9575() {
+    fn side_effects() {}
+    let _ = || {
+        side_effects();
+        println!("Needs curlies");
+    };
+}
diff --git a/src/tools/clippy/tests/ui/match_single_binding.rs b/src/tools/clippy/tests/ui/match_single_binding.rs
index 19c0fee8fd68..cecbd703e566 100644
--- a/src/tools/clippy/tests/ui/match_single_binding.rs
+++ b/src/tools/clippy/tests/ui/match_single_binding.rs
@@ -140,3 +140,11 @@ fn issue_8723() {
 
     let _ = val;
 }
+
+#[allow(dead_code)]
+fn issue_9575() {
+    fn side_effects() {}
+    let _ = || match side_effects() {
+        _ => println!("Needs curlies"),
+    };
+}
diff --git a/src/tools/clippy/tests/ui/match_single_binding.stderr b/src/tools/clippy/tests/ui/match_single_binding.stderr
index 5d4e7314b213..2b9ec7ee7026 100644
--- a/src/tools/clippy/tests/ui/match_single_binding.stderr
+++ b/src/tools/clippy/tests/ui/match_single_binding.stderr
@@ -196,5 +196,22 @@ LL +         suf
 LL ~     };
    |
 
-error: aborting due to 13 previous errors
+error: this match could be replaced by its scrutinee and body
+  --> $DIR/match_single_binding.rs:147:16
+   |
+LL |       let _ = || match side_effects() {
+   |  ________________^
+LL | |         _ => println!("Needs curlies"),
+LL | |     };
+   | |_____^
+   |
+help: consider using the scrutinee and body instead
+   |
+LL ~     let _ = || {
+LL +         side_effects();
+LL +         println!("Needs curlies");
+LL ~     };
+   |
+
+error: aborting due to 14 previous errors
 
diff --git a/src/tools/clippy/tests/ui/match_wild_err_arm.edition2018.stderr b/src/tools/clippy/tests/ui/match_wild_err_arm.edition2018.stderr
deleted file mode 100644
index 525533bf07bb..000000000000
--- a/src/tools/clippy/tests/ui/match_wild_err_arm.edition2018.stderr
+++ /dev/null
@@ -1,35 +0,0 @@
-error: `Err(_)` matches all errors
-  --> $DIR/match_wild_err_arm.rs:14:9
-   |
-LL |         Err(_) => panic!("err"),
-   |         ^^^^^^
-   |
-   = note: match each error separately or use the error output, or use `.expect(msg)` if the error case is unreachable
-   = note: `-D clippy::match-wild-err-arm` implied by `-D warnings`
-
-error: `Err(_)` matches all errors
-  --> $DIR/match_wild_err_arm.rs:20:9
-   |
-LL |         Err(_) => panic!(),
-   |         ^^^^^^
-   |
-   = note: match each error separately or use the error output, or use `.expect(msg)` if the error case is unreachable
-
-error: `Err(_)` matches all errors
-  --> $DIR/match_wild_err_arm.rs:26:9
-   |
-LL |         Err(_) => {
-   |         ^^^^^^
-   |
-   = note: match each error separately or use the error output, or use `.expect(msg)` if the error case is unreachable
-
-error: `Err(_e)` matches all errors
-  --> $DIR/match_wild_err_arm.rs:34:9
-   |
-LL |         Err(_e) => panic!(),
-   |         ^^^^^^^
-   |
-   = note: match each error separately or use the error output, or use `.expect(msg)` if the error case is unreachable
-
-error: aborting due to 4 previous errors
-
diff --git a/src/tools/clippy/tests/ui/match_wild_err_arm.rs b/src/tools/clippy/tests/ui/match_wild_err_arm.rs
index 0a86144b95d5..823be65efe06 100644
--- a/src/tools/clippy/tests/ui/match_wild_err_arm.rs
+++ b/src/tools/clippy/tests/ui/match_wild_err_arm.rs
@@ -1,6 +1,3 @@
-// revisions: edition2018 edition2021
-// [edition2018] edition:2018
-// [edition2021] edition:2021
 #![feature(exclusive_range_pattern)]
 #![allow(clippy::match_same_arms)]
 #![warn(clippy::match_wild_err_arm)]
diff --git a/src/tools/clippy/tests/ui/match_wild_err_arm.edition2021.stderr b/src/tools/clippy/tests/ui/match_wild_err_arm.stderr
similarity index 86%
rename from src/tools/clippy/tests/ui/match_wild_err_arm.edition2021.stderr
rename to src/tools/clippy/tests/ui/match_wild_err_arm.stderr
index 525533bf07bb..b016d682698c 100644
--- a/src/tools/clippy/tests/ui/match_wild_err_arm.edition2021.stderr
+++ b/src/tools/clippy/tests/ui/match_wild_err_arm.stderr
@@ -1,5 +1,5 @@
 error: `Err(_)` matches all errors
-  --> $DIR/match_wild_err_arm.rs:14:9
+  --> $DIR/match_wild_err_arm.rs:11:9
    |
 LL |         Err(_) => panic!("err"),
    |         ^^^^^^
@@ -8,7 +8,7 @@ LL |         Err(_) => panic!("err"),
    = note: `-D clippy::match-wild-err-arm` implied by `-D warnings`
 
 error: `Err(_)` matches all errors
-  --> $DIR/match_wild_err_arm.rs:20:9
+  --> $DIR/match_wild_err_arm.rs:17:9
    |
 LL |         Err(_) => panic!(),
    |         ^^^^^^
@@ -16,7 +16,7 @@ LL |         Err(_) => panic!(),
    = note: match each error separately or use the error output, or use `.expect(msg)` if the error case is unreachable
 
 error: `Err(_)` matches all errors
-  --> $DIR/match_wild_err_arm.rs:26:9
+  --> $DIR/match_wild_err_arm.rs:23:9
    |
 LL |         Err(_) => {
    |         ^^^^^^
@@ -24,7 +24,7 @@ LL |         Err(_) => {
    = note: match each error separately or use the error output, or use `.expect(msg)` if the error case is unreachable
 
 error: `Err(_e)` matches all errors
-  --> $DIR/match_wild_err_arm.rs:34:9
+  --> $DIR/match_wild_err_arm.rs:31:9
    |
 LL |         Err(_e) => panic!(),
    |         ^^^^^^^
diff --git a/src/tools/clippy/tests/ui/mem_replace.fixed b/src/tools/clippy/tests/ui/mem_replace.fixed
index b609ba659467..ae237395b95f 100644
--- a/src/tools/clippy/tests/ui/mem_replace.fixed
+++ b/src/tools/clippy/tests/ui/mem_replace.fixed
@@ -1,5 +1,7 @@
 // run-rustfix
-#![allow(unused_imports)]
+
+#![feature(custom_inner_attributes)]
+#![allow(unused)]
 #![warn(
     clippy::all,
     clippy::style,
@@ -77,3 +79,17 @@ fn main() {
     replace_with_default();
     dont_lint_primitive();
 }
+
+fn msrv_1_39() {
+    #![clippy::msrv = "1.39"]
+
+    let mut s = String::from("foo");
+    let _ = std::mem::replace(&mut s, String::default());
+}
+
+fn msrv_1_40() {
+    #![clippy::msrv = "1.40"]
+
+    let mut s = String::from("foo");
+    let _ = std::mem::take(&mut s);
+}
diff --git a/src/tools/clippy/tests/ui/mem_replace.rs b/src/tools/clippy/tests/ui/mem_replace.rs
index 93f6dcdec83b..3202e99e0be9 100644
--- a/src/tools/clippy/tests/ui/mem_replace.rs
+++ b/src/tools/clippy/tests/ui/mem_replace.rs
@@ -1,5 +1,7 @@
 // run-rustfix
-#![allow(unused_imports)]
+
+#![feature(custom_inner_attributes)]
+#![allow(unused)]
 #![warn(
     clippy::all,
     clippy::style,
@@ -77,3 +79,17 @@ fn main() {
     replace_with_default();
     dont_lint_primitive();
 }
+
+fn msrv_1_39() {
+    #![clippy::msrv = "1.39"]
+
+    let mut s = String::from("foo");
+    let _ = std::mem::replace(&mut s, String::default());
+}
+
+fn msrv_1_40() {
+    #![clippy::msrv = "1.40"]
+
+    let mut s = String::from("foo");
+    let _ = std::mem::replace(&mut s, String::default());
+}
diff --git a/src/tools/clippy/tests/ui/mem_replace.stderr b/src/tools/clippy/tests/ui/mem_replace.stderr
index 90dc6c95f858..dd8a50dab900 100644
--- a/src/tools/clippy/tests/ui/mem_replace.stderr
+++ b/src/tools/clippy/tests/ui/mem_replace.stderr
@@ -1,5 +1,5 @@
 error: replacing an `Option` with `None`
-  --> $DIR/mem_replace.rs:15:13
+  --> $DIR/mem_replace.rs:17:13
    |
 LL |     let _ = mem::replace(&mut an_option, None);
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider `Option::take()` instead: `an_option.take()`
@@ -7,13 +7,13 @@ LL |     let _ = mem::replace(&mut an_option, None);
    = note: `-D clippy::mem-replace-option-with-none` implied by `-D warnings`
 
 error: replacing an `Option` with `None`
-  --> $DIR/mem_replace.rs:17:13
+  --> $DIR/mem_replace.rs:19:13
    |
 LL |     let _ = mem::replace(an_option, None);
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider `Option::take()` instead: `an_option.take()`
 
 error: replacing a value of type `T` with `T::default()` is better expressed using `std::mem::take`
-  --> $DIR/mem_replace.rs:22:13
+  --> $DIR/mem_replace.rs:24:13
    |
 LL |     let _ = std::mem::replace(&mut s, String::default());
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `std::mem::take(&mut s)`
@@ -21,100 +21,106 @@ LL |     let _ = std::mem::replace(&mut s, String::default());
    = note: `-D clippy::mem-replace-with-default` implied by `-D warnings`
 
 error: replacing a value of type `T` with `T::default()` is better expressed using `std::mem::take`
-  --> $DIR/mem_replace.rs:25:13
+  --> $DIR/mem_replace.rs:27:13
    |
 LL |     let _ = std::mem::replace(s, String::default());
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `std::mem::take(s)`
 
 error: replacing a value of type `T` with `T::default()` is better expressed using `std::mem::take`
-  --> $DIR/mem_replace.rs:26:13
+  --> $DIR/mem_replace.rs:28:13
    |
 LL |     let _ = std::mem::replace(s, Default::default());
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `std::mem::take(s)`
 
 error: replacing a value of type `T` with `T::default()` is better expressed using `std::mem::take`
-  --> $DIR/mem_replace.rs:29:13
+  --> $DIR/mem_replace.rs:31:13
    |
 LL |     let _ = std::mem::replace(&mut v, Vec::default());
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `std::mem::take(&mut v)`
 
 error: replacing a value of type `T` with `T::default()` is better expressed using `std::mem::take`
-  --> $DIR/mem_replace.rs:30:13
+  --> $DIR/mem_replace.rs:32:13
    |
 LL |     let _ = std::mem::replace(&mut v, Default::default());
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `std::mem::take(&mut v)`
 
 error: replacing a value of type `T` with `T::default()` is better expressed using `std::mem::take`
-  --> $DIR/mem_replace.rs:31:13
+  --> $DIR/mem_replace.rs:33:13
    |
 LL |     let _ = std::mem::replace(&mut v, Vec::new());
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `std::mem::take(&mut v)`
 
 error: replacing a value of type `T` with `T::default()` is better expressed using `std::mem::take`
-  --> $DIR/mem_replace.rs:32:13
+  --> $DIR/mem_replace.rs:34:13
    |
 LL |     let _ = std::mem::replace(&mut v, vec![]);
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `std::mem::take(&mut v)`
 
 error: replacing a value of type `T` with `T::default()` is better expressed using `std::mem::take`
-  --> $DIR/mem_replace.rs:35:13
+  --> $DIR/mem_replace.rs:37:13
    |
 LL |     let _ = std::mem::replace(&mut hash_map, HashMap::new());
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `std::mem::take(&mut hash_map)`
 
 error: replacing a value of type `T` with `T::default()` is better expressed using `std::mem::take`
-  --> $DIR/mem_replace.rs:38:13
+  --> $DIR/mem_replace.rs:40:13
    |
 LL |     let _ = std::mem::replace(&mut btree_map, BTreeMap::new());
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `std::mem::take(&mut btree_map)`
 
 error: replacing a value of type `T` with `T::default()` is better expressed using `std::mem::take`
-  --> $DIR/mem_replace.rs:41:13
+  --> $DIR/mem_replace.rs:43:13
    |
 LL |     let _ = std::mem::replace(&mut vd, VecDeque::new());
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `std::mem::take(&mut vd)`
 
 error: replacing a value of type `T` with `T::default()` is better expressed using `std::mem::take`
-  --> $DIR/mem_replace.rs:44:13
+  --> $DIR/mem_replace.rs:46:13
    |
 LL |     let _ = std::mem::replace(&mut hash_set, HashSet::new());
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `std::mem::take(&mut hash_set)`
 
 error: replacing a value of type `T` with `T::default()` is better expressed using `std::mem::take`
-  --> $DIR/mem_replace.rs:47:13
+  --> $DIR/mem_replace.rs:49:13
    |
 LL |     let _ = std::mem::replace(&mut btree_set, BTreeSet::new());
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `std::mem::take(&mut btree_set)`
 
 error: replacing a value of type `T` with `T::default()` is better expressed using `std::mem::take`
-  --> $DIR/mem_replace.rs:50:13
+  --> $DIR/mem_replace.rs:52:13
    |
 LL |     let _ = std::mem::replace(&mut list, LinkedList::new());
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `std::mem::take(&mut list)`
 
 error: replacing a value of type `T` with `T::default()` is better expressed using `std::mem::take`
-  --> $DIR/mem_replace.rs:53:13
+  --> $DIR/mem_replace.rs:55:13
    |
 LL |     let _ = std::mem::replace(&mut binary_heap, BinaryHeap::new());
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `std::mem::take(&mut binary_heap)`
 
 error: replacing a value of type `T` with `T::default()` is better expressed using `std::mem::take`
-  --> $DIR/mem_replace.rs:56:13
+  --> $DIR/mem_replace.rs:58:13
    |
 LL |     let _ = std::mem::replace(&mut tuple, (vec![], BinaryHeap::new()));
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `std::mem::take(&mut tuple)`
 
 error: replacing a value of type `T` with `T::default()` is better expressed using `std::mem::take`
-  --> $DIR/mem_replace.rs:59:13
+  --> $DIR/mem_replace.rs:61:13
    |
 LL |     let _ = std::mem::replace(&mut refstr, "");
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `std::mem::take(&mut refstr)`
 
 error: replacing a value of type `T` with `T::default()` is better expressed using `std::mem::take`
-  --> $DIR/mem_replace.rs:62:13
+  --> $DIR/mem_replace.rs:64:13
    |
 LL |     let _ = std::mem::replace(&mut slice, &[]);
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `std::mem::take(&mut slice)`
 
-error: aborting due to 19 previous errors
+error: replacing a value of type `T` with `T::default()` is better expressed using `std::mem::take`
+  --> $DIR/mem_replace.rs:94:13
+   |
+LL |     let _ = std::mem::replace(&mut s, String::default());
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `std::mem::take(&mut s)`
+
+error: aborting due to 20 previous errors
 
diff --git a/src/tools/clippy/tests/ui/min_rust_version_attr.rs b/src/tools/clippy/tests/ui/min_rust_version_attr.rs
index c4c6391bb4c1..cd148063bf06 100644
--- a/src/tools/clippy/tests/ui/min_rust_version_attr.rs
+++ b/src/tools/clippy/tests/ui/min_rust_version_attr.rs
@@ -1,240 +1,29 @@
 #![allow(clippy::redundant_clone)]
 #![feature(custom_inner_attributes)]
-#![clippy::msrv = "1.0.0"]
 
-use std::ops::{Deref, RangeFrom};
+fn main() {}
 
-fn approx_const() {
+fn just_under_msrv() {
+    #![clippy::msrv = "1.42.0"]
     let log2_10 = 3.321928094887362;
-    let log10_2 = 0.301029995663981;
 }
 
-fn cloned_instead_of_copied() {
-    let _ = [1].iter().cloned();
+fn meets_msrv() {
+    #![clippy::msrv = "1.43.0"]
+    let log2_10 = 3.321928094887362;
 }
 
-fn option_as_ref_deref() {
-    let mut opt = Some(String::from("123"));
-
-    let _ = opt.as_ref().map(String::as_str);
-    let _ = opt.as_ref().map(|x| x.as_str());
-    let _ = opt.as_mut().map(String::as_mut_str);
-    let _ = opt.as_mut().map(|x| x.as_mut_str());
-}
-
-fn match_like_matches() {
-    let _y = match Some(5) {
-        Some(0) => true,
-        _ => false,
-    };
-}
-
-fn match_same_arms() {
-    match (1, 2, 3) {
-        (1, .., 3) => 42,
-        (.., 3) => 42, //~ ERROR match arms have same body
-        _ => 0,
-    };
-}
-
-fn match_same_arms2() {
-    let _ = match Some(42) {
-        Some(_) => 24,
-        None => 24, //~ ERROR match arms have same body
-    };
-}
-
-pub fn manual_strip_msrv() {
-    let s = "hello, world!";
-    if s.starts_with("hello, ") {
-        assert_eq!(s["hello, ".len()..].to_uppercase(), "WORLD!");
-    }
-}
-
-pub fn redundant_fieldnames() {
-    let start = 0;
-    let _ = RangeFrom { start: start };
-}
-
-pub fn redundant_static_lifetime() {
-    const VAR_ONE: &'static str = "Test constant #1";
-}
-
-pub fn checked_conversion() {
-    let value: i64 = 42;
-    let _ = value <= (u32::max_value() as i64) && value >= 0;
-    let _ = value <= (u32::MAX as i64) && value >= 0;
-}
-
-pub struct FromOverInto(String);
-
-impl Into<FromOverInto> for String {
-    fn into(self) -> FromOverInto {
-        FromOverInto(self)
-    }
-}
-
-pub fn filter_map_next() {
-    let a = ["1", "lol", "3", "NaN", "5"];
-
-    #[rustfmt::skip]
-    let _: Option<u32> = vec![1, 2, 3, 4, 5, 6]
-        .into_iter()
-        .filter_map(|x| {
-            if x == 2 {
-                Some(x * 2)
-            } else {
-                None
-            }
-        })
-        .next();
-}
-
-#[allow(clippy::no_effect)]
-#[allow(clippy::short_circuit_statement)]
-#[allow(clippy::unnecessary_operation)]
-pub fn manual_range_contains() {
-    let x = 5;
-    x >= 8 && x < 12;
-}
-
-pub fn use_self() {
-    struct Foo;
-
-    impl Foo {
-        fn new() -> Foo {
-            Foo {}
-        }
-        fn test() -> Foo {
-            Foo::new()
-        }
-    }
-}
-
-fn replace_with_default() {
-    let mut s = String::from("foo");
-    let _ = std::mem::replace(&mut s, String::default());
-}
-
-fn map_unwrap_or() {
-    let opt = Some(1);
-
-    // Check for `option.map(_).unwrap_or(_)` use.
-    // Single line case.
-    let _ = opt
-        .map(|x| x + 1)
-        // Should lint even though this call is on a separate line.
-        .unwrap_or(0);
-}
-
-// Could be const
-fn missing_const_for_fn() -> i32 {
-    1
-}
-
-fn unnest_or_patterns() {
-    struct TS(u8, u8);
-    if let TS(0, x) | TS(1, x) = TS(0, 0) {}
-}
-
-#[cfg_attr(rustfmt, rustfmt_skip)]
-fn deprecated_cfg_attr() {}
-
-#[warn(clippy::cast_lossless)]
-fn int_from_bool() -> u8 {
-    true as u8
-}
-
-fn err_expect() {
-    let x: Result<u32, &str> = Ok(10);
-    x.err().expect("Testing expect_err");
-}
-
-fn cast_abs_to_unsigned() {
-    let x: i32 = 10;
-    assert_eq!(10u32, x.abs() as u32);
-}
-
-fn manual_rem_euclid() {
-    let x: i32 = 10;
-    let _: i32 = ((x % 4) + 4) % 4;
-}
-
-fn manual_clamp() {
-    let (input, min, max) = (0, -1, 2);
-    let _ = if input < min {
-        min
-    } else if input > max {
-        max
-    } else {
-        input
-    };
-}
-
-fn main() {
-    filter_map_next();
-    checked_conversion();
-    redundant_fieldnames();
-    redundant_static_lifetime();
-    option_as_ref_deref();
-    match_like_matches();
-    match_same_arms();
-    match_same_arms2();
-    manual_strip_msrv();
-    manual_range_contains();
-    use_self();
-    replace_with_default();
-    map_unwrap_or();
-    missing_const_for_fn();
-    unnest_or_patterns();
-    int_from_bool();
-    err_expect();
-    cast_abs_to_unsigned();
-    manual_rem_euclid();
-    manual_clamp();
-}
-
-mod just_under_msrv {
-    #![feature(custom_inner_attributes)]
+fn just_above_msrv() {
     #![clippy::msrv = "1.44.0"]
-
-    fn main() {
-        let s = "hello, world!";
-        if s.starts_with("hello, ") {
-            assert_eq!(s["hello, ".len()..].to_uppercase(), "WORLD!");
-        }
-    }
+    let log2_10 = 3.321928094887362;
 }
 
-mod meets_msrv {
-    #![feature(custom_inner_attributes)]
-    #![clippy::msrv = "1.45.0"]
-
-    fn main() {
-        let s = "hello, world!";
-        if s.starts_with("hello, ") {
-            assert_eq!(s["hello, ".len()..].to_uppercase(), "WORLD!");
-        }
-    }
+fn no_patch_under() {
+    #![clippy::msrv = "1.42"]
+    let log2_10 = 3.321928094887362;
 }
 
-mod just_above_msrv {
-    #![feature(custom_inner_attributes)]
-    #![clippy::msrv = "1.46.0"]
-
-    fn main() {
-        let s = "hello, world!";
-        if s.starts_with("hello, ") {
-            assert_eq!(s["hello, ".len()..].to_uppercase(), "WORLD!");
-        }
-    }
-}
-
-mod const_rem_euclid {
-    #![feature(custom_inner_attributes)]
-    #![clippy::msrv = "1.50.0"]
-
-    pub const fn const_rem_euclid_4(num: i32) -> i32 {
-        ((num % 4) + 4) % 4
-    }
+fn no_patch_meets() {
+    #![clippy::msrv = "1.43"]
+    let log2_10 = 3.321928094887362;
 }
diff --git a/src/tools/clippy/tests/ui/min_rust_version_attr.stderr b/src/tools/clippy/tests/ui/min_rust_version_attr.stderr
index d1cffc26a831..68aa58748190 100644
--- a/src/tools/clippy/tests/ui/min_rust_version_attr.stderr
+++ b/src/tools/clippy/tests/ui/min_rust_version_attr.stderr
@@ -1,37 +1,27 @@
-error: stripping a prefix manually
-  --> $DIR/min_rust_version_attr.rs:216:24
+error: approximate value of `f{32, 64}::consts::LOG2_10` found
+  --> $DIR/min_rust_version_attr.rs:13:19
    |
-LL |             assert_eq!(s["hello, ".len()..].to_uppercase(), "WORLD!");
-   |                        ^^^^^^^^^^^^^^^^^^^^
-   |
-note: the prefix was tested here
-  --> $DIR/min_rust_version_attr.rs:215:9
-   |
-LL |         if s.starts_with("hello, ") {
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   = note: `-D clippy::manual-strip` implied by `-D warnings`
-help: try using the `strip_prefix` method
-   |
-LL ~         if let Some(<stripped>) = s.strip_prefix("hello, ") {
-LL ~             assert_eq!(<stripped>.to_uppercase(), "WORLD!");
+LL |     let log2_10 = 3.321928094887362;
+   |                   ^^^^^^^^^^^^^^^^^
    |
+   = help: consider using the constant directly
+   = note: `#[deny(clippy::approx_constant)]` on by default
 
-error: stripping a prefix manually
-  --> $DIR/min_rust_version_attr.rs:228:24
+error: approximate value of `f{32, 64}::consts::LOG2_10` found
+  --> $DIR/min_rust_version_attr.rs:18:19
    |
-LL |             assert_eq!(s["hello, ".len()..].to_uppercase(), "WORLD!");
-   |                        ^^^^^^^^^^^^^^^^^^^^
-   |
-note: the prefix was tested here
-  --> $DIR/min_rust_version_attr.rs:227:9
-   |
-LL |         if s.starts_with("hello, ") {
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-help: try using the `strip_prefix` method
-   |
-LL ~         if let Some(<stripped>) = s.strip_prefix("hello, ") {
-LL ~             assert_eq!(<stripped>.to_uppercase(), "WORLD!");
+LL |     let log2_10 = 3.321928094887362;
+   |                   ^^^^^^^^^^^^^^^^^
    |
+   = help: consider using the constant directly
 
-error: aborting due to 2 previous errors
+error: approximate value of `f{32, 64}::consts::LOG2_10` found
+  --> $DIR/min_rust_version_attr.rs:28:19
+   |
+LL |     let log2_10 = 3.321928094887362;
+   |                   ^^^^^^^^^^^^^^^^^
+   |
+   = help: consider using the constant directly
+
+error: aborting due to 3 previous errors
 
diff --git a/src/tools/clippy/tests/ui/min_rust_version_invalid_attr.rs b/src/tools/clippy/tests/ui/min_rust_version_invalid_attr.rs
index f20841891a74..02892f329af6 100644
--- a/src/tools/clippy/tests/ui/min_rust_version_invalid_attr.rs
+++ b/src/tools/clippy/tests/ui/min_rust_version_invalid_attr.rs
@@ -2,3 +2,17 @@
 #![clippy::msrv = "invalid.version"]
 
 fn main() {}
+
+#[clippy::msrv = "invalid.version"]
+fn outer_attr() {}
+
+mod multiple {
+    #![clippy::msrv = "1.40"]
+    #![clippy::msrv = "=1.35.0"]
+    #![clippy::msrv = "1.10.1"]
+
+    mod foo {
+        #![clippy::msrv = "1"]
+        #![clippy::msrv = "1.0.0"]
+    }
+}
diff --git a/src/tools/clippy/tests/ui/min_rust_version_invalid_attr.stderr b/src/tools/clippy/tests/ui/min_rust_version_invalid_attr.stderr
index 6ff88ca56f8b..93370a0fa9c9 100644
--- a/src/tools/clippy/tests/ui/min_rust_version_invalid_attr.stderr
+++ b/src/tools/clippy/tests/ui/min_rust_version_invalid_attr.stderr
@@ -4,5 +4,47 @@ error: `invalid.version` is not a valid Rust version
 LL | #![clippy::msrv = "invalid.version"]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: aborting due to previous error
+error: `msrv` cannot be an outer attribute
+  --> $DIR/min_rust_version_invalid_attr.rs:6:1
+   |
+LL | #[clippy::msrv = "invalid.version"]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: `msrv` is defined multiple times
+  --> $DIR/min_rust_version_invalid_attr.rs:11:5
+   |
+LL |     #![clippy::msrv = "=1.35.0"]
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+note: first definition found here
+  --> $DIR/min_rust_version_invalid_attr.rs:10:5
+   |
+LL |     #![clippy::msrv = "1.40"]
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: `msrv` is defined multiple times
+  --> $DIR/min_rust_version_invalid_attr.rs:12:5
+   |
+LL |     #![clippy::msrv = "1.10.1"]
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+note: first definition found here
+  --> $DIR/min_rust_version_invalid_attr.rs:10:5
+   |
+LL |     #![clippy::msrv = "1.40"]
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: `msrv` is defined multiple times
+  --> $DIR/min_rust_version_invalid_attr.rs:16:9
+   |
+LL |         #![clippy::msrv = "1.0.0"]
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+note: first definition found here
+  --> $DIR/min_rust_version_invalid_attr.rs:15:9
+   |
+LL |         #![clippy::msrv = "1"]
+   |         ^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to 5 previous errors
 
diff --git a/src/tools/clippy/tests/ui/min_rust_version_multiple_inner_attr.rs b/src/tools/clippy/tests/ui/min_rust_version_multiple_inner_attr.rs
deleted file mode 100644
index e882d5ccf91a..000000000000
--- a/src/tools/clippy/tests/ui/min_rust_version_multiple_inner_attr.rs
+++ /dev/null
@@ -1,11 +0,0 @@
-#![feature(custom_inner_attributes)]
-#![clippy::msrv = "1.40"]
-#![clippy::msrv = "=1.35.0"]
-#![clippy::msrv = "1.10.1"]
-
-mod foo {
-    #![clippy::msrv = "1"]
-    #![clippy::msrv = "1.0.0"]
-}
-
-fn main() {}
diff --git a/src/tools/clippy/tests/ui/min_rust_version_multiple_inner_attr.stderr b/src/tools/clippy/tests/ui/min_rust_version_multiple_inner_attr.stderr
deleted file mode 100644
index e3ff6605cde8..000000000000
--- a/src/tools/clippy/tests/ui/min_rust_version_multiple_inner_attr.stderr
+++ /dev/null
@@ -1,38 +0,0 @@
-error: `msrv` is defined multiple times
-  --> $DIR/min_rust_version_multiple_inner_attr.rs:3:1
-   |
-LL | #![clippy::msrv = "=1.35.0"]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-note: first definition found here
-  --> $DIR/min_rust_version_multiple_inner_attr.rs:2:1
-   |
-LL | #![clippy::msrv = "1.40"]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^
-
-error: `msrv` is defined multiple times
-  --> $DIR/min_rust_version_multiple_inner_attr.rs:4:1
-   |
-LL | #![clippy::msrv = "1.10.1"]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-note: first definition found here
-  --> $DIR/min_rust_version_multiple_inner_attr.rs:2:1
-   |
-LL | #![clippy::msrv = "1.40"]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^
-
-error: `msrv` is defined multiple times
-  --> $DIR/min_rust_version_multiple_inner_attr.rs:8:5
-   |
-LL |     #![clippy::msrv = "1.0.0"]
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-note: first definition found here
-  --> $DIR/min_rust_version_multiple_inner_attr.rs:7:5
-   |
-LL |     #![clippy::msrv = "1"]
-   |     ^^^^^^^^^^^^^^^^^^^^^^
-
-error: aborting due to 3 previous errors
-
diff --git a/src/tools/clippy/tests/ui/min_rust_version_no_patch.rs b/src/tools/clippy/tests/ui/min_rust_version_no_patch.rs
deleted file mode 100644
index 98fffe1e3512..000000000000
--- a/src/tools/clippy/tests/ui/min_rust_version_no_patch.rs
+++ /dev/null
@@ -1,14 +0,0 @@
-#![allow(clippy::redundant_clone)]
-#![feature(custom_inner_attributes)]
-#![clippy::msrv = "1.0"]
-
-fn manual_strip_msrv() {
-    let s = "hello, world!";
-    if s.starts_with("hello, ") {
-        assert_eq!(s["hello, ".len()..].to_uppercase(), "WORLD!");
-    }
-}
-
-fn main() {
-    manual_strip_msrv()
-}
diff --git a/src/tools/clippy/tests/ui/min_rust_version_outer_attr.rs b/src/tools/clippy/tests/ui/min_rust_version_outer_attr.rs
deleted file mode 100644
index 551948bd72ef..000000000000
--- a/src/tools/clippy/tests/ui/min_rust_version_outer_attr.rs
+++ /dev/null
@@ -1,4 +0,0 @@
-#![feature(custom_inner_attributes)]
-
-#[clippy::msrv = "invalid.version"]
-fn main() {}
diff --git a/src/tools/clippy/tests/ui/min_rust_version_outer_attr.stderr b/src/tools/clippy/tests/ui/min_rust_version_outer_attr.stderr
deleted file mode 100644
index 579ee7a87d23..000000000000
--- a/src/tools/clippy/tests/ui/min_rust_version_outer_attr.stderr
+++ /dev/null
@@ -1,8 +0,0 @@
-error: `msrv` cannot be an outer attribute
-  --> $DIR/min_rust_version_outer_attr.rs:3:1
-   |
-LL | #[clippy::msrv = "invalid.version"]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-error: aborting due to previous error
-
diff --git a/src/tools/clippy/tests/ui/missing_const_for_fn/could_be_const.rs b/src/tools/clippy/tests/ui/missing_const_for_fn/could_be_const.rs
index 88f6935d224a..b85e88784918 100644
--- a/src/tools/clippy/tests/ui/missing_const_for_fn/could_be_const.rs
+++ b/src/tools/clippy/tests/ui/missing_const_for_fn/could_be_const.rs
@@ -77,5 +77,17 @@ mod const_fn_stabilized_before_msrv {
     }
 }
 
+fn msrv_1_45() -> i32 {
+    #![clippy::msrv = "1.45"]
+
+    45
+}
+
+fn msrv_1_46() -> i32 {
+    #![clippy::msrv = "1.46"]
+
+    46
+}
+
 // Should not be const
 fn main() {}
diff --git a/src/tools/clippy/tests/ui/missing_const_for_fn/could_be_const.stderr b/src/tools/clippy/tests/ui/missing_const_for_fn/could_be_const.stderr
index 3eb52b682747..f8e221c82f1a 100644
--- a/src/tools/clippy/tests/ui/missing_const_for_fn/could_be_const.stderr
+++ b/src/tools/clippy/tests/ui/missing_const_for_fn/could_be_const.stderr
@@ -81,5 +81,15 @@ LL | |         byte.is_ascii_digit();
 LL | |     }
    | |_____^
 
-error: aborting due to 10 previous errors
+error: this could be a `const fn`
+  --> $DIR/could_be_const.rs:86:1
+   |
+LL | / fn msrv_1_46() -> i32 {
+LL | |     #![clippy::msrv = "1.46"]
+LL | |
+LL | |     46
+LL | | }
+   | |_^
+
+error: aborting due to 11 previous errors
 
diff --git a/src/tools/clippy/tests/ui/missing_trait_methods.rs b/src/tools/clippy/tests/ui/missing_trait_methods.rs
new file mode 100644
index 000000000000..8df885919a3e
--- /dev/null
+++ b/src/tools/clippy/tests/ui/missing_trait_methods.rs
@@ -0,0 +1,50 @@
+#![allow(unused, clippy::needless_lifetimes)]
+#![warn(clippy::missing_trait_methods)]
+
+trait A {
+    fn provided() {}
+}
+
+trait B {
+    fn required();
+
+    fn a(_: usize) -> usize {
+        1
+    }
+
+    fn b<'a, T: AsRef<[u8]>>(a: &'a T) -> &'a [u8] {
+        a.as_ref()
+    }
+}
+
+struct Partial;
+
+impl A for Partial {}
+
+impl B for Partial {
+    fn required() {}
+
+    fn a(_: usize) -> usize {
+        2
+    }
+}
+
+struct Complete;
+
+impl A for Complete {
+    fn provided() {}
+}
+
+impl B for Complete {
+    fn required() {}
+
+    fn a(_: usize) -> usize {
+        2
+    }
+
+    fn b<T: AsRef<[u8]>>(a: &T) -> &[u8] {
+        a.as_ref()
+    }
+}
+
+fn main() {}
diff --git a/src/tools/clippy/tests/ui/missing_trait_methods.stderr b/src/tools/clippy/tests/ui/missing_trait_methods.stderr
new file mode 100644
index 000000000000..0c5205e19657
--- /dev/null
+++ b/src/tools/clippy/tests/ui/missing_trait_methods.stderr
@@ -0,0 +1,27 @@
+error: missing trait method provided by default: `provided`
+  --> $DIR/missing_trait_methods.rs:22:1
+   |
+LL | impl A for Partial {}
+   | ^^^^^^^^^^^^^^^^^^
+   |
+help: implement the method
+  --> $DIR/missing_trait_methods.rs:5:5
+   |
+LL |     fn provided() {}
+   |     ^^^^^^^^^^^^^
+   = note: `-D clippy::missing-trait-methods` implied by `-D warnings`
+
+error: missing trait method provided by default: `b`
+  --> $DIR/missing_trait_methods.rs:24:1
+   |
+LL | impl B for Partial {
+   | ^^^^^^^^^^^^^^^^^^
+   |
+help: implement the method
+  --> $DIR/missing_trait_methods.rs:15:5
+   |
+LL |     fn b<'a, T: AsRef<[u8]>>(a: &'a T) -> &'a [u8] {
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to 2 previous errors
+
diff --git a/src/tools/clippy/tests/ui/needless_borrow.fixed b/src/tools/clippy/tests/ui/needless_borrow.fixed
index aa2687159ef4..340e89d2db1d 100644
--- a/src/tools/clippy/tests/ui/needless_borrow.fixed
+++ b/src/tools/clippy/tests/ui/needless_borrow.fixed
@@ -3,7 +3,11 @@
 
 #[warn(clippy::all, clippy::needless_borrow)]
 #[allow(unused_variables)]
-#[allow(clippy::uninlined_format_args, clippy::unnecessary_mut_passed)]
+#[allow(
+    clippy::uninlined_format_args,
+    clippy::unnecessary_mut_passed,
+    clippy::unnecessary_to_owned
+)]
 fn main() {
     let a = 5;
     let ref_a = &a;
@@ -134,6 +138,7 @@ fn main() {
     multiple_constraints([[""]]);
     multiple_constraints_normalizes_to_same(X, X);
     let _ = Some("").unwrap_or("");
+    let _ = std::fs::write("x", "".to_string());
 
     only_sized(&""); // Don't lint. `Sized` is only bound
     let _ = std::any::Any::type_id(&""); // Don't lint. `Any` is only bound
@@ -276,8 +281,9 @@ mod copyable_iterator {
     fn dont_warn(mut x: Iter) {
         takes_iter(&mut x);
     }
+    #[allow(unused_mut)]
     fn warn(mut x: &mut Iter) {
-        takes_iter(&mut x)
+        takes_iter(x)
     }
 }
 
@@ -327,3 +333,55 @@ fn issue9383() {
         ManuallyDrop::drop(&mut ocean.coral);
     }
 }
+
+#[allow(dead_code)]
+fn closure_test() {
+    let env = "env".to_owned();
+    let arg = "arg".to_owned();
+    let f = |arg| {
+        let loc = "loc".to_owned();
+        let _ = std::fs::write("x", &env); // Don't lint. In environment
+        let _ = std::fs::write("x", arg);
+        let _ = std::fs::write("x", loc);
+    };
+    let _ = std::fs::write("x", &env); // Don't lint. Borrowed by `f`
+    f(arg);
+}
+
+#[allow(dead_code)]
+mod significant_drop {
+    #[derive(Debug)]
+    struct X;
+
+    #[derive(Debug)]
+    struct Y;
+
+    impl Drop for Y {
+        fn drop(&mut self) {}
+    }
+
+    fn foo(x: X, y: Y) {
+        debug(x);
+        debug(&y); // Don't lint. Has significant drop
+    }
+
+    fn debug(_: impl std::fmt::Debug) {}
+}
+
+#[allow(dead_code)]
+mod used_exactly_once {
+    fn foo(x: String) {
+        use_x(x);
+    }
+    fn use_x(_: impl AsRef<str>) {}
+}
+
+#[allow(dead_code)]
+mod used_more_than_once {
+    fn foo(x: String) {
+        use_x(&x);
+        use_x_again(&x);
+    }
+    fn use_x(_: impl AsRef<str>) {}
+    fn use_x_again(_: impl AsRef<str>) {}
+}
diff --git a/src/tools/clippy/tests/ui/needless_borrow.rs b/src/tools/clippy/tests/ui/needless_borrow.rs
index d41251e8f6aa..c93711ac8e28 100644
--- a/src/tools/clippy/tests/ui/needless_borrow.rs
+++ b/src/tools/clippy/tests/ui/needless_borrow.rs
@@ -3,7 +3,11 @@
 
 #[warn(clippy::all, clippy::needless_borrow)]
 #[allow(unused_variables)]
-#[allow(clippy::uninlined_format_args, clippy::unnecessary_mut_passed)]
+#[allow(
+    clippy::uninlined_format_args,
+    clippy::unnecessary_mut_passed,
+    clippy::unnecessary_to_owned
+)]
 fn main() {
     let a = 5;
     let ref_a = &a;
@@ -134,6 +138,7 @@ fn main() {
     multiple_constraints(&[[""]]);
     multiple_constraints_normalizes_to_same(&X, X);
     let _ = Some("").unwrap_or(&"");
+    let _ = std::fs::write("x", &"".to_string());
 
     only_sized(&""); // Don't lint. `Sized` is only bound
     let _ = std::any::Any::type_id(&""); // Don't lint. `Any` is only bound
@@ -276,6 +281,7 @@ mod copyable_iterator {
     fn dont_warn(mut x: Iter) {
         takes_iter(&mut x);
     }
+    #[allow(unused_mut)]
     fn warn(mut x: &mut Iter) {
         takes_iter(&mut x)
     }
@@ -327,3 +333,55 @@ fn issue9383() {
         ManuallyDrop::drop(&mut ocean.coral);
     }
 }
+
+#[allow(dead_code)]
+fn closure_test() {
+    let env = "env".to_owned();
+    let arg = "arg".to_owned();
+    let f = |arg| {
+        let loc = "loc".to_owned();
+        let _ = std::fs::write("x", &env); // Don't lint. In environment
+        let _ = std::fs::write("x", &arg);
+        let _ = std::fs::write("x", &loc);
+    };
+    let _ = std::fs::write("x", &env); // Don't lint. Borrowed by `f`
+    f(arg);
+}
+
+#[allow(dead_code)]
+mod significant_drop {
+    #[derive(Debug)]
+    struct X;
+
+    #[derive(Debug)]
+    struct Y;
+
+    impl Drop for Y {
+        fn drop(&mut self) {}
+    }
+
+    fn foo(x: X, y: Y) {
+        debug(&x);
+        debug(&y); // Don't lint. Has significant drop
+    }
+
+    fn debug(_: impl std::fmt::Debug) {}
+}
+
+#[allow(dead_code)]
+mod used_exactly_once {
+    fn foo(x: String) {
+        use_x(&x);
+    }
+    fn use_x(_: impl AsRef<str>) {}
+}
+
+#[allow(dead_code)]
+mod used_more_than_once {
+    fn foo(x: String) {
+        use_x(&x);
+        use_x_again(&x);
+    }
+    fn use_x(_: impl AsRef<str>) {}
+    fn use_x_again(_: impl AsRef<str>) {}
+}
diff --git a/src/tools/clippy/tests/ui/needless_borrow.stderr b/src/tools/clippy/tests/ui/needless_borrow.stderr
index 5af68706d4ba..8b593268bec2 100644
--- a/src/tools/clippy/tests/ui/needless_borrow.stderr
+++ b/src/tools/clippy/tests/ui/needless_borrow.stderr
@@ -1,5 +1,5 @@
 error: this expression creates a reference which is immediately dereferenced by the compiler
-  --> $DIR/needless_borrow.rs:11:15
+  --> $DIR/needless_borrow.rs:15:15
    |
 LL |     let _ = x(&&a); // warn
    |               ^^^ help: change this to: `&a`
@@ -7,172 +7,208 @@ LL |     let _ = x(&&a); // warn
    = note: `-D clippy::needless-borrow` implied by `-D warnings`
 
 error: this expression creates a reference which is immediately dereferenced by the compiler
-  --> $DIR/needless_borrow.rs:15:13
+  --> $DIR/needless_borrow.rs:19:13
    |
 LL |     mut_ref(&mut &mut b); // warn
    |             ^^^^^^^^^^^ help: change this to: `&mut b`
 
 error: this expression creates a reference which is immediately dereferenced by the compiler
-  --> $DIR/needless_borrow.rs:27:13
+  --> $DIR/needless_borrow.rs:31:13
    |
 LL |             &&a
    |             ^^^ help: change this to: `&a`
 
 error: this expression creates a reference which is immediately dereferenced by the compiler
-  --> $DIR/needless_borrow.rs:29:15
+  --> $DIR/needless_borrow.rs:33:15
    |
 LL |         46 => &&a,
    |               ^^^ help: change this to: `&a`
 
 error: this expression creates a reference which is immediately dereferenced by the compiler
-  --> $DIR/needless_borrow.rs:35:27
+  --> $DIR/needless_borrow.rs:39:27
    |
 LL |                     break &ref_a;
    |                           ^^^^^^ help: change this to: `ref_a`
 
 error: this expression creates a reference which is immediately dereferenced by the compiler
-  --> $DIR/needless_borrow.rs:42:15
+  --> $DIR/needless_borrow.rs:46:15
    |
 LL |     let _ = x(&&&a);
    |               ^^^^ help: change this to: `&a`
 
 error: this expression creates a reference which is immediately dereferenced by the compiler
-  --> $DIR/needless_borrow.rs:43:15
+  --> $DIR/needless_borrow.rs:47:15
    |
 LL |     let _ = x(&mut &&a);
    |               ^^^^^^^^ help: change this to: `&a`
 
 error: this expression creates a reference which is immediately dereferenced by the compiler
-  --> $DIR/needless_borrow.rs:44:15
+  --> $DIR/needless_borrow.rs:48:15
    |
 LL |     let _ = x(&&&mut b);
    |               ^^^^^^^^ help: change this to: `&mut b`
 
 error: this expression creates a reference which is immediately dereferenced by the compiler
-  --> $DIR/needless_borrow.rs:45:15
+  --> $DIR/needless_borrow.rs:49:15
    |
 LL |     let _ = x(&&ref_a);
    |               ^^^^^^^ help: change this to: `ref_a`
 
 error: this expression creates a reference which is immediately dereferenced by the compiler
-  --> $DIR/needless_borrow.rs:48:11
+  --> $DIR/needless_borrow.rs:52:11
    |
 LL |         x(&b);
    |           ^^ help: change this to: `b`
 
 error: this expression creates a reference which is immediately dereferenced by the compiler
-  --> $DIR/needless_borrow.rs:55:13
+  --> $DIR/needless_borrow.rs:59:13
    |
 LL |     mut_ref(&mut x);
    |             ^^^^^^ help: change this to: `x`
 
 error: this expression creates a reference which is immediately dereferenced by the compiler
-  --> $DIR/needless_borrow.rs:56:13
+  --> $DIR/needless_borrow.rs:60:13
    |
 LL |     mut_ref(&mut &mut x);
    |             ^^^^^^^^^^^ help: change this to: `x`
 
 error: this expression creates a reference which is immediately dereferenced by the compiler
-  --> $DIR/needless_borrow.rs:57:23
+  --> $DIR/needless_borrow.rs:61:23
    |
 LL |     let y: &mut i32 = &mut x;
    |                       ^^^^^^ help: change this to: `x`
 
 error: this expression creates a reference which is immediately dereferenced by the compiler
-  --> $DIR/needless_borrow.rs:58:23
+  --> $DIR/needless_borrow.rs:62:23
    |
 LL |     let y: &mut i32 = &mut &mut x;
    |                       ^^^^^^^^^^^ help: change this to: `x`
 
 error: this expression creates a reference which is immediately dereferenced by the compiler
-  --> $DIR/needless_borrow.rs:67:14
+  --> $DIR/needless_borrow.rs:71:14
    |
 LL |         0 => &mut x,
    |              ^^^^^^ help: change this to: `x`
 
 error: this expression creates a reference which is immediately dereferenced by the compiler
-  --> $DIR/needless_borrow.rs:73:14
+  --> $DIR/needless_borrow.rs:77:14
    |
 LL |         0 => &mut x,
    |              ^^^^^^ help: change this to: `x`
 
 error: this expression borrows a value the compiler would automatically borrow
-  --> $DIR/needless_borrow.rs:85:13
+  --> $DIR/needless_borrow.rs:89:13
    |
 LL |     let _ = (&x).0;
    |             ^^^^ help: change this to: `x`
 
 error: this expression borrows a value the compiler would automatically borrow
-  --> $DIR/needless_borrow.rs:87:22
+  --> $DIR/needless_borrow.rs:91:22
    |
 LL |     let _ = unsafe { (&*x).0 };
    |                      ^^^^^ help: change this to: `(*x)`
 
 error: this expression creates a reference which is immediately dereferenced by the compiler
-  --> $DIR/needless_borrow.rs:97:5
+  --> $DIR/needless_borrow.rs:101:5
    |
 LL |     (&&()).foo();
    |     ^^^^^^ help: change this to: `(&())`
 
 error: this expression creates a reference which is immediately dereferenced by the compiler
-  --> $DIR/needless_borrow.rs:106:5
+  --> $DIR/needless_borrow.rs:110:5
    |
 LL |     (&&5).foo();
    |     ^^^^^ help: change this to: `(&5)`
 
 error: the borrowed expression implements the required traits
-  --> $DIR/needless_borrow.rs:131:51
+  --> $DIR/needless_borrow.rs:135:51
    |
 LL |     let _ = std::process::Command::new("ls").args(&["-a", "-l"]).status().unwrap();
    |                                                   ^^^^^^^^^^^^^ help: change this to: `["-a", "-l"]`
 
 error: the borrowed expression implements the required traits
-  --> $DIR/needless_borrow.rs:132:44
+  --> $DIR/needless_borrow.rs:136:44
    |
 LL |     let _ = std::path::Path::new(".").join(&&".");
    |                                            ^^^^^ help: change this to: `"."`
 
 error: the borrowed expression implements the required traits
-  --> $DIR/needless_borrow.rs:133:23
+  --> $DIR/needless_borrow.rs:137:23
    |
 LL |     deref_target_is_x(&X);
    |                       ^^ help: change this to: `X`
 
 error: the borrowed expression implements the required traits
-  --> $DIR/needless_borrow.rs:134:26
+  --> $DIR/needless_borrow.rs:138:26
    |
 LL |     multiple_constraints(&[[""]]);
    |                          ^^^^^^^ help: change this to: `[[""]]`
 
 error: the borrowed expression implements the required traits
-  --> $DIR/needless_borrow.rs:135:45
+  --> $DIR/needless_borrow.rs:139:45
    |
 LL |     multiple_constraints_normalizes_to_same(&X, X);
    |                                             ^^ help: change this to: `X`
 
 error: this expression creates a reference which is immediately dereferenced by the compiler
-  --> $DIR/needless_borrow.rs:136:32
+  --> $DIR/needless_borrow.rs:140:32
    |
 LL |     let _ = Some("").unwrap_or(&"");
    |                                ^^^ help: change this to: `""`
 
+error: the borrowed expression implements the required traits
+  --> $DIR/needless_borrow.rs:141:33
+   |
+LL |     let _ = std::fs::write("x", &"".to_string());
+   |                                 ^^^^^^^^^^^^^^^ help: change this to: `"".to_string()`
+
 error: this expression borrows a value the compiler would automatically borrow
-  --> $DIR/needless_borrow.rs:187:13
+  --> $DIR/needless_borrow.rs:192:13
    |
 LL |             (&self.f)()
    |             ^^^^^^^^^ help: change this to: `(self.f)`
 
 error: this expression borrows a value the compiler would automatically borrow
-  --> $DIR/needless_borrow.rs:196:13
+  --> $DIR/needless_borrow.rs:201:13
    |
 LL |             (&mut self.f)()
    |             ^^^^^^^^^^^^^ help: change this to: `(self.f)`
 
 error: the borrowed expression implements the required traits
-  --> $DIR/needless_borrow.rs:298:55
+  --> $DIR/needless_borrow.rs:286:20
+   |
+LL |         takes_iter(&mut x)
+   |                    ^^^^^^ help: change this to: `x`
+
+error: the borrowed expression implements the required traits
+  --> $DIR/needless_borrow.rs:304:55
    |
 LL |         let _ = std::process::Command::new("ls").args(&["-a", "-l"]).status().unwrap();
    |                                                       ^^^^^^^^^^^^^ help: change this to: `["-a", "-l"]`
 
-error: aborting due to 29 previous errors
+error: the borrowed expression implements the required traits
+  --> $DIR/needless_borrow.rs:344:37
+   |
+LL |         let _ = std::fs::write("x", &arg);
+   |                                     ^^^^ help: change this to: `arg`
+
+error: the borrowed expression implements the required traits
+  --> $DIR/needless_borrow.rs:345:37
+   |
+LL |         let _ = std::fs::write("x", &loc);
+   |                                     ^^^^ help: change this to: `loc`
+
+error: the borrowed expression implements the required traits
+  --> $DIR/needless_borrow.rs:364:15
+   |
+LL |         debug(&x);
+   |               ^^ help: change this to: `x`
+
+error: the borrowed expression implements the required traits
+  --> $DIR/needless_borrow.rs:374:15
+   |
+LL |         use_x(&x);
+   |               ^^ help: change this to: `x`
+
+error: aborting due to 35 previous errors
 
diff --git a/src/tools/clippy/tests/ui/option_as_ref_deref.fixed b/src/tools/clippy/tests/ui/option_as_ref_deref.fixed
index 07d7f0b45b0c..bc376d0d7fb3 100644
--- a/src/tools/clippy/tests/ui/option_as_ref_deref.fixed
+++ b/src/tools/clippy/tests/ui/option_as_ref_deref.fixed
@@ -1,6 +1,7 @@
 // run-rustfix
 
-#![allow(unused_imports, clippy::redundant_clone)]
+#![feature(custom_inner_attributes)]
+#![allow(unused, clippy::redundant_clone)]
 #![warn(clippy::option_as_ref_deref)]
 
 use std::ffi::{CString, OsString};
@@ -42,3 +43,17 @@ fn main() {
     // Issue #5927
     let _ = opt.as_deref();
 }
+
+fn msrv_1_39() {
+    #![clippy::msrv = "1.39"]
+
+    let opt = Some(String::from("123"));
+    let _ = opt.as_ref().map(String::as_str);
+}
+
+fn msrv_1_40() {
+    #![clippy::msrv = "1.40"]
+
+    let opt = Some(String::from("123"));
+    let _ = opt.as_deref();
+}
diff --git a/src/tools/clippy/tests/ui/option_as_ref_deref.rs b/src/tools/clippy/tests/ui/option_as_ref_deref.rs
index 6ae059c9425d..ba3a2eedc225 100644
--- a/src/tools/clippy/tests/ui/option_as_ref_deref.rs
+++ b/src/tools/clippy/tests/ui/option_as_ref_deref.rs
@@ -1,6 +1,7 @@
 // run-rustfix
 
-#![allow(unused_imports, clippy::redundant_clone)]
+#![feature(custom_inner_attributes)]
+#![allow(unused, clippy::redundant_clone)]
 #![warn(clippy::option_as_ref_deref)]
 
 use std::ffi::{CString, OsString};
@@ -45,3 +46,17 @@ fn main() {
     // Issue #5927
     let _ = opt.as_ref().map(std::ops::Deref::deref);
 }
+
+fn msrv_1_39() {
+    #![clippy::msrv = "1.39"]
+
+    let opt = Some(String::from("123"));
+    let _ = opt.as_ref().map(String::as_str);
+}
+
+fn msrv_1_40() {
+    #![clippy::msrv = "1.40"]
+
+    let opt = Some(String::from("123"));
+    let _ = opt.as_ref().map(String::as_str);
+}
diff --git a/src/tools/clippy/tests/ui/option_as_ref_deref.stderr b/src/tools/clippy/tests/ui/option_as_ref_deref.stderr
index 62f282324752..7de8b3b6ba43 100644
--- a/src/tools/clippy/tests/ui/option_as_ref_deref.stderr
+++ b/src/tools/clippy/tests/ui/option_as_ref_deref.stderr
@@ -1,5 +1,5 @@
 error: called `.as_ref().map(Deref::deref)` on an Option value. This can be done more directly by calling `opt.clone().as_deref()` instead
-  --> $DIR/option_as_ref_deref.rs:13:13
+  --> $DIR/option_as_ref_deref.rs:14:13
    |
 LL |     let _ = opt.clone().as_ref().map(Deref::deref).map(str::len);
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try using as_deref instead: `opt.clone().as_deref()`
@@ -7,7 +7,7 @@ LL |     let _ = opt.clone().as_ref().map(Deref::deref).map(str::len);
    = note: `-D clippy::option-as-ref-deref` implied by `-D warnings`
 
 error: called `.as_ref().map(Deref::deref)` on an Option value. This can be done more directly by calling `opt.clone().as_deref()` instead
-  --> $DIR/option_as_ref_deref.rs:16:13
+  --> $DIR/option_as_ref_deref.rs:17:13
    |
 LL |       let _ = opt.clone()
    |  _____________^
@@ -17,94 +17,100 @@ LL | |         )
    | |_________^ help: try using as_deref instead: `opt.clone().as_deref()`
 
 error: called `.as_mut().map(DerefMut::deref_mut)` on an Option value. This can be done more directly by calling `opt.as_deref_mut()` instead
-  --> $DIR/option_as_ref_deref.rs:22:13
+  --> $DIR/option_as_ref_deref.rs:23:13
    |
 LL |     let _ = opt.as_mut().map(DerefMut::deref_mut);
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try using as_deref_mut instead: `opt.as_deref_mut()`
 
 error: called `.as_ref().map(String::as_str)` on an Option value. This can be done more directly by calling `opt.as_deref()` instead
-  --> $DIR/option_as_ref_deref.rs:24:13
+  --> $DIR/option_as_ref_deref.rs:25:13
    |
 LL |     let _ = opt.as_ref().map(String::as_str);
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try using as_deref instead: `opt.as_deref()`
 
 error: called `.as_ref().map(|x| x.as_str())` on an Option value. This can be done more directly by calling `opt.as_deref()` instead
-  --> $DIR/option_as_ref_deref.rs:25:13
+  --> $DIR/option_as_ref_deref.rs:26:13
    |
 LL |     let _ = opt.as_ref().map(|x| x.as_str());
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try using as_deref instead: `opt.as_deref()`
 
 error: called `.as_mut().map(String::as_mut_str)` on an Option value. This can be done more directly by calling `opt.as_deref_mut()` instead
-  --> $DIR/option_as_ref_deref.rs:26:13
+  --> $DIR/option_as_ref_deref.rs:27:13
    |
 LL |     let _ = opt.as_mut().map(String::as_mut_str);
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try using as_deref_mut instead: `opt.as_deref_mut()`
 
 error: called `.as_mut().map(|x| x.as_mut_str())` on an Option value. This can be done more directly by calling `opt.as_deref_mut()` instead
-  --> $DIR/option_as_ref_deref.rs:27:13
+  --> $DIR/option_as_ref_deref.rs:28:13
    |
 LL |     let _ = opt.as_mut().map(|x| x.as_mut_str());
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try using as_deref_mut instead: `opt.as_deref_mut()`
 
 error: called `.as_ref().map(CString::as_c_str)` on an Option value. This can be done more directly by calling `Some(CString::new(vec![]).unwrap()).as_deref()` instead
-  --> $DIR/option_as_ref_deref.rs:28:13
+  --> $DIR/option_as_ref_deref.rs:29:13
    |
 LL |     let _ = Some(CString::new(vec![]).unwrap()).as_ref().map(CString::as_c_str);
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try using as_deref instead: `Some(CString::new(vec![]).unwrap()).as_deref()`
 
 error: called `.as_ref().map(OsString::as_os_str)` on an Option value. This can be done more directly by calling `Some(OsString::new()).as_deref()` instead
-  --> $DIR/option_as_ref_deref.rs:29:13
+  --> $DIR/option_as_ref_deref.rs:30:13
    |
 LL |     let _ = Some(OsString::new()).as_ref().map(OsString::as_os_str);
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try using as_deref instead: `Some(OsString::new()).as_deref()`
 
 error: called `.as_ref().map(PathBuf::as_path)` on an Option value. This can be done more directly by calling `Some(PathBuf::new()).as_deref()` instead
-  --> $DIR/option_as_ref_deref.rs:30:13
+  --> $DIR/option_as_ref_deref.rs:31:13
    |
 LL |     let _ = Some(PathBuf::new()).as_ref().map(PathBuf::as_path);
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try using as_deref instead: `Some(PathBuf::new()).as_deref()`
 
 error: called `.as_ref().map(Vec::as_slice)` on an Option value. This can be done more directly by calling `Some(Vec::<()>::new()).as_deref()` instead
-  --> $DIR/option_as_ref_deref.rs:31:13
+  --> $DIR/option_as_ref_deref.rs:32:13
    |
 LL |     let _ = Some(Vec::<()>::new()).as_ref().map(Vec::as_slice);
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try using as_deref instead: `Some(Vec::<()>::new()).as_deref()`
 
 error: called `.as_mut().map(Vec::as_mut_slice)` on an Option value. This can be done more directly by calling `Some(Vec::<()>::new()).as_deref_mut()` instead
-  --> $DIR/option_as_ref_deref.rs:32:13
+  --> $DIR/option_as_ref_deref.rs:33:13
    |
 LL |     let _ = Some(Vec::<()>::new()).as_mut().map(Vec::as_mut_slice);
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try using as_deref_mut instead: `Some(Vec::<()>::new()).as_deref_mut()`
 
 error: called `.as_ref().map(|x| x.deref())` on an Option value. This can be done more directly by calling `opt.as_deref()` instead
-  --> $DIR/option_as_ref_deref.rs:34:13
+  --> $DIR/option_as_ref_deref.rs:35:13
    |
 LL |     let _ = opt.as_ref().map(|x| x.deref());
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try using as_deref instead: `opt.as_deref()`
 
 error: called `.as_mut().map(|x| x.deref_mut())` on an Option value. This can be done more directly by calling `opt.clone().as_deref_mut()` instead
-  --> $DIR/option_as_ref_deref.rs:35:13
+  --> $DIR/option_as_ref_deref.rs:36:13
    |
 LL |     let _ = opt.clone().as_mut().map(|x| x.deref_mut()).map(|x| x.len());
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try using as_deref_mut instead: `opt.clone().as_deref_mut()`
 
 error: called `.as_ref().map(|x| &**x)` on an Option value. This can be done more directly by calling `opt.as_deref()` instead
-  --> $DIR/option_as_ref_deref.rs:42:13
+  --> $DIR/option_as_ref_deref.rs:43:13
    |
 LL |     let _ = opt.as_ref().map(|x| &**x);
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try using as_deref instead: `opt.as_deref()`
 
 error: called `.as_mut().map(|x| &mut **x)` on an Option value. This can be done more directly by calling `opt.as_deref_mut()` instead
-  --> $DIR/option_as_ref_deref.rs:43:13
+  --> $DIR/option_as_ref_deref.rs:44:13
    |
 LL |     let _ = opt.as_mut().map(|x| &mut **x);
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try using as_deref_mut instead: `opt.as_deref_mut()`
 
 error: called `.as_ref().map(std::ops::Deref::deref)` on an Option value. This can be done more directly by calling `opt.as_deref()` instead
-  --> $DIR/option_as_ref_deref.rs:46:13
+  --> $DIR/option_as_ref_deref.rs:47:13
    |
 LL |     let _ = opt.as_ref().map(std::ops::Deref::deref);
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try using as_deref instead: `opt.as_deref()`
 
-error: aborting due to 17 previous errors
+error: called `.as_ref().map(String::as_str)` on an Option value. This can be done more directly by calling `opt.as_deref()` instead
+  --> $DIR/option_as_ref_deref.rs:61:13
+   |
+LL |     let _ = opt.as_ref().map(String::as_str);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try using as_deref instead: `opt.as_deref()`
+
+error: aborting due to 18 previous errors
 
diff --git a/src/tools/clippy/tests/ui/or_fun_call.fixed b/src/tools/clippy/tests/ui/or_fun_call.fixed
index 896430780ea8..23b1aa8bebd5 100644
--- a/src/tools/clippy/tests/ui/or_fun_call.fixed
+++ b/src/tools/clippy/tests/ui/or_fun_call.fixed
@@ -225,4 +225,15 @@ mod issue8239 {
     }
 }
 
+mod issue9608 {
+    fn sig_drop() {
+        enum X {
+            X(std::fs::File),
+            Y(u32),
+        }
+
+        let _ = None.unwrap_or(X::Y(0));
+    }
+}
+
 fn main() {}
diff --git a/src/tools/clippy/tests/ui/or_fun_call.rs b/src/tools/clippy/tests/ui/or_fun_call.rs
index 2473163d4fd2..039998f22dd7 100644
--- a/src/tools/clippy/tests/ui/or_fun_call.rs
+++ b/src/tools/clippy/tests/ui/or_fun_call.rs
@@ -225,4 +225,15 @@ mod issue8239 {
     }
 }
 
+mod issue9608 {
+    fn sig_drop() {
+        enum X {
+            X(std::fs::File),
+            Y(u32),
+        }
+
+        let _ = None.unwrap_or(X::Y(0));
+    }
+}
+
 fn main() {}
diff --git a/src/tools/clippy/tests/ui/partial_pub_fields.rs b/src/tools/clippy/tests/ui/partial_pub_fields.rs
new file mode 100644
index 000000000000..668545da8441
--- /dev/null
+++ b/src/tools/clippy/tests/ui/partial_pub_fields.rs
@@ -0,0 +1,40 @@
+#![allow(unused)]
+#![warn(clippy::partial_pub_fields)]
+
+fn main() {
+    use std::collections::HashMap;
+
+    #[derive(Default)]
+    pub struct FileSet {
+        files: HashMap<String, u32>,
+        pub paths: HashMap<u32, String>,
+    }
+
+    pub struct Color {
+        pub r: u8,
+        pub g: u8,
+        b: u8,
+    }
+
+    pub struct Point(i32, pub i32);
+
+    pub struct Visibility {
+        r#pub: bool,
+        pub pos: u32,
+    }
+
+    // Don't lint on empty structs;
+    pub struct Empty1;
+    pub struct Empty2();
+    pub struct Empty3 {};
+
+    // Don't lint on structs with one field.
+    pub struct Single1(i32);
+    pub struct Single2(pub i32);
+    pub struct Single3 {
+        v1: i32,
+    }
+    pub struct Single4 {
+        pub v1: i32,
+    }
+}
diff --git a/src/tools/clippy/tests/ui/partial_pub_fields.stderr b/src/tools/clippy/tests/ui/partial_pub_fields.stderr
new file mode 100644
index 000000000000..84cfc1a91940
--- /dev/null
+++ b/src/tools/clippy/tests/ui/partial_pub_fields.stderr
@@ -0,0 +1,35 @@
+error: mixed usage of pub and non-pub fields
+  --> $DIR/partial_pub_fields.rs:10:9
+   |
+LL |         pub paths: HashMap<u32, String>,
+   |         ^^^
+   |
+   = help: consider using private field here
+   = note: `-D clippy::partial-pub-fields` implied by `-D warnings`
+
+error: mixed usage of pub and non-pub fields
+  --> $DIR/partial_pub_fields.rs:16:9
+   |
+LL |         b: u8,
+   |         ^
+   |
+   = help: consider using public field here
+
+error: mixed usage of pub and non-pub fields
+  --> $DIR/partial_pub_fields.rs:19:27
+   |
+LL |     pub struct Point(i32, pub i32);
+   |                           ^^^
+   |
+   = help: consider using private field here
+
+error: mixed usage of pub and non-pub fields
+  --> $DIR/partial_pub_fields.rs:23:9
+   |
+LL |         pub pos: u32,
+   |         ^^^
+   |
+   = help: consider using private field here
+
+error: aborting due to 4 previous errors
+
diff --git a/src/tools/clippy/tests/ui/ptr_arg.rs b/src/tools/clippy/tests/ui/ptr_arg.rs
index fd15001e540c..5f54101ca15a 100644
--- a/src/tools/clippy/tests/ui/ptr_arg.rs
+++ b/src/tools/clippy/tests/ui/ptr_arg.rs
@@ -3,7 +3,7 @@
 #![warn(clippy::ptr_arg)]
 
 use std::borrow::Cow;
-use std::path::PathBuf;
+use std::path::{Path, PathBuf};
 
 fn do_vec(x: &Vec<i64>) {
     //Nothing here
@@ -207,3 +207,31 @@ fn cow_conditional_to_mut(a: &mut Cow<str>) {
         a.to_mut().push_str("foo");
     }
 }
+
+// Issue #9542
+fn dyn_trait_ok(a: &mut Vec<u32>, b: &mut String, c: &mut PathBuf) {
+    trait T {}
+    impl<U> T for Vec<U> {}
+    impl T for String {}
+    impl T for PathBuf {}
+    fn takes_dyn(_: &mut dyn T) {}
+
+    takes_dyn(a);
+    takes_dyn(b);
+    takes_dyn(c);
+}
+
+fn dyn_trait(a: &mut Vec<u32>, b: &mut String, c: &mut PathBuf) {
+    trait T {}
+    impl<U> T for Vec<U> {}
+    impl<U> T for [U] {}
+    impl T for String {}
+    impl T for str {}
+    impl T for PathBuf {}
+    impl T for Path {}
+    fn takes_dyn(_: &mut dyn T) {}
+
+    takes_dyn(a);
+    takes_dyn(b);
+    takes_dyn(c);
+}
diff --git a/src/tools/clippy/tests/ui/ptr_arg.stderr b/src/tools/clippy/tests/ui/ptr_arg.stderr
index d64b5f454a5a..6b4de98ce88c 100644
--- a/src/tools/clippy/tests/ui/ptr_arg.stderr
+++ b/src/tools/clippy/tests/ui/ptr_arg.stderr
@@ -162,5 +162,23 @@ error: writing `&mut Vec` instead of `&mut [_]` involves a new object where a sl
 LL | fn mut_vec_slice_methods(v: &mut Vec<u32>) {
    |                             ^^^^^^^^^^^^^ help: change this to: `&mut [u32]`
 
-error: aborting due to 17 previous errors
+error: writing `&mut Vec` instead of `&mut [_]` involves a new object where a slice will do
+  --> $DIR/ptr_arg.rs:224:17
+   |
+LL | fn dyn_trait(a: &mut Vec<u32>, b: &mut String, c: &mut PathBuf) {
+   |                 ^^^^^^^^^^^^^ help: change this to: `&mut [u32]`
+
+error: writing `&mut String` instead of `&mut str` involves a new object where a slice will do
+  --> $DIR/ptr_arg.rs:224:35
+   |
+LL | fn dyn_trait(a: &mut Vec<u32>, b: &mut String, c: &mut PathBuf) {
+   |                                   ^^^^^^^^^^^ help: change this to: `&mut str`
+
+error: writing `&mut PathBuf` instead of `&mut Path` involves a new object where a slice will do
+  --> $DIR/ptr_arg.rs:224:51
+   |
+LL | fn dyn_trait(a: &mut Vec<u32>, b: &mut String, c: &mut PathBuf) {
+   |                                                   ^^^^^^^^^^^^ help: change this to: `&mut Path`
+
+error: aborting due to 20 previous errors
 
diff --git a/src/tools/clippy/tests/ui/range_contains.fixed b/src/tools/clippy/tests/ui/range_contains.fixed
index 85d021b2f25e..824f00cb99e8 100644
--- a/src/tools/clippy/tests/ui/range_contains.fixed
+++ b/src/tools/clippy/tests/ui/range_contains.fixed
@@ -1,10 +1,12 @@
 // run-rustfix
 
-#[warn(clippy::manual_range_contains)]
-#[allow(unused)]
-#[allow(clippy::no_effect)]
-#[allow(clippy::short_circuit_statement)]
-#[allow(clippy::unnecessary_operation)]
+#![feature(custom_inner_attributes)]
+#![warn(clippy::manual_range_contains)]
+#![allow(unused)]
+#![allow(clippy::no_effect)]
+#![allow(clippy::short_circuit_statement)]
+#![allow(clippy::unnecessary_operation)]
+
 fn main() {
     let x = 9_i32;
 
@@ -62,3 +64,17 @@ fn main() {
 pub const fn in_range(a: i32) -> bool {
     3 <= a && a <= 20
 }
+
+fn msrv_1_34() {
+    #![clippy::msrv = "1.34"]
+
+    let x = 5;
+    x >= 8 && x < 34;
+}
+
+fn msrv_1_35() {
+    #![clippy::msrv = "1.35"]
+
+    let x = 5;
+    (8..35).contains(&x);
+}
diff --git a/src/tools/clippy/tests/ui/range_contains.rs b/src/tools/clippy/tests/ui/range_contains.rs
index 9a7a75dc1325..df925eeadfe5 100644
--- a/src/tools/clippy/tests/ui/range_contains.rs
+++ b/src/tools/clippy/tests/ui/range_contains.rs
@@ -1,10 +1,12 @@
 // run-rustfix
 
-#[warn(clippy::manual_range_contains)]
-#[allow(unused)]
-#[allow(clippy::no_effect)]
-#[allow(clippy::short_circuit_statement)]
-#[allow(clippy::unnecessary_operation)]
+#![feature(custom_inner_attributes)]
+#![warn(clippy::manual_range_contains)]
+#![allow(unused)]
+#![allow(clippy::no_effect)]
+#![allow(clippy::short_circuit_statement)]
+#![allow(clippy::unnecessary_operation)]
+
 fn main() {
     let x = 9_i32;
 
@@ -62,3 +64,17 @@ fn main() {
 pub const fn in_range(a: i32) -> bool {
     3 <= a && a <= 20
 }
+
+fn msrv_1_34() {
+    #![clippy::msrv = "1.34"]
+
+    let x = 5;
+    x >= 8 && x < 34;
+}
+
+fn msrv_1_35() {
+    #![clippy::msrv = "1.35"]
+
+    let x = 5;
+    x >= 8 && x < 35;
+}
diff --git a/src/tools/clippy/tests/ui/range_contains.stderr b/src/tools/clippy/tests/ui/range_contains.stderr
index 936859db5a12..9689e665b05c 100644
--- a/src/tools/clippy/tests/ui/range_contains.stderr
+++ b/src/tools/clippy/tests/ui/range_contains.stderr
@@ -1,5 +1,5 @@
 error: manual `Range::contains` implementation
-  --> $DIR/range_contains.rs:12:5
+  --> $DIR/range_contains.rs:14:5
    |
 LL |     x >= 8 && x < 12;
    |     ^^^^^^^^^^^^^^^^ help: use: `(8..12).contains(&x)`
@@ -7,118 +7,124 @@ LL |     x >= 8 && x < 12;
    = note: `-D clippy::manual-range-contains` implied by `-D warnings`
 
 error: manual `Range::contains` implementation
-  --> $DIR/range_contains.rs:13:5
+  --> $DIR/range_contains.rs:15:5
    |
 LL |     x < 42 && x >= 21;
    |     ^^^^^^^^^^^^^^^^^ help: use: `(21..42).contains(&x)`
 
 error: manual `Range::contains` implementation
-  --> $DIR/range_contains.rs:14:5
+  --> $DIR/range_contains.rs:16:5
    |
 LL |     100 > x && 1 <= x;
    |     ^^^^^^^^^^^^^^^^^ help: use: `(1..100).contains(&x)`
 
 error: manual `RangeInclusive::contains` implementation
-  --> $DIR/range_contains.rs:17:5
+  --> $DIR/range_contains.rs:19:5
    |
 LL |     x >= 9 && x <= 99;
    |     ^^^^^^^^^^^^^^^^^ help: use: `(9..=99).contains(&x)`
 
 error: manual `RangeInclusive::contains` implementation
-  --> $DIR/range_contains.rs:18:5
+  --> $DIR/range_contains.rs:20:5
    |
 LL |     x <= 33 && x >= 1;
    |     ^^^^^^^^^^^^^^^^^ help: use: `(1..=33).contains(&x)`
 
 error: manual `RangeInclusive::contains` implementation
-  --> $DIR/range_contains.rs:19:5
+  --> $DIR/range_contains.rs:21:5
    |
 LL |     999 >= x && 1 <= x;
    |     ^^^^^^^^^^^^^^^^^^ help: use: `(1..=999).contains(&x)`
 
 error: manual `!Range::contains` implementation
-  --> $DIR/range_contains.rs:22:5
+  --> $DIR/range_contains.rs:24:5
    |
 LL |     x < 8 || x >= 12;
    |     ^^^^^^^^^^^^^^^^ help: use: `!(8..12).contains(&x)`
 
 error: manual `!Range::contains` implementation
-  --> $DIR/range_contains.rs:23:5
+  --> $DIR/range_contains.rs:25:5
    |
 LL |     x >= 42 || x < 21;
    |     ^^^^^^^^^^^^^^^^^ help: use: `!(21..42).contains(&x)`
 
 error: manual `!Range::contains` implementation
-  --> $DIR/range_contains.rs:24:5
+  --> $DIR/range_contains.rs:26:5
    |
 LL |     100 <= x || 1 > x;
    |     ^^^^^^^^^^^^^^^^^ help: use: `!(1..100).contains(&x)`
 
 error: manual `!RangeInclusive::contains` implementation
-  --> $DIR/range_contains.rs:27:5
+  --> $DIR/range_contains.rs:29:5
    |
 LL |     x < 9 || x > 99;
    |     ^^^^^^^^^^^^^^^ help: use: `!(9..=99).contains(&x)`
 
 error: manual `!RangeInclusive::contains` implementation
-  --> $DIR/range_contains.rs:28:5
+  --> $DIR/range_contains.rs:30:5
    |
 LL |     x > 33 || x < 1;
    |     ^^^^^^^^^^^^^^^ help: use: `!(1..=33).contains(&x)`
 
 error: manual `!RangeInclusive::contains` implementation
-  --> $DIR/range_contains.rs:29:5
+  --> $DIR/range_contains.rs:31:5
    |
 LL |     999 < x || 1 > x;
    |     ^^^^^^^^^^^^^^^^ help: use: `!(1..=999).contains(&x)`
 
 error: manual `Range::contains` implementation
-  --> $DIR/range_contains.rs:44:5
+  --> $DIR/range_contains.rs:46:5
    |
 LL |     y >= 0. && y < 1.;
    |     ^^^^^^^^^^^^^^^^^ help: use: `(0. ..1.).contains(&y)`
 
 error: manual `!RangeInclusive::contains` implementation
-  --> $DIR/range_contains.rs:45:5
+  --> $DIR/range_contains.rs:47:5
    |
 LL |     y < 0. || y > 1.;
    |     ^^^^^^^^^^^^^^^^ help: use: `!(0. ..=1.).contains(&y)`
 
 error: manual `RangeInclusive::contains` implementation
-  --> $DIR/range_contains.rs:48:5
+  --> $DIR/range_contains.rs:50:5
    |
 LL |     x >= -10 && x <= 10;
    |     ^^^^^^^^^^^^^^^^^^^ help: use: `(-10..=10).contains(&x)`
 
 error: manual `RangeInclusive::contains` implementation
-  --> $DIR/range_contains.rs:50:5
+  --> $DIR/range_contains.rs:52:5
    |
 LL |     y >= -3. && y <= 3.;
    |     ^^^^^^^^^^^^^^^^^^^ help: use: `(-3. ..=3.).contains(&y)`
 
 error: manual `RangeInclusive::contains` implementation
-  --> $DIR/range_contains.rs:55:30
+  --> $DIR/range_contains.rs:57:30
    |
 LL |     (x >= 0) && (x <= 10) && (z >= 0) && (z <= 10);
    |                              ^^^^^^^^^^^^^^^^^^^^^ help: use: `(0..=10).contains(&z)`
 
 error: manual `RangeInclusive::contains` implementation
-  --> $DIR/range_contains.rs:55:5
+  --> $DIR/range_contains.rs:57:5
    |
 LL |     (x >= 0) && (x <= 10) && (z >= 0) && (z <= 10);
    |     ^^^^^^^^^^^^^^^^^^^^^ help: use: `(0..=10).contains(&x)`
 
 error: manual `!Range::contains` implementation
-  --> $DIR/range_contains.rs:56:29
+  --> $DIR/range_contains.rs:58:29
    |
 LL |     (x < 0) || (x >= 10) || (z < 0) || (z >= 10);
    |                             ^^^^^^^^^^^^^^^^^^^^ help: use: `!(0..10).contains(&z)`
 
 error: manual `!Range::contains` implementation
-  --> $DIR/range_contains.rs:56:5
+  --> $DIR/range_contains.rs:58:5
    |
 LL |     (x < 0) || (x >= 10) || (z < 0) || (z >= 10);
    |     ^^^^^^^^^^^^^^^^^^^^ help: use: `!(0..10).contains(&x)`
 
-error: aborting due to 20 previous errors
+error: manual `Range::contains` implementation
+  --> $DIR/range_contains.rs:79:5
+   |
+LL |     x >= 8 && x < 35;
+   |     ^^^^^^^^^^^^^^^^ help: use: `(8..35).contains(&x)`
+
+error: aborting due to 21 previous errors
 
diff --git a/src/tools/clippy/tests/ui/redundant_field_names.fixed b/src/tools/clippy/tests/ui/redundant_field_names.fixed
index 5b4b8eeedd46..34ab552cb1d8 100644
--- a/src/tools/clippy/tests/ui/redundant_field_names.fixed
+++ b/src/tools/clippy/tests/ui/redundant_field_names.fixed
@@ -1,4 +1,6 @@
 // run-rustfix
+
+#![feature(custom_inner_attributes)]
 #![warn(clippy::redundant_field_names)]
 #![allow(clippy::no_effect, dead_code, unused_variables)]
 
@@ -69,3 +71,17 @@ fn issue_3476() {
 
     S { foo: foo::<i32> };
 }
+
+fn msrv_1_16() {
+    #![clippy::msrv = "1.16"]
+
+    let start = 0;
+    let _ = RangeFrom { start: start };
+}
+
+fn msrv_1_17() {
+    #![clippy::msrv = "1.17"]
+
+    let start = 0;
+    let _ = RangeFrom { start };
+}
diff --git a/src/tools/clippy/tests/ui/redundant_field_names.rs b/src/tools/clippy/tests/ui/redundant_field_names.rs
index 3f97b80c5682..a051b1f96f0f 100644
--- a/src/tools/clippy/tests/ui/redundant_field_names.rs
+++ b/src/tools/clippy/tests/ui/redundant_field_names.rs
@@ -1,4 +1,6 @@
 // run-rustfix
+
+#![feature(custom_inner_attributes)]
 #![warn(clippy::redundant_field_names)]
 #![allow(clippy::no_effect, dead_code, unused_variables)]
 
@@ -69,3 +71,17 @@ fn issue_3476() {
 
     S { foo: foo::<i32> };
 }
+
+fn msrv_1_16() {
+    #![clippy::msrv = "1.16"]
+
+    let start = 0;
+    let _ = RangeFrom { start: start };
+}
+
+fn msrv_1_17() {
+    #![clippy::msrv = "1.17"]
+
+    let start = 0;
+    let _ = RangeFrom { start: start };
+}
diff --git a/src/tools/clippy/tests/ui/redundant_field_names.stderr b/src/tools/clippy/tests/ui/redundant_field_names.stderr
index 7976292df224..8b82e062b93a 100644
--- a/src/tools/clippy/tests/ui/redundant_field_names.stderr
+++ b/src/tools/clippy/tests/ui/redundant_field_names.stderr
@@ -1,5 +1,5 @@
 error: redundant field names in struct initialization
-  --> $DIR/redundant_field_names.rs:34:9
+  --> $DIR/redundant_field_names.rs:36:9
    |
 LL |         gender: gender,
    |         ^^^^^^^^^^^^^^ help: replace it with: `gender`
@@ -7,40 +7,46 @@ LL |         gender: gender,
    = note: `-D clippy::redundant-field-names` implied by `-D warnings`
 
 error: redundant field names in struct initialization
-  --> $DIR/redundant_field_names.rs:35:9
+  --> $DIR/redundant_field_names.rs:37:9
    |
 LL |         age: age,
    |         ^^^^^^^^ help: replace it with: `age`
 
 error: redundant field names in struct initialization
-  --> $DIR/redundant_field_names.rs:56:25
+  --> $DIR/redundant_field_names.rs:58:25
    |
 LL |     let _ = RangeFrom { start: start };
    |                         ^^^^^^^^^^^^ help: replace it with: `start`
 
 error: redundant field names in struct initialization
-  --> $DIR/redundant_field_names.rs:57:23
+  --> $DIR/redundant_field_names.rs:59:23
    |
 LL |     let _ = RangeTo { end: end };
    |                       ^^^^^^^^ help: replace it with: `end`
 
 error: redundant field names in struct initialization
-  --> $DIR/redundant_field_names.rs:58:21
+  --> $DIR/redundant_field_names.rs:60:21
    |
 LL |     let _ = Range { start: start, end: end };
    |                     ^^^^^^^^^^^^ help: replace it with: `start`
 
 error: redundant field names in struct initialization
-  --> $DIR/redundant_field_names.rs:58:35
+  --> $DIR/redundant_field_names.rs:60:35
    |
 LL |     let _ = Range { start: start, end: end };
    |                                   ^^^^^^^^ help: replace it with: `end`
 
 error: redundant field names in struct initialization
-  --> $DIR/redundant_field_names.rs:60:32
+  --> $DIR/redundant_field_names.rs:62:32
    |
 LL |     let _ = RangeToInclusive { end: end };
    |                                ^^^^^^^^ help: replace it with: `end`
 
-error: aborting due to 7 previous errors
+error: redundant field names in struct initialization
+  --> $DIR/redundant_field_names.rs:86:25
+   |
+LL |     let _ = RangeFrom { start: start };
+   |                         ^^^^^^^^^^^^ help: replace it with: `start`
+
+error: aborting due to 8 previous errors
 
diff --git a/src/tools/clippy/tests/ui/redundant_static_lifetimes.fixed b/src/tools/clippy/tests/ui/redundant_static_lifetimes.fixed
index acc8f1e25b6e..42110dbe81e8 100644
--- a/src/tools/clippy/tests/ui/redundant_static_lifetimes.fixed
+++ b/src/tools/clippy/tests/ui/redundant_static_lifetimes.fixed
@@ -1,5 +1,6 @@
 // run-rustfix
 
+#![feature(custom_inner_attributes)]
 #![allow(unused)]
 
 #[derive(Debug)]
@@ -54,3 +55,15 @@ impl Foo {
 impl Bar for Foo {
     const TRAIT_VAR: &'static str = "foo";
 }
+
+fn msrv_1_16() {
+    #![clippy::msrv = "1.16"]
+
+    static V: &'static u8 = &16;
+}
+
+fn msrv_1_17() {
+    #![clippy::msrv = "1.17"]
+
+    static V: &u8 = &17;
+}
diff --git a/src/tools/clippy/tests/ui/redundant_static_lifetimes.rs b/src/tools/clippy/tests/ui/redundant_static_lifetimes.rs
index f2f0f78659c9..bc5200bc8625 100644
--- a/src/tools/clippy/tests/ui/redundant_static_lifetimes.rs
+++ b/src/tools/clippy/tests/ui/redundant_static_lifetimes.rs
@@ -1,5 +1,6 @@
 // run-rustfix
 
+#![feature(custom_inner_attributes)]
 #![allow(unused)]
 
 #[derive(Debug)]
@@ -54,3 +55,15 @@ impl Foo {
 impl Bar for Foo {
     const TRAIT_VAR: &'static str = "foo";
 }
+
+fn msrv_1_16() {
+    #![clippy::msrv = "1.16"]
+
+    static V: &'static u8 = &16;
+}
+
+fn msrv_1_17() {
+    #![clippy::msrv = "1.17"]
+
+    static V: &'static u8 = &17;
+}
diff --git a/src/tools/clippy/tests/ui/redundant_static_lifetimes.stderr b/src/tools/clippy/tests/ui/redundant_static_lifetimes.stderr
index 649831f9c069..735113460d28 100644
--- a/src/tools/clippy/tests/ui/redundant_static_lifetimes.stderr
+++ b/src/tools/clippy/tests/ui/redundant_static_lifetimes.stderr
@@ -1,5 +1,5 @@
 error: constants have by default a `'static` lifetime
-  --> $DIR/redundant_static_lifetimes.rs:8:17
+  --> $DIR/redundant_static_lifetimes.rs:9:17
    |
 LL | const VAR_ONE: &'static str = "Test constant #1"; // ERROR Consider removing 'static.
    |                -^^^^^^^---- help: consider removing `'static`: `&str`
@@ -7,94 +7,100 @@ LL | const VAR_ONE: &'static str = "Test constant #1"; // ERROR Consider removin
    = note: `-D clippy::redundant-static-lifetimes` implied by `-D warnings`
 
 error: constants have by default a `'static` lifetime
-  --> $DIR/redundant_static_lifetimes.rs:12:21
+  --> $DIR/redundant_static_lifetimes.rs:13:21
    |
 LL | const VAR_THREE: &[&'static str] = &["one", "two"]; // ERROR Consider removing 'static
    |                    -^^^^^^^---- help: consider removing `'static`: `&str`
 
 error: constants have by default a `'static` lifetime
-  --> $DIR/redundant_static_lifetimes.rs:14:32
+  --> $DIR/redundant_static_lifetimes.rs:15:32
    |
 LL | const VAR_FOUR: (&str, (&str, &'static str), &'static str) = ("on", ("th", "th"), "on"); // ERROR Consider removing 'static
    |                               -^^^^^^^---- help: consider removing `'static`: `&str`
 
 error: constants have by default a `'static` lifetime
-  --> $DIR/redundant_static_lifetimes.rs:14:47
+  --> $DIR/redundant_static_lifetimes.rs:15:47
    |
 LL | const VAR_FOUR: (&str, (&str, &'static str), &'static str) = ("on", ("th", "th"), "on"); // ERROR Consider removing 'static
    |                                              -^^^^^^^---- help: consider removing `'static`: `&str`
 
 error: constants have by default a `'static` lifetime
-  --> $DIR/redundant_static_lifetimes.rs:16:17
+  --> $DIR/redundant_static_lifetimes.rs:17:17
    |
 LL | const VAR_SIX: &'static u8 = &5;
    |                -^^^^^^^--- help: consider removing `'static`: `&u8`
 
 error: constants have by default a `'static` lifetime
-  --> $DIR/redundant_static_lifetimes.rs:18:20
+  --> $DIR/redundant_static_lifetimes.rs:19:20
    |
 LL | const VAR_HEIGHT: &'static Foo = &Foo {};
    |                   -^^^^^^^---- help: consider removing `'static`: `&Foo`
 
 error: constants have by default a `'static` lifetime
-  --> $DIR/redundant_static_lifetimes.rs:20:19
+  --> $DIR/redundant_static_lifetimes.rs:21:19
    |
 LL | const VAR_SLICE: &'static [u8] = b"Test constant #1"; // ERROR Consider removing 'static.
    |                  -^^^^^^^----- help: consider removing `'static`: `&[u8]`
 
 error: constants have by default a `'static` lifetime
-  --> $DIR/redundant_static_lifetimes.rs:22:19
+  --> $DIR/redundant_static_lifetimes.rs:23:19
    |
 LL | const VAR_TUPLE: &'static (u8, u8) = &(1, 2); // ERROR Consider removing 'static.
    |                  -^^^^^^^--------- help: consider removing `'static`: `&(u8, u8)`
 
 error: constants have by default a `'static` lifetime
-  --> $DIR/redundant_static_lifetimes.rs:24:19
+  --> $DIR/redundant_static_lifetimes.rs:25:19
    |
 LL | const VAR_ARRAY: &'static [u8; 1] = b"T"; // ERROR Consider removing 'static.
    |                  -^^^^^^^-------- help: consider removing `'static`: `&[u8; 1]`
 
 error: statics have by default a `'static` lifetime
-  --> $DIR/redundant_static_lifetimes.rs:26:25
+  --> $DIR/redundant_static_lifetimes.rs:27:25
    |
 LL | static STATIC_VAR_ONE: &'static str = "Test static #1"; // ERROR Consider removing 'static.
    |                        -^^^^^^^---- help: consider removing `'static`: `&str`
 
 error: statics have by default a `'static` lifetime
-  --> $DIR/redundant_static_lifetimes.rs:30:29
+  --> $DIR/redundant_static_lifetimes.rs:31:29
    |
 LL | static STATIC_VAR_THREE: &[&'static str] = &["one", "two"]; // ERROR Consider removing 'static
    |                            -^^^^^^^---- help: consider removing `'static`: `&str`
 
 error: statics have by default a `'static` lifetime
-  --> $DIR/redundant_static_lifetimes.rs:32:25
+  --> $DIR/redundant_static_lifetimes.rs:33:25
    |
 LL | static STATIC_VAR_SIX: &'static u8 = &5;
    |                        -^^^^^^^--- help: consider removing `'static`: `&u8`
 
 error: statics have by default a `'static` lifetime
-  --> $DIR/redundant_static_lifetimes.rs:34:28
+  --> $DIR/redundant_static_lifetimes.rs:35:28
    |
 LL | static STATIC_VAR_HEIGHT: &'static Foo = &Foo {};
    |                           -^^^^^^^---- help: consider removing `'static`: `&Foo`
 
 error: statics have by default a `'static` lifetime
-  --> $DIR/redundant_static_lifetimes.rs:36:27
+  --> $DIR/redundant_static_lifetimes.rs:37:27
    |
 LL | static STATIC_VAR_SLICE: &'static [u8] = b"Test static #3"; // ERROR Consider removing 'static.
    |                          -^^^^^^^----- help: consider removing `'static`: `&[u8]`
 
 error: statics have by default a `'static` lifetime
-  --> $DIR/redundant_static_lifetimes.rs:38:27
+  --> $DIR/redundant_static_lifetimes.rs:39:27
    |
 LL | static STATIC_VAR_TUPLE: &'static (u8, u8) = &(1, 2); // ERROR Consider removing 'static.
    |                          -^^^^^^^--------- help: consider removing `'static`: `&(u8, u8)`
 
 error: statics have by default a `'static` lifetime
-  --> $DIR/redundant_static_lifetimes.rs:40:27
+  --> $DIR/redundant_static_lifetimes.rs:41:27
    |
 LL | static STATIC_VAR_ARRAY: &'static [u8; 1] = b"T"; // ERROR Consider removing 'static.
    |                          -^^^^^^^-------- help: consider removing `'static`: `&[u8; 1]`
 
-error: aborting due to 16 previous errors
+error: statics have by default a `'static` lifetime
+  --> $DIR/redundant_static_lifetimes.rs:68:16
+   |
+LL |     static V: &'static u8 = &17;
+   |               -^^^^^^^--- help: consider removing `'static`: `&u8`
+
+error: aborting due to 17 previous errors
 
diff --git a/src/tools/clippy/tests/ui/ref_option_ref.rs b/src/tools/clippy/tests/ui/ref_option_ref.rs
index 2df45c927d71..e487799e1522 100644
--- a/src/tools/clippy/tests/ui/ref_option_ref.rs
+++ b/src/tools/clippy/tests/ui/ref_option_ref.rs
@@ -45,3 +45,8 @@ impl RefOptTrait for u32 {
 fn main() {
     let x: &Option<&u32> = &None;
 }
+
+fn issue9682(arg: &Option<&mut String>) {
+    // Should not lint, as the inner ref is mutable making it non `Copy`
+    println!("{arg:?}");
+}
diff --git a/src/tools/clippy/tests/ui/track-diagnostics.rs b/src/tools/clippy/tests/ui/track-diagnostics.rs
new file mode 100644
index 000000000000..fa9221ed02d7
--- /dev/null
+++ b/src/tools/clippy/tests/ui/track-diagnostics.rs
@@ -0,0 +1,12 @@
+// compile-flags: -Z track-diagnostics
+// error-pattern: created at
+
+// Normalize the emitted location so this doesn't need
+// updating everytime someone adds or removes a line.
+// normalize-stderr-test ".rs:\d+:\d+" -> ".rs:LL:CC"
+
+struct A;
+struct B;
+const S: A = B;
+
+fn main() {}
diff --git a/src/tools/clippy/tests/ui/track-diagnostics.stderr b/src/tools/clippy/tests/ui/track-diagnostics.stderr
new file mode 100644
index 000000000000..ec3031862531
--- /dev/null
+++ b/src/tools/clippy/tests/ui/track-diagnostics.stderr
@@ -0,0 +1,10 @@
+error[E0308]: mismatched types
+  --> $DIR/track-diagnostics.rs:LL:CC
+   |
+LL | const S: A = B;
+   |              ^ expected struct `A`, found struct `B`
+-Ztrack-diagnostics: created at compiler/rustc_infer/src/infer/error_reporting/mod.rs:LL:CC
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/src/tools/clippy/tests/ui/uninlined_format_args.fixed b/src/tools/clippy/tests/ui/uninlined_format_args.fixed
index 3ca7a4019025..106274479751 100644
--- a/src/tools/clippy/tests/ui/uninlined_format_args.fixed
+++ b/src/tools/clippy/tests/ui/uninlined_format_args.fixed
@@ -150,6 +150,19 @@ fn tester(fn_arg: i32) {
 
     println!(with_span!("{0} {1}" "{1} {0}"), local_i32, local_f64);
     println!("{}", with_span!(span val));
+
+    if local_i32 > 0 {
+        panic!("p1 {local_i32}");
+    }
+    if local_i32 > 0 {
+        panic!("p2 {local_i32}");
+    }
+    if local_i32 > 0 {
+        panic!("p3 {local_i32}");
+    }
+    if local_i32 > 0 {
+        panic!("p4 {local_i32}");
+    }
 }
 
 fn main() {
diff --git a/src/tools/clippy/tests/ui/uninlined_format_args.rs b/src/tools/clippy/tests/ui/uninlined_format_args.rs
index 924191f4324c..8e495ebd083a 100644
--- a/src/tools/clippy/tests/ui/uninlined_format_args.rs
+++ b/src/tools/clippy/tests/ui/uninlined_format_args.rs
@@ -150,6 +150,19 @@ fn tester(fn_arg: i32) {
 
     println!(with_span!("{0} {1}" "{1} {0}"), local_i32, local_f64);
     println!("{}", with_span!(span val));
+
+    if local_i32 > 0 {
+        panic!("p1 {}", local_i32);
+    }
+    if local_i32 > 0 {
+        panic!("p2 {0}", local_i32);
+    }
+    if local_i32 > 0 {
+        panic!("p3 {local_i32}", local_i32 = local_i32);
+    }
+    if local_i32 > 0 {
+        panic!("p4 {local_i32}");
+    }
 }
 
 fn main() {
diff --git a/src/tools/clippy/tests/ui/uninlined_format_args.stderr b/src/tools/clippy/tests/ui/uninlined_format_args.stderr
index d1a774926342..2ce3b7fa960c 100644
--- a/src/tools/clippy/tests/ui/uninlined_format_args.stderr
+++ b/src/tools/clippy/tests/ui/uninlined_format_args.stderr
@@ -828,7 +828,43 @@ LL +     println!("{val}");
    |
 
 error: variables can be used directly in the `format!` string
-  --> $DIR/uninlined_format_args.rs:168:5
+  --> $DIR/uninlined_format_args.rs:155:9
+   |
+LL |         panic!("p1 {}", local_i32);
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: change this to
+   |
+LL -         panic!("p1 {}", local_i32);
+LL +         panic!("p1 {local_i32}");
+   |
+
+error: variables can be used directly in the `format!` string
+  --> $DIR/uninlined_format_args.rs:158:9
+   |
+LL |         panic!("p2 {0}", local_i32);
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: change this to
+   |
+LL -         panic!("p2 {0}", local_i32);
+LL +         panic!("p2 {local_i32}");
+   |
+
+error: variables can be used directly in the `format!` string
+  --> $DIR/uninlined_format_args.rs:161:9
+   |
+LL |         panic!("p3 {local_i32}", local_i32 = local_i32);
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: change this to
+   |
+LL -         panic!("p3 {local_i32}", local_i32 = local_i32);
+LL +         panic!("p3 {local_i32}");
+   |
+
+error: variables can be used directly in the `format!` string
+  --> $DIR/uninlined_format_args.rs:181:5
    |
 LL |     println!("expand='{}'", local_i32);
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -839,5 +875,5 @@ LL -     println!("expand='{}'", local_i32);
 LL +     println!("expand='{local_i32}'");
    |
 
-error: aborting due to 70 previous errors
+error: aborting due to 73 previous errors
 
diff --git a/src/tools/clippy/tests/ui/uninlined_format_args_panic.edition2018.fixed b/src/tools/clippy/tests/ui/uninlined_format_args_panic.edition2018.fixed
new file mode 100644
index 000000000000..96cc0877960e
--- /dev/null
+++ b/src/tools/clippy/tests/ui/uninlined_format_args_panic.edition2018.fixed
@@ -0,0 +1,29 @@
+// revisions: edition2018 edition2021
+//[edition2018] edition:2018
+//[edition2021] edition:2021
+// run-rustfix
+
+#![warn(clippy::uninlined_format_args)]
+
+fn main() {
+    let var = 1;
+
+    println!("val='{var}'");
+
+    if var > 0 {
+        panic!("p1 {}", var);
+    }
+    if var > 0 {
+        panic!("p2 {0}", var);
+    }
+    if var > 0 {
+        panic!("p3 {var}", var = var);
+    }
+
+    #[allow(non_fmt_panics)]
+    {
+        if var > 0 {
+            panic!("p4 {var}");
+        }
+    }
+}
diff --git a/src/tools/clippy/tests/ui/uninlined_format_args_panic.edition2018.stderr b/src/tools/clippy/tests/ui/uninlined_format_args_panic.edition2018.stderr
new file mode 100644
index 000000000000..2c8061259229
--- /dev/null
+++ b/src/tools/clippy/tests/ui/uninlined_format_args_panic.edition2018.stderr
@@ -0,0 +1,15 @@
+error: variables can be used directly in the `format!` string
+  --> $DIR/uninlined_format_args_panic.rs:11:5
+   |
+LL |     println!("val='{}'", var);
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: `-D clippy::uninlined-format-args` implied by `-D warnings`
+help: change this to
+   |
+LL -     println!("val='{}'", var);
+LL +     println!("val='{var}'");
+   |
+
+error: aborting due to previous error
+
diff --git a/src/tools/clippy/tests/ui/uninlined_format_args_panic.edition2021.fixed b/src/tools/clippy/tests/ui/uninlined_format_args_panic.edition2021.fixed
new file mode 100644
index 000000000000..faf8ca4d3a79
--- /dev/null
+++ b/src/tools/clippy/tests/ui/uninlined_format_args_panic.edition2021.fixed
@@ -0,0 +1,29 @@
+// revisions: edition2018 edition2021
+//[edition2018] edition:2018
+//[edition2021] edition:2021
+// run-rustfix
+
+#![warn(clippy::uninlined_format_args)]
+
+fn main() {
+    let var = 1;
+
+    println!("val='{var}'");
+
+    if var > 0 {
+        panic!("p1 {var}");
+    }
+    if var > 0 {
+        panic!("p2 {var}");
+    }
+    if var > 0 {
+        panic!("p3 {var}");
+    }
+
+    #[allow(non_fmt_panics)]
+    {
+        if var > 0 {
+            panic!("p4 {var}");
+        }
+    }
+}
diff --git a/src/tools/clippy/tests/ui/uninlined_format_args_panic.edition2021.stderr b/src/tools/clippy/tests/ui/uninlined_format_args_panic.edition2021.stderr
new file mode 100644
index 000000000000..0f09c45f4132
--- /dev/null
+++ b/src/tools/clippy/tests/ui/uninlined_format_args_panic.edition2021.stderr
@@ -0,0 +1,51 @@
+error: variables can be used directly in the `format!` string
+  --> $DIR/uninlined_format_args_panic.rs:11:5
+   |
+LL |     println!("val='{}'", var);
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: `-D clippy::uninlined-format-args` implied by `-D warnings`
+help: change this to
+   |
+LL -     println!("val='{}'", var);
+LL +     println!("val='{var}'");
+   |
+
+error: variables can be used directly in the `format!` string
+  --> $DIR/uninlined_format_args_panic.rs:14:9
+   |
+LL |         panic!("p1 {}", var);
+   |         ^^^^^^^^^^^^^^^^^^^^
+   |
+help: change this to
+   |
+LL -         panic!("p1 {}", var);
+LL +         panic!("p1 {var}");
+   |
+
+error: variables can be used directly in the `format!` string
+  --> $DIR/uninlined_format_args_panic.rs:17:9
+   |
+LL |         panic!("p2 {0}", var);
+   |         ^^^^^^^^^^^^^^^^^^^^^
+   |
+help: change this to
+   |
+LL -         panic!("p2 {0}", var);
+LL +         panic!("p2 {var}");
+   |
+
+error: variables can be used directly in the `format!` string
+  --> $DIR/uninlined_format_args_panic.rs:20:9
+   |
+LL |         panic!("p3 {var}", var = var);
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: change this to
+   |
+LL -         panic!("p3 {var}", var = var);
+LL +         panic!("p3 {var}");
+   |
+
+error: aborting due to 4 previous errors
+
diff --git a/src/tools/clippy/tests/ui/uninlined_format_args_panic.rs b/src/tools/clippy/tests/ui/uninlined_format_args_panic.rs
new file mode 100644
index 000000000000..6421c5bbed2f
--- /dev/null
+++ b/src/tools/clippy/tests/ui/uninlined_format_args_panic.rs
@@ -0,0 +1,29 @@
+// revisions: edition2018 edition2021
+//[edition2018] edition:2018
+//[edition2021] edition:2021
+// run-rustfix
+
+#![warn(clippy::uninlined_format_args)]
+
+fn main() {
+    let var = 1;
+
+    println!("val='{}'", var);
+
+    if var > 0 {
+        panic!("p1 {}", var);
+    }
+    if var > 0 {
+        panic!("p2 {0}", var);
+    }
+    if var > 0 {
+        panic!("p3 {var}", var = var);
+    }
+
+    #[allow(non_fmt_panics)]
+    {
+        if var > 0 {
+            panic!("p4 {var}");
+        }
+    }
+}
diff --git a/src/tools/clippy/tests/ui/unnecessary_cast.fixed b/src/tools/clippy/tests/ui/unnecessary_cast.fixed
index 94dc96427263..ec8c6abfab91 100644
--- a/src/tools/clippy/tests/ui/unnecessary_cast.fixed
+++ b/src/tools/clippy/tests/ui/unnecessary_cast.fixed
@@ -111,4 +111,8 @@ mod fixable {
 
         let _num = foo();
     }
+
+    fn issue_9603() {
+        let _: f32 = -0x400 as f32;
+    }
 }
diff --git a/src/tools/clippy/tests/ui/unnecessary_cast.rs b/src/tools/clippy/tests/ui/unnecessary_cast.rs
index e5150256f69a..5213cdc269bd 100644
--- a/src/tools/clippy/tests/ui/unnecessary_cast.rs
+++ b/src/tools/clippy/tests/ui/unnecessary_cast.rs
@@ -111,4 +111,8 @@ mod fixable {
 
         let _num = foo() as f32;
     }
+
+    fn issue_9603() {
+        let _: f32 = -0x400 as f32;
+    }
 }
diff --git a/src/tools/clippy/tests/ui/unnecessary_to_owned.fixed b/src/tools/clippy/tests/ui/unnecessary_to_owned.fixed
index f97583aa22f9..fe09aad06bc8 100644
--- a/src/tools/clippy/tests/ui/unnecessary_to_owned.fixed
+++ b/src/tools/clippy/tests/ui/unnecessary_to_owned.fixed
@@ -1,6 +1,6 @@
 // run-rustfix
 
-#![allow(clippy::ptr_arg)]
+#![allow(clippy::needless_borrow, clippy::ptr_arg)]
 #![warn(clippy::unnecessary_to_owned)]
 #![feature(custom_inner_attributes)]
 
diff --git a/src/tools/clippy/tests/ui/unnecessary_to_owned.rs b/src/tools/clippy/tests/ui/unnecessary_to_owned.rs
index aa5394a56579..3de6d0903c0f 100644
--- a/src/tools/clippy/tests/ui/unnecessary_to_owned.rs
+++ b/src/tools/clippy/tests/ui/unnecessary_to_owned.rs
@@ -1,6 +1,6 @@
 // run-rustfix
 
-#![allow(clippy::ptr_arg)]
+#![allow(clippy::needless_borrow, clippy::ptr_arg)]
 #![warn(clippy::unnecessary_to_owned)]
 #![feature(custom_inner_attributes)]
 
diff --git a/src/tools/clippy/tests/ui/unnested_or_patterns.fixed b/src/tools/clippy/tests/ui/unnested_or_patterns.fixed
index c223b5bc711b..9786c7b12128 100644
--- a/src/tools/clippy/tests/ui/unnested_or_patterns.fixed
+++ b/src/tools/clippy/tests/ui/unnested_or_patterns.fixed
@@ -1,9 +1,9 @@
 // run-rustfix
 
-#![feature(box_patterns)]
+#![feature(box_patterns, custom_inner_attributes)]
 #![warn(clippy::unnested_or_patterns)]
 #![allow(clippy::cognitive_complexity, clippy::match_ref_pats, clippy::upper_case_acronyms)]
-#![allow(unreachable_patterns, irrefutable_let_patterns, unused_variables)]
+#![allow(unreachable_patterns, irrefutable_let_patterns, unused)]
 
 fn main() {
     // Should be ignored by this lint, as nesting requires more characters.
@@ -33,3 +33,15 @@ fn main() {
     if let S { x: 0 | 1, y } = (S { x: 0, y: 1 }) {}
     if let S { x: 0, y, .. } | S { y, x: 1 } = (S { x: 0, y: 1 }) {}
 }
+
+fn msrv_1_52() {
+    #![clippy::msrv = "1.52"]
+
+    if let [1] | [52] = [0] {}
+}
+
+fn msrv_1_53() {
+    #![clippy::msrv = "1.53"]
+
+    if let [1 | 53] = [0] {}
+}
diff --git a/src/tools/clippy/tests/ui/unnested_or_patterns.rs b/src/tools/clippy/tests/ui/unnested_or_patterns.rs
index 04cd11036e4e..f57322396d4a 100644
--- a/src/tools/clippy/tests/ui/unnested_or_patterns.rs
+++ b/src/tools/clippy/tests/ui/unnested_or_patterns.rs
@@ -1,9 +1,9 @@
 // run-rustfix
 
-#![feature(box_patterns)]
+#![feature(box_patterns, custom_inner_attributes)]
 #![warn(clippy::unnested_or_patterns)]
 #![allow(clippy::cognitive_complexity, clippy::match_ref_pats, clippy::upper_case_acronyms)]
-#![allow(unreachable_patterns, irrefutable_let_patterns, unused_variables)]
+#![allow(unreachable_patterns, irrefutable_let_patterns, unused)]
 
 fn main() {
     // Should be ignored by this lint, as nesting requires more characters.
@@ -33,3 +33,15 @@ fn main() {
     if let S { x: 0, y } | S { y, x: 1 } = (S { x: 0, y: 1 }) {}
     if let S { x: 0, y, .. } | S { y, x: 1 } = (S { x: 0, y: 1 }) {}
 }
+
+fn msrv_1_52() {
+    #![clippy::msrv = "1.52"]
+
+    if let [1] | [52] = [0] {}
+}
+
+fn msrv_1_53() {
+    #![clippy::msrv = "1.53"]
+
+    if let [1] | [53] = [0] {}
+}
diff --git a/src/tools/clippy/tests/ui/unnested_or_patterns.stderr b/src/tools/clippy/tests/ui/unnested_or_patterns.stderr
index 453c66cbba8f..fbc12fff0b0e 100644
--- a/src/tools/clippy/tests/ui/unnested_or_patterns.stderr
+++ b/src/tools/clippy/tests/ui/unnested_or_patterns.stderr
@@ -175,5 +175,16 @@ help: nest the patterns
 LL |     if let S { x: 0 | 1, y } = (S { x: 0, y: 1 }) {}
    |            ~~~~~~~~~~~~~~~~~
 
-error: aborting due to 16 previous errors
+error: unnested or-patterns
+  --> $DIR/unnested_or_patterns.rs:46:12
+   |
+LL |     if let [1] | [53] = [0] {}
+   |            ^^^^^^^^^^
+   |
+help: nest the patterns
+   |
+LL |     if let [1 | 53] = [0] {}
+   |            ~~~~~~~~
+
+error: aborting due to 17 previous errors
 
diff --git a/src/tools/clippy/tests/ui/unused_format_specs.fixed b/src/tools/clippy/tests/ui/unused_format_specs.fixed
new file mode 100644
index 000000000000..2930722b42d9
--- /dev/null
+++ b/src/tools/clippy/tests/ui/unused_format_specs.fixed
@@ -0,0 +1,18 @@
+// run-rustfix
+
+#![warn(clippy::unused_format_specs)]
+#![allow(unused)]
+
+fn main() {
+    let f = 1.0f64;
+    println!("{}", 1.0);
+    println!("{f} {f:?}");
+
+    println!("{}", 1);
+}
+
+fn should_not_lint() {
+    let f = 1.0f64;
+    println!("{:.1}", 1.0);
+    println!("{f:.w$} {f:.*?}", 3, w = 2);
+}
diff --git a/src/tools/clippy/tests/ui/unused_format_specs.rs b/src/tools/clippy/tests/ui/unused_format_specs.rs
new file mode 100644
index 000000000000..ee192a000d4b
--- /dev/null
+++ b/src/tools/clippy/tests/ui/unused_format_specs.rs
@@ -0,0 +1,18 @@
+// run-rustfix
+
+#![warn(clippy::unused_format_specs)]
+#![allow(unused)]
+
+fn main() {
+    let f = 1.0f64;
+    println!("{:.}", 1.0);
+    println!("{f:.} {f:.?}");
+
+    println!("{:.}", 1);
+}
+
+fn should_not_lint() {
+    let f = 1.0f64;
+    println!("{:.1}", 1.0);
+    println!("{f:.w$} {f:.*?}", 3, w = 2);
+}
diff --git a/src/tools/clippy/tests/ui/unused_format_specs.stderr b/src/tools/clippy/tests/ui/unused_format_specs.stderr
new file mode 100644
index 000000000000..7231c17e74c1
--- /dev/null
+++ b/src/tools/clippy/tests/ui/unused_format_specs.stderr
@@ -0,0 +1,54 @@
+error: empty precision specifier has no effect
+  --> $DIR/unused_format_specs.rs:8:17
+   |
+LL |     println!("{:.}", 1.0);
+   |                 ^
+   |
+   = note: a precision specifier is not required to format floats
+   = note: `-D clippy::unused-format-specs` implied by `-D warnings`
+help: remove the `.`
+   |
+LL -     println!("{:.}", 1.0);
+LL +     println!("{}", 1.0);
+   |
+
+error: empty precision specifier has no effect
+  --> $DIR/unused_format_specs.rs:9:18
+   |
+LL |     println!("{f:.} {f:.?}");
+   |                  ^
+   |
+   = note: a precision specifier is not required to format floats
+help: remove the `.`
+   |
+LL -     println!("{f:.} {f:.?}");
+LL +     println!("{f} {f:.?}");
+   |
+
+error: empty precision specifier has no effect
+  --> $DIR/unused_format_specs.rs:9:24
+   |
+LL |     println!("{f:.} {f:.?}");
+   |                        ^
+   |
+   = note: a precision specifier is not required to format floats
+help: remove the `.`
+   |
+LL -     println!("{f:.} {f:.?}");
+LL +     println!("{f:.} {f:?}");
+   |
+
+error: empty precision specifier has no effect
+  --> $DIR/unused_format_specs.rs:11:17
+   |
+LL |     println!("{:.}", 1);
+   |                 ^
+   |
+help: remove the `.`
+   |
+LL -     println!("{:.}", 1);
+LL +     println!("{}", 1);
+   |
+
+error: aborting due to 4 previous errors
+
diff --git a/src/tools/clippy/tests/ui/unused_format_specs_unfixable.rs b/src/tools/clippy/tests/ui/unused_format_specs_unfixable.rs
new file mode 100644
index 000000000000..78601a3483d3
--- /dev/null
+++ b/src/tools/clippy/tests/ui/unused_format_specs_unfixable.rs
@@ -0,0 +1,30 @@
+#![warn(clippy::unused_format_specs)]
+#![allow(unused)]
+
+macro_rules! format_args_from_macro {
+    () => {
+        format_args!("from macro")
+    };
+}
+
+fn main() {
+    // prints `.`, not `     .`
+    println!("{:5}.", format_args!(""));
+    //prints `abcde`, not `abc`
+    println!("{:.3}", format_args!("abcde"));
+
+    println!("{:5}.", format_args_from_macro!());
+
+    let args = format_args!("");
+    println!("{args:5}");
+}
+
+fn should_not_lint() {
+    println!("{}", format_args!(""));
+    // Technically the same as `{}`, but the `format_args` docs specifically mention that you can use
+    // debug formatting so allow it
+    println!("{:?}", format_args!(""));
+
+    let args = format_args!("");
+    println!("{args}");
+}
diff --git a/src/tools/clippy/tests/ui/unused_format_specs_unfixable.stderr b/src/tools/clippy/tests/ui/unused_format_specs_unfixable.stderr
new file mode 100644
index 000000000000..9f1890282e6a
--- /dev/null
+++ b/src/tools/clippy/tests/ui/unused_format_specs_unfixable.stderr
@@ -0,0 +1,69 @@
+error: format specifiers have no effect on `format_args!()`
+  --> $DIR/unused_format_specs_unfixable.rs:12:15
+   |
+LL |     println!("{:5}.", format_args!(""));
+   |               ^^^^
+   |
+   = note: `-D clippy::unused-format-specs` implied by `-D warnings`
+help: for the width to apply consider using `format!()`
+   |
+LL |     println!("{:5}.", format!(""));
+   |                       ~~~~~~
+help: if the current behavior is intentional, remove the format specifiers
+   |
+LL -     println!("{:5}.", format_args!(""));
+LL +     println!("{}.", format_args!(""));
+   |
+
+error: format specifiers have no effect on `format_args!()`
+  --> $DIR/unused_format_specs_unfixable.rs:14:15
+   |
+LL |     println!("{:.3}", format_args!("abcde"));
+   |               ^^^^^
+   |
+help: for the precision to apply consider using `format!()`
+   |
+LL |     println!("{:.3}", format!("abcde"));
+   |                       ~~~~~~
+help: if the current behavior is intentional, remove the format specifiers
+   |
+LL -     println!("{:.3}", format_args!("abcde"));
+LL +     println!("{}", format_args!("abcde"));
+   |
+
+error: format specifiers have no effect on `format_args!()`
+  --> $DIR/unused_format_specs_unfixable.rs:16:15
+   |
+LL |     println!("{:5}.", format_args_from_macro!());
+   |               ^^^^
+   |
+help: for the width to apply consider using `format!()`
+  --> $DIR/unused_format_specs_unfixable.rs:16:17
+   |
+LL |     println!("{:5}.", format_args_from_macro!());
+   |                 ^
+help: if the current behavior is intentional, remove the format specifiers
+   |
+LL -     println!("{:5}.", format_args_from_macro!());
+LL +     println!("{}.", format_args_from_macro!());
+   |
+
+error: format specifiers have no effect on `format_args!()`
+  --> $DIR/unused_format_specs_unfixable.rs:19:15
+   |
+LL |     println!("{args:5}");
+   |               ^^^^^^^^
+   |
+help: for the width to apply consider using `format!()`
+  --> $DIR/unused_format_specs_unfixable.rs:19:21
+   |
+LL |     println!("{args:5}");
+   |                     ^
+help: if the current behavior is intentional, remove the format specifiers
+   |
+LL -     println!("{args:5}");
+LL +     println!("{args}");
+   |
+
+error: aborting due to 4 previous errors
+
diff --git a/src/tools/clippy/tests/ui/use_self.fixed b/src/tools/clippy/tests/ui/use_self.fixed
index 37986187da17..3b54fe9d5ff3 100644
--- a/src/tools/clippy/tests/ui/use_self.fixed
+++ b/src/tools/clippy/tests/ui/use_self.fixed
@@ -1,6 +1,7 @@
 // run-rustfix
 // aux-build:proc_macro_derive.rs
 
