From 348bfe3e355a4479287d3940ca6b87f9be967040 Mon Sep 17 00:00:00 2001
From: Josh Stone <jistone@redhat.com>
Date: Tue, 13 Jan 2026 10:54:33 -0800
Subject: [PATCH] compiler: upgrade to hashbrown 0.16.1

See also #135634, #149159, and rust-lang/hashbrown#662.

This includes an in-tree upgrade of `indexmap` as well, which uses the
new `HashTable` buckets API internally, hopefully impacting performance
for the better!
---
 Cargo.lock                                 | 19 +++++++++++--------
 compiler/rustc_data_structures/Cargo.toml  |  4 ++--
 compiler/rustc_mir_transform/Cargo.toml    |  2 +-
 compiler/rustc_query_system/Cargo.toml     |  2 +-
 src/bootstrap/src/utils/proc_macro_deps.rs |  1 +
 5 files changed, 16 insertions(+), 12 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index bf28939ac87b..45d01c486faf 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1670,9 +1670,12 @@ dependencies = [
 
 [[package]]
 name = "hashbrown"
-version = "0.16.0"
+version = "0.16.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5419bdc4f6a9207fbeba6d11b604d481addf78ecd10c11ad51e76c2f6482748d"
+checksum = "841d1cc9bed7f9236f321df977030373f4a4163ae1a7dbfe1a51a2c1a51d9100"
+dependencies = [
+ "foldhash 0.2.0",
+]
 
 [[package]]
 name = "heck"
@@ -1950,12 +1953,12 @@ checksum = "964de6e86d545b246d84badc0fef527924ace5134f30641c203ef52ba83f58d5"
 
 [[package]]
 name = "indexmap"
-version = "2.12.0"
+version = "2.12.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6717a8d2a5a929a1a2eb43a12812498ed141a0bcfb7e8f7844fbdbe4303bba9f"
+checksum = "0ad4bb2b565bca0645f4d68c5c9af97fba094e9791da685bf83cb5f3ce74acf2"
 dependencies = [
  "equivalent",
- "hashbrown 0.16.0",
+ "hashbrown 0.16.1",
  "serde",
  "serde_core",
 ]
@@ -3730,7 +3733,7 @@ dependencies = [
  "either",
  "elsa",
  "ena",
- "hashbrown 0.15.5",
+ "hashbrown 0.16.1",
  "indexmap",
  "jobserver",
  "libc",
@@ -4346,7 +4349,7 @@ name = "rustc_mir_transform"
 version = "0.0.0"
 dependencies = [
  "either",
- "hashbrown 0.15.5",
+ "hashbrown 0.16.1",
  "itertools",
  "rustc_abi",
  "rustc_arena",
@@ -4557,7 +4560,7 @@ dependencies = [
 name = "rustc_query_system"
 version = "0.0.0"
 dependencies = [
- "hashbrown 0.15.5",
+ "hashbrown 0.16.1",
  "parking_lot",
  "rustc_abi",
  "rustc_ast",
diff --git a/compiler/rustc_data_structures/Cargo.toml b/compiler/rustc_data_structures/Cargo.toml
index c8296e05f6bd..f358ffffb47d 100644
--- a/compiler/rustc_data_structures/Cargo.toml
+++ b/compiler/rustc_data_structures/Cargo.toml
@@ -10,7 +10,7 @@ bitflags = "2.4.1"
 either = "1.0"
 elsa = "1.11.0"
 ena = "0.14.3"
-indexmap = "2.4.0"
+indexmap = "2.12.1"
 jobserver_crate = { version = "0.1.28", package = "jobserver" }
 measureme = "12.0.1"
 parking_lot = "0.12"
@@ -31,7 +31,7 @@ tracing = "0.1"
 # tidy-alphabetical-end
 
 [dependencies.hashbrown]
-version = "0.15.2"
+version = "0.16.1"
 default-features = false
 features = ["nightly"] # for may_dangle
 
diff --git a/compiler/rustc_mir_transform/Cargo.toml b/compiler/rustc_mir_transform/Cargo.toml
index 6df7a869ca28..22de197d374a 100644
--- a/compiler/rustc_mir_transform/Cargo.toml
+++ b/compiler/rustc_mir_transform/Cargo.toml
@@ -6,7 +6,7 @@ edition = "2024"
 [dependencies]
 # tidy-alphabetical-start
 either = "1"
-hashbrown = "0.15"
+hashbrown = { version = "0.16.1", default-features = false }
 itertools = "0.12"
 rustc_abi = { path = "../rustc_abi" }
 rustc_arena = { path = "../rustc_arena" }
diff --git a/compiler/rustc_query_system/Cargo.toml b/compiler/rustc_query_system/Cargo.toml
index 7480ba03474f..73ab03576dec 100644
--- a/compiler/rustc_query_system/Cargo.toml
+++ b/compiler/rustc_query_system/Cargo.toml
@@ -25,6 +25,6 @@ tracing = "0.1"
 # tidy-alphabetical-end
 
 [dependencies.hashbrown]
-version = "0.15.2"
+version = "0.16.1"
 default-features = false
 features = ["nightly"] # for may_dangle
diff --git a/src/bootstrap/src/utils/proc_macro_deps.rs b/src/bootstrap/src/utils/proc_macro_deps.rs
index 71b6aacdebed..f1bf6e399fb1 100644
--- a/src/bootstrap/src/utils/proc_macro_deps.rs
+++ b/src/bootstrap/src/utils/proc_macro_deps.rs
@@ -22,6 +22,7 @@ pub static CRATES: &[&str] = &[
     "fluent-langneg",
     "fluent-syntax",
     "fnv",
+    "foldhash",
     "generic-array",
     "hashbrown",
     "heck",