+#![feature(custom_inner_attributes)]
 #![warn(clippy::use_self)]
 #![allow(dead_code, unreachable_code)]
 #![allow(
@@ -617,3 +618,35 @@ mod issue6902 {
         Bar = 1,
     }
 }
+
+fn msrv_1_36() {
+    #![clippy::msrv = "1.36"]
+
+    enum E {
+        A,
+    }
+
+    impl E {
+        fn foo(self) {
+            match self {
+                E::A => {},
+            }
+        }
+    }
+}
+
+fn msrv_1_37() {
+    #![clippy::msrv = "1.37"]
+
+    enum E {
+        A,
+    }
+
+    impl E {
+        fn foo(self) {
+            match self {
+                Self::A => {},
+            }
+        }
+    }
+}
diff --git a/src/tools/clippy/tests/ui/use_self.rs b/src/tools/clippy/tests/ui/use_self.rs
index 1b2b3337c92e..bf87633cd2d8 100644
--- a/src/tools/clippy/tests/ui/use_self.rs
+++ b/src/tools/clippy/tests/ui/use_self.rs
@@ -1,6 +1,7 @@
 // run-rustfix
 // aux-build:proc_macro_derive.rs
 
+#![feature(custom_inner_attributes)]
 #![warn(clippy::use_self)]
 #![allow(dead_code, unreachable_code)]
 #![allow(
@@ -617,3 +618,35 @@ mod issue6902 {
         Bar = 1,
     }
 }
+
+fn msrv_1_36() {
+    #![clippy::msrv = "1.36"]
+
+    enum E {
+        A,
+    }
+
+    impl E {
+        fn foo(self) {
+            match self {
+                E::A => {},
+            }
+        }
+    }
+}
+
+fn msrv_1_37() {
+    #![clippy::msrv = "1.37"]
+
+    enum E {
+        A,
+    }
+
+    impl E {
+        fn foo(self) {
+            match self {
+                E::A => {},
+            }
+        }
+    }
+}
diff --git a/src/tools/clippy/tests/ui/use_self.stderr b/src/tools/clippy/tests/ui/use_self.stderr
index f06bb959b3bd..16fb0609242c 100644
--- a/src/tools/clippy/tests/ui/use_self.stderr
+++ b/src/tools/clippy/tests/ui/use_self.stderr
@@ -1,5 +1,5 @@
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:22:21
+  --> $DIR/use_self.rs:23:21
    |
 LL |         fn new() -> Foo {
    |                     ^^^ help: use the applicable keyword: `Self`
@@ -7,244 +7,250 @@ LL |         fn new() -> Foo {
    = note: `-D clippy::use-self` implied by `-D warnings`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:23:13
+  --> $DIR/use_self.rs:24:13
    |
 LL |             Foo {}
    |             ^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:25:22
+  --> $DIR/use_self.rs:26:22
    |
 LL |         fn test() -> Foo {
    |                      ^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:26:13
+  --> $DIR/use_self.rs:27:13
    |
 LL |             Foo::new()
    |             ^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:31:25
+  --> $DIR/use_self.rs:32:25
    |
 LL |         fn default() -> Foo {
    |                         ^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:32:13
+  --> $DIR/use_self.rs:33:13
    |
 LL |             Foo::new()
    |             ^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:97:24
+  --> $DIR/use_self.rs:98:24
    |
 LL |         fn bad(foos: &[Foo]) -> impl Iterator<Item = &Foo> {
    |                        ^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:97:55
+  --> $DIR/use_self.rs:98:55
    |
 LL |         fn bad(foos: &[Foo]) -> impl Iterator<Item = &Foo> {
    |                                                       ^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:112:13
+  --> $DIR/use_self.rs:113:13
    |
 LL |             TS(0)
    |             ^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:147:29
+  --> $DIR/use_self.rs:148:29
    |
 LL |                 fn bar() -> Bar {
    |                             ^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:148:21
+  --> $DIR/use_self.rs:149:21
    |
 LL |                     Bar { foo: Foo {} }
    |                     ^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:159:21
+  --> $DIR/use_self.rs:160:21
    |
 LL |         fn baz() -> Foo {
    |                     ^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:160:13
+  --> $DIR/use_self.rs:161:13
    |
 LL |             Foo {}
    |             ^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:177:21
+  --> $DIR/use_self.rs:178:21
    |
 LL |             let _ = Enum::B(42);
    |                     ^^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:178:21
+  --> $DIR/use_self.rs:179:21
    |
 LL |             let _ = Enum::C { field: true };
    |                     ^^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:179:21
+  --> $DIR/use_self.rs:180:21
    |
 LL |             let _ = Enum::A;
    |                     ^^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:221:13
+  --> $DIR/use_self.rs:222:13
    |
 LL |             nested::A::fun_1();
    |             ^^^^^^^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:222:13
+  --> $DIR/use_self.rs:223:13
    |
 LL |             nested::A::A;
    |             ^^^^^^^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:224:13
+  --> $DIR/use_self.rs:225:13
    |
 LL |             nested::A {};
    |             ^^^^^^^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:243:13
+  --> $DIR/use_self.rs:244:13
    |
 LL |             TestStruct::from_something()
    |             ^^^^^^^^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:257:25
+  --> $DIR/use_self.rs:258:25
    |
 LL |         async fn g() -> S {
    |                         ^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:258:13
+  --> $DIR/use_self.rs:259:13
    |
 LL |             S {}
    |             ^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:262:16
+  --> $DIR/use_self.rs:263:16
    |
 LL |             &p[S::A..S::B]
    |                ^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:262:22
+  --> $DIR/use_self.rs:263:22
    |
 LL |             &p[S::A..S::B]
    |                      ^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:285:29
+  --> $DIR/use_self.rs:286:29
    |
 LL |         fn foo(value: T) -> Foo<T> {
    |                             ^^^^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:286:13
+  --> $DIR/use_self.rs:287:13
    |
 LL |             Foo::<T> { value }
    |             ^^^^^^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:458:13
+  --> $DIR/use_self.rs:459:13
    |
 LL |             A::new::<submod::B>(submod::B {})
    |             ^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:495:13
+  --> $DIR/use_self.rs:496:13
    |
 LL |             S2::new()
    |             ^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:532:17
+  --> $DIR/use_self.rs:533:17
    |
 LL |                 Foo::Bar => unimplemented!(),
    |                 ^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:533:17
+  --> $DIR/use_self.rs:534:17
    |
 LL |                 Foo::Baz => unimplemented!(),
    |                 ^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:539:20
+  --> $DIR/use_self.rs:540:20
    |
 LL |             if let Foo::Bar = self {
    |                    ^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:563:17
+  --> $DIR/use_self.rs:564:17
    |
 LL |                 Something::Num(n) => *n,
    |                 ^^^^^^^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:564:17
+  --> $DIR/use_self.rs:565:17
    |
 LL |                 Something::TupleNums(n, _m) => *n,
    |                 ^^^^^^^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:565:17
+  --> $DIR/use_self.rs:566:17
    |
 LL |                 Something::StructNums { one, two: _ } => *one,
    |                 ^^^^^^^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:571:17
+  --> $DIR/use_self.rs:572:17
    |
 LL |                 crate::issue8845::Something::Num(n) => *n,
    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:572:17
+  --> $DIR/use_self.rs:573:17
    |
 LL |                 crate::issue8845::Something::TupleNums(n, _m) => *n,
    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:573:17
+  --> $DIR/use_self.rs:574:17
    |
 LL |                 crate::issue8845::Something::StructNums { one, two: _ } => *one,
    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:589:17
+  --> $DIR/use_self.rs:590:17
    |
 LL |             let Foo(x) = self;
    |                 ^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:594:17
+  --> $DIR/use_self.rs:595:17
    |
 LL |             let crate::issue8845::Foo(x) = self;
    |                 ^^^^^^^^^^^^^^^^^^^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:601:17
+  --> $DIR/use_self.rs:602:17
    |
 LL |             let Bar { x, .. } = self;
    |                 ^^^ help: use the applicable keyword: `Self`
 
 error: unnecessary structure name repetition
-  --> $DIR/use_self.rs:606:17
+  --> $DIR/use_self.rs:607:17
    |
 LL |             let crate::issue8845::Bar { x, .. } = self;
    |                 ^^^^^^^^^^^^^^^^^^^^^ help: use the applicable keyword: `Self`
 
-error: aborting due to 41 previous errors
+error: unnecessary structure name repetition
+  --> $DIR/use_self.rs:648:17
+   |
+LL |                 E::A => {},
+   |                 ^ help: use the applicable keyword: `Self`
+
+error: aborting due to 42 previous errors
 
diff --git a/src/tools/clippy/tests/versioncheck.rs b/src/tools/clippy/tests/versioncheck.rs
index 9e07769a8e4f..a6d8d0307ce5 100644
--- a/src/tools/clippy/tests/versioncheck.rs
+++ b/src/tools/clippy/tests/versioncheck.rs
@@ -48,7 +48,7 @@ fn check_that_clippy_has_the_same_major_version_as_rustc() {
     // `RUSTC_REAL` if Clippy is build in the Rust repo with `./x.py`.
     let rustc = std::env::var("RUSTC_REAL").unwrap_or_else(|_| "rustc".to_string());
     let rustc_version = String::from_utf8(
-        std::process::Command::new(&rustc)
+        std::process::Command::new(rustc)
             .arg("--version")
             .output()
             .expect("failed to run `rustc --version`")
diff --git a/src/tools/clippy/util/gh-pages/index.html b/src/tools/clippy/util/gh-pages/index.html
index c5d602ea3035..e46ad2c6e0ee 100644
--- a/src/tools/clippy/util/gh-pages/index.html
+++ b/src/tools/clippy/util/gh-pages/index.html
@@ -442,6 +442,12 @@ Otherwise, have a great day =^.^=
                                         All
                                     </label>
                                 </li>
+                                <li class="checkbox">
+                                    <label ng-click="resetGroupsToDefault()">
+                                        <input type="checkbox" class="invisible" />
+                                        Default
+                                    </label>
+                                </li>
                                 <li class="checkbox">
                                     <label ng-click="toggleGroups(false)">
                                         <input type="checkbox" class="invisible" />
diff --git a/src/tools/clippy/util/gh-pages/script.js b/src/tools/clippy/util/gh-pages/script.js
index 366e7c8843f2..1c16ecd6b0b1 100644
--- a/src/tools/clippy/util/gh-pages/script.js
+++ b/src/tools/clippy/util/gh-pages/script.js
@@ -114,7 +114,7 @@
                 return $scope.levels[lint.level];
             };
 
-            var GROUPS_FILTER_DEFAULT = {
+            const GROUPS_FILTER_DEFAULT = {
                 cargo: true,
                 complexity: true,
                 correctness: true,
@@ -125,8 +125,12 @@
                 restriction: true,
                 style: true,
                 suspicious: true,
+            }
+
+            $scope.groups = {
+                ...GROUPS_FILTER_DEFAULT
             };
-            $scope.groups = GROUPS_FILTER_DEFAULT;
+
             const THEMES_DEFAULT = {
                 light: "Light",
                 rust: "Rust",
@@ -164,6 +168,13 @@
                 }
             };
 
+            $scope.resetGroupsToDefault = function () {
+                const groups = $scope.groups;
+                for (const [key, value] of Object.entries(GROUPS_FILTER_DEFAULT)) {
+                    groups[key] = value;
+                }
+            };
+
             $scope.selectedValuesCount = function (obj) {
                 return Object.values(obj).filter(x => x).length;
             }
diff --git a/src/tools/compiletest/Cargo.toml b/src/tools/compiletest/Cargo.toml
index 41f97e4326a9..1911f0f9c941 100644
--- a/src/tools/compiletest/Cargo.toml
+++ b/src/tools/compiletest/Cargo.toml
@@ -8,6 +8,7 @@ colored = "2"
 diff = "0.1.10"
 unified-diff = "0.2.1"
 getopts = "0.2"
+miropt-test-tools = { path = "../miropt-test-tools" }
 tracing = "0.1"
 tracing-subscriber = { version = "0.3.3", default-features = false, features = ["fmt", "env-filter", "smallvec", "parking_lot", "ansi"] }
 regex = "1.0"
diff --git a/src/tools/compiletest/src/common.rs b/src/tools/compiletest/src/common.rs
index b9ac6c9f3641..9a432f11f82f 100644
--- a/src/tools/compiletest/src/common.rs
+++ b/src/tools/compiletest/src/common.rs
@@ -2,11 +2,12 @@ pub use self::Mode::*;
 
 use std::ffi::OsString;
 use std::fmt;
+use std::iter;
 use std::path::{Path, PathBuf};
 use std::process::Command;
 use std::str::FromStr;
 
-use crate::util::PathBufExt;
+use crate::util::{add_dylib_path, PathBufExt};
 use lazycell::LazyCell;
 use test::ColorConfig;
 
@@ -269,10 +270,10 @@ pub struct Config {
     pub runtool: Option<String>,
 
     /// Flags to pass to the compiler when building for the host
-    pub host_rustcflags: Option<String>,
+    pub host_rustcflags: Vec<String>,
 
     /// Flags to pass to the compiler when building for the target
-    pub target_rustcflags: Option<String>,
+    pub target_rustcflags: Vec<String>,
 
     /// Whether tests should be optimized by default. Individual test-suites and test files may
     /// override this setting.
@@ -385,8 +386,7 @@ impl Config {
     }
 
     fn target_cfg(&self) -> &TargetCfg {
-        self.target_cfg
-            .borrow_with(|| TargetCfg::new(&self.rustc_path, &self.target, &self.target_rustcflags))
+        self.target_cfg.borrow_with(|| TargetCfg::new(self))
     }
 
     pub fn matches_arch(&self, arch: &str) -> bool {
@@ -457,21 +457,23 @@ pub enum Endian {
 }
 
 impl TargetCfg {
-    fn new(rustc_path: &Path, target: &str, target_rustcflags: &Option<String>) -> TargetCfg {
-        let output = match Command::new(rustc_path)
+    fn new(config: &Config) -> TargetCfg {
+        let mut command = Command::new(&config.rustc_path);
+        add_dylib_path(&mut command, iter::once(&config.compile_lib_path));
+        let output = match command
             .arg("--print=cfg")
             .arg("--target")
-            .arg(target)
-            .args(target_rustcflags.into_iter().map(|s| s.split_whitespace()).flatten())
+            .arg(&config.target)
+            .args(&config.target_rustcflags)
             .output()
         {
             Ok(output) => output,
-            Err(e) => panic!("error: failed to get cfg info from {:?}: {e}", rustc_path),
+            Err(e) => panic!("error: failed to get cfg info from {:?}: {e}", config.rustc_path),
         };
         if !output.status.success() {
             panic!(
                 "error: failed to get cfg info from {:?}\n--- stdout\n{}\n--- stderr\n{}",
-                rustc_path,
+                config.rustc_path,
                 String::from_utf8(output.stdout).unwrap(),
                 String::from_utf8(output.stderr).unwrap(),
             );
diff --git a/src/tools/compiletest/src/main.rs b/src/tools/compiletest/src/main.rs
index a8cf6623f35d..19cf54780c1f 100644
--- a/src/tools/compiletest/src/main.rs
+++ b/src/tools/compiletest/src/main.rs
@@ -254,8 +254,8 @@ pub fn parse_config(args: Vec<String>) -> Config {
         }),
         logfile: matches.opt_str("logfile").map(|s| PathBuf::from(&s)),
         runtool: matches.opt_str("runtool"),
-        host_rustcflags: Some(matches.opt_strs("host-rustcflags").join(" ")),
-        target_rustcflags: Some(matches.opt_strs("target-rustcflags").join(" ")),
+        host_rustcflags: matches.opt_strs("host-rustcflags"),
+        target_rustcflags: matches.opt_strs("target-rustcflags"),
         optimize_tests: matches.opt_present("optimize-tests"),
         target,
         host: opt_str2(matches.opt_str("host")),
@@ -322,8 +322,8 @@ pub fn log_config(config: &Config) {
         format!("force_pass_mode: {}", opt_str(&config.force_pass_mode.map(|m| format!("{}", m))),),
     );
     logv(c, format!("runtool: {}", opt_str(&config.runtool)));
-    logv(c, format!("host-rustcflags: {}", opt_str(&config.host_rustcflags)));
-    logv(c, format!("target-rustcflags: {}", opt_str(&config.target_rustcflags)));
+    logv(c, format!("host-rustcflags: {:?}", config.host_rustcflags));
+    logv(c, format!("target-rustcflags: {:?}", config.target_rustcflags));
     logv(c, format!("target: {}", config.target));
     logv(c, format!("host: {}", config.host));
     logv(c, format!("android-cross-path: {:?}", config.android_cross_path.display()));
diff --git a/src/tools/compiletest/src/runtest.rs b/src/tools/compiletest/src/runtest.rs
index 8f289876f730..8d8ca101cd03 100644
--- a/src/tools/compiletest/src/runtest.rs
+++ b/src/tools/compiletest/src/runtest.rs
@@ -13,7 +13,7 @@ use crate::errors::{self, Error, ErrorKind};
 use crate::header::TestProps;
 use crate::json;
 use crate::read2::read2_abbreviated;
-use crate::util::{logv, PathBufExt};
+use crate::util::{add_dylib_path, dylib_env_var, logv, PathBufExt};
 use crate::ColorConfig;
 use regex::{Captures, Regex};
 use rustfix::{apply_suggestions, get_suggestions_from_json, Filter};
@@ -26,6 +26,7 @@ use std::fs::{self, create_dir_all, File, OpenOptions};
 use std::hash::{Hash, Hasher};
 use std::io::prelude::*;
 use std::io::{self, BufReader};
+use std::iter;
 use std::path::{Path, PathBuf};
 use std::process::{Child, Command, ExitStatus, Output, Stdio};
 use std::str;
@@ -72,19 +73,6 @@ fn disable_error_reporting<F: FnOnce() -> R, R>(f: F) -> R {
     f()
 }
 
-/// The name of the environment variable that holds dynamic library locations.
-pub fn dylib_env_var() -> &'static str {
-    if cfg!(windows) {
-        "PATH"
-    } else if cfg!(target_os = "macos") {
-        "DYLD_LIBRARY_PATH"
-    } else if cfg!(target_os = "haiku") {
-        "LIBRARY_PATH"
-    } else {
-        "LD_LIBRARY_PATH"
-    }
-}
-
 /// The platform-specific library name
 pub fn get_lib_name(lib: &str, dylib: bool) -> String {
     // In some casess (e.g. MUSL), we build a static
@@ -220,11 +208,13 @@ enum WillExecute {
     Disabled,
 }
 
-/// Should `--emit metadata` be used?
+/// What value should be passed to `--emit`?
 #[derive(Copy, Clone)]
-enum EmitMetadata {
-    Yes,
-    No,
+enum Emit {
+    None,
+    Metadata,
+    LlvmIr,
+    Asm,
 }
 
 impl<'test> TestCx<'test> {
@@ -424,7 +414,7 @@ impl<'test> TestCx<'test> {
         }
 
         let should_run = self.run_if_enabled();
-        let mut proc_res = self.compile_test(should_run, EmitMetadata::No);
+        let mut proc_res = self.compile_test(should_run, Emit::None);
 
         if !proc_res.status.success() {
             self.fatal_proc_rec("compilation failed!", &proc_res);
@@ -558,10 +548,7 @@ impl<'test> TestCx<'test> {
             .arg(&aux_dir)
             .args(&self.props.compile_flags)
             .envs(self.props.rustc_env.clone());
-        self.maybe_add_external_args(
-            &mut rustc,
-            self.split_maybe_args(&self.config.target_rustcflags),
-        );
+        self.maybe_add_external_args(&mut rustc, &self.config.target_rustcflags);
 
         let src = match read_from {
             ReadFrom::Stdin(src) => Some(src),
@@ -629,10 +616,7 @@ impl<'test> TestCx<'test> {
             .arg("-L")
             .arg(aux_dir);
         self.set_revision_flags(&mut rustc);
-        self.maybe_add_external_args(
-            &mut rustc,
-            self.split_maybe_args(&self.config.target_rustcflags),
-        );
+        self.maybe_add_external_args(&mut rustc, &self.config.target_rustcflags);
         rustc.args(&self.props.compile_flags);
 
         self.compose_and_run_compiler(rustc, Some(src))
@@ -676,7 +660,7 @@ impl<'test> TestCx<'test> {
 
         // compile test file (it should have 'compile-flags:-g' in the header)
         let should_run = self.run_if_enabled();
-        let compile_result = self.compile_test(should_run, EmitMetadata::No);
+        let compile_result = self.compile_test(should_run, Emit::None);
         if !compile_result.status.success() {
             self.fatal_proc_rec("compilation failed!", &compile_result);
         }
@@ -796,7 +780,7 @@ impl<'test> TestCx<'test> {
 
         // compile test file (it should have 'compile-flags:-g' in the header)
         let should_run = self.run_if_enabled();
-        let compiler_run_result = self.compile_test(should_run, EmitMetadata::No);
+        let compiler_run_result = self.compile_test(should_run, Emit::None);
         if !compiler_run_result.status.success() {
             self.fatal_proc_rec("compilation failed!", &compiler_run_result);
         }
@@ -1028,7 +1012,7 @@ impl<'test> TestCx<'test> {
     fn run_debuginfo_lldb_test_no_opt(&self) {
         // compile test file (it should have 'compile-flags:-g' in the header)
         let should_run = self.run_if_enabled();
-        let compile_result = self.compile_test(should_run, EmitMetadata::No);
+        let compile_result = self.compile_test(should_run, Emit::None);
         if !compile_result.status.success() {
             self.fatal_proc_rec("compilation failed!", &compile_result);
         }
@@ -1186,23 +1170,14 @@ impl<'test> TestCx<'test> {
         ProcRes { status, stdout: out, stderr: err, cmdline: format!("{:?}", cmd) }
     }
 
-    fn cleanup_debug_info_options(&self, options: &Option<String>) -> Option<String> {
-        if options.is_none() {
-            return None;
-        }
-
+    fn cleanup_debug_info_options(&self, options: &Vec<String>) -> Vec<String> {
         // Remove options that are either unwanted (-O) or may lead to duplicates due to RUSTFLAGS.
         let options_to_remove = ["-O".to_owned(), "-g".to_owned(), "--debuginfo".to_owned()];
-        let new_options = self
-            .split_maybe_args(options)
-            .into_iter()
-            .filter(|x| !options_to_remove.contains(x))
-            .collect::<Vec<String>>();
 
-        Some(new_options.join(" "))
+        options.iter().filter(|x| !options_to_remove.contains(x)).map(|x| x.clone()).collect()
     }
 
-    fn maybe_add_external_args(&self, cmd: &mut Command, args: Vec<String>) {
+    fn maybe_add_external_args(&self, cmd: &mut Command, args: &Vec<String>) {
         // Filter out the arguments that should not be added by runtest here.
         //
         // Notable use-cases are: do not add our optimisation flag if
@@ -1453,21 +1428,21 @@ impl<'test> TestCx<'test> {
         }
     }
 
-    fn should_emit_metadata(&self, pm: Option<PassMode>) -> EmitMetadata {
+    fn should_emit_metadata(&self, pm: Option<PassMode>) -> Emit {
         match (pm, self.props.fail_mode, self.config.mode) {
-            (Some(PassMode::Check), ..) | (_, Some(FailMode::Check), Ui) => EmitMetadata::Yes,
-            _ => EmitMetadata::No,
+            (Some(PassMode::Check), ..) | (_, Some(FailMode::Check), Ui) => Emit::Metadata,
+            _ => Emit::None,
         }
     }
 
-    fn compile_test(&self, will_execute: WillExecute, emit_metadata: EmitMetadata) -> ProcRes {
-        self.compile_test_general(will_execute, emit_metadata, self.props.local_pass_mode())
+    fn compile_test(&self, will_execute: WillExecute, emit: Emit) -> ProcRes {
+        self.compile_test_general(will_execute, emit, self.props.local_pass_mode())
     }
 
     fn compile_test_general(
         &self,
         will_execute: WillExecute,
-        emit_metadata: EmitMetadata,
+        emit: Emit,
         local_pm: Option<PassMode>,
     ) -> ProcRes {
         // Only use `make_exe_name` when the test ends up being executed.
@@ -1499,10 +1474,13 @@ impl<'test> TestCx<'test> {
             _ => AllowUnused::No,
         };
 
-        let mut rustc =
-            self.make_compile_args(&self.testpaths.file, output_file, emit_metadata, allow_unused);
-
-        rustc.arg("-L").arg(&self.aux_output_dir_name());
+        let rustc = self.make_compile_args(
+            &self.testpaths.file,
+            output_file,
+            emit,
+            allow_unused,
+            LinkToAux::Yes,
+        );
 
         self.compose_and_run_compiler(rustc, None)
     }
@@ -1729,8 +1707,13 @@ impl<'test> TestCx<'test> {
         // Create the directory for the stdout/stderr files.
         create_dir_all(aux_cx.output_base_dir()).unwrap();
         let input_file = &aux_testpaths.file;
-        let mut aux_rustc =
-            aux_cx.make_compile_args(input_file, aux_output, EmitMetadata::No, AllowUnused::No);
+        let mut aux_rustc = aux_cx.make_compile_args(
+            input_file,
+            aux_output,
+            Emit::None,
+            AllowUnused::No,
+            LinkToAux::No,
+        );
 
         for key in &aux_props.unset_rustc_env {
             aux_rustc.env_remove(key);
@@ -1826,16 +1809,7 @@ impl<'test> TestCx<'test> {
 
         // Need to be sure to put both the lib_path and the aux path in the dylib
         // search path for the child.
-        let mut path =
-            env::split_paths(&env::var_os(dylib_env_var()).unwrap_or_default()).collect::<Vec<_>>();
-        if let Some(p) = aux_path {
-            path.insert(0, PathBuf::from(p))
-        }
-        path.insert(0, PathBuf::from(lib_path));
-
-        // Add the new dylib search path var
-        let newpath = env::join_paths(&path).unwrap();
-        command.env(dylib_env_var(), newpath);
+        add_dylib_path(&mut command, iter::once(lib_path).chain(aux_path));
 
         let mut child = disable_error_reporting(|| command.spawn())
             .unwrap_or_else(|_| panic!("failed to exec `{:?}`", &command));
@@ -1867,8 +1841,9 @@ impl<'test> TestCx<'test> {
         &self,
         input_file: &Path,
         output_file: TargetLocation,
-        emit_metadata: EmitMetadata,
+        emit: Emit,
         allow_unused: AllowUnused,
+        link_to_aux: LinkToAux,
     ) -> Command {
         let is_aux = input_file.components().map(|c| c.as_os_str()).any(|c| c == "auxiliary");
         let is_rustdoc = self.is_rustdoc() && !is_aux;
@@ -1983,8 +1958,18 @@ impl<'test> TestCx<'test> {
             }
         }
 
-        if let (false, EmitMetadata::Yes) = (is_rustdoc, emit_metadata) {
-            rustc.args(&["--emit", "metadata"]);
+        match emit {
+            Emit::None => {}
+            Emit::Metadata if is_rustdoc => {}
+            Emit::Metadata => {
+                rustc.args(&["--emit", "metadata"]);
+            }
+            Emit::LlvmIr => {
+                rustc.args(&["--emit", "llvm-ir"]);
+            }
+            Emit::Asm => {
+                rustc.args(&["--emit", "asm"]);
+            }
         }
 
         if !is_rustdoc {
@@ -2035,15 +2020,9 @@ impl<'test> TestCx<'test> {
         }
 
         if self.props.force_host {
-            self.maybe_add_external_args(
-                &mut rustc,
-                self.split_maybe_args(&self.config.host_rustcflags),
-            );
+            self.maybe_add_external_args(&mut rustc, &self.config.host_rustcflags);
         } else {
-            self.maybe_add_external_args(
-                &mut rustc,
-                self.split_maybe_args(&self.config.target_rustcflags),
-            );
+            self.maybe_add_external_args(&mut rustc, &self.config.target_rustcflags);
             if !is_rustdoc {
                 if let Some(ref linker) = self.config.linker {
                     rustc.arg(format!("-Clinker={}", linker));
@@ -2056,6 +2035,10 @@ impl<'test> TestCx<'test> {
             rustc.arg("-Ctarget-feature=-crt-static");
         }
 
+        if let LinkToAux::Yes = link_to_aux {
+            rustc.arg("-L").arg(self.aux_output_dir_name());
+        }
+
         rustc.args(&self.props.compile_flags);
 
         rustc
@@ -2247,13 +2230,15 @@ impl<'test> TestCx<'test> {
     // codegen tests (using FileCheck)
 
     fn compile_test_and_save_ir(&self) -> ProcRes {
-        let aux_dir = self.aux_output_dir_name();
-
         let output_file = TargetLocation::ThisDirectory(self.output_base_dir());
         let input_file = &self.testpaths.file;
-        let mut rustc =
-            self.make_compile_args(input_file, output_file, EmitMetadata::No, AllowUnused::No);
-        rustc.arg("-L").arg(aux_dir).arg("--emit=llvm-ir");
+        let rustc = self.make_compile_args(
+            input_file,
+            output_file,
+            Emit::LlvmIr,
+            AllowUnused::No,
+            LinkToAux::Yes,
+        );
 
         self.compose_and_run_compiler(rustc, None)
     }
@@ -2265,14 +2250,11 @@ impl<'test> TestCx<'test> {
 
         let output_file = TargetLocation::ThisFile(output_path.clone());
         let input_file = &self.testpaths.file;
-        let mut rustc =
-            self.make_compile_args(input_file, output_file, EmitMetadata::No, AllowUnused::No);
-
-        rustc.arg("-L").arg(self.aux_output_dir_name());
 
+        let mut emit = Emit::None;
         match self.props.assembly_output.as_ref().map(AsRef::as_ref) {
             Some("emit-asm") => {
-                rustc.arg("--emit=asm");
+                emit = Emit::Asm;
             }
 
             Some("ptx-linker") => {
@@ -2283,6 +2265,9 @@ impl<'test> TestCx<'test> {
             None => self.fatal("missing 'assembly-output' header"),
         }
 
+        let rustc =
+            self.make_compile_args(input_file, output_file, emit, AllowUnused::No, LinkToAux::Yes);
+
         (self.compose_and_run_compiler(rustc, None), output_path)
     }
 
@@ -2407,10 +2392,10 @@ impl<'test> TestCx<'test> {
         let mut rustc = new_rustdoc.make_compile_args(
             &new_rustdoc.testpaths.file,
             output_file,
-            EmitMetadata::No,
+            Emit::None,
             AllowUnused::Yes,
+            LinkToAux::Yes,
         );
-        rustc.arg("-L").arg(&new_rustdoc.aux_output_dir_name());
         new_rustdoc.build_all_auxiliary(&mut rustc);
 
         let proc_res = new_rustdoc.document(&compare_dir);
@@ -2683,7 +2668,7 @@ impl<'test> TestCx<'test> {
     fn run_codegen_units_test(&self) {
         assert!(self.revision.is_none(), "revisions not relevant here");
 
-        let proc_res = self.compile_test(WillExecute::No, EmitMetadata::No);
+        let proc_res = self.compile_test(WillExecute::No, Emit::None);
 
         if !proc_res.status.success() {
             self.fatal_proc_rec("compilation failed!", &proc_res);
@@ -3196,7 +3181,7 @@ impl<'test> TestCx<'test> {
         if let Some(FailMode::Build) = self.props.fail_mode {
             // Make sure a build-fail test cannot fail due to failing analysis (e.g. typeck).
             let pm = Some(PassMode::Check);
-            let proc_res = self.compile_test_general(WillExecute::No, EmitMetadata::Yes, pm);
+            let proc_res = self.compile_test_general(WillExecute::No, Emit::Metadata, pm);
             self.check_if_test_should_compile(&proc_res, pm);
         }
 
@@ -3354,13 +3339,13 @@ impl<'test> TestCx<'test> {
         if self.props.run_rustfix && self.config.compare_mode.is_none() {
             // And finally, compile the fixed code and make sure it both
             // succeeds and has no diagnostics.
-            let mut rustc = self.make_compile_args(
+            let rustc = self.make_compile_args(
                 &self.testpaths.file.with_extension(UI_FIXED),
                 TargetLocation::ThisFile(self.make_exe_name()),
                 emit_metadata,
                 AllowUnused::No,
+                LinkToAux::Yes,
             );
-            rustc.arg("-L").arg(&self.aux_output_dir_name());
             let res = self.compose_and_run_compiler(rustc, None);
             if !res.status.success() {
                 self.fatal_proc_rec("failed to compile fixed code", &res);
@@ -3420,103 +3405,49 @@ impl<'test> TestCx<'test> {
             }
         }
 
-        for l in test_file_contents.lines() {
-            if l.starts_with("// EMIT_MIR ") {
-                let test_name = l.trim_start_matches("// EMIT_MIR ").trim();
-                let mut test_names = test_name.split(' ');
-                // sometimes we specify two files so that we get a diff between the two files
-                let test_name = test_names.next().unwrap();
-                let mut expected_file;
-                let from_file;
-                let to_file;
+        let files = miropt_test_tools::files_for_miropt_test(
+            &self.testpaths.file,
+            self.config.get_pointer_width(),
+        );
 
-                if test_name.ends_with(".diff") {
-                    let trimmed = test_name.trim_end_matches(".diff");
-                    let test_against = format!("{}.after.mir", trimmed);
-                    from_file = format!("{}.before.mir", trimmed);
-                    expected_file = format!("{}{}.diff", trimmed, bit_width);
-                    assert!(
-                        test_names.next().is_none(),
-                        "two mir pass names specified for MIR diff"
-                    );
-                    to_file = Some(test_against);
-                } else if let Some(first_pass) = test_names.next() {
-                    let second_pass = test_names.next().unwrap();
-                    assert!(
-                        test_names.next().is_none(),
-                        "three mir pass names specified for MIR diff"
-                    );
-                    expected_file =
-                        format!("{}{}.{}-{}.diff", test_name, bit_width, first_pass, second_pass);
-                    let second_file = format!("{}.{}.mir", test_name, second_pass);
-                    from_file = format!("{}.{}.mir", test_name, first_pass);
-                    to_file = Some(second_file);
-                } else {
-                    let ext_re = Regex::new(r#"(\.(mir|dot|html))$"#).unwrap();
-                    let cap = ext_re
-                        .captures_iter(test_name)
-                        .next()
-                        .expect("test_name has an invalid extension");
-                    let extension = cap.get(1).unwrap().as_str();
-                    expected_file = format!(
-                        "{}{}{}",
-                        test_name.trim_end_matches(extension),
-                        bit_width,
-                        extension,
-                    );
-                    from_file = test_name.to_string();
-                    assert!(
-                        test_names.next().is_none(),
-                        "two mir pass names specified for MIR dump"
-                    );
-                    to_file = None;
-                };
-                if !expected_file.starts_with(&test_crate) {
-                    expected_file = format!("{}.{}", test_crate, expected_file);
-                }
-                let expected_file = test_dir.join(expected_file);
-
-                let dumped_string = if let Some(after) = to_file {
-                    self.diff_mir_files(from_file.into(), after.into())
-                } else {
-                    let mut output_file = PathBuf::new();
-                    output_file.push(self.get_mir_dump_dir());
-                    output_file.push(&from_file);
-                    debug!(
-                        "comparing the contents of: {} with {}",
+        for miropt_test_tools::MiroptTestFiles { from_file, to_file, expected_file } in files {
+            let dumped_string = if let Some(after) = to_file {
+                self.diff_mir_files(from_file.into(), after.into())
+            } else {
+                let mut output_file = PathBuf::new();
+                output_file.push(self.get_mir_dump_dir());
+                output_file.push(&from_file);
+                debug!(
+                    "comparing the contents of: {} with {}",
+                    output_file.display(),
+                    expected_file.display()
+                );
+                if !output_file.exists() {
+                    panic!(
+                        "Output file `{}` from test does not exist, available files are in `{}`",
                         output_file.display(),
+                        output_file.parent().unwrap().display()
+                    );
+                }
+                self.check_mir_test_timestamp(&from_file, &output_file);
+                let dumped_string = fs::read_to_string(&output_file).unwrap();
+                self.normalize_output(&dumped_string, &[])
+            };
+
+            if self.config.bless {
+                let _ = std::fs::remove_file(&expected_file);
+                std::fs::write(expected_file, dumped_string.as_bytes()).unwrap();
+            } else {
+                if !expected_file.exists() {
+                    panic!("Output file `{}` from test does not exist", expected_file.display());
+                }
+                let expected_string = fs::read_to_string(&expected_file).unwrap();
+                if dumped_string != expected_string {
+                    print!("{}", write_diff(&expected_string, &dumped_string, 3));
+                    panic!(
+                        "Actual MIR output differs from expected MIR output {}",
                         expected_file.display()
                     );
-                    if !output_file.exists() {
-                        panic!(
-                            "Output file `{}` from test does not exist, available files are in `{}`",
-                            output_file.display(),
-                            output_file.parent().unwrap().display()
-                        );
-                    }
-                    self.check_mir_test_timestamp(&from_file, &output_file);
-                    let dumped_string = fs::read_to_string(&output_file).unwrap();
-                    self.normalize_output(&dumped_string, &[])
-                };
-
-                if self.config.bless {
-                    let _ = std::fs::remove_file(&expected_file);
-                    std::fs::write(expected_file, dumped_string.as_bytes()).unwrap();
-                } else {
-                    if !expected_file.exists() {
-                        panic!(
-                            "Output file `{}` from test does not exist",
-                            expected_file.display()
-                        );
-                    }
-                    let expected_string = fs::read_to_string(&expected_file).unwrap();
-                    if dumped_string != expected_string {
-                        print!("{}", write_diff(&expected_string, &dumped_string, 3));
-                        panic!(
-                            "Actual MIR output differs from expected MIR output {}",
-                            expected_file.display()
-                        );
-                    }
                 }
             }
         }
@@ -3948,3 +3879,8 @@ enum AllowUnused {
     Yes,
     No,
 }
+
+enum LinkToAux {
+    Yes,
+    No,
+}
diff --git a/src/tools/compiletest/src/util.rs b/src/tools/compiletest/src/util.rs
index e5ff0906be8a..ec36f1e4fb72 100644
--- a/src/tools/compiletest/src/util.rs
+++ b/src/tools/compiletest/src/util.rs
@@ -2,6 +2,7 @@ use crate::common::Config;
 use std::env;
 use std::ffi::OsStr;
 use std::path::PathBuf;
+use std::process::Command;
 
 use tracing::*;
 
@@ -111,3 +112,25 @@ impl PathBufExt for PathBuf {
         }
     }
 }
+
+/// The name of the environment variable that holds dynamic library locations.
+pub fn dylib_env_var() -> &'static str {
+    if cfg!(windows) {
+        "PATH"
+    } else if cfg!(target_os = "macos") {
+        "DYLD_LIBRARY_PATH"
+    } else if cfg!(target_os = "haiku") {
+        "LIBRARY_PATH"
+    } else {
+        "LD_LIBRARY_PATH"
+    }
+}
+
+/// Adds a list of lookup paths to `cmd`'s dynamic library lookup path.
+/// If the dylib_path_var is already set for this cmd, the old value will be overwritten!
+pub fn add_dylib_path(cmd: &mut Command, paths: impl Iterator<Item = impl Into<PathBuf>>) {
+    let path_env = env::var_os(dylib_env_var());
+    let old_paths = path_env.as_ref().map(env::split_paths);
+    let new_paths = paths.map(Into::into).chain(old_paths.into_iter().flatten());
+    cmd.env(dylib_env_var(), env::join_paths(new_paths).unwrap());
+}
diff --git a/src/tools/linkchecker/main.rs b/src/tools/linkchecker/main.rs
index 7842611bd4ff..4170c32f1fe2 100644
--- a/src/tools/linkchecker/main.rs
+++ b/src/tools/linkchecker/main.rs
@@ -55,30 +55,6 @@ const LINKCHECK_EXCEPTIONS: &[(&str, &[&str])] = &[
 
 #[rustfmt::skip]
 const INTRA_DOC_LINK_EXCEPTIONS: &[(&str, &[&str])] = &[
-    // This will never have links that are not in other pages.
-    // To avoid repeating the exceptions twice, an empty list means all broken links are allowed.
-    ("reference/print.html", &[]),
-    // All the reference 'links' are actually ENBF highlighted as code
-    ("reference/comments.html", &[
-         "/</code> <code>!",
-         "*</code> <code>!",
-    ]),
-    ("reference/identifiers.html", &[
-         "a</code>-<code>z</code> <code>A</code>-<code>Z",
-         "a</code>-<code>z</code> <code>A</code>-<code>Z</code> <code>0</code>-<code>9</code> <code>_",
-         "a</code>-<code>z</code> <code>A</code>-<code>Z</code>] [<code>a</code>-<code>z</code> <code>A</code>-<code>Z</code> <code>0</code>-<code>9</code> <code>_",
-    ]),
-    ("reference/tokens.html", &[
-         "0</code>-<code>1",
-         "0</code>-<code>7",
-         "0</code>-<code>9",
-         "0</code>-<code>9",
-         "0</code>-<code>9</code> <code>a</code>-<code>f</code> <code>A</code>-<code>F",
-    ]),
-    ("reference/notation.html", &[
-         "b</code> <code>B",
-         "a</code>-<code>z",
-    ]),
     // This is being used in the sense of 'inclusive range', not a markdown link
     ("core/ops/struct.RangeInclusive.html", &["begin</code>, <code>end"]),
     ("std/ops/struct.RangeInclusive.html", &["begin</code>, <code>end"]),
@@ -365,6 +341,33 @@ impl Checker {
             }
         });
 
+        self.check_intra_doc_links(file, &pretty_path, &source, report);
+
+        // we don't need the source anymore,
+        // so drop to reduce memory-usage
+        match self.cache.get_mut(&pretty_path).unwrap() {
+            FileEntry::HtmlFile { source, .. } => *source = Rc::new(String::new()),
+            _ => unreachable!("must be html file"),
+        }
+    }
+
+    fn check_intra_doc_links(
+        &mut self,
+        file: &Path,
+        pretty_path: &str,
+        source: &str,
+        report: &mut Report,
+    ) {
+        let relative = file.strip_prefix(&self.root).expect("should always be relative to root");
+        // Don't check the reference. It has several legitimate things that
+        // look like [<code>…</code>]. The reference has its own broken link
+        // checker in its CI which handles this using pulldown_cmark.
+        //
+        // This checks both the end of the root (when checking just the
+        // reference directory) or the beginning (when checking all docs).
+        if self.root.ends_with("reference") || relative.starts_with("reference") {
+            return;
+        }
         // Search for intra-doc links that rustdoc didn't warn about
         // FIXME(#77199, 77200) Rustdoc should just warn about these directly.
         // NOTE: only looks at one line at a time; in practice this should find most links
@@ -379,12 +382,6 @@ impl Checker {
                 }
             }
         }
-        // we don't need the source anymore,
-        // so drop to reduce memory-usage
-        match self.cache.get_mut(&pretty_path).unwrap() {
-            FileEntry::HtmlFile { source, .. } => *source = Rc::new(String::new()),
-            _ => unreachable!("must be html file"),
-        }
     }
 
     /// Load a file from disk, or from the cache if available.
diff --git a/src/tools/miri/.github/workflows/ci.yml b/src/tools/miri/.github/workflows/ci.yml
index 923f83913662..607ffe0cc59f 100644
--- a/src/tools/miri/.github/workflows/ci.yml
+++ b/src/tools/miri/.github/workflows/ci.yml
@@ -10,7 +10,7 @@ on:
     branches:
       - 'master'
   schedule:
-    - cron: '5 15 * * *' # At 15:05 UTC every day.
+    - cron: '6 6 * * *' # At 6:06 UTC every day.
 
 env:
   CARGO_UNSTABLE_SPARSE_REGISTRY: 'true'
@@ -22,17 +22,14 @@ jobs:
       RUST_BACKTRACE: 1
       HOST_TARGET: ${{ matrix.host_target }}
     strategy:
+      fail-fast: false
       matrix:
-        build: [linux64, macos, win32]
         include:
-          - build: linux64
-            os: ubuntu-latest
+          - os: ubuntu-latest
             host_target: x86_64-unknown-linux-gnu
-          - build: macos
-            os: macos-latest
+          - os: macos-latest
             host_target: x86_64-apple-darwin
-          - build: win32
-            os: windows-latest
+          - os: windows-latest
             host_target: i686-pc-windows-msvc
     steps:
       - uses: actions/checkout@v3
@@ -61,7 +58,7 @@ jobs:
           restore-keys: ${{ runner.os }}-cargo
 
       - name: Install rustup-toolchain-install-master
-        if: ${{ steps.cache-npm.outputs.cache-hit != 'true' }}
+        if: ${{ steps.cache.outputs.cache-hit != 'true' }}
         shell: bash
         run: |
           cargo install -f rustup-toolchain-install-master
@@ -70,9 +67,9 @@ jobs:
         shell: bash
         run: |
           if [[ ${{ github.event_name }} == 'schedule' ]]; then
-            ./rustup-toolchain HEAD --host ${{ matrix.host_target }}
+            ./miri toolchain HEAD --host ${{ matrix.host_target }}
           else
-            ./rustup-toolchain "" --host ${{ matrix.host_target }}
+            ./miri toolchain "" --host ${{ matrix.host_target }}
           fi
 
       - name: Show Rust version
@@ -89,11 +86,46 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3
-      - name: Install required toolchain
-        # We need a toolchain that can actually build Miri, just a nightly won't do.
+
+      # This is exactly duplicated from above. GHA is pretty terrible when it comes
+      # to avoiding code duplication.
+
+      # Cache the global cargo directory, but NOT the local `target` directory which
+      # we cannot reuse anyway when the nightly changes (and it grows quite large
+      # over time).
+      - name: Add cache for cargo
+        id: cache
+        uses: actions/cache@v3
+        with:
+          path: |
+            # Taken from <https://doc.rust-lang.org/nightly/cargo/guide/cargo-home.html#caching-the-cargo-home-in-ci>.
+            ~/.cargo/bin
+            ~/.cargo/registry/index
+            ~/.cargo/registry/cache
+            ~/.cargo/git/db
+            # contains package information of crates installed via `cargo install`.
+            ~/.cargo/.crates.toml
+            ~/.cargo/.crates2.json
+          key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}
+          restore-keys: ${{ runner.os }}-cargo
+
+      - name: Install rustup-toolchain-install-master
+        if: ${{ steps.cache.outputs.cache-hit != 'true' }}
+        shell: bash
         run: |
-          cargo install rustup-toolchain-install-master # TODO: cache this?
-          ./rustup-toolchain "" -c clippy
+          cargo install -f rustup-toolchain-install-master
+
+      - name: Install "master" toolchain
+        shell: bash
+        run: |
+          ./miri toolchain
+
+      - name: Show Rust version
+        run: |
+          rustup show
+          rustc -Vv
+          cargo -V
+
       - name: rustfmt
         run: ./miri fmt --check
       - name: clippy
diff --git a/src/tools/miri/.gitpod.yml b/src/tools/miri/.gitpod.yml
index 36bd991740a8..724cf26df2b9 100644
--- a/src/tools/miri/.gitpod.yml
+++ b/src/tools/miri/.gitpod.yml
@@ -4,6 +4,6 @@ tasks:
   - before: echo "..."
     init: |
       cargo install rustup-toolchain-install-master
-      ./rustup-toolchain
+      ./miri toolchain
       ./miri build
-    command: echo "Run tests with ./miri test"
\ No newline at end of file
+    command: echo "Run tests with ./miri test"
diff --git a/src/tools/miri/CONTRIBUTING.md b/src/tools/miri/CONTRIBUTING.md
index a88e69115ba3..5c41547616ec 100644
--- a/src/tools/miri/CONTRIBUTING.md
+++ b/src/tools/miri/CONTRIBUTING.md
@@ -23,13 +23,13 @@ tested against. Other versions will likely not work. After installing
 [`rustup-toolchain-install-master`], you can run the following command to
 install that exact version of rustc as a toolchain:
 ```
-./rustup-toolchain
+./miri toolchain
 ```
 This will set up a rustup toolchain called `miri` and set it as an override for
 the current directory.
 
 You can also create a `.auto-everything` file (contents don't matter, can be empty), which
-will cause any `./miri` command to automatically call `rustup-toolchain`, `clippy` and `rustfmt`
+will cause any `./miri` command to automatically call `./miri toolchain`, `clippy` and `rustfmt`
 for you. If you don't want all of these to happen, you can add individual `.auto-toolchain`,
 `.auto-clippy` and `.auto-fmt` files respectively.
 
@@ -104,7 +104,7 @@ MIRI_LOG=rustc_mir::interpret=info,miri::stacked_borrows ./miri run tests/pass/v
 In addition, you can set `MIRI_BACKTRACE=1` to get a backtrace of where an
 evaluation error was originally raised.
 
-#### UI testing
+### UI testing
 
 We use ui-testing in Miri, meaning we generate `.stderr` and `.stdout` files for the output
 produced by Miri. You can use `./miri bless` to automatically (re)generate these files when
@@ -132,12 +132,15 @@ development version of Miri using
 and then you can use it as if it was installed by `rustup`.  Make sure you use
 the same toolchain when calling `cargo miri` that you used when installing Miri!
 Usually this means you have to write `cargo +miri miri ...` to select the `miri`
-toolchain that was installed by `./rustup-toolchain`.
+toolchain that was installed by `./miri toolchain`.
 
 There's a test for the cargo wrapper in the `test-cargo-miri` directory; run
 `./run-test.py` in there to execute it. Like `./miri test`, this respects the
 `MIRI_TEST_TARGET` environment variable to execute the test for another target.
 
+Note that installing Miri like this will "take away" Miri management from `rustup`.
+If you want to later go back to a rustup-installed Miri, run `rustup update`.
+
 ### Using a modified standard library
 
 Miri re-builds the standard library into a custom sysroot, so it is fairly easy
@@ -214,7 +217,7 @@ for changes in rustc. In both cases, `rustc-version` needs updating.
 
 To update the `rustc-version` file and install the latest rustc, you can run:
 ```
-./rustup-toolchain HEAD
+./miri toolchain HEAD
 ```
 
 Now edit Miri until `./miri test` passes, and submit a PR. Generally, it is
@@ -257,7 +260,7 @@ Note: When you are working with a locally built rustc or any other toolchain tha
 is not the same as the one in `rust-version`, you should not have `.auto-everything` or
 `.auto-toolchain` as that will keep resetting your toolchain.
 
-```
+```sh
 rm -f .auto-everything .auto-toolchain
 ```
 
@@ -275,3 +278,48 @@ see <https://rustc-dev-guide.rust-lang.org/building/how-to-build-and-run.html>.
 
 With this, you should now have a working development setup! See
 [above](#building-and-testing-miri) for how to proceed working on Miri.
+
+## Advanced topic: Syncing with the rustc repo
+
+We use the [`josh` proxy](https://github.com/josh-project/josh) to transmit
+changes between the rustc and Miri repositories. For now, a fork of josh needs to be built
+from source. This downloads and runs josh:
+
+```sh
+git clone https://github.com/RalfJung/josh
+cd josh
+cargo run --release -p josh-proxy -- --local=$(pwd)/local --remote=https://github.com --no-background
+```
+
+### Importing changes from the rustc repo
+
+Josh needs to be running, as described above.
+We assume we start on an up-to-date master branch in the Miri repo.
+
+```sh
+# Fetch and merge rustc side of the history. Takes ca 5 min the first time.
+./miri rustc-pull
+# Update toolchain reference and apply formatting.
+./miri toolchain HEAD && ./miri fmt
+git commit -am "rustup"
+```
+
+Now push this to a new branch in your Miri fork, and create a PR. It is worth
+running `./miri test` locally in parallel, since the test suite in the Miri repo
+is stricter than the one on the rustc side, so some small tweaks might be
+needed.
+
+### Exporting changes to the rustc repo
+
+Josh needs to be running, as described above. We will use the josh proxy to push
+to your fork of rustc. Run the following in the Miri repo, assuming we are on an
+up-to-date master branch:
+
+```sh
+# Push the Miri changes to your rustc fork (substitute your github handle for YOUR_NAME).
+./miri rustc-push YOUR_NAME miri
+```
+
+This will create a new branch called 'miri' in your fork, and the output should
+include a link to create a rustc PR that will integrate those changes into the
+main repository.
diff --git a/src/tools/miri/Cargo.lock b/src/tools/miri/Cargo.lock
index 5a4bb6544947..343cf0eaba25 100644
--- a/src/tools/miri/Cargo.lock
+++ b/src/tools/miri/Cargo.lock
@@ -320,9 +320,9 @@ dependencies = [
 
 [[package]]
 name = "libffi-sys"
-version = "2.0.0"
+version = "2.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ab4106b7f09d7b87d021334d5618fac1dfcfb824d4c5fe111ff0074dfd242e15"
+checksum = "84e78d02e5a8eae9c24c38ce6e6026f80e16dff76adcdae4bc5c6c52c2de4a60"
 dependencies = [
  "cc",
 ]
@@ -419,6 +419,7 @@ dependencies = [
  "rand",
  "regex",
  "rustc-workspace-hack",
+ "rustc_version",
  "shell-escape",
  "smallvec",
  "ui_test",
diff --git a/src/tools/miri/Cargo.toml b/src/tools/miri/Cargo.toml
index 0c547d585d19..02485dab74c5 100644
--- a/src/tools/miri/Cargo.toml
+++ b/src/tools/miri/Cargo.toml
@@ -31,14 +31,17 @@ smallvec = "1.7"
 rustc-workspace-hack = "1.0.0"
 measureme = "10.0.0"
 
-[target."cfg(unix)".dependencies]
+[target.'cfg(unix)'.dependencies]
 libc = "0.2"
+
+[target.'cfg(target_os = "linux")'.dependencies]
 libffi = "3.0.0"
 libloading = "0.7"
 
 [dev-dependencies]
 colored = "2"
 ui_test = "0.3.1"
+rustc_version = "0.4"
 # Features chosen to match those required by env_logger, to avoid rebuilds
 regex = { version = "1.5.5", default-features = false, features = ["perf", "std"] }
 lazy_static = "1.4.0"
diff --git a/src/tools/miri/README.md b/src/tools/miri/README.md
index d75f0cc1e80d..1185525f6865 100644
--- a/src/tools/miri/README.md
+++ b/src/tools/miri/README.md
@@ -374,9 +374,15 @@ to Miri failing to detect cases of undefined behavior in a program.
   application instead of raising an error within the context of Miri (and halting
   execution). Note that code might not expect these operations to ever panic, so
   this flag can lead to strange (mis)behavior.
-* `-Zmiri-retag-fields` changes Stacked Borrows retagging to recurse into fields.
+* `-Zmiri-retag-fields` changes Stacked Borrows retagging to recurse into *all* fields.
   This means that references in fields of structs/enums/tuples/arrays/... are retagged,
   and in particular, they are protected when passed as function arguments.
+  (The default is to recurse only in cases where rustc would actually emit a `noalias` attribute.)
+* `-Zmiri-retag-fields=<all|none|scalar>` controls when Stacked Borrows retagging recurses into
+  fields. `all` means it always recurses (like `-Zmiri-retag-fields`), `none` means it never
+  recurses, `scalar` (the default) means it only recurses for types where we would also emit
+  `noalias` annotations in the generated LLVM IR (types passed as indivudal scalars or pairs of
+  scalars). Setting this to `none` is **unsound**.
 * `-Zmiri-tag-gc=<blocks>` configures how often the pointer tag garbage collector runs. The default
   is to search for and remove unreachable tags once every `10000` basic blocks. Setting this to
   `0` disables the garbage collector, which causes some programs to have explosive memory usage
@@ -414,9 +420,9 @@ Some native rustc `-Z` flags are also very relevant for Miri:
 
 Moreover, Miri recognizes some environment variables:
 
-* `MIRI_AUTO_OPS` indicates whether the automatic execution of rustfmt, clippy and rustup-toolchain
-  should be skipped. If it is set to any value, they are skipped. This is used for avoiding
-  infinite recursion in `./miri` and to allow automated IDE actions to avoid the auto ops.
+* `MIRI_AUTO_OPS` indicates whether the automatic execution of rustfmt, clippy and toolchain setup
+  should be skipped. If it is set to any value, they are skipped. This is used for avoiding infinite
+  recursion in `./miri` and to allow automated IDE actions to avoid the auto ops.
 * `MIRI_LOG`, `MIRI_BACKTRACE` control logging and backtrace printing during
   Miri executions, also [see "Testing the Miri driver" in `CONTRIBUTING.md`][testing-miri].
 * `MIRIFLAGS` (recognized by `cargo miri` and the test suite) defines extra
@@ -428,18 +434,19 @@ Moreover, Miri recognizes some environment variables:
   trigger a re-build of the standard library; you have to clear the Miri build
   cache manually (on Linux, `rm -rf ~/.cache/miri`).
 * `MIRI_SYSROOT` (recognized by `cargo miri` and the Miri driver) indicates the sysroot to use. When
-  using `cargo miri`, only set this if you do not want to use the automatically created sysroot. For
-  directly invoking the Miri driver, this variable (or a `--sysroot` flag) is mandatory.
+  using `cargo miri`, this skips the automatic setup -- only set this if you do not want to use the
+  automatically created sysroot. For directly invoking the Miri driver, this variable (or a
+  `--sysroot` flag) is mandatory. When invoking `cargo miri setup`, this indicates where the sysroot
+  will be put.
 * `MIRI_TEST_TARGET` (recognized by the test suite and the `./miri` script) indicates which target
   architecture to test against.  `miri` and `cargo miri` accept the `--target` flag for the same
   purpose.
 * `MIRI_NO_STD` (recognized by `cargo miri` and the test suite) makes sure that the target's
   sysroot is built without libstd. This allows testing and running no_std programs.
-* `MIRI_BLESS` (recognized by the test suite) overwrite all `stderr` and `stdout` files
-  instead of checking whether the output matches.
-* `MIRI_SKIP_UI_CHECKS` (recognized by the test suite) don't check whether the
-  `stderr` or `stdout` files match the actual output. Useful for the rustc test suite
-  which has subtle differences that we don't care about.
+* `MIRI_BLESS` (recognized by the test suite and `cargo-miri-test/run-test.py`): overwrite all
+  `stderr` and `stdout` files instead of checking whether the output matches.
+* `MIRI_SKIP_UI_CHECKS` (recognized by the test suite): don't check whether the
+  `stderr` or `stdout` files match the actual output.
 
 The following environment variables are *internal* and must not be used by
 anyone but Miri itself. They are used to communicate between different Miri
@@ -532,6 +539,35 @@ extern "Rust" {
     /// This is internal and unstable and should not be used; we give it here
     /// just to be complete.
     fn miri_start_panic(payload: *mut u8) -> !;
+
+    /// Miri-provided extern function to get the internal unique identifier for the allocation that a pointer
+    /// points to. If this pointer is invalid (not pointing to an allocation), interpretation will abort.
+    ///
+    /// This is only useful as an input to `miri_print_borrow_stacks`, and it is a separate call because
+    /// getting a pointer to an allocation at runtime can change the borrow stacks in the allocation.
+    /// This function should be considered unstable. It exists only to support `miri_print_borrow_stacks` and so
+    /// inherits all of its instability.
+    fn miri_get_alloc_id(ptr: *const ()) -> u64;
+
+    /// Miri-provided extern function to print (from the interpreter, not the program) the contents of all
+    /// borrow stacks in an allocation. The leftmost tag is the bottom of the stack.
+    /// The format of what this emits is unstable and may change at any time. In particular, users should be
+    /// aware that Miri will periodically attempt to garbage collect the contents of all stacks. Callers of
+    /// this function may wish to pass `-Zmiri-tag-gc=0` to disable the GC.
+    ///
+    /// This function is extremely unstable. At any time the format of its output may change, its signature may
+    /// change, or it may be removed entirely.
+    fn miri_print_borrow_stacks(alloc_id: u64);
+
+    /// Miri-provided extern function to print (from the interpreter, not the
+    /// program) the contents of a section of program memory, as bytes. Bytes
+    /// written using this function will emerge from the interpreter's stdout.
+    fn miri_write_to_stdout(bytes: &[u8]);
+
+    /// Miri-provided extern function to print (from the interpreter, not the
+    /// program) the contents of a section of program memory, as bytes. Bytes
+    /// written using this function will emerge from the interpreter's stderr.
+    fn miri_write_to_stderr(bytes: &[u8]);
 }
 ```
 
diff --git a/src/tools/miri/bench-cargo-miri/serde2/src/main.rs b/src/tools/miri/bench-cargo-miri/serde2/src/main.rs
index c81b32c13fef..83c04b9dd5f5 100644
--- a/src/tools/miri/bench-cargo-miri/serde2/src/main.rs
+++ b/src/tools/miri/bench-cargo-miri/serde2/src/main.rs
@@ -5,6 +5,7 @@ use serde::Deserialize;
 use std::thread;
 
 #[derive(Deserialize)]
+#[allow(unused)]
 struct DeriveStruct {
     buffer: Vec<i16>,
 }
diff --git a/src/tools/miri/build.rs b/src/tools/miri/build.rs
index 37c626baab58..0977c0ba016b 100644
--- a/src/tools/miri/build.rs
+++ b/src/tools/miri/build.rs
@@ -4,5 +4,5 @@ fn main() {
     // Re-export the TARGET environment variable so it can
     // be accessed by miri.
     let target = std::env::var("TARGET").unwrap();
-    println!("cargo:rustc-env=TARGET={}", target);
+    println!("cargo:rustc-env=TARGET={target}");
 }
diff --git a/src/tools/miri/cargo-miri/src/phases.rs b/src/tools/miri/cargo-miri/src/phases.rs
index 0c1f039d6cc0..df36041c75ed 100644
--- a/src/tools/miri/cargo-miri/src/phases.rs
+++ b/src/tools/miri/cargo-miri/src/phases.rs
@@ -34,7 +34,7 @@ Examples:
 "#;
 
 fn show_help() {
-    println!("{}", CARGO_MIRI_HELP);
+    println!("{CARGO_MIRI_HELP}");
 }
 
 fn show_version() {
@@ -52,7 +52,7 @@ fn forward_patched_extern_arg(args: &mut impl Iterator<Item = String>, cmd: &mut
     let path = args.next().expect("`--extern` should be followed by a filename");
     if let Some(lib) = path.strip_suffix(".rlib") {
         // If this is an rlib, make it an rmeta.
-        cmd.arg(format!("{}.rmeta", lib));
+        cmd.arg(format!("{lib}.rmeta"));
     } else {
         // Some other extern file (e.g. a `.so`). Forward unchanged.
         cmd.arg(path);
@@ -336,7 +336,7 @@ pub fn phase_rustc(mut args: impl Iterator<Item = String>, phase: RustcPhase) {
                     "[cargo-miri rustc inside rustdoc] captured input:\n{}",
                     std::str::from_utf8(&env.stdin).unwrap()
                 );
-                eprintln!("[cargo-miri rustc inside rustdoc] going to run:\n{:?}", cmd);
+                eprintln!("[cargo-miri rustc inside rustdoc] going to run:\n{cmd:?}");
             }
 
             exec_with_pipe(cmd, &env.stdin, format!("{}.stdin", out_filename("", "").display()));
@@ -374,7 +374,7 @@ pub fn phase_rustc(mut args: impl Iterator<Item = String>, phase: RustcPhase) {
                         val.push("metadata");
                     }
                 }
-                cmd.arg(format!("{}={}", emit_flag, val.join(",")));
+                cmd.arg(format!("{emit_flag}={}", val.join(",")));
             } else if arg == "--extern" {
                 // Patch `--extern` filenames, since Cargo sometimes passes stub `.rlib` files:
                 // https://github.com/rust-lang/miri/issues/1705
@@ -528,14 +528,14 @@ pub fn phase_runner(mut binary_args: impl Iterator<Item = String>, phase: Runner
     cmd.args(binary_args);
 
     // Make sure we use the build-time working directory for interpreting Miri/rustc arguments.
-    // But then we need to switch to the run-time one, which we instruct Miri do do by setting `MIRI_CWD`.
+    // But then we need to switch to the run-time one, which we instruct Miri to do by setting `MIRI_CWD`.
     cmd.current_dir(info.current_dir);
     cmd.env("MIRI_CWD", env::current_dir().unwrap());
 
     // Run it.
     debug_cmd("[cargo-miri runner]", verbose, &cmd);
     match phase {
-        RunnerPhase::Rustdoc => exec_with_pipe(cmd, &info.stdin, format!("{}.stdin", binary)),
+        RunnerPhase::Rustdoc => exec_with_pipe(cmd, &info.stdin, format!("{binary}.stdin")),
         RunnerPhase::Cargo => exec(cmd),
     }
 }
diff --git a/src/tools/miri/cargo-miri/src/setup.rs b/src/tools/miri/cargo-miri/src/setup.rs
index 72d8ef2f7522..f3841a614083 100644
--- a/src/tools/miri/cargo-miri/src/setup.rs
+++ b/src/tools/miri/cargo-miri/src/setup.rs
@@ -17,10 +17,8 @@ pub fn setup(subcommand: &MiriCommand, target: &str, rustc_version: &VersionMeta
     let only_setup = matches!(subcommand, MiriCommand::Setup);
     let ask_user = !only_setup;
     let print_sysroot = only_setup && has_arg_flag("--print-sysroot"); // whether we just print the sysroot path
-    if std::env::var_os("MIRI_SYSROOT").is_some() {
-        if only_setup {
-            println!("WARNING: MIRI_SYSROOT already set, not doing anything.")
-        }
+    if !only_setup && std::env::var_os("MIRI_SYSROOT").is_some() {
+        // Skip setup step if MIRI_SYSROOT is explicitly set, *unless* we are `cargo miri setup`.
         return;
     }
 
@@ -61,8 +59,13 @@ pub fn setup(subcommand: &MiriCommand, target: &str, rustc_version: &VersionMeta
     }
 
     // Determine where to put the sysroot.
-    let user_dirs = directories::ProjectDirs::from("org", "rust-lang", "miri").unwrap();
-    let sysroot_dir = user_dirs.cache_dir();
+    let sysroot_dir = match std::env::var_os("MIRI_SYSROOT") {
+        Some(dir) => PathBuf::from(dir),
+        None => {
+            let user_dirs = directories::ProjectDirs::from("org", "rust-lang", "miri").unwrap();
+            user_dirs.cache_dir().to_owned()
+        }
+    };
     // Sysroot configuration and build details.
     let sysroot_config = if std::env::var_os("MIRI_NO_STD").is_some() {
         SysrootConfig::NoStd
@@ -111,7 +114,7 @@ pub fn setup(subcommand: &MiriCommand, target: &str, rustc_version: &VersionMeta
         (command, rustflags)
     };
     // Make sure all target-level Miri invocations know their sysroot.
-    std::env::set_var("MIRI_SYSROOT", sysroot_dir);
+    std::env::set_var("MIRI_SYSROOT", &sysroot_dir);
 
     // Do the build.
     if only_setup {
@@ -121,7 +124,7 @@ pub fn setup(subcommand: &MiriCommand, target: &str, rustc_version: &VersionMeta
         // We want to be quiet, but still let the user know that something is happening.
         eprint!("Preparing a sysroot for Miri (target: {target})... ");
     }
-    Sysroot::new(sysroot_dir, target)
+    Sysroot::new(&sysroot_dir, target)
         .build_from_source(&rust_src, BuildMode::Check, sysroot_config, rustc_version, cargo_cmd)
         .unwrap_or_else(|_| {
             if only_setup {
diff --git a/src/tools/miri/cargo-miri/src/util.rs b/src/tools/miri/cargo-miri/src/util.rs
index aabe5547e5c9..60f39cb36aba 100644
--- a/src/tools/miri/cargo-miri/src/util.rs
+++ b/src/tools/miri/cargo-miri/src/util.rs
@@ -83,7 +83,7 @@ pub fn escape_for_toml(s: &str) -> String {
     // We want to surround this string in quotes `"`. So we first escape all quotes,
     // and also all backslashes (that are used to escape quotes).
     let s = s.replace('\\', r#"\\"#).replace('"', r#"\""#);
-    format!("\"{}\"", s)
+    format!("\"{s}\"")
 }
 
 /// Returns the path to the `miri` binary
@@ -175,7 +175,7 @@ pub fn ask_to_run(mut cmd: Command, ask: bool, text: &str) {
     let is_ci = env::var_os("CI").is_some() || env::var_os("TF_BUILD").is_some();
     if ask && !is_ci {
         let mut buf = String::new();
-        print!("I will run `{:?}` to {}. Proceed? [Y/n] ", cmd, text);
+        print!("I will run `{cmd:?}` to {text}. Proceed? [Y/n] ");
         io::stdout().flush().unwrap();
         io::stdin().read_line(&mut buf).unwrap();
         match buf.trim().to_lowercase().as_ref() {
@@ -185,10 +185,10 @@ pub fn ask_to_run(mut cmd: Command, ask: bool, text: &str) {
             a => show_error!("invalid answer `{}`", a),
         };
     } else {
-        eprintln!("Running `{:?}` to {}.", cmd, text);
+        eprintln!("Running `{cmd:?}` to {text}.");
     }
 
-    if cmd.status().unwrap_or_else(|_| panic!("failed to execute {:?}", cmd)).success().not() {
+    if cmd.status().unwrap_or_else(|_| panic!("failed to execute {cmd:?}")).success().not() {
         show_error!("failed to {}", text);
     }
 }
@@ -276,12 +276,12 @@ pub fn debug_cmd(prefix: &str, verbose: usize, cmd: &Command) {
         // Print only what has been changed for this `cmd`.
         for (var, val) in cmd.get_envs() {
             if let Some(val) = val {
-                writeln!(out, "{}={:?} \\", var.to_string_lossy(), val).unwrap();
+                writeln!(out, "{}={val:?} \\", var.to_string_lossy()).unwrap();
             } else {
                 writeln!(out, "--unset={}", var.to_string_lossy()).unwrap();
             }
         }
     }
     write!(out, "{cmd:?}").unwrap();
-    eprintln!("{}", out);
+    eprintln!("{out}");
 }
diff --git a/src/tools/miri/ci.sh b/src/tools/miri/ci.sh
index aa322e54a31d..72b7b791a47e 100755
--- a/src/tools/miri/ci.sh
+++ b/src/tools/miri/ci.sh
@@ -93,6 +93,7 @@ case $HOST_TARGET in
     ;;
   i686-pc-windows-msvc)
     MIRI_TEST_TARGET=x86_64-unknown-linux-gnu run_tests
+    MIRI_TEST_TARGET=x86_64-pc-windows-gnu run_tests
     ;;
   *)
     echo "FATAL: unknown OS"
diff --git a/src/tools/miri/miri b/src/tools/miri/miri
index e492308a62eb..f0986bfb1cdb 100755
--- a/src/tools/miri/miri
+++ b/src/tools/miri/miri
@@ -42,6 +42,22 @@ many different seeds.
 Runs the benchmarks from bench-cargo-miri in hyperfine. hyperfine needs to be installed.
 <benches> can explicitly list the benchmarks to run; by default, all of them are run.
 
+./miri rustc-pull:
+Pull and merge Miri changes from the rustc repo.
+
+./miri rustc-push <github user> <branch>:
+Push Miri changes back to the rustc repo. This will update the 'master' branch
+in the Rust fork of the given user to upstream. It will also pull a copy of the
+rustc history into the Miri repo, unless you set the RUSTC_GIT env var to an
+existing clone of the rustc repo.
+
+./miri toolchain <commit> <flags>:
+Update and activate the rustup toolchain 'miri'. If no commit is given, updates
+to the commit given in the `rust-version` file. If the commit is `HEAD`, updates
+to the latest upstream rustc commit.
+`rustup-toolchain-install-master` must be installed for this to work. Any extra
+flags are passed to `rustup-toolchain-install-master`.
+
   ENVIRONMENT VARIABLES
 
 MIRI_SYSROOT:
@@ -52,37 +68,98 @@ Pass extra flags to all cargo invocations. (Ignored by `./miri cargo`.)
 EOF
 )
 
-## We need to know where we are.
+## We need to know which command to run and some global constants.
+COMMAND="$1"
+if [ -z "$COMMAND" ]; then
+    echo "$USAGE"
+    exit 1
+fi
+shift
 # macOS does not have a useful readlink/realpath so we have to use Python instead...
 MIRIDIR=$(python3 -c 'import os, sys; print(os.path.dirname(os.path.realpath(sys.argv[1])))' "$0")
-
-## Run the auto-things.
-if [ -z "$MIRI_AUTO_OPS" ]; then
-    export MIRI_AUTO_OPS=42
-
-    # Run this first, so that the toolchain doesn't change after
-    # other code has run.
-    if [ -f "$MIRIDIR/.auto-everything" ] || [ -f "$MIRIDIR/.auto-toolchain" ] ; then
-        (cd "$MIRIDIR" && ./rustup-toolchain)
-    fi
-
-    if [ -f "$MIRIDIR/.auto-everything" ] || [ -f "$MIRIDIR/.auto-fmt" ] ; then
-        $0 fmt
-    fi
-
-    if [ -f "$MIRIDIR/.auto-everything" ] || [ -f "$MIRIDIR/.auto-clippy" ] ; then
-        $0 clippy -- -D warnings
-    fi
-fi
-
-## Determine command and toolchain.
-COMMAND="$1"
-[ $# -gt 0 ] && shift
-# Doing this *after* auto-toolchain logic above, since that might change the toolchain.
+# Used for rustc syncs.
+JOSH_FILTER=":at_commit=75dd959a3a40eb5b4574f8d2e23aa6efbeb33573[:prefix=src/tools/miri]:/src/tools/miri"
+# Needed for `./miri bench`.
 TOOLCHAIN=$(cd "$MIRIDIR"; rustup show active-toolchain | head -n 1 | cut -d ' ' -f 1)
 
-## Handle some commands early, since they should *not* alter the environment.
+## Early commands, that don't do auto-things and don't want the environment-altering things happening below.
 case "$COMMAND" in
+toolchain)
+    cd "$MIRIDIR"
+    # Make sure rustup-toolchain-install-master is installed.
+    if ! which rustup-toolchain-install-master >/dev/null; then
+        echo "Please install rustup-toolchain-install-master by running 'cargo install rustup-toolchain-install-master'"
+        exit 1
+    fi
+    # Determine new commit.
+    if [[ "$1" == "" ]]; then
+        NEW_COMMIT=$(cat rust-version)
+    elif [[ "$1" == "HEAD" ]]; then
+        NEW_COMMIT=$(git ls-remote https://github.com/rust-lang/rust/ HEAD | cut -f 1)
+    else
+        NEW_COMMIT="$1"
+    fi
+    echo "$NEW_COMMIT" > rust-version
+    shift || true # don't fail if shifting fails because no commit was given
+    # Check if we already are at that commit.
+    CUR_COMMIT=$(rustc +miri --version -v 2>/dev/null | grep "^commit-hash: " | cut -d " " -f 2)
+    if [[ "$CUR_COMMIT" == "$NEW_COMMIT" ]]; then
+        echo "miri toolchain is already at commit $CUR_COMMIT."
+        rustup override set miri
+        exit 0
+    fi
+    # Install and setup new toolchain.
+    rustup toolchain uninstall miri
+    rustup-toolchain-install-master -n miri -c cargo -c rust-src -c rustc-dev -c llvm-tools -c rustfmt -c clippy "$@" -- "$NEW_COMMIT"
+    rustup override set miri
+    # Cleanup.
+    cargo clean
+    # Call 'cargo metadata' on the sources in case that changes the lockfile
+    # (which fails under some setups when it is done from inside vscode).
+    cargo metadata --format-version 1 --manifest-path "$(rustc --print sysroot)/lib/rustlib/rustc-src/rust/compiler/rustc/Cargo.toml" >/dev/null
+    # Done!
+    exit 0
+    ;;
+rustc-pull)
+    cd "$MIRIDIR"
+    git fetch http://localhost:8000/rust-lang/rust.git$JOSH_FILTER.git master
+    git merge FETCH_HEAD --no-ff -m "Merge from rustc"
+    exit 0
+    ;;
+rustc-push)
+    USER="$1"
+    BRANCH="$2"
+    if [ -z "$USER" ] || [ -z "$BRANCH" ]; then
+        echo "Usage: $0 rustc-push <github user> <branch>"
+        exit 1
+    fi
+    if [ -n "$RUSTC_GIT" ]; then
+        # Use an existing fork for the branch updates.
+        cd "$RUSTC_GIT"
+    else
+        # Do this in the local Miri repo.
+        echo "This will pull a copy of the rust-lang/rust history into this Miri checkout, growing it by about 1GB."
+        read -r -p "To avoid that, abort now and set the RUSTC_GIT environment variable to an existing rustc checkout. Proceed? [y/N] "
+        if [[ ! $REPLY =~ ^[Yy]$ ]]; then
+            exit 1
+        fi
+        cd "$MIRIDIR"
+    fi
+    # Prepare the branches. For reliable pushing we need to push to a non-existent branch
+    # and set `-o base` to a branch that holds current rustc master.
+    echo "Preparing $USER/rust..."
+    if git fetch https://github.com/$USER/rust $BRANCH &>/dev/null; then
+        echo "The '$BRANCH' seems to already exist in $USER/rust. Please delete it and try again."
+        exit 1
+    fi
+    git fetch https://github.com/rust-lang/rust master
+    git push https://github.com/$USER/rust FETCH_HEAD:master
+    # Do the actual push.
+    cd "$MIRIDIR"
+    echo "Pushing Miri changes..."
+    git push http://localhost:8000/$USER/rust.git$JOSH_FILTER.git HEAD:$BRANCH -o base=master
+    exit 0
+    ;;
 many-seeds)
     for SEED in $({ echo obase=16; seq 0 255; } | bc); do
         echo "Trying seed: $SEED"
@@ -106,9 +183,29 @@ bench)
     ;;
 esac
 
+## Run the auto-things.
+if [ -z "$MIRI_AUTO_OPS" ]; then
+    export MIRI_AUTO_OPS=42
+
+    # Run this first, so that the toolchain doesn't change after
+    # other code has run.
+    if [ -f "$MIRIDIR/.auto-everything" ] || [ -f "$MIRIDIR/.auto-toolchain" ] ; then
+        $0 toolchain
+        # Let's make sure to actually use that toolchain, too.
+        TOOLCHAIN=miri
+    fi
+
+    if [ -f "$MIRIDIR/.auto-everything" ] || [ -f "$MIRIDIR/.auto-fmt" ] ; then
+        $0 fmt
+    fi
+
+    if [ -f "$MIRIDIR/.auto-everything" ] || [ -f "$MIRIDIR/.auto-clippy" ] ; then
+        $0 clippy -- -D warnings
+    fi
+fi
+
 ## Prepare the environment
 # Determine some toolchain properties
-# export the target so its available in miri
 TARGET=$(rustc +$TOOLCHAIN --version --verbose | grep "^host:" | cut -d ' ' -f 2)
 SYSROOT=$(rustc +$TOOLCHAIN --print sysroot)
 LIBDIR=$SYSROOT/lib/rustlib/$TARGET/lib
@@ -227,10 +324,7 @@ cargo)
     $CARGO "$@"
     ;;
 *)
-    if [ -n "$COMMAND" ]; then
-      echo "Unknown command: $COMMAND"
-      echo
-    fi
-    echo "$USAGE"
+    echo "Unknown command: $COMMAND"
     exit 1
+    ;;
 esac
diff --git a/src/tools/miri/rust-version b/src/tools/miri/rust-version
index 78b9a110aa7c..13492d183c99 100644
--- a/src/tools/miri/rust-version
+++ b/src/tools/miri/rust-version
@@ -1 +1 @@
-acb8934fd57b3c2740c4abac0a5728c2c9b1423b
+b03502b35d111bef0399a66ab3cc765f0802e8ba
diff --git a/src/tools/miri/rustup-toolchain b/src/tools/miri/rustup-toolchain
deleted file mode 100755
index d7730f2b06d3..000000000000
--- a/src/tools/miri/rustup-toolchain
+++ /dev/null
@@ -1,53 +0,0 @@
-#!/bin/bash
-set -e
-# Manages a rustup toolchain called "miri".
-#
-# All commands set "miri" as the override toolchain for the current directory,
-# and make the `rust-version` file match that toolchain.
-#
-# USAGE:
-#
-# ./rustup-toolchain: Update "miri" toolchain to match `rust-version` (the known-good version for this commit).
-#
-# ./rustup-toolchain HEAD: Update "miri" toolchain and `rust-version` file to latest rustc HEAD.
-#
-# ./rustup-toolchain $COMMIT: Update "miri" toolchain and `rust-version` file to match that commit.
-#
-# Any extra parameters are passed to `rustup-toolchain-install-master`.
-
-# Make sure rustup-toolchain-install-master is installed.
-if ! which rustup-toolchain-install-master >/dev/null; then
-    echo "Please install rustup-toolchain-install-master by running 'cargo install rustup-toolchain-install-master'"
-    exit 1
-fi
-
-# Determine new commit.
-if [[ "$1" == "" ]]; then
-    NEW_COMMIT=$(cat rust-version)
-elif [[ "$1" == "HEAD" ]]; then
-    NEW_COMMIT=$(git ls-remote https://github.com/rust-lang/rust/ HEAD | cut -f 1)
-else
-    NEW_COMMIT="$1"
-fi
-echo "$NEW_COMMIT" > rust-version
-shift || true # don't fail if shifting fails
-
-# Check if we already are at that commit.
-CUR_COMMIT=$(rustc +miri --version -v 2>/dev/null | grep "^commit-hash: " | cut -d " " -f 2)
-if [[ "$CUR_COMMIT" == "$NEW_COMMIT" ]]; then
-    echo "miri toolchain is already at commit $CUR_COMMIT."
-    rustup override set miri
-    exit 0
-fi
-
-# Install and setup new toolchain.
-rustup toolchain uninstall miri
-rustup-toolchain-install-master -n miri -c cargo -c rust-src -c rustc-dev -c llvm-tools -c rustfmt -c clippy "$@" -- "$NEW_COMMIT"
-rustup override set miri
-
-# Cleanup.
-cargo clean
-
-# Call 'cargo metadata' on the sources in case that changes the lockfile
-# (which fails under some setups when it is done from inside vscode).
-cargo metadata --format-version 1 --manifest-path "$(rustc --print sysroot)/lib/rustlib/rustc-src/rust/compiler/rustc/Cargo.toml" >/dev/null
diff --git a/src/tools/miri/src/bin/miri.rs b/src/tools/miri/src/bin/miri.rs
index 5b16fc2948cb..e673ea67dbc5 100644
--- a/src/tools/miri/src/bin/miri.rs
+++ b/src/tools/miri/src/bin/miri.rs
@@ -32,7 +32,7 @@ use rustc_middle::{
 };
 use rustc_session::{config::CrateType, search_paths::PathKind, CtfeBacktrace};
 
-use miri::{BacktraceStyle, ProvenanceMode};
+use miri::{BacktraceStyle, ProvenanceMode, RetagFields};
 
 struct MiriCompilerCalls {
     miri_config: miri::MiriConfig,
@@ -192,7 +192,7 @@ fn init_late_loggers(tcx: TyCtxt<'_>) {
             if log::Level::from_str(&var).is_ok() {
                 env::set_var(
                     "RUSTC_LOG",
-                    &format!(
+                    format!(
                         "rustc_middle::mir::interpret={0},rustc_const_eval::interpret={0}",
                         var
                     ),
@@ -216,76 +216,28 @@ fn init_late_loggers(tcx: TyCtxt<'_>) {
     }
 }
 
-/// Returns the "default sysroot" that Miri will use for host things if no `--sysroot` flag is set.
-/// Should be a compile-time constant.
-fn host_sysroot() -> Option<String> {
-    if option_env!("RUSTC_STAGE").is_some() {
-        // This is being built as part of rustc, and gets shipped with rustup.
-        // We can rely on the sysroot computation in librustc_session.
-        return None;
-    }
-    // For builds outside rustc, we need to ensure that we got a sysroot
-    // that gets used as a default.  The sysroot computation in librustc_session would
-    // end up somewhere in the build dir (see `get_or_default_sysroot`).
-    // Taken from PR <https://github.com/Manishearth/rust-clippy/pull/911>.
-    let home = option_env!("RUSTUP_HOME").or(option_env!("MULTIRUST_HOME"));
-    let toolchain = option_env!("RUSTUP_TOOLCHAIN").or(option_env!("MULTIRUST_TOOLCHAIN"));
-    Some(match (home, toolchain) {
-        (Some(home), Some(toolchain)) => {
-            // Check that at runtime, we are still in this toolchain (if there is any toolchain).
-            if let Some(toolchain_runtime) =
-                env::var_os("RUSTUP_TOOLCHAIN").or_else(|| env::var_os("MULTIRUST_TOOLCHAIN"))
-            {
-                if toolchain_runtime != toolchain {
-                    show_error!(
-                        "This Miri got built with local toolchain `{toolchain}`, but now is being run under a different toolchain. \n\
-                        Make sure to run Miri in the toolchain it got built with, e.g. via `cargo +{toolchain} miri`."
-                    )
-                }
-            }
-            format!("{}/toolchains/{}", home, toolchain)
-        }
-        _ => option_env!("RUST_SYSROOT")
-            .unwrap_or_else(|| {
-                show_error!(
-                    "To build Miri without rustup, set the `RUST_SYSROOT` env var at build time",
-                )
-            })
-            .to_owned(),
-    })
-}
-
 /// Execute a compiler with the given CLI arguments and callbacks.
 fn run_compiler(
     mut args: Vec<String>,
     target_crate: bool,
     callbacks: &mut (dyn rustc_driver::Callbacks + Send),
 ) -> ! {
-    // Make sure we use the right default sysroot. The default sysroot is wrong,
-    // because `get_or_default_sysroot` in `librustc_session` bases that on `current_exe`.
-    //
-    // Make sure we always call `host_sysroot` as that also does some sanity-checks
-    // of the environment we were built in and whether it matches what we are running in.
-    let host_default_sysroot = host_sysroot();
-    // Now see if we even need to set something.
-    let sysroot_flag = "--sysroot";
-    if !args.iter().any(|e| e == sysroot_flag) {
-        // No sysroot was set, let's see if we have a custom default we want to configure.
-        let default_sysroot = if target_crate {
+    if target_crate {
+        // Miri needs a custom sysroot for target crates.
+        // If no `--sysroot` is given, the `MIRI_SYSROOT` env var is consulted to find where
+        // that sysroot lives, and that is passed to rustc.
+        let sysroot_flag = "--sysroot";
+        if !args.iter().any(|e| e == sysroot_flag) {
             // Using the built-in default here would be plain wrong, so we *require*
             // the env var to make sure things make sense.
-            Some(env::var("MIRI_SYSROOT").unwrap_or_else(|_| {
+            let miri_sysroot = env::var("MIRI_SYSROOT").unwrap_or_else(|_| {
                 show_error!(
                     "Miri was invoked in 'target' mode without `MIRI_SYSROOT` or `--sysroot` being set"
-                )
-            }))
-        } else {
-            host_default_sysroot
-        };
-        if let Some(sysroot) = default_sysroot {
-            // We need to overwrite the default that librustc_session would compute.
+                    )
+            });
+
             args.push(sysroot_flag.to_owned());
-            args.push(sysroot);
+            args.push(miri_sysroot);
         }
     }
 
@@ -330,7 +282,7 @@ fn main() {
         } else if crate_kind == "host" {
             false
         } else {
-            panic!("invalid `MIRI_BE_RUSTC` value: {:?}", crate_kind)
+            panic!("invalid `MIRI_BE_RUSTC` value: {crate_kind:?}")
         };
 
         // We cannot use `rustc_driver::main` as we need to adjust the CLI arguments.
@@ -426,7 +378,14 @@ fn main() {
         } else if arg == "-Zmiri-mute-stdout-stderr" {
             miri_config.mute_stdout_stderr = true;
         } else if arg == "-Zmiri-retag-fields" {
-            miri_config.retag_fields = true;
+            miri_config.retag_fields = RetagFields::Yes;
+        } else if let Some(retag_fields) = arg.strip_prefix("-Zmiri-retag-fields=") {
+            miri_config.retag_fields = match retag_fields {
+                "all" => RetagFields::Yes,
+                "none" => RetagFields::No,
+                "scalar" => RetagFields::OnlyScalar,
+                _ => show_error!("`-Zmiri-retag-fields` can only be `all`, `none`, or `scalar`"),
+            };
         } else if arg == "-Zmiri-track-raw-pointers" {
             eprintln!(
                 "WARNING: `-Zmiri-track-raw-pointers` has no effect; it is enabled by default"
diff --git a/src/tools/miri/src/concurrency/init_once.rs b/src/tools/miri/src/concurrency/init_once.rs
new file mode 100644
index 000000000000..eb42cdf80abb
--- /dev/null
+++ b/src/tools/miri/src/concurrency/init_once.rs
@@ -0,0 +1,228 @@
+use std::collections::VecDeque;
+use std::num::NonZeroU32;
+
+use rustc_index::vec::Idx;
+
+use super::sync::EvalContextExtPriv as _;
+use super::thread::MachineCallback;
+use super::vector_clock::VClock;
+use crate::*;
+
+declare_id!(InitOnceId);
+
+/// A thread waiting on an InitOnce object.
+struct InitOnceWaiter<'mir, 'tcx> {
+    /// The thread that is waiting.
+    thread: ThreadId,
+    /// The callback that should be executed, after the thread has been woken up.
+    callback: Box<dyn MachineCallback<'mir, 'tcx> + 'tcx>,
+}
+
+impl<'mir, 'tcx> std::fmt::Debug for InitOnceWaiter<'mir, 'tcx> {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("InitOnce")
+            .field("thread", &self.thread)
+            .field("callback", &"dyn MachineCallback")
+            .finish()
+    }
+}
+
+#[derive(Default, Debug, Copy, Clone, PartialEq, Eq)]
+/// The current status of a one time initialization.
+pub enum InitOnceStatus {
+    #[default]
+    Uninitialized,
+    Begun,
+    Complete,
+}
+
+/// The one time initialization state.
+#[derive(Default, Debug)]
+pub(super) struct InitOnce<'mir, 'tcx> {
+    status: InitOnceStatus,
+    waiters: VecDeque<InitOnceWaiter<'mir, 'tcx>>,
+    data_race: VClock,
+}
+
+impl<'mir, 'tcx> VisitTags for InitOnce<'mir, 'tcx> {
+    fn visit_tags(&self, visit: &mut dyn FnMut(SbTag)) {
+        for waiter in self.waiters.iter() {
+            waiter.callback.visit_tags(visit);
+        }
+    }
+}
+
+impl<'mir, 'tcx: 'mir> EvalContextExtPriv<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+trait EvalContextExtPriv<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
+    /// Synchronize with the previous initialization attempt of an InitOnce.
+    #[inline]
+    fn init_once_observe_attempt(&mut self, id: InitOnceId) {
+        let this = self.eval_context_mut();
+        let current_thread = this.get_active_thread();
+
+        if let Some(data_race) = &this.machine.data_race {
+            data_race.validate_lock_acquire(
+                &this.machine.threads.sync.init_onces[id].data_race,
+                current_thread,
+            );
+        }
+    }
+
+    #[inline]
+    fn init_once_wake_waiter(
+        &mut self,
+        id: InitOnceId,
+        waiter: InitOnceWaiter<'mir, 'tcx>,
+    ) -> InterpResult<'tcx> {
+        let this = self.eval_context_mut();
+        let current_thread = this.get_active_thread();
+
+        this.unblock_thread(waiter.thread);
+
+        // Call callback, with the woken-up thread as `current`.
+        this.set_active_thread(waiter.thread);
+        this.init_once_observe_attempt(id);
+        waiter.callback.call(this)?;
+        this.set_active_thread(current_thread);
+
+        Ok(())
+    }
+}
+
+impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
+    fn init_once_get_or_create_id(
+        &mut self,
+        lock_op: &OpTy<'tcx, Provenance>,
+        offset: u64,
+    ) -> InterpResult<'tcx, InitOnceId> {
+        let this = self.eval_context_mut();
+        this.init_once_get_or_create(|ecx, next_id| ecx.get_or_create_id(next_id, lock_op, offset))
+    }
+
+    /// Provides the closure with the next InitOnceId. Creates that InitOnce if the closure returns None,
+    /// otherwise returns the value from the closure.
+    #[inline]
+    fn init_once_get_or_create<F>(&mut self, existing: F) -> InterpResult<'tcx, InitOnceId>
+    where
+        F: FnOnce(
+            &mut MiriInterpCx<'mir, 'tcx>,
+            InitOnceId,
+        ) -> InterpResult<'tcx, Option<InitOnceId>>,
+    {
+        let this = self.eval_context_mut();
+        let next_index = this.machine.threads.sync.init_onces.next_index();
+        if let Some(old) = existing(this, next_index)? {
+            Ok(old)
+        } else {
+            let new_index = this.machine.threads.sync.init_onces.push(Default::default());
+            assert_eq!(next_index, new_index);
+            Ok(new_index)
+        }
+    }
+
+    #[inline]
+    fn init_once_status(&mut self, id: InitOnceId) -> InitOnceStatus {
+        let this = self.eval_context_ref();
+        this.machine.threads.sync.init_onces[id].status
+    }
+
+    /// Put the thread into the queue waiting for the initialization.
+    #[inline]
+    fn init_once_enqueue_and_block(
+        &mut self,
+        id: InitOnceId,
+        thread: ThreadId,
+        callback: Box<dyn MachineCallback<'mir, 'tcx> + 'tcx>,
+    ) {
+        let this = self.eval_context_mut();
+        let init_once = &mut this.machine.threads.sync.init_onces[id];
+        assert_ne!(init_once.status, InitOnceStatus::Complete, "queueing on complete init once");
+        init_once.waiters.push_back(InitOnceWaiter { thread, callback });
+        this.block_thread(thread);
+    }
+
+    /// Begin initializing this InitOnce. Must only be called after checking that it is currently
+    /// uninitialized.
+    #[inline]
+    fn init_once_begin(&mut self, id: InitOnceId) {
+        let this = self.eval_context_mut();
+        let init_once = &mut this.machine.threads.sync.init_onces[id];
+        assert_eq!(
+            init_once.status,
+            InitOnceStatus::Uninitialized,
+            "begining already begun or complete init once"
+        );
+        init_once.status = InitOnceStatus::Begun;
+    }
+
+    #[inline]
+    fn init_once_complete(&mut self, id: InitOnceId) -> InterpResult<'tcx> {
+        let this = self.eval_context_mut();
+        let current_thread = this.get_active_thread();
+        let init_once = &mut this.machine.threads.sync.init_onces[id];
+
+        assert_eq!(
+            init_once.status,
+            InitOnceStatus::Begun,
+            "completing already complete or uninit init once"
+        );
+
+        init_once.status = InitOnceStatus::Complete;
+
+        // Each complete happens-before the end of the wait
+        if let Some(data_race) = &this.machine.data_race {
+            data_race.validate_lock_release(&mut init_once.data_race, current_thread);
+        }
+
+        // Wake up everyone.
+        // need to take the queue to avoid having `this` be borrowed multiple times
+        for waiter in std::mem::take(&mut init_once.waiters) {
+            this.init_once_wake_waiter(id, waiter)?;
+        }
+
+        Ok(())
+    }
+
+    #[inline]
+    fn init_once_fail(&mut self, id: InitOnceId) -> InterpResult<'tcx> {
+        let this = self.eval_context_mut();
+        let current_thread = this.get_active_thread();
+        let init_once = &mut this.machine.threads.sync.init_onces[id];
+        assert_eq!(
+            init_once.status,
+            InitOnceStatus::Begun,
+            "failing already completed or uninit init once"
+        );
+
+        // Each complete happens-before the end of the wait
+        if let Some(data_race) = &this.machine.data_race {
+            data_race.validate_lock_release(&mut init_once.data_race, current_thread);
+        }
+
+        // Wake up one waiting thread, so they can go ahead and try to init this.
+        if let Some(waiter) = init_once.waiters.pop_front() {
+            this.init_once_wake_waiter(id, waiter)?;
+        } else {
+            // Nobody there to take this, so go back to 'uninit'
+            init_once.status = InitOnceStatus::Uninitialized;
+        }
+
+        Ok(())
+    }
+
+    /// Synchronize with the previous completion of an InitOnce.
+    /// Must only be called after checking that it is complete.
+    #[inline]
+    fn init_once_observe_completed(&mut self, id: InitOnceId) {
+        let this = self.eval_context_mut();
+
+        assert_eq!(
+            this.init_once_status(id),
+            InitOnceStatus::Complete,
+            "observing the completion of incomplete init once"
+        );
+
+        this.init_once_observe_attempt(id);
+    }
+}
diff --git a/src/tools/miri/src/concurrency/mod.rs b/src/tools/miri/src/concurrency/mod.rs
index 61ef3d5640e0..45903107f171 100644
--- a/src/tools/miri/src/concurrency/mod.rs
+++ b/src/tools/miri/src/concurrency/mod.rs
@@ -1,6 +1,8 @@
 pub mod data_race;
 mod range_object_map;
+#[macro_use]
 pub mod sync;
+pub mod init_once;
 pub mod thread;
 mod vector_clock;
 pub mod weak_memory;
diff --git a/src/tools/miri/src/concurrency/sync.rs b/src/tools/miri/src/concurrency/sync.rs
index 464f452ca769..ba5ae852c5a9 100644
--- a/src/tools/miri/src/concurrency/sync.rs
+++ b/src/tools/miri/src/concurrency/sync.rs
@@ -7,9 +7,15 @@ use log::trace;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_index::vec::{Idx, IndexVec};
 
+use super::init_once::InitOnce;
 use super::vector_clock::VClock;
 use crate::*;
 
+pub trait SyncId {
+    fn from_u32(id: u32) -> Self;
+    fn to_u32(&self) -> u32;
+}
+
 /// We cannot use the `newtype_index!` macro because we have to use 0 as a
 /// sentinel value meaning that the identifier is not assigned. This is because
 /// the pthreads static initializers initialize memory with zeros (see the
@@ -21,11 +27,14 @@ macro_rules! declare_id {
         #[derive(Clone, Copy, Debug, PartialOrd, Ord, PartialEq, Eq, Hash)]
         pub struct $name(NonZeroU32);
 
-        impl $name {
+        impl SyncId for $name {
             // Panics if `id == 0`.
-            pub fn from_u32(id: u32) -> Self {
+            fn from_u32(id: u32) -> Self {
                 Self(NonZeroU32::new(id).unwrap())
             }
+            fn to_u32(&self) -> u32 {
+                self.0.get()
+            }
         }
 
         impl Idx for $name {
@@ -107,13 +116,25 @@ struct RwLock {
 
 declare_id!(CondvarId);
 
+#[derive(Debug, Copy, Clone)]
+pub enum RwLockMode {
+    Read,
+    Write,
+}
+
+#[derive(Debug)]
+pub enum CondvarLock {
+    Mutex(MutexId),
+    RwLock { id: RwLockId, mode: RwLockMode },
+}
+
 /// A thread waiting on a conditional variable.
 #[derive(Debug)]
 struct CondvarWaiter {
     /// The thread that is waiting on this variable.
     thread: ThreadId,
-    /// The mutex on which the thread is waiting.
-    mutex: MutexId,
+    /// The mutex or rwlock on which the thread is waiting.
+    lock: CondvarLock,
 }
 
 /// The conditional variable state.
@@ -151,16 +172,58 @@ struct FutexWaiter {
 
 /// The state of all synchronization variables.
 #[derive(Default, Debug)]
-pub(crate) struct SynchronizationState {
+pub(crate) struct SynchronizationState<'mir, 'tcx> {
     mutexes: IndexVec<MutexId, Mutex>,
     rwlocks: IndexVec<RwLockId, RwLock>,
     condvars: IndexVec<CondvarId, Condvar>,
     futexes: FxHashMap<u64, Futex>,
+    pub(super) init_onces: IndexVec<InitOnceId, InitOnce<'mir, 'tcx>>,
+}
+
+impl<'mir, 'tcx> VisitTags for SynchronizationState<'mir, 'tcx> {
+    fn visit_tags(&self, visit: &mut dyn FnMut(SbTag)) {
+        for init_once in self.init_onces.iter() {
+            init_once.visit_tags(visit);
+        }
+    }
 }
 
 // Private extension trait for local helper methods
 impl<'mir, 'tcx: 'mir> EvalContextExtPriv<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
-trait EvalContextExtPriv<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
+pub(super) trait EvalContextExtPriv<'mir, 'tcx: 'mir>:
+    crate::MiriInterpCxExt<'mir, 'tcx>
+{
+    #[inline]
+    // Miri sync structures contain zero-initialized ids stored at some offset behind a pointer
+    fn get_or_create_id<Id: SyncId>(
+        &mut self,
+        next_id: Id,
+        lock_op: &OpTy<'tcx, Provenance>,
+        offset: u64,
+    ) -> InterpResult<'tcx, Option<Id>> {
+        let this = self.eval_context_mut();
+        let value_place =
+            this.deref_operand_and_offset(lock_op, offset, this.machine.layouts.u32)?;
+
+        let (old, success) = this
+            .atomic_compare_exchange_scalar(
+                &value_place,
+                &ImmTy::from_uint(0u32, this.machine.layouts.u32),
+                Scalar::from_u32(next_id.to_u32()),
+                AtomicRwOrd::Relaxed, // deliberately *no* synchronization
+                AtomicReadOrd::Relaxed,
+                false,
+            )?
+            .to_scalar_pair();
+
+        Ok(if success.to_bool().expect("compare_exchange's second return value is a bool") {
+            // Caller of the closure needs to allocate next_id
+            None
+        } else {
+            Some(Id::from_u32(old.to_u32().expect("layout is u32")))
+        })
+    }
+
     /// Take a reader out of the queue waiting for the lock.
     /// Returns `true` if some thread got the rwlock.
     #[inline]
@@ -210,11 +273,31 @@ trait EvalContextExtPriv<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
 // situations.
 impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
 pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
-    #[inline]
-    /// Create state for a new mutex.
-    fn mutex_create(&mut self) -> MutexId {
+    fn mutex_get_or_create_id(
+        &mut self,
+        lock_op: &OpTy<'tcx, Provenance>,
+        offset: u64,
+    ) -> InterpResult<'tcx, MutexId> {
         let this = self.eval_context_mut();
-        this.machine.threads.sync.mutexes.push(Default::default())
+        this.mutex_get_or_create(|ecx, next_id| ecx.get_or_create_id(next_id, lock_op, offset))
+    }
+
+    fn rwlock_get_or_create_id(
+        &mut self,
+        lock_op: &OpTy<'tcx, Provenance>,
+        offset: u64,
+    ) -> InterpResult<'tcx, RwLockId> {
+        let this = self.eval_context_mut();
+        this.rwlock_get_or_create(|ecx, next_id| ecx.get_or_create_id(next_id, lock_op, offset))
+    }
+
+    fn condvar_get_or_create_id(
+        &mut self,
+        lock_op: &OpTy<'tcx, Provenance>,
+        offset: u64,
+    ) -> InterpResult<'tcx, CondvarId> {
+        let this = self.eval_context_mut();
+        this.condvar_get_or_create(|ecx, next_id| ecx.get_or_create_id(next_id, lock_op, offset))
     }
 
     #[inline]
@@ -301,8 +384,8 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         }
     }
 
-    #[inline]
     /// Put the thread into the queue waiting for the mutex.
+    #[inline]
     fn mutex_enqueue_and_block(&mut self, id: MutexId, thread: ThreadId) {
         let this = self.eval_context_mut();
         assert!(this.mutex_is_locked(id), "queing on unlocked mutex");
@@ -310,16 +393,9 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         this.block_thread(thread);
     }
 
-    #[inline]
-    /// Create state for a new read write lock.
-    fn rwlock_create(&mut self) -> RwLockId {
-        let this = self.eval_context_mut();
-        this.machine.threads.sync.rwlocks.push(Default::default())
-    }
-
-    #[inline]
     /// Provides the closure with the next RwLockId. Creates that RwLock if the closure returns None,
     /// otherwise returns the value from the closure
+    #[inline]
     fn rwlock_get_or_create<F>(&mut self, existing: F) -> InterpResult<'tcx, RwLockId>
     where
         F: FnOnce(&mut MiriInterpCx<'mir, 'tcx>, RwLockId) -> InterpResult<'tcx, Option<RwLockId>>,
@@ -349,8 +425,8 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         rwlock.writer.is_some() || rwlock.readers.is_empty().not()
     }
 
-    #[inline]
     /// Check if write locked.
+    #[inline]
     fn rwlock_is_write_locked(&self, id: RwLockId) -> bool {
         let this = self.eval_context_ref();
         let rwlock = &this.machine.threads.sync.rwlocks[id];
@@ -407,8 +483,8 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         true
     }
 
-    #[inline]
     /// Put the reader in the queue waiting for the lock and block it.
+    #[inline]
     fn rwlock_enqueue_and_block_reader(&mut self, id: RwLockId, reader: ThreadId) {
         let this = self.eval_context_mut();
         assert!(this.rwlock_is_write_locked(id), "read-queueing on not write locked rwlock");
@@ -416,8 +492,8 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         this.block_thread(reader);
     }
 
-    #[inline]
     /// Lock by setting the writer that owns the lock.
+    #[inline]
     fn rwlock_writer_lock(&mut self, id: RwLockId, writer: ThreadId) {
         let this = self.eval_context_mut();
         assert!(!this.rwlock_is_locked(id), "the rwlock is already locked");
@@ -429,8 +505,8 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         }
     }
 
-    #[inline]
     /// Try to unlock by removing the writer.
+    #[inline]
     fn rwlock_writer_unlock(&mut self, id: RwLockId, expected_writer: ThreadId) -> bool {
         let this = self.eval_context_mut();
         let rwlock = &mut this.machine.threads.sync.rwlocks[id];
@@ -467,8 +543,8 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         }
     }
 
-    #[inline]
     /// Put the writer in the queue waiting for the lock.
+    #[inline]
     fn rwlock_enqueue_and_block_writer(&mut self, id: RwLockId, writer: ThreadId) {
         let this = self.eval_context_mut();
         assert!(this.rwlock_is_locked(id), "write-queueing on unlocked rwlock");
@@ -476,16 +552,9 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         this.block_thread(writer);
     }
 
-    #[inline]
-    /// Create state for a new conditional variable.
-    fn condvar_create(&mut self) -> CondvarId {
-        let this = self.eval_context_mut();
-        this.machine.threads.sync.condvars.push(Default::default())
-    }
-
-    #[inline]
     /// Provides the closure with the next CondvarId. Creates that Condvar if the closure returns None,
     /// otherwise returns the value from the closure
+    #[inline]
     fn condvar_get_or_create<F>(&mut self, existing: F) -> InterpResult<'tcx, CondvarId>
     where
         F: FnOnce(
@@ -504,24 +573,24 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         }
     }
 
-    #[inline]
     /// Is the conditional variable awaited?
+    #[inline]
     fn condvar_is_awaited(&mut self, id: CondvarId) -> bool {
         let this = self.eval_context_mut();
         !this.machine.threads.sync.condvars[id].waiters.is_empty()
     }
 
     /// Mark that the thread is waiting on the conditional variable.
-    fn condvar_wait(&mut self, id: CondvarId, thread: ThreadId, mutex: MutexId) {
+    fn condvar_wait(&mut self, id: CondvarId, thread: ThreadId, lock: CondvarLock) {
         let this = self.eval_context_mut();
         let waiters = &mut this.machine.threads.sync.condvars[id].waiters;
         assert!(waiters.iter().all(|waiter| waiter.thread != thread), "thread is already waiting");
-        waiters.push_back(CondvarWaiter { thread, mutex });
+        waiters.push_back(CondvarWaiter { thread, lock });
     }
 
     /// Wake up some thread (if there is any) sleeping on the conditional
     /// variable.
-    fn condvar_signal(&mut self, id: CondvarId) -> Option<(ThreadId, MutexId)> {
+    fn condvar_signal(&mut self, id: CondvarId) -> Option<(ThreadId, CondvarLock)> {
         let this = self.eval_context_mut();
         let current_thread = this.get_active_thread();
         let condvar = &mut this.machine.threads.sync.condvars[id];
@@ -535,7 +604,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             if let Some(data_race) = data_race {
                 data_race.validate_lock_acquire(&condvar.data_race, waiter.thread);
             }
-            (waiter.thread, waiter.mutex)
+            (waiter.thread, waiter.lock)
         })
     }
 
diff --git a/src/tools/miri/src/concurrency/thread.rs b/src/tools/miri/src/concurrency/thread.rs
index ec1da4138d44..ac5dcbf0f4f2 100644
--- a/src/tools/miri/src/concurrency/thread.rs
+++ b/src/tools/miri/src/concurrency/thread.rs
@@ -30,8 +30,7 @@ pub enum SchedulingAction {
     Stop,
 }
 
-/// Timeout callbacks can be created by synchronization primitives to tell the
-/// scheduler that they should be called once some period of time passes.
+/// Trait for callbacks that can be executed when some event happens, such as after a timeout.
 pub trait MachineCallback<'mir, 'tcx>: VisitTags {
     fn call(&self, ecx: &mut InterpCx<'mir, 'tcx, MiriMachine<'mir, 'tcx>>) -> InterpResult<'tcx>;
 }
@@ -269,7 +268,7 @@ pub struct ThreadManager<'mir, 'tcx> {
     threads: IndexVec<ThreadId, Thread<'mir, 'tcx>>,
     /// This field is pub(crate) because the synchronization primitives
     /// (`crate::sync`) need a way to access it.
-    pub(crate) sync: SynchronizationState,
+    pub(crate) sync: SynchronizationState<'mir, 'tcx>,
     /// A mapping from a thread-local static to an allocation id of a thread
     /// specific allocation.
     thread_local_alloc_ids: RefCell<FxHashMap<(DefId, ThreadId), Pointer<Provenance>>>,
@@ -303,7 +302,7 @@ impl VisitTags for ThreadManager<'_, '_> {
             timeout_callbacks,
             active_thread: _,
             yield_active_thread: _,
-            sync: _,
+            sync,
         } = self;
 
         for thread in threads {
@@ -315,6 +314,7 @@ impl VisitTags for ThreadManager<'_, '_> {
         for callback in timeout_callbacks.values() {
             callback.callback.visit_tags(visit);
         }
+        sync.visit_tags(visit);
     }
 }
 
@@ -870,6 +870,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         this.machine.threads.active_thread_stack_mut()
     }
 
+    /// Set the name of the current thread. The buffer must not include the null terminator.
     #[inline]
     fn set_thread_name(&mut self, thread: ThreadId, new_thread_name: Vec<u8>) {
         let this = self.eval_context_mut();
diff --git a/src/tools/miri/src/concurrency/vector_clock.rs b/src/tools/miri/src/concurrency/vector_clock.rs
index 32449f8eb188..e7e5b35ac2cd 100644
--- a/src/tools/miri/src/concurrency/vector_clock.rs
+++ b/src/tools/miri/src/concurrency/vector_clock.rs
@@ -399,7 +399,7 @@ mod tests {
 
         //Test partial_cmp
         let compare = l.partial_cmp(&r);
-        assert_eq!(compare, o, "Invalid comparison\n l: {:?}\n r: {:?}", l, r);
+        assert_eq!(compare, o, "Invalid comparison\n l: {l:?}\n r: {r:?}");
         let alt_compare = r.partial_cmp(&l);
         assert_eq!(
             alt_compare,
diff --git a/src/tools/miri/src/concurrency/weak_memory.rs b/src/tools/miri/src/concurrency/weak_memory.rs
index 9d7a49c0b430..f2a365729549 100644
--- a/src/tools/miri/src/concurrency/weak_memory.rs
+++ b/src/tools/miri/src/concurrency/weak_memory.rs
@@ -17,7 +17,7 @@
 //! load to the first, as a result of C++20's coherence-ordered before rules.
 //!
 //! Rust follows the C++20 memory model (except for the Consume ordering and some operations not performable through C++'s
-//! std::atomic<T> API). It is therefore possible for this implementation to generate behaviours never observable when the
+//! `std::atomic<T>` API). It is therefore possible for this implementation to generate behaviours never observable when the
 //! same program is compiled and run natively. Unfortunately, no literature exists at the time of writing which proposes
 //! an implementable and C++20-compatible relaxed memory model that supports all atomic operation existing in Rust. The closest one is
 //! A Promising Semantics for Relaxed-Memory Concurrency by Jeehoon Kang et al. (<https://www.cs.tau.ac.il/~orilahav/papers/popl17.pdf>)
diff --git a/src/tools/miri/src/diagnostics.rs b/src/tools/miri/src/diagnostics.rs
index ecfe0cd3f8a6..ec81ffd3cd5c 100644
--- a/src/tools/miri/src/diagnostics.rs
+++ b/src/tools/miri/src/diagnostics.rs
@@ -263,7 +263,7 @@ pub fn report_error<'tcx, 'mir>(
     msg.insert(0, e.to_string());
     report_msg(
         DiagLevel::Error,
-        &if let Some(title) = title { format!("{}: {}", title, msg[0]) } else { msg[0].clone() },
+        &if let Some(title) = title { format!("{title}: {}", msg[0]) } else { msg[0].clone() },
         msg,
         vec![],
         helps,
diff --git a/src/tools/miri/src/eval.rs b/src/tools/miri/src/eval.rs
index b211f3c5f713..81132db94cf1 100644
--- a/src/tools/miri/src/eval.rs
+++ b/src/tools/miri/src/eval.rs
@@ -126,7 +126,7 @@ pub struct MiriConfig {
     /// Report the current instruction being executed every N basic blocks.
     pub report_progress: Option<u32>,
     /// Whether Stacked Borrows retagging should recurse into fields of datatypes.
-    pub retag_fields: bool,
+    pub retag_fields: RetagFields,
     /// The location of a shared object file to load when calling external functions
     /// FIXME! consider allowing users to specify paths to multiple SO files, or to a directory
     pub external_so_file: Option<PathBuf>,
@@ -163,7 +163,7 @@ impl Default for MiriConfig {
             mute_stdout_stderr: false,
             preemption_rate: 0.01, // 1%
             report_progress: None,
-            retag_fields: false,
+            retag_fields: RetagFields::OnlyScalar,
             external_so_file: None,
             gc_interval: 10_000,
             num_cpus: 1,
diff --git a/src/tools/miri/src/helpers.rs b/src/tools/miri/src/helpers.rs
index 15833fe42adc..f98727186c48 100644
--- a/src/tools/miri/src/helpers.rs
+++ b/src/tools/miri/src/helpers.rs
@@ -1,6 +1,7 @@
 pub mod convert;
 
 use std::cmp;
+use std::iter;
 use std::mem;
 use std::num::NonZeroUsize;
 use std::time::Duration;
@@ -107,7 +108,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     /// Gets an instance for a path.
     fn resolve_path(&self, path: &[&str]) -> ty::Instance<'tcx> {
         self.try_resolve_path(path)
-            .unwrap_or_else(|| panic!("failed to find required Rust item: {:?}", path))
+            .unwrap_or_else(|| panic!("failed to find required Rust item: {path:?}"))
     }
 
     /// Evaluates the scalar at the specified path. Returns Some(val)
@@ -505,7 +506,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             RejectOpWith::WarningWithoutBacktrace => {
                 this.tcx
                     .sess
-                    .warn(&format!("{} was made to return an error due to isolation", op_name));
+                    .warn(format!("{op_name} was made to return an error due to isolation"));
                 Ok(())
             }
             RejectOpWith::Warning => {
@@ -735,6 +736,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         })
     }
 
+    /// Read a sequence of bytes until the first null terminator.
     fn read_c_str<'a>(&'a self, ptr: Pointer<Option<Provenance>>) -> InterpResult<'tcx, &'a [u8]>
     where
         'tcx: 'a,
@@ -761,6 +763,30 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         this.read_bytes_ptr_strip_provenance(ptr, len)
     }
 
+    /// Helper function to write a sequence of bytes with an added null-terminator, which is what
+    /// the Unix APIs usually handle. This function returns `Ok((false, length))` without trying
+    /// to write if `size` is not large enough to fit the contents of `c_str` plus a null
+    /// terminator. It returns `Ok((true, length))` if the writing process was successful. The
+    /// string length returned does include the null terminator.
+    fn write_c_str(
+        &mut self,
+        c_str: &[u8],
+        ptr: Pointer<Option<Provenance>>,
+        size: u64,
+    ) -> InterpResult<'tcx, (bool, u64)> {
+        // If `size` is smaller or equal than `bytes.len()`, writing `bytes` plus the required null
+        // terminator to memory using the `ptr` pointer would cause an out-of-bounds access.
+        let string_length = u64::try_from(c_str.len()).unwrap();
+        let string_length = string_length.checked_add(1).unwrap();
+        if size < string_length {
+            return Ok((false, string_length));
+        }
+        self.eval_context_mut()
+            .write_bytes_ptr(ptr, c_str.iter().copied().chain(iter::once(0u8)))?;
+        Ok((true, string_length))
+    }
+
+    /// Read a sequence of u16 until the first null terminator.
     fn read_wide_str(&self, mut ptr: Pointer<Option<Provenance>>) -> InterpResult<'tcx, Vec<u16>> {
         let this = self.eval_context_ref();
         let size2 = Size::from_bytes(2);
@@ -783,6 +809,39 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         Ok(wchars)
     }
 
+    /// Helper function to write a sequence of u16 with an added 0x0000-terminator, which is what
+    /// the Windows APIs usually handle. This function returns `Ok((false, length))` without trying
+    /// to write if `size` is not large enough to fit the contents of `os_string` plus a null
+    /// terminator. It returns `Ok((true, length))` if the writing process was successful. The
+    /// string length returned does include the null terminator. Length is measured in units of
+    /// `u16.`
+    fn write_wide_str(
+        &mut self,
+        wide_str: &[u16],
+        ptr: Pointer<Option<Provenance>>,
+        size: u64,
+    ) -> InterpResult<'tcx, (bool, u64)> {
+        // If `size` is smaller or equal than `bytes.len()`, writing `bytes` plus the required
+        // 0x0000 terminator to memory would cause an out-of-bounds access.
+        let string_length = u64::try_from(wide_str.len()).unwrap();
+        let string_length = string_length.checked_add(1).unwrap();
+        if size < string_length {
+            return Ok((false, string_length));
+        }
+
+        // Store the UTF-16 string.
+        let size2 = Size::from_bytes(2);
+        let this = self.eval_context_mut();
+        let mut alloc = this
+            .get_ptr_alloc_mut(ptr, size2 * string_length, Align::from_bytes(2).unwrap())?
+            .unwrap(); // not a ZST, so we will get a result
+        for (offset, wchar) in wide_str.iter().copied().chain(iter::once(0x0000)).enumerate() {
+            let offset = u64::try_from(offset).unwrap();
+            alloc.write_scalar(alloc_range(size2 * offset, size2), Scalar::from_u16(wchar))?;
+        }
+        Ok((true, string_length))
+    }
+
     /// Check that the ABI is what we expect.
     fn check_abi<'a>(&self, abi: Abi, exp_abi: Abi) -> InterpResult<'a, ()> {
         if self.eval_context_ref().machine.enforce_abi && abi != exp_abi {
diff --git a/src/tools/miri/src/lib.rs b/src/tools/miri/src/lib.rs
index 8d754bad1b3c..8028ce753548 100644
--- a/src/tools/miri/src/lib.rs
+++ b/src/tools/miri/src/lib.rs
@@ -3,12 +3,12 @@
 #![feature(never_type)]
 #![feature(try_blocks)]
 #![feature(io_error_more)]
-#![feature(int_log)]
 #![feature(variant_count)]
 #![feature(yeet_expr)]
 #![feature(is_some_and)]
 #![feature(nonzero_ops)]
 #![feature(local_key_cell_methods)]
+#![feature(is_terminal)]
 // Configure clippy and other lints
 #![allow(
     clippy::collapsible_else_if,
@@ -26,6 +26,7 @@
     clippy::type_complexity,
     clippy::single_element_loop,
     clippy::needless_return,
+    clippy::bool_to_int_with_if,
     // We are not implementing queries here so it's fine
     rustc::potential_query_instability
 )]
@@ -36,6 +37,8 @@
     clippy::cast_lossless,
     clippy::cast_possible_truncation,
 )]
+// Needed for rustdoc from bootstrap (with `-Znormalize-docs`).
+#![recursion_limit = "256"]
 
 extern crate rustc_apfloat;
 extern crate rustc_ast;
@@ -82,34 +85,28 @@ pub use crate::shims::EvalContextExt as _;
 
 pub use crate::clock::{Clock, Instant};
 pub use crate::concurrency::{
-    data_race::{
-        AtomicFenceOrd, AtomicReadOrd, AtomicRwOrd, AtomicWriteOrd,
-        EvalContextExt as DataRaceEvalContextExt,
-    },
-    sync::{CondvarId, EvalContextExt as SyncEvalContextExt, MutexId, RwLockId},
-    thread::{
-        EvalContextExt as ThreadsEvalContextExt, SchedulingAction, ThreadId, ThreadManager,
-        ThreadState, Time,
-    },
+    data_race::{AtomicFenceOrd, AtomicReadOrd, AtomicRwOrd, AtomicWriteOrd, EvalContextExt as _},
+    init_once::{EvalContextExt as _, InitOnceId},
+    sync::{CondvarId, EvalContextExt as _, MutexId, RwLockId, SyncId},
+    thread::{EvalContextExt as _, SchedulingAction, ThreadId, ThreadManager, ThreadState, Time},
 };
 pub use crate::diagnostics::{
-    report_error, EvalContextExt as DiagnosticsEvalContextExt, NonHaltingDiagnostic,
-    TerminationInfo,
+    report_error, EvalContextExt as _, NonHaltingDiagnostic, TerminationInfo,
 };
 pub use crate::eval::{
     create_ecx, eval_entry, AlignmentCheck, BacktraceStyle, IsolatedOp, MiriConfig, RejectOpWith,
 };
-pub use crate::helpers::{CurrentSpan, EvalContextExt as HelpersEvalContextExt};
+pub use crate::helpers::{CurrentSpan, EvalContextExt as _};
 pub use crate::intptrcast::ProvenanceMode;
 pub use crate::machine::{
-    AllocExtra, FrameData, MiriInterpCx, MiriInterpCxExt, MiriMachine, MiriMemoryKind, Provenance,
-    ProvenanceExtra, PAGE_SIZE, STACK_ADDR, STACK_SIZE,
+    AllocExtra, FrameData, MiriInterpCx, MiriInterpCxExt, MiriMachine, MiriMemoryKind,
+    PrimitiveLayouts, Provenance, ProvenanceExtra, PAGE_SIZE, STACK_ADDR, STACK_SIZE,
 };
 pub use crate::mono_hash_map::MonoHashMap;
-pub use crate::operator::EvalContextExt as OperatorEvalContextExt;
+pub use crate::operator::EvalContextExt as _;
 pub use crate::range_map::RangeMap;
 pub use crate::stacked_borrows::{
-    CallId, EvalContextExt as StackedBorEvalContextExt, Item, Permission, SbTag, Stack, Stacks,
+    CallId, EvalContextExt as _, Item, Permission, RetagFields, SbTag, Stack, Stacks,
 };
 pub use crate::tag_gc::{EvalContextExt as _, VisitTags};
 
diff --git a/src/tools/miri/src/machine.rs b/src/tools/miri/src/machine.rs
index 20ae908fce87..231a99c1d034 100644
--- a/src/tools/miri/src/machine.rs
+++ b/src/tools/miri/src/machine.rs
@@ -191,12 +191,12 @@ impl interpret::Provenance for Provenance {
             Provenance::Concrete { alloc_id, sb } => {
                 // Forward `alternate` flag to `alloc_id` printing.
                 if f.alternate() {
-                    write!(f, "[{:#?}]", alloc_id)?;
+                    write!(f, "[{alloc_id:#?}]")?;
                 } else {
-                    write!(f, "[{:?}]", alloc_id)?;
+                    write!(f, "[{alloc_id:?}]")?;
                 }
                 // Print Stacked Borrows tag.
-                write!(f, "{:?}", sb)?;
+                write!(f, "{sb:?}")?;
             }
             Provenance::Wildcard => {
                 write!(f, "[wildcard]")?;
@@ -276,10 +276,14 @@ pub struct PrimitiveLayouts<'tcx> {
     pub i8: TyAndLayout<'tcx>,
     pub i16: TyAndLayout<'tcx>,
     pub i32: TyAndLayout<'tcx>,
+    pub i64: TyAndLayout<'tcx>,
+    pub i128: TyAndLayout<'tcx>,
     pub isize: TyAndLayout<'tcx>,
     pub u8: TyAndLayout<'tcx>,
     pub u16: TyAndLayout<'tcx>,
     pub u32: TyAndLayout<'tcx>,
+    pub u64: TyAndLayout<'tcx>,
+    pub u128: TyAndLayout<'tcx>,
     pub usize: TyAndLayout<'tcx>,
     pub bool: TyAndLayout<'tcx>,
     pub mut_raw_ptr: TyAndLayout<'tcx>,   // *mut ()
@@ -296,16 +300,42 @@ impl<'mir, 'tcx: 'mir> PrimitiveLayouts<'tcx> {
             i8: layout_cx.layout_of(tcx.types.i8)?,
             i16: layout_cx.layout_of(tcx.types.i16)?,
             i32: layout_cx.layout_of(tcx.types.i32)?,
+            i64: layout_cx.layout_of(tcx.types.i64)?,
+            i128: layout_cx.layout_of(tcx.types.i128)?,
             isize: layout_cx.layout_of(tcx.types.isize)?,
             u8: layout_cx.layout_of(tcx.types.u8)?,
             u16: layout_cx.layout_of(tcx.types.u16)?,
             u32: layout_cx.layout_of(tcx.types.u32)?,
+            u64: layout_cx.layout_of(tcx.types.u64)?,
+            u128: layout_cx.layout_of(tcx.types.u128)?,
             usize: layout_cx.layout_of(tcx.types.usize)?,
             bool: layout_cx.layout_of(tcx.types.bool)?,
             mut_raw_ptr: layout_cx.layout_of(mut_raw_ptr)?,
             const_raw_ptr: layout_cx.layout_of(const_raw_ptr)?,
         })
     }
+
+    pub fn uint(&self, size: Size) -> Option<TyAndLayout<'tcx>> {
+        match size.bits() {
+            8 => Some(self.u8),
+            16 => Some(self.u16),
+            32 => Some(self.u32),
+            64 => Some(self.u64),
+            128 => Some(self.u128),
+            _ => None,
+        }
+    }
+
+    pub fn int(&self, size: Size) -> Option<TyAndLayout<'tcx>> {
+        match size.bits() {
+            8 => Some(self.i8),
+            16 => Some(self.i16),
+            32 => Some(self.i32),
+            64 => Some(self.i64),
+            128 => Some(self.i128),
+            _ => None,
+        }
+    }
 }
 
 /// The machine itself.
@@ -421,8 +451,10 @@ pub struct MiriMachine<'mir, 'tcx> {
     pub(crate) basic_block_count: u64,
 
     /// Handle of the optional shared object file for external functions.
-    #[cfg(unix)]
+    #[cfg(target_os = "linux")]
     pub external_so_lib: Option<(libloading::Library, std::path::PathBuf)>,
+    #[cfg(not(target_os = "linux"))]
+    pub external_so_lib: Option<!>,
 
     /// Run a garbage collector for SbTags every N basic blocks.
     pub(crate) gc_interval: u32,
@@ -485,7 +517,7 @@ impl<'mir, 'tcx> MiriMachine<'mir, 'tcx> {
             report_progress: config.report_progress,
             basic_block_count: 0,
             clock: Clock::new(config.isolated_op == IsolatedOp::Allow),
-            #[cfg(unix)]
+            #[cfg(target_os = "linux")]
             external_so_lib: config.external_so_file.as_ref().map(|lib_file_path| {
                 let target_triple = layout_cx.tcx.sess.opts.target_triple.triple();
                 // Check if host target == the session target.
@@ -507,6 +539,10 @@ impl<'mir, 'tcx> MiriMachine<'mir, 'tcx> {
                     lib_file_path.clone(),
                 )
             }),
+            #[cfg(not(target_os = "linux"))]
+            external_so_lib: config.external_so_file.as_ref().map(|_| {
+                panic!("loading external .so files is only supported on Linux")
+            }),
             gc_interval: config.gc_interval,
             since_gc: 0,
             num_cpus: config.num_cpus,
@@ -648,7 +684,6 @@ impl VisitTags for MiriMachine<'_, '_> {
             preemption_rate: _,
             report_progress: _,
             basic_block_count: _,
-            #[cfg(unix)]
             external_so_lib: _,
             gc_interval: _,
             since_gc: _,
diff --git a/src/tools/miri/src/range_map.rs b/src/tools/miri/src/range_map.rs
index c77ea63b0873..c8ff06a36652 100644
--- a/src/tools/miri/src/range_map.rs
+++ b/src/tools/miri/src/range_map.rs
@@ -40,7 +40,7 @@ impl<T> RangeMap<T> {
         let mut left = 0usize; // inclusive
         let mut right = self.v.len(); // exclusive
         loop {
-            debug_assert!(left < right, "find_offset: offset {} is out-of-bounds", offset);
+            debug_assert!(left < right, "find_offset: offset {offset} is out-of-bounds");
             let candidate = left.checked_add(right).unwrap() / 2;
             let elem = &self.v[candidate];
             if offset < elem.range.start {
@@ -91,6 +91,10 @@ impl<T> RangeMap<T> {
         self.v.iter_mut().map(|elem| &mut elem.data)
     }
 
+    pub fn iter_all(&self) -> impl Iterator<Item = (ops::Range<u64>, &T)> {
+        self.v.iter().map(|elem| (elem.range.clone(), &elem.data))
+    }
+
     // Splits the element situated at the given `index`, such that the 2nd one starts at offset
     // `split_offset`. Do nothing if the element already starts there.
     // Returns whether a split was necessary.
diff --git a/src/tools/miri/src/shims/env.rs b/src/tools/miri/src/shims/env.rs
index 076d3878de2a..bf6c1f875629 100644
--- a/src/tools/miri/src/shims/env.rs
+++ b/src/tools/miri/src/shims/env.rs
@@ -144,7 +144,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         name_op: &OpTy<'tcx, Provenance>, // LPCWSTR
         buf_op: &OpTy<'tcx, Provenance>,  // LPWSTR
         size_op: &OpTy<'tcx, Provenance>, // DWORD
-    ) -> InterpResult<'tcx, u32> {
+    ) -> InterpResult<'tcx, Scalar<Provenance>> {
         // ^ Returns DWORD (u32 on Windows)
 
         let this = self.eval_context_mut();
@@ -165,12 +165,14 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 let buf_ptr = this.read_pointer(buf_op)?;
                 // `buf_size` represents the size in characters.
                 let buf_size = u64::from(this.read_scalar(size_op)?.to_u32()?);
-                windows_check_buffer_size(this.write_os_str_to_wide_str(&var, buf_ptr, buf_size)?)
+                Scalar::from_u32(windows_check_buffer_size(
+                    this.write_os_str_to_wide_str(&var, buf_ptr, buf_size)?,
+                ))
             }
             None => {
                 let envvar_not_found = this.eval_windows("c", "ERROR_ENVVAR_NOT_FOUND")?;
                 this.set_last_error(envvar_not_found)?;
-                0 // return zero upon failure
+                Scalar::from_u32(0) // return zero upon failure
             }
         })
     }
@@ -200,14 +202,14 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn FreeEnvironmentStringsW(
         &mut self,
         env_block_op: &OpTy<'tcx, Provenance>,
-    ) -> InterpResult<'tcx, i32> {
+    ) -> InterpResult<'tcx, Scalar<Provenance>> {
         let this = self.eval_context_mut();
         this.assert_target_os("windows", "FreeEnvironmentStringsW");
 
         let env_block_ptr = this.read_pointer(env_block_op)?;
         let result = this.deallocate_ptr(env_block_ptr, None, MiriMemoryKind::Runtime.into());
         // If the function succeeds, the return value is nonzero.
-        Ok(i32::from(result.is_ok()))
+        Ok(Scalar::from_i32(i32::from(result.is_ok())))
     }
 
     fn setenv(
@@ -249,7 +251,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         &mut self,
         name_op: &OpTy<'tcx, Provenance>,  // LPCWSTR
         value_op: &OpTy<'tcx, Provenance>, // LPCWSTR
-    ) -> InterpResult<'tcx, i32> {
+    ) -> InterpResult<'tcx, Scalar<Provenance>> {
         let this = self.eval_context_mut();
         this.assert_target_os("windows", "SetEnvironmentVariableW");
 
@@ -272,7 +274,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 this.deallocate_ptr(var, None, MiriMemoryKind::Runtime.into())?;
                 this.update_environ()?;
             }
-            Ok(1) // return non-zero on success
+            Ok(this.eval_windows("c", "TRUE")?)
         } else {
             let value = this.read_os_str_from_wide_str(value_ptr)?;
             let var_ptr = alloc_env_var_as_wide_str(&name, &value, this)?;
@@ -280,7 +282,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 this.deallocate_ptr(var, None, MiriMemoryKind::Runtime.into())?;
             }
             this.update_environ()?;
-            Ok(1) // return non-zero on success
+            Ok(this.eval_windows("c", "TRUE")?)
         }
     }
 
@@ -347,7 +349,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         &mut self,
         size_op: &OpTy<'tcx, Provenance>, // DWORD
         buf_op: &OpTy<'tcx, Provenance>,  // LPTSTR
-    ) -> InterpResult<'tcx, u32> {
+    ) -> InterpResult<'tcx, Scalar<Provenance>> {
         let this = self.eval_context_mut();
         this.assert_target_os("windows", "GetCurrentDirectoryW");
 
@@ -357,16 +359,18 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         if let IsolatedOp::Reject(reject_with) = this.machine.isolated_op {
             this.reject_in_isolation("`GetCurrentDirectoryW`", reject_with)?;
             this.set_last_error_from_io_error(ErrorKind::PermissionDenied)?;
-            return Ok(0);
+            return Ok(Scalar::from_u32(0));
         }
 
         // If we cannot get the current directory, we return 0
         match env::current_dir() {
             Ok(cwd) =>
-                return Ok(windows_check_buffer_size(this.write_path_to_wide_str(&cwd, buf, size)?)),
+                return Ok(Scalar::from_u32(windows_check_buffer_size(
+                    this.write_path_to_wide_str(&cwd, buf, size)?,
+                ))),
             Err(e) => this.set_last_error_from_io_error(e.kind())?,
         }
-        Ok(0)
+        Ok(Scalar::from_u32(0))
     }
 
     fn chdir(&mut self, path_op: &OpTy<'tcx, Provenance>) -> InterpResult<'tcx, i32> {
@@ -395,7 +399,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn SetCurrentDirectoryW(
         &mut self,
         path_op: &OpTy<'tcx, Provenance>, // LPCTSTR
-    ) -> InterpResult<'tcx, i32> {
+    ) -> InterpResult<'tcx, Scalar<Provenance>> {
         // ^ Returns BOOL (i32 on Windows)
 
         let this = self.eval_context_mut();
@@ -407,14 +411,14 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             this.reject_in_isolation("`SetCurrentDirectoryW`", reject_with)?;
             this.set_last_error_from_io_error(ErrorKind::PermissionDenied)?;
 
-            return Ok(0);
+            return this.eval_windows("c", "FALSE");
         }
 
         match env::set_current_dir(path) {
-            Ok(()) => Ok(1),
+            Ok(()) => this.eval_windows("c", "TRUE"),
             Err(e) => {
                 this.set_last_error_from_io_error(e.kind())?;
-                Ok(0)
+                this.eval_windows("c", "FALSE")
             }
         }
     }
diff --git a/src/tools/miri/src/shims/ffi_support.rs b/src/tools/miri/src/shims/ffi_support.rs
index 0813554e9d24..c5db868cdc7c 100644
--- a/src/tools/miri/src/shims/ffi_support.rs
+++ b/src/tools/miri/src/shims/ffi_support.rs
@@ -183,9 +183,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         // from: https://docs.rs/libloading/0.7.3/src/libloading/os/unix/mod.rs.html#411
         // using the `libc` crate where this interface is public.
         // No `libc::dladdr` on windows.
-        #[cfg(unix)]
         let mut info = std::mem::MaybeUninit::<libc::Dl_info>::uninit();
-        #[cfg(unix)]
         unsafe {
             if libc::dladdr(*func.deref() as *const _, info.as_mut_ptr()) != 0 {
                 if std::ffi::CStr::from_ptr(info.assume_init().dli_fname).to_str().unwrap()
diff --git a/src/tools/miri/src/shims/foreign_items.rs b/src/tools/miri/src/shims/foreign_items.rs
index bb62a2a7ec1b..1b3205aabc99 100644
--- a/src/tools/miri/src/shims/foreign_items.rs
+++ b/src/tools/miri/src/shims/foreign_items.rs
@@ -1,4 +1,4 @@
-use std::{collections::hash_map::Entry, iter};
+use std::{collections::hash_map::Entry, io::Write, iter};
 
 use log::trace;
 
@@ -23,8 +23,6 @@ use rustc_target::{
 
 use super::backtrace::EvalContextExt as _;
 use crate::helpers::{convert::Truncate, target_os_is_unix};
-#[cfg(unix)]
-use crate::shims::ffi_support::EvalContextExt as _;
 use crate::*;
 
 /// Returned by `emulate_foreign_item_by_name`.
@@ -323,7 +321,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                     return Ok(Some(body));
                 }
 
-                this.handle_unsupported(format!("can't call foreign function: {}", link_name))?;
+                this.handle_unsupported(format!("can't call foreign function: {link_name}"))?;
                 return Ok(None);
             }
         }
@@ -372,8 +370,9 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         let this = self.eval_context_mut();
 
         // First deal with any external C functions in linked .so file.
-        #[cfg(unix)]
+        #[cfg(target_os = "linux")]
         if this.machine.external_so_lib.as_ref().is_some() {
+            use crate::shims::ffi_support::EvalContextExt as _;
             // An Ok(false) here means that the function being called was not exported
             // by the specified `.so` file; we should continue and check if it corresponds to
             // a provided shim.
@@ -418,6 +417,23 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         // shim, add it to the corresponding submodule.
         match link_name.as_str() {
             // Miri-specific extern functions
+            "miri_get_alloc_id" => {
+                let [ptr] = this.check_shim(abi, Abi::Rust, link_name, args)?;
+                let ptr = this.read_pointer(ptr)?;
+                let (alloc_id, _, _) = this.ptr_get_alloc_id(ptr).map_err(|_e| {
+                    err_machine_stop!(TerminationInfo::Abort(
+                        format!("pointer passed to miri_get_alloc_id must not be dangling, got {ptr:?}")
+                    ))
+                })?;
+                this.write_scalar(Scalar::from_u64(alloc_id.0.get()), dest)?;
+            }
+            "miri_print_borrow_stacks" => {
+                let [id] = this.check_shim(abi, Abi::Rust, link_name, args)?;
+                let id = this.read_scalar(id)?.to_u64()?;
+                if let Some(id) = std::num::NonZeroU64::new(id) {
+                    this.print_stacks(AllocId(id))?;
+                }
+            }
             "miri_static_root" => {
                 let [ptr] = this.check_shim(abi, Abi::Rust, link_name, args)?;
                 let ptr = this.read_pointer(ptr)?;
@@ -450,6 +466,23 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 this.handle_miri_resolve_frame_names(abi, link_name, args)?;
             }
 
+            // Writes some bytes to the interpreter's stdout/stderr. See the
+            // README for details.
+            "miri_write_to_stdout" | "miri_write_to_stderr" => {
+                let [bytes] = this.check_shim(abi, Abi::Rust, link_name, args)?;
+                let (ptr, len) = this.read_immediate(bytes)?.to_scalar_pair();
+                let ptr = ptr.to_pointer(this)?;
+                let len = len.to_machine_usize(this)?;
+                let msg = this.read_bytes_ptr_strip_provenance(ptr, Size::from_bytes(len))?;
+
+                // Note: we're ignoring errors writing to host stdout/stderr.
+                let _ignore = match link_name.as_str() {
+                    "miri_write_to_stdout" => std::io::stdout().write_all(msg),
+                    "miri_write_to_stderr" => std::io::stderr().write_all(msg),
+                    _ => unreachable!(),
+                };
+            }
+
             // Standard C allocation
             "malloc" => {
                 let [size] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
diff --git a/src/tools/miri/src/shims/intrinsics/mod.rs b/src/tools/miri/src/shims/intrinsics/mod.rs
index e0985ace5be7..6004e2078ad4 100644
--- a/src/tools/miri/src/shims/intrinsics/mod.rs
+++ b/src/tools/miri/src/shims/intrinsics/mod.rs
@@ -11,7 +11,7 @@ use rustc_middle::{
     mir,
     ty::{self, FloatTy, Ty},
 };
-use rustc_target::abi::Integer;
+use rustc_target::abi::{Integer, Size};
 
 use crate::*;
 use atomic::EvalContextExt as _;
@@ -120,6 +120,17 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 this.write_bytes_ptr(ptr, iter::repeat(val_byte).take(byte_count.bytes_usize()))?;
             }
 
+            "ptr_mask" => {
+                let [ptr, mask] = check_arg_count(args)?;
+
+                let ptr = this.read_pointer(ptr)?;
+                let mask = this.read_scalar(mask)?.to_machine_usize(this)?;
+
+                let masked_addr = Size::from_bytes(ptr.addr().bytes() & mask);
+
+                this.write_pointer(Pointer::new(ptr.provenance, masked_addr), dest)?;
+            }
+
             // Floating-point operations
             "fabsf32" => {
                 let [f] = check_arg_count(args)?;
diff --git a/src/tools/miri/src/shims/intrinsics/simd.rs b/src/tools/miri/src/shims/intrinsics/simd.rs
index 163d185f66f3..c1b949b1f799 100644
--- a/src/tools/miri/src/shims/intrinsics/simd.rs
+++ b/src/tools/miri/src/shims/intrinsics/simd.rs
@@ -437,13 +437,13 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                     let val = match (op.layout.ty.kind(), dest.layout.ty.kind()) {
                         // Int-to-(int|float): always safe
                         (ty::Int(_) | ty::Uint(_), ty::Int(_) | ty::Uint(_) | ty::Float(_)) =>
-                            this.misc_cast(&op, dest.layout.ty)?,
+                            this.int_to_int_or_float(&op, dest.layout.ty)?,
                         // Float-to-float: always safe
                         (ty::Float(_), ty::Float(_)) =>
-                            this.misc_cast(&op, dest.layout.ty)?,
+                            this.float_to_float_or_int(&op, dest.layout.ty)?,
                         // Float-to-int in safe mode
                         (ty::Float(_), ty::Int(_) | ty::Uint(_)) if safe_cast =>
-                            this.misc_cast(&op, dest.layout.ty)?,
+                            this.float_to_float_or_int(&op, dest.layout.ty)?,
                         // Float-to-int in unchecked mode
                         (ty::Float(FloatTy::F32), ty::Int(_) | ty::Uint(_)) if !safe_cast =>
                             this.float_to_int_unchecked(op.to_scalar().to_f32()?, dest.layout.ty)?.into(),
diff --git a/src/tools/miri/src/shims/mod.rs b/src/tools/miri/src/shims/mod.rs
index 8cb648e51732..dcb99a276682 100644
--- a/src/tools/miri/src/shims/mod.rs
+++ b/src/tools/miri/src/shims/mod.rs
@@ -1,7 +1,7 @@
 #![warn(clippy::integer_arithmetic)]
 
 mod backtrace;
-#[cfg(unix)]
+#[cfg(target_os = "linux")]
 pub mod ffi_support;
 pub mod foreign_items;
 pub mod intrinsics;
diff --git a/src/tools/miri/src/shims/os_str.rs b/src/tools/miri/src/shims/os_str.rs
index 407dab970ad7..99b3605c6017 100644
--- a/src/tools/miri/src/shims/os_str.rs
+++ b/src/tools/miri/src/shims/os_str.rs
@@ -1,6 +1,5 @@
 use std::borrow::Cow;
 use std::ffi::{OsStr, OsString};
-use std::iter;
 use std::path::{Path, PathBuf};
 
 #[cfg(unix)]
@@ -9,7 +8,6 @@ use std::os::unix::ffi::{OsStrExt, OsStringExt};
 use std::os::windows::ffi::{OsStrExt, OsStringExt};
 
 use rustc_middle::ty::layout::LayoutOf;
-use rustc_target::abi::{Align, Size};
 
 use crate::*;
 
@@ -100,16 +98,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         size: u64,
     ) -> InterpResult<'tcx, (bool, u64)> {
         let bytes = os_str_to_bytes(os_str)?;
-        // If `size` is smaller or equal than `bytes.len()`, writing `bytes` plus the required null
-        // terminator to memory using the `ptr` pointer would cause an out-of-bounds access.
-        let string_length = u64::try_from(bytes.len()).unwrap();
-        let string_length = string_length.checked_add(1).unwrap();
-        if size < string_length {
-            return Ok((false, string_length));
-        }
-        self.eval_context_mut()
-            .write_bytes_ptr(ptr, bytes.iter().copied().chain(iter::once(0u8)))?;
-        Ok((true, string_length))
+        self.eval_context_mut().write_c_str(bytes, ptr, size)
     }
 
     /// Helper function to write an OsStr as a 0x0000-terminated u16-sequence, which is what
@@ -140,25 +129,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         }
 
         let u16_vec = os_str_to_u16vec(os_str)?;
-        // If `size` is smaller or equal than `bytes.len()`, writing `bytes` plus the required
-        // 0x0000 terminator to memory would cause an out-of-bounds access.
-        let string_length = u64::try_from(u16_vec.len()).unwrap();
-        let string_length = string_length.checked_add(1).unwrap();
-        if size < string_length {
-            return Ok((false, string_length));
-        }
-
-        // Store the UTF-16 string.
-        let size2 = Size::from_bytes(2);
-        let this = self.eval_context_mut();
-        let mut alloc = this
-            .get_ptr_alloc_mut(ptr, size2 * string_length, Align::from_bytes(2).unwrap())?
-            .unwrap(); // not a ZST, so we will get a result
-        for (offset, wchar) in u16_vec.into_iter().chain(iter::once(0x0000)).enumerate() {
-            let offset = u64::try_from(offset).unwrap();
-            alloc.write_scalar(alloc_range(size2 * offset, size2), Scalar::from_u16(wchar))?;
-        }
-        Ok((true, string_length))
+        self.eval_context_mut().write_wide_str(&u16_vec, ptr, size)
     }
 
     /// Allocate enough memory to store the given `OsStr` as a null-terminated sequence of bytes.
diff --git a/src/tools/miri/src/shims/time.rs b/src/tools/miri/src/shims/time.rs
index 9f04034e1a12..617f90dfaa59 100644
--- a/src/tools/miri/src/shims/time.rs
+++ b/src/tools/miri/src/shims/time.rs
@@ -119,7 +119,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     fn QueryPerformanceCounter(
         &mut self,
         lpPerformanceCount_op: &OpTy<'tcx, Provenance>,
-    ) -> InterpResult<'tcx, i32> {
+    ) -> InterpResult<'tcx, Scalar<Provenance>> {
         let this = self.eval_context_mut();
 
         this.assert_target_os("windows", "QueryPerformanceCounter");
@@ -134,14 +134,14 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             Scalar::from_i64(qpc),
             &this.deref_operand(lpPerformanceCount_op)?.into(),
         )?;
-        Ok(-1) // return non-zero on success
+        Ok(Scalar::from_i32(-1)) // return non-zero on success
     }
 
     #[allow(non_snake_case)]
     fn QueryPerformanceFrequency(
         &mut self,
         lpFrequency_op: &OpTy<'tcx, Provenance>,
-    ) -> InterpResult<'tcx, i32> {
+    ) -> InterpResult<'tcx, Scalar<Provenance>> {
         let this = self.eval_context_mut();
 
         this.assert_target_os("windows", "QueryPerformanceFrequency");
@@ -155,7 +155,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             Scalar::from_i64(1_000_000_000),
             &this.deref_operand(lpFrequency_op)?.into(),
         )?;
-        Ok(-1) // Return non-zero on success
+        Ok(Scalar::from_i32(-1)) // Return non-zero on success
     }
 
     fn mach_absolute_time(&self) -> InterpResult<'tcx, Scalar<Provenance>> {
diff --git a/src/tools/miri/src/shims/unix/android/dlsym.rs b/src/tools/miri/src/shims/unix/android/dlsym.rs
index 4cb78d4dabdc..b0c9d729c9d9 100644
--- a/src/tools/miri/src/shims/unix/android/dlsym.rs
+++ b/src/tools/miri/src/shims/unix/android/dlsym.rs
@@ -42,7 +42,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                     );
                 }
 
-                let &[ref _sig, ref _func] = check_arg_count(args)?;
+                let [_sig, _func] = check_arg_count(args)?;
                 this.write_null(dest)?;
             }
         }
diff --git a/src/tools/miri/src/shims/unix/foreign_items.rs b/src/tools/miri/src/shims/unix/foreign_items.rs
index c21e0441cacf..44a433df1e9c 100644
--- a/src/tools/miri/src/shims/unix/foreign_items.rs
+++ b/src/tools/miri/src/shims/unix/foreign_items.rs
@@ -452,7 +452,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             "isatty" => {
                 let [fd] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
                 let result = this.isatty(fd)?;
-                this.write_scalar(Scalar::from_i32(result), dest)?;
+                this.write_scalar(result, dest)?;
             }
             "pthread_atfork" => {
                 let [prepare, parent, child] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
diff --git a/src/tools/miri/src/shims/unix/freebsd/foreign_items.rs b/src/tools/miri/src/shims/unix/freebsd/foreign_items.rs
index 70798f981745..d755e5f10bae 100644
--- a/src/tools/miri/src/shims/unix/freebsd/foreign_items.rs
+++ b/src/tools/miri/src/shims/unix/freebsd/foreign_items.rs
@@ -26,8 +26,12 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             "pthread_set_name_np" => {
                 let [thread, name] =
                     this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
-                let res =
-                    this.pthread_setname_np(this.read_scalar(thread)?, this.read_scalar(name)?)?;
+                let max_len = usize::MAX; // freebsd does not seem to have a limit.
+                let res = this.pthread_setname_np(
+                    this.read_scalar(thread)?,
+                    this.read_scalar(name)?,
+                    max_len,
+                )?;
                 this.write_scalar(res, dest)?;
             }
 
diff --git a/src/tools/miri/src/shims/unix/fs.rs b/src/tools/miri/src/shims/unix/fs.rs
index 9713cd9265e5..b152082b4deb 100644
--- a/src/tools/miri/src/shims/unix/fs.rs
+++ b/src/tools/miri/src/shims/unix/fs.rs
@@ -4,7 +4,7 @@ use std::convert::TryInto;
 use std::fs::{
     read_dir, remove_dir, remove_file, rename, DirBuilder, File, FileType, OpenOptions, ReadDir,
 };
-use std::io::{self, ErrorKind, Read, Seek, SeekFrom, Write};
+use std::io::{self, ErrorKind, IsTerminal, Read, Seek, SeekFrom, Write};
 use std::path::{Path, PathBuf};
 use std::time::SystemTime;
 
@@ -65,6 +65,8 @@ trait FileDescriptor: std::fmt::Debug {
 
     fn dup(&mut self) -> io::Result<Box<dyn FileDescriptor>>;
 
+    fn is_tty(&self) -> bool;
+
     #[cfg(unix)]
     fn as_unix_host_fd(&self) -> Option<i32> {
         None
@@ -143,6 +145,10 @@ impl FileDescriptor for FileHandle {
         use std::os::unix::io::AsRawFd;
         Some(self.file.as_raw_fd())
     }
+
+    fn is_tty(&self) -> bool {
+        self.file.is_terminal()
+    }
 }
 
 impl FileDescriptor for io::Stdin {
@@ -170,6 +176,10 @@ impl FileDescriptor for io::Stdin {
     fn as_unix_host_fd(&self) -> Option<i32> {
         Some(libc::STDIN_FILENO)
     }
+
+    fn is_tty(&self) -> bool {
+        self.is_terminal()
+    }
 }
 
 impl FileDescriptor for io::Stdout {
@@ -202,6 +212,10 @@ impl FileDescriptor for io::Stdout {
     fn as_unix_host_fd(&self) -> Option<i32> {
         Some(libc::STDOUT_FILENO)
     }
+
+    fn is_tty(&self) -> bool {
+        self.is_terminal()
+    }
 }
 
 impl FileDescriptor for io::Stderr {
@@ -227,12 +241,16 @@ impl FileDescriptor for io::Stderr {
     fn as_unix_host_fd(&self) -> Option<i32> {
         Some(libc::STDERR_FILENO)
     }
+
+    fn is_tty(&self) -> bool {
+        self.is_terminal()
+    }
 }
 
 #[derive(Debug)]
-struct DummyOutput;
+struct NullOutput;
 
-impl FileDescriptor for DummyOutput {
+impl FileDescriptor for NullOutput {
     fn name(&self) -> &'static str {
         "stderr and stdout"
     }
@@ -247,7 +265,11 @@ impl FileDescriptor for DummyOutput {
     }
 
     fn dup(&mut self) -> io::Result<Box<dyn FileDescriptor>> {
-        Ok(Box::new(DummyOutput))
+        Ok(Box::new(NullOutput))
+    }
+
+    fn is_tty(&self) -> bool {
+        false
     }
 }
 
@@ -267,8 +289,8 @@ impl FileHandler {
         let mut handles: BTreeMap<_, Box<dyn FileDescriptor>> = BTreeMap::new();
         handles.insert(0i32, Box::new(io::stdin()));
         if mute_stdout_stderr {
-            handles.insert(1i32, Box::new(DummyOutput));
-            handles.insert(2i32, Box::new(DummyOutput));
+            handles.insert(1i32, Box::new(NullOutput));
+            handles.insert(2i32, Box::new(NullOutput));
         } else {
             handles.insert(1i32, Box::new(io::stdout()));
             handles.insert(2i32, Box::new(io::stderr()));
@@ -599,7 +621,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             return Ok(-1);
         }
 
-        let fd = options.open(&path).map(|file| {
+        let fd = options.open(path).map(|file| {
             let fh = &mut this.machine.file_handler;
             fh.insert_fd(Box::new(FileHandle { file, writable }))
         });
@@ -1073,7 +1095,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 mask |= this.eval_libc("STATX_ATIME")?.to_u32()?;
                 InterpResult::Ok(tup)
             })
-            .unwrap_or(Ok((0, 0)))?;
+            .unwrap_or_else(|| Ok((0, 0)))?;
 
         let (created_sec, created_nsec) = metadata
             .created
@@ -1081,7 +1103,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 mask |= this.eval_libc("STATX_BTIME")?.to_u32()?;
                 InterpResult::Ok(tup)
             })
-            .unwrap_or(Ok((0, 0)))?;
+            .unwrap_or_else(|| Ok((0, 0)))?;
 
         let (modified_sec, modified_nsec) = metadata
             .modified
@@ -1089,7 +1111,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 mask |= this.eval_libc("STATX_MTIME")?.to_u32()?;
                 InterpResult::Ok(tup)
             })
-            .unwrap_or(Ok((0, 0)))?;
+            .unwrap_or_else(|| Ok((0, 0)))?;
 
         // Now we write everything to `statxbuf`. We write a zero for the unavailable fields.
         this.write_int_fields_named(
@@ -1662,35 +1684,23 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     }
 
     #[cfg_attr(not(unix), allow(unused))]
-    fn isatty(&mut self, miri_fd: &OpTy<'tcx, Provenance>) -> InterpResult<'tcx, i32> {
+    fn isatty(
+        &mut self,
+        miri_fd: &OpTy<'tcx, Provenance>,
+    ) -> InterpResult<'tcx, Scalar<Provenance>> {
         let this = self.eval_context_mut();
-        #[cfg(unix)]
+        // "returns 1 if fd is an open file descriptor referring to a terminal;
+        // otherwise 0 is returned, and errno is set to indicate the error"
         if matches!(this.machine.isolated_op, IsolatedOp::Allow) {
-            let miri_fd = this.read_scalar(miri_fd)?.to_i32()?;
-            if let Some(host_fd) =
-                this.machine.file_handler.handles.get(&miri_fd).and_then(|fd| fd.as_unix_host_fd())
-            {
-                // "returns 1 if fd is an open file descriptor referring to a terminal;
-                // otherwise 0 is returned, and errno is set to indicate the error"
-                // SAFETY: isatty has no preconditions
-                let is_tty = unsafe { libc::isatty(host_fd) };
-                if is_tty == 0 {
-                    let errno = std::io::Error::last_os_error()
-                        .raw_os_error()
-                        .map(Scalar::from_i32)
-                        .unwrap();
-                    this.set_last_error(errno)?;
-                }
-                return Ok(is_tty);
+            let fd = this.read_scalar(miri_fd)?.to_i32()?;
+            if this.machine.file_handler.handles.get(&fd).map(|fd| fd.is_tty()) == Some(true) {
+                return Ok(Scalar::from_i32(1));
             }
         }
-        // We are attemping to use a Unix interface on a non-Unix platform, or we are on a Unix
-        // platform and the passed file descriptor is not open, or isolation is enabled
-        // FIXME: It should be possible to emulate this at least on Windows by using
-        // GetConsoleMode.
+        // Fallback when the FD was not found or isolation is enabled.
         let enotty = this.eval_libc("ENOTTY")?;
         this.set_last_error(enotty)?;
-        Ok(0)
+        Ok(Scalar::from_i32(0))
     }
 
     fn realpath(
@@ -1852,7 +1862,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
 
             let possibly_unique = std::env::temp_dir().join::<PathBuf>(p.into());
 
-            let file = fopts.open(&possibly_unique);
+            let file = fopts.open(possibly_unique);
 
             match file {
                 Ok(f) => {
diff --git a/src/tools/miri/src/shims/unix/linux/foreign_items.rs b/src/tools/miri/src/shims/unix/linux/foreign_items.rs
index 5d000f9d121d..2b53152688bb 100644
--- a/src/tools/miri/src/shims/unix/linux/foreign_items.rs
+++ b/src/tools/miri/src/shims/unix/linux/foreign_items.rs
@@ -68,8 +68,22 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             "pthread_setname_np" => {
                 let [thread, name] =
                     this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
-                let res =
-                    this.pthread_setname_np(this.read_scalar(thread)?, this.read_scalar(name)?)?;
+                let max_len = 16;
+                let res = this.pthread_setname_np(
+                    this.read_scalar(thread)?,
+                    this.read_scalar(name)?,
+                    max_len,
+                )?;
+                this.write_scalar(res, dest)?;
+            }
+            "pthread_getname_np" => {
+                let [thread, name, len] =
+                    this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
+                let res = this.pthread_getname_np(
+                    this.read_scalar(thread)?,
+                    this.read_scalar(name)?,
+                    this.read_scalar(len)?,
+                )?;
                 this.write_scalar(res, dest)?;
             }
 
@@ -126,7 +140,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                         futex(this, &args[1..], dest)?;
                     }
                     id => {
-                        this.handle_unsupported(format!("can't execute syscall with ID {}", id))?;
+                        this.handle_unsupported(format!("can't execute syscall with ID {id}"))?;
                         return Ok(EmulateByNameResult::AlreadyJumped);
                     }
                 }
diff --git a/src/tools/miri/src/shims/unix/linux/sync.rs b/src/tools/miri/src/shims/unix/linux/sync.rs
index 5762ee27b84a..292b9d2e7a17 100644
--- a/src/tools/miri/src/shims/unix/linux/sync.rs
+++ b/src/tools/miri/src/shims/unix/linux/sync.rs
@@ -1,7 +1,7 @@
+use std::time::SystemTime;
+
 use crate::concurrency::thread::{MachineCallback, Time};
 use crate::*;
-use rustc_target::abi::{Align, Size};
-use std::time::SystemTime;
 
 /// Implementation of the SYS_futex syscall.
 /// `args` is the arguments *after* the syscall number.
@@ -28,13 +28,14 @@ pub fn futex<'tcx>(
     // The first three arguments (after the syscall number itself) are the same to all futex operations:
     //     (int *addr, int op, int val).
     // We checked above that these definitely exist.
-    let addr = this.read_immediate(&args[0])?;
+    let addr = this.read_pointer(&args[0])?;
     let op = this.read_scalar(&args[1])?.to_i32()?;
     let val = this.read_scalar(&args[2])?.to_i32()?;
 
     let thread = this.get_active_thread();
-    let addr_scalar = addr.to_scalar();
-    let addr_usize = addr_scalar.to_machine_usize(this)?;
+    // This is a vararg function so we have to bring our own type for this pointer.
+    let addr = MPlaceTy::from_aligned_ptr(addr, this.machine.layouts.i32);
+    let addr_usize = addr.ptr.addr().bytes();
 
     let futex_private = this.eval_libc_i32("FUTEX_PRIVATE_FLAG")?;
     let futex_wait = this.eval_libc_i32("FUTEX_WAIT")?;
@@ -89,9 +90,11 @@ pub fn futex<'tcx>(
             let timeout_time = if this.ptr_is_null(timeout.ptr)? {
                 None
             } else {
-                this.check_no_isolation(
-                    "`futex` syscall with `op=FUTEX_WAIT` and non-null timeout",
-                )?;
+                if op & futex_realtime != 0 {
+                    this.check_no_isolation(
+                        "`futex` syscall with `op=FUTEX_WAIT` and non-null timeout with `FUTEX_CLOCK_REALTIME`",
+                    )?;
+                }
                 let duration = match this.read_timespec(&timeout)? {
                     Some(duration) => duration,
                     None => {
@@ -117,15 +120,6 @@ pub fn futex<'tcx>(
                     }
                 })
             };
-            // Check the pointer for alignment and validity.
-            // The API requires `addr` to be a 4-byte aligned pointer, and will
-            // use the 4 bytes at the given address as an (atomic) i32.
-            this.check_ptr_access_align(
-                addr_scalar.to_pointer(this)?,
-                Size::from_bytes(4),
-                Align::from_bytes(4).unwrap(),
-                CheckInAllocMsg::MemoryAccessTest,
-            )?;
             // There may be a concurrent thread changing the value of addr
             // and then invoking the FUTEX_WAKE syscall. It is critical that the
             // effects of this and the other thread are correctly observed,
@@ -172,14 +166,7 @@ pub fn futex<'tcx>(
             this.atomic_fence(AtomicFenceOrd::SeqCst)?;
             // Read an `i32` through the pointer, regardless of any wrapper types.
             // It's not uncommon for `addr` to be passed as another type than `*mut i32`, such as `*const AtomicI32`.
-            let futex_val = this
-                .read_scalar_at_offset_atomic(
-                    &addr.into(),
-                    0,
-                    this.machine.layouts.i32,
-                    AtomicReadOrd::Relaxed,
-                )?
-                .to_i32()?;
+            let futex_val = this.read_scalar_atomic(&addr, AtomicReadOrd::Relaxed)?.to_i32()?;
             if val == futex_val {
                 // The value still matches, so we block the thread make it wait for FUTEX_WAKE.
                 this.block_thread(thread);
@@ -214,11 +201,10 @@ pub fn futex<'tcx>(
                         }
                     }
 
-                    let dest = dest.clone();
                     this.register_timeout_callback(
                         thread,
                         timeout_time,
-                        Box::new(Callback { thread, addr_usize, dest }),
+                        Box::new(Callback { thread, addr_usize, dest: dest.clone() }),
                     );
                 }
             } else {
diff --git a/src/tools/miri/src/shims/unix/macos/foreign_items.rs b/src/tools/miri/src/shims/unix/macos/foreign_items.rs
index 38d791fba98a..221dc39697f9 100644
--- a/src/tools/miri/src/shims/unix/macos/foreign_items.rs
+++ b/src/tools/miri/src/shims/unix/macos/foreign_items.rs
@@ -176,7 +176,25 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             "pthread_setname_np" => {
                 let [name] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
                 let thread = this.pthread_self()?;
-                this.pthread_setname_np(thread, this.read_scalar(name)?)?;
+                let max_len = this.eval_libc("MAXTHREADNAMESIZE")?.to_machine_usize(this)?;
+                let res = this.pthread_setname_np(
+                    thread,
+                    this.read_scalar(name)?,
+                    max_len.try_into().unwrap(),
+                )?;
+                // Contrary to the manpage, `pthread_setname_np` on macOS still
+                // returns an integer indicating success.
+                this.write_scalar(res, dest)?;
+            }
+            "pthread_getname_np" => {
+                let [thread, name, len] =
+                    this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
+                let res = this.pthread_getname_np(
+                    this.read_scalar(thread)?,
+                    this.read_scalar(name)?,
+                    this.read_scalar(len)?,
+                )?;
+                this.write_scalar(res, dest)?;
             }
 
             // Incomplete shims that we "stub out" just to get pre-main initialization code to work.
diff --git a/src/tools/miri/src/shims/unix/sync.rs b/src/tools/miri/src/shims/unix/sync.rs
index 5aafe76ade1d..a7275646847e 100644
--- a/src/tools/miri/src/shims/unix/sync.rs
+++ b/src/tools/miri/src/shims/unix/sync.rs
@@ -3,6 +3,7 @@ use std::time::SystemTime;
 use rustc_hir::LangItem;
 use rustc_middle::ty::{layout::TyAndLayout, query::TyCtxtAt, Ty};
 
+use crate::concurrency::sync::CondvarLock;
 use crate::concurrency::thread::{MachineCallback, Time};
 use crate::*;
 
@@ -19,6 +20,10 @@ use crate::*;
 /// in `pthread_mutexattr_settype` function.
 const PTHREAD_MUTEX_NORMAL_FLAG: i32 = 0x8000000;
 
+const MUTEX_ID_OFFSET: u64 = 4;
+const RWLOCK_ID_OFFSET: u64 = 4;
+const CONDVAR_ID_OFFSET: u64 = 4;
+
 fn is_mutex_kind_default<'mir, 'tcx: 'mir>(
     ecx: &mut MiriInterpCx<'mir, 'tcx>,
     kind: Scalar<Provenance>,
@@ -108,33 +113,6 @@ fn mutex_set_id<'mir, 'tcx: 'mir>(
     )
 }
 
-fn mutex_get_or_create_id<'mir, 'tcx: 'mir>(
-    ecx: &mut MiriInterpCx<'mir, 'tcx>,
-    mutex_op: &OpTy<'tcx, Provenance>,
-) -> InterpResult<'tcx, MutexId> {
-    let value_place = ecx.deref_operand_and_offset(mutex_op, 4, ecx.machine.layouts.u32)?;
-
-    ecx.mutex_get_or_create(|ecx, next_id| {
-        let (old, success) = ecx
-            .atomic_compare_exchange_scalar(
-                &value_place,
-                &ImmTy::from_uint(0u32, ecx.machine.layouts.u32),
-                next_id.to_u32_scalar(),
-                AtomicRwOrd::Relaxed,
-                AtomicReadOrd::Relaxed,
-                false,
-            )?
-            .to_scalar_pair();
-
-        Ok(if success.to_bool().expect("compare_exchange's second return value is a bool") {
-            // Caller of the closure needs to allocate next_id
-            None
-        } else {
-            Some(MutexId::from_u32(old.to_u32().expect("layout is u32")))
-        })
-    })
-}
-
 // pthread_rwlock_t is between 32 and 56 bytes, depending on the platform.
 
 // Our chosen memory layout for the emulated rwlock (does not have to match the platform layout!):
@@ -149,33 +127,6 @@ fn rwlock_get_id<'mir, 'tcx: 'mir>(
     ecx.read_scalar_at_offset_atomic(rwlock_op, 4, ecx.machine.layouts.u32, AtomicReadOrd::Relaxed)
 }
 
-fn rwlock_get_or_create_id<'mir, 'tcx: 'mir>(
-    ecx: &mut MiriInterpCx<'mir, 'tcx>,
-    rwlock_op: &OpTy<'tcx, Provenance>,
-) -> InterpResult<'tcx, RwLockId> {
-    let value_place = ecx.deref_operand_and_offset(rwlock_op, 4, ecx.machine.layouts.u32)?;
-
-    ecx.rwlock_get_or_create(|ecx, next_id| {
-        let (old, success) = ecx
-            .atomic_compare_exchange_scalar(
-                &value_place,
-                &ImmTy::from_uint(0u32, ecx.machine.layouts.u32),
-                next_id.to_u32_scalar(),
-                AtomicRwOrd::Relaxed,
-                AtomicReadOrd::Relaxed,
-                false,
-            )?
-            .to_scalar_pair();
-
-        Ok(if success.to_bool().expect("compare_exchange's second return value is a bool") {
-            // Caller of the closure needs to allocate next_id
-            None
-        } else {
-            Some(RwLockId::from_u32(old.to_u32().expect("layout is u32")))
-        })
-    })
-}
-
 // pthread_condattr_t
 
 // Our chosen memory layout for emulation (does not have to match the platform layout!):
@@ -232,33 +183,6 @@ fn cond_set_id<'mir, 'tcx: 'mir>(
     )
 }
 
-fn cond_get_or_create_id<'mir, 'tcx: 'mir>(
-    ecx: &mut MiriInterpCx<'mir, 'tcx>,
-    cond_op: &OpTy<'tcx, Provenance>,
-) -> InterpResult<'tcx, CondvarId> {
-    let value_place = ecx.deref_operand_and_offset(cond_op, 4, ecx.machine.layouts.u32)?;
-
-    ecx.condvar_get_or_create(|ecx, next_id| {
-        let (old, success) = ecx
-            .atomic_compare_exchange_scalar(
-                &value_place,
-                &ImmTy::from_uint(0u32, ecx.machine.layouts.u32),
-                next_id.to_u32_scalar(),
-                AtomicRwOrd::Relaxed,
-                AtomicReadOrd::Relaxed,
-                false,
-            )?
-            .to_scalar_pair();
-
-        Ok(if success.to_bool().expect("compare_exchange's second return value is a bool") {
-            // Caller of the closure needs to allocate next_id
-            None
-        } else {
-            Some(CondvarId::from_u32(old.to_u32().expect("layout is u32")))
-        })
-    })
-}
-
 fn cond_get_clock_id<'mir, 'tcx: 'mir>(
     ecx: &MiriInterpCx<'mir, 'tcx>,
     cond_op: &OpTy<'tcx, Provenance>,
@@ -435,7 +359,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         let this = self.eval_context_mut();
 
         let kind = mutex_get_kind(this, mutex_op)?;
-        let id = mutex_get_or_create_id(this, mutex_op)?;
+        let id = this.mutex_get_or_create_id(mutex_op, MUTEX_ID_OFFSET)?;
         let active_thread = this.get_active_thread();
 
         if this.mutex_is_locked(id) {
@@ -475,7 +399,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         let this = self.eval_context_mut();
 
         let kind = mutex_get_kind(this, mutex_op)?;
-        let id = mutex_get_or_create_id(this, mutex_op)?;
+        let id = this.mutex_get_or_create_id(mutex_op, MUTEX_ID_OFFSET)?;
         let active_thread = this.get_active_thread();
 
         if this.mutex_is_locked(id) {
@@ -511,7 +435,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         let this = self.eval_context_mut();
 
         let kind = mutex_get_kind(this, mutex_op)?;
-        let id = mutex_get_or_create_id(this, mutex_op)?;
+        let id = this.mutex_get_or_create_id(mutex_op, MUTEX_ID_OFFSET)?;
         let active_thread = this.get_active_thread();
 
         if let Some(_old_locked_count) = this.mutex_unlock(id, active_thread) {
@@ -545,7 +469,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     ) -> InterpResult<'tcx, i32> {
         let this = self.eval_context_mut();
 
-        let id = mutex_get_or_create_id(this, mutex_op)?;
+        let id = this.mutex_get_or_create_id(mutex_op, MUTEX_ID_OFFSET)?;
 
         if this.mutex_is_locked(id) {
             throw_ub_format!("destroyed a locked mutex");
@@ -568,7 +492,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     ) -> InterpResult<'tcx, i32> {
         let this = self.eval_context_mut();
 
-        let id = rwlock_get_or_create_id(this, rwlock_op)?;
+        let id = this.rwlock_get_or_create_id(rwlock_op, RWLOCK_ID_OFFSET)?;
         let active_thread = this.get_active_thread();
 
         if this.rwlock_is_write_locked(id) {
@@ -586,7 +510,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     ) -> InterpResult<'tcx, i32> {
         let this = self.eval_context_mut();
 
-        let id = rwlock_get_or_create_id(this, rwlock_op)?;
+        let id = this.rwlock_get_or_create_id(rwlock_op, RWLOCK_ID_OFFSET)?;
         let active_thread = this.get_active_thread();
 
         if this.rwlock_is_write_locked(id) {
@@ -603,7 +527,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     ) -> InterpResult<'tcx, i32> {
         let this = self.eval_context_mut();
 
-        let id = rwlock_get_or_create_id(this, rwlock_op)?;
+        let id = this.rwlock_get_or_create_id(rwlock_op, RWLOCK_ID_OFFSET)?;
         let active_thread = this.get_active_thread();
 
         if this.rwlock_is_locked(id) {
@@ -633,7 +557,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     ) -> InterpResult<'tcx, i32> {
         let this = self.eval_context_mut();
 
-        let id = rwlock_get_or_create_id(this, rwlock_op)?;
+        let id = this.rwlock_get_or_create_id(rwlock_op, RWLOCK_ID_OFFSET)?;
         let active_thread = this.get_active_thread();
 
         if this.rwlock_is_locked(id) {
@@ -650,7 +574,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     ) -> InterpResult<'tcx, i32> {
         let this = self.eval_context_mut();
 
-        let id = rwlock_get_or_create_id(this, rwlock_op)?;
+        let id = this.rwlock_get_or_create_id(rwlock_op, RWLOCK_ID_OFFSET)?;
         let active_thread = this.get_active_thread();
 
         #[allow(clippy::if_same_then_else)]
@@ -669,7 +593,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     ) -> InterpResult<'tcx, i32> {
         let this = self.eval_context_mut();
 
-        let id = rwlock_get_or_create_id(this, rwlock_op)?;
+        let id = this.rwlock_get_or_create_id(rwlock_op, RWLOCK_ID_OFFSET)?;
 
         if this.rwlock_is_locked(id) {
             throw_ub_format!("destroyed a locked rwlock");
@@ -772,9 +696,13 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
 
     fn pthread_cond_signal(&mut self, cond_op: &OpTy<'tcx, Provenance>) -> InterpResult<'tcx, i32> {
         let this = self.eval_context_mut();
-        let id = cond_get_or_create_id(this, cond_op)?;
-        if let Some((thread, mutex)) = this.condvar_signal(id) {
-            post_cond_signal(this, thread, mutex)?;
+        let id = this.condvar_get_or_create_id(cond_op, CONDVAR_ID_OFFSET)?;
+        if let Some((thread, lock)) = this.condvar_signal(id) {
+            if let CondvarLock::Mutex(mutex) = lock {
+                post_cond_signal(this, thread, mutex)?;
+            } else {
+                panic!("condvar should not have an rwlock on unix");
+            }
         }
 
         Ok(0)
@@ -785,10 +713,14 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         cond_op: &OpTy<'tcx, Provenance>,
     ) -> InterpResult<'tcx, i32> {
         let this = self.eval_context_mut();
-        let id = cond_get_or_create_id(this, cond_op)?;
+        let id = this.condvar_get_or_create_id(cond_op, CONDVAR_ID_OFFSET)?;
 
-        while let Some((thread, mutex)) = this.condvar_signal(id) {
-            post_cond_signal(this, thread, mutex)?;
+        while let Some((thread, lock)) = this.condvar_signal(id) {
+            if let CondvarLock::Mutex(mutex) = lock {
+                post_cond_signal(this, thread, mutex)?;
+            } else {
+                panic!("condvar should not have an rwlock on unix");
+            }
         }
 
         Ok(0)
@@ -801,12 +733,12 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     ) -> InterpResult<'tcx, i32> {
         let this = self.eval_context_mut();
 
-        let id = cond_get_or_create_id(this, cond_op)?;
-        let mutex_id = mutex_get_or_create_id(this, mutex_op)?;
+        let id = this.condvar_get_or_create_id(cond_op, CONDVAR_ID_OFFSET)?;
+        let mutex_id = this.mutex_get_or_create_id(mutex_op, MUTEX_ID_OFFSET)?;
         let active_thread = this.get_active_thread();
 
         release_cond_mutex_and_block(this, active_thread, mutex_id)?;
-        this.condvar_wait(id, active_thread, mutex_id);
+        this.condvar_wait(id, active_thread, CondvarLock::Mutex(mutex_id));
 
         Ok(0)
     }
@@ -820,10 +752,8 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     ) -> InterpResult<'tcx> {
         let this = self.eval_context_mut();
 
-        this.check_no_isolation("`pthread_cond_timedwait`")?;
-
-        let id = cond_get_or_create_id(this, cond_op)?;
-        let mutex_id = mutex_get_or_create_id(this, mutex_op)?;
+        let id = this.condvar_get_or_create_id(cond_op, CONDVAR_ID_OFFSET)?;
+        let mutex_id = this.mutex_get_or_create_id(mutex_op, MUTEX_ID_OFFSET)?;
         let active_thread = this.get_active_thread();
 
         // Extract the timeout.
@@ -838,6 +768,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         };
 
         let timeout_time = if clock_id == this.eval_libc_i32("CLOCK_REALTIME")? {
+            this.check_no_isolation("`pthread_cond_timedwait` with `CLOCK_REALTIME`")?;
             Time::RealTime(SystemTime::UNIX_EPOCH.checked_add(duration).unwrap())
         } else if clock_id == this.eval_libc_i32("CLOCK_MONOTONIC")? {
             Time::Monotonic(this.machine.clock.anchor().checked_add(duration).unwrap())
@@ -846,7 +777,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         };
 
         release_cond_mutex_and_block(this, active_thread, mutex_id)?;
-        this.condvar_wait(id, active_thread, mutex_id);
+        this.condvar_wait(id, active_thread, CondvarLock::Mutex(mutex_id));
 
         // We return success for now and override it in the timeout callback.
         this.write_scalar(Scalar::from_i32(0), dest)?;
@@ -899,7 +830,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
     ) -> InterpResult<'tcx, i32> {
         let this = self.eval_context_mut();
 
-        let id = cond_get_or_create_id(this, cond_op)?;
+        let id = this.condvar_get_or_create_id(cond_op, CONDVAR_ID_OFFSET)?;
         if this.condvar_is_awaited(id) {
             throw_ub_format!("destroying an awaited conditional variable");
         }
diff --git a/src/tools/miri/src/shims/unix/thread.rs b/src/tools/miri/src/shims/unix/thread.rs
index 59474d8d10ad..b43682710bbe 100644
--- a/src/tools/miri/src/shims/unix/thread.rs
+++ b/src/tools/miri/src/shims/unix/thread.rs
@@ -67,10 +67,13 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         Ok(Scalar::from_machine_usize(thread_id.into(), this))
     }
 
+    /// Set the name of the current thread. `max_name_len` is the maximal length of the name
+    /// including the null terminator.
     fn pthread_setname_np(
         &mut self,
         thread: Scalar<Provenance>,
         name: Scalar<Provenance>,
+        max_name_len: usize,
     ) -> InterpResult<'tcx, Scalar<Provenance>> {
         let this = self.eval_context_mut();
 
@@ -78,11 +81,35 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         let name = name.to_pointer(this)?;
 
         let name = this.read_c_str(name)?.to_owned();
+
+        // Comparing with `>=` to account for null terminator.
+        if name.len() >= max_name_len {
+            return this.eval_libc("ERANGE");
+        }
+
         this.set_thread_name(thread, name);
 
         Ok(Scalar::from_u32(0))
     }
 
+    fn pthread_getname_np(
+        &mut self,
+        thread: Scalar<Provenance>,
+        name_out: Scalar<Provenance>,
+        len: Scalar<Provenance>,
+    ) -> InterpResult<'tcx, Scalar<Provenance>> {
+        let this = self.eval_context_mut();
+
+        let thread = ThreadId::try_from(thread.to_machine_usize(this)?).unwrap();
+        let name_out = name_out.to_pointer(this)?;
+        let len = len.to_machine_usize(this)?;
+
+        let name = this.get_thread_name(thread).to_owned();
+        let (success, _written) = this.write_c_str(&name, name_out, len)?;
+
+        if success { Ok(Scalar::from_u32(0)) } else { this.eval_libc("ERANGE") }
+    }
+
     fn sched_yield(&mut self) -> InterpResult<'tcx, i32> {
         let this = self.eval_context_mut();
 
diff --git a/src/tools/miri/src/shims/windows/dlsym.rs b/src/tools/miri/src/shims/windows/dlsym.rs
index 41b9473f81fe..4b2a90723c79 100644
--- a/src/tools/miri/src/shims/windows/dlsym.rs
+++ b/src/tools/miri/src/shims/windows/dlsym.rs
@@ -6,12 +6,15 @@ use log::trace;
 
 use crate::helpers::check_arg_count;
 use crate::shims::windows::handle::{EvalContextExt as _, Handle, PseudoHandle};
+use crate::shims::windows::sync::EvalContextExt as _;
 use crate::*;
 
 #[derive(Debug, Copy, Clone)]
 pub enum Dlsym {
     NtWriteFile,
     SetThreadDescription,
+    WaitOnAddress,
+    WakeByAddressSingle,
 }
 
 impl Dlsym {
@@ -22,6 +25,8 @@ impl Dlsym {
             "GetSystemTimePreciseAsFileTime" => None,
             "NtWriteFile" => Some(Dlsym::NtWriteFile),
             "SetThreadDescription" => Some(Dlsym::SetThreadDescription),
+            "WaitOnAddress" => Some(Dlsym::WaitOnAddress),
+            "WakeByAddressSingle" => Some(Dlsym::WakeByAddressSingle),
             _ => throw_unsup_format!("unsupported Windows dlsym: {}", name),
         })
     }
@@ -127,6 +132,16 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
 
                 this.write_null(dest)?;
             }
+            Dlsym::WaitOnAddress => {
+                let [ptr_op, compare_op, size_op, timeout_op] = check_arg_count(args)?;
+
+                this.WaitOnAddress(ptr_op, compare_op, size_op, timeout_op, dest)?;
+            }
+            Dlsym::WakeByAddressSingle => {
+                let [ptr_op] = check_arg_count(args)?;
+
+                this.WakeByAddressSingle(ptr_op)?;
+            }
         }
 
         trace!("{:?}", this.dump_place(**dest));
diff --git a/src/tools/miri/src/shims/windows/foreign_items.rs b/src/tools/miri/src/shims/windows/foreign_items.rs
index c5f0de4307c3..e16749c986b1 100644
--- a/src/tools/miri/src/shims/windows/foreign_items.rs
+++ b/src/tools/miri/src/shims/windows/foreign_items.rs
@@ -37,13 +37,13 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 let [name, buf, size] =
                     this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
                 let result = this.GetEnvironmentVariableW(name, buf, size)?;
-                this.write_scalar(Scalar::from_u32(result), dest)?;
+                this.write_scalar(result, dest)?;
             }
             "SetEnvironmentVariableW" => {
                 let [name, value] =
                     this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
                 let result = this.SetEnvironmentVariableW(name, value)?;
-                this.write_scalar(Scalar::from_i32(result), dest)?;
+                this.write_scalar(result, dest)?;
             }
             "GetEnvironmentStringsW" => {
                 let [] = this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
@@ -54,19 +54,19 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 let [env_block] =
                     this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
                 let result = this.FreeEnvironmentStringsW(env_block)?;
-                this.write_scalar(Scalar::from_i32(result), dest)?;
+                this.write_scalar(result, dest)?;
             }
             "GetCurrentDirectoryW" => {
                 let [size, buf] =
                     this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
                 let result = this.GetCurrentDirectoryW(size, buf)?;
-                this.write_scalar(Scalar::from_u32(result), dest)?;
+                this.write_scalar(result, dest)?;
             }
             "SetCurrentDirectoryW" => {
                 let [path] =
                     this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
                 let result = this.SetCurrentDirectoryW(path)?;
-                this.write_scalar(Scalar::from_i32(result), dest)?;
+                this.write_scalar(result, dest)?;
             }
 
             // Allocation
@@ -218,14 +218,14 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 let [lpPerformanceCount] =
                     this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
                 let result = this.QueryPerformanceCounter(lpPerformanceCount)?;
-                this.write_scalar(Scalar::from_i32(result), dest)?;
+                this.write_scalar(result, dest)?;
             }
             "QueryPerformanceFrequency" => {
                 #[allow(non_snake_case)]
                 let [lpFrequency] =
                     this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
                 let result = this.QueryPerformanceFrequency(lpFrequency)?;
-                this.write_scalar(Scalar::from_i32(result), dest)?;
+                this.write_scalar(result, dest)?;
             }
             "Sleep" => {
                 let [timeout] =
@@ -246,7 +246,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             "TryAcquireSRWLockExclusive" => {
                 let [ptr] = this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
                 let ret = this.TryAcquireSRWLockExclusive(ptr)?;
-                this.write_scalar(Scalar::from_u8(ret), dest)?;
+                this.write_scalar(ret, dest)?;
             }
             "AcquireSRWLockShared" => {
                 let [ptr] = this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
@@ -259,7 +259,38 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             "TryAcquireSRWLockShared" => {
                 let [ptr] = this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
                 let ret = this.TryAcquireSRWLockShared(ptr)?;
-                this.write_scalar(Scalar::from_u8(ret), dest)?;
+                this.write_scalar(ret, dest)?;
+            }
+            "InitOnceBeginInitialize" => {
+                let [ptr, flags, pending, context] =
+                    this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
+                let result = this.InitOnceBeginInitialize(ptr, flags, pending, context)?;
+                this.write_scalar(result, dest)?;
+            }
+            "InitOnceComplete" => {
+                let [ptr, flags, context] =
+                    this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
+                let result = this.InitOnceComplete(ptr, flags, context)?;
+                this.write_scalar(result, dest)?;
+            }
+            "SleepConditionVariableSRW" => {
+                let [condvar, lock, timeout, flags] =
+                    this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
+
+                let result = this.SleepConditionVariableSRW(condvar, lock, timeout, flags, dest)?;
+                this.write_scalar(result, dest)?;
+            }
+            "WakeConditionVariable" => {
+                let [condvar] =
+                    this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
+
+                this.WakeConditionVariable(condvar)?;
+            }
+            "WakeAllConditionVariable" => {
+                let [condvar] =
+                    this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
+
+                this.WakeAllConditionVariable(condvar)?;
             }
 
             // Dynamic symbol loading
@@ -331,16 +362,6 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 // FIXME: we should set last_error, but to what?
                 this.write_null(dest)?;
             }
-            "GetConsoleMode" => {
-                // Windows "isatty" (in libtest) needs this, so we fake it.
-                let [console, mode] =
-                    this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
-                this.read_scalar(console)?.to_machine_isize(this)?;
-                this.deref_operand(mode)?;
-                // Indicate an error.
-                // FIXME: we should set last_error, but to what?
-                this.write_null(dest)?;
-            }
             "GetStdHandle" => {
                 let [which] =
                     this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
@@ -392,14 +413,14 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 let [] = this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
                 // Just fake a HANDLE
                 // It's fine to not use the Handle type here because its a stub
-                this.write_scalar(Scalar::from_machine_isize(1, this), dest)?;
+                this.write_int(1, dest)?;
             }
             "GetModuleHandleA" if this.frame_in_std() => {
                 #[allow(non_snake_case)]
                 let [_lpModuleName] =
                     this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
                 // We need to return something non-null here to make `compat_fn!` work.
-                this.write_scalar(Scalar::from_machine_isize(1, this), dest)?;
+                this.write_int(1, dest)?;
             }
             "SetConsoleTextAttribute" if this.frame_in_std() => {
                 #[allow(non_snake_case)]
@@ -408,24 +429,39 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 // Pretend these does not exist / nothing happened, by returning zero.
                 this.write_null(dest)?;
             }
+            "GetConsoleMode" if this.frame_in_std() => {
+                let [console, mode] =
+                    this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
+                this.read_scalar(console)?.to_machine_isize(this)?;
+                this.deref_operand(mode)?;
+                // Indicate an error.
+                this.write_null(dest)?;
+            }
+            "GetFileType" if this.frame_in_std() => {
+                #[allow(non_snake_case)]
+                let [_hFile] =
+                    this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
+                // Return unknown file type.
+                this.write_null(dest)?;
+            }
             "AddVectoredExceptionHandler" if this.frame_in_std() => {
                 #[allow(non_snake_case)]
                 let [_First, _Handler] =
                     this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
                 // Any non zero value works for the stdlib. This is just used for stack overflows anyway.
-                this.write_scalar(Scalar::from_machine_usize(1, this), dest)?;
+                this.write_int(1, dest)?;
             }
             "SetThreadStackGuarantee" if this.frame_in_std() => {
                 #[allow(non_snake_case)]
                 let [_StackSizeInBytes] =
                     this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
                 // Any non zero value works for the stdlib. This is just used for stack overflows anyway.
-                this.write_scalar(Scalar::from_u32(1), dest)?;
+                this.write_int(1, dest)?;
             }
             "GetCurrentProcessId" if this.frame_in_std() => {
                 let [] = this.check_shim(abi, Abi::System { unwind: false }, link_name, args)?;
                 let result = this.GetCurrentProcessId()?;
-                this.write_scalar(Scalar::from_u32(result), dest)?;
+                this.write_int(result, dest)?;
             }
             // this is only callable from std because we know that std ignores the return value
             "SwitchToThread" if this.frame_in_std() => {
diff --git a/src/tools/miri/src/shims/windows/sync.rs b/src/tools/miri/src/shims/windows/sync.rs
index dc1052a824de..8f414d98dba5 100644
--- a/src/tools/miri/src/shims/windows/sync.rs
+++ b/src/tools/miri/src/shims/windows/sync.rs
@@ -1,41 +1,54 @@
+use std::time::Duration;
+
+use rustc_target::abi::Size;
+
+use crate::concurrency::init_once::InitOnceStatus;
+use crate::concurrency::sync::{CondvarLock, RwLockMode};
+use crate::concurrency::thread::MachineCallback;
 use crate::*;
 
-// Locks are pointer-sized pieces of data, initialized to 0.
-// We use the first 4 bytes to store the RwLockId.
+const SRWLOCK_ID_OFFSET: u64 = 0;
+const INIT_ONCE_ID_OFFSET: u64 = 0;
+const CONDVAR_ID_OFFSET: u64 = 0;
 
-fn srwlock_get_or_create_id<'mir, 'tcx: 'mir>(
-    ecx: &mut MiriInterpCx<'mir, 'tcx>,
-    lock_op: &OpTy<'tcx, Provenance>,
-) -> InterpResult<'tcx, RwLockId> {
-    let value_place = ecx.deref_operand_and_offset(lock_op, 0, ecx.machine.layouts.u32)?;
+impl<'mir, 'tcx> EvalContextExtPriv<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+trait EvalContextExtPriv<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
+    /// Try to reacquire the lock associated with the condition variable after we
+    /// were signaled.
+    fn reacquire_cond_lock(
+        &mut self,
+        thread: ThreadId,
+        lock: RwLockId,
+        mode: RwLockMode,
+    ) -> InterpResult<'tcx> {
+        let this = self.eval_context_mut();
+        this.unblock_thread(thread);
 
-    ecx.rwlock_get_or_create(|ecx, next_id| {
-        let (old, success) = ecx
-            .atomic_compare_exchange_scalar(
-                &value_place,
-                &ImmTy::from_uint(0u32, ecx.machine.layouts.u32),
-                next_id.to_u32_scalar(),
-                AtomicRwOrd::Relaxed,
-                AtomicReadOrd::Relaxed,
-                false,
-            )?
-            .to_scalar_pair();
+        match mode {
+            RwLockMode::Read =>
+                if this.rwlock_is_write_locked(lock) {
+                    this.rwlock_enqueue_and_block_reader(lock, thread);
+                } else {
+                    this.rwlock_reader_lock(lock, thread);
+                },
+            RwLockMode::Write =>
+                if this.rwlock_is_locked(lock) {
+                    this.rwlock_enqueue_and_block_writer(lock, thread);
+                } else {
+                    this.rwlock_writer_lock(lock, thread);
+                },
+        }
 
-        Ok(if success.to_bool().expect("compare_exchange's second return value is a bool") {
-            // Caller of the closure needs to allocate next_id
-            None
-        } else {
-            Some(RwLockId::from_u32(old.to_u32().expect("layout is u32")))
-        })
-    })
+        Ok(())
+    }
 }
 
 impl<'mir, 'tcx> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
+#[allow(non_snake_case)]
 pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
-    #[allow(non_snake_case)]
     fn AcquireSRWLockExclusive(&mut self, lock_op: &OpTy<'tcx, Provenance>) -> InterpResult<'tcx> {
         let this = self.eval_context_mut();
-        let id = srwlock_get_or_create_id(this, lock_op)?;
+        let id = this.rwlock_get_or_create_id(lock_op, SRWLOCK_ID_OFFSET)?;
         let active_thread = this.get_active_thread();
 
         if this.rwlock_is_locked(id) {
@@ -54,28 +67,26 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         Ok(())
     }
 
-    #[allow(non_snake_case)]
     fn TryAcquireSRWLockExclusive(
         &mut self,
         lock_op: &OpTy<'tcx, Provenance>,
-    ) -> InterpResult<'tcx, u8> {
+    ) -> InterpResult<'tcx, Scalar<Provenance>> {
         let this = self.eval_context_mut();
-        let id = srwlock_get_or_create_id(this, lock_op)?;
+        let id = this.rwlock_get_or_create_id(lock_op, SRWLOCK_ID_OFFSET)?;
         let active_thread = this.get_active_thread();
 
         if this.rwlock_is_locked(id) {
             // Lock is already held.
-            Ok(0)
+            Ok(Scalar::from_u8(0))
         } else {
             this.rwlock_writer_lock(id, active_thread);
-            Ok(1)
+            Ok(Scalar::from_u8(1))
         }
     }
 
-    #[allow(non_snake_case)]
     fn ReleaseSRWLockExclusive(&mut self, lock_op: &OpTy<'tcx, Provenance>) -> InterpResult<'tcx> {
         let this = self.eval_context_mut();
-        let id = srwlock_get_or_create_id(this, lock_op)?;
+        let id = this.rwlock_get_or_create_id(lock_op, SRWLOCK_ID_OFFSET)?;
         let active_thread = this.get_active_thread();
 
         if !this.rwlock_writer_unlock(id, active_thread) {
@@ -88,10 +99,9 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         Ok(())
     }
 
-    #[allow(non_snake_case)]
     fn AcquireSRWLockShared(&mut self, lock_op: &OpTy<'tcx, Provenance>) -> InterpResult<'tcx> {
         let this = self.eval_context_mut();
-        let id = srwlock_get_or_create_id(this, lock_op)?;
+        let id = this.rwlock_get_or_create_id(lock_op, SRWLOCK_ID_OFFSET)?;
         let active_thread = this.get_active_thread();
 
         if this.rwlock_is_write_locked(id) {
@@ -103,27 +113,25 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         Ok(())
     }
 
-    #[allow(non_snake_case)]
     fn TryAcquireSRWLockShared(
         &mut self,
         lock_op: &OpTy<'tcx, Provenance>,
-    ) -> InterpResult<'tcx, u8> {
+    ) -> InterpResult<'tcx, Scalar<Provenance>> {
         let this = self.eval_context_mut();
-        let id = srwlock_get_or_create_id(this, lock_op)?;
+        let id = this.rwlock_get_or_create_id(lock_op, SRWLOCK_ID_OFFSET)?;
         let active_thread = this.get_active_thread();
 
         if this.rwlock_is_write_locked(id) {
-            Ok(0)
+            Ok(Scalar::from_u8(0))
         } else {
             this.rwlock_reader_lock(id, active_thread);
-            Ok(1)
+            Ok(Scalar::from_u8(1))
         }
     }
 
-    #[allow(non_snake_case)]
     fn ReleaseSRWLockShared(&mut self, lock_op: &OpTy<'tcx, Provenance>) -> InterpResult<'tcx> {
         let this = self.eval_context_mut();
-        let id = srwlock_get_or_create_id(this, lock_op)?;
+        let id = this.rwlock_get_or_create_id(lock_op, SRWLOCK_ID_OFFSET)?;
         let active_thread = this.get_active_thread();
 
         if !this.rwlock_reader_unlock(id, active_thread) {
@@ -135,4 +143,349 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
 
         Ok(())
     }
+
+    fn InitOnceBeginInitialize(
+        &mut self,
+        init_once_op: &OpTy<'tcx, Provenance>,
+        flags_op: &OpTy<'tcx, Provenance>,
+        pending_op: &OpTy<'tcx, Provenance>,
+        context_op: &OpTy<'tcx, Provenance>,
+    ) -> InterpResult<'tcx, Scalar<Provenance>> {
+        let this = self.eval_context_mut();
+        let active_thread = this.get_active_thread();
+
+        let id = this.init_once_get_or_create_id(init_once_op, INIT_ONCE_ID_OFFSET)?;
+        let flags = this.read_scalar(flags_op)?.to_u32()?;
+        let pending_place = this.deref_operand(pending_op)?.into();
+        let context = this.read_pointer(context_op)?;
+
+        if flags != 0 {
+            throw_unsup_format!("unsupported `dwFlags` {flags} in `InitOnceBeginInitialize`");
+        }
+
+        if !this.ptr_is_null(context)? {
+            throw_unsup_format!("non-null `lpContext` in `InitOnceBeginInitialize`");
+        }
+
+        match this.init_once_status(id) {
+            InitOnceStatus::Uninitialized => {
+                this.init_once_begin(id);
+                this.write_scalar(this.eval_windows("c", "TRUE")?, &pending_place)?;
+            }
+            InitOnceStatus::Begun => {
+                // Someone else is already on it.
+                // Block this thread until they are done.
+                // When we are woken up, set the `pending` flag accordingly.
+                struct Callback<'tcx> {
+                    init_once_id: InitOnceId,
+                    pending_place: PlaceTy<'tcx, Provenance>,
+                }
+
+                impl<'tcx> VisitTags for Callback<'tcx> {
+                    fn visit_tags(&self, visit: &mut dyn FnMut(SbTag)) {
+                        let Callback { init_once_id: _, pending_place } = self;
+                        pending_place.visit_tags(visit);
+                    }
+                }
+
+                impl<'mir, 'tcx> MachineCallback<'mir, 'tcx> for Callback<'tcx> {
+                    fn call(&self, this: &mut MiriInterpCx<'mir, 'tcx>) -> InterpResult<'tcx> {
+                        let pending = match this.init_once_status(self.init_once_id) {
+                            InitOnceStatus::Uninitialized =>
+                                unreachable!(
+                                    "status should have either been set to begun or complete"
+                                ),
+                            InitOnceStatus::Begun => this.eval_windows("c", "TRUE")?,
+                            InitOnceStatus::Complete => this.eval_windows("c", "FALSE")?,
+                        };
+
+                        this.write_scalar(pending, &self.pending_place)?;
+
+                        Ok(())
+                    }
+                }
+
+                this.init_once_enqueue_and_block(
+                    id,
+                    active_thread,
+                    Box::new(Callback { init_once_id: id, pending_place }),
+                )
+            }
+            InitOnceStatus::Complete => {
+                this.init_once_observe_completed(id);
+                this.write_scalar(this.eval_windows("c", "FALSE")?, &pending_place)?;
+            }
+        }
+
+        // This always succeeds (even if the thread is blocked, we will succeed if we ever unblock).
+        this.eval_windows("c", "TRUE")
+    }
+
+    fn InitOnceComplete(
+        &mut self,
+        init_once_op: &OpTy<'tcx, Provenance>,
+        flags_op: &OpTy<'tcx, Provenance>,
+        context_op: &OpTy<'tcx, Provenance>,
+    ) -> InterpResult<'tcx, Scalar<Provenance>> {
+        let this = self.eval_context_mut();
+
+        let id = this.init_once_get_or_create_id(init_once_op, INIT_ONCE_ID_OFFSET)?;
+        let flags = this.read_scalar(flags_op)?.to_u32()?;
+        let context = this.read_pointer(context_op)?;
+
+        let success = if flags == 0 {
+            true
+        } else if flags == this.eval_windows("c", "INIT_ONCE_INIT_FAILED")?.to_u32()? {
+            false
+        } else {
+            throw_unsup_format!("unsupported `dwFlags` {flags} in `InitOnceBeginInitialize`");
+        };
+
+        if !this.ptr_is_null(context)? {
+            throw_unsup_format!("non-null `lpContext` in `InitOnceBeginInitialize`");
+        }
+
+        if this.init_once_status(id) != InitOnceStatus::Begun {
+            // The docs do not say anything about this case, but it seems better to not allow it.
+            throw_ub_format!(
+                "calling InitOnceComplete on a one time initialization that has not begun or is already completed"
+            );
+        }
+
+        if success {
+            this.init_once_complete(id)?;
+        } else {
+            this.init_once_fail(id)?;
+        }
+
+        this.eval_windows("c", "TRUE")
+    }
+
+    fn WaitOnAddress(
+        &mut self,
+        ptr_op: &OpTy<'tcx, Provenance>,
+        compare_op: &OpTy<'tcx, Provenance>,
+        size_op: &OpTy<'tcx, Provenance>,
+        timeout_op: &OpTy<'tcx, Provenance>,
+        dest: &PlaceTy<'tcx, Provenance>,
+    ) -> InterpResult<'tcx> {
+        let this = self.eval_context_mut();
+
+        let ptr = this.read_pointer(ptr_op)?;
+        let compare = this.read_pointer(compare_op)?;
+        let size = this.read_scalar(size_op)?.to_machine_usize(this)?;
+        let timeout_ms = this.read_scalar(timeout_op)?.to_u32()?;
+
+        let thread = this.get_active_thread();
+        let addr = ptr.addr().bytes();
+
+        if size > 8 || !size.is_power_of_two() {
+            let invalid_param = this.eval_windows("c", "ERROR_INVALID_PARAMETER")?;
+            this.set_last_error(invalid_param)?;
+            this.write_scalar(Scalar::from_i32(0), dest)?;
+            return Ok(());
+        };
+        let size = Size::from_bytes(size);
+
+        let timeout_time = if timeout_ms == this.eval_windows("c", "INFINITE")?.to_u32()? {
+            None
+        } else {
+            let duration = Duration::from_millis(timeout_ms.into());
+            Some(Time::Monotonic(this.machine.clock.now().checked_add(duration).unwrap()))
+        };
+
+        // See the Linux futex implementation for why this fence exists.
+        this.atomic_fence(AtomicFenceOrd::SeqCst)?;
+
+        let layout = this.machine.layouts.uint(size).unwrap();
+        let futex_val = this
+            .read_scalar_atomic(&MPlaceTy::from_aligned_ptr(ptr, layout), AtomicReadOrd::Relaxed)?;
+        let compare_val = this.read_scalar(&MPlaceTy::from_aligned_ptr(compare, layout).into())?;
+
+        if futex_val == compare_val {
+            // If the values are the same, we have to block.
+            this.block_thread(thread);
+            this.futex_wait(addr, thread, u32::MAX);
+
+            if let Some(timeout_time) = timeout_time {
+                struct Callback<'tcx> {
+                    thread: ThreadId,
+                    addr: u64,
+                    dest: PlaceTy<'tcx, Provenance>,
+                }
+
+                impl<'tcx> VisitTags for Callback<'tcx> {
+                    fn visit_tags(&self, visit: &mut dyn FnMut(SbTag)) {
+                        let Callback { thread: _, addr: _, dest } = self;
+                        dest.visit_tags(visit);
+                    }
+                }
+
+                impl<'mir, 'tcx: 'mir> MachineCallback<'mir, 'tcx> for Callback<'tcx> {
+                    fn call(&self, this: &mut MiriInterpCx<'mir, 'tcx>) -> InterpResult<'tcx> {
+                        this.unblock_thread(self.thread);
+                        this.futex_remove_waiter(self.addr, self.thread);
+                        let error_timeout = this.eval_windows("c", "ERROR_TIMEOUT")?;
+                        this.set_last_error(error_timeout)?;
+                        this.write_scalar(Scalar::from_i32(0), &self.dest)?;
+
+                        Ok(())
+                    }
+                }
+
+                this.register_timeout_callback(
+                    thread,
+                    timeout_time,
+                    Box::new(Callback { thread, addr, dest: dest.clone() }),
+                );
+            }
+        }
+
+        this.write_scalar(Scalar::from_i32(1), dest)?;
+
+        Ok(())
+    }
+
+    fn WakeByAddressSingle(&mut self, ptr_op: &OpTy<'tcx, Provenance>) -> InterpResult<'tcx> {
+        let this = self.eval_context_mut();
+
+        let ptr = this.read_pointer(ptr_op)?;
+
+        // See the Linux futex implementation for why this fence exists.
+        this.atomic_fence(AtomicFenceOrd::SeqCst)?;
+
+        if let Some(thread) = this.futex_wake(ptr.addr().bytes(), u32::MAX) {
+            this.unblock_thread(thread);
+            this.unregister_timeout_callback_if_exists(thread);
+        }
+
+        Ok(())
+    }
+
+    fn SleepConditionVariableSRW(
+        &mut self,
+        condvar_op: &OpTy<'tcx, Provenance>,
+        lock_op: &OpTy<'tcx, Provenance>,
+        timeout_op: &OpTy<'tcx, Provenance>,
+        flags_op: &OpTy<'tcx, Provenance>,
+        dest: &PlaceTy<'tcx, Provenance>,
+    ) -> InterpResult<'tcx, Scalar<Provenance>> {
+        let this = self.eval_context_mut();
+
+        let condvar_id = this.condvar_get_or_create_id(condvar_op, CONDVAR_ID_OFFSET)?;
+        let lock_id = this.rwlock_get_or_create_id(lock_op, SRWLOCK_ID_OFFSET)?;
+        let timeout_ms = this.read_scalar(timeout_op)?.to_u32()?;
+        let flags = this.read_scalar(flags_op)?.to_u32()?;
+
+        let timeout_time = if timeout_ms == this.eval_windows("c", "INFINITE")?.to_u32()? {
+            None
+        } else {
+            let duration = Duration::from_millis(timeout_ms.into());
+            Some(this.machine.clock.now().checked_add(duration).unwrap())
+        };
+
+        let shared_mode = 0x1; // CONDITION_VARIABLE_LOCKMODE_SHARED is not in std
+        let mode = if flags == 0 {
+            RwLockMode::Write
+        } else if flags == shared_mode {
+            RwLockMode::Read
+        } else {
+            throw_unsup_format!("unsupported `Flags` {flags} in `SleepConditionVariableSRW`");
+        };
+
+        let active_thread = this.get_active_thread();
+
+        let was_locked = match mode {
+            RwLockMode::Read => this.rwlock_reader_unlock(lock_id, active_thread),
+            RwLockMode::Write => this.rwlock_writer_unlock(lock_id, active_thread),
+        };
+
+        if !was_locked {
+            throw_ub_format!(
+                "calling SleepConditionVariableSRW with an SRWLock that is not locked by the current thread"
+            );
+        }
+
+        this.block_thread(active_thread);
+        this.condvar_wait(condvar_id, active_thread, CondvarLock::RwLock { id: lock_id, mode });
+
+        if let Some(timeout_time) = timeout_time {
+            struct Callback<'tcx> {
+                thread: ThreadId,
+                condvar_id: CondvarId,
+                lock_id: RwLockId,
+                mode: RwLockMode,
+                dest: PlaceTy<'tcx, Provenance>,
+            }
+
+            impl<'tcx> VisitTags for Callback<'tcx> {
+                fn visit_tags(&self, visit: &mut dyn FnMut(SbTag)) {
+                    let Callback { thread: _, condvar_id: _, lock_id: _, mode: _, dest } = self;
+                    dest.visit_tags(visit);
+                }
+            }
+
+            impl<'mir, 'tcx: 'mir> MachineCallback<'mir, 'tcx> for Callback<'tcx> {
+                fn call(&self, this: &mut MiriInterpCx<'mir, 'tcx>) -> InterpResult<'tcx> {
+                    this.reacquire_cond_lock(self.thread, self.lock_id, self.mode)?;
+
+                    this.condvar_remove_waiter(self.condvar_id, self.thread);
+
+                    let error_timeout = this.eval_windows("c", "ERROR_TIMEOUT")?;
+                    this.set_last_error(error_timeout)?;
+                    this.write_scalar(this.eval_windows("c", "FALSE")?, &self.dest)?;
+                    Ok(())
+                }
+            }
+
+            this.register_timeout_callback(
+                active_thread,
+                Time::Monotonic(timeout_time),
+                Box::new(Callback {
+                    thread: active_thread,
+                    condvar_id,
+                    lock_id,
+                    mode,
+                    dest: dest.clone(),
+                }),
+            );
+        }
+
+        this.eval_windows("c", "TRUE")
+    }
+
+    fn WakeConditionVariable(&mut self, condvar_op: &OpTy<'tcx, Provenance>) -> InterpResult<'tcx> {
+        let this = self.eval_context_mut();
+        let condvar_id = this.condvar_get_or_create_id(condvar_op, CONDVAR_ID_OFFSET)?;
+
+        if let Some((thread, lock)) = this.condvar_signal(condvar_id) {
+            if let CondvarLock::RwLock { id, mode } = lock {
+                this.reacquire_cond_lock(thread, id, mode)?;
+                this.unregister_timeout_callback_if_exists(thread);
+            } else {
+                panic!("mutexes should not exist on windows");
+            }
+        }
+
+        Ok(())
+    }
+
+    fn WakeAllConditionVariable(
+        &mut self,
+        condvar_op: &OpTy<'tcx, Provenance>,
+    ) -> InterpResult<'tcx> {
+        let this = self.eval_context_mut();
+        let condvar_id = this.condvar_get_or_create_id(condvar_op, CONDVAR_ID_OFFSET)?;
+
+        while let Some((thread, lock)) = this.condvar_signal(condvar_id) {
+            if let CondvarLock::RwLock { id, mode } = lock {
+                this.reacquire_cond_lock(thread, id, mode)?;
+                this.unregister_timeout_callback_if_exists(thread);
+            } else {
+                panic!("mutexes should not exist on windows");
+            }
+        }
+
+        Ok(())
+    }
 }
diff --git a/src/tools/miri/src/stacked_borrows/diagnostics.rs b/src/tools/miri/src/stacked_borrows/diagnostics.rs
index 2cc7a88704ea..d3843b030347 100644
--- a/src/tools/miri/src/stacked_borrows/diagnostics.rs
+++ b/src/tools/miri/src/stacked_borrows/diagnostics.rs
@@ -86,12 +86,12 @@ impl Invalidation {
 impl fmt::Display for InvalidationCause {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match self {
-            InvalidationCause::Access(kind) => write!(f, "{}", kind),
+            InvalidationCause::Access(kind) => write!(f, "{kind}"),
             InvalidationCause::Retag(perm, kind) =>
                 if *kind == RetagCause::FnEntry {
-                    write!(f, "{:?} FnEntry retag", perm)
+                    write!(f, "{perm:?} FnEntry retag")
                 } else {
-                    write!(f, "{:?} retag", perm)
+                    write!(f, "{perm:?} retag")
                 },
         }
     }
@@ -339,7 +339,7 @@ impl<'span, 'history, 'ecx, 'mir, 'tcx> DiagnosticCx<'span, 'history, 'ecx, 'mir
                 // this allocation.
                 if self.history.base.0.tag() == tag {
                     Some((
-                        format!("{:?} was created here, as the base tag for {:?}", tag, self.history.id),
+                        format!("{tag:?} was created here, as the base tag for {:?}", self.history.id),
                         self.history.base.1.data()
                     ))
                 } else {
@@ -381,7 +381,7 @@ impl<'span, 'history, 'ecx, 'mir, 'tcx> DiagnosticCx<'span, 'history, 'ecx, 'mir
             self.offset.bytes(),
         );
         err_sb_ub(
-            format!("{}{}", action, error_cause(stack, op.orig_tag)),
+            format!("{action}{}", error_cause(stack, op.orig_tag)),
             Some(operation_summary(&op.cause.summary(), self.history.id, op.range)),
             op.orig_tag.and_then(|orig_tag| self.get_logs_relevant_to(orig_tag, None)),
         )
@@ -401,7 +401,7 @@ impl<'span, 'history, 'ecx, 'mir, 'tcx> DiagnosticCx<'span, 'history, 'ecx, 'mir
             offset = self.offset.bytes(),
         );
         err_sb_ub(
-            format!("{}{}", action, error_cause(stack, op.tag)),
+            format!("{action}{}", error_cause(stack, op.tag)),
             Some(operation_summary("an access", self.history.id, op.range)),
             op.tag.and_then(|tag| self.get_logs_relevant_to(tag, None)),
         )
diff --git a/src/tools/miri/src/stacked_borrows/mod.rs b/src/tools/miri/src/stacked_borrows/mod.rs
index 2888f8e81fb5..9ce02a02ec40 100644
--- a/src/tools/miri/src/stacked_borrows/mod.rs
+++ b/src/tools/miri/src/stacked_borrows/mod.rs
@@ -16,7 +16,7 @@ use rustc_middle::ty::{
     layout::{HasParamEnv, LayoutOf},
     Ty,
 };
-use rustc_span::DUMMY_SP;
+use rustc_target::abi::Abi;
 use rustc_target::abi::Size;
 use smallvec::SmallVec;
 
@@ -45,6 +45,7 @@ impl SbTag {
     }
 
     // The default to be used when SB is disabled
+    #[allow(clippy::should_implement_trait)]
     pub fn default() -> Self {
         Self::new(1).unwrap()
     }
@@ -113,7 +114,18 @@ pub struct GlobalStateInner {
     /// The call ids to trace
     tracked_call_ids: FxHashSet<CallId>,
     /// Whether to recurse into datatypes when searching for pointers to retag.
-    retag_fields: bool,
+    retag_fields: RetagFields,
+}
+
+#[derive(Copy, Clone, Debug)]
+pub enum RetagFields {
+    /// Don't retag any fields.
+    No,
+    /// Retag all fields.
+    Yes,
+    /// Only retag fields of types with Scalar and ScalarPair layout,
+    /// to match the LLVM `noalias` we generate.
+    OnlyScalar,
 }
 
 impl VisitTags for GlobalStateInner {
@@ -172,7 +184,7 @@ impl GlobalStateInner {
     pub fn new(
         tracked_pointer_tags: FxHashSet<SbTag>,
         tracked_call_ids: FxHashSet<CallId>,
-        retag_fields: bool,
+        retag_fields: RetagFields,
     ) -> Self {
         GlobalStateInner {
             next_ptr_tag: SbTag(NonZeroU64::new(1).unwrap()),
@@ -240,7 +252,7 @@ pub fn err_sb_ub<'tcx>(
 /// We need to make at least the following things true:
 ///
 /// U1: After creating a `Uniq`, it is at the top.
-/// U2: If the top is `Uniq`, accesses must be through that `Uniq` or remove it it.
+/// U2: If the top is `Uniq`, accesses must be through that `Uniq` or remove it.
 /// U3: If an access happens with a `Uniq`, it requires the `Uniq` to be in the stack.
 ///
 /// F1: After creating a `&`, the parts outside `UnsafeCell` have our `SharedReadOnly` on top.
@@ -701,12 +713,12 @@ trait EvalContextPrivExt<'mir: 'ecx, 'tcx: 'mir, 'ecx>: crate::MiriInterpCxExt<'
                 let mut kind_str = format!("{kind}");
                 match kind {
                     RefKind::Unique { two_phase: false }
-                        if !ty.is_unpin(this.tcx.at(DUMMY_SP), this.param_env()) =>
+                        if !ty.is_unpin(*this.tcx, this.param_env()) =>
                     {
                         write!(kind_str, " (!Unpin pointee type {ty})").unwrap()
                     },
                     RefKind::Shared
-                        if !ty.is_freeze(this.tcx.at(DUMMY_SP), this.param_env()) =>
+                        if !ty.is_freeze(*this.tcx, this.param_env()) =>
                     {
                         write!(kind_str, " (!Freeze pointee type {ty})").unwrap()
                     },
@@ -821,7 +833,7 @@ trait EvalContextPrivExt<'mir: 'ecx, 'tcx: 'mir, 'ecx>: crate::MiriInterpCxExt<'
         // There could be existing unique pointers reborrowed from them that should remain valid!
         let perm = match kind {
             RefKind::Unique { two_phase: false }
-                if place.layout.ty.is_unpin(this.tcx.at(DUMMY_SP), this.param_env()) =>
+                if place.layout.ty.is_unpin(*this.tcx, this.param_env()) =>
             {
                 // Only if the type is unpin do we actually enforce uniqueness
                 Permission::Unique
@@ -998,7 +1010,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             ecx: &'ecx mut MiriInterpCx<'mir, 'tcx>,
             kind: RetagKind,
             retag_cause: RetagCause,
-            retag_fields: bool,
+            retag_fields: RetagFields,
         }
         impl<'ecx, 'mir, 'tcx> RetagVisitor<'ecx, 'mir, 'tcx> {
             #[inline(always)] // yes this helps in our benchmarks
@@ -1041,10 +1053,22 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 // pointers we need to retag, so we can stop recursion early.
                 // This optimization is crucial for ZSTs, because they can contain way more fields
                 // than we can ever visit.
-                if !place.layout.is_unsized() && place.layout.size < self.ecx.pointer_size() {
+                if place.layout.is_sized() && place.layout.size < self.ecx.pointer_size() {
                     return Ok(());
                 }
 
+                let recurse_for_fields = || {
+                    match self.retag_fields {
+                        RetagFields::No => false,
+                        RetagFields::Yes => true,
+                        RetagFields::OnlyScalar => {
+                            // Matching `ArgAbi::new` at the time of writing, only fields of
+                            // `Scalar` and `ScalarPair` ABI are considered.
+                            matches!(place.layout.abi, Abi::Scalar(..) | Abi::ScalarPair(..))
+                        }
+                    }
+                };
+
                 if let Some((ref_kind, protector)) = qualify(place.layout.ty, self.kind) {
                     self.retag_place(place, ref_kind, self.retag_cause, protector)?;
                 } else if matches!(place.layout.ty.kind(), ty::RawPtr(..)) {
@@ -1053,7 +1077,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                     // Do *not* recurse into them.
                     // (No need to worry about wide references, those always "qualify". And Boxes
                     // are handles specially by the visitor anyway.)
-                } else if self.retag_fields
+                } else if recurse_for_fields()
                     || place.layout.ty.ty_adt_def().is_some_and(|adt| adt.is_box())
                 {
                     // Recurse deeper. Need to always recurse for `Box` to even hit `visit_box`.
@@ -1122,4 +1146,22 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
         }
         Ok(())
     }
+
+    fn print_stacks(&mut self, alloc_id: AllocId) -> InterpResult<'tcx> {
+        let this = self.eval_context_mut();
+        let alloc_extra = this.get_alloc_extra(alloc_id)?;
+        let stacks = alloc_extra.stacked_borrows.as_ref().unwrap().borrow();
+        for (range, stack) in stacks.stacks.iter_all() {
+            print!("{range:?}: [");
+            if let Some(bottom) = stack.unknown_bottom() {
+                print!(" unknown-bottom(..{bottom:?})");
+            }
+            for i in 0..stack.len() {
+                let item = stack.get(i).unwrap();
+                print!(" {:?}{:?}", item.perm(), item.tag());
+            }
+            println!(" ]");
+        }
+        Ok(())
+    }
 }
diff --git a/src/tools/miri/src/stacked_borrows/stack.rs b/src/tools/miri/src/stacked_borrows/stack.rs
index 07c211512f87..aa549e34c5f6 100644
--- a/src/tools/miri/src/stacked_borrows/stack.rs
+++ b/src/tools/miri/src/stacked_borrows/stack.rs
@@ -43,10 +43,14 @@ impl Stack {
     pub fn retain(&mut self, tags: &FxHashSet<SbTag>) {
         let mut first_removed = None;
 
-        // For stacks with a known bottom, we never consider removing the bottom-most tag, because
-        // that is the base tag which exists whether or not there are any pointers to the
-        // allocation.
-        let mut read_idx = if self.unknown_bottom.is_some() { 0 } else { 1 };
+        // We never consider removing the bottom-most tag. For stacks without an unknown
+        // bottom this preserves the base tag.
+        // Note that the algorithm below is based on considering the tag at read_idx - 1,
+        // so precisely considering the tag at index 0 for removal when we have an unknown
+        // bottom would complicate the implementation. The simplification of not considering
+        // it does not have a significant impact on the degree to which the GC mititages
+        // memory growth.
+        let mut read_idx = 1;
         let mut write_idx = read_idx;
         while read_idx < self.borrows.len() {
             let left = self.borrows[read_idx - 1];
diff --git a/src/tools/miri/test-cargo-miri/run-test.py b/src/tools/miri/test-cargo-miri/run-test.py
index 4485d3252ccc..c611b9c44be9 100755
--- a/src/tools/miri/test-cargo-miri/run-test.py
+++ b/src/tools/miri/test-cargo-miri/run-test.py
@@ -33,10 +33,13 @@ def normalize_stderr(str):
     return str
 
 def check_output(actual, path, name):
+    if 'MIRI_BLESS' in os.environ:
+        open(path, mode='w').write(actual)
+        return True
     expected = open(path).read()
     if expected == actual:
         return True
-    print(f"{path} did not match reference!")
+    print(f"{name} output did not match reference in {path}!")
     print(f"--- BEGIN diff {name} ---")
     for text in difflib.unified_diff(expected.split("\n"), actual.split("\n")):
         print(text)
diff --git a/src/tools/miri/tests/compiletest.rs b/src/tools/miri/tests/compiletest.rs
index 4789d22eb4f9..65fd7c2eccb5 100644
--- a/src/tools/miri/tests/compiletest.rs
+++ b/src/tools/miri/tests/compiletest.rs
@@ -8,6 +8,12 @@ fn miri_path() -> PathBuf {
     PathBuf::from(option_env!("MIRI").unwrap_or(env!("CARGO_BIN_EXE_miri")))
 }
 
+fn get_host() -> String {
+    rustc_version::VersionMeta::for_command(std::process::Command::new(miri_path()))
+        .expect("failed to parse rustc version info")
+        .host
+}
+
 // Build the shared object file for testing external C function calls.
 fn build_so_for_c_ffi_tests() -> PathBuf {
     let cc = option_env!("CC").unwrap_or("cc");
@@ -37,14 +43,9 @@ fn build_so_for_c_ffi_tests() -> PathBuf {
     so_file_path
 }
 
-fn run_tests(
-    mode: Mode,
-    path: &str,
-    target: Option<String>,
-    with_dependencies: bool,
-) -> Result<()> {
+fn run_tests(mode: Mode, path: &str, target: &str, with_dependencies: bool) -> Result<()> {
     let mut config = Config {
-        target,
+        target: Some(target.to_owned()),
         stderr_filters: STDERR.clone(),
         stdout_filters: STDOUT.clone(),
         root_dir: PathBuf::from(path),
@@ -138,6 +139,8 @@ regexes! {
     STDOUT:
     // Windows file paths
     r"\\"                           => "/",
+    // erase Stacked Borrows tags
+    "<[0-9]+>"                      => "<TAG>",
 }
 
 regexes! {
@@ -179,13 +182,8 @@ enum Dependencies {
 
 use Dependencies::*;
 
-fn ui(mode: Mode, path: &str, with_dependencies: Dependencies) -> Result<()> {
-    let target = get_target();
-
-    let msg = format!(
-        "## Running ui tests in {path} against miri for {}",
-        target.as_deref().unwrap_or("host")
-    );
+fn ui(mode: Mode, path: &str, target: &str, with_dependencies: Dependencies) -> Result<()> {
+    let msg = format!("## Running ui tests in {path} against miri for {target}");
     eprintln!("{}", msg.green().bold());
 
     let with_dependencies = match with_dependencies {
@@ -195,25 +193,31 @@ fn ui(mode: Mode, path: &str, with_dependencies: Dependencies) -> Result<()> {
     run_tests(mode, path, target, with_dependencies)
 }
 
-fn get_target() -> Option<String> {
-    env::var("MIRI_TEST_TARGET").ok()
+fn get_target() -> String {
+    env::var("MIRI_TEST_TARGET").ok().unwrap_or_else(get_host)
 }
 
 fn main() -> Result<()> {
     ui_test::color_eyre::install()?;
+    let target = get_target();
 
     // Add a test env var to do environment communication tests.
     env::set_var("MIRI_ENV_VAR_TEST", "0");
     // Let the tests know where to store temp files (they might run for a different target, which can make this hard to find).
     env::set_var("MIRI_TEMP", env::temp_dir());
 
-    ui(Mode::Pass, "tests/pass", WithoutDependencies)?;
-    ui(Mode::Pass, "tests/pass-dep", WithDependencies)?;
-    ui(Mode::Panic, "tests/panic", WithDependencies)?;
-    ui(Mode::Fail { require_patterns: true }, "tests/fail", WithDependencies)?;
+    ui(Mode::Pass, "tests/pass", &target, WithoutDependencies)?;
+    ui(Mode::Pass, "tests/pass-dep", &target, WithDependencies)?;
+    ui(Mode::Panic, "tests/panic", &target, WithDependencies)?;
+    ui(Mode::Fail { require_patterns: true }, "tests/fail", &target, WithDependencies)?;
     if cfg!(target_os = "linux") {
-        ui(Mode::Pass, "tests/extern-so/pass", WithoutDependencies)?;
-        ui(Mode::Fail { require_patterns: true }, "tests/extern-so/fail", WithoutDependencies)?;
+        ui(Mode::Pass, "tests/extern-so/pass", &target, WithoutDependencies)?;
+        ui(
+            Mode::Fail { require_patterns: true },
+            "tests/extern-so/fail",
+            &target,
+            WithoutDependencies,
+        )?;
     }
 
     Ok(())
diff --git a/src/tools/miri/tests/fail/data_race/stack_pop_race.rs b/src/tools/miri/tests/fail/data_race/stack_pop_race.rs
index 8f371a680f11..163f46eacc19 100644
--- a/src/tools/miri/tests/fail/data_race/stack_pop_race.rs
+++ b/src/tools/miri/tests/fail/data_race/stack_pop_race.rs
@@ -1,4 +1,3 @@
-//@ignore-target-windows: Concurrency on Windows is not supported yet.
 //@compile-flags: -Zmiri-preemption-rate=0
 use std::thread;
 
diff --git a/src/tools/miri/tests/fail/invalid_bool.rs b/src/tools/miri/tests/fail/invalid_bool.rs
index dde414f41774..fe9bb3bed7f0 100644
--- a/src/tools/miri/tests/fail/invalid_bool.rs
+++ b/src/tools/miri/tests/fail/invalid_bool.rs
@@ -2,7 +2,6 @@
 // Make sure we find these even with many checks disabled.
 //@compile-flags: -Zmiri-disable-alignment-check -Zmiri-disable-stacked-borrows -Zmiri-disable-validation
 
-
 fn main() {
     let b = unsafe { std::mem::transmute::<u8, bool>(2) };
     let _x = b == std::hint::black_box(true); //~ ERROR: interpreting an invalid 8-bit value as a bool
diff --git a/src/tools/miri/tests/fail/panic/no_std.rs b/src/tools/miri/tests/fail/panic/no_std.rs
new file mode 100644
index 000000000000..589f843cf827
--- /dev/null
+++ b/src/tools/miri/tests/fail/panic/no_std.rs
@@ -0,0 +1,41 @@
+#![feature(lang_items, start, core_intrinsics)]
+#![no_std]
+// windows tls dtors go through libstd right now, thus this test
+// cannot pass. When windows tls dtors go through the special magic
+// windows linker section, we can run this test on windows again.
+//@ignore-target-windows: no-std not supported on Windows
+
+// Plumbing to let us use `writeln!` to host stderr:
+
+extern "Rust" {
+    fn miri_write_to_stderr(bytes: &[u8]);
+}
+
+struct HostErr;
+
+use core::fmt::Write;
+
+impl Write for HostErr {
+    fn write_str(&mut self, s: &str) -> core::fmt::Result {
+        unsafe {
+            miri_write_to_stderr(s.as_bytes());
+        }
+        Ok(())
+    }
+}
+
+// Aaaand the test:
+
+#[start]
+fn start(_: isize, _: *const *const u8) -> isize {
+    panic!("blarg I am dead")
+}
+
+#[panic_handler]
+fn panic_handler(panic_info: &core::panic::PanicInfo) -> ! {
+    writeln!(HostErr, "{panic_info}").ok();
+    core::intrinsics::abort(); //~ ERROR: the program aborted execution
+}
+
+#[lang = "eh_personality"]
+fn eh_personality() {}
diff --git a/src/tools/miri/tests/fail/panic/no_std.stderr b/src/tools/miri/tests/fail/panic/no_std.stderr
new file mode 100644
index 000000000000..568b286e1d3b
--- /dev/null
+++ b/src/tools/miri/tests/fail/panic/no_std.stderr
@@ -0,0 +1,19 @@
+panicked at 'blarg I am dead', $DIR/no_std.rs:LL:CC
+error: abnormal termination: the program aborted execution
+  --> $DIR/no_std.rs:LL:CC
+   |
+LL |     core::intrinsics::abort();
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^ the program aborted execution
+   |
+   = note: inside `panic_handler` at $DIR/no_std.rs:LL:CC
+note: inside `start` at RUSTLIB/core/src/panic.rs:LL:CC
+  --> $DIR/no_std.rs:LL:CC
+   |
+LL |     panic!("blarg I am dead")
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
+   = note: this error originates in the macro `$crate::panic::panic_2015` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace
+
+error: aborting due to previous error
+
diff --git a/src/tools/miri/tests/fail/stacked_borrows/newtype_pair_retagging.rs b/src/tools/miri/tests/fail/stacked_borrows/newtype_pair_retagging.rs
new file mode 100644
index 000000000000..cc774500a3c6
--- /dev/null
+++ b/src/tools/miri/tests/fail/stacked_borrows/newtype_pair_retagging.rs
@@ -0,0 +1,18 @@
+//@error-pattern: which is protected
+struct Newtype<'a>(&'a mut i32, i32);
+
+fn dealloc_while_running(_n: Newtype<'_>, dealloc: impl FnOnce()) {
+    dealloc();
+}
+
+// Make sure that we protect references inside structs that are passed as ScalarPair.
+fn main() {
+    let ptr = Box::into_raw(Box::new(0i32));
+    #[rustfmt::skip] // I like my newlines
+    unsafe {
+        dealloc_while_running(
+            Newtype(&mut *ptr, 0),
+            || drop(Box::from_raw(ptr)),
+        )
+    };
+}
diff --git a/src/tools/miri/tests/fail/stacked_borrows/newtype_pair_retagging.stderr b/src/tools/miri/tests/fail/stacked_borrows/newtype_pair_retagging.stderr
new file mode 100644
index 000000000000..60a8b2a6260b
--- /dev/null
+++ b/src/tools/miri/tests/fail/stacked_borrows/newtype_pair_retagging.stderr
@@ -0,0 +1,44 @@
+error: Undefined Behavior: not granting access to tag <TAG> because that would remove [Unique for <TAG>] which is protected because it is an argument of call ID
+  --> RUSTLIB/alloc/src/boxed.rs:LL:CC
+   |
+LL |         Box(unsafe { Unique::new_unchecked(raw) }, alloc)
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not granting access to tag <TAG> because that would remove [Unique for <TAG>] which is protected because it is an argument of call ID
+   |
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
+   = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
+help: <TAG> was created by a SharedReadWrite retag at offsets [0x0..0x4]
+  --> $DIR/newtype_pair_retagging.rs:LL:CC
+   |
+LL |     let ptr = Box::into_raw(Box::new(0i32));
+   |               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+help: <TAG> is this argument
+  --> $DIR/newtype_pair_retagging.rs:LL:CC
+   |
+LL | fn dealloc_while_running(_n: Newtype<'_>, dealloc: impl FnOnce()) {
+   |                          ^^
+   = note: BACKTRACE:
+   = note: inside `std::boxed::Box::<i32>::from_raw_in` at RUSTLIB/alloc/src/boxed.rs:LL:CC
+   = note: inside `std::boxed::Box::<i32>::from_raw` at RUSTLIB/alloc/src/boxed.rs:LL:CC
+note: inside closure at $DIR/newtype_pair_retagging.rs:LL:CC
+  --> $DIR/newtype_pair_retagging.rs:LL:CC
+   |
+LL |             || drop(Box::from_raw(ptr)),
+   |                     ^^^^^^^^^^^^^^^^^^
+note: inside `dealloc_while_running::<[closure@$DIR/newtype_pair_retagging.rs:LL:CC]>` at $DIR/newtype_pair_retagging.rs:LL:CC
+  --> $DIR/newtype_pair_retagging.rs:LL:CC
+   |
+LL |     dealloc();
+   |     ^^^^^^^^^
+note: inside `main` at $DIR/newtype_pair_retagging.rs:LL:CC
+  --> $DIR/newtype_pair_retagging.rs:LL:CC
+   |
+LL | /         dealloc_while_running(
+LL | |             Newtype(&mut *ptr, 0),
+LL | |             || drop(Box::from_raw(ptr)),
+LL | |         )
+   | |_________^
+
+note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace
+
+error: aborting due to previous error
+
diff --git a/src/tools/miri/tests/fail/stacked_borrows/newtype_retagging.rs b/src/tools/miri/tests/fail/stacked_borrows/newtype_retagging.rs
index 6e7413cff5d4..1aa6e240e30f 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/newtype_retagging.rs
+++ b/src/tools/miri/tests/fail/stacked_borrows/newtype_retagging.rs
@@ -1,4 +1,3 @@
-//@compile-flags: -Zmiri-retag-fields
 //@error-pattern: which is protected
 struct Newtype<'a>(&'a mut i32);
 
diff --git a/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_option.rs b/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_option.rs
index 7fa9cf77d44b..5a9dc6afba8d 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_option.rs
+++ b/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_option.rs
@@ -1,16 +1,15 @@
 // Make sure that we cannot return a `&mut` that got already invalidated, not even in an `Option`.
-// Due to shallow reborrowing, the error only surfaces when we look into the `Option`.
 fn foo(x: &mut (i32, i32)) -> Option<&mut i32> {
     let xraw = x as *mut (i32, i32);
     let ret = unsafe { &mut (*xraw).1 }; // let-bind to avoid 2phase
     let ret = Some(ret);
     let _val = unsafe { *xraw }; // invalidate xref
-    ret
+    ret //~ ERROR: /retag .* tag does not exist in the borrow stack/
 }
 
 fn main() {
     match foo(&mut (1, 2)) {
-        Some(_x) => {} //~ ERROR: /retag .* tag does not exist in the borrow stack/
+        Some(_x) => {}
         None => {}
     }
 }
diff --git a/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_option.stderr b/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_option.stderr
index 1068c286c62f..c0ff35ebcde3 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_option.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_option.stderr
@@ -1,11 +1,11 @@
 error: Undefined Behavior: trying to retag from <TAG> for Unique permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
   --> $DIR/return_invalid_mut_option.rs:LL:CC
    |
-LL |         Some(_x) => {}
-   |              ^^
-   |              |
-   |              trying to retag from <TAG> for Unique permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
-   |              this error occurs as part of retag at ALLOC[0x4..0x8]
+LL |     ret
+   |     ^^^
+   |     |
+   |     trying to retag from <TAG> for Unique permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
+   |     this error occurs as part of retag at ALLOC[0x4..0x8]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
@@ -13,14 +13,19 @@ help: <TAG> was created by a Unique retag at offsets [0x4..0x8]
   --> $DIR/return_invalid_mut_option.rs:LL:CC
    |
 LL |     let ret = Some(ret);
-   |                    ^^^
+   |               ^^^^^^^^^
 help: <TAG> was later invalidated at offsets [0x0..0x8] by a read access
   --> $DIR/return_invalid_mut_option.rs:LL:CC
    |
 LL |     let _val = unsafe { *xraw }; // invalidate xref
    |                         ^^^^^
    = note: BACKTRACE:
-   = note: inside `main` at $DIR/return_invalid_mut_option.rs:LL:CC
+   = note: inside `foo` at $DIR/return_invalid_mut_option.rs:LL:CC
+note: inside `main` at $DIR/return_invalid_mut_option.rs:LL:CC
+  --> $DIR/return_invalid_mut_option.rs:LL:CC
+   |
+LL |     match foo(&mut (1, 2)) {
+   |           ^^^^^^^^^^^^^^^^
 
 note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace
 
diff --git a/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_tuple.rs b/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_tuple.rs
index c94fef90542f..8fe7f15cab0c 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_tuple.rs
+++ b/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_tuple.rs
@@ -1,12 +1,11 @@
 // Make sure that we cannot return a `&mut` that got already invalidated, not even in a tuple.
-// Due to shallow reborrowing, the error only surfaces when we look into the tuple.
 fn foo(x: &mut (i32, i32)) -> (&mut i32,) {
     let xraw = x as *mut (i32, i32);
     let ret = (unsafe { &mut (*xraw).1 },);
     let _val = unsafe { *xraw }; // invalidate xref
-    ret
+    ret //~ ERROR: /retag .* tag does not exist in the borrow stack/
 }
 
 fn main() {
-    foo(&mut (1, 2)).0; //~ ERROR: /retag .* tag does not exist in the borrow stack/
+    foo(&mut (1, 2)).0;
 }
diff --git a/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_tuple.stderr b/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_tuple.stderr
index 79de9b668cf2..9abf43c29f08 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_tuple.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_tuple.stderr
@@ -1,8 +1,8 @@
 error: Undefined Behavior: trying to retag from <TAG> for Unique permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
   --> $DIR/return_invalid_mut_tuple.rs:LL:CC
    |
-LL |     foo(&mut (1, 2)).0;
-   |     ^^^^^^^^^^^^^^^^^^
+LL |     ret
+   |     ^^^
    |     |
    |     trying to retag from <TAG> for Unique permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
    |     this error occurs as part of retag at ALLOC[0x4..0x8]
@@ -13,14 +13,19 @@ help: <TAG> was created by a Unique retag at offsets [0x4..0x8]
   --> $DIR/return_invalid_mut_tuple.rs:LL:CC
    |
 LL |     let ret = (unsafe { &mut (*xraw).1 },);
-   |                         ^^^^^^^^^^^^^^
+   |               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 help: <TAG> was later invalidated at offsets [0x0..0x8] by a read access
   --> $DIR/return_invalid_mut_tuple.rs:LL:CC
    |
 LL |     let _val = unsafe { *xraw }; // invalidate xref
    |                         ^^^^^
    = note: BACKTRACE:
-   = note: inside `main` at $DIR/return_invalid_mut_tuple.rs:LL:CC
+   = note: inside `foo` at $DIR/return_invalid_mut_tuple.rs:LL:CC
+note: inside `main` at $DIR/return_invalid_mut_tuple.rs:LL:CC
+  --> $DIR/return_invalid_mut_tuple.rs:LL:CC
+   |
+LL |     foo(&mut (1, 2)).0;
+   |     ^^^^^^^^^^^^^^^^
 
 note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace
 
diff --git a/src/tools/miri/tests/fail/stacked_borrows/return_invalid_shr_option.rs b/src/tools/miri/tests/fail/stacked_borrows/return_invalid_shr_option.rs
index 3a028ceed86a..094ce33b9c1f 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/return_invalid_shr_option.rs
+++ b/src/tools/miri/tests/fail/stacked_borrows/return_invalid_shr_option.rs
@@ -1,15 +1,14 @@
 // Make sure that we cannot return a `&` that got already invalidated, not even in an `Option`.
-// Due to shallow reborrowing, the error only surfaces when we look into the `Option`.
 fn foo(x: &mut (i32, i32)) -> Option<&i32> {
     let xraw = x as *mut (i32, i32);
     let ret = Some(unsafe { &(*xraw).1 });
     unsafe { *xraw = (42, 23) }; // unfreeze
-    ret
+    ret //~ ERROR: /retag .* tag does not exist in the borrow stack/
 }
 
 fn main() {
     match foo(&mut (1, 2)) {
-        Some(_x) => {} //~ ERROR: /retag .* tag does not exist in the borrow stack/
+        Some(_x) => {}
         None => {}
     }
 }
diff --git a/src/tools/miri/tests/fail/stacked_borrows/return_invalid_shr_option.stderr b/src/tools/miri/tests/fail/stacked_borrows/return_invalid_shr_option.stderr
index f45456305db2..6066bf89f5d0 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/return_invalid_shr_option.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/return_invalid_shr_option.stderr
@@ -1,11 +1,11 @@
 error: Undefined Behavior: trying to retag from <TAG> for SharedReadOnly permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
   --> $DIR/return_invalid_shr_option.rs:LL:CC
    |
-LL |         Some(_x) => {}
-   |              ^^
-   |              |
-   |              trying to retag from <TAG> for SharedReadOnly permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
-   |              this error occurs as part of retag at ALLOC[0x4..0x8]
+LL |     ret
+   |     ^^^
+   |     |
+   |     trying to retag from <TAG> for SharedReadOnly permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
+   |     this error occurs as part of retag at ALLOC[0x4..0x8]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
@@ -13,14 +13,19 @@ help: <TAG> was created by a SharedReadOnly retag at offsets [0x4..0x8]
   --> $DIR/return_invalid_shr_option.rs:LL:CC
    |
 LL |     let ret = Some(unsafe { &(*xraw).1 });
-   |                             ^^^^^^^^^^
+   |               ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 help: <TAG> was later invalidated at offsets [0x0..0x8] by a write access
   --> $DIR/return_invalid_shr_option.rs:LL:CC
    |
 LL |     unsafe { *xraw = (42, 23) }; // unfreeze
    |              ^^^^^^^^^^^^^^^^
    = note: BACKTRACE:
-   = note: inside `main` at $DIR/return_invalid_shr_option.rs:LL:CC
+   = note: inside `foo` at $DIR/return_invalid_shr_option.rs:LL:CC
+note: inside `main` at $DIR/return_invalid_shr_option.rs:LL:CC
+  --> $DIR/return_invalid_shr_option.rs:LL:CC
+   |
+LL |     match foo(&mut (1, 2)) {
+   |           ^^^^^^^^^^^^^^^^
 
 note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace
 
diff --git a/src/tools/miri/tests/fail/stacked_borrows/return_invalid_shr_tuple.rs b/src/tools/miri/tests/fail/stacked_borrows/return_invalid_shr_tuple.rs
index e4536626dbf2..d0fd53e06aa2 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/return_invalid_shr_tuple.rs
+++ b/src/tools/miri/tests/fail/stacked_borrows/return_invalid_shr_tuple.rs
@@ -1,12 +1,11 @@
 // Make sure that we cannot return a `&` that got already invalidated, not even in a tuple.
-// Due to shallow reborrowing, the error only surfaces when we look into the tuple.
 fn foo(x: &mut (i32, i32)) -> (&i32,) {
     let xraw = x as *mut (i32, i32);
     let ret = (unsafe { &(*xraw).1 },);
     unsafe { *xraw = (42, 23) }; // unfreeze
-    ret
+    ret //~ ERROR: /retag .* tag does not exist in the borrow stack/
 }
 
 fn main() {
-    foo(&mut (1, 2)).0; //~ ERROR: /retag .* tag does not exist in the borrow stack/
+    foo(&mut (1, 2)).0;
 }
diff --git a/src/tools/miri/tests/fail/stacked_borrows/return_invalid_shr_tuple.stderr b/src/tools/miri/tests/fail/stacked_borrows/return_invalid_shr_tuple.stderr
index 2e41f505bb9d..52d365246a74 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/return_invalid_shr_tuple.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/return_invalid_shr_tuple.stderr
@@ -1,8 +1,8 @@
 error: Undefined Behavior: trying to retag from <TAG> for SharedReadOnly permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
   --> $DIR/return_invalid_shr_tuple.rs:LL:CC
    |
-LL |     foo(&mut (1, 2)).0;
-   |     ^^^^^^^^^^^^^^^^^^
+LL |     ret
+   |     ^^^
    |     |
    |     trying to retag from <TAG> for SharedReadOnly permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
    |     this error occurs as part of retag at ALLOC[0x4..0x8]
@@ -13,14 +13,19 @@ help: <TAG> was created by a SharedReadOnly retag at offsets [0x4..0x8]
   --> $DIR/return_invalid_shr_tuple.rs:LL:CC
    |
 LL |     let ret = (unsafe { &(*xraw).1 },);
-   |                         ^^^^^^^^^^
+   |               ^^^^^^^^^^^^^^^^^^^^^^^^
 help: <TAG> was later invalidated at offsets [0x0..0x8] by a write access
   --> $DIR/return_invalid_shr_tuple.rs:LL:CC
    |
 LL |     unsafe { *xraw = (42, 23) }; // unfreeze
    |              ^^^^^^^^^^^^^^^^
    = note: BACKTRACE:
-   = note: inside `main` at $DIR/return_invalid_shr_tuple.rs:LL:CC
+   = note: inside `foo` at $DIR/return_invalid_shr_tuple.rs:LL:CC
+note: inside `main` at $DIR/return_invalid_shr_tuple.rs:LL:CC
+  --> $DIR/return_invalid_shr_tuple.rs:LL:CC
+   |
+LL |     foo(&mut (1, 2)).0;
+   |     ^^^^^^^^^^^^^^^^
 
 note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace
 
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/dyn_alignment.rs b/src/tools/miri/tests/fail/unaligned_pointers/dyn_alignment.rs
index b943c7db7ccd..ca8590cc6b3f 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/dyn_alignment.rs
+++ b/src/tools/miri/tests/fail/unaligned_pointers/dyn_alignment.rs
@@ -7,7 +7,7 @@ struct MuchAlign;
 
 fn main() {
     // Try many times as this might work by chance.
-    for _ in 0..10 {
+    for _ in 0..20 {
         let buf = [0u32; 256];
         // `buf` is sufficiently aligned for `layout.align` on a `dyn Debug`, but not
         // for the actual alignment required by `MuchAlign`.
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/reference_to_packed.rs b/src/tools/miri/tests/fail/unaligned_pointers/reference_to_packed.rs
index 752210dca46e..a807200771d6 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/reference_to_packed.rs
+++ b/src/tools/miri/tests/fail/unaligned_pointers/reference_to_packed.rs
@@ -11,7 +11,7 @@ struct Foo {
 
 fn main() {
     // Try many times as this might work by chance.
-    for _ in 0..10 {
+    for _ in 0..20 {
         let foo = Foo { x: 42, y: 99 };
         let p = &foo.x;
         let i = *p; //~ERROR: alignment 4 is required
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr3.rs b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr3.rs
index 7605dd175a98..3aa8cb492a13 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr3.rs
+++ b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr3.rs
@@ -3,7 +3,7 @@
 
 fn main() {
     // Try many times as this might work by chance.
-    for _ in 0..10 {
+    for _ in 0..20 {
         let x = [2u16, 3, 4, 5]; // Make it big enough so we don't get an out-of-bounds error.
         let x = &x[0] as *const _ as *const *const u8; // cast to ptr-to-ptr, so that we load a ptr
         // This must fail because alignment is violated. Test specifically for loading pointers,
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr4.rs b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr4.rs
index 852febe4c04c..606316120d6e 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr4.rs
+++ b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr4.rs
@@ -6,7 +6,7 @@ fn main() {
     // (This would be missed if u8 allocations are *always* at odd addresses.)
     //
     // Try many times as this might work by chance.
-    for _ in 0..10 {
+    for _ in 0..20 {
         let x = [0u8; 4];
         let ptr = x.as_ptr().wrapping_offset(1).cast::<u16>();
         let _val = unsafe { *ptr }; //~ERROR: but alignment
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr_zst.rs b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr_zst.rs
index 9076581b55bb..eff423759560 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr_zst.rs
+++ b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr_zst.rs
@@ -4,7 +4,7 @@
 
 fn main() {
     // Try many times as this might work by chance.
-    for i in 0..10 {
+    for i in 0..20 {
         let x = i as u8;
         let x = &x as *const _ as *const [u32; 0];
         // This must fail because alignment is violated. Test specifically for loading ZST.
diff --git a/src/tools/miri/tests/pass-dep/concurrency/libc_pthread_cond_isolated.rs b/src/tools/miri/tests/pass-dep/concurrency/libc_pthread_cond_isolated.rs
new file mode 100644
index 000000000000..103ce44006d3
--- /dev/null
+++ b/src/tools/miri/tests/pass-dep/concurrency/libc_pthread_cond_isolated.rs
@@ -0,0 +1,82 @@
+//@ignore-target-windows: No libc on Windows
+//@ignore-target-apple: pthread_condattr_setclock is not supported on MacOS.
+
+/// Test that conditional variable timeouts are working properly
+/// with monotonic clocks even under isolation.
+use std::mem::MaybeUninit;
+use std::time::Instant;
+
+fn test_timed_wait_timeout(clock_id: i32) {
+    unsafe {
+        let mut attr: MaybeUninit<libc::pthread_condattr_t> = MaybeUninit::uninit();
+        assert_eq!(libc::pthread_condattr_init(attr.as_mut_ptr()), 0);
+        assert_eq!(libc::pthread_condattr_setclock(attr.as_mut_ptr(), clock_id), 0);
+
+        let mut cond: MaybeUninit<libc::pthread_cond_t> = MaybeUninit::uninit();
+        assert_eq!(libc::pthread_cond_init(cond.as_mut_ptr(), attr.as_ptr()), 0);
+        assert_eq!(libc::pthread_condattr_destroy(attr.as_mut_ptr()), 0);
+
+        let mut mutex: libc::pthread_mutex_t = libc::PTHREAD_MUTEX_INITIALIZER;
+
+        let mut now_mu: MaybeUninit<libc::timespec> = MaybeUninit::uninit();
+        assert_eq!(libc::clock_gettime(clock_id, now_mu.as_mut_ptr()), 0);
+        let now = now_mu.assume_init();
+        // Waiting for a second... mostly because waiting less requires mich more tricky arithmetic.
+        // FIXME: wait less.
+        let timeout = libc::timespec { tv_sec: now.tv_sec + 1, tv_nsec: now.tv_nsec };
+
+        assert_eq!(libc::pthread_mutex_lock(&mut mutex as *mut _), 0);
+        let current_time = Instant::now();
+        assert_eq!(
+            libc::pthread_cond_timedwait(cond.as_mut_ptr(), &mut mutex as *mut _, &timeout),
+            libc::ETIMEDOUT
+        );
+        let elapsed_time = current_time.elapsed().as_millis();
+        assert!(900 <= elapsed_time && elapsed_time <= 1300);
+
+        // Test calling `pthread_cond_timedwait` again with an already elapsed timeout.
+        assert_eq!(
+            libc::pthread_cond_timedwait(cond.as_mut_ptr(), &mut mutex as *mut _, &timeout),
+            libc::ETIMEDOUT
+        );
+
+        // Test that invalid nanosecond values (above 10^9 or negative) are rejected with the
+        // correct error code.
+        let invalid_timeout_1 = libc::timespec { tv_sec: now.tv_sec + 1, tv_nsec: 1_000_000_000 };
+        assert_eq!(
+            libc::pthread_cond_timedwait(
+                cond.as_mut_ptr(),
+                &mut mutex as *mut _,
+                &invalid_timeout_1
+            ),
+            libc::EINVAL
+        );
+        let invalid_timeout_2 = libc::timespec { tv_sec: now.tv_sec + 1, tv_nsec: -1 };
+        assert_eq!(
+            libc::pthread_cond_timedwait(
+                cond.as_mut_ptr(),
+                &mut mutex as *mut _,
+                &invalid_timeout_2
+            ),
+            libc::EINVAL
+        );
+        // Test that invalid second values (negative) are rejected with the correct error code.
+        let invalid_timeout_3 = libc::timespec { tv_sec: -1, tv_nsec: 0 };
+        assert_eq!(
+            libc::pthread_cond_timedwait(
+                cond.as_mut_ptr(),
+                &mut mutex as *mut _,
+                &invalid_timeout_3
+            ),
+            libc::EINVAL
+        );
+
+        assert_eq!(libc::pthread_mutex_unlock(&mut mutex as *mut _), 0);
+        assert_eq!(libc::pthread_mutex_destroy(&mut mutex as *mut _), 0);
+        assert_eq!(libc::pthread_cond_destroy(cond.as_mut_ptr()), 0);
+    }
+}
+
+fn main() {
+    test_timed_wait_timeout(libc::CLOCK_MONOTONIC);
+}
diff --git a/src/tools/miri/tests/pass-dep/shims/libc-fs-with-isolation.rs b/src/tools/miri/tests/pass-dep/shims/libc-fs-with-isolation.rs
new file mode 100644
index 000000000000..f1838cf64f7f
--- /dev/null
+++ b/src/tools/miri/tests/pass-dep/shims/libc-fs-with-isolation.rs
@@ -0,0 +1,28 @@
+//@ignore-target-windows: no libc on Windows
+//@compile-flags: -Zmiri-isolation-error=warn-nobacktrace
+//@normalize-stderr-test: "(stat(x)?)" -> "$$STAT"
+
+use std::ffi::CString;
+use std::fs;
+use std::io::{Error, ErrorKind};
+
+fn main() {
+    // test `fcntl`
+    unsafe {
+        assert_eq!(libc::fcntl(1, libc::F_DUPFD, 0), -1);
+        assert_eq!(Error::last_os_error().raw_os_error(), Some(libc::EPERM));
+    }
+
+    // test `readlink`
+    let symlink_c_str = CString::new("foo.txt").unwrap();
+    let mut buf = vec![0; "foo_link.txt".len() + 1];
+    unsafe {
+        assert_eq!(libc::readlink(symlink_c_str.as_ptr(), buf.as_mut_ptr(), buf.len()), -1);
+        assert_eq!(Error::last_os_error().raw_os_error(), Some(libc::EACCES));
+    }
+
+    // test `stat`
+    assert_eq!(fs::metadata("foo.txt").unwrap_err().kind(), ErrorKind::PermissionDenied);
+    // check that it is the right kind of `PermissionDenied`
+    assert_eq!(Error::last_os_error().raw_os_error(), Some(libc::EACCES));
+}
diff --git a/src/tools/miri/tests/pass-dep/shims/libc-fs-with-isolation.stderr b/src/tools/miri/tests/pass-dep/shims/libc-fs-with-isolation.stderr
new file mode 100644
index 000000000000..21fcb65243e2
--- /dev/null
+++ b/src/tools/miri/tests/pass-dep/shims/libc-fs-with-isolation.stderr
@@ -0,0 +1,6 @@
+warning: `fcntl` was made to return an error due to isolation
+
+warning: `readlink` was made to return an error due to isolation
+
+warning: `$STAT` was made to return an error due to isolation
+
diff --git a/src/tools/miri/tests/pass-dep/shims/libc-fs.rs b/src/tools/miri/tests/pass-dep/shims/libc-fs.rs
new file mode 100644
index 000000000000..acf16ecb7e06
--- /dev/null
+++ b/src/tools/miri/tests/pass-dep/shims/libc-fs.rs
@@ -0,0 +1,137 @@
+//@ignore-target-windows: no libc on Windows
+//@compile-flags: -Zmiri-disable-isolation
+
+#![feature(io_error_more)]
+#![feature(io_error_uncategorized)]
+
+use std::convert::TryInto;
+use std::ffi::CString;
+use std::fs::{canonicalize, remove_file, File};
+use std::io::{Error, ErrorKind, Write};
+use std::os::unix::ffi::OsStrExt;
+use std::path::PathBuf;
+
+fn main() {
+    test_dup_stdout_stderr();
+    test_canonicalize_too_long();
+    test_readlink();
+    test_file_open_unix_allow_two_args();
+    test_file_open_unix_needs_three_args();
+    test_file_open_unix_extra_third_arg();
+}
+
+fn tmp() -> PathBuf {
+    std::env::var("MIRI_TEMP")
+        .map(|tmp| {
+            // MIRI_TEMP is set outside of our emulated
+            // program, so it may have path separators that don't
+            // correspond to our target platform. We normalize them here
+            // before constructing a `PathBuf`
+
+            #[cfg(windows)]
+            return PathBuf::from(tmp.replace("/", "\\"));
+
+            #[cfg(not(windows))]
+            return PathBuf::from(tmp.replace("\\", "/"));
+        })
+        .unwrap_or_else(|_| std::env::temp_dir())
+}
+
+/// Prepare: compute filename and make sure the file does not exist.
+fn prepare(filename: &str) -> PathBuf {
+    let path = tmp().join(filename);
+    // Clean the paths for robustness.
+    remove_file(&path).ok();
+    path
+}
+
+/// Prepare like above, and also write some initial content to the file.
+fn prepare_with_content(filename: &str, content: &[u8]) -> PathBuf {
+    let path = prepare(filename);
+    let mut file = File::create(&path).unwrap();
+    file.write(content).unwrap();
+    path
+}
+
+fn test_file_open_unix_allow_two_args() {
+    let path = prepare_with_content("test_file_open_unix_allow_two_args.txt", &[]);
+
+    let mut name = path.into_os_string();
+    name.push("\0");
+    let name_ptr = name.as_bytes().as_ptr().cast::<libc::c_char>();
+    let _fd = unsafe { libc::open(name_ptr, libc::O_RDONLY) };
+}
+
+fn test_file_open_unix_needs_three_args() {
+    let path = prepare_with_content("test_file_open_unix_needs_three_args.txt", &[]);
+
+    let mut name = path.into_os_string();
+    name.push("\0");
+    let name_ptr = name.as_bytes().as_ptr().cast::<libc::c_char>();
+    let _fd = unsafe { libc::open(name_ptr, libc::O_CREAT, 0o666) };
+}
+
+fn test_file_open_unix_extra_third_arg() {
+    let path = prepare_with_content("test_file_open_unix_extra_third_arg.txt", &[]);
+
+    let mut name = path.into_os_string();
+    name.push("\0");
+    let name_ptr = name.as_bytes().as_ptr().cast::<libc::c_char>();
+    let _fd = unsafe { libc::open(name_ptr, libc::O_RDONLY, 42) };
+}
+
+fn test_dup_stdout_stderr() {
+    let bytes = b"hello dup fd\n";
+    unsafe {
+        let new_stdout = libc::fcntl(1, libc::F_DUPFD, 0);
+        let new_stderr = libc::fcntl(2, libc::F_DUPFD, 0);
+        libc::write(new_stdout, bytes.as_ptr() as *const libc::c_void, bytes.len());
+        libc::write(new_stderr, bytes.as_ptr() as *const libc::c_void, bytes.len());
+    }
+}
+
+fn test_canonicalize_too_long() {
+    // Make sure we get an error for long paths.
+    let too_long = "x/".repeat(libc::PATH_MAX.try_into().unwrap());
+    assert!(canonicalize(too_long).is_err());
+}
+
+fn test_readlink() {
+    let bytes = b"Hello, World!\n";
+    let path = prepare_with_content("miri_test_fs_link_target.txt", bytes);
+    let expected_path = path.as_os_str().as_bytes();
+
+    let symlink_path = prepare("miri_test_fs_symlink.txt");
+    std::os::unix::fs::symlink(&path, &symlink_path).unwrap();
+
+    // Test that the expected string gets written to a buffer of proper
+    // length, and that a trailing null byte is not written.
+    let symlink_c_str = CString::new(symlink_path.as_os_str().as_bytes()).unwrap();
+    let symlink_c_ptr = symlink_c_str.as_ptr();
+
+    // Make the buf one byte larger than it needs to be,
+    // and check that the last byte is not overwritten.
+    let mut large_buf = vec![0xFF; expected_path.len() + 1];
+    let res =
+        unsafe { libc::readlink(symlink_c_ptr, large_buf.as_mut_ptr().cast(), large_buf.len()) };
+    // Check that the resovled path was properly written into the buf.
+    assert_eq!(&large_buf[..(large_buf.len() - 1)], expected_path);
+    assert_eq!(large_buf.last(), Some(&0xFF));
+    assert_eq!(res, large_buf.len() as isize - 1);
+
+    // Test that the resolved path is truncated if the provided buffer
+    // is too small.
+    let mut small_buf = [0u8; 2];
+    let res =
+        unsafe { libc::readlink(symlink_c_ptr, small_buf.as_mut_ptr().cast(), small_buf.len()) };
+    assert_eq!(small_buf, &expected_path[..small_buf.len()]);
+    assert_eq!(res, small_buf.len() as isize);
+
+    // Test that we report a proper error for a missing path.
+    let bad_path = CString::new("MIRI_MISSING_FILE_NAME").unwrap();
+    let res = unsafe {
+        libc::readlink(bad_path.as_ptr(), small_buf.as_mut_ptr().cast(), small_buf.len())
+    };
+    assert_eq!(res, -1);
+    assert_eq!(Error::last_os_error().kind(), ErrorKind::NotFound);
+}
diff --git a/src/tools/miri/tests/pass-dep/shims/fs.stderr b/src/tools/miri/tests/pass-dep/shims/libc-fs.stderr
similarity index 100%
rename from src/tools/miri/tests/pass-dep/shims/fs.stderr
rename to src/tools/miri/tests/pass-dep/shims/libc-fs.stderr
diff --git a/src/tools/miri/tests/pass-dep/shims/fs.stdout b/src/tools/miri/tests/pass-dep/shims/libc-fs.stdout
similarity index 100%
rename from src/tools/miri/tests/pass-dep/shims/fs.stdout
rename to src/tools/miri/tests/pass-dep/shims/libc-fs.stdout
diff --git a/src/tools/miri/tests/pass-dep/shims/libc-misc.rs b/src/tools/miri/tests/pass-dep/shims/libc-misc.rs
index a883a3d967a3..904ae2fb17f9 100644
--- a/src/tools/miri/tests/pass-dep/shims/libc-misc.rs
+++ b/src/tools/miri/tests/pass-dep/shims/libc-misc.rs
@@ -87,7 +87,7 @@ fn test_posix_realpath_errors() {
     assert_eq!(e.kind(), ErrorKind::NotFound);
 }
 
-#[cfg(any(target_os = "linux"))]
+#[cfg(target_os = "linux")]
 fn test_posix_fadvise() {
     use std::convert::TryInto;
     use std::io::Write;
@@ -115,7 +115,7 @@ fn test_posix_fadvise() {
     assert_eq!(result, 0);
 }
 
-#[cfg(any(target_os = "linux"))]
+#[cfg(target_os = "linux")]
 fn test_sync_file_range() {
     use std::io::Write;
 
@@ -181,7 +181,7 @@ fn test_thread_local_errno() {
 }
 
 /// Tests whether clock support exists at all
-#[cfg(any(target_os = "linux"))]
+#[cfg(target_os = "linux")]
 fn test_clocks() {
     let mut tp = std::mem::MaybeUninit::<libc::timespec>::uninit();
     let is_error = unsafe { libc::clock_gettime(libc::CLOCK_REALTIME, tp.as_mut_ptr()) };
@@ -283,9 +283,6 @@ fn test_posix_mkstemp() {
 }
 
 fn main() {
-    #[cfg(any(target_os = "linux"))]
-    test_posix_fadvise();
-
     test_posix_gettimeofday();
     test_posix_mkstemp();
 
@@ -293,13 +290,14 @@ fn main() {
     test_posix_realpath_noalloc();
     test_posix_realpath_errors();
 
-    #[cfg(any(target_os = "linux"))]
-    test_sync_file_range();
-
     test_thread_local_errno();
 
-    #[cfg(any(target_os = "linux"))]
-    test_clocks();
-
     test_isatty();
+
+    #[cfg(target_os = "linux")]
+    {
+        test_posix_fadvise();
+        test_sync_file_range();
+        test_clocks();
+    }
 }
diff --git a/src/tools/miri/tests/pass-dep/shims/libc-rsfs.stdout b/src/tools/miri/tests/pass-dep/shims/libc-rsfs.stdout
new file mode 100644
index 000000000000..b6fa69e3d5d2
--- /dev/null
+++ b/src/tools/miri/tests/pass-dep/shims/libc-rsfs.stdout
@@ -0,0 +1 @@
+hello dup fd
diff --git a/src/tools/miri/tests/pass-dep/shims/pthreads.rs b/src/tools/miri/tests/pass-dep/shims/pthreads.rs
index d062eda7e90c..09dd92564d39 100644
--- a/src/tools/miri/tests/pass-dep/shims/pthreads.rs
+++ b/src/tools/miri/tests/pass-dep/shims/pthreads.rs
@@ -1,12 +1,16 @@
 //@ignore-target-windows: No libc on Windows
+#![feature(cstr_from_bytes_until_nul)]
+use std::ffi::{CStr, CString};
+use std::thread;
 
 fn main() {
     test_mutex_libc_init_recursive();
     test_mutex_libc_init_normal();
     test_mutex_libc_init_errorcheck();
     test_rwlock_libc_static_initializer();
+    test_named_thread_truncation();
 
-    #[cfg(any(target_os = "linux"))]
+    #[cfg(target_os = "linux")]
     test_mutex_libc_static_initializer_recursive();
 }
 
@@ -125,3 +129,36 @@ fn test_rwlock_libc_static_initializer() {
         assert_eq!(libc::pthread_rwlock_destroy(rw.get()), 0);
     }
 }
+
+fn test_named_thread_truncation() {
+    let long_name = std::iter::once("test_named_thread_truncation")
+        .chain(std::iter::repeat(" yada").take(100))
+        .collect::<String>();
+
+    fn set_thread_name(name: &CStr) -> i32 {
+        #[cfg(target_os = "linux")]
+        return unsafe { libc::pthread_setname_np(libc::pthread_self(), name.as_ptr().cast()) };
+        #[cfg(target_os = "macos")]
+        return unsafe { libc::pthread_setname_np(name.as_ptr().cast()) };
+    }
+
+    let result = thread::Builder::new().name(long_name.clone()).spawn(move || {
+        // Rust remembers the full thread name itself.
+        assert_eq!(thread::current().name(), Some(long_name.as_str()));
+
+        // But the system is limited -- make sure we successfully set a truncation.
+        let mut buf = vec![0u8; long_name.len() + 1];
+        unsafe {
+            libc::pthread_getname_np(libc::pthread_self(), buf.as_mut_ptr().cast(), buf.len())
+        };
+        let cstr = CStr::from_bytes_until_nul(&buf).unwrap();
+        assert!(cstr.to_bytes().len() >= 15); // POSIX seems to promise at least 15 chars
+        assert!(long_name.as_bytes().starts_with(cstr.to_bytes()));
+
+        // Also test directly calling pthread_setname to check its return value.
+        assert_eq!(set_thread_name(&cstr), 0);
+        // But with a too long name it should fail.
+        assert_ne!(set_thread_name(&CString::new(long_name).unwrap()), 0);
+    });
+    result.unwrap().join().unwrap();
+}
diff --git a/src/tools/miri/tests/pass/align.rs b/src/tools/miri/tests/pass/align.rs
index 997abd733922..2b6e83891d6e 100644
--- a/src/tools/miri/tests/pass/align.rs
+++ b/src/tools/miri/tests/pass/align.rs
@@ -22,7 +22,7 @@ fn align_to() {
 
 fn main() {
     // Do this a couple times in a loop because it may work "by chance".
-    for _ in 0..10 {
+    for _ in 0..20 {
         manual_alignment();
         align_to();
     }
diff --git a/src/tools/miri/tests/pass/concurrency/channels.rs b/src/tools/miri/tests/pass/concurrency/channels.rs
index c75c5199bf11..53b57942d76a 100644
--- a/src/tools/miri/tests/pass/concurrency/channels.rs
+++ b/src/tools/miri/tests/pass/concurrency/channels.rs
@@ -1,4 +1,3 @@
-//@ignore-target-windows: Channels on Windows are not supported yet.
 //@compile-flags: -Zmiri-strict-provenance
 
 use std::sync::mpsc::{channel, sync_channel};
diff --git a/src/tools/miri/tests/pass/concurrency/spin_loops_nopreempt.rs b/src/tools/miri/tests/pass/concurrency/spin_loops_nopreempt.rs
index 5d8e2ef5f028..44b16e1ac74d 100644
--- a/src/tools/miri/tests/pass/concurrency/spin_loops_nopreempt.rs
+++ b/src/tools/miri/tests/pass/concurrency/spin_loops_nopreempt.rs
@@ -1,4 +1,3 @@
-//@ignore-target-windows: Channels on Windows are not supported yet.
 // This specifically tests behavior *without* preemption.
 //@compile-flags: -Zmiri-preemption-rate=0
 
diff --git a/src/tools/miri/tests/pass/concurrency/sync.rs b/src/tools/miri/tests/pass/concurrency/sync.rs
index 8bda32bb95a4..19ea6c130bdd 100644
--- a/src/tools/miri/tests/pass/concurrency/sync.rs
+++ b/src/tools/miri/tests/pass/concurrency/sync.rs
@@ -1,4 +1,3 @@
-//@ignore-target-windows: Concurrency on Windows is not supported yet.
 //@compile-flags: -Zmiri-disable-isolation -Zmiri-strict-provenance
 
 use std::sync::{Arc, Barrier, Condvar, Mutex, Once, RwLock};
@@ -225,14 +224,14 @@ fn park_unpark() {
 }
 
 fn main() {
-    check_barriers();
-    check_conditional_variables_notify_one();
-    check_conditional_variables_timed_wait_timeout();
-    check_conditional_variables_timed_wait_notimeout();
     check_mutex();
     check_rwlock_write();
     check_rwlock_read_no_deadlock();
     check_once();
     park_timeout();
     park_unpark();
+    check_barriers();
+    check_conditional_variables_notify_one();
+    check_conditional_variables_timed_wait_timeout();
+    check_conditional_variables_timed_wait_notimeout();
 }
diff --git a/src/tools/miri/tests/pass/concurrency/sync_nopreempt.rs b/src/tools/miri/tests/pass/concurrency/sync_nopreempt.rs
index 3da33fee4c0e..c6cff038f81e 100644
--- a/src/tools/miri/tests/pass/concurrency/sync_nopreempt.rs
+++ b/src/tools/miri/tests/pass/concurrency/sync_nopreempt.rs
@@ -1,4 +1,3 @@
-//@ignore-target-windows: Concurrency on Windows is not supported yet.
 // We are making scheduler assumptions here.
 //@compile-flags: -Zmiri-strict-provenance -Zmiri-preemption-rate=0
 
diff --git a/src/tools/miri/tests/pass/concurrency/thread_park_isolated.rs b/src/tools/miri/tests/pass/concurrency/thread_park_isolated.rs
new file mode 100644
index 000000000000..bf004012e848
--- /dev/null
+++ b/src/tools/miri/tests/pass/concurrency/thread_park_isolated.rs
@@ -0,0 +1,12 @@
+//@ignore-target-apple: park_timeout on macOS uses the system clock
+use std::thread;
+use std::time::{Duration, Instant};
+
+fn main() {
+    let start = Instant::now();
+
+    thread::park_timeout(Duration::from_millis(200));
+
+    // Thanks to deterministic execution, this will wiat *exactly* 200ms (rounded to 1ms).
+    assert!((200..201).contains(&start.elapsed().as_millis()));
+}
diff --git a/src/tools/miri/tests/pass/concurrency/windows_condvar_shared.rs b/src/tools/miri/tests/pass/concurrency/windows_condvar_shared.rs
new file mode 100644
index 000000000000..d89320bfe597
--- /dev/null
+++ b/src/tools/miri/tests/pass/concurrency/windows_condvar_shared.rs
@@ -0,0 +1,227 @@
+//@only-target-windows: Uses win32 api functions
+// We are making scheduler assumptions here.
+//@compile-flags: -Zmiri-preemption-rate=0
+
+use std::ffi::c_void;
+use std::ptr::null_mut;
+use std::thread;
+
+#[derive(Copy, Clone)]
+struct SendPtr<T>(*mut T);
+
+unsafe impl<T> Send for SendPtr<T> {}
+
+extern "system" {
+    fn SleepConditionVariableSRW(
+        condvar: *mut *mut c_void,
+        lock: *mut *mut c_void,
+        timeout: u32,
+        flags: u32,
+    ) -> i32;
+    fn WakeAllConditionVariable(condvar: *mut *mut c_void);
+
+    fn AcquireSRWLockExclusive(lock: *mut *mut c_void);
+    fn AcquireSRWLockShared(lock: *mut *mut c_void);
+    fn ReleaseSRWLockExclusive(lock: *mut *mut c_void);
+    fn ReleaseSRWLockShared(lock: *mut *mut c_void);
+}
+
+const CONDITION_VARIABLE_LOCKMODE_SHARED: u32 = 1;
+const INFINITE: u32 = u32::MAX;
+
+/// threads should be able to reacquire the lock while it is locked by multiple other threads in shared mode
+fn all_shared() {
+    println!("all_shared");
+
+    let mut lock = null_mut();
+    let mut condvar = null_mut();
+
+    let lock_ptr = SendPtr(&mut lock);
+    let condvar_ptr = SendPtr(&mut condvar);
+
+    let mut handles = Vec::with_capacity(10);
+
+    // waiters
+    for i in 0..5 {
+        handles.push(thread::spawn(move || {
+            unsafe {
+                AcquireSRWLockShared(lock_ptr.0);
+            }
+            println!("exclusive waiter {i} locked");
+
+            let r = unsafe {
+                SleepConditionVariableSRW(
+                    condvar_ptr.0,
+                    lock_ptr.0,
+                    INFINITE,
+                    CONDITION_VARIABLE_LOCKMODE_SHARED,
+                )
+            };
+            assert_ne!(r, 0);
+
+            println!("exclusive waiter {i} reacquired lock");
+
+            // unlocking is unnecessary because the lock is never used again
+        }));
+    }
+
+    // ensures each waiter is waiting by this point
+    thread::yield_now();
+
+    // readers
+    for i in 0..5 {
+        handles.push(thread::spawn(move || {
+            unsafe {
+                AcquireSRWLockShared(lock_ptr.0);
+            }
+            println!("reader {i} locked");
+
+            // switch to next reader or main thread
+            thread::yield_now();
+
+            unsafe {
+                ReleaseSRWLockShared(lock_ptr.0);
+            }
+            println!("reader {i} unlocked");
+        }));
+    }
+
+    // ensures each reader has acquired the lock
+    thread::yield_now();
+
+    unsafe {
+        WakeAllConditionVariable(condvar_ptr.0);
+    }
+
+    for handle in handles {
+        handle.join().unwrap();
+    }
+}
+
+// reacquiring a lock should wait until the lock is not exclusively locked
+fn shared_sleep_and_exclusive_lock() {
+    println!("shared_sleep_and_exclusive_lock");
+
+    let mut lock = null_mut();
+    let mut condvar = null_mut();
+
+    let lock_ptr = SendPtr(&mut lock);
+    let condvar_ptr = SendPtr(&mut condvar);
+
+    let mut waiters = Vec::with_capacity(5);
+    for i in 0..5 {
+        waiters.push(thread::spawn(move || {
+            unsafe {
+                AcquireSRWLockShared(lock_ptr.0);
+            }
+            println!("shared waiter {i} locked");
+
+            let r = unsafe {
+                SleepConditionVariableSRW(
+                    condvar_ptr.0,
+                    lock_ptr.0,
+                    INFINITE,
+                    CONDITION_VARIABLE_LOCKMODE_SHARED,
+                )
+            };
+            assert_ne!(r, 0);
+
+            println!("shared waiter {i} reacquired lock");
+
+            // unlocking is unnecessary because the lock is never used again
+        }));
+    }
+
+    // ensures each waiter is waiting by this point
+    thread::yield_now();
+
+    unsafe {
+        AcquireSRWLockExclusive(lock_ptr.0);
+    }
+    println!("main locked");
+
+    unsafe {
+        WakeAllConditionVariable(condvar_ptr.0);
+    }
+
+    // waiters are now waiting for the lock to be unlocked
+    thread::yield_now();
+
+    unsafe {
+        ReleaseSRWLockExclusive(lock_ptr.0);
+    }
+    println!("main unlocked");
+
+    for handle in waiters {
+        handle.join().unwrap();
+    }
+}
+
+// threads reacquiring locks should wait for all locks to be released first
+fn exclusive_sleep_and_shared_lock() {
+    println!("exclusive_sleep_and_shared_lock");
+
+    let mut lock = null_mut();
+    let mut condvar = null_mut();
+
+    let lock_ptr = SendPtr(&mut lock);
+    let condvar_ptr = SendPtr(&mut condvar);
+
+    let mut handles = Vec::with_capacity(10);
+    for i in 0..5 {
+        handles.push(thread::spawn(move || {
+            unsafe {
+                AcquireSRWLockExclusive(lock_ptr.0);
+            }
+
+            println!("exclusive waiter {i} locked");
+
+            let r = unsafe { SleepConditionVariableSRW(condvar_ptr.0, lock_ptr.0, INFINITE, 0) };
+            assert_ne!(r, 0);
+
+            println!("exclusive waiter {i} reacquired lock");
+
+            // switch to next waiter or main thread
+            thread::yield_now();
+
+            unsafe {
+                ReleaseSRWLockExclusive(lock_ptr.0);
+            }
+            println!("exclusive waiter {i} unlocked");
+        }));
+    }
+
+    for i in 0..5 {
+        handles.push(thread::spawn(move || {
+            unsafe {
+                AcquireSRWLockShared(lock_ptr.0);
+            }
+            println!("reader {i} locked");
+
+            // switch to next reader or main thread
+            thread::yield_now();
+
+            unsafe {
+                ReleaseSRWLockShared(lock_ptr.0);
+            }
+            println!("reader {i} unlocked");
+        }));
+    }
+
+    // ensures each reader has acquired the lock
+    thread::yield_now();
+
+    unsafe {
+        WakeAllConditionVariable(condvar_ptr.0);
+    }
+
+    for handle in handles {
+        handle.join().unwrap();
+    }
+}
+
+fn main() {
+    all_shared();
+    shared_sleep_and_exclusive_lock();
+    exclusive_sleep_and_shared_lock();
+}
diff --git a/src/tools/miri/tests/pass/concurrency/windows_condvar_shared.stdout b/src/tools/miri/tests/pass/concurrency/windows_condvar_shared.stdout
new file mode 100644
index 000000000000..918b54668f20
--- /dev/null
+++ b/src/tools/miri/tests/pass/concurrency/windows_condvar_shared.stdout
@@ -0,0 +1,60 @@
+all_shared
+exclusive waiter 0 locked
+exclusive waiter 1 locked
+exclusive waiter 2 locked
+exclusive waiter 3 locked
+exclusive waiter 4 locked
+reader 0 locked
+reader 1 locked
+reader 2 locked
+reader 3 locked
+reader 4 locked
+exclusive waiter 0 reacquired lock
+exclusive waiter 1 reacquired lock
+exclusive waiter 2 reacquired lock
+exclusive waiter 3 reacquired lock
+exclusive waiter 4 reacquired lock
+reader 0 unlocked
+reader 1 unlocked
+reader 2 unlocked
+reader 3 unlocked
+reader 4 unlocked
+shared_sleep_and_exclusive_lock
+shared waiter 0 locked
+shared waiter 1 locked
+shared waiter 2 locked
+shared waiter 3 locked
+shared waiter 4 locked
+main locked
+main unlocked
+shared waiter 0 reacquired lock
+shared waiter 1 reacquired lock
+shared waiter 2 reacquired lock
+shared waiter 3 reacquired lock
+shared waiter 4 reacquired lock
+exclusive_sleep_and_shared_lock
+exclusive waiter 0 locked
+exclusive waiter 1 locked
+exclusive waiter 2 locked
+exclusive waiter 3 locked
+exclusive waiter 4 locked
+reader 0 locked
+reader 1 locked
+reader 2 locked
+reader 3 locked
+reader 4 locked
+reader 0 unlocked
+reader 1 unlocked
+reader 2 unlocked
+reader 3 unlocked
+reader 4 unlocked
+exclusive waiter 0 reacquired lock
+exclusive waiter 0 unlocked
+exclusive waiter 1 reacquired lock
+exclusive waiter 1 unlocked
+exclusive waiter 2 reacquired lock
+exclusive waiter 2 unlocked
+exclusive waiter 3 reacquired lock
+exclusive waiter 3 unlocked
+exclusive waiter 4 reacquired lock
+exclusive waiter 4 unlocked
diff --git a/src/tools/miri/tests/pass/concurrency/windows_init_once.rs b/src/tools/miri/tests/pass/concurrency/windows_init_once.rs
new file mode 100644
index 000000000000..4eb883796205
--- /dev/null
+++ b/src/tools/miri/tests/pass/concurrency/windows_init_once.rs
@@ -0,0 +1,176 @@
+//@only-target-windows: Uses win32 api functions
+// We are making scheduler assumptions here.
+//@compile-flags: -Zmiri-preemption-rate=0
+
+use std::ffi::c_void;
+use std::ptr::null_mut;
+use std::thread;
+
+#[derive(Copy, Clone)]
+struct SendPtr<T>(*mut T);
+
+unsafe impl<T> Send for SendPtr<T> {}
+
+extern "system" {
+    fn InitOnceBeginInitialize(
+        init: *mut *mut c_void,
+        flags: u32,
+        pending: *mut i32,
+        context: *mut c_void,
+    ) -> i32;
+
+    fn InitOnceComplete(init: *mut *mut c_void, flags: u32, context: *mut c_void) -> i32;
+}
+
+const TRUE: i32 = 1;
+const FALSE: i32 = 0;
+
+const INIT_ONCE_INIT_FAILED: u32 = 4;
+
+fn single_thread() {
+    let mut init_once = null_mut();
+    let mut pending = 0;
+
+    unsafe {
+        assert_eq!(InitOnceBeginInitialize(&mut init_once, 0, &mut pending, null_mut()), TRUE);
+        assert_eq!(pending, TRUE);
+
+        assert_eq!(InitOnceComplete(&mut init_once, 0, null_mut()), TRUE);
+
+        assert_eq!(InitOnceBeginInitialize(&mut init_once, 0, &mut pending, null_mut()), TRUE);
+        assert_eq!(pending, FALSE);
+    }
+
+    let mut init_once = null_mut();
+
+    unsafe {
+        assert_eq!(InitOnceBeginInitialize(&mut init_once, 0, &mut pending, null_mut()), TRUE);
+        assert_eq!(pending, TRUE);
+
+        assert_eq!(InitOnceComplete(&mut init_once, INIT_ONCE_INIT_FAILED, null_mut()), TRUE);
+
+        assert_eq!(InitOnceBeginInitialize(&mut init_once, 0, &mut pending, null_mut()), TRUE);
+        assert_eq!(pending, TRUE);
+    }
+}
+
+fn block_until_complete() {
+    let mut init_once = null_mut();
+    let mut pending = 0;
+
+    unsafe {
+        assert_eq!(InitOnceBeginInitialize(&mut init_once, 0, &mut pending, null_mut()), TRUE);
+        assert_eq!(pending, TRUE);
+    }
+
+    let init_once_ptr = SendPtr(&mut init_once);
+
+    let waiter = move || unsafe {
+        let mut pending = 0;
+
+        assert_eq!(InitOnceBeginInitialize(init_once_ptr.0, 0, &mut pending, null_mut()), TRUE);
+        assert_eq!(pending, FALSE);
+
+        println!("finished waiting for initialization");
+    };
+
+    let waiter1 = thread::spawn(waiter);
+    let waiter2 = thread::spawn(waiter);
+
+    // this yield ensures `waiter1` & `waiter2` are blocked on the main thread
+    thread::yield_now();
+
+    println!("completing initialization");
+
+    unsafe {
+        assert_eq!(InitOnceComplete(init_once_ptr.0, 0, null_mut()), TRUE);
+    }
+
+    waiter1.join().unwrap();
+    waiter2.join().unwrap();
+}
+
+fn retry_on_fail() {
+    let mut init_once = null_mut();
+    let mut pending = 0;
+
+    unsafe {
+        assert_eq!(InitOnceBeginInitialize(&mut init_once, 0, &mut pending, null_mut()), TRUE);
+        assert_eq!(pending, TRUE);
+    }
+
+    let init_once_ptr = SendPtr(&mut init_once);
+
+    let waiter = move || unsafe {
+        let mut pending = 0;
+
+        assert_eq!(InitOnceBeginInitialize(init_once_ptr.0, 0, &mut pending, null_mut()), TRUE);
+
+        if pending == 1 {
+            println!("retrying initialization");
+
+            assert_eq!(InitOnceComplete(init_once_ptr.0, 0, null_mut()), TRUE);
+        } else {
+            println!("finished waiting for initialization");
+        }
+    };
+
+    let waiter1 = thread::spawn(waiter);
+    let waiter2 = thread::spawn(waiter);
+
+    // this yield ensures `waiter1` & `waiter2` are blocked on the main thread
+    thread::yield_now();
+
+    println!("failing initialization");
+
+    unsafe {
+        assert_eq!(InitOnceComplete(init_once_ptr.0, INIT_ONCE_INIT_FAILED, null_mut()), TRUE);
+    }
+
+    waiter1.join().unwrap();
+    waiter2.join().unwrap();
+}
+
+fn no_data_race_after_complete() {
+    let mut init_once = null_mut();
+    let mut pending = 0;
+
+    unsafe {
+        assert_eq!(InitOnceBeginInitialize(&mut init_once, 0, &mut pending, null_mut()), TRUE);
+        assert_eq!(pending, TRUE);
+    }
+
+    let init_once_ptr = SendPtr(&mut init_once);
+
+    let mut place = 0;
+    let place_ptr = SendPtr(&mut place);
+
+    let reader = thread::spawn(move || unsafe {
+        let mut pending = 0;
+
+        // this doesn't block because reader only executes after `InitOnceComplete` is called
+        assert_eq!(InitOnceBeginInitialize(init_once_ptr.0, 0, &mut pending, null_mut()), TRUE);
+        assert_eq!(pending, FALSE);
+        // this should not data race
+        place_ptr.0.read()
+    });
+
+    unsafe {
+        // this should not data race
+        place_ptr.0.write(1);
+    }
+
+    unsafe {
+        assert_eq!(InitOnceComplete(init_once_ptr.0, 0, null_mut()), TRUE);
+    }
+
+    // run reader (without preemption, it has not taken a step yet)
+    assert_eq!(reader.join().unwrap(), 1);
+}
+
+fn main() {
+    single_thread();
+    block_until_complete();
+    retry_on_fail();
+    no_data_race_after_complete();
+}
diff --git a/src/tools/miri/tests/pass/concurrency/windows_init_once.stdout b/src/tools/miri/tests/pass/concurrency/windows_init_once.stdout
new file mode 100644
index 000000000000..f3d5aad8edce
--- /dev/null
+++ b/src/tools/miri/tests/pass/concurrency/windows_init_once.stdout
@@ -0,0 +1,6 @@
+completing initialization
+finished waiting for initialization
+finished waiting for initialization
+failing initialization
+retrying initialization
+finished waiting for initialization
diff --git a/src/tools/miri/tests/pass/integer-ops.rs b/src/tools/miri/tests/pass/integer-ops.rs
index 724be9efc9f8..0ec1f8e9c693 100644
--- a/src/tools/miri/tests/pass/integer-ops.rs
+++ b/src/tools/miri/tests/pass/integer-ops.rs
@@ -1,5 +1,4 @@
 //@compile-flags: -Coverflow-checks=off
-#![feature(int_log)]
 #![allow(arithmetic_overflow)]
 
 pub fn main() {
diff --git a/src/tools/miri/tests/pass/issues/issue-miri-1909.rs b/src/tools/miri/tests/pass/issues/issue-miri-1909.rs
new file mode 100644
index 000000000000..ce2114e760a3
--- /dev/null
+++ b/src/tools/miri/tests/pass/issues/issue-miri-1909.rs
@@ -0,0 +1,57 @@
+//@compile-flags: -Zmiri-permissive-provenance
+#![deny(unsafe_op_in_unsafe_fn)]
+//! This does some tricky ptr-int-casting.
+
+use core::alloc::{GlobalAlloc, Layout};
+use std::alloc::System;
+
+/// # Safety
+/// `ptr` must be valid for writes of `len` bytes
+unsafe fn volatile_write_zeroize_mem(ptr: *mut u8, len: usize) {
+    for i in 0..len {
+        // ptr as usize + i can't overlow because `ptr` is valid for writes of `len`
+        let ptr_new: *mut u8 = ((ptr as usize) + i) as *mut u8;
+        // SAFETY: `ptr` is valid for writes of `len` bytes, so `ptr_new` is valid for a
+        // byte write
+        unsafe {
+            core::ptr::write_volatile(ptr_new, 0u8);
+        }
+    }
+}
+
+pub struct ZeroizeAlloc;
+
+unsafe impl GlobalAlloc for ZeroizeAlloc {
+    unsafe fn alloc(&self, layout: Layout) -> *mut u8 {
+        // SAFETY: uphold by caller
+        unsafe { System.alloc(layout) }
+    }
+
+    unsafe fn dealloc(&self, ptr: *mut u8, layout: Layout) {
+        // securely wipe the deallocated memory
+        // SAFETY: `ptr` is valid for writes of `layout.size()` bytes since it was
+        // previously successfully allocated (by the safety assumption on this function)
+        // and not yet deallocated
+        unsafe {
+            volatile_write_zeroize_mem(ptr, layout.size());
+        }
+        // SAFETY: uphold by caller
+        unsafe { System.dealloc(ptr, layout) }
+    }
+
+    unsafe fn alloc_zeroed(&self, layout: Layout) -> *mut u8 {
+        // SAFETY: uphold by caller
+        unsafe { System.alloc_zeroed(layout) }
+    }
+}
+
+#[global_allocator]
+static GLOBAL: ZeroizeAlloc = ZeroizeAlloc;
+
+fn main() {
+    let layout = Layout::new::<[u8; 16]>();
+    let ptr = unsafe { std::alloc::alloc_zeroed(layout) };
+    unsafe {
+        std::alloc::dealloc(ptr, layout);
+    }
+}
diff --git a/src/tools/miri/tests/pass/issues/issue-miri-2433.rs b/src/tools/miri/tests/pass/issues/issue-miri-2433.rs
index de719df0f1f3..a8281d30bac4 100644
--- a/src/tools/miri/tests/pass/issues/issue-miri-2433.rs
+++ b/src/tools/miri/tests/pass/issues/issue-miri-2433.rs
@@ -1,6 +1,8 @@
 #![feature(type_alias_impl_trait)]
 
-trait T { type Item; }
+trait T {
+    type Item;
+}
 
 type Alias<'a> = impl T<Item = &'a ()>;
 
diff --git a/src/tools/miri/tests/pass/no_std.rs b/src/tools/miri/tests/pass/no_std.rs
index 10632c2cce49..eb0e860e68eb 100644
--- a/src/tools/miri/tests/pass/no_std.rs
+++ b/src/tools/miri/tests/pass/no_std.rs
@@ -3,12 +3,32 @@
 // windows tls dtors go through libstd right now, thus this test
 // cannot pass. When windows tls dtors go through the special magic
 // windows linker section, we can run this test on windows again.
-//@ignore-target-windows
+//@ignore-target-windows: no-std not supported on Windows
+
+// Plumbing to let us use `writeln!` to host stdout:
+
+extern "Rust" {
+    fn miri_write_to_stdout(bytes: &[u8]);
+}
+
+struct Host;
+
+use core::fmt::Write;
+
+impl Write for Host {
+    fn write_str(&mut self, s: &str) -> core::fmt::Result {
+        unsafe {
+            miri_write_to_stdout(s.as_bytes());
+        }
+        Ok(())
+    }
+}
+
+// Aaaand the test:
 
 #[start]
 fn start(_: isize, _: *const *const u8) -> isize {
-    for _ in 0..10 {}
-
+    writeln!(Host, "hello, world!").unwrap();
     0
 }
 
diff --git a/src/tools/miri/tests/pass/no_std.stdout b/src/tools/miri/tests/pass/no_std.stdout
new file mode 100644
index 000000000000..270c611ee72c
--- /dev/null
+++ b/src/tools/miri/tests/pass/no_std.stdout
@@ -0,0 +1 @@
+hello, world!
diff --git a/src/tools/miri/tests/pass/panic/concurrent-panic.rs b/src/tools/miri/tests/pass/panic/concurrent-panic.rs
index 342269c6acbe..776bc2057f35 100644
--- a/src/tools/miri/tests/pass/panic/concurrent-panic.rs
+++ b/src/tools/miri/tests/pass/panic/concurrent-panic.rs
@@ -1,4 +1,3 @@
-//@ignore-target-windows: Condvars on Windows are not supported yet.
 // We are making scheduler assumptions here.
 //@compile-flags: -Zmiri-preemption-rate=0
 
diff --git a/src/tools/miri/tests/pass/shims/env/current_exe.rs b/src/tools/miri/tests/pass/shims/env/current_exe.rs
index 15ea6a52b7b6..3f1153d265d7 100644
--- a/src/tools/miri/tests/pass/shims/env/current_exe.rs
+++ b/src/tools/miri/tests/pass/shims/env/current_exe.rs
@@ -1,4 +1,4 @@
-//@ignore-target-windows
+//@ignore-target-windows: current_exe not supported on Windows
 //@only-on-host: the Linux std implementation opens /proc/self/exe, which doesn't work cross-target
 //@compile-flags: -Zmiri-disable-isolation
 use std::env;
diff --git a/src/tools/miri/tests/pass-dep/shims/fs_with_isolation.rs b/src/tools/miri/tests/pass/shims/fs-with-isolation.rs
similarity index 62%
rename from src/tools/miri/tests/pass-dep/shims/fs_with_isolation.rs
rename to src/tools/miri/tests/pass/shims/fs-with-isolation.rs
index f5420dbc5538..8fa683085b98 100644
--- a/src/tools/miri/tests/pass-dep/shims/fs_with_isolation.rs
+++ b/src/tools/miri/tests/pass/shims/fs-with-isolation.rs
@@ -2,21 +2,14 @@
 //@compile-flags: -Zmiri-isolation-error=warn-nobacktrace
 //@normalize-stderr-test: "(stat(x)?)" -> "$$STAT"
 
-use std::ffi::CString;
 use std::fs::{self, File};
-use std::io::{Error, ErrorKind};
+use std::io::ErrorKind;
 use std::os::unix;
 
 fn main() {
     // test `open`
     assert_eq!(File::create("foo.txt").unwrap_err().kind(), ErrorKind::PermissionDenied);
 
-    // test `fcntl`
-    unsafe {
-        assert_eq!(libc::fcntl(1, libc::F_DUPFD, 0), -1);
-        assert_eq!(Error::last_os_error().raw_os_error(), Some(libc::EPERM));
-    }
-
     // test `unlink`
     assert_eq!(fs::remove_file("foo.txt").unwrap_err().kind(), ErrorKind::PermissionDenied);
 
@@ -26,17 +19,8 @@ fn main() {
         ErrorKind::PermissionDenied
     );
 
-    // test `readlink`
-    let symlink_c_str = CString::new("foo.txt").unwrap();
-    let mut buf = vec![0; "foo_link.txt".len() + 1];
-    unsafe {
-        assert_eq!(libc::readlink(symlink_c_str.as_ptr(), buf.as_mut_ptr(), buf.len()), -1);
-        assert_eq!(Error::last_os_error().raw_os_error(), Some(libc::EACCES));
-    }
-
     // test `stat`
     assert_eq!(fs::metadata("foo.txt").unwrap_err().kind(), ErrorKind::PermissionDenied);
-    assert_eq!(Error::last_os_error().raw_os_error(), Some(libc::EACCES));
 
     // test `rename`
     assert_eq!(fs::rename("a.txt", "b.txt").unwrap_err().kind(), ErrorKind::PermissionDenied);
@@ -49,5 +33,4 @@ fn main() {
 
     // test `opendir`
     assert_eq!(fs::read_dir("foo/bar").unwrap_err().kind(), ErrorKind::PermissionDenied);
-    assert_eq!(Error::last_os_error().raw_os_error(), Some(libc::EACCES));
 }
diff --git a/src/tools/miri/tests/pass-dep/shims/fs_with_isolation.stderr b/src/tools/miri/tests/pass/shims/fs-with-isolation.stderr
similarity index 79%
rename from src/tools/miri/tests/pass-dep/shims/fs_with_isolation.stderr
rename to src/tools/miri/tests/pass/shims/fs-with-isolation.stderr
index ad75e42831b0..452c5b9b772a 100644
--- a/src/tools/miri/tests/pass-dep/shims/fs_with_isolation.stderr
+++ b/src/tools/miri/tests/pass/shims/fs-with-isolation.stderr
@@ -1,13 +1,9 @@
 warning: `open` was made to return an error due to isolation
 
-warning: `fcntl` was made to return an error due to isolation
-
 warning: `unlink` was made to return an error due to isolation
 
 warning: `symlink` was made to return an error due to isolation
 
-warning: `readlink` was made to return an error due to isolation
-
 warning: `$STAT` was made to return an error due to isolation
 
 warning: `rename` was made to return an error due to isolation
diff --git a/src/tools/miri/tests/pass-dep/shims/fs.rs b/src/tools/miri/tests/pass/shims/fs.rs
similarity index 76%
rename from src/tools/miri/tests/pass-dep/shims/fs.rs
rename to src/tools/miri/tests/pass/shims/fs.rs
index e573d330aa4a..65cf6fe66ba5 100644
--- a/src/tools/miri/tests/pass-dep/shims/fs.rs
+++ b/src/tools/miri/tests/pass/shims/fs.rs
@@ -3,14 +3,15 @@
 
 #![feature(io_error_more)]
 #![feature(io_error_uncategorized)]
+#![feature(is_terminal)]
 
 use std::collections::HashMap;
-use std::ffi::{CString, OsString};
+use std::ffi::OsString;
 use std::fs::{
-    create_dir, read_dir, read_link, remove_dir, remove_dir_all, remove_file, rename, File,
-    OpenOptions,
+    canonicalize, create_dir, read_dir, read_link, remove_dir, remove_dir_all, remove_file, rename,
+    File, OpenOptions,
 };
-use std::io::{Error, ErrorKind, Read, Result, Seek, SeekFrom, Write};
+use std::io::{Error, ErrorKind, IsTerminal, Read, Result, Seek, SeekFrom, Write};
 use std::path::{Path, PathBuf};
 
 fn main() {
@@ -26,13 +27,7 @@ fn main() {
     test_rename();
     test_directory();
     test_canonicalize();
-    test_dup_stdout_stderr();
     test_from_raw_os_error();
-
-    // These all require unix, if the test is changed to no longer `ignore-windows`, move these to a unix test
-    test_file_open_unix_allow_two_args();
-    test_file_open_unix_needs_three_args();
-    test_file_open_unix_extra_third_arg();
 }
 
 fn tmp() -> PathBuf {
@@ -97,43 +92,12 @@ fn test_file() {
     file.read_to_end(&mut contents).unwrap();
     assert_eq!(bytes, contents.as_slice());
 
+    assert!(!file.is_terminal());
+
     // Removing file should succeed.
     remove_file(&path).unwrap();
 }
 
-fn test_file_open_unix_allow_two_args() {
-    use std::os::unix::ffi::OsStrExt;
-
-    let path = prepare_with_content("test_file_open_unix_allow_two_args.txt", &[]);
-
-    let mut name = path.into_os_string();
-    name.push("\0");
-    let name_ptr = name.as_bytes().as_ptr().cast::<libc::c_char>();
-    let _fd = unsafe { libc::open(name_ptr, libc::O_RDONLY) };
-}
-
-fn test_file_open_unix_needs_three_args() {
-    use std::os::unix::ffi::OsStrExt;
-
-    let path = prepare_with_content("test_file_open_unix_needs_three_args.txt", &[]);
-
-    let mut name = path.into_os_string();
-    name.push("\0");
-    let name_ptr = name.as_bytes().as_ptr().cast::<libc::c_char>();
-    let _fd = unsafe { libc::open(name_ptr, libc::O_CREAT, 0o666) };
-}
-
-fn test_file_open_unix_extra_third_arg() {
-    use std::os::unix::ffi::OsStrExt;
-
-    let path = prepare_with_content("test_file_open_unix_extra_third_arg.txt", &[]);
-
-    let mut name = path.into_os_string();
-    name.push("\0");
-    let name_ptr = name.as_bytes().as_ptr().cast::<libc::c_char>();
-    let _fd = unsafe { libc::open(name_ptr, libc::O_RDONLY, 42) };
-}
-
 fn test_file_clone() {
     let bytes = b"Hello, World!\n";
     let path = prepare_with_content("miri_test_fs_file_clone.txt", bytes);
@@ -279,46 +243,6 @@ fn test_symlink() {
     symlink_file.read_to_end(&mut contents).unwrap();
     assert_eq!(bytes, contents.as_slice());
 
-    #[cfg(unix)]
-    {
-        use std::os::unix::ffi::OsStrExt;
-
-        let expected_path = path.as_os_str().as_bytes();
-
-        // Test that the expected string gets written to a buffer of proper
-        // length, and that a trailing null byte is not written.
-        let symlink_c_str = CString::new(symlink_path.as_os_str().as_bytes()).unwrap();
-        let symlink_c_ptr = symlink_c_str.as_ptr();
-
-        // Make the buf one byte larger than it needs to be,
-        // and check that the last byte is not overwritten.
-        let mut large_buf = vec![0xFF; expected_path.len() + 1];
-        let res = unsafe {
-            libc::readlink(symlink_c_ptr, large_buf.as_mut_ptr().cast(), large_buf.len())
-        };
-        // Check that the resovled path was properly written into the buf.
-        assert_eq!(&large_buf[..(large_buf.len() - 1)], expected_path);
-        assert_eq!(large_buf.last(), Some(&0xFF));
-        assert_eq!(res, large_buf.len() as isize - 1);
-
-        // Test that the resolved path is truncated if the provided buffer
-        // is too small.
-        let mut small_buf = [0u8; 2];
-        let res = unsafe {
-            libc::readlink(symlink_c_ptr, small_buf.as_mut_ptr().cast(), small_buf.len())
-        };
-        assert_eq!(small_buf, &expected_path[..small_buf.len()]);
-        assert_eq!(res, small_buf.len() as isize);
-
-        // Test that we report a proper error for a missing path.
-        let bad_path = CString::new("MIRI_MISSING_FILE_NAME").unwrap();
-        let res = unsafe {
-            libc::readlink(bad_path.as_ptr(), small_buf.as_mut_ptr().cast(), small_buf.len())
-        };
-        assert_eq!(res, -1);
-        assert_eq!(Error::last_os_error().kind(), ErrorKind::NotFound);
-    }
-
     // Test that metadata of a symbolic link (i.e., the file it points to) is correct.
     check_metadata(bytes, &symlink_path).unwrap();
     // Test that the metadata of a symbolic link is correct when not following it.
@@ -369,7 +293,6 @@ fn test_rename() {
 }
 
 fn test_canonicalize() {
-    use std::fs::canonicalize;
     let dir_path = prepare_dir("miri_test_fs_dir");
     create_dir(&dir_path).unwrap();
     let path = dir_path.join("test_file");
@@ -379,11 +302,6 @@ fn test_canonicalize() {
     assert_eq!(p.to_string_lossy().find('.'), None);
 
     remove_dir_all(&dir_path).unwrap();
-
-    // Make sure we get an error for long paths.
-    use std::convert::TryInto;
-    let too_long = "x/".repeat(libc::PATH_MAX.try_into().unwrap());
-    assert!(canonicalize(too_long).is_err());
 }
 
 fn test_directory() {
@@ -440,16 +358,6 @@ fn test_directory() {
     remove_dir_all(&dir_path).unwrap();
 }
 
-fn test_dup_stdout_stderr() {
-    let bytes = b"hello dup fd\n";
-    unsafe {
-        let new_stdout = libc::fcntl(1, libc::F_DUPFD, 0);
-        let new_stderr = libc::fcntl(2, libc::F_DUPFD, 0);
-        libc::write(new_stdout, bytes.as_ptr() as *const libc::c_void, bytes.len());
-        libc::write(new_stderr, bytes.as_ptr() as *const libc::c_void, bytes.len());
-    }
-}
-
 fn test_from_raw_os_error() {
     let code = 6; // not a code that std or Miri know
     let error = Error::from_raw_os_error(code);
diff --git a/src/tools/miri/tests/pass/shims/io.rs b/src/tools/miri/tests/pass/shims/io.rs
new file mode 100644
index 000000000000..4d43549a930b
--- /dev/null
+++ b/src/tools/miri/tests/pass/shims/io.rs
@@ -0,0 +1,9 @@
+#![feature(is_terminal)]
+
+use std::io::IsTerminal;
+
+fn main() {
+    // We can't really assume that this is truly a terminal, and anyway on Windows Miri will always
+    // return `false` here, but we can check that the call succeeds.
+    std::io::stdout().is_terminal();
+}
diff --git a/src/tools/miri/tests/pass/shims/ptr_mask.rs b/src/tools/miri/tests/pass/shims/ptr_mask.rs
new file mode 100644
index 000000000000..fb8bb6b13dbc
--- /dev/null
+++ b/src/tools/miri/tests/pass/shims/ptr_mask.rs
@@ -0,0 +1,18 @@
+#![feature(ptr_mask)]
+#![feature(strict_provenance)]
+
+fn main() {
+    let v: u32 = 0xABCDABCD;
+    let ptr: *const u32 = &v;
+
+    // u32 is 4 aligned,
+    // so the lower `log2(4) = 2` bits of the address are always 0
+    assert_eq!(ptr.addr() & 0b11, 0);
+
+    let tagged_ptr = ptr.map_addr(|a| a | 0b11);
+    let tag = tagged_ptr.addr() & 0b11;
+    let masked_ptr = tagged_ptr.mask(!0b11);
+
+    assert_eq!(tag, 0b11);
+    assert_eq!(unsafe { *masked_ptr }, 0xABCDABCD);
+}
diff --git a/src/tools/miri/tests/pass/shims/sleep_long.rs b/src/tools/miri/tests/pass/shims/sleep_long.rs
index dd4a1843942c..c94f63a54274 100644
--- a/src/tools/miri/tests/pass/shims/sleep_long.rs
+++ b/src/tools/miri/tests/pass/shims/sleep_long.rs
@@ -1,4 +1,3 @@
-//@ignore-target-windows: no threads nor sleep on Windows
 //@compile-flags: -Zmiri-ignore-leaks -Zmiri-disable-isolation
 use std::sync::{Arc, Mutex};
 use std::thread;
diff --git a/src/tools/miri/tests/pass/stacked-borrows/no_field_retagging.rs b/src/tools/miri/tests/pass/stacked-borrows/no_field_retagging.rs
new file mode 100644
index 000000000000..48fc8e8668ce
--- /dev/null
+++ b/src/tools/miri/tests/pass/stacked-borrows/no_field_retagging.rs
@@ -0,0 +1,19 @@
+//@compile-flags: -Zmiri-retag-fields=none
+
+struct Newtype<'a>(&'a mut i32);
+
+fn dealloc_while_running(_n: Newtype<'_>, dealloc: impl FnOnce()) {
+    dealloc();
+}
+
+// Make sure that we do *not* retag the fields of `Newtype`.
+fn main() {
+    let ptr = Box::into_raw(Box::new(0i32));
+    #[rustfmt::skip] // I like my newlines
+    unsafe {
+        dealloc_while_running(
+            Newtype(&mut *ptr),
+            || drop(Box::from_raw(ptr)),
+        )
+    };
+}
diff --git a/src/tools/miri/tests/pass/stacked-borrows/non_scalar_field_retagging.rs b/src/tools/miri/tests/pass/stacked-borrows/non_scalar_field_retagging.rs
new file mode 100644
index 000000000000..ddedc19c9998
--- /dev/null
+++ b/src/tools/miri/tests/pass/stacked-borrows/non_scalar_field_retagging.rs
@@ -0,0 +1,19 @@
+//@compile-flags: -Zmiri-retag-fields=scalar
+
+struct Newtype<'a>(&'a mut i32, i32, i32);
+
+fn dealloc_while_running(_n: Newtype<'_>, dealloc: impl FnOnce()) {
+    dealloc();
+}
+
+// Make sure that with -Zmiri-retag-fields=scalar, we do *not* retag the fields of `Newtype`.
+fn main() {
+    let ptr = Box::into_raw(Box::new(0i32));
+    #[rustfmt::skip] // I like my newlines
+    unsafe {
+        dealloc_while_running(
+            Newtype(&mut *ptr, 0, 0),
+            || drop(Box::from_raw(ptr)),
+        )
+    };
+}
diff --git a/src/tools/miri/tests/pass/stacked-borrows/stack-printing.rs b/src/tools/miri/tests/pass/stacked-borrows/stack-printing.rs
new file mode 100644
index 000000000000..3ca937ae13db
--- /dev/null
+++ b/src/tools/miri/tests/pass/stacked-borrows/stack-printing.rs
@@ -0,0 +1,46 @@
+//@compile-flags: -Zmiri-permissive-provenance
+#![feature(strict_provenance)]
+use std::{
+    alloc::{self, Layout},
+    mem::ManuallyDrop,
+};
+
+extern "Rust" {
+    fn miri_get_alloc_id(ptr: *const u8) -> u64;
+    fn miri_print_borrow_stacks(alloc_id: u64);
+}
+
+fn get_alloc_id(ptr: *const u8) -> u64 {
+    unsafe { miri_get_alloc_id(ptr) }
+}
+
+fn print_borrow_stacks(alloc_id: u64) {
+    unsafe { miri_print_borrow_stacks(alloc_id) }
+}
+
+fn main() {
+    let ptr = unsafe { alloc::alloc(Layout::new::<u8>()) };
+    let alloc_id = get_alloc_id(ptr);
+    print_borrow_stacks(alloc_id);
+
+    assert!(!ptr.is_null());
+    print_borrow_stacks(alloc_id);
+
+    unsafe { *ptr = 42 };
+    print_borrow_stacks(alloc_id);
+
+    let _b = unsafe { ManuallyDrop::new(Box::from_raw(ptr)) };
+    print_borrow_stacks(alloc_id);
+
+    let _ptr = unsafe { &*ptr };
+    print_borrow_stacks(alloc_id);
+
+    // Create an unknown bottom, and print it
+    let ptr = ptr as usize as *mut u8;
+    unsafe {
+        *ptr = 5;
+    }
+    print_borrow_stacks(alloc_id);
+
+    unsafe { alloc::dealloc(ptr, Layout::new::<u8>()) };
+}
diff --git a/src/tools/miri/tests/pass/stacked-borrows/stack-printing.stdout b/src/tools/miri/tests/pass/stacked-borrows/stack-printing.stdout
new file mode 100644
index 000000000000..296339e73845
--- /dev/null
+++ b/src/tools/miri/tests/pass/stacked-borrows/stack-printing.stdout
@@ -0,0 +1,6 @@
+0..1: [ SharedReadWrite<TAG> ]
+0..1: [ SharedReadWrite<TAG> ]
+0..1: [ SharedReadWrite<TAG> ]
+0..1: [ SharedReadWrite<TAG> Unique<TAG> Unique<TAG> Unique<TAG> Unique<TAG> Unique<TAG> Unique<TAG> Unique<TAG> ]
+0..1: [ SharedReadWrite<TAG> Disabled<TAG> Disabled<TAG> Disabled<TAG> Disabled<TAG> Disabled<TAG> Disabled<TAG> Disabled<TAG> SharedReadOnly<TAG> ]
+0..1: [ unknown-bottom(..<TAG>) ]
diff --git a/src/tools/miri/tests/pass/stacked-borrows/unknown-bottom-gc.rs b/src/tools/miri/tests/pass/stacked-borrows/unknown-bottom-gc.rs
new file mode 100644
index 000000000000..e62ee528686d
--- /dev/null
+++ b/src/tools/miri/tests/pass/stacked-borrows/unknown-bottom-gc.rs
@@ -0,0 +1,21 @@
+//@compile-flags: -Zmiri-permissive-provenance
+#![feature(strict_provenance)]
+
+use std::ptr;
+
+fn main() {
+    let mut v = 1u8;
+    let ptr = &mut v as *mut u8;
+
+    // Expose the allocation and use the exposed pointer, creating an unknown bottom
+    unsafe {
+        let p: *mut u8 = ptr::from_exposed_addr::<u8>(ptr.expose_addr()) as *mut u8;
+        *p = 1;
+    }
+
+    // Pile on a lot of SharedReadOnly at the top of the stack
+    let r = &v;
+    for _ in 0..1024 {
+        let _x = &*r;
+    }
+}
diff --git a/src/tools/miri/tests/pass/threadleak_ignored.rs b/src/tools/miri/tests/pass/threadleak_ignored.rs
index 99bac7aa42a8..a5f81573e963 100644
--- a/src/tools/miri/tests/pass/threadleak_ignored.rs
+++ b/src/tools/miri/tests/pass/threadleak_ignored.rs
@@ -1,6 +1,4 @@
-//@ignore-target-windows: Channels on Windows are not supported yet.
-// FIXME: disallow preemption to work around https://github.com/rust-lang/rust/issues/55005
-//@compile-flags: -Zmiri-ignore-leaks -Zmiri-preemption-rate=0
+//@compile-flags: -Zmiri-ignore-leaks
 
 //! Test that leaking threads works, and that their destructors are not executed.
 
diff --git a/src/tools/miropt-test-tools/Cargo.toml b/src/tools/miropt-test-tools/Cargo.toml
new file mode 100644
index 000000000000..8589a44cf1ba
--- /dev/null
+++ b/src/tools/miropt-test-tools/Cargo.toml
@@ -0,0 +1,7 @@
+[package]
+name = "miropt-test-tools"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+regex = "1.0"
diff --git a/src/tools/miropt-test-tools/src/lib.rs b/src/tools/miropt-test-tools/src/lib.rs
new file mode 100644
index 000000000000..96819d3547b2
--- /dev/null
+++ b/src/tools/miropt-test-tools/src/lib.rs
@@ -0,0 +1,70 @@
+use std::fs;
+
+pub struct MiroptTestFiles {
+    pub expected_file: std::path::PathBuf,
+    pub from_file: String,
+    pub to_file: Option<String>,
+}
+
+pub fn files_for_miropt_test(testfile: &std::path::Path, bit_width: u32) -> Vec<MiroptTestFiles> {
+    let mut out = Vec::new();
+    let test_file_contents = fs::read_to_string(&testfile).unwrap();
+
+    let test_dir = testfile.parent().unwrap();
+    let test_crate = testfile.file_stem().unwrap().to_str().unwrap().replace("-", "_");
+
+    let bit_width = if test_file_contents.lines().any(|l| l == "// EMIT_MIR_FOR_EACH_BIT_WIDTH") {
+        format!(".{}bit", bit_width)
+    } else {
+        String::new()
+    };
+
+    for l in test_file_contents.lines() {
+        if l.starts_with("// EMIT_MIR ") {
+            let test_name = l.trim_start_matches("// EMIT_MIR ").trim();
+            let mut test_names = test_name.split(' ');
+            // sometimes we specify two files so that we get a diff between the two files
+            let test_name = test_names.next().unwrap();
+            let mut expected_file;
+            let from_file;
+            let to_file;
+
+            if test_name.ends_with(".diff") {
+                let trimmed = test_name.trim_end_matches(".diff");
+                let test_against = format!("{}.after.mir", trimmed);
+                from_file = format!("{}.before.mir", trimmed);
+                expected_file = format!("{}{}.diff", trimmed, bit_width);
+                assert!(test_names.next().is_none(), "two mir pass names specified for MIR diff");
+                to_file = Some(test_against);
+            } else if let Some(first_pass) = test_names.next() {
+                let second_pass = test_names.next().unwrap();
+                assert!(test_names.next().is_none(), "three mir pass names specified for MIR diff");
+                expected_file =
+                    format!("{}{}.{}-{}.diff", test_name, bit_width, first_pass, second_pass);
+                let second_file = format!("{}.{}.mir", test_name, second_pass);
+                from_file = format!("{}.{}.mir", test_name, first_pass);
+                to_file = Some(second_file);
+            } else {
+                let ext_re = regex::Regex::new(r#"(\.(mir|dot|html))$"#).unwrap();
+                let cap = ext_re
+                    .captures_iter(test_name)
+                    .next()
+                    .expect("test_name has an invalid extension");
+                let extension = cap.get(1).unwrap().as_str();
+                expected_file =
+                    format!("{}{}{}", test_name.trim_end_matches(extension), bit_width, extension,);
+                from_file = test_name.to_string();
+                assert!(test_names.next().is_none(), "two mir pass names specified for MIR dump");
+                to_file = None;
+            };
+            if !expected_file.starts_with(&test_crate) {
+                expected_file = format!("{}.{}", test_crate, expected_file);
+            }
+            let expected_file = test_dir.join(expected_file);
+
+            out.push(MiroptTestFiles { expected_file, from_file, to_file });
+        }
+    }
+
+    out
+}
diff --git a/src/tools/remote-test-server/src/main.rs b/src/tools/remote-test-server/src/main.rs
index ec992da68121..8e7c39e72b68 100644
--- a/src/tools/remote-test-server/src/main.rs
+++ b/src/tools/remote-test-server/src/main.rs
@@ -39,6 +39,8 @@ macro_rules! t {
 }
 
 static TEST: AtomicUsize = AtomicUsize::new(0);
+const RETRY_INTERVAL: u64 = 1;
+const NUMBER_OF_RETRIES: usize = 5;
 
 #[derive(Copy, Clone)]
 struct Config {
@@ -115,7 +117,7 @@ fn main() {
     let config = Config::parse_args();
     println!("starting test server");
 
-    let listener = t!(TcpListener::bind(config.bind));
+    let listener = bind_socket(config.bind);
     let (work, tmp): (PathBuf, PathBuf) = if cfg!(target_os = "android") {
         ("/data/local/tmp/work".into(), "/data/local/tmp/work/tmp".into())
     } else {
@@ -159,6 +161,16 @@ fn main() {
     }
 }
 
+fn bind_socket(addr: SocketAddr) -> TcpListener {
+    for _ in 0..(NUMBER_OF_RETRIES - 1) {
+        if let Ok(x) = TcpListener::bind(addr) {
+            return x;
+        }
+        std::thread::sleep(std::time::Duration::from_secs(RETRY_INTERVAL));
+    }
+    TcpListener::bind(addr).unwrap()
+}
+
 fn handle_push(socket: TcpStream, work: &Path, config: Config) {
     let mut reader = BufReader::new(socket);
     let dst = recv(&work, &mut reader);
diff --git a/src/tools/rust-analyzer/.github/ISSUE_TEMPLATE/bug_report.md b/src/tools/rust-analyzer/.github/ISSUE_TEMPLATE/bug_report.md
index a038dce3248a..c2e21933c9a6 100644
--- a/src/tools/rust-analyzer/.github/ISSUE_TEMPLATE/bug_report.md
+++ b/src/tools/rust-analyzer/.github/ISSUE_TEMPLATE/bug_report.md
@@ -13,8 +13,7 @@ Forum for questions: https://users.rust-lang.org/c/ide/14
 
 Before submitting, please make sure that you're not running into one of these known issues:
 
- 1. extension doesn't load in VSCodium: #11080
- 2. on-the-fly diagnostics are mostly unimplemented (`cargo check` diagnostics will be shown when saving a file): #3107
+ 1. on-the-fly diagnostics are mostly unimplemented (`cargo check` diagnostics will be shown when saving a file): #3107
 
 Otherwise please try to provide information which will help us to fix the issue faster. Minimal reproducible examples with few dependencies are especially lovely <3.
 -->
diff --git a/src/tools/rust-analyzer/.github/ISSUE_TEMPLATE/critical_nightly_regression.md b/src/tools/rust-analyzer/.github/ISSUE_TEMPLATE/critical_nightly_regression.md
index a0b1627d7e2e..ad220ff65ca1 100644
--- a/src/tools/rust-analyzer/.github/ISSUE_TEMPLATE/critical_nightly_regression.md
+++ b/src/tools/rust-analyzer/.github/ISSUE_TEMPLATE/critical_nightly_regression.md
@@ -2,8 +2,8 @@
 name: Critical Nightly Regression
 about: You are using nightly rust-analyzer and the latest version is unusable.
 title: ''
-labels: ''
-assignees: 'matklad'
+labels: 'Broken Window'
+assignees: ''
 
 ---
 
@@ -14,4 +14,3 @@ Please try to provide information which will help us to fix the issue faster. Mi
 -->
 
 This is a serious regression in nightly and it's important to fix it before the next release.
-@matklad, please take a look.
diff --git a/src/tools/rust-analyzer/.github/workflows/publish.yml b/src/tools/rust-analyzer/.github/workflows/publish.yml
index a4497f49e3c2..73e62ab32c6c 100644
--- a/src/tools/rust-analyzer/.github/workflows/publish.yml
+++ b/src/tools/rust-analyzer/.github/workflows/publish.yml
@@ -2,8 +2,8 @@ name: publish
 on:
   workflow_dispatch: # We can add version input when 1.0 is released and scheduled releases are removed
 
-#   schedule:
-#     - cron: "0 0 * * *" # midnight UTC
+  #   schedule:
+  #     - cron: "0 0 * * *" # midnight UTC
 
   push:
     branches:
@@ -50,5 +50,7 @@ jobs:
           cargo workspaces rename --from test-utils test_utils
           cargo workspaces rename --from text-edit text_edit
           cargo workspaces rename ra_ap_%n
+          # Remove library crates from the workspaces so we don't auto-publish them as well
+          sed -i 's/ "lib\/\*",//' ./Cargo.toml
           find crates/rust-analyzer -type f -name '*.rs' -exec sed -i 's/rust_analyzer/ra_ap_rust_analyzer/g' {} +
           cargo workspaces publish --yes --force '*' --exact --no-git-commit --allow-dirty --skip-published custom 0.0.$PATCH
diff --git a/src/tools/rust-analyzer/.github/workflows/release.yaml b/src/tools/rust-analyzer/.github/workflows/release.yaml
index 422fe29f9d5c..b070dd3406f2 100644
--- a/src/tools/rust-analyzer/.github/workflows/release.yaml
+++ b/src/tools/rust-analyzer/.github/workflows/release.yaml
@@ -257,8 +257,7 @@ jobs:
       - name: Publish Extension (OpenVSX, release)
         if: github.ref == 'refs/heads/release' && (github.repository == 'rust-analyzer/rust-analyzer' || github.repository == 'rust-lang/rust-analyzer')
         working-directory: ./editors/code
-        # token from https://dev.azure.com/rust-analyzer/
-        run: npx ovsx publish --pat ${{ secrets.OPENVSX_TOKEN }} --packagePath ../../dist/rust-analyzer-*.vsix || true
+        run: npx ovsx publish --pat ${{ secrets.OPENVSX_TOKEN }} --packagePath ../../dist/rust-analyzer-*.vsix
         timeout-minutes: 2
 
       - name: Publish Extension (Code Marketplace, nightly)
@@ -269,5 +268,5 @@ jobs:
       - name: Publish Extension (OpenVSX, nightly)
         if: github.ref != 'refs/heads/release' && (github.repository == 'rust-analyzer/rust-analyzer' || github.repository == 'rust-lang/rust-analyzer')
         working-directory: ./editors/code
-        run: npx ovsx publish --pat ${{ secrets.OPENVSX_TOKEN }} --packagePath ../../dist/rust-analyzer-*.vsix || true
+        run: npx ovsx publish --pat ${{ secrets.OPENVSX_TOKEN }} --packagePath ../../dist/rust-analyzer-*.vsix
         timeout-minutes: 2
diff --git a/src/tools/rust-analyzer/Cargo.lock b/src/tools/rust-analyzer/Cargo.lock
index 0ddea2f728d7..8931c17bbdc1 100644
--- a/src/tools/rust-analyzer/Cargo.lock
+++ b/src/tools/rust-analyzer/Cargo.lock
@@ -872,9 +872,9 @@ dependencies = [
 
 [[package]]
 name = "lsp-types"
-version = "0.93.1"
+version = "0.93.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a3bcfee315dde785ba887edb540b08765fd7df75a7d948844be6bf5712246734"
+checksum = "9be6e9c7e2d18f651974370d7aff703f9513e0df6e464fd795660edc77e6ca51"
 dependencies = [
  "bitflags",
  "serde",
diff --git a/src/tools/rust-analyzer/crates/flycheck/src/lib.rs b/src/tools/rust-analyzer/crates/flycheck/src/lib.rs
index e8c63d410aa7..8a91d6066614 100644
--- a/src/tools/rust-analyzer/crates/flycheck/src/lib.rs
+++ b/src/tools/rust-analyzer/crates/flycheck/src/lib.rs
@@ -21,6 +21,20 @@ pub use cargo_metadata::diagnostic::{
     DiagnosticSpanMacroExpansion,
 };
 
+#[derive(Copy, Clone, Debug, Default, PartialEq, Eq)]
+pub enum InvocationStrategy {
+    Once,
+    #[default]
+    PerWorkspace,
+}
+
+#[derive(Clone, Debug, Default, PartialEq, Eq)]
+pub enum InvocationLocation {
+    Root(AbsPathBuf),
+    #[default]
+    Workspace,
+}
+
 #[derive(Clone, Debug, PartialEq, Eq)]
 pub enum FlycheckConfig {
     CargoCommand {
@@ -37,6 +51,8 @@ pub enum FlycheckConfig {
         command: String,
         args: Vec<String>,
         extra_env: FxHashMap<String, String>,
+        invocation_strategy: InvocationStrategy,
+        invocation_location: InvocationLocation,
     },
 }
 
@@ -136,11 +152,15 @@ enum Restart {
     No,
 }
 
+/// A [`FlycheckActor`] is a single check instance of a workspace.
 struct FlycheckActor {
+    /// The workspace id of this flycheck instance.
     id: usize,
     sender: Box<dyn Fn(Message) + Send>,
     config: FlycheckConfig,
-    workspace_root: AbsPathBuf,
+    /// Either the workspace root of the workspace we are flychecking,
+    /// or the project root of the project.
+    root: AbsPathBuf,
     /// CargoHandle exists to wrap around the communication needed to be able to
     /// run `cargo check` without blocking. Currently the Rust standard library
     /// doesn't provide a way to read sub-process output without blocking, so we
@@ -162,11 +182,13 @@ impl FlycheckActor {
         workspace_root: AbsPathBuf,
     ) -> FlycheckActor {
         tracing::info!(%id, ?workspace_root, "Spawning flycheck");
-        FlycheckActor { id, sender, config, workspace_root, cargo_handle: None }
+        FlycheckActor { id, sender, config, root: workspace_root, cargo_handle: None }
     }
-    fn progress(&self, progress: Progress) {
+
+    fn report_progress(&self, progress: Progress) {
         self.send(Message::Progress { id: self.id, progress });
     }
+
     fn next_event(&self, inbox: &Receiver<Restart>) -> Option<Event> {
         let check_chan = self.cargo_handle.as_ref().map(|cargo| &cargo.receiver);
         if let Ok(msg) = inbox.try_recv() {
@@ -178,6 +200,7 @@ impl FlycheckActor {
             recv(check_chan.unwrap_or(&never())) -> msg => Some(Event::CheckEvent(msg.ok())),
         }
     }
+
     fn run(mut self, inbox: Receiver<Restart>) {
         'event: while let Some(event) = self.next_event(&inbox) {
             match event {
@@ -203,10 +226,10 @@ impl FlycheckActor {
                                 "did  restart flycheck"
                             );
                             self.cargo_handle = Some(cargo_handle);
-                            self.progress(Progress::DidStart);
+                            self.report_progress(Progress::DidStart);
                         }
                         Err(error) => {
-                            self.progress(Progress::DidFailToRestart(format!(
+                            self.report_progress(Progress::DidFailToRestart(format!(
                                 "Failed to run the following command: {:?} error={}",
                                 self.check_command(),
                                 error
@@ -226,17 +249,17 @@ impl FlycheckActor {
                             self.check_command()
                         );
                     }
-                    self.progress(Progress::DidFinish(res));
+                    self.report_progress(Progress::DidFinish(res));
                 }
                 Event::CheckEvent(Some(message)) => match message {
                     CargoMessage::CompilerArtifact(msg) => {
-                        self.progress(Progress::DidCheckCrate(msg.target.name));
+                        self.report_progress(Progress::DidCheckCrate(msg.target.name));
                     }
 
                     CargoMessage::Diagnostic(msg) => {
                         self.send(Message::AddDiagnostic {
                             id: self.id,
-                            workspace_root: self.workspace_root.clone(),
+                            workspace_root: self.root.clone(),
                             diagnostic: msg,
                         });
                     }
@@ -254,12 +277,12 @@ impl FlycheckActor {
                 "did  cancel flycheck"
             );
             cargo_handle.cancel();
-            self.progress(Progress::DidCancel);
+            self.report_progress(Progress::DidCancel);
         }
     }
 
     fn check_command(&self) -> Command {
-        let mut cmd = match &self.config {
+        let (mut cmd, args) = match &self.config {
             FlycheckConfig::CargoCommand {
                 command,
                 target_triple,
@@ -272,9 +295,9 @@ impl FlycheckActor {
             } => {
                 let mut cmd = Command::new(toolchain::cargo());
                 cmd.arg(command);
-                cmd.current_dir(&self.workspace_root);
+                cmd.current_dir(&self.root);
                 cmd.args(&["--workspace", "--message-format=json", "--manifest-path"])
-                    .arg(self.workspace_root.join("Cargo.toml").as_os_str());
+                    .arg(self.root.join("Cargo.toml").as_os_str());
 
                 if let Some(target) = target_triple {
                     cmd.args(&["--target", target.as_str()]);
@@ -293,18 +316,41 @@ impl FlycheckActor {
                         cmd.arg(features.join(" "));
                     }
                 }
-                cmd.args(extra_args);
                 cmd.envs(extra_env);
-                cmd
+                (cmd, extra_args)
             }
-            FlycheckConfig::CustomCommand { command, args, extra_env } => {
+            FlycheckConfig::CustomCommand {
+                command,
+                args,
+                extra_env,
+                invocation_strategy,
+                invocation_location,
+            } => {
                 let mut cmd = Command::new(command);
-                cmd.args(args);
                 cmd.envs(extra_env);
-                cmd
+
+                match invocation_location {
+                    InvocationLocation::Workspace => {
+                        match invocation_strategy {
+                            InvocationStrategy::Once => {
+                                cmd.current_dir(&self.root);
+                            }
+                            InvocationStrategy::PerWorkspace => {
+                                // FIXME: cmd.current_dir(&affected_workspace);
+                                cmd.current_dir(&self.root);
+                            }
+                        }
+                    }
+                    InvocationLocation::Root(root) => {
+                        cmd.current_dir(root);
+                    }
+                }
+
+                (cmd, args)
             }
         };
-        cmd.current_dir(&self.workspace_root);
+
+        cmd.args(args);
         cmd
     }
 
diff --git a/src/tools/rust-analyzer/crates/hir-def/src/item_tree/lower.rs b/src/tools/rust-analyzer/crates/hir-def/src/item_tree/lower.rs
index 077a1b619dd5..79249757d9e9 100644
--- a/src/tools/rust-analyzer/crates/hir-def/src/item_tree/lower.rs
+++ b/src/tools/rust-analyzer/crates/hir-def/src/item_tree/lower.rs
@@ -662,8 +662,12 @@ fn desugar_future_path(orig: TypeRef) -> Path {
     let mut generic_args: Vec<_> =
         std::iter::repeat(None).take(path.segments().len() - 1).collect();
     let mut last = GenericArgs::empty();
-    let binding =
-        AssociatedTypeBinding { name: name![Output], type_ref: Some(orig), bounds: Vec::new() };
+    let binding = AssociatedTypeBinding {
+        name: name![Output],
+        args: None,
+        type_ref: Some(orig),
+        bounds: Vec::new(),
+    };
     last.bindings.push(binding);
     generic_args.push(Some(Interned::new(last)));
 
diff --git a/src/tools/rust-analyzer/crates/hir-def/src/macro_expansion_tests/builtin_derive_macro.rs b/src/tools/rust-analyzer/crates/hir-def/src/macro_expansion_tests/builtin_derive_macro.rs
index 6819e9114a02..fafcde25ae70 100644
--- a/src/tools/rust-analyzer/crates/hir-def/src/macro_expansion_tests/builtin_derive_macro.rs
+++ b/src/tools/rust-analyzer/crates/hir-def/src/macro_expansion_tests/builtin_derive_macro.rs
@@ -12,11 +12,11 @@ fn test_copy_expand_simple() {
 #[derive(Copy)]
 struct Foo;
 "#,
-        expect![[r##"
+        expect![[r#"
 #[derive(Copy)]
 struct Foo;
 
-impl < > core::marker::Copy for Foo< > {}"##]],
+impl < > core::marker::Copy for Foo< > {}"#]],
     );
 }
 
@@ -33,7 +33,7 @@ macro Copy {}
 #[derive(Copy)]
 struct Foo;
 "#,
-        expect![[r##"
+        expect![[r#"
 #[rustc_builtin_macro]
 macro derive {}
 #[rustc_builtin_macro]
@@ -41,7 +41,7 @@ macro Copy {}
 #[derive(Copy)]
 struct Foo;
 
-impl < > crate ::marker::Copy for Foo< > {}"##]],
+impl < > crate ::marker::Copy for Foo< > {}"#]],
     );
 }
 
@@ -53,11 +53,11 @@ fn test_copy_expand_with_type_params() {
 #[derive(Copy)]
 struct Foo<A, B>;
 "#,
-        expect![[r##"
+        expect![[r#"
 #[derive(Copy)]
 struct Foo<A, B>;
 
-impl <T0: core::marker::Copy, T1: core::marker::Copy> core::marker::Copy for Foo<T0, T1> {}"##]],
+impl <T0: core::marker::Copy, T1: core::marker::Copy, > core::marker::Copy for Foo<T0, T1, > {}"#]],
     );
 }
 
@@ -70,11 +70,11 @@ fn test_copy_expand_with_lifetimes() {
 #[derive(Copy)]
 struct Foo<A, B, 'a, 'b>;
 "#,
-        expect![[r##"
+        expect![[r#"
 #[derive(Copy)]
 struct Foo<A, B, 'a, 'b>;
 
-impl <T0: core::marker::Copy, T1: core::marker::Copy> core::marker::Copy for Foo<T0, T1> {}"##]],
+impl <T0: core::marker::Copy, T1: core::marker::Copy, > core::marker::Copy for Foo<T0, T1, > {}"#]],
     );
 }
 
@@ -86,10 +86,26 @@ fn test_clone_expand() {
 #[derive(Clone)]
 struct Foo<A, B>;
 "#,
-        expect![[r##"
+        expect![[r#"
 #[derive(Clone)]
 struct Foo<A, B>;
 
-impl <T0: core::clone::Clone, T1: core::clone::Clone> core::clone::Clone for Foo<T0, T1> {}"##]],
+impl <T0: core::clone::Clone, T1: core::clone::Clone, > core::clone::Clone for Foo<T0, T1, > {}"#]],
+    );
+}
+
+#[test]
+fn test_clone_expand_with_const_generics() {
+    check(
+        r#"
+//- minicore: derive, clone
+#[derive(Clone)]
+struct Foo<const X: usize, T>(u32);
+"#,
+        expect![[r#"
+#[derive(Clone)]
+struct Foo<const X: usize, T>(u32);
+
+impl <const T0: usize, T1: core::clone::Clone, > core::clone::Clone for Foo<T0, T1, > {}"#]],
     );
 }
diff --git a/src/tools/rust-analyzer/crates/hir-def/src/path.rs b/src/tools/rust-analyzer/crates/hir-def/src/path.rs
index 2f13a9fbf0e4..592223f7d85f 100644
--- a/src/tools/rust-analyzer/crates/hir-def/src/path.rs
+++ b/src/tools/rust-analyzer/crates/hir-def/src/path.rs
@@ -68,6 +68,9 @@ pub struct GenericArgs {
 pub struct AssociatedTypeBinding {
     /// The name of the associated type.
     pub name: Name,
+    /// The generic arguments to the associated type. e.g. For `Trait<Assoc<'a, T> = &'a T>`, this
+    /// would be `['a, T]`.
+    pub args: Option<Interned<GenericArgs>>,
     /// The type bound to this associated type (in `Item = T`, this would be the
     /// `T`). This can be `None` if there are bounds instead.
     pub type_ref: Option<TypeRef>,
diff --git a/src/tools/rust-analyzer/crates/hir-def/src/path/lower.rs b/src/tools/rust-analyzer/crates/hir-def/src/path/lower.rs
index 0428f1a398b1..cfa3a6baaf8b 100644
--- a/src/tools/rust-analyzer/crates/hir-def/src/path/lower.rs
+++ b/src/tools/rust-analyzer/crates/hir-def/src/path/lower.rs
@@ -163,6 +163,10 @@ pub(super) fn lower_generic_args(
             ast::GenericArg::AssocTypeArg(assoc_type_arg) => {
                 if let Some(name_ref) = assoc_type_arg.name_ref() {
                     let name = name_ref.as_name();
+                    let args = assoc_type_arg
+                        .generic_arg_list()
+                        .and_then(|args| lower_generic_args(lower_ctx, args))
+                        .map(Interned::new);
                     let type_ref = assoc_type_arg.ty().map(|it| TypeRef::from_ast(lower_ctx, it));
                     let bounds = if let Some(l) = assoc_type_arg.type_bound_list() {
                         l.bounds()
@@ -171,7 +175,7 @@ pub(super) fn lower_generic_args(
                     } else {
                         Vec::new()
                     };
-                    bindings.push(AssociatedTypeBinding { name, type_ref, bounds });
+                    bindings.push(AssociatedTypeBinding { name, args, type_ref, bounds });
                 }
             }
             ast::GenericArg::LifetimeArg(lifetime_arg) => {
@@ -214,6 +218,7 @@ fn lower_generic_args_from_fn_path(
         let type_ref = TypeRef::from_ast_opt(ctx, ret_type.ty());
         bindings.push(AssociatedTypeBinding {
             name: name![Output],
+            args: None,
             type_ref: Some(type_ref),
             bounds: Vec::new(),
         });
@@ -222,6 +227,7 @@ fn lower_generic_args_from_fn_path(
         let type_ref = TypeRef::Tuple(Vec::new());
         bindings.push(AssociatedTypeBinding {
             name: name![Output],
+            args: None,
             type_ref: Some(type_ref),
             bounds: Vec::new(),
         });
diff --git a/src/tools/rust-analyzer/crates/hir-def/src/pretty.rs b/src/tools/rust-analyzer/crates/hir-def/src/pretty.rs
index 6636c8a23ca5..933970d10e47 100644
--- a/src/tools/rust-analyzer/crates/hir-def/src/pretty.rs
+++ b/src/tools/rust-analyzer/crates/hir-def/src/pretty.rs
@@ -143,9 +143,12 @@ pub(crate) fn print_type_ref(type_ref: &TypeRef, buf: &mut dyn Write) -> fmt::Re
             print_type_ref(elem, buf)?;
             write!(buf, "]")?;
         }
-        TypeRef::Fn(args_and_ret, varargs) => {
+        TypeRef::Fn(args_and_ret, varargs, is_unsafe) => {
             let ((_, return_type), args) =
                 args_and_ret.split_last().expect("TypeRef::Fn is missing return type");
+            if *is_unsafe {
+                write!(buf, "unsafe ")?;
+            }
             write!(buf, "fn(")?;
             for (i, (_, typeref)) in args.iter().enumerate() {
                 if i != 0 {
diff --git a/src/tools/rust-analyzer/crates/hir-def/src/type_ref.rs b/src/tools/rust-analyzer/crates/hir-def/src/type_ref.rs
index 5b4c71be7fb8..f8bb78ddcfe0 100644
--- a/src/tools/rust-analyzer/crates/hir-def/src/type_ref.rs
+++ b/src/tools/rust-analyzer/crates/hir-def/src/type_ref.rs
@@ -119,7 +119,7 @@ pub enum TypeRef {
     Array(Box<TypeRef>, ConstScalarOrPath),
     Slice(Box<TypeRef>),
     /// A fn pointer. Last element of the vector is the return type.
-    Fn(Vec<(Option<Name>, TypeRef)>, bool /*varargs*/),
+    Fn(Vec<(Option<Name>, TypeRef)>, bool /*varargs*/, bool /*is_unsafe*/),
     ImplTrait(Vec<Interned<TypeBound>>),
     DynTrait(Vec<Interned<TypeBound>>),
     Macro(AstId<ast::MacroCall>),
@@ -229,7 +229,7 @@ impl TypeRef {
                     Vec::new()
                 };
                 params.push((None, ret_ty));
-                TypeRef::Fn(params, is_varargs)
+                TypeRef::Fn(params, is_varargs, inner.unsafe_token().is_some())
             }
             // for types are close enough for our purposes to the inner type for now...
             ast::Type::ForType(inner) => TypeRef::from_ast_opt(ctx, inner.ty()),
@@ -263,7 +263,7 @@ impl TypeRef {
         fn go(type_ref: &TypeRef, f: &mut impl FnMut(&TypeRef)) {
             f(type_ref);
             match type_ref {
-                TypeRef::Fn(params, _) => {
+                TypeRef::Fn(params, _, _) => {
                     params.iter().for_each(|(_, param_type)| go(param_type, f))
                 }
                 TypeRef::Tuple(types) => types.iter().for_each(|t| go(t, f)),
diff --git a/src/tools/rust-analyzer/crates/hir-expand/src/builtin_derive_macro.rs b/src/tools/rust-analyzer/crates/hir-expand/src/builtin_derive_macro.rs
index 79989bc2e38b..8966047c9b25 100644
--- a/src/tools/rust-analyzer/crates/hir-expand/src/builtin_derive_macro.rs
+++ b/src/tools/rust-analyzer/crates/hir-expand/src/builtin_derive_macro.rs
@@ -60,7 +60,8 @@ pub fn find_builtin_derive(ident: &name::Name) -> Option<BuiltinDeriveExpander>
 
 struct BasicAdtInfo {
     name: tt::Ident,
-    type_or_const_params: usize,
+    /// `Some(ty)` if it's a const param of type `ty`, `None` if it's a type param.
+    param_types: Vec<Option<tt::Subtree>>,
 }
 
 fn parse_adt(tt: &tt::Subtree) -> Result<BasicAdtInfo, ExpandError> {
@@ -92,50 +93,22 @@ fn parse_adt(tt: &tt::Subtree) -> Result<BasicAdtInfo, ExpandError> {
     let name_token_id =
         token_map.token_by_range(name.syntax().text_range()).unwrap_or_else(TokenId::unspecified);
     let name_token = tt::Ident { id: name_token_id, text: name.text().into() };
-    let type_or_const_params =
-        params.map_or(0, |type_param_list| type_param_list.type_or_const_params().count());
-    Ok(BasicAdtInfo { name: name_token, type_or_const_params })
-}
-
-fn make_type_args(n: usize, bound: Vec<tt::TokenTree>) -> Vec<tt::TokenTree> {
-    let mut result = Vec::<tt::TokenTree>::with_capacity(n * 2);
-    result.push(
-        tt::Leaf::Punct(tt::Punct {
-            char: '<',
-            spacing: tt::Spacing::Alone,
-            id: tt::TokenId::unspecified(),
+    let param_types = params
+        .into_iter()
+        .flat_map(|param_list| param_list.type_or_const_params())
+        .map(|param| {
+            if let ast::TypeOrConstParam::Const(param) = param {
+                let ty = param
+                    .ty()
+                    .map(|ty| mbe::syntax_node_to_token_tree(ty.syntax()).0)
+                    .unwrap_or_default();
+                Some(ty)
+            } else {
+                None
+            }
         })
-        .into(),
-    );
-    for i in 0..n {
-        if i > 0 {
-            result.push(
-                tt::Leaf::Punct(tt::Punct {
-                    char: ',',
-                    spacing: tt::Spacing::Alone,
-                    id: tt::TokenId::unspecified(),
-                })
-                .into(),
-            );
-        }
-        result.push(
-            tt::Leaf::Ident(tt::Ident {
-                id: tt::TokenId::unspecified(),
-                text: format!("T{}", i).into(),
-            })
-            .into(),
-        );
-        result.extend(bound.iter().cloned());
-    }
-    result.push(
-        tt::Leaf::Punct(tt::Punct {
-            char: '>',
-            spacing: tt::Spacing::Alone,
-            id: tt::TokenId::unspecified(),
-        })
-        .into(),
-    );
-    result
+        .collect();
+    Ok(BasicAdtInfo { name: name_token, param_types })
 }
 
 fn expand_simple_derive(tt: &tt::Subtree, trait_path: tt::Subtree) -> ExpandResult<tt::Subtree> {
@@ -143,14 +116,27 @@ fn expand_simple_derive(tt: &tt::Subtree, trait_path: tt::Subtree) -> ExpandResu
         Ok(info) => info,
         Err(e) => return ExpandResult::only_err(e),
     };
+    let (params, args): (Vec<_>, Vec<_>) = info
+        .param_types
+        .into_iter()
+        .enumerate()
+        .map(|(idx, param_ty)| {
+            let ident = tt::Leaf::Ident(tt::Ident {
+                id: tt::TokenId::unspecified(),
+                text: format!("T{idx}").into(),
+            });
+            let ident_ = ident.clone();
+            if let Some(ty) = param_ty {
+                (quote! { const #ident : #ty , }, quote! { #ident_ , })
+            } else {
+                let bound = trait_path.clone();
+                (quote! { #ident : #bound , }, quote! { #ident_ , })
+            }
+        })
+        .unzip();
     let name = info.name;
-    let trait_path_clone = trait_path.token_trees.clone();
-    let bound = (quote! { : ##trait_path_clone }).token_trees;
-    let type_params = make_type_args(info.type_or_const_params, bound);
-    let type_args = make_type_args(info.type_or_const_params, Vec::new());
-    let trait_path = trait_path.token_trees;
     let expanded = quote! {
-        impl ##type_params ##trait_path for #name ##type_args {}
+        impl < ##params > #trait_path for #name < ##args > {}
     };
     ExpandResult::ok(expanded)
 }
diff --git a/src/tools/rust-analyzer/crates/hir-expand/src/mod_path.rs b/src/tools/rust-analyzer/crates/hir-expand/src/mod_path.rs
index 68413df420c7..d7586d129b76 100644
--- a/src/tools/rust-analyzer/crates/hir-expand/src/mod_path.rs
+++ b/src/tools/rust-analyzer/crates/hir-expand/src/mod_path.rs
@@ -259,7 +259,6 @@ macro_rules! __known_path {
     (core::future::Future) => {};
     (core::future::IntoFuture) => {};
     (core::ops::Try) => {};
-    (core::ops::FromResidual) => {};
     ($path:path) => {
         compile_error!("Please register your known path in the path module")
     };
diff --git a/src/tools/rust-analyzer/crates/hir-expand/src/name.rs b/src/tools/rust-analyzer/crates/hir-expand/src/name.rs
index 8a735b965ab8..2679a1c36026 100644
--- a/src/tools/rust-analyzer/crates/hir-expand/src/name.rs
+++ b/src/tools/rust-analyzer/crates/hir-expand/src/name.rs
@@ -279,8 +279,6 @@ pub mod known {
         RangeToInclusive,
         RangeTo,
         Range,
-        Residual,
-        FromResidual,
         Neg,
         Not,
         None,
diff --git a/src/tools/rust-analyzer/crates/hir-ty/src/chalk_ext.rs b/src/tools/rust-analyzer/crates/hir-ty/src/chalk_ext.rs
index e2099d7e5092..996b42f5bd83 100644
--- a/src/tools/rust-analyzer/crates/hir-ty/src/chalk_ext.rs
+++ b/src/tools/rust-analyzer/crates/hir-ty/src/chalk_ext.rs
@@ -11,9 +11,9 @@ use syntax::SmolStr;
 
 use crate::{
     db::HirDatabase, from_assoc_type_id, from_chalk_trait_id, from_foreign_def_id,
-    from_placeholder_idx, to_chalk_trait_id, AdtId, AliasEq, AliasTy, Binders, CallableDefId,
-    CallableSig, FnPointer, ImplTraitId, Interner, Lifetime, ProjectionTy, QuantifiedWhereClause,
-    Substitution, TraitRef, Ty, TyBuilder, TyKind, WhereClause,
+    from_placeholder_idx, to_chalk_trait_id, utils::generics, AdtId, AliasEq, AliasTy, Binders,
+    CallableDefId, CallableSig, FnPointer, ImplTraitId, Interner, Lifetime, ProjectionTy,
+    QuantifiedWhereClause, Substitution, TraitRef, Ty, TyBuilder, TyKind, WhereClause,
 };
 
 pub trait TyExt {
@@ -338,10 +338,13 @@ pub trait ProjectionTyExt {
 
 impl ProjectionTyExt for ProjectionTy {
     fn trait_ref(&self, db: &dyn HirDatabase) -> TraitRef {
-        TraitRef {
-            trait_id: to_chalk_trait_id(self.trait_(db)),
-            substitution: self.substitution.clone(),
-        }
+        // FIXME: something like `Split` trait from chalk-solve might be nice.
+        let generics = generics(db.upcast(), from_assoc_type_id(self.associated_ty_id).into());
+        let substitution = Substitution::from_iter(
+            Interner,
+            self.substitution.iter(Interner).skip(generics.len_self()),
+        );
+        TraitRef { trait_id: to_chalk_trait_id(self.trait_(db)), substitution }
     }
 
     fn trait_(&self, db: &dyn HirDatabase) -> TraitId {
diff --git a/src/tools/rust-analyzer/crates/hir-ty/src/display.rs b/src/tools/rust-analyzer/crates/hir-ty/src/display.rs
index 0221f922feb2..a22a4b170f61 100644
--- a/src/tools/rust-analyzer/crates/hir-ty/src/display.rs
+++ b/src/tools/rust-analyzer/crates/hir-ty/src/display.rs
@@ -289,16 +289,18 @@ impl HirDisplay for ProjectionTy {
             return write!(f, "{}", TYPE_HINT_TRUNCATION);
         }
 
-        let trait_ = f.db.trait_data(self.trait_(f.db));
+        let trait_ref = self.trait_ref(f.db);
         write!(f, "<")?;
-        self.self_type_parameter(f.db).hir_fmt(f)?;
-        write!(f, " as {}", trait_.name)?;
-        if self.substitution.len(Interner) > 1 {
+        fmt_trait_ref(&trait_ref, f, true)?;
+        write!(f, ">::{}", f.db.type_alias_data(from_assoc_type_id(self.associated_ty_id)).name)?;
+        let proj_params_count =
+            self.substitution.len(Interner) - trait_ref.substitution.len(Interner);
+        let proj_params = &self.substitution.as_slice(Interner)[..proj_params_count];
+        if !proj_params.is_empty() {
             write!(f, "<")?;
-            f.write_joined(&self.substitution.as_slice(Interner)[1..], ", ")?;
+            f.write_joined(proj_params, ", ")?;
             write!(f, ">")?;
         }
-        write!(f, ">::{}", f.db.type_alias_data(from_assoc_type_id(self.associated_ty_id)).name)?;
         Ok(())
     }
 }
@@ -641,9 +643,12 @@ impl HirDisplay for Ty {
                 // Use placeholder associated types when the target is test (https://rust-lang.github.io/chalk/book/clauses/type_equality.html#placeholder-associated-types)
                 if f.display_target.is_test() {
                     write!(f, "{}::{}", trait_.name, type_alias_data.name)?;
+                    // Note that the generic args for the associated type come before those for the
+                    // trait (including the self type).
+                    // FIXME: reconsider the generic args order upon formatting?
                     if parameters.len(Interner) > 0 {
                         write!(f, "<")?;
-                        f.write_joined(&*parameters.as_slice(Interner), ", ")?;
+                        f.write_joined(parameters.as_slice(Interner), ", ")?;
                         write!(f, ">")?;
                     }
                 } else {
@@ -972,9 +977,20 @@ fn write_bounds_like_dyn_trait(
                     angle_open = true;
                 }
                 if let AliasTy::Projection(proj) = alias {
-                    let type_alias =
-                        f.db.type_alias_data(from_assoc_type_id(proj.associated_ty_id));
-                    write!(f, "{} = ", type_alias.name)?;
+                    let assoc_ty_id = from_assoc_type_id(proj.associated_ty_id);
+                    let type_alias = f.db.type_alias_data(assoc_ty_id);
+                    write!(f, "{}", type_alias.name)?;
+
+                    let proj_arg_count = generics(f.db.upcast(), assoc_ty_id.into()).len_self();
+                    if proj_arg_count > 0 {
+                        write!(f, "<")?;
+                        f.write_joined(
+                            &proj.substitution.as_slice(Interner)[..proj_arg_count],
+                            ", ",
+                        )?;
+                        write!(f, ">")?;
+                    }
+                    write!(f, " = ")?;
                 }
                 ty.hir_fmt(f)?;
             }
@@ -1171,8 +1187,11 @@ impl HirDisplay for TypeRef {
                 inner.hir_fmt(f)?;
                 write!(f, "]")?;
             }
-            TypeRef::Fn(parameters, is_varargs) => {
+            &TypeRef::Fn(ref parameters, is_varargs, is_unsafe) => {
                 // FIXME: Function pointer qualifiers.
+                if is_unsafe {
+                    write!(f, "unsafe ")?;
+                }
                 write!(f, "fn(")?;
                 if let Some(((_, return_type), function_parameters)) = parameters.split_last() {
                     for index in 0..function_parameters.len() {
@@ -1187,7 +1206,7 @@ impl HirDisplay for TypeRef {
                             write!(f, ", ")?;
                         }
                     }
-                    if *is_varargs {
+                    if is_varargs {
                         write!(f, "{}...", if parameters.len() == 1 { "" } else { ", " })?;
                     }
                     write!(f, ")")?;
diff --git a/src/tools/rust-analyzer/crates/hir-ty/src/infer.rs b/src/tools/rust-analyzer/crates/hir-ty/src/infer.rs
index 6a5c4966f7ba..0b3c23f5747a 100644
--- a/src/tools/rust-analyzer/crates/hir-ty/src/infer.rs
+++ b/src/tools/rust-analyzer/crates/hir-ty/src/infer.rs
@@ -190,9 +190,7 @@ pub(crate) type InferResult<T> = Result<InferOk<T>, TypeError>;
 pub enum InferenceDiagnostic {
     NoSuchField { expr: ExprId },
     BreakOutsideOfLoop { expr: ExprId, is_break: bool },
-    IncorrectTryTarget { expr: ExprId },
     MismatchedArgCount { call_expr: ExprId, expected: usize, found: usize },
-    DoesNotImplement { expr: ExprId, trait_: TraitId, ty: Ty },
 }
 
 /// A mismatch between an expected and an inferred type.
@@ -907,6 +905,17 @@ impl<'a> InferenceContext<'a> {
         self.db.trait_data(trait_).associated_type_by_name(&name![Item])
     }
 
+    fn resolve_ops_try_ok(&self) -> Option<TypeAliasId> {
+        // FIXME resolve via lang_item once try v2 is stable
+        let path = path![core::ops::Try];
+        let trait_ = self.resolver.resolve_known_trait(self.db.upcast(), &path)?;
+        let trait_data = self.db.trait_data(trait_);
+        trait_data
+            // FIXME remove once try v2 is stable
+            .associated_type_by_name(&name![Ok])
+            .or_else(|| trait_data.associated_type_by_name(&name![Output]))
+    }
+
     fn resolve_ops_neg_output(&self) -> Option<TypeAliasId> {
         let trait_ = self.resolve_lang_item(name![neg])?.as_trait()?;
         self.db.trait_data(trait_).associated_type_by_name(&name![Output])
@@ -1011,7 +1020,7 @@ impl Expectation {
     /// The primary use case is where the expected type is a fat pointer,
     /// like `&[isize]`. For example, consider the following statement:
     ///
-    ///    let x: &[isize] = &[1, 2, 3];
+    ///     let x: &[isize] = &[1, 2, 3];
     ///
     /// In this case, the expected type for the `&[1, 2, 3]` expression is
     /// `&[isize]`. If however we were to say that `[1, 2, 3]` has the
diff --git a/src/tools/rust-analyzer/crates/hir-ty/src/infer/expr.rs b/src/tools/rust-analyzer/crates/hir-ty/src/infer/expr.rs
index 59ab50d0717b..b1f4de826077 100644
--- a/src/tools/rust-analyzer/crates/hir-ty/src/infer/expr.rs
+++ b/src/tools/rust-analyzer/crates/hir-ty/src/infer/expr.rs
@@ -19,24 +19,24 @@ use hir_def::{
     resolver::resolver_for_expr,
     ConstParamId, FieldId, ItemContainerId, Lookup,
 };
-use hir_expand::{name, name::Name};
+use hir_expand::name::Name;
 use stdx::always;
 use syntax::ast::RangeOp;
 
 use crate::{
     autoderef::{self, Autoderef},
     consteval,
-    infer::{coerce::CoerceMany, find_continuable, path, BreakableKind},
+    infer::{coerce::CoerceMany, find_continuable, BreakableKind},
     lower::{
         const_or_path_to_chalk, generic_arg_to_chalk, lower_to_chalk_mutability, ParamLoweringMode,
     },
     mapping::{from_chalk, ToChalk},
     method_resolution::{self, lang_names_for_bin_op, VisibleFromModule},
     primitive::{self, UintTy},
-    static_lifetime, to_assoc_type_id, to_chalk_trait_id,
+    static_lifetime, to_chalk_trait_id,
     utils::{generics, Generics},
-    AdtId, AliasEq, AliasTy, Binders, CallableDefId, FnPointer, FnSig, FnSubst, Interner,
-    ProjectionTy, Rawness, Scalar, Substitution, TraitRef, Ty, TyBuilder, TyExt, TyKind,
+    AdtId, Binders, CallableDefId, FnPointer, FnSig, FnSubst, Interner, Rawness, Scalar,
+    Substitution, TraitRef, Ty, TyBuilder, TyExt, TyKind,
 };
 
 use super::{
@@ -85,6 +85,7 @@ impl<'a> InferenceContext<'a> {
         let ty = match &self.body[tgt_expr] {
             Expr::Missing => self.err_ty(),
             &Expr::If { condition, then_branch, else_branch } => {
+                let expected = &expected.adjust_for_branches(&mut self.table);
                 self.infer_expr(
                     condition,
                     &Expectation::has_type(TyKind::Scalar(Scalar::Bool).intern(Interner)),
@@ -564,29 +565,9 @@ impl<'a> InferenceContext<'a> {
                 let inner_ty = self.infer_expr_inner(*expr, &Expectation::none());
                 self.resolve_associated_type(inner_ty, self.resolve_future_future_output())
             }
-            &Expr::Try { expr } => {
-                let inner_ty = self.infer_expr_inner(expr, &Expectation::none());
-                match self.resolve_try_impl_for(inner_ty.clone()) {
-                    Some((_, Some((output, residual)))) => {
-                        if let Some((_trait, false)) =
-                            self.implements_from_residual(self.return_ty.clone(), residual)
-                        {
-                            self.push_diagnostic(InferenceDiagnostic::IncorrectTryTarget {
-                                expr: tgt_expr,
-                            });
-                        }
-                        output
-                    }
-                    Some((trait_, None)) => {
-                        self.push_diagnostic(InferenceDiagnostic::DoesNotImplement {
-                            expr,
-                            trait_,
-                            ty: inner_ty,
-                        });
-                        self.err_ty()
-                    }
-                    None => self.err_ty(),
-                }
+            Expr::Try { expr } => {
+                let inner_ty = self.infer_expr_inner(*expr, &Expectation::none());
+                self.resolve_associated_type(inner_ty, self.resolve_ops_try_ok())
             }
             Expr::Cast { expr, type_ref } => {
                 // FIXME: propagate the "castable to" expectation (and find a test case that shows this is necessary)
@@ -1550,67 +1531,4 @@ impl<'a> InferenceContext<'a> {
         let ctx = self.breakables.pop().expect("breakable stack broken");
         (ctx.may_break.then(|| ctx.coerce.complete()), res)
     }
-
-    /// Check whether `ty` implements `FromResidual<r>`
-    fn implements_from_residual(&mut self, ty: Ty, r: Ty) -> Option<(hir_def::TraitId, bool)> {
-        let from_residual_trait = self
-            .resolver
-            .resolve_known_trait(self.db.upcast(), &(super::path![core::ops::FromResidual]))?;
-        let r = GenericArgData::Ty(r).intern(Interner);
-        let b = TyBuilder::trait_ref(self.db, from_residual_trait);
-        if b.remaining() != 2 {
-            return Some((from_residual_trait, false));
-        }
-        let trait_ref = b.push(ty).push(r).build();
-        Some((from_residual_trait, self.table.try_obligation(trait_ref.cast(Interner)).is_some()))
-    }
-
-    fn resolve_try_impl_for(&mut self, ty: Ty) -> Option<(hir_def::TraitId, Option<(Ty, Ty)>)> {
-        let path = path![core::ops::Try];
-        let trait_ = self.resolver.resolve_known_trait(self.db.upcast(), &path)?;
-
-        let trait_ref = TyBuilder::trait_ref(self.db, trait_).push(ty).build();
-        let substitution = trait_ref.substitution.clone();
-        self.push_obligation(trait_ref.clone().cast(Interner));
-
-        let trait_data = self.db.trait_data(trait_);
-        let output = trait_data.associated_type_by_name(&name![Output]);
-        let residual = trait_data.associated_type_by_name(&name![Residual]);
-
-        let output_ty = match output {
-            Some(output) => {
-                let output_ty = self.table.new_type_var();
-                let alias_eq = AliasEq {
-                    alias: AliasTy::Projection(ProjectionTy {
-                        associated_ty_id: to_assoc_type_id(output),
-                        substitution: substitution.clone(),
-                    }),
-                    ty: output_ty.clone(),
-                };
-                self.push_obligation(alias_eq.cast(Interner));
-                output_ty
-            }
-            None => self.err_ty(),
-        };
-        let residual_ty = match residual {
-            Some(residual) => {
-                let residual_ty = self.table.new_type_var();
-                let alias_eq = AliasEq {
-                    alias: AliasTy::Projection(ProjectionTy {
-                        associated_ty_id: to_assoc_type_id(residual),
-                        substitution,
-                    }),
-                    ty: residual_ty.clone(),
-                };
-                self.push_obligation(alias_eq.cast(Interner));
-                residual_ty
-            }
-            None => self.err_ty(),
-        };
-        // FIXME: We are doing the work twice here I think?
-        Some((
-            trait_,
-            self.table.try_obligation(trait_ref.cast(Interner)).map(|_| (output_ty, residual_ty)),
-        ))
-    }
 }
diff --git a/src/tools/rust-analyzer/crates/hir-ty/src/infer/path.rs b/src/tools/rust-analyzer/crates/hir-ty/src/infer/path.rs
index 7a4754cdc7bb..ebe9d6fb5e01 100644
--- a/src/tools/rust-analyzer/crates/hir-ty/src/infer/path.rs
+++ b/src/tools/rust-analyzer/crates/hir-ty/src/infer/path.rs
@@ -157,7 +157,7 @@ impl<'a> InferenceContext<'a> {
                     remaining_segments_for_ty,
                     true,
                 );
-                if let TyKind::Error = ty.kind(Interner) {
+                if ty.is_unknown() {
                     return None;
                 }
 
diff --git a/src/tools/rust-analyzer/crates/hir-ty/src/infer/unify.rs b/src/tools/rust-analyzer/crates/hir-ty/src/infer/unify.rs
index b00e3216b2d2..12f45f00f9c4 100644
--- a/src/tools/rust-analyzer/crates/hir-ty/src/infer/unify.rs
+++ b/src/tools/rust-analyzer/crates/hir-ty/src/infer/unify.rs
@@ -340,8 +340,8 @@ impl<'a> InferenceTable<'a> {
         self.resolve_with_fallback(t, &|_, _, d, _| d)
     }
 
-    /// Unify two types and register new trait goals that arise from that.
-    pub(crate) fn unify(&mut self, ty1: &Ty, ty2: &Ty) -> bool {
+    /// Unify two relatable values (e.g. `Ty`) and register new trait goals that arise from that.
+    pub(crate) fn unify<T: ?Sized + Zip<Interner>>(&mut self, ty1: &T, ty2: &T) -> bool {
         let result = match self.try_unify(ty1, ty2) {
             Ok(r) => r,
             Err(_) => return false,
@@ -350,9 +350,13 @@ impl<'a> InferenceTable<'a> {
         true
     }
 
-    /// Unify two types and return new trait goals arising from it, so the
+    /// Unify two relatable values (e.g. `Ty`) and return new trait goals arising from it, so the
     /// caller needs to deal with them.
-    pub(crate) fn try_unify<T: Zip<Interner>>(&mut self, t1: &T, t2: &T) -> InferResult<()> {
+    pub(crate) fn try_unify<T: ?Sized + Zip<Interner>>(
+        &mut self,
+        t1: &T,
+        t2: &T,
+    ) -> InferResult<()> {
         match self.var_unification_table.relate(
             Interner,
             &self.db,
diff --git a/src/tools/rust-analyzer/crates/hir-ty/src/lib.rs b/src/tools/rust-analyzer/crates/hir-ty/src/lib.rs
index c4b700cbce6d..b68c764bdca0 100644
--- a/src/tools/rust-analyzer/crates/hir-ty/src/lib.rs
+++ b/src/tools/rust-analyzer/crates/hir-ty/src/lib.rs
@@ -38,10 +38,12 @@ use std::sync::Arc;
 use chalk_ir::{
     fold::{Shift, TypeFoldable},
     interner::HasInterner,
-    NoSolution,
+    NoSolution, UniverseIndex,
 };
 use hir_def::{expr::ExprId, type_ref::Rawness, TypeOrConstParamId};
+use hir_expand::name;
 use itertools::Either;
+use traits::FnTrait;
 use utils::Generics;
 
 use crate::{consteval::unknown_const, db::HirDatabase, utils::generics};
@@ -81,7 +83,20 @@ pub type PlaceholderIndex = chalk_ir::PlaceholderIndex;
 pub type VariableKind = chalk_ir::VariableKind<Interner>;
 pub type VariableKinds = chalk_ir::VariableKinds<Interner>;
 pub type CanonicalVarKinds = chalk_ir::CanonicalVarKinds<Interner>;
+/// Represents generic parameters and an item bound by them. When the item has parent, the binders
+/// also contain the generic parameters for its parent. See chalk's documentation for details.
+///
+/// One thing to keep in mind when working with `Binders` (and `Substitution`s, which represent
+/// generic arguments) in rust-analyzer is that the ordering within *is* significant - the generic
+/// parameters/arguments for an item MUST come before those for its parent. This is to facilitate
+/// the integration with chalk-solve, which mildly puts constraints as such. See #13335 for its
+/// motivation in detail.
 pub type Binders<T> = chalk_ir::Binders<T>;
+/// Interned list of generic arguments for an item. When an item has parent, the `Substitution` for
+/// it contains generic arguments for both its parent and itself. See chalk's documentation for
+/// details.
+///
+/// See `Binders` for the constraint on the ordering.
 pub type Substitution = chalk_ir::Substitution<Interner>;
 pub type GenericArg = chalk_ir::GenericArg<Interner>;
 pub type GenericArgData = chalk_ir::GenericArgData<Interner>;
@@ -124,14 +139,6 @@ pub type ConstrainedSubst = chalk_ir::ConstrainedSubst<Interner>;
 pub type Guidance = chalk_solve::Guidance<Interner>;
 pub type WhereClause = chalk_ir::WhereClause<Interner>;
 
-// FIXME: get rid of this
-pub fn subst_prefix(s: &Substitution, n: usize) -> Substitution {
-    Substitution::from_iter(
-        Interner,
-        s.as_slice(Interner)[..std::cmp::min(s.len(Interner), n)].iter().cloned(),
-    )
-}
-
 /// Return an index of a parameter in the generic type parameter list by it's id.
 pub fn param_idx(db: &dyn HirDatabase, id: TypeOrConstParamId) -> Option<usize> {
     generics(db.upcast(), id.parent).param_idx(id)
@@ -203,6 +210,7 @@ pub(crate) fn make_binders<T: HasInterner<Interner = Interner>>(
 pub struct CallableSig {
     params_and_return: Arc<[Ty]>,
     is_varargs: bool,
+    safety: Safety,
 }
 
 has_interner!(CallableSig);
@@ -211,9 +219,14 @@ has_interner!(CallableSig);
 pub type PolyFnSig = Binders<CallableSig>;
 
 impl CallableSig {
-    pub fn from_params_and_return(mut params: Vec<Ty>, ret: Ty, is_varargs: bool) -> CallableSig {
+    pub fn from_params_and_return(
+        mut params: Vec<Ty>,
+        ret: Ty,
+        is_varargs: bool,
+        safety: Safety,
+    ) -> CallableSig {
         params.push(ret);
-        CallableSig { params_and_return: params.into(), is_varargs }
+        CallableSig { params_and_return: params.into(), is_varargs, safety }
     }
 
     pub fn from_fn_ptr(fn_ptr: &FnPointer) -> CallableSig {
@@ -230,13 +243,14 @@ impl CallableSig {
                 .map(|arg| arg.assert_ty_ref(Interner).clone())
                 .collect(),
             is_varargs: fn_ptr.sig.variadic,
+            safety: fn_ptr.sig.safety,
         }
     }
 
     pub fn to_fn_ptr(&self) -> FnPointer {
         FnPointer {
             num_binders: 0,
-            sig: FnSig { abi: (), safety: Safety::Safe, variadic: self.is_varargs },
+            sig: FnSig { abi: (), safety: self.safety, variadic: self.is_varargs },
             substitution: FnSubst(Substitution::from_iter(
                 Interner,
                 self.params_and_return.iter().cloned(),
@@ -261,7 +275,11 @@ impl TypeFoldable<Interner> for CallableSig {
     ) -> Result<Self, E> {
         let vec = self.params_and_return.to_vec();
         let folded = vec.try_fold_with(folder, outer_binder)?;
-        Ok(CallableSig { params_and_return: folded.into(), is_varargs: self.is_varargs })
+        Ok(CallableSig {
+            params_and_return: folded.into(),
+            is_varargs: self.is_varargs,
+            safety: self.safety,
+        })
     }
 }
 
@@ -382,7 +400,6 @@ pub(crate) fn fold_tys_and_consts<T: HasInterner<Interner = Interner> + TypeFold
 pub fn replace_errors_with_variables<T>(t: &T) -> Canonical<T>
 where
     T: HasInterner<Interner = Interner> + TypeFoldable<Interner> + Clone,
-    T: HasInterner<Interner = Interner>,
 {
     use chalk_ir::{
         fold::{FallibleTypeFolder, TypeSuperFoldable},
@@ -504,3 +521,68 @@ where
     });
     Canonical { value, binders: chalk_ir::CanonicalVarKinds::from_iter(Interner, kinds) }
 }
+
+pub fn callable_sig_from_fnonce(
+    self_ty: &Canonical<Ty>,
+    env: Arc<TraitEnvironment>,
+    db: &dyn HirDatabase,
+) -> Option<CallableSig> {
+    let krate = env.krate;
+    let fn_once_trait = FnTrait::FnOnce.get_id(db, krate)?;
+    let output_assoc_type = db.trait_data(fn_once_trait).associated_type_by_name(&name![Output])?;
+
+    let mut kinds = self_ty.binders.interned().to_vec();
+    let b = TyBuilder::trait_ref(db, fn_once_trait);
+    if b.remaining() != 2 {
+        return None;
+    }
+    let fn_once = b
+        .push(self_ty.value.clone())
+        .fill_with_bound_vars(DebruijnIndex::INNERMOST, kinds.len())
+        .build();
+    kinds.extend(fn_once.substitution.iter(Interner).skip(1).map(|x| {
+        let vk = match x.data(Interner) {
+            chalk_ir::GenericArgData::Ty(_) => {
+                chalk_ir::VariableKind::Ty(chalk_ir::TyVariableKind::General)
+            }
+            chalk_ir::GenericArgData::Lifetime(_) => chalk_ir::VariableKind::Lifetime,
+            chalk_ir::GenericArgData::Const(c) => {
+                chalk_ir::VariableKind::Const(c.data(Interner).ty.clone())
+            }
+        };
+        chalk_ir::WithKind::new(vk, UniverseIndex::ROOT)
+    }));
+
+    // FIXME: chalk refuses to solve `<Self as FnOnce<^0.0>>::Output == ^0.1`, so we first solve
+    // `<Self as FnOnce<^0.0>>` and then replace `^0.0` with the concrete argument tuple.
+    let trait_env = env.env.clone();
+    let obligation = InEnvironment { goal: fn_once.cast(Interner), environment: trait_env };
+    let canonical =
+        Canonical { binders: CanonicalVarKinds::from_iter(Interner, kinds), value: obligation };
+    let subst = match db.trait_solve(krate, canonical) {
+        Some(Solution::Unique(vars)) => vars.value.subst,
+        _ => return None,
+    };
+    let args = subst.at(Interner, self_ty.binders.interned().len()).ty(Interner)?;
+    let params = match args.kind(Interner) {
+        chalk_ir::TyKind::Tuple(_, subst) => {
+            subst.iter(Interner).filter_map(|arg| arg.ty(Interner).cloned()).collect::<Vec<_>>()
+        }
+        _ => return None,
+    };
+    if params.iter().any(|ty| ty.is_unknown()) {
+        return None;
+    }
+
+    let fn_once = TyBuilder::trait_ref(db, fn_once_trait)
+        .push(self_ty.value.clone())
+        .push(args.clone())
+        .build();
+    let projection =
+        TyBuilder::assoc_type_projection(db, output_assoc_type, Some(fn_once.substitution.clone()))
+            .build();
+
+    let ret_ty = db.normalize_projection(projection, env);
+
+    Some(CallableSig::from_params_and_return(params, ret_ty.clone(), false, Safety::Safe))
+}
diff --git a/src/tools/rust-analyzer/crates/hir-ty/src/lower.rs b/src/tools/rust-analyzer/crates/hir-ty/src/lower.rs
index 223d705b157b..baf9842d5fbf 100644
--- a/src/tools/rust-analyzer/crates/hir-ty/src/lower.rs
+++ b/src/tools/rust-analyzer/crates/hir-ty/src/lower.rs
@@ -227,13 +227,17 @@ impl<'a> TyLoweringContext<'a> {
                     .intern(Interner)
             }
             TypeRef::Placeholder => TyKind::Error.intern(Interner),
-            TypeRef::Fn(params, is_varargs) => {
+            &TypeRef::Fn(ref params, variadic, is_unsafe) => {
                 let substs = self.with_shifted_in(DebruijnIndex::ONE, |ctx| {
                     Substitution::from_iter(Interner, params.iter().map(|(_, tr)| ctx.lower_ty(tr)))
                 });
                 TyKind::Function(FnPointer {
                     num_binders: 0, // FIXME lower `for<'a> fn()` correctly
-                    sig: FnSig { abi: (), safety: Safety::Safe, variadic: *is_varargs },
+                    sig: FnSig {
+                        abi: (),
+                        safety: if is_unsafe { Safety::Unsafe } else { Safety::Safe },
+                        variadic,
+                    },
                     substitution: FnSubst(substs),
                 })
                 .intern(Interner)
@@ -447,12 +451,31 @@ impl<'a> TyLoweringContext<'a> {
                             .db
                             .trait_data(trait_ref.hir_trait_id())
                             .associated_type_by_name(segment.name);
+
                         match found {
                             Some(associated_ty) => {
-                                // FIXME handle type parameters on the segment
+                                // FIXME: `substs_from_path_segment()` pushes `TyKind::Error` for every parent
+                                // generic params. It's inefficient to splice the `Substitution`s, so we may want
+                                // that method to optionally take parent `Substitution` as we already know them at
+                                // this point (`trait_ref.substitution`).
+                                let substitution = self.substs_from_path_segment(
+                                    segment,
+                                    Some(associated_ty.into()),
+                                    false,
+                                    None,
+                                );
+                                let len_self =
+                                    generics(self.db.upcast(), associated_ty.into()).len_self();
+                                let substitution = Substitution::from_iter(
+                                    Interner,
+                                    substitution
+                                        .iter(Interner)
+                                        .take(len_self)
+                                        .chain(trait_ref.substitution.iter(Interner)),
+                                );
                                 TyKind::Alias(AliasTy::Projection(ProjectionTy {
                                     associated_ty_id: to_assoc_type_id(associated_ty),
-                                    substitution: trait_ref.substitution,
+                                    substitution,
                                 }))
                                 .intern(Interner)
                             }
@@ -590,36 +613,48 @@ impl<'a> TyLoweringContext<'a> {
             res,
             Some(segment.name.clone()),
             move |name, t, associated_ty| {
-                if name == segment.name {
-                    let substs = match self.type_param_mode {
-                        ParamLoweringMode::Placeholder => {
-                            // if we're lowering to placeholders, we have to put
-                            // them in now
-                            let generics = generics(
-                                self.db.upcast(),
-                                self.resolver
-                                    .generic_def()
-                                    .expect("there should be generics if there's a generic param"),
-                            );
-                            let s = generics.placeholder_subst(self.db);
-                            s.apply(t.substitution.clone(), Interner)
-                        }
-                        ParamLoweringMode::Variable => t.substitution.clone(),
-                    };
-                    // We need to shift in the bound vars, since
-                    // associated_type_shorthand_candidates does not do that
-                    let substs = substs.shifted_in_from(Interner, self.in_binders);
-                    // FIXME handle type parameters on the segment
-                    Some(
-                        TyKind::Alias(AliasTy::Projection(ProjectionTy {
-                            associated_ty_id: to_assoc_type_id(associated_ty),
-                            substitution: substs,
-                        }))
-                        .intern(Interner),
-                    )
-                } else {
-                    None
+                if name != segment.name {
+                    return None;
                 }
+
+                // FIXME: `substs_from_path_segment()` pushes `TyKind::Error` for every parent
+                // generic params. It's inefficient to splice the `Substitution`s, so we may want
+                // that method to optionally take parent `Substitution` as we already know them at
+                // this point (`t.substitution`).
+                let substs = self.substs_from_path_segment(
+                    segment.clone(),
+                    Some(associated_ty.into()),
+                    false,
+                    None,
+                );
+
+                let len_self = generics(self.db.upcast(), associated_ty.into()).len_self();
+
+                let substs = Substitution::from_iter(
+                    Interner,
+                    substs.iter(Interner).take(len_self).chain(t.substitution.iter(Interner)),
+                );
+
+                let substs = match self.type_param_mode {
+                    ParamLoweringMode::Placeholder => {
+                        // if we're lowering to placeholders, we have to put
+                        // them in now
+                        let generics = generics(self.db.upcast(), def);
+                        let s = generics.placeholder_subst(self.db);
+                        s.apply(substs, Interner)
+                    }
+                    ParamLoweringMode::Variable => substs,
+                };
+                // We need to shift in the bound vars, since
+                // associated_type_shorthand_candidates does not do that
+                let substs = substs.shifted_in_from(Interner, self.in_binders);
+                Some(
+                    TyKind::Alias(AliasTy::Projection(ProjectionTy {
+                        associated_ty_id: to_assoc_type_id(associated_ty),
+                        substitution: substs,
+                    }))
+                    .intern(Interner),
+                )
             },
         );
 
@@ -777,7 +812,15 @@ impl<'a> TyLoweringContext<'a> {
         // handle defaults. In expression or pattern path segments without
         // explicitly specified type arguments, missing type arguments are inferred
         // (i.e. defaults aren't used).
-        if !infer_args || had_explicit_args {
+        // Generic parameters for associated types are not supposed to have defaults, so we just
+        // ignore them.
+        let is_assoc_ty = if let GenericDefId::TypeAliasId(id) = def {
+            let container = id.lookup(self.db.upcast()).container;
+            matches!(container, ItemContainerId::TraitId(_))
+        } else {
+            false
+        };
+        if !is_assoc_ty && (!infer_args || had_explicit_args) {
             let defaults = self.db.generic_defaults(def);
             assert_eq!(total_len, defaults.len());
             let parent_from = item_len - substs.len();
@@ -966,9 +1009,28 @@ impl<'a> TyLoweringContext<'a> {
                     None => return SmallVec::new(),
                     Some(t) => t,
                 };
+                // FIXME: `substs_from_path_segment()` pushes `TyKind::Error` for every parent
+                // generic params. It's inefficient to splice the `Substitution`s, so we may want
+                // that method to optionally take parent `Substitution` as we already know them at
+                // this point (`super_trait_ref.substitution`).
+                let substitution = self.substs_from_path_segment(
+                    // FIXME: This is hack. We shouldn't really build `PathSegment` directly.
+                    PathSegment { name: &binding.name, args_and_bindings: binding.args.as_deref() },
+                    Some(associated_ty.into()),
+                    false, // this is not relevant
+                    Some(super_trait_ref.self_type_parameter(Interner)),
+                );
+                let self_params = generics(self.db.upcast(), associated_ty.into()).len_self();
+                let substitution = Substitution::from_iter(
+                    Interner,
+                    substitution
+                        .iter(Interner)
+                        .take(self_params)
+                        .chain(super_trait_ref.substitution.iter(Interner)),
+                );
                 let projection_ty = ProjectionTy {
                     associated_ty_id: to_assoc_type_id(associated_ty),
-                    substitution: super_trait_ref.substitution,
+                    substitution,
                 };
                 let mut preds: SmallVec<[_; 1]> = SmallVec::with_capacity(
                     binding.type_ref.as_ref().map_or(0, |_| 1) + binding.bounds.len(),
@@ -1515,7 +1577,12 @@ fn fn_sig_for_fn(db: &dyn HirDatabase, def: FunctionId) -> PolyFnSig {
         .with_type_param_mode(ParamLoweringMode::Variable);
     let ret = ctx_ret.lower_ty(&data.ret_type);
     let generics = generics(db.upcast(), def.into());
-    let sig = CallableSig::from_params_and_return(params, ret, data.is_varargs());
+    let sig = CallableSig::from_params_and_return(
+        params,
+        ret,
+        data.is_varargs(),
+        if data.has_unsafe_kw() { Safety::Unsafe } else { Safety::Safe },
+    );
     make_binders(db, &generics, sig)
 }
 
@@ -1559,7 +1626,7 @@ fn fn_sig_for_struct_constructor(db: &dyn HirDatabase, def: StructId) -> PolyFnS
         TyLoweringContext::new(db, &resolver).with_type_param_mode(ParamLoweringMode::Variable);
     let params = fields.iter().map(|(_, field)| ctx.lower_ty(&field.type_ref)).collect::<Vec<_>>();
     let (ret, binders) = type_for_adt(db, def.into()).into_value_and_skipped_binders();
-    Binders::new(binders, CallableSig::from_params_and_return(params, ret, false))
+    Binders::new(binders, CallableSig::from_params_and_return(params, ret, false, Safety::Safe))
 }
 
 /// Build the type of a tuple struct constructor.
@@ -1586,7 +1653,7 @@ fn fn_sig_for_enum_variant_constructor(db: &dyn HirDatabase, def: EnumVariantId)
         TyLoweringContext::new(db, &resolver).with_type_param_mode(ParamLoweringMode::Variable);
     let params = fields.iter().map(|(_, field)| ctx.lower_ty(&field.type_ref)).collect::<Vec<_>>();
     let (ret, binders) = type_for_adt(db, def.parent.into()).into_value_and_skipped_binders();
-    Binders::new(binders, CallableSig::from_params_and_return(params, ret, false))
+    Binders::new(binders, CallableSig::from_params_and_return(params, ret, false, Safety::Safe))
 }
 
 /// Build the type of a tuple enum variant constructor.
diff --git a/src/tools/rust-analyzer/crates/hir-ty/src/method_resolution.rs b/src/tools/rust-analyzer/crates/hir-ty/src/method_resolution.rs
index a79efeb6daa8..50859475e1d9 100644
--- a/src/tools/rust-analyzer/crates/hir-ty/src/method_resolution.rs
+++ b/src/tools/rust-analyzer/crates/hir-ty/src/method_resolution.rs
@@ -22,10 +22,10 @@ use crate::{
     from_foreign_def_id,
     infer::{unify::InferenceTable, Adjust, Adjustment, AutoBorrow, OverloadedDeref, PointerCast},
     primitive::{FloatTy, IntTy, UintTy},
-    static_lifetime,
+    static_lifetime, to_chalk_trait_id,
     utils::all_super_traits,
     AdtId, Canonical, CanonicalVarKinds, DebruijnIndex, ForeignDefId, InEnvironment, Interner,
-    Scalar, TraitEnvironment, TraitRefExt, Ty, TyBuilder, TyExt, TyKind,
+    Scalar, Substitution, TraitEnvironment, TraitRef, TraitRefExt, Ty, TyBuilder, TyExt, TyKind,
 };
 
 /// This is used as a key for indexing impls.
@@ -624,52 +624,76 @@ pub(crate) fn iterate_method_candidates<T>(
     slot
 }
 
+/// Looks up the impl method that actually runs for the trait method `func`.
+///
+/// Returns `func` if it's not a method defined in a trait or the lookup failed.
 pub fn lookup_impl_method(
-    self_ty: &Ty,
     db: &dyn HirDatabase,
     env: Arc<TraitEnvironment>,
-    trait_: TraitId,
+    func: FunctionId,
+    fn_subst: Substitution,
+) -> FunctionId {
+    let trait_id = match func.lookup(db.upcast()).container {
+        ItemContainerId::TraitId(id) => id,
+        _ => return func,
+    };
+    let trait_params = db.generic_params(trait_id.into()).type_or_consts.len();
+    let fn_params = fn_subst.len(Interner) - trait_params;
+    let trait_ref = TraitRef {
+        trait_id: to_chalk_trait_id(trait_id),
+        substitution: Substitution::from_iter(Interner, fn_subst.iter(Interner).skip(fn_params)),
+    };
+
+    let name = &db.function_data(func).name;
+    lookup_impl_method_for_trait_ref(trait_ref, db, env, name).unwrap_or(func)
+}
+
+fn lookup_impl_method_for_trait_ref(
+    trait_ref: TraitRef,
+    db: &dyn HirDatabase,
+    env: Arc<TraitEnvironment>,
     name: &Name,
 ) -> Option<FunctionId> {
-    let self_ty_fp = TyFingerprint::for_trait_impl(self_ty)?;
-    let trait_impls = db.trait_impls_in_deps(env.krate);
-    let impls = trait_impls.for_trait_and_self_ty(trait_, self_ty_fp);
-    let mut table = InferenceTable::new(db, env.clone());
-    find_matching_impl(impls, &mut table, &self_ty).and_then(|data| {
-        data.items.iter().find_map(|it| match it {
-            AssocItemId::FunctionId(f) => (db.function_data(*f).name == *name).then(|| *f),
-            _ => None,
-        })
+    let self_ty = trait_ref.self_type_parameter(Interner);
+    let self_ty_fp = TyFingerprint::for_trait_impl(&self_ty)?;
+    let impls = db.trait_impls_in_deps(env.krate);
+    let impls = impls.for_trait_and_self_ty(trait_ref.hir_trait_id(), self_ty_fp);
+
+    let table = InferenceTable::new(db, env);
+
+    let impl_data = find_matching_impl(impls, table, trait_ref)?;
+    impl_data.items.iter().find_map(|it| match it {
+        AssocItemId::FunctionId(f) => (db.function_data(*f).name == *name).then(|| *f),
+        _ => None,
     })
 }
 
 fn find_matching_impl(
     mut impls: impl Iterator<Item = ImplId>,
-    table: &mut InferenceTable<'_>,
-    self_ty: &Ty,
+    mut table: InferenceTable<'_>,
+    actual_trait_ref: TraitRef,
 ) -> Option<Arc<ImplData>> {
     let db = table.db;
     loop {
         let impl_ = impls.next()?;
         let r = table.run_in_snapshot(|table| {
             let impl_data = db.impl_data(impl_);
-            let substs =
+            let impl_substs =
                 TyBuilder::subst_for_def(db, impl_, None).fill_with_inference_vars(table).build();
-            let impl_ty = db.impl_self_ty(impl_).substitute(Interner, &substs);
+            let trait_ref = db
+                .impl_trait(impl_)
+                .expect("non-trait method in find_matching_impl")
+                .substitute(Interner, &impl_substs);
 
-            table
-                .unify(self_ty, &impl_ty)
-                .then(|| {
-                    let wh_goals =
-                        crate::chalk_db::convert_where_clauses(db, impl_.into(), &substs)
-                            .into_iter()
-                            .map(|b| b.cast(Interner));
+            if !table.unify(&trait_ref, &actual_trait_ref) {
+                return None;
+            }
 
-                    let goal = crate::Goal::all(Interner, wh_goals);
-
-                    table.try_obligation(goal).map(|_| impl_data)
-                })
-                .flatten()
+            let wcs = crate::chalk_db::convert_where_clauses(db, impl_.into(), &impl_substs)
+                .into_iter()
+                .map(|b| b.cast(Interner));
+            let goal = crate::Goal::all(Interner, wcs);
+            table.try_obligation(goal).map(|_| impl_data)
         });
         if r.is_some() {
             break r;
@@ -1111,24 +1135,6 @@ pub fn resolve_indexing_op(
     }
     None
 }
-/// Returns the receiver type for the try branch trait call.
-pub fn resolve_branch_op(
-    db: &dyn HirDatabase,
-    env: Arc<TraitEnvironment>,
-    ty: Canonical<Ty>,
-    try_trait: TraitId,
-) -> Option<ReceiverAdjustments> {
-    let mut table = InferenceTable::new(db, env.clone());
-    let ty = table.instantiate_canonical(ty);
-    let (deref_chain, adj) = autoderef_method_receiver(&mut table, ty);
-    for (ty, adj) in deref_chain.into_iter().zip(adj) {
-        let goal = generic_implements_goal(db, env.clone(), try_trait, &ty);
-        if db.trait_solve(env.krate, goal.cast(Interner)).is_some() {
-            return Some(adj);
-        }
-    }
-    None
-}
 
 macro_rules! check_that {
     ($cond:expr) => {
@@ -1232,7 +1238,7 @@ fn is_valid_fn_candidate(
             let expected_receiver =
                 sig.map(|s| s.params()[0].clone()).substitute(Interner, &fn_subst);
 
-            check_that!(table.unify(&receiver_ty, &expected_receiver));
+            check_that!(table.unify(receiver_ty, &expected_receiver));
         }
 
         if let ItemContainerId::ImplId(impl_id) = container {
diff --git a/src/tools/rust-analyzer/crates/hir-ty/src/tests/coercion.rs b/src/tools/rust-analyzer/crates/hir-ty/src/tests/coercion.rs
index d301595bcd98..7e3aecc2ae0a 100644
--- a/src/tools/rust-analyzer/crates/hir-ty/src/tests/coercion.rs
+++ b/src/tools/rust-analyzer/crates/hir-ty/src/tests/coercion.rs
@@ -122,6 +122,23 @@ fn test() {
     )
 }
 
+#[test]
+fn if_else_adjust_for_branches_discard_type_var() {
+    check_no_mismatches(
+        r#"
+fn test() {
+    let f = || {
+        if true {
+            &""
+        } else {
+            ""
+        }
+    };
+}
+"#,
+    );
+}
+
 #[test]
 fn match_first_coerce() {
     check_no_mismatches(
@@ -182,6 +199,22 @@ fn test() {
     );
 }
 
+#[test]
+fn match_adjust_for_branches_discard_type_var() {
+    check_no_mismatches(
+        r#"
+fn test() {
+    let f = || {
+        match 0i32 {
+            0i32 => &"",
+            _ => "",
+        }
+    };
+}
+"#,
+    );
+}
+
 #[test]
 fn return_coerce_unknown() {
     check_types(
@@ -357,7 +390,7 @@ fn test() {
     let f: fn(u32) -> isize = foo;
                            // ^^^ adjustments: Pointer(ReifyFnPointer)
     let f: unsafe fn(u32) -> isize = foo;
-                                  // ^^^ adjustments: Pointer(ReifyFnPointer)
+                                  // ^^^ adjustments: Pointer(ReifyFnPointer), Pointer(UnsafeFnPointer)
 }",
     );
 }
@@ -388,7 +421,10 @@ fn coerce_closure_to_fn_ptr() {
     check_no_mismatches(
         r"
 fn test() {
-    let f: fn(u32) -> isize = |x| { 1 };
+    let f: fn(u32) -> u32 = |x| x;
+                         // ^^^^^ adjustments: Pointer(ClosureFnPointer(Safe))
+    let f: unsafe fn(u32) -> u32 = |x| x;
+                                // ^^^^^ adjustments: Pointer(ClosureFnPointer(Unsafe))
 }",
     );
 }
diff --git a/src/tools/rust-analyzer/crates/hir-ty/src/tests/display_source_code.rs b/src/tools/rust-analyzer/crates/hir-ty/src/tests/display_source_code.rs
index 8a8ff08cfe8c..425432479e81 100644
--- a/src/tools/rust-analyzer/crates/hir-ty/src/tests/display_source_code.rs
+++ b/src/tools/rust-analyzer/crates/hir-ty/src/tests/display_source_code.rs
@@ -196,3 +196,34 @@ fn test(
 "#,
     );
 }
+
+#[test]
+fn projection_type_correct_arguments_order() {
+    check_types_source_code(
+        r#"
+trait Foo<T> {
+    type Assoc<U>;
+}
+fn f<T: Foo<i32>>(a: T::Assoc<usize>) {
+    a;
+  //^ <T as Foo<i32>>::Assoc<usize>
+}
+"#,
+    );
+}
+
+#[test]
+fn generic_associated_type_binding_in_impl_trait() {
+    check_types_source_code(
+        r#"
+//- minicore: sized
+trait Foo<T> {
+    type Assoc<U>;
+}
+fn f(a: impl Foo<i8, Assoc<i16> = i32>) {
+    a;
+  //^ impl Foo<i8, Assoc<i16> = i32>
+}
+        "#,
+    );
+}
diff --git a/src/tools/rust-analyzer/crates/hir-ty/src/tests/traits.rs b/src/tools/rust-analyzer/crates/hir-ty/src/tests/traits.rs
index b91172e33422..7d42b8b9bc8d 100644
--- a/src/tools/rust-analyzer/crates/hir-ty/src/tests/traits.rs
+++ b/src/tools/rust-analyzer/crates/hir-ty/src/tests/traits.rs
@@ -162,16 +162,98 @@ fn test() {
     );
 }
 
+#[test]
+fn infer_try() {
+    check_types(
+        r#"
+//- /main.rs crate:main deps:core
+fn test() {
+    let r: Result<i32, u64> = Result::Ok(1);
+    let v = r?;
+    v;
+} //^ i32
+
+//- /core.rs crate:core
+pub mod ops {
+    pub trait Try {
+        type Ok;
+        type Error;
+    }
+}
+
+pub mod result {
+    pub enum Result<O, E> {
+        Ok(O),
+        Err(E)
+    }
+
+    impl<O, E> crate::ops::Try for Result<O, E> {
+        type Ok = O;
+        type Error = E;
+    }
+}
+
+pub mod prelude {
+    pub mod rust_2018 {
+        pub use crate::{result::*, ops::*};
+    }
+}
+"#,
+    );
+}
+
 #[test]
 fn infer_try_trait_v2() {
     check_types(
         r#"
-//- minicore: try
-fn test() -> core::ops::ControlFlow<u32, f32> {
-    let r: core::ops::ControlFlow<u32, f32> = core::ops::ControlFlow::Continue(1.0);
+//- /main.rs crate:main deps:core
+fn test() {
+    let r: Result<i32, u64> = Result::Ok(1);
     let v = r?;
-      //^ f32
-    r
+    v;
+} //^ i32
+
+//- /core.rs crate:core
+mod ops {
+    mod try_trait {
+        pub trait Try: FromResidual {
+            type Output;
+            type Residual;
+        }
+        pub trait FromResidual<R = <Self as Try>::Residual> {}
+    }
+
+    pub use self::try_trait::FromResidual;
+    pub use self::try_trait::Try;
+}
+
+mod convert {
+    pub trait From<T> {}
+    impl<T> From<T> for T {}
+}
+
+pub mod result {
+    use crate::convert::From;
+    use crate::ops::{Try, FromResidual};
+
+    pub enum Infallible {}
+    pub enum Result<O, E> {
+        Ok(O),
+        Err(E)
+    }
+
+    impl<O, E> Try for Result<O, E> {
+        type Output = O;
+        type Error = Result<Infallible, E>;
+    }
+
+    impl<T, E, F: From<E>> FromResidual<Result<Infallible, E>> for Result<T, F> {}
+}
+
+pub mod prelude {
+    pub mod rust_2018 {
+        pub use crate::result::*;
+    }
 }
 "#,
     );
@@ -3881,3 +3963,124 @@ fn g(t: &(dyn T + Send)) {
         "#,
     );
 }
+
+#[test]
+fn gats_in_path() {
+    check_types(
+        r#"
+//- minicore: deref
+use core::ops::Deref;
+trait PointerFamily {
+    type Pointer<T>: Deref<Target = T>;
+}
+
+fn f<P: PointerFamily>(p: P::Pointer<i32>) {
+    let a = *p;
+      //^ i32
+}
+fn g<P: PointerFamily>(p: <P as PointerFamily>::Pointer<i32>) {
+    let a = *p;
+      //^ i32
+}
+        "#,
+    );
+}
+
+#[test]
+fn gats_with_impl_trait() {
+    // FIXME: the last function (`fn i()`) is not valid Rust as of this writing because you cannot
+    // specify the same associated type multiple times even if their arguments are different (c.f.
+    // `fn h()`, which is valid). Reconsider how to treat these invalid types.
+    check_types(
+        r#"
+//- minicore: deref
+use core::ops::Deref;
+
+trait Trait {
+    type Assoc<T>: Deref<Target = T>;
+    fn get<U>(&self) -> Self::Assoc<U>;
+}
+
+fn f<T>(v: impl Trait) {
+    let a = v.get::<i32>().deref();
+      //^ &i32
+    let a = v.get::<T>().deref();
+      //^ &T
+}
+fn g<'a, T: 'a>(v: impl Trait<Assoc<T> = &'a T>) {
+    let a = v.get::<T>();
+      //^ &T
+    let a = v.get::<()>();
+      //^ Trait::Assoc<(), impl Trait<Assoc<T> = &T>>
+}
+fn h<'a>(v: impl Trait<Assoc<i32> = &'a i32> + Trait<Assoc<i64> = &'a i64>) {
+    let a = v.get::<i32>();
+      //^ &i32
+    let a = v.get::<i64>();
+      //^ &i64
+}
+fn i<'a>(v: impl Trait<Assoc<i32> = &'a i32, Assoc<i64> = &'a i64>) {
+    let a = v.get::<i32>();
+      //^ &i32
+    let a = v.get::<i64>();
+      //^ &i64
+}
+    "#,
+    );
+}
+
+#[test]
+fn gats_with_dyn() {
+    // This test is here to keep track of how we infer things despite traits with GATs being not
+    // object-safe currently.
+    // FIXME: reconsider how to treat these invalid types.
+    check_infer_with_mismatches(
+        r#"
+//- minicore: deref
+use core::ops::Deref;
+
+trait Trait {
+    type Assoc<T>: Deref<Target = T>;
+    fn get<U>(&self) -> Self::Assoc<U>;
+}
+
+fn f<'a>(v: &dyn Trait<Assoc<i32> = &'a i32>) {
+    v.get::<i32>().deref();
+}
+    "#,
+        expect![[r#"
+            90..94 'self': &Self
+            127..128 'v': &(dyn Trait<Assoc<i32> = &i32>)
+            164..195 '{     ...f(); }': ()
+            170..171 'v': &(dyn Trait<Assoc<i32> = &i32>)
+            170..184 'v.get::<i32>()': &i32
+            170..192 'v.get:...eref()': &i32
+        "#]],
+    );
+}
+
+#[test]
+fn gats_in_associated_type_binding() {
+    check_types(
+        r#"
+trait Trait {
+    type Assoc<T>;
+    fn get<U>(&self) -> Self::Assoc<U>;
+}
+
+fn f<T>(t: T)
+where
+    T: Trait<Assoc<i32> = u32>,
+    T: Trait<Assoc<isize> = usize>,
+{
+    let a = t.get::<i32>();
+      //^ u32
+    let a = t.get::<isize>();
+      //^ usize
+    let a = t.get::<()>();
+      //^ Trait::Assoc<(), T>
+}
+
+    "#,
+    );
+}
diff --git a/src/tools/rust-analyzer/crates/hir-ty/src/tls.rs b/src/tools/rust-analyzer/crates/hir-ty/src/tls.rs
index 547850b021c3..92711a24fe39 100644
--- a/src/tools/rust-analyzer/crates/hir-ty/src/tls.rs
+++ b/src/tools/rust-analyzer/crates/hir-ty/src/tls.rs
@@ -5,7 +5,7 @@ use itertools::Itertools;
 
 use crate::{
     chalk_db, db::HirDatabase, from_assoc_type_id, from_chalk_trait_id, mapping::from_chalk,
-    CallableDefId, Interner,
+    CallableDefId, Interner, ProjectionTyExt,
 };
 use hir_def::{AdtId, ItemContainerId, Lookup, TypeAliasId};
 
@@ -63,17 +63,31 @@ impl DebugContext<'_> {
             ItemContainerId::TraitId(t) => t,
             _ => panic!("associated type not in trait"),
         };
-        let trait_data = self.0.trait_data(trait_);
-        let params = projection_ty.substitution.as_slice(Interner);
-        write!(fmt, "<{:?} as {}", &params[0], trait_data.name,)?;
-        if params.len() > 1 {
+        let trait_name = &self.0.trait_data(trait_).name;
+        let trait_ref = projection_ty.trait_ref(self.0);
+        let trait_params = trait_ref.substitution.as_slice(Interner);
+        let self_ty = trait_ref.self_type_parameter(Interner);
+        write!(fmt, "<{:?} as {}", self_ty, trait_name)?;
+        if trait_params.len() > 1 {
             write!(
                 fmt,
                 "<{}>",
-                &params[1..].iter().format_with(", ", |x, f| f(&format_args!("{:?}", x))),
+                trait_params[1..].iter().format_with(", ", |x, f| f(&format_args!("{:?}", x))),
             )?;
         }
-        write!(fmt, ">::{}", type_alias_data.name)
+        write!(fmt, ">::{}", type_alias_data.name)?;
+
+        let proj_params_count = projection_ty.substitution.len(Interner) - trait_params.len();
+        let proj_params = &projection_ty.substitution.as_slice(Interner)[..proj_params_count];
+        if !proj_params.is_empty() {
+            write!(
+                fmt,
+                "<{}>",
+                proj_params.iter().format_with(", ", |x, f| f(&format_args!("{:?}", x))),
+            )?;
+        }
+
+        Ok(())
     }
 
     pub(crate) fn debug_fn_def_id(
diff --git a/src/tools/rust-analyzer/crates/hir/src/diagnostics.rs b/src/tools/rust-analyzer/crates/hir/src/diagnostics.rs
index 6c8b3088adc0..c5dc60f1ec5f 100644
--- a/src/tools/rust-analyzer/crates/hir/src/diagnostics.rs
+++ b/src/tools/rust-analyzer/crates/hir/src/diagnostics.rs
@@ -6,7 +6,7 @@
 use base_db::CrateId;
 use cfg::{CfgExpr, CfgOptions};
 use either::Either;
-use hir_def::{path::ModPath, TraitId};
+use hir_def::path::ModPath;
 use hir_expand::{name::Name, HirFileId, InFile};
 use syntax::{ast, AstPtr, SyntaxNodePtr, TextRange};
 
@@ -33,7 +33,6 @@ diagnostics![
     BreakOutsideOfLoop,
     InactiveCode,
     IncorrectCase,
-    IncorrectTryExpr,
     InvalidDeriveTarget,
     MacroError,
     MalformedDerive,
@@ -41,7 +40,6 @@ diagnostics![
     MissingFields,
     MissingMatchArms,
     MissingUnsafe,
-    NotImplemented,
     NoSuchField,
     ReplaceFilterMapNextWithFindMap,
     TypeMismatch,
@@ -155,16 +153,6 @@ pub struct MismatchedArgCount {
     pub expected: usize,
     pub found: usize,
 }
-#[derive(Debug)]
-pub struct IncorrectTryExpr {
-    pub expr: InFile<AstPtr<ast::Expr>>,
-}
-#[derive(Debug)]
-pub struct NotImplemented {
-    pub expr: InFile<AstPtr<ast::Expr>>,
-    pub trait_: TraitId,
-    pub ty: Type,
-}
 
 #[derive(Debug)]
 pub struct MissingMatchArms {
diff --git a/src/tools/rust-analyzer/crates/hir/src/lib.rs b/src/tools/rust-analyzer/crates/hir/src/lib.rs
index e6c5c6b58339..cbd9bf32a548 100644
--- a/src/tools/rust-analyzer/crates/hir/src/lib.rs
+++ b/src/tools/rust-analyzer/crates/hir/src/lib.rs
@@ -81,12 +81,11 @@ use crate::db::{DefDatabase, HirDatabase};
 pub use crate::{
     attrs::{HasAttrs, Namespace},
     diagnostics::{
-        AnyDiagnostic, BreakOutsideOfLoop, InactiveCode, IncorrectCase, IncorrectTryExpr,
-        InvalidDeriveTarget, MacroError, MalformedDerive, MismatchedArgCount, MissingFields,
-        MissingMatchArms, MissingUnsafe, NoSuchField, NotImplemented,
-        ReplaceFilterMapNextWithFindMap, TypeMismatch, UnimplementedBuiltinMacro,
-        UnresolvedExternCrate, UnresolvedImport, UnresolvedMacroCall, UnresolvedModule,
-        UnresolvedProcMacro,
+        AnyDiagnostic, BreakOutsideOfLoop, InactiveCode, IncorrectCase, InvalidDeriveTarget,
+        MacroError, MalformedDerive, MismatchedArgCount, MissingFields, MissingMatchArms,
+        MissingUnsafe, NoSuchField, ReplaceFilterMapNextWithFindMap, TypeMismatch,
+        UnimplementedBuiltinMacro, UnresolvedExternCrate, UnresolvedImport, UnresolvedMacroCall,
+        UnresolvedModule, UnresolvedProcMacro,
     },
     has_source::HasSource,
     semantics::{PathResolution, Semantics, SemanticsScope, TypeInfo, VisibleTraits},
@@ -1283,45 +1282,30 @@ impl DefWithBody {
         let infer = db.infer(self.into());
         let source_map = Lazy::new(|| db.body_with_source_map(self.into()).1);
         for d in &infer.diagnostics {
-            match *d {
+            match d {
                 hir_ty::InferenceDiagnostic::NoSuchField { expr } => {
-                    let field = source_map.field_syntax(expr);
+                    let field = source_map.field_syntax(*expr);
                     acc.push(NoSuchField { field }.into())
                 }
-                hir_ty::InferenceDiagnostic::BreakOutsideOfLoop { expr, is_break } => {
+                &hir_ty::InferenceDiagnostic::BreakOutsideOfLoop { expr, is_break } => {
                     let expr = source_map
                         .expr_syntax(expr)
                         .expect("break outside of loop in synthetic syntax");
                     acc.push(BreakOutsideOfLoop { expr, is_break }.into())
                 }
                 hir_ty::InferenceDiagnostic::MismatchedArgCount { call_expr, expected, found } => {
-                    match source_map.expr_syntax(call_expr) {
+                    match source_map.expr_syntax(*call_expr) {
                         Ok(source_ptr) => acc.push(
                             MismatchedArgCount {
                                 call_expr: source_ptr,
-                                expected: expected,
-                                found: found,
+                                expected: *expected,
+                                found: *found,
                             }
                             .into(),
                         ),
                         Err(SyntheticSyntax) => (),
                     }
                 }
-                hir_ty::InferenceDiagnostic::IncorrectTryTarget { expr } => {
-                    let expr = source_map.expr_syntax(expr).expect("try in synthetic syntax");
-                    acc.push(IncorrectTryExpr { expr }.into())
-                }
-                hir_ty::InferenceDiagnostic::DoesNotImplement { expr, trait_, ref ty } => {
-                    let expr = source_map.expr_syntax(expr).expect("try in synthetic syntax");
-                    acc.push(
-                        NotImplemented {
-                            expr,
-                            trait_,
-                            ty: Type::new(db, DefWithBodyId::from(self), ty.clone()),
-                        }
-                        .into(),
-                    )
-                }
             }
         }
         for (expr, mismatch) in infer.expr_type_mismatches() {
@@ -3011,7 +2995,17 @@ impl Type {
         let callee = match self.ty.kind(Interner) {
             TyKind::Closure(id, _) => Callee::Closure(*id),
             TyKind::Function(_) => Callee::FnPtr,
-            _ => Callee::Def(self.ty.callable_def(db)?),
+            TyKind::FnDef(..) => Callee::Def(self.ty.callable_def(db)?),
+            _ => {
+                let ty = hir_ty::replace_errors_with_variables(&self.ty);
+                let sig = hir_ty::callable_sig_from_fnonce(&ty, self.env.clone(), db)?;
+                return Some(Callable {
+                    ty: self.clone(),
+                    sig,
+                    callee: Callee::Other,
+                    is_bound_method: false,
+                });
+            }
         };
 
         let sig = self.ty.callable_sig(db)?;
@@ -3480,6 +3474,7 @@ enum Callee {
     Def(CallableDefId),
     Closure(ClosureId),
     FnPtr,
+    Other,
 }
 
 pub enum CallableKind {
@@ -3488,6 +3483,8 @@ pub enum CallableKind {
     TupleEnumVariant(Variant),
     Closure,
     FnPtr,
+    /// Some other type that implements `FnOnce`.
+    Other,
 }
 
 impl Callable {
@@ -3499,6 +3496,7 @@ impl Callable {
             Def(CallableDefId::EnumVariantId(it)) => CallableKind::TupleEnumVariant(it.into()),
             Closure(_) => CallableKind::Closure,
             FnPtr => CallableKind::FnPtr,
+            Other => CallableKind::Other,
         }
     }
     pub fn receiver_param(&self, db: &dyn HirDatabase) -> Option<ast::SelfParam> {
diff --git a/src/tools/rust-analyzer/crates/hir/src/source_analyzer.rs b/src/tools/rust-analyzer/crates/hir/src/source_analyzer.rs
index 07bae2b38c79..f86c57100536 100644
--- a/src/tools/rust-analyzer/crates/hir/src/source_analyzer.rs
+++ b/src/tools/rust-analyzer/crates/hir/src/source_analyzer.rs
@@ -270,7 +270,7 @@ impl SourceAnalyzer {
         let expr_id = self.expr_id(db, &call.clone().into())?;
         let (f_in_trait, substs) = self.infer.as_ref()?.method_resolution(expr_id)?;
 
-        Some(self.resolve_impl_method_or_trait_def(db, f_in_trait, &substs))
+        Some(self.resolve_impl_method_or_trait_def(db, f_in_trait, substs))
     }
 
     pub(crate) fn resolve_await_to_poll(
@@ -311,7 +311,7 @@ impl SourceAnalyzer {
         // HACK: subst for `poll()` coincides with that for `Future` because `poll()` itself
         // doesn't have any generic parameters, so we skip building another subst for `poll()`.
         let substs = hir_ty::TyBuilder::subst_for_def(db, future_trait, None).push(ty).build();
-        Some(self.resolve_impl_method_or_trait_def(db, poll_fn, &substs))
+        Some(self.resolve_impl_method_or_trait_def(db, poll_fn, substs))
     }
 
     pub(crate) fn resolve_prefix_expr(
@@ -331,7 +331,7 @@ impl SourceAnalyzer {
         // don't have any generic parameters, so we skip building another subst for the methods.
         let substs = hir_ty::TyBuilder::subst_for_def(db, op_trait, None).push(ty.clone()).build();
 
-        Some(self.resolve_impl_method_or_trait_def(db, op_fn, &substs))
+        Some(self.resolve_impl_method_or_trait_def(db, op_fn, substs))
     }
 
     pub(crate) fn resolve_index_expr(
@@ -351,7 +351,7 @@ impl SourceAnalyzer {
             .push(base_ty.clone())
             .push(index_ty.clone())
             .build();
-        Some(self.resolve_impl_method_or_trait_def(db, op_fn, &substs))
+        Some(self.resolve_impl_method_or_trait_def(db, op_fn, substs))
     }
 
     pub(crate) fn resolve_bin_expr(
@@ -372,7 +372,7 @@ impl SourceAnalyzer {
             .push(rhs.clone())
             .build();
 
-        Some(self.resolve_impl_method_or_trait_def(db, op_fn, &substs))
+        Some(self.resolve_impl_method_or_trait_def(db, op_fn, substs))
     }
 
     pub(crate) fn resolve_try_expr(
@@ -392,7 +392,7 @@ impl SourceAnalyzer {
         // doesn't have any generic parameters, so we skip building another subst for `branch()`.
         let substs = hir_ty::TyBuilder::subst_for_def(db, op_trait, None).push(ty.clone()).build();
 
-        Some(self.resolve_impl_method_or_trait_def(db, op_fn, &substs))
+        Some(self.resolve_impl_method_or_trait_def(db, op_fn, substs))
     }
 
     pub(crate) fn resolve_field(
@@ -487,9 +487,9 @@ impl SourceAnalyzer {
 
         let mut prefer_value_ns = false;
         let resolved = (|| {
+            let infer = self.infer.as_deref()?;
             if let Some(path_expr) = parent().and_then(ast::PathExpr::cast) {
                 let expr_id = self.expr_id(db, &path_expr.into())?;
-                let infer = self.infer.as_ref()?;
                 if let Some(assoc) = infer.assoc_resolutions_for_expr(expr_id) {
                     let assoc = match assoc {
                         AssocItemId::FunctionId(f_in_trait) => {
@@ -497,9 +497,12 @@ impl SourceAnalyzer {
                                 None => assoc,
                                 Some(func_ty) => {
                                     if let TyKind::FnDef(_fn_def, subs) = func_ty.kind(Interner) {
-                                        self.resolve_impl_method(db, f_in_trait, subs)
-                                            .map(AssocItemId::FunctionId)
-                                            .unwrap_or(assoc)
+                                        self.resolve_impl_method_or_trait_def(
+                                            db,
+                                            f_in_trait,
+                                            subs.clone(),
+                                        )
+                                        .into()
                                     } else {
                                         assoc
                                     }
@@ -520,18 +523,18 @@ impl SourceAnalyzer {
                 prefer_value_ns = true;
             } else if let Some(path_pat) = parent().and_then(ast::PathPat::cast) {
                 let pat_id = self.pat_id(&path_pat.into())?;
-                if let Some(assoc) = self.infer.as_ref()?.assoc_resolutions_for_pat(pat_id) {
+                if let Some(assoc) = infer.assoc_resolutions_for_pat(pat_id) {
                     return Some(PathResolution::Def(AssocItem::from(assoc).into()));
                 }
                 if let Some(VariantId::EnumVariantId(variant)) =
-                    self.infer.as_ref()?.variant_resolution_for_pat(pat_id)
+                    infer.variant_resolution_for_pat(pat_id)
                 {
                     return Some(PathResolution::Def(ModuleDef::Variant(variant.into())));
                 }
             } else if let Some(rec_lit) = parent().and_then(ast::RecordExpr::cast) {
                 let expr_id = self.expr_id(db, &rec_lit.into())?;
                 if let Some(VariantId::EnumVariantId(variant)) =
-                    self.infer.as_ref()?.variant_resolution_for_expr(expr_id)
+                    infer.variant_resolution_for_expr(expr_id)
                 {
                     return Some(PathResolution::Def(ModuleDef::Variant(variant.into())));
                 }
@@ -541,8 +544,7 @@ impl SourceAnalyzer {
                     || parent().and_then(ast::TupleStructPat::cast).map(ast::Pat::from);
                 if let Some(pat) = record_pat.or_else(tuple_struct_pat) {
                     let pat_id = self.pat_id(&pat)?;
-                    let variant_res_for_pat =
-                        self.infer.as_ref()?.variant_resolution_for_pat(pat_id);
+                    let variant_res_for_pat = infer.variant_resolution_for_pat(pat_id);
                     if let Some(VariantId::EnumVariantId(variant)) = variant_res_for_pat {
                         return Some(PathResolution::Def(ModuleDef::Variant(variant.into())));
                     }
@@ -780,37 +782,22 @@ impl SourceAnalyzer {
         false
     }
 
-    fn resolve_impl_method(
-        &self,
-        db: &dyn HirDatabase,
-        func: FunctionId,
-        substs: &Substitution,
-    ) -> Option<FunctionId> {
-        let impled_trait = match func.lookup(db.upcast()).container {
-            ItemContainerId::TraitId(trait_id) => trait_id,
-            _ => return None,
-        };
-        if substs.is_empty(Interner) {
-            return None;
-        }
-        let self_ty = substs.at(Interner, 0).ty(Interner)?;
-        let krate = self.resolver.krate();
-        let trait_env = self.resolver.body_owner()?.as_generic_def_id().map_or_else(
-            || Arc::new(hir_ty::TraitEnvironment::empty(krate)),
-            |d| db.trait_environment(d),
-        );
-
-        let fun_data = db.function_data(func);
-        method_resolution::lookup_impl_method(self_ty, db, trait_env, impled_trait, &fun_data.name)
-    }
-
     fn resolve_impl_method_or_trait_def(
         &self,
         db: &dyn HirDatabase,
         func: FunctionId,
-        substs: &Substitution,
+        substs: Substitution,
     ) -> FunctionId {
-        self.resolve_impl_method(db, func, substs).unwrap_or(func)
+        let krate = self.resolver.krate();
+        let owner = match self.resolver.body_owner() {
+            Some(it) => it,
+            None => return func,
+        };
+        let env = owner.as_generic_def_id().map_or_else(
+            || Arc::new(hir_ty::TraitEnvironment::empty(krate)),
+            |d| db.trait_environment(d),
+        );
+        method_resolution::lookup_impl_method(db, env, func, substs)
     }
 
     fn lang_trait_fn(
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/assist_config.rs b/src/tools/rust-analyzer/crates/ide-assists/src/assist_config.rs
index 60d1588a44e5..b273ebc85a50 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/assist_config.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/assist_config.rs
@@ -14,4 +14,5 @@ pub struct AssistConfig {
     pub allowed: Option<Vec<AssistKind>>,
     pub insert_use: InsertUseConfig,
     pub prefer_no_std: bool,
+    pub assist_emit_must_use: bool,
 }
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/add_explicit_type.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/add_explicit_type.rs
index bfa9759ec84b..b5f99726fe1c 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/add_explicit_type.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/add_explicit_type.rs
@@ -69,14 +69,14 @@ pub(crate) fn add_explicit_type(acc: &mut Assists, ctx: &AssistContext<'_>) -> O
     let inferred_type = ty.display_source_code(ctx.db(), module.into()).ok()?;
     acc.add(
         AssistId("add_explicit_type", AssistKind::RefactorRewrite),
-        format!("Insert explicit type `{}`", inferred_type),
+        format!("Insert explicit type `{inferred_type}`"),
         pat_range,
         |builder| match ascribed_ty {
             Some(ascribed_ty) => {
                 builder.replace(ascribed_ty.syntax().text_range(), inferred_type);
             }
             None => {
-                builder.insert(pat_range.end(), format!(": {}", inferred_type));
+                builder.insert(pat_range.end(), format!(": {inferred_type}"));
             }
         },
     )
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/add_return_type.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/add_return_type.rs
index f858d7a15c24..89040a8569e6 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/add_return_type.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/add_return_type.rs
@@ -35,16 +35,16 @@ pub(crate) fn add_return_type(acc: &mut Assists, ctx: &AssistContext<'_>) -> Opt
             match builder_edit_pos {
                 InsertOrReplace::Insert(insert_pos, needs_whitespace) => {
                     let preceeding_whitespace = if needs_whitespace { " " } else { "" };
-                    builder.insert(insert_pos, &format!("{}-> {} ", preceeding_whitespace, ty))
+                    builder.insert(insert_pos, &format!("{preceeding_whitespace}-> {ty} "))
                 }
                 InsertOrReplace::Replace(text_range) => {
-                    builder.replace(text_range, &format!("-> {}", ty))
+                    builder.replace(text_range, &format!("-> {ty}"))
                 }
             }
             if let FnType::Closure { wrap_expr: true } = fn_type {
                 cov_mark::hit!(wrap_closure_non_block_expr);
                 // `|x| x` becomes `|x| -> T x` which is invalid, so wrap it in a block
-                builder.replace(tail_expr.syntax().text_range(), &format!("{{{}}}", tail_expr));
+                builder.replace(tail_expr.syntax().text_range(), &format!("{{{tail_expr}}}"));
             }
         },
     )
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/add_turbo_fish.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/add_turbo_fish.rs
index c0bf238db731..acf82e4b2579 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/add_turbo_fish.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/add_turbo_fish.rs
@@ -93,12 +93,13 @@ pub(crate) fn add_turbo_fish(acc: &mut Assists, ctx: &AssistContext<'_>) -> Opti
             builder.trigger_signature_help();
             match ctx.config.snippet_cap {
                 Some(cap) => {
-                    let snip = format!("::<{}>", get_snippet_fish_head(number_of_arguments));
+                    let fish_head = get_snippet_fish_head(number_of_arguments);
+                    let snip = format!("::<{fish_head}>");
                     builder.insert_snippet(cap, ident.text_range().end(), snip)
                 }
                 None => {
                     let fish_head = std::iter::repeat("_").take(number_of_arguments).format(", ");
-                    let snip = format!("::<{}>", fish_head);
+                    let snip = format!("::<{fish_head}>");
                     builder.insert(ident.text_range().end(), snip);
                 }
             }
@@ -109,7 +110,7 @@ pub(crate) fn add_turbo_fish(acc: &mut Assists, ctx: &AssistContext<'_>) -> Opti
 /// This will create a snippet string with tabstops marked
 fn get_snippet_fish_head(number_of_arguments: usize) -> String {
     let mut fish_head = (1..number_of_arguments)
-        .format_with("", |i, f| f(&format_args!("${{{}:_}}, ", i)))
+        .format_with("", |i, f| f(&format_args!("${{{i}:_}}, ")))
         .to_string();
 
     // tabstop 0 is a special case and always the last one
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/apply_demorgan.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/apply_demorgan.rs
index 2853d1d1be3c..57cfa17cc8e1 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/apply_demorgan.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/apply_demorgan.rs
@@ -123,20 +123,20 @@ pub(crate) fn apply_demorgan(acc: &mut Assists, ctx: &AssistContext<'_>) -> Opti
                     let lhs_range = lhs.syntax().text_range();
                     let not_lhs = invert_boolean_expression(lhs);
 
-                    edit.replace(lhs_range, format!("!({}", not_lhs.syntax().text()));
+                    edit.replace(lhs_range, format!("!({not_lhs}"));
                 }
 
                 if let Some(rhs) = terms.pop_back() {
                     let rhs_range = rhs.syntax().text_range();
                     let not_rhs = invert_boolean_expression(rhs);
 
-                    edit.replace(rhs_range, format!("{})", not_rhs.syntax().text()));
+                    edit.replace(rhs_range, format!("{not_rhs})"));
                 }
 
                 for term in terms {
                     let term_range = term.syntax().text_range();
                     let not_term = invert_boolean_expression(term);
-                    edit.replace(term_range, not_term.syntax().text());
+                    edit.replace(term_range, not_term.to_string());
                 }
             }
         },
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/auto_import.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/auto_import.rs
index 678dc877d138..a689270bc091 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/auto_import.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/auto_import.rs
@@ -127,10 +127,12 @@ pub(crate) fn auto_import(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<
         .sort_by_key(|import| Reverse(relevance_score(ctx, import, current_module.as_ref())));
 
     for import in proposed_imports {
+        let import_path = import.import_path;
+
         acc.add_group(
             &group_label,
             AssistId("auto_import", AssistKind::QuickFix),
-            format!("Import `{}`", import.import_path),
+            format!("Import `{import_path}`"),
             range,
             |builder| {
                 let scope = match scope.clone() {
@@ -138,7 +140,7 @@ pub(crate) fn auto_import(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<
                     ImportScope::Module(it) => ImportScope::Module(builder.make_mut(it)),
                     ImportScope::Block(it) => ImportScope::Block(builder.make_mut(it)),
                 };
-                insert_use(&scope, mod_path_to_ast(&import.import_path), &ctx.config.insert_use);
+                insert_use(&scope, mod_path_to_ast(&import_path), &ctx.config.insert_use);
             },
         );
     }
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_comment_block.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_comment_block.rs
index f171dd81a811..312cb65abd2a 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_comment_block.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_comment_block.rs
@@ -54,16 +54,17 @@ fn block_to_line(acc: &mut Assists, comment: ast::Comment) -> Option<()> {
 
             let indent_spaces = indentation.to_string();
             let output = lines
-                .map(|l| l.trim_start_matches(&indent_spaces))
-                .map(|l| {
+                .map(|line| {
+                    let line = line.trim_start_matches(&indent_spaces);
+
                     // Don't introduce trailing whitespace
-                    if l.is_empty() {
+                    if line.is_empty() {
                         line_prefix.to_string()
                     } else {
-                        format!("{} {}", line_prefix, l.trim_start_matches(&indent_spaces))
+                        format!("{line_prefix} {line}")
                     }
                 })
-                .join(&format!("\n{}", indent_spaces));
+                .join(&format!("\n{indent_spaces}"));
 
             edit.replace(target, output)
         },
@@ -96,7 +97,7 @@ fn line_to_block(acc: &mut Assists, comment: ast::Comment) -> Option<()> {
             let block_prefix =
                 CommentKind { shape: CommentShape::Block, ..comment.kind() }.prefix();
 
-            let output = format!("{}\n{}\n{}*/", block_prefix, block_comment_body, indentation);
+            let output = format!("{block_prefix}\n{block_comment_body}\n{indentation}*/");
 
             edit.replace(target, output)
         },
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_integer_literal.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_integer_literal.rs
index 9060696cdc8e..ff2195f7e6c4 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_integer_literal.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_integer_literal.rs
@@ -32,19 +32,19 @@ pub(crate) fn convert_integer_literal(acc: &mut Assists, ctx: &AssistContext<'_>
         }
 
         let mut converted = match target_radix {
-            Radix::Binary => format!("0b{:b}", value),
-            Radix::Octal => format!("0o{:o}", value),
+            Radix::Binary => format!("0b{value:b}"),
+            Radix::Octal => format!("0o{value:o}"),
             Radix::Decimal => value.to_string(),
-            Radix::Hexadecimal => format!("0x{:X}", value),
+            Radix::Hexadecimal => format!("0x{value:X}"),
         };
 
-        let label = format!("Convert {} to {}{}", literal, converted, suffix.unwrap_or_default());
-
         // Appends the type suffix back into the new literal if it exists.
         if let Some(suffix) = suffix {
             converted.push_str(suffix);
         }
 
+        let label = format!("Convert {literal} to {converted}");
+
         acc.add_group(
             &group_id,
             AssistId("convert_integer_literal", AssistKind::RefactorInline),
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_into_to_from.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_into_to_from.rs
index 95d11abe8bc0..872b52c98fff 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_into_to_from.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_into_to_from.rs
@@ -86,9 +86,9 @@ pub(crate) fn convert_into_to_from(acc: &mut Assists, ctx: &AssistContext<'_>) -
         impl_.syntax().text_range(),
         |builder| {
             builder.replace(src_type.syntax().text_range(), dest_type.to_string());
-            builder.replace(ast_trait.syntax().text_range(), format!("From<{}>", src_type));
+            builder.replace(ast_trait.syntax().text_range(), format!("From<{src_type}>"));
             builder.replace(into_fn_return.syntax().text_range(), "-> Self");
-            builder.replace(into_fn_params.syntax().text_range(), format!("(val: {})", src_type));
+            builder.replace(into_fn_params.syntax().text_range(), format!("(val: {src_type})"));
             builder.replace(into_fn_name.syntax().text_range(), "from");
 
             for s in selfs {
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_iter_for_each_to_for.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_iter_for_each_to_for.rs
index 2cf370c09074..80eecf4a0986 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_iter_for_each_to_for.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_iter_for_each_to_for.rs
@@ -119,19 +119,19 @@ pub(crate) fn convert_for_loop_with_for_each(
             {
                 // We have either "for x in &col" and col implements a method called iter
                 //             or "for x in &mut col" and col implements a method called iter_mut
-                format_to!(buf, "{}.{}()", expr_behind_ref, method);
+                format_to!(buf, "{expr_behind_ref}.{method}()");
             } else if let ast::Expr::RangeExpr(..) = iterable {
                 // range expressions need to be parenthesized for the syntax to be correct
-                format_to!(buf, "({})", iterable);
+                format_to!(buf, "({iterable})");
             } else if impls_core_iter(&ctx.sema, &iterable) {
-                format_to!(buf, "{}", iterable);
+                format_to!(buf, "{iterable}");
             } else if let ast::Expr::RefExpr(_) = iterable {
-                format_to!(buf, "({}).into_iter()", iterable);
+                format_to!(buf, "({iterable}).into_iter()");
             } else {
-                format_to!(buf, "{}.into_iter()", iterable);
+                format_to!(buf, "{iterable}.into_iter()");
             }
 
-            format_to!(buf, ".for_each(|{}| {});", pat, body);
+            format_to!(buf, ".for_each(|{pat}| {body});");
 
             builder.replace(for_loop.syntax().text_range(), buf)
         },
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_let_else_to_match.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_let_else_to_match.rs
index 00095de257d5..c82a3b530325 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_let_else_to_match.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_let_else_to_match.rs
@@ -80,7 +80,7 @@ fn binders_to_str(binders: &[(Name, bool)], addmut: bool) -> String {
         .map(
             |(ident, ismut)| {
                 if *ismut && addmut {
-                    format!("mut {}", ident)
+                    format!("mut {ident}")
                 } else {
                     ident.to_string()
                 }
@@ -93,7 +93,7 @@ fn binders_to_str(binders: &[(Name, bool)], addmut: bool) -> String {
     } else if binders.len() == 1 {
         vars
     } else {
-        format!("({})", vars)
+        format!("({vars})")
     }
 }
 
@@ -153,7 +153,7 @@ pub(crate) fn convert_let_else_to_match(acc: &mut Assists, ctx: &AssistContext<'
 
             let only_expr = let_else_block.statements().next().is_none();
             let branch2 = match &let_else_block.tail_expr() {
-                Some(tail) if only_expr => format!("{},", tail.syntax().text()),
+                Some(tail) if only_expr => format!("{tail},"),
                 _ => let_else_block.syntax().text().to_string(),
             };
             let replace = if binders.is_empty() {
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_match_to_let_else.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_match_to_let_else.rs
new file mode 100644
index 000000000000..5bf04a3ad371
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_match_to_let_else.rs
@@ -0,0 +1,413 @@
+use ide_db::defs::{Definition, NameRefClass};
+use syntax::{
+    ast::{self, HasName},
+    ted, AstNode, SyntaxNode,
+};
+
+use crate::{
+    assist_context::{AssistContext, Assists},
+    AssistId, AssistKind,
+};
+
+// Assist: convert_match_to_let_else
+//
+// Converts let statement with match initializer to let-else statement.
+//
+// ```
+// # //- minicore: option
+// fn foo(opt: Option<()>) {
+//     let val = $0match opt {
+//         Some(it) => it,
+//         None => return,
+//     };
+// }
+// ```
+// ->
+// ```
+// fn foo(opt: Option<()>) {
+//     let Some(val) = opt else { return };
+// }
+// ```
+pub(crate) fn convert_match_to_let_else(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<()> {
+    let let_stmt: ast::LetStmt = ctx.find_node_at_offset()?;
+    let binding = find_binding(let_stmt.pat()?)?;
+
+    let initializer = match let_stmt.initializer() {
+        Some(ast::Expr::MatchExpr(it)) => it,
+        _ => return None,
+    };
+    let initializer_expr = initializer.expr()?;
+
+    let (extracting_arm, diverging_arm) = match find_arms(ctx, &initializer) {
+        Some(it) => it,
+        None => return None,
+    };
+    if extracting_arm.guard().is_some() {
+        cov_mark::hit!(extracting_arm_has_guard);
+        return None;
+    }
+
+    let diverging_arm_expr = diverging_arm.expr()?;
+    let extracting_arm_pat = extracting_arm.pat()?;
+    let extracted_variable = find_extracted_variable(ctx, &extracting_arm)?;
+
+    acc.add(
+        AssistId("convert_match_to_let_else", AssistKind::RefactorRewrite),
+        "Convert match to let-else",
+        let_stmt.syntax().text_range(),
+        |builder| {
+            let extracting_arm_pat = rename_variable(&extracting_arm_pat, extracted_variable, binding);
+            builder.replace(
+                let_stmt.syntax().text_range(),
+                format!("let {extracting_arm_pat} = {initializer_expr} else {{ {diverging_arm_expr} }};")
+            )
+        },
+    )
+}
+
+// Given a pattern, find the name introduced to the surrounding scope.
+fn find_binding(pat: ast::Pat) -> Option<ast::IdentPat> {
+    if let ast::Pat::IdentPat(ident) = pat {
+        Some(ident)
+    } else {
+        None
+    }
+}
+
+// Given a match expression, find extracting and diverging arms.
+fn find_arms(
+    ctx: &AssistContext<'_>,
+    match_expr: &ast::MatchExpr,
+) -> Option<(ast::MatchArm, ast::MatchArm)> {
+    let arms = match_expr.match_arm_list()?.arms().collect::<Vec<_>>();
+    if arms.len() != 2 {
+        return None;
+    }
+
+    let mut extracting = None;
+    let mut diverging = None;
+    for arm in arms {
+        if ctx.sema.type_of_expr(&arm.expr().unwrap()).unwrap().original().is_never() {
+            diverging = Some(arm);
+        } else {
+            extracting = Some(arm);
+        }
+    }
+
+    match (extracting, diverging) {
+        (Some(extracting), Some(diverging)) => Some((extracting, diverging)),
+        _ => {
+            cov_mark::hit!(non_diverging_match);
+            None
+        }
+    }
+}
+
+// Given an extracting arm, find the extracted variable.
+fn find_extracted_variable(ctx: &AssistContext<'_>, arm: &ast::MatchArm) -> Option<ast::Name> {
+    match arm.expr()? {
+        ast::Expr::PathExpr(path) => {
+            let name_ref = path.syntax().descendants().find_map(ast::NameRef::cast)?;
+            match NameRefClass::classify(&ctx.sema, &name_ref)? {
+                NameRefClass::Definition(Definition::Local(local)) => {
+                    let source = local.source(ctx.db()).value.left()?;
+                    Some(source.name()?)
+                }
+                _ => None,
+            }
+        }
+        _ => {
+            cov_mark::hit!(extracting_arm_is_not_an_identity_expr);
+            return None;
+        }
+    }
+}
+
+// Rename `extracted` with `binding` in `pat`.
+fn rename_variable(pat: &ast::Pat, extracted: ast::Name, binding: ast::IdentPat) -> SyntaxNode {
+    let syntax = pat.syntax().clone_for_update();
+    let extracted_syntax = syntax.covering_element(extracted.syntax().text_range());
+
+    // If `extracted` variable is a record field, we should rename it to `binding`,
+    // otherwise we just need to replace `extracted` with `binding`.
+
+    if let Some(record_pat_field) = extracted_syntax.ancestors().find_map(ast::RecordPatField::cast)
+    {
+        if let Some(name_ref) = record_pat_field.field_name() {
+            ted::replace(
+                record_pat_field.syntax(),
+                ast::make::record_pat_field(ast::make::name_ref(&name_ref.text()), binding.into())
+                    .syntax()
+                    .clone_for_update(),
+            );
+        }
+    } else {
+        ted::replace(extracted_syntax, binding.syntax().clone_for_update());
+    }
+
+    syntax
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::tests::{check_assist, check_assist_not_applicable};
+
+    use super::*;
+
+    #[test]
+    fn should_not_be_applicable_for_non_diverging_match() {
+        cov_mark::check!(non_diverging_match);
+        check_assist_not_applicable(
+            convert_match_to_let_else,
+            r#"
+//- minicore: option
+fn foo(opt: Option<()>) {
+    let val = $0match opt {
+        Some(it) => it,
+        None => (),
+    };
+}
+"#,
+        );
+    }
+
+    #[test]
+    fn should_not_be_applicable_if_extracting_arm_is_not_an_identity_expr() {
+        cov_mark::check_count!(extracting_arm_is_not_an_identity_expr, 2);
+        check_assist_not_applicable(
+            convert_match_to_let_else,
+            r#"
+//- minicore: option
+fn foo(opt: Option<i32>) {
+    let val = $0match opt {
+        Some(it) => it + 1,
+        None => return,
+    };
+}
+"#,
+        );
+
+        check_assist_not_applicable(
+            convert_match_to_let_else,
+            r#"
+//- minicore: option
+fn foo(opt: Option<()>) {
+    let val = $0match opt {
+        Some(it) => {
+            let _ = 1 + 1;
+            it
+        },
+        None => return,
+    };
+}
+"#,
+        );
+    }
+
+    #[test]
+    fn should_not_be_applicable_if_extracting_arm_has_guard() {
+        cov_mark::check!(extracting_arm_has_guard);
+        check_assist_not_applicable(
+            convert_match_to_let_else,
+            r#"
+//- minicore: option
+fn foo(opt: Option<()>) {
+    let val = $0match opt {
+        Some(it) if 2 > 1 => it,
+        None => return,
+    };
+}
+"#,
+        );
+    }
+
+    #[test]
+    fn basic_pattern() {
+        check_assist(
+            convert_match_to_let_else,
+            r#"
+//- minicore: option
+fn foo(opt: Option<()>) {
+    let val = $0match opt {
+        Some(it) => it,
+        None => return,
+    };
+}
+    "#,
+            r#"
+fn foo(opt: Option<()>) {
+    let Some(val) = opt else { return };
+}
+    "#,
+        );
+    }
+
+    #[test]
+    fn keeps_modifiers() {
+        check_assist(
+            convert_match_to_let_else,
+            r#"
+//- minicore: option
+fn foo(opt: Option<()>) {
+    let ref mut val = $0match opt {
+        Some(it) => it,
+        None => return,
+    };
+}
+    "#,
+            r#"
+fn foo(opt: Option<()>) {
+    let Some(ref mut val) = opt else { return };
+}
+    "#,
+        );
+    }
+
+    #[test]
+    fn nested_pattern() {
+        check_assist(
+            convert_match_to_let_else,
+            r#"
+//- minicore: option, result
+fn foo(opt: Option<Result<()>>) {
+    let val = $0match opt {
+        Some(Ok(it)) => it,
+        _ => return,
+    };
+}
+    "#,
+            r#"
+fn foo(opt: Option<Result<()>>) {
+    let Some(Ok(val)) = opt else { return };
+}
+    "#,
+        );
+    }
+
+    #[test]
+    fn works_with_any_diverging_block() {
+        check_assist(
+            convert_match_to_let_else,
+            r#"
+//- minicore: option
+fn foo(opt: Option<()>) {
+    loop {
+        let val = $0match opt {
+            Some(it) => it,
+            None => break,
+        };
+    }
+}
+    "#,
+            r#"
+fn foo(opt: Option<()>) {
+    loop {
+        let Some(val) = opt else { break };
+    }
+}
+    "#,
+        );
+
+        check_assist(
+            convert_match_to_let_else,
+            r#"
+//- minicore: option
+fn foo(opt: Option<()>) {
+    loop {
+        let val = $0match opt {
+            Some(it) => it,
+            None => continue,
+        };
+    }
+}
+    "#,
+            r#"
+fn foo(opt: Option<()>) {
+    loop {
+        let Some(val) = opt else { continue };
+    }
+}
+    "#,
+        );
+
+        check_assist(
+            convert_match_to_let_else,
+            r#"
+//- minicore: option
+fn panic() -> ! {}
+
+fn foo(opt: Option<()>) {
+    loop {
+        let val = $0match opt {
+            Some(it) => it,
+            None => panic(),
+        };
+    }
+}
+    "#,
+            r#"
+fn panic() -> ! {}
+
+fn foo(opt: Option<()>) {
+    loop {
+        let Some(val) = opt else { panic() };
+    }
+}
+    "#,
+        );
+    }
+
+    #[test]
+    fn struct_pattern() {
+        check_assist(
+            convert_match_to_let_else,
+            r#"
+//- minicore: option
+struct Point {
+    x: i32,
+    y: i32,
+}
+
+fn foo(opt: Option<Point>) {
+    let val = $0match opt {
+        Some(Point { x: 0, y }) => y,
+        _ => return,
+    };
+}
+    "#,
+            r#"
+struct Point {
+    x: i32,
+    y: i32,
+}
+
+fn foo(opt: Option<Point>) {
+    let Some(Point { x: 0, y: val }) = opt else { return };
+}
+    "#,
+        );
+    }
+
+    #[test]
+    fn renames_whole_binding() {
+        check_assist(
+            convert_match_to_let_else,
+            r#"
+//- minicore: option
+fn foo(opt: Option<i32>) -> Option<i32> {
+    let val = $0match opt {
+        it @ Some(42) => it,
+        _ => return None,
+    };
+    val
+}
+    "#,
+            r#"
+fn foo(opt: Option<i32>) -> Option<i32> {
+    let val @ Some(42) = opt else { return None };
+    val
+}
+    "#,
+        );
+    }
+}
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_to_guarded_return.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_to_guarded_return.rs
index cb75619ced9c..b97be34c5f7e 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_to_guarded_return.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_to_guarded_return.rs
@@ -129,32 +129,15 @@ pub(crate) fn convert_to_guarded_return(acc: &mut Assists, ctx: &AssistContext<'
                 }
                 Some((path, bound_ident)) => {
                     // If-let.
-                    let match_expr = {
-                        let happy_arm = {
-                            let pat = make::tuple_struct_pat(
-                                path,
-                                once(make::ext::simple_ident_pat(make::name("it")).into()),
-                            );
-                            let expr = {
-                                let path = make::ext::ident_path("it");
-                                make::expr_path(path)
-                            };
-                            make::match_arm(once(pat.into()), None, expr)
-                        };
-
-                        let sad_arm = make::match_arm(
-                            // FIXME: would be cool to use `None` or `Err(_)` if appropriate
-                            once(make::wildcard_pat().into()),
-                            None,
-                            early_expression,
-                        );
-
-                        make::expr_match(cond_expr, make::match_arm_list(vec![happy_arm, sad_arm]))
-                    };
-
-                    let let_stmt = make::let_stmt(bound_ident, None, Some(match_expr));
-                    let let_stmt = let_stmt.indent(if_indent_level);
-                    let_stmt.syntax().clone_for_update()
+                    let pat = make::tuple_struct_pat(path, once(bound_ident));
+                    let let_else_stmt = make::let_else_stmt(
+                        pat.into(),
+                        None,
+                        cond_expr,
+                        ast::make::tail_only_block_expr(early_expression),
+                    );
+                    let let_else_stmt = let_else_stmt.indent(if_indent_level);
+                    let_else_stmt.syntax().clone_for_update()
                 }
             };
 
@@ -238,10 +221,7 @@ fn main(n: Option<String>) {
             r#"
 fn main(n: Option<String>) {
     bar();
-    let n = match n {
-        Some(it) => it,
-        _ => return,
-    };
+    let Some(n) = n else { return };
     foo(n);
 
     // comment
@@ -264,10 +244,7 @@ fn main() {
 "#,
             r#"
 fn main() {
-    let x = match Err(92) {
-        Ok(it) => it,
-        _ => return,
-    };
+    let Ok(x) = Err(92) else { return };
     foo(x);
 }
 "#,
@@ -292,10 +269,7 @@ fn main(n: Option<String>) {
             r#"
 fn main(n: Option<String>) {
     bar();
-    let n = match n {
-        Some(it) => it,
-        _ => return,
-    };
+    let Some(n) = n else { return };
     foo(n);
 
     // comment
@@ -323,10 +297,7 @@ fn main(n: Option<String>) {
             r#"
 fn main(n: Option<String>) {
     bar();
-    let mut n = match n {
-        Some(it) => it,
-        _ => return,
-    };
+    let Some(mut n) = n else { return };
     foo(n);
 
     // comment
@@ -354,10 +325,7 @@ fn main(n: Option<&str>) {
             r#"
 fn main(n: Option<&str>) {
     bar();
-    let ref n = match n {
-        Some(it) => it,
-        _ => return,
-    };
+    let Some(ref n) = n else { return };
     foo(n);
 
     // comment
@@ -412,10 +380,7 @@ fn main() {
             r#"
 fn main() {
     while true {
-        let n = match n {
-            Some(it) => it,
-            _ => continue,
-        };
+        let Some(n) = n else { continue };
         foo(n);
         bar();
     }
@@ -469,10 +434,7 @@ fn main() {
             r#"
 fn main() {
     loop {
-        let n = match n {
-            Some(it) => it,
-            _ => continue,
-        };
+        let Some(n) = n else { continue };
         foo(n);
         bar();
     }
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_tuple_struct_to_named_struct.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_tuple_struct_to_named_struct.rs
index d8f522708460..92e091fca126 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_tuple_struct_to_named_struct.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_tuple_struct_to_named_struct.rs
@@ -226,7 +226,13 @@ fn edit_field_references(
 }
 
 fn generate_names(fields: impl Iterator<Item = ast::TupleField>) -> Vec<ast::Name> {
-    fields.enumerate().map(|(i, _)| ast::make::name(&format!("field{}", i + 1))).collect()
+    fields
+        .enumerate()
+        .map(|(i, _)| {
+            let idx = i + 1;
+            ast::make::name(&format!("field{idx}"))
+        })
+        .collect()
 }
 
 #[cfg(test)]
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_two_arm_bool_match_to_matches_macro.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_two_arm_bool_match_to_matches_macro.rs
index 54a7f480a4e4..b1b0f587cd33 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_two_arm_bool_match_to_matches_macro.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_two_arm_bool_match_to_matches_macro.rs
@@ -58,16 +58,16 @@ pub(crate) fn convert_two_arm_bool_match_to_matches_macro(
         target_range,
         |builder| {
             let mut arm_str = String::new();
-            if let Some(ref pat) = first_arm.pat() {
+            if let Some(pat) = &first_arm.pat() {
                 arm_str += &pat.to_string();
             }
-            if let Some(ref guard) = first_arm.guard() {
-                arm_str += &format!(" {}", &guard.to_string());
+            if let Some(guard) = &first_arm.guard() {
+                arm_str += &format!(" {guard}");
             }
             if invert_matches {
-                builder.replace(target_range, format!("!matches!({}, {})", expr, arm_str));
+                builder.replace(target_range, format!("!matches!({expr}, {arm_str})"));
             } else {
-                builder.replace(target_range, format!("matches!({}, {})", expr, arm_str));
+                builder.replace(target_range, format!("matches!({expr}, {arm_str})"));
             }
         },
     )
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/destructure_tuple_binding.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/destructure_tuple_binding.rs
index dc581ff3bd2c..31c2ce7c1b54 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/destructure_tuple_binding.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/destructure_tuple_binding.rs
@@ -133,7 +133,7 @@ fn generate_name(
     _usages: &Option<UsageSearchResult>,
 ) -> String {
     // FIXME: detect if name already used
-    format!("_{}", index)
+    format!("_{index}")
 }
 
 enum RefType {
@@ -168,12 +168,12 @@ fn edit_tuple_assignment(
     let add_cursor = |text: &str| {
         // place cursor on first tuple item
         let first_tuple = &data.field_names[0];
-        text.replacen(first_tuple, &format!("$0{}", first_tuple), 1)
+        text.replacen(first_tuple, &format!("$0{first_tuple}"), 1)
     };
 
     // with sub_pattern: keep original tuple and add subpattern: `tup @ (_0, _1)`
     if in_sub_pattern {
-        let text = format!(" @ {}", tuple_pat);
+        let text = format!(" @ {tuple_pat}");
         match ctx.config.snippet_cap {
             Some(cap) => {
                 let snip = add_cursor(&text);
@@ -314,9 +314,9 @@ struct RefData {
 impl RefData {
     fn format(&self, field_name: &str) -> String {
         match (self.needs_deref, self.needs_parentheses) {
-            (true, true) => format!("(*{})", field_name),
-            (true, false) => format!("*{}", field_name),
-            (false, true) => format!("({})", field_name),
+            (true, true) => format!("(*{field_name})"),
+            (true, false) => format!("*{field_name}"),
+            (false, true) => format!("({field_name})"),
             (false, false) => field_name.to_string(),
         }
     }
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_function.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_function.rs
index d6c8ea785f84..060588358492 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_function.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_function.rs
@@ -181,7 +181,7 @@ fn make_function_name(semantics_scope: &hir::SemanticsScope<'_>) -> ast::NameRef
     let mut counter = 0;
     while names_in_scope.contains(&name) {
         counter += 1;
-        name = format!("{}{}", &default_name, counter)
+        name = format!("{default_name}{counter}")
     }
     make::name_ref(&name)
 }
@@ -1291,19 +1291,23 @@ fn make_call(ctx: &AssistContext<'_>, fun: &Function, indent: IndentLevel) -> St
     match fun.outliving_locals.as_slice() {
         [] => {}
         [var] => {
-            format_to!(buf, "let {}{} = ", mut_modifier(var), var.local.name(ctx.db()))
+            let modifier = mut_modifier(var);
+            let name = var.local.name(ctx.db());
+            format_to!(buf, "let {modifier}{name} = ")
         }
         vars => {
             buf.push_str("let (");
             let bindings = vars.iter().format_with(", ", |local, f| {
-                f(&format_args!("{}{}", mut_modifier(local), local.local.name(ctx.db())))
+                let modifier = mut_modifier(local);
+                let name = local.local.name(ctx.db());
+                f(&format_args!("{modifier}{name}"))
             });
-            format_to!(buf, "{}", bindings);
+            format_to!(buf, "{bindings}");
             buf.push_str(") = ");
         }
     }
 
-    format_to!(buf, "{}", expr);
+    format_to!(buf, "{expr}");
     let insert_comma = fun
         .body
         .parent()
@@ -1447,6 +1451,8 @@ fn format_function(
     new_indent: IndentLevel,
 ) -> String {
     let mut fn_def = String::new();
+
+    let fun_name = &fun.name;
     let params = fun.make_param_list(ctx, module);
     let ret_ty = fun.make_ret_ty(ctx, module);
     let body = make_body(ctx, old_indent, new_indent, fun);
@@ -1454,42 +1460,28 @@ fn format_function(
     let async_kw = if fun.control_flow.is_async { "async " } else { "" };
     let unsafe_kw = if fun.control_flow.is_unsafe { "unsafe " } else { "" };
     let (generic_params, where_clause) = make_generic_params_and_where_clause(ctx, fun);
+
+    format_to!(fn_def, "\n\n{new_indent}{const_kw}{async_kw}{unsafe_kw}");
     match ctx.config.snippet_cap {
-        Some(_) => format_to!(
-            fn_def,
-            "\n\n{}{}{}{}fn $0{}",
-            new_indent,
-            const_kw,
-            async_kw,
-            unsafe_kw,
-            fun.name,
-        ),
-        None => format_to!(
-            fn_def,
-            "\n\n{}{}{}{}fn {}",
-            new_indent,
-            const_kw,
-            async_kw,
-            unsafe_kw,
-            fun.name,
-        ),
+        Some(_) => format_to!(fn_def, "fn $0{fun_name}"),
+        None => format_to!(fn_def, "fn {fun_name}"),
     }
 
     if let Some(generic_params) = generic_params {
-        format_to!(fn_def, "{}", generic_params);
+        format_to!(fn_def, "{generic_params}");
     }
 
-    format_to!(fn_def, "{}", params);
+    format_to!(fn_def, "{params}");
 
     if let Some(ret_ty) = ret_ty {
-        format_to!(fn_def, " {}", ret_ty);
+        format_to!(fn_def, " {ret_ty}");
     }
 
     if let Some(where_clause) = where_clause {
-        format_to!(fn_def, " {}", where_clause);
+        format_to!(fn_def, " {where_clause}");
     }
 
-    format_to!(fn_def, " {}", body);
+    format_to!(fn_def, " {body}");
 
     fn_def
 }
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_module.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_module.rs
index 897980c66504..56834394aeba 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_module.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_module.rs
@@ -127,7 +127,7 @@ pub(crate) fn extract_module(acc: &mut Assists, ctx: &AssistContext<'_>) -> Opti
             for item in items_to_be_processed {
                 let item = item.indent(IndentLevel(1));
                 let mut indented_item = String::new();
-                format_to!(indented_item, "{}{}", new_item_indent, item.to_string());
+                format_to!(indented_item, "{new_item_indent}{item}");
                 body_items.push(indented_item);
             }
 
@@ -137,30 +137,28 @@ pub(crate) fn extract_module(acc: &mut Assists, ctx: &AssistContext<'_>) -> Opti
                 let mut impl_body_def = String::new();
 
                 if let Some(self_ty) = impl_.self_ty() {
-                    format_to!(
-                        impl_body_def,
-                        "{}impl {} {{\n{}\n{}}}",
-                        old_item_indent + 1,
-                        self_ty.to_string(),
-                        body,
-                        old_item_indent + 1
-                    );
-
+                    {
+                        let impl_indent = old_item_indent + 1;
+                        format_to!(
+                            impl_body_def,
+                            "{impl_indent}impl {self_ty} {{\n{body}\n{impl_indent}}}",
+                        );
+                    }
                     body = impl_body_def;
 
                     // Add the import for enum/struct corresponding to given impl block
                     module.make_use_stmt_of_node_with_super(self_ty.syntax());
                     for item in module.use_items {
-                        let mut indented_item = String::new();
-                        format_to!(indented_item, "{}{}", old_item_indent + 1, item.to_string());
-                        body = format!("{}\n\n{}", indented_item, body);
+                        let item_indent = old_item_indent + 1;
+                        body = format!("{item_indent}{item}\n\n{body}");
                     }
                 }
             }
 
             let mut module_def = String::new();
 
-            format_to!(module_def, "mod {} {{\n{}\n{}}}", module.name, body, old_item_indent);
+            let module_name = module.name;
+            format_to!(module_def, "mod {module_name} {{\n{body}\n{old_item_indent}}}");
 
             let mut usages_to_be_updated_for_curr_file = vec![];
             for usages_to_be_updated_for_file in usages_to_be_processed {
@@ -199,7 +197,7 @@ pub(crate) fn extract_module(acc: &mut Assists, ctx: &AssistContext<'_>) -> Opti
                     builder.delete(range);
                 }
 
-                builder.insert(impl_.syntax().text_range().end(), format!("\n\n{}", module_def));
+                builder.insert(impl_.syntax().text_range().end(), format!("\n\n{module_def}"));
             } else {
                 builder.replace(module.text_range, module_def)
             }
@@ -343,9 +341,10 @@ impl Module {
                 && !self.text_range.contains_range(desc.text_range())
             {
                 if let Some(name_ref) = ast::NameRef::cast(desc) {
+                    let mod_name = self.name;
                     return Some((
                         name_ref.syntax().text_range(),
-                        format!("{}::{}", self.name, name_ref),
+                        format!("{mod_name}::{name_ref}"),
                     ));
                 }
             }
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_struct_from_enum_variant.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_struct_from_enum_variant.rs
index 970e948dfd93..b4e10667b07a 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_struct_from_enum_variant.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_struct_from_enum_variant.rs
@@ -296,10 +296,14 @@ fn create_struct_def(
 
 fn update_variant(variant: &ast::Variant, generics: Option<ast::GenericParamList>) -> Option<()> {
     let name = variant.name()?;
-    let ty = generics
+    let generic_args = generics
         .filter(|generics| generics.generic_params().count() > 0)
-        .map(|generics| make::ty(&format!("{}{}", &name.text(), generics.to_generic_args())))
-        .unwrap_or_else(|| make::ty(&name.text()));
+        .map(|generics| generics.to_generic_args());
+    // FIXME: replace with a `ast::make` constructor
+    let ty = match generic_args {
+        Some(generic_args) => make::ty(&format!("{name}{generic_args}")),
+        None => make::ty(&name.text()),
+    };
 
     // change from a record to a tuple field list
     let tuple_field = make::tuple_field(None, ty);
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_type_alias.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_type_alias.rs
index 03aa8601d14e..3116935fc5e7 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_type_alias.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_type_alias.rs
@@ -1,8 +1,7 @@
 use either::Either;
 use ide_db::syntax_helpers::node_ext::walk_ty;
-use itertools::Itertools;
 use syntax::{
-    ast::{self, edit::IndentLevel, AstNode, HasGenericParams, HasName},
+    ast::{self, edit::IndentLevel, make, AstNode, HasGenericParams, HasName},
     match_ast,
 };
 
@@ -64,41 +63,29 @@ pub(crate) fn extract_type_alias(acc: &mut Assists, ctx: &AssistContext<'_>) ->
                 known_generics.extend(it.generic_params());
             }
             let generics = collect_used_generics(&ty, &known_generics);
+            let generic_params =
+                generics.map(|it| make::generic_param_list(it.into_iter().cloned()));
 
-            let replacement = if !generics.is_empty() {
-                format!(
-                    "Type<{}>",
-                    generics.iter().format_with(", ", |generic, f| {
-                        match generic {
-                            ast::GenericParam::ConstParam(cp) => f(&cp.name().unwrap()),
-                            ast::GenericParam::LifetimeParam(lp) => f(&lp.lifetime().unwrap()),
-                            ast::GenericParam::TypeParam(tp) => f(&tp.name().unwrap()),
-                        }
-                    })
-                )
-            } else {
-                String::from("Type")
-            };
+            let ty_args = generic_params
+                .as_ref()
+                .map_or(String::new(), |it| it.to_generic_args().to_string());
+            let replacement = format!("Type{ty_args}");
             builder.replace(target, replacement);
 
             let indent = IndentLevel::from_node(node);
-            let generics = if !generics.is_empty() {
-                format!("<{}>", generics.iter().format(", "))
-            } else {
-                String::new()
-            };
+            let generic_params = generic_params.map_or(String::new(), |it| it.to_string());
             match ctx.config.snippet_cap {
                 Some(cap) => {
                     builder.insert_snippet(
                         cap,
                         insert_pos,
-                        format!("type $0Type{} = {};\n\n{}", generics, ty, indent),
+                        format!("type $0Type{generic_params} = {ty};\n\n{indent}"),
                     );
                 }
                 None => {
                     builder.insert(
                         insert_pos,
-                        format!("type Type{} = {};\n\n{}", generics, ty, indent),
+                        format!("type Type{generic_params} = {ty};\n\n{indent}"),
                     );
                 }
             }
@@ -109,7 +96,7 @@ pub(crate) fn extract_type_alias(acc: &mut Assists, ctx: &AssistContext<'_>) ->
 fn collect_used_generics<'gp>(
     ty: &ast::Type,
     known_generics: &'gp [ast::GenericParam],
-) -> Vec<&'gp ast::GenericParam> {
+) -> Option<Vec<&'gp ast::GenericParam>> {
     // can't use a closure -> closure here cause lifetime inference fails for that
     fn find_lifetime(text: &str) -> impl Fn(&&ast::GenericParam) -> bool + '_ {
         move |gp: &&ast::GenericParam| match gp {
@@ -198,7 +185,8 @@ fn collect_used_generics<'gp>(
         ast::GenericParam::LifetimeParam(_) => 0,
         ast::GenericParam::TypeParam(_) => 1,
     });
-    generics
+
+    Some(generics).filter(|it| it.len() > 0)
 }
 
 #[cfg(test)]
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_variable.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_variable.rs
index 3596b6f82381..a738deffb95b 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_variable.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_variable.rs
@@ -91,13 +91,13 @@ pub(crate) fn extract_variable(acc: &mut Assists, ctx: &AssistContext<'_>) -> Op
 
             match anchor {
                 Anchor::Before(_) | Anchor::Replace(_) => {
-                    format_to!(buf, "let {}{} = {}", var_modifier, var_name, reference_modifier)
+                    format_to!(buf, "let {var_modifier}{var_name} = {reference_modifier}")
                 }
                 Anchor::WrapInBlock(_) => {
-                    format_to!(buf, "{{ let {} = {}", var_name, reference_modifier)
+                    format_to!(buf, "{{ let {var_name} = {reference_modifier}")
                 }
             };
-            format_to!(buf, "{}", to_extract.syntax());
+            format_to!(buf, "{to_extract}");
 
             if let Anchor::Replace(stmt) = anchor {
                 cov_mark::hit!(test_extract_var_expr_stmt);
@@ -107,8 +107,8 @@ pub(crate) fn extract_variable(acc: &mut Assists, ctx: &AssistContext<'_>) -> Op
                 match ctx.config.snippet_cap {
                     Some(cap) => {
                         let snip = buf.replace(
-                            &format!("let {}{}", var_modifier, var_name),
-                            &format!("let {}$0{}", var_modifier, var_name),
+                            &format!("let {var_modifier}{var_name}"),
+                            &format!("let {var_modifier}$0{var_name}"),
                         );
                         edit.replace_snippet(cap, expr_range, snip)
                     }
@@ -135,8 +135,8 @@ pub(crate) fn extract_variable(acc: &mut Assists, ctx: &AssistContext<'_>) -> Op
             match ctx.config.snippet_cap {
                 Some(cap) => {
                     let snip = buf.replace(
-                        &format!("let {}{}", var_modifier, var_name),
-                        &format!("let {}$0{}", var_modifier, var_name),
+                        &format!("let {var_modifier}{var_name}"),
+                        &format!("let {var_modifier}$0{var_name}"),
                     );
                     edit.insert_snippet(cap, offset, snip)
                 }
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/fix_visibility.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/fix_visibility.rs
index b33846f54665..876454302870 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/fix_visibility.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/fix_visibility.rs
@@ -57,8 +57,8 @@ fn add_vis_to_referenced_module_def(acc: &mut Assists, ctx: &AssistContext<'_>)
         if current_module.krate() == target_module.krate() { "pub(crate)" } else { "pub" };
 
     let assist_label = match target_name {
-        None => format!("Change visibility to {}", missing_visibility),
-        Some(name) => format!("Change visibility of {} to {}", name, missing_visibility),
+        None => format!("Change visibility to {missing_visibility}"),
+        Some(name) => format!("Change visibility of {name} to {missing_visibility}"),
     };
 
     acc.add(AssistId("fix_visibility", AssistKind::QuickFix), assist_label, target, |builder| {
@@ -68,15 +68,15 @@ fn add_vis_to_referenced_module_def(acc: &mut Assists, ctx: &AssistContext<'_>)
                 Some(current_visibility) => builder.replace_snippet(
                     cap,
                     current_visibility.syntax().text_range(),
-                    format!("$0{}", missing_visibility),
+                    format!("$0{missing_visibility}"),
                 ),
-                None => builder.insert_snippet(cap, offset, format!("$0{} ", missing_visibility)),
+                None => builder.insert_snippet(cap, offset, format!("$0{missing_visibility} ")),
             },
             None => match current_visibility {
                 Some(current_visibility) => {
                     builder.replace(current_visibility.syntax().text_range(), missing_visibility)
                 }
-                None => builder.insert(offset, format!("{} ", missing_visibility)),
+                None => builder.insert(offset, format!("{missing_visibility} ")),
             },
         }
     })
@@ -114,7 +114,7 @@ fn add_vis_to_referenced_record_field(acc: &mut Assists, ctx: &AssistContext<'_>
 
     let target_name = record_field_def.name(ctx.db());
     let assist_label =
-        format!("Change visibility of {}.{} to {}", parent_name, target_name, missing_visibility);
+        format!("Change visibility of {parent_name}.{target_name} to {missing_visibility}");
 
     acc.add(AssistId("fix_visibility", AssistKind::QuickFix), assist_label, target, |builder| {
         builder.edit_file(target_file);
@@ -123,15 +123,15 @@ fn add_vis_to_referenced_record_field(acc: &mut Assists, ctx: &AssistContext<'_>
                 Some(current_visibility) => builder.replace_snippet(
                     cap,
                     current_visibility.syntax().text_range(),
-                    format!("$0{}", missing_visibility),
+                    format!("$0{missing_visibility}"),
                 ),
-                None => builder.insert_snippet(cap, offset, format!("$0{} ", missing_visibility)),
+                None => builder.insert_snippet(cap, offset, format!("$0{missing_visibility} ")),
             },
             None => match current_visibility {
                 Some(current_visibility) => {
                     builder.replace(current_visibility.syntax().text_range(), missing_visibility)
                 }
-                None => builder.insert(offset, format!("{} ", missing_visibility)),
+                None => builder.insert(offset, format!("{missing_visibility} ")),
             },
         }
     })
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_constant.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_constant.rs
index eaa6de73eb35..ccdfcb0d9e4f 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_constant.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_constant.rs
@@ -77,7 +77,7 @@ pub(crate) fn generate_constant(acc: &mut Assists, ctx: &AssistContext<'_>) -> O
         target_data_for_generate_constant(ctx, current_module, constant_module).unwrap_or_else(
             || {
                 let indent = IndentLevel::from_node(statement.syntax());
-                (statement.syntax().text_range().start(), indent, None, format!("\n{}", indent))
+                (statement.syntax().text_range().start(), indent, None, format!("\n{indent}"))
             },
         );
 
@@ -90,7 +90,7 @@ pub(crate) fn generate_constant(acc: &mut Assists, ctx: &AssistContext<'_>) -> O
             if let Some(file_id) = file_id {
                 builder.edit_file(file_id);
             }
-            builder.insert(offset, format!("{}{}", text, post_string));
+            builder.insert(offset, format!("{text}{post_string}"));
         },
     )
 }
@@ -103,13 +103,13 @@ fn get_text_for_generate_constant(
 ) -> Option<String> {
     let constant_token = not_exist_name_ref.pop()?;
     let vis = if not_exist_name_ref.len() == 0 && !outer_exists { "" } else { "\npub " };
-    let mut text = format!("{}const {}: {} = $0;", vis, constant_token, type_name);
+    let mut text = format!("{vis}const {constant_token}: {type_name} = $0;");
     while let Some(name_ref) = not_exist_name_ref.pop() {
         let vis = if not_exist_name_ref.len() == 0 && !outer_exists { "" } else { "\npub " };
         text = text.replace("\n", "\n    ");
-        text = format!("{}mod {} {{{}\n}}", vis, name_ref.to_string(), text);
+        text = format!("{vis}mod {name_ref} {{{text}\n}}");
     }
-    Some(text.replace("\n", &format!("\n{}", indent)))
+    Some(text.replace("\n", &format!("\n{indent}")))
 }
 
 fn target_data_for_generate_constant(
@@ -134,7 +134,7 @@ fn target_data_for_generate_constant(
                 .find(|it| it.kind() == SyntaxKind::WHITESPACE && it.to_string().contains("\n"))
                 .is_some();
             let post_string =
-                if siblings_has_newline { format!("{}", indent) } else { format!("\n{}", indent) };
+                if siblings_has_newline { format!("{indent}") } else { format!("\n{indent}") };
             Some((offset, indent + 1, Some(file_id), post_string))
         }
         _ => Some((TextSize::from(0), 0.into(), Some(file_id), "\n".into())),
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_default_from_enum_variant.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_default_from_enum_variant.rs
index 5e9995a98664..a6e3d49e0d1a 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_default_from_enum_variant.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_default_from_enum_variant.rs
@@ -55,12 +55,11 @@ pub(crate) fn generate_default_from_enum_variant(
             let buf = format!(
                 r#"
 
-impl Default for {0} {{
+impl Default for {enum_name} {{
     fn default() -> Self {{
-        Self::{1}
+        Self::{variant_name}
     }}
 }}"#,
-                enum_name, variant_name
             );
             edit.insert(start_offset, buf);
         },
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_default_from_new.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_default_from_new.rs
index cbd33de19eda..49d9fd707ffc 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_default_from_new.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_default_from_new.rs
@@ -1,8 +1,7 @@
 use ide_db::famous_defs::FamousDefs;
-use itertools::Itertools;
 use stdx::format_to;
 use syntax::{
-    ast::{self, HasGenericParams, HasName, HasTypeBounds, Impl},
+    ast::{self, make, HasGenericParams, HasName, Impl},
     AstNode,
 };
 
@@ -77,45 +76,47 @@ pub(crate) fn generate_default_from_new(acc: &mut Assists, ctx: &AssistContext<'
     )
 }
 
+// FIXME: based on from utils::generate_impl_text_inner
 fn generate_trait_impl_text_from_impl(impl_: &ast::Impl, trait_text: &str, code: &str) -> String {
-    let generic_params = impl_.generic_param_list();
+    let impl_ty = impl_.self_ty().unwrap();
+    let generic_params = impl_.generic_param_list().map(|generic_params| {
+        let lifetime_params =
+            generic_params.lifetime_params().map(ast::GenericParam::LifetimeParam);
+        let ty_or_const_params = generic_params.type_or_const_params().filter_map(|param| {
+            // remove defaults since they can't be specified in impls
+            match param {
+                ast::TypeOrConstParam::Type(param) => {
+                    let param = param.clone_for_update();
+                    param.remove_default();
+                    Some(ast::GenericParam::TypeParam(param))
+                }
+                ast::TypeOrConstParam::Const(param) => {
+                    let param = param.clone_for_update();
+                    param.remove_default();
+                    Some(ast::GenericParam::ConstParam(param))
+                }
+            }
+        });
+
+        make::generic_param_list(itertools::chain(lifetime_params, ty_or_const_params))
+    });
+
     let mut buf = String::with_capacity(code.len());
     buf.push_str("\n\n");
+
+    // `impl{generic_params} {trait_text} for {impl_.self_ty()}`
     buf.push_str("impl");
-
     if let Some(generic_params) = &generic_params {
-        let lifetimes = generic_params.lifetime_params().map(|lt| format!("{}", lt.syntax()));
-        let toc_params = generic_params.type_or_const_params().map(|toc_param| match toc_param {
-            ast::TypeOrConstParam::Type(type_param) => {
-                let mut buf = String::new();
-                if let Some(it) = type_param.name() {
-                    format_to!(buf, "{}", it.syntax());
-                }
-                if let Some(it) = type_param.colon_token() {
-                    format_to!(buf, "{} ", it);
-                }
-                if let Some(it) = type_param.type_bound_list() {
-                    format_to!(buf, "{}", it.syntax());
-                }
-                buf
-            }
-            ast::TypeOrConstParam::Const(const_param) => const_param.syntax().to_string(),
-        });
-        let generics = lifetimes.chain(toc_params).format(", ");
-        format_to!(buf, "<{}>", generics);
+        format_to!(buf, "{generic_params}")
     }
-
-    buf.push(' ');
-    buf.push_str(trait_text);
-    buf.push_str(" for ");
-    buf.push_str(&impl_.self_ty().unwrap().syntax().text().to_string());
+    format_to!(buf, " {trait_text} for {impl_ty}");
 
     match impl_.where_clause() {
         Some(where_clause) => {
-            format_to!(buf, "\n{}\n{{\n{}\n}}", where_clause, code);
+            format_to!(buf, "\n{where_clause}\n{{\n{code}\n}}");
         }
         None => {
-            format_to!(buf, " {{\n{}\n}}", code);
+            format_to!(buf, " {{\n{code}\n}}");
         }
     }
 
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_delegate_methods.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_delegate_methods.rs
index 85b193663a05..ceae80755037 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_delegate_methods.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_delegate_methods.rs
@@ -51,14 +51,14 @@ pub(crate) fn generate_delegate_methods(acc: &mut Assists, ctx: &AssistContext<'
         Some(field) => {
             let field_name = field.name()?;
             let field_ty = field.ty()?;
-            (format!("{}", field_name), field_ty, field.syntax().text_range())
+            (field_name.to_string(), field_ty, field.syntax().text_range())
         }
         None => {
             let field = ctx.find_node_at_offset::<ast::TupleField>()?;
             let field_list = ctx.find_node_at_offset::<ast::TupleFieldList>()?;
             let field_list_index = field_list.fields().position(|it| it == field)?;
             let field_ty = field.ty()?;
-            (format!("{}", field_list_index), field_ty, field.syntax().text_range())
+            (field_list_index.to_string(), field_ty, field.syntax().text_range())
         }
     };
 
@@ -77,7 +77,7 @@ pub(crate) fn generate_delegate_methods(acc: &mut Assists, ctx: &AssistContext<'
     for method in methods {
         let adt = ast::Adt::Struct(strukt.clone());
         let name = method.name(ctx.db()).to_string();
-        let impl_def = find_struct_impl(ctx, &adt, &name).flatten();
+        let impl_def = find_struct_impl(ctx, &adt, &[name]).flatten();
         acc.add_group(
             &GroupLabel("Generate delegate methods…".to_owned()),
             AssistId("generate_delegate_methods", AssistKind::Generate),
@@ -151,7 +151,7 @@ pub(crate) fn generate_delegate_methods(acc: &mut Assists, ctx: &AssistContext<'
                             Some(cap) => {
                                 let offset = strukt.syntax().text_range().end();
                                 let snippet = render_snippet(cap, impl_def.syntax(), cursor);
-                                let snippet = format!("\n\n{}", snippet);
+                                let snippet = format!("\n\n{snippet}");
                                 builder.insert_snippet(cap, offset, snippet);
                             }
                             None => {
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_deref.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_deref.rs
index 8f4405a8c869..55b7afb3d3b0 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_deref.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_deref.rs
@@ -66,7 +66,7 @@ fn generate_record_deref(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<(
     let target = field.syntax().text_range();
     acc.add(
         AssistId("generate_deref", AssistKind::Generate),
-        format!("Generate `{:?}` impl using `{}`", deref_type_to_generate, field_name),
+        format!("Generate `{deref_type_to_generate:?}` impl using `{field_name}`"),
         target,
         |edit| {
             generate_edit(
@@ -106,7 +106,7 @@ fn generate_tuple_deref(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<()
     let target = field.syntax().text_range();
     acc.add(
         AssistId("generate_deref", AssistKind::Generate),
-        format!("Generate `{:?}` impl using `{}`", deref_type_to_generate, field.syntax()),
+        format!("Generate `{deref_type_to_generate:?}` impl using `{field}`"),
         target,
         |edit| {
             generate_edit(
@@ -132,18 +132,16 @@ fn generate_edit(
     let start_offset = strukt.syntax().text_range().end();
     let impl_code = match deref_type {
         DerefType::Deref => format!(
-            r#"    type Target = {0};
+            r#"    type Target = {field_type_syntax};
 
     fn deref(&self) -> &Self::Target {{
-        &self.{1}
+        &self.{field_name}
     }}"#,
-            field_type_syntax, field_name
         ),
         DerefType::DerefMut => format!(
             r#"    fn deref_mut(&mut self) -> &mut Self::Target {{
-        &mut self.{}
+        &mut self.{field_name}
     }}"#,
-            field_name
         ),
     };
     let strukt_adt = ast::Adt::Struct(strukt);
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_documentation_template.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_documentation_template.rs
index c91141f8eb50..b8415c72a2a3 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_documentation_template.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_documentation_template.rs
@@ -139,40 +139,44 @@ fn make_example_for_fn(ast_func: &ast::Fn, ctx: &AssistContext<'_>) -> Option<St
 
     let mut example = String::new();
 
+    let use_path = build_path(ast_func, ctx)?;
     let is_unsafe = ast_func.unsafe_token().is_some();
     let param_list = ast_func.param_list()?;
     let ref_mut_params = ref_mut_params(&param_list);
     let self_name = self_name(ast_func);
 
-    format_to!(example, "use {};\n\n", build_path(ast_func, ctx)?);
+    format_to!(example, "use {use_path};\n\n");
     if let Some(self_name) = &self_name {
-        if let Some(mtbl) = is_ref_mut_self(ast_func) {
-            let mtbl = if mtbl == true { " mut" } else { "" };
-            format_to!(example, "let{} {} = ;\n", mtbl, self_name);
+        if let Some(mut_) = is_ref_mut_self(ast_func) {
+            let mut_ = if mut_ == true { "mut " } else { "" };
+            format_to!(example, "let {mut_}{self_name} = ;\n");
         }
     }
     for param_name in &ref_mut_params {
-        format_to!(example, "let mut {} = ;\n", param_name);
+        format_to!(example, "let mut {param_name} = ;\n");
     }
     // Call the function, check result
     let function_call = function_call(ast_func, &param_list, self_name.as_deref(), is_unsafe)?;
     if returns_a_value(ast_func, ctx) {
         if count_parameters(&param_list) < 3 {
-            format_to!(example, "assert_eq!({}, );\n", function_call);
+            format_to!(example, "assert_eq!({function_call}, );\n");
         } else {
-            format_to!(example, "let result = {};\n", function_call);
+            format_to!(example, "let result = {function_call};\n");
             example.push_str("assert_eq!(result, );\n");
         }
     } else {
-        format_to!(example, "{};\n", function_call);
+        format_to!(example, "{function_call};\n");
     }
     // Check the mutated values
-    if is_ref_mut_self(ast_func) == Some(true) {
-        format_to!(example, "assert_eq!({}, );", self_name?);
+    if let Some(self_name) = &self_name {
+        if is_ref_mut_self(ast_func) == Some(true) {
+            format_to!(example, "assert_eq!({self_name}, );");
+        }
     }
     for param_name in &ref_mut_params {
-        format_to!(example, "assert_eq!({}, );", param_name);
+        format_to!(example, "assert_eq!({param_name}, );");
     }
+
     Some(example)
 }
 
@@ -189,7 +193,8 @@ fn introduction_builder(ast_func: &ast::Fn, ctx: &AssistContext<'_>) -> Option<S
         let intro_for_new = || {
             let is_new = name == "new";
             if is_new && ret_ty == self_ty {
-                Some(format!("Creates a new [`{}`].", linkable_self_ty?))
+                let self_ty = linkable_self_ty?;
+                Some(format!("Creates a new [`{self_ty}`]."))
             } else {
                 None
             }
@@ -214,7 +219,9 @@ fn introduction_builder(ast_func: &ast::Fn, ctx: &AssistContext<'_>) -> Option<S
                 } else {
                     ""
                 };
-                Some(format!("Returns{reference} the {what} of this [`{}`].", linkable_self_ty?))
+
+                let self_ty = linkable_self_ty?;
+                Some(format!("Returns{reference} the {what} of this [`{self_ty}`]."))
             }
             _ => None,
         };
@@ -228,7 +235,9 @@ fn introduction_builder(ast_func: &ast::Fn, ctx: &AssistContext<'_>) -> Option<S
             if what == "len" {
                 what = "length".into()
             };
-            Some(format!("Sets the {what} of this [`{}`].", linkable_self_ty?))
+
+            let self_ty = linkable_self_ty?;
+            Some(format!("Sets the {what} of this [`{self_ty}`]."))
         };
 
         if let Some(intro) = intro_for_new() {
@@ -404,7 +413,7 @@ fn arguments_from_params(param_list: &ast::ParamList) -> String {
         // instance `TuplePat`) could be managed later.
         Some(ast::Pat::IdentPat(ident_pat)) => match ident_pat.name() {
             Some(name) => match is_a_ref_mut_param(&param) {
-                true => format!("&mut {}", name),
+                true => format!("&mut {name}"),
                 false => name.to_string(),
             },
             None => "_".to_string(),
@@ -424,14 +433,15 @@ fn function_call(
     let name = ast_func.name()?;
     let arguments = arguments_from_params(param_list);
     let function_call = if param_list.self_param().is_some() {
-        format!("{}.{}({})", self_name?, name, arguments)
+        let self_ = self_name?;
+        format!("{self_}.{name}({arguments})")
     } else if let Some(implementation) = self_partial_type(ast_func) {
-        format!("{}::{}({})", implementation, name, arguments)
+        format!("{implementation}::{name}({arguments})")
     } else {
-        format!("{}({})", name, arguments)
+        format!("{name}({arguments})")
     };
     match is_unsafe {
-        true => Some(format!("unsafe {{ {} }}", function_call)),
+        true => Some(format!("unsafe {{ {function_call} }}")),
         false => Some(function_call),
     }
 }
@@ -469,8 +479,8 @@ fn build_path(ast_func: &ast::Fn, ctx: &AssistContext<'_>) -> Option<String> {
         .unwrap_or_else(|| "*".into());
     let module_def: ModuleDef = ctx.sema.to_def(ast_func)?.module(ctx.db()).into();
     match module_def.canonical_path(ctx.db()) {
-        Some(path) => Some(format!("{}::{}::{}", crate_name, path, leaf)),
-        None => Some(format!("{}::{}", crate_name, leaf)),
+        Some(path) => Some(format!("{crate_name}::{path}::{leaf}")),
+        None => Some(format!("{crate_name}::{leaf}")),
     }
 }
 
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_enum_is_method.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_enum_is_method.rs
index 52d27d8a7d63..63e91b835f1f 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_enum_is_method.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_enum_is_method.rs
@@ -52,7 +52,7 @@ pub(crate) fn generate_enum_is_method(acc: &mut Assists, ctx: &AssistContext<'_>
     let fn_name = format!("is_{}", &to_lower_snake_case(&variant_name.text()));
 
     // Return early if we've found an existing new fn
-    let impl_def = find_struct_impl(ctx, &parent_enum, &fn_name)?;
+    let impl_def = find_struct_impl(ctx, &parent_enum, &[fn_name.clone()])?;
 
     let target = variant.syntax().text_range();
     acc.add_group(
@@ -61,21 +61,15 @@ pub(crate) fn generate_enum_is_method(acc: &mut Assists, ctx: &AssistContext<'_>
         "Generate an `is_` method for this enum variant",
         target,
         |builder| {
-            let vis = parent_enum.visibility().map_or(String::new(), |v| format!("{} ", v));
+            let vis = parent_enum.visibility().map_or(String::new(), |v| format!("{v} "));
             let method = format!(
-                "    /// Returns `true` if the {} is [`{variant}`].
+                "    /// Returns `true` if the {enum_lowercase_name} is [`{variant_name}`].
     ///
-    /// [`{variant}`]: {}::{variant}
+    /// [`{variant_name}`]: {enum_name}::{variant_name}
     #[must_use]
-    {}fn {}(&self) -> bool {{
-        matches!(self, Self::{variant}{})
+    {vis}fn {fn_name}(&self) -> bool {{
+        matches!(self, Self::{variant_name}{pattern_suffix})
     }}",
-                enum_lowercase_name,
-                enum_name,
-                vis,
-                fn_name,
-                pattern_suffix,
-                variant = variant_name
             );
 
             add_method_to_adt(builder, &parent_enum, impl_def, &method);
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_enum_projection_method.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_enum_projection_method.rs
index b19aa0f652aa..c9aa41c845ad 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_enum_projection_method.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_enum_projection_method.rs
@@ -116,6 +116,15 @@ fn generate_enum_projection_method(
     assist_description: &str,
     props: ProjectionProps,
 ) -> Option<()> {
+    let ProjectionProps {
+        fn_name_prefix,
+        self_param,
+        return_prefix,
+        return_suffix,
+        happy_case,
+        sad_case,
+    } = props;
+
     let variant = ctx.find_node_at_offset::<ast::Variant>()?;
     let variant_name = variant.name()?;
     let parent_enum = ast::Adt::Enum(variant.parent_enum());
@@ -125,7 +134,7 @@ fn generate_enum_projection_method(
             let (field,) = record.fields().collect_tuple()?;
             let name = field.name()?.to_string();
             let ty = field.ty()?;
-            let pattern_suffix = format!(" {{ {} }}", name);
+            let pattern_suffix = format!(" {{ {name} }}");
             (pattern_suffix, ty, name)
         }
         ast::StructKind::Tuple(tuple) => {
@@ -136,11 +145,10 @@ fn generate_enum_projection_method(
         ast::StructKind::Unit => return None,
     };
 
-    let fn_name =
-        format!("{}_{}", props.fn_name_prefix, &to_lower_snake_case(&variant_name.text()));
+    let fn_name = format!("{fn_name_prefix}_{}", &to_lower_snake_case(&variant_name.text()));
 
     // Return early if we've found an existing new fn
-    let impl_def = find_struct_impl(ctx, &parent_enum, &fn_name)?;
+    let impl_def = find_struct_impl(ctx, &parent_enum, &[fn_name.clone()])?;
 
     let target = variant.syntax().text_range();
     acc.add_group(
@@ -150,25 +158,23 @@ fn generate_enum_projection_method(
         target,
         |builder| {
             let vis = parent_enum.visibility().map_or(String::new(), |v| format!("{} ", v));
+
+            let field_type_syntax = field_type.syntax();
+
+            let must_use = if ctx.config.assist_emit_must_use {
+                "#[must_use]\n    "
+            } else {
+                ""
+            };
+
             let method = format!(
-                "    {0}fn {1}({2}) -> {3}{4}{5} {{
-        if let Self::{6}{7} = self {{
-            {8}({9})
+                "    {must_use}{vis}fn {fn_name}({self_param}) -> {return_prefix}{field_type_syntax}{return_suffix} {{
+        if let Self::{variant_name}{pattern_suffix} = self {{
+            {happy_case}({bound_name})
         }} else {{
-            {10}
+            {sad_case}
         }}
-    }}",
-                vis,
-                fn_name,
-                props.self_param,
-                props.return_prefix,
-                field_type.syntax(),
-                props.return_suffix,
-                variant_name,
-                pattern_suffix,
-                props.happy_case,
-                bound_name,
-                props.sad_case,
+    }}"
             );
 
             add_method_to_adt(builder, &parent_enum, impl_def, &method);
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_from_impl_for_enum.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_from_impl_for_enum.rs
index 507ea012babf..7c81d2c6a6cc 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_from_impl_for_enum.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_from_impl_for_enum.rs
@@ -56,23 +56,18 @@ pub(crate) fn generate_from_impl_for_enum(
         target,
         |edit| {
             let start_offset = variant.parent_enum().syntax().text_range().end();
-            let from_trait = format!("From<{}>", field_type.syntax());
+            let from_trait = format!("From<{field_type}>");
             let impl_code = if let Some(name) = field_name {
                 format!(
-                    r#"    fn from({0}: {1}) -> Self {{
-        Self::{2} {{ {0} }}
-    }}"#,
-                    name.text(),
-                    field_type.syntax(),
-                    variant_name,
+                    r#"    fn from({name}: {field_type}) -> Self {{
+        Self::{variant_name} {{ {name} }}
+    }}"#
                 )
             } else {
                 format!(
-                    r#"    fn from(v: {}) -> Self {{
-        Self::{}(v)
-    }}"#,
-                    field_type.syntax(),
-                    variant_name,
+                    r#"    fn from(v: {field_type}) -> Self {{
+        Self::{variant_name}(v)
+    }}"#
                 )
             };
             let from_impl = generate_trait_impl_text(&enum_, &from_trait, &impl_code);
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_function.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_function.rs
index 8b67982f9158..c229127e48ff 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_function.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_function.rs
@@ -179,7 +179,7 @@ fn add_func_to_accumulator(
         let function_template = function_builder.render(adt_name.is_some());
         let mut func = function_template.to_string(ctx.config.snippet_cap);
         if let Some(name) = adt_name {
-            func = format!("\n{}impl {} {{\n{}\n{}}}", indent, name, func, indent);
+            func = format!("\n{indent}impl {name} {{\n{func}\n{indent}}}");
         }
         builder.edit_file(file);
         match ctx.config.snippet_cap {
@@ -198,7 +198,7 @@ fn get_adt_source(
     let file = ctx.sema.parse(range.file_id);
     let adt_source =
         ctx.sema.find_node_at_offset_with_macros(file.syntax(), range.range.start())?;
-    find_struct_impl(ctx, &adt_source, fn_name).map(|impl_| (impl_, range.file_id))
+    find_struct_impl(ctx, &adt_source, &[fn_name.to_string()]).map(|impl_| (impl_, range.file_id))
 }
 
 struct FunctionTemplate {
@@ -212,23 +212,26 @@ struct FunctionTemplate {
 
 impl FunctionTemplate {
     fn to_string(&self, cap: Option<SnippetCap>) -> String {
+        let Self { leading_ws, fn_def, ret_type, should_focus_return_type, trailing_ws, tail_expr } =
+            self;
+
         let f = match cap {
             Some(cap) => {
-                let cursor = if self.should_focus_return_type {
+                let cursor = if *should_focus_return_type {
                     // Focus the return type if there is one
-                    match self.ret_type {
-                        Some(ref ret_type) => ret_type.syntax(),
-                        None => self.tail_expr.syntax(),
+                    match ret_type {
+                        Some(ret_type) => ret_type.syntax(),
+                        None => tail_expr.syntax(),
                     }
                 } else {
-                    self.tail_expr.syntax()
+                    tail_expr.syntax()
                 };
-                render_snippet(cap, self.fn_def.syntax(), Cursor::Replace(cursor))
+                render_snippet(cap, fn_def.syntax(), Cursor::Replace(cursor))
             }
-            None => self.fn_def.to_string(),
+            None => fn_def.to_string(),
         };
 
-        format!("{}{}{}", self.leading_ws, f, self.trailing_ws)
+        format!("{leading_ws}{f}{trailing_ws}")
     }
 }
 
@@ -330,9 +333,9 @@ impl FunctionBuilder {
                 let mut indent = IndentLevel::from_node(&it);
                 if is_method {
                     indent = indent + 1;
-                    leading_ws = format!("{}", indent);
+                    leading_ws = format!("{indent}");
                 } else {
-                    leading_ws = format!("\n\n{}", indent);
+                    leading_ws = format!("\n\n{indent}");
                 }
 
                 fn_def = fn_def.indent(indent);
@@ -340,9 +343,10 @@ impl FunctionBuilder {
             }
             GeneratedFunctionTarget::InEmptyItemList(it) => {
                 let indent = IndentLevel::from_node(&it);
-                leading_ws = format!("\n{}", indent + 1);
-                fn_def = fn_def.indent(indent + 1);
-                trailing_ws = format!("\n{}", indent);
+                let leading_indent = indent + 1;
+                leading_ws = format!("\n{leading_indent}");
+                fn_def = fn_def.indent(leading_indent);
+                trailing_ws = format!("\n{indent}");
             }
         };
 
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_getter.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_getter.rs
index 76fcef0cad95..5e7191428349 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_getter.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_getter.rs
@@ -1,6 +1,9 @@
 use ide_db::famous_defs::FamousDefs;
 use stdx::{format_to, to_lower_snake_case};
-use syntax::ast::{self, AstNode, HasName, HasVisibility};
+use syntax::{
+    ast::{self, AstNode, HasName, HasVisibility},
+    TextRange,
+};
 
 use crate::{
     utils::{convert_reference_type, find_impl_block_end, find_struct_impl, generate_impl_text},
@@ -72,92 +75,259 @@ pub(crate) fn generate_getter_mut(acc: &mut Assists, ctx: &AssistContext<'_>) ->
     generate_getter_impl(acc, ctx, true)
 }
 
+#[derive(Clone, Debug)]
+struct RecordFieldInfo {
+    field_name: syntax::ast::Name,
+    field_ty: syntax::ast::Type,
+    fn_name: String,
+    target: TextRange,
+}
+
+struct GetterInfo {
+    impl_def: Option<ast::Impl>,
+    strukt: ast::Struct,
+    mutable: bool,
+}
+
 pub(crate) fn generate_getter_impl(
     acc: &mut Assists,
     ctx: &AssistContext<'_>,
     mutable: bool,
 ) -> Option<()> {
-    let strukt = ctx.find_node_at_offset::<ast::Struct>()?;
-    let field = ctx.find_node_at_offset::<ast::RecordField>()?;
+    // This if condition denotes two modes this assist can work in:
+    // - First is acting upon selection of record fields
+    // - Next is acting upon a single record field
+    //
+    // This is the only part where implementation diverges a bit,
+    // subsequent code is generic for both of these modes
 
-    let field_name = field.name()?;
-    let field_ty = field.ty()?;
+    let (strukt, info_of_record_fields, fn_names) = if !ctx.has_empty_selection() {
+        // Selection Mode
+        let node = ctx.covering_element();
 
-    // Return early if we've found an existing fn
-    let mut fn_name = to_lower_snake_case(&field_name.to_string());
-    if mutable {
-        format_to!(fn_name, "_mut");
+        let node = match node {
+            syntax::NodeOrToken::Node(n) => n,
+            syntax::NodeOrToken::Token(t) => t.parent()?,
+        };
+
+        let parent_struct = node.ancestors().find_map(ast::Struct::cast)?;
+
+        let (info_of_record_fields, field_names) =
+            extract_and_parse_record_fields(&parent_struct, ctx.selection_trimmed(), mutable)?;
+
+        (parent_struct, info_of_record_fields, field_names)
+    } else {
+        // Single Record Field mode
+        let strukt = ctx.find_node_at_offset::<ast::Struct>()?;
+        let field = ctx.find_node_at_offset::<ast::RecordField>()?;
+
+        let record_field_info = parse_record_field(field, mutable)?;
+
+        let fn_name = record_field_info.fn_name.clone();
+
+        (strukt, vec![record_field_info], vec![fn_name])
+    };
+
+    // No record fields to do work on :(
+    if info_of_record_fields.len() == 0 {
+        return None;
     }
-    let impl_def = find_struct_impl(ctx, &ast::Adt::Struct(strukt.clone()), fn_name.as_str())?;
+
+    let impl_def = find_struct_impl(ctx, &ast::Adt::Struct(strukt.clone()), &fn_names)?;
 
     let (id, label) = if mutable {
         ("generate_getter_mut", "Generate a mut getter method")
     } else {
         ("generate_getter", "Generate a getter method")
     };
-    let target = field.syntax().text_range();
+
+    // Computing collective text range of all record fields in selected region
+    let target: TextRange = info_of_record_fields
+        .iter()
+        .map(|record_field_info| record_field_info.target)
+        .reduce(|acc, target| acc.cover(target))?;
+
+    let getter_info = GetterInfo { impl_def, strukt, mutable };
+
     acc.add_group(
         &GroupLabel("Generate getter/setter".to_owned()),
         AssistId(id, AssistKind::Generate),
         label,
         target,
         |builder| {
+            let record_fields_count = info_of_record_fields.len();
+
             let mut buf = String::with_capacity(512);
 
-            if impl_def.is_some() {
-                buf.push('\n');
+            // Check if an impl exists
+            if let Some(impl_def) = &getter_info.impl_def {
+                // Check if impl is empty
+                if let Some(assoc_item_list) = impl_def.assoc_item_list() {
+                    if assoc_item_list.assoc_items().next().is_some() {
+                        // If not empty then only insert a new line
+                        buf.push('\n');
+                    }
+                }
             }
 
-            let vis = strukt.visibility().map_or(String::new(), |v| format!("{} ", v));
-            let (ty, body) = if mutable {
-                (format!("&mut {}", field_ty), format!("&mut self.{}", field_name))
-            } else {
-                (|| {
-                    let krate = ctx.sema.scope(field_ty.syntax())?.krate();
-                    let famous_defs = &FamousDefs(&ctx.sema, krate);
-                    ctx.sema
-                        .resolve_type(&field_ty)
-                        .and_then(|ty| convert_reference_type(ty, ctx.db(), famous_defs))
-                        .map(|conversion| {
-                            cov_mark::hit!(convert_reference_type);
-                            (
-                                conversion.convert_type(ctx.db()),
-                                conversion.getter(field_name.to_string()),
-                            )
-                        })
-                })()
-                .unwrap_or_else(|| (format!("&{}", field_ty), format!("&self.{}", field_name)))
-            };
+            for (i, record_field_info) in info_of_record_fields.iter().enumerate() {
+                // this buf inserts a newline at the end of a getter
+                // automatically, if one wants to add one more newline
+                // for separating it from other assoc items, that needs
+                // to be handled spearately
+                let mut getter_buf =
+                    generate_getter_from_info(ctx, &getter_info, &record_field_info);
 
-            format_to!(
-                buf,
-                "    {}fn {}(&{}self) -> {} {{
-        {}
-    }}",
-                vis,
-                fn_name,
-                mutable.then(|| "mut ").unwrap_or_default(),
-                ty,
-                body,
-            );
+                // Insert `$0` only for last getter we generate
+                if i == record_fields_count - 1 {
+                    getter_buf = getter_buf.replacen("fn ", "fn $0", 1);
+                }
 
-            let start_offset = impl_def
-                .and_then(|impl_def| find_impl_block_end(impl_def, &mut buf))
+                // For first element we do not merge with '\n', as
+                // that can be inserted by impl_def check defined
+                // above, for other cases which are:
+                //
+                // - impl exists but it empty, here we would ideally
+                // not want to keep newline between impl <struct> {
+                // and fn <fn-name>() { line
+                //
+                // - next if impl itself does not exist, in this
+                // case we ourselves generate a new impl and that
+                // again ends up with the same reasoning as above
+                // for not keeping newline
+                if i == 0 {
+                    buf = buf + &getter_buf;
+                } else {
+                    buf = buf + "\n" + &getter_buf;
+                }
+
+                // We don't insert a new line at the end of
+                // last getter as it will end up in the end
+                // of an impl where we would not like to keep
+                // getter and end of impl ( i.e. `}` ) with an
+                // extra line for no reason
+                if i < record_fields_count - 1 {
+                    buf = buf + "\n";
+                }
+            }
+
+            let start_offset = getter_info
+                .impl_def
+                .as_ref()
+                .and_then(|impl_def| find_impl_block_end(impl_def.to_owned(), &mut buf))
                 .unwrap_or_else(|| {
-                    buf = generate_impl_text(&ast::Adt::Struct(strukt.clone()), &buf);
-                    strukt.syntax().text_range().end()
+                    buf = generate_impl_text(&ast::Adt::Struct(getter_info.strukt.clone()), &buf);
+                    getter_info.strukt.syntax().text_range().end()
                 });
 
             match ctx.config.snippet_cap {
-                Some(cap) => {
-                    builder.insert_snippet(cap, start_offset, buf.replacen("fn ", "fn $0", 1))
-                }
+                Some(cap) => builder.insert_snippet(cap, start_offset, buf),
                 None => builder.insert(start_offset, buf),
             }
         },
     )
 }
 
+fn generate_getter_from_info(
+    ctx: &AssistContext<'_>,
+    info: &GetterInfo,
+    record_field_info: &RecordFieldInfo,
+) -> String {
+    let mut buf = String::with_capacity(512);
+
+    let vis = info.strukt.visibility().map_or(String::new(), |v| format!("{} ", v));
+    let (ty, body) = if info.mutable {
+        (
+            format!("&mut {}", record_field_info.field_ty),
+            format!("&mut self.{}", record_field_info.field_name),
+        )
+    } else {
+        (|| {
+            let krate = ctx.sema.scope(record_field_info.field_ty.syntax())?.krate();
+            let famous_defs = &FamousDefs(&ctx.sema, krate);
+            ctx.sema
+                .resolve_type(&record_field_info.field_ty)
+                .and_then(|ty| convert_reference_type(ty, ctx.db(), famous_defs))
+                .map(|conversion| {
+                    cov_mark::hit!(convert_reference_type);
+                    (
+                        conversion.convert_type(ctx.db()),
+                        conversion.getter(record_field_info.field_name.to_string()),
+                    )
+                })
+        })()
+        .unwrap_or_else(|| {
+            (
+                format!("&{}", record_field_info.field_ty),
+                format!("&self.{}", record_field_info.field_name),
+            )
+        })
+    };
+
+    format_to!(
+        buf,
+        "    {}fn {}(&{}self) -> {} {{
+        {}
+    }}",
+        vis,
+        record_field_info.fn_name,
+        info.mutable.then(|| "mut ").unwrap_or_default(),
+        ty,
+        body,
+    );
+
+    buf
+}
+
+fn extract_and_parse_record_fields(
+    node: &ast::Struct,
+    selection_range: TextRange,
+    mutable: bool,
+) -> Option<(Vec<RecordFieldInfo>, Vec<String>)> {
+    let mut field_names: Vec<String> = vec![];
+    let field_list = node.field_list()?;
+
+    match field_list {
+        ast::FieldList::RecordFieldList(ele) => {
+            let info_of_record_fields_in_selection = ele
+                .fields()
+                .filter_map(|record_field| {
+                    if selection_range.contains_range(record_field.syntax().text_range()) {
+                        let record_field_info = parse_record_field(record_field, mutable)?;
+                        field_names.push(record_field_info.fn_name.clone());
+                        return Some(record_field_info);
+                    }
+
+                    None
+                })
+                .collect::<Vec<RecordFieldInfo>>();
+
+            if info_of_record_fields_in_selection.len() == 0 {
+                return None;
+            }
+
+            Some((info_of_record_fields_in_selection, field_names))
+        }
+        ast::FieldList::TupleFieldList(_) => {
+            return None;
+        }
+    }
+}
+
+fn parse_record_field(record_field: ast::RecordField, mutable: bool) -> Option<RecordFieldInfo> {
+    let field_name = record_field.name()?;
+    let field_ty = record_field.ty()?;
+
+    let mut fn_name = to_lower_snake_case(&field_name.to_string());
+    if mutable {
+        format_to!(fn_name, "_mut");
+    }
+
+    let target = record_field.syntax().text_range();
+
+    Some(RecordFieldInfo { field_name, field_ty, fn_name, target })
+}
+
 #[cfg(test)]
 mod tests {
     use crate::tests::{check_assist, check_assist_not_applicable};
@@ -489,4 +659,53 @@ impl Context {
 "#,
         );
     }
+
+    #[test]
+    fn test_generate_multiple_getters_from_selection() {
+        check_assist(
+            generate_getter,
+            r#"
+struct Context {
+    $0data: Data,
+    count: usize,$0
+}
+    "#,
+            r#"
+struct Context {
+    data: Data,
+    count: usize,
+}
+
+impl Context {
+    fn data(&self) -> &Data {
+        &self.data
+    }
+
+    fn $0count(&self) -> &usize {
+        &self.count
+    }
+}
+    "#,
+        );
+    }
+
+    #[test]
+    fn test_generate_multiple_getters_from_selection_one_already_exists() {
+        // As impl for one of the fields already exist, skip it
+        check_assist_not_applicable(
+            generate_getter,
+            r#"
+struct Context {
+    $0data: Data,
+    count: usize,$0
+}
+
+impl Context {
+    fn data(&self) -> &Data {
+        &self.data
+    }
+}
+    "#,
+        );
+    }
 }
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_impl.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_impl.rs
index 307cea3d0a4f..9af26c04eb45 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_impl.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_impl.rs
@@ -28,7 +28,7 @@ pub(crate) fn generate_impl(acc: &mut Assists, ctx: &AssistContext<'_>) -> Optio
 
     acc.add(
         AssistId("generate_impl", AssistKind::Generate),
-        format!("Generate impl for `{}`", name),
+        format!("Generate impl for `{name}`"),
         target,
         |edit| {
             let start_offset = nominal.syntax().text_range().end();
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_new.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_new.rs
index 9cda74d9e0d3..17fadea0eaf1 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_new.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_new.rs
@@ -39,7 +39,8 @@ pub(crate) fn generate_new(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option
     };
 
     // Return early if we've found an existing new fn
-    let impl_def = find_struct_impl(ctx, &ast::Adt::Struct(strukt.clone()), "new")?;
+    let impl_def =
+        find_struct_impl(ctx, &ast::Adt::Struct(strukt.clone()), &[String::from("new")])?;
 
     let current_module = ctx.sema.scope(strukt.syntax())?.module();
 
@@ -51,11 +52,13 @@ pub(crate) fn generate_new(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option
             buf.push('\n');
         }
 
-        let vis = strukt.visibility().map_or(String::new(), |v| format!("{} ", v));
+        let vis = strukt.visibility().map_or(String::new(), |v| format!("{v} "));
 
         let trivial_constructors = field_list
             .fields()
             .map(|f| {
+                let name = f.name()?;
+
                 let ty = ctx.sema.resolve_type(&f.ty()?)?;
 
                 let item_in_ns = hir::ItemInNs::from(hir::ModuleDef::from(ty.as_adt()?));
@@ -72,7 +75,7 @@ pub(crate) fn generate_new(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option
                     &ty,
                 )?;
 
-                Some(format!("{}: {}", f.name()?.syntax(), expr))
+                Some(format!("{name}: {expr}"))
             })
             .collect::<Vec<_>>();
 
@@ -81,7 +84,10 @@ pub(crate) fn generate_new(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option
             .enumerate()
             .filter_map(|(i, f)| {
                 if trivial_constructors[i].is_none() {
-                    Some(format!("{}: {}", f.name()?.syntax(), f.ty()?.syntax()))
+                    let name = f.name()?;
+                    let ty = f.ty()?;
+
+                    Some(format!("{name}: {ty}"))
                 } else {
                     None
                 }
@@ -101,7 +107,7 @@ pub(crate) fn generate_new(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option
             })
             .format(", ");
 
-        format_to!(buf, "    {}fn new({}) -> Self {{ Self {{ {} }} }}", vis, params, fields);
+        format_to!(buf, "    {vis}fn new({params}) -> Self {{ Self {{ {fields} }} }}");
 
         let start_offset = impl_def
             .and_then(|impl_def| find_impl_block_start(impl_def, &mut buf))
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_setter.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_setter.rs
index 2a7ad6ce3681..62f72df1c9d6 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_setter.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_setter.rs
@@ -36,11 +36,8 @@ pub(crate) fn generate_setter(acc: &mut Assists, ctx: &AssistContext<'_>) -> Opt
 
     // Return early if we've found an existing fn
     let fn_name = to_lower_snake_case(&field_name.to_string());
-    let impl_def = find_struct_impl(
-        ctx,
-        &ast::Adt::Struct(strukt.clone()),
-        format!("set_{}", fn_name).as_str(),
-    )?;
+    let impl_def =
+        find_struct_impl(ctx, &ast::Adt::Struct(strukt.clone()), &[format!("set_{fn_name}")])?;
 
     let target = field.syntax().text_range();
     acc.add_group(
@@ -55,18 +52,12 @@ pub(crate) fn generate_setter(acc: &mut Assists, ctx: &AssistContext<'_>) -> Opt
                 buf.push('\n');
             }
 
-            let vis = strukt.visibility().map_or(String::new(), |v| format!("{} ", v));
+            let vis = strukt.visibility().map_or(String::new(), |v| format!("{v} "));
             format_to!(
                 buf,
-                "    {}fn set_{}(&mut self, {}: {}) {{
-        self.{} = {};
-    }}",
-                vis,
-                fn_name,
-                fn_name,
-                field_ty,
-                fn_name,
-                fn_name,
+                "    {vis}fn set_{fn_name}(&mut self, {fn_name}: {field_ty}) {{
+        self.{fn_name} = {fn_name};
+    }}"
             );
 
             let start_offset = impl_def
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/inline_call.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/inline_call.rs
index 9f51cdaf8b1e..0c546ce5d41c 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/inline_call.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/inline_call.rs
@@ -1,3 +1,5 @@
+use std::collections::BTreeSet;
+
 use ast::make;
 use either::Either;
 use hir::{db::HirDatabase, PathResolution, Semantics, TypeInfo};
@@ -190,10 +192,10 @@ pub(crate) fn inline_call(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<
                 PathResolution::Def(hir::ModuleDef::Function(f)) => f,
                 _ => return None,
             };
-            (function, format!("Inline `{}`", path))
+            (function, format!("Inline `{path}`"))
         }
         ast::CallableExpr::MethodCall(call) => {
-            (ctx.sema.resolve_method_call(call)?, format!("Inline `{}`", name_ref))
+            (ctx.sema.resolve_method_call(call)?, format!("Inline `{name_ref}`"))
         }
     };
 
@@ -373,8 +375,44 @@ fn inline(
                 })
         }
     }
+
+    let mut func_let_vars: BTreeSet<String> = BTreeSet::new();
+
+    // grab all of the local variable declarations in the function
+    for stmt in fn_body.statements() {
+        if let Some(let_stmt) = ast::LetStmt::cast(stmt.syntax().to_owned()) {
+            for has_token in let_stmt.syntax().children_with_tokens() {
+                if let Some(node) = has_token.as_node() {
+                    if let Some(ident_pat) = ast::IdentPat::cast(node.to_owned()) {
+                        func_let_vars.insert(ident_pat.syntax().text().to_string());
+                    }
+                }
+            }
+        }
+    }
+
     // Inline parameter expressions or generate `let` statements depending on whether inlining works or not.
     for ((pat, param_ty, _), usages, expr) in izip!(params, param_use_nodes, arguments).rev() {
+        // izip confuses RA due to our lack of hygiene info currently losing us type info causing incorrect errors
+        let usages: &[ast::PathExpr] = &*usages;
+        let expr: &ast::Expr = expr;
+
+        let insert_let_stmt = || {
+            let ty = sema.type_of_expr(expr).filter(TypeInfo::has_adjustment).and(param_ty.clone());
+            if let Some(stmt_list) = body.stmt_list() {
+                stmt_list.push_front(
+                    make::let_stmt(pat.clone(), ty, Some(expr.clone())).clone_for_update().into(),
+                )
+            }
+        };
+
+        // check if there is a local var in the function that conflicts with parameter
+        // if it does then emit a let statement and continue
+        if func_let_vars.contains(&expr.syntax().text().to_string()) {
+            insert_let_stmt();
+            continue;
+        }
+
         let inline_direct = |usage, replacement: &ast::Expr| {
             if let Some(field) = path_expr_as_record_field(usage) {
                 cov_mark::hit!(inline_call_inline_direct_field);
@@ -383,9 +421,7 @@ fn inline(
                 ted::replace(usage.syntax(), &replacement.syntax().clone_for_update());
             }
         };
-        // izip confuses RA due to our lack of hygiene info currently losing us type info causing incorrect errors
-        let usages: &[ast::PathExpr] = &*usages;
-        let expr: &ast::Expr = expr;
+
         match usages {
             // inline single use closure arguments
             [usage]
@@ -408,18 +444,11 @@ fn inline(
             }
             // can't inline, emit a let statement
             _ => {
-                let ty =
-                    sema.type_of_expr(expr).filter(TypeInfo::has_adjustment).and(param_ty.clone());
-                if let Some(stmt_list) = body.stmt_list() {
-                    stmt_list.push_front(
-                        make::let_stmt(pat.clone(), ty, Some(expr.clone()))
-                            .clone_for_update()
-                            .into(),
-                    )
-                }
+                insert_let_stmt();
             }
         }
     }
+
     if let Some(generic_arg_list) = generic_arg_list.clone() {
         if let Some((target, source)) = &sema.scope(node.syntax()).zip(sema.scope(fn_body.syntax()))
         {
@@ -1256,4 +1285,37 @@ impl A {
 "#,
         )
     }
+
+    #[test]
+    fn local_variable_shadowing_callers_argument() {
+        check_assist(
+            inline_call,
+            r#"
+fn foo(bar: u32, baz: u32) -> u32 {
+    let a = 1;
+    bar * baz * a * 6
+}
+fn main() {
+    let a = 7;
+    let b = 1;
+    let res = foo$0(a, b);
+}
+"#,
+            r#"
+fn foo(bar: u32, baz: u32) -> u32 {
+    let a = 1;
+    bar * baz * a * 6
+}
+fn main() {
+    let a = 7;
+    let b = 1;
+    let res = {
+        let bar = a;
+        let a = 1;
+        bar * b * a * 6
+    };
+}
+"#,
+        );
+    }
 }
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/inline_local_variable.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/inline_local_variable.rs
index 7259d6781941..ce44100e34be 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/inline_local_variable.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/inline_local_variable.rs
@@ -113,7 +113,7 @@ pub(crate) fn inline_local_variable(acc: &mut Assists, ctx: &AssistContext<'_>)
         .collect::<Option<Vec<_>>>()?;
 
     let init_str = initializer_expr.syntax().text().to_string();
-    let init_in_paren = format!("({})", &init_str);
+    let init_in_paren = format!("({init_str})");
 
     let target = match target {
         ast::NameOrNameRef::Name(it) => it.syntax().text_range(),
@@ -132,7 +132,7 @@ pub(crate) fn inline_local_variable(acc: &mut Assists, ctx: &AssistContext<'_>)
                 let replacement = if should_wrap { &init_in_paren } else { &init_str };
                 if ast::RecordExprField::for_field_name(&name).is_some() {
                     cov_mark::hit!(inline_field_shorthand);
-                    builder.insert(range.end(), format!(": {}", replacement));
+                    builder.insert(range.end(), format!(": {replacement}"));
                 } else {
                     builder.replace(range, replacement.clone())
                 }
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/introduce_named_lifetime.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/introduce_named_lifetime.rs
index 2fc754e3e50d..a54dc4f96de0 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/introduce_named_lifetime.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/introduce_named_lifetime.rs
@@ -127,7 +127,7 @@ fn generate_unique_lifetime_param_name(
         Some(type_params) => {
             let used_lifetime_params: FxHashSet<_> =
                 type_params.lifetime_params().map(|p| p.syntax().text().to_string()).collect();
-            ('a'..='z').map(|it| format!("'{}", it)).find(|it| !used_lifetime_params.contains(it))
+            ('a'..='z').map(|it| format!("'{it}")).find(|it| !used_lifetime_params.contains(it))
         }
         None => Some("'a".to_string()),
     }
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/merge_match_arms.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/merge_match_arms.rs
index c24015b1c517..641c90885bf5 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/merge_match_arms.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/merge_match_arms.rs
@@ -78,7 +78,7 @@ pub(crate) fn merge_match_arms(acc: &mut Assists, ctx: &AssistContext<'_>) -> Op
                     .join(" | ")
             };
 
-            let arm = format!("{} => {},", pats, current_expr.syntax().text());
+            let arm = format!("{pats} => {current_expr},");
 
             if let [first, .., last] = &*arms_to_merge {
                 let start = first.syntax().text_range().start();
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/move_from_mod_rs.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/move_from_mod_rs.rs
index a6c85a2b18b3..1728c03cd03e 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/move_from_mod_rs.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/move_from_mod_rs.rs
@@ -40,11 +40,11 @@ pub(crate) fn move_from_mod_rs(acc: &mut Assists, ctx: &AssistContext<'_>) -> Op
 
     let target = source_file.syntax().text_range();
     let module_name = module.name(ctx.db())?.to_string();
-    let path = format!("../{}.rs", module_name);
+    let path = format!("../{module_name}.rs");
     let dst = AnchoredPathBuf { anchor: ctx.file_id(), path };
     acc.add(
         AssistId("move_from_mod_rs", AssistKind::Refactor),
-        format!("Convert {}/mod.rs to {}.rs", module_name, module_name),
+        format!("Convert {module_name}/mod.rs to {module_name}.rs"),
         target,
         |builder| {
             builder.move_file(ctx.file_id(), dst);
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/move_guard.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/move_guard.rs
index b8f1b36deb93..ec3281619cc3 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/move_guard.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/move_guard.rs
@@ -133,16 +133,16 @@ pub(crate) fn move_arm_cond_to_match_guard(
             };
             let then_arm_end = match_arm.syntax().text_range().end();
             let indent_level = match_arm.indent_level();
-            let spaces = "    ".repeat(indent_level.0 as _);
+            let spaces = indent_level;
 
             let mut first = true;
             for (cond, block) in conds_blocks {
                 if !first {
-                    edit.insert(then_arm_end, format!("\n{}", spaces));
+                    edit.insert(then_arm_end, format!("\n{spaces}"));
                 } else {
                     first = false;
                 }
-                let guard = format!("{} if {} => ", match_pat, cond.syntax().text());
+                let guard = format!("{match_pat} if {cond} => ");
                 edit.insert(then_arm_end, guard);
                 let only_expr = block.statements().next().is_none();
                 match &block.tail_expr() {
@@ -158,7 +158,7 @@ pub(crate) fn move_arm_cond_to_match_guard(
             }
             if let Some(e) = tail {
                 cov_mark::hit!(move_guard_ifelse_else_tail);
-                let guard = format!("\n{}{} => ", spaces, match_pat);
+                let guard = format!("\n{spaces}{match_pat} => ");
                 edit.insert(then_arm_end, guard);
                 let only_expr = e.statements().next().is_none();
                 match &e.tail_expr() {
@@ -183,7 +183,7 @@ pub(crate) fn move_arm_cond_to_match_guard(
                     {
                         cov_mark::hit!(move_guard_ifelse_has_wildcard);
                     }
-                    _ => edit.insert(then_arm_end, format!("\n{}{} => {{}}", spaces, match_pat)),
+                    _ => edit.insert(then_arm_end, format!("\n{spaces}{match_pat} => {{}}")),
                 }
             }
         },
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/move_module_to_file.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/move_module_to_file.rs
index 7468318a594a..a7c605325ea6 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/move_module_to_file.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/move_module_to_file.rs
@@ -52,7 +52,7 @@ pub(crate) fn move_module_to_file(acc: &mut Assists, ctx: &AssistContext<'_>) ->
                 let mut buf = String::from("./");
                 match parent_module.name(ctx.db()) {
                     Some(name) if !parent_module.is_mod_rs(ctx.db()) => {
-                        format_to!(buf, "{}/", name)
+                        format_to!(buf, "{name}/")
                     }
                     _ => (),
                 }
@@ -82,7 +82,7 @@ pub(crate) fn move_module_to_file(acc: &mut Assists, ctx: &AssistContext<'_>) ->
                 items
             };
 
-            let buf = format!("mod {};", module_name);
+            let buf = format!("mod {module_name};");
 
             let replacement_start = match module_ast.mod_token() {
                 Some(mod_token) => mod_token.text_range(),
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/move_to_mod_rs.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/move_to_mod_rs.rs
index a909ce8b2679..076d25411a81 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/move_to_mod_rs.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/move_to_mod_rs.rs
@@ -40,11 +40,11 @@ pub(crate) fn move_to_mod_rs(acc: &mut Assists, ctx: &AssistContext<'_>) -> Opti
 
     let target = source_file.syntax().text_range();
     let module_name = module.name(ctx.db())?.to_string();
-    let path = format!("./{}/mod.rs", module_name);
+    let path = format!("./{module_name}/mod.rs");
     let dst = AnchoredPathBuf { anchor: ctx.file_id(), path };
     acc.add(
         AssistId("move_to_mod_rs", AssistKind::Refactor),
-        format!("Convert {}.rs to {}/mod.rs", module_name, module_name),
+        format!("Convert {module_name}.rs to {module_name}/mod.rs"),
         target,
         |builder| {
             builder.move_file(ctx.file_id(), dst);
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/number_representation.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/number_representation.rs
index 424db7437a74..7e3fef516bfd 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/number_representation.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/number_representation.rs
@@ -38,7 +38,7 @@ pub(crate) fn reformat_number_literal(acc: &mut Assists, ctx: &AssistContext<'_>
     converted.push_str(suffix);
 
     let group_id = GroupLabel("Reformat number literal".into());
-    let label = format!("Convert {} to {}", literal, converted);
+    let label = format!("Convert {literal} to {converted}");
     let range = literal.syntax().text_range();
     acc.add_group(
         &group_id,
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/qualify_method_call.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/qualify_method_call.rs
index e57d1d065d62..1ea87429c509 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/qualify_method_call.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/qualify_method_call.rs
@@ -54,7 +54,7 @@ pub(crate) fn qualify_method_call(acc: &mut Assists, ctx: &AssistContext<'_>) ->
 
     acc.add(
         AssistId("qualify_method_call", AssistKind::RefactorInline),
-        format!("Qualify `{}` method call", ident.text()),
+        format!("Qualify `{ident}` method call"),
         range,
         |builder| {
             qualify_candidate.qualify(
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/qualify_path.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/qualify_path.rs
index 4b2af550bc5e..e759e1561cbd 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/qualify_path.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/qualify_path.rs
@@ -118,14 +118,14 @@ impl QualifyCandidate<'_> {
         match self {
             QualifyCandidate::QualifierStart(segment, generics) => {
                 let generics = generics.as_ref().map_or_else(String::new, ToString::to_string);
-                replacer(format!("{}{}::{}", import, generics, segment));
+                replacer(format!("{import}{generics}::{segment}"));
             }
             QualifyCandidate::UnqualifiedName(generics) => {
                 let generics = generics.as_ref().map_or_else(String::new, ToString::to_string);
-                replacer(format!("{}{}", import, generics));
+                replacer(format!("{import}{generics}"));
             }
             QualifyCandidate::TraitAssocItem(qualifier, segment) => {
-                replacer(format!("<{} as {}>::{}", qualifier, import, segment));
+                replacer(format!("<{qualifier} as {import}>::{segment}"));
             }
             QualifyCandidate::TraitMethod(db, mcall_expr) => {
                 Self::qualify_trait_method(db, mcall_expr, replacer, import, item);
@@ -155,16 +155,11 @@ impl QualifyCandidate<'_> {
                 hir::Access::Exclusive => make::expr_ref(receiver, true),
                 hir::Access::Owned => receiver,
             };
-            replacer(format!(
-                "{}::{}{}{}",
-                import,
-                method_name,
-                generics,
-                match arg_list {
-                    Some(args) => make::arg_list(iter::once(receiver).chain(args)),
-                    None => make::arg_list(iter::once(receiver)),
-                }
-            ));
+            let arg_list = match arg_list {
+                Some(args) => make::arg_list(iter::once(receiver).chain(args)),
+                None => make::arg_list(iter::once(receiver)),
+            };
+            replacer(format!("{import}::{method_name}{generics}{arg_list}"));
         }
         Some(())
     }
@@ -218,15 +213,17 @@ fn group_label(candidate: &ImportCandidate) -> GroupLabel {
         }
     }
     .text();
-    GroupLabel(format!("Qualify {}", name))
+    GroupLabel(format!("Qualify {name}"))
 }
 
 fn label(candidate: &ImportCandidate, import: &LocatedImport) -> String {
+    let import_path = &import.import_path;
+
     match candidate {
         ImportCandidate::Path(candidate) if candidate.qualifier.is_none() => {
-            format!("Qualify as `{}`", import.import_path)
+            format!("Qualify as `{import_path}`")
         }
-        _ => format!("Qualify with `{}`", import.import_path),
+        _ => format!("Qualify with `{import_path}`"),
     }
 }
 
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/raw_string.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/raw_string.rs
index dbe8cb7bf031..c9bc25b27a5e 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/raw_string.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/raw_string.rs
@@ -34,13 +34,10 @@ pub(crate) fn make_raw_string(acc: &mut Assists, ctx: &AssistContext<'_>) -> Opt
             let hashes = "#".repeat(required_hashes(&value).max(1));
             if matches!(value, Cow::Borrowed(_)) {
                 // Avoid replacing the whole string to better position the cursor.
-                edit.insert(token.syntax().text_range().start(), format!("r{}", hashes));
+                edit.insert(token.syntax().text_range().start(), format!("r{hashes}"));
                 edit.insert(token.syntax().text_range().end(), hashes);
             } else {
-                edit.replace(
-                    token.syntax().text_range(),
-                    format!("r{}\"{}\"{}", hashes, value, hashes),
-                );
+                edit.replace(token.syntax().text_range(), format!("r{hashes}\"{value}\"{hashes}"));
             }
         },
     )
@@ -83,7 +80,7 @@ pub(crate) fn make_usual_string(acc: &mut Assists, ctx: &AssistContext<'_>) -> O
                 }
             }
 
-            edit.replace(token.syntax().text_range(), format!("\"{}\"", escaped));
+            edit.replace(token.syntax().text_range(), format!("\"{escaped}\""));
         },
     )
 }
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/remove_dbg.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/remove_dbg.rs
index afaa7c933c73..3d9cbff177ba 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/remove_dbg.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/remove_dbg.rs
@@ -102,7 +102,7 @@ pub(crate) fn remove_dbg(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<(
             };
             (
                 macro_call.syntax().text_range(),
-                if wrap { format!("({})", expr) } else { expr.to_string() },
+                if wrap { format!("({expr})") } else { expr.to_string() },
             )
         }
         // dbg!(expr0, expr1, ...)
@@ -127,8 +127,8 @@ mod tests {
     fn check(ra_fixture_before: &str, ra_fixture_after: &str) {
         check_assist(
             remove_dbg,
-            &format!("fn main() {{\n{}\n}}", ra_fixture_before),
-            &format!("fn main() {{\n{}\n}}", ra_fixture_after),
+            &format!("fn main() {{\n{ra_fixture_before}\n}}"),
+            &format!("fn main() {{\n{ra_fixture_after}\n}}"),
         );
     }
 
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/replace_derive_with_manual_impl.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/replace_derive_with_manual_impl.rs
index 9fd5e1886d20..f9ba289ee175 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/replace_derive_with_manual_impl.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/replace_derive_with_manual_impl.rs
@@ -124,7 +124,7 @@ fn add_assist(
 ) -> Option<()> {
     let target = attr.syntax().text_range();
     let annotated_name = adt.name()?;
-    let label = format!("Convert to manual `impl {} for {}`", replace_trait_path, annotated_name);
+    let label = format!("Convert to manual `impl {replace_trait_path} for {annotated_name}`");
 
     acc.add(
         AssistId("replace_derive_with_manual_impl", AssistKind::Refactor),
@@ -158,11 +158,8 @@ fn add_assist(
                         }
                     }
 
-                    builder.insert_snippet(
-                        cap,
-                        insert_pos,
-                        format!("\n\n{}", render_snippet(cap, impl_def.syntax(), cursor)),
-                    )
+                    let rendered = render_snippet(cap, impl_def.syntax(), cursor);
+                    builder.insert_snippet(cap, insert_pos, format!("\n\n{rendered}"))
                 }
             };
         },
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/replace_or_with_or_else.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/replace_or_with_or_else.rs
index 7d91be621013..77382056c183 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/replace_or_with_or_else.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/replace_or_with_or_else.rs
@@ -62,7 +62,7 @@ pub(crate) fn replace_or_with_or_else(acc: &mut Assists, ctx: &AssistContext<'_>
 
     acc.add(
         AssistId("replace_or_with_or_else", AssistKind::RefactorRewrite),
-        format!("Replace {} with {}", name.text(), replace),
+        format!("Replace {name} with {replace}"),
         call.syntax().text_range(),
         |builder| {
             builder.replace(name.syntax().text_range(), replace);
@@ -138,7 +138,7 @@ pub(crate) fn replace_or_else_with_or(acc: &mut Assists, ctx: &AssistContext<'_>
 
     acc.add(
         AssistId("replace_or_else_with_or", AssistKind::RefactorRewrite),
-        format!("Replace {} with {}", name.text(), replace),
+        format!("Replace {name} with {replace}"),
         call.syntax().text_range(),
         |builder| {
             builder.replace(name.syntax().text_range(), replace);
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/replace_turbofish_with_explicit_type.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/replace_turbofish_with_explicit_type.rs
index 521447c26dfb..c177adc7a10d 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/replace_turbofish_with_explicit_type.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/replace_turbofish_with_explicit_type.rs
@@ -79,7 +79,7 @@ pub(crate) fn replace_turbofish_with_explicit_type(
             "Replace turbofish with explicit type",
             TextRange::new(initializer_start, turbofish_range.end()),
             |builder| {
-                builder.insert(ident_range.end(), format!(": {}", returned_type));
+                builder.insert(ident_range.end(), format!(": {returned_type}"));
                 builder.delete(turbofish_range);
             },
         );
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/unnecessary_async.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/unnecessary_async.rs
index d5cd2d551349..043988322533 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/unnecessary_async.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/unnecessary_async.rs
@@ -44,6 +44,12 @@ pub(crate) fn unnecessary_async(acc: &mut Assists, ctx: &AssistContext<'_>) -> O
     if function.body()?.syntax().descendants().find_map(ast::AwaitExpr::cast).is_some() {
         return None;
     }
+    // Do nothing if the method is a member of trait.
+    if let Some(impl_) = function.syntax().ancestors().nth(2).and_then(ast::Impl::cast) {
+        if let Some(_) = impl_.trait_() {
+            return None;
+        }
+    }
 
     // Remove the `async` keyword plus whitespace after it, if any.
     let async_range = {
@@ -254,4 +260,18 @@ pub async fn f(s: &S) { s.f2() }"#,
     fn does_not_apply_when_not_on_prototype() {
         check_assist_not_applicable(unnecessary_async, "pub async fn f() { $0f2() }")
     }
+
+    #[test]
+    fn does_not_apply_on_async_trait_method() {
+        check_assist_not_applicable(
+            unnecessary_async,
+            r#"
+trait Trait {
+    async fn foo();
+}
+impl Trait for () {
+    $0async fn foo() {}
+}"#,
+        );
+    }
 }
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/unwrap_tuple.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/unwrap_tuple.rs
index 25c58d086e97..d09614c51127 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/unwrap_tuple.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/unwrap_tuple.rs
@@ -69,13 +69,13 @@ pub(crate) fn unwrap_tuple(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option
                 for (pat, ty, expr) in
                     itertools::izip!(tuple_pat.fields(), tys.fields(), tuple_init.fields())
                 {
-                    zipped_decls.push_str(&format!("{}let {pat}: {ty} = {expr};\n", indents))
+                    zipped_decls.push_str(&format!("{indents}let {pat}: {ty} = {expr};\n"))
                 }
                 edit.replace(parent.text_range(), zipped_decls.trim());
             } else {
                 let mut zipped_decls = String::new();
                 for (pat, expr) in itertools::izip!(tuple_pat.fields(), tuple_init.fields()) {
-                    zipped_decls.push_str(&format!("{}let {pat} = {expr};\n", indents));
+                    zipped_decls.push_str(&format!("{indents}let {pat} = {expr};\n"));
                 }
                 edit.replace(parent.text_range(), zipped_decls.trim());
             }
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/wrap_return_type_in_result.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/wrap_return_type_in_result.rs
index 83446387db1c..b6c489eb62ee 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/wrap_return_type_in_result.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/wrap_return_type_in_result.rs
@@ -76,11 +76,11 @@ pub(crate) fn wrap_return_type_in_result(acc: &mut Assists, ctx: &AssistContext<
 
             match ctx.config.snippet_cap {
                 Some(cap) => {
-                    let snippet = format!("Result<{}, ${{0:_}}>", type_ref);
+                    let snippet = format!("Result<{type_ref}, ${{0:_}}>");
                     builder.replace_snippet(cap, type_ref.syntax().text_range(), snippet)
                 }
                 None => builder
-                    .replace(type_ref.syntax().text_range(), format!("Result<{}, _>", type_ref)),
+                    .replace(type_ref.syntax().text_range(), format!("Result<{type_ref}, _>")),
             }
         },
     )
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/lib.rs b/src/tools/rust-analyzer/crates/ide-assists/src/lib.rs
index a07318cefad2..387cc6314282 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/lib.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/lib.rs
@@ -120,6 +120,7 @@ mod handlers {
     mod convert_into_to_from;
     mod convert_iter_for_each_to_for;
     mod convert_let_else_to_match;
+    mod convert_match_to_let_else;
     mod convert_tuple_struct_to_named_struct;
     mod convert_named_struct_to_tuple_struct;
     mod convert_to_guarded_return;
@@ -220,6 +221,7 @@ mod handlers {
             convert_iter_for_each_to_for::convert_for_loop_with_for_each,
             convert_let_else_to_match::convert_let_else_to_match,
             convert_named_struct_to_tuple_struct::convert_named_struct_to_tuple_struct,
+            convert_match_to_let_else::convert_match_to_let_else,
             convert_to_guarded_return::convert_to_guarded_return,
             convert_tuple_struct_to_named_struct::convert_tuple_struct_to_named_struct,
             convert_two_arm_bool_match_to_matches_macro::convert_two_arm_bool_match_to_matches_macro,
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/tests.rs b/src/tools/rust-analyzer/crates/ide-assists/src/tests.rs
index f7f2417d0745..92ced27c78ae 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/tests.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/tests.rs
@@ -30,6 +30,7 @@ pub(crate) const TEST_CONFIG: AssistConfig = AssistConfig {
         skip_glob_imports: true,
     },
     prefer_no_std: false,
+    assist_emit_must_use: false,
 };
 
 pub(crate) fn with_single_file(text: &str) -> (RootDatabase, FileId) {
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/tests/generated.rs b/src/tools/rust-analyzer/crates/ide-assists/src/tests/generated.rs
index 2c4000efe0fa..029d169899bb 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/tests/generated.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/tests/generated.rs
@@ -407,6 +407,27 @@ fn main() {
     )
 }
 
+#[test]
+fn doctest_convert_match_to_let_else() {
+    check_doc_test(
+        "convert_match_to_let_else",
+        r#####"
+//- minicore: option
+fn foo(opt: Option<()>) {
+    let val = $0match opt {
+        Some(it) => it,
+        None => return,
+    };
+}
+"#####,
+        r#####"
+fn foo(opt: Option<()>) {
+    let Some(val) = opt else { return };
+}
+"#####,
+    )
+}
+
 #[test]
 fn doctest_convert_named_struct_to_tuple_struct() {
     check_doc_test(
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/utils.rs b/src/tools/rust-analyzer/crates/ide-assists/src/utils.rs
index 38396cd7d7ba..307e67927056 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/utils.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/utils.rs
@@ -189,8 +189,8 @@ pub(crate) fn render_snippet(_cap: SnippetCap, node: &SyntaxNode, cursor: Cursor
     let mut placeholder = cursor.node().to_string();
     escape(&mut placeholder);
     let tab_stop = match cursor {
-        Cursor::Replace(placeholder) => format!("${{0:{}}}", placeholder),
-        Cursor::Before(placeholder) => format!("$0{}", placeholder),
+        Cursor::Replace(placeholder) => format!("${{0:{placeholder}}}"),
+        Cursor::Before(placeholder) => format!("$0{placeholder}"),
     };
 
     let mut buf = node.to_string();
@@ -331,10 +331,14 @@ fn calc_depth(pat: &ast::Pat, depth: usize) -> usize {
 // FIXME: change the new fn checking to a more semantic approach when that's more
 // viable (e.g. we process proc macros, etc)
 // FIXME: this partially overlaps with `find_impl_block_*`
+
+/// `find_struct_impl` looks for impl of a struct, but this also has additional feature
+/// where it takes a list of function names and check if they exist inside impl_, if
+/// even one match is found, it returns None
 pub(crate) fn find_struct_impl(
     ctx: &AssistContext<'_>,
     adt: &ast::Adt,
-    name: &str,
+    names: &[String],
 ) -> Option<Option<ast::Impl>> {
     let db = ctx.db();
     let module = adt.syntax().parent()?;
@@ -362,7 +366,7 @@ pub(crate) fn find_struct_impl(
     });
 
     if let Some(ref impl_blk) = block {
-        if has_fn(impl_blk, name) {
+        if has_any_fn(impl_blk, names) {
             return None;
         }
     }
@@ -370,12 +374,12 @@ pub(crate) fn find_struct_impl(
     Some(block)
 }
 
-fn has_fn(imp: &ast::Impl, rhs_name: &str) -> bool {
+fn has_any_fn(imp: &ast::Impl, names: &[String]) -> bool {
     if let Some(il) = imp.assoc_item_list() {
         for item in il.assoc_items() {
             if let ast::AssocItem::Fn(f) = item {
                 if let Some(name) = f.name() {
-                    if name.text().eq_ignore_ascii_case(rhs_name) {
+                    if names.iter().any(|n| n.eq_ignore_ascii_case(&name.text())) {
                         return true;
                     }
                 }
@@ -535,17 +539,17 @@ impl ReferenceConversion {
             ReferenceConversionType::AsRefSlice => {
                 let type_argument_name =
                     self.ty.type_arguments().next().unwrap().display(db).to_string();
-                format!("&[{}]", type_argument_name)
+                format!("&[{type_argument_name}]")
             }
             ReferenceConversionType::Dereferenced => {
                 let type_argument_name =
                     self.ty.type_arguments().next().unwrap().display(db).to_string();
-                format!("&{}", type_argument_name)
+                format!("&{type_argument_name}")
             }
             ReferenceConversionType::Option => {
                 let type_argument_name =
                     self.ty.type_arguments().next().unwrap().display(db).to_string();
-                format!("Option<&{}>", type_argument_name)
+                format!("Option<&{type_argument_name}>")
             }
             ReferenceConversionType::Result => {
                 let mut type_arguments = self.ty.type_arguments();
@@ -553,19 +557,19 @@ impl ReferenceConversion {
                     type_arguments.next().unwrap().display(db).to_string();
                 let second_type_argument_name =
                     type_arguments.next().unwrap().display(db).to_string();
-                format!("Result<&{}, &{}>", first_type_argument_name, second_type_argument_name)
+                format!("Result<&{first_type_argument_name}, &{second_type_argument_name}>")
             }
         }
     }
 
     pub(crate) fn getter(&self, field_name: String) -> String {
         match self.conversion {
-            ReferenceConversionType::Copy => format!("self.{}", field_name),
+            ReferenceConversionType::Copy => format!("self.{field_name}"),
             ReferenceConversionType::AsRefStr
             | ReferenceConversionType::AsRefSlice
             | ReferenceConversionType::Dereferenced
             | ReferenceConversionType::Option
-            | ReferenceConversionType::Result => format!("self.{}.as_ref()", field_name),
+            | ReferenceConversionType::Result => format!("self.{field_name}.as_ref()"),
         }
     }
 }
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/utils/gen_trait_fn_body.rs b/src/tools/rust-analyzer/crates/ide-assists/src/utils/gen_trait_fn_body.rs
index 7a0c912959a1..6c87e66c134d 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/utils/gen_trait_fn_body.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/utils/gen_trait_fn_body.rs
@@ -41,7 +41,7 @@ fn gen_clone_impl(adt: &ast::Adt, func: &ast::Fn) -> Option<()> {
             let mut arms = vec![];
             for variant in list.variants() {
                 let name = variant.name()?;
-                let variant_name = make::ext::path_from_idents(["Self", &format!("{}", name)])?;
+                let variant_name = make::ext::path_from_idents(["Self", &format!("{name}")])?;
 
                 match variant.field_list() {
                     // => match self { Self::Name { x } => Self::Name { x: x.clone() } }
@@ -70,7 +70,7 @@ fn gen_clone_impl(adt: &ast::Adt, func: &ast::Fn) -> Option<()> {
                         let mut pats = vec![];
                         let mut fields = vec![];
                         for (i, _) in list.fields().enumerate() {
-                            let field_name = format!("arg{}", i);
+                            let field_name = format!("arg{i}");
                             let pat = make::ident_pat(false, false, make::name(&field_name));
                             pats.push(pat.into());
 
@@ -118,7 +118,7 @@ fn gen_clone_impl(adt: &ast::Adt, func: &ast::Fn) -> Option<()> {
                     let mut fields = vec![];
                     for (i, _) in field_list.fields().enumerate() {
                         let f_path = make::expr_path(make::ext::ident_path("self"));
-                        let target = make::expr_field(f_path, &format!("{}", i));
+                        let target = make::expr_field(f_path, &format!("{i}"));
                         fields.push(gen_clone_call(target));
                     }
                     let struct_name = make::expr_path(make::ext::ident_path("Self"));
@@ -151,7 +151,7 @@ fn gen_debug_impl(adt: &ast::Adt, func: &ast::Fn) -> Option<()> {
             let mut arms = vec![];
             for variant in list.variants() {
                 let name = variant.name()?;
-                let variant_name = make::ext::path_from_idents(["Self", &format!("{}", name)])?;
+                let variant_name = make::ext::path_from_idents(["Self", &format!("{name}")])?;
                 let target = make::expr_path(make::ext::ident_path("f"));
 
                 match variant.field_list() {
@@ -159,7 +159,7 @@ fn gen_debug_impl(adt: &ast::Adt, func: &ast::Fn) -> Option<()> {
                         // => f.debug_struct(name)
                         let target = make::expr_path(make::ext::ident_path("f"));
                         let method = make::name_ref("debug_struct");
-                        let struct_name = format!("\"{}\"", name);
+                        let struct_name = format!("\"{name}\"");
                         let args = make::arg_list(Some(make::expr_literal(&struct_name).into()));
                         let mut expr = make::expr_method_call(target, method, args);
 
@@ -173,8 +173,8 @@ fn gen_debug_impl(adt: &ast::Adt, func: &ast::Fn) -> Option<()> {
 
                             // => <expr>.field("field_name", field)
                             let method_name = make::name_ref("field");
-                            let name = make::expr_literal(&(format!("\"{}\"", field_name))).into();
-                            let path = &format!("{}", field_name);
+                            let name = make::expr_literal(&(format!("\"{field_name}\""))).into();
+                            let path = &format!("{field_name}");
                             let path = make::expr_path(make::ext::ident_path(path));
                             let args = make::arg_list(vec![name, path]);
                             expr = make::expr_method_call(expr, method_name, args);
@@ -192,13 +192,13 @@ fn gen_debug_impl(adt: &ast::Adt, func: &ast::Fn) -> Option<()> {
                         // => f.debug_tuple(name)
                         let target = make::expr_path(make::ext::ident_path("f"));
                         let method = make::name_ref("debug_tuple");
-                        let struct_name = format!("\"{}\"", name);
+                        let struct_name = format!("\"{name}\"");
                         let args = make::arg_list(Some(make::expr_literal(&struct_name).into()));
                         let mut expr = make::expr_method_call(target, method, args);
 
                         let mut pats = vec![];
                         for (i, _) in list.fields().enumerate() {
-                            let name = format!("arg{}", i);
+                            let name = format!("arg{i}");
 
                             // create a field pattern for use in `MyStruct(fields..)`
                             let field_name = make::name(&name);
@@ -222,7 +222,7 @@ fn gen_debug_impl(adt: &ast::Adt, func: &ast::Fn) -> Option<()> {
                         arms.push(make::match_arm(Some(pat.into()), None, expr));
                     }
                     None => {
-                        let fmt_string = make::expr_literal(&(format!("\"{}\"", name))).into();
+                        let fmt_string = make::expr_literal(&(format!("\"{name}\""))).into();
                         let args = make::arg_list([target, fmt_string]);
                         let macro_name = make::expr_path(make::ext::ident_path("write"));
                         let macro_call = make::expr_macro_call(macro_name, args);
@@ -244,7 +244,7 @@ fn gen_debug_impl(adt: &ast::Adt, func: &ast::Fn) -> Option<()> {
         }
 
         ast::Adt::Struct(strukt) => {
-            let name = format!("\"{}\"", annotated_name);
+            let name = format!("\"{annotated_name}\"");
             let args = make::arg_list(Some(make::expr_literal(&name).into()));
             let target = make::expr_path(make::ext::ident_path("f"));
 
@@ -258,10 +258,10 @@ fn gen_debug_impl(adt: &ast::Adt, func: &ast::Fn) -> Option<()> {
                     let mut expr = make::expr_method_call(target, method, args);
                     for field in field_list.fields() {
                         let name = field.name()?;
-                        let f_name = make::expr_literal(&(format!("\"{}\"", name))).into();
+                        let f_name = make::expr_literal(&(format!("\"{name}\""))).into();
                         let f_path = make::expr_path(make::ext::ident_path("self"));
                         let f_path = make::expr_ref(f_path, false);
-                        let f_path = make::expr_field(f_path, &format!("{}", name));
+                        let f_path = make::expr_field(f_path, &format!("{name}"));
                         let args = make::arg_list([f_name, f_path]);
                         expr = make::expr_method_call(expr, make::name_ref("field"), args);
                     }
@@ -275,7 +275,7 @@ fn gen_debug_impl(adt: &ast::Adt, func: &ast::Fn) -> Option<()> {
                     for (i, _) in field_list.fields().enumerate() {
                         let f_path = make::expr_path(make::ext::ident_path("self"));
                         let f_path = make::expr_ref(f_path, false);
-                        let f_path = make::expr_field(f_path, &format!("{}", i));
+                        let f_path = make::expr_field(f_path, &format!("{i}"));
                         let method = make::name_ref("field");
                         expr = make::expr_method_call(expr, method, make::arg_list(Some(f_path)));
                     }
@@ -379,7 +379,7 @@ fn gen_hash_impl(adt: &ast::Adt, func: &ast::Fn) -> Option<()> {
                 let mut stmts = vec![];
                 for (i, _) in field_list.fields().enumerate() {
                     let base = make::expr_path(make::ext::ident_path("self"));
-                    let target = make::expr_field(base, &format!("{}", i));
+                    let target = make::expr_field(base, &format!("{i}"));
                     stmts.push(gen_hash_call(target));
                 }
                 make::block_expr(stmts, None).indent(ast::edit::IndentLevel(1))
@@ -453,10 +453,10 @@ fn gen_partial_eq(adt: &ast::Adt, func: &ast::Fn) -> Option<()> {
                         for field in list.fields() {
                             let field_name = field.name()?.to_string();
 
-                            let l_name = &format!("l_{}", field_name);
+                            let l_name = &format!("l_{field_name}");
                             l_fields.push(gen_record_pat_field(&field_name, l_name));
 
-                            let r_name = &format!("r_{}", field_name);
+                            let r_name = &format!("r_{field_name}");
                             r_fields.push(gen_record_pat_field(&field_name, r_name));
 
                             let lhs = make::expr_path(make::ext::ident_path(l_name));
@@ -484,12 +484,12 @@ fn gen_partial_eq(adt: &ast::Adt, func: &ast::Fn) -> Option<()> {
                         let mut r_fields = vec![];
 
                         for (i, _) in list.fields().enumerate() {
-                            let field_name = format!("{}", i);
+                            let field_name = format!("{i}");
 
-                            let l_name = format!("l{}", field_name);
+                            let l_name = format!("l{field_name}");
                             l_fields.push(gen_tuple_field(&l_name));
 
-                            let r_name = format!("r{}", field_name);
+                            let r_name = format!("r{field_name}");
                             r_fields.push(gen_tuple_field(&r_name));
 
                             let lhs = make::expr_path(make::ext::ident_path(&l_name));
@@ -548,7 +548,7 @@ fn gen_partial_eq(adt: &ast::Adt, func: &ast::Fn) -> Option<()> {
             Some(ast::FieldList::TupleFieldList(field_list)) => {
                 let mut expr = None;
                 for (i, _) in field_list.fields().enumerate() {
-                    let idx = format!("{}", i);
+                    let idx = format!("{i}");
                     let lhs = make::expr_path(make::ext::ident_path("self"));
                     let lhs = make::expr_field(lhs, &idx);
                     let rhs = make::expr_path(make::ext::ident_path("other"));
@@ -628,7 +628,7 @@ fn gen_partial_ord(adt: &ast::Adt, func: &ast::Fn) -> Option<()> {
             Some(ast::FieldList::TupleFieldList(field_list)) => {
                 let mut exprs = vec![];
                 for (i, _) in field_list.fields().enumerate() {
-                    let idx = format!("{}", i);
+                    let idx = format!("{i}");
                     let lhs = make::expr_path(make::ext::ident_path("self"));
                     let lhs = make::expr_field(lhs, &idx);
                     let rhs = make::expr_path(make::ext::ident_path("other"));
diff --git a/src/tools/rust-analyzer/crates/ide-completion/src/completions/postfix.rs b/src/tools/rust-analyzer/crates/ide-completion/src/completions/postfix.rs
index 9a891cea2d45..b9bd47f7da50 100644
--- a/src/tools/rust-analyzer/crates/ide-completion/src/completions/postfix.rs
+++ b/src/tools/rust-analyzer/crates/ide-completion/src/completions/postfix.rs
@@ -69,10 +69,6 @@ pub(crate) fn complete_postfix(
         }
     }
 
-    if !ctx.config.snippets.is_empty() {
-        add_custom_postfix_completions(acc, ctx, &postfix_snippet, &receiver_text);
-    }
-
     let try_enum = TryEnum::from_ty(&ctx.sema, &receiver_ty.strip_references());
     if let Some(try_enum) = &try_enum {
         match try_enum {
@@ -140,6 +136,10 @@ pub(crate) fn complete_postfix(
         None => return,
     };
 
+    if !ctx.config.snippets.is_empty() {
+        add_custom_postfix_completions(acc, ctx, &postfix_snippet, &receiver_text);
+    }
+
     match try_enum {
         Some(try_enum) => match try_enum {
             TryEnum::Result => {
@@ -613,4 +613,25 @@ fn main() {
             r#"fn main() { log::error!("{}", 2+2) }"#,
         );
     }
+
+    #[test]
+    fn postfix_custom_snippets_completion_for_references() {
+        check_edit_with_config(
+            CompletionConfig {
+                snippets: vec![Snippet::new(
+                    &[],
+                    &["ok".into()],
+                    &["Ok(${receiver})".into()],
+                    "",
+                    &[],
+                    crate::SnippetScope::Expr,
+                )
+                .unwrap()],
+                ..TEST_CONFIG
+            },
+            "ok",
+            r#"fn main() { &&42.$0 }"#,
+            r#"fn main() { Ok(&&42) }"#,
+        );
+    }
 }
diff --git a/src/tools/rust-analyzer/crates/ide-db/src/search.rs b/src/tools/rust-analyzer/crates/ide-db/src/search.rs
index 82b85f2fa5ed..aa5d7e9beb54 100644
--- a/src/tools/rust-analyzer/crates/ide-db/src/search.rs
+++ b/src/tools/rust-analyzer/crates/ide-db/src/search.rs
@@ -446,33 +446,47 @@ impl<'a> FindUsages<'a> {
             })
         }
 
-        // FIXME: There should be optimization potential here
-        // Currently we try to descend everything we find which
-        // means we call `Semantics::descend_into_macros` on
-        // every textual hit. That function is notoriously
-        // expensive even for things that do not get down mapped
-        // into macros.
+        let find_nodes = move |name: &str, node: &syntax::SyntaxNode, offset: TextSize| {
+            node.token_at_offset(offset).find(|it| it.text() == name).map(|token| {
+                // FIXME: There should be optimization potential here
+                // Currently we try to descend everything we find which
+                // means we call `Semantics::descend_into_macros` on
+                // every textual hit. That function is notoriously
+                // expensive even for things that do not get down mapped
+                // into macros.
+                sema.descend_into_macros(token).into_iter().filter_map(|it| it.parent())
+            })
+        };
+
         for (text, file_id, search_range) in scope_files(sema, &search_scope) {
             let tree = Lazy::new(move || sema.parse(file_id).syntax().clone());
 
             // Search for occurrences of the items name
             for offset in match_indices(&text, finder, search_range) {
-                for name in sema.find_nodes_at_offset_with_descend(&tree, offset) {
-                    if match name {
-                        ast::NameLike::NameRef(name_ref) => self.found_name_ref(&name_ref, sink),
-                        ast::NameLike::Name(name) => self.found_name(&name, sink),
-                        ast::NameLike::Lifetime(lifetime) => self.found_lifetime(&lifetime, sink),
-                    } {
-                        return;
+                if let Some(iter) = find_nodes(name, &tree, offset) {
+                    for name in iter.filter_map(ast::NameLike::cast) {
+                        if match name {
+                            ast::NameLike::NameRef(name_ref) => {
+                                self.found_name_ref(&name_ref, sink)
+                            }
+                            ast::NameLike::Name(name) => self.found_name(&name, sink),
+                            ast::NameLike::Lifetime(lifetime) => {
+                                self.found_lifetime(&lifetime, sink)
+                            }
+                        } {
+                            return;
+                        }
                     }
                 }
             }
             // Search for occurrences of the `Self` referring to our type
             if let Some((self_ty, finder)) = &include_self_kw_refs {
                 for offset in match_indices(&text, finder, search_range) {
-                    for name_ref in sema.find_nodes_at_offset_with_descend(&tree, offset) {
-                        if self.found_self_ty_name_ref(self_ty, &name_ref, sink) {
-                            return;
+                    if let Some(iter) = find_nodes("Self", &tree, offset) {
+                        for name_ref in iter.filter_map(ast::NameRef::cast) {
+                            if self.found_self_ty_name_ref(self_ty, &name_ref, sink) {
+                                return;
+                            }
                         }
                     }
                 }
@@ -493,17 +507,21 @@ impl<'a> FindUsages<'a> {
                     let tree = Lazy::new(move || sema.parse(file_id).syntax().clone());
 
                     for offset in match_indices(&text, finder, search_range) {
-                        for name_ref in sema.find_nodes_at_offset_with_descend(&tree, offset) {
-                            if self.found_name_ref(&name_ref, sink) {
-                                return;
+                        if let Some(iter) = find_nodes("super", &tree, offset) {
+                            for name_ref in iter.filter_map(ast::NameRef::cast) {
+                                if self.found_name_ref(&name_ref, sink) {
+                                    return;
+                                }
                             }
                         }
                     }
                     if let Some(finder) = &is_crate_root {
                         for offset in match_indices(&text, finder, search_range) {
-                            for name_ref in sema.find_nodes_at_offset_with_descend(&tree, offset) {
-                                if self.found_name_ref(&name_ref, sink) {
-                                    return;
+                            if let Some(iter) = find_nodes("crate", &tree, offset) {
+                                for name_ref in iter.filter_map(ast::NameRef::cast) {
+                                    if self.found_name_ref(&name_ref, sink) {
+                                        return;
+                                    }
                                 }
                             }
                         }
@@ -544,9 +562,11 @@ impl<'a> FindUsages<'a> {
                 let finder = &Finder::new("self");
 
                 for offset in match_indices(&text, finder, search_range) {
-                    for name_ref in sema.find_nodes_at_offset_with_descend(&tree, offset) {
-                        if self.found_self_module_name_ref(&name_ref, sink) {
-                            return;
+                    if let Some(iter) = find_nodes("self", &tree, offset) {
+                        for name_ref in iter.filter_map(ast::NameRef::cast) {
+                            if self.found_self_module_name_ref(&name_ref, sink) {
+                                return;
+                            }
                         }
                     }
                 }
diff --git a/src/tools/rust-analyzer/crates/ide-diagnostics/src/handlers/incorrect_try_expr.rs b/src/tools/rust-analyzer/crates/ide-diagnostics/src/handlers/incorrect_try_expr.rs
deleted file mode 100644
index 085d8d32598a..000000000000
--- a/src/tools/rust-analyzer/crates/ide-diagnostics/src/handlers/incorrect_try_expr.rs
+++ /dev/null
@@ -1,37 +0,0 @@
-use hir::InFile;
-
-use crate::{Diagnostic, DiagnosticsContext};
-
-// Diagnostic: incorrect-try-target
-//
-// This diagnostic is triggered if a question mark operator was used in a context where it is not applicable.
-pub(crate) fn incorrect_try_expr(
-    ctx: &DiagnosticsContext<'_>,
-    d: &hir::IncorrectTryExpr,
-) -> Diagnostic {
-    Diagnostic::new(
-        "incorrect-try-target",
-        format!("the return type of the containing function does not implement `FromResidual`"),
-        ctx.sema
-            .diagnostics_display_range(InFile::new(d.expr.file_id, d.expr.value.clone().into()))
-            .range,
-    )
-}
-
-#[cfg(test)]
-mod tests {
-    use crate::tests::check_diagnostics;
-
-    #[test]
-    fn try_ops_diag() {
-        check_diagnostics(
-            r#"
-//- minicore: try
-fn test() {
-    core::ops::ControlFlow::<u32, f32>::Continue(1.0)?;
- // ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: the return type of the containing function does not implement `FromResidual`
-}
-"#,
-        );
-    }
-}
diff --git a/src/tools/rust-analyzer/crates/ide-diagnostics/src/handlers/not_implemented.rs b/src/tools/rust-analyzer/crates/ide-diagnostics/src/handlers/not_implemented.rs
deleted file mode 100644
index 3bf6a4232298..000000000000
--- a/src/tools/rust-analyzer/crates/ide-diagnostics/src/handlers/not_implemented.rs
+++ /dev/null
@@ -1,35 +0,0 @@
-use hir::{db::DefDatabase, HirDisplay};
-
-use crate::{Diagnostic, DiagnosticsContext};
-
-// Diagnostic: not-implemented
-//
-// This diagnostic is triggered if a type doesn't implement a necessary trait.
-pub(crate) fn not_implemented(ctx: &DiagnosticsContext<'_>, d: &hir::NotImplemented) -> Diagnostic {
-    Diagnostic::new(
-        "not-implemented",
-        format!(
-            "the trait `{}` is not implemented for `{}`",
-            ctx.sema.db.trait_data(d.trait_).name,
-            d.ty.display(ctx.sema.db)
-        ),
-        ctx.sema.diagnostics_display_range(d.expr.clone().map(|it| it.into())).range,
-    )
-}
-
-#[cfg(test)]
-mod tests {
-    use crate::tests::check_diagnostics;
-
-    #[test]
-    fn missing_try_impl() {
-        check_diagnostics(
-            r#"
-//- minicore: try
-fn main() {
-    ()?;
-} //^^ error: the trait `Try` is not implemented for `()`
-"#,
-        )
-    }
-}
diff --git a/src/tools/rust-analyzer/crates/ide-diagnostics/src/lib.rs b/src/tools/rust-analyzer/crates/ide-diagnostics/src/lib.rs
index 4577072149a7..ae299f058414 100644
--- a/src/tools/rust-analyzer/crates/ide-diagnostics/src/lib.rs
+++ b/src/tools/rust-analyzer/crates/ide-diagnostics/src/lib.rs
@@ -29,7 +29,6 @@ mod handlers {
     pub(crate) mod break_outside_of_loop;
     pub(crate) mod inactive_code;
     pub(crate) mod incorrect_case;
-    pub(crate) mod incorrect_try_expr;
     pub(crate) mod invalid_derive_target;
     pub(crate) mod macro_error;
     pub(crate) mod malformed_derive;
@@ -37,7 +36,6 @@ mod handlers {
     pub(crate) mod missing_fields;
     pub(crate) mod missing_match_arms;
     pub(crate) mod missing_unsafe;
-    pub(crate) mod not_implemented;
     pub(crate) mod no_such_field;
     pub(crate) mod replace_filter_map_next_with_find_map;
     pub(crate) mod type_mismatch;
@@ -227,14 +225,12 @@ pub fn diagnostics(
         let d = match diag {
             AnyDiagnostic::BreakOutsideOfLoop(d) => handlers::break_outside_of_loop::break_outside_of_loop(&ctx, &d),
             AnyDiagnostic::IncorrectCase(d) => handlers::incorrect_case::incorrect_case(&ctx, &d),
-            AnyDiagnostic::IncorrectTryExpr(d) => handlers::incorrect_try_expr::incorrect_try_expr(&ctx, &d),
             AnyDiagnostic::MacroError(d) => handlers::macro_error::macro_error(&ctx, &d),
             AnyDiagnostic::MalformedDerive(d) => handlers::malformed_derive::malformed_derive(&ctx, &d),
             AnyDiagnostic::MismatchedArgCount(d) => handlers::mismatched_arg_count::mismatched_arg_count(&ctx, &d),
             AnyDiagnostic::MissingFields(d) => handlers::missing_fields::missing_fields(&ctx, &d),
             AnyDiagnostic::MissingMatchArms(d) => handlers::missing_match_arms::missing_match_arms(&ctx, &d),
             AnyDiagnostic::MissingUnsafe(d) => handlers::missing_unsafe::missing_unsafe(&ctx, &d),
-            AnyDiagnostic::NotImplemented(d) => handlers::not_implemented::not_implemented(&ctx, &d),
             AnyDiagnostic::NoSuchField(d) => handlers::no_such_field::no_such_field(&ctx, &d),
             AnyDiagnostic::ReplaceFilterMapNextWithFindMap(d) => handlers::replace_filter_map_next_with_find_map::replace_filter_map_next_with_find_map(&ctx, &d),
             AnyDiagnostic::TypeMismatch(d) => handlers::type_mismatch::type_mismatch(&ctx, &d),
diff --git a/src/tools/rust-analyzer/crates/ide/src/goto_definition.rs b/src/tools/rust-analyzer/crates/ide/src/goto_definition.rs
index d0be1b3f4047..f97c67b144ac 100644
--- a/src/tools/rust-analyzer/crates/ide/src/goto_definition.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/goto_definition.rs
@@ -1834,4 +1834,86 @@ fn f() {
 "#,
         );
     }
+
+    #[test]
+    fn goto_bin_op_multiple_impl() {
+        check(
+            r#"
+//- minicore: add
+struct S;
+impl core::ops::Add for S {
+    fn add(
+     //^^^
+    ) {}
+}
+impl core::ops::Add<usize> for S {
+    fn add(
+    ) {}
+}
+
+fn f() {
+    S +$0 S
+}
+"#,
+        );
+
+        check(
+            r#"
+//- minicore: add
+struct S;
+impl core::ops::Add for S {
+    fn add(
+    ) {}
+}
+impl core::ops::Add<usize> for S {
+    fn add(
+     //^^^
+    ) {}
+}
+
+fn f() {
+    S +$0 0usize
+}
+"#,
+        );
+    }
+
+    #[test]
+    fn path_call_multiple_trait_impl() {
+        check(
+            r#"
+trait Trait<T> {
+    fn f(_: T);
+}
+impl Trait<i32> for usize {
+    fn f(_: i32) {}
+     //^
+}
+impl Trait<i64> for usize {
+    fn f(_: i64) {}
+}
+fn main() {
+    usize::f$0(0i32);
+}
+"#,
+        );
+
+        check(
+            r#"
+trait Trait<T> {
+    fn f(_: T);
+}
+impl Trait<i32> for usize {
+    fn f(_: i32) {}
+}
+impl Trait<i64> for usize {
+    fn f(_: i64) {}
+     //^
+}
+fn main() {
+    usize::f$0(0i64);
+}
+"#,
+        )
+    }
 }
diff --git a/src/tools/rust-analyzer/crates/ide/src/hover/tests.rs b/src/tools/rust-analyzer/crates/ide/src/hover/tests.rs
index 5cab017a58db..eb997e6fef83 100644
--- a/src/tools/rust-analyzer/crates/ide/src/hover/tests.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/hover/tests.rs
@@ -4913,22 +4913,6 @@ fn foo() -> NotResult<(), Short> {
                 ```
             "#]],
     );
-    check_hover_range(
-        r#"
-//- minicore: try
-use core::ops::ControlFlow;
-fn foo() -> ControlFlow<()> {
-    $0ControlFlow::Break(())?$0;
-    ControlFlow::Continue(())
-}
-"#,
-        expect![[r#"
-            ```text
-            Try Target Type: ControlFlow<(), {unknown}>
-            Propagated as:          ControlFlow<(), ()>
-            ```
-        "#]],
-    );
 }
 
 #[test]
@@ -4944,9 +4928,9 @@ fn foo() -> Option<()> {
 }
 "#,
         expect![[r#"
-            ```rust
-            i32
-            ```"#]],
+                ```rust
+                <Option<i32> as Try>::Output
+                ```"#]],
     );
 }
 
diff --git a/src/tools/rust-analyzer/crates/ide/src/lib.rs b/src/tools/rust-analyzer/crates/ide/src/lib.rs
index 77fe0dbf5565..416817ca0b42 100644
--- a/src/tools/rust-analyzer/crates/ide/src/lib.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/lib.rs
@@ -482,8 +482,18 @@ impl Analysis {
     }
 
     /// Returns crates this file belongs too.
-    pub fn crate_for(&self, file_id: FileId) -> Cancellable<Vec<CrateId>> {
-        self.with_db(|db| parent_module::crate_for(db, file_id))
+    pub fn crates_for(&self, file_id: FileId) -> Cancellable<Vec<CrateId>> {
+        self.with_db(|db| parent_module::crates_for(db, file_id))
+    }
+
+    /// Returns crates this file belongs too.
+    pub fn transitive_rev_deps(&self, crate_id: CrateId) -> Cancellable<Vec<CrateId>> {
+        self.with_db(|db| db.crate_graph().transitive_rev_deps(crate_id).collect())
+    }
+
+    /// Returns crates this file *might* belong too.
+    pub fn relevant_crates_for(&self, file_id: FileId) -> Cancellable<Vec<CrateId>> {
+        self.with_db(|db| db.relevant_crates(file_id).iter().copied().collect())
     }
 
     /// Returns the edition of the given crate.
diff --git a/src/tools/rust-analyzer/crates/ide/src/moniker.rs b/src/tools/rust-analyzer/crates/ide/src/moniker.rs
index 852a8fd83761..07d117aff10b 100644
--- a/src/tools/rust-analyzer/crates/ide/src/moniker.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/moniker.rs
@@ -73,8 +73,8 @@ impl MonikerResult {
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct PackageInformation {
     pub name: String,
-    pub repo: String,
-    pub version: String,
+    pub repo: Option<String>,
+    pub version: Option<String>,
 }
 
 pub(crate) fn crate_for_file(db: &RootDatabase, file_id: FileId) -> Option<Crate> {
@@ -256,18 +256,18 @@ pub(crate) fn def_to_moniker(
             let (name, repo, version) = match krate.origin(db) {
                 CrateOrigin::CratesIo { repo, name } => (
                     name.unwrap_or(krate.display_name(db)?.canonical_name().to_string()),
-                    repo?,
-                    krate.version(db)?,
+                    repo,
+                    krate.version(db),
                 ),
                 CrateOrigin::Lang(lang) => (
                     krate.display_name(db)?.canonical_name().to_string(),
-                    "https://github.com/rust-lang/rust/".to_string(),
-                    match lang {
+                    Some("https://github.com/rust-lang/rust/".to_string()),
+                    Some(match lang {
                         LangCrateOrigin::Other => {
                             "https://github.com/rust-lang/rust/library/".into()
                         }
                         lang => format!("https://github.com/rust-lang/rust/library/{lang}",),
-                    },
+                    }),
                 ),
             };
             PackageInformation { name, repo, version }
@@ -315,7 +315,7 @@ pub mod module {
 }
 "#,
             "foo::module::func",
-            r#"PackageInformation { name: "foo", repo: "https://a.b/foo.git", version: "0.1.0" }"#,
+            r#"PackageInformation { name: "foo", repo: Some("https://a.b/foo.git"), version: Some("0.1.0") }"#,
             MonikerKind::Import,
         );
         check_moniker(
@@ -331,7 +331,7 @@ pub mod module {
 }
 "#,
             "foo::module::func",
-            r#"PackageInformation { name: "foo", repo: "https://a.b/foo.git", version: "0.1.0" }"#,
+            r#"PackageInformation { name: "foo", repo: Some("https://a.b/foo.git"), version: Some("0.1.0") }"#,
             MonikerKind::Export,
         );
     }
@@ -348,7 +348,7 @@ pub mod module {
 }
 "#,
             "foo::module::MyTrait::func",
-            r#"PackageInformation { name: "foo", repo: "https://a.b/foo.git", version: "0.1.0" }"#,
+            r#"PackageInformation { name: "foo", repo: Some("https://a.b/foo.git"), version: Some("0.1.0") }"#,
             MonikerKind::Export,
         );
     }
@@ -365,7 +365,7 @@ pub mod module {
 }
 "#,
             "foo::module::MyTrait::MY_CONST",
-            r#"PackageInformation { name: "foo", repo: "https://a.b/foo.git", version: "0.1.0" }"#,
+            r#"PackageInformation { name: "foo", repo: Some("https://a.b/foo.git"), version: Some("0.1.0") }"#,
             MonikerKind::Export,
         );
     }
@@ -382,7 +382,7 @@ pub mod module {
 }
 "#,
             "foo::module::MyTrait::MyType",
-            r#"PackageInformation { name: "foo", repo: "https://a.b/foo.git", version: "0.1.0" }"#,
+            r#"PackageInformation { name: "foo", repo: Some("https://a.b/foo.git"), version: Some("0.1.0") }"#,
             MonikerKind::Export,
         );
     }
@@ -405,7 +405,7 @@ pub mod module {
 }
 "#,
             "foo::module::MyStruct::MyTrait::func",
-            r#"PackageInformation { name: "foo", repo: "https://a.b/foo.git", version: "0.1.0" }"#,
+            r#"PackageInformation { name: "foo", repo: Some("https://a.b/foo.git"), version: Some("0.1.0") }"#,
             MonikerKind::Export,
         );
     }
@@ -425,7 +425,7 @@ pub struct St {
 }
 "#,
             "foo::St::a",
-            r#"PackageInformation { name: "foo", repo: "https://a.b/foo.git", version: "0.1.0" }"#,
+            r#"PackageInformation { name: "foo", repo: Some("https://a.b/foo.git"), version: Some("0.1.0") }"#,
             MonikerKind::Import,
         );
     }
diff --git a/src/tools/rust-analyzer/crates/ide/src/parent_module.rs b/src/tools/rust-analyzer/crates/ide/src/parent_module.rs
index 8f3cc86873f5..506f9452cf19 100644
--- a/src/tools/rust-analyzer/crates/ide/src/parent_module.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/parent_module.rs
@@ -1,6 +1,6 @@
-use hir::Semantics;
+use hir::{db::DefDatabase, Semantics};
 use ide_db::{
-    base_db::{CrateId, FileId, FilePosition},
+    base_db::{CrateId, FileId, FileLoader, FilePosition},
     RootDatabase,
 };
 use itertools::Itertools;
@@ -55,9 +55,13 @@ pub(crate) fn parent_module(db: &RootDatabase, position: FilePosition) -> Vec<Na
 }
 
 /// Returns `Vec` for the same reason as `parent_module`
-pub(crate) fn crate_for(db: &RootDatabase, file_id: FileId) -> Vec<CrateId> {
-    let sema = Semantics::new(db);
-    sema.to_module_defs(file_id).map(|module| module.krate().into()).unique().collect()
+pub(crate) fn crates_for(db: &RootDatabase, file_id: FileId) -> Vec<CrateId> {
+    db.relevant_crates(file_id)
+        .iter()
+        .copied()
+        .filter(|&crate_id| db.crate_def_map(crate_id).modules_for_file(file_id).next().is_some())
+        .sorted()
+        .collect()
 }
 
 #[cfg(test)]
@@ -147,7 +151,7 @@ $0
 mod foo;
 "#,
         );
-        assert_eq!(analysis.crate_for(file_id).unwrap().len(), 1);
+        assert_eq!(analysis.crates_for(file_id).unwrap().len(), 1);
     }
 
     #[test]
@@ -162,6 +166,6 @@ mod baz;
 mod baz;
 "#,
         );
-        assert_eq!(analysis.crate_for(file_id).unwrap().len(), 2);
+        assert_eq!(analysis.crates_for(file_id).unwrap().len(), 2);
     }
 }
diff --git a/src/tools/rust-analyzer/crates/ide/src/rename.rs b/src/tools/rust-analyzer/crates/ide/src/rename.rs
index fe44856dcad2..b4df0437050f 100644
--- a/src/tools/rust-analyzer/crates/ide/src/rename.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/rename.rs
@@ -40,7 +40,9 @@ pub(crate) fn prepare_rename(
             if def.range_for_rename(&sema).is_none() {
                 bail!("No references found at position")
             }
-            let frange = sema.original_range(name_like.syntax());
+            let Some(frange) = sema.original_range_opt(name_like.syntax()) else {
+                bail!("No references found at position");
+            };
 
             always!(
                 frange.range.contains_inclusive(position.offset)
@@ -51,7 +53,7 @@ pub(crate) fn prepare_rename(
         .reduce(|acc, cur| match (acc, cur) {
             // ensure all ranges are the same
             (Ok(acc_inner), Ok(cur_inner)) if acc_inner == cur_inner => Ok(acc_inner),
-            (Err(e), _) => Err(e),
+            (e @ Err(_), _) | (_, e @ Err(_)) => e,
             _ => bail!("inconsistent text range"),
         });
 
@@ -2249,4 +2251,33 @@ fn foo((bar | bar | bar): ()) {
 "#,
         );
     }
+
+    #[test]
+    fn regression_13498() {
+        check(
+            "Testing",
+            r"
+mod foo {
+    pub struct Test$0;
+}
+
+use foo::Test as Tester;
+
+fn main() {
+    let t = Tester;
+}
+",
+            r"
+mod foo {
+    pub struct Testing;
+}
+
+use foo::Testing as Tester;
+
+fn main() {
+    let t = Tester;
+}
+",
+        )
+    }
 }
diff --git a/src/tools/rust-analyzer/crates/ide/src/signature_help.rs b/src/tools/rust-analyzer/crates/ide/src/signature_help.rs
index fedc1a435827..7486b20293a6 100644
--- a/src/tools/rust-analyzer/crates/ide/src/signature_help.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/signature_help.rs
@@ -149,7 +149,7 @@ fn signature_help_for_call(
                 variant.name(db)
             );
         }
-        hir::CallableKind::Closure | hir::CallableKind::FnPtr => (),
+        hir::CallableKind::Closure | hir::CallableKind::FnPtr | hir::CallableKind::Other => (),
     }
 
     res.signature.push('(');
@@ -189,9 +189,10 @@ fn signature_help_for_call(
         hir::CallableKind::Function(func) if callable.return_type().contains_unknown() => {
             render(func.ret_type(db))
         }
-        hir::CallableKind::Function(_) | hir::CallableKind::Closure | hir::CallableKind::FnPtr => {
-            render(callable.return_type())
-        }
+        hir::CallableKind::Function(_)
+        | hir::CallableKind::Closure
+        | hir::CallableKind::FnPtr
+        | hir::CallableKind::Other => render(callable.return_type()),
         hir::CallableKind::TupleStruct(_) | hir::CallableKind::TupleEnumVariant(_) => {}
     }
     Some(res)
@@ -387,10 +388,9 @@ mod tests {
     }
 
     fn check(ra_fixture: &str, expect: Expect) {
-        // Implicitly add `Sized` to avoid noisy `T: ?Sized` in the results.
         let fixture = format!(
             r#"
-#[lang = "sized"] trait Sized {{}}
+//- minicore: sized, fn
 {ra_fixture}
             "#
         );
@@ -1331,4 +1331,19 @@ fn f() {
             "#]],
         );
     }
+
+    #[test]
+    fn help_for_generic_call() {
+        check(
+            r#"
+fn f<F: FnOnce(u8, u16) -> i32>(f: F) {
+    f($0)
+}
+"#,
+            expect![[r#"
+                (u8, u16) -> i32
+                 ^^  ---
+            "#]],
+        );
+    }
 }
diff --git a/src/tools/rust-analyzer/crates/ide/src/static_index.rs b/src/tools/rust-analyzer/crates/ide/src/static_index.rs
index 9e5eb909508f..27ad1a948d13 100644
--- a/src/tools/rust-analyzer/crates/ide/src/static_index.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/static_index.rs
@@ -210,9 +210,7 @@ fn get_definition(sema: &Semantics<'_, RootDatabase>, token: SyntaxToken) -> Opt
         let def = IdentClass::classify_token(sema, &token).map(IdentClass::definitions_no_ops);
         if let Some(&[x]) = def.as_deref() {
             return Some(x);
-        } else {
-            continue;
-        };
+        }
     }
     None
 }
diff --git a/src/tools/rust-analyzer/crates/ide/src/status.rs b/src/tools/rust-analyzer/crates/ide/src/status.rs
index f4d0387440d4..20810c25b3e8 100644
--- a/src/tools/rust-analyzer/crates/ide/src/status.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/status.rs
@@ -45,7 +45,7 @@ pub(crate) fn status(db: &RootDatabase, file_id: Option<FileId>) -> String {
 
     if let Some(file_id) = file_id {
         format_to!(buf, "\nFile info:\n");
-        let crates = crate::parent_module::crate_for(db, file_id);
+        let crates = crate::parent_module::crates_for(db, file_id);
         if crates.is_empty() {
             format_to!(buf, "Does not belong to any crate");
         }
diff --git a/src/tools/rust-analyzer/crates/project-model/Cargo.toml b/src/tools/rust-analyzer/crates/project-model/Cargo.toml
index 6fd7c3166f82..cf9868740cb0 100644
--- a/src/tools/rust-analyzer/crates/project-model/Cargo.toml
+++ b/src/tools/rust-analyzer/crates/project-model/Cargo.toml
@@ -17,7 +17,6 @@ semver = "1.0.14"
 serde = { version = "1.0.137", features = ["derive"] }
 serde_json = "1.0.86"
 anyhow = "1.0.62"
-expect-test = "1.4.0"
 la-arena = { version = "0.3.0", path = "../../lib/la-arena" }
 
 cfg = { path = "../cfg", version = "0.0.0" }
@@ -26,3 +25,6 @@ toolchain = { path = "../toolchain", version = "0.0.0" }
 paths = { path = "../paths", version = "0.0.0" }
 stdx = { path = "../stdx", version = "0.0.0" }
 profile = { path = "../profile", version = "0.0.0" }
+
+[dev-dependencies]
+expect-test = "1.4.0"
diff --git a/src/tools/rust-analyzer/crates/project-model/src/build_scripts.rs b/src/tools/rust-analyzer/crates/project-model/src/build_scripts.rs
index d9f09c034956..a26a7c57acfc 100644
--- a/src/tools/rust-analyzer/crates/project-model/src/build_scripts.rs
+++ b/src/tools/rust-analyzer/crates/project-model/src/build_scripts.rs
@@ -6,7 +6,12 @@
 //! This module implements this second part. We use "build script" terminology
 //! here, but it covers procedural macros as well.
 
-use std::{cell::RefCell, io, path::PathBuf, process::Command};
+use std::{
+    cell::RefCell,
+    io, mem,
+    path::{self, PathBuf},
+    process::Command,
+};
 
 use cargo_metadata::{camino::Utf8Path, Message};
 use la_arena::ArenaMap;
@@ -15,11 +20,14 @@ use rustc_hash::FxHashMap;
 use semver::Version;
 use serde::Deserialize;
 
-use crate::{cfg_flag::CfgFlag, CargoConfig, CargoFeatures, CargoWorkspace, Package};
+use crate::{
+    cfg_flag::CfgFlag, CargoConfig, CargoFeatures, CargoWorkspace, InvocationLocation,
+    InvocationStrategy, Package,
+};
 
 #[derive(Debug, Default, Clone, PartialEq, Eq)]
 pub struct WorkspaceBuildScripts {
-    outputs: ArenaMap<Package, Option<BuildScriptOutput>>,
+    outputs: ArenaMap<Package, BuildScriptOutput>,
     error: Option<String>,
 }
 
@@ -38,76 +46,57 @@ pub(crate) struct BuildScriptOutput {
     pub(crate) proc_macro_dylib_path: Option<AbsPathBuf>,
 }
 
+impl BuildScriptOutput {
+    fn is_unchanged(&self) -> bool {
+        self.cfgs.is_empty()
+            && self.envs.is_empty()
+            && self.out_dir.is_none()
+            && self.proc_macro_dylib_path.is_none()
+    }
+}
+
 impl WorkspaceBuildScripts {
-    fn build_command(config: &CargoConfig) -> Command {
-        if let Some([program, args @ ..]) = config.run_build_script_command.as_deref() {
-            let mut cmd = Command::new(program);
-            cmd.args(args);
-            cmd.envs(&config.extra_env);
-            return cmd;
-        }
+    fn build_command(config: &CargoConfig) -> io::Result<Command> {
+        let mut cmd = match config.run_build_script_command.as_deref() {
+            Some([program, args @ ..]) => {
+                let mut cmd = Command::new(program);
+                cmd.args(args);
+                cmd
+            }
+            _ => {
+                let mut cmd = Command::new(toolchain::cargo());
+
+                cmd.args(&["check", "--quiet", "--workspace", "--message-format=json"]);
+
+                // --all-targets includes tests, benches and examples in addition to the
+                // default lib and bins. This is an independent concept from the --targets
+                // flag below.
+                cmd.arg("--all-targets");
+
+                if let Some(target) = &config.target {
+                    cmd.args(&["--target", target]);
+                }
+
+                match &config.features {
+                    CargoFeatures::All => {
+                        cmd.arg("--all-features");
+                    }
+                    CargoFeatures::Selected { features, no_default_features } => {
+                        if *no_default_features {
+                            cmd.arg("--no-default-features");
+                        }
+                        if !features.is_empty() {
+                            cmd.arg("--features");
+                            cmd.arg(features.join(" "));
+                        }
+                    }
+                }
+
+                cmd
+            }
+        };
 
-        let mut cmd = Command::new(toolchain::cargo());
         cmd.envs(&config.extra_env);
-        cmd.args(&["check", "--quiet", "--workspace", "--message-format=json"]);
-
-        // --all-targets includes tests, benches and examples in addition to the
-        // default lib and bins. This is an independent concept from the --targets
-        // flag below.
-        cmd.arg("--all-targets");
-
-        if let Some(target) = &config.target {
-            cmd.args(&["--target", target]);
-        }
-
-        match &config.features {
-            CargoFeatures::All => {
-                cmd.arg("--all-features");
-            }
-            CargoFeatures::Selected { features, no_default_features } => {
-                if *no_default_features {
-                    cmd.arg("--no-default-features");
-                }
-                if !features.is_empty() {
-                    cmd.arg("--features");
-                    cmd.arg(features.join(" "));
-                }
-            }
-        }
-
-        cmd
-    }
-
-    pub(crate) fn run(
-        config: &CargoConfig,
-        workspace: &CargoWorkspace,
-        progress: &dyn Fn(String),
-        toolchain: &Option<Version>,
-    ) -> io::Result<WorkspaceBuildScripts> {
-        const RUST_1_62: Version = Version::new(1, 62, 0);
-
-        match Self::run_(Self::build_command(config), config, workspace, progress) {
-            Ok(WorkspaceBuildScripts { error: Some(error), .. })
-                if toolchain.as_ref().map_or(false, |it| *it >= RUST_1_62) =>
-            {
-                // building build scripts failed, attempt to build with --keep-going so
-                // that we potentially get more build data
-                let mut cmd = Self::build_command(config);
-                cmd.args(&["-Z", "unstable-options", "--keep-going"]).env("RUSTC_BOOTSTRAP", "1");
-                let mut res = Self::run_(cmd, config, workspace, progress)?;
-                res.error = Some(error);
-                Ok(res)
-            }
-            res => res,
-        }
-    }
-
-    fn run_(
-        mut cmd: Command,
-        config: &CargoConfig,
-        workspace: &CargoWorkspace,
-        progress: &dyn Fn(String),
-    ) -> io::Result<WorkspaceBuildScripts> {
         if config.wrap_rustc_in_build_scripts {
             // Setup RUSTC_WRAPPER to point to `rust-analyzer` binary itself. We use
             // that to compile only proc macros and build scripts during the initial
@@ -117,8 +106,126 @@ impl WorkspaceBuildScripts {
             cmd.env("RA_RUSTC_WRAPPER", "1");
         }
 
-        cmd.current_dir(workspace.workspace_root());
+        Ok(cmd)
+    }
 
+    /// Runs the build scripts for the given workspace
+    pub(crate) fn run_for_workspace(
+        config: &CargoConfig,
+        workspace: &CargoWorkspace,
+        progress: &dyn Fn(String),
+        toolchain: &Option<Version>,
+    ) -> io::Result<WorkspaceBuildScripts> {
+        const RUST_1_62: Version = Version::new(1, 62, 0);
+
+        let current_dir = match &config.invocation_location {
+            InvocationLocation::Root(root) if config.run_build_script_command.is_some() => {
+                root.as_path()
+            }
+            _ => &workspace.workspace_root(),
+        }
+        .as_ref();
+
+        match Self::run_per_ws(Self::build_command(config)?, workspace, current_dir, progress) {
+            Ok(WorkspaceBuildScripts { error: Some(error), .. })
+                if toolchain.as_ref().map_or(false, |it| *it >= RUST_1_62) =>
+            {
+                // building build scripts failed, attempt to build with --keep-going so
+                // that we potentially get more build data
+                let mut cmd = Self::build_command(config)?;
+                cmd.args(&["-Z", "unstable-options", "--keep-going"]).env("RUSTC_BOOTSTRAP", "1");
+                let mut res = Self::run_per_ws(cmd, workspace, current_dir, progress)?;
+                res.error = Some(error);
+                Ok(res)
+            }
+            res => res,
+        }
+    }
+
+    /// Runs the build scripts by invoking the configured command *once*.
+    /// This populates the outputs for all passed in workspaces.
+    pub(crate) fn run_once(
+        config: &CargoConfig,
+        workspaces: &[&CargoWorkspace],
+        progress: &dyn Fn(String),
+    ) -> io::Result<Vec<WorkspaceBuildScripts>> {
+        assert_eq!(config.invocation_strategy, InvocationStrategy::Once);
+
+        let current_dir = match &config.invocation_location {
+            InvocationLocation::Root(root) => root,
+            InvocationLocation::Workspace => {
+                return Err(io::Error::new(
+                    io::ErrorKind::Other,
+                    "Cannot run build scripts from workspace with invocation strategy `once`",
+                ))
+            }
+        };
+        let cmd = Self::build_command(config)?;
+        // NB: Cargo.toml could have been modified between `cargo metadata` and
+        // `cargo check`. We shouldn't assume that package ids we see here are
+        // exactly those from `config`.
+        let mut by_id = FxHashMap::default();
+        // some workspaces might depend on the same crates, so we need to duplicate the outputs
+        // to those collisions
+        let mut collisions = Vec::new();
+        let mut res: Vec<_> = workspaces
+            .iter()
+            .enumerate()
+            .map(|(idx, workspace)| {
+                let mut res = WorkspaceBuildScripts::default();
+                for package in workspace.packages() {
+                    res.outputs.insert(package, BuildScriptOutput::default());
+                    if by_id.contains_key(&workspace[package].id) {
+                        collisions.push((&workspace[package].id, idx, package));
+                    } else {
+                        by_id.insert(workspace[package].id.clone(), (package, idx));
+                    }
+                }
+                res
+            })
+            .collect();
+
+        let errors = Self::run_command(
+            cmd,
+            current_dir.as_path().as_ref(),
+            |package, cb| {
+                if let Some(&(package, workspace)) = by_id.get(package) {
+                    cb(&workspaces[workspace][package].name, &mut res[workspace].outputs[package]);
+                }
+            },
+            progress,
+        )?;
+        res.iter_mut().for_each(|it| it.error = errors.clone());
+        collisions.into_iter().for_each(|(id, workspace, package)| {
+            if let Some(&(p, w)) = by_id.get(id) {
+                res[workspace].outputs[package] = res[w].outputs[p].clone();
+            }
+        });
+
+        if tracing::enabled!(tracing::Level::INFO) {
+            for (idx, workspace) in workspaces.iter().enumerate() {
+                for package in workspace.packages() {
+                    let package_build_data = &mut res[idx].outputs[package];
+                    if !package_build_data.is_unchanged() {
+                        tracing::info!(
+                            "{}: {:?}",
+                            workspace[package].manifest.parent().display(),
+                            package_build_data,
+                        );
+                    }
+                }
+            }
+        }
+
+        Ok(res)
+    }
+
+    fn run_per_ws(
+        cmd: Command,
+        workspace: &CargoWorkspace,
+        current_dir: &path::Path,
+        progress: &dyn Fn(String),
+    ) -> io::Result<WorkspaceBuildScripts> {
         let mut res = WorkspaceBuildScripts::default();
         let outputs = &mut res.outputs;
         // NB: Cargo.toml could have been modified between `cargo metadata` and
@@ -126,10 +233,46 @@ impl WorkspaceBuildScripts {
         // exactly those from `config`.
         let mut by_id: FxHashMap<String, Package> = FxHashMap::default();
         for package in workspace.packages() {
-            outputs.insert(package, None);
+            outputs.insert(package, BuildScriptOutput::default());
             by_id.insert(workspace[package].id.clone(), package);
         }
 
+        res.error = Self::run_command(
+            cmd,
+            current_dir,
+            |package, cb| {
+                if let Some(&package) = by_id.get(package) {
+                    cb(&workspace[package].name, &mut outputs[package]);
+                }
+            },
+            progress,
+        )?;
+
+        if tracing::enabled!(tracing::Level::INFO) {
+            for package in workspace.packages() {
+                let package_build_data = &mut outputs[package];
+                if !package_build_data.is_unchanged() {
+                    tracing::info!(
+                        "{}: {:?}",
+                        workspace[package].manifest.parent().display(),
+                        package_build_data,
+                    );
+                }
+            }
+        }
+
+        Ok(res)
+    }
+
+    fn run_command(
+        mut cmd: Command,
+        current_dir: &path::Path,
+        // ideally this would be something like:
+        // with_output_for: impl FnMut(&str, dyn FnOnce(&mut BuildScriptOutput)),
+        // but owned trait objects aren't a thing
+        mut with_output_for: impl FnMut(&str, &mut dyn FnMut(&str, &mut BuildScriptOutput)),
+        progress: &dyn Fn(String),
+    ) -> io::Result<Option<String>> {
         let errors = RefCell::new(String::new());
         let push_err = |err: &str| {
             let mut e = errors.borrow_mut();
@@ -137,7 +280,8 @@ impl WorkspaceBuildScripts {
             e.push('\n');
         };
 
-        tracing::info!("Running build scripts: {:?}", cmd);
+        tracing::info!("Running build scripts in {}: {:?}", current_dir.display(), cmd);
+        cmd.current_dir(current_dir);
         let output = stdx::process::spawn_with_streaming_output(
             cmd,
             &mut |line| {
@@ -149,61 +293,58 @@ impl WorkspaceBuildScripts {
                     .unwrap_or_else(|_| Message::TextLine(line.to_string()));
 
                 match message {
-                    Message::BuildScriptExecuted(message) => {
-                        let package = match by_id.get(&message.package_id.repr) {
-                            Some(&it) => it,
-                            None => return,
-                        };
-                        progress(format!("running build-script: {}", workspace[package].name));
-
-                        let cfgs = {
-                            let mut acc = Vec::new();
-                            for cfg in message.cfgs {
-                                match cfg.parse::<CfgFlag>() {
-                                    Ok(it) => acc.push(it),
-                                    Err(err) => {
-                                        push_err(&format!(
-                                            "invalid cfg from cargo-metadata: {}",
-                                            err
-                                        ));
-                                        return;
-                                    }
-                                };
+                    Message::BuildScriptExecuted(mut message) => {
+                        with_output_for(&message.package_id.repr, &mut |name, data| {
+                            progress(format!("running build-script: {}", name));
+                            let cfgs = {
+                                let mut acc = Vec::new();
+                                for cfg in &message.cfgs {
+                                    match cfg.parse::<CfgFlag>() {
+                                        Ok(it) => acc.push(it),
+                                        Err(err) => {
+                                            push_err(&format!(
+                                                "invalid cfg from cargo-metadata: {}",
+                                                err
+                                            ));
+                                            return;
+                                        }
+                                    };
+                                }
+                                acc
+                            };
+                            if !message.env.is_empty() {
+                                data.envs = mem::take(&mut message.env);
                             }
-                            acc
-                        };
-                        // cargo_metadata crate returns default (empty) path for
-                        // older cargos, which is not absolute, so work around that.
-                        let out_dir = message.out_dir.into_os_string();
-                        if !out_dir.is_empty() {
-                            let data = outputs[package].get_or_insert_with(Default::default);
-                            data.out_dir = Some(AbsPathBuf::assert(PathBuf::from(out_dir)));
-                            data.cfgs = cfgs;
-                        }
-                        if !message.env.is_empty() {
-                            outputs[package].get_or_insert_with(Default::default).envs =
-                                message.env;
-                        }
+                            // cargo_metadata crate returns default (empty) path for
+                            // older cargos, which is not absolute, so work around that.
+                            let out_dir = mem::take(&mut message.out_dir).into_os_string();
+                            if !out_dir.is_empty() {
+                                let out_dir = AbsPathBuf::assert(PathBuf::from(out_dir));
+                                // inject_cargo_env(package, package_build_data);
+                                // NOTE: cargo and rustc seem to hide non-UTF-8 strings from env! and option_env!()
+                                if let Some(out_dir) =
+                                    out_dir.as_os_str().to_str().map(|s| s.to_owned())
+                                {
+                                    data.envs.push(("OUT_DIR".to_string(), out_dir));
+                                }
+                                data.out_dir = Some(out_dir);
+                                data.cfgs = cfgs;
+                            }
+                        });
                     }
                     Message::CompilerArtifact(message) => {
-                        let package = match by_id.get(&message.package_id.repr) {
-                            Some(it) => *it,
-                            None => return,
-                        };
-
-                        progress(format!("building proc-macros: {}", message.target.name));
-
-                        if message.target.kind.iter().any(|k| k == "proc-macro") {
-                            // Skip rmeta file
-                            if let Some(filename) =
-                                message.filenames.iter().find(|name| is_dylib(name))
-                            {
-                                let filename = AbsPathBuf::assert(PathBuf::from(&filename));
-                                outputs[package]
-                                    .get_or_insert_with(Default::default)
-                                    .proc_macro_dylib_path = Some(filename);
+                        with_output_for(&message.package_id.repr, &mut |name, data| {
+                            progress(format!("building proc-macros: {}", name));
+                            if message.target.kind.iter().any(|k| k == "proc-macro") {
+                                // Skip rmeta file
+                                if let Some(filename) =
+                                    message.filenames.iter().find(|name| is_dylib(name))
+                                {
+                                    let filename = AbsPathBuf::assert(PathBuf::from(&filename));
+                                    data.proc_macro_dylib_path = Some(filename);
+                                }
                             }
-                        }
+                        });
                     }
                     Message::CompilerMessage(message) => {
                         progress(message.target.name);
@@ -222,32 +363,13 @@ impl WorkspaceBuildScripts {
             },
         )?;
 
-        for package in workspace.packages() {
-            if let Some(package_build_data) = &mut outputs[package] {
-                tracing::info!(
-                    "{}: {:?}",
-                    workspace[package].manifest.parent().display(),
-                    package_build_data,
-                );
-                // inject_cargo_env(package, package_build_data);
-                if let Some(out_dir) = &package_build_data.out_dir {
-                    // NOTE: cargo and rustc seem to hide non-UTF-8 strings from env! and option_env!()
-                    if let Some(out_dir) = out_dir.as_os_str().to_str().map(|s| s.to_owned()) {
-                        package_build_data.envs.push(("OUT_DIR".to_string(), out_dir));
-                    }
-                }
-            }
-        }
-
-        let mut errors = errors.into_inner();
-        if !output.status.success() {
-            if errors.is_empty() {
-                errors = "cargo check failed".to_string();
-            }
-            res.error = Some(errors);
-        }
-
-        Ok(res)
+        let errors = if !output.status.success() {
+            let errors = errors.into_inner();
+            Some(if errors.is_empty() { "cargo check failed".to_string() } else { errors })
+        } else {
+            None
+        };
+        Ok(errors)
     }
 
     pub fn error(&self) -> Option<&str> {
@@ -255,11 +377,11 @@ impl WorkspaceBuildScripts {
     }
 
     pub(crate) fn get_output(&self, idx: Package) -> Option<&BuildScriptOutput> {
-        self.outputs.get(idx)?.as_ref()
+        self.outputs.get(idx)
     }
 }
 
-// FIXME: File a better way to know if it is a dylib.
+// FIXME: Find a better way to know if it is a dylib.
 fn is_dylib(path: &Utf8Path) -> bool {
     match path.extension().map(|e| e.to_string().to_lowercase()) {
         None => false,
diff --git a/src/tools/rust-analyzer/crates/project-model/src/cargo_workspace.rs b/src/tools/rust-analyzer/crates/project-model/src/cargo_workspace.rs
index 8e690f1125a0..b4c2ba436772 100644
--- a/src/tools/rust-analyzer/crates/project-model/src/cargo_workspace.rs
+++ b/src/tools/rust-analyzer/crates/project-model/src/cargo_workspace.rs
@@ -14,8 +14,8 @@ use rustc_hash::FxHashMap;
 use serde::Deserialize;
 use serde_json::from_value;
 
-use crate::CfgOverrides;
-use crate::{utf8_stdout, ManifestPath};
+use crate::{utf8_stdout, InvocationLocation, ManifestPath};
+use crate::{CfgOverrides, InvocationStrategy};
 
 /// [`CargoWorkspace`] represents the logical structure of, well, a Cargo
 /// workspace. It pretty closely mirrors `cargo metadata` output.
@@ -106,6 +106,8 @@ pub struct CargoConfig {
     pub run_build_script_command: Option<Vec<String>>,
     /// Extra env vars to set when invoking the cargo command
     pub extra_env: FxHashMap<String, String>,
+    pub invocation_strategy: InvocationStrategy,
+    pub invocation_location: InvocationLocation,
 }
 
 impl CargoConfig {
@@ -283,8 +285,6 @@ impl CargoWorkspace {
             }
             CargoFeatures::Selected { features, no_default_features } => {
                 if *no_default_features {
-                    // FIXME: `NoDefaultFeatures` is mutual exclusive with `SomeFeatures`
-                    // https://github.com/oli-obk/cargo_metadata/issues/79
                     meta.features(CargoOpt::NoDefaultFeatures);
                 }
                 if !features.is_empty() {
@@ -329,18 +329,21 @@ impl CargoWorkspace {
         let ws_members = &meta.workspace_members;
 
         meta.packages.sort_by(|a, b| a.id.cmp(&b.id));
-        for meta_pkg in &meta.packages {
+        for meta_pkg in meta.packages {
             let cargo_metadata::Package {
-                id,
-                edition,
                 name,
-                manifest_path,
                 version,
-                metadata,
+                id,
+                source,
+                targets: meta_targets,
+                features,
+                manifest_path,
                 repository,
+                edition,
+                metadata,
                 ..
             } = meta_pkg;
-            let meta = from_value::<PackageMetadata>(metadata.clone()).unwrap_or_default();
+            let meta = from_value::<PackageMetadata>(metadata).unwrap_or_default();
             let edition = match edition {
                 cargo_metadata::Edition::E2015 => Edition::Edition2015,
                 cargo_metadata::Edition::E2018 => Edition::Edition2018,
@@ -352,35 +355,36 @@ impl CargoWorkspace {
             };
             // We treat packages without source as "local" packages. That includes all members of
             // the current workspace, as well as any path dependency outside the workspace.
-            let is_local = meta_pkg.source.is_none();
-            let is_member = ws_members.contains(id);
+            let is_local = source.is_none();
+            let is_member = ws_members.contains(&id);
 
             let pkg = packages.alloc(PackageData {
                 id: id.repr.clone(),
-                name: name.clone(),
-                version: version.clone(),
-                manifest: AbsPathBuf::assert(PathBuf::from(&manifest_path)).try_into().unwrap(),
+                name,
+                version,
+                manifest: AbsPathBuf::assert(manifest_path.into()).try_into().unwrap(),
                 targets: Vec::new(),
                 is_local,
                 is_member,
                 edition,
-                repository: repository.clone(),
+                repository,
                 dependencies: Vec::new(),
-                features: meta_pkg.features.clone().into_iter().collect(),
+                features: features.into_iter().collect(),
                 active_features: Vec::new(),
                 metadata: meta.rust_analyzer.unwrap_or_default(),
             });
             let pkg_data = &mut packages[pkg];
             pkg_by_id.insert(id, pkg);
-            for meta_tgt in &meta_pkg.targets {
-                let is_proc_macro = meta_tgt.kind.as_slice() == ["proc-macro"];
+            for meta_tgt in meta_targets {
+                let cargo_metadata::Target { name, kind, required_features, src_path, .. } =
+                    meta_tgt;
                 let tgt = targets.alloc(TargetData {
                     package: pkg,
-                    name: meta_tgt.name.clone(),
-                    root: AbsPathBuf::assert(PathBuf::from(&meta_tgt.src_path)),
-                    kind: TargetKind::new(meta_tgt.kind.as_slice()),
-                    is_proc_macro,
-                    required_features: meta_tgt.required_features.clone(),
+                    name,
+                    root: AbsPathBuf::assert(src_path.into()),
+                    kind: TargetKind::new(&kind),
+                    is_proc_macro: &*kind == ["proc-macro"],
+                    required_features,
                 });
                 pkg_data.targets.push(tgt);
             }
diff --git a/src/tools/rust-analyzer/crates/project-model/src/lib.rs b/src/tools/rust-analyzer/crates/project-model/src/lib.rs
index ce78ce85697a..575581fa543a 100644
--- a/src/tools/rust-analyzer/crates/project-model/src/lib.rs
+++ b/src/tools/rust-analyzer/crates/project-model/src/lib.rs
@@ -67,7 +67,7 @@ impl ProjectManifest {
         if path.file_name().unwrap_or_default() == "Cargo.toml" {
             return Ok(ProjectManifest::CargoToml(path));
         }
-        bail!("project root must point to Cargo.toml or rust-project.json: {}", path.display())
+        bail!("project root must point to Cargo.toml or rust-project.json: {}", path.display());
     }
 
     pub fn discover_single(path: &AbsPath) -> Result<ProjectManifest> {
@@ -78,7 +78,7 @@ impl ProjectManifest {
         };
 
         if !candidates.is_empty() {
-            bail!("more than one project")
+            bail!("more than one project");
         }
         Ok(res)
     }
@@ -157,3 +157,17 @@ fn utf8_stdout(mut cmd: Command) -> Result<String> {
     let stdout = String::from_utf8(output.stdout)?;
     Ok(stdout.trim().to_string())
 }
+
+#[derive(Copy, Clone, Debug, Default, PartialEq, Eq)]
+pub enum InvocationStrategy {
+    Once,
+    #[default]
+    PerWorkspace,
+}
+
+#[derive(Clone, Debug, Default, PartialEq, Eq)]
+pub enum InvocationLocation {
+    Root(AbsPathBuf),
+    #[default]
+    Workspace,
+}
diff --git a/src/tools/rust-analyzer/crates/project-model/src/sysroot.rs b/src/tools/rust-analyzer/crates/project-model/src/sysroot.rs
index bc37e3d132a6..fa8d76f3f452 100644
--- a/src/tools/rust-analyzer/crates/project-model/src/sysroot.rs
+++ b/src/tools/rust-analyzer/crates/project-model/src/sysroot.rs
@@ -64,14 +64,15 @@ impl Sysroot {
         self.by_name("proc_macro")
     }
 
-    pub fn crates<'a>(&'a self) -> impl Iterator<Item = SysrootCrate> + ExactSizeIterator + 'a {
+    pub fn crates(&self) -> impl Iterator<Item = SysrootCrate> + ExactSizeIterator + '_ {
         self.crates.iter().map(|(id, _data)| id)
     }
 }
 
 impl Sysroot {
+    /// Attempts to discover the toolchain's sysroot from the given `dir`.
     pub fn discover(dir: &AbsPath, extra_env: &FxHashMap<String, String>) -> Result<Sysroot> {
-        tracing::debug!("Discovering sysroot for {}", dir.display());
+        tracing::debug!("discovering sysroot for {}", dir.display());
         let sysroot_dir = discover_sysroot_dir(dir, extra_env)?;
         let sysroot_src_dir =
             discover_sysroot_src_dir_or_add_component(&sysroot_dir, dir, extra_env)?;
@@ -83,11 +84,10 @@ impl Sysroot {
         cargo_toml: &ManifestPath,
         extra_env: &FxHashMap<String, String>,
     ) -> Option<ManifestPath> {
-        tracing::debug!("Discovering rustc source for {}", cargo_toml.display());
+        tracing::debug!("discovering rustc source for {}", cargo_toml.display());
         let current_dir = cargo_toml.parent();
-        discover_sysroot_dir(current_dir, extra_env)
-            .ok()
-            .and_then(|sysroot_dir| get_rustc_src(&sysroot_dir))
+        let sysroot_dir = discover_sysroot_dir(current_dir, extra_env).ok()?;
+        get_rustc_src(&sysroot_dir)
     }
 
     pub fn with_sysroot_dir(sysroot_dir: AbsPathBuf) -> Result<Sysroot> {
@@ -189,6 +189,7 @@ fn discover_sysroot_src_dir(sysroot_path: &AbsPathBuf) -> Option<AbsPathBuf> {
 
     get_rust_src(sysroot_path)
 }
+
 fn discover_sysroot_src_dir_or_add_component(
     sysroot_path: &AbsPathBuf,
     current_dir: &AbsPath,
@@ -199,6 +200,7 @@ fn discover_sysroot_src_dir_or_add_component(
             let mut rustup = Command::new(toolchain::rustup());
             rustup.envs(extra_env);
             rustup.current_dir(current_dir).args(&["component", "add", "rust-src"]);
+            tracing::info!("adding rust-src component by {:?}", rustup);
             utf8_stdout(rustup).ok()?;
             get_rust_src(sysroot_path)
         })
@@ -217,7 +219,7 @@ try installing the Rust source the same way you installed rustc",
 fn get_rustc_src(sysroot_path: &AbsPath) -> Option<ManifestPath> {
     let rustc_src = sysroot_path.join("lib/rustlib/rustc-src/rust/compiler/rustc/Cargo.toml");
     let rustc_src = ManifestPath::try_from(rustc_src).ok()?;
-    tracing::debug!("Checking for rustc source code: {}", rustc_src.display());
+    tracing::debug!("checking for rustc source code: {}", rustc_src.display());
     if fs::metadata(&rustc_src).is_ok() {
         Some(rustc_src)
     } else {
@@ -227,7 +229,7 @@ fn get_rustc_src(sysroot_path: &AbsPath) -> Option<ManifestPath> {
 
 fn get_rust_src(sysroot_path: &AbsPath) -> Option<AbsPathBuf> {
     let rust_src = sysroot_path.join("lib/rustlib/src/rust/library");
-    tracing::debug!("Checking sysroot: {}", rust_src.display());
+    tracing::debug!("checking sysroot library: {}", rust_src.display());
     if fs::metadata(&rust_src).is_ok() {
         Some(rust_src)
     } else {
diff --git a/src/tools/rust-analyzer/crates/project-model/src/workspace.rs b/src/tools/rust-analyzer/crates/project-model/src/workspace.rs
index 72ddf809288a..2780c62ed118 100644
--- a/src/tools/rust-analyzer/crates/project-model/src/workspace.rs
+++ b/src/tools/rust-analyzer/crates/project-model/src/workspace.rs
@@ -2,7 +2,7 @@
 //! metadata` or `rust-project.json`) into representation stored in the salsa
 //! database -- `CrateGraph`.
 
-use std::{collections::VecDeque, fmt, fs, process::Command};
+use std::{collections::VecDeque, fmt, fs, process::Command, sync::Arc};
 
 use anyhow::{format_err, Context, Result};
 use base_db::{
@@ -21,8 +21,8 @@ use crate::{
     cfg_flag::CfgFlag,
     rustc_cfg,
     sysroot::SysrootCrate,
-    utf8_stdout, CargoConfig, CargoWorkspace, ManifestPath, Package, ProjectJson, ProjectManifest,
-    Sysroot, TargetKind, WorkspaceBuildScripts,
+    utf8_stdout, CargoConfig, CargoWorkspace, InvocationStrategy, ManifestPath, Package,
+    ProjectJson, ProjectManifest, Sysroot, TargetKind, WorkspaceBuildScripts,
 };
 
 /// A set of cfg-overrides per crate.
@@ -209,6 +209,9 @@ impl ProjectWorkspace {
                     ),
                     None => None,
                 };
+                if let Some(sysroot) = &sysroot {
+                    tracing::info!(src_root = %sysroot.src_root().display(), root = %sysroot.root().display(), "Using sysroot");
+                }
 
                 let rustc_dir = match &config.rustc_source {
                     Some(RustcSource::Path(path)) => ManifestPath::try_from(path.clone()).ok(),
@@ -217,6 +220,9 @@ impl ProjectWorkspace {
                     }
                     None => None,
                 };
+                if let Some(rustc_dir) = &rustc_dir {
+                    tracing::info!(rustc_dir = %rustc_dir.display(), "Using rustc source");
+                }
 
                 let rustc = match rustc_dir {
                     Some(rustc_dir) => Some({
@@ -277,6 +283,9 @@ impl ProjectWorkspace {
             }
             (None, None) => None,
         };
+        if let Some(sysroot) = &sysroot {
+            tracing::info!(src_root = %sysroot.src_root().display(), root = %sysroot.root().display(), "Using sysroot");
+        }
 
         let rustc_cfg = rustc_cfg::get(None, target, extra_env);
         Ok(ProjectWorkspace::Json { project: project_json, sysroot, rustc_cfg })
@@ -294,6 +303,7 @@ impl ProjectWorkspace {
         Ok(ProjectWorkspace::DetachedFiles { files: detached_files, sysroot, rustc_cfg })
     }
 
+    /// Runs the build scripts for this [`ProjectWorkspace`].
     pub fn run_build_scripts(
         &self,
         config: &CargoConfig,
@@ -301,9 +311,13 @@ impl ProjectWorkspace {
     ) -> Result<WorkspaceBuildScripts> {
         match self {
             ProjectWorkspace::Cargo { cargo, toolchain, .. } => {
-                WorkspaceBuildScripts::run(config, cargo, progress, toolchain).with_context(|| {
-                    format!("Failed to run build scripts for {}", &cargo.workspace_root().display())
-                })
+                WorkspaceBuildScripts::run_for_workspace(config, cargo, progress, toolchain)
+                    .with_context(|| {
+                        format!(
+                            "Failed to run build scripts for {}",
+                            &cargo.workspace_root().display()
+                        )
+                    })
             }
             ProjectWorkspace::Json { .. } | ProjectWorkspace::DetachedFiles { .. } => {
                 Ok(WorkspaceBuildScripts::default())
@@ -311,6 +325,49 @@ impl ProjectWorkspace {
         }
     }
 
+    /// Runs the build scripts for the given [`ProjectWorkspace`]s. Depending on the invocation
+    /// strategy this may run a single build process for all project workspaces.
+    pub fn run_all_build_scripts(
+        workspaces: &[ProjectWorkspace],
+        config: &CargoConfig,
+        progress: &dyn Fn(String),
+    ) -> Vec<Result<WorkspaceBuildScripts>> {
+        if matches!(config.invocation_strategy, InvocationStrategy::PerWorkspace)
+            || config.run_build_script_command.is_none()
+        {
+            return workspaces.iter().map(|it| it.run_build_scripts(config, progress)).collect();
+        }
+
+        let cargo_ws: Vec<_> = workspaces
+            .iter()
+            .filter_map(|it| match it {
+                ProjectWorkspace::Cargo { cargo, .. } => Some(cargo),
+                _ => None,
+            })
+            .collect();
+        let ref mut outputs = match WorkspaceBuildScripts::run_once(config, &cargo_ws, progress) {
+            Ok(it) => Ok(it.into_iter()),
+            // io::Error is not Clone?
+            Err(e) => Err(Arc::new(e)),
+        };
+
+        workspaces
+            .iter()
+            .map(|it| match it {
+                ProjectWorkspace::Cargo { cargo, .. } => match outputs {
+                    Ok(outputs) => Ok(outputs.next().unwrap()),
+                    Err(e) => Err(e.clone()).with_context(|| {
+                        format!(
+                            "Failed to run build scripts for {}",
+                            &cargo.workspace_root().display()
+                        )
+                    }),
+                },
+                _ => Ok(WorkspaceBuildScripts::default()),
+            })
+            .collect()
+    }
+
     pub fn set_build_scripts(&mut self, bs: WorkspaceBuildScripts) {
         match self {
             ProjectWorkspace::Cargo { build_scripts, .. } => *build_scripts = bs,
diff --git a/src/tools/rust-analyzer/crates/rust-analyzer/Cargo.toml b/src/tools/rust-analyzer/crates/rust-analyzer/Cargo.toml
index 5445028536cb..7ae5324ab051 100644
--- a/src/tools/rust-analyzer/crates/rust-analyzer/Cargo.toml
+++ b/src/tools/rust-analyzer/crates/rust-analyzer/Cargo.toml
@@ -23,7 +23,7 @@ crossbeam-channel = "0.5.5"
 dissimilar = "1.0.4"
 itertools = "0.10.5"
 scip = "0.1.1"
-lsp-types = { version = "0.93.1", features = ["proposed"] }
+lsp-types = { version = "=0.93.2", features = ["proposed"] }
 parking_lot = "0.12.1"
 xflags = "0.3.0"
 oorandom = "11.1.3"
diff --git a/src/tools/rust-analyzer/crates/rust-analyzer/src/bin/main.rs b/src/tools/rust-analyzer/crates/rust-analyzer/src/bin/main.rs
index eabfcf1944df..7bf595d2a45f 100644
--- a/src/tools/rust-analyzer/crates/rust-analyzer/src/bin/main.rs
+++ b/src/tools/rust-analyzer/crates/rust-analyzer/src/bin/main.rs
@@ -11,7 +11,7 @@ use std::{env, fs, path::Path, process};
 
 use lsp_server::Connection;
 use project_model::ProjectManifest;
-use rust_analyzer::{cli::flags, config::Config, from_json, lsp_ext::supports_utf8, Result};
+use rust_analyzer::{cli::flags, config::Config, from_json, Result};
 use vfs::AbsPathBuf;
 
 #[cfg(all(feature = "mimalloc"))]
@@ -191,11 +191,7 @@ fn run_server() -> Result<()> {
             name: String::from("rust-analyzer"),
             version: Some(rust_analyzer::version().to_string()),
         }),
-        offset_encoding: if supports_utf8(config.caps()) {
-            Some("utf-8".to_string())
-        } else {
-            None
-        },
+        offset_encoding: None,
     };
 
     let initialize_result = serde_json::to_value(initialize_result).unwrap();
diff --git a/src/tools/rust-analyzer/crates/rust-analyzer/src/caps.rs b/src/tools/rust-analyzer/crates/rust-analyzer/src/caps.rs
index cda95cd8626c..723b888d9abc 100644
--- a/src/tools/rust-analyzer/crates/rust-analyzer/src/caps.rs
+++ b/src/tools/rust-analyzer/crates/rust-analyzer/src/caps.rs
@@ -6,19 +6,25 @@ use lsp_types::{
     FileOperationFilter, FileOperationPattern, FileOperationPatternKind,
     FileOperationRegistrationOptions, FoldingRangeProviderCapability, HoverProviderCapability,
     ImplementationProviderCapability, InlayHintOptions, InlayHintServerCapabilities, OneOf,
-    RenameOptions, SaveOptions, SelectionRangeProviderCapability, SemanticTokensFullOptions,
-    SemanticTokensLegend, SemanticTokensOptions, ServerCapabilities, SignatureHelpOptions,
-    TextDocumentSyncCapability, TextDocumentSyncKind, TextDocumentSyncOptions,
-    TypeDefinitionProviderCapability, WorkDoneProgressOptions,
+    PositionEncodingKind, RenameOptions, SaveOptions, SelectionRangeProviderCapability,
+    SemanticTokensFullOptions, SemanticTokensLegend, SemanticTokensOptions, ServerCapabilities,
+    SignatureHelpOptions, TextDocumentSyncCapability, TextDocumentSyncKind,
+    TextDocumentSyncOptions, TypeDefinitionProviderCapability, WorkDoneProgressOptions,
     WorkspaceFileOperationsServerCapabilities, WorkspaceServerCapabilities,
 };
 use serde_json::json;
 
 use crate::config::{Config, RustfmtConfig};
+use crate::lsp_ext::supports_utf8;
 use crate::semantic_tokens;
 
 pub fn server_capabilities(config: &Config) -> ServerCapabilities {
     ServerCapabilities {
+        position_encoding: if supports_utf8(config.caps()) {
+            Some(PositionEncodingKind::UTF8)
+        } else {
+            None
+        },
         text_document_sync: Some(TextDocumentSyncCapability::Options(TextDocumentSyncOptions {
             open_close: Some(true),
             change: Some(TextDocumentSyncKind::INCREMENTAL),
diff --git a/src/tools/rust-analyzer/crates/rust-analyzer/src/cargo_target_spec.rs b/src/tools/rust-analyzer/crates/rust-analyzer/src/cargo_target_spec.rs
index e1675a030c0f..6ede194babc2 100644
--- a/src/tools/rust-analyzer/crates/rust-analyzer/src/cargo_target_spec.rs
+++ b/src/tools/rust-analyzer/crates/rust-analyzer/src/cargo_target_spec.rs
@@ -118,7 +118,7 @@ impl CargoTargetSpec {
         global_state_snapshot: &GlobalStateSnapshot,
         file_id: FileId,
     ) -> Result<Option<CargoTargetSpec>> {
-        let crate_id = match &*global_state_snapshot.analysis.crate_for(file_id)? {
+        let crate_id = match &*global_state_snapshot.analysis.crates_for(file_id)? {
             &[crate_id, ..] => crate_id,
             _ => return Ok(None),
         };
diff --git a/src/tools/rust-analyzer/crates/rust-analyzer/src/cli/lsif.rs b/src/tools/rust-analyzer/crates/rust-analyzer/src/cli/lsif.rs
index 748306ea57d4..c74ddabb1777 100644
--- a/src/tools/rust-analyzer/crates/rust-analyzer/src/cli/lsif.rs
+++ b/src/tools/rust-analyzer/crates/rust-analyzer/src/cli/lsif.rs
@@ -20,7 +20,7 @@ use crate::cli::{
     load_cargo::{load_workspace, LoadCargoConfig},
     Result,
 };
-use crate::line_index::{LineEndings, LineIndex, OffsetEncoding};
+use crate::line_index::{LineEndings, LineIndex, PositionEncoding};
 use crate::to_proto;
 use crate::version::version;
 
@@ -106,12 +106,12 @@ impl LsifManager<'_> {
                 manager: "cargo".to_string(),
                 uri: None,
                 content: None,
-                repository: Some(lsif::Repository {
-                    url: pi.repo,
+                repository: pi.repo.map(|url| lsif::Repository {
+                    url,
                     r#type: "git".to_string(),
                     commit_id: None,
                 }),
-                version: Some(pi.version),
+                version: pi.version,
             }));
         self.package_map.insert(package_information, result_set_id);
         result_set_id
@@ -126,7 +126,7 @@ impl LsifManager<'_> {
         let line_index = self.db.line_index(file_id);
         let line_index = LineIndex {
             index: line_index,
-            encoding: OffsetEncoding::Utf16,
+            encoding: PositionEncoding::Utf16,
             endings: LineEndings::Unix,
         };
         let range_id = self.add_vertex(lsif::Vertex::Range {
@@ -248,7 +248,7 @@ impl LsifManager<'_> {
         let line_index = self.db.line_index(file_id);
         let line_index = LineIndex {
             index: line_index,
-            encoding: OffsetEncoding::Utf16,
+            encoding: PositionEncoding::Utf16,
             endings: LineEndings::Unix,
         };
         let result = folds
diff --git a/src/tools/rust-analyzer/crates/rust-analyzer/src/cli/scip.rs b/src/tools/rust-analyzer/crates/rust-analyzer/src/cli/scip.rs
index 2c29b3ee3a6f..ca7ba896b67c 100644
--- a/src/tools/rust-analyzer/crates/rust-analyzer/src/cli/scip.rs
+++ b/src/tools/rust-analyzer/crates/rust-analyzer/src/cli/scip.rs
@@ -5,11 +5,11 @@ use std::{
     time::Instant,
 };
 
-use crate::line_index::{LineEndings, LineIndex, OffsetEncoding};
+use crate::line_index::{LineEndings, LineIndex, PositionEncoding};
 use hir::Name;
 use ide::{
-    LineCol, MonikerDescriptorKind, MonikerResult, StaticIndex, StaticIndexedFile, TextRange,
-    TokenId,
+    LineCol, MonikerDescriptorKind, StaticIndex, StaticIndexedFile, TextRange, TokenId,
+    TokenStaticData,
 };
 use ide_db::LineIndexDatabase;
 use project_model::{CargoConfig, ProjectManifest, ProjectWorkspace};
@@ -75,7 +75,7 @@ impl flags::Scip {
         let mut symbols_emitted: HashSet<TokenId> = HashSet::default();
         let mut tokens_to_symbol: HashMap<TokenId, String> = HashMap::new();
 
-        for file in si.files {
+        for StaticIndexedFile { file_id, tokens, .. } in si.files {
             let mut local_count = 0;
             let mut new_local_symbol = || {
                 let new_symbol = scip::types::Symbol::new_local(local_count);
@@ -84,7 +84,6 @@ impl flags::Scip {
                 new_symbol
             };
 
-            let StaticIndexedFile { file_id, tokens, .. } = file;
             let relative_path = match get_relative_filepath(&vfs, &rootpath, file_id) {
                 Some(relative_path) => relative_path,
                 None => continue,
@@ -92,7 +91,7 @@ impl flags::Scip {
 
             let line_index = LineIndex {
                 index: db.line_index(file_id),
-                encoding: OffsetEncoding::Utf8,
+                encoding: PositionEncoding::Utf8,
                 endings: LineEndings::Unix,
             };
 
@@ -107,28 +106,20 @@ impl flags::Scip {
 
                 let mut occurrence = scip_types::Occurrence::default();
                 occurrence.range = text_range_to_scip_range(&line_index, range);
-                occurrence.symbol = match tokens_to_symbol.get(&id) {
-                    Some(symbol) => symbol.clone(),
-                    None => {
-                        let symbol = match &token.moniker {
-                            Some(moniker) => moniker_to_symbol(&moniker),
-                            None => new_local_symbol(),
-                        };
-
-                        let symbol = scip::symbol::format_symbol(symbol);
-                        tokens_to_symbol.insert(id, symbol.clone());
-                        symbol
-                    }
-                };
+                occurrence.symbol = tokens_to_symbol
+                    .entry(id)
+                    .or_insert_with(|| {
+                        let symbol = token_to_symbol(&token).unwrap_or_else(&mut new_local_symbol);
+                        scip::symbol::format_symbol(symbol)
+                    })
+                    .clone();
 
                 if let Some(def) = token.definition {
                     if def.range == range {
                         occurrence.symbol_roles |= scip_types::SymbolRole::Definition as i32;
                     }
 
-                    if !symbols_emitted.contains(&id) {
-                        symbols_emitted.insert(id);
-
+                    if symbols_emitted.insert(id) {
                         let mut symbol_info = scip_types::SymbolInformation::default();
                         symbol_info.symbol = occurrence.symbol.clone();
                         if let Some(hover) = &token.hover {
@@ -207,9 +198,11 @@ fn new_descriptor(name: Name, suffix: scip_types::descriptor::Suffix) -> scip_ty
 ///
 /// Only returns a Symbol when it's a non-local symbol.
 ///     So if the visibility isn't outside of a document, then it will return None
-fn moniker_to_symbol(moniker: &MonikerResult) -> scip_types::Symbol {
+fn token_to_symbol(token: &TokenStaticData) -> Option<scip_types::Symbol> {
     use scip_types::descriptor::Suffix::*;
 
+    let moniker = token.moniker.as_ref()?;
+
     let package_name = moniker.package_information.name.clone();
     let version = moniker.package_information.version.clone();
     let descriptors = moniker
@@ -233,30 +226,26 @@ fn moniker_to_symbol(moniker: &MonikerResult) -> scip_types::Symbol {
         })
         .collect();
 
-    scip_types::Symbol {
+    Some(scip_types::Symbol {
         scheme: "rust-analyzer".into(),
         package: Some(scip_types::Package {
             manager: "cargo".to_string(),
             name: package_name,
-            version,
+            version: version.unwrap_or_else(|| ".".to_string()),
             ..Default::default()
         })
         .into(),
         descriptors,
         ..Default::default()
-    }
+    })
 }
 
 #[cfg(test)]
 mod test {
     use super::*;
-    use hir::Semantics;
-    use ide::{AnalysisHost, FilePosition};
-    use ide_db::defs::IdentClass;
-    use ide_db::{base_db::fixture::ChangeFixture, helpers::pick_best_token};
+    use ide::{AnalysisHost, FilePosition, StaticIndex, TextSize};
+    use ide_db::base_db::fixture::ChangeFixture;
     use scip::symbol::format_symbol;
-    use syntax::SyntaxKind::*;
-    use syntax::{AstNode, T};
 
     fn position(ra_fixture: &str) -> (AnalysisHost, FilePosition) {
         let mut host = AnalysisHost::default();
@@ -273,53 +262,33 @@ mod test {
     fn check_symbol(ra_fixture: &str, expected: &str) {
         let (host, position) = position(ra_fixture);
 
+        let analysis = host.analysis();
+        let si = StaticIndex::compute(&analysis);
+
         let FilePosition { file_id, offset } = position;
 
-        let db = host.raw_database();
-        let sema = &Semantics::new(db);
-        let file = sema.parse(file_id).syntax().clone();
-        let original_token = pick_best_token(file.token_at_offset(offset), |kind| match kind {
-            IDENT
-            | INT_NUMBER
-            | LIFETIME_IDENT
-            | T![self]
-            | T![super]
-            | T![crate]
-            | T![Self]
-            | COMMENT => 2,
-            kind if kind.is_trivia() => 0,
-            _ => 1,
-        })
-        .expect("OK OK");
-
-        let navs = sema
-            .descend_into_macros(original_token.clone())
-            .into_iter()
-            .filter_map(|token| {
-                IdentClass::classify_token(sema, &token).map(IdentClass::definitions).map(|it| {
-                    it.into_iter().flat_map(|def| {
-                        let module = def.module(db).unwrap();
-                        let current_crate = module.krate();
-
-                        match MonikerResult::from_def(sema.db, def, current_crate) {
-                            Some(moniker_result) => Some(moniker_to_symbol(&moniker_result)),
-                            None => None,
-                        }
-                    })
-                })
-            })
-            .flatten()
-            .collect::<Vec<_>>();
+        let mut found_symbol = None;
+        for file in &si.files {
+            if file.file_id != file_id {
+                continue;
+            }
+            for &(range, id) in &file.tokens {
+                if range.contains(offset - TextSize::from(1)) {
+                    let token = si.tokens.get(id).unwrap();
+                    found_symbol = token_to_symbol(token);
+                    break;
+                }
+            }
+        }
 
         if expected == "" {
-            assert_eq!(0, navs.len(), "must have no symbols {:?}", navs);
+            assert!(found_symbol.is_none(), "must have no symbols {:?}", found_symbol);
             return;
         }
 
-        assert_eq!(1, navs.len(), "must have one symbol {:?}", navs);
-
-        let res = navs.get(0).unwrap();
-        let formatted = format_symbol(res.clone());
+        assert!(found_symbol.is_some(), "must have one symbol {:?}", found_symbol);
+        let res = found_symbol.unwrap();
+        let formatted = format_symbol(res);
         assert_eq!(formatted, expected);
     }
 
@@ -446,4 +415,42 @@ pub mod module {
             "",
         );
     }
+
+    #[test]
+    fn global_symbol_for_pub_struct() {
+        check_symbol(
+            r#"
+    //- /lib.rs crate:main
+    mod foo;
+
+    fn main() {
+        let _bar = foo::Bar { i: 0 };
+    }
+    //- /foo.rs
+    pub struct Bar$0 {
+        pub i: i32,
+    }
+    "#,
+            "rust-analyzer cargo main . foo/Bar#",
+        );
+    }
+
+    #[test]
+    fn global_symbol_for_pub_struct_reference() {
+        check_symbol(
+            r#"
+    //- /lib.rs crate:main
+    mod foo;
+
+    fn main() {
+        let _bar = foo::Bar$0 { i: 0 };
+    }
+    //- /foo.rs
+    pub struct Bar {
+        pub i: i32,
+    }
+    "#,
+            "rust-analyzer cargo main . foo/Bar#",
+        );
+    }
 }
diff --git a/src/tools/rust-analyzer/crates/rust-analyzer/src/config.rs b/src/tools/rust-analyzer/crates/rust-analyzer/src/config.rs
index 577a8640a4c0..4072ae585dbd 100644
--- a/src/tools/rust-analyzer/crates/rust-analyzer/src/config.rs
+++ b/src/tools/rust-analyzer/crates/rust-analyzer/src/config.rs
@@ -32,7 +32,7 @@ use vfs::AbsPathBuf;
 use crate::{
     caps::completion_item_edit_resolve,
     diagnostics::DiagnosticsMapConfig,
-    line_index::OffsetEncoding,
+    line_index::PositionEncoding,
     lsp_ext::{self, supports_utf8, WorkspaceSymbolSearchKind, WorkspaceSymbolSearchScope},
 };
 
@@ -56,6 +56,9 @@ mod patch_old_style;
 // parsing the old name.
 config_data! {
     struct ConfigData {
+        /// Whether to insert #[must_use] when generating `as_` methods
+        /// for enum variants.
+        assist_emitMustUse: bool               = "false",
         /// Placeholder expression to use for missing expressions in assists.
         assist_expressionFillDefault: ExprFillDefaultDef              = "\"todo\"",
 
@@ -69,6 +72,19 @@ config_data! {
         cargo_autoreload: bool           = "true",
         /// Run build scripts (`build.rs`) for more precise code analysis.
         cargo_buildScripts_enable: bool  = "true",
+        /// Specifies the working directory for running build scripts.
+        /// - "workspace": run build scripts for a workspace in the workspace's root directory.
+        ///   This is incompatible with `#rust-analyzer.cargo.buildScripts.invocationStrategy#` set to `once`.
+        /// - "root": run build scripts in the project's root directory.
+        /// This config only has an effect when `#rust-analyzer.cargo.buildScripts.overrideCommand#`
+        /// is set.
+        cargo_buildScripts_invocationLocation: InvocationLocation = "\"workspace\"",
+        /// Specifies the invocation strategy to use when running the build scripts command.
+        /// If `per_workspace` is set, the command will be executed for each workspace.
+        /// If `once` is set, the command will be executed once.
+        /// This config only has an effect when `#rust-analyzer.cargo.buildScripts.overrideCommand#`
+        /// is set.
+        cargo_buildScripts_invocationStrategy: InvocationStrategy = "\"per_workspace\"",
         /// Override the command rust-analyzer uses to run build scripts and
         /// build procedural macros. The command is required to output json
         /// and should therefore include `--message-format=json` or a similar
@@ -122,6 +138,20 @@ config_data! {
         ///
         /// Set to `"all"` to pass `--all-features` to Cargo.
         checkOnSave_features: Option<CargoFeaturesDef>      = "null",
+        /// Specifies the working directory for running checks.
+        /// - "workspace": run checks for workspaces in the corresponding workspaces' root directories.
+        // FIXME: Ideally we would support this in some way
+        ///   This falls back to "root" if `#rust-analyzer.cargo.checkOnSave.invocationStrategy#` is set to `once`.
+        /// - "root": run checks in the project's root directory.
+        /// This config only has an effect when `#rust-analyzer.cargo.buildScripts.overrideCommand#`
+        /// is set.
+        checkOnSave_invocationLocation: InvocationLocation = "\"workspace\"",
+        /// Specifies the invocation strategy to use when running the checkOnSave command.
+        /// If `per_workspace` is set, the command will be executed for each workspace.
+        /// If `once` is set, the command will be executed once.
+        /// This config only has an effect when `#rust-analyzer.cargo.buildScripts.overrideCommand#`
+        /// is set.
+        checkOnSave_invocationStrategy: InvocationStrategy = "\"per_workspace\"",
         /// Whether to pass `--no-default-features` to Cargo. Defaults to
         /// `#rust-analyzer.cargo.noDefaultFeatures#`.
         checkOnSave_noDefaultFeatures: Option<bool>      = "null",
@@ -921,11 +951,11 @@ impl Config {
         .is_some()
     }
 
-    pub fn offset_encoding(&self) -> OffsetEncoding {
+    pub fn position_encoding(&self) -> PositionEncoding {
         if supports_utf8(&self.caps) {
-            OffsetEncoding::Utf8
+            PositionEncoding::Utf8
         } else {
-            OffsetEncoding::Utf16
+            PositionEncoding::Utf16
         }
     }
 
@@ -1056,6 +1086,16 @@ impl Config {
             rustc_source,
             unset_test_crates: UnsetTestCrates::Only(self.data.cargo_unsetTest.clone()),
             wrap_rustc_in_build_scripts: self.data.cargo_buildScripts_useRustcWrapper,
+            invocation_strategy: match self.data.cargo_buildScripts_invocationStrategy {
+                InvocationStrategy::Once => project_model::InvocationStrategy::Once,
+                InvocationStrategy::PerWorkspace => project_model::InvocationStrategy::PerWorkspace,
+            },
+            invocation_location: match self.data.cargo_buildScripts_invocationLocation {
+                InvocationLocation::Root => {
+                    project_model::InvocationLocation::Root(self.root_path.clone())
+                }
+                InvocationLocation::Workspace => project_model::InvocationLocation::Workspace,
+            },
             run_build_script_command: self.data.cargo_buildScripts_overrideCommand.clone(),
             extra_env: self.data.cargo_extraEnv.clone(),
         }
@@ -1087,6 +1127,18 @@ impl Config {
                     command,
                     args,
                     extra_env: self.check_on_save_extra_env(),
+                    invocation_strategy: match self.data.checkOnSave_invocationStrategy {
+                        InvocationStrategy::Once => flycheck::InvocationStrategy::Once,
+                        InvocationStrategy::PerWorkspace => {
+                            flycheck::InvocationStrategy::PerWorkspace
+                        }
+                    },
+                    invocation_location: match self.data.checkOnSave_invocationLocation {
+                        InvocationLocation::Root => {
+                            flycheck::InvocationLocation::Root(self.root_path.clone())
+                        }
+                        InvocationLocation::Workspace => flycheck::InvocationLocation::Workspace,
+                    },
                 }
             }
             Some(_) | None => FlycheckConfig::CargoCommand {
@@ -1227,6 +1279,7 @@ impl Config {
             allowed: None,
             insert_use: self.insert_use_config(),
             prefer_no_std: self.data.imports_prefer_no_std,
+            assist_emit_must_use: self.data.assist_emitMustUse,
         }
     }
 
@@ -1587,6 +1640,20 @@ enum CargoFeaturesDef {
     Selected(Vec<String>),
 }
 
+#[derive(Deserialize, Debug, Clone)]
+#[serde(rename_all = "snake_case")]
+enum InvocationStrategy {
+    Once,
+    PerWorkspace,
+}
+
+#[derive(Deserialize, Debug, Clone)]
+#[serde(rename_all = "snake_case")]
+enum InvocationLocation {
+    Root,
+    Workspace,
+}
+
 #[derive(Deserialize, Debug, Clone)]
 #[serde(untagged)]
 enum LifetimeElisionDef {
@@ -2001,6 +2068,22 @@ fn field_props(field: &str, ty: &str, doc: &[&str], default: &str) -> serde_json
                 "Render annotations above the whole item, including documentation comments and attributes."
             ],
         },
+        "InvocationStrategy" => set! {
+            "type": "string",
+            "enum": ["per_workspace", "once"],
+            "enumDescriptions": [
+                "The command will be executed for each workspace.",
+                "The command will be executed once."
+            ],
+        },
+        "InvocationLocation" => set! {
+            "type": "string",
+            "enum": ["workspace", "root"],
+            "enumDescriptions": [
+                "The command will be executed in the corresponding workspace root.",
+                "The command will be executed in the project root."
+            ],
+        },
         _ => panic!("missing entry for {}: {}", ty, default),
     }
 
diff --git a/src/tools/rust-analyzer/crates/rust-analyzer/src/diagnostics/to_proto.rs b/src/tools/rust-analyzer/crates/rust-analyzer/src/diagnostics/to_proto.rs
index 74689fd8757f..189ac2fbf533 100644
--- a/src/tools/rust-analyzer/crates/rust-analyzer/src/diagnostics/to_proto.rs
+++ b/src/tools/rust-analyzer/crates/rust-analyzer/src/diagnostics/to_proto.rs
@@ -8,7 +8,7 @@ use stdx::format_to;
 use vfs::{AbsPath, AbsPathBuf};
 
 use crate::{
-    global_state::GlobalStateSnapshot, line_index::OffsetEncoding, lsp_ext,
+    global_state::GlobalStateSnapshot, line_index::PositionEncoding, lsp_ext,
     to_proto::url_from_abs_path,
 };
 
@@ -66,17 +66,17 @@ fn location(
     let uri = url_from_abs_path(&file_name);
 
     let range = {
-        let offset_encoding = snap.config.offset_encoding();
+        let position_encoding = snap.config.position_encoding();
         lsp_types::Range::new(
-            position(&offset_encoding, span, span.line_start, span.column_start),
-            position(&offset_encoding, span, span.line_end, span.column_end),
+            position(&position_encoding, span, span.line_start, span.column_start),
+            position(&position_encoding, span, span.line_end, span.column_end),
         )
     };
     lsp_types::Location::new(uri, range)
 }
 
 fn position(
-    offset_encoding: &OffsetEncoding,
+    position_encoding: &PositionEncoding,
     span: &DiagnosticSpan,
     line_offset: usize,
     column_offset: usize,
@@ -93,9 +93,9 @@ fn position(
             };
         }
         let mut char_offset = 0;
-        let len_func = match offset_encoding {
-            OffsetEncoding::Utf8 => char::len_utf8,
-            OffsetEncoding::Utf16 => char::len_utf16,
+        let len_func = match position_encoding {
+            PositionEncoding::Utf8 => char::len_utf8,
+            PositionEncoding::Utf16 => char::len_utf16,
         };
         for c in line.text.chars() {
             char_offset += 1;
diff --git a/src/tools/rust-analyzer/crates/rust-analyzer/src/dispatch.rs b/src/tools/rust-analyzer/crates/rust-analyzer/src/dispatch.rs
index f16559148e65..57899b599146 100644
--- a/src/tools/rust-analyzer/crates/rust-analyzer/src/dispatch.rs
+++ b/src/tools/rust-analyzer/crates/rust-analyzer/src/dispatch.rs
@@ -52,7 +52,7 @@ impl<'a> RequestDispatcher<'a> {
             let _pctx = stdx::panic_context::enter(panic_context);
             f(self.global_state, params)
         };
-        if let Ok(response) = result_to_response::<R>(req.id.clone(), result) {
+        if let Ok(response) = result_to_response::<R>(req.id, result) {
             self.global_state.respond(response);
         }
 
@@ -80,7 +80,7 @@ impl<'a> RequestDispatcher<'a> {
             f(global_state_snapshot, params)
         });
 
-        if let Ok(response) = thread_result_to_response::<R>(req.id.clone(), result) {
+        if let Ok(response) = thread_result_to_response::<R>(req.id, result) {
             self.global_state.respond(response);
         }
 
diff --git a/src/tools/rust-analyzer/crates/rust-analyzer/src/from_proto.rs b/src/tools/rust-analyzer/crates/rust-analyzer/src/from_proto.rs
index f2db9a273349..936957bab488 100644
--- a/src/tools/rust-analyzer/crates/rust-analyzer/src/from_proto.rs
+++ b/src/tools/rust-analyzer/crates/rust-analyzer/src/from_proto.rs
@@ -8,7 +8,7 @@ use vfs::AbsPathBuf;
 use crate::{
     from_json,
     global_state::GlobalStateSnapshot,
-    line_index::{LineIndex, OffsetEncoding},
+    line_index::{LineIndex, PositionEncoding},
     lsp_ext,
     lsp_utils::invalid_params_error,
     Result,
@@ -25,10 +25,10 @@ pub(crate) fn vfs_path(url: &lsp_types::Url) -> Result<vfs::VfsPath> {
 
 pub(crate) fn offset(line_index: &LineIndex, position: lsp_types::Position) -> Result<TextSize> {
     let line_col = match line_index.encoding {
-        OffsetEncoding::Utf8 => {
+        PositionEncoding::Utf8 => {
             LineCol { line: position.line as u32, col: position.character as u32 }
         }
-        OffsetEncoding::Utf16 => {
+        PositionEncoding::Utf16 => {
             let line_col =
                 LineColUtf16 { line: position.line as u32, col: position.character as u32 };
             line_index.index.to_utf8(line_col)
diff --git a/src/tools/rust-analyzer/crates/rust-analyzer/src/global_state.rs b/src/tools/rust-analyzer/crates/rust-analyzer/src/global_state.rs
index 000ff88e458f..74277ff2e576 100644
--- a/src/tools/rust-analyzer/crates/rust-analyzer/src/global_state.rs
+++ b/src/tools/rust-analyzer/crates/rust-analyzer/src/global_state.rs
@@ -64,7 +64,7 @@ pub(crate) struct GlobalState {
     pub(crate) source_root_config: SourceRootConfig,
     pub(crate) proc_macro_clients: Vec<Result<ProcMacroServer, String>>,
 
-    pub(crate) flycheck: Vec<FlycheckHandle>,
+    pub(crate) flycheck: Arc<[FlycheckHandle]>,
     pub(crate) flycheck_sender: Sender<flycheck::Message>,
     pub(crate) flycheck_receiver: Receiver<flycheck::Message>,
 
@@ -117,6 +117,7 @@ pub(crate) struct GlobalStateSnapshot {
     vfs: Arc<RwLock<(vfs::Vfs, NoHashHashMap<FileId, LineEndings>)>>,
     pub(crate) workspaces: Arc<Vec<ProjectWorkspace>>,
     pub(crate) proc_macros_loaded: bool,
+    pub(crate) flycheck: Arc<[FlycheckHandle]>,
 }
 
 impl std::panic::UnwindSafe for GlobalStateSnapshot {}
@@ -155,7 +156,7 @@ impl GlobalState {
             source_root_config: SourceRootConfig::default(),
             proc_macro_clients: vec![],
 
-            flycheck: Vec::new(),
+            flycheck: Arc::new([]),
             flycheck_sender,
             flycheck_receiver,
 
@@ -295,6 +296,7 @@ impl GlobalState {
             mem_docs: self.mem_docs.clone(),
             semantic_tokens_cache: Arc::clone(&self.semantic_tokens_cache),
             proc_macros_loaded: !self.fetch_build_data_queue.last_op_result().0.is_empty(),
+            flycheck: self.flycheck.clone(),
         }
     }
 
@@ -381,7 +383,7 @@ impl GlobalStateSnapshot {
     pub(crate) fn file_line_index(&self, file_id: FileId) -> Cancellable<LineIndex> {
         let endings = self.vfs.read().1[&file_id];
         let index = self.analysis.file_line_index(file_id)?;
-        let res = LineIndex { index, endings, encoding: self.config.offset_encoding() };
+        let res = LineIndex { index, endings, encoding: self.config.position_encoding() };
         Ok(res)
     }
 
@@ -398,6 +400,10 @@ impl GlobalStateSnapshot {
         url_from_abs_path(path)
     }
 
+    pub(crate) fn file_id_to_file_path(&self, file_id: FileId) -> vfs::VfsPath {
+        self.vfs.read().0.file_path(file_id)
+    }
+
     pub(crate) fn cargo_target_for_crate_root(
         &self,
         crate_id: CrateId,
diff --git a/src/tools/rust-analyzer/crates/rust-analyzer/src/handlers.rs b/src/tools/rust-analyzer/crates/rust-analyzer/src/handlers.rs
index 8c3ea77d0611..34795a8eb40a 100644
--- a/src/tools/rust-analyzer/crates/rust-analyzer/src/handlers.rs
+++ b/src/tools/rust-analyzer/crates/rust-analyzer/src/handlers.rs
@@ -658,7 +658,7 @@ pub(crate) fn handle_parent_module(
 
         // check if invoked at the crate root
         let file_id = from_proto::file_id(&snap, &params.text_document.uri)?;
-        let crate_id = match snap.analysis.crate_for(file_id)?.first() {
+        let crate_id = match snap.analysis.crates_for(file_id)?.first() {
             Some(&crate_id) => crate_id,
             None => return Ok(None),
         };
@@ -1782,7 +1782,15 @@ fn run_rustfmt(
 ) -> Result<Option<Vec<lsp_types::TextEdit>>> {
     let file_id = from_proto::file_id(snap, &text_document.uri)?;
     let file = snap.analysis.file_text(file_id)?;
-    let crate_ids = snap.analysis.crate_for(file_id)?;
+
+    // find the edition of the package the file belongs to
+    // (if it belongs to multiple we'll just pick the first one and pray)
+    let edition = snap
+        .analysis
+        .relevant_crates_for(file_id)?
+        .into_iter()
+        .find_map(|crate_id| snap.cargo_target_for_crate_root(crate_id))
+        .map(|(ws, target)| ws[ws[target].package].edition);
 
     let line_index = snap.file_line_index(file_id)?;
 
@@ -1808,9 +1816,7 @@ fn run_rustfmt(
                     );
                 }
             }
-            if let Some(&crate_id) = crate_ids.first() {
-                // Assume all crates are in the same edition
-                let edition = snap.analysis.crate_edition(crate_id)?;
+            if let Some(edition) = edition {
                 cmd.arg("--edition");
                 cmd.arg(edition.to_string());
             }
diff --git a/src/tools/rust-analyzer/crates/rust-analyzer/src/line_index.rs b/src/tools/rust-analyzer/crates/rust-analyzer/src/line_index.rs
index c116414da01d..0d424b915703 100644
--- a/src/tools/rust-analyzer/crates/rust-analyzer/src/line_index.rs
+++ b/src/tools/rust-analyzer/crates/rust-analyzer/src/line_index.rs
@@ -7,7 +7,7 @@
 
 use std::sync::Arc;
 
-pub enum OffsetEncoding {
+pub enum PositionEncoding {
     Utf8,
     Utf16,
 }
@@ -15,7 +15,7 @@ pub enum OffsetEncoding {
 pub(crate) struct LineIndex {
     pub(crate) index: Arc<ide::LineIndex>,
     pub(crate) endings: LineEndings,
-    pub(crate) encoding: OffsetEncoding,
+    pub(crate) encoding: PositionEncoding,
 }
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
diff --git a/src/tools/rust-analyzer/crates/rust-analyzer/src/lsp_ext.rs b/src/tools/rust-analyzer/crates/rust-analyzer/src/lsp_ext.rs
index e61c8b643d2d..8cc5648f3ce0 100644
--- a/src/tools/rust-analyzer/crates/rust-analyzer/src/lsp_ext.rs
+++ b/src/tools/rust-analyzer/crates/rust-analyzer/src/lsp_ext.rs
@@ -3,6 +3,7 @@
 use std::{collections::HashMap, path::PathBuf};
 
 use lsp_types::request::Request;
+use lsp_types::PositionEncodingKind;
 use lsp_types::{
     notification::Notification, CodeActionKind, DocumentOnTypeFormattingParams,
     PartialResultParams, Position, Range, TextDocumentIdentifier, WorkDoneProgressParams,
@@ -455,7 +456,15 @@ pub(crate) enum CodeLensResolveData {
 }
 
 pub fn supports_utf8(caps: &lsp_types::ClientCapabilities) -> bool {
-    caps.offset_encoding.as_deref().unwrap_or_default().iter().any(|it| it == "utf-8")
+    match &caps.general {
+        Some(general) => general
+            .position_encodings
+            .as_deref()
+            .unwrap_or_default()
+            .iter()
+            .any(|it| it == &PositionEncodingKind::UTF8),
+        _ => false,
+    }
 }
 
 pub enum MoveItem {}
diff --git a/src/tools/rust-analyzer/crates/rust-analyzer/src/lsp_utils.rs b/src/tools/rust-analyzer/crates/rust-analyzer/src/lsp_utils.rs
index 5a37cbe2e334..c6a4db9a453a 100644
--- a/src/tools/rust-analyzer/crates/rust-analyzer/src/lsp_utils.rs
+++ b/src/tools/rust-analyzer/crates/rust-analyzer/src/lsp_utils.rs
@@ -6,7 +6,7 @@ use lsp_server::Notification;
 use crate::{
     from_proto,
     global_state::GlobalState,
-    line_index::{LineEndings, LineIndex, OffsetEncoding},
+    line_index::{LineEndings, LineIndex, PositionEncoding},
     LspError,
 };
 
@@ -87,6 +87,7 @@ impl GlobalState {
         state: Progress,
         message: Option<String>,
         fraction: Option<f64>,
+        cancel_token: Option<String>,
     ) {
         if !self.config.work_done_progress() {
             return;
@@ -95,7 +96,10 @@ impl GlobalState {
             assert!((0.0..=1.0).contains(&f));
             (f * 100.0) as u32
         });
-        let token = lsp_types::ProgressToken::String(format!("rustAnalyzer/{}", title));
+        let cancellable = Some(cancel_token.is_some());
+        let token = lsp_types::ProgressToken::String(
+            cancel_token.unwrap_or_else(|| format!("rustAnalyzer/{}", title)),
+        );
         let work_done_progress = match state {
             Progress::Begin => {
                 self.send_request::<lsp_types::request::WorkDoneProgressCreate>(
@@ -105,14 +109,14 @@ impl GlobalState {
 
                 lsp_types::WorkDoneProgress::Begin(lsp_types::WorkDoneProgressBegin {
                     title: title.into(),
-                    cancellable: None,
+                    cancellable,
                     message,
                     percentage,
                 })
             }
             Progress::Report => {
                 lsp_types::WorkDoneProgress::Report(lsp_types::WorkDoneProgressReport {
-                    cancellable: None,
+                    cancellable,
                     message,
                     percentage,
                 })
@@ -136,7 +140,7 @@ pub(crate) fn apply_document_changes(
         index: Arc::new(ide::LineIndex::new(old_text)),
         // We don't care about line endings or offset encoding here.
         endings: LineEndings::Unix,
-        encoding: OffsetEncoding::Utf16,
+        encoding: PositionEncoding::Utf16,
     };
 
     // The changes we got must be applied sequentially, but can cross lines so we
diff --git a/src/tools/rust-analyzer/crates/rust-analyzer/src/main_loop.rs b/src/tools/rust-analyzer/crates/rust-analyzer/src/main_loop.rs
index 15922dac651c..7d10dc5d15b6 100644
--- a/src/tools/rust-analyzer/crates/rust-analyzer/src/main_loop.rs
+++ b/src/tools/rust-analyzer/crates/rust-analyzer/src/main_loop.rs
@@ -10,7 +10,7 @@ use std::{
 use always_assert::always;
 use crossbeam_channel::{select, Receiver};
 use flycheck::FlycheckHandle;
-use ide_db::base_db::{SourceDatabase, SourceDatabaseExt, VfsPath};
+use ide_db::base_db::{SourceDatabaseExt, VfsPath};
 use itertools::Itertools;
 use lsp_server::{Connection, Notification, Request};
 use lsp_types::notification::Notification as _;
@@ -191,7 +191,7 @@ impl GlobalState {
         // NOTE: don't count blocking select! call as a loop-turn time
         let _p = profile::span("GlobalState::handle_event");
 
-        tracing::debug!("handle_event({:?})", event);
+        tracing::debug!("{:?} handle_event({:?})", loop_start, event);
         let task_queue_len = self.task_pool.handle.len();
         if task_queue_len > 0 {
             tracing::info!("task queue len: {}", task_queue_len);
@@ -257,7 +257,7 @@ impl GlobalState {
                         }
                     };
 
-                    self.report_progress("Indexing", state, message, Some(fraction));
+                    self.report_progress("Indexing", state, message, Some(fraction), None);
                 }
             }
             Event::Vfs(message) => {
@@ -465,7 +465,7 @@ impl GlobalState {
                     }
                 };
 
-                self.report_progress("Fetching", state, msg, None);
+                self.report_progress("Fetching", state, msg, None, None);
             }
             Task::FetchBuildData(progress) => {
                 let (state, msg) = match progress {
@@ -481,7 +481,7 @@ impl GlobalState {
                 };
 
                 if let Some(state) = state {
-                    self.report_progress("Loading", state, msg, None);
+                    self.report_progress("Loading", state, msg, None, None);
                 }
             }
         }
@@ -518,6 +518,7 @@ impl GlobalState {
                     state,
                     Some(format!("{}/{}", n_done, n_total)),
                     Some(Progress::fraction(n_done, n_total)),
+                    None,
                 )
             }
         }
@@ -542,7 +543,10 @@ impl GlobalState {
                             diag.fix,
                         ),
                         Err(err) => {
-                            tracing::error!("File with cargo diagnostic not found in VFS: {}", err);
+                            tracing::error!(
+                                "flycheck {id}: File with cargo diagnostic not found in VFS: {}",
+                                err
+                            );
                         }
                     };
                 }
@@ -584,7 +588,13 @@ impl GlobalState {
                 } else {
                     format!("cargo check (#{})", id + 1)
                 };
-                self.report_progress(&title, state, message, None);
+                self.report_progress(
+                    &title,
+                    state,
+                    message,
+                    None,
+                    Some(format!("rust-analyzer/checkOnSave/{}", id)),
+                );
             }
         }
     }
@@ -597,30 +607,34 @@ impl GlobalState {
 
     /// Handles a request.
     fn on_request(&mut self, req: Request) {
-        if self.shutdown_requested {
-            self.respond(lsp_server::Response::new_err(
-                req.id,
-                lsp_server::ErrorCode::InvalidRequest as i32,
-                "Shutdown already requested.".to_owned(),
-            ));
-            return;
+        let mut dispatcher = RequestDispatcher { req: Some(req), global_state: self };
+        dispatcher.on_sync_mut::<lsp_types::request::Shutdown>(|s, ()| {
+            s.shutdown_requested = true;
+            Ok(())
+        });
+
+        if let RequestDispatcher { req: Some(req), global_state: this } = &mut dispatcher {
+            if this.shutdown_requested {
+                this.respond(lsp_server::Response::new_err(
+                    req.id.clone(),
+                    lsp_server::ErrorCode::InvalidRequest as i32,
+                    "Shutdown already requested.".to_owned(),
+                ));
+                return;
+            }
+
+            // Avoid flashing a bunch of unresolved references during initial load.
+            if this.workspaces.is_empty() && !this.is_quiescent() {
+                this.respond(lsp_server::Response::new_err(
+                    req.id.clone(),
+                    lsp_server::ErrorCode::ContentModified as i32,
+                    "waiting for cargo metadata or cargo check".to_owned(),
+                ));
+                return;
+            }
         }
 
-        // Avoid flashing a bunch of unresolved references during initial load.
-        if self.workspaces.is_empty() && !self.is_quiescent() {
-            self.respond(lsp_server::Response::new_err(
-                req.id,
-                lsp_server::ErrorCode::ContentModified as i32,
-                "waiting for cargo metadata or cargo check".to_owned(),
-            ));
-            return;
-        }
-
-        RequestDispatcher { req: Some(req), global_state: self }
-            .on_sync_mut::<lsp_types::request::Shutdown>(|s, ()| {
-                s.shutdown_requested = true;
-                Ok(())
-            })
+        dispatcher
             .on_sync_mut::<lsp_ext::ReloadWorkspace>(handlers::handle_workspace_reload)
             .on_sync_mut::<lsp_ext::MemoryUsage>(handlers::handle_memory_usage)
             .on_sync_mut::<lsp_ext::ShuffleCrateGraph>(handlers::handle_shuffle_crate_graph)
@@ -698,7 +712,16 @@ impl GlobalState {
                 this.cancel(id);
                 Ok(())
             })?
-            .on::<lsp_types::notification::WorkDoneProgressCancel>(|_this, _params| {
+            .on::<lsp_types::notification::WorkDoneProgressCancel>(|this, params| {
+                if let lsp_types::NumberOrString::String(s) = &params.token {
+                    if let Some(id) = s.strip_prefix("rust-analyzer/checkOnSave/") {
+                        if let Ok(id) = u32::from_str_radix(id, 10) {
+                            if let Some(flycheck) = this.flycheck.get(id as usize) {
+                                flycheck.cancel();
+                            }
+                        }
+                    }
+                }
                 // Just ignore this. It is OK to continue sending progress
                 // notifications for this token, as the client can't know when
                 // we accepted notification.
@@ -711,7 +734,7 @@ impl GlobalState {
                         .insert(path.clone(), DocumentData::new(params.text_document.version))
                         .is_err();
                     if already_exists {
-                        tracing::error!("duplicate DidOpenTextDocument: {}", path)
+                        tracing::error!("duplicate DidOpenTextDocument: {}", path);
                     }
                     this.vfs
                         .write()
@@ -758,69 +781,7 @@ impl GlobalState {
                 Ok(())
             })?
             .on::<lsp_types::notification::DidSaveTextDocument>(|this, params| {
-                let mut updated = false;
                 if let Ok(vfs_path) = from_proto::vfs_path(&params.text_document.uri) {
-                    let (vfs, _) = &*this.vfs.read();
-
-                    // Trigger flychecks for all workspaces that depend on the saved file
-                    if let Some(file_id) = vfs.file_id(&vfs_path) {
-                        let analysis = this.analysis_host.analysis();
-                        // Crates containing or depending on the saved file
-                        let crate_ids: Vec<_> = analysis
-                            .crate_for(file_id)?
-                            .into_iter()
-                            .flat_map(|id| {
-                                this.analysis_host
-                                    .raw_database()
-                                    .crate_graph()
-                                    .transitive_rev_deps(id)
-                            })
-                            .sorted()
-                            .unique()
-                            .collect();
-
-                        let crate_root_paths: Vec<_> = crate_ids
-                            .iter()
-                            .filter_map(|&crate_id| {
-                                analysis
-                                    .crate_root(crate_id)
-                                    .map(|file_id| {
-                                        vfs.file_path(file_id).as_path().map(ToOwned::to_owned)
-                                    })
-                                    .transpose()
-                            })
-                            .collect::<ide::Cancellable<_>>()?;
-                        let crate_root_paths: Vec<_> =
-                            crate_root_paths.iter().map(Deref::deref).collect();
-
-                        // Find all workspaces that have at least one target containing the saved file
-                        let workspace_ids =
-                            this.workspaces.iter().enumerate().filter(|(_, ws)| match ws {
-                                project_model::ProjectWorkspace::Cargo { cargo, .. } => {
-                                    cargo.packages().any(|pkg| {
-                                        cargo[pkg].targets.iter().any(|&it| {
-                                            crate_root_paths.contains(&cargo[it].root.as_path())
-                                        })
-                                    })
-                                }
-                                project_model::ProjectWorkspace::Json { project, .. } => project
-                                    .crates()
-                                    .any(|(c, _)| crate_ids.iter().any(|&crate_id| crate_id == c)),
-                                project_model::ProjectWorkspace::DetachedFiles { .. } => false,
-                            });
-
-                        // Find and trigger corresponding flychecks
-                        for flycheck in &this.flycheck {
-                            for (id, _) in workspace_ids.clone() {
-                                if id == flycheck.id() {
-                                    updated = true;
-                                    flycheck.restart();
-                                    continue;
-                                }
-                            }
-                        }
-                    }
-
                     // Re-fetch workspaces if a workspace related file has changed
                     if let Some(abs_path) = vfs_path.as_path() {
                         if reload::should_refresh_for_change(&abs_path, ChangeKind::Modify) {
@@ -828,13 +789,90 @@ impl GlobalState {
                                 .request_op(format!("DidSaveTextDocument {}", abs_path.display()));
                         }
                     }
+
+                    let file_id = this.vfs.read().0.file_id(&vfs_path);
+                    if let Some(file_id) = file_id {
+                        let world = this.snapshot();
+                        let mut updated = false;
+                        let task = move || -> std::result::Result<(), ide::Cancelled> {
+                            // Trigger flychecks for all workspaces that depend on the saved file
+                            // Crates containing or depending on the saved file
+                            let crate_ids: Vec<_> = world
+                                .analysis
+                                .crates_for(file_id)?
+                                .into_iter()
+                                .flat_map(|id| world.analysis.transitive_rev_deps(id))
+                                .flatten()
+                                .sorted()
+                                .unique()
+                                .collect();
+
+                            let crate_root_paths: Vec<_> = crate_ids
+                                .iter()
+                                .filter_map(|&crate_id| {
+                                    world
+                                        .analysis
+                                        .crate_root(crate_id)
+                                        .map(|file_id| {
+                                            world
+                                                .file_id_to_file_path(file_id)
+                                                .as_path()
+                                                .map(ToOwned::to_owned)
+                                        })
+                                        .transpose()
+                                })
+                                .collect::<ide::Cancellable<_>>()?;
+                            let crate_root_paths: Vec<_> =
+                                crate_root_paths.iter().map(Deref::deref).collect();
+
+                            // Find all workspaces that have at least one target containing the saved file
+                            let workspace_ids =
+                                world.workspaces.iter().enumerate().filter(|(_, ws)| match ws {
+                                    project_model::ProjectWorkspace::Cargo { cargo, .. } => {
+                                        cargo.packages().any(|pkg| {
+                                            cargo[pkg].targets.iter().any(|&it| {
+                                                crate_root_paths.contains(&cargo[it].root.as_path())
+                                            })
+                                        })
+                                    }
+                                    project_model::ProjectWorkspace::Json { project, .. } => {
+                                        project.crates().any(|(c, _)| {
+                                            crate_ids.iter().any(|&crate_id| crate_id == c)
+                                        })
+                                    }
+                                    project_model::ProjectWorkspace::DetachedFiles { .. } => false,
+                                });
+
+                            // Find and trigger corresponding flychecks
+                            for flycheck in world.flycheck.iter() {
+                                for (id, _) in workspace_ids.clone() {
+                                    if id == flycheck.id() {
+                                        updated = true;
+                                        flycheck.restart();
+                                        continue;
+                                    }
+                                }
+                            }
+                            // No specific flycheck was triggered, so let's trigger all of them.
+                            if !updated {
+                                for flycheck in world.flycheck.iter() {
+                                    flycheck.restart();
+                                }
+                            }
+                            Ok(())
+                        };
+                        this.task_pool.handle.spawn_with_sender(move |_| {
+                            if let Err(e) = std::panic::catch_unwind(task) {
+                                tracing::error!("DidSaveTextDocument flycheck task panicked: {e:?}")
+                            }
+                        });
+                        return Ok(());
+                    }
                 }
 
                 // No specific flycheck was triggered, so let's trigger all of them.
-                if !updated {
-                    for flycheck in &this.flycheck {
-                        flycheck.restart();
-                    }
+                for flycheck in this.flycheck.iter() {
+                    flycheck.restart();
                 }
                 Ok(())
             })?
diff --git a/src/tools/rust-analyzer/crates/rust-analyzer/src/reload.rs b/src/tools/rust-analyzer/crates/rust-analyzer/src/reload.rs
index f87348939446..e1f651786dee 100644
--- a/src/tools/rust-analyzer/crates/rust-analyzer/src/reload.rs
+++ b/src/tools/rust-analyzer/crates/rust-analyzer/src/reload.rs
@@ -175,10 +175,8 @@ impl GlobalState {
                     sender.send(Task::FetchBuildData(BuildDataProgress::Report(msg))).unwrap()
                 }
             };
-            let mut res = Vec::new();
-            for ws in workspaces.iter() {
-                res.push(ws.run_build_scripts(&config, &progress));
-            }
+            let res = ProjectWorkspace::run_all_build_scripts(&workspaces, &config, &progress);
+
             sender.send(Task::FetchBuildData(BuildDataProgress::End((workspaces, res)))).unwrap();
         });
     }
@@ -468,39 +466,54 @@ impl GlobalState {
         let config = match self.config.flycheck() {
             Some(it) => it,
             None => {
-                self.flycheck = Vec::new();
+                self.flycheck = Arc::new([]);
                 self.diagnostics.clear_check_all();
                 return;
             }
         };
 
         let sender = self.flycheck_sender.clone();
-        self.flycheck = self
-            .workspaces
-            .iter()
-            .enumerate()
-            .filter_map(|(id, w)| match w {
-                ProjectWorkspace::Cargo { cargo, .. } => Some((id, cargo.workspace_root())),
-                ProjectWorkspace::Json { project, .. } => {
-                    // Enable flychecks for json projects if a custom flycheck command was supplied
-                    // in the workspace configuration.
-                    match config {
-                        FlycheckConfig::CustomCommand { .. } => Some((id, project.path())),
-                        _ => None,
-                    }
-                }
-                ProjectWorkspace::DetachedFiles { .. } => None,
-            })
-            .map(|(id, root)| {
-                let sender = sender.clone();
-                FlycheckHandle::spawn(
-                    id,
-                    Box::new(move |msg| sender.send(msg).unwrap()),
-                    config.clone(),
-                    root.to_path_buf(),
-                )
-            })
-            .collect();
+        let invocation_strategy = match config {
+            FlycheckConfig::CargoCommand { .. } => flycheck::InvocationStrategy::PerWorkspace,
+            FlycheckConfig::CustomCommand { invocation_strategy, .. } => invocation_strategy,
+        };
+
+        self.flycheck = match invocation_strategy {
+            flycheck::InvocationStrategy::Once => vec![FlycheckHandle::spawn(
+                0,
+                Box::new(move |msg| sender.send(msg).unwrap()),
+                config.clone(),
+                self.config.root_path().clone(),
+            )],
+            flycheck::InvocationStrategy::PerWorkspace => {
+                self.workspaces
+                    .iter()
+                    .enumerate()
+                    .filter_map(|(id, w)| match w {
+                        ProjectWorkspace::Cargo { cargo, .. } => Some((id, cargo.workspace_root())),
+                        ProjectWorkspace::Json { project, .. } => {
+                            // Enable flychecks for json projects if a custom flycheck command was supplied
+                            // in the workspace configuration.
+                            match config {
+                                FlycheckConfig::CustomCommand { .. } => Some((id, project.path())),
+                                _ => None,
+                            }
+                        }
+                        ProjectWorkspace::DetachedFiles { .. } => None,
+                    })
+                    .map(|(id, root)| {
+                        let sender = sender.clone();
+                        FlycheckHandle::spawn(
+                            id,
+                            Box::new(move |msg| sender.send(msg).unwrap()),
+                            config.clone(),
+                            root.to_path_buf(),
+                        )
+                    })
+                    .collect()
+            }
+        }
+        .into();
     }
 }
 
diff --git a/src/tools/rust-analyzer/crates/rust-analyzer/src/to_proto.rs b/src/tools/rust-analyzer/crates/rust-analyzer/src/to_proto.rs
index 5936454a7c54..6c84a2069cd5 100644
--- a/src/tools/rust-analyzer/crates/rust-analyzer/src/to_proto.rs
+++ b/src/tools/rust-analyzer/crates/rust-analyzer/src/to_proto.rs
@@ -21,7 +21,7 @@ use crate::{
     cargo_target_spec::CargoTargetSpec,
     config::{CallInfoConfig, Config},
     global_state::GlobalStateSnapshot,
-    line_index::{LineEndings, LineIndex, OffsetEncoding},
+    line_index::{LineEndings, LineIndex, PositionEncoding},
     lsp_ext,
     lsp_utils::invalid_params_error,
     semantic_tokens, Result,
@@ -30,8 +30,8 @@ use crate::{
 pub(crate) fn position(line_index: &LineIndex, offset: TextSize) -> lsp_types::Position {
     let line_col = line_index.index.line_col(offset);
     match line_index.encoding {
-        OffsetEncoding::Utf8 => lsp_types::Position::new(line_col.line, line_col.col),
-        OffsetEncoding::Utf16 => {
+        PositionEncoding::Utf8 => lsp_types::Position::new(line_col.line, line_col.col),
+        PositionEncoding::Utf16 => {
             let line_col = line_index.index.to_utf16(line_col);
             lsp_types::Position::new(line_col.line, line_col.col)
         }
@@ -1394,7 +1394,7 @@ fn main() {
         let line_index = LineIndex {
             index: Arc::new(ide::LineIndex::new(text)),
             endings: LineEndings::Unix,
-            encoding: OffsetEncoding::Utf16,
+            encoding: PositionEncoding::Utf16,
         };
         let converted: Vec<lsp_types::FoldingRange> =
             folds.into_iter().map(|it| folding_range(text, &line_index, true, it)).collect();
diff --git a/src/tools/rust-analyzer/crates/syntax/rust.ungram b/src/tools/rust-analyzer/crates/syntax/rust.ungram
index 894795435451..5379732ac6c3 100644
--- a/src/tools/rust-analyzer/crates/syntax/rust.ungram
+++ b/src/tools/rust-analyzer/crates/syntax/rust.ungram
@@ -51,7 +51,7 @@ TypeArg =
   Type
 
 AssocTypeArg =
-  NameRef GenericParamList? (':' TypeBoundList | ('=' Type | ConstArg))
+  NameRef GenericArgList? (':' TypeBoundList | ('=' Type | ConstArg))
 
 LifetimeArg =
   Lifetime
diff --git a/src/tools/rust-analyzer/crates/syntax/src/ast/edit_in_place.rs b/src/tools/rust-analyzer/crates/syntax/src/ast/edit_in_place.rs
index 229e7419b736..660c057e99c5 100644
--- a/src/tools/rust-analyzer/crates/syntax/src/ast/edit_in_place.rs
+++ b/src/tools/rust-analyzer/crates/syntax/src/ast/edit_in_place.rs
@@ -645,7 +645,7 @@ impl ast::RecordPatFieldList {
 }
 
 fn get_or_insert_comma_after(syntax: &SyntaxNode) -> SyntaxToken {
-    let comma = match syntax
+    match syntax
         .siblings_with_tokens(Direction::Next)
         .filter_map(|it| it.into_token())
         .find(|it| it.kind() == T![,])
@@ -656,8 +656,7 @@ fn get_or_insert_comma_after(syntax: &SyntaxNode) -> SyntaxToken {
             ted::insert(Position::after(syntax), &comma);
             comma
         }
-    };
-    comma
+    }
 }
 
 impl ast::StmtList {
diff --git a/src/tools/rust-analyzer/crates/syntax/src/ast/generated/nodes.rs b/src/tools/rust-analyzer/crates/syntax/src/ast/generated/nodes.rs
index 449402e5f5b3..6cfb98d92fcf 100644
--- a/src/tools/rust-analyzer/crates/syntax/src/ast/generated/nodes.rs
+++ b/src/tools/rust-analyzer/crates/syntax/src/ast/generated/nodes.rs
@@ -120,7 +120,7 @@ pub struct AssocTypeArg {
 impl ast::HasTypeBounds for AssocTypeArg {}
 impl AssocTypeArg {
     pub fn name_ref(&self) -> Option<NameRef> { support::child(&self.syntax) }
-    pub fn generic_param_list(&self) -> Option<GenericParamList> { support::child(&self.syntax) }
+    pub fn generic_arg_list(&self) -> Option<GenericArgList> { support::child(&self.syntax) }
     pub fn eq_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![=]) }
     pub fn ty(&self) -> Option<Type> { support::child(&self.syntax) }
     pub fn const_arg(&self) -> Option<ConstArg> { support::child(&self.syntax) }
@@ -142,16 +142,6 @@ impl ConstArg {
     pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
 }
 
-#[derive(Debug, Clone, PartialEq, Eq, Hash)]
-pub struct GenericParamList {
-    pub(crate) syntax: SyntaxNode,
-}
-impl GenericParamList {
-    pub fn l_angle_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![<]) }
-    pub fn generic_params(&self) -> AstChildren<GenericParam> { support::children(&self.syntax) }
-    pub fn r_angle_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![>]) }
-}
-
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct TypeBoundList {
     pub(crate) syntax: SyntaxNode,
@@ -527,6 +517,16 @@ impl Abi {
     pub fn extern_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![extern]) }
 }
 
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct GenericParamList {
+    pub(crate) syntax: SyntaxNode,
+}
+impl GenericParamList {
+    pub fn l_angle_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![<]) }
+    pub fn generic_params(&self) -> AstChildren<GenericParam> { support::children(&self.syntax) }
+    pub fn r_angle_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![>]) }
+}
+
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct WhereClause {
     pub(crate) syntax: SyntaxNode,
@@ -1834,17 +1834,6 @@ impl AstNode for ConstArg {
     }
     fn syntax(&self) -> &SyntaxNode { &self.syntax }
 }
-impl AstNode for GenericParamList {
-    fn can_cast(kind: SyntaxKind) -> bool { kind == GENERIC_PARAM_LIST }
-    fn cast(syntax: SyntaxNode) -> Option<Self> {
-        if Self::can_cast(syntax.kind()) {
-            Some(Self { syntax })
-        } else {
-            None
-        }
-    }
-    fn syntax(&self) -> &SyntaxNode { &self.syntax }
-}
 impl AstNode for TypeBoundList {
     fn can_cast(kind: SyntaxKind) -> bool { kind == TYPE_BOUND_LIST }
     fn cast(syntax: SyntaxNode) -> Option<Self> {
@@ -2153,6 +2142,17 @@ impl AstNode for Abi {
     }
     fn syntax(&self) -> &SyntaxNode { &self.syntax }
 }
+impl AstNode for GenericParamList {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == GENERIC_PARAM_LIST }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
 impl AstNode for WhereClause {
     fn can_cast(kind: SyntaxKind) -> bool { kind == WHERE_CLAUSE }
     fn cast(syntax: SyntaxNode) -> Option<Self> {
@@ -4263,11 +4263,6 @@ impl std::fmt::Display for ConstArg {
         std::fmt::Display::fmt(self.syntax(), f)
     }
 }
-impl std::fmt::Display for GenericParamList {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        std::fmt::Display::fmt(self.syntax(), f)
-    }
-}
 impl std::fmt::Display for TypeBoundList {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         std::fmt::Display::fmt(self.syntax(), f)
@@ -4408,6 +4403,11 @@ impl std::fmt::Display for Abi {
         std::fmt::Display::fmt(self.syntax(), f)
     }
 }
+impl std::fmt::Display for GenericParamList {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl std::fmt::Display for WhereClause {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         std::fmt::Display::fmt(self.syntax(), f)
diff --git a/src/tools/rust-analyzer/crates/syntax/src/ast/make.rs b/src/tools/rust-analyzer/crates/syntax/src/ast/make.rs
index 4057a75e7c1e..8c26009add2b 100644
--- a/src/tools/rust-analyzer/crates/syntax/src/ast/make.rs
+++ b/src/tools/rust-analyzer/crates/syntax/src/ast/make.rs
@@ -334,6 +334,10 @@ pub fn block_expr(
     ast_from_text(&format!("fn f() {buf}"))
 }
 
+pub fn tail_only_block_expr(tail_expr: ast::Expr) -> ast::BlockExpr {
+    ast_from_text(&format!("fn f() {{ {tail_expr} }}"))
+}
+
 /// Ideally this function wouldn't exist since it involves manual indenting.
 /// It differs from `make::block_expr` by also supporting comments.
 ///
@@ -656,6 +660,22 @@ pub fn let_stmt(
     };
     ast_from_text(&format!("fn f() {{ {text} }}"))
 }
+
+pub fn let_else_stmt(
+    pattern: ast::Pat,
+    ty: Option<ast::Type>,
+    expr: ast::Expr,
+    diverging: ast::BlockExpr,
+) -> ast::LetStmt {
+    let mut text = String::new();
+    format_to!(text, "let {pattern}");
+    if let Some(ty) = ty {
+        format_to!(text, ": {ty}");
+    }
+    format_to!(text, " = {expr} else {diverging};");
+    ast_from_text(&format!("fn f() {{ {text} }}"))
+}
+
 pub fn expr_stmt(expr: ast::Expr) -> ast::ExprStmt {
     let semi = if expr.is_block_like() { "" } else { ";" };
     ast_from_text(&format!("fn f() {{ {expr}{semi} (); }}"))
diff --git a/src/tools/rust-analyzer/crates/syntax/src/lib.rs b/src/tools/rust-analyzer/crates/syntax/src/lib.rs
index 4f5e273a520a..84c66b27e69f 100644
--- a/src/tools/rust-analyzer/crates/syntax/src/lib.rs
+++ b/src/tools/rust-analyzer/crates/syntax/src/lib.rs
@@ -92,7 +92,7 @@ impl<T> Parse<T> {
         SyntaxNode::new_root(self.green.clone())
     }
     pub fn errors(&self) -> &[SyntaxError] {
-        &*self.errors
+        &self.errors
     }
 }
 
diff --git a/src/tools/rust-analyzer/crates/syntax/src/validation.rs b/src/tools/rust-analyzer/crates/syntax/src/validation.rs
index b9f2b5132353..1eea2346451d 100644
--- a/src/tools/rust-analyzer/crates/syntax/src/validation.rs
+++ b/src/tools/rust-analyzer/crates/syntax/src/validation.rs
@@ -5,9 +5,7 @@
 mod block;
 
 use rowan::Direction;
-use rustc_lexer::unescape::{
-    self, unescape_byte, unescape_byte_literal, unescape_char, unescape_literal, Mode,
-};
+use rustc_lexer::unescape::{self, unescape_byte, unescape_char, unescape_literal, Mode};
 
 use crate::{
     algo,
@@ -143,7 +141,7 @@ fn validate_literal(literal: ast::Literal, acc: &mut Vec<SyntaxError>) {
         ast::LiteralKind::ByteString(s) => {
             if !s.is_raw() {
                 if let Some(without_quotes) = unquote(text, 2, '"') {
-                    unescape_byte_literal(without_quotes, Mode::ByteStr, &mut |range, char| {
+                    unescape_literal(without_quotes, Mode::ByteStr, &mut |range, char| {
                         if let Err(err) = char {
                             push_err(2, (range.start, err));
                         }
diff --git a/src/tools/rust-analyzer/crates/test-utils/src/minicore.rs b/src/tools/rust-analyzer/crates/test-utils/src/minicore.rs
index 59b1c147d7f1..69d2e62b2567 100644
--- a/src/tools/rust-analyzer/crates/test-utils/src/minicore.rs
+++ b/src/tools/rust-analyzer/crates/test-utils/src/minicore.rs
@@ -27,7 +27,6 @@
 //!     generator: pin
 //!     hash:
 //!     index: sized
-//!     infallible:
 //!     iterator: option
 //!     iterators: iterator, fn
 //!     option:
@@ -37,7 +36,7 @@
 //!     result:
 //!     sized:
 //!     slice:
-//!     try: infallible
+//!     try:
 //!     unsize: sized
 
 pub mod marker {
@@ -151,9 +150,6 @@ pub mod convert {
         fn as_ref(&self) -> &T;
     }
     // endregion:as_ref
-    // region:infallible
-    pub enum Infallible {}
-    // endregion:infallible
 }
 
 pub mod ops {
@@ -330,7 +326,7 @@ pub mod ops {
             Continue(C),
             Break(B),
         }
-        pub trait FromResidual<R = <Self as Try>::Residual> {
+        pub trait FromResidual<R = Self::Residual> {
             #[lang = "from_residual"]
             fn from_residual(residual: R) -> Self;
         }
@@ -346,13 +342,13 @@ pub mod ops {
 
         impl<B, C> Try for ControlFlow<B, C> {
             type Output = C;
-            type Residual = ControlFlow<B, crate::convert::Infallible>;
+            type Residual = ControlFlow<B, convert::Infallible>;
             fn from_output(output: Self::Output) -> Self {}
             fn branch(self) -> ControlFlow<Self::Residual, Self::Output> {}
         }
 
         impl<B, C> FromResidual for ControlFlow<B, C> {
-            fn from_residual(residual: ControlFlow<B, crate::convert::Infallible>) -> Self {}
+            fn from_residual(residual: ControlFlow<B, convert::Infallible>) -> Self {}
         }
     }
     pub use self::try_::{ControlFlow, FromResidual, Try};
@@ -473,33 +469,6 @@ pub mod option {
             }
         }
     }
-    // region:try
-    impl<T> crate::ops::Try for Option<T> {
-        type Output = T;
-        type Residual = Option<crate::convert::Infallible>;
-
-        #[inline]
-        fn from_output(output: Self::Output) -> Self {
-            Some(output)
-        }
-
-        #[inline]
-        fn branch(self) -> crate::ops::ControlFlow<Self::Residual, Self::Output> {
-            match self {
-                Some(v) => crate::ops::ControlFlow::Continue(v),
-                None => crate::ops::ControlFlow::Break(None),
-            }
-        }
-    }
-    impl<T> crate::ops::FromResidual for Option<T> {
-        #[inline]
-        fn from_residual(residual: Option<crate::convert::Infallible>) -> Self {
-            match residual {
-                None => None,
-            }
-        }
-    }
-    // endregion:try
 }
 // endregion:option
 
diff --git a/src/tools/rust-analyzer/docs/dev/architecture.md b/src/tools/rust-analyzer/docs/dev/architecture.md
index c173a239feab..e3a4fdfda90c 100644
--- a/src/tools/rust-analyzer/docs/dev/architecture.md
+++ b/src/tools/rust-analyzer/docs/dev/architecture.md
@@ -479,7 +479,9 @@ It is not cheap enough to enable in prod, and this is a bug which should be fixe
 ### Configurability
 
 rust-analyzer strives to be as configurable as possible while offering reasonable defaults where no configuration exists yet.
+The rule of thumb is to enable most features by default unless they are buggy or degrade performance too much.
 There will always be features that some people find more annoying than helpful, so giving the users the ability to tweak or disable these is a big part of offering a good user experience.
+Enabling them by default is a matter of discoverability, as many users end up don't know about some features even though they are presented in the manual.
 Mind the code--architecture gap: at the moment, we are using fewer feature flags than we really should.
 
 ### Serialization
diff --git a/src/tools/rust-analyzer/docs/dev/guide.md b/src/tools/rust-analyzer/docs/dev/guide.md
index 52a13da31c5d..56a68ef04379 100644
--- a/src/tools/rust-analyzer/docs/dev/guide.md
+++ b/src/tools/rust-analyzer/docs/dev/guide.md
@@ -338,7 +338,7 @@ The algorithm for building a tree of modules is to start with a crate root
 declarations and recursively process child modules. This is handled by the
 [`module_tree_query`], with two slight variations.
 
-[`module_tree_query`]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/hir/src/module_tree.rs#L116-L123
+[`module_tree_query`]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_hir/src/module_tree.rs#L115-L133
 
 First, rust-analyzer builds a module tree for all crates in a source root
 simultaneously. The main reason for this is historical (`module_tree` predates
@@ -361,7 +361,7 @@ the same, we don't have to re-execute [`module_tree_query`]. In fact, we only
 need to re-execute it when we add/remove new files or when we change mod
 declarations.
 
-[`submodules_query`]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/hir/src/module_tree.rs#L41
+[`submodules_query`]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_hir/src/module_tree.rs#L41
 
 We store the resulting modules in a `Vec`-based indexed arena. The indices in
 the arena becomes module IDs. And this brings us to the next topic:
@@ -389,8 +389,8 @@ integers which can "intern" a location and return an integer ID back. The salsa
 database we use includes a couple of [interners]. How to "garbage collect"
 unused locations is an open question.
 
-[`LocationInterner`]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/base_db/src/loc2id.rs#L65-L71
-[interners]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/hir/src/db.rs#L22-L23
+[`LocationInterner`]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_db/src/loc2id.rs#L65-L71
+[interners]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_hir/src/db.rs#L22-L23
 
 For example, we use `LocationInterner` to assign IDs to definitions of functions,
 structs, enums, etc. The location, [`DefLoc`] contains two bits of information:
@@ -404,7 +404,7 @@ using offsets, text ranges or syntax trees as keys and values for queries. What
 we do instead is we store "index" of the item among all of the items of a file
 (so, a positional based ID, but localized to a single file).
 
-[`DefLoc`]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/hir/src/ids.rs#L127-L139
+[`DefLoc`]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_hir/src/ids.rs#L129-L139
 
 One thing we've glossed over for the time being is support for macros. We have
 only proof of concept handling of macros at the moment, but they are extremely
@@ -437,7 +437,7 @@ terms of `HirFileId`! This does not recur infinitely though: any chain of
 `HirFileId`s bottoms out in `HirFileId::FileId`, that is, some source file
 actually written by the user.
 
-[`HirFileId`]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/hir/src/ids.rs#L18-L125
+[`HirFileId`]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_hir/src/ids.rs#L31-L93
 
 Now that we understand how to identify a definition, in a source or in a
 macro-generated file, we can discuss name resolution a bit.
@@ -451,14 +451,13 @@ each module into a position-independent representation which does not change if
 we modify bodies of the items. After that we [loop] resolving all imports until
 we've reached a fixed point.
 
-[lower]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/hir/src/nameres/lower.rs#L113-L117
-[loop]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/hir/src/nameres.rs#L186-L196
-
+[lower]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_hir/src/nameres/lower.rs#L113-L147
+[loop]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_hir/src/nameres.rs#L186-L196
 And, given all our preparation with IDs and a position-independent representation,
 it is satisfying to [test] that typing inside function body does not invalidate
 name resolution results.
 
-[test]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/hir/src/nameres/tests.rs#L376
+[test]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_hir/src/nameres/tests.rs#L376
 
 An interesting fact about name resolution is that it "erases" all of the
 intermediate paths from the imports: in the end, we know which items are defined
@@ -493,10 +492,10 @@ there's an intermediate [projection query] which returns only the first
 position-independent part of the lowering. The result of this query is stable.
 Naturally, name resolution [uses] this stable projection query.
 
-[imports]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/hir/src/nameres/lower.rs#L52-L59
-[`SourceMap`]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/hir/src/nameres/lower.rs#L52-L59
-[projection query]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/hir/src/nameres/lower.rs#L97-L103
-[uses]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/hir/src/query_definitions.rs#L49
+[imports]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_hir/src/nameres/lower.rs#L52-L59
+[`SourceMap`]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_hir/src/nameres/lower.rs#L52-L59
+[projection query]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_hir/src/nameres/lower.rs#L97-L103
+[uses]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_hir/src/query_definitions.rs#L49
 
 ## Type inference
 
@@ -518,10 +517,10 @@ construct a mapping from `ExprId`s to types.
 
 [@flodiebold]: https://github.com/flodiebold
 [#327]: https://github.com/rust-lang/rust-analyzer/pull/327
-[lower the AST]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/hir/src/expr.rs
-[positional ID]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/hir/src/expr.rs#L13-L15
-[a source map]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/hir/src/expr.rs#L41-L44
-[type inference]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/hir/src/ty.rs#L1208-L1223
+[lower the AST]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_hir/src/expr.rs
+[positional ID]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_hir/src/expr.rs#L13-L15
+[a source map]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_hir/src/expr.rs#L41-L44
+[type inference]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_hir/src/ty.rs#L1208-L1223
 
 ## Tying it all together: completion
 
@@ -563,10 +562,11 @@ the type to completion.
 [catch]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_lsp_server/src/main_loop.rs#L436-L442
 [the handler]: https://salsa.zulipchat.com/#narrow/stream/181542-rfcs.2Fsalsa-query-group/topic/design.20next.20steps
 [ask analysis for completion]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ide_api/src/lib.rs#L439-L444
-[completion implementation]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ide_api/src/completion.rs#L46-L62
-[`CompletionContext`]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ide_api/src/completion/completion_context.rs#L14-L37
-["IntelliJ Trick"]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ide_api/src/completion/completion_context.rs#L72-L75
-[find an ancestor `fn` node]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ide_api/src/completion/completion_context.rs#L116-L120
-[semantic model]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ide_api/src/completion/completion_context.rs#L123
-[series of independent completion routines]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ide_api/src/completion.rs#L52-L59
-[`complete_dot`]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ide_api/src/completion/complete_dot.rs#L6-L22
+[ask analysis for completion]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_ide_api/src/lib.rs#L439-L444
+[completion implementation]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_ide_api/src/completion.rs#L46-L62
+[`CompletionContext`]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_ide_api/src/completion/completion_context.rs#L14-L37
+["IntelliJ Trick"]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_ide_api/src/completion/completion_context.rs#L72-L75
+[find an ancestor `fn` node]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_ide_api/src/completion/completion_context.rs#L116-L120
+[semantic model]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_ide_api/src/completion/completion_context.rs#L123
+[series of independent completion routines]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_ide_api/src/completion.rs#L52-L59
+[`complete_dot`]: https://github.com/rust-lang/rust-analyzer/blob/guide-2019-01/crates/ra_ide_api/src/completion/complete_dot.rs#L6-L22
diff --git a/src/tools/rust-analyzer/docs/dev/lsp-extensions.md b/src/tools/rust-analyzer/docs/dev/lsp-extensions.md
index 6d2c7d7b0634..fe316fcae9b8 100644
--- a/src/tools/rust-analyzer/docs/dev/lsp-extensions.md
+++ b/src/tools/rust-analyzer/docs/dev/lsp-extensions.md
@@ -1,5 +1,5 @@
 <!---
-lsp_ext.rs hash: 7b710095d773b978
+lsp_ext.rs hash: 62068e53ac202dc8
 
 If you need to change the above hash to make the test pass, please check if you
 need to adjust this doc as well and ping this issue:
@@ -19,12 +19,6 @@ Requests, which are likely to always remain specific to `rust-analyzer` are unde
 
 If you want to be notified about the changes to this document, subscribe to [#4604](https://github.com/rust-lang/rust-analyzer/issues/4604).
 
-## UTF-8 offsets
-
-rust-analyzer supports clangd's extension for opting into UTF-8 as the coordinate space for offsets (by default, LSP uses UTF-16 offsets).
-
-https://clangd.llvm.org/extensions.html#utf-8-offsets
-
 ## Configuration in `initializationOptions`
 
 **Upstream Issue:** https://github.com/microsoft/language-server-protocol/issues/567
diff --git a/src/tools/rust-analyzer/docs/user/generated_config.adoc b/src/tools/rust-analyzer/docs/user/generated_config.adoc
index acf0aaea859a..36794efe4272 100644
--- a/src/tools/rust-analyzer/docs/user/generated_config.adoc
+++ b/src/tools/rust-analyzer/docs/user/generated_config.adoc
@@ -1,3 +1,9 @@
+[[rust-analyzer.assist.emitMustUse]]rust-analyzer.assist.emitMustUse (default: `false`)::
++
+--
+Whether to insert #[must_use] when generating `as_` methods
+for enum variants.
+--
 [[rust-analyzer.assist.expressionFillDefault]]rust-analyzer.assist.expressionFillDefault (default: `"todo"`)::
 +
 --
@@ -24,6 +30,25 @@ Automatically refresh project info via `cargo metadata` on
 --
 Run build scripts (`build.rs`) for more precise code analysis.
 --
+[[rust-analyzer.cargo.buildScripts.invocationLocation]]rust-analyzer.cargo.buildScripts.invocationLocation (default: `"workspace"`)::
++
+--
+Specifies the working directory for running build scripts.
+- "workspace": run build scripts for a workspace in the workspace's root directory.
+  This is incompatible with `#rust-analyzer.cargo.buildScripts.invocationStrategy#` set to `once`.
+- "root": run build scripts in the project's root directory.
+This config only has an effect when `#rust-analyzer.cargo.buildScripts.overrideCommand#`
+is set.
+--
+[[rust-analyzer.cargo.buildScripts.invocationStrategy]]rust-analyzer.cargo.buildScripts.invocationStrategy (default: `"per_workspace"`)::
++
+--
+Specifies the invocation strategy to use when running the build scripts command.
+If `per_workspace` is set, the command will be executed for each workspace.
+If `once` is set, the command will be executed once.
+This config only has an effect when `#rust-analyzer.cargo.buildScripts.overrideCommand#`
+is set.
+--
 [[rust-analyzer.cargo.buildScripts.overrideCommand]]rust-analyzer.cargo.buildScripts.overrideCommand (default: `null`)::
 +
 --
@@ -118,6 +143,25 @@ List of features to activate. Defaults to
 
 Set to `"all"` to pass `--all-features` to Cargo.
 --
+[[rust-analyzer.checkOnSave.invocationLocation]]rust-analyzer.checkOnSave.invocationLocation (default: `"workspace"`)::
++
+--
+Specifies the working directory for running checks.
+- "workspace": run checks for workspaces in the corresponding workspaces' root directories.
+  This falls back to "root" if `#rust-analyzer.cargo.checkOnSave.invocationStrategy#` is set to `once`.
+- "root": run checks in the project's root directory.
+This config only has an effect when `#rust-analyzer.cargo.buildScripts.overrideCommand#`
+is set.
+--
+[[rust-analyzer.checkOnSave.invocationStrategy]]rust-analyzer.checkOnSave.invocationStrategy (default: `"per_workspace"`)::
++
+--
+Specifies the invocation strategy to use when running the checkOnSave command.
+If `per_workspace` is set, the command will be executed for each workspace.
+If `once` is set, the command will be executed once.
+This config only has an effect when `#rust-analyzer.cargo.buildScripts.overrideCommand#`
+is set.
+--
 [[rust-analyzer.checkOnSave.noDefaultFeatures]]rust-analyzer.checkOnSave.noDefaultFeatures (default: `null`)::
 +
 --
diff --git a/src/tools/rust-analyzer/docs/user/manual.adoc b/src/tools/rust-analyzer/docs/user/manual.adoc
index c30838e5f5e1..49500e390a50 100644
--- a/src/tools/rust-analyzer/docs/user/manual.adoc
+++ b/src/tools/rust-analyzer/docs/user/manual.adoc
@@ -487,6 +487,12 @@ https://docs.helix-editor.com/[Helix] supports LSP by default.
 However, it won't install `rust-analyzer` automatically.
 You can follow instructions for installing <<rust-analyzer-language-server-binary,`rust-analyzer` binary>>.
 
+=== Crates
+
+There is a package named `ra_ap_rust_analyzer` available on https://crates.io/crates/ra_ap_rust-analyzer[crates.io], for someone who wants to use it programmatically.
+
+For more details, see https://github.com/rust-lang/rust-analyzer/blob/master/.github/workflows/publish.yml[the publish workflow].
+
 == Troubleshooting
 
 Start with looking at the rust-analyzer version.
diff --git a/src/tools/rust-analyzer/editors/code/package-lock.json b/src/tools/rust-analyzer/editors/code/package-lock.json
index 3ff4b6897a16..0b25564e28d3 100644
--- a/src/tools/rust-analyzer/editors/code/package-lock.json
+++ b/src/tools/rust-analyzer/editors/code/package-lock.json
@@ -11,7 +11,7 @@
             "dependencies": {
                 "d3": "^7.6.1",
                 "d3-graphviz": "^4.1.1",
-                "vscode-languageclient": "^8.0.0-next.14"
+                "vscode-languageclient": "^8.0.2"
             },
             "devDependencies": {
                 "@types/node": "~16.11.7",
@@ -23,7 +23,7 @@
                 "esbuild": "^0.14.48",
                 "eslint": "^8.19.0",
                 "eslint-config-prettier": "^8.5.0",
-                "ovsx": "^0.5.1",
+                "ovsx": "^0.5.2",
                 "prettier": "^2.7.1",
                 "tslib": "^2.4.0",
                 "typescript": "^4.7.4",
@@ -2874,9 +2874,9 @@
             }
         },
         "node_modules/ovsx": {
-            "version": "0.5.1",
-            "resolved": "https://registry.npmjs.org/ovsx/-/ovsx-0.5.1.tgz",
-            "integrity": "sha512-3OWq0l7DuVHi2bd2aQe5+QVQlFIqvrcw3/2vGXL404L6Tr+R4QHtzfnYYghv8CCa85xJHjU0RhcaC7pyXkAUbg==",
+            "version": "0.5.2",
+            "resolved": "https://registry.npmjs.org/ovsx/-/ovsx-0.5.2.tgz",
+            "integrity": "sha512-UbLultRCk46WddeA0Cly4hoRhzBJUiLgbIEViXlgOvV54LbsppClDkMLoCevUUBHoiNdMX2NuiSgURAEXgCZdw==",
             "dev": true,
             "dependencies": {
                 "commander": "^6.1.0",
@@ -3791,39 +3791,39 @@
             }
         },
         "node_modules/vscode-jsonrpc": {
-            "version": "8.0.0-next.7",
-            "resolved": "https://registry.npmjs.org/vscode-jsonrpc/-/vscode-jsonrpc-8.0.0-next.7.tgz",
-            "integrity": "sha512-JX/F31LEsims0dAlOTKFE4E+AJMiJvdRSRViifFJSqSN7EzeYyWlfuDchF7g91oRNPZOIWfibTkDf3/UMsQGzQ==",
+            "version": "8.0.2",
+            "resolved": "https://registry.npmjs.org/vscode-jsonrpc/-/vscode-jsonrpc-8.0.2.tgz",
+            "integrity": "sha512-RY7HwI/ydoC1Wwg4gJ3y6LpU9FJRZAUnTYMXthqhFXXu77ErDd/xkREpGuk4MyYkk4a+XDWAMqe0S3KkelYQEQ==",
             "engines": {
                 "node": ">=14.0.0"
             }
         },
         "node_modules/vscode-languageclient": {
-            "version": "8.0.0-next.14",
-            "resolved": "https://registry.npmjs.org/vscode-languageclient/-/vscode-languageclient-8.0.0-next.14.tgz",
-            "integrity": "sha512-NqjkOuDTMu8uo+PhoMsV72VO9Gd3wBi/ZpOrkRUOrWKQo7yUdiIw183g8wjH8BImgbK9ZP51HM7TI0ZhCnI1Mw==",
+            "version": "8.0.2",
+            "resolved": "https://registry.npmjs.org/vscode-languageclient/-/vscode-languageclient-8.0.2.tgz",
+            "integrity": "sha512-lHlthJtphG9gibGb/y72CKqQUxwPsMXijJVpHEC2bvbFqxmkj9LwQ3aGU9dwjBLqsX1S4KjShYppLvg1UJDF/Q==",
             "dependencies": {
                 "minimatch": "^3.0.4",
                 "semver": "^7.3.5",
-                "vscode-languageserver-protocol": "3.17.0-next.16"
+                "vscode-languageserver-protocol": "3.17.2"
             },
             "engines": {
-                "vscode": "^1.66.0"
+                "vscode": "^1.67.0"
             }
         },
         "node_modules/vscode-languageserver-protocol": {
-            "version": "3.17.0-next.16",
-            "resolved": "https://registry.npmjs.org/vscode-languageserver-protocol/-/vscode-languageserver-protocol-3.17.0-next.16.tgz",
-            "integrity": "sha512-tx4DnXw9u3N7vw+bx6n2NKp6FoxoNwiP/biH83AS30I2AnTGyLd7afSeH6Oewn2E8jvB7K15bs12sMppkKOVeQ==",
+            "version": "3.17.2",
+            "resolved": "https://registry.npmjs.org/vscode-languageserver-protocol/-/vscode-languageserver-protocol-3.17.2.tgz",
+            "integrity": "sha512-8kYisQ3z/SQ2kyjlNeQxbkkTNmVFoQCqkmGrzLH6A9ecPlgTbp3wDTnUNqaUxYr4vlAcloxx8zwy7G5WdguYNg==",
             "dependencies": {
-                "vscode-jsonrpc": "8.0.0-next.7",
-                "vscode-languageserver-types": "3.17.0-next.9"
+                "vscode-jsonrpc": "8.0.2",
+                "vscode-languageserver-types": "3.17.2"
             }
         },
         "node_modules/vscode-languageserver-types": {
-            "version": "3.17.0-next.9",
-            "resolved": "https://registry.npmjs.org/vscode-languageserver-types/-/vscode-languageserver-types-3.17.0-next.9.tgz",
-            "integrity": "sha512-9/PeDNPYduaoXRUzYpqmu4ZV9L01HGo0wH9FUt+sSHR7IXwA7xoXBfNUlv8gB9H0D2WwEmMomSy1NmhjKQyn3A=="
+            "version": "3.17.2",
+            "resolved": "https://registry.npmjs.org/vscode-languageserver-types/-/vscode-languageserver-types-3.17.2.tgz",
+            "integrity": "sha512-zHhCWatviizPIq9B7Vh9uvrH6x3sK8itC84HkamnBWoDFJtzBf7SWlpLCZUit72b3os45h6RWQNC9xHRDF8dRA=="
         },
         "node_modules/which": {
             "version": "2.0.2",
@@ -5958,9 +5958,9 @@
             }
         },
         "ovsx": {
-            "version": "0.5.1",
-            "resolved": "https://registry.npmjs.org/ovsx/-/ovsx-0.5.1.tgz",
-            "integrity": "sha512-3OWq0l7DuVHi2bd2aQe5+QVQlFIqvrcw3/2vGXL404L6Tr+R4QHtzfnYYghv8CCa85xJHjU0RhcaC7pyXkAUbg==",
+            "version": "0.5.2",
+            "resolved": "https://registry.npmjs.org/ovsx/-/ovsx-0.5.2.tgz",
+            "integrity": "sha512-UbLultRCk46WddeA0Cly4hoRhzBJUiLgbIEViXlgOvV54LbsppClDkMLoCevUUBHoiNdMX2NuiSgURAEXgCZdw==",
             "dev": true,
             "requires": {
                 "commander": "^6.1.0",
@@ -6634,33 +6634,33 @@
             }
         },
         "vscode-jsonrpc": {
-            "version": "8.0.0-next.7",
-            "resolved": "https://registry.npmjs.org/vscode-jsonrpc/-/vscode-jsonrpc-8.0.0-next.7.tgz",
-            "integrity": "sha512-JX/F31LEsims0dAlOTKFE4E+AJMiJvdRSRViifFJSqSN7EzeYyWlfuDchF7g91oRNPZOIWfibTkDf3/UMsQGzQ=="
+            "version": "8.0.2",
+            "resolved": "https://registry.npmjs.org/vscode-jsonrpc/-/vscode-jsonrpc-8.0.2.tgz",
+            "integrity": "sha512-RY7HwI/ydoC1Wwg4gJ3y6LpU9FJRZAUnTYMXthqhFXXu77ErDd/xkREpGuk4MyYkk4a+XDWAMqe0S3KkelYQEQ=="
         },
         "vscode-languageclient": {
-            "version": "8.0.0-next.14",
-            "resolved": "https://registry.npmjs.org/vscode-languageclient/-/vscode-languageclient-8.0.0-next.14.tgz",
-            "integrity": "sha512-NqjkOuDTMu8uo+PhoMsV72VO9Gd3wBi/ZpOrkRUOrWKQo7yUdiIw183g8wjH8BImgbK9ZP51HM7TI0ZhCnI1Mw==",
+            "version": "8.0.2",
+            "resolved": "https://registry.npmjs.org/vscode-languageclient/-/vscode-languageclient-8.0.2.tgz",
+            "integrity": "sha512-lHlthJtphG9gibGb/y72CKqQUxwPsMXijJVpHEC2bvbFqxmkj9LwQ3aGU9dwjBLqsX1S4KjShYppLvg1UJDF/Q==",
             "requires": {
                 "minimatch": "^3.0.4",
                 "semver": "^7.3.5",
-                "vscode-languageserver-protocol": "3.17.0-next.16"
+                "vscode-languageserver-protocol": "3.17.2"
             }
         },
         "vscode-languageserver-protocol": {
-            "version": "3.17.0-next.16",
-            "resolved": "https://registry.npmjs.org/vscode-languageserver-protocol/-/vscode-languageserver-protocol-3.17.0-next.16.tgz",
-            "integrity": "sha512-tx4DnXw9u3N7vw+bx6n2NKp6FoxoNwiP/biH83AS30I2AnTGyLd7afSeH6Oewn2E8jvB7K15bs12sMppkKOVeQ==",
+            "version": "3.17.2",
+            "resolved": "https://registry.npmjs.org/vscode-languageserver-protocol/-/vscode-languageserver-protocol-3.17.2.tgz",
+            "integrity": "sha512-8kYisQ3z/SQ2kyjlNeQxbkkTNmVFoQCqkmGrzLH6A9ecPlgTbp3wDTnUNqaUxYr4vlAcloxx8zwy7G5WdguYNg==",
             "requires": {
-                "vscode-jsonrpc": "8.0.0-next.7",
-                "vscode-languageserver-types": "3.17.0-next.9"
+                "vscode-jsonrpc": "8.0.2",
+                "vscode-languageserver-types": "3.17.2"
             }
         },
         "vscode-languageserver-types": {
-            "version": "3.17.0-next.9",
-            "resolved": "https://registry.npmjs.org/vscode-languageserver-types/-/vscode-languageserver-types-3.17.0-next.9.tgz",
-            "integrity": "sha512-9/PeDNPYduaoXRUzYpqmu4ZV9L01HGo0wH9FUt+sSHR7IXwA7xoXBfNUlv8gB9H0D2WwEmMomSy1NmhjKQyn3A=="
+            "version": "3.17.2",
+            "resolved": "https://registry.npmjs.org/vscode-languageserver-types/-/vscode-languageserver-types-3.17.2.tgz",
+            "integrity": "sha512-zHhCWatviizPIq9B7Vh9uvrH6x3sK8itC84HkamnBWoDFJtzBf7SWlpLCZUit72b3os45h6RWQNC9xHRDF8dRA=="
         },
         "which": {
             "version": "2.0.2",
diff --git a/src/tools/rust-analyzer/editors/code/package.json b/src/tools/rust-analyzer/editors/code/package.json
index f1dd3aa79ff0..1a97a9c08937 100644
--- a/src/tools/rust-analyzer/editors/code/package.json
+++ b/src/tools/rust-analyzer/editors/code/package.json
@@ -37,7 +37,7 @@
     "dependencies": {
         "d3": "^7.6.1",
         "d3-graphviz": "^4.1.1",
-        "vscode-languageclient": "^8.0.0-next.14"
+        "vscode-languageclient": "^8.0.2"
     },
     "devDependencies": {
         "@types/node": "~16.11.7",
@@ -49,7 +49,7 @@
         "esbuild": "^0.14.48",
         "eslint": "^8.19.0",
         "eslint-config-prettier": "^8.5.0",
-        "ovsx": "^0.5.1",
+        "ovsx": "^0.5.2",
         "prettier": "^2.7.1",
         "tslib": "^2.4.0",
         "typescript": "^4.7.4",
@@ -60,6 +60,7 @@
         "onCommand:rust-analyzer.analyzerStatus",
         "onCommand:rust-analyzer.memoryUsage",
         "onCommand:rust-analyzer.reloadWorkspace",
+        "onCommand:rust-analyzer.startServer",
         "workspaceContains:*/Cargo.toml",
         "workspaceContains:*/rust-project.json"
     ],
@@ -99,22 +100,32 @@
             {
                 "command": "rust-analyzer.syntaxTree",
                 "title": "Show Syntax Tree",
-                "category": "rust-analyzer"
+                "category": "rust-analyzer (debug command)"
             },
             {
                 "command": "rust-analyzer.viewHir",
                 "title": "View Hir",
-                "category": "rust-analyzer"
+                "category": "rust-analyzer (debug command)"
             },
             {
                 "command": "rust-analyzer.viewFileText",
                 "title": "View File Text (as seen by the server)",
-                "category": "rust-analyzer"
+                "category": "rust-analyzer (debug command)"
             },
             {
                 "command": "rust-analyzer.viewItemTree",
                 "title": "Debug ItemTree",
-                "category": "rust-analyzer"
+                "category": "rust-analyzer (debug command)"
+            },
+            {
+                "command": "rust-analyzer.shuffleCrateGraph",
+                "title": "Shuffle Crate Graph",
+                "category": "rust-analyzer (debug command)"
+            },
+            {
+                "command": "rust-analyzer.memoryUsage",
+                "title": "Memory Usage (Clears Database)",
+                "category": "rust-analyzer (debug command)"
             },
             {
                 "command": "rust-analyzer.viewCrateGraph",
@@ -171,16 +182,6 @@
                 "title": "Status",
                 "category": "rust-analyzer"
             },
-            {
-                "command": "rust-analyzer.memoryUsage",
-                "title": "Memory Usage (Clears Database)",
-                "category": "rust-analyzer"
-            },
-            {
-                "command": "rust-analyzer.shuffleCrateGraph",
-                "title": "Shuffle Crate Graph",
-                "category": "rust-analyzer"
-            },
             {
                 "command": "rust-analyzer.reloadWorkspace",
                 "title": "Reload workspace",
@@ -191,6 +192,16 @@
                 "title": "Restart server",
                 "category": "rust-analyzer"
             },
+            {
+                "command": "rust-analyzer.startServer",
+                "title": "Start server",
+                "category": "rust-analyzer"
+            },
+            {
+                "command": "rust-analyzer.stopServer",
+                "title": "Stop server",
+                "category": "rust-analyzer"
+            },
             {
                 "command": "rust-analyzer.onEnter",
                 "title": "Enhanced enter key",
@@ -386,6 +397,11 @@
                     "type": "boolean"
                 },
                 "$generated-start": {},
+                "rust-analyzer.assist.emitMustUse": {
+                    "markdownDescription": "Whether to insert #[must_use] when generating `as_` methods\nfor enum variants.",
+                    "default": false,
+                    "type": "boolean"
+                },
                 "rust-analyzer.assist.expressionFillDefault": {
                     "markdownDescription": "Placeholder expression to use for missing expressions in assists.",
                     "default": "todo",
@@ -421,6 +437,32 @@
                     "default": true,
                     "type": "boolean"
                 },
+                "rust-analyzer.cargo.buildScripts.invocationLocation": {
+                    "markdownDescription": "Specifies the working directory for running build scripts.\n- \"workspace\": run build scripts for a workspace in the workspace's root directory.\n    This is incompatible with `#rust-analyzer.cargo.buildScripts.invocationStrategy#` set to `once`.\n- \"root\": run build scripts in the project's root directory.\nThis config only has an effect when `#rust-analyzer.cargo.buildScripts.overrideCommand#`\nis set.",
+                    "default": "workspace",
+                    "type": "string",
+                    "enum": [
+                        "workspace",
+                        "root"
+                    ],
+                    "enumDescriptions": [
+                        "The command will be executed in the corresponding workspace root.",
+                        "The command will be executed in the project root."
+                    ]
+                },
+                "rust-analyzer.cargo.buildScripts.invocationStrategy": {
+                    "markdownDescription": "Specifies the invocation strategy to use when running the build scripts command.\nIf `per_workspace` is set, the command will be executed for each workspace.\nIf `once` is set, the command will be executed once.\nThis config only has an effect when `#rust-analyzer.cargo.buildScripts.overrideCommand#`\nis set.",
+                    "default": "per_workspace",
+                    "type": "string",
+                    "enum": [
+                        "per_workspace",
+                        "once"
+                    ],
+                    "enumDescriptions": [
+                        "The command will be executed for each workspace.",
+                        "The command will be executed once."
+                    ]
+                },
                 "rust-analyzer.cargo.buildScripts.overrideCommand": {
                     "markdownDescription": "Override the command rust-analyzer uses to run build scripts and\nbuild procedural macros. The command is required to output json\nand should therefore include `--message-format=json` or a similar\noption.\n\nBy default, a cargo invocation will be constructed for the configured\ntargets and features, with the following base command line:\n\n```bash\ncargo check --quiet --workspace --message-format=json --all-targets\n```\n.",
                     "default": null,
@@ -546,6 +588,32 @@
                         }
                     ]
                 },
+                "rust-analyzer.checkOnSave.invocationLocation": {
+                    "markdownDescription": "Specifies the working directory for running checks.\n- \"workspace\": run checks for workspaces in the corresponding workspaces' root directories.\n    This falls back to \"root\" if `#rust-analyzer.cargo.checkOnSave.invocationStrategy#` is set to `once`.\n- \"root\": run checks in the project's root directory.\nThis config only has an effect when `#rust-analyzer.cargo.buildScripts.overrideCommand#`\nis set.",
+                    "default": "workspace",
+                    "type": "string",
+                    "enum": [
+                        "workspace",
+                        "root"
+                    ],
+                    "enumDescriptions": [
+                        "The command will be executed in the corresponding workspace root.",
+                        "The command will be executed in the project root."
+                    ]
+                },
+                "rust-analyzer.checkOnSave.invocationStrategy": {
+                    "markdownDescription": "Specifies the invocation strategy to use when running the checkOnSave command.\nIf `per_workspace` is set, the command will be executed for each workspace.\nIf `once` is set, the command will be executed once.\nThis config only has an effect when `#rust-analyzer.cargo.buildScripts.overrideCommand#`\nis set.",
+                    "default": "per_workspace",
+                    "type": "string",
+                    "enum": [
+                        "per_workspace",
+                        "once"
+                    ],
+                    "enumDescriptions": [
+                        "The command will be executed for each workspace.",
+                        "The command will be executed once."
+                    ]
+                },
                 "rust-analyzer.checkOnSave.noDefaultFeatures": {
                     "markdownDescription": "Whether to pass `--no-default-features` to Cargo. Defaults to\n`#rust-analyzer.cargo.noDefaultFeatures#`.",
                     "default": null,
diff --git a/src/tools/rust-analyzer/editors/code/src/ast_inspector.ts b/src/tools/rust-analyzer/editors/code/src/ast_inspector.ts
index e57fb20e2cf8..176040120f41 100644
--- a/src/tools/rust-analyzer/editors/code/src/ast_inspector.ts
+++ b/src/tools/rust-analyzer/editors/code/src/ast_inspector.ts
@@ -35,8 +35,10 @@ export class AstInspector implements vscode.HoverProvider, vscode.DefinitionProv
     });
 
     constructor(ctx: Ctx) {
-        ctx.pushCleanup(vscode.languages.registerHoverProvider({ scheme: "rust-analyzer" }, this));
-        ctx.pushCleanup(vscode.languages.registerDefinitionProvider({ language: "rust" }, this));
+        ctx.pushExtCleanup(
+            vscode.languages.registerHoverProvider({ scheme: "rust-analyzer" }, this)
+        );
+        ctx.pushExtCleanup(vscode.languages.registerDefinitionProvider({ language: "rust" }, this));
         vscode.workspace.onDidCloseTextDocument(
             this.onDidCloseTextDocument,
             this,
@@ -52,8 +54,6 @@ export class AstInspector implements vscode.HoverProvider, vscode.DefinitionProv
             this,
             ctx.subscriptions
         );
-
-        ctx.pushCleanup(this);
     }
     dispose() {
         this.setRustEditor(undefined);
diff --git a/src/tools/rust-analyzer/editors/code/src/bootstrap.ts b/src/tools/rust-analyzer/editors/code/src/bootstrap.ts
new file mode 100644
index 000000000000..374c3b8144c3
--- /dev/null
+++ b/src/tools/rust-analyzer/editors/code/src/bootstrap.ts
@@ -0,0 +1,148 @@
+import * as vscode from "vscode";
+import * as os from "os";
+import { Config } from "./config";
+import { log, isValidExecutable } from "./util";
+import { PersistentState } from "./persistent_state";
+import { exec } from "child_process";
+
+export async function bootstrap(
+    context: vscode.ExtensionContext,
+    config: Config,
+    state: PersistentState
+): Promise<string> {
+    const path = await getServer(context, config, state);
+    if (!path) {
+        throw new Error(
+            "Rust Analyzer Language Server is not available. " +
+                "Please, ensure its [proper installation](https://rust-analyzer.github.io/manual.html#installation)."
+        );
+    }
+
+    log.info("Using server binary at", path);
+
+    if (!isValidExecutable(path)) {
+        if (config.serverPath) {
+            throw new Error(`Failed to execute ${path} --version. \`config.server.path\` or \`config.serverPath\` has been set explicitly.\
+            Consider removing this config or making a valid server binary available at that path.`);
+        } else {
+            throw new Error(`Failed to execute ${path} --version`);
+        }
+    }
+
+    return path;
+}
+
+async function patchelf(dest: vscode.Uri): Promise<void> {
+    await vscode.window.withProgress(
+        {
+            location: vscode.ProgressLocation.Notification,
+            title: "Patching rust-analyzer for NixOS",
+        },
+        async (progress, _) => {
+            const expression = `
+            {srcStr, pkgs ? import <nixpkgs> {}}:
+                pkgs.stdenv.mkDerivation {
+                    name = "rust-analyzer";
+                    src = /. + srcStr;
+                    phases = [ "installPhase" "fixupPhase" ];
+                    installPhase = "cp $src $out";
+                    fixupPhase = ''
+                    chmod 755 $out
+                    patchelf --set-interpreter "$(cat $NIX_CC/nix-support/dynamic-linker)" $out
+                    '';
+                }
+            `;
+            const origFile = vscode.Uri.file(dest.fsPath + "-orig");
+            await vscode.workspace.fs.rename(dest, origFile, { overwrite: true });
+            try {
+                progress.report({ message: "Patching executable", increment: 20 });
+                await new Promise((resolve, reject) => {
+                    const handle = exec(
+                        `nix-build -E - --argstr srcStr '${origFile.fsPath}' -o '${dest.fsPath}'`,
+                        (err, stdout, stderr) => {
+                            if (err != null) {
+                                reject(Error(stderr));
+                            } else {
+                                resolve(stdout);
+                            }
+                        }
+                    );
+                    handle.stdin?.write(expression);
+                    handle.stdin?.end();
+                });
+            } finally {
+                await vscode.workspace.fs.delete(origFile);
+            }
+        }
+    );
+}
+
+async function getServer(
+    context: vscode.ExtensionContext,
+    config: Config,
+    state: PersistentState
+): Promise<string | undefined> {
+    const explicitPath = serverPath(config);
+    if (explicitPath) {
+        if (explicitPath.startsWith("~/")) {
+            return os.homedir() + explicitPath.slice("~".length);
+        }
+        return explicitPath;
+    }
+    if (config.package.releaseTag === null) return "rust-analyzer";
+
+    const ext = process.platform === "win32" ? ".exe" : "";
+    const bundled = vscode.Uri.joinPath(context.extensionUri, "server", `rust-analyzer${ext}`);
+    const bundledExists = await vscode.workspace.fs.stat(bundled).then(
+        () => true,
+        () => false
+    );
+    if (bundledExists) {
+        let server = bundled;
+        if (await isNixOs()) {
+            await vscode.workspace.fs.createDirectory(config.globalStorageUri).then();
+            const dest = vscode.Uri.joinPath(config.globalStorageUri, `rust-analyzer${ext}`);
+            let exists = await vscode.workspace.fs.stat(dest).then(
+                () => true,
+                () => false
+            );
+            if (exists && config.package.version !== state.serverVersion) {
+                await vscode.workspace.fs.delete(dest);
+                exists = false;
+            }
+            if (!exists) {
+                await vscode.workspace.fs.copy(bundled, dest);
+                await patchelf(dest);
+            }
+            server = dest;
+        }
+        await state.updateServerVersion(config.package.version);
+        return server.fsPath;
+    }
+
+    await state.updateServerVersion(undefined);
+    await vscode.window.showErrorMessage(
+        "Unfortunately we don't ship binaries for your platform yet. " +
+            "You need to manually clone the rust-analyzer repository and " +
+            "run `cargo xtask install --server` to build the language server from sources. " +
+            "If you feel that your platform should be supported, please create an issue " +
+            "about that [here](https://github.com/rust-lang/rust-analyzer/issues) and we " +
+            "will consider it."
+    );
+    return undefined;
+}
+function serverPath(config: Config): string | null {
+    return process.env.__RA_LSP_SERVER_DEBUG ?? config.serverPath;
+}
+
+async function isNixOs(): Promise<boolean> {
+    try {
+        const contents = (
+            await vscode.workspace.fs.readFile(vscode.Uri.file("/etc/os-release"))
+        ).toString();
+        const idString = contents.split("\n").find((a) => a.startsWith("ID=")) || "ID=linux";
+        return idString.indexOf("nixos") !== -1;
+    } catch {
+        return false;
+    }
+}
diff --git a/src/tools/rust-analyzer/editors/code/src/client.ts b/src/tools/rust-analyzer/editors/code/src/client.ts
index 05d4d08f70b6..fb667619c86b 100644
--- a/src/tools/rust-analyzer/editors/code/src/client.ts
+++ b/src/tools/rust-analyzer/editors/code/src/client.ts
@@ -4,9 +4,7 @@ import * as ra from "../src/lsp_ext";
 import * as Is from "vscode-languageclient/lib/common/utils/is";
 import { assert } from "./util";
 import { WorkspaceEdit } from "vscode";
-import { Workspace } from "./ctx";
-import { substituteVariablesInEnv } from "./config";
-import { outputChannel, traceOutputChannel } from "./main";
+import { substituteVSCodeVariables } from "./config";
 import { randomUUID } from "crypto";
 
 export interface Env {
@@ -65,40 +63,42 @@ function renderHoverActions(actions: ra.CommandLinkGroup[]): vscode.MarkdownStri
 }
 
 export async function createClient(
-    serverPath: string,
-    workspace: Workspace,
-    extraEnv: Env
+    traceOutputChannel: vscode.OutputChannel,
+    outputChannel: vscode.OutputChannel,
+    initializationOptions: vscode.WorkspaceConfiguration,
+    serverOptions: lc.ServerOptions
 ): Promise<lc.LanguageClient> {
-    // '.' Is the fallback if no folder is open
-    // TODO?: Workspace folders support Uri's (eg: file://test.txt).
-    // It might be a good idea to test if the uri points to a file.
-
-    const newEnv = substituteVariablesInEnv(Object.assign({}, process.env, extraEnv));
-    const run: lc.Executable = {
-        command: serverPath,
-        options: { env: newEnv },
-    };
-    const serverOptions: lc.ServerOptions = {
-        run,
-        debug: run,
-    };
-
-    let initializationOptions = vscode.workspace.getConfiguration("rust-analyzer");
-
-    if (workspace.kind === "Detached Files") {
-        initializationOptions = {
-            detachedFiles: workspace.files.map((file) => file.uri.fsPath),
-            ...initializationOptions,
-        };
-    }
-
     const clientOptions: lc.LanguageClientOptions = {
         documentSelector: [{ scheme: "file", language: "rust" }],
         initializationOptions,
         diagnosticCollectionName: "rustc",
-        traceOutputChannel: traceOutputChannel(),
-        outputChannel: outputChannel(),
+        traceOutputChannel,
+        outputChannel,
         middleware: {
+            workspace: {
+                // HACK: This is a workaround, when the client has been disposed, VSCode
+                // continues to emit events to the client and the default one for this event
+                // attempt to restart the client for no reason
+                async didChangeWatchedFile(event, next) {
+                    if (client.isRunning()) {
+                        await next(event);
+                    }
+                },
+                async configuration(
+                    params: lc.ConfigurationParams,
+                    token: vscode.CancellationToken,
+                    next: lc.ConfigurationRequest.HandlerSignature
+                ) {
+                    const resp = await next(params, token);
+                    if (resp && Array.isArray(resp)) {
+                        return resp.map((val) => {
+                            return substituteVSCodeVariables(val);
+                        });
+                    } else {
+                        return resp;
+                    }
+                },
+            },
             async provideHover(
                 document: vscode.TextDocument,
                 position: vscode.Position,
@@ -255,6 +255,9 @@ export async function createClient(
 }
 
 class ExperimentalFeatures implements lc.StaticFeature {
+    getState(): lc.FeatureState {
+        return { kind: "static" };
+    }
     fillClientCapabilities(capabilities: lc.ClientCapabilities): void {
         const caps: any = capabilities.experimental ?? {};
         caps.snippetTextEdit = true;
diff --git a/src/tools/rust-analyzer/editors/code/src/commands.ts b/src/tools/rust-analyzer/editors/code/src/commands.ts
index b9ad525e361f..312087e4cffe 100644
--- a/src/tools/rust-analyzer/editors/code/src/commands.ts
+++ b/src/tools/rust-analyzer/editors/code/src/commands.ts
@@ -3,7 +3,7 @@ import * as lc from "vscode-languageclient";
 import * as ra from "./lsp_ext";
 import * as path from "path";
 
-import { Ctx, Cmd } from "./ctx";
+import { Ctx, Cmd, CtxInit } from "./ctx";
 import { applySnippetWorkspaceEdit, applySnippetTextEdits } from "./snippets";
 import { spawnSync } from "child_process";
 import { RunnableQuickPick, selectRunnable, createTask, createArgs } from "./run";
@@ -16,21 +16,21 @@ import { LINKED_COMMANDS } from "./client";
 export * from "./ast_inspector";
 export * from "./run";
 
-export function analyzerStatus(ctx: Ctx): Cmd {
+export function analyzerStatus(ctx: CtxInit): Cmd {
     const tdcp = new (class implements vscode.TextDocumentContentProvider {
         readonly uri = vscode.Uri.parse("rust-analyzer-status://status");
         readonly eventEmitter = new vscode.EventEmitter<vscode.Uri>();
 
-        provideTextDocumentContent(_uri: vscode.Uri): vscode.ProviderResult<string> {
+        async provideTextDocumentContent(_uri: vscode.Uri): Promise<string> {
             if (!vscode.window.activeTextEditor) return "";
+            const client = ctx.client;
 
             const params: ra.AnalyzerStatusParams = {};
             const doc = ctx.activeRustEditor?.document;
             if (doc != null) {
-                params.textDocument =
-                    ctx.client.code2ProtocolConverter.asTextDocumentIdentifier(doc);
+                params.textDocument = client.code2ProtocolConverter.asTextDocumentIdentifier(doc);
             }
-            return ctx.client.sendRequest(ra.analyzerStatus, params);
+            return await client.sendRequest(ra.analyzerStatus, params);
         }
 
         get onDidChange(): vscode.Event<vscode.Uri> {
@@ -38,7 +38,7 @@ export function analyzerStatus(ctx: Ctx): Cmd {
         }
     })();
 
-    ctx.pushCleanup(
+    ctx.pushExtCleanup(
         vscode.workspace.registerTextDocumentContentProvider("rust-analyzer-status", tdcp)
     );
 
@@ -52,7 +52,7 @@ export function analyzerStatus(ctx: Ctx): Cmd {
     };
 }
 
-export function memoryUsage(ctx: Ctx): Cmd {
+export function memoryUsage(ctx: CtxInit): Cmd {
     const tdcp = new (class implements vscode.TextDocumentContentProvider {
         readonly uri = vscode.Uri.parse("rust-analyzer-memory://memory");
         readonly eventEmitter = new vscode.EventEmitter<vscode.Uri>();
@@ -70,7 +70,7 @@ export function memoryUsage(ctx: Ctx): Cmd {
         }
     })();
 
-    ctx.pushCleanup(
+    ctx.pushExtCleanup(
         vscode.workspace.registerTextDocumentContentProvider("rust-analyzer-memory", tdcp)
     );
 
@@ -81,25 +81,21 @@ export function memoryUsage(ctx: Ctx): Cmd {
     };
 }
 
-export function shuffleCrateGraph(ctx: Ctx): Cmd {
+export function shuffleCrateGraph(ctx: CtxInit): Cmd {
     return async () => {
-        const client = ctx.client;
-        if (!client) return;
-
-        await client.sendRequest(ra.shuffleCrateGraph);
+        return ctx.client.sendRequest(ra.shuffleCrateGraph);
     };
 }
 
-export function matchingBrace(ctx: Ctx): Cmd {
+export function matchingBrace(ctx: CtxInit): Cmd {
     return async () => {
         const editor = ctx.activeRustEditor;
+        if (!editor) return;
+
         const client = ctx.client;
-        if (!editor || !client) return;
 
         const response = await client.sendRequest(ra.matchingBrace, {
-            textDocument: ctx.client.code2ProtocolConverter.asTextDocumentIdentifier(
-                editor.document
-            ),
+            textDocument: client.code2ProtocolConverter.asTextDocumentIdentifier(editor.document),
             positions: editor.selections.map((s) =>
                 client.code2ProtocolConverter.asPosition(s.active)
             ),
@@ -113,17 +109,16 @@ export function matchingBrace(ctx: Ctx): Cmd {
     };
 }
 
-export function joinLines(ctx: Ctx): Cmd {
+export function joinLines(ctx: CtxInit): Cmd {
     return async () => {
         const editor = ctx.activeRustEditor;
+        if (!editor) return;
+
         const client = ctx.client;
-        if (!editor || !client) return;
 
         const items: lc.TextEdit[] = await client.sendRequest(ra.joinLines, {
             ranges: editor.selections.map((it) => client.code2ProtocolConverter.asRange(it)),
-            textDocument: ctx.client.code2ProtocolConverter.asTextDocumentIdentifier(
-                editor.document
-            ),
+            textDocument: client.code2ProtocolConverter.asTextDocumentIdentifier(editor.document),
         });
         const textEdits = await client.protocol2CodeConverter.asTextEdits(items);
         await editor.edit((builder) => {
@@ -134,25 +129,23 @@ export function joinLines(ctx: Ctx): Cmd {
     };
 }
 
-export function moveItemUp(ctx: Ctx): Cmd {
+export function moveItemUp(ctx: CtxInit): Cmd {
     return moveItem(ctx, ra.Direction.Up);
 }
 
-export function moveItemDown(ctx: Ctx): Cmd {
+export function moveItemDown(ctx: CtxInit): Cmd {
     return moveItem(ctx, ra.Direction.Down);
 }
 
-export function moveItem(ctx: Ctx, direction: ra.Direction): Cmd {
+export function moveItem(ctx: CtxInit, direction: ra.Direction): Cmd {
     return async () => {
         const editor = ctx.activeRustEditor;
+        if (!editor) return;
         const client = ctx.client;
-        if (!editor || !client) return;
 
         const lcEdits = await client.sendRequest(ra.moveItem, {
             range: client.code2ProtocolConverter.asRange(editor.selection),
-            textDocument: ctx.client.code2ProtocolConverter.asTextDocumentIdentifier(
-                editor.document
-            ),
+            textDocument: client.code2ProtocolConverter.asTextDocumentIdentifier(editor.document),
             direction,
         });
 
@@ -163,16 +156,16 @@ export function moveItem(ctx: Ctx, direction: ra.Direction): Cmd {
     };
 }
 
-export function onEnter(ctx: Ctx): Cmd {
+export function onEnter(ctx: CtxInit): Cmd {
     async function handleKeypress() {
         const editor = ctx.activeRustEditor;
+
+        if (!editor) return false;
+
         const client = ctx.client;
-
-        if (!editor || !client) return false;
-
         const lcEdits = await client
             .sendRequest(ra.onEnter, {
-                textDocument: ctx.client.code2ProtocolConverter.asTextDocumentIdentifier(
+                textDocument: client.code2ProtocolConverter.asTextDocumentIdentifier(
                     editor.document
                 ),
                 position: client.code2ProtocolConverter.asPosition(editor.selection.active),
@@ -195,17 +188,16 @@ export function onEnter(ctx: Ctx): Cmd {
     };
 }
 
-export function parentModule(ctx: Ctx): Cmd {
+export function parentModule(ctx: CtxInit): Cmd {
     return async () => {
         const editor = vscode.window.activeTextEditor;
-        const client = ctx.client;
-        if (!editor || !client) return;
+        if (!editor) return;
         if (!(isRustDocument(editor.document) || isCargoTomlDocument(editor.document))) return;
 
+        const client = ctx.client;
+
         const locations = await client.sendRequest(ra.parentModule, {
-            textDocument: ctx.client.code2ProtocolConverter.asTextDocumentIdentifier(
-                editor.document
-            ),
+            textDocument: client.code2ProtocolConverter.asTextDocumentIdentifier(editor.document),
             position: client.code2ProtocolConverter.asPosition(editor.selection.active),
         });
         if (!locations) return;
@@ -233,16 +225,14 @@ export function parentModule(ctx: Ctx): Cmd {
     };
 }
 
-export function openCargoToml(ctx: Ctx): Cmd {
+export function openCargoToml(ctx: CtxInit): Cmd {
     return async () => {
         const editor = ctx.activeRustEditor;
-        const client = ctx.client;
-        if (!editor || !client) return;
+        if (!editor) return;
 
+        const client = ctx.client;
         const response = await client.sendRequest(ra.openCargoToml, {
-            textDocument: ctx.client.code2ProtocolConverter.asTextDocumentIdentifier(
-                editor.document
-            ),
+            textDocument: client.code2ProtocolConverter.asTextDocumentIdentifier(editor.document),
         });
         if (!response) return;
 
@@ -256,15 +246,16 @@ export function openCargoToml(ctx: Ctx): Cmd {
     };
 }
 
-export function ssr(ctx: Ctx): Cmd {
+export function ssr(ctx: CtxInit): Cmd {
     return async () => {
         const editor = vscode.window.activeTextEditor;
+        if (!editor) return;
+
         const client = ctx.client;
-        if (!editor || !client) return;
 
         const position = editor.selection.active;
         const selections = editor.selections;
-        const textDocument = ctx.client.code2ProtocolConverter.asTextDocumentIdentifier(
+        const textDocument = client.code2ProtocolConverter.asTextDocumentIdentifier(
             editor.document
         );
 
@@ -312,8 +303,12 @@ export function ssr(ctx: Ctx): Cmd {
     };
 }
 
-export function serverVersion(ctx: Ctx): Cmd {
+export function serverVersion(ctx: CtxInit): Cmd {
     return async () => {
+        if (!ctx.serverPath) {
+            void vscode.window.showWarningMessage(`rust-analyzer server is not running`);
+            return;
+        }
         const { stdout } = spawnSync(ctx.serverPath, ["--version"], { encoding: "utf8" });
         const versionString = stdout.slice(`rust-analyzer `.length).trim();
 
@@ -324,7 +319,7 @@ export function serverVersion(ctx: Ctx): Cmd {
 // Opens the virtual file that will show the syntax tree
 //
 // The contents of the file come from the `TextDocumentContentProvider`
-export function syntaxTree(ctx: Ctx): Cmd {
+export function syntaxTree(ctx: CtxInit): Cmd {
     const tdcp = new (class implements vscode.TextDocumentContentProvider {
         readonly uri = vscode.Uri.parse("rust-analyzer-syntax-tree://syntaxtree/tree.rast");
         readonly eventEmitter = new vscode.EventEmitter<vscode.Uri>();
@@ -354,21 +349,22 @@ export function syntaxTree(ctx: Ctx): Cmd {
             }
         }
 
-        provideTextDocumentContent(
+        async provideTextDocumentContent(
             uri: vscode.Uri,
             ct: vscode.CancellationToken
-        ): vscode.ProviderResult<string> {
+        ): Promise<string> {
             const rustEditor = ctx.activeRustEditor;
             if (!rustEditor) return "";
+            const client = ctx.client;
 
             // When the range based query is enabled we take the range of the selection
             const range =
                 uri.query === "range=true" && !rustEditor.selection.isEmpty
-                    ? ctx.client.code2ProtocolConverter.asRange(rustEditor.selection)
+                    ? client.code2ProtocolConverter.asRange(rustEditor.selection)
                     : null;
 
             const params = { textDocument: { uri: rustEditor.document.uri.toString() }, range };
-            return ctx.client.sendRequest(ra.syntaxTree, params, ct);
+            return client.sendRequest(ra.syntaxTree, params, ct);
         }
 
         get onDidChange(): vscode.Event<vscode.Uri> {
@@ -376,12 +372,11 @@ export function syntaxTree(ctx: Ctx): Cmd {
         }
     })();
 
-    void new AstInspector(ctx);
-
-    ctx.pushCleanup(
+    ctx.pushExtCleanup(new AstInspector(ctx));
+    ctx.pushExtCleanup(
         vscode.workspace.registerTextDocumentContentProvider("rust-analyzer-syntax-tree", tdcp)
     );
-    ctx.pushCleanup(
+    ctx.pushExtCleanup(
         vscode.languages.setLanguageConfiguration("ra_syntax_tree", {
             brackets: [["[", ")"]],
         })
@@ -407,7 +402,7 @@ export function syntaxTree(ctx: Ctx): Cmd {
 // Opens the virtual file that will show the HIR of the function containing the cursor position
 //
 // The contents of the file come from the `TextDocumentContentProvider`
-export function viewHir(ctx: Ctx): Cmd {
+export function viewHir(ctx: CtxInit): Cmd {
     const tdcp = new (class implements vscode.TextDocumentContentProvider {
         readonly uri = vscode.Uri.parse("rust-analyzer-hir://viewHir/hir.rs");
         readonly eventEmitter = new vscode.EventEmitter<vscode.Uri>();
@@ -437,14 +432,14 @@ export function viewHir(ctx: Ctx): Cmd {
             }
         }
 
-        provideTextDocumentContent(
+        async provideTextDocumentContent(
             _uri: vscode.Uri,
             ct: vscode.CancellationToken
-        ): vscode.ProviderResult<string> {
+        ): Promise<string> {
             const rustEditor = ctx.activeRustEditor;
-            const client = ctx.client;
-            if (!rustEditor || !client) return "";
+            if (!rustEditor) return "";
 
+            const client = ctx.client;
             const params = {
                 textDocument: client.code2ProtocolConverter.asTextDocumentIdentifier(
                     rustEditor.document
@@ -459,7 +454,7 @@ export function viewHir(ctx: Ctx): Cmd {
         }
     })();
 
-    ctx.pushCleanup(
+    ctx.pushExtCleanup(
         vscode.workspace.registerTextDocumentContentProvider("rust-analyzer-hir", tdcp)
     );
 
@@ -473,7 +468,7 @@ export function viewHir(ctx: Ctx): Cmd {
     };
 }
 
-export function viewFileText(ctx: Ctx): Cmd {
+export function viewFileText(ctx: CtxInit): Cmd {
     const tdcp = new (class implements vscode.TextDocumentContentProvider {
         readonly uri = vscode.Uri.parse("rust-analyzer-file-text://viewFileText/file.rs");
         readonly eventEmitter = new vscode.EventEmitter<vscode.Uri>();
@@ -503,13 +498,13 @@ export function viewFileText(ctx: Ctx): Cmd {
             }
         }
 
-        provideTextDocumentContent(
+        async provideTextDocumentContent(
             _uri: vscode.Uri,
             ct: vscode.CancellationToken
-        ): vscode.ProviderResult<string> {
+        ): Promise<string> {
             const rustEditor = ctx.activeRustEditor;
+            if (!rustEditor) return "";
             const client = ctx.client;
-            if (!rustEditor || !client) return "";
 
             const params = client.code2ProtocolConverter.asTextDocumentIdentifier(
                 rustEditor.document
@@ -522,7 +517,7 @@ export function viewFileText(ctx: Ctx): Cmd {
         }
     })();
 
-    ctx.pushCleanup(
+    ctx.pushExtCleanup(
         vscode.workspace.registerTextDocumentContentProvider("rust-analyzer-file-text", tdcp)
     );
 
@@ -536,7 +531,7 @@ export function viewFileText(ctx: Ctx): Cmd {
     };
 }
 
-export function viewItemTree(ctx: Ctx): Cmd {
+export function viewItemTree(ctx: CtxInit): Cmd {
     const tdcp = new (class implements vscode.TextDocumentContentProvider {
         readonly uri = vscode.Uri.parse("rust-analyzer-item-tree://viewItemTree/itemtree.rs");
         readonly eventEmitter = new vscode.EventEmitter<vscode.Uri>();
@@ -566,13 +561,13 @@ export function viewItemTree(ctx: Ctx): Cmd {
             }
         }
 
-        provideTextDocumentContent(
+        async provideTextDocumentContent(
             _uri: vscode.Uri,
             ct: vscode.CancellationToken
-        ): vscode.ProviderResult<string> {
+        ): Promise<string> {
             const rustEditor = ctx.activeRustEditor;
+            if (!rustEditor) return "";
             const client = ctx.client;
-            if (!rustEditor || !client) return "";
 
             const params = {
                 textDocument: client.code2ProtocolConverter.asTextDocumentIdentifier(
@@ -587,7 +582,7 @@ export function viewItemTree(ctx: Ctx): Cmd {
         }
     })();
 
-    ctx.pushCleanup(
+    ctx.pushExtCleanup(
         vscode.workspace.registerTextDocumentContentProvider("rust-analyzer-item-tree", tdcp)
     );
 
@@ -601,7 +596,7 @@ export function viewItemTree(ctx: Ctx): Cmd {
     };
 }
 
-function crateGraph(ctx: Ctx, full: boolean): Cmd {
+function crateGraph(ctx: CtxInit, full: boolean): Cmd {
     return async () => {
         const nodeModulesPath = vscode.Uri.file(path.join(ctx.extensionPath, "node_modules"));
 
@@ -618,8 +613,8 @@ function crateGraph(ctx: Ctx, full: boolean): Cmd {
         const params = {
             full: full,
         };
-
-        const dot = await ctx.client.sendRequest(ra.viewCrateGraph, params);
+        const client = ctx.client;
+        const dot = await client.sendRequest(ra.viewCrateGraph, params);
         const uri = panel.webview.asWebviewUri(nodeModulesPath);
 
         const html = `
@@ -664,18 +659,18 @@ function crateGraph(ctx: Ctx, full: boolean): Cmd {
     };
 }
 
-export function viewCrateGraph(ctx: Ctx): Cmd {
+export function viewCrateGraph(ctx: CtxInit): Cmd {
     return crateGraph(ctx, false);
 }
 
-export function viewFullCrateGraph(ctx: Ctx): Cmd {
+export function viewFullCrateGraph(ctx: CtxInit): Cmd {
     return crateGraph(ctx, true);
 }
 
 // Opens the virtual file that will show the syntax tree
 //
 // The contents of the file come from the `TextDocumentContentProvider`
-export function expandMacro(ctx: Ctx): Cmd {
+export function expandMacro(ctx: CtxInit): Cmd {
     function codeFormat(expanded: ra.ExpandedMacro): string {
         let result = `// Recursive expansion of ${expanded.name}! macro\n`;
         result += "// " + "=".repeat(result.length - 3);
@@ -690,13 +685,13 @@ export function expandMacro(ctx: Ctx): Cmd {
         eventEmitter = new vscode.EventEmitter<vscode.Uri>();
         async provideTextDocumentContent(_uri: vscode.Uri): Promise<string> {
             const editor = vscode.window.activeTextEditor;
+            if (!editor) return "";
             const client = ctx.client;
-            if (!editor || !client) return "";
 
             const position = editor.selection.active;
 
             const expanded = await client.sendRequest(ra.expandMacro, {
-                textDocument: ctx.client.code2ProtocolConverter.asTextDocumentIdentifier(
+                textDocument: client.code2ProtocolConverter.asTextDocumentIdentifier(
                     editor.document
                 ),
                 position,
@@ -712,7 +707,7 @@ export function expandMacro(ctx: Ctx): Cmd {
         }
     })();
 
-    ctx.pushCleanup(
+    ctx.pushExtCleanup(
         vscode.workspace.registerTextDocumentContentProvider("rust-analyzer-expand-macro", tdcp)
     );
 
@@ -723,12 +718,12 @@ export function expandMacro(ctx: Ctx): Cmd {
     };
 }
 
-export function reloadWorkspace(ctx: Ctx): Cmd {
+export function reloadWorkspace(ctx: CtxInit): Cmd {
     return async () => ctx.client.sendRequest(ra.reloadWorkspace);
 }
 
 async function showReferencesImpl(
-    client: LanguageClient,
+    client: LanguageClient | undefined,
     uri: string,
     position: lc.Position,
     locations: lc.Location[]
@@ -743,13 +738,13 @@ async function showReferencesImpl(
     }
 }
 
-export function showReferences(ctx: Ctx): Cmd {
+export function showReferences(ctx: CtxInit): Cmd {
     return async (uri: string, position: lc.Position, locations: lc.Location[]) => {
         await showReferencesImpl(ctx.client, uri, position, locations);
     };
 }
 
-export function applyActionGroup(_ctx: Ctx): Cmd {
+export function applyActionGroup(_ctx: CtxInit): Cmd {
     return async (actions: { label: string; arguments: lc.CodeAction }[]) => {
         const selectedAction = await vscode.window.showQuickPick(actions);
         if (!selectedAction) return;
@@ -760,27 +755,25 @@ export function applyActionGroup(_ctx: Ctx): Cmd {
     };
 }
 
-export function gotoLocation(ctx: Ctx): Cmd {
+export function gotoLocation(ctx: CtxInit): Cmd {
     return async (locationLink: lc.LocationLink) => {
         const client = ctx.client;
-        if (client) {
-            const uri = client.protocol2CodeConverter.asUri(locationLink.targetUri);
-            let range = client.protocol2CodeConverter.asRange(locationLink.targetSelectionRange);
-            // collapse the range to a cursor position
-            range = range.with({ end: range.start });
+        const uri = client.protocol2CodeConverter.asUri(locationLink.targetUri);
+        let range = client.protocol2CodeConverter.asRange(locationLink.targetSelectionRange);
+        // collapse the range to a cursor position
+        range = range.with({ end: range.start });
 
-            await vscode.window.showTextDocument(uri, { selection: range });
-        }
+        await vscode.window.showTextDocument(uri, { selection: range });
     };
 }
 
-export function openDocs(ctx: Ctx): Cmd {
+export function openDocs(ctx: CtxInit): Cmd {
     return async () => {
-        const client = ctx.client;
         const editor = vscode.window.activeTextEditor;
-        if (!editor || !client) {
+        if (!editor) {
             return;
         }
+        const client = ctx.client;
 
         const position = editor.selection.active;
         const textDocument = { uri: editor.document.uri.toString() };
@@ -793,22 +786,23 @@ export function openDocs(ctx: Ctx): Cmd {
     };
 }
 
-export function cancelFlycheck(ctx: Ctx): Cmd {
+export function cancelFlycheck(ctx: CtxInit): Cmd {
     return async () => {
-        await ctx.client.sendRequest(ra.cancelFlycheck);
+        const client = ctx.client;
+        await client.sendRequest(ra.cancelFlycheck);
     };
 }
 
-export function resolveCodeAction(ctx: Ctx): Cmd {
-    const client = ctx.client;
+export function resolveCodeAction(ctx: CtxInit): Cmd {
     return async (params: lc.CodeAction) => {
+        const client = ctx.client;
         params.command = undefined;
-        const item = await client.sendRequest(lc.CodeActionResolveRequest.type, params);
-        if (!item.edit) {
+        const item = await client?.sendRequest(lc.CodeActionResolveRequest.type, params);
+        if (!item?.edit) {
             return;
         }
         const itemEdit = item.edit;
-        const edit = await client.protocol2CodeConverter.asWorkspaceEdit(itemEdit);
+        const edit = await client?.protocol2CodeConverter.asWorkspaceEdit(itemEdit);
         // filter out all text edits and recreate the WorkspaceEdit without them so we can apply
         // snippet edits on our own
         const lcFileSystemEdit = {
@@ -826,13 +820,13 @@ export function resolveCodeAction(ctx: Ctx): Cmd {
     };
 }
 
-export function applySnippetWorkspaceEditCommand(_ctx: Ctx): Cmd {
+export function applySnippetWorkspaceEditCommand(_ctx: CtxInit): Cmd {
     return async (edit: vscode.WorkspaceEdit) => {
         await applySnippetWorkspaceEdit(edit);
     };
 }
 
-export function run(ctx: Ctx): Cmd {
+export function run(ctx: CtxInit): Cmd {
     let prevRunnable: RunnableQuickPick | undefined;
 
     return async () => {
@@ -846,12 +840,11 @@ export function run(ctx: Ctx): Cmd {
     };
 }
 
-export function peekTests(ctx: Ctx): Cmd {
-    const client = ctx.client;
-
+export function peekTests(ctx: CtxInit): Cmd {
     return async () => {
         const editor = ctx.activeRustEditor;
-        if (!editor || !client) return;
+        if (!editor) return;
+        const client = ctx.client;
 
         await vscode.window.withProgress(
             {
@@ -880,7 +873,7 @@ export function peekTests(ctx: Ctx): Cmd {
     };
 }
 
-export function runSingle(ctx: Ctx): Cmd {
+export function runSingle(ctx: CtxInit): Cmd {
     return async (runnable: ra.Runnable) => {
         const editor = ctx.activeRustEditor;
         if (!editor) return;
@@ -897,7 +890,7 @@ export function runSingle(ctx: Ctx): Cmd {
     };
 }
 
-export function copyRunCommandLine(ctx: Ctx) {
+export function copyRunCommandLine(ctx: CtxInit) {
     let prevRunnable: RunnableQuickPick | undefined;
     return async () => {
         const item = await selectRunnable(ctx, prevRunnable);
@@ -909,7 +902,7 @@ export function copyRunCommandLine(ctx: Ctx) {
     };
 }
 
-export function debug(ctx: Ctx): Cmd {
+export function debug(ctx: CtxInit): Cmd {
     let prevDebuggee: RunnableQuickPick | undefined;
 
     return async () => {
@@ -922,13 +915,13 @@ export function debug(ctx: Ctx): Cmd {
     };
 }
 
-export function debugSingle(ctx: Ctx): Cmd {
+export function debugSingle(ctx: CtxInit): Cmd {
     return async (config: ra.Runnable) => {
         await startDebugSession(ctx, config);
     };
 }
 
-export function newDebugConfig(ctx: Ctx): Cmd {
+export function newDebugConfig(ctx: CtxInit): Cmd {
     return async () => {
         const item = await selectRunnable(ctx, undefined, true, false);
         if (!item) return;
@@ -937,10 +930,10 @@ export function newDebugConfig(ctx: Ctx): Cmd {
     };
 }
 
-export function linkToCommand(ctx: Ctx): Cmd {
+export function linkToCommand(_: Ctx): Cmd {
     return async (commandId: string) => {
         const link = LINKED_COMMANDS.get(commandId);
-        if (ctx.client && link) {
+        if (link) {
             const { command, arguments: args = [] } = link;
             await vscode.commands.executeCommand(command, ...args);
         }
diff --git a/src/tools/rust-analyzer/editors/code/src/config.ts b/src/tools/rust-analyzer/editors/code/src/config.ts
index 15846a5e8645..632a7d86faa3 100644
--- a/src/tools/rust-analyzer/editors/code/src/config.ts
+++ b/src/tools/rust-analyzer/editors/code/src/config.ts
@@ -1,4 +1,5 @@
-import path = require("path");
+import * as path from "path";
+import * as os from "os";
 import * as vscode from "vscode";
 import { Env } from "./client";
 import { log } from "./util";
@@ -10,23 +11,17 @@ export type RunnableEnvCfg =
 
 export class Config {
     readonly extensionId = "rust-lang.rust-analyzer";
+    configureLang: vscode.Disposable | undefined;
 
     readonly rootSection = "rust-analyzer";
-    private readonly requiresWorkspaceReloadOpts = [
-        "serverPath",
-        "server",
-        // FIXME: This shouldn't be here, changing this setting should reload
-        // `continueCommentsOnNewline` behavior without restart
-        "typing",
-    ].map((opt) => `${this.rootSection}.${opt}`);
     private readonly requiresReloadOpts = [
         "cargo",
         "procMacro",
+        "serverPath",
+        "server",
         "files",
         "lens", // works as lens.*
-    ]
-        .map((opt) => `${this.rootSection}.${opt}`)
-        .concat(this.requiresWorkspaceReloadOpts);
+    ].map((opt) => `${this.rootSection}.${opt}`);
 
     readonly package: {
         version: string;
@@ -44,6 +39,11 @@ export class Config {
             ctx.subscriptions
         );
         this.refreshLogging();
+        this.configureLanguage();
+    }
+
+    dispose() {
+        this.configureLang?.dispose();
     }
 
     private refreshLogging() {
@@ -57,33 +57,86 @@ export class Config {
     private async onDidChangeConfiguration(event: vscode.ConfigurationChangeEvent) {
         this.refreshLogging();
 
+        this.configureLanguage();
+
         const requiresReloadOpt = this.requiresReloadOpts.find((opt) =>
             event.affectsConfiguration(opt)
         );
 
         if (!requiresReloadOpt) return;
 
-        const requiresWorkspaceReloadOpt = this.requiresWorkspaceReloadOpts.find((opt) =>
-            event.affectsConfiguration(opt)
-        );
-
-        if (!requiresWorkspaceReloadOpt && this.restartServerOnConfigChange) {
+        if (this.restartServerOnConfigChange) {
             await vscode.commands.executeCommand("rust-analyzer.reload");
             return;
         }
 
-        const message = requiresWorkspaceReloadOpt
-            ? `Changing "${requiresWorkspaceReloadOpt}" requires a window reload`
-            : `Changing "${requiresReloadOpt}" requires a reload`;
-        const userResponse = await vscode.window.showInformationMessage(message, "Reload now");
+        const message = `Changing "${requiresReloadOpt}" requires a server restart`;
+        const userResponse = await vscode.window.showInformationMessage(message, "Restart now");
 
-        if (userResponse === "Reload now") {
-            const command = requiresWorkspaceReloadOpt
-                ? "workbench.action.reloadWindow"
-                : "rust-analyzer.reload";
-            if (userResponse === "Reload now") {
-                await vscode.commands.executeCommand(command);
-            }
+        if (userResponse) {
+            const command = "rust-analyzer.reload";
+            await vscode.commands.executeCommand(command);
+        }
+    }
+
+    /**
+     * Sets up additional language configuration that's impossible to do via a
+     * separate language-configuration.json file. See [1] for more information.
+     *
+     * [1]: https://github.com/Microsoft/vscode/issues/11514#issuecomment-244707076
+     */
+    private configureLanguage() {
+        if (this.typingContinueCommentsOnNewline && !this.configureLang) {
+            const indentAction = vscode.IndentAction.None;
+
+            this.configureLang = vscode.languages.setLanguageConfiguration("rust", {
+                onEnterRules: [
+                    {
+                        // Doc single-line comment
+                        // e.g. ///|
+                        beforeText: /^\s*\/{3}.*$/,
+                        action: { indentAction, appendText: "/// " },
+                    },
+                    {
+                        // Parent doc single-line comment
+                        // e.g. //!|
+                        beforeText: /^\s*\/{2}\!.*$/,
+                        action: { indentAction, appendText: "//! " },
+                    },
+                    {
+                        // Begins an auto-closed multi-line comment (standard or parent doc)
+                        // e.g. /** | */ or /*! | */
+                        beforeText: /^\s*\/\*(\*|\!)(?!\/)([^\*]|\*(?!\/))*$/,
+                        afterText: /^\s*\*\/$/,
+                        action: {
+                            indentAction: vscode.IndentAction.IndentOutdent,
+                            appendText: " * ",
+                        },
+                    },
+                    {
+                        // Begins a multi-line comment (standard or parent doc)
+                        // e.g. /** ...| or /*! ...|
+                        beforeText: /^\s*\/\*(\*|\!)(?!\/)([^\*]|\*(?!\/))*$/,
+                        action: { indentAction, appendText: " * " },
+                    },
+                    {
+                        // Continues a multi-line comment
+                        // e.g.  * ...|
+                        beforeText: /^(\ \ )*\ \*(\ ([^\*]|\*(?!\/))*)?$/,
+                        action: { indentAction, appendText: "* " },
+                    },
+                    {
+                        // Dedents after closing a multi-line comment
+                        // e.g.  */|
+                        beforeText: /^(\ \ )*\ \*\/\s*$/,
+                        action: { indentAction, removeText: 1 },
+                    },
+                ],
+            });
+        }
+        if (!this.typingContinueCommentsOnNewline && this.configureLang) {
+            this.configureLang.dispose();
+            this.configureLang = undefined;
         }
     }
 
@@ -187,6 +240,37 @@ export class Config {
     }
 }
 
+const VarRegex = new RegExp(/\$\{(.+?)\}/g);
+
+export function substituteVSCodeVariableInString(val: string): string {
+    return val.replace(VarRegex, (substring: string, varName) => {
+        if (typeof varName === "string") {
+            return computeVscodeVar(varName) || substring;
+        } else {
+            return substring;
+        }
+    });
+}
+
+export function substituteVSCodeVariables(resp: any): any {
+    if (typeof resp === "string") {
+        return substituteVSCodeVariableInString(resp);
+    } else if (resp && Array.isArray(resp)) {
+        return resp.map((val) => {
+            return substituteVSCodeVariables(val);
+        });
+    } else if (resp && typeof resp === "object") {
+        const res: { [key: string]: any } = {};
+        for (const key in resp) {
+            const val = resp[key];
+            res[key] = substituteVSCodeVariables(val);
+        }
+        return res;
+    } else if (typeof resp === "function") {
+        return null;
+    }
+    return resp;
+}
 export function substituteVariablesInEnv(env: Env): Env {
     const missingDeps = new Set<string>();
     // vscode uses `env:ENV_NAME` for env vars resolution, and it's easier
@@ -233,7 +317,7 @@ export function substituteVariablesInEnv(env: Env): Env {
             }
         } else {
             envWithDeps[dep] = {
-                value: computeVscodeVar(dep),
+                value: computeVscodeVar(dep) || "${" + dep + "}",
                 deps: [],
             };
         }
@@ -264,37 +348,34 @@ export function substituteVariablesInEnv(env: Env): Env {
     return resolvedEnv;
 }
 
-function computeVscodeVar(varName: string): string {
+function computeVscodeVar(varName: string): string | null {
+    const workspaceFolder = () => {
+        const folders = vscode.workspace.workspaceFolders ?? [];
+        if (folders.length === 1) {
+            // TODO: support for remote workspaces?
+            return folders[0].uri.fsPath;
+        } else if (folders.length > 1) {
+            // could use currently opened document to detect the correct
+            // workspace. However, that would be determined by the document
+            // user has opened on Editor startup. Could lead to
+            // unpredictable workspace selection in practice.
+            // It's better to pick the first one
+            return folders[0].uri.fsPath;
+        } else {
+            // no workspace opened
+            return "";
+        }
+    };
     // https://code.visualstudio.com/docs/editor/variables-reference
     const supportedVariables: { [k: string]: () => string } = {
-        workspaceFolder: () => {
-            const folders = vscode.workspace.workspaceFolders ?? [];
-            if (folders.length === 1) {
-                // TODO: support for remote workspaces?
-                return folders[0].uri.fsPath;
-            } else if (folders.length > 1) {
-                // could use currently opened document to detect the correct
-                // workspace. However, that would be determined by the document
-                // user has opened on Editor startup. Could lead to
-                // unpredictable workspace selection in practice.
-                // It's better to pick the first one
-                return folders[0].uri.fsPath;
-            } else {
-                // no workspace opened
-                return "";
-            }
-        },
+        workspaceFolder,
 
         workspaceFolderBasename: () => {
-            const workspaceFolder = computeVscodeVar("workspaceFolder");
-            if (workspaceFolder) {
-                return path.basename(workspaceFolder);
-            } else {
-                return "";
-            }
+            return path.basename(workspaceFolder());
         },
 
         cwd: () => process.cwd(),
+        userHome: () => os.homedir(),
 
         // see
         // https://github.com/microsoft/vscode/blob/08ac1bb67ca2459496b272d8f4a908757f24f56f/src/vs/workbench/api/common/extHostVariableResolverService.ts#L81
@@ -308,7 +389,7 @@ function computeVscodeVar(varName: string): string {
     if (varName in supportedVariables) {
         return supportedVariables[varName]();
     } else {
-        // can't resolve, keep the expression as is
-        return "${" + varName + "}";
+        // return "${" + varName + "}";
+        return null;
     }
 }
diff --git a/src/tools/rust-analyzer/editors/code/src/ctx.ts b/src/tools/rust-analyzer/editors/code/src/ctx.ts
index 26510011d439..3e366525ee29 100644
--- a/src/tools/rust-analyzer/editors/code/src/ctx.ts
+++ b/src/tools/rust-analyzer/editors/code/src/ctx.ts
@@ -2,12 +2,19 @@ import * as vscode from "vscode";
 import * as lc from "vscode-languageclient/node";
 import * as ra from "./lsp_ext";
 
-import { Config } from "./config";
+import { Config, substituteVariablesInEnv, substituteVSCodeVariables } from "./config";
 import { createClient } from "./client";
-import { isRustEditor, RustEditor } from "./util";
+import { isRustDocument, isRustEditor, log, RustEditor } from "./util";
 import { ServerStatusParams } from "./lsp_ext";
+import { PersistentState } from "./persistent_state";
+import { bootstrap } from "./bootstrap";
+
+// We only support local folders, not eg. Live Share (`vlsl:` scheme), so don't activate if
+// only those are in use. We use "Empty" to represent these scenarios
+// (r-a still somewhat works with Live Share, because commands are tunneled to the host)
 
 export type Workspace =
+    | { kind: "Empty" }
     | {
           kind: "Workspace Folder";
       }
@@ -16,36 +23,213 @@ export type Workspace =
           files: vscode.TextDocument[];
       };
 
+export function fetchWorkspace(): Workspace {
+    const folders = (vscode.workspace.workspaceFolders || []).filter(
+        (folder) => folder.uri.scheme === "file"
+    );
+    const rustDocuments = vscode.workspace.textDocuments.filter((document) =>
+        isRustDocument(document)
+    );
+
+    return folders.length === 0
+        ? rustDocuments.length === 0
+            ? { kind: "Empty" }
+            : {
+                  kind: "Detached Files",
+                  files: rustDocuments,
+              }
+        : { kind: "Workspace Folder" };
+}
+
+export type CommandFactory = {
+    enabled: (ctx: CtxInit) => Cmd;
+    disabled?: (ctx: Ctx) => Cmd;
+};
+
+export type CtxInit = Ctx & {
+    readonly client: lc.LanguageClient;
+};
+
 export class Ctx {
-    private constructor(
-        readonly config: Config,
-        private readonly extCtx: vscode.ExtensionContext,
-        readonly client: lc.LanguageClient,
-        readonly serverPath: string,
-        readonly statusBar: vscode.StatusBarItem
-    ) {}
+    readonly statusBar: vscode.StatusBarItem;
+    readonly config: Config;
+    readonly workspace: Workspace;
 
-    static async create(
-        config: Config,
-        extCtx: vscode.ExtensionContext,
-        serverPath: string,
+    private _client: lc.LanguageClient | undefined;
+    private _serverPath: string | undefined;
+    private traceOutputChannel: vscode.OutputChannel | undefined;
+    private outputChannel: vscode.OutputChannel | undefined;
+    private clientSubscriptions: Disposable[];
+    private state: PersistentState;
+    private commandFactories: Record<string, CommandFactory>;
+    private commandDisposables: Disposable[];
+
+    get client() {
+        return this._client;
+    }
+
+    constructor(
+        readonly extCtx: vscode.ExtensionContext,
+        commandFactories: Record<string, CommandFactory>,
         workspace: Workspace
-    ): Promise<Ctx> {
-        const client = await createClient(serverPath, workspace, config.serverExtraEnv);
+    ) {
+        extCtx.subscriptions.push(this);
+        this.statusBar = vscode.window.createStatusBarItem(vscode.StatusBarAlignment.Left);
+        this.statusBar.show();
+        this.workspace = workspace;
+        this.clientSubscriptions = [];
+        this.commandDisposables = [];
+        this.commandFactories = commandFactories;
 
-        const statusBar = vscode.window.createStatusBarItem(vscode.StatusBarAlignment.Left);
-        extCtx.subscriptions.push(statusBar);
-        statusBar.text = "rust-analyzer";
-        statusBar.tooltip = "ready";
-        statusBar.command = "rust-analyzer.analyzerStatus";
-        statusBar.show();
+        this.state = new PersistentState(extCtx.globalState);
+        this.config = new Config(extCtx);
 
-        const res = new Ctx(config, extCtx, client, serverPath, statusBar);
+        this.updateCommands("disable");
+        this.setServerStatus({
+            health: "stopped",
+        });
+    }
 
-        res.pushCleanup(client.start());
-        await client.onReady();
-        client.onNotification(ra.serverStatus, (params) => res.setServerStatus(params));
-        return res;
+    dispose() {
+        this.config.dispose();
+        this.statusBar.dispose();
+        void this.disposeClient();
+        this.commandDisposables.forEach((disposable) => disposable.dispose());
+    }
+
+    async onWorkspaceFolderChanges() {
+        const workspace = fetchWorkspace();
+        if (workspace.kind === "Detached Files" && this.workspace.kind === "Detached Files") {
+            if (workspace.files !== this.workspace.files) {
+                if (this.client?.isRunning()) {
+                    // Ideally we wouldn't need to tear down the server here, but currently detached files
+                    // are only specified at server start
+                    await this.stopAndDispose();
+                    await this.start();
+                }
+                return;
+            }
+        }
+        if (workspace.kind === "Workspace Folder" && this.workspace.kind === "Workspace Folder") {
+            return;
+        }
+        if (workspace.kind === "Empty") {
+            await this.stopAndDispose();
+            return;
+        }
+        if (this.client?.isRunning()) {
+            await this.restart();
+        }
+    }
+
+    private async getOrCreateClient() {
+        if (this.workspace.kind === "Empty") {
+            return;
+        }
+
+        if (!this.traceOutputChannel) {
+            this.traceOutputChannel = vscode.window.createOutputChannel(
+                "Rust Analyzer Language Server Trace"
+            );
+            this.pushExtCleanup(this.traceOutputChannel);
+        }
+        if (!this.outputChannel) {
+            this.outputChannel = vscode.window.createOutputChannel("Rust Analyzer Language Server");
+            this.pushExtCleanup(this.outputChannel);
+        }
+
+        if (!this._client) {
+            this._serverPath = await bootstrap(this.extCtx, this.config, this.state).catch(
+                (err) => {
+                    let message = "bootstrap error. ";
+
+                    message +=
+                        'See the logs in "OUTPUT > Rust Analyzer Client" (should open automatically). ';
+                    message +=
+                        'To enable verbose logs use { "rust-analyzer.trace.extension": true }';
+
+                    log.error("Bootstrap error", err);
+                    throw new Error(message);
+                }
+            );
+            const newEnv = substituteVariablesInEnv(
+                Object.assign({}, process.env, this.config.serverExtraEnv)
+            );
+            const run: lc.Executable = {
+                command: this._serverPath,
+                options: { env: newEnv },
+            };
+            const serverOptions = {
+                run,
+                debug: run,
+            };
+
+            let rawInitializationOptions = vscode.workspace.getConfiguration("rust-analyzer");
+
+            if (this.workspace.kind === "Detached Files") {
+                rawInitializationOptions = {
+                    detachedFiles: this.workspace.files.map((file) => file.uri.fsPath),
+                    ...rawInitializationOptions,
+                };
+            }
+
+            const initializationOptions = substituteVSCodeVariables(rawInitializationOptions);
+
+            this._client = await createClient(
+                this.traceOutputChannel,
+                this.outputChannel,
+                initializationOptions,
+                serverOptions
+            );
+            this.pushClientCleanup(
+                this._client.onNotification(ra.serverStatus, (params) =>
+                    this.setServerStatus(params)
+                )
+            );
+        }
+        return this._client;
+    }
+
+    async start() {
+        log.info("Starting language client");
+        const client = await this.getOrCreateClient();
+        if (!client) {
+            return;
+        }
+        await client.start();
+        this.updateCommands();
+    }
+
+    async restart() {
+        // FIXME: We should re-use the client, that is ctx.deactivate() if none of the configs have changed
+        await this.stopAndDispose();
+        await this.start();
+    }
+
+    async stop() {
+        if (!this._client) {
+            return;
+        }
+        log.info("Stopping language client");
+        this.updateCommands("disable");
+        await this._client.stop();
+    }
+
+    async stopAndDispose() {
+        if (!this._client) {
+            return;
+        }
+        log.info("Disposing language client");
+        this.updateCommands("disable");
+        await this.disposeClient();
+    }
+
+    private async disposeClient() {
+        this.clientSubscriptions?.forEach((disposable) => disposable.dispose());
+        this.clientSubscriptions = [];
+        await this._client?.dispose();
+        this._serverPath = undefined;
+        this._client = undefined;
     }
 
     get activeRustEditor(): RustEditor | undefined {
@@ -53,36 +237,53 @@ export class Ctx {
         return editor && isRustEditor(editor) ? editor : undefined;
     }
 
-    get visibleRustEditors(): RustEditor[] {
-        return vscode.window.visibleTextEditors.filter(isRustEditor);
-    }
-
-    registerCommand(name: string, factory: (ctx: Ctx) => Cmd) {
-        const fullName = `rust-analyzer.${name}`;
-        const cmd = factory(this);
-        const d = vscode.commands.registerCommand(fullName, cmd);
-        this.pushCleanup(d);
-    }
-
     get extensionPath(): string {
         return this.extCtx.extensionPath;
     }
 
-    get globalState(): vscode.Memento {
-        return this.extCtx.globalState;
-    }
-
     get subscriptions(): Disposable[] {
         return this.extCtx.subscriptions;
     }
 
-    setServerStatus(status: ServerStatusParams) {
+    get serverPath(): string | undefined {
+        return this._serverPath;
+    }
+
+    private updateCommands(forceDisable?: "disable") {
+        this.commandDisposables.forEach((disposable) => disposable.dispose());
+        this.commandDisposables = [];
+
+        const clientRunning = (!forceDisable && this._client?.isRunning()) ?? false;
+        const isClientRunning = function (_ctx: Ctx): _ctx is CtxInit {
+            return clientRunning;
+        };
+
+        for (const [name, factory] of Object.entries(this.commandFactories)) {
+            const fullName = `rust-analyzer.${name}`;
+            let callback;
+            if (isClientRunning(this)) {
+                // we asserted that `client` is defined
+                callback = factory.enabled(this);
+            } else if (factory.disabled) {
+                callback = factory.disabled(this);
+            } else {
+                callback = () =>
+                    vscode.window.showErrorMessage(
+                        `command ${fullName} failed: rust-analyzer server is not running`
+                    );
+            }
+
+            this.commandDisposables.push(vscode.commands.registerCommand(fullName, callback));
+        }
+    }
+
+    setServerStatus(status: ServerStatusParams | { health: "stopped" }) {
         let icon = "";
         const statusBar = this.statusBar;
         switch (status.health) {
             case "ok":
-                statusBar.tooltip = status.message ?? "Ready";
-                statusBar.command = undefined;
+                statusBar.tooltip = (status.message ?? "Ready") + "\nClick to stop server.";
+                statusBar.command = "rust-analyzer.stopServer";
                 statusBar.color = undefined;
                 statusBar.backgroundColor = undefined;
                 break;
@@ -106,14 +307,25 @@ export class Ctx {
                 statusBar.backgroundColor = new vscode.ThemeColor("statusBarItem.errorBackground");
                 icon = "$(error) ";
                 break;
+            case "stopped":
+                statusBar.tooltip = "Server is stopped.\nClick to start.";
+                statusBar.command = "rust-analyzer.startServer";
+                statusBar.color = undefined;
+                statusBar.backgroundColor = undefined;
+                statusBar.text = `$(stop-circle) rust-analyzer`;
+                return;
         }
         if (!status.quiescent) icon = "$(sync~spin) ";
         statusBar.text = `${icon}rust-analyzer`;
     }
 
-    pushCleanup(d: Disposable) {
+    pushExtCleanup(d: Disposable) {
         this.extCtx.subscriptions.push(d);
     }
+
+    private pushClientCleanup(d: Disposable) {
+        this.clientSubscriptions.push(d);
+    }
 }
 
 export interface Disposable {
diff --git a/src/tools/rust-analyzer/editors/code/src/main.ts b/src/tools/rust-analyzer/editors/code/src/main.ts
index 41bde4195e07..e76b657c1bfb 100644
--- a/src/tools/rust-analyzer/editors/code/src/main.ts
+++ b/src/tools/rust-analyzer/editors/code/src/main.ts
@@ -1,356 +1,24 @@
 import * as vscode from "vscode";
 import * as lc from "vscode-languageclient/node";
-import * as os from "os";
 
 import * as commands from "./commands";
-import { Ctx } from "./ctx";
-import { Config } from "./config";
-import { log, isValidExecutable, isRustDocument } from "./util";
-import { PersistentState } from "./persistent_state";
+import { CommandFactory, Ctx, fetchWorkspace } from "./ctx";
 import { activateTaskProvider } from "./tasks";
 import { setContextValue } from "./util";
-import { exec } from "child_process";
-
-let ctx: Ctx | undefined;
 
 const RUST_PROJECT_CONTEXT_NAME = "inRustProject";
 
-let TRACE_OUTPUT_CHANNEL: vscode.OutputChannel | null = null;
-export function traceOutputChannel() {
-    if (!TRACE_OUTPUT_CHANNEL) {
-        TRACE_OUTPUT_CHANNEL = vscode.window.createOutputChannel(
-            "Rust Analyzer Language Server Trace"
-        );
-    }
-    return TRACE_OUTPUT_CHANNEL;
-}
-let OUTPUT_CHANNEL: vscode.OutputChannel | null = null;
-export function outputChannel() {
-    if (!OUTPUT_CHANNEL) {
-        OUTPUT_CHANNEL = vscode.window.createOutputChannel("Rust Analyzer Language Server");
-    }
-    return OUTPUT_CHANNEL;
+export interface RustAnalyzerExtensionApi {
+    readonly client?: lc.LanguageClient;
 }
 
-export interface RustAnalyzerExtensionApi {
-    client?: lc.LanguageClient;
+export async function deactivate() {
+    await setContextValue(RUST_PROJECT_CONTEXT_NAME, undefined);
 }
 
 export async function activate(
     context: vscode.ExtensionContext
 ): Promise<RustAnalyzerExtensionApi> {
-    // VS Code doesn't show a notification when an extension fails to activate
-    // so we do it ourselves.
-    return await tryActivate(context).catch((err) => {
-        void vscode.window.showErrorMessage(`Cannot activate rust-analyzer: ${err.message}`);
-        throw err;
-    });
-}
-
-async function tryActivate(context: vscode.ExtensionContext): Promise<RustAnalyzerExtensionApi> {
-    // We only support local folders, not eg. Live Share (`vlsl:` scheme), so don't activate if
-    // only those are in use.
-    // (r-a still somewhat works with Live Share, because commands are tunneled to the host)
-    const folders = (vscode.workspace.workspaceFolders || []).filter(
-        (folder) => folder.uri.scheme === "file"
-    );
-    const rustDocuments = vscode.workspace.textDocuments.filter((document) =>
-        isRustDocument(document)
-    );
-
-    if (folders.length === 0 && rustDocuments.length === 0) {
-        // FIXME: Ideally we would choose not to activate at all (and avoid registering
-        // non-functional editor commands), but VS Code doesn't seem to have a good way of doing
-        // that
-        return {};
-    }
-
-    const config = new Config(context);
-    const state = new PersistentState(context.globalState);
-    const serverPath = await bootstrap(context, config, state).catch((err) => {
-        let message = "bootstrap error. ";
-
-        message += 'See the logs in "OUTPUT > Rust Analyzer Client" (should open automatically). ';
-        message += 'To enable verbose logs use { "rust-analyzer.trace.extension": true }';
-
-        log.error("Bootstrap error", err);
-        throw new Error(message);
-    });
-
-    if (folders.length === 0) {
-        ctx = await Ctx.create(config, context, serverPath, {
-            kind: "Detached Files",
-            files: rustDocuments,
-        });
-    } else {
-        // Note: we try to start the server before we activate type hints so that it
-        // registers its `onDidChangeDocument` handler before us.
-        //
-        // This a horribly, horribly wrong way to deal with this problem.
-        ctx = await Ctx.create(config, context, serverPath, { kind: "Workspace Folder" });
-        ctx.pushCleanup(activateTaskProvider(ctx.config));
-    }
-    await initCommonContext(context, ctx);
-
-    warnAboutExtensionConflicts();
-
-    if (config.typingContinueCommentsOnNewline) {
-        ctx.pushCleanup(configureLanguage());
-    }
-
-    vscode.workspace.onDidChangeConfiguration(
-        (_) =>
-            ctx?.client
-                ?.sendNotification("workspace/didChangeConfiguration", { settings: "" })
-                .catch(log.error),
-        null,
-        ctx.subscriptions
-    );
-
-    return {
-        client: ctx.client,
-    };
-}
-
-async function initCommonContext(context: vscode.ExtensionContext, ctx: Ctx) {
-    // Register a "dumb" onEnter command for the case where server fails to
-    // start.
-    //
-    // FIXME: refactor command registration code such that commands are
-    // **always** registered, even if the server does not start. Use API like
-    // this perhaps?
-    //
-    // ```TypeScript
-    // registerCommand(
-    //    factory: (Ctx) => ((Ctx) => any),
-    //    fallback: () => any = () => vscode.window.showErrorMessage(
-    //        "rust-analyzer is not available"
-    //    ),
-    // )
-    const defaultOnEnter = vscode.commands.registerCommand("rust-analyzer.onEnter", () =>
-        vscode.commands.executeCommand("default:type", { text: "\n" })
-    );
-    context.subscriptions.push(defaultOnEnter);
-
-    await setContextValue(RUST_PROJECT_CONTEXT_NAME, true);
-
-    // Commands which invokes manually via command palette, shortcut, etc.
-
-    // Reloading is inspired by @DanTup maneuver: https://github.com/microsoft/vscode/issues/45774#issuecomment-373423895
-    ctx.registerCommand("reload", (_) => async () => {
-        void vscode.window.showInformationMessage("Reloading rust-analyzer...");
-        await doDeactivate();
-        while (context.subscriptions.length > 0) {
-            try {
-                context.subscriptions.pop()!.dispose();
-            } catch (err) {
-                log.error("Dispose error:", err);
-            }
-        }
-        await activate(context).catch(log.error);
-    });
-
-    ctx.registerCommand("analyzerStatus", commands.analyzerStatus);
-    ctx.registerCommand("memoryUsage", commands.memoryUsage);
-    ctx.registerCommand("shuffleCrateGraph", commands.shuffleCrateGraph);
-    ctx.registerCommand("reloadWorkspace", commands.reloadWorkspace);
-    ctx.registerCommand("matchingBrace", commands.matchingBrace);
-    ctx.registerCommand("joinLines", commands.joinLines);
-    ctx.registerCommand("parentModule", commands.parentModule);
-    ctx.registerCommand("syntaxTree", commands.syntaxTree);
-    ctx.registerCommand("viewHir", commands.viewHir);
-    ctx.registerCommand("viewFileText", commands.viewFileText);
-    ctx.registerCommand("viewItemTree", commands.viewItemTree);
-    ctx.registerCommand("viewCrateGraph", commands.viewCrateGraph);
-    ctx.registerCommand("viewFullCrateGraph", commands.viewFullCrateGraph);
-    ctx.registerCommand("expandMacro", commands.expandMacro);
-    ctx.registerCommand("run", commands.run);
-    ctx.registerCommand("copyRunCommandLine", commands.copyRunCommandLine);
-    ctx.registerCommand("debug", commands.debug);
-    ctx.registerCommand("newDebugConfig", commands.newDebugConfig);
-    ctx.registerCommand("openDocs", commands.openDocs);
-    ctx.registerCommand("openCargoToml", commands.openCargoToml);
-    ctx.registerCommand("peekTests", commands.peekTests);
-    ctx.registerCommand("moveItemUp", commands.moveItemUp);
-    ctx.registerCommand("moveItemDown", commands.moveItemDown);
-    ctx.registerCommand("cancelFlycheck", commands.cancelFlycheck);
-
-    defaultOnEnter.dispose();
-    ctx.registerCommand("onEnter", commands.onEnter);
-
-    ctx.registerCommand("ssr", commands.ssr);
-    ctx.registerCommand("serverVersion", commands.serverVersion);
-
-    // Internal commands which are invoked by the server.
-    ctx.registerCommand("runSingle", commands.runSingle);
-    ctx.registerCommand("debugSingle", commands.debugSingle);
-    ctx.registerCommand("showReferences", commands.showReferences);
-    ctx.registerCommand("applySnippetWorkspaceEdit", commands.applySnippetWorkspaceEditCommand);
-    ctx.registerCommand("resolveCodeAction", commands.resolveCodeAction);
-    ctx.registerCommand("applyActionGroup", commands.applyActionGroup);
-    ctx.registerCommand("gotoLocation", commands.gotoLocation);
-
-    ctx.registerCommand("linkToCommand", commands.linkToCommand);
-}
-
-export async function deactivate() {
-    TRACE_OUTPUT_CHANNEL?.dispose();
-    TRACE_OUTPUT_CHANNEL = null;
-    OUTPUT_CHANNEL?.dispose();
-    OUTPUT_CHANNEL = null;
-    await doDeactivate();
-}
-
-async function doDeactivate() {
-    await setContextValue(RUST_PROJECT_CONTEXT_NAME, undefined);
-    await ctx?.client.stop();
-    ctx = undefined;
-}
-
-async function bootstrap(
-    context: vscode.ExtensionContext,
-    config: Config,
-    state: PersistentState
-): Promise<string> {
-    const path = await getServer(context, config, state);
-    if (!path) {
-        throw new Error(
-            "Rust Analyzer Language Server is not available. " +
-                "Please, ensure its [proper installation](https://rust-analyzer.github.io/manual.html#installation)."
-        );
-    }
-
-    log.info("Using server binary at", path);
-
-    if (!isValidExecutable(path)) {
-        if (config.serverPath) {
-            throw new Error(`Failed to execute ${path} --version. \`config.server.path\` or \`config.serverPath\` has been set explicitly.\
-            Consider removing this config or making a valid server binary available at that path.`);
-        } else {
-            throw new Error(`Failed to execute ${path} --version`);
-        }
-    }
-
-    return path;
-}
-
-async function patchelf(dest: vscode.Uri): Promise<void> {
-    await vscode.window.withProgress(
-        {
-            location: vscode.ProgressLocation.Notification,
-            title: "Patching rust-analyzer for NixOS",
-        },
-        async (progress, _) => {
-            const expression = `
-            {srcStr, pkgs ? import <nixpkgs> {}}:
-                pkgs.stdenv.mkDerivation {
-                    name = "rust-analyzer";
-                    src = /. + srcStr;
-                    phases = [ "installPhase" "fixupPhase" ];
-                    installPhase = "cp $src $out";
-                    fixupPhase = ''
-                    chmod 755 $out
-                    patchelf --set-interpreter "$(cat $NIX_CC/nix-support/dynamic-linker)" $out
-                    '';
-                }
-            `;
-            const origFile = vscode.Uri.file(dest.fsPath + "-orig");
-            await vscode.workspace.fs.rename(dest, origFile, { overwrite: true });
-            try {
-                progress.report({ message: "Patching executable", increment: 20 });
-                await new Promise((resolve, reject) => {
-                    const handle = exec(
-                        `nix-build -E - --argstr srcStr '${origFile.fsPath}' -o '${dest.fsPath}'`,
-                        (err, stdout, stderr) => {
-                            if (err != null) {
-                                reject(Error(stderr));
-                            } else {
-                                resolve(stdout);
-                            }
-                        }
-                    );
-                    handle.stdin?.write(expression);
-                    handle.stdin?.end();
-                });
-            } finally {
-                await vscode.workspace.fs.delete(origFile);
-            }
-        }
-    );
-}
-
-async function getServer(
-    context: vscode.ExtensionContext,
-    config: Config,
-    state: PersistentState
-): Promise<string | undefined> {
-    const explicitPath = serverPath(config);
-    if (explicitPath) {
-        if (explicitPath.startsWith("~/")) {
-            return os.homedir() + explicitPath.slice("~".length);
-        }
-        return explicitPath;
-    }
-    if (config.package.releaseTag === null) return "rust-analyzer";
-
-    const ext = process.platform === "win32" ? ".exe" : "";
-    const bundled = vscode.Uri.joinPath(context.extensionUri, "server", `rust-analyzer${ext}`);
-    const bundledExists = await vscode.workspace.fs.stat(bundled).then(
-        () => true,
-        () => false
-    );
-    if (bundledExists) {
-        let server = bundled;
-        if (await isNixOs()) {
-            await vscode.workspace.fs.createDirectory(config.globalStorageUri).then();
-            const dest = vscode.Uri.joinPath(config.globalStorageUri, `rust-analyzer${ext}`);
-            let exists = await vscode.workspace.fs.stat(dest).then(
-                () => true,
-                () => false
-            );
-            if (exists && config.package.version !== state.serverVersion) {
-                await vscode.workspace.fs.delete(dest);
-                exists = false;
-            }
-            if (!exists) {
-                await vscode.workspace.fs.copy(bundled, dest);
-                await patchelf(dest);
-            }
-            server = dest;
-        }
-        await state.updateServerVersion(config.package.version);
-        return server.fsPath;
-    }
-
-    await state.updateServerVersion(undefined);
-    await vscode.window.showErrorMessage(
-        "Unfortunately we don't ship binaries for your platform yet. " +
-            "You need to manually clone the rust-analyzer repository and " +
-            "run `cargo xtask install --server` to build the language server from sources. " +
-            "If you feel that your platform should be supported, please create an issue " +
-            "about that [here](https://github.com/rust-lang/rust-analyzer/issues) and we " +
-            "will consider it."
-    );
-    return undefined;
-}
-
-function serverPath(config: Config): string | null {
-    return process.env.__RA_LSP_SERVER_DEBUG ?? config.serverPath;
-}
-
-async function isNixOs(): Promise<boolean> {
-    try {
-        const contents = (
-            await vscode.workspace.fs.readFile(vscode.Uri.file("/etc/os-release"))
-        ).toString();
-        const idString = contents.split("\n").find((a) => a.startsWith("ID=")) || "ID=linux";
-        return idString.indexOf("nixos") !== -1;
-    } catch {
-        return false;
-    }
-}
-
-function warnAboutExtensionConflicts() {
     if (vscode.extensions.getExtension("rust-lang.rust")) {
         vscode.window
             .showWarningMessage(
@@ -361,55 +29,113 @@ function warnAboutExtensionConflicts() {
             )
             .then(() => {}, console.error);
     }
+
+    const ctx = new Ctx(context, createCommands(), fetchWorkspace());
+    // VS Code doesn't show a notification when an extension fails to activate
+    // so we do it ourselves.
+    const api = await activateServer(ctx).catch((err) => {
+        void vscode.window.showErrorMessage(
+            `Cannot activate rust-analyzer extension: ${err.message}`
+        );
+        throw err;
+    });
+    await setContextValue(RUST_PROJECT_CONTEXT_NAME, true);
+    return api;
 }
 
-/**
- * Sets up additional language configuration that's impossible to do via a
- * separate language-configuration.json file. See [1] for more information.
- *
- * [1]: https://github.com/Microsoft/vscode/issues/11514#issuecomment-244707076
- */
-function configureLanguage(): vscode.Disposable {
-    const indentAction = vscode.IndentAction.None;
-    return vscode.languages.setLanguageConfiguration("rust", {
-        onEnterRules: [
-            {
-                // Doc single-line comment
-                // e.g. ///|
-                beforeText: /^\s*\/{3}.*$/,
-                action: { indentAction, appendText: "/// " },
-            },
-            {
-                // Parent doc single-line comment
-                // e.g. //!|
-                beforeText: /^\s*\/{2}\!.*$/,
-                action: { indentAction, appendText: "//! " },
-            },
-            {
-                // Begins an auto-closed multi-line comment (standard or parent doc)
-                // e.g. /** | */ or /*! | */
-                beforeText: /^\s*\/\*(\*|\!)(?!\/)([^\*]|\*(?!\/))*$/,
-                afterText: /^\s*\*\/$/,
-                action: { indentAction: vscode.IndentAction.IndentOutdent, appendText: " * " },
-            },
-            {
-                // Begins a multi-line comment (standard or parent doc)
-                // e.g. /** ...| or /*! ...|
-                beforeText: /^\s*\/\*(\*|\!)(?!\/)([^\*]|\*(?!\/))*$/,
-                action: { indentAction, appendText: " * " },
-            },
-            {
-                // Continues a multi-line comment
-                // e.g.  * ...|
-                beforeText: /^(\ \ )*\ \*(\ ([^\*]|\*(?!\/))*)?$/,
-                action: { indentAction, appendText: "* " },
-            },
-            {
-                // Dedents after closing a multi-line comment
-                // e.g.  */|
-                beforeText: /^(\ \ )*\ \*\/\s*$/,
-                action: { indentAction, removeText: 1 },
-            },
-        ],
-    });
+async function activateServer(ctx: Ctx): Promise<RustAnalyzerExtensionApi> {
+    if (ctx.workspace.kind === "Workspace Folder") {
+        ctx.pushExtCleanup(activateTaskProvider(ctx.config));
+    }
+
+    vscode.workspace.onDidChangeWorkspaceFolders(
+        async (_) => ctx.onWorkspaceFolderChanges(),
+        null,
+        ctx.subscriptions
+    );
+    vscode.workspace.onDidChangeConfiguration(
+        async (_) => {
+            await ctx.client?.sendNotification("workspace/didChangeConfiguration", {
+                settings: "",
+            });
+        },
+        null,
+        ctx.subscriptions
+    );
+
+    await ctx.start();
+    return ctx;
+}
+
+function createCommands(): Record<string, CommandFactory> {
+    return {
+        onEnter: {
+            enabled: commands.onEnter,
+            disabled: (_) => () => vscode.commands.executeCommand("default:type", { text: "\n" }),
+        },
+        reload: {
+            enabled: (ctx) => async () => {
+                void vscode.window.showInformationMessage("Reloading rust-analyzer...");
+                await ctx.restart();
+            },
+            disabled: (ctx) => async () => {
+                void vscode.window.showInformationMessage("Reloading rust-analyzer...");
+                await ctx.start();
+            },
+        },
+        startServer: {
+            enabled: (ctx) => async () => {
+                await ctx.start();
+            },
+            disabled: (ctx) => async () => {
+                await ctx.start();
+            },
+        },
+        stopServer: {
+            enabled: (ctx) => async () => {
+                // FIXME: We should re-use the client, that is ctx.deactivate() if none of the configs have changed
+                await ctx.stopAndDispose();
+                ctx.setServerStatus({
+                    health: "stopped",
+                });
+            },
+            disabled: (_) => async () => {},
+        },
+
+        analyzerStatus: { enabled: commands.analyzerStatus },
+        memoryUsage: { enabled: commands.memoryUsage },
+        shuffleCrateGraph: { enabled: commands.shuffleCrateGraph },
+        reloadWorkspace: { enabled: commands.reloadWorkspace },
+        matchingBrace: { enabled: commands.matchingBrace },
+        joinLines: { enabled: commands.joinLines },
+        parentModule: { enabled: commands.parentModule },
+        syntaxTree: { enabled: commands.syntaxTree },
+        viewHir: { enabled: commands.viewHir },
+        viewFileText: { enabled: commands.viewFileText },
+        viewItemTree: { enabled: commands.viewItemTree },
+        viewCrateGraph: { enabled: commands.viewCrateGraph },
+        viewFullCrateGraph: { enabled: commands.viewFullCrateGraph },
+        expandMacro: { enabled: commands.expandMacro },
+        run: { enabled: commands.run },
+        copyRunCommandLine: { enabled: commands.copyRunCommandLine },
+        debug: { enabled: commands.debug },
+        newDebugConfig: { enabled: commands.newDebugConfig },
+        openDocs: { enabled: commands.openDocs },
+        openCargoToml: { enabled: commands.openCargoToml },
+        peekTests: { enabled: commands.peekTests },
+        moveItemUp: { enabled: commands.moveItemUp },
+        moveItemDown: { enabled: commands.moveItemDown },
+        cancelFlycheck: { enabled: commands.cancelFlycheck },
+        ssr: { enabled: commands.ssr },
+        serverVersion: { enabled: commands.serverVersion },
+        // Internal commands which are invoked by the server.
+        applyActionGroup: { enabled: commands.applyActionGroup },
+        applySnippetWorkspaceEdit: { enabled: commands.applySnippetWorkspaceEditCommand },
+        debugSingle: { enabled: commands.debugSingle },
+        gotoLocation: { enabled: commands.gotoLocation },
+        linkToCommand: { enabled: commands.linkToCommand },
+        resolveCodeAction: { enabled: commands.resolveCodeAction },
+        runSingle: { enabled: commands.runSingle },
+        showReferences: { enabled: commands.showReferences },
+    };
 }
diff --git a/src/tools/rust-analyzer/editors/code/src/run.ts b/src/tools/rust-analyzer/editors/code/src/run.ts
index 22e5eda6827d..35627e2fc6be 100644
--- a/src/tools/rust-analyzer/editors/code/src/run.ts
+++ b/src/tools/rust-analyzer/editors/code/src/run.ts
@@ -3,7 +3,7 @@ import * as lc from "vscode-languageclient";
 import * as ra from "./lsp_ext";
 import * as tasks from "./tasks";
 
-import { Ctx } from "./ctx";
+import { CtxInit } from "./ctx";
 import { makeDebugConfig } from "./debug";
 import { Config, RunnableEnvCfg } from "./config";
 
@@ -12,15 +12,15 @@ const quickPickButtons = [
 ];
 
 export async function selectRunnable(
-    ctx: Ctx,
+    ctx: CtxInit,
     prevRunnable?: RunnableQuickPick,
     debuggeeOnly = false,
     showButtons: boolean = true
 ): Promise<RunnableQuickPick | undefined> {
     const editor = ctx.activeRustEditor;
-    const client = ctx.client;
-    if (!editor || !client) return;
+    if (!editor) return;
 
+    const client = ctx.client;
     const textDocument: lc.TextDocumentIdentifier = {
         uri: editor.document.uri.toString(),
     };
diff --git a/src/tools/rust-analyzer/lib/lsp-server/Cargo.toml b/src/tools/rust-analyzer/lib/lsp-server/Cargo.toml
index 5922bbfdb483..9bba9e87ecb5 100644
--- a/src/tools/rust-analyzer/lib/lsp-server/Cargo.toml
+++ b/src/tools/rust-analyzer/lib/lsp-server/Cargo.toml
@@ -13,4 +13,4 @@ serde = { version = "1.0.144", features = ["derive"] }
 crossbeam-channel = "0.5.6"
 
 [dev-dependencies]
-lsp-types = "0.93.1"
+lsp-types = "=0.93.2"
diff --git a/src/tools/rust-analyzer/triagebot.toml b/src/tools/rust-analyzer/triagebot.toml
index fa0824ac53c0..a910e012b734 100644
--- a/src/tools/rust-analyzer/triagebot.toml
+++ b/src/tools/rust-analyzer/triagebot.toml
@@ -1 +1,11 @@
 [assign]
+
+[shortcut]
+
+[relabel]
+allow-unauthenticated = [
+    "S-*",
+]
+
+[autolabel."S-waiting-on-review"]
+new_pr = true
diff --git a/src/tools/rustdoc-gui/tester.js b/src/tools/rustdoc-gui/tester.js
index 70d5f94472f6..d40d9a3cb542 100644
--- a/src/tools/rustdoc-gui/tester.js
+++ b/src/tools/rustdoc-gui/tester.js
@@ -149,6 +149,7 @@ async function main(argv) {
         // This is more convenient that setting fields one by one.
         let args = [
             "--variable", "DOC_PATH", opts["doc_folder"], "--enable-fail-on-js-error",
+            "--allow-file-access-from-files",
         ];
         if (opts["debug"]) {
             debug = true;
diff --git a/src/tools/rustdoc-js/tester.js b/src/tools/rustdoc-js/tester.js
index df3185758bfc..3da4fed33e11 100644
--- a/src/tools/rustdoc-js/tester.js
+++ b/src/tools/rustdoc-js/tester.js
@@ -307,10 +307,13 @@ function runChecks(testFile, doSearch, parseQuery) {
  *   `parseQuery` function exported from the search module.
  */
 function loadSearchJS(doc_folder, resource_suffix) {
-    const searchJs = path.join(doc_folder, "search" + resource_suffix + ".js");
     const searchIndexJs = path.join(doc_folder, "search-index" + resource_suffix + ".js");
     const searchIndex = require(searchIndexJs);
-    const searchModule = require(searchJs);
+
+    const staticFiles = path.join(doc_folder, "static.files");
+    const searchJs = fs.readdirSync(staticFiles).find(
+        f => f.match(/search.*\.js$/));
+    const searchModule = require(path.join(staticFiles, searchJs));
     const searchWords = searchModule.initSearch(searchIndex.searchIndex);
 
     return {
diff --git a/src/tools/rustdoc/main.rs b/src/tools/rustdoc/main.rs
index 5b499a1fa1fa..b81f46d1211c 100644
--- a/src/tools/rustdoc/main.rs
+++ b/src/tools/rustdoc/main.rs
@@ -1,3 +1,6 @@
+#![feature(unix_sigpipe)]
+
+#[unix_sigpipe = "sig_dfl"]
 fn main() {
     rustdoc::main()
 }
diff --git a/src/tools/rustfmt/src/expr.rs b/src/tools/rustfmt/src/expr.rs
index 3105882e2d30..7750df0fff3a 100644
--- a/src/tools/rustfmt/src/expr.rs
+++ b/src/tools/rustfmt/src/expr.rs
@@ -399,6 +399,7 @@ pub(crate) fn format_expr(
             }
         }
         ast::ExprKind::Underscore => Some("_".to_owned()),
+        ast::ExprKind::IncludedBytes(..) => unreachable!(),
         ast::ExprKind::Err => None,
     };
 
diff --git a/src/tools/rustfmt/src/parse/session.rs b/src/tools/rustfmt/src/parse/session.rs
index 6efeee98fea6..6bfec79cd703 100644
--- a/src/tools/rustfmt/src/parse/session.rs
+++ b/src/tools/rustfmt/src/parse/session.rs
@@ -134,6 +134,7 @@ fn default_handler(
             false,
             None,
             false,
+            false,
         ))
     };
     Handler::with_emitter(
diff --git a/src/tools/rustfmt/src/utils.rs b/src/tools/rustfmt/src/utils.rs
index cd852855602e..c47b3b314dd4 100644
--- a/src/tools/rustfmt/src/utils.rs
+++ b/src/tools/rustfmt/src/utils.rs
@@ -496,6 +496,7 @@ pub(crate) fn is_block_expr(context: &RewriteContext<'_>, expr: &ast::Expr, repr
         | ast::ExprKind::Continue(..)
         | ast::ExprKind::Err
         | ast::ExprKind::Field(..)
+        | ast::ExprKind::IncludedBytes(..)
         | ast::ExprKind::InlineAsm(..)
         | ast::ExprKind::Let(..)
         | ast::ExprKind::Path(..)
diff --git a/src/tools/tidy/Cargo.toml b/src/tools/tidy/Cargo.toml
index 471d78a2922a..97d038da702d 100644
--- a/src/tools/tidy/Cargo.toml
+++ b/src/tools/tidy/Cargo.toml
@@ -7,8 +7,10 @@ autobins = false
 [dependencies]
 cargo_metadata = "0.14"
 regex = "1"
+miropt-test-tools = { path = "../miropt-test-tools" }
 lazy_static = "1"
 walkdir = "2"
+ignore = "0.4.18"
 
 [[bin]]
 name = "rust-tidy"
diff --git a/src/tools/tidy/src/deps.rs b/src/tools/tidy/src/deps.rs
index 8a0239eceff1..35fa968f977a 100644
--- a/src/tools/tidy/src/deps.rs
+++ b/src/tools/tidy/src/deps.rs
@@ -23,6 +23,7 @@ const LICENSES: &[&str] = &[
     "MIT OR Apache-2.0 OR Zlib",                // tinyvec_macros
     "MIT OR Zlib OR Apache-2.0",                // miniz_oxide
     "(MIT OR Apache-2.0) AND Unicode-DFS-2016", // unicode_ident
+    "Unicode-DFS-2016",                         // tinystr and icu4x
 ];
 
 /// These are exceptions to Rust's permissive licensing policy, and
@@ -109,6 +110,7 @@ const PERMITTED_RUSTC_DEPENDENCIES: &[&str] = &[
     "datafrog",
     "difference",
     "digest",
+    "displaydoc",
     "dlmalloc",
     "either",
     "ena",
diff --git a/src/tools/tidy/src/lib.rs b/src/tools/tidy/src/lib.rs
index fc0bce585723..698e4850bea9 100644
--- a/src/tools/tidy/src/lib.rs
+++ b/src/tools/tidy/src/lib.rs
@@ -47,6 +47,7 @@ pub mod error_codes_check;
 pub mod errors;
 pub mod extdeps;
 pub mod features;
+pub mod mir_opt_tests;
 pub mod pal;
 pub mod primitive_docs;
 pub mod style;
diff --git a/src/tools/tidy/src/main.rs b/src/tools/tidy/src/main.rs
index ca785042aaa6..b0b11cafca5a 100644
--- a/src/tools/tidy/src/main.rs
+++ b/src/tools/tidy/src/main.rs
@@ -31,6 +31,7 @@ fn main() {
     let args: Vec<String> = env::args().skip(1).collect();
 
     let verbose = args.iter().any(|s| *s == "--verbose");
+    let bless = args.iter().any(|s| *s == "--bless");
 
     let bad = std::sync::Arc::new(AtomicBool::new(false));
 
@@ -64,6 +65,7 @@ fn main() {
         // Checks over tests.
         check!(debug_artifacts, &src_path);
         check!(ui_tests, &src_path);
+        check!(mir_opt_tests, &src_path, bless);
 
         // Checks that only make sense for the compiler.
         check!(errors, &compiler_path);
diff --git a/src/tools/tidy/src/mir_opt_tests.rs b/src/tools/tidy/src/mir_opt_tests.rs
new file mode 100644
index 000000000000..018573284ea7
--- /dev/null
+++ b/src/tools/tidy/src/mir_opt_tests.rs
@@ -0,0 +1,74 @@
+//! Tidy check to ensure that mir opt directories do not have stale files or dashes in file names
+
+use std::collections::HashSet;
+use std::path::{Path, PathBuf};
+
+fn check_unused_files(path: &Path, bless: bool, bad: &mut bool) {
+    let mut rs_files = Vec::<PathBuf>::new();
+    let mut output_files = HashSet::<PathBuf>::new();
+    let files = walkdir::WalkDir::new(&path.join("test/mir-opt")).into_iter();
+
+    for file in files.filter_map(Result::ok).filter(|e| e.file_type().is_file()) {
+        let filepath = file.path();
+        if filepath.extension() == Some("rs".as_ref()) {
+            rs_files.push(filepath.to_owned());
+        } else {
+            output_files.insert(filepath.to_owned());
+        }
+    }
+
+    for file in rs_files {
+        for bw in [32, 64] {
+            for output_file in miropt_test_tools::files_for_miropt_test(&file, bw) {
+                output_files.remove(&output_file.expected_file);
+            }
+        }
+    }
+
+    for extra in output_files {
+        if extra.file_name() != Some("README.md".as_ref()) {
+            if !bless {
+                tidy_error!(
+                    bad,
+                    "the following output file is not associated with any mir-opt test, you can remove it: {}",
+                    extra.display()
+                );
+            } else {
+                let _ = std::fs::remove_file(extra);
+            }
+        }
+    }
+}
+
+fn check_dash_files(path: &Path, bless: bool, bad: &mut bool) {
+    for file in walkdir::WalkDir::new(&path.join("test/mir-opt"))
+        .into_iter()
+        .filter_map(Result::ok)
+        .filter(|e| e.file_type().is_file())
+    {
+        let path = file.path();
+        if path.extension() == Some("rs".as_ref()) {
+            if let Some(name) = path.file_name().and_then(|s| s.to_str()) {
+                if name.contains('-') {
+                    if !bless {
+                        tidy_error!(
+                            bad,
+                            "mir-opt test files should not have dashes in them: {}",
+                            path.display()
+                        );
+                    } else {
+                        let new_name = name.replace('-', "_");
+                        let mut new_path = path.to_owned();
+                        new_path.set_file_name(new_name);
+                        let _ = std::fs::rename(path, new_path);
+                    }
+                }
+            }
+        }
+    }
+}
+
+pub fn check(path: &Path, bless: bool, bad: &mut bool) {
+    check_unused_files(path, bless, bad);
+    check_dash_files(path, bless, bad);
+}
diff --git a/src/tools/tidy/src/ui_tests.rs b/src/tools/tidy/src/ui_tests.rs
index c600f99c2c4b..21c6a96747ee 100644
--- a/src/tools/tidy/src/ui_tests.rs
+++ b/src/tools/tidy/src/ui_tests.rs
@@ -2,43 +2,50 @@
 //! - the number of entries in each directory must be less than `ENTRY_LIMIT`
 //! - there are no stray `.stderr` files
 
+use ignore::Walk;
+use ignore::WalkBuilder;
 use std::fs;
 use std::path::Path;
 
 const ENTRY_LIMIT: usize = 1000;
 // FIXME: The following limits should be reduced eventually.
-const ROOT_ENTRY_LIMIT: usize = 948;
-const ISSUES_ENTRY_LIMIT: usize = 2117;
+const ROOT_ENTRY_LIMIT: usize = 939;
+const ISSUES_ENTRY_LIMIT: usize = 2085;
 
 fn check_entries(path: &Path, bad: &mut bool) {
-    let dirs = walkdir::WalkDir::new(&path.join("test/ui"))
-        .into_iter()
-        .filter_entry(|e| e.file_type().is_dir());
-    for dir in dirs {
-        if let Ok(dir) = dir {
-            let dir_path = dir.path();
+    for dir in Walk::new(&path.join("test/ui")) {
+        if let Ok(entry) = dir {
+            if entry.file_type().map(|ft| ft.is_dir()).unwrap_or(false) {
+                let dir_path = entry.path();
+                // Use special values for these dirs.
+                let is_root = path.join("test/ui") == dir_path;
+                let is_issues_dir = path.join("test/ui/issues") == dir_path;
+                let limit = if is_root {
+                    ROOT_ENTRY_LIMIT
+                } else if is_issues_dir {
+                    ISSUES_ENTRY_LIMIT
+                } else {
+                    ENTRY_LIMIT
+                };
 
-            // Use special values for these dirs.
-            let is_root = path.join("test/ui") == dir_path;
-            let is_issues_dir = path.join("test/ui/issues") == dir_path;
-            let limit = if is_root {
-                ROOT_ENTRY_LIMIT
-            } else if is_issues_dir {
-                ISSUES_ENTRY_LIMIT
-            } else {
-                ENTRY_LIMIT
-            };
+                let count = WalkBuilder::new(&dir_path)
+                    .max_depth(Some(1))
+                    .build()
+                    .into_iter()
+                    .collect::<Vec<_>>()
+                    .len()
+                    - 1; // remove the dir itself
 
-            let count = std::fs::read_dir(dir_path).unwrap().count();
-            if count > limit {
-                tidy_error!(
-                    bad,
-                    "following path contains more than {} entries, \
-                    you should move the test to some relevant subdirectory (current: {}): {}",
-                    limit,
-                    count,
-                    dir_path.display()
-                );
+                if count > limit {
+                    tidy_error!(
+                        bad,
+                        "following path contains more than {} entries, \
+                            you should move the test to some relevant subdirectory (current: {}): {}",
+                        limit,
+                        count,
+                        dir_path.display()
+                    );
+                }
             }
         }
     }
diff --git a/src/tools/x/src/main.rs b/src/tools/x/src/main.rs
index 9187c3551d7d..02c364dabf96 100644
--- a/src/tools/x/src/main.rs
+++ b/src/tools/x/src/main.rs
@@ -8,7 +8,8 @@
 //! `x.py`, in that order of preference.
 
 use std::{
-    env, io,
+    env::{self, consts::EXE_EXTENSION},
+    io,
     process::{self, Command, ExitStatus},
 };
 
@@ -27,12 +28,12 @@ fn python() -> &'static str {
 
     for dir in env::split_paths(&val) {
         // `python` should always take precedence over python2 / python3 if it exists
-        if dir.join(PYTHON).exists() {
+        if dir.join(PYTHON).with_extension(EXE_EXTENSION).exists() {
             return PYTHON;
         }
 
-        python2 |= dir.join(PYTHON2).exists();
-        python3 |= dir.join(PYTHON3).exists();
+        python2 |= dir.join(PYTHON2).with_extension(EXE_EXTENSION).exists();
+        python3 |= dir.join(PYTHON3).with_extension(EXE_EXTENSION).exists();
     }
 
     // try 3 before 2
diff --git a/src/version b/src/version
index b6148bc0a759..65ee0959841f 100644
--- a/src/version
+++ b/src/version
@@ -1 +1 @@
-1.66.0
+1.67.0
diff --git a/triagebot.toml b/triagebot.toml
index 04c2a0507acc..985e065652d6 100644
--- a/triagebot.toml
+++ b/triagebot.toml
@@ -12,6 +12,7 @@ allow-unauthenticated = [
     "T-*",
     "WG-*",
     "const-hack",
+    "llvm-main",
     "needs-fcp",
     "relnotes",
     "requires-nightly",
@@ -20,8 +21,6 @@ allow-unauthenticated = [
     "AsyncAwait-OnDeck",
 ]
 
-[assign]
-
 [glacier]
 
 [ping.icebreakers-llvm]
@@ -183,6 +182,7 @@ trigger_files = [
     "x.ps1",
     "src/bootstrap",
     "src/tools/rust-installer",
+    "src/tools/x",
     "configure",
     "Cargo.toml",
     "Cargo.lock",
@@ -246,6 +246,9 @@ trigger_files = [
     "src/version"
 ]
 
+[autolabel."S-waiting-on-review"]
+new_pr = true
+
 [notify-zulip."I-prioritize"]
 zulip_stream = 245100 # #t-compiler/wg-prioritization/alerts
 topic = "#{number} {title}"
@@ -420,3 +423,165 @@ cc = ["@davidtwco", "@compiler-errors", "@JohnTitor", "@estebank", "@TaKO8Ki"]
 [mentions."compiler/rustc_macros/src/diagnostics"]
 message = "`rustc_macros::diagnostics` was changed"
 cc = ["@davidtwco", "@compiler-errors", "@JohnTitor", "@estebank", "@TaKO8Ki"]
+
+[mentions."compiler/rustc_target/src/spec"]
+message = """
+These commits modify **compiler targets**.
+(See the [Target Tier Policy](https://doc.rust-lang.org/nightly/rustc/target-tier-policy.html).)
+"""
+
+[assign]
+warn_non_default_branch = true
+contributing_url = "https://rustc-dev-guide.rust-lang.org/contributing.html"
+
+[assign.adhoc_groups]
+compiler-team = [
+    "@cjgillot",
+    "@estebank",
+    "@petrochenkov",
+    "@davidtwco",
+    "@oli-obk",
+    "@lcnr",
+    "@nagisa",
+    "@wesleywiser",
+]
+compiler-team-contributors = [
+    "@compiler-errors",
+    "@eholk",
+    "@jackh726",
+    "@fee1-dead",
+    "@TaKO8Ki",
+]
+compiler = [
+    "compiler-team",
+    "compiler-team-contributors",
+]
+libs = [
+    "@joshtriplett",
+    "@Mark-Simulacrum",
+    "@m-ou-se",
+    "@thomcc",
+]
+bootstrap = [
+    "@Mark-Simulacrum",
+    "@jyn514",
+]
+infra-ci = [
+    "@Mark-Simulacrum",
+    "@pietroalbini",
+    "@jyn514",
+]
+rustdoc = [
+    "@jsha",
+    "@GuillaumeGomez",
+    "@CraftSpider",
+    "@notriddle",
+]
+docs = [
+    "@ehuss",
+    "@GuillaumeGomez",
+    "@JohnTitor",
+]
+query-system = [
+    "@cjgillot",
+]
+incremental = [
+    "@michaelwoerister",
+    "@wesleywiser",
+]
+diagnostics = [
+    "@compiler-errors",
+    "@davidtwco",
+    "@estebank",
+    "@oli-obk",
+    "@TaKO8Ki",
+]
+parser = [
+    "@davidtwco",
+    "@estebank",
+    "@nnethercote",
+    "@petrochenkov",
+]
+lexer = [
+    "@nnethercote",
+    "@petrochenkov",
+]
+mir = [
+    "@davidtwco",
+    "@oli-obk",
+]
+mir-opt = [
+    "@nagisa",
+    "@oli-obk",
+    "@wesleywiser",
+]
+types = [
+    "@compiler-errors",
+    "@jackh726",
+    "@lcnr",
+    "@oli-obk",
+    "@spastorino",
+]
+borrowck = [
+    "@davidtwco",
+    "@pnkfelix",
+]
+ast_lowering = [
+    "@spastorino",
+]
+fallback = [
+    "@Mark-Simulacrum"
+]
+
+[assign.owners]
+"/.github/workflows" =                       ["infra-ci"]
+"/Cargo.lock" =                              ["@Mark-Simulacrum"]
+"/Cargo.toml" =                              ["@Mark-Simulacrum"]
+"/compiler" =                                ["compiler"]
+"/compiler/rustc_apfloat" =                  ["@eddyb"]
+"/compiler/rustc_ast" =                      ["compiler", "parser"]
+"/compiler/rustc_ast_lowering" =             ["compiler", "ast_lowering"]
+"/compiler/rustc_hir_analysis" =             ["compiler", "types"]
+"/compiler/rustc_lexer" =                    ["compiler", "lexer"]
+"/compiler/rustc_llvm" =                     ["@cuviper"]
+"/compiler/rustc_middle/src/mir" =           ["compiler", "mir"]
+"/compiler/rustc_middle/src/traits" =        ["compiler", "types"]
+"/compiler/rustc_const_eval/src/interpret" = ["compiler", "mir"]
+"/compiler/rustc_const_eval/src/transform" = ["compiler", "mir-opt"]
+"/compiler/rustc_mir_build/src/build" =      ["compiler", "mir"]
+"/compiler/rustc_parse" =                    ["compiler", "parser"]
+"/compiler/rustc_parse/src/lexer" =          ["compiler", "lexer"]
+"/compiler/rustc_query_impl" =               ["compiler", "query-system"]
+"/compiler/rustc_query_system" =             ["compiler", "query-system"]
+"/compiler/rustc_trait_selection" =          ["compiler", "types"]
+"/compiler/rustc_traits" =                   ["compiler", "types"]
+"/compiler/rustc_type_ir" =                  ["compiler", "types"]
+"/library/alloc" =                           ["libs"]
+"/library/core" =                            ["libs", "@scottmcm"]
+"/library/panic_abort" =                     ["libs"]
+"/library/panic_unwind" =                    ["libs"]
+"/library/proc_macro" =                      ["@petrochenkov"]
+"/library/std" =                             ["libs"]
+"/library/std/src/sys/windows" =             ["@ChrisDenton", "@thomcc"]
+"/library/stdarch" =                         ["libs"]
+"/library/test" =                            ["libs"]
+"/src/bootstrap" =                           ["bootstrap"]
+"/src/ci" =                                  ["infra-ci"]
+"/src/doc" =                                 ["docs"]
+"/src/doc/rustdoc" =                         ["rustdoc"]
+"/src/etc" =                                 ["@Mark-Simulacrum"]
+"/src/librustdoc" =                          ["rustdoc"]
+"/src/llvm-project" =                        ["@cuviper"]
+"/src/rustdoc-json-types" =                  ["rustdoc"]
+"/src/stage0.json" =                         ["bootstrap"]
+"/src/test/ui" =                             ["compiler"]
+"/src/tools/cargo" =                         ["@ehuss", "@joshtriplett"]
+"/src/tools/compiletest" =                   ["bootstrap"]
+"/src/tools/linkchecker" =                   ["@ehuss"]
+"/src/tools/rust-installer" =                ["bootstrap"]
+"/src/tools/rustbook" =                      ["@ehuss"]
+"/src/tools/rustdoc" =                       ["rustdoc"]
+"/src/tools/rustdoc-js" =                    ["rustdoc"]
+"/src/tools/rustdoc-themes" =                ["rustdoc"]
+"/src/tools/tidy" =                          ["bootstrap"]
+"/src/tools/x" =                             ["bootstrap"]
diff --git a/x b/x
index 704d0f791f33..4309b82627c9 100755
--- a/x
+++ b/x
@@ -29,5 +29,11 @@ for SEARCH_PYTHON in py python3 python python2; do
         exec "$python" $extra_arg "$xpy" "$@"
     fi
 done
+
+python=$(bash -c "compgen -c python" | grep '^python[2-3]\.[0-9]\+$' | head -n1)
+if ! [ "$python" = "" ]; then
+    exec "$python" "$xpy" "$@"
+fi
+
 echo "$0: error: did not find python installed" >&2
 exit 1
diff --git a/x.ps1 b/x.ps1
index 86cea606591b..81b98919f436 100755
--- a/x.ps1
+++ b/x.ps1
@@ -10,11 +10,15 @@ foreach ($arg in $args) {
     $xpy_args += """$arg"""
 }
 
+function Get-Application($app) {
+    return Get-Command $app -ErrorAction SilentlyContinue -CommandType Application
+}
+
 foreach ($python in "py", "python3", "python", "python2") {
     # NOTE: this only tests that the command exists in PATH, not that it's actually
     # executable. The latter is not possible in a portable way, see
     # https://github.com/PowerShell/PowerShell/issues/12625.
-    if (Get-Command $python -ErrorAction SilentlyContinue) {
+    if (Get-Application $python) {
         if ($python -eq "py") {
             # Use python3, not python2
             $xpy_args = @("-3") + $xpy_args
@@ -24,5 +28,12 @@ foreach ($python in "py", "python3", "python", "python2") {
     }
 }
 
+$found = (Get-Application "python*" | Where-Object {$_.name -match '^python[2-3]\.[0-9]+(\.exe)?$'})
+if (($null -ne $found) -and ($found.Length -ge 1)) {
+    $python = $found[0]
+    $process = Start-Process -NoNewWindow -Wait -PassThru $python $xpy_args
+    Exit $process.ExitCode
+}
+
 Write-Error "${PSCommandPath}: error: did not find python installed"
 Exit 